Expression data from SDH-disabled GIST

Pediatric GIST commonly harbors a disabled succinate dehydrogenase complex (SDH), which yields tumors with highly conserved genomes but characteristic epigenomic signatures. Mysteriously, nearly half of such SDH-deficient GIST, including tumors from Carney Triad patients, lack identifiable mutations in SDH component genes and genes required for complex assembly (SDHA, SDHB, SDHC, SDHD, SDHAF, termed SDHx). Genomic sequencing coupled with DNA methylation and transcriptional profiling have exposed SDHC promoter-specific CpG island epimutation and concomitant gene silencing in the majority of SDHx-WT GIST. We performed whole genome expression profiling on 20 FFPE dSDH GIST tumors using Affymetrix U133P2 arrays which contain >54K gene target probesets. Included here were data from 7 SDHx-w.t. and 13 SDHx mutants that passed array QC.