Characterization of GIST-T1 and Imatinib-Resistant GIST Cell Lines

The human GIST cell line, GIST-T1, provided by COSMO BIO (Tokyo, Japan), was established and has been characterized in detail by Taguchi et al. [45 (link)]. GIST-T1 has an activating mutation in KIT exon 11 and is sensitive to imatinib. The cells were originally purchased in 2014, and all experiments in this study were carried out using cells within 20 passages. Cells were authenticated through morphological examination and expression of c-kit. Imatinib-resistant GIST, GIST-IR, was established by culturing cells with increasing concentrations of imatinib (5-80 nM) for 6 months [36 (link), 37 (link)]. GIST-T1 and GIST-IR were cultured in high (4500 mg/L) glucose Dulbecco’s Modified Eagle’s Medium (Wako Pure Chemical Industries, Osaka, Japan) supplemented with 10% FBS under 5% CO₂ at 37°C. Microbial contamination test of both cell lines was conducted by an outsourced organization, ICLAS Monitoring Center (Kanagawa, Japan).