Search results for "microenvironment"
showing 10 items of 369 documents
Transmission of Information in Neoplasia by Extracellular Vesicles.
2015
Paracrine interactions among neoplastic and nonneoplastic cells in the immediate tumor microenvironment are important for tumor growth and metastatic spreading. Most of the studies in the past decade addressing these cellular interactions have focused on tumor cell-derived soluble molecules. Recently, these studies and interest have shifted to nanosized extracellular vesicles (EVs) and especially ectosome and exosome-associated molecules [1]. They contain not only proteins, but also lipids, mRNA, and microRNA [1], which can regulate gene expression in their target cells in a much more pleiotropic manner [1]. While exosomes originate by a sequential process of inward budding of late endosome…
Hematologic malignancies: The exosome contribution in tumor progression
2020
Abstract The bone marrow, composed of cells, extracellular matrix, and soluble factors, such as cytokines, chemokines and signaling molecules, provides a favorable microenvironment for hematologic tumor progression and for the development of drug resistance. Recently, extracellular vesicles (EVs), released by tumor and surrounding cells, have emerged as important players within the bone marrow niche. Here we will discuss the current knowledge on the EV- mediated crosstalk between tumor and normal cells, in order to better understand how vesicles can contribute to tumor progression. Advances in the knowledge of the role of cell-derived EVs in tumor microenvironment highlight the possibility …
CCL3 and CCL4, the Major Chemokines Produced by CD38+ Chronic Lymphocytic Leukemia Cells, Facilitate Microenvironmental Interactions of Neoplastic Ce…
2008
Abstract CD38, a negative prognostic marker for patients with CLL, has been demonstrated to be a key molecule in the interactions occurring in the context of tumor microenvironment, mediating both survival and migratory signals for CLL cells. By taking advantage of gene expression profiling studies (GEP) comparing 11 CD38pos (CD38>30%) and 15 CD38neg (CD38<10%) CLLs, we identified as over-expressed in CD38pos CLL cells: i) genes for the two C-C chemokines CCL3 and CCL4 (median-log difference, MLD-CCL3= 3.5; MLD-CCL4=4.4); real-time quantitative PCR (RTQ-PCR) of selected cases confirmed GEP results; ii) the gene for CD49d (MLD=4.4); a high correlation between CD38 and CD49d pro…
Complement Component 3 expressed by the endometrial ectopic tissue is involved in the endometriotic lesion formation through mast cell activation
2020
AbstractThe pathophysiology of endometriosis (EM) is an excellent example of immune dysfunction, reminiscent of tumor microenvironment as well. Here, we report that an interplay between C3 and mast cells (MCs) is involved in the pathogenesis of ectopic EM. C3 is at the epicenter of the regulatory feed forward loop, amplifying the inflammatory microenvironment, in which the MCs are protagonists. Thus, C3 can be considered a marker of EM and its local synthesis can promote the engraftment of the endometriotic cysts. We generated a murine model of EM via injection of minced uterine tissue from a donor mouse, into the peritoneum of the recipient mice. The wild type mice showed greater amount of…
Targeting cancer stem cells and the tumor microenvironment
2015
Compelling evidence indicates that the survival and behavior of cancer stem cells (CSCs) are positively regulated by specific stimuli received from the tumor microenvironment, which dictates the maintenance of stemness, invasiveness, and protection against drug-induced apoptotic signals. CSCs are per se endowed with multiple treatment resistance capabilities, thus the eradication of CSC pools offers a precious strategy in achieving a long-term cancer remission. Numerous therapies, aimed at eradicating CSCs, have been elaborated such as: (i) selective targeting of CSCs, (ii) modulating their stemness and (iii) influencing the microenvironment. In this context, markers commonly exploited to i…
2019
Glycoprotein A repetition predominant (GARP), a specific surface molecule of activated regulatory T cells, has been demonstrated to significantly contribute to tolerance in humans by induction of peripheral Treg and regulatory M2-macrophages and by inhibition of (tumorantigen-specific) T effector cells. Previous work identified GARP on Treg, and also GARP on the surface of several malignant tumors, as well as in a soluble form being shedded from their surface, contributing to tumor immune escape. Preliminary results also showed GARP expression on brain metastases of malignant melanoma. On the basis of these findings, we investigated whether GARP is also expressed on primary brain tumors. We…
Tumor infiltration by chemokine receptor 7 (CCR7)+ T-lymphocytes is a favorable prognostic factor in metastatic colorectal cancer
2012
The immune interactions occurring within the tumor microenvironment have a critical role in determining the outcome of colorectal cancer patients. We carried-out an immunohistochemical analysis of tumor infiltrating T-lymphocytes expressing chemokine receptor 7 (CCR7) in a series of colorectal cancer patients enrolled in a prospective clinical trial. We demonstrated that a high tumor infiltration score of this lymphocyte subset is predictive of longer progression free survival and overall survival. © 2012 Landes Bioscience.
Exosomal Hsp60: A Tumor Biomarker?
2019
Exosomes (EXs) are extracellular vesicles containing proteins, DNA, mRNA, non-coding RNAs, such as miRNAs, and lipid. The EXs can be easily isolated from different biological fluids and their content is considered a potential biomarker in various diseases, such as cancer. EXs play an important role in intercellular communication, permitting cells to exchange proteins, lipids, and genetic material in normal and pathological conditions. New data have shown that tumor cells-derived EXs contribute to cancer progression through the modulation of tumor microenvironment. Heat shock proteins 60 kDa (Hsp60) is classically considered mitochondrial proteins with different biological roles. In recent y…
Zebrafish xenografts as a tool for in vivo studies on human cancer
2012
The zebrafish has become a powerful vertebrate model for genetic studies of embryonic development and organogenesis and increasingly for studies in cancer biology. Zebrafish facilitate the performance of reverse and forward genetic approaches, including mutagenesis and small molecule screens. Moreover, several studies report the feasibility of xenotransplanting human cells into zebrafish embryos and adult fish. This model provides a unique opportunity to monitor tumor-induced angiogenesis, invasiveness, and response to a range of treatments in vivo and in real time. Despite the high conservation of gene function between fish and humans, concern remains that potential differences in zebrafis…
Strikingly High Respiratory Quotients: A Further Characteristic of the Tumor Pathophysiome
2008
Conspicuously high respiratory quotients (RQs) are found in solid tumors in vivo. RQs in the range between 1.29 and 1.95 neither reflect the degree of substrate oxidation by tumor cells nor indicate the types of fuels involved in metabolic processes. Instead, such tumor RQs most probably are caused by (a) channeling of glycolytic end-products into lipogenesis, and by (b) CO2 release from the tumor following extracellular buffering of H+ -inos by bicarbonate. H+ -inos exported from the intracellular space into the interstitial compartment titrate extracellular bicarbonate to CO2 and H2O with the aid of the ectoenzyme carbonic anhydrase IX, which is activated at low pH. Strikingly high (RQs) …