phosphorus-radioisotopes and cuprous-chloride

phosphorus-radioisotopes has been researched along with cuprous-chloride* in 1 studies

Other Studies

1 other study(ies) available for phosphorus-radioisotopes and cuprous-chloride

Article	Year
Site-specific oxidation at GG and GGG sequences in double-stranded DNA by benzoyl peroxide as a tumor promoter. Biochemistry, 1999, Dec-21, Volume: 38, Issue:51 Benzoyl peroxide (BzPO), a free-radical generator, has tumor-promoting activity. As a method for approaching the mechanism of tumor promoter function, the ability of oxidative DNA damage by BzPO was investigated by using (32)P-labeled DNA fragments obtained from the human p53 tumor suppressor gene and c-Ha-ras-1 protooncogene. BzPO induced piperidine-labile sites at the 5'-site guanine of GG and GGG sequences of double-stranded DNA in the presence of Cu(I), whereas the damage occurred at single guanine residues of single-stranded DNA. Both methional and dimethyl sulfoxide (DMSO) inhibited DNA damage induced by BzPO and Cu(I), but typical hydroxyl radical (()OH) scavengers, superoxide dismutase (SOD) and catalase, did not inhibit it. On the other hand, H(2)O(2) induced piperidine-labile sites at cytosine and thymine residues of double-stranded DNA in the presence of Cu(I). Phenylhydrazine, which is known to produce phenyl radicals, induced Cu(I)-dependent damage at thymine residues but not at guanine residues. These results suggest that the BzPO-derived reactive species causing DNA damage is different from ()OH and phenyl radicals generated from benzoyloxyl radicals. BzPO/Cu(I) induced 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) formation in double-stranded DNA more effectively than that in single-stranded DNA. Furthermore, we observed that BzPO increased the amount of 8-oxodG in human cultured cells. Consequently, it is concluded that benzoyloxyl radicals generated by the reaction of BzPO with Cu(I) may oxidize the 5'-guanine of GG and GGG sequences in double-stranded DNA to lead to 8-oxodG formation and piperidine-labile guanine lesions, and the damage seems to be relevant to the tumor-promoting activity of BzPO. Topics: 5' Untranslated Regions; 8-Hydroxy-2'-Deoxyguanosine; Animals; Base Sequence; Benzoyl Peroxide; Carcinogens; Cattle; Clone Cells; Copper; Deoxyguanosine; DNA; DNA Damage; Free Radical Scavengers; Guanine; HL-60 Cells; Humans; Hydrogen Peroxide; Phenanthrolines; Phosphorus Radioisotopes; Thymus Gland	1999

Article

Year

Site-specific oxidation at GG and GGG sequences in double-stranded DNA by benzoyl peroxide as a tumor promoter.

Biochemistry, 1999, Dec-21, Volume: 38, Issue:51

Benzoyl peroxide (BzPO), a free-radical generator, has tumor-promoting activity. As a method for approaching the mechanism of tumor promoter function, the ability of oxidative DNA damage by BzPO was investigated by using (32)P-labeled DNA fragments obtained from the human p53 tumor suppressor gene and c-Ha-ras-1 protooncogene. BzPO induced piperidine-labile sites at the 5'-site guanine of GG and GGG sequences of double-stranded DNA in the presence of Cu(I), whereas the damage occurred at single guanine residues of single-stranded DNA. Both methional and dimethyl sulfoxide (DMSO) inhibited DNA damage induced by BzPO and Cu(I), but typical hydroxyl radical ((*)OH) scavengers, superoxide dismutase (SOD) and catalase, did not inhibit it. On the other hand, H(2)O(2) induced piperidine-labile sites at cytosine and thymine residues of double-stranded DNA in the presence of Cu(I). Phenylhydrazine, which is known to produce phenyl radicals, induced Cu(I)-dependent damage at thymine residues but not at guanine residues. These results suggest that the BzPO-derived reactive species causing DNA damage is different from (*)OH and phenyl radicals generated from benzoyloxyl radicals. BzPO/Cu(I) induced 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) formation in double-stranded DNA more effectively than that in single-stranded DNA. Furthermore, we observed that BzPO increased the amount of 8-oxodG in human cultured cells. Consequently, it is concluded that benzoyloxyl radicals generated by the reaction of BzPO with Cu(I) may oxidize the 5'-guanine of GG and GGG sequences in double-stranded DNA to lead to 8-oxodG formation and piperidine-labile guanine lesions, and the damage seems to be relevant to the tumor-promoting activity of BzPO.

Topics: 5' Untranslated Regions; 8-Hydroxy-2'-Deoxyguanosine; Animals; Base Sequence; Benzoyl Peroxide; Carcinogens; Cattle; Clone Cells; Copper; Deoxyguanosine; DNA; DNA Damage; Free Radical Scavengers; Guanine; HL-60 Cells; Humans; Hydrogen Peroxide; Phenanthrolines; Phosphorus Radioisotopes; Thymus Gland

1999