Depleting glucose is a sign of cancer

Cancer needs energy to drive its out-of-control growth. It gets energy in the form of glucose, in fact consuming so much glucose that one method for imaging cancer simply looks for areas of extreme glucose consumption – where there is consumption, there is cancer. But how does cancer get this glucose? A University of Colorado Cancer Center study published in the journal Cancer Cell shows that leukemia undercuts the ability of normal cells to consume glucose, thus leaving more glucose available to feed its own growth.

“Leukemia cells create a diabetic-like condition that reduces glucose going to normal cells, and as a consequence, there is more glucose available for the leukemia cells. Literally, they are stealing glucose from normal cells to drive growth of the tumour,” says Craig Jordan, PhD, investigator at University of Colorado Cancer Center, division chief of the Division of Hematology and the Nancy Carroll Allen Professor of Hematology at the University of Colorado School of Medicine. Like diabetes, cancer’s strategies depend on insulin. Healthy cells need insulin to use glucose. In diabetes, either the pancreas under-produces insulin or tissues cannot not respond to insulin and so cells are left starved for energy while glucose builds up in the blood. The current study shows that leukemia goes about creating similar conditions of glucose buildup in two ways.

First, tumour cells trick fat cells into over-producing a protein called IGFBP1. This protein makes healthy cells less sensitive to insulin, meaning that when IGFBP1 is high, it takes more insulin to use glucose than it does when IGFBP1 is low. Unless the supply of insulin goes up, high IGFBP1 means that the glucose consumption of healthy cells goes down. Cancer has a second strategy that ensures insulin production does not go up to meet the need created by increased IGFBP1. In fact, cancers turn insulin production down. In large part, they do this in the gut.