XL 188 is a potent and selective USP7 inhibitor with IC 50 values of 90 nM and 193 nM for USP7 full-length and catalytic domain enzyme, respectively. XL 188 can be used in research of cancer. In Vitro XL 188 (1-20 μM; 16 h; MCF7 cells) promotes USP7 dependent loss of HDM2 and increase of p53 and p21. MCE has not independently confirmed the accuracy of these methods. They are for reference only. Western Blot AnalysisCell Line: MCF7 cells Concentration: 1, 5, 10, and 20μM Incubation Time: 16 hours Result: Had the loss of HDM2 accompanied by an increase in downstream tumor suppressors p21 and p53. Form:Solid