Thyroid cancer cells OCUT1, K1, FTC133, C643, Hth7, and TPC1 harbored PIK3CA, PTEN, Ras, or RET/PTC mutations that could activate the PI3K/Akt pathway. MK2206 inhibited the proliferation of all these cells with IC50 values in the low micromolar range, mostly below or around 0.5 μm....Genotypes of thyroid cell lines and their sensitivities to MK2206.