Oncotargets in different renal cancer subtypes.

Renal cell cancer is a heterogeneous group of cancers with different histologic subtypes. The majority of renal tumors in adults are clear cell renal cell carcinomas, which are characterized by von Hippel- Lindau (VHL) gene alterations. Recent advances in defining the genetic landscape of renal cancer has shown the genetic heterogeneity of clear cell renal cell carcinomas (ccRCC) and the presence of at least 3 additional ccRCC tumor suppressor genes on chromosome 3p. Due to inactivation of VHL, renal cancer cells produce the HIF-responsive growth factor VEGF. The PI3K--mTORC1 signaling axis also represents a target for therapy. The new systemic therapies, including tyrosine kinase inhibitors, monoclonal antibodies, and mTOR inhibitors, aim to suppress angiogenesis with vascular endothelial growth factor as a target. Various VEGF-inhibitors are approved for the treatment of ccRCC and we discuss recent advancements in the treatment of metastatic ccRCC. Other gene alterations have been identified in hereditary cancer syndromes, e.g. FLCN, TSC1, TSC2, TFE3, TFEB, MITF, FH, SDHB, SDHD, MET, and PTEN and we review their role in renal tumor carcinogenesis, prognosis, and targeted therapy. By reviewing the associations between morphologic features and molecular genetics of renal cancer we provide insight into the basis for targeted renal cancer therapy.