EGCG抑制Nicotine诱导肺腺癌H1299细胞JAK2/STAT3 mRNA的表达研究

为探索EGCG对Nicotine诱导肺癌细胞增殖的抑制作用,本研究通过MTT实验筛选出EGCG、Nicotine对肺腺癌细胞H1299的最佳作用浓度,利用实时荧光定量PCR技术检测EGCG、Nicotine对H1299细胞中Bax、Bcl-2、Jak2和Stat3基因mRNA相对表达量的变化。实验结果表明,EGCG对H1299细胞的半抑制浓度IC₅₀值约为32βμmol·L^-1（24βh）、15βμmol·L^-1（48βh）;1βμmol·L^-1的Nicotine对H1299细胞促增殖作用明显;以15βμmol·L^-1的EGCG预处理H1299细胞24βh可显著下调1βμmol·L^-1 Nicotine的促增殖作用（P<0.05）。1βμmol·L^-1的Nicotine处理H1299细胞可明显降低JAK2/STAT3信号通路中Bax基因mRNA的表达,增加Bcl-2、Jak2、Stat3基因的mRNA表达;15βμmol·L^-1 EGCG预处理H1299细胞可反向调控Nicotine诱导所致JAK2/STAT3信号通路中Jak2、Stat3和Bax、Bcl-2基因表达量的变化,结果具有显著性差异（P<0.05）。由此可知,EGCG对Nicotine诱导的肺腺癌H1299细胞增殖及JAK2/STAT3信号通路中促增殖基因mRNA的表达起抑制作用。

Research on the Inhibitory Effect of EGCG on Nicotine in Inducing H1299 Cancer Cell JAK2/STAT3 mRNA Expression

In order to explore the inhibitory effect of EGCG on nicotine which induced lung cancer cells proliferation, this study selected the optimal concentrations of EGCG and nicotine on lung adenocarcinoma cancer cell H1299 by MTT experiment, and detected mRNA relative expression levels of Bax, Bcl-2, Jak2 and Stat3 genes in H1299 cells using qRT-PCR technique. Experiment results showed that the IC50 of EGCG on H1299 lung adenocarcinoma cells is about 32 μmol·L-1 (treated 48 h) and 15 μmol·L-1 (treated 24 h), nicotine obviously promotes the proliferation of H1299 lung adenocarcinoma cell at 1 μmol·L-1 concentration treatment. Pretreatment of H1299 cells with 15μmol·L-1 EGCG (24 h) can significantly down-regulate the promotion of proliferation induced by 1 μmol·L-1 Nicotine (P<0.05). Using 1 μmol·L-1 nicotine to treat H1299 cells has showed that nicotine significantly reduce the mRNA expression level of Bax gene, increase the mRNA expression levels of Bcl-2, Jak2 and Stat3 genes in the JAK2/STAT3 signal pathway. Pretreatment of H1299 cells with 15 μmol·L-1 EGCG (24 h) can be observed that EGCG significantly retroregulated the mRNA expression levels of Bax, Bcl-2, Jak2 and Stat3 genes in the JAK2/STAT3 signal pathway, and got the results with significant differences (P<0.05). In conclusion, EGCG plays important role in suppressing the survival rates of H1299 cells and mRNA expression level of JAK2/STAT3 signaling pathway induced by nicotine.