Glycation is the non-enzymatic glycosylation of sugars with proteins, lipids and DNA that lead to the production of reactive metabolites called advanced glycation end products (AGE's). Glycation occurs whenever excessive sugars are available and drives many of the complications associated with diabetes. Tumors are also characterized by high glucose levels which fuels high rate glycolysis for energy production (known as the Warburg effect). Project SuGAR is a community based research database focusing on Sea Island families affected by type-2 diabetes. The goal of this study is to use this unique resource and its banked biological samples to explore if high AGE metabolite levels predict cancer incidence and mortality in a background of normal sugar levels (non-diabetic Sea Islanders) and high sugar levels (Sea Islanders with type-2 diabetes). Recent studies have led to our hypothesis that "elevated levels of AGE's promote cancer disparity through the activation of the AGE-RAGE signaling axis to promote inflammation".
Specific aim 1 of this study relates secretory AGE levels to cancer incidence and mortality in Project SuGAR participants with and without type-2 diabetes. This initial study represents the first analysis of cancer incidence and mortality as well as cancer/diabetes co-morbidity within the Sea Island population of South Carolina. Ages mediate many of their deleterious effects by functioning as ligands for the receptor for advanced glycation end products (RAGE). RAGE is an oncogenic transmembrane receptor which promotes inflammatory responses. Secreted RAGE (sRAGE) is a splice variant of RAGE which can act as a decoy domain receptor to decrease AGE cellular binding of RAGE. Higher sRAGE levels are associated with favorable outcome in many tumor types.
Specific aim 2 will measure sRAGE as well as inflammatory marker expression with which to relate to AGE levels and cancer incidence and mortality within the Sea Island population of South Carolina. Understanding biological links between diabetes and cancer is particularly confounded by the lack of information on potential shared risk factors. By developing the existing datasets contained within Project SuGAR to include cancer incidence and mortality rates, we will develop a unique resource to not only address these confounding factors but to analyze racial specific factors promoting disparity in diabetes, cancer and comorbidity for the two diseases. Additionally, the AGE-RAGE-inflammation signaling axis may have potential impact as prognostic/diagnostic markers to guide treatment strategies for aggressive disease. It may also define a novel area of therapeutic intervention which may be developed as clinical trials within Project SuGAR and the Sea Island community. African Americans have increased risk to develop and ultimately die of both diabetes and cancer. The development of the Project SuGAR resource and a greater understanding of the role of glycation in cancer have the potential to significantly impact survival and quality of life within this population.
The development of the Project SuGAR resource and defining that elevated levels of AGE metabolites may represent a metabolic susceptibility difference driving cancer disparity has the potential to significantly impact survival and quality f life within African Americans. The addition of cancer incidence and mortality data to the Project SuGAR database will provide a platform for collaborative basic, translational and epidemiological studies with which to assess basic cancer research in cancer health disparities. Additionally, the AGE-RAGE- inflammation signaling axis may have potential impact as prognostic/diagnostic markers to guide treatment strategies for aggressive disease and as novel avenues for therapeutic development which may be developed into clinical trials within Project SuGAR and the Sea Island community.
|Foster, Dion; Spruill, Laura; Walter, Katherine R et al. (2014) AGE metabolites: a biomarker linked to cancer disparity? Cancer Epidemiol Biomarkers Prev 23:2186-91|