Expression levels and clinical significance of microR-495-3p and Holliday junction recognition protein in thyroid cancer

  Objective  To detect the expression levels of microRNA-495-3p (miR-495-3p) and Holliday junction recognition protein (HJURP) in thyroid cancer tissues and explore their clinical significance.

  Methods  A total of 67 paraffin-embedded specimens of thyroid cancer diagnosed by pathological examination and 42 paraffin-embedded specimens of normal thyroid tissue were selected as research objects. The miR-495-3p level was detected with fluorescence quantitative polymerase chain reaction (PCR) technology, the positive expression of HJURP was detected by immunohistochemistry, the relationships of miR-495-3p, HJURP levels with clinicopathological parameters in patients with thyroid cancer were analyzed. Kaplan-Meier survival curve was used to analyze the relationships of the levels of miR-495-3p and HJURP in thyroid cancer with the prognosis ofpatients; COX regression analysis was used to explore the adverse factors affecting the prognosis of thyroid cancer patients.

  Results  The positive expression rate of HJURP in cancer tissues was 62.69%, and was 26.19% in normal thyroid tissues (P < 0.01); the relative expression of miR-495-3p in thyroid cancer tissue and normal thyroid tissue was (0.76±0.21) and (1.26±0.40), respectively(t=8.539, P < 0.001); the levels of miR-495-3p and HJURP were related to the clinical stageand lymph node metastasis of thyroid patients (P < 0.05). The levels of miR-495-3p in patients with thyroid cancer in clinical stage of Ⅲ to Ⅳ and lymph nodemetastasis were lower, and their positive expression of HJURP protein were higher; the 3-year cumulative survival rates of patients with miR-495-3p high expression were significantly higher than in those with miR-495-3p low expression (χ²=8.478, P=0.004); the 3-year cumulative survival rate of patients with positive HJURP was significantly lower than that in those with negative HJURP (57.14% versus 92.00%, χ²=9.093, P=0.003); the results of multivariate analysis showed that clinical staging, lymph node metastasis, miR-495-3p, and HJURP were independent risk factors affecting the poor prognosis of patients with thyroid cancer (P < 0.05).

  Conclusion  In tissues of thyroid cancer, the expression of miR-495-3p is down-regulated, and the expression of HJURP is up-regulated, which are related to the clinical stage of the tumor, lymph node metastasis and prognosis, and may be involved in the differentiation and migration of tumor cells.