Identification And Validation Of Ferroptosis-associated Gene Signature Forsteroid-induced Femoral Head Necrosis

Objective Steroid-induced osteonecrosis of the femoral head(SONFH)is a common orthopedic disease in middle-aged and older adults.However,early diagnostic indicators still need to be improved,resulting in poor treatment outcomes for this disease.In recent years,targeted gene intervention has been considered a promising therapeutic approach but has not yielded outstanding results.The etiology of SONFH is currently unknown,but recent studies suggest that ferroptosis may play a role in its development.Ferroptosis is a novel form of cell death characterized by abnormal accumulation of intracellular iron ions leading to lipid peroxidation,causing cell death.This study aimed to construct a ferroptosis-related gene signature in SONFH by bioinformatics and explore the association between SONFH and ferroptosis to provide new ideas for early diagnosis and treatment of this disease.Methods Peripheral blood gene expression profile data of SONFH patients were collected using the GEO database,and ferroptosis-related genes were screened from the Gene Cards and Ferrdb databases.A prognostic model was constructed using the random forest and LASSO algorithms.The SONFH patient group was divided into high-and low-risk groups according to risk scores,and functional enrichment analysis was performed for the high-risk patient group.In addition,by clustering the immune features of SONFH samples,patient samples were divided into two immune subgroups,correlations between ferroptosis genes and different immune clusters were calculated,and immune infiltration was analyzed using CIBERSORT.Finally,in the in vitro experiments,a SONFH cell model was constructed using dexamethasone in the mouse osteoblast cell lines MC3T3-E1.The CCK-8 assay was used to detect cell viability to select the optimal induction concentration for dexamethasone modeling.The cells were divided into control,drug and experimental groups,and the expression of genes central to the model was verified by real-time quantitative PCR(q RT-PCR).Results A prognostic model of four ferroptosis genes(TXNIP,CISD2,GCLC and SETD1B)was obtained.In addition,99 significantly differentially expressed iron death-related genes were identified,mainly enriched in the cell cycle,meiosis and P53 signaling pathways.Immuno-correlation analysis revealed that TXNIP and SETD1 B were significantly more expressed in immune subpopulation 2 and positively correlated with the expression of different immune cells,such as neutrophils and T helper cells.Immune infiltration analysis of patients in the SONFH high-risk group showed increased levels of CD4+ T cells and natural killer cells and decreased levels of macrophages and plasma cells.Finally,q RT-PCR results showed that the m RNA expression of TXNIP and CISD2 was consistent with the predicted trend.Conclusion A new ferroptosis gene model was constructed and validated that can be used to improve the prognostic performance of SONFH and to determine the potential relationship between the immune microenvironment and ferroptosis genes in this disease.This model can predict the risk of SONFH more accurately,which provides a new idea for the early diagnosis and treatment of SONFH.However,further studies are needed to validate and better understand this disease’s pathogenesis and treatment strategies.