Genetic variation associated with thyroid autoimmunity shapes the systemic immune response to PD-1 checkpoint blockade

Activation of systemic immune responses using PD-1 checkpoint inhibitors is an essential approach to cancer therapy. Yet, the extent of benefit relative to risk of immune related adverse events (irAE) varies widely among patients. Here, we study endocrine irAE from 7 clinical trials across 6 cancers where atezolizumab (anti-PD-L1) was combined with chemotherapies and compared to standard of care. We show that atezolizumab-induced thyroid dysfunction is associated with longer survival. We construct a polygenic risk score (PRS) for lifetime risk of hypothyroidism using a GWAS from the UK Biobank and apply this PRS to genetic data collected from 2,616 patients of European ancestry from these trials. Patients with high PRS are at increased risk of atezolizumab-induced thyroid dysfunction and lower risk of death in triple negative breast cancer. Our results indicate that genetic variation associated with thyroid autoimmunity interacts with biological pathways driving the systemic immune response to PD-1 blockade. Endocrinopathies, such as thyroid autoimmunity, are common among patients treated with immune checkpoint inhibitors. Here, by using a polygenic risk score (PRS) derived from a hypothyroidism GWAS, the authors show that cancer patients with high PRS are at increased risk of atezolizumab (anti-PD-L1)-induced thyroid dysfunction, a condition associated with systemic response to PD-1 checkpoint blockade and longer overall survival.

Automated summary

The study shows that using a polygenic risk score can predict the risk of cancer patients developing atezolizumab (anti-PD-L1)-induced thyroid dysfunction, which is associated with systemic response to PD-1 checkpoint blockade and longer overall survival.