Objective:  To investigate the expression of the p16/p38MAPK/p53/Wip1 pathway in patients with papillary thyroid cancer (PTC) and its clinical significance.
Methods: The protein expressions of Wip1， p53， p38MAPK and p16 in 70 cases of PTC tissues and 20 cases of normal thyroid tissues were detected by immunohistochemical staining. The correlations of Wip1 protein high-expression with p53， p38MAPK and p16 protein expression were analyzed.
Results: The high-expression rate of Wip1 protein in the PTC tissue was 64.3% (45/70)， which was significantly different than that in normal thyroid tissue (0/20) (P＜0.01). There were no significant differences between the paired groups in terms of age， gender， tumor size and lymph node metastasis (all P＞0.05). The Wip1 protein high-expression was negatively correlated with the expression of p38MAPK， p53 and p16 (r value was -0.620， 0.356 and 0.550， respectively， and all P＜0.01).
Conclusions: The p16/p38MAPK/p53/Wip1 pathway is abnormal in PTC， and this abnormality may possibly be associated with the aberrantly up-regulated Wip1， which can induce inhibition of p38MAPK， p53 and p16. Wip1 may potentially become a therapeutic target for thyroid cancer.