Effect of microRNA-145-5p on proliferation, apoptosis and expression of FSCN1 in colon cancer cells

ZHU Lin; ZENG Qingsong; WANG Xu

doi:10.3969/j.issn.1009-0460.2019.11.008

Abstract：Objective To investigate the effect of microRNA-145-5p ( miR-145-5p ) on proliferation, apoptosis and expression of fascin-1 (FSCN1) in colon cancer cells. Methods The miR-145-5p levels of normal human colon epithelium NCM460 cells and colon cancer HCT116 cells were detected by real-time quantitative PCR ( QPCR). HCT116 cells were cultured in vitro and divided into control group, overexpression group and inhibition group. The overexpression group was transfected with miR-145-5p mim-ics, and inhibition group was transfected with miR-145-5p inhibitor, while the control group was not treated specially. The miR-145-5p level, proliferation activity, apoptotic rate and FSCN1 level were detected by QPCR, cell count kit ( CCK)-8, Annexin Ⅴ-FITC／PI double staining flow cytometry and Western blotting. The recombinant psiCHECK2 luciferase report vector carrying wild and mutant 3’ untranslated region (3’UTR) of FSCN1 gene was constructed and the target relationship between miR-145-5p and FSCN1 was verified by double luciferase reporter gene system. Results The miR-145-5p level in HCT116 cells was 0. 281± 0. 072, lower than 1. 062± 0. 226 in NCM460 cells (P＜0. 05). Compared with 1. 103±0. 214 in control group, the miR-145-5p level in overexpression group in-creased to 4. 159±1. 080, while that in inhibition group decreased to 0. 348±0. 052; compared with control group, the proliferation ac-tivity in the overexpression group decreased at 48 and 72 h after transfection, while those in inhibition group increased; compared with (7. 539±1. 413)% in control group, the apoptotic rate in overexpression group increased to (17. 126±4. 274)%, while that in inhibi-tion group decreased to (2. 658±0. 725)%; compared with 0. 521±0. 078 in control group, the FSCN1 level in overexpression group decreased to 0. 243±0. 034, while that in inhibition group increased to 0. 769±0. 092; the difference among groups was statistically sig-nificant (P＜0. 05). Compared with the luciferase reporter vector carrying the mutant FSCN1 3’UTR, miR-145-5p mimics could reduce the luciferase activity of the wild type containing FSCN1 3’UTR (P＜0. 05), but had no effect on the mutant (P＞0. 05). Conclusion MiR-145-5p is low expression in colon cancer cells and plays a role of tumor suppressor gene. This miRNA may regulate the prolifer-ation of cancer cells and promote their apoptosis by targeting FSCN1, which is expected to become a target of diagnosis and new bio- therapy for colon cancer.