NEW DELHI: Could the same high blood sugar that damages the body also make some immune cells better at fighting cancer? New research offers a surprising clue, finding that high blood sugar enhances the tumour-fighting ability of immune cells in mice, potentially opening a new avenue for cancer treatment.Published in The Journal of Immunology, the study examined why people with type 1 diabetes have been found to have a lower risk of certain cancers, including melanoma, breast and colon cancer. Researchers found that the answer may lie in how high blood sugar changes T cells, immune cells that help the body recognise and attack cancer cells.In experiments, tumours grew more slowly in mice with high blood sugar than in mice with normal blood sugar and diabetic mice whose blood sugar was controlled with insulin. The hyperglycaemic mice also had more T cells, which were more effective at controlling tumour growth.The researchers found that high blood sugar altered a cellular signalling pathway in these immune cells, helping enhance their cancer-fighting activity. When diabetic mice received insulin, their T cells lost this heightened ability, pointing to a possible link between blood sugar levels and immune-cell function.The team then looked for similar changes in humans and found increased activity in the same signalling pathway in immune cells from blood samples of people with high blood sugar. This suggests the mechanism observed in mice may also be relevant to humans, although it does not establish that high blood sugar reduces cancer risk in people.
Dr Anamika Bose, assistant professor at the National Institute of Pharmaceutical Education and Research in India and senior author of the study, said the findings could help researchers develop T-cell-based immunotherapies by replicating the immune-cell changes seen in the experiments.The potential lies not in using high blood sugar as a treatment, but in understanding how it changes immune cells and whether those effects can be reproduced safely through targeted therapies.The findings remain preliminary. The tumour experiments were conducted in mice, and further research is needed to determine whether manipulating the same signalling pathway can improve cancer treatment in humans. The study does not suggest that patients should leave diabetes uncontrolled or alter insulin treatment.