Upregulation and secretion of macrophage inhibitory cytokine-1 (MIC-1) in gastric cancers

Abstract

Background: Macrophage inhibitory cytokine-1 (MIC-1), a distant member of the transforming growth factor (TGF)-β superfamily, has been reported to be upregulated and secreted from several cancers. We examined MIC-1 expression and secretion in gastric cancers. Methods: MIC-1 mRNA and protein levels in cancer tissues and cell lines were analyzed by RT-PCR and Western blot. MIC-1 expression in cancer tissues and its secretion in serum were analyzed using immunohistochemistry and ELISA. Results: MIC-1 was significantly upregulated in gastric cancer tissues and cell lines. MIC-1 was secreted from gastric SNU620 cells and its levels in the serum of cancer patients were 10-fold higher than those of healthy controls. In addition, the staining of MIC-1 expression was strongly increased in metastatic gastric cancers. Conclusions: MIC-1 was obviously overexpressed in gastric cancers and MIC-1 secretion into blood may be useful for the prediction of gastric cancer progression.