CML derived exosomes promote tumor favorable functional performance in T cells

Application of exosomes in tumor immunity: recent progresses

Exosomes are small extracellular vesicles secreted by cells, ranging in size from 30 to 150 nm. They contain proteins, nucleic acids, lipids, and other bioactive molecules, which play a crucial role in intercellular communication and material transfer. In tumor immunity, exosomes present various functions while the following two are of great importance: regulating the immune response and serving as delivery carriers. This review starts with the introduction of the formation, compositions, functions, isolation, characterization, and applications of exosomes, and subsequently discusses the current status of exosomes in tumor immunotherapy, and the recent applications of exosome-based tumor immunity regulation and antitumor drug delivery. Finally, current challenge and future prospects are proposed and hope to demonstrate inspiration for targeted readers in the field.

Extracellular vesicles in the Chronic Myeloid Leukemia scenario: an update about the shuttling of disease markers and therapeutic molecules

Extracellular vesicles (EVs) are various sets of cell-derived membranous structures containing lipids, nucleic acids, and proteins secreted by both eukaryotic and prokaryotic cells. It is now well recognized that EVs are key intercellular communication mediators, allowing the functional transfer of bioactive chemicals from one cell to another in both healthy and pathological pathways. It is evident that the condition of the producer cells heavily influences the composition of EVs. Hence, phenotypic changes in the parent cells are mirrored in the design of the secreted EVs. As a result, EVs have been investigated for a wide range of medicinal and diagnostic uses in different hematological diseases. EVs have only recently been studied in the context of Chronic Myeloid Leukemia (CML), a blood malignancy defined by the chromosomal rearrangement t(9;22) and the fusion gene BCR-ABL1. The findings range from the impact on pathogenesis to the possible use of EVs as medicinal chemical carriers. This review aims to provide for the first time an update on our understanding of EVs as carriers of CML biomarkers for minimal residual disease monitoring, therapy response, and its management, as well as the limited reports on the use of EVs as therapeutic shuttles for innovative treatment approaches.

Biological, pathological, and multifaceted therapeutic functions of exosomes to target cancer

Exosomes, small tiny vesicle contains a large number of intracellular particles that employ to cause various diseases and prevent several pathological events as well in the human body. It is considered a "double-edged sword", and depending on its biological source, the action of exosomes varies under physiological conditions. Also, the isolation and characterization of the exosomes should be performed accurately and the methodology also will vary depending on the exosome source. Moreover, the uptake of exosomes from the recipients' cells is a vital and initial step for all the physiological actions. There are different mechanisms present in the exosomes' cellular uptake to deliver their cargo to acceptor cells. Once the exosomal uptake takes place, it releases the intracellular particles that leads to activate the physiological response. Even though exosomes have lavish functions, there are some challenges associated with every step of their preparation to bring potential therapeutic efficacy. So, overcoming the pitfalls would give a desired quantity of exosomes with high purity.

Extracellular vesicles in hematological malignancies: EV-dence for reshaping the tumoral microenvironment

Following their discovery at the end of the 20th century, extracellular vesicles (EVs) ranging from 50-1,000 nm have proven to be paramount in the progression of many cancers, including hematological malignancies. EVs are a heterogeneous group of cell-derived membranous structures that include small EVs (commonly called exosomes) and large EVs (microparticles). They have been demonstrated to participate in multiple physiological and pathological processes by allowing exchange of biological material (including among others proteins, DNA and RNA) between cells. They are therefore a crucial way of intercellular communication. In this context, malignant cells can release these extracellular vesicles that can influence their microenvironment, induce the formation of a tumorigenic niche, and prepare and establish distant niches facilitating metastasis by significantly impacting the phenotypes of surrounding cells and turning them toward supportive roles. In addition, EVs are also able to manipulate the immune response and to establish an immunosuppressive microenvironment. This in turn allows for ideal conditions for heightened chemoresistance and increased disease burden. Here, we review the latest findings and reports studying the effects and therapeutic potential of extracellular vesicles in various hematological malignancies. The study of extracellular vesicles remains in its infancy; however, rapid advances in the analysis of these vesicles in the context of disease allow us to envision prospects to improve the detection and treatment of hematological malignancies.

The role of bone marrow microenvironment (BMM) cells in acute myeloid leukemia (AML) progression: immune checkpoints, metabolic checkpoints, and signaling pathways

Acute myeloid leukemia (AML) comprises a multifarious and heterogeneous array of illnesses characterized by the anomalous proliferation of myeloid cells in the bone marrow microenvironment (BMM). The BMM plays a pivotal role in promoting AML progression, angiogenesis, and metastasis. The immune checkpoints (ICs) and metabolic processes are the key players in this process. In this review, we delineate the metabolic and immune checkpoint characteristics of the AML BMM, with a focus on the roles of BMM cells e.g. tumor-associated macrophages, natural killer cells, dendritic cells, metabolic profiles and related signaling pathways. We also discuss the signaling pathways stimulated in AML cells by BMM factors that lead to AML progression. We then delve into the roles of immune checkpoints in AML angiogenesis, metastasis, and cell proliferation, including co-stimulatory and inhibitory ICs. Lastly, we discuss the potential therapeutic approaches and future directions for AML treatment, emphasizing the potential of targeting metabolic and immune checkpoints in AML BMM as prognostic and therapeutic targets. In conclusion, the modulation of these processes through the use of directed drugs opens up new promising avenues in combating AML. Thereby, a comprehensive elucidation of the significance of these AML BMM cells' metabolic and immune checkpoints and signaling pathways on leukemic cells can be undertaken in the future investigations. Additionally, these checkpoints and cells should be considered plausible multi-targeted therapies for AML in combination with other conventional treatments in AML. Video Abstract.

Profiling of miRNAs and their interfering targets in peripheral blood mononuclear cells from patients with chronic myeloid leukaemia

Introduction

MicroRNAs may be implicated in the acquisition of drug resistance in chronic myeloid leukemia as they regulate the expression of not only BCR-ABL1 but also genes associated with the activation of drug transfer proteins or essential signaling pathways.

Methods

To understand the impact of specifically expressed miRNAs in chronic myeloid leukemia and their target genes, we collected peripheral blood mononuclear cells (PBMC) from patients diagnosed with chronic myeloid leukemia (CML) and healthy donors to determine whole miRNA expression by small RNA sequencing and screened out 31 differentially expressed microRNAs (DE-miRNAs) with high expression. With the utilization of miRNA set enrichment analysis tools, we present here a comprehensive analysis of the relevance of DE-miRNAs to disease and biological function. Furthermore, the literature-based miRNA-target gene database was used to analyze the overall target genes of the DE-miRNAs and to define their associated biological responses. We further integrated DE-miRNA target genes to identify CML miRNA targeted gene signature singscore (CMTGSS) and used gene-set enrichment analysis (GSEA) to analyze the correlation between CMTGSS and Hallmark gene-sets in PBMC samples from clinical CML patients. Finally, the association of CMTGSS stratification with multiple CML cell lineage gene sets was validated in PBMC samples from CML patients using GSEA.

Results

Although individual miRNAs have been reported to have varying degrees of impact on CML, overall, our results show that abnormally upregulated miRNAs are associated with apoptosis and aberrantly downregulated miRNAs are associated with cell cycle. The clinical database shows that our defined DE-miRNAs are associated with the prognosis of CML patients. CMTGSS-based stratification analysis presented a tendency for miRNAs to affect cell differentiation in the blood microenvironment.

Conclusion

Collectively, this study defined differentially expressed miRNAs by miRNA sequencing from clinical samples and comprehensively analyzed the biological functions of the differential miRNAs in association with the target genes. The analysis of the enrichment of specific myeloid differentiated cells and immune cells also suggests the magnitude and potential targets of differentially expressed miRNAs in the clinical setting. It helps us to make links between the different results obtained from the multi-faceted studies to provide more potential research directions.

Oral squamous cell carcinoma-derived EVs promote tumor progression by regulating inflammatory cytokines and the IL-17A-induced signaling pathway

BACKGROUND

Inflammatory cytokines in the tumor microenvironment (TME) contribute to tumor growth, proliferation, and invasion, and tumor-derived extracellular vesicles (EVs) act as critical "messengers" of communication in the tumor microenvironment. The effects of EVs derived from oral squamous cell carcinoma (OSCC) cells on tumor progression and the inflammatory microenvironment are still unclear. Our study aims to investigate the role of OSCC-derived EVs in tumor progression, the imbalanced TME, and immunosuppression and their effect on the IL-17A-induced signaling pathway.

METHODS

EVs were isolated from the supernatant of a mouse OSCC cell line, SCC7. The effects of SCC7-EVs and the EV release-specific inhibitor GW4869 on the proliferation and migration of SCC7 cells were investigated in vitro by using CCK-8 and scratch wound healing assays. RT-qPCR and ELISA were performed to examine the alterations in cytokine levels. Then, a mouse xenograft model of OSCC was established by submucosal injection of SCC7 cells with or without SCC7-EV and GW4869 treatment. The effects of GW4869 and SCC7-EVs on xenograft tumor proliferation and invasion were investigated by tumor volume determination and histopathological examination. ELISA was used to investigate the changes in serum cytokine levels. Immunohistochemistry was adopted to analyze the alterations in the levels of inflammatory cytokines, immune factors, and crucial molecules in the IL-17A signaling pathway.

RESULTS

SCC7-derived EVs increased the supernatant and serum levels of IL-17A, IL-10, IL-1β, and PD-L1, while GW4869 decreased those of TNF-α and IFN-γ. SCC7-EV treatment significantly increased xenograft tumor growth and invasion in mice but resulted in little liquefactive necrosis in tumors. However, GW4869 treatment significantly inhibited xenograft tumor growth but resulted in more liquefactive necrosis. SCC7-derived EVs decreased the expression level of PTPN2, suppressing the immune responses of CD8 + T cells in vivo. Moreover, SCC7-EV treatment significantly enhanced the tumor expression levels of crucial molecules in the IL-17A pathway, including IL-17A, TRAF6 and c-FOS, whereas GW4869 treatment significantly reduced those levels in tumor tissues.

CONCLUSION

Our results indicated that OSCC-derived EVs can promote tumor progression by altering the TME, causing an inflammatory cytokine imbalance, inducing immunosuppression, and contributing to overactivation of the IL-17A-induced signaling pathway. Our study might provide novel insights into the role of OSCC-derived EVs in tumor biological behavior and immune dysregulation.

The Bone Marrow Immune Microenvironment in CML: Treatment Responses, Treatment-Free Remission, and Therapeutic Vulnerabilities

PURPOSE OF REVIEW

Tyrosine kinase inhibitors (TKIs) are very successful for the treatment of chronic myeloid leukaemia (CML) but are not curative in most patients due to persistence of TKI-resistant leukaemia stem cells (LSCs). The bone marrow immune microenvironment (BME) provides protection to the LSC through multidimensional interactions, driving therapy resistance, and highlighting the need to circumvent these protective niches therapeutically. This review updates the evidence for interactions between CML cells and the immune microenvironment with a view to identifying targetable therapeutic vulnerabilities and describes what is known about the role of immune regulation in treatment-free remission (TFR).

RECENT FINDINGS

Intracellular signalling downstream of the chemotactic CXCL12-CXCR4 axis, responsible for disrupted homing in CML, has been elucidated in LSCs, highlighting novel therapeutic opportunities. In addition, LSCs expressing CXCL12-cleaving surface protein CD26 were highly correlated with CML burden, building on existing evidence. Newer findings implicate the adhesion molecule CD44 in TKI resistance, while JAK/STAT-mediated resistance to TKIs may occur downstream of extrinsic signalling in the BME. Exosomal BME-LSC cross-communication has also been explored. Finally, further detail on the phenotypes of natural killer (NK) cells putatively involved in maintaining successful TFR has been published, and NK-based immunotherapies are discussed. Recent studies highlight and build on our understanding of the BME in CML persistence and TKI resistance, pinpointing therapeutically vulnerable interactions. Repurposing existing drugs and/or the development of novel inhibitors targeting these relationships may help to overcome these issues in TKI-resistant CML and be used as adjuvant therapy for sustained TFR.

Tumour‑derived exosomes and their emerging roles in leukaemia (Review)

Exosomes are small vesicles with a diameter of ~40-100 nm that are secreted by the majority of endogenous cells under normal and pathological conditions. They contain abundant proteins, lipids, microRNAs, and biomolecules such as signal transduction molecules, adhesion factors and cytoskeletal proteins, and play an important role in exchanging materials and transmitting information between cells. Recent studies have shown that exosomes are involved in the pathophysiology of leukaemia by affecting the bone marrow microenvironment, apoptosis, tumour angiogenesis, immune escape and chemotherapy resistance. Furthermore, exosomes are potential biomarkers and drug carriers for leukaemia, impacting the diagnosis and treatment of leukaemia. The present study describes the biogenesis and general characteristics of exosomes, and then highlight the emerging roles of exosomes in different types of leukaemia. Finally, the value of clinical application of exosomes as biomarkers and drug carriers is discussed with the aim to provide novel strategies for the treatment of leukaemia.

Breast cancer tumor microenvironment affects Treg/IL-17-producing Treg/Th17 cell axis: Molecular and therapeutic perspectives

The tumor microenvironment (TME) comprises a variety of immune cells, among which T cells exert a prominent axial role in tumor development or anti-tumor responses in patients with breast cancer (BC). High or low levels of anti-inflammatory cytokines, such as transforming growth factor β, in the absence or presence of proinflammatory cytokines, such as interleukin-6 (IL-6), delineate the fate of T cells toward either regulatory T (Treg) or T helper 17 (Th17) cells, respectively. The transitional state of RORγt⁺Foxp3⁺ Treg (IL-17-producing Treg) resides in the middle of this reciprocal polarization, which is known as Treg/IL-17-producing Treg/Th17 cell axis. TME secretome, including microRNAs, cytokines, and extracellular vesicles, can significantly affect this axis. Furthermore, immune checkpoint inhibitors may be used to reconstruct immune cells; however, some of these novel therapies may favor tumor development. Therefore, understanding secretory and cell-associated factors involved in their differentiation or polarization and functions may be targeted for BC management. This review discusses microRNAs, cytokines, and extracellular vesicles (as secretome), as well as transcription factors and immune checkpoints (as cell-associated factors), which influence the Treg/IL-17-producing Treg/Th17 cell axis in BC. Furthermore, approved or ongoing clinical trials related to the modulation of this axis in the TME of BC are described to broaden new horizons of promising therapeutic approaches.

Exosomes carrying immune checkpoints, a promising therapeutic approach in cancer treatment

Exosomes are a subgroup of extracellular vesicles generated by distinct cells. Tumor-derived extracellular vesicles convey immunological checkpoint molecules. TEXs as critical mediators in tumor development, metastasis, and immune escape have recently become the focus of scientific research. Exosomes are involved in the regulation of the immune system. Exosomes interact with target cells in the tumor microenvironment, changing their function based on the cargo they contain. Exosomal immune checkpoints might be exploited to track tumor immune evasion, treatment response, and patient prognosis while enhancing tumor cell proliferation and spread. This review focuses on tumor-derived exosomes, their immunosuppressive effects in mice models, and their role in cancer immunotherapy. Exosomes are being studied as possible cancer vaccines, with numerous uses in tumor immunotherapy. Exosomes can carry chemotherapeutics, siRNA, and monoclonal antibodies. Exosomes produced by macrophages might be used to treat cancer. These and other clinical consequences provide new doors for cancer treatment.

Exosome application in treatment and diagnosis of B-cell disorders: leukemias, multiple sclerosis, and arthritis rheumatoid

Exosomes, known as a type of extracellular vesicles (EVs), are lipid particles comprising heterogeneous contents such as nucleic acids, proteins, and DNA. These bi-layered particles are naturally released into the extracellular periphery by a variety of cells such as neoplastic cells. Given that exosomes have unique properties, they can be used as vectors and carriers of biological and medicinal particles like drugs for delivering to the desired areas. The proteins and RNAs being encompassed by the circulating exosomes in B-cell malignancies are deemed as the promising sources for diagnostic and prognostic biomarkers, as well as therapeutic agents. Exosomes can also provide a "snapshot" view of the tumor and metastatic landscape at any particular time. Further, clinical research has shown that exosomes are produced by immune cells such as dendritic cells can stimulate the immune system, so these exosomes can be used in antitumor vaccines. Despite the great potential of exosomes in the fields of diagnostic and treatment, further studies are in need for these purposes to reach a convergence notion. This review highlights the applications of exosomes in multiple immune-related diseases, including chronic lymphocytic leukemia, multiple sclerosis, and arthritis rheumatoid, as well as explaining sundry aspects of exosome therapy and the function of exosomes in diagnosing diseases.

Extracellular Vesicles in Haematological Disorders: A Friend or a Foe?

Extracellular vesicles (EVs) have emerged as important mediators of homeostasis, immune modulation and intercellular communication. They are released by every cell of the human body and accordingly detected in a variety of body fluids. Interestingly, their expression can be upregulated under various conditions, such as stress, hypoxia, irradiation, inflammation, etc. Their cargo, which is variable and may include lipids, proteins, RNAs and DNA, reflects that of the parental cell, which offers a significant diagnostic potential to EVs. In line with this, an increasing number of studies have reported the important contribution of cancer-derived EVs in altering the tumour microenvironment and allowing for cancer progression and metastasis. As such, cancer-derived EVs may be used to monitor the development and progression of disease and to evaluate the potential response to treatment, which has generated much excitement in the field of oncology and particularly in haemato-oncology. Finally, EVs are able to transfer their cargo to target cells, modifying the properties of the recipient cell, which offers great therapeutic potential for EVs (either by specific drug delivery or by delivery of siRNAs and other inhibitory proteins). In this manuscript, we review the potential diagnostic use and therapeutic options of EVs in the context of haematological malignancies.

Immunological and prognostic significance of novel ferroptosis-related genes in soft tissue sarcoma

Background

Ferroptosis has exhibited great potential in the treatment of cancer and has gained widespread attention in soft tissue sarcoma (STS). The aim was to explore the immunological and prognostic significance of novel ferroptosis-related genes in STS.

Methods

We identified ferroptosis-related differentially expressed genes (DEGs) in STS to construct the networks of enrichment analysis and protein-protein interaction. Subsequently, hub genes with prognostic significance were localized and a series of prognostic and immune analyses were performed.

Results

40 ferroptosis-related DEGs were identified, of which HELLS, STMN1 EPAS1, CXCL2, NQO1, and IL6 were classified as hub genes and were associated with the prognosis in STS patients. In the results of the immune analysis, PDCD1, CTLA4, TIGIT, IDO1 and CD27 exhibited consistent intense correlations as immune checkpoint genes, as well as macrophage, neutrophil, cytotoxic cell, dendritic cell, interdigitating dendritic cell and plasmacytoid dendritic cell as immune cells. EPAS1 and HELLS might be independent prognostic factors for STS patients, and separate prognostic models were constructed by using them.

Conclusions

We recognized novel ferroptosis-related genes with prognostic value in STS. Furthermore, we searched out potential immune checkpoints and critical immune cells.