Pharmacology of Selective Antitumor Action/Antifols

Sirotnak, Francis M.

Abstract

The applicants overall approach to improvement in antifolate-based cancer treatment has been to seek detailed understanding in tumor and normal proliferative tissues that are the site of limiting toxicity of membrane transport, cellular pharmacokinetics and metabolic and enzymologic factors which govern antifolate action and determine therapeutic selectivity. Further advancement of this goal will be sought as follows. 1. Studies on folylpolyglutamyl synthetase. In light of our evidence documenting a role for FPGS in selective antitumor action and acquired resistance to 4- aminofolates; (a) Strategies will be utilized for obtaining additional tumor cell variants that overproduce FPGS and for deriving anti-FPGS monoclonal antibodies to be used to purify FPGS from these variants for biochemical and other studies described below; (b) Biochemical and genetic characterization of antifolate resistant tumor cell variants underproducing or overproducing FPGS will be carried out utilizing immunologic, cytogenetic and cell-cell hybridization methodology, (c) Relative content and regulation of this enzyme property in parental tumor cells and resistant variants with altered FPGS levels and in normal proliferative tissue will be examined in the context of proliferative state, growth arrest and differentiation. 2. Studies on folypolyglutamyl hydrolase (FPGH). As a continuation of earlier pharmacologic studies, we will attempt further purification of tumor-derived and cellular localization will be sought: 3. Metabolic turnover of 4-aminofolylpolyglutamates. We will continue our studies of lysosomal mediated hydrolysis of 4- aminofolylpolyglutamates focusing as well on the mechanism of lysomal internalization: 4. Studies on folate metabolism related to experimental therapeutic with antifolates and fluoropyrimidines. Work will be continued on the perturbations of reduced pools in tumor cells and normal proliferative tissues of antifolate treated mice. These will be extended to include studies of the metabolic disposition of Ca leucovorin and the role of 5,10-methenylTHF synthetase.

Funding Agency

• Agency: National Institute of Health (NIH)
• Institute: National Cancer Institute (NCI)
• Type: Research Project (R01)
• Project #: 5R01CA022764-16
• Application #: 3165925
• Study Section: Experimental Therapeutics Subcommittee 1 (ET)
• Project Start: 1978-02-01
• Project End: 1994-01-31
• Budget Start: 1993-02-01
• Budget End: 1994-01-31
• Support Year: 16
• Fiscal Year: 1993

Institution

• Name: Sloan-Kettering Institute for Cancer Research
• DUNS #: 064931884
• City: New York
• State: NY
• Country: United States
• Zip Code: 10065

Publications

Piper, J R; Ramamurthy, B; Johnson, C A et al. (1996) Analogues of 10-deazaaminopterin and 5-alkyl-5,10-dideazaaminopterin with the 4-substituted 1-naphthoyl group in the place of 4-substituted benzoyl. J Med Chem 39:614-8

Egan, M G; Sirlin, S; Rumberger, B G et al. (1995) Rapid decline in folylpolyglutamate synthetase activity and gene expression during maturation of HL-60 cells. Nature of the effect, impact on folate compound polyglutamate pools, and evidence for programmed down-regulation during maturation. J Biol Chem 270:5462-8

Bunni, M A; Sirotnak, F M; Otter, G M et al. (1994) Disposition of leucovorin and its metabolites in the plasma, intestinal epithelium, and intraperitoneal L1210 cells of methotrexate-pretreated mice. Cancer Chemother Pharmacol 34:455-8

Schlemmer, S R; Sirotnak, F M (1993) Retentiveness of methotrexate polyglutamates in cultured L1210 cells. Evidence against a role for mediated plasma membrane transport outward. Biochem Pharmacol 45:1261-6

Piper, J R; Johnson, C A; Otter, G M et al. (1992) Synthesis and antifolate evaluation of 10-ethyl-5-methyl-5,10- dideazaaminopterin and an alternative synthesis of 10-ethyl-10- deazaaminopterin (edatrexate). J Med Chem 35:3002-6

Barrueco, J R; O'Leary, D F; Sirotnak, F M (1992) Metabolic turnover of methotrexate polyglutamates in lysosomes derived from S180 cells. Definition of a two-step process limited by mediated lysosomal permeation of polyglutamates and activating reduced sulfhydryl compounds. J Biol Chem 267:15356-61

Piper, J R; Malik, N D; Rhee, M S et al. (1992) Synthesis and antifolate evaluation of the 10-propargyl derivatives of 5-deazafolic acid, 5-deazaaminopterin, and 5-methyl-5-deazaaminopterin. J Med Chem 35:332-7

Barrueco, J R; Sirotnak, F M (1991) Evidence for the facilitated transport of methotrexate polyglutamates into lysosomes derived from S180 cells. Basic properties and specificity for polyglutamate chain length. J Biol Chem 266:11732-7

Rumberger, B G; Barrueco, J R; Sirotnak, F M (1990) Differing specificities for 4-aminofolate analogues of folylpolyglutamyl synthetase from tumors and proliferative intestinal epithelium of the mouse with significance for selective antitumor action. Cancer Res 50:4639-43

Rumberger, B G; Schmid, F A; Otter, G M et al. (1990) Preferential selection during therapy in vivo by edatrexate compared to methotrexate of resistant L1210 cell variants with decreased folylpolyglutamate synthetase activity. Cancer Commun 2:305-10