PM2.5通过p38MAPK信号通路对HBE细胞癌基因表达的影响

目的 探讨大气细颗粒物PM_2.5通过p38MAPK信号通路对人支气管上皮（human bronchial epithelial,HBE）细胞癌基因表达的影响。方法 设立空白对照组、PM_2.5组、SB203580组、PM_2.5+SB203580组。以10 µmol/L的p38MAPK抑制剂SB203580预先处理HBE细胞30 min,接着用无血清DMEM培养基培养24 h作为SB203580组;用50 µg/mL PM_2.5染毒24 h作为PM_2.5组;用10 µmol/L的SB203580预先处理HBE细胞30 min,然后用50 µg/mL的PM_2.5染毒24 h作为PM_2.5+SB203580组;应用荧光定量PCR和Western blot检测C-MYC、C-FOS、K-RAS、P53、p38MAPK基因的mRNA和蛋白质表达水平变化。结果 与对照组比较,PM_2.5组C-MYC、C-FOS、K-RAS、p38MAPK基因表达分别升高54.0%、49.2%、96.1%、74.1%,P53基因表达下降49.1%（均P<0.01）。与PM_2.5组比较,PM_2.5+SB203580组C-MYC、C-FOS、K-RAS和p38MAPK基因表达分别下降21.4%、20.8%、39.3%和21.4%,P53基因表达升高43.1%（P<0.01或P<0.05）。Western blot结果显示,与对照组相比,PM_2.5组C-MYC、C-FOS、K-RAS、p38MAPK蛋白表达分别升高110.6%、46.7%、35.5%、82.8%,P53蛋白表达下降42.7%（均P<0.01）。与PM_2.5组比较,PM_2.5+SB203580组C-MYC、C-FOS、K-RAS和p38MAPK蛋白表达分别下降37.7%、16.2%、19.6%和25.9%,P53蛋白表达上升43.5%（P<0.01或P<0.05）。结论 p38MAPK抑制剂明显影响PM_2.5对癌基因表达的作用,提示p38MAPK信号通路在PM_2.5致癌基因表达作用中发挥重要作用。

Effects of PM2.5 on oncogene expression via p38MAPK signal pathway in HBE cells

Objective To investigate the effects of PM_2.5 on oncogene expression via p38MAPK signaling pathway in human bronchial epithelial （HBE） cells. Methods Control group, PM_2.5 group, SB203580 group and PM_2.5+ SB203580 group were established. HBE cells were treated with 10 µmol/L p38MAPK inhibitor SB203580 for 30 min, then cultured in serum-free DMEM medium for 24 h as SB203580 group; HBE cells were treated with 50 μg/mL PM_2.5 for 24 h as PM_2.5 group; HBE cells were treated with10 µmol/L SB203580 for 30 min, then exposed to 50 μg/mL of PM_2.5 for 24 h as the PM_2.5+SB203580 group. The mRNA and protein expression levels of C-MYC, C-FOS, K-RAS, P53 and p38MAPK were detected by real-time PCR and Western blot. Results PCR results showed that compared with the control group, the mRNA expression of C-MYC, C-FOS, K-RAS, p38MAPK in the PM2.5 group increased by 54.0%, 49.2%, 96.1%, 74.1%, and P53 decreased by 49.1%. Compared with the PM_2.5 group, the mRNA expression of C-MYC, C-FOS, K-RAS and p38MAPK in the PM_2.5+SB203580 group decreased by 21.4%, 20.8%, 39.3%, 21.4%, and P53 increased by 43.1% （P<0.01 or P<0.05）. Western blot results showed that compared with the control group, the protein expression levels of C-MYC, C-FOS, K-RAS, p38MAPK in the PM_2.5 group increased by 110.6%, 46.7%, 35.5%, 82.8%, and P53 decreased by 42.7% （all P<0.01）. Compared with the PM_2.5 group, the protein expression levels of C-MYC, C-FOS, K-RAS, p38MAPK in the PM2.5+SB203580 group decreased by 37.7%, 16.2%, 19.6%, 25.9%, and P53 increased by 43.5% （P<0.01 or P<0.05）. Conclusion The p38MAPK inhibitor obviously influenced the effects of PM_2.5 on oncogene expression, indicating that p38MAPK signaling pathway plays an important role in PM_2.5-induced oncogene expression.