Association between B-cell-specific Moloney murine leukemia virus integration site-1 expression and clinical characteristics in colorectal cancer

Objective To investigate B-cell-specific Moloney murine leukemia virus integration site-1 (Bmi-1) expression and its prognostic significance in colorectal cancer. Methods Bmi-1 expression in tumor tissue and the corresponding tissue was detected using immunohistological staining. The correlations between Bmi-1 expression and clinicopathological characteristics and the survival time were analyzed. Results The median H-scores of Bmi-1 in colorectal cancer tissues and normal tissues were 87.5 (0-270) and 5 (0-90) respectively, with statistically significant difference (χ2=17.275, P=0.000). Bmi-1 expression in colorectal cancer tissues was not statistically associated with gender, age, tumor size, pathological grade, stage, lymph node metastasis or distant metastasis. The average survival time of patients with high and low Bmi-1 expression was 51.0 (46.7-54.4) and 55.6 (52.1-59.1) months respectively, with no statistically significant difference (χ2=2.500, P=0.114). Conclusion Bmi-1 expression in colorectal cancer tissue is significantly higher than that in corresponding normal tissue, indicating that Bmi-1 may be involved in the occurrence of colorectal cancer. Key words: B-cell-specific Moloney murine leukemia virus integration site-1; Colorectal cancer; Prognosis