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Nuklearmedizin 2012; 51(05): 163-169
DOI: 10.3413/Nukmed-0459-12-01
Original article
Schattauer GmbH

18F-FLT and 125I-IdUrd uptake increase in human tumour cell lines induced by the thymidylate synthase inhibitor FdUrd

Original articleDer Thymidin synthaseinhibitor FdUrd induziert in humanen Tumorzelllinien einen Anstieg im Uptake von 18F-FLT und 125I-IdUrd
D. Viertl
1   Department of Nuclear Medicine, University Hospital of Lausanne, Switzerland
,
F. Perillo-Adamer
2   Department of Radio- Oncology, University Hospital of Lausanne, Switzerland
,
P.-A. André
1   Department of Nuclear Medicine, University Hospital of Lausanne, Switzerland
,
S. M. Ametamey
3   Center for Radiopharmaceutical Science, Swiss Federal Institute of Technology of Zurich, Switzerland
,
T. L. Ross
3   Center for Radiopharmaceutical Science, Swiss Federal Institute of Technology of Zurich, Switzerland
,
M. Kosinski
1   Department of Nuclear Medicine, University Hospital of Lausanne, Switzerland
,
Y. M. Dupertuis
4   Unit of Nutrition, University Hospital of Geneva, Switzerland
,
A. Bischof Delaloye
1   Department of Nuclear Medicine, University Hospital of Lausanne, Switzerland
,
F. Buchegger
1   Department of Nuclear Medicine, University Hospital of Lausanne, Switzerland
5   Department of Nuclear Medicine, University Hospital of Geneva, Switzerland
› Author Affiliations
Further Information

Publication History

received: 05 January 2012

accepted in revised form: 30 April 2012

Publication Date:
02 January 2018 (online)

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Summary

Aim: 5-fluoro-2′-deoxyuridine (FdUrd) depletes the endogenous 5′-deoxythymidine triphosphate (dTTP) pool. We hypothesized whether uptake of exogenous dThd analogues could be favoured through a feedback enhanced salvage pathway and studied the FdUrd effect on cellular uptake of 3′-deoxy-3′-18F-fluorothymidine (18F-FLT) and 5-125I-iodo-2′-deoxyuridine (125I-IdUrd) in different cancer cell lines in parallel. Methods: Cell uptake of 18F-FLT and 125I-IdUrd was studied in 2 human breast, 2 colon cancer and 2 glioblastoma lines. Cells were incubated with/without 1 μmol/l FdUrd for 1 h and, after washing, with 1.2 MBq 18F-FLT or 125I-IdUrd for 0.3 to 2 h. Cell bound 18F-FLT and 125I-IdUrd was counted and expressed in % incubated activity (%IA). Kinetics of 18F-FLT cell uptake and release were studied with/without FdUrd modulation. 2′-3H-methyl-fluorothymidine (2′-3H-FLT) uptake with/without FdUrd pretreatment was tested on U87 spheroids and monolayer cells. Results: Basal uptake at 2 h of 18F-FLT and 125I-IdUrd was in the range of 0.8–1.0 and 0.4–0.6 Bq/cell, respectively. FdUrd pretreatment enhanced 18F-FLT and 125I-IdUrd uptake 1.2–2.1 and 1.7–4.4 fold, respectively, while co-incubation with excess thymidine abrogated all 18F-FLT uptake. FdUrd enhanced 18F-FLT cellular inflow in 2 breast cancer lines by factors of 1.8 and 1.6, respectively, while outflow persisted at a slightly lower rate. 2′-3H-FLT basal uptake was very low while uptake increase after FdUrd was similar in U87 monolayer cells and spheroids. Conclusions: Basal uptake of 18F-FLT was frequently higher than that of 125I-IdUrd but FdUrd induced uptake enhancement was stronger for 125I-IdUrd in five of six cell lines. 18F-FLT outflow from cells might be an explanation for the observed difference with 125I-IdUrd.

Zusammenfassung

Ziel: 5-Fluor-2′-deoxyuridin (FdUrd) bewirkt eine Entleerung des endogenen 5′-Deoxythymidintriphosphat(dTTP)-Pools. Wir prüften unsere Hypothese nach der die Aufnahme von exogener Thymidin(dThd)-Analoga infolge des Rückkopplungs-gesteuerten Salvage-Stoffwechsels erhöht ist. Dazu verglichen wir bei verschiedenen Krebszelllinien den Effekt von FdUrd auf die Zellaufnahme von 3′-Deoxy-3′-18F-fluorthymidin (18F-FLT) mit dem von 5-125I-Iod-2′-deoxyuridin (125I-IdUrd). Methoden: Die 18F-FLT- und 125I-IdUrd-Aufnahme wurde in je zwei humanen Brustkrebsen, Kolonkarzinomen und Glioblastomen studiert. Die Zellen wurden mit bzw. ohne 1 μmol/l FdUrd für 1 h vorbehandelt und nach Waschen mit 1,2 MBq 18F-FLT bzw. 125I-IdUrd für 0,3 bis 2 h inkubiert. Zellgebundenes 18F-FLT und 125I-IdUrd wurden gemessen und in % der inkubierten Aktivität (%IA) ausgedrückt. Die Kinetik der zellulären Aufnahme und Abgabe von 18F-FLT wurde mit und ohne FdUrd-Modulation gemessen. Die Aufnahme von 2′-3H-Methylfluorthymidin (2′-3H-FLT) mit und ohne FdUrd-Vorbehandlung wurde in U87-Spheroïden und Monolayer-Zellen verglichen. Ergebnisse: Nach 2 h lag die basale Aufnahme von 18F-FLT bei 0,8–1,0 Bq/Zelle und die von 125I-IdUrd bei 0,4–0,6 Bq/Zelle. FdUrd- Vorbehandlung erhöhte die Aufnahme von 18F-FLT um den Faktor 1,2 bis 2,1 und die von 125I-IdUrd um das 1,7- bis 4,4-Fache. Koinkubation mit einem Thymidinüberschuss verhinderte die Aufnahme von 18F-FLT völlig. FdUrd erhöhte die zelluläre Aufnahme von 18F-FLT in den beiden Brustkrebszelllinien um den Faktor 1,8 bzw. 1,6, während der Ausfluss auf geringfügig niedrigerem Niveau anhielt. Die basale Aufnahme vom 2′-3H-FLT war sehr niedrig und die Aufnahmesteigerung nach FdUrd war in U87-Monolayer-Zellen und Spheroiden ähnlich. Schlussfolgerung: Die basal gemessene Aufnahme von 18F-FLT in Zellen war meist höher als die von 125I-IdUrd, aber die FdUrdinduzierte Aufnahmesteigerung war für 125I-IdUrd bei fünf von sechs Zelllinien stärker. Als Erklärung für den beobachteten Unterschied zwischen 18F-FLT und 125I-IdUrd kommt der zelluläre Ausfluss von 18F-FLT in Betracht.

Keywords

18F-FLT - 125I-IdUrd - FdUrd - in vitro - cell uptake modulation

Schlüsselwörter

18F-FLT - 125I-IdUrd - FdUrd - in vitro - Modulation der Zellaufnahme
 

  • References

  • 1 Brockenbrogh JS, Souquet T, Morihara JK. et al. Tumor 3'-deoxy-3'-18F-fluorothymidine (18F-FLT) uptake by PET correlates with thymidine kinase 1 expression: static and kinetic analysis of 18F-FLT PET studies in lung tumors. J Nucl Med 2011; 52: 1181-1188.
    CrossrefPubMedGoogle Scholar
  • 2 Buchegger F, Perillo-Adamer F, Dupertuis YM. et al. Auger radiation targeted into DNA: a therapy perspective. Eur J Nucl Med Mol Imaging 2006; 33: 1352-1363.
    CrossrefPubMedGoogle Scholar
  • 3 Cheng YC, Nakayama K. Effects of 5-fluoro-2'-deoxyuridine on DNA metabolism in HeLa cells. Mol Pharmacol 1983; 23: 171-174.
    PubMedGoogle Scholar
  • 4 Commerford SL. Biological stability of 5-iodo-2'-deoxyuridine labelled with iodine-125 after its incorporation into the deoxyribonucleic acid of the mouse. Nature 1965; 206: 949-950.
    CrossrefPubMedGoogle Scholar
  • 5 Foulon CF, Adelstein SJ, Kassis AI. Kit formulation for the preparation of radiolabeled iododeoxyuridine by demetallation. J Nucl Med 1996; 37 (Suppl. 04) 1S-3S.
    PubMedGoogle Scholar
  • 6 Grierson JR, Schwartz JL, Muzi M. et al. Metabolism of 3'-deoxy-3'-[18F]fluorothymidine in proliferating A549 cells: validations for positron emission tomography. Nucl Med Biol 2004; 31: 829-837.
    CrossrefPubMedGoogle Scholar
  • 7 Kassis AI, Sastry KS, Adelstein SJ. Kinetics of uptake, retention, and radiotoxicity of 125IUdR in mammalian cells: implications of localized energy deposition by Auger processes. Radiat Res 1987; 109: 78-89.
    CrossrefPubMedGoogle Scholar
  • 8 Kim DW, Ahn DS, Oh YH. et al. A new class of SN2 reactions catalyzed by protic solvents: Facile fluorination for isotopic labeling of diagnostic molecules. J Am Chem Soc 2006; 128: 16394-16397.
    CrossrefPubMedGoogle Scholar
  • 9 Lawrence TS, Davis MA, McKeever PE. et al. Fluorodeoxyuridine-mediated modulation of iododeoxyuridine incorporation and radiosensitization in human colon cancer cells in vitro and in vivo. Cancer Res 1991; 51: 3900-3905.
    PubMedGoogle Scholar
  • 10 Lawrence TS, Davis MA, Tang HY. et al. Fluorodeoxyuridine-mediated cytotoxicity and radiosensitization require S phase progression. Int J Radiat Biol 1996; 70: 273-280.
    CrossrefPubMedGoogle Scholar
  • 11 McGinn CJ, Miller EM, Lindstrom MJ. et al. The role of cell cycle redistribution in radiosensitization: implications regarding the mechanism of fluorodeoxyuridine radiosensitization. Int J Radiat Oncol Biol Phys 1994; 30: 851-859.
    CrossrefPubMedGoogle Scholar
  • 12 Paproski RJ, Ng AM, Yao SY. et al. The role of human nucleoside transporters in uptake of 3'-deoxy-3'-fluorothymidine. Mol Pharmacol 2008; 74: 1372-1380.
    CrossrefPubMedGoogle Scholar
  • 13 Perillo-Adamer F, Bischof Delaloye A, Genton CS. et al. Short fluorodeoxyuridine exposure of different human glioblastoma lines induces high-level accumulation of S-phase cells that avidly incorporate 125I-iododeoxyuridine. Eur J Nucl Med Mol Imaging 2006; 33: 613-620.
    CrossrefPubMedGoogle Scholar
  • 14 Schaffland AO, Bischof Delaloye A, Kosinski M. et al. The preparation of clinical grade 5-[123I]iodo-2'-deoxyuridine and 5-[125I]iodo-2'-deoxyuridine with high in vitro stability and the potential for early proliferation scintigraphy. Nucl Med Commun 2004; 25: 461-468.
    CrossrefPubMedGoogle Scholar
  • 15 Shields AF, Grierson JR, Dohmen BM. et al. Imaging proliferation in vivo with [18F]FLT and positron emission tomography. Nat Med 1998; 4: 1334-1336.
    CrossrefPubMedGoogle Scholar
  • 16 Shields AF. Positron emission tomography measurement of tumor metabolism and growth: its expanding role in oncology. Mol Imaging Biol 2006; 8: 141-150.
    CrossrefPubMedGoogle Scholar
  • 17 Sinigaglia F, Talmadge KW. Inhibition of [3H]thymidine incorporation by Mycoplasma arginini-infected cells due to enzymatic cleavage of the nucleoside. Eur J Immunol 1985; 15: 692-696.
    CrossrefPubMedGoogle Scholar
  • 18 Viertl D, Bischof Delaloye A, Lanz B. et al. Increase of [18F]FLT tumor uptake in vivo mediated by FdUrd: Toward improving cell proliferation positron emission tomography. Mol Imaging Biol 2011; 13: 321-331
    CrossrefPubMedGoogle Scholar