Fig. 9.

CD44^hi cells from K-Ras/p53 compound mutants. a Immunostaining demonstrating the viable cells from K-Ras, p53 mutant tumors are CD44^hi. b Real-time PCR showing that the viable cells in culture are the CD44 mRNA high fraction of the lung tumors. c Real-time PCR showing that knockdown of Zeb1 in cells from a leads to induction of Zeb2 and Pten mRNAs, and with this increase in Zeb2, Tgf-β1 signaling is inhibited. d–d″ Lentiviral infection with Zeb1 shRNA (expressing GFP) causes induction of Zeb2. e Knockdown of Zeb1 leads to induction of E-cadherin (E-cad). f With the increase in Zeb2 upon Zeb1 knockdown, Pten is induced. g Pten induction following Zeb1 knockdown leads to loss of constitutive pS473Akt. h, i Knockdown of Zeb1 leads to loss of cell viability. GFP+ cells show the large, flattened, and multi-nucleated morphology of senescent cells, and according the cells stained for senescent β-galactosidase, as described²⁹