Figure 5.

The impact of ILK on resistance formation in W1 and W1CR cells as a potential target for sensitization: (a,b) The expression of ILK in W1 (a) and W1CR (b) cells upon the indicated treatment regimens was detected by Western blot. Data indicate that W1 cells react to COL1 by higher ILK expression, which can obviously counterbalance the cytotoxic stress of cisplatin. The W1CR cells only marginally react to COL1 by deregulated ILK, but the combination of cisplatin with COL1 is indicated by a massive upregulation. (c,d) Blocking ILK by the small molecule inhibitor cdp22 at 1 µM concentration in W1 cells (c) clearly reversed the resistance effects of COL1, indicated by the EC₅₀ values of cisplatin for the respective treatment regimes; while for the W1CR cells (d), no sensitivity is detectable. Data are means of at least n = 3 (±SEM), asterisks indicate statistical significance: ** p < 0.01; *** p < 0.001.