To investigate the expression levels of Ras guanine nucleotide release factor 1 (RASGRF1) in colorectal cancer tissues and the related influencing factors of its low expression.

Sixty-two cases with colorectal cancer were selected as the research objects from April 2012 to January 2015. The colorectal cancer tissues and normal colon tissue samples beside cancerous lesions were obtained by surgery. The expression levels of RASGRF1 in tissue samples were detected by immunohistochemistry. According to the results of examination, the subjects were divided into the low expression group (group A) and high expression group (group B). The clinical data were retrospectively analyzed. For those indexes with significant differences after univariate analysis, non-conditional Logistic regression analysis was performed.

①The positive expression rate of RASGRF1 in colorectal cancer tissues (59.7%) was significantly lower than that in normal colon tissues beside cancerous lesions(96.8%) (χ²=25.046, P=0.000). The low expression rate of RASGRF1 in colorectal cancer tissues (61.3%) was significantly higher than that in normal colon tissues beside cancerous lesions (41.9%) (χ²=4.650, P=0.031). ②In group A (38 cases), there were 24 female cases (63.2%), 28 patients (73.7%) at stage Ⅲ-Ⅳ of TNM staging and 25 patients (65.8%) with distant metastases, which were all significantly higher than those in group B [24 cases totally, 11 cases (45.8%), 6 cases (25.0%), and 4 cases (16.7%), respectively] (P<0.05). ③Non-conditional Logistic regression analysis showed that gender (female), TNM staging (stage Ⅲ-Ⅳ) and distant metastasis were the related influencing factors of low expression of RASGRF1 in colorectal cancer tissues (P<0.05).

The expression level of RASGRF1 in colorectal cancer tissues is lower. TNM staging, distant metastasis and gender are the related influencing factors of low expression of RASGRF1 in colorectal cancer tissues.