Molecular Cloning and Characterization of a Novel Nitroreductase Gene,NOR_1,Possibly Involved in Chemical Carcinogenesis of NPC
NIE Xin min, ZHOU Ming, TANG Ke, ZHANG Bi cheng, XIANG Juan juan, XIONG Wei, L�P Hong bin, LI Xiao ling, LI Gui yuan * (Cancer Research Institute, Xiangya School of Medicine, Central South University,Changsha 410078, China)
The expression of ESTW95442 is down regulated in nasopharyngeal carcinoma cell line CNE 1, in comparison with normal nasopharyngeal epithelial cell, which was confirmed by cDNA microarray analysis. Subsequently, the novel gene, NOR 1 (GenBank Accession No.AF462348), corresponding to ESTW95442 was cloned by cDNA cloning and bioinformatics analysis. Northern blot analysis showed that NOR 1 gene had two transcripts (1.6 kb, 1.2 kb) and expressed in almost normal human tissues. RT PCR analysis showed that the expression of NOR 1 was also down regulated in nasopharyngeal carcinoma (NPC) biopsies. However, NOR 1 had high enzyme activity in CNE 1 compared with normal nasopharyngeal epithelial cell. The conditioned media of CNE 1 cells transfected with full length NOR 1 cDNA showed that the NOR 1 had the similar activity to the bacterial nitroreductase NTR, which could convert monofunction alalkylating agent, CB1954 ([5 aziridin 1 yl] 2,4 dinitrobenzamide) into a toxic form by reducing the 4 nitro group of CB1954. The findings suggest that the NOR 1 gene may play an important role in the formation of chemical carcinogen and carcinogenesis of NPC by its nitrosation function and high enzyme activity.
.Molecular Cloning and Characterization of a Novel Nitroreductase Gene,NOR_1,Possibly Involved in Chemical Carcinogenesis of NPC [J] Chinese Journal of Biochemistry and Molecular Biol, 2003,V19(04 ): 423-423