RET and familial medullary thyroid carcinoma: Moreover, the authors confirmed the activity of ponatinib against RET in different cell models, by using HEK293 stable clones expressing four disease-associated oncogenic mutants of RET, namely RETC634R (frequently found in multiple endocrine neoplasia 2A), RETM918T (associated with multiple endocrine neoplasia 2B), RETV804L and RETV804M (isolated in familial medullary thyroid carcinoma patients).