GLP-1 class drugs, which have taken the world by storm as obesity treatments, are now showing promising potential in the field of oncology. After demonstrating effectiveness in cardiovascular and kidney diseases, recent studies have revealed possibilities for breast cancer prevention and inhibition of cancer progression, sparking interest in how far their applications might extend.
Initially developed to treat type 2 diabetes, GLP-1 receptor agonists like Wegovy (semaglutide) and Mounjaro (tirzepatide) have seen a surge in prescriptions worldwide as obesity treatments.
GLP-1 has been one of the most rapidly expanding drugs in medicine over the past five years. Beyond weight loss, large-scale clinical trials have confirmed its benefits in reducing heart attack and stroke risks, as well as protecting kidney function. It’s now viewed as a medication that manages various metabolic disorders rather than just an obesity treatment.
At the recent American Society of Clinical Oncology Annual Meeting (ASCO 2023) in Chicago, researchers presented studies suggesting GLP-1’s potential anticancer effects.
A standout study came from Dr. Elizabeth McDonald’s team at the University of Pennsylvania’s Perelman School of Medicine. Their analysis of over 111,000 overweight women aged 45 to 80 found that about 15,000 women prescribed GLP-1 drugs had a 35.1% lower risk of developing breast cancer compared to those not prescribed the medication.
The researchers noted that this result held even after adjusting for factors like age, race, body mass index (BMI), and diabetes status. They also observed risk reduction in analyses focusing solely on obese women at high risk for breast cancer.
The team emphasizes that these results may not be due to weight loss alone. They suggest GLP-1 drugs might reduce chronic inflammation and improve metabolic status during weight loss, potentially affecting various cancer growth-related signaling pathways.
Another study indicated GLP-1 could slow cancer progression. Cleveland Clinic researchers analyzed 12,112 patients with obesity-related cancers, including lung, breast, colon, and liver cancers. They found that the risk of distant metastasis or stage IV progression was 38% to 50% lower in the GLP-1 group.
Risk reduction varied by cancer type: 50% for non-small cell lung cancer, 43% for breast cancer, 38% for liver cancer, and 31% for colon cancer. Patients with higher GLP-1 receptor expression in tumors had better survival rates, particularly in breast cancer, where the death risk was 45% lower.
Dr. Lee Jun-yeop, Professor of Endocrinology at Catholic University’s Seoul St. Mary’s Hospital, commented that recent studies show GLP-1 receptor agonists are evolving beyond glucose-lowering agents or obesity treatments to impact various chronic diseases. The medical community now views GLP-1 not just as a weight-loss drug but as a Disease-Modifying Therapy.
He added that obesity is a common risk factor for cardiovascular disease, chronic kidney disease, fatty liver, and certain cancers. GLP-1 drugs could potentially reduce these diseases’ incidence through weight loss, inflammation control, metabolic improvement, and vascular protection. Recent studies have shown promising results in risk reduction and cancer progression inhibition for obesity-related cancers like breast, colon, liver, and lung cancers.
However, experts caution that evidence is still insufficient to use GLP-1 drugs for cancer prevention or treatment. Most current studies are observational, using real clinical data, making it challenging to distinguish between weight loss effects and direct anticancer effects.
Dr. Lee stated that it’s premature to recommend GLP-1 for cancer prevention or treatment without randomized clinical trials establishing causality. Cancer research with GLP-1 is still in early stages and requires further clinical studies.
Indeed, expanding GLP-1 indications hasn’t always succeeded. Dementia was another area of high expectations, but Novo Nordisk’s large clinical trial last November showed semaglutide didn’t significantly slow Alzheimer’s progression, halting its potential as a dementia treatment.
Conversely, substantial evidence has accumulated for cardiovascular and kidney diseases. Large-scale trials have confirmed GLP-1’s effectiveness in reducing heart attack, stroke, and cardiovascular mortality risks, and in slowing kidney function decline in chronic kidney disease patients. Its potential has also expanded to treating metabolic dysfunction-associated steatotic liver disease (MASH).
Dr. Lee noted that cardiovascular, kidney, and metabolic disease fields have strong clinical evidence and are currently most promising. Recent findings show improvements in liver inflammation and fibrosis, positioning GLP-1 as a treatment for systemic diseases arising from obesity.
He concluded that if current observational results are confirmed through clinical trials in oncology, GLP-1 could play a significant role in cancer prevention strategies.
