Figure 1
Expression levels of anti-apoptotic Bcl-2 proteins in human CRC. (a) IHC staining against Bcl-xL, Mcl-1 and Bcl-2 on a TMA, containing normal mucosa (n=13), adenoma (n=22) and adenocarcinoma tissue (n=61). Exemplary spots of mucosal and adenocarcinomal tissue are shown. Scale bar indicates magnification for all panels. (b) Evaluation of staining intensities by multiplying values for staining quantity and quality. All P-values are calculated using mucosa as control group. Bcl-xL is significantly overexpressed in adenomas (P=0.007) and adenocarcinomas (P=0.0002), Mcl-1 shows a decreased expression whereas Bcl-2 shows no deregulated expression. (c) Significant increase of Bcl-xL expression in CRC tissue compared with the corresponding normal mucosa (P=0.01), determined by western blot analysis and subsequent densitometric evaluation (T=Tumor, M=Mucosa, Pat=Patient; n=13 patients in total). Exemplary western blot of four patients is shown. Values are expressed as means+S.D. *P<0.05; **P<0.01; ***P<0.001
