Aberrant Expression of miR-142-3p and its Target Gene HMGA1 and FZD7 in Breast Cancer and its Clinical Significance.

BACKGROUND

Breast cancer is the second leading cause of cancer-related death among women worldwide. The aim of this study is to investigate the role of miR-142-3p in breast cancer cells and the related mechanism.

METHODS

Sixty paired breast cancer tissues were collected and 60 breast tissues from patients with mammary hyperplasia served as the control group. The expression of miR-142-3p was examined using RT-qPCR methods; moreover, we also performed receiver operating characteristic (ROC) curve analysis to determine whether miR142-3p can distinguish breast cancer patients from the controls. Next, HMGA1 and FZD7 have been predicted as target genes of miR-142-3p, and the expressions of HMGA1 and FZD7 in breast cancer tissue and the control group were examined using RT-qPCR and western blot methods.

RESULTS

miR-142-3p was significantly down-regulated in breast cancer tissue compared with the controls, and the levels of miR-142-3p was negatively correlated with the tumor size, degree of differentiation, and metastasis (p < 0.01). Moreover, results of ROC curve analysis indicated that the expression of miR-142-3p can distinguish between patients with breast cancer and the control group (AUC = 0.819, 95% CI, 0.756 - 0.881). Furthermore, the expressions of HMGA1 and FZD7 were significantly up-regulated in patients with breast cancer compared with the controls. The level of miR-142-3p was negatively correlated with expressions of HMGA1 (r = -0.3507, p = 0.006) and FZD7 (r = -0.3410, p = 0.0077) in patients with breast cancer.

CONCLUSIONS

Our results proved that miR-142-3p may serve as a tumor suppressor in breast cancer by suppressing the expression of oncogene HMGA1 and FZD7, suggesting that miR-142-3p has the potential to become a diagnostic marker and therapeutic target for the early diagnosis and treatment of breast cancer.