Immune Checkpoint Inhibitors in the Treatment of Renal Cell Carcinoma

Biomimetic Copper Nanozyme Reprograms Cold Tumor via Cuproptosis-Pyroptosis Crosstalk for Potent Renal Carcinoma Immunotherapy

Immune checkpoint blockade (ICB) therapy is an emerging strategy for renal cell carcinoma (RCC). However, its clinical efficacy remains constrained by its inherently poor immunogenicity and insufficient cytotoxic T lymphocyte (CTL) infiltration. Herein, we engineer a biomimetic copper nanozyme (Cu2O-OMV) by integrating Cu2O nanoparticles with bacterial outer-membrane vesicles (OMVs) to activate the antitumor immune response and synergize with ICB therapy. The Cu2O-OMV nanozyme exhibits peroxidase (POD)-like catalytic activity and releases Cu+ to exert Fenton-like activity, generating cytotoxic hydroxyl radicals (·OH) for tumor inhibition. Furthermore, Cu+ accumulation promotes the occurrence of cuproptosis, leading to the mitochondrial aggregation of lipoylated dihydrolipoamide S-acetyltransferase and depletion of ferredoxin 1. Notably, Cu2O-OMV concurrently activates pyroptosis via the noncanonical inflammasome pathway through its intrinsic lipopolysaccharide cargo, directly inhibiting tumor growth and inducing inflammatory cytokine release. The coordinated induction of cuproptosis and pyroptosis synergistically amplifies immunogenic cell death to enhance tumor immunogenicity, thereby promoting dendritic cell maturation and CTL infiltration. After combining with αPD-L1, it effectively destroys tumor cells to activate the antitumor immune response, thereby inhibiting tumor metastasis. Our study demonstrates a biomimetic nanozyme-driven strategy that harnesses dual cuproptosis-pyroptosis pathways to enhance the tumor immunogenicity and amplify the ICB efficacy, offering a transformative approach for RCC immunotherapy.

The gut microbiome and dietary metabolites in the treatment of renal cell carcinoma

The gut microbiome is interlinked with renal cell carcinoma (RCC) and its response to systemic treatment. Mounting data suggests that certain elements of the gut microbiome may correlate with improved outcomes. New generation sequencing techniques and advanced bioinformatic data curation are accelerating the investigation of specific markers and metabolites that could predict treatment response. A variety of new therapeutic strategies, such as fecal microbiota transplantation, probiotic supplements, and dietary interventions, are currently being developed to modify the gut microbiome and improve anticancer therapies in patients with RCC. This review discusses the preliminary evidence indicating the role of the microbiome in cancer treatment, the techniques and tools necessary for its proper study and some of the current forms with which the microbiome can be modulated to improve patient outcomes.

Tivozanib Monotherapy in the Frontline Setting for Patients with Metastatic Renal Cell Carcinoma and Favorable Prognosis

PURPOSE OF REVIEW

In this review, we discuss which patients with metastatic clear cell renal cell carcinoma (mRCC) may be most suitable for frontline tyrosine kinase inhibitor (TKI) monotherapy, a treatment option supported by emerging long-term efficacy data including overall survival and quality of life. We specifically focus on tivozanib, a potent and selective inhibitor of vascular endothelial growth factor receptor, which has comparable efficacy to other single-agent TKIs in frontline treatment for mRCC while exhibiting fewer off-target side effects.

RECENT FINDINGS

Combination therapy with TKIs and checkpoint inhibitors (CPIs) and CPI/CPI combination therapies, as well as TKI monotherapy are recommended frontline treatment options for mRCC. Treatment decisions are complex and based on several factors, including the patient's International Metastatic RCC Database Consortium risk status, age, comorbidities, and personal preferences related to response, tolerability, and quality of life. TKIs not only serve as backbone of most combination therapies for mRCC, but also remain a viable monotherapy option in the first-line setting for patients in favorable risk groups and those with contraindications to CPI combination therapies. Given that overall survival benefits have not yet been confirmed for CPI-containing combination regimens in favorable risk patients, we argue that frontline single-agent TKI treatment remains a standard of care option for these patients. This is supported by treatment guidelines, even in the era of TKI/CPI combination therapies.

Research progress of MUC1 in genitourinary cancers

MUC1 is a highly glycosylated transmembrane protein with a high molecular weight. It plays a role in lubricating and protecting mucosal epithelium, participates in epithelial cell renewal and differentiation, and regulates cell adhesion, signal transduction, and immune response. MUC1 is expressed in both normal and malignant epithelial cells, and plays an important role in the diagnosis, prognosis prediction and clinical monitoring of a variety of tumors and is expected to be a new therapeutic target. This article reviews the structural features, expression regulation mechanism, and research progress of MUC1 in the development of genitourinary cancers and its clinical applications.

Immunotherapy of Clear-Cell Renal-Cell Carcinoma

Clear-cell Renal-Cell Carcinoma (ccRCC) is the most common type of renal-cell carcinoma (RCC). In many cases, RCC patients manifest the first symptoms during the advanced stage of the disease. For this reason, immunotherapy appears to be one of the dominant treatments to achieve a resolution. In this review, we focus on the presentation of the main immune checkpoint proteins that act as negative regulators of immune responses, such as PD-1, CTLA-4, LAG-3, TIGIT, and TIM-3, and their respective inhibitors. Interleukin-2, another potential component of the treatment of ccRCC patients, has also been covered. The synergy between several immunotherapies is one of the main aspects that unites the conclusions of research in recent years. To date, the combination of several immunotherapies enhances the efficacy of a monotherapy, which often manifests important limitations. Immunotherapy aimed at restoring the anti-cancer immune response in ccRCC, involved in the recognition and elimination of cancer cells, may also be a valid solution for many other types of immunogenic tumors that are diagnosed in the final stages.

Real-World Treatment Patterns and Effectiveness of Patients With Advanced Renal Cell Carcinoma: A Nationwide Observational Study

BACKGROUND

Treatment landscape for advanced renal cell carcinoma (aRCC) has evolved quickly and few data about the real-world treatment patterns are available. This study aimed at describing the real-world treatment patterns and effectiveness of all systemic treatments available for aRCC in first and second-line treatment.

MATERIALS AND METHODS

A cohort of patients initiating a first-line systemic treatment for aRCC in 2016 was extracted from the French nationwide healthcare insurance system database (SNDS). The first-line treatment initiation date constituted the index date and patients were followed until death, loss to follow-up, or December 31, 2019, whichever occurred first. aRCC was identified using hospital diagnosis, long-term disease, or renal biopsy before index date. All analyses were performed for first and second-line treatment. Overall survival (OS) and time-to-next treatment or death (TNT-D) were estimated using Kaplan-Meier approach.

RESULTS

In 2016, 1629 patients initiated a first-line treatment for aRCC. Most of them were male (75.9%) and the median age was 67 years. Most of patients (91.7%) had received a tyrosine kinase inhibitor as first-line treatment, mainly sunitinib (64.4%), and 53.5% received a second-line, among which 43.7% nivolumab. Median OS (95% confidence interval [CI]) was 20.7 (95% CI:18.2-22.4) months from first-line treatment initiation and 15.4 (13.9-17.5) months from second-line treatment initiation. Median TNT-D were respectively 9.3 (9.7-12.1) months and 6.9 (5.9-7.7) months.

CONCLUSION

This study highlights the limited survival of aRCC patients These results provide a valuable baseline and highlight the need for innovation, such as immune checkpoint inhibitor-based combinations that have recently became first-line standard of care.

15 years of patient-reported outcomes in clinical trials leading to GU cancer drug approvals: a systematic review on the quality of data reporting and analysis

Background

Standardized, high-quality PRO data reporting is crucial for patient centered care in the field of oncology, especially in clinical trials that establish standard of care. This study evaluated PRO endpoint design, conduct and reporting methods in FDA approved drugs for GU malignancies.

Methods

A systematic review of the FDA archives identified GU cancer drug approvals from Feb 2007 to July 2022. ClinicalTrials.gov and PubMed were used to retrieve relevant data. PRO data was screened, and analytic tools, interpretation methods in the published papers and study protocols were reviewed. Compliance with PRO reporting standards were assessed using PRO Endpoint Analysis Score (PROEAS), a 24-point scoring scale from Setting International Standards in Analyzing Patient-Reported Outcomes and Quality of Life Endpoints Data Consortium (SISAQOL).

Findings

We assessed 40 trial protocols with 27,011 participants, resulting in 14 renal cell cancer (RCC), 16 prostate cancer (PC), and 10 urothelial cancer (UC) approvals. PRO data was published for 27 trials, with 23 PRO publications (85%) focusing solely on PRO data, while 4 (15%) included PRO data in the original paper. Median time between primary clinical and secondary paper with PRO data was 10.5 months (range: 9-25 months). PROs were not planned as primary endpoints for any study but 14 (52%) reported them as secondary, 10 (37%) as exploratory outcomes, and 3 (11%) lacked any clarity on PRO data as endpoint. Mean PROEAS score of all GU cancers was 11.10 (range: 6-15), RCC (11.86, range: 6-15), UC (11.50, range: 9-14), and PC (10.56, range: 6-15). None met all the SISAQOL recommendations.

Interpretation

Low overall PROEAS score and delays in PRO data publication in GU cancer drug trials conducted in the past decade emphasize the need for improvement in quality of design and conduct of PRO endpoint in future trials and accelerated publication of PRO endpoints, using standardized analysis, and prespecified hypothesis driven endpoint. These improvements are essential for facilitating interpretation and application of PRO study findings to define patient care.

Funding

None.

Rosmarinic acid in combination with ginsenoside Rg1 suppresses colon cancer metastasis via co-inhition of COX-2 and PD1/PD-L1 signaling axis

Metastasis of colorectal cancer (CRC) is a leading cause of mortality among CRC patients. Elevated COX-2 and PD-L1 expression in colon cancer tissue has been linked to distant metastasis of tumor cells. Although COX-2 inhibitors and immune checkpoint inhibitors demonstrate improved anti-tumor efficacy, their toxicity and variable therapeutic effects in individual patients raise concerns. To address this challenge, it is vital to identify traditional Chinese medicine components that modulate COX-2 and PD-1/PD-L1: rosmarinic acid (RA) exerts striking inhibitory effect on COX-2, while ginsenoside Rg1 (GR) possesses the potential to suppress the binding of PD-1/PD-L1. In this study we investigated whether the combination of RA and GR could exert anti-metastatic effects against CRC. MC38 tumor xenograft mouse model with lung metastasis was established. The mice were administered RA (100 mg·kg-1·d-1, i.g.) alone or in combination with GR (100 mg·kg-1·d-1, i.p.). We showed that RA (50, 100, 150 μM) or a COX-2 inhibitor Celecoxib (1, 3, 9 μM) concentration-dependently inhibited the migration and invasion of MC38 cells in vitro. We further demonstrated that RA and Celecoxib inhibited the metastasis of MC38 tumors in vitro and in vivo via interfering with the COX-2-MYO10 signaling axis and inhibiting the generation of filopodia. In the MC38 tumor xenograft mice, RA administration significantly decreased the number of metastatic foci in the lungs detected by Micro CT scanning; RA in combination with GR that had inhibitory effect on the binding of PD-1 and PD-L1 further suppressed the lung metastasis of colon cancer. Compared to COX-2 inhibitors and immune checkpoint inhibitors, RA and GR displayed better safety profiles without disrupting the tissue structures of the liver, stomach and colon, offering insights into the lower toxic effects of clinical traditional Chinese medicine against tumors while retaining its efficacy.

Phase I LITESPARK-001 study of belzutifan for advanced solid tumors: Extended 41-month follow-up in the clear cell renal cell carcinoma cohort

BACKGROUND

Accumulation of the HIF-2α transcription factor is an oncogenic event implicated in the tumorigenesis of clear cell renal cell carcinoma (ccRCC). In the phase I LITESPARK-001 study, the first-in-class HIF-2α inhibitor belzutifan demonstrated antitumor activity and an acceptable safety profile for pretreated patients with advanced ccRCC. Updated data with additional follow-up of > 40 months are presented.

METHODS

LITESPARK-001 is an ongoing open-label study with a 3 + 3 dose-escalation design followed by an expansion phase. Patients with ccRCC enrolled at 7 sites received belzutifan 120 mg orally once daily until disease progression, unacceptable toxicity, or patient withdrawal. The data cutoff date was July 15, 2021. The primary end point was identifying the maximum tolerated dose and/or the recommended phase II dose. Secondary end points included objective response rate (ORR) and duration of response (DOR) per RECIST v1.1 by investigator assessment and safety.

RESULTS

Median follow-up was 41.2 months (range, 38.2-47.7). Patients received a median of 3 (range, 1-9) prior systemic therapies. Of 55 patients, 14 (25 %) achieved an objective response. Median DOR was not reached (range, 3.1 + to 38.0 + months). Adverse events (AEs) attributed to study treatment by investigator assessment were reported in 53 patients (96 %). 22 patients (40 %) had grade 3 treatment-related AEs; the most common were anemia (n = 13; 24 %) and hypoxia (n = 7; 13 %). No grade 4 or 5 treatment-related AEs occurred.

CONCLUSION

After a median follow-up of 41.2 months, belzutifan monotherapy demonstrated durable antitumor activity in patients with advanced ccRCC and acceptable safety.

CLINICALTRIALS

gov. NCT02974738.

Butyrate facilitates immune clearance of colorectal cancer cells by suppressing STAT1-mediated PD-L1 expression

OBJECTIVE

Immunotherapy has been proven to improve the prognosis of patients with advanced malignancy but has shown limited efficacy in patients with Colorectal Cancer (CRC). Increasing evidence suggests that butyrate, a bacterial metabolite, enhances the efficacy of cancer therapies by modulating immune responses. Here, the effect and the mechanism of butyrate on anti-PD-L1 therapy were investigated in CRC.

METHODS

The expression of PD-L1 and STAT1, and the lysine acetylation of STAT1 in CRC cells were observed after treatment with butyrate (2, 5, and 10 mM) for 24h or butyrate (5 mM) for 8, 16, and 24h. Site-directed mutations of STAT1 (K410R or K413R) were introduced to determine the role of STAT1 acetylation in modulating PD-L1 expression. The effect of butyrate on the cytotoxicity of CD8+ T-cells against CRC cells with or without PD-L1 overexpression was explored in vitro and in vivo.

RESULTS

Butyrate could suppress IFN-γ-induced PD-L1 up-regulation in CRC cells in a dose- and time-dependent way. Butyrate promoted the lysine acetylation of STAT1 to reduce STAT1 expression. Non-acetylated mutant STAT1 not only ameliorated butyrate-induced suppression of lysine acetylation and nuclear translocation of STAT1 but also blocked the effect of butyrate on PD-L1. Butyrate attenuated the IFN-γ-induced impairment of CD8+ T-cell cytotoxicity against CRC cells. Meanwhile, butyrate suppressed CRC tumor growth by enhancing CD8+ T-cell infiltration. However, directly overexpressing PD-L1 in CRC cells could abolish the effect of butyrate.

CONCLUSION

Butyrate strengthens the immune response to CRC cells by suppressing PD-L1 expression via acetylation of STAT1.

Patients with melanoma treated with immune checkpoint inhibitors who had non-thyroid endocrine and skin immune-related adverse events have better prognosis: A systematic review and meta-analysis

Background

Several studies have reported an association between the occurrence of immune-related adverse events (irAEs) and prognosis in patients with melanoma treated with immune checkpoint inhibitors (ICIs), but the results remain controversial. We conducted a systematic review and meta-analysis to investigate the association between irAEs and survival in patients with melanoma treated with ICIs.

Methods

We searched the PubMed, Web of Science, and China National Knowledge Infrastructure databases through May 5, 2022 for clinical studies evaluating the association between irAEs and in melanoma patients treated with ICIs. Combined hazard ratios (HRs) for overall survival (OS) and progression-free survival (PFS) were calculated using fixed- or random-effects models based on heterogeneity.

Results

A total of 60 articles were included, with 16,520 patients. In patients with melanoma treated with ICIs, the occurrence of irAEs was significantly associated with better OS (HR, 0.58; 95% confidence interval [CI], 0.51–0.66; P<0.00001) and PFS (HR, 0.61; 95%CI, 0.51–0.72; P<0.00001). Endocrine irAEs (OS, HR, 0.81; 95%CI, 0.72–0.92; P=0.001; PFS: HR, 0.84; 95%CI, 0.73–0.96, P=0.009), skin irAEs (OS, HR, 0.59; 95%CI, 0.41–0.85; P=0.004; PFS: HR, 0.43; 95%CI, 0.36–0.52; P<0.00001), vitiligo (OS, HR, 0.22; 95%CI, 0.15–0.31; P<0.00001; PFS, HR, 0.33; 95%CI, 0.25–0.44; P<0.00001), and grade 1–2 irAEs (OS, HR, 0.67; 95%CI, 0.58–0.78; P<0.00001; PFS, HR, 0.62; 95%CI, 0.51–0.76; P<0.00001) showed similar results. However, thyroid, lung, gastrointestinal, liver, and grade 3–4 irAEs were not significantly associated with OS and PFS. The occurrence of non-thyroid endocrine irAEs was significantly associated with better OS (HR, 0.22; 95%CI, 0.15–0.31; P<0.00001). In patients with melanoma treated with anti-programmed cell death protein 1 (OS, HR, 0.61; 95%CI, 0.51–0.72; P<0.00001; PFS, HR, 0.59; 95%CI, 0.47–0.74; P<0.00001), the association between irAEs and clinical benefit was clearer than in patients treated with anti-cytotoxic T-lymphocyte-associated protein 4 (OS, HR, 0.68; 95%CI, 0.52–0.89; P=0.005; PFS, HR, 0.93; 95%CI, 0.49–1.78; P=0.83).

Conclusion

Among patients with melanoma treated with ICIs, those who developed non-thyroid endocrine irAEs and cutaneous irAEs have better prognosis. This suggests that non-thyroid endocrine irAEs and cutaneous irAEs may be a prognostic biomarker for patients with melanoma treated with ICIs.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022338308.

Kinase activity profiling in renal cell carcinoma, benign renal tissue and in response to four different tyrosine kinase inhibitors

Kinase activity is frequently altered in renal cell carcinoma (RCC), and tyrosine kinase inhibitors (TKIs) are part of the standard treatment strategy in patients with metastatic disease. However, there are still no established biomarkers to predict clinical benefits of a specific TKI. Here, we performed protein tyrosine kinase (PTK) profiling using PamChip^® technology. The aim of this study was to identify differences in PTK activity between normal and malignant kidney tissue obtained from the same patient, and to investigate the inhibitory effects of TKIs frequently used in the clinics: sunitinib, pazopanib, cabozantinib and tivozanib. Briefly, our results showed that 36 kinase substrates differs (FDR < 0.05) between normal and cancer kidney tissue, where members of the Src family kinases and the phosphoinositide-3-kinase (PI3K) pathway exhibit high activity in renal cancer. Furthermore, ex vivo treatment of clear cell RCC with TKIs revealed that pathways such as Rap1, Ras and PI3K pathways were strongly inhibited, whereas the neurotrophin pathway had increased activity upon TKI addition. In our assay, tivozanib and cabozantinib exhibited greater inhibitory effects on PTK activity compared to sunitinib and pazopanib, implying they might be better suitable as TKIs for selected RCC patients.

Immune checkpoint inhibitor-based therapy for advanced clear cell renal cell carcinoma: A narrative review

The prognosis for advanced clear cell renal cell carcinoma (ccRCC) is not satisfactory, even though its treatment has evolved rapidly over the past 20 years. Systemic ccRCC treatment options mainly involve antiangiogenic therapy, immune checkpoint blockade, or a combination of these therapies, and as more clinical evidence becomes available, immune checkpoint inhibitors (ICIs) are increasingly dominant. Conventional ICIs lead to the restoration of T-cell activation and a reduction in T-cell depletion by specifically blocking programmed cell death 1 (PD-1), programmed cell death 1 ligand 1 (PD-L1) or cytotoxic T lymphocyte antigen 4 (CTLA-4), ultimately enhancing the antitumor immune response. There is no doubt that these therapies have achieved some clinical efficacy in the overall ccRCC population, but response rates and durability remain a great challenge. Therefore, novel immune checkpoints or new combination therapeutic strategies based on ICIs continue to be sought and developed. This review will provide a comprehensive overview of ICI-based therapeutic strategies in advanced ccRCC, including their mechanisms of action and the latest clinical evidence.

Exposure-Response Analysis to Support Nivolumab Once Every 4 Weeks Dosing in Combination with Cabozantinib in Renal Cell Carcinoma

PURPOSE

A benefit:risk assessment for a less-frequent nivolumab 480 mg Q4W + cabozantinib 40 mg QD dosing regimen was predicted using modeling and simulation of clinical trial data from nivolumab monotherapy studies and from the nivolumab 240 mg Q2W + cabozantinib 40mg QD dosing regimen, which demonstrated clinical benefit versus sunitinib in previously untreated advanced renal cell carcinoma (aRCC) in the phase III CheckMate 9ER trial (NCT03141177).

EXPERIMENTAL DESIGN

Multivariable Cox proportional-hazards analyses were conducted using nivolumab monotherapy data in previously treated aRCC and data from CheckMate 9ER to evaluate progression-free survival (PFS), overall survival (OS), and grade {greater than or equal to}2 immune-mediated adverse events (IMAEs).

RESULTS

Nivolumab 240 mg Q2W + cabozantinib versus nivolumab showed improvement in PFS (HR, 0.38; 95% CI, 0.31-0.47), OS (HR, 0.63 95% CI, 0.46-0.85), and increased risk of grade {greater than or equal to}2 IMAEs (HR, 2.19; 95% CI, 1.79-2.67). Nivolumab exposure was not a predictor of PFS/OS or grade {greater than or equal to}2 IMAEs. Lower nivolumab clearance, male sex, higher baseline bodyweight, and Karnofsky performance (100) were each associated with PFS/OS improvements. Region and IMDC poor score were negative OS predictors. Age, baseline albumin, and programmed death ligand-1 status were not significant PFS/OS predictors. Cabozantinib was a significant grade {greater than or equal to}2 IMAE predictor, driven by diarrhea and hepatic events. Model-predicted PFS/OS and grade {greater than or equal to}2 IMAE rates were similar (<2.5% difference) for nivolumab 240 mg Q2W + cabozantinib and 480 mg Q4W + cabozantinib.

CONCLUSIONS

Comparable benefit:risk was predicted for nivolumab 480 mg Q4W + cabozantinib and nivolumab 240 mg Q2W + cabozantinib.

Characterization of Molecular Heterogeneity Associated With Tumor Microenvironment in Clear Cell Renal Cell Carcinoma to Aid Immunotherapy

Clear cell renal cell carcinoma (ccRCC) is the most common type of kidney cancer and has strong immunogenicity. A systematically investigation of the tumor microenvironment (TME) in ccRCC could contribute to help clinicians develop personalized treatment and facilitate clinical decision-making. In this study, we analyzed the immune-related subtype of ccRCC on the basis of immune-related gene expression data in The Cancer Genome Atlas (TCGA, N = 512) and E-MTAB-1980 (N = 101) dataset, respectively. As a result, two subtypes (C1 and C2) were identified by performing non-negative matrix factorization clustering. Subtype C1 was characterized by increased advance ccRCC cases and immune-related pathways. A higher immune score, stromal score, TMB value, Tumor Immune Dysfunction and Exclusion (TIDE) prediction score, and immune checkpoint genes expression level were also observed in C1. In addition, the C1 subtype might benefit from chemotherapy and immunotherapy. The patients in subtype C2 had more metabolism-related pathways, higher tumor purity, and a better prognosis. Moreover, some small molecular compounds for the treatment of ccRCC were identified between the two subtypes by using the Connectivity Map (CMap) database. Finally, we constructed and validated an immune-related (IR) score to evaluate immune modification individually. A high IR score corresponded to a favorable prognosis compared to a low IR score, while more advanced tumor stage and grade cases were enriched in the low IR score group. The two IR score groups also showed a distinct divergence among immune status, TME, and chemotherapy. The external validation dataset (E-MTAB-1980) and another immunotherapy cohort (IMvigor 210) demonstrated that patients in the high IR score group had a significantly prolonged survival time and clinical benefits compared to the low IR score group. Together, characterization of molecular heterogeneity and IR signature may help develop new insights into the TME of ccRCC and provide new strategies for personalized treatment.

A Novel Ferroptosis-Related Pathway for Regulating Immune Checkpoints in Clear Cell Renal Cell Carcinoma

Ferroptosis is a novel form of cell death and plays a role in various diseases, especially tumors. It has been reported that ferroptosis is involved in the growth and progression of clear cell renal cell carcinoma (ccRCC); however, the specific molecular mechanisms are still unclear. In this study, we constructed a four-gene signature (FeSig) of ferroptosis-related genes via Cox regression analysis. ROC and survival analyses indicated that FeSig had good diagnostic and prognostic value. Further analysis revealed that ferroptosis was associated with tumor immunity in ccRCC. Next, weighted gene co-expression network analysis was performed to identify the potential regulatory mechanisms. Combined with correlation and survival analyses, the TAZ/WNT10B axis was identified as a tumor immune-related regulatory pathway. In conclusion, these findings suggest that ferroptosis is correlated with tumor immunity. The TAZ/WNT10B axis may be a novel biomarker and therapeutic target for immunotherapy in ccRCC.

Identification of the Prognosis Value and Potential Mechanism of Immune Checkpoints in Renal Clear Cell Carcinoma Microenvironment

Background

Kidney Renal Clear Cell Carcinoma (KIRC) is one of the most prevalent types of cancer worldwide. KIRC has a poor prognosis and, to date, immunotherapy based on immune checkpoints is the most promising treatment. However, the role of immune checkpoints in KIRC remains ambiguous.

Methods

Bioinformatics analyses and qRT-PCR were performed to explore and further confirm the prognostic value of immune checkpoint genes and their correlation with immune infiltration in KIRC samples.

Results

The expression of the immune checkpoint genes CD274, PDCD1LG2, HAVCR2, CTLA4, TIGFT, LAG3, and PDCD1 was upregulated in KIRC tissues. These genes were involved in the activation of the apoptosis pathway in KIRC. Low expression of CD274 and HAVCR2 and high expression of CTLA4 were associated with poor overall survival (OS), progression-free survival (PFS), and disease-free survival (DFS) of KIRC patients. The univariate and multivariate analyses revealed that CTLA4, HAVCR2, age, pTNM stage, and tumor grade were independent factors affecting the prognosis of KIRC patients. A predictive nomogram demonstrated that the calibration plots for the 3‐year and 5‐year OS probabilities showed good agreement compared to the actual OS of KIRC patients. The expression of CTLA4 and HAVCR2 were positively associated with immune cell infiltration, immune biomarkers, chemokines, and chemokine receptors. Moreover, miR-20b-5p was identified as a potential miRNA target of CTLA4 in KIRC.

Conclusion

Our study clarified the prognostic value of several immune checkpoint regulators in KIRC, revealing a CTLA4/miR-20b-5p axis in the control of immune cell infiltration in the tumor microenvironment.

Inhibition of hypoxia-inducible factor-2α in renal cell carcinoma with belzutifan: a phase 1 trial and biomarker analysis

Hypoxia-inducible factor-2α (HIF-2α) is a transcription factor that frequently accumulates in clear cell renal cell carcinoma (ccRCC), resulting in constitutive activation of genes involved in carcinogenesis. Belzutifan (MK-6482, previously known as PT2977) is a potent, selective small molecule inhibitor of HIF-2α. Maximum tolerated dose, safety, pharmacokinetics, pharmacodynamics and anti-tumor activity of belzutifan were evaluated in this first-in-human phase 1 study (NCT02974738). Patients had advanced solid tumors (dose-escalation cohort) or previously treated advanced ccRCC (dose-expansion cohort). Belzutifan was administered orally using a 3 + 3 dose-escalation design, followed by expansion at the recommended phase 2 dose (RP2D) in patients with ccRCC. In the dose-escalation cohort (n = 43), no dose-limiting toxicities occurred at doses up to 160 mg once daily, and the maximum tolerated dose was not reached; the RP2D was 120 mg once daily. Plasma erythropoietin reductions were observed at all doses; erythropoietin concentrations correlated with plasma concentrations of belzutifan. In patients with ccRCC who received 120 mg once daily (n = 55), the confirmed objective response rate was 25% (all partial responses), and the median progression-free survival was 14.5 months. The most common grade ≥3 adverse events were anemia (27%) and hypoxia (16%). Belzutifan was well tolerated and demonstrated preliminary anti-tumor activity in heavily pre-treated patients, suggesting that HIF-2α inhibition might offer an effective treatment for ccRCC.

Ocular side effects of checkpoint inhibitors

The incidence and impact of ocular side effects in patients treated with checkpoint inhibitors are not clearly defined. We reviewed prospective phase III clinical trials of checkpoint inhibitors applied in lung cancer, renal cell cancer, and melanoma. Case reports of the occurrence of ocular toxicities in patients receiving immune checkpoint inhibitors were also included. Of the 35 articles corresponding to phase III clinical trials with checkpoint inhibitors, ocular toxicity was described in four. Forty-six clinical cases of ocular toxicity after therapy with checkpoint inhibitors have been reported. The most frequently described ocular toxicities are uveitis, inflammatory orbital disease, and alterations of the ocular surface. Ocular toxicity is underestimated in checkpoint inhibitors clinical trials. Early ophthalmic examination and treatment with corticosteroids may improve the visual prognosis in these patients.

Immune Checkpoint Inhibitors in the Treatment of Renal Cancer: Current State and Future Perspective

Systemic treatment of renal cancer (RCC) has undergone remarkable changes over the past 20 years with the introduction of immunotherapeutic agents targeting programmed cell death (PD-1)/programmed death-ligand 1 (PD-L1) axis, as a single-agent or combined with anti-CTLA-4 monoclonal antibodies (MoAbs) or a multi-target vascular endothelial growth factor-(VEGF) tyrosine kinase inhibitor (TKI). In this paper, we review the main evidence on the use of Immune Checkpoint Inhibitors (ICIs) for RCC treatment from the first demonstration of activity of a nivolumab single agent in a phase I trial to the novel combination strategies (anti-PD-1 plus anti-CTLA4 or anti-PD-1 plus TKI). In addition, we discuss the use of anti-PD-1/PD-L1 agents in patients with non-clear cells and rare histological subtype RCC. Then, we critically examine the current findings in biomarkers that have been proposed to be prognostic or predictive to the response of immunotherapy including immune gene expression signature, B7-H1 expression, PBRM1 loss of function, PD-L1 expression, frame shift indel count, mutations in bromodomain-containing genes in patients with MiT family translocation RCC (tRCC), high expression of the T-effector gene signature, and a high myeloid inflammation gene expression pattern. To date, a single biomarker as a predictor of response has not been established. Since the dynamic behavior of the immune response and the different impact of ICI treatment on patients with specific RCC subtypes, the integration of multiple biomarkers and further validation in clinical trials are needed.