Nuclear factor-κB activation by transforming growth factor-β1 drives tumour microenvironment-mediated drug resistance in neuroblastoma.

Background: Intrinsic and extrinsic factors in the tumour microenvironment (TME) contribute to therapeutic resistance. Here we demonstrate that transforming growth factor (TGF)-β1 produced in the TME increased drug resistance of neuroblastoma (NB) cells.

Methods: Human NB cell lines were tested in vitro for their sensitivity to Doxorubicin (DOX) and Etoposide (ETOP) in the presence of tumour-associated macrophages (TAM) and mesenchymal stromal cells/cancer-associated fibroblasts (MSC/CAF).

The capture of extracellular vesicles endogenously released by xenotransplanted tumours induces an inflammatory reaction in the premetastatic niche.

The capture of tumour-derived extracellular vesicles (TEVs) by cells in the tumour microenvironment (TME) contributes to metastasis and notably to the formation of the pre-metastatic niche (PMN). However, due to the challenges associated with modelling release of small EVs in vivo, the kinetics of PMN formation in response to endogenously released TEVs have not been examined. Here, we have studied the endogenous release of TEVs in mice orthotopically implanted with metastatic human melanoma (MEL) and neuroblastoma (NB) cells releasing GFP-tagged EVs (GFTEVs) and their capture by host cells to demonstrate the active contribution of TEVs to metastasis.

Fibroblasts and macrophages cooperate to create a pro-tumorigenic and immune resistant environment via activation of TGF-β/IL-6 pathway in neuroblastoma.

Tumor-associated macrophages (TAM) and cancer-associated fibroblasts (CAF) and their precursor mesenchymal stromal cells (MSC) are often detected together in tumors, but how they cooperate is not well understood. Here, we show that TAM and CAF are the most abundant nonmalignant cells and are present together in untreated human neuroblastoma (NB) tumors that are also poorly infiltrated with T and natural killer (NK) cells. We then show that MSC and CAF-MSC harvested from NB tumors protected human monocytes (MN) from spontaneous apoptosis in an interleukin (IL)-6 dependent mechanism.

The Tumor Microenvironment in Neuroblastoma: New Players, New Mechanisms of Interaction and New Perspectives.

The contribution of the tumor microenvironment (TME) to cancer progression has been well recognized in recent decades. As cancer therapeutic strategies are increasingly precise and include immunotherapies, knowledge of the nature and function of the TME in a tumor becomes essential. Our understanding of the TME in neuroblastoma (NB), the second most common solid tumor in children, has significantly progressed from an initial focus on its Schwannian component to a better awareness of its complex nature, which includes not only immune but also non-immune cells such as cancer-associated fibroblasts (CAFs), the contribution of which to inflammation and interaction with tumor-associated macrophages (TAMs) is now recognized.

Extracellular Vesicle and Particle Biomarkers Define Multiple Human Cancers.

There is an unmet clinical need for improved tissue and liquid biopsy tools for cancer detection. We investigated the proteomic profile of extracellular vesicles and particles (EVPs) in 426 human samples from tissue explants (TEs), plasma, and other bodily fluids. Among traditional exosome markers, CD9, HSPA8, ALIX, and HSP90AB1 represent pan-EVP markers, while ACTB, MSN, and RAP1B are novel pan-EVP markers.

Anti-CD105 Antibody Eliminates Tumor Microenvironment Cells and Enhances Anti-GD2 Antibody Immunotherapy of Neuroblastoma with Activated Natural Killer Cells.

Purpose: We determined whether elimination of CD105 cells in the tumor microenvironment (TME) with anti-CD105 antibodies enhanced anti-disialoganglioside (GD2) antibody dinutuximab therapy of neuroblastoma when combined with activated natural killer (aNK) cells.

Experimental Design: The effect of MSCs and monocytes on antibody-dependent cellular cytotoxicity (ADCC) mediated by dinutuximab with aNK cells against neuroblastoma cells was determined . ADCC with anti-CD105 mAb TRC105 and aNK cells against MSCs, monocytes, and endothelial cells, which express CD105, was evaluated.

Cancer-Associated Fibroblasts Share Characteristics and Protumorigenic Activity with Mesenchymal Stromal Cells.

Cancer-associated fibroblasts (CAF) have been suggested to originate from mesenchymal stromal cells (MSC), but their relationship with MSCs is not clear. Here, we have isolated from primary human neuroblastoma tumors a population of αFAP- and FSP-1-expressing CAFs that share phenotypic and functional characteristics with bone marrow-derived MSCs (BM-MSC). Analysis of human neuroblastoma tumors also confirmed the presence of αFAP- and FSP-1-positive cells in the tumor stroma, and their presence correlated with that of M2 tumor-associated macrophages.

Interaction between bone marrow stromal cells and neuroblastoma cells leads to a VEGFA-mediated osteoblastogenesis.

The potential role of osteoblasts in bone and bone marrow (BM) metastases in neuroblastoma (NBL) remains unclear. In this study, we examined the effect of NBL cells on the osteoblastic differentiation of BM-derived mesenchymal stromal cells (BMMSC). We show that the presence of NBL cells enhanced the osteoblastic differentiation of BMMSC driven by bone morphogenetic protein (BMP)-4, in the absence of any effect on NBL cell proliferation.

Bone marrow-derived mesenchymal stromal cells promote survival and drug resistance in tumor cells.

Bone marrow mesenchymal stromal cells (BMMSC) have antitumorigenic activities. Here, we hypothesized that circulating BMMSC are incorporated into tumors and protect tumor cells from therapy-induced apoptosis. Adherent cells harvested from murine bone marrow and expressing phenotypic and functional characteristics of BMMSC were tested for their antitumor activity against murine 4T1 mammary adenocarcinoma and LL/2 Lewis lung carcinoma cells.

Stromelysin-1 (MMP-3) is a target and a regulator of Wnt1-induced epithelial-mesenchymal transition (EMT).

Matrix metalloproteinases (MMPs) play a well-defined role in later stages of tumor progression. However, there has been evidence that they also contribute to earlier stages of malignant transformation. The Wnt signaling transduction pathway plays a critical role in development and in the pathogenesis of many epithelial cancers.

Modifying the soil to affect the seed: role of stromal-derived matrix metalloproteinases in cancer progression.

In the 1980's, as the importance of matrix metalloproteinases (MMPs) in cancer progression was discovered, it was recognized that in most tumors these proteases were abundantly and sometimes exclusively expressed not by tumor cells, but by normal host-derived cells like fibroblasts, vascular endothelial cells, myofibroblasts, pericytes or inflammatory cells that contribute to the tumor microenvironment. Later experiments in mice deficient in specific MMPs revealed that host-derived MMPs play a critical role not only in tumor cell invasion, but also in carcinogenesis, angiogenesis, vasculogenesis and metastasis. Tumor cells secrete many factors, cytokines and chemokines that directly or indirectly increase the expression of these MMPs in the tumor microenvironment where they exert extracellular matrix (ECM) degrading and sheddase activities.

Matrix metalloproteinases play an active role in Wnt1-induced mammary tumorigenesis.

The Wnt signaling transduction pathway plays a critical role in the pathogenesis of several murine and human epithelial cancers. Here, we have used mouse mammary tumor virus (MMTV)-Wnt1 transgenic mice, which develop spontaneous mammary adenocarcinoma, to examine whether matrix metalloproteinases (MMPs)--a family of extracellular proteases implicated in multiple steps of cancer progression--contributed to Wnt1-induced tumorigenesis. An analysis of the expression of several MMPs by RT-PCR and in situ hybridization revealed an increase in the expression of MMP-2, MMP-3, MMP-9, MMP-13, and MT1-MMP (MMP-14) in hyperplastic glands and in mammary tumors of MMTV-Wnt1 transgenic mice.

Considering the critical interface between tumor cells and stromal cells in the search for targets for anticancer therapy.

In this issue of Cancer Cell, a paper by Lynch et al. demonstrates how the careful study of changes that occur at the interface between tumor cells and stromal cells led to the discovery of a new function for matrix metalloproteinase-7 (MMP-7) in the formation of osteolytic lesions in prostate cancer. The data suggest that MMP-7 inhibition could be a therapeutic target in prostate cancer.

The contribution of bone marrow-derived cells to the tumor vasculature in neuroblastoma is matrix metalloproteinase-9 dependent.

The contribution of the tumor stroma to cancer progression has been increasingly recognized. We had previously shown that in human neuroblastoma tumors orthotopically implanted in immunodeficient mice, stromal-derived matrix metalloproteinase-9 (MMP-9) contributes to the formation of a mature vasculature by promoting pericyte recruitment along endothelial cells. Here we show that MMP-9 is predominantly expressed by bone marrow-derived CD45-positive leukocytes.

Matrix metalloproteinases (MMP) and cathepsin K contribute differently to osteoclastic activities.

The best established proteolytic event of osteoclasts is bone matrix solubilization by the cysteine proteinase cathepsin K. Here, however, we draw the attention on osteoclastic activities depending on matrix metalloproteinases (MMPs). We discuss the observations supporting that MMPs contribute significantly to bone matrix solubilization in specific areas of the skeleton and in some developmental and pathological situations.

TGF-beta3-induced palatogenesis requires matrix metalloproteinases.

Cleft lip and palate syndromes are among the most common congenital malformations in humans. Mammalian palatogenesis is a complex process involving highly regulated interactions between epithelial and mesenchymal cells of the palate to permit correct positioning of the palatal shelves, the remodeling of the extracellular matrix (ECM), and subsequent fusion of the palatal shelves. Here we show that several matrix metalloproteinases (MMPs), including a cell membrane-associated MMP (MT1-MMP) and tissue inhibitor of metalloproteinase-2 (TIMP-2) were highly expressed by the medial edge epithelium (MEE).

Tissue inhibitors of matrix metalloproteinases in cancer.

Tissue inhibitors of metalloproteinases (TIMPs) play a key regulatory role in the homeostasis of the extracellular matrix (ECM) by controlling the activity of matrix metalloproteinases (MMPs). Some TIMPs have a second function as well, unrelated to their antiMMP activity, which affects cell proliferation and survival. The role of these inhibitors in cancer has been the subject of extensive investigations that have examined their biological activity in tumor growth, invasion, metastasis and angiogenesis, as well as their potential use in the diagnosis and treatment of human cancer.

Tissue inhibitors of metalloproteinases (TIMP) in invasion and proliferation.

Tissue inhibitors of matrix metalloproteinases (TIMPs) are a family of natural inhibitors that control the activity of matrix metalloproteinases (MMPs) in the extracellular matrix (ECM). Four members of this family have been so far characterized in a variety of species. These inhibitors share a similar structural feature characterized by the presence of 12 cysteine residues involved in disulfide bonds and a similar function by their ability to form inhibitory complexes with MMPs.

Tissue inhibitor of metalloproteinases-2 is expressed in the interstitial matrix in adult mouse organs and during embryonic development.

Tissue inhibitor of metalloproteinases-2 (TIMP-2) is a member of a family of inhibitors of matrix-degrading metalloproteinases. A better insight into the role of this inhibitor during development and in organ function was obtained by examining the temporospatial expression of TIMP-2 in mice. Northern blot analysis indicated high levels of TIMP-2 mRNA in the lung, skin, reproductive organs, and brain.

Overexpression of tissue inhibitor of metalloproteinases-2 retroviral-mediated gene transfer in vivo inhibits tumor growth and invasion.

We have demonstrated previously that overexpression of tissue inhibitor of metalloproteinases-2 (TIMP-2), an inhibitor of matrix-degrading metalloproteinases, not only inhibits the invasive and metastatic behavior of tumor cells but also significantly decreases tumor growth in vivo (Y. A. DeClerck et at, Cancer Res.

Matrix metalloproteinases are obligatory for the migration of preosteoclasts to the developing marrow cavity of primitive long bones.

A key event in bone resorption is the recruitment of osteoclasts to future resorption sites. We follow here the migration of preosteoclasts from the periosteum to the developing marrow cavity of fetal mouse metatarsals in culture, and investigate the role of proteinases and demineralization in this migration. Our approach consisted in testing inhibitors of proteinases and demineralization on the migration kinetics.