Kidney Renal Clear Cell Carcinoma Tissues Research Articles

SLC11A1 promotes kidney renal clear cell carcinoma (KIRC) progression by remodeling the tumor microenvironment

Kidney renal clear cell carcinoma (KIRC) is a highly immune-infiltrated kidney cancer with the highest mortality rate and the greatest potential for invasion and metastasis. Solute carrier family 11 member1 (SLC11A1) is a phagosomal membrane protein located in monocytes and plays a role in innate immunity, autoimmune diseases, and infection, but its expression and biological role in KIRC is still unknown. In this study, we sought to investigate the potential value of SLC11A1 according to tumor growth and immune response in KIRC. TIMER and UALCAN database was used to analyze the expression feature and prognostic significance of SLC11A1 and its correlation with immune-related biomarkers in KIRC. Proliferation, migration, and invasion were measured using colony formation, EdU, and transwell assays. Role of SLC11A1 on KIRC tumor growth was examined by the xenograft tumor model in vivo. Effects of KIRC cells on macrophage polarization and the proliferation and apoptosis of CD8+ T cells were analyzed using flow cytometry assays. Herein, SLC11A1 was highly expressed in KIRC tissues and cell lines. SLC11A1 downregulation repressed KIRC cell proliferation, migration, invasion, macrophage, and lymphocyte immunity in vitro, as well as hindered tumor growth in vivo. SLC11A1 is significantly correlated with immune cell infiltration and immune-related biomarkers. In KIRC patients, SLC11A1 is highly expressed and positively correlated with the immune-related factors CCL2 and PD-L1. SLC11A1 induced CCL2 and PD-L1 expression, thereby activating the JAK/STAT3 pathway. SLC11A1 deficiency constrained KIRC cell malignant phenotypes and immune response via regulating CCL2 and PD-L1-mediated JAK/STAT3 pathway, providing a promising therapeutic target for KIRC treatment.

Correlation between methylation of interferon regulatory factor 6 gene promoter in renal tissues and overall survival of patients with Kidney renal clear cell carcinoma

To assess the prognostic value of methylation of interferon regulatory factor 6 (IRF6) gene promoter in patients diagnosed with Kidney renal clear cell carcinoma (KIRC). The primary lesions of fifty KIRC patients who were diagnosed at the First Affiliated Hospital of Nanjing Medical University from January 2016 to January 2020 were collected. The expression of IRF6 protein was determined with an immunohistochemical method. The correlation between the level of IRF6 expression and survival and/or metastasis status was analyzed. The mRNA and protein levels of the IRF6 in KIRC and normal renal tissues were compared by using bioinformatic tools. The difference in the methylation rate of the IRF6 gene promoter between tumor and adjacent tissues was analyzed by searching the online databases. Statistical analysis was carried out for the methylation status of the IRF6 gene promoter region to select those negatively correlated with the overall survival (OS) among the patients. In vitro experiments were conducted with cell lines to verify the correlation between the status of promoter methylation and transcription level of the IRF6 gene. The mRNA and protein levels of the IRF6 gene in KIRC tissues were significantly lower than those of the normal controls, and this was more prominent in patients who had died or developed metastasis. The extent of IRF6 gene promoter methylation in the KIRC tissues was much higher compared with that of the adjacent normal renal tissues. There was a significant negative correlation between the methylation of the IRF6 gene promoter and mRNA level of the IRF6 (R = -0.52). The higher methylation degree in the IRF6 gene promoter regions cg12034118 and cg16030177, the shorter the OS and worse prognosis in the patients. Only twenty CpG sites in cg12034118 were confirmed to be highly methylated in KIRC cell lines. The transcription level of the IRF6 gene was upregulated in a time- and dose-dependent manner after the treatment with demethylation reagent 5-azadeoxycytidine. The methylation of IRF6 gene promoter in the renal tissues of KIRC patients is closely correlated with the OS. Cg12034118 may provide a promising biomarker for laboratory detection, and its high methylation rate has certain reference value for the prognosis.

BAG3 as a novel prognostic biomarker in kidney renal clear cell carcinoma correlating with immune infiltrates

PurposeBCL-2-associated athanogene 3 (BAG3) is an anti-apoptotic protein that plays an essential role in the onset and progression of multiple cancer types. However, the clinical significance of BAG3 in kidney renal clear cell carcinoma (KIRC) remains unclear.MethodsUsing Tumor IMmune Estimation Resource (TIMER), The Cancer Genome Atlas (TCGA), and Gene Expression Omnibus (GEO) database, we explored the expression, prognostic value, and clinical correlations of BAG3 in KIRC. In addition, immunohistochemistry (IHC) of HKH cohort further validated the expression of BAG3 in KIRC and its impact on prognosis. Gene Set Cancer Analysis (GSCA) was utilized to scrutinize the prognostic value of BAG3 methylation. Gene Ontology (GO) term analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene set enrichment analysis (GSEA) were used to identify potential biological functions of BAG3 in KIRC. Single-sample gene set enrichment analysis (ssGSEA) was performed to confirm the correlation between BAG3 expression and immune cell infiltration.ResultsBAG3 mRNA expression and protein expression were significantly downregulated in KIRC tissues compared to normal kidney tissues, associated with adverse clinical–pathological factors and poor clinical prognosis. Multivariate Cox regression analysis indicated that low expression of BAG3 was an independent prognostic factor in KIRC patients. GSEA analysis showed that BAG3 is mainly involved in DNA methylation and the immune-related pathways in KIRC. In addition, the expression of BAG3 is closely related to immune cell infiltration and immune cell marker set.ConclusionBAG3 might be a potential therapeutic target and valuable prognostic biomarker of KIRC and is closely related to immune cell infiltration.

A comprehensive analysis of essential meiotic endonuclease 1 to prognosis and immune infiltration in kidney renal clear cell carcinoma.

Clear cell renal cell carcinoma (ccRCC) is the most common type of cancer, and its molecular pathogenesis is unclear. In this study, we investigated the prognostic value of essential meiotic endonuclease 1 (EME1) in kidney renal clear cell carcinoma (KIRC). We downloaded the RNA-Seq expression of 526 KIRC tissues and 72 normal tissues from the TCGA database and the corresponding clinical data. The gene expression profiles associated with four clear cell renal cell carcinomas were downloaded from the GEO database for analysis. The expression of EME1 in clear renal cell carcinoma and its correlation with the clinical baseline data were analyzed. Kaplan-Meier survival curve analysis was performed to assess the relationship between EME1 and patient survival. Enrichment analysis was performed to elucidate the possible functions of EME1. We also analyzed the relationship between the EME1 expression and immune infiltration through TIMER2.0 and TISIDB online databases as well as the relationship between EME1 and common immune checkpoints. EME1 was identified as a risk factor for overall survival in clear cell renal cell carcinoma with a hazard ratio of 3.201 (95% confidence interval: 2.430-4.215; p < 0.001). EME1 was highly expressed in KIRC compared to that in normal tissues (p < 0.001) and in the worse TNM stages and late stages (stage 3/4) (p < 0.001). High EME1 expression was strongly associated with the advanced T stage (p = 0.003), advanced N stage (p = 0.002), and advanced M stage (p = 0.006). Research data on KIRC were simultaneously collected and analyzed from the GEO database, including GSE40435, GSE53000, GSE68417, and GSE53757. EME1 predicted the survival status in KIRC patients (AUC = 0.62). We further established a nomogram including the correlation between the high and low EME1 expression, and EME1 was found to contribute to the prediction of the probability of patient survival with a c-index = 0.796. Kaplan-Meier analysis revealed a lower likelihood of survival with a high EME1 expression (p < 0.001). In addition, further bioinformatics analysis suggested that EME1 may be associated with the extent of immune infiltration in KIRC. An increased expression of EME1 in KIRC is thus associated with advanced clinicopathological features, possibly acting as a potential biomarker of poor prognosis in KIRC.

Comprehensive analysis reveals dual biological function roles of EpCAM in kidney renal clear cell carcinoma

BackgroundEpithelial cell adhesion molecule (EpCAM), a well-established marker for circulating tumor cells, plays a crucial role in the complex process of cancer metastasis. The primary objective of this investigation is to study EpCAM expression in pan-cancer and elucidate its significance in the context of kidney renal clear cell carcinoma (KIRC). MethodsData obtained from the public database was harnessed for the comprehensive assessment of the EpCAM expression levels and prognostic and clinicopathological correlations in thirty-three types of cancer. EpCAM was validated in our own KIRC sequencing and immunohistochemical cohorts. Subsequently, an in-depth exploration was conducted to scrutinize the interrelationship between EpCAM and various facets, including immune cells, immune checkpoints, and chemotherapy drugs. We employed Cox regression analysis to identify prognostic immunomodulators associated with EpCAM, which were subsequently utilized in the development of a prognostic model. The model was validated in our own clinical cohort and public datasets, and compared with 137 published models. The role of EpCAM in KIRC was explored by biological function experiments in vitro. ResultsWhile EpCAM exhibited pronounced overexpression across a wide spectrum of cancer types, a notable reduction was observed in KIRC tissues. As grade increased, EpCAM expression decreased. EpCAM expression decreased in patients without metastasis. EpCAM mRNA and protein levels were used as independent, favorable prognostic factors in patients with KIRC in our own cohort. The expression of EpCAM exhibited strong associations with immune-related pathways, demonstrating an inverse correlation with the majority of immune cell types. Immune checkpoint inhibitors exert better therapeutic effects on patients with low EpCAM expression. In addition, EpCAM can be used as a drug resistance indicator and guide the clinical medication of patients with KIRC. A robust model, which had good predictive accuracy and applicability, showed significant superiority over other models. Importantly, EpCAM played the dual roles of promoting proliferation and resisting metastasis in KIRC. ConclusionIn the context of KIRC, EpCAM assumes a surprising dual role, where it not only facilitates cell proliferation but also exerts resistance against the metastatic process. EpCAM serves as a standalone prognostic marker for patients with KIRC, and related models can also effectively predict prognosis. These discoveries offer novel perspectives on the functional significance of EpCAM in the context of KIRC.

The immunoreactivity of GLI1 and VEGFA is a potential prognostic factor in kidney renal clear cell carcinoma

Kidney renal clear cell carcinoma (KIRC) is the most common type of kidney cancer and its pathogenesis is strongly associated with VHL–HIF–VEGF signaling. SHH ligand is the upstream SHH pathway regulator, while GLI1 is its major effector that stimulates as a transcription factor, i.a. expression of VEGFA gene. The aim of present study was to assess the prognostic significance of SHH, GLI1 and VEGFA immunoreactivity in KIRC tissues. The analysis included paired tumor and normal samples from 34 patients with KIRC. The immunoreactivity of SHH, GLI1 and VEGFA proteins was determined by immunohistochemical (IHC) renal tissues staining. The IHC staining results were assessed using the immunoreactive score (IRS) method which takes into account the number of cells showing a positive reaction and the intensity of the reaction. Increased GLI1 protein immunoreactivity was observed in KIRC tissues, especially in early-stage tumors, according to the TNM classification. Elevated expression of the VEGFA protein was noted primarily in high-grade KIRC samples according to the Fuhrman/WHO/ISUP scale. Moreover, a directly proportional correlation was observed between SHH and VEGFA immunoreactivity in TNM 3 + 4 and Fuhrman/ISUP/WHO 3 + 4 tumor tissues as well as in samples of patients with shorter survival. We also observed an association between shorter patient survival as well as increased and decreased immunoreactivity, of the VEGFA and GLI1, respectively. The aforementioned findings suggest that the expression pattern of SHH, GLI1 and VEGFA demonstrates prognostic potential in KIRC.

Low OGDHL expression affects the prognosis and immune infiltration of kidney renal clear cell carcinoma.

Oxoglutarate dehydrogenase-like (OGDHL) modulates glutamine metabolism to influence tumor progression. Therefore, we aimed to explore the potential role of OGDHL in the prognosis of kidney renal clear cell carcinoma (KIRC) and its effect on immune infiltration. The Cancer Genome Atlas, Tumor Immune Estimation Resource, Gene Expression Profiling Interactive Analysis, Human Protein Atlas, and The University of Alabama at Birmingham Cancer databases and the GSE53757 dataset were utilized to analyze expression difference and prognosis of OGDHL in tumor and normal tissue; diagnostic value was assessed using receiver operating characteristic curves. Correlations with clinical features and survival prognosis were analyzed. Independent prognostic factors were identified using univariate and multifactorial Cox regression analysis. We used the CIBERSORT analysis tool to discover the proportion of tumor-infiltrating immune cells (TIICs) in KIRC patients. Next, the differences in the proportion of TIICs under different OGDHL expression were analyzed. Finally, we explored the potential mechanisms by which OGDHL expression affects patient survival using Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Set Enrichment Analysis (GSEA). OGDHL expression was markedly downregulated in KIRC tissues compared to in normal tissues, and the downregulation of OGDHL expression was significantly associated with tumor progression (including tumor stage and grade) and poor prognosis. Cox regression analyses revealed OGDHL to be an independent prognostic factor for KIRC. CIBERSORT analysis showed that OGDHL expression is associated with differences in the proportion of several TIICs, particularly resting mast cells. Finally, GO and KEGG analysis showed that OGDHL was associated with extracellular matrix and epithelial cell differentiation involved in kidney development. GSEA indicated that low OGDHL was closely related to the activation of carcinogenic signaling pathways, including epithelial mesenchymal transition, tumor necrosis factor alpha and nuclear factor kappa B signaling pathway, negative regulation of apoptotic signaling, collagen formation, etc. OGDHL level can be monitored for diagnosing KIRC. Reduced expression is associated with poor prognosis and immune infiltration of KIRC. OGDHL is expected to become a new target for the treatment of KIRC.

Necroptosis-related genes are associated with prognostic features of kidney renal clear cell carcinoma

IntroductionRenal clear cell carcinoma is a common type of cancer in the adult urological system. It has a high mortality rate, with 30% of patients developing metastasis and 60% dying within 1–2 years of diagnosis. Recent advancements in tumor immunology and necroptosis have provided new insights into kidney cancer therapy. Therefore, it is crucial to identify potential targets for combining immunotherapy with necroptosis.Materials and methodsUsing the GSE168845 dataset and necroptosis-related genes, we identified genes that are differentially expressed in relation to necroptosis. We analyzed the prognostic value of these genes through differential expression analysis, prognostic analysis, and Cox regression analysis. The expression levels of the MYCN and CDKN2A genes were verified using the GSE53757 dataset. We also examined the association between the differentially expressed genes and clinicopathological features, as well as overall survival in our cohorts. In addition, we constructed a lasso Cox regression model to assess the correlation between these genes and immune score, ICP, and OCLR score. We conducted qRT-PCR to detect the expression of MYCN, CDKN2A, and ZBP1 in different samples of kidney renal clear cell carcinoma (KIRC). The expression levels of these genes were verified in a normal kidney cell line (HK-2 cells) and two KIRC cell lines (786-O, ACHN). The protein levels of MYCN and CDKN2A were detected using immunohistochemistry (IHC). SiRNA was used to silence the expression of MYCN and CDKN2A in the ACHN cell line, and wound healing assays were performed to measure cell migration.ResultsMYCN, CDKN2A, and ZBP1 were identified as necroptosis-related genes with independent prognostic value, leading to the development of a risk prognostic model. The expression of the CDKN2A gene was significantly higher in KIRC tissues compared to normal tissues, while the expression of the MYCN gene was significantly lower in KIRC tissues. The expression of MYCN and CDKN2A was associated with tumor stage, metastasis, and overall survival in our cohort. Furthermore, MYCN, CDKN2A, and ZBP1 were significantly correlated with immune score, ICP, and OCLR score. The expression levels of CDKN2A and ZBP1 were higher in KIRC cells compared to normal kidney cells, while the expression of MYCN was lower in KIRC cells. The protein expression of MYCN and CDKN2A was also higher in KIRC tissues, as confirmed by IHC. The results of the wound healing assay indicated that silencing CDKN2A inhibited cell migration, while silencing MYCN enhanced cell migration.ConclusionsMYCN and CDKN2A are potential targets and valuable prognostic biomarkers for combining immunotherapy with necroptosis in kidney renal clear cell carcinoma. CDKN2A promotes the migration of renal cancer cells, while MYCN inhibits their migration.

The hsa-miR-3613–5p, a potential oncogene correlated with diagnostic and prognostic merits in kidney renal clear cell carcinoma

MicroRNA-3613 (hsa-miR-3613–5p), a biomarker with a dual role as an oncogenic or tumor suppressor, is associated with different types of cancer. This study aimed to determine the correlation between the hsa-miR-3613–5p gene expression and Kidney renal clear cell carcinoma (KIRC). Utilizing several bioinformatics tools, we examined the expression level and clinicopathological value of hsa-miR-3613–5p in patients with KIRC compared to normal tissues. Other bioinformatic measures, including survival analysis, diagnostic merit of hsa-miR-3613–5p, downstream target prediction, potential upstream lncRNAs, network construction, and functional enrichment analysis of hsa-miR-3613–5p, were performed. We observed that overexpression of hsa-miR-3613–5p in KIRC tissues had valuable diagnostic merit and was significantly correlated with the poor overall survival of KIRC patients. We also realized a correlation between abnormal expression of hsa-miR-3613–5p and several clinical parameters such as pathological stage, race, age, and histological grades in patients with KIRC. Moreover, we constructed the most potential regulatory network of hsa-miR-3613–5p in KIRC with 17 different axes, including four pseudogenes, two lncRNAs, and three mRNAs. Besides, we uncovered six variants in the mature form of hsa-miR-3613–5p. Finally, pathway enrichment analysis demonstrated that the top-ranked pathways for hsa-miR-3613–5p are cell cycle, cell adhesion molecules (CAMs), and hepatocellular carcinoma pathways. The present report suggests that the higher expression of hsa-miR-3613–5p is associated with the progression of KIRC. Therefore, it may be considered a valuable indicator for the early detection, risk stratification, and targeted treatment of patients with KIRC.

High C1QTNF1 expression mediated by potential ncRNAs is associated with poor prognosis and tumor immunity in kidney renal clear cell carcinoma.

Background: Kidney renal clear cell carcinoma (KIRC) originates from proximal tubular cells and is the most common subtype of renal cell carcinoma. KIRC is characterized by changes in lipid metabolism, and obesity is a risk factor for it. C1q And TNF Related 1 (C1QTNF1), a novel adipokine and member of the C1q and TNF-related protein (CTRP) family, has been shown to affect the progression of various cancers. However, the role of C1QTNF1 in KIRC has not been studied. Methods: The Wilcoxon rank sum test was used to analyze the expression of C1QTNF1 in KIRC tissues and normal tissues. The relationship between clinicopathological features and C1QTNF1 levels was also examined by logistic regression and the Wilcoxon rank sum test. In addition, the effect of C1QTNF1 on the prognosis of KIRC patients was analyzed by Kaplan-Meier (KM). The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were used to analyze the potential signaling pathways and biological functions of differential genes. A nomogram was constructed to predict the prognosis of KIRC patients. Spearman correlation analysis was performed to determine the association between C1QTNF1 expression and immune cell infiltration and immune checkpoint genes. The upstream miRNAs and lncRNAs of C1QTNF1 were predicted by the ENCORI online tool. Finally, we examined the proliferation, invasion, and migration abilities of KIRC cells after C1QTNF1 knockdown. Results: The expression of C1QTNF1 in KIRC tissues was significantly higher than in normal renal tissues. Patients with higher C1QTNF1 expression had a poor prognosis, a finding supported by Kaplan-Meier survival analysis. C1QTNF1 expression was significantly correlated with TNM and pathologic stages, age, and gender (p < 0.05). The C1QTNF1 expression level was significantly correlated with immune cell infiltration and immune checkpoint genes in KIRC. Additionally, high C1QTNF1 expression was associated with poor prognosis in stage I and II, T1 and T2, T3 and T4, N0, and M0 patients (HR > 1, p < 0.05). The calibration diagram shows that the C1QTNF1 model has effective predictive performance for the survival of KIRC patients. Knockdown of C1QTNF1 inhibited KIRC cell proliferation, cell migration, and cell invasion. In addition, CYTOR and AC040970.1/hsa-miR-27b-3p axis were identified as the most likely upstream ncRNA-related pathways of C1QTNF1 in KIRC. Conclusion: In conclusion, our study suggests that high expression of C1QTNF1 is associated with KIRC progression and immune infiltration. The increased expression of C1QTNF1 suggests a poor prognosis in KIRC patients.

Expression profiles and functional prediction of histone acetyltransferases of the MYST family in kidney renal clear cell carcinoma

BackgroundHistone acetyltransferases (HATs) of the MYST family are associated with a variety of human cancers. However, the relationship between MYST HATs and their clinical significance in kidney renal clear cell carcinoma (KIRC) has not yet been evaluated.MethodsThe bioinformatics method was used to investigate the expression patterns and prognostic value of MYST HATs. Western blot was used to detect the expression of MYST HATs in KIRC.ResultsThe expression levels of MYST HATs except KAT8 (KAT5, KAT6A, KAT6B, and KAT7) were significantly reduced in KIRC tissues compared to normal renal tissues, and the western blot results of the KIRC samples also confirmed the result. Reduced expression levels of MYST HATs except KAT8 were significantly associated with high tumor grade and advanced TNM stage in KIRC, and showed a significant association with an unfavorable prognosis in patients with KIRC. We also found that the expression levels of MYST HATs were closely related to each other. Subsequently, gene set enrichment analysis showed that the function of KAT5 was different from that of KAT6A, KAT6B and KAT7. The expression levels of KAT6A, KAT6B and KAT7 had significant positive correlations with cancer immune infiltrates such as B cells, CD4+ T cells and CD8+ T cells.ConclusionsOur results indicated that MYST HATs, except KAT8, play a beneficial role in KIRC.

TROAP Promotes the Proliferation, Migration, and Metastasis of Kidney Renal Clear Cell Carcinoma with the Help of STAT3

Kidney renal clear cell carcinoma (KIRC) is a subtype of renal cell carcinoma that threatens human health. The mechanism by which the trophinin-associated protein (TROAP)–an important oncogenic factor–functions in KIRC has not been studied. This study investigated the specific mechanism by which TROAP functions in KIRC. TROAP expression in KIRC was analyzed using the RNAseq dataset from the Cancer Genome Atlas (TCGA) online database. The Mann–Whitney U test was used to analyze the expression of this gene from clinical data. The Kaplan–Meier method was used for the survival analysis of KIRC. The expression level of TROAP mRNA in the cells was detected using qRT-PCR. The proliferation, migration, apoptosis, and cell cycle of KIRC were detected using Celigo, MTT, wound healing, cell invasion assay, and flow cytometry. A mouse subcutaneous xenograft experiment was designed to demonstrate the effect of TROAP expression on KIRC growth in vivo. To further investigate the regulatory mechanism of TROAP, we performed co-immunoprecipitation (CO-IP) and shotgun liquid chromatography–tandem mass spectrometry (LC-MS). TCGA-related bioinformatics analysis showed that TROAP was significantly overexpressed in KIRC tissues and was related to higher T and pathological stages, and a poor prognosis. The inhibition of TROAP expression significantly reduced the proliferation of KIRC, affected the cell cycle, promoted cell apoptosis, and reduced cell migration and invasion. The subcutaneous xenograft experiments showed that the size and weight of the tumors in mice were significantly reduced after TROAP-knockdown. CO-IP and post-mass spectrometry bioinformatics analyses revealed that TROAP may combine with signal transducer and activator of transcription 3 (STAT3) to achieve tumor progression in KIRC; this was verified by functional recovery experiments. TROAP may regulate KIRC proliferation, migration, and metastasis by binding to STAT3.

Downregulation of RAB17 have a poor prognosis in kidney renal clear cell carcinoma and its expression correlates with DNA methylation and immune infiltration

BackgroundRAB17 is one of the RAB family members. It has been reported to be closely associated with a variety of tumors and has different roles in various tumors. However, the effect of RAB17 in KIRC remains unclear. Materials and methodsWe analyzed the differential expression of RAB17 in kidney renal clear cell carcinoma (KIRC) tissues and normal tissues using the public databases. The prognostic role of RAB17 in KIRC was analyzed using the Cox regression methods, and a prognostic model was constructed based on the results of the Cox analysis. In addition, further analysis of RAB17 in KIRC was performed in relation to genetic alterations, DNA methylation m6A methylation and immune infiltration. Finally, RAB17 mRNA and protein expression levels were analyzed in tissue samples (KIRC tissues and normal tissues) and cell lines (normal renal tubular cell and KIRC cells), and in vitro functional assays were performed. ResultsRAB17 was low-expressed in KIRC. Downregulation of RAB17 expression is correlated with unfavorable clinicopathological characteristics and a worse prognosis in KIRC. The RAB17 gene alteration in KIRC was primarily characterized by copy number alteration. Six CpG sites of RAB17 DNA methylation levels are higher in KIRC tissues than in normal tissues, and are correlated with RAB17 mRNA expression levels, showing a significant negative correlation. cg01157280 site DNA methylation levels are associated with pathological stage and overall survival, and it may be the only CpG site with independent prognostic significance. Functional mechanism analysis revealed that RAB17 is closely associated with immune infiltration. RAB17 expression was found to be negatively correlated with most immune cell infiltration according to two different methods. Furthermore, most immunomodulators were significantly negatively correlated with RAB17 expression, and significantly positively correlated with RAB17 DNA methylation levels. RAB17 was significantly low expression in KIRC cells and KIRC tissues. In vitro, silencing of RAB17 promoted KIRC cell migration. ConclusionRAB17 can be used as a potential prognostic biomarker for patients with KIRC and for assessing immunotherapy response.

Bioinformatics Prediction and Experimental Verification Identify CAB39L as a Diagnostic and Prognostic Biomarker of Kidney Renal Clear Cell Carcinoma.

Background and Objectives: Calcium-binding protein 39-like (CAB39L) has been reported to be downregulated and possessed diagnostic and prognostic values in several types of cancer. However, the clinical value and mechanism of CAB39L in kidney renal clear cell carcinoma (KIRC) remain unclear. Materials and Methods: Bioinformatics analysis was conducted using different databases including TCGA, UALCAN, GEPIA, LinkedOmics, STRING, and TIMER. One-way variance analysis and t-test were chosen to investigate the statistical differences of CAB39L expression in KIRC tissues with different clinical characteristics. The receiver operating characteristic (ROC) curve was chosen to assess the discriminatory capacity of CAB39L. Kaplan-Meier curves were employed for assessing the influence of CAB39L on the progression-free survival (PFS), disease-specific survival (DSS), and overall survival (OS) of KIRC patients. The independent prognostic significance of clinical parameters for OS such as CAB39L expression in KIRC patients was estimated by Cox analysis. A series of in vitro functional experiments and Western blot (WB) and immunohistochemistry (IHC) were used to validate the relative protein expression and function of CAB39L. Results: The mRNA and protein levels of CAB39L were relatively downregulated in KIRC samples. Meanwhile, hypermethylation of the CAB39L promoter region was possibly associated with its low expression in KIRC. The ROC curve showed that the mRNA expression of CAB39L had a strong diagnostic value for both early and late KIRC. Kaplan-Meier survival curves indicated that a higher mRNA level of CAB39L predicted good PFS, DSS, and OS. The mRNA expression of CAB39L was an independent prognostic factor (hazard ratio = 0.6, p = 0.034) identified by multivariate Cox regression analysis. The Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analysis exhibited that CAB39L was mainly associated with substance and energy metabolism. Finally, overexpression of CAB39L impaired the proliferation and metastasis of KIRC cells in vitro. Conclusions: CAB39L possesses prognostic and diagnostic capacity in KIRC.

Integrated bioinformatic analysis and cell line experiments reveal the significant role of the novel immune checkpoint TIGIT in kidney renal clear cell carcinoma.

T cell immunoglobulin and ITIM domain (TIGIT) is a widely concerned immune checkpoint, which plays an essential role in immunosuppression and immune evasion. However, the role of TIGIT in normal organ tissues and renal clear cell carcinoma is unclear. We aim to identify the critical role of TIGIT in renal clear cell carcinoma and find potential targeted TIGIT drugs. Data retrieved from the GTEX database and TCGA database was used to investigate the expression of TIGIT in normal whole-body tissues and abnormal pan-cancer, then the transcriptome atlas of patients with kidney renal clear cell carcinoma (KIRC) in the TCGA database were applied to distinguish the TIGIT related features, including differential expression status, prognostic value, immune infiltration, co-expression, and drug response of sunitinib an anti-PD1/CTLA4 immunotherapy in KIRC. Furthermore, we constructed a gene-drug network to discover a potential drug targeting TIGIT and verified it by performing molecular docking. Finally, we conducted real-time polymerase chain reaction (PCR) and assays for Transwell migration and CCK-8 to explore the potential roles of TIGIT. TIGIT showed a moderate expression in normal kidney tissues and was confirmed as an essential prognostic factor that was significantly higher expressed in KIRC tissues, and high expression of TIGIT is associated with poor OS, PFS, and DSS in KIRC. Also, the expression of TIGIT was closely associated with the pathological characteristics of the tumor, high expression of TIGIT in KIRC was observed with several critical functions or pathways such as apoptosis, BCR signaling, TCR signaling etal. Moreover, the expression of TIGIT showed a strong positive correlation with infiltration of CD8+ T cells and Tregs and a positive correlation with the drug sensitivity of sunitinib simultaneously. Further Tide ips score analysis and submap analysis reveal that patients with high TIGIT expression significantly show a better response to anti-PD1 immunotherapy. Following this, we discovered Selumetinib and PD0325901 as potential drugs targeting TIGIT and verified the interaction between these two drugs and TIGIT protein by molecular docking. Finally, we verified the essential role of TIGIT in the proliferation and migration functions by using KIRC cell lines. TIGIT plays an essential role in tumorigenesis and progression in KIRC. High expression of TIGIT results in poor survival of KIRC and high drug sensitivity to sunitinib. Besides, Selumetinib and PD0325901 may be potential drugs targeting TIGIT, and combined therapy of anti-TIGIT and other treatments show great potential in treating KIRC.

C1QC is a prognostic biomarker with immune-related value in kidney renal clear cell carcinoma.

Background: Kidney renal clear cell carcinoma (KIRC) is a representative histologic subtype of renal cell carcinoma (RCC). RCC exhibits a strong immunogenicity with a prominent dysfunctional immune infiltration. Complement C1q C chain (C1QC) is a polypeptide in serum complement system and is involved in tumorigenesis and the modulation of tumor microenvironment (TME). However, researches have not explored the effect of C1QC expression on prognosis and tumor immunity of KIRC. Methods: The difference in a wide variety of tumor tissues and normal tissues in terms of the C1QC expression was detected using TIMER and TCGA portal databases, and further validation of protein expression of C1QC was conducted via Human Protein Atlas. Then, the associations of C1QC expression with clinicopathological data and other genes were studied with the use of UALCAN database. Subsequently, the association of C1QC expression with prognosis was predicted by searching the Kaplan-Meier plotter database. A protein-protein interaction (PPI) network with the Metascape database was built using STRING software, such that the mechanism underlying the C1QC function can be studied in depth. The TISCH database assisted in the evaluation of C1QC expression in different cell types in KIRC at the single-cell level. Moreover, the association of C1QC and the infiltration level of tumor immune cell was assessed using TIMER platform. The TISIDB website was selected to deeply investigate the Spearman correlation between C1QC and immune-modulator expression. Lastly, how C1QC affected the cell proliferation, migration, and invasion in vitro was assessed using knockdown strategies. Results: KIRC tissues had notably upregulated C1QC level in comparison with adjacent normal tissues, with showed a positive relevance to clinicopathological features including tumor stage, grade, and nodal metastasis, and a negative relevance to clinical prognosis in KIRC. C1QC knockdown inhibited KIRC cell proliferation, migration, and invasion, as indicated by the results of the in vitro experiment. Furthermore, functional and pathway enrichment analysis demonstrated that C1QC was involved in immune system-related biological processes. According to single-cell RNA analysis, C1QC exhibited a specific upregulation in macrophages cluster. Additionally, there was an obvious association of C1QC and a wide variety of tumor-infiltrating immune cells in KIRC. Also, high C1QC expression presented inconsistent prognosis in different enriched immune cells subgroups in KIRC. Immune factors might contribute to C1QC function in KIRC. Conclusion: C1QC is qualified to predict KIRC prognosis and immune infiltration biologically. Targeting C1QC may bring new hope for the treatment of KIRC.

ETNK2 Low-Expression Predicts Poor Prognosis in Renal Cell Carcinoma with Immunosuppressive Tumor Microenvironment.

The ethanolamine kinase 2 (ETNK2) gene is implicated in carcinogenesis, but its expression and involvement in kidney renal clear cell carcinoma (KIRC) remain unknown. Initially, we conducted a pan-cancer study in which we searched the Gene Expression Profiling Interactive Analysis, the UALCAN, and the Human Protein Atlas databases to determine the expression level of the ETNK2 gene in KIRC. The Kaplan-Meier curve was then used to calculate the overall survival (OS) of KIRC patients. We then used the differentially expressed genes (DEGs) and enrichment analysis to explain the mechanism of the ETNK2 gene. Finally, the immune cell infiltration analysis was performed. Although the ETNK2 gene expression was lower in KIRC tissues, the findings illustrated a link between the ETNK2 gene expression and a shorter OS time for KIRC patients. DEGs and enrichment analysis revealed that the ETNK2 gene in KIRC involved multiple metabolic pathways. Finally, the ETNK2 gene expression has been linked to several immune cell infiltrations. According to the findings, the ETNK2 gene plays a crucial role in tumor growth. It can potentially serve as a negative prognostic biological marker for KIRC by modifying immune infiltrating cells.

Integrated analysis of the relation to tumor immune microenvironment and predicted value of Stonin1 gene for immune checkpoint blockage and targeted treatment in kidney renal clear cell carcinoma

BackgroundStonin1 (STON1) is an endocytic protein but its role in cancer remains unclear. Here, we investigated the immune role of STON1 in kidney renal clear cell carcinoma (KIRC).MethodsWe undertook bioinformatics analyses of the expression and clinical significance of STON1 in KIRC through a series of public databases, and the role of STON1 in the tumor microenvironment and the predictive value for immunotherapy and targeted treatment in KIRC were identified with R packages. STON1 expression was validated in clinical KIRC tissues as well as in KIRC and normal renal tubular epithelial cells.ResultsThrough public databases, STON1 mRNA was found to be significantly downregulated in KIRC compared with normal controls, and decreased STON1 was related to grade, TNM stage, distant metastasis and status of KIRC patients. Compared with normal controls, STON1 was found to be downregulated in KIRC tissues and cell lines. Furthermore, OncoLnc, Kaplan–Meier, and GEPIA2 analyses also suggested that KIRC patients with high STON1 expression had better overall survival. The high STON1 group with enriched immune cells had a more favorable prognosis than the low STON1 group with decreased immune cells. Single sample Gene Set Enrichment Analysis and Gene Set Variation Analysis indicated that STON1 creates an immune non-inflamed phenotype in KIRC. Moreover, STON1 was positively associated with mismatch repair proteins and negatively correlated with tumor mutational burden. Furthermore, Single sample Gene Set Enrichment Analysis algorithm and Pearson analysis found that the low STON1 group was more sensitive to immune checkpoint blockage whereas the high STON1 group was relatively suitable for targeted treatment.ConclusionsDecreased STON1 expression in KIRC leads to clinical progression and poor survival. Mechanically, low STON1 expression is associated with an aberrant tumor immune microenvironment. Low STON1 is likely to be a favorable indicator for immunotherapy response but adverse indicator for targeted therapeutics in KIRC.

Construction and verification of a novel prognostic risk model for kidney renal clear cell carcinoma based on immunity-related genes.

Background: Currently, there are no useful biomarkers or prognostic risk markers for the diagnosis of kidney renal clear cell carcinoma (KIRC), although recent research has shown that both, the onset and progression of KIRC, are substantially influenced by immune-associated genes (IAGs). Objective: This work aims to create and verify the prognostic value of an immune risk score signature (IRSS) based on IAGs for KIRC using bioinformatics and public databases. Methods: Differentially expressed genes (DEGs) related to the immune systems (IAGs) in KIRC tissues were identified from The Cancer Genome Atlas (TCGA) databases. The DEGs between the tumor and normal tissues were identified using gene ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) enrichment analyses. Furthermore, a prognostic IRSS model was constructed and its prognostic and predictive performance was analyzed using survival analyses and nomograms. Kidney renal papillary cell carcinoma (KIRP) sets were utilized to further validate this model. Results: Six independent immunity-related genes (PAEP, PI3, SAA2, SAA1, IL20RB, and IFI30) correlated with prognosis were identified and used to construct an IRSS model. According to the Kaplan-Meier curve, patients in the high-risk group had significantly poorer prognoses than those of patients in the low-risk group in both, the verification set (p <0.049; HR = 1.84; 95% CI = 1.02-3.32) and the training set (p < 0.001; HR = 3.12, 95% CI = 2.23-4.37). The numbers of regulatory T cells (Tregs) were significantly positively correlated with the six immunity-related genes identified, with correlation coefficients were 0.385, 0.415, 0.399, 0.451, 0.485, and 0.333, respectively (p <0.001). Conclusion: This work investigated the association between immune infiltration, immunity-related gene expression, and severity of KIRC to construct and verify a prognostic risk model for KIRC and KIRP.

Reconsidering the role of receptors for SARS‐CoV‐2 in clear cell renal cell carcinoma: Friends or foes

Reconsidering the role of receptors for SARS‐CoV‐2 in clear cell renal cell carcinoma: Friends or foes