An elevation of IGF1R phosphorylation at Tyr1131, the major autophosphorylation site, was observed in various RCC cells lacking MTAP (Fig. 4b, left), whereas inhibition of IGF1R activity was observed in ACHN cells overexpressing V5-tagged wild-type MTAP but not in cells transfected with D220A-mutated MTAP (Fig. 4b, right). Here, IGF1R is linked to renal cell carcinoma.