Mir146a 5p mimic and inhibitor

A human gastric mucosal epithelial cell line (GES-1) was purchased from the Xiangya Experiment Center (Changsha, China), Human GC cells (AGS, BGC-823, MGC-803, and SGC-7901) and HEK293 cell lines were purchased from the Institute of Biochemistry and Cell Biology of the Chinese Academy of Sciences (Beijing, China). AGS, BGC-823, MGC-803, and SGC-7901 cells were cultured in RPMI 1640 medium (Gibco, California, USA), GES-1 and HEK293 cells were cultured in DMEM (Gibco) with 10% fetal bovine serum (BD Bioscience, San Jose, CA, USA or ExCell Bio, Shanghai, China), at 37 °C in a humidified incubator with 5% CO₂. Culture flasks were purchased from JET BIOFIL (Guangzhou, China). Cells were treated with 2 mg/ml actinomycin D (Meilune, Dalian, China) for 4, 8, 12, and 24 h, with dimethylsulfoxide as a negative control. LSECtin or STAT1 overexpression plasmids, short interfering RNAs (siRNAs) targeting STAT1 or circFBXL4, and miR146a-5p mimic and inhibitor were purchased from GenePharma (Shanghai, China) and then were transfected with Lipofectamine 2000 (Invitrogen, Carlsbad, CA). The sequences and NCBI identifiers are available as Additional files 1 and 2. Cells were treated with the STAT1 activation inhibitor fludarabine (5 µM, 24 h) (MedChemExpress, Dalian, China), with dimethylsulfoxide as a negative control.

The lentivirus packaging and transduction were performed by Shanghai Genechem Co., Ltd. The lentivirus‐mediated silencing vectors containing XIST shRNA were cloned into a pLKD‐CMV‐G&PR‐U6‐shRNA vector. After the transfection in PMVECs with 5 mg/mL polybrene, puromycin (2 mg/mL) was added to select the infected cells. miR‐146a‐5p mimic and inhibitor were purchased from GenePharma. The indicated shRNA sequences are listed in Supplementary Table S1.