TY - JOUR
T1 - DNA repair mechanisms involved in gemcitabine cytotoxicity and in the interaction between gemcitabine and cisplatin
AU - Crul, Mirjam
AU - Van Waardenburg, R. C A M
AU - Bocxe, Suzanne
AU - Van Eijndhoven, M. A J
AU - Pluim, Dick
AU - Beijnen, Jos H.
AU - Schellens, J. H M
PY - 2003/1/15
Y1 - 2003/1/15
N2 - The influence of DNA repair mechanisms on the interaction between gemcitabine and cisplatin was studied using a panel of Chinese hamster ovary (CHO) cell lines each deficient in one of the following repair pathways: base excision repair (BER), nucleotide excision repair (NER), homologous recombination (HR) and non-homologous end joining (NHEJ). NER and HR are known to be involved in platinum-DNA adduct repair. Single agent experiments demonstrated that each of the repair deficient cell lines had a similar sensitivity towards gemcitabine as the parental cell lines, whereas the NER- and HR-deficient lines showed increased sensitivity towards cisplatin. Furthermore, in the parental cell lines, the administration sequence cisplatin followed by gemcitabine was synergistic, whereas the reversed schedule showed additivity and simultaneous administration revealed antagonistic cytotoxicity. In the repair deficient cell lines, using this synergistic schedule of cisplatin followed by gemcitabine, loss of synergy was observed in the NER- and HR-deficient cell lines. However, the magnitude of the effect in the NER-deficient cells was small. The sensitivity to the combination of cisplatin and gemcitabine shown by the BER- and NHEJ-deficient cell lines did not differ significantly from that of the parental cell line. Cellular accumulation of platinum as well as the formation of GG- and AG-intrastrand adducts in the parental line and in the HR-deficient line were not affected by gemcitabine. In conclusion, our results indicate that BER, NER, HR, and NHEJ are most likely incapable of modulating the cytotoxicity of gemcitabine, and that HR is involved in the synergistic interaction between cisplatin and gemcitabine in our cell system.
AB - The influence of DNA repair mechanisms on the interaction between gemcitabine and cisplatin was studied using a panel of Chinese hamster ovary (CHO) cell lines each deficient in one of the following repair pathways: base excision repair (BER), nucleotide excision repair (NER), homologous recombination (HR) and non-homologous end joining (NHEJ). NER and HR are known to be involved in platinum-DNA adduct repair. Single agent experiments demonstrated that each of the repair deficient cell lines had a similar sensitivity towards gemcitabine as the parental cell lines, whereas the NER- and HR-deficient lines showed increased sensitivity towards cisplatin. Furthermore, in the parental cell lines, the administration sequence cisplatin followed by gemcitabine was synergistic, whereas the reversed schedule showed additivity and simultaneous administration revealed antagonistic cytotoxicity. In the repair deficient cell lines, using this synergistic schedule of cisplatin followed by gemcitabine, loss of synergy was observed in the NER- and HR-deficient cell lines. However, the magnitude of the effect in the NER-deficient cells was small. The sensitivity to the combination of cisplatin and gemcitabine shown by the BER- and NHEJ-deficient cell lines did not differ significantly from that of the parental cell line. Cellular accumulation of platinum as well as the formation of GG- and AG-intrastrand adducts in the parental line and in the HR-deficient line were not affected by gemcitabine. In conclusion, our results indicate that BER, NER, HR, and NHEJ are most likely incapable of modulating the cytotoxicity of gemcitabine, and that HR is involved in the synergistic interaction between cisplatin and gemcitabine in our cell system.
KW - Cisplatin
KW - DNA repair
KW - Gemcitabine
KW - Interaction
UR - http://www.scopus.com/inward/record.url?scp=0037437791&partnerID=8YFLogxK
U2 - https://doi.org/10.1016/S0006-2952(02)01508-3
DO - https://doi.org/10.1016/S0006-2952(02)01508-3
M3 - Article
C2 - 12504803
SN - 0006-2952
VL - 65
SP - 275
EP - 282
JO - Biochemical pharmacology
JF - Biochemical pharmacology
IS - 2
ER -