Identification of ferroptosis-related genes as diagnostic biomarkers and therapeutic targets in sorafenib-resistant HCC via machine learning and experimental validation.

Liver cancer, particularly hepatocellular carcinoma (HCC), remains a significant health burden with poor survival rates due to late diagnosis and limited treatment options. Sorafenib, a multi-kinase inhibitor, is the standard first-line therapy for advanced HCC, but long-term use often leads to drug resistance. Ferroptosis, an iron-dependent form of regulated cell death, has emerged as a crucial target in cancer therapy, showing potential to enhance treatment efficacy and overcome drug resistance. Previous studies have demonstrated that sorafenib triggers ferroptosis in HCC cells and that ferroptosis plays a significant role in the development of sorafenib resistance. However, the intricate interplay between ferroptosis and sorafenib resistance remains poorly understood, hampering the development of effective therapeutic strategies. Our study focuses on the intricate interplay between ferroptosis and sorafenib resistance in HCC. Using the GSE109211 dataset, we identified differentially expressed ferroptosis-related genes associated with sorafenib resistance. Notably, these genes stratified sorafenib-resistant HCC patients into distinct subgroups with different drug sensitivities, immune cell infiltrations, and responses to chemotherapy and immunotherapy. Through machine learning algorithms, three hub genes (ECH1, SLC25A28 and ULK1) were identified to be closely associated with sorafenib resistance. A novel ferroptosis-related signature comprising these genes emerged as a robust diagnostic model, validated by ROC curve analysis, for predicting sorafenib resistance in HCC patients. Furthermore, experimental validation confirmed the upregulation of ECH1, SLC25A28 and ULK1 expressions in sorafenib-resistant HCC cells, with sorafenib treatment altering their expression profiles. Knockdown of ULK1 in sorafenib-resistant HCC cells potently enhanced sorafenib-induced ferroptosis, thereby alleviating sorafenib resistance. Our findings not only identify pivotal ferroptosis-related genes as diagnostic biomarkers for sorafenib resistance but also provide insights into the role of ferroptosis in modulating sorafenib responsiveness. This study offers a promising strategy to overcome sorafenib resistance and improve patient outcomes in HCC treatment, highlighting the potential of ferroptosis-targeted therapies in cancer management.