PTEN and cancer: Candidate genes for a pharmacogenomic stratification of mccRCC include the oncosuppressors TSC1/2 and PTEN, the tumor-drivers PI3K, AKT and mTOR as well as the growth factors released by tumor cells and acting on both the stroma and cancer cells in a paracrine/autocrine fashion, including FGF, PDGF and VEGF.