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

OBJECTIVE: 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.

MATERIALS AND METHODS: 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.

RESULTS: 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).

CONCLUSIONS: The selected miR-122 effectively inhibited the expression of TP53 gene in Hela cells, and enhanced their proliferation, migration, and invasion.