MD-222 (1-30 nM; 1-2 hours) treatment shows very effective in reducing the levels of MDM2 protein and increasing the levels of p53 in a time- and dose-dependent manner in RS4;11 and RS4;11/IRMI-2 cells[1]. MD-222 (30-100 nM; 6 hours) is effective in increasing the expression of several p53-targeted genes, such as MDM2, CDKN1A, and PUMA in RS4;11 cells, indicating strong activation of p53[2]. MD-222 (4 days) shows cell growth inhibitory activity in RS4;11 cells with an IC50 of 5.5 nM, and has no effect on RS4;11/IRMI-2, MDA-MB-231 and MDA-MB-468 cells[1].