p16基因抑制乳腺癌细胞MCF-7增殖的体外和体内实验研究

目的 :探讨p16基因对乳腺癌的治疗作用 ,为乳腺癌 p16的基因治疗提供实验依据。 方法 :构建p16的逆转录病毒载体 pLMSN ,包装成病毒后 ,体外转导p16基因纯合性缺失的乳腺癌细胞株MCF 7,Westernblot证明该基因在转导后的MCF 7细胞中有表达 ,用活细胞计数、流式细胞仪、形态观察等方法来检测 p16表达在体外对MCF 7细胞生物学行为的影响。进行SCID鼠体内成瘤实验和逆转录病毒直接注射SCID鼠乳腺癌模型的治疗性实验来观察 p16对乳腺癌细胞的体内抑制作用。 结果 :外源性 p16在MCF 7细胞中表达后 ,体外细胞发生形态改变 ,生长明显慢于对照细胞 ,流式细胞计数显示G1期细胞增多 ,细胞在SCID鼠体内成瘤性下降 ,p16逆转录病毒直接注射有使SCID鼠乳腺肿瘤缩小的趋势。结论 :p16逆转录病毒对p16基因纯合性缺失的乳腺癌有一定治疗意义

p16cDNA retrovirus inhibits the growth of breast cancer cell line MCF-7 in vitro and in vivo

Objective: To explore the therapeutic effect of introduction of the p16 gene into human breast cancer cell line MCF 7 via retroviral vector both in vitro and in vivo . Methods: Western blotting was done to detect p16 expression in MCF 7 cells after transduction. Cell counting, fluorescence activated cell sorting and morphological observation were used to evaluate the biological behavior changes of MCF 7 cells after p16 gene transfer. Tumor formation ability of MCF 7 and the effects of intratumoral injection of p16 retrovirus in solid breast tumor were tested in SCID mice. Results: The expression of p16 protein could be detected in MCF 7 p16 cells. MCF 7 cells transducted with p16 retrovirus showed proliferation inhibition and cell cycle arrest. Morphologic changes occurred also. The ability of tumor formation of MCF 7 p16 cells in SCID mice was 42% reduced. The tumor in SCID mice injected with the p16 retrovirus showed an average 30% reduction in weight compared with that of control retrovirus injected group. Conclusion: Our findings have strongly supported the fact that the tumor suppressor gene p16 is a candidate for breast cancer gene replacement therapy.