Childhood leukaemia has been linked to obesity in new research by doctors at the Children’s Hospital Los Angeles, USA.
Dr Steven Mittelman and colleagues believe that obesity is "an important factor contributing to chemotherapy resistance and increasing relapse rates among children with leukaemia".
In a report in the journal Cancer Research, they explain that obesity is linked with a 50 per cent higher chance of relapsing after treatment for leukaemia. Dr Mittelman says this could be due to a variety of factors.
"It may impair the immune system’s ability to stop cancer, or predispose cells to become cancerous," he said. "Once you have cancer, and if you are obese, the fat cells themselves may impair the ability of chemotherapy to fight cancerous cells," he added.
The team used cells from mice to investigate the increased risk of relapse. Leukaemia cells were mixed with fat cells and given the traditional chemotherapy drugs used in children – vincristine, nilotinib, daunorubicin and dexamethasone.
Results showed that the drugs all worked less effectively when fat cells were nearby. Dr Mittelman says that when the mice relapsed, his team found leukaemia "hiding out" in the fat tissue during chemotherapy.
"These four drugs attack leukaemia cells by different routes, so when we saw fat cells blocking them we realised there could be an important mechanism promoting their ability to live and divide," he said. "We were surprised to find leukaemia cells in the fat tissue."
Dr David Hockenbery of the Fred Hutchinson Cancer Research Center, Seattle, Washington, USA, commented: "This study provides striking experimental support for the clinical observations that obesity is associated with poor prognosis in multiple cancers."
Leave a Reply