Checkpoint inhibitor immunotherapy in kidney cancer

Revealing NAPSA's role in ccRCC: Insights from single-cell RNA sequencing

BACKGROUND

Clear cell renal cell carcinoma (ccRCC) is aggressive and heterogeneous, resulting in poor prognosis due to frequent metastasis. Napsin A, an aspartic proteinase encoded by the NAPSA gene, is involved in protein processing and is expressed in the kidney and lung, but its function is not well understood. Studying ccRCC's molecular characteristics, including Napsin A, is vital for enhancing diagnostics and treatment.

METHODS

Single-cell RNA sequencing data from the GEO database (GSE210042) were analyzed, including seven tumor and two normal samples. The Seurat package was used for data preprocessing, clustering, and visualization. Differential expression and enrichment analyses were conducted between tumor and normal cells, and cell-to-cell communication was assessed between NAPSA + and NAPSA- cells. The correlation between NAPSA expression and EMT score was analyzed using TCGA-KIRC data. In vitro experiments involved transfecting OS-RC-2 and Caki-1 ccRCC cell lines with siRNA targeting NAPSA. Effect on the cellular EMT process induced by TGF-β1 was assessed by immunofluorescence staining.

RESULTS

NAPSA was primarily expressed in podocytes and ccRCC epithelial cells, with significantly reduced levels in tumor tissues associated with poor prognosis. NAPSA downregulation may influence various biological pathways and enhance communication with tumor-associated macrophages and mast cells. Silencing NAPSA increased TGF-β1-induced epithelial-mesenchymal transition (EMT).

CONCLUSION

The study highlights NAPSA's expression characteristics and potential role in ccRCC, suggesting it may serve as a biomarker. Further research is needed to elucidate NAPSA's mechanisms and explore its applications in precision medicine.

CircRNA GRAMD4 induces NBR1 expression to promote autophagy and immune escape in renal cell carcinoma

The tumor microenvironment (TME) in renal cell carcinoma (RCC) frequently exhibits significant immune cell infiltration. However, tumor cells often manage to evade immune surveillance. This study revealed the mechanism by which circular RNA circGRAMD4 regulates NBR1. CircGRAMD4 is markedly elevated in RCC, and its high levels are correlated with a poor prognosis. Notably, the absence of circGRAMD4 has been demonstrated to result in a significant inhibition of renal cancer cell growth. This inhibition has been attributed to an enhanced anti-tumor immunity mediated by CD8+ T cells. Mechanistically, circGRAMD4 interacts with the RBM4 protein, stabilizing the autophagic cargo receptor NBR1 mRNA. This interaction promotes NBR1 expression, which in turn leads to the degradation of MHC-I molecules through macroautophagy/autophagy pathways. Consequently, this process affects renal cancer cell antigen presentation, induces CD8+ T cell dysfunction, and contributes to tumor immune escape. Moreover, by inhibiting circGRAMD4 and using immune checkpoint blockers (ICB), the immunosuppressive TME is altered to prevent tumor immune evasion, ultimately increasing the effectiveness of ICB treatment. The discovery highlights the significant impact of circGRAMD4 on RCC immune escape and proposes that blocking circGRAMD4 could serve as a promising immunotherapy strategy when combined with ICB to enhance patient outcomes.

Immunotherapy Strategies After Immune Checkpoint Inhibitor Exposure in Renal Cell Carcinoma: A Review

Importance

Immune checkpoint inhibitors have transformed the treatment landscape for metastatic renal cell carcinoma; however, the failure of first-line therapeutic strategies remains a considerable challenge. Currently, clinicians face various issues, such as managing cases in patients who progress during treatment or relapse after adjuvant immunotherapy.

Observations

This review evaluates different strategies for treating patients with advanced kidney cancer previously exposed to immunotherapy. Evidence from other malignant neoplasms suggests potential effectiveness for rechallenging with immune checkpoint inhibitors. The most important available data are presented, including retrospective, prospective, and randomized clinical trials, to explore the role of immunotherapy in patients with renal cell carcinoma who have experienced prior failure of immune checkpoint inhibitors.

Conclusions and Relevance

Although retrospective data suggest modest effectiveness of an immunotherapy rechallenge treatment, larger phase 3 trials failed to demonstrate substantial benefit in progression-free survival and overall survival. Currently, no randomized evidence supports the use of agents targeting conventional immune checkpoints in patients with renal cell carcinoma who have previously received immunotherapy.

Loss of VHL-mediated pRb regulation promotes clear cell renal cell carcinoma

The von Hippel-Lindau (VHL) tumor suppressor is a substrate-defining component of E3 ubiquitin ligase complexes that target cellular substrates for proteasome-mediated degradation. VHL inactivation by mutation or transcriptional silencing is observed in most sporadic cases of clear cell renal cell carcinoma (ccRCC). VHL loss in ccRCC leads to constitutive stabilization of E3 ligase substrates, including hypoxia inducible factor α (HIFα). HIFα stabilization upon VHL loss is known to contribute to ccRCC development through transactivation of hypoxia-responsive genes. HIF-independent VHL targets have been implicated in oncogenesis, although those mechanisms are less well-defined than for HIFα. Using proximity labeling to identify proteasomal-sensitive VHL interactors, we identified retinoblastoma protein (pRb) as a novel substrate of VHL. Mechanistically, VHL interacts with pRb in a proteasomal-sensitive manner, promoting its ubiquitin-mediated degradation. Concordantly, VHL-inactivation results in pRb hyperstabilization. Functionally, loss of pRb in ccRCC led to increased cell death, transcriptional changes, and loss of oncogenic properties in vitro and in vivo. We also show that downstream transcriptional changes induced by pRb hyperstabilization may contribute to ccRCC tumor development. Together, our findings reveal a novel VHL-related pathway which can be therapeutically targeted to inhibit ccRCC tumor development.

Intratumoral mycobiome heterogeneity influences the tumor microenvironment and immunotherapy outcomes in renal cell carcinoma

The intratumoral mycobiome plays a crucial role in the tumor microenvironment, but its impact on renal cell carcinoma (RCC) remains unclear. We collected and quantitatively profiled the intratumoral mycobiome data from 1044 patients with RCC across four international cohorts, of which 466 patients received immunotherapy. Patients were stratified into mycobiota ecology-depauperate and mycobiota ecology-flourishing (MEF) groups based on fungal abundance. The MEF group had worse prognosis, higher fungal diversity, down-regulated lipid catabolism, and exhausted CD8+ T cells. We developed the intratumoral mycobiota signature and intratumoral mycobiota-related genes expression signature, which robustly predicted prognosis and immunotherapy outcomes in RCC and other cancers. Aspergillus tanneri was identified as a potential key fungal species influencing RCC prognosis. Our findings suggest that the intratumoral mycobiome suppresses lipid catabolism and induces T cell exhaustion in RCC.

Surgical Outcomes of Radical Nephrectomy and Inferior Vena Cava Thrombectomy Following Preoperative Systemic Immunotherapy: A Propensity Score Analysis

INTRODUCTION

The impact of neoadjuvant immune checkpoint inhibitors (ICIs) on perioperative outcomes of radical nephrectomy (RN) with inferior vena cava (IVC) thrombectomy for renal cell carcinoma (RCC) remains unclear. This study aimed to assess the safety of preoperative immunotherapy prior to surgical resection of RCC with IVC tumor thrombus.

PATIENTS AND METHODS

A retrospective review identified patients with RCC and IVC tumor thrombus who underwent concomitant nephrectomy and IVC thrombectomy. Patients were stratified based on preoperative ICI use. Inverse probability of treatment weighting (IPTW) was used to balance baseline characteristics. Intraoperative, postoperative, and oncological outcomes were evaluated using logistic, linear, and Cox proportional hazards regression models.

RESULTS

A total of 101 patients were included in the study: 39 (39%) received preoperative ICI and 62 (61%) underwent upfront surgery. After IPTW adjustment, propensity score variables were well-balanced. Preoperative ICI was associated with longer operative time (+99.7 minutes, 95% CI: 38-172, P = .001), but no significant differences in intraoperative incidents, postoperative complications, or postoperative renal function (all p > 0.05). With a median 19-month follow-up, exploratory analyses stratified by metastatic status revealed no significant differences in disease-free or overall survival between groups in both unweighted and IPTW-adjusted analyses (p > 0.05).

CONCLUSIONS

Preoperative immunotherapy appears safe and feasible for patients with RCC and IVC thrombus undergoing RN and thrombectomy, with no significant increase in postoperative morbidity despite longer operative times. Larger prospective studies with extended follow-up are needed to confirm these findings.

The clinical potential of PDL-1 pathway and some related micro-RNAs as promising diagnostic markers for breast cancer

BACKGROUND

Immune checkpoint pathways play important roles in breast cancer (BC) pathogenesis and therapy.

METHODS

Expression levels of programmed cell death protein 1 (PD-1), cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4), programmed death-ligand 1 (PD-L1), Forkhead box P3 (FOXP3), miR-155, and miR-195 were assessed in the peripheral blood of 90 BC patients compared to 30 healthy controls using quantitative real-time PCR (qRt-PCR). The plasma level of soluble MHC class I chain related-protein B (MIC-B) protein was assessed using the enzyme linked immunosorbent assay (ELISA) technique. The data were correlated to the clinico-pathological characteristics of the patients.

RESULTS

There was a significant increase in the expression levels of PDL-1 [17.59 (3.24-123), p < 0.001], CTLA-4 [23.34 (1.3-1267), p = 0.006], PD-1 [10.25 (1-280), p < 0.001], FOXP3 [11.5 (1-234.8), p = 0.001], miR-155 [87.3 (1.5-910), p < 0.001] in BC patients compared to normal controls. The miR-195 was significantly downregulated in BC patients [0.23 (0-0.98, p < 0.001]. The plasma level of MIC-B was significantly increased in the BC patients [0.941 (0.204-6.38) ng/ml], compared to the control group [0.351 (0.211-0.884) ng/mL, p < 0.00]. PDL-1, CTLA-4, PD-1, and FOXP3 achieved a specificity of 100% for distinguishing BC patients, at a sensitivity of 93.3%, 82.2%, 62.2%, and 71.1% respectively. The combined expression of PDL-1 and CTLA-4 scored a 100% sensitivity and 100% specificity for diagnosing BC (p < 0.001). The sensitivity, specificity, and AUC of miR-155 were 88.9%, 96.7%, and 0.934; respectively (p < 0.001). While those of miR-195 were 73.3%, 60%, and 0.716; respectively (p = 0.001). MIC-B expression showed a 77.8% sensitivity, 80% specificity, and 0.811 AUC at a cutoff of 1.17 ng/ml (p < 0.001). Combined expression of miR-155 and miR-195 achieved a sensitivity of 91.1%, a specificity of 96.7%, and AUC of 0.926 (p < 0.001). Multivariate analysis showed that PDL-1 (OR:13.825, p = 0.004), CTLA-4 (OR: 20.958, p = 0.010), PD-1(OR:10.550, p = 0.044), MIC-B (OR: 17.89, p = 0.003), miR-155 (OR: 211.356, P < 0.001), and miR-195(OR:0.006, P < 0.001) were considered as independent risk factors for BC.

CONCLUSIONS

The PB levels of PDL-1, CTLA-4, PD-1, FOXP3, MIC-B, miR-155, and miR-195 could be used as promising diagnostic markers for BC patients.

Clinical management of checkpoint inhibitor pneumonitis: Focus, challenges, and future directions

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment landscape for various malignancies by demonstrating exceptional antitumor effects and significant improvement in patient survival. Despite their overt therapeutic advantages, ICIs also induce immune-related adverse events (irAEs). Of these, checkpoint inhibitor pneumonitis (CIP) represents a prominent manifestation of pulmonary toxicity following ICI therapy, with incidence rates ranging from 2.7 % to 20.0 %. Notably, a substantial proportion of CIP cases show severe manifestations, often leading to life-threatening complications, which emphasizes its clinical significance. Understanding the risk factors and potential pathogenetic mechanisms of CIP, combined with vigilant monitoring during immunotherapy, is pivotal for early detection and management of this condition. Proactive strategies for the timely identification, accurate diagnosis, and effective management of CIP are essential to optimize patient outcomes. However, several challenges persist in CIP management, including management of severe and refractory cases, determining the timing of ICI rechallenge after CIP, management of long-term chronic CIP, and mitigating secondary infections. In order to manage this potentially life-threatening irAE effectively, it is urgent to establish multi-disciplinary treatment (MDT) management, precision CIP management, and practical surveillance systems for CIP monitoring, diagnosis, and management and to call for prospective multi-center clinical trials.

Analysis of risk factors for immune-related adverse events induced by immune checkpoint inhibitor treatment in cancer: A comprehensive systematic review

BACKGROUND

Immune-related adverse events (irAE) pose challenges to the use of immune checkpoint inhibitors (ICI). While risk factors for irAE are emerging, most studies are small, retrospective analyses that seldom report on diverse cancers or rare irAE. This paper reports a systematic review that summarises literature on irAE risk factors across cancers and proposes a categorisation approach.

METHOD

A systematic search was conducted in Medline OVID, Embase and Web of Science databases following PRISMA guidelines (CRD42022310127). Original research published in peer-reviewed journals between January 2017-Decmeber 2021 were selected. Eligible studies included patients with any cancer and evaluated any potential risk factor for any grade/type of irAE. Study design, sample size, and method for analysing association between irAE and risk factors were compared.

RESULTS

A total of 293 eligible studies containing 305,879 patients receiving ICI reported irAE in 58,291 patients (19.1 %). There were 221 retrospective, 55 prospective studies, and 17 systematic reviews/meta-analyses. Eighteen studies evaluated the predictive validity of models. Proposed risk factors were grouped based on common themes and underlying aetiology: 1) patient, 2) laboratory, 3) medical history, 4) cancer-related, 5) clinical score, 6) medications, and 7) imaging features. Opposing associations were reported between advancing age and irAE risk.

CONCLUSION

This systematic review provides a comprehensive overview of evidence on irAE risk factors across a large patient population. Studies were heterogeneous resulting from variations in design, sample size and analysis method, and lack generalisability due to statistically underpowered evidence. We propose an approach to categorise potential irAE risk factors to support ongoing collaborative research.

Integrated analyses of prognostic and immunotherapeutic significance of EZH2 in uveal melanoma

The EZH2 expression shows significantly associated with immunotherapeutic resistance in several tumors. A comprehensive analysis of the predictive values of EZH2 for immune checkpoint blockade (ICB) effectiveness in uveal melanoma (UM) remains unclear. We analyzed UM data from The Cancer Genome Atlas (TCGA) database, identified 888 differentially expressed genes (DEGs) associated with EZH2 expression, then conducted Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses to elucidate biological features of EZH2 in UM assays. The correlation of the expression of EZH2 with tumor immunity related factors such as immune-related pathways, infiltration of various immune cells, immune score and immune checkpoints were explored. The evaluation of EZH2's capability to predict immune therapy outcomes in UM was assessed by incorporating the Tumor Immune Dysfunction and Exclusion (TIDE) score. Lastly, programmed death-ligand 1 (PD-L1) expression was detected in an independent UM patient cohort by immunohistochemical analyses, the correlation of EZH2 with PD-L1 was evaluated. Results highlighted that the EZH2 expression was correlated with immune-related pathways, infiltration of various immune cells, immune score, the expression of immune checkpoints and immunotherapy sensitivity. Collectively, we suggested that EZH2 might be considered as predictor on the therapeutic effects of ICBs on UM patients, and a potential target for combined immunotherapy.

Progressive natural killer cell dysfunction in advanced-stage clear-cell renal cell carcinoma and association with clinical outcomes

BACKGROUND

Natural killer (NK) cells are important contributors to antitumor immunity in clear-cell renal cell carcinoma (ccRCC). However, their phenotype, function, and association with clinical outcomes in ccRCC remain poorly understood.

MATERIALS AND METHODS

We analyzed single-cell RNA sequencing data from 13 primary tumors, 1 localized tumor extension, and 1 metastasis from ccRCC patients at different clinical stages. For each primary tumor specimen, paired normal kidneys were also analyzed. Differential gene expression analysis was carried out to investigate NK cell phenotypes and to derive a gene expression signature. Gene signatures from NK cell subclusters of interest were used to interrogate bulk transcriptomic datasets and expression with clinical outcomes. Finally, tumor-infiltrating NK cell function (cytokine production and cytotoxicity) was assessed by isolation of live NK cells from ccRCC tissue, co-culture with K562 target cells, and measurement of cytokine production (interferon-γ) and cytotoxicity (CD107a) markers by flow cytometry.

RESULTS

Single-cell transcriptomic data were analyzed from 13 patients with ccRCC (tumor/normal kidney), resulting in 21 139 NK cells. Clustering analysis revealed six NK cell subsets. Bright-like NK cells were significantly enriched in advanced ccRCC compared with localized ccRCC and normal kidney, expressed markers of tissue residency (ZNF683/Hobit, ITGA1/CD49a, CD9, ITGAE/CD103), and had decreased expression of cytotoxicity genes (GZMB/Granzyme-B, PRF1/perforin). In independent cohorts (The Cancer Genome Atlas ccRCC cohort, CheckMate 025), a gene expression score representing this dysfunctional NK cell phenotype was enriched in advanced ccRCC and was associated with worse overall survival. Functional interrogation of tumor-infiltrating NK cells from ccRCC confirmed that tumor-resident CD49a+CD9+ NK cells had impaired cytotoxicity compared with CD49a-CD9- NK cells.

CONCLUSIONS

A dysfunctional, tumor-resident NK cell phenotype was enriched among patients with metastatic disease and associated with worse survival in patients with advanced ccRCC across multiple patient cohorts. Restoration of NK cell function (via cytokine stimulation or NK cell engineering) could provide a novel avenue for therapeutic intervention against ccRCC.

Chiral polypeptide hydrogels regulating local immune microenvironment and anti-tumor immune response

The impact of chirality on immune response has attracted great interest in cancer vaccine research recently. However, the study of chiral synthetic polypeptide hydrogels as cancer vaccines as well as of the impact of biomaterials themselves for antitumor immunotherapy has rarely been reported. Here, we show the key role of residue chirality of polypeptide hydrogels in antitumor immunity and local immune microenvironment regulation. Compared to poly(γ-ethyl-L-glutamate)-based hydrogels (L-Gel), poly(γ-ethyl-D-glutamate)-based hydrogels (D-Gel) induces enhanced level of immune cell infiltration. However, D-Gel causes higher levels of suppressive markers on antigen-presenting cells and even induces stronger T cell exhaustion than L-Gel. Finally, D-Gel establishes a local chronic inflammatory and immunosuppressive microenvironment and shows insufficient anti-tumor effects. Conversely, the milder host immune responses induced by L-Gel leads to more effective tumor inhibition. This study provides insights on the role of residue chirality in the regulation of local immune microenvironment and affecting antitumor immune response.

Allosteric inhibition of the tyrosine phosphatase SHP2 enhances the anti-tumor immunity of interferon α through induction of caspase-1-mediated pyroptosis in renal cancer

Interferon alpha (IFNα) leads to therapeutic effects on various tumors, especially renal cell cancer (RCC), by directly protecting against tumors cell proliferation or indirectly inducing an anti-tumor immune response. However, new combination therapies are needed to enhance the efficacy of IFNα and reduce its adverse effects during long-term treatment. In this study, we found that the anti-proliferative effects of IFNα on RCC cells in vitro and in vivo were greater after the allosteric inhibition of SHP2 by SHP099 than after treatment with enzymatic inhibitors of SHP2. SHP099 increased IFNα-induced pro-caspase-1 expression in RCC cells, activated the NLRP3 inflammasome, and induced pyroptosis. Mechanistically, SHP099 not only increased the expression of NLRP3 inflammasome components via the NF-κB signaling pathway, but also further activated the NLRP3 inflammasome by regulating mitochondrial homeostasis through ANT1-mediated reactive oxygen species modulation. Allosteric inhibition of SHP2 by SHP099 also potently enhanced the anti-tumor immunity induced by IFNα by modulating T cell proliferation and infiltration in vitro and in vivo. These results reveal the new function of SHP2 in NLRP3 inflammasome activation and pyroptosis in RCC and provide a basis for further investigating the combination of allosteric SHP2 inhibitors with IFNα in cancer immunotherapy.

Therapeutic vaccine targeting dual immune checkpoints induces potent multifunctional CD8+ T cell anti-tumor immunity

BACKGROUND

Vaccines targeting immune checkpoints represent a promising immunotherapeutic approach for solid tumors. However, the therapeutic efficacy of dual targeting immune checkpoints is still unclear in renal carcinoma.

METHODS

An adenovirus (Ad) vaccine targeting B7H1 and B7H3 was developed and evaluated for its therapeutic efficacy in subcutaneous, lung metastasis or orthotopic renal carcinoma mouse and humanized models using flow cytometry, Enzyme-linked immunosorbent spot (ELISPOT), cytotoxic T lymphocyte (CTL) killing, cell deletion, hematoxylin and eosin (HE) staining, and immunohistochemistry (IHC) assays.

RESULTS

The Ad-B7H1/B7H3 immunization effectively inhibited tumor growth and increased the induction and percentages of CD8+ T cells in subcutaneous tumor models. The vaccine enhanced the induction and maturation of CD11c+ or CD8+CD11c+ cells, promoting tumor-specific CD8+ T cell immune responses. This was evidenced by increased proliferation of CD8+ T cells and enhanced CTL killing activity. Deletion of CD8+ T cells in vivo abolished the anti-tumor effect of the Ad-B7H1/B7H3 vaccine, highlighting the pivotal role of functional CD8+ T cell immune responses. Moreover, significant therapeutic efficacy of the Ad-B7H1/B7H3 vaccine was observed in lung metastasis, orthotopic, and humanized tumor models through multifunctional CD8+ T cell immune responses.

CONCLUSIONS

The Ad vaccine targeting dual immune checkpoints B7H1 and B7H3 exerts a potent therapeutic effect for renal carcinoma and holds promise for solid tumor treatment.

Aristolochic acid-related renal cell carcinoma exhibits a distinct tumor-immune microenvironment favoring response to immune checkpoint blockade

Immune checkpoint blockade (ICB) is currently the standard of care for metastatic renal cell carcinoma (RCC), but treatment responses remain unpredictable. Aristolochic acid (AA), a prevalent supplement additive in Taiwan, has been associated with RCC and induces signature mutations, although its effect on the tumor-immune microenvironment (TIME) is unclear. We aimed to investigate the immune profile of AA-positive RCCs and explore its potential role as a susceptible candidate for ICB. Tissue samples from 22 patients with clear cell RCC (ccRCC) were collected for whole-exome sequencing to determine the genetic features and AA mutational signature (the discovery cohort). The corresponding RNA was sent for NanoString PanCancer IO 360 gene expression analysis to explore the immunological features. The formalin-fixed, parafilm-embedded slides of ccRCCs were sent for multiplex immunohistochemistry/immunofluorescence stain using Vectra system to evaluate the TIME. Tissues from two patients with metastatic RCC demonstrating complete response to ICB were sent for studies to validate the findings (the index patients). The results showed that AA mutational signatures with high tumor mutational burden (TMB) were present in 31.81% of the tumors in the discovery cohort. Three distinct clusters were observed through NanoString analysis. Clusters 1 and 3 were composed mainly of AA-positive RCCs. Cluster 3 RCCs exhibited higher tumor inflammation signature scores and higher immune cell type scores. Vectra analysis revealed a higher percentage of CD15+ and BATF3+ cells in cluster 1, whereas the percentage of CD8+ cells was potentially higher in cluster 3. Strong AA mutational signatures were found in the tumors of two index patients, and both were grouped to cluster 3. In conclusion, AA may induce higher TMB and alter the immune microenvironment in RCCs, which makes the tumors more susceptible to ICB. © 2024 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

The novel immune landscape of immune-checkpoint blockade in EBV-associated malignancies

The Epstein-Barr virus (EBV) is a ubiquitous gamma-herpesvirus and a class 1 carcinogen that is closely associated with a series of malignant lymphomas and epithelial cell carcinomas. Although these EBV-related cancers may exhibit different features in clinical symptoms and anatomical sites, they all have a characteristic immune-suppressed tumor immune microenvironment (TIME) that is tightly correlated with an abundance of tumor-infiltrating lymphocytes (TILs) that primarily result from the EBV infection. Overwhelming evidence indicates that an upregulation of immune-checkpoint molecules is a powerful strategy employed by the EBV to escape immune surveillance. While previous studies have mainly focused on the therapeutic effects of PD-1 and CTLA-4 blockades in treating EBV-associated tumors, several novel inhibitory receptors (e.g., CD47, LAG-3, TIM-3, VISTA, and DDR1) have recently been identified as potential targets for treating EBV-associated malignancies (EBVaMs). This review retrospectively summarizes the biological mechanisms used for immune checkpoint evasion in EBV-associated tumors. Its purpose is to update our current knowledge concerning the underlying mechanisms by which an immune checkpoint blockade triggers host antitumor immunity against EBVaMs. Additionally, this review may help investigators to more fully understand the correlation between EBV infection and tumor development and subsequently develop novel therapeutic strategies.

Upregulation of multiple key molecules is correlated with poor prognosis and immune infiltrates in hepatocellular carcinoma by bulk and single-cell RNA-seq

BACKGROUND

Recent discoveries in hepatocellular carcinoma (HCC) unveil key molecules. However, due to liver cancer's high heterogeneity, predicting patient prognosis is challenging. This study aims to construct a model for predicting HCC prognosis using multiple key genes.

METHODS

TCGA provided RNA expression and clinical data, differentially analyzed by DESeq2, edgeR, and Limma. The hub gene was pinpointed via CytoHubba's degree algorithm in Cytoscape. GO and KEGG analyses illuminated potential pathways. Single-cell sequencing detailed key gene expression in diverse cell types. The LASSO regression model predicted patient prognosis.

RESULT

In the RNA-seq analysis using three R packages, we identified 762 differentially expressed genes, with Cytoscape revealing ten key genes showing significant prognostic value (P < 0.05). GO and KEGG analyses highlighted key biological processes and pathways. IHC confirmed higher expression in cancer tissues. Reduced immune cell infiltration was observed in HCC tissues, and immune checkpoint analysis showed a strong correlation between PD1, CTLA4, and hub genes. Single-cell sequencing indicated higher expression of key genes in immune cells than hepatocytes. Cox analysis validated the riskScore as a reliable, independent prognostic marker (HR = 4.498, 95% CI: 2.526-8.007).

CONCLUSIONS

The results from differential analysis using three R packages are robust, revealing genes closely linked to immune cell infiltration in the tumor microenvironment. Additionally, a validated prognostic model for liver cancer was established based on key genes.

A new herbal extract carbon nanodot nanomedicine for anti-renal cell carcinoma through the PI3K/AKT signaling pathway

New Re carbon nanodots with narrow size distribution, good water solubility and high cell membrane permeability were prepared from a herbal extract. They exhibited high inhibitory effects on renal cancer A498 cells and renal cell carcinoma. They could stimulate the production of ROS, induce mitochondrial dysfunction, and accelerate the release of intracellular calcium ions in the A498 cells. Transcriptomic tests were performed on A498 cells after administration, and the results were analyzed by qPCR and immunofluorescence. The results suggested that the Re carbon nanodots could downregulate the abnormally activated PI3K/AKT signaling pathway and perform cell cycle arrest in the S phase along with the inhibition of cell proliferation. Finally, in conjunction with the abnormal mitochondrial function, the Re carbon nanodots could ultimately promote the apoptosis of the A498 cells. In vivo tumor-bearing mouse experiments further showed that the Re carbon nanodots had a strong inhibitory effect on xenograft kidney cancer tumors. The prepared Re carbon nanodots have good anti-renal cancer A498 cell and renal cell carcinoma bioactivity and are expected to be a potential drug for the treatment of kidney cancer with low toxicity and high safety.

EGCG inhibits migration, invasion and epithelial-mesenchymal transition of renal cell carcinoma by activating TFEB-mediated autophagy

BACKGROUND

The incidence of renal cell carcinoma (RCC) is already in the top ten of all types of cancers, with more than 4 %. Epigallocatechin gallate (EGCG), a polyphenolic compound extracted from green tea, has been shown to be effective in the treatment of various tumors. However, limited studies have demonstrated the effect of EGCG on RCC and its underlying molecular mechanisms.

METHODS

After exposure to gradient concentration (0,5,10,20,40,60,80,100 μM) of EGCG, the cell viability of RCC cells was determined by MTT assay. The migration and invasion abilities of RCC cells were investigated by wound healing and transwell assays. The expression levels of proteins involved in the epithelial-mesenchymal transition (EMT) and autophagy were explored by Western blotting assays. The formation of autophagosome was detected by electron microscope and LC3 puncta assays. Nude mouse xenograft model was used as the model system in vivo.

RESULTS

In the present study, EGCG significantly inhibited the migration, invasion and EMT of RCC cells in a concentrated manner. Further exploration of its mechanism indicated that autophagy is involved in EGCG-mediated metastasis inhibition and EMT inhibition of RCC cells. In addition, EGCG could significantly up-regulate the transcription factor EB (TFEB) and promotes its nuclear localization. The incorporation of TFEB into the nucleus enhanced the transcriptional levels of molecules associated with autophagy. TFEB knockdown inhibited EGCG-mediated autophagy activation, metastasis and EMT inhibition in RCC cells.

CONCLUSIONS

In conclusion, these findings demonstrate for the first time that EGCG inhibits migration, invasion, and EMT of RCC by activating TFEB-mediated autophagy. Therefore, the combination of EGCG and TFFB activators or EMT inhibitors is expected to be a promising therapeutic strategy for RCC.

Prognostic potential of standard laboratory parameters in patients with metastatic renal cell cancer receiving first-line immunotherapy

Through their involvement in cancer metabolism, alanine aminotransferase (ALAT), aspartate aminotransferase (ASAT), γ-glutamyltransferase (GGT) and lactate dehydrogenase (LDH) reflect the tumor burden and thus could have a prognostic potential for patients treated with immune checkpoint inhibitors (CPI). Therefore, this study investigated the prognostic potential of these parameters in a real-world cohort of patients with metastatic renal cell cancer (mRCC) under first-line CPI-based therapy. The retrospective study cohort included 82 mRCC patients treated with CPI-based first-line therapy between 2019 and 2023. Progression-free survival (PFS), overall survival (OS) and response rates were evaluated according to baseline levels and early dynamic changes of ALAT, ASAT, GGT and LDH. Multivariate Cox proportional hazard regression models were generated to identify independent prognosticators for PFS and OS. High baseline levels and non-normalized kinetics of ALAT, ASAT, GGT and LDH were significantly associated with shorter PFS and OS (p < 0.05), which was also reflected by lower response rates. Combining the four parameters at baseline into a 4-Risk-Score resulted in an enhanced prognostic power, as indicated by a higher C-index of 0.693 for OS compared to the individual parameters (≤ 0.663). Patients with all four risk factors present showed the worst PFS and OS. Overall, baseline levels and early kinetics of the four parameters as well as the 4-Risk-Score were identified as independent prognosticators for PFS and OS by multivariate analysis. As standard laboratory parameters, ALAT, ASAT, GGT and LDH are cost-effective and could be easily used either alone or in combination for therapy monitoring of CPI-treated mRCC patients.

KIR2DL2/DL3+NKs and Helios+Tregs in Peripheral Blood Predict Nivolumab Response in Patients with Metastatic Renal Cell Cancer

PURPOSE

To identify predictive factors of nivolumab sensitivity, peripheral blood NKs and regulatory T-cell (Treg) were evaluated in patients with metastatic renal cell carcinoma (mRCC) enrolled in the REVOLUTION trial.

EXPERIMENTAL DESIGN

Fifty-seven mRCCs being treated with nivolumab, as at least second-line of therapy, and 62 healthy donors were longitudinally evaluated (0-1-3-6-12 months) for peripheral NKs and Tregs, phenotype, and function. Multivariable logistic regression was conducted to identify the independent predictors. The 0.632+ internal cross-validation was used to avoid overfitting. The best cutoff value based on a 3-month clinical response was applied to progression-free survival (PFS) and overall survival (OS). Kaplan-Meier curves for PFS and OS were produced.

RESULTS

At pretreatment, mRCCs displayed high frequency of NKp46+NKs, NKp30+NKs, KIR2DL1+NKs, KIR2DL2/DL3+NKs, and PD1+NKs with reduced NK degranulation as well as high frequency of Tregs, PD1+Tregs, Helios+Tregs, and ENTPD1+Tregs. Responder patients, identified as a clinical response after 3 months of treatment, presented at pretreatment significantly low CD3+, high KIR2DL2/DL3+NKs, high PD1+Tregs, and high Helios+Tregs. Upon multivariate analysis, only KIR2DL2/DL3NKs and Helios+Tregs held as independent predictors of nivolumab responsiveness. The KIR2DL2/DL3+NKs >35.3% identified patients with longer OS, whereas the Helios+Tregs >34.3% displayed significantly longer PFS. After 1-month of nivolumab, responder patients showed low CD3+, high NKs, KIR2DL2/DL3+NKs, and ICOS+Tregs. Among these subpopulations, CD3+ and KIR2DL2/DL3+NKs held as independent predictors of nivolumab efficacy. Low CD3+ (≤71%) was significantly associated with longer PFS, whereas high KIR2DL2/DL3+NKs (>23.3%) were associated with both PFS and OS.

CONCLUSIONS

Pretreatment evaluation of Helios+Tregs/KIR2DL2/DL3+NKs and 1-month posttreatment CD3+/ KIR2DL2/DL3+NKs will predict nivolumab response in mRCCs.

DCS, a novel classifier system based on disulfidptosis reveals tumor microenvironment heterogeneity and guides frontline therapy for clear cell renal carcinoma

Background

Emerging evidence suggests that cell deaths are involved in tumorigenesis and progression, which may be treated as a novel direction of cancers. Recently, a novel type of programmed cell death, disulfidptosis, was discovered. However, the detailed biological and clinical impact of disulfidptosis and related regulators remains largely unknown.

Methods

In this work, we first enrolled pancancer datasets and performed multi-omics analysis, including gene expression, DNA methylation, copy number variation and single nucleic variation profiles. Then we deciphered the biological implication of disulfidptosis in clear cell renal cell carcinoma (ccRCC) by machine learning. Finally, a novel agent targeting at disulfidptosis in ccRCC was identified and verified.

Results

We found that disulfidptosis regulators were dysregulated among cancers, which could be explained by aberrant DNA methylation and genomic mutation events. Disulfidptosis scores were depressed among cancers and negatively correlated with epithelial mesenchymal transition. Disulfidptosis regulators could satisfactorily stratify risk subgroups in ccRCC, and a novel subtype, DCS3, owning with disulfidptosis depression, insensitivity to immune therapy and aberrant genome instability were identified and verified. Moreover, treating DCS3 with NU1025 could significantly inhibit ccRCC malignancy.

Conclusion

This work provided a better understanding of disulfidptosis in cancers and new insights into individual management based on disulfidptosis.

Identification and Validation of Cytotoxicity-Related Features to Predict Prognostic and Immunotherapy Response in Patients with Clear Cell Renal Cell Carcinoma

Background

Clear cell renal cell carcinoma (ccRCC) is a renal cortical malignancy with a complex pathogenesis. Identifying ideal biomarkers to establish more accurate promising prognostic models is crucial for the survival of kidney cancer patients.

Methods

Seurat R package was used for single-cell RNA-sequencing (scRNA-seq) data filtering, dimensionality reduction, clustering, and differentially expressed genes analysis. Gene coexpression network analysis (WGCNA) was performed to identify the cytotoxicity-related module. The independent cytotoxicity-related risk model was established by the survival R package, and Kaplan-Meier (KM) survival analysis and timeROC with area under the curve (AUC) were employed to confirm the prognosis and effectiveness of the risk model. The risk and prognosis in patients suffering from ccRCC were predicted by establishing a nomogram. A comparison of the level of immune infiltration in different risk groups and subtypes using the CIBERSORT, MCP-counter, and TIMER methods, as well as assessment of drug sensitivity to conventional chemotherapeutic agents in risk groups using the pRRophetic package, was made.

Results

Eleven ccRCC subpopulations were identified by single-cell sequencing data from the GSE224630 dataset. The identified cytotoxicity-related T-cell cluster and module genes defined three cytotoxicity-related molecular subtypes. Six key genes (SOWAHB, SLC16A12, IL20RB, SLC12A8, PLG, and HHLA2) affecting prognosis risk genes were selected for developing a risk model. A nomogram containing the RiskScore and stage revealed that the RiskScore contributed the most and exhibited excellent predicted performance for prognosis in the calibration plots and decision curve analysis (DCA). Notably, high-risk patients with ccRCC demonstrate a poorer prognosis with higher immune infiltration characteristics and TIDE scores, whereas low-risk patients are more likely to benefit from immunotherapy.

Conclusions

A ccRCC survival prognostic model was produced based on the cytotoxicity-related signature, which had important clinical significance and may provide guidance for ccRCC treatment.

Assessment of the Circulating PD-1 and PD-L1 Levels and P53 Expression as a Predictor of Relapse in Pediatric Patients with Wilms Tumor and Hypernephroma

Background/Objectives: Wilms tumor (WT) is the most common form of pediatric renal tumor, accounting for over 90% of cases followed by hypernephroma. Some pediatric patients with WT (10%) experience relapse or metastasis and have poor survival rates. PD-L1 assists cancer cells in escaping damage from the immune system. P53 mutations are found in relapsed WT tumor samples. We hypothesized that testing circulating PD-1 and PD-L1 and P53 expression levels could offer a simple method to predict patient relapse and explore novel treatments for pediatric WTs and hypernephroma. Methods: Flow cytometric detection of cPD-1, cPD-L1, and P53 expression in relapsed and in-remission WT and hypernephroma before and after one year of chemotherapy was performed. Results: Our data shows increased levels of cPD-L1 in relapsed pediatric patients with WT or hypernephroma before and after chemotherapy. There were also slight and significant increases in cPD-1 levels in relapsed groups before chemotherapy. Additionally, we observed significant decreases in P53 expression after one year of chemotherapy in relapsed pediatric patients. Conclusions: Our study found that circulating PD-L1 can be used as a predictor marker for WT and hypernephroma relapse. In conclusion, these circulating markers can assist in monitoring relapse in WT and hypernephroma patients without the need for several biopsies.

Tocilizumab and CytoSorb for delayed severe cytokine release syndrome after ipilimumab plus nivolumab immunotherapy

Cytokine release syndrome (CRS) is immune dysregulation phenomenon that is associated with immune checkpoint inhibitors. It is still difficult to distinguish CRS from other dangerous, acute and life-threatening medical disorders.We present a case of delayed grade 4 CRS following treatment of lung adenocarcinoma with ipilimumab plus nivolumab that warranted intensive care level treatment with abundant fluid resuscitation, two-tire vasopressor support, high-flow nasal oxygenation, corticosteroids in high dosages, as well as sustained low-efficiency daily diafiltration with CytoSorb hemadsorption and tocilizumab. Initial treatment of presumed septic shock of unknown origin did not yield results.After initiation of corticosteroids and particularly CytoSorb hemadsorption and tocilizumab, prompt clinical and laboratory improvement was observed.

Impact of baseline body composition on prognostic outcomes in urological malignancies treated with immunotherapy: a pooled analysis of 10 retrospective studies

OBJECTIVE

Numerous epidemiological investigations have explored the impact of body composition on the effectiveness of immune checkpoint inhibitors (ICIs) in urological malignancies (UM) patients, yielding conflicting findings. As a result, our study aims to elucidate the influence of baseline body composition on the long-term prognosis of UM patients treated with ICIs.

METHODS

We employed a rigorous systematic search across various databases, including PubMed, Embase, the Cochrane Library, and Google Scholar, to identify studies meeting our inclusion criteria. Our primary endpoints of interest encompassed overall survival (OS) and progression-free survival (PFS).

RESULTS

This analysis included a total of 10 articles with a combined patient cohort of 707 individuals. Our findings revealed a noteworthy association between several body composition parameters and unfavorable OS outcomes, including low psoas muscle index (PMI; HR: 3.88, p < 0.001), low skeletal muscle index (SMI; HR: 1.63, p < 0.001), sarcopenia (HR: 1.88, p < 0.001), low visceral adipose index (VAI; HR: 1.38, p = 0.018) and low subcutaneous adipose index (SAI; HR: 1.37, p = 0.018). Furthermore, our analysis demonstrated that low PMI (HR: 2.05, p = 0.006), low SMI (HR: 1.89, p = 0.002), sarcopenia (HR: 1.80, p < 0.001), and low VAI (HR:1.59, p = 0.005) were significantly correlated with inferior PFS. Conversely, SAI did not manifest a pronounced association with PFS in UM patients treated with ICIs.

CONCLUSION

Collectively, our study findings underscore a substantial relationship between baseline body composition and reduced clinical efficacy in UM patients undergoing ICI therapy.

AK7-deficiency reversal inhibits ccRCC progression and boosts anti-PD1 immunotherapy sensitivity

Clear cell renal cell carcinoma (ccRCC) is a common kidney cancer with subtle early symptoms, high recurrence rates, and low sensitivity to traditional treatments like radiotherapy and chemotherapy. Identifying novel therapeutic targets is critical. The expression level of adenylate kinases 7 (AK7) in ccRCC was examined by the TCGAportal and UALCAN databases. The effect of AK7 on proliferation, invasion and migration of ccRCC cell lines was evaluated by cell assay. The correlation between AK7 expression and prognosis, as well as its direct relationship with immunotherapy efficacy, was analyzed using CANCERTOOL and Kaplan-Meier plotter data. Moreover, the TISIDB database was used to study the relationship between AK7 and immune markers. The effect of overexpressed AK7 combined with PD1 monoclonal antibody on ccRCC was evaluated in animal experiments. The results showed that low level of AK7 expression was observed in ccRCC tissues. The expression of AK7 can regulate the proliferation, invasion, and migration of human ccRCC cell lines. The level of AK7 expression was associated with OS of ccRCC patients. This was potentially due to the negative connection between AK7 expression and CD8+ T cell depletion, indicating that immunotherapy might be less effective in individuals with low AK7 expression. Conversely, augmenting AK7 demonstrated an enhanced effectiveness of anti-PD1 therapy. The findings of our research strongly indicated that AK7 could serve as both a prognostic indicator and therapeutic target for patients with ccRCC. Moreover, the overexpression of AK7 combined with anti-PD1 held promising potential as a therapeutic approach for treating ccRCC.

Low Levels of Natural Killer Cell in Newly Diagnosed Myelodysplastic Syndromes Patients May Confer Poor Prognosis: A Retrospective Cohort Study

Background

Immune imbalance appears to have a critical role in tumor growth according to emerging research. Peripheral lymphocyte subsets are considered to reflect the systemic immune response and clinical prognosis. The prognostic value of lymphocyte subpopulations in myelodysplastic syndrome (MDS) patients remains unclear.

Methods

A total of 94 MDS patients were enrolled for the study. X-tile software was performed to determine the prognostic significance of various lymphocyte subpopulations, CD3, CD4, CD8, CD4/CD8 ratio, natural killer cell (NK) and CD19. Among them, the appropriate threshold of NK percent could be found only. Patients were divided into the high NK percent group and the low NK percent group. The prognostic significance was determined by univariate and multivariate Cox hazard models.

Results

MDS patients with lower NK level had significantly shorter overall survival (OS). Based on univariate analysis, male gender (P = 0.030), lower HB (<10 g/dl, P = 0.029), higher BM blast (>5%, P < 0.0001), higher-risk IPSS-R cytogenetic (P = 0.032) and lower NK percent (P < 0.0001) were significantly associated with shorter OS. Multivariate Cox proportional hazards regression analysis indicated that low NK was also independent adverse prognostic factor for OS in MDS.

Conclusion

Decreased NK level predicts poor prognosis independent of the IPSS-R and provide a novel evaluation factor for MDS patients.

Establishment and validation of a novel disulfidptosis-related immune checkpoint gene signature in clear cell renal cell carcinoma

BACKGROUND

Clear cell renal cell carcinoma (ccRCC) is the most prevalent subtype of renal tumors and is associated with a unfavorable prognosis. Disulfidptosis is a recently identified form of cell death mediated by disulfide bonds. Numerous studies have highlighted the significance of immune checkpoint genes (ICGs) in ccRCC. Nevertheless, the involvement of disulfidptosis-related immune checkpoint genes (DRICGs) in ccRCC remains poorly understood.

METHODS

The mRNA expression profiles and clinicopathological data of ccRCC patients were obtained from The Cancer Genome Atlas and Gene Expression Omnibus (GEO) databases. The associations between disulfidptosis-related genes (DRGs) and immune checkpoint genes (ICGs) were assessed to identify DRICGs. Cox regression analysis and least absolute shrinkage and selection operator (LASSO) analysis were conducted to construct a risk signature.

RESULTS

A total of 39 differentially expressed immune-related candidate genes were identified. A prognostic signature was constructed utilizing nine DRICGs (CD276, CD80, CD86, HLA-E, LAG3, PDCD1LG2, PVR, TIGIT, and TNFRSF4) and validated using GEO data. The risk model functioned as an independent prognostic indicator for ccRCC, while the associated nomogram provided a reliable scoring system for ccRCC. Gene set enrichment analysis indicated enrichment of phospholipase D, antigen processing and presentation, and ascorbate and aldarate metabolism-related signaling pathways in the high-risk group. Furthermore, the DRICGs exhibited correlations with the infiltration of various immune cells. It is noteworthy that patients with ccRCC categorized into distinct risk groups based on this model displayed varying sensitivities to potential therapeutic agents.

CONCLUSIONS

The novel DRICG-based risk signature is a reliable indicator for the prognosis of ccRCC patients. Moreover, it also aids in drug selection and correlates with the tumour immune microenvironment in ccRCC.

Identification of a signature of histone modifiers in kidney renal clear cell carcinoma

Kidney renal clear cell carcinoma (KIRC) is a cancer that is closely associated with epigenetic alterations, and histone modifiers (HMs) are closely related to epigenetic regulation. Therefore, this study aimed to comprehensively explore the function and prognostic value of HMs-based signature in KIRC. HMs were first obtained from top journal. Then, the mRNA expression profiles and clinical information in KIRC samples were downloaded from The Cancer Genome Atlas (TCGA) database and Gene Expression Omnibus (GEO) datasets. Cox regression analysis and least absolute shrinkage and selection operator (Lasso) analysis were implemented to find prognosis-related HMs and construct a risk model related to the prognosis in KIRC. Kaplan-Meier analysis was used to determine prognostic differences between high- and low-risk groups. Immune infiltration and drug sensitivity analysis were also performed between high- and low-risk groups. Eventually, 8 HMs were successfully identified for the construction of a risk model in KIRC. The results of the correlation analysis between risk signature and the prognosis showed HMs-based signature has good prognostic value in KIRC. Results of immune analysis of risk models showed there were significant differences in the level of immune cell infiltration and expression of immune checkpoints between high- and low-risk groups. The results of the drug sensitivity analysis showed that the high-risk group was more sensitive to several chemotherapeutic agents such as Sunitinib, Tipifarnib, Nilotinib and Bosutinib than the low-risk group. In conclusion, we successfully constructed HMs-based prognostic signature that can predict the prognosis of KIRC.

Development of prognostic signatures and risk index related to lipid metabolism in ccRCC

Background

Clear cell renal cell carcinoma (ccRCC) is a metabolic disorder characterized by abnormal lipid accumulation in the cytoplasm. Lipid metabolism-related genes may have important clinical significance for prognosis prediction and individualized treatment.

Methods

We collected bulk and single-cell transcriptomic data of ccRCC and normal samples to identify key lipid metabolism-related prognostic signatures. qPCR was used to confirm the expression of signatures in cancer cell lines. Based on the identified signatures, we developed a lipid metabolism risk score (LMRS) as a risk index. We explored the potential application value of prognostic signatures and LMRS in precise treatment from multiple perspectives.

Results

Through comprehensive analysis, we identified five lipid metabolism-related prognostic signatures (ACADM, ACAT1, ECHS1, HPGD, DGKZ). We developed a risk index LMRS, which was significantly associated with poor prognosis in patients. There was a significant correlation between LMRS and the infiltration levels of multiple immune cells. Patients with high LMRS may be more likely to respond to immunotherapy. The different LMRS groups were suitable for different anticancer drug treatment regimens.

Conclusion

Prognostic signatures and LMRS we developed may be applied to the risk assessment of ccRCC patients, which may have potential guiding significance in the diagnosis and precise treatment of ccRCC patients.

A new perspective: deciphering the aberrance and clinical implication of disulfidptosis signatures in clear cell renal cell carcinoma

Recent research has discovered disulfidptosis as a form of programmed cell death characterized by disulfide stress. However, its significance in clear cell renal cell carcinoma (ccRCC) remains unclear. To investigate this, data from The Cancer Genome Atlas were collected and used to identify ccRCC subgroups. Unsupervised clustering was employed to determine ccRCC heterogeneity. The mutation landscape and immune microenvironment of the subgroups were analyzed. The Disulfidptosis-Related Score was calculated using the LASSO-penalized Cox regression algorithm. The E-MATB-1980 cohort was used to validate the signature. The role of SLC7A11 in ccRCC metastasis was explored using western blotting and Transwell assays. Disulfidptosis-related genes are commonly downregulated in cancers and are linked to hypermethylation and copy number variation. The study revealed that ccRCC is divided into two sub-clusters: the disulfidptosis-desert sub-cluster, which is associated with a poor prognosis, a higher mutation frequency, and an immunosuppressive microenvironment. A 14-gene prognostic model was developed using differentially expressed genes and was validated in the E-MATB-1980 cohort. The low-risk group demonstrated longer overall and disease-free survival and responded better to targeted immunotherapy. Results from in vitro experiments identified SLC7A11 as a key participant in ccRCC metastasis.

Stemness related lncRNAs signature for the prognosis and tumor immune microenvironment of ccRCC patients

Long non-coding RNAs (lncRNAs) and cancer stem cells (CSCs) are crucial for the growth, migration, recurrence, and medication resistance of tumors. However, the impact of lncRNAs related to stemness on the outcome and tumor immune microenvironment (TIME) in clear cell renal cell carcinoma (ccRCC) is still unclear. In this study, we aimed to predict the outcome and TIME of ccRCC by constructing a stem related lncRNAs (SRlncRNAs) signature. We firstly downloaded ccRCC patients' clinical data and RNA sequencing data from UCSC and TCGA databases, and abtained the differentially expressed lncRNAs highly correlated with stem index in ccRCC through gene expression differential analysis and Pearson correlation analysis. Then, we selected suitable SRlncRNAs for constructing a prognostic signature of ccRCC patients by LASSO Cox regression. Further, we used nomogram and Kaplan Meier curves to evaluate the SRlncRNA signature for the prognose in ccRCC. At last, we used ssGSEA and GSVA to evaluate the correlation between the SRlncRNAs signature and TIME in ccRCC. Finally, We obtained a signtaure based on six SRlncRNAs, which are correlated with TIME and can effectively predict the ccRCC patients' prognosis. The SRlncRNAs signature may be a noval prognostic indicator in ccRCC.

The Evolving Landscape of Biomarkers for Immune Checkpoint Blockade in Genitourinary Cancers

In the past decade, immune checkpoint inhibitors (ICI) have been approved for treatment of genitourinary malignancies and have revolutionized the treatment landscape of these tumors. However, despite the remarkable success of these therapies in some GU malignancies, many patients' tumors do not respond to these therapies, and others may experience significant side effects, such as immune-related adverse events (iRAEs). Accordingly, biomarkers and improved prognostic tools are critically needed to help predict which patients will respond to ICI, predict and mitigate risk of developing immune-related adverse events, and inform personalized choice of therapy for each patient. Ongoing clinical and preclinical studies continue to provide an increasingly robust understanding of the mechanisms of the response to immunotherapy, which continue to inform biomarker development and validation. Herein, we provide a comprehensive review of biomarkers of the response to immunotherapy in GU tumors and their role in selection of therapy and disease monitoring.

Multi-omics analysis of macrophage-associated receptor and ligand reveals a strong prognostic signature and subtypes in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a significant contributor to morbidity and mortality worldwide. The interaction between receptors and ligands is the primary mode of intercellular signaling and plays a vital role in the progression of HCC. This study aimed to identify the macrophage-related receptor ligand marker genes associated with HCC and further explored the molecular immune mechanisms attributed to altered biomarkers. Single-cell RNA sequencing data containing primary and recurrent samples were downloaded from the China National GeneBank. Cell types were first identified to explore differences between immune cells from different sample sources. CellChat analysis was used to infer and analyze intercellular communication networks quantitatively. Three molecular subtypes were constructed based on the screened twenty macrophage-associated receptor ligand genes. Bulk RNA-Seq data were downloaded from The Cancer Genome Atlas and Gene Expression Omnibus databases. After the screening, the minor absolute shrinkage and selection operator (LASSO) regression model was employed to identify key markers. After collecting peripheral blood and clinical information from patients, an enzyme-linked immunosorbent assay (ELISA) was used to detect the correlation between key markers and IL-10, one of the macrophage markers. After developing a new HCC risk adjustment model and conducting analysis, it was found that there were significant differences in immune status and gene mutations between the high-risk and low-risk groups of patients based on macrophage-associated receptor and ligand genes. This study identified SPP1, ANGPT2, and NCL as key biological targets for HCC. The drug-gene interaction network analysis identified wortmannin, ribavirin, and tarnafloxin as potential therapeutic drugs for the three key markers. In a clinical cohort study, patients with immune checkpoint inhibitor (ICI) resistance had significantly higher expression levels of OPN, ANGPT2, NCL, and IL-10 than patients with ICI-responsiveness. These three key markers were positively correlated with the expression level of IL-10. The signature based on macrophage-associated receptor and ligand genes can accurately predict the prognosis of patients with HCC and the sensitivity to immunotherapy. These results may help guide the development of targeted prevention and personalized treatment of HCC.

IGSF8 is an innate immune checkpoint and cancer immunotherapy target

Antigen presentation defects in tumors are prevalent mechanisms of adaptive immune evasion and resistance to cancer immunotherapy, whereas how tumors evade innate immunity is less clear. Using CRISPR screens, we discovered that IGSF8 expressed on tumors suppresses NK cell function by interacting with human KIR3DL2 and mouse Klra9 receptors on NK cells. IGSF8 is normally expressed in neuronal tissues and is not required for cell survival in vitro or in vivo. It is overexpressed and associated with low antigen presentation, low immune infiltration, and worse clinical outcomes in many tumors. An antibody that blocks IGSF8-NK receptor interaction enhances NK cell killing of malignant cells in vitro and upregulates antigen presentation, NK cell-mediated cytotoxicity, and T cell signaling in vivo. In syngeneic tumor models, anti-IGSF8 alone, or in combination with anti-PD1, inhibits tumor growth. Our results indicate that IGSF8 is an innate immune checkpoint that could be exploited as a therapeutic target.

Early kinetics of C-reactive protein as prognosticator for survival in a real-world cohort of patients with metastatic renal cell cancer under first-line therapy with immune checkpoint inhibitors

PURPOSE

This study investigated the prognostic potential of baseline C-reactive protein (CRP) levels and early CRP kinetics in a real-world cohort of patients with metastatic renal cell carcinoma (mRCC) under first-line (1L) therapy with immune checkpoint inhibitors (CPI).

METHODS/PATIENTS

Analyses were performed retrospectively in a cohort of 61 mRCC patients under CPI-based 1L therapy. Patients were stratified based on baseline CRP (< 10 vs ≥ 10 mg/l) and CRP change within the initial three months of CPI therapy (normal: baseline < 10 mg/l, normalized: baseline ≥ 10 mg/l and nadir < 10 mg/l, non-normalized: baseline and nadir ≥ 10 mg/l). Finally, the association of baseline CRP and CRP change with progression-free (PFS) and overall survival (OS) was evaluated.

RESULTS

Baseline CRP was not significantly associated with both PFS (p = 0.666) and OS (p = 0.143). Following stratification according to early CRP kinetics, 23, 25 and 13 patients exhibited normal, normalized and non-normalized CRP levels, respectively. Patients with normal and normalized CRP had a markedly prolonged PFS (p = 0.091) and OS (p = 0.008) compared to patients with non-normalized CRP. Consequently, significantly better PFS (p = 0.031) and OS (p = 0.002) were observed for the combined normal-normalized group. In multivariate analysis including ECOG and IMDC risk, normalized CRP kinetics alone or in combination with the normal group was identified as significant independent risk factor for OS, whereas a statistical trend was observed for PFS.

CONCLUSIONS

The present study emphasizes the prognostic potential of early CRP kinetics in CPI-treated mRCC. As a standard laboratory parameter, CRP can be easily implemented into clinical routine to facilitate therapy monitoring.

Development of small-molecular-based radiotracers for PET imaging of PD-L1 expression and guiding the PD-L1 therapeutics

PURPOSE

Programmed cell death protein ligand 1 (PD-L1) is a crucial biomarker for immunotherapy. However, nearly 70% of patients do not respond to PD-L1 immune checkpoint therapy. Accurate monitoring of PD-L1 expression and quantification of target binding during treatment are essential. In this study, a series of small-molecule radiotracers were developed to assess PD-L1 expression and direct immunotherapy.

METHODS

Radiotracers of [68Ga]Ga-D-PMED, [68Ga]Ga-D-PEG-PMED, and [68Ga]Ga-D-pep-PMED were designed based on a 2-methyl-3-biphenyl methanol scaffold and successfully synthesized. Cellular experiments and molecular docking assays were performed to determine their specificity for PD-L1. PD-L1 status was investigated via positron emission tomography (PET) imaging in MC38 tumor models. PET imaging of [68Ga]Ga-D-pep-PMED was performed to noninvasively quantify PD-L1 blocking using an anti-mouse PD-L1 antibody (PD-L1 mAb).

RESULTS

The radiosyntheses of [68Ga]Ga-D-PMED, [68Ga]Ga-D-PEG-PMED, and [68Ga]Ga-D-pep-PMED were achieved with radiochemical yields of 87 ± 6%, 82 ± 4%, and 79 ± 9%, respectively. In vitro competition assays demonstrated their high affinities (the IC50 values of [68Ga]Ga-D-PMED, [68Ga]Ga-D-PEG-PMED, and [68Ga]Ga-D-pep-PMED were 90.66 ± 1.24, 160.8 ± 1.35, and 51.6 ± 1.32 nM, respectively). At 120 min postinjection (p.i.) of the radiotracers, MC38 tumors displayed optimized tumor-to-muscle ratios for all radioligands. Owing to its hydrophilic modification, [68Ga]Ga-D-pep-PMED had the highest target-to-nontarget (T/NT) ratio of approximately 6.2 ± 1.2. Interestingly, the tumor/liver ratio was hardly affected by different concentrations of the inhibitor BMS202. We then evaluated the impacts of dose and time on accessible PD-L1 levels in the tumor during anti-mouse PD-L1 antibody treatment. The tumor uptake of [68Ga]Ga-D-pep-PMED significantly decreased with increasing PD-L1 mAb dose. Moreover, after 8 days of treatment with a single antibody, the uptake of [68Ga]Ga-D-pep-PMED in the tumor significantly increased but remained lower than that in the saline group.

CONCLUSION

PET imaging with [68Ga]Ga-D-pep-PMED, a small-molecule radiotracer, is a promising tool for evaluating PD-L1 expression and quantifying the target blockade of PD-L1 to assist in the development of effective therapeutic regimens.

Molecular insight into T cell exhaustion in hepatocellular carcinoma

Hepatocellular carcinoma is one of the leading causes of cancer-related mortality globally. The emergence of immunotherapy has been shown to be a promising therapeutic approach for hepatocellular carcinoma in recent years. It has been well known that T cell plays a key role in current immunotherapy. However, sustained exposure to antigenic stimulation within the tumor microenvironment may lead to T cell exhaustion, which may cause treatment ineffectiveness. Therefore, reversing T cell exhaustion has been an important issue for the clinical application of immunotherapy, and a comprehensive understanding of the intricacies surrounding T cell exhaustion and its underlying mechanisms is imperative for devising strategies to overcome the T cell exhaustion during treatment. In this review, we summarized the reported drivers of T cell exhaustion in hepatocellular carcinoma and delineate potential ways to reverse it. Additionally, we discussed the interplay among metabolic plasticity, epigenetic regulation, and transcriptional factors in exhausted T cells in hepatocellular carcinoma, and their implication for future clinical applications.

Rationale for immune checkpoint inhibitors plus targeted therapy for advanced renal cell carcinoma

Renal cell carcinoma (RCC) is a frequent urological malignancy characterized by a high rate of metastasis and lethality. The treatment strategy for advanced RCC has moved through multiple iterations over the past three decades. Initially, cytokine treatment was the only systemic treatment option for patients with RCC. With the development of medicine, antiangiogenic agents targeting vascular endothelial growth factor and mammalian target of rapamycin and immunotherapy, immune checkpoint inhibitors (ICIs) have emerged and received several achievements in the therapeutics of advanced RCC. However, ICIs have still not brought completely satisfactory results due to drug resistance and undesirable side effects. For the past years, the interests form researchers have been attracted by the combination of ICIs and targeted therapy for advanced RCC and the angiogenesis and immunogenic tumor microenvironmental variations in RCC. Therefore, we emphasize the potential principle and the clinical progress of ICIs combined with targeted treatment of advanced RCC, and summarize the future direction.

TRIB3 promotes the progression of renal cell carcinoma by upregulating the lipid droplet-associated protein PLIN2

Abnormal lipid metabolism and lipid accumulation are characteristic hallmarks of renal cell carcinoma (RCC). While there is prior evidence closely linking such lipid accumulation within RCC cells and consequent tumorigenesis, the mechanisms underlying this process remain incompletely understood. In this study, a series of bioinformatics analyses were initially performed by screening RCC databases and gene sets, ultimately leading to the identification of TRIB3 as an oncogene that functions as a central regulator of lipid metabolism. TRIB3 overexpression was observed in both RCC patient tumor tissues and cell lines, and this upregulation was correlated with a worse RCC patient prognosis. When TRIB3 was knocked down, this resulted in a reduction in lipid accumulation and the consequent induction of endoplasmic reticulum (ER) stress-related apoptotic cell death. At the molecular level, interactions between TRIB3 and PLIN2 were found to abrogate TEB4-mediated PLIN2 ubiquitination and consequent degradation, thus maintaining higher PLIN2 expression levels. This simultaneously helps facilitate the accumulation of lipids while preserving ER homeostasis, thus driving accelerated RCC tumor progression. This TRIB3-PLIN2 axis thus represents a promising new target for efforts to treat RCC.

Established and emerging biomarkers of immunotherapy in renal cell carcinoma

Immunotherapies, such as immune checkpoint inhibitors, have heralded impressive progress for patient care in renal cell carcinoma (RCC). Despite this success, some patients' disease fails to respond, and other patients experience significant side effects. Thus, development of biomarkers is needed to ensure that patients can be selected to maximize benefit from immunotherapies. Improving clinicians' ability to predict which patients will respond to immunotherapy and which are most at risk of adverse events - namely through clinical biomarkers - is indispensable for patient safety and therapeutic efficacy. Accordingly, an evolving suite of therapeutic biomarkers continues to be investigated. This review discusses biomarkers for immunotherapy in RCC, highlighting current practices and emerging innovations, aiming to contribute to improved outcomes for patients with RCC.

Successful Outcome of a Patient with Concomitant Pancreatic and Renal Carcinoma Receiving Secoisolariciresinol Diglucoside Therapy Alone: A Case Report

Introduction

Pancreatic cancer (PC) is among the deadliest malignancies. Kidney cancer (KC) is a common malignancy globally. Chemo- or radio-therapies are not very effective to control PC or KC, and overdoses often cause severe site reactions to the patients. As a result, novel treatment strategies with high efficacy but without toxic side effects are urgently desired. Secoisolariciresinol diglucoside (SDG) belongs to plant lignans with potential anticancer activities, but clinical evidence is not available in PC or KC treatment.

Patient Concerns

We report a rare case of an 83-year-old female patient with pancreatic and kidney occupying lesions that lacked the conditions to receive surgery or chemo- or radiotherapy.

Diagnosis

Pancreatic and kidney cancers.

Interventions

We gave dietary SDG to the patient as the only therapeutics.

Outcomes

SDG effectively halted progression of both PC and KC. All clinical manifestations, including bad insomnia, loss of appetite, stomach symptoms, and skin itching over the whole body, all disappeared. The initial massive macroscopic hematuria became microscopic and infrequent, and other laboratory results also gradually returned to normal. Most of the cancer biomarkers, initially high such as CEA, CA199, CA724, CA125, came down rapidly, among which CA199 changed most radically. This patient has had progression-free survival of one year so far.

Conclusion

These results demonstrate the potent inhibitory effects of SDG on PC and KC of this patient and provide promising novel therapeutics for refractory malignant tumors.

Development and verification of a novel immunogenic cell death-related signature for predicting the prognosis and immune infiltration in triple-negative breast cancer

BACKGROUND

Insufficient understanding of the pathogenesis and tumor immunology of triple-negative breast cancer (TNBC) has limited the development of immunotherapy. The importance of tumor microenvironment (TME) in immunotyping, prognostic assessment and immunotherapy efficacy of cancer has been emphasized, however, potential immunogenic cell death (ICD) related genes function in TME of TNBC has been rarely investigated.

AIMS

To initially explore the role and related mechanisms of ICD in TNBC, especially the role played in the TME of TNBC, and to identify different relevant subtypes based on ICD, and then develop an ICD-related risk score to predict each TNBC patient TME status, prognosis and immunotherapy response.

METHODS AND RESULTS

In this study, we identified distinct ICD-related modification patterns based on 158 TNBC cases in the TCGA-TNBC cohort. We then investigated the possible correlation between ICD-related modification patterns and TME cell infiltration characteristics in TNBC. By using univariate Cox and least absolute shrinkage and selection operator (LASSO) regression analysis, we created a risk scoring system (ICD score) to quantifiably evaluate the impact of ICD-related modification patterns in individual TNBC patient. Two different ICD-related modification patterns were found with significant differences in immune infiltration. Lower ICD score was correlated with higher immune infiltration, tumor mutational burden and significantly enriched in immune-related pathways, indicating a strong ability to activate immune response, which might account for relatively favorable prognosis of TNBC patients and could serve as a predictor to select suitable candidates for immunotherapy. We used two independent cohorts, GSE58812 cohort and Metabric cohort to validate prognosis and immunohistochemistry for preliminary in vitro validation.

CONCLUSION

This study evidenced that the ICD-related modification patterns might exert pivotal roles in the immune infiltration landscape of TNBC and ICD score might act as potential predictors of prognostic assessment and immunotherapy response. This research provides unique insights for individualize immune treatment strategies and promising immunotherapy candidates screening.

LGALS3BP is a novel and potential biomarker in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is the most common solid renal tumor. Therefore, it is necessary to explore the related tumor markers. LGALS3BP (galectin 3 binding protein) is a multifunctional glycoprotein implicated in immunity and cancer. Some studies have shown that LGALS3BP promotes the occurrence and development of tumors. However, their exact role in renal tumorigenesis remains unclear. Our study used a webserver to explore the mRNA expression and clinical features of LGALS3BP in ccRCC. Survival analysis showed that patients with high LGALS3BP expression had significantly worse OS and DFS than those with low LGALS3BP expression. LGALS3BP expression is significantly related to B cells, CD4+ T cells, macrophages, neutrophils, and dendritic cells. Furthermore, we determined that LGALS3BP is significantly associated with angiogenesis, stemness and proliferation in renal cancer. Three phenotypes may be associated with a poor prognosis. Genes related to proliferation, angiogenesis and stemness were derived from a Venn diagram of FGF2. FGF2 is negatively correlated with proliferation and positively correlated with angiogenesis. Finally, we screened for drugs that may have potential therapeutic value for ccRCC. The PCR results showed that the expression of LGALS3BP in the normal cell line was lower than that in the tumor cell lines. After LGALS3BP knockdown, the proliferation of 769-P and 786-O cells decreased. The present findings show that LGALS3BP is critical for ccRCC cell proliferation and may be a potential target and biomarker for ccRCC.

Integration of basement membrane-related genes in a risk signature for prognosis in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is characterized by high heterogeneity and recurrence rates, posing significant challenges for stratification and treatment. Basement membrane-related genes (BMGs) play a crucial role in tumor initiation and progression. Clinical and transcriptomic data of ccRCC patients were extracted from TCGA and GEO databases. We employed univariate regression and LASSO-Cox stepwise regression analysis to construct a BMscore model based on BMGs expression level. A nomogram combining clinical features and BMscore was constructed to predict individual survival probabilities. Further enrichment analysis and immune-related analysis were conducted to explore the enriched pathways and immune features associated with BMGs. High-risk individuals predicted by BMscore exhibited poorer overall survival, which was consistent with the validation dataset. BMscore was identified as an independent risk factor for ccRCC. Functional analysis revealed that BMGs were related to cell-matrix and tumor-associated signaling pathways. Immune profiling suggests that BMGs play a key role in immune interactions and the tumor microenvironment. BMGs serve as a novel prognostic predictor for ccRCC and play a role in the immune microenvironment and treatment response. Targeting the BM may represent an alternative therapeutic approach for ccRCC.

Single-cell analysis reveals ADGRL4+ renal tubule cells as a highly aggressive cell type in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is a highly heterogeneous cancer that poses great challenge to clinical treatment and prognostic prediction. Characterizing the cellular landscape of ccRCC in a single-cell dimension can help better understand the tumor heterogeneity and molecular mechanisms of ccRCC. This study analyzed single-cell profiles in ccRCC samples and para-tumor samples from Gene Expression Omnibus and identified a highly heterogeneous subcluster of renal tubule cells. Single-cell regulatory network inference and clustering analyses and cell communication analysis were performed to develop transcription factor-target gene regulatory networks and cell-cell interactions. Additionally, the distribution and prognostic risk of renal tubule cells from spatial transcriptome data (GSM6415706) and The Cancer Genome Atlas-Kidney Clear Cell Carcinoma data were analyzed. A total of 10 cell types were identified in ccRCC and para-tumor samples. The ccRCC renal tubule cells showed a high expression of the oncogene nicotinamide N-methyltransferase and a significantly high degree of tumor heterogeneity. We further identified 6 cell subclusters with specific expression of BEX2, PTHLH, SFRP2, KLRB1, ADGRL4, and HGF from the ccRCC renal tubule cells. ADGRL4+ renal tubule cells had highly metastatic and angiogenesis-inducing characteristics, with more ADGRL4+ renal tubule cells indicating a worse survival. ADGRL4+ renal tubule cells regulated the metastasis of other renal tubule cells through metastasis-related receptor-ligand communication. We also found that ADGRL4+ renal tubule cells clustered around the glomeruli but the rest of the renal tubule cell subclusters rarely localized in ccRCC tissues. ETS1 and ELK3 -dominant GRNs were remarkably activated in ADGRL4+ renal tubule cells, functionally, knockdown of ELK3 in A498 significantly disturbedaffected the cell migration and invasion. ADGRL4+ renal tubule cells, which were highly metastatic and invasive, might be an essential cell subcluster for ccRCC, and ADGRL4 could be used a novel therapeutic target.

Targeting Protein Tyrosine Phosphatases to Improve Cancer Immunotherapies

Advances in immunotherapy have brought significant therapeutic benefits to many cancer patients. Nonetheless, many cancer types are refractory to current immunotherapeutic approaches, meaning that further targets are required to increase the number of patients who benefit from these technologies. Protein tyrosine phosphatases (PTPs) have long been recognised to play a vital role in the regulation of cancer cell biology and the immune response. In this review, we summarize the evidence for both the pro-tumorigenic and tumour-suppressor function of non-receptor PTPs in cancer cells and discuss recent data showing that several of these enzymes act as intracellular immune checkpoints that suppress effective tumour immunity. We highlight new data showing that the deletion of inhibitory PTPs is a rational approach to improve the outcomes of adoptive T cell-based cancer immunotherapies and describe recent progress in the development of PTP inhibitors as anti-cancer drugs.

Immunotherapy in hepatocellular carcinoma: an overview of immune checkpoint inhibitors, drug resistance, and adverse effects

Hepatocellular carcinoma (HCC) is a concerning liver cancer with rising incidence and mortality rates worldwide. The effectiveness of traditional therapies in managing advanced HCC is limited, necessitating the development of new therapeutic strategies. Immune checkpoint inhibitors (ICIs) have emerged as a promising strategy for HCC management. By preventing tumor cells from evading immune surveillance through immunological checkpoints, ICIs can restore the immune system’s ability to target and eliminate tumors. While ICIs show promise in enhancing the immune response against malignancies, challenges such as drug resistance and adverse reactions hinder their efficacy. To address these challenges, developing individualized ICI treatment strategies is critical. Combining targeted therapy and immunotherapy holds the potential for comprehensive therapeutic effects. Additionally, biomarker-based individualized ICI treatment strategies offer promise in predicting treatment response and guiding personalized patient care. Future research should explore emerging ICI treatment methods to optimize HCC immunotherapy. This review provides an overview of ICIs as a new treatment for HCC, demonstrating some success in promoting the tumor immune response. However, drug resistance and adverse reactions remain important considerations that must be addressed. As tailored treatment plans evolve, the prospect of immunotherapy for HCC is expected to grow, offering new opportunities for improved patient outcomes.

Clear cell renal cell carcinoma: immunological significance of alternative splicing signatures

Background

Renal cell carcinoma (RCC) accounts for 90% of renal cancers, of which clear cell carcinoma (ccRCC) is the most usual histological type. The process of alternative splicing (AS) contributes to protein diversity, and the dysregulation of protein diversity may have a great influence on tumorigenesis. We developed a prognostic signature and comprehensively analyzed the role of tumor immune microenvironment (TIME) and immune checkpoint blocking (ICB) treatment in ccRCC.

Methods

To identify prognosis-related AS events, univariate Cox regression was used and functional annotation was performed using gene set enrichment analysis (GSEA). In this study, prognostic signatures were developed based on multivariate Cox, univariate Cox, and LASSO regression models. Moreover, to assess the prognostic value, the proportional hazards model, Kruskal-Wallis analysis, and ROC curves were used. To obtain a better understanding of TIME in ccRCC, the ESTIMATE R package, single sample gene set enrichment analysis (ssGSEA) algorithm, CIBERSORT method, and the tumor immune estimation resource (TIMER) were applied. The database was searched to verify the expression of C4OF19 in tumor and normal samples. Regulatory networks for AS-splicing factors (SFs) were visualized using Cytoscape 3.9.1.

Results

There were 9,347 AS cases associated with the survival of ccRCC patients screened. A total of eight AS prognostic signatures were developed with stable prognostic predictive accuracy based on splicing subtypes. In addition, a qualitative prognostic nomogram was developed, and the prognostic prediction showed high effectiveness. In addition, we found that the combined signature was significantly associated with the diversity of TIME and ICB treatment-related genes. C4ORF19 might become an important prognostic factor for ccRCC. Finally, the AS-SF regulatory network was established to clearly reveal the potential function of SFs.

Conclusion

We found novel and robust indicators (i.e., risk signature, prognostic nomogram, etc.) for the prognostic prediction of ccRCC. A new and reliable prognostic nomogram was established to quantitatively predict the clinical outcome. The AS-SF networks could provide a new way for the study of potential regulatory mechanisms, and the important roles of AS events in the context of TIME and immunotherapy efficiency were exhibited. C4ORF19 was found to be a vital gene in TIME and ICB treatment.