Expression of ITGB1 predicts prognosis in colorectal cancer: a large prospective study based on tissue microarray.

Background: ITGB1 is a heterodimeric cell-surface receptor involved in cell functions such as proliferation, migration, invasion and survival. The aim of this study was to assess ITGB1 expression in colorectal cancer and correlate it with clinicopathological features, as well as to evaluate its potential prognostic significance. Materials and methods: In this study, we examined the expression of ITGB1 using tissue microarrays containing analyzed specimens by immunohistochemistry. ITGB1 expression was further correlated with clinicopathological and prognostic data. The prognostic significance was assessed using Kaplan-Meier survival estimates and log-rank tests. A multivariate study with the Cox’s proportional hazard model was used to evaluate the prognostic aspects. Results: ITGB1 expression was present in 88.5% of the analyzed specimens. Significant differences in ITGB1 expression were found between normal mucosa and carcinomas (P<0.001). High ITGB1 expression was associated with poor prognosis, and it independently correlated with shortened overall survival and disease-free survival in colorectal cancer patients (P<0.001). More so, ITGB1 expression, bowel wall invasion, lymph node metastasis and distant metastasis were independent prognostic factors for overall survival. Additionally, significant differences in ITGB1 expression were observed in adenomas and tumors from patients with familial adenomatous polyposis compared to normal colon mucosa (P<0.05) Conclusion: The results of this study indicate that ITGB1 overexpression in colorectal tumors is associated with poor prognosis, as well as aggressive clinicopathological features. Therefore, ITGB1 expression could be used as potential prognostic predictor in colorectal cancer patients.