Expression of CYP1B1 and B7-H3 significantly correlates with poor prognosis in colorectal cancer patients

Cytochrome P450 1B1 (CYP1B1) is a phase I xenobiotic-metabolizing enzyme (XME) that is overexpressed in colorectal cancer (CRC) tissue, but the prognosis value of CYP1B1 in CRC remains elusive. Additionally, B7-H3 has a key role in tumor cell immune evasion by inhibiting functions of T cells. Thus, in this study, we aimed to identify a new marker for predicting the prognosis of CRC and to study the relationship between tumor metabolism and tumor immunity. We analyzed CYP1B1 and B7-H3 expression in 231 patients with CRC using immunohistochemistry, and we investigated the relationship between CYP1B1 and B7-H3 expression using real-time PCR and Western blot analysis in two human CRC cell lines. Kaplan-Meier survival analysis was used to calculate overall survival (OS) rates, and Cox proportional regression model was performed for multivariate analysis. We found that both CYP1B1 and B7-H3 expression were aberrantly increased in CRC tissues compared to normal colorectal tissues. Moreover, high expression of CYP1B1 was significantly correlated with poor OS, and multivariate analysis indicated that CYP1B1 was a valuable independent prognostic biomarker. Furthermore, CYP1B1 expression was significantly correlated with B7-H3 expression in CRC tissues samples and two human CRC cell lines. In conclusion, these results indicate that CYP1B1 may be a novel predictive biomarker for prognosis of CRC patients, and there is a strong correlation between CYP1B1 and B7-H3 in vivo and in vitro.