Checkpoint Inhibitors for the Treatment of Renal Cell Carcinoma

GLUT5-overexpression-related tumorigenic implications

Glucose transporter 5 (GLUT5) overexpression has gained increasing attention due to its profound implications for tumorigenesis. This manuscript provides a comprehensive overview of the key findings and implications associated with GLUT5 overexpression in cancer. GLUT5 has been found to be upregulated in various cancer types, leading to alterations in fructose metabolism and enhanced glycolysis, even in the presence of oxygen, a hallmark of cancer cells. This metabolic shift provides cancer cells with an alternative energy source and contributes to their uncontrolled growth and survival. Beyond its metabolic roles, recent research has unveiled additional aspects of GLUT5 in cancer biology. GLUT5 overexpression appears to play a critical role in immune evasion mechanisms, which further worsens tumor progression and complicates therapeutic interventions. This dual role of GLUT5 in both metabolic reprogramming and immune modulation highlights its significance as a potential diagnostic marker and therapeutic target. Understanding the molecular mechanisms driving GLUT5 overexpression is crucial for developing targeted therapeutic strategies that can disrupt the unique vulnerabilities of GLUT5-overexpressing cancer cells. This review emphasizes the complexities surrounding GLUT5's involvement in cancer and underscores the pressing need for continued research to unlock its potential as a diagnostic biomarker and therapeutic target, ultimately improving cancer management and patient outcomes.

A Rare Case of Giant Cell Arteritis After the Administration of Checkpoint Inhibitor Therapy in a Metastatic Renal Cell Carcinoma Patient

We present a rare case of metastatic renal cell carcinoma in a patient who developed giant cell arteritis (GCA) after the administration of checkpoint inhibitor therapy with nivolumab and ipilimumab. The patient was initially treated with a combination of nivolumab and ipilimumab, showing a near-complete response with minimal side effects. However, after several cycles of checkpoint inhibitor therapy, the patient developed symptoms consistent with GCA, leading to a halt in the immunotherapy. This report highlights the complexity of managing the adverse effects of immunotherapeutic agents and the importance of a multidisciplinary approach in the management of complications such as GCA.

Assessments of tumor mutational burden estimation by targeted panel sequencing: A comprehensive simulation analysis

Tumor mutational burden (TMB), when at a high level, is an emerging indicative factor of sensitivity to immune checkpoint inhibitors. Previous studies have shown that the more affordable and accurate targeted panels can be used to measure TMB as a substitute for whole exome sequencing (WES). However, additional processes, such as hotspot mutations exclusion and TMB adjustment, are usually required to deal with the effect of the limited panel sizes. A comprehensive investigation of the effective factors is needed for accurate TMB estimation by targeted panels. In this study, we quantitatively evaluated the variances of TMB values calculated by WES and targeted panels using 10,000 simulated targeted panels with panel sizes ranging from 0.2 to 3.1 million bases. With The Cancer Genome Atlas (TCGA) cancer samples and mutation profiles, we fixed regressions on WES-TMBs and panel-TMBs to assess the performance of a given targeted panel. Panel size was found as one of the major effective factors of TMB estimation. Meanwhile, by investigating the well-performing small panels that reported TMB values similar to those of WES, we demonstrated the evidence of the cancer type-specific impacts of genes on TMB estimation and identified high-impact gene sets for different cancer types based on the TCGA data. This study revealed the quantitative correlations between TMB variance and panel size, and the potential impacts of individual genes on TMB estimation. Our results suggested that for cancer patients diagnosed using targeted panels, it would be highly beneficial to have the capability to directly measure TMB from the targeted sequencing data. This would greatly assist in making decisions regarding the use of immunotherapies.

Unveiling the multi-target compounds of Rhazya stricta: Discovery and inhibition of novel target genes for the treatment of clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is a prevalent kidney malignancy with a pressing need for innovative therapeutic strategies. In this context, emerging research has focused on exploring the medicinal potential of plants such as Rhazya stricta. Nevertheless, the complex molecular mechanisms underlying its potential therapeutic efficacy remain largely elusive. Our study employed an integrative approach comprising data mining,network pharmacology,tissue cell type analysis, and molecular modelling approaches to identify potent phytochemicals from R. stricta, with potential relevance for ccRCC treatments. Initially, we collected data on R. stricta's phytochemical from public databases. Subsequently, we integrated this information with differentially expressed genes (DEGs) in ccRCC, which were derived from microarray datasets(GSE16441,GSE66270, and GSE76351). We identified potential intersections between R. stricta and ccRCC targets, which enabled us to construct a compound-genes-pathway network using Cytoscape software. This helped illuminate R. stricta's multi-target pharmacological effects on ccRCC. Moreover, tissue cell type analysis added another layer of insight into the cellular specificity of potential therapeutic targets in the kidney. Through further Kaplan-Meier survival analysis, we pinpointed MMP9,ACE,ERBB2, and HSP90AA1 as prospective diagnostic and prognostic biomarkers for ccRCC. Notably, our study underscores the potential of R. stricta derived compounds-namely quebrachamine,corynan-17-ol, stemmadenine,strictanol,rhazinilam, and rhazimolare-to impede ccRCC progression by modulating the activity of MMP9,ACE,ERBB2, and HSP90AA1 genes. Further, molecular docking and dynamic simulations confirmed the plausible binding affinities of these compounds. Despite these promising findings, we recognize the need for comprehensive in vivo and in vitro studies to further investigate the pharmacokinetics and biosafety profiles of these compounds.

Chemotherapeutics and CAR-T Cell-Based Immunotherapeutics Screening on a 3D Bioprinted Vascularized Breast Tumor Model

Despite substantial advancements in development of cancer treatments, lack of standardized and physiologically-relevant in vitro testing platforms limit the early screening of anticancer agents. A major barrier is the complex interplay between the tumor microenvironment and immune response. To tackle this, a dynamic-flow based 3D bioprinted multi-scale vascularized breast tumor model, responding to chemo and immunotherapeutics is developed. Heterotypic tumors are precisely bioprinted at pre-defined distances from a perfused vasculature, exhibit tumor angiogenesis and cancer cell invasion into the perfused vasculature. Bioprinted tumors treated with varying dosages of doxorubicin for 72 h portray a dose-dependent drug response behavior. More importantly, a cell based immune therapy approach is explored by perfusing HER2-targeting chimeric antigen receptor (CAR) modified CD8+ T cells for 24 or 72 h. Extensive CAR-T cell recruitment to the endothelium, substantial T cell activation and infiltration to the tumor site, resulted in up to ≈70% reduction in tumor volumes. The presented platform paves the way for a robust, precisely fabricated, and physiologically-relevant tumor model for future translation of anti-cancer therapies to personalized medicine.

Metastatic Immune-Related Genes for Affecting Prognosis and Immune Response in Renal Clear Cell Carcinoma

Background: In renal clear cell carcinoma, a common cancer of the urinary system, 25–30% patients are metastatic at initial diagnosis and 20–30% patients have a tendency of recurrence and metastasis after local surgery. With the rapid development of tumor immunology, immune agents have brought new directions to tumor therapy. However, no relevant studies have explored the role of immune-related genes in kidney cancer metastasis.

Methods: Co-expressed metastatic immune-related differentially expressed genes (mIR-DEGs) were screened by GSE12606, GSE47352, and immunorelated genes. Then, differential expression analysis, prognostic analysis, and univariate and multivariate Cox regression analysis in KIRC were performed to determine independent prognostic factors associated, and the risk prognostic model was established. The correlation of hub mIR-DEGs with clinicopathological factors, immune invasion, and immune checkpoints was analyzed, and the expression of hub mIR-DEGs and their effect on tumor were re-evaluated by OCLR scores in KIRC.

Results: By comprehensive bioassay, we found that FGF17, PRKCG, SSTR1, and SCTR were mIR-DEGs with independent prognostic values, which were significantly associated with clinicopathological factors and immune checkpoint–related genes. The risk prognostics model built on this basis had good predictive potential. In addition, targeted small molecule drugs, including calmidazolium and sulfasalazine, were predicted for mIR-DEGs. Further experimental results were consistent with the bioinformatics analysis.

Conclusion: This study preliminarily confirmed that FGF17, PRKCG, SSTR1, and SCTR were targeted genes affecting renal cancer metastasis and related immune responses and can be used as potential therapeutic targets and prognostic biomarkers for renal cancer. Preliminary validation found that PRKCG and SSTR1 were consistent with predictions.

Identification of a Novel Epithelial-Mesenchymal Transition-Related Gene Signature for Endometrial Carcinoma Prognosis

(1) Background: Endometrial cancer is the most prevalent cause of gynecological malignant tumor worldwide. The prognosis of endometrial carcinoma patients with distant metastasis is poor. (2) Method: The RNA-Seq expression profile and corresponding clinical data were downloaded from the Cancer Genome Atlas database and the Gene Expression Omnibus databases. To predict patients’ overall survival, a 9 EMT-related genes prognosis risk model was built by machine learning algorithm and multivariate Cox regression. Expressions of nine genes were verified by RT-qPCR. Responses to immune checkpoint blockades therapy and drug sensitivity were separately evaluated in different group of patients with the risk model. (3) Endometrial carcinoma patients were assigned to the high- and low-risk groups according to the signature, and poorer overall survival and disease-free survival were showed in the high-risk group. This EMT-related gene signature was also significantly correlated with tumor purity and immune cell infiltration. In addition, eight chemical compounds, which may benefit the high-risk group, were screened out. (4) Conclusions: We identified a novel EMT-related gene signature for predicting the prognosis of EC patients. Our findings provide potential therapeutic targets and compounds for personalized treatment. This may facilitate decision making during endometrial carcinoma treatment.

Identification of a Novel Defined Immune-Autophagy-Related Gene Signature Associated With Clinical and Prognostic Features of Kidney Renal Clear Cell Carcinoma

Background: As a common cancer of the urinary system in adults, renal clear cell carcinoma is metastatic in 30% of patients, and 1-2 years after diagnosis, 60% of patients die. At present, the rapid development of tumor immunology and autophagy had brought new directions to the treatment of renal cancer. Therefore, it was extremely urgent to find potential targets and prognostic biomarkers for immunotherapy combined with autophagy. Methods: Through GSE168845, immune-related genes, autophagy-related genes, and immune-autophagy-related differentially expressed genes (IAR-DEGs) were identified. Independent prognostic value of IAR-DEGs was determined by differential expression analysis, prognostic analysis, and univariate and multivariate Cox regression analyses. Then, the lasso Cox regression model was established to evaluate the correlation of IAR-DEGs with the immune score, immune checkpoint, iron death, methylation, and one-class logistic regression (OCLR) score. Results: In this study, it was found that CANX, BID, NAMPT, and BIRC5 were immune-autophagy-related genes with independent prognostic value, and the risk prognostic model based on them was well constructed. Further analysis showed that CANX, BID, NAMPT, and BIRC5 were significantly correlated with the immune score, immune checkpoint, iron death, methylation, and OCLR score. Further experimental results were consistent with the bioinformatics analysis. Conclusion: CANX, BID, NAMPT, and BIRC5 were potential targets and effective prognostic biomarkers for immunotherapy combined with autophagy in kidney renal clear cell carcinoma.

Clinicopathological and Preclinical Patient-Derived Model Studies Define High Expression of NRN1 as a Diagnostic and Therapeutic Target for Clear Cell Renal Cell Carcinoma

Background

Acquired therapeutic resistance and metastasis/recurrence remain significant challenge in advance renal cell carcinoma (RCC), thus the establishment of patient-derived cancer models may provide a clue to assess the problem. We recently characterized that neuritogenesis-related protein neuritin 1 (NRN1) functions as an oncogene in testicular germ cell tumor. This study aims to elucidate the role of NRN1 in RCC.

Methods

NRN1 expression in clinical RCC specimens was analyzed based on immunohistochemistry. NRN1-associated genes in RCC were screened by the RNA-sequencing dataset from The Cancer Genome Atlas (TCGA). RCC patient-derived cancer cell (RCC-PDC) spheroid cultures were established and their viabilities were evaluated under the condition of gene silencing/overexpression. The therapeutic effect of NRN1-specific siRNA was evaluated in RCC-PDC xenograft models.

Results

NRN1 immunoreactivity was positively associated with shorter overall survival in RCC patients. In TCGA RCC RNA-sequencing dataset, C-X-C chemokine receptor type 4 (CXCR4), a prognostic and stemness-related factor in RCC, is a gene whose expression is substantially correlated with NRN1 expression. Gain- and loss-of-function studies in RCC-PDC spheroid cultures revealed that NRN1 significantly promotes cell viability along with the upregulation of CXCR4. The NRN1-specific siRNA injection significantly suppressed the proliferation of RCC-PDC-derived xenograft tumors, in which CXCR4 expression is significantly repressed.

Conclusion

NRN1 can be a potential diagnostic and therapeutic target in RCC as analyzed by preclinical patient-derived cancer models and clinicopathological studies.

Pseudogene HSPB1P1 contributes to renal cell carcinoma proliferation and metastasis by targeting miR-296-5p to regulate HMGA1 expression

With the aid of next-generation sequencing technology, pseudogenes have been widely recognized as functional regulators in the development and progression of certain diseases, especially cancer. Our present study aimed to investigate the functions and molecular mechanisms of HSPB1-associated protein 1 pseudogene 1 (HSPB1P1) in renal cell carcinoma (RCC). HSPB1P1 expression at the mRNA levels was determined by quantitative real-time polymerase chain reaction, and its clinical significance was assessed. Cell viability was detected by Cell Counting Kit-8 assay. Cell migration and invasion were detected by transwell assays. The location of HSPB1P1 in RCC cells was detected by subcellular distribution analysis. The direct relationship between HSPB1P1 and miR-296-5p/HMGA1 axis was verified by dual-luciferase reporter assay and RNA immunoprecipitation assay. Our results identify the elevated expression of HSPB1P1 in RCC tissues and cell lines, which predicted advanced progression and poor prognosis in patients with RCC. Knockdown of HSPB1P1 suppressed cell proliferation, migration, and invasion, and reversed epithelial-mesenchymal transition process in RCC. HSPB1P1 was mostly enriched in the cytoplasm and functioned as a miRNA sponge for miR-296-5p and then regulated high-mobility group A1 expression. In conclusion, our study indicated that HSPB1P1 contributed to RCC progression by targeting the miR-296-5p/HMGA1 axis, and should be considered as a promising biomarker and therapeutic target for clinical applications.

Immunotherapy for metastatic renal cell carcinoma: A brief history, current trends, and future directions

Recent innovations in systemic therapy for metastatic renal cell carcinoma (mRCC) have occurred at a break-neck pace. In the 1980s, nontargeted cytokine-mediated immunotherapy was the systemic therapy of choice. Based on improvements in tolerability and patient outcomes, targeted antiangiogenic agents supplanted cytokines in the early 2000s. During the last decade, the most recent innovation has come in the form of immune-checkpoint inhibitors (ICIs), a form of immunotherapy that enhances immune-mediated tumor cell destruction. ICIs improve on all prior iterations of systemic therapies and have become the first-line therapy for many mRCC indications. ICIs have been shown to increase overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and complete response rate (CRR) in mRCC patients. We reviewed the recent trends associated with ICI management of mRCC, their immune-related adverse events, and cost implications.

Metastatic Renal Cell Carcinoma to the Spine: Outcomes and Morbidity: Single-Center Experience

BACKGROUND

Renal cell carcinoma with metastases to the spine (RCCMS) requires a multidisciplinary approach. We reviewed our institutional experience with RCCMS patients undergoing spinal surgery in order to identify factors that may affect clinical outcomes, survival, and complications.

METHODS

Patients with RCCMS who underwent operative intervention from 2007 to 2020 were reviewed retrospectively.

RESULTS

Forty-four patients with the diagnosis of RCCMS were identified. Pain was the most common symptom, and neurologic dysfunction was present in one third of cases. Thoracic spine was the most common location (N = 27), followed by the lumbar (N = 12) and cervical (N = 5) regions. The overall survival from diagnosis of renal cell carcinoma was 25 (2 - 194) months and 8 (0.3 - 92) months after spinal surgery. Gender, age, spinal level, postoperative radiation, and nephrectomy had no bearing on survival. Survival for patients with a Tokuhashi score of 0 - 8, 9 - 11, and 12 - 15 was 6.5 (1.5 - 23.5), 8.9 (0.3 - 91.6), and 23.4 (2.5 - 66) months, respectively (P = 0.03). The postoperative American Spinal Cord Injury Association score of E (hazard ratio 0.109 [95% confidence interval 0.022 - 0.534, P = 0.006) also bore a significant influence on survival. There was a total of 10 complications in 7 of 44 (16%) patients.

CONCLUSIONS

Median postoperative survival of patients with RCCMS was 8 (0.3 - 92) months. Higher Tokuhashi score and ASIA E score at follow-up correlated with improved overall survival. Complication rate was 16%. Spinal surgery in RCCMS is indicated for the preservation of function and prevention of neurologic deterioration. Multimodality therapy with improved chemotherapy and stereotactic spinal radiation is expected to impact quality and length of survival positively.

Functional inhibition of cancer stemness-related protein DPP4 rescues tyrosine kinase inhibitor resistance in renal cell carcinoma

Tyrosine kinase inhibitors (TKIs) are used as targeted drugs for advanced renal cell carcinoma (RCC), although most cases eventually progress by acquiring resistance. Cancer stemness plays critical roles in tumor aggressiveness and therapeutic resistance, and dipeptidyl peptidase IV (DPP4) has been recently identified as a cancer stemness-related protein. A question arises whether DPP4 contributes to TKI efficacy in RCC. We established patient-derived RCC spheroids and showed that DPP4 expression is associated with stemness-related gene expression. TKI sunitinib resistance was rescued by DPP4 inhibition using sitagliptin or specific siRNAs in RCC cells and tumors. DPP4 expression can be inducible by retinoic acid and repressed by ALDH1A inhibition. Among type 2 diabetes patients with clinical RCC tumors, higher TKI efficacy is observed in those bearing DPP4^high tumors treated with DPP4 inhibitors. This study provides new insights into TKI resistance and drug repositioning of DPP4 inhibitor as a promising strategy for advanced RCC.

An epithelial-mesenchymal transition-related long non-coding RNA signature to predict overall survival and immune microenvironment in kidney renal clear cell carcinoma

Kidney renal clear cell carcinoma (ccRCC) is a malignant tumor originating from renal tubular epithelium, lncRNAs can regulate the occurrence and development of EMT by targeting EMT transcription factors. We constructed a new survival signature based on EMT-related differentially expressed lncRNAs obtained from the Cancer Genome Atlas (TCGA-KIRC). We first determined 1377 EMT-related lncRNAs, lncRNA AL035661.1 with the largest correlation coefficient and the target gene was PFN2 (cor = 0.843; P= 1.37E-146). Meanwhile, we found an AUC of 0.758 in our signature and we predicted the AUC values of the patients’ 1, 2, 3-year survival rate as 0.768, 0.749, and 0.762 in TCGA cohort, respectively. Multivariate COX analysis was performed to determine if risk score was an independent prognostic predictor of OS. The results indicated that our risk score can be an independent predictor for OS (Univariate: HR = 1.350, 95% CI = 1.276–1.428, P< 0.001; Multivariate: HR = 1.295, 95% CI = 1.201–1.396, P< 0.001). We identified novel EMT-related lncRNAs markers for ccRCC prognosis. The underlying mechanism between EMT-related lncRNAs in ccRCC and tumor immunity is still unclear and requires further study.

Case series review of neuroradiologic changes associated with immune checkpoint inhibitor therapy

While immuno-oncotherapy (IO) has significantly improved outcomes in the treatment of systemic cancers, various neurological complications have accompanied these therapies. Treatment with immune checkpoint inhibitors (ICIs) risks multi-organ autoimmune inflammatory responses with gastrointestinal, dermatologic, and endocrine complications being the most common types of complications. Despite some evidence that these therapies are effective to treat central nervous system (CNS) tumors, there are a significant range of related neurological side effects due to ICIs. Neuroradiologic changes associated with ICIs are commonly misdiagnosed as progression and might limit treatment or otherwise impact patient care. Here, we provide a radiologic case series review restricted to neurological complications attributed to ICIs, anti-CTLA-4, and PD-L-1/PD-1 inhibitors. We report the first case series dedicated to the review of CNS/PNS radiologic changes secondary to ICI therapy in cancer patients. We provide a brief case synopsis with neuroimaging followed by an annotated review of the literature relevant to each case. We present a series of neuroradiological findings including nonspecific parenchymal and encephalitic, hypophyseal, neural (cranial and peripheral), meningeal, cavity-associated, and cranial osseous changes seen in association with the use of ICIs. Misdiagnosis of radiologic abnormalities secondary to neurological immune-related adverse events can impact patient treatment regimens and clinical outcomes. Rapid recognition of various neuroradiologic changes associated with ICI therapy can improve patient tolerance and adherence to cancer therapies.

Apolipoprotein C1 (APOC1): A Novel Diagnostic and Prognostic Biomarker for Clear Cell Renal Cell Carcinoma

Background: Apolipoprotein C1 (APOC1) has been proved to play a critical role in gastric, breast, lung, and pancreatic cancer. However, the relationship between APOC1 and urinary tumors remains unclear. This study aimed to assess the diagnostic and prognostic value of APOC1 in urinary tumors.

Methods: We performed a pan analysis of APOC1 mRNA expression in urinary cancer using the Gene Expression Profiling Interactive Analysis (GEPIA) database. To further investigate the prognostic value of APOC1 expression in urinary cancers, the Kaplan-Meier plotter database was used. Furthermore, we collected the tumor and adjacent normal samples of 32 ccRCC patients to perform qRT-PCR and western blotting assays. A total of 72 cases with ccRCC were analyzed using tissue microarrays (TMAs).

Results: Our results based on Kaplan-Meier plotter database indicated that a high expression of APOC1 may lead to poor overall survival (OS, p = 0.0019) in patients with ccRCC. Furthermore, the cancer stages and tumor grade of ccRCC appeared to be strongly linked with APOC1 expression according to UALCAN database. Hence, we reached a preliminary conclusion that APOC1 may play a key role in the tumorigenesis and progression of ccRCC. Furthermore, the Kaplan-Meier survival curve analyses of 72 clinical patients indicated that high expression of APOC1 was associated with poor progression-free survival (PFS, p = 0.007) and OS (p = 0.022). In addition, univariate Cox regression analysis confirmed the significant relationship between APOC1 expression and survival (p = 0.038). The TMAs analysis in combination with the patients' clinicopathological features was also performed. The expression of APOC1 was found to be significantly correlated with the tumor size (p = 0.018) and histological grade (p = 0.016).

Conclusions: In conclusion, the findings of our study suggest that APOC1 may serve as a novel diagnostic and prognostic biomarker for ccRCC. Further evidence on the mechanism of APOC1 promoting tumor progression may transform it to a new therapeutic target for the treatment of ccRCC.

Auranofin-Based Analogues Are Effective Against Clear Cell Renal Carcinoma In Vivo and Display No Significant Systemic Toxicity

Effective pharmacological treatments for patients with advanced clear cell renal carcinoma (ccRCC) are limited. Bimetallic titanium-gold containing compounds exhibit significant cytotoxicity against ccRCC in vitro and in vivo and inhibit invasion and angiogenisis in vitro and markers driving these phenomena. However, in vivo preclinical evaluations of such compounds have not examined their pharmacokinetics, pathology, and hematology. Here we use NOD.CB17-Prkdc SCID/J mice bearing xenograft ccRCC Caki-1 tumors to evaluate the in vivo efficacies of two titanium-gold compounds Titanocref and Titanofin (based on auranofin analogue scaffolds) accompanied by pharmacokinetic and pathology studies. A therapeutic trial was performed over 21 days at 5 mg/kg/72h of Titanocref and 10 mg/kg/72h of Titanofin tracking changes in tumor size. We observed a significant reduction of 51% and 60%, respectively (p < 0.01) in tumor size in the Titanocref- and Titanofin-treated mice compared to the starting size, while the vehicle-treated mice exhibited a tumor size increase of 138% (p < 0.01). Importantly, no signs of pathological complication as a result of treatment were found. In addition, Titanocref and Titanofin treatment reduced angiogenesis by 38% and 54%, respectively. Microarray and qRT-PCR analysis of ccRCC Caki-1 cells treated with Titanocref revealed that the compound alters apoptosis, JNK MAP kinase, and ROS pathways within 3 h of treatment. We further show activation of apoptosis by Titanocref and Titanofin in vivo by caspase 3 assay. Titanocref is active against additional kidney cancer cells. Titanocref and Titanofin are therefore promising candidates for further evaluation toward clinical application in the treatment of ccRCC.

Integrative bioinformatics analysis of a prognostic index and immunotherapeutic targets in renal cell carcinoma

Renal cell carcinoma (RCC) is one of the most common malignancies. The immunogenomic landscape signature significantly correlates with the progression and prognosis of RCC. Novel therapeutic targets and prognostic indices in RCC are highly desirable. The TCGA database enables comprehensive immunogenomic landscape analysis. Differentially expressed immune-related genes (IRGs) were obtained from TCGA and GO analyses, and KEGG pathway analyses were performed to explore their functions and molecular mechanisms. Multivariable Cox analysis was utilized to calculate the risk score of each patient and locate survival-associated IRGs, thereby constructing a novel immune-related gene-based prognostic index (IRGPI). The correlation between IRGPI and immune cell infiltration was also investigated. A total of 41 differentially expressed IRGs were notably related to prognosis in RCC. GO functions and KEGG pathway analyses demonstrated that these genes were primarily associated with the tumour immune response and cytokine-cytokine receptor interaction pathway. An IRGPI based on seventeen survival-associated differentially expressed IRGs was constructed and exhibited a moderate predictive value in the prognosis of RCC patients and a powerful identification ability in refining the risk stratification of RCC patients. A close correlation was found between IRGPI and specific clinicopathological parameters, including age, gender, pathological stage, tumour stage, lymph node metastasis and distant metastasis. A positive correlation was found between IRGPI and the infiltration levels of neutrophils, dendritic cells, CD8+ T cells and B cells. Our results demonstrated the clinical significance and potential function of IRGs, providing additional data for prognostic risk prediction and immunotherapeutic target selection in RCC.

Case Report of Immuno-Oncotherapy (IO) Provoked Encephalitis Mimicking Brain Metastasis in a Patient with History of Traumatic Brain Injury

BACKGROUND

Immuno-oncotherapy (IO) has revolutionized systemic cancer care but remains experimental in brain tumors. IO treatment risks multiorgan autoimmune inflammatory responses that limit its use. The central nervous system (CNS) is an immune-specialized compartment with restricted cellular access, thus fewer cases are reported for immune-mediated encephalitis. Interestingly, patients with history of blood-brain barrier compromise are potentially at higher risk for immune cell trafficking to the CNS.

CASE DESCRIPTION

We report the first case, to our knowledge, of a 70-year-old man with clear cell renal cell carcinoma with pulmonary metastases treated with lung irradiation, nephrectomy, and chemotherapy prior to switching to single-agent nivolumab IO. The patient presented with new-onset generalized tonic-clonic seizure and left visual field-cut. Review of patient history revealed remote traumatic brain injury (TBI). Brain imaging noted a solid-enhancing right occipital mass that was presumed metastasis versus lymphoma. Cerebrospinal fluid cytology was negative for malignancy but concerning for lymphoproliferative process not determined to be malignant. The patient started steroids and anti-epileptic therapy. After negative systemic cancer re-staging, IO was discontinued and steroids were initiated with demonstrated patient clinical improvement.

CONCLUSIONS

We concluded the diagnosis of immune-mediated encephalitis secondary to IO with collection of reactive T-cells within the area of encephalomalacia. The area of encephalomalacia from prior TBI served to compartmentalize the reactive lymphocytes, giving the appearance of a mass. Taken together, new onset seizure in patients on IO might signal encephalitis and CNS metastatic mimicry should be considered in patients with a prior history of TBI and encephalomalacia.

Auranofin-Based Analogues Are Effective Against Clear Cell Renal Carcinoma In Vivo and Display No Significant Systemic Toxicity

Effective pharmacological treatments for patients with advanced clear cell renal carcinoma (ccRCC) are limited. Bimetallic titanium-gold containing compounds exhibit significant cytotoxicity against ccRCC in vitro and in vivo and inhibit invasion and angiogenisis in vitro and markers driving these phenomena. However, in vivo preclinical evaluations of such compounds have not examined their pharmacokinetics, pathology, and hematology. Here we use NOD.CB17-Prkdc SCID/J mice bearing xenograft ccRCC Caki-1 tumors to evaluate the in vivo efficacies of two titanium-gold compounds Titanocref and Titanofin (based on auranofin analogue scaffolds) accompanied by pharmacokinetic and pathology studies. A therapeutic trial was performed over 21 days at 5 mg/kg/72h of Titanocref and 10 mg/kg/72h of Titanofin tracking changes in tumor size. We observed a significant reduction of 51% and 60%, respectively (p < 0.01) in tumor size in the Titanocref- and Titanofin-treated mice compared to the starting size, while the vehicle-treated mice exhibited a tumor size increase of 138% (p < 0.01). Importantly, no signs of pathological complication as a result of treatment were found. In addition, Titanocref and Titanofin treatment reduced angiogenesis by 38% and 54%, respectively. Microarray and qRT-PCR analysis of ccRCC Caki-1 cells treated with Titanocref revealed that the compound alters apoptosis, JNK MAP kinase, and ROS pathways within 3 h of treatment. We further show activation of apoptosis by Titanocref and Titanofin in vivo by caspase 3 assay. Titanocref is active against additional kidney cancer cells. Titanocref and Titanofin are therefore promising candidates for further evaluation toward clinical application in the treatment of ccRCC.

Perivascular Neuropilin-1 expression is an independent marker of improved survival in renal cell carcinoma

Renal cell carcinoma (RCC) treatment has improved in the last decade with the introduction of drugs targeting tumor angiogenesis. However, the 5‐year survival of metastatic disease is still only 10–15%. Here, we explored the prognostic significance of compartment‐specific expression of Neuropilin 1 (NRP1), a co‐receptor for vascular endothelial growth factor (VEGF). NRP1 expression was analyzed in RCC tumor vessels, in perivascular tumor cells, and generally in the tumor cell compartment. Moreover, complex formation between NRP1 and the main VEGF receptor, VEGFR2, was determined. Two RCC tissue microarrays were used; a discovery cohort consisting of 64 patients and a validation cohort of 314 patients. VEGFR2/NRP1 complex formation in cis (on the same cell) and trans (between cells) configurations was determined by in situ proximity ligation assay (PLA), and NRP1 protein expression in three compartments (endothelial cells, perivascular tumor cells, and general tumor cell expression) was determined by immunofluorescent staining. Expression of NRP1 in perivascular tumor cells was explored as a marker for RCC survival in the two RCC cohorts. Results were further validated using a publicly available gene expression dataset of clear cell RCC (ccRCC). We found that VEGFR2/NRP1 trans complexes were detected in 75% of the patient samples. The presence of trans VEGFR2/NRP1 complexes or perivascular NRP1 expression was associated with a reduced tumor vessel density and size. When exploring NRP1 as a biomarker for RCC prognosis, perivascular NRP1 and general tumor cell NRP1 protein expression correlated with improved survival in the two independent cohorts, and significant results were obtained also at the mRNA level using the publicly available ccRCC gene expression dataset. Only perivascular NRP1 expression remained significant in multivariable analysis. Our work shows that perivascular NRP1 expression is an independent marker of improved survival in RCC patients, and reduces tumor vascularization by forming complexes in trans with VEGFR2 in the tumor endothelium. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Spatial proximity between T and PD-L1 expressing cells as a prognostic biomarker for oropharyngeal squamous cell carcinoma

Background

Fulfilling the promise of cancer immunotherapy requires novel predictive biomarkers to characterise the host immune microenvironment. Deciphering the complexity of immune cell interactions requires an automated multiplex approach to histological analysis of tumour sections. We tested a new automatic approach to select tissue and quantify the frequencies of cell-cell spatial interactions occurring in the PD1/PD-L1 pathway, hypothesised to reflect immune escape in oropharyngeal squamous cell carcinoma (OPSCC).

Methods

Single sections of diagnostic biopsies from 72 OPSCC patients were stained using multiplex immunofluorescence (CD8, PD1, PD-L1, CD68). Following multispectral scanning and automated regions-of-interest selection, the Hypothesised Interaction Distribution (HID) method quantified spatial proximity between cells. Method applicability was tested by investigating the prognostic significance of co-localised cells (within 30 μm) in patients stratified by HPV status.

Results

High frequencies of proximal CD8⁺ and PD-L1⁺ (HR 2.95, p = 0.025) and PD1⁺ and PD-L1⁺ (HR 2.64, p = 0.042) cells were prognostic for poor overall survival in patients with HPV negative OPSCC (n = 31).

Conclusion

The HID method can quantify spatial interactions considered to reflect immune escape and generate prognostic information in OPSCC. The new automated approach is ready to test in additional cohorts and its applicability should be explored in research and clinical studies.

An essential role for GLUT5-mediated fructose utilization in exacerbating the malignancy of clear cell renal cell carcinoma

Fructose is an important alternative carbon source for several tumors, and GLUT5 is the major fructose transporter which mediates most of fructose uptake in cells. So far, it is unclear whether GLUT5-mediated fructose utilization is important for clear cell renal cell carcinoma (ccRCC). Here, we demonstrated that GLUT5 was highly expressed in a panel of ccRCC cell lines. High GLUT5 expression exacerbated the neoplastic phenotypes of ccRCC cells, including cell proliferation and colony formation. On the other hand, deletion of the GLUT5-encoding gene SLC2A5 dramatically attenuated cellular malignancy via activating the apoptotic pathway. Moreover, administration of 2,5-anhydro-D-mannitol (2,5-AM), a competitive inhibitor of fructose uptake, could markedly suppress ccRCC cell growth. Together, we provide a new mechanistic insight for GLUT5-mediated fructose utilization in ccRCC cells and highlight the therapeutic potential for targeting this metabolic pathway against ccRCC.

The Identification of Immunological Biomarkers in Kidney Cancers

The recent approval of several agents have revolutionized the scenario of therapeutic management of metastatic renal cell carcinoma (RCC) allowing us to reach important clinical end points with extended patients' survival. Actually, every new drug approved has represented an important step forward to the improvement of patient's survival. On the other hand, we now understand that RCC includes a large group of tumor entities, each of them with different genetic and mutational alterations, but also showing different clinical behavior; a reason behind the needs of subtype specific personalized approach to therapy of RCC. Immunotherapy is gradually becoming a key factor in the therapeutic algorithm for patients with locally advanced or metastatic RCC. Due to the combination of potent treatment success and potentially deadly adverse effects from immune checkpoint inhibitors (ICI), gathering prognostic and predictive information about FDA-indicated tumors seems to be prudent. Robust and reliable biomarkers are crucial for patient's selection of treatments with immunomodulatory drugs. PD-L1 expression is a poor prognostic factor and predictive of better responses from both PD-1 and PD-L1 inhibitors in a variety of tumor types including RCC. Each FDA approved PD-1/PD-L1 drug is paired with a PD-L1 Immunohistochemistry (IHC) assay. Thus, there is need for improved knowledge and application of PD-1/PD-L1 IHC biomarkers in daily practice. IHC staining appears in membranous fashion. The atezolizumab approved IHC assay is unique in that only immune cell staining is quantified for the use of this assay in RCC. A single biomarker for patient selection may not be feasible, given that immune responses are dynamic and evolve over time. Biomarker development for ICI drugs will likely require integration of multiple biologic components like PD-L1 expression, TILs and mutational load. New methodological approaches based on digital pathology may be relevant since they will allow recognition of the biomarker and to objectively quantitate its expression, and therefore might produce objective and reproducible cut-off assessment. Multidisciplinary approach is very much needed to fully develop the current and future value of ICI in clinical practice.

A minority-group of renal cell cancer patients with high infiltration of CD20+B-cells is associated with poor prognosis

Background

The role of B-lymphocytes in solid tumours is unclear. Tumour biology studies have implied both anti- and pro-tumoural effects and prognostic studies have mainly linked B-cells to increased survival. This study aimed to analyse the clinical relevance of B-lymphocytes in renal cell cancer (RCC), where information on the prognostic impact is lacking.

Methods

Following immunohistochemistry (IHC) stainings with a CD20 antibody, density of CD20+ B-cells was quantified in an RCC discovery- and validation cohort. Associations of B-cell infiltration, determined by CD20 expression or a B-cell gene-signature, and survival was also analysed in 14 publicly available gene expression datasets of cancer, including the kidney clear cell carcinoma (KIRC) dataset.

Results

IHC analyses of the discovery cohort identified a previously unrecognised subgroup of RCC patients with high infiltration of CD20+ B-cells. The B-cell-high subgroup displayed significantly shorter survival according to uni- and multi-variable analyses. The association between poor prognosis and high density of CD20+ B-cells was confirmed in the validation cohort. Analyses of the KIRC gene expression dataset using the B-cell signature confirmed findings from IHC analyses. Analyses of other gene expression datasets, representing 13 different tumour types, indicated that the poor survival-association of B-cells occurred selectively in RCC.

Conclusion

This exploratory study identifies a previously unrecognised poor-prognosis subset of RCC with high density of CD20-defined B-cells.

Capn4 contributes to tumor invasion and metastasis in clear cell renal cell carcinoma cells via modulating talin-focal adhesion kinase signaling pathway

Calpain small subunit 1 (Capn4) has been shown to correlate with the metastasis/invasion of clear cell renal cell carcinoma (ccRCC). This study aimed to further elucidate the molecular mechanisms underlying Capn4-mediated ccRCC progression. The mRNA expression levels in ccRCC cells were measured by quantitative real-time PCR. The effects of Capn4 on cell adhesion, invasion, and migration were examined by cell adhesion assay, cell invasion assay, and wound-healing assay, respectively. The protein levels were detected by western blot analysis. The effect of Capn4 on cancer metastasis in vivo was assessed in a nude mice xenograft model. It was found that Capn4 was up-regulated in the ccRCC cells, and Capn4 overexpression suppressed cell adhesion activity and increased cell invasion and migration in 786-O cells, while Capn4 silencing increased cell adhesion activity and impaired the invasion and migration ability of Caki-1 cells. Capn4 overexpression also increased the protein level of cleaved talin in 786-O cells, while Capn4 silencing decreased the protein level of cleaved talin in Caki-1 cells. The focal adhesion kinase (FAK)/AKT/MAPK signaling was activated by Capn4 overexpression in 786-O cells, and was inhibited by Capn4 down-regulation in Caki-1 cells. Capn4 overexpression increased the protein levels of matrix metalloproteinase 2 (MMP-2), vimentin, N-cadherin, and down-regulated E-cadherin in 786-O cells, while Capn4 silencing decreased the protein levels of MMP-2, vimentin, N-cadherin, and up-regulated E-cadherin in Caki-1 cells. Capn4 also promoted cancer metastasis in the in vivo nude mice xenograft model. Our results implicate the functional role of Capn4 in ccRCC invasion and migration, which may contribute to cancer metastasis in ccRCC.

The Correlation Between the Immune and Epithelial-Mesenchymal Transition Signatures Suggests Potential Therapeutic Targets and Prognosis Prediction Approaches in Kidney Cancer

Both epithelial-mesenchymal transition (EMT) and immune regulation are important biological process in malignant tumours. The current research aims to comprehensively explore the potential association between the epithelial-mesenchymal transition (EMT) signature and immune checkpoint signature and its role in predicting the prognosis of clear-cell renal cell carcinoma (ccRCC) patients. EMT-related genes were collected from an experiment-based study and then were investigated using data from the Cancer Genome Atlas. A total of 357 genes were included, and 23 of them that were upregulated and correlated with prognosis were analysed further as core EMT genes in ccRCC. Interestingly, the emerging immune checkpoints CD276, OX40 and TGFB1 were found to be significantly co-expressed with core EMT genes, and TGFB1, CXCR4, IL10, and IL6 were the most important molecules potentially interacting with EMT molecules in our model, as determined from mRNA co-expression and protein-protein interaction network analysis. Additionally, an integrated scoring model based on FOXM1, TIMP1 and IL6 was successfully established to distinguish ccRCC patients with different clinical risks. Our results identified core genes in the EMT-immunophenotyping correlation and evaluated their risk assessment capabilities, providing more potential therapeutic targets and prediction approaches regarding the translational research of treatment and prognosis in ccRCC.

A Genetic Polymorphism in CTLA-4 Is Associated with Overall Survival in Sunitinib-Treated Patients with Clear Cell Metastatic Renal Cell Carcinoma

Purpose: The survival of patients with clear cell metastatic renal cell carcinoma (cc-mRCC) has improved substantially since the introduction of tyrosine kinase inhibitors (TKI). With the fact that TKIs interact with immune responses, we investigated whether polymorphisms of genes involved in immune checkpoints are related to the clinical outcome of cc-mRCC patients treated with sunitinib as first TKI.Experimental Design: Twenty-seven single-nucleotide polymorphisms (SNP) in CD274 (PD-L1), PDCD1 (PD-1), and CTLA-4 were tested for a possible association with progression-free survival (PFS) and overall survival (OS) in a discovery cohort of 550 sunitinib-treated cc-mRCC patients. SNPs with a significant association (P < 0.05) were tested in an independent validation cohort of 138 sunitinib-treated cc-mRCC patients. Finally, data of the discovery and validation cohort were pooled for meta-analysis.Results:CTLA-4 rs231775 and CD274 rs7866740 showed significant associations with OS in the discovery cohort after correction for age, gender, and Heng prognostic risk group [HR, 0.84; 95% confidence interval (CI), 0.72-0.98; P = 0.028, and HR, 0.73; 95% CI, 0.54-0.99; P = 0.047, respectively]. In the validation cohort, the associations of both SNPs with OS did not meet the significance threshold of P < 0.05. After meta-analysis, CTLA-4 rs231775 showed a significant association with OS (HR, 0.83; 95% CI, 0.72-0.95; P = 0.008). Patients with the GG genotype had longer OS (35.1 months) compared with patients with an AG (30.3 months) or AA genotype (24.3 months). No significant associations with PFS were found.Conclusions: The G-allele of rs231775 in the CTLA-4 gene is associated with an improved OS in sunitinib-treated cc-mRCC patients and could potentially be used as a prognostic biomarker. Clin Cancer Res; 24(10); 2350-6. ©2018 AACR.

State of the Art Treatment of Spinal Metastatic Disease

Treatment paradigms for patients with spine metastases have evolved significantly over the past decade. Incorporating stereotactic radiosurgery into these paradigms has been particularly transformative, offering precise delivery of tumoricidal radiation doses with sparing of adjacent tissues. Evidence supports the safety and efficacy of radiosurgery as it currently offers durable local tumor control with low complication rates even for tumors previously considered radioresistant to conventional radiation. The role for surgical intervention remains consistent, but a trend has been observed toward less aggressive, often minimally invasive, techniques. Using modern technologies and improved instrumentation, surgical outcomes continue to improve with reduced morbidity. Additionally, targeted agents such as biologics and checkpoint inhibitors have revolutionized cancer care, improving both local control and patient survivals. These advances have brought forth a need for new prognostication tools and a more critical review of long-term outcomes. The complex nature of current treatment schemes necessitates a multidisciplinary approach including surgeons, medical oncologists, radiation oncologists, interventionalists, and pain specialists. This review recapitulates the current state-of-the-art, evidence-based data on the treatment of spinal metastases, integrating these data into a decision framework, NOMS, which integrates the 4 sentinel decision points in metastatic spine tumors: Neurologic, Oncologic, Mechanical stability, and Systemic disease and medical co-morbidities.

Cell death-based approaches in treatment of the urinary tract-associated diseases: a fight for survival in the killing fields

Urinary tract-associated diseases comprise a complex set of disorders with a variety of etiologic agents and therapeutic approaches and a huge global burden of disease, estimated at around 1 million deaths per year. These diseases include cancer (mainly prostate, renal, and bladder), urinary tract infections, and urolithiasis. Cell death plays a key role in the pathogenesis and therapy of these conditions. During urinary tract infections, invading bacteria may either promote or prevent host cell death by interfering with cell death pathways. This has been studied in detail for uropathogenic E. coli (UPEC). Inhibition of host cell death may allow intracellular persistence of live bacteria, while promoting host cell death causes tissue damage and releases the microbes. Both crystals and urinary tract obstruction lead to tubular cell death and kidney injury. Among the pathomechanisms, apoptosis, necroptosis, and autophagy represent key processes. With respect to malignant disorders, traditional therapeutic efforts have focused on directly promoting cancer cell death. This may exploit tumor-specific characteristics, such as targeting Vascular Endothelial Growth Factor (VEGF) signaling and mammalian Target of Rapamycin (mTOR) activity in renal cancer and inducing survival factor deprivation by targeting androgen signaling in prostate cancer. An area of intense research is the use of immune checkpoint inhibitors, aiming at unleashing the full potential of immune cells to kill cancer cells. In the future, this may be combined with additional approaches exploiting intrinsic sensitivities to specific modes of cell death such as necroptosis and ferroptosis. Here, we review the contribution of diverse cell death mechanisms to the pathogenesis of urinary tract-associated diseases as well as the potential for novel therapeutic approaches based on an improved molecular understanding of these mechanisms.

The efficacy and safety of anti-PD-1/PD-L1 antibody therapy versus docetaxel for pretreated advanced NSCLC: a meta-analysis

Antibodies against the immune checkpoint proteins PD-1 and PD-L1 are novel therapeutic drugs for the treatment of advanced non-small cell lung cancer (NSCLC). Many clinical trials involving these drugs achieved breakthroughs in patients previously treated for advanced NSCLC. However, the results of these clinical studies are not consistent. In this report, we performed a meta-analysis to assess the efficacy and safety of anti-PD-1/PD-L1 antibodies compared with docetaxel treatment for advanced NSCLC patients from 5 randomized clinical trials. We demonstrated that the patients in anti-PD-1/PD-L1 antibody therapy groups had significantly longer overall survival (OS) (HR = 0.69, 95% CI 0.63-0.75, P < 0.05) and progression-free survival (PFS) (HR = 0.76, 95% CI 0.63-0.92, P < 0.05) than those in chemotherapy groups, especially PD-L1 positive patients. Anti-PD-1/PD-L1 antibodies improved the objective response rate (ORR) compared with docetaxel (OR = 1.64, 95% CI 1.19-2.26, p < 0.05). In addition, the anti-PD-1/PD-L1 antibody therapy had fewer treatment-related adverse events (AEs) (OR = 0.33, 95% CI 0.28-0.39, P < 0.05) than docetaxel, especially the grade ≥3 AEs (OR = 0.18, 95% CI 0.12-0.28, P < 0.001). In conclusion, our study revealed that, compared with docetaxel, anti-PD-1/PD-L1 antibody therapy improved clinical efficacy and safety in previously treated advanced NSCLC patients. This therapy may be a promising treatment for advanced NSCLC patients.

Employing RNA viruses to fight cancer: novel insights into oncolytic virotherapy

Within recent decades, viruses that specifically target tumor cells have emerged as novel therapeutic agents against cancer. These viruses do not only act via their cell-lytic properties, but also harbor immunostimulatory features to re-direct the tumor microenvironment and stimulate tumor-directed immune responses. Furthermore, oncolytic viruses are considered to be superior to classical cancer therapies due to higher selectivity towards tumor cell destruction and, consequently, less collateral damage of non-transformed healthy tissue. In particular, the field of oncolytic RNA viruses is rapidly developing since these agents possess alternative tumor-targeting strategies compared to established oncolytic DNA viruses. Thus, oncolytic RNA viruses have broadened the field of virotherapy facilitating new strategies to fight cancer. In addition to several naturally occurring oncolytic viruses, genetically modified RNA viruses that are armed to express foreign factors such as immunostimulatory molecules have been successfully tested in early clinical trials showing promising efficacy. This review aims to provide an overview of the most promising RNA viruses in clinical development, to summarize the current knowledge of clinical trials using these viral agents, and to discuss the main issues as well as future perspectives of clinical approaches using oncolytic RNA viruses.

Novel immunotherapy in metastatic renal cell carcinoma

Despite the rapid development of therapeutic modalities for metastatic renal cell carcinoma (mRCC) over the past decade to include a number of targeted antiangiogenic therapies and traditional immunotherapy, such as high-dose interleukin-2 and interferon-α, mRCC continues to be associated with poor prognosis. Currently, several novel immunotherapy agents, such as cancer vaccines, adoptive cell therapy, and checkpoint inhibitors, such as programmed cell death-1 (PD-1 present on T cells), one of its ligands (PD-L1 present on antigen-presenting cells and tumor cells), and cytotoxic T-lymphocyte-associated protein-4 pathways, are being studied in mRCC and are showing promise as important steps in the management of this disease. This review summarizes the current landscape of standard and emerging immune therapeutics and other modalities for mRCC.

Combined mutation in Vhl, Trp53 and Rb1 causes clear cell renal cell carcinoma in mice

Clear cell renal cell carcinomas (ccRCC) frequently exhibit inactivation of the VHL tumour suppressor gene and often harbour multiple copy number alterations in genes that regulate cell cycle progression. We show here that modelling these genetic alterations by combined renal epithelium-specific deletion of Vhl, Trp53 and Rb1 in mice caused ccRCC. These tumours arose from proximal tubule epithelial cells and shared molecular markers and mRNA expression profiles with human ccRCC. Exome sequencing revealed that mouse and human ccRCCs exhibit recurrent mutations in genes associated with the primary cilium, uncovering a mutational convergence on this organelle and implicating a subset of ccRCCs as genetic ciliopathies. Different mouse tumours responded differently to standard therapies for advanced human ccRCC, mimicking the range of clinical behaviours in the human disease. Inhibition of HIF-α transcription factors with Acriflavine as third line therapy had therapeutic effects in some tumours, providing pre-clinical evidence for further investigation of HIF-α inhibition as a ccRCC treatment. This autochthonous mouse ccRCC model represents a tool to investigate the biology of ccRCC and to identify new treatment strategies.