Tirzepatide restricts obesity-related tumor growth by reversing metabolic dysregulation and rescuing CD8+ T cell function

Abstract

Obesity, an established risk and progression factor for at least 13 cancer types, is highly prevalent globally, and effective strategies to mitigate the burden of obesity-related cancer are urgently needed. We investigated whether tirzepatide, a widely used incretin-mimetic drug that induces substantial weight loss, offers anticancer benefits. Across 3 tumor models, we demonstrate that chronic tirzepatide treatment reverses diet-induced increases in body weight and fat mass, systemic metabolic perturbations, and tumor growth. We also showed that the anticancer activity of tirzepatide does not involve direct effects on the neoplastic cells used, which lack incretin receptor expression. The anticancer actions of tirzepatide require the reversal of both the metabolic dysregulation and hyporesponsiveness of CD8+ tumor infiltrating lymphocytes evident in obesity. Our findings establish tirzepatide as a promising compound for intercepting obesity-related cancers.