A Study on the Correlations of the miR-31 Expression with the Pathogenesis and Prognosis of Head and Neck Squamous Cell Carcinoma.

Objective: To investigate the correlations of miR-31 expression with cell proliferation, invasion, and prognosis of patients with head and neck squamous cell carcinoma (HNSCC).

Methods: The expression of miR-31 in human laryngeal cancer TU686 cells, human nasopharyngeal carcinoma CNE-2 cells, and normal human oral keratinocyte (NHOK) epithelial cells was detected via quantitative real-time polymerase chain reaction (qRT-PCR). The effects of miR-31 on the proliferation and invasion of HNSCC cells were explored through transfecting miR-31 analogs (miR-31 mimics) and miR-31 inhibitors (anti-miR-31). qRT-PCR was applied to detect the expressions of miR-31 in 56 cases of HNSCC tumor tissues and tumor-adjacent normal tissues. The correlation of miR-31 expression with pathological parameters and survival prognosis of HNSCC patients was also analyzed.

Results: The expressions of miR-31 in TU686 and CNE-2 cell lines were significantly higher than that in NHOK cells (p < 0.01). Compared with those in the negative control group, the proliferation and invasion abilities of cells transfected with miR-31 mimics were notably enhanced (p < 0.01), and those of cells transfected with anti-miR-31 were significantly reduced (p < 0.01). In addition, miR-31 mimics significantly reduced ARID1A expression (p < 0.01) and anti-miR-31 increased its expression (p < 0.05). The expression of miR-31 in tumor tissues of HNSCC patients was remarkably higher than that in tumor-adjacent normal tissues (p < 0.01). This, together with clinical data analysis, revealed that the expression of miR-31 was associated with tumor differentiation, metastasis, and staging of patients, and the survival period of patients with lowly expressed miR-31 was longer.

Conclusions: The highly expressed miR-31 can stimulate the proliferation and invasion of HNSCC cells, closely correlated with tumor differentiation, metastasis, and staging of patients. Patients with lowly expressed miR-31 have a longer survival period. Therefore, miR-31 expression can be taken as a crucial reference indicator for the prognosis of HNSCC patients.