Cdk5 inhibition impairs cancer cell growth.(A) Proliferation of non-targeting (nt) or Cdk5 shRNA-transduced cells is shown (mean±s.e.m., *P<0.001, n=3). Immunoblots of non-targeting (nt) or Cdk5 shRNA-transduced T24 cells for Cdk5 and β-actin (loading control) proof Cdk5 knockdown. (B) Proliferation of MCF10A, MCF7, T24, MDA-MB-231, epithelial and mesenchymal HMLE cells treated with roscovitine for 72 h at indicated concentrations is shown. EC50 values for the various cell lines are indicated. (C) Viability of MCF10A, MCF7, T24, MDA-MB-231, epithelial and mesenchymal HMLE cells treated with roscovitine for 24 h at indicated concentrations is shown. (D) Colony formation of non-targeting (nt) and Cdk5 shRNA T24 cells after 7 days is shown. Bar graph shows quantification (mean±s.e.m., *P<0.001, n=3). (E) Colony formation of T24 cells treated with roscovitine for 24 h before freshly seeding at low density and cultivation for further 7 days is shown. Bar graph shows quantification (mean±s.e.m., *P<0.001, n=3).