In an attempt to elucidate the mechanism(s) through which PDPN affects the EMT pathway in papillary thyroid cancer, we studied the expression of several proteins involved in the E/R/M and EMT pathways following PDPN silencing in TPC1 and BcPAP thyroid cancer cell lines, i.e. CD44, RhoA, Snail, Twist1, Vimentin, Paxillin and PTK2. This evidence concerns the gene TWIST1 and thyroid cancer.