摘要
目的：抑制细胞内的Ｏ６－甲基鸟嘌呤－ＤＮＡ甲基转移酶（ＭＧＭＴ）基因表达水平，逆转肿瘤细胞对嘧啶亚硝脲的耐药性。方法：本实验构建了三个表达ＭＧＭＴ反义ＲＮＡ的逆转录病毒载体（ｐＬＭＴＳＮＡＳ，ｐＬＭ５ＳＮＡＳ和ｐＬＭ３ＳＮＡＳ），并用它们转导ＨｅＬａＳ３肿瘤细胞，观察细胞在转导前后ＭＧＭＴ基因表达水平及其对嘧啶亚硝脲（ＡＣＮＵ）抗药性的变化。结果：研究发现针对ＭＧＭＴｍＲＮＡ５端的反义ＲＮＡ能够有效地降低ＨｅＬａＳ３细胞的ＭＧＭＴ基因表达水平（为对照细胞的３０％～４０％），并使细胞对ＡＣＮＵ的敏感性提高４．６倍；针对ＭＧＭＴｍＲＮＡ全长的反义ＲＮＡ，也能在一定程度上调节细胞的ＭＧＭＴ基因表达水平并增加细胞对ＡＣＮＵ的敏感性，而针对３端序列的反义ＲＮＡ对ＭＧＭＴ基因无调节作用。转导细胞对ＡＣＮＵ耐药性的变化与ＭＧＭＴ基因表达水平的抑制程度密切相关。结论：合适的反义ＲＮＡ能够有效地调节ＭＧＭＴ基因表达水平。
The intracellular O 6 methylguanine DNA methyltransferase (MGMT) may repair the DNA damage induced by nitrosourea drugs and protect tumor cells from the killing effects of nitrosoureas. In this study, three retroviral vectors (pLMTSN AS and pLM5SN AS and pLM3SN AS ) were constructed and transduced into HeLa S3 cells.The differences in MGMT gene expression levels as well as cellular resistance to l (4 Amino 2 methyl 5 pyrimidinyl) methyl 3 (2 chloroethyl) 3 nitrosourea (ACNU) before and after transduction were compared. It was found that antisense RNA targeting 5 region of MGMT mRNA exhibited effect in modulation MGMT gene expression (30～40% of HeLa S 3 cells) and that the transfectants became more sensitive to ACNU (DMF=4.6). Antisense RNA targeting the whole length of MGM mRNA also affected MGMT gene expression and enhanced cellular sensitivity to ACNU to a certain extent. 3region antisense RNA had no effect on MGMT modulation. There was close relationship between the degree of alteration in cellular resistance to ACNU and the degree of inhibition in MGMT gene expression. The results suggested that appropriate antisense RNA might nodulate MGMT gene expression and enhance the killing effects of ACNU on tumor cells.
出处
《中国肿瘤临床》
CAS
CSCD
北大核心
1999年第1期8-11,共4页
Chinese Journal of Clinical Oncology
基金
国家自然科学基金
关键词
MGMT基因
肿瘤
耐药性
反义RNA
嘧啶亚硝脲
O 6 methylguanine DNA Methyltransferase gene Drug resistance Antisense RNA ACNU
