CD44 and breast carcinoma: Putative IFN–CSCs were also detected in AT3 breast carcinoma, namely the CD133+CD44+CD24+low (CD24L, ~3.5 times higher compared with the CTR) and CD133+CD44+CD24+high (CD24H, ~2.6 times higher compared with the CTR) CSC subsets, but we focused on the former, the widely recognized CSC subpopulation in breast carcinoma19 (Fig. 1a).