Oncogenic miR-544 is an Important Molecular Target in Gastric Cancer
Qiaoming Zhi, Xiaobo Guo, Lei Guo, Rongjuan Zhang, Jinling Jiang, Jun Ji, Jianian Zhang, Jun Zhang, Xuehua Chen, Qu Cai, jianfang Li, Bingya Liu, Zhenggang Zhu and Yingyan Yu
MicroRNAs (miRNAs) and promoter hypermethylation are vital epigenetic mechanisms for transcriptional inactivation of
tumor suppressor. IRX1 is a newly identified tumor suppressor gene and hypermethylation involves the decreased expression in gastric
cancer. However, the microRNA regulatory mechanism on IRX1 expression is still unclear. In this study, we report an IRX1-targeting
miRNA-544, which directly targets 3'-UTR of IRX1 gene by luciferase reporter assay. miR-544 suppresses the protein expression of
IRX1 gene by Western blot and immunocytochemistry. Ectopic expression of miR-544 promotes cell proliferation and cell cycle
progression significantly in vitro on gastric cancer cells. The study suggests that miR-544 is an oncogenic microRNA in gastric cancer.
Over expression of miR-544 contributes to the inactivation and low-expression of IRX1 in gastric cancer. These findings are helpful for
clarifying the molecular mechanisms involved in gastric carcinogenesis and indicate that miR-544 is a key regulator in switching cell
cycle on or off. miR-544 may be a potential molecular target in miRNA-based strategy on gastric cancer.
Gastric cancer, IRX1, MiR-544, Oncogenic microRNA
Department of Surgery, Shanghai Institute of Digestive Surgery, Ruijin Hospital, Shanghai Jiao Tong University, School of Medicine, Ruijin er Road, No. 197, 200025, Shanghai