trichostatin-a and Adenocarcinoma-of-Lung

Metastasis is a leading cause of mortality in patients with lung adenocarcinoma. Histone deacetylases have emerged as promising targets for anti-tumor drugs, with histone deacetylase inhibitors (HDACi) being an active area of research. However, the precise mechanisms by which HDACi inhibits lung cancer metastasis remain incompletely understood. In this study, we employed a range of techniques, including qPCR, immunoblotting, co-immunoprecipitation, chromatin-immunoprecipitation, and cell migration assays, in conjunction with online database analysis, to investigate the role of HDACi and HDAC2/YY1 in the process of lung adenocarcinoma migration. The present study has demonstrated that both trichostatin A (TSA) and sodium butyrate (NaBu) significantly inhibit the invasion and migration of lung cancer cells via Histone deacetylase 2 (HDAC2). Overexpression of HDAC2 promotes lung cancer cell migration, whereas shHDAC2 effectively inhibits it. Further investigation revealed that HDAC2 interacts with YY1 and deacetylates Lysine 27 and Lysine9 of Histone 3, thereby inhibiting Cdh1 transcriptional activity and promoting cell migration. These findings have shed light on a novel functional mechanism of HDAC2/YY1 in lung adenocarcinoma cell migration.

Topics: Adenocarcinoma of Lung; Animals; Antigens, CD; Butyric Acid; Cadherins; Cell Movement; Epithelial-Mesenchymal Transition; Female; Gene Expression Regulation, Neoplastic; Histone Deacetylase 2; Histone Deacetylase Inhibitors; Humans; Mice; Neoplasm Metastasis; Protein Binding; Transcription, Genetic; Transforming Growth Factor beta; YY1 Transcription Factor

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

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

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

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

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