There are many pieces of evidence support the effect of cancer stem cells on the initiation and progression of cancer. However, related mechanisms involved in these phenomena are far more complicated to understand. The function of different stemness factorsin cancer stem cells (CSCs) and their complex associations at different levels of cancer have been reported. Therefore, it seems that focusing on one master factor would be more helpful to complete the puzzle of singling pathways in these cells. Octamer-binding transcription factor 4 (OCT4) also known as POU domain, class 5, transcription factor 1(POU5F1), one of these key pluripotency factors, has important roles in both embryogenesis and tumorigenesis. In this review, we gathered information about the association of different markers with OCT4 expression in three types of gastrointestinal cancers including esophageal, gastric and colorectal cancers. OCT4 through different signaling pathways has an impact on different processes of gastrointestinal cancers such as proliferation, invasion, and metastasis. Based on the literature, OCT4 has great effects on cancer progression at different stages, therefore we suggested it has potential implications in therapeutic options.
Keywords: Colorectal cancer; Esophageal neoplasms; Stomach neoplasms.