Figure 6. Analysis of PTEN regulation in in vitro and ex vivo breast cancer models in response to miR106b-cluster and PD 0332991. (A) qRT-PCR analysis of PTEN mRNA (left panel) and immunoblot (right panel). (B) Immunolocalization of PTEN protein in MCF7 cells. (C) qRT-PCR analysis of PTEN mRNA in RB+ and RB- human solid tumors in response to CDK4/6 inhibitors. (D) qRT-PCR analysis of PTEN mRNA in response to ectopic expression of precursor mirR 25, 93 and 106b in MCF7 cells. (E) PTEN 3′ luciferase activity in MCF7 cells in response to PD 0332991 and signals were normalized to renilla luciferase. (F) PTEN 3′ luciferase activity in MCF7 cells in response to ectopic expression of precursor mirR 25, 93 and 106b, and signals were normalized to renilla luciferase. (G) PTEN 3′ luciferase activity in MCF7 cells in response to ectopic expression of anti-mirR 25, 93 and 106b, and signals were normalized to renilla luciferase. Each data point is a mean ± SD from three or more independent experiments. (tumors n = 11 ER+RB+ tumors and 2 ER-RB- tumors.) p < 0.05 were considered as significant.