Furthermore, athymic nude mice receiving MCF-7 cells infected by lentiviruses carrying empty vectors or MCF-7 cells with lentivirus-delivered Eg5, RNF20, or RNF40 knockdown, the tumor growth was significantly suppressed compared with control mice, suggesting that an RNF20/40-Eg5 axis is involved in breast carcinogenesis [109]. This evidence concerns the gene RNF40 and neoplasm.