Although great progress has been made in exploring new treatments for RA. To date, elucidating the pathogenesis of RA remains a major challenge, thus it is urgent to explore the molecular mechanisms of these diseases. Moreover, several studies have illustrated that ferroptosis may be involved in various tumor types [29, 30]. However, there have been few studies focused specifically on ferroptosis-associated genes in RA.
In our study, there were 34 potential ferroptosis-related genes were identified between RA patients and healthy individuals by using bioinformatic analyses. Furthermore, GO and KEGG enrichment analyses were conducted to investigate the biological functions of the 34 DEFGs. The oxidative stress, oxidoreductase complex, and NADPH oxidase were significantly enriched by these DEFGs, indicating that these DEFGs were associated with oxidation, which was consistent with previous reports [31].
Based on KEGG pathway enrichment, we found that these genes were significantly enriched in FoxO signaling pathway, HIF-1 signaling pathway, and Ferroptosis pathway. Lee et al. [32] identified FoxO3 as a biomarker of RA severity, and its haplotype was associated with erosion scores of RA. Kok et al. [33] reported that SIRT-1/FoxO3a signaling played a crucial role in the occurrence and development of RA. Besides, FoxO signaling was also vital in OA. Abnormal expression of FoxO had been reported to be closely associated with osteoarthritis [34]. HIF-1α is a very important transcription factor that regulates developmental and cellular responses to hypoxia. A deficiency of HIF-1α has been reported to exacerbate MMP13 expression levels to lead to degrading cartilage tissue [35]. Our results represented these RA-related pathways, which might enhance our understanding of RA pathogenesis.
Furthermore, we identified 4 DEFGs (GABARPL1, DUSP1, JUN, and MAPK8) and observed that the expression levels of these genes in the GSE55235 were consistent with the GSE12021 dataset. Several genes had been shown to be closely related to RA. For example, DUSP1 is a phosphatase with dual specificity for tyrosine and threonine, which involves cellular processes by regulating MAPK1/ERK2. Vattakuzhi et al. [36] found that DUSP1 can regulate MAPK signaling and its low expression may be related to osteolytic lesions in arthritis. JUN is the putative transforming gene of avian sarcoma virus 17. It regulated gene expression by interacting with specific target DNA sequences [37]. Huber et al. [38] revealed that Jun/Fos proto-oncogene was significantly decreased at the mRNA level in RA. MAPK8, also known as Jun nuclear kinase (JNK), was a member of the MAP kinase family, which was involved in various cellular processes (proliferation, differentiation, transcription regulation, and development) [39]. Ding et al. [40] reported that abnormal activation of MAPKs in synovial tissues of RA patients promoted pannus formation. Thus, MAPK is considered a promising potential target in the treatment of RA.
However, this study still has some limitations. First, this work utilized a small sample size, which might lead to bias. Second. More in-vivo and in-vitro studies were required to verify the reliability and significance of the results. Finally, it is necessary to understand the hub genes of RA for diagnosis and treatment.
In conclusion, we derived 34 potential ferroptosis-related genes between RA patients and healthy individuals using bioinformatics method. There were four genes (GABARPL1, DUSP1, JUN, and MAPK8) were verified to be differentially expressed and may serve as important diagnostic markers and new potential therapeutic targets for RA through the regulation of ferroptosis. Our study may be benefit to enhance the understanding of RA pathogenesis and potential for clinical use in the future.