Ferroptosis promotes anti-tumor immune response by inducing immunogenic exposure in HNSCC.

Accumulated evidence indicates that immune cell populations play pivotal roles in the process of tumor initiation, progression, recurrence, metastasis, and immune escape. Ferroptosis is a form of regulating cell death in the nexus between metabolism, redox biology, and human health. Ferroptosis is considered as a vital important event in HNSCC, but the underling mechanism of regulating immune cell populations remains poorly understood. Our tissue microarray study showed that patients with high expression of GPX4 were related to poor survival. Moreover, the expression of GPX4 has been negatively associated with immunogenic cell death-related protein calreticulin in HNSCC tissue cohort. Further, RSL3 was used to induce ferroptosis in HNSCC xenograft of C3H/He mouse. We found that the occurrence of ferroptosis had significantly reduced the number of myeloid-derived suppressor cells (MDSCs) and tumor-associated M2-like macrophages (M2 TAMs) in tumor microenvironment. Meanwhile, the tumor-infiltrating CD4 and CD8 T cells were increased. And the calreticulin and HMGB1 may be potential candidate proteins improving the immunosuppressive tumor microenvironment. Taken together, our project suggests that ferroptosis can promote anti-tumor immune response by reversing immunosuppressive microenvironment, indicating that ferroptosis inducer is a promising therapeutic strategy in HNSCC.