DSB proteins and their regulator in various cancers. We have shown DSB related E3 ligases mentioned in several cancers and how they function in regulating cancer cell. For example, the DSB related E3 ligases RNF20/40, RNF8, RNF126, RNF138, RNF168, RNF169, BRCA1, FBXW7, HERC2, WWP2 are shown to regulate various cancer cell DSB repair by targeting substrates for ubiquitination.