CXCL8 and thyroid cancer: The aim of the present study was to investigate whether vitamin D (1,25-OH2 D3) exerts both direct (cell viability and migration) and indirect (modulation of the pro-tumorigenic chemokines and CXCL8 and/or CCL2 secretion) antitumor effects in TPC-1 and 8505C thyroid cancer cell lines.