Crizotinib achieves long-lasting disease control in advanced papillary renal-cell carcinoma type 1 patients with MET mutations or amplification. EORTC 90101 CREATE trial

Genomic profiling and molecular characterization of non-clear cell renal cell carcinoma: a narrative review from a clinical perspective

While the clear-cell renal cell carcinoma (ccRCC) treatment has undergone several paradigm shifts in recent years, the non-clear cell renal cell carcinoma (nccRCC) therapeutic approach has yet to be extensively investigated and improved. The WHO 2022 classification of renal neoplasms redefined the most common nccRCC subtypes (papillary and chromophobe RCC) and introduced the molecularly defined RCC class, which is a first step in the direction of better molecular profiling of nccRCC. We reviewed the literature data on known genomic alterations of clinical interest in nccRCC and discussed their potential role in guiding therapeutic choices in each nccRCC entity. Among the alterations discussed, we focused on the ones that could be treated with already available drugs, such as MET-driven papillary RCC, mechanistic target of rapamycin altered chromophobe RCC, anaplastic lymphoma kinase-rearranged RCC, and fumarate-hydratase deficient RCC. Furthermore, we focused on the currently ongoing clinical trials and further evidence for all the other entities, such as SMARCB1-deficient RCC, TFE3 and transcription factorEB (TFEB)-altered RCC, and Elongin C (ELOC)-mutated RCC. The vast heterogeneity of nccRCC does not allow a one-size-fits-all solution; therefore, molecular characterization is the path toward effective therapies and fully personalized medicine for these entities.

Systemic therapy for non-clear cell renal cell carcinomas: A systematic review

OBJECTIVE

Renal cell carcinoma (RCC) is the most common kidney cancer, with clear cell RCC being the predominant subtype. However, non-clear cell RCC constitutes a significant proportion of cases, presenting distinct challenges in treatment due to its varied histological subtypes. Despite recent advancements, the optimal therapeutic approach for non-clear cell RCC remains uncertain due to limited high-quality evidence. This systematic review aims to evaluate the efficacy of systemic therapies in nccRCC subgroups.

DATA SOURCE

A comprehensive literature search identified studies from 2010 to 2024, using PubMed and Clinicaltrials.gov databases focusing on clinical trials and treatment outcomes.

DATA SUMMARY

Results highlight the evolving therapeutic landscape, with targeted agents and immunotherapy demonstrating promising anti-tumor effects. Notably, tyrosine kinase inhibitors (TKIs) such as sunitinib and mTOR inhibitors like temsirolimus have shown efficacy across different subtypes. Combination therapies, including immunotherapy-based regimens, have also shown favorable outcomes. immune checkpoint inhibitors such as nivolumab and pembrolizumab demonstrated encouraging antitumor activity. Furthermore, specific targeting of signaling pathways, such as the c-MET pathway, has demonstrated efficacy in certain PapillaryRCC.

CONCLUSION

While combination therapies, including immunotherapies, have shown positive outcomes, immune checkpoint inhibitors like nivolumab and pembrolizumab have demonstrated encouraging antitumor activity. Additionally, targeting the c-MET pathway has proven effective in certain papillary RCC. Further research is warranted to establish optimal treatment strategies and improve outcomes for patients with non-clear cell RCC. Systemic therapy for non-clear cell RCC is complex and evolving. Further research is needed to delineate optimal treatment strategies for different histological subtypes and improve patient outcomes.

The MET Oncogene: An Update on Targeting Strategies

The MET receptor, commonly known as HGF (hepatocyte growth factor) receptor, is a focus of extensive scientific research. MET has been linked to embryonic development, tissue regeneration following injury, tumorigenesis, and cancer metastasis. These functions underscore its involvement in numerous cellular processes, including stemness, proliferation, motility, cell dissociation, and survival. However, the enigmatic nature of MET becomes apparent in the context of cancer. When MET remains persistently activated, since its gene undergoes genetic alterations, it initiates a complex signaling cascade setting in motion an aggressive and metastatic program that is characteristic of malignant cells and is known as "invasive growth". The expanding knowledge of MET signaling has opened up numerous opportunities for therapeutic interventions, particularly in the realm of oncology. Targeting MET presents a promising strategy for developing novel anti-cancer treatments. In this review, we provide an updated overview of drugs designed to modulate MET signaling, highlighting MET kinase inhibitors, degraders, anti-MET/HGF monoclonal antibodies, and MET-targeted antibody-drug conjugates. Through this review, we aim to contribute to the ongoing advancement of therapeutic strategies targeting MET signaling.

Recording and classifying MET receptor mutations in cancers

Tyrosine kinase inhibitors (TKI) directed against MET have been recently approved to treat advanced non-small cell lung cancer (NSCLC) harbouring activating MET mutations. This success is the consequence of a long characterization of MET mutations in cancers, which we propose to outline in this review. MET, a receptor tyrosine kinase (RTK), displays in a broad panel of cancers many deregulations liable to promote tumour progression. The first MET mutation was discovered in 1997, in hereditary papillary renal cancer (HPRC), providing the first direct link between MET mutations and cancer development. As in other RTKs, these mutations are located in the kinase domain, leading in most cases to ligand-independent MET activation. In 2014, novel MET mutations were identified in several advanced cancers, including lung cancers. These mutations alter splice sites of exon 14, causing in-frame exon 14 skipping and deletion of a regulatory domain. Because these mutations are not located in the kinase domain, they are original and their mode of action has yet to be fully elucidated. Less than five years after the discovery of such mutations, the efficacy of a MET TKI was evidenced in NSCLC patients displaying MET exon 14 skipping. Yet its use led to a resistance mechanism involving acquisition of novel and already characterized MET mutations. Furthermore, novel somatic MET mutations are constantly being discovered. The challenge is no longer to identify them but to characterize them in order to predict their transforming activity and their sensitivity or resistance to MET TKIs, in order to adapt treatment.

New clinical trial design in precision medicine: discovery, development and direction

In the era of precision medicine, it has been increasingly recognized that individuals with a certain disease are complex and different from each other. Due to the underestimation of the significant heterogeneity across participants in traditional "one-size-fits-all" trials, patient-centered trials that could provide optimal therapy customization to individuals with specific biomarkers were developed including the basket, umbrella, and platform trial designs under the master protocol framework. In recent years, the successive FDA approval of indications based on biomarker-guided master protocol designs has demonstrated that these new clinical trials are ushering in tremendous opportunities. Despite the rapid increase in the number of basket, umbrella, and platform trials, the current clinical and research understanding of these new trial designs, as compared with traditional trial designs, remains limited. The majority of the research focuses on methodologies, and there is a lack of in-depth insight concerning the underlying biological logic of these new clinical trial designs. Therefore, we provide this comprehensive review of the discovery and development of basket, umbrella, and platform trials and their underlying logic from the perspective of precision medicine. Meanwhile, we discuss future directions on the potential development of these new clinical design in view of the "Precision Pro", "Dynamic Precision", and "Intelligent Precision". This review would assist trial-related researchers to enhance the innovation and feasibility of clinical trial designs by expounding the underlying logic, which be essential to accelerate the progression of precision medicine.

Hereditary Renal Cancer Syndromes

Familial kidney tumors represent a rare variety of hereditary cancer syndromes, although systematic gene sequencing studies revealed that as many as 5% of renal cell carcinomas (RCCs) are associated with germline pathogenic variants (PVs). Most instances of RCC predisposition are attributed to the loss-of-function mutations in tumor suppressor genes, which drive the malignant progression via somatic inactivation of the remaining allele. These syndromes almost always have extrarenal manifestations, for example, von Hippel-Lindau (VHL) disease, fumarate hydratase tumor predisposition syndrome (FHTPS), Birt-Hogg-Dubé (BHD) syndrome, tuberous sclerosis (TS), etc. In contrast to the above conditions, hereditary papillary renal cell carcinoma syndrome (HPRCC) is caused by activating mutations in the MET oncogene and affects only the kidneys. Recent years have been characterized by remarkable progress in the development of targeted therapies for hereditary RCCs. The HIF2aplha inhibitor belzutifan demonstrated high clinical efficacy towards VHL-associated RCCs. mTOR downregulation provides significant benefits to patients with tuberous sclerosis. MET inhibitors hold promise for the treatment of HPRCC. Systematic gene sequencing studies have the potential to identify novel RCC-predisposing genes, especially when applied to yet unstudied populations.

A phase II trial of nivolumab followed by ipilimumab and nivolumab in advanced non-clear-cell renal cell carcinoma

OBJECTIVE

To evaluate the efficacy of sequential treatment with ipilimumab and nivolumab following progression on nivolumab monotherapy in individuals with advanced, non-clear-cell renal cell carcinoma (nccRCC).

MATERIALS AND METHODS

UNISoN (ANZUP1602; NCT03177239) was an open-label, single-arm, phase 2 clinical trial that recruited adults with immunotherapy-naïve, advanced nccRCC. Participants received nivolumab 240 mg i.v. two-weekly for up to 12 months (Part 1), followed by sequential addition of ipilimumab 1 mg/kg three-weekly for four doses to nivolumab if disease progression occurred during treatment (Part 2). The primary endpoint was objective tumour response rate (OTRR) and secondary endpoints included duration of response (DOR), progression-free (PFS) and overall survival (OS), and toxicity (treatment-related adverse events).

RESULTS

A total of 83 participants were eligible for Part 1, including people with papillary (37/83, 45%), chromophobe (15/83, 18%) and other nccRCC subtypes (31/83, 37%); 41 participants enrolled in Part 2. The median (range) follow-up was 22 (16-30) months. In Part 1, the OTRR was 16.9% (95% confidence interval [CI] 9.5-26.7), the median DOR was 20.7 months (95% CI 3.7-not reached) and the median PFS was 4.0 months (95% CI 3.6-7.4). Treatment-related adverse events were reported in 71% of participants; 19% were grade 3 or 4. For participants who enrolled in Part 2, the OTRR was 10%; the median DOR was 13.5 months (95% CI 4.8-19.7) and the median PFS 2.6 months (95% CI 2.2-3.8). Treatment-related adverse events occurred in 80% of these participants; 49% had grade 3, 4 or 5. The median OS was 24 months (95% CI 16-28) from time of enrolment in Part 1.

CONCLUSIONS

Nivolumab monotherapy had a modest effect overall, with a few participants experiencing a long DOR. Sequential combination immunotherapy by addition of ipilimumab in the context of disease progression to nivolumab in nccRCC is not supported by this study, with only a minority of participants benefiting from this strategy.

Monitoring phosphorylation and acetylation of CRISPR-mediated HiBiT-tagged endogenous proteins

Intracellular pathways transduce signals through changes in post-translational modifications (PTMs) of effector proteins. Among the approaches used to monitor PTM changes are immunoassays and overexpression of recombinant reporter genes. Genome editing by CRISPR/Cas9 provides a new means to monitor PTM changes by inserting reporters onto target endogenous genes while preserving native biology. Ideally, the reporter should be small in order not to interfere with the processes mediated by the target while sensitive enough to detect tightly expressed proteins. HiBiT is a 1.3 kDa reporter peptide capable of generating bioluminescence through complementation with LgBiT, an 18 kDa subunit derived from NanoLuc. Using HiBiT CRISPR/Cas9-modified cell lines in combination with fluorescent antibodies, we developed a HiBiT-BRET immunoassay (a.k.a. Immuno-BRET). This is a homogeneous immunoassay capable of monitoring post-translational modifications on diverse protein targets. Its usefulness was demonstrated for the detection of phosphorylation of multiple signaling pathway targets (EGFR, STAT3, MAPK8 and c-MET), as well as chromatin containing histone H3 acetylation on lysine 9 and 27. These results demonstrate the ability to efficiently monitor endogenous biological processes modulated by post-translational modifications using a small bioluminescent peptide tag and fluorescent antibodies, providing sensitive quantitation of the response dynamics to multiple stimuli.

The incidence, pathogenesis, and management of non-clear cell renal cell carcinoma

Renal cell carcinoma (RCC) is the most common type of kidney cancer and is divided into two distinct subtypes, clear cell renal cell carcinoma (ccRCC) and non-clear cell renal cell carcinoma (nccRCC). Although many treatments exist for RCC, these are largely based on clinical trials performed in ccRCC and there are limited studies on the management of nccRCC. Non-clear cell RCC consists of multiple histological subtypes: papillary, chromophobe, translocation, medullary, collecting duct, unclassified, and other rare histologies. Due to variations in pathogenesis and therapeutic response, therapy should be tailored to specific variant histologies. For patients with localized nccRCC, surgical resection remains the gold standard. In the metastatic setting, the standard of care has yet to be clearly defined, and most guidelines recommend clinical trial participation. General therapeutic options include immunotherapy, either as monotherapy or in combination, targeted therapies such as vascular endothelial growth factor tyrosine kinase inhibitors and MET inhibitors, and chemotherapy in certain subtypes. Here we present a review of the incidence and pathogenesis of the various subtypes, as well as available clinical data to support therapeutic recommendations for these subtypes. We also highlight currently available clinical trials in nccRCC and future directions in investigating novel treatment modalities tailored to patients with variant histology.

Mechanisms of tyrosine kinase inhibitor resistance in renal cell carcinoma

Renal cell carcinoma (RCC), the most prevalent type of kidney cancer, is a significant cause of cancer morbidity and mortality worldwide. Antiangiogenic tyrosine kinase inhibitors (TKIs), in combination with immune checkpoint inhibitors (ICIs), are among the first-line treatment options for patients with advanced RCC. These therapies target the vascular endothelial growth factor receptor (VEGFR) tyrosine kinase pathway and other kinases crucial to cancer proliferation, survival, and metastasis. TKIs have yielded substantial improvements in progression-free survival (PFS) and overall survival (OS) for patients with advanced RCC. However, nearly all patients eventually progress on these drugs as resistance develops. This review provides an overview of TKI resistance in RCC and explores different mechanisms of resistance, including upregulation of alternative proangiogenic pathways, epithelial-mesenchymal transition (EMT), decreased intracellular drug concentrations due to efflux pumps and lysosomal sequestration, alterations in the tumor microenvironment including bone marrow-derived cells (BMDCs) and tumor-associated fibroblasts (TAFs), and genetic factors such as single nucleotide polymorphisms (SNPs). A comprehensive understanding of these mechanisms opens the door to the development of innovative therapeutic approaches that can effectively overcome TKI resistance, thereby improving outcomes for patients with advanced RCC.

Mesenchymal-Epithelial Transition Kinase Inhibitor Therapy in Patients with Advanced Papillary Renal-Cell Carcinoma: A Systematic Review and Meta-Analysis

Papillary subtypes of renal-cell carcinoma (pRCC) represent 10-15% of the cases and commonly have MET alterations. This systematic review and single-arm meta-analysis evaluated MET inhibitor therapy (METi) efficacy and safety in adults with confirmed advanced pRCC. The search strategy included PubMed, Web-of-science, Cochrane, and Scopus. We used the DerSimonian/Laird random effect model for all analyses; p-value < 5% was considered significant, and heterogeneity was assessed with I2. Three clinical trials and six cohort studies were included with 504 patients; 31% were MET-driven. Our pooled analysis demonstrated an objective response rate (ORR) in MET-driven, MET-independent, and overall patients of: 36% (95%CI: 10-62), 0% (95%CI: 0-3), and 21% (95%CI: 1-41), respectively. One-year disease control and progression-free survival rates were, respectively, 70% (95%CI: 52-88) and 15% (95%CI: 10-20). Twelve- and twenty-four-month survival rates were, respectively, 43% (95%CI: 23-64) and 10% (95%CI: 0-30). The prevalence of adverse events of any grade and grades 3-5 were 96% (95%CI: 91-100) and 44% (95%CI: 37-50), respectively. We suggest METi has anti-tumor activity and is tolerable in patients with advanced pRCC.

An Overview of Systemic Targeted Therapy in Renal Cell Carcinoma, with a Focus on Metastatic Renal Cell Carcinoma and Brain Metastases

The most commonly diagnosed malignancy of the urinary system is represented by renal cell carcinoma. Various subvariants of RCC were described, with a clear-cell type prevailing in about 85% of all RCC tumors. Patients with metastases from renal cell carcinoma did not have many effective therapies until the end of the 1980s, as long as hormonal therapy and chemotherapy were the only options available. The outcomes were unsatisfactory due to the poor effectiveness of the available therapeutic options, but then interferon-alpha and interleukin-2 showed treatment effectiveness, providing benefits but only for less than half of the patients. However, it was not until 2004 that targeted therapies emerged, prolonging the survival rate. Currently, new technologies and strategies are being developed to improve the actual efficacy of available treatments and their prognostic aspects. This article summarizes the mechanisms of action, importance, benefits, adverse events of special interest, and efficacy of immunotherapy in metastatic renal cell carcinoma, with a focus on brain metastases.

Advanced Non-Clear Cell Renal Cell Carcinoma Treatments and Survival: A Real-World Single-Centre Experience

BACKGROUND

Non-clear cell renal cell carcinoma (nccRCC) is a heterogeneous group of cancer. Treatment recommendations are extrapolated from ccRCC and lack solid evidence. Here, we review advanced nccRCC patients treated at our institute.

PATIENTS AND METHODS

We collected retrospective data on all advanced nccRCC pts treated at the Istituto Oncologico Veneto from January 2008. We compared overall response rate (ORR), progression free survival (PFS) and overall survival (OS) according to histological subtypes and type of systemic treatments. Kaplan-Meier method, log-rank test and Cox regression were used to estimate and compare PFS and OS.

RESULTS

Of 1370 RCC patients, 289 had a diagnosis of nccRCC and 121 were eligible for the analysis. Fifty-three pts showed papillary histology (pRCC), 15 chromophobe; 37 unclassified RCC (NOS-RCC), 16 other histologies. Pts with chromophobe and other hystologies showed poorer survival rates compared to pRCC and NOS-RCC (mOS 10.7 vs. 20.7 vs. 30.7, p = 0.34). Pts treated with combination regimens achieved a better OS (30.7 vs. 13.7, p = 0.10), PFS (12.7 vs. 6.4, p = 0.10) and ORR (42.4% vs. 13.9%, p = 0.002) than those treated with monotherapy. IMDC and Meet-URO score retained their prognostic value.

CONCLUSION

Our retrospective real-life cohort of advanced nccRCC patients shows that immunotherapy-based combinations could improve ORR, PFS and OS compared to TKI monotherapy. Prospective trials for nccRCC patients utilizing novel therapies are ongoing and their results eagerly awaited.

Identification of Five Tumor Antigens for Development and Two Immune Subtypes for Personalized Medicine of mRNA Vaccines in Papillary Renal Cell Carcinoma

Increasing evidence has revealed the promise of mRNA-type cancer vaccines as a new direction for cancer immune treatment in several solid tumors, however, its application in papillary renal cell carcinoma (PRCC) remains unclear. The purpose of this study was to identify potential tumor antigens and robust immune subtypes for the development and appropriate use of anti-PRCC mRNA vaccines, respectively. Raw sequencing data and clinical information of PRCC patients were downloaded from The Cancer Genome Atlas (TCGA) database. The cBioPortal was utilized for the visualization and comparison of genetic alterations. The TIMER was used to assess the correlation between preliminary tumor antigens and the abundance of infiltrated antigen presenting cells (APCs). Immune subtypes were determined by the consensus clustering algorithm, and clinical and molecular discrepancies were further explored for a deeper understanding of immune subtypes. Five tumor antigens, including ALOX15B, HS3ST2, PIGR, ZMYND15 and LIMK1, were identified for PRCC, which were correlated with patients' prognoses and infiltration levels of APCs. Two immune subtypes (IS1 and IS2) were disclosed with obviously distinct clinical and molecular characteristics. Compared with IS2, IS1 exhibited a significantly immune-suppressive phenotype, which largely weakened the efficacy of the mRNA vaccine. Overall, our study provides some insights for the design of anti-PRCC mRNA vaccines and, more importantly, the selection of suitable patients to be vaccinated.

Navigating the Current Landscape of Non-Clear Cell Renal Cell Carcinoma: A Review of the Literature

Non-clear cell renal cell carcinoma (nccRCC) is an entity comprised of a heterogeneous constellation of RCC subtypes. Genomic profiling has broadened our understanding of molecular pathogenic mechanisms unique to individual nccRCC subtypes. To date, clinical trials evaluating the use of immunotherapies and targeted therapies have predominantly been conducted in patients with clear cell histology. A comprehensive review of the literature has been undertaken in order to describe molecular pathogenic mechanisms pertaining to each nccRCC subtype, and concisely summarise findings from therapeutic trials conducted in the nccRCC space.

Pembrolizumab Plus Axitinib for Metastatic Papillary and Chromophobe Renal Cell Carcinoma: NEMESIA (Non Clear MEtaStatic Renal Cell Carcinoma Pembrolizumab Axitinib) Study, a Subgroup Analysis of I-RARE Observational Study (Meet-URO 23a)

Non-clear cell renal cell carcinoma (nccRCC) represents a heterogeneous histological group which is 20-25% of those with renal cell carcinoma (RCC). Patients with nccRCC have limited therapeutic options due to their exclusion from phase III randomized trials. The aim of the present study was to investigate the effectiveness and tolerability of pembrolizumabaxitinib combination in chromophobe and papillary metastatic RCC (mRCC) patients enrolled in the I-RARE (Italian Registry on rAre genitor-uRinary nEoplasms) observational ongoing study (Meet-URO 23). Baseline characteristics, objective response rate (ORR), disease control rate (DCR) and progression-free survival (PFS) and toxicities were retrospectively and prospectively collected from nccRCC patients treated in 14 Italian referral centers adhering to the Meet-Uro group, from December 2020 to April 2022. Only patients with chromophobe and papillary histology were considered eligible for the present pre-specified analysis. There were 32 eligible patients who received pembrolizumab-axitinib as first-line treatment, of whom 13 (40%) had chromophobe histology and 19 (60%) were classified as papillary RCC. The DCR was 78.1% whereas ORR was 43.7% (11 patients achieved stable disease and 14 patients obtained partial response: 9/19 papillary, 5/13 chromophobe). Six patients (18.7%) were primary refractory. Median PFS was 10.8 months (95%CI 1.7-11.5). Eleven patients (34.3%) interrupted the full treatment due to immune-related adverse events (irAEs): G3 hepatitis (n = 5), G3 hypophisitis (n = 1), G3 diarrhea (n = 1), G3 pancreatitis (n = 1), G3 asthenia (n = 1). Twelve patients (37.5%) temporarily interrupted axitinib only due to persistent G2 hand-foot syndrome or G2 hypertension. Pembrolizumab-axitinib combination could be an active and feasible first-line treatment option for patients with papillary or chromophobe mRCC.

Inhibition of HSP 90 is associated with potent anti-tumor activity in Papillary Renal Cell Carcinoma

Background

There is no universally accepted treatment for patients with advanced papillary renal cell carcinoma (PRCC). The presence of activating mutations in MET, as well as gain of chromosome 7, where the MET gene is located, are the most common genetic alterations associated with PRCC, leading to the clinical evaluation of MET tyrosine kinase inhibitors (TKIs) in this cancer. However, TKIs targeting MET selectively, as well as multitargeted TKIs with activity against MET demonstrate modest efficacy in PRCC and primary and secondary treatment failure is common; other approaches are urgently needed to improve outcomes in these patients.

Methods

High throughput screening with small molecule libraries identified HSP90 inhibitors as agents of interest based on antitumor activity against patient derived PRCC cell lines. We investigated the activity of the orally available HSP90 inhibitor, SNX2112 in vitro, using 2D/3D PRCC cell culture models and in vivo, in mice tumor xenograft models. The molecular pathways mediating antitumor activity of SNX2112 were assessed by Western blot analysis, Flow cytometry, RNA-seq analysis, Real Time qPCR and imaging approaches.

Results

SNX2112 significantly inhibited cellular proliferation, induced G2/M cell cycle arrest and apoptosis in PRCC lines overexpressing MET. In contrast to TKIs targeting MET, SNX2112 inhibited both MET and known downstream mediators of MET activity (AKT, pAKT1/2 and pERK1/2) in PRCC cell lines. RNAi silencing of AKT1/2 or ERK1/2 expression significantly inhibited growth in PRCC cells. Furthermore, SNX2112 inhibited a unique set of E2F and MYC targets and G2M-associated genes. Interestingly, interrogation of the TCGA papillary RCC cohort revealed that these genes were overexpressed in PRCC and portend a poor prognosis. Finally, SNX-2112 demonstrated strong antitumor activity in vivo and prolonged survival of mice bearing human PRCC xenograft.

Conclusions

These results demonstrate that HSP90 inhibition is associated with potent activity in PRCC, and implicate the PI3K/AKT and MEK/ERK1/2 pathways as important mediators of tumorigenesis. These data also provide the impetus for further clinical evaluation of HSP90, AKT, MEK or E2F pathway inhibitors in PRCC.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-022-02416-z.

Tumorigenesis Mechanisms Found in Hereditary Renal Cell Carcinoma: A Review

Renal cell carcinoma is a heterogenous cancer composed of an increasing number of unique subtypes each with their own cellular and tumor behavior. The study of hereditary renal cell carcinoma, which composes just 5% of all types of tumor cases, has allowed for the elucidation of subtype-specific tumorigenesis mechanisms that can also be applied to their sporadic counterparts. This review will focus on the major forms of hereditary renal cell carcinoma and the genetic alterations contributing to their tumorigenesis, including von Hippel Lindau syndrome, Hereditary Papillary Renal Cell Carcinoma, Succinate Dehydrogenase-Deficient Renal Cell Carcinoma, Hereditary Leiomyomatosis and Renal Cell Carcinoma, BRCA Associated Protein 1 Tumor Predisposition Syndrome, Tuberous Sclerosis, Birt-Hogg-Dubé Syndrome and Translocation RCC. The mechanisms for tumorigenesis described in this review are beginning to be exploited via the utilization of novel targets to treat renal cell carcinoma in a subtype-specific fashion.

Contemporary Drug Therapy for Renal Cell Carcinoma- Evidence Accumulation and Histological Implications in Treatment Strategy

Renal cell carcinoma (RCC) is a heterogeneous disease comprising a variety of histological subtypes. Approximately 70-80% of RCC cases are clear cell carcinoma (ccRCC), while the remaining subtypes constitute non-clear cell carcinoma (nccRCC). The medical treatment of RCC has greatly changed in recent years through advances in molecularly targeted therapies and immunotherapies. Most of the novel systemic therapies currently available have been approved based on ccRCC clinical trial data. nccRCC can be subdivided into more than 40 histological subtypes that have distinct clinical, histomorphological, immunohistochemical, and molecular features. These entities are listed as emerging in the 2022 World Health Organization classification. The diagnosis of nccRCC and treatments based on cancer histology and biology remain challenging due to the disease's rarity. We reviewed clinical trials focused on recent discoveries regarding clinicopathological features.

Bioinformatically Expanded Next-Generation Sequencing Analysis Optimizes Identification of Therapeutically Relevant MET Copy Number Alterations in >50,000 Tumors

PURPOSE

Clinical relevance thresholds and laboratory methods are poorly defined for MET amplification, a targetable biomarker across malignancies.

EXPERIMENTAL DESIGN

The utility of next-generation sequencing (NGS) in assessing MET copy number alterations was determined in >50,000 solid tumors. Using fluorescence in situ hybridization as reference, we validated and optimized NGS analysis.

RESULTS

Incorporating read-depth and focality analyses achieved 91% concordance, 97% sensitivity, and 89% specificity. Tumor heterogeneity, neoplastic cell proportions, and genomic focality affected MET amplification assessment. NGS methodology showed superiority in capturing overall amplification status in heterogeneous tumors and defining amplification focality among other genomic alterations. MET copy gains and amplifications were found in 408 samples across 23 malignancies. Total MET copy number inversely correlated with amplified segment size. High-level/focal amplification was enriched in certain genomic subgroups and associated with targeted therapy response.

CONCLUSIONS

Leveraging our integrated bioinformatic approach, targeted therapy benefit was observed across diverse MET amplification contexts.

Phosphoproteomic analysis of FLCN inactivation highlights differential kinase pathways and regulatory TFEB phosphoserines

In Birt-Hogg-Dubé (BHD) syndrome, germline mutations in the Folliculin (FLCN) gene lead to an increased risk of renal cancer. To address how FLCN affects cellular kinase signaling pathways, we analyzed comprehensive phosphoproteomic profiles of FLCN^POS and FLCN^NEG human renal tubular epithelial cells (RPTEC/TERT1). In total, 15744 phosphorylated peptides were identified from 4329 phosphorylated proteins. INKA analysis revealed that FLCN loss alters the activity of numerous kinases, including tyrosine kinases EGFR, MET and the Ephrin receptor subfamily (EPHA2 and EPHB1), as well their downstream targets MAPK1/3. Validation experiments in the BHD renal tumor cell line UOK257 confirmed that FLCN loss contributes to enhanced MAPK1/3 and downstream RPS6K1/3 signaling. The clinically available MAPK inhibitor Ulixertinib showed enhanced toxicity in FLCN^NEG cells. Interestingly, FLCN inactivation induced the phosphorylation of PIK3CD (Tyr524) without altering the phosphorylation of canonical Akt1/Akt2/mTOR/EIF4EBP1 phosphosites. Also, we identified that FLCN inactivation resulted in dephosphorylation of TFEB Ser109, Ser114 and Ser122, which may be caused by fact that FLCN^NEG cells experience oxidative stress. Together, our study highlights differential phosphorylation of specific kinases and substrates in FLCN^NEG renal cells. This provides insight into BHD-associated renal tumorigenesis and may point to several novel candidates for targeted therapies.

Impact of MET status on treatment outcomes in papillary renal cell carcinoma: A pooled analysis of historical data

BACKGROUND

Papillary renal cell carcinoma (PRCC) represents 15% of RCCs but has no indicated therapies, with limited biomarker-based data to inform targeted treatment. MET alterations may be key; > 80% of PRCC tumours show MET upregulation. The objective of this study was to assess MET status in PRCC and its impact on clinical outcomes.

METHODS

This retrospective, observational study included patients with locally advanced/metastatic PRCC from three international registries. MET status was determined retrospectively by next generation sequencing (NGS) of archival tissue. MET-driven was defined as MET and/or hepatocyte growth factor amplification, chromosome 7 gain, and/or MET kinase domain mutations. Objectives included progression-free survival (PFS) and overall survival (OS) by MET status using a Cox proportional hazards model.

RESULTS

Of 308 patients, 305 received first-line treatment; most commonly sunitinib (n = 208; 68%), then everolimus (n = 40; 13%). Of 179 patients with valid NGS results, 38% had MET-driven and 49% MET-independent tumours (13% unevaluable). In the MET-driven versus MET-independent subgroups, respectively, of sunitinib-treated patients, median PFS was numerically longer, though not statistically significantly; PFS: 9.2 months (95% confidence interval [CI]: 5.4-13.2) versus 5.7 months (95% CI: 4.3-7.4), hazard ratio (HR) = 0.67; 95% CI: 0.41-1.08. There was no difference between the OS of each subgroup.

CONCLUSIONS

MET-driven PRCC may respond to targeted agents. However, the presence of MET alterations did not appear to be predictive for outcomes in response to current therapies, which are not biomarker-driven, compared with MET-independent tumours.

Activity of ALK Inhibitors in Renal Cancer with ALK Alterations: A Systematic Review

Renal cell carcinoma (RCC) associated with anaplastic lymphoma kinase (ALK) gene rearrangements (ALK-RCC) is currently considered an “emerging or provisional” tumor entity by the last World Health Organization classification published in 2016. Although several studies assessing ALK-RCC’s clinical and histological characteristics have been published in recent years, only a few publications have evaluated the activity of ALK inhibitors (ALK-i) in this subgroup of patients. Considering the well-recognized efficacy of this evolving class of targeted therapies in other ALK-positive tumors, we conducted a systematic review to evaluate the reported activity of ALK-i in the ALK-RCC subtype. MEDLINE was searched from its inception to 7 January 2022 for case reports and case series on adult metastatic ALK-RCC patients treated with ALK-i whose therapeutic outcomes were available. A virtual cohort of ALK-RCC patients was created. Our results showed a favorable activity of first- and second-generation ALK-i in pretreated ALK-RCC patients in terms of either radiological response or performance status improvement. We hope that the present work will prompt the creation of large, multi-institutional clinical trials to confirm these promising early data.

Comprehensive Analysis of Pyroptosis-Related Genes and Tumor Microenvironment Infiltration Characterization in Papillary Renal Cell Carcinoma

Background: Immunotherapy has emerged as an important technique for treating a variety of cancers. The dynamic interplay between tumor cells and invading lymphocytes in the tumor microenvironment is responsible for the good response to immunotherapy (TME). Pyroptosis, or inflammation-induced cell death, is closely linked to a number of cancers. However, in papillary renal cell carcinoma (KIRP), the association between pyroptosis and clinical prognosis, immune cell infiltration, and immunotherapy impact remains unknown.

Methods: We carefully investigated the link between pyroptosis and tumor growth, prognosis, and immune cell infiltration by evaluating 52 pyroptosis-related genes. The PRG score was utilized to measure a single tumor patient’s pyroptosis pattern. After that, we looked at how well these values predicted prognoses and therapy responses in KIRP.

Results: We discovered that PRG differences between subgroups were linked to clinical and pathological aspects, prognosis, and TME in two separate genetic subtypes. After that, a PRG score for estimating overall survival (OS) was developed, and its predictive potential in KIRP patients was confirmed. As a result, we developed a very precise nomogram to improve the PRG score’s clinical usefulness. A low PRG score, which is determined by mutation load and immune activation, suggests a good chance of survival. Furthermore, the PRG score was linked to chemotherapeutic drug sensitivity in a substantial way.

Conclusions: The possible functions of PRGs in the TME, clinical and pathological characteristics, and prognosis were established in our thorough investigation of PRGs in KIRP. These results might help us better understand PRGs in KIRP and offer a new avenue for prognostic evaluation and the development of more effective immunotherapy treatments.

Reviewing Treatment Options for Advanced Renal Cell Carcinoma: Is There Still a Place for Tyrosine Kinase Inhibitor (TKI) Monotherapy?

Renal cell carcinoma (RCC) comprises a highly heterogeneous group of kidney tumours built upon distinct genetic- and epigenetic-driven mechanisms and molecular pathways. Therefore, responsiveness to treatment is considerably variable across patients, adding an extra layer of complexity to the already challenging therapeutic decision process. The last decade brought an unprecedented shift in the medical approach to advanced or metastatic RCC; in fact, immunotherapy-based combinations have significantly transformed the therapeutic arsenal and clinical outcomes of these patients. These strategies were quickly adopted by international guidelines committees as the new standards of care. However, this enhanced efficacy comes at the expense of tolerability, with a predictable negative impact on patients' quality of life. Moreover, subgroup and post hoc analyses of the major clinical trials have shown that not all patients benefit equally from these innovative approaches. In this context, a group of experts on kidney cancer met and discussed the state of the art in the field, with a special emphasis on the appropriateness of using monotherapy with an anti-angiogenesis tyrosine kinase inhibitor (TKI) to treat specific subgroups of patients with RCC. This article reviews the main topics that were considered to be pertinent for that discussion and establishes the profile of patients for whom TKI monotherapy remains a sensible frontline option by avoiding overtreatment and an unnecessary exposure to treatment-related toxicity.

MET-Targeted Therapies and Clinical Outcomes: A Systematic Literature Review

Introduction

Numerous therapeutic agents specifically targeting the mesenchymal-epithelial transition (MET) oncogene are being developed.

Objective

The aim of the current review was to systematically identify and analyze clinical trials that have evaluated MET inhibitors in various cancer types and to provide an overview of their clinical outcomes.

Methods

An electronic literature search was carried out in the PubMed and Embase databases to identify published clinical trials related to MET inhibitors. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement was followed for the systematic appraisal of the literature. Data related to clinical outcomes, including progression-free survival, overall survival, objective response rate, and overall tumor response, were extracted.

Results

In total, 49 publications were included. Among these, 51.02% were phase II studies, 14.28% were randomized controlled trials, three were phase III studies, two were prospective observational studies, and the remainder were either phase I or Ib studies. The majority (44.89%) of articles reported the clinical outcomes of MET inhibitors, including small molecules, monoclonal antibodies, and other agents, in patients with non-small-cell lung cancer (NSCLC) harboring MET alterations. MET amplification, overexpression, and MET exon 14 skipping mutations were the major MET alteration types reported across the included studies. Clinical responses/outcomes varied considerably.

Conclusion

This systematic literature review provides an overview of the literature available in Embase and PubMed regarding MET-targeted therapies. MET-selective tyrosine kinase inhibitors (TKIs) (capmatinib, tepotinib, and savolitinib) may become a new standard of care in NSCLC, specifically with MET exon 14 skipping mutations. A combination of MET TKIs with epidermal growth factor receptor (EGFR) TKIs (osimertinib + savolitinib, tepotinib + gefitinib) may be a potential solution for MET-driven EGFR TKI resistance. Further, MET alteration (MET amplification/overexpression) may be an actionable target in gastric cancer and papillary renal cell carcinoma.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with renal cell carcinoma

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of renal cell carcinoma was published in 2019 with an update planned for 2021. It was therefore decided by both the ESMO and the Singapore Society of Oncology (SSO) to convene a special, virtual guidelines meeting in May 2021 to adapt the ESMO 2019 guidelines to take into account the ethnic differences associated with the treatment of renal cell carcinomas in Asian patients. These guidelines represent the consensus opinions reached by experts in the treatment of patients with renal cell carcinoma representing the oncological societies of China (CSCO), India (ISMPO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence and was independent of the current treatment practices and drug access restrictions in the different Asian countries. The latter were discussed when appropriate.

Metabolomic Profiling in Renal Cell Carcinoma Patients: News and Views

BACKGROUND

We address novelty regarding metabolomic profiling in renal cell carcinoma (RCC) patients, in an attempt to postulate potential treatment strategies.

METHODS

A large-scale literature search in existing scientific websites focusing on the keywords "renal cell carcinoma", "clear cell histology", "papillary histology", "metabolomic profiling", and "therapeutics" was performed. Results: The PI3K/Akt signaling pathway is key in clear cell RCC metabolism and accordingly several drugs are presently available for routine use in clinical practice. Along this line, new treatment combinations against PI3K/Akt family members are currently under clinical investigation. On the other hand, new developed targets such as c-Met tyrosine kinase domain, glutathione (GSH) metabolism, and histone deacetylases enzymes (HDAC), as well as therapeutic strategies targeting them are currently being tested in clinical trials and here discussed.

CONCLUSIONS

In RCC patients, the PI3K/Akt signaling is still the most effective targetable pathway. Targeting other metabolic pathways such as c-Met, GSH, and HDAC appears to be a promising approach and deserve further insights.

Novel Prognostic Immunohistochemical Markers in Uveal Melanoma-Literature Review

Simple Summary

The following study provides an overview of the English-language literature on the search for new prognostic factors for uveal melanoma. Uveal melanoma is the most common primary intraocular tumor in adults, and although it is a relatively rare disease, it poses a significant health problem. About half of the patients develop distant metastases, and unfortunately there are currently no effective treatments for the disease at such an advanced stage. The search for new prognostic factors is important to understand the biology of the disease and to be able to monitor patients more effectively. At the same time, it creates an opportunity to find new therapeutic targets. We focused our attention on immunohistochemical research because it is a widely used method, relatively cheap, technically simple, and gives reproducible results. The analysis of this study will enable other researchers to verify their research plans and may also be a source of inspiration for creating new ones.

Abstract

Uveal melanoma is the most common primary intraocular neoplasm in adults. As there are currently no effective methods of treating the disease in the metastatic stage, there is a need to search for new prognostic factors that would enable a reliable assessment of the patient’s condition and constitute a possible therapeutic target. In this review, we have prepared the results of English-language studies on new prognostic factors determined with immunohistochemical methods. We found 64 articles in which the expression of various proteins was associated in a statistically significant manner with the histopathological and clinical prognostic factors identified by AJCC. The results of our work clearly show that the biology of uveal melanoma is extraordinarily complex. Numerous studies have shed new light on the complexity of the processes involved in the development of this cancer. Moreover, a careful analysis of the expression of individual proteins may allow the identification of homogeneous groups of patients requiring different treatment regimens.

Characteristics and Treatment Challenges of Non-Clear Cell Renal Cell Carcinoma

Non-clear cell renal cell carcinomas (RCC) comprise several rare and poorly described diseases, often characterized by bad prognosis and with no standard treatments available. The gap in their clinical management is linked to the poor molecular characterization in handling the treatment of non clear-cell RCC with untailored therapies. Due to their rarity, non-clear RCC are in fact under-represented in prospective randomized trials. Thus, treatment choices are based on extrapolating results from clear cell RCC trials, retrospective data, or case reports. Over the last two decades, various options have been considered as the mainstay for the treatment of metastatic RCC (mRCC), including angiogenesis inhibitors, vascular endothelial growth factor receptor inhibitors, other tyrosine kinase inhibitors (TKIs), as well as MET inhibitors and mammalian targeting of rapamycin (mTOR) inhibitors. More recently, the therapeutic armamentarium has been enriched with immunotherapy, alone or in combination with targeted agents that have been shown to significantly improve outcomes of mRCC patients, if compared to TKI single-agent. It has been widely proven that non-clear cell RCC is a morphologically and clinically distinct entity from its clear cell counterpart but more knowledge about its biology is certainly needed. Histology-specific collaborative trials are in fact now emerging to investigate different treatments for non-clear cell RCC. This review summarizes pathogenetic mechanisms of non-clear cell RCC, the evolution of treatment paradigms over the last few decades, with a focus on immunotherapy-based trials, and future potential treatment options.

Kidney cancer: from genes to therapy

Renal cell carcinoma incidence is rising worldwide with increasing subtype stratification by the World Health Organization. Each subtype has unique genetic alterations, cell biology changes and clinical findings. Such genetic alterations offer the potential for individualized therapeutic approaches that are rapidly progressing. This review highlights the most common subtypes of renal cell carcinoma, including both hereditary and sporadic forms, with a focus on genetic changes, clinical findings and ongoing clinical trials.

The Molecular Characteristics of Non-Clear Cell Renal Cell Carcinoma: What's the Story Morning Glory?

Non-clear cell renal cell carcinomas are a miscellaneous group of tumors that include different histological subtypes, each one characterized by peculiarity in terms of genetic alteration, clinical behavior, prognosis, and treatment response. Because of their low incidence and poor enrollment in clinical trials, alongside their heterogeneity, additional efforts are required to better unveil the pathogenetic mechanisms and, consequently, to improve the treatment algorithm. Nowadays, tyrosine kinase inhibitors, mTOR and MET inhibitors, and even cisplatin-based chemotherapy and immunotherapy are potential weapons that are still under evaluation in this setting. Various biomarkers have been evaluated for detecting progression and monitoring renal cell carcinoma, but more studies are necessary to improve this field. In this review, we provide an overview on the molecular characteristics of this group of tumors and the recently published trials, giving an insight into what might become the future therapeutic standard in this complex world of non-clear cell kidney cancers.

Papillary renal cell carcinoma: Review

Kidney cancer is the 13th most common malignancy globally, and the incidence is rising. Papillary renal cell carcinoma is the second most common subtype, comprising 10-15% of renal cell carcinomas. Though the histologic features of this subtype were initially described in the 1990's, our understanding of the genetic and molecular characteristics of this disease have rapidly evolved over the past decade. In this review, we summarize the contemporary understanding of the clinical, morphologic, radiographic, and genetic characteristics of papillary renal cell carcinoma, as well as clinical considerations, current options for management, and prognosis.

Response to systemic therapy in fumarate hydratase-deficient renal cell carcinoma

PURPOSE

Fumarate hydratase-deficient (FHdef) renal cell carcinoma (RCC) is a rare entity associated with the hereditary leiomyomatosis and RCC syndrome with no standard therapy approved. The aim of this retrospective study was to evaluate the efficacy of different systemic treatments in this population.

METHODS

We performed a multicentre retrospective analysis of Fhdef RCC patients to determine the response to systemic treatments. The endpoints were objective response rate (ORR), time-to-treatment failure (TTF), and overall survival (OS). The two latter were estimated using the Kaplan-Meier method.

RESULTS

Twenty-four Fhdef RCC patients were identified, and 21 under systemic therapy were included in the analysis: ten received cabozantinib, 14 received sunitinib, nine received "other antiangiogenics" (sorafenib, pazopanib, and axitinib), three received erlotinib-bevacizumab (E-B), three received mTOR inhibitors, and 11 received immune checkpoint blockers (ICBs). ORR for treatments were 50% for cabozantinib, 43% for sunitinib, 63% for "other antiangiogenics," and 30% for E-B, whereas ORR was 0% for mTOR inhibitors and 18% for ICBs. The median TTF (mTTF) was significantly higher with antiangiogenics (11.6 months) than with mTOR inhibitors (4.4 months) or ICBs (2.7 months). In the first-line setting, antiangiogenics presented a higher ORR compared with nivolumab-ipilimumab (64% versus 25%) and a significantly superior mTTF (11.0 months vs 2.5 months; p = 0.0027). The median OS from the start of the first systemic treatment was 44.0 months (95% confidence interval: 13.0-95.0).

CONCLUSIONS

We report the first European retrospective study of Fhdef RCC patients treated with systemic therapy with a remarkably long median OS of 44.0 months. Our results suggest that antiangiogenics may be superior to ICB/mTOR inhibitors in this population.

A challenging frontier - the genomics and therapeutics of nonclear cell renal cell carcinoma

PURPOSE OF REVIEW

As molecular profiling of renal cell carcinoma (RCC) continues to elucidate novel targets for nonclear cell histologies, understanding the landscape of these targets is of utmost importance. In this review, we highlight the genomic landscape of nonclear cell RCC and its implications for current and future systemic therapies.

RECENT FINDINGS

Several genomic studies have described the mutational burden among nonclear cell histologies. These studies have highlighted the importance of MET in papillary RCC and led to several clinical trials evaluating the efficacy of MET inhibitors for papillary RCC. The success of immune checkpoint inhibitors, such as ipilimumab and nivolumab, in clear cell RCC has led to ongoing trials evaluating these novel therapeutics in nonclear cell RCC.

SUMMARY

Genomic profiling has allowed for the evaluation of novel targets for nonclear cell RCC. This evolving therapeutic landscape is being explored in promising, ongoing trials that have the potential for changing how nonclear cell RCC is managed.

Non-clear cell renal carcinomas: Review of new molecular insights and recent clinical data

Non-clear cell renal cell carcinomas (nccRCC) represent a highly heterogeneous group of kidney tumors, consisting of the following subtypes: papillary carcinomas, chromophobe renal cell carcinoma, so-called unclassified carcinomas or aggressive uncommon carcinomas such as Bellini carcinoma, renal cell carcinoma (RCC) with ALK rearrangement or fumarate hydratase-deficient RCC. Although non-clear cell cancers account for only 15 to 30% of renal tumors, they are often misclassified and accurate diagnosis continues to be an issue in clinical practice. Current therapeutic strategy of metastatic nccRCC is based primarily on guidelines established for clear cell tumors, the most common subtype, however this approach remains poorly defined. To date, published clinical trials for all histological nccRCC subtypes have been collectively characterized into one group, in contrast to clear cell RCC, and given the small numbers of cases, the interpretation of study results continues to be challenging. This review summarizes the available literature for each nccRCC subtype and highlights the lack of supportive evidence from prospective clinical trials and retrospective studies. Future trials should evaluate treatment approaches which focus on a specific histological subtype and progress in treating nccRCC will be contingent on understanding the unique biology of their individual histologies.

Systemic Therapies for the Management of Non-Clear Cell Renal Cell Carcinoma: What Works, What Doesn't, and What the Future Holds

Non-clear cell renal cell carcinoma (nccRCC) is a broad term that refers to a diverse group of tumors, each with its own distinct biologic and therapeutic profile. The management of nccRCCs is often based on extrapolating data from clinical trials in the more common clear cell renal cell carcinoma, but our emerging prospective and retrospective clinical experience in nccRCC allows us to make more precise recommendations tailored to each histology. The systemic therapy options for metastatic nccRCC include targeted therapies such as tyrosine kinase inhibitors, immune checkpoint inhibitors, and, for specific rare subtypes, cytotoxic chemotherapy. Each nccRCC histology may respond differently to these regimens, which makes accurate pathologic diagnosis imperative. In the present review, we discuss the available clinical and biological data that can help guide systemic therapy recommendations for specific nccRCC subtypes.

MET alterations in biphasic squamoid alveolar papillary renal cell carcinomas and clinicopathological features

Biphasic squamoid alveolar papillary renal cell carcinoma (BSA-PRCC) is a recently studied lesion considered a morphologic variant of papillary renal cell carcinoma (RCC), more closely related to type 1. Considering the role of proto-oncogene MET in both sporadic type 1 papillary RCC and hereditary papillary RCC, we aimed to explore the role of MET activation in the oncogenesis of BSA-PRCC. We identified 17 patients with either unique (n = 14) or multiple (n = 3) BSA-PRCC, all localized, and performed an integrative analysis of MET status in 18 formalin-fixed paraffin-embedded tumors combining next-generation sequencing analysis, fluorescent in situ hybridization and immunohistochemistry. Trisomy 7 was found in 86% of tumors (14/16) without MET amplification at 7q31 (15/15). A pathogenic MET genetic variant was identified in 60% (9/15) of cases, at the germline level in 57% (4/7) of tested patients or at the somatic level (5/11). MET expression was observed in all tumors with a higher value of combined score in large cells (mean 97%, range 80-100%) than in small cells (mean 74%, range 10-100%) and was lower in two cases without MET copy number gain. In conclusion, our study provides additional evidence to consider biphasic squamoid alveolar papillary RCC as a morphological variant of type 1 papillary renal RCC. Our data strongly suggest that MET represents a major oncogenic driver gene in BSA-PRCC, harboring a higher frequency of MET mutation that encourages to further explore the benefice of anti-MET targeted therapies for aggressive BSA-PRCC.

Anti-tumor efficacy of human anti-c-met CAR-T cells against papillary renal cell carcinoma in an orthotopic model

Chimeric antigen receptor (CAR)‐T cell therapy has shown salient efficacy in cancer immunotherapy, particularly in the treatment of B cell malignancies. However, the efficacy of CAR‐T for solid tumors remains inadequate. In this study, we displayed that c‐met is an appropriate therapeutic target for papillary renal cell carcinoma (PRCC) using clinical samples, developed an anti‐human c‐met CAR‐T cells, and investigated the anti‐tumor efficacy of the CAR‐T cells using an orthotopic mouse model as pre‐clinical research. Administration of the anti‐c‐met CAR‐T cells induced marked infiltration of the CAR‐T cells into the tumor tissue and unambiguous suppression of tumor growth. Furthermore, in combination with axitinib, the anti‐tumor efficacy of the CAR‐T cells was synergistically augmented. Taken together, our current study demonstrated the potential for clinical application of anti‐c‐met CAR‐T cells in the treatment of patients with PRCC.

A comparison of sunitinib with cabozantinib, crizotinib, and savolitinib for treatment of advanced papillary renal cell carcinoma: a randomised, open-label, phase 2 trial

BACKGROUND

MET (also known as hepatocyte growth factor receptor) signalling is a key driver of papillary renal cell carcinoma (PRCC). Given that no optimal therapy for metastatic PRCC exists, we aimed to compare an existing standard of care, sunitinib, with the MET kinase inhibitors cabozantinib, crizotinib, and savolitinib for treatment of patients with PRCC.

METHODS

We did a randomised, open-label, phase 2 trial done in 65 centres in the USA and Canada. Eligible patients were aged 18 years or older with metastatic PRCC who had received up to one previous therapy (excluding vascular endothelial growth factor-directed and MET-directed agents). Patients were randomly assigned to receive sunitinib, cabozantinib, crizotinib, or savolitinib, with stratification by receipt of previous therapy and PRCC subtype. All drug doses were administered orally: sunitinib 50 mg, 4 weeks on and 2 weeks off (dose reductions to 37·5 mg and 25 mg allowed); cabozantinib 60 mg daily (reductions to 40 mg and 20 mg allowed); crizotinib 250 mg twice daily (reductions to 200 mg twice daily and 250 mg once daily allowed); and savolitinib 600 mg daily (reductions to 400 mg and 200 mg allowed). Progression-free survival (PFS) was the primary endpoint. Analyses were done in an intention-to-treat population, with patients who did not receive protocol therapy excluded from safety analyses. This trial is registered with ClinicalTrials.gov, NCT02761057.

FINDINGS

Between April 5, 2016, and Dec 15, 2019, 152 patients were randomly assigned to one of four study groups. Five patients were identified as ineligible post-randomisation and were excluded from these analyses, resulting in 147 eligible patients. Assignment to the savolitinib (29 patients) and crizotinib (28 patients) groups was halted after a prespecified futility analysis; planned accrual was completed for both sunitinib (46 patients) and cabozantinib (44 patients) groups. PFS was longer in patients in the cabozantinib group (median 9·0 months, 95% CI 6-12) than in the sunitinib group (5·6 months, 3-7; hazard ratio for progression or death 0·60, 0·37-0·97, one-sided p=0·019). Response rate for cabozantinib was 23% versus 4% for sunitinib (two-sided p=0·010). Savolitinib and crizotinib did not improve PFS compared with sunitinib. Grade 3 or 4 adverse events occurred in 31 (69%) of 45 patients receiving sunitinib, 32 (74%) of 43 receiving cabozantinib, ten (37%) of 27 receiving crizotinib, and 11 (39%) of 28 receiving savolitinib; one grade 5 thromboembolic event was recorded in the cabozantinib group.

INTERPRETATION

Cabozantinib treatment resulted in significantly longer PFS compared with sunitinib in patients with metastatic PRCC.

FUNDING

National Institutes of Health and National Cancer Institute.

Combination of HGF/MET-targeting agents and other therapeutic strategies in cancer

MET receptor has emerged as a druggable target across several human cancers. Agents targeting MET and its ligand hepatocyte growth factor (HGF) including small molecules such as crizotinib, tivantinib and cabozantinib or antibodies including rilotumumab and onartuzumab have proven their values in different tumors. Recently, capmatinib was approved for treatment of metastatic lung cancer with MET exon 14 skipping. In this review, we critically examine the current evidence on how HGF/MET combination therapies may take advantage of synergistic effects, overcome primary or acquired drug resistance, target tumor microenvironment, modulate drug metabolism or tackle pharmacokinetic issues. Preclinical and clinical studies on the combination of HGF/MET-targeted agents with conventional chemotherapeutics or molecularly targeted treatments (including EGFR, VEGFR, HER2, RAF/MEK, and PI3K/Akt targeting agents) and also the value of biomarkers are examined. Our deeper understanding of molecular mechanisms underlying successful pharmacological combinations is crucial to find the best personalized treatment regimens for cancer patients.

Anaplastic lymphoma kinase (ALK) rearrangement in adult renal cell carcinoma with lung metastasis: a case report and literature review

Renal cell carcinoma (RCC) with anaplastic lymphoma kinase (ALK) rearrangement is rare, and the genetic profiles of the tumor have not been elucidated. Here, we report a case with recurrent papillary RCC and lung metastasis after nephrectomy for nearly 7 years. The patient first received sunitinib, whereas the drug toxicity was intolerable. Combined Immunohistology (IHC) and fluorescence in situ hybridization (FISH) revealed the patient has an ALK rearrangement, and the patient then was treated with crizotinib. The patient had good tolerance, and a partial response in the target lesions was achieved. In order to further understand the benefit of crizotinib in ALK-rearranged RCC, the patient was detected with whole exome sequencing (WES) to study her genetic profiles. Compared those of RCC cases without ALK rearrangement (nALK-RCC), the patient and nine RCC cases with ALK rearrangement (ALK-RCC) revealed unique genetic characteristics: 1) The common mutations that occurred in RCC were not found in ALK-RCC.; 2) A total of 11 co-existing mutations in ALK-RCC were found, and they occurred in nALK-RCC at a relatively low frequency. DNMT3A mutations were concurrent with ALK fusions in our case. These findings indicated a different genetic alteration pattern of ALK-RCC from nALK-RCC. Our case demonstrated the efficacy of crizotinib in an RCC patient with ALK rearrangement.

Are tyrosine kinase inhibitors fit for purpose in the treatment of metastatic papillary renal cell carcinoma?

Renal cell carcinoma encompasses a range of histological subtypes. The treatment of metastatic disease in this context remains challenging. Papillary renal cell carcinoma is the second most common subtype and forms a significant subsection of non-clear cell renal cell carcinoma. Tyrosine kinase inhibitors form a significant part of the treatment of this largely incurable disease; however, outcomes tend to be poor. The aim of this article is to scrutinise whether these treatments are evidence-based in their use for metastatic papillary renal cell carcinoma and if good outcomes are reported. A literature review was made using PubMed of major prospective and retrospective studies. The European Association of Urology and European Society of Medical Oncology have both published guidance suggesting sunitinib should be offered first line in the treatment of metastatic papillary renal cell carcinoma. This, however, is based upon weak evidence produced by the ASPEN trial, although this did not discriminate between non-clear cell subtypes and results in further studies were modest. The National Institute for Care and Health Excellence has recently published new guidelines for the use of cabozantinib, which has shown evidence of improved progression-free survival and overall response rates compared with sunitinib. Unfortunately, many of the relevant studies did not specifically assess these treatments in patients solely with papillary renal cell carcinoma and had modest overall success. There is weak evidence that tyrosine kinase inhibitors give significant benefit in those patients with metastatic papillary renal cell carcinoma.

Level of evidence: 2a

Tropomyosin receptor kinase inhibitors in the management of sarcomas

PURPOSE OF REVIEW

Genetic aberrations resulting in tropomyosin receptor kinase (TRK) fusion proteins can drive oncogenesis and are postulated to occur in up to 1% of solid tumours. However, TRK fusions in adult sarcomas are rare and there is a significant challenge in identifying patients with sarcomas harbouring TRK fusions in the clinical setting. Despite a recent European Society of Medical Oncology consensus article regarding screening of tumours for TRK fusions, economical and practical limitations present a barrier to widespread screening of sarcomas.

RECENT FINDINGS

Larotrectinib and entrectinib are pan-TRK inhibitors which have both received FDA approval for the management of solid tumours harbouring NTRK fusions. Initial results of a number of clinical trials have demonstrated promising efficacy and safety data, including dramatic and durable responses in patients with sarcomas. As such, TRK inhibitors represent a promising treatment option in a small cohort of adult sarcoma patients, where currently treatment options are limited. The emergence of acquired resistance is a concern associated with TRK inhibitor therapy and a number of second-generation agents targeting TRK kinase mutations driving acquired resistance have entered early-phase clinical trials.

SUMMARY

With the growing appreciation of the implications of TRK fusions, this review will summarize the emerging clinical trial data of TRK inhibitors in sarcomas. Although in their infancy, clinical trial results are encouraging, and as further results and analyses are released, we will have a greater understanding of their impact on clinical practice and the management of patients with sarcomas.

Everolimus plus bevacizumab is an effective first-line treatment for patients with advanced papillary variant renal cell carcinoma: Final results from a phase II trial

BACKGROUND

We previously reported on a phase 2 study of everolimus plus bevacizumab across various nonclear cell renal cell carcinoma (nccRCC) histologies and observed encouraging activity among patients with papillary RCC (pRCC) and unclassified RCC (uRCC) with a major papillary component. We subsequently expanded the study to enroll additional patients with pRCC variants.

METHODS

Everolimus plus bevacizumab was administered at standard doses until disease progression or intolerance to therapy. The primary endpoint was the 6-month progression-free survival (PFS) rate; secondary endpoints included objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and safety. Correlative analyses included next-generation sequencing (NGS) from tumor and germline across >341 genes of interest.

RESULTS

In addition to 19 patients with pRCC variants in the original cohort, 20 patients with similar features were enrolled on the expansion cohort (uRCC with papillary features [n = 24], pRCC [n = 14], and translocation-associated RCC with papillary features [n = 1]). Among 37 evaluable patients, the 6-month PFS rate was 78%, the median PFS was 13.7 months (95% CI, 10.8-16.4 months), and the ORR was 35%. With a median follow-up of 17.6 months, the median OS was 33.9 months (95% CI, 23.3-71.9). Tolerance was consistent with prior reports for everolimus plus bevacizumab. NGS results (n = 33) identified responses in patients with a wide spectrum of genomic alterations, including ARID1A, FH, and MET mutations.

CONCLUSION

The expansion cohort results confirm robust activity of everolimus plus bevacizumab in metastatic pRCC variants, supporting this regimen as a standard option for this patient population.