CD44 and breast cancer: Additionally, we evaluated the breast cancer stem cell phenotype (CD44+CD24−) using flow cytometry and found a higher percent of total events of the phenotype CD44+CD24− in BCCs co-cultured with shCtrl obASCs compared to BCCs co-cultured with shLep obASCs or control BCCs in both MCF7 and ZR-75, while T47D showed no difference in the CD44+CD24− cell phenotype between groups and overall had almost undetectable levels of this cancer stem cell phenotype through flow cytometry (Figure 4C).