Hpasmcs

HPASMCs were purchased from American Type Culture Collection (MD, USA) and grown in Dulbecco’s Modified Eagle’s Medium-F12 containing 10% fetal bovine serum. Cigarette smoke extract (CSE) obtained from Research Cigarettes (Code 3R4F, University of Kentucky, USA) was acquired as described elsewhere [35 (link)]. DNMT1 small interfering RNA (siRNA; 50 nM) was transfected into HPASMCs using Lipofectamine 2000 (Invitrogen, USA) for silencing DNMT1. DNMT1 siRNA target sequences were as follows: the first 5′-GCACCUCAUUUGCCGAAUATT-3′; the second 5′- GGGACUGUGUCUCUGUUAUTT-3′. DNMT1 overexpression pcDNA3.1 plasmid vector was also transfected into HPASMCs using Lipofectamine 2000 (Vigene Biosciences, China). The RASEF overexpression adenovirus vector (Ad.RASEF; Vigene Biosciences, China) was also transfected into HPASMCs (MOI 250).