Restoration of miR-152 expression suppresses cell proliferation, survival, and migration through inhibition of AKT-ERK pathway in colorectal cancer.

Abstract

MiR-152 has been reported as a tumor suppressor microRNA that is downregulated in a number of cancers, including colorectal cancer (CRC). A recent study suggested that miR-152 could be one of the key regulators of CRC. The aim of this study is to investigate the role of miR-152 in CRC and its mechanisms.The pCMV-GPF-miR-152 vector was transfected into SW-480 and HCT-116 CRC cells via JetPEI transfection reagent. The stable miR-152-expressed cells were selected for the further experiment. To evaluate the effect of miR-152 on cell proliferation, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed. Also, the effect of miR-152 on the survival of CRC cells was analyzed using terminal deoxynucleotidyl transferaseآ dUTP nick-end labeling (TUNEL) assay. The inhibitory effect of miR-152 on migration was assessed by wound healing scratch assay. Then, the proteins expression levels of protein kinase B (AKT), phosphorylated AKT (p-AKT), extracellular signal-regulated kinase (ERK), and phosphorylated ERK (p-ERK) were measured by the western blot analysis method.The result of MTT assay represented miR-152 could inhibit cell proliferation. The TUNEL assay showed miR-152 could induce apoptosis in CRC cells. The wound healing scratch assay showed that miR-152 replacement repressed cell migration in CRC cell lines compared to control groups. The result of protein expression by western blot analysis demonstrated that miR-152 could reduce AKT-p-AKT, and ERK-p-ERK ratio compared to control cells.Our results show that miR-152 has new anticancer and antimetastatic effect in CRC tissue. The current study showed that miR-152 could be a novel therapeutic small molecule to suppress CRC cell proliferation, survival, and migration by suppressing AKT-ERK signaling pathways.