Figure 6. Pharmacological T-type Ca2+ channel blockade induces up-regulation of p21CIP1.
Whole cell lysates from TE10, TE8, and KYSE510 cells with or without mibefradil (3 μmol/L) treatment for 48 h (A), and TE8 cells treated for 48 h with a series of mibefradil concentrations (0, 1.5, 3, and 4.5 μmol/L) (B) were separated by 10% SDS-PAGE and immunoblotted with anti-p21CIP1 antibody. Equal loading of the gel was confirmed by ponceau S staining in A (data not shown) or β-tubulin in B. Quantification was performed by densitometry (n=3 each; * P < 0.05). A, Shows that p21CIP1 expression was increased in TE8 cells but not in TE10 and KYSE510 cells. B, Shows that the increase in p21CIP1 expression in TE8 cells following mibefradil treatment was in a dose-dependent manner.