Effects of Motexafin gadolinium on tumor metabolism and radiation sensitivity Journal Article


Authors: Xu, S.; Zakian, K.; Thaler, H.; Matei, C.; Alfieri, A.; Chen, Y.; Koutcher, J. A.
Article Title: Effects of Motexafin gadolinium on tumor metabolism and radiation sensitivity
Abstract: Purpose: Experiments were undertaken to determine if metabolic changes induced by Motexafin gadolinium (Gd-Tex+2, XCYTRIN) predict time intervals between drug and radiation wherein there is enhancement of radiation efficacy. Methods and Materials: We evaluated the effect of Gd-Tex+2 on tumor metabolism and on tumor growth using a mouse mammary carcinoma model and 31P nuclear magnetic resonance (NMR) experiments. Response to therapy was evaluated based on time for the tumor to regrow to pretreatment size and also tumor doubling time. Results: 31P NMR experiments indicated that Gd-Tex+2 effected tumor energy metabolism during the first 24 hours postadministration. A decrease in phosphocreatine was noted at 2 (p < 0.04), 6 (p < 0.006), and 24 (p < 0.001) hours post Gd-Tex+2. A decrease in nucleoside triphosphates was noted only at 2 hours (p < 0.02), with subsequent recovery at 6 hours. Phosphocreatine in control (saline treated) tumors showed a significant decrease only at 24 hours (p < 0.01). Irradiation at 2 and 6 hours post Gd-Tex+2 induced an enhanced effect compared to radiation alone as measured by analyzing the growth curves, maximum tumor volumes, and the time for the tumors to regrow to their initial volumes. Irradiation at 24 hours post Gd-Tex+2 induced a modest enhancement in tumor growth delay compared to radiation alone. Discussion: NMR spectroscopy may be useful for monitoring tumor metabolism after treatment with Gd-Tex+2 and administering radiation during the time of maximal efficacy of Gd-Tex+2. Copyright © 2001 Elsevier Science Inc.
Keywords: controlled study; unclassified drug; nonhuman; conference paper; cancer radiotherapy; gadolinium; monitoring; mouse; metabolism; animals; mice; radiation; animal experiment; animal model; time; time factors; tumors; breast carcinoma; cancer size; magnetic resonance spectroscopy; radiosensitivity; tumor growth; tumor; radiosensitizing agent; phosphorus nuclear magnetic resonance; energy metabolism; phosphates; nuclear magnetic resonance; gadolinium texaphyrin; phosphorus; mice, inbred c3h; radiobiology; radiation tolerance; nmr; mammary neoplasms, animal; dose time effect relation; creatine phosphate; nucleoside triphosphate; tumor metabolism; drug dosage; cancer graft; photosensitizing agents; metalloporphyrins; male; priority journal; motexafin gadolinium; radiosensitizer; radiation efficacy
Journal Title: International Journal of Radiation Oncology, Biology, Physics
Volume: 49
Issue: 5
ISSN: 0360-3016
Publisher: Elsevier Inc.  
Date Published: 2001-04-01
Start Page: 1381
End Page: 1390
Language: English
DOI: 10.1016/s0360-3016(00)01566-2
PUBMED: 11286846
PROVIDER: scopus
DOI/URL:
Notes: Export Date: 21 May 2015 -- Source: Scopus
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MSK Authors
  1. Kristen L Zakian
    82 Zakian
  2. Jason A Koutcher
    278 Koutcher
  3. Howard T Thaler
    245 Thaler
  4. Cornelia Matei
    35 Matei
  5. Su Xu
    27 Xu