Folate and colorectal cancer prevention.
Br J Cancer
; 100(2): 233-9, 2009 Jan 27.
Article
em En
| MEDLINE
| ID: mdl-19088716
ABSTRACT
Anti-folate chemotherapy agents such as methotrexate and fluorouracil reduce proliferation of neoplastic cells by inhibiting DNA synthesis. Paradoxically epidemiological data suggests an inverse relationship between dietary folate intake and incidence of colorectal cancer (CRC). On the basis of this and other putative health benefits around 35% of the North American population take folic acid supplements, in addition to natural food folates and fortified flour and cereal grains. Recently, randomised controlled trials investigating folic acid as a secondary preventative agent in colorectal neoplasia have shed further light on the relationship between folate and colorectal carcinogenesis, corroborating data from animal models indicating opposing effects dependent on the timing of exposure in relation to the development of neoplastic foci. A 'dual-modulator' role for folate in colorectal carcinogenesis has been proposed in which moderate dietary increases initiated before the establishment of neoplastic foci have a protective influence, whereas excessive intake or increased intake once early lesions are established increases tumorigenesis. Functional polymorphic variants in genes encoding key enzymes in the folate metabolic pathway add a further layer of complexity to the relationship between folate and CRC risk. Here, we review the evidence concerning the efficacy and safety of folate as a potential CRC chemopreventive agent.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Complexo Vitamínico B
/
Neoplasias Colorretais
/
Ácido Fólico
Tipo de estudo:
Clinical_trials
Limite:
Humans
Idioma:
En
Revista:
Br J Cancer
Ano de publicação:
2009
Tipo de documento:
Article
País de afiliação:
Reino Unido