外源性p16基因对人肺癌细胞生物学特性的影响

目的：研究外原性p16基因对肺癌细胞生物学特性的影响。方法：利用脂质体介导的基因转染方法将外源性p16基因转入p16基因缺陷的人肺腺癌细胞株A549中，用逆转录聚合酶链反应（RT－PCR）及免疫组化的方法检测p16基因的表达，同时观察转染后细胞恶性生长的变化。结果：外源性p16基因在A549细胞中能稳定表达，转染后A549细胞生长速度明显减慢,在软琼脂上形成克隆的能力降低。流式细胞仪检测显示A549细胞G1期阻滞并发生了凋亡，接种裸鼠后致瘤性降低，肿瘤生长明显减慢。结论：外源性p16基因导入人肺癌细胞株A549中可稳定表达并抑制细胞的恶性生长，同时诱导调亡。

Effect of exogenous p16 gene on biological behaviors of human lung cancer

Objective To evaluate the biological effects of tumor suppressor gen e p16 on human lung cancer cells with p16 gene deletion. Methods p16-pcDNA3 was transfected into lung cancer cell line A549 using lipofectin, in which p16 gene was homozygously deleted. Biological behaviors of the transfected cell line were investigated both in vitro and in vivo. The expressions of p16 mRNA and protein were detected by RT-PCR and immunohistochemistry. Results There was stable exp r ession of p16 in the transfected cell line A549. Exogenous p16 gene significantl y slowed down the growth of A549 cells as compared with the control. Flow Cytome try showed that the transfected cells were stagnated in G1 phage of cell cycle accompanying with apoptosis. In addition, clonogenic assay showed that the numbe r of colony in soft agar was decreased in transfected cells as well. In vivo, a suppressed tumorigenicity and significantly decreased growth rate were shown in nude mice injected with A549 cells transfected with p16-pcDNA3 , as compared w ith those in mice injected with either original A549 or A549 transfected with pc DNA3. Conclusion Exogenous p16 gene can express stably in human lung cancer A54 9 cell line; exogenous p16 gene transfection induces apoptosis in lung cancer ce lls with p16 deletion and inhibits growth of the tumor in nude mice.