First passage normal hok

First passage normal HOK, oral keratinocyte medium (OKM), oral keratinocyte growth supplement (OKGS) and penicillin/streptomycin solution (P/S) were purchased from ScienCell Research Laboratories (San Diego, CA). Nunclon Δ-surface multidishes, plastic coverslips, pipettes and sealing tapes were purchased from VWR International (West Chester, PA). The calcein-acetoxymethyl ester (CAM) and the minimum essential medium (MEM) were obtained from Invitrogen (Carlsbad, CA). Phosphate-buffered saline (PBS), 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES), bovine serum albumin (BSA), sodium bicarbonate, propidium iodide (PI) solution, Tween 20 and 4',6-diamidino-2-phenylindole (DAPI) were all from Sigma-Aldrich (St. Louis, MO). Rabbit polyclonal anti-cleaved caspase-3 antibody (Asp 175) was supplied by Cell Signaling Technology (Danvers, MA), while mouse monoclonal anti-proliferating cell nuclear antigen antibody (PCNA; clone PC10) was purchased from DAKO (Glostrup, Denmark). Rat monoclonal anti-BCRP/ABCG2 antibody (BXP-53), mouse monoclonal anti-cytokeratin 18 (CK18) antibody, rabbit polyclonal anti-C/EBPδ antibody, mouse monoclonal anti-Bmi1 antibody (clone 1.T.21), FITC-conjugated goat anti-mouse IgG and Cy3-conjugated goat anti-rabbit IgG were purchased from Abcam (Cambridge, UK) (Table 1).

First passage normal HOK, oral keratinocyte medium (OKM), oral keratinocyte growth supplement (OKGS), and penicillin/streptomycin solution (P/S) were purchased from ScienCell Research Laboratories (San Diego, Carlsbad, CA, USA). Nunclon Δ-Cell culture flasks and pipettes were purchased from VWR International (West Chester, PA, USA). The Minimum Essential Medium (MEM) was obtained from Invitrogen (Carlsbad, CA, USA). Phosphate-buffered saline (PBS), 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES), and sodium bicarbonate were all purchased from Sigma-Aldrich (St. Louis, MO). RNeasy Plus Mini Kit and the QIAzol Lysis Reagent were provided by Qiagen (Hilden, Germany).