Noxa upregulation and 5‐gene apoptotic biomarker panel in colorectal cancer

Background NOXA and MCL1 are involved in the intrinsic pathway of apoptosis, where Noxa selectively binds to MCL1 and prevents it from inhibiting apoptosis. Both factors are considered as potential tumour biomarkers, while MCL1 has attracted interest as target in cancer. The purpose of this study was to investigate the expression of NOXA and MCL1 in 160 CRC tumour samples, to investigate their significance, also in combination with IAPs, DR5 expression and KRAS gene mutations in CRC. Materials and methods Fresh frozen colorectal tissue was obtained from patients undergoing surgery for CRC. Real‐time quantitative PCR was performed for the determination of mRNA expression levels. Protein expression was determined immunohistochemically. Differences in the mRNA expression profile were evaluated with the nonparametric Wilcoxon signed ranks test. Statistical analysis was performed with the use of Mann‐Whitney U test and receiver‐operating characteristic (ROC) curve. Results NOXA was found to be overexpressed in CRC tumours (P