The octamer-binding transcription factor 4 (OCT4) can promote cancer proliferation and metastasis. Esophageal carcinoma (ECC) harbors different quantities of OCT4-positive cancer cells. These cells are highly malignant and prone to metastasis; however, the mechanism remains unknown. In this study, we found that OCT4 enhances vascular endothelial growth factor C (VEGF-C) promoter activity to promote VEGF-C expression and activates VEGF receptor 3 (VEGFR-3) in ECC cells, thereby inducing cancer cell epithelial-mesenchymal transition (EMT). Studies using xenograft models showed that OCT4 promoted xenograft growth and intraperitoneal implantation metastasis of ECC cells. Downregulation of OCT4 expression could inhibit cancer metastasis. OCT4- and VEGF-C-positive ECC presented more malignant biological behaviors and the corresponding patients exhibited a poor prognosis. The study confirmed that the OCT4/VEGF-C/VEGFR-3/EMT signaling plays a role in the progression of ECC. Understanding of how OCT4 regulates EMT and how ECC metastasis occurs will provide useful targets for the biological treatment of ECC.
Keywords: epithelial-mesenchymal transition; esophageal carcinoma; metastasis; octamer-binding transcription factor 4; signaling.