Current status of research on exosomes in general, and for the diagnosis and treatment of kidney cancer in particular

Synthesis, Characterization, and Cytotoxicity Evaluation of Novel Water-Soluble Cationic Platinum(II) Organometallic Complexes with Phenanthroline and Imidazolic Ligands

Platinum-based chemotherapeutic agents are widely used in the treatment of cancer. However, their effectiveness is limited by severe adverse reactions, drug resistance, and poor water solubility. This study focuses on the synthesis and characterization of new water-soluble cationic monofunctional platinum(II) complexes starting from the [PtCl(η1-C2H4OEt)(phen)] (1, phen=1,10-phenanthroline) precursor, specifically [Pt(NH3)(η1-C2H4OEt)(phen)]Cl (2), [Pt(1-hexyl-1H-imidazole)(η1-C2H4OEt)(phen)]Cl (3), and [Pt(1-hexyl-1H-benzo[d]imidazole)(η1-C2H4OEt)(phen)]Cl (4), which deviate from traditional requirements for antitumor activity. These complexes were evaluated for their cytotoxic effects in comparison to cisplatin, using immortalized cervical adenocarcinoma cells (HeLa), human renal carcinoma cells (Caki-1), and normal human renal cells (HK-2). While complex 2 showed minimal effects on the cell lines, complexes 3 and 4 demonstrated higher cytotoxicity than cisplatin. Notably, complex 4 displayed the highest cytotoxicity in both cancer and normal cell lines. However, complex 3 exhibited the highest selectivity for renal tumor cells (Caki-1) among the tested complexes, compared to healthy cells (HK-2). This resulted in a significantly higher selectivity than that of cisplatin and complex 4. Therefore, complex 3 shows potential as a leading candidate for the development of a new generation of platinum-based anticancer drugs, utilizing biocompatible imidazole ligands while demonstrating promising anticancer properties.

Exosomes as novel tools for renal cell carcinoma therapy, diagnosis, and prognosis

Background

Renal Cell Carcinoma (RCC) stands as a formidable challenge within the field of oncology, despite considerable research endeavors. The advanced stages of this malignancy present formidable barriers to effective treatment and management.

Objective

This review aims to explore the potential of exosomes in addressing the diagnostic and therapeutic challenges associated with RCC. Specifically, it investigates the role of exosomes as biomarkers and therapeutic vehicles in the context of RCC management.

Methods

For this review article, a comprehensive literature search was conducted using databases such as PubMed, employing relevant keywords to identify research articles pertinent to the objectives of the review. Initially, 200 articles were identified, which underwent screening to remove duplicates and assess relevance based on titles and abstracts, followed by a detailed examination of full texts. From the selected articles, relevant data were extracted and synthesized to address the review's objectives. The conclusions were drawn based on a thorough analysis of the findings. The quality was ensured through independent review and resolution of discrepancies among multiple reviewers.

Results

Exosomes demonstrate potential as diagnostic tools for early detection, prognosis, and treatment monitoring in RCC. Their ability to deliver various therapeutic agents, such as small interfering RNAs, lncRNAs, chemotherapeutic drugs, and immune-stimulating agents, allows for a personalized approach to RCC management. By leveraging exosome-based technologies, precision and efficacy in treatment strategies can be significantly enhanced.

Conclusion

Despite the promising advancements enabled by exosomes in the management of RCC, further research is necessary to refine exosome-based technologies and validate their efficacy, safety, and long-term benefits through rigorous clinical trials. Embracing exosomes as integral components of RCC diagnosis and treatment represents a significant step towards improving patient outcomes and addressing the persistent challenges posed by this malignancy in the field of oncology.

SYT4 binds to SNAP25 to facilitate exosomal secretion and prostate cancer enzalutamide resistance

Prostate carcinoma represents a predominant malignancy affecting the male population, with androgen deprivation therapy (ADT) serving as a critical therapeutic modality for advanced disease states, but it often leads to the development of resistance. Enzalutamide (Enz), a second-generation antiandrogen drug, initially offers substantial therapeutic benefit, but its efficacy wanes as drug resistance ensues. In this study, we found that synaptotagmin 4 (SYT4) is an upregulated gene in enzalutamide-resistant (EnzR) cell lines. The downregulation of SYT4, in combination with enzalutamide therapy, substantially enhances the antiproliferative effect on resistant prostate cancer cells beyond the capacity of enzalutamide monotherapy. SYT4 promotes vesicle efflux by binding to the synaptosome-associated protein 25 (SNAP25), thereby contributing to cell resistance against enzalutamide. The elevated expression of SYT4 is mediated by bromodomain-containing protein 4 (BRD4), and BRD4 inhibition effectively suppressed the expression of SYT4. Treatment with a therapeutic dose of enzalutamide combined with ASO-1, an antisense oligonucleotide drug targeting SYT4, shows promising results in reversing the resistance of prostate cancer to enzalutamide.

Tissue-derived extracellular vesicles in cancer progression: mechanisms, roles, and potential applications

Extracellular vesicles (EVs) are small lipid bilayer-enclosed vesicles that mediate vital cellular communication by transferring cargo between cells. Among these, tissue-derived extracellular vesicles (Ti-EVs) stand out due to their origin from the tissue microenvironment, providing a more accurate reflection of changes in this setting. This unique advantage makes Ti-EVs valuable in investigating the intricate relationship between extracellular vesicles and cancer progression. Despite considerable research efforts exploring the association between Ti-EVs and cancers, a comprehensive clustering or grouping of these studies remains lacking. In this review, we aim to fill this gap by presenting a comprehensive synthesis of the mechanisms underlying Ti-EV generation, release, and transport within cancer tissues. Moreover, we delve into the pivotal roles that Ti-EVs play in cancer progression, shedding light on their potential as diagnostic and therapeutic tools. The review culminates in the construction of a comprehensive functional spectrum of Ti-EVs, providing a valuable reference for future research endeavors. By summarizing the current state of knowledge on Ti-EVs and their significance in tumor biology, this work contributes to a deeper understanding of cancer microenvironment dynamics and opens up avenues for harnessing Ti-EVs in diagnostic and therapeutic applications.

Shedding light on function of long non-coding RNAs (lncRNAs) in glioblastoma

The brain tumors and especially glioblastoma, are affecting life of many people worldwide and due to their high mortality and morbidity, their treatment is of importance and has gained attention in recent years. The abnormal expression of genes is commonly observed in GBM and long non-coding RNAs (lncRNAs) have demonstrated dysregulation in this tumor. LncRNAs have length more than 200 nucleotides and they have been located in cytoplasm and nucleus. The current review focuses on the role of lncRNAs in GBM. There two types of lncRNAs in GBM including tumor-promoting and tumor-suppressor lncRNAs and overexpression of oncogenic lncRNAs increases progression of GBM. LncRNAs can regulate proliferation, cell cycle arrest and metastasis of GBM cells. Wnt, STAT3 and EZH2 are among the molecular pathways affected by lncRNAs in GBM and for regulating metastasis of GBM cells, these RNA molecules mainly affect EMT mechanism. LncRNAs are involved in drug resistance and can induce resistance of GBM cells to temozolomide chemotherapy. Furthermore, lncRNAs stimulate radio-resistance in GBM cells. LncRNAs increase PD-1 expression to mediate immune evasion. LncRNAs can be considered as diagnostic and prognostic tools in GBM and researchers have developed signature from lncRNAs in GBM.

Bladder Cancer in Exosomal Perspective: Unraveling New Regulatory Mechanisms

Bladder cancer, a prevalent malignant neoplasm of the urinary tract, exhibits escalating morbidity and mortality rates. Current diagnosis standards rely on invasive and costly cystoscopy and histopathology, underscoring the urgency for non-invasive, high-throughput, and cost-effective novel diagnostic techniques to ensure timely detection and standardized treatment. Recent years have witnessed the rise of exosome research in bladder cancer studies. Exosomes contain abundant bioactive molecules that can help elucidate the intricate mechanisms underlying bladder cancer pathogenesis and metastasis. Exosomes hold potential as biomarkers for early bladder cancer diagnosis while also serving as targeted drug delivery vehicles to enhance treatment efficacy and mitigate adverse effects. Furthermore, exosome analyses offer insights into the complex molecular signaling networks implicated in bladder cancer progression, revealing novel therapeutic targets. This review provides a comprehensive overview of prevalent exosome isolation techniques and highlights the promising clinical utility of exosomes in both diagnostic and therapeutic applications in bladder cancer management.

Interaction of immune cells with renal cancer development: Mendelian randomization (MR) study

BACKGROUND

Renal cell carcinoma (RCC) is a prevalent and extensively immune-infiltrated malignancy of the urinary system. Immune cells play a crucial role in both the progression and therapeutic interventions targeting RCC. Nevertheless, the interplay between RCC and immune cells remains understudied, lacking substantial evidence supporting their causal relationship.

METHODS

For the purpose of investigating the causal connection between RCC and immune cell characteristics, a two-way two-sample Mendelian randomization (MR) analysis was carried out in this study. The aim was to determine whether specific immune cell traits have a causal impact on the risk of RCC. In order to achieve this, publicly accessible genetic data was utilized to examine and establish the potential relationship between 731 immune cell characteristics and the likelihood of developing RCC. Additionally, various techniques were applied to verify the reliability, variability, and presence of horizontal pleiotropy in the outcomes.

RESULTS

We found a bidirectional causal relationship between RCC and immune cells according to the MR analysis results. It should be noted that CD4-CD8-T cells (OR = 1.61, 95%CI = 1.02-2.55, P = 4.07 × 10-2) pose a risk for RCC, whereas BAFF-R (OR = 0.69, 95%CI = 0.53-0.89, P = 5.74 × 10-3) and CD19 (OR = 0.59, 95%CI = 1.02-2.55, P = 4.07 × 10-2) on B cells act as protective factors. Furthermore, the presence of RCC reduces the levels of B cells (OR = 1.05, 95%CI = 1.01-1.09, P = 1.19 × 10-2) and CD8 + T cells (OR = 1.04, 95%CI = 1.00-1.08, P = 2.83 × 10-2).

CONCLUSIONS

Our research illustrates the intricate correlation between immune cells and RCC, presenting novel insights for the prospective safeguarding against RCC risk and the exploration of fresh therapeutic targets.

Exosome-derived tRNA fragments tRF-GluCTC-0005 promotes pancreatic cancer liver metastasis by activating hepatic stellate cells

Early metastasis is the primary factor in the very poor prognosis of pancreatic ductal adenocarcinoma (PDAC), with liver metastasis being the most common form of distant metastasis in PDAC. To investigate the mechanism of PDAC liver metastasis, we found that PDAC cells can promote the formation of pre-metastatic niches (PMNs) through exosomes to facilitate liver metastasis in the early stage. In our study, hepatic stellate cells (HSCs) were treated with PDAC-derived exosomes (PDAC-exo), and the activation of HSCs was detected. A novel transfer RNA-derived fragment, the tRF-GluCTC-0005 was obtained by small RNA sequencing from serum exosomes of PDAC patients. Bioinformatics analysis and RNA pull-down assays revealed the interaction between WDR1 and tRF-GluCTC-0005. A KPC transgenic mouse model and an AAV-mediated sh-WDR1 mouse model were used to detect the mechanism of liver metastasis in vivo. Finally, the dual luciferase reporter assay, protein mutation truncation assay, Co-IP assay, and flow cytometry assay were used to explore the molecular mechanism in HSCs activation and PMNs formation. We found that the tRF-GluCTC-0005 in exosomes binds to the 3' untranslated region of the mRNA of the WDRl in HSCs and increases mRNA stability. The N-terminals of WDR1 bind to the YAP protein directly, inhibit YAP phosphorylation, and promote the expression of YAP transcription factors. The tRF-GluCTC-0005 in PDAC-exo significantly recruits myeloid-derived suppressor cells (MDSCs) in the liver, creating a PMNs immunosuppressive microenvironment and further advancing liver metastasis from PDAC. Our results suggest that the key of PDAC liver metastasis is the activation of HSCs through upregulation of WDR1 by tRF-GluCTC-0005 in exosomes, which mediates the infiltration of MDSCs to form PMNs.

Exosome-mediated regulation of inflammatory pathway during respiratory viral disease

Viruses have developed many mechanisms by which they can stimulate or inhibit inflammation and cause various diseases, including viral respiratory diseases that kill many people every year. One of the mechanisms that viruses use to induce or inhibit inflammation is exosomes. Exosomes are small membrane nanovesicles (30-150 nm) released from cells that contain proteins, DNA, and coding and non-coding RNA species. They are a group of extracellular vesicles that cells can take up to produce and mediate communication. Intercellular effect exosomes can deliver a broad confine of biological molecules, containing nucleic acids, proteins, and lipids, to the target cell, where they can convey therapeutic or pathogenic consequences through the modulation of inflammation and immune processes. Recent research has shown that exosomes can deliver entire virus genomes or virions to distant target cells, then the delivered viruses can escape the immune system and infect cells. Adenoviruses, orthomyxoviruses, paramyxoviruses, respiratory syncytial viruses, picornaviruses, coronaviruses, and rhinoviruses are mostly related to respiratory diseases. In this article, we will first discuss the current knowledge of exosomes. We will learn about the relationship between exosomes and viral infections, and We mention the inflammations caused by viruses in the airways, the role of exosomes in them, and finally, we examine the relationship between the viruses as mentioned earlier, and the regulation of inflammatory pathways that play a role in causing the disease.

Abnormal expression of FOXM1 in carcinogenesis of renal cell carcinoma: From experimental findings to clinical applications

Renal cell carcinoma (RCC) is a prevalent malignancy within the genitourinary system. At present, patients with high-grade or advanced RCC continue to have a bleak prognosis. Mounting research have emphasized the significant involvement of Forkhead box M1 (FOXM1) in RCC development and progression. Therefore, it is imperative to consolidate the existing evidence regarding the contributions of FOXM1 to RCC tumorigenesis through a comprehensive review. This study elucidated the essential functions of FOXM1 in promoting RCC growth, invasion, and metastasis by regulating cell cycle progression, DNA repair, angiogenesis, and epithelial-mesenchymal transition (EMT). Also, FOXM1 might serve as a novel diagnostic and prognostic biomarker as well as a therapeutic target for RCC. Clinical findings demonstrated that the expression of FOXM1 was markedly upregulated in RCC samples, while a high level of FOXM1 was found to be associated with a poor overall survival rate of RCC. Furthermore, it is worth noting that FOXM1 may have a significant impact on the resistance of renal cell carcinoma (RCC) to radiotherapy. This observation suggests that inhibiting FOXM1 could be a promising strategy to impede the progression of RCC and enhance its sensitivity to radiotherapy. The present review highlighted the pivotal role of FOXM1 in RCC development. FOXM1 has the capacity to emerge as not only a valuable diagnostic and prognostic tool but also a viable therapeutic option for unresectable RCC.

A specific technique of immunolabelling of urinary small extracellular vesicle biomarkers for the diagnostic of renal cancer

Small extracellular vesicles (EVs) are characterized by the membrane expression of CD63, CD81 and CD9 tetraspanins. Their size is inferior to 200 nm. They share the same characteristics as the native cells and are found in human fluids. Specific membrane protein biomarkers expressed on small EV are useful for the diagnosis of tumoural pathologies. Clear cell renal cell carcinoma (CCRCC) is diagnosed by imaging examinations and/or tissue biopsy. Carbonic anhydrase IX (CAIX) is a powerful biomarker of CCRCC. The detection of CAIX on small EV from the urine of patients could constitute a liquid biopsy for CCRCC. We have set up a specific protocol for the preparation, the immunostaining characterization and the transmission electron microscopy observation of small EVs isolated from the urine of CCRCC patients. The background labelling was significantly reduced. We successfully detected biomarkers on urinary small EVs from CCRCC patients. This technique could be extended with antibodies directed against other EV biomarkers for the detection and the monitoring of cancer diseases.

Extracellular vesicles in gastric cancer: role of exosomal lncRNA and microRNA as diagnostic and therapeutic targets

Extracellular vesicles (EVs), including exosomes, play a crucial role in intercellular communication and have emerged as important mediators in the development and progression of gastric cancer. This review discusses the current understanding of the role of EVs, particularly exosomal lncRNA and microRNA, in gastric cancer and their potential as diagnostic and therapeutic targets. Exosomes are small membrane-bound particles secreted by both cancer cells and stromal cells within the tumor microenvironment. They contain various ncRNA and biomolecules, which can be transferred to recipient cells to promote tumor growth and metastasis. In this review, we highlighted the importance of exosomal lncRNA and microRNA in gastric cancer. Exosomal lncRNAs have been shown to regulate gene expression by interacting with transcription factors or chromatin-modifying enzymes, which regulate gene expression by binding to target mRNAs. We also discuss the potential use of exosomal lncRNAs and microRNAs as diagnostic biomarkers for gastric cancer. Exosomes can be isolated from various bodily fluids, including blood, urine, and saliva. They contain specific molecules that reflect the molecular characteristics of the tumor, making them promising candidates for non-invasive diagnostic tests. Finally, the potential of targeting exosomal lncRNAs and microRNAs as a therapeutic strategy for gastric cancer were reviewed as wee. Inhibition of specific molecules within exosomes has been shown to suppress tumor growth and metastasis in preclinical models. In conclusion, this review article provides an overview of the current understanding of the role of exosomal lncRNA and microRNA in gastric cancer. We suggest that further research into these molecules could lead to new diagnostic tools and therapeutic strategies for this deadly disease.

Progress of regulatory RNA in small extracellular vesicles in colorectal cancer

Colorectal cancer (CRC) is the second most common malignant tumor of the gastrointestinal tract with the second highest mortality rate and the third highest incidence rate. Early diagnosis and treatment are important measures to reduce CRC mortality. Small extracellular vesicles (sEVs) have emerged as key mediators that facilitate communication between tumor cells and various other cells, playing a significant role in the growth, invasion, and metastasis of cancer cells. Regulatory RNAs have been identified as potential biomarkers for early diagnosis and prognosis of CRC, serving as crucial factors in promoting CRC cell proliferation, invasion and metastasis, angiogenesis, drug resistance, and immune cell differentiation. This review provides a comprehensive summary of the vital role of sEVs as biomarkers in CRC diagnosis and their potential application in CRC treatment, highlighting their importance as a promising avenue for further research and clinical translation.

Serum extracellular vesicles derived hsa-miR-320d as an indicator for progression of clear cell renal cell carcinoma

BACKGROUND

Renal cell carcinoma (RCC) is a prevalent malignancy with a rising incidence in developing countries. Clear cell renal cell carcinoma (ccRCC) constitutes 70% of RCC cases and is prone to metastasis and recurrence, yet lacks a liquid biomarker for surveillance. Extracellular vesicles (EVs) have shown promise as biomarkers in various malignancies. In this study, we investigated the potential of serum EV-derived miRNAs as a biomarker for ccRCC metastasis and recurrence.

MATERIALS AND METHODS

Patients diagnosed with ccRCC between 2017 and 2020 were recruited in this study. In the discovery phase, high throughput small RNA sequencing was used to analyze RNA extracted from serum EVs derived from localized ccRCC (LccRCC) and advanced ccRCC (AccRCC). In the validation phase, qPCR was employed for quantitative detection of candidate biomarkers. Migration and invasion assays were performed on ccRCC cell line OSRC2.

RESULTS

Serum EVs derived hsa-miR-320d was significantly up-regulated in patients with AccRCC than in patients with LccRCC (p < 0.01). In addition, Serum EVs derived hsa-miR-320d was also significantly up-regulated in patients who experienced recurrence or metastasis (p < 0.01). Besides, hsa-miR-320d enhances the pro-metastatic phenotype of ccRCC cells in vitro.

CONCLUSIONS

Serum EVs derived hsa-miR-320d as a liquid biomarker exhibits significant potential for identifying the recurrence or metastasis of ccRCC, as well as hsa-miR-320d promotes ccRCC cells migration and invasion.

Physiological and pathological consequences of exosomes at the blood-brain-barrier interface

Blood-brain barrier (BBB) interface with multicellular structure controls strictly the entry of varied circulating macromolecules from the blood-facing surface into the brain parenchyma. Under several pathological conditions within the central nervous system, the integrity of the BBB interface is disrupted due to the abnormal crosstalk between the cellular constituents and the recruitment of inflammatory cells. Exosomes (Exos) are nano-sized extracellular vesicles with diverse therapeutic outcomes. These particles transfer a plethora of signaling molecules with the potential to modulate target cell behavior in a paracrine manner. Here, in the current review article, the therapeutic properties of Exos and their potential in the alleviation of compromised BBB structure were discussed. Video Abstract.

ALDOC- and ENO2- driven glucose metabolism sustains 3D tumor spheroids growth regardless of nutrient environmental conditions: a multi-omics analysis

BACKGROUND

Metastases are the major cause of cancer-related morbidity and mortality. By the time cancer cells detach from their primary site to eventually spread to distant sites, they need to acquire the ability to survive in non-adherent conditions and to proliferate within a new microenvironment in spite of stressing conditions that may severely constrain the metastatic process. In this study, we gained insight into the molecular mechanisms allowing cancer cells to survive and proliferate in an anchorage-independent manner, regardless of both tumor-intrinsic variables and nutrient culture conditions.

METHODS

3D spheroids derived from lung adenocarcinoma (LUAD) and breast cancer cells were cultured in either nutrient-rich or -restricted culture conditions. A multi-omics approach, including transcriptomics, proteomics, and metabolomics, was used to explore the molecular changes underlying the transition from 2 to 3D cultures. Small interfering RNA-mediated loss of function assays were used to validate the role of the identified differentially expressed genes and proteins in H460 and HCC827 LUAD as well as in MCF7 and T47D breast cancer cell lines.

RESULTS

We found that the transition from 2 to 3D cultures of H460 and MCF7 cells is associated with significant changes in the expression of genes and proteins involved in metabolic reprogramming. In particular, we observed that 3D tumor spheroid growth implies the overexpression of ALDOC and ENO2 glycolytic enzymes concomitant with the enhanced consumption of glucose and fructose and the enhanced production of lactate. Transfection with siRNA against both ALDOC and ENO2 determined a significant reduction in lactate production, viability and size of 3D tumor spheroids produced by H460, HCC827, MCF7, and T47D cell lines.

CONCLUSIONS

Our results show that anchorage-independent survival and growth of cancer cells are supported by changes in genes and proteins that drive glucose metabolism towards an enhanced lactate production. Notably, this finding is valid for all lung and breast cancer cell lines we have analyzed in different nutrient environmental conditions. broader Validation of this mechanism in other cancer cells of different origin will be necessary to broaden the role of ALDOC and ENO2 to other tumor types. Future in vivo studies will be necessary to assess the role of ALDOC and ENO2 in cancer metastasis.

Exosomal circular RNAs: A chief culprit in cancer chemotherapy resistance

Chemotherapy is one of the primary treatments for malignant tumors. However, the acquired drug resistance hinders clinical efficacy and leads to treatment failure in most patients. Exosomes are cell-derived vesicles with a diameter of 30-150 nm carrying and delivering substances such as DNAs, RNAs, lipids, and proteins for cellular communication in tumor development. Circular RNAs (circRNAs) present covalently closed-loop RNA structures, which regulate tumor cell proliferation, apoptosis, and metastasis by controlling different genes and signaling pathways. CircRNAs are abundant and stably expressed in exosomes. Recent studies have shown that they play critical roles in chemotherapy resistance in various cancers. In this review, we summarized the origin of exosomes and discussed the regulation mechanism of exosomal circRNAs in cancer drug resistance.

Exosomes: A potential tool for immunotherapy of ovarian cancer

Ovarian cancer is a malignant tumor of the female reproductive system, with a very poor prognosis and high mortality rates. Chemotherapy and radiotherapy are the most common treatments for ovarian cancer, with unsatisfactory results. Exosomes are a subpopulation of extracellular vesicles, which have a diameter of approximately 30-100 nm and are secreted by many different types of cells in various body fluids. Exosomes are highly stable and are effective carriers of immunotherapeutic drugs. Recent studies have shown that exosomes are involved in various cellular responses in the tumor microenvironment, influencing the development and therapeutic efficacy of ovarian cancer, and exhibiting dual roles in inhibiting and promoting tumor development. Exosomes also contain a variety of genes related to ovarian cancer immunotherapy that could be potential biomarkers for ovarian cancer diagnosis and prognosis. Undoubtedly, exosomes have great therapeutic potential in the field of ovarian cancer immunotherapy. However, translation of this idea to the clinic has not occurred. Therefore, it is important to understand how exosomes could be used in ovarian cancer immunotherapy to regulate tumor progression. In this review, we summarize the biomarkers of exosomes in different body fluids related to immunotherapy in ovarian cancer and the potential mechanisms by which exosomes influence immunotherapeutic response. We also discuss the prospects for clinical application of exosome-based immunotherapy in ovarian cancer.

Role of exosomes in tumour growth, chemoresistance and immunity: state-of-the-art

Cancer is one of the most lethal diseases, and limited available treatment options contribute to its high mortality rate. Exosomes are considered membrane-bound nanovesicles that include different molecules such as lipids, proteins, and nucleic acids. Virtually most cells could release exosomes via exocytosis in physiological and pathological conditions. Tumour-derived exosomes (TDEs) play essential roles in tumorigenesis, proliferation, progression, metastasis, immune escape, and chemoresistance by transferring functional biological cargos, triggering different autocrine, and paracrine signalling cascades. Due to their antigen-presenting properties, exosomes are widely used as biomarkers and drug carriers and have a prominent role in cancer immunotherapy. They offer various advantages in carrier systems (e.g. in chemotherapy, siRNA, and miRNA), delivery of diagnostic agents owing to their stability, loading of hydrophobic and hydrophilic agents, and drug targeting. Novel exosomes-based carriers can be generated as intelligent systems using various sources and crosslinking chemistry extracellular vesicles (EVs). Exosomes studded with targeting ligands, including peptides, can impart in targeted delivery of cargos to tumour cells. In this review, we comprehensively summarised the important role of tumour-derived exosomes in dictating cancer pathogenesis and resistance to therapy. We have therefore, investigated in further detail the pivotal role of tumour-derived exosomes in targeting various cancer cells and their applications, and prospects in cancer therapy and diagnosis. Additionally, we have implicated the potential utility and significance of tumour exosomes-based nanoparticles as an efficient and novel therapeutic carrier and their applications in treating advanced cancers.

Role of tumor-derived exosomes in metastasis, drug resistance and diagnosis of clear cell renal cell carcinoma

Renal cancer is one of the most extensively studied human tumors today, with clear cell renal cell carcinoma accounting for approximately 80% of all cases. Despite recent advances in research on clear cell renal cell carcinoma, advanced distant metastasis of the disease, delay in diagnosis, as well as drug resistance remain major problems. In recent years, as an important mediator of material and information exchange between cells in the tumor microenvironment, exosomes have attracted widespread attention for their role in tumor development. It has been reported that tumor-derived exosomes may act as regulators and have an important effect on the metastasis, drug resistance formation, and providing targets for early diagnosis of clear cell renal cell carcinoma. Therefore, the extensive study of tumour-derived exosomes will provide a meaningful reference for the development of the diagnostic and therapeutic field of clear cell renal cell carcinoma. This article reviews the biological role and research progress of tumor-derived exosomes in different aspects of premetastatic niche formation, tumor angiogenesis, and epithelial-mesenchymal transition during the progression of clear cell renal cell carcinoma. In addition, the role of tumor-derived exosomes in the development of drug resistance in clear cell renal cell carcinoma is also addressed in this review. Furthermore, recent studies have found that cargoes of exosomes in serum and urine, for example, a series of miRNAs, have the potential to be biological markers of clear cell renal cell carcinoma and provide meaningful targets for early diagnosis and monitoring of tumors, which is also covered in this article.

Glycine Decarboxylase Suppresses the Renal Cell Carcinoma Growth and Regulates Its Gene Expressions and Functions

Background

Glycine decarboxylase (GLDC), a key metabolic enzyme, participates in the regulation of the glycine metabolic pathway. Differential expression of GLDC is linked to the malignant growth of renal cell carcinoma (RCC) and may regulate tumor progression through other genes. However, the regulatory function of GLDC in RCC is currently unknown. The purpose of this work was to evaluate the roles of GLDC in the invasion, proliferation, and migration of RCC cells and elucidate the processes underlying RCC development.

Methods

The expression of GLDC in RCC cell lines and tissues was identified by quantitative reverse transcription polymerase chain reaction (PCR) and western blot. A stably transfected cell line overexpressing GLDC was constructed using a lentiviral vector. Cell proliferation was detected using Cell Counting Kit-8 (CCK8) and EdU experiments, and scratch and transwell assays were used to determine migration and invasion capabilities. Furthermore, differential proteins were identified and obtained using high-performance liquid chromatography (HPLC)-tandem mass spectrometry (MS/MS) analysis. Finally, these differential proteins were analyzed by bioinformatics, including cluster analysis, subcellular localization, domain annotation, annotation of the Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG), enrichment analysis, and study of protein-protein interactions.

Results

GLDC expression was found to be lower in six RCC cell lines (786-O, A498, Caki-1, 769-P, OSRC-2, and ACHN) than in 293T cells and decreased in kidney cancer tissues compared to neighboring normal tissues. Overexpression of GLDC inhibited the proliferation of RCC cells as well as their migration and invasion abilities. Tandem mass tag analysis showed that 317 and 236 genes were downregulated and upregulated, respectively, when GLDC was overexpressed in A498 cells. Tandem mass tag analysis showed that 317 and 236 genes were downregulated and upregulated, respectively, when GLDC was overexpressed in A498 cells. Volcano plot showed these upregulated and downregulated proteins. Cluster analysis showed that differentially expressed protein screening can represent the effect of biological treatment on samples. Subcellular localization analysis showed differential proteins are mainly distributed in the nucleus, cytoplasm, mitochondria, plasma membrane, extracellular matrix, and lysosome. GO annotation showed many biological processes in the cells were changed, including "positive regulation of histone H3-K4 methylation", "cofactor binding", and "nuclear body". KEGG pathway analysis showed key pathways have all undergone considerable alterations, such as "cell cycle", "glyoxylate and dicarboxylate metabolism", and "threonine, glycine, and serine metabolism". Finally, highly aggregated proteins with the same or similar functions were acquired by analysis of the protein-protein interaction (PPI) network.

Conclusions

These studies indicate that GLDC overexpression suppresses the invasion, proliferation, and migration of RCC cells and leads to the upregulation and downregulation of 236 and 317 genes, respectively.

CASP4 and CASP8 as newly defined autophagy-pyroptosis-related genes associated with clinical and prognostic features of renal cell carcinoma

Objective

The rapid discoveries of autophagy and pyroptosis have opened new avenues for treating renal cell carcinoma (RCC). The objective was to identify potential autophagy-pyroptosis-related drug targets and plausible prognostic biomarkers crucial for disease detection.

Materials and Methods

Gene expression data were downloaded from Gene Expression Omnibus (GSE168845), and autophagy-pyroptosis-related differentially expressed genes (DEGs) were identified. The prognostic values of DEGs were assessed using differential expression analysis and Kaplan-Meier curves, a prognostic nomogram was constructed using the DEG data, and the correlation between DEGs and infiltrating immune cells was evaluated. Additionally, quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC) were carried out to verify the expression levels of DEGs.

Results

CASP4 and CASP8 were identified as RCC-associated autophagy-pyroptosis-related genes, and CASP4 and CASP8 were found to be highly expressed in RCC tumor tissues. High expression of CASP4 and CASP8 was associated with higher pathological staging and poorer prognosis, whereas a prognostic nomogram constructed based on CASP4 and CASP8 could better predict RCC patient survival rates. Additionally, increased expression of CASP4 and CASP8 was highly correlated with the expression levels of multiple infiltrating immune cell types. Moreover, qRT-PCR and IHC validated the increased expression of CASP4 and CASP8 in RCC.

Conclusion

CASP4 and CASP8 were autophagy-pyroptosis-related genes associated with immunotherapy in RCC. CASP4 and CASP8 were identified as potential targets and effective prognostic biomarkers for RCC.

Extracellular vesicles: A new diagnostic biomarker and targeted drug in osteosarcoma

Osteosarcoma (OS) is a primary bone cancer that is highly prevalent among adolescents and adults below the age of 20 years. The prognostic outcome of metastatic OS or relapse is extremely poor; thus, developing new diagnostic and therapeutic strategies for treating OS is necessary. Extracellular vesicles (EVs) ranging from 30–150 nm in diameter are commonly produced in different cells and are found in various types of body fluids. EVs are rich in biologically active components like proteins, lipids, and nucleic acids. They also strongly affect pathophysiological processes by modulating the intercellular signaling pathways and the exchange of biomolecules. Many studies have found that EVs influence the occurrence, development, and metastasis of osteosarcoma. The regulation of inflammatory communication pathways by EVs affects OS and other bone-related pathological conditions, such as osteoarthritis and rheumatoid arthritis. In this study, we reviewed the latest findings related to diagnosis, prognosis prediction, and the development of treatment strategies for OS from the perspective of EVs.

Mesenchymal Stem Cell-Derived Small Extracellular Vesicles: A Novel Approach for Kidney Disease Treatment

Globally, kidney disease has become a serious health challenge, with approximately 10% of adults suffering with the disease, and increasing incidence and mortality rates every year. Small extracellular vesicles (sEVs) are 30 nm-100 nm sized nanovesicles released by cells into the extracellular matrix (ECM), which serve as mediators of intercellular communication. Depending on the cell origin, sEVs have different roles which depend on internal cargoes including, nucleic acids, proteins, and lipids. Mesenchymal stem cell (MSCs) exert anti-inflammatory, anti-aging, and wound healing functions mainly via sEVs in a stable and safe manner. MSC-derived sEVs (MSC-sEVs) exert roles in several kidney diseases by transporting renoprotective cargoes to reduce oxidative stress, inhibit renal cell apoptosis, suppress inflammation, and mediate anti-fibrosis mechanisms. Additionally, because MSC-sEVs efficiently target damaged kidneys, they have the potential to become the next generation cell-free therapies for kidney disease. Herein, we review recent research data on how MSC-sEVs could be used to treat kidney disease.

Combination of preoperative plasma fibrinogen and neutrophil-to-lymphocyte ratio to predict the prognosis for patients undergoing laparoscopic nephrectomy for renal cell carcinoma

This study was conducted to investigate the prognostic significance of a combination of fibrinogen and neutrophil-to-lymphocyte ratio (NLR) named the F-NLR score as a novel indicator and further create nomograms for predicting the prognosis of patients with renal cell carcinoma (RCC) treated with laparoscopic nephrectomy. A total of 425 patients with RCC who underwent laparoscopic nephrectomy were included in this study. Then, we divided the patients based on the cut-off values of their F-NLR score into three categories: F-NLR 2 (both high fibrinogen and NLR), F-NLR 0 (both low fibrinogen and NLR), and F-NLR 1 (remaining patients). Cox regression analysis was performed to investigate the predictive performance of the F-NLR score on overall survival (OS) and cancer-specific survival (CSS). Predictive nomograms of F-NLR were established and internally validated. Time-dependent receiver operating characteristic (ROC) curve analysis was performed to assess the predictive accuracy of the nomogram, NLR, and fibrinogen as prognostic markers. The F-NLR 0, 1, and 2 groups included 226 (53.2%), 147 (34.6%), and 52 (12.2%) patients, respectively. Cox regression analysis showed that a high F-NLR score was significantly associated with poor prognosis and acted as an independent prognostic factor for OS and CSS (all P < 0.05). Predictive nomograms with F-NLR for OS (C-index: 0.773) and CSS (C-index: 0.838) were well developed. Time-dependent ROC results showed that nomograms containing F-NLR had better predictive performance than NLR and fibrinogen. F-NLR score was a novel effective prognostic biomarker for patients with RCC undergoing laparoscopic nephrectomy.

Stanniocalcin 2 (STC2): a universal tumour biomarker and a potential therapeutical target

Stanniocalcin 2 (STC2) is a glycoprotein which is expressed in a broad spectrum of tumour cells and tumour tissues derived from human breast, colorectum, stomach, esophagus, prostate, kidney, liver, bone, ovary, lung and so forth. The expression of STC2 is regulated at both transcriptional and post-transcriptional levels; particularly, STC2 is significantly stimulated under various stress conditions like ER stress, hypoxia and nutrient deprivation. Biologically, STC2 facilitates cells dealing with stress conditions and prevents apoptosis. Importantly, STC2 also promotes the development of acquired resistance to chemo- and radio- therapies. In addition, multiple groups have reported that STC2 overexpression promotes cell proliferation, migration and immune response. Therefore, the overexpression of STC2 is positively correlated with tumour growth, invasion, metastasis and patients' prognosis, highlighting its potential as a biomarker and a therapeutic target. This review focuses on discussing the regulation, biological functions and clinical importance of STC2 in human cancers. Future perspectives in this field will also be discussed.

Noncoding-RNA mediated high expression of zinc finger protein 268 suppresses clear cell renal cell carcinoma progression by promoting apoptosis and regulating immune cell infiltration

Clear cell renal cell carcinoma (ccRCC) is one of the most common malignant kidney tumors with a poor prognosis. Accumulating evidence proves that zinc finger protein 268 (ZNF268) is associated with tumor progression, but the detailed regulatory functions of ZNF268 in ccRCC require further exploration. Thus, here we aim to characterize the role of ZNF268 in ccRCC. The clinical significance of ZNF268 was evaluated using The Cancer Genome Atlas (TCGA) and the Genotype-Tissue Expression (GTEx) databases. Subsequently, tumor-infiltrating immune cells, as well as upstream noncoding RNAs (ncRNAs) related to the tumor-suppressing function of ZNF268, were identified by in silico analyses. The expression of ZNF268 was significantly decreased in ccRCC samples compared with adjacent normal tissues. In addition, ZNF268 expression was negatively correlated with tumor progression and positively correlated with overall and disease-specific survival. TCGA and GTEx databases proved the potential tumor-suppressing function, which was measured both in vitro and in vivo after ZNF268 over-expression. Overexpression of ZNF268 effectively inhibited the proliferation, migration, invasion and promotied apoptosis of the Caki-1. The level of ZNF268 was positively related to the immune cell infiltration in the tumor. Moreover, we determined that the AC093157.1/miR-27a-3p axis can potentially regulate ZNF268 function in ccRCC. Our work describes a novel ncRNA-mediated ZNF268 function in ccRCC. ZNF268 acts as a tumor suppressor, and it is associated with apoptosis and immune cell infiltration in ccRCC.

Exosomal Proteins and Lipids as Potential Biomarkers for Lung Cancer Diagnosis, Prognosis, and Treatment

Simple Summary

Exosomes (or extracellular vesicles) are known to mediate intercellular communication and to transmit molecular signals between cells. Molecules carried by exosomes have their own molecular roles in affecting surrounding and distant environment, as well as recipient cells. Molecular components of exosomes can be used as cancer biomarkers for diagnosis and prognosis, being promising therapeutic targets for the interruption of cellular signals. Therefore, the understanding of the molecular compositions and their functional indications of exosomes has the potential to help doctors to diagnose and monitor diseases and to allow researchers to design and develop potential targeted therapies. This review aims to provide a comprehensive protein and lipid characterization of lung cancer exosomes and to explore their molecular functions and mechanisms regulating physiological and pathological processes. This organization offers informative insight for lung cancer diagnosis and treatment.

Abstract

Exosomes participate in cell–cell communication by transferring molecular components between cells. Previous studies have shown that exosomal molecules derived from cancer cells and liquid biopsies can serve as biomarkers for cancer diagnosis and prognosis. The exploration of the molecules transferred by lung cancer-derived exosomes can advance the understanding of exosome-mediated signaling pathways and mechanisms. However, the molecular characterization and functional indications of exosomal proteins and lipids have not been comprehensively organized. This review thoroughly collected data concerning exosomal proteins and lipids from various lung cancer samples, including cancer cell lines and cancer patients. As potential diagnostic and prognostic biomarkers, exosomal proteins and lipids are available for clinical use in lung cancer. Potential therapeutic targets are mentioned for the future development of lung cancer therapy. Molecular functions implying their possible roles in exosome-mediated signaling are also discussed. Finally, we emphasized the importance and value of lung cancer stem cell-derived exosomes in lung cancer therapy. In summary, this review presents a comprehensive description of the protein and lipid composition and function of lung cancer-derived exosomes for lung cancer diagnosis, prognosis, and treatment.

Advances in the Application of Exosomes Identification Using Surface-Enhanced Raman Spectroscopy for the Early Detection of Cancers

Exosomes are small nanoscale vesicles with a double-layered lipid membrane structure secreted by cells, and almost all types of cells can secrete exosomes. Exosomes carry a variety of biologically active contents such as nucleic acids and proteins, and play an important role not only in intercellular information exchange and signal transduction, but also in various pathophysiological processes in the human body. Surface-enhanced Raman Spectroscopy (SERS) uses light to interact with nanostructured materials such as gold and silver to produce a strong surface plasmon resonance effect, which can significantly enhance the Raman signal of molecules adsorbed on the surface of nanostructures to obtain a rich fingerprint of the sample itself or Raman probe molecules with ultra-sensitivity. The unique advantages of SERS, such as non-invasive and high sensitivity, good selectivity, fast analysis speed, and low water interference, make it a promising technology for life science and clinical testing applications. In this paper, we briefly introduce exosomes and the current main detection methods. We also describe the basic principles of SERS and the progress of the application of unlabeled and labeled SERS in exosome detection. This paper also summarizes the value of SERS-based exosome assays for early tumor diagnosis.

Understanding the link between kidney stones and cancers of the upper urinary tract and bladder

Kidney stones are one of the most common renal pathologies. While emerging evidence has implicated a potential association between kidney stones and upper urinary tract cancers (including renal cancer), there is limited understanding as to the common underlying biological pathways functionally linking the etiology of kidney stone formation and the incidence, development, and progression of urinary tract cancers. From a clinical perspective, kidney stone disease can be a barrier to oncologic care due to renal obstruction. From the epidemiological perspective, risk factors associated with both conditions include smoking, alcohol consumption, diet, and gender. Herein, we review the association between renal calculi and malignancy of the upper urinary tract and discuss the current understanding of (a) potential shared mechanisms, and (b) the impact this has on shared therapeutic management of both conditions.