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QUANTITATIVE PATTERN RECOGNITION FOR STRUCTURE-CARCINOGENIC ACTIVITY RELATIONSHIP OF N-NITROSO COMPOUNDS BASED UPON DI-REGION THEORY

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Science china chemistry 1989年第7期32卷 776-790页

作者：戴乾圜钟儒刚 Center for chemistry & bioengineering of cancer Beijing Polytechnic University

In this paper, it is evidenced by the quantitative structu re-carcinogenic activity relation-ship (QSCAR) and the pattern recognition treatment of N-nitroso compounds (NNC) that thekey step of carcinogenesis induced by NNC is the cross-linking on the complementary basepair of DNA, through the bifunctional alkylation between α-carbon and another carbonwithin the same chain. The alkylation by the α-carbon atom is through the diazonium salt,but that by the atom other than the α-position is through the active ester formed from thehydroxylated metabolite of the chain. Therefore, the alkylation by the β-position of NNC,or by its γ-position under suitable conditions, of which the distances from the α-positionboth approach 2. 80-3. 00 A, would be the most favourable positions along with the α-posi-tion for the cross-linking to occur between the complementary base pairs of DNA, whichwill yield the carcinogenic activity of NNC. The above conception of bifunctional alkyla-tion can reduce the QSCAR of NNC to a reasonable structure-chemical reactivity relationshipunder the complex biological conditions, and is the successful extension of the Di-regiontheory to the carcinogenesis mechanism of the important NNC series. In the light of theabove viewpoint, for 153 NNCs including the nitrosamines and nitrosamides which havebeen tested reliably with animals, the correct discrimination ratio by quantitative patternrecognition according to carcinogenic activity indexes divided into 5 degrees comes up to ashigh as 97%.

关键词： N-nitroso compounds Di-region theory pattern recognition chemical carcinogenesis structure-carcinogenic activity relationship

A Theoretical Research on the Intermediate in the Reaction of N-Phosphorylamino-acid to form Peptide or Ribotide

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Chinese Chemical Letters 1998年第12期9卷 0-0页

作者： Ru Gang zhong Zhao Long LI Yu Fen ZHAO Qian Huan dai (Bioorganic Phosphorus chemistry Laboratory, Tsinghua university, beijing 100084)(Center for Chem. and Bioeng. of cancer Res., beijing polytechnic university, beijing 10002.. Tsing Hua Univ Bioorgan Phosphorus Chem Lab Beijing 100084 Peoples R China beijing Polytech Univ Ctr Chem & Bioengn Canc Res Beijing 100022 Peoples R China

In order to explain the high activity of N-phosphoryl-α-amino acids, ab initio and MNDO calculations are performed to study the reaction pathway of the intermediate formation from N-dimethylphosphoryl-α-alanine (DMP... 详细信息

关键词： Phosphoryl-α-amino acid reaction pathway quantum chemistry

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AM1 computational study on metabolites of l ,3-butadiene interstrand cross-linking DNA

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Chinese Science Bulletin 2000年第3期45卷 212-214页

作者： ZHOU Zhigang, dai Qianhuan & zhong rugang1. Center of Environmental Science, Peking university, beijing 100871, china 2. Center cancer chemistry and bioengineering, beijing polytechnic university beijing 10002.. china

The alkylating reactions of 1,2-epoxy-3,4-butene (EB) and 1,2,3,4-diepoxybutane (DEB)-the important metabolites of rodent carcinogenic 1,3-butadiene, with adenine and cytosine andinteraction with fragment of DNA on major groove-have been computed. Results show thatthere are little differences in activation energy between EB and DEB, so it is difficult to explain the fact that the mutagenicity of DEB is greater (about 100-fold) than that of EB by the ability of alkylation. it is also known that DEB can interstrand cross-link with DNA through two times alkylating reactions, whereas EB cannot. So this may contribute to the significant different genotoxicity of the two agents. Meanwhile, DEB can interstrand cross-link with many sequences of DNA in major groove vs. two in minor groove, which increases opportunity of interstrand cross-link with DNA in major groove. This difference may be the reason of base selection of DEB mutation. The deformation of some cross-linked DNA may also contribute to this

关键词： 1 3-butadiene carcinogenesis mutagenesis cross-linking with DNA AMI.

Mechanism of intramolecular mixed anhydride formation as intermediates in the reactions of N-phosphorylamino-acids──An MNDO research

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Chinese Science Bulletin 1998年第11期43卷 917-921页

作者： zhong rugang ZHAO Yufen dai Qianhuan Bioorganic Phosphorus chemistry Laboratory Department of ChemistryTsinghua UniversityBeijing 100022China Center for chemistry and bioengineering of cancer Research Beijing Poly technic UniversityBeijing 100022China.

N-phosphoryl-α-amino acids can react to form esters, peptides, phosphoryl ester-exchanged products and phosphoryl group migration products under mild conditions, which are very important in researches on arohebiont. It has been proposed that intramolecular mixed carboxylic-phosphoric anhydrides (IMCPAs) might be the common intermediates of the reactions, which are difficult to be experimentally observed because of their high activity. In this note, it has been revealed, by means of MNDO, that the IMCPAs are situated at the relatively minimal points of the potential surface and can form in a non-synchronous concerted reaction pathway that passes through a transition state with a hydrogen-bond-bridge structure. The results give a successful explanation to the structure and formation of IMCPAs and their ability to promote the various reactions mentioned above.

关键词： N-phosphorylamino-acid intramolecular mixed anhydride mechanism MNDO.

PM3 computation for the DNA complementary base paircross-linked by the metabolite of Benzo[a] pyrene

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Chinese Science Bulletin 1998年第2期43卷 175-175页

作者： Qianhuan dai Bo Qu rugang zhong Dawei Zheng Center for chemistry and bioengineering of cancer Beijing Polytechnic University Beijing China

Discusses PM3 computation for DNA complementary base pair cross-linked by the metabolite of Benzo[a]pyrene. Experimental procedure; Distance of positions.

关键词： base PM3 computation for the DNA complementary base paircross-linked by the metabolite of Benzo[a pyrene DNA

<i>In Situ</i>Detection of the p53-E6 and pRb-E7 Complex Formation in EC109 Cell by Proximity Ligation Assay

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Journal of cancer Therapy 2019年第4期10卷 336-344页

作者： Yangjunqi Wang Jintao Li Fan Li Shuying Li rugang zhong beijing Key Laboratory of Environmental & Viral Oncology College of Life Science & Bioengineering Beijing University of Technology Beijing China Department of Pathogenic Biology College of Basic Medicine Hebei United University Tangshan China

Human papillomavirus is an important cancer factor in many cancers. E6E7 is the important viral oncogene and plays an important role. It is known that its function is to regulate p53 and pRb. In this paper, in situdetection was performed to determine the interaction between them;the research provides visual evidence of their interaction. Research methods: In situ PLA reaction was used to detect the relationship between two different protein. Results: The quantity of the HPV18E6 expression is much higher than the expression of HPV18E7 protein in HeLa and EC109 cells;the interaction between p53-E6 and pRb-E7 was clearly observed and this effect could be visualized by this method. Conclusion: Interaction of the HPV18E6 protein combined with p53 protein and HPV18E7 protein combined with pRb protein could be visualized in cell.

关键词： HPV E6 HPV E7 p53 pRb PLA

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环境致癌物与病毒协同致癌作用的研究进展

病毒学报 2018年第4期34卷 601-609页

作者：贾帅楠李劲涛赵丽娇钟儒刚曾毅北京工业大学生命科学与生物工程学院环境与病毒肿瘤学北京市重点实验室北京100124 中国疾病预防控制中心病毒病预防控制所传染病预防控制国家重点实验室北京100052

癌症是威胁人类健康的重大疾病,其发病与环境、病原体、遗传和生活方式等多种因素有关。环境致癌物是诱发癌症的重要因素之一,如多环芳烃、亚硝胺和霉菌毒素等均为环境中广泛存在的典型致癌物,它们在体内经过代谢活化后导致DNA损伤最终... 详细信息

癌症是威胁人类健康的重大疾病,其发病与环境、病原体、遗传和生活方式等多种因素有关。环境致癌物是诱发癌症的重要因素之一,如多环芳烃、亚硝胺和霉菌毒素等均为环境中广泛存在的典型致癌物,它们在体内经过代谢活化后导致DNA损伤最终诱发癌症。病毒感染也是人类癌症发病的重要原因,如乙肝病毒（HBV）和丙肝病毒（HCV）能够诱发肝癌;EB病毒（EBV）在鼻咽癌的发生过程中起关键作用;人乳头瘤病毒（HPV）与宫颈癌和食管癌有关。然而,由于癌症发病机制复杂,仅考虑单一因素往往难以进行合理的解释。因此,明确不同致癌因素之间的协同作用对于揭示致癌作用机制具有重要意义。本文综述了近年来有关环境致癌物与病毒协同致癌作用的研究,以期为深入阐明肿瘤发生和发展的作用机制找到新的突破口,进而为相关癌症的防治提供新策略。

关键词：环境致癌物病毒协同致癌作用机制