Objective: To determine the association between activity of BRAF and mitogen-activated protein/ extracellular signal-regulated kinase kinase (MEK) / extracellular signal-regulated kinase (ERK) signal pathway in papillary thyroid cancer and its mechanism.
Methods: We collected the clinical data and blood samples from 73 cases of papillary thyroid cancer and another 16 cases of benign thyroid gland tumor, and detected the expression of rat sarcoma (RAS), BRAF, MEK1/2, and ERK1/2 in all tumor specimens and benign thyroid tissues with immunohistochemistry and Western blot.
Results: The expression of RAS, BRAF, pMEK1/2, and pERK1/2 protein in papillary thyroid cancer tissues was higher than those in the benign thyroid tissues(P<0.05 or P<0.01). The expression of RAS, BRAF, MEK1/2, and ERK1/2 was associated with the tumor size, the lymph node metastasis, and the clinical stage of papillary thyroid cancer(P<0.05 or P<0.01).
Conclusion: The expression of RAS, BRAF, pMEK1/2, and pERK1/2 is associated with the pathogenesis, the lymph node metastasis, and the clinical stage of papillary thyroid cancer. The MEK/ERK signaling pathway may be activated by BRAF in papillary thyroid cancer.