高低转移肺腺癌细胞系中肿瘤抑制基因p16、p21和p53表达研究

目的 探讨肿瘤抑制基因对肺腺癌细胞生长的抑制作用。方法 利用FuGene转染方式分别将p21和p16基因的表达质粒转入－对肺腺癌细胞系Anip973和AGZY83－a中，同时用含野生型p53 基因的腺病毒感染p16基因转染前后的这一对细胞系。对P16和P21蛋白过表达的细胞系进行了细胞生长曲线、克隆形成率、原位末端标记分析和流式细胞仪分析。结果 p16基因的过表达只能使细胞系的G1期细胞比例提高，但细胞生长曲线，克隆形成率均未出现改变，未检测到凋亡信号。P21蛋白过表达的一对细胞系细胞生长曲线斜率降低，克隆形成能力下降，并出现明显的G1期阻滞，但未检测到凋亡信号。p53基因感染AGZY83－a,Anip973及经过p16基因转染的细胞AGZY83－ap16和Anip973p16后呈现时间依赖性表达，细胞生长曲线和四唑盐比色法分析提高，野生型p53基因的大量表达明显抑制以上4种细胞的生长，Anip973和Anip973p16的生长抑制率高于AGZY83－a和AGZY83－ap16;Anip973p16和AGZY83-ap16的生长抑制率高于Anip973和AAGZY83－a。这4种细胞在感染p53后出现典型的凋亡信号。结论p16基因的过表达并不能抑制细胞系的生长，而p21基因的过表达通过G1期阻滞抑制这1对肺腺癌细胞的生长；野生型p53基因在AGZY83－a和Anip973中高效表达可产生明显的细胞生长抑制效应；野生型p53基因对肺腺癌高转移细胞系Anip973抑制作用更为明显。

Expression of tumor suppressor genes p16, p21 and p53 in a pair of lung adenocarcinoma cell lines with different metastasis potentials: Anip973 and AGZY83-a

OBJECTIVE: In order to investigate the suppression effect of tumor suppressor genes in lung adenocarcinoma. METHODS: p16 and p21 expression vectors were transfected into a pair of lung adenocarcinoma cell lines with different metastasis potentials: Anip973(high metastasis potential)and AGZY83-a (low metastasis potential). In the mean time, AGZY83-a, Anip973, AGZY83-ap16 and Anip973p16 were infected with recombinant adenovirus encoding wild- type p53 gene. The suppression effects of these genes were evaluated by cell growth curve, MTT, cloning efficiency assay, flow cytometric analysis and TUNEL technique. RESULTS: Overexpression of p16 gene in Anip973 and AGZY83-a could only lengthen the G(1) phase while increased expression of p21 in both of the cell lines was associated with significant lengthening of G(1) phase, decreased proliferation potential and decreased cloning efficiency. High efficient expression of wild-type p53 gene in AGZY83-a, Anip973, Anip973p16 and AGZY83-ap16 inhibited the growth of these four kinds of lung cancer cells and killed the cells in the end. Apoptosis was detected in all the four kinds of cells. The suppression effect of p53 gene was higher in Anip973 and Anip973p16 than in AGZY83-a and AGZY83-ap16 while co-expression of p53 and p16 in this pair of cell lines inhibited the cells more efficiently as compared with the expression of p53 gene. CONCLUSION: Increased expression of p21 gene suppressed the lung adenocarcinoma cells by G(1) arrest and the co-transfection of tumor suppressor genes p16 and p53 into the lung adenocarcinoma cell line proved more effective in lung cancer gene therapy.