Downregulation of CPT2 promotes tumorigenesis and chemoresistance to cisplatin in hepatocellular carcinoma
Authors Lin MH, Lv D, Zheng YL, Wu ML, Xu C, Zhang Q, Wu LH
Received 21 January 2018
Accepted for publication 26 March 2018
Published 25 May 2018 Volume 2018:11 Pages 3101—3110
Checked for plagiarism Yes
Review by Single-blind
Peer reviewer comments 2
Editor who approved publication: Prof. Dr. Geoffrey Pietersz
Meihua Lin, Duo Lv, Yunliang Zheng, Minglan Wu, Chang Xu, Qiao Zhang, Lihua Wu
Research Center of Clinical Pharmacy, State Key Laboratory for Diagnosis and Treatment of Infectious Disease, First Affiliated Hospital, Zhejiang University, Hangzhou, China
Background: Cancer cells often have characteristic changes in metabolism. Besides Warburg effect, abnormal lipid metabolism is also considered as one of the most typical metabolic symbols of cancer. Thus, understanding the mechanisms of cell metabolic reprogramming may provide a potential avenue for cancer treatment.
Materials and methods: In total, 41 pairs of matched samples of primary hepatocellular carcinoma (HCC) and adjacent non-cancerous liver tissues were collected. Afterward, we performed quantitative reverse transcriptase polymerase chain reaction to investigate carnitine palmitoyltransferase-2 (CPT2) expression and then systematically analyzed its relationship with clinicopathologic features. We further performed proliferation, colony formation, migration and invasion, drug resistance, and lipogenesis assays to determine the function of CPT2 in HCC.
Results: In this study, we have identified CPT2 which is the rate-limiting enzyme of fatty acid oxidation, downregulated in HCC and was significantly associated with tumor histological differentiation and venous invasion. In vitro studies demonstrated that knockdown of CPT2 remarkably enhanced the tumorigenic activity and metastatic potential of hepatoma cells. In addition, CPT2 silencing induced chemoresistance to cisplatin. Mechanistically, low expression of CPT2 promoted cancer cell lipogenesis via upregulation of stearoyl-CoA desaturase-1, the key enzyme involved in the synthesis of monounsaturated fatty acids, at both mRNA and protein levels in hepatoma cell line.
Conclusion: Altogether, our findings demonstrate that CPT2 has a critical role in HCC progression and chemoresistance and may potentially serve as a novel prognostic marker and therapeutic target for HCC treatment.
Keywords: lipid metabolism, CPT2, HCC, SCD1, chemoresistance