Nutritional folate status influences the efficacy and toxicity of chemotherapy in rats.
The effect of folate status on the efficacy and toxicity of chemotherapy was investigated in weanling Fischer 344 rats maintained on diets of varying folate content or supplemented with daily injections of folic acid, 50 mg/kg, for 6 to 7 weeks. MADB106 rat mammary tumor growth rate was the same in folate replete and supplemented rats, but retarded in the low folate groups. The tumor growth inhibitions in low folate, replete and high folate rats treated with cyclophosphamide were: 53%, 98%, and 97% (P = .048); with 5-fluorouracil (5-FU): 46%, 49%, and 66%; and with doxorubicin: 25%, 55%, and 61%. Significant differences in survival were observed for cyclophosphamide (P = .0084) and 5-FU (P = .025) related to dietary folate content. Thus, folate deficiency impedes tumor growth rate, but supplementation does not accelerate it in folate replete animals. Correction of folate deficiency approximately doubles the efficacy of cyclophosphamide in rats with much less host toxicity. Folate repletion improves survival in 5-FU-treated animals. These studies indicate that nutritional folate status has an important influence on the efficacy and toxicity of some commonly used cancer chemotherapeutic drugs.
Branda
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RF
Departments of Medicine and Pharmacology and the Vermont Cancer Center, University of Vermont, Burlington, VT 05401, USA.
Nigels
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Lafayette
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AR
Hacker
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D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000627:therapeutic use / Q000633:toxicity*; D000964:Antimetabolites, Antineoplastic / Q000627:therapeutic use / Q000633:toxicity*; D018906:Antineoplastic Agents, Alkylating / Q000627:therapeutic use / Q000633:toxicity*; D003520:Cyclophosphamide / Q000627:therapeutic use / Q000633:toxicity*; D018450:Disease Progression; D004317:Doxorubicin / Q000494:pharmacology / Q000627:therapeutic use*; D005260:Female; D005472:Fluorouracil / Q000627:therapeutic use / Q000633:toxicity*; D005492:Folic Acid / Q000008:administration & dosage / Q000502:physiology* / Q000627:therapeutic use; D005494:Folic Acid Deficiency / Q000150:complications* / Q000188:drug therapy; D008325:Mammary Neoplasms, Experimental / Q000150:complications / Q000188:drug therapy* / Q000473:pathology; D009368:Neoplasm Transplantation; D009752:Nutritional Status; D051381:Rats; D011916:Rats, Inbred F344; D012074:Remission Induction; D014407:Tumor Cells, Cultured
D000903:Antibiotics, Antineoplastic; D000964:Antimetabolites, Antineoplastic; D018906:Antineoplastic Agents, Alkylating; D004317:Doxorubicin; D003520:Cyclophosphamide; D005492:Folic Acid; D005472:Fluorouracil