[Establishment of CoCl2 induced hypoxic cell model of oral squamous cell carcinoma and a preliminary study on the biological behaviour change].

Abstract

To mimic oral squamous cell carcinoma (OSCC) cell hypoxia by using chemical agent CoCl2 and to investigate its biological behaviour. Oral squamous cell carcinoma cell lines HSC-3 and SCC-4 were exposed to different concentration of CoCl2. HSC-3 and SCC-4 cells were treated with 50, 100, 150, 200 µmol/L CoCl2. Expression of hypoxia inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF) and B-cell lymphoma-2 (BCL-2) were measured by real time polymerase chain reaction (PCR) and Western blotting in both mRNA and protein level. Cell proliferation, cell apoptosis and cell cycle were detected to analyze its biological behaviour. Both wound healing and Transwell assay were applied to test the ability of cell igration. The result showed that after treatment of 150 µmol/L CoCl2 for 24 h, mRNA level of HIF-1α, VEGF and Bcl-2 was increased by 6.00 ± 0.20, 5.40 ± 0.40, 5.40 ± 0.30 (SCC-4); 5.60 ± 0.30, 5.20 ± 0.60, 5.80 ± 0.40(HSC-3). OSCC cells treated with 150 µmol/L CoCl2 for 24 h were collected. Compared with control group, the growth rate of cells was significantly decreased, P value was less than 0.05 (when HSC-3, SCC-4 cultured for 2 and 3 days). The apoptosis of OSCC cells was increased when treated with 150 µmol/L CoCl2 for 24 h:HSC-3 2.25% (control group) and 5.82% (treatment group); SCC-4 2.58% (control group) and 10.27% (treatment group). The migration ablility of OSCC cells was decreased when using 150 µmol/L CoCl2 for 24 h. The migration area ratio was (31.5 ± 2.3) % (HSC-3), (29.1 ± 1.5) % (SCC-4) in control group and (18.3 ± 1.9) % (HSC-3), (13.2 ± 0.8)% (SCC-4) in treatment group (P < 0.05). The hypoxic cell model of OSCC could be induced by CoCl2. The expression level of hypoxic markers was up regulated significantly and the cells biological behaviour changed including decreased cell proliferation, increased apoptosis and decreased migration.