Upregulation of SYF2 in esophageal squamous cell carcinoma promotes tumor cell proliferation and predicts poor prognosis.

SYF2, also known as CCNDBP1-interactor or p29, is reported in pre-mRNA splicing and cell cycle progression. However, the role of SYF2 in esophageal squamous cell carcinoma (ESCC) development remains elusive. In the present study, Western blot and immunohistochemistry assays demonstrated that SYF2 was overexpressed in ESCC tumor tissues and cell lines. In addition, immunohistochemistry analysis revealed that SYF2 expression was positively correlated with tumor grade and predicted poor prognosis of ESCC. In vitro studies using serum starvation-refeeding experiment and SYF2-siRNA transfection assay demonstrated that SYF2 expression promoted proliferation of ESCC cells, while SYF2 knockdown led to decreased cell growth rate and colony formation resulted from growth arrest of cell cycle at G0/G1 phase. Furthermore, our results indicated that SYF2 can down-regulate the sensitivity of ESCC cells for cisplatin. Our findings for the first time supported that SYF2 might play an important role in the regulation of ESCC proliferation and would provide a novel therapeutic strategy against human ESCC.