Fig. 4

Inhibition of PLK-1 reduces expression of mutant p53 protein in SW13 cells: Since PLK-1 has been shown to physically interact with p53 to control its functions; the levels of the p53 protein should not be affected after inhibition of PLK-1. a Inhibition of PLK-1 with BI-2536 did not reduce transcript levels of either wild type or mutant p53 as determined by qRT-PCR. b However, BI-2536 treatment resulted in a decrease in the amount of mutant p53 protein in the SW-13 cells, but not of the wild type p53 protein in the H295R cells. c, d Quantitation of PLK-1 and p53 protein westerns after BI-2536 treatment expressed relative to β-actin. This confirms that p53 protein expression decreased in SW-13 and remains constant in H295R. All experiments were done at least 3 individual times and data are represented as means with standard error. The same western blots were stripped and re-probed for multiple proteins. Thus, the blots were cropped for ease of presentation. Uncropped blots with molecular weight standards can be found in the Additional file 1: Figure S2