2.4 Detection of BRAF-V600E mutation in lesions and cfDNA
We performed targeted DNA sequencing to detect mutations in LCH lesions, using a customized genes panel that covers 229 genes involved in MAPK, PI3K, or Jak/STAT, Epithelial-mesenchymal transition, cell cycle, cell proliferation, apoptosis, cell adhesion/migration, and transcriptional regulation (MyGenostics Inc.). We determined BRAF-V600E levels in plasma cell-free (cf) DNA using QX200TM System Droplet Digital PCR (ddPCR) System (Bio-Rad, Hercules, CA), as described previously32.