Search results for " growth"

Alkaline phosphatase dual-binding sites for collagen dictate cell migration and microvessel assembly in vitro

2020

Interactions between cell types, growth factors, and extracellular matrix components involved in angiogenesis are crucial for new vessel formation leading to tissue regeneration. This study investigated whether cocultures of fibroblasts and endothelial cells (ECs; from macro- or microvasculature) play a role in the formation of microvessel-like structures by ECs, as well as modulate fibroblast differentiation and growth factors production (vascular endothelial cell growth factor, basic fibroblast growth factor, active transforming growth factor-beta 1, and interleukin-8), which are important for vessel sprouting and maturation. Data obtained revealed that in vitro coculture systems of fibro…

Thymus-derived regulatory T cells are positively selected on natural self-antigen through cognate interactions of high functional avidity

2016

Regulatory T (Treg) cells expressing Foxp3 transcripton factor are essential for immune homeostasis. They arise in the thymus as a separate lineage from conventional CD4+Foxp3- T (Tconv) cells. Here, we show that the thymic development of Treg cells depends on the expression of their endogenous cognate self-antigen. The formation of these cells was impaired in mice lacking this self-antigen, while Tconv cell development was not negatively affected. Thymus-derived Treg cells were selected by self-antigens in a specific manner, while autoreactive Tconv cells were produced through degenerate recognition of distinct antigens. These distinct modes of development were associated with the expressi…

Influence of different calcium phosphate ceramics on growth and differentiation of cells in osteoblast-endothelial co-cultures

2016

Strategies for improvement of angiogenesis and vasculogenesis using different cells and materials are paramount aims in the field of bone tissue engineering. Thereby, the interaction between different cell types and scaffold materials is crucial for growth, differentiation, and long-term outcomes of tissue-engineered constructs. In this study, we evaluated the interaction of osteoblasts and endothelial cells in three-dimensional tissue-engineered constructs using beta tricalciumphosphate (β-TCP, [s-Ca3 (PO4 )2 ]) and calcium-deficient hydroxyapatite (CDHA, [Ca9 (PO4 )5 (HPO4 )OH]) ceramics as scaffolds. We focused on initial cell organization, cell proliferation, and differential expression…

Neurofibromatosis type 2 tumor suppressor protein is expressed in oligodendrocytes and regulates cell proliferation and process formation.

2017

The neurofibromatosis type 2 (NF2) tumor suppressor protein Merlin functions as a negative regulator of cell growth and actin dynamics in different cell types amongst which Schwann cells have been extensively studied. In contrast, the presence and the role of Merlin in oligodendrocytes, the myelin forming cells within the CNS, have not been elucidated. In this work, we demonstrate that Merlin immunoreactivity was broadly distributed in the white matter throughout the central nervous system. Following Merlin expression during development in the cerebellum, Merlin could be detected in the cerebellar white matter tract at early postnatal stages as shown by its co-localization with Olig2-positi…

Chemical Composition, In Vitro Antitumor and Pro-Oxidant Activities of Glandora rosmarinifolia (Boraginaceae) Essential Oil

2018

The biological properties of essential oils have been demonstrated in the treatment of several diseases and to enhance the bioavailability of other drugs. In natural habitats the essential oils compounds may play important roles in the protection of the plants as antibacterials, antivirals, antifungals, insecticides and also against herbivores by reducing their appetite for such plants or by repelling undesirable others. We analyzed by gas-chromatography mass spectrometry the chemical composition of the essential oil of aerial parts of Glandora rosmarinifolia (Ten.) D.C. Thomas obtained by hydrodistillation and verified some biological activities on a panel of hepatocellular carcinoma cell …

2020

PIK3CA-related overgrowth spectrum is caused by mosaicism mutations in the PIK3CA gene. These mutations, which are also observed in various types of cancer, lead to a constitutive activation of the PI3K/AKT/mTOR pathway, increasing cell proliferation. Heat shock transcription factor 1 (HSF1) is the major stress-responsive transcription factor. Recent findings indicate that AKT phosphorylates and activates HSF1 independently of heat-shock in breast cancer cells. Here, we aimed to investigate the role of HSF1 in PIK3CA-related overgrowth spectrum. We observed a higher rate of proliferation and increased phosphorylation of AKT and p70S6K in mutant fibroblasts than in control cells. We also fou…

Copper/MYC/CTR1 interplay: A dangerous relationship in hepatocellular carcinoma

2018

Free serum copper correlates with tumor incidence and progression of human cancers, including hepatocellular carcinoma (HCC). Copper extracellular uptake is provided by the transporter CTR1, whose expression is regulated to avoid excessive intracellular copper entry. Inadequate copper serum concentration is involved in the pathogenesis of Non Alcoholic Fatty Liver Disease (NAFLD), which is becoming a major cause of liver damage progression and HCC incidence. Finally, MYC is over-expressed in most of HCCs and is a critical regulator of cellular growth, tumor invasion and metastasis. The purpose of our study was to understand if higher serum copper concentrations might be involved in the prog…

2017

Although a lot of research has been performed, large segmental bone defects caused by trauma, infection, bone tumors or revision surgeries still represent big challenges for trauma surgeons. New and innovative bone substitutes are needed. Three-dimensional (3D) printing is a novel procedure to create 3D porous scaffolds that can be used for bone tissue engineering. In the present study, solid discs as well as porous cage-like 3D prints made of polylactide (PLA) are coated or filled with collagen, respectively, and tested for biocompatibility and endotoxin contamination. Microscopic analyses as well as proliferation assays were performed using various cell types on PLA discs. Stromal-derived…

Stem cell functionality is microenvironmentally defined during tumour expansion and therapy response in colon cancer

2018

Solid malignancies have been speculated to depend on cancer stem cells (CSCs) for expansion and relapse after therapy. Here we report on quantitative analyses of lineage tracing data from primary colon cancer xenograft tissue to assess CSC functionality in a human solid malignancy. The temporally obtained clone size distribution data support a model in which stem cell function in established cancers is not intrinsically, but is entirely spatiotemporally orchestrated. Functional stem cells that drive tumour expansion predominantly reside at the tumour edge, close to cancer-associated fibroblasts. Hence, stem cell properties change in time depending on the cell location. Furthermore, although…

Cancer combination therapy of the sesquiterpenoid artesunate and the selective EGFR-tyrosine kinase inhibitor erlotinib.

2017

Abstract Background The shift from cytotoxic to targeted chemotherapy led to improved treatment outcomes in oncology. Nevertheless, many cancer patients cannot be cured from their disease because of the development of drug resistance and side effects. Purpose There is an ongoing quest for novel compounds, which raised not only the interest in natural products but also in novel combination therapy regimens. Study design In this review, we report on the inhibition epidermal growth factor receptor (EGFR) by targeted small molecules and their combination with natural products from medicinal plants. Results The combination of erlotinib with artesunate leads to synergistic inhibition of cell grow…