Dataset Information

HDAC inhibitors target HDAC5, upregulate microRNA-125a-5p, and induce apoptosis in breast cancer cells.

ABSTRACT: Histone deacetylase inhibitors (HDACi) are novel clinical anticancer drugs that inhibit HDAC gene expression and induce cell apoptosis in human cancers. Nevertheless, the detailed mechanism or the downstream HDAC targets by which HDACi mediates apoptosis in human breast cancer cells remains unclear. Here, we show that HDACi reduce tumorigenesis and induce intrinsic apoptosis of human breast cancer cells through the microRNA miR-125a-5p in vivo and in vitro. Intrinsic apoptosis was activated by the caspase 9/3 signaling pathway. In addition, HDACi mediated the expression of miR-125a-5p by activating RUNX3/p300/HDAC5 complex. Subsequently, miR-125a-5p silenced HDAC5 post-transcriptionally in the cells treated with HDACi. Thus, a regulatory loop may exist in human breast cancer cells involving miR-125a-5p and HDAC5 that is controlled by RUNX3 signaling. Silencing of miR-125a-5p and RUNX3 inhibited cancer progression and activated apoptosis, but silencing of HDAC5 had a converse effect. In conclusion, we demonstrate a possible new mechanism by which HDACi influence tumorigenesis and apoptosis via downregulation of miR-125a-5p expression. This study provides clinical implications in cancer chemotherapy using HDACi.

SUBMITTER: Hsieh TH

PROVIDER: S-EPMC4395776 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

HDAC inhibitors target HDAC5, upregulate microRNA-125a-5p, and induce apoptosis in breast cancer cells.

Hsieh Tsung-Hua TH Hsu Chia-Yi CY Tsai Cheng-Fang CF Long Cheng-Yu CY Wu Chin-Hu CH Wu Deng-Chyang DC Lee Jau-Nan JN Chang Wei-Chun WC Tsai Eing-Mei EM

Molecular therapy : the journal of the American Society of Gene Therapy 20141222 4

Histone deacetylase inhibitors (HDACi) are novel clinical anticancer drugs that inhibit HDAC gene expression and induce cell apoptosis in human cancers. Nevertheless, the detailed mechanism or the downstream HDAC targets by which HDACi mediates apoptosis in human breast cancer cells remains unclear. Here, we show that HDACi reduce tumorigenesis and induce intrinsic apoptosis of human breast cancer cells through the microRNA miR-125a-5p in vivo and in vitro. Intrinsic apoptosis was activated by t ...[more]

PMID: 25531695

Similar Datasets

Project description:The identification of recurrent somatic mutations in genes encoding epigenetic enzymes has provided a strong rationale for the development of compounds that target the epigenome for the treatment of cancer. This notion is supported by biochemical studies demonstrating aberrant recruitment of epigenetic enzymes such as histone deacetylases (HDACs) and histone methyltransferases to promoter regions through association with oncogenic fusion proteins such as PML-RARα and AML1-ETO. HDAC inhibitors (HDACi) are potent inducers of tumor cell apoptosis; however, it remains unclear why tumor cells are more sensitive to HDACi-induced cell death than normal cells. Herein, we assessed the biological and molecular responses of isogenic normal and transformed cells to the FDA-approved HDACi vorinostat and romidepsin. Both HDACi selectively killed cells of diverse tissue origin that had been transformed through the serial introduction of different oncogenes. Time-course microarray expression profiling revealed that normal and transformed cells transcriptionally responded to vorinostat treatment. Over 4200 genes responded differently to vorinostat in normal and transformed cells and gene ontology and pathway analyses identified a tumor-cell-selective pro-apoptotic gene-expression signature that consisted of BCL2 family genes. In particular, HDACi induced tumor-cell-selective upregulation of the pro-apoptotic gene BMF and downregulation of the pro-survival gene BCL2A1 encoding BFL-1. Maintenance of BFL-1 levels in transformed cells through forced expression conferred vorinostat resistance, indicating that specific and selective engagement of the intrinsic apoptotic pathway underlies the tumor-cell-selective apoptotic activities of these agents. The ability of HDACi to affect the growth and survival of tumor cells whilst leaving normal cells relatively unharmed is fundamental to their successful clinical application. This study provides new insight into the transcriptional effects of HDACi in human donor-matched normal and transformed cells, and implicates specific molecules and pathways in the tumor-selective cytotoxic activity of these compounds.

Project description:Cervical cancer (CC), also known as invasive cervical carcinoma, is one of the most common gynecologic malignancies. The aim of the present study was to investigate the function of microRNA (miR)-125a-5p on CC progression and cisplatin (DDP) resistance. For this purpose, reverse transcription-quantitative PCR (RT-qPCR) was used to assess the expression of miR-125a-5p and LIMK1 in CC tissues, corresponding normal tissues and cells (human CC cell lines: C-33A, CaSKi; human cervical epithelial cells: HUCEC). Cisplatin (DDP) resistant cervical cancer cell lines were established (C-33A/DDP and CaSKi/DDP cell lines). RT-qPCR results demonstrated that miR-125a-5p or LIM kinase 1 (LIMK1) expression was downregulated or upregulated in C-33A/DDP and CaSKi/DDP cells, respectively. MTT assay, flow cytometry analysis and Western blotting were employed to detect the proliferation, apoptosis rate, IC50 of DDP and the expression of drug resistance-related proteins (P-glycoprotein and glutathione S-transferase-π). The targeting relationship between miR-125a-5p and LIMK1 was confirmed by the TargetScan database and dual-luciferase reporter gene assay. In CC tissues and cell lines, compared with normal tissues or HUCEC, miR-125a-5p expression was downregulated and LIMK1 expression was upregulated. The transfection with miR-125a-5p mimics decreased the proliferation of CaSKi/DDP cells, increased the apoptosis rate, reduced the IC50 of DDP, and downregulated the expression of drug resistance-related proteins; conversely, LIMK1 overexpression decreased the apoptosis rate, increased the IC50 of DDP, and upregulated the expression of drug resistance-related proteins. The luciferase reporter gene assay demonstrated that miR-125a-5p targeted and negatively regulated LIMK1. miR-125a-5p could partially reverse the effect of LIMK1 on the proliferation, apoptosis, IC50 of DDP and the expressions of drug resistance-related proteins. The findings of the present study indicated that miR-125a-5p sensitizes CC cells to DDP by targeting LIMK1, hence increasing the anticancer efficacy of cisplatin.

Dataset Information

HDAC inhibitors target HDAC5, upregulate microRNA-125a-5p, and induce apoptosis in breast cancer cells.

Publications

HDAC inhibitors target HDAC5, upregulate microRNA-125a-5p, and induce apoptosis in breast cancer cells.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets