Screening and functional analysis of micro-RNAs that regulate the expression of the tumor suppression TP53 gene.

Abstract

With gradual increase of cancer incidence and mortality rates, the regulatory mechanism of cancer has become a hotspot. It has been known that the expression of TP53 is closely associated with the occurrence of cancer. The microRNA (miRNA)-mediated regulation of the expression of numerous proto-oncogenes has been reported. This study aimed to identify miRNAs that regulate the expression of TP53 gene. The sequence of TP53 gene was downloaded from NCBI and analyzed with TargetScan software to predict potential miRNAs that regulate TP53 expression. miR-122 was selected as the most potential miRNA for regulating TP53. miR-122 mimics and inhibitor were synthesized and transfected into Hela cells. The expression of TP53 mRNA was measured by qRT-PCR. The cell proliferation, migration, and invasion ability were assessed by CCK-8, scratch wounding, and transwell invasion assay, respectively. Cells transfected with miR-122 mimics exhibited significantly lower TP53 expression (p < 0.05), but significantly increased cell proliferation and migration compared with blank control group (p < 0.05). Notably, cells in miR-122 mimics and control groups had similar invasion ability (p > 0.05). However, cells in miR-122 inhibitor group exhibited significantly higher TP53 expression (p < 0.05), but significantly reduced cell proliferation and invasion ability. The migration ability of cells in miR-122 inhibitor group was similar to cells in control group (p > 0.05). The selected miR-122 effectively inhibited the expression of TP53 gene in Hela cells, and enhanced their proliferation, migration, and invasion.