KIT and gastrointestinal stromal tumor: However, so far, ferroptosis has not been investigated in imatinib-sensitive GIST882 (KIT exon 13 mutation) cells, or in imatinib-resistant GIST48 cells (KIT primary exon 11 and resistant exon 17 mutations), which originate from a GIST patient who had progressed under imatinib treatment.