Genomic and Proteomic Characterization of Canine Mast Cell Tumors and Development of Prognostic Biomarkers for Surgical Outcome Prediction in South East Nigeria

Canine mast cell tumors exhibit marked biological heterogeneity ranging from indolent cutaneous lesions to highly aggressive metastatic malignancies, and the identification of reliable molecular biomarkers for surgical outcome prediction remains an unmet clinical need in Nigerian veterinary oncology. This doctoral study undertakes genomic and proteomic characterization of mast cell tumor tissue samples from dogs undergoing surgical excision at teaching hospitals in Enugu, Imo, Anambra, Abia, and Ebonyi States, South East Nigeria, between 2021 and 2024. Archived and freshly excised tumor specimens from 88 surgically managed dogs were subjected to targeted next-generation gene panel sequencing and label-free quantitative proteomics. Clinical follow-up data on local recurrence, metastatic progression, and disease-free survival were prospectively collected for 18 months post-excision. KIT exon 11 mutations were identified in 31% of analyzed tumors and correlated significantly with high histopathological grade and shorter disease-free survival. Proteomic analysis identified four overexpressed proteins in high-grade tumors including two previously unreported in West African canine mast cell tumor literature. A multivariate prognostic model incorporating KIT mutation status, histological grade, and two proteomic markers predicted disease-free survival with a concordance index of 0.79. These original genomic and proteomic findings constitute a significant theoretical and translational contribution to canine oncology, providing the basis for clinically deployable surgical outcome biomarkers specific to the Nigerian mast cell tumor patient population. Keywords: mast cell tumor, genomics, proteomics, prognostic biomarker, canine oncology.