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Badiga S, Siddiqui NR, Macaluso M, Johanning GL, Piyathilake CJ. Homocysteinemia is Associated with a Lower Degree of PBMC LINE-1 Methylation and a Higher Risk of CIN 2C in the U.S. Post-Folic Acid Fortification Era. Nutr Cancer 2016; 68:446-55. [DOI: 10.1080/01635581.2016.1152388] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Tomita LY, D'Almeida V, Villa LL, Franco EL, Cardoso MA. Polymorphisms in genes involved in folate metabolism modify the association of dietary and circulating folate and vitamin B-6 with cervical neoplasia. J Nutr 2013; 143:2007-14. [PMID: 24089416 DOI: 10.3945/jn.113.182212] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
High folate intake has been suggested as an important factor in cancer prevention; however, previous studies on the relation among folate intake, serum folate, and plasma homocysteine (hcy) are controversial. We conducted a hospital-based, case-control study in Brazil investigating associations between dietary and circulating vitamins B-6 and B-12 and folate, hcy, genotypes of folate-metabolizing enzyme methylenetetrahydrofolate reductase (MTHFR C677T, A1298C), 5-methyltetrahydrofolate-homocysteine methyltransferase (MTR A2756G), methionine synthase reductase (MTRR A66G), and reduced folate carrier (RFC1 G80A) and risk of cervical intraepithelial neoplasia (CIN) grades 1 (CIN1), 2 (CIN2), and 3 (CIN3). The study was composed by 453 controls, 140 CIN1, 126 CIN2, and 231 CIN3. We investigated the joint effects of genetic variants of folate-related genes using genetic risk scores (GRSs) by summing the number of risk alleles for CIN1 and CIN2+ (CIN2 and CIN3 cases). The OR (95% CI) for CIN1 and CIN2+ per each risk allele were 1.29 (1.01, 1.65) and 1.22 (1.01, 1.46), respectively. An association between folate intake and CIN2+ was observed only after stratification according to GRS: crude OR (95% CI) for lower folate intake and GRS ≥ 4 was 1.67 (0.92, 3.04) (P-trend < 0.001) compared with higher folate intake (above the median) and GRS ≤ 3. The CIN2+ risk of lower serum vitamin B-6 and GRS ≥ 4 was 2.14 (0.92, 5.02) (P-trend = 0.05) and lower serum folate (below the median) and GRS ≥ 4 was 0.49 (0.20, 1.17) (P-trend = 0.05) after adjustment for confounding variables and human papillomavirus infection. Our data suggest that polymorphisms in genes related to folate metabolism modify the association of dietary and circulating folate and vitamin B-6 with cervical neoplasia.
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Ragasudha PN, Thulaseedharan JV, Wesley R, Jayaprakash PG, Lalitha P, Pillai MR. A Case-Control Nutrigenomic Study on the Synergistic Activity of Folate and Vitamin B12 in Cervical Cancer Progression. Nutr Cancer 2012; 64:550-8. [DOI: 10.1080/01635581.2012.675618] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Xiao S, Tang YS, Khan RA, Zhang Y, Kusumanchi P, Stabler SP, Jayaram HN, Antony AC. Influence of physiologic folate deficiency on human papillomavirus type 16 (HPV16)-harboring human keratinocytes in vitro and in vivo. J Biol Chem 2012; 287:12559-77. [PMID: 22351779 DOI: 10.1074/jbc.m111.317040] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Although HPV16 transforms infected epithelial tissues to cancer in the presence of several co-factors, there is insufficient molecular evidence that poor nutrition has any such role. Because physiological folate deficiency led to the intracellular homocysteinylation of heterogeneous nuclear ribonucleoprotein E1 (hnRNP-E1) and activated a nutrition-sensitive (homocysteine-responsive) posttranscriptional RNA operon that included interaction with HPV16 L2 mRNA, we investigated the functional consequences of folate deficiency on HPV16 in immortalized HPV16-harboring human (BC-1-Ep/SL) keratinocytes and HPV16-organotypic rafts. Although homocysteinylated hnRNP-E1 interacted with HPV16 L2 mRNA cis-element, it also specifically bound another HPV16 57-nucleotide poly(U)-rich cis-element in the early polyadenylation element (upstream of L2L1 genes) with greater affinity. Together, these interactions led to a profound reduction of both L1 and L2 mRNA and proteins without effects on HPV16 E6 and E7 in vitro, and in cultured keratinocyte monolayers and HPV16-low folate-organotypic rafts developed in physiological low folate medium. In addition, HPV16-low folate-organotypic rafts contained fewer HPV16 viral particles, a similar HPV16 DNA viral load, and a much greater extent of integration of HPV16 DNA into genomic DNA when compared with HPV16-high folate-organotypic rafts. Subcutaneous implantation of 18-day old HPV16-low folate-organotypic rafts into folate-replete immunodeficient mice transformed this benign keratinocyte-derived raft tissue into an aggressive HPV16-induced cancer within 12 weeks. Collectively, these studies establish a likely molecular linkage between poor folate nutrition and HPV16 and predict that nutritional folate and/or vitamin-B(12) deficiency, which are both common worldwide, will alter the natural history of HPV16 infections and also warrant serious consideration as reversible co-factors in oncogenic transformation of HPV16-infected tissues to cancer.
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Affiliation(s)
- Suhong Xiao
- Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana 46202-5254, USA
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González CA, Travier N, Luján-Barroso L, Castellsagué X, Bosch FX, Roura E, Bueno-de-Mesquita HB, Palli D, Boeing H, Pala V, Sacerdote C, Tumino R, Panico S, Manjer J, Dillner J, Hallmans G, Kjellberg L, Sanchez MJ, Altzibar JM, Barricarte A, Navarro C, Rodriguez L, Allen N, Key TJ, Kaaks R, Rohrmann S, Overvad K, Olsen A, Tjønneland A, Munk C, Kjaer SK, Peeters PH, van Duijnhoven FJ, Clavel-Chapelon F, Boutron-Ruault MC, Trichopoulou A, Benetou V, Naska A, Lund E, Engeset D, Skeie G, Franceschi S, Slimani N, Rinaldi S, Riboli E. Dietary factors and in situ and invasive cervical cancer risk in the European prospective investigation into cancer and nutrition study. Int J Cancer 2010; 129:449-59. [DOI: 10.1002/ijc.25679] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2010] [Accepted: 06/10/2010] [Indexed: 11/09/2022]
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Kohaar I, Kumar J, Thakur N, Hussain S, Niyaz MK, Das BC, Sengupta S, Bharadwaj M. Homocysteine levels are associated with cervical cancer independent of methylene tetrahydrofolate reductase gene (MTHFR) polymorphisms in Indian population. Biomarkers 2010; 15:61-8. [DOI: 10.3109/13547500903295881] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Fletcher HM, Hanchard B. Poverty eradication and decreased human papilloma virus related cancer of the penis and vulva in Jamaica. J OBSTET GYNAECOL 2008; 28:333-5. [PMID: 18569481 DOI: 10.1080/01443610802044981] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Human papilloma virus causes genital cancers. Decreases in cervical cancer have been reported to be due to comprehensive screening programmes difficult to replicate in poorer countries. HPV cancer may be related to poverty. In Jamaica, we have seen decreases in cancer of the penis and vulva and there has also been a decrease in poverty. The decrease cannot be attributed to screening. We believe elimination of poverty has decreased HPV persistence and decreased cancer rates.
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Affiliation(s)
- H M Fletcher
- Department of Obstetrics and Gynaecology, University of the West Indies Mona, Kingston, Jamaica.
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Cho E, Zeisel SH, Jacques P, Selhub J, Dougherty L, Colditz GA, Willett WC. Dietary choline and betaine assessed by food-frequency questionnaire in relation to plasma total homocysteine concentration in the Framingham Offspring Study. Am J Clin Nutr 2006; 83:905-11. [PMID: 16600945 PMCID: PMC2430728 DOI: 10.1093/ajcn/83.4.905] [Citation(s) in RCA: 155] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Epidemiologic studies of choline and betaine intakes have been sparse because a food-composition database was not available until recently. The physiologic relevance of a variation in dietary choline and betaine in the general population and the validity of intake assessed by food-frequency questionnaire (FFQ) have not been evaluated. OBJECTIVE This study was conducted to examine the physiologic relevance and validity of choline and betaine intakes measured by an FFQ. DESIGN We examined the relations between choline and betaine intakes measured by FFQ and plasma total homocysteine (tHcy) concentrations in 1960 participants from the Framingham Offspring Study. RESULTS Higher intakes of dietary choline and betaine were related to lower tHcy concentrations independent of other determinants, including folate and other B vitamins. For the lowest and highest quintiles of dietary choline plus betaine, the multivariate geometric means for tHcy were 10.9 and 9.9 mumol/L (P for trend < 0.0001). The inverse association was manifested primarily in participants with low folate intakes (P for interaction < 0.0001). Among participants with folate intakes < or =250 microg/d, the geometric mean tHcy concentrations in the lowest and highest quintiles of choline plus betaine intakes were 12.4 and 10.2 micromol/L (P for trend < 0.0001). Except for choline from phosphatidylcholine, individual forms of choline were inversely associated with tHcy concentrations. CONCLUSIONS Our findings provide support for a physiologically important variation in choline and betaine intakes in the general population and for the validity of intake measured by FFQ.
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Affiliation(s)
- Eunyoung Cho
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Channing Laboratory, 181 Longwood Avenue, Boston, MA 02115, USA.
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Powers HJ. Interaction among folate, riboflavin, genotype, and cancer, with reference to colorectal and cervical cancer. J Nutr 2005; 135:2960S-2966S. [PMID: 16317155 DOI: 10.1093/jn/135.12.2960s] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Epidemiological studies have linked low folate intake with an increased risk of epithelial cancers, including colorectal cancer and cervical cancer. Riboflavin has received much less attention, but there is increasing interest in the well-established role that flavins play in folate metabolism and the possible synergy of a protective effect between these 2 vitamins. Folate plays a key role in DNA synthesis, repair, and methylation, and this forms the basis of mechanistic explanations for a putative role for folate in cancer prevention. The role of folate in these processes may be modulated by genotype for the common C677T thermolabile variant of methylene tetrahydrofolate reductase (MTHFR), homozygosity for which is associated with lower enzyme activity, lower plasma and red blood cell folate, and elevated plasma homocysteine. Riboflavin, as FAD, is a cofactor for MTHFR and there is evidently some interaction among riboflavin status, folate status, and genotype in determining plasma homocysteine, a functional marker of folate status. The MTHFR C677T polymorphism appears to interact with folate and riboflavin in modulating cancer risk in a manner that varies according to cancer site. Most evidence points to a protective effect of this polymorphism for risk of colorectal cancer, but the effect on cervical cancer risk is not clear. The effect of this polymorphism on cancer risk seems to be further modulated by other factors, including alcohol and, in the case of cervical cancer, infection with the human papilloma virus. An additional factor determining the effect of diet and genotype interactions on cancer risk may be the stage of cancer development.
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García-Closas R, Castellsagué X, Bosch X, González CA. The role of diet and nutrition in cervical carcinogenesis: A review of recent evidence. Int J Cancer 2005; 117:629-37. [PMID: 15912536 DOI: 10.1002/ijc.21193] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Our objective was to provide an update on recent epidemiologic evidence about the role of diet and nutrition on the risk of human papillomavirus (HPV) persistence and cervical neoplasia, taking HPV into account. We conducted a systematic review and qualitative classification of all observational studies controlling for HPV infection published between March 1995 and November 2003 and of all randomized clinical trials published between January 1991 and November 2003. Scientific evidence was classified as convincing, probable, possible or insufficient, as used in a previous study on diet and cancer. Thirty-three studies were eligible for this review (10 clinical trials, 8 observational prospective studies and 15 case-control studies). The few studies on HPV persistence showed a possible protective effect of fruits, vegetables, vitamins C and E, beta- and alpha-carotene, lycopene, luterin/zeaxanthin and cryptoxanthin. Evidence for a protective effect of cervical neoplasia was probable for folate, retinol and vitamin E and possible for vegetables, vitamins C and B12, alpha-carotene, beta-carotene, lycopene, lutein/zeaxanthin and cryptoxanthin. Evidence for an increased risk of cervical neoplasia associated with high blood homocysteine was probable. Results did not differ between studies looking at preneoplastic and invasive lesions or between retrospective and prospective studies. The available evidence for an association between diet and nutritional status and cervical carcinogenesis taking HPV infection into account is not yet convincing. Large cohort studies are needed to adequately assess the role of foods and nutrients in cervical HPV carcinogenesis.
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Affiliation(s)
- Reina García-Closas
- Cancer Epidemiology and Registration Unit, Institut Català d'Oncologia (ICO), L'Hospitalet de Llobregat, Barcelona, Spain
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Sedjo RL, Fowler BM, Schneider A, Henning SM, Hatch K, Giuliano AR. Folate, vitamin B12, and homocysteine status. findings of no relation between human papillomavirus persistence and cervical dysplasia. Nutrition 2003; 19:497-502. [PMID: 12781848 DOI: 10.1016/s0899-9007(02)01096-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVES Human papillomavirus (HPV) infections are the cause of most, if not all, cervical cancers. Women consistently positive for oncogenic type HPV infections have a greater risk of developing cervical dysplasia compared with women transiently infected. HPV infection alone appears to be insufficient to produce disease, suggesting that other cofactors may be needed. Folate, vitamin B12, and homocysteine, through their role in DNA methylation, may be involved in cervical neoplasia. METHODS This study examined the associations between HPV persistence and circulating folate, vitamin B12, and homocysteine levels among 91 low-income Hispanic women. Further, the relation of these nutrients to cervical pathology was evaluated. HPV status was determined at two visits approximately 3 mo apart. RESULTS Adjusted mean circulating concentrations of folate, vitamin B12, and homocysteine were not statistically different between women with two positive HPV tests, one positive test, or two negative HPV tests. No association was observed between tertiles of folate, vitamin B12, or homocysteine and HPV persistence risk. Further, adjusted mean levels of these nutrients were not statistically different between cytologic grades. CONCLUSIONS Results from this small study did not support a role for folate, vitamin B12, or homocysteine in HPV persistence or cervical dysplasia.
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Affiliation(s)
- Rebecca L Sedjo
- Arizona Cancer Center, 1515 N. Campbell Avenue, Room 4977 C, Phoenix, AZ 85724-5024, USA
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de la Calle M, Usandizaga R, Sancha M, Magdaleno F, Herranz A, Cabrillo E. Homocysteine, folic acid and B-group vitamins in obstetrics and gynaecology. Eur J Obstet Gynecol Reprod Biol 2003; 107:125-34. [PMID: 12648856 DOI: 10.1016/s0301-2115(02)00305-6] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The amino acid homocysteine is of considerable medical importance because it is involved in the etiopathogeny of cardiovascular diseases. Hyperhomocysteinemia is a factor in the vascular damage that predisposes thrombogenesis and arteriosclerosis. It has also been related to a range of obstetric and gynecologic complications. Numerous studies have demonstrated the association between increased levels of homocysteine and neural tube defects (NTD) and other congenital defects, spontaneous miscarriages, intrauterine growth retardation (IGR), preeclampsia and intrauterine fetal death. Folic acid and other B-group vitamins (B6 and B12) take part in the metabolism of homocysteine and the preventive administration of these vitamins may reduce some of the complications.
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Affiliation(s)
- M de la Calle
- Department of Obstetrics and Gynaecology, Hospital La Paz, Paseo de la Castellana n 261, 28046 Madrid, Spain
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Cox JT. Management of precursor lesions of cervical carcinoma: history, host defense, and a survey of modalities. Obstet Gynecol Clin North Am 2002; 29:751-85. [PMID: 12509095 DOI: 10.1016/s0889-8545(02)00048-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Before the initiation of screening and treatment for cervical cancer precursors, approximately 3% to 4% of women were destined to eventually develop cervical cancer. During the last 50 years the rate of cervical cancer incidence and mortality has decreased by more than 75% primarily because of the widespread availability of cervical cytologic screening and of treatment for documented cervical precancer. Successful screening of the entire population and appropriate treatment of lesions could theoretically reduce this risk to one tenth of the risk of an unscreened population [7,28]. The relatively recent understanding of the etiology of cervical cancer precursor lesions and of the immune response to them has given new direction to management options that incorporate healthy habits and dietary measures as part of traditional ablative or excisional treatment options. As we look to the future we can expect that new markers that more specifically identify individuals at-risk for cervical precancer and cancer will be developed and take precedence in cervical screening. At the same time, treating the cause of these lesions, rather than the result, should provide less traumatic and more successful therapies. To this end, harnessing the immune system through immune response modifiers and HPV vaccines seems to be on the horizon, as do new chemopreventative approaches. Of all human cancers, only cervical cancer, once the second most common cancer among women, stands on the threshold of being virtually eliminated.
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Affiliation(s)
- J Thomas Cox
- Gynecology Clinic, Health Services. University of California, Santa Barbara, CA 93106, USA.
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Ziegler RG, Weinstein SJ, Fears TR. Nutritional and genetic inefficiencies in one-carbon metabolism and cervical cancer risk. J Nutr 2002; 132:2345S-2349S. [PMID: 12163690 DOI: 10.1093/jn/132.8.2345s] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Folate deficiency has long been postulated to play a role in the etiology of cervical cancer, the third most frequent cancer among women worldwide. In a large, multiethnic community-based case-control study of invasive cervical cancer in five U.S. areas, we assessed accepted and postulated risk factors with an in-home interview and successfully obtained blood samples, at least 6 mo after completion of cancer treatment, from 51 and 68%, respectively, of interviewed cases and controls. Cases with advanced disease (6%) and/or receiving chemotherapy (4%) were excluded, leaving 183 cases and 540 controls. Serum and red blood cell folate were measured with both microbiologic and radiobinding assays. For all four folate measures, risk was moderately, but nonsignificantly, elevated for women in the lowest quartile, compared to the highest [fully adjusted relative risks (RR), including serologic human papillomavirus (HPV)-16 status = 1.2-1.6]. However, for women in the upper three homocysteine quartiles (>6.31 micro mol/L), risk of invasive cervical cancer was substantially and significantly elevated (fully adjusted RR, including serologic HPV-16 status = 2.4-3.2; P for trend = 0.01). This strong relationship suggests that circulating homocysteine may be 1) an especially accurate indicator of inadequate folate, 2) an integratory measure of insufficient folate in tissues or 3) a biomarker of disruption of one-carbon metabolism. The contribution of common polymorphisms in one-carbon pathway genes, as well as inadequate vitamin B-6, vitamin B-12 and/or riboflavin, to elevated homocysteine, inefficient one-carbon metabolism and increased cervical cancer risk merits further exploration.
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Affiliation(s)
- Regina G Ziegler
- Epidemiology and Biostatistics Program, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD 20892, USA.
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Weinstein SJ, Gridley G, Harty LC, Diehl SR, Brown LM, Winn DM, Bravo-Otero E, Hayes RB. Folate intake, serum homocysteine and methylenetetrahydrofolate reductase (MTHFR) C677T genotype are not associated with oral cancer risk in Puerto Rico. J Nutr 2002; 132:762-7. [PMID: 11925474 DOI: 10.1093/jn/132.4.762] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We examined the relationships between folate and methionine intake, serum homocysteine levels (as a biomarker for folate metabolism), and methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism genotype and risk of oral cancer in a population-based, case-control study in Puerto Rico. Structured questionnaires were used to collect information on demographic factors, usual adult diet, and tobacco and alcohol use. Oral epithelial cells and blood samples were collected from a subset of subjects. Analyses were conducted by logistic regression, adjusting for age, sex, lifetime smoking and lifetime alcohol intake, with the following numbers of cases/controls, respectively: dietary data (341/521); MTHFR genotype (148/149); and homocysteine (60/90). Although increased folate intake was associated with decreased oral cancer risk [adjusted odds ratio (OR) in highest vs. lowest quartile = 0.6, 95% confidence interval (CI): 0.4, 1.0, P(trend) = 0.05)], this finding was due almost entirely to folate intake from fruit (adjusted OR = 0.4, 95% CI: 0.2, 0.6; P(trend) = 0.0001), whereas other dietary folate sources showed no clear association. Methionine intake and serum homocysteine levels were not associated with oral cancer risk. Subjects with the MTHFR C677T homozygous variant (TT) genotype had a nonsignificantly lower risk, and risk patterns tended to differ by level of folate, methionine, alcohol intake and smoking, although the power to detect significant associations in subgroups of these variables was low. Risks for oral cancer are not folate specific; preventive recommendations for this disease should emphasize the importance of a healthy diet, including substantial intake of fruits.
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Affiliation(s)
- Stephanie J Weinstein
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD 20892, USA.
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