Clear cell renal cell carcinoma (ccRCC) accounts for the highest number of renal malignancies and 3% of all adult cancers. The incidence of ccRCC is increasing worldwide, and its prognosis is poor. Approximately 30% of the patients are diagnosed at a late stage and are frequently asymptomatic. Cuproptosis is a new type of cell death that is regulated by Cu ions. As cuproptosis is associated with cancer development, we hypothesized that changes in the expression of cuproptosis-related genes (CRGs) are associated with the prognosis of ccRCC, and that CRGs can serve as biomarkers for the diagnosis and prognosis of ccRCC. In the present study, we explored the correlation between CRGs and ccRCC prognosis by analyzing publicly available data. We analyzed the clinical information and RNA-sequencing data in The Cancer Genome Atlas using bioinformatics tools. Dihydrolipoamide S-succinyltransferase (DLST) was identified as a novel gene with predictive and diagnostic potential. CRGs were under-expressed in ccRCC samples, and downregulation ofDLSTwas highly associated with poor prognosis. Cox univariate and multivariate regression analyses revealed thatDLSTcould serve as an independent prognostic factor for ccRCC. Further, functional enrichment analysis indicated that low expression ofDLSTmay affect immune function. Our results strongly indicate thatDLSTplays an important role in ccRCC progression and may serve as an independent diagnostic and prognostic biomarker for ccRCC. Therefore,DLSTis a potential therapeutic target for patients with ccRCC.

The aim of the present study was to assess the prognostic value of circular RNA WW and C2 domain-containing protein 3 (circWWC3) in patients with clear cell renal cell carcinoma (ccRCC). The clinicopathological data were collected for patients with ccRCC treated between January 1, 2012, and February 31, 2014, at The Fourth Hospital of Hebei Medical University Hospital (Shijiazhuang, China). A total of 150 patients who underwent nephrectomy were included in the study. Analysis of stored tissues and long-term follow-up data was performed. Fluorescence in situ hybridization was used to detect the relative circWWC3 expression in fresh-frozen cancerous and adjacent para-cancerous tissue samples from patients with ccRCC. A χ 2 test was used to analyze the association between circWWC3 expression levels and the clinicopathological parameters of the patients. A Cox proportional risk regression model was used to analyze the clinical factors affecting patient prognosis. The survival curve was plotted using the Kaplan-Meier method, and the association between circWWC3 expression levels and patient survival status was tested using the log-rank test. circWWC3 expression in cancerous tissues was higher than that in the adjacent normal tissues. Additionally, circWWC3 expression was significantly associated with T stage (P= 0.005) and pathological grade (P= 0.033). Univariate Cox regression analysis showed that overall survival (OS) was associated with T stage, pathological Fuhrman grade and circWWC3 expression levels (all P<0.05). Multivariate Cox regression analysis also yielded similar results in patients with ccRCC (P<0.05). Moreover, the OS time of patients with high circWWC3 expression was significantly shorter than that of patients with low circWWC3 expression. In conclusion, high circWWC3 expression is an independent risk factor affecting patient prognosis, and is expected to be an important prognostic biomarker and novel therapeutic target for patients with ccRCC.

Background: Bladder cancer (BC) is a malignant tumor that occurs in the bladder wall and often appears in elderly individuals. Renal cancer (RC) arises from the renal tubular epithelium, but its molecular mechanism remains unclear. Methods: We downloaded RC datasets (GSE14762 and GSE53757) and a BC dataset (GSE121711) to screen differentially expressed genes (DEGs). We also performed weighted gene coexpression network analysis (WGCNA). We created a protein-protein interaction (PPI) network and performed functional enrichment analysis, such as gene set enrichment analysis (GSEA). Heatmaps were made for gene expression. Survival analysis and immunoinfiltration analysis were performed. Comparative toxicogenomics database (CTD) analysis was performed to find the relationship between disease and hub genes. Western blotting was performed to verify the role of KIF20A in apoptosis. Results: A total of 764 DEGs were identified. The GSEA showed that the DEGs were mainly enriched in organic acid metabolism, drug metabolism, mitochondria, and metabolism of cysteine and methionine. The PPI network in GSE121711 showed that KIF20A was a hub gene of renal clear cell carcinoma. Where the expression level of KIF20A was higher, the prognosis of patients was worse. CTD analysis showed that KIF20A was associated with inflammation, proliferation, and apoptosis. KIF20A expression in the RC group was upregulated, as shown by western blotting. The core proteins (including pRB Ser 780, CyclinA, E2F1, CCNE1, and CCNE2) in the pRB Ser 780/CyclinA signaling pathway were also upregulated in the RC group. Conclusions: KIF20A might be a novel biomarker for researching renal and bladder cancers.