Upregulated CNTN1 is associated with lymph node metastasis and poor prognosis of colorectal cancer

Contactin1 (CNTN1), a member of the immunoglobulin superfamily, is known to correlate with tumor development and progression. Although recent studies have found that elevated CNTN1 has been demonstrated in some types of cancers, the expression and prognosis of CNTN1 in colorectal cancer (CRC) are unclear. Here, we aimed to determine the clinicopathological characteristics and prognostic role of CNTN1 in CRC patients.The protein expression of CNTN1 in tumor tissues was evaluated by immunohistochemistry. In addition, the mRNA and protein expressions of CNTN1 were examined by qRT-PCR and Western blotting analysis in 40 matched adjacent normal mucosa samples. The relationships of CNTN1 with clinicopathological data and prognosis significance were analyzed.Immunohistochemical consequence suggested that the protein level of CNTN1 was obviously raised in CRC compared with adjacent normal mucosa tissues (56.9% vs 10.3%, P< 0.05). In addition, we detected a significant increase in CNTN1 mRNA and protein levels in CRC tissues compared with the matched adjacent normal mucosa tissues. Moreover, increased CNTN1 exprssion was significantly associated with tumor size, lymph node metastasis (LNM), tumor node-metastasis (TNM) stage and carcino-embryonic antigen (CEA) in clinical analysis. Kaplan-Meier analysis suggested that patients with CNTN1 over-expression showed worse overall survival (OS) (P= 0.001). Multivariate analysis indicated that high CNTN1 expression was an independent predictor for poor OS in CRC patients (P= 0.028). Further analysis revealed that patients with high CNTN1 combined with LNM present accurately predicted poorer outcome.Taken together, the findingsindicate that CNTN1 plays a significant role and serve as a potential biomarker for the prediction of adverse prognosis in CRC. Intriguingly, high express of CNTN1 + LNM-present combination may improve the accuracy of prognosis.