p16基因抑制食管癌细胞生长的研究

p16 gene suppresses growth of human esophageal carcinoma cells

目的 探讨ｐ１６ 基因对食管癌细胞生长的抑制作用，为食管癌致癌机理的研究和基因治疗提供理论基础。方法 我们采用基因转染技术，将全长野生型ｐ１６ ｃＤＮＡ转染到经亚硝胺诱发的人胎儿食管癌细胞系中，该细胞内源性ｐ１６ 基因已发生纯合性缺失。结果 转染ｐ１６ 基因的食管癌细胞生长受到抑制，其在软琼脂上克隆形成能力降低了大约４ 倍。对细胞周期分析表明，处在Ｇ０ ～Ｇ１ 期的细胞由３３７ ％ 增加到６８６ ％ 。经Ｄｏｔｂｌｏｔ 和Ｗｅｓｔｅｒｎ ｂｌｏｔ 杂交证实，有外源ｐ１６ ｍＲＮＡ及蛋白的表达，说明ｐ１６ 蛋白具有生长抑制功能，其作用是通过介导Ｇ１ 阻止完成的。结论 野生型ｐ１６ 基因导入ｐ１６ 基因功能缺失的细胞，能恢复其抑制癌细胞生长的功能。

Objective To explore the effect of p16 gene on the growth inhibition of esophageal carcinoma cell line NEC.Methods The full length of wild type p16 cDNA was transfected into the esophageal carcinoma cell line of human fetus induced by N methyl N benzylnitrosamine (NMBzA). In these esophageal carcinoma cell, p16 gene was homozygously deleted.Results Expression of exogenous p16 gene in NEC cells was identified by dot blot and Western blot analyses. The growth rate of NEC transfected with p16 gene (NEC p16) was markedly suppressed. Colony formation in soft agar was also decreased significantly. Cell cycle analysis by flow cytometry showed that the number of cells in G 1 G 0 phase of NEC p16 cells was significantly increased while cells in S and G 2+ M phase was decreased compared to that of the control NEC cells.Conclusion Transduction of wild type p16 gene into p16 gene depleted esophageal cancer cells can restore its suppressive effect on cell growth by arrest of cell cycle at G 1 phase.