High Expression of Pregnancy Specific Beta-1-glycoprotein 1 Is Associated With Poor Gastric Cancer Prognosis.

ABSTRACT

BACKGROUND/AIM: Pregnancy specific beta-1-glycoprotein 1 (PSG1) is a member of the immunoglobulin superfamily and associated with carcinoembryonic antigens. It has been reported to be highly expressed in variety of cancers. However, the role of PSG1 in gastric cancer remains unclear. The aim of our study was to examine the clinical significance and functional role of PSG1 in gastric cancer. MATERIALS AND METHODS: We analyzed the association between PSG1 expression levels and clinicopathological features using Kaplan-Meier survival curves and publicly available microarray data. In gastric cancer cell lines, PSG1 expression levels were detected by polymerase chain reaction and western blot analysis. The functional role of PSG1 on the proliferation, migration and invasive abilities were also investigated using PSG1 siRNA or an over-expression plasmid vector through WST, transwell migration and invasion assays. RESULTS: PSG1 expression levels were higher in gastric cancer patient tissues than in normal gastric tissues. Increased expression of PSG1 was associated with poor patient prognosis. Knockdown of PSG1 inhibited cell proliferation, migration, and invasion in gastric cancer cells. In contrast, over-expression of PSG1 enhanced cell proliferation, migration, and invasion. CONCLUSION: PSG1 is up-regulated in gastric cancer and may serve as an oncogene that promotes cell proliferation, migration, and invasion. PSG1 is an independent prognostic factor for the progression of gastric cancer and may be a potential biomarker and therapeutic target for gastric cancer.