scholarly journals Restoring Tissue Homeostasis at Metastatic Sites: A Focus on Extracellular Vesicles in Bone Metastasis

2021 ◽  
Vol 11 ◽  
Author(s):  
Domenica Giannandrea ◽  
Valentina Citro ◽  
Elena Lesma ◽  
Monica Bignotto ◽  
Natalia Platonova ◽  
...  

Bone is the most common site of cancer metastasis and the spread of cancer cells to the bone is associated with poor prognosis, pain, increased risk of fractures, and hypercalcemia. The bone marrow microenvironment is an attractive place for tumor dissemination, due to the dynamic network of non-malignant cells. In particular, the alteration of the bone homeostasis favors the tumor homing and the consequent osteolytic or osteoblastic lesions. Extracellular vesicles (EVs) are reported to be involved in the metastatic process, promoting tumor invasion, escape from immune surveillance, extravasation, extracellular matrix remodeling, and metastasis, but the role of EVs in bone metastases is still unclear. Current results suggest the ability of tumor derived EVs in promoting bone localization and metastasis formation, altering the physiological balance between bone destruction and new bone depositions. Moreover, EVs from the bone marrow niche may support the onset of tumor metastasis. This review summarizes recent findings on the role of EVs in the pathological alterations of homeostasis that occur during bone metastasis to show novel potential EV-based therapeutic options to inhibit metastasis formation.

2018 ◽  
Vol 4 (2) ◽  
pp. 80-87
Author(s):  
Terhi J. Heino ◽  
Jorma A. Määttä

2022 ◽  
pp. 1-10
Author(s):  
Patrick Wuchter ◽  
Anke Diehlmann ◽  
Harald Klüter

<b><i>Background:</i></b> The stem cell niche in human bone marrow provides scaffolds, cellular frameworks and essential soluble cues to support the stemness of hematopoietic stem and progenitor cells (HSPCs). To decipher this complex structure and the corresponding cellular interactions, a number of in vitro model systems have been developed. The cellular microenvironment is of key importance, and mesenchymal stromal cells (MSCs) represent one of the major cellular determinants of the niche. Regulation of the self-renewal and differentiation of HSPCs requires not only direct cellular contact and adhesion molecules, but also various cytokines and chemokines. The C-X-C chemokine receptor type 4/stromal cell-derived factor 1 axis plays a pivotal role in stem cell mobilization and homing. As we have learned in recent years, to realistically simulate the physiological in vivo situation, advanced model systems should be based on niche cells arranged in a three-dimensional (3D) structure. By providing a dynamic rather than static setup, microbioreactor systems offer a number of advantages. In addition, the role of low oxygen tension in the niche microenvironment and its impact on hematopoietic stem cells need to be taken into account and are discussed in this review. <b><i>Summary:</i></b> This review focuses on the role of MSCs as a part of the bone marrow niche, the interplay between MSCs and HSPCs and the most important regulatory factors that need to be considered when engineering artificial hematopoietic stem cell niche systems. <b><i>Conclusion:</i></b> Advanced 3D model systems using MSCs as niche cells and applying microbioreactor-based technology are capable of simulating the natural properties of the bone marrow niche more closely than ever before.


Cells ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 2316
Author(s):  
Lucia Catani ◽  
Michele Cavo ◽  
Francesca Palandri

Myeloproliferative Neoplasms (MPN) are acquired clonal disorders of the hematopoietic stem cells and include Essential Thrombocythemia, Polycythemia Vera and Myelofibrosis. MPN are characterized by mutations in three driver genes (JAK2, CALR and MPL) and by a state of chronic inflammation. Notably, MPN patients experience increased risk of thrombosis, disease progression, second neoplasia and evolution to acute leukemia. Extracellular vesicles (EVs) are a heterogeneous population of microparticles with a role in cell-cell communication. The EV-mediated cross-talk occurs via the trafficking of bioactive molecules such as nucleic acids, proteins, metabolites and lipids. Growing interest is focused on EVs and their potential impact on the regulation of blood cancers. Overall, EVs have been suggested to orchestrate the complex interplay between tumor cells and the microenvironment with a pivotal role in “education” and “crafting” of the microenvironment by regulating angiogenesis, coagulation, immune escape and drug resistance of tumors. This review is focused on the role of EVs in MPN. Specifically, we will provide an overview of recent findings on the involvement of EVs in MPN pathogenesis and discuss opportunities for their potential application as diagnostic and prognostic biomarkers.


Author(s):  
Florian Puhm ◽  
Eric Boilard ◽  
Kellie R. Machlus

Extracellular vesicles (EVs) are a means of cell-to-cell communication and can facilitate the exchange of a broad array of molecules between adjacent or distant cells. Platelets are anucleate cells derived from megakaryocytes and are primarily known for their role in maintaining hemostasis and vascular integrity. Upon activation by a variety of agonists, platelets readily generate EVs, which were initially identified as procoagulant particles. However, as both platelets and their EVs are abundant in blood, the role of platelet EVs in hemostasis may be redundant. Moreover, findings have challenged the significance of platelet-derived EVs in coagulation. Looking beyond hemostasis, platelet EV cargo is incredibly diverse and can include lipids, proteins, nucleic acids, and organelles involved in numerous other biological processes. Furthermore, while platelets cannot cross tissue barriers, their EVs can enter lymph, bone marrow, and synovial fluid. This allows for the transfer of platelet-derived content to cellular recipients and organs inaccessible to platelets. This review highlights the importance of platelet-derived EVs in physiological and pathological conditions beyond hemostasis.


Leukemia ◽  
2020 ◽  
Vol 34 (9) ◽  
pp. 2305-2316 ◽  
Author(s):  
Julia Zinngrebe ◽  
Klaus-Michael Debatin ◽  
Pamela Fischer-Posovszky

Abstract The bone marrow is home to well-balanced normal hematopoiesis, but also the stage of leukemia’s crime. Marrow adipose tissue (MAT) is a unique and versatile component of the bone marrow niche. While the importance of MAT for bone health has long been recognized, its complex role in hematopoiesis has only recently gained attention. In this review article we summarize recent conceptual advances in the field of MAT research and how these developments impact our understanding of MAT regulation of hematopoiesis. Elucidating routes of interaction and regulation between MAT and cells of the hematopoietic system are essential to pinpoint vulnerable processes resulting in malignant transformation. The concept of white adipose tissue contributing to cancer development and progression on the cellular, metabolic, and systemic level is generally accepted. The role of MAT in malignant hematopoiesis, however, is controversial. MAT is very sensitive to changes in the patient’s metabolic status hampering a clear definition of its role in different clinical situations. Here, we discuss future directions for leukemia research in the context of metabolism-induced modifications of MAT and other adipose tissues and how this might impact on leukemia cell survival, proliferation, and antileukemic therapy.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 2426-2426
Author(s):  
Victoria J Forster ◽  
Patricia Garrido Castro ◽  
Amy K Bradburn ◽  
James M Allan ◽  
Olaf Heidenreich

Abstract Abstract 2426 BACKGROUND The chromosomal rearrangement t(8;21)(q22;q22) encodes the fusion gene AML1/ETO, which is the most common translocation in acute myeloid leukemia (AML). It has an incidence of approximately 15% and a favourable prognosis in comparison to other AML subtypes. Dysregulated angiogenesis in the bone marrow niche environment is predicted to have an important role in leukemia pathogenesis, and several factors have been implicated in this process. Angiopoietin-1 (ANGPT1) is a cytokine involved in hematopoietic stem cell quiescence and regulation of microvessel density within the bone marrow, as well as having a role in transendothelial migration. Moreover, ANGPT1 is upregulated in leukemic blast cells from AML patients. In this study we investigated the role of AML1/ETO as a regulator of ANGPT1 expression, as well as functional implications of ANGPT1 in AML1/ETO-positive AML. METHODS In order to investigate putative AML1/ETO-dependent regulation of ANGPT1, we performed gain-of-function studies using lentiviral gene transfer to ectopically express AML1/ETO in HL-60 and U937 AML cell lines. We also depleted AML1/ETO in the t(8;21)-positive AML cell line Kasumi-1 using fusion gene specific siRNA. Additionally, the functional role of ANGPT1 was studied using targeted RNAi in Kasumi-1 cells. Transcript expression of AML1/ETO and ANGPT1 was analysed by quantitative Real-Time PCR (qRT-PCR) and AML1/ETO protein expression was quantified by western blotting. Angiopoietin-1 protein secretion was determined using enzyme-linked immunosorbent assay (ELISA). We also utilised Matrigel transwell assays to test the effect of ANGPT1 downregulation on the invasive and migratory properties of Kasumi-1. RESULTS In HL-60 and U937 transduced with AML1/ETO, we observed an up to 280 fold increase in ANGPT1 mRNA transcript levels as measured by qRT-PCR, which correlated with an increase in secreted Angiopoietin-1 protein. Conversely, siRNA-mediated AML1/ETO depletion in Kasumi-1 cells significantly decreased ANGPT1 transcript and protein levels after a single electroporation. After three serial electroporations with siRNA, AML1/ETO transcript levels were reduced by 85%, with a concomitant decline in ANGPT1 transcript (>99%) and secreted protein. Preliminary data suggest siRNA targeting of ANGPT1 in Kasumi-1 decreases the invasive ability of these cells, causing a ≥50% reduction in invasion when compared to controls. CONCLUSIONS We have identified a strong correlation between AML1/ETO and ANGPT1 expression, whereby a reduction of AML1/ETO results in a substantial reduction of ANGPT1. Similarly, the introduction of AML1/ETO into myeloid cell lines results in a large upregulation of ANGPT1. Preliminary evidence suggests that a reduction of ANGPT1 reduces the invasive and migratory potential of Kasumi-1. This could have major functional consequences in the bone marrow niche with regards to understanding the AML stem cell and its interaction with the niche environment as well as providing insight into how leukemic cells in the circulation might interact with the vasculature. Disclosures: No relevant conflicts of interest to declare.


2012 ◽  
Vol 1266 (1) ◽  
pp. 72-77 ◽  
Author(s):  
Fumio Arai ◽  
Kentaro Hosokawa ◽  
Hirofumi Toyama ◽  
Yoshiko Matsumoto ◽  
Toshio Suda

Author(s):  
Paul Takam Kamga ◽  
Riccardo Bazzoni ◽  
Giada Dal Collo ◽  
Adriana Cassaro ◽  
Ilaria Tanasi ◽  
...  

Notch and Wnt signaling are highly conserved intercellular communication pathways involved in developmental processes, such as hematopoiesis. Even though data from literature support a role for these two pathways in both physiological hematopoiesis and leukemia, there are still many controversies concerning the nature of their contribution. Early studies, strengthened by findings from T-cell acute lymphoblastic leukemia (T-ALL), have focused their investigation on the mutations in genes encoding for components of the pathways, with limited results except for B-cell chronic lymphocytic leukemia (CLL); in because in other leukemia the two pathways could be hyper-expressed without genetic abnormalities. As normal and malignant hematopoiesis require close and complex interactions between hematopoietic cells and specialized bone marrow (BM) niche cells, recent studies have focused on the role of Notch and Wnt signaling in the context of normal crosstalk between hematopoietic/leukemia cells and stromal components. Amongst the latter, mesenchymal stromal/stem cells (MSCs) play a pivotal role as multipotent non-hematopoietic cells capable of giving rise to most of the BM niche stromal cells, including fibroblasts, adipocytes, and osteocytes. Indeed, MSCs express and secrete a broad pattern of bioactive molecules, including Notch and Wnt molecules, that support all the phases of the hematopoiesis, including self-renewal, proliferation and differentiation. Herein, we provide an overview on recent advances on the contribution of MSC-derived Notch and Wnt signaling to hematopoiesis and leukemia development.


Sign in / Sign up

Export Citation Format

Share Document