Mkn74

AGS, HGC-27, and GES-1 cell lines were obtained from American Type Culture Collection (Manassas, Virginia, USA), MKN-45, MKN-74, and MKN-28 were from JCRB Cell Bank (National Institute of Hygienic Sciences,Tokyo), BGC-823 and SGC-7901 cell lines were purchased from Cell Bank of the Shanghai Institute for Biological Sciences (Chinese Academy of Sciences, Shanghai, China), and MGC-803 was from National Infrastructure of Cell Line Resource (Beijing, China). All cell lines were genotyped for identity by Shanghai Biowing Applied Biotechnology Co., Ltd. and tested routinely for Mycoplasma contamination. HGC-27, MKN-28, MKN-74, SGC-7901, MGC-803, and BGC-823 cells were maintained in Dulbecco’s Modified Eagle Medium (Hyclone) while GES, AGS, and MKN-45 were cultured in RPMI 1640 medium (Hyclone). All medium were supplemented with 10% fetal bovine serum (Hyclone) and penicillin–streptomycin (penicillin 100 U/ml and streptomycin 0.1 mg/ml, Beyotime). All cell lines were cultured in a 37 °C incubator supplemented with humidified and 5% CO₂ atmosphere.

Human stomach adenocarcinoma cell line MKN74, lacking endogenous CD44 expression [37 (link)], was purchased from the Japanese Collection of Research Bioresources (JCRB) Cell Bank, while the established isogenic human GC cell line expressing the CD44v6 isoform [15 (link)] (henceforth termed as CD44v6 cells) was kindly provided by Dr. C. Oliveira, a co-author in this study. MKN74 cells (passages 49–62) and CD44v6 cells (passages 7–20) were routinely cultured in Dulbecco’s modified Eagle medium (DMEM, Gibco, Paisley, UK) containing 10% (v/v) fetal bovine serum (FBS, BioWest, Nuaillé, France) and 1% (v/v) penicillin/streptomycin (Pen/Strep, BioWest, Nuaillé, France). Additionally, the latter cells were supplemented with 1% (v/v) geneticin (Gibco, Paisley, UK). Human adipose stromal cells (ASCs, Lonza, Walkersville, MD, USA) were cultured in their corresponding growth media (ADSC-GM, Lonza, Walkersville, MD, USA) and utilized up to passage 6. Cell cultures were maintained at 37 °C under a 5% CO₂ humidified atmosphere.

The GC cell lines GCIY, IM95, MKN1, MKN7, MKN45, MKN74, NUGC2, NUGC3, NUGC4, OCUM-1, and SC-6-JCK were obtained from the Japanese Collection of Research Bioresources Cell Bank (JCRB, Osaka, Japan). AGS, KATOIII, and N87 GC cell lines and a nontumorigenic epithelial cell line (FHs74) were acquired from the American Type Culture Collection (Manassas, VA, USA). Three hundred pairs of surgically resected GC and adjacent noncancerous tissues were obtained from patients who underwent gastrectomy. A freely available integrated dataset (n = 1065 GC patients) was accessed at http://kmplot.com/analysis/ [13 (link)].

Human GC cell lines MKN74 and MKN45 (intestinal- and diffuse-type GC, respectively; Japanese Collection of Research Bioresources Cell Bank) were seeded on 3D CoSeedis matrices (1 × 10⁵ cells/mL; abc biopply, Solothurn, Switzerland), as previously described [33 (link)], and cultured in RPMI 1640 medium (Thermo Fisher Scientific) supplemented with 10% fetal bovine serum (FBS; Biowest, Nuaillé, France) and 1% penicillin-streptomycin (PS; Thermo Fisher Scientific), at 37 °C in 5% CO₂ humidified atmosphere, for 7 days to allow spheroid formation before co-culture with T cells.

The human gastric cancer cell lines MKN1 (RRID, CVCL_1415), MKN74 (CVCL_2791), MKN45 (CVCL_0434), and NUGC3 (CVCL_1612), as well as HeLa cervical carcinoma cells (CVCL_0030), were obtained from the JCRB cell bank. The human gastric cancer cell lines SNU1 (CVCL_0099), Hs746T (CVCL_0333), and NCI‐N87 (CVCL_1603) were from American Type Culture Collection and SNU216 (CVCL_3946) was from the Korean Cell Line Bank. The cells were maintained under a humidified atmosphere of 5% CO₂ at 37°C in RPMI 1640 medium (Sigma‐Aldrich) supplemented with 10% heat‐inactivated fetal bovine serum (FBS) (Biowest) and 1% penicillin‐streptomycin‐amphotericin B (Wako). Cells were tested for mycoplasma contamination using MycoAlert (LT07, Lonza) and were confirmed negative. Eribulin was obtained from Eisai Co. Ltd and Oxaliplatin from Yakult. MORAb‐202 and farletuzumab were provided by Eisai Co. Ltd. MG132 was obtained from Funakoshi.

GC cell lines (MKN74, AGS, MKN7) were used in this study. AGS were obtained from ATCC (American Type Culture Collection, Manassas, VA). MKN74 was obtained from JCRB (Japanese Collection of Research Bioresources Cell Bank, Japan). MKN7 was obtained from BNCC (BeNa Culture Collection, China). AGS and MKN74 were obtained between 2014 and 2015 and MKN7 were obtained 2023. These cells authentication was confirmed by short tandem repeat profiling. Cells were cultured and maintained in Dulbecco’s Modified Eagle’s Medium (DMEM, Gibco BRL) supplemented with 10% fetal bovine serum (FBS, Gibco BRL) and 1% antibiotics according to the ATCC protocols. Cells were maintained at a 37 °C incubator with 5% CO2. Routine Mycoplasma testing was performed by PCR. Cells were grown for no more than 25 passages in total for any experiment.