Abstract 1219: Spatial multi-omic profiling to capture functional signatures in HER2-heterogeneous FFPE breast cancer tissue.

Key Points

• This research aims to characterize the spatial heterogeneity of HER2 expression in breast cancer by profiling its molecular signatures in FFPE tissue samples.
• Applied spatial multi-omic profiling on FFPE breast cancer tissues using SLACS for regional isolation.
• Analyzed the proteome using LC-MS and the transcriptome through RNA sequencing on adjacent tissue areas.
• Compared HER2-high and HER2-low regions to identify differentially expressed proteins (DEPs).
• Identified a total of 6,116 proteins and 1,188 DEPs between HER2-high and HER2-low regions.
• Proteins in HER2-high areas were linked to pathways involved in protein synthesis and metabolism, while HER2-low areas were enriched for mitochondrial function and cellular differentiation.
• Pathway analysis indicated that HER2-related signaling is more activated in HER2-high regions, highlighting potential post-transcriptional regulation.