Construction of Resistant Cancer Cell Lines

TFK1, RBE, SSP25, HuCCT1, HuCCA1, HuH28, KKU213A, KKU213B, KKU213C, KKU068, KKU131, KKU138, KKU055, KKU100, and YSCCC cell lines were obtained from the Japanese Collection of Research Bioresources (JCRB; Osaka, Japan). TFK1, RBE, SSP25, and YSCCC cells were maintained in Roswell Park Memorial Institute 1640 medium (RPMI 1640) (Gibco; Thermo Fisher Scientific, Waltham, MA, USA). HuCCA1 and KKU100 cells were maintained in Ham’s F-12 medium (Gibco; Thermo Fisher Scientific). HuCCT1, HuH28, KKU213A, KKU213B, KKU213C, KKU068, KKU131, KKU138, and KKU055 cells were maintained in Dulbecco’s Modified Eagle’s Medium (DMEM) (Gibco; Thermo Fisher Scientific). All cell lines were routinely tested for mycoplasma. For the construction of resistant cells, parental cells (KKU213C, TFK1, KKU068, and SSP25) were seeded in 12-well plates at 5 x 10⁴ cells/well in 1 milliliter (ml) of growth medium. Cells were treated with GEM/CIS using a stepwise dose-induction protocol (16 (link)).