Diabetes and cancer: Epidemiology and potential mechanisms

Abstract

Type 2 diabetes mellitus is an independent risk factor for cancer such as pancreatic, liver, colorectal and breast cancer. In addition, diabetes decreases the risk of prostate cancer. These associations have been found in numerous epidemiological studies, among them several prospective cohorts. However, such studies do not prove causality of the association and cannot exclude inadequate correction for known confounders (e.g. visceral fat) or the influence of unknown confounders. Thus, it is unclear whether the cancer risk is increased by the causes (e.g. the metabolic syndrome), the metabolic consequences (e.g. hyperglycaemia) or the therapy of diabetes; a question which is of major importance for therapeutic guidelines. Identification of the potential mechanisms by which the diabetes or its therapy accelerates or inhibits the development of cancer will help answering the question by providing biological plausibility. This review will summarize the evidence supporting the association of cancer and type 2 diabetes and discuss its potential causes.

Translating the Science of Aging into Therapeutic Interventions

“…It might be possible to alleviate these disorders with agents that target fundamental aging processes. For example, obesity and diabetes are associated with early onset of ageassociated disorders, including frailty, sarcopenia, atherosclerosis, vascular dysfunction, early menopause, cognitive impairment, dementia, and cancers (Tchkonia et al 2010;De Felice and Ferreira 2014;Joost 2014). Survivors of childhood cancers who had been treated with chemotherapy or radiation sometimes develop frailty, sarcopenia, diabetes, cardiac disease, cognitive impairment, and unrelated second malignancies by mid-adulthood (Hudson et al 2013;Ness et al 2014).…”

Green Tea and Its Extracts in Cancer Prevention and Treatment

“…An increased risk for prostatic cancer correlates with reduced physical activity [183], high BMI [184,185] and diabetes mellitus [186]; farming has been published as a risk factor (although pesticide use is reported as protective; [187]), and lycopene from tomatoes [181,188], catechins, isoflavons and curcumin [7] are probably protective.…”

Oriented Physical Exercise and Sports Nutrition and the Risk of Growth of Tumours

“…The oxidative stress is caused by the unbalance between the pro-oxidants and antioxidants systems, so that the first is predominant in the organism [17]. This is a common occurrence in drug users [28], excessive exposition to sunlight [29], metabolic alterations originated from obesity [3] or diabetes [30] and even physical exercises [14].…”

“…The oxidative stress is responsible for causing structural damages in the DNA and performs an important role in the development of several diseases, including cancer [30]. The incidence of oxidative stress in the development and progress of more than 100 diseases has been suggested by several scientists.…”

“…However, other potential mechanisms also must be considered: body fat and estrogen production (breast cancer in men and women), body fat and pancreatic inflammation induced by fat (pancreas cancer), visceral fat and hepatic steatosis (liver cancer), metabolic syndrome and resistance to insulin, thus producing mitogenic effect to insulin (all cancers) [30].…”