Figure 6
Up-regulation of Sox2 and its downstream targets is accompanied by enhanced tumorigenic properties in YB-1 down-regulated RR cells. (A) Mammosphere assay formation efficiency of MCF7 Unsorted cells after 72-hour 20 nM of scrambled or YB-1 siRNAs. (B) Mammosphere and soft agar colony forming efficiency of MCF7 RU and RR cells after 72-hour 20 nM of scrambled or YB-1 siRNAs. (C) Luciferase assay results of collected MCF7 RU and RR 7-day mammospheres formed after 72-hour 20 nM of scrambled or YB-1 siRNAs normalized to the RU cells siScr treatment luciferase value. (D) Mammosphere assay formation efficiency of MCF7 Unsorted cells after 72-hour 20 nM treatment of scrambled or YB-1 siRNA #2, and accompanying quantitative-RT-PCR analyses of relative mRNA transcripts of YBX1 (YB-1), SOX2, NANOG, CCND1 (Cyclin D1), and ITGA6 (CD49f) from resulting mammospheres after 7-day mammosphere culture and previous 72-hour 20 nM scrambled or YB-1 siRNA #2. YB-1 siRNA #2 was used here as it showed superior knockdown efficiency in the 7-day mammosphere culture conditions.