The Comparative Oncology of Canine Malignant Melanoma in Targeted Therapy: A Systematic Review of

Canine malignant melanoma (CMM) is highly aggressive and mostly located in the oral cavity. CMM is the predominant type of canine oral malignancy and shows striking homologies with human mucosal melanoma. In comparative oncology, canine oral melanomas (COMs), as spontaneous tumor models, have the potential to acquire a unique value as a translational model of rare human melanoma subtypes. This review aims to provide a comprehensive summary of targeted therapies for canine malignant melanoma and to enrich the field of comparative oncology. Following the PRISMA guidelines, a comprehensive literature search was conducted across databases for studies from 1976 to April 2024. Studies were selected based on their relevance to targeted treatments. A total of 30 studies met the inclusion criteria. Based on the treatment approaches, the studies were further categorized into immunotherapies, small molecule signaling inhibitors, indirect kinase inhibitors, and other alternative strategies. Some treatments have been shown to result in stable disease or partial response, accounting for 29% (monoclonal antibody) and 76.5% (micro-RNA therapies) in clinical trials. Moreover, in vitro experiments of small molecule inhibitors, including cell signaling inhibitors and indirect kinase inhibitors, have shown the potential to be an effective treatment option for the development of therapeutic strategies in canine malignant melanoma. The observed response in in vitro experiments of CMM (particularly the oral and certain cutaneous subtypes) to drugs used in the treatment of human melanoma underlines the resemblance to human melanoma, therefore supporting the notion that CMM may be a valuable model for understanding rare human melanoma subtypes and exploring potential therapeutic avenues in preclinical trials. Finally, this literature review serves as a valuable resource for the development of therapeutic strategies for CMM and highlights the potential for translating these findings to human cancer treatment.