Open AccessElevated expression of thymidylate synthase cycle genes in cisplatin-resistant human ovarian carcinoma A2780 cells.
Author(s) -
Kevin J. Scanlon,
Mohammed KashaniSabet
Publication year - 1988
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.85.3.650
Subject(s) - thymidylate synthase , dihydrofolate reductase , cisplatin , microbiology and biotechnology , biology , methyltransferase , enzyme , biochemistry , gene , genetics , fluorouracil , cancer , methylation , chemotherapy
Activity of the thymidylate synthase cycle was compared in the human ovarian carcinoma cell line A2780 and a subline that is resistant to cisplatin by a factor of 3. Resistant cells exhibited a 3-fold increase in mRNA for both dihydrofolate reductase (5,6,7,8-tetrahydrofolate:NADP+-oxidoreductase, EC 1.5.1.3) and thymidylate synthase (5,10-methylenetetrahydrofolate:dUMP C-methyltransferase, EC 2.1.1.45) when compared with the parent line. Resistance to cisplatin also resulted in a 2.5-fold increase in enzyme activity for dihydrofolate reductase and thymidylate synthase; however, this increase did not result from amplification of the genes for these two enzymes. These data suggest that the initial step of cisplatin resistance in A2780 cells is a consequence of enhanced expression of the thymidylate synthase cycle.