Sustained high levels of sugars damage our cells and can….
Scientists led by Dr. Custodia Garcia-Jimenez at the University Rey Juan Carlos in Madrid have uncovered a key mechanism that links obesity and diabetes with cancer: high sugar levels, which increase the activity of a gene widely implicated in cancer progression.
Dr. Jimenez studied how cells in the intestine respond to sugars and signal to the pancreas to release insulin, the key hormone that controls blood sugar levels. Sugars in the intestine trigger cells to release a hormone called GIP that enhances insulin release by the pancreas.
In a published study, Dr. Garcia Jimenez’s team showed that the ability of the intestinal cells to secrete GIP is controlled by a protein called β-catenin, and that the activity of β-catenin is strictly dependent on sugar levels.
Increased activity of β-catenin is known to be a major factor in the development of many cancers and can make normal cells immortal, a key step in early stages of cancer progression. The study demonstrates that high (but not normal) sugar levels induce nuclear accumulation of β-catenin and lead to cell proliferation. The β-catenin changes, the molecules involved, and the diversity of cancer cells susceptible to these changes are identified.
Dr. Custodia García said, "We were surprised to realize that changes in our metabolism caused by dietary sugar impact our cancer risk. We are now investigating what other dietary components may influence our cancer risk. Changing diet is one of the easiest prevention strategies that can potentially save a lot of suffering and money."
Colin Goding, Professor of Oncology at the University of Oxford, UK, said, "Previously we were unsure about how increased blood sugar found in diabetes and obesity could increase cancer risk. This study identifies a key molecular mechanism through which high blood glucose would predispose to cancer. It opens the way for potential novel therapies aimed at reducing cancer risk in the obese and diabetic populations."
Estimations published by the World Health Organization: obesity predisposes to diabetes and its prevalence is doubling every 20 years worldwide. More than 1 in 10 adults worldwide (12%) are obese (BMI greater than 30). One in 6 children in the UK and Spain suffer obesity.
More than half (63%) of premature deaths worldwide are due to non-communicable diseases of which cancer and diabetes are among the 4 most frequent causes. At least 1 in 3 of the main cancers (27-39%) can be prevented by improving diet, physical activity and body composition.
Molecular Cell Jan 2013