Prognostic and clinical significance of syndecan-1 in colorectal cancer: a meta-analysis

BACKGROUND: Syndecan-1 plays a vital role in the suppression, transformation, and migration of several cancer types, including colorectal cancer (CRC). However, the prognostic and clinical significance of syndecan-1 in CRC remains conflicting. Therefore, we performed a meta-analysis to clarify this relationship. METHODS: A comprehensive literature search for relevant studies published up to December 2014 was performed using PubMed, EMBASE, and Ovid library database. The odds ratio (OR) and pooled hazard ratio (HR) with their 95 % confidence intervals (CI) were used to estimate the effects. RESULTS: Ten studies with 888 CRC patients were selected for evaluation. The results showed that syndecan-1 expression was lower in CRC tissue than in normal colorectal tissue (OR = 0.02, 95 % CI = 0.00–0.09), and lower in the advanced stage than in the early stage (OR = 2.24, 95 % CI = 1.14 − 4.42). Additionally, syndecan-1 expression was higher in well and moderately differentiated CRC than in poorly differentiated CRC (OR = 2.91, 95 % CI = 1.21–6.98); no significant difference was found in patients with or without lymph node metastasis (OR = 0.91, 95 % CI = 0.34–2.43) and distant metastasis (OR = 0.89, 95 % CI = 0.19-4.21). The pooled results showed that syndecan-1 expression was not associated with survival in CRC patients (HR = 0.93, 95 % CI = 0.86–1.01). CONCLUSION: This meta-analysis indicated that loss of syndecan-1 expression is associated with CRC development, histological differentiation, and clinical stage, but not with lymph node metastasis and distant metastasis. In addition, these findings fail to support the prognostic significance of syndecan-1 in CRC.