We previously reported that fluorouracil (5FU) accumulation and metabolism in human livers and tumors can be studied by in vivo nuclear magnetic resonance spectroscopy (NMRS). We have extended these observations by evaluating the pharmacokinetics of 5FU in the tumors of 11 patients with carcinoma of the breast, colon, endometrium, cervix, and kidney, using 19F-NMRS in a 1.5 Magnetom (Siemens Medical Systems, Cerrito, CA) magnetic resonance imaging unit (MRI). These NMRS measurements detected a long-lived tumor pool of 5FU in six of 11 tumors in our patients including carcinomas in the pelvis, breast, lung, and liver. The half-life (T1/2) of this tumor pool of "trapped" 5FU was 0.33 to 1.3 hours (20 to 78 minutes), much longer than the T1/2 of 5FU in blood (5 to 15 minutes). Neither the anabolites of 5FU (fluorinated nucleosides, nucleotides, 5FU-RNA, or 5FU-thymidylate synthase) nor the catabolites (eg, fluorobetaalanine [FBAL]) were detectable by 19F NMRS. Patient response to chemotherapy appeared to correlate with the extent of trapping of free 5FU in the human tumors: in the seven patients receiving 5FU, or 5FU or FUdR plus leucovorin, four of four patients whose tumors trapped 5FU responded to fluorinated pyrimidine chemotherapy, whereas three patients in whom there was a failure to detect tumor trapping were resistant to 5FU. We conclude that NMRS is clinically feasible, and enables investigators to study 5FU pharmacokinetics and metabolism in tumors in vivo. 19F-NMRS of 5FU allows for in vivo evaluation of 5FU metabolic modulation and might be able to guide therapeutic decisions.
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http://dx.doi.org/10.1200/JCO.1990.8.11.1868 | DOI Listing |
Arch Dermatol Res
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College of Pharmacy, Al-Mustaqbal University, 51001, Hillah, Babylon, Iraq.
Management of plane warts is difficult; techniques like cryotherapy and cauterization are linked with a significant number of recurrences, risk of scarring, pain, and costs. To evaluate the effectiveness of TCA 30% solution in comparison with tretinoin 0.05% cream and5-flurouracil (5-FU) 5% cream in treatment of plane wart.
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June 2025
Technology of Radiology and Medical Imaging Department, Faculty of Applied Health Science Technology, October 6 University, Egypt.
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January 2025
Department of Biology, Damghan Branch, Islamic Azad University, Damghan, Iran.
5-FU is a widely used chemotherapy drug for esophageal carcinomas, but therapy failure has been observed in 5-FU-resistant patients. Overcoming this resistance is a significant challenge in cancer treatment, requiring identifying and targeting important resistance mechanisms. PYGO2 expression is crucial in developing resistance to various chemotherapy drugs.
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December 2024
Institute of Biotechnology, Key Laboratory of Chemical Biology and Molecular Engineering of National Ministry of Education, Shanxi University, Taiyuan 030006, China.
Chemoresistance to 5-fluorouracil (5-FU) is a significant challenge in treating colorectal cancer (CRC). Novel combined regimens to thwart chemoresistance are therefore urgently needed. Herein, we demonstrated that the combination of Avenanthramide A (AVN A) and 5-FU has significant therapeutic advantages against CRC.
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March 2025
Department of Gastroenterology Surgery, Yichang Central People's Hospital, The First College of Clinical Medical Science, China Three Gorges University, Yichang, Hubei 443000, P.R. China.
Colorectal cancer (CRC) is one of the leading causes of cancer-related deaths worldwide. Glycolysis serves a crucial role in the development of CRC. The aim of the present study was to investigate the function of lectin galactoside-binding soluble 4 () in the regulation of glycolysis and its therapeutic potential in CRC.
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