Mkn45

GC tissue samples and paired normal tissue samples were obtained from 47 patients who underwent surgery between March 2017 and March 2018 at Chengyang People's Hospital (Qingdao, Shandong, China) with written informed consent. All samples were frozen in liquid nitrogen and stored at −80°C until use. The present study was approved by the Ethics Committee of Chengyang People's Hospital. GC tissues were fixed in 4% buffered paraformaldehyde for 24 h at 4°C, embedded in paraffin and then sectioned to 5 µm. These sections were stained with hematoxylin for 15 min and eosin for 5 min at 25°C. Samples were examined under a light microscope at a magnification of ×400. The human gastric epithelial mucosa cell line GES-1 and GC cell lines HGC-27, AGS, MKN45 and NCI-N87 were purchased from Nanjing Keygen Biotech Co., Ltd. HGC-27, AGS, MKN45 and NCI-N87 cells were maintained in RPMI-1640 with 10% foetal bovine serum (FBS), 100 U/ml penicillin and 100 µg/ml streptomycin (HyClone; GE Healthcare Life Sciences). GES-1 cells were cultured in Dulbecco's modified Eagle's medium (DMEM) with FBS, 100 U/ml penicillin and 100 µg/ml streptomycin (HyClone; GE Healthcare Life Sciences). All cells were cultured in a humidified chamber with 5% CO₂ at 37°C.