This report described the differentiation induction of canine oral mucosal melanoma (OMM) cells by resveratrol. Exposure of canine OMM cells to resveratrol (maximum dose: 50 μM and treatment period: 72 hr) induced differentiating features like melanocytes, and enhanced chemosensitivity against cisplatin, but alone had no influence on cell viability. Additionally, resveratrol significantly enhanced mRNA expression of key melanoma differentiation markers such as microphthalmia-associated transcription factor (MITF). Of several inhibitors against mitogen-activated protein kinase subtypes, only the c-Jun N-terminal kinase (JNK) inhibitor, SP600125, induced melanocyte-like morphological change and enhanced MITF mRNA expression. Furthermore, resveratrol also suppressed JNK activation in OMM cells by approximately 33%. Overall, these findings suggest that resveratrol induces differentiation in canine OMM cells, due to the inhibition of JNK signaling.
Keywords: c-Jun N-terminal kinase; canine oral mucosal melanoma cell; cell viability; microphthalmia-associated transcription factor; resveratrol.