Nci n87

GC cell lines (KATO-III, SGC-7901, BGC-823, HGC-27, AGS, NCI-N87, SNU-1 and SNU-16) and normal gastric epithelial cells (GES cells) were bought from the Shanghai Institute of Biochemistry and Cell Biology (Shanghai, China). All the cells were cultured at 37°C in a humidified atmosphere containing 5% of CO2 in Dulbecco’s Modified Eagle’s Medium (DMEM) supplemented with 10% of fetal bovine serum (FBS),100 U/ml penicillin, and 100 µg/ml streptomycin (all from Gibco, Invitrogen Life Technologies, Carlsbad, CA, USA).

The gastric cancer cell lines (HGC-27, NCI-N87, SNU-5 and KATO-III) were purchased from the Shanghai Institute of Biochemistry and Cell Biology (Shanghai, China), along with human gastric mucosal epithelial cell line GES-1 which was used as a control. Cell lines were grown in RPMI 1640 medium (Invitrogen, USA) containing 10% fetal bovine serum (FBS) (Invitrogen, USA), in a 5% CO₂ atmosphere at 37°C. Transfection of the cells was performed using LipofectamineTM 3000 (ThermoFisher Scientific, USA) by following the manufacturer’s instructions. The sequence used in transfection, including the ASMTL-AS1-expressed pcDNA3.1(+) vectors (ov-ASMTL-AS1), empty pcDNA3.1(+) vector (ov-NC), miR-1270 mimic, and mimic negative control, was from Genebio (Shanghai, China). The effect was examined after 48 hours of transfection by quantitative reverse transcription-polymerase chain reaction (RT-qPCR) assay using the extracted RNA.