Novel role of granulocyte-macrophage colony-stimulating factor: antitumor effects through inhibition of epithelial-to-mesenchymal transition in esophageal cancer

PURPOSE: Recent studies demonstrate the possible antitumor effects of granulocyte-macrophage colony-stimulating factor (GM-CSF); however, the exact mechanism is still unclear. The aim of our study was to analyze the effects of GM-CSF on multiple biological functions of human esophageal cancer (EC) cell lines and to explore the potential mechanism of its antitumor effects. MATERIALS AND METHODS: Eca109/9706 human EC cells were examined. Cell proliferation, apoptosis, and migration were analyzed using cell proliferation assay, flow cytometry, and transwell assay, respectively. The expression of signaling molecules were examined by reverse transcription polymerase chain reaction and Western blot. RESULTS: Our results provide experimental evidence that GM-CSF inhibits growth and migration, as well as induction of apoptosis in EC cells. In addition, EC cells stimulated with GM-CSF were more likely to have suppressed epithelial-to-mesenchymal transition (EMT), accompanied by increased E-cadherin and decreased vimentin expression. CONCLUSION: Our data demonstrate that GM-CSF inhibits cancer cell proliferation and migration, as well as induction of apoptosis. Moreover, our findings indicate that GM-CSF may regulate EMT through JAK2-PRMT5 signaling, and thereby exhibit its antitumor effects on EC cells.