A new study by researchers at the University of Texas in Austin finds that recurrence of hormone-related breast cancer was reduced by more than half in overweight and obese women who regularly used nonsteroidal anti-inflammatory drugs.
The researchers examined data from 440 women with invasive, estrogen receptor alpha (ERα)-positive breast cancer who were treated at the University of Texas Health Science Center and the START Center for Cancer Care clinic (both in San Antonio, TX) between 1987 and 2011.
In this group, 58.5% of the women were obese and 25.8% were overweight. Around 81% took aspirin and the rest took another nonsteroidal anti-inflammatory drug (NSAID). About 42% of the women took statins and 25% took omega-3 fatty acid.
Even after controlling for statins and omega-3 fatty acid use, the results demonstrated a protective effect from aspirins and other NSAIDs.
The researchers found that women with a body mass index greater than 30 who had ERα-positive breast cancer had a 52% lower rate of recurrence and a 28-month delay in recurrence if they were taking aspirin or other NSAIDs.
"Our studies suggest that limiting inflammatory signaling may be an effective, less toxic approach to altering the cancer-promoting effects of obesity and improving patient response to hormone therapy," says Linda A. deGraffenried, PhD, associate professor of nutritional sciences at the University of Texas.
"These results suggest that NSAIDs may improve response to hormone therapy, thereby allowing more women to remain on hormone therapy rather than needing to change to chemotherapy and deal with the associated side effects and complications. However, these results are preliminary and patients should never undertake any treatment without consulting with their physician."
Dr. deGraffenried and colleagues used blood from obese patients to recreate a tumor environment containing cancer cells, fat cells and inflammation-promoting immune cells. From the results of experiments conducted using this cancer model, they report that factors associated with obesity initiate a network of signaling within the tumor environment that promotes growth and resistance to treatment.
"These studies show that the greatest benefit from aspirin [and other NSAIDs] will be in those with a disease driven by inflammation, and not just obesity," explains deGraffenried.
NSAIDs and other cancers
In 2013, the journal Nature published a study from a research team led by Indiana University School of Medicine scientists that investigated the benefits of NSAIDs for doctors gathering stem cells to treat patients with blood or bone marrow cancers.
In animal studies, using NSAIDS increased stem cell and progenitor cell counts in circulating blood by four to six times. In combination with proteins called growth factors, the mobilization of these cells was even greater.
A 2010 study suggested that one NSAID, called Sulindac, inhibits tumor growth and initiates cell death by binding to a protein - nuclear receptor RXRα - that can promote tumor growth by stimulating proteins that assist the cancer's survival.