Dactolisib (BEZ235), a PI3K inhibitor, and RAF265, a RAF inhibitor active against VEGFR2, were tested, and both drugs considerably inhibited their kinase targets and strongly inhibited proliferation of DTC (but also MTC) cell lines with mutations in RAS, BRAF, ret proto-oncogene (RET), and PTEN [90]. Here, RET is linked to medullary thyroid gland carcinoma.