First, we examined the expression of KRT19 in human thyroid follicular epithelial cells (Nthy-ori 3 − 1) and two human papillary thyroid carcinoma cells (TPC-1 and KTC-1) by Western Blot and further verified that KRT19 expression was significantly up-regulated in human PTC cells. The gene discussed is KRT19; the disease is differentiated thyroid carcinoma.