Integrated molecular analysis of clear-cell renal cell carcinoma

Disclosing the development and focus of sequencing and omics studies in kidney neoplasm research

BACKGROUND

Kidney cancer is a worldwide prevalent urological malignancy and the leading cause of death. Sequencing and omics studies play a crucial role in unraveling its molecular mechanisms and diagnostic, prognostic, and therapeutic relevance. This study aims to offer a comprehensive review of the evolving trends and hotspots of sequencing and omics studies in kidney neoplasms.

METHODS

We conducted the retrieval of scientific publications on sequencing and omics studies in kidney neoplasms from the Web of Science Core Collection (WoSCC) on July 3, 2023. The R-based bibliometrix package, VOSviewer, and CiteSpace were utilized to conduct the holistic bibliometric analysis to obtain objective and data-driven results. A comprehensive consultation of papers was then proceeded for an in-depth review.

RESULTS

Our investigation yielded a dataset containing 1260 records from 509 sources, with 43,404 references, from 1960 to 2023. Publication and citation frequencies have been consistently growing. In country analysis, China and the USA led the research, displaying substantial collaboration. Notable contributors like TEH BT, SAUTER G, and FUTREAL PA shaped this research landscape. Key journals such as PLoS One, Cancer Research, and New England Journal of Medicine actively participated in and significantly influenced this field. Distinguished publications and references were also revealed, along with their historical citation and co-citation relationships. A panel of keywords, including RCC, biomarker, and multi-omics data were identified and clustered.

CONCLUSION

We obtained a profound understanding of the developing trends and hotspots of research investigating sequencing and omics studies in kidney neoplasms. Specifically, we have highlighted three hotspots: "explore molecular mechanisms of RCC pathogenesis, progression, and metastasis", "identify molecular biomarkers of RCC for diagnosis, prognosis, and therapeutics", "investigate tumor heterogeneity and tailor personalized therapeutic strategies for RCC". Hopefully, our study will serve as a valuable reference for scientific researchers and clinical practitioners.

Integrative multi-omics reveal NSUN2 facilitates glycolysis and histone lactylation-driven immune evasion in renal carcinoma

Clear cell renal carcinoma (ccRCC) is the most prevalent and aggressive subtype of kidney cancer. Targeting ccRCC metabolism is a promising therapeutic strategy, and some metabolic targets are currently undergoing clinical trials. Here, we collected multiple ccRCC clinical cohorts, including bulk RNA sequencing and single-cell sequencing datasets, to investigate mitochondrial metabolic genes' prognostic and therapeutic potential. Integrating 10 machine learning algorithms, we constructed 117 predictive models, with the optimal model selected and defined as Mitoscore for patient stratification and treatment. Furthermore, NSUN2, an RNA 5-methylcytosine (m5C) methyltransferase, was identified as the most important gene in the model and selected for further gene function experiments in vitro and in vivo. NSUN2 promoted cell proliferation, migration, and invasion; reprogrammed glycolysis metabolism and histone lactylation levels via maintaining NEO1 mRNA stability. In addition, NSUN2 increased PD-L1 expression in tumor cells via the MYC/POM121/CD274 axis in a lactylation-dependent manner. Knockdown of NSUN2 enhanced CD8 T cell killing effects in vitro, along with TNF-α + T cell infiltration in vivo. These results highlight that mitochondrial genes are optional therapeutic targets and prognostic markers; NSUN2 promotes mitochondrial glycolysis and histone lactylation in an m5C-dependent manner, thereby resulting in PD-L1-mediated immune escape, which elucidates novel NSUN2-mediated crosstalk between glycolysis and immune evasion.

Metabolic reprogramming and immune microenvironment profiling in clear cell renal cell carcinoma: implications for prognosis, targeted therapy, and drug resistance

Clear cell renal cell carcinoma (ccRCC) is the most prevalent form of kidney cancer, distinguished by intricate interactions between metabolic reprogramming, immune microenvironment dynamics, and genetic mutations. In this detailed investigation, we analyzed the ccRCC cohort from The Cancer Genome Atlas (TCGA) alongside 81 metabolic signaling pathways from the KEGG database. By utilizing Gene Set Variation Analysis (GSVA), we performed hierarchical clustering of patients based on their metabolic pathway activity profiles, identifying three distinct clusters with notable differences in pathway activity and survival outcomes. Cluster 1 displayed high metabolic activity and more favorable survival outcomes, while Cluster 3 was characterized by low metabolic activity and poorer prognosis. Clinical comparisons revealed significant disparities in gender, histological stage, and survival status, with Cluster 3 exhibiting a higher proportion of patients at advanced stages and those who had passed away. Genetically, Cluster 1 showed the highest mutation burden, with prominent mutations in genes such as VHL and PBRM1. Biological process analysis indicated that pathways like organic carboxylic acid metabolism and ATP synthesis were upregulated in Cluster 1 but suppressed in Cluster 3. Machine learning models (GBM, CoxBoost, and LASSO regression) enabled the identification of four pivotal genes-BCAT1, IL4I1, ACADM, and ACADSB-which were subsequently used to construct a multifactorial Cox regression model. This model successfully stratified patients into high- and low-risk groups, correlating with marked differences in immune activities. The high-risk group showed elevated expression of chemokines, TNF, and HLA molecules. Drug sensitivity analysis suggested that AKT inhibitor III was more effective in the low-risk cohort, while Bortezomib might be more beneficial for high-risk patients. Additionally, a clinical prediction model integrating risk scores and clinical factors demonstrated strong predictive power for patient survival. Methylation profiling of the core genes via the UALCAN platform revealed distinct epigenetic signatures in ccRCC, providing deeper insight into the disease's molecular mechanisms. This study contributes to a more comprehensive understanding of ccRCC and proposes valuable directions for personalized treatment strategies and enhanced patient management.

Angiogenesis related gene signatures predict prognosis and guide therapeutic strategies in renal clear cell carcinoma

Kidney tumors are hypervascular tumors with crucial antiangiogenic effects in tumor therapy. This study aimed to develop a predictive model for kidney renal clear cell carcinoma (KIRC) by utilizing angiogenesis-related genes to formulate targeted therapy and immunotherapy strategies. Angiogenesis-related genes were screened via the GeneCard and Molecular Signatures Database (MSigDB). The KIRC data downloaded from The Cancer Genome Atlas (TCGA) were randomly divided into an experimental cohort and a validation cohort. In the experimental cohort, a risk score prediction model was constructed through successive analyses via univariate Cox regression, LASSO regression, and multivariate Cox regression. Receiver operating characteristic (ROC) curves were employed to assess the sensitivity of the model's predictions. The model's stability and generalizability were subsequently validated in both the validation cohort and the E-MTAB-1980 cohort. Subsequently, the TCGA-KIRC dataset was stratified into two distinct groups: a localized tumor cohort and a progression/metastasis cohort, based on tumor staging criteria. The efficacy of the prognostic prediction model was evaluated within each subgroup. A nomogram model was developed in conjunction with each independent prognostic factor to accurately predict patient outcomes. Additionally, single-cell and intercellular communication analyses were conducted via KIRC single-cell data obtained from the Gene Expression Omnibus (GEO) database. The effects of immunotherapy and targeted therapy on patients were predicted via prognostic modeling. A total of 260 angiogenesis-related genes were identified through screening in the GeneCards and Molecular Signatures Database(MSigDB). We subsequently developed a risk model comprising five genes: MEOX2, PLG, PROX1, TEK, and TIMP1. Survival analysis indicated that the prognosis for high-risk patients was significantly poorer than that for low-risk patients (P < 0.001), and the model demonstrated satisfactory accuracy in predicting 1-, 3-, and 5-year survival rates. This finding was further validated in both internal and external validation cohorts. The model demonstrated applicability for prognostic predictions in both the localized tumor cohort and the progression/metastasis cohort, with proficiency in forecasting the prognosis of patients diagnosed with metastatic renal cancer. The AUC values for 1, 3, and 5 years were recorded at 0.691, 0.709, and 0.773, respectively. We successfully constructed a nomogram model to facilitate accurate prognostic predictions for patients. Analysis of single-cell data revealed that PLG was expressed predominantly in tumor cell clusters, whereas TEK was highly expressed primarily in pericytes. TIMP1 was found to be highly expressed in vascular smooth muscle cells. In contrast, MEOX2 and PROX1 were highly expressed in specific cell clusters but presented low expression levels across the overall cell population. Cell communication analysis indicated that the modeling gene TEK was involved in the angiogenic pathway, with the interaction between the ligand ANGPT2 and the receptor ITGA5-ITGB1 being particularly prominent in this study. Furthermore, the immune dysfunction and rejection scores for high-risk patients within the non-localized renal cancer cohort were markedly elevated compared to those observed in the low-risk group. In terms of targeted pharmacological intervention, individuals classified in the low-risk group exhibited a heightened sensitivity to sorafenib. The KIRC prognostic prediction model, which is based on five angiogenesis-related genes, demonstrated reliable performance, indicating that high-risk patients have a significantly poorer prognosis than low-risk patients do. The developed nomogram model effectively visualizes and accurately predicts patient prognosis. It is essential to highlight that individuals diagnosed with low-risk metastatic KIRC may experience greater advantages from the administration of immunotherapy and sorafenib.

Pulmonary Metastasectomy in Renal Cell Carcinoma

Recent advances in immunotherapy and targeted therapy have resulted in survival rates as high as 90% at 1 year in metastatic renal cell carcinoma patients; however, sustained response and ultimate cure is rarely achieved with systemic therapy alone (complete response rates remain <5%), and progression of disease at distant sites is common. Pulmonary metastasectomy is recommended as a component of multimodal management in patients with favorable-risk or intermediate-risk classification and can be associated with excellent survival if complete resection is obtained.

Mefloquine Suppresses Metastasis in Renal Cell Carcinoma Through Targeting SPC25

Renal cell carcinoma (RCC) is the third most common malignant tumor in the urinary system, often presenting with distant metastases at diagnosis. Approximately one-quarter of patients undergoing nephrectomy experience distant recurrence. Despite the recent advancements in combination-targeted and immune checkpoint inhibitor therapies, the development of new therapeutic strategies and the identification of biomarkers for metastatic risk remain crucial. The study found that high SPC25 expression is closely associated with poor clinical outcomes, and knocking down SPC25 significantly inhibits tumor cell proliferation and migration. Non-targeted metabolomics analysis also revealed that SPC25 knockdown reduces tumor cell activity, resulting in a low-invasive state. Additionally, this study utilized high-throughput molecular docking to screen small molecule drugs targeting SPC25, aiming to find drugs that inhibit RCC metastasis. The research discovered that mefloquine, at concentrations that do not significantly kill tumor cells, can markedly inhibit RCC metastasis. It was the first to report that mefloquine achieves its anti-metastatic effects by binding to SPC25 and inhibiting epithelial-mesenchymal transition. These results suggest that SPC25 has the potential to serve as an early biomarker for metastatic risk in RCC and highlight a novel strategy where mefloquine inhibits RCC metastasis through SPC25 binding, offering new avenues to improve the prognosis of RCC patients.

Liquid Biopsy as a New Tool for Diagnosis and Monitoring in Renal Cell Carcinoma

Renal cell carcinoma (RCC) presents a significant diagnostic challenge, particularly in small renal masses. The search for non-invasive screening methods and biomarkers has directed research toward liquid biopsy, which focuses on microRNAs (miRNAs), exosomes, and circulating tumor cells (CTCs). miRNAs are small non-coding RNA molecules that show considerable dysregulation in RCC, and they have potential for both diagnostic and prognostic applications. Research has highlighted their utility on biofluids, such as plasma, serum, and urine, in detecting RCC and characterizing its subtypes. Promising miRNA signatures have been associated with overall survival, suggesting their potential importance in the management of RCC. Exosomes, which carry a variety of molecular components, including miRNAs, are emerging as valuable biomarkers, whereas CTCs, released from primary tumors into the bloodstream, provide critical information on cancer progression. However, translation of these findings into clinical practice requires additional validation and standardization through large-scale studies and robust evidence. Although there are currently no approved diagnostic tests for RCC, the future potential of liquid biopsy in monitoring, treatment decision-making, and outcome prediction in patients with this disease is significant. This review examined and discussed recent developments in liquid biopsy for RCC, assessing both the strengths and limitations of these approaches for managing this disease.

Adverse reactions of four multi-targeted tyrosine kinase inhibitors: a descriptive analysis of the WHO-VigiAccess database

Background

The introduction of multi-targeted tyrosine kinase inhibitors (MTKIs) such as axitinib, lenvatinib, sorafenib, and sunitinib has greatly broadened the available treatment options for Renal Cell Carcinoma (RCC). The study aims to compare the nature of the adverse reactions associated with these four MTKIs to identify which medication poses the least risk for personalized patient management, thus enabling more accurate clinical drug oversight.

Methods

Employing a retrospective descriptive analysis methodology, this research concentrated on four commercially available MTKIs. Reports pertaining to these medications were sourced from the WHO-VigiAccess database. The data gathering process involved collecting comprehensive information on various parameters, such as age demographics, gender, and the geographical distribution of patients associated with the ADR reports. Furthermore, the study explored disease systems and symptoms that were documented alongside the adverse reactions, as outlined in the annual ADR reports produced by the WHO. To assess the relationship between these four MTKIs and the linked AEs, both the Proportional Reporting Ratio (PRR) and the Reported Odds Ratio (ROR) were utilized.

Results

At the time of the search, a total of 123,818 AEs associated with the four MTKIs had been documented in the VigiAccess database. The common ADRs for these four MTKIs include diarrhoea, fatigue, death, hypertension, nausea, asthenia, weight decreased, and vomiting. Gastrointestinal disorders and general disorders and administration site conditions emerged as the SOCs with the highest number of adverse signals, both ranking first in terms of frequency. The elevated ROR (1.08) and PRR (1.06) values associated with gastrointestinal disorders in patients treated with sorafenib suggest a higher incidence of such adverse events compared to those observed with axitinib, lenvatinib, and sunitinib.

Conclusion

Recent comparative observational research suggests that the ADR reports submitted to the WHO and the FDA for these medications highlight both common and specific ADRs. It is essential for clinical practitioners to develop personalized treatment strategies that consider the adverse effects linked to different medications, alongside the unique circumstances of their patients, thus encouraging the responsible use of these MTKIs.

ELOC-Mutated Renal Cell Carcinoma is a Rare Indolent Tumor With Distinctive Genomic Characteristics

ELOC-mutated renal cell carcinoma (ELOC-RCC) is a subtype of RCC first recognized by the World Health Organization in 2022, molecularly defined by the presence of ELOC mutations and the lack of VHL mutations. Here, we present an institutional series of ELOC-RCC and provide an in-depth genetic comparison to VHL-null clear cell RCC (VHL-ccRCCs). Among 1209 RCCs in our institutional cytogenetics database, we identified 16 candidate cases that were originally classified as ccRCC and exhibited monosomy 8 and intact chromosome 3p. Seven of these 16 candidate cases were diagnosed as ELOC-RCCs based on histomorphology, immunohistochemistry, and whole-exome sequencing results. By contrast, ELOC-RCCs had a simpler karyotype of monosomy 8 with few other alterations. Adding 6 additional ELOC-RCC cases identified from The Cancer Genome Atlas cohort, all 13 ELOC-RCCs exhibited biallelic ELOC inactivation without VHL mutations. These ELOC mutations (Y79C/L/S/N, E92K, A106D, and C112Vfs∗3) were all located within or close to the VHL-binding domains in ELOC protein; 69% of the ELOC-RCC cases exhibited its characteristic histomorphology. Compared with stage- and grade-matched VHL-ccRCCs, patients with ELOC-RCCs had superior overall survival (hazard ratio, 0.32; 95% confidence intervals, 0.16-0.61; P = .02) and progression-free survival (hazard ratio, 0.16; 95% confidence intervals, 0.06-0.42; P = 0.04). ELOC-RCCs had significantly fewer somatic copy number alterations and a greater abundance of the mutational signature SBS1 than VHL-ccRCCs. ELOC-RCCs lacked common chromosomal alterations or gene mutations seen in ccRCC, including PBRM1, SETD2, BAP1, TSC1, TSC2, or mTOR. Most ELOC-RCCs had linear phylogenetic trees with clonal and truncal ELOC mutations, whereas additional alterations to ELOC or 8q losses occurred as a subclonal event. Although 11 of 13 ELOC-RCCs were confined to the kidney, 2 ELOC-RCCs were high-stage and exhibited a large solid alveolar pattern, tumor necrosis, more somatic copy number alterations, and an additional monoallelic VHL copy loss. Taken together, ELOC-RCCs exhibit distinctive genomic features and indolent behavior in general, supporting it as an independent diagnostic entity.

Molecular landscape of clear cell renal cell carcinoma: targeting the Wnt/β-catenin signaling pathway

Clear cell renal cell carcinoma (ccRCC) is the most common subtype of renal cell carcinoma and is characterized by a complex molecular landscape driven by genetic and epigenetic alternations. Among the crucial signaling pathways implicated in ccRCC, the Wnt/β-catenin pathway plays a significant role in tumor progression and prognosis. This review delves into the molecular basis of ccRCC, highlighting the genetic and epigenetic modifications that contribute to its pathogenesis. We explore the significance of the Wnt/β-catenin pathway, focusing on its role in disease development, particularly the nuclear transport of β-catenin and its activation and downstream effects. Furthermore, we examine the role of antagonist genes in regulating this pathway within the context of ccRCC, providing insights into potential therapeutic targets. Dysregulation of this pathway, which is characterized by abnormal activation and nuclear translocation of β-catenin, plays a significant role in promoting tumor growth and metastasis. We explore the intricate molecular aspects of ccRCC, with a particular emphasis on this topic, underscoring the role of the pathway and emphasizing the importance and relevance of antagonist genes. Understanding the intricate interplay between these molecular mechanisms is crucial for developing innovative strategies to improve ccRCC treatment and patient outcomes.

Loss of SETD2 in wild-type VHL clear cell renal cell carcinoma sensitizes cells to STF-62247 and leads to DNA damage, cell cycle arrest, and cell death characteristic of pyroptosis

Loss of chromosome 3p and loss of heterogeneity of the von Hippel-Lindau (VHL) gene are common characteristics of clear cell renal cell carcinoma (ccRCC). Despite frequent mutations on VHL, a fraction of tumors still grows with the expression of wild-type (WT) VHL and evolve into an aggressive subtype. Additionally, mutations on chromatin-modifying genes, such as the gene coding for the histone methyltransferase SET containing domain 2 (SETD2), are essential to ccRCC evolution. We previously identified STF-62247, a small molecule first discovered as a synthetically lethal molecule for VHL-deficient cells by blocking late stages of autophagy. This study investigated how other commonly mutated genes in ccRCC could impact the response to STF-62247. We showed that SETD2 inactivation in ccRCC cells expressing WT-VHL became vulnerable to STF-62247, as indicated by decreases in cell proliferation and survival. Furthermore, activation of the DNA damage response pathway leads to the loss of M-phase inducer phosphatase 1 (CDC25A) and cell cycle arrest in S phase. Cleavage of both caspase-3 and gasdermin E suggests that STF-62247 eliminates WT-VHL ccRCC cells through pyroptosis specifically when SETD2 is inactivated.

Clinical Outcomes and Targeted Genomic Analysis of Renal Cell Carcinoma Brain Metastases Treated with Stereotactic Radiosurgery

BACKGROUND

Molecular profiles of renal cell carcinoma (RCC) brain metastases (BMs) are not well characterized. Effective management with locoregional therapies, including stereotactic radiosurgery (SRS), is critical as systemic therapy advancements have improved overall survival (OS).

OBJECTIVE

To identify clinicogenomic features of RCC BMs treated with SRS in a large patient cohort.

DESIGN, SETTING, AND PARTICIPANTS

A single-institution retrospective analysis was conducted of all RCC BM patients treated with SRS from January 1, 2010 to March 31, 2021.

INTERVENTION

SRS for RCC BMs.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Next-generation sequencing was performed to identify gene alterations more prevalent in BM patients. Clinical factors and genes altered in ≥10% of samples were assessed per patient using Cox proportional hazards models and per individual BM using clustered competing risks regression with competing risk of death.

RESULTS AND LIMITATIONS

Ninety-one RCC BM patients underwent SRS to 212 BMs, with a median follow-up of 38.8 mo for patients who survived. The median intracranial progression-free survival and OS were 7.8 (interquartile range [IQR] 5.7-11) and 21 (IQR 16-32) mo, respectively. Durable local control of 83% was achieved at 12 mo after SRS, and 59% of lesions initially meeting the radiographic criteria for progression at 3-mo evaluation would be considered to represent pseudoprogression at 6-mo evaluation. A comparison of genomic alterations at both the gene and the pathway level for BM+ patients compared with BM- patients revealed phosphoinositide 3-kinase (PI3K) pathway alterations to be more prevalent in BM+ patients (43% vs 16%, p = 0.001, q = 0.01), with the majority being PTEN alterations (17% vs 2.7%, p = 0.003, q = 0.041).

CONCLUSIONS

To our knowledge, this is the largest study investigating genomic profiles of RCC BMs and the only such study with annotated intracranial outcomes. SRS provides durable in-field local control of BMs. Recognizing post-SRS pseudoprogression is crucial to ensure appropriate management. The incidence of PI3K pathway alterations is more prevalent in BM+ patients than in BM- patients and warrants further investigation in a prospective setting.

PATIENT SUMMARY

We examined the outcomes of radiotherapy for the treatment of brain metastases in kidney cancer patients at a single large referral center. We found that radiation provides good control of brain tumors, and certain genetic mutations may be found more commonly in patients with brain metastasis.

Mutations in tumor suppressor genes Vhl and Rassf1a cause DNA damage, chromosomal instability and induce gene expression changes characteristic of clear cell renal cell carcinoma

RASSF1A is frequently biallelically inactivated in clear cell renal cell carcinoma (ccRCC) due to loss of chromosome 3p and promoter hypermethylation. Here we investigated the cellular and molecular consequences of single and combined deletion of the Rassf1a and Vhl tumor suppressor genes to model the common ccRCC genotype of combined loss of function of RASSF1A and VHL. In mouse embryonic fibroblasts and in primary kidney epithelial cells, double deletion of Rassf1a and Vhl caused chromosomal segregation defects and increased formation of micronuclei, demonstrating that pVHL and RASSF1A function to maintain genomic integrity. Combined Rassf1a and Vhl deletion in kidney epithelial cells in vivo increased proliferation and caused mild tubular disorganization, but did not lead to the development of kidney tumors. Single cell RNA-sequencing unexpectedly revealed that Rassf1a or Vhl deletion both induce the expression of an overlapping set of genes in a sub-population of proximal tubule cells. Many of these genes are also upregulated in the Vhl/Trp53/Rb1 deficient mouse model of ccRCC. In other subsets of proximal tubule cells, combined Vhl/Rassf1a deletion induced the expression of additional genes that were not upregulated in each of the single knockouts. The expression of the human homologues of Rassf1a-regulated genes correlate negatively with RASSF1 expression levels in human ccRCC. Our results suggest that the loss of RASSF1A function establishes a ccRCC-characteristic gene expression pattern.

Clear Cell Renal Cell Carcinoma: A Comprehensive Review of its Histopathology, Genetics, and Differential Diagnosis

Clear cell renal cell carcinoma (ccRCC) is the predominant subtype of renal epithelial tumor, accounting for roughly 2% of all malignancies. Clinically, it often presents in the sixth to seventh decade of life, predominantly in men. Pathologically, these tumors exhibit a distinctive golden yellow cut surface, usually arising from the renal cortex. Their microscopic features are characterized by solid and nested architectures of cells with clear or eosinophilic granular cytoplasm and a prominent vascular network. A hallmark genetic feature is the inactivation of the VHL gene situated on chromosome 3p25. The majority of ccRCCs are sporadic (over 95%), typically presenting as a single mass; and a small percentage have a hereditary basis, often associated with VHL disease, characterized by multiple bilateral tumors with an earlier onset. Immunohistochemically, ccRCC tumors express PAX8, CA9 box like pattern, and CD10 but are generally negative for AMACR (35% positive) and KRT7 (15% positive). The prognosis of ccRCC is largely determined by its TNM stage, ISUP/WHO nucleolar grade, and the presence of specific aggressive features. This review article delves into the detailed gross, microscopic, molecular, and clinical features of ccRCC, offering comprehensive insights into its diagnosis, management, and prognosis.

Retinoid X receptor γ predicts the prognosis and is associated with immune infiltration in kidney renal clear cell carcinoma: a qRT-PCR, TCGA and in silico research

BACKGROUND

Kidney clear cell carcinoma (KIRC) stands as one of the most prevalent primary malignant tumors, showcasing significant heterogeneity within the urological system. However, the precise molecular mechanisms underpinning tumorigenesis in KIRC remain elusive. While Retinoid X receptor γ (RXRG) has been implicated in various diseases and human cancers, its specific role in KIRC remains undetermined. This research aimed to investigate the involvement of RXRG in KIRC pathogenesis.

METHODS

Quantitative real-time polymerase chain reaction was performed to evaluate the expression levels of RXRG in KIRC. Utilizing RNA-seq data and corresponding clinicopathological information from The Cancer Genome Atlas (TCGA) database, we embarked on an analysis to ascertain the prognostic significance of RXRG in KIRC. Furthermore, bioinformatics analyses were employed to delineate the preliminary molecular mechanisms through which RXRG operates in KIRC tumorigenesis.

RESULTS

Our findings revealed a significant downregulation of RXRG in KIRC tumor tissues compared to normal kidney tissues, as evidenced in local and TCGA cohorts. Diminished RXRG expression correlated with adverse clinicopathological characteristics, including larger tumor size, higher clinical stage, and advanced histologic grade. Cox regression analyses unveiled that reduced RXRG expression was associated with poorer overall survival (OS) and disease-free survival (DFS) rates in KIRC patients. Bioinformatics analyses indicated that the RXRG-related differentially expressed genes (DEGs) were involved in tumorigenesis and metabolism by regulating a series of signaling pathways. Using ssGSEA, we found that RXRG expression was significantly associated with NK cells and macrophages.

CONCLUSION

Our study provides new insights and evidence that RXRG is involved in the tumorigenesis of KIRC and may be a suitable target for immunotherapy in KIRC.

The genomic landscape of metastatic clear-cell renal cell carcinoma and its prognostic value: a comprehensive analysis of a large real-world clinico-genomic database

BACKGROUND

Translating findings on the genomic landscape of metastatic clear-cell renal cell carcinoma (mccRCC) into clinical practice remains challenging. A better understanding of the molecular features of mccRCC could identify a prognostic and/or predictive role for ccRCC genomic alterations.

PATIENTS AND METHODS

In this real-world observational study based on the nationwide (US-based) de-identified Flatiron Health-Foundation Medicine, Inc. clinico-genomic database (FH-FMI-CGDB), we investigate the frequency and co-occurrence of genomic alterations in mccRCC patients and assess their prognostic role. Patients (n = 858) were adults diagnosed with mccRCC, with FH electronic health records between 2011 and 2022.

RESULTS

The top 10 mutated genes were VHL (73.9%), PBRM1 (42.4%), SETD2 (25.3%), CDKN2A (20.0%), BAP1 (16.4%), CDKN2B (16.0%), KDM5C (14.5%), TP53 (12.9%), PTEN (11.7%), and TERT (9.2%). Eight genes showed prognostic value: CDKN2A, CDKN2B, TP53, PTEN, NF2, PIK3CA, and MTAP were linked to worse prognosis, whereas PBRM1 was associated with better overall survival (OS). Two of the three identified gene clusters had prognostic value: cluster 1 (VHL, SETD2, PBRM1, KDM5C, NFE2L2) correlated with better OS [adjusted hazard ratio (aHR) 0.63, P < 0.001], whereas cluster 3 (CDKN2A, CDKN2B, BAP1, NF2, MTAP) correlated with shorter OS (aHR 1.36, P = 0.023).

CONCLUSION

We identified eight genes and two gene clusters with prognostic significance for mccRCC. Future research will explore the predictive value of gene clusters in various treatments.

Tissue-Based Biomarkers Important for Prognostication and Management of Genitourinary Tumors, Including Surrogate Markers of Genomic Alterations

A better understanding of the molecular alterations that underlie urologic malignancies and advances in targeted therapies has impacted classification, prognostication, and treatment. In bladder tumors, these advances include the development of antibody-drug conjugates targeting nectin-4 and Trop-2, as well as human epidermal growth factor receptor 2 and immunotherapy. In prostate cancer, assessment of the percentage of Gleason pattern 4, presence of cribriform glands, and molecular alterations, including PTEN and mismatch repair protein loss, have become standard for clinical care. In renal malignancies, alterations in TSC1/2, mammalian target of rapamycin, anaplastic lymphoma kinase, and other genes impact classification and therapeutic decisions.

What Is New in Pathologic Diagnosis and Classification of the Common Renal Cell Neoplasms?

Diagnostic challenges remain among the common renal cell carcinoma (RCC) subtypes. High-grade clear cell RCC may have deceptive patterns, for example BAP1-deficient tumors. Subtyping type 1 and 2 papillary RCC is no longer recommended, as former type 2 tumors may now be contain other diagnostic entities, such as FH-deficient RCC, MITF family RCC, or others. Clear cell papillary tumor is no longer considered carcinoma due to its highly favorable behavior. However, imperfect examples are best considered clear cell RCC. Oncocytic renal neoplasm of low malignant potential has been proposed as a borderline category in the absence of overt malignant features.

Machine learning identification of a novel vasculogenic mimicry-related signature and FOXM1's role in promoting vasculogenic mimicry in clear cell renal cell carcinoma

BACKGROUND

Clear Cell Renal Cell Carcinoma (ccRCC), the predominant subtype of renal cell carcinoma (RCC), ranks among the most common malignancies worldwide. Vasculogenic mimicry (VM) plays a pivotal role in tumor progression, being closely linked with heightened chemoresistance and adverse prognosis in cancer patients. Nonetheless, the broader impact of vasculogenic mimicry-related genes (VRGs) on ccRCC patient prognosis, tumor microenvironment characteristics, and treatment response remains incompletely understood.

METHODS

Consensus clustering identified VRG-associated subtypes. We developed a machine learning framework integrating 12 algorithms to establish a consistent VM-related signature (VRG_score). The predictive value of VRG_score for ccRCC prognosis and treatment response was assessed. FOXM1's clinical relevance was explored using the UCLCAN database. FOXM1 expression in tumor and adjacent tissues was assessed using Western Blotting, IHC, RNA-seq, and Chip-qPCR methods, and its regulatory mechanism was confirmed.

RESULTS

We examined VRG mutation and expression patterns in ccRCC at the gene level, identifying two distinct molecular clusters. A consensus VRG_score was formulated using a machine learning computational framework and Cox regression, displaying strong predictive power for prognosis and clinical translation. Additionally, FOXM1 was found to be upregulated in ccRCC, correlating with clinical pathological features and positively regulating PYCR1, thereby activating the PI3K/AKT/mTOR signaling pathway and promoting VM formation.

CONCLUSION

This study constructed a VM-related signature and revealed that FOXM1 promotes VM formation in renal cell carcinoma through the PYCR1-PI3K/AKT/mTOR signaling axis, serving as a prognostic indicator and potential therapeutic target.

Glycogen metabolism genes as a molecular signature for subtyping, prognostic prediction, and immunotherapy selection in clear cell renal cell carcinoma

Glycogen accumulation is a typical feature in clear cell renal cell carcinoma (ccRCC). It has been reported that glycogen metabolism-related genes can promote the progression of ccRCC, but its role in molecular typing, prognosis, immune infiltration, and immunotherapy response has rarely been reported. We applied an unsupervised clustering approach for molecular typing of ccRCC. The least absolute shrinkage and selection operator regression (LASSO) was used for prognostic model construction. The robustness of the model is evaluated by multicenter mutual verification. Weighted gene co-expression network analysis (WGCNA) was used to explore potential biological mechanisms. RT-qPCR was used to identify mRNA relative expression. We found ccRCC can be divided into two subtypes based on glycogen metabolism-related genes, and the prognosis of patients between the two subtypes is significantly different. Furthermore, we constructed a prognostic model for ccRCC patients based on glycogen metabolism-related genes using LASSO algorithm. We found that the model has a strong prognostic effect. Subsequently, we explored the underlying mechanisms through WGCNA and found that the model is associated with immune-related signaling pathways. Finally, we also found that this prognostic model can be used as a marker of response to immunotherapy in patients with advanced ccRCC. In conclusion, glycogen metabolism-related genes have critical value in molecular typing and prognosis evaluation of ccRCC.

KDM5C and KDM5D mutations have different consequences in clear cell renal cell carcinoma cells

KDM5C is commonly mutated in clear cell renal cell carcinomas (ccRCC) in men but rarely in women. Introducing KDM5C mutation into two male and two female KDM5C wild-type ccRCC cell lines caused different phenotypes and non-overlapping transcriptional consequences, indicative of context-dependent functions of KDM5C. We identify that loss of the Y chromosome, harbouring the KDM5C homologue KDM5D, occurs in most male KDM5C mutant ccRCCs. Mutation of KDM5D in male 786-O cells prevented xenograft tumour formation and this phenotype was unexpectedly rescued by co-mutation of KDM5C, consistent with the co-occurrence of KDM5C mutation and loss of the Y chromosome in ccRCC. Transcriptional analyses showed that KDM5C and KDM5D regulate the expression of both overlapping as well as distinct sets of genes. While KDM5C and KDM5D bind to at least some overlapping genomic sites, gene expression changes induced by KDM5C or KDM5D mutation are apparently unrelated to the direct functions of these proteins at the relevant gene promoters or enhancers. Our findings identify similarities and differences in KDM5C and KDM5D functions, challenging the idea that KDM5D in male cells functions equivalently to the second KDM5C allele in female cells, and implicate an interplay between KDM5C mutation and Y chromosome loss in ccRCC development in men.

Integrated multi-omics analysis identifies a machine learning-derived signature for predicting prognosis and therapeutic vulnerability in clear cell renal cell carcinoma

AIMS

Clear cell renal cell carcinoma (ccRCC) shows considerable variation within and between tumors, presents varying treatment responses among patients, possibly due to molecular distinctions. This study utilized a multi-center and multi-omics analysis to establish and validate a prognosis and treatment vulnerability signature (PTVS) capable of effectively predicting patient prognosis and drug responsiveness.

MATERIALS AND METHODS

To address this complexity, we constructed an integrative multi-omics analysis using 10 clustering algorithms on ccRCC patient data. Afterwards, we applied bootstrapping in univariate Cox regression and the Boruta algorithm to pinpoint clinically relevant genes. Based on this, we developed a robust PTVS using seven machine learning algorithms.

KEY FINDINGS

Our analysis revealed two distinct ccRCC subtypes with differential prognostic implications, notably identifying subtype 2 with poorer outcomes. Patients in the low PTVS group exhibited superior prognosis statistics and an augmented sensitivity to immunotherapy, features consistent with a 'hot tumor' phenotype. Conversely, individuals within the high PTVS group exhibited diminished prognosis statistic and restricted advantages from immunotherapy. Importantly, the PTVS holds future potential as a notable biomarker for guiding personalized treatment strategies, with four prospective targets (CTSK, XDH, PKMYT1, and EGLN2) indicating therapeutic promise in patients scoring high on PTVS.

SIGNIFICANCE

The integrative analysis of multi-omics data profoundly enhances the molecular stratification of ccRCC, underscoring far-reaching impact of such comprehensive profiling on its therapeutic strategies.

Tumor-initiating and metastasis-initiating cells of clear-cell renal cell carcinoma

Clear-cell renal cell carcinoma (ccRCC) is the most common subtype of kidney malignancy. ccRCC is considered a major health concern worldwide because its numbers of incidences and deaths continue to rise and are predicted to continue rising in the foreseeable future. Therefore new strategy for early diagnosis and therapeutics for this disease is urgently needed. The discovery of cancer stem cells (CSCs) offers hope for early cancer detection and treatment. However, there has been no definitive identification of these cancer progenitors for ccRCC. A majority of ccRCC is characterized by the loss of the von Hippel-Lindau (VHL) tumor suppressor gene function. Recent advances in genome analyses of ccRCC indicate that in ccRCC, tumor-initiating cells (TICs) and metastasis-initiating cells (MICs) are two distinct groups of progenitors. MICs result from various genetic changes during subclonal evolution, while TICs reside in the stem of the ccRCC phylogenetic tree of clonal development. TICs likely originate from kidney tubule progenitor cells bearing VHL gene inactivation, including chromatin 3p loss. Recent studies also point to the importance of microenvironment reconstituted by the VHL-deficient kidney tubule cells in promoting ccRCC initiation and progression. These understandings should help define the progenitors of ccRCC and facilitate early detection and treatment of this disease.

Kinomic profiling to predict sunitinib response of patients with metastasized clear cell Renal Cell Carcinoma

INTRODUCTION

Treatment with Sunitinib, a potent multitargeted receptor tyrosine kinase inhibitor (TKI) has increased the progression-free survival (PFS) and overall-survival (OS) of patients with metastasized renal cell carcinoma (mRCC). With modest OS improvement and variable response and toxicity predictive and/or prognostic biomarkers are needed to personalize patient management: Prediction of individual TKI therapy response and resistance will increase successful treatment outcome while reducing unnecessary drug use and expense. The aim of this study was to investigate whether kinase activity analysis can predict sunitinib response and/or toxicity using tissue samples obtained from primary clear cell RCC (ccRCC) from a cohort of clinically annotated patients with mRCC receiving sunitinib as first-line treatment.

MATERIALS AND METHODS

EuroTARGET partners collected ccRCC and matched normal kidney tissue samples immediately after surgery, snap-frozen and stored at -80°C until use. Phosphotyrosine-activity profiling was performed using PamChip® peptide microarrays (144 peptides derived from known phosphorylation sites in Protein Tyrosine Kinase substrates) of lysed tissue samples (5 µg protein input) of 163 mRCC patients. Evolve software Was used to analyze kinome profiles and Bionavigator was used for unsupervised and supervised clustering. The kinexus kinase predictor (www.phosphonet.ca) was used to analyze the peptide lists within the clusters.

RESULTS

Kinome data was available from 94 patients who received sunitinib as 1st-line treatment and had complete follow-up of their clinical data (PFS, OS and toxicity) for at least 6 months. Matched normal tissue was available from 14 mRCC patients. Supervised clustering of basal kinome activity could correctly classify mRCC patients with PFS >9 months versus PFS<9 months with an accuracy of 61 %. Unsupervised hierarchical clustering revealed 3 major clusters related to immune signaling, VEGF pathway, and immune signaling/cell adhesion. Basal kinase activity levels of patients with short PFS were substantially higher compared to patients who experienced extended PFS.

DISCUSSION/CONCLUSION

Based on kinase levels ccRCC tumors can be subdivided into 3 clusters which may reflect the aggressiveness of these tumors. The accuracy of response prediction of 61 % based on basal kinase levels is too low to justify implementation. STK assays may help to predict sunitinib toxicity and guide clinical management. Additionally, it is possible that mRCC patients with an immune kinase signature are better checkpoint inhibitor candidates, but this needs to be studied.

Hypoxia-inducible transcription factors: architects of tumorigenesis and targets for anticancer drug discovery

Hypoxia-inducible factors (HIFs) play a pivotal role as master regulators of tumor survival and growth, controlling a wide array of cellular processes in response to hypoxic stress. Clinical data correlates upregulated HIF-1 and HIF-2 levels with an aggressive tumor phenotype and poor patient outcome. Despite extensive validation as a target in cancer, pharmaceutical targeting of HIFs, particularly the interaction between α and βsubunits that forms the active transcription factor, has proved challenging. Nonetheless, many indirect inhibitors of HIFs have been identified, targeting diverse parts of this pathway. Significant strides have also been made in the development of direct inhibitors of HIF-2, exemplified by the FDA approval of Belzutifan for the treatment of metastatic clear cell renal carcinoma. While efforts to target HIF-1 using various therapeutic modalities have shown promise, no clinical candidates have yet emerged. This review aims to provide insights into the intricate and extensive role played by HIFs in cancer, and the ongoing efforts to develop therapeutic agents against this target.

GXYLT2: an emerging therapeutic target and predictive biomarker for anti-PD-1 efficacy in clear cell renal cell carcinoma

There are studies reporting that glucoside xylosyltransferase 2 (GXYLT2) has a role in promoting tumor progression, but its role in clear cell renal cell carcinoma (ccRCC) remains unclear. In this study, RT-qPCR and western blotting were employed to detect the expression level of GXYLT2. RNA interference assays were used to knock down GXYLT2. CCK-8, wound healing assays, clone formation assays, and Transwell assays were utilized to investigate the function of GXYLT2. Bioinformatics analysis was used to explore the tumor microenvironment and potential biological mechanisms. We found that the expression level of GXYLT2 in ccRCC was higher than that in adjacent normal renal tissues. Patients with high GXYLT2 expression have worse clinical outcomes. Knockdown of GXYLT2 inhibits the proliferation, invasion, migration, and clone formation ability of ccRCC cells. Enrichment analysis uncovered that GXYLT2 participates in Wnt, cell cycle, and actin cytoskeleton regulation signaling pathways. After receiving anti-PD-1 therapy, patients with high GXYLT2 expression had longer progression-free survival compared with those with low GXYLT2 expression. In conclusion, GXYLT2 is a novel potential therapeutic target for ccRCC. Meanwhile, GXYLT2 can be used as a novel marker for predicting immunotherapeutic response.

Kidney cancer: From tumor biology to innovative therapeutics

Renal cell carcinoma (RCC) constitutes the most frequent kidney cancer of the adult population and one of the most lethal malignant tumors worldwide. RCC often presents without early symptoms, leading to late diagnosis. Prognosis varies widely based on the stage of cancer at diagnosis. In the early-stage, localized RCC has a relatively good prognosis, while advanced or metastatic RCC has a poor outcome. Obesity, smoking, genetic mutations and family history are all considered risk factors for RCC, while inherited disorders, such as Tuberous Sclerosis and von Hippel-Lindau syndrome, are causally associated with RCC development. Genetic screening, deep sequencing analysis, quantitative proteomics and immunostaining analysis on RCC tissues, biological fluids and blood samples have been employed to identify novel biomarkers, predisposing factors and therapeutic targets for RCC with important clinical implications for patient treatment. Combined approaches of gene-targeting strategies coupled to a deep functional analysis of cancer cell biology, both in vitro and in appropriate animal models of RCC, significantly contributed to identify and characterize relevant pathogenic mechanisms underlying development and progression of RCC. These studies provided also important cues for the generation of novel target-specific therapeutics that selectively restore deranged cancer cell signalling and dysfunctional immune checkpoints, positively impacting on the survival rate of treated RCC patients. In this review, we will describe the recent discoveries concerning the most relevant pathogenic mechanisms of RCC and will highlight novel therapeutic strategies that interrupt oncogenic pathways and restore immune defences in RCC patients.

Survival improvement over time in renal cell carcinoma treated with nephrectomy: A longitudinal propensity score-matched study

OBJECTIVE

Surgical treatment for renal cell carcinoma (RCC) has drastically evolved for the past 30 years. However, survival outcomes of RCC according to times have not been fully elucidated, especially in the real-world setting. This study aimed to assess the survival improvement over time in RCC treated with nephrectomy by analyzing a longitudinal cohort using propensity score matching (PSM).

METHODS

We retrospectively reviewed 960 patients with RCC who underwent radical or partial nephrectomy between 1981 and 2018. Patients were divided into two groups according to the time of surgery (1981-1999 vs. 2000-2018). Using PSM, overall survival (OS), cancer-specific survival (CSS), and recurrence-free survival (RFS) were compared between the two groups.

RESULTS

Overall, 255 and 705 patients underwent surgery in the earlier (1981-1999) and recent (2000-2018) eras, and PSM derived a matched cohort of 466 patients (233 patients per each group). All patients in the earlier era cohort received open surgeries, whereas about a half (47.4%) of patients in the recent era cohort received minimally-invasive (laparoscopic/robotic) surgeries. After PSM, 137 (29.4%) patients developed recurrence, 105 (22.5%) died of RCC, and 113 (24.2%) died from other causes, with a median follow-up period of 90 months. The recent era cohort had significantly longer OS, CSS, and RFS than the earlier era cohort.

CONCLUSIONS

Patients with RCC treated in the recent era (2000-2018) showed significantly longer survival than those treated in the earlier era (1981-1999). The improved survival might be attributable to the prevalence of minimally-invasive (laparoscopic/robotic) surgeries.

Integrated RNA sequencing analysis and machine learning identifies a metabolism-related prognostic signature in clear cell renal cell carcinoma

The connection between metabolic reprogramming and tumor progression has been demonstrated in an increasing number of researches. However, further research is required to identify how metabolic reprogramming affects interpatient heterogeneity and prognosis in clear cell renal cell carcinoma (ccRCC). In this work, single-cell RNA sequencing (scRNA-seq) based deconvolution was utilized to create a malignant cell hierarchy with metabolic differences and to investigate the relationship between metabolic biomarkers and prognosis. Simultaneously, we created a machine learning-based approach for creating metabolism-related prognostic signature (MRPS). Gamma-glutamyltransferase 6 (GGT6) was further explored for deep biological insights through in vitro experiments. Compared to 51 published signatures and conventional clinical features, MRPS showed substantially higher accuracy. Meanwhile, high MRPS-risk samples demonstrated an immunosuppressive phenotype with more infiltrations of regulatory T cell (Treg) and tumour-associated macrophage (TAM). Following the administration of immune checkpoint inhibitors (ICIs), MRPS showed consistent and strong performance and was an independent risk factor for overall survival. GGT6, an essential metabolic indicator and component of MRPS, has been proven to support proliferation and invasion in ccRCC. MRPS has the potential to be a highly effective tool in improving the clinical results of patients with ccRCC.

Expression pattern of cancer-associated cellular senescence genes in clear cell renal cell carcinoma distinguishes tumor subclasses with clinical implications

Clear cell renal cell carcinoma (ccRCC) is a highly lethal subtype of renal cancer. Accumulating evidence suggests cellular senescence impacts tumor development and progression. This study aimed to identify ccRCC subtypes based on a cellular senescence gene signature and assess their clinical relevance. Using hierarchical clustering on the TCGA-KIRC dataset, two senescence-related subtypes were identified and validated in independent datasets. These subtypes exhibited distinct dysregulation of cancer-related pathways, including the p53 pathway. The C2 subtype was associated with poorer overall survival, higher tumor grade and stage, low hemoglobin, and elevated platelet and serum calcium levels. Patients with the C2 subtype also had lower endothelial cell infiltration, indicating reduced benefit from anti-PD-1 immunotherapy. A nomogram based on these subtypes effectively predicted 1-, 3-, and 5-year survival outcomes. These findings highlight two distinct senescence-related ccRCC subtypes that correlate with prognosis and therapy response, offering insights for personalized treatment strategies.

The Human Pathology Atlas for deciphering the prognostic features of human cancers

BACKGROUND

Cancer is one of the leading causes of mortality worldwide, highlighting the urgent need for a deeper molecular understanding and the development of personalized treatments. The present study aims to establish a solid association between gene expression and patient survival outcomes to enhance the utility of the Human Pathology Atlas for cancer research.

METHODS

In this updated analysis, we examined the expression profiles of 6918 patients across 21 cancer types. We integrated data from 10 independent cancer cohorts, creating a cross-validated, reliable collection of prognostic genes. We applied systems biology approach to identify the association between gene expression profiles and patient survival outcomes. We further constructed prognostic regulatory networks for kidney renal clear cell carcinoma (KIRC) and liver hepatocellular carcinoma (LIHC), which elucidate the molecular underpinnings associated with patient survival in these cancers.

FINDINGS

We observed that gene expression during the transition from normal to tumorous tissue exhibited diverse shifting patterns in their original tissue locations. Significant correlations between gene expression and patient survival outcomes were identified in KIRC and LIHC among the major cancer types. Additionally, the prognostic regulatory network established for these two cancers showed the indicative capabilities of the Human Pathology Atlas and provides actionable insights for cancer research.

INTERPRETATION

The updated Human Pathology Atlas provides a significant foundation for precision oncology and the formulation of personalized treatment strategies. These findings deepen our understanding of cancer biology and have the potential to advance targeted therapeutic approaches in clinical practice.

FUNDING

The Knut and Alice Wallenberg Foundation (72110), the China Scholarship Council (Grant No. 202006940003).

Therapeutic Strategies to Improve the Treatment of Pleural Mesothelioma

Pleural mesothelioma is a rare neoplastic disease with aggressive features. Patient survival is poor due to the lack of early symptoms and the absence of effective therapeutic strategies. The development of pleural mesothelioma is mainly associated to asbestos exposure and related chronic inflammation. From a molecular-based perspective, this disease is a heterogeneous tumor lacking actionable alterations. The median overall survival of patients affected by this tumor does not exceed 16 months from diagnosis. Molecular and biochemical approaches have shown that this disease is characterized by resistance to drug-induced apoptosis associated with the activation of cell survival pathways and expression of anti-apoptotic proteins. Thus, there is an urgent need to develop efficient and safe therapeutic strategies. Here, we review the pharmacological options available for the treatment of this disease with specific reference to the antitumor agents used in systemic therapies. In addition, novel pharmacological approaches, such as drug delivery tools, to improve pleural mesothelioma treatment are discussed.

HIF1α Plays a Crucial Role in the Development of TFE3-Rearranged Renal Cell Carcinoma by Orchestrating a Metabolic Shift Toward Fatty Acid Synthesis

Tumor development often requires cellular adaptation to a unique, high metabolic state; however, the molecular mechanisms that drive such metabolic changes in TFE3-rearranged renal cell carcinoma (TFE3-RCC) remain poorly understood. TFE3-RCC, a rare subtype of RCC, is defined by the formation of chimeric proteins involving the transcription factor TFE3. In this study, we analyzed cell lines and genetically engineered mice, demonstrating that the expression of the chimeric protein PRCC-TFE3 induced a hypoxia-related signature by transcriptionally upregulating HIF1α and HIF2α. The upregulation of HIF1α by PRCC-TFE3 led to increased cellular ATP production by enhancing glycolysis, which also supplied substrates for the TCA cycle while maintaining mitochondrial oxidative phosphorylation. We crossed TFE3-RCC mouse models with Hif1α and/or Hif2α knockout mice and found that Hif1α, rather than Hif2α, is essential for tumor development in vivo. RNA-seq and metabolomic analyses of the kidney tissues from these mice revealed that ketone body production is inversely correlated with tumor development, whereas de novo lipid synthesis is upregulated through the HIF1α/SREBP1-dependent mechanism in TFE3-RCC. Our data suggest that the coordinated metabolic shift via the PRCC-TFE3/HIF1α/SREBP1 axis is a key mechanism by which PRCC-TFE3 enhances cancer cell metabolism, promoting tumor development in TFE3-RCC.

Mitochondrial respiratory complex II is altered in renal carcinoma

BACKGROUND

Renal cell carcinoma (RCC) is a disease typified by anomalies in cell metabolism. The function of mitochondria, including subunits of mitochondrial respiratory complex II (CII), in particular SDHB, are often affected. Here we investigated the state and function of CII in RCC patients.

METHODS

We evaluated tumour tissue as well as the adjacent healthy kidney tissue of 78 patients with RCC of different histotypes, focusing on their mitochondrial function. As clear cell RCC (ccRCC) is by far the most frequent histotype of RCC, we focused on these patients, which were grouped based on the pathological WHO/ISUP grading system to low- and high-grade patients, indicative of prognosis. We also evaluated mitochondrial function in organoids derived from tumour tissue of 7 patients.

RESULTS

ccRCC tumours were characterized by mutated von Hippel-Lindau gene and high expression of carbonic anhydrase IX. We found low levels of mitochondrial DNA, protein and function, together with CII function in ccRCC tumour tissue, but not in other RCC types and non-tumour tissues. Mitochondrial content increased in high-grade tumours, while the function of CII remained low. Tumour organoids from ccRCC patients recapitulated molecular characteristics of RCC tissue.

CONCLUSIONS

Our findings suggest that the state of CII, epitomized by its assembly and SDHB levels, deteriorates with the progressive severity of ccRCC. These observations hold the potential for stratification of patients with worse prognosis and may guide the exploration of targeted therapeutic interventions.

Structure and function of the lysine methyltransferase SETD2 in cancer: From histones to cytoskeleton

SETD2 is known to be the unique histone methyltransferase responsible for the trimethylation of the lysine 36 of histone H3 thus generating H3K36me3. This epigenetic mark is critical for transcriptional activation and elongation, DNA repair, mRNA splicing, and DNA methylation. Recurrent SETD2-inactivating mutations and altered H3K36me3 levels are found in cancer at high frequency and numerous studies indicate that SETD2 acts as a tumor suppressor. Recently, SETD2 was further shown to methylate non-histone proteins particularly the cytoskeletal proteins tubulin and actin with subsequent impacts on cytoskeleton structure, mitosis and cell migration. Herein, we provide a review of the role of SETD2 in different cancers with special emphasis on the structural basis of the functions of this key lysine methyltransferase. Moreover, beyond the role of this enzyme in epigenetics and H3K36me3-dependent processes, we highlight the putative role of "non-epigenetic/H3K36me3" functions of SETD2 in cancer, particularly those involving the cytoskeleton.

The ubiquitin ligase STUB1 suppresses tumorigenesis of renal cell carcinomas through regulating YTHDF1 stability

STIP1 homology and U-box protein 1 (STUB1), a crucial member of the RING family E3 ubiquitin ligase, serve dual roles as an oncogene and a tumor suppressor in various human cancers. However, the role and mechanism of STUB1 in clear cell renal cell carcinoma (ccRCC) remain poorly defined. Here, we identified YTHDF1 as a novel STUB1 interaction partner using affinity purification mass spectrometry. Furthermore, we revealed that STUB1 promotes the ubiquitination and degradation of YTHDF1. Consequently, STUB1 depletion leads to YTHDF1 upregulation in renal cancer cells. Functionally, STUB1 depletion promoted migration and invasion of ccRCC cells in a YTHDF1-dependent manner. Additionally, the depletion of STUB1 also increased the tumorigenic potential of ccRCC in a xenograft model. Importantly, STUB1 expression is downregulated in ccRCC tissues, and its low expression level correlates with advanced tumor stage and poor overall survival in ccRCC patients. Taken together, these findings reveal that STUB1 inhibits the tumorigenicity of ccRCC by regulating YTHDF1 stability.

The Significance of Aldehyde Dehydrogenase 1 in Cancers

The goal of this paper is to discuss the role of ALDH isozymes in different cancers, review advances in ALDH1-targeting cancer therapies, and explore a mechanism that explains how ALDH expression becomes elevated during cancer development. ALDH is often overexpressed in cancer, and each isoform has a unique expression pattern and a distinct role in different cancers. The abnormal expression of ALDHs in different cancer types (breast, colorectal, lung, gastric, cervical, melanoma, prostate, and renal) is presented and correlated with patient prognosis. ALDH plays a significant role in various cellular functions, such as metabolism, oxidative stress response, detoxification, and cellular differentiation. Among the ALDH families, ALDH1 has gained considerable attention as a cancer stem cell (CSC) marker due to its significant role in the maintenance of stemness and the differentiation of stem cells (SCs), along with its involvement in tumorigenesis. A description of the cellular mechanisms and physiology of ALDH1 that underlies cancer development is provided. Moreover, current advances in ALDH1-targeting cancer therapies are discussed.

Integrated machine learning reveals the role of tryptophan metabolism in clear cell renal cell carcinoma and its association with patient prognosis

BACKGROUND

Precision oncology's implementation in clinical practice faces significant constraints due to the inadequacies in tools for detailed patient stratification and personalized treatment methodologies. Dysregulated tryptophan metabolism has emerged as a crucial factor in tumor progression, encompassing immune suppression, proliferation, metastasis, and metabolic reprogramming. However, its precise role in clear cell renal cell carcinoma (ccRCC) remains unclear, and predictive models or signatures based on tryptophan metabolism are conspicuously lacking.

METHODS

The influence of tryptophan metabolism on tumor cells was explored using single-cell RNA sequencing data. Genes involved in tryptophan metabolism were identified across both single-cell and bulk-cell dimensions through weighted gene co-expression network analysis (WGCNA) and its single-cell data variant (hdWGCNA). Subsequently, a tryptophan metabolism-related signature was developed using an integrated machine-learning approach. This signature was then examined in multi-omics data to assess its associations with patient clinical features, prognosis, cancer malignancy-related pathways, immune microenvironment, genomic characteristics, and responses to immunotherapy and targeted therapy. Finally, the genes within the signature were validated through experiments including qRT-PCR, Western blot, CCK8 assay, and transwell assay.

RESULTS

Dysregulated tryptophan metabolism was identified as a potential driver of the malignant transformation of normal epithelial cells. The tryptophan metabolism-related signature (TMRS) demonstrated robust predictive capability for overall survival (OS) and progression-free survival (PFS) across multiple datasets. Moreover, a high TMRS risk score correlated with increased tumor malignancy, significant metabolic reprogramming, an inflamed yet dysfunctional immune microenvironment, heightened genomic instability, resistance to immunotherapy, and increased sensitivity to certain targeted therapeutics. Experimental validation revealed differential expression of genes within the signature between RCC and adjacent normal tissues, with reduced expression of DDAH1 linked to enhanced proliferation and metastasis of tumor cells.

CONCLUSION

This study investigated the potential impact of dysregulated tryptophan metabolism on clear cell renal cell carcinoma, leading to the development of a tryptophan metabolism-related signature that may provide insights into patient prognosis, tumor biological status, and personalized treatment strategies. This signature serves as a valuable reference for further exploring the role of tryptophan metabolism in renal cell carcinoma and for the development of clinical applications based on this metabolic pathway.

Nrf2 Signaling in Renal Cell Carcinoma: A Potential Candidate for the Development of Novel Therapeutic Strategies

Renal cell carcinoma (RCC) is the most common type of kidney cancer arising from renal tubular epithelial cells and is characterized by a high aggressive behavior and invasiveness that lead to poor prognosis and high mortality rate. Diagnosis of RCC is generally incidental and occurs when the stage is advanced and the disease is already metastatic. The management of RCC is further complicated by an intrinsic resistance of this malignancy to chemotherapy and radiotherapy, which aggravates the prognosis. For these reasons, there is intense research focused on identifying novel biomarkers which may be useful for a better prognostic assessment, as well as molecular markers which could be utilized for targeted therapy. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcriptional factor that has been identified as a key modulator of oxidative stress response, and its overexpression is considered a negative prognostic feature in several types of cancers including RCC, since it is involved in various key cancer-promoting functions such as proliferation, anabolic metabolism and resistance to chemotherapy. Given the key role of Nrf2 in promoting tumor progression, this enzyme could be a promising biomarker for a more accurate prediction of RCC course and it can also represent a valuable therapeutic target. In this review, we provide a comprehensive literature analysis of studies that have explored the role of Nrf2 in RCC, underlining the possible implications for targeted therapy.

ARID2 Deficiency Enhances Tumor Progression via ERBB3 Signaling in TFE3-Rearranged Renal Cell Carcinoma

TFE3-rearranged Renal Cell Carcinoma (TFE3-RCC) is an aggressive subtype of RCC characterized by Xp11.2 rearrangement, leading to TFE3 fusion proteins with oncogenic potential. Despite advances in understanding its molecular biology, effective therapies for advanced cases remain elusive. This study investigates the role of ARID2, a component of the SWI/SNF chromatin remodeling complex, in TFE3-RCC. Through a series of in vitro and in vivo experiments, we confirmed that ARID2 acts as a tumor suppressor in TFE3-RCC. ARID2 knockout (KO) enhanced TFE3-RCC cell migration, proliferation, and tumor growth. Transcriptomic analysis revealed ERBB3 as a key target gene regulated by both PRCC-TFE3 and ARID2. Chromatin immunoprecipitation (ChIP) assays demonstrated that PRCC-TFE3 directly binds to and upregulates ERBB3 expression, with ARID2 KO further enhancing this effect. TFE3-RCC ARID2 KO cells exhibited significant gene expression enrichment in MAPK and ERBB3 signaling pathways. These cells also showed increased activation of ERBB3, EGFR, and selective activation of SRC and MAPK. TFE3-RCC ARID2 KO cells demonstrated heightened sensitivity to the ERBB3 inhibitor AZD8931 compared to their wild-type counterparts, exhibiting significantly reduced migration and proliferation rates. These findings suggest that the PRCC-TFE3-ARID2-ERBB3 axis plays a critical role in TFE3-RCC pathogenesis and highlights the potential of targeting ERBB3 in ARID2-deficient TFE3-RCC as a therapeutic strategy. This study provides new insights into the molecular mechanisms of TFE3-RCC and suggests avenues for precision treatment of this aggressive cancer.

TAF1D promotes tumorigenesis and metastasis by activating PI3K/AKT/mTOR signaling in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is a malignant tumor needs more effective treatments. TATA box-binding protein-associated factor RNA polymerase I subunit D (TAF1D) is a member of the selective factor 1 complex and functions in RNA polymerase I-dependent transcription. Higher TAF1D expression was found in ccRCC tumor tissues and indicated worse survival. Our study aimed to investigate the therapeutic potential of TAF1D in ccRCC. The proliferation and migration of ccRCC cells were significantly inhibited after TAF1D knockdown, while TAF1D overexpressing had opposite effects. Moreover, TAF1D knockdown induced cells to undergo G0/G1 cell cycle arrest and blockade of the epithelial-mesenchymal transition (EMT) process. Mechanistically, TAF1D affect the cell cycle and EMT through the PI3K/AKT/mTOR signaling pathway, thereby promoting the proliferation and metastasis of ccRCC cells in vivo and in vitro. The inhibitory effect of TAF1D knockdown could be reverted by the AKT activator SC79 in ccRCC cells, confirming this mechanism. Besides, TAF1D knockdown in ccRCC cells had a sensitizing effect on sunitinib and enhanced tumor cell inhibiting induced by sunitinib. In conclusion, TAF1D may be a promising target for the treatment of ccRCC and for overcoming sunitinib resistance.

Integrated Analysis of Single-Cell and Bulk RNA Sequencing Reveals HSD3B7 as a Prognostic Biomarker and Potential Therapeutic Target in ccRCC

Clear cell renal cell carcinoma (ccRCC) is the most common kidney malignancy, with a poor prognosis for advanced-stage patients. Identifying key biomarkers involved in tumor progression is crucial for improving treatment outcomes. In this study, we employed an integrated approach combining single-cell RNA sequencing (scRNA-seq) and bulk RNA sequencing (bulk RNA-seq) to identify biomarkers associated with ccRCC progression and prognosis. Single-cell transcriptomic data were obtained from publicly available datasets, and genes related to tumor progression were screened using Monocle2. Bulk RNA-seq data for ccRCC were retrieved from The Cancer Genome Atlas (TCGA) and integrated with scRNA-seq data to explore tumor heterogeneity. We identified 3 beta-hydroxy steroid dehydrogenase type 7 (HSD3B7) as a candidate biomarker for ccRCC, associated with poor overall survival, disease-specific survival, and progression-free interval. Elevated HSD3B7 expression correlated with aggressive clinical features such as advanced TNM stages, histologic grades, and metastasis. Functional studies demonstrated that HSD3B7 promotes cell proliferation, migration, and invasion in vitro, while its silencing significantly inhibits tumor growth in vivo. Our findings reveal that HSD3B7 is a novel biomarker for ccRCC, providing insights into its role in tumor progression and potential as a target for therapy. This study highlights the value of integrating scRNA-seq and bulk RNA-seq data to uncover key regulators of tumor biology and lays the foundation for developing personalized therapeutic strategies for ccRCC patients.

Randomized phase II dose comparison LITESPARK-013 study of belzutifan in patients with advanced clear cell renal cell carcinoma

BACKGROUND

Belzutifan is a first-in-class hypoxia-inducible factor subunit 2α (HIF-2α) inhibitor approved at a dose of 120 mg once daily for certain adults with VHL disease and adults with advanced renal cell carcinoma (RCC) following therapy with a programmed cell death protein 1 (PD-1) [or programmed death ligand 1 (PD-L1)] inhibitor and a vascular endothelial growth factor tyrosine kinase inhibitor. However, whether the belzutifan dose could be optimized is unclear.

PATIENTS AND METHODS

The phase II LITESPARK-013 study (NCT04489771) enrolled patients with advanced clear cell RCC whose disease progressed after one to three prior systemic therapies, including an anti-PD-(L)1 regimen. Patients were randomly assigned 1 : 1 to receive belzutifan 120 or 200 mg once daily. The primary endpoint was the objective response rate (ORR) per RECIST version 1.1. The secondary endpoints were duration of response (DOR), progression-free survival (PFS), overall survival (OS), and safety.

RESULTS

Overall, 154 patients were enrolled (120 mg: n = 76; 200 mg: n = 78). The median follow-up was 20.1 months (range 14.8-28.4). The ORR was 23.7% versus 23.1% for the 120 mg and 200 mg groups, respectively [P = 0.5312; -0.5%, 95% confidence interval (CI) -14.0% to 12.9%]. The median DOR was not reached for the 120 mg arm and was 16.1 months (2.1+ to 23.5+) for the 200 mg arm. No between-group differences were observed for PFS [hazard ratio (HR) 0.94, 95% CI 0.63-1.40] or OS (medians not reached; HR 1.11, 95% CI 0.65-1.90). Grade 3 or 4 treatment-related adverse events were observed in 35 patients (46.1%) in the 120 mg group and 36 patients (46.2%) in the 200 mg group.

CONCLUSIONS

The efficacy of belzutifan was similar between the 120 mg dose and the 200 mg dose for previously treated clear cell RCC. Safety at both doses was consistent with the known safety profile of belzutifan. These results further support 120 mg once daily as the preferred dose for belzutifan.

HAGLR, A Long Non-coding RNA of Potential Tumor Suppressive Function in Clear Cell Renal Cell Carcinoma: Diagnostic and Prognostic Implications

Research works suggested the role of long non-coding RNAs (lncRNAs) in pathogenesis of clear cell renal cell carcinoma (ccRCC). lncRNA HAGLR is studied in several malignancies, but not in ccRCC. From The Cancer Genome Atlas Kidney Renal Clear Cell Carcinoma (TCGA-KIRC) dataset, we analyzed molecular alterations of HAGLR and constructed a competitive endogenous RNA (ceRNA) network with related miRNAs and mRNAs. Gene Ontology analysis was done to identify important pathways enriched with HAGLR recovered mRNAs. Clinical importance of HAGLR and related mRNAs was assessed and, the impact of selected mRNA-encoding genes on tumor immune infiltration was studied using TIMER. HAGLR expression was reduced in ccRCC than in normal kidneys, and correlated significantly with gene promoter methylation. Low HAGLR level in tumors showed diagnostic potency, and was associated with clinicopathological parameters (stage/grade/metastasis) and poor patient survival. The HAGLR-associated ceRNA network constituted 13 miRNAs and 23 mRNAs differentially expressed in the TCGA-KIRC dataset. From HAGLR recovered mRNA-encoding genes, we developed a 5-gene (PAQR5, ARHGAP24, HABP4, PDLIM5, and RPS6KA2) prognostic signature in the training dataset and validated it in testing as well as entire datasets. The expression level of signature genes showed negative correlation with tumor infiltration of immune cells having adverse impact on ccRCC prognosis and also with tumor derived chemokines facilitating the infiltration. In conclusion, HAGLR seemed to play a tumor suppressive role in ccRCC. HAGLR and associated gene signature may have implementation in improving existing prognostic measure and developing effective immunotherapeutic strategies for ccRCC.

LINC01322 may serve as a potential diagnostic marker for advanced stage tumors in renal cell carcinoma patients eligible for total nephrectomy

Background

Renal cell carcinoma (RCC) is a common urological cancer globally and shows a favorable prognosis in early stages of the tumor progression. Due to the poor prognosis for metastatic RCC patients, it is crucial to explore the molecular biology of RCC progression to establish efficient diagnostic and therapeutic markers for these patients. Long non-coding RNAs (lncRNAs) have critical roles in regulation of tumor cell proliferation, migration, and apoptosis during RCC progression. For the first time in the present study, we assessed the LINC01322 RNA expression levels in RCC patients to introduce that as a potential tumor marker among these patients.

Methods

we visualized LINC01322 expression data using the online tool Gene Expression Profiling Interactive Analysis (GEPIA2) across different cancers and normal tissues. Fifty fresh samples of RCC tumor tissues and their adjacent normal margins were collected to analyze the RNA expression of LINC01322 and its association with the clinicopathological features of RCC patients. The SYBR green method was used in real-time PCR to measure the LINC01322 RNA expression levels in RCC patients.

Results

Based on in-silico analysis, we hypothesized that LINC01322 could be involved in RCC progression by interacting with VHL, thereby influencing the tumor microenvironment. There were significant increased levels of LINC01322 RNA expressions in advanced stage compared with primary stage tumors that were located in left kidney (p = 0.048). Left kidney that were undergone the total nephrectomy had significant higher levels of LINC01322 RNA expressions compared with tumors in right kidney (p = 0.045). There was a direct correlation between the levels of LINC01322 RNA expression and RCC tumor size.

Conclusions

considering the substantial increase in LINC01322 RNA expression in advanced stage RCC tumors that are candidates for total nephrectomy; it could be suggested as a potential diagnostic indicator for high-risk patients. In-silico analysis also revealed that LINC01322 could be involved in regulation of tumor microenvironment during RCC progression by interacting with VHL. However, further investigations are needed to validate the potential link between LINC01322 and VHL during RCC progression. Evaluating the serum LINC01322 RNA levels in RCC patients is also necessary to use that as a diagnostic marker in clinical settings.

Transcriptome-based network analysis related to regulatory T cells infiltration identified RCN1 as a potential biomarker for prognosis in clear cell renal cell carcinoma

BACKGROUND

Regulatory T cells (Tregs) play a critical role in shaping the immunosuppressive microenvironment within tumors. Investigating the role of Tregs in Clear cell renal cell carcinoma (ccRCC) is crucial for identifying prognostic markers and therapeutic targets for ccRCC.

METHODS

Weighted gene co-expression network analysis (WGCNA) was utilized to pinpoint modules related to Treg infiltration in TCGA-KIRC samples. Following this, consensus clustering was employed to derive two clusters associated with Treg infiltration in ccRCC. A prognostic model was then developed using the gene module associated with Treg infiltration. We then evaluated the ability of the prognostic model to predict ccRCC overall survival and demonstrated that RCN1 can be used as a target to predict ccRCC prognosis.

RESULTS

We deduce that the two clusters associated with Treg infiltration exhibit distinct compositions of the immune microenvironment, pathway activations, prognosis, and drug sensitivities commonly utilized in ccRCC treatment. Furthermore, a 7-gene model risk score, developed based on ccRCC Treg infiltration, proved to be a reliable prognostic marker in both training and validation cohorts. Additionally, survival analysis indicated that RCN1 serves as a reliable prognostic factor for ccRCC. Single-cell sequencing analysis revealed that RCN1 is predominantly expressed in tumor cells. A pan-cancer analysis highlighted that RCN1 is linked with poor prognosis and the activation of inflammatory response pathways across various cancers.

CONCLUSION

We developed a prognostic model associated with Treg infiltration, which facilitates the clinical categorization of ccRCC progression. Moreover, our findings underscore the significant potential of RCN1 as a ccRCC biomarker.

ZBTB7A forms a heterodimer with ZBTB2 and inhibits ZBTB2 homodimerization required for full activation of HIF-1

Hypoxia-inducible factor 1 (HIF-1), recognized as a master transcription factor for adaptation to hypoxia, is associated with malignant characteristics and therapy resistance in cancers. It has become clear that cofactors such as ZBTB2 are critical for the full activation of HIF-1; however, the mechanisms downregulating the ZBTB2-HIF-1 axis remain poorly understood. In this study, we identified ZBTB7A as a negative regulator of ZBTB2 by analyzing protein sequences and structures. We found that ZBTB7A forms a heterodimer with ZBTB2, inhibits ZBTB2 homodimerization necessary for the full expression of ZBTB2-HIF-1 downstream genes, and ultimately delays the proliferation of cancer cells under hypoxic conditions. The Cancer Genome Atlas (TCGA) analyses revealed that overall survival is better in patients with high ZBTB7A expression in their tumor tissues. These findings highlight the potential of targeting the ZBTB7A-ZBTB2 interaction as a novel therapeutic strategy to inhibit HIF-1 activity and improve treatment outcomes in hypoxia-related cancers.

Oral Hypoxia-Inducible Factor 2α Inhibitor Belzutifan in Ocular von Hippel-Lindau Disease: Subgroup Analysis of the Single-Arm Phase 2 LITESPARK-004 Study

PURPOSE

To report the efficacy of the oral hypoxia-inducible factor 2α inhibitor belzutifan in participants with von Hippel-Lindau disease-associated retinal hemangioblastomas in the LITESPARK-004 study.

DESIGN

Subgroup analysis of the phase 2, single-arm, open-label LITESPARK-004 study.

PARTICIPANTS

Adults with 1 or more von Hippel-Lindau disease-associated measurable renal cell carcinoma tumors not requiring immediate surgical intervention were eligible.

METHODS

Participants received oral belzutifan 120 mg once daily until disease progression or unacceptable treatment-related toxicity.

MAIN OUTCOME MEASURES

Efficacy of belzutifan in retinal hemangioblastomas was a secondary end point, measured as response (improved, stable, or progressed) by independent reading center-certified graders based on color fundus imaging performed every 12 weeks using the investigator's preferred imaging standards. Additional assessments, where available, included OCT and ultra-widefield fluorescein angiography.

RESULTS

Among 61 participants in LITESPARK-004, 12 had 1 or more evaluable active retinal hemangioblastomas in 16 eyes at baseline per independent reading center. As of April 1, 2022, the median follow-up for participants with ocular von Hippel-Lindau disease at baseline was 37.3 months. All 16 eyes were graded as improved, with a response rate of 100.0% (95% confidence interval, 79.4%-100%). No new retinal hemangioblastomas or ocular disease progression were reported as of data cutoff date. Eight participants underwent additional multimodal eye assessments performed at the National Institutes of Health study site. Among this subgroup, 10 of 24 hemangioblastomas in 8 eyes of 6 participants measured 500 μm or more in greatest linear dimension at baseline and were analyzed further. All 10 hemangioblastomas had a mean area reduction of 15% or more by month 12 and of 30% or more by month 24.

CONCLUSIONS

Belzutifan showed promising activity against ocular von Hippel-Lindau disease, including capacity to control retinal hemangioblastomas, with effects sustained for more than 2 years while treatment is ongoing.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Von Hippel-Lindau protein signalling in clear cell renal cell carcinoma

The distinct pathological and molecular features of kidney cancer in adaptation to oxygen homeostasis render this malignancy an attractive model for investigating hypoxia signalling and potentially developing potent targeted therapies. Hypoxia signalling has a pivotal role in kidney cancer, particularly within the most prevalent subtype, known as renal cell carcinoma (RCC). Hypoxia promotes various crucial pathological processes, such as hypoxia-inducible factor (HIF) activation, angiogenesis, proliferation, metabolic reprogramming and drug resistance, all of which contribute to kidney cancer development, growth or metastasis formation. A substantial portion of kidney cancers, in particular clear cell RCC (ccRCC), are characterized by a loss of function of Von Hippel-Lindau tumour suppressor (VHL), leading to the accumulation of HIF proteins, especially HIF2α, a crucial driver of ccRCC. Thus, therapeutic strategies targeting pVHL-HIF signalling have been explored in ccRCC, culminating in the successful development of HIF2α-specific antagonists such as belzutifan (PT2977), an FDA-approved drug to treat VHL-associated diseases including advanced-stage ccRCC. An increased understanding of hypoxia signalling in kidney cancer came from the discovery of novel VHL protein (pVHL) targets, and mechanisms of synthetic lethality with VHL mutations. These breakthroughs can pave the way for the development of innovative and potent combination therapies in kidney cancer.

Prognostic Impact and Genomic Backgrounds of Renal Parenchymal Infiltration or Micronodular Spread in Nonmetastatic Clear Cell Renal Cell Carcinoma

A subset of clear cell renal cell carcinomas (ccRCCs) exhibits various growth patterns that infiltrate the normal renal parenchyma; however, our understanding of its association with cancer aggressiveness is incomplete. Here, we show that the morphology of the tumor interface with normal renal parenchyma is robustly associated with cancer recurrence after surgery, even when compared with the TNM staging system or the World Health Organization/International Society of Urological Pathology (WHO/ISUP) nuclear grade in nonmetastatic ccRCC. Hematoxylin and eosin-stained slides of whole tissue sections from surgical specimens were analyzed using a cohort of 331 patients with nonmetastatic ccRCC treated with radical nephrectomy. The patients were classified into 10 subgroups based on our classification algorithms for assessing the tumor interface with normal renal parenchyma. Among the 10 subgroups, 4 subgroups consisting of 40 patients (12%) were identified to have aggressive forms of nonmetastatic ccRCC associated with poor prognosis and unified as renal parenchymal infiltration or micronodular spread (RPI/MNS) phenotypes. Multivariable analyses showed that RPI/MNS phenotypes were robustly associated with shorter disease-free survival, independently of existing pathological factors including the TNM staging system and WHO/ISUP nuclear grade. The hazard ratio was highest for RPI/MNS (4.62), followed by WHO/ISUP grades 3 to 4 (2.11) and ≥pT3a stage (2.05). In addition, we conducted genomic analyses using next-generation sequencing of infiltrative lesions in 18 patients with RPI/MNS and tumor lesions in 33 patients without RPI/MNS. Results showed that alterations in SETD2 and TSC1 might be associated with RPI/MNS phenotypes, whereas alterations in PBRM1 might be associated with non-RPI/MNS phenotypes. These data suggest that RPI/MNS may be associated with aggressive genomic backgrounds of ccRCC, although more comprehensive analyses with a larger sample size are required. Future studies may further elucidate the clinical implications of RPI/MNS, particularly for deciding the indication of adjuvant treatment after nephrectomy.