From Defense to Offense: How Autoimmunity Influences Cancer Progression

Abstract

Autoimmune disorders represent significant global health challenges, characterized by aberrant immune responses against the body’s own tissues, leading to a spectrum of conditions with varying severity. Concurrently, primary immunodeficiencies (PIs) compromise immune tolerance, heightening susceptibility to infections, malignancies, and autoimmune diseases. Notably, there is an emerging recognition of the bidirectional relationship between autoimmunity and cancer, as autoimmune responses may play dual roles: while excessive autoimmunity can promote tissue damage and malignancy, certain immune responses can also exhibit protective effects against tumors. This review meticulously examines the interplay between various immune cells, including T lymphocytes, neutrophils, and macrophages, in both malignancies and autoimmune disorders. It explores how chronic inflammation, driven by autoimmune conditions, can foster an environment conducive to tumor progression, while also considering how immune regulatory mechanisms can become dysfunctional in the face of malignancy. Furthermore, we discuss the implications of recent advancements in cancer immunotherapy which highlight the complexities of using immune checkpoint inhibitors in patients with pre-existing autoimmune conditions. Ultimately, this review posits that a nuanced understanding of the intricate relationships between autoimmunity and cancer could inform novel therapeutic strategies and improve outcomes for affected patients.