First-line treatment of metastatic clear cell renal cell carcinoma: a decision-making analysis among experts

Metastatic Kidney Cancer: Does the Location of the Metastases Matter? Moving towards Personalized Therapy for Metastatic Renal Cell Carcinoma

The management of renal cell carcinoma (RCC) has been revolutionized over the past two decades with several practice-changing treatments. Treatment for RCC often requires a multimodal approach: Local treatment, such as surgery or ablation, is typically recommended for patients with localized tumors, while stage IV cancers often require both local and systemic therapy. The treatment of advanced RCC heavily relies on immunotherapy and targeted therapy, which are highly contingent upon histological subtypes. Despite years of research on biomarkers for RCC, the standard of care is to choose systemic therapy based on the risk profile according to the International Metastatic RCC Database Consortium and Memorial Sloan Kettering Cancer Centre models. However, many questions still need to be answered. Should we consider metastatic sites when deciding on treatment options for metastatic RCC? How do we choose between dual immunotherapy and combinations of immunotherapy and tyrosine kinase inhibitors? This review article aims to answer these unresolved questions surrounding the concept of personalized medicine.

CaboCombo: a prospective, phase IV study of first-line cabozantinib + nivolumab for advanced renal cell carcinoma

Cabozantinib plus nivolumab was approved as a first-line (1L) treatment for advanced renal cell carcinoma (aRCC) following the CheckMate 9ER trial. CaboCombo (ClinicalTrials.gov identifier: NCT05361434) is a non-interventional study designed to evaluate the effectiveness and tolerability of cabozantinib plus nivolumab in a real-world setting. Overall, 311 patients with clear-cell aRCC receiving 1L cabozantinib plus nivolumab will be recruited from at least 70 centers in seven countries worldwide. The primary end point is overall survival at 18 months. Secondary end points include progression-free survival, objective response rate, safety, patterns of treatment, subsequent anticancer therapies and quality of life. CaboCombo will provide real-world evidence on the characteristics, treatment sequences, and outcomes of patients with aRCC receiving 1L cabozantinib plus nivolumab.

Advanced in vitro models for renal cell carcinoma therapy design

Renal cell carcinoma (RCC) and its principal subtype, clear cell RCC, are the most diagnosed kidney cancer. Despite substantial improvement over the last decades, current pharmacological intervention still fails to achieve long-term therapeutic success. RCC is characterized by a high intra- and inter-tumoral heterogeneity and is heavily influenced by the crosstalk of the cells composing the tumor microenvironment, such as cancer-associated fibroblasts, endothelial cells and immune cells. Moreover, multiple physicochemical properties such as pH, interstitial pressure or oxygenation may also play an important role. These elements are often poorly recapitulated in in vitro models used for drug development. This inadequate recapitulation of the tumor is partially responsible for the current lack of an effective and curative treatment. Therefore, there are needs for more complex in vitro or ex vivo drug screening models. In this review, we discuss the current state-of-the-art of RCC models and suggest strategies for their further development.

A Podcast Discussion on the Current Treatment Landscape for Renal Cell Carcinoma

During the last 15 years, tremendous efforts have been made in the medical treatment of metastatic renal cell carcinoma (mRCC). Immune-oncological (IO) combinations are the current standard of care in the first-line setting of mRCC. Here, the current phase 3 trials CM214 (nivolumab/ipilimumab vs. sunitinib), KN426 (axitinib/pembrolizumab vs. sunitinib), Javelin-ren-101 (axitinib/avelumab vs. sunitinib), CM9ER (cabozantinib/nivolumab vs. sunitinib), and CLEAR (lenvatinib/pembrolizumab vs. sunitinib) were discussed. In the mentioned phase 3 trials, primary and secondary endpoints were discussed. Strengths and weaknesses of each trial were reflected in terms of overall survival, progression-free survival, objective remission, health quality of life, and safety. Reflecting on the data, as well as the current ESMO guidelines, we discuss choosing the appropriate medical treatment for patients' individualized treatment journey and relay the strength and weaknesses of each combination-starting with the appropriate first-line therapy.

Insulin receptor expression to predict resistance to axitinib and elucidation of the underlying molecular mechanism in metastatic renal cell carcinoma

BACKGROUND

The study aimed to examine the significance of insulin receptor (INSR) expression in predicting resistance to axitinib in clear cell renal cell carcinoma (ccRCC).

METHODS

Clinicopathological data were collected from 36 consecutive patients with metastatic RCC who received axitinib. Thirty-three primary tumours were obtained for immunohistochemistry. Patient-derived xenograft (PDX) models were created by transplanting primary tumours into immunodeficient mice, establishing axitinib-resistant PDX models. RCC cell lines were co-cultured with human renal glomerular endothelial cells (HGECs) treated with siRNA of INSR (HGEC-siINSR). Gene expression alteration was analysed using microarray.

RESULTS

The patients with low INSR expression who received axitinib had a poorer outcome. Multivariate analysis showed that INSR expression was the independent predictor of progression-free survival. INSR expression decreased in axitinib-resistant PDX tumours. RCC cell lines showed upregulated interferon responses and highly increased interferon-β levels by co-culturing with HGEC-siINSR. HGECs showed decreased INSR and increased interferon-β after axitinib administration. RCC cell lines co-cultured with HGEC-siINSR showed high programmed death-ligand 1 (PD-L1) expression, which increased after interferon-β administration.

CONCLUSIONS

Decreased INSR in RCC could be a biomarker to predict axitinib resistance. Regarding the resistant mechanism, vascular endothelial cells with decreased INSR in RCC may secrete interferon-β and induce PD-L1.

Gene set enrichment analysis identifies immune subtypes of kidney renal clear cell carcinoma with significantly different molecular and clinical properties

Background

Kidney renal clear cell carcinoma (KIRC) is the most prevalent renal malignancy, marked by a high abundance of tumor-infiltrating lymphocytes (TILs) and an unfavorable prognosis upon metastasis. Numerous studies have demonstrated that KIRC possesses a tumor microenvironment that is highly heterogeneous, and this is associated with significant variations in the effectiveness of most first-line drugs administered to KIRC patients. Therefore, it is crucial to classify KIRC based on the tumor microenvironment, although these subtyping techniques are still inadequate.

Methods

By applying gene set enrichment scores of 28 immune signatures, we conducted a hierarchical clustering of KIRC and determined its immune subtypes. In addition, we conducted a comprehensive exploration of the molecular and clinical features of these subtypes, including survival prognosis, proliferation, stemness, angiogenesis, tumor microenvironment, genome instability, intratumor heterogeneity, and pathway enrichment.

Results

Through cluster analysis, two immune subtypes of KIRC were identified and termed Immunity-High (Immunity-H) and Immunity-Low (Immunity-L). This clustering outcome was consistent in four independent KIRC cohorts. The subtype Immunity-H exhibited elevated levels of TILs, tumor aneuploidy, homologous recombination deficiency, stemness, and proliferation potential, along with a poorer prognosis for survival. Despite this, the Immunity-L subtype demonstrated elevated intratumor heterogeneity and a stronger angiogenesis signature in contrast to Immunity-H. According to the results of pathway enrichment analysis, the Immunity-H subtype was found to be highly enriched in immunological, oncogenic, and metabolic pathways, whereas the Immunity-L subtype was highly enriched in angiogenic, neuroactive ligand-receptor interaction, and PPAR pathways.

Conclusions

Based on the enrichment of immune signatures in the tumor microenvironment, KIRC can be categorized into two immune subtypes. The two subtypes demonstrate considerably distinct molecular and clinical features. In KIRC, an increase in immune infiltration is linked to a poor prognosis. Patients with Immunity-H KIRC may exhibit active responses to PPAR and immune checkpoint inhibitors, whereas patients with Immunity-L may manifest favorable responses to anti-angiogenic agents and immune checkpoint inhibitors. The immunological classification provides molecular insights into KIRC immunity, as well as clinical implications for the management of this disease.

Patient-reported outcomes in metastatic renal cell carcinoma trials using combinations versus sunitinib as first-line treatment

Over the past 5 years, several new immunotherapy treatments have been tested for metastatic renal cell carcinoma (mRCC). Clinical trials assessing combinations of different immunotherapies, or of an immunotherapy with a tyrosine kinase inhibitor (TKI), have reported improved clinical outcomes compared with the standard of care - that is, treatments using TKIs alone. However, to understand the holistic impact of new treatments on patients, physicians must also consider effects on health-related quality of life (HRQoL). As patient-reported outcome measures (PROMs) on HRQoL are often treated as a secondary outcome in clinical trials, their collection and reporting are non-standardized and, therefore, difficult to compare and interpret. However, results from six clinical trials indicate that two immunotherapy treatments overwhelmingly outperform sunitinib in HRQoL measurements: nivolumab plus cabozantinib (CheckMate 9ER) and atezolizumab plus bevacizumab (IMmotion151). An additional two treatments generally outperform sunitinib: nivolumab plus ipilimumab (CheckMate 214) and lenvatinib plus pembrolizumab (CLEAR). Of three studies that reported no difference from sunitinib, two suffered design flaws that might have obscured HRQoL benefits (JAVELIN Renal 101 and KEYNOTE-426). To ensure future HRQoL data are of the highest quality and comparable across trials, future studies should adopt best practices for the design, analysis and reporting of PROMs.

The E3 ligase RBCK1 reduces the sensitivity of ccRCC to sunitinib through the ANKRD35-MITD1-ANXA1 axis

Despite the promise of targeted tyrosine kinase inhibitors (TKIs), such as sunitinib, in the extension of survival time in patients with clear cell renal cell carcinoma (ccRCC) progression or metastasis, the patients eventually succumb to inevitable drug resistance. Protein degradation executed by the ubiquitin-dependent proteasome system played an important role in determining the sensitivity of ccRCC to sunitinib. Here, we applied the bioinformatic analysis to identify that E3 ligase RBCK1 was elevated in the sunitinib-resistant renal cancer cell lines or patient specimens. The subsequent in vitro or in vivo studies demonstrated that RBCK1 contributed to decreasing the sensitivity of ccRCC to sunitinib. Then, we showed that inhibition of RBCK1 inactivated the AKT and MAPK signaling pathways, which might be one of the main reasons why RBCK1 induces sunitinib resistance in ccRCC cells. Mechanistically, our results indicated that RBCK1 promotes the degradation of ANKRD35 and that ANKRD35 destabilizes MITD1 by binding with SUMO2 in ccRCC cells. In addition, we showed that the RBCK1-ANKRD35-MITD1-ANXA1 axis regulates the phosphorylation of AKT and ERK and contributes to the dysregulation of sunitinib in ccRCC cells. Therefore, we identified a novel mechanism for regulating the sensitivity of sunitinib in ccRCC. Therefore, we elucidated a novel mechanism by which RBCK1 regulates sunitinib sensitivity in ccRCC.

TRB CDR3-cancer testis antigen chemical complementarity scoring for identifying productive immune responses in renal cell carcinoma

BACKGROUND

Immunogenomics approaches to the characterization of renal cell carcinoma (RCC) have helped to better our understanding of the features of RCC immune dysfunction. However, much is still unknown with regard to specific immune interactions and their impact in the tumor microenvironment.

OBJECTIVE

This study applied chemical complementarity scoring for the TRB complementarity determining region-3 (CDR3) amino acid sequences and cancer testis antigens (CTAs) to determine whether such complementarity correlated with survival and the expression of immune marker genes.

METHODS

TRB recombination reads from RCC tumor samples from RNAseq files obtained from two separate databases, Moffitt Cancer Center and The Cancer Genome Atlas (TCGA), were evaluated. Chemical complementarity scores (CSs) were calculated for TRB CDR3-CTA pairs and survival assessments based on those CSs were performed.

RESULTS

Moffitt Cancer Center and TCGA cases representing the upper 50th percentile of chemical CSs for TRB CDR3 amino acid sequences and the CTA POTEA were found to be associated with a better overall survival (OS) Also, greater tumor RNA expression of multiple immune signature genes, including granzyme A, granzyme B, and interferon-gamma were correlated with the higher chemical CSs.

CONCLUSIONS

These results indicate that TRB CDR3-CTA chemical complementarity scoring may be useful in distinguishing RCC cases with a productive, anti-tumor immune response from cases where basic immune parameter assessments are inconsistent with a productive immune response.

Comprehensive analysis to identify the RP11-478C19.2/ E2F7 axis as a novel biomarker for treatment decisions in clear cell renal cell carcinoma

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LncRNA RP11–478C19.2 promotes the progression of ccRCC via the RP11–478C19.2/hsa-miR-181b-5p, hsa-miR-181a-5p, hsa-miR-181c-5p/E2F7 axis.

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E2F7 could be detected in patients with ccRCC to aid treatment regimen selection, particularly in advanced and metastatic disease.

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Individuals who overexpress E2F7 may have a greater response to some first-line therapy for ccRCC, including cabozantinib, pazopanib, and sunitinib.

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Patients with higher expression of E2F7 may have a higher percentage of ICB responses.

Clear cell renal cell carcinoma (ccRCC), accounting for 70–80% of all renal cell carcinomas, is a common malignancy. Survival rates decrease significantly in patients with advanced and metastatic ccRCC. Furthermore, ccRCC is less responsive to radiation and chemotherapy than other cancers. Therefore, targeted therapy and immunotherapy are particularly important for ccRCC management. A growing body of literature recognizes that competitive endogenous RNA (ceRNA) regulatory networks play a crucial role in various cancers. However, the biological functions of the ceRNA network in ccRCC require further investigation. In this study, we built the ceRNA network for ccRCC using the “GDCRNATools” package. After survival analysis, the RP11–478C19.2/hsa-miR-181b-5p, hsa-miR-181a-5p, and hsa-miR-181c-5p/E2F7 axes were obtained for further analysis. Unsupervised clustering was conducted basing on this ceRNA network. The results indicated that the prognosis and immune infiltration levels differed between the two clusters. Furthermore, we conducted correlation analysis, immune infiltration analysis, tumor mutation burden analysis, GSEA analysis, drug sensitivity analysis and pan-cancer analysis of E2F7 to explore its potential role in oncogenesis. Experiments in vitro were performed to confirm the pro-oncogenic impact of E2F7. The results suggest that the RP11–478C19.2/E2F7 axis might be a biomarker for the inclusion of cabozantinib, pazopanib, sunitinib, and immunotherapy in the therapeutic regimen. In summary, we found that the ceRNA-based RP11–478C19.2/E2F7 axis is involved in ccRCC and that it could be a novel biomarker for treatment decisions and a possible therapeutic target to increase the success of targeted therapy and immunotherapy in ccRCC.

YTHDC1 is downregulated by the YY1/HDAC2 complex and controls the sensitivity of ccRCC to sunitinib by targeting the ANXA1-MAPK pathway

BACKGROUND

Tyrosine kinase inhibitors (TKIs) such as sunitinib are multitarget antiangiogenic agents in clear cell renal cell carcinoma (ccRCC). They are widely used in the treatment of advanced/metastatic renal cancer. However, resistance to TKIs is common in the clinic, particularly after long-term treatment. YTHDC1 is the main nuclear reader protein that binds with m6A to regulate the splicing, export and stability of mRNA. However, the specific role and corresponding mechanism of YTHDC1 in renal cancer cells are still unclear.

METHODS

The Cancer Genome Atlas (TCGA) dataset was used to study the expression of YTHDC1 in ccRCC. Cell counting kit-8 (CCK-8), wound healing, Transwell and xenograft assays were applied to explore the biological function of YTHDC1 in ccRCC. Western blot, quantitative real time PCR (RT‒qPCR), RNA immunoprecipitation PCR (RIP-qPCR), methylated RIP-qPCR (MeRIP-qPCR) and RNA sequencing (RNA-seq) analyses were applied to study the YY1/HDAC2/YTHDC1/ANXA1 axis in renal cancer cells. The CCK-8 assay and xenograft assay were used to study the role of YTHDC1 in determining the sensitivity of ccRCC to sunitinib.

RESULTS

Our results demonstrated that YTHDC1 is downregulated in ccRCC tissues compared with normal tissues. Low expression of YTHDC1 is associated with a poor prognosis in patients with ccRCC. Subsequently, we showed that YTHDC1 inhibits the progression of renal cancer cells via downregulation of the ANXA1/MAPK pathways. Moreover, we also showed that the YTHDC1/ANXA1 axis modulates the sensitivity of tyrosine kinase inhibitors. We then revealed that HDAC2 inhibitors resensitize ccRCC to tyrosine kinase inhibitors through the YY1/HDAC2 complex. We have identified a novel YY1/HDAC2/YTHDC1/ANXA1 axis modulating the progression and chemosensitivity of ccRCC.

CONCLUSION

We identified a novel YY1/HDAC2/YTHDC1/ANXA1 axis modulating the progression and chemosensitivity of ccRCC.

Tivozanib in relapsed or refractory advanced renal cell carcinoma: a focus on US approval

INTRODUCTION

Tivozanib is a selective vascular endothelial growth factor receptor (VEGFR)-inhibitor designed to, more specifically, bind to the VEGF receptor with fewer off-target interactions with other tyrosine kinase receptors in the treatment of advanced renal cell carcinoma (RCC).

AREAS COVERED

Both preclinical and early clinical studies have suggested tivozanib could be a more potent VEGFR inhibitor with less off-target toxicities for patients. After a complicated clinical development process, the drug was approved by the FDA for third- and fourth-line use in relapsed, refractory renal cell carcinoma (RCC) in March of 2021 based on the results of the TIVO-3 trial. However, questions remain regarding the proper incorporation of tivozanib in the current treatment landscape of RCC.

EXPERT OPINION

Here, we review the existing literature surrounding tivozanib and comment on its optimal use in current and future clinical practice. We suggest that tivozanib may be considered in relapsed, refractory RCC in the later-line treatment setting following progression on both immune checkpoint inhibitors (ICIs) and nonselective VEGFR-TKIs. We anticipate the application of tivozanib in RCC will continue to evolve as trials exploring tivozanib in combination with ICIs may move this drug earlier in the future treatment landscape of RCC.

Evaluation of mild cognitive impairment and dementia in patients with metastatic renal cell carcinoma

BACKGROUND

Dementia and cancer are both more common in adults as they age. As new cancer treatments become more popular, it is important to consider how these treatments might affect older patients. This study evaluates metastatic renal cell carcinoma (mRCC) as a risk factor for older adults developing mild cognitive impairment or dementia (MCI/D) and the impact of mRCC-directed therapies on the development of MCI/D.

METHODS

We identified patients diagnosed with mRCC in a Surveillance, Epidemiology, and End Results (SEER)-Medicare dataset from 2007 to 2015 and matched them to non-cancer controls. Exclusion criteria included age < 65 years at mRCC diagnosis and diagnosis of MCI/D within the year preceding mRCC diagnosis. The main outcome was time to incident MCI/D within one year of mRCC diagnosis for cases or cohort entry for non-cancer controls. Cox proportional hazards models were used to measure associations between mRCC and incident MCI/D as well as associations of oral anticancer agent (OAA) use with MCI/D development within the mRCC group.

RESULTS

Patients with mRCC (n = 2533) were matched to non-cancer controls (n = 7027). mRCC (hazard ratio [HR] 8.52, p < .001), being older (HR 1.05 per 1-year age increase, p < .001), and identifying as Black (HR 1.92, p = .047) were predictive of developing MCI/D. In addition, neither those initiating treatment with OAAs nor those who underwent nephrectomy were more likely to develop MCI/D.

CONCLUSIONS

Patients with mRCC were more likely to develop MCI/D than those without mRCC. The medical and surgical therapies evaluated were not associated with increased incidence of MCI/D. The increased incidence of MCI/D in older adults with mRCC may be the result of the pathology itself or risk factors common to the two disease processes.

Overexpression of TP53INP2 Promotes Apoptosis in Clear Cell Renal Cell Cancer via Caspase-8/TRAF6 Signaling Pathway

Clear cell renal cell cancer (ccRCC) is a tumor of high malignancy, which can escape apoptosis. The tumor protein p53-inducible nuclear protein 2 (TP53INP2), known as an autophagy protein, is the essential part for autophagosome formation and sensitizes cells to apoptosis. Our study is aimed at exploring the role of TP53INP2 in ccRCC. We have identified the autophagy-related genes (ARGs) of differential expression in ccRCC patients with the help of the TCGA database by bioinformatics analysis. Our assays of quantitative real-time polymerase chain reaction (qRT-PCR) and western blot were for the determination on the both levels of mRNA and protein. Overexpression of TP53INP2 on cellular proliferation, migration, and apoptosis of ccRCC was verified in the ways of performing CCK-8, wound scrape, transwell and flow cytometry assays in vitro, and a mice tumor model in vivo. Transmission electron microscopy was used to measure autophagy formation. The underlying mechanisms of TP53INP2 on ccRCC were determined via coimmunoprecipitation. TP53INP2 was found highly associated with an outcome of worse overall survival (OS) in Kaplan-Meier curves, and this parameter in ccRCC tissues was also lower than the normal tissues. Overexpression of TP53INP2 inhibited ccRCC cellular proliferation, migration, and invasion, as well as the tumor growth of mice. Those cells treated with autophagy inhibitor chloroquine (CQ) or TP53INP2 increased the apoptosis rate. TP53INP2 promoted autophagy formation and elevated the ratio of LC3 II/LC3 I. However, TP53INP2 did not significantly decrease the p-mTOR level. In addition, TP53INP2 activates the expressions of caspase-3, caspase-8, and PARP. Caspase-8 and TNF receptor associated factor 6 (TRAF6) were found to bind to each other in the presence of TP53INP2. TP53INP2 induces apoptosis in ccRCC cells through caspase-8/TRAF6 pathway, rather than the autophagy-dependent pathway.

Front-Line Therapy for Metastatic Renal Cell Carcinoma: A Perspective on the Current Algorithm and Future Directions

Over the last decade, the treatment paradigm of metastatic renal cell carcinoma has rapidly evolved, with notable changes in the front-line setting. Combination therapies involving the use of either doublet therapy with immune checkpoint inhibitors or combination VEGFR-directed therapies with immune checkpoint inhibitors have significantly improved clinical outcomes, including prolonged overall survival and durable response to treatment. We aim to highlight the Food and Drug Administration-approved front-line therapy options, the navigation of treatment selection, and the future directions of metastatic renal cell carcinoma therapies.

Approaches to First-Line Therapy for Metastatic Clear Cell Renal Cell Carcinoma

PURPOSE OF REVIEW

Four immuno-oncology (IO)-based combinations have demonstrated overall survival benefit as frontline treatment of metastatic clear cell renal cell carcinoma (mccRCC). Choosing among the available combinations depends on treating physician's interpretation of existing data without level I evidence to inform choice of therapy. Landmark trials of mccRCC are reviewed and perspective on treatment options is provided.

RECENT FINDINGS

The four IO-based combinations reviewed are ipilimumab/nivolumab (IO/IO), pembrolizumab/axitinib (IO/TKI), nivolumab/cabozantinib (IO/TKI), and pembrolizumab/lenvatinib (IO/TKI). The ipilimumab/nivolumab combination is notable for durable efficacy after extended 4-year follow-up. IO/TKI combinations have clinical efficacy across all IMDC risk groups with higher response rates and longer progression-free survival (PFS) but also had higher ≥ grade 3 adverse events rate. Patient tumor burden, performance status, and IMDC risk group are factors in choosing an IO-based treatment. IO/IO and IO/TKI combinations for mccRCC have distinct efficacy and toxicity profiles. Future studies are needed to identify biomarkers to optimize patient outcomes.

CaboPoint: a phase II study of cabozantinib as second-line treatment in patients with metastatic renal cell carcinoma

Cabozantinib is an inhibitor of multiple tyrosine kinases, including AXL, MET and VEGF receptors. Here, we describe the rationale and design for the phase II CaboPoint trial (ClinicalTrials.gov identifier: NCT03945773), which will evaluate the efficacy and safety of cabozantinib as a second-line treatment in patients with unresectable, locally advanced or metastatic renal cell carcinoma whose disease has progressed despite checkpoint inhibitor therapy. Patients will be recruited into two cohorts: prior ipilimumab plus nivolumab (cohort A) or prior checkpoint inhibitor-VEGF-targeted therapy (cohort B). All patients will receive once-daily oral cabozantinib 60 mg for up to 18 months. The primary end point is objective response rate. Secondary end points include overall survival, progression-free survival and safety.

Pharmacometabolomics Applied to Personalized Medicine in Urological Cancers

Prostate cancer (PCa), bladder cancer (BCa), and renal cell carcinoma (RCC) are the most common urological cancers, and their incidence has been rising over time. Surgery is the standard treatment for these cancers, but this procedure is only effective when the disease is localized. For metastatic disease, PCa is typically treated with androgen deprivation therapy, while BCa is treated with chemotherapy, and RCC is managed primarily with targeted therapies. However, response rates to these therapeutic options remain unsatisfactory due to the development of resistance and treatment-related toxicity. Thus, the discovery of biomarkers with prognostic and predictive value is needed to stratify patients into different risk groups, minimizing overtreatment and the risk of drug resistance development. Pharmacometabolomics, a branch of metabolomics, is an attractive tool to predict drug response in an individual based on its own metabolic signature, which can be collected before, during, and after drug exposure. Hence, this review focuses on the application of pharmacometabolomic approaches to identify the metabolic responses to hormone therapy, targeted therapy, immunotherapy, and chemotherapy for the most prevalent urological cancers.

Immune checkpoint inhibitors rechallenge in urological tumors: An extensive review of the literature

Immune checkpoint inhibitors (ICIs) have led to a significant change in the treatment of urological tumors where several agents are currently approved. Yet, most patients discontinue treatment due to disease progression or after the onset of severe immune-related adverse events (IRAEs). Following promising results in melanoma patients, retreatment with an ICI is receiving increasing attention as an attractive option for selected patients. We performed a literature review focusing on the feasibility, safety, timing and activity of ICI rechallenge in genitourinary cancers where very little information is available. We classified the different ICI retreatment strategies into three main clinical scenarios: retreatment after terminating a prior course of ICI while still on response; retreatment after interruption due to IRAEs; retreatment after progression while on ICI therapy. The pros and cons of these options in the field of urological tumors are then discussed, and critical suggestions proffered for the design of future clinical trials.

Prognostic Impact of Lymphnode Metastases in Patients with Metastatic Renal Cell Carcinoma

BACKGROUND: Lymphnode metastases (LMN) in metastatic renal cell carcinoma (mRCC) has been associated with an unfavourable prognosis. However, the prognostic impact of LNM in mRCC in context of other solid organ metastases and throughout subsequent therapeutic lines is not well-defined. OBJECTIVE: This retrospective single-center analysis was designed to elucidate the impact of LNM in the context of other solid organ metastases and throughout subsequent therapeutic lines. METHODS: mRCC patients (pts) at our center were analysed (observation period, 04/00-03/16). Primary endpoint was overall survival (OS) and the impact of line of therapy as a co-variate. Pts were grouped into: with LNM [LNM(+)], without LNM [LNN(–)]. Subgroup analyses of LNM(+) was performed including the subgroup LNM(+) and other solid organ metastases [LNM(+) other] and LNM(+) without other solid organ metastases [LMN(+) only]. RESULTS: 383/401 mRCC pts were eligible. 318 (83.2%), 230 (60.1%) and 154 (40.5%) pts received 1stL, 2ndL and 3rdL medical treatment, respectively. In the overall population OS was 40.1 months (95%CI: 32.7–47.4), with superior OS in LNM(–) compared to LNM(+) pts (log rank, HR 1.7, 95%-CI 1.3-2.2, p < 0.001). This effect was maintained across lines of therapies. LNM(+) only had a similar risk of death as LNM(–) pts (HR 1.2, 95%-CI 0.8–2.0, p = 0.4), while the risk of death was significantly increased for LNM(+) other compared to LNM(–) (HR 1.9, 95%-CI 1.5–2.6, p < 0.001). CONCLUSION: LNM(+) in mRCC is associated with a poor OS. However, impaired OS in LNM(+) might be associated with the presence of other solid organ metastases rather than with the existence of LNM alone. Further studies are warranted to support this hypothesis.

Antiangiogenic Properties of Axitinib versus Sorafenib Following Sunitinib Resistance in Human Endothelial Cells-A View towards Second Line Renal Cell Carcinoma Treatment

Tyrosine kinase inhibitors (TKIs) and immune checkpoint inhibitors predominate as first-line therapy options for renal cell carcinoma. When first-line TKI therapy fails due to resistance development, an optimal second-line therapy has not yet been established. The present investigation is directed towards comparing the anti-angiogenic properties of the TKIs, sorafenib and axitinib on human endothelial cells (HUVECs) with acquired resistance towards the TKI sunitinib. HUVECs were driven to resistance by continuously exposing them to sunitinib for six weeks. They were then switched to a 24 h or further six weeks treatment with sorafenib or axitinib. HUVEC growth, as well as angiogenesis (tube formation and scratch wound assay), were evaluated. Cell cycle proteins of the CDK-cyclin axis (CDK1 and 2, total and phosphorylated, cyclin A and B) and the mTOR pathway (AKT, total and phosphorylated) were also assessed. Axitinib (but not sorafenib) significantly suppressed growth of sunitinib-resistant HUVECs when they were exposed for six weeks. This axinitib-associated growth reduction was accompanied by a cell cycle block at the G0/G1-phase. Both axitinib and sorafenib reduced HUVEC tube length and prevented wound closure (sorafenib > axitinib) when applied to sunitinib-resistant HUVECs for six weeks. Protein analysis revealed diminished phosphorylation of CDK1, CDK2 and pAKT, accompanied by a suppression of cyclin A and B. Both drugs modulated CDK-cyclin and AKT-dependent signaling, associated either with both HUVEC growth and angiogenesis (axitinib) or angiogenesis alone (sorafenib). Axitinib and sorafenib may be equally applicable as second line treatment options, following sunitinib resistance.

First-Line Treatment of Metastatic Clear Cell Renal Cell Carcinoma: What Are the Most Appropriate Combination Therapies?

The development of antiangiogenic treatments, followed by immune checkpoint inhibitors (ICI), has significantly changed the management of metastatic clear cell renal cell cancer. Several phase III trials show the superiority of combination therapy, dual immunotherapy (ICI-ICI) or ICI plus tyrosine kinase inhibitors (TKI) of the vascular endothelium growth factor (VEGF) over sunitinib monotherapy. The question is therefore what is the best combination for a given patient? A strategy based on the International Metastatic Database Consortium (IMDC) classification is currently recommended with pembrolizumab + axitinib, cabozantinib + nivolumab, and lenvatinib + pembrolizumab (for all patients) or nivolumab + ipilimumab (for patients with intermediate or poor risk), which are the first-line treatment standards of care. However, several issues remain unresolved and require further investigation, such as the PD-L1 status, the relevance of possible options based on the patient's profile, and consideration of second-line and subsequent treatments.

Safety and Efficacy of Tivozanib in First-Line mRCC: A Multicenter Compassionate-Use Study (Meet-Uro 16)

INTRODUCTION

Tivozanib is a potent and selective tyrosine kinase inhibitor of vascular endothelial growth factor receptor 1 (VEGFR-1), VEGFR-2, and VEGFR-3, recently approved in Europe for the first-line treatment of metastatic renal cell carcinoma (mRCC).

METHODS

Retrospective analysis of safety and activity of tivozanib administered at 1.34 mg daily (3 weeks on, 1 week off) within a compassionate-use program to patients with mRCC with no prior systemic treatment in Italy.

RESULTS

From August 2018 to April 2019, 64 patients have started tivozanib in 9 oncology units. The median age was 67.5 years (range 40-85), 62.5% males. According to International Metastatic Renal Cell Carcinoma Database Consortium criteria, 27.1% of patients were good prognosis, 57.6% intermediate, and 15.3% poor. Primary tumor had been removed in 71.9% of patients. Histology was clear cell 89%, papillary 4.7%, and unclassified 6.3%. The response rate was 34.4%, stable disease 40.6%, and progression 15.6%. Grade 3-4 toxicities were 7.8% hypertension, 4.7% anemia, 3.1% mucositis, 3.1% asthenia, 1.6% diarrhea, 1.6% anorexia, 1.6% worsening of renal function, and 3.1% cardiac events. Dose reduction to 0.89 mg was applied to 17.2% of patients, and the discontinuation rate due to toxicity was 5.8%. Median progression-free survival was 12.4 months, with 68.7% of patients alive at 12 months. The developing of hypertension predicted increased progression-free survival at multivariate analysis (HR, 0.128; 95% CI, 0.03-0.59; p = 0.008).

CONCLUSIONS

Tivozanib showed good activity and favorable safety profile in a real-world cohort of unselected patients with mRCC. Predictive biomarkers of response to antiangiogenic therapy are urgently needed in order to identify RCC patients who could still receive a monotherapy with VEGFR inhibitors in the first line.

New approaches to first-line treatment of advanced renal cell carcinoma

The treatment of patients with renal cell carcinoma (RCC) is evolving rapidly, with promising new regimens being developed and approved for patients with advanced disease, particularly the combination of tyrosine kinase inhibitors with immune checkpoint inhibitors. Within the last 6 months, favorable first-line setting results for patients with clear cell RCC have been reported for the combination of cabozantinib plus nivolumab in the phase III CheckMate 9ER study, leading to its regulatory approval, and lenvatinib plus pembrolizumab in the phase III CLEAR study. Additional systemic first-line treatments for clear cell RCC include axitinib plus pembrolizumab, pazopanib, and sunitinib for favorable-risk patients and ipilimumab plus nivolumab, axitinib plus pembrolizumab, axitinib plus avelumab, and cabozantinib for intermediate- or poor-risk patients. In this review of novel approaches for first-line treatment of advanced RCC, we present an overview of current treatment strategies, the basis behind emerging treatment approaches, a summary of key results from the pivotal studies using tyrosine kinase inhibitor and immune checkpoint inhibitor combination therapy, novel treatments and strategies under development, and efforts for identifying biomarkers to guide treatment decisions.

Association of tumor burden with outcome in first-line therapy with nivolumab plus ipilimumab for previously untreated metastatic renal cell carcinoma

OBJECTIVES

To investigate the prognostic impact of tumor burden in patients receiving nivolumab plus ipilimumab as first-line therapy for previously untreated metastatic renal cell carcinoma (mRCC).

METHODS

We retrospectively evaluated 62 patients with IMDC intermediate- or poor-risk mRCC, treated with nivolumab plus ipilimumab as first-line therapy at five affiliated institutions. Tumor burden was defined as the sum of diameters of baseline targeted lesions according to the RECIST version.1.1. We categorized the patients into two groups based on the median value of tumor burden (i.e., high vs. low). The association of tumor burden with progression-free survival (PFS), overall survival (OS) and objective response rate (ORR) with nivolumab plus ipilimumab treatment was analyzed.

RESULTS

The median tumor burden was 63.0 cm (interquartile range: 34.2-125.8). PFS was significantly shorter in patients with high tumor burden (n = 31) than in those with low tumor burden (n = 31) (median: 6.08 [95% CI: 2.73-9.70] vs. 12.5 [4.77-24.0] months, P = 0.0134). In addition, OS tended to be shorter in patients with high tumor burden; however, there was no statistically significant difference (1-year rate: 77.3 vs. 96.7%, P = 0.166). ORR was not significantly different between patients with high and low tumor burden (35 vs. 55%, P = 0.202). Multivariate analysis of PFS further showed that tumor burden was an independent factor (HR: 2.22 [95% CI: 1.11-4.45], P = 0.0242).

CONCLUSIONS

Tumor burden might be a useful factor for outcome prediction, at least for PFS prediction, in patients receiving nivolumab plus ipilimumab for mRCC. Further prospective studies are warranted to confirm our findings.

An up-to-date evaluation of cabozantinib for the treatment of renal cell carcinoma

Introduction: In the evolving treatment scenario of metastatic renal cell carcinoma, cabozantinib is gaining increasing attention, presenting as a cornerstone therapy, both as a monotherapy and in combination with immune-checkpoint inhibitors.Areas covered: In this review, the authors explore the role of cabozantinib in the treatment of metastatic clear cell and non-clear cell renal cell carcinoma, presenting data from the most recent clinical trials and investigating ongoing studies. They, furthermore, evaluate the pharmacokinetic, pharmacodynamic, and immunomodulatory effect of cabozantinib, as well as underlining the tolerability profile and patients' quality of life.Expert opinion: Cabozantinib's administration as a single agent is restricted to intermediate- and poor-risk patients (according to IMDC criteria). The further advent of anti-VEGF-receptor tyrosine kinase inhibitors combined with immune checkpoint inhibitor regimens (such as pembrolizumab + axitinib) has allowed to expand the use of cabozantinib, leading to its combination with nivolumab. In the next few years, more information is required to look for the application of cabozantinib-based combinations as a later-line approach in metastatic RCC patients, beside their use in the first-line setting.

Altered proTGFα/cleaved TGFα ratios offer new therapeutic strategies in renal carcinoma

BACKGROUND

Treatment of renal cancer has significantly improved with the arrival to the clinic of kinase inhibitors and immunotherapies. However, the disease is still incurable in advanced stages. The fact that several approved inhibitors for kidney cancer target receptor tyrosine kinases (RTKs) suggests that these proteins play a critical role in the pathophysiology of the disease. Based on these precedents, we decided to explore whether RTKs other than those targeted by approved drugs, contribute to the development of kidney cancer.

METHODS

The activation status of 49 RTKs in 44 paired samples of normal and tumor kidney tissue was explored using antibody arrays, with validation by western blotting. Genetic and pharmacologic approaches were followed to study the biological implications of targeting the epidermal growth factor receptor (EGFR) and its ligand Transforming Growth Factor-α (TGFα).

RESULTS

Activation of the EGFR was found in a substantial number of tumors. Moreover, kidney tumors expressed elevated levels of TGFα. Down-regulation of EGFR or TGFα using RNAi or their pharmacological targeting with blocking antibodies resulted in inhibition of the proliferation of in vitro cellular models of renal cancer. Importantly, differences in the molecular forms of TGFα expressed by tumors and normal tissues were found. In fact, tumor TGFα was membrane anchored, while that expressed by normal kidney tissue was proteolytically processed.

CONCLUSIONS

The EGFR-TGFα axis plays a relevant role in the pathophysiology of kidney cancer. This study unveils a distinctive feature in renal cell carcinomas, which is the presence of membrane-anchored TGFα. That characteristic could be exploited therapeutically to act on tumors expressing transmembrane TGFα, for example, with antibody drug conjugates that could recognize the extracellular region of that protein.

Prognostic Impact of Early Treatment Interruption of Nivolumab Plus Ipilimumab Due to Immune-Related Adverse Events as First-Line Therapy for Metastatic Renal Cell Carcinoma: A Multi-Institution Retrospective Study

BACKGROUND

It remains unclear how early treatment interruption of nivolumab plus ipilimumab due to immune-related adverse events affects the outcome of previously untreated metastatic renal cell carcinoma (mRCC).

OBJECTIVE

To investigate the prognostic impact of the early interruption of nivolumab plus ipilimumab, used as first-line therapy for mRCC.

PATIENTS AND METHODS

We retrospectively evaluated 59 intermediate- or poor-risk mRCC patients who received nivolumab plus ipilimumab as first-line therapy. Based on whether early treatment interruption was implemented within the initial four treatment cycles (i.e., 3 months) or not, progression-free survival (PFS), overall survival (OS), and objective response rate (ORR) were compared. The prognostic association was further compared with that of 186 patients treated with tyrosine kinase inhibitors (TKIs) as first-line therapy.

RESULTS

Twenty-three of the 59 patients (39%) experienced interruption of nivolumab plus ipilimumab therapy. The patients with interruption had longer PFS (p = 0.0055), similar OS (p = 0.366), and likely higher ORR (p = 0.0660) than those without interruption. Of the patients treated with TKIs, 60 of 186 (32%) experienced interruption, with shorter PFS (p = 0.0121), similar OS (p = 0.378), and similar ORR (p = 0.738) than those without interruption. In the 23 patients with nivolumab plus ipilimumab interruption, high-dose corticosteroids were administered in seven patients (30%). PFS (p = 0.638), OS (p = 0.968), or ORR (p = 0.760) did not differ based on corticosteroid administration.

CONCLUSIONS

Early treatment interruption, which exerted a negative effect for TKIs, was a preferable event for nivolumab plus ipilimumab when considering PFS. Furthermore, early administration of high-dose corticosteroids did not diminish the anti-tumor effect of nivolumab plus ipilimumab.

Prognostic Role of Circulating Tumor Cells in Metastatic Renal Cell Carcinoma: A Large, Multicenter, Prospective Trial

BACKGROUND

Circulating tumor cells (CTCs) correlate with adverse prognosis in patients with breast, colorectal, lung, and prostate cancer. Little data are available for renal cell carcinoma (RCC).

MATERIALS AND METHODS

We designed a multicenter prospective observational study to assess the correlation between CTC counts and progression-free survival (PFS) in patients with metastatic RCC treated with an antiangiogenic tyrosine kinase inhibitor as a first-line regimen; overall survival (OS) and response were secondary objectives. CTC counts were enumerated by the CellSearch system at four time points: day 0 of treatment, day 28, day 56 and then at progression, or at 12 months in the absence of progression.

RESULTS

One hundred ninety-five eligible patients with a median age of 69 years were treated with sunitinib (77.5%) or pazopanib (21%). At baseline, 46.7% of patients had one or more CTCs per milliliter (range, 1 to 263). Thirty patients had at least three CTCs, with a median PFS of 5.8 versus 15 months in the remaining patients (p = .002; hazard ratio [HR], 1.99), independently of the International Metastatic RCC Database Consortium score at multivariate analysis (HR, 1.91; 95% confidence interval [CI], 1.16-3.14). Patients with at least three CTCs had a shorter estimated OS of 13.8 months versus 52.8 months in those with fewer than three CTCs (p = .003; HR, 1.99; multivariate analysis HR, 1.67; 95% CI, 0.95-2.93). Baseline CTC counts did not correlate with response; neither did having CTC sequencing counts greater than or equal to one, two, three, four, or five.

CONCLUSION

We provide prospective evidence that the presence of three or more CTCs at baseline is associated with a significantly shorter PFS and OS in patients with metastatic RCC.

IMPLICATIONS FOR PRACTICE

This prospective study evaluated whether the presence of circulating tumor cells (CTCs) in the peripheral blood correlates with activity of first-line tyrosine kinase inhibitors in metastatic renal cell carcinoma (RCC). This study demonstrated that almost half of patients with metastatic RCC have at least one CTC in their blood and that those patients with at least three CTCs are at increased risk of early progressive disease and early death due to RCC. Studies incorporating CTC counts in the prognostic algorithms of metastatic RCC are warranted.

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.