» Articles » PMID: 1319727

Mechanisms of Collateral Sensitivity to Fluorouracil of a Cis-diamminedichloroplatinum(II)-resistant Human Non-small Lung Cancer Cell Line

Overview
Journal Br J Cancer
Specialty Oncology
Date 1992 Jun 1
PMID 1319727
Authors
Affiliations
Soon will be listed here.
Abstract

A cisplatin(CDDP)-resistant subline of a human lung cancer cell line, PC-7/CDDP, was 4.7-fold more resistant to CDDP than the parent line in a colony-forming assay. The sensitivity of this cell line to anthracyclines, vinca-alkaloid, etoposide, mitomycin C, and bleomycin was similar to that of the parental line, PC-7. However, PC-7/CDDP exhibited 4-fold higher sensitivity to fluorouracil (FUra). Possible mechanisms associated with the collateral sensitivity to FUra were studied in PC-7/CDDP cells. The sensitivity of both cell lines to FUra did not correlate with the effect of FUra on RNA. On the other hand, FUra induced a greater reduction in dTTP pools and more single strand breaks in PC-7/CDDP than in PC-7 cells. These results suggest that the pathway for de novo deoxyribonucleotide synthesis may be a target for FUra in PC-7/CDDP cells. However, inhibition of thymidylate synthase after FUra treatment did not correlate with the DNA-directed activity of FUra. Based on the above findings, the decreased salvage synthesis of dTTP was considered a possible mechanism of the greater reduction of dTTP pools in PC-7/CDDP cells. However, the activity of dThd kinase was the same in both cell lines. In the presence of physiological concentrations of exogenous dThd in the serum, uptake of dThd was less in PC-7/CDDP cells than that in PC-7 cells. Our data suggest that FUra-induced cytotoxicity in PC-7/CDDP cells is associated with the inhibition of dTTP synthesis and that the decreased uptake of dThd is a possible mechanism of the collateral sensitivity to FUra in PC-7/CDDP cells.

References
1.
Kohn K, Erickson L, Ewig R, Friedman C . Fractionation of DNA from mammalian cells by alkaline elution. Biochemistry. 1976; 15(21):4629-37. DOI: 10.1021/bi00666a013. View

2.
Tanaka K, Yoshioka A, Tanaka S, Wataya Y . An improved method for the quantitative determination of deoxyribonucleoside triphosphates in cell extracts. Anal Biochem. 1984; 139(1):35-41. DOI: 10.1016/0003-2697(84)90386-5. View

3.
Nottebrock H, Then R . Thymidine concentrations in serum and urine of different animal species and man. Biochem Pharmacol. 1977; 26(22):2175-9. DOI: 10.1016/0006-2952(77)90271-4. View

4.
Fujiwara Y, Sugimoto Y, Kasahara K, Bungo M, Yamakido M, Tew K . Determinants of drug response in a cisplatin-resistant human lung cancer cell line. Jpn J Cancer Res. 1990; 81(5):527-35. PMC: 5918066. DOI: 10.1111/j.1349-7006.1990.tb02602.x. View

5.
Bungo M, Fujiwara Y, Kasahara K, Nakagawa K, Ohe Y, Sasaki Y . Decreased accumulation as a mechanism of resistance to cis-diamminedichloroplatinum(II) in human non-small cell lung cancer cell lines: relation to DNA damage and repair. Cancer Res. 1990; 50(9):2549-53. View