PURPOSE: The protective effect of Allium vegetables against carcinogenesis has been reported in experimental studies particularly focusing on the gut. Therefore, we conducted a hospital-based matched case-control study to explore the association between dietary Allium consumption and risk of breast cancer among Iranian women in northwest Iran. METHODS: A validated, quantitative, food frequency questionnaire was completed in 285 women (aged 25–65 years old) newly diagnosed with histopathologically confirmed breast cancer (grade II, III or clinical stage II, III) in Tabriz, northwest Iran, and the completed questionnaires were included in an age- and regional-matched hospital based-control study. The odds ratios (ORs) and 95% confidence intervals (95% CI) were estimated using conditional logistic regression models. RESULTS: Multivariate analysis showed that there was a negative association between the consumption of raw onion and risk of breast cancer after adjustment for covariates (OR, 0.63; 95% CI, 0.40–1.00); however, this association was insignificant. On the other hand, there was a positive association between consumption of cooked onion and risk of breast cancer, after adjustment for covariates (OR, 1.54; 95% CI, 1.02–2.32). However, reduced risk of breast cancer was associated with higher consumption of garlic and leek with adjusted ORs of 0.41 (95% CI, 0.20–0.83) and 0.28 (95% CI, 0.15–0.51), respectively. CONCLUSION: Our findings suggest that high consumption of certain Allium vegetables, in particular garlic and leek, may reduce the risk of breast cancer, while high consumption of cooked onion may be associated with an increased risk of breast cancer.
Allium* ; Breast Neoplasms* ; Breast* ; Carcinogenesis ; Case-Control Studies* ; Female ; Garlic ; Hand ; Humans ; Iran ; Logistic Models ; Multivariate Analysis ; Odds Ratio ; Onions ; Prebiotics ; Vegetables*

Prebiotics modulate microbial composition and ensure a healthy gastrointestinal tract environment that can prevent colon cancer development. These natural dietary compounds are therefore potential chemopreventive agents. Thirty Sprague-Dawley rats (4 months old) were experimentally treated with procarcinogen dimethylhydrazine to induce colon cancer development. The rats were randomly assigned to three groups: a control group (CG), a group treated with dimethylhydrazine (DMH), and a group given DMH and inulin, a prebiotic (DMH+PRE). The effects of inulin on the activities of bacterial glycolytic enzymes, short-chain fatty acids, coliform and lactobacilli counts, cytokine levels, and cyclooxygenase-2 (COX-2) and transcription nuclear factor kappa beta (NFkappaB) immunoreactivity were measured. Inulin significantly decreased coliform counts (p < 0.01), increased lactobacilli counts (p < 0.001), and decreased the activity of beta-glucuronidase (p < 0.01). Butyric and propionic concentrations were decreased in the DMH group. Inulin increased its concentration that had been reduced by DMH. Inulin decreased the numbers of COX-2- and NFkappaB-positive cells in the tunica mucosae and tela submucosae of the colon. The expression of IL-2, TNFalpha, and IL-10 was also diminished. This 28-week study showed that dietary intake of inulin prevents preneoplastic changes and inflammation that promote colon cancer development.
Animals ; Bacterial Proteins/genetics/metabolism ; Colon/enzymology ; Colonic Neoplasms/chemically induced/*drug therapy/metabolism ; Colony Count, Microbial ; Cyclooxygenase 2/genetics/metabolism ; Cytokines/blood/genetics ; Diet ; Dietary Supplements/analysis ; Dimethylhydrazines/toxicity ; Enterobacteriaceae/drug effects/physiology ; Fatty Acids, Volatile/genetics/metabolism ; Female ; Gene Expression Regulation/drug effects ; Inulin/administration & dosage/*metabolism ; Lactobacillaceae/drug effects/physiology ; Male ; NF-kappa B/genetics/metabolism ; Prebiotics/*analysis ; Rats ; Rats, Sprague-Dawley