Premium
DNA REPAIR IN V‐79 CELLS TREATED WITH COMBINATIONS OF PHYSICAL AND CHEMICAL CARCINOGENS*
Author(s) -
Ahmed Farid E.,
Setlow R. B.
Publication year - 1980
Publication title -
photochemistry and photobiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.818
H-Index - 131
eISSN - 1751-1097
pISSN - 0031-8655
DOI - 10.1111/j.1751-1097.1980.tb04032.x
Subject(s) - methyl methanesulfonate , dmba , xeroderma pigmentosum , chemistry , epoxide , carcinogen , dna repair , dna damage , chinese hamster , limiting , dna , nucleotide excision repair , bromodeoxyuridine , microbiology and biotechnology , biochemistry , biology , carcinogenesis , mechanical engineering , engineering , gene , catalysis , cell growth
— Excision repair of DNA damage was measured by the photolysis of bromodeoxyuridine incorporated into parental DNA during repair in Chinese hamster V‐79 cells treated with 254 nm of ultraviolet radiation (UV), 7,12‐dimethylbenz[ a ]anthracene 5,6‐oxide (DMBA‐epoxide), N‐acetoxy‐2‐acetylaminofluorene (AAAF), 4‐nitroquinoline 1‐oxide (4NQO), 2‐methoxy‐6‐chloro‐9‐[3(ethyl‐2‐chloroethyl)‐aminopropylamino]acridine dihydrochloride (ICR‐170), X‐rays, ethylmethanesulfonate (EMS), methyl methanesulfonate (MMS) and combinations of these agents. Compared to normal human cells V‐79 were defective in repair of UV lesions and the lesions induced by the UV‐mimetic chemicals. The extent of the defects varied from 10 to 50% and was similar to those in Xeroderma pigmentosum group C cells (XP C). V‐79 cells repaired X‐ray damage and damage from the alkylating agents EMS and MMS to the same extent as human cells. Repair was additive after a combination of UV plus MMS indicating, as expected, that there are different rate‐limiting steps for removal of the damages from these agents. Repair was less than additive in cells treated with UV plus ICR‐170, AAAF plus ICR‐170, AAAF plus 4NQO, and 4NQO plus ICR‐170 and approximately equal to that observed for the higher of the two agents separately, indicating that there may be similar rate‐limiting steps for removal of lesions. Although the results on repair after combinations of UV plus 4NQO, UV plus DMBA‐epoxide or X‐rays plus MMS were difficult to interpret, there was not any inhibition of repair in these combinations.