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Several environmental factors, such as ionizing radiation and some occupational aspects, as well as habits like smoking and alcohol consumption, are related to salivary tumorigenesis. Both acinar and ductual cells may be involved in the origin of salivary gland tumours. Even though laboratory and epidemiological evidence indicates that diet and nutritional habits may modulate the tumorigenesis at different sites, little is known about this effect on salivary glands, mainly in regard to dietary lipids. However, the fact that monounsaturated fatty acids behave as protumorigenic and, on the contrary, certain polyunsaturated fatty acids exert beneficial effects, demonstrated on breast, colon and even oral cancer, gives support to our hypothesis. The suggested relationship between environmental and nutritional factors, mainly dietary lipids, and salivary gland cancer constitutes the aim of the present work. Descriptors: salivary glands; tumours; diet; dietary lipids; environmental factors, Introduction Major and minor salivary glands are sites in which both benign and malignant tumours may develop. Salivary gland cancer is a rare disease with a largely unknown origin (Muscat [...]

Abstract: We investigated the effects of certain dietary polyunsaturated fatty acids (PUFAs) and related eicosanoids on the growth and metastasis formation of a murine mammary gland adenocarcinoma. Salvia hispanica (ChO) and Carthamus tinctorius (SaO) vegetable oil sources of ω-3 and -6 PUFAs and a commercial diet as control (CO), were used. We analysed fatty acids of neoplastic cells (NC) membranes by GLC; the eicosanoids 12- HETE and 12-HHT (LOX and COX metabolites) by HPLC and apoptosis and T-lymphocyte infiltration by flow cytometry and microscopy. NC from ChO groups showed lower levels of arachidonic acid and of both eicosanoids compared to SaO and CO (p<0.05). The ChO diet decreased the tumor weight and metastasis number (p<0.05). Apoptosis and T-lymphocyte infiltration were higher and mitosis decreased with respect to the other diets (p<0.05). Present data showed that ChO, an ancient and almost unknown source of ω-3, inhibits growth and metastasis in this tumor model. [Copyright &y& Elsevier]

Abstract: The purpose of this work was to analyze the effect of diets that contain several oils whose composition in fatty acids were different, on the kinetic parameters of the gamma-glutamyltranspeptidase (GGTP) and the lipoperoxidation of the epididymis because GGTP controls the level of the glutathione that is an molecule that regulates the level of oxidation protecting the maturation and survival of sperm in the lumen of the epididymis. The caput portion of the epididymis was chosen because the epithelium of this segment synthesizes GGTP. Weaned BALB-c mice were fed a commercial or semi-synthetic diet that contained 5% added olein. The mice were maintained on corn oil or fish oil diet for the first 4–8 months of age. The kinetic variables of the GGTP enzyme, analyzed by means of multiple regression analysis using dummy variables, showed that values were similar in olein and corn oil samples, whereas in samples from the fish oil fed group the enzyme behaved as that in animals maintained on commercial diets. Although there were no variations in maximum velocity (V m) of the enzyme, the K m value, was greater (P <0.0001) for the mice fed the olein and corn diets. These groups contained greater percentages of the monounsaturated fatty acids, palmitoleic (16:1 n-7) and oleic acid, 18:1 n-9. Similarly, the amount of lipid peroxidation was also greater in the olein and corn oil groups with respect to commercial and fish groups. The significant increment in K m of GGTP in the olein and corn groups was correlated with greater amount of monounsaturated fatty acids and lipid peroxidation in the epididymis. In conclusion, modifications of dietary lipid sources differentially modulated the epididymis tissue fatty acid profile, lipid peroxidation amounts, and the K m of GGTP. These effects may alter the metabolism of the natural substrate of GGTP, glutathione, a tripeptide with a powerful antioxidant activity, which is necessary in maintaining the oxidative state of the sperm microenvironment, thereby favoring maturation of the male gametes. [Copyright &y& Elsevier]

Abstract: Dietary arachidonic acid (AA) and eicosanoids influence neoplastic cell (NC) growth, differentiation and apoptosis. Plasma membrane fatty acid and cyclooxygenase (COX) and lipoxygenase (LOX) products were investigated in lung alveolar carcinoma cells from mice fed on different diets. Two groups were fed on a basic diet plus 6% of: corn oil (rich in 18:2n-6; CO) and on olein oil (rich in 18:1n-9; O), respectively. Control group (C) received commercial diet. NC fatty acids were analyzed by GLC, and apoptosis by flow cytometry and microscopy. In NC from CO group AA levels and LOX metabolites were increased, whereas COX metabolites decreased. NC from CO compared to O group diet showed a higher count of apoptosis and increased LOX:COX ratio. High levels of AA and decreased COX eicosanoids has been involved in anti-tumoral mechanisms by increasing tumor cell apoptosis. Present data emphasizes the implications of the dietary fatty acids on the neoplastic process in this tumoral model. [Copyright &y& Elsevier]

The essential fatty acid deficiency (EFAD) is a metabolic condition related to cancer development. We studied the effect of eicosapentaenoic acid (EPA, 20:5 n-3) and eicosatrienoic acid (ETA, 20:3 n-9), an essential fatty acid (EFA) and non-EFA respectively, on tumour cells parameters linked to tumour progression and metastases. Human tumour cell lines (T-24 from urothelium, MCF-7 from breast and HRT-18 from colon) were used. EPA showed an anti-proliferative effect on the three lines. ETA showed the following effects: in T-24, the lipid peroxidation was decreased and E-cadherin was undetectable; in MCF-7, increased E-cadherin expression enhanced the lipid peroxidation and decreased cell proliferation; on HRT-18, the E-cadherin expression and lipid peroxidation diminished, whereas cell proliferation was increased. In conclusion, EFA (20:5 n-3) exhibited beneficial effects, whereas unusual ETA showed an opposite effect on some tumour parameters. The possible riskiness of EFA-deprivation, along with the potential of EFA as natural nutrapeutic products for human tumour prevention and treatment, makes EFA worthy of further consideration. [Copyright &y& Elsevier]