Similarly, suppression of wild-type CDK12 in Ewing sarcoma cells driven by the EWS/FLI fusion oncoprotein, a potent transcriptional activator and transforming gene in this disease, using type VI inhibitor THZ531 (a selective covalent inhibitor of CDK12/13) preferentially decreased expression of DDR genes and was synergistic with PARP inhibitors [271]. This evidence concerns the gene CDK12 and Ewing sarcoma.