Identification of PTK7 as a promising therapeutic target for thyroid cancer.

OBJECTIVE To evaluate the possible involvement of PTK7 in the progression of human thyroid cancer and assess its potential effects on the proliferation and apoptosis of thyroid cancer. PATIENTS AND METHODS Immunohistochemical (IHC) assays and clinical significance analysis were performed to explore the correlations between PTK7 expression and clinical characteristics of patients with thyroid cancer. Quantitative PCR assays and Immunoblot assays were performed to detect the expression of PTK7 in control or PTK7 shRNA plasmids transfected thyroid cancer cells. MTT assays were performed to detect the effects on the proliferation of thyroid cancer cells. Flow cytometry (FCM) assays were performed to assess the changes in cell apoptosis of thyroid cancer. Additionally, the effects of PTK7 on tumor growth were detected through in vivo tumor growth assays. RESULTS PTK7 is highly expressed in human thyroid cancer tissues, and its expression levels are associated with the clinical characteristics, including TNM stage (p=0.015*), and intraglandular dissemination (p=0.024*) of patients with thyroid cancer. PTK7 ablation inhibits cell proliferation and stimulates cell apoptosis of thyroid cancer in vitro. Additionally, PTK7 contributes to tumor growth of thyroid cancer cells in mice. CONCLUSIONS We demonstrated the involvement of PTK7in the progression of thyroid cancer, and therefore provided a novel and promising therapeutic target for thyroid cancer treatment.