ReviewPrognostic and clinical significance of claudin-1 in colorectal cancer: A systemic review and meta-analysis

- The studies of claudin-1 expression in colorectal cancer(CRC) have become more and more, whereas there still exist different arguments about the effects of claudin-1 in colorectal cancer.
- Low expression of claudin-1 is associated with TNM III-IV stage and poor prognosis of CRC patients. Low expression of claudin-1 is not associated with gender, depth of invasion, lymph node involvement, tumors' differentiation of CRC patients.
- Claudin-1 is a candidate novel prognostic biomarker for CRC patients.

BackgroundThe current reports on the association of claudin-1 expression with colorectal cancer (CRC) result were controversial. Thus, we conducted a meta-analysis to assess the correlation between claudin-1 expression and the clinical parameters and assess the prognostic value of claudin-1 in CRC.MethodsSystematic searches on PubMed, Embase, Elsevier, CNKI (China National Knowledge Infrastructure), Wanfang data and Cochrane Library prior to August 2016 were performed. The pooled odds ratio (OR) with its 95% confidence interval (95 %CI) was used to assess association between claudin-1 expression and clinical parameters of CRC patients, and to assess association between claudin-1 expression and the prognostic value of CRC patients.ResultsEight studies with a total of 1146 CRC patients were included. Overall, the pooled results showed that low expression of claudin-1 was associated with TNM III-IV stage of CRC patients (OR: 1.714, 95%CI: 1.215-2.418, P = 0.002). Low expression of claudin-1 was also associated with a poor survival in CRC patients (one year survival rate: OR: 2.112, 95%CI: 1.028-4.339, P = 0.042; three years survival rate: OR: 1.501, 95%CI: 1.030-2.186, P = 0.035; five years survival rate: OR: 1.794, 95%CI: 1.139-2.439, P = 0.000). Whereas, low expression of claudin-1 is not associated with gender (OR: 1.259, 95%CI: 0.957-1.657, P = 0.100), tumors' differentiation (OR: 1.317, 95%CI: 0.916-1.892, P = 0.137), depth of invasion (OR: 1.016, 95 %CI: 0.701-1.472, P = 0.935) and lymph node metastasis group (OR: 1.286, 95% CI: 0.982-1.684, P = 0.06) of CRC.ConclusionsLow expression of claudin-1 is associated with TNM III-IV stage and poor prognosis of CRC patients. Low expression of claudin-1 is not associated with gender, tumors' differentiation depth of invasion and lymph node involvement of CRC patients.