Culturing with anti-human KITLG neutralizing antibody [37] for 4 days inhibited the proliferation of GIST-T1 cells by ~40% (IC50: ~9 ng/mL) and GIST-T1-5R cells by ~34% (IC50: ~26 ng/mL) (Figure 1B), whereas the same treatment had no effect on KIT+ GIST882 and KITlow/– GIST48B cells lacking WT KIT allele or on KIT- LX-2 cells. Here, KITLG is linked to gastrointestinal stromal tumor.