Repair of furocoumarin adducts in mammalian cells

Journal Article · Sat Dec 01 04:00:00 EST 1984 · Natl. Cancer Inst. Monogr.; (United States)

OSTI ID:5642418

Zolan, M E; Smith, C A; Hanawalt, P C

DNA repair was studied in cultured mammalian cells treated with the furocoumarins 8-methoxypsoralen (8-MOP), aminomethyl trioxsalen, or angelicin and irradiated with near UV light. The amount of DNA cross-linked by 8-MOP in normal human cells decreased by about one-half in 24 hours after treatment; no decrease was observed in xeroderma pigmentosum cells, group A. At present, it is not known to what extent this decrease represents complete repair events at the sites of cross-links. Furocoumarin adducts elicited excision repair in normal human and monkey cells but not in xeroderma pigmentosum group A cells. This excision repair resembled in several aspects that elicited by pyrimidine dimers, formed in DNA by irradiation with 254-nm UV light; however, it appeared that for at least 8-MOP and aminomethyl trioxsalen, removal of adducts was not as efficient as was the removal of pyrimidine dimers. A comparison was also made of repair in the 172-base-pair repetitive alpha-DNA component of monkey cells to repair in the bulk of the genome. Although repair elicited by pyrimidine dimers in alpha-DNA was the same as in the bulk DNA, that following treatment of cells with either aminomethyl trioxsalen or angelicin and near UV was markedly deficient in alpha-DNA. This deficiency reflected the removal of fewer adducts from alpha-DNA after the same initial adduct frequencies. These results could mean that each furocoumarin may produce several structurally distinct adducts to DNA in cells and that the capacity of cellular repair systems to remove these various adducts may vary greatly.

• Research Organization: Stanford Univ., CA
• OSTI ID: 5642418
• Journal Information: Natl. Cancer Inst. Monogr.; (United States), Journal Name: Natl. Cancer Inst. Monogr.; (United States) Vol. 66; ISSN NCIMA
• Country of Publication: United States
• Language: English

Related Subjects

560121* -- Radiation Effects on Cells-- External Source-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ADDUCTS
ANIMAL CELLS
ANIMALS
ANTICOAGULANTS
BIOLOGICAL EFFECTS
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
CELL CULTURES
CHEMICAL REACTIONS
COUMARINS
CROSS-LINKING
DISEASES
DNA ADDUCTS
DNA REPAIR
DNA REPLICATION
DRUGS
ELECTROMAGNETIC RADIATION
HEMATOLOGIC AGENTS
HETEROCYCLIC COMPOUNDS
MAMMALS
MAN
MONKEYS
NEAR ULTRAVIOLET RADIATION
NUCLEIC ACID REPLICATION
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
POLYMERIZATION
PRIMATES
PSORALEN
PYRIMIDINE DIMERS
RADIATIONS
RECOVERY
REPAIR
SKIN DISEASES
ULTRAVIOLET RADIATION
VERTEBRATES
XERODERMA PIGMENTOSUM