Nutrition Derived Advanced Glycation End Products Are Bio-Social Determinants of Health That Inform on Cancer Disparities

Objectives Through their ability to perpetuate a reactive stroma, the objective was to define the increased nutritional bioavailability of advanced glycation end products (AGEs) as a pro-tumorigenic consequence of interrelated health inequity risk factors that can influence ancestry specific tumor biology. Methods In vivo, ex vivo, and in vitro models were used to define the molecular effects of nutrition associated AGEs on the ancestry specific tumor microenvironment and tumor growth. Results The PI’s work provides the first in vivo evidence supporting an oncogenic role for AGEs. In mouse allograft models, both the chronic consumption of AGEs and pre-treatment with AGE bound peptide (p\u3c 0.0001) increased prostate tumor growth. In spontaneous tumor models, chronic AGE consumption caused rapid disease progression through prostate intra-epithelial neoplasia (p=0.049) to adenocarcinoma and metastatic disease. Mechanistically, AGEs recapitulated a regulatory program of ‘activated’ stroma similar to that observed in African American prostate tumors. Specifically, increased AGE bioavailability caused receptor for AGE (RAGE) dimerization in resident PCa fibroblasts leading to their activation and the downregulation of matrix regulatory proteins leading to rapid tumor progression. Conclusions When social and biological determinants of health are compromised it may increase nutritional exposure to AGEs and perpetuate a vicious cycle of AGE formation, bioavailability, and pathogenicity. As bio-social determinants of health, AGEs may represent informative and/or functional biomarkers that can be utilized across transdisciplinary studies to address the enduring complexities of cancer disparity

MicroRNA-510 mediated negative regulation of Caveolin-1 in fibroblasts promotes aggressive tumor growth

IntroductionIn the US, despite the recent decline in breast cancer deaths, a persistent mortality disparity exists between black and white women with breast cancer, with black women having a 41% higher death rate. Several studies are now reporting that racial disparities can exist independent of socioeconomic and standard of care issues, suggesting that biological factors may be involved. Caveolin-1 (Cav1) loss in the tumor stromal compartment is a novel clinical biomarker for predicting poor outcome in breast cancer including triple negative subtype, however the mechanism of Cav1 loss is unknown. We previously identified miR-510-5p as a novel oncomir and propose here that the high levels observed in patients is a novel mechanism leading to stromal Cav1 loss and worse outcomes.MethodsCav1 was identified as a direct target of miR-510-5p through luciferase, western blot and qPCR assays. Stromal cross talk between epithelial cells and fibroblasts was assessed in vitro using transwell co-culture assays and in vivo using xenograft assays.ResultsWe found that Cav1 is a direct target of miR-510-5p and that expression in fibroblasts results in an ‘activated’ phenotype. We propose that this could be important in the context of cancer disparities as we also observed increased levels of circulating miR-510-5p and reduced levels of stromal Cav1 in black women compared to white women with breast cancer. Finally, we observed a significant increase in tumor growth when tumor cells were co-injected with miR-510-5p expressing cancer associated fibroblasts in vivo.ConclusionWe propose that miR-510-5p mediated negative regulation of Cav1 in fibroblasts is a novel mechanism of aggressive tumor growth and may be a driver of breast cancer disparity

Prevention of the Oncogenic Effects of Lifestyle-Associated Advanced Glycation End-Products (AGEs) via Regular Physical Activity

Interrelated lifestyle factors such as a sedentary habit, obesity and diets consisting of highly processed, high protein and fat containing foods, contribute to the accumulation of reactive metabolites known as advanced glycation end-products (AGEs). AGE pathogenic effects are mediated through modification of protein function, genetic fidelity, stress responses, and aberrant cellular signaling. For the first time, this study examined the effects of dietary AGE consumption on cancer progression in vivo and assessed physical activity (PA) as a potential intervention to reduce dietary AGE mediated effects. Given the links between lifestyle and AGEs, we propose that a diet high in AGEs can accelerate prostate cancer progression and severity which can be negated by regular PA. We found that chronic consumption of AGEs promotes prostate tumor growth and progression in vivo using syngeneic xenograft and spontaneous prostate cancer mouse models. Mechanistically, the stromal function of the transmembrane receptor for AGE (RAGE) was found to be a key substrate and effector of dietary-AGE tumorigenic function. Dietary AGE mediated activation of RAGE promoted a pro-tumorigenic microenvironment through the activation of cancer associated fibroblasts (CAFs) and macrophage polarization. Regular PA intervention by mice inhibited dietary-AGE induced tumor growth and progression. These results identify AGE content in food as a ubiquitous pro-tumorigenic consequence of lifestyle. They serve to focus future studies on the therapeutic potential of reducing AGEs through intervention and pharmacological strategies

Pubertal exposure to dietary advanced glycation end products disrupts ductal morphogenesis and induces atypical hyperplasia in the mammary gland

Abstract Background Advanced glycation end products (AGEs) are reactive metabolites intrinsically linked with modern dietary patterns. Processed foods, and those high in sugar, protein and fat, often contain high levels of AGEs. Increased AGE levels are associated with increased breast cancer risk, however their significance has been largely overlooked due to a lack of direct cause-and-effect relationship. Methods To address this knowledge gap, FVB/n mice were fed regular, low AGE, and high AGE diets from 3 weeks of age and mammary glands harvested during puberty (7 weeks) or adulthood (12 weeks and 7 months) to determine the effects upon mammary gland development. At endpoint mammary glands were harvested and assessed histologically (n ≥ 4). Immunohistochemistry and immunofluorescence were used to assess cellular proliferation and stromal fibroblast and macrophage recruitment. The Kruskal–Wallis test were used to compare continuous outcomes among groups. Mammary epithelial cell migration and invasion in response to AGE-mediated fibroblast activation was determined in two-compartment co-culture models. In vitro experiments were performed in triplicate. The nonparametric Wilcoxon rank sum test was used to compare differences between groups. Results Histological analysis revealed the high AGE diet delayed ductal elongation, increased primary branching, as well as increased terminal end bud number and size. The high AGE diet also led to increased recruitment and proliferation of stromal cells to abnormal structures that persisted into adulthood. Atypical hyperplasia was observed in the high AGE fed mice. Ex vivo fibroblasts from mice fed dietary-AGEs retain an activated phenotype and promoted epithelial migration and invasion of non-transformed immortalized and tumor-derived mammary epithelial cells. Mechanistically, we found that the receptor for AGE (RAGE) is required for AGE-mediated increases in epithelial cell migration and invasion. Conclusions We observed a disruption in mammary gland development when mice were fed a diet high in AGEs. Further, both epithelial and stromal cell populations were impacted by the high AGE diet in the mammary gland. Educational, interventional, and pharmacological strategies to reduce AGEs associated with diet may be viewed as novel disease preventive and/or therapeutic initiatives during puberty

Additional file 1 of Pubertal exposure to dietary advanced glycation end products disrupts ductal morphogenesis and induces atypical hyperplasia in the mammary gland

Additional file 1. Fig. S1 Individual mouse weight (A) and weekly food consumption (B) for each of the diet groups (n ≥ 4); regular (triangles), low AGE (circles) and high AGE (squares). (C) Quantitative ELISA of AGE levels in the serum of mice fed a regular, low AGE and high AGE diet (n ≥ 3) for 4 weeks compared to baseline levels. Values are mean ± SD