trichostatin-a and Endometrial-Neoplasms

Endometrial cancer is increasingly prevalent in western societies and affects mainly postmenopausal women; notably incidence rates have been rising by 1.9% per year on average since 2005. Although the early-stage endometrial cancer can be effectively managed with surgery, more advanced stages of the disease require multimodality treatment with varying results. In recent years, endometrial cancer has been extensively studied at the molecular level in an attempt to develop effective therapies. Recently, a family of compounds that alter epigenetic expression, namely histone deacetylase inhibitors, have shown promise as possible therapeutic agents in endometrial cancer. The present review aims to discuss the therapeutic potential of these agents.. This literature review was performed using the MEDLINE database; the search terms histone, deacetylase, inhibitors, endometrial, targeted therapies for endometrial cancer were employed to identify relevant studies. We only reviewed English language publications and also considered studies that were not entirely focused on endometrial cancer. Ultimately, sixty-four articles published until January 2018 were incorporated into our review.. Studies in cell cultures have demonstrated that histone deacetylase inhibitors exert their antineoplastic activity by promoting expression of p21WAF1 and p27KIP1, cyclin-dependent kinase inhibitors, that have important roles in cell cycle regulation; importantly, the transcription of specific genes (e.g., E-cadherin, PTEN) that are commonly silenced in endometrial cancer is also enhanced. In addition to these abstracts effects, novel compounds with histone deacetylase inhibitor activity (e.g., scriptaid, trichostatin, entinostat) have also demonstrated significant antineoplastic activity both in vitro and in vivo, by liming tumor growth, inducing apoptosis, inhibiting angiogenesis and potentiating the effects of chemotherapy.. The applications of histone deacetylase inhibitors in endometrial cancer appear promising; nonetheless, additional trials are necessary to establish the therapeutic role, clinical utility, and safety of these promising compounds.

Topics: Antineoplastic Agents; Endometrial Neoplasms; Endometrium; Female; Histone Deacetylase Inhibitors; Histone Deacetylases; Humans; Hydroxamic Acids; Hydroxylamines; Quinolines

Epigenetic changes in cancer and precancerous lesions could be utilized as biomarkers for cancer early detection. This study aims to investigate the novel biomarkers in endometrial carcinoma, and explore their epigenetic regulation.. Methylation of six tumor suppressor genes (CDH13, SHP1, HIN1, DKK3, CTNNA1 and PCDH8) was evaluated in 155 endometrium samples. Changes of methylation and mRNA expression after treatment with 5-Aza-2'-deoxycytidine (5-Aza-CdR) or/and trichostatin A (TSA) were investigated by MSP and qRT-PCR respectively. Co-immunoprecipitation was used to detect the interactions between UHRF1 and PRMT5 proteins.. CDH13 and SHP1 promoters were highly methylated (81.36% and 86.44%, respectively) in endometrial carcinoma, while CDH13 promoter methylation was also present in complex hyperplasia and atypical hyperplasia (51.72% and 50.00%, respectively). Methylation of CDH13 and SHP1 promoters was associated with age and tumor differentiation or muscular infiltration depth. CDH13 and SHP1 promoters were completely methylated in endometrial carcinoma cell lines and were partially reversed by 5-Aza-CdR or TSA to induce mRNA levels (P<0.01). After combined treatment with these two agents, methylation of CDH13 and SHP1 promoters was completely reversed and expression of their mRNA was significantly increased (P<0.01). Moreover, PRMT5 could bind to UHRF1 and down-regulated by 5-Aza-CdR and/or TSA treatment (P<0.05).. Our data demonstrate for the first time that SHP1 methylation has high specificity for diagnosis of endometrial carcinoma, while CDH13 promoter methylation plays a role in the earlier stage. Furthermore, UHRF1 could form a complex with PRMT5 to contribute to the endometrial carcinogenesis.

Topics: Azacitidine; Cadherins; CCAAT-Enhancer-Binding Proteins; Cell Line, Tumor; Decitabine; DNA Methylation; Endometrial Neoplasms; Female; Genes, Tumor Suppressor; Humans; Hydroxamic Acids; Middle Aged; Promoter Regions, Genetic; Protein Tyrosine Phosphatase, Non-Receptor Type 6; Protein-Arginine N-Methyltransferases; RNA, Messenger; Ubiquitin-Protein Ligases; Up-Regulation

DNA methyltransferase (DNMT) and histone deacetylase are key enzymes mediating the epigenetic regulation of gene expression. DNA hypermethylation and/or histone deacetylation in promoter regions is often associated with downregulation or silencing of transcription. Epigenetic silencing of tumor suppressor genes plays an important role in malignant transformation. DNMT and HDAC inhibitors induce DNA demethylation and histone acetylation, respectively, leading to reactivation of silenced genes, and dramatic morphological and functional changes in cancer cells. In this study, we have conducted a series of experiments to characterize the effects of epigenetic inhibitors in endometrial cancer cells. Using cell lines representing different stages of endometrioid cancers, we examined the impact of DNMT inhibitor, ADC, and HDAC inhibitor, TSA, on cell cycle and apoptosis. We found that while both reagents were capable of inhibiting cell proliferation and inducing cell apoptosis, TSA appeared to be a more potent apoptosis inducer, but with a smaller effect on cell cycle. On the other hand, ADC exhibited strong effects on cell cycle regulation, but had smaller impact on cell apoptosis. We subsequently confirmed the presence of a strong synergism between DNMT and HDAC inhibitors. Thus, ADC and TSA exhibited strong cytostatic and apoptotic effects in endometrial cancer cell lines and the combined application may deliver the highest response in the clinical setting.

Topics: Antineoplastic Agents; Apoptosis; Azacitidine; Cell Cycle; Cell Line, Tumor; Cell Proliferation; DNA (Cytosine-5-)-Methyltransferases; DNA Methylation; Endometrial Neoplasms; Enzyme Inhibitors; Epigenesis, Genetic; Female; Histone Deacetylase Inhibitors; Histone Deacetylases; Humans; Hydroxamic Acids; Neoplasm Staging

To understand the epigenetic mechanism underlying the PR-B gene silencing in endometrial cancer (EC) cells, we compared the chromatin composition between transcriptionally active and silenced PR-B genes in EC cell lines and cancer tissues.. Chromatin Immunoprecipitation (ChIP) assay was performed to measure MBD occupancy and histone acetylation/methylation in transcriptionally active and silenced PR-B genes. PR-B-positive/-negative, as well as epigenetic inhibitor-treated/-untreated EC cells were used as study models. Real-time polymerase chain reaction (PCR) and Western blot analysis were applied to measure the mRNA and protein levels of PR-B, MBD, and histones.. A close association among PR-B methylation, MBD binding and PR-B gene silencing was observed. Treatment with epigenetic inhibitors led to dynamic changes in the PR-B chromatin composition and gene expression. Increased H3/H4 acetylation and H3-K4 methylation, and decreased H3-K9 methylation were found to be associated with re-activation of silenced PR-B genes. MeCP2 knockdown resulted in a decreased MeCP2 binding to PR-B genes and an increased PR-B expression. ChIP analysis of MeCP2 binding to PR-B genes in the PR-B-positive/-negative EC samples confirmed the significant role of MeCP2 in PR-B silencing.. PR-B gene expression is regulated by a concerted action of epigenetic factors including DNA methylation, MBD binding, and histone modifications. MeCP2 occupancy of PR-B genes plays a critical role in PR-B gene silencing. These findings enriched our knowledge of the epigenetic regulation of PR-B expression in EC, and suggested that the epigenetic re-activation of PR-B could be explored as a potential strategy to sensitize the PR-B-negative endometrial cancers to progestational therapy.

Topics: Adenocarcinoma; Azacitidine; Cell Line, Tumor; Chromatin Immunoprecipitation; CpG Islands; DNA Methylation; DNA-Binding Proteins; Endometrial Neoplasms; Female; Gene Expression Regulation, Neoplastic; Gene Silencing; Histone Deacetylase Inhibitors; Histones; Humans; Hydroxamic Acids; Methyl-CpG-Binding Protein 2; Neoplasm Proteins; Protein Binding; Protein Interaction Mapping; Real-Time Polymerase Chain Reaction; Receptors, Progesterone; RNA, Messenger; RNA, Neoplasm; RNA, Small Interfering; Transcription Factors

An exciting recent approach to targeting transcription factors in cancer is to block formation of oncogenic complexes. We investigated whether interfering with the interaction of the transcription factor SALL4, which is critical for leukemic cell survival, and its epigenetic partner complex represents a novel therapeutic approach. The mechanism of SALL4 in promoting leukemogenesis is at least in part mediated by its repression of the tumor suppressor phosphatase and tensin homolog deleted on chromosome 10 (PTEN) through its interaction with a histone deacetylase (HDAC) complex. In this study, we demonstrate that a peptide can compete with SALL4 in interacting with the HDAC complex and reverse its effect on PTEN repression. Treating SALL4-expressing malignant cells with this peptide leads to cell death that can be rescued by a PTEN inhibitor. The antileukemic effect of this peptide can be confirmed on primary human leukemia cells in culture and in vivo, and is identical to that of down-regulation of SALL4 in these cells using an RNAi approach. In summary, our results demonstrate a novel peptide that can block the specific interaction between SALL4 and its epigenetic HDAC complex in regulating its target gene, PTEN. Furthermore, targeting SALL4 with this approach could be an innovative approach in treating leukemia.

Topics: Animals; Carcinoma, Hepatocellular; Drug Design; Endometrial Neoplasms; Epigenesis, Genetic; Female; Gene Expression Regulation, Leukemic; Histone Deacetylase 1; Histone Deacetylase 2; Histone Deacetylase Inhibitors; HL-60 Cells; Humans; Hydroxamic Acids; Leukemia, Monocytic, Acute; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Leukemia, Myeloid, Acute; Liver Neoplasms; Male; Mice; Mice, Inbred NOD; Mice, SCID; Peptide Fragments; Proto-Oncogene Proteins c-akt; PTEN Phosphohydrolase; Transcription Factors; Xenograft Model Antitumor Assays

Histone deacetylase (HDAC) inhibitors are emerging as a novel class of anti-tumor agents and have manifested the ability to decrease proliferation and increase apoptosis in different cancer cells. A significant number of genes have been identified as potential effectors responsible for the anti-tumor function of HDAC inhibitor. However, the molecular mechanisms of these HDAC inhibitors in this process remain largely undefined. In the current study, we searched for microRNAs (miRs) that were affected by HDAC inhibitor trichostatin (TSA) and investigated their effects in endometrial cancer (EMC) cells. Our data showed that TSA significantly inhibited the growth of EMC cells and induced their apoptosis. Among the miRNAs that altered in the presence of TSA, the miR-106b-93-25 cluster, together with its host gene MCM7, were obviously down-regulated in EMC cells. p21 and BIM, which were identified as target genes of miR-106b-93-25 cluster, increased in TSA treated tumor cells and were responsible for cell cycle arrest and apoptosis. We further identified MYC as a regulator of miR-106b-93-25 cluster and demonstrated its down-regulation in the presence of TSA resulted in the reduction of miR-106b-93-25 cluster and up-regulation of p21 and BIM. More important, we found miR-106b-93-25 cluster was up-regulated in clinical EMC samples in association with the overexpression of MCM7 and MYC and the down-regulation of p21 and BIM. Thus our studies strongly indicated TSA inhibited EMC cell growth and induced cell apoptosis and cell cycle arrest at least partially through the down-regulation of the miR-106b-93-25 cluster and up-regulation of it's target genes p21 and BIM via MYC.

Topics: Apoptosis; Apoptosis Regulatory Proteins; Bcl-2-Like Protein 11; Cell Cycle Proteins; Cell Line, Tumor; Cell Proliferation; Cyclin-Dependent Kinase Inhibitor p21; DNA-Binding Proteins; Down-Regulation; E-Box Elements; Endometrial Neoplasms; Female; Gene Expression Regulation, Neoplastic; Humans; Hydroxamic Acids; Membrane Proteins; MicroRNAs; Minichromosome Maintenance Complex Component 7; Multigene Family; Nuclear Proteins; Promoter Regions, Genetic; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-myc; RNA, Messenger

Overexpression of histone deacetylases has been reported in various human malignancies; however, the expression of histone deacetylases in endometrial tissue is not fully understood. In the present study, the expression of histone deacetylase 1, histone deacetylase 2, and Ki-67 was examined immunohistochemically in 30 normal and 66 malignant endometrial tissue samples. The results were expressed as a positivity index and compared with the positivity index for Ki-67 and rates of patient survival. The effect of 2 histone deacetylase inhibitors, trichostatin A and apicidine, on cell proliferation and the expression of cell cycle regulators such as cyclins (D1, E, and A), p21, p27, and p16 were investigated using 6 endometrial carcinoma cell lines. The positivity index for histone deacetylase 1 (79.8 +/- 33.0, mean +/- SD) and histone deacetylase 2 (106.3 +/- 41.9) was higher in endometrial carcinoma than the normal endometrium, with a significant difference for histone deacetylase 2. The positivity index for histone deacetylase 2 was significantly increased in higher-grade carcinomas (positivity index for grade 3, 124.9 +/- 28.4) compared with grade 1 tumors (86.0 +/- 41.0) and was positively correlated with that for Ki-67. In addition, patients with histone deacetylase 2-positive carcinomas had a poor prognosis compared with those with histone deacetylase 2-negative carcinoma (P = .048). Treatment with trichostatin A or apicidine suppressed the proliferation in all cell lines examined, in association with increased expression of p21 and down-regulation of cyclin D1 and cyclin A expression. These results indicated that increased histone deacetylase 2 expression is involved in the acquisition of aggressive behavior by endometrial carcinoma and suggest histone deacetylase inhibitor to be a promising anticancer drug for this carcinoma.

Topics: Adult; Aged; Apoptosis; Cell Cycle Proteins; Cell Line, Tumor; Cell Proliferation; Endometrial Neoplasms; Endometrium; Female; Histone Deacetylase 1; Histone Deacetylase 2; Humans; Hydroxamic Acids; Immunohistochemistry; Ki-67 Antigen; Middle Aged; Peptides, Cyclic; Prognosis; Survival Analysis

Patients suffered from advanced endometrial cancer have poor prognosis. The five-year survival is only 25%. Histone deacetylase inhibitors have shown promise in the treatment for a variety of malignancies. In combination with traditional cytotoxic chemotherapy, histone deacetylase inhibitors can enhance the survival rate of cancer patients. This study was to investigate the effect and mechanism of trichostatin A (TSA), a histone deacetylase inhibitor, combined with paclitaxel (PTX) on the apoptosis of human endometrial carcinoma cell line Ark2.. Ark2 cells were cultured in RPMI-1640 and treated with PTX alone, TSA alone or the two drugs in combination. Cell apoptosis was detected using Annexin V and Hoechst staining; perturbation of mitochondrial membrane potential was detected using MitoTracker red Poly (ADP-ribose) polymerase; caspase-9 degradation products and tubulin acetylation were detected by Western blot.. Results of Annexin V showed that PTX (1.5 nmol/L) plus TSA (25 nmol/L) induced a significantly higher apoptotic rate (45.2%) than PTX alone (14.1%) or TSA alone (11.2%) did in Ark2 cells after drug treatment for three days. The results of Hoechst staining and Annexin V were consistent. A loss of mitochondrial membrane potential could activate the apoptotic cascade. Cleavages of PARP and caspase-9 were significantly apparent in PTX plus TSA group than in PTX group or TSA group (P<0.05). PTX and TSA could induce tubulin acetylation. PTX in combination with TSA increased acetylated tublins and microtubule stability compared with either drug alone. The loss of mitochondrial membrane potential was more dramatic in the drug combination group than the single drug group. The effects of TSA and PTX were synergistic (q=2.54).. TSA and PTX could induce apoptosis of Ark2 cells, which may be through the loss of mitochondrial membrane potential and acetylation of non-histone proteins induced by histone deacetylase inhibitors.

Topics: Acetylation; Antineoplastic Agents, Phytogenic; Apoptosis; Caspase 9; Cell Line, Tumor; Cystadenocarcinoma, Serous; Drug Synergism; Endometrial Neoplasms; Female; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Membrane Potential, Mitochondrial; Microtubules; Paclitaxel; Poly(ADP-ribose) Polymerases; Tubulin

To investigate the effects of trichostatin A (TSA) and paclitaxel (PTX) on the apoptosis and microtubulin stabilization in human endometrial carcinoma cells and its mechanism.. Human endometrial carcinoma cells of the line Ark2, KLE and AN3 were cultured in the presence of TSA (TSA group), or PTX (PTX group), or TSA plus PTX (TSA + PTX group) respectively. The growth curve was obtained by trypan-blue exclusion assay. Apoptosis was observed by annexin V and Hoechst staining. Perturbation of mitochondrial membrane potential (MMP) was detected by flow cytometry. Western blotting was used to detect the protein expression of caspase-9, poly ADP-ribose polymerase (PARP), and acetylated microtubulin.. The growth of the Ark2, KLE, and AN3 cells of the TSA, PTX, and TSA + PTX group, especially in the latter group, was inhibited. The Ark2 cell apoptotic rates 4 days later of the TSA, PTX, TSA + PTX, and control group were 4.25% +/- 0.25%, 12.12% +/- 0.62%, 16.56% +/- 0.74%, and 46.78% +/- 2.68% respectively by annexin V staining, and 3.39% +/- 0.12%, 6.00% +/- 0.25%, 10.05% +/- 0.53%, and 22.30% +/- 1.25% respectively by Hoechst staining. The apoptotic rates of the TSA + PTX group by both staining methods were both significantly higher than those of the other groups (all P < 0.05). Lysis of caspase-9 and PARP in the Ark2 and KLE cells increased greatly 24 hours after the TSA and PTX treatment. The disappearance rate of MMP in the Ark2 and AN3 cells of the TSA + PTX groups were 16.80% +/- 0.92% and 11.28% +/- 0.78% respectively, significantly higher than that of the PTX group (5.34% +/- 0.45% and 5.61% +/- 0.56% respectively) and TSA group (4.96% +/- 0.47% and 6.46% +/- 0.62% respectively, all P < 0.05). The expression of acetylated microtubulin was increased in the Ark2 and KLE cells of the TSA + PTX groups.. Synergy of TSA and PTX inhibits the cell growth and induces apoptosis. The acetylation of non-histone protein induced by histone deacetylase inhibitor is one of the possible mechanisms of its anti-cancer effects.

Topics: Apoptosis; Cell Line, Tumor; Endometrial Neoplasms; Female; Humans; Hydroxamic Acids; Microtubule Proteins; Microtubules; Paclitaxel

Histone deacetylase inhibitors (HDACIs) have recently emerged as promising anticancer drugs to induce cell cycle arrest, cytodifferentiation, and apoptosis. It is suggested, however, that HDACIs promote cell migration and invasion depending on the cell type. We have reported previously that treatment with HDACIs, including trichostatin A and suberoylanilide hydroxamic acid (SAHA) or progesterone in combination with estrogen, can induce cytodifferentiation of endometrial adenocarcinoma Ishikawa cells through up-regulation of glycodelin, a progesterone-induced endometrial glycoprotein. Given the reported role of glycodelin in cell motility and the migration-modulating potential of HDACIs, we investigated using wound healing assay and transwell migration assay whether ovarian steroid hormones, trichostatin A, or SAHA affects cell migration in endometrial cancer cell lines, Ishikawa and RL95-2. Treatment with ovarian steroid hormones, trichostatin A, and SAHA enhanced cell migration together with up-regulation of glycodelin. SAHA-augmented cell migration was almost completely blocked by gene silencing of glycodelin. Furthermore, overexpression of gycodelin alone resulted in increased cell motility in Ishikawa cells. Our results collectively indicate that glycodelin positively regulates cell motility acting as a mediator of HDACI-enhanced endometrial cell migration, suggesting the involvement of glycodelin in the dynamic endometrial gland morphogenesis during menstrual cycle. Our results raise a possibility that the use of HDACIs in the therapy for glycodelin-inducible endometrial and presumably other gynecological cancers may enhance invasion in cases in which the HDACIs fail to exert differentiation-inducing and/or antiproliferative effects.

Topics: Adenocarcinoma; Antineoplastic Agents; Cell Line, Tumor; Cell Movement; Endometrial Neoplasms; Enzyme Inhibitors; Female; Fibronectins; Glycodelin; Glycoproteins; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Ovary; Pregnancy Proteins; Up-Regulation; Vorinostat

The use of histone deacetylase (HDAC) inhibitors has shown promise for a variety of malignancies. In this investigation, we define the activity of this class of inhibitors in combination with traditional cytotoxic chemotherapy in endometrial cancer cells. Significant reductions in growth were observed in Ark2 and KLE endometrial cancer cells following treatment with paclitaxel, doxorubicin, carboplatin, or the HDAC inhibitor trichostatin A (TSA). However, only combined treatment with TSA/paclitaxel caused synergistic inhibition of cell growth. This combination also resulted in significant changes in cell morphology. Using cell cycle analysis, nuclear staining, and Western blot analysis for poly(ADP-ribose) polymerase and caspase-9 degradation products, TSA/paclitaxel showed the most dramatic activation of the apoptotic cascade. These effects were also observed when the HDAC inhibitors HDAC inhibitor-1 or oxamflatin were substituted for TSA. The anticancer properties of paclitaxel are known to result in part from inhibition of microtubule depolymerization, which results in apoptosis. We show that TSA administration also stabilizes microtubules via alpha-tubulin acetylation. Furthermore, using Western blot and immunohistochemical analysis, treatment with TSA/paclitaxel led to a significant increase in acetylated tubulin and microtubule stabilization. These effects were confirmed in a mouse xenograft model. Moreover, TSA/paclitaxel resulted in a 50% reduction in tumor weight compared with either agent alone. This study provides in vivo evidence of nonhistone protein acetylation as one possible mechanism by which HDAC inhibitors reduce cancer growth. The TSA/paclitaxel combination seems to hold promise for the treatment of serous endometrial carcinoma and other malignancies with limited sensitivity to paclitaxel.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Caspase 9; Drug Synergism; Endometrial Neoplasms; Enzyme Inhibitors; Female; Histone Deacetylase Inhibitors; Histone Deacetylases; Humans; Hydroxamic Acids; Mice; Mice, Nude; Microtubules; Paclitaxel; Tumor Cells, Cultured

It is well known that the histone deacetylase (HDAC) inhibitor trichostatin A (TSA) acts synergistically with the DNA methyltransferase (DNMT) inhibitor 5-aza-2'-deoxycytidine (ADC) to reactivate DNA methylation-silenced genes. Moreover, in several studies, TSA was capable of inducing DNA demethylation even in the absence of ADC. Here we describe a mechanism by which HDAC inhibitors affect DNA methylation through their regulation on DNMT3B, a methyltransferase responsible for de novo DNA methylation. Using quantitative real-time PCR and Western blot analysis, we show that TSA down-regulates DNMT3B mRNA and protein expression in human endometrial cancer cells. This decrease in DNMT3B mRNA results in a significant reduction in de novo methylation activities. Further experiments indicated that TSA decreases DNMT3B mRNA stability and reduces its half-life from approximately 4 to 2.5 hours. We established that protein synthesis is required for posttranscriptional regulation, suggesting the involvement of an RNase and/or key mRNA stabilization factor(s) controlling the DNMT3B mRNA stability. Therefore, TSA may not only modify histone acetylation, but also potentially alter DNA methylation. Since the HDAC inhibitors are frequently used in epigenetic studies and are considered to be promising anticancer drugs, these new findings will have implications in both laboratory and clinical settings.

Topics: Azacitidine; Cell Line, Tumor; Decitabine; DNA (Cytosine-5-)-Methyltransferases; Down-Regulation; Endometrial Neoplasms; Female; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; RNA, Messenger

To determine if epigenetic interference can restore progesterone receptor-B (PR-B) expression in PR-B negative endometrial adenocarcinoma cell lines, and to characterize the kinetics of PR-B induction mediated by DNA methyltransferase and histone deacetylase inhibitors.. The PR-B negative endometrioid cancer cell lines KLE and HEC-1B were used as study models. PR-B mRNA and protein expression levels were measured using real-time PCR and Western blot analysis, respectively. DNA methylation levels of the PR-B promoter were determined by methylation-specific PCR. Dose-response correlations and the duration of response to aza-deoxycytidine (ADC) and trichostatin A (TSA) were characterized. Cell responses to prolonged and repeated drug treatment were also examined.. Relatively low concentrations of ADC and TSA over a 24-h period induced PR-B expression. Furthermore, ADC and TSA acted synergistically to reactivate PR-B expression. Depending on the cell line used, PR-B mRNA was induced 10-110 fold. This elevated PR-B expression continued for 48 h after drug withdrawal. Sustained upregulation of PR-B mRNA and protein was observed during prolonged and repeated drug treatment.. The epigenetically silenced PR-B gene remains sensitive to changes in DNA demethylation and histone acetylation in uterine adenocarcinoma cell lines. Treatment with ADC and/or TSA results in a robust and sustainable PR-B upregulation. These small molecule epigenetic modifying agents may be used to sensitize poorly differentiated, PR-B negative endometrial cancers to progestational therapy.

Topics: Adenocarcinoma; Azacitidine; Cell Line, Tumor; Decitabine; DNA Methylation; Endometrial Neoplasms; Enzyme Inhibitors; Epigenesis, Genetic; Female; Histone Deacetylase Inhibitors; Histone Deacetylases; Humans; Hydroxamic Acids; Polymerase Chain Reaction; Receptors, Progesterone; RNA, Messenger; Up-Regulation

Histone reversible acetylation, which is controlled by histone acetyltransferases and deacetylases, plays a fundamental role in gene transcription. Histone deacetylase inhibitors (HDACIs), such as trichostatin A (TSA) and suberoylanilide hydroxamic acid (SAHA), have been characterized not only as anticancer drugs, but also as cytodifferentiation-inducing agents. In human endometrium, postovulatory production of progesterone directs estrogen-primed endometrial glandular cells to differentiate and thereby produce a number of unique bioactive substances, including glycodelin, that are critical for implantation at the secretory phase of the menstrual cycle. In this study, we show that TSA and SAHA, belonging to the hydroxamic acid group of HDACIs, can induce the phenotype of a human endometrial adenocarcinoma cell line, Ishikawa (originally derived from the glandular component of the endometrium), to differentiate to closely resemble normal endometrial epithelium in a time- and dose-dependent manner, as determined by morphological changes, synthesis of glycogen, and expression of secretory phase-specific proteins, including glycodelin. The proliferation- and differentiation-modulating effects elicited by TSA and SAHA at their optimal concentrations were comparable or more potent than those exerted by combined treatment with progesterone and estradiol. Furthermore, the gene silencing of glycodelin by small interference RNA resulted in the blockade of HDACI-induced differentiation in Ishikawa cells, suggesting the requirement for glycodelin for endometrial epithelial differentiation. Our results collectively indicate that TSA and SAHA are potent differentiation inducers for endometrial glandular cells, providing a clue for a possible therapeutic strategy to modulate endometrial function by targeting glycodelin.

Topics: Adenocarcinoma; Cell Differentiation; Cell Line, Tumor; Cell Proliferation; Endometrial Neoplasms; Enzyme Inhibitors; Estradiol; Female; Gene Silencing; Glycodelin; Glycogen; Glycoproteins; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Interleukin-6; Leukemia Inhibitory Factor; Osmolar Concentration; Pregnancy Proteins; Progesterone; Promoter Regions, Genetic; RNA, Messenger; RNA, Small Interfering; Up-Regulation; Vorinostat

HDAC inhibitors (HDACIs) have been shown to inhibit cancer cell proliferation, stimulate apoptosis, and induce cell cycle arrest. Our purpose was to investigate the antiproliferative effects of the HDACIs [suberoyl anilide bishydroxamine, valproic acid (VPA), trichostatin A, and sodium butyrate] against six endometrial cancer cell lines.. Endometrial cancer cells were treated with a variety of HDACIs, and the effect on cell growth, cell cycle, and apoptosis was measured. The ability of VPA to inhibit the growth of endometrial tumors growing in immunodeficient mice was also assessed.. Clonogenic assays showed that all cancer cell lines were sensitive to the growth inhibitory effect of HDACIs. Cell cycle analysis indicated that treatment with HDACIs decreased the proportion of cells in S phase and increased the proportion of cells in the G(0)-G(1) and/or G(2)-M phases of the cell cycle. Terminal deoxynucleotidyl transferase-mediated nick end labeling assays showed that HDACIs induced apoptosis. This was concomitant with altered expression of genes related to malignant phenotype, including an increase in p21(Waf1), p27(Kip7), and E-cadherin and a decrease in Bcl-2 and cyclin-D1 and -D2. Chromatin immunoprecipitation analysis revealed a remarkable increase in levels of acetylated histones associated with the p21 promoter after suberoyl anilide bishydroxamine treatment. In nude mice experiments, VPA inhibited significantly human uterine tumor growth without toxic side effects.. These results suggest that HDACIs are effective in inhibiting growth of endometrial cancer cells in vitro and in nude mice, without toxic side effects. The findings raise the possibility that HDACIs may prove particularly effective in treatment of endometrial cancers.

Topics: Agar; Animals; Antineoplastic Agents; Apoptosis; Blotting, Western; Cadherins; Cell Cycle Proteins; Cell Division; Cell Line, Tumor; Chromatin; Cyclin D1; Cyclin D2; Cyclin-Dependent Kinase Inhibitor p21; Cyclin-Dependent Kinase Inhibitor p27; Cyclins; Dose-Response Relationship, Drug; Endometrial Neoplasms; Enzyme Inhibitors; Female; Flow Cytometry; Histone Deacetylase Inhibitors; Histones; Humans; Hydroxamic Acids; In Situ Nick-End Labeling; Mice; Mice, Nude; Precipitin Tests; Proto-Oncogene Proteins c-bcl-2; S Phase; Sodium Oxybate; Time Factors; Tumor Suppressor Proteins; Valproic Acid; Vorinostat