已建株鼻咽癌细胞的PLUNC基因启动子区序列多态性分析

Sequence Polymorphism Analysis of the Promoter Region of PLUNC Gene in Nasopharyngeal Cancer Cell Lines

目的检测人类标准鼻咽癌细胞中是否存在已知的PLUNC基因启动子-437bp-＋87bp区域的单核苷酸多态性（SNP）。以便进一步探索SNP与鼻咽癌的关系。方法采用PCR产物直接测序的方法，对7株体外培养的鼻咽癌细胞基因组DNA的PLUNC基因启动子区进行序列分析。结果发现7株PLUNC基因的启动子区皆存在已知的3个SNP位点（1888、2128和N2）和未知一个突变位点（N1），其测观杂合度分别为85．7％、100％、100％和28．6％。其中3个已知SNP位点在筛查的细胞株中均存在T-C的突变，而且SUNE-1鼻咽癌细胞株的1888位点基因型为突变纯合子CC型。结论体外培养的标准鼻咽癌细胞株中存在已知的3个SNP位点（1888、2128和N2）的突变现象，且突变率为100％；1888位点鼻咽癌易患型（CC型）已在体外稳定建株；首次发现启动子-195bp区域N1突变位点。

Objective To nasopharyngeal cancer cells in detect the known single nucleotide polymorphism （SNP） of standard the region -437 bp N ＋ 87 bp of PLUNC promoter and to further explore the relationship between the nasopharyngeal carcinoma and SNP. Methods The PLUNC gene promoter sequences of seven nasopharyngeal cancer cells in vitro were PCR-amplified and then sequenced. Results Wee found that the seven cell lines contained three existent SNP sites （ 1888, 2128 and N2） and one unknown mutation point （ N1 ） in the promoter region of the PLUNC gene. The heterozygosity was 85. 7% , 100%, 100% ands28. 6%. The mutations of T → C on three known SNP sites existed in all cell lines. Furthermore, the genotype on 1888 SNP site in SUNE-1 nasopharyngeal carcinoma cell line was homozygous CC type. Conclusion The standard nasopha- ryngeal carcinoma cell lines in vitro also displayed the mutation phenomenon on the three knownSNP sites （1888. 2128 and N2）, with 100% mutation rate. Susceptibility gene type （CC type） of nasopharyngeal carcinoma on 1888 site had been stably established in vitro. N1 mutation site on the -195 bp region of the promoter was first discovered.