Abstract
Ionizing radiation (IR) induces ferroptosis in head and neck squamous cell carcinoma (HNSCC). But, it remains unclear whether ferroptosis affects the prognosis of HNSCC patients after receiving radiotherapy. This study aims to develop a ferroptosis signature to predict the radiosensitivity and prognosis of HNSCC. Ferroptosis-related genes, clinical data and RNA expression profiles were obtained from the FerrDb database, The Cancer Genome Atlas and GEO database. Prognostic genes were identified by random survival forest, univariate Cox regression, Kaplan-Meier and ROC analyses. Principal component analysis, multivariate Cox regression, nomogram and DCA analyses were conducted to estimate its predictive ability. Functional enrichment and immune-related analyses were performed to explore potential biological mechanisms and tumor immune microenvironment. The effect of the hub gene on ferroptosis and radiosensitivity was verified using flow cytometry, quantitative real-time PCR and clonogenic survival assay. We constructed a ferroptosis-related signature, including IL6, NCF2, metadherin (MTDH) and CBS. We classified patients into high-risk (HRisk) and low-risk groups according to the risk scores. The risk score was confirmed to be an independent predictor for overall survival (OS). Combining the clinical stage with the risk score, we established a predictive nomogram for OS. Furthermore, pathways related to tumorigenesis and tumor immune suppression were mainly enriched in HRisk. MTDH was verified to have a potent effect on IR-induced ferroptosis and consequently promoted radiosensitivity. We constructed a ferroptosis-related signature to predict radiosensitivity and OS in HNSCC patients. MTDH was identified as a promising therapeutic target in radioresistant HNSCC patients.