Ad-PTEN对人小细胞肺癌NCI-H446细胞生长的抑制作用

摘要

目的 研究重组腺病毒第10号染色体同源丢失性磷酸酶张力蛋白基因(PTEN)对小细胞肺癌的抑癌增效和化疗增敏效应及其分子机制.方法 采用重组腺病毒载体PTEN(简称Ad-PTEN)感染QBI-293A细胞,并用该细胞进行病毒扩增和效价测定.将Ad-PTEN感染NCI-H446小细胞肺癌细胞.分为5组:PBS组、空载体Ad组、Ad-PTEN组、顺铂(DDP)组和Ad-PTEN+ DDP组,Western blot鉴定PTEN基因表达,MTT法和流式细胞仪(FCM)检测Ad-PTEN对NCI-H446小细胞肺癌细胞的生长抑制和诱导凋亡的增效作用,用RT-PCR检测细胞凋亡相关基因p53、bax、caspase-3、bcl-2、和survivin的转录.结果 Ad-PTEN可在QBI-293A细胞中增殖.Ad-PTEN感染NCI-H446细胞后,Western blot检测到了PTEN基因的表达.Ad-PTEN组、DDP组、Ad-PTEN+ DDP组体外能明显抑制人NCI-H446小细胞肺癌细胞的生长和诱导凋亡,且Ad-PTEN+ DDP组效应较Ad-PTEN组、DDP组更为显著(均P＜0.05).Ad-PTEN组、DDP组、Ad-PTEN+ DDP组的NCI-H446细胞中的p53、bax及caspase-3基因表达均上调,而Bcl-2和Survivin基因表达均下调,这些凋亡相关基因的上调或下调的表达趋势以Ad-PTEN+ DDP组最显著(均P＜0.05).结论 Ad-PTEN体外可抑制NCI-H446小细胞肺癌细胞生长,Ad-PTEN对DDP的细胞毒作用具有增敏效应,其机制可能与上调p53、bax及caspase-3基因表达和下调bcl-2和survivin基因表达有关.%293 A cells, the titration was 108pfu/mL. The expressions of PTEN in NCI-H446 cells were detected by Western blot. Adenovirus-mediated PTEN significantly inhibited NCI-H446 cell growth, induced cell ap-optosis in vitro. The p53, bax, and caspase-3 expression of NCI-H446 cells significantly increased in the Ad-PTEN group, DDP group, Ad-PTEN + DDP group, while Bcl-2 and Survivin gene expression significantly reduced; and in the Ad-PTEN + DDP group it was most significant(P <0. 05)- Conclusion Ad-PTEN can inhibit small cell lung cancer NCI-H446 cells in vitro, Ad-PTEN to DDP cytotoxicity with a sensitizing effect. Its mechanism may be related to increaseing the expression level of p53 、 bax and caspase-3 and reducing the expression level of bcl-2 and survivin gene.