The impact of osteopontin on prognosis and clinicopathology of colorectal cancer patients: a systematic meta-analysis

Colorectal cancer (CRC) is one of the most frequent malignant neoplasms worldwide. Up to now, no biomarker has been used to predict the prognosis and surveillance of patients with CRC. Recently, the association between osteopontin (OPN) overexpression and the prognosis of CRC was investigated widely, but the results were inconsistent. Therefore, the aim of present meta-analysis was to assess the prognostic effect of osteopontin in patients with CRC. PubMed, EMBASE, Web of Science, Scopus and Chinese Medical Database were systematically searched. A total of 15 studies containing 1698 patients were included in our meta-analysis. The pooled data of studies showed that high OPN expression was significantly associated with high tumor grades (OR = 2.24, 95% CI 1.55-3.23), lymph node metastasis (OR = 2.36, 95% CI 1.71-3.26) and tumor distant metastasis (OR = 2.38, 95% CI 1.01-5.60). Moreover, high OPN expression was significantly associated with the 2-year (HR 1.97, 95% CI 1.30-3.00), 3-year (HR 1.82, 95% CI 1.24-2.68), 5 year (HR 1.53, 95% CI 1.28-1.82) survival rates and overall survival (OS, HR 1.70, 95% CI 1.12-2.60), respectively. These results indicated that OPN could serve as a prognostic biomarker and as a potential therapeutic target for CRC.