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Background: ω-3 polyunsaturated fatty acids (PUFA) could play a protective role on the risk of breast cancer; however, little is known about this relation among Mexican women. We evaluated the association between ω-3 and ω-6 PUFA intake and breast cancer risk by obesity status in Mexican women., Methods: A population-based case-control study was conducted in Mexico, including 1,000 incident breast cancer cases and 1,074 controls matched to cases by age, health care system, and region. Women provided information on health and diet by in-person interview. Body mass index (BMI) measures were used to define overall obesity. Obesity status was categorized as normal weight (18.5 < BMI < 25), overweight (25 ≤ BMI < 30), and obese (BMI ≥ 30). A conditional logistic regression model was used to assess the association between PUFA and breast cancer risk., Results: Overall, there was no significant association between ω-3 PUFA intake and breast cancer risk (P = 0.31). An increased risk of breast cancer was associated with increasing ω-6 PUFA intake in premenopausal women [OR = 1.92, 95% confidence interval (CI) = 1.13-3.26; P = 0.04]. A decreased risk of breast cancer was significantly associated with increasing ω-3 PUFA intake in obese women (OR = 0.58, 95% CI = 0.39-0.87; P = 0.008) but not in normal weight nor in overweight women (P(heterogeneity) = 0.017)., Conclusions: Obesity status may affect the association between ω-3 PUFA intake and breast cancer risk. The underlying mechanisms may be related to decreased inflammation and improved adipokin and estrogen levels induced by ω-3 PUFA in adipose tissue in obese women., Impact: Increased intake of ω-3 PUFA should be recommended among Mexican women in particular in obese women., (©2011 AACR.)

Elaidic acid is the main unnatural trans fatty acid isomer occurring during partial hydrogenation of vegetable oils used as ingredients for the formulation of processed foods. The main objective is to assess associations between processed food intakes and plasma phospholipid elaidic acid concentrations within the European Prospective Investigation into Cancer and Nutrition study. A cross-sectional study was used to determine fatty acid profiles in 3,003 subjects from 16 centers. Single 24-h dietary recalls (24-HDR) were collected using a standardized computerized interview program. Food intakes were computed according to their degree of processing (moderately/nonprocessed foods, processed staple foods, highly processed foods). Adjusted ecological and individual correlations were calculated between processed food intakes and plasma elaidic acid levels. At the population level, mean intakes of highly processed foods were strongly correlated with mean levels of plasma elaidic acid in men (P = 0.0016) and in women (P = 0.0012). At the individual level, these associations remained but at a much lower level in men (r = 0.08, P = 0.006) and in women (r = 0.09, P = 0.0001). The use of an averaged 24-HDR measure of highly processed food intakes is adequate for predicting mean levels of plasma elaidic acid among European populations.

Background: Epidemiologic data suggest that diet is a risk factor in the etiology of gastric cancer. However, the role of dietary fatty acids, a modifiable risk factor, remains relatively unexplored., Objective: The objective of this study was to determine the association of plasma phospholipid fatty acid concentrations, as biomarkers of exogenous and endogenously derived fatty acids, with the risk of gastric adenocarcinoma in a case-control study nested within the European Prospective Investigation into Cancer and Nutrition-Europe Gastric Cancer (EPIC-EURGAST)., Design: Fatty acids were measured by gas chromatography in prediagnostic plasma phospholipids from 238 cases matched to 626 controls by age, sex, study center, and date of blood donation. Conditional logistic regression models adjusted for Helicobacter pylori infection status, BMI, smoking, physical activity, education, and energy intake were used to estimate relative cancer risks., Results: Positive risk associations for gastric cancer were observed in the highest compared with the lowest quartiles of plasma oleic acid (OR: 1.72; 95% CI: 1.01, 2.94), di-homo-γ-linolenic acid (OR: 1.92; 95% CI: 1.10, 3.35), α-linolenic acid (OR: 3.20; 95% CI: 1.70, 6.06), and the ratio of MUFAs to saturated fatty acids, as an indicator of stearoyl-CoA desaturase-1 enzyme activity (OR: 1.40; 95% CI: 0.81, 2.43). An inverse risk association was observed with the ratio of linoleic to α-linolenic acid (OR: 0.37; 95% CI: 0.20, 0.66)., Conclusion: These data suggest that a specific prediagnostic plasma phospholipid fatty acid profile, characterized mainly by high concentrations of oleic acid, α-linolenic acid, and di-homo-γ-linolenic acid, which presumably reflect both a complex dietary pattern and altered fatty acid metabolism, may be related to increased gastric cancer risk.

Purpose of Review: This review summarizes epidemiological data linking the fatty acid desaturation index measured in blood lipids, as a biomarker of hepatic stearoyl-CoA desaturase activity, the key enzyme involved in the synthesis of monounsaturated fatty acids from saturated fatty acids, to breast cancer risk. The biological plausibility of this association is discussed., Recent Findings: Epidemiological cohort studies reported an association between a high saturated to monounsaturated fatty acid ratio measured in blood lipids, indicating low stearoyl-CoA desaturase-1 activity, and decreased breast cancer risk. The suppression of stearoyl-CoA desaturase expression reduces cancer cell proliferation and in-vitro invasiveness, and dramatically impairs tumor formation and growth. These effects could not be overcome by supplying exogenous monounsaturated fatty acids., Summary: Epidemiological findings, in accordance with experimental data, suggested that decreased hepatic stearoyl-CoA desaturase expression/activity may be related to decreased risk of breast cancer.

Objective: We investigated the association between the proportion of long-chain n-3 polyunsaturated fatty acids (PUFA) in plasma phospholipids from blood samples drawn at enrollment and subsequent change in body weight. Sex, age, and BMI were considered as potential effect modifiers., Method: A total of 1,998 women and men participating in the European Prospective Investigation into Cancer and Nutrition (EPIC) were followed for a median of 4.9 years. The associations between the proportion of plasma phospholipid long-chain n-3 PUFA and change in weight were investigated using mixed-effect linear regression., Results: The proportion of long-chain n-3 PUFA was not associated with change in weight. Among all participants, the 1-year weight change was -0.7 g per 1% point higher long-chain n-3 PUFA level (95% confidence interval: -20.7 to 19.3). The results when stratified by sex, age, or BMI groups were not systematically different., Conclusion: The results of this study suggest that the proportion of long-chain n-3 PUFA in plasma phospholipids is not associated with subsequent change in body weight within the range of exposure in the general population., (Copyright © 2011 S. Karger AG, Basel.)

Evidence of a protective effect of fruit and vegetable intake on breast cancer risk is inconsistent. Epidemiologic cohort studies based on blood carotenoid intakes as biomarkers of consumption of fruits and vegetable in individuals are still scare and findings are discrepant. The study population included women in the E3N Study, the large French component of the European Prospective Investigation into Cancer and Nutrition (EPIC). During an average of 7 years follow-up, 366 cases of incident invasive breast cancer (84 premenopausal women and 282 postmenopausal women) among 19,934 women who completed a dietary questionnaire and had available blood samples at baseline (1995-1998) were included in the study. Controls were randomly matched on age, menopausal status at blood collection, fasting status at blood collection, date and collection center. Serum carotenoids, tocopherols and retinol concentrations were assessed by high pressure liquid chromatography. Odds ratios for breast cancer risk adjusted for established breast cancer risk factors were calculated by quintile of serum micronutrient concentrations. No significant associations between breast cancer risk and serum carotenoids (highest versus lowest quintile, odds ratio (OR) = 0.74, 95% confidence interval (CI) = 0.47-1.16, p for trend 0.38), tocopherols (OR = 0.68, 95% CI = 0.41-1.10, p for trend 0.26) and retinol (OR = 0.85, 95% CI = 0.53-1.35, p for trend 0.34) were found. Our findings did not support the hypothesis that lipophilic antioxidant micronutrients found in fruits and vegetables protect against breast cancer, at least in postmenopausal women.

Objectives: This paper describes the dietary intake of total fat, saturated (SFA), monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA) and cholesterol of participants in the European Prospective Investigation into Cancer and Nutrition (EPIC) in 27 centres across 10 countries., Methods: Between 1995 and 2000, a stratified random sample of 36 034 participants (age range 35-74 years) completed a standardized 24-h dietary recall, assessed by means of the computer software EPIC-SOFT. Lipid intake data were calculated using a standardized nutrient database., Results: On average, the contribution of fat to total energy intake was >or=34% of energy intake (%en) in women and >or=36%en in men for most EPIC centres, except for the British, Dutch and most Italian cohorts. Total fat (>40%en) and MUFA intakes (21%en, mainly from olive oil) were highest in Greece. Except for the Greek, Spanish and Italian centres, the average MUFA intake ranged between 10 and 13%en, with a high proportion derived from animal sources. SFA intake in women and men was lowest in the Greek, Spanish, Italian and UK cohorts with an average of

Objectives: To describe the contribution of highly processed foods to total diet, nutrient intakes and patterns among 27 redefined centres in the 10 countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC)., Methods: Single 24-hour dietary recalls were collected from 36,034 individuals (aged 35-74 years) using a standardized computerized interview programme (EPIC-SOFT). Centre-specific mean food intakes (g/day) were computed according to their degree of food processing (that is, highly, moderately and non-processed foods) using a specifically designed classification system. The contribution (%) of highly processed foods to the centre mean intakes of diet and 26 nutrients (including energy) was estimated using a standardized nutrient database (ENDB). The effect of different possible confounders was also investigated., Results: Highly processed foods were an important source of the nutrients considered, contributing between 61% (Spain) and 78-79% (the Netherlands and Germany) of mean energy intakes. Only two nutrients, beta-carotene (34-46%) and vitamin C (28-36%), had a contribution from highly processed foods below 50% in Nordic countries, in Germany, the Netherlands and the United Kingdom, whereas for the other nutrients, the contribution varied from 50 to 91% (excluding alcohol). In southern countries (Greece, Spain, Italy and France), the overall contribution of highly processed foods to nutrient intakes was lower and consisted largely of staple or basic foods (for example, bread, pasta/rice, milk, vegetable oils), whereas highly processed foods such as crisp bread, breakfast cereals, margarine and other commercial foods contributed more in Nordic and central European centres., Conclusions: Highly industrially processed foods dominate diets and nutrient patterns in Nordic and central European countries. The greater variations observed within southern countries may reflect both a larger contribution of non/moderately processed staple foods along with a move from traditional to more industrialized dietary patterns.

Experimental studies suggest detrimental effects of omega-6 polyunsaturated fatty acids (PUFA), and beneficial effects of omega-3 PUFAs on mammary carcinogenesis, possibly in interaction with antioxidants. However, PUFA food sources are diverse in human diets and few epidemiologic studies have examined whether associations between dietary PUFAs and breast cancer risk vary according to food sources or antioxidant intakes. The relationship between individual PUFA intakes estimated from diet history questionnaires and breast cancer risk was examined among 56,007 French women. During 8 years of follow-up, 1,650 women developed invasive breast cancer. Breast cancer risk was not related to any dietary PUFA overall; however, opposite associations were seen according to food sources, suggesting other potential effects than PUFA per se. Breast cancer risk was inversely associated with alpha-linolenic acid (ALA) intake from fruit and vegetables [highest vs. lowest quintile, hazard ratio (HR) 0.74; 95% confidence interval (CI) 0.63, 0.88; p trend < 0.0001], and from vegetable oils (HR 0.83; 95% CI 0.71, 0.97; p trend 0.017). Conversely, breast cancer risk was positively related to ALA intake from nut mixes (p trend 0.004) and processed foods (p trend 0.068), as was total ALA intake among women in the highest quintile of dietary vitamin E (p trend 0.036). A significant interaction was also found between omega-6 and long-chain omega-3 PUFAs, with breast cancer risk inversely related to long-chain omega-3 PUFAs in women belonging to the highest quintile of omega-6 PUFAs (p interaction 0.042). These results emphasize the need to consider food sources, as well as interactions between fatty acids and with antioxidants, when evaluating associations between PUFA intakes and breast cancer risk.

Background: Plasma phospholipid fatty acids have been correlated with food intakes in populations with homogeneous dietary patterns. However, few data are available on populations with heterogeneous dietary patterns., Objective: The objective was to investigate whether plasma phospholipid fatty acids are suitable biomarkers of dietary intakes across populations involved in a large European multicenter study., Design: A cross-sectional study design nested to the European Prospective Investigation into Cancer and Nutrition (EPIC) was conducted to determine plasma fatty acid profiles in >3,000 subjects from 16 centers, who had also completed 24-h dietary recalls and dietary questionnaires. Plasma fatty acids were assessed by capillary gas chromatography. Ecological and individual correlations were calculated between fatty acids and select food groups., Results: The most important determinant of plasma fatty acids was region, which suggests that the variations across regions are largely due to different food intakes. Strong ecological correlations were observed between fish intake and long-chain n-3 polyunsaturated fatty acids (r = 0.78, P < 0.01), olive oil and oleic acid (r = 0.73, P < 0.01), and margarine and elaidic acid (r = 0.76, P < 0.01). Individual correlations varied across the regions, particularly between olive oil and oleic acid and between alcohol and the saturation index, as an indicator of stearoyl CoA desaturase activity., Conclusions: These findings indicate that specific plasma phospholipid fatty acids are suitable biomarkers of some food intakes in the EPIC Study. Moreover, these findings suggest complex interactions between alcohol intake and fatty acid metabolism, which warrants further attention in epidemiologic studies relating dietary fatty acids to alcohol-related cancers and other chronic diseases.

The fatty acid composition of serum phospholipids has been shown to reflect dietary intakes in the previous weeks or months. However, how serum phospholipids relate to fatty acid intakes over a few years has hardly been examined. We designed a cross-sectional study within the E3N cohort, the French component of the European Prospective Investigation into Cancer and Nutrition in which female participants completed a 208-item diet history questionnaire in 1993-1995 and provided blood samples in 1995-1998. The study included 1,114 women who were free of cancer at the time of blood collection. Serum phospholipid fatty acid composition was assessed by capillary gas chromatography. Partial Spearman correlations adjusted for age and body mass index showed weak to moderate, although statistically significant, positive associations between dietary and serum oleic, linoleic, arachidonic, eicosapentaenoic, and docosahexaenoic acids. Moreover, serum oleic acid was directly associated with olive oil, linoleic acid with sunflower oil, pentadecanoic acid with dairy products, long-chain n-3 fatty acids with fatty fish, and trans-monounsaturated fatty acids with manufactured foods. In conclusion, serum phospholipid pentadecanoic acid, oleic, trans-monounsaturated, and polyunsaturated fatty acids are suitable biomarkers for usual dietary intakes, although the association may weaken as the time lag between dietary assessment and blood collection increases.

The authors assessed the association between serum phospholipid fatty acids as biomarkers of fatty acid intake and breast cancer risk among women in the E3N Study (1989-2002), the French component of the European Prospective Investigation into Cancer and Nutrition. During an average of 7 years of follow-up, 363 cases of incident invasive breast cancer were documented among 19,934 women who, at baseline (1995-1998), had completed a diet history questionnaire and provided serum samples. Controls were randomly matched to cases by age, menopausal status at blood collection, fasting status at blood collection, date, and collection center. Serum phospholipid fatty acid composition was assessed by gas chromatography. Adjusted odds ratios for risk of breast cancer with increasing levels of fatty acids were calculated using conditional logistic regression. An increased risk of breast cancer was associated with increasing levels of the trans-monounsaturated fatty acids palmitoleic acid and elaidic acid (highest quintile vs. lowest: odds ratio = 1.75, 95% confidence interval: 1.08, 2.83; p-trend = 0.018). cis-Monounsaturated fatty acids were unrelated to breast cancer risk. A high serum level of trans-monounsaturated fatty acids, presumably reflecting a high intake of industrially processed foods, is probably one factor contributing to increased risk of invasive breast cancer in women.

To clarify the role of metabolic factors in endometrial carcinogenesis, we conducted a case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC), and examined the relation between prediagnostic plasma lipids, lipoproteins, and glucose, the metabolic syndrome (MetS; a cluster of metabolic factors) and endometrial cancer risk. Among pre- and postmenopausal women, 284 women developed endometrial cancer during follow-up. Using risk set sampling, 546 matched control subjects were selected. From conditional logistic regression models, high-density lipoprotein cholesterol (HDL-C) levels were inversely associated with risk body mass index (BMI)-adjusted relative risk (RR) for top versus bottom quartile 0.61 (95% confidence intervals (CI) 0.38-0.97), P(trend) = 0.02). Glucose levels were positively associated with risk (BMI-adjusted RR top versus bottom quartile 1.69 (95% CI 0.99-2.90), P(trend) = 0.03), which appeared stronger among postmenopausal women (BMI-adjusted RR top versus bottom tertile 2.61 (95% CI 1.46-4.66), P(trend) = 0.0006, P(heterogeneity) = 0.13) and never-users of exogenous hormones (P(heterogeneity) = 0.005 for oral contraceptive (OC) use and 0.05 for hormone replacement therapy-use). The associations of HDL-C and glucose with risk were no longer statistically significant after further adjustment for obesity-related hormones. Plasma total cholesterol, Low-density lipoprotein cholesterol (LDL-C), and triglycerides were not significantly related to overall risk. The presence of MetS was associated with risk (RR 2.12 (95% CI 1.51-2.97)), which increased with the number of MetS factors (P(trend) = 0.02). An increasing number of MetS factors other than waist circumference, however, was marginally significantly associated with risk only in women with waist circumference above the median (P(interaction) = 0.01). None of the associations differed significantly by fasting status. These findings suggest that metabolic abnormalities and obesity may act synergistically to increase endometrial cancer risk.

A key fatty acid synthesis enzyme, acetyl-CoA carboxylase alpha (ACC-alpha), has been shown to be highly expressed in human breast cancer and other tumor types and also to specifically interact with the protein coded by one of two major breast cancer susceptibility genes BRCA1. We used a comprehensive haplotype analysis to examine the contribution of the ACC-alpha common genetic variation (allele frequency >5%) to breast cancer in a case-control study (1,588 cases/2,600 controls) nested within the European Prospective Investigation into Cancer and Nutrition. We identified 21 haplotype-tagging polymorphisms efficiently capturing common variation within 325 kb of ACC-alpha and surrounding sequences using genotype data from the HapMap project and our resequencing data. We found an effect on overall risk of breast cancer in homozygous carriers of one common haplotype [odds ratio (OR), 1.74; 95% confidence interval (95% CI), 1.03-2.94]. When the data were subdivided by menopausal status, we found statistical evidence of heterogeneity for two other common haplotypes (P value for heterogeneity = 0.016 and 0.045). In premenopausal women, the carriers of these haplotypes, compared with noncarriers, had an altered risk of breast cancer (OR, 0.70; 95% CI, 0.53-0.92 and OR, 1.35; 95% CI, 1.04-1.76). These findings were not significant after adjustment for multiple testing and therefore should be considered as preliminary and evaluated in larger independent studies. However, they suggest a possible role of the ACC-alpha common sequence variants in susceptibility to breast cancer and encourage studies of other genes involved in fatty acid synthesis.

There is current interest in fish consumption and marine omega-3 (n-3) fatty acids and breast cancer risk. Some in vitro and animal studies have suggested an inhibitory effect of marine n-3 fatty acids on breast cancer growth, but the results from epidemiological studies that have examined the association between fish consumption and breast cancer risk in humans are inconsistent. We examined fish consumption and breast cancer risk in 310,671 women aged between 25 and 70 yr at recruitment into the European Prospective Investigation Into Cancer and Nutrition (EPIC). The participants completed a dietary questionnaire between 1992-98 and were followed up for incidence of breast cancer for a median of 6.4 yr. Hazard ratio for breast cancer by intake of total and lean and fatty fish were estimated, stratified by study centre and adjusted for established breast cancer risk factors. During follow-up, 4,776 invasive incident breast cancers were reported. No significant associations between intake of total fish and breast cancer risk were observed, hazard ratio (HR) 1.01 (95% confidence interval [CI] 0.99-1.02; p = 0.28 per 10 g fish/day). When examining lean and fatty fish separately, we found a positive significant association only in the highest quintile for fatty fish (HR 1.13, 95% CI 1.01-1.26), but test for trend was not significant (p = 0.10). No associations with breast cancer risk were observed when the study participants were subdivided by menopausal status. Although the period of follow-up is relatively short, the results provide no evidence for an association between fish intake and breast cancer risk.

To investigate whether dietary alpha-linolenic acid (ALA) content alters the effect of beta-carotene on mammary carcinogenesis, we conducted a chemically induced mammary tumorigenesis experiment in rats randomly assigned to four nutritional groups (15 rats per group) varying in beta-carotene supplementation and ALA content. Two oil formula-enriched diets (15 %) were used: one with 6 g ALA/kg diet in an essential fatty acids (EFA) ratio of linoleic acid:ALA of 5:1 w/w (EFA 5 diet), the other with 24 g ALA/kg diet in an EFA ratio of 1:1 w/w (EFA 1 diet), both designed with a similar linoleic acid content. beta-Carotene was either added (10 mg/kg diet per d) or not added to these diets. beta-Carotene supplementation led to decreased tumour incidence and tumour growth when added to the EFA 5 diet, whereas it had no effect when added to the EFA 1 diet. The decreased tumour growth did not result from an involvement of lipoperoxidation (tumour malondialdehyde content being similar between the groups) or from an inhibition of tumour cell proliferation (as there was an unchanged S phase fraction in the tumours). We concluded that an adequate content of ALA in the diet is required to allow a protective effect of beta-carotene in mammary carcinogenesis. Whether such an interaction between ALA and beta-carotene influences the risk of breast cancer in women needs to be investigated.

Activation of de novo fatty acid synthesis is a characteristic feature of cancer cells. We have recently described an interaction between acetyl-CoA carboxylase alpha (ACCalpha), a key enzyme in fatty acid synthesis, and BRCA1, which indicates a possible connection between lipid synthesis and genetic factors involved in susceptibility to breast and ovarian cancers. For this reason, we explored the role of ACCalpha in breast cancer cell survival using an RNA interference (RNAi) approach. We show that specific silencing of either the ACCalpha or the fatty acid synthase (FAS) genes in cancer cells results in a major decrease in palmitic acid synthesis. Depletion of the cellular pool of palmitic acid is associated with induction of apoptosis concomitant with the formation of reactive oxygen species (ROS) and mitochondrial impairment. Expression of a small interfering RNA (siRNA)-resistant form of ACCalpha mRNA prevented the effect of ACCalpha-RNAi but failed to prevent the effect of FAS gene silencing. Furthermore, supplementation of the culture medium with palmitate or with the antioxidant vitamin E resulted in the complete rescue of cells from both ACCalpha and FAS siRNA-induced apoptosis. Finally, human mammary epithelial cells are resistant to RNAi against either ACCalpha or FAS. These data confirm the importance of lipogenesis in cancer cell survival and indicate that this pathway represents a key target for antineoplastic therapy that, however, might require specific dietary recommendation for full efficacy.

Insulin-like growth factor I (IGF-I) stimulates cell proliferation and can enhance the development of tumours in different organs. Epidemiological studies have shown that an elevated level of circulating IGF-I is associated with increased risk of breast cancer, as well as of other cancers. Most of circulating IGF-I is bound to an acid-labile subunit and to one of six insulin-like growth factor binding proteins (IGFBPs), among which the most important are IGFBP-3 and IGFBP-1. Polymorphisms of the IGF1 gene and of genes encoding for the major IGF-I carriers may predict circulating levels of IGF-I and have an impact on cancer risk. We tested this hypothesis with a case-control study of 807 breast cancer patients and 1588 matched control subjects, nested within the European Prospective Investigation into Cancer and Nutrition. We genotyped 23 common single nucleotide polymorphisms in IGF1, IGFBP1, IGFBP3 and IGFALS, and measured serum levels of IGF-I and IGFBP-3 in samples of cases and controls. We found a weak but significant association of polymorphisms at the 5' end of the IGF1 gene with breast cancer risk, particularly among women younger than 55 years, and a strong association of polymorphisms located in the 5' end of IGFBP3 with circulating levels of IGFBP-3, which confirms previous findings. Common genetic variation in these candidate genes does not play a major role in altering breast cancer risk in Caucasians.

Insulin-like growth factor-I (IGF-I) stimulates cell proliferation and can enhance the development of tumors in different organs. Epidemiologic studies have shown that an elevated level of circulating IGF-I is associated to increased risk of breast cancer as well as other cancers. Genetic variants affecting the release or biological action of growth hormone (GH), the main stimulator of IGF-I production, may predict circulating levels of IGF-I and have an effect on cancer risk. We tested this hypothesis with a large case-control study of 807 breast cancer patients and 1,588 matched control subjects nested within the European Prospective Investigation into Cancer and Nutrition. We genotyped 22 common single nucleotide polymorphisms in 10 genes involved in GH production and action (GHRH, GHRHR, SST, SSTR1-SSTR5, POU1F1, and GH1), and in parallel, we measured serum levels of IGF-I and IGFBP-3, its major binding protein, in samples of cases and controls. SST and SSTR2 polymorphisms showed weak but statistically significant associations with breast cancer risk. SSTR5 polymorphisms were associated with IGF-I levels, whereas one polymorphism in GHRHR and one in POU1F1 were associated with IGFBP-3 levels. Our conclusion is that common genetic variation in the GH synthesis pathway, as measured by single nucleotide polymorphisms selected in the present study, is not a major determinant of IGF-I and IGFBP-3 circulating levels, and it does not play a major role in altering breast cancer risk.

The relationship between fatty acids and breast cancer has been debated for long, because of the high frequency of breast cancer and the contradictory results from the numerous studies devoted to this issue. The present review includes case-control and prospective studies, according to specified methodological criteria, which estimated the exposure to monounsaturated fatty acids (MUFA) and n-6 and n-3 polyunsaturated fatty acids (PUFA) using dietary questionnaires or markers (plasma, erythrocytes, adipose tissue). The relationship between MUFA intake and breast cancer risk seems to depend on the contributing food : neutral or beneficial for vegetable oil, rather deleterious for animal products. Contrary to data from animal experiments, human studies do not show an increase of breast cancer risk with n-6 PUFA intake. Estimating the risk associated with alpha-linolenic acid appears difficult due to the incompleteness of food composition tables and studies on biomarkers remain few. The same applies to long-chain n-3 PUFA despite the suggestion of a decrease in risk, in agreement with animal studies. However, it is difficult in human to disentangle the effect of nutrient intake from that of contributing foods or even nutritional profile.

Exogenous n-3 polyunsaturated fatty acids (PUFA) and specially docosahexaenoic acid (DHA) have been previously reported to potentiate the efficacy of anticancer agents that generate an oxidative stress, such as anthracyclines, by enhancing the susceptibility of cell membranes to lipid peroxidation. Since lipid peroxidation has also been suggested to mediate anthracycline-induced heart failure, we designed a study aimed at investigating whether a DHA-enriched diet coupled with controlled oxidative conditions prevents or aggravates this serious side effect in vivo. Female Sprague-Dawley rats were submitted for at least 3 weeks to diet enriched in DHA, which was provided either as natural oil (sardine oil, experiment 1) or in a purified form (DHASCO, experiment 2). At the same time, to constrain the nutritional oxidative status, the anti-oxidant Vitamin E or the pro-oxidant menadione/sodium ascorbate redox mixture was added. Then, epirubicin was administered weekly at two cumulative doses, 9 mg x kg(-1) (experiment 1) or 15 mg x kg(-1) (experiment 2). Cardiotoxicity was assessed by electrocardiographic (ECG) and hemodynamic measurements, completed with histological examination. Epirubicin-induced dose-dependent mortality, alterations of hemodynamic parameters and histological damages, all features characterizing the occurrence of congestive heart failure. Moreover, the addition of anti- or pro-oxidant did not change the hemodynamics either at the lowest (experiment 1) or the highest dose (experiment 2). Similarly, the ECG measurements and histological examinations did not reveal any difference. DHA was actually incorporated, as evaluated through the adipose tissue fatty acid composition. All these observations indicated that the DHA-enriched diet, placed under controlled oxidative conditions, did not appear to prevent but neither to aggravate epirubicin-induced cardiotoxicity. These findings support the idea that DHA improves the anthracycline therapeutic index.

To determine whether the purified 9c,11t conjugated linoleic acid (CLA) isomer, the main dietary isomer, is biologically active on mammary tumor growth, we carried out a dietary intervention study designed to compare its effects with those of a mixture of CLA isomers on the incidence and growth of autochthonous mammary tumors induced by methylnitrosourea in rats. After the initiation step, rats were fed a sunflower oil-based diet (5%) and separated into three experimental groups supplemented with either a 1% homemade synthesized 9c,11t isomer, a 1% CLA isomer mixture, or free fatty acids prepared from sunflower oil for the control group. We found that, in the two CLA groups compared with the control group, CLA levels were about 30 times higher in mammary fat pads and about 10 times higher in tumor tissues. Compared with the control group, there was a 44% and 45% decrease in tumor mass per rat in the CLA mixture and the 9c,11t groups, respectively, at 20 wk of diet (P < 0.05). There was a nonsignificant trend for a decrease multiplicity in CLA groups compared with the control group, with a 30% and 35% decrease in the CLA mixture and the 9c,11t groups, respectively. Incidence and latency were not significantly different between the dietary groups. Although the effect was specifically restricted in reduction in tumor mass, we concluded that the main CLA isomer found in human diet has anticarcinogenic properties in experimental mammary carcinogenesis.

Experimental studies have indicated that n-3 fatty acids, including alpha-linolenic acid (18:3 n-3) and long-chain n-3 polyunsaturated fatty acids inhibit mammary tumor growth and metastasis. Earlier epidemiological studies have given inconclusive results about a potential protective effect of dietary n-3 polyunsaturated fatty acids on breast cancer risk, possibly because of methodological issues inherent to nutritional epidemiology. To evaluate the hypothesis that n-3 fatty acids protect against breast cancer, we examined the fatty acid composition in adipose tissue from 241 patients with invasive, nonmetastatic breast carcinoma and from 88 patients with benign breast disease, in a case-control study in Tours, central France. Fatty acid composition in breast adipose tissue was used as a qualitative biomarker of past dietary intake of fatty acids. Biopsies of adipose tissue were obtained at the time of surgery. Individual fatty acids were measured as a percentage of total fatty acids, using capillary gas chromatography. Unconditional logistic regression modeling was used to obtain odds ratio estimates while adjusting for age, height, menopausal status and body mass index. We found inverse associations between breast cancer-risk and n-3 fatty acid levels in breast adipose tissue. Women in the highest tertile of alpha-linolenic acid (18:3 n-3) had an odds ratio of 0.39 (95% confidence intervals [CI] = 0.19-0.78) compared to women in the lowest tertile (trend p = 0.01). In a similar way, women in the highest tertile of docosahexaenoic acid (22:6 n-3) had an odds ratio of 0.31 (95% CI = 0.13-0.75) compared to women in the lowest tertile (trend p = 0.016). Women in the highest tertile of the long-chain n-3/total n-6 ratio had an odds ratio of 0.33 (95% confidence interval = 0.17-0.66) compared to women in the lowest tertile (trend p = 0.0002). In conclusion, our data based on fatty acids levels in breast adipose tissue suggest a protective effect of n-3 fatty acids on breast cancer risk and support the hypothesis that the balance between n-3 and n-6 fatty acids plays a role in breast cancer., (Copyright 2001 Wiley-Liss, Inc.)

Background: The relationship between erythrocyte membrane fatty acids and postmenopausal breast cancer risk was analyzed previously only by retrospective studies, which suggested a protective effect of increased saturation index (SI), i.e., the ratio of membrane stearic to oleic acid. We investigated the relationships in a prospective study of hormones, diet, and prediagnostic breast cancer (the ORDET study) conducted in northern Italy., Methods: A total of 4052 postmenopausal women were followed for an average of 5.5 years; 71 cases of invasive breast cancer were identified. For each case subject, two matched control subjects were chosen randomly from among cohort members. The various fatty acids in erythrocyte membranes were measured as a percentage of total fatty acids. Conditional logistic regression analysis evaluated the association between membrane fatty acid composition and breast cancer risk. The SI, which is influenced by the activity of the enzyme delta 9 desaturase (Delta 9-d), was also investigated. All statistical tests were two-sided., Results: Oleic (highest versus lowest tertile of percentage of total fatty acids, odds ratio [OR] = 2.79; 95% confidence interval [CI] = 1.24 to 6.28) and monounsaturated fatty acids (highest to lowest tertile, OR = 5.21; 95% CI = 1.95 to 13.91) were positively associated with breast cancer risk. The SI (highest to lowest tertile, OR = 0.29; 95% CI = 0.13 to 0.64) was inversely associated with breast cancer risk. The analysis suggested an inverse association between total polyunsaturated fatty acids and breast cancer risk, but individual polyunsaturated fatty acids behaved differently. There was no association between saturated fatty acids and breast cancer risk., Conclusions: We have found that monounsaturated fats and SI in erythrocyte membranes are predictors of postmenopausal breast cancer. Both of these variables depend on the activity of the enzyme Delta 9-d. The dietary, metabolic, and hormonal factors acting on Delta 9-d expression and activity and, therefore, on patterns of fatty acid metabolism, should be further investigated as possible determinants of breast cancer.

We conducted a first pilot study on healthy women living in two countries with different dietary habits, Granada in the south of Spain and Malmö in the south of Sweden, in order to compare their levels of plasma phospholipid fatty acids, and to examine the relationship between the differences in food consumption. This study is part of a pilot study which is nested in the European Prospective Investigation into Cancer and Nutrition, a multi-centre prospective cohort study on diet, plasma concentrations of antioxidants and fatty acids, and markers of oxidative stress. Thirty-nine women in Granada and thirty-eight women in Malmö, aged 45-50 years (all pre-menopausal) were selected among the female participants in the cohorts from these two countries. Individual measurements of the women's habitual diet were obtained by a food frequency questionnaire. 24-hour diet recalls were used for the standardised measurement of diet at group level. Plasma phospholipid fatty acid composition was determined by capillary gas chromatography. We found a different fatty acid profile in plasma between the two populations, with higher mean levels of palmitic acid (16:0), palmitoleic acid (16:1) (n-7), oleic acid (18:1), alpha-linolenic acid (18:3) (n-3) and eicosapentaenoic acid (20:5) (n-3), and lower mean levels of stearic acid (18:0) in Malmö compared to Granada. Women in Malmö consumed more meat, alcoholic beverages and sugar, and less fish and shellfish than women in Granada. We conclude that the fatty acid composition in plasma phospholipids is different between women from the two European centres. For polyunsaturated fatty acids, differences were observed for (n-3) fatty acids. In relation to these differences, we observed that specific food intakes, particularly meat and fish, varied between the two centres.

Objective: To investigate the usefulness of serum carotenoids as biomarkers of fruit and vegetable consumption., Design: : Reproducibility study on three repeat measurements of serum carotenoids. Correlation analysis of carotenoids and dietary food intake, and regression analysis of potential predictive parameters for serum carotenoid levels., Setting: New York, USA., Subject: : Women participating in the New York Women's Health Study, a prospective study of sex hormones, diet and breast cancer. Forty-eight women with three repeat blood samples and 302 women having a blood sample and a dietary history questionnaire (including 47 subjects from the reproducibility study)., Results: Serum carotenoid concentrations were highly reproducible between one- and two-year repeat samples. Estimated fruit and vegetable consumption was positively correlated with serum carotenoid concentrations but correlation coefficients were low. Consumption of fruit was predictive for serum levels of beta-carotene, alpha-carotene and beta-cryptoxanthin, while vegetable consumption was predictive for serum beta-carotene, lutein, zeaxanthin and lycopene. Serum concentrations of cholesterol and triglycerides were predictive for serum carotenoids but adjustment for their levels had little or no influence on the correlation between fruit and vegetable consumption and serum carotenoid concentrations., Conclusions: One single serum measurement of alpha-carotene, beta-carotene and lutein can accurately rank subjects according to their usual serum level. Serum concentrations, however, correlate only moderately with estimated dietary intake of fruits or vegetables and should therefore be used with caution as biomarkers of fruit and vegetable intake.

We conducted a cross-sectional pilot study on healthy pre-menopausal women (aged 45-50 years) living in Granada, in the south of Spain (n = 39) and Malmö, in the south of Sweden (n = 38) in order to compare their plasma carotenoid levels and to investigate the relationship between the differences in food consumption. Plasma concentrations of six carotenoids were measured using high performance liquid chromatography, habitual diet (at individual level) was estimated by food frequency questionnaires and 24-hour diet recalls were used for standardised measurement of diet at group-level. We found that women in Granada consumed more fruit and vegetables than women in Malmö. Plasma concentrations of beta-cryptoxanthin, lycopene, zeaxanthin, total carotenoids and alpha-tocopherol were higher in Granada than in Malmö, although plasma concentrations of alpha-carotene and retinol were higher in Malmö. Both within and between study centres, consumption of fruit and vegetables correlated positively with plasma concentrations of different carotenoids. The study showed that differences in consumption of fruit and vegetables between the two European centres were reflected in plasma carotenoid concentrations.

Objective: We examined the reliability of the fatty acid composition of serum phospholipids in the New York University Women's Health Study, a prospective study of sex hormones, diet and breast cancer., Design: Non-fasting serum samples collected at three yearly visits, in 46 healthy women, and stored at -80 degrees C for 7-12 y, were included in the study. Serum phospholipid fatty acid composition was measured by capillary gas chromatography., Results: For the 20 individual fatty acids measured, the reliability coefficients were less than 0.50 for four, between 0.50 and 0.70 for nine, and greater than 0.70 for seven. Among the major fatty acids, arachidonic and alpha-linolenic acids had high reliability coefficients (0.71 and 0. 72, respectively), palmitic, oleic, linoleic, eicosapentaenoic and docosahexaenoic acids had intermediate coefficients (0.57, 0.69, 0. 62, 0.64 and 0.66, respectively), whereas stearic acid had the lowest coefficient (0.15). The reliability coefficients for total monounsaturated fats, omega-6 and omega-3 fatty acids were moderately high (0.66, 0.53 and 0.66, respectively), whereas the coefficients for total saturated fats and total polyunsaturated fats were low (0.31 and 0.43, respectively)., Conclusions: These results indicate that the fatty acid composition of serum phospholipids can be a useful tool in epidemiologic studies, although for most fatty acids a single determination is associated with some error in measurement that should be taken into account at the design and analysis stages. Storage for up to 12 y at -80 degrees C preserved polyunsaturated fatty acids from oxidation very well.

Data derived from experimental studies suggest that alpha-linolenic acid may have a protective effect in breast cancer. Observations obtained from epidemiological studies have not allowed conclusions to be drawn about a potential protective effect of dietary alpha-linolenic acid on breast cancer, possibly because of methodological issues. This case-control study conducted in an homogeneous population from a central area in France was designed to explore the hypothesis that alpha-linolenic acid inhibits breast cancer, using fatty acid levels in adipose breast tissue as a biomarker of past qualitative dietary intake of fatty acids. Biopsies of adipose breast tissue at the time of diagnosis were obtained from 123 women with invasive non-metastatic breast carcinoma. 59 women with benign breast disease served as controls. Individual fatty acids were analysed by capillary gas chromatography. An unconditional logistic regression model was used to obtain odds ratio estimates whilst adjusting for age, menopausal status and body mass index (BMI). No association was found between fatty acids (saturates, monounsaturates, long-chain polyunsaturates n-6 or n-3) and the disease, except for alpha-linolenic acid which showed an inverse association with the risk of breast cancer. The relative risk of breast cancer for women in the highest quartile of adipose breast tissue alpha-linolenic acid level was 0.36 (95% confidence interval=0.12-1.02) compared with those in the lowest quartile (P trend=0.026), suggesting a protective effect of alpha-linolenic acid in the risk of breast cancer. The effects of dietary alpha-linolenic on the risk of breast cancer warrant further study.

The study of the relationship between dietary intake of fatty acids and the risk of breast cancer has not yielded definite conclusions with respect to causality, possibly because of methodological issues inherent to nutritional epidemiology. To evaluate the hypothesis of possible protection of n-3 polyunsaturated fatty acids (PUFA) against breast cancer in women, we examined the fatty-acid composition of phospholipids in pre-diagnostic sera of 196 women who developed breast cancer, and of 388 controls matched for age at recruitment and duration of follow-up, in a prospective cohort study in Umeâ, northern Sweden. Individual fatty acids were measured as a percentage of total fatty acids, using capillary gas chromatography. Conditional logistic-regression models showed no significant association between n-3 PUFA and breast-cancer risk. In contrast, women in the highest quartile of stearic acid had a relative risk of 0.49 (95% confidence interval, 0.22-1.08) compared with women in the lowest quartile (trend p = 0.047), suggesting a protective role of stearic acid in breast-cancer risk. Besides stearic acid, women in the highest quartile of the 18:0/18:1 n-9c ratio had a relative risk of 0.50 (95% confidence interval, 0.23-1.10) compared with women in the lowest quartile (trend p = 0.064), suggesting a decrease in breast-cancer risk in women with low activity of the enzyme delta 9-desaturase (stearoyl CoA desaturase), which may reflect an underlying metabolic profile characterized by insulin resistance and chronic hyper-insulinemia., (Copyright 1999 Wiley-Liss, Inc.)

Experimental studies indicated that long-chain polyunsaturated fatty acids may increase sensitivity of mammary tumours to several cytotoxic drugs. To evaluate this hypothesis in breast cancer, we have prospectively studied the association between levels of fatty acids stored in breast adipose tissue and the response of the tumour to chemotherapy in 56 patients with an initially localized breast carcinoma. Adipose breast tissue was obtained at the time of biopsy, and individual fatty acids were measured as a percentage of total fatty acids using capillary gas chromatography. Patients then received primary chemotherapy, combining mitoxantrone, vindesine, cyclophosphamide and 5-fluorouracil every 4 weeks. Tumour size was reassessed after three cycles of chemotherapy. Tumour response was evaluated according to World Health Organization criteria. Complete or partial response to chemotherapy was achieved in 26 patients (47%). Level of n-3 polyunsaturated fatty acids in adipose tissue was higher in the group of patients with complete or partial response to chemotherapy than in patients with no response or with tumour progression (P < 0.004). Among n-3 polyunsaturated, only docosahexaenoic acid (22:6n-3) was significantly associated with tumour response (P < 0.005). In a logistic regression analysis taking into account age, body mass index and tumour size, 22:6 n-3 level proved to be an independent predictor for chemosensitivity (P = 0.03). These results suggest that, in breast cancer, 22:6 n-3 may increase the response of the tumour to the cytotoxic agents used.

Exogenous polyunsaturated fatty acids modulate the cytotoxic activity of anti-cancer drugs. In this study, we examined whether lipid peroxidation is a potential mechanism through which fatty acids enhance drug cytotoxicity. We measured cell viability in the human breast cancer cell line MDA-MB-231 exposed to doxorubicin in the presence of non-cytotoxic concentrations of various polyunsaturated fatty acids for 6 days. To determine the role of lipid peroxidation, the hydroperoxide level was measured in cell extracts. Among all polyunsaturated fatty acids tested, docosahexaenoic acid (DHA, 22:6n-3) was the most potent in increasing doxorubicin cytotoxicity: cell viability decreased from 54% in the presence of 10(-7) M doxorubicin alone to 21% when cells were incubated with doxorubicin and DHA. After addition of an oxidant system (sodium ascorbate/2-methyl-1,4-naphthoquinone) to cells incubated with doxorubicin and DHA, cell viability further decreased to 12%. Cell hydroperoxides increased commensurately. The effect of DHA on doxorubicin activity and lipid hydroperoxide formation was abolished by a lipid peroxidation inhibitor (dl-alpha-tocopherol) or when oleic acid (a non-peroxidizable fatty acid) was used in place of DHA. No effect was observed with mitoxantrone, a drug with a low peroxidation-generating potential. Thus, DHA may increase the efficacy of oxyradical-producing drugs through a mechanism involving a generation of lipoperoxides. This may lead in vivo to a modulation of tumor cell chemosensitivity by DHA and oxidant agents.

Despite considerable methodological advances, ideal parameters relating to the in vitro assessment of lipoprotein oxidizability are lacking. In this study, some of the more common parameters of lipid peroxidation were measured in 30 plasma samples. The following parameters were determined: conjugated dienes (method 1), reaction of lipid hydroperoxides with a methylene blue derivative (method 2), oxidation of iodide to triiodide (method 3) and an iodometric assay based on the same chemistry but modified to correct for unspecific interferences (method 4). Alpha-Tocopherol in plasma was assayed by high-pressure liquid chromatography. In addition, LDL was isolated from plasma and the susceptibility of individual LDL preparations towards copper-initiated oxidation was characterized. The amount of lipid hydroperoxides found in fresh plasma samples obtained from apparently healthy humans was dependent on the method used for the assessment. Lipid hydroperoxides measured by method 2 were: 8.6 +/- 5.8 mu M, by method 3: 5.8 +/- 1.9 mu M and by method 4: 4.2 +/- 2.7 mu M. Mean values of conjugated dienes (method 1) were 84.6 +/- 20.9 mu M; The content of alpha-tocopherol in plasma was 23.6 +/- 3.9 mu M. Despite the differences in absolute values, a statistically significant correlation was found between values obtained by methods 1, 2 and 3, but not by method 4. An inverse relationship has been observed between the lipid hydroperoxide content in plasma obtained with method 4 and two parameters of LDL oxidation (diene concentration, rate of diene formation) but not with the lag time. Our data suggest that--among the photometric methods evaluated--method 4 might be the most specific for the measurement of plasma (and lipoprotein associated) lipid hydroperoxides.

To assess the part that host fatty-acid supply and tumor-specific fatty-acid utilization contribute to the membrane lipid composition of tumor tissue, intra-individual comparisons of membrane fatty acids were carried out between breast-carcinoma tissue and non-tumorous breast tissue adjacent to the tumor and taken as reference. Phospholipids were purified by thin-layer chromatography from tumor biopsies obtained from 59 patients with a localized presentation of breast cancer, and fatty acids analyzed by capillary gas chromatography. Elevated levels of palmitic, palmitoleic and arachidonic acids, along with a low level of linoleic acid, were observed in membrane phospholipids of tumors with poor histoprognostic grade. The level of mono-unsaturated fatty acids was higher, and the level of essential fatty acids was lower in the tumor than in the reference breast tissue. Fatty-acid-desaturating activity was not detectable in tumors. A positive relationship was observed among patients for most of the fatty acids between carcinoma and non-tumorous breast tissue, except for mono-unsaturated and essential fatty-acid levels, which were not correlated between both tissues. These data suggest that mechanisms specifically related to malignant transformation and tumor progression influence the membrane fatty-acid profile of breast carcinoma. Fatty acid supply to the tumor, possibly modified by metabolic conditions related to the host, also seems to play a decisive role in this composition.

Epidemiological studies suggest a causal relationship of dietary polyunsaturated fatty acids (PUFA's) with the morbidity and mortality from breast cancer. In order to reveal possible underlying mechanisms of these findings, we studied the influence of n-3 and n-6 PUFA's in comparison to oleic acid on the proliferation of well characterized estrogen dependent (MCF-7, ZR-75, T-47-D) and estrogen independent (MDA-MB-231, HBL-100) breast cancer cells in culture. The cell growth inhibitory effect was related to the formation of lipid peroxidation products. Normal human skin fibroblasts served as a control. In fibroblasts, the addition of 20 micrograms/ml of exogenous fatty acids either had no effect or caused an insignificant increase of proliferation. Similar results were obtained with MCF-7 cells. In all other breast cancer cell types, n-3 long-chain PUFA's, eicosapentaenoic and docosahexaenoic acids, were the most effective fatty acids in arresting the cell growth. Alpha-linolenic and gamma-linolenic acid exerted a variable effect on cell proliferation depending on the cell line investigated. Oleic acid significantly stimulated the proliferation of hormone-independent breast cancer cells while it had no effect on the proliferation of hormone-dependent cells. Viability studies by trypan blue excretion indicated that the arrest in cell growth was not due to major cytotoxic effects. The addition of PUFA's to breast cancer cells caused a significant increase in the formation of conjugated dienes and lipid hydroperoxides in the cellular lipids; their content was significantly correlated with the capacity of arresting cell growth. In contrast, the addition of PUFA's to fibroblasts did not increase lipid hydroperoxide formation. The addition of Vitamin E to cancer cells at a concentration of 10 microM to the PUFA-supplemented medium almost completely restored cell growth. Our data indicate that PUFA's significantly interfere with cell proliferation of breast cancer cells in vitro due to the formation of oxidation products. In addition to that, there must be other factors involved, most probably related to the differential metabolism of PUFA's in tumor cells. Our findings may have some impact on treatment and prevention of breast cancer.

The association between the levels of various fatty acids in adipose breast tissue and the emergence of visceral metastases was prospectively studied in a cohort of 121 patients with an initially localised breast cancer. Adipose breast tissue was obtained at the time of initial surgery, and its fatty acid content analysed by capillary gas chromatography. A low level of alpha-linolenic acid (18:3n-3) in adipose breast tissue was associated with positive axillary lymph node status and with the presence of vascular invasion, but not with tumour size or mitotic index. After an average 31 months of follow-up, 21 patients developed metastases. Large tumour size, high mitotic index, presence of vascular invasion and low level of 18:3n-3 were single factors significantly associated with an increased risk of metastasis. A Cox proportional hazard regression model was used to identify prognostic factors. Low 18:3n-3 level and large tumour size were the two factors predictive of metastases. These results suggest that host alpha-linolenic acid has a specific role in the metastatic process in vivo. Further understanding of the biology of this essential fatty acid of the n-3 series is needed in breast carcinoma.