Synergistic Potential of GLP-1 Receptor Agonists and Radiotherapy in Breast Cancer Treatment: A New Therapeutic Avenue (TROD-GROG 006)

Introduction: GLP-1 receptor agonists (GLP-1 RA) are drugs used to treat diabetes by enhancing insulin sensitivity and secretion. Recent studies suggest their potential anti-cancer effects, including anti-inflammatory and antioxidant properties. This study evaluates the combined effects of GLP-1 RAs and radiotherapy (RT) on breast cancer progression in a BALB/c mouse model. Materials and Methods: In this study, BALB/c mice were injected with 4T1 breast cancer cells to induce tumors. The mice were randomly assigned to five groups: control, placebo, GLP-1 RA, RT, and combined GLP-1 RA with RT. Histological and immunohistochemical analyses were performed on the tumor tissues to assess changes in morphology and protein expression related to inflammation and apoptosis. In vitro, cell viability assays were also conducted on 4T1 cells to evaluate the effects of GLP-1 RA and RT. Results: The combination of GLP-1 RA and RT resulted in significant tumor size reduction compared to the other treatment groups. Histological analysis showed improved tissue morphology, with restored healthy appearance in tumors treated with both GLP-1 RA and radiotherapy. Immunohistochemical staining revealed changes in the expression of apoptosis-related proteins. In vitro assays demonstrated that the combined treatment significantly decreased the viability of 4T1 breast cancer cells. Conclusion: This study concludes that the GLP-1 RAs and RT combination enhances tumor control and improves histological outcomes in a breast cancer model. This approach offers a promising strategy for patients with coexisting diabetes and breast cancer, potentially improving treatment efficacy and patient outcomes.