trichostatin-a and Lung-Neoplasms

Both tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and histone deacetylase inhibitors (HDIs) show promise for the treatment of cancer. However, in a number of reports they have been proven ineffective to induce cell death when applied as single agents. In this study, we show that A549 lung carcinoma cells and PC-3 prostate carcinoma cells underwent substantial apoptosis when coexposed to TRAIL and either suberoylanilide hydroxamic acid, sodium butyrate or trichostatin A. HDIs and TRAIL synergized in activation of capase-3, induction of internucleosomal DNA fragmentation and promoting mitochondrial damage. Significantly, cotreatment with minimally toxic doses of HDIs and TRAIL resulted in a marked apoptotic response in both cell lines. These data provide a rationale for a more in-depth exploration into the potential of combining TRAIL and HDIs as a valuable anticancer strategy.

Topics: Antineoplastic Agents; Apoptosis; Apoptosis Regulatory Proteins; Butyric Acid; Caspase 3; Caspases; Cell Line, Tumor; Drug Synergism; Enzyme Inhibitors; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung Neoplasms; Male; Membrane Glycoproteins; Prostatic Neoplasms; TNF-Related Apoptosis-Inducing Ligand; Tumor Necrosis Factor-alpha; Vorinostat

A fragment recruitment process was conducted to pinpoint a suitable fragment for installation in the HDAC inhibitory template to furnish agents endowed with the potential to treat lung cancer. Resultantly, Ring C expanded deoxyvasicinone was selected as an appropriate surface recognition part that was accommodated in the HDAC three-component model. Delightfully, fused quinazolinone 6 demonstrating a magnificent anticancer profile against KRAS and EGFR mutant lung cancer cell lines (IC

Topics: Animals; Antineoplastic Agents; Cell Line, Tumor; Cell Proliferation; Histone Deacetylase Inhibitors; Hydrogen-Ion Concentration; Lung Neoplasms; Mice; Nanoparticle Drug Delivery System; Quinazolines; Quinazolinones

Drug-resistant capacity in a small population of tumor-initiating cancer stem cells (tiCSCs) can be due to aberrant epigenetic changes. However, currently available conventional detection methods are inappropriate and cannot be applied to investigate the scarce population (tiCSCs). In addition, selective inhibitor drugs are shown to reverse epigenetic changes; however, each cancer type is discrete. Hence, it is essential to probe the resultant changes in tiCSCs even after therapy. Therefore, we have developed a multimode nanoplatform to investigate tiCSCs, detect epigenetic changes, and subsequently explore their transformation signals following drug therapy. We performed this by developing a surface-enhanced Raman scattering (SERS)-active nanoplatform integrated with n-dopant using an ultrafast laser ionization technique. The dopant functionalization enhances Raman scattering ability and permits label-free analysis of biomarkers in tiCSCs with the resolution down to the cellular level. Here, we investigated epigenetic biomarkers of tiCSCs in pancreatic and lung cancers. An extended study using inhibitor drugs demonstrates an unexpected increase of tiCSCs from lung cancer; this difference can be attributed to transformation changes in lung tiCSC. Thus, our work brings new insight into the differentiation abilities of CSCs upon epigenetic reversal, emphasizing unique perceptions in cancer treatment.

Topics: Biomarkers, Tumor; Cell Cycle Checkpoints; Cell Line, Tumor; Decitabine; Epigenesis, Genetic; Humans; Hydroxamic Acids; Lasers; Lung Neoplasms; Nanostructures; Neoplastic Stem Cells; Pancreatic Neoplasms; Phosphorus; Silicon; Spectrum Analysis, Raman

Histone deacetylase (HDAC) inhibitors have a potential therapeutic role for non-small cell lung cancer (NSCLC). However, more preclinical studies of HDAC inhibitors in NSCLC and normal lung epithelial cells are required to evaluate their antitumor activities and mechanisms. The bicellular tight junction molecule claudin-2 (CLDN-2) is highly expressed in lung adenocarcinoma tissues and increase the proliferation of adenocarcinoma cells. Downregulation of the tricellular tight junction molecule angulin-1/LSR induces malignancy via EGF-dependent CLDN-2 and TGF-β-dependent cellular metabolism in human lung adenocarcinoma cells. In the present study, to investigate the detailed mechanisms of the antitumor activities of HDAC inhibitors in lung adenocarcinoma, human lung adenocarcinoma A549 cells and normal lung epithelial cells were treated with the HDAC inibitors Trichostatin A (TSA) and Quisinostat (JNJ-2648158) with or without TGF-β. Both HDAC inhibitors increased anguin-1/LSR, decrease CLDN-2, promoted G1 arrest and prevented the migration of A549 cells. Furthermore, TSA but not Quisinostat with or without TGF-β induced cellular metabolism indicated as the mitochondrial respiration measured using the oxygen consumption rate. In normal human lung epithelial cells, treatment with TSA and Quisinostat increased expression of LSR and CLDN-2 and decreased that of CLDN-1 with or without TGF-β in 2D culture. Quisinostat but not TSA with TGF-β increased CLDN-7 expression in 2D culture. Both HDAC inhibitors prevented disruption of the epithelial barrier measured as the permeability of FD-4 induced by TGF-β in 2.5D culture. TSA and Quisinostat have potential for use in therapy for lung adenocarcinoma via changes in the expression of angulin-1/LSR and CLDN-2.

Topics: Antineoplastic Agents; Carcinoma, Non-Small-Cell Lung; Cell Movement; Cell Proliferation; Cells, Cultured; Drug Screening Assays, Antitumor; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung Neoplasms; Tight Junction Proteins

Topics: Animals; Antineoplastic Agents; Apoptosis; Carcinoma, Non-Small-Cell Lung; Catalytic Domain; Cell Line, Tumor; Cell Proliferation; Drug Screening Assays, Antitumor; Histone Deacetylase 6; Histone Deacetylase Inhibitors; HSP90 Heat-Shock Proteins; Humans; Hydroxamic Acids; Isoindoles; Lung Neoplasms; Male; Mice, Inbred BALB C; Molecular Docking Simulation; Protein Binding; Xenograft Model Antitumor Assays

In the present study, we investigated the p53-independent mechanism by which quercetin (Q) increased apoptosis in human lung cancer H1299 cells exposed to trichostatin A (TSA), a histone deacetylase inhibitor. We also investigated the role of Q in increasing the acetylation of histones H3 and H4 and the possible mechanism. Q at 5 μM significantly increased apoptosis by 88% in H1299 cells induced by TSA at 72 h. Q also significantly increased TSA-induced death receptor 5 (DR5) mRNA and protein expression as well as caspase-10/3 activities in H1299 cells. Transfection of DR5 siRNA into H1299 cells significantly diminished the enhancing effects of Q on TSA-induced apoptosis. Furthermore, TSA in combination with Q rather than TSA alone significantly increased p300 expression. Transfection of p300 siRNA in H1299 cells significantly diminished the increase of histone H3/H4 acetylation, DR5 protein expression, caspase-10/3 activity and apoptosis induced by Q. In addition, similar effects of Q were observed when Q was combined with vorinostat, another FDA-approved histone deacetylase inhibitor. These data suggest that the up-regulation of p300 expression, which in turn increases histone acetylation and DR5 expression, plays an important role in the enhancing effect of Q on TSA/vorinostat- induced apoptosis in H1299 cells.

Topics: Antineoplastic Agents; E1A-Associated p300 Protein; Humans; Hydroxamic Acids; Lung Neoplasms; Quercetin; Tumor Cells, Cultured; Tumor Suppressor Protein p53; Up-Regulation; Vorinostat

Insulin-like growth factor (IGF) signaling plays an important role in tumorigenesis and metastasis. Here, we analyzed insulin-like growth factor (IGF) binding protein-2 (IGFBP2) expression in 81 lung cancer patients and 36 controls consisting of healthy and benign pulmonary lesion participants for comparison, then validated the IGFBP2 expression in additional 84 lung cancer patients, and evaluated the prognostic and chemoresistant significance of IGFBP2 in two cohorts respectively. Next we detected the reversal effect of trichostatin A (TSA) on chemoresistance in cell lines with high IGFBP2 expression. As a result, the mean expression of IGFBP2 in lung cancer patients was significantly higher than that in controls and increased with lung cancer progressed to advanced stage. In addition, high IGFBP2 expression was independently predictive for chemoresistance; over-expressed IGFBP2 enhances cell activity and TSA can reverse the chemoresistance induced by high IGFBP2 expression through enhancing autophagy. Furthermore, multivariate analysis showed that lung cancer patients whose blood IGFBP2 was higher had a poor survival outcome, with a hazard ratio of 8.22 (95%CI 1.78-37.92, P = 0.007) after adjustment for stage, histopathology, EGFR mutation, age, smoking and surgery.

Topics: Adenocarcinoma; Autophagy; Carcinoma, Non-Small-Cell Lung; Carcinoma, Squamous Cell; Case-Control Studies; Drug Resistance, Neoplasm; Female; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Insulin-Like Growth Factor Binding Protein 2; Lung Neoplasms; Male; Middle Aged; Prognosis; Retrospective Studies; Survival Rate; Tumor Cells, Cultured

Radiotherapy is used to treat tumors of different origins and nature, but often lead to development of radioresistance and metastasis of cells. Interestingly, radiation induces epithelial-mesenchymal transition (EMT), a process by which epithelial cells undergo mesenchymal phenotype and stimulates tumor progression capability. Our study investigated the effect of Trichostatin A (TSA), a natural derivate isolated from Streptomyces, upon radiation-induced lung EMT and we tried to understand the role of signaling molecules in irradiated lung cancer cells (A549). The cells were categorized into four groups: untreated control, radiation alone (R; 8Gy, X-ray), radiation combined with TSA (R + T) and TSA (100nM). Radiation-induced lung EMT were evidenced by decreased expression of epithelial marker like E-cadherin, Zona occluden1 (ZO-1) and increased expression of N-cadherin and Vimentin. The Snail protein, a master regulator of EMT, was observed to be elevated after radiation treatment. In addition, TGF-β1 signaling (smad2, 3, and 4) proteins were activated upon irradiation. Western blot data were supported by the altered m-RNA expression of E-cadherin, TGF-β and Snail genes and this effect were reversed by TSA treatment. In addition to this, as supportive evidence, we performed docking studies between snail protein and TSA using Auto docking software and results suggested that less binding energy was needed for the putative binding of TSA on C-terminal domain of Snail protein. Based on our report, we suggest that TSA can effectively inhibit radiation-induced EMT (i) by altering epithelial and mesenchymal markers (ii) by modulating signaling molecules of TGFβ1 pathway (iii) by inhibiting cancer cell migratory potential in A549 cells (iv)by effectively binding to Snail which is an enhancer of EMT.

Topics: A549 Cells; Cell Movement; Epithelial-Mesenchymal Transition; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung Neoplasms; RNA, Messenger; RNA, Neoplasm; Signal Transduction; Smad Proteins; Snail Family Transcription Factors; Transforming Growth Factor beta; Zinc Finger E-box-Binding Homeobox 1

Claudin-2 is highly expressed in lung adenocarcinoma tissues and increases proliferation in adenocarcinoma cells. The chemicals that reduce claudin-2 expression may have anti-cancer effects, but such therapeutic medicines have not been developed. We found that azacitidine (AZA), a DNA methylation inhibitor, and trichostatin A (TSA) and sodium butyrate (NaB), histone deacetylase (HDAC) inhibitors, decrease claudin-2 levels. The effect of AZA was mediated by the inhibition of phosphorylated Akt and NF-κB. LY-294002, an inhibitor of phosphatidylinositol 3-kinase (PI3K), and BAY 11-7082, an NF-κB inhibitor, decreased claudin-2 levels. The reporter activity of claudin-2 was decreased by AZA and LY-294002, which was blocked by the mutation in a putative NF-κB-binding site. NF-κB bound to the promoter region of claudin-2, which was inhibited by AZA and LY-294002. AZA is suggested to decrease the claudin-2 mRNA level mediated by the inhibition of a PI3K/Akt/NF-κB pathway. TSA and NaB did not change phosphorylated Akt and NF-κB levels. Furthermore, these inhibitors did not change the reporter activity of claudin-2 but decreased the stability of claudin-2 mRNA mediated by the elevation of miR-497 microRNA. The binding of histone H3 to the promoter region of miR-497 was inhibited by TSA and NaB, whereas that of claudin-2 was not. These results suggest that HDAC inhibitors decrease claudin-2 levels mediated by the elevation of miR-497 expression. Cell proliferation was additively decreased by AZA, TSA, and NaB, which was partially rescued by ectopic expression of claudin-2. We suggest that epigenetic inhibitors suppress the abnormal proliferation of lung adenocarcinoma cells highly expressing claudin-2.

Topics: A549 Cells; Adenocarcinoma; Adenocarcinoma of Lung; Azacitidine; Butyric Acid; Cell Proliferation; Chromones; Claudin-2; Down-Regulation; Epigenesis, Genetic; Humans; Hydroxamic Acids; Lung Neoplasms; MicroRNAs; Morpholines; Nitriles; RNA, Messenger; Signal Transduction; Sulfones

Genistein has been shown to enhance the antitumor activity of trichostatin A (TSA) in human lung carcinoma A549 cells. However, whether the combined treatment exerts the same effect in other lung cancer cells is unclear. In the present study we first compared the enhancing effect of genistein on the antitumor effect of TSA in ABC-1, NCI-H460 (H460) and A549 cells. Second, we investigated whether the effects of genistein are associated with increased histone/non-histone protein acetylation. We found that the enhancing effect of genistein on cell-growth-arrest in ABC-1 cells (p53 mutant) was less than in A549 and H460 cells. Genistein enhanced TSA induced apoptosis in A549 and H460 cells rather than in ABC-1 cells. After silencing p53 expression in A549 and H460 cells, the enhancing effect of genistein was diminished. In addition, genistein increased TSA-induced histone H3/H4 acetylation in A549 and H460 cells. Genistein also increased p53 acetylation in H460 cells. The inhibitor of acetyltransferase, anacardic acid, diminished the enhancing effect of genistein on all TSA-induced histone/p53 acetylation and apoptosis. Genistein in combination with TSA increased the expression of p300 protein, an acetyltransferase, in A549 and NCI-H460 cells. Furthermore, we demonstrated that genistein also enhanced the antitumor effect of genistein in A549-tumor-bearing mice. Taken together, these results suggest that the enhancing effects of genistein on TSA-induced apoptosis in lung cancer cells were p53-dependent and were associated with histone/non-histone protein acetylation.

Topics: Animals; Apoptosis; Cell Line, Tumor; Dose-Response Relationship, Drug; Drug Synergism; Genes, p53; Genistein; Histone Acetyltransferases; Humans; Hydroxamic Acids; Lung Neoplasms; Mice; Mice, Nude; Up-Regulation; Xenograft Model Antitumor Assays

The adenovirus vector-based cancer gene therapy is controversial. Low transduction efficacy is believed to be one of the main barriers for the decreased expression of coxsackie and adenovirus receptor (CAR) on tumor cells. However, the expression of CAR on primary tumor tissue and tumor tissue survived from treatment has still been not extensively studied. The present study analyzed the adenovirus infection rates and CAR expression in human lung adenocarcinoma cell line A549 and its cisplatin-resistant subline A549/DDP. The results showed that although the CAR expression in A549 and A549/DDP was not different, compared with the A549, A549/DDP appeared obviously to reject adenovirus infection. Moreover, we modified CAR expression in the two cell lines with proteasome inhibitor MG-132 and histone deacetylase inhibitor trichostatin A (TSA), and analyzed the adenovirus infection rates after modifying agent treatments. Both TSA and MG-132 pretreatments could increase the CAR expression in the two cell lines, but the drug pretreatments could only make A549 cells more susceptible to adenovirus infectivity.

Topics: A549 Cells; Adenocarcinoma; Adenocarcinoma of Lung; Adenoviridae; Adenoviridae Infections; Cell Line, Tumor; Cisplatin; Coxsackie and Adenovirus Receptor-Like Membrane Protein; Drug Resistance, Neoplasm; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Leupeptins; Lung Neoplasms; Proteasome Inhibitors

Recent studies indicated undisputed contribution of connective tissue growth factor (CTGF) in the development of many cancers, including non-small cell lung cancer (NSCLC). However, the functional role and regulation of CTGF expression during tumorigenesis remain elusive. Our goal was to determine CTGF transcript and protein levels in tumoral and matched control tissues from 98 NSCLC patients, to correlate the results with clinicopathological features and to investigate whether the CTGF expression can be epigenetically regulated in NSCLC.. We used quantitative PCR, Western blotting and immunohistochemistry to evaluate CTGF expression in lung cancerous and histopathologically unchanged tissues. We tested the impact of 5-Aza-2'-deoxycytidine (5-dAzaC) and trichostatin A (TSA) on CTGF transcript and protein levels in NSCLC cells (A549, Calu-1). DNA methylation status of the CTGF regulatory region was evaluated by bisulfite sequencing. The influence of 5-dAzaC and TSA on NSCLC cells viability and proliferation was monitored by the trypan blue assay.. We found significantly decreased levels of CTGF mRNA and protein (both p < 0.0000001) in cancerous tissues of NSCLC patients. Down-regulation of CTGF occurred regardless of gender in all histological subtypes of NSCLC. Moreover, we showed that 5-dAzaC and TSA were able to restore CTGF mRNA and protein contents in NSCLC cells. However, no methylation within CTGF regulatory region was detected. Both compounds significantly reduced NSCLC cells proliferation.. Decreased expression of CTGF is a common feature in NSCLC; however, it can be restored by the chromatin-modifying agents such as 5-dAzaC or TSA and consequently restrain cancer development.

Topics: Adult; Aged; Aged, 80 and over; Azacitidine; Biomarkers, Tumor; Carcinoma, Non-Small-Cell Lung; Connective Tissue Growth Factor; Decitabine; DNA Methylation; Down-Regulation; Epigenesis, Genetic; Female; Gene Expression Regulation, Neoplastic; HeLa Cells; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung Neoplasms; Male; Middle Aged; Prognosis; Promoter Regions, Genetic; Tumor Cells, Cultured

Non-small-cell lung cancer (NSCLC) is the leading cause of cancer-related death worldwide. NSCLC development and progression have recently been correlated with the heightened activation of histone deacetylases (HDACs) and PI3K/Akt signaling pathways. Targeted inhibition of these proteins is promising approach for the development of novel therapeutic strategies to treat patients with advanced NSCLC. For this reason, we combined a dual PI3K and mTOR inhibitor, BEZ235 with the HDAC inhibitor Trichostatin A (TSA), to determine their combined effects on human NSCLC. In this study, we initially discovered that co-treatment with BEZ235 and TSA showed a synergistic effect on inhibition of NSCLC cell proliferation and induction of apoptosis. The combination treatment also synergistically suppressed NSCLC migration, invasion and the NSCLC epithelial-mesenchymal transition (EMT) in vitro. The synergistic effect was also evidenced by declines in xenograft growth and metastasis rates and in ki-67 protein expression in vivo. Together, these results indicated that BEZ235 and TSA combination treatment significantly increased anti-tumor activities compared with BEZ235 and TSA alone, supporting a further evaluation of combination treatment for NSCLC.

Topics: A549 Cells; Animals; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Cell Proliferation; Drug Synergism; Female; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Imidazoles; Lung Neoplasms; Mice, Inbred BALB C; Mice, Nude; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Quinolines; TOR Serine-Threonine Kinases; Treatment Outcome; Xenograft Model Antitumor Assays

Lung cancer is clearly the primary cause of cancer-related deaths worldwide. Recent molecular-targeted strategy has contributed to improvement of the curative effect of adenocarcinoma of the lung. However, such current treatment has not been developed for squamous cell carcinoma (SCC) of the disease. The new genome-wide RNA analysis of lung-SCC may provide new avenues for research and the development of the disease. Our recent microRNA (miRNA) expression signatures of lung-SCC revealed that clustered miRNAs miR-1/133a were significantly reduced in cancer tissues. Here, we found that restoration of both mature miR-1 and miR-133a significantly inhibited cancer cell proliferation, migration and invasion. Coronin-1C (CORO1C) was a common target gene of the miR-1/133a cluster, as shown by the genome-wide gene expression analysis and the luciferase reporter assay. Silencing of CORO1C gene expression inhibited cancer cell proliferation, migration and invasion. Furthermore, CORO1C-regulated molecular pathways were categorized by using si-CORO1C transfectants. Further analysis of novel cancer signaling pathways modulated by the tumor-suppressive cluster miR-1/133a will provide insights into the molecular mechanisms of lung-SCC oncogenesis and metastasis.

Topics: Aged; Aged, 80 and over; Azacitidine; Blotting, Western; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Movement; Cell Proliferation; Down-Regulation; Enzyme Inhibitors; Female; Gene Expression Regulation, Neoplastic; Humans; Hydroxamic Acids; Lung Neoplasms; Male; Microfilament Proteins; MicroRNAs; Middle Aged; Multigene Family; Neoplasm Invasiveness; Reverse Transcriptase Polymerase Chain Reaction; RNA Interference

Lung cancer cells show inherent and acquired resistance to chemotherapy. The lack of good predictive markers/novel targets and the incomplete understanding of the mechanisms of resistance limit the success of lung cancer response to chemotherapy. In the present study, we used an isogenic pair of lung adenocarcinoma cell lines; A549 (wild-type) and A549DOX11 (doxorubicin resistant) to study the role of epigenetics and miRNA in resistance/response of non-small cell lung cancer (NSCLC) cells to doxorubicin. Our results demonstrate differential expression of epigenetic markers whereby the level of HDACs 1, 2, 3 and4, DNA methyltransferase, acetylated H2B and acetylated H3 were lower in A549DOX11 compared to A549 cells. Fourteen miRNAs were dys-regulated in A549DOX11 cells compared to A549 cells, of these 14 miRNAs, 4 (has-mir-1973, 494, 4286 and 29b-3p) have shown 2.99 - 4.44 fold increase in their expression. This was associated with reduced apoptosis and higher resistance of A549DOX11cells to doxorubicin and etoposide. Sequential treatment with the epigenetic modifiers trichostatin A or 5-aza-2'-deoxycytidine followed by doxorubicin resulted in: (i) enhanced sensitivity of both cell lines to doxorubicin especially at low concentrations, (ii) enhanced doxorubicin-induced DNA damage in both cell lines, (iii) dysregulation of some miRNAs in A549 cells. In conclusion, A549DOX11 cells resistant to DNA damaging drugs have epigenetic profile and miRNA expression different from the sensitive cells. Moreover, epigenetic modifiers may reverse the resistance of certain NSCLC cells to DNA damaging agents by enhancing induction of DNA damage. This may open the door for using epigenetic profile/miRNA expression of some cancer cells as resistance markers/targets to improve response of resistant cells to doxorubicin and for the use of combination doxorubicin/epigenetic modifiers to reduce doxorubicin toxicity.

Topics: Antibiotics, Antineoplastic; Azacitidine; Biomarkers, Tumor; Blotting, Western; Cell Line, Tumor; Cell Survival; Decitabine; DNA Methylation; DNA Modification Methylases; Doxorubicin; Drug Resistance, Neoplasm; Epigenesis, Genetic; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Histone Deacetylase Inhibitors; Histone Deacetylases; Humans; Hydroxamic Acids; Lung Neoplasms; MicroRNAs; Oligonucleotide Array Sequence Analysis; Reverse Transcriptase Polymerase Chain Reaction

Trichostatin A (TSA) is a histone deacetylase inhibitor and a potential therapeutic for various malignancies. The in vivo effect of TSA, however, has not been investigated in a transgenic lung cancer model. Previously, we generated transgenic mice with overexpression of Groucho-related-gene 1 (Grg1) and these mice all developed mucinous lung adenocarcinoma. Grg1 is a transcriptional co-repressor protein, the function of which is thought to depend on HDAC activity. However, functions outside the nucleus have also been proposed. We tested the supposition that Grg1-induced tumorigenesis is HDAC-dependent by assaying the therapeutic effect of TSA in the Grg1 transgenic mouse model. We found that TSA significantly inhibited lung tumorigenesis in Grg1 transgenic mice (p < 0.01). TSA did not affect overall Grg1 protein levels, but instead reduced ErbB1 and ErbB2 expression, which are upregulated by Grg1 in the absence of TSA. We confirmed this effect in A549 cells. Furthermore, lapatinib, an inhibitor of both ErbB1 and ErbB2, effectively masked the effect of TSA on the inhibition of A549 cell proliferation and migration, suggesting TSA does work, at least in part, by downregulating ErbB receptors. We additionally found that TSA reduced the expression of VEGF and VEGFR2, but not basic FGF and FGFR1. Our findings indicate that TSA effectively inhibits Grg1-induced lung tumorigenesis through the down-regulation of ErbB1 and ErbB2, as well as reduced VEGF signaling. This suggests TSA and other HDAC inhibitors could have therapeutic value in the treatment of lung cancers with Grg1 overexpression.

Topics: Adenocarcinoma; Animals; Cell Line, Tumor; Co-Repressor Proteins; Genes, erbB-1; Genes, erbB-2; Humans; Hydroxamic Acids; Lung Neoplasms; Mice; Mice, Transgenic

To evaluate the potential therapeutic utility of histone deacetylase inhibitors (HDACi) in targeting VEGF receptors in non-small-cell lung cancer.. Non-small-cell lung cancer cells were screened for the VEGF receptors at the mRNA and protein levels, while cellular responses to various HDACi were examined.. Significant effects on the regulation of the VEGF receptors were observed in response to HDACi. These were associated with decreased secretion of VEGF, decreased cellular proliferation and increased apoptosis which could not be rescued by addition of exogenous recombinant VEGF. Direct remodeling of the VEGFR1 and VEGFR2 promoters was observed. In contrast, HDACi treatments resulted in significant downregulation of the Neuropilin receptors.. Epigenetic targeting of the Neuropilin receptors may offer an effective treatment for lung cancer patients in the clinical setting.

Topics: Acetylation; Apoptosis; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Cell Proliferation; Cell Survival; Chromatin Assembly and Disassembly; Epigenesis, Genetic; Gene Expression Regulation, Neoplastic; Histone Deacetylase Inhibitors; Histones; Humans; Hydroxamic Acids; Lung Neoplasms; Molecular Targeted Therapy; Receptors, Vascular Endothelial Growth Factor; Vascular Endothelial Growth Factor A; Vorinostat

DNA methylation plays a critical role during the development of acquired chemoresistance. The aim of this study was to identify candidate DNA methylation drivers of cisplatin (DDP) resistance in non-small cell lung cancer (NSCLC). The A549/DDP cell line was established by continuous exposure of A549 cells to increasing concentrations of DDP. Gene expression and methylation profiling were determined by high-throughput microarrays. Relationship of methylation status and DDP response was validated in primary tumor cell culture and the Cancer Genome Atlas (TCGA) samples. Cell proliferation, apoptosis, cell cycle, and response to DDP were determined in vitro and in vivo. A total of 372 genes showed hypermethylation and downregulation in A549/DDP cells, and these genes were involved in most fundamental biological processes. Ten candidate genes (S100P, GDA, WISP2, LOXL1, TIMP4, ICAM1, CLMP, HSP8, GAS1, BMP2) were selected, and exhibited varying degrees of association with DDP resistance. Low dose combination of 5-aza-2'-deoxycytidine (5-Aza-dC) and trichostatin A (TSA) reversed drug resistance of A549/DDP cells in vitro and in vivo, along with demethylation and restoration of expression of candidate genes (GAS1, TIMP4, ICAM1 and WISP2). Forced expression of GAS1 in A549/DDP cells by gene transfection contributed to increased sensitivity to DDP, proliferation inhibition, cell cycle arrest, apoptosis enhancement, and in vivo growth retardation. Together, our study demonstrated that a panel of candidate genes downregulated by DNA methylation induced DDP resistance in NSCLC, and showed that epigenetic therapy resensitized cells to DDP.

Topics: Antimetabolites, Antineoplastic; Antineoplastic Agents; Apoptosis; Azacitidine; Carcinoma, Non-Small-Cell Lung; Cell Cycle Checkpoints; Cell Cycle Proteins; Cell Line, Tumor; Cell Proliferation; Cisplatin; Decitabine; DNA Methylation; Drug Resistance, Neoplasm; Epigenesis, Genetic; Gene Expression Profiling; GPI-Linked Proteins; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung Neoplasms; RNA, Messenger

This study describes the sensitization mechanism to thermal stress by histone deacetylase inhibitors (HDACIs) in lung cancer cells and shows that Ku70, based on its acetylation status, mediates the protection of lung cancer from hyperthermia (42.5°C, 1-6 hrs). Ku70 regulates apoptosis by sequestering pro-apoptotic Bax. However, its role in thermal stress is not fully understood. The findings showed that, pre-treating lung cancer cells with HDACIs, nicotinamide (NM) or Trichostatin A (TsA) or both significantly enhanced hyperthermia-induced Bax-dependent apoptosis in PC-10 cells. We found that hyperthermia induces SirT-1, Sirtuin, upregulation but not HDAC6 or SirT-3, therefore transfection with dominant negative SirT-1 (Y/H) also eliminated the protection and resulted in more cell death by hyperthermia, in H1299 cells through Bax activation. Hyperthermia alone primed lung cancer cells to apoptosis without prominent death. After hyperthermia Bax was upregulated, Bcl-2 was downregulated, the Bax/Bcl-2 ratio was inversed and Bax/Bcl-2 heterodimer was dissociated. Although hyperthermia did not affect total Ku70 expression level, it stimulated Ku70 deacetylation, which in turn could bind more Bax in the PC-10 cells. These findings suggest an escape mechanism from hyperthermia-induced Bax activation. To verify the role of Ku70 in this protection mechanism, Ku70 was silenced by siRNA. Ku70 silencing significantly sensitized the lung cancer cells to hyperthermia. The Ku70 KD cells underwent cytotoxic G1 arrest and caspase-dependant apoptosis when compared to scrambled transfectants which showed only G2/M cytostatic arrest in the cell lines investigated, suggesting an additional cell cycle-dependent, novel, role of Ku70 in protection from hyperthermia. Taken together, our data show a Ku70-dependent protection mechanism from hyperthermia. Targeting Ku70 and/or its acetylation during hyperthermia may represent a promising therapeutic approach for lung cancer.

Topics: Antigens, Nuclear; Apoptosis; bcl-2-Associated X Protein; Cell Death; Cell Line, Tumor; DNA-Binding Proteins; Histone Deacetylase Inhibitors; Hot Temperature; Humans; Hydroxamic Acids; Hyperthermia, Induced; Ku Autoantigen; Lung Neoplasms; Niacinamide

RASSF1C is a major isoform of the RASSF1 gene, and is emerging as an oncogene. This is in contradistinction to the RASSF1A isoform, which is an established tumor suppressor. We have previously shown that RASSF1C promotes lung cancer cell proliferation and have identified RASSF1C target genes with growth promoting functions. Here, we further report that RASSF1C promotes lung cancer cell migration and enhances lung cancer cell tumor sphere formation. We also show that RASSF1C over-expression reduces the inhibitory effects of the anti-cancer agent, betulinic acid (BA), on lung cancer cell proliferation. In previous work, we demonstrated that RASSF1C up-regulates piwil1 gene expression, which is a stem cell self-renewal gene that is over-expressed in several human cancers, including lung cancer. Here, we report on the effects of BA on piwil1 gene expression. Cells treated with BA show decreased piwil1 expression. Also, interaction of IGFBP-5 with RASSF1C appears to prevent RASSF1C from up-regulating PIWIL1 protein levels. These findings suggest that IGFBP-5 may be a negative modulator of RASSF1C/ PIWIL1 growth-promoting activities. In addition, we found that inhibition of the ATM-AMPK pathway up-regulates RASSF1C gene expression.

Topics: Antineoplastic Agents; Argonaute Proteins; beta Catenin; Betulinic Acid; Cell Movement; Cell Proliferation; Drug Resistance, Neoplasm; Gene Expression; Gene Expression Regulation, Neoplastic; Humans; Hydroxamic Acids; Insulin-Like Growth Factor Binding Protein 5; Lung Neoplasms; Pentacyclic Triterpenes; Pyrazoles; Pyrimidines; Signal Transduction; Spheroids, Cellular; Triterpenes; Tumor Suppressor Proteins

The istone deacetylase (HDAC) inhibitor trichostatin A (TSA) is known to mediate the regulation of gene expression and anti proliferation activity in cancer cells. Kruppel-like factor 4 (klf4) is a zinc finger- containing transcription factor of the SP/KLF family, that is expressed in a variety of tissues and regulates cell proliferation, differentiation, tumorigenesis, and apoptosis. It may either either function as a tumor suppressor or an oncogene depending on genetic context of tumors.. In this study, we tested the possibility that TSA may increase klf4 expression and cancer cell growth inhibition and apoptosis in SKOV-3 and A549 cells.. The cytotoxicity of TSA was determined using the MTT assay test, while klf4 gene expression was assessed by real time PCR and to ability of TSA to induce apoptosis using a Vybrant Apoptosis Assay kit.. Our results showed that TSA exerted dose and time dependent cytotoxicity effect on SKOV-3 and A549 cells. Moreover TSA up-regulated klf4 expression. Flow cytometric analysis demonstrated that apoptosis was increased after TSA treatment.. Taken together, this study showed that TSA increased klf4 expression in SKOV3 and A549 cell lines, consequently, klf4 may played a tumor-suppressor role by increasing both cell growth inhibition and apoptosis. This study sheds light on the details of molecular mechanisms of HDACI-induced cell cycle arrest and apoptosis.

Topics: Apoptosis; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Female; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Kruppel-Like Factor 4; Kruppel-Like Transcription Factors; Lung Neoplasms; Ovarian Neoplasms; Up-Regulation

Cytoglobin (CYGB) is frequently downregulated in many types of human malignancies, and its exogenous overexpression reduces proliferation of cancer cells. Despite its implied tumour suppressor (TSG) functions, its exact role in carcinogenesis remains unclear as CYGB upregulation is also associated with tumour hypoxia and aggressiveness. In this study, we explore the TSG role of CYGB, its influence on the phenotype of cancerous cells under stress conditions and the clinical significance of CYGB expression and promoter methylation in non-small cell lung cancer (NSCLC). DNA methylation-dependent expression silencing of CYGB is demonstrated in both clinical samples and cell lines. CYGB promoter was more frequently methylated in lung adenocarcinomas (P = 1.4 × 10(-4)). Demethylation by 5'-azadeoxycytidine partially restored CYGB expression in cell lines. Interestingly, trichostatin A triggered upregulation of CYGB expression in cancer cell lines and downregulation in non-tumourigenic ones. CYGB mRNA expression in NSCLC surgical specimens correlated with that of HIF1α and VEGFa (P < 1 × 10(-4)). Overexpression of CYGB in cancer cell lines reduced cell migration, invasion and anchorage-independent growth. Moreover, CYGB impaired cell proliferation, but only in the lung adenocarcinoma cell line (H358). Upon hydrogen peroxide treatment, CYGB protected cell viability, migratory potential and anchorage independence by attenuating oxidative injury. In hypoxia, CYGB overexpression decreased cell viability, augmented migration and anchorage independence in a cell-type-specific manner. In conclusion, CYGB revealed TSG properties in normoxia but promoted tumourigenic potential of the cells exposed to stress, suggesting a bimodal function in lung tumourigenesis, depending on cell type and microenvironmental conditions.

Topics: Adenocarcinoma; Adenocarcinoma of Lung; Carcinoma, Non-Small-Cell Lung; Cell Hypoxia; Cell Line, Tumor; Cytoglobin; DNA Methylation; Gene Expression Regulation, Neoplastic; Gene Silencing; Genes, Tumor Suppressor; Globins; Humans; Hydroxamic Acids; Hypoxia-Inducible Factor 1, alpha Subunit; Lung Neoplasms; Oncogenes; Vascular Endothelial Growth Factor A

Small cell lung cancer (SCLC) accounts for nearly 15% of human lung cancers and is one of the most aggressive solid tumors. The SCLC cells are thought to derive from self-renewing pulmonary neuroendocrine cells by oncogenic transformation. However, whether the SCLC cells possess stemness and plasticity for differentiation as normal stem cells has not been well understood thus far. In this study, we investigated the expressions of multilineage stem cell markers in the cancer cells of SCLC cell line (NCI-H446) and analyzed their clonogenicity, tumorigenicity, and plasticity for inducing differentiation. It has been found that most cancer cells of the cell line expressed multilineage stem cell markers under the routine culture conditions and generated single-cell clones in anchorage-dependent or -independent conditions. These cancer cells could form subcutaneous xenograft tumors and orthotopic lung xenograft tumors in BALB/C-nude mice. Most cells in xenograft tumors expressed stem cell markers and proliferation cell nuclear antigen Ki67, suggesting that these cancer cells remained stemness and highly proliferative ability in vivo. Intriguingly, the cancer cells could be induced to differentiate into neurons, adipocytes, and osteocytes, respectively, in vitro. During the processes of cellular phenotype-conversions, autophagy and apoptosis were two main metabolic events. There is cross-talking between autophagy and apoptosis in the differentiated cancer cells. In addition, the effects of the inhibitor and agonist for Sirtuin1/2 on the inducing osteogenic differentiation indicated that Sirtuin1/2 had an important role in this process. Taken together, these results indicate that most cancer cells of NCI-H446 cell line possess stemness and plasticity for multilineage differentiation. These findings have potentially some translational applications in treatments of SCLC with inducing differentiation therapy.

Topics: Adipogenesis; Animals; Apoptosis; Autophagy; Cell Differentiation; Cell Line, Tumor; Cell Lineage; Cell Transformation, Neoplastic; Humans; Hydroxamic Acids; Ki-67 Antigen; Lung Neoplasms; Mice; Mice, Nude; Neoplastic Stem Cells; Neurogenesis; Osteogenesis; Sirtuin 1; Sirtuin 2; Small Cell Lung Carcinoma; Transplantation, Heterologous

Histone deacetylases (HDACs) inhibitor is a promising new approach to the treatment of lung cancer therapy via inhibiting cell growth and inducing apoptosis. miR-15a and miR-16-1 are important tumor suppressors through modulating B cell lymphoma 2 (Bcl-2), Cyclin D1, D2, and others. However, whether HDACs inhibitor modulates the expression of miR-15a/16-1 in lung cancer is still unknown. The purpose of our study was to identify a new miRNA-mediated mechanism which plays an important role in the anti-cancer effects of HDACs inhibitor. We found HDACs inhibitors trichostatin A (TSA) and sodium butyrate upregulated the expression of miR-15a/16-1, residing in the host tumor suppressor Dleu2 gene, through increasing the histone acetylation in the region of Dleu2/miR-15a/16-1 promoter in lung cancer cells. Moreover, among class Ι HDACs subtypes, only knockdown of HDAC3 by specific siRNA increased the hyperacetylation of Dleu2/miR-15a/16-1 promoter region and finally resulted in the upregulation of miR-15a/16-1. Furthermore, overexpression of miR-15a/16-1, which were always deleted or downregulated in lung cancer cells, effectively suppressed cell growth and reduced colony formation. Finally, TSA reduced the expression of Bcl-2, an important survival protein in lung cancer cells, partly through upregulation of miR-15a/16-1. Therefore, this offers a therapeutic strategy that lung cancer patients who exhibit low level of miR-15a/16-1 or high activity of HDACs may benefit from HDACs inhibitor-based therapy.

Topics: Acetylation; Apoptosis; Butyric Acid; Carcinoma, Non-Small-Cell Lung; Cell Cycle Checkpoints; Cell Line, Tumor; Cell Proliferation; Down-Regulation; Gene Expression Regulation, Neoplastic; Gene Knockdown Techniques; Histone Deacetylase Inhibitors; Histone Deacetylases; Histones; Humans; Hydroxamic Acids; Lung Neoplasms; MicroRNAs; Promoter Regions, Genetic; Proto-Oncogene Proteins c-bcl-2; RNA, Long Noncoding; Transferases; Tumor Stem Cell Assay; Tumor Suppressor Proteins; Up-Regulation

PUMA is a crucial regulator of apoptotic cell death mediated by p53-dependent and p53-independent mechanisms. In many cancer cells, PUMA expression is induced in response to DNA-damaging reagent in a p53-dependent manner. However, few studies have investigated transcription factors that lead to the induction of PUMA expression via p53-independent apoptotic signaling. In this study, we found that the transcription factor Sox4 increased PUMA expression in response to trichostatin A (TSA), a histone deacetylase inhibitor in the p53-null human lung cancer cell line H1299. Ectopic expression of Sox4 led to the induction of PUMA expression at the mRNA and protein levels, and TSA-mediated up-regulation of PUMA transcription was repressed by the knockdown of Sox4. Using luciferase assays and chromatin immunoprecipitation, we also determined that Sox4 recruits p300 on the PUMA promoter region and increases PUMA gene expression in response to TSA treatment. Taken together, these results suggest that Sox4 is required for p53-independent apoptotic cell death mediated by PUMA induction via TSA treatment.

Topics: Apoptosis; Apoptosis Regulatory Proteins; Cell Line, Tumor; Cell Survival; Dose-Response Relationship, Drug; Gene Expression Regulation, Enzymologic; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung Neoplasms; Promoter Regions, Genetic; Protein Structure, Tertiary; Proto-Oncogene Proteins; SOXC Transcription Factors; Transcription, Genetic; Tumor Suppressor Protein p53

Prostaglandin E2 (PGE2) is an important pro-angiogenic and pro-proliferative cytokine and the key enzymes modulating its levels, cyclooxygenase (COX)-2 and 15-hydroxyprostaglandin dehydrogenase (15-PGDH) play important opposing roles in carcinogenesis. Previously we found loss of 15-PGDH expression in lung cancer and its reactivation leads to strong in vivo tumor-suppressive effect via an antiangiogenic mechanism. Here, we find that HDAC inhibitors (HDACI), such as trichostatin A (TSA) and vorinostat could reactivate 15-PGDH expression but overall induce PGE2 generation and this is the result of concomitant induction of COX-1 and -2 leading to functional promotion of endothelial cell proliferation and capillary formation. Direct TSA treatment inhibits endothelial cell proliferation and capillary formation in our study in line with prior reports as HDACIs have been shown to directly inhibit angiogenesis. The elevation of PGE2 levels induced by HDACI is potently neutralized by indomethacin (INN) or Celecoxib co-treatment and accordingly, angiogenesis is more effectively inhibited when using conditioned medium of co-treatment than either alone confirming that this effect is mediated via the PGE2 axis. Accordingly, blockage of EP2/4 receptors mitigates the stimulation of angiogenesis by excessive PGE2 generation mediated by TSA. In this study, we identify a potentially adverse effect of HDACIs through induction of both 15-PGDH and COX-2 leading to elevated PGE2 levels and thereby stimulation of angiogenesis. Co-treatment of TSA and INN shows more potent anti-angiogenic effects by inducing 15-PGDH and inhibiting COX-2. Overall, our results suggest that combined HDACI and COX inhibition should be explored clinically to achieve more meaningful benefits from HDACI therapy in lung cancer.

Topics: Angiogenesis Inhibitors; Celecoxib; Cell Line, Tumor; Cyclooxygenase 1; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Cyclooxygenase Inhibitors; Dinoprostone; Drug Synergism; Epithelial Cells; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Hydroxyprostaglandin Dehydrogenases; Indomethacin; Lung Neoplasms; Pyrazoles; Sulfonamides; Vorinostat

Coxsackie adenovirus receptor (CAR) is the primary receptor to which oncolytic adenoviruses have to bind for internalization and viral replication. A total of 171 neuroendocrine lung tumors in form of multitissue arrays have been analyzed resulting in a positivity of 112 cases (65.5%). Immunostaining correlated statistically significant with histopathology and development of recurrence. The subtype small cell lung cancer (SCLC) showed the highest CAR expression (77.6%), moreover the CAR level was correlated to the disease-free survival. Further, high CAR expression level in SCLC cell lines was found in vitro and in vivo when cell lines had been transplanted into immunodeficient mice. A correlation between CAR expression in the primary tumors and metastases development in the tumor model underlined the clinical relevance. Cell lines with high CAR level showed a high infectivity when infected with a replication-deficient adenovirus. Low levels of CAR expression in SCLC could be upregulated with Trichostatin A, a histone deacetylase inhibitor. As a result of the unaltered poor prognosis of SCLC and its high CAR expression it seems to be the perfect candidate for oncolytic therapy. With our clinically relevant tumor model, we show that xenograft experiments are warrant to test the efficiency of oncolytic adenoviral therapy.

Topics: Adenoviridae; Animals; Cell Line, Tumor; Coxsackie and Adenovirus Receptor-Like Membrane Protein; Female; Gene Expression; Green Fluorescent Proteins; Humans; Hydroxamic Acids; Kaplan-Meier Estimate; Lung Neoplasms; Male; Mice; Neuroendocrine Tumors; Oncolytic Virotherapy; Oncolytic Viruses; Proportional Hazards Models; Small Cell Lung Carcinoma; Xenograft Model Antitumor Assays

Histone deacetylase inhibitors can regulate gene expression through modulation of the degree of acetylation of histone and non-histone, thus affecting cell proliferation, survival and chemosensitivity. Histone deacetylase inhibitors combined with paclitaxel may enhance the inhibitory effect of drugs on lung cancer cells. This study aimed to observe the effect of trichostatin A (TSA)/paclitaxel on the proliferation and apoptosis in human A549 lung adenocarcinoma cells, and to investigate its mechanism.. A549 cells were cultured in Dulbecco modified Eagle's medium (DMEM) in the presence of paclitaxel and the histone deacetylase inhibitor TSA, and the growth curve was obtained by trypan-blue exclusion assay and cell count. Apoptosis was assessed using Hoechst 33258 staining and flow cytometry analysis, and cell cycle was detected by flow cytometry analysis. The proteins poly ADP-ribose polymerase (PARP), caspase-3, survivin, and tubulin acetylation were detected by Western blotting.. A significant reduction of proliferation was observed in A549 lung adenocarcinoma cells treated by paclitaxel or TSA. Combined treatment with TSA/paclitaxel caused the greatest inhibition of cell proliferation. The combined treatment with TSA and paclitaxel induced more severe apoptosis, and significantly more cells were arrested in G2/M phase (P < 0.05) then with a single drug. Using Western blotting, we demonstrated that treatment with TSA/paclitaxel led to synergistic increase in acetylated tubulin, PARP, caspase-3, and reduced the expression of survivin.. TSA and paclitaxel have a synergistic activity that can inhibit cell growth and induce apoptosis.

Topics: Acetylation; Adenocarcinoma; Adenocarcinoma of Lung; Antineoplastic Agents, Phytogenic; Apoptosis; Caspase 3; Cell Line, Tumor; Cell Proliferation; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung Neoplasms; Paclitaxel; Tubulin

This study investigated the effects of quercetin on the anti-tumor effect of trichostatin A (TSA), a novel anticancer drug, in vitro and in vivo and the possible mechanisms of these effects in human lung cancer cells. We first showed that quercetin (5 µM) significantly increased the growth arrest and apoptosis in A549 cells (expressing wild-type p53) induced by 25 ng/mL of (82.5 nM) TSA at 48 h by about 25% and 101%, respectively. However, such enhancing effects of quercetin (5 µM) were not significant in TSA-exposed H1299 cells (a p53 null mutant) or were much lower than in A549 cells. In addition, quercetin significantly increased TSA-induced p53 expression in A549 cells. Transfection of p53 siRNA into A549 cells significantly but not completely diminished the enhancing effects of quercetin on TSA-induced apoptosis. Furthermore, we demonstrated that quercetin enhanced TSA-induced apoptosis through the mitochondrial pathway. Transfection of p53 siRNA abolished such enhancing effects of quercetin. However, quercetin increased the acetylation of histones H3 and H4 induced by TSA in A549 cells, even with p53 siRNA transfection as well as in H1299 cells. In a xenograft mouse model of lung cancer, quercetin enhanced the antitumor effect of TSA. Tumors from mice treated with TSA in combination with quercetin had higher p53 and apoptosis levels than did those from control and TSA-treated mice. These data indicate that regulation of the expression of p53 by quercetin plays an important role in enhancing TSA-induced apoptosis in A549 cells. However, p53-independent mechanisms may also contribute to the enhancing effect of quercetin.

Topics: Animals; Antineoplastic Agents; Apoptosis; Cell Line, Tumor; Humans; Hydroxamic Acids; Lung Neoplasms; Male; Mice; Mice, Nude; Quercetin; Tumor Suppressor Protein p53

Src has a role in the anoikis resistance in lung adenocarcinomas. We focused on two epidermal growth factor receptor (EGFR)-mutant lung adenocarcinoma cell lines, HCC827 (E746-A750 deletion) and H1975 (L858R+T790M), in suspension to elucidate whether suspended lung adenocarcinoma cells are eradicated by long-term treatment with Src tyrosine kinase inhibitors (TKIs). We also examined metastasis-positive lymph nodes from 16 EGFR-mutant lung adenocarcinoma patients for immunohistochemical expression of mutant-specific EGFR. Almost all suspended HCC827 cells underwent apoptosis after 144 h of combination treatment with AZD0530, trichostatin A (TSA), and ABT-263, whereas many suspended H1975 cells survived the treatment. AZD0530 is a Src TKI, TSA is a histone deacetylase inhibitor, and ABT-263 is a Bcl-2 inhibitor. During the therapy, the phosphorylation of EGFR decreased in HCC827 cells and remained stable in H1975 cells. The phosphorylated EGFR of Src TKI-resistant H1975 cells, as well as HCC827 cells, was completely suppressed by the third generation EGFR TKI, WZ4002. Consequently, both the suspended cell lines were almost completely eradicated within 144 h, with the combined therapy of WZ4002, ABT-263, and TSA. Interestingly, treated suspended cells underwent apoptosis to a greater extent than did adherent cells. Intrasinus floating lung adenocarcinoma cells in the lymph nodes expressed a mutant-specific EGFR. These findings suggest that suspended EGFR-mutant lung adenocarcinoma cells depend significantly more on EGFR activation for survival than attached cells do. The tumor cells circulating in vessels, which express mutant-specific EGFR, would be highly susceptible to the combination therapy of WZ4002, ABT-263, and TSA.

Topics: Acrylamides; Adenocarcinoma; Aged; Aged, 80 and over; Aniline Compounds; Anoikis; Benzodioxoles; Cell Line, Tumor; Drug Evaluation, Preclinical; Drug Therapy, Combination; ErbB Receptors; Female; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung Neoplasms; Male; Middle Aged; Phosphorylation; Proto-Oncogene Proteins c-bcl-2; Pyrimidines; Quinazolines; src-Family Kinases; Sulfonamides

The major aim of this study was to investigate the role of DNA methylation (referred to as methylation) on miRNA silencing in non-small cell lung cancers (NSCLC).. We conducted microarray expression analyses of 856 miRNAs in NSCLC A549 cells before and after treatment with the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine (Aza-dC) and with a combination of Aza-dC and the histone deacetylase inhibitor trichostatin A. miRNA methylation was determined in 11 NSCLC cell lines and in primary tumors and corresponding nonmalignant lung tissue samples of 101 patients with stage I-III NSCLC.. By comparing microarray data of untreated and drug-treated A549 cells, we identified 33 miRNAs whose expression was upregulated after drug treatment and which are associated with a CpG island. Thirty (91%) of these miRNAs were found to be methylated in at least 1 of 11 NSCLC cell lines analyzed. Moreover, miR-9-3 and miR-193a were found to be tumor specifically methylated in patients with NSCLC. We observed a shorter disease-free survival of patients with miR-9-3 methylated lung squamous cell carcinoma (LSCC) than patients with miR-9-3 unmethylated LSCC by multivariate analysis [HR = 3.8; 95% confidence interval (CI), 1.3-11.2, P = 0.017] and a shorter overall survival of patients with miR-9-3 methylated LSCC than patients with miR-9-3 unmethylated LSCC by univariate analysis (P = 0.013).. Overall, our results suggest that methylation is an important mechanism for inactivation of certain miRNAs in NSCLCs and that miR-9-3 methylation may serve as a prognostic parameter in patients with LSCC.

Topics: Antineoplastic Agents; Azacitidine; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Decitabine; DNA Methylation; Female; Gene Expression Profiling; Gene Silencing; Humans; Hydroxamic Acids; Lung; Lung Neoplasms; Male; MicroRNAs; Middle Aged; Molecular Targeted Therapy; Oligonucleotide Array Sequence Analysis

Our previous study has shown that genistein enhances apoptosis in A549 lung cancer cells induced by trichostatin A (TSA). The precise molecular mechanism underlying the effect of genistein, however, remains unclear. In the present study, we investigated whether genistein enhances the anti-cancer effect of TSA through up-regulation of TNF receptor-1 (TNFR-1) death receptor signaling. We incubated A549 cells with TSA (50 ng/mL) alone or in combination with genistein and then determined the mRNA and protein expression of TNFR-1 as well as the activation of downstream caspases. Genistein at 5 and 10 μM significantly enhanced the TSA-induced decrease in cell number and apoptosis in a dose-dependent manner. The combined treatment significantly increased mRNA and protein expression of TNFR-1 at 6 and 12h, respectively, compared with that of the control group; while TSA alone had no effect. TSA in combination with 10 μM of genistein increased TNFR-1 mRNA and protein expression by about 70% and 40%, respectively. The underlying mechanism for this effect of genistein may be partly associated with the estrogen receptor pathway. The combined treatment also increased the activation of caspase-3 and -10 as well as p53 protein expression in A549 cells. The enhancing effects of genistein on the TSA-induced decrease in cell number and on the expression of caspase-3 in A549 cells were suppressed by silencing TNFR-1 expression. These data demonstrated that the upregulation of TNFR-1 death receptor signaling plays an important role, at least in part, in the enhancing effect of genistein on TSA-induced apoptosis in A549 cells.

Topics: Apoptosis; Blotting, Western; Carcinoma, Non-Small-Cell Lung; Caspases; Cell Line, Tumor; Dose-Response Relationship, Drug; Drug Synergism; Genistein; Humans; Hydroxamic Acids; Lung Neoplasms; Receptors, Tumor Necrosis Factor, Type I; Reverse Transcriptase Polymerase Chain Reaction; RNA, Small Interfering; Up-Regulation

To investigate the effect of trichostatin A (TSA)/paclitaxel on the growth and apoptosis in human lung adenocarcinoma cell line A549 cells.. Human lung adenocarcinoma A549 cells were cultured in DMEM in the presence of paclitaxel and the histone deacetylase inhibitor trichostatin A, and the growth curve was obtained by trypan-blue exclusion assay and cell count. Apoptosis was assessed using Hoechst 33258 staining and flow cytometry, and cell cycle was detected by flow cytometry analysis. The proteins of PARP, caspase-3, survivin and tubulin acetylation were detected by Western blotting.. Significant growth reduction was observed in the A549 cells following treatment with paclitaxel or the histone deacetylase inhibitor TSA. The combined treatment with TSA/paclitaxel caused the highest inhibition of cell growth. The apoptosis rate of A549 cells treated with TSA or paclitaxel for 24 hours was (17.6 ± 1.8)% and (39.2 ± 3.7)%, respectively, but a significantly higher apoptosis rate was (64.2 ± 4.2)% was induced by combined treatment with TSA and paclitaxel. In contrast with the control group, the cell cycle was markedly arrested at G2/M phase in the TSA and paclitaxel group (P < 0.05). The Western blot analysis demonstrated that treatment with TSA/paclitaxel led to a synergistic increase of acetylated tubulin, PARP and caspase-3, and reduced the expression of survivin.. TSA or paclitaxel alone can inhibit the cell growth and induce apoptosis, and the combination of TSA and paclitaxel exerts a synergistic effect on the growth and apoptosis in lung adenocarcinoma cells.

Topics: Acetylation; Adenocarcinoma; Antineoplastic Agents, Phytogenic; Apoptosis; Caspase 3; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Drug Synergism; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Inhibitor of Apoptosis Proteins; Lung Neoplasms; Paclitaxel; Poly(ADP-ribose) Polymerases; Survivin; Tubulin; Tubulin Modulators

Histone deacetylase (HDAC) inhibitors represent a promising class of potential anticancer agents for treatment of human malignancies. In this study, we investigated the effect of trichostatin A (TSA), one such HDAC inhibitor, in combination with docetaxel (TXT), a cytotoxic chemotherapy agent or erlotinib, a novel molecular target therapy drug, on lung cancer A549 cells.. A549 cells were treated with TXT, erlotinib alone or in combination with TSA, respectively. Cell viability, apoptosis, and cell cycle distribution were evaluated using MTT (3- (4, 5-dimethylthiazol-2-yl) -2, 5-diphenyltetrazolium bromide) assay, Hochst33258 staining and flow cytometry. Moreover, immunofluorescent staining and Western blot analysis were employed to examine alterations of α-tubulin, heat shock protein 90 (hsp90), epidermal growth factor receptor (EGFR), and caspase-3 in response to the different exogenous stimuli.. Compared with single-agent treatment, co-treatment of A549 cells with TSA/TXT or TSA/erlotinib synergistically inhibited cell proliferation, induced apoptosis, and caused cell cycle delay at the G2/M transition. Treatment with TSA/TXT or TSA/erlotinib led to a significant increase of cleaved caspase-3 expression, also resulting in elevated acetylation of α-tubulin or hsp90 and decreased expression of EGFR, which was negatively associated with the level of acetylated hsp90.. Synergistic anti-tumor effects are observed between TXT or erlotinib and TSA on lung cancer cells. Such combinations may provide a more effective strategy for treating human lung cancer.

Topics: Acetylation; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Caspase 3; Cell Division; Cell Line, Tumor; Cell Proliferation; Cell Survival; Docetaxel; Drug Synergism; ErbB Receptors; Erlotinib Hydrochloride; G2 Phase; Histone Deacetylase Inhibitors; HSP90 Heat-Shock Proteins; Humans; Hydroxamic Acids; Lung Neoplasms; Quinazolines; Taxoids; Tubulin

Cisplatin-based chemotherapy is the standard therapy used to treat non-small-cell lung cancer. However, its efficacy is largely limited due to the development of drug resistance. The exact mechanism in which cancer cells develop resistance to the drug is not yet fully understood. The purpose of the present study is to test the role of volume-sensitive Cl(-) channels in cisplatin resistance in human lung adenocarcinoma cells (A549 cells) using patch-clamp recording, cell volume measurement and apoptosis assay. The results showed that cisplatin treatment induced an apoptotic volume decrease (AVD) and activated a Cl(-) current that showed properties similar to the volume-sensitive outward rectifying (VSOR) Cl(-) current in wild-type A549 cells. Both the AVD process and VSOR Cl(-) current were blocked by the chloride channel blocker 4,4'-diisothiocyanostilbene-2,2' disulfonic acid. However, the A549/CDDP cells, a model of acquired cisplatin resistance cells, on the other hand, had almost no AVD process and VSOR Cl(-) current when treated with cisplatin. Treatment of A549/CDDP cells with trichostatin A (TSA), a drug that inhibits histone deacetylases, partially restored the VSOR Cl(-) current and increased cisplatin-induced cell apoptosis rate. These results suggest that impaired activity of VSOR Cl(-) channels contributes to the cisplatin resistance in A549/CDDP cells.

Topics: Adenocarcinoma; Antineoplastic Agents; Apoptosis; Base Sequence; Cell Line, Tumor; Chloride Channels; Cisplatin; DNA Primers; Drug Resistance, Neoplasm; Humans; Hydroxamic Acids; Lung Neoplasms; Patch-Clamp Techniques; Reverse Transcriptase Polymerase Chain Reaction

Lung cancer is the leading cause of cancer-related mortality and requires more effective molecular markers of prognosis and therapeutic responsiveness. Special AT-rich binding protein 1 (SATB1) is a global genome organizer that recruits chromatin remodeling proteins to epigenetically regulate hundreds of genes in a tissue-specific manner. Initial studies suggest that SATB1 overexpression is a predictor of poor prognosis in breast cancer, but the prognostic significance of SATB1 expression has not been evaluated in lung cancer.. A cohort of 257 lung cancers was evaluated by immunohistochemistry. Epigenetic silencing of SATB1 was examined in cell lines by 5-Aza 2-deoxycytidine and trichostatin A treatment, and chromatin immunoprecipitation.. Significant loss of SATB1 expression was found in squamous preinvasive lesions (p < 0.04) and in non-small cell lung cancers (p < 0.001) compared with matched normal bronchial epithelium. Loss of SATB1 independently predicted poor cancer-specific survival in squamous cell carcinomas (SCCs; hazard ratio: 2.06, 95% confidence interval: 1.2-3.7, p = 0.016). Treatment of lung cancer cell lines with the histone deacetylase inhibitor trichostatin A resulted in up-regulation of SATB1. SATB1 was associated with a decrease in the active chromatin mark acetylated histone H3K9 and an increase in the repressive polycomb mark trimethylated H3K27 in a SCC cell line relative to a normal bronchial epithelial cell line.. This is the first study showing that SATB1 expression is lost in early preinvasive squamous lesions and that loss of SATB1 is associated with poor prognosis in lung SCC. We hypothesize that the SATB1 gene is epigenetically silenced through histone modifications.

Topics: Adenocarcinoma; Adult; Aged; Aged, 80 and over; Antimetabolites, Antineoplastic; Azacitidine; Blotting, Western; Carcinoma, Large Cell; Carcinoma, Non-Small-Cell Lung; Carcinoma, Squamous Cell; Cell Line, Tumor; Chromatin Immunoprecipitation; Cohort Studies; Decitabine; DNA Methylation; Epigenesis, Genetic; Female; Follow-Up Studies; Gene Expression Regulation, Neoplastic; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Immunoenzyme Techniques; Lung Neoplasms; Male; Matrix Attachment Region Binding Proteins; Middle Aged; Neoplasm Staging; Prognosis; Tissue Array Analysis

Histone deacetylase inhibitors (HDACIs) induce growth arrest and apoptosis in cancer cells. In addition to their intrinsic anticancer properties, HDACIs modulate cellular responses to ionizing radiation (IR). We examined the molecular mechanism(s) associated with the radiosensitizing effects of HDACIs in human lung cancer cells.. Lung cancer cells were pretreated with the appropriate concentrations of suberoylanilide hydroxamic acid or trichostatin A. After 2 hours, cells were irradiated with various doses of γ-IR, and then we performed 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, fluorescence-activated cell sorting analysis, clonogenic assay, and Western blotting to detect cell viability or apoptosis and changes of specific proteins expression levels.. In this study, we showed that HDACIs (including suberoylanilide hydroxamic acid and trichostatin A) and IR synergistically trigger cell death in human non-small cell lung cancer cells. Cell viability and clonogenic survival were markedly decreased in cultures cotreated with HDACIs and IR. Interestingly, p53 acetylation at lysine 382 was significantly increased, and c-myc expression simultaneously down-regulated in cotreated cells. Radiosensitization by HDACIs was inhibited on transfection with small interfering RNA against p53 and c-myc overexpression, supporting the involvement of p53 and c-myc in this process. Furthermore, c-myc down-regulation and apoptotic cell death coinduced by IR and HDACI were suppressed in cells transfected with mutant K382R p53 and C135Y p53 displaying loss of acetylation at lysine 382 and DNA-binding activity, respectively.. Our results collectively demonstrate that the degree of radiosensitization by HDACIs is influenced by acetyl p53-mediated c-myc down-regulation.

Topics: Acetylation; Apoptosis; Blotting, Western; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Cell Proliferation; Combined Modality Therapy; Down-Regulation; Flow Cytometry; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung Neoplasms; Membrane Potential, Mitochondrial; Mutagenesis, Site-Directed; Mutation; Proto-Oncogene Proteins c-myc; Radiation-Sensitizing Agents; Radiation, Ionizing; Tumor Suppressor Protein p53; Vorinostat

Tumor cells are characterized by accelerated growth usually accompanied by up-regulated pathways that ultimately increase the rate of ATP production. These cells can suffer metabolic reprogramming, resulting in distinct bioenergetic phenotypes, generally enhancing glycolysis channeled to lactate production. In the present work we showed metabolic reprogramming by means of inhibitors of histone deacetylase (HDACis), sodium butyrate and trichostatin. This treatment was able to shift energy metabolism by activating mitochondrial systems such as the respiratory chain and oxidative phosphorylation that were largely repressed in the untreated controls.. Various cellular and biochemical parameters were evaluated in lung cancer H460 cells treated with the histone deacetylase inhibitors (HDACis), sodium butyrate (NaB) and trichostatin A (TSA). NaB and TSA reduced glycolytic flux, assayed by lactate release by H460 cells in a concentration dependent manner. NaB inhibited the expression of glucose transporter type 1 (GLUT 1), but substantially increased mitochondria bound hexokinase (HK) activity. NaB induced increase in HK activity was associated to isoform HK I and was accompanied by 1.5 fold increase in HK I mRNA expression and cognate protein biosynthesis. Lactate dehydrogenase (LDH) and pyruvate kinase (PYK) activities were unchanged by HDACis suggesting that the increase in the HK activity was not coupled to glycolytic flux. High resolution respirometry of H460 cells revealed NaB-dependent increased rates of oxygen consumption coupled to ATP synthesis. Metabolomic analysis showed that NaB altered the glycolytic metabolite profile of intact H460 cells. Concomitantly we detected an activation of the pentose phosphate pathway (PPP). The high O(2) consumption in NaB-treated cells was shown to be unrelated to mitochondrial biogenesis since citrate synthase (CS) activity and the amount of mitochondrial DNA remained unchanged.. NaB and TSA induced an increase in mitochondrial function and oxidative metabolism in H460 lung tumor cells concomitant with a less proliferative cellular phenotype.

Topics: Butyrates; Cell Cycle; Cell Differentiation; Cell Line, Tumor; Cell Membrane Permeability; Cell Proliferation; Cell Respiration; Cell Shape; Energy Metabolism; Glucose 1-Dehydrogenase; Glucose Transporter Type 1; Glucose Transporter Type 3; Glycolysis; Hexokinase; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; L-Lactate Dehydrogenase; Lactates; Lung Neoplasms; Mitochondria; Protein Binding; Pyruvate Kinase; Succinate Dehydrogenase

Lung carcinogenesis in humans involves an accumulation of genetic and epigenetic changes that lead to alterations in normal lung epithelium, to in situ carcinoma, and finally to invasive and metastatic cancers. The loss of transforming growth factor β (TGF-β)-induced tumor suppressor function in tumors plays a pivotal role in this process, and our previous studies have shown that resistance to TGF-β in lung cancers occurs mostly through the loss of TGF-β type II receptor expression (TβRII). However, little is known about the mechanism of down-regulation of TβRII and how histone deacetylase (HDAC) inhibitors (HDIs) can restore TGF-β-induced tumor suppressor function. Here we show that HDIs restore TβRII expression and that DNA hypermethylation has no effect on TβRII promoter activity in lung cancer cell lines. TGF-β-induced tumor suppressor function is restored by HDIs in lung cancer cell lines that lack TβRII expression. Activation of mitogen-activated protein kinase/extracellular signal-regulated kinase pathway by either activated Ras or epidermal growth factor signaling is involved in the down-regulation of TβRII through histone deacetylation. We have immunoprecipitated the protein complexes by biotinylated oligonucleotides corresponding to the HDI-responsive element in the TβRII promoter (-127/-75) and identified the proteins/factors using proteomics studies. The transcriptional repressor Meis1/2 is involved in repressing the TβRII promoter activity, possibly through its recruitment by Sp1 and NF-YA to the promoter. These results suggest a mechanism for the downregulation of TβRII in lung cancer and that TGF-β tumor suppressor functions may be restored by HDIs in lung cancer patients with the loss of TβRII expression.

Topics: Animals; Blotting, Western; Butadienes; CCAAT-Binding Factor; Cell Line, Tumor; Enzyme Inhibitors; Gene Expression Regulation, Neoplastic; Histone Deacetylase Inhibitors; Homeodomain Proteins; Humans; Hydroxamic Acids; Lung Neoplasms; MAP Kinase Signaling System; Mice; Mice, Inbred BALB C; Mice, Nude; Mitogen-Activated Protein Kinases; Nitriles; Promoter Regions, Genetic; Protein Binding; Protein Serine-Threonine Kinases; Receptor, Transforming Growth Factor-beta Type II; Receptors, Transforming Growth Factor beta; Reverse Transcriptase Polymerase Chain Reaction; Sp1 Transcription Factor; Transcription Factors; Transforming Growth Factor beta; Transplantation, Heterologous

Cisplatin-based chemotherapy is the paradigm of non-small-cell lung cancer (NSCLC) treatment; however, it also induces de novo DNA-hypermethylation, a process that may be involved in the development of drug-resistant phenotypes by inactivating genes required for drug-cytotoxicity. By using an expression microarray analysis, we aimed to identify those genes reactivated in a set of two cisplatin (CDDP) resistant and sensitive NSCLC cell lines after epigenetic treatment. Gene expression, promoter methylation and CDDP-chemoresponse were further analyzed in three matched sets of sensitive/resistant cell lines, 23 human cancer cell lines and 36 NSCLC specimens. Results revealed specific silencing by promoter hypermethylation of IGFBP-3 in CDDP resistant cells, whereas IGFBP-3 siRNA interference, induced resistance to CDDP in sensitive cells (P<0.001). In addition, we found a strong correlation between methylation status and CDDP response in tumor specimens (P<0.001). Thus, stage I patients, whose tumors harbor an unmethylated promoter, had a trend towards increased disease-free survival (DFS). We report that a loss of IGFBP-3 expression, mediated by promoter-hypermethylation, results in a reduction of tumor cell sensitivity to cisplatin in NSCLC. Basal methylation status of IGFBP-3 before treatment may be a clinical biomarker and a predictor of the chemotherapy outcome, helping to identify patients who are most likely to benefit from CDDP therapy alone or in combination with epigenetic treatment.

Topics: Antineoplastic Agents; Azacitidine; Base Sequence; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Cell Survival; Cisplatin; DNA Methylation; Drug Resistance, Neoplasm; Gene Expression Regulation, Neoplastic; HeLa Cells; HT29 Cells; Humans; Hydroxamic Acids; Insulin-Like Growth Factor Binding Protein 3; Kaplan-Meier Estimate; Lung Neoplasms; Oligonucleotide Array Sequence Analysis; Promoter Regions, Genetic; Reverse Transcriptase Polymerase Chain Reaction; RNA Interference; Tumor Cells, Cultured

To investigate the apoptosis-inducing effect of trichostatin A (TSA) in the human lung adenocarcinoma cisplatin-resistant cell line (A549/CDDP) and to examine whether TSA can enhance sensitivity to cisplatin treatment and the underlying molecular mechanisms of such an enhancement.. Cell viability was evaluated using the Neutral Red assay. Apoptosis was assessed using Hoechst 33258 staining and flow cytometry analysis. Protein expression was detected by Western blotting. To determine the role of Death-associated protein kinase (DAPK) in TSA-induced apoptosis in the A549/CDDP cell line, cells were transfected with pcDNA3.1(+)-DAPK, which has a higher expression level of DAPK compared to endogenous expression, and DAPK activity was inhibited by both over-expression C-terminal fragment of DAPK which may competitive binding DAPK substrates to inhibit the function of DAPK and RNA interference.. TSA induced apoptosis in both A549 cells and A549/CDDP cells. TSA enhanced the sensitivity of A549/CDDP cells to cisplatin, along with concomitant DAPK up-regulation. When DAPK was over-expressed, A549/CDDP cells became sensitive to cisplatin and the cytotoxicity of TSA could be increased. Moreover, the cytotoxicity of TSA could be alleviated by inhibition of DAPK activity by the expression of a recombinant C-terminal fragment of DAPK or RNA interference.. TSA induced sensitivity to cisplatin treatment in cisplatin-resistant A549 cells. The up-regulation of DAPK is one of the mechanisms mediating sensitization to TSA-induced apoptosis in cisplatin-resistant cells.

Topics: Adenocarcinoma; Antineoplastic Agents; Apoptosis; Apoptosis Regulatory Proteins; Calcium-Calmodulin-Dependent Protein Kinases; Cell Line, Tumor; Cell Survival; Cisplatin; Death-Associated Protein Kinases; Drug Resistance, Neoplasm; Humans; Hydroxamic Acids; Lung Neoplasms; Protein Synthesis Inhibitors; Up-Regulation

To explore the effect of trichostatin A (TSA) on human lung cancer cell strains A549.. A549 cells were exposed to TSA at different concentrations, then the growth-inhibiting effects of the cell line were detected with 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay; After the cells were exposed to TSA for 48 and 96 hours at 300 nmol/L, the change of the cell cycle and apoptosis of A549 were analyzed with flow cytometry. p21 protein and extracellular signal regulated kinase (ERK) expression were detected by Western blot.. TSA inhibited the growth of A549 cells in time- and concentration-dependent manners. The proportion of apoptosis, G0/G1 and G2/M phase increased in accordance with raising of the TSA concentration. The expression of p21 protein was significantly up-regulated and the expression of phosphorylation ERK was significantly down-regulated after A549 cells were treated with TSA.. Histone deacetylase inhibitor TSA can inhibit the proliferation of human lung cancer cell strains A549 and induce the cell cycle arrest and apoptosis in the A549 cells. This may be related to up-regulation of p21 protein expression and the down-regulation of phosphorylation ERK.

Topics: Adenocarcinoma; Adenocarcinoma of Lung; Apoptosis; Cell Cycle; Cell Line, Tumor; Extracellular Signal-Regulated MAP Kinases; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung Neoplasms

The imaging analytical capabilities of laser scanning cytometer (LSC) have been used to assess morphological features considered to be typical of the senescent phenotype. The characteristic "flattening" of senescent cells was reflected by the decline in the density of staining (intensity of maximal pixel) of DNA-associated fluorescence [4,6-diamidino-2-phenylindole (DAPI)] paralleled by an increase in nuclear size (area). The decrease in ratio of maximal pixel to nuclear area was even more sensitive senescence biomarker than the change in maximal pixel or nuclear area, each alone. The saturation cell density at plateau phase of growth recorded by LSC was found to be dramatically decreased in cultures of senescent cells, thereby also serving as an additional marker. The induction of cyclin dependent kinase inhibitors p21(WAF1) and p27(KIP1) and γH2AX and activation of ATM markers of DNA damage response were measured in parallel with DNA/DAPI maximal pixel and nuclear area. These biomarker indices were expressed in quantitative terms by reporting them as a fraction of the respective controls. The effect of treatment of A549 and WI-38 cells with different concentrations of mitoxantrone (Mxt) and trichostatin A for various time periods was studied to assess the degree (depth) of cell senescence. Also assessed was the effect of 2-deoxy-D-glucose, the agent attenuating metabolic cell activity, on the depth of senescence induced by Mxt. A relationship between the ability of cells to synthesize RNA (incorporate 5-ethynyluridine) that leads to growth imbalance and induction of cell senescence was also studied. The data show that morphometric analysis of cellular attributes by LSC offers an attractive tool to detect cell senescence and measure its degree particularly in assessing effects of the factors that enhance or attenuate this process. This methodology is of importance in light of the evidence that cellular senescence is not only a biological process that is fundamental for organismal aging but also impedes formation of induced-pluripotent stem cells providing the barrier for neoplastic transformation and is the major mechanism of induction of reproductive cell death during treatment of solid tumors.

Topics: Adenocarcinoma; Apoptosis; beta-Galactosidase; Biomarkers; Cell Count; Cell Line, Tumor; Cell Nucleus; Cellular Senescence; Cyclin-Dependent Kinase Inhibitor p21; Cyclin-Dependent Kinase Inhibitor p27; Fibroblasts; Fluorescent Dyes; Histones; Humans; Hydroxamic Acids; Indoles; Intracellular Signaling Peptides and Proteins; Laser Scanning Cytometry; Lung Neoplasms; Mitoxantrone

Histone deacetylase (HDAC) inhibitors (HDIs) play an important role in the regulation of gene expression associated with cell cycle and apoptosis and have emerged as promising anticancer agents. In addition to their intrinsic anticancer properties, some studies have demonstrated that HDIs can modulate cellular responses to ionizing radiation (IR). Here we show evidence that co-treatment with the HDI trichostatin A (TSA) radiosensitizes human non-small cell lung cancer (NSCLC) A549 cells and H1650 cells. Cells were exposed to gamma-irradiation with or without TSA co-treatment. Clonogenic survival was significantly reduced in cells with TSA co-treatment. In A549 cells, TSA enhanced IR-induced accumulation of cells in G(2)/M phase, with upregulated expression of p21(waf1/cip1). In addition, TSA co-treatment caused pronounced apoptosis in irradiated cells, which was accompanied with p21(waf1/cip1) cleavage to a 15 kDa protein. The enhanced apoptotic effect was via mitochondrial pathway, as indicated by the increased dissipation of mitochondrial transmembrane potential (MMP) and release of cytochrome c from the mitochondria to the cytoplasm. Caspase-3 activation was also significantly increased, with accordingly more cleavage of PARP, associated with the repression of X-linked inhibitor of apoptosis protein (XIAP). Furthermore, TSA co-treatment impaired DNA repair capacity after IR by downregulation of Ku70, Ku80 and DNA-PKcs, reflected by enhanced and prolonged expression of gammaH2AX. Taken together, our results demonstrate that TSA acts as a powerful radiosensitizer in NSCLC cells by enhancing G(2)/M cell cycle arrest, promoting apoptosis through multiple pathways and interfering with DNA damage repair processes.

Topics: Apoptosis; Carcinoma, Non-Small-Cell Lung; Caspase 3; Cell Cycle; Cell Line, Tumor; Combined Modality Therapy; DNA Repair; Dose-Response Relationship, Drug; Dose-Response Relationship, Radiation; Down-Regulation; Histone Deacetylase Inhibitors; Histone Deacetylases; Humans; Hydroxamic Acids; Lung Neoplasms; Membrane Potential, Mitochondrial; Radiation Dosage; Radiation Tolerance; Radiation-Sensitizing Agents

Topics: Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Non-Small-Cell Lung; Drug Screening Assays, Antitumor; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung Neoplasms; Tumor Cells, Cultured; Vorinostat

Early metastasis is a hallmark of pancreatic ductal adenocarcinoma and responsible for >90% of pancreatic cancer death. Because little is known about the biology and genetics of the metastatic process, we desired to elucidate molecular pathways mediating pancreatic cancer metastasis in vivo by an unbiased forward genetic approach.. Highly metastatic pancreatic cancer cell populations were selected by serial in vivo passaging of parental cells with low metastatic potential and characterized by global gene expression profiling, chromatin immunoprecipitation, and in vivo metastatic assay.. In vivo selection of highly metastatic pancreatic cancer cells induced epithelial-mesenchymal transition (EMT), loss of E-cadherin expression, and up-regulation of mesenchymal genes such as Snail. Genetic inactivation of E-cadherin in parental cells induced EMT and increased metastasis in vivo. Silencing of E-cadherin in highly metastatic cells is mediated by a transcriptional repressor complex containing Snail and histone deacetylase 1 (HDAC1) and HDAC2. In line, mesenchymal pancreatic cancer specimens and primary cell lines from genetically engineered Kras(G12D) mice showed HDAC-dependent down-regulation of E-cadherin and high metastatic potential. Finally, transforming growth factor beta-driven E-cadherin silencing and EMT of human pancreatic cancer cells depends on HDAC activity.. We provide the first in vivo evidence that HDACs and Snail play an essential role in silencing E-cadherin during the metastatic process of pancreatic cancer cells. These data link the epigenetic HDAC machinery to EMT and metastasis and provide preclinical evidence that HDACs are promising targets for antimetastatic therapy.

Topics: Animals; Antigens, CD; Antineoplastic Agents; Cadherins; Cell Line, Tumor; Cell Transdifferentiation; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Gene Silencing; Histone Deacetylase 1; Histone Deacetylase 2; Histone Deacetylase Inhibitors; Histone Deacetylases; Humans; Hydroxamic Acids; Lung Neoplasms; Mice; Mice, Nude; Pancreatic Neoplasms; Promoter Regions, Genetic; Repressor Proteins; RNA Interference; Snail Family Transcription Factors; Transcription Factors; Transfection

Cyclooxygenase (COX)-2 is frequently overexpressed in non-small cell lung cancer (NSCLC) and results in increased levels of prostaglandin E2 (PGE(2)), an important signalling molecule implicated in tumourigenesis. PGE(2) exerts its effects through the E prostanoid (EP) receptors (EPs1-4).. The expression and epigenetic regulation of the EPs were evaluated in a series of resected fresh frozen NSCLC tumours and cell lines.. EP expression was dysregulated in NSCLC being up and downregulated compared to matched control samples. For EPs1, 3 and 4 no discernible pattern emerged. EP2 mRNA however was frequently downregulated, with low levels being observed in 13/20 samples as compared to upregulation in 5/20 samples examined. In NSCLC cell lines DNA CpG methylation was found to be important for the regulation of EP3 expression, the demethylating agent decitabine upregulating expression. Histone acetylation was also found to be a critical regulator of EP expression, with the histone deacteylase inhibitors trichostatin A, phenylbutyrate and suberoylanilide hydroxamic acid inducing increased expression of EPs2-4. Direct chromatin remodelling was demonstrated at the promoters for EPs2-4.. These results indicate that EP expression is variably altered from tumour to tumour in NSCLC. EP2 expression appears to be predominantly downregulated and may have an important role in the pathogenesis of the disease. Epigenetic regulation of the EPs may be central to the precise role COX-2 may play in the evolution of individual tumours.

Topics: Acetylation; Antineoplastic Agents; Azacitidine; Carcinoma, Non-Small-Cell Lung; Cell Proliferation; Chromatin Assembly and Disassembly; CpG Islands; Decitabine; DNA Methylation; Epigenesis, Genetic; Gene Expression Regulation, Neoplastic; Histone Deacetylase Inhibitors; Histones; Humans; Hydroxamic Acids; Lung Neoplasms; Phenylbutyrates; Receptors, Prostaglandin E; RNA, Messenger; Tumor Cells, Cultured; Vorinostat

We recently identified that DNA methylation of the G0S2 gene was significantly more frequent in squamous lung cancer than in non-squamous lung cancer. However, the significance of G0S2 methylation levels on cancer cells is not yet known. We investigated the effect of G0S2 methylation levels on cell growth, mRNA expression, and chromatin structure using squamous lung cancer cell lines and normal human bronchial epithelial cells. DNA methylation and mRNA expression of G0S2 were inversely correlated, and in one of the squamous lung cancer cell lines, LC-1 sq, G0S2 was completely methylated and suppressed. Overexpression of G0S2 in LC-1 sq did not show growth arrest or apoptosis. The G0S2 gene has been reported to be a target gene of all-trans retinoic acid and peroxisome proliferator-activated receptor agonists. We treated LC-1 sq with 5-Aza-2'-deoxycytidine, Trichostatin A, all-trans retinoic acid, Wy 14643, or Pioglitazone either alone or in combination. Only 5-Aza-2'-deoxycytidine restored mRNA expression of G0S2. Chromatin immunoprecipitation revealed that histone H3 lysine 9 was methylated regardless of DNA methylation or mRNA expression. In summary, mRNA expression of G0S2 was regulated mainly by DNA methylation in squamous lung cancer cell lines. When the G0S2 gene was methylated, nuclear receptor agonists could not restore mRNA expression of G0S2 and did not show any additive effect on mRNA expression of G0S2 even after the treatment with 5-Aza-2'-deoxycytidine.

Topics: Azacitidine; Cell Cycle Proteins; Cell Line, Tumor; Chromatin Immunoprecipitation; Decitabine; DNA Methylation; DNA Modification Methylases; Gene Expression Regulation, Neoplastic; Humans; Hydroxamic Acids; Lung Neoplasms; Neoplasms, Squamous Cell; Peroxisome Proliferator-Activated Receptors; Pioglitazone; Thiazolidinediones; Transcription, Genetic; Tretinoin

Histone deacetylase (HDAC) inhibitors can inhibit cell signal network function through decreasing expression of multiple genes and proteins, thus affect cell proliferation, survival and chemosensitivity. HDAC inhibitors combined with paclitaxel may enhance the inhibitory effect of drugs on lung cancer cells. This study was to observe the synergistic anti-proliferative effect of HDAC inhibitor trichostatin A (TSA) combined with paclitaxel on lung cancer cell lines H322 and H1299, and to investigate its mechanism.. H322 and H1299 cells were divided into control group, paclitaxel (TAX) group, TSA group, and combination group (TF group, TSA followed by paclitaxel). Cell proliferation was determined by MTT assay. Cell cycle and apoptosis were determined by flow cytometry. The protein expression levels of survivin, ERK, and PARP were determined by Western blot analysis.. When combined with TSA, the 50% inhibition concentration (IC50) of paclitaxel decreased from (48.07+/-26.12) nmol/L to (6.34+/-5.72) nmol/L in H322 cells and from (110.6+/-38.7) nmol/L to (63.7+/-11.8) nmol/L in H1299 cells, with significant differences (P<0.05). Apoptosis rate of H322 cells was higher in the the TF group than in the TAX group(P<0.05). There were more necrosis cells in the TF group of H1299 cell line than in the other groups. pERK was up-regulated in the TAX group of H322 cell line. Expression of Survivin was up-regulated in the TAX group of two cells. Expressions of Survivin and pERK were down-regulated in the TSA and TF groups of two cell lines. Cleaved PARP was detected in the TAX and the TF groups of H322 cells, and its expression was significantly higher in the the TF group than in the TAX group. Cleaved PARP was not detected in each group of H1299 cells.. TSA combined with paclitaxel has a synergistic cytotoxicity effect on lung cancer cell lines H322 and H1299 when the cells were treated with TSA followed by paclitaxel. The mechanism may be that TSA down-regulates the survivin high-expression induced by paclitaxel, and blocks pERK protein expression.

Topics: Antineoplastic Agents, Phytogenic; Apoptosis; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Drug Synergism; Extracellular Signal-Regulated MAP Kinases; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Inhibitor of Apoptosis Proteins; Lung Neoplasms; Paclitaxel; Phosphorylation; Poly(ADP-ribose) Polymerases; Survivin

Loss of E-cadherin confers a poor prognosis in lung cancer patients and is associated with in vitro resistance to endothelial growth factor receptor inhibitors. Zinc finger E box-binding homeobox (ZEB)-1, the predominant transcriptional suppressor of E-cadherin in lung tumor lines, recruits histone deacetylases (HDACs) as co-repressors.. NSCLC cell lines were treated with HDAC inhibitors and analyzed for E-cadherin induction, growth inhibition and apoptosis. National Cancer Institute-H157 cells expressing ectopic E-cadherin were tested for tumorigenicity in murine xenografts.. We found that treatment with MS-275, compared to vorinostat (SAHA), valproic acid or trichostatin A, was most effective in E-cadherin up-regulation and persistence in non-small cell lung cancers. As with other tumor types and HDAC inhibitors, MS-275 inhibited growth and induced apoptosis. Importantly, blocking E-cadherin induction by short hairpin RNA resulted in less inhibition by MS-275, implicating the epithelial to mesenchymal phenotype process as a contributing factor. In contrast to H460 and H661, H157 cells were resistant to E-cadherin up-regulation by HDAC inhibitors. However, E-cadherin was restored, in a synergistic manner, by combined knockdown of ZEB-1 and ZEB-2. In addition, H157 cells stably transfected with E-cadherin were markedly attenuated in their tumor forming ability. Lastly, combining MS-275 with the microtubule stabilizing agent, paclitaxel, or 17-(allylamino)-17-demethoxygeldanamycin, a heat shock protein 90 inhibitor, resulted in synergistic growth inhibition. Since MS-275 has no reported activity against HDAC6, which regulates both microtubule and heat shock protein 90 functions, other mechanisms of synergy are anticipated.. These results support the role of ZEB proteins and HDAC inhibitors in the pathogenesis and treatment of lung cancer.

Topics: Animals; Antineoplastic Agents; Apoptosis; Benzamides; Benzoquinones; Blotting, Western; Cadherins; Carcinoma, Non-Small-Cell Lung; Cell Proliferation; Female; Flow Cytometry; Histone Deacetylase Inhibitors; Histone Deacetylases; Homeodomain Proteins; HSP90 Heat-Shock Proteins; Humans; Hydroxamic Acids; Lactams, Macrocyclic; Lung Neoplasms; Pyridines; Rats; Rats, Nude; Repressor Proteins; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; RNA, Small Interfering; Transcription Factors; Tumor Cells, Cultured; Up-Regulation; Vorinostat; Zinc Finger E-box Binding Homeobox 2; Zinc Finger E-box-Binding Homeobox 1

To ascertain the potential for histone deacetylase (HDAC) inhibitor-based treatment in non-small cell lung cancer (NSCLC), we analyzed the antitumor effects of trichostatin A (TSA) and suberoylanilide hydroxamic acid (vorinostat) in a panel of 16 NSCLC cell lines via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. TSA and vorinostat both displayed strong antitumor activities in 50% of NSCLC cell lines, suggesting the need for the use of predictive markers to select patients receiving this treatment. There was a strong correlation between the responsiveness to TSA and vorinostat (P < 0.0001). To identify a molecular model of sensitivity to HDAC inhibitor treatment in NSCLC, we conducted a gene expression profiling study using cDNA arrays on the same set of cell lines and related the cytotoxic activity of TSA to corresponding gene expression pattern using a modified National Cancer Institute program. In addition, pathway analysis was done with Pathway Architect software. We used nine genes, which were identified by gene-drug sensitivity correlation and pathway analysis, to build a support vector machine algorithm model by which sensitive cell lines were distinguished from resistant cell lines. The prediction performance of the support vector machine model was validated by an additional nine cell lines, resulting in a prediction value of 100% with respect to determining response to TSA and vorinostat. Our results suggested that (a) HDAC inhibitors may be promising anticancer drugs to NSCLC and (b) the nine-gene classifier is useful in predicting drug sensitivity to HDAC inhibitors and may contribute to achieving individualized therapy for NSCLC patients.

Topics: Algorithms; Antineoplastic Agents; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Cell Proliferation; Drug Screening Assays, Antitumor; Enzyme Inhibitors; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Genes, Neoplasm; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Inhibitory Concentration 50; Lung Neoplasms; Models, Biological; Reproducibility of Results

Analysis of biopsies from a recent clinical trial suggested that Depsipeptide FK228 (DP) inhibits Aurora kinase expression in lung cancer cells. The present study was undertaken to confirm and extend these observations.. Aurora A and B mRNA levels in lung cancer cells were considerably higher than levels in normal pulmonary epithelia. DP, TSA and SAHA inhibited Aurora A, Aurora B and survivin expression with kinetics that were remarkably similar within individual cell lines, and appeared to coincide with p53 expression status. These effects were not observed following treatment with geldanamycins. Inhibition of Aurora B transcription coincided with decreased H3K9Ac and H3K4Me2 activation marks, and accumulation of H3K9Me3, as well as MBD1, MBD2 and MBD3 repression marks within the minimal Aurora B promoter. Knockdown of MBD1, -2 or -3 did not reproducibly abrogate inhibition of Aurora or survivin expression by DP or TSA. DP and TSA decreased expression and altered localization of Aurora kinases and survivin, resulting in mitotic catastrophe in lung cancer cells.. Aurora A, and Aurora B levels in lung cancer cells and normal respiratory epithelia were assessed using quantitative RT-PCR techniques. These methods, as well as as Western blots were used to examine expression of Auroras A/B, and several related genes/proteins in lung cancer cells exposed to DP, TSA, SAHA and geldanamycins. Transient transfection promoter-reporter assays, and chromatin immunoprecipitation (ChIP) techniques were used to examine DP-mediated changes in activity and chromatin structure of the Aurora B promoter. Confocal imaging techniques were used to examine the effects of DP and TSA on mitotic progression in lung cancer cells.. Novel transcriptional regulatory mechanisms involving Aurora kinase and survivin appear to contribute to cytotoxicity mediated by HDAC inhibitors in lung cancer cells.

Topics: Aurora Kinase B; Aurora Kinases; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Clinical Trials, Phase II as Topic; Depsipeptides; Drug Delivery Systems; Enzyme Inhibitors; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Immunohistochemistry; Inhibitor of Apoptosis Proteins; Kinetics; Lung Neoplasms; Microtubule-Associated Proteins; Neoplasm Proteins; Protein Serine-Threonine Kinases; RNA, Messenger; Survivin; Transcription, Genetic; Vorinostat

The importance of alpha-2-glycoprotein 1, zinc (AZGP1) in lung adenocarcinoma (AD) remains largely unknown. Analysis of serum autoantibodies to tumor antigens combined with gene expression profiling of primary tumors may provide insight into the mechanisms underlying lung carcinogenesis and identify new AD biomarkers.. T7 phage cDNA libraries were used to identify AZGP1 autoantibodies in the serum of 473 patients (192 ADs, 192 matched controls, and 89 additional ADs for confirmation of findings). AZGP1 mRNA expression was examined in 86 ADs and 10 control lung tissue samples using oligonucleotide microarrays. AZGP1 protein expression was studied in 230 tissue samples (222 ADs; 8 controls) with immunohistochemistry. Kaplan-Meier analyses were used to correlate circulating autoantibody and tissue mRNA production with survival. AD cell lines A549 and SKLU1 were treated with 5-aza-2;-deoxycytidine (5-AZA) and trichostatin A (TSA) to examine the role of promoter methylation and histone deacetylation in the expression of AZGP1. Real-time polymerase chain reaction was used to quantify the effects of treatment.. In patients with AD, AZGP1 autoantibodies were observed in 40% of serum samples. Autoantibody production correlated with improved overall 5-year survival (p = 0.002) and improved survival in those with stage I to II disease (p = 0.008). A verification analysis was performed for the survival benefit and found similar results with p values of 0.02 and 0.036, respectively. Although abundant mRNA expression was found in a subset of tumors, mRNA expression did not correlate with prognosis. In normal lung, AZGP1 mRNA and protein expression were low or absent, whereas in AD they were highly expressed in 31.3% and 42.8% of samples, respectively. To determine whether AZGP1 expression in this subset of tumors might be affected by epigenetic mechanisms, low AZGP1-expressing A549 and SKLU1 AD cell lines were treated with TSA and 5-AZA. A 713-fold and 169-fold increase in mRNA expression were noted on treatment with TSA, respectively. Treatment with 5-AZA had minimal effect on AZGP1 mRNA expression.. The presence of AZGP1 serum autoantibody may be used as a prognostic marker in patients with AD. Furthermore, up-regulation of AZGP1 mRNA in AD may be affected by chromatin remodeling by means of histone acetylation.

Topics: Acetylation; Adenocarcinoma; Adipokines; Adult; Aged; Aged, 80 and over; Autoantibodies; Azacitidine; Biomarkers, Tumor; Carrier Proteins; Case-Control Studies; Enzyme Inhibitors; Female; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Glycoproteins; Histone Acetyltransferases; Histone Deacetylase Inhibitors; Histone Deacetylases; Humans; Hydroxamic Acids; Immunoenzyme Techniques; Lung Neoplasms; Male; Middle Aged; Oligonucleotide Array Sequence Analysis; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Survival Rate; Tumor Cells, Cultured

The insulin-receptor substrate family plays important roles in cellular growth, signaling, and survival. Two new members of this family have recently been isolated: IRS5/Dok4 and IRS6/Dok5. This study examines the expression of IRS5/DOK4 in a panel of lung cancer cell lines and tumor specimens. The results demonstrate that expression of IRS5/DOK4 is frequently altered with both elevated and decreased expression in non-small-cell lung cancer (NSCLC) tumor specimens. The altered expression of IRS5/DOK4 observed in tumor samples is not due to aberrant methylation. In vitro cell culture studies demonstrate that treatment of NSCLC cell lines with the histone deacetylase inhibitor trichostatin A (TSA) upregulates IRS5/DOK4. This finding indicates that expression is regulated epigenetically at the level of chromatin remodeling. Chromatin immunoprecipitation experiments confirm that the IRS5/DOK4 promoter has enhanced histone hyperacetylation following treatments with TSA. Finally, hypoxia was demonstrated to downregulate IRS5/DOK4 expression. This expression was restored by TSA. The clinical relevance of altered IRS5/DOK4 expression in NSCLC requires further evaluation.

Topics: Acetylation; Adaptor Proteins, Signal Transducing; Adenocarcinoma; Base Sequence; Bronchi; Carcinoma, Non-Small-Cell Lung; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Proliferation; Chromatin Assembly and Disassembly; Chromatin Immunoprecipitation; DNA Methylation; Enzyme Inhibitors; Gene Expression Regulation, Neoplastic; Histone Deacetylase Inhibitors; Histone Deacetylases; Histones; Humans; Hydroxamic Acids; Intracellular Signaling Peptides and Proteins; Lung; Lung Neoplasms; Molecular Sequence Data; Promoter Regions, Genetic; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Transcription, Genetic

Commonly used regimens in cancer therapy rely on the induction of apoptotic cell death, and drug resistance can be attributed, at least in part, to a disabled apoptotic program. Non-small cell lung carcinomas (NSCLC), exhibit an intrinsic resistance to chemotherapy. Here, we show that co-treatment with etoposide (VP16) and the pan-histone deacetylase (HDAC) inhibitor trichostatin A (TSA), but not valproic acid (VPA), induced apoptotic cell death in drug-resistant NSCLC cells. Co-treatment, but not single treatment, with VP16 and TSA induced apoptosis in a caspase-dependent manner accompanied by a crucial decrease in Bcl-xL expression allowing Bax activation and subsequent initiation of the apoptosis inducing factor (AIF)-dependent death pathway. Importantly, AIF proved to be required for the effects of TSA/VP16 as RNA knockdown of AIF resulted in a complete abolishment of TSA/VP16-induced apoptotic cell death in drug-resistant NSCLC cells. Our results thus provide evidence for the requirement of both caspase-dependent and caspase-independent apoptotic pathways in TSA/VP16-mediated death of drug-resistant NSCLC cells, and extend previous suggestions that HDAC inhibitors in combination with conventional chemotherapeutic drugs could be valuable in the treatment of NSCLC cancer and other malignancies in which Bcl-xL is overexpressed.

Topics: Amino Acid Chloromethyl Ketones; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Apoptosis Inducing Factor; bcl-2-Associated X Protein; bcl-X Protein; Carcinoma, Non-Small-Cell Lung; Caspase Inhibitors; Caspases; Drug Evaluation, Preclinical; Etoposide; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung Neoplasms; Models, Biological; RNA, Small Interfering; Signal Transduction; Tumor Cells, Cultured

Humans are exposed to arsenicals through many routes with the most common being in drinking water. Exposure to arsenic has been associated with an increase in the incidence of cancer of the skin, lung and bladder. Although the relationship between exposure and carcinogenesis is well documented, the mechanisms by which arsenic participates in tumorigenesis are not fully elucidated. We evaluated the potential epigenetic component of arsenical action by assessing the histone acetylation state of 13 000 human gene promoters in a cell line model of arsenical-mediated malignant transformation. We show changes in histone H3 acetylation occur during arsenical-induced malignant transformation that are linked to the expression state of the associated gene. DNA hypermethylation was detected in hypoacetylated promoters in the select cases analyzed. These epigenetic changes occurred frequently in the same promoters whether the selection was performed with arsenite [As(III)] or with monomethylarsonous acid, suggesting that these promoters were targeted in a non-random fashion, and probably occur in regions important in arsenical-induced malignant transformation. Taken together, these data suggest that arsenicals may participate in tumorigenesis by altering the epigenetic terrain of select genes.

Topics: Acetylation; Arsenicals; Azacitidine; Cell Line; Cell Line, Tumor; Cell Transformation, Neoplastic; Decitabine; Environmental Exposure; Histones; Humans; Hydroxamic Acids; Lung Neoplasms; Oligonucleotide Array Sequence Analysis; Promoter Regions, Genetic; Reverse Transcriptase Polymerase Chain Reaction; Skin Neoplasms; Teratogens; Urinary Bladder Neoplasms; Urothelium

Epigenetic changes involved in cancer development, unlike genetic changes, are reversible. DNA methyltransferase and histone deacetylase inhibitors show antiproliferative effects in vitro, through tumor suppressor reactivation and induction of apoptosis. Such inhibitors have shown activity in the treatment of hematologic disorders but there is little data concerning their effectiveness in treatment of solid tumors. FHIT, WWOX and other tumor suppressor genes are frequently epigenetically inactivated in lung cancers. Lung cancer cell clones carrying conditional FHIT or WWOX transgenes showed significant suppression of xenograft tumor growth after induction of expression of the FHIT or WWOX transgene, suggesting that treatments to restore endogenous Fhit and Wwox expression in lung cancers would result in decreased tumorigenicity. H1299 lung cancer cells, lacking Fhit, Wwox, p16(INK4a) and Rassf1a expression due to epigenetic modifications, were used to assess efficacy of epigenetically targeted protocols in suppressing growth of lung tumors, by injection of 5-aza-2-deoxycytidine (AZA) and trichostatin A (TSA) in nude mice with established H1299 tumors. High doses of intraperitoneal AZA/TSA suppressed growth of small tumors but did not affect large tumors (200 mm(3)); lower AZA doses, administered intraperitoneally or intratumorally, suppressed growth of small tumors without apparent toxicity. Responding tumors showed restoration of Fhit, Wwox, p16(INKa), Rassf1a expression, low mitotic activity, high apoptotic fraction and activation of caspase 3. These preclinical studies show the therapeutic potential of restoration of tumor suppressor expression through epigenetic modulation and the promise of re-expressed tumor suppressors as markers and effectors of the responses.

Topics: Acid Anhydride Hydrolases; Animals; Apoptosis; Azacitidine; Carcinoma, Non-Small-Cell Lung; Caspases; Cyclin-Dependent Kinase Inhibitor p16; Decitabine; DNA Methylation; DNA Modification Methylases; Enzyme Inhibitors; Epigenesis, Genetic; Female; Gene Expression Regulation, Neoplastic; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung Neoplasms; Mice; Mice, Nude; Neoplasm Proteins; Oxidoreductases; Promoter Regions, Genetic; Transgenes; Transplantation, Heterologous; Tumor Cells, Cultured; Tumor Suppressor Proteins; WW Domain-Containing Oxidoreductase

Lung cancer is the leading cause of cancer-related deaths in the United States due, in large part, to the lack of early detection methods. Lung cancer arises from a complex series of genetic and epigenetic changes leading to uncontrolled cell growth and metastasis. Unlike genetic changes, epigenetic changes, such as DNA methylation and histone acetylation, are reversible with currently available pharmaceuticals and are early events in lung tumorigenesis detectable by non-invasive methods. In order to better understand how epigenetic changes contribute to lung cancer, and to identify new disease biomarkers, we combined pharmacologic inhibition of DNA methylation and histone deacetylation in non-small cell lung cancer (NSCLC) cell lines, with genome-wide expression profiling. Of the more than 200 genes upregulated by these treatments, three of these, neuronatin, metallothionein 3 and cystatin E/M, were frequently hypermethylated and transcriptionally downregulated in NSCLC cell lines and tumors. Interestingly, four other genes, cylindromatosis, CD9, activating transcription factor 3 and oxytocin receptor, were dominantly regulated by histone deacetylation and were also frequently downregulated in lung tumors. The majority of these genes also suppressed NSCLC growth in culture when ectopically expressed. This study therefore reveals new putative NSCLC growth regulatory genes and epigenetic disease biomarkers that may enhance early detection strategies and serve as therapeutic targets.

Topics: Acetylation; Adenocarcinoma; Azacitidine; Biomarkers, Tumor; Carcinoma, Large Cell; Carcinoma, Non-Small-Cell Lung; Carcinoma, Squamous Cell; Chromatin Immunoprecipitation; Colony-Forming Units Assay; DNA Methylation; Enzyme Inhibitors; Epigenesis, Genetic; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung Neoplasms; Oligonucleotide Array Sequence Analysis; Reverse Transcriptase Polymerase Chain Reaction; Tumor Cells, Cultured

Identification of a homozygous deletion in cancer cells provides strong evidence for the location of a tumor suppressor gene (TSG). We analyzed the 2p24 homozygous deletion of a non-small-cell lung cancer (NSCLC) cell line, NCI-H2882, and found that the deletion size was 3.7 Mbp. Since RhoB, which has been suggested to be a candidate TSG, was located in this region, we analyzed RhoB for alterations in NSCLC. Although we found no mutations in 48 cell lines including 20 NSCLCs, a loss of heterozygosity (LOH) analysis in 128 primary NSCLCs showed that 25 of 62 informative samples had LOH at the RhoB locus. Northern blot analysis of 28 cell lines (including 15 NSCLCs) indicated that RhoB expression was downregulated in 27. We analyzed RhoB expression in 112 primary NSCLCs with immunohistochemistry and found no or a weak RhoB expression in 33 (42%) of 78 adenocarcinomas, whereas we found it in 29 (94%) of 31 squamous cell carcinomas. No or a weak expression of RhoB was more frequently observed in poorly- or moderately-differentiated adenocarcinomas than in well-differentiated ones (p = 0.0014). Furthermore, no or a weak expression of RhoB indicated a tendency to poor patient prognosis. Although hypermethylation was not found at the promoter region, the RhoB expression in NSCLC cell lines was induced by histone deacetylase inhibition, suggesting that RhoB downregulation may be due to histone modification. The present study demonstrates that RhoB expression is frequently downregulated in NSCLCs by multiple mechanisms, suggesting that RhoB is a candidate TSG for NSCLC.

Topics: Aged; Blotting, Northern; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Chromosome Deletion; Chromosome Mapping; Chromosomes, Human, Pair 2; DNA Methylation; Down-Regulation; Female; Gene Expression Regulation, Neoplastic; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Immunohistochemistry; Kaplan-Meier Estimate; Loss of Heterozygosity; Lung Neoplasms; Male; Microsatellite Repeats; Middle Aged; Prognosis; Promoter Regions, Genetic; Reverse Transcriptase Polymerase Chain Reaction; rhoB GTP-Binding Protein

The homeobox containing gene HOP (Homeodomain Only Protein) was identified in the developing heart and lung where it functions downstream of Nkx2.5 and Nkx2.1 to modulate cardiac and lung gene expression. Previously, we found that HOP was downregulated in lung cancer. In this study, we constructed an expression vector containing the full-length cDNA of HOP and transfected it into a lung cancer cell line H2170. Stable transfection led to an increased expression of HOP confirmed by Northern blot analysis. HOP positive transfectants remarkably reduced the growth rate and the ability of anchorage-independent growth in soft agar, and moreover suppressed the tumor formation in nude mice compared to controls. Transient transfection of Nkx2.1 into H2170 resulted in the overexpression of HOP, and correspondingly, siRNA silencing of Nkx2.1 reduced the expression of HOP in lung cancer cells. Treatment with a differentiation modulating agent 5-bromodeoxyuridine (BrdU) led to restoration of HOP expression in a small cell lung cancer cell line H526. In 29 paired primary lung tumor samples, loss of heterozygosity (LOH) analysis was performed by using the 3 microsatellite markers D4S189, D4S231 and D4S392 around the region of chromosome 4q12 where HOP locates. LOH was only found in 4 out 23 cases (17.4%) indicating that allelic loss is a rare genetic event not responsible for the downregulation of HOP in lung cancer. Taken together, our data suggest that HOP is a potential tumor suppressor possibly involved in lung cancer differentiation, and functions downstream of Nkx2.1.

Topics: Base Sequence; Blotting, Northern; Blotting, Western; Bromodeoxyuridine; Cell Adhesion; Cell Differentiation; Cell Division; DNA Primers; Gene Silencing; Genes, Homeobox; Homeodomain Proteins; Humans; Hydroxamic Acids; Loss of Heterozygosity; Lung Neoplasms; RNA, Small Interfering

An estimated 162,460 people will die of lung cancer in the United States in 2006, making it the leading cause of cancer deaths. Small cell lung cancer (SCLC) accounts for 20% of all lung cancers and exhibits aggressive behavior with early metastases. Current treatments yield five-year survival rates of 5 to 10%, indicating a need for novel therapeutic approaches. Histone deacetylase inhibitors (HDACIs) represent a new class of anticancer agents. Trichostatin A (TSA), an HDACI, has been shown to inhibit growth in several cancers. We hypothesized that TSA may inhibit proliferation of SCLC cells.. Human SCLC DMS53 cells were treated with TSA (0 to 400 nM). Light microscopy was used to assess changes in cell morphology. Western analysis was performed for acetylated histone 4 to confirm HDAC inhibition. The effect of TSA treatment on cellular growth was measured by the MTT assay. Finally, levels of BCL-2, cleaved poly(ADP-ribose) polymerase, p21, and p27 proteins were measured to look for induction of cell cycle arrest and/or apoptosis.. DMS53 cells treated with TSA underwent dramatic changes in cell appearance. Treated cells assumed round and spindle shapes with distinct cellular borders. Western analysis demonstrated increased levels of acetylated histone 4. TSA treatment resulted in a dose-dependent inhibition of growth. Lastly, elevated p21, p27, and cleaved poly(ADP-ribose) polymerase along with decreased BCL-2 protein levels were observed.. TSA causes morphological differentiation and dose-dependent inhibition of cell growth via cell cycle arrest and subsequent apoptosis. This suggests that TSA and other HDACIs may represent a new potential therapy for patients with SCLC.

Topics: Apoptosis; Carcinoma, Small Cell; Cell Cycle; Cell Division; Cell Line, Tumor; Enzyme Inhibitors; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung Neoplasms

To investigate the influence of trichostatin A (TSA) on the proliferation and phase growth arrest of human lung carcinoma cells and on the expression of histone deacetylase 3 (HDAC3).. Human lung carcinoma cells of the line A549 were cultured and treated with TSA of the concentrations of 5, 10, 20, and 40 microg/L. MTT assay was adopted to observe the proliferation of the cells. The cell cycle was determined by flow cytometry. RT-PCR was used to determine the mRNA expression of P21WAF1/CIP1 gene, a tumor suppressor gene, and histone deacetylase 3 (HDAC3) in the A549 cells.. Trichostatin A treatment led to a time- and dose-dependent inhibition in carcinoma cells A549 proliferation (Twenty-four hours after the treatment of TSA The inhibition rates of the A549 cells in the control group and the cells treated with TSA of the concentrations of 5, 10, 20, and 40 microg/L were 6.2%+/-1.1%, 18.5%+/-2.3%, 28.9%+/-3.6%, 39.4%+/-3.7%, and 45.6%+/-2.7% respectively 24 hours later (P<0.05): 8.1%+/-2.3%, 26.9%+/-4.2%, 35.6%+/-3.8%, 56.5%+/-6.1%, and 69.8%+/-5.3% 48 h later (P<0.05); and 10.5%+/-1.3%, 28.4%+/-3.2%, 50.5%+/-5.8%, 70.5%+/-6.9%, and 78.6%+/-4.5% 72 h later (P<0.05). The percentages of the cells in the G0/G1 phase of the control group and the groups treated by TSA of different concentrations were 56.5%+/-8.1%, 70.5%+/-6.7%, 78.6%+/-4.6%, 82.4%+/-3.7%, and 85.6%+/-7.5% respectively (P<0.05). The mRNA expression of HDAC3 of the control group and the TSA-treated groups were 0.85, 052, 0.43, 0.32, and 0.25 respectively, P<0.05), and the mRNA expression of P21WAF1/CIP1 were 0.09, 0.17, 0.20, 0.27, and 0.35 respectively, P<0.05).. TSA induces the expression of P21WAF1/CIP1 through inhibition of HADC3.

Topics: Cell Cycle; Cell Differentiation; Cell Line, Tumor; Cyclin-Dependent Kinase Inhibitor p21; Dose-Response Relationship, Drug; Enzyme Inhibitors; Gene Expression Regulation, Neoplastic; Histone Deacetylase Inhibitors; Histone Deacetylases; Humans; Hydroxamic Acids; Lung Neoplasms; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger

Tumour drug-resistant ABCB1 gene expression is regulated at the chromatin level through epigenetic mechanisms. We examined the effects of the histone deacetylase inhibitor trichostatin A (TSA) on ABCB1 gene expression in small cell lung carcinoma (SCLC) drug-sensitive (H69WT) or etoposide-resistant (H69VP) cells. We found that TSA induced an increase in ABCB1 expression in drug-sensitive cells, but strongly decreased it in drug-resistant cells. These up- and downregulations occurred at the transcriptional level. Protein synthesis inhibition reduced these modulations, but did not completely suppress them. Differential temporal patterns of histone acetylation were observed at the ABCB1 promoter: increase in H4 acetylation in both cell lines, but different H3 acetylation with a progressive increase in H69WT cells but a transient one in H69VP cells. ABCB1 regulations were not related with the methylation status of the promoter -50GC, -110GC, and Inr sites, and did not result in further changes to these methylation profiles. Trichostatin A treatment did not modify MBD1 binding to the ABCB1 promoter and similarly increased PCAF binding in both H69 cell lines. Our results suggest that in H69 drug-resistant SCLC cell line TSA induces downregulation of ABCB1 expression through a transcriptional mechanism, independently of promoter methylation, and MBD1 or PCAF recruitment.

Topics: ATP Binding Cassette Transporter, Subfamily B; ATP Binding Cassette Transporter, Subfamily B, Member 1; Butyrates; Carcinoma, Small Cell; Cell Cycle Proteins; Cell Line, Tumor; DNA Methylation; Down-Regulation; Drug Resistance, Neoplasm; Gene Expression Regulation, Neoplastic; Histone Acetyltransferases; Histone Deacetylase Inhibitors; Histones; Humans; Hydroxamic Acids; Lung Neoplasms; Models, Biological; p300-CBP Transcription Factors; Promoter Regions, Genetic; Response Elements; Transcription Factors; Transcription, Genetic

To understand the mechanisms of PTEN inactivation, which is reported to be involved in tumor progression and drug resistance in lung cancer, we analyzed the expression levels of PTEN at mRNA and protein levels, along with the genetic and epigenetic status of the PTEN gene, in a panel of lung cancer cell lines. Western blot analysis showed that six out of 25 (24%) cell lines displayed low expression of PTEN protein. The level of PTEN mRNA correlated well with corresponding protein expression in each of these six cell lines. In two of the six cell lines genomic analysis revealed homozygous deletions of the PTEN gene. Another two of the six cell lines displayed hypermethylation of the PTEN gene promoter assessed by methylation-specific PCR. The levels of PTEN mRNA and protein expression in PC9/f9 and PC9/f14 cells, which are gefitinib-resistant derivatives of the gefitinib-sensitive cell line, PC9, were reduced compared to the parental line. After treatment with the demethylating agent 5-aza-2'deoxycytidine (5-AZA) and the histone deacetyltransferase (HDAC) inhibitor Trichostatin A (TSA), the expression levels of PTEN mRNA and protein in these four cell lines (PC9/f9, PC9/f14, PC10 and PC14) were actually restored. In summary, reduction in PTEN protein expression was regulated by histone deacetylation and hypermethylation of the gene promoter, as well as homozygous deletion. In addition, we demonstrated that the combination treatment of gefitinib and TSA induced significant growth inhibition in gefitinib-resistant PC9/f9 and PC9/f14 cells. These findings suggest that the combination of the epidermal growth factor receptor tyrosine kinase inhibitor gefitinib with the demethylating agent 5-AZA and the HDAC inhibitor TSA may be a useful strategy for the treatment of some lung cancers.

Topics: Cell Line, Tumor; DNA Methylation; ErbB Receptors; Gefitinib; Humans; Hydroxamic Acids; Lung Neoplasms; Polymerase Chain Reaction; Protein Kinase Inhibitors; PTEN Phosphohydrolase; Quinazolines; Sequence Analysis, DNA

A homozygous deletion of the DOCK8 (dedicator of cytokinesis 8) locus at chromosome 9p24 was found in a lung cancer cell line by array-CGH analysis. Cloning of the full-length DOCK8 cDNA led us to define that the DOCK8 gene encodes a protein consisting of 2,099 amino acids. DOCK8 was expressed in a variety of human organs, including the lungs, and was also expressed in type II alveolar, bronchiolar epithelial and bronchial epithelial cells, which are considered as being progenitors for lung cancer cells. DOCK8 expression was reduced in 62/71 (87%) primary lung cancers compared with normal lung tissue, and the reduction occurred irrespective of the histological type of lung cancer. 5-Aza-2'-deoxy-cytidine and/or Trichostatin A treatments induced DOCK8 expression in lung cancer cell lines with reduced DOCK8 expression. Therefore, epigenetic mechanisms, including DNA methylation and histone deacetylation, were indicated to be involved in DOCK8 down-regulation in lung cancer cells. Further screening revealed homozygous deletions of the DOCK8 gene in a gastric and a breast cancer cell line. DOCK family proteins have been shown to play roles in regulation of migration, morphology, adhesion and growth of cells. Thus, the present results suggest that genetic and epigenetic inactivation of DOCK8 is involved in the development and/or progression of lung and other cancers by disturbing such regulations.

Topics: Azacitidine; Base Sequence; Cell Line, Tumor; Cloning, Molecular; Decitabine; DNA Methylation; DNA Modification Methylases; Down-Regulation; Epithelial Cells; Gene Deletion; Gene Expression Regulation, Neoplastic; Guanine Nucleotide Exchange Factors; Histone Deacetylase Inhibitors; Homozygote; Humans; Hydroxamic Acids; Lung Neoplasms; Molecular Sequence Data; Transfection

A well-known histone deacetylase inhibitor, trichostatin A, was applied to non-small-cell lung cancer cells to determine whether inhibition of histone deacetylase leads to the production of proteins that either arrest tumor cell growth or lead to tumor cell death.. Trichostatin A (0.01 to 1.0 micromol/L) was applied to one normal lung fibroblast and four non-small-cell lung cancer lines, and its effect was determined by flow cytometry, annexin-V staining, immunoprecipitation, and Western blot analysis.. Trichostatin A demonstrated tenfold greater growth inhibition in all four non-small-cell lung cancer lines compared with normal controls, with a concentration producing 50% inhibition ranging from 0.01 to 0.04 micromol/L for the tumor cell lines and 0.7 micromol/L for the normal lung fibroblast line. Trichostatin A treatment reduced the percentage of cells in S phase (10% to 23%) and increased G1 populations (10% to 40%) as determined by flow cytometry. Both annexin-V binding assay and upregulation of the protein, gelsolin (threefold to tenfold), demonstrated that the tumor cells were apoptotic, whereas normal cells were predominantly in cell cycle arrest. Trichostatin A increased histone H4 acetylation and expression of p21 twofold to 15-fold without significant effect on p16, p27, CDK2, and cyclin D1.. Collectively, these data suggest that inhibition of histone deacetylation may provide a valuable approach for lung cancer treatment. We evaluated trichostatin A as a potential candidate for anticancer therapy in non-small-cell lung cancer.

Topics: Antineoplastic Agents; Apoptosis; Carcinoma, Non-Small-Cell Lung; Cell Cycle; Cell Line; Cell Line, Tumor; Cell Survival; Cyclin D1; Enzyme Inhibitors; Gelsolin; Histone Deacetylase Inhibitors; Histones; Humans; Hydroxamic Acids; Lung; Lung Neoplasms

Topics: Antineoplastic Agents; Carcinoma, Non-Small-Cell Lung; Cell Line; Cell Line, Tumor; Enzyme Inhibitors; Humans; Hydroxamic Acids; Lung; Lung Neoplasms; Protein Synthesis Inhibitors

Loss of tumor suppressor CCAAT/enhancer-binding protein-alpha (C/EBPalpha) expression is seen in several human malignancies, including acute myelogenous leukemia and lung cancer. We hypothesized that DNA methylation and histone acetylation of the C/EBPalpha promoter may modulate C/EBPalpha expression in lung cancer.. We analyzed C/EBPalpha expression in 15 human lung cancer cell lines and in 122 human lung primary tumors by northern blotting, immunoblotting, and immunohistochemistry. C/EBPalpha promoter methylation was assessed using bisulfite sequencing, combined bisulfite restriction analysis, methylation-specific polymerase chain reaction, and Southern blotting. We examined the acetylation status of histones H3 and H4 at the C/EBPalpha promoter by chromatin immunoprecipitation. Binding of methyl-CpG-binding proteins MeCP2 and MBD2 and upstream stimulatory factor (USF) to the C/EBPalpha promoter was assayed in cell lines that were untreated or treated with histone deacetylase inhibitor trichostatin A and demethylating agent 5-aza-2'-deoxycytidine (5-aza-dC) by chromatin immunoprecipitation and by electrophoretic mobility shift assays.. DNA methylation and histone acetylation in the upstream region (-1422 to -896) of the C/EBPalpha promoter were associated with low or absent C/EBPalpha expression in 12 of 15 lung cancer cell lines and in 81 of 120 primary lung tumors. MeCP2 and MBD binding to the upstream C/EBPalpha promoter was detected in C/EBPalpha-nonexpressing cell lines; USF binding was detected in C/EBPalpha-expressing cell lines; however, in C/EBPalpha-nonexpressing cell lines USF binding was detected only after trichostatin A and 5-aza-dC treatment.. DNA hypermethylation of the upstream C/EBPalpha promoter region, not the core promoter region as previously reported, is critical in the regulation of C/EBPalpha expression in human lung cancer.

Topics: Acetylation; Azacitidine; Blotting, Northern; Blotting, Southern; Carcinoma, Non-Small-Cell Lung; CCAAT-Enhancer-Binding Protein-alpha; Cell Line, Tumor; Chromatin Immunoprecipitation; CpG Islands; DNA Methylation; DNA-Binding Proteins; Electrophoretic Mobility Shift Assay; Enzyme Inhibitors; Epigenesis, Genetic; Gene Expression Regulation, Neoplastic; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Immunoblotting; Immunohistochemistry; Lung Neoplasms; Methyl-CpG-Binding Protein 2; Mutagenesis; Promoter Regions, Genetic; Sequence Analysis, DNA; Upstream Stimulatory Factors

Recently, the inhibition of histone deacetylase (HDAC) enzymes has attracted attention in the oncologic community as a new therapeutic opportunity for hematologic and solid tumors including non-small cell lung cancer (NSCLC). In hematologic malignancies, such as diffuse large B-cell lymphoma, the HDAC inhibitor (HDI), suberoylanilide hydroxamic acid (SAHA), has recently entered phase II and III clinical trials. To further advance our understanding of their action on tumor cells, we investigated the possible effect of HDI treatment on the functionality of the nuclear factor-kappaB (NF-kappaB) pathway in NSCLC. We found that in the NSCLC cell lines, A549 and NCI-H460, the NF-kappaB pathway was strongly inducible, for example, by stimulation with tumor necrosis factor-alpha (TNF-alpha). Incubation of several NSCLC cell lines with HDIs resulted in greatly reduced gene expression of TNF-alpha receptor-1. HDI-treated A549 and NCI-H460 cells down-regulated TNF-alpha receptor-1 mRNA and protein levels as well as surface exposure, and consequently responded to TNF-alpha treatment with reduced IKK phosphorylation and activation, delayed IkappaB-alpha phosphorylation, and attenuated NF-kappaB nuclear translocation and DNA binding. Accordingly, stimulation of NF-kappaB target gene expression by TNF-alpha was strongly decreased. In addition, we observed that SAHA displayed antitumor efficacy in vivo against A549 xenografts grown on nude mice. HDIs, therefore, might beneficially contribute to tumor treatment, possibly by reducing the responsiveness of tumor cells to the TNF-alpha-mediated activation of the NF-kappaB pathway. These findings also hint at a possible use of HDIs in inflammatory diseases, which are associated with the overproduction of TNF-alpha, such as rheumatoid arthritis or Crohn's disease.

Topics: Animals; Antineoplastic Agents; Carcinoma, Non-Small-Cell Lung; Cell Growth Processes; Cell Line, Tumor; DNA, Neoplasm; Down-Regulation; Enzyme Inhibitors; Female; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; I-kappa B Kinase; Lung Neoplasms; Mice; Mice, Nude; NF-kappa B; Phosphorylation; Receptors, Tumor Necrosis Factor, Type I; Tumor Necrosis Factor-alpha; Vorinostat; Xenograft Model Antitumor Assays

Trichostatin A (TSA), originally developed as an antifungal agent, is one of potent histone deacetylase (HDAC) inhibitors, which are known to cause growth arrest and apoptosis induction of transformed cells, including urinary bladder, breast, prostate, ovary, and colon cancers. However, the effect of HDAC inhibitors on human non-small cell lung cancer cells is not clearly known yet. Herein, we demonstrated that treatment of TSA resulted in a significant decrease of the viability of H157 cells in a dose-dependent manner, which was revealed as apoptosis accompanying with nuclear fragmentation and an increase in sub-G0/G1 fraction. In addition, it induced the expression of Fas/FasL, which further triggered the activation of caspase-8. Catalytic activation of caspase-9 and decreased expression of anti-apoptotic Bcl-2 and Bcl-XL proteins were observed in TSA-treated cells. Catalytic activation of caspase-3 by TSA was further confirmed by cleavage of pro-caspase-3 and intracellular substrates, including poly (ADP-ribose) polymerase (PARP) and inhibitor of caspase-activated deoxyribonuclease (ICAD). In addition, a characteristic phenomenon of mitochondrial dysfunction, including mitochondrial membrane potential transition and release of mitochondrial cytochrome c into the cytosol was apparent in TSA-treated cells. Taken together, our data indicate that inhibition of HDAC by TSA induces the apoptosis of H157 cells through signaling cascade of Fas/FasL-mediated extrinsic and mitochondria-mediated intrinsic caspases pathway.

Topics: Acetylation; Apoptosis; Caspase 3; Caspase 8; Caspase 9; Catalysis; Cell Line, Tumor; Enzyme Activation; Histones; Humans; Hydroxamic Acids; Lung Neoplasms; Mitochondria; Protein Isoforms; Receptors, Death Domain; Signal Transduction

Histone deacetylase inhibitors mediate a potent growth-inhibitory effect in cancer cells through induction of cell-cycle arrest and apoptosis. Moreover, these agents significantly induce transcriptional activation of nuclear factor kappaB, as well as p21 regulated by protein kinase C, and are thought to negatively influence the ability of histone deacetylase inhibitor to effectively mediate apoptosis. This study aimed to evaluate the effect of calphostin C (a protein kinase C inhibitor) on trichostatin A (a histone deacetylase inhibitor)-mediated upregulation of nuclear factor kappaB and p21 promotor transcriptional activity, as well as induction of apoptosis in lung and esophageal cancer cells.. Cultured lung and esophageal cancer cells were treated with calphostin C and trichostatin A. Nuclear factor kappaB transcriptional activity was quantitated by using the nuclear factor kappaB-luciferase assay. Transcription of p21 gene and p21 protein levels was evaluated by using the p21 promoter-luciferase assay and the p21 enzyme-linked immunoassay, respectively. Apoptosis was evaluated by using the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling-based ApoBrdU assay. Levels of expression of nuclear factor kappaB-dependent antiapoptotic and proapoptotic proteins were evaluated by means of Western blotting.. Exposure of lung or esophageal cancer cells to trichostatin A resulted in a dose- and cell-dependent 2-fold to greater than 20-fold increase of nuclear factor kappaB and p21 transcriptional activity. Treatment with trichostatin A and calphostin C led to a 50% to 90% decrease of trichostatin A- mediated upregulation of nuclear factor kappaB and p21 activation. Inhibition of nuclear factor kappaB activity resulted in significant reduction (30% to >99%) of trichostatin A- mediated activation of not only nuclear factor kappaB transcription but also p21 promotor activity. Importantly, 90% to 96% of thoracic cancer cells under-went apoptosis after exposure to the combination of trichostatin A plus calphostin C.. Inhibition of protein kinase C abrogates trichostatin A-mediated upregulation of nuclear factor kappaB transcriptional activity and p21 expression that is associated with profound induction of apoptosis in lung or esophageal cancer cells. Protein kinase C might be a novel target for enhancing the efficacy of histone deacetylase inhibitor in cancer therapy.

Topics: Apoptosis; Blotting, Western; Cell Proliferation; Cell Survival; Drug Therapy, Combination; Esophageal Neoplasms; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung Neoplasms; Naphthalenes; NF-kappa B; Oncogene Protein p21(ras); Probability; Protein Kinase C; Risk Factors; Sensitivity and Specificity; Tumor Cells, Cultured; Up-Regulation

Although histone deacetylase (HDAC) inhibitors are emerging as a promising new treatment strategy in malignancy, how they exert their effect on human non-small cell lung cancer cells is as yet unclear. This study was undertaken to investigate the underlying mechanism of an HDAC inhibitor, Trichostatin A (TSA), -induced apoptosis in a human lung carcinoma cell line A549. The effects of this compound were also tested on cyclooxygenase (COX) activity. Treatment of A549 cells to TSA resulted in the inhibition of viability and the induction of apoptosis in a concentration-dependent manner, which could be proved by trypan blue counts, DAPI staining, agarose gel electrophoresis and flow cytometry analysis. Apoptosis of A549 cells by TSA was associated with a down-regulation of anti-apoptotic Bcl-2 protein and an up-regulation of pro-apoptotic Bax protein. TSA treatment induced the proteolytic activation of caspase-3 and caspase-9, and a concomitant degradation of poly(ADP-ribose)-polymerase protein. Furthermore, TSA decreased the levels of COX-2 mRNA and protein expression without significant changes in the levels of COX-1, which was correlated with an inhibition in prostaglandin E2 synthesis. Taken together, these findings provide important new insights into the possible molecular mechanisms of the anti-cancer activity of TSA.

Topics: Apoptosis; Blotting, Western; Carcinoma, Non-Small-Cell Lung; Caspase 3; Caspase 9; Caspases; Cell Line, Tumor; Cell Survival; Dinoprostone; DNA Fragmentation; Dose-Response Relationship, Drug; Enzyme Inhibitors; Flow Cytometry; Gene Expression Regulation, Enzymologic; Histone Deacetylase Inhibitors; Histone Deacetylases; Humans; Hydroxamic Acids; Lung Neoplasms; Poly(ADP-ribose) Polymerases; Proto-Oncogene Proteins c-bcl-2; Reverse Transcriptase Polymerase Chain Reaction

Runt-related transcription factor 3 (RUNX3) has been recognized as a tumor suppressor gene in gastric cancer because its expression level was reduced or disappeared due to epigenetic changes. To evaluate the usefulness of the RUNX3 gene as a biomarker of lung cancer, we have analyzed the expression of the RUNX3 gene in 15 lung cancer cell lines by real-time reverse transcription-polymerase chain reaction (RT-PCR), and demonstrated that RUNX3 gene expression was reduced or disappeared in all cell lines examined (100%). In addition, we have attempted to classify all the cell lines into three groups according to the expression level; less than 10% (group I), 10-30% (group II) and approximately 50% (group III). We further investigated methylation status of the CpG sites in the exon 1 region of RUNX3 by methylation specific PCR (MSP), and studied the correlation between the expression level and hemizygous deletion as revealed by bicolor fluorescence in situ hybridization (FISH). The CpG sites were hypermethylated in 8 cell lines (53%) and the RUNX3 loci were hemizygously deleted in another 8 cell lines (53%). Furthermore group I, II, and III corresponded well to methylation-positive cell lines, cell lines showing hemizygous deletion, and the rest of cell lines without methylation or hemizygous deletion, respectively. These results suggest that a comprehensive study on RUNX3 using real-time RT-PCR, MSP, and FISH could be beneficial in understanding the pathogenetic mechanisms of human lung cancer at the molecular level.

Topics: Alleles; Antimetabolites, Antineoplastic; Azacitidine; Biomarkers, Tumor; Cell Line, Tumor; Chromosomes, Human, Pair 1; Core Binding Factor Alpha 3 Subunit; CpG Islands; DNA Methylation; DNA, Complementary; Down-Regulation; Exons; Gene Deletion; Gene Expression Regulation, Neoplastic; Humans; Hydroxamic Acids; In Situ Hybridization, Fluorescence; Lung Neoplasms; Polymerase Chain Reaction; Protein Synthesis Inhibitors; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger

We previously reported silencing of the TGF-beta type II receptor gene (TGFbetaRII), involving histone deacetylation, instead of DNA methylation (DNA-Me). Because different histone modifications may play crucial roles in the epigenetic alterations, we further studied links with silencing of the TGFbetaRII gene promoter in six lung cancer cell lines. ChIP assays demonstrated three chromatin patterns for this gene silencing (Pattern I: histone H3 acetylation (H3-Ac)(+/-)/histone H3 lysine 4 methylation (H3K4-Me)(+)/DNA-Me(-), Pattern II; H3-Ac(-)/H3K4-Me(+/-)/DNA-Me(-), and Pattern III; H3-Ac(-)/H3K4-Me(-)/DNA-Me(+)), indicating possible progressive alterations with H3K4-Me alteration. With exposure to a histone deacetylase inhibitor (HDAC-I), trichostatin A, cell lines with the pattern II demonstrated strong and persistent induction of TGFbetaRII expression, while those with the pattern III showed only weak or no induction. ACC-LC-91 cell line, one of the pattern II examples demonstrated strong and continuous induction of H3K4-Me similar to TGFbetaRII expression. In contrast, ACC-LC-176 with the pattern III showed only weak and transient induction of H3K4-Me, similar to TGFbetaRII expression. Treatment with 5-aza-2'-deoxycytidine (5aza-dC) in addition to HDAC-I resulted in strong and continuous induction of TGFbetaRII expression and H3K4-Me in ACC-LC-176, although 5aza-dC alone was without such effects. In ACC-LC-91, both H3-Ac and H3K4-Me were promptly and simultaneously induced by HDAC-I, and similarly inhibited by wortmannin, a PI3K family inhibitor, together with TGFbetaRII induction. These findings suggested progressive alterations of chromatin configuration including H3K4-Me alteration in TGFbetaRII gene silencing. A possible involvement of a wortmannin-sensitive kinase in histone modification was also suggested.

Topics: Acetylation; Androstadienes; Azacitidine; Chromatin; DNA Methylation; Enzyme Inhibitors; Gene Expression Regulation, Neoplastic; Gene Silencing; Histone Deacetylase Inhibitors; Histones; Humans; Hydroxamic Acids; Lung Neoplasms; Lysine; Phosphoinositide-3 Kinase Inhibitors; Promoter Regions, Genetic; Protein Serine-Threonine Kinases; Receptor, Transforming Growth Factor-beta Type II; Receptors, Transforming Growth Factor beta; Signal Transduction; Transcription, Genetic; Tumor Cells, Cultured; Wortmannin

The effects of the histone deacetylase inhibitors (HDACi) trichostatin A (TSA) and sodium butyrate (NaBt) were studied in A549, HT29 and FHC human cell lines. Global histone hyperacetylation, leading to decondensation of interphase chromatin, was characterized by an increase in H3(K9) and H3(K4) dimethylation and H3(K9) acetylation. The levels of all isoforms of heterochromatin protein, HP1, were reduced after HDAC inhibition. The observed changes in the protein levels were accompanied by changes in their interphase patterns. In control cells, H3(K9) acetylation and H3(K4) dimethylation were substantially reduced to a thin layer at the nuclear periphery, whereas TSA and NaBt caused the peripheral regions to become intensely acetylated at H3(K9) and dimethylated at H3(K4). The dispersed pattern of H3(K9) dimethylation was stable even at the nuclear periphery of HDACi-treated cells. After TSA and NaBt treatment, the HP1 proteins were repositioned more internally in the nucleus, being closely associated with interchromatin compartments, while centromeric heterochromatin was relocated closer to the nuclear periphery. These findings strongly suggest dissociation of HP1 proteins from peripherally located centromeres in a hyperacetylated and H3(K4) dimethylated environment. We conclude that inhibition of histone deacetylases caused dynamic reorganization of chromatin in parallel with changes in its epigenetic modifications.

Topics: Apoptosis; Butyric Acid; Carcinoma, Small Cell; Cell Cycle; Cell Line; Cell Line, Tumor; Cell Nucleus; Chromatin; Chromobox Protein Homolog 5; Chromosomal Proteins, Non-Histone; Colonic Neoplasms; Enzyme Inhibitors; Fetus; Histone Deacetylase Inhibitors; Histone Deacetylases; Histones; HT29 Cells; Humans; Hydroxamic Acids; Interphase; Lung Neoplasms

Histone deacetylase inhibitors (HDI) have been reported to inhibit the growth and survival of cancer cells while leaving normal cells untouched. However, the mechanisms underlying this selective cell death are poorly understood. Gene expression analysis revealed that HDI treatment induced up-regulation of p21(WAF1/Cip1) and down-regulation of ErbB2 in cancer cells but not normal cells. Overexpression of p21(WAF1/Cip1) and/or silencing of ErbB2 enhanced cancer cell growth inhibition, suggesting that HDI-induced up-regulation/down-regulation of these genes play critical roles in HDI-induced growth inhibition of cancer cells. Most importantly, we found that the gene silencing factor methyl CpG-binding domain protein 3 (MBD3) was not only released from cancer-selective promoter of the HDI up-regulated p21(WAF1/Cip1) gene but also recruited to that of the HDI-down-regulated ErbB2 gene. Furthermore, silencing of MBD3 by small interfering RNA abrogated the HDI-induced gene regulation and growth inhibition in lung cancer but not in normal cells. Together, our results support the critical potential of MBD3 in HDI-induced cancer-selective cell death via cancer differential gene expression.

Topics: Cyclin-Dependent Kinase Inhibitor p21; DNA-Binding Proteins; Enzyme Inhibitors; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Gene Silencing; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung Neoplasms; Oligonucleotide Array Sequence Analysis; Promoter Regions, Genetic; Protein Kinase C; Receptor, ErbB-2; RNA, Small Interfering; Transcriptional Activation; Tumor Cells, Cultured

Recently, we isolated a candidate tumor-suppressor gene, MYO18B, which was inactivated in approximately 50% of human lung cancers by deletion, mutation, and promoter methylation. However, more frequent reduction or loss of MYO18B expression and restoration of MYO18B expression by trichostatin A (TSA) treatment suggested the contribution of other mechanisms, especially histone deacetylation, for epigenetic inactivation of the MYO18B gene. In this study, we examined histone modification of the promoter region of the MYO18B gene in 8 human lung cancer cell lines by a chromatin immunoprecipitation assay. In 6 of 7 cell lines with reduced or silenced MYO18B expression, the levels of histones H3 and H4 acetylation surrounding the MYO18B promoter region were lower than those in a cell line with MYO18B expression. By treatment with TSA, the levels of histone H3 and H4 acetylation were increased in all 6 cell lines whose MYO18B expression was restored by TSA, whereas neither H3 nor H4 acetylation was increased in cells whose MYO18B expression was not restored by TSA. Significant correlations were observed between the levels of histone H3/H4 acetylation and MYO18B expression. These results suggest that acetylation of both histones H3 and H4 contributes to regulation of MYO18B expression in lung cancer cells and that histone deacetylation surrounding the promoter region plays an important role in MYO18B silencing and is involved in lung carcinogenesis.

Topics: Acetylation; Cell Line, Tumor; DNA Methylation; Gene Expression Regulation, Neoplastic; Histones; Humans; Hydroxamic Acids; Lung Neoplasms; Myosin Heavy Chains; Promoter Regions, Genetic

Topics: Azacitidine; beta Catenin; Carcinoma, Non-Small-Cell Lung; Cell Division; Cell Line, Tumor; Cytoskeletal Proteins; Decitabine; Desmoplakins; DNA Modification Methylases; gamma Catenin; Humans; Hydroxamic Acids; Lung Neoplasms; Neoplasm Proteins; Trans-Activators

Texture analysis of chromatin patterns by image cytometry can be used in the development and refinement of diagnosis and prognosis of cancers and in the follow-up of therapies. However, little is known about the biological mechanisms underlying these patterns. Epigenetic mechanisms as histone posttranslational modifications and particularly histone acetylation could play a major role in the determination of these chromatin patterns and then influence nuclear texture measurements.. This study examined the consequences of treatment by the histone deacetylase inhibitor trichostatin A (TSA) on the nuclear texture in human cell lines sensitive and resistant to chemotherapy. Small cell lung carcinoma H69 cells and their variant H69-VP, which is resistant to etoposide, were incubated with 100 ng/ml of TSA for 0 to 24 h. Nuclear texture was evaluated by image cytometry and compared with the histone H4 acetylation level measured by western blotting and expression of c-jun gene evaluated by reverse transcription and real-time polymerase chain reaction.. TSA treatment induced an increase in histone H4 acetylation level in both cell lines. However, at the level of chromatin texture, sensitive H69 cells displayed a progressive chromatin decondensation up to 24 h, whereas resistant H69-VP showed rapid (8 h) but transient changes. Similarly, expression of c-jun increased regularly in TSA-treated H69 cells. In H69-VP cells, an increase was also observed up to 12 h followed by a decrease after 24 h of treatment.. Analysis of nuclear texture appeared to be a sensitive technique to detect chromatin pattern alterations induced by the histone deacetylase inhibitor TSA in the H69 cell line and enabled the observation of chromatin pattern discrepancies between chemotherapeutic drug-sensitive and drug-resistant cells during this treatment. When c-jun gene expression was analyzed as gene sensitive to epigenetic control, these textural differences seemed to be correlated to gene expression.

Topics: Carcinoma, Small Cell; Cell Line, Tumor; Cell Nucleus; Cell Survival; Chromatin; Drug Resistance, Neoplasm; Enzyme Inhibitors; Epigenesis, Genetic; Gene Expression; Genes, jun; Histone Deacetylases; Humans; Hydroxamic Acids; Image Cytometry; Immunoblotting; Lung Neoplasms; Reverse Transcriptase Polymerase Chain Reaction

Histone deacetylase (HDAC) inhibitors are known to exert antimetastatic and antiangiogenic activity in vitro and in vivo. RECK is a membrane-anchored glycoprotein that negatively regulates matrix metalloproteinases (MMPs) and inhibits tumor metastasis and angiogenesis. In this study, we test the possibility that HDAC inhibitor may increase RECK expression to inhibit MMP activation and cancer cell invasion. Our results showed that trichostatin A (TSA) up-regulated RECK via transcriptional activation in CL-1 human lung cancer cells. Flow cytometric analysis demonstrated that RECK protein on cell surface was increased after treatment of TSA. Moreover, up-regulation of RECK expression by TSA attenuated MMP-2 activity. To explore whether HDAC inhibitor-induced inhibition of MMP-2 activation is indeed mediated via RECK, we used small interference RNA (siRNA) to block RECK expression and found that inhibition of RECK by siRNA abolished the inhibitory effect of TSA on MMP-2 activation. In addition, TSA suppressed the invasive ability of CL-1 cells. Taken together, this study reveals a novel mechanism by which HDAC inhibitors suppress tumor invasion and provides a new strategy for cancer therapy.

Topics: Enzyme Activation; Enzyme Inhibitors; Gene Expression Regulation, Neoplastic; GPI-Linked Proteins; Histone Deacetylase Inhibitors; Histone Deacetylases; Humans; Hydroxamic Acids; Lung Neoplasms; Matrix Metalloproteinase 2; Membrane Glycoproteins; Neoplasm Invasiveness; Neoplasm Metastasis; Neoplasm Proteins; RNA Interference; RNA, Small Interfering; Transcription, Genetic; Tumor Cells, Cultured

Recently, we used gene expression profiling of lung adenocarcinoma and paired normal tissue from smokers and nonsmokers to identify genes and molecular pathways associated with cigarette smoking and lung carcinogenesis. The gene encoding Glypican 3, a glycosylphosphatidylinositol-linked heparan sulfate proteoglycan, was decreased in lung adenocarcinoma. Within nonmalignant lung, GPC3 expression was decreased in smokers compared with nonsmokers; indicating that expression is associated with cigarette smoking. Microarray results were confirmed using an independent cohort of tumors and nonmalignant lung tissues. Immunohistochemical studies localized Glypican 3 protein expression to the apical surface of lung bronchiolar epithelial cells, potential cells of origin for adenocarcinoma. Northern blot analysis demonstrated expression was absent in all tested non-small cell lung carcinoma lines. Pharmacologic treatment of lung cell lines indicated that GPC3 expression was epigenetically silenced by promoter hypermethylation. Human lung carcinoma tumor cells ectopically expressing GPC3 demonstrated increased apoptosis response when exposed to etoposide and growth inhibition when implanted in nude mice. These findings suggest that GPC3 is a candidate lung tumor suppressor gene whose expression may be regulated by exposure to cigarette smoke and functions to modulate cellular response to exogenous damage.

Topics: Adenocarcinoma; Animals; Apoptosis; Azacitidine; Cell Line, Tumor; Decitabine; Enzyme Inhibitors; Gene Expression Profiling; Genes, Tumor Suppressor; Glypicans; Humans; Hydroxamic Acids; Lung Neoplasms; Membrane Proteins; Mice; Neoplasm Proteins; Oligonucleotide Array Sequence Analysis; Respiratory Mucosa; Smoking; Tumor Suppressor Proteins

Histone deacetylase (HDAC) shows a high expression in many cancer cells and the inhibitor of HDAC1, trichostatin A (TSA), can inhibit the growth of cancer cells. Hypoxia is a common feature of malignant tumors. This paper was designed to investigate the expression of HDAC1 of A549 cell strains in hypoxia condition and the effect of TSA on their proliferation and apoptosis.. The authors designed 1 normoxia group (control group) and 5 hypoxia groups (test groups): hypoxia 6h group (A), TSA + hypoxia 6h (B), hypoxia 12h group (C), hypoxia 24h group (D), TSA + hypoxia 24h (E), hypoxia 48h group (F). The expression of HDAC1 in A549 cells was examined using Western blot analysis. Proliferation, the apoptotic rates of A549 cells and the effect of TSA on them were determined using MTT method, immunohistochemistry, TUNEL method, and flow cytometry. The expression of mRNA of HDAC1 and the effect of TSA on it were determined using reverse transcription-polymerase chain reaction (RT-PCR).. The A values expressed by HDAC1 in A549 cell strains were 138+/-11 in the control group, 78+/-4, 86+/-5, 124+/-3, and 120+/-9 in test groups A, C, D, and F, respectively. The A values of HDAC1mRNA versus the A values of beta-Atin mRNA were 0.68+/-0.03 in the control group, 0.46+/-0.03, 0.45+/-0.02, 0.70+/-0.03, and 0.33+/-0.02 in test groups A, C, D, and F, respectively. The A values of the expression of PCNA in A549 cell strains were 0.13+/-0.03 in the control group, 0.10+/-0.02, 0.11+/-0.02, 0.16+/-0.02, and 0.11+/-0.03 in test groups A, B, D, and E, respectively. The A values of MTT in A549 cell strains were 0.50+/-0.06 in the control group, 0.41+/-0.04, 0.45+/-0.03, 0.59+/-0.02, and 0.45+/-0.03 in test groups A, B, D, and E, respectively. The A values of positive cells of apoptosis in A549 cell strains were 0.16+/-0.04 in the control group, 0.18+/-0.02, 0.18+/-0.05, 0.20+/-0.05, and 0.23+/-0.05 in test groups A, B, D, and E, respectively. The apoptotic rates in A549 cells were 1.11% in the control group, 18.91%,14.30%, 36.99%, and 51.92% in test groups A, B, D, and E, respectively.. The expression of HDAC1 plays an important role in the proliferation and apoptosis of A549 cells, which is regulated by hypoxia. TSA may serve as a new target for therapy of lung cancer.

Topics: Apoptosis; Cell Division; Cell Hypoxia; Cell Line, Tumor; Histone Deacetylase 1; Histone Deacetylases; Humans; Hydroxamic Acids; Lung Neoplasms; Proliferating Cell Nuclear Antigen; RNA, Messenger

This paper was designed to investigate the expression of p53, p21 of A549 cell strains under hypoxic condition and the effect of trichostatin A (TSA), the inhibitor of histone deacetylasel (HDAC1) on their expression. The authors designed 1 normoxia group (control group) and 6 hypoxia groups (experimental group): hypoxia 6 h group (A), TSA+hypoxia 6 h (B), hypoxia 12 h group (C), hypoxia 24 h group (D), TSA+hypoxia 24 h (E), hypoxia 48 h group (F). The expression of HDAC1 in A549 cells was examined by using Western blot and the expression of p53, p21 in A549 cells and the effect of TSA on them were determined by using immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR). The A value expressed by HDAC1 in A549 cell strains was 138+/-11 in the control group, 78+/-4, 86+/-5, 124+/-3, 120+/-9 in experimental groups A, C, D, F, respectively. The A value of the expression of the protein and mRNA of p53 in A549 cell strains were 0.12+/-0.02, 0.62+/-0.02 in the control group, 0.10+/-0.03, 0.32 +/-0.03; 0.11+/-0.01, 0.33+/-0.02; 0.13+/-0.03, 0.58+/-0.01; 0.12+/-0.02, 0.56+/-0.02 in experimental group A, B, D, E, respectively. The A value of the expression of the protein and mRNA of p21 in A549 cell strains were 0.17+/-0.03, 0.62+/-0.03 in the control group, 0.16+/-0.02, 0.50+/-0.02; 0.14+/-0.02, 0.36+/-0.02; 0.15+/-0.03, 0.49+/-0.03; 0.13+/-0.02, 0.33+/-0.02 in experimental groups A, B, D, E, respectively. These results indicate that the expression of HDAC1 is regulated by hypoxia and the effect of TSA is closely related to the expression of P21 under hypoxia condition.

Topics: Adenocarcinoma; Cell Hypoxia; Cyclin-Dependent Kinase Inhibitor p21; Cyclins; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung Neoplasms; RNA, Messenger; Tumor Cells, Cultured; Tumor Suppressor Protein p53

The FEZ1/LZTS1 (FEZ1) gene, located on chromosome 8p22 (8p22), was identified recently as a candidate tumor suppressor gene. Because loss of heterozygosity at 8p21-22 is a frequent event in lung cancers, we studied FEZ1 alteration in short-term cultures of resected lung cancer tumors and cell lines.. We examined FEZ1 expression in 17 non-small cell lung cancer (NSCLC), 19 small cell lung cancer (SCLC) cell lines, and 6 pairs of short-term cultures of resected NSCLCs and accompanying nonmalignant bronchial cells (NBECs) by reverse transcription-PCR and Western blotting. To investigate the mechanism for silencing, cells were cultured with 5-aza-2'-deoxycytidine or trichostatin A. We screened for genomic mutations by PCR-single-strand conformational polymorphism.. Thirteen of 17 NSCLC (76%) and 3 of 19 SCLC (16%) of cell lines showed absent expression (P = 0.001). Of the paired NSCLC-NBEC cultures, 3 of 6 showed loss of expression in tumor cell cultures. In the cell lines retaining expression, the amplicon products in SCLCs were more intense than those of NSCLCs and NBECs. Expression of FEZ1 was not restored by 5-aza-2'-deoxycytidine and trichostatin A. Although FEZ1 expression was moderately correlated with loss of heterozygosity of specific microsatellite makers at 8p21-22 in NSCLC cell lines, it was strongly correlated to D8S261 and LPL loci in SCLC cell lines. No mutation was found within cording region of FEZ1 by PCR-single-strand conformational polymorphism.. We found differential FEZ1 expression in NSCLC and SCLC cell lines, and the absent expression in 3 of 6 short-term cultures of NSCLC tumors. FEZ1 may be related to tumorigenesis of lung cancer.

Topics: Adaptor Proteins, Signal Transducing; Adenocarcinoma; Azacitidine; Blotting, Western; Carcinoma, Large Cell; Carcinoma, Squamous Cell; Chromosomes, Human, Pair 8; CpG Islands; Decitabine; DNA Modification Methylases; DNA-Binding Proteins; DNA, Neoplasm; Enzyme Inhibitors; Gene Expression Regulation, Neoplastic; Genes, Tumor Suppressor; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Loss of Heterozygosity; Lung Neoplasms; Nerve Tissue Proteins; Polymorphism, Single-Stranded Conformational; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Tumor Cells, Cultured; Tumor Suppressor Proteins

Histone deacetylase (HDAC) inhibitors and ligands of the peroxisome proliferator-activated receptor gamma (PPARgamma) have been shown previously to induce growth arrest and differentiation in a variety of cancer cell lines. The purpose of this study was to determine whether HDAC inhibitors function similarly in non-small cell lung cancer (NSCLC) and whether combination treatment with HDAC inhibitors and PPARgamma ligands is more efficacious than either agent alone.. Nanomolar concentrations of trichostatin A induced growth arrest in five of seven NSCLC cell lines, whereas sodium phenylbutyrate (PB) was markedly less potent. In adenocarcinomas, trichostatin A up-regulated general differentiation markers (gelsolin, Mad, and p21/WAF1) and down-regulated markers of the type II pneumocyte progenitor cell lineage (MUC1 and SP-A), indicative of a more mature phenotype. PB had a similar effect. Simultaneous treatment with a PPARgamma ligand and PB enhanced the growth inhibition in adenocarcinomas but not in nonadenocarcinomas. Growth arrest was accompanied by markedly decreased cyclin D1 expression but not enhanced differentiation.. The present study demonstrates potent growth-inhibitory and differentiation-inducing activity of HDAC inhibitors in NSCLC and suggests that combination differentiation therapy should be explored further for the treatment of lung adenocarcinomas.

Topics: Adenocarcinoma; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; Blotting, Western; Carcinoma, Non-Small-Cell Lung; Cell Differentiation; Cell Division; Cyclin-Dependent Kinase Inhibitor p21; Cyclins; DNA-Binding Proteins; Dose-Response Relationship, Drug; Drug Synergism; Gelsolin; Gene Expression Regulation, Neoplastic; Histone Deacetylase Inhibitors; Histone Deacetylases; Humans; Hydroxamic Acids; Ligands; Lung Neoplasms; Phenylbutyrates; Receptors, Cytoplasmic and Nuclear; Repressor Proteins; RNA; Thiazoles; Thiazolidinediones; Transcription Factors; Tumor Cells, Cultured

Ectopic secretion of ACTH, from sites such as small cell lung cancer (SCLC), results in severe Cushing's syndrome. ACTH is cleaved from POMC. The syndrome may occur when the highly tissue-specific promoter of the human POMC gene (POMC) is activated. The mechanism of activation is not fully understood. This promoter is embedded within a defined CpG island, and CpG islands are usually considered to be unmethylated in all tissues. We demonstrate that much of this CpG island is methylated in normal nonexpressing tissues, in contrast to somatically expressed CpG island promoters reported to date, and is specifically unmethylated in expressing tissues, tumors, and the POMC-expressing DMS-79 SCLC cell line. A narrow 100-bp region is free of methylation in all tissues. E2F factors binding to the upstream domain IV region of the promoter have been shown to be involved in the expression of POMC in SCLC. We show that these sites are methylated in normal nonexpressing tissues, which will prevent binding of E2F, but are unmethylated in expressing tissue. Methylation in vitro is sufficient for silencing of expression, which is not reversed by treatment with Trichostatin A, suggesting that inhibition of expression may be mediated by means other than recruitment of histone deacetylase activity. The DMS-79 cells lack POMC demethylating activity, implying that the methylation and expression patterns are likely to be set early or before neoplastic transformation, and that targeted de novo methylation might be a potential therapeutic strategy.

Topics: Adenoma; Adrenocorticotropic Hormone; Carcinoma, Small Cell; Carrier Proteins; Cell Cycle Proteins; Cell Line; CpG Islands; DNA Methylation; DNA-Binding Proteins; E2F Transcription Factors; Enzyme Inhibitors; Gene Expression; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Lung Neoplasms; Neoplasms; Organ Specificity; Pituitary Neoplasms; Plasmids; Pro-Opiomelanocortin; Promoter Regions, Genetic; Retinoblastoma-Binding Protein 1; Sequence Analysis, DNA; Transcription Factor DP1; Transcription Factors; Transcription, Genetic; Transfection

Histone acetylation has long been associated with transcriptional activation, whereas conversely, deacetylation of histones is associated with gene silencing and transcriptional repression. Here we report that inhibitors of histone deacetylase (HDAC), depsipeptide and trichostatin A, induce apoptotic cell death in human lung cancer cells as demonstrated by DNA flow cytometry and Western immunoblot to detect cleavage of poly(ADP-ribose) polymerase. This HDAC inhibitorinduced apoptosis is greatly enhanced in the presence of the DNA methyltransferase inhibitor, 5-aza-2'-deoxycytidine (DAC). The HDAC inhibitor-induced apoptosis appears to be p53 independent, because no change in apoptotic cell death was observed in H1299 cells that expressed exogenous wild-type p53 (H1299 cells express no endogenous p53 protein). To further investigate the mechanism of DAC-enhanced, HDAC inhibitor-induced apoptosis, we analyzed histone H3 and H4 acetylation by Western immunoblotting. Results showed that depsipeptide induced a dose-dependent acetylation of histones H3 and H4, which was greatly increased in DAC-pretreated cells. By analyzing the acetylation of specific lysine residues at the amino terminus of histone H4 (Ac-5, Ac-8, Ac-12, and Ac-16), we found that the enhancement of HDAC inhibitor-induced acetylation of histones in the DAC-pretreated cells was not lysine site specific. These results demonstrate that DNA methylation status is an important determinant of apoptotic susceptibility to HDAC inhibitors.

Topics: Acetylation; Apoptosis; Azacitidine; Decitabine; DNA Modification Methylases; Drug Synergism; Enzyme Inhibitors; Histone Deacetylase Inhibitors; Histones; Humans; Hydroxamic Acids; Lung Neoplasms; Oligopeptides; Tumor Cells, Cultured; Tumor Suppressor Protein p53

Lung adenocarcinoma cells treated for 16 h with trichostatin A (TSA), an inhibitor of histone deacetylases, and untreated cells were analyzed with respect to differential gene expression. Complex hybridization of cDNA arrays revealed repression of Bcl-xL, CRAB2 and TFIID/TAFII31 as well as induction of p21waf1/cip1, GATA-2, hsp86, ID1, ID2 and ID3 mRNA expression, which could be verified by Northern blotting. ID2 induction was further confirmed by Taqman realtime quantitative RT-PCR. The described alterations of gene expression due to TSA renders the lung adenocarcinoma cells susceptible to induction of apoptosis.

Topics: Adenocarcinoma; bcl-X Protein; Blotting, Northern; Cyclin-Dependent Kinase Inhibitor p21; Cyclins; DNA-Binding Proteins; DNA, Complementary; Enzyme Inhibitors; GATA2 Transcription Factor; Gene Expression Regulation, Neoplastic; HSP90 Heat-Shock Proteins; Humans; Hydroxamic Acids; Inhibitor of Differentiation Protein 1; Inhibitor of Differentiation Protein 2; Inhibitor of Differentiation Proteins; Lung Neoplasms; Neoplasm Proteins; Nucleic Acid Hybridization; Proto-Oncogene Proteins c-bcl-2; Receptors, Retinoic Acid; Repressor Proteins; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; RNA, Neoplasm; TATA-Binding Protein Associated Factors; Trans-Activators; Transcription Factor TFIID; Transcription Factors; Transcription Factors, TFII; Tumor Cells, Cultured