PURPOSE: Fluoropyrimidines like 1-(2'-deoxy-2'-fluoro-beta-D: -arabinofuranosyl)-thymine (FMAU) and 3'-deoxy-3'-fluorothymidine (FLT) accumulate in tumors and are being used as positron emission tomography tumor-imaging tracers. Proliferating tissues with high thymidine kinase 1 (TK1) activity retain FLT; however, the mechanism of selective accumulation of FMAU in tumors and certain other tissues requires further study. METHODS: Retention of [(3)H]FLT and [(3)H]FMAU was measured in prostate cancer cell lines PC3, LNCaP, DU145, and the breast cancer cell line MD-MBA-231, and the tracer metabolites were analyzed by high-performance liquid chromatography (HPLC). FMAU retention, thymidine kinase 2 (TK2) activity, and mitochondrial mass were determined in cells stressed by depleted cell culture medium or by treating with oxidative, reductive, and energy stress, or specific adenosine monophosphate-activated protein kinase activator, or eIF2 inhibitor. TK1 and TK2 activities and mitochondrial mass were determined by FLT phosphorylation, 1-beta-D: -arabinofuranosylthymine (Ara-T) phosphorylation, and flow cytometry, respectively. RESULTS: FMAU retention in rapidly proliferating cancer cell lines was five to ten times lower than FLT after 10 min incubation. HPLC analysis of the cellular extracts showed that phosphorylated tracers are the main retained metabolites. Nutritional stress decreased TK1 activity and FLT retention but increased retained FMAU. TK2 inhibition decreased FMAU retention and phosphorylation with negligible effects on FLT. Oxidative, reductive, or energy stress increased FMAU retention and correlated with mitochondrial mass (r (2) = 0.88, p = 0.006). FMAU phosphorylation correlated with increased TK2 activity (r (2) = 0.87, p = 0.0002). CONCLUSION: FMAU is preferably phosphorylated by TK2 and can track TK2 activity and mitochondrial mass in cellular stress. FMAU may provide an early marker of treatment effects.
PURPOSE:Fluoropyrimidines like 1-(2'-deoxy-2'-fluoro-beta-D: -arabinofuranosyl)-thymine (FMAU) and 3'-deoxy-3'-fluorothymidine (FLT) accumulate in tumors and are being used as positron emission tomography tumor-imaging tracers. Proliferating tissues with high thymidine kinase 1 (TK1) activity retain FLT; however, the mechanism of selective accumulation of FMAU in tumors and certain other tissues requires further study. METHODS: Retention of [(3)H]FLT and [(3)H]FMAU was measured in prostate cancer cell lines PC3, LNCaP, DU145, and the breast cancer cell line MD-MBA-231, and the tracer metabolites were analyzed by high-performance liquid chromatography (HPLC). FMAU retention, thymidine kinase 2 (TK2) activity, and mitochondrial mass were determined in cells stressed by depleted cell culture medium or by treating with oxidative, reductive, and energy stress, or specific adenosine monophosphate-activated protein kinase activator, or eIF2 inhibitor. TK1 and TK2 activities and mitochondrial mass were determined by FLT phosphorylation, 1-beta-D: -arabinofuranosylthymine (Ara-T) phosphorylation, and flow cytometry, respectively. RESULTS: FMAU retention in rapidly proliferating cancer cell lines was five to ten times lower than FLT after 10 min incubation. HPLC analysis of the cellular extracts showed that phosphorylated tracers are the main retained metabolites. Nutritional stress decreased TK1 activity and FLT retention but increased retained FMAU. TK2 inhibition decreased FMAU retention and phosphorylation with negligible effects on FLT. Oxidative, reductive, or energy stress increased FMAU retention and correlated with mitochondrial mass (r (2) = 0.88, p = 0.006). FMAU phosphorylation correlated with increased TK2 activity (r (2) = 0.87, p = 0.0002). CONCLUSION: FMAU is preferably phosphorylated by TK2 and can track TK2 activity and mitochondrial mass in cellular stress. FMAU may provide an early marker of treatment effects.
Authors: James R Bading; Antranik H Shahinian; Amy Vail; Pravin Bathija; G W Koszalka; Robert T Koda; Mian M Alauddin; John D Fissekis; Peter S Conti Journal: Nucl Med Biol Date: 2004-05 Impact factor: 2.408
Authors: Jérôme Kluza; Philippe Marchetti; Miguel-Angel Gallego; Steve Lancel; Charles Fournier; Anne Loyens; Jean-Claude Beauvillain; Christian Bailly Journal: Oncogene Date: 2004-09-16 Impact factor: 9.867
Authors: Galina Polekhina; Abhilasha Gupta; Belinda J Michell; Bryce van Denderen; Sid Murthy; Susanne C Feil; Ian G Jennings; Duncan J Campbell; Lee A Witters; Michael W Parker; Bruce E Kemp; David Stapleton Journal: Curr Biol Date: 2003-05-13 Impact factor: 10.834
Authors: Omid S Tehrani; Otto Muzik; Lance K Heilbrun; Kirk A Douglas; Jawana M Lawhorn-Crews; Haihao Sun; Thomas J Mangner; Anthony F Shields Journal: J Nucl Med Date: 2007-09 Impact factor: 10.057
Authors: David A Plotnik; Lindsay E Emerick; Kenneth A Krohn; Jashvant D Unadkat; Jeffrey L Schwartz Journal: J Nucl Med Date: 2010-08-18 Impact factor: 10.057
Authors: Jason T Lee; Hanwen Zhang; Maxim A Moroz; Yury Likar; Larissa Shenker; Nikita Sumzin; Jose Lobo; Juan Zurita; Jeffrey Collins; R Michael van Dam; Vladimir Ponomarev Journal: Mol Imaging Biol Date: 2017-02 Impact factor: 3.488
Authors: Christopher I McHugh; Monica R Thipparthi; Jawana M Lawhorn-Crews; Lisa Polin; Shirish Gadgeel; Janice Akoury; Thomas J Mangner; Kirk A Douglas; Jing Li; Manohar Ratnam; Anthony F Shields Journal: J Nucl Med Date: 2018-04-19 Impact factor: 10.057
Authors: Ulka N Vaishampayan; Izabela Podgorski; Lance K Heilbrun; Jawana M Lawhorn-Crews; Kimberlee C Dobson; Julie Boerner; Karri Stark; Daryn W Smith; Elisabeth I Heath; Joseph A Fontana; Anthony F Shields Journal: Clin Cancer Res Date: 2018-10-16 Impact factor: 12.531