MTOR and nonpapillary renal cell carcinoma: Speaking against these arguments are the many molecular and cellular overlaps between the mouse models and human ccRCC19,20,36 as well as the fact that the VpR model and the Vhl/Pbrm1/Keap1/Tsc1 model are therapeutically sensitive to mTOR inhibition19,36, which induces therapeutic effects in at least some cases of human ccRCC and the VpR model is also sensitive to anti-VEGF sunitinib therapy19, which is also efficacious in some human ccRCCs.