MicroRNA192 Promotes Metastasis and Invasion of Breast Cancer via Targeting Tensin1 and Enhancing Cell Division Control Protein 42 Homolog (CDC42) Expression

Abstract

We aimed to dissect the biological impacts and mechanisms of MicroRNA192 in breast cancer metastasis and invasion. Tumor tissues from patients and breast cancer cells were used to measure miR-192 level via RT-PCR. The miR-192 mimics, miR-192 inhibitor, si-Tensin1 and corresponding negative controls were transfected into cells followed by analysis of cell invasion by transwell assay and CDC42 level by western blot. Afterwards, a tumor transplantation model was established to assess the malignancy progression and migration. The human miR-192 accounted for approximately 14% of those overexpressed miRNAs. Overexpression of miR-192 promoted malignant cell invasion, while knockdown of endogenous miR-192 significantly decreased cell invasion, which suggested that miR-192 could exert a promotive factor in the invasive characteristic of breast cancer cells in vitro. In contrast to control group, tumor metastasis was significantly provoked in the miR-192 overexpression group. miR-192 directly targeted and suppressed the expression of Tensin1. miR-192 enhanced the malignant invasiveness by regulating Cdc42 and was corrected with correlation with the survival of patients. High miR-192 level is related to the malignant invasiveness and metastatic behavior, as well as the poor prognosis of patients with breast cancer via activating Cdc42 and targeting Tensin1.