Search results for "Cell growth"
showing 10 items of 662 documents
Extracorporeal shock waves increase markers of cellular proliferation in primary bronchial fibroblasts of COPD patients
2019
COPD is due to a remodeling of small airways and destruction of the lung parenchyma with loss of the alveolar attachment as a result of pulmonary emphysema. Treatment of connective tissue fibroblasts with extracorporeal shock waves (ESW) increases their cellular proliferation and differentiation. To date no studies are available on ESW treatment of human primary bronchial fibroblasts from COPD and control subjects. Primary bronchial fibroblasts were obtained from bronchial biopsies from three patients with mild/moderate COPD and 3 control smokers with normal lung function. After stabilization for 24h, 1 ml of cell suspension (106 cells) from COPD and controls was treated in 2 ml tubes with …
Collagen-embedded hydroxylapatite–beta-tricalcium phosphate–silicon dioxide bone substitute granules assist rapid vascularization and promote cell gr…
2010
In the present study we assessed the biocompatibility in vitro and in vivo of a low-temperature sol-gel-manufactured SiO(2)-based bone graft substitute. Human primary osteoblasts and the osteoblastic cell line, MG63, cultured on the SiO(2) biomatrix in monoculture retained their osteoblastic morphology and cellular functionality in vitro. The effect of the biomaterial in vivo and its vascularization potential was tested subcutaneously in Wistar rats and demonstrated both rapid vascularization and good integration within the peri-implant tissue. Scaffold degradation was progressive during the first month after implantation, with tartrate-resistant acid phosphatase-positive macrophages being …
Malignant transformation of the liver tumour precursor cell line OC/CDE 22 by the four stereoisomeric fjord region 3,4-dihydrodiol 1,2-epoxides of be…
1995
In previous work we established the rat liver oval cell line OC/CDE 22 in order to study in vitro mechanisms of liver cell transformation. We have now exposed OC/CDE 22 cells to each of the four optically active fjord region dihydrodiol epoxides of benzo[c]phenanthrene to investigate their capacity for malignant transformation of liver cells. All four configurational isomers, which are among the most potent carcinogenic metabolites of polycyclic aromatic hydrocarbons tested in murine tumour models, malignantly transform OC/CDE 22 cells at a 2 microM dose level, resulting in a similar colony-forming efficiency in soft agar. Inoculation of the transformed cells into newborn syngeneic rats pro…
Novel pathway in Bcr-Abl signal transduction involves Akt-independent, PLC-γ1-driven activation of mTOR/p70S6-kinase pathway
2009
In chronic myeloid leukemia, activation of the phosphoinositide 3-kinase (PI3K)/Akt pathway is crucial for survival and proliferation of leukemic cells. Essential downstream molecules involve mammalian target of rapamycin (mTOR) and S6-kinase. Here, we present a comprehensive analysis of the molecular events involved in activation of these key signaling pathways. We provide evidence for a previously unrecognized phospholipase C-gamma1 (PLC-gamma1)-controlled mechanism of mTOR/p70S6-kinase activation, which operates in parallel to the classical Akt-dependent machinery. Short-term imatinib treatment of Bcr-Abl-positive cells caused dephosphorylation of p70S6-K and S6-protein without inactivat…
The novel NF-κB inhibitor DHMEQ synergizes with celecoxib to exert antitumor effects on human liver cancer cells by a ROS-dependent mechanism
2012
In a previous work of ours dehydroxymethyl-epoxyquinomicin (DHMEQ), an inhibitor of NF-κB, was shown to induce apoptosis through Reactive Oxygen Species (ROS) production in hepatoma cells. The present study demonstrated that DHMEQ cooperates with Celecoxib (CLX) to decrease NF-κB DNA binding and to inhibit cell growth and proliferation more effectively than treatment with these single agents alone in the hepatoma cell lines HA22T/VGH and Huh-6. ROS production induced by the DHMEQ-CLX combination in turn generated the expression of genes involved in endoplasmic reticulum (ER) stress and silencing TRB3 mRNA significantly decreased DHMEQ-CLX-induced cell growth inhibition. Moreover, the DHMEQ-…
Downregulation of wild-type β-catenin expression by interleukin 6 in human hepatocarcinoma HepG2 cells: a possible role in the growth-regulatory effe…
2001
We investigated the antitumour effects of interleukin 6 (IL-6) on hepatocarcinoma HepG2 cells, endowed with high levels of a mutated, non-degradable, beta-catenin. IL-6 produced minimal growth-inhibitory effects and no apoptosis or gross changes in cell adhesion. Interestingly, however, it caused a consistent decrease in the cytoplasmic levels of wild-type, but not of mutated, beta-catenin protein. There was no effect on E-cadherin or gamma-catenin and a reduction in alpha-catenin occurred only at high concentrations. IL-4, a non-related cytokine, did not modify the content of beta-catenin. IL-6 did not influence beta-catenin mRNA levels. LiCl, a potent inhibitor of Glycogen Synthase Kinase…
Differences in the mechanisms of growth control in contact-inhibited and serum-deprived human fibroblasts
1997
In the present work we studied mechanisms of growth control in contact-inhibited and serum-deprived human diploid fibroblasts. The observation that the effects on [3H]thymidine incorporation and reduction of retinoblastoma gene product-phosphorylation were additive when contact-inhibition and serum-deprivation were combined led us to the conclusion that the underlying mechanisms might be different. Both contact-inhibition and serum-deprivation led to a strong decrease of cdk4-kinase-activity and cdk2-phosphorylation at Thr 160, while the total amounts of cdk4 and cdk2 remained constant. In contact-inhibited cells, we revealed a strong protein accumulation of the cdk2-inhibitor p27 and a sli…
Intrahippocampal transplantation of mesenchymal stromal cells promotes neuroplasticity
2012
Multipotent mesenchymal stromal cells (MSC) secrete soluble factors that stimulate the surrounding microenvironment. Such paracrine effects might underlie the potential benefits of many stem cell therapies. We tested the hypothesis that MSC are able to enhance intrinsic cellular plasticity in the adult rat hippocampus.Rat bone marrow-derived MSC were labeled with very small superparamagnetic iron oxide particles (VSOP), which allowed for non-invasive graft localization by magnetic resonance imaging (MRI). Moreover, MSC were transduced with lentiviral vectors to express the green fluorescent protein (GFP). The effects of bilateral MSC transplantation on hippocampal cellular plasticity were a…
Biological response of multicellular emt6 spheroids to exogenous lactate
1991
The influence of elevated lactate concentrations, as found in tumor microregions, on cellular growth, viability, and metabolic state was studied employing the multicellular spheroid model. Spheroids of EMT6/Ro cells were cultured at 37 degrees C in 5% or 20% (v/v) oxygen, using stirred media with various concentrations of exogenous lactate ranging from 0.0 mM (standard conditions) to 20.0 mM. Elevated concentrations of exogenous lactate led to a considerable decrease of the maximum spheroid diameter at growth saturation, e.g., for 20% O2 from around 1700 microns to 700 microns in 0.0 and 20.0 mM lactate respectively. Histological investigations showed that the thickness of the viable cell r…
Migration of renal carcinoma cells is dependent on protein kinase Cδ via β1 integrin and focal adhesion kinase
2008
Migration and adhesion of tumor cells are essential prerequisites for the formation of metastases in malignant diseases. Protein kinase C (PKC) has been shown to regulate cell migration, adhesion and proliferation. In order to identify a connection between PKC isoforms and tumor progression in renal cell carcinoma (RCC), the influence of PKC isoforms on cell migration, adhesion and proliferation and possible influences of the activity of integrins and focal adhesion kinase (FAK) were analyzed in RCC cells. The experiments were performed in the RCC cell line CCF-RC1 after pre-incubation of the cells with the PKC inhibitors GF109203X, GO6976, RO31-8220 and rottlerin. Cell migration and adhesi…