To investigate the correlation between the expression of integrin β3 (ITGB3, an important vascular endothelial cell marker) and lymph node metastasis in colorectal cancer patients.

Immunohistochemical (IHC) staining was used to detect the expression of ITGB3 in cancer tissues, normal mucosa tissues adjacent to cancer and corresponding lymph node tissues of 49 patients with primary colorectal cancer. Thirty-seven patients had lymph node metastasis. The correlation between ITGB3 expression and cancer metastasis was analyzed.

IHC results showed that ITGB3 positive immunoreaction was mainly observed in the cytoplasm of primary colorectal cancer, normal mucosa adjacent to cancer and mesenchyme of corresponding lymph nodes. ITGB3 had different expression in different tissues. The expression of ITGB3 in cancer tissues was significantly lower than that in normal tissues adjacent to cancer, with a statistically significant difference (P<0.01). The expression of ITGB3 in lymph nodes of metastatic group was significantly higher than that of non-metastatic group, with a statistically significant difference (P<0.001). There was a positive correlation between the expression of ITGB3 in lymph node epithelial cells and the expression in lymph node interstitial tissue (r=0.395, P=0.005). In lymph node metastatic group, there was a positive correlation between the expression of ITGB3 in epithelial cells of cancer tissue and the expression in lymph node epithelial cells (r=0.514, P=0.001). The expressions of ITGB3 in lymph nodes, epithelial cells and mesenchyme were positively correlated with lymph node metastasis.

The expression of ITGB3 in lymph nodes are positively correlated with colorectal cancer lymph node metastasis. ITGB3 may be a potential molecular marker for lymph node metastasis in patients with primary colorectal cancer.