AILSA CHANG, HOST:
There's mounting evidence suggesting that GLP-1 drugs also help reduce cancer risk. NPR's Yuki Noguchi reports that several recent studies find a strong correlation, but now the question is - why?
YUKI NOGUCHI, BYLINE: GLP-1 drugs act on hormones influencing the brain and gut, reducing hunger and slowing digestion. They originally treated diabetes, but because they act on powerful metabolic levers, they've proved useful against obesity, heart disease, sleep apnea, potentially addiction and now cancer. GLP-1 drugs' potential use in preventing or controlling cancer was a major theme among the research presented by the American Society of Clinical Oncology at its recent meeting. Dr. Julie Gralow, the group's chief medical officer, notes the data all show strong correlation not causation.
JULIE GRALOW: It ties into a body of knowledge about exercise and healthy lifestyles after a cancer diagnosis.
NOGUCHI: The most prominent GLP-1-related research published in the Journal of Clinical Oncology looked at the medical and prescription records of over 10,000 patients with early-stage cancer. Half started GLP-1s after diagnosis. The others took a different diabetes medicine.
GRALOW: Of the seven style of (ph) tumors they chose to look at, they saw a decreased progression to metastatic disease in 6 out of the 7 cancers, four of which were statistically significant.
NOGUCHI: In other words, drugs significantly appeared to lower risks in breast, colorectal, liver and non-small cell lung cancers. Radiologist Elizabeth McDonald is at University of Pennsylvania and co-authored a different study also published in the society's journal. It matched mammogram images to a prescription database. Through that analysis, McDonald says, women between age 45 and 80 taking GLP-1 drugs were 30% less likely to develop breast cancer. And while cancer risks also decline when weight is lost through diet or bariatric surgery, McDonald says the protective effects with GLP-1s appear greater.
ELIZABETH MCDONALD: The weight loss alone just didn't account for the magnitude of the observed effect.
NOGUCHI: How? McDonald suspects in the process of up- or down-regulating hormones having to do with hunger and digestion, GLP-1s also trigger other hormonal pathways.
MCDONALD: Some of these pathways will lead to weight loss, but other pathways will lead to reduction in inflammation, so they have multiple effects.
NOGUCHI: Chronic inflammation can stimulate tumor growth, and more trials are now starting to look at how GLP-1s might influence that. Oncologist Coral Omene at Rutgers plans to follow 40 breast cancer patients starting Tirzepatide, another GLP-1 drug also called Mounjaro or Zepbound. Omene plans to track changes in DNA cancer markers in the blood and hormone and inflammation activity in fat cells.
CORAL OMENE: And as we're treating them, we are going to trace and see how these cells or the immune cells are behaving (ph).
NOGUCHI: That, she says, will hopefully lead to better understanding as how best to use GLP-1 drugs against cancer. Yuki Noguchi, NPR News. Transcript provided by NPR, Copyright NPR.
NPR transcripts are created on a rush deadline by an NPR contractor. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary. The authoritative record of NPR’s programming is the audio record.
