DHX9 and ovarian cancer: The connection between the role of BRCA1 (as well as BRCA2) in R-loop resolution and DHX9 helicase was highlighted in a recent study conducted by Patel et al., where deficiency in RNF168, an E3 ubiquitin ligase and a DSB responder that directly ubiquitylates DHX9, resulted in the accumulation of R-loops in BRCA1/2-deficient breast and ovarian cancer cells [279].