Genetic characteristics of the non-clear cell renal cancer

Renal cancer (RC) is one of the most frequent diseases in oncological urology; the most common form of RC is the clear cell carcinoma. However, percentage of less-studied non-clear cell RC (nccRC) reaches up to 25 % of cases suggesting further studying, improvement of diagnosis and treatment of these tumors. The key events of carcinogenesis are genetic alterations including chromosomal aberrations and point mutations in proto-oncogenes and tumor suppressor genes. This review describes cytogenetic aberrations in the context of nccRC diversity according to the current ISUP classification. Translocation variants of nccRC (MiT-RC) were characterized separately as particular cases of the chromosome rearrangements involving MiT gene family (TFE3, TFEB, MITF). In addition, the main nccRC hereditary forms caused by germinal mutations in the genes FLCN, FH, and MET, as well as recent studies of sporadic tumors with using the next generation sequencing techniques were reviewed. These experiments were designed to search for somatic mutations throughout the tumor genome or exom and revealed the different mutational profiles of I/II papillary RC subtypes, chromophobe carcinoma versus oncocytoma. The review may be informative for oncologists, urologists, geneticists and specialists in related sciences.