KDM6A variants with cancer-derived mutations were generated using site directed mutagenesis and fused to eGFP serving as an all-in-one affinity and fluorescence tag to study demethylase activity by an ELISA-based assay in vitro, apoptosis by FACS, complex assembly by Co-immunoprecipitation and localization by microscopy in urothelial cells and apoptosis by FACS. This evidence concerns the gene MBD2 and cancer.