MDM4 and B-cell chronic lymphocytic leukemia: In order to test whether the MDM4-S form is overexpressed in B-CLL, we carried out an initial screening of 36 unselected samples obtained from patients with newly diagnosed B-CLL prior to undergoing standard chemoimmunotherapy with fludarabine, cyclophosphamide, and rituximab (i.e. FCR regimen) at the MD Anderson Cancer Center (Table 1).