KIT and gastrointestinal stromal tumor: To further investigate the in vivo effects of CAFs on GIST growth, we subcutaneously injected T1 (n = 7), T1 with CAFs (n = 7), GIST882 (KIT exon 13 mutant; n = 5) [30], and GIST882 with CAFs (n = 5) into nude mice.