Isolation of camptothecin-sensitive chinese hamster cell mutants: phenotypic heterogeneity within the ataxia telangiectasia-like XRCC8 (irs2) complementation group.

Using a replica microwell method, four Chinese hamster lines which exhibit hypersensitivity to the topoisomerase I inhibitor camptothecin, designated CM1, CM2, CM3 and CM6, have been isolated. Their sensitivity towards camptothecin varied from 3.5- to 8.2-fold with relative sensitivity as follows: CM2 < CM3 < CM6 < CM1. Genetic analysis of the CM mutants has established that CM1, CM3 and CM6 fail to complement each other and can each be assigned to the irs2 (XRCC8) complementation group. The mutant CM2 could not be definitively assigned to a complementation group because it presented a semi-dominant phenotype. In contrast to their sensitivity to camptothecin, the four CM mutants were less sensitive (1.1- to 2.2-fold) to the topoisomerase II inhibitors etoposide and adriamycin, although CM1, CM3 and CM6 were more sensitive (2.5- to 3. 8-fold) to streptonigrin (a free radical generator and a topoisomerase II inhibitor). All four mutant lines displayed an increased sensitivity to the bifunctional alkylating agent mitomycin C (2.4- to 5.1-fold). Surprisingly, given their assignment to the irs2 (XRCC8) complementation group, CM1, CM3 and CM6 displayed only a minor increase in sensitivity to ionizing radiation (1.6-fold or less). Similar sensitivity of these CM mutants was observed for the radiomimetic compound bleomycin (1.7-fold sensitive or less). This study indicates that XRCC8 mutants are isolated at high frequency from the parent line V79 and that phenotypic heterogeneity amongst the irs2 (XRCC8) complementation group is greater than previously encountered. Mutations in different regions of the XRCC8 gene may be responsible for the differing cellular phenotypes. Hamster XRCC8 mutants show phenotypic similarities to cultured cells from ataxia telangiectasia and Nijmegen break syndrome (NBS) patients and are likely to be defective in the same pathway in which the ATM (ataxia telangiectasia-mutated) and the NBS genes operate.

[1]  N. J. Jones,et al.  The isolation and genetic analysis of V79-derived etoposide sensitive Chinese hamster cell mutants: two new complementation groups of etoposide sensitive mutants. , 1999, Mutation research.

[2]  M. Jasin,et al.  Mammalian XRCC2 promotes the repair of DNA double-strand breaks by homologous recombination , 1999, Nature.

[3]  G. Verhaegh,et al.  Immortalization and characterization of Nijmegen Breakage syndrome fibroblasts. , 1999, Mutation research.

[4]  M. Meyn.  Ataxia‐telangiectasia, cancer and the pathobiology of the ATM gene , 1999, Clinical genetics.

[5]  W. de Laat,et al.  Molecular mechanism of nucleotide excision repair. , 1999, Genes & development.

[6]  L. Thompson.  Chinese hamster cells meet DNA repair: an entirely acceptable affair. , 1998, BioEssays : news and reviews in molecular, cellular and developmental biology.

[7]  M. Muller,et al.  Ultraviolet-induced DNA damage stimulates topoisomerase I-DNA complex formation in vivo: possible relationship with DNA repair. , 1998, Cancer research.

[8]  M. Gatei,et al.  Isolation of full-length ATM cDNA and correction of the ataxia-telangiectasia cellular phenotype. , 1997, Proceedings of the National Academy of Sciences of the United States of America.

[9]  P. Jeggo.  DNA-PK: at the cross-roads of biochemistry and genetics. , 1997, Mutation research.

[10]  M. Hoekstra.  Responses to DNA damage and regulation of cell cycle checkpoints by the ATM protein kinase family. , 1997, Current opinion in genetics & development.

[11]  Y. Shiloh,et al.  Fragments of ATM which have dominant-negative or complementing activity , 1997, Molecular and cellular biology.

[12]  J. Wang,et al.  Mechanisms of cell killing by drugs that trap covalent complexes between DNA topoisomerases and DNA. , 1996, Molecular pharmacology.

[13]  M. Oshimura,et al.  The defect in the AT-like hamster cell mutants is complemented by mouse chromosome 9 but not by any of the human chromosomes. , 1996, Mutation research.

[14]  L. Bracco,et al.  Modulation of DNA topoisomerase I activity by p53. , 1996, Biochemistry.

[15]  D. Ross,et al.  Role of NAD(P)H:quinone oxidoreductase (DT-diaphorase) in cytotoxicity and induction of DNA damage by streptonigrin. , 1996, Biochemical pharmacology.

[16]  N. Osheroff,et al.  Topoisomerase Poisons: Harnessing the Dark Side of Enzyme Mechanism (*) , 1995, The Journal of Biological Chemistry.

[17]  P. Jeggo,et al.  Nomenclature of human genes involved in ionizing radiation sensitivity. , 1995, Mutation research.

[18]  R. Tebbs,et al.  Correction of chromosomal instability and sensitivity to diverse mutagens by a cloned cDNA of the XRCC3 DNA repair gene. , 1995, Proceedings of the National Academy of Sciences of the United States of America.

[19]  M. Lovett,et al.  A single ataxia telangiectasia gene with a product similar to PI-3 kinase. , 1995, Science.

[20]  F. Zunino,et al.  Unique sequence specificity of topoisomerase II DNA cleavage stimulation and DNA binding mode of streptonigrin. , 1994, The Journal of biological chemistry.

[21]  D. Boothman,et al.  Down-regulation of topoisomerase I in mammalian cells following ionizing radiation. , 1994, Cancer research.

[22]  L. Thompson,et al.  An interaction between the mammalian DNA repair protein XRCC1 and DNA ligase III , 1994, Molecular and cellular biology.

[23]  R. Roeder,et al.  Identification of human DNA topoisomerase I as a cofactor for activator-dependent transcription by RNA polymerase II. , 1993, Proceedings of the National Academy of Sciences of the United States of America.

[24]  S. Ellard,et al.  Cellular and chromosomal hypersensitivity to DNA crosslinking agents and topoisomerase inhibitors in the radiosensitive Chinese hamster irs mutants: phenotypic similarities to ataxia telangiectasia and Fanconi's anaemia cells. , 1993, Carcinogenesis.

[25]  H. Gersbach,et al.  Various inhibitors of DNA topoisomerases diminish repair-specific DNA incision in UV-irradiated human fibroblasts. , 1993, Carcinogenesis.

[26]  D. Reinberg,et al.  DNA topoisomerase I is involved in both repression and activation of transcription , 1993, Nature.

[27]  G. Verhaegh,et al.  Co-dominance of radioresistant DNA synthesis in a group of AT-like Chinese hamster cell mutants. , 1993, Cytogenetics and cell genetics.

[28]  P. Bryant,et al.  Radiosensitive Chinese hamster irs2 cells show enhanced chromosomal sensitivity to ionizing radiation and restriction endonuclease induced blunt-ended double-strand breaks. , 1993, Mutagenesis.

[29]  A. Collins,et al.  Mutant rodent cell lines sensitive to ultraviolet light, ionizing radiation and cross-linking agents: a comprehensive survey of genetic and biochemical characteristics. , 1993, Mutation research.

[30]  Ilan R. Kirsch,et al.  The Causes and Consequences of Chromosomal Aberrations , 1992 .

[31]  W. Kaufmann,et al.  Inhibition of replicon initiation in human cells following stabilization of topoisomerase-DNA cleavable complexes , 1991, Molecular and cellular biology.

[32]  H. Strutt,et al.  Camptothecin cytotoxicity in mammalian cells is associated with the induction of persistent double strand breaks in replicating DNA. , 1991, Nucleic acids research.

[33]  Z. Darżynkiewicz,et al.  The S-phase cytotoxicity of camptothecin. , 1991, Experimental cell research.

[34]  J. Thacker,et al.  The genetic basis of resistance to ionising radiation damage in cultured mammalian cells. , 1991, Mutation research.

[35]  C. Bendixen,et al.  Camptothecin-stabilized topoisomerase I-DNA adducts cause premature termination of transcription. , 1990, Biochemistry.

[36]  J. Thacker,et al.  DNA-break repair, radioresistance of DNA synthesis, and camptothecin sensitivity in the radiation-sensitive irs mutants: comparisons to ataxia-telangiectasia cells. , 1990, Mutation research.

[37]  C. Robson,et al.  DNA repair in radiation sensitive mutants of mammalian cells: possible involvement of DNA topoisomerases. , 1990, International journal of radiation biology.

[38]  L. Thompson,et al.  Biochemical and genetic analysis of the Chinese hamster mutants irs1 and irs2 and their comparison to cultured ataxia telangiectasia cells. , 1990, Mutagenesis.

[39]  Y. Pommier,et al.  Differential requirement of DNA replication for the cytotoxicity of DNA topoisomerase I and II inhibitors in Chinese hamster DC3F cells. , 1989, Cancer research.

[40]  L. Liu,et al.  Arrest of replication forks by drug-stabilized topoisomerase I-DNA cleavable complexes as a mechanism of cell killing by camptothecin. , 1989, Cancer research.

[41]  A. Natarajan,et al.  Ataxia-telangiectasia-like Chinese hamster V79 cell mutants with radioresistant DNA synthesis, chromosomal instability, and normal DNA strand break repair. , 1989, Cancer research.

[42]  F. Palitti,et al.  Induction of chromosomal aberrations and SCE by camptothecin, an inhibitor of mammalian topoisomerase I. , 1989, Mutation research.

[43]  D. Boothman,et al.  Inhibition of potentially lethal DNA damage repair in human tumor cells by beta-lapachone, an activator of topoisomerase I. , 1989, Cancer research.

[44]  P. Smith,et al.  Enhanced sensitivity to camptothecin in ataxia-telangiectasia cells and its relationship with the expression of DNA topoisomerase I. , 1989, International journal of radiation biology.

[45]  L. Liu,et al.  Identification of mammalian DNA topoisomerase I as an intracellular target of the anticancer drug camptothecin. , 1988, Cancer research.

[46]  M. Muller,et al.  Stabilization of type I topoisomerase-DNA covalent complexes by actinomycin D. , 1988, Proceedings of the National Academy of Sciences of the United States of America.

[47]  J. Wang,et al.  Involvement of DNA topoisomerase I in transcription of human ribosomal RNA genes. , 1988, Proceedings of the National Academy of Sciences of the United States of America.

[48]  M. Zdzienicka.  Mutagen-sensitive cell lines are obtained with high frequency in V79 Chinese cells , 1987 .

[49]  J. Thacker,et al.  Isolation and cross-sensitivity of X-ray-sensitive mutants of V79-4 hamster cells. , 1987, Mutation research.

[50]  R. Hertzberg,et al.  Camptothecin induces protein-linked DNA breaks via mammalian DNA topoisomerase I. , 1985, The Journal of biological chemistry.

[51]  J. Wang,et al.  Drosophila DNA topoisomerase I is associated with transcriptionally active regions of the genome. , 1984, Proceedings of the National Academy of Sciences of the United States of America.

[52]  J. Thacker.  The chromosomes of a V79 Chinese hamster line and a mutant subline lacking HPRT activity. , 1981, Cytogenetics and cell genetics.

[53]  K. Brookman,et al.  A screening method for isolating DNA repair-deficient mutants of CHO cells , 1980, Somatic cell genetics.