AXL and thyroid gland carcinoma: Many thyroid cancer cell lines (850-5C, NIM and CAL62) have been demonstrated to express the Axl ligand Gas6.64 In addition, this study showed that human thyroid cancer specimens express Axl and Gas6.64 Specifically, Axl positivity was observed primarily in tumoral cells, while tumoural stroma and nontumoral adjacent tissues were negative.