Nuclear receptor co-activator 4 (NCOA4) acts as a selective cargo receptor that binds to ferritin, a cytoplasmic iron storage complex. By mediating ferritinophagy, NCOA4 regulates iron metabolism and releases free iron in the body, thus playing a crucial role in a variety of biological processes, including growth, development, and metabolism. Recent studies have shown that NCOA4-mediated ferritinophagy is closely associated with the occurrence and development of iron metabolism-related diseases, such as liver fibrosis, renal cell carcinoma, and neurodegenerative diseases. In addition, a number of clinical drugs have been identified to modulate NCOA4-mediated ferritinophagy, significantly affecting disease progression and treatment efficacy. This paper aims to review the current research progress on the role of NCOA4-mediated ferritinophagy in related diseases, in order to provide new ideas for targeted clinical therapy.
Humans ; Nuclear Receptor Coactivators/physiology* ; Ferritins/metabolism* ; Animals ; Neurodegenerative Diseases/metabolism* ; Iron/metabolism* ; Autophagy/physiology* ; Liver Cirrhosis/metabolism* ; Carcinoma, Renal Cell/metabolism* ; Kidney Neoplasms/physiopathology*

OBJECTIVES: To analyze the association of CHMP2B expression level of with clinicopathological characteristics and prognosis of clear cell renal cell carcinoma (CRCC) and the possible role of CHMP2B in tumorigenesis and progression of CRCC. METHODS: RNAseq data of CRCC were downloaded from the TCGA database for analysis of CHMP2B expression levels in tumor and adjacent tissues and their correlation with clinicopathological characteristics of the patients. Survival outcomes of the patients with high and low CHMP2B expressions were analyzed using the Kaplan-Meier model, and the COX risk regression model was used for identifying the prognostic factors of the patients. The correlation between CHMP2B expression and immune infiltration, its co-expressed genes, and the effect of CHMP2B gene mutations on immunotherapy responses, and its immunohistochemical expression in CRCC and normal tissues were analyzed. Clinical samples of CRCC were collected to examine CHMP2B expressions using RT-PCR, and cell experiment was carried out to test the effect of CHMP2B overexpression on biological behaviors of CRCC cells. RESULTS: CHMP2B was significantly under-expressed in renal cancer tissues, and its overexpression obviously inhibited the proliferation of CRCC cells in vitro. CHMP2B expression level was significantly correlated with age, gender, lymph node metastasis, and tumor stage, and the patients with low CHMP2B expression had poor survival outcomes. Enrichment and co-expression gene analyses suggested that CHMP2B was mainly involved in viral outgrowth, necrotic apoptosis, endocytosis, and immune-regulatory processes in kidney cancer. CONCLUSIONS CHMP2B is lowly expressed in renal cancer tissues to affect tumor progression and tumor immune processes, and may serve as a prognostic biomarker and therapeutic target for CRCC.
Humans ; Carcinoma, Renal Cell/metabolism* ; Kidney Neoplasms/metabolism* ; Cell Proliferation ; Prognosis ; Cell Line, Tumor ; Male ; Female ; Gene Expression Regulation, Neoplastic

OBJECTIVES: To identify potential molecular targets of quercetin in the treatment of clear cell renal carcinoma (ccRCC). METHODS: The therapeutic targets of quercetin were screened from multiple databases by network pharmacology analysis, and the targets significantly correlated with ccRCC were screened from 4907 plasma proteins using a Mendelian randomization method. The drug-disease network model was constructed to screen the potential key targets. The functions of these targets were evaluated via bioinformatics analysis, and the screened targets were verified in cultured ccRCC cells. RESULTS: Network pharmacology analysis combined with Mendelian randomization identified TP53 (OR=3.325, 95% CI: 1.805-6.124, P=0.0001), ARF4 (OR=0.173, 95% CI: 0.065-0.456, P=0.0003), and DPP4 (OR=0.463, 95% CI: 0.302-0.711, P=0.0004) as the core targets in quercetin treatment of ccRCC. Bioinformatics analysis showed that TP53 was highly expressed in ccRCC, and patients with high TP53 expressions had worse survival outcomes. Molecular docking studies showed that the binding energy between quercetin and TP53 was -5.83 kcal/mol. In cultured 786-O cells, CCK-8 assay and wound healing assay showed that treatment with quercetin significantly inhibited cell proliferation and migration. Quercetin treatment also strongly suppressed the expression of TP53 at both the mRNA and protein levels in 786-O cells as shown by RT-qPCR and Western blotting. CONCLUSIONS TP53 may be the key target of quercetin in the treatment of ccRCC, which sheds light on potential molecular mechanism that mediate the therapeutic effect of quercetin.
Humans ; Quercetin/pharmacology* ; Carcinoma, Renal Cell/genetics* ; Cell Proliferation/drug effects* ; Kidney Neoplasms/genetics* ; Cell Movement/drug effects* ; Tumor Suppressor Protein p53/metabolism* ; Cell Line, Tumor ; Computational Biology

OBJECTIVES: Clear cell renal cell carcinoma (ccRCC) is the most common subtype of renal cell carcinoma (RCC), and developing personalized treatment strategies is crucial for improving patient prognosis. This study aims to develop and validate a preoperative computer tomography (CT) radiomics-based predictive model to estimate Ki-67 expression in ccRCC patients, thereby assisting in clinical treatment decisions and prognosis prediction. METHODS: A retrospective analysis was conducted on 214 ccRCC patients who underwent surgical treatment at Gansu Provincial Hospital between January 2018 and November 2023. Patients were classified into high Ki-67 expression (n=123) and low Ki-67 expression (n=91) groups based on postoperative immunohistochemical staining results. The dataset was randomly divided in a 7꞉3 ratio into a training set (n=149) and a validation set (n=65). Preoperative contrast-enhanced urinary CT images and clinical data were collected. After preprocessing, 5 mm arterial-phase CT images were manually segmented layer by layer to delineate the region of interest (ROI) using ITK-SNAP 3.8 software. Radiomic features were then extracted using the FeAture Explorer (FAE) package. Dimensionality reduction and feature selection were performed using the least absolute shrinkage and selection operator (LASSO) algorithm, yielding the optimal feature set. Three classification models were constructed using logistic regression (LR), multilayer perceptron (MLP), and support vector machine (SVM). The receiver operating characteristic (ROC) curve, area under the curve (AUC), decision curve analysis (DCA), and calibration curves were used for model evaluation. RESULTS: A total of 107 radiomic features were extracted from 5 mm arterial-phase CT images, and twenty-one features significantly associated with Ki-67 expression were selected using the LASSO algorithm. Predictive models were developed using LR, MLP, and SVM classifiers. In the training and validation sets, the AUC values for each model were 0.904 (95% CI 0.852 to 0.956) and 0.818 (95% CI 0.710 to 0.926) for the LR model, 0.859 (95% CI 0.794 to 0.923) and 0.823 (95% CI 0.716 to 0.929) for the MLP model, and 0.917 (95% CI 0.865 to 0.969) and 0.857 (95% CI 0.760 to 0.953) for the SVM model. DCA demonstrated that all models had good clinical net benefit, while calibration curves indicated high accuracy of the predictions, supporting the robustness and reliability of the models. CONCLUSIONS A CT radiomics-based model for predicting Ki-67 expression in ccRCC was successfully developed. This model provides valuable guidance for treatment planning and prognostic assessment in ccRCC patients.
Humans ; Carcinoma, Renal Cell/surgery* ; Kidney Neoplasms/surgery* ; Tomography, X-Ray Computed/methods* ; Ki-67 Antigen/metabolism* ; Retrospective Studies ; Female ; Male ; Middle Aged ; Aged ; Prognosis ; Adult ; Preoperative Period ; Radiomics

OBJECTIVES: To investigate the role of Holliday cross-recognition protein (HJURP) in tumorigenesis, progression, and immunotherapy responses. METHODS: Bioinformatics approaches were used to analyze the expression level of HJURP in various cancers and its association with prognosis, clinical stage, and immune cell infiltration using TCGA, GTEx, SangerBox and TIMER 2.0 databases. LinkedOmics database was employed to investigate HJURP-related genes and their potential functions in kidney renal clear cell carcinoma (KIRC). The expression of HJURP in KIRC samples was examined with immunohistochemistry, Western blotting and qRT-PCR, and the effect of HJURP silencing on cell proliferation and migration was tested in cultured KIRC cells. RESULTS: HJURP was highly expressed in 26 cancers with negative correlations with the patients' survival outcomes in 5 cancers including KIRC (P<0.05). HJURP expression levels was strongly correlated with clinical stages and immune cell infiltration in the tumors. In KIRC, HJURP expression was significantly elevated (P<0.0001) and showed a positive correlation with TNM stage (P<0.05), overall stage (P<0.01) and immune cell infiltration. Gene Ontology (GO) functional analysis showed that HJURP is predominantly enriched in biological processes such as biological regulation and metabolic processes. Concerning cellular components, HJURP is primarily localized to the cell membrane and nucleus. In terms of molecular functions, it is chiefly enriched in activities related to protein binding and ion binding. HJURP was highly expressed in both clinical KIRC tissues and KIRC cell lines (P<0.001). In cultured KIRC cells, silencing of HJURP significantly inhibited cell proliferation and migration abilities. CONCLUSIONS HJURP may serves as an indicator of prognosis and immunotherapy response of KIRC, and its high expression enhances malignant behaviors of KIRC cells.
Humans ; Prognosis ; Kidney Neoplasms/pathology* ; Biomarkers, Tumor/metabolism* ; Carcinoma, Renal Cell/pathology* ; DNA-Binding Proteins/genetics* ; Cell Proliferation ; Cell Line, Tumor ; Cell Movement

Objective: To investigate the expression of glycoprotein non metastatic melanoma protein B (GPNMB) in renal eosinophilic tumors and to compare the value of GPNMB with CK20, CK7 and CD117 in the differential diagnosis of renal eosinophilic tumors. Methods: Traditional renal tumor eosinophil subtypes, including 22 cases of renal clear cell carcinoma eosinophil subtype (e-ccRCC), 19 cases of renal papillary cell carcinoma eosinophil subtype (e-papRCC), 17 cases of renal chromophobe cell carcinoma eosinophil subtype (e-chRCC), 12 cases of renal oncocytoma (RO) and emerging renal tumor types with eosinophil characteristics [3 cases of eosinophilic solid cystic renal cell carcinoma (ESC RCC), 3 cases of renal low-grade eosinophil tumor (LOT), 4 cases of fumarate hydratase-deficient renal cell carcinoma (FH-dRCC) and 5 cases of renal epithelioid angiomyolipoma (E-AML)], were collected at the Affiliated Drum Tower Hospital of Nanjing University Medical School from January 2017 to March 2022. The expression of GPNMB, CK20, CK7 and CD117 was detected by immunohistochemistry and statistically analyzed. Results: GPNMB was expressed in all emerging renal tumor types with eosinophil characteristics (ESC RCC, LOT, FH-dRCC) and E-AML, while the expression rates in traditional renal eosinophil subtypes e-papRCC, e-chRCC, e-ccRCC and RO were very low or zero (1/19, 1/17, 0/22 and 0/12, respectively); the expression rate of CK7 in LOT (3/3), e-chRCC (15/17), e-ccRCC (4/22), e-papRCC (2/19), ESC RCC (0/3), RO (4/12), E-AML(1/5), and FH-dRCC (2/4) variedly; the expression of CK20 was different in ESC RCC (3/3), LOT(3/3), e-chRCC(1/17), RO(9/12), e-papRCC(4/19), FH-dRCC(1/4), e-ccRCC(0/22) and E-AML(0/5), and so did that of CD117 in e-ccRCC(2/22), e-papRCC(1/19), e-chRCC(16/17), RO(10/12), ESC RCC(0/3), LOT(1/3), E-AML(2/5) and FH-dRCC(1/4). GPNMB had 100% sensitivity and 97.1% specificity in distinguishing E-AML and emerging renal tumor types (such as ESC RCC, LOT, FH-dRCC) from traditional renal tumor types (such as e-ccRCC, e-papRCC, e-chRCC, RO),respectively. Compared with CK7, CK20 and CD117 antibodies, GPNMB was more effective in the differential diagnosis (P<0.05). Conclusion: As a new renal tumor marker, GPNMB can effectively distinguish E-AML and emerging renal tumor types with eosinophil characteristics such as ESC RCC, LOT, FH-dRCC from traditional renal tumor eosinophil subtypes such as e-ccRCC, e-papRCC, e-chRCC and RO, which is helpful for the differential diagnosis of renal eosinophilic tumors.
Humans ; Kidney Neoplasms/pathology* ; Carcinoma, Renal Cell/pathology* ; Diagnosis, Differential ; Angiomyolipoma/diagnosis* ; Biomarkers, Tumor/metabolism* ; Leukemia, Myeloid, Acute/diagnosis* ; Membrane Glycoproteins

OBJECTIVE: To identify and characterize read-through RNAs and read-through circular RNAs (rt-circ-HS) derived from transcriptional read-through hypoxia inducible factor 1α (HIF1α) and small nuclear RNA activating complex polypeptide 1 (SNAPC1) the two adjacent genes located on chromosome 14q23, in renal carcinoma cells and renal carcinoma tissues, and to study the effects of rt-circ-HS on biological behavior of renal carcinoma cells and on regulation of HIF1α. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) and Sanger sequencing were used to examine expression of read-through RNAs HIF1α-SNAPC1 and rt-circ-HS in different tumor cells. Tissue microarrays of 437 different types of renal cell carcinoma (RCC) were constructed, and chromogenic in situ hybridization (ISH) was used to investigate expression of rt-circ-HS in different RCC types. Small interference RNA (siRNA) and artificial overexpression plasmids were designed to examine the effects of rt-circ-HS on 786-O and A498 renal carcinoma cell proliferation, migration and invasiveness by cell counting kit 8 (CCK8), EdU incorporation and Transwell cell migration and invasion assays. RT-PCR and Western blot were used to exa-mine expression of HIF1α and SNAPC1 RNA and proteins after interference of rt-circ-HS with siRNA, respectively. The binding of rt-circ-HS with microRNA 539 (miR-539), and miR-539 with HIF1α 3' untranslated region (3' UTR), and the effects of these interactions were investigated by dual luciferase reporter gene assays. RESULTS: We discovered a novel 1 144 nt rt-circ-HS, which was derived from read-through RNA HIF1α-SNAPC1 and consisted of HIF1α exon 2-6 and SNAPC1 exon 2-4. Expression of rt-circ-HS was significantly upregulated in 786-O renal carcinoma cells. ISH showed that the overall positive expression rate of rt-circ-HS in RCC tissue samples was 67.5% (295/437), and the expression was different in different types of RCCs. Mechanistically, rt-circ-HS promoted renal carcinoma cell proliferation, migration and invasiveness by functioning as a competitive endogenous inhibitor of miR-539, which we found to be a potent post-transcriptional suppressor of HIF1α, thus promoting expression of HIF1α. CONCLUSION The novel rt-circ-HS is highly expressed in different types of RCCs and acts as a competitive endogenous inhibitor of miR-539 to promote expression of its parental gene HIF1α and thus the proliferation, migration and invasion of renal cancer cells.
Humans ; Carcinoma, Renal Cell/pathology* ; Cell Proliferation ; Hypoxia ; Kidney Neoplasms ; MicroRNAs/genetics* ; Neoplasm Invasiveness/genetics* ; RNA, Circular/metabolism* ; RNA, Small Interfering ; Hypoxia-Inducible Factor 1, alpha Subunit/genetics*

OBJECTIVE: To explore the effect of curcumin on the proliferation of renal cell carcinoma and analyze its regulation mechanism. METHODS: In RCC cell lines of A498 and 786-O, the effects of curcumin (2.5, 5, 10 µ mo/L) on the proliferation were analyzed by Annexin V+PI staining. Besides, A498 was inoculated into nude mice to establish tumorigenic models, and the model mice were treated with different concentrations of curcumin (100, 200, and 400 mg/kg), once daily for 30 days. Then the tumor diameter was measured, the tumor cells were observed by hematoxylin-eosin staining, and the protein expressions of miR-148 and ADAMTS18 were detected by immunohistochemistry. In vitro, after transfection of miR-148 mimics, miR-148 inhibitor or si-ADAMTS18 in cell lines, the expression of ADAMTS18 was examined by Western blotting and the cell survival rate was analyzed using MTT. Subsequently, Western blot analysis was again used to examine the autophagy phenomenon by measuring the relative expression level of LC3-II/LC3-I; autophagy-associated genes, including those of Beclin-1 and ATG5, were also examined when miR-148 was silenced in both cell lines with curcumin treatment. RESULTS: Curcumin could inhibit the proliferation of RCC in cell lines and nude mice. The expression of miR-148 and ADAMTS18 was upregulated after curcumin treatment both in vitro and in vivo (P<0.05). The cell survival rate was dramatically declined upon miR-148 or ADAMTS18 upregulated. However, si-ADAMTS18 treatment or miR-148 inhibitor reversed these results, that is, both of them promoted the cell survival rate. CONCLUSION Curcumin can inhibit the proliferation of renal cell carcinoma by regulating the miR-148/ ADAMTS18 axis through the suppression of autophagy in vitro and in vivo. There may exist a positive feedback loop between miR-148 and ADAMTS18 gene in RCC.
Animals ; Mice ; Carcinoma, Renal Cell/metabolism* ; Curcumin/therapeutic use* ; MicroRNAs/metabolism* ; Mice, Nude ; Cell Line, Tumor ; Kidney Neoplasms/metabolism* ; Autophagy ; Cell Proliferation ; Gene Expression Regulation, Neoplastic ; ADAMTS Proteins/metabolism*

OBJECTIVE: To explore the potential mechanism of resistance to axitinib in clear cell renal cell carcinoma (ccRCC), with a view to expanding the understanding of axitinib resistance, facilitating the design of more specific treatment options, and improving the treatment effectiveness and survival prognosis of patients. METHODS: By exploring the half maximum inhibitory concentration (IC₅₀) of axitinib on ccRCC cell lines 786-O and Caki-1, cell lines resistant to axitinib were constructed by repeatedly stimulated with axitinib at this concentration for 30 cycles in vitro. Cell lines that were not treated by axitinib were sensitive cell lines. The phenotypic differences of cell proliferation and apoptosis levels between drug resistant and sensitive lines were tested. Genes that might be involved in the drug resistance process were screened from the differentially expressed genes that were co-upregulated in the two drug resistant lines by transcriptome sequencing. The expression level of the target gene in the drug resistant lines was verified by real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot (WB). The expression differences of the target gene in ccRCC tumor tissues and adjacent tissues were analyzed in the Gene Expression Profiling Interactive Analysis (GEPIA) public database, and the impact of the target gene on the prognosis of ccRCC patients was analyzed in the Kaplan-Meier Plotter (K-M Plotter) database. After knocking down the target gene in the drug resistant lines using RNA interference by lentivirus vector, the phenotypic differences of the cell lines were tested again. WB was used to detect the levels of apoptosis-related proteins in the different treated cell lines to find molecular pathways that might lead to drug resistance. RESULTS: Cell lines 786-O-R and Caki-1-R resistant to axitinib were successfully constructed in vitro, and their IC₅₀ were significantly higher than those of the sensitive cell lines (10.99 μmol/L, P < 0.01; 11.96 μmol/L, P < 0.01, respectively). Cell counting kit-8 (CCK-8) assay, colony formation, and 5-ethynyl-2 '-deoxyuridine (EdU) assay showed that compared with the sensitive lines, the proliferative ability of the resistant lines decreased, but apoptosis staining showed a significant decrease in the level of cell apoptosis of the resistant lines (P < 0.01). Although resistant to axitinib, the resistant lines had no obvious new replicated cells in the environment of 20 μmol/L axitinib. Nuclear protein 1 (NUPR1) gene was screened by transcriptome sequencing, and its RNA (P < 0.0001) and protein expression levels significantly increased in the resistant lines. Database analysis showed that NUPR1 was significantly overexpressed in ccRCC tumor tissue (P < 0.05); the ccRCC patients with higher expression ofNUPR1had a worse survival prognosis (P < 0.001). Apoptosis staining results showed that knockdown ofNUPR1inhibited the anti-apoptotic ability of the resistant lines to axitinib (786-O, P < 0.01; Caki-1, P < 0.05). WB results showed that knocking downNUPR1decreased the protein level of B-cell lymphoma-2 (BCL2), increased the protein level of BCL2-associated X protein (BAX), decreased the protein level of pro-caspase3, and increased the level of cleaved-caspase3 in the resistant lines after being treated with axitinib. CONCLUSION ccRCC cell lines reduce apoptosis through theNUPR1 -BAX/ BCL2 -caspase3 pathway, which is involved in the process of resistance to axitinib.
Humans ; Carcinoma, Renal Cell/metabolism* ; Axitinib/pharmacology* ; Kidney Neoplasms/metabolism* ; bcl-2-Associated X Protein ; Nuclear Proteins ; Cell Line, Tumor ; Apoptosis ; Cell Proliferation

Aldolase B (ALDOB), a glycolytic enzyme, is uniformly depleted in clear cell renal cell carcinoma (ccRCC) tissues. We previously showed that ALDOB inhibited proliferation through a mechanism independent of its enzymatic activity in ccRCC, but the mechanism was not unequivocally identified. We showed that the corepressor C-terminal-binding protein 2 (CtBP2) is a novel ALDOB-interacting protein in ccRCC. The CtBP2-to-ALDOB expression ratio in clinical samples was correlated with the expression of CtBP2 target genes and was associated with shorter survival. ALDOB inhibited CtBP2-mediated repression of multiple cell cycle inhibitor, proapoptotic, and epithelial marker genes. Furthermore, ALDOB overexpression decreased the proliferation and migration of ccRCC cells in an ALDOB-CtBP2 interaction-dependent manner. Mechanistically, our findings showed that ALDOB recruited acireductone dioxygenase 1, which catalyzes the synthesis of an endogenous inhibitor of CtBP2, 4-methylthio 2-oxobutyric acid. ALDOB functions as a scaffold to bring acireductone dioxygenase and CtBP2 in close proximity to potentiate acireductone dioxygenase-mediated inhibition of CtBP2, and this scaffolding effect was independent of ALDOB enzymatic activity. Moreover, increased ALDOB expression inhibited tumor growth in a xenograft model and decreased lung metastasis in vivo. Our findings reveal that ALDOB is a negative regulator of CtBP2 and inhibits tumor growth and metastasis in ccRCC.
Humans ; Carcinoma, Renal Cell/genetics* ; Fructose-Bisphosphate Aldolase/metabolism* ; Co-Repressor Proteins/metabolism* ; Transcription Factors/genetics* ; Kidney Neoplasms/genetics* ; Cell Line, Tumor ; Cell Proliferation/genetics* ; Gene Expression Regulation, Neoplastic