Immunotherapy in renal cell carcinoma: latest evidence and clinical implications

Identification of tumor-antigen signatures and immune subtypes for messenger RNA vaccine selection in advanced clear cell renal cell carcinoma

BACKGROUND

Advanced clear cell renal cell carcinoma still lacks reliable diagnostic and prognostic biomarkers. Recently, tumor vaccines targeting specific molecules have been proposed as a promising treatment in mitigating tumor progression, which was rekindled under the background of the COVID-19 pandemic. However, the application of messenger RNA vaccine against advanced clear cell renal cell carcinoma antigens remains stagnant, and no subgroup of patients deemed suitable for vaccination has been extensively studied or validated. Our study aims to explore novel advanced clear cell renal cell carcinoma antigen signatures to select suitable patients for vaccination.

METHODS

Gene expression profiles of advanced clear cell renal cell carcinoma samples and their corresponding clinical data were retrieved from The Cancer Genome Atlas. The least absolute shrinkage and selection operator model was applied to develop signatures to stratify patients with advanced clear cell renal cell carcinoma. Receiver operating characteristic analysis was used to compare the prognostic accuracy of each factor. Tumor Immune Estimation Resource was used to visualize the relationship between the proportion of antigen-presenting cells and the expression of filtered genes. The "CIBERSORT" and "WGCNA" R Packages were employed to ascertain disparities in immune infiltration levels between advanced clear cell renal cell carcinoma subgroups. The Search Tools for the Retrieval of Interacting Genes database and Cytoscape were used to construct the protein-protein interaction network. CCK-8 and colony formation assays were included in the invitro experiment.

RESULTS

In total, 244 potential tumor antigens were identified. Using the least absolute shrinkage and selection operator Cox regression, 21 tumor antigens were selected for developing a risk evaluation signature. The risk score signature can be a useful tool to predict the outcome of advanced clear cell renal cell carcinoma patients. According to the differential clinical, molecular, and immune-related genes, we divided advanced clear cell renal cell carcinoma patients into the immune "cold" subtype and immune "hot" subtype. By developing a logistic score, the immune subtype signature can better distinguish a patient more likely to be immune "cold" subtype or immune "hot" subtype. Interestingly, patients with high risk scores had a higher proportion of immune "hot" subtype than those with a low risk score. Furthermore, the prognostic value was significantly improved when combining risk score and immune subtype. Distinct immune landscapes and signal pathways were observed between different tumor subtypes. Finally, novel tumor antigens related to oxidative stress were identified.

CONCLUSION

The tumor-antigens-based risk score and immune subtype signatures identified potentially effective neo-antigens for advanced clear cell renal cell carcinoma messenger RNA vaccine development, and patients with low risk scores and immune "cold" subtype tumors are more prone to benefit from messenger RNA vaccination. Furthermore, our study highlights the significant role of oxidative stress in determining the efficacy of the messenger RNA vaccine.

ANGPTL4 Suppresses Clear Cell Renal Cell Carcinoma via Inhibition of Lysosomal Acid Lipase

Renal cell carcinoma (RCC), the most common form of kidney cancer, is a heterogeneous disease with clear cell RCC (ccRCC) being the most prevalent and aggressive subtype. While most ccRCC tumors have elevated expression of angiopoietin-like4 (ANGPTL4), in our study we identified a significant subset of patients whose cancers show no increase in ANGPTL4 expression. These patients have a worse prognosis compared to the patients with high expression of ANGPTL4. These ANGPTL4-low cancers are characterized by the increased frequency of wild-type Von Hippel-Lindau(WT VHL), a gene that is commonly mutated in ccRCC, and an enrichment for genes associated with lipid metabolism. Using RCC tumor models with WT VHL, we demonstrate that ANGPTL4 behaves as a tumor suppressor. The loss of ANGPTL4 in ccRCC cell lines results in increased tumor growth and colony formation in a lysosomal acid lipase (LAL)-dependent manner, a phenotype rescued by the expression of N-terminus ANGPTL4. At the mechanistic level, the loss of ANGPTL4 increases LAL activity in ccRCC cells. These data suggest that ANGPTL4 enacts its tumor-suppressive effects in ccRCC by regulating LAL activity. Importantly, the identified patient cohort with low ANGPTL4 expression may exhibit increased reliance on lipid metabolism, which can be a point of target for future therapy.

SIGNIFICANCE

Our data indicate angiopoietin-like 4 (ANGPTL4) acts as a tumor suppressor in clear cell renal cell carcinoma via regulating lipid metabolism and identifies a cohort of patients with lower expression of ANGPTL4 that are correlated with shorter survival.

Metabolite profiling of human renal cell carcinoma reveals tissue-origin dominance in nutrient availability

The tumor microenvironment is a determinant of cancer progression and therapeutic efficacy, with nutrient availability playing an important role. Although it is established that the local abundance of specific nutrients defines the metabolic parameters for tumor growth, the factors guiding nutrient availability in tumor compared to normal tissue and blood remain poorly understood. To define these factors in renal cell carcinoma (RCC), we performed quantitative metabolomic and comprehensive lipidomic analyses of tumor interstitial fluid (TIF), adjacent normal kidney interstitial fluid (KIF), and plasma samples collected from patients. TIF nutrient composition closely resembles KIF, suggesting that tissue-specific factors unrelated to the presence of cancer exert a stronger influence on nutrient levels than tumor-driven alterations. Notably, select metabolite changes consistent with known features of RCC metabolism are found in RCC TIF, while glucose levels in TIF are not depleted to levels that are lower than those found in KIF. These findings inform tissue nutrient dynamics in RCC, highlighting a dominant role of non-cancer-driven tissue factors in shaping nutrient availability in these tumors.

Identification of novel snoRNA-based biomarkers for clear cell renal cell carcinoma from urine-derived extracellular vesicles

BACKGROUND

Clear cell renal cell carcinoma (ccRCC) is the most common subtype of RCC with high rates of metastasis. Targeted therapies such as tyrosine kinase and checkpoint inhibitors have improved treatment success, but therapy-related side effects and tumor recurrence remain a challenge. As a result, ccRCC still have a high mortality rate. Early detection before metastasis has great potential to improve outcomes, but no suitable biomarker specific for ccRCC is available so far. Therefore, molecular biomarkers derived from body fluids have been investigated over the past decade. Among them, RNAs from urine-derived extracellular vesicles (EVs) are very promising.

METHODS

RNA was extracted from urine-derived EVs from a cohort of 78 subjects (54 ccRCC patients, 24 urolithiasis controls). RNA-seq was performed on the discovery cohort, a subset of the whole cohort (47 ccRCC, 16 urolithiasis). Reads were then mapped to the genome, and expression was quantified based on 100 nt long contiguous genomic regions. Cluster analysis and differential region expression analysis were performed with adjustment for age and gender. The candidate biomarkers were validated by qPCR in the entire cohort. Receiver operating characteristic, area under the curve and odds ratios were used to evaluate the diagnostic potential of the models.

RESULTS

An initial cluster analysis of RNA-seq expression data showed separation by the subjects' gender, but not by tumor status. Therefore, the following analyses were done, adjusting for gender and age. The regions differentially expressed between ccRCC and urolithiasis patients mainly overlapped with small nucleolar RNAs (snoRNAs). The differential expression of four snoRNAs (SNORD99, SNORD22, SNORD26, SNORA50C) was validated by quantitative PCR. Confounder-adjusted regression models were then used to classify the validation cohort into ccRCC and tumor-free subjects. Corresponding accuracies ranged from 0.654 to 0.744. Models combining multiple genes and the risk factors obesity and hypertension showed improved diagnostic performance with an accuracy of up to 0.811 for SNORD99 and SNORA50C (p = 0.0091).

CONCLUSIONS

Our study uncovered four previously unrecognized snoRNA biomarkers from urine-derived EVs, advancing the search for a robust, easy-to-use ccRCC screening method.

Metabolite profiling of human renal cell carcinoma reveals tissue-origin dominance in nutrient availability

The tumor microenvironment is a determinant of cancer progression and therapeutic efficacy, with nutrient availability playing an important role. Although it is established that the local abundance of specific nutrients defines the metabolic parameters for tumor growth, the factors guiding nutrient availability in tumor compared to normal tissue and blood remain poorly understood. To define these factors in renal cell carcinoma (RCC), we performed quantitative metabolomic and comprehensive lipidomic analyses of tumor interstitial fluid (TIF), adjacent normal kidney interstitial fluid (KIF), and plasma samples collected from patients. TIF nutrient composition closely resembles KIF, suggesting that tissue-specific factors unrelated to the presence of cancer exert a stronger influence on nutrient levels than tumor-driven alterations. Notably, select metabolite changes consistent with known features of RCC metabolism are found in RCC TIF, while glucose levels in TIF are not depleted to levels that are lower than those found in KIF. These findings inform tissue nutrient dynamics in RCC, highlighting a dominant role of non-cancer driven tissue factors in shaping nutrient availability in these tumors.

SETD2 Loss and ATR Inhibition Synergize to Promote cGAS Signaling and Immunotherapy Response in Renal Cell Carcinoma

PURPOSE

Immune checkpoint blockade (ICB) demonstrates durable clinical benefits in a minority of patients with renal cell carcinoma (RCC). We aimed to identify the molecular features that determine the response and develop approaches to enhance it.

EXPERIMENTAL DESIGN

We investigated the effects of SET domain-containing protein 2 (SETD2) loss on the DNA damage response pathway, the cytosolic DNA-sensing pathway, the tumor immune microenvironment, and the response to ataxia telangiectasia and rad3-related (ATR) and checkpoint inhibition in RCC.

RESULTS

ATR inhibition activated the cyclic GMP-AMP synthase (cGAS)-interferon regulatory factor 3 (IRF3)-dependent cytosolic DNA-sensing pathway, resulting in the concurrent expression of inflammatory cytokines and immune checkpoints. Among the common RCC genotypes, SETD2 loss is associated with preferential ATR activation and sensitizes cells to ATR inhibition. SETD2 knockdown promoted the cytosolic DNA-sensing pathway in response to ATR inhibition. Treatment with the ATR inhibitor VE822 concurrently upregulated immune cell infiltration and immune checkpoint expression in Setd2 knockdown Renca tumors, providing a rationale for ATR inhibition plus ICB combination therapy. Setd2-deficient Renca tumors demonstrated greater vulnerability to ICB monotherapy or combination therapy with VE822 than Setd2-proficient tumors. Moreover, SETD2 mutations were associated with a higher response rate and prolonged overall survival in patients with ICB-treated RCC but not in patients with non-ICB-treated RCC.

CONCLUSIONS

SETD2 loss and ATR inhibition synergize to promote cGAS signaling and enhance immune cell infiltration, providing a mechanistic rationale for the combination of ATR and checkpoint inhibition in patients with RCC with SETD2 mutations.

Molecular Targets of Shenqi Dihuang, A Traditional Chinese Herbal Medicine, and Its Potential Role in Renal Cell Carcinoma Therapy

Chinese herbal medicine (CHM), which includes herbal slices and proprietary products, is widely used in China. Shenqi Dihuang (SQDH) is a traditional Chinese medicine (TCM) formula with ingredients that affect tumor growth. Despite recent advances in prognosis, patients with renal cell carcinoma (RCC) cannot currently receive curative treatment. The present study aimed to explore the potential target genes closely associated with SQDH. The gene expression data for SQDH and RCC were obtained from the TCMSP and TCGA databases. The SQDH-based prognostic prediction model reveals a strong correlation between RCC and SQDH. In addition, the immune cell infiltration analysis indicated that SQDH might be associated with the immune response of RCC patients. Based on this, we successfully built the prognostic prediction model using SQDH-related genes. The results demonstrated that CCND1 and NR3C2 are closely associated with the prognosis of RCC patients. Finally, the pathways enrichment analysis revealed that response to oxidative stress, cyclin binding, programmed cell death, and immune response are the most enriched pathways in CCND1. Furthermore, transcription regulator activity, regulation of cell population proliferation, and cyclin binding are closely associated with the NR3C2.

Comparing efficacy and safety of first-line treatment of metastatic renal cell carcinoma: A Bayesian network meta-regression analysis

Background

This Bayesian network meta-regression analysis provides a head-to-head comparison of first-line therapeutic immune checkpoint inhibitors (ICI) and tyrosine kinase inhibitors (TKI) combinations for metastatic renal cell carcinoma (mRCC) using median follow-up time as covariate.

Methods

We searched Six databases for a comprehensive analysis of randomised clinical trials (RCTs). Comparing progression free survival (PFS) and overall survival (OS) of different interventions at the same time node by Bayesian network meta-analysis. Bayesian network meta-regression analysis was performed on objective response rate (ORR), adverse events (AEs) (grade ≥ 3) and the hazard ratios (HR) associated with PFS and OS, with the median follow-up time as the covariate.

Results

Eventually a total of 22 RCTs reporting 11,090 patients with 19 interventions. Lenvatinib plus Pembrolizumab (LenPem) shows dominance of PFS, and Pembrolizumab plus Axitinib (PemAxi) shows superiority in OS at each time point. After meta-regression analysis, for HRs of PFS, LenPem shows advantages; for HRs of OS, PemAxi shows superiority; For ORR, LenPem provides better results. For AEs (grade ≥ 3), Atezolizumab plus Bevacizumab (AtezoBev) is better.

Conclusion

Considering the lower toxicity and the higher quality of life, PemAxi should be recommended as the optimal therapy in treating mRCC.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD4202236775.

ImmunoPET Imaging with 89Zr-Labeled Atezolizumab Enables In Vivo Evaluation of PD-L1 in Tumorgraft Models of Renal Cell Carcinoma

PURPOSE

Immune checkpoint inhibitors (ICI) targeting the programmed cell death protein 1 and its ligand (PD-1/PD-L1) have transformed the treatment paradigm for metastatic renal cell carcinoma (RCC). However, response rates to ICIs as single agents or in combination vary widely and predictive biomarkers are lacking. Possibly related to the heterogeneity and dynamic nature of PD-L1 expression, tissue-based methods have shown limited value. Immuno-positron emission tomography (immunoPET) may enable noninvasive, comprehensive, and real-time PD-L1 detection. Herein, we systematically examined the performance of immunoPET for PD-L1 detection relative to IHC in an RCC patient-derived tumorgraft (TG) platform.

EXPERIMENTAL DESIGN

Eight independent RCC TGs with a wide range of PD-L1 expression (0%-85%) were evaluated by immunoPET. Uptake of 89Zr-labeled atezolizumab ([89Zr]Zr-DFO-ATZ) was compared with PD-L1 expression in tumors by IHC through double-blind analyses. Clinical outcomes of ICI-treated patients whose TGs were examined were analyzed to evaluate the clinical role of immunoPET in RCC.

RESULTS

ImmunoPET with [89Zr]Zr-DFO-ATZ (day 6/7 postinjection) revealed a statistically significant association with PD-L1 IHC assays (P = 0.0014; correlation ρXY = 0.78). Furthermore, immunoPET can be used to assess the heterogeneous distribution of PD-L1 expression. Finally, studies in the corresponding patients (n = 4) suggest that PD-L1 signal may influence ICI responsiveness.

CONCLUSIONS

ImmunoPET with [89Zr]Zr-DFO-ATZ may enable a thorough and dynamic assessment of PD-L1 across sites of disease. The power of immunoPET to predict ICI response in RCC is being explored in an ongoing clinical trial (NCT04006522).

The integrated landscape of eRNA in gastric cancer reveals distinct immune subtypes with prognostic and therapeutic relevance

The comprehensive regulation effect of eRNA on tumor immune cell infiltration and the outcome remains obscure. We comprehensively identify the eRNA-mediated immune infiltration patterns of gastric cancer (GC) samples. We creatively proposed a random forest machine-learning (ML) algorithm to map eRNA to mRNA expression patterns. The eRNA score was constructed using principal component analysis algorithms and validated in an independent cohort. Three subtypes with distinct eRNA expression patterns were determined in GC. There were significant differences between the three subtypes in the overall survival rate, immune cell infiltration characteristics, and immunotherapy response indicators. The patients in the high eRNA score group have a higher overall survival rate and might benefit from immunotherapy. This work revealed that eRNA regulation might be a new prognostic index and might offer a potential biomarker in the response of immunotherapy. Evaluating the eRNA regulation manner of GC will contribute to guiding more effective immunotherapy strategies.

The role of gut microbiome in immune modulation in metastatic renal cell carcinoma

Treatment of metastatic renal cell carcinomas (mRCC) has drastically improved since the advent of immunotherapy with immune checkpoint inhibitors (ICIs), with a significant proportion of patients achieving durable responses. While this has revolutionized treatment and improved outcomes for mRCC patients, a large subset of patients still does not respond to treatment with ICIs. Moreover, ICIs can induce various immune-related adverse events, limiting their use in many patients. Therefore, there is a need to identify the predictive biomarkers of both efficacy and toxicity associated with ICIs, which would allow for a more personalized approach and help with clinical decision-making. This review aims to explore the role of the gut microbiome in RCC to overcome primary resistance and predict response to treatment with ICIs. First, current therapeutic strategies and mechanisms of action of ICI therapies for RCC treatment will be reviewed. With the technological development of shotgun whole-genome sequencing, the gut microbiome has emerged as an exciting field of research within oncology. Thus, the role of the microbiome and its bidirectional interaction with ICIs and other drugs will be explored, with a particular focus on the microbiome profile in RCC. Lastly, the rationale for future clinical interventions to overcome resistance to ICIs using fecal microbiota transplantation in patients with RCC will be presented.

Use of Circular RNAs in Diagnosis, Prognosis and Therapeutics of Renal Cell Carcinoma

Renal cell carcinoma is the most common type of kidney cancer, representing 90% of kidney cancer diagnoses, and the deadliest urological cancer. While the incidence and mortality rates by renal cell carcinoma are higher in men compared to women, in both sexes the clinical characteristics are the same, and usually unspecific, thereby hindering and delaying the diagnostic process and increasing the metastatic potential. Regarding treatment, surgical resection remains the main therapeutic strategy. However, even after radical nephrectomy, metastasis may still occur in some patients, with most metastatic renal cell carcinomas being resistant to chemotherapy and radiotherapy. Therefore, the identification of new biomarkers to help clinicians in the early detection, and treatment of renal cell carcinoma is essential. In this review, we describe circRNAs related to renal cell carcinoma processes reported to date and propose the use of some in therapeutic strategies for renal cell carcinoma treatment.

Models of Renal Cell Carcinoma Used to Investigate Molecular Mechanisms and Develop New Therapeutics

Modeling renal cell carcinoma is critical to investigating tumor biology and therapeutic mechanisms. Multiple systems have been developed to represent critical components of the tumor and its surrounding microenvironment. Prominent in vitro models include traditional cell cultures, 3D organoid models, and microphysiological devices. In vivo models consist of murine patient derived xenografts or genetically engineered mice. Each system has unique advantages as well as limitations and researchers must thoroughly understand each model to properly investigate research questions. This review addresses common model systems for renal cell carcinoma and critically evaluates their performance and ability to measure tumor characteristics.

Renal Cell Carcinoma Associated With HIV/AIDS: A Review of the Epidemiology, Risk Factors, Diagnosis, and Treatment

Renal cell carcinoma (RCC), one of the most common genitourinary tumors, is induced by many factors, primarily smoking, obesity, and hypertension. As a non-acquired immunodeficiency syndrome (AIDS)-defining cancer, human immunodeficiency virus (HIV) may also play a critical role in the incidence and progression of RCC. It is evident that individuals who are infected with HIV are more likely than the general population to develop RCC. The age of RCC diagnosis among HIV-positive patients is younger than among HIV-negative individuals. However, many other characteristics remain unknown. With the increase in RCC incidence among HIV-infected patients, more research is being conducted to discover the relationship between RCC and HIV, especially with regard to HIV-induced immunodeficiency, diagnosis, and treatment. Unexpectedly, the majority of the literature suggests that there is no relationship between RCC and HIV-induced immunodeficiency. Nonetheless, differences in pathology, symptoms, or treatment in HIV-positive patients diagnosed with RCC are a focus. In this review, we summarize the association of RCC with HIV in terms of epidemiology, risk factors, diagnosis, and treatment.

Development of a Novel Immune Subtyping System Expanded with Immune Landscape and an 11-Gene Signature for Predicting Prostate Cancer Survival

Background

Nearly half of patients with prostate cancer will develop metastasis. Immunotherapy is currently a promising strategy for treating metastatic prostate cancer. This study aimed to construct an immune subtyping system and provide a more comprehensive understanding of tumor microenvironment.

Methods

Data were downloaded from TCGA database and cBioPortal database. Consensus clustering was used to identify immune subtypes. Immune features were scored by ESTIMATE and CIBERSORT. Efficacy of different subtypes in immunotherapy was predicted by TIDE tool. Immune landscape was delineated through “monocle.” Coexpressed gene modules were identified by weighted correlation network analysis. Univariate Cox regression analysis and LASSO analysis were applied to construct a prognostic model.

Results

Four immune subtypes (IS1 to IS4) were identified. Prognosis, mutation patterns, expression of immune genes, immune biomarkers, immunohistochemical biomarkers, and prediction efficacy of immunotherapy were significantly different among four immune subtypes. Five coexpressed gene modules were identified and an 11-gene prognostic model was constructed based on the modules.

Conclusions

The study developed a novel immune subtyping system and an 11-gene prognostic model of prostate cancer, which could guide personalized treatment and immunotherapy for patients with prostate cancer.

Development and Validation of a Prognostic Gene Signature Correlated With M2 Macrophage Infiltration in Esophageal Squamous Cell Carcinoma

Background

Esophageal squamous cell carcinoma (ESCC) is the most common type of esophageal cancer and the seventh most prevalent cause of cancer-related death worldwide. Tumor microenvironment (TME) has been confirmed to play an crucial role in ESCC progression, prognosis, and the response to immunotherapy. There is a need for predictive biomarkers of TME-related processes to better prognosticate ESCC outcomes.

Aim

To identify a novel gene signature linked with the TME to predict the prognosis of ESCC.

Methods

We calculated the immune/stromal scores of 95 ESCC samples from The Cancer Genome Atlas (TCGA) using the ESTIMATE algorithm, and identified differentially expressed genes (DEGs) between high and low immune/stromal score patients. The key prognostic genes were further analyzed by the intersection of protein–protein interaction (PPI) networks and univariate Cox regression analysis. Finally, a risk score model was constructed using multivariate Cox regression analysis. We evaluated the associations between the risk score model and immune infiltration via the CIBERSORT algorithm. Moreover, we validated the signature using the Gene Expression Omnibus (GEO) database. Within the ten gene signature, five rarely reported genes were further validated with quantitative real time polymerase chain reaction (qRT-PCR) using an ESCC tissue cDNA microarray.

Results

A total of 133 up-regulated genes were identified as DEGs. Ten prognostic genes were selected based on intersection analysis of univariate COX regression analysis and PPI, and consisted of C1QA, C1QB, C1QC, CD86, C3AR1, CSF1R, ITGB2, LCP2, SPI1, and TYROBP (HR>1, p<0.05). The expression of 9 of these genes in the tumor samples were significantly higher compared to matched adjacent normal tissue based on the GEO database (p<0.05). Next, we assessed the ability of the ten-gene signature to predict the overall survival of ESCC patients, and found that the high-risk group had significantly poorer outcomes compared to the low-risk group using univariate and multivariate analyses in the TCGA and GEO cohorts (HR=2.104, 95% confidence interval:1.343-3.295, p=0.001; HR=1.6915, 95% confidence interval:1.053-2.717, p=0.0297). Additionally, receiver operating characteristic (ROC) curve analysis demonstrated a relatively sensitive and specific profile for the signature (1-, 2-, 3-year AUC=0.672, 0.854, 0.81). To identify the basis for these differences in the TME, we performed correlation analyses and found a significant positive correlation with M1 and M2 macrophages and CD8+ T cells, as well as a strong correlation to M2 macrophage surface markers. A nomogram based on the risk score and select clinicopathologic characteristics was constructed to predict overall survival of ESCC patients. For validation, qRT-PCR of an ESCC patient cDNA microarray was performed, and demonstrated that C1QA, C3AR1, LCP2, SPI1, and TYROBP were up-regulated in tumor samples and predict poor prognosis.

Conclusion

This study established and validated a novel 10-gene signature linked with M2 macrophages and poor prognosis in ESCC patients. Importantly, we identified C1QA, C3AR1, LCP2, SPI1, and TYROBP as novel M2 macrophage-correlated survival biomarkers. These findings may identify potential targets for therapy in ESCC patients.

Risk of selected gastrointestinal toxicities in metastatic renal cell carcinoma patients treated with immuno-TKI combinations: a meta-analysis

OBJECTIVE

Recent years have registered the advent of novel treatment options for metastatic renal cell carcinoma (mRCC), including combination therapies with immune checkpoint inhibitors (ICIs) and tyrosine kinase inhibitors (TKIs). Immuno-TKI combinations have been suggested to improve clinical outcomes but may also result in increased toxicity, including gastrointestinal (GI) adverse events.

METHODS

Herein, we performed a meta-analysis aimed at comparing the risk of certain GI toxicities in mRCC patients treated with immuno-TKI combinations versus sunitinib monotherapy. Overall, four phase III trials (KEYNOTE-426, JAVELIN Renal 101, CheckMate 9ER, CLEAR) involving 3059 mRCC patients were available.

RESULTS

The meta-analysis suggested an increased risk of all-grade diarrhea, grade 3-4 diarrhea and grade 3-4 decreased appetite in patients treated with immuno-TKI combinations. Conversely, an apparently higher risk of all-grade nausea was observed in the sunitinib group.

CONCLUSION

The meta-analysis suggested that immuno-TKI combinations are associated with higher risk of GI toxicities compared with sunitinib. Beyond the efficacy of immuno-TKI combinations in mRCC patients, careful consideration should be given to treatment-related adverse events, including GI toxicities. Early recognition and treatment are critical to maximize recovery.

Sunitinib with photoirradiation-mediated reactive oxygen species generation induces apoptosis of renal cell carcinoma cells

BACKGROUND

Photodynamic therapy is a clinically approved, minimally invasive,therapeutic procedure used for the treatment of several cancers. In recent years, sunitinib, one of the tyrosine kinase inhibitors, has also attracted attention as a novel photosensitizer. However, there is currently no data available on the combined cytotoxic effects of sunitinib and photoirradiation on renal cell carcinoma including how the treatment induced cellular toxicity.

METHODS

In the present study, we used sunitinib as a photosensitizer and evaluated the effects of sunitinib and photodynamic therapy treatment on renal cancer cell lines, including the induction of cell death.

RESULTS

Our study showed that treatment with sunitinib and photoirradiation at 8 mW/cm² for 30 min resulted in the production intracellular reactive oxygen species (ROS), which is indicated by the increase in mRNA expression levels of PAI-1, NF-κβ, and Caspase-3. An increase in rate of apoptotic reaction and increase in the expression level of apoptotic marker were also observed when cells undergo treatment with sunitinib and photoirradiation.

CONCLUSIONS

Our findings suggest that combining photodynamic therapy with sunitinib represents a minimally invasive therapeutic procedure with cancer selectivity for renal cell carcinoma.

Interventional Treatment for Cholangiocarcinoma

Cholangiocarcinoma (CCA) is the second most common type of primary liver malignancy. The latest classification includes intrahepatic cholangiocarcinoma and extrahepatic cholangiocarcinoma, with the latter one further categorized into perihilar and distal cholangiocarcinoma. Although surgical resection is the preferred treatment for CCA, less than half of the patients are actually eligible for radical surgical resection. Interventional treatment, such as intra-arterial therapies, ablation, and brachytherapy (iodine-125 seed implantation), has become an acceptable palliative treatment for patients with unresectable CCA. For these patients, interventional treatment is helpful for locoregional control, symptom relief, and improving quality of life. Herein, in a timely and topical manner, we will review these advances and highlight future directions of research in this article.

Pembrolizumab for the treatment of renal cell carcinoma

INTRODUCTION

The acquisition of resistance to VEGF-inhibiting therapies has prompted research toward immunotherapy for the treatment of metastatic renal cell carcinoma (mRCC). Among several, checkpoint inhibitors including PD-1 and PD-L1 inhibitors are the most promising approach.

AREAS COVERED

This review addresses the clinical efficacy of the anti-PD-1 monoclonal antibody pembrolizumab in first- and second-line treatment for mRCC regarding the most recent and significant published and ongoing studies. Attention is also given to its pharmacological characteristics as well as adverse events and its impact on patients' quality of life.

EXPERT OPINION

Immunotherapy has become the backbone for the treatment of advanced RCC. With the approval of several therapeutic options, research needs now to focus on defining the appropriate therapy for each patient. Axitinib plus pembrolizumab belongs to the combinations of tyrosine kinase inhibitors (TKI) plus immune checkpoint inhibitors for the first-line treatment of metastatic RCC. New combinations of pembrolizumab plus TKI for the evaluation in first- and second-line treatment of mRCC available. However, studies directly comparing the various treatment regimens using predictive biomarkers and long-term endpoints, including treatment-free survival, are lacking.

Landscape of immune cell infiltration in clear cell renal cell carcinoma to aid immunotherapy

The tumor microenvironment, comprised of tumor cells and tumor-infiltrating immune cells, is closely associated with the clinical outcome of clear cell renal cell carcinoma (ccRCC) patients. However, the landscape of immune infiltration in ccRCC has not been fully elucidated. Herein, we applied multiple computational methods and various datasets to reveal the immune infiltrative landscape of ccRCC patients. The tumor immune infiltration (TII) levels of 525 ccRCC patients using a single-sample gene were examined and further categorized into immune infiltration subgroups. The TII score was characterized by distinct clinical traits and showed a significant divergence based on gender, grade, and stage. A high TII score was associated with the ERBB signaling pathway, the TGF-β signaling pathway, and the MTOR signaling pathway, as well as a better prognosis. Furthermore, patients with high TII scores exhibited greater sensitivity to pazopanib. The low TII score was characterized by a high immune infiltration level of CD8+ T cells, T follicular helper cells, and regulatory T cells (Tregs). Moreover, the immune check point genes, including CTLA-4, LAG3, PD-1, and IDO1, presented a high expression level in the low TII score group. Patients in the high TII score group demonstrated significant therapeutic advantages and clinical benefits. The findings in this study have the potential to assist in the strategic design of immunotherapeutic treatments for ccRCC.

MK-6482 as a potential treatment for von Hippel-Lindau disease-associated clear cell renal cell carcinoma

INTRODUCTION

Von Hippel-Lindau (VHL) disease is an inherited autosomal dominant syndrome caused by a germline mutation and/or deletion of the VHL gene. Inappropriate hypoxia-inducible factor (HIF)-mediated transcription of proangiogenic and metabolic genes leads to the development of tumors and cysts in multiple organs. Surgery is a standard treatment for localized tumors with a risk of metastasis or organ dysfunction. Repeated surgeries cause substantial morbidity and have a major impact on quality of life. There is an urgent need to develop effective and safe systemic treatments for VHL disease manifestations. The small-molecule HIF 2 alpha inhibitor MK-6482 (belzutifan) has demonstrated significant efficacy in VHL disease related renal cell carcinomas, hemangioblastomas, and pancreatic neuroendocrine tumors while demonstrating an acceptable safety profile.

AREAS COVERED

This paper reviews the development of the HIF-2 alpha inhibitor, MK-6482, and discusses preliminary results of ongoing phase I/II studies in renal cell carcinoma (RCC) and VHL disease. An examination of ongoing clinical development of MK-6482 and perspectives on potential future developments and challenges are offered.

EXPERT OPINION

Because of its favorable safety profile, its clear efficacy in VHL disease, promising findings in sporadic, advanced RCC, and convenient oral formulation, MK-6482 is expected to become a leading treatment for VHL disease. Among other currently available oral agents, we believe that MK-6482 will be a preferred treatment for VHL-associated RCC.

Recent advances of immunotherapy for biliary tract cancer

Introduction: Biliary tract cancer (BTC) is a heterogeneous group of aggressive malignancies comprising intrahepatic cholangiocarcinoma, extrahepatic cholangiocarcinoma, gallbladder cancer, and ampulla of Vater cancer. Although recent years have witnessed the emergence of novel treatment targets, medical therapy remains a compelling challenge in these hepatobiliary malignancies. In order to provide more effective treatment options, immune checkpoint inhibitors (ICIs) are currently under investigation in advanced BTC, with controversial results reported so far.Areas covered: This review provides an overview regarding current scenario of ICIs and immune-based combinations in advanced BTC, where several novel treatments are currently being developed, some of which have suggested interesting efficacy in recent clinical trials. In addition, we provide a report of ongoing Phase I to III clinical trials assessing ICIs and new immunotherapeutic strategies for advanced BTC.Expert opinion: Although immunotherapy has revolutionized the treatment landscape of several hematological and solid tumors, the role of ICIs and immune-based combinations in advanced BTC is still unclear. Despite ICI monotherapy has reported limited efficacy in this setting, the durable responses observed in sporadic cases suggest that testing patients for MMR, MSI, TMB, and PD-L1 expression is warranted. Results of currently ongoing trials are highly awaited.

Comparative effectiveness of first-line immune checkpoint inhibitors plus tyrosine kinase inhibitors according to IMDC risk groups in metastatic renal cell carcinoma: a meta-analysis

Aim: Immune checkpoint inhibitor (ICI)-based combinations have become the new standard of primary systemic treatment for metastatic renal cell carcinoma patients. We performed a meta-analysis aimed at evaluating ICIs plus tyrosine kinase inhibitors (TKIs) combinations across International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) risk groups. Materials & methods: All the relevant randomized clinical trials were retrieved through Cochrane library, PubMed/Med and EMBASE; three Phase III randomized clinical trials were included. Results: ICI-TKI combinations significantly decreased the risk of death in IMDC poor- and intermediate-risk patients. Conversely, a nonstatistically significant benefit was observed in favorable-risk patients. Conclusion: Our results suggest that IMDC poor-risk patients benefit most from ICI-TKI combinations, while a proportion of metastatic renal cell carcinoma patients could respond to targeted agent monotherapy.

Quality of life assessment in renal cell carcinoma Phase II and III clinical trials published between 2010 and 2020: a systematic review

Aims: Quality of life (QoL) assessment is frequently not included among the end points of clinical trials (CTs) on renal cell carcinoma. Herein we aimed to describe the assessment and reporting of QoL in Phase II and Phase III CTs published between 2010 and 2020. Methods: A total of 25 CTs were included; 76% of trials included were conducted in metastatic renal cell carcinoma patients, while 20% of studies evaluated adjuvant systemic treatments. Results: In 13/25 publications, QoL was not listed among the end points, with secondary publications dedicated to QoL present in a minority of cases. Conclusions: QoL was not included among the end points of a large percentage of CTs. Implementing the inclusion of QoL represents an urgent need.

Immunotherapy Is Associated with a Survival Benefit in Patients Receiving Chemotherapy for Metastatic Pancreatic Cancer

Background: Immunotherapy (IT) has led to improved survival in several common cancers but success in pancreatic ductal adenocarcinoma (PDAC) has been limited. We analyzed if combination IT-chemotherapy (IT-CT) is associated with improved survival compared with chemotherapy alone (CT) in patients with metastatic PDAC. Methods: The National Cancer Database (2004-2016) was queried for patients who were diagnosed with metastatic PDAC. Patients were categorized by treatment group: CT only and IT-CT. Patients were excluded if they received radiation or a surgical procedure. The primary outcome was overall survival. Results: A total of 59,289 patients were identified, of whom 58,947 (99.4%) received CT and 342 (0.6%) received IT-CT. The IT-CT group was younger, had fewer comorbidities, and was more often treated at an academic center. The utilization of multiagent CT was similar between the groups. Median survival of patients treated with IT-CT was longer than CT alone (7.9 months vs. 6.3 months, p = 0.005). On multivariable analysis, receipt of IT-CT was associated with a survival advantage as compared with CT (hazard ratio = 0.86, 95% confidence intervals 0.76-0.97) when adjusting for demographics and type of CT regimen. Conclusion: In patients with metastatic PDAC, it appears that combination IT-CT may perhaps be associated with a survival advantage compared with CT alone.

Determinants of treatment for first-line immune-based combinations in metastatic renal cell carcinoma: a critical overview of recent evidence

The last three decades have witnessed a revolution in the therapeutic scenario of metastatic renal cell carcinoma (mRCC), due to the advent of novel agents including tyrosine kinase inhibitors, immune checkpoint inhibitors and the combination of both treatments. These strategies have reported unprecedented response rates, thus improving the clinical outcomes of mRCC patients, and current international guidelines support the use of immune-based combinations as first-line treatment in patients with metastatic disease. However, more data are awaited to help clinicians in the decision-making process. Herein, we provide an overview of recently published results regarding immune-based combinations as first-line treatment in mRCC patients, critically discussing available data that could help in suggesting determinants of treatment in this setting.

A potent and selective PARP14 inhibitor decreases protumor macrophage gene expression and elicits inflammatory responses in tumor explants

PARP14 has been implicated by genetic knockout studies to promote protumor macrophage polarization and suppress the antitumor inflammatory response due to its role in modulating interleukin-4 (IL-4) and interferon-γ signaling pathways. Here, we describe structure-based design efforts leading to the discovery of a potent and highly selective PARP14 chemical probe. RBN012759 inhibits PARP14 with a biochemical half-maximal inhibitory concentration of 0.003 μM, exhibits >300-fold selectivity over all PARP family members, and its profile enables further study of PARP14 biology and disease association both in vitro and in vivo. Inhibition of PARP14 with RBN012759 reverses IL-4-driven protumor gene expression in macrophages and induces an inflammatory mRNA signature similar to that induced by immune checkpoint inhibitor therapy in primary human tumor explants. These data support an immune suppressive role of PARP14 in tumors and suggest potential utility of PARP14 inhibitors in the treatment of cancer.

Adjuvant therapy in renal cell carcinoma: is it the right strategy to inhibit VEGF?

Despite several clinical trials have assessed different agents in the adjuvant setting, renal cell carcinoma (RCC) still remains a disease orphan of an effective adjuvant treatment. In fact, systemic therapies targeting angiogenesis that have been observed to be effective in metastatic setting failed to show an improvement in terms of clinical outcomes when used ad adjuvant treatments. In this study, we performed a meta-analysis of 5 randomized clinical trials to assess the impact of tyrosine kinase inhibitors (TKIs) targeting angiogenesis after surgery: ASSURE, S-TRAC, PROTECT, ATLAS, SORCE. Among the 6,531 patients assessed, we confirmed the lack of efficacy of adjuvant treatments in terms of disease-free survival (DFS) (pooled-HR 0.93, 95% CI, 0.84–1.02, P=0.16) and overall survival (OS) (pooled-HR 0.98, 95% CI, 0.88–1.09, P=0.54). To the best of our knowledge, we still ignore why some treatments active in the metastatic setting do not show similar efficacy as adjuvant treatment. Exploring possible reasons of this apparently conflicting results is important as it may offer new insights that should be evaluated in next generation adjuvant trials. Immune checkpoint inhibitors (ICIs) have reported significant results—as monotherapy or in combinations with other anticancer agents—in metastatic setting, and the results of trials evaluating these agents in the adjuvant setting are awaited.

Combination of immune checkpoint inhibitors and tyrosine kinase inhibitors for the treatment of renal cell carcinoma

INTRODUCTION

We have experienced several paradigm shifts and substantial changes in the treatment of metastatic renal cell carcinoma (mRCC) over the last two decades. Combination therapy with immune checkpoint inhibitors (ICI) as a dual combination (ICI-ICI) or with VEGFR-tyrosine kinase inhibitors (VEGF-TKI) has shown remarkable efficacy in mRCC patients and has become the standard of care in first-line therapy.

AREAS COVERED

In this review, we will discuss the background as well as the benefits of combining ICI with TKI compared to ICI-ICI combination therapy for mRCC treatment and will also briefly highlight biomarkers for patient selection on therapies to improve patient outcomes and limit toxicities.

EXPERT OPINION

Due to the mediated additional anti-tumor effects, there is a strong rationale to combine ICIs and TKIs for mRCC therapy. When comparing first-line therapy options, the exceptionally higher ORR and PFS for the ICI-TKI combinations should be highlighted, whereas, nevertheless, the complete response rate is slightly higher for the ICI-ICI combination. In terms of an individualized therapeutic approach, biomarkers predicting the success or failure of an anti-VEGF-based regimen or ICI therapy as a corresponding mono - or combination therapy are lacking so far, however, gene expression signatures can be a landmark in this field.

Clinical efficacy of immune checkpoint inhibitors in patients with brain metastases

Brain metastases (BMs) represent a negative prognostic factor for patients with solid malignancies. BMs are generally approached with loco-regional treatments and the blood-brain barrier limits the efficacy of some systemic drugs. The aim of this review is to summarize current knowledge about the role of immune checkpoint inhibitors for the management of brain metastases in patients with solid malignancies. We performed a review of available literature. Immune checkpoint inhibitors represent the standard treatment for several advanced solid malignancies. However, with the exception of melanoma their clinical role in other solid malignancies is not completely clear due to the exclusion of patients with BM from approval clinical trials. Immune-checkpoint inhibitors may be an effective treatment of brain metastases of melanoma while their clinical role on brain metastases from other solid malignancies is uncertain.

The Role of Chemokine Receptor CXCR3 and Its Ligands in Renal Cell Carcinoma

The major invasive subtype of kidney cancer is renal cell carcinoma (RCC). The essential components of cancer development are chronic inflammation and neoangiogenesis. It has been suggested that the chemokine ligand 9, -10, –11 (CXCL9–11) and chemokine receptor 3 (CXCR3) chemokines receptor expressed on monocytes, T and NK cells may be involved in the inhibition of angiogenesis. However, to date, little is known about the potential clinical significance of these chemokines and their receptor in renal cell carcinoma. Therefore, in this review, we described the role of CXCR3 and its ligands in pathogenesis of RCC. We performed an extensive search of the current literature in our investigation, using the MEDLINE/PubMed database. The changes of chemokines and their specific receptor in renal cell carcinoma were observed. Published studies revealed an increased expression of CXCR3 and elevated concentration of its ligands in RCC. The association between treatment of RCC and CXCL9–11/CXCR3 concentration and expression was also observed. Moreover, CXCR3 and its ligands levels were related to patient’s prognosis, risk of metastasis and tumor growth. This review describes the potential role of CXCR3 and its ligands in pathogenesis of RCC, as well as their potential immune-therapeutic significance. However, future studies should aim to confirm the clinical and prognostic role of CXCL9–11/CXCR3 in renal cell carcinoma.

Normalized Dual-Energy Iodine Ratio Best Differentiates Renal Cell Carcinoma Subtypes Among Quantitative Imaging Biomarkers From Perfusion CT and Dual-Energy CT

OBJECTIVE. The objective of our study was to assess and compare the diagnostic accuracy of perfusion CT (PCT) and dual-energy CT (DECT) in differentiating clear cell renal cell carcinoma (ccRCC) from non-ccRCC. MATERIALS AND METHODS. This retrospective study included 51 patients with 52 renal cell carcinomas (RCCs) (36 ccRCCs and 16 non-ccRCCs) who underwent both PCT and DECT before surgery or biopsy between January 2014 and December 2018. Three independent readers measured blood flow, blood volume (BV), and permeability using PCT and iodine concentration (IC) and iodine ratio using DECT. Interreader agreement was calculated using the intraclass correlation coefficient (ICC). Multivariable logistic regression analysis was performed to assess PCT and DECT models. Size-specific dose estimates of the two methods were compared. RESULTS. BV (ICC, 0.93) and iodine ratio (ICC, 0.85) were the most reproducible parameters. Both PCT and DECT were significant models (p < 0.05, all readers) for differentiating ccRCC from non-ccRCC. There was no significant difference in diagnostic accuracy between PCT and DECT (p > 0.05). BV and iodine ratio were independent predictors of nonccRCC (p < 0.05). However, the mean size-specific dose estimate was 16 times lower with DECT than with PCT (p < 0.001). The AUC of iodine ratio was 0.95, and sensitivity, specificity, and accuracy with an iodine ratio cutoff of 63.72% was 0.90, 0.86, and 0.87, respectively. CONCLUSION. PCT and DECT had comparable and high diagnostic accuracy in differentiating RCC subtypes; however, because of the significantly lower radiation dose of DECT, iodine ratio may be used as the best independent predictor.

Correlative serum biomarker analyses in the phase 2 trial of lenvatinib-plus-everolimus in patients with metastatic renal cell carcinoma

Background

No biomarkers have been established to predict treatment efficacy in renal cell carcinoma (RCC). In an exploratory retrospective analysis of a Phase 2 study, we constructed composite biomarker scores (CBSs) to predict progression-free survival (PFS) and overall survival (OS) in patients with metastatic RCC randomised to receive lenvatinib-plus-everolimus.

Methods

Of 40 biomarkers tested, the 5 most strongly associated with PFS (HGF, MIG, IL-18BP, IL-18, ANG-2) or OS (TIMP-1, M-CSF, IL-18BP, ANG-2, VEGF) were used to make a 5-factor PFS-CBS or OS-CBS, respectively. A 2-factor CBS was generated with biomarkers common to PFS-CBS and OS-CBS. Patients were divided into groups accordingly (5-factor-CBS high: 3−5, CBS-low: 0–2; 2-factor-CBS high: 1–2, CBS-low: 0).

Results

PFS/OS with lenvatinib-plus-everolimus were significantly longer in the 5-factor CBS-high group versus the CBS-low group (P = 0.0022/P < 0.0001, respectively). In the CBS-high group, PFS/OS were significantly longer with lenvatinib-plus-everolimus versus everolimus (P < 0.001/P = 0.0079, respectively); PFS was also significantly longer with lenvatinib-plus-everolimus versus lenvatinib (P = 0.0046). The 5-factor-CBS had a predictive role in PFS and OS after multivariate analysis. Similar trends were observed with the 2-factor-CBS for PFS (i.e., lenvatinib-plus-everolimus versus everolimus).

Conclusions

The 5-factor CBS may identify patients with metastatic RCC who would benefit from lenvatinib-plus-everolimus versus everolimus; additional validation is required.

Clinical trial registration

The clinical trial registration number is NCT01136733.

Designing novel immunocombinations in metastatic renal cell carcinoma

Immune checkpoint inhibitors have radically changed the treatment approach to metastatic renal cell carcinoma (mRCC). In the present article, we reported and discussed the available data with immunocombinations in mRCC, offering new perspectives in the treatment landscape of these patients. We discussed the main results of pivotal clinical trials of immune checkpoint inhibitors in the treatment of mRCC. Moreover, we discussed novel immuno-based treatments currently under investigation in ongoing clinical trials. Renal cell carcinoma is a particularly immunogenic tumor and immunotherapy is a pivotal treatment approach. A wide series of clinical trials is exploring novel promising immunocombinations in patients with renal cell carcinoma.

Combination drug regimens for metastatic clear cell renal cell carcinoma

Renal cell carcinomas (RCC) make up about 90% of kidney cancers, of which 80% are of the clear cell subtype. About 20% of patients are already metastatic at the time of diagnosis. Initial treatment is often cytoreductive nephrectomy, but systemic therapy is required for advanced RCC. Single agent targeted therapies are moderately toxic and only somewhat effective, leading to development of immunotherapies and combination therapies. This review identifies limitations of monotherapies for metastatic renal cell carcinoma, discusses recent advances in combination therapies, and highlights therapeutic options under development. The goal behind combining various modalities of systemic therapy is to potentiate a synergistic antitumor effect. However, combining targeted therapies may cause increased toxicity. The initial attempts to create therapeutic combinations based on inhibition of the vascular endothelial growth factor or mammalian target of rapamycin pathways were largely unsuccessful in achieving a profile of increased synergy without increased toxicity. To date, five combination therapies have been approved by the U.S. Food and Drug Administration, with the most recently approved therapies being a combination of checkpoint inhibition plus targeted therapy. Several other combination therapies are under development, including some in the phase 3 stage. The new wave of combination therapies for metastatic RCC has the potential to increase response rates and improve survival outcomes while maintaining tolerable side effect profiles.

High-dimensional Cytometry (ExCYT) and Mass Spectrometry of Myeloid Infiltrate in Clinically Localized Clear Cell Renal Cell Carcinoma Identifies Novel Potential Myeloid Targets for Immunotherapy

Although the focus of the role of cancer immunotherapy has been in advanced disease states, we sought to investigate changes to the immune infiltrate of early, clinically localized clear cell Renal Cell Carcinoma (ccRCC). Using orthogonal approaches including Mass Spectrometry on immune cell infiltrates, we report numerous alterations that provide new insight into the biology of treatment-naïve ccRCC and identification of novel targets that may prove to be clinically impactful.

Renal Cell Carcinoma (RCC) is one of the most commonly diagnosed cancers worldwide with research efforts dramatically improving understanding of the biology of the disease. To investigate the role of the immune system in treatment-naïve clear cell Renal Cell Carcinoma (ccRCC), we interrogated the immune infiltrate in patient-matched ccRCC tumor samples, benign normal adjacent tissue (NAT) and peripheral blood mononuclear cells (PBMCs isolated from whole blood, focusing our attention on the myeloid cell infiltrate. Using flow cytometric, MS, and ExCYT analysis, we discovered unique myeloid populations in PBMCs across patient samples. Furthermore, normal adjacent tissues and ccRCC tissues contained numerous myeloid populations with a unique signature for both tissues. Enrichment of the immune cell (CD45⁺) fraction and subsequent gene expression analysis revealed a number of myeloid-related genes that were differentially expressed. These data provide evidence, for the first time, of an immunosuppressive and pro-tumorigenic role of myeloid cells in early, clinically localized ccRCC. The identification of a number of immune proteins for therapeutic targeting provides a rationale for investigation into the potential efficacy of earlier intervention with single-agent or combination immunotherapy for ccRCC.

The combination of artificial intelligence and systems biology for intelligent vaccine design

INTRODUCTION

A new body of evidence depicts the applications of artificial intelligence and systems biology in vaccine design and development. The combination of both approaches shall revolutionize healthcare, accelerating clinical trial processes and reducing the costs and time involved in drug research and development.

AREAS COVERED

This review explores the basics of artificial intelligence and systems biology approaches in the vaccine development pipeline. The topics include a detailed description of epitope prediction tools for designing epitope-based vaccines and agent-based models for immune system response prediction, along with a focus on their potentiality to facilitate clinical trial phases.

EXPERT OPINION

Artificial intelligence and systems biology offer the opportunity to avoid the inefficiencies and failures that arise in the classical vaccine development pipeline. One promising solution is the combination of both methodologies in a multiscale perspective through an accurate pipeline. We are entering an 'in silico era' in which scientific partnerships, including a more and more increasing creation of an 'ecosystem' of collaboration and multidisciplinary approach, are relevant for addressing the long and risky road of vaccine discovery and development. In this context, regulatory guidance should be developed to qualify the in silico trials as evidence for intelligent vaccine development.

Comparative Efficacy of First-Line Immune-Based Combination Therapies in Metastatic Renal Cell Carcinoma: A Systematic Review and Network Meta-Analysis

Three drug combinations, ipilimumab-nivolumab (Ipi-Nivo), pembrolizumab-axitinib (Pembro-Axi), and avelumab-axitinib (Ave-Axi), have received regulatory approval in the USA and Europe for the treatment of metastatic renal cell carcinoma with clear cell component (mRCC). However, no head-to-head comparison data are available to identify the best option. Therefore, we aimed to compare these new treatments in a first-line setting. We conducted a systematic search in PubMed, the Cochrane Library, and clinicaltrials.gov for any randomized controlled trials of treatment-naïve patients with mRCC, from January 2015 to October 2019. The process was performed according to PRISMA guidelines. We performed a Bayesian network meta-analysis with two different approaches, a contrast-based model comparing HRs and ORs between studies and arm-based using parametric modeling. The outcomes for the analysis were overall survival, progression-free survival (PFS), and objective response rate. Our search identified 3 published phase 3 randomized clinical trials (2835 patients). In the contrast-based model, Ave-Axi (SUCRA = 83%) and Pembro-Axi (SUCRA = 80%) exhibited the best ranking probabilities for PFS. For overall survival (OS), Pembro-Axi (SUCRA = 96%) was the most preferable option against Ave-Axi and Ipi-Nivo. Objective response rate analysis showed Ave-Axi as the best (SUCRA: 94%) and Pembro-Axi as the second best option. In the parametric models, the risk of progression was comparable for Ave-Axi and Ipi-Nivo, whereas Pembro-Axi exhibited a lower risk during the first 6 months of treatment and a higher risk afterwards. Furthermore, Pembro-Axi exhibited a net advantage in terms of OS over the two other regimens, while Ave-Axi was the least preferable option. Overall evidence suggests that pembrolizumab plus axitinib seems to have a slight advantage over the other two combinations.

A Meta-Analysis Evaluating Clinical Outcomes of Patients with Renal Cell Carcinoma Harboring Chromosome 9P Loss

CONTEXT

9p loss appears a reliable and promising marker able to differentiate specific categories of patients with renal cell carcinoma associated with a worse prognosis.

OBJECTIVE

The aim was to systematically evaluate relative risk of death, cancer-specific survival (CSS) and disease-free survival (DFS) among patients harboring 9p loss.

EVIDENCE SYNTHESIS

We found a total of 92 potentially relevant articles focused on the detection of 9p loss in patients with renal cell carcinoma and clinical outcomes of this population. Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines were employed to carry out this work. Fourteen studies resulted to be eligible for this analysis; 11 of these reported data on 5-year overall survival, six on CSS and four on DFS. An increased risk of death has been observed in patients harboring 9p loss (pooled relative risk of 3.965; 95% confidence interval [CI] 2.647-5.940, p < 0.001). Similarly, worse CSS (hazard ratio [HR] 6.776; 95% CI 3.824-12.009; p < 0.001) and DFS (HR 2.914; 95% CI 1.245-6.819; p = 0.014) have been observed in this population. Heterogeneity was significant in survival analysis, while no significant heterogeneity was observed in the CSS and DFS analyses.

CONCLUSIONS

Patients harboring chromosome 9p loss have worse clinical outcomes in terms of overall survival, CSS and DFS.

CREB1 is affected by the microRNAs miR-22-3p, miR-26a-5p, miR-27a-3p, and miR-221-3p and correlates with adverse clinicopathological features in renal cell carcinoma

The transcription factor cAMP response element-binding protein (CREB1) has been shown to be involved in diverse biological pathways including the regulation of cell proliferation, apoptosis, cell cycle progression, and metastasis. In this context, aberrant expression of CREB1 and the functional consequences are well investigated in a number of hematopoietic and solid tumors. However, CREB1 expression and underlying control mechanisms are only poorly analyzed in renal cell carcinoma (RCC). The present study confirmed a deregulation of CREB1 protein in the clear cell type of RCC (ccRCC) and analysis of in-house ccRCC cell lines suggested a post-transcriptional control. The combination of miRNA enrichment assay, in silico analysis and molecular biological approaches revealed four novel CREB1-regulating miRNAs, namely miR-22-3p, miR-26a-5p, miR-27a-3p, and miR-221-3p. Categorizing RCC samples as CREB1 negative or positive, respectively, the expression of these miRNAs was found to be inversely correlated with CREB1 protein levels. Analyzing 453 consecutive RCC tumors by immunohistochemistry, weakly negative, but significant correlations of CREB1 with tumor stage and grade, vascular invasion (V1) and lymphovascular invasion (L1) were found. In this respect, ccRCC might differ from other solid tumors like esophageal squamous-cell carcinoma or glioma.

Stem/progenitor cell marker expression in clear cell renal cell carcinoma: a potential relationship with the immune microenvironment to be explored

BACKGROUND

Clear cell renal cell carcinoma (ccRCC) is a markedly heterogeneous disease in many aspects, including the tumour microenvironment. Our previous study showed the importance of the tumour microenvironment in ccRCC xeno-transplant success rates. In order to better understand the potential relationship between TICs and the immune microenvironment, we employed a multi-modal approach, examining RNA and protein expression (flow cytometry, immunohistochemistry).

METHODS

We first examined the gene expression pattern of 18 stem/progenitor marker genes in the cancer genome atlas (TCGA) ccRCC cohort. Flow cytometry was next employed to examine lineage-specific expression levels of stem/progenitor markers and immune population makeup in six, disaggregated, primary ccRCC specimens. Immunohistochemistry was performed on a commercial ccRCC tissue microarray (TMA).

RESULTS

The 18 genes differed with respect to their correlation patterns with one another and to their prognostic significance. By flow cytometry, correlating expression frequency of 12 stem/progenitor markers and CD10 resulted in two clusters-one with CD10 (marker of proximal tubular differentiation), and second cluster containing mostly mesenchymal stem cell (MSC) markers, including CD146. In turn, these clusters differed with respect to their correlation with different CD45+ lineage markers and their expression of immune checkpoint pathway proteins. To confirm these findings, four stem/progenitor marker expression patterns were compared with CD4, CD8 and CD20 in a ccRCC TMA which showed a number of similar trends with respect to frequency of the different tumour-infiltrating leukocytes.

CONCLUSION

Taken together, we observed heterogeneous but patterned expression levels of different stem/progenitor markers. Our results suggest a non-random relationship between their expression patterns with the immune microenvironment populations in ccRCC.

Modeling clear cell renal cell carcinoma and therapeutic implications

Renal cell carcinoma (RCC) comprises a diverse group of malignancies arising from the nephron. The most prevalent type, clear cell renal cell carcinoma (ccRCC), is characterized by genetic mutations in factors governing the hypoxia signaling pathway, resulting in metabolic dysregulation, heightened angiogenesis, intratumoral heterogeneity, and deleterious tumor microenvironmental (TME) crosstalk. Identification of specific genetic variances has led to therapeutic innovation and improved survival for patients with ccRCC. Current barriers to effective long-term therapeutic success highlight the need for continued drug development using improved modeling systems. ccRCC preclinical models can be grouped into three broad categories: cell line, mouse, and 3D models. Yet, the breadth of important unanswered questions in ccRCC research far exceeds the accessibility of model systems capable of carrying them out. Accordingly, we review the strengths, weaknesses, and therapeutic implications of each model system that are relied upon today.

Pancreatic ductal adenocarcinoma: Treatment hurdles, tumor microenvironment and immunotherapy

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal diseases, with an average 5-year survival rate of less than 10%. Unfortunately, the majority of patients have unresectable, locally advanced, or metastatic disease at the time of diagnosis. Moreover, traditional treatments such as chemotherapy, surgery, and radiation have not been shown to significantly improve survival. Recently, there has been a swift increase in cancer treatments that incorporate immunotherapy-based strategies to target all the stepwise events required for tumor initiation and progression. The results in melanoma, non-small-cell lung cancer and renal cell carcinoma are very encouraging. Unfortunately, the application of checkpoint inhibitors, including anti-CTLA4, anti-PD-1, and anti-PD-L1 antibodies, in pancreatic cancer has been disappointing. Many studies have revealed that the PDAC microenvironment supports tumor growth, promotes metastasis and consists of a physical barrier to drug delivery. Combination therapies hold great promise for enhancing immune responses to achieve a better therapeutic effect. In this review, we provide an outline of why pancreatic cancer is so lethal and of the treatment hurdles that exist. Particular emphasis is given to the role of the tumor microenvironment, and some of the latest and most promising studies on immunotherapy in PDAC are also presented.

Targeting the Immune system and Epigenetic Landscape of Urological Tumors

In the last years, we have witnessed remarkable advances in targeted therapies for cancer patients. There is a growing effort to either replace or reduce the dose of unspecific, systemic (chemo)therapies, given the associated short- and long-term side effects, by introducing more specific targeted therapies as single or combination agents. Due to the well-known implications of the immune system and epigenetic landscape in modulating cancer development, both have been explored as potential targets in several malignancies, including those affecting the genitourinary tract. As the immune system function is also epigenetically regulated, there is rationale for combining both strategies. However, this is still rather underexplored, namely in urological tumors. We aim to briefly review the use of immune therapies in prostate, kidney, bladder, and testicular cancer, and further describe studies providing supporting evidence on their combination with epigenetic-based therapies.

Exceptional Response of Metastatic Chromophobe Renal Cell Carcinoma to Vascular Endothelial Growth Factor (VEGF) Inhibitors: Should Increased VEGF-C Expression Be Used to Guide Treatment?

There is sparse literature demonstrating effective treatments for metastatic chromophobe renal cell carcinoma (ChRCC). The tyrosine kinase inhibitor (TKI) sunitinib selectively inhibits the VEGF pathway and it is a standard care for metastatic clear cell renal cell carcinoma (ccRCC), although data supporting its use in ChRCC is much more limited. A 56-year-old underwent palliative nephrectomy for locally-advanced ChRCC with sarcomatoid differentiation. Tumor gene expression profiling using Affymetrix HG-U133 Plus 2.0 GeneChip platform demonstrated significantly elevated VEGF-C expression compared to normal renal tissue (n = 12) and other types RCC (n = 158). Adjuvant sunitinib was used to treat his residual unresectable retroperitoneal lymph nodes. He demonstrated an exceptional response and underwent complete surgical resection four months later. He has been managed with TKIs for nearly nine years with only minimal disease progression. Additional studies exploring treatment options for patients with non-clear cell RCC are needed; in their absence, we would recommend TKIs for patients whose tumors bear a similar molecular profile.

Genitourinary Tumors: Update on Molecular Biomarkers for Diagnosis, Prognosis and Prediction of Response to Therapy

BACKGROUND

Research of biomarkers in genitourinary tumors goes along with the development of complex emerging techniques ranging from next generation sequencing platforms, applied to archival pathology specimens, cytological samples, liquid biopsies, and to patient-derived tumor models.

METHODS

This contribution is an update on molecular biomarkers for diagnosis, prognosis and prediction of response to therapy in genitourinary tumors. The following major topics are dealt with: Immunological biomarkers, including the microbiome, and their potential role and caveats in renal cell carcinoma, bladder and prostate cancers and testicular germ cell tumors; Tissue biomarkers for imaging and therapy, with emphasis on Prostate-specific membrane antigen in prostate cancer; Liquid biomarkers in prostate cancer, including circulating tumor cell isolation and characterization in renal cell carcinoma, bladder cancer with emphasis on biomarkers detectable in the urine and testicular germ cell tumors; and Biomarkers and economic sustainability.

CONCLUSION

The identification of effective biomarkers has become a major focus in cancer research, mainly due to the necessity of selecting potentially responsive patients in order to improve their outcomes, as well as to reduce the toxicity and costs related to ineffective treatments.

The challenges of adoptive cell transfer in the treatment of human renal cell carcinoma

Renal cell carcinoma (RCC) is one of the most lethal urologic malignancies. Its incidence continues to rise worldwide with a rate of 2% per year. Approximately, one-third of the RCC patients are diagnosed at advanced stages due to the asymptomatic nature of its early stages. This represents a great hurdle, since RCC is largely chemoresistant/radioresistant, and targeted therapy of mRCC still has limited efficacy. The 5-year survival rate of metastatic RCC (mRCC) is only around 10%. Adoptive cell transfer (ACT), a particular form of cell-based anticancer immunotherapy, is a promising approach in the treatment of mRCC. The vaccination principle, however, faces unique challenges that preclude the efficacy of ACT. In this article, we review the main challenges of ACT in the treatment of mRCC and describe multiple methods that can be used to overcome these challenges. In this respect, the ultimate purpose of this review is to provide a descriptive tool by which to improve the development of novel protocols for ACT of mRCC.