Stanniocalcin‑1 promotes cell proliferation, chemoresistance and metastasis in hypoxic gastric cancer cells via Bcl‑2

Abstract

Gastric cancer (GC) is one of the most lethal diseases worldwide, but the mechanism of GC development remains elusive. In the present study, the roles of stanniocalcin-1 (STC1) in GC were investigated. It was demonstrated that overexpression of STC1 mRNA and protein were associated with poor survival of patients with GC. The expression of STC1 was enhanced in hypoxic GC cells and overexpression of STC1 facilitated cell proliferation in hypoxia but not in normoxia. Furthermore, STC1 promoted chemoresistance, migration and invasion in hypoxia. Upregulating the expression of STC1 enhanced the expression of B cell lymphoma (Bcl)-2, neural-cadherin and matrix metalloproteinase-2, whereas it reduced the levels of cytochrome c, cleaved-caspase-9, cleaved-caspase-3 and epithelial-cadherin. However, down-regulation of STC1 altered the expression of these proteins in the opposite direction. Furthermore, disturbing the expression of Bcl-2 partly reversed the changes to these proteins and also the pro-proliferation, anti-apoptosis and pro-invasion potential of STC1. In vivo experiments indicated that enhanced expression of STC1 promoted tumor growth and metastasis in mice. Collectively, the results indicated that STC1 may serve an oncogenic role in hypoxic GC via dysregulating Bcl-2, indicating that STC1 may be a potential therapeutic target in the treatment of GC.