Clinical significance and prognostic value of SOX7 expression in liver and pancreatic carcinoma

Sex determining region Y-box 7 (SOX7) is known to function as a tumor suppressor in a number of types of cancer; however, its role in liver and pancreatic carcinoma remains unclear. The present study investigated the association between SOX7 expression and the clinical pathology of these carcinomas, in particular if SOX7 expression may be used to predict recurrence and patient prognosis following radical resection of liver and pancreatic carcinoma. SOX7 expression in human liver and pancreatic carcinoma was detected by immunohistochemical analyses and validated using mRNA data from a high-throughput sequencing dataset from The Cancer Genome Atlas (TCGA). SOX7 expression was significantly downregulated in liver and pancreatic carcinoma relative to the adjacent benign tissues [immunoreactivity scores: Liver carcinoma (3.53±1.57) vs. benign (7.00±0.00), P<0.001; and pancreatic carcinoma (2.39±1.88) vs. benign (4.80±0.45), P=0.005]. In addition, downregulation of SOX7 was significantly associated with advanced stage liver carcinoma, and the primary pathological tumor stage and regional lymph node stages. These findings were further validated in the TCGA dataset. However, SOX7 down regulation was closely associated with the only pathological grade in pancreatic patients. Kaplan-Meier analyses revealed significant differences in overall and disease-free survival between patients with high and low levels of SOX7 expression. In addition, a multivariate analysis with Cox regression indicated that SOX7 may be an independent predictor of disease-free survival. The results indicate that SOX7 may inhibit the progression of liver carcinoma and that SOX7 downregulation may accurately predict poor prognosis in liver carcinoma patients.