Targeting Cystine Metabolism in the Lung Cancer Environment Enhances the Efficacy of Immune Checkpoint Inhibition.

ABSTRACT: Immunotherapy with Immune Checkpoint Inhibitors (ICIs) has shown promising therapeutic effects in the treatment of lung cancer, the overall efficacy of PD-1/PD-L1 inhibitors is only 20%-30%. Thus, more effective combination therapies are needed. This study finds that cystine and cysteine levels in tumor tissues of lung cancer patients are significantly higher than adjacent non-tumor tissues. Cystine deficiency polarizes macrophages toward an M1 phenotype, secreting more TNF-α, CXCL9, and CXCL10. However, using a cystine-free diet marginally reduces the development of lung cancer in vivo. A cystine-free diet slightly reduces lung cancer progression in vivo. Further studies show that cystine deprivation or erastin-mediated transport inhibition increased PD-L1 expression in macrophages both i

SUBMITTER: Xu Y 

PROVIDER: S-EPMC12463131 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature