In particular, the results indicate a more consistent inhibitory effect of vitamin D on CCL2 secretion, which was observed in both thyroid cell types and at several concentrations tested, as compared to CXCL8, which was reduced only in TPC-1 and only by using the highest concentration of vitamin D. This observation would indicate that different pathways are involved in the secretion of CXCL8 and CCL2 in thyroid cancer cells. This evidence concerns the gene CCL2 and thyroid gland carcinoma.