Tumor-associated macrophage-derived exosomes transmitting miR-193a-5p promote the progression of renal cell carcinoma via TIMP2-dependent vasculogenic mimicry

Chromosomal 3p loss and 8q gain drive vasculogenic mimicry via HIF-2α and VE-cadherin activation in uveal melanoma

Uveal melanoma (UM) is the most common primary intraocular malignant tumor in adults and is where Vasculogenic Mimicry (VM) was first described. VM enables aggressive cancer cells to independently form blood networks, complicating treatment for patients exhibiting VM. Previous studies linked VE-Cadherin phosphorylation at Y658 to gene expression via Focal Adhesion Kinase (FAK), enhancing the Kaiso/β-catenin/TCF-4 complex associated with VE-Cadherin and thereby promoting VM. Recently, an allosteric HIF-2α inhibitor (Belzutifan) was FDA-approved for VHL-associated ccRCCs. In this research, we elucidate the primary causes of VM formation in UM patients with chromosome 3p loss and chromosome 8q gain, identifying VHL, BAP1, and FAK as important factors driving VM and worsening prognosis. These factors promote abnormal activation of HIF-2α and VE-Cadherin under basal hypoxic conditions, leading to VM formation. Cytoscan 750k experiments on the MUM 2B cell line reveal a loss of chromosome 3p, where the VHL, BAP1, and CTNNB1 genes are located, and a gain of chromosome 8q (FAK), whereas the MUM 2C cell line shows a gain of chromosome 3p. This provides an outstanding cross-sectional model from patient samples to established cell lines for VM studies. LC-MS experiments demonstrate that VE-Cad/ENG expression is related to FAK activity in UM cell lines. Finally, using a combination of Belzutifan (HIF-2α inhibitor) and FAK inhibitor (FAKi), we observed a significant reduction in UM xenografts. Our results lead us to propose combining Belzutifan and FAKi as a personalized treatment strategy for UM patients. This approach inhibits VM formation and counters the initial hypoxic conditions resulting from chromosome 3p loss and chromosome 8q gain in UM patients, instilling confidence in the potential of this treatment strategy.

Epigenetic regulation of macrophage function in kidney disease: New perspective on the interaction between epigenetics and immune modulation

The interaction between renal intrinsic cells and macrophages plays a crucial role in the onset and progression of kidney diseases. In recent years, epigenetic mechanisms such as DNA methylation, histone modification, and non-coding RNA regulation have become essential windows for understanding these processes. This review focuses on how renal intrinsic cells (including tubular epithelial cells, podocytes, and endothelial cells), renal cancer cells, and mesenchymal stem cells influence the function and polarization status of macrophages through their own epigenetic alterations, and how the epigenetic regulation of macrophages themselves responds to kidney damage, thus participating in renal inflammation, fibrosis, and repair. Moreover, therapeutic studies targeting these epigenetic interaction mechanisms have found that the application of histone deacetylase inhibitors, histone methyltransferase inhibitors, various nanomaterials, and locked nucleic acids against non-coding RNA have positive effects on the treatment of multiple kidney diseases. This review summarizes the latest research advancements in these epigenetic regulatory mechanisms and therapies, providing a theoretical foundation for further elucidating the pathogenesis of kidney diseases and the development of novel therapeutic strategies.

Rg3 inhibits hypoxia-induced tumor exosomes from boosting pancreatic cancer vasculogenic mimicry through the HIF-1α/LARS1/mTOR axis

BACKGROUND

Pancreatic cancer (PC), characterized by a poor prognosis, can utilize hypoxia to activate vasculogenic mimicry (VM) and facilitate metastasis. Exosomes serve as crucial mediators in this hypoxic environment. Our previous studies demonstrated that Rg3 could counteract VM by modulating the impact of PC-derived exosomes.

AIM

This study focuses on the carcinogenic mechanism of PC in a hypoxic environment.

METHODS

Exosomes from PANC-1 and BxPC-3 cells under normoxic or hypoxic conditions were isolated and characterized by western blot (WB) and nanoparticle trafficking analysis. These PC cells' VM potential was assessed through tube formation and WB. Molecular mechanisms were explored using proteomics analysis, bioinformatics analysis, and the gain- and loss-of-function studies, and the efficacy of Rg3 targeting these exosomes was examined in vitro and in vivo.

RESULTS

Exosomes from PANC-1 and BxPC-3 cells enhanced VM formation in PC cells under hypoxic conditions. Proteomics analysis revealed that these exosomes involved the HIF-1α/LARS1/mTOR axis. Hypoxia-activated HIF-1α led to high expression of LARS1 in PC cell exosomes, which were uptaken by recipient PC cells activating the mTOR signaling and promoting VM formation. Interaction between HIF-1α and LARS1 was further confirmed. In vitro and in vivo experiments demonstrated that Rg3 can diminish VM formation of PC cells triggered by the LARS1/mTOR axis in PC-derived exosomes under hypoxic conditions, improving the therapeutic effect of Rg3.

CONCLUSIONS

Our findings revealed a novel mechanism through which Rg3 inhibits VM in PC by modulating hypoxia-induced tumor exosomes, offering novel experimental insights for PC treatment.

Cinobufagin modulates vasculogenic mimicry and tumor-associated macrophages to inhibit ovarian cancer progression

BACKGROUND

Ovarian cancer is among the most prevalent malignant tumors affecting women. While conventional therapies like surgery do provide some measure of disease control, they are accompanied by evident side effects that may readily result in drug resistance. Cinobufagin (HCS) is a water-soluble active component extracted from the dried skin of the Bufo gargarizans. Clinical studies have demonstrated its significant anti-tumor effects.

METHODS

Transcriptome sequencing identified Forkhead Box S1 (FOXS1)-related targets, and Western blot analysis evaluated the expression levels of vasculogenic mimicry (VM)-related proteins and pathway proteins after cinobufagin intervention. Immunofluorescence and ELISA were used to detect the effects of cinobufagin on M1 and M2 macrophage markers. Additionally, a co-culture model of Skov3 cells and macrophages was established to study the effects of cinobufagin on tumor-associated macrophage polarization.

RESULTS

Cinobufagin significantly inhibited the growth of Skov3 ovarian cancer cells both in vitro and in vivo. Additionally, cinobufagin decreased the expression levels of VM-related proteins, thereby affecting vasculogenesis both in vitro and in vivo. Transcriptomic analysis revealed that the regulation of the FOXS1 gene contributed to this inhibitory effect. In the co-culture system, we found that cinobufagin inhibited IL-4-induced M2 macrophage polarization. Overexpression of FOXS1 in Skov3 cells enhanced the activity of the C-C motif chemokine ligand 2/receptor 2 (CCL2/CCR2) pathway, which was suppressed by cinobufagin, thus affecting the tumor microenvironment.

CONCLUSION

Cinobufagin suppressed vasculogenic mimicry by regulating the FOXS1 gene and inhibited M2 macrophage polarization through the CCL2/CCR2 pathway, thereby affecting the tumor microenvironment.

Single-cell analysis reveals that TCF7L2 facilitates the progression of ccRCC via tumor-associated macrophages

BACKGROUND

Tumor-associated macrophages (TAMs) play an important role in the recurrence and progression of clear cell renal cell carcinoma (ccRCC). However, the specified mechanism has not been elucidated.

METHODS

Single-cell and transcriptome analysis were applied to characterize the heterogeneity of TAMs. SCENIC would infer regulators of different subsets of TAMs. The CellChat algorithm was used to infer macrophage-tumor interaction networks, whereas pseudo-time traces were used to parse cell evolution and dynamics.

RESULTS

In this study, single-cell transcriptomic data of ccRCC were analyzed. Notably, the macrophages were clustered to select the cluster with a tendency toward M2-type TAM, which has an impact on the occurrence and metastasis of ccRCC. This macrophage cluster was defined as "TAM2". And this study revealed that TCF7L2 as a potential transcription factor regulating TAM2 transcriptional heterogeneity and differentiation. Pseudotime traces showed TCF7L2 trajectories during TAM2 cell cluster development. In addition, the results of cell interaction showed that TAM2 had the highest number and strength of interactions with cancer cells and endothelial cells. In vitro experiments, this study found that TCF7L2 was highly expressed in TAMs and promoted the polarization of macrophages to M2-type macrophages. And then overexpression of TCF7L2 in macrophages markedly promoted ccRCC invasion and proliferation.

CONCLUSION

TCF7L2 could play a key role in the progression of ccRCC via enhancing TAMs recruitment and M2-type polarization.

M2 macrophage-derived exosomes promote cell proliferation, migration and EMT of non-small cell lung cancer by secreting miR-155-5p

Tumor-associated macrophages (TAMs) are a type of highly plastic immune cells in the tumor microenvironment (TME), which can be classified into two main phenotypes: classical activated M1 macrophages and alternatively activated M2 macrophages. As previously reported, M2-polarized TAMs play critical role in promoting the progression of non-small cell lung cancer (NSCLC) via secreting exosomes, but the detailed mechanisms are still largely unknown. In the present study, the THP-1 monocytes were sequentially induced into M0 and M2-polarized macrophages, and the exosomes were obtained from M0 (M0-exos) and M2 (M2-exos) polarized macrophages, respectively, and co-cultured with NSCLC cells (H1299 and A549) to establish the exosomes-cell co-culture system in vitro. As it was determined by MTT assay, RT-qPCR and Transwell assay, in contrast with the M0-exos, M2-exos significantly promoted cell proliferation, migration and epithelial-mesenchymal transition (EMT) process in NSCLC cells. Next, through screening the contents in the exosomes, it was verified that miR-155-5p was especially enriched in the M2-exos, and M2-exos enhanced cancer aggressiveness and tumorigenesis in in vitro NSCLC cells and in vivo xenograft tumor-bearing mice models via delivering miR-155-5p. The detailed molecular mechanisms were subsequently elucidated, and it was found that miR-155-5p bound with HuR to increase the stability and expression levels of VEGFR2, which further activated the tumor-promoting PI3K/Akt/mTOR signal pathway, and M2-exos-enhanced cancer progression in NSCLC cells were apparently suppressed by downregulating VEGFR2 and PI3K inhibitor LY294002 co-treatment. Taken together, M2-polarized TAMs secreted miR-155-5p-containing exosomes to enhanced cancer aggressiveness of NSCLC by activating the VEGFR2/PI3K/Akt/mTOR pathway in a HuR-dependent manner.

New perspectives of exosomes in urologic malignancies - Mainly focus on biomarkers and tumor microenvironment

Bladder cancer (BCa) and renal cell carcinoma (RCC) are prevalent urologic malignancies (UM) characterized by high morbidity and frequent recurrence. Current diagnostic approaches, often invasive, often indicate an advanced disease stage. And the complex tumor microenvironment often promotes tumor progression and induces resistance to chemotherapy. Current diagnostic and therapeutic modalities often fail to achieve satisfactory outcomes for patients. Exosomes transport diverse cargoes, including cytokines, proteins, lipids, non-coding RNAs, and microRNAs, crucial for intercellular communication. Exosomes have shown potential as biomarkers for UM, participating in tumor progression, especially within the tumor microenvironment (TME), including tumor cell apoptosis, proliferation, migration, invasion, depletion of immune cell function, epithelial-mesenchymal transition (EMT), angiogenesis, and more.In this review, we summarize research advances related to exosomes in UM, focusing on the role of exosomes as biomarkers in bladder and renal cancer, highlighting their significance within the TME.

Revealing molecular mechanisms of early-onset tongue cancer by spatial transcriptomics

Tongue cancer at a young age demonstrates an increase in incidence, aggressiveness, and poor response to therapy. Classic etiological factors for head and neck tumors such as tobacco, alcohol, and human papillomavirus are not related to early-onset tongue cancer. Mechanisms of development and progression of this cancer remain unclear. In this study, we performed spatial whole-transcriptome profiling of tongue cancer in young adults compared with older patients. Nine patients with tongue squamous cell carcinoma (T2-3N0-1M0) were included and divided into two groups: younger (n = 5) and older than 45 years (n = 4). Formalin-fixed paraffin-embedded (FFPE) and fresh frozen (FF) samples of tumor tissue from 4 young and 5 older patients, respectively, were used for spatial transcriptomic profiling using the 10 × Genomics Visium. The findings were validated using SeekGene single cell full-length RNA sequencing (1 young vs 1 older patient) and TCGA data (15 young vs 70 older patients). As a result, we performed the first successful integration of spatial transcriptomics data from FF and FFPE samples and revealed distinctive features of tongue cancer in young adults. Oxidative stress, vascular mimicry, and MAPK and JAK-STAT pathways were enriched in early-onset tongue cancer. Tumor microenvironment demonstrated increased gene signatures corresponding to myeloid-derived suppressor cells, tumor-associated macrophages, and plasma cells. The invasive front was accompanied by vascular mimicry with arrangement of tumor-associated macrophages and aggregations of plasma cells and lymphocytes organized into tertiary lymphoid structures. Taken together, these results indicate that early-onset tongue cancer has distinct transcriptomic features and molecular mechanisms compared to older patients.

Circulating Extracellular Vesicles: An Effective Biomarker for Cancer Progression

Extracellular vesicles (EVs), the ubiquitous part of human biology, represent a small heterogenous, membrane-enclosed body that contains a diverse payload including genetic materials in the form of DNA, RNAs, small non-coding RNAs, etc. mostly mirroring their source of origin. Since, a vast majority of research has been conducted on how nucleic acids, proteins, lipids, and metabolites, associated with EVs can be effectively utilized to identify disease progression and therapeutic responses in cancer patients, EVs are increasingly being touted as valuable and reliable identifiers of cancer biomarkers in liquid biopsies. However, the lack of comprehensive clinical validation and effective standardization protocols severely limits its applications beyond the laboratories. The present review focuses on understanding the role of circulating EVs in different cancers and how they could potentially be treated as cancer biomarkers, typically due to the presence of bioactive molecules such as small non-coding RNAs, RNAs, DNA, proteins, etc., and their utilization for fine-tuning therapies. Here, we provide a brief general biology of EVs including their classification and subsequently discuss the source of circulatory EVs, the role of their associated payload as biomarkers, and how different cancers affect the level of circulatory EVs population.

Vasculogenic mimicry triggers early recidivation and resistance to adjuvant therapy in esophageal cancer

OBJECTIVE

To investigate the impact of vasculogenic mimicry (VM) and postoperative adjuvant therapy on the prognosis and survival of patients with esophageal squamous cell carcinoma (ESCC), as well as to assess whether VM affects the clinical benefit of postoperative adjuvant therapy.

METHODS

This single-center retrospective analysis included patients who underwent radical surgery for ESCC, which was documented in the medical record system. The presence or absence of VM in surgical specimens was determined using double staining with PAS/CD31. Stratification was applied based on adjuvant therapy and VM status. Survival curves and COX modeling were used to analyze the impact of the presence or absence of VM on the benefit of adjuvant therapy and the survival prognosis of patients.

RESULTS

VM-positive patients were more prone to postoperative recurrence and metastasis. VM was identified as an independent risk factor for progression-free survival (PFS) (p < 0.001, 95% CI:1.809-3.852) and overall survival (OS) (p < 0.001, 95% CI:1.603-2.786) in postoperative ESCC. Postoperative adjuvant therapy significantly prolonged PFS (p = 0.008) and OS time (p < 0.001) in patients with stage II and III ESCC, with concurrent chemoradiotherapy being the most effective. However, the presence of VM significantly reduced the benefits of postoperative adjuvant therapy (p < 0.001).

CONCLUSION

VM negatively impacts the prognosis of postoperative ESCC patients and reduces the efficacy of postoperative adjuvant therapy.

Exosome in renal cell carcinoma progression and implications for targeted therapy

Renal cell carcinoma is a urological malignancy with a high metastatic rate, while targeted therapy for renal cell carcinoma still has much room for improvement. Some cutting-edge researches have focused on exosome in cancer treatment and there are some breakthroughs in breast cancer, lung cancer, and pancreatic cancer. Up to now, exosome in renal cell carcinoma progression and implications for targeted therapy has been under research by scientists. In this review, we have summarized the structure, formation, uptake, functions, and detection of exosomes, classified the mechanisms of exosomes that cause renal cell carcinoma progression, and listed the promising utilization of exosomes in targeted therapy for renal cell carcinoma. In all, based on the mechanisms of exosomes causing renal cell carcinoma progression and borrowing the successful experience from renal cell carcinoma models and other cancers, exosomes will possibly be a promising target for therapy in renal cell carcinoma in the foreseeable future.

Molecular understanding and clinical aspects of tumor-associated macrophages in the immunotherapy of renal cell carcinoma

Renal cell carcinoma (RCC) is one of the most common tumors that afflicts the urinary system, accounting for 90-95% of kidney cancer cases. Although its incidence has increased over the past decades, its pathogenesis is still unclear. Tumor-associated macrophages (TAMs) are the most prominent immune cells in the tumor microenvironment (TME), comprising more than 50% of the tumor volume. By interacting with cancer cells, TAMs can be polarized into two distinct phenotypes, M1-type and M2-type TAMs. In the TME, M2-type TAMs, which are known to promote tumorigenesis, are more abundant than M1-type TAMs, which are known to suppress tumor growth. This ratio of M1 to M2 TAMs can create an immunosuppressive environment that contributes to tumor cell progression and survival. This review focused on the role of TAMs in RCC, including their polarization, impacts on tumor proliferation, angiogenesis, invasion, migration, drug resistance, and immunosuppression. In addition, we discussed the potential of targeting TAMs for clinical therapy in RCC. A deeper understanding of the molecular biology of TAMs is essential for exploring innovative therapeutic strategies for the treatment of RCC.

Tumor-associated macrophages derived exosomes; from pathogenesis to therapeutic opportunities

Tumor-associated macrophages (TAMs) exert profound influences on cancer progression, orchestrating a dynamic interplay within the tumor microenvironment. Recent attention has focused on the role of TAM-derived exosomes, small extracellular vesicles containing bioactive molecules, in mediating this intricate communication. This review comprehensively synthesizes current knowledge, emphasizing the diverse functions of TAM-derived exosomes across various cancer types. The review delves into the impact of TAM-derived exosomes on fundamental cancer hallmarks, elucidating their involvement in promoting cancer cell proliferation, migration, invasion, and apoptosis evasion. By dissecting the molecular cargo encapsulated within these exosomes, including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and proteins, the review uncovers key regulatory mechanisms governing these effects. Noteworthy miRNAs, such as miR-155, miR-196a-5p, and miR-221-3p, are highlighted for their pivotal roles in mediating TAM-derived exosomal communication and influencing downstream targets. Moreover, the review explores the impact of TAM-derived exosomes on the immune microenvironment, particularly their ability to modulate immune cell function and foster immune evasion. The discussion encompasses the regulation of programmed cell death ligand 1 (PD-L1) expression and subsequent impairment of CD8 + T cell activity, unraveling the immunosuppressive effects of TAM-derived exosomes. With an eye toward clinical implications, the review underscores the potential of TAM-derived exosomes as diagnostic markers and therapeutic targets. Their involvement in cancer progression, metastasis, and therapy resistance positions TAM-derived exosomes as key players in reshaping treatment strategies. Finally, the review outlines future directions, proposing avenues for targeted therapies aimed at disrupting TAM-derived exosomal functions and redefining the tumor microenvironment.

The role of extracellular vesicles in immune cell exhaustion and resistance to immunotherapy

INTRODUCTION

Extracellular vesicles (EVs) are membrane-bound nanoparticles for intercellular communication. Subtypes of EVs, namely exosomes and microvesicles transfer diverse, bioactive cargo to their target cells and eventually interfere with immune responses. Despite being a promising approach, cancer immunotherapy currently faces several challenges including immune resistance. EVs secreted from various sources in the tumor microenvironment provoke immune cell exhaustion and lower the efficacy of immunological treatments, such as CAR T cells and immune checkpoint inhibitors.

AREAS COVERED

This article goes through the mechanisms of action of various types of EVs in inhibiting immune response and immunotherapies, and provides a comprehensive review of EV-based treatments.

EXPERT OPINION

By making use of the distinctive features of EVs, natural or modified EVs are innovatively utilized as novel cancer therapeutics. They are occasionally coupled with currently established treatments to overcome their inadequacies. Investigating the properties and interactions of EVs and EV-based treatments is crucial for determining future steps in cancer therapeutics.

M2 Tumor-Associated Macrophages-Derived Exosomal MALAT1 Promotes Glycolysis and Gastric Cancer Progression

M2-polarized tumor-associated macrophages (M2 TAMs) promote cancer progression. Exosomes mediate cellular communication in the tumor microenvironment (TME). However, the roles of exosomes from M2 TAMs in gastric cancer progression are unclear. Herein, it is reported that M2 TAMs-derived exosomes induced aerobic glycolysis in gastric cancer cells and enhanced their proliferation, metastasis, and chemoresistance in a glycolysis-dependent manner. It is identified that MALAT1 (metastasis-associated lung adenocarcinoma transcript 1) is enriched in M2 TAM exosomes and confirmed that MALAT1 transfer from M2 TAMs to gastric cancer cells via exosomes mediates this effect. Mechanistically, MALAT1 interacted with the δ-catenin protein and suppressed its ubiquitination and degradation by β-TRCP. In addition, MALAT1 upregulated HIF-1α expression by acting as a sponge for miR-217-5p. The activation of β-catenin and HIF-1α signaling pathways by M2 TAM exosomes collectively led to enhanced aerobic glycolysis in gastric cancer cells. Finally, a dual-targeted inhibition of MALAT1 in both gastric cancer cells and macrophages by exosome-mediated delivery of siRNA remarkably suppressed gastric cancer growth and improved chemosensitivity in mouse tumor models. Taken together, these results suggest that M2 TAMs-derived exosomes promote gastric cancer progression via MALAT1-mediated regulation of glycolysis. The findings offer a potential target for gastric cancer therapy.

Identification of circulating miRNAs as fracture-related biomarkers

Fracture non-unions affect many patients worldwide, however, known risk factors alone do not predict individual risk. The identification of novel biomarkers is crucial for early diagnosis and timely patient treatment. This study focused on the identification of microRNA (miRNA) related to the process of fracture healing. Serum of fracture patients and healthy volunteers was screened by RNA sequencing to identify differentially expressed miRNA at various times after injury. The results were correlated to miRNA in the conditioned medium of human bone marrow mesenchymal stromal cells (BMSCs) during in vitro osteogenic differentiation. hsa-miR-1246, hsa-miR-335-5p, and miR-193a-5p were identified both in vitro and in fracture patients and their functional role in direct BMSC osteogenic differentiation was assessed. The results showed no influence of the downregulation of the three miRNAs during in vitro osteogenesis. However, miR-1246 may be involved in cell proliferation and recruitment of progenitor cells. Further studies should be performed to assess the role of these miRNA in other processes relevant to fracture healing.

Pan-cancer dissection of vasculogenic mimicry characteristic to provide potential therapeutic targets

Introduction

Vasculogenic mimicry (VM) represents a novel form of tumor angiogenesis that is associated with tumor invasiveness and drug resistance. However, the VM landscape across cancer types remains poorly understood. In this study, we elucidate the characterizations of VM across cancers based on multi-omics data and provide potential targeted therapeutic strategies.

Methods

Multi-omics data from The Cancer Genome Atlas was used to conduct comprehensive analyses of the characteristics of VM related genes (VRGs) across cancer types. Pan-cancer vasculogenic mimicry score was established to provide a depiction of the VM landscape across cancer types. The correlation between VM and cancer phenotypes was conducted to explore potential regulatory mechanisms of VM. We further systematically examined the relationship between VM and both tumor immunity and tumor microenvironment (TME). In addition, cell communication analysis based on single-cell transcriptome data was used to investigate the interactions between VM cells and TME. Finally, transcriptional and drug response data from the Genomics of Drug Sensitivity in Cancer database were utilized to identify potential therapeutic targets and drugs. The impact of VM on immunotherapy was also further clarified.

Results

Our study revealed that VRGs were dysregulated in tumor and regulated by multiple mechanisms. Then, VM level was found to be heterogeneous among different tumors and correlated with tumor invasiveness, metastatic potential, malignancy, and prognosis. VM was found to be strongly associated with epithelial-mesenchymal transition (EMT). Further analyses revealed cancer-associated fibroblasts can promote EMT and VM formation. Furthermore, the immune-suppressive state is associated with a microenvironment characterized by high levels of VM. VM score can be used as an indicator to predict the effect of immunotherapy. Finally, seven potential drugs targeting VM were identified.

Conclusion

In conclusion, we elucidate the characteristics and key regulatory mechanisms of VM across various cancer types, underscoring the pivotal role of CAFs in VM. VM was further found to be associated with the immunosuppressive TME. We also provide clues for the research of drugs targeting VM. Our study provides an initial overview and reference point for future research on VM, opening up new avenues for therapeutic intervention.

The vasculogenic mimicry related signature predicts the prognosis and immunotherapy response in renal clear cell carcinoma

BACKGROUND

Clear cell carcinoma of the kidney is a common urological malignancy characterized by poor patient prognosis and treatment outcomes. Modulation of vasculogenic mimicry in tumor cells alters the tumor microenvironment and the influx of tumor-infiltrating lymphocytes, and the combination of its inducers and immune checkpoint inhibitors plays a synergistic role in enhancing antitumor effects.

METHODS

We downloaded the data from renal clear cell carcinoma samples and vasculogenic mimicry-related genes to establish a new vasculogenic mimicry-related index (VMRI) using a machine learning approach. Based on VMRI, patients with renal clear cell carcinoma were divided into high VMRI and low VMRI groups, and patients' prognosis, clinical features, tumor immune microenvironment, chemotherapeutic response, and immunotherapeutic response were systematically analyzed. Finally, the function of CDH5 was explored in renal clear cell carcinoma cells.

RESULTS

VMRI can be used for prognostic and immunotherapy efficacy prediction in a variety of cancers, which consists of four vasculogenic mimicry-related genes (CDH5, MMP9, MAPK1, and MMP13), is a reliable predictor of survival and grade in patients with clear cell carcinoma of the kidney and has been validated in multiple external datasets. We found that the high VMRI group presented higher levels of immune cell infiltration, which was validated by pathological sections. We performed molecular docking prediction of vasculogenic mimicry core target proteins and identified natural small molecule drugs with the highest affinity for the target protein. Knockdown of CDH5 inhibited the proliferation and migration of renal clear cell carcinoma.

CONCLUSIONS

The VMRI identified in this study allows for accurate prognosis assessment of patients with renal clear cell carcinoma and identification of patient populations that will benefit from immunotherapy, providing valuable insights for future precision treatment of patients with renal clear cell carcinoma.

Ginsenoside Rg3 suppresses vasculogenic mimicry by impairing DVL3-maintained stemness via PAAD cell-derived exosomal miR-204 in pancreatic adenocarcinoma

BACKGROUND

Vasculogenic mimicry (VM) is an angiogenesis-independent process that potentially contributes to the poor clinical outcome of anti-angiogenesis therapy in multiple malignant cancers, including pancreatic adenocarcinoma (PAAD). Several studies have shown that ginsenoside Rg3, a bioactive component of ginseng, holds considerable potential for cancer treatment. Our previous work has proved that Rg3 can inhibit VM formation in PAAD. However, its underlying mechanism remains unclear.

PURPOSE

To explore the underlying mechanism by which Rg3 affects VM formation in PAAD.

METHODS

We first investigated the effects of Rg3 on the cellular phenotypes of two PAAD cell lines (SW-1990 and PCI-35), and the expression of EMT- and stemness-related proteins. SW-1990 cells were adopted to construct xenograft models, and the anti-tumor effects of Rg3 in vivo were validated. Subsequently, we isolated the exosomes from the two PAAD cell lines with Rg3 treatment or not, and explored whether Rg3 regulated VM via PAAD cell-derived exosomes. MiRNA sequencing, clinical analysis, and rescue experiments were performed to investigate whether and which miRNA was involved. Subsequently, the target gene of miRNA was predicted using the miRDB website (https://mirdb.org/), and rescue experiments were further conducted to validate those in vitro and in vivo.

RESULTS

Rg3 indeed exhibited excellent anti-tumor effects both in vitro and in vivo, with inhibitory effects on EMT and stemness of PAAD cells. More interestingly, Rg3-treated PAAD cell-derived exosomes suppressed the tube-forming ability of HUVEC and PAAD cells, with a decrease in stemness-related protein expression, indicating that Rg3 inhibited both angiogenesis and VM processes. Subsequently, we found that Rg3 induced the up-regulation of miR-204 in PAAD cell-derived exosomes, and miR-204 alone inhibited tube and sphere formation abilities of PAAD cells like exosomes. Specifically, miR-204 down-regulated DVL3 expression, which was involved in regulating cancer cell stemness, and ultimately affected VM. The in vivo experiments further indicated that Rg3-treated SW-1990 cell-derived exosome-inhibited tumor growth, VM formation, and stemness-related protein expression can be abrogated by DVL3 overexpression.

CONCLUSION

Ginsenoside Rg3 increased the PAAD cell-derived exosomal miR-204 levels, which subsequently inhibited its target genes DVL3 expression in the receptor PAAD cells, and the down-regulated DVL3 broke stemness maintenance, ultimately suppressing VM formation of PAAD. Our findings revealed a novel mechanism by which Rg3 exerted its anti-tumor activity in PAAD via inhibiting VM, and provided a promising strategy to make up for the deficiency of anti-angiogenesis therapy in cancer.

Diagnostic, prognostic, and therapeutic potential of exosomal microRNAs in renal cancer

Renal cell carcinoma (RCC) arises from the tubular epithelial cells of the nephron. It has the highest mortality rate among urological cancers. There are no effective therapeutic approaches and no non-invasive biomarkers for diagnosis and follow-up. Thus, suitable novel biomarkers and therapeutic targets are essential for improving RCC diagnosis/prognosis and treatment. Circulating exosomes such as exosomal microRNAs (Exo-miRs) provide non-invasive prognostic/diagnostic biomarkers and valuable therapeutic targets, as they can be easily isolated and quantified and show high sensitivity and specificity. Exosomes secreted by an RCC can exhibit alterations in the miRs' profile that may reflect the cellular origin and (patho)physiological state, as a ''signature'' or ''fingerprint'' of the donor cell. It has been shown that the transportation of renal-specific miRs in exosomes can be rapidly detected and measured, holding great potential as biomarkers in RCC. The present review highlights the studies reporting tumor microenvironment-derived Exo-miRs with therapeutic potential as well as circulating Exo-miRs as potential diagnostic/prognostic biomarkers in patients with RCC.

Tumorigenic and tumoricidal properties of exosomes in cancers; a forward look

In recent decades, emerging data have highlighted the critical role of extracellular vesicles (EVs), especially (exosomes) Exos, in the progression and development of several cancer types. These nano-sized vesicles are released by different cell lineages within the cancer niche and maintain a suitable platform for the interchange of various signaling molecules in a paracrine manner. Based on several studies, Exos can transfer oncogenic factors to other cells, and alter the activity of immune cells, and tumor microenvironment, leading to the expansion of tumor cells and metastasis to the remote sites. It has been indicated that the cell-to-cell crosstalk is so complicated and a wide array of factors are involved in this process. How and by which mechanisms Exos can regulate the behavior of tumor cells and non-cancer cells is at the center of debate. Here, we scrutinize the molecular mechanisms involved in the oncogenic behavior of Exos released by different cell lineages of tumor parenchyma. Besides, tumoricidal properties of Exos from various stem cell (SC) types are discussed in detail.

Serum Exosome-Derived microRNA-193a-5p and miR-381-3p Regulate Adenosine 5'-Monophosphate-Activated Protein Kinase/Transforming Growth Factor Beta/Smad2/3 Signaling Pathway and Promote Fibrogenesis

INTRODUCTION

Liver fibrosis results from chronic liver injury and inflammation, often leading to cirrhosis, liver failure, portal hypertension, and hepatocellular carcinoma. Progress has been made in understanding the molecular mechanisms underlying hepatic fibrosis; however, translating this knowledge into effective therapies for disease regression remains a challenge, with considerably few interventions having entered clinical validation. The roles of exosomes during fibrogenesis and their potential as a therapeutic approach for reversing fibrosis have gained significant interest. This study aimed to investigate the association between microRNAs (miRNAs) derived from serum exosomes and liver fibrosis and to evaluate the effect of serum exosomes on fibrogenesis and fibrosis reversal, while identifying the underlying mechanism.

METHODS

Using serum samples collected from healthy adults and paired histologic patients with advanced fibrosis or cirrhosis, we extracted human serum exosomes by ultrahigh-speed centrifugation. Transcriptomic analysis was conducted to identify dysregulated exosome-derived miRNAs. Liver fibrosis-related molecules were determined by qRT-PCR, Western blot, Masson staining, and immunohistochemical staining. In addition, we analyzed the importance of serum exosome-derived miRNA expression levels in 42 patients with advanced fibrosis or cirrhosis.

RESULTS

Exosome-derived miR-193a-5p and miR-381-3p were associated with fibrogenesis, as determined by transcriptomic screening. Compared with healthy control group, the high expression of serum exosome-derived miR-193a-5p and miR-381-3 in chronic hepatitis B (n = 42) was closely associated with advanced liver fibrosis and cirrhosis. In vitro , exosome-derived miRNA-193a-5p and miR-381-3p upregulated the expression of α-smooth muscle actin, collagen 1a1, and tissue inhibitors of metalloproteinase 1 in the human hepatic stellate cell line at both mRNA and protein levels.

DISCUSSION

Serum exosome-derived miR-193a-5p and miR-381-3p regulated the adenosine 5'-monophosphate-activated protein kinase/transforming growth factor beta/Smad2/3 signaling pathway and promoted fibrogenesis.

LncRNA HEIH modulates the proliferation, migration, and invasion of hepatocellular carcinoma cells by regulating the miR-193a-5p/CDK8 axis

Background

Hepatocellular carcinoma (HCC), a malignant tumor with a high mortality rate, is a serious problem worldwide. This research sought to examine how long non-coding RNA (lncRNA) high expression in hepatocellular carcinoma (HEIH) affects the development and progression of HCC.

Methods

The expression of HEIH in HCC patients and HCC cell lines was measured by quantitative real-time polymerase chain reaction (qRT-PCR). Additionally, HEIH was knocked down, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide, wound-healing and transwell assays were conducted to evaluate the effects of HEIH on the proliferation, migration, and invasion of the HCC cells, respectively. A xenografted mice model was constructed to investigate the function of HEIH on HCC tumorigenesis in vivo. The interactions among HEIH, microRNA (miR)-193a-5p and cyclin-dependent kinase 8 (CDK8) were also investigated by dual luciferase reporter (DLR) gene and RNA immunoprecipitation (RIP) assays.

Results

HEIH was highly expressed in HCC tissues, and was correlated with advanced TNM stage and the absence of vascular invasion. The in vitro experiments showed that silencing HEIH restrained the viability, migration, and invasion of HCC cells, and hampered xenograft tumor growth in vivo. Additionally, HEIH was shown to bind directly to microRNA 193a-5p (miR-193a-5p) and facilitate the expression of the target gene CDK8 in the HCC cells. CDK8 overexpression and miR-193a-5p silencing attenuated the effects of si-HEIH-induced inhibition on the proliferation, migration, and invasion of HCC cells.

Conclusions

Silencing HEIH restrained the proliferation, migration, and invasion of HCC cells via the miR-193a-5p/CDK8 axis.

Integration analysis of PLAUR as a sunitinib resistance and macrophage related biomarker in ccRCC, an in silicon and experimental study

Sunitinib remains the preferred systemic treatment option for specific patients with advanced RCC who are ineligible for immune therapy. However, it's essential to recognize that Sunitinib fails to elicit a favourable response in all patients. Moreover, most patients eventually develop resistance to Sunitinib. Therefore, identifying new targets associated with Sunitinib resistance is crucial. Utilizing multiple datasets from public cohorts, we conducted an exhaustive analysis and identified a total of 8 microRNAs and 112 mRNAs displaying significant expression differences between Sunitinib responsive and resistant groups. A particular set of six genes, specifically NIPSNAP1, STK40, SDC4, NEU1, TBC1D9, and PLAUR, were identified as highly significant via WGCNA. To delve deeper into the resistance mechanisms, we performed additional investigations using cell, molecular, and flow cytometry tests. These studies confirmed PLAUR's pivotal role in fostering Sunitinib resistance, both in vitro and in vivo. Our findings suggest that PLAUR could be a promising therapeutic target across various cancer types. In conclusion, this investigation not only uncovers vital genes and microRNAs associated with Sunitinib resistance in RCC but also introduces PLAUR as a prospective therapeutic target for diverse cancers. The outcomes contribute to advancing personalized healthcare and developing superior therapeutic strategies.Communicated by Ramaswamy H. Sarma.

Vasculogenic mimicry-associated novel gene signature predicted prognosis and response to immunotherapy in lung adenocarcinoma

BACKGROUNDS

It was highlighted by recent studies on the biological significance of vasculogenic mimicry (VM) in tumorigenicity and progression. However, it is unclear whether VM also plays a potential role in immune regulation and tumor microenvironment (TME) formation.

METHODS

To identify patterns of VM alterations and VM-associated genetic features in non-small cell lung adenocarcinoma, we have screened 309 VM regulators and performed consensus molecular typing by the NMF algorithm. The ssGSEA and CIBORSORT algorithms were employed to measure the relative infiltration of distinct immune cell subpopulations. Individual tumors with immune responses were evaluated for alteration patterns of VM with typing-based differential genes.

RESULTS

In 490 LUAD samples, two distinctive VM alteration patterns connected to different clinical outcomes and biochemical pathways were established. TME characterization showed that the observed VM patterns were primarily saturated with cell proliferation and metabolic pathways and higher in immune cell infiltration of the C1 type. Vasculogenic mimicry-related genes (VMRG) risk scores were constructed to divide patients with lung adenocarcinoma into subgroups with high and low scores. Patients with lower scores had better immunological scores and longer survival times. Upon further investigation, higher scores were positively correlated with higher tumor mutation burden (TMB), M1-type macrophages and immune checkpoint molecules. Nevertheless, in two other immunotherapy cohorts, individuals with lower scores had enhanced immune responses and long-lasting therapeutic benefits. Finally, we monitored the ANLN gene from the VMRG model, which was highly expressed in lung adenocarcinoma tissues and negatively correlated with prognosis; it was also highly expressed in lung adenocarcinoma cell lines, and knockdown of ANLN elicited low expression of VEGFA, MMP2 and MMP9.

CONCLUSION

This study highlights that VM modifications are significantly associated with the diversity and complexity of TME, revealing new features of the immune microenvironment in lung adenocarcinoma and providing a new strategy for immunotherapy. Screening ANLN as a critical target for vasculogenic mimicry in lung adenocarcinoma provides a novel perspective for the targeted treatment of lung adenocarcinoma.

The categorizations of vasculogenic mimicry in clear cell renal cell carcinoma unveil inherent connections with clinical and immune features

Background: Clear cell renal cell carcinoma (ccRCC) stands as the prevailing variant kidney cancer in humans. Unfortunately, patients with disseminated RCC at diagnosis often have a diminished prognosis. Rapid tumor growth necessitates efficient blood supply for oxygen and nutrients, involving the circulation of blood from vessels to tumor tissues, facilitating tumor cell entry into the extracellular matrix. Vasculogenic mimicry (VM) significantly contributes to tumor growth and metastasis. Within this investigation, we identified vasculogenic mimicry-related genes (VMRGs) by analyzing data from 607 cases of kidney renal clear cell carcinoma (KIRC) in The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) database (https://www.ncbi.nlm.nih.gov/geo/). These findings offer insights into ccRCC progression and metastasis. Method: We identified VMRGs-related subtypes using consistent clustering methods. The signature of the VMRGs was created using univariate Cox regression and LASSO Cox regression analyses. To evaluate differences in immune cell infiltration, we employed ssGSEA. Afterwards, we created an innovative risk assessment model, known as the VM index, along with a nomogram to forecast the prognosis of ccRCC. Additionally, we verified the expression of an important gene related to VM, peroxiredoxin 2 (PRDX2), in tissue samples. Furthermore, we assessed the sensitivity to drugs in various groups by utilizing the pRRophetic R package. Results: Significant predictors of survival rates in both high- and low-risk groups of KIRC patients were identified as VMRGs. The independent prognostic factors for RCC were confirmed by both univariate and multivariate Cox regression analyses, validating VMRG risk signatures. Differences were observed in drug sensitivity, immune checkpoint expression, and responses to immune therapy between patients classified into high- and low-VMRG-risk groups. Our nomograms consistently demonstrated precise predictive capabilities. Finally, we experimentally verified PRDX2 expression levels and their impact on prognosis. Conclusion: The signature predicts patient prognosis and therapy response, laying the groundwork for future clinical strategies in treating ccRCC patients.

Exosome derived from tumor-associated macrophages: biogenesis, functions, and therapeutic implications in human cancers

Tumor-associated macrophages (TAMs), one of the most abundant immune cell types in the tumor microenvironment (TME), account for approximately 50% of the local hematopoietic cells. TAMs play an important role in tumorigenesis and tumor development through crosstalk between various immune cells and cytokines in the TME. Exosomes are small extracellular vesicles with a diameter of 50-150 nm, that can transfer biological information (e.g., proteins, nucleic acids, and lipids) from secretory cells to recipient cells through the circulatory system, thereby influencing the progression of various human diseases, including cancer. Recent studies have suggested that TAMs-derived exosomes play crucial roles in malignant cell proliferation, invasion, metastasis, angiogenesis, immune responses, drug resistance, and tumor metabolic reprogramming. TAMs-derived exosomes have the potential to be targeted for tumor therapy. In addition, the abnormal expression of non-coding RNAs and proteins in TAMs-derived exosomes is closely related to the clinicopathological features of patients with cancer, and these exosomes are expected to become new liquid biopsy markers for the early diagnosis, prognosis, and monitoring of tumors. In this review, we explored the role of TAMs-derived exosomes in tumorigenesis to provide new diagnostic biomarkers and therapeutic targets for cancer prevention.

Tumor-associated macrophages: an effective player of the tumor microenvironment

Cancer progression is primarily caused by interactions between transformed cells and the components of the tumor microenvironment (TME). TAMs (tumor-associated macrophages) make up the majority of the invading immune components, which are further categorized as anti-tumor M1 and pro-tumor M2 subtypes. While M1 is known to have anti-cancer properties, M2 is recognized to extend a protective role to the tumor. As a result, the tumor manipulates the TME in such a way that it induces macrophage infiltration and M1 to M2 switching bias to secure its survival. This M2-TAM bias in the TME promotes cancer cell proliferation, neoangiogenesis, lymphangiogenesis, epithelial-to-mesenchymal transition, matrix remodeling for metastatic support, and TME manipulation to an immunosuppressive state. TAMs additionally promote the emergence of cancer stem cells (CSCs), which are known for their ability to originate, metastasize, and relapse into tumors. CSCs also help M2-TAM by revealing immune escape and survival strategies during the initiation and relapse phases. This review describes the reasons for immunotherapy failure and, thereby, devises better strategies to impair the tumor-TAM crosstalk. This study will shed light on the understudied TAM-mediated tumor progression and address the much-needed holistic approach to anti-cancer therapy, which encompasses targeting cancer cells, CSCs, and TAMs all at the same time.

Genes associated with inflammation for prognosis prediction for clear cell renal cell carcinoma: a multi-database analysis

Background

Clear cell renal cell carcinoma (ccRCC) is the largest subtype of kidney tumour, with inflammatory responses characterising all stages of the tumour. Establishing the relationship between the genes related to inflammatory responses and ccRCC may help the diagnosis and treatment of patients with ccRCC.

Methods

First, we obtained the data for this study from a public database. After differential analysis and Cox regression analysis, we obtained the genes for the establishment of a prognostic model for ccRCC. As we used data from multiple databases, we standardized all the data using the surrogate variable analysis (SVA) package to make the data from different sources comparable. Next, we used a least absolute shrinkage and selection operator (LASSO) regression to construct a prognostic model of genes related to inflammation. The data used for modelling and internal validation came from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) series (GSE29609) databases. ccRCC data from the International Cancer Genome Consortium (ICGC) database were used for external validation. Tumour data from the E-MTAB-1980 cohort were used for external validation. The GSE40453 and GSE53757 datasets were used to verify the differential expression of inflammation-related gene model signatures (IRGMS). The immunohistochemistry of IRGMS was queried through the Human Protein Atlas (HPA) database. After the adequate validation of the IRGM, we further explored its application by constructing nomograms, pathway enrichment analysis, immunocorrelation analysis, drug susceptibility analysis, and subtype identification.

Results

The IRGM can robustly predict the prognosis of samples from patients with ccRCC from different databases. The verification results show that nomogram can accurately predict the survival rate of patients. Pathway enrichment analysis showed that patients in the high-risk (HR) group were associated with a variety of tumorigenesis biological processes. Immune-related analysis and drug susceptibility analysis suggested that patients with higher IRGM scores had more treatment options.

Conclusions

The IRGMS can effectively predict the prognosis of ccRCC. Patients with higher IRGM scores may be better candidates for treatment with immune checkpoint inhibitors and have more chemotherapy options.

Advances in the research of exosomes in renal cell carcinoma: from mechanisms to applications

Renal cell carcinoma (RCC) is one of the most malignant urological tumors. Currently, there is a lack of molecular markers for early diagnosis of RCC. The 5-year survival rate for early-stage RCC is generally favorable; however, the prognosis takes a significant downturn when the tumor progresses to distant metastasis. Therefore, the identification of molecular markers for RCC is crucial in enhancing early diagnosis rates. Exosomes are a type of extracellular vesicle (EV) typically ranging in size from 30 nm to 150 nm, which contain RNA, DNA, proteins, lipids, etc. They can impact neighboring receptor cells through the autocrine or paracrine pathway, influence cellular communication, and regulate the local immune cells, consequently shaping the tumor immune microenvironment and closely associating with tumor development. The clinical application of exosomes as tumor markers and therapeutic targets has ignited significant interest within the research community. This review aims to provide a comprehensive summary of the advancements in exosome research within the context of RCC.

Therapeutic potential of vasculogenic mimicry in urological tumors

Angiogenesis is an essential process in the growth and metastasis of cancer cells, which can be hampered by an anti-angiogenesis mechanism, thereby delaying the progression of tumors. However, the benefit of this treatment modality could be restricted, as most patients tend to develop acquired resistance during treatment. Vasculogenic mimicry (VM) is regarded as a critical alternative mechanism of tumor angiogenesis, where studies have demonstrated that patients with tumors supplemented with VM generally have a shorter survival period and a poorer prognosis. Inhibiting VM may be an effective therapeutic strategy to prevent cancer progression, which could prove helpful in impeding the limitations of lone use of anti-angiogenic therapy when performed concurrently with other anti-tumor therapies. This review summarizes the mechanism of VM signaling pathways in urological tumors, i.e., prostate cancer, clear cell renal cell carcinoma, and bladder cancer. Furthermore, it also summarizes the potential of VM as a therapeutic strategy for urological tumors.

Live-imaging studies reveal how microclots and the associated inflammatory response enhance cancer cell extravasation

Previous clinical studies and work in mouse models have indicated that platelets and microclots might enable the recruitment of immune cells to the pre-metastatic cancer niche, leading to efficacious extravasation of cancer cells through the vessel wall. Here, we investigated the interaction between platelets, endothelial cells, inflammatory cells, and engrafted human and zebrafish cancer cells by live-imaging studies in translucent zebrafish larvae, and show how clotting (and clot resolution) act as foci and as triggers for extravasation. Fluorescent tagging in each lineage revealed their dynamic behaviour and potential roles in these events, and we tested function by genetic and drug knockdown of the contributing players. Morpholino knockdown of fibrinogen subunit α (fga) and warfarin treatment to inhibit clotting both abrogated extravasation of cancer cells. The inflammatory phenotype appeared fundamental, and we show that forcing a pro-inflammatory, tnfa-positive phenotype is inhibitory to extravasation of cancer cells.

Radiomics Correlation to CD68+ Tumor-Associated Macrophages in Clear Cell Renal Cell Carcinoma

INTRODUCTION

Renal cell carcinoma (RCC) is the ninth most common cancer worldwide, with clear cell RCC (ccRCC) being the most frequent histological subtype. The tumor immune microenvironment (TIME) of ccRCC is an important factor to guide treatment, but current assessments are tissue-based, which can be time-consuming and resource-intensive. In this study, we used radiomics extracted from clinically performed computed tomography (CT) as a noninvasive surrogate for CD68 tumor-associated macrophages (TAMs), a significant component of ccRCC TIME.

METHODS

TAM population was measured by CD68+/PanCK+ ratio and tumor-TAM clustering was measured by normalized K function calculated from multiplex immunofluorescence (mIF). A total of 1,076 regions on mIF slides from 78 patients were included. Radiomic features were extracted from multiphase CT of the ccRCC tumor. Statistical machine learning models, including random forest, Adaptive Boosting, and ElasticNet, were used to predict TAM population and tumor-TAM clustering.

RESULTS

The best models achieved an area under the ROC curve of 0.81 (95% CI: [0.69, 0.92]) for TAM population and 0.77 (95% CI: [0.66, 0.88]) for tumor-TAM clustering, respectively.

CONCLUSION

Our study demonstrates the potential of using CT radiomics-derived imaging markers as a surrogate for assessment of TAM in ccRCC for real-time treatment response monitoring and patient selection for targeted therapies and immunotherapies.

Four differentially expressed exosomal miRNAs as prognostic biomarkers and therapy targets in endometrial cancer: Bioinformatic analysis

Endometrial cancer (EC) is one of the most common gynecological malignancies worldwide. Accumulated evidence has demonstrated exosomes of cancer cells carry microRNAs (miRNAs) to nonmalignant cells to induce metastasis. Our study aimed to find possible biomarkers of EC. Data for miRNA expression related with exosome from EC patients were downloaded from The Cancer Genome Atlas database, and the miRNA expression profiles associated with exosomes of EC were downloaded from the National Center for Biotechnology Information. We used different algorithms to analyze the differential miRNA expression, infer the relative proportion of immune infiltrating cells, predict chemotherapy sensitivity, and comprehensively score each gene set to evaluate the potential biological function changes of different samples. The gene ontology analysis and Kyoto encyclopedia of genome genomics pathway analysis were performed for specific genes. A total of 13 differential miRNAs were identified, of which 4 were up-regulated. The 4 miRNAs, that is hsa-miR-17-3p, hsa-miR-99b-3p, hsa-miR-193a-5p, and hsa-miR-320d, were the hub exosomal miRNAs that were all closely related to the clinic phenotypes and prognosis of patients. This study preliminarily indicates that the 4 hub exosomal miRNAs (hsa-miR-17-3p, hsa-miR-99b-3p, hsa-miR-193a-5p, and hsa-miR-320d) could be used as prognostic biomarkers or therapy targets in EC. Further studies are required to make sure of their real feasibility and values in the EC clinic and the relative research.

Extracellular vesicles in renal cell carcinoma: challenges and opportunities coexist

Renal cell carcinoma (RCC) represents an extremely challenging disease in terms of both diagnosis and treatment. It poses a significant threat to human health, with incidence rates increasing at a yearly rate of roughly 2%. Extracellular vesicles (EVs) are lipid-based bilayer structures of membranes that are essential for intercellular interaction and have been linked to the advancement of RCC. This review provides an overview of recent studies on the role of EVs in RCC progression, including involvement in the interaction of tumor cells with M2 macrophages, mediating the generation of immune tolerance, and assuming the role of communication messengers in the tumor microenvironment leading to disease progression. Finally, the " troika " of EVs in RCC therapy is presented, including engineered sEVs' or EVs tumor vaccines, mesenchymal stem cell EVs therapy, and reduction of tumor-derived EVs secretion. In this context, we highlight the limitations and challenges of EV-based research and the prospects for future developments in this field. Overall, this review provides a comprehensive summary of the role of EVs in RCC and their potential as a viable pathway for the future treatment of this complex disease.

Role of microRNA carried by small extracellular vesicles in urological tumors

Small extracellular vesicles (sEVs) are minute vesicles secreted by various cells that are capable of transporting cargo, including microRNAs, between donor and recipient cells. MicroRNAs (miRNAs), small non-coding RNAs approximately 22 nucleotides in length, have been implicated in a wide array of biological processes, including those involved in tumorigenesis. Emerging evidence highlights the pivotal role of miRNAs encapsulated in sEVs in both the diagnosis and treatment of urological tumors, with potential implications in epithelial-mesenchymal transition, proliferation, metastasis, angiogenesis, tumor microenvironment and drug resistance. This review provides a brief overview of the biogenesis and functional mechanisms of sEVs and miRNAs, followed by a summarization of recent empirical findings on miRNAs encapsulated in sEVs from three archetypal urologic malignancies: prostate cancer, clear cell renal cell carcinoma, and bladder cancer. We conclude by underscoring the potential of sEV-enclosed miRNAs as both biomarkers and therapeutic targets, with a particular focus on their detection and analysis in biological fluids such as urine, plasma, and serum.

The Effects of circ_000558/miR-1225-5p/ARL4C on Regulating the Proliferation of Renal Cell Carcinoma Cells

Renal cell carcinoma (RCC) is one of the top ten tumors over the world. RCC is not sensitive to radiotherapy and chemotherapy. Therefore, it is necessary to find new targets for the treatment. CircRNAs are a special type of noncoding RNAs, which play important roles in many types of cancer. In this study, we found circ_000558 was upregulated in RCC cells, and it elevated the proliferation ability of RCC cells. The relationship between miR-1225-5p and circ_000558 or ARL4C was predicted via circBank and circular RNA interactome and confirmed by dual-luciferase reporter assay. Then, the effects of circ_000558/miR-1225-5p/ARL4C on RCC cell proliferation and apoptosis were assessed by CCK-8 assay. The results revealed that the knockdown of ARL4C significantly reduced RCC cell proliferation and overexpression of circ_000558 could significantly induce RCC cell proliferation after miR-1225-5p treatment further promoted the inhibitory ability of ARL4C knockdown. Overall, our study suggested that circ_000558/miR-1225-5p/ARL4C network was related to the RCC cell proliferation. This finding could provide new targets for the treatment and prognosis of RCC.

[Vasculogenic mimicry]

Anti-angiogenic drugs are used as an established approach of malignant neoplasms therapy. It has been established that the development of the phenomenon of vasculogenic mimicry - a specific variant of tumor neoangiogenesis, which is formed in highly aggressive solid tumors, is associated with a decrease in the effectiveness of antitumor therapy. This review highlights the mechanisms of development of vasculogenic mimicry in malignant neoplasms, which is one of the alternative options for tumor blood supply. In the formation of vasculogenic mimicry, an important role is assigned to the tumor microenvironment, primarily tumor-associated macrophages and fibroblasts. The signaling pathways that regulate the formation of vasculogenic mimicry channels in tumors have been characterized. The prospects for a targeted impact on molecular targets that initiate and promote vasculogenic mimicry, the impact on which can increase the effectiveness of antitumor therapy, are shown. The review discusses experimental studies of the mechanisms of vasculogenic mimicry formation in malignant neoplasms and the prospects for targeted action on molecules that are components of signaling cascades involved in the development of this model of neoangiogenesis.

Role of Exosomal Non-Coding RNA in the Tumour Microenvironment of Genitourinary System Tumours

In recent years, genitourinary system tumors are common in people of all ages, seriously affecting the quality of life of patients, the pathogenesis and treatment of these diseases are constantly being updated and improved. Exosomes, with a lipid bilayer that enable delivery of their contents into body fluids or other cells. Exosomes can regulate the tumor microenvironment, and play an important role in tumor development. In turn, cellular and non-cellular components of tumor microenvironment also affect the occurrence, progression, invasion and metastasis of tumor. Non-coding RNAs have been shown to be able to be ingested and released by exosomes, and are seen as a potential tool in cancer diagnosis and treatment. Here, we summarize the effect of non-coding RNAs of exosome contents on the tumor microenvironment of genitourinary system tumor, expound the significance of non-coding RNAs of exosome in the occurrence, development, diagnosis and treatment of cancers.

Macrophage - tumor cell interaction beyond cytokines

Tumor cells communication with tumor associated macrophages is a highly important factor of tumor malignant potential development. For a long time, studies of this interaction were focused on a cytokine- and other soluble factors -mediated processes. Discovery of exosomes and regulatory RNAs as their cargo opened a broad field of research. Non-coding RNAs (ncRNAs) were demonstrated to contribute significantly to the development of macrophage phenotype, not only by regulating expression of certain genes, but also by providing for feedback loops of macrophage activation. Being a usual cargo of macrophage- or tumor cell-derived exosomes ncRNAs provide an important mechanism of tumor-stromal cell interaction that contributes significantly to the pathogenesis of various types of tumors. Despite the volume of ongoing research there are still many gaps that must be filled before the practical use of ncRNAs will be possible. In this review we discuss the role of regulatory RNAs in the development of macrophage phenotype. Further we review recent studies supporting the hypothesis that macrophages may affect the properties of tumor cells and vice versa tumor cells influence macrophage phenotype by miRNA and lncRNA transported between these cells by exosomes. We suggest that this mechanism of tumor cell - macrophage interaction is highly promising for the development of novel diagnostic and therapeutic strategies, though many problems are still to be solved.

The Educational Program of Macrophages toward a Hyperprogressive Disease-Related Phenotype Is Orchestrated by Tumor-Derived Extracellular Vesicles

Hyperprogressive disease (HPD), an aggressive acceleration of tumor growth, was observed in a group of cancer patients treated with anti-PD1/PDL1 antibodies. The presence of a peculiar macrophage subset in the tumor microenvironment is reported to be a sort of "immunological prerequisite" for HPD development. These macrophages possess a unique phenotype that it is not clear how they acquire. We hypothesized that certain malignant cells may promote the induction of an "HPD-related" phenotype in macrophages. Bone-marrow-derived macrophages were exposed to the conditioned medium of five non-small cell lung cancer cell lines. Macrophage phenotype was analyzed by microarray gene expression profile and real-time PCR. We found that human NSCLC cell lines, reported as undergoing HPD-like tumor growth in immunodeficient mice, polarized macrophages towards a peculiar pro-inflammatory phenotype sharing both M1 and M2 features. Lipid-based factors contained in cancer cell-conditioned medium induced the over-expression of several pro-inflammatory cytokines and the activation of innate immune receptor signaling pathways. We also determined that tumor-derived Extracellular Vesicles represent the main components involved in the observed macrophage re-education program. The present study might represent the starting point for the future development of diagnostic tools to identify potential hyperprogressors.

Exosomal microRNA-1 and MYO15A as a target for therapy and diagnosis in renal cell carcinoma

Exosomes are 40-100 nm nano-sized extracellular vesicles and are receiving increasing attention as novel structures that participate in intracellular communication. We previously found that miRNA-1 (miR-1) functions as a tumor suppressor in renal cell carcinoma (RCC). In this study, we investigated the function of exosomal miR-1 and the possibility that the exosome constitutes a tumor maker in RCC. First, we established the method to collect exosomes from cell lysates and human serum by a spin column-based method. Next, we assessed exosomes using Nanosight nanoparticle tracking analysis and Western blot analysis with exosome marker CD63. We confirmed that exosomes labeled with PKH26 fused with recipient cells. Moreover, miR-1 expression was elevated in RCC cells treated with exosomes derived from miR-1-transfected cells. Functional analyses showed that exosomal miR-1 significantly inhibited cell proliferation, migration and invasion compared to control treatment. Our analyses with TCGA database of RCCs showed that miR-1 expression was significantly downregulated in clinical RCC samples compared to that in normal kidney samples, and patients with low miR-1 expression had poorer overall survival in comparison to patients with high expression. Furthermore, RNA sequence analyses showed that expression levels of several genes were altered by exposure to exosomal miR-1. The analyses with TCGA database indicated that high expression of MYO15A was associated with a poorer outcome in RCC. In addition, RT-qPCR analysis of exosomes from clinical patients' sera showed that MYO15A was significantly upregulated in RCC patients compared to that in healthy controls. This study showed that treatment with exosomal miR-1 might be an effective approach to treating RCCs. In addition, exosomal MYO15A could be a diagnostic tumor marker in RCCs.