Fig. 1.

CD24⁺ cells demonstrate significantly higher levels of the IGF1R. a Western blot analysis of IGF1R expression in Mvt1 cells infected with control or IGF1R shRNA as indicated. b Protein expression was quantified relative to β-actin expression by densitometric analysis. c Control and IGF1R-KD cells were injected into the fourth mammary fat pad of 8-week-old virgin female FVB/N mice (50,000 cells/mouse) and tumor volume was measured during a 5-week period. d Western blot analysis of IGF1R expression in CD24^- and CD24⁺ Mvt1 cells. e Protein expression was quantified relative to β-actin expression by densitometric analysis. The Mann-Whitney test was performed to compare the difference in IGF1R between CD24⁺ and CD24⁺ cells ***P < 0.001. IGF1R insulin-like growth factor receptor, KD knockdown