Expression of B Cell Translocation Gene 1 Protein in Colon Carcinoma and its Clinical Significance

Background: Colon cancer is one of the most common malignant tumors, and B cell Translocation Gene (BTG)1 is involved in the occurrence and development of colon cancer, however, the underlying molecular mechanism remains unclear.

Objective: In this study, we investigated the expression of BTG1 protein in colon cancer, and its association with clinicopathology and prognosis.

Methods: The tumor specimens from 59 patients with colon cancer who had undergone radical colectomy were selected as the observation group. Para-carcinoma tissues from the same patients were selected as the control group. The expressions of BTG1 mRNA and protein in the specimen of two groups were analyzed by quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) and Western blot. According to the immunohistochemical results, the patients were divided into BTG1-negative and BTG1-positive groups. The postoperative cumulative survival rate in the two groups was analyzed. The association of the expression of BTG1 protein with the clinicopathological features and postoperative survival was investigated.

Results: Compared with the control group, the expression levels of BTG1 mRNA and BTG1 protein were significantly decreased in the observation group (P < 0.05). Immunohistochemical analysis revealed that there were 12 positive tumor samples and 47 negative samples. The expression of BTG1 was negatively associated with the degree of differentiation and lymphatic metastasis. The cumulative survival rate of BTG1-positive patients was significantly increased compared with that of BTG1- negative patients (P < 0.05). Stepwise Cox regression analysis showed that lymphatic metastasis, tumor size and BTG1 expression level were independent prognostic factors for overall survival in patients with colon cancer.

Conclusion: BTG1 protein in colon cancer tissues were expressed at low levels, which was associated with the clinicopathological features, postoperative recurrence and survival of patients.