Omega-3 fatty acids decrease prostate cancer progression associated with an anti-tumor immune response in eugonadal and castrated mice.

BACKGROUND: Several lines of evidence suggest effects of dietary fat on prostate cancer (PCa) development and progression. Targeting omega (ω)-3:ω6 fatty acids (FA) ratio could be beneficial against PCa by favorably modulating inflammation. Here, we studied the effects of ω3- and ω6-enriched diets on prostate tumor growth and inflammatory response in androgen-deprived and non-deprived conditions. METHODS: Immune-competent eugonadal and castrated C57BL/6 mice were injected with TRAMP-C2 prostate tumor cells and daily fed with ω3- or ω6-enriched diet. FA and cytokine profiles were measured in blood and tumors using gas chromatography and multiplex immunoassay, respectively. Immune cell infiltration in tumors was profiled by multicolor flow cytometry. RESULTS: ω3-enriched diet decreased prostate TRAMP-C2 tumor growth in immune-competent eugonadal and castrated mice. Cytokines associated with Th1 immune response (IL-12 [p70], IFN-γ, GM-CSF) and eosinophil recruitment (eotaxin-1, IL-5, and IL-13) were significantly elevated in tumors of ω3-fed mice. Using in vitro experiments, we confirmed ω3 FA-induced eotaxin-1 secretion by tumor cells and that eotaxin-1 secretion was regulated by androgens. Analysis of immune cell infiltrating tumors showed no major difference of immune cells' abundance between ω3- and ω6-enriched diets. CONCLUSIONS: ω3-enriched diet reduces prostate tumor growth independently of androgen levels. ω3 FA can inhibit tumor cell growth and induce a local anti-tumor inflammatory response. These findings warrant further examination of dietary ω3's potential to slow down the progression of androgen-sensitive and castrate-resistant PCa by modulating immune cell function in tumors.

Quantifying Long-Term Changes in Lung Function and Exacerbations after Initiation of Azithromycin in Cystic Fibrosis.

Rationale: In cystic fibrosis, information on the efficacy of azithromycin past 12 months of treatment is still scarce.Objectives: The study sought to quantify the changes in lung function and the number of intravenous antibiotic courses (IVACs) after initiation of azithromycin in patients included in the French Cystic Fibrosis Registry.Methods: The study followed 1,065 children and 990 adults from 2 years before to 5 years after long-term azithromycin treatment initiated between 2001 and 2011. Mixed change-point models were used to quantify the changes in the forced expiratory volume (FEV) in 1 second and the yearly number of IVACs.Results: In the year of treatment initiation, the mean FEV was significantly higher than expected (+1.6%, P = 0.007 in children; +1.3%, P = 0.02 in adults). The decline of the FEV over time was less marked after than before treatment initiation (slope difference = +0.7% per year [P = 0.03] in children and +0.6% per year [P = 0.06] in adults). The mean increase in the yearly number of IVACs was lower after than before treatment initiation. The rate ratio quantifying the effect on the mean increase was 0.93 (95% confidence interval = [0.88-0.99]; P = 0.02) in children and 0.95 (95% confidence interval = [0.90-1.01]; P = 0.08) in adults.Conclusions: In children, long-term azithromycin treatment was associated with immediate and sustained beneficial changes in lung function and sustained beneficial changes in the frequency of pulmonary exacerbations. In adults, it was associated with immediate beneficial changes in lung function.