Tumor-suppressor role of miR-139-5p in endometrial cancer.

BACKGROUND

Endometrial cancer (EC) is the fourth most common malignancy of the female genital tract worldwide. MicroRNAs are important gene regulators with critical roles in diverse biological processes, including tumorigenesis. Several study's show that miR-139-5p is involved in the tumorigenesis and metastasis of various cancers. However, its expression and potential biologic role in endometrial cancer remain to be determined. This study aimed to investigate the miR-139-5p expression and to analyze its function and underlying molecular mechanism in endometrial cancer.

METHODS

Expression of miR-139-5p was measured using qRT-PCR. The expression of HOXA10 was detected by Immunofluorescence staining in endometrial cancer tissues and adjacent normal tissues. CCK-8 and colony formation assays were used to assess the effect of miR-139-5p on ECC1 and Ishikawa cell line proliferation. Transwell migration assay was used to study the effect of miR-139-5p on EC cell migration. Luciferase reporter assay and western blot were used to confirm targeting of HOXA10 by miR-139-5p.

RESULT

We demonstrated that miR-139-5p was down-regulated in human endometrial cancer compared to their matched adjacent non-tumor tissues. Overexpressed miR-139-5p significantly inhibited endometrial cancer cell viability and migration. Computational algorithm in combination with dual luciferase reporter assays identified HOXA10 as the target of miR-139-5p. HOXA10 expression was downregulated in endometrial cancer cells after miR-139-5p overexpression. The expression level of HOXA10 was significantly increased in endometrial cancer tissues, which was inversely correlated with miR-139-5p expression in clinical endometrial cancer tissues.

CONCLUSION

These findings indicate that miR-139-5p targets the HOXA10 transcript and suppresses endometrial cancer cell growth and migration, suggesting that miR-139-5p acts as a tumor suppressive role in human endometrial cancer pathogenesis.