Abstract / Summary
Abstract MicroRNA biomarkers offer promising avenues for advancing cancer diagnosis and therapeutic strategies. Several mature human miRNAs, including miRNA-145, miRNA-451, and miRNA-199, are reported biomarkers in human breast cancer (HBC), enabling comparative oncology studies. Canine mammary tumors (CMTs), recognized as valuable models for HBC, were investigated in this study to evaluate the diagnostic potential of these miRNAs, along with a chemically induced rat mammary tumor model. Serum samples from dogs with CMT showed significant upregulation of miRNA-145 and miRNA-199, while miRNA-451 was downregulated compared to non-tumorous controls. Among these, miRNA-145 exhibited the highest sensitivity (46.6%), followed by miRNA-199 (33.3%). A three-miRNA panel detected 63.3% of CMT cases with 95% specificity. Tissue analysis confirmed upregulation of miRNA-145 in most tumor samples. Furthermore, longitudinal serum analysis in rats during N-methyl-N-nitrosourea (MNU)-induced mammary tumor progression revealed dynamic changes in miRNA expression. This temporal profiling highlighted the potential of miRNA-145 and miRNA-199 as biomarkers not only for early cancer detection but also for treatment monitoring and recurrence tracking. To our knowledge, this is the first study to evaluate the diagnostic potential of the miRNA-145, miRNA-451, and miRNA-199 panel in CMTs. Larger canine cohorts are needed to validate their clinical utility in diagnosis, disease monitoring, and recurrence prediction.