This research represents an investigation of the mechanisms of action of the cancer chemotherapeutic platinum coordination complexes, as well as an investigation of the mechanism of cellular sensitivity and resistance. Three murine leukemia L1210 cell lines will be used: a) L1210/0, which is sensitive to the action of both cis-diamminedichloroplatinum(II) (cis-DDP) and 1,2- diaminocyclohexaneplatinum (DACH-Pt) analogues, b) L1210/DDP, which is preferentially resistant to cis-DDP, c) L1210/DACH, which is preferentially resistant to DACH-Pt. The resistant cells exhibit some reduced accumulation of cis-DDP, but the majority of resistance is attributed to enhanced DNA repair. Two different assays of DNA repair have been used, one measuring direct removal of DNA bound adducts, the other measuring the ability of cells to express a transfected damaged gene. The latter assay demonstrated that one adduct was normally sufficient to inhibit transcription, suggesting this could contribute to the mechanism of toxicity rather than inhibition of DNA synthesis previously suggested.
The aims are, therefore, to further characterize the DNA repair process. using DNA repair inhibitors and probe for repair of specific genes. Attempts will be made to purify the protein(s) involved. An assay for inhibition of transcription on a defined gene is proposed, which will be compared to DNA repair of adducts within the same gene. Recombination, as a mechanism for replicative bypass of DNA adducts will also be investigated. In other experiments, attempts will be made to identify the chromosome(s) coding for resistance by using chromosome-mediated gene transfer. This is a preliminary to isolating the genes in- volved. Parallel studies will be performed to assess the mechanism of resistance to DACH-Pt in L1210/DACH and also to assess the mechanisms of hypersensitivity to cis-DDP in embryonal cells. These cells are representative of tumors that are very responsive to cis- DDP therapy.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA036039-08
Application #
3173546
Study Section
Experimental Therapeutics Subcommittee 1 (ET)
Project Start
1983-06-01
Project End
1990-12-31
Budget Start
1990-01-01
Budget End
1990-12-31
Support Year
8
Fiscal Year
1990
Total Cost
Indirect Cost
Name
Dartmouth College
Department
Type
Schools of Arts and Sciences
DUNS #
041027822
City
Hanover
State
NH
Country
United States
Zip Code
03755
Kroning, R; Jones, J A; Hom, D K et al. (1995) Enhancement of drug sensitivity of human malignancies by epidermal growth factor. Br J Cancer 72:615-9
Eastman, A; Barry, M A (1992) The origins of DNA breaks: a consequence of DNA damage, DNA repair, or apoptosis? Cancer Invest 10:229-40
Jennerwein, M M; Eastman, A; Khokhar, A R (1991) The role of DNA repair in resistance of L1210 cells to isomeric 1,2-diaminocyclohexaneplatinum complexes and ultraviolet irradiation. Mutat Res 254:89-96
Eastman, A (1991) Analysis and quantitation of the DNA damage produced in cells by the cisplatin analog cis-[3H]dichloro(ethylenediamine)platinum (II). Anal Biochem 197:311-5
Sheibani, N; Eastman, A (1990) Analysis of various mRNA potentially involved in cisplatin resistance of murine leukemia L1210 cells. Cancer Lett 52:179-85
Barry, M A; Behnke, C A; Eastman, A (1990) Activation of programmed cell death (apoptosis) by cisplatin, other anticancer drugs, toxins and hyperthermia. Biochem Pharmacol 40:2353-62
Sorenson, C M; Barry, M A; Eastman, A (1990) Analysis of events associated with cell cycle arrest at G2 phase and cell death induced by cisplatin. J Natl Cancer Inst 82:749-55
Jennerwein, M M; Eastman, A; Khokhar, A (1989) Characterization of adducts produced in DNA by isomeric 1,2-diaminocyclohexaneplatinum(II) complexes. Chem Biol Interact 70:39-49
Sheibani, N; Jennerwein, M M; Eastman, A (1989) DNA repair in cells sensitive and resistant to cis-diamminedichloroplatinum(II): host cell reactivation of damaged plasmid DNA. Biochemistry 28:3120-4
Sorenson, C M; Eastman, A (1988) Influence of cis-diamminedichloroplatinum(II) on DNA synthesis and cell cycle progression in excision repair proficient and deficient Chinese hamster ovary cells. Cancer Res 48:6703-7

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