Bish1475

The human fibroblasts (MRC-5 cells) and mouse fibroblasts (NIH/3T3) were purchased from ATCC. The PLFs were isolated from the lung of the C57BL/6 mouse. MRC-5 cells were maintained in Minimum Essential Medium (Life Technologies/Gibco), and NIH/3T3 cells and PLFs were maintained in DMEM (Life Technologies/Gibco), which contained 10% fetal bovine serum (BISH1475, Biological Industries) and antibiotics (penicillin and streptomycin, Life Technologies/Gibco). All the cells were cultured at 37°C with 5% CO₂. Cells were treated with 5 ng/mL recombinant TGF-β1 (Peprotech) for 48 hours to induce fibroblast activation. To inhibit UHRF1 expression, fibroblasts were treated with 15 μM NSC232003 for 4 hours after TGF-β1 treatment.
UHRF1 siRNA, beclin 1 siRNA, and control siRNA were synthesized by GenePharm. UHRF1 plasmid and beclin 1 plasmid were synthesized by Genery. Cells were transfected using riboFECTCP Reagent (Ribobio) according to the manufacturer’s protocol. The UHRF1 siRNA and beclin 1 siRNA sequences are shown in Supplemental Table 1. The UHRF1 inhibitor NSC232003 was phased from MedChemExpress.

The lung epithelial cells (A549 and HBE), lung fibroblast (MRC-5), and the human monocytic cell (THP-1) were commercially obtained from the American Type Culture Collection (ATCC, Manassas, VA, USA). A549 and THP-1 cells were maintained in RPMI Medium 1640 basic (1640, Life Technologies/Gibco, Grand Island, NY, USA), the HBE cells were maintained in Dulbecco’s modified Eagle’s medium (DMEM, 1640, Life Technologies/Gibco, Grand Island, NY, USA), and the MRC-5 cells were maintained in Minimum Essential Medium (MEM, Life Technologies/Gibco, Grand Island, NY, USA). All of the culture media were containing 10% fetal bovine serum (BISH1475, Biological Industries) and antibiotics (penicillin and streptomycin, Life Technologies/Gibco, Gaithersburg, MD). Cells were cultured at 37 °C in a 5% CO₂ atmosphere.
PMA (Sigma–Aldrich) was used to treat THP-1 cells into macrophages. For all the experiments analysis, epithelial cells and THP-1 were treated with 200 or 150 μg/ml Silicon dioxide (SiO₂) (Sigma-Aldrich, St. Louis, MO, USA) together with various concentrations (2, 5, 10 mM) of metformin (Beyotime Institute of Biotechnology, Shanghai, China); MRC-5 cells were treated with 5 ng/ml TGF-β1 (Sigma-Aldrich) together with metformin.