Reid Gregor
New research from the Faculty of Medicine and BC Children’s Hospital provides insight into how infections early in life may reduce the risk of leukemia, the most common type of childhood cancer.
“We have known about a link between early-life infection and reduced risk of children getting acute lymphoblastic leukemia for quite a long time,” says Assistant Professor of Pediatrics Gregor Reid, the lead author of the paper, published in the October 2016 issue of Leukemia. “This study provides the first description of immune mechanisms underlying this association.”
Acute lymphoblastic leukemia (ALL) is caused when abnormal white blood cells are transformed into leukemia cells. In a common form of ALL, the abnormal cells, called B-cell precursors (BCPs), are often produced before birth. In these cases, children have a prolonged pre-leukemic phase, the period before leukemia develops.
Dr. Reid, an Investigator with the Michael Cuccione Childhood Cancer Research Program at BC Children’s Hospital, an agency of the Provincial Health Services Authority, found that when the immune system is exposed to infections during the pre-leukemic phase, the activated immune response may reduce the risk of leukemia developing. The receptors that recognize infections and initiate the immune response trigger the production of interferons, which attack both the infection and the abnormal BCP cells, reducing their ability to turn into cancer.
This new research, using a mouse model, could highlight potential targets for future treatment options and preventative measures that could slow down or stop the progression of leukemia.
“A better understanding of the immune responses that target the abnormal cells in ALL will enable us to develop more effective ways to harness these activities to stop leukemia returning in children who have undergone treatment,” Dr. Reid says.
Dr. Reid and his research team are now looking more closely at why early-life infections seem to be better at targeting abnormal BCP cells than those that occur in older children.
In B.C., 30 per cent of childhood cancer patients are diagnosed with leukemia, with ALL being the most common form of the disease. ALL is treatable in over 90 per cent of cases in Canada; however, current treatments are unable to help all patients, and an average of 119 children die each year when their leukemia comes back after treatment.
Leukemia survivors experience life-long complications as a result of cancer and treatment, including neurocognitive impairments, organ dysfunction, and potentially the development of other cancers. In all cases, children with leukemia and their families go through continuous physical, emotional and financial stress and often require additional support over the long term.