Laser capture microdissection-based transcriptomic analysis of neoplastic mast cells reveals novel molecular alterations across canine mast cell tumor grades

In this study, neoplastic mast cells (MCs) were isolated from formalin-fixed paraffin-embedded (FFPE) canine MCT biopsies using laser capture microdissection (LCM), followed by RNA sequencing of these cells. In this way, MC-specific mechanisms were investigated in high- versus low-grade canine MCTs.

To this end, 32 canine cutaneous MCTs were analysed, of which 18 were graded as low- and 14 as high-grade tumors based on histopathology. A total of 74 differentially expressed genes were identified including MOB3B, EXOC6B, BAIAP2, and TRMO, which have established associations with several human cancers. Gene Set Enrichment Analysis revealed significant enrichment of tumorigenic pathways, including KIT signalling, Ras signalling, ubiquitin-mediated proteolysis, and neurotrophin signalling in high-grade MCTs.