[The effect of PM(2.5) on oncogene expression in HBE cells]

Objective: To study the effect of particulate matter 2.5 (PM(2.5)) on oncogene expression in human bronchial epithelial (HBE) cells. Methods: HBE cells were selected as the study subjects, and PM(2.5) treatment group (10 μg/ml and 50 μg/ml) , negative control group and positive control group (10 μmol/L Cr(6+)) were set. CCK8 assay was used to test the IC(50) value of PM(2.5). HBE cells were treated with PM(2.5) for 24 h at 10 μg/ml and 50 μg/ml, additionally, cells were treated with blank as negative control, 10 μmol/L Cr(6+) as a positive control for 24 h. After the treatment, mRNA expression of oncogenes including c-myc, c-fos, k-ras and p53 were detected by fluorescent quantitative RT-PCR, the protein expression of oncogenes were detected with western blot. Results: The IC(50) value of PM(2.5) in HBE cells is 70.12 μg/ml. The qRT-PCR data showed that compared with the control group, the expression level of c-myc gene increased by respectively 500.1%、780.7%、305.3% after exposure to 10、50 μg/ml PM(2.5) and positive control group; c-fos gene increased respectively 34.0%、76.7%、131.3% after exposure to 10、50 μg/ml PM(2.5) and positive control group; k-ras gene increased respectively 50.3%、107.0%、49.7% after exposure to 10、50 μg/ml PM(2.5) and positive control group; p53 gene decreased by 28.3%、28.7%、59.7% after exposure to 10、50 μg/ml PM(2.5) and positive control group. The western blot results showed that compared with the control group, c-myc protein increased respectively 29.7%、77.3% after exposure to 50 μg/ml PM(2.5) and positive control group; c-fos protein increased respectively 200.3%、137.0% after exposure to 50 μg/ml PM(2.5) and positive control group; k-ras protein increased respectively 106.3%、130.3%、116.7% after exposure to 10、50 μg/ml PM(2.5) and positive control group; p53 protein decreased by 43.7%、53.3%、52.1% after exposure to 10、50 μg/ml PM(2.5) and positive control group. Conclusion: PM(2.5) could promote the expression of oncogenes in HBE cells, the carcinogenicity of haze might be related to promotion of oncogenes expression induced by PM(2.5).