CG200745, an HDAC inhibitor, induces anti-tumour effects in cholangiocarcinoma cell lines via miRNAs targeting the Hippo pathway

Dawoon E Jung,Chanyang Kim,Si Young Song,Kahee Kim,Soo Been Park

doi:10.1038/s41598-017-11094-3

Abstract

Cholangiocarcinoma is a devastating malignancy with fatal complications that exhibits low response and resistance to chemotherapy. Here, we evaluated the anticancer effects of CG200745, a novel histone deacetylase inhibitor, either alone or in combination with standard chemotherapy drugs in cholangiocarcinoma cells. CG200745 dose-dependently reduced the viability of cholangiocarcinoma cells in vitro and decreased tumour volume and weight in a xenograft model. Administering CG200745 along with other chemotherapeutic agents including gemcitabine, 5-fluorouracil (5-FU), cisplatin, oxaliplatin, or gemcitabine plus cisplatin further decreased cholangiocarcinoma cell viability, with a combination index < 1 that indicated synergistic action. CG200745 also enhanced the sensitivity of gemcitabine-resistant cells to gemcitabine and 5-FU, thereby decreasing cell viability and inducing apoptosis. This was accompanied by downregulation of YAP, TEAD4, TGF-β2, SMAD3, NOTCH3, HES5, Axl, and Gas6 and upregulation of the miRNAs miR-22-3p, miR-22-5p, miR-194-5p, miR-194-3p, miR-194-5p, miR-210-3p, and miR-509-3p. The Ingenuity Pathway Analysis revealed that CG200745 mainly targets the Hippo signalling pathway by inducing miR-509-3p expression. Thus, CG200745 inhibits cholangiocarcinoma growth in vitro and in vivo, and acts synergistically when administered in combination with standard chemotherapeutic agents, enabling dose reduction. CG200745 is therefore expected to improve the outcome of cholangiocarcinoma patients who exhibit resistance to conventional therapies.

Highlights

Cholangiocarcinoma is the second most common primary hepatobiliary cancer and has a poor prognosis, with 5-year survival rates in the range of 5% to 15%1–3
A previous study showed that treatment with histone deacetylases (HDACs) inhibitor combined with other chemotherapy drugs resulted in an enhanced anti-proliferative effect and reduced toxicity in cholangiocarcinoma cells, and we recently demonstrated that CG200745 has anti-proliferative and synergistic effects in pancreatic cancer cells[19, 20]
CG200745 inhibited the expression of multidrug resistance (MDR) genes including ABCG2 and multidrug resistance-associated protein (MRP)[4]; human equilibrative nucleoside transporter[1]; the ATP-binding cassette (ABC) transporters MRP1 and MRP3; and HDAC class II isozymes including HDAC4 and HDAC7 in SNU-1196, SNU-1196/GR, and SNU-308 cells (Figs 1e,f and. 3d,e)

Summary

Introduction

Cholangiocarcinoma is the second most common primary hepatobiliary cancer and has a poor prognosis, with 5-year survival rates in the range of 5% to 15%1–3. Gemcitabine-based regimens are considered as standard treatment for cholangiocarcinoma patients[4, 5]. HDAC inhibitors are anti-cancer drugs that acetylate lysine residues in the N-terminal tails of histones, which inhibits their association with DNA and induces the expression of tumour suppressor genes. CG200745 is an intravenous hydroxamate-based pan-HDAC inhibitor similar to vorinostat[10] whose anti-proliferative effect has been demonstrated in several types of cancer cells, including prostate cancer, renal cell carcinoma, and colon cancer, either alone or in combination with other chemotherapy drugs. A previous study showed that treatment with HDAC inhibitor combined with other chemotherapy drugs resulted in an enhanced anti-proliferative effect and reduced toxicity in cholangiocarcinoma cells, and we recently demonstrated that CG200745 has anti-proliferative and synergistic effects in pancreatic cancer cells[19, 20]. We analysed gene expression with cDNA and miRNA microarrays to clarify the molecular mechanisms underlying CG200745 action

Methods

Results

Conclusion