Complex interactions in EML cell stimulation by stem cell factor and IL-3

PubMed Central

Ye, Zhi-jia; Gulcicek, Erol; Stone, Kathryn; Lam, Tukiet; Schulz, Vincent; Weissman, Sherman M.

2011-01-01

Erythroid myeloid lymphoid (EML) cells are an established multipotent hematopoietic precursor cell line that can be maintained in medium including stem cell factor (SCF). EML cultures contain a heterogeneous mixture of cells, including a lineage-negative, CD34+ subset of cells that propagate rapidly in SCF and can clonally regenerate the mixed population. A second major subset of EML cells consists of lineage-negative. CD34− cells that can be propagated in IL-3 but grow slowly, if at all, in SCF, although they express the SCF receptor (c-kit). The response of these cells to IL-3 is stimulated synergistically by SCF, and we present evidence that both the synergy and the inhibition of c-kit responses may be mediated by direct interaction with IL-3 receptor. Further, the relative level of tyrosine phosphorylation of various substrates by either cytokine alone differs from that produced by the combination of the two cytokines, suggesting that cell signaling by the combination of the two cytokines differs from that produced by either alone. PMID:21383156

Discovery of survival factor for primitive chronic myeloid leukemia cells using induced pluripotent stem cells

PubMed Central

Suknuntha, Kran; Ishii, Yuki; Tao, Lihong; Hu, Kejin; McIntosh, Brian E.; Yang, David; Swanson, Scott; Stewart, Ron; Wang, Jean Y.J.; Thomson, James; Slukvin, Igor

2016-01-01

A definitive cure for chronic myeloid leukemia (CML) requires identifying novel therapeutic targets to eradicate leukemia stem cells (LSCs). However, the rarity of LSCs within the primitive hematopoietic cell compartment remains a major limiting factor for their study in humans. Here we show that primitive hematopoietic cells with typical LSC features, including adhesion defect, increased long-term survival and proliferation, and innate resistance to tyrosine kinase inhibitor (TKI) imatinib, can be generated de novo from reprogrammed primary CML cells. Using CML iPSC-derived primitive leukemia cells, we discovered olfactomedin 4 (OLFM4) as a novel factor that contributes to survival and growth of somatic lin−CD34+ cells from bone marrow of patients with CML in chronic phase, but not primitive hematopoietic cells from normal bone marrow. Overall, this study shows the feasibility and advantages of using reprogramming technology to develop strategies for targeting primitive leukemia cells. PMID:26561938

Plasma Cell Neoplasms (Including Multiple Myeloma) Treatment (PDQ®)—Patient Version

Cancer.gov

Plasma cell neoplasms occur when abnormal plasma cells or myeloma cells form tumors in the bones or soft tissues of the body. Multiple myeloma, plasmacytoma, lymphoplasmacytic lymphoma, and monoclonal gammopathy of undetermined significance (MGUS) are different types of plasma cell neoplasms. Find out about risk factors, symptoms, diagnostic tests, prognosis, and treatment for these diseases.

The dyad palindromic glutathione transferase P enhancer binds multiple factors including AP1.

PubMed Central

Diccianni, M B; Imagawa, M; Muramatsu, M

1992-01-01

Glutathione Transferase P (GST-P) gene expression is dominantly regulated by an upstream enhancer (GPEI) consisting of a dyad of palindromically oriented imperfect TPA (12-O-tetradecanoyl-phorbol-13-acetate)-responsive elements (TRE). GPEI is active in AP1-lacking F9 cells as well in AP1-containing HeLa cells. Despite GPEI's similarity to a TRE, c-jun co-transfection has only a minimal effect on transactivation. Antisense c-jun and c-fos co-transfection experiments further demonstrate the lack of a role for AP1 in GPEI mediated trans-activation in F9 cells, although endogenously present AP1 can influence GPEI in HeLa cells. Co-transfection of delta fosB with c-jun, which forms an inactive c-Jun/delta FosB heterodimer that binds TRE sequences, inhibits GPEI-mediated transcription in AP1-lacking F9 cells as well as AP1-containing HeLa cells. These data suggest novel factor(s) other than AP1 are influencing GPEI. Binding studies reveal multiple nucleoproteins bind to GPEI. These factors are likely responsible for the high level of GPEI-mediated transcription observed in the absence of AP1 and during hepatocarcinogenesis. Images PMID:1408831

The dyad palindromic glutathione transferase P enhancer binds multiple factors including AP1.

PubMed

Diccianni, M B; Imagawa, M; Muramatsu, M

1992-10-11

Glutathione Transferase P (GST-P) gene expression is dominantly regulated by an upstream enhancer (GPEI) consisting of a dyad of palindromically oriented imperfect TPA (12-O-tetradecanoyl-phorbol-13-acetate)-responsive elements (TRE). GPEI is active in AP1-lacking F9 cells as well in AP1-containing HeLa cells. Despite GPEI's similarity to a TRE, c-jun co-transfection has only a minimal effect on transactivation. Antisense c-jun and c-fos co-transfection experiments further demonstrate the lack of a role for AP1 in GPEI mediated trans-activation in F9 cells, although endogenously present AP1 can influence GPEI in HeLa cells. Co-transfection of delta fosB with c-jun, which forms an inactive c-Jun/delta FosB heterodimer that binds TRE sequences, inhibits GPEI-mediated transcription in AP1-lacking F9 cells as well as AP1-containing HeLa cells. These data suggest novel factor(s) other than AP1 are influencing GPEI. Binding studies reveal multiple nucleoproteins bind to GPEI. These factors are likely responsible for the high level of GPEI-mediated transcription observed in the absence of AP1 and during hepatocarcinogenesis.

Deficiency in the nuclear factor E2-related factor 2 renders pancreatic β-cells vulnerable to arsenic-induced cell damage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Bei; Department of Histology and Embryology, College of Basic Medical Sciences, China Medical University, Shenyang 110001; Fu, Jingqi

2012-11-01

Chronic human exposure to inorganic arsenic (iAs), a potent environmental oxidative stressor, is associated with increased prevalence of type 2 diabetes, where impairment of pancreatic β-cell function is a key pathogenic factor. Nuclear factor E2-related factor 2 (Nrf2) is a central transcription factor regulating cellular adaptive response to oxidative stress. However, persistent activation of Nrf2 in response to chronic oxidative stress, including inorganic arsenite (iAs{sup 3+}) exposure, blunts glucose-triggered reactive oxygen species (ROS) signaling and impairs glucose-stimulated insulin secretion (GSIS). In the current study, we found that MIN6 pancreatic β-cells with stable knockdown of Nrf2 (Nrf2-KD) by lentiviral shRNA andmore » pancreatic islets isolated from Nrf2-knockout (Nrf2−/−) mice exhibited reduced expression of several antioxidant and detoxification enzymes in response to acute iAs{sup 3+} exposure. As a result, Nrf2-KD MIN6 cells and Nrf2−/− islets were more susceptible to iAs{sup 3+} and monomethylarsonous acid (MMA{sup 3+})-induced cell damage, as measured by decreased cell viability, augmented apoptosis and morphological change. Pretreatment of MIN6 cells with Nrf2 activator tert-butylhydroquinone protected the cells from iAs{sup 3+}-induced cell damage in an Nrf2-dependent fashion. In contrast, antioxidant N‐acetyl cysteine protected Nrf2-KD MIN6 cells against acute cytotoxicity of iAs{sup 3+}. The present study demonstrates that Nrf2-mediated antioxidant response is critical in the pancreatic β-cell defense mechanism against acute cytotoxicity by arsenic. The findings here, combined with our previous results on the inhibitory effect of antioxidants on ROS signaling and GSIS, suggest that Nrf2 plays paradoxical roles in pancreatic β-cell dysfunction induced by environmental arsenic exposure. -- Highlights: ► Lack of Nrf2 reduced expression of antioxidant genes induced by iAs{sup 3+} in β-cells. ► Deficiency of Nrf2 in β-cells

Biology of Bone Tissue: Structure, Function, and Factors That Influence Bone Cells

PubMed Central

Florencio-Silva, Rinaldo; Sasso-Cerri, Estela; Simões, Manuel Jesus; Cerri, Paulo Sérgio

2015-01-01

Bone tissue is continuously remodeled through the concerted actions of bone cells, which include bone resorption by osteoclasts and bone formation by osteoblasts, whereas osteocytes act as mechanosensors and orchestrators of the bone remodeling process. This process is under the control of local (e.g., growth factors and cytokines) and systemic (e.g., calcitonin and estrogens) factors that all together contribute for bone homeostasis. An imbalance between bone resorption and formation can result in bone diseases including osteoporosis. Recently, it has been recognized that, during bone remodeling, there are an intricate communication among bone cells. For instance, the coupling from bone resorption to bone formation is achieved by interaction between osteoclasts and osteoblasts. Moreover, osteocytes produce factors that influence osteoblast and osteoclast activities, whereas osteocyte apoptosis is followed by osteoclastic bone resorption. The increasing knowledge about the structure and functions of bone cells contributed to a better understanding of bone biology. It has been suggested that there is a complex communication between bone cells and other organs, indicating the dynamic nature of bone tissue. In this review, we discuss the current data about the structure and functions of bone cells and the factors that influence bone remodeling. PMID:26247020

Factors affecting the development of somatic cell nuclear transfer embryos in Cattle.

PubMed

Akagi, Satoshi; Matsukawa, Kazutsugu; Takahashi, Seiya

2014-01-01

Nuclear transfer is a complex multistep procedure that includes oocyte maturation, cell cycle synchronization of donor cells, enucleation, cell fusion, oocyte activation and embryo culture. Therefore, many factors are believed to contribute to the success of embryo development following nuclear transfer. Numerous attempts to improve cloning efficiency have been conducted since the birth of the first sheep by somatic cell nuclear transfer. However, the efficiency of somatic cell cloning has remained low, and applications have been limited. In this review, we discuss some of the factors that affect the developmental ability of somatic cell nuclear transfer embryos in cattle.

Factors Affecting the Development of Somatic Cell Nuclear Transfer Embryos in Cattle

PubMed Central

AKAGI, Satoshi; MATSUKAWA, Kazutsugu; TAKAHASHI, Seiya

2014-01-01

Nuclear transfer is a complex multistep procedure that includes oocyte maturation, cell cycle synchronization of donor cells, enucleation, cell fusion, oocyte activation and embryo culture. Therefore, many factors are believed to contribute to the success of embryo development following nuclear transfer. Numerous attempts to improve cloning efficiency have been conducted since the birth of the first sheep by somatic cell nuclear transfer. However, the efficiency of somatic cell cloning has remained low, and applications have been limited. In this review, we discuss some of the factors that affect the developmental ability of somatic cell nuclear transfer embryos in cattle. PMID:25341701

Histiocyte-like cells expressing factor XIIIa do not belong to the neoplastic cell population in malignant fibrous histiocytoma.

PubMed

Szollosi, Zoltan; Nemeth, Tamas; Egervari, Kristof; Nemes, Zoltan

2005-01-01

The term malignant fibrous histiocytoma (MFH) is widely used for pleomorphic soft tissue sarcomas without a specific line of differentiation. MFH is included in the category of fibrohistiocytic soft tissue tumors. MFH has a broad range of histological appearances, and it has several subtypes. All of these subtypes are composed of spindled fibroblast-like cells, undifferentiated cells, and histiocytic or histiocyte-like cells. A large number of fibroblast-like and pleomorphic cells express factor XIIIa in MFH. The cytological pleomorphism of factor XIIIa cells suggests that these cells may belong to the neoplastic population. It is equally possible that the factor XIIIa-positive cells are only activated stromal cells. The relation of factor XIIIa-positive cells to the neoplastic cell population in MFH is addressed in the present study. A morphometric approach compares the measure of nuclear pleomorphism of the factor XIIIa-positive cells with that of the factor XIIIa-negative tumor cells in high-grade MFH. The immunohistochemical approach compares the factor XIIIa-positive and -negative cell populations with regard to mutations of p53 tumor suppressor gene in p53-positive MFH cases. We selected 58 cases of soft tissue pleomorphic or storiform-pleomorphic MFH on the basis of histopathological examinations. A combination of incident light immunofluorescence for factor XIIIa and transmitted light examination for nuclear staining was used for morphometrical analysis. We found cytoplasmic factor XIIIa positivity in at least 2% of cells in 39 cases; the number of factor XIIIa-positive cells was under 0.5% in two cases, and the number of factor-positive cells ranged between 0.5% and 2% in 13 cases. Eighteen cases were analyzed with nuclear morphometry. We found that mean nuclear area and mean nuclear Ferret diameter in factor XIIIa-positive cells differed significantly from those of the tumor cells in all cases. The mean nuclear roundness factor differed significantly only

Trophic factors from adipose tissue-derived multi-lineage progenitor cells promote cytodifferentiation of periodontal ligament cells.

PubMed

Sawada, Keigo; Takedachi, Masahide; Yamamoto, Satomi; Morimoto, Chiaki; Ozasa, Masao; Iwayama, Tomoaki; Lee, Chun Man; Okura, Hanayuki; Matsuyama, Akifumi; Kitamura, Masahiro; Murakami, Shinya

2015-08-14

Stem and progenitor cells are currently being investigated for their applicability in cell-based therapy for periodontal tissue regeneration. We recently demonstrated that the transplantation of adipose tissue-derived multi-lineage progenitor cells (ADMPCs) enhances periodontal tissue regeneration in beagle dogs. However, the molecular mechanisms by which transplanted ADMPCs induce periodontal tissue regeneration remain to be elucidated. In this study, trophic factors released by ADMPCs were examined for their paracrine effects on human periodontal ligament cell (HPDL) function. ADMPC conditioned medium (ADMPC-CM) up-regulated osteoblastic gene expression, alkaline phosphatase activity and calcified nodule formation in HPDLs, but did not significantly affect their proliferative response. ADMPCs secreted a number of growth factors, including insulin-like growth factor binding protein 6 (IGFBP6), hepatocyte growth factor and vascular endothelial growth factor. Among these, IGFBP6 was most highly expressed. Interestingly, the positive effects of ADMPC-CM on HPDL differentiation were significantly suppressed by transfecting ADMPCs with IGFBP6 siRNA. Our results suggest that ADMPCs transplanted into a defect in periodontal tissue release trophic factors that can stimulate the differentiation of HPDLs to mineralized tissue-forming cells, such as osteoblasts and cementoblasts. IGFBP6 may play crucial roles in ADMPC-induced periodontal regeneration. Copyright © 2015 Elsevier Inc. All rights reserved.

Cell Proliferation and Epidermal Growth Factor Signaling in Non-small Cell Lung Adenocarcinoma Cell Lines Are Dependent on Rin1

PubMed Central

Tomshine, Jin C.; Severson, Sandra R.; Wigle, Dennis A.; Sun, Zhifu; Beleford, Daniah A. T.; Shridhar, Vijayalakshmi; Horazdovsky, Bruce F.

2009-01-01

Rin1 is a Rab5 guanine nucleotide exchange factor that plays an important role in Ras-activated endocytosis and growth factor receptor trafficking in fibroblasts. In this study, we show that Rin1 is expressed at high levels in a large number of non-small cell lung adenocarcinoma cell lines, including Hop62, H650, HCC4006, HCC827, EKVX, HCC2935, and A549. Rin1 depletion from A549 cells resulted in a decrease in cell proliferation that was correlated to a decrease in epidermal growth factor receptor (EGFR) signaling. Expression of wild type Rin1 but not the Rab5 guanine nucleotide exchange factor-deficient Rin1 (Rin1Δ) complemented the Rin1 depletion effects, and overexpression of Rin1Δ had a dominant negative effect on cell proliferation. Rin1 depletion stabilized the cell surface levels of EGFR, suggesting that internalization was necessary for robust signaling in A549 cells. In support of this conclusion, introduction of either dominant negative Rab5 or dominant negative dynamin decreased A549 proliferation and EGFR signaling. These data demonstrate that proper internalization and endocytic trafficking are critical for EGFR-mediated signaling in A549 cells and suggest that up-regulation of Rin1 in A549 cell lines may contribute to their proliferative nature. PMID:19570984

B cell helper factors. II. Synergy among three helper factors in the response of T cell- and macrophage-depleted B cells.

PubMed

Liebson, H J; Marrack, P; Kappler, J

1982-10-01

The concanavalin A- (Con A) stimulated supernatant of normal spleen cells (normal Con A SN) was shown to contain a set of helper factors sufficient to allow T cell- and macrophage- (M phi) depleted murine splenic B cells to produce a plaque-forming cell response to the antigen sheep red blood cells (SRBC). The activity of normal Con A SN could be reconstituted by a mixture of three helper factor preparations. The first was the interleukin 2- (IL 2) containing Con A SN of the T cell hybridoma, FS6-14.13. The second was a normal Con A SN depleted of IL 2 by extended culture with T cell blasts from which the 30,000 to 50,000 m.w. factors were isolated (interleukin X, IL X). The third was a SN either from the M phi tumor cell line P388D1 or from normal M phi taken from Corynebacterium parvum-immune mice. The combination of all three helper factor preparations was required to equal the activity of normal Con A SN; however, the M phi SN had the least overall effect. The M phi SN and IL 2 had to be added at the initiation of the culture period for a maximal effect, but the IL X preparation was most effective when added 24 hr after the initiation of culture. These results indicate that at least three nonspecific helper factors contribute to the helper activity in normal Con A SN.

Soluble factor(s) from bone marrow cells can rescue lethally irradiated mice by protecting endogenous hematopoietic stem cells.

PubMed

Zhao, Yi; Zhan, Yuxia; Burke, Kathleen A; Anderson, W French

2005-04-01

Ionizing radiation-induced myeloablation can be rescued via bone marrow transplantation (BMT) or administration of cytokines if given within 2 hours after radiation exposure. There is no evidence for the existence of soluble factors that can rescue an animal after a lethal dose of radiation when administered several hours postradiation. We established a system that could test the possibility for the existence of soluble factors that could be used more than 2 hours postirradiation to rescue animals. Animals with an implanted TheraCyte immunoisolation device (TID) received lethal-dose radiation and then normal bone marrow Lin- cells were loaded into the device (thereby preventing direct interaction between donor and recipient cells). Animal survival was evaluated and stem cell activity was tested with secondary bone marrow transplantation and flow cytometry analysis. Donor cell gene expression of five antiapoptotic cytokines was examined. Bone marrow Lin- cells rescued lethally irradiated animals via soluble factor(s). Bone marrow cells from the rescued animals can rescue and repopulate secondary lethally irradiated animals. Within the first 6 hours post-lethal-dose radiation, there is no significant change of gene expression of the known radioprotective factors TPO, SCF, IL-3, Flt-3 ligand, and SDF-1. Hematopoietic stem cells can be protected in lethally irradiated animals by soluble factors produced by bone marrow Lin- cells.

Hemoglobin enhances tissue factor expression on human malignant cells.

PubMed

Siddiqui, F A; Amirkhosravi, A; Amaya, M; Meyer, T; Biggerstaff, J; Desai, H; Francis, J L

2001-04-01

Tissue Factor (TF) is a transmembrane glycoprotein that complexes with factor VII/activated factor VII to initiate blood coagulation. TF may be expressed on the surface of various cells including monocytes and endothelial cells. Over-expression of TF in human tumor cell lines promotes metastasis. We recently showed that hemoglobin (Hb) forms a specific complex with TF purified from human malignant melanoma cells and enhances its procoagulant activity (PCA). To further study this interaction, we examined the effect of Hb on the expression of TF on human malignant (TF+) cells and KG1 myeloid leukemia (TF-) cells. Human melanoma A375 and J82 bladder carcinoma cells, which express TF at moderate and relatively high levels, respectively, were incubated with varying concentrations (0-1.5 mg/ml) of Hb. After washing, cells were analyzed for Hb binding and TF expression using flow cytometry and confocal microscopy. Hb bound to the cells in a concentration-dependent manner, and increased both TF expression and PCA. The human A375 malignant melanoma cells incubated with Hb (1 mg/ml) expressed up to six times more TF antigen than cells without Hb. This increase in TF expression and PCA of intact cells incubated with Hb was significantly inhibited by cycloheximide at a concentration of 10 microg/ml (P < 0.01). An increase in total cellular TF antigen content was demonstrated by specific immunoassay. In contrast, Hb (5 mg/ml) did not induce TF expression and PCA on KG1 cells as determined by flow cytometry and TF (FXAA) activity. We conclude that Hb specifically binds to TF-bearing malignant cells and increases their PCA. This effect seems to be at least partly due to de novo synthesis of TF and increased surface expression. However, the exact mechanism by which Hb binds and upregulates TF expression remains to be determined.

Electrolytes including fluorinated solvents for use in electrochemical cells

DOEpatents

Tikhonov, Konstantin; Yip, Ka Ki; Lin, Tzu-Yuan

2015-07-07

Provided are electrochemical cells and electrolytes used to build such cells. The electrolytes include ion-supplying salts and fluorinated solvents capable of maintaining single phase solutions with the salts at between about -30.degree. C. to about 80.degree. C. The fluorinated solvents, such as fluorinated carbonates, fluorinated esters, and fluorinated esters, are less flammable than their non-fluorinated counterparts and increase safety characteristics of cells containing these solvents. The amount of fluorinated solvents in electrolytes may be between about 30% and 80% by weight not accounting weight of the salts. Fluorinated salts, such as fluoroalkyl-substituted LiPF.sub.6, fluoroalkyl-substituted LiBF.sub.4 salts, linear and cyclic imide salts as well as methide salts including fluorinated alkyl groups, may be used due to their solubility in the fluorinated solvents. In some embodiments, the electrolyte may also include a flame retardant, such as a phosphazene or, more specifically, a cyclic phosphazene and/or one or more ionic liquids.

Various types of stem cells, including a population of very small embryonic-like stem cells, are mobilized into peripheral blood in patients with Crohn's disease.

PubMed

Marlicz, Wojciech; Zuba-Surma, Ewa; Kucia, Magda; Blogowski, Wojciech; Starzynska, Teresa; Ratajczak, Mariusz Z

2012-09-01

Developmentally early cells, including hematopoietic stem progenitor cells (HSPCs), mesenchymal stem cells (MSCs), endothelial progenitor cells (EPCs), and very small embryonic-like stem cells (VSELs), are mobilized into peripheral blood (PB) in response to tissue/organ injury. We sought to determine whether these cells are mobilized into PB in patients with Crohn's disease (CD). Twenty-five patients with active CD, 20 patients in clinical remission, and 25 age-matched controls were recruited and PB samples harvested. The circulating CD133+/Lin-/CD45+ and CD34+/Lin-/CD45+ cells enriched for HSPCs, CD105+/STRO-1+/CD45- cells enriched for MSCs, CD34+/KDR+/CD31+/CD45-cells enriched for EPCs, and small CXCR4+CD34+CD133+ subsets of Lin-CD45- cells that correspond to the population of VSELs were counted by fluorescence-activated cell sorting (FACS) and evaluated by direct immunofluorescence staining for pluripotency embryonic markers and by reverse-transcription polymerase chain reaction (RT-PCR) for expression of messenger (m)RNAs for a panel of genes expressed in intestine epithelial stem cells. The serum concentration of factors involved in stem cell trafficking, such as stromal derived factor-1 (SDF-1), vascular endothelial growth factor (VEGF), and hepatocyte growth factor (HGF) were measured by enzyme-linked immunosorbent assay (ELISA). Our data indicate that cells expressing markers for MSCs, EPCs, and small Oct-4+Nanog+SSEA-4+CXCR4+lin-CD45- VSELs are mobilized into PB in CD. The mobilized cells also expressed at the mRNA level genes playing a role in development and regeneration of gastrointestinal epithelium. All these changes were accompanied by increased serum concentrations of VEGF and HGF. CD triggers the mobilization of MSCs, EPCs, and VSELs, while the significance and precise role of these mobilized cells in repair of damaged intestine requires further study. Copyright © 2012 Crohn's & Colitis Foundation of America, Inc.

Distinct speed dependence of entorhinal island and ocean cells, including respective grid cells

PubMed Central

Sun, Chen; Kitamura, Takashi; Yamamoto, Jun; Martin, Jared; Pignatelli, Michele; Kitch, Lacey J.; Schnitzer, Mark J.; Tonegawa, Susumu

2015-01-01

Entorhinal–hippocampal circuits in the mammalian brain are crucial for an animal’s spatial and episodic experience, but the neural basis for different spatial computations remain unknown. Medial entorhinal cortex layer II contains pyramidal island and stellate ocean cells. Here, we performed cell type-specific Ca2+ imaging in freely exploring mice using cellular markers and a miniature head-mounted fluorescence microscope. We found that both oceans and islands contain grid cells in similar proportions, but island cell activity, including activity in a proportion of grid cells, is significantly more speed modulated than ocean cell activity. We speculate that this differential property reflects island cells’ and ocean cells’ contribution to different downstream functions: island cells may contribute more to spatial path integration, whereas ocean cells may facilitate contextual representation in downstream circuits. PMID:26170279

TCPs, WUSs, and WINDs: families of transcription factors that regulate shoot meristem formation, stem cell maintenance, and somatic cell differentiation.

PubMed

Ikeda, Miho; Ohme-Takagi, Masaru

2014-01-01

In contrast to somatic mammalian cells, which cannot alter their fate, plant cells can dedifferentiate to form totipotent callus cells and regenerate a whole plant, following treatment with specific phytohormones. However, the regulatory mechanisms and key factors that control differentiation-dedifferentiation and cell totipotency have not been completely clarified in plants. Recently, several plant transcription factors that regulate meristem formation and dedifferentiation have been identified and include members of the TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTOR (TCP), WUSCHEL (WUS), and WOUND INDUCED DEDIFFERENTIATION (WIND1) families. WUS and WIND positively control plant cell totipotency, while TCP negatively controls it. Interestingly, TCP is a transcriptional activator that acts as a negative regulator of shoot meristem formation, and WUS is a transcriptional repressor that positively maintains totipotency of the stem cells of the shoot meristem. We describe here the functions of TCP, WUS, and WIND transcription factors in the regulation of differentiation-dedifferentiation by positive and negative transcriptional regulators.

HGF/scatter factor selectively promotes cell invasion by increasing integrin avidity.

PubMed

Trusolino, L; Cavassa, S; Angelini, P; Andó, M; Bertotti, A; Comoglio, P M; Boccaccio, C

2000-08-01

Hepatocyte growth factor/scatter factor (HGF/SF) controls a genetic program known as 'invasive growth', which involves as critical steps cell adhesion, migration, and trespassing of basement membranes. We show here that in MDA-MB-231 carcinoma cells, these steps are elicited by HGF/SF but not by epidermal growth factor (EGF). Neither factor substantially alters the production or activity of extracellular matrix proteases. HGF/SF, but not EGF, selectively promotes cell adhesion on laminins 1 and 5, fibronectin, and vitronectin through a PI3-K-dependent mechanism. Increased adhesion is followed by enhanced invasiveness through isolated matrix proteins as well as through reconstituted basement membranes. Inhibition assays using function-blocking antibodies show that this phenomenon is mediated by multiple integrins including beta1, beta3, beta4, and beta5. HGF/SF triggers clustering of all these integrins at actin-rich adhesive sites and lamellipodia but does not quantitatively modify their membrane expression. These data suggest that HGF/SF promotes cell adhesion and invasiveness by increasing the avidity of integrins for their specific ligands.

Epidemiologic characteristics and risk factors for renal cell cancer

PubMed Central

Lipworth, Loren; Tarone, Robert E; Lund, Lars; McLaughlin, Joseph K

2009-01-01

Incidence rates of renal cell cancer, which accounts for 85% of kidney cancers, have been rising in the United States and in most European countries for several decades. Family history is associated with a two- to four-fold increase in risk, but the major forms of inherited predisposition together account for less than 4% of renal cell cancers. Cigarette smoking, obesity, and hypertension are the most consistently established risk factors. Analgesics have not been convincingly linked with renal cell cancer risk. A reduced risk of renal cell cancer among statin users has been hypothesized but has not been adequately studied. A possible protective effect of fruit and vegetable consumption is the only moderately consistently reported dietary finding, and, with the exception of a positive association with parity, evidence for a role of hormonal or reproductive factors in the etiology of renal cell cancer in humans is limited. A recent hypothesis that moderate levels of alcohol consumption may be protective for renal cell cancer is not strongly supported by epidemiologic results, which are inconsistent with respect to the categories of alcohol consumption and the amount of alcohol intake reportedly associated with decreased risk. For occupational factors, the weight of the evidence does not provide consistent support for the hypotheses that renal cell cancer may be caused by asbestos, gasoline, or trichloroethylene exposure. The established determinants of renal cell cancer, cigarette smoking, obesity, and hypertension, account for less than half of these cancers. Novel epidemiologic approaches, including evaluation of gene–environment interactions and epigenetic mechanisms of inherited and acquired increased risk, are needed to explain the increasing incidence of renal cell cancer. PMID:20865085

The Host Range of Gammaretroviruses and Gammaretroviral Vectors Includes Post-Mitotic Neural Cells

PubMed Central

Liu, Xiu-Huai; Xu, Wenqin; Russ, Jill; Eiden, Lee E.; Eiden, Maribeth V.

2011-01-01

Background Gammaretroviruses and gammaretroviral vectors, in contrast to lentiviruses and lentiviral vectors, are reported to be restricted in their ability to infect growth-arrested cells. The block to this restriction has never been clearly defined. The original assessment of the inability of gammaretroviruses and gammaretroviral vectors to infect growth-arrested cells was carried out using established cell lines that had been growth-arrested by chemical means, and has been generalized to neurons, which are post-mitotic. We re-examined the capability of gammaretroviruses and their derived vectors to efficiently infect terminally differentiated neuroendocrine cells and primary cortical neurons, a target of both experimental and therapeutic interest. Methodology/Principal Findings Using GFP expression as a marker for infection, we determined that both growth-arrested (NGF-differentiated) rat pheochromocytoma cells (PC12 cells) and primary rat cortical neurons could be efficiently transduced, and maintained long-term protein expression, after exposure to murine leukemia virus (MLV) and MLV-based retroviral vectors. Terminally differentiated PC12 cells transduced with a gammaretroviral vector encoding the anti-apoptotic protein Bcl-xL were protected from cell death induced by withdrawal of nerve growth factor (NGF), demonstrating gammaretroviral vector-mediated delivery and expression of genes at levels sufficient for therapeutic effect in non-dividing cells. Post-mitotic rat cortical neurons were also shown to be susceptible to transduction by murine replication-competent gammaretroviruses and gammaretroviral vectors. Conclusions/Significance These findings suggest that the host range of gammaretroviruses includes post-mitotic and other growth-arrested cells in mammals, and have implications for re-direction of gammaretroviral gene therapy to neurological disease. PMID:21464894

Associations between environmental factors and hospital admissions for sickle cell disease

PubMed Central

Piel, Frédéric B.; Tewari, Sanjay; Brousse, Valentine; Analitis, Antonis; Font, Anna; Menzel, Stephan; Chakravorty, Subarna; Thein, Swee Lay; Inusa, Baba; Telfer, Paul; de Montalembert, Mariane; Fuller, Gary W.; Katsouyanni, Klea; Rees, David C.

2017-01-01

Sickle cell disease is an increasing global health burden. This inherited disease is characterized by a remarkable phenotypic heterogeneity, which can only partly be explained by genetic factors. Environmental factors are likely to play an important role but studies of their impact on disease severity are limited and their results are often inconsistent. This study investigated associations between a range of environmental factors and hospital admissions of young patients with sickle cell disease in London and in Paris between 2008 and 2012. Specific analyses were conducted for subgroups of patients with different genotypes and for the main reasons for admissions. Generalized additive models and distributed lag non-linear models were used to assess the magnitude of the associations and to calculate relative risks. Some environmental factors significantly influence the numbers of hospital admissions of children with sickle cell disease, although the associations identified are complicated. Our study suggests that meteorological factors are more likely to be associated with hospital admissions for sickle cell disease than air pollutants. It confirms previous reports of risks associated with wind speed (risk ratio: 1.06/standard deviation; 95% confidence interval: 1.00–1.12) and also with rainfall (1.06/standard deviation; 95% confidence interval: 1.01–1.12). Maximum atmospheric pressure was found to be a protective factor (0.93/standard deviation; 95% confidence interval: 0.88–0.99). Weak or no associations were found with temperature. Divergent associations were identified for different genotypes or reasons for admissions, which could partly explain the lack of consistency in earlier studies. Advice to patients with sickle cell disease usually includes avoiding a range of environmental conditions that are believed to trigger acute complications, including extreme temperatures and high altitudes. Scientific evidence to support such advice is limited and

Associations between environmental factors and hospital admissions for sickle cell disease.

PubMed

Piel, Frédéric B; Tewari, Sanjay; Brousse, Valentine; Analitis, Antonis; Font, Anna; Menzel, Stephan; Chakravorty, Subarna; Thein, Swee Lay; Inusa, Baba; Telfer, Paul; de Montalembert, Mariane; Fuller, Gary W; Katsouyanni, Klea; Rees, David C

2017-04-01

Sickle cell disease is an increasing global health burden. This inherited disease is characterized by a remarkable phenotypic heterogeneity, which can only partly be explained by genetic factors. Environmental factors are likely to play an important role but studies of their impact on disease severity are limited and their results are often inconsistent. This study investigated associations between a range of environmental factors and hospital admissions of young patients with sickle cell disease in London and in Paris between 2008 and 2012. Specific analyses were conducted for subgroups of patients with different genotypes and for the main reasons for admissions. Generalized additive models and distributed lag non-linear models were used to assess the magnitude of the associations and to calculate relative risks. Some environmental factors significantly influence the numbers of hospital admissions of children with sickle cell disease, although the associations identified are complicated. Our study suggests that meteorological factors are more likely to be associated with hospital admissions for sickle cell disease than air pollutants. It confirms previous reports of risks associated with wind speed (risk ratio: 1.06/standard deviation; 95% confidence interval: 1.00-1.12) and also with rainfall (1.06/standard deviation; 95% confidence interval: 1.01-1.12). Maximum atmospheric pressure was found to be a protective factor (0.93/standard deviation; 95% confidence interval: 0.88-0.99). Weak or no associations were found with temperature. Divergent associations were identified for different genotypes or reasons for admissions, which could partly explain the lack of consistency in earlier studies. Advice to patients with sickle cell disease usually includes avoiding a range of environmental conditions that are believed to trigger acute complications, including extreme temperatures and high altitudes. Scientific evidence to support such advice is limited and sometimes

Hypoxia-inducible factor regulates alphavbeta3 integrin cell surface expression.

PubMed

Cowden Dahl, Karen D; Robertson, Sarah E; Weaver, Valerie M; Simon, M Celeste

2005-04-01

Hypoxia-inducible factor (HIF)-deficient placentas exhibit a number of defects, including changes in cell fate adoption, lack of fetal angiogenesis, hypocellularity, and poor invasion into maternal tissue. HIF is a heterodimeric transcription factor consisting of alpha and beta aryl hydrocarbon receptor nuclear translocator or ARNT) subunits. We used undifferentiated trophoblast stem (TS) cells to characterize HIF-dependent adhesion, migration, and invasion. Arnt(-/-) and Hifalpha(-/-) TS cells exhibit reduced adhesion and migration toward vitronectin compared with wild-type cells. Furthermore, this defect is associated with decreased cell surface expression of integrin alphavbeta3 and significantly decreased expression of this integrin in focal adhesions. Because of the importance of adhesion and migration in tumor progression (in addition to placental development), we examined the affect of culturing B16F0 melanoma cells in 1.5% oxygen (O(2)). Culturing B16F0 melanoma cells at 1.5% O(2) resulted in increased alphavbeta3 integrin surface expression and increased adhesion to and migration toward vitronectin. Together, these data suggest that HIF and O(2) tension influence placental invasion and tumor migration by increasing cell surface expression of alphavbeta3 integrin.

Industrial production of clotting factors: Challenges of expression, and choice of host cells.

PubMed

Kumar, Sampath R

2015-07-01

The development of recombinant forms of blood coagulation factors as safer alternatives to plasma derived factors marked a major advance in the treatment of common coagulation disorders. These are complex proteins, mostly enzymes or co-enzymes, involving multiple post-translational modifications, and therefore are difficult to express. This article reviews the nature of the expression challenges for the industrial production of these factors, vis-à-vis the translational and post-translational bottlenecks, as well as the choice of host cell lines for high-fidelity production. For achieving high productivities of vitamin K dependent proteins, which include factors II (prothrombin), VII, IX and X, and protein C, host cell limitation of γ-glutamyl carboxylation is a major bottleneck. Despite progress in addressing this, involvement of yet unidentified protein(s) impedes a complete cell engineering solution. Human factor VIII expresses at very low levels due to limitations at several steps in the protein secretion pathway. Protein and cell engineering, vector improvement and alternate host cells promise improvement in the productivity. Production of Von Willebrand factor is constrained by its large size, complex structure, and the need for extensive glycosylation and disulfide-bonded oligomerization. All the licensed therapeutic factors are produced in CHO, BHK or HEK293 cells. While HEK293 is a recent adoption, BHK cells appear to be disfavored. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Plasma Cell Neoplasms (Including Multiple Myeloma)—Health Professional Version

Cancer.gov

There are several types of plasma cell neoplasms, including monoclonal gammopathy of undetermined significance (MGUS), isolated plasmacytoma of the bone, extramedullary plasmacytoma, and multiple myeloma. Find evidence-based information on plasma cell neoplasms treatment, research, and statistics.

DNA Damage Response Factors from Diverse Pathways, Including DNA Crosslink Repair, Mediate Alternative End Joining

PubMed Central

Howard, Sean M.; Yanez, Diana A.; Stark, Jeremy M.

2015-01-01

Alternative end joining (Alt-EJ) chromosomal break repair involves bypassing classical non-homologous end joining (c-NHEJ), and such repair causes mutations often with microhomology at the repair junction. Since the mediators of Alt-EJ are not well understood, we have sought to identify DNA damage response (DDR) factors important for this repair event. Using chromosomal break reporter assays, we surveyed an RNAi library targeting known DDR factors for siRNAs that cause a specific decrease in Alt-EJ, relative to an EJ event that is a composite of Alt-EJ and c-NHEJ (Distal-EJ between two tandem breaks). From this analysis, we identified several DDR factors that are specifically important for Alt-EJ relative to Distal-EJ. While these factors are from diverse pathways, we also found that most of them also promote homologous recombination (HR), including factors important for DNA crosslink repair, such as the Fanconi Anemia factor, FANCA. Since bypass of c-NHEJ is likely important for both Alt-EJ and HR, we disrupted the c-NHEJ factor Ku70 in Fanca-deficient mouse cells and found that Ku70 loss significantly diminishes the influence of Fanca on Alt-EJ. In contrast, an inhibitor of poly ADP-ribose polymerase (PARP) causes a decrease in Alt-EJ that is enhanced by Ku70 loss. Additionally, the helicase/nuclease DNA2 appears to have distinct effects from FANCA and PARP on both Alt-EJ, as well as end resection. Finally, we found that the proteasome inhibitor Bortezomib, a cancer therapeutic that has been shown to disrupt FANC signaling, causes a significant reduction in both Alt-EJ and HR, relative to Distal-EJ, as well as a substantial loss of end resection. We suggest that several distinct DDR functions are important for Alt-EJ, which include promoting bypass of c-NHEJ and end resection. PMID:25629353

Th17 cell-mediated immune responses promote mast cell proliferation by triggering stem cell factor in keratinocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cho, Kyung-Ah; Park, Minhwa; Kim, Yu-Hee

Although mast cells are traditionally thought to function as effector cells in allergic responses, they have increasingly been recognized as important regulators of various immune responses. Mast cells mature locally; thus, tissue-specific influences are important for promoting mast cell accumulation and survival in the skin and the gastrointestinal tract. In this study, we determined the effects of keratinocytes on mast cell accumulation during Th17-mediated skin inflammation. We observed increases in dermal mast cells in imiquimod-induced psoriatic dermatitis in mice accompanied by the expression of epidermal stem cell factor (SCF), a critical mast cell growth factor. Similar to mouse epidermal keratinocytes,more » SCF was highly expressed in the human HaCaT keratinocyte cell line following stimulation with IL−17. Further, keratinocytes promoted mast cell proliferation following stimulation with IL−17 in vitro. However, the effects of keratinocytes on mast cells were significantly diminished in the presence of anti−CD117 (stem cell factor receptor) blocking antibodies. Taken together, our results revealed that the Th17-mediated inflammatory environment promotes mast cell accumulation through keratinocyte-derived SCF. - Highlights: • Psoriasis-like skin inflammation increase dermal mast cells. • Keratinocyte produce stem cell factor in psoriasis-like skin inflammation. • Keratinocyte promote mast cell proliferation by stem cell factor dependent manner.« less

Preliminary investigations on the effects of a Strongylus vulgaris larval extract, mononuclear factors and platelet factors on equine smooth muscle cells in vitro.

PubMed

Morgan, S J; Storts, R W; Stromberg, P C; Sowa, B A; Lay, J C

1989-01-01

Factors involved in the proliferation of equine vascular smooth muscle cells were studied in vitro. The most prominent proliferative responses in cultured vascular smooth muscle cells were induced by Strongylus vulgaris larval antigen extract (LAE) and platelet-derived factors. Less significant proliferative responses were obtained with conditioned media from S. vulgaris LAE stimulated and from unstimulated equine mononuclear leukocytes. Additionally, vascular smooth muscle cells exposed to S. vulgaris LAE developed numerous perinuclear vacuoles and were more spindle-shaped than control or smooth muscle cells exposed to other factors. Equine mononuclear leukocytes exposed to LAE developed prominent morphological changes, including enlargement, clumping and increased numbers of mitotic figures.

Fever in trauma patients: evaluation of risk factors, including traumatic brain injury.

PubMed

Bengualid, Victoria; Talari, Goutham; Rubin, David; Albaeni, Aiham; Ciubotaru, Ronald L; Berger, Judith

2015-03-01

The role of fever in trauma patients remains unclear. Fever occurs as a response to release of cytokines and prostaglandins by white blood cells. Many factors, including trauma, can trigger release of these factors. To determine whether (1) fever in the first 48 hours is related to a favorable outcome in trauma patients and (2) fever is more common in patients with head trauma. Retrospective study of trauma patients admitted to the intensive care unit for at least 2 days. Data were analyzed by using multivariate analysis. Of 162 patients studied, 40% had fever during the first 48 hours. Febrile patients had higher mortality rates than did afebrile patients. When adjusted for severity of injuries, fever did not correlate with mortality. Neither the incidence of fever in the first 48 hours after admission to the intensive care unit nor the number of days febrile in the unit differed between patients with and patients without head trauma (traumatic brain injury). About 70% of febrile patients did not have a source found for their fever. Febrile patients without an identified source of infection had lower peak white blood cell counts, lower maximum body temperature, and higher minimum platelet counts than did febrile patients who had an infectious source identified. The most common infection was pneumonia. No relationship was found between the presence of fever during the first 48 hours and mortality. Patients with traumatic brain injury did not have a higher incidence of fever than did patients without traumatic brain injury. About 30% of febrile patients had an identifiable source of infection. Further studies are needed to understand the origin and role of fever in trauma patients. ©2015 American Association of Critical-Care Nurses.

Protective Role of Nuclear Factor E2-Related Factor 2 against Acute Oxidative Stress-Induced Pancreatic β-Cell Damage

PubMed Central

Fu, Jingqi; Zheng, Hongzhi; Wang, Huihui; Yang, Bei; Zhao, Rui; Lu, Chunwei; Liu, Zhiyuan; Hou, Yongyong; Xu, Yuanyuan; Zhang, Qiang; Qu, Weidong; Pi, Jingbo

2015-01-01

Oxidative stress is implicated in the pathogenesis of pancreatic β-cell dysfunction that occurs in both type 1 and type 2 diabetes. Nuclear factor E2-related factor 2 (NRF2) is a master regulator in the cellular adaptive response to oxidative stress. The present study found that MIN6 β-cells with stable knockdown of Nrf2 (Nrf2-KD) and islets isolated from Nrf2-knockout mice expressed substantially reduced levels of antioxidant enzymes in response to a variety of stressors. In scramble MIN6 cells or wild-type islets, acute exposure to oxidative stressors, including hydrogen peroxide (H2O2) and S-nitroso-N-acetylpenicillamine, resulted in cell damage as determined by decrease in cell viability, reduced ATP content, morphology changes of islets, and/or alterations of apoptotic biomarkers in a concentration- and/or time-dependent manner. In contrast, silencing of Nrf2 sensitized MIN6 cells or islets to the damage. In addition, pretreatment of MIN6 β-cells with NRF2 activators, including CDDO-Im, dimethyl fumarate (DMF), and tert-butylhydroquinone (tBHQ), protected the cells from high levels of H2O2-induced cell damage. Given that reactive oxygen species (ROS) are involved in regulating glucose-stimulated insulin secretion (GSIS) and persistent activation of NRF2 blunts glucose-triggered ROS signaling and GSIS, the present study highlights the distinct roles that NRF2 may play in pancreatic β-cell dysfunction that occurs in different stages of diabetes. PMID:25949772

An increase in circulating B cell-activating factor in childhood-onset ocular myasthenia gravis.

PubMed

Motobayashi, Mitsuo; Inaba, Yuji; Nishimura, Takafumi; Kobayashi, Norimoto; Nakazawa, Yozo; Koike, Kenichi

2015-04-01

Myasthenia gravis is a B cell-mediated autoimmune disorder. The pathophysiology of childhood-onset ocular myasthenia gravis remains unclear. We investigated serum B cell-activating factor levels and other immunological parameters in child patients with ocular myasthenia gravis. Blood samples were obtained from 9 children with ocular myasthenia gravis and 20 age-matched controls. We assayed serum concentrations of B cell-activating factor, anti-acetylcholine receptor antibody titers, 7 types of cytokines (interleukins-2, -4, -6, -10, and -17A; interferon-γ; tumor necrosis factor-α) as well as the percentages of peripheral blood CD4+, CD8+, and CD19+ cells. Serum B cell-activating factor levels were significantly higher before immunosuppressive therapy in patients with childhood-onset ocular myasthenia gravis than in controls and decreased after immunosuppressive therapy. A significant positive correlation was observed between serum B cell-activating factor levels and anti-acetylcholine receptor antibody titers in patients with myasthenia gravis. Serum B cell-activating factor concentrations did not correlate with the percentages of CD4+, CD8+, and CD19+ cells or the CD4+/CD8+ ratio. No significant differences were observed in the levels of the 7 different types of cytokines examined, including interleukin-17A, between preimmunosuppressive therapy myasthenia gravis patients and controls. Circulating B cell-activating factor may play a key role in the pathophysiology of childhood-onset ocular myasthenia gravis. Copyright © 2015 Elsevier Inc. All rights reserved.

Plasma Cell Neoplasms (Including Multiple Myeloma) Treatment (PDQ®)—Health Professional Version

Cancer.gov

Plasma cell neoplasms (including multiple myeloma) treatment include observation, chemotherapy, radiation, stem cell rescue, targeted, and supportive therapies. Corticosteroids and immunomodulatory drugs may be used. Get detailed treatment information in this summary for clinicians.

B-cell activating factor detected on both naïve and memory B cells in bullous pemphigoid.

PubMed

Qian, Hua; Kusuhara, Masahiro; Li, Xiaoguang; Tsuruta, Daisuke; Tsuchisaka, Atsunari; Ishii, Norito; Koga, Hiroshi; Hayakawa, Taihei; Ohara, Koji; Karashima, Tadashi; Ohyama, Bungo; Ohata, Chika; Furumura, Minao; Hashimoto, Takashi

2014-08-01

B-cell activating factor (BAFF), an important immune regulatory cytokine, is involved in development of autoimmune diseases. Although BAFF is expressed in various cells, including dendritic cells (DCs) and monocytes, BAFF expression on B cells has not been well documented. In the present study, BAFF molecules on DCs and naïve and memory B cells in autoimmune bullous diseases, including pemphigus vulgaris, pemphigus foliaceus and bullous pemphigoid (BP), were analysed by flow cytometry. Compared with healthy controls (HC), BAFF expression on naïve and memory B cells increased significantly in BP. No difference in BAFF receptor expression in naïve and memory B cells was shown among all study groups. Furthermore, BAFF expression in both naïve and memory B cells of BP, but not HC, was detected by confocal microscopic analysis. These results implied that BAFF expressed by B cells may play a pathogenic role in autoimmune bullous diseases, particularly BP. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Cloning of a cancer cell-producing hepatocyte growth factor, vascular endothelial growth factor, and interleukin-8 from gastric cancer cells.

PubMed

Iwai, Mineko; Matsuda, Masahiko; Iwai, Yoshiaki

2003-01-01

A cell colony (IM95m) that produces hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF), and interleukin-8 (IL-8) was cloned from gastric cancer cells (IM95 cell line). In culture medium, the highest levels of HGF, VEGF, and IL-8 were about 1.1, 0.9, and 0.17 ng/ml culture medium at 3 d from 10(5) cells. IM95m may be useful in elucidating the role of tumor cells in angiogenesis.

Factors influencing the abundance of the side population in a human myeloma cell line.

PubMed

Mo, Sui-Lin; Li, Jia; Loh, Yen S; Brown, Ross D; Smith, Adrian L; Chen, Yuling; Joshua, Douglas; Roufogalis, Basil D; Li, George Q; Fan, Kei; Ng, Michelle C H; Sze, Daniel Man-Yuen

2011-01-01

Side population (SP) refers to a group of cells, which is capable to efflux Hoechst 33342, a DNA-binding dye. SP cells exist both in normal and tumor tissues. Although SP abundance has been used as an indicator for disease prognostic and drug screening in many research projects, few studies have systematically examined the factors influencing SP analysis. In this study we aim to develop a more thorough understanding of the multiple factors involved in SP analysis including Hoechst 33342 staining and cell culture. RPMI-8226, a high SP percentage (SP%) human myeloma cell line was employed here. The results showed that SP% was subject to staining conditions including: viable cell proportion, dye concentration, staining cell density, incubation duration, staining volume, and mix interval. In addition, SP% was highest in day one after passage, while dropped steadily over time. This study shows that both staining conditions and culture duration can significantly affect SP%. In this case, any conclusions based on SP% should be interpreted cautiously. The relation between culture duration and SP% suggests that the incidence of SP cells may be related to cell proliferation and cell cycle phase. Maintaining these technical variables consistently is essential in SP research.

Regulation of pancreatic islet beta-cell mass by growth factor and hormone signaling.

PubMed

Huang, Yao; Chang, Yongchang

2014-01-01

Dysfunction and destruction of pancreatic islet beta cells is a hallmark of diabetes. Better understanding of cellular signals in beta cells will allow development of therapeutic strategies for diabetes, such as preservation and expansion of beta-cell mass and improvement of beta-cell function. During the past several decades, the number of studies analyzing the molecular mechanisms, including growth factor/hormone signaling pathways that impact islet beta-cell mass and function, has increased exponentially. Notably, somatolactogenic hormones including growth hormone (GH), prolactin (PRL), and insulin-like growth factor-1 (IGF-1) and their receptors (GHR, PRLR, and IGF-1R) are critically involved in beta-cell growth, survival, differentiation, and insulin secretion. In this chapter, we focus more narrowly on GH, PRL, and IGF-1 signaling, and GH-IGF-1 cross talk. We also discuss how these signaling aspects contribute to the regulation of beta-cell proliferation and apoptosis. In particular, our novel findings of GH-induced formation of GHR-JAK2-IGF-1R protein complex and synergistic effects of GH and IGF-1 on beta-cell signaling, proliferation, and antiapoptosis lead to a new concept that IGF-1R may serve as a proximal component of GH/GHR signaling. © 2014 Elsevier Inc. All rights reserved.

Mast Cells Synthesize, Store, and Release Nerve Growth Factor

NASA Astrophysics Data System (ADS)

Leon, A.; Buriani, A.; dal Toso, R.; Fabris, M.; Romanello, S.; Aloe, L.; Levi-Montalcini, R.

1994-04-01

Mast cells and nerve growth factor (NGF) have both been reported to be involved in neuroimmune interactions and tissue inflammation. In many peripheral tissues, mast cells interact with the innervating fibers. Changes in the behaviors of both of these elements occur after tissue injury/inflammation. As such conditions are typically associated with rapid mast cell activation and NGF accumulation in inflammatory exudates, we hypothesized that mast cells may be capable of producing NGF. Here we report that (i) NGF mRNA is expressed in adult rat peritoneal mast cells; (ii) anti-NGF antibodies clearly stain vesicular compartments of purified mast cells and mast cells in histological sections of adult rodent mesenchymal tissues; and (iii) medium conditioned by peritoneal mast cells contains biologically active NGF. Mast cells thus represent a newly recognized source of NGF. The known actions of NGF on peripheral nerve fibers and immune cells suggest that mast cell-derived NGF may control adaptive/reactive responses of the nervous and immune systems toward noxious tissue perturbations. Conversely, alterations in normal mast cell behaviors may provoke maladaptive neuroimmune tissue responses whose consequences could have profound implications in inflammatory disease states, including those of an autoimmune nature.

Risk Factors for Breast Cancer, Including Occupational Exposures

PubMed Central

Meo, Margrethe; Vainio, Harri

2011-01-01

The knowledge on the etiology of breast cancer has advanced substantially in recent years, and several etiological factors are now firmly established. However, very few new discoveries have been made in relation to occupational risk factors. The International Agency for Research on Cancer has evaluated over 900 different exposures or agents to-date to determine whether they are carcinogenic to humans. These evaluations are published as a series of Monographs (www.iarc.fr). For breast cancer the following substances have been classified as "carcinogenic to humans" (Group 1): alcoholic beverages, exposure to diethylstilbestrol, estrogen-progestogen contraceptives, estrogen-progestogen hormone replacement therapy and exposure to X-radiation and gamma-radiation (in special populations such as atomic bomb survivors, medical patients, and in-utero exposure). Ethylene oxide is also classified as a Group 1 carcinogen, although the evidence for carcinogenicity in epidemiologic studies, and specifically for the human breast, is limited. The classification "probably carcinogenic to humans" (Group 2A) includes estrogen hormone replacement therapy, tobacco smoking, and shift work involving circadian disruption, including work as a flight attendant. If the association between shift work and breast cancer, the most common female cancer, is confirmed, shift work could become the leading cause of occupational cancer in women. PMID:22953181

Exposure to 60% oxygen promotes migration and upregulates angiogenesis factor secretion in breast cancer cells.

PubMed

Crowley, Peter D; Stuttgen, Vivian; O'Carroll, Emma; Ash, Simon A; Buggy, Donal J; Gallagher, Helen C

2017-01-01

Peri-operative factors, including anaesthetic drugs and techniques, may affect cancer cell biology and clinical recurrence. In breast cancer cells, we demonstrated that sevoflurane promotes migration and angiogenesis in high fractional oxygen but not in air. Follow-up analysis of the peri-operative oxygen fraction trial found an association between high inspired oxygen during cancer surgery and reduced tumor-free survival. Here we evaluated effects of acute, high oxygen exposure on breast cancer cell viability, migration and secretion of angiogenesis factors in vitro . MDA-MB-231 and MCF-7 breast cancer cells were exposed to 21%, 30%, 60%, or 80% v/v O 2 for 3 hours. Cell viability at 24 hours was determined by MTT and migration at 24 hours with the Oris™ Cell Migration Assay. Secretion of angiogenesis factors at 24 hours was measured via membrane-based immunoarray. Exposure to 30%, 60% or 80% oxygen did not affect cell viability. Migration of MDA-MB-231 and MCF-7 cells was increased by 60% oxygen ( P = 0.012 and P = 0.007, respectively) while 30% oxygen increased migration in MCF-7 cells ( P = 0.011). These effects were reversed by dimethyloxaloylglycine. In MDA-MB-231 cells high fractional oxygen increased secretion of angiogenesis factors monocyte chemotactic protein 1, regulated on activation normal T-cell expressed and vascular endothelial growth factor. In MCF-7 cells, interleukin-8, angiogenin and vascular endothelial growth factor secretion was significantly increased by high fractional oxygen. High oxygen exposure stimulates migration and secretion of angiogenesis factors in breast cancer cells in vitro .

Fuel cell repeater unit including frame and separator plate

DOEpatents

Yamanis, Jean; Hawkes, Justin R; Chiapetta, Jr., Louis; Bird, Connie E; Sun, Ellen Y; Croteau, Paul F

2013-11-05

An example fuel cell repeater includes a separator plate and a frame establishing at least a portion of a flow path that is operative to communicate fuel to or from at least one fuel cell held by the frame relative to the separator plate. The flow path has a perimeter and any fuel within the perimeter flow across the at least one fuel cell in a first direction. The separator plate, the frame, or both establish at least one conduit positioned outside the flow path perimeter. The conduit is outside of the flow path perimeter and is configured to direct flow in a second, different direction. The conduit is fluidly coupled with the flow path.

General Information about Plasma Cell Neoplasms (Including Multiple Myeloma)

MedlinePlus

... Including Multiple Myeloma) Treatment (PDQ®)–Patient Version General Information About Plasma Cell Neoplasms Go to Health Professional ... the PDQ Adult Treatment Editorial Board . Clinical Trial Information A clinical trial is a study to answer ...

Membrane-To-Nucleus Signaling Links Insulin-Like Growth Factor-1- and Stem Cell Factor-Activated Pathways

PubMed Central

Hayashi, Yujiro; Asuzu, David T.; Gibbons, Simon J.; Aarsvold, Kirsten H.; Bardsley, Michael R.; Lomberk, Gwen A.; Mathison, Angela J.; Kendrick, Michael L.; Shen, K. Robert; Taguchi, Takahiro; Gupta, Anu; Rubin, Brian P.; Fletcher, Jonathan A.; Farrugia, Gianrico; Urrutia, Raul A.; Ordog, Tamas

2013-01-01

Stem cell factor (mouse: Kitl, human: KITLG) and insulin-like growth factor-1 (IGF1), acting via KIT and IGF1 receptor (IGF1R), respectively, are critical for the development and integrity of several tissues. Autocrine/paracrine KITLG-KIT and IGF1-IGF1R signaling are also activated in several cancers including gastrointestinal stromal tumors (GIST), the most common sarcoma. In murine gastric muscles, IGF1 promotes Kitl-dependent development of interstitial cells of Cajal (ICC), the non-neoplastic counterpart of GIST, suggesting cooperation between these pathways. Here, we report a novel mechanism linking IGF1-IGF1R and KITLG-KIT signaling in both normal and neoplastic cells. In murine gastric muscles, the microenvironment for ICC and GIST, human hepatic stellate cells (LX-2), a model for cancer niches, and GIST cells, IGF1 stimulated Kitl/KITLG protein and mRNA expression and promoter activity by activating several signaling pathways including AKT-mediated glycogen synthase kinase-3β inhibition (GSK3i). GSK3i alone also stimulated Kitl/KITLG expression without activating mitogenic pathways. Both IGF1 and GSK3i induced chromatin-level changes favoring transcriptional activation at the Kitl promoter including increased histone H3/H4 acetylation and H3 lysine (K) 4 methylation, reduced H3K9 and H3K27 methylation and reduced occupancy by the H3K27 methyltransferase EZH2. By pharmacological or RNA interference-mediated inhibition of chromatin modifiers we demonstrated that these changes have the predicted impact on KITLG expression. KITLG knock-down and immunoneutralization inhibited the proliferation of GIST cells expressing wild-type KIT, signifying oncogenic autocrine/paracrine KITLG-KIT signaling. We conclude that membrane-to-nucleus signaling involving GSK3i establishes a previously unrecognized link between the IGF1-IGF1R and KITLG-KIT pathways, which is active in both physiologic and oncogenic contexts and can be exploited for therapeutic purposes. PMID:24116170

Pluripotent Conversion of Muscle Stem Cells Without Reprogramming Factors or Small Molecules.

PubMed

Bose, Bipasha; Shenoy P, Sudheer

2016-02-01

Muscle derived stem cells (MDSCs) are multipotent stem cells that can differentiate into several lineages including skeletal muscle precursor cells. Here, we show that MDSCs from myostatin null mice (Mstn (-/-) ) can be readily induced into pluripotent stem cells without using reprogramming factors. Microarray studies revealed a strong upregulation of markers like Leukemia Inhibitory factor (LIF) and Leukemia Inhibitory factor receptor (LIFR) in Mstn (-/-) MDSCs as compared to wild type MDSCs (WT-MDSCs). Furthermore when cultured in mouse embryonic stem cell media with LIF for 95 days, Mstn (-/-) MDSCs formed embryonic stem cell (ES) like colonies. We termed such ES like cells as the culture-induced pluripotent stem cells (CiPSC). CiPSCs from Mstn (-/-) MDSCs were phenotypically similar to ESCs, expressed high levels of Oct4, Nanog, Sox2 and SSEA-1, maintained a normal karyotype. Furthermore, CiPSCs formed embryoid bodies and teratomas when injected into immunocompromised mice. In addition, CiPSCs differentiated into somatic cells of all three lineages. We further show that culturing in ES cell media, resulted in hypermethylation and downregulation of BMP2 in Mstn(-/-) MDSCs. Western blot further confirmed a down regulation of BMP2 signaling in Mstn (-/-) MDSCs in supportive of pluripotent reprogramming. Given that down regulation of BMP2 has been shown to induce pluripotency in cells, we propose that lack of myostatin epigenetically reprograms the MDSCs to become pluripotent stem cells. Thus, here we report the successful establishment of ES-like cells from adult stem cells of the non-germline origin under culture-induced conditions without introducing reprogramming genes.

Treatment with specific soluble factors promotes the functional maturation of transcription factor-mediated, pancreatic transdifferentiated cells.

PubMed

Motoyama, Hiroaki; Kobayashi, Akira; Yokoyama, Takahide; Shimizu, Akira; Sakai, Hiroshi; Notake, Tsuyoshi; Fukushima, Kentaro; Miyagawa, Shin-Ichi

2018-01-01

Pancreatic lineage-specific transcription factors (TFs) display instructive roles in converting adult cells to endocrine pancreatic cells through a process known as transdifferentiation. However, little is known about potential factors capable of accelerating transdifferentiation following transduction to achieve the functional maturation of transdifferentiated cells. In this study, we demonstrated, using adult liver-derived progenitor cells, that soluble factors utilized in pancreatic differentiation protocols of pluripotent stem cells promote functional maturation of TFs-mediated transdifferentiated cells. Treatment with an N2 supplement in combination with three soluble factors (glucagon-like peptide-1 [GLP-1] receptor agonist, notch inhibitor, and transforming growth factor-β [TGF-β] inhibitor) enhanced liver-to-pancreas transdifferentiation based on the following findings: i) the incidence of c-peptide-positive cells increased by approximately 1.2-fold after the aforementioned treatment; ii) the c-peptide expression level in the treated cells increased by approximately 12-fold as compared with the level in the untreated cells; iii) the treated cells secreted insulin in a glucose-dependent manner, whereas the untreated cells did not; and iv) transplantation of treated-transdifferentiated cells into streptozotocin-induced immunodeficient diabetic mice led to the amelioration of hyperglycemia. These results suggest that treatment with specific soluble factors promotes the functional maturation of transdifferentiated cells. Our findings could facilitate the development of new modalities for cell-replacement therapy for patients with diabetes.

Identification of Key Transcription Factors Associated with Lung Squamous Cell Carcinoma

PubMed Central

Zhang, Feng; Chen, Xia; Wei, Ke; Liu, Daoming; Xu, Xiaodong; Zhang, Xing; Shi, Hong

2017-01-01

Background Lung squamous cell carcinoma (lung SCC) is a common type of lung cancer, but its mechanism of pathogenesis is unclear. The aim of this study was to identify key transcription factors in lung SCC and elucidate its mechanism. Material/Methods Six published microarray datasets of lung SCC were downloaded from Gene Expression Omnibus (GEO) for integrated bioinformatics analysis. Significance analysis of microarrays was used to identify differentially expressed genes (DEGs) between lung SCC and normal controls. The biological functions and signaling pathways of DEGs were mapped in the Gene Otology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database, respectively. A transcription factor gene regulatory network was used to obtain insights into the functions of DEGs. Results A total of 1,011 genes, including 539 upregulated genes and 462 downregulated genes, were filtered as DEGs between lung SCC and normal controls. DEGs were significantly enriched in cell cycle, DNA replication, p53 signaling pathway, pathways in cancer, adherens junction, and cell adhesion molecules signaling pathways. There were 57 transcription factors identified, which were used to construct a regulatory network. The network consisted of 736 interactions between 49 transcription factors and 486 DEGs. NFIC, BRCA1, and NFATC2 were the top 3 transcription factors that had the highest connectivity with DEGs and that regulated 83, 82, and 75 DEGs in the network, respectively. Conclusions NFIC, BRCA1, and NFATC2 might be the key transcription factors in the development of lung SCC by regulating the genes involved in cell cycle and DNA replication pathways. PMID:28081052

A micromanipulation cell including a tool changer

NASA Astrophysics Data System (ADS)

Clévy, Cédric; Hubert, Arnaud; Agnus, Joël; Chaillet, Nicolas

2005-10-01

This paper deals with the design, fabrication and characterization of a tool changer for micromanipulation cells. This tool changer is part of a manipulation cell including a three linear axes robot and a piezoelectric microgripper. All these parts are designed to perform micromanipulation tasks in confined spaces such as a microfactory or in the chamber of a scanning electron microscope (SEM). The tool changer principle is to fix a pair of tools (i.e. the gripper tips) either on the tips of the microgripper actuator (piezoceramic bulk) or on a tool magazine. The temperature control of a thermal glue enables one to fix or release this pair of tools. Liquefaction and solidification are generated by surface mounted device (SMD) resistances fixed on the surface of the actuator or magazine. Based on this principle, the tool changer can be adapted to other kinds of micromanipulation cells. Hundreds of automatic tool exchanges were performed with a maximum positioning error between two consecutive tool exchanges of 3.2 µm, 2.3 µm and 2.8 µm on the X, Y and Z axes respectively (Z refers to the vertical axis). Finally, temperature measurements achieved under atmospheric pressure and in a vacuum environment and pressure measurements confirm the possibility of using this device in the air as well as in a SEM.

Red blood cells release factors with growth and survival bioactivities for normal and leukemic T cells.

PubMed

Antunes, Ricardo F; Brandão, Cláudia; Maia, Margarida; Arosa, Fernando A

2011-01-01

Human red blood cells are emerging as a cell type capable to regulate biological processes of neighboring cells. Hereby, we show that human red blood cell conditioned media contains bioactive factors that favor proliferation of normal activated T cells and leukemic Jurkat T cells, and therefore called erythrocyte-derived growth and survival factors. Flow cytometry and electron microscopy in parallel with bioactivity assays revealed that the erythrocyte factors are present in the vesicle-free supernatant, which contains up to 20 different proteins. The erythrocyte factors are thermosensitive and do not contain lipids. Native polyacrylamide gel electrophoresis followed by passive elution and mass spectrometry identification reduced the potential erythrocyte factors to hemoglobin and peroxiredoxin II. Two-dimensional differential gel electrophoresis of the erythrocyte factors revealed the presence of multiple hemoglobin oxy-deoxy states and peroxiredoxin II isoforms differing in their isoelectric point akin to the presence of β-globin chains. Our results show that red blood cells release protein factors with the capacity to sustain T-cell growth and survival. These factors may have an unforeseen role in sustaining malignant cell growth and survival in vivo.

Cell-line-specific stimulation of tumor cell aggressiveness by wound healing factors - a central role for STAT3.

PubMed

Ekblad, Lars; Lindgren, Gustaf; Persson, Emma; Kjellén, Elisabeth; Wennerberg, Johan

2013-01-25

Local recurrence is a major factor affecting survival after treatment for head and neck squamous cell carcinoma (HNSCC). It is possible that the normal processes involved in wound healing after surgical removal of a primary tumor can boost the regrowth of residual cancer cells, thereby contributing to the recurrent growth. In this work, we collected human wound fluids and used them to investigate the effect of wound healing factors on HNSCC cell lines in vitro. Wound fluids were collected from thyroidectomized patients diagnosed with benign disease and were included in assays of cell proliferation, migration, cell scattering, and invasion. The involvement of intracellular signaling pathways and membrane receptors were investigated by western blotting and the inclusion of specific inhibitors. One out of four cell lines was greatly stimulated in proliferation, migration, cell scattering, and invasion by the addition of wound fluid as compared with addition of fetal bovine or human serum. These effects were accompanied by a sharp increase in activation of signal transducer and activator of transcription 3 (STAT3). Inhibition of STAT3 activation abolished the wound fluid response, showing that STAT3 plays an important role in the wound healing response. Several of the observed phenotypic changes were epithelial-to-mesenchymal transition (EMT)-like, but the appropriate changes were not seen in any of the EMT markers investigated. The involvement of c-Met or epidermal growth factor receptor family members was excluded, while the interleukin-6 receptor was found to be partly responsible for the activation of STAT3. In conclusion, we found cell-line-specific effects of wound healing factors on HNSCC, setting the stage for therapy development and predictive opportunities.

Expression dynamics of self-renewal factors for spermatogonial stem cells in the mouse testis.

PubMed

Sakai, Mizuki; Masaki, Kaito; Aiba, Shota; Tone, Masaaki; Takashima, Seiji

2018-04-16

Glial cell line-derived neurotrophic factor (GDNF) and fibroblast growth factor 2 (FGF2) are bona fide self-renewal factors for spermatogonial stem cells (SSCs). Although GDNF is indispensable for the maintenance of SSCs, the role of FGF2 in the testis remains to be elucidated. To clarify this, the expression dynamics and regulatory mechanisms of Fgf2 and Gdnf in the mouse testes were analyzed. It is well known that Sertoli cells express Gdnf, and its receptor is expressed in a subset of undifferentiated spermatogonia, including SSCs. However, we found that Fgf2 was mainly expressed in the germ cells and its receptors were expressed not only in the cultured spermatogonial cell line, but also in testicular somatic cells. Aging, hypophysectomy, retinoic acid treatment, and testicular injury induced distinct Fgf2 and Gdnf expression dynamics, suggesting a difference in the expression mechanism of Fgf2 and Gdnf in the testis. Such differences might cause a dynamic fluctuation of Gdnf/Fgf2 ratio depending on the intrinsic/extrinsic cues. Considering that FGF2-cultured spermatogonia exhibit more differentiated phenotype than those cultured with GDNF, FGF2 might play a role distinct from that of GDNF in the testis, despite the fact that both factors are self-renewal factor for SSC in vitro.

Genetics and risk factors for basal cell carcinoma.

PubMed

Madan, V; Hoban, P; Strange, R C; Fryer, A A; Lear, J T

2006-05-01

Nonmelanoma skin cancer (NMSC) is the commonest cancer in whites and its incidence is increasing worldwide. The prevalence of this cancer is predicted to equal that of all others combined and it was estimated that there were over 2 million cases diagnosed in the U.S.A. in 2004. Patients exhibit marked differences in clinical phenotype with variations in tumour numbers, rate of tumour accrual, site and histological subtype. Furthermore, patients are at increased risk of other cutaneous and noncutaneous cancers. The factors accounting for this variation are complex and still not completely understood. Clearly, ultraviolet light (UV) exposure is a major influence but its relationship to clinical phenotype is not yet clear. In addition, immunosuppression is a significant risk factor. Our group has identified high-risk groups for the development of further basal cell carcinoma (BCC), namely patients with truncal BCC and those presenting with tumour clusters. This presentation will concentrate on these clinical subgroups as well as immunosuppressed patients. These groups represent significant management challenges and are areas where novel, nonsurgical treatment options may make a significant clinical impact in patient care. The risk factors predisposing to these clinical phenotypes will be discussed, including genetic factors and UV exposure. Potential clinical applications, including predictive indices, will be considered.

Signaling by Kit protein-tyrosine kinase--the stem cell factor receptor.

PubMed

Roskoski, Robert

2005-11-11

Signaling by stem cell factor and Kit, its receptor, plays important roles in gametogenesis, hematopoiesis, mast cell development and function, and melanogenesis. Moreover, human and mouse embryonic stem cells express Kit transcripts. Stem cell factor exists as both a soluble and a membrane-bound glycoprotein while Kit is a receptor protein-tyrosine kinase. The complete absence of stem cell factor or Kit is lethal. Deficiencies of either produce defects in red and white blood cell production, hypopigmentation, and sterility. Gain-of-function mutations of Kit are associated with several human neoplasms including acute myelogenous leukemia, gastrointestinal stromal tumors, and mastocytomas. Kit consists of an extracellular domain, a transmembrane segment, a juxtamembrane segment, and a protein kinase domain that contains an insert of about 80 amino acid residues. Binding of stem cell factor to Kit results in receptor dimerization and activation of protein kinase activity. The activated receptor becomes autophosphorylated at tyrosine residues that serve as docking sites for signal transduction molecules containing SH2 domains. The adaptor protein APS, Src family kinases, and Shp2 tyrosyl phosphatase bind to phosphotyrosine 568. Shp1 tyrosyl phosphatase and the adaptor protein Shc bind to phosphotyrosine 570. C-terminal Src kinase homologous kinase and the adaptor Shc bind to both phosphotyrosines 568 and 570. These residues occur in the juxtamembrane segment of Kit. Three residues in the kinase insert domain are phosphorylated and attract the adaptor protein Grb2 (Tyr703), phosphatidylinositol 3-kinase (Tyr721), and phospholipase Cgamma (Tyr730). Phosphotyrosine 900 in the distal kinase domain binds phosphatidylinositol 3-kinase which in turn binds the adaptor protein Crk. Phosphotyrosine 936, also in the distal kinase domain, binds the adaptor proteins APS, Grb2, and Grb7. Kit has the potential to participate in multiple signal transduction pathways as a result of

Natural Killer Cells Promote Fetal Development through the Secretion of Growth-Promoting Factors.

PubMed

Fu, Binqing; Zhou, Yonggang; Ni, Xiang; Tong, Xianhong; Xu, Xiuxiu; Dong, Zhongjun; Sun, Rui; Tian, Zhigang; Wei, Haiming

2017-12-19

Natural killer (NK) cells are present in large populations at the maternal-fetal interface during early pregnancy. However, the role of NK cells in fetal growth is unclear. Here, we have identified a CD49a + Eomes + subset of NK cells that secreted growth-promoting factors (GPFs), including pleiotrophin and osteoglycin, in both humans and mice. The crosstalk between HLA-G and ILT2 served as a stimulus for GPF-secreting function of this NK cell subset. Decreases in this GPF-secreting NK cell subset impaired fetal development, resulting in fetal growth restriction. The transcription factor Nfil3, but not T-bet, affected the function and the number of this decidual NK cell subset. Adoptive transfer of induced CD49a + Eomes + NK cells reversed impaired fetal growth and rebuilt an appropriate local microenvironment. These findings reveal properties of NK cells in promoting fetal growth. In addition, this research proposes approaches for therapeutic administration of NK cells in order to reverse restricted nourishments within the uterine microenvironment during early pregnancy. Copyright © 2017 Elsevier Inc. All rights reserved.

Hypoxia-inducible Factor Regulates αvβ3 Integrin Cell Surface Expression

PubMed Central

Cowden Dahl, Karen D.; Robertson, Sarah E.; Weaver, Valerie M.; Simon, M. Celeste

2005-01-01

Hypoxia-inducible factor (HIF)-deficient placentas exhibit a number of defects, including changes in cell fate adoption, lack of fetal angiogenesis, hypocellularity, and poor invasion into maternal tissue. HIF is a heterodimeric transcription factor consisting of α and β aryl hydrocarbon receptor nuclear translocator or ARNT) subunits. We used undifferentiated trophoblast stem (TS) cells to characterize HIF-dependent adhesion, migration, and invasion. Arnt-/- and Hifα-/- TS cells exhibit reduced adhesion and migration toward vitronectin compared with wild-type cells. Furthermore, this defect is associated with decreased cell surface expression of integrin αvβ3 and significantly decreased expression of this integrin in focal adhesions. Because of the importance of adhesion and migration in tumor progression (in addition to placental development), we examined the affect of culturing B16F0 melanoma cells in 1.5% oxygen (O2). Culturing B16F0 melanoma cells at 1.5% O2 resulted in increased αvβ3 integrin surface expression and increased adhesion to and migration toward vitronectin. Together, these data suggest that HIF and O2 tension influence placental invasion and tumor migration by increasing cell surface expression of αvβ3 integrin. PMID:15689487

Effects of heparin-binding epidermal growth factor-like growth factor on cell repopulation and signal transduction in periodontal ligament cells after scratch wounding in vitro.

PubMed

Lee, J S; Kim, J M; Hong, E K; Kim, S-O; Yoo, Y-J; Cha, J-H

2009-02-01

A growing amount of attention has been placed on periodontal regeneration and wound healing for periodontal therapy. This study was conducted in an effort to determine the effects of heparin-binding epidermal growth factor-like growth factor on cell repopulation and signal transduction in periodontal ligament cells after scratch wounding in vitro. Human periodontal ligament cells were acquired from explant tissue of human healthy periodontal ligament. After the wounding of periodontal ligament cells, the change in expression of heparin-binding epidermal growth factor-like growth factor and epidermal growth factor receptors 1-4 mRNA was assessed. The effects of heparin-binding epidermal growth factor-like growth factor on periodontal ligament cell proliferation and repopulation were assessed in vitro via the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and by photographing the injuries, respectively. Extracellular signal-regulated kinase (Erk)1/2, p38 and Akt phosphorylation was characterized via western blotting. Scratch wounding resulted in a significant up-regulation of heparin-binding epidermal growth factor-like growth factor mRNA expression, whereas wounding had no effect on the expression levels of epidermal growth factor receptors 1-4. Interestingly, no expression of epidermal growth factor receptors 2 and 4 was detectable prior to or after wounding. Heparin-binding epidermal growth factor-like growth factor treatment promoted the proliferation and repopulation of periodontal ligament cells. The scratch wounding also stimulated the phosphorylation of Erk1/2 and p38, but not of Akt, in periodontal ligament cells, and heparin-binding epidermal growth factor-like growth factor treatment applied after wounding amplified and extended the activations of Erk1/2 and p38, but not of Akt. Furthermore, Erk1/2 inhibition blocked the process of cell repopulation induced by heparin-binding epidermal growth factor-like growth factor, whereas the

The Janus-faced roles of Krüppel-like factor 4 in oral squamous cell carcinoma cells.

PubMed

Li, Wenwen; Liu, Man; Su, Ying; Zhou, Xinying; Liu, Yao; Zhang, Xinyan

2015-12-29

Krüppel-like factor 4 (KLF4) is a zinc-finger transcription factor that regulates many essential processes, including development and cell differentiation, proliferation, and apoptosis. Along with these roles in normal cells and tissues, KLF4 has important tumor suppressive and oncogenic functions in some malignancies. However, the roles of KLF4 in oral squamous cell carcinoma remain unclear. This study investigated the epigenetic alterations and possible roles of KLF4 in oral cancer carcinogenesis. Notably, KLF4 expression was significantly decreased in human oral cancer tissues compared with healthy controls, and KLF4 promoter hypermethylation contributed to the suppression of KLF4 expression. KLF4 expression was associated with tumor grade. Its expression was much lower in poorly differentiated oral cancers than in well-differentiated cancer cells. KLF4 exerted its antitumor activity in vitro and/or in vivo by inhibiting cell proliferation, cell cycle progression, cell colony formation and by inducing apoptosis. In addition, KLF4 over-expression promoted oral cancer cell migration and invasion in vitro. Knockdown of KLF4 promoted oral cancer cells growth and colony formation, and simultaneously inhibited cell migration and invasion. Mechanistic studies revealed that MMP-9 might contribute to KLF4-mediated cell migration and invasion. These results provide evidence that KLF4 might play Janus-faced roles in oral cancer carcinogenesis, acting both as a tumor suppressor and as an oncogene.

Bovine trophectoderm cell lines induced from bovine fibroblasts with reprogramming factors

USDA-ARS?s Scientific Manuscript database

Bovine trophectoderm (TE) cells were induced [induced bovine trophectoderm-like (iBT)] from bovine fetal liver-derived fibroblasts, and other bovine fetal fibroblasts, after viral-vector transduction with either four or six reprogramming factors (RF), including POU5F1, KLF4, SOX2, C-MYC, SV40 large ...

Hypoxia enhances the interaction between pancreatic stellate cells and cancer cells via increased secretion of connective tissue growth factor.

PubMed

Eguchi, Daiki; Ikenaga, Naoki; Ohuchida, Kenoki; Kozono, Shingo; Cui, Lin; Fujiwara, Kenji; Fujino, Minoru; Ohtsuka, Takao; Mizumoto, Kazuhiro; Tanaka, Masao

2013-05-01

Pancreatic cancer (PC), a hypovascular tumor, thrives under hypoxic conditions. Pancreatic stellate cells (PSCs) promote PC progression by secreting soluble factors, but their functions in hypoxia are poorly understood. This study aimed to clarify the effects of hypoxic conditions on the interaction between PC cells and PSCs. We isolated human PSCs from fresh pancreatic ductal adenocarcinomas and analyzed functional differences in PSCs between normoxia (21% O2) and hypoxia (1% O2), including expression of various factors related to tumor-stromal interactions. We particularly analyzed effects on PC invasiveness of an overexpressed molecule-connective tissue growth factor (CTGF)-in PSCs under hypoxic conditions, using RNA interference techniques. Conditioned media from hypoxic PSCs enhanced PC cell invasiveness more intensely than that from normoxic PSCs (P < 0.01). When co-cultured with PSCs, PC cell invasion was more enhanced under hypoxia than under normoxia (P < 0.05). Among various soluble factors, which were related to invasiveness, CTGF was one of the overexpressed molecules in hypoxic PSCs. A higher level of CTGF expression was also found in supernatant of hypoxic PSCs than in supernatant of normoxic PSCs. PC cell invasiveness was reduced by CTGF knockdown in hypoxic PSCs co-cultured with PC cells (P < 0.05). Hypoxia induces PSCs' secretion of CTGF, leading to enhancement of PC invasiveness. CTGF derived from hypoxia-stimulated PSCs may be a new therapeutic target for pancreatic cancer. Copyright © 2013 Elsevier Inc. All rights reserved.

Tissue factor expression by endothelial cells in sickle cell anemia.

PubMed

Solovey, A; Gui, L; Key, N S; Hebbel, R P

1998-05-01

The role of the vascular endothelium in activation of the coagulation system, a fundamental homeostatic mechanism of mammalian biology, is uncertain because there is little evidence indicating that endothelial cells in vivo express tissue factor (TF), the system's triggering mechanism. As a surrogate for vessel wall endothelium, we examined circulating endothelial cells (CEC) from normals and patients with sickle cell anemia, a disease associated with activation of coagulation. We find that sickle CEC abnormally express TF antigen (expressed as percent CEC that are TF-positive), with 66+/-13% positive in sickle patients in steady-state, 83+/-19% positive in sickle patients presenting with acute vasoocclusive episodes, and only 10+/-13% positive in normal controls. Repeated samplings confirmed this impression that TF expression is greater when sickle patients develop acute vasoocclusive episodes. Sickle CEC are also positive for TF mRNA, with excellent concurrence between antigen and mRNA expression. The TF expressed on the antigen-positive CEC is functional, as demonstrated by a binding assay for Factor VIIa and a chromogenic assay sensitive to generation of Factor Xa. By establishing that endothelial cells in vivo can express TF, these data imply that the vast endothelial surface area does provide an important pathophysiologic trigger for coagulation activation.

BAFF, a Novel Ligand of the Tumor Necrosis Factor Family, Stimulates B Cell Growth

PubMed Central

Schneider, Pascal; MacKay, Fabienne; Steiner, Véronique; Hofmann, Kay; Bodmer, Jean-Luc; Holler, Nils; Ambrose, Christine; Lawton, Pornsri; Bixler, Sarah; Acha-Orbea, Hans; Valmori, Danila; Romero, Pedro; Werner-Favre, Christiane; Zubler, Rudolph H.; Browning, Jeffrey L.; Tschopp, Jürg

1999-01-01

Members of the tumor necrosis factor (TNF) family induce pleiotropic biological responses, including cell growth, differentiation, and even death. Here we describe a novel member of the TNF family, designated BAFF (for B cell activating factor belonging to the TNF family), which is expressed by T cells and dendritic cells. Human BAFF was mapped to chromosome 13q32-34. Membrane-bound BAFF was processed and secreted through the action of a protease whose specificity matches that of the furin family of proprotein convertases. The expression of BAFF receptor appeared to be restricted to B cells. Both membrane-bound and soluble BAFF induced proliferation of anti-immunoglobulin M–stimulated peripheral blood B lymphocytes. Moreover, increased amounts of immunoglobulins were found in supernatants of germinal center–like B cells costimulated with BAFF. These results suggest that BAFF plays an important role as costimulator of B cell proliferation and function. PMID:10359578

Mannitol-Enhanced Delivery of Stem Cells and Their Growth Factors Across the Blood–Brain Barrier

PubMed Central

Gonzales-Portillo, Gabriel S.; Sanberg, Paul R.; Franzblau, Max; Gonzales-Portillo, Chiara; Diamandis, Theo; Staples, Meaghan; Sanberg, Cyndy D.; Borlongan, Cesar V.

2014-01-01

Ischemic brain injury in adults and neonates is a significant clinical problem with limited therapeutic interventions. Currently, clinicians have only tPA available for stroke treatment and hypothermia for cerebral palsy. Owing to the lack of treatment options, there is a need for novel treatments such as stem cell therapy. Various stem cells including cells from embryo, fetus, perinatal, and adult tissues have proved effective in preclinical and small clinical trials. However, a limiting factor in the success of these treatments is the delivery of the cells and their by-products (neurotrophic factors) into the injured brain. We have demonstrated that mannitol, a drug with the potential to transiently open the blood–brain barrier and facilitate the entry of stem cells and trophic factors, as a solution to the delivery problem. The combination of stem cell therapy and mannitol may improve therapeutic outcomes in adult stroke and neonatal cerebral palsy. PMID:24480552

Tumor necrosis factor-{alpha} enhanced fusions between oral squamous cell carcinoma cells and endothelial cells via VCAM-1/VLA-4 pathway

DOE Office of Scientific and Technical Information (OSTI.GOV)

Song, Kai; Zhu, Fei; Zhang, Han-zhong

Fusion between cancer cells and host cells, including endothelial cells, may strongly modulate the biological behavior of tumors. However, no one is sure about the driving factors and underlying mechanism involved in such fusion. We hypothesized in this study that inflammation, one of the main characteristics in tumor microenvironment, serves as a prominent catalyst for fusion events. Our results showed that oral cancer cells can fuse spontaneously with endothelial cells in co-culture and inflammatory cytokine tumor necrosis factor-{alpha} (TNF-{alpha}) increased fusion of human umbilical vein endothelium cells and oral cancer cells by up to 3-fold in vitro. Additionally, human oralmore » squamous cell carcinoma cell lines and 35 out of 50 (70%) oral squamous carcinoma specimens express VLA-4, an integrin, previously implicated in fusions between human peripheral blood CD34-positive cells and murine cardiomyocytes. Expression of VCAM-1, a ligand for VLA-4, was evident on vascular endothelium of oral squamous cell carcinoma. Moreover, immunocytochemistry and flow cytometry analysis revealed that expression of VCAM-1 increased obviously in TNF-{alpha}-stimulated endothelial cells. Anti-VLA-4 or anti-VCAM-1 treatment can decrease significantly cancer-endothelial adhesion and block such fusion. Collectively, our results suggested that TNF-{alpha} could enhance cancer-endothelial cell adhesion and fusion through VCAM-1/VLA-4 pathway. This study provides insights into regulatory mechanism of cancer-endothelial cell fusion, and has important implications for the development of novel therapeutic strategies for prevention of metastasis. -- Highlights: Black-Right-Pointing-Pointer Spontaneous oral cancer-endothelial cell fusion. Black-Right-Pointing-Pointer TNF-{alpha} enhanced cell fusions. Black-Right-Pointing-Pointer VCAM-1/VLA-4 expressed in oral cancer. Black-Right-Pointing-Pointer TNF-{alpha} increased expression of VCAM-1 on endothelial cells. Black

Multiple transcription factors directly regulate Hox gene lin-39 expression in ventral hypodermal cells of the C. elegans embryo and larva, including the hypodermal fate regulators LIN-26 and ELT-6.

PubMed

Liu, Wan-Ju; Reece-Hoyes, John S; Walhout, Albertha J M; Eisenmann, David M

2014-05-13

Hox genes encode master regulators of regional fate specification during early metazoan development. Much is known about the initiation and regulation of Hox gene expression in Drosophila and vertebrates, but less is known in the non-arthropod invertebrate model system, C. elegans. The C. elegans Hox gene lin-39 is required for correct fate specification in the midbody region, including the Vulval Precursor Cells (VPCs). To better understand lin-39 regulation and function, we aimed to identify transcription factors necessary for lin-39 expression in the VPCs, and in particular sought factors that initiate lin-39 expression in the embryo. We used the yeast one-hybrid (Y1H) method to screen for factors that bound to 13 fragments from the lin-39 region: twelve fragments contained sequences conserved between C. elegans and two other nematode species, while one fragment was known to drive reporter gene expression in the early embryo in cells that generate the VPCs. Sixteen transcription factors that bind to eight lin-39 genomic fragments were identified in yeast, and we characterized several factors by verifying their physical interactions in vitro, and showing that reduction of their function leads to alterations in lin-39 levels and lin-39::GFP reporter expression in vivo. Three factors, the orphan nuclear hormone receptor NHR-43, the hypodermal fate regulator LIN-26, and the GATA factor ELT-6 positively regulate lin-39 expression in the embryonic precursors to the VPCs. In particular, ELT-6 interacts with an enhancer that drives GFP expression in the early embryo, and the ELT-6 site we identified is necessary for proper embryonic expression. These three factors, along with the factors ZTF-17, BED-3 and TBX-9, also positively regulate lin-39 expression in the larval VPCs. These results significantly expand the number of factors known to directly bind and regulate lin-39 expression, identify the first factors required for lin-39 expression in the embryo, and hint at a

Ginger inhibits cell growth and modulates angiogenic factors in ovarian cancer cells

PubMed Central

Rhode, Jennifer; Fogoros, Sarah; Zick, Suzanna; Wahl, Heather; Griffith, Kent A; Huang, Jennifer; Liu, J Rebecca

2007-01-01

Background Ginger (Zingiber officinale Rosc) is a natural dietary component with antioxidant and anticarcinogenic properties. The ginger component [6]-gingerol has been shown to exert anti-inflammatory effects through mediation of NF-κB. NF-κB can be constitutively activated in epithelial ovarian cancer cells and may contribute towards increased transcription and translation of angiogenic factors. In the present study, we investigated the effect of ginger on tumor cell growth and modulation of angiogenic factors in ovarian cancer cells in vitro. Methods The effect of ginger and the major ginger components on cell growth was determined in a panel of epithelial ovarian cancer cell lines. Activation of NF-κB and and production of VEGF and IL-8 was determined in the presence or absence of ginger. Results Ginger treatment of cultured ovarian cancer cells induced profound growth inhibition in all cell lines tested. We found that in vitro, 6-shogaol is the most active of the individual ginger components tested. Ginger treatment resulted in inhibition of NF-kB activation as well as diminished secretion of VEGF and IL-8. Conclusion Ginger inhibits growth and modulates secretion of angiogenic factors in ovarian cancer cells. The use of dietary agents such as ginger may have potential in the treatment and prevention of ovarian cancer. PMID:18096028

Hydrogen Peroxide-Reducing Factor Released by PC12D Cells Increases Cell Tolerance against Oxidative Stress.

PubMed

Muraishi, Asami; Haneta, Emi; Saito, Yoshiro; Hitomi, Yutaka; Sano, Mamoru; Noguchi, Noriko

2018-01-01

PC12D cells, a subline of rat adrenal pheochromocytoma PC12 cells, extend neurites rapidly in response to differentiation stimuli and are used to investigate the molecular mechanisms of neurite extension. In the present study, we found significant tolerance of PC12D cells against Parkinson's disease-related stimuli such as dopamine and 6-hydroxydopamine; this tolerance was significantly decreased by a change in the medium. Conditioned medium from PC12D cells induced tolerance against oxidative stress, which suggests that cytoprotective factor may be released by PC12D cells into the culture medium. Conditioned medium-induced tolerance was not found for PC12 cells or human neuroblastoma SH-SY5Y cells. A cytoprotective factor generated by PC12D cells exhibited hydrogen peroxide-reducing activity. Chemical characterization showed that this cytoprotective factor is water soluble and has a molecular weight about 1000 Da, and that its activity is inhibited by sodium cyanide. Release of this cytoprotective factor was increased by differentiation stimuli and oxidative stress. Taken together, these results suggest that release of a hydrogen peroxide-reducing factor by PC12D cells increases cell tolerance against oxidative stress. This study provides new insights into the antioxidative properties of factors in extracellular fluid.

Microarray Analyses Reveal Marked Differences in Growth Factor and Receptor Expression Between 8-Cell Human Embryos and Pluripotent Stem Cells

PubMed Central

Vlismas, Antonis; Bletsa, Ritsa; Mavrogianni, Despina; Mamali, Georgina; Pergamali, Maria; Dinopoulou, Vasiliki; Partsinevelos, George; Drakakis, Peter; Loutradis, Dimitris

2016-01-01

Previous microarray analyses of RNAs from 8-cell (8C) human embryos revealed a lack of cell cycle checkpoints and overexpression of core circadian oscillators and cell cycle drivers relative to pluripotent human stem cells [human embryonic stem cells/induced pluripotent stem (hES/iPS)] and fibroblasts, suggesting growth factor independence during early cleavage stages. To explore this possibility, we queried our combined microarray database for expression of 487 growth factors and receptors. Fifty-one gene elements were overdetected on the 8C arrays relative to hES/iPS cells, including 14 detected at least 80-fold higher, which annotated to multiple pathways: six cytokine family (CSF1R, IL2RG, IL3RA, IL4, IL17B, IL23R), four transforming growth factor beta (TGFB) family (BMP6, BMP15, GDF9, ENG), one fibroblast growth factor (FGF) family [FGF14(FH4)], one epidermal growth factor member (GAB1), plus CD36, and CLEC10A. 8C-specific gene elements were enriched (73%) for reported circadian-controlled genes in mouse tissues. High-level detection of CSF1R, ENG, IL23R, and IL3RA specifically on the 8C arrays suggests the embryo plays an active role in blocking immune rejection and is poised for trophectoderm development; robust detection of NRG1, GAB1, -2, GRB7, and FGF14(FHF4) indicates novel roles in early development in addition to their known roles in later development. Forty-four gene elements were underdetected on the 8C arrays, including 11 at least 80-fold under the pluripotent cells: two cytokines (IFITM1, TNFRSF8), five TGFBs (BMP7, LEFTY1, LEFTY2, TDGF1, TDGF3), two FGFs (FGF2, FGF receptor 1), plus ING5, and WNT6. The microarray detection patterns suggest that hES/iPS cells exhibit suppressed circadian competence, underexpression of early differentiation markers, and more robust expression of generic pluripotency genes, in keeping with an artificial state of continual uncommitted cell division. In contrast, gene expression patterns of the 8C embryo suggest that

Saxagliptin Induces β-Cell Proliferation through Increasing Stromal Cell-Derived Factor-1α In Vivo and In Vitro.

PubMed

Li, Chun-Jun; Sun, Bei; Fang, Qian-Hua; Ding, Min; Xing, Yun-Zhi; Chen, Li-Ming; Yu, De-Min

2017-01-01

Dipeptidyl peptidase-4 inhibitors, such as saxagliptin, have been reported to have beneficial effects on β-cell function, but the specific underlying mechanism remains unclear. Stromal cell-derived factor-1α (SDF-1α), a chemokine produced in multiple organs, has been considered as a crucial regulator in promoting β-cell survival. Here, we speculate that SDF-1α might mediate the effect of saxagliptin on improving β-cell function. After 12-week saxagliptin treatment in high-fat diet/streptozotocin-induced diabetic rats, significant improvement in pancreas insulin secretion capacity evaluated by hyperglycemia clamp and increased β-cell to α-cell areas ratio were observed. Saxagliptin significantly induced β-cell proliferation and upregulated the expression of proliferation-related factors including c-myc and cyclind D1 determined with western blotting from the isolated islets. The expression/activity of DPP-4 was significantly reduced and paralleled with the restoration of SDF-1α levels in the saxagliptin-treated diabetic rats, subsequently the key WNT-signaling regulators, β-catenin, and AKT were activated. However, the effect of saxagliptin inducing β-cell proliferation was attenuated when we silenced the SDF-1α receptor (CXCR4) with RNAi in INS cell lines. Collectively, our data indicate that SDF-1α mediates the protective effect of saxagliptin on β-cell proliferation, suggesting that DPP-4 inhibitors have the potential role on delaying β-cell failure and SDF-1α could be a therapeutic target of β-cell regeneration.

Saxagliptin Induces β-Cell Proliferation through Increasing Stromal Cell-Derived Factor-1α In Vivo and In Vitro

PubMed Central

Li, Chun-Jun; Sun, Bei; Fang, Qian-Hua; Ding, Min; Xing, Yun-Zhi; Chen, Li-Ming; Yu, De-Min

2017-01-01

Dipeptidyl peptidase-4 inhibitors, such as saxagliptin, have been reported to have beneficial effects on β-cell function, but the specific underlying mechanism remains unclear. Stromal cell-derived factor-1α (SDF-1α), a chemokine produced in multiple organs, has been considered as a crucial regulator in promoting β-cell survival. Here, we speculate that SDF-1α might mediate the effect of saxagliptin on improving β-cell function. After 12-week saxagliptin treatment in high-fat diet/streptozotocin-induced diabetic rats, significant improvement in pancreas insulin secretion capacity evaluated by hyperglycemia clamp and increased β-cell to α-cell areas ratio were observed. Saxagliptin significantly induced β-cell proliferation and upregulated the expression of proliferation-related factors including c-myc and cyclind D1 determined with western blotting from the isolated islets. The expression/activity of DPP-4 was significantly reduced and paralleled with the restoration of SDF-1α levels in the saxagliptin-treated diabetic rats, subsequently the key WNT-signaling regulators, β-catenin, and AKT were activated. However, the effect of saxagliptin inducing β-cell proliferation was attenuated when we silenced the SDF-1α receptor (CXCR4) with RNAi in INS cell lines. Collectively, our data indicate that SDF-1α mediates the protective effect of saxagliptin on β-cell proliferation, suggesting that DPP-4 inhibitors have the potential role on delaying β-cell failure and SDF-1α could be a therapeutic target of β-cell regeneration. PMID:29230196

Cellular Factors Targeting APCs to Modulate Adaptive T Cell Immunity

PubMed Central

Do, Jeongsu; Min, Booki

2014-01-01

The fate of adaptive T cell immunity is determined by multiple cellular and molecular factors, among which the cytokine milieu plays the most important role in this process. Depending on the cytokines present during the initial T cell activation, T cells become effector cells that produce different effector molecules and execute adaptive immune functions. Studies thus far have primarily focused on defining how these factors control T cell differentiation by targeting T cells themselves. However, other non-T cells, particularly APCs, also express receptors for the factors and are capable of responding to them. In this review, we will discuss how APCs, by responding to those cytokines, influence T cell differentiation and adaptive immunity. PMID:25126585

The chromaffin cell: paradigm in cell, developmental and growth factor biology.

PubMed Central

Unsicker, K

1993-01-01

This article reviews the chromaffin cell in relation to studies that have elucidated fundamental phenomena in cell biology (the molecular anatomy of exocytosis) and developmental neuroscience (the principle of neuropoiesis in the development of the sympathoadrenal cell lineage). A final section addresses growth factor synthesis and storage in chromaffin cells and their implications for the treatment of neurological disorders, such as Parkinson's disease. Images Fig. 3 PMID:8300412

Application of stem cell/growth factor system, as a multimodal therapy approach in regenerative medicine to improve cell therapy yields.

PubMed

Pourrajab, Fatemeh; Babaei Zarch, Mojtaba; Baghi Yazdi, Mohammad; Rahimi Zarchi, Abolfazl; Vakili Zarch, Abbas

2014-04-15

Stem cells hold a great promise for regenerative medicine, especially for replacing cells in infarcted organ that hardly have any intrinsic renewal capacity, including heart and brain. Signaling pathways that regulate pluripotency or lineage-specific gene and protein expression have been the major focus of stem cell research. Between them, there are some well known signaling pathways such as GF/GFR systems, SDF-1α/CXC4 ligand receptor interaction and PI3K/Akt signaling, and cytokines may regulate cell fate decisions, and can be utilized to positively influence cell therapy outcomes or accentuate synergistic compliance. For example, contributing factors in the progression of heart failure are both the loss of cardiomyocytes after myocardial infarction, and the absence of an adequate endogenous repair signaling. Combining cell engraftment with therapeutic signaling factor delivery is more exciting in terms of host progenitor/donor stem cell survival and proliferation. Thus stem cell-based therapy, besides triggering signaling pathways through GF/GFR systems can become a realistic option in regenerative processes for replacing lost cells and reconstituting the damaged organ, as before. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Role of human oocyte-enriched factors in somatic cell reprograming.

PubMed

El-Gammal, Zaynab; AlOkda, Abdelrahman; El-Badri, Nagwa

2018-06-08

Cellular reprograming paves the way for creating functional patient-specific tissues to eliminate immune rejection responses by applying the same genetic profile. However, the epigenetic memory of a cell remains a challenge facing the current reprograming methods and does not allow transcription factors to bind properly. Because somatic cells can be reprogramed by transferring their nuclear contents into oocytes, introducing specific oocyte factors into differentiated cells is considered a promising approach for mimicking the reprograming process that occurs during fertilization. Mammalian metaphase II oocyte possesses a superior capacity to epigenetically reprogram somatic cell nuclei towards an embryonic stem cell-like state than the current factor-based reprograming approaches. This may be due to the presence of specific factors that are lacking in the current factor-based reprograming approaches. In this review, we focus on studies identifying human oocyte-enriched factors aiming to understand the molecular mechanisms mediating cellular reprograming. We describe the role of oocyte-enriched factors in metabolic switch, chromatin remodelling, and global epigenetic transformation. This is critical for improving the quality of resulting reprogramed cells, which is crucial for therapeutic applications. Copyright © 2018 Elsevier B.V. All rights reserved.

Cell-to-cell transmission of retroviruses: Innate immunity and interferon-induced restriction factors

PubMed Central

Jolly, Clare

2011-01-01

It has been known for some time that retroviruses can disseminate between immune cells either by conventional cell-free transmission or by directed cell-to-cell spread. Over the past few years there has been increasing interest in how retroviruses may use cell-to-cell spread to promote more rapid infection kinetics and circumvent humoral immunity. Effective humoral immune responses are intimately linked with innate immunity and the interplay between retroviruses and innate immunity is a rapidly expanding area of research that has been advanced considerably by the identification of cellular restriction factors that provide barriers to retroviral infection. The effect of innate immunity and restriction factors on retroviral cell-to-cell spread has been comparatively little studied; however recent work suggests this maybe changing. Here I will review some recent advances in what is a budding area of retroviral research. PMID:21247613

ETV5 transcription factor is overexpressed in ovarian cancer and regulates cell adhesion in ovarian cancer cells.

PubMed

Llauradó, Marta; Abal, Miguel; Castellví, Josep; Cabrera, Sílvia; Gil-Moreno, Antonio; Pérez-Benavente, Asumpció; Colás, Eva; Doll, Andreas; Dolcet, Xavier; Matias-Guiu, Xavier; Vazquez-Levin, Mónica; Reventós, Jaume; Ruiz, Anna

2012-04-01

Epithelial ovarian cancer is the most lethal gynecological malignancy and the fifth leading cause of cancer deaths in women in the Western world. ETS transcription factors are known to act as positive or negative regulators of the expression of genes that are involved in various biological processes, including those that control cellular proliferation, differentiation, apoptosis, tissue remodeling, angiogenesis and transformation. ETV5 belongs to the PEA3 subfamily. PEA3 subfamily members are able to activate the transcription of proteases, matrix metalloproteinases and tissue inhibitor of metalloproteases, which is central to both tumor invasion and angiogenesis. Here, we examined the role of the ETV5 transcription factor in epithelial ovarian cancer and we found ETV5 was upregulated in ovarian tumor samples compared to ovarian tissue controls. The in vitro inhibition of ETV5 decreased cell proliferation in serum-deprived conditions, induced EMT and cell migration and decreased cell adhesion to extracellular matrix components. ETV5 inhibition also decreased cell-cell adhesion and induced apoptosis in anchorage-independent conditions. Accordingly, upregulation of ETV5 induced the expression of cell adhesion molecules and enhanced cell survival in a spheroid model. Our findings suggest that the overexpression of ETV5 detected in ovarian cancer cells may contribute to ovarian tumor progression through the ability of ETV5 to enhance proliferation of ovarian cancer cells. In addition, upregulation of ETV5 would play a role in ovarian cancer cell dissemination and metastasis into the peritoneal cavity by protecting ovarian cancer cells from apoptosis and by increasing the adhesion of ovarian cancer cells to the peritoneal wall through the regulation of cell adhesion molecules. Copyright © 2011 UICC.

Pluripotency transcription factors and Tet1/2 maintain Brd4-independent stem cell identity.

PubMed

Finley, Lydia W S; Vardhana, Santosha A; Carey, Bryce W; Alonso-Curbelo, Direna; Koche, Richard; Chen, Yanyang; Wen, Duancheng; King, Bryan; Radler, Megan R; Rafii, Shahin; Lowe, Scott W; Allis, C David; Thompson, Craig B

2018-05-01

A robust network of transcription factors and an open chromatin landscape are hallmarks of the naive pluripotent state. Recently, the acetyllysine reader Brd4 has been implicated in stem cell maintenance, but the relative contribution of Brd4 to pluripotency remains unclear. Here, we show that Brd4 is dispensable for self-renewal and pluripotency of embryonic stem cells (ESCs). When maintained in their ground state, ESCs retain transcription factor binding and chromatin accessibility independent of Brd4 function or expression. In metastable ESCs, Brd4 independence can be achieved by increased expression of pluripotency transcription factors, including STAT3, Nanog or Klf4, so long as the DNA methylcytosine oxidases Tet1 and Tet2 are present. These data reveal that Brd4 is not essential for ESC self-renewal. Rather, the levels of pluripotency transcription factor abundance and Tet1/2 function determine the extent to which bromodomain recognition of protein acetylation contributes to the maintenance of gene expression and cell identity.

A serum factor promotes collagenase synthesis by an osteoblastic cell line

NASA Technical Reports Server (NTRS)

Puccinelli, J. M.; Omura, T. H.; Strege, D. W.; Jeffrey, J. J.; Partridge, N. C.

1991-01-01

Regulation of the synthesis of collagenase was investigated in the osteoblastic cell line, UMR 106-01. The cells were stained by the avidin-biotin-complex technique for the presence of the enzyme. By this method, it was possible to identify cells producing collagenase. Synthesis, but not secretion, was found to be constitutive in these cells with the enzyme located intracellularly in cytoplasmic vesicles and the Golgi apparatus. The amount of collagenase contained within UMR cells and the number of cells synthesizing the enzyme were proportional to the concentration of fetal bovine serum in the incubating medium. When serum was withdrawn from the osteosarcoma cells, the content of collagenase decreased with time and the enzyme became undetectable by 48 h of serum depletion. The decrease in collagenase content could be completely reversed by resupplying serum to the cells. The collagenase promoting activity of serum could not be eliminated by adsorption on activated charcoal but was retained by a dialysis membrane with a 12,000 mol wt cutoff. A range of bone-seeking hormones or agents known to affect collagenase secretion was added to the medium in an attempt to mimic the effect of serum on collagenase accumulation. None of these agonists, including parathyroid hormone, could reproduce the effect of serum on these cells, although parathyroid hormone could act as a collagenase secretagogue in the presence or absence of serum. It is concluded that fetal bovine serum contains a yet unidentified factor or factors greater than 12,000 mol wt responsible for the continued synthesis of collagenase by UMR 106-01 cells.

Transcription Factor IRF4 Promotes CD8+ T Cell Exhaustion and Limits the Development of Memory-like T Cells during Chronic Infection.

PubMed

Man, Kevin; Gabriel, Sarah S; Liao, Yang; Gloury, Renee; Preston, Simon; Henstridge, Darren C; Pellegrini, Marc; Zehn, Dietmar; Berberich-Siebelt, Friederike; Febbraio, Mark A; Shi, Wei; Kallies, Axel

2017-12-19

During chronic stimulation, CD8 + T cells acquire an exhausted phenotype characterized by expression of inhibitory receptors, down-modulation of effector function, and metabolic impairments. T cell exhaustion protects from excessive immunopathology but limits clearance of virus-infected or tumor cells. We transcriptionally profiled antigen-specific T cells from mice infected with lymphocytic choriomeningitis virus strains that cause acute or chronic disease. T cell exhaustion during chronic infection was driven by high amounts of T cell receptor (TCR)-induced transcription factors IRF4, BATF, and NFATc1. These regulators promoted expression of inhibitory receptors, including PD-1, and mediated impaired cellular metabolism. Furthermore, they repressed the expression of TCF1, a transcription factor required for memory T cell differentiation. Reducing IRF4 expression restored the functional and metabolic properties of antigen-specific T cells and promoted memory-like T cell development. These findings indicate that IRF4 functions as a central node in a TCR-responsive transcriptional circuit that establishes and sustains T cell exhaustion during chronic infection. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

SOXF factors regulate murine satellite cell self-renewal and function through inhibition of β-catenin activity.

PubMed

Alonso-Martin, Sonia; Auradé, Frédéric; Mademtzoglou, Despoina; Rochat, Anne; Zammit, Peter S; Relaix, Frédéric

2018-06-08

Muscle satellite cells are the primary source of stem cells for postnatal skeletal muscle growth and regeneration. Understanding genetic control of satellite cell formation, maintenance, and acquisition of their stem cell properties is on-going, and we have identified SOXF (SOX7, SOX17, SOX18) transcriptional factors as being induced during satellite cell specification. We demonstrate that SOXF factors regulate satellite cell quiescence, self-renewal and differentiation. Moreover, ablation of Sox17 in the muscle lineage impairs postnatal muscle growth and regeneration. We further determine that activities of SOX7, SOX17 and SOX18 overlap during muscle regeneration, with SOXF transcriptional activity requisite. Finally, we show that SOXF factors also control satellite cell expansion and renewal by directly inhibiting the output of β-catenin activity, including inhibition of Ccnd1 and Axin2 . Together, our findings identify a key regulatory function of SoxF genes in muscle stem cells via direct transcriptional control and interaction with canonical Wnt/β-catenin signaling. © 2018, Alonso-Martin et al.

Transcription factor interplay in T helper cell differentiation

PubMed Central

Evans, Catherine M.

2013-01-01

The differentiation of CD4 helper T cells into specialized effector lineages has provided a powerful model for understanding immune cell differentiation. Distinct lineages have been defined by differential expression of signature cytokines and the lineage-specifying transcription factors necessary and sufficient for their production. The traditional paradigm of differentiation towards Th1 and Th2 subtypes driven by T-bet and GATA3, respectively, has been extended to incorporate additional T cell lineages and transcriptional regulators. Technological advances have expanded our view of these lineage-specifying transcription factors to the whole genome and revealed unexpected interplay between them. From these data, it is becoming clear that lineage specification is more complex and plastic than previous models might have suggested. Here, we present an overview of the different forms of transcription factor interplay that have been identified and how T cell phenotypes arise as a product of this interplay within complex regulatory networks. We also suggest experimental strategies that will provide further insight into the mechanisms that underlie T cell lineage specification and plasticity. PMID:23878131

Transcription factor interplay in T helper cell differentiation.

PubMed

Evans, Catherine M; Jenner, Richard G

2013-11-01

The differentiation of CD4 helper T cells into specialized effector lineages has provided a powerful model for understanding immune cell differentiation. Distinct lineages have been defined by differential expression of signature cytokines and the lineage-specifying transcription factors necessary and sufficient for their production. The traditional paradigm of differentiation towards Th1 and Th2 subtypes driven by T-bet and GATA3, respectively, has been extended to incorporate additional T cell lineages and transcriptional regulators. Technological advances have expanded our view of these lineage-specifying transcription factors to the whole genome and revealed unexpected interplay between them. From these data, it is becoming clear that lineage specification is more complex and plastic than previous models might have suggested. Here, we present an overview of the different forms of transcription factor interplay that have been identified and how T cell phenotypes arise as a product of this interplay within complex regulatory networks. We also suggest experimental strategies that will provide further insight into the mechanisms that underlie T cell lineage specification and plasticity.

Evaluation of procoagulant tissue factor expression in canine hemangiosarcoma cell lines.

PubMed

Witter, Lauren E; Gruber, Erika J; Lean, Fabian Z X; Stokol, Tracy

2017-01-01

OBJECTIVE To evaluate expression of procoagulant tissue factor (TF) by canine hemangiosarcoma cells in vitro. SAMPLES 4 canine hemangiosarcoma cell lines (SB-HSA [mouse-passaged cutaneous tumor], Emma [primary metastatic brain tumor], and Frog and Dal-1 [primary splenic tumors]) and 1 nonneoplastic canine endothelial cell line (CnAoEC). PROCEDURES TF mRNA and TF antigen expression were evaluated by quantitative real-time PCR assay and flow cytometry, respectively. Thrombin generation was measured in canine plasma and in coagulation factor-replete or specific coagulation factor-deficient human plasma by calibrated automated thrombography. Corn trypsin inhibitor and annexin V were used to examine contributions of contact activation and membrane-bound phosphatidylserine, respectively, to thrombin generation. RESULTS All cell lines expressed TF mRNA and antigen, with significantly greater expression of both products in SB-HSA and Emma cells than in CnAoEC. A greater percentage of SB-HSA cells expressed TF antigen, compared with other hemangiosarcoma cell lines. All hemangiosarcoma cell lines generated significantly more thrombin than did CnAoEC in canine or factor-replete human plasma. Thrombin generation induced by SB-HSA cells was significantly lower in factor VII-deficient plasma than in factor-replete plasma and was abolished in factor X-deficient plasma; residual thrombin generation in factor VII-deficient plasma was abolished by incubation of cells with annexin V. Thrombin generation by SB-HSA cells was unaffected by the addition of corn trypsin inhibitor. CONCLUSIONS AND CLINICAL RELEVANCE Hemangiosarcoma cell lines expressed procoagulant TF in vitro. Further research is needed to determine whether TF can be used as a biomarker for hemostatic dysfunction in dogs with hemangiosarcoma.

Role of hepatocyte growth factor in the development of dendritic cells from CD34+ bone marrow cells.

PubMed

Ovali, E; Ratip, S; Kibaroglu, A; Tekelioglu, Y; Cetiner, M; Karti, S; Aydin, F; Bayik, M; Akoglu, T

2000-05-01

Hepatocyte growth factor (HGF) is known to augment the effects of stem cell factor, interleukin-3, granulocyte-macrophage colony-stimulating factor (GM-CSF), erythropoetin, and granulocyte colony-stimulating factor, all of which are involved in hematopoiesis. HGF is also known to have a role in immune responses. The aim of this study was to investigate whether HGF is involved in the development of dendritic cells (DC) from CD34+ bone marrow cells. CD34+ cells obtained from three healthy donors were incubated in various combinations of HGF, GM-CSF, and tumor necrosis factor (TNF) for 12 days. Developing cell populations were analyzed for surface markers, morphology and functional capacities by flow cytometry, light microscopy and mixed lymphocyte reaction, respectively. Incubation with HGF alone generated greater number of dendritic cells from CD34+ bone marrow cells than incubation with GM-CSF, or a combination of GM-CSF with TNF. HGF was also found to potentiate the effect of GM-CSF on DC and monocyte development. The effects of HGF were inhibited by the concurrent use of TNF. HGF appears to be a significant factor in the development of dendritic cells from CD34+ bone marrow cells.

3D Tracking of individual growth factor receptors on polarized cells

NASA Astrophysics Data System (ADS)

Werner, James; Stich, Dominik; Cleyrat, Cedric; Phipps, Mary; Wadinger-Ness, Angela; Wilson, Bridget

We have been developing methods for following 3D motion of selected biomolecular species throughout mammalian cells. Our approach exploits a custom designed confocal microscope that uses a unique spatial filter geometry and active feedback 200 times/second to follow fast 3D motion. By exploiting new non-blinking quantum dots as fluorescence labels, individual molecular trajectories can be observed for several minutes. We also will discuss recent instrument upgrades, including the ability to perform spinning disk fluorescence microscopy on the whole mammalian cell performed simultaneously with 3D molecular tracking experiments. These instrument upgrades were used to quantify 3D heterogeneous transport of individual growth factor receptors (EGFR) on live human renal cortical epithelial cells.

Fabrication of contacts for silicon solar cells including printing burn through layers

DOEpatents

Ginley, David S; Kaydanova, Tatiana; Miedaner, Alexander; Curtis, Calvin J; Van Hest, Marinus Franciscus Antonius Maria

2014-06-24

A method for fabricating a contact (240) for a solar cell (200). The method includes providing a solar cell substrate (210) with a surface that is covered or includes an antireflective coating (220). For example, the substrate (210) may be positioned adjacent or proximate to an outlet of an inkjet printer (712) or other deposition device. The method continues with forming a burn through layer (230) on the coating (220) by depositing a metal oxide precursor (e.g., using an inkjet or other non-contact printing method to print or apply a volume of liquid or solution containing the precursor). The method includes forming a contact layer (240) comprising silver over or on the burn through layer (230), and then annealing is performed to electrically connect the contact layer (240) to the surface of the solar cell substrate (210) through a portion of the burn through layer (230) and the coating (220).

Immunohistochemical expression of vascular endothelial growth factor in canine oral squamous cell carcinomas.

PubMed

Martano, Manuela; Restucci, Brunella; Ceccarelli, Dora Maria; Lo Muzio, Lorenzo; Maiolino, Paola

2016-01-01

Angiogenesis is crucial for the growth and metastasis of malignant tumours, and various proangiogenic factors promote this process. One of these factors is vascular endothelial growth factor (VEGF), which appears to play a key role in tumour angiogenesis. The aim of the present study was to assess whether VEGF expression is associated with angiogenesis, disease progression and neoplastic proliferation in canine oral squamous cell carcinoma (OSCC) tissue. VEGF immunoreactivity was quantified by immunohistochemistry in 30 specimens, including normal oral mucosa and OSCC tissues graded as well, moderately or poorly differentiated. VEGF expression was correlated with tumour cell proliferation, as assessed using the proliferating cell nuclear antigen (PCNA) marker and microvessel density (data already published). The present results revealed that VEGF and PCNA expression increased significantly between normal oral tissue and neoplastic tissue, and between well and moderately/poorly differentiated tumours. In addition, VEGF expression was strongly correlated with PCNA expression and microvessel density. It was concluded that VEGF may promote angiogenesis through a paracrine pathway, stimulating endothelial cell proliferation and, similarly, may induce tumour cell proliferation through an autocrine pathway. The present results suggest that the evaluation of VEGF may be a useful additional criterion for estimating malignancy and growth potential in canine OSCCs.

Engraftment of donor mesenchymal stem cells in chimeric BXSB includes vascular endothelial cells and hepatocytes.

PubMed

Jones, Olcay Y; Gok, Faysal; Rushing, Elisabeth J; Horkayne-Szakaly, Iren; Ahmed, Atif A

2011-01-01

Somatic tissue engraftment was studied in BXSB mice treated with mesenchymal stem cell transplantation. Hosts were conditioned with nonlethal radiation prior to introducing donor cells from major histocompatibility complex-matched green fluorescent protein transgenic mice. Transplant protocols differed for route of injection, ie, intravenous (i.v.) versus intraperitoneal (i.p.), and source of mesenchymal stem cells, ie, unfractionated bone marrow cells, ex vivo expanded mesenchymal stem cells, or bone chips. Tissue chimerism was determined after short (10-12 weeks) or long (62 weeks) posttransplant follow-up by immunohistochemistry for green fluorescent protein. Engraftment of endothelial cells was seen in several organs including liver sinusoidal cells in i.v. treated mice with ex vivo expanded mesenchymal stem cells or with unfractionated bone marrow cells. Periportal engraftment of liver hepatocytes, but not engraftment of endothelial cells, was found in mice injected i.p. with bone chips. Engraftment of adipocytes was a common denominator in both i.v. and i.p. routes and occurred during early phases post-transplant. Disease control was more robust in mice that received both i.v. bone marrow and i.p. bone chips compared to mice that received i.v. bone marrow alone. Thus, the data support potential use of mesenchymal stem cell transplant for treatment of severe lupus. Future studies are needed to optimize transplant conditions and tailor protocols that may in part be guided by fat and endothelial biomarkers. Furthermore, the role of liver chimerism in disease control and the nature of cellular communication among donor hematopoietic and mesenchymal stem cells in a chimeric host merit further investigation.

Regulation of cell growth by redox-mediated extracellular proteolysis of platelet-derived growth factor receptor beta.

PubMed

Okuyama, H; Shimahara, Y; Kawada, N; Seki, S; Kristensen, D B; Yoshizato, K; Uyama, N; Yamaoka, Y

2001-07-27

Redox-regulated processes are important elements in various cellular functions. Reducing agents, such as N-acetyl-l-cysteine (NAC), are known to regulate signal transduction and cell growth through their radical scavenging action. However, recent studies have shown that reactive oxygen species are not always involved in ligand-stimulated intracellular signaling. Here, we report a novel mechanism by which NAC blocks platelet-derived growth factor (PDGF)-induced signaling pathways in hepatic stellate cells, a fibrogenic player in the liver. Unlike in vascular smooth muscle cells, we found that reducing agents, including NAC, triggered extracellular proteolysis of PDGF receptor-beta, leading to desensitization of hepatic stellate cells toward PDGF-BB. This effect was mediated by secreted mature cathepsin B. In addition, type II transforming growth factor-beta receptor was also down-regulated. Furthermore, these events seemed to cause a dramatic improvement of rat liver fibrosis. These results indicated that redox processes impact the cell's response to growth factors by regulating the turnover of growth factor receptors and that "redox therapy" is promising for fibrosis-related disease.

Transcription factor Etv5 is essential for the maintenance of alveolar type II cells.

PubMed

Zhang, Zhen; Newton, Kim; Kummerfeld, Sarah K; Webster, Joshua; Kirkpatrick, Donald S; Phu, Lilian; Eastham-Anderson, Jeffrey; Liu, Jinfeng; Lee, Wyne P; Wu, Jiansheng; Li, Hong; Junttila, Melissa R; Dixit, Vishva M

2017-04-11

Alveolar type II (AT2) cell dysfunction contributes to a number of significant human pathologies including respiratory distress syndrome, lung adenocarcinoma, and debilitating fibrotic diseases, but the critical transcription factors that maintain AT2 cell identity are unknown. Here we show that the E26 transformation-specific (ETS) family transcription factor Etv5 is essential to maintain AT2 cell identity. Deletion of Etv5 from AT2 cells produced gene and protein signatures characteristic of differentiated alveolar type I (AT1) cells. Consistent with a defect in the AT2 stem cell population, Etv5 deficiency markedly reduced recovery following bleomycin-induced lung injury. Lung tumorigenesis driven by mutant KrasG12D was also compromised by Etv5 deficiency. ERK activation downstream of Ras was found to stabilize Etv5 through inactivation of the cullin-RING ubiquitin ligase CRL4 COP1/DET1 that targets Etv5 for proteasomal degradation. These findings identify Etv5 as a critical output of Ras signaling in AT2 cells, contributing to both lung homeostasis and tumor initiation.

The bias of experimental design, including strain background, in the determination of critical Streptococcus suis serotype 2 virulence factors

PubMed Central

Auger, Jean-Philippe; Chuzeville, Sarah; Roy, David; Mathieu-Denoncourt, Annabelle; Xu, Jianguo; Grenier, Daniel

2017-01-01

Streptococcus suis serotype 2 is an important porcine bacterial pathogen and emerging zoonotic agent mainly responsible for sudden death, septic shock, and meningitis. However, serotype 2 strains are genotypically and phenotypically heterogeneous. Though a multitude of virulence factors have been described for S. suis serotype 2, the lack of a clear definition regarding which ones are truly “critical” has created inconsistencies that have only recently been highlighted. Herein, the involvement of two factors previously described as being critical for S. suis serotype 2 virulence, whether the dipeptidyl peptidase IV and autolysin, were evaluated with regards to different ascribed functions using prototype strains belonging to important sequence types. Results demonstrate a lack of reproducibility with previously published data. In fact, the role of the dipeptidyl peptidase IV and autolysin as critical virulence factors could not be confirmed. Though certain in vitro functions may be ascribed to these factors, their roles are not unique for S. suis, probably due to compensation by other factors. As such, variations and discrepancies in experimental design, including in vitro assays, cell lines, and animal models, are an important source of differences between results. Moreover, the use of different sequence types in this study demonstrates that the role attributed to a virulence factor may vary according to the S. suis serotype 2 strain background. Consequently, it is necessary to establish standard experimental designs according to the experiment and purpose in order to facilitate comparison between laboratories. Alongside, studies should include strains of diverse origins in order to prevent erroneous and biased conclusions that could affect future studies. PMID:28753679

Electrolytic/fuel cell bundles and systems including a current collector in communication with an electrode thereof

DOEpatents

Hawkes, Grant L.; Herring, James S.; Stoots, Carl M.; O& #x27; Brien, James E.

2013-03-05

Electrolytic/fuel cell bundles and systems including such bundles include an electrically conductive current collector in communication with an anode or a cathode of each of a plurality of cells. A cross-sectional area of the current collector may vary in a direction generally parallel to a general direction of current flow through the current collector. The current collector may include a porous monolithic structure. At least one cell of the plurality of cells may include a current collector that surrounds an outer electrode of the cell and has at least six substantially planar exterior surfaces. The planar surfaces may extend along a length of the cell, and may abut against a substantially planar surface of a current collector of an adjacent cell. Methods for generating electricity and for performing electrolysis include flowing current through a conductive current collector having a varying cross-sectional area.

Glial cell line-derived neurotrophic factor and endothelial cells promote self-renewal of rabbit germ cells with spermatogonial stem cell properties.

PubMed

Kubota, Hiroshi; Wu, Xin; Goodyear, Shaun M; Avarbock, Mary R; Brinster, Ralph L

2011-08-01

Previous studies suggest that exogenous factors crucial for spermatogonial stem cell (SSC) self-renewal are conserved among several mammalian species. Since glial cell line-derived neurotrophic factor (GDNF) and fibroblast growth factor 2 (FGF2) are critical for rodent SSC self-renewal, we hypothesized that they might promote self-renewal of nonrodent SSCs. Therefore, we cultured testicular germ cells from prepubertal rabbits in the presence of GDNF and FGF2 and found they proliferated indefinitely as cellular clumps that displayed characteristics previously identified for rodent SSCs. The rabbit germ cells could not be maintained on mouse embryonic fibroblast (STO) feeders that support rodent SSC self-renewal in vitro but were rather supported on mouse yolk sac-derived endothelial cell (C166) feeder layers. Proliferation of rabbit germ cells was dependent on GDNF. Of critical importance was that clump-forming rabbit germ cells colonized seminiferous tubules of immunodeficient mice, proliferated for at least 6 mo, while retaining an SSC phenotype in the testes of recipient mice, indicating that they were rabbit SSCs. This study demonstrates that GDNF is a mitogenic factor promoting self-renewal that is conserved between rodent and rabbit SSCs; with an evolutionary separation of ∼ 60 million years. These findings provide a foundation to study the mechanisms governing SSC self-renewal in nonrodent species.

The Role of the Stem Cell Factor/c-kit Complex in Neurofibrormatosis.

DTIC Science & Technology

1997-10-01

investigations of the Kit/ stem cell factor complex in hyperplasias of these cells. In the request for no-cost extension, several experiments were listed to be...soluble stem cell factor from the NF1 knockout Schwann cells. We also found that most neural tumors express mRNA for Kit, and also for stem cell factor.

Endothelial cell stimulating angiogenesis factor.

PubMed

Weiss, J B; McLaughlin, B

1998-04-01

Endothelial cell stimulating angiogenesis factor (ESAF) is a small (> 1000 Da) dialysable non-peptide molecule with potent angiogenic activity. ESAF activates the major pro-matrix metalloproteinases and also uniquely reactivates the complex of these active enzymes with their tissue inhibitors resulting in both active enzyme and inhibitor. These actions may be pivotal in its role as an angiogenic factor. ESAF is primarily involved in angiogenic conditions where inflammatory cells are not evident such as foetal bone growth and electrically stimulated skeletal muscles and proliferative retinopathy. However, high levels also occur in actively growing human intracranial tumours but it is not noticeably elevated in rheumatoid arthritic synovial fluid. Its extreme potency and low molecular mass make its structural determination difficult. Possible therapeutic applications would be in the treatment of ischaemic ulcers, acceleration of fracture repair, infertility and more modestly in the correction of baldness. Analogues of ESAF could be of value in treating angiogenic diseases such as psoriasis and proliferative retinopathy.

Anterior pituitary cells defective in the cell-autonomous factor, df, undergo cell lineage specification but not expansion.

PubMed

Gage, P J; Roller, M L; Saunders, T L; Scarlett, L M; Camper, S A

1996-01-01

The Ames dwarf mouse transmits a recessive mutation (df) resulting in a profound anterior pituitary hypocellularity due to a general lack of thyrotropes, somatotropes and lactotropes. These cell types are also dependent on the pituitary-specific transcription factor, Pit-1. We present evidence that expression of Pit-1 and limited commitment to these cells lineages occurs in df/df pituitaries. Thus, the crucial role of df may be in lineage-specific proliferation, rather than cytodifferentiation. The presence of all three Pit-1-dependent cell types in clonally derived clusters provides compelling evidence that these three lineages share a common, pluripotent precursor cell. Clusters containing different combinations of Pit-1-dependent cell types suggests that the Pit-1+ precursor cells choose from multiple developmental options during ontogeny. Characterization of df/df<-->+/+ chimeric mice demonstrated that df functions by a cell-autonomous mechanism. Therefore, df and Pit-1 are both cell-autonomous factors required for thyrotrope, somatotrope and lactotrope ontogeny, but their relative roles are different.

Tumor necrosis factor-alpha inhibits stem cell factor-induced proliferation of human bone marrow progenitor cells in vitro. Role of p55 and p75 tumor necrosis factor receptors.

PubMed Central

Rusten, L S; Smeland, E B; Jacobsen, F W; Lien, E; Lesslauer, W; Loetscher, H; Dubois, C M; Jacobsen, S E

1994-01-01

Stem cell factor (SCF), a key regulator of hematopoiesis, potently synergizes with a number of hematopoietic growth factors. However, little is known about growth factors capable of inhibiting the actions of SCF. TNF-alpha has been shown to act as a bidirectional regulator of myeloid cell proliferation and differentiation. This study was designed to examine interactions between TNF-alpha and SCF. Here, we demonstrate that TNF-alpha potently and directly inhibits SCF-stimulated proliferation of CD34+ hematopoietic progenitor cells. Furthermore, TNF-alpha blocked all colony formation stimulated by SCF in combination with granulocyte colony-stimulating factor (CSF) or CSF-1. The synergistic effect of SCF observed in combination with GM-CSF or IL-3 was also inhibited by TNF-alpha, resulting in colony numbers similar to those obtained in the absence of SCF. These effects of TNF-alpha were mediated through the p55 TNF receptor, whereas little or no inhibition was signaled through the p75 TNF receptor. Finally, TNF-alpha downregulated c-kit cell-surface expression on CD34+ bone marrow cells, and this was predominantly a p55 TNF receptor-mediated event as well. Images PMID:7518828

Enhanced CDC of B cell chronic lymphocytic leukemia cells mediated by rituximab combined with a novel anti-complement factor H antibody.

PubMed

Winkler, Mark T; Bushey, Ryan T; Gottlin, Elizabeth B; Campa, Michael J; Guadalupe, Eross S; Volkheimer, Alicia D; Weinberg, J Brice; Patz, Edward F

2017-01-01

Rituximab therapy for B cell chronic lymphocytic leukemia (B-CLL) has met with mixed success. Among several factors to which resistance can be attributed is failure to activate complement dependent cytotoxicity (CDC) due to protective complement regulatory proteins, including the soluble regulator complement factor H (CFH). We hypothesized that rituximab killing of non-responsive B-CLL cells could be augmented by a novel human monoclonal antibody against CFH. The B cells from 11 patients with B-CLL were tested ex vivo in CDC assays with combinations of CFH monoclonal antibody, rituximab, and a negative control antibody. CDC of rituximab non-responsive malignant B cells from CLL patients could in some cases be augmented by the CFH monoclonal antibody. Antibody-mediated cytotoxicity of cells was dependent upon functional complement. In one case where B-CLL cells were refractory to CDC by the combination of rituximab plus CFH monoclonal antibody, additionally neutralizing the membrane complement regulatory protein CD59 allowed CDC to occur. Inhibiting CDC regulatory proteins such as CFH holds promise for overcoming resistance to rituximab therapy in B-CLL.

Insulin-like growth factor-1 signaling in renal cell carcinoma.

PubMed

Tracz, Adam F; Szczylik, Cezary; Porta, Camillo; Czarnecka, Anna M

2016-07-12

Renal cell carcinoma (RCC) incidence is highest in highly developed countries and it is the seventh most common neoplasm diagnosed. RCC management include nephrectomy and targeted therapies. Type 1 insulin-like growth factor (IGF-1) pathway plays an important role in cell proliferation and apoptosis resistance. IGF-1 and insulin share overlapping downstream signaling pathways in normal and cancer cells. IGF-1 receptor (IGF1R) stimulation may promote malignant transformation promoting cell proliferation, dedifferentiation and inhibiting apoptosis. Clear cell renal cell carcinoma (ccRCC) patients with IGF1R overexpression have 70 % increased risk of death compared to patients who had tumors without IGF1R expression. IGF1R signaling deregulation may results in p53, WT, BRCA1, VHL loss of function. RCC cells with high expression of IGF1R are more resistant to chemotherapy than cells with low expression. Silencing of IGF1R increase the chemosensitivity of ccRCC cells and the effect is greater in VHL mutated cells. Understanding the role of IGF-1 signaling pathway in RCC may result in development of new targeted therapeutic interventions. First preclinical attempts with anti-IGF-1R monoclonal antibodies or fragment antigen-binding (Fab) fragments alone or in combination with an mTOR inhibitor were shown to inhibit in vitro growth and reduced the number of colonies formed by of RCC cells.

Conditioned media from a renal cell carcinoma cell line demonstrates the presence of basic fibroblast growth factor.

PubMed

Mydlo, J H; Zajac, J; Macchia, R J

1993-09-01

In a previous report, we demonstrated the isolation and purification of a heparin binding growth factor from human renal carcinoma, and suggested that this growth factor may play a role in the neovascularity and growth of the tumor. In this report, we demonstrate that the growth of the renal cell carcinoma cell line RC29 is stimulated by the addition of exogenous fibroblast growth factor (FGF), epidermal growth factor (EGF) and transforming growth factor alpha (TGF alpha). Also, media conditioned by this cell line was able to stimulate growth of the A431 vulvar tumor cell line, known for its high concentration of EGF receptors, 3T3 fibroblasts, human umbilical vein (HUV) cells and RC29 cells. Using heparin-sepharose chromatography and then SDS polyacrylamide gel electrophoresis (PAGE), we were able to demonstrate several proteins in the conditioned media of the RC29 cell line. Using Western blot analysis, we detected that at least one of the proteins expressed in this conditioned media was FGF and that it belongs to the basic, not acidic, family of fibroblast growth factors. These findings suggest that renal tumors may express growth factors that may play a direct role in maintaining their unrestricted proliferation.

Effect of Irrigation Time of Antiseptic Solutions on Bone Cell Viability and Growth Factor Release.

PubMed

Sawada, Kosaku; Nakahara, Ken; Haga-Tsujimura, Maiko; Fujioka-Kobayashi, Masako; Iizuka, Tateyuki; Miron, Richard J

2018-03-01

Antiseptic solutions are commonly utilized to treat local infection in the oral and maxillofacial region. However, surrounding vital bone is also exposed to antiseptic agents during irrigation and may have a potential negative impact on bone survival. The aim of the present study was therefore to investigate the effect of rinsing time with various antiseptic solutions on bone cell viability, as well as their subsequent release of growth factors important for bone regeneration. The bone samples collected from porcine mandible were rinsed in the following commonly utilized antiseptic solutions; povidone-iodine (0.5%), chlorhexidine digluconate (CHX, 0.2%), hydrogen peroxide (1%), and sodium hypochlorite (0.25%) for 1, 5, 10, 20, 30, or 60 minutes and assessed for cell viability and release of growth factors including vascular endothelial growth factor, transforming growth factor beta 1, bone morphogenetic protein 2, receptor activator of nuclear factor kappa-B ligand, and interleukin-1 beta by enzyme-linked immunosorbent assay. It was found in all the tested groups that the long exposure of any of the tested antiseptic solutions drastically promoted higher cell death. Sodium hypochlorite demonstrated the significantly highest cell death and at all time points. Interestingly, bone cell viability was highest in the CHX group post short-term rinsing of 1, 5, or 10 minutes when compared with the other 4 tested groups. A similar trend was also observed in subsequent growth factor release. The present study demonstrated that of the 4 tested antiseptic solutions, short-term CHX rinsing (ideally within 1 minute) favored bone cell viability and growth factor release. Clinical protocols should be adapted accordingly.

hCG-dependent regulation of angiogenic factors in human granulosa lutein cells.

PubMed

Phan, B; Rakenius, A; Pietrowski, D; Bettendorf, H; Keck, C; Herr, D

2006-07-01

As prerequisite for development and maintenance of many diseases angiogenesis is of particular interest in medicine. Pathologic angiogenesis takes place in chronic arthritis, collagen diseases, arteriosclerosis, retinopathy associated with diabetes, and particularly in cancers. However, angiogenesis as a physiological process regularly occurs in the ovary. After ovulation the corpus luteum is formed by rapid vascularization of initially avascular granulosa lutein cell tissue. This process is regulated by gonadotropic hormones. In order to gain further insights in the regulatory mechanisms of angiogenesis in the ovary, we investigated these mechanisms in cell culture of human granulosa lutein cells. In particular, we determined the expression and production of several angiogenic factors including tissue inhibitor of matrix metalloproteinases-1 (TIMP-1), Leptin, connective tissue growth factor (CTGF), meningioma-associated complimentary DNA (Mac25), basic fibroblast growth factor (bFGF), and Midkine. In addition, we showed that human chorionic gonadotropin (hCG) has distinct effects on their expression and production. hCG enhances the expression and production of TIMP-1, whereas it downregulates the expression of CTGF and Mac25. Furthermore it decreases the expression of Leptin. Our results provide evidence that hCG determines growth and development of the corpus luteum by mediating angiogenic pathways in human granulosa lutein cells. Hence we describe a further approach to understand the regulation of angiogenesis in the ovary.

Streptococcus pyogenes CAMP factor attenuates phagocytic activity of RAW 264.7 cells.

PubMed

Kurosawa, Mie; Oda, Masataka; Domon, Hisanori; Saitoh, Issei; Hayasaki, Haruaki; Terao, Yutaka

2016-02-01

Streptococcus pyogenes produces molecules that inhibit the function of human immune system, thus allowing the pathogen to grow and spread in tissues. It is known that S. pyogenes CAMP factor increases erythrocytosis induced by Staphylococcus aureus β-hemolysin. However, the effects of CAMP factor for immune cells are unclear. In this study, we investigated the effects of CAMP factor to macrophages. Western blotting analysis demonstrated that all examined strains expressed CAMP factor protein. In the presence of calcium or magnesium ion, CAMP factor was significantly released in the supernatant. In addition, both culture supernatant from S. pyogenes strain SSI-9 and recombinant CAMP factor dose-dependently induced vacuolation in RAW 264.7 cells, but the culture supernatant from Δcfa isogenic mutant strain did not. CAMP factor formed oligomers in RAW 264.7 cells in a time-dependent manner. CAMP factor suppressed cell proliferation via G2 phase cell cycle arrest without inducing cell death. Furthermore, CAMP factor reduced the uptake of S. pyogenes and phagocytic activity indicator by RAW 264.7 cells. These results suggest that CAMP factor works as a macrophage dysfunction factor. Therefore, we conclude that CAMP factor allows S. pyogenes to escape the host immune system, and contribute to the spread of streptococcal infection. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Human mesenchymal stem cells cultured on silk hydrogels with variable stiffness and growth factor differentiate into mature smooth muscle cell phenotype.

PubMed

Floren, Michael; Bonani, Walter; Dharmarajan, Anirudh; Motta, Antonella; Migliaresi, Claudio; Tan, Wei

2016-02-01

Cell-matrix and cell-biomolecule interactions play critical roles in a diversity of biological events including cell adhesion, growth, differentiation, and apoptosis. Evidence suggests that a concise crosstalk of these environmental factors may be required to direct stem cell differentiation toward matured cell type and function. However, the culmination of these complex interactions to direct stem cells into highly specific phenotypes in vitro is still widely unknown, particularly in the context of implantable biomaterials. In this study, we utilized tunable hydrogels based on a simple high pressure CO2 method and silk fibroin (SF) the structural protein of Bombyx mori silk fibers. Modification of SF protein starting water solution concentration results in hydrogels of variable stiffness while retaining key structural parameters such as matrix pore size and β-sheet crystallinity. To further resolve the complex crosstalk of chemical signals with matrix properties, we chose to investigate the role of 3D hydrogel stiffness and transforming growth factor (TGF-β1), with the aim of correlating the effects on the vascular commitment of human mesenchymal stem cells. Our data revealed the potential to upregulate matured vascular smooth muscle cell phenotype (myosin heavy chain expression) of hMSCs by employing appropriate matrix stiffness and growth factor (within 72h). Overall, our observations suggest that chemical and physical stimuli within the cellular microenvironment are tightly coupled systems involved in the fate decisions of hMSCs. The production of tunable scaffold materials that are biocompatible and further specialized to mimic tissue-specific niche environments will be of considerable value to future tissue engineering platforms. This article investigates the role of silk fibroin hydrogel stiffness and transforming growth factor (TGF-β1), with the aim of correlating the effects on the vascular commitment of human mesenchymal stem cells. Specifically, we

Cellular localization and expression of template-activating factor I in different cell types.

PubMed

Nagata, K; Saito, S; Okuwaki, M; Kawase, H; Furuya, A; Kusano, A; Hanai, N; Okuda, A; Kikuchi, A

1998-05-01

Template-activating factors I (TAF-I) alpha and beta have been identified as chromatin remodeling factors from human HeLa cells. TAF-I beta corresponds to the protein encoded by the set gene, which was found in an acute undifferentiated leukemia as a fusion version with the can gene via chromosomal translocation. To determine the localization of TAF-I, we raised both polyclonal and monoclonal antibodies against TAF-I. The proteins that react to the antibodies are present not only in human cells but also in mouse, frog, insect, and yeast cells. The mouse TAF-I homologue is ubiquitous in a variety of tissue cells, including liver, kidney, spleen, lung, heart, and brain. It is of interest that the amounts of TAF-I alpha and beta vary among hemopoietic cells and some specific cell types do not contain TAF-I alpha. The level of the TAF-I proteins does not change significantly during the cell cycle progression in either HeLa cells synchronized with an excess concentration of thymidine or NIH 3T3 cells released from the serum-depleted state. TAF-I is predominantly located in nuclei, while TAF-I that is devoid of its acidic region, the region which is essential for the TAF-I activity, shows both nuclear and cytoplasmic localization. The localization of TAF-I in conjunction with the regulation of its activity is discussed.

Improving poor fill factors for solar cells via light-induced plating

NASA Astrophysics Data System (ADS)

Zhao, Xing; Rui, Jia; Wuchang, Ding; Yanlong, Meng; Zhi, Jin; Xinyu, Liu

2012-09-01

Silicon solar cells are prepared following the conventional fabrication processes, except for the metallization firing process. The cells are divided into two groups with higher and lower fill factors, respectively. After light-induced plating (LIP), the fill factors of the solar cells in both groups with different initial values reach the same level. Scanning electron microscope (SEM) images are taken under the bulk silver electrodes, which prove that the improvement for cells with a poor factor after LIP should benefit from sufficient exploitation of the high density silver crystals formed during the firing process. Moreover, the application of LIP to cells with poor electrode contact performance, such as nanowire cells and radial junction solar cells, is proposed.

Casein kinase 2 and the cell response to growth factors.

PubMed

Filhol-Cochet, O; Loue-Mackenbach, P; Cochet, C; Chambaz, E M

1994-01-01

Different approaches have been followed with the aim of delineating a possible role of casein kinase 2 (CK2) in the mitogenic signalling in response to cell growth factors. (a) Immunocytochemical detection of CK2 showed that while the kinase is evenly distributed throughout cycle arrested cells, it becomes preferentially associated with the nuclear compartment in activity growing cells; (b) CK2 biosynthesis is activated as an early response of quiescent cells to growth factors. The newly synthesized CK2 steadily accumulates as the cells progress through the G1 phase. This growth factor-induced CK2 biosynthesis involves in parallel the two alpha and beta subunits of the kinase, with no detectable preferential subcellular localization of the newly synthesized enzyme; and (c) In addition to substrate phosphorylation, CK2 may form molecular complexes with cell components of functional significance. Such is the case with the protein p53, a major negative regulator of the cell cycle. CK2 forms a high affinity association (Kd 70 nM) with p53, through its beta subunit. The complex dissociates in the presence of adenosine triphosphate (ATP). These observations suggest that CK2 and p53 may play a coordinated regulatory role in the cell response to growth factors.

Angiocrine factors from Akt-activated endothelial cells balance self-renewal and differentiation of haematopoietic stem cells

PubMed Central

Kobayashi, Hideki; Butler, Jason M.; O'Donnell, Rebekah; Kobayashi, Mariko; Ding, Bi-Sen; Bonner, Bryant; Chiu, Vi K.; Nolan, Daniel J.; Shido, Koji; Benjamin, Laura; Rafii, Shahin

2010-01-01

Endothelial cells establish an instructive vascular niche that reconstitutes haematopoietic stem and progenitor cells (HSPCs) through release of specific paracrine growth factors, known as angiocrine factors. However, the mechanism by which endothelial cells balance the rate of proliferation and lineage-specific differentiation of HSPCs is unknown. Here, we demonstrate that Akt activation in endothelial cells, through recruitment of mTOR, but not the FoxO pathway, upregulates specific angiocrine factors that support expansion of CD34−Flt3− KLS HSPCs with long-term haematopoietic stem cell (LT-HSC) repopulation capacity. Conversely, co-activation of Akt-stimulated endothelial cells with p42/44 MAPK shifts the balance towards maintenance and differentiation of the HSPCs. Selective activation of Akt1 in the endothelial cells of adult mice increased the number of colony forming units in the spleen and CD34−Flt3− KLS HSPCs with LT-HSC activity in the bone marrow, accelerating haematopoietic recovery. Therefore, the activation state of endothelial cells modulates reconstitution of HSPCs through the upregulation of angiocrine factors, with Akt–mTOR-activated endothelial cells supporting the self-renewal of LT-HSCs and expansion of HSPCs, whereas MAPK co-activation favours maintenance and lineage-specific differentiation of HSPCs. PMID:20972423

Neural Stem Cell Differentiation Using Microfluidic Device-Generated Growth Factor Gradient.

PubMed

Kim, Ji Hyeon; Sim, Jiyeon; Kim, Hyun-Jung

2018-04-11

Neural stem cells (NSCs) have the ability to self-renew and differentiate into multiple nervous system cell types. During embryonic development, the concentrations of soluble biological molecules have a critical role in controlling cell proliferation, migration, differentiation and apoptosis. In an effort to find optimal culture conditions for the generation of desired cell types in vitro , we used a microfluidic chip-generated growth factor gradient system. In the current study, NSCs in the microfluidic device remained healthy during the entire period of cell culture, and proliferated and differentiated in response to the concentration gradient of growth factors (epithermal growth factor and basic fibroblast growth factor). We also showed that overexpression of ASCL1 in NSCs increased neuronal differentiation depending on the concentration gradient of growth factors generated in the microfluidic gradient chip. The microfluidic system allowed us to study concentration-dependent effects of growth factors within a single device, while a traditional system requires multiple independent cultures using fixed growth factor concentrations. Our study suggests that the microfluidic gradient-generating chip is a powerful tool for determining the optimal culture conditions.

Priming Dental Pulp Stem Cells With Fibroblast Growth Factor-2 Increases Angiogenesis of Implanted Tissue-Engineered Constructs Through Hepatocyte Growth Factor and Vascular Endothelial Growth Factor Secretion

PubMed Central

Gorin, Caroline; Rochefort, Gael Y.; Bascetin, Rumeyza; Ying, Hanru; Lesieur, Julie; Sadoine, Jérémy; Beckouche, Nathan; Berndt, Sarah; Novais, Anita; Lesage, Matthieu; Hosten, Benoit; Vercellino, Laetitia; Merlet, Pascal; Le-Denmat, Dominique; Marchiol, Carmen; Letourneur, Didier; Nicoletti, Antonino; Vital, Sibylle Opsahl; Poliard, Anne; Salmon, Benjamin; Germain, Stéphane

2016-01-01

Tissue engineering strategies based on implanting cellularized biomaterials are promising therapeutic approaches for the reconstruction of large tissue defects. A major hurdle for the reliable establishment of such therapeutic approaches is the lack of rapid blood perfusion of the tissue construct to provide oxygen and nutrients. Numerous sources of mesenchymal stem cells (MSCs) displaying angiogenic potential have been characterized in the past years, including the adult dental pulp. Establishment of efficient strategies for improving angiogenesis in tissue constructs is nevertheless still an important challenge. Hypoxia was proposed as a priming treatment owing to its capacity to enhance the angiogenic potential of stem cells through vascular endothelial growth factor (VEGF) release. The present study aimed to characterize additional key factors regulating the angiogenic capacity of such MSCs, namely, dental pulp stem cells derived from deciduous teeth (SHED). We identified fibroblast growth factor-2 (FGF-2) as a potent inducer of the release of VEGF and hepatocyte growth factor (HGF) by SHED. We found that FGF-2 limited hypoxia-induced downregulation of HGF release. Using three-dimensional culture models of angiogenesis, we demonstrated that VEGF and HGF were both responsible for the high angiogenic potential of SHED through direct targeting of endothelial cells. In addition, FGF-2 treatment increased the fraction of Stro-1+/CD146+ progenitor cells. We then applied in vitro FGF-2 priming to SHED before encapsulation in hydrogels and in vivo subcutaneous implantation. Our results showed that FGF-2 priming is more efficient than hypoxia at increasing SHED-induced vascularization compared with nonprimed controls. Altogether, these data demonstrate that FGF-2 priming enhances the angiogenic potential of SHED through the secretion of both HGF and VEGF. Significance The results from the present study show that fibroblast growth factor-2 (FGF-2) priming is more

Empirical Derivation of Correction Factors for Human Spiral Ganglion Cell Nucleus and Nucleolus Count Units.

PubMed

Robert, Mark E; Linthicum, Fred H

2016-01-01

Profile count method for estimating cell number in sectioned tissue applies a correction factor for double count (resulting from transection during sectioning) of count units selected to represent the cell. For human spiral ganglion cell counts, we attempted to address apparent confusion between published correction factors for nucleus and nucleolus count units that are identical despite the role of count unit diameter in a commonly used correction factor formula. We examined a portion of human cochlea to empirically derive correction factors for the 2 count units, using 3-dimensional reconstruction software to identify double counts. The Neurotology and House Histological Temporal Bone Laboratory at University of California at Los Angeles. Using a fully sectioned and stained human temporal bone, we identified and generated digital images of sections of the modiolar region of the lower first turn of cochlea, identified count units with a light microscope, labeled them on corresponding digital sections, and used 3-dimensional reconstruction software to identify double-counted count units. For 25 consecutive sections, we determined that double-count correction factors for nucleus count unit (0.91) and nucleolus count unit (0.92) matched the published factors. We discovered that nuclei and, therefore, spiral ganglion cells were undercounted by 6.3% when using nucleolus count units. We determined that correction factors for count units must include an element for undercounting spiral ganglion cells as well as the double-count element. We recommend a correction factor of 0.91 for the nucleus count unit and 0.98 for the nucleolus count unit when using 20-µm sections. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2015.

Effect of rituximab on B cell phenotype and serum B cell-activating factor levels in patients with thrombotic thrombocytopenic purpura

PubMed Central

Becerra, E; Scully, M A; Leandro, M J; Heelas, E O; Westwood, J-P; De La Torre, I; Cambridge, G

2015-01-01

Autoantibodies inhibiting the activity of the metalloproteinase, ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13), underlie the pathogenesis of thrombotic thrombocytopenic purpura (TTP). Rituximab (RTX) combined with plasma-exchange (PEX) is an effective treatment in TTP. Patients can remain in remission for extended periods following PEX/RTX, and this is associated with continuing reduction in antibodies to ADAMTS13. Factors controlling B cell differentiation to autoantibody production, including stimulation through the B cell receptor and interactions with the B cell-activating factor (BAFF), may thus impact length of remission. In this cross-sectional study, we measured naive and memory B cell phenotypes [using CD19/immunoglobulin (Ig)D/CD27] following PEX/RTX treatment in TTP patients at B cell return (n = 6) and in 12 patients in remission 10–68 months post-RTX. We also investigated relationships among serum BAFF, soluble CD23 (sCD23– a surrogate measure of acquiring B memory (CD27+) phenotype) and BAFF receptor (BAFF-R) expression. At B cell return after PEX/RTX, naive B cells predominated and BAFF-R expression was reduced compared to healthy controls (P < 0·001). In the remission group, despite numbers of CD19+ B cells within normal limits in most patients, the percentage and absolute numbers of pre-switch and memory B cells remained low, with sCD23 levels at the lower end of the normal range. BAFF levels were correlated inversely with BAFF-R expression and time after therapy. In conclusion, the long-term effects of RTX therapy in patients with TTP included slow regeneration of memory B cell subsets and persistently reduced BAFF-R expression across all B cell subpopulations. This may reflect the delay in selection and differentiation of potentially autoreactive (ADAMTS13-specific) B cells, resulting in relatively long periods of low disease activity after therapy. PMID:25339550

A Novel Technique to Follow Consequences of Exogenous Factors, Including Therapeutic Drugs, on Living Human Breast Epithelial Cells

DTIC Science & Technology

1999-07-01

and lipid vectors, are being tested. Concurrent with the development of procedures for live - cell imaging , we are examining the distribution of proteins...dimensional matrix. These studies have not yet begun. There are a number of procedures that must be developed and perfected in the live - cell imaging , as...components of the Wnt signaling pathway are too preliminary and require additional research prior to publication. (9) CONCLUSIONS Live cell imaging of

Vectorology and Factor Delivery in Induced Pluripotent Stem Cell Reprogramming

PubMed Central

2014-01-01

Induced pluripotent stem cell (iPSC) reprogramming requires sustained expression of multiple reprogramming factors for a limited period of time (10–30 days). Conventional iPSC reprogramming was achieved using lentiviral or simple retroviral vectors. Retroviral reprogramming has flaws of insertional mutagenesis, uncontrolled silencing, residual expression and re-activation of transgenes, and immunogenicity. To overcome these issues, various technologies were explored, including adenoviral vectors, protein transduction, RNA transfection, minicircle DNA, excisable PiggyBac (PB) transposon, Cre-lox excision system, negative-sense RNA replicon, positive-sense RNA replicon, Epstein-Barr virus-based episomal plasmids, and repeated transfections of plasmids. This review provides summaries of the main vectorologies and factor delivery systems used in current reprogramming protocols. PMID:24625220

Oxidative stress increases eukaryotic initiation factor 4E phosphorylation in vascular cells.

PubMed Central

Duncan, Roger F; Peterson, Hazel; Hagedorn, Curt H; Sevanian, Alex

2003-01-01

Dysregulated cell growth can be caused by increased activity of protein synthesis eukaryotic initiation factor (eIF) 4E. Dysregulated cell growth is also characteristic of atherosclerosis. It is postulated that exposure of vascular cells, such as endothelial cells, smooth muscle cells and monocytes/macrophages, to oxidants, such as oxidized low-density lipoprotein (oxLDL), leads to the elaboration of growth factors and cytokines, which in turn results in smooth muscle cell hyperproliferation. To investigate whether activation of eIF4E might play a role in this hyperproliferative response, vascular cells were treated with oxLDL, oxidized lipid components of oxLDL and several model oxidants, including H(2)O(2) and dimethyl naphthoquinone. Exposure to each of these compounds led to a dose- and time-dependent increase in eIF4E phosphorylation in all three types of vascular cells, correlated with a modest increase in overall translation rate. No changes in eIF4EBP, eIF2 or eIF4B modification state were observed. Increased eIF4E phosphorylation was paralleled by increased presence of eIF4E in high-molecular-mass protein complexes characteristic of its most active form. Anti-oxidants at concentrations typically employed to block oxidant-induced cell signalling likewise promoted eIF4E phosphorylation. The results of this study indicate that increased eIF4E activity may contribute to the pathophysiological events in early atherogenesis by increasing the expression of translationally inefficient mRNAs encoding growth-promoting proteins. PMID:12215171

Parent education and biologic factors influence on cognition in sickle cell anemia

PubMed Central

King, Allison A.; Strouse, John J.; Rodeghier, Mark J.; Compas, Bruce E.; Casella, James F.; McKinstry, Robert C.; Noetzel, Michael J.; Quinn, Charles T.; Ichord, Rebecca; Dowling, Michael M.; Miller, J. Philip; DeBaun, Michael R.

2015-01-01

Children with sickle cell anemia have a high prevalence of silent cerebral infarcts (SCIs) that are associated with decreased full-scale intelligence quotient (FSIQ). While the educational attainment of parents is a known strong predictor of the cognitive development of children in general, the role of parental education in sickle cell anemia along with other factors that adversely affect cognitive function (anemia, cerebral infarcts) is not known. We tested the hypothesis that both the presence of SCI and parental education would impact FSIQ in children with sickle cell anemia. A multicenter, cross-sectional study was conducted in 19 US sites of the Silent Infarct Transfusion Trial among children with sickle cell anemia, age 5–15 years. All were screened for SCIs. Participants with and without SCI were administered the Wechsler Abbreviated Scale of Intelligence. A total of 150 participants (107 with and 43 without SCIs) were included in the analysis. In a multivariable linear regression model for FSIQ, the absence of college education for the head of household was associated with a decrease of 6.2 points (P=0.005); presence of SCI with a 5.2 point decrease (P=0.017); each $1000 of family income per capita with a 0.33 point increase (P=0.023); each increase of 1 year in age with a 0.96 point decrease (P=0.023); and each 1% (absolute) decrease in hemoglobin oxygen saturation with 0.75 point decrease (P=0.030). In conclusion, FSIQ in children with sickle cell anemia is best accounted for by a multivariate model that includes both biologic and socioenvironmental factors. PMID:24123128

Production of Multiple Growth Factors by a Newly Established Human Thyroid Carcinoma Cell Line

PubMed Central

Yoshida, Yataro; Ohashi, Kensaku; Sano, Emiko; Kobayashi, Hisataka; Endo, Keigo; Naruto, Masanobu; Nakamura, Toru

1992-01-01

A multiple growth factor‐producing tumor cell line (NIM‐1) was newly established from a patient with thyroid cancer and remarkable neutrophilia. NIM‐1 cells also caused severe neutrophilia in nude mice bearing tumors. NIM‐1‐conditioned medium (NIM‐1CM) contained activities that supported not only granulocyte, macrophage and eosinophil colony formation of human bone marrow cells but also the growth of colony‐stimulating factor (CSF)‐dependent cell lines, NFS60‐KX and TF‐1. Northern blot hybridization analysis revealed the constitutive expression of granulocyte‐CSF (G‐CSF), granulocyte/macrophage‐CSF (GM‐CSF) and interleukin(IL)‐6 mRNAs in NIM‐1 cells. Enzyme‐linked immunosorbent assays (ELISA) using NIM‐1CM also confirmed the production of IL‐la and a small amount of IL‐1β besides G‐CSF, GM‐CSF and IL‐6 in NIM‐1 cells. In addition, unexpected production of IL‐11 in NIM‐1 cells was detected by northern blot hybridization analysis and by bioassay using an IL‐11‐dependent cell line. Therefore, NIM‐1 cell line is shown to produce multiple cytokines including potentially megakaryopoietic growth factors such as GM‐CSF, IL‐6 and IL‐11. PMID:1372885

Mesenchymal stem cells derived from human exocrine pancreas express transcription factors implicated in beta-cell development.

PubMed

Baertschiger, Reto M; Bosco, Domenico; Morel, Philippe; Serre-Beinier, Veronique; Berney, Thierry; Buhler, Leo H; Gonelle-Gispert, Carmen

2008-07-01

Transplantation of in vitro generated islets or insulin-producing cells represents an attractive option to overcome organ shortage. The aim of this study was to isolate, expand, and characterize cells from human exocrine pancreas and analyze their potential to differentiate into beta cells. Fibroblast-like cells growing out of human exocrine tissue were characterized by flow cytometry and by their capacity to differentiate into mesenchymal cell lineages. During cell expansion and after differentiation toward beta cells, expression of transcription factors of endocrine pancreatic progenitors was analyzed by reverse transcription polymerase chain reaction. Cells emerged from 14/18 human pancreatic exocrine fractions and were expanded up to 40 population doublings. These cells displayed surface antigens similar to mesenchymal stem cells from bone marrow. A culture of these cells in adipogenic and chondrogenic differentiation media allowed differentiation into adipocyte- and chondrocyte-like cells. During expansion, cells expressed transcription factors implicated in islet development such as Isl1, Nkx2.2, Nkx6.1, nestin, Ngn3, Pdx1, and NeuroD. Activin A and hepatocyte growth factor induced an expression of insulin, glucagon, and glucokinase. Proliferating cells with characteristics of mesenchymal stem cells and endocrine progenitors were isolated from exocrine tissue. Under specific conditions, these cells expressed little insulin. Human pancreatic exocrine tissue might thus be a source of endocrine cell progenitors.

Emerging growth factor receptor antagonists for the treatment of renal cell carcinoma.

PubMed

Zahoor, Haris; Rini, Brian I

2016-12-01

The landscape of systemic treatment for metastatic renal cell carcinoma (RCC) has dramatically changed with the introduction of targeted agents including vascular endothelial growth factor (VEGF) inhibitors. Recently, multiple new agents including growth factor receptor antagonists and a checkpoint inhibitor were approved for the treatment of refractory metastatic RCC based on encouraging benefit shown in clinical trials. Areas covered: The background and biological rationale of existing treatment options including a brief discussion of clinical trials which led to their approval, is presented. This is followed by reviewing the limitations of these therapeutic options, medical need to develop new treatments and major goals of ongoing research. We then discuss two recently approved growth factor receptor antagonists i.e. cabozantinib and lenvatinib, and a recently approved checkpoint inhibitor, nivolumab, and issues pertaining to drug development, and future directions in treatment of metastatic RCC. Expert opinion: Recently approved growth factor receptor antagonists have shown encouraging survival benefit but associated drug toxicity is a major issue. Nivolumab, a programmed death 1 (PD-1) checkpoint inhibitor, has similarly shown survival benefit and is well tolerated. With multiple options now available in this patient population, the right sequence of these agents remains to be determined.

Epidermal growth factor-like growth factors prevent apoptosis of alcohol-exposed human placental cytotrophoblast cells.

PubMed

Wolff, Garen S; Chiang, Po Jen; Smith, Susan M; Romero, Roberto; Armant, D Randall

2007-07-01

Maternal alcohol abuse during pregnancy can produce an array of birth defects comprising fetal alcohol syndrome. A hallmark of fetal alcohol syndrome is intrauterine growth retardation, which is associated with elevated apoptosis of placental cytotrophoblast cells. Using a human first trimester cytotrophoblast cell line, we examined the relationship between exposure to ethanol and cytotrophoblast survival, as well as the ameliorating effects of epidermal growth factor (EGF)-like growth factors produced by human cytotrophoblast cells. After exposure to 0-100 mM ethanol, cell death was quantified by the TUNEL method, and expression of the nuclear proliferation marker, Ki67, was measured by immunohistochemistry. The mode of cell death was determined by assessing annexin V binding, caspase 3 activation, pyknotic nuclear morphology, reduction of TUNEL by caspase inhibition, and cellular release of lactate dehydrogenase. Ethanol significantly reduced proliferation and increased cell death approximately 2.5-fold through the apoptotic pathway within 1-2 h of exposure to 50 mM alcohol. Exposure to 25-50 mM ethanol significantly increased transforming growth factor alpha (TGFA) and heparin-binding EGF-like growth factor (HBEGF), but not EGF or amphiregulin (AREG). When cytotrophoblasts were exposed concurrently to 100 mM ethanol and 1 nM HBEGF or TGFA, the increase in apoptosis was prevented, while EGF ameliorated at 10 nM and AREG was weakly effective. HBEGF survival-promoting activity required ligation of either of its cognate receptors, HER1 or HER4. These findings reveal the potential for ethanol to rapidly induce cytotrophoblast apoptosis. However, survival factor induction could provide cytotrophoblasts with an endogenous cytoprotective mechanism.

Cardiomyocyte-released factors stimulate oligodendrocyte precursor cells proliferation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuroda, Mariko; Muramatsu, Rieko; Precursory Research for Embryonic Science and Technology

The heart produces multiple diffusible factors that are involved in a number of physiological processes, but the action of these factors on the central nervous system is not well understood. In this study, we found that one or more factors released by cardiomyocytes promote oligodendrocyte precursor cell (OPC) proliferation in vitro. Mouse OPCs co-cultured with mouse cardiomyocytes showed higher proliferative ability than OPCs cultured alone. In addition, cardiomyocyte-conditioned media was sufficient to promote OPC proliferation. The phosphorylation of phosphatidylinositol (PI) 3-kinase and extracellular signal-regulated kinase (ERK) in OPCs is necessary for the enhancement of OPC proliferation by cardiomyocyte-conditioned media. These datamore » indicate that heart-derived factors have the ability to directly regulate the function of central nervous system (CNS) cells.« less

Cyclic strain alters the expression and release of angiogenic factors by human tendon cells.

PubMed

Mousavizadeh, Rouhollah; Khosravi, Shahram; Behzad, Hayedeh; McCormack, Robert G; Duronio, Vincent; Scott, Alex

2014-01-01

Angiogenesis is associated with the tissue changes underlying chronic overuse tendinopathy. We hypothesized that repetitive, cyclic loading of human tendon cells would lead to increased expression and activity of angiogenic factors. We subjected isolated human tendon cells to overuse tensile loading using an in vitro model (1 Hz, 10% equibiaxial strain). We found that mechanically stimulated human tendon cells released factors that promoted in vitro proliferation and tube formation by human umbilical vein endothelial cells (HUVEC). In response to cyclic strain, there was a transient increase in the expression of several angiogenic genes including ANGPTL4, FGF-2, COX-2, SPHK1, TGF-alpha, VEGF-A and VEGF-C, with no change in anti-angiogenic genes (BAI1, SERPINF1, THBS1 and 2, TIMP1-3). Cyclic strain also resulted in the extracellular release of ANGPTL4 protein by tendon cells. Our study is the first report demonstrating the induction of ANGPTL4 mRNA and release of ANGPTL4 protein in response to cyclic strain. Tenocytes may contribute to the upregulation of angiogenesis during the development of overuse tendinopathy.

Cyclic Strain Alters the Expression and Release of Angiogenic Factors by Human Tendon Cells

PubMed Central

Mousavizadeh, Rouhollah; Khosravi, Shahram; Behzad, Hayedeh; McCormack, Robert G.; Duronio, Vincent; Scott, Alex

2014-01-01

Angiogenesis is associated with the tissue changes underlying chronic overuse tendinopathy. We hypothesized that repetitive, cyclic loading of human tendon cells would lead to increased expression and activity of angiogenic factors. We subjected isolated human tendon cells to overuse tensile loading using an in vitro model (1 Hz, 10% equibiaxial strain). We found that mechanically stimulated human tendon cells released factors that promoted in vitro proliferation and tube formation by human umbilical vein endothelial cells (HUVEC). In response to cyclic strain, there was a transient increase in the expression of several angiogenic genes including ANGPTL4, FGF-2, COX-2, SPHK1, TGF-alpha, VEGF-A and VEGF-C, with no change in anti-angiogenic genes (BAI1, SERPINF1, THBS1 and 2, TIMP1-3). Cyclic strain also resulted in the extracellular release of ANGPTL4 protein by tendon cells. Our study is the first report demonstrating the induction of ANGPTL4 mRNA and release of ANGPTL4 protein in response to cyclic strain. Tenocytes may contribute to the upregulation of angiogenesis during the development of overuse tendinopathy. PMID:24824595

Differential requirements for the Ets transcription factor Elf-1 in the development of NKT cells and NK cells

PubMed Central

Choi, Hak-Jong; Geng, Yanbiao; Cho, Hoonsik; Li, Sha; Giri, Pramod Kumar; Felio, Kyrie

2011-01-01

E26 Transformation specific (Ets) family transcription factors control the expression of a large number of genes regulating hematopoietic cell development and function. Two such transcription factors, Ets-1 and myeloid Elf-1–like factor (MEF), have been shown to play critical roles in both natural killer (NK)– and NKT-cell development, but not in the development of conventional T cells. In this study, we address the role of E74-like factor 1 (Elf-1), another Ets family transcription factor that is closely related to MEF but divergent from Ets-1, in NK- and NKT-cell development using Elf-1–deficient (Elf-1−/−) mice. Whereas the proportion of NK cells in Elf-1−/− mice was normal, the proportion of NKT cells was significantly reduced in the thymus and periphery of Elf-1−/− mice compared with wild-type (WT) mice. Although Ets-1–deficient mice lack NKT cells altogether, Elf-1−/− mice exhibited only a partial block in NKT-cell development caused by a cell-intrinsic defect in the selection, survival, and maturation of NKT cells. In addition, residual NKT cells found in Elf-1−/− mice produced less cytokine upon antigen stimulation compared with WT NKT cells. Our data demonstrate that Elf-1 plays an important and nonredundant role in the development and function of NKT cells, but is not involved in NK-cell development. PMID:21148815

Sulbutiamine counteracts trophic factor deprivation induced apoptotic cell death in transformed retinal ganglion cells.

PubMed

Kang, Kui Dong; Majid, Aman Shah Abdul; Kim, Kyung-A; Kang, Kyungsu; Ahn, Hong Ryul; Nho, Chu Won; Jung, Sang Hoon

2010-11-01

Sulbutiamine is a highly lipid soluble synthetic analogue of vitamin B(1) and is used clinically for the treatment of asthenia. The aim of our study was to demonstrate whether sulbutiamine is able to attenuate trophic factor deprivation induced cell death to transformed retinal ganglion cells (RGC-5). Cells were subjected to serum deprivation for defined periods and sulbutiamine at different concentrations was added to the cultures. Various procedures (e.g. cell viability assays, apoptosis assay, reactive oxygen species analysis, Western blot analysis, flow cytometric analysis, glutathione (GSH) and glutathione-S-transferase (GST) measurement) were used to demonstrate the effect of sulbutiamine. Sulbutiamine dose-dependently attenuated apoptotic cell death induced by serum deprivation and stimulated GSH and GST activity. Moreover, sulbutiamine decreased the expression of cleaved caspase-3 and AIF. This study demonstrates for the first time that sulbutiamine is able to attenuate trophic factor deprivation induced apoptotic cell death in neuronal cells in culture.

Epigenome Aberrations: Emerging Driving Factors of the Clear Cell Renal Cell Carcinoma

PubMed Central

Mehdi, Ali; Riazalhosseini, Yasser

2017-01-01

Clear cell renal cell carcinoma (ccRCC), the most common form of Kidney cancer, is characterized by frequent mutations of the von Hippel-Lindau (VHL) tumor suppressor gene in ~85% of sporadic cases. Loss of pVHL function affects multiple cellular processes, among which the activation of hypoxia inducible factor (HIF) pathway is the best-known function. Constitutive activation of HIF signaling in turn activates hundreds of genes involved in numerous oncogenic pathways, which contribute to the development or progression of ccRCC. Although VHL mutations are considered as drivers of ccRCC, they are not sufficient to cause the disease. Recent genome-wide sequencing studies of ccRCC have revealed that mutations of genes coding for epigenome modifiers and chromatin remodelers, including PBRM1, SETD2 and BAP1, are the most common somatic genetic abnormalities after VHL mutations in these tumors. Moreover, recent research has shed light on the extent of abnormal epigenome alterations in ccRCC tumors, including aberrant DNA methylation patterns, abnormal histone modifications and deregulated expression of non-coding RNAs. In this review, we discuss the epigenetic modifiers that are commonly mutated in ccRCC, and our growing knowledge of the cellular processes that are impacted by them. Furthermore, we explore new avenues for developing therapeutic approaches based on our knowledge of epigenome aberrations of ccRCC. PMID:28812986

Epigenome Aberrations: Emerging Driving Factors of the Clear Cell Renal Cell Carcinoma.

PubMed

Mehdi, Ali; Riazalhosseini, Yasser

2017-08-16

Clear cell renal cell carcinoma (ccRCC), the most common form of Kidney cancer, is characterized by frequent mutations of the von Hippel-Lindau ( VHL ) tumor suppressor gene in ~85% of sporadic cases. Loss of pVHL function affects multiple cellular processes, among which the activation of hypoxia inducible factor (HIF) pathway is the best-known function. Constitutive activation of HIF signaling in turn activates hundreds of genes involved in numerous oncogenic pathways, which contribute to the development or progression of ccRCC. Although VHL mutations are considered as drivers of ccRCC, they are not sufficient to cause the disease. Recent genome-wide sequencing studies of ccRCC have revealed that mutations of genes coding for epigenome modifiers and chromatin remodelers, including PBRM1 , SETD2 and BAP1 , are the most common somatic genetic abnormalities after VHL mutations in these tumors. Moreover, recent research has shed light on the extent of abnormal epigenome alterations in ccRCC tumors, including aberrant DNA methylation patterns, abnormal histone modifications and deregulated expression of non-coding RNAs. In this review, we discuss the epigenetic modifiers that are commonly mutated in ccRCC, and our growing knowledge of the cellular processes that are impacted by them. Furthermore, we explore new avenues for developing therapeutic approaches based on our knowledge of epigenome aberrations of ccRCC.

Mesenchymal Stem Cells Suppress Chronic Rejection in Heterotopic Small Intestine Transplant Rat Models Via Inhibition of CD68, Transforming Growth Factor- β1, and Platelet-Derived Growth Factor Expression.

PubMed

Li, Fuxin; Cao, Jisen; Zhao, Zhicheng; Li, Chuan; Qi, Feng; Liu, Tong

2017-04-01

Mesenchymal stem cells are easy to obtain and expand, with characteristics of low immunogenicity and strong tissue repair capacity. In this study, our aim was to investigate the role of mesenchymal stem cells in chronic immune rejection of heterotopic small intestine transplant in rats. After successfully constructing a rat chronic immune rejection model of heterotopic small intestine transplant, we infused mesenchymal stem cells into the animal recipients. We observed mesenchymal stem cell location in the recipients, recipient survival, pathology changes, and the expression of CD68, transforming growth factor β1, and platelet-derived growth factor C in the donor intestine. Mesenchymal stem cells inhibited the lymphocyte proliferation caused by concanavalin A in vitro. After stem cells were infused into recipients, they were mainly located in the donor intestine, as well as in the spleen and thymus. Recovery after transplant and pathology changes of the donor intestine in rats with stem cell infusion were better than in the control group; however, we observed no differences in survival time, accompanied by downregulated expression of CD68, transforming growth factor β1, and platelet-derived growth factor C. Mesenchymal stem cells, to a certain extent, could inhibit the process of chronic rejection. The mechanisms may include the inhibited function of these cells on lymphocyte proliferation, reduced infiltration of macrophages, and reduced expression of transforming growth factor β1 and platelet-derived growth factor C.

Qualitative models of seat discomfort including static and dynamic factors.

PubMed

Ebe, K; Griffin, M J

2000-06-01

Judgements of overall seating comfort in dynamic conditions sometimes correlate better with the static characteristics of a seat than with measures of the dynamic environment. This study developed qualitative models of overall seat discomfort to include both static and dynamic seat characteristics. A dynamic factor that reflected how vibration discomfort increased as vibration magnitude increased was combined with a static seat factor which reflected seating comfort without vibration. The ability of the model to predict the relative and overall importance of dynamic and static seat characteristics on comfort was tested in two experiments. A paired comparison experiment, using four polyurethane foam cushions (50, 70, 100, 120 mm thick), provided different static and dynamic comfort when 12 subjects were exposed to one-third octave band random vertical vibration with centre frequencies of 2.5 and 5.5 Hz, at magnitudes of 0.00, 0.25 and 0.50 m x s(-2) rms measured beneath the foam samples. Subject judgements of the relative discomfort of the different conditions depended on both static and dynamic characteristics in a manner consistent with the model. The effect of static and dynamic seat factors on overall seat discomfort was investigated by magnitude estimation using three foam cushions (of different hardness) and a rigid wooden seat at six vibration magnitudes with 20 subjects. Static seat factors (i.e. cushion stiffness) affected the manner in which vibration influenced the overall discomfort: cushions with lower stiffness were more comfortable and more sensitive to changes in vibration magnitude than those with higher stiffness. The experiments confirm that judgements of overall seat discomfort can be affected by both the static and dynamic characteristics of a seat, with the effect depending on vibration magnitude: when vibration magnitude was low, discomfort was dominated by static seat factors; as the vibration magnitude increased, discomfort became dominated

Targeting cancer stem cell plasticity through modulation of epidermal growth factor and insulin-like growth factor receptor signaling in head and neck squamous cell cancer.

PubMed

Leong, Hui Sun; Chong, Fui Teen; Sew, Pui Hoon; Lau, Dawn P; Wong, Bernice H; Teh, Bin-Tean; Tan, Daniel S W; Iyer, N Gopalakrishna

2014-09-01

Emerging data suggest that cancer stem cells (CSCs) exist in equilibrium with differentiated cells and that stochastic transitions between these states can account for tumor heterogeneity and drug resistance. The aim of this study was to establish an in vitro system that recapitulates stem cell plasticity in head and neck squamous cell cancers (HNSCCs) and identify the factors that play a role in the maintenance and repopulation of CSCs. Tumor spheres were established using patient-derived cell lines via anchorage-independent cell culture techniques. These tumor spheres were found to have higher aldehyde dehydrogenase (ALD) cell fractions and increased expression of Kruppel-like factor 4, SRY (sex determining region Y)-box 2, and Nanog and were resistant to γ-radiation, 5-fluorouracil, cisplatin, and etoposide treatment compared with monolayer culture cells. Monolayer cultures were subject to single cell cloning to generate clones with high and low ALD fractions. ALDHigh clones showed higher expression of stem cell and epithelial-mesenchymal transition markers compared with ALDLow clones. ALD fractions, representing stem cell fractions, fluctuated with serial passaging, equilibrating at a level specific to each cell line, and could be augmented by the addition of epidermal growth factor (EGF) and/or insulin. ALDHigh clones showed increased EGF receptor (EGFR) and insulin-like growth factor-1 receptor (IGF-1R) phosphorylation, with increased activation of downstream pathways compared with ALDLow clones. Importantly, blocking these pathways using specific inhibitors against EGFR and IGF-1R reduced stem cell fractions drastically. Taken together, these results show that HNSCC CSCs exhibit plasticity, with the maintenance of the stem cell fraction dependent on the EGFR and IGF-1R pathways and potentially amenable to targeted therapeutics. ©AlphaMed Press.

Induction of Epstein-Barr Virus Oncoprotein LMP1 by Transcription Factors AP-2 and Early B Cell Factor

PubMed Central

Noda, Chieko; Narita, Yohei; Watanabe, Takahiro; Yoshida, Masahiro; Ashio, Keiji; Sato, Yoshitaka; Goshima, Fumi; Kanda, Teru; Yoshiyama, Hironori; Tsurumi, Tatsuya; Kimura, Hiroshi

2016-01-01

ABSTRACT Latent membrane protein 1 (LMP1) is a major oncogene essential for primary B cell transformation by Epstein-Barr virus (EBV). Previous studies suggested that some transcription factors, such as PU.1, RBP-Jκ, NF-κB, and STAT, are involved in this expression, but the underlying mechanism is unclear. Here, we identified binding sites for PAX5, AP-2, and EBF in the proximal LMP1 promoter (ED-L1p). We first confirmed the significance of PU.1 and POU domain transcription factor binding for activation of the promoter in latency III. We then focused on the transcription factors AP-2 and early B cell factor (EBF). Interestingly, among the three AP-2-binding sites in the LMP1 promoter, two motifs were also bound by EBF. Overexpression, knockdown, and mutagenesis in the context of the viral genome indicated that AP-2 plays an important role in LMP1 expression in latency II in epithelial cells. In latency III B cells, on the other hand, the B cell-specific transcription factor EBF binds to the ED-L1p and activates LMP1 transcription from the promoter. IMPORTANCE Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) is crucial for B cell transformation and oncogenesis of other EBV-related malignancies, such as nasopharyngeal carcinoma and T/NK lymphoma. Its expression is largely dependent on the cell type or condition, and some transcription factors have been implicated in its regulation. However, these previous reports evaluated the significance of specific factors mostly by reporter assay. In this study, we prepared point-mutated EBV at the binding sites of such transcription factors and confirmed the importance of AP-2, EBF, PU.1, and POU domain factors. Our results will provide insight into the transcriptional regulation of the major oncogene LMP1. PMID:26819314

Evaluation of procoagulant tissue factor expression in canine hemangiosarcoma cell lines

PubMed Central

Witter, Lauren E.; Gruber, Erika J.; Lean, Fabian Z. X.; Stokol, Tracy

2017-01-01

OBJECTIVE To evaluate expression of procoagulant tissue factor (TF) by canine hemangiosarcoma cells in vitro. SAMPLES 4 canine hemangiosarcoma cell lines (SB-HSA [mouse-passaged cutaneous tumor], Emma [primary metastatic brain tumor], and Frog and Dal-1 [primary splenic tumors]) and 1 nonneoplastic canine endothelial cell line (CnAoEC). PROCEDURES TF mRNA and TF antigen expression were evaluated by quantitative real-time PCR assay and flow cytometry, respectively. Thrombin generation was measured in canine plasma and in coagulation factor–replete or specific coagulation factor–deficient human plasma by calibrated automated thrombography. Corn trypsin inhibitor and annexin V were used to examine contributions of contact activation and membrane-bound phosphatidylserine, respectively, to thrombin generation. RESULTS All cell lines expressed TF mRNA and antigen, with significantly greater expression of both products in SB-HSA and Emma cells than in CnAoEC. A greater percentage of SB-HSA cells expressed TF antigen, compared with other hemangiosarcoma cell lines. All hemangiosarcoma cell lines generated significantly more thrombin than did CnAoEC in canine or factor-replete human plasma. Thrombin generation induced by SB-HSA cells was significantly lower in factor VII-deficient plasma than in factor-replete plasma and was abolished in factor X–deficient plasma; residual thrombin generation in FVII-deficient plasma was abolished by incubation of cells with annexin V. Thrombin generation by SB-HSA cells was unaffected by the addition of corn trypsin inhibitor. CONCLUSIONS AND CLINICAL RELEVANCE Hemangiosarcoma cell lines expressed procoagulant TF in vitro. Further research is needed to determine whether TF can be used as a biomarker for hemostatic dysfunction in dogs with hemangiosarcoma. PMID:28029283

Identification of factors that function in Drosophila salivary gland cell death during development using proteomics

PubMed Central

McPhee, C K; Balgley, B M; Nelson, C; Hill, J H; Batlevi, Y; Fang, X; Lee, C S; Baehrecke, E H

2013-01-01

Proteasome inhibitors induce cell death and are used in cancer therapy, but little is known about the relationship between proteasome impairment and cell death under normal physiological conditions. Here, we investigate the relationship between proteasome function and larval salivary gland cell death during development in Drosophila. Drosophila larval salivary gland cells undergo synchronized programmed cell death requiring both caspases and autophagy (Atg) genes during development. Here, we show that ubiquitin proteasome system (UPS) function is reduced during normal salivary gland cell death, and that ectopic proteasome impairment in salivary gland cells leads to early DNA fragmentation and salivary gland condensation in vivo. Shotgun proteomic analyses of purified dying salivary glands identified the UPS as the top category of proteins enriched, suggesting a possible compensatory induction of these factors to maintain proteolysis during cell death. We compared the proteome following ectopic proteasome impairment to the proteome during developmental cell death in salivary gland cells. Proteins that were enriched in both populations of cells were screened for their function in salivary gland degradation using RNAi knockdown. We identified several factors, including trol, a novel gene CG11880, and the cop9 signalsome component cop9 signalsome 6, as required for Drosophila larval salivary gland degradation. PMID:22935612

Prosurvival Factors Improve Functional Engraftment of Myogenically Converted Dermal Cells into Dystrophic Skeletal Muscle

PubMed Central

Muir, Lindsey A.; Murry, Charles E.

2016-01-01

In Duchenne muscular dystrophy (DMD) and other muscle wasting disorders, cell therapies are a promising route for promoting muscle regeneration by supplying a functional copy of the missing dystrophin gene and contributing new muscle fibers. The clinical application of cell-based therapies is resource intensive, and it will therefore be necessary to address key limitations that reduce cell engraftment into muscle tissue. A pressing issue is poor donor cell survival following transplantation, which in preclinical studies limits the ability to effectively test the impact of cell-based therapy on whole muscle function. We, therefore, sought to improve engraftment and the functional impact of in vivo myogenically converted dermal fibroblasts (dFbs) using a prosurvival cocktail (PSC) that includes heat shock followed by treatment with insulin-like growth factor-1, a caspase inhibitor, a Bcl-XL peptide, a KATP channel opener, basic fibroblast growth factor, Matrigel, and cyclosporine A. Advantages of dFbs include compatibility with the autologous setting, ease of isolation, and greater proliferative potential than DMD satellite cells. dFbs expressed tamoxifen-inducible MyoD and carried a mini-dystrophin gene driven by a muscle-specific promoter. After transplantation into muscles of mdx mice, a 70% reduction in donor cells was observed by day 5, and a 94% reduction by day 28. However, treatment with PSC gave a nearly three-fold increase in donor cells in early engraftment, and greatly increased the number of donor-contributed muscle fibers and total engrafted area in transplanted muscles. Furthermore, dystrophic muscles that received dFbs with PSC displayed reduced injury with eccentric contractions and an increase in maximum isometric force. Thus, enhancing survival of myogenic cells increases engraftment and improves structure and function of dystrophic muscle. PMID:27503462

Prosurvival Factors Improve Functional Engraftment of Myogenically Converted Dermal Cells into Dystrophic Skeletal Muscle.

PubMed

Muir, Lindsey A; Murry, Charles E; Chamberlain, Jeffrey S

2016-09-07

In Duchenne muscular dystrophy (DMD) and other muscle wasting disorders, cell therapies are a promising route for promoting muscle regeneration by supplying a functional copy of the missing dystrophin gene and contributing new muscle fibers. The clinical application of cell-based therapies is resource intensive, and it will therefore be necessary to address key limitations that reduce cell engraftment into muscle tissue. A pressing issue is poor donor cell survival following transplantation, which in preclinical studies limits the ability to effectively test the impact of cell-based therapy on whole muscle function. We, therefore, sought to improve engraftment and the functional impact of in vivo myogenically converted dermal fibroblasts (dFbs) using a prosurvival cocktail (PSC) that includes heat shock followed by treatment with insulin-like growth factor-1, a caspase inhibitor, a Bcl-XL peptide, a K ATP channel opener, basic fibroblast growth factor, Matrigel, and cyclosporine A. Advantages of dFbs include compatibility with the autologous setting, ease of isolation, and greater proliferative potential than DMD satellite cells. dFbs expressed tamoxifen-inducible MyoD and carried a mini-dystrophin gene driven by a muscle-specific promoter. After transplantation into muscles of mdx mice, a 70% reduction in donor cells was observed by day 5, and a 94% reduction by day 28. However, treatment with PSC gave a nearly three-fold increase in donor cells in early engraftment, and greatly increased the number of donor-contributed muscle fibers and total engrafted area in transplanted muscles. Furthermore, dystrophic muscles that received dFbs with PSC displayed reduced injury with eccentric contractions and an increase in maximum isometric force. Thus, enhancing survival of myogenic cells increases engraftment and improves structure and function of dystrophic muscle.

Isolation and expansion of human pluripotent stem cell-derived hepatic progenitor cells by growth factor defined serum-free culture conditions.

PubMed

Fukuda, Takayuki; Takayama, Kazuo; Hirata, Mitsuhi; Liu, Yu-Jung; Yanagihara, Kana; Suga, Mika; Mizuguchi, Hiroyuki; Furue, Miho K

2017-03-15

Limited growth potential, narrow ranges of sources, and difference in variability and functions from batch to batch of primary hepatocytes cause a problem for predicting drug-induced hepatotoxicity during drug development. Human pluripotent stem cell (hPSC)-derived hepatocyte-like cells in vitro are expected as a tool for predicting drug-induced hepatotoxicity. Several studies have already reported efficient methods for differentiating hPSCs into hepatocyte-like cells, however its differentiation process is time-consuming, labor-intensive, cost-intensive, and unstable. In order to solve this problem, expansion culture for hPSC-derived hepatic progenitor cells, including hepatic stem cells and hepatoblasts which can self-renewal and differentiate into hepatocytes should be valuable as a source of hepatocytes. However, the mechanisms of the expansion of hPSC-derived hepatic progenitor cells are not yet fully understood. In this study, to isolate hPSC-derived hepatic progenitor cells, we tried to develop serum-free growth factor defined culture conditions using defined components. Our culture conditions were able to isolate and grow hPSC-derived hepatic progenitor cells which could differentiate into hepatocyte-like cells through hepatoblast-like cells. We have confirmed that the hepatocyte-like cells prepared by our methods were able to increase gene expression of cytochrome P450 enzymes upon encountering rifampicin, phenobarbital, or omeprazole. The isolation and expansion of hPSC-derived hepatic progenitor cells in defined culture conditions should have advantages in terms of detecting accurate effects of exogenous factors on hepatic lineage differentiation, understanding mechanisms underlying self-renewal ability of hepatic progenitor cells, and stably supplying functional hepatic cells. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Self-production of tissue factor-coagulation factor VII complex by ovarian cancer cells.

PubMed

Yokota, N; Koizume, S; Miyagi, E; Hirahara, F; Nakamura, Y; Kikuchi, K; Ruf, W; Sakuma, Y; Tsuchiya, E; Miyagi, Y

2009-12-15

Thromboembolic events are a major complication in ovarian cancer patients. Tissue factor (TF) is frequently overexpressed in ovarian cancer tissue and correlates with intravascular thrombosis. TF binds to coagulation factor VII (fVII), changing it to its active form, fVIIa. This leads to activation of the extrinsic coagulation cascade. fVII is produced by the liver and believed to be supplied from blood plasma at the site of coagulation. However, we recently showed that ovarian cancer cells express fVII transcripts under normoxia and that this transcription is inducible under hypoxia. These findings led us to hypothesise that ovarian cancer cells are intrinsically associated with TF-fVIIa coagulation activity, which could result in thrombosis. In this study, we examined whether ectopically expressed fVII could cause thrombosis by means of immunohistochemistry, RT-PCR, western blotting and flow cytometry. Ectopic fVII expression occurs frequently in ovarian cancers, particularly in clear cell carcinoma. We further showed that ovarian cancer cells express TF-fVIIa on the cell surface under normoxia and that this procoagulant activity is enhanced by hypoxic stimuli. Moreover, we showed that ovarian cancer cells secrete microparticles (MPs) with TF-fVIIa activity. Production of this procoagulant secretion is enhanced under hypoxia. These results raise the possibility that cancer cell-derived TF-fVIIa could cause thrombotic events in ovarian cancer patients.

In vivo demonstration of cell types in bone that harbor epidermal growth factor receptors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martineau-Doize, B.; Lai, W.H.; Warshawsky, H.

1988-08-01

The binding and internalization of (/sup 125/I)iodoepidermal growth factor (EGF) by bone cells of the rat was demonstrated in situ by quantitative radioautography. Specific binding sites were observed on a cell profile enriched in endocytic components, including lysosome-like structures, a rough endoplasmic reticulum-rich cell profile, and a cell profile that histologically resembles an undifferentiated precursor cell. By the criteria of gel filtration and precipitability by trichloroacetic acid, most of the bound (/sup 125/I)iodo-EGF was considered intact. By morphological criteria none of the cell profiles that bound (/sup 125/I)iodo-EGF corresponded to fully formed osteoclasts or osteoblasts. The endocytic cell was foundmore » in the epiphyseal plate between the invading capillary and the transverse and longitudinal cartilage septa as well as near osteoclasts in the zone of mixed spicules. The rough endoplasmic reticulum-rich cell was present in vacated chondrocyte lacunae of the epiphyseal plate close to the metaphysis, and the poorly differentiated cell was observed between the mixed spicules of the metaphysis. Similar cell types were also found in the alveolar bone surrounding the incisors. These cells may be the origin of established bone cell lines that harbor high concentrations of EGF receptors and may also be responsible for the humoral hypercalcemia in response to the reported actions of injected EGF or transforming growth factor-alpha as well as that of malignancy.« less

PD-L1 expression on immune cells is a favorable prognostic factor for vulvar squamous cell carcinoma patients.

PubMed

Sznurkowski, Jacek J; Żawrocki, Anton; Sznurkowska, Katarzyna; Pęksa, Rafał; Biernat, Wojciech

2017-10-27

Anti-immune programmed death-ligand 1 (PD-L1) pathway is used by the tumor to overcome immune system and serves as immunotherapy target in various malignancies. To investigate the expression of PD-L1 in vulvar squamous cell carcinoma (vSCC) and to assess it's clinicopathological and prognostic significance. Immunohistochemical PD-L1 expression was evaluated in 84 vSCCs with previously defined status of p16 and DNA-HPV, infiltration of immune cells: CD8+, CD4+, FOXP3+, CD56+, CD68+, and GZB+ cells. PD-L1 positivity was defined as ≥5% of PD-L1-positive cells. Survival analyses included the Kaplan-Meier method, log-rank test and Cox proportional hazards model. PD-L1 expression was detected on cancer and peritumoral immune cells. PD-L1-positivity of cancer nests (27/84, 32.1%) was correlated with higher infiltration of CD4+ (p=0.037), CD8+ (p=0.02), FOXP3+ (p=0.007), CD68+ (p=0.021) cells, while PD-L1 positivity of peritumoral immune cells (51/84, 60.7%) was correlated with higher infiltration of intraepithelial FOXP3+ cells only (p=0.037).PD-L1-positivity of cancer cells but not immune cells, was more frequently observed in p16-negative tumors (p=0.004). High-risk HPV-status did not correlate with the PD-L1 status of cancer and immune cells (p=1.000) and (p=1.000) respectively). Median follow up was 89.20 months (range 1.7-189.5). PD-L1 positivity of peritumoral immune cells was found to be an independent favorable prognostic factor for OS. Conclusion: This study highlights the importance of comprehensive PD-L1 assessment in both cancer and immune cells. PD-L1 expression on peritumoral immune cells seems to be an additional prognostic factor in vSCC patients and may influence the results by anti-PD-L1 treatment.

PD-L1 expression on immune cells is a favorable prognostic factor for vulvar squamous cell carcinoma patients

PubMed Central

Sznurkowski, Jacek J.; Żawrocki, Anton; Sznurkowska, Katarzyna; Pęksa, Rafał; Biernat, Wojciech

2017-01-01

Background Anti-immune programmed death-ligand 1 (PD-L1) pathway is used by the tumor to overcome immune system and serves as immunotherapy target in various malignancies. Aim To investigate the expression of PD-L1 in vulvar squamous cell carcinoma (vSCC) and to assess it's clinicopathological and prognostic significance. Methods Immunohistochemical PD-L1 expression was evaluated in 84 vSCCs with previously defined status of p16 and DNA-HPV, infiltration of immune cells: CD8+, CD4+, FOXP3+, CD56+, CD68+, and GZB+ cells. PD-L1 positivity was defined as ≥5% of PD-L1-positive cells. Survival analyses included the Kaplan–Meier method, log-rank test and Cox proportional hazards model. Results PD-L1 expression was detected on cancer and peritumoral immune cells. PD-L1-positivity of cancer nests (27/84, 32.1%) was correlated with higher infiltration of CD4+ (p=0.037), CD8+ (p=0.02), FOXP3+ (p=0.007), CD68+ (p=0.021) cells, while PD-L1 positivity of peritumoral immune cells (51/84, 60.7%) was correlated with higher infiltration of intraepithelial FOXP3+ cells only (p=0.037). PD-L1-positivity of cancer cells but not immune cells, was more frequently observed in p16-negative tumors (p=0.004). High-risk HPV-status did not correlate with the PD-L1 status of cancer and immune cells (p=1.000) and (p=1.000) respectively). Median follow up was 89.20 months (range 1.7-189.5). PD-L1 positivity of peritumoral immune cells was found to be an independent favorable prognostic factor for OS. Conclusion: This study highlights the importance of comprehensive PD-L1 assessment in both cancer and immune cells. PD-L1 expression on peritumoral immune cells seems to be an additional prognostic factor in vSCC patients and may influence the results by anti-PD-L1 treatment. PMID:29163797

Robust Programming Problems Based on the Mean-Variance Model Including Uncertainty Factors

NASA Astrophysics Data System (ADS)

Hasuike, Takashi; Ishii, Hiroaki

2009-01-01

This paper considers robust programming problems based on the mean-variance model including uncertainty sets and fuzzy factors. Since these problems are not well-defined problems due to fuzzy factors, it is hard to solve them directly. Therefore, introducing chance constraints, fuzzy goals and possibility measures, the proposed models are transformed into the deterministic equivalent problems. Furthermore, in order to solve these equivalent problems efficiently, the solution method is constructed introducing the mean-absolute deviation and doing the equivalent transformations.

Identification of Regulatory Factors for Mesenchymal Stem Cell-Derived Salivary Epithelial Cells in a Co-Culture System

PubMed Central

Park, Yun-Jong; Koh, Jin; Gauna, Adrienne E.; Chen, Sixue; Cha, Seunghee

2014-01-01

Patients with Sjögren’s syndrome or head and neck cancer patients who have undergone radiation therapy suffer from severe dry mouth (xerostomia) due to salivary exocrine cell death. Regeneration of the salivary glands requires a better understanding of regulatory mechanisms by which stem cells differentiate into exocrine cells. In our study, bone marrow-derived mesenchymal stem cells were co-cultured with primary salivary epithelial cells from C57BL/6 mice. Co-cultured bone marrow-derived mesenchymal stem cells clearly resembled salivary epithelial cells, as confirmed by strong expression of salivary gland epithelial cell-specific markers, such as alpha-amylase, muscarinic type 3 receptor, aquaporin-5, and cytokeratin 19. To identify regulatory factors involved in this differentiation, transdifferentiated mesenchymal stem cells were analyzed temporarily by two-dimensional-gel-electrophoresis, which detected 58 protein spots (>1.5 fold change, p<0.05) that were further categorized into 12 temporal expression patterns. Of those proteins only induced in differentiated mesenchymal stem cells, ankryin-repeat-domain-containing-protein 56, high-mobility-group-protein 20B, and transcription factor E2a were selected as putative regulatory factors for mesenchymal stem cell transdifferentiation based on putative roles in salivary gland development. Induction of these molecules was confirmed by RT-PCR and western blotting on separate sets of co-cultured mesenchymal stem cells. In conclusion, our study is the first to identify differentially expressed proteins that are implicated in mesenchymal stem cell differentiation into salivary gland epithelial cells. Further investigation to elucidate regulatory roles of these three transcription factors in mesenchymal stem cell reprogramming will provide a critical foundation for a novel cell-based regenerative therapy for patients with xerostomia. PMID:25402494

Factors affecting reconstitution of the T cell compartment in allogeneic haematopoietic cell transplant recipients.

PubMed

Fallen, P R; McGreavey, L; Madrigal, J A; Potter, M; Ethell, M; Prentice, H G; Guimarães, A; Travers, P J

2003-11-01

The factors affecting T cell reconstitution post haematopoietic cell transplantation (HCT) are not well characterised. We carried out a longitudinal analysis of T cell reconstitution in 32 HCT recipients during the first 12 months post transplant. We analysed reconstitution of naïve, memory and effector T cells, their diversity and monitored thymic output using TCR rearrangement excision circles (TRECs). Thymic-independent pathways were responsible for the rapid reconstitution of memory and effector T cells less than 6 months post HCT. Thymic-dependent pathways were activated between 6 and 12 months in the majority of patients with naïve T cell numbers increasing in parallel with TREC levels. Increasing patient age, chronic GVHD and T cell depletion (with or without pretransplant Campath-1H) predicted low TREC levels and slow naïve T cell recovery. Furthermore, increasing patient age also predicted high memory and effector T cell numbers. The effects of post HCT immunosuppression, total body irradiation, donor leucocyte infusions, T cell dose and post HCT infections on T cell recovery were also analysed. However, no effects of these single variables across a variety of different age, GVHD and T cell depletion groups were apparent. This study suggests that future analysis of the factors affecting T cell reconstitution and studies aimed at reactivating the thymus through therapeutic intervention should be analysed in age-, GVHD- and TCD-matched patient groups.

Cell phones and brain tumors: a review including the long-term epidemiologic data.

PubMed

Khurana, Vini G; Teo, Charles; Kundi, Michael; Hardell, Lennart; Carlberg, Michael

2009-09-01

The debate regarding the health effects of low-intensity electromagnetic radiation from sources such as power lines, base stations, and cell phones has recently been reignited. In the present review, the authors attempt to address the following question: is there epidemiologic evidence for an association between long-term cell phone usage and the risk of developing a brain tumor? Included with this meta-analysis of the long-term epidemiologic data are a brief overview of cell phone technology and discussion of laboratory data, biological mechanisms, and brain tumor incidence. In order to be included in the present meta-analysis, studies were required to have met all of the following criteria: (i) publication in a peer-reviewed journal; (ii) inclusion of participants using cell phones for > or = 10 years (ie, minimum 10-year "latency"); and (iii) incorporation of a "laterality" analysis of long-term users (ie, analysis of the side of the brain tumor relative to the side of the head preferred for cell phone usage). This is a meta-analysis incorporating all 11 long-term epidemiologic studies in this field. The results indicate that using a cell phone for > or = 10 years approximately doubles the risk of being diagnosed with a brain tumor on the same ("ipsilateral") side of the head as that preferred for cell phone use. The data achieve statistical significance for glioma and acoustic neuroma but not for meningioma. The authors conclude that there is adequate epidemiologic evidence to suggest a link between prolonged cell phone usage and the development of an ipsilateral brain tumor.

Paracrine Engineering of Human Explant-Derived Cardiac Stem Cells to Over-Express Stromal-Cell Derived Factor 1α Enhances Myocardial Repair.

PubMed

Tilokee, Everad L; Latham, Nicholas; Jackson, Robyn; Mayfield, Audrey E; Ye, Bin; Mount, Seth; Lam, Buu-Khanh; Suuronen, Erik J; Ruel, Marc; Stewart, Duncan J; Davis, Darryl R

2016-07-01

First generation cardiac stem cell products provide indirect cardiac repair but variably produce key cardioprotective cytokines, such as stromal-cell derived factor 1α, which opens the prospect of maximizing up-front paracrine-mediated repair. The mesenchymal subpopulation within explant derived human cardiac stem cells underwent lentiviral mediated gene transfer of stromal-cell derived factor 1α. Unlike previous unsuccessful attempts to increase efficacy by boosting the paracrine signature of cardiac stem cells, cytokine profiling revealed that stromal-cell derived factor 1α over-expression prevented lv-mediated "loss of cytokines" through autocrine stimulation of CXCR4+ cardiac stem cells. Stromal-cell derived factor 1α enhanced angiogenesis and stem cell recruitment while priming cardiac stem cells to readily adopt a cardiac identity. As compared to injection with unmodified cardiac stem cells, transplant of stromal-cell derived factor 1α enhanced cells into immunodeficient mice improved myocardial function and angiogenesis while reducing scarring. Increases in myocardial stromal-cell derived factor 1α content paralleled reductions in myocyte apoptosis but did not influence long-term engraftment or the fate of transplanted cells. Transplantation of stromal-cell derived factor 1α transduced cardiac stem cells increased the generation of new myocytes, recruitment of bone marrow cells, new myocyte/vessel formation and the salvage of reversibly damaged myocardium to enhance cardiac repair after experimental infarction. Stem Cells 2016;34:1826-1835. © 2016 AlphaMed Press.

Phosphoproteome and transcription factor activity profiling identify actions of the anti-inflammatory agent UTL-5g in LPS stimulated RAW 264.7 cells including disrupting actin remodeling and STAT-3 activation.

PubMed

Carruthers, Nicholas J; Stemmer, Paul M; Chen, Ben; Valeriote, Frederick; Gao, Xiaohua; Guatam, Subhash C; Shaw, Jiajiu

2017-09-15

UTL-5g is a novel small-molecule TNF-alpha modulator. It reduces cisplatin-induced side effects by protecting kidney, liver, and platelets, thereby increasing tolerance for cisplatin. UTL-5g also reduces radiation-induced acute liver toxicity. The mechanism of action for UTL-5g is not clear at the present time. A phosphoproteomic analysis to a depth of 4943 phosphopeptides and a luminescence-based transcription factor activity assay were used to provide complementary analyses of signaling events that were disrupted by UTL-5g in RAW 264.7 cells. Transcriptional activity downstream of the interferon gamma, IL-6, type 1 Interferon, TGF-β, PKC/Ca 2+ and the glucocorticoid receptor pathways were disrupted by UTL-5g. Phosphoproteomic analysis indicated that hyperphosphorylation of proteins involved in actin remodeling was suppressed by UTL-5g (gene set analysis, FDR < 1%) as was phosphorylation of Stat3, consistent with the IL-6 results in the transcription factor assay. Neither analysis indicated that LPS-induced activation of the NF-kB, cAMP/PKA and JNK signaling pathways were affected by UTL-5g. This global characterization of UTL-5g activity in a macrophage cell line discovered that it disrupts selected aspects of LPS signaling including Stat3 activation and actin remodeling providing new insight on how UTL-5g acts to reduce cisplatin-induced side effects. Copyright © 2017 Elsevier B.V. All rights reserved.

Priming Dental Pulp Stem Cells With Fibroblast Growth Factor-2 Increases Angiogenesis of Implanted Tissue-Engineered Constructs Through Hepatocyte Growth Factor and Vascular Endothelial Growth Factor Secretion.

PubMed

Gorin, Caroline; Rochefort, Gael Y; Bascetin, Rumeyza; Ying, Hanru; Lesieur, Julie; Sadoine, Jérémy; Beckouche, Nathan; Berndt, Sarah; Novais, Anita; Lesage, Matthieu; Hosten, Benoit; Vercellino, Laetitia; Merlet, Pascal; Le-Denmat, Dominique; Marchiol, Carmen; Letourneur, Didier; Nicoletti, Antonino; Vital, Sibylle Opsahl; Poliard, Anne; Salmon, Benjamin; Muller, Laurent; Chaussain, Catherine; Germain, Stéphane

2016-03-01

Tissue engineering strategies based on implanting cellularized biomaterials are promising therapeutic approaches for the reconstruction of large tissue defects. A major hurdle for the reliable establishment of such therapeutic approaches is the lack of rapid blood perfusion of the tissue construct to provide oxygen and nutrients. Numerous sources of mesenchymal stem cells (MSCs) displaying angiogenic potential have been characterized in the past years, including the adult dental pulp. Establishment of efficient strategies for improving angiogenesis in tissue constructs is nevertheless still an important challenge. Hypoxia was proposed as a priming treatment owing to its capacity to enhance the angiogenic potential of stem cells through vascular endothelial growth factor (VEGF) release. The present study aimed to characterize additional key factors regulating the angiogenic capacity of such MSCs, namely, dental pulp stem cells derived from deciduous teeth (SHED). We identified fibroblast growth factor-2 (FGF-2) as a potent inducer of the release of VEGF and hepatocyte growth factor (HGF) by SHED. We found that FGF-2 limited hypoxia-induced downregulation of HGF release. Using three-dimensional culture models of angiogenesis, we demonstrated that VEGF and HGF were both responsible for the high angiogenic potential of SHED through direct targeting of endothelial cells. In addition, FGF-2 treatment increased the fraction of Stro-1+/CD146+ progenitor cells. We then applied in vitro FGF-2 priming to SHED before encapsulation in hydrogels and in vivo subcutaneous implantation. Our results showed that FGF-2 priming is more efficient than hypoxia at increasing SHED-induced vascularization compared with nonprimed controls. Altogether, these data demonstrate that FGF-2 priming enhances the angiogenic potential of SHED through the secretion of both HGF and VEGF. ©AlphaMed Press.

Prognostic factors for head and neck cancer of unknown primary including the impact of human papilloma virus infection.

PubMed

Axelsson, Lars; Nyman, Jan; Haugen-Cange, Hedda; Bove, Mogens; Johansson, Leif; De Lara, Shahin; Kovács, Anikó; Hammerlid, Eva

2017-06-10

Head and neck cancer of unknown primary (HNCUP) is rare and prospective studies are lacking. The impact of different prognostic factors such as age and N stage is not completely known, the optimal treatment is not yet established, and the reported survival rates vary. In the last decade, human papilloma virus (HPV) has been identified as a common cause of and important prognostic factor in oropharyngeal cancer, and there is now growing interest in the importance of HPV for HNCUP. The aim of the present study on curatively treated HNCUP was to investigate the prognostic importance of different factors, including HPV status, treatment, and overall survival. A search for HNCUP was performed in the Swedish Cancer Registry, Western health district, between the years 1992-2009. The medical records were reviewed, and only patients with squamous cell carcinoma or undifferentiated carcinoma treated with curative intent were included. The tumor specimens were retrospectively analyzed for HPV with p16 immunostaining. Sixty-eight patients were included. The mean age was 59 years. The majority were males, and had N2 tumors. Sixty-nine percent of the tumors were HPV positive using p16 staining. Patients who were older than 70 years, patients with N3-stage tumors, and patients with tumors that were p16 negative had a significantly worse prognosis. The overall 5-year survival rate for patients with p16-positive tumors was 88% vs 61% for p16-negative tumors. Treatment with neck dissection and postoperative radiation or (chemo) radiation had 81 and 88% 5-year survival rates, respectively. The overall and disease-free 5-year survival rates for all patients in the study were 82 and 74%. Curatively treated HNCUP had good survival. HPV infection was common. Independent prognostic factors for survival were age over 70 years, HPV status and N3 stage. We recommend that HPV analysis should be performed routinely for HNCUP. Treatment with neck dissection and postoperative radiation or

The C. elegans SoxC protein SEM-2 opposes differentiation factors to promote a proliferative blast cell fate in the postembryonic mesoderm

PubMed Central

Tian, Chenxi; Shi, Herong; Colledge, Clark; Stern, Michael; Waterston, Robert; Liu, Jun

2011-01-01

The proper development of multicellular organisms requires precise regulation and coordination of cell fate specification, cell proliferation and differentiation. Abnormal regulation and coordination of these processes could lead to disease, including cancer. We have examined the function of the sole C. elegans SoxC protein, SEM-2, in the M lineage, which produces the postembryonic mesoderm. We found that SEM-2/SoxC is both necessary and sufficient to promote a proliferating blast cell fate, the sex myoblast fate, over a differentiated striated bodywall muscle fate. A number of factors control the specific expression of sem-2 in the sex myoblast precursors and their descendants. This includes direct control of sem-2 expression by a Hox-PBC complex. The crucial nature of the HOX/PBC factors in directly enhancing expression of this proliferative factor in the C. elegans M lineage suggests a possible more general link between Hox-PBC factors and SoxC proteins in regulating cell proliferation. PMID:21307099

Effects of Pseudomonas aeruginosa virulence factor pyocyanin on human urothelial cell function and viability.

PubMed

McDermott, Catherine; Chess-Williams, Russ; Grant, Gary D; Perkins, Anthony V; McFarland, Amelia J; Davey, Andrew K; Anoopkumar-Dukie, Shailendra

2012-03-01

We determined the effects of Pseudomonas aeruginosa virulence factor pyocyanin on human urothelial cell viability and function in vitro. RT4 urothelial cells were treated with pyocyanin (1 to 100 μM) for 24 hours. After exposure the treatment effects were measured according to certain end points, including changes in urothelial cell viability, reactive oxygen species formation, caspase-3 activity, basal and stimulated adenosine triphosphate release, SA-β-gal activity and detection of acidic vesicular organelles. The 24-hour pyocyanin treatment resulted in a concentration dependent decrease in cell viability at concentrations of 25 μM or greater, and increases in reactive oxygen species formation and caspase-3 activity at 25 μM or greater. Basal adenosine triphosphate release was significantly decreased at all tested pyocyanin concentrations while stimulated adenosine triphosphate release was significantly inhibited at pyocyanin concentrations of 12.5 μM or greater with no significant stimulated release at 100 μM. Pyocyanin treated RT4 cells showed morphological characteristics associated with cellular senescence, including SA-β-gal expression. This effect was not evident at 100 μM pyocyanin and may have been due to apoptotic cell death, as indicated by increased caspase-3 activity. An increase in acridine orange stained vesicular-like organelles was observed in RT4 urothelial cells after pyocyanin treatment. Exposure to pyocyanin alters urothelial cell viability, reactive oxygen species production and caspase-3 activity. Treatment also results in cellular senescence, which may affect the ability of urothelium to repair during infection. The virulence factor depressed stimulated adenosine triphosphate release, which to our knowledge is a novel finding with implications for awareness of bladder filling in patients with P. aeruginosa urinary tract infection. Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier

Determining the Involvement and Therapeutic Implications of Host Cellular Factors in Hepatitis C Virus Cell-to-Cell Spread

PubMed Central

Barretto, Naina; Sainz, Bruno; Hussain, Snawar

2014-01-01

ABSTRACT Hepatitis C virus (HCV) infects 180 million people worldwide and is a leading cause of liver diseases such as fibrosis, cirrhosis, and hepatocellular carcinoma. It has been shown that HCV can spread to naive cells using two distinct entry mechanisms, “cell-free” entry of infectious extracellular virions that have been released by infected cells and direct “cell-to-cell” transmission. Here, we examined host cell requirements for HCV spread and found that the cholesterol uptake receptor NPC1L1, which we recently identified as being an antiviral target involved in HCV cell-free entry/spread, is also required for the cell-to-cell spread. In contrast, the very low density lipoprotein (VLDL) pathway, which is required for the secretion of cell-free infectious virus and thus has been identified as an antiviral target for blocking cell-free virus secretion/spread, is not required for cell-to-cell spread. Noting that HCV cell-free and cell-to-cell spread share some common factors but not others, we tested the therapeutic implications of these observations and demonstrate that inhibitors that target cell factors required for both forms of HCV spread exhibit synergy when used in combination with interferon (a representative inhibitor of intracellular HCV production), while inhibitors that block only cell-free spread do not. This provides insight into the mechanistic basis of synergy between interferon and HCV entry inhibitors and highlights the broader, previously unappreciated impact blocking HCV cell-to-cell spread can have on the efficacy of HCV combination therapies. IMPORTANCE HCV can spread to naive cells using distinct mechanisms: “cell-free” entry of extracellular virus and direct “cell-to-cell” transmission. Herein, we identify the host cell HCV entry factor NPC1L1 as also being required for HCV cell-to-cell spread, while showing that the VLDL pathway, which is required for the secretion of cell-free infectious virus, is not required for cell-to-cell

A stem cell medium containing neural stimulating factor induces a pancreatic cancer stem-like cell-enriched population

PubMed Central

WATANABE, YUSAKU; YOSHIMURA, KIYOSHI; YOSHIKAWA, KOICHI; TSUNEDOMI, RYOICHI; SHINDO, YOSHITARO; MATSUKUMA, SOU; MAEDA, NORIKO; KANEKIYO, SHINSUKE; SUZUKI, NOBUAKI; KURAMASU, ATSUO; SONODA, KOUHEI; TAMADA, KOJI; KOBAYASHI, SEI; SAYA, HIDEYUKI; HAZAMA, SHOICHI; OKA, MASAAKI

2014-01-01

Cancer stem cells (CSCs) have been studied for their self-renewal capacity and pluripotency, as well as their resistance to anticancer therapy and their ability to metastasize to distant organs. CSCs are difficult to study because their population is quite low in tumor specimens. To overcome this problem, we established a culture method to induce a pancreatic cancer stem-like cell (P-CSLC)-enriched population from human pancreatic cancer cell lines. Human pancreatic cancer cell lines established at our department were cultured in CSC-inducing media containing epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), leukemia inhibitory factor (LIF), neural cell survivor factor-1 (NSF-1), and N-acetylcysteine. Sphere cells were obtained and then transferred to a laminin-coated dish and cultured for approximately two months. The surface markers, gene expression, aldehyde dehydrogenase (ALDH) activity, cell cycle, and tumorigenicity of these induced cells were examined for their stem cell-like characteristics. The population of these induced cells expanded within a few months. The ratio of CD24high, CD44high, epithelial specific antigen (ESA) high, and CD44variant (CD44v) high cells in the induced cells was greatly enriched. The induced cells stayed in the G0/G1 phase and demonstrated mesenchymal and stemness properties. The induced cells had high tumorigenic potential. Thus, we established a culture method to induce a P-CSLCenriched population from human pancreatic cancer cell lines. The CSLC population was enriched approximately 100-fold with this method. Our culture method may contribute to the precise analysis of CSCs and thus support the establishment of CSC-targeting therapy. PMID:25118635

Environmental Factors Contribute to β Cell Endoplasmic Reticulum Stress and Neo-Antigen Formation in Type 1 Diabetes

PubMed Central

Marré, Meghan L.; Piganelli, Jon D.

2017-01-01

Type 1 diabetes (T1D) is an autoimmune disease in which immune-mediated targeting and destruction of insulin-producing pancreatic islet β cells leads to chronic hyperglycemia. There are many β cell proteins that are targeted by autoreactive T cells in their native state. However, recent studies have demonstrated that many β cell proteins are recognized as neo-antigens following posttranslational modification (PTM). Although modified neo-antigens are well-established targets of pathology in other autoimmune diseases, the effects of neo-antigens in T1D progression and the mechanisms by which they are generated are not well understood. We have demonstrated that PTM occurs during endoplasmic reticulum (ER) stress, a process to which β cells are uniquely susceptible due to the high rate of insulin production in response to dynamic glucose sensing. In the context of genetic susceptibility to autoimmunity, presentation of these modified neo-antigens may activate autoreactive T cells and cause pathology. However, inherent β cell ER stress and protein PTM do not cause T1D in every genetically susceptible individual, suggesting the contribution of additional factors. Indeed, many environmental factors, such as viral infection, chemicals, or inflammatory cytokines, are associated with T1D onset, but the mechanisms by which these factors lead to disease onset remain unknown. Since these environmental factors also cause ER stress, exposure to these factors may enhance production of neo-antigens, therefore boosting β cell recognition by autoreactive T cells and exacerbating T1D pathogenesis. Therefore, the combined effects of physiological ER stress and the stress that is induced by environmental factors may lead to breaks in peripheral tolerance, contribute to antigen spread, and hasten disease onset. This Hypothesis and Theory article summarizes what is currently known about ER stress and protein PTM in autoimmune diseases including T1D and proposes a role for

Depletion of mitochondrial fission factor DRP1 causes increased apoptosis in human colon cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Inoue-Yamauchi, Akane, E-mail: ainoyama@research.twmu.ac.jp; Oda, Hideaki

2012-04-27

Highlights: Black-Right-Pointing-Pointer DRP1 is required for mitochondrial fission in colon cancer cells. Black-Right-Pointing-Pointer DRP1 participates in inhibition of colon cancer cell apoptosis. Black-Right-Pointing-Pointer DRP1 can inhibit apoptosis through the regulation of cytochrome c release. -- Abstract: Mitochondria play a critical role in regulation of apoptosis, a form of programmed cell death, by releasing apoptogenic factors including cytochrome c. Growing evidence suggests that dynamic changes in mitochondrial morphology are involved in cellular apoptotic response. However, whether DRP1-mediated mitochondrial fission is required for induction of apoptosis remains speculative. Here, we show that siRNA-mediated DRP1 knockdown promoted accumulation of elongated mitochondria in HCT116more » and SW480 human colon cancer cells. Surprisingly, DRP1 down-regulation led to decreased proliferation and increased apoptosis of these cells. A higher rate of cytochrome c release and reductions in mitochondrial membrane potential were also revealed in DRP1-depleted cells. Taken together, our present findings suggest that mitochondrial fission factor DRP1 inhibits colon cancer cell apoptosis through the regulation of cytochrome c release and mitochondrial membrane integrity.« less

Evaluation of the secretion and release of vascular endothelial growth factor from two-dimensional culture and three-dimensional cell spheroids formed with stem cells and osteoprecursor cells.

PubMed

Lee, Hyunjin; Lee, Sung-Il; Ko, Youngkyung; Park, Jun-Beom

2018-05-18

Co-culture has been applied in cell therapy, including stem cells, and has been reported to give enhanced functionality. In this study, stem-cell spheroids were formed in concave micromolds at different ratios of stem cells to osteoprecursor cells, and the amount of secretion of vascular endothelial growth factor (VEGF) was evaluated. Gingiva-derived stem cells and osteoprecursor cells in the amount of 6 × 105 were seeded on a 24-well culture plate or concave micromolds. The ratios of stem cells to osteoprecursor cells included: 0:4 (group 1), 1:3 (group 2), 2:2 (group 3), 3:1 (group 4), and 4:0 (group 5). The morphology of cells in a 2-dimensional culture (groups 1-5) showed a fibroblast-like appearance. The secretion of VEGF increased with the increase in stem cells, and a statistically significant increase was noted in groups 3, 4 and 5 when compared with the media-only group (p < 0.05). Osteoprecursor cells formed spheroids in concave microwells, and no noticeable change in the morphology was noted with the increase in stem cells. Spheroids containing stem cells were positive for the stem-cell markers SSEA-4. The secretion of VEGF from cell spheroids increased with the increase in stem cells. This study showed that cell spheroids formed with stem cells and osteoprecursor cells with different ratios, using microwells, had paracrine effects on the stem cells. The secretion of VEGF increased with the increase in stem cells. This stem-cell spheroid may be applied for tissue-engineering purposes.

Using low-risk factors to generate non-integrated human induced pluripotent stem cells from urine-derived cells.

PubMed

Wang, Linli; Chen, Yuehua; Guan, Chunyan; Zhao, Zhiju; Li, Qiang; Yang, Jianguo; Mo, Jian; Wang, Bin; Wu, Wei; Yang, Xiaohui; Song, Libing; Li, Jun

2017-11-02

Because the lack of an induced pluripotent stem cell (iPSC) induction system with optimal safety and efficiency limits the application of these cells, development of such a system is important. To create such an induction system, we screened a variety of reprogrammed plasmid combinations and multiple compounds and then verified the system's feasibility using urine cells from different individuals. We also compared large-scale iPSC chromosomal variations and expression of genes associated with genomic stability between this system and the traditional episomal system using karyotype and quantitative reverse transcription polymerase chain reaction analyses. We developed a high-efficiency episomal system, the 6F/BM1-4C system, lacking tumorigenic factors for human urine-derived cell (hUC) reprogramming. This system includes six low-risk factors (6F), Oct4, Glis1, Klf4, Sox2, L-Myc, and the miR-302 cluster. Transfected hUCs were treated with four compounds (4C), inhibitor of lysine-demethylase1, methyl ethyl ketone, glycogen synthase kinase 3 beta, and histone deacetylase, within a short time period. Comparative analysis revealed significantly decreased chromosomal variation in iPSCs and significantly increased Sirt1 expression compared with iPSCs induced using the traditional episomal system. The 6F/BM1-4C system effectively induces reprogramming of urine cells in samples obtained from different individuals. iPSCs induced using the 6F/BM1-4C system are more stable at the cytogenetic level and have potential value for clinical application.

Targeting miR-381-NEFL axis sensitizes glioblastoma cells to temozolomide by regulating stemness factors and multidrug resistance factors.

PubMed

Wang, Zeyou; Yang, Jing; Xu, Gang; Wang, Wei; Liu, Changhong; Yang, Honghui; Yu, Zhibin; Lei, Qianqian; Xiao, Lan; Xiong, Jing; Zeng, Liang; Xiang, Juanjuan; Ma, Jian; Li, Guiyuan; Wu, Minghua

2015-02-20

MicroRNA-381 (miR-381) is a highly expressed onco-miRNA that is involved in malignant progression and has been suggested to be a good target for glioblastoma multiforme (GBM) therapy. In this study, we employed two-dimensional fluorescence differential gel electrophoresis (2-D DIGE) and MALDI-TOF/TOF-MS/MS to identify 27 differentially expressed proteins, including the significantly upregulated neurofilament light polypeptide (NEFL), in glioblastoma cells in which miR-381 expression was inhibited. We identified NEFL as a novel target molecule of miR-381 and a tumor suppressor gene. In human astrocytoma clinical specimens, NEFL was downregulated with increased levels of miR-381 expression. Either suppressing miR-381 or enforcing NEFL expression dramatically sensitized glioblastoma cells to temozolomide (TMZ), a promising chemotherapeutic agent for treating GBMs. The mechanism by which these cells were sensitized to TMZ was investigated by inhibiting various multidrug resistance factors (ABCG2, ABCC3, and ABCC5) and stemness factors (ALDH1, CD44, CKIT, KLF4, Nanog, Nestin, and SOX2). Our results further demonstrated that miR-381 overexpression reversed the viability of U251 cells exhibiting NEFL-mediated TMZ sensitivity. In addition, NEFL-siRNA also reversed the proliferation rate of U251 cells exhibiting locked nucleic acid (LNA)-anti-miR-381-mediated TMZ sensitivity. Overall, the miR-381-NEFL axis is important for TMZ resistance in GBM and may potentially serve as a novel therapeutic target for glioma.

The grape berry-specific basic helix-loop-helix transcription factor VvCEB1 affects cell size.

PubMed

Nicolas, Philippe; Lecourieux, David; Gomès, Eric; Delrot, Serge; Lecourieux, Fatma

2013-02-01

The development of fleshy fruits involves complex physiological and biochemical changes. After fertilization, fruit growth usually begins with cell division, continues with both cell division and expansion, allowing fruit set to occur, and ends with cell expansion only. In spite of the economical importance of grapevine, the molecular mechanisms controlling berry growth are not fully understood. The present work identified and characterized Vitis vinifera cell elongation bHLH protein (VvCEB1), a basic helix-loop-helix (bHLH) transcription factor controlling cell expansion in grape. VvCEB1 was expressed specifically in berry-expanding tissues with a maximum around veraison. The study of VvCEB1 promoter activity in tomato confirmed its specific fruit expression during the expansion phase. Overexpression of VvCEB1 in grape embryos showed that this protein stimulates cell expansion and affects the expression of genes involved in cell expansion, including genes of auxin metabolism and signalling. Taken together, these data show that VvCEB1 is a fruit-specific bHLH transcription factor involved in grape berry development.

The grape berry-specific basic helix–loop–helix transcription factor VvCEB1 affects cell size

PubMed Central

Lecourieux, Fatma

2013-01-01

The development of fleshy fruits involves complex physiological and biochemical changes. After fertilization, fruit growth usually begins with cell division, continues with both cell division and expansion, allowing fruit set to occur, and ends with cell expansion only. In spite of the economical importance of grapevine, the molecular mechanisms controlling berry growth are not fully understood. The present work identified and characterized Vitis vinifera cell elongation bHLH protein (VvCEB1), a basic helix–loop–helix (bHLH) transcription factor controlling cell expansion in grape. VvCEB1 was expressed specifically in berry-expanding tissues with a maximum around veraison. The study of VvCEB1 promoter activity in tomato confirmed its specific fruit expression during the expansion phase. Overexpression of VvCEB1 in grape embryos showed that this protein stimulates cell expansion and affects the expression of genes involved in cell expansion, including genes of auxin metabolism and signalling. Taken together, these data show that VvCEB1 is a fruit-specific bHLH transcription factor involved in grape berry development. PMID:23314819

Experimental and theoretical investigations of the quality factor for n+p silicon solar cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Garlick, G.F.J.; Kachare, A.H.

1980-01-01

Many N/sup +/P silicon cells made with silicon from different growth techniques have current-voltage relations of the form: I.I/sub 0/ (exp(qV/AkT) - 1) where the quality factor A is non-integral, is >1 and shows a temperature dependence. The dark forward characteristics of such cells have been measured over a range of temperature and the behavior of the factor A derived from them. A new model is presented on the assumption of non-uniform distributions of recombination levels in the junction depletion layer. This model shows good agreement with experimental data. The cells investigated had evaporated top metallization and so the junctionmore » contamination giving the recombination levels is likely to be a result of junction diffusion and is not specific to the metallization processing. The model needs further development and evaluation in order to apply it to the illuminated cell behavior and also to include any effects of distributed sheet resistance in the N/sup +/ layer. 17 refs.« less

Risk factors in past histories and familial episodes related to development of testicular germ cell tumor.

PubMed

Kanto, Satoru; Hiramatsu, Masayoshi; Suzuki, Kenichi; Ishidoya, Shigeto; Saito, Hideo; Yamada, Shigeyuki; Satoh, Makoto; Saito, Seiichi; Fukuzaki, Atsushi; Arai, Yoichi

2004-08-01

A retrospective study was conducted to examine the host factors of 240 testicular germ cell tumor patients. This study was performed to address a new theory proposed by Skakkebaek called testicular dysgenesis syndrome which claims that cryptorchism, hypospadias, poor semen quality and testicular germ cell tumors are symptoms of an underlying testicular dysgenesis in uterus. The past health histories and familial episodes of 240 testicular germ cell tumor patients were examined. The past health histories included cryptorchism, hypospadias, infertility, atrophic testis and inguinal hernia. Of the 240 patients, 13 (5.4%) had a history of cryptorchism or orchidopexy. Two (0.8%) showed existence of hypospadias or had experienced urethroplasty. Among 129 married couples, 104 (80.6%) couples were fertile. Three (1.3%) patients developed testicular tumors after they were diagnosed as infertile or came to the hospital with the complaints of infertility. Four (1.7%) had contralateral atrophic testis. 19 (7.9%) had experienced inguinal herniorrhaphy before age 15. Three (1.3%) had testicular germ cell tumor patients among their family or relatives. The testicular germ cell tumor patients showed a considerable incidence of complications such as cryptorchism, hypospadias and incomplete closure of processus vaginalis. Cryptorchism, perinatal factors and familial factors could be risks for developing testicular germ cell tumors.

Nerve Growth Factor-Induced Angiogenesis: 1. Endothelial Cell Tube Formation Assay.

PubMed

Lazarovici, Philip; Lahiani, Adi; Gincberg, Galit; Haham, Dikla; Fluksman, Arnon; Benny, Ofra; Marcinkiewicz, Cezary; Lelkes, Peter I

2018-01-01

Nerve growth factor (NGF) is a neurotrophin promoting survival, proliferation, differentiation, and neuroprotection in the embryonal and adult nervous system. NGF also induces angiogenic effects in the cardiovascular system, which may be beneficial in engineering new blood vessels and for developing novel anti-angiogenesis therapies for cancer. Angiogenesis is a cellular process characterized by a number of events, including endothelial cell migration, invasion, and assembly into capillaries. In vitro endothelial tube formation assays are performed using primary human umbilical vein endothelial cells, human aortic endothelial cells, and other human or rodent primary endothelial cells isolated from the vasculature of both tumors and normal tissues. Immortalized endothelial cell lines are also used for these assays. When seeded onto Matrigel, these cells reorganize to create tubelike structure, which may be used as models for studying some aspects of in vitro angiogenesis. Image acquisition by light and fluorescence microscopy and/or quantification of fluorescently labeled cells can be carried out manually or digitally, using commercial software and automated image processing. Here we detail materials, procedure, assay conditions, and cell labeling for quantification of endothelial cell tube formation. This model can be applied to study cellular and molecular mechanisms by which NGF or other neurotrophins promote angiogenesis. This model may also be useful for the development of potential angiogenic and/or anti-angiogenic drugs targeting NGF receptors.

Liver-derived systemic factors drive β-cell hyperplasia in insulin resistant states

DOE Office of Scientific and Technical Information (OSTI.GOV)

El Ouaamari, Abdelfattah; Kawamori, Dan; Dirice, Ercument

2013-02-21

Integrative organ cross-talk regulates key aspects of energy homeostasis and its dysregulation may underlie metabolic disorders such as obesity and diabetes. To test the hypothesis that cross-talk between the liver and pancreatic islets modulates β-cell growth in response to insulin resistance, we used the Liver-specific Insulin Receptor Knockout (LIRKO) mouse, a unique model that exhibits dramatic islet hyperplasia. Using complementary in vivo parabiosis and transplantation assays, and in vitro islet culture approaches, we demonstrate that humoral, non-neural, non-cell autonomous factor(s) induce β-cell proliferation in LIRKO mice. Furthermore, we report that a hepatocyte-derived factor(s) stimulates mouse and human β-cell proliferation inmore » ex vivo assays, independent of ambient glucose and insulin levels. These data implicate the liver as a critical source of β-cell growth factors in insulin resistant states.« less

Distinctions Among Circulating Antibody Secreting Cell Populations, Including B-1 Cells, in Human Adult Peripheral Blood1

PubMed Central

Quách, Tâm D.; Rodríguez-Zhurbenko, Nely; Hopkins, Thomas J.; Guo, Xiaoti; Vázquez, Ana María Hernández; Li, Wentian; Rothstein, Thomas L.

2015-01-01

Human antibody secreting cell (ASC) populations in circulation are not well studied. In addition to B-1 (CD20+CD27+CD38lo/intCD43+) cell and the conventional plasmablast (CD20-CD27hiCD38hi) cell populations, here we identified a novel B cell population termed 20+38hi B cells (CD20+CD27hiCD38hi) that spontaneously secretes antibody. At steady state, 20+38hi B cells are distinct from plasmablasts on the basis of CD20 expression, amount of antibody production, frequency of mutation, and diversity of B cell receptor repertoire. However, cytokine treatment of 20+38hi B cells induces loss of CD20 and acquisition of CD138, suggesting that 20+38hi B cells are precursors to plasmablasts, or pre-plasmablasts. We then evaluated similarities and differences between CD20+CD27+CD38lo/intCD43+ B-1 cells, CD20+CD27hiCD38hi 20+38hi B cells, CD20-CD27hiCD38hi plasmablasts, and CD20+CD27+CD38lo/intCD43- memory B cells. We found that B-1 cells differ from 20+38hi B cells and plasmablasts in numbers of ways, including antigen expression, morphological appearance, transcriptional profiling, antibody skewing, antibody repertoire, and secretory response to stimulation. In terms of gene expression, B-1 cells align more closely with memory B cells than with 20+38hi B cells or plasmablasts, but differ in that memory B cells do not express antibody secretion related genes. We found that, B-1 cell antibodies utilize Vh4-34, which is often associated with autoreactivity, 3 to 6-fold more often than other B cell populations. Along with selective production of IgM anti-PC, this data suggests that human B-1 cells might be preferentially selected for autoreactivity/natural-specificity. In sum, our results indicate that human healthy adult peripheral blood at steady state consists of 3 distinct ASC populations. PMID:26740107

Fibroblast growth factor regulates insulin-like growth factor-binding protein production by vascular smooth muscle cells.

PubMed

Ververis, J; Ku, L; Delafontaine, P

1994-02-01

Insulin-like growth factor I is an important mitogen for vascular smooth muscle cells, and its effects are regulated by several binding proteins. Western ligand blotting of conditioned medium from rat aortic smooth muscle cells detected a 24 kDa binding protein and a 28 kDa glycosylated variant of this protein, consistent with insulin-like growth factor binding protein-4 by size. Low amounts of a glycosylated 38 to 42 kDa doublet (consistent with binding protein-3) and a 31 kDa non-glycosylated protein also were present. Basic fibroblast growth factor markedly increased secretion of the 24 kDa binding protein and its 28 kDa glycosylated variant. This effect was dose- and time-dependent and was inhibited by co-incubation with cycloheximide. Crosslinking of [125I]-insulin-like growth factor I to cell monolayers revealed no surface-associated binding proteins, either basally or after agonist treatment. Induction of binding protein production by fibroblast growth factor at sites of vascular injury may be important in vascular proliferative responses in vivo.

A Synopsis of Factors Regulating Beta Cell Development and Beta Cell Mass

PubMed Central

Prasadan, Krishna; Shiota, Chiyo; Xiangwei, Xiao; Ricks, David; Fusco, Joseph; Gittes, George

2016-01-01

The insulin-secreting beta cells in the endocrine pancreas regulate blood glucose levels, and loss of functional beta cells leads to insulin deficiency, hyperglycemia (high blood glucose) and diabetes mellitus. Current treatment strategies for type-1 (autoimmune) diabetes are islet transplantation, which has significant risks and limitations, or normalization of blood glucose with insulin injections, which is clearly not ideal. The type-1 patients can lack insulin counter-regulatory mechanism; therefore, hypoglycemia is a potential risk. Hence, a cell-based therapy offers a better alternative for the treatment of diabetes. Past research was focused on attempting to generate replacement beta cells from stem cells, however, recently there has been an increasing interest in identifying mechanisms that will lead to the conversion of pre-existing differentiated endocrine cells into beta cells. The goal of this review is to provide an overview of several of the key factors that regulate new beta cell formation (neogenesis) and beta cell proliferation. PMID:27105622

Oligodendrocyte Precursor Cells Synthesize Neuromodulatory Factors

PubMed Central

Sakry, Dominik; Yigit, Hatice; Dimou, Leda; Trotter, Jacqueline

2015-01-01

NG2 protein-expressing oligodendrocyte progenitor cells (OPC) are a persisting and major glial cell population in the adult mammalian brain. Direct synaptic innervation of OPC by neurons throughout the brain together with their ability to sense neuronal network activity raises the question of additional physiological roles of OPC, supplementary to generating myelinating oligodendrocytes. In this study we investigated whether OPC express neuromodulatory factors, typically synthesized by other CNS cell types. Our results show that OPC express two well-characterized neuromodulatory proteins: Prostaglandin D2 synthase (PTGDS) and neuronal Pentraxin 2 (Nptx2/Narp). Expression levels of the enzyme PTGDS are influenced in cultured OPC by the NG2 intracellular region which can be released by cleavage and localizes to glial nuclei upon transfection. Furthermore PTGDS mRNA levels are reduced in OPC from NG2-KO mouse brain compared to WT cells after isolation by cell sorting and direct analysis. These results show that OPC can contribute to the expression of these proteins within the CNS and suggest PTGDS expression as a downstream target of NG2 signaling. PMID:25966014

Transforming growth factor β-mediated suppression of antitumor T cells requires FoxP1 transcription factor expression.

PubMed

Stephen, Tom L; Rutkowski, Melanie R; Allegrezza, Michael J; Perales-Puchalt, Alfredo; Tesone, Amelia J; Svoronos, Nikolaos; Nguyen, Jenny M; Sarmin, Fahmida; Borowsky, Mark E; Tchou, Julia; Conejo-Garcia, Jose R

2014-09-18

Tumor-reactive T cells become unresponsive in advanced tumors. Here we have characterized a common mechanism of T cell unresponsiveness in cancer driven by the upregulation of the transcription factor Forkhead box protein P1 (Foxp1), which prevents CD8⁺ T cells from proliferating and upregulating Granzyme-B and interferon-γ in response to tumor antigens. Accordingly, Foxp1-deficient lymphocytes induced rejection of incurable tumors and promoted protection against tumor rechallenge. Mechanistically, Foxp1 interacted with the transcription factors Smad2 and Smad3 in preactivated CD8⁺ T cells in response to microenvironmental transforming growth factor-β (TGF-β), and was essential for its suppressive activity. Therefore, Smad2 and Smad3-mediated c-Myc repression requires Foxp1 expression in T cells. Furthermore, Foxp1 directly mediated TGF-β-induced c-Jun transcriptional repression, which abrogated T cell activity. Our results unveil a fundamental mechanism of T cell unresponsiveness different from anergy or exhaustion, driven by TGF-β signaling on tumor-associated lymphocytes undergoing Foxp1-dependent transcriptional regulation. Copyright © 2014 Elsevier Inc. All rights reserved.

Predictive factors for long-term engraftment of autologous blood stem cells.

PubMed

Duggan, P R; Guo, D; Luider, J; Auer, I; Klassen, J; Chaudhry, A; Morris, D; Glück, S; Brown, C B; Russell, J A; Stewart, D A

2000-12-01

Data from 170 consecutive patients aged 19-66 years (median age 46 years) who underwent unmanipulated autologous blood stem cell transplant (ASCT) were analyzed to determine if total CD34+ cells/kg infused, CD34+ subsets (CD34+41+, CD34+90+, CD34+33-, CD34+38-, CD34+38-DR-), peripheral blood CD34+ cell (PBCD34+) count on first apheresis day, or various clinical factors were associated with low blood counts 6 months post ASCT. Thirty-four patients were excluded from analysis either because of death (n = 17) or re-induction chemotherapy prior to 6 months post ASCT (n = 13), or because of lack of follow-up data (n = 4). Of the remaining 136 patients, 46% had low WBC ( < 4 x 10(9)/l), 41% low platelets (<150 x 10(9)/l), and 34% low hemoglobin ( < 120 g/l) at a median of 6 months following ASCT. By Spearman's rank correlation, both the total CD34+ cell dose/kg and the PBCD34+ count correlated with 6 month blood counts better than any subset of CD34+ cells or any clinical factor. The PBCD34+ count was overall a stronger predictor of 6 month blood counts than was the total CD34+ cells/kg infused. Both factors retained their significance in multivariate analysis, controlling for clinical factors. In conclusion, subsets of CD34+ cells and clinical factors are inferior to the total CD34+ cell dose/kg and PBCD34+ count in predicting 6 month blood counts following ASCT.

A critical role for transcription factor Smad4 in T cell function independent of transforming growth factor beta receptor signaling

PubMed Central

Gu, Ai-Di; Zhang, Song; Wang, Yunqi; Xiong, Hui; Curtis, Thomas A.; Wan, Yisong Y.

2014-01-01

Summary Transforming growth factor-beta (TGF-β) suppresses T cell function to maintain self-tolerance and to promote tumor immune evasion. Yet how Smad4, a transcription factor component of TGF-β signaling, regulates T cell function remains unclear. Here we have demonstrated an essential role for Smad4 in promoting T cell function during autoimmunity and anti-tumor immunity. Smad4 deletion rescued the lethal autoimmunity resulting from transforming growth factor-beta receptor (TGF-βR) deletion and compromised T-cell-mediated tumor rejection. While Smad4 was dispensable for T cell generation, homeostasis and effector function, it was essential for T cell proliferation following activation in vitro and in vivo. The transcription factor Myc was identified to mediate Smad4-controlled T cell proliferation. This study thus reveals a requirement of Smad4 for T-cell-mediated autoimmunity and tumor rejection, which is beyond the current paradigm. It highlights a TGF-βR-independent role for Smad4 in promoting T cell function, autoimmunity and anti-tumor immunity. PMID:25577439

Glial cell line-derived neurotrophic factor in combination with insulin-like growth factor 1 and basic fibroblast growth factor promote in vitro culture of goat spermatogonial stem cells.

PubMed

Bahadorani, M; Hosseini, S M; Abedi, P; Abbasi, H; Nasr-Esfahani, M H

2015-01-01

Growth factors are increasingly considered as important regulators of spermatogonial stem cells (SSCs). This study investigated the effects of various growth factors (GDNF, IGF1, bFGF, EGF and GFRalpha-1) on purification and colonization of undifferentiated goat SSCs under in vitro and in vivo conditions. Irrespective of the culture condition used, the first signs of developing colonies were observed from day 4 of culture onwards. The number of colonies developed in GDNF + IGF1 + bFGF culture condition was significantly higher than the other groups (p < 0.05). In contrast, the size of colonies developed in GDNF + EGF + LIF culture condition was significantly higher than the other groups (p < 0.05). Immunocytochemical stationing for specific biomarkers of somatic cells (vimentin, alpha-inhibin and α-SMA) and spermatogonial cells (PLZF, THY 1, VASA, alpha-1 integrin, bet-1 integrin and DBA) revealed that both cell types existed in developing colonies, irrespective of the culture condition used. Even though, the relative abundance of VASA, FGFR3, OCT4, PLZF, BCL6B and THY1 transcription factors in GDNF + IGF1 + bFGF treatment group was significantly higher than the other groups (p < 0.05). Additionally, goat SSCs developed in the latter culture condition could colonize within the seminiferous tubules of the germ-cell depleted recipient mice following xenotransplantation. Obtained results demonstrated that combination of GDNF with IGF1 and bFGF promote in vitro culture of goat SSCs while precludes uncontrolled proliferation of somatic cells.

Mast Cell Proteases 6 and 7 Stimulate Angiogenesis by Inducing Endothelial Cells to Release Angiogenic Factors

PubMed Central

de Souza, Devandir Antonio; Borges, Antonio Carlos; Santana, Ana Carolina; Oliver, Constance; Jamur, Maria Célia

2015-01-01

Mast cell proteases are thought to be involved with tumor progression and neo-vascularization. However, their exact role is still unclear. The present study was undertaken to further elucidate the function of specific subtypes of recombinant mouse mast cell proteases (rmMCP-6 and 7) in neo-vascularization. SVEC4-10 cells were cultured on Geltrex® with either rmMCP-6 or 7 and tube formation was analyzed by fluorescence microscopy and scanning electron microscopy. Additionally, the capacity of these proteases to induce the release of angiogenic factors and pro and anti-angiogenic proteins was analyzed. Both rmMCP-6 and 7 were able to stimulate tube formation. Scanning electron microscopy showed that incubation with the proteases induced SVEC4-10 cells to invade the gel matrix. However, the expression and activity of metalloproteases were not altered by incubation with the mast cell proteases. Furthermore, rmMCP-6 and rmMCP-7 were able to induce the differential release of angiogenic factors from the SVEC4-10 cells. rmMCP-7 was more efficient in stimulating tube formation and release of angiogenic factors than rmMCP-6. These results suggest that the subtypes of proteases released by mast cells may influence endothelial cells during in vivo neo-vascularization. PMID:26633538

Minoxidil Promotes Hair Growth through Stimulation of Growth Factor Release from Adipose-Derived Stem Cells

PubMed Central

Choi, Nahyun; Shin, Soyoung; Song, Sun U.; Sung, Jong-Hyuk

2018-01-01

Minoxidil directly promotes hair growth via the stimulation of dermal papilla (DP) and epithelial cells. Alternatively, there is little evidence for indirect promotion of hair growth via stimulation of adipose-derived stem cells (ASCs). We investigated whether minoxidil stimulates ASCs and if increased growth factor secretion by ASCs facilitates minoxidil-induced hair growth. Telogen-to-anagen induction was examined in mice. Cultured DP cells and vibrissae hair follicle organ cultures were used to further examine the underlying mechanisms. Subcutaneous injection of minoxidil-treated ASCs accelerated telogen-to-anagen transition in mice, and increased hair weight at day 14 post-injection. Minoxidil did not alter ASC proliferation, but increased migration and tube formation. Minoxidil also increased the secretion of growth factors from ASCs, including chemokine (C-X-C motif) ligand 1 (CXCL1), platelet-derived endothelial cell growth factor (PD-ECGF), and platelet-derived growth factor-C (PDGF-C). Minoxidil increased extracellular signal–regulated kinases 1/2 (ERK1/2) phosphorylation, and concomitant upregulation of PD-ECGF and PDGF-C mRNA levels were attenuated by an ERK inhibitor. Subcutaneous injection of CXCL1, PD-ECGF, or PDGF-C enhanced anagen induction in mice, and both CXCL1 and PDGF-C increased hair length in ex vivo organ culture. Treatment with CXCL1, PD-ECGF, or PDGF-C also increased the proliferation index in DP cells. Finally, topical application of CXCL1, PD-ECGF, or PDGF-C with 2% minoxidil enhanced anagen induction when compared to minoxidil alone. Minoxidil stimulates ASC motility and increases paracrine growth factor signaling. Minoxidil-stimulated secretion of growth factors by ASCs may enhance hair growth by promoting DP proliferation. Therefore, minoxidil can be used as an ASC preconditioning agent for hair regeneration. PMID:29495622

Minoxidil Promotes Hair Growth through Stimulation of Growth Factor Release from Adipose-Derived Stem Cells.

PubMed

Choi, Nahyun; Shin, Soyoung; Song, Sun U; Sung, Jong-Hyuk

2018-02-28

Minoxidil directly promotes hair growth via the stimulation of dermal papilla (DP) and epithelial cells. Alternatively, there is little evidence for indirect promotion of hair growth via stimulation of adipose-derived stem cells (ASCs). We investigated whether minoxidil stimulates ASCs and if increased growth factor secretion by ASCs facilitates minoxidil-induced hair growth. Telogen-to-anagen induction was examined in mice. Cultured DP cells and vibrissae hair follicle organ cultures were used to further examine the underlying mechanisms. Subcutaneous injection of minoxidil-treated ASCs accelerated telogen-to-anagen transition in mice, and increased hair weight at day 14 post-injection. Minoxidil did not alter ASC proliferation, but increased migration and tube formation. Minoxidil also increased the secretion of growth factors from ASCs, including chemokine (C-X-C motif) ligand 1 (CXCL1), platelet-derived endothelial cell growth factor (PD-ECGF), and platelet-derived growth factor-C (PDGF-C). Minoxidil increased extracellular signal-regulated kinases 1/2 (ERK1/2) phosphorylation, and concomitant upregulation of PD-ECGF and PDGF-C mRNA levels were attenuated by an ERK inhibitor. Subcutaneous injection of CXCL1, PD-ECGF, or PDGF-C enhanced anagen induction in mice, and both CXCL1 and PDGF-C increased hair length in ex vivo organ culture. Treatment with CXCL1, PD-ECGF, or PDGF-C also increased the proliferation index in DP cells. Finally, topical application of CXCL1, PD-ECGF, or PDGF-C with 2% minoxidil enhanced anagen induction when compared to minoxidil alone. Minoxidil stimulates ASC motility and increases paracrine growth factor signaling. Minoxidil-stimulated secretion of growth factors by ASCs may enhance hair growth by promoting DP proliferation. Therefore, minoxidil can be used as an ASC preconditioning agent for hair regeneration.

Universal cell frame for high-pressure water electrolyzer and electrolyzer including the same

DOEpatents

Schmitt, Edwin W.; Norman, Timothy J.

2013-01-08

Universal cell frame generic for use as an anode frame and as a cathode frame in a water electrolyzer. According to one embodiment, the universal cell frame includes a unitary annular member having a central opening. Four trios of transverse openings are provided in the annular member, each trio being spaced apart by about 90 degrees. A plurality of internal radial passageways fluidly interconnect the central opening and each of the transverse openings of two diametrically-opposed trios of openings, the other two trios of openings lacking corresponding radial passageways. Sealing ribs are provided on the top and bottom surfaces of the annular member. The present invention is also directed at a water electrolyzer that includes two such cell frames, one being used as the anode frame and the other being used as the cathode frame, the cathode frame being rotated 90 degrees relative to the anode frame.

Factors that contribute to biomarker responses in humans including a study in individuals taking Vitamin C supplementation.

PubMed

Anderson, D

2001-09-01

It is possible in many situations to identify humans exposed to potentially toxic materials in the workplace and in the environment. As in most human studies, there tends to be a high degree of interindividual variability in response to chemical insults. Some non-exposed control individuals exhibit as high a level of damage as some exposed individuals and some of these have levels of damage as low as many of the controls. Thus, it is only the mean values of the groups that can substantiate an exposure-related problem; the data on an individual basis are still of limited use. While human lymphocytes remain the most popular cell type for monitoring purposes, sperm, buccal, nasal, epithelial and placental cells are also used. However, for interpretation of responses, the issue of confounding factors must be addressed. There are endogenous confounding factors, such as age, gender, and genetic make-up and exogenous ones, including lifestyle habits (smoking, drinking, etc.) There are biomarkers of exposure, effect/response and susceptibility and the last may be influenced by the genotype and polymorphism genes existing in a population. From our own studies, confounding effects on cytogenetic damage and ras oncoproteins will be considered in relation to workers exposed to vinyl chloride and petroleum emissions and to volunteers taking Vitamin C supplementation. Smoking history, exposure and duration of employment affected the worker studies. For petroleum emissions, so did gender and season of exposure. For the non-smoking volunteer Vitamin C supplementation study, cholesterol levels, plasma Vitamin C levels, lipid peroxidation products and DNA damage in the Comet assay were also measured. Gender affected differences in Vitamin C levels, antioxidant capacity and the number of chromosome aberrations induced by bleomycin challenge in vitro. The results were the same for both high and low cholesterol subjects. The relationship between biomarkers and the various factors which

Cancer cell-soluble factors reprogram mesenchymal stromal cells to slow cycling, chemoresistant cells with a more stem-like state.

PubMed

El-Badawy, Ahmed; Ghoneim, Mohamed A; Gabr, Mahmoud M; Salah, Radwa Ayman; Mohamed, Ihab K; Amer, Marwa; El-Badri, Nagwa

2017-11-07

Mesenchymal stem cells (MSCs) play different roles in modulating tumor progression, growth, and metastasis. MSCs are recruited to the tumor site in large numbers and subsequently have an important microenvironmental role in modulating tumor progression and drug sensitivity. However, the effect of the tumor microenvironment on MSC plasticity remains poorly understood. Herein, we report a paracrine effect of cancer cells, in which they secrete soluble factors that promote a more stem-like state in bone marrow mesenchymal stem cells (BM-MSCs). The effect of soluble factors secreted from MCF7, Hela, and HepG2 cancer cell lines on BM-MSCs was assessed using a Transwell indirect coculture system. After 5 days of coculture, BM-MSCs were characterized by flow cytometry for surface marker expression, by qPCR for gene expression profile, and by confocal immunofluorescence for marker expression. We then measured the sensitivity of cocultured BM-MSCs to chemotherapeutic agents, their cell cycle profile, and their response to DNA damage. The sphere formation, invasive properties, and in-vivo performance of BM-MSCs after coculture with cancer cells were also measured. Indirect coculture of cancer cells and BM-MSCs, without direct cell contact, generated slow cycling, chemoresistant spheroid stem cells that highly expressed markers of pluripotency, cancer cells, and cancer stem cells (CSCs). They also displayed properties of a side population and enhanced sphere formation in culture. Accordingly, these cells were termed cancer-induced stem cells (CiSCs). CiSCs showed a more mesenchymal phenotype that was further augmented upon TGF-β stimulation and demonstrated a high expression of the β-catenin pathway and ALDH1A1. These findings demonstrate that MSCs, recruited to the tumor microenvironment in large numbers, may display cellular plasticity, acquire a more stem-like state, and acquire some properties of CSCs upon exposure to cancer cell-secreted factors. These acquired

Dynamic Modulation of Expression of Lentiviral Restriction Factors in Primary CD4+ T Cells following Simian Immunodeficiency Virus Infection.

PubMed

Rahmberg, Andrew R; Rajakumar, Premeela A; Billingsley, James M; Johnson, R Paul

2017-04-01

Although multiple restriction factors have been shown to inhibit HIV/SIV replication, little is known about their expression in vivo Expression of 45 confirmed and putative HIV/SIV restriction factors was analyzed in CD4 + T cells from peripheral blood and the jejunum in rhesus macaques, revealing distinct expression patterns in naive and memory subsets. In both peripheral blood and the jejunum, memory CD4 + T cells expressed higher levels of multiple restriction factors compared to naive cells. However, relative to their expression in peripheral blood CD4 + T cells, jejunal CCR5 + CD4 + T cells exhibited significantly lower expression of multiple restriction factors, including APOBEC3G , MX2 , and TRIM25 , which may contribute to the exquisite susceptibility of these cells to SIV infection. In vitro stimulation with anti-CD3/CD28 antibodies or type I interferon resulted in upregulation of distinct subsets of multiple restriction factors. After infection of rhesus macaques with SIVmac239, the expression of most confirmed and putative restriction factors substantially increased in all CD4 + T cell memory subsets at the peak of acute infection. Jejunal CCR5 + CD4 + T cells exhibited the highest levels of SIV RNA, corresponding to the lower restriction factor expression in this subset relative to peripheral blood prior to infection. These results illustrate the dynamic modulation of confirmed and putative restriction factor expression by memory differentiation, stimulation, tissue microenvironment and SIV infection and suggest that differential expression of restriction factors may play a key role in modulating the susceptibility of different populations of CD4 + T cells to lentiviral infection. IMPORTANCE Restriction factors are genes that have evolved to provide intrinsic defense against viruses. HIV and simian immunodeficiency virus (SIV) target CD4 + T cells. The baseline level of expression in vivo and degree to which expression of restriction factors is

Transforming Growth Factor-β Drives the Transendothelial Migration of Hepatocellular Carcinoma Cells.

PubMed

Koudelkova, Petra; Costina, Victor; Weber, Gerhard; Dooley, Steven; Findeisen, Peter; Winter, Peter; Agarwal, Rahul; Schlangen, Karin; Mikulits, Wolfgang

2017-10-10

The entry of malignant hepatocytes into blood vessels is a key step in the dissemination and metastasis of hepatocellular carcinoma (HCC). The identification of molecular mechanisms involved in the transmigration of malignant hepatocytes through the endothelial barrier is of high relevance for therapeutic intervention and metastasis prevention. In this study, we employed a model of hepatocellular transmigration that mimics vascular invasion using hepatic sinusoidal endothelial cells and malignant hepatocytes evincing a mesenchymal-like, invasive phenotype by transforming growth factor (TGF)-β. Labelling of respective cell populations with various stable isotopes and subsequent mass spectrometry analyses allowed the "real-time" detection of molecular changes in both transmigrating hepatocytes and endothelial cells. Interestingly, the proteome profiling revealed 36 and 559 regulated proteins in hepatocytes and endothelial cells, respectively, indicating significant changes during active transmigration that mostly depends on cell-cell interaction rather than on TGF-β alone. Importantly, matching these in vitro findings with HCC patient data revealed a panel of common molecular alterations including peroxiredoxin-3, epoxide hydrolase, transgelin-2 and collectin 12 that are clinically relevant for the patient's survival. We conclude that hepatocellular plasticity induced by TGF-β is crucially involved in blood vessel invasion of HCC cells.

Hypoxia-inducing factors as master regulators of stemness properties and altered metabolism of cancer- and metastasis-initiating cells

PubMed Central

Mimeault, Murielle; Batra, Surinder K

2013-01-01

Accumulating lines of experimental evidence have revealed that hypoxia-inducible factors, HIF-1α and HIF-2α, are key regulators of the adaptation of cancer- and metastasis-initiating cells and their differentiated progenies to oxygen and nutrient deprivation during cancer progression under normoxic and hypoxic conditions. Particularly, the sustained stimulation of epidermal growth factor receptor (EGFR), insulin-like growth factor-1 receptor (IGF-1R), stem cell factor (SCF) receptor KIT, transforming growth factor-β receptors (TGF-βRs) and Notch and their downstream signalling elements such as phosphatidylinositol 3′-kinase (PI3K)/Akt/molecular target of rapamycin (mTOR) may lead to an enhanced activity of HIFs. Moreover, the up-regulation of HIFs in cancer cells may also occur in the hypoxic intratumoral regions formed within primary and secondary neoplasms as well as in leukaemic cells and metastatic prostate and breast cancer cells homing in the hypoxic endosteal niche of bone marrow. The activated HIFs may induce the expression of numerous gene products such as induced pluripotency-associated transcription factors (Oct-3/4, Nanog and Sox-2), glycolysis- and epithelial-mesenchymal transition (EMT) programme-associated molecules, including CXC chemokine receptor 4 (CXCR4), snail and twist, microRNAs and angiogenic factors such as vascular endothelial growth factor (VEGF). These gene products in turn can play critical roles for high self-renewal ability, survival, altered energy metabolism, invasion and metastases of cancer cells, angiogenic switch and treatment resistance. Consequently, the targeting of HIF signalling network and altered metabolic pathways represents new promising strategies to eradicate the total mass of cancer cells and improve the efficacy of current therapies against aggressive and metastatic cancers and prevent disease relapse. PMID:23301832

Bone morphogenetic protein-4 strongly potentiates growth factor-induced proliferation of mammary epithelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Montesano, Roberto; Sarkoezi, Rita; Schramek, Herbert

2008-09-12

Bone morphogenetic proteins (BMPs) are multifunctional cytokines that elicit pleiotropic effects on biological processes such as cell proliferation, cell differentiation and tissue morphogenesis. With respect to cell proliferation, BMPs can exert either mitogenic or anti-mitogenic activities, depending on the target cells and their context. Here, we report that in low-density cultures of immortalized mammary epithelial cells, BMP-4 did not stimulate cell proliferation by itself. However, when added in combination with suboptimal concentrations of fibroblast growth factor (FGF)-2, FGF-7, FGF-10, epidermal growth factor (EGF) or hepatocyte growth factor (HGF), BMP-4 potently enhanced growth factor-induced cell proliferation. These results reveal a hithertomore » unsuspected interplay between BMP-4 and growth factors in the regulation of mammary epithelial cell proliferation. We suggest that the ability of BMP-4 to potentiate the mitogenic activity of multiple growth factors may contribute to mammary gland ductal morphogenesis as well as to breast cancer progression.« less

Dexamethasone enhances agonist induction of tissue factor in monocytes but not in endothelial cells.

PubMed

Bottles, K D; Morrissey, J H

1993-06-01

Stimulation of monocytic cells by inflammatory agents such as bacterial lipopolysaccharide or tumour necrosis factor-alpha leads to the rapid and transient expression of tissue factor, the major cellular initiator of the extrinsic coagulation cascade in both haemostasis and tissue inflammation. In this study we investigated whether the synthetic anti-inflammatory glucocorticoid, dexamethasone, would inhibit agonist induction of tissue factor expression in both monocytes and endothelial cells. Surprisingly, dexamethasone significantly enhanced the induction of tissue factor expression by peripheral blood mononuclear cells and an established monocytic cell line, THP-1, in response to lipopolysaccharide or tumour necrosis factor-alpha. However, unlike monocytic cells, dexamethasone did not enhance agonist induction of tissue factor in endothelial cells. Synergistic enhancement of tissue factor expression by dexamethasone was also reflected in tissue factor mRNA levels in THP-1 cells, but was not the result of improved TF mRNA stability. Synergism between bacterial lipopolysaccharide and glucocorticoid in the induction of monocyte effector function is extremely unusual and may help to explain the variable outcome of glucocorticoid treatment of septic shock.

Tumor necrosis factor-alpha inhibits differentiation of myogenic cells in human urethral rhabdosphincter.

PubMed

Shinohara, Mayuka; Sumino, Yasuhiro; Sato, Fuminori; Kiyono, Tohru; Hashimoto, Naohiro; Mimata, Hiromitsu

2017-06-01

To examine the inhibitory effects of tumor necrosis factor-α on myogenic differentiation of human urethral rhabdosphincter cells. A rhabdosphincter sample was obtained from a patient who underwent total cystectomy. To expand the lifespan of the primary cultured cells, rhabdosphincter myogenic cells were immortalized with mutated cyclin-dependent kinase 4, cyclin D1 and telomerase. The differential potential of the cells was investigated. The transfected human rhabdosphincter cells were induced for myogenic differentiation with recombinant human tumor necrosis factor-α and/or the tumor necrosis factor-α antagonist etanercept at different concentrations, and activation of signaling pathways was monitored. Human rhabdosphincter cells were selectively cultured for at least 40 passages. Molecular analysis confirmed the expression of myosin heavy chain, which is a specific marker of differentiated muscle cells, significantly increased after differentiation induction. Although tumor necrosis factor-α treatment reduced the myosin heavy chain expression in a concentration-dependent manner, etanercept inhibited this suppression. Tumor necrosis factor-α suppressed phosphorylation of protein kinase B and p38, whereas etanercept pretreatment promoted phosphorylation and myosin heavy chain expression in a concentration-dependent manner. Tumor necrosis factor-α inhibits differentiation of urethral rhabdosphincter cells in part through the p38 mitogen-activated protein kinase and phosphoinositide 3-kinase pathways. Inhibition of tumor necrosis factor-α might be a useful strategy to treat stress urinary incontinence. © 2017 The Japanese Urological Association.

Assessment of Growth Factors Secreted by Human Breastmilk Mesenchymal Stem Cells.

PubMed

Kaingade, Pankaj Mahipatrao; Somasundaram, Indumathi; Nikam, Amar Babaso; Sarang, Shabari Amit; Patel, Jagdish Shantilal

2016-01-01

Human breastmilk is a dynamic, multifaceted biological fluid containing nutrients, bioactive substances, and growth factors. It is effective in supporting growth and development of an infant. As breastmilk has been found to possess mesenchymal stem cells, the importance of the components of breastmilk and their physiological roles is increasing day by day. The present study was intended to identify the secretions of growth factors, mainly vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF), from human breastmilk mesenchymal stem cells under basal conditions of in vitro cell culture using synthetic media and human cord serum. The growth factors were analyzed with the enzyme-linked immunosorbent assay technique. The cultured mesenchymal stem cells of breastmilk without serum revealed significant differences in secretions of the VEGF and HGF growth factors (8.55 ± 2.26402 pg/mL and 230.8 ± 45.9861 pg/mL, respectively) compared with mesenchymal stem cells of breastmilk with serum (21.31 ± 4.69 pg/mL and 2,404.42 ± 481.593 pg/mL, respectively). Results obtained from our study demonstrate that both VEGF and HGF are secreted in vitro by human breastmilk mesenchymal stem cells. The roles of VEGF and HGF in surfactant secretion, pulmonary maturation, and neonatal maturity have been well established. Thus, we emphasize that breastmilk-derived MSCs could be a potent therapeutic source in treating neonatal diseases. Besides, due to its immense potency, the study also emphasizes the importance of breastfeeding, which is promoted by organizations like the World Heatlh Organization and UNICEF.

Effect of soluble factors derived from oral cancer cells on the production of interferon-γ from peripheral blood mononuclear cells following stimulation with OK-432.

PubMed

Ohe, Go; Sasai, Akiko; Uchida, Daisuke; Tamatani, Tetsuya; Nagai, Hirokazu; Miyamoto, Youji

2013-08-01

The streptococcal antitumor agent OK-432 is commonly used as an immunopotentiator for immunotherapy in various types of malignant tumors including oral cancer. It has been demonstrated that OK-432 elicits an antitumor effect by stimulating immunocompetent cells, thereby inducing multiple cytokines including interferon (IFN)-γ, interleukin (IL)-2 and IL-12. Serum concentrations of IFN-γ in patients with oral cancer were examined 24 h after administration of OK-432. Serum concentrations of IFN-γ in patients with advanced cancer were significantly lower than those in patients with early cancer. These results suggested that some soluble factors produced by cancer cells may inhibit IFN-γ production with OK-432. Thus, in the present study, an in vitro simulation model was established for the immune status of patients with oral cancer by adding conditioned medium (CM) derived from oral cancer cell lines into a culture of peripheral blood mononuclear cells (PBMCs) derived from a healthy volunteer. We investigated whether soluble factors derived from oral cancer cells affected IFN-γ production from PBMCs following stimulation with OK-432. PBMCs stimulated with OK-432 produced a large amount of IFN-γ; however, both IFN-γ production and cytotoxic activity from PBMCs induced by OK-432 were inhibited by the addition of CM in a dose-dependent manner. In order to examine these inhibitory effects against IFN-γ production, the contribution of inhibitory cytokines such as IL-4, IL-6, IL-10, transforming growth factor-β and vascular endothelial growth factor was investigated. However, neutralization of these inhibitory cytokines did not recover IFN-γ production inhibited by CM. These results indicated that unknown molecules may inhibit IFN-γ production from PBMCs following stimulation with OK-432.

Endothelial cell-fatty acid binding protein 4 promotes angiogenesis: role of stem cell factor/c-kit pathway

PubMed Central

Elmasri, Harun; Ghelfi, Elisa; Yu, Chen-wei; Traphagen, Samantha; Cernadas, Manuela; Cao, Haiming; Shi, Guo-Ping; Plutzky, Jorge; Sahin, Mustafa; Hotamisligil, Gokhan; Cataltepe, Sule

2013-01-01

Fatty acid binding protein 4 (FABP4) plays an important role in regulation of glucose and lipid homeostasis as well as inflammation through its actions in adipocytes and macrophages. FABP4 is also expressed in a subset of endothelial cells, but its role in this cell type is not known. We found that FABP4-deficient human umbilical vein endothelial cells (HUVECs) demonstrate a markedly increased susceptibility to apoptosis as well as decreased migration and capillary network formation. Aortic rings from FABP4−/− mice demonstrated decreased angiogenic sprouting, which was recovered by reconstitution of FABP4. FABP4 was strongly regulated by mTORC1 and inhibited by Rapamycin. FABP4 modulated activation of several important signaling pathways in HUVECs, including downregulation of P38, eNOS, and stem cell factor (SCF)/c-kit signaling. Of these, the SCF/c-kit pathway was found to have a major role in attenuated angiogenic activity of FABP4-deficient ECs as provision of exogenous SCF resulted in a significant recovery in cell proliferation, survival, morphogenesis, and aortic ring sprouting. These data unravel a novel pro-angiogenic role for endothelial cell-FABP4 and suggest that it could be exploited as a potential target for diseases associated with pathological angiogenesis. PMID:22562362

Bacillus subtilis extracytoplasmic function (ECF) sigma factors and defense of the cell envelope

PubMed Central

Helmann, John D.

2016-01-01

Summary Bacillus subtilis provides a model for investigation of the bacterial cell envelope, the first line of defense against environmental threats. Extracytoplasmic function (ECF) sigma factors activate genes that confer resistance to agents that threaten the integrity of the envelope. Although their individual regulons overlap, σW is most closely associated with membrane-active agents, σX with cationic antimicrobial peptide resistance, and σV with resistance to lysozyme. Here, I highlight the role of the σM regulon, which is strongly induced by conditions that impair peptidoglycan synthesis and includes the core pathways of envelope synthesis and cell division, as well as stress-inducible alternative enzymes. Studies of these cell envelope stress responses provide insights into how bacteria acclimate to the presence of antibiotics. PMID:26901131

Interleukin-6 and vascular endothelial growth factor release by renal cell carcinoma cells impedes lymphocyte-dendritic cell cross-talk.

PubMed

Cabillic, F; Bouet-Toussaint, F; Toutirais, O; Rioux-Leclercq, N; Fergelot, P; de la Pintière, C Thomas; Genetet, N; Patard, J-J; Catros-Quemener, V

2006-12-01

Anti-tumour T cell response requires antigen presentation via efficient immunological synapse between antigen presenting cells, e.g. dendritic cells (DC), and specific T cells in an adapted Th1 cytokine context. Nine renal cell carcinoma (RCC) primary culture cells were used as sources of tumour antigens which were loaded on DC (DC-Tu) for autologous T cell activation assays. Cytotoxic activity of lymphocytes stimulated with DC-Tu was evaluated against autologous tumour cells. Assays were performed with 75 grays irradiated tumour cells (Tu irr) and with hydrogen peroxide +/- heat shock (Tu H(2)O(2) +/- HS) treated cells. DC-Tu irr failed to enhance cytotoxic activity of autologous lymphocytes in seven of 13 assays. In all these defective assays, irradiated tumour cells displayed high interleukin (IL)-6 and vascular endothelial growth factor (VEGF) release. Conversely, when tumour cells released low IL-6 levels (n = 4), DC-Tu irr efficiently enhanced CTL activity. When assays were performed with the same RCC cells treated with H(2)O(2) + HS, DC-Tu stimulation resulted in improved CTL activity. H(2)O(2) + HS treatment induced post-apoptotic cell necrosis of tumour cells, totally abrogated their cytokine release [IL-6, VEGF, transforming growth factor (TGF)-beta1] and induced HSP70 expression. Taken together, data show that reduction in IL-6 and VEGF release in the environment of the tumour concomitantly to tumour cell HSP expression favours induction of a stronger anti-tumour CTL response.

Generating autologous hematopoietic cells from human-induced pluripotent stem cells through ectopic expression of transcription factors.

PubMed

Hwang, Yongsung; Broxmeyer, Hal E; Lee, Man Ryul

2017-07-01

Hematopoietic cell transplantation (HCT) is a successful treatment modality for patients with malignant and nonmalignant disorders, usually when no other treatment option is available. The cells supporting long-term reconstitution after HCT are the hematopoietic stem cells (HSCs), which can be limited in numbers. Moreover, finding an appropriate human leukocyte antigen-matched donor can be problematic. If HSCs can be stably produced in large numbers from autologous or allogeneic cell sources, it would benefit HCT. Induced pluripotent stem cells (iPSCs) established from patients' own somatic cells can be differentiated into hematopoietic cells in vitro. This review will highlight recent methods for regulating human (h) iPSC production of HSCs and more mature blood cells. Advancements in transcription factor-mediated regulation of the developmental stages of in-vivo hematopoietic lineage commitment have begun to provide an understanding of the molecular mechanism of hematopoiesis. Such studies involve not only directed differentiation in which transcription factors, specifically expressed in hematopoietic lineage-specific cells, are overexpressed in iPSCs, but also direct conversion in which transcription factors are introduced into patient-derived somatic cells which are dedifferentiated to hematopoietic cells. As iPSCs derived from patients suffering from genetically mutated diseases would express the same mutated genetic information, CRISPR-Cas9 gene editing has been utilized to differentiate genetically corrected iPSCs into normal hematopoietic cells. IPSCs provide a model for molecular understanding of disease, and also may function as a cell population for therapy. Efficient differentiation of patient-specific iPSCs into HSCs and progenitor cells is a potential means to overcome limitations of such cells for HCT, as well as for providing in-vitro drug screening templates as tissue-on-a-chip models.

Growth factor expression pattern of homologous feeder layer for culturing buffalo embryonic stem cell-like cells.

PubMed

Sharma, Ruchi; George, Aman; Kamble, Nitin M; Chauhan, Manmohan S; Singla, Suresh; Manik, Radhey S; Palta, Prabhat

2012-01-01

The present study examined the expression profile of buffalo fetal fibroblasts (BFF) used as a feeder layer for embryonic stem (ES) cell-like cells. The expression of important growth factors was detected in cells at different passages. Mitomycin-C inactivation increased relative expression levels of ACTIVIN-A, TGF-β1, BMP-4 and GREMLIN but not of fibroblast growth factor-2 (FGF-2). The expression level of ACTIVIN-A, transforming growth factor-β1 (TGF-β1), bone morphogenetic protein-4 (BMP-4) and FGF-2 was similar in buffalo fetal fibroblast (BFF) cultured in stem cell medium (SCM), SCM+1000IU mL(-1) leukemia inhibitory factor (LIF), SCM+5 ngmL(-1) FGF-2 or SCM+LIF+FGF-2 for 24 h whereas GREMLIN expression was higher in FGF-2-supplemented groups. In spent medium, the concentration of ACTIVIN-A was higher in FGF-2-supplemented groups whereas that of TGF-β1 was similar in SCM and LIF+FGF-2, which was higher than when either LIF or FGF-2 was used alone. Following culture of ES cell-like cells on a feeder layer for 24 h, the TGF-β1 concentration was higher with LIF+FGF-2 than with LIF or FGF-2 alone which, in turn, was higher than that in SCM. In the LIF+FGF-2 group, the concentration of TGF-β1 was lower and that of ACTIVIN-A was higher in spent medium at 24 h than at 48 h of culture. These results suggest that BFF produce signalling molecules that may help in self-renewal of buffalo ES cell-like cells.

NANOS2 acts downstream of glial cell line-derived neurotrophic factor signaling to suppress differentiation of spermatogonial stem cells.

PubMed

Sada, Aiko; Hasegawa, Kazuteru; Pin, Pui Han; Saga, Yumiko

2012-02-01

Stem cells are maintained by both stem cell-extrinsic niche signals and stem cell-intrinsic factors. During murine spermatogenesis, glial cell line-derived neurotrophic factor (GDNF) signal emanated from Sertoli cells and germ cell-intrinsic factor NANOS2 represent key regulators for the maintenance of spermatogonial stem cells. However, it remains unclear how these factors intersect in stem cells to control their cellular state. Here, we show that GDNF signaling is essential to maintain NANOS2 expression, and overexpression of Nanos2 can alleviate the stem cell loss phenotype caused by the depletion of Gfra1, a receptor for GDNF. By using an inducible Cre-loxP system, we show that NANOS2 expression is downregulated upon the conditional knockout (cKO) of Gfra1, while ectopic expression of Nanos2 in GFRA1-negative spermatogonia does not induce de novo GFRA1 expression. Furthermore, overexpression of Nanos2 in the Gfra1-cKO testes prevents precocious differentiation of the Gfra1-knockout stem cells and partially rescues the stem cell loss phenotypes of Gfra1-deficient mice, indicating that the stem cell differentiation can be suppressed by NANOS2 even in the absence of GDNF signaling. Taken together, we suggest that NANOS2 acts downstream of GDNF signaling to maintain undifferentiated state of spermatogonial stem cells. Copyright © 2011 AlphaMed Press.

Proteomic analysis of cell cycle progression in asynchronous cultures, including mitotic subphases, using PRIMMUS

PubMed Central

Whigham, Arlene; Clarke, Rosemary; Brenes-Murillo, Alejandro J; Estes, Brett; Madhessian, Diana; Lundberg, Emma; Wadsworth, Patricia

2017-01-01

The temporal regulation of protein abundance and post-translational modifications is a key feature of cell division. Recently, we analysed gene expression and protein abundance changes during interphase under minimally perturbed conditions (Ly et al., 2014, 2015). Here, we show that by using specific intracellular immunolabelling protocols, FACS separation of interphase and mitotic cells, including mitotic subphases, can be combined with proteomic analysis by mass spectrometry. Using this PRIMMUS (PRoteomic analysis of Intracellular iMMUnolabelled cell Subsets) approach, we now compare protein abundance and phosphorylation changes in interphase and mitotic fractions from asynchronously growing human cells. We identify a set of 115 phosphorylation sites increased during G2, termed ‘early risers’. This set includes phosphorylation of S738 on TPX2, which we show is important for TPX2 function and mitotic progression. Further, we use PRIMMUS to provide the first a proteome-wide analysis of protein abundance remodeling between prophase, prometaphase and anaphase. PMID:29052541

Apoptosis of mouse hippocampal cells induced by Taenia crassiceps metacestode factor.

PubMed

Zepeda, N; Solano, S; Copitin, N; Chávez, J L; Fernández, A M; García, F; Tato, P; Molinari, J L

2017-03-01

Seizures, headache, depression and neurological deficits are the signs and symptoms most frequently reported in human neurocysticercosis. However, the cause of the associated learning and memory deficits is unknown. Here, we used Taenia crassiceps infection in mice as a model of human cysticercosis. The effects of T. crassiceps metacestode infection or T. crassiceps metacestode factor (MF) treatment on mouse hippocampal cells were studied; control mice were included. At 45 days after infection or treatment of the mice with MF, all mice were anaesthetized and perfused transcardially with saline followed by phosphate-buffered 10% formalin. Then the brains were carefully removed. Coronal sections stained using several techniques were analysed. Extensive and significant apoptosis was found in the experimental animals, mainly in the dentate gyrus, CA1, CA2, CA3 and neighbouring regions, in comparison with the apparently intact cells from control mice (P < 0.01). These results suggest that neurological deficits, especially the learning and memory deficits, may be generated by extensive apoptosis of hippocampal cells.

Photoelectrochemical cell including Ga(Sb.sub.x)N.sub.1-x semiconductor electrode

DOEpatents

Menon, Madhu; Sheetz, Michael; Sunkara, Mahendra Kumar; Pendyala, Chandrashekhar; Sunkara, Swathi; Jasinski, Jacek B.

2017-09-05

The composition of matter comprising Ga(Sb.sub.x)N.sub.1-x where x=0.01 to 0.06 is characterized by a band gap between 2.4 and 1.7 eV. A semiconductor device includes a semiconductor layer of that composition. A photoelectric cell includes that semiconductor device.

Mechanisms of regulation of cell-mediated immunity. III. The characterization of azobenzenearsonate-specific suppressor T-cell- derived-suppressor factors

PubMed Central

1979-01-01

Delayed type hypersensitivity to the hapten azobenzenearsonate (ABA) can be induced and suppressed by the administration of hapten-coupled syngeneic spleen cells by the appropriate route. Suppressor T cells stimulated by the intravenous administration of ABA-coupled spleen cells have been shown to produce a discrete subcellular factor(s) which is capable of suppressing delayed type hypersensitivity to azobenzenearsonate in the mouse. Such suppressor factors may be produced by the mechanical disruption of suppressor cells or by placing such suppressor cells in culture for 24 h. The suppressor factor(s) (SF) derived from ABA-specific suppressor cells exhibit biological specificity for the suppression of ABA delayed type hypersensitivity (DTH), but not trinitro-phenyl DTH, as well as the capacity to bind to ABA immunoadsorbents. Passage of suppressor factor(s) over reverse immunoadsorbents utilizing a rabbit anti-mouse F(ab')2 antiserum demonstrated that the antigen-specific T-cell derived SF does not bear conventional immunoglobulin markers. The suppressor factor(s) are not immunoglobulin molecules was further demonstrated by the inability of anti-ABA antibodies to suppress ABA DTH. Gel filtration of ABA suppressor factor(s) showed that the majority of the suppressive activity was present in a fraction with molecular weight ranging between 6.8 x 10(4) and 3.3 x 10(4) daltons. We also analyzed for the presence of determinants encoded by the H-2 major histocompatibility complex (MHC) and found that immunoadsorbents prepared utilizing antisera capable of interacting with gene products of the whole or selected gene regions of H-2 MHC, i.e., B10.D2 anti-B10.A and B10 anti- B10.A immunoadsorbents, retained the suppressive activity of ABA-SF. Elution of such columns with glycine HCl buffers (pH 2.8) permitted recovery of specific suppressive activity. Taken collectively such data supports the notion that suppressor T-cell-derived ABA suppressor factors have antigen

Human interleukin for DA cells or leukemia inhibitory factor is released by Vero cells in human embryo coculture.

PubMed

Papaxanthos-Roche, A; Taupin, J L; Mayer, G; Daniel, J Y; Moreau, J F

1994-09-01

In the light of the newly discovered implications of human interleukin for DA cells and leukemia inhibitory factor in embryology, we searched for the presence of this soluble cytokine in the supernatant of Vero cell coculture systems. Using a bioassay as well as a specific ELISA, we demonstrated that Vero cells are able to release large quantities of human interleukin for DA cells and leukemia inhibitory factor in the embryo-growing medium of such cocultures.

Transcription factor-mediated reprogramming toward hematopoietic stem cells

PubMed Central

Ebina, Wataru; Rossi, Derrick J

2015-01-01

De novo generation of human hematopoietic stem cells (HSCs) from renewable cell types has been a long sought-after but elusive goal in regenerative medicine. Paralleling efforts to guide pluripotent stem cell differentiation by manipulating developmental cues, substantial progress has been made recently toward HSC generation via combinatorial transcription factor (TF)-mediated fate conversion, a paradigm established by Yamanaka's induction of pluripotency in somatic cells by mere four TFs. This review will integrate the recently reported strategies to directly convert a variety of starting cell types toward HSCs in the context of hematopoietic transcriptional regulation and discuss how these findings could be further developed toward the ultimate generation of therapeutic human HSCs. PMID:25712209

Risk Factors for 30-Day Readmission in Adults with Sickle Cell Disease.

PubMed

Brodsky, Max A; Rodeghier, Mark; Sanger, Maureen; Byrd, Jeannie; McClain, Brandi; Covert, Brittany; Roberts, Dionna O; Wilkerson, Karina; DeBaun, Michael R; Kassim, Adetola A

2017-05-01

Readmission to the hospital within 30 days is a measure of quality care; however, only few modifiable risk factors for 30-day readmission in adults with sickle cell disease are known. We performed a retrospective review of the medical records of adults with sickle cell disease at a tertiary care center, to identify potentially modifiable risk factors for 30-day readmission due to vasoocclusive pain episodes. A total of 88 patients ≥18 years of age were followed for 3.5 years between 2010 and 2013, for 158 first admissions for vasoocclusive pain episodes. Of these, those subsequently readmitted (cases) or not readmitted (controls) within 30 days of their index admissions were identified. Seven risk factors were included in a multivariable model to predict readmission: age, sex, hemoglobin phenotype, median oxygen saturation level, listing of primary care provider, type of health insurance, and number of hospitalized vasoocclusive pain episodes in the prior year. Mean age at admission was 31.7 (18-59) years; median time to readmission was 11 days (interquartile range 20 days). Absence of a primary care provider listed in the electronic medical record (odds ratio 0.38; 95% confidence interval, 0.16-0.91; P = .030) and the number of vasoocclusive pain episodes requiring hospitalization in the prior year were significant risk factors for 30-day readmission (odds ratio 1.30; 95% confidence interval, 1.16-1.44; P <.001). Improved discharge planning and ensuring access to a primary care provider may decrease the 30-day readmission rate in adults with sickle cell disease. Copyright © 2017 Elsevier Inc. All rights reserved.

Induction of endothelial cell proliferation by angiogenic factors released by activated monocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pakala, Rajbabu; Watanabe, Takuya; Benedict, Claude R

2002-06-01

Introduction: Cell-cell interaction is an essential component of atherosclerotic plaque development. Activated monocytes appear to play a central role in the development of atherosclerosis, not only through foam cell formation but also via the production of various growth factors that induce proliferation of different cell types that are involved in the plaque development. Using serum free co-culture method, we determined the effect of monocytes on endothelial cell proliferation. Methods: Endothelial cell proliferation is determined by the amount of [{sup 3}H]thymidine incorporated in to the DNA. Basic fibroblast growth factor (b-FGF), vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8) levels inmore » the conditioned medium were determined by ELISA. Results: Conditioned medium from unactivated monocytes partially inhibited endothelial cell proliferation, whereas conditioned medium from activated monocytes promoted endothelial cell proliferation. The mitogenic effect of conditioned medium derived from activated monocytes is due to the presence of b-FGF, VEGF and IL-8. Neutralizing antibodies against b-FGF, VEGF and IL-8 partially reversed the mitogenic effect of conditioned medium derived from activated monocytes. When b-FGF, VEGF and IL-8 were immunoprecipitated from conditioned medium derived from activated monocytes, it is less mitogenic to endothelial cells. Conclusion: Activated monocytes may play an important role in the development of atherosclerotic plaque by producing endothelial cell growth factors.« less

Mutations in the Primary Sigma Factor σA and Termination Factor Rho That Reduce Susceptibility to Cell Wall Antibiotics

PubMed Central

Lee, Yong Heon

2014-01-01

Combinations of glycopeptides and β-lactams exert synergistic antibacterial activity, but the evolutionary mechanisms driving resistance to both antibiotics remain largely unexplored. By repeated subculturing with increasing vancomycin (VAN) and cefuroxime (CEF) concentrations, we isolated an evolved strain of the model bacterium Bacillus subtilis with reduced susceptibility to both antibiotics. Whole-genome sequencing revealed point mutations in genes encoding the major σ factor of RNA polymerase (sigA), a cell shape-determining protein (mreB), and the ρ termination factor (rho). Genetic-reconstruction experiments demonstrated that the G-to-C substitution at position 336 encoded by sigA (sigAG336C), in the domain that recognizes the −35 promoter region, is sufficient to reduce susceptibility to VAN and works cooperatively with the rhoG56C substitution to increase CEF resistance. Transcriptome analyses revealed that the sigAG336C substitution has wide-ranging effects, including elevated expression of the general stress σ factor (σB) regulon, which is required for CEF resistance, and decreased expression of the glpTQ genes, which leads to fosfomycin (FOS) resistance. Our findings suggest that mutations in the core transcriptional machinery may facilitate the evolution of resistance to multiple cell wall antibiotics. PMID:25112476

Growth differentiation factor 9 signaling requires ERK1/2 activity in mouse granulosa and cumulus cells.

PubMed

Sasseville, Maxime; Ritter, Lesley J; Nguyen, Thao M; Liu, Fang; Mottershead, David G; Russell, Darryl L; Gilchrist, Robert B

2010-09-15

Ovarian folliculogenesis is driven by the combined action of endocrine cues and paracrine factors. The oocyte secretes powerful mitogens, such as growth differentiation factor 9 (GDF9), that regulate granulosa cell proliferation, metabolism, steroidogenesis and differentiation. This study investigated the role of the epidermal growth factor receptor (EGFR)-extracellular signal-regulated kinase 1 and 2 (ERK1/2; also known as MAPK3/1) signaling pathway on GDF9 action on granulosa cells. Results show that mitogenic action of the oocyte is prevented by pharmacological inhibition of the EGFR-ERK1/2 pathway. Importantly, EGFR-ERK1/2 activity as well as rous sarcoma oncogene family kinases (SFK) are required for signaling through SMADs, mediating GDF9, activin A and TGFbeta1 mitogenic action in granulosa cells. GDF9 could not activate ERK1/2 or affect EGF-stimulated ERK1/2 in granulosa cells. However, induction of the SMAD3-specific CAGA reporter by GDF9 in granulosa cells required active EGFR, SFKs and ERK1/2 as did GDF9-responsive gene expression. Finally, the EGFR-SFKs-ERK1/2 pathway was shown to be required for the maintenance of phosphorylation of the SMAD3 linker region. Together our results suggest that receptivity of granulosa cells to oocyte-secreted factors, including GDF9, is regulated by the level of activation of the EGFR and resulting ERK1/2 activity, through the requisite permissive phosphorylation of SMAD3 in the linker region. Our results indicate that oocyte-secreted TGFbeta-like ligands and EGFR-ERK1/2 signaling are cooperatively required for the unique granulosa cell response to the signal from oocytes mediating granulosa cell survival and proliferation and hence the promotion of follicle growth and ovulation.

Tcf3 and cell cycle factors contribute to butyrate resistance in colorectal cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chiaro, Christopher, E-mail: cchiaro@tcmedc.org; Lazarova, Darina L., E-mail: dlazarova@tcmedc.org; Bordonaro, Michael, E-mail: mbordonaro@tcmedc.org

2012-11-09

Highlights: Black-Right-Pointing-Pointer We investigate mechanisms responsible for butyrate resistance in colon cancer cells. Black-Right-Pointing-Pointer Tcf3 modulates butyrate's effects on Wnt activity and cell growth in resistant cells. Black-Right-Pointing-Pointer Tcf3 modulation of butyrate's effects differ by cell context. Black-Right-Pointing-Pointer Cell cycle factors are overexpressed in the resistant cells. Black-Right-Pointing-Pointer Reversal of altered gene expression can enhance the anti-cancer effects of butyrate. -- Abstract: Butyrate, a fermentation product of dietary fiber, inhibits clonal growth in colorectal cancer (CRC) cells dependent upon the fold induction of Wnt activity. We have developed a CRC cell line (HCT-R) that, unlike its parental cell line, HCT-116,more » does not respond to butyrate exposure with hyperactivation of Wnt signaling and suppressed clonal growth. PCR array analyses revealed Wnt pathway-related genes, the expression of which differs between butyrate-sensitive HCT-116 CRC cells and their butyrate-resistant HCT-R cell counterparts. We identified overexpression of Tcf3 as being partially responsible for the butyrate-resistant phenotype, as this DNA-binding protein suppresses the hyperinduction of Wnt activity by butyrate. Consequently, Tcf3 knockdown in HCT-R cells restores their sensitivity to the effects of butyrate on Wnt activity and clonal cell growth. Interestingly, the effects of overexpressed Tcf3 differ between HCT-116 and HCT-R cells; thus, in HCT-116 cells Tcf3 suppresses proliferation without rendering the cells resistant to butyrate. In HCT-R cells, however, the overexpression of Tcf3 inhibits Wnt activity, and the cells are still able to proliferate due to the higher expression levels of cell cycle factors, particularly those driving the G{sub 1} to S transition. Knowledge of the molecular mechanisms determining the variable sensitivity of CRC cells to butyrate may assist in developing approaches that

Microgravity inhibition of lipopolysaccharide-induced tumor necrosis factor-α expression in macrophage cells.

PubMed

Wang, Chongzhen; Luo, Haiying; Zhu, Linnan; Yang, Fan; Chu, Zhulang; Tian, Hongling; Feng, Meifu; Zhao, Yong; Shang, Peng

2014-01-01

Microgravity environments in space can cause major abnormalities in human physiology, including decreased immunity. The underlying mechanisms of microgravity-induced inflammatory defects in macrophages are unclear. RAW264.7 cells and primary mouse macrophages were used in the present study. Lipopolysaccharide (LPS)-induced cytokine expression in mouse macrophages was detected under either simulated microgravity or 1g control. Freshly isolated primary mouse macrophages and RAW264.7 cells were cultured in a standard simulated microgravity situation using a rotary cell culture system (RCCS-1) and 1g control conditions. The cytokine expression was determined by real-time PCR and ELISA assays. Western blots were used to investigate the related intracellular signals. LPS-induced tumor necrosis factor-α (TNF-α) expression, but not interleukin-1β expression, in mouse macrophages was significantly suppressed under simulated microgravity. The molecular mechanism studies showed that LPS-induced intracellular signal transduction including phosphorylation of IKK and JNK and nuclear translocation of NF-κB in macrophages was identical under normal gravity and simulated microgravity. Furthermore, TNF-α mRNA stability did not decrease under simulated microgravity. Finally, we found that heat shock factor-1 (HSF1), a known repressor of TNF-α promoter, was markedly activated under simulated microgravity. Short-term treatment with microgravity caused significantly decreased TNF-α production. Microgravity-activated HSF1 may contribute to the decreased TNF-α expression in macrophages directly caused by microgravity, while the LPS-induced NF-κB pathway is resistant to microgravity.

Rat Stem-Cell Factor Induces Splenocytes Capable Of Regenerating The Thymus

PubMed Central

Migita, Russell T.; Trebasky, Lisa D.; Housman, Jerry M.; Elliott, Gary S.; Hendren, R. Wayne; Deprince, Randolph B.; Greiner, Dale L.

1992-01-01

Cytokine regulation of prethymic T-lymphoid progenitor-cell proliferation and/or differentiation has not been well-defined, although much is known of cytokine regulation of hemopoietic stem- and progenitor-cell development. Here we use a recently identified hemopoietic growth factor, stem-cell factor (SCF) (a form of the c-kit ligand), and a transplant model of thymocyte regeneration to assess the effect of SCF on the in vivo generation of prethymic, thymocyte progenitor-cell activity. We show that recombinant rat SCF (rrSCF164 administered to weanling rats selectively induces an increase in thymocyte progenitor activity in the spleens of treated rats as compared to rats treated with vehicle, polyethylene glycol (PEG)-conjugated rat albumin, or recombinant human granulocyte colony-stimulating factor (rhG-CSF). These data demonstrate that administration of SCF in vivo affects extrathymic-origin thymocyte regenerating cells and may influence, directly or indirectly, early prethymic stages of T-cell lymphopoiesis in addition to its known effect on early stages of myelopoiesis and erythropoiesis. PMID:1285280

Accuracy of expressions for the fill factor of a solar cell in terms of open-circuit voltage and ideality factor

NASA Astrophysics Data System (ADS)

Leilaeioun, Mehdi; Holman, Zachary C.

2016-09-01

An approximate expression proposed by Green predicts the maximum obtainable fill factor (FF) of a solar cell from its open-circuit voltage (Voc). The expression was originally suggested for silicon solar cells that behave according to a single-diode model and, in addition to Voc, it requires an ideality factor as input. It is now commonly applied to silicon cells by assuming a unity ideality factor—even when the cells are not in low injection—as well as to non-silicon cells. Here, we evaluate the accuracy of the expression in several cases. In particular, we calculate the recombination-limited FF and Voc of hypothetical silicon solar cells from simulated lifetime curves, and compare the exact FF to that obtained with the approximate expression using assumed ideality factors. Considering cells with a variety of recombination mechanisms, wafer doping densities, and photogenerated current densities reveals the range of conditions under which the approximate expression can safely be used. We find that the expression is unable to predict FF generally: For a typical silicon solar cell under one-sun illumination, the error is approximately 6% absolute with an assumed ideality factor of 1. Use of the expression should thus be restricted to cells under very low or very high injection.

Technical Advance: Transcription factor, promoter, and enhancer utilization in human myeloid cells.

PubMed

Joshi, Anagha; Pooley, Christopher; Freeman, Tom C; Lennartsson, Andreas; Babina, Magda; Schmidl, Christian; Geijtenbeek, Teunis; Michoel, Tom; Severin, Jessica; Itoh, Masayoshi; Lassmann, Timo; Kawaji, Hideya; Hayashizaki, Yoshihide; Carninci, Piero; Forrest, Alistair R R; Rehli, Michael; Hume, David A

2015-05-01

The generation of myeloid cells from their progenitors is regulated at the level of transcription by combinatorial control of key transcription factors influencing cell-fate choice. To unravel the global dynamics of this process at the transcript level, we generated transcription profiles for 91 human cell types of myeloid origin by use of CAGE profiling. The CAGE sequencing of these samples has allowed us to investigate diverse aspects of transcription control during myelopoiesis, such as identification of novel transcription factors, miRNAs, and noncoding RNAs specific to the myeloid lineage. We further reconstructed a transcription regulatory network by clustering coexpressed transcripts and associating them with enriched cis-regulatory motifs. With the use of the bidirectional expression as a proxy for enhancers, we predicted over 2000 novel enhancers, including an enhancer 38 kb downstream of IRF8 and an intronic enhancer in the KIT gene locus. Finally, we highlighted relevance of these data to dissect transcription dynamics during progressive maturation of granulocyte precursors. A multifaceted analysis of the myeloid transcriptome is made available (www.myeloidome.roslin.ed.ac.uk). This high-quality dataset provides a powerful resource to study transcriptional regulation during myelopoiesis and to infer the likely functions of unannotated genes in human innate immunity. © The Author(s).

Sequential growth factor application in bone marrow stromal cell ligament engineering.

PubMed

Moreau, Jodie E; Chen, Jingsong; Horan, Rebecca L; Kaplan, David L; Altman, Gregory H

2005-01-01

In vitro bone marrow stromal cell (BMSC) growth may be enhanced through culture medium supplementation, mimicking the biochemical environment in which cells optimally proliferate and differentiate. We hypothesize that the sequential administration of growth factors to first proliferate and then differentiate BMSCs cultured on silk fiber matrices will support the enhanced development of ligament tissue in vitro. Confluent second passage (P2) BMSCs obtained from purified bone marrow aspirates were seeded on RGD-modified silk matrices. Seeded matrices were divided into three groups for 5 days of static culture, with medium supplement of basic fibroblast growth factor (B) (1 ng/mL), epidermal growth factor (E; 1 ng/mL), or growth factor-free control (C). After day 5, medium supplementation was changed to transforming growth factor-beta1 (T; 5 ng/mL) or C for an additional 9 days of culture. Real-time RT-PCR, SEM, MTT, histology, and ELISA for collagen type I of all sample groups were performed. Results indicated that BT supported the greatest cell ingrowth after 14 days of culture in addition to the greatest cumulative collagen type I expression measured by ELISA. Sequential growth factor application promoted significant increases in collagen type I transcript expression from day 5 of culture to day 14, for five of six groups tested. All T-supplemented samples surpassed their respective control samples in both cell ingrowth and collagen deposition. All samples supported spindle-shaped, fibroblast cell morphology, aligning with the direction of silk fibers. These findings indicate significant in vitro ligament development after only 14 days of culture when using a sequential growth factor approach.

Liver-enriched transcription factors uncoupled from expression of hepatic functions in hepatoma cell lines.

PubMed Central

Chaya, D; Fougère-Deschatrette, C; Weiss, M C

1997-01-01

Among the liver-enriched transcription factors identified to date, only expression of hepatocyte nuclear factor 4 (HNF4) and hepatocyte nuclear factor 1 (HNF1) is in strict correlation with hepatic differentiation in cultured rat hepatoma cells. Indeed, differentiated hepatoma cells that stably express an extensive set of adult hepatic functions express liver-enriched transcription factors, while dedifferentiated cells that have lost expression of all these hepatic functions no longer express HNF4 and HNF1. We describe a new heritable phenotype, designated as uncoupled, in which there is a spontaneous dissociation between the expression of these transcription factors and that of the hepatic functions. Cells presenting this phenotype, isolated from differentiated hepatoma cells, cease to accumulate all transcripts coding for hepatic functions but nevertheless maintain expression of HNF4 and HNF1. Transitory transfection experiments indicate that these two factors present in these cells have transcriptional activity similar to that of differentiated hepatoma cells. Characterization of the appropriate intertypic cell hybrids demonstrates that this new phenotype is recessive to the dedifferentiated state and fails to be complemented by differentiated cells. These results indicate the existence of mechanisms that inhibit transcription of genes coding for hepatocyte functions in spite of the presence of functional HNF4 and HNF1. Cells of the uncoupled phenotype present certain properties of oval cells described for pathological states of the liver. PMID:9343392

Liver-enriched transcription factors uncoupled from expression of hepatic functions in hepatoma cell lines.

PubMed

Chaya, D; Fougère-Deschatrette, C; Weiss, M C

1997-11-01

Among the liver-enriched transcription factors identified to date, only expression of hepatocyte nuclear factor 4 (HNF4) and hepatocyte nuclear factor 1 (HNF1) is in strict correlation with hepatic differentiation in cultured rat hepatoma cells. Indeed, differentiated hepatoma cells that stably express an extensive set of adult hepatic functions express liver-enriched transcription factors, while dedifferentiated cells that have lost expression of all these hepatic functions no longer express HNF4 and HNF1. We describe a new heritable phenotype, designated as uncoupled, in which there is a spontaneous dissociation between the expression of these transcription factors and that of the hepatic functions. Cells presenting this phenotype, isolated from differentiated hepatoma cells, cease to accumulate all transcripts coding for hepatic functions but nevertheless maintain expression of HNF4 and HNF1. Transitory transfection experiments indicate that these two factors present in these cells have transcriptional activity similar to that of differentiated hepatoma cells. Characterization of the appropriate intertypic cell hybrids demonstrates that this new phenotype is recessive to the dedifferentiated state and fails to be complemented by differentiated cells. These results indicate the existence of mechanisms that inhibit transcription of genes coding for hepatocyte functions in spite of the presence of functional HNF4 and HNF1. Cells of the uncoupled phenotype present certain properties of oval cells described for pathological states of the liver.

Multiple Mechanisms are Responsible for Transactivation of the Epidermal Growth Factor Receptor in Mammary Epithelial Cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rodland, Karin D.; Bollinger, Nikki; Ippolito, Danielle L.

2008-11-14

REVIEW ENTIRE DOCUMENT AT: https://pnlweb.pnl.gov/projects/bsd/ERICA%20Manuscripts%20for%20Review/KD%20Rodland%20D7E80/HMEC_transactivation_ms01_15+Figs.pdf ABSTRACT: Using a single nontransformed strain of human mammary epithelial cells, we found that the ability of multiple growth factors and cytokines to induce ERK phosphorylation was dependent on EGFR activity. These included lysophosphatidic acid (LPA), uridine triphosphate, growth hormone, vascular endothelial growth factor, insulin-like growth factor-1 (IGF-1), and tumor necrosis factoralpha. In contrast, hepatocyte growth factor could stimulate ERK phosphorylation independent of EGFR activity...

Neural progenitor cell implants modulate vascular endothelial growth factor and brain-derived neurotrophic factor expression in rat axotomized neurons.

PubMed

Talaverón, Rocío; Matarredona, Esperanza R; de la Cruz, Rosa R; Pastor, Angel M

2013-01-01

Axotomy of central neurons leads to functional and structural alterations which largely revert when neural progenitor cells (NPCs) are implanted in the lesion site. The new microenvironment created by NPCs in the host tissue might modulate in the damaged neurons the expression of a high variety of molecules with relevant roles in the repair mechanisms, including neurotrophic factors. In the present work, we aimed to analyze changes in neurotrophic factor expression in axotomized neurons induced by NPC implants. For this purpose, we performed immunofluorescence followed by confocal microscopy analysis for the detection of vascular endothelial growth factor (VEGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3) and nerve growth factor (NGF) on brainstem sections from rats with axotomy of abducens internuclear neurons that received NPC implants (implanted group) or vehicle injections (axotomized group) in the lesion site. Control abducens internuclear neurons were strongly immunoreactive to VEGF and BDNF but showed a weak staining for NT-3 and NGF. Comparisons between groups revealed that lesioned neurons from animals that received NPC implants showed a significant increase in VEGF content with respect to animals receiving vehicle injections. However, the immunoreactivity for BDNF, which was increased in the axotomized group as compared to control, was not modified in the implanted group. The modifications induced by NPC implants on VEGF and BDNF content were specific for the population of axotomized abducens internuclear neurons since the neighboring abducens motoneurons were not affected. Similar levels of NT-3 and NGF immunolabeling were obtained in injured neurons from axotomized and implanted animals. Among all the analyzed neurotrophic factors, only VEGF was expressed by the implanted cells in the lesion site. Our results point to a role of NPC implants in the modulation of neurotrophic factor expression by lesioned central neurons, which might

Control of germline stem cell self-renewal and differentiation in the Drosophila ovary: concerted actions of niche signals and intrinsic factors.

PubMed

Xie, Ting

2013-01-01

In the Drosophila ovary, germline stem cells (GSCs) physically interact with their niche composed of terminal filament cells, cap cells, and possibly GSC-contacting escort cells (ECs). A GSC divides to generate a self-renewing stem cell that remains in the niche and a differentiating daughter that moves away from the niche. The GSC niche provides a bone morphogenetic protein (BMP) signal that maintains GSC self-renewal by preventing stem cell differentiation via repression of the differentiation-promoting gene bag of marbles (bam). In addition, it expresses E-cadherin, which mediates cell adhesion for anchoring GSCs in the niche, enabling continuous self-renewal. GSCs themselves also express different classes of intrinsic factors, including signal transducers, transcription factors, chromatin remodeling factors, translation regulators, and miRNAs, which control self-renewal by strengthening interactions with the niche and repressing various differentiation pathways. Differentiated GSC daughters, known as cystoblasts (CBs), also express distinct classes of intrinsic factors to inhibit self-renewal and promote germ cell differentiation. Surprisingly, GSC progeny are also dependent on their surrounding ECs for proper differentiation at least partly by preventing BMP from diffusing to the differentiated germ cell zone and by repressing ectopic BMP expression. Therefore, both GSC self-renewal and CB differentiation are controlled by collaborative actions of extrinsic signals and intrinsic factors. Copyright © 2012 Wiley Periodicals, Inc.

Bacillus subtilis extracytoplasmic function (ECF) sigma factors and defense of the cell envelope.

PubMed

Helmann, John D

2016-04-01

Bacillus subtilis provides a model for investigation of the bacterial cell envelope, the first line of defense against environmental threats. Extracytoplasmic function (ECF) sigma factors activate genes that confer resistance to agents that threaten the integrity of the envelope. Although their individual regulons overlap, σ(W) is most closely associated with membrane-active agents, σ(X) with cationic antimicrobial peptide resistance, and σ(V) with resistance to lysozyme. Here, I highlight the role of the σ(M) regulon, which is strongly induced by conditions that impair peptidoglycan synthesis and includes the core pathways of envelope synthesis and cell division, as well as stress-inducible alternative enzymes. Studies of these cell envelope stress responses provide insights into how bacteria acclimate to the presence of antibiotics. Copyright © 2016 Elsevier Ltd. All rights reserved.

Hepatocyte growth factor/scatter factor enhances the invasion of mesothelioma cell lines and the expression of matrix metalloproteinases

PubMed Central

Harvey, P; Clark, I M; Jaurand, M-C; Warn, R M; Edwards, D R

2000-01-01

Hepatocyte growth factor/scatter factor (HGF/SF) is a multifunctional factor involved both in development and tissue repair, as well as pathological processes such as cancer and metastasis. It has been identified in vivo in many types of tumours together with its tyrosine kinase receptor, Met. We show here that exogenous HGF/SF acts as a strong chemoattractant for human mesothelioma cell lines. The factor also enhanced cell adhesion to and invasion into Matrigel. The mesothelioma cell lines synthesized a panel of matrix metalloproteinases critical for tumour progression such as MMP-1, 2, 3, 9 and membrane-bound MT1-MMP. HGF/SF stimulated the expression of MMP-1, 9 and MT1-MMP and had a slight effect on expression of the MMP inhibitor TIMP-1 but not TIMP-2. However, there was no simple correlation between the levels of MMPs and TIMPs of the cell lines and their different invasion properties or between HGF/SF stimulatory effects on MMP expression and invasion. In addition, effects of protease inhibitors on invasion suggested that serine proteases were also expressed in human mesothelioma cell lines and were involved in HGF/SF-induced invasion. The results show a predominant role for HGF/SF in mesothelioma cell invasion, stimulating simultaneously adhesion, motility, invasion and regulation of MMP and TIMP levels. © 2000 Cancer Research Campaign PMID:11027427

The Nell-1 Growth Factor Stimulates Bone Formation by Purified Human Perivascular Cells

PubMed Central

Zhang, Xinli; Péault, Bruno; Chen, Weiwei; Li, Weiming; Corselli, Mirko; James, Aaron W.; Lee, Min; Siu, Ronald K.; Shen, Pang; Zheng, Zhong; Shen, Jia; Kwak, Jinny; Zara, Janette N.; Chen, Feng; Zhang, Hong; Yin, Zack; Wu, Ben; Ting, Kang

2011-01-01

The search for novel sources of stem cells other than bone marrow mesenchymal stem cells (MSCs) for bone regeneration and repair has been a critical endeavor. We previously established an effective protocol to homogeneously purify human pericytes from multiple fetal and adult tissues, including adipose, bone marrow, skeletal muscle, and pancreas, and identified pericytes as a primitive origin of human MSCs. In the present study, we further characterized the osteogenic potential of purified human pericytes combined with a novel osteoinductive growth factor, Nell-1. Purified pericytes grown on either standard culture ware or human cancellous bone chip (hCBC) scaffolds exhibited robust osteogenic differentiation in vitro. Using a nude mouse muscle pouch model, pericytes formed significant new bone in vivo as compared to scaffold alone (hCBC). Moreover, Nell-1 significantly increased pericyte osteogenic differentiation, both in vitro and in vivo. Interestingly, Nell-1 significantly induced pericyte proliferation and was observed to have pro-angiogenic effects, both in vitro and in vivo. These studies suggest that pericytes are a potential new cell source for future efforts in skeletal regenerative medicine, and that Nell-1 is a candidate growth factor able to induce pericyte osteogenic differentiation. PMID:21615216

Effects of growth factors and glucosamine on porcine mandibular condylar cartilage cells and hyaline cartilage cells for tissue engineering applications.

PubMed

Wang, Limin; Detamore, Michael S

2009-01-01

Temporomandibular joint (TMJ) condylar cartilage is a distinct cartilage that has both fibrocartilaginous and hyaline-like character, with a thin proliferative zone that separates the fibrocartilaginous fibrous zone at the surface from the hyaline-like mature and hypertrophic zones below. In this study, we compared the effects of insulin-like growth factor-I (IGF-I), basic fibroblast growth factor (bFGF), transforming growth factor beta1 (TGF-beta1), and glucosamine sulphate on porcine TMJ condylar cartilage and ankle cartilage cells in monolayer culture. In general, TMJ condylar cartilage cells proliferated faster than ankle cartilage cells, while ankle cells produced significantly greater amounts of glycosaminoglycans (GAGs) and collagen than TMJ condylar cartilage cells. IGF-I and bFGF were potent stimulators of TMJ cell proliferation, while no signals statistically outperformed controls for ankle cell proliferation. IGF-I was the most effective signal for GAG production with ankle cells, and the most potent upregulator of collagen synthesis for both cell types. Glucosamine sulphate promoted cell proliferation and biosynthesis at specific concentrations and outperformed growth factors in certain instances. In conclusion, hyaline cartilage cells had lower cell numbers and superior biosynthesis compared to TMJ condylar cartilage cells, and we have found IGF-I at 100 ng/mL and glucosamine sulphate at 100 microg/mL to be the most effective signals for these cells under the prescribed conditions.

Tissue and cell-type co-expression networks of transcription factors and wood component genes in Populus trichocarpa.

PubMed

Shi, Rui; Wang, Jack P; Lin, Ying-Chung; Li, Quanzi; Sun, Ying-Hsuan; Chen, Hao; Sederoff, Ronald R; Chiang, Vincent L

2017-05-01

Co-expression networks based on transcriptomes of Populus trichocarpa major tissues and specific cell types suggest redundant control of cell wall component biosynthetic genes by transcription factors in wood formation. We analyzed the transcriptomes of five tissues (xylem, phloem, shoot, leaf, and root) and two wood forming cell types (fiber and vessel) of Populus trichocarpa to assemble gene co-expression subnetworks associated with wood formation. We identified 165 transcription factors (TFs) that showed xylem-, fiber-, and vessel-specific expression. Of these 165 TFs, 101 co-expressed (correlation coefficient, r > 0.7) with the 45 secondary cell wall cellulose, hemicellulose, and lignin biosynthetic genes. Each cell wall component gene co-expressed on average with 34 TFs, suggesting redundant control of the cell wall component gene expression. Co-expression analysis showed that the 101 TFs and the 45 cell wall component genes each has two distinct groups (groups 1 and 2), based on their co-expression patterns. The group 1 TFs (44 members) are predominantly xylem and fiber specific, and are all highly positively co-expressed with the group 1 cell wall component genes (30 members), suggesting their roles as major wood formation regulators. Group 1 TFs include a lateral organ boundary domain gene (LBD) that has the highest number of positively correlated cell wall component genes (36) and TFs (47). The group 2 TFs have 57 members, including 14 vessel-specific TFs, and are generally less correlated with the cell wall component genes. An exception is a vessel-specific basic helix-loop-helix (bHLH) gene that negatively correlates with 20 cell wall component genes, and may function as a key transcriptional suppressor. The co-expression networks revealed here suggest a well-structured transcriptional homeostasis for cell wall component biosynthesis during wood formation.

High Myeloperoxidase Positive Cell Infiltration in Colorectal Cancer Is an Independent Favorable Prognostic Factor

PubMed Central

Eppenberger-Castori, Serenella; Zlobec, Inti; Viehl, Carsten T.; Frey, Daniel M.; Nebiker, Christian A.; Rosso, Raffaele; Zuber, Markus; Amicarella, Francesca; Iezzi, Giandomenica; Sconocchia, Giuseppe; Heberer, Michael; Lugli, Alessandro; Tornillo, Luigi; Oertli, Daniel

2013-01-01

Background Colorectal cancer (CRC) infiltration by adaptive immune system cells correlates with favorable prognosis. The role of the innate immune system is still debated. Here we addressed the prognostic impact of CRC infiltration by neutrophil granulocytes (NG). Methods A TMA including healthy mucosa and clinically annotated CRC specimens (n = 1491) was stained with MPO and CD15 specific antibodies. MPO+ and CD15+ positive immune cells were counted by three independent observers. Phenotypic profiles of CRC infiltrating MPO+ and CD15+ cells were validated by flow cytometry on cell suspensions derived from enzymatically digested surgical specimens. Survival analysis was performed by splitting randomized data in training and validation subsets. Results MPO+ and CD15+ cell infiltration were significantly correlated (p<0.0001; r = 0.76). However, only high density of MPO+ cell infiltration was associated with significantly improved survival in training (P = 0.038) and validation (P = 0.002) sets. In multivariate analysis including T and N stage, vascular invasion, tumor border configuration and microsatellite instability status, MPO+ cell infiltration proved an independent prognostic marker overall (P = 0.004; HR = 0.65; CI:±0.15) and in both training (P = 0.048) and validation (P = 0.036) sets. Flow-cytometry analysis of CRC cell suspensions derived from clinical specimens showed that while MPO+ cells were largely CD15+/CD66b+, sizeable percentages of CD15+ and CD66b+ cells were MPO−. Conclusions High density MPO+ cell infiltration is a novel independent favorable prognostic factor in CRC. PMID:23734221

Synergistic binding of transcription factors to cell-specific enhancers programs motor neuron identity

PubMed Central

Mazzoni, Esteban O; Mahony, Shaun; Closser, Michael; Morrison, Carolyn A; Nedelec, Stephane; Williams, Damian J; An, Disi; Gifford, David K; Wichterle, Hynek

2013-01-01

Efficient transcriptional programming promises to open new frontiers in regenerative medicine. However, mechanisms by which programming factors transform cell fate are unknown, preventing more rational selection of factors to generate desirable cell types. Three transcription factors, Ngn2, Isl1 and Lhx3, were sufficient to program rapidly and efficiently spinal motor neuron identity when expressed in differentiating mouse embryonic stem cells. Replacement of Lhx3 by Phox2a led to specification of cranial, rather than spinal, motor neurons. Chromatin immunoprecipitation–sequencing analysis of Isl1, Lhx3 and Phox2a binding sites revealed that the two cell fates were programmed by the recruitment of Isl1-Lhx3 and Isl1-Phox2a complexes to distinct genomic locations characterized by a unique grammar of homeodomain binding motifs. Our findings suggest that synergistic interactions among transcription factors determine the specificity of their recruitment to cell type–specific binding sites and illustrate how a single transcription factor can be repurposed to program different cell types. PMID:23872598

Stem cell factor supports migration in canine mesenchymal stem cells.

PubMed

Enciso, Nathaly; Ostronoff, Luciana L K; Mejías, Guillermo; León, Leticia G; Fermín, María Luisa; Merino, Elena; Fragio, Cristina; Avedillo, Luis; Tejero, Concepción

2018-03-01

Adult Mesenchymal Stem Cells (MSC) are cells that can be defined as multipotent cells able to differentiate into diverse lineages, under appropriate conditions. These cells have been widely used in regenerative medicine, both in preclinical and clinical settings. Initially discovered in bone marrow, MSC can now be isolated from a wide spectrum of adult and foetal tissues. Studies to evaluate the therapeutic potential of these cells are based on their ability to arrive to damaged tissues. In this paper we have done a comparative study analyzing proliferation, surface markers and OCT4, SOX9, RUNX2, PPARG genes expression in MSC cells from Bone marrow (BMMSC) and Adipose tissue (ASC). We also analyzed the role of Stem Cell Factor (SCF) on MSC proliferation and on ASCs metalloproteinases MMP-2, MMP-9 secretion. Healthy dogs were used as BMMSC donors, and ASC were collected from omentum during elective ovariohysterectomy surgery. Both cell types were cultured in IMDM medium with or without SCF, 10% Dog Serum (DS), and incubated at 38 °C with 5% CO2. Growth of BMMSCs and ASCs was exponential until 25-30 days. Flow citometry of MSCs revealed positive results for CD90 and negative for CD34, CD45 and MCH-II. Genes were evaluated by RT-PCR and metalloproteinases by zymografy. Our findings indicate morphological and immunological similarities as well as expression of genes from both origins on analyzed cells. Furthermore, SCF did not affect proliferation of MSCs, however it up-regulated MMP-2 and MMP-9 secretion in ASCs. These results suggest that metalloproteinases are possibly essential molecules pivoting migration.

Factors associated with a primary surgical approach for sinonasal squamous cell carcinoma.

PubMed

Cracchiolo, Jennifer R; Patel, Krupa; Migliacci, Jocelyn C; Morris, Luc T; Ganly, Ian; Roman, Benjamin R; McBride, Sean M; Tabar, Viviane S; Cohen, Marc A

2018-03-01

Primary surgery is the preferred treatment of T1-T4a sinonasal squamous cell carcinoma (SNSCC). Patients with SNSCC in the National Cancer Data Base (NCDB) were analyzed. Factors that contributed to selecting primary surgical treatment were examined. Overall survival (OS) in surgical patients was analyzed. Four-thousand seven hundred and seventy patients with SNSCC were included. In T1-T4a tumors, lymph node metastases, maxillary sinus location, and treatment at high-volume centers were associated with selecting primary surgery. When primary surgery was utilized, tumor factors and positive margin guided worse OS. Adjuvant therapy improved OS in positive margin resection and advanced T stage cases. Tumor and non-tumor factors are associated with selecting surgery for the treatment of SNSCC. When surgery is selected, tumor factors drive OS. Negative margin resection should be the goal of a primary surgical approach. When a positive margin resection ensues, adjuvant therapy may improve OS. © 2017 Wiley Periodicals, Inc.

Epidermal Growth Factor Increases LRF/Pokemon Expression in Human Prostate Cancer Cells

PubMed Central

Aggarwal, Himanshu; Aggarwal, Anshu; Agrawal, Devendra K.

2011-01-01

Leukemia/lymphoma related factor/POK erythroid myeloid ontogenic factor (LRF/Pokemon) is a member of the POK family of proteins that promotes oncogenesis in several forms of cancer. Recently, we found higher LRF expression in human breast and prostate carcinomas compared to the corresponding normal tissues. The aim of this study was to examine the regulation of LRF expression in human prostate cells. Epidermal growth factor (EGF) and its receptors mediate several tumorigenic cascades that regulate cell differentiation, proliferation, migration and survival of prostate cancer cells. There was significantly higher level of LRF expression in the nucleus of LNCaP and PC-3 cells than RWPE-1 cells. A significant increase in LRF expression was observed with increasing doses of EGF in more aggressive and androgen-sensitive prostate cancer cells suggesting that EGF signaling pathway is critical in upregulating the expression of LRF/Pokemon to promote oncogenesis. PMID:21640721

Helicobacter pylori induces vascular endothelial growth factor production in gastric epithelial cells through hypoxia-inducible factor-1α-dependent pathway.

PubMed

Kang, Min-Jung; Song, Eun-Jung; Kim, Bo-Yeon; Kim, Dong-Jae; Park, Jong-Hwan

2014-12-01

Although Helicobacter pylori have been known to induce vascular endothelial growth factor (VEGF) production in gastric epithelial cells, the precise mechanism for cellular signaling is incompletely understood. In this study, we investigated the role of bacterial virulence factor and host cellular signaling in VEGF production of H. pylori-infected gastric epithelial cells. We evaluated production of VEGF, activation of nuclear factor nuclear factor-kappaB (NF-κB) and mitogen-activated protein kinases (MAPKs) and hypoxia-inducible factor-1α (HIF-1α) stabilization in gastric epithelial cells infected with H. pylori WT or isogenic mutants deficient in type IV secretion system (T4SS). H. pylori induced VEGF production in gastric epithelial cells via both T4SS-dependent and T4SS-independent pathways, although T4SS-independent pathway seems to be the dominant signaling. The inhibitor assay implicated that activation of NF-κB and MAPKs is dispensable for H. pylori-induced VEGF production in gastric epithelial cells. H. pylori led to HIF-1α stabilization in gastric epithelial cells independently of T4SS, NF-κB, and MAPKs, which was essential for VEGF production in these cells. N-acetyl-cysteine (NAC), a reactive oxygen species (ROS) inhibitor, treatment impaired H. pylori-induced HIF-1α stabilization and VEGF production in gastric epithelial cells. We defined the important role of ROS-HIF-1α axis in VEGF production of H. pylori-infected gastric epithelial cells, and bacterial T4SS has a minor role in H. pylori-induced VEGF production of gastric epithelial cells. © 2014 John Wiley & Sons Ltd.

[Regulation of in vitro and in vivo differentiation of mouse embryonic stem cells, embryonic germ cells, and teratocarcinoma cells by TGFb family signaling factors].

PubMed

Gordeeva, O F; Nikonova, T M; Lifantseva, N V

2009-01-01

The activity of specific signaling and transcription factors determines the cell fate in normal development and in tumor transformation. The transcriptional profiles of gene-components of different branches of TGFbeta family signaling pathways were studied in experimental models of initial stages of three-dimensional in vitro differentiation of embryonic stem cells, embryonic germ cells and teratocarcinoma cells and in teratomas and teratocarcinomas developed after their transplantation into immunodeficient Nude mice. Gene profile analysis of studied cell systems have revealed that expression patterns of ActivinA, Nodal, Lefty1, Lefty2, TGF TGFbeta1, BMP4, and GDF were identical in pluripotent stem cells whereas the mRNAs of all examined genes with the exception of Inhibin betaA/ActivinA were detected in the teratocarcinoma cells. These results indicate that differential activity of signaling pathways of the TGFbeta family factors regulates pluripotent state maintenance and pluripotent stem cell differentiation into the progenitors of three germ layers and extraembryonic structures and that normal expression pattern of TGFbeta family factors is rearranged in embryonic teratocarcinoma cells during tumor growth in vitro and in vivo.

Photoelectrochemical cells including chalcogenophosphate photoelectrodes

NASA Technical Reports Server (NTRS)

Reichman, B.; Byvik, C. E. (Inventor)

1984-01-01

Photoelectrochemical cells employing chalcogenophosphate (MPX3) photoelectrodes are described where M is selected from the group of transition metal series of elements beginning with scandium (atomic number 21) through germanium (atomic number 32) yttrium (atomic number 39) through antimony (atomic number 51) and lanthanum (atomic number 57) through polonium (atomic number 84); P is phosphorus; and X is selected from the chalogenide series consisting of sulfur, selenium, and tellurium. These compounds have bandgaps in the desirable range from 2.0 eV to 2.2 eV for the photoelectrolysis of water and are stable when used as photoelectrodes for the same.

Macrophages control vascular stem/progenitor cell plasticity through tumor necrosis factor-α-mediated nuclear factor-κB activation.

PubMed

Wong, Mei Mei; Chen, Yikuan; Margariti, Andriani; Winkler, Bernhard; Campagnolo, Paola; Potter, Claire; Hu, Yanhua; Xu, Qingbo

2014-03-01

Vascular lineage differentiation of stem/progenitor cells can contribute to both tissue repair and exacerbation of vascular diseases such as in vein grafts. The role of macrophages in controlling vascular progenitor differentiation is largely unknown and may play an important role in graft development. This study aims to identify the role of macrophages in vascular stem/progenitor cell differentiation and thereafter elucidate the mechanisms that are involved in the macrophage- mediated process. We provide in vitro evidence that macrophages can induce endothelial cell (EC) differentiation of the stem/progenitor cells while simultaneously inhibiting their smooth muscle cell differentiation. Mechanistically, both effects were mediated by macrophage-derived tumor necrosis factor-α (TNF-α) via TNF-α receptor 1 and canonical nuclear factor-κB activation. Although the overexpression of p65 enhanced EC (or attenuated smooth muscle cell) differentiation, p65 or TNF-α receptor 1 knockdown using lentiviral short hairpin RNA inhibited EC (or rescued smooth muscle cell) differentiation in response to TNF-α. Furthermore, TNF-α-mediated EC differentiation was driven by direct binding of nuclear factor-κB (p65) to specific VE-cadherin promoter sequences. Subsequent experiments using an ex vivo decellularized vessel scaffold confirmed an increase in the number of ECs and reduction in smooth muscle cell marker expression in the presence of TNF-α. The lack of TNF-α in a knockout mouse model of vein graft decreased endothelialization and significantly increased thrombosis formation. Our study highlights the role of macrophages in directing vascular stem/progenitor cell lineage commitment through TNF-α-mediated TNF-α receptor 1 and nuclear factor-κB activation that is likely required for endothelial repair in vascular diseases such as vein graft.

A network of heterochronic genes including Imp1 regulates temporal changes in stem cell properties

PubMed Central

Nishino, Jinsuke; Kim, Sunjung; Zhu, Yuan; Zhu, Hao; Morrison, Sean J

2013-01-01

Stem cell properties change over time to match the changing growth and regeneration demands of tissues. We showed previously that adult forebrain stem cell function declines during aging because of increased expression of let-7 microRNAs, evolutionarily conserved heterochronic genes that reduce HMGA2 expression. Here we asked whether let-7 targets also regulate changes between fetal and adult stem cells. We found a second let-7 target, the RNA binding protein IMP1, that is expressed by fetal, but not adult, neural stem cells. IMP1 expression was promoted by Wnt signaling and Lin28a expression and opposed by let-7 microRNAs. Imp1-deficient neural stem cells were prematurely depleted in the dorsal telencephalon due to accelerated differentiation, impairing pallial expansion. IMP1 post-transcriptionally inhibited the expression of differentiation-associated genes while promoting the expression of self-renewal genes, including Hmga2. A network of heterochronic gene products including Lin28a, let-7, IMP1, and HMGA2 thus regulates temporal changes in stem cell properties. DOI: http://dx.doi.org/10.7554/eLife.00924.001 PMID:24192035

Comparative cell cycle transcriptomics reveals synchronization of developmental transcription factor networks in cancer cells

PubMed Central

Johard, Helena; Mahdessian, Diana; Fedr, Radek; Marks, Carolyn; Medalová, Jiřina; Souček, Karel; Lundberg, Emma; Linnarsson, Sten; Bryja, Vítězslav; Sekyrova, Petra; Altun, Mikael; Andäng, Michael

2017-01-01

The cell cycle coordinates core functions such as replication and cell division. However, cell-cycle-regulated transcription in the control of non-core functions, such as cell identity maintenance through specific transcription factors (TFs) and signalling pathways remains unclear. Here, we provide a resource consisting of mapped transcriptomes in unsynchronized HeLa and U2OS cancer cells sorted for cell cycle phase by Fucci reporter expression. We developed a novel algorithm for data analysis that enables efficient visualization and data comparisons and identified cell cycle synchronization of Notch signalling and TFs associated with development. Furthermore, the cell cycle synchronizes with the circadian clock, providing a possible link between developmental transcriptional networks and the cell cycle. In conclusion we find that cell cycle synchronized transcriptional patterns are temporally compartmentalized and more complex than previously anticipated, involving genes, which control cell identity and development. PMID:29228002

Hexamethylenebisacetamide (HMBA) is a growth factor for human, ovine and porcine thyroid cells.

PubMed

Fayet, G; Amphoux-Fazekas, T; Aouani, A; Hovsépian, S

1996-03-01

Hexamethylenebisacetamide (HMBA) provokes in murine erythroleukemia cells (MELC) a commitment to terminal differentiation leading to the activation of the expression of hemoglobin. HMBA has been tested also in other cells from colon cancer, melanoma or lung cancer. However it has not yet been tested in the thyroid. We demonstrate in this paper that HMBA in kinetics and concentration-response experiments increases the proliferation of human thyroid cells isolated from Graves'-Basedow patients. It also acts like a growth factor for ovine and porcine thyroid cells, respectively, from the OVNIS line and the ATHOS line. This molecule which is a differentiating factor in the MELC system and a growth factor in human thyroid cell cultures represents a potential to get human thyroid cell lines expressing specialized functions.

Dynamic analysis of the combinatorial regulation involving transcription factors and microRNAs in cell fate decisions.

PubMed

Yan, Fang; Liu, Haihong; Liu, Zengrong

2014-01-01

P53 and E2F1 are critical transcription factors involved in the choices between different cell fates including cell differentiation, cell cycle arrest or apoptosis. Recent experiments have shown that two families of microRNAs (miRNAs), p53-responsive miR34 (miRNA-34 a, b and c) and E2F1-inducible miR449 (miRNA-449 a, b and c) are potent inducers of these different fates and might have an important role in sensitizing cancer cells to drug treatment and tumor suppression. Identifying the mechanisms responsible for the combinatorial regulatory roles of these two transcription factors and two miRNAs is an important and challenging problem. Here, based in part on the model proposed in Tongli Zhang et al. (2007), we developed a mathematical model of the decision process and explored the combinatorial regulation between these two transcription factors and two miRNAs in response to DNA damage. By analyzing nonlinear dynamic behaviors of the model, we found that p53 exhibits pulsatile behavior. Moreover, a comparison is given to reveal the subtle differences of the cell fate decision process between regulation and deregulation of miR34 on E2F1. It predicts that miR34 plays a critical role in promoting cell cycle arrest. In addition, a computer simulation result also predicts that the miR449 is necessary for apoptosis in response to sustained DNA damage. In agreement with experimental observations, our model can account for the intricate regulatory relationship between these two transcription factors and two miRNAs in the cell fate decision process after DNA damage. These theoretical results indicate that miR34 and miR449 are effective tumor suppressors and play critical roles in cell fate decisions. The work provides a dynamic mechanism that shows how cell fate decisions are coordinated by two transcription factors and two miRNAs. This article is part of a Special Issue entitled: Computational Proteomics, Systems Biology and Clinical Implications. Guest Editor: Yudong Cai

Hepatic leukemia factor promotes resistance to cell death: Implications for therapeutics and chronotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Waters, Katrina M.; Sontag, Ryan L.; Weber, Thomas J., E-mail: Thomas.Weber@pnl.gov

Physiological variation related to circadian rhythms and aberrant gene expression patterns are believed to modulate therapeutic efficacy, but the precise molecular determinants remain unclear. Here we examine the regulation of cell death by hepatic leukemia factor (HLF), which is an output regulator of circadian rhythms and is aberrantly expressed in human cancers, using an ectopic expression strategy in JB6 mouse epidermal cells and human keratinocytes. Ectopic HLF expression inhibited cell death in both JB6 cells and human keratinocytes, as induced by serum-starvation, tumor necrosis factor alpha and ionizing radiation. Microarray analysis indicates that HLF regulates a complex multi-gene transcriptional programmore » encompassing upregulation of anti-apoptotic genes, downregulation of pro-apoptotic genes, and many additional changes that are consistent with an anti-death program. Collectively, our results demonstrate that ectopic expression of HLF, an established transcription factor that cycles with circadian rhythms, can recapitulate many features associated with circadian-dependent physiological variation. - Highlights: ► Circadian-dependent physiological variation impacts therapeutic efficacy. ► Hepatic leukemia factor inhibits cell death and is a candidate circadian factor. ► Hepatic leukemia factor anti-death program is conserved in murine and human cells. ► Transcriptomics indicates the anti-death program results from a systems response.« less

Fibroblast growth factor receptor signaling is essential for lens fiber cell differentiation.

PubMed

Zhao, Haotian; Yang, Tianyu; Madakashira, Bhavani P; Thiels, Cornelius A; Bechtle, Chad A; Garcia, Claudia M; Zhang, Huiming; Yu, Kai; Ornitz, David M; Beebe, David C; Robinson, Michael L

2008-06-15

The vertebrate lens provides an excellent model to study the mechanisms that regulate terminal differentiation. Although fibroblast growth factors (FGFs) are thought to be important for lens cell differentiation, it is unclear which FGF receptors mediate these processes during different stages of lens development. Deletion of three FGF receptors (Fgfr1-3) early in lens development demonstrated that expression of only a single allele of Fgfr2 or Fgfr3 was sufficient for grossly normal lens development, while mice possessing only a single Fgfr1 allele developed cataracts and microphthalmia. Profound defects were observed in lenses lacking all three Fgfrs. These included lack of fiber cell elongation, abnormal proliferation in prospective lens fiber cells, reduced expression of the cell cycle inhibitors p27(kip1) and p57(kip2), increased apoptosis and aberrant or reduced expression of Prox1, Pax6, c-Maf, E-cadherin and alpha-, beta- and gamma-crystallins. Therefore, while signaling by FGF receptors is essential for lens fiber differentiation, different FGF receptors function redundantly.

Fibroblast growth factor-2 regulates the cell function of human dental pulp cells.

PubMed

Shimabukuro, Yoshio; Ueda, Maki; Ozasa, Masao; Anzai, Jun; Takedachi, Masahide; Yanagita, Manabu; Ito, Masako; Hashikawa, Tomoko; Yamada, Satoru; Murakami, Shinya

2009-11-01

Homeostasis and tissue repair of dentin-pulp complex are attributed to dental pulp tissue and several growth factors. Dental pulp cells play a pivotal role in homeostasis of dentin-pulp complex and tissue responses after tooth injury. Among these cytokines, fibroblast growth factor (FGF)-2 has multifunctional biologic activity and is known as a signaling molecule that induces tissue regeneration. In this study, we examined the effects of FGF-2 on growth, migration, and differentiation of human dental pulp cells (HDPC). HDPC were isolated from healthy dental pulp. Cellular response was investigated by [(3)H]-thymidine incorporation into DNA. Cytodifferentiation was examined by alkaline phosphatase (ALPase) assay and cytochemical staining of calcium by using alizarin red. Migratory activity was determined by counting the cells migrating into cleared area that had introduced with silicon block. FGF-2 activated HDPC growth and migration but suppressed ALPase activity and calcified nodule formation. Interestingly, HDPC, which had been pretreated with FGF-2, showed increased ALPase activity and calcified nodule formation when subsequently cultured without FGF-2. These results suggest that FGF-2 potentiates cell growth and accumulation of HDPC that notably did not disturb cytodifferentiation of the cells later. Thus, FGF-2 is a favorable candidate for pulp capping agent. These results provide new evidence for the possible involvement of FGF-2 not only in homeostasis but also in regeneration of dentin-pulp complex.

A critical role for transcription factor Smad4 in T cell function that is independent of transforming growth factor β receptor signaling.

PubMed

Gu, Ai-Di; Zhang, Song; Wang, Yunqi; Xiong, Hui; Curtis, Thomas A; Wan, Yisong Y

2015-01-20

Transforming growth factor-beta (TGF-β) suppresses T cell function to maintain self-tolerance and to promote tumor immune evasion. Yet how Smad4, a transcription factor component of TGF-β signaling, regulates T cell function remains unclear. Here we have demonstrated an essential role for Smad4 in promoting T cell function during autoimmunity and anti-tumor immunity. Smad4 deletion rescued the lethal autoimmunity resulting from transforming growth factor-beta receptor (TGF-βR) deletion and compromised T-cell-mediated tumor rejection. Although Smad4 was dispensable for T cell generation, homeostasis, and effector function, it was essential for T cell proliferation after activation in vitro and in vivo. The transcription factor Myc was identified to mediate Smad4-controlled T cell proliferation. This study thus reveals a requirement of Smad4 for T-cell-mediated autoimmunity and tumor rejection, which is beyond the current paradigm. It highlights a TGF-βR-independent role for Smad4 in promoting T cell function, autoimmunity, and anti-tumor immunity. Copyright © 2015 Elsevier Inc. All rights reserved.

Reprogramming of Pancreatic Exocrine Cells AR42J Into Insulin-producing Cells Using mRNAs for Pdx1, Ngn3, and MafA Transcription Factors.

PubMed

Koblas, Tomas; Leontovyc, Ivan; Loukotova, Sarka; Kosinova, Lucie; Saudek, Frantisek

2016-05-17

Direct reprogramming of pancreatic nonendocrine cells into insulin-producing β-cells represents a promising approach for the treatment of insulin-dependent diabetes. However, its clinical application is limited by the potential for insertional mutagenesis associated with the viral vectors currently used for cell reprogramming. With the aim of developing a nonintegrative reprogramming strategy for derivation of insulin-producing cells, here, we evaluated a new approach utilizing synthetic messenger RNAs encoding reprogramming transcription factors. Administration of synthetic mRNAs encoding three key transcription regulators of β-cell differentiation-Pdx1, Neurogenin3, and MafA-efficiently reprogrammed the pancreatic exocrine cells into insulin-producing cells. In addition to the insulin genes expression, the synthetic mRNAs also induced the expressions of genes important for proper pancreatic β-cell function, including Sur1, Kir6.2, Pcsk1, and Pcsk2. Pretreating cells with the chromatin-modifying agent 5-Aza-2'-deoxycytidine further enhanced reprogramming efficiency, increasing the proportion of insulin-producing cells from 3.5 ± 0.9 to 14.3 ± 1.9% (n = 4). Moreover, 5-Aza-2'-deoxycytidine pretreatment enabled the reprogrammed cells to respond to glucose challenge with increased insulin secretion. In conclusion, our results support that the reprogramming of pancreatic exocrine cells into insulin-producing cells, induced by synthetic mRNAs encoding pancreatic transcription factors, represents a promising approach for cell-based diabetes therapy.

Appearance of cell-adhesion factor in osteoblast proliferation and differentiation of apatite coating titanium by blast coating method.

PubMed

Umeda, Hirotsugu; Mano, Takamitsu; Harada, Koji; Tarannum, Ferdous; Ueyama, Yoshiya

2017-08-01

We have already reported that the apatite coating of titanium by the blast coating (BC) method could show a higher rate of bone contact from the early stages in vivo, when compared to the pure titanium (Ti) and the apatite coating of titanium by the flame spraying (FS) method. However, the detailed mechanism by which BC resulted in satisfactory bone contact is still unknown. In the present study, we investigated the importance of various factors including cell adhesion factor in osteoblast proliferation and differentiation that could affect the osteoconductivity of the BC disks. Cell proliferation assay revealed that Saos-2 could grow fastest on BC disks, and that a spectrophotometric method using a LabAssay TM ALP kit showed that ALP activity was increased in cells on BC disks compared to Ti disks and FS disks. In addition, higher expression of E-cadherin and Fibronectin was observed in cells on BC disks than Ti disks and FS disks by relative qPCR as well as Western blotting. These results suggested that the expression of cell-adhesion factors, proliferation and differentiation of osteoblast might be enhanced on BC disks, which might result higher osteoconductivity.

Induction of muscle stem cell quiescence by the secreted niche factor Oncostatin M.

PubMed

Sampath, Srinath C; Sampath, Srihari C; Ho, Andrew T V; Corbel, Stéphane Y; Millstone, Joshua D; Lamb, John; Walker, John; Kinzel, Bernd; Schmedt, Christian; Blau, Helen M

2018-04-18

The balance between stem cell quiescence and proliferation in skeletal muscle is tightly controlled, but perturbed in a variety of disease states. Despite progress in identifying activators of stem cell proliferation, the niche factor(s) responsible for quiescence induction remain unclear. Here we report an in vivo imaging-based screen which identifies Oncostatin M (OSM), a member of the interleukin-6 family of cytokines, as a potent inducer of muscle stem cell (MuSC, satellite cell) quiescence. OSM is produced by muscle fibers, induces reversible MuSC cell cycle exit, and maintains stem cell regenerative capacity as judged by serial transplantation. Conditional OSM receptor deletion in satellite cells leads to stem cell depletion and impaired regeneration following injury. These results identify Oncostatin M as a secreted niche factor responsible for quiescence induction, and for the first time establish a direct connection between induction of quiescence, stemness, and transplantation potential in solid organ stem cells.

Epidermal growth factor increases LRF/Pokemon expression in human prostate cancer cells.

PubMed

Aggarwal, Himanshu; Aggarwal, Anshu; Agrawal, Devendra K

2011-10-01

Leukemia/lymphoma related factor/POK erythroid myeloid ontogenic factor (LRF/Pokemon) is a member of the POK family of proteins that promotes oncogenesis in several forms of cancer. Recently, we found higher LRF expression in human breast and prostate carcinomas compared to the corresponding normal tissues. The aim of this study was to examine the regulation of LRF expression in human prostate cells. Epidermal growth factor (EGF) and its receptors mediate several tumorigenic cascades that regulate cell differentiation, proliferation, migration and survival of prostate cancer cells. There was significantly higher level of LRF expression in the nucleus of LNCaP and PC-3 cells than RWPE-1 cells. A significant increase in LRF expression was observed with increasing doses of EGF in more aggressive and androgen-sensitive prostate cancer cells suggesting that EGF signaling pathway is critical in upregulating the expression of LRF/Pokemon to promote oncogenesis. Copyright © 2011 Elsevier Inc. All rights reserved.

Dye laser amplifier including a dye cell contained within a support vessel

DOEpatents

Davin, James

1992-01-01

A large (high flow rate) dye laser amplifier in which a continous replenished supply of dye is excited by a first light beam, specifically a copper vapor laser beam, in order to amplify the intensity of a second different light beam, specifically a dye beam, passing through the dye is disclosed herein. This amplifier includes a dye cell defining a dye chamber through which a continuous stream of dye is caused to pass at a flow rate of greater than 30 gallons/minute at a static pressure greater than 150 pounds/square inch and a specifically designed support vessel for containing the dye cell.

c-Met in esophageal squamous cell carcinoma: an independent prognostic factor and potential therapeutic target.

PubMed

Ozawa, Yohei; Nakamura, Yasuhiro; Fujishima, Fumiyoshi; Felizola, Saulo J A; Takeda, Kenichiro; Okamoto, Hiroshi; Ito, Ken; Ishida, Hirotaka; Konno, Takuro; Kamei, Takashi; Miyata, Go; Ohuchi, Noriaki; Sasano, Hironobu

2015-06-03

c-Met is widely known as a poor prognostic factor in various human malignancies. Previous studies have suggested the involvement of c-Met and/or its ligand, hepatocyte growth factor (HGF), in esophageal squamous cell carcinoma (ESCC), but the correlation between c-Met status and clinical outcome remains unclear. Furthermore, the identification of a novel molecular therapeutic target might potentially help improve the clinical outcome of ESCC patients. The expression of c-Met and HGF was immunohistochemically assessed in 104 surgically obtained tissue specimens. The correlation between c-Met/HGF expression and patients' clinicopathological features, including survival, was evaluated. We also investigated changes in cell functions and protein expression of c-Met and its downstream signaling pathway components under treatments with HGF and/or c-Met inhibitor in ESCC cell lines. Elevated expression of c-Met was significantly correlated with tumor depth and pathological stage. Patients with high c-Met expression had significantly worse survival. In addition, multivariate analysis identified the high expression of c-Met as an independent prognostic factor. Treatment with c-Met inhibitor under HGF stimulation significantly inhibited the invasive capacity of an ESCC cell line with elevated c-Met mRNA expression. Moreover, c-Met and its downstream signaling inactivation was also detected after treatment with c-Met inhibitor. The results of our study identified c-Met expression as an independent prognostic factor in ESCC patients and demonstrated that c-Met could be a potential molecular therapeutic target for the treatment of ESCC with elevated c-Met expression.

Transforming Growth Factor-β Drives the Transendothelial Migration of Hepatocellular Carcinoma Cells

PubMed Central

Koudelkova, Petra; Costina, Victor; Weber, Gerhard; Dooley, Steven; Findeisen, Peter; Winter, Peter; Agarwal, Rahul; Schlangen, Karin

2017-01-01

The entry of malignant hepatocytes into blood vessels is a key step in the dissemination and metastasis of hepatocellular carcinoma (HCC). The identification of molecular mechanisms involved in the transmigration of malignant hepatocytes through the endothelial barrier is of high relevance for therapeutic intervention and metastasis prevention. In this study, we employed a model of hepatocellular transmigration that mimics vascular invasion using hepatic sinusoidal endothelial cells and malignant hepatocytes evincing a mesenchymal-like, invasive phenotype by transforming growth factor (TGF)-β. Labelling of respective cell populations with various stable isotopes and subsequent mass spectrometry analyses allowed the “real-time” detection of molecular changes in both transmigrating hepatocytes and endothelial cells. Interestingly, the proteome profiling revealed 36 and 559 regulated proteins in hepatocytes and endothelial cells, respectively, indicating significant changes during active transmigration that mostly depends on cell–cell interaction rather than on TGF-β alone. Importantly, matching these in vitro findings with HCC patient data revealed a panel of common molecular alterations including peroxiredoxin-3, epoxide hydrolase, transgelin-2 and collectin 12 that are clinically relevant for the patient’s survival. We conclude that hepatocellular plasticity induced by TGF-β is crucially involved in blood vessel invasion of HCC cells. PMID:28994702

Induction of autocrine factor inhibiting cell motility from murine B16-BL6 melanoma cells by alpha-melanocyte stimulating hormone.

PubMed

Murata, J; Ayukawa, K; Ogasawara, M; Watanabe, H; Saiki, I

1999-03-15

We have previously reported that neuropeptide alpha-melanocyte stimulating hormone (alpha-MSH) successfully inhibited Matrigel invasion and haptotactic migration of B16-BL6 melanoma cells towards both fibronectin and laminin without affecting their growth. In the present study, we investigated the inhibitory mechanism of tumor cell motility by alpha-MSH. Alpha-MSH significantly blocked the autocrine motility factor (AMF)-enhanced cell motility. However, alpha-MSH did neither prevent the secretion of AMF from B16-BL6 cells nor alter the expression level of AMF receptor (gp78). On the other hand, alpha-MSH induced the secretion of the motility inhibitory factor(s) from B16-BL6 cells in a concentration- and time-dependent manner. The induction of the motility inhibitor(s) was proportional to increasing levels of intracellular cAMP induced by alpha-MSH as well as forskolin, and the activity was abolished by an adenylate cyclase inhibitor, 2',5'-dideoxyadenosine (DDA). The motility-inhibiting activity in conditioned medium (CM) from alpha-MSH-treated B16-BL6 cells was found to have a m.w. below 3 kDa after fractionation. This activity was abolished by boiling but insensitive to trypsin. The treatment of tumor cells with cycloheximide reduced the activity in alpha-MSH-stimulated CM. Our results suggest that alpha-MSH inhibited the motility of B16-BL6 cells through induction of autocrine factor(s).

Non-coding Double-stranded RNA and Antimicrobial Peptide LL-37 Induce Growth Factor Expression from Keratinocytes and Endothelial Cells*

PubMed Central

Adase, Christopher A.; Borkowski, Andrew W.; Zhang, Ling-juan; Williams, Michael R.; Sato, Emi; Sanford, James A.

2016-01-01

A critical function for skin is that when damaged it must simultaneously identify the nature of the injury, repair barrier function, and limit the intrusion of pathogenic organisms. These needs are carried out through the detection of damage-associated molecular patterns (DAMPs) and a response that includes secretion of cytokines, chemokines, growth factors, and antimicrobial peptides (AMPs). In this study, we analyzed how non-coding double-stranded RNA (dsRNAs) act as a DAMP in the skin and how the human cathelicidin AMP LL-37 might influence growth factor production in response to this DAMP. dsRNA alone significantly increased the expression of multiple growth factors in keratinocytes, endothelial cells, and fibroblasts. Furthermore, RNA sequencing transcriptome analysis found that multiple growth factors increase when cells are exposed to both LL-37 and dsRNA, a condition that mimics normal wounding. Quantitative PCR and/or ELISA validated that growth factors expressed by keratinocytes in these conditions included, but were not limited to, basic fibroblast growth factor (FGF2), heparin-binding EGF-like growth factor (HBEGF), vascular endothelial growth factor C (VEGFC), betacellulin (BTC), EGF, epiregulin (EREG), and other members of the transforming growth factor β superfamily. These results identify a novel role for DAMPs and AMPs in the stimulation of repair and highlight the complex interactions involved in the wound environment. PMID:27048655

Growth factor-induced morphological, physiological and molecular characteristics in cerebral endothelial cells.

PubMed

Krizbai, I A; Bauer, H; Amberger, A; Hennig, B; Szabó, H; Fuchs, R; Bauer, H C

2000-09-01

The capacity of vascular endothelial cells to modulate their phenotype in response to changes in environmental conditions is one of the most important characteristics of this cell type. Since different growth factors may play an important signalling role in this adaptive process we have investigated the effect of endothelial cell growth factor (ECGF) on morphological, physiological and molecular characteristics of cerebral endothelial cells (CECs). CECs grown in the presence of ECGF and its cofactor heparin exhibit an epithelial-like morphology (type I CECs). Upon removal of growth factors, CECs develop an elongated spindle-like shape (type II CECs) which is accompanied by the reorganization of actin filaments and the induction of alpha-actin expression. Since one of the most important functions of CECs is the creation of a selective diffusion barrier between the blood and the central nervous system (CNS), we have studied the expression of junction-related proteins in both cell types. We have found that removal of growth factors from endothelial cultures leads to the downregulation of cadherin and occludin protein levels. The loss of junctional proteins was accompanied by a significant increase in the migratory activity and an altered protease activity profile of the cells. TGF-beta1 suppressed endothelial migration in all experiments. Our data provide evidence to suggest that particular endothelial functions are largely controlled by the presence of growth factors. The differences in adhesiveness and migration may play a role in important physiological and pathological processes of endothelial cells such as vasculogenesis or tumor progression.

Sublytic complement protects prostate cancer cells from tumour necrosis factor-α-induced cell death.

PubMed

Liu, L; Li, W; Li, Z; Kirschfink, M

2012-08-01

Inflammation is a critical component of tumour progression. Although complement and tumour necrosis factor (TNF)-α potentially exert significant anti-tumour effects, both mediators may also promote tumour progression. It has been demonstrated that sublytic complement confers resistance on tumour cells not only against lytic complement, but also other danger molecules such as perforin. In low concentrations, TNF promotes survival of malignant cells rather than exerting cytotoxic activity. In this study, we tested if sublytic complement is able to interfere with TNF-mediated tumour cell killing. Our results demonstrate that either subcytotoxic concentrations of TNF or sublytic complement rescue prostate carcinoma cells (DU145) from TNF-α-mediated cell death. Upon pretreatment with low-dose TNF-α, but not upon pre-exposure to sublytic complement, TNF resistance was associated with the down-regulation of TNF receptor 1 (TNF-R1) expression. Complement-induced protection against TNF-mediated apoptosis accompanied the induction of anti-apoptotic proteins [B cell leukaemia/lymphoma (Bcl)-2 and Bcl-xL] at an early stage followed by inhibition of the TNF-induced decrease in the amount of Bcl-2 and Bcl-xL. Cell protection also accompanied the inhibition of caspase-8 activation, poly (ADP-ribose) polymerase (PARP)-1 cleavage and the activation of nuclear factor (NF)-κB. Our data extend our current view on the induction of tumour cell resistance against cytotoxic mediators supporting the role of the tumour microenvironment in mediating protection against the anti-cancer immune response. © 2012 The Authors. Clinical and Experimental Immunology © 2012 British Society for Immunology.

Regulation of tissue factor in NT2 germ cell tumor cells by cisplatin chemotherapy.

PubMed

Jacobsen, Christine; Oechsle, Karin; Hauschild, Jessica; Steinemann, Gustav; Spath, Brigitte; Bokemeyer, Carsten; Ruf, Wolfram; Honecker, Friedemann; Langer, Florian

2015-09-01

Patients with germ cell tumors (GCTs) receiving cisplatin-based chemotherapy are at increased risk of thrombosis, but the underlying cellular and molecular mechanisms remain obscure. To study baseline tissue factor (TF) expression by GCT cell lines and its modulation by cisplatin treatment. TF expression was assessed by single-stage clotting and thrombin generation assay, flow cytometry, ELISA, and Western blot analysis. Cell cycle analysis and detection of phosphatidylserine (PS) membrane exposure were carried out by flow cytometry. TF mRNA was analyzed by quantitative RT-PCR. Significant expression of TF-specific procoagulant activity (PCA) was detected on three non-seminoma (NT2, 2102Ep, NCCIT) and one seminoma cell line (TCam-2). Treatment with 0.4μM cisplatin (corresponding to the IC50) for 48hrs increased TF PCA on NT2 cells 3-fold, an effect that was largely independent of PS exposure and that could not be explained by translocation of active TF from intracellular storage pools. Cisplatin-induced TF PCA expression in NT2 cells did not occur before 12hrs, but was steady thereafter and accompanied by a 2-fold increase in total and surface-located TF antigen. Importantly, increased TF gene transcription or production and release of an intermediate factor were not involved in this process. Cell cycle analysis suggested that cisplatin-induced G2/M arrest resulted in an accumulation of procoagulant TF on the membrane surface of NT2 cells. In addition to induction of apoptosis/necrosis with PS-mediated activation of preformed TF, cisplatin may alter the procoagulant phenotype of GCT cells through an increase in total cellular TF antigen. Copyright © 2015 Elsevier Ltd. All rights reserved.

C3 exoenzyme impairs cell proliferation and apoptosis by altering the activity of transcription factors.

PubMed

von Elsner, Leonie; Hagemann, Sandra; Just, Ingo; Rohrbeck, Astrid

2016-09-01

C3 exoenzyme from C. botulinum is an ADP-ribosyltransferase that inactivates selectively RhoA, B, and C by coupling an ADP-ribose moiety. Rho-GTPases are involved in various cellular processes, such as regulation of actin cytoskeleton, cell proliferation, and apoptosis. Previous studies of our group with the murine hippocampal cell line HT22 revealed a C3-mediated inhibition of cell proliferation after 48 h and a prevention of serum-starved cells from apoptosis. For both effects, alterations of various signaling pathways are already known, including also changes on the transcriptional level. Investigations on the transcriptional activity in HT22 cells treated with C3 for 48 h identified five out of 48 transcription factors namely Sp1, ATF2, E2F-1, CBF, and Stat6 with a significantly regulated activity. For validation of identified transcription factors, studies on the protein level of certain target genes were performed. Western blot analyses exhibited an enhanced abundance of Sp1 target genes p21 and COX-2 as well as an increase in phosphorylation of c-Jun. In contrast, the level of p53 and apoptosis-inducing GADD153, a target gene of ATF2, was decreased. Our results reveal that C3 regulates the transcriptional activity of Sp1 and ATF2 resulting downstream in an altered protein abundance of various target genes. As the affected proteins are involved in the regulation of cell proliferation and apoptosis, thus the C3-mediated anti-proliferative and anti-apoptotic effects are consequences of the Rho-dependent alterations of the activity of certain transcriptional factors.

T-Cell response profiling to biological threat agents including the SARS coronavirus.

PubMed

Gioia, C; Horejsh, D; Agrati, C; Martini, F; Capobianchi, M R; Ippolito, G; Poccia, F

2005-01-01

The emergence of pathogens such as SARS and the increased threat of bioterrorism has stimulated the development of novel diagnostic assays for differential diagnosis. Rather than focusing on the detection of an individual pathogen component, we have developed a T cell profiling system to monitor responses to the pathogens in an array format. Using a matrix of antigens specific for different pathogens, a specific T cell profile was generated for each individual by monitoring the intracellular production of interferon-gamma by flow cytometry. This assay allows for the testing of multiple proteins or peptides at a single time and provides a quantitative and phenotypic assessment of CD4(+) and CD8(+) responding cells. We present profiling examples for several positive individuals, including those vaccinated with the smallpox and anthrax vaccines. We also show antigen optimization for the SARS-hCoV, as studies revealed that these proteins contain peptides which cross-react with more common coronaviruses, a cause of the common cold. The T cell array is an early and sensitive multiplex measure of active infection, exposure to a pathogen, or effective, recent vaccination.

Microparticles released by vascular endothelial cells increase hypoxia inducible factor expression in human proximal tubular HK-2 cells.

PubMed

Fernandez-Martínez, Ana Belen; Torija, Ana Valdehita; Carracedo, Julia; Ramirez, Rafael; de Lucio-Cazaña, Francisco Javier

2014-08-01

Microparticles are produced by vesiculation of the cell plasma membrane and serve as vectors of cell-to-cell communication. Co-culture experiments have shown that hypoxia-inducible factor-α (HIF-α)-regulated-genes are up-regulated in human renal proximal tubular HK-2 cells by endothelial cell factors which might be transported inside endothelial microparticles (EMP). Here we aimed to study in HK-2 cells the effect of EMP, produced by activated endothelial cells, on HIF-α and HIF-α-regulated vascular endothelial growth factor-A (VEGF-A). EMP, at a concentration much lower than that found in plasma, increased the expression of HIF-α/VEGF-A in a COX-2/EP2 receptor dependent manner. Since the EMP/cells ratio was ∼1/1000, we hypothesized that paracrine mediators produced by HK-2 cells amplified the initial signal. This hypothesis was confirmed by two facts which also suggested that the mediators were conveyed by particles released by HK-2 cells: (i) HIF-α was up-regulated in HK-2 cells treated with the pellet obtained from the conditioned medium of the EMP-treated HK-2 cells. (ii) In transwell experiments, EMP-treated cells increased the expression of HIF-α in untreated HK-2 cells. Interestingly, we detected these cells, particles that were released by EMP-treated HK-2 cells. Depending on the pathological context, activation of HIF-α and VEGF-A signaling in renal tissue/cells may have either beneficial or harmful effects. Therefore, our results suggest that their presence in the urinary space of EMP produced by activated endothelial cells may influence the outcome of a number of renal diseases. Copyright © 2014 Elsevier Ltd. All rights reserved.

Airway Delivery of Soluble Factors from Plastic-Adherent Bone Marrow Cells Prevents Murine Asthma

PubMed Central

Ionescu, Lavinia I.; Alphonse, Rajesh S.; Arizmendi, Narcy; Morgan, Beverly; Abel, Melanie; Eaton, Farah; Duszyk, Marek; Vliagoftis, Harissios; Aprahamian, Tamar R.; Walsh, Kenneth

2012-01-01

Asthma affects an estimated 300 million people worldwide and accounts for 1 of 250 deaths and 15 million disability-adjusted life years lost annually. Plastic-adherent bone marrow–derived cell (BMC) administration holds therapeutic promise in regenerative medicine. However, given the low cell engraftment in target organs, including the lung, cell replacement cannot solely account for the reported therapeutic benefits. This suggests that BMCs may act by secreting soluble factors. BMCs also possess antiinflammatory and immunomodulatory properties and may therefore be beneficial for asthma. Our objective was to investigate the therapeutic potential of BMC-secreted factors in murine asthma. In a model of acute and chronic asthma, intranasal instillation of BMC conditioned medium (CdM) prevented airway hyperresponsiveness (AHR) and inflammation. In the chronic asthma model, CdM prevented airway smooth muscle thickening and peribronchial inflammation while restoring blunted salbutamol-induced bronchodilation. CdM reduced lung levels of the TH2 inflammatory cytokines IL-4 and IL-13 and increased levels of IL-10. CdM up-regulated an IL-10–induced and IL-10–secreting subset of T regulatory lymphocytes and promoted IL-10 expression by lung macrophages. Adiponectin (APN), an antiinflammatory adipokine found in CdM, prevented AHR, airway smooth muscle thickening, and peribronchial inflammation, whereas the effect of CdM in which APN was neutralized or from APN knock-out mice was attenuated compared with wild-type CdM. Our study provides evidence that BMC-derived soluble factors prevent murine asthma and suggests APN as one of the protective factors. Further identification of BMC-derived factors may hold promise for novel approaches in the treatment of asthma. PMID:21903873

Airway delivery of soluble factors from plastic-adherent bone marrow cells prevents murine asthma.

PubMed

Ionescu, Lavinia I; Alphonse, Rajesh S; Arizmendi, Narcy; Morgan, Beverly; Abel, Melanie; Eaton, Farah; Duszyk, Marek; Vliagoftis, Harissios; Aprahamian, Tamar R; Walsh, Kenneth; Thébaud, Bernard

2012-02-01

Asthma affects an estimated 300 million people worldwide and accounts for 1 of 250 deaths and 15 million disability-adjusted life years lost annually. Plastic-adherent bone marrow-derived cell (BMC) administration holds therapeutic promise in regenerative medicine. However, given the low cell engraftment in target organs, including the lung, cell replacement cannot solely account for the reported therapeutic benefits. This suggests that BMCs may act by secreting soluble factors. BMCs also possess antiinflammatory and immunomodulatory properties and may therefore be beneficial for asthma. Our objective was to investigate the therapeutic potential of BMC-secreted factors in murine asthma. In a model of acute and chronic asthma, intranasal instillation of BMC conditioned medium (CdM) prevented airway hyperresponsiveness (AHR) and inflammation. In the chronic asthma model, CdM prevented airway smooth muscle thickening and peribronchial inflammation while restoring blunted salbutamol-induced bronchodilation. CdM reduced lung levels of the T(H)2 inflammatory cytokines IL-4 and IL-13 and increased levels of IL-10. CdM up-regulated an IL-10-induced and IL-10-secreting subset of T regulatory lymphocytes and promoted IL-10 expression by lung macrophages. Adiponectin (APN), an antiinflammatory adipokine found in CdM, prevented AHR, airway smooth muscle thickening, and peribronchial inflammation, whereas the effect of CdM in which APN was neutralized or from APN knock-out mice was attenuated compared with wild-type CdM. Our study provides evidence that BMC-derived soluble factors prevent murine asthma and suggests APN as one of the protective factors. Further identification of BMC-derived factors may hold promise for novel approaches in the treatment of asthma.

c-Met and its ligand hepatocyte growth factor/scatter factor regulate mature B cell survival in a pathway induced by CD74.

PubMed

Gordin, Maya; Tesio, Melania; Cohen, Sivan; Gore, Yael; Lantner, Frida; Leng, Lin; Bucala, Richard; Shachar, Idit

2010-08-15

The signals regulating the survival of mature splenic B cells have become a major focus in recent studies of B cell immunology. Durable B cell persistence in the periphery is dependent on survival signals that are transduced by cell surface receptors. In this study, we describe a novel biological mechanism involved in mature B cell homeostasis, the hepatocyte growth factor/scatter factor (HGF)/c-Met pathway. We demonstrate that c-Met activation by HGF leads to a survival cascade, whereas its blockade results in induction of mature B cell death. Our results emphasize a unique and critical function for c-Met signaling in the previously described macrophage migration inhibitory factor/CD74-induced survival pathway. Macrophage migration inhibitory factor recruits c-Met to the CD74/CD44 complex and thereby enables the induction of a signaling cascade within the cell. This signal results in HGF secretion, which stimulates the survival of the mature B cell population in an autocrine manner. Thus, the CD74-HGF/c-Met axis defines a novel physiologic survival pathway in mature B cells, resulting in the control of the humoral immune response.

A Pdx-1-Regulated Soluble Factor Activates Rat and Human Islet Cell Proliferation

PubMed Central

Hayes, Heather L.; Zhang, Lu; Becker, Thomas C.; Haldeman, Jonathan M.; Stephens, Samuel B.; Arlotto, Michelle; Moss, Larry G.; Newgard, Christopher B.

2016-01-01

The homeodomain transcription factor Pdx-1 has important roles in pancreas and islet development as well as in β-cell function and survival. We previously reported that Pdx-1 overexpression stimulates islet cell proliferation, but the mechanism remains unclear. Here, we demonstrate that overexpression of Pdx-1 triggers proliferation largely by a non-cell-autonomous mechanism mediated by soluble factors. Consistent with this idea, overexpression of Pdx-1 under the control of a β-cell-specific promoter (rat insulin promoter [RIP]) stimulates proliferation of both α and β cells, and overexpression of Pdx-1 in islets separated by a Transwell membrane from islets lacking Pdx-1 overexpression activates proliferation in the untreated islets. Microarray and gene ontology (GO) analysis identified inhibin beta-B (Inhbb), an activin subunit and member of the transforming growth factor β (TGF-β) superfamily, as a Pdx-1-responsive gene. Overexpression of Inhbb or addition of activin B stimulates rat islet cell and β-cell proliferation, and the activin receptors RIIA and RIIB are required for the full proliferative effects of Pdx-1 in rat islets. In human islets, Inhbb overexpression stimulates total islet cell proliferation and potentiates Pdx-1-stimulated proliferation of total islet cells and β cells. In sum, this study identifies a mechanism by which Pdx-1 induces a soluble factor that is sufficient to stimulate both rat and human islet cell proliferation. PMID:27620967

Complement Regulator Factor H Mediates a Two-step Uptake of Streptococcus pneumoniae by Human Cells*

PubMed Central

Agarwal, Vaibhav; Asmat, Tauseef M.; Luo, Shanshan; Jensch, Inga; Zipfel, Peter F.; Hammerschmidt, Sven

2010-01-01

Streptococcus pneumoniae, a human pathogen, recruits complement regulator factor H to its bacterial cell surface. The bacterial PspC protein binds Factor H via short consensus repeats (SCR) 8–11 and SCR19–20. In this study, we define how bacterially bound Factor H promotes pneumococcal adherence to and uptake by epithelial cells or human polymorphonuclear leukocytes (PMNs) via a two-step process. First, pneumococcal adherence to epithelial cells was significantly reduced by heparin and dermatan sulfate. However, none of the glycosaminoglycans affected binding of Factor H to pneumococci. Adherence of pneumococci to human epithelial cells was inhibited by monoclonal antibodies recognizing SCR19–20 of Factor H suggesting that the C-terminal glycosaminoglycan-binding region of Factor H mediates the contact between pneumococci and human cells. Blocking of the integrin CR3 receptor, i.e. CD11b and CD18, of PMNs or CR3-expressing epithelial cells reduced significantly the interaction of pneumococci with both cell types. Similarly, an additional CR3 ligand, Pra1, derived from Candida albicans, blocked the interaction of pneumococci with PMNs. Strikingly, Pra1 inhibited also pneumococcal uptake by lung epithelial cells but not adherence. In addition, invasion of Factor H-coated pneumococci required the dynamics of host-cell actin microfilaments and was affected by inhibitors of protein-tyrosine kinases and phosphatidylinositol 3-kinase. In conclusion, pneumococcal entry into host cells via Factor H is based on a two-step mechanism. The first and initial contact of Factor H-coated pneumococci is mediated by glycosaminoglycans expressed on the surface of human cells, and the second step, pneumococcal uptake, is integrin-mediated and depends on host signaling molecules such as phosphatidylinositol 3-kinase. PMID:20504767

A&M. TAN607. Special service cubicle (hot cell). Details include Zpipe ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

A&M. TAN-607. Special service cubicle (hot cell). Details include Z-pipe and stepped plug penetrations through shielding wall. Ralph M. Parsons 902-3-ANP-607-A116. Date: December 1952. Approved by INEEL Classification Office for public release. INEEL index code no. 034-0607-693-106767 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

Hepatocyte growth factor limits autoimmune neuroinflammation via glucocorticoid-induced leucine zipper expression in dendritic cells.

PubMed

Benkhoucha, Mahdia; Molnarfi, Nicolas; Dunand-Sauthier, Isabelle; Merkler, Doron; Schneiter, Gregory; Bruscoli, Stefano; Riccardi, Carlo; Tabata, Yasuhiko; Funakoshi, Hiroshi; Nakamura, Toshikazu; Reith, Walter; Santiago-Raber, Marie-Laure; Lalive, Patrice H

2014-09-15

Autoimmune neuroinflammation, including multiple sclerosis and its animal model, experimental autoimmune encephalomyelitis (EAE), a prototype for T cell-mediated autoimmunity, is believed to result from immune tolerance dysfunction leading to demyelination and substantial neurodegeneration. We previously showed that CNS-restricted expression of hepatocyte growth factor (HGF), a potent neuroprotective factor, reduced CNS inflammation and clinical deficits associated with EAE. In this study, we demonstrate that systemic HGF treatment ameliorates EAE through the development of tolerogenic dendritic cells (DCs) with high expression levels of glucocorticoid-induced leucine zipper (GILZ), a transcriptional repressor of gene expression and a key endogenous regulator of the inflammatory response. RNA interference-directed neutralization of GILZ expression by DCs suppressed the induction of tolerance caused by HGF. Finally, adoptive transfer of HGF-treated DCs from wild-type but not GILZ gene-deficient mice potently mediated functional recovery in recipient mice with established EAE through effective modulation of autoaggressive T cell responses. Altogether, these results show that by inducing GILZ in DCs, HGF reproduces the mechanism of immune regulation induced by potent immunomodulatory factors such as IL-10, TGF-β1, and glucocorticoids and therefore that HGF therapy may have potential in the treatment of autoimmune dysfunctions. Copyright © 2014 by The American Association of Immunologists, Inc.

Trypsinogen 4 boosts tumor endothelial cells migration through proteolysis of tissue factor pathway inhibitor-2.

PubMed

Ghilardi, Carmen; Silini, Antonietta; Figini, Sara; Anastasia, Alessia; Lupi, Monica; Fruscio, Robert; Giavazzi, Raffaella; Bani, Maria Rosa

2015-09-29

Proteases contribute to cancer in many ways, including tumor vascularization and metastasis, and their pharmacological inhibition is a potential anticancer strategy. We report that human endothelial cells (EC) express the trypsinogen 4 isoform of the serine protease 3 (PRSS3), and lack both PRSS2 and PRSS1. Trypsinogen 4 expression was upregulated by the combined action of VEGF-A, FGF-2 and EGF, angiogenic factors representative of the tumor microenvironment. Suppression of trypsinogen 4 expression by siRNA inhibited the angiogenic milieu-induced migration of EC from cancer specimens (tumor-EC), but did not affect EC from normal tissues. We identified tissue factor pathway inhibitor-2 (TFPI-2), a matrix associated inhibitor of cell motility, as the functional target of trypsinogen 4, which cleaved TFPI-2 and removed it from the matrix put down by tumor-EC. Silencing tumor-EC for trypsinogen 4 accumulated TFPI2 in the matrix. Showing that angiogenic factors stimulate trypsinogen 4 expression, which hydrolyses TFPI-2 favoring a pro-migratory situation, our study suggests a new pathway linking tumor microenvironment signals to endothelial cell migration, which is essential for angiogenesis and blood vessel remodeling. Abolishing trypsinogen 4 functions might be an exploitable strategy as anticancer, particularly anti-vascular, therapy.

Trypsinogen 4 boosts tumor endothelial cells migration through proteolysis of tissue factor pathway inhibitor-2

PubMed Central

Ghilardi, Carmen; Silini, Antonietta; Figini, Sara; Anastasia, Alessia; Lupi, Monica; Fruscio, Robert; Giavazzi, Raffaella; Bani, MariaRosa

2015-01-01

Proteasescontribute to cancer in many ways, including tumor vascularization and metastasis, and their pharmacological inhibition is a potential anticancer strategy. We report that human endothelial cells (EC) express the trypsinogen 4 isoform of the serine protease 3 (PRSS3), and lack both PRSS2 and PRSS1. Trypsinogen 4 expression was upregulated by the combined action of VEGF-A, FGF-2 and EGF, angiogenic factors representative of the tumor microenvironment. Suppression of trypsinogen 4 expression by siRNA inhibited the angiogenic milieu-induced migration of EC from cancer specimens (tumor-EC), but did not affect EC from normal tissues. We identified tissue factor pathway inhibitor-2 (TFPI-2), a matrix associated inhibitor of cell motility, as the functional target of trypsinogen 4, which cleaved TFPI-2 and removed it from the matrix put down by tumor-EC. Silencing tumor-EC for trypsinogen 4 accumulated TFPI2 in the matrix. Showing that angiogenic factors stimulate trypsinogen 4 expression, which hydrolyses TFPI-2 favoring a pro-migratory situation, our study suggests a new pathway linking tumor microenvironment signals to endothelial cell migration, which is essential for angiogenesis and blood vessel remodeling. Abolishing trypsinogen 4 functions might be an exploitable strategy as anticancer, particularly anti-vascular, therapy. PMID:26318044

A flexible and qualitatively stable model for cell cycle dynamics including DNA damage effects.

PubMed

Jeffries, Clark D; Johnson, Charles R; Zhou, Tong; Simpson, Dennis A; Kaufmann, William K

2012-01-01

This paper includes a conceptual framework for cell cycle modeling into which the experimenter can map observed data and evaluate mechanisms of cell cycle control. The basic model exhibits qualitative stability, meaning that regardless of magnitudes of system parameters its instances are guaranteed to be stable in the sense that all feasible trajectories converge to a certain trajectory. Qualitative stability can also be described by the signs of real parts of eigenvalues of the system matrix. On the biological side, the resulting model can be tuned to approximate experimental data pertaining to human fibroblast cell lines treated with ionizing radiation, with or without disabled DNA damage checkpoints. Together these properties validate a fundamental, first order systems view of cell dynamics. Classification Codes: 15A68.

The cell-penetrating peptide domain from human heparin-binding epidermal growth factor-like growth factor (HB-EGF) has anti-inflammatory activity in vitro and in vivo.

PubMed

Lee, Jue-Yeon; Seo, Yoo-Na; Park, Hyun-Jung; Park, Yoon-Jeong; Chung, Chong-Pyoung

2012-03-23

A heparin-binding peptide (HBP) sequence from human heparin-binding epidermal growth factor-like growth factor (HB-EGF) was identified and was shown to exhibit cell penetration activity. This cell penetration induced an anti-inflammatory reaction in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. HBP penetrated the cell membrane during the 10 min treatment and reduced the LPS-induced production of nitric oxide (NO), inducible nitric oxide synthase (iNOS), and cytokines (TNF-α and IL-6) in a concentration-dependent manner. Additionally, HBP inhibited the LPS-induced upregulation of cytokines, including TNF-α and IL-6, and decreased the interstitial infiltration of polymorphonuclear leukocytes in a lung inflammation model. HBP inhibited NF-κB-dependent inflammatory responses by directly blocking the phosphorylation and degradation of IκBα and by subsequently inhibiting the nuclear translocation of the p65 subunit of NF-κB. Taken together, this novel HBP may be potentially useful candidate for anti-inflammatory treatments and can be combined with other drugs of interest to transport attached molecules into cells. Copyright © 2012 Elsevier Inc. All rights reserved.

Shikonin suppresses proliferation and induces cell cycle arrest through the inhibition of hypoxia-inducible factor-1α signaling.

PubMed

Li, Ming Yue; Mi, Chunliu; Wang, Ke Si; Wang, Zhe; Zuo, Hong Xiang; Piao, Lian Xun; Xu, Guang Hua; Li, Xuezheng; Ma, Juan; Jin, Xuejun

2017-08-25

Hypoxia enhances the development of solid tumors. Hypoxia-inducible factor-1α (HIF-1α) is a transcription factor that is dominantly expressed under hypoxia in solid tumor cells and is a key factor of tumor regulation. HIF-1α regulates several target genes involved in many aspects of cancer progression, including angiogenesis, metastasis, and cell proliferation, as well as imparting resistance to cancer treatment. In this study, we assessed shikonin, which derives from the traditional medical herb Lithospermum erythrorhizon, for its anti-cancer effects in hypoxia-induced human colon cancer cell lines. Shikonin showed potent inhibitory activity against hypoxia-induced HIF-1α activation in various human cancer cell lines and efficient scavenging activity of hypoxia-induced reactive oxygen species in tumor cells. Further analysis revealed that shikonin inhibited HIF-1α protein synthesis without affecting the expression of HIF-1α mRNA or degrading HIF-1α protein. It was subsequently shown to attenuate the activation of downstream mTOR/p70S6K/4E-BP1/eIF4E kinase. Shikonin also dose-dependently caused the cell cycle arrest of activated HCT116 cells and inhibited the proliferation of HCT116 and SW620 cells. Moreover, it significantly inhibited tumor growth in a xenograft modal. These findings suggest that shikonin could be considered for use as a potential drug in human colon cancer therapy. Copyright © 2017 Elsevier B.V. All rights reserved.

Production of Macrophage Inhibitory Factor (MIF) by Primary Sertoli Cells; Its Possible Involvement in Migration of Spermatogonial Cells.

PubMed

Huleihel, Mahmoud; Abofoul-Azab, Maram; Abarbanel, Yael; Einav, Iris; Levitas, Elyahu; Lunenfeld, Eitan

2017-10-01

Macrophage migration inhibitory factor (MIF) is a multifunctional molecule. MIF was originally identified as a T-cell-derived factor responsible for the inhibition of macrophage migration. In testicular tissue of adult rats, MIF is constitutively expressed by Leydig cells under physiological conditions. The aim of this study was to examine MIF levels in testicular homogenates from different aged mice, and the capacity of Sertoli cells to produce it. We also examined MIF involvement in spermatogonial cell migration. Similar levels of MIF protein were detected in testicular homogenates of mice of different ages (1-8-week-old). However, the RNA expression levels of MIF were high in 1-week-old mice and significantly decreased with age compared to 1-week-old mice. MIF was stained in Sertoli, Leydig cells, and developed germ cells in the seminiferous tubules. Isolated Sertoli cells from 1-week-old mice stained to MIF. Cultures of Sertoli cells from 1-week-old mice produced and expressed high levels of MIF which significantly decreased with age. MIF was localized in the cytoplasm and nucleus of Sertoli cell cultures isolated from 1-week-old mice; however, it was localized only in the cytoplasm and branches of cultures isolated from 8-week-old mice. MIFR was detected in GFRα1 and Sertoli cells. MIF could induce migration of spermatogonial cells, and this effect was synergistic with glial cell-line neurotrophic factor. Our results show, for the first time, the capacity of Sertoli cells to produce MIF under normal conditions and that MIFR expressed in GFRα1 and Sertoli cells. We also showed that MIF induced spermatogonial cell migration. J. Cell. Physiol. 232: 2869-2877, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Decoupling the Functional Pleiotropy of Stem Cell Factor by Tuning c-Kit Signaling

PubMed Central

Ho, Chia Chi M.; Chhabra, Akanksha; Starkl, Philipp; Schnorr, Peter-John; Wilmes, Stephan; Moraga, Ignacio; Kwon, Hye-Sook; Gaudenzio, Nicolas; Sibilano, Riccardo; Wehrman, Tom S.; Gakovic, Milica; Sockolosky, Jonathan T.; Tiffany, Matthew R.; Ring, Aaron M.; Piehler, Jacob; Weissman, Irving L.; Galli, Stephen J.; Shizuru, Judith A.; Garcia, K. Christopher

2017-01-01

SUMMARY Most secreted growth factors and cytokines are functionally pleiotropic because their receptors are expressed on diverse cell types. While important for normal mammalian physiology, pleiotropy limits the efficacy of cytokines and growth factors as therapeutics. Stem cell factor (SCF) is a growth factor that acts through the c-Kit receptor tyrosine kinase to elicit hematopoietic progenitor expansion, but can be toxic when administered in vivo because it concurrently activates mast cells. We engineered a mechanism-based SCF partial agonist that impaired c-Kit dimerization, truncating downstream signaling amplitude. This SCF variant elicited biased activation of hematopoietic progenitors over mast cells in vitro and in vivo. Mouse models of SCF-mediated anaphylaxis, radioprotection, and hematopoietic expansion revealed that this SCF partial agonist retained therapeutic efficacy while exhibiting virtually no anaphylactic off-target effects. The approach of biasing cell activation by tuning signaling thresholds and outputs has applications to many dimeric receptor-ligand systems. PMID:28283060

Oxalobacter formigenes–Derived Bioactive Factors Stimulate Oxalate Transport by Intestinal Epithelial Cells

PubMed Central

Arvans, Donna; Jung, Yong-Chul; Antonopoulos, Dionysios; Koval, Jason; Granja, Ignacio; Bashir, Mohamed; Karrar, Eltayeb; Roy-Chowdhury, Jayanta; Musch, Mark; Asplin, John; Chang, Eugene

2017-01-01

Hyperoxaluria is a major risk factor for kidney stones and has no specific therapy, although Oxalobacter formigenes colonization is associated with reduced stone risk. O. formigenes interacts with colonic epithelium and induces colonic oxalate secretion, thereby reducing urinary oxalate excretion, via an unknown secretagogue. The difficulties in sustaining O. formigenes colonization underscore the need to identify the derived factors inducing colonic oxalate secretion. We therefore evaluated the effects of O. formigenes culture conditioned medium (CM) on apical 14C-oxalate uptake by human intestinal Caco-2-BBE cells. Compared with control medium, O. formigenes CM significantly stimulated oxalate uptake (>2.4-fold), whereas CM from Lactobacillus acidophilus did not. Treating the O. formigenes CM with heat or pepsin completely abolished this bioactivity, and selective ultrafiltration of the CM revealed that the O. formigenes–derived factors have molecular masses of 10–30 kDa. Treatment with the protein kinase A inhibitor H89 or the anion exchange inhibitor 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid completely blocked the CM-induced oxalate transport. Knockdown of the oxalate transporter SLC26A6 also significantly restricted the induction of oxalate transport by CM. In a mouse model of primary hyperoxaluria type 1, rectal administration of O. formigenes CM significantly reduced (>32.5%) urinary oxalate excretion and stimulated (>42%) distal colonic oxalate secretion. We conclude that O. formigenes–derived bioactive factors stimulate oxalate transport in intestinal cells through mechanisms including PKA activation. The reduction in urinary oxalate excretion in hyperoxaluric mice treated with O. formigenes CM reflects the in vivo retention of biologic activity and the therapeutic potential of these factors. PMID:27738124

Novel application of stem cell-derived factors for periodontal regeneration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Inukai, Takeharu, E-mail: t-inukai@med.nagoya-u.ac.jp; Katagiri, Wataru, E-mail: w-kat@med.nagoya-u.ac.jp; Yoshimi, Ryoko, E-mail: lianzi@med.nagoya-u.ac.jp

Highlights: Black-Right-Pointing-Pointer Mesenchymal stem cells (MSCs) secrete a variety of cytokines. Black-Right-Pointing-Pointer Cytokines were detected in conditioned medium from cultured MSCs (MSC-CM). Black-Right-Pointing-Pointer MSC-CM enhanced activation of dog MSCs and periodontal ligament cells. Black-Right-Pointing-Pointer MSC-CM significantly promoted alveolar bone and cementum regeneration. Black-Right-Pointing-Pointer Multiple cytokines contained in MSC-CM promote periodontal regeneration. -- Abstract: The effect of conditioned medium from cultured mesenchymal stem cells (MSC-CM) on periodontal regeneration was evaluated. In vitro, MSC-CM stimulated migration and proliferation of dog MSCs (dMSCs) and dog periodontal ligament cells (dPDLCs). Cytokines such as insulin-like growth factor, vascular endothelial growth factor, transforming growth factor-{beta}1, andmore » hepatocyte growth factor were detected in MSC-CM. In vivo, one-wall critical-size, intrabony periodontal defects were surgically created in the mandible of dogs. Dogs with these defects were divided into three groups that received MSC-CM, PBS, or no implants. Absorbable atelo-collagen sponges (TERUPLUG Registered-Sign ) were used as a scaffold material. Based on radiographic and histological observation 4 weeks after transplantation, the defect sites in the MSC-CM group displayed significantly greater alveolar bone and cementum regeneration than the other groups. These findings suggest that MSC-CM enhanced periodontal regeneration due to multiple cytokines contained in MSC-CM.« less

Dynamic Proteomic Analysis of Pancreatic Mesenchyme Reveals Novel Factors That Enhance Human Embryonic Stem Cell to Pancreatic Cell Differentiation.

PubMed

Russ, Holger A; Landsman, Limor; Moss, Christopher L; Higdon, Roger; Greer, Renee L; Kaihara, Kelly; Salamon, Randy; Kolker, Eugene; Hebrok, Matthias

2016-01-01

Current approaches in human embryonic stem cell (hESC) to pancreatic beta cell differentiation have largely been based on knowledge gained from developmental studies of the epithelial pancreas, while the potential roles of other supporting tissue compartments have not been fully explored. One such tissue is the pancreatic mesenchyme that supports epithelial organogenesis throughout embryogenesis. We hypothesized that detailed characterization of the pancreatic mesenchyme might result in the identification of novel factors not used in current differentiation protocols. Supplementing existing hESC differentiation conditions with such factors might create a more comprehensive simulation of normal development in cell culture. To validate our hypothesis, we took advantage of a novel transgenic mouse model to isolate the pancreatic mesenchyme at distinct embryonic and postnatal stages for subsequent proteomic analysis. Refined sample preparation and analysis conditions across four embryonic and prenatal time points resulted in the identification of 21,498 peptides with high-confidence mapping to 1,502 proteins. Expression analysis of pancreata confirmed the presence of three potentially important factors in cell differentiation: Galectin-1 (LGALS1), Neuroplastin (NPTN), and the Laminin α-2 subunit (LAMA2). Two of the three factors (LGALS1 and LAMA2) increased expression of pancreatic progenitor transcript levels in a published hESC to beta cell differentiation protocol. In addition, LAMA2 partially blocks cell culture induced beta cell dedifferentiation. Summarily, we provide evidence that proteomic analysis of supporting tissues such as the pancreatic mesenchyme allows for the identification of potentially important factors guiding hESC to pancreas differentiation.

Dynamic Proteomic Analysis of Pancreatic Mesenchyme Reveals Novel Factors That Enhance Human Embryonic Stem Cell to Pancreatic Cell Differentiation

PubMed Central

Russ, Holger A.; Landsman, Limor; Moss, Christopher L.; Higdon, Roger; Greer, Renee L.; Kaihara, Kelly; Salamon, Randy; Kolker, Eugene; Hebrok, Matthias

2016-01-01

Current approaches in human embryonic stem cell (hESC) to pancreatic beta cell differentiation have largely been based on knowledge gained from developmental studies of the epithelial pancreas, while the potential roles of other supporting tissue compartments have not been fully explored. One such tissue is the pancreatic mesenchyme that supports epithelial organogenesis throughout embryogenesis. We hypothesized that detailed characterization of the pancreatic mesenchyme might result in the identification of novel factors not used in current differentiation protocols. Supplementing existing hESC differentiation conditions with such factors might create a more comprehensive simulation of normal development in cell culture. To validate our hypothesis, we took advantage of a novel transgenic mouse model to isolate the pancreatic mesenchyme at distinct embryonic and postnatal stages for subsequent proteomic analysis. Refined sample preparation and analysis conditions across four embryonic and prenatal time points resulted in the identification of 21,498 peptides with high-confidence mapping to 1,502 proteins. Expression analysis of pancreata confirmed the presence of three potentially important factors in cell differentiation: Galectin-1 (LGALS1), Neuroplastin (NPTN), and the Laminin α-2 subunit (LAMA2). Two of the three factors (LGALS1 and LAMA2) increased expression of pancreatic progenitor transcript levels in a published hESC to beta cell differentiation protocol. In addition, LAMA2 partially blocks cell culture induced beta cell dedifferentiation. Summarily, we provide evidence that proteomic analysis of supporting tissues such as the pancreatic mesenchyme allows for the identification of potentially important factors guiding hESC to pancreas differentiation. PMID:26681951

Complementary deoxyribonucleic acid cloning of spermatogonial stem cell renewal factor.

PubMed

Miura, Takeshi; Ohta, Takashi; Miura, Chiemi I; Yamauchi, Kohei

2003-12-01

Spermatogonial mitosis can be subdivided into two processes: spermatogonial stem cell renewal and spermatogonial proliferation toward meiosis. Recently it has been indicated that estrogen, estradiol-17beta, is involved in regulating the renewal of spermatogonial stem cells in eel. To determine the genes that directly regulate this process, we used expression screening to identify genes whose expression is regulated by estradiol-17beta in testes. We detected a previously unidentified cDNA clone that is up-regulated by estradiol-17beta stimulation and named it eel spermatogenesis-related substances 34 (eSRS34) cDNA. Homology searching showed that eSRS34 shares amino acid sequence similarity with human platelet-derived endothelial cell growth factor. We examined the function of eSRS34 using several in vitro systems. Recombinant eSRS34 produced by a baculovirus system induced spermatogonial mitosis in testicular organ culture. Furthermore, the addition of an antibody specific for eSRS34 prevented spermatogonial mitosis induced by estradiol-17beta stimulation in a germ cell/somatic cell coculture system. We therefore conclude that eSRS34 is a "spermatogonial stem cell renewal factor."

Colon-targeted delivery of live bacterial cell biotherapeutics including microencapsulated live bacterial cells

PubMed Central

Prakash, Satya; Malgorzata Urbanska, Aleksandra

2008-01-01

There has been an ample interest in delivery of therapeutic molecules using live cells. Oral delivery has been stipulated as best way to deliver live cells to humans for therapy. Colon, in particular, is a part of gastrointestinal (GI) tract that has been proposed to be an oral targeted site. The main objective of these oral therapy procedures is to deliver live cells not only to treat diseases like colorectal cancer, inflammatory bowel disease, and other GI tract diseases like intestinal obstruction and gastritis, but also to deliver therapeutic molecules for overall therapy in various diseases such as renal failure, coronary heart disease, hypertension, and others. This review provides a comprehensive summary of recent advancement in colon targeted live bacterial cell biotherapeutics. Current status of bacterial cell therapy, principles of artificial cells and its potentials in oral delivery of live bacterial cell biotherapeutics for clinical applications as well as biotherapeutic future perspectives are also discussed in our review. PMID:19707368

Cell signaling and transcription factor genes expressed during whole body regeneration in a colonial chordate.

PubMed

Rinkevich, Yuval; Rinkevich, Baruch; Reshef, Ram

2008-10-12

The restoration of adults from fragments of blood vessels in botryllid ascidians (termed whole body regeneration [WBR]) represents an inimitable event in the chordates, which is poorly understood on the mechanistic level. To elucidate mechanisms underlying this phenomenon, a subtracted EST library for early WBR stages was previously assembled, revealing 76 putative genes belonging to major signaling pathways, including Notch/Delta, JAK/STAT, protein kinases, nuclear receptors, Ras oncogene family members, G-Protein coupled receptor (GPCR) and transforming growth factor beta (TGF-beta) signaling. RT-PCR on selected transcripts documented specific up-regulation in only regenerating fragments, pointing to a broad activation of these signaling pathways at onset of WBR. The followed-up expression pattern of seven representative transcripts from JAK/STAT signaling (Bl-STAT), the Ras oncogene family (Bl-Rap1A, Bl-Rab-33), the protein kinase family (Bl-Mnk), Bl-Cnot, Bl-Slit and Bl-Bax inhibitor, revealed systemic and site specific activations during WBR in a sub-population of circulatory cells. WBR in the non-vertebrate chordate Botrylloides leachi is a multifaceted phenomenon, presided by a complex array of cell signaling and transcription factors. Above results, provide a first insight into the whole genome molecular machinery of this unique regeneration process, and reveal the broad participation of cell signaling and transcription factors in the process. While regeneration involves the participation of specific cell populations, WBR signals are systemically expressed at the organism level.

Triiodothyronine regulates angiogenic growth factor and cytokine secretion by isolated human decidual cells in a cell-type specific and gestational age-dependent manner.

PubMed

Vasilopoulou, E; Loubière, L S; Lash, G E; Ohizua, O; McCabe, C J; Franklyn, J A; Kilby, M D; Chan, S Y

2014-06-01

Does triiodothyronine (T3) regulate the secretion of angiogenic growth factors and cytokines by human decidual cells isolated from early pregnancy? T3 modulates the secretion of specific angiogenic growth factors and cytokines, with different regulatory patterns observed amongst various isolated subpopulations of human decidual cells and with a distinct change between the first and second trimesters of pregnancy. Maternal thyroid dysfunction during early pregnancy is associated with complications of malplacentation including miscarriage and pre-eclampsia. T3 regulates the proliferation and apoptosis of fetal-derived trophoblasts, as well as promotes the invasive capability of extravillous trophoblasts (EVT). We hypothesize that T3 may also have a direct impact on human maternal-derived decidual cells, which are known to exert paracrine regulation upon trophoblast behaviour and vascular development at the uteroplacental interface. This laboratory-based study used human decidua from first (8-11 weeks; n = 18) and second (12-16 weeks; n = 12) trimester surgical terminations of apparently uncomplicated pregnancies. Primary cultures of total decidual cells, and immunomagnetic bead-isolated populations of stromal-enriched (CD10+) and stromal-depleted (CD10-) cells, uterine natural killer cells (uNK cells; CD56+) and macrophages (CD14+) were assessed for thyroid hormone receptors and transporters by immunocytochemistry. Each cell population was treated with T3 (0, 1, 10, 100 nM) and assessments were made of cell viability (MTT assay) and angiogenic growth factor and cytokine secretion (immunomediated assay). The effect of decidual cell-conditioned media on EVT invasion through Matrigel(®) was evaluated. Immunocytochemistry showed the expression of thyroid hormone transporters (MCT8, MCT10) and receptors (TRα1, TRβ1) required for thyroid hormone-responsiveness in uNK cells and macrophages from the first trimester. The viability of total decidual cells and the different

Pluripotency factors in embryonic stem cells regulate differentiation into germ layers.

PubMed

Thomson, Matt; Liu, Siyuan John; Zou, Ling-Nan; Smith, Zack; Meissner, Alexander; Ramanathan, Sharad

2011-06-10

Cell fate decisions are fundamental for development, but we do not know how transcriptional networks reorganize during the transition from a pluripotent to a differentiated cell state. Here, we asked how mouse embryonic stem cells (ESCs) leave the pluripotent state and choose between germ layer fates. By analyzing the dynamics of the transcriptional circuit that maintains pluripotency, we found that Oct4 and Sox2, proteins that maintain ESC identity, also orchestrate germ layer fate selection. Oct4 suppresses neural ectodermal differentiation and promotes mesendodermal differentiation; Sox2 inhibits mesendodermal differentiation and promotes neural ectodermal differentiation. Differentiation signals continuously and asymmetrically modulate Oct4 and Sox2 protein levels, altering their binding pattern in the genome, and leading to cell fate choice. The same factors that maintain pluripotency thus also integrate external signals and control lineage selection. Our study provides a framework for understanding how complex transcription factor networks control cell fate decisions in progenitor cells. Copyright © 2011 Elsevier Inc. All rights reserved.

Quantification of growth factor signaling and pathway cross talk by live-cell imaging

PubMed Central

Gross, Sean M.

2017-01-01

Peptide growth factors stimulate cellular responses through activation of their transmembrane receptors. Multiple intracellular signaling cascades are engaged following growth factor–receptor binding, leading to short- and long-term biological effects. Each receptor-activated signaling pathway does not act in isolation but rather interacts at different levels with other pathways to shape signaling networks that are distinctive for each growth factor. To gain insights into the specifics of growth factor-regulated interactions among different signaling cascades, we developed a HeLa cell line stably expressing fluorescent live-cell imaging reporters that are readouts for two major growth factor-stimulated pathways, Ras–Raf–Mek–ERK and phosphatidylinositol (PI) 3-kinase–Akt. Incubation of cells with epidermal growth factor (EGF) resulted in rapid, robust, and sustained ERK signaling but shorter-term activation of Akt. In contrast, hepatocyte growth factor induced sustained Akt signaling but weak and short-lived ERK activity, and insulin-like growth factor-I stimulated strong long-term Akt responses but negligible ERK signaling. To address potential interactions between signaling pathways, we employed specific small-molecule inhibitors. In cells incubated with EGF or platelet-derived growth factor-AA, Raf activation and the subsequent stimulation of ERK reduced Akt signaling, whereas Mek inhibition, which blocked ERK activation, enhanced Akt and turned transient effects into sustained responses. Our results reveal that individual growth factors initiate signaling cascades that vary markedly in strength and duration and demonstrate in living cells the dramatic effects of cross talk from Raf and Mek to PI 3-kinase and Akt. Our data further indicate how specific growth factors can encode distinct cellular behaviors by promoting complex interactions among signaling pathways. PMID:28100485

Methods for rearing Mesostoma ehrenbergii in the laboratory for cell biology experiments, including identification of factors that influence production of different egg types.

PubMed

Hoang, Carina; Ferraro-Gideon, Jessica; Gauthier, Kimberley; Forer, Arthur

2013-10-01

Mesostoma ehrenbergii spermatocytes are uniquely useful to study various aspects of cell division. Their chromosomes are large in size and few in number, with only three bivalent and four univalent chromosomes. During prometaphase, bipolar bivalents oscillate regularly to and from the poles for 1-2 hours. The univalents remain at the poles but occasionally move from one pole to the other. In addition, a precocious cleavage furrow forms during prometaphase and remains partially constricted until anaphase. Attempts to rear these animals indefinitely in laboratory conditions, however, have been mostly unsuccessful because of their reproductive strategy. M. ehrenbergii are hermaphroditic flatworms that can produce viviparous offspring (termed S eggs) and/or diapausing eggs (termed D eggs) and they follow either one of two reproductive patterns: (1) they first form S eggs and following the delivery of these eggs produce D eggs, or (2) they only produce D eggs. When only D eggs are formed, which is common under laboratory conditions, the stocks die out until the D eggs hatch, which is irregular and creates unpredictable wait times. Consequently, in order to maintain M. ehrenbergii stocks to study their spermatocytes, we examined various factors that might influence egg-type production. Feeding them daily and keeping them at 25°C favours S egg production. Currently, our cultures have reached the 53rd generation. We herein describe our rearing and dissection methods, and some experiments which led to our present rearing methods. © 2013 International Federation for Cell Biology.

Non-specific factor enhancement of human in vitro antigen-dependent antibody synthesis: role of B cell activation and T cell help.

PubMed Central

Brenner, M K; North, M E; Chadda, H R; Farrant, J

1984-01-01

Lectin-free supernatants obtained from PWM-stimulated lymphocytes, enable B cells to proliferate and secrete immunoglobulin. Both functions are augmented by the addition of irradiated T cells. In the presence of antigen, these supernatants also enhance specific anti-tetanus toxoid antibody production. The components of the supernatant responsible for these activities have a molecular weight between 30,000 and 60,000, and have the characteristics of non-specific factors: they are genetically unrestricted, and do not bind to either antigen or anti-DR affinity columns. There is no evidence that the partial T dependency of these factors is an indication that their target is a T cell. Instead, T cells appear necessary to move the B cell into a state of activation in which it becomes responsive to the factor. Alternative activation signals such as Staph. A. Cowan can substitute for T cell help in the proliferative response, but not for immunoglobulin or antibody synthesis. The implications of these results for the approaches used to detect and classify B cell growth factors are discussed. PMID:6608488

Natural Killer Cells Control Tumor Growth by Sensing a Growth Factor.

PubMed

Barrow, Alexander D; Edeling, Melissa A; Trifonov, Vladimir; Luo, Jingqin; Goyal, Piyush; Bohl, Benjamin; Bando, Jennifer K; Kim, Albert H; Walker, John; Andahazy, Mary; Bugatti, Mattia; Melocchi, Laura; Vermi, William; Fremont, Daved H; Cox, Sarah; Cella, Marina; Schmedt, Christian; Colonna, Marco

2018-01-25

Many tumors produce platelet-derived growth factor (PDGF)-DD, which promotes cellular proliferation, epithelial-mesenchymal transition, stromal reaction, and angiogenesis through autocrine and paracrine PDGFRβ signaling. By screening a secretome library, we found that the human immunoreceptor NKp44, encoded by NCR2 and expressed on natural killer (NK) cells and innate lymphoid cells, recognizes PDGF-DD. PDGF-DD engagement of NKp44 triggered NK cell secretion of interferon gamma (IFN)-γ and tumor necrosis factor alpha (TNF-α) that induced tumor cell growth arrest. A distinctive transcriptional signature of PDGF-DD-induced cytokines and the downregulation of tumor cell-cycle genes correlated with NCR2 expression and greater survival in glioblastoma. NKp44 expression in mouse NK cells controlled the dissemination of tumors expressing PDGF-DD more effectively than control mice, an effect enhanced by blockade of the inhibitory receptor CD96 or CpG-oligonucleotide treatment. Thus, while cancer cell production of PDGF-DD supports tumor growth and stromal reaction, it concomitantly activates innate immune responses to tumor expansion. Copyright © 2017 Elsevier Inc. All rights reserved.

Quantification of growth factor signaling and pathway cross talk by live-cell imaging.

PubMed

Gross, Sean M; Rotwein, Peter

2017-03-01

Peptide growth factors stimulate cellular responses through activation of their transmembrane receptors. Multiple intracellular signaling cascades are engaged following growth factor-receptor binding, leading to short- and long-term biological effects. Each receptor-activated signaling pathway does not act in isolation but rather interacts at different levels with other pathways to shape signaling networks that are distinctive for each growth factor. To gain insights into the specifics of growth factor-regulated interactions among different signaling cascades, we developed a HeLa cell line stably expressing fluorescent live-cell imaging reporters that are readouts for two major growth factor-stimulated pathways, Ras-Raf-Mek-ERK and phosphatidylinositol (PI) 3-kinase-Akt. Incubation of cells with epidermal growth factor (EGF) resulted in rapid, robust, and sustained ERK signaling but shorter-term activation of Akt. In contrast, hepatocyte growth factor induced sustained Akt signaling but weak and short-lived ERK activity, and insulin-like growth factor-I stimulated strong long-term Akt responses but negligible ERK signaling. To address potential interactions between signaling pathways, we employed specific small-molecule inhibitors. In cells incubated with EGF or platelet-derived growth factor-AA, Raf activation and the subsequent stimulation of ERK reduced Akt signaling, whereas Mek inhibition, which blocked ERK activation, enhanced Akt and turned transient effects into sustained responses. Our results reveal that individual growth factors initiate signaling cascades that vary markedly in strength and duration and demonstrate in living cells the dramatic effects of cross talk from Raf and Mek to PI 3-kinase and Akt. Our data further indicate how specific growth factors can encode distinct cellular behaviors by promoting complex interactions among signaling pathways. Copyright © 2017 the American Physiological Society.

c-kit expression profile and regulatory factors during spermatogonial stem cell differentiation

PubMed Central

2013-01-01

Background It has been proven that c-kit is crucial for proliferation, migration, survival and maturation of spermatogenic cells. A periodic expression of c-kit is observed from primordial germ cells (PGCs) to spermatogenetic stem cells (SSCs), However, the expression profile of c-kit during the entire spermatogenesis process is still unclear. This study aims to reveal and compare c-kit expression profiles in the SSCs before and after the anticipated differentiation, as well as to examine its relationship with retinoic acid (RA) stimulation. Results We have found that there are more than 4 transcripts of c-kit expressed in the cell lines and in the testes. The transcripts can be divided into short and long categories. The long transcripts include the full-length canonical c-kit transcript and the 3′ end short transcript. Short transcripts include the 3.4 kb short transcript and several truncated transcripts (1.9-3.2 kb). In addition, the 3.4 kb transcript (starting from intron 9 and covering exons 10 ~ 21) is discovered to be specifically expressed in the spermatogonia. The extracellular domain of Kit is obtained in the spermatogonia stage, but the intracellular domain (50 kDa) is constantly expressed in both SSCs and spermatogonia. The c-kit expression profiles in the testis and the spermatogonial stem cell lines vary after RA stimulation. The wave-like changes of the quantitative expression pattern of c-kit (increase initially and decrease afterwards) during the induction process are similar to that of the in vivo male germ cell development process. Conclusions There are dynamic transcription and translation changes of c-kit before and after SSCs’ anticipated differentiation and most importantly, RA is a significant upstream regulatory factor for c-kit expression. PMID:24161026

Growth Factor-Activated Stem Cell Circuits and Stromal Signals Cooperatively Accelerate Non-Integrated iPSC Reprogramming of Human Myeloid Progenitors

PubMed Central

Park, Tea Soon; Huo, Jeffrey S.; Peters, Ann; Talbot, C. Conover; Verma, Karan; Zimmerlin, Ludovic; Kaplan, Ian M.; Zambidis, Elias T.

2012-01-01

Nonviral conversion of skin or blood cells into clinically useful human induced pluripotent stem cells (hiPSC) occurs in only rare fractions (∼0.001%–0.5%) of donor cells transfected with non-integrating reprogramming factors. Pluripotency induction of developmentally immature stem-progenitors is generally more efficient than differentiated somatic cell targets. However, the nature of augmented progenitor reprogramming remains obscure, and its potential has not been fully explored for improving the extremely slow pace of non-integrated reprogramming. Here, we report highly optimized four-factor reprogramming of lineage-committed cord blood (CB) myeloid progenitors with bulk efficiencies of ∼50% in purified episome-expressing cells. Lineage-committed CD33+CD45+CD34− myeloid cells and not primitive hematopoietic stem-progenitors were the main targets of a rapid and nearly complete non-integrated reprogramming. The efficient conversion of mature myeloid populations into NANOG+TRA-1-81+ hiPSC was mediated by synergies between hematopoietic growth factor (GF), stromal activation signals, and episomal Yamanaka factor expression. Using a modular bioinformatics approach, we demonstrated that efficient myeloid reprogramming correlated not to increased proliferation or endogenous Core factor expressions, but to poised expression of GF-activated transcriptional circuits that commonly regulate plasticity in both hematopoietic progenitors and embryonic stem cells (ESC). Factor-driven conversion of myeloid progenitors to a high-fidelity pluripotent state was further accelerated by soluble and contact-dependent stromal signals that included an implied and unexpected role for Toll receptor-NFκB signaling. These data provide a paradigm for understanding the augmented reprogramming capacity of somatic progenitors, and reveal that efficient induced pluripotency in other cell types may also require extrinsic activation of a molecular framework that commonly regulates self

Host cell interactions of outer membrane vesicle-associated virulence factors of enterohemorrhagic Escherichia coli O157: Intracellular delivery, trafficking and mechanisms of cell injury

PubMed Central

Greune, Lilo; Jarosch, Kevin-André; Steil, Daniel; Zhang, Wenlan; He, Xiaohua; Lloubes, Roland; Fruth, Angelika; Kim, Kwang Sik; Schmidt, M. Alexander; Dobrindt, Ulrich; Mellmann, Alexander; Karch, Helge

2017-01-01

Outer membrane vesicles (OMVs) are important tools in bacterial virulence but their role in the pathogenesis of infections caused by enterohemorrhagic Escherichia coli (EHEC) O157, the leading cause of life-threatening hemolytic uremic syndrome, is poorly understood. Using proteomics, electron and confocal laser scanning microscopy, immunoblotting, and bioassays, we investigated OMVs secreted by EHEC O157 clinical isolates for virulence factors cargoes, interactions with pathogenetically relevant human cells, and mechanisms of cell injury. We demonstrate that O157 OMVs carry a cocktail of key virulence factors of EHEC O157 including Shiga toxin 2a (Stx2a), cytolethal distending toxin V (CdtV), EHEC hemolysin, and flagellin. The toxins are internalized by cells via dynamin-dependent endocytosis of OMVs and differentially separate from vesicles during intracellular trafficking. Stx2a and CdtV-B, the DNase-like CdtV subunit, separate from OMVs in early endosomes. Stx2a is trafficked, in association with its receptor globotriaosylceramide within detergent-resistant membranes, to the Golgi complex and the endoplasmic reticulum from where the catalytic Stx2a A1 fragment is translocated to the cytosol. CdtV-B is, after its retrograde transport to the endoplasmic reticulum, translocated to the nucleus to reach DNA. CdtV-A and CdtV-C subunits remain OMV-associated and are sorted with OMVs to lysosomes. EHEC hemolysin separates from OMVs in lysosomes and targets mitochondria. The OMV-delivered CdtV-B causes cellular DNA damage, which activates DNA damage responses leading to G2 cell cycle arrest. The arrested cells ultimately die of apoptosis induced by Stx2a and CdtV via caspase-9 activation. By demonstrating that naturally secreted EHEC O157 OMVs carry and deliver into cells a cocktail of biologically active virulence factors, thereby causing cell death, and by performing first comprehensive analysis of intracellular trafficking of OMVs and OMV-delivered virulence factors

Endogenous electromagnetic forces emissions during cell respiration as additional factor in cancer origin.

PubMed

Embi, Abraham A

2016-01-01

Seven decades ago, a seminal paper by Dr. Denham Harman in (J Gerontol 11(3):298-300, 1956), introduced a theory stating that there are good reasons for assuming that endogenous irradiation in the living cells could lead to cancer via an obscure mechanism. The main purpose of this manuscript is to shed some light in said mechanism by proposing a five-step eukaryotic cell cancer triggering cycle. In other words, a new factor is introduced, namely the recently found emissions of electromagnetic forces (EMFs) as a possible causing agent in diseases, including cancer. Introduced is an eukaryotic cell cancer inducing cycle. It includes five sequential steps of endogenous biological process that are backed by published scientific reports. It is a known fact that in order to achieve homeostasis, toxic reactive oxygen species (ROS) i.e. H2O2 molecules are broken down by the protein enzyme catalase. During this reaction EMFs are generated (Embi in AIS Physics 2(3):226-230, 2016). The EMFs recording breakthrough was possible due to the introduction of a novel table top microscopy technique to detect EMFs by using Prussian Blue Stain and nano-sized iron particles. There are different roots in molecular and clinical biology through which DNA damage could be programmed, EMFs emitted (during cell respiration) are herein proposed as an additional cause.

Soluble factors from biofilm of Candida albicans and Staphylococcus aureus promote cell death and inflammatory response.

PubMed

de Carvalho Dias, Kassia; Barbugli, Paula Aboud; de Patto, Fernanda; Lordello, Virginia Barreto; de Aquino Penteado, Letícia; Medeiros, Alexandra Ivo; Vergani, Carlos Eduardo

2017-06-30

The objective of this study was to better understand the effects of soluble factors from biofilm of single- and mixed-species Candida albicans (C. albicans) and methicillin-sensitive Staphylococcus aureus (MSSA) cultures after 36 h in culture on keratinocytes (NOK-si and HaCaT) and macrophages (J774A.1). Soluble factors from biofilms of C. albicans and MSSA were collected and incubated with keratinocytes and macrophages, which were subsequently evaluated by cell viability assays (MTT). Lactate dehydrogenase (LDH) enzyme release was measured to assess cell membrane damage to keratinocytes. Cells were analysed by brightfield microscopy after 2 and 24 h of exposure to the soluble factors from biofilm. Cell death was detected by labelling apoptotic cells with annexin V and necrotic cells with propidium iodide (PI) and was visualized via fluorescence microscopy. Soluble factors from biofilm were incubated with J774A.1 cells for 24 h; the subsequent production of NO and the cytokines IL-6 and TNF-α was measured by ELISA. The cell viability assays showed that the soluble factors of single-species C. albicans cultures were as toxic as the soluble factors from biofilm of mixed cultures, whereas the soluble factors of MSSA cultures were less toxic than those of C. albicans or mixed cultures. The soluble factors from biofilm of mixed cultures were the most toxic to the NOK-si and HaCaT cells, as confirmed by analyses of PI labelling and cell morphology. Soluble factors from biofilm of single-species MSSA and mixed-species cultures induced the production of IL-6, NO and TNF-α by J744A.1 macrophages. The production of IL-6 and NO induced by the soluble factors from biofilm of mixed cultures was lower than that induced by the soluble factors from biofilm of single-species MSSA cultures, whereas the soluble factors from biofilm of C. albicans cultures induced only low levels of NO. Soluble factors from 36-h-old biofilm of C. albicans and MSSA cultures promoted cell death and

Plasma Cell Neoplasms (Including Multiple Myeloma)—Patient Version

Cancer.gov

Plasma cell neoplasms occur when abnormal plasma cells form cancerous tumors. When there is only one tumor, the disease is called a plasmacytoma. When there are multiple tumors, it is called multiple myeloma. Start here to find information on plasma cell neoplasms treatment, research, and statistics.

Transdifferentiation of brain-derived neurotrophic factor (BDNF)-secreting mesenchymal stem cells significantly enhance BDNF secretion and Schwann cell marker proteins.

PubMed

Bierlein De la Rosa, Metzere; Sharma, Anup D; Mallapragada, Surya K; Sakaguchi, Donald S

2017-11-01

The use of genetically modified mesenchymal stem cells (MSCs) is a rapidly growing area of research targeting delivery of therapeutic factors for neuro-repair. Cells can be programmed to hypersecrete various growth/trophic factors such as brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), and nerve growth factor (NGF) to promote regenerative neurite outgrowth. In addition to genetic modifications, MSCs can be subjected to transdifferentiation protocols to generate neural cell types to physically and biologically support nerve regeneration. In this study, we have taken a novel approach by combining these two unique strategies and evaluated the impact of transdifferentiating genetically modified MSCs into a Schwann cell-like phenotype. After 8 days in transdifferentiation media, approximately 30-50% of transdifferentiated BDNF-secreting cells immunolabeled for Schwann cell markers such as S100β, S100, and p75 NTR . An enhancement was observed 20 days after inducing transdifferentiation with minimal decreases in expression levels. BDNF production was quantified by ELISA, and its biological activity tested via the PC12-TrkB cell assay. Importantly, the bioactivity of secreted BDNF was verified by the increased neurite outgrowth of PC12-TrkB cells. These findings demonstrate that not only is BDNF actively secreted by the transdifferentiated BDNF-MSCs, but also that it has the capacity to promote neurite sprouting and regeneration. Given the fact that BDNF production remained stable for over 20 days, we believe that these cells have the capacity to produce sustainable, effective, BDNF concentrations over prolonged time periods and should be tested within an in vivo system for future experiments. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Design of experiments with four-factors for a PEM fuel cell optimization

NASA Astrophysics Data System (ADS)

Olteanu, V.; Pǎtularu, L.; Popescu, C. L.; Popescu, M. O.; Crǎciunescu, A.

2017-07-01

Nowadays, many research efforts are allocated for the development of fuel cells, since they constitute a carbon-free electrical energy generator which can be used for stationary, mobile and portable applications. The maximum value of the delivered power of a fuel cell depends on many factors as: the height of plates' channels, the stoichiometry level of the air flow, the air pressure for the cathode, and of the actual operating electric current density. In this paper, two levels, full four-factors factorial experiment has been designed in order to obtain the appropriate response surface which approximates the maximum delivered power dependence of the above-mentioned factors. The optimum set of the fuel-cell factors which determine the maximum value of the delivered power was determined and a comparison between simulated and measured optimal Power versus Current Density characteristics is given.

[Transgenic cell cultures that synthesize neurotrophic factors and the possibility of therapeutic use of its cells].

PubMed

Pavlova, G V; Kanaĭkina, N N; Panteleev, D Iu; Okhotin, V E; Revishchin, A V

2012-01-01

Under the leadership of Corresponding Member of the Russian Academy of Sciences L.I. Korochkin, the Laboratory of Neurogenetics and Developmental Genetics (Institute of Gene Biology, Russian Academy of Sciences) for many years has been conducting studies of nervous system development, neural cell differentiation, and application of gene and cell technology to cure neurodegenerative diseases. The results of the study initiated by L.I. Korochkin and continued by his scientific successors support the direction of allocation of transgenic neurotrofic factors and heat-shock proteins as neuroprotectors for cell therapy. Potential for usage of promoter of HSP70 heat-shock gene of Drosophila to create transgenic constructs for therapy has been shown. Further improvement of technology of nonvirus transfer for therapeutic genes, as well as production of multicomponent genetic constructs coding several therapeutic factors with synergy effect, would stimulate creation of efficient cell medicals to cure neurodegenerative diseases.

Differentiation of embryonic stem cells into hepatocytes that coexpress coagulation factors VIII and IX.

PubMed

Cao, Jun; Shang, Chang-zhen; Lü, Li-hong; Qiu, De-chuan; Ren, Meng; Chen, Ya-jin; Min, Jun

2010-11-01

To establish an efficient culture system to support embryonic stem (ES) cell differentiation into hepatocytes that coexpress F-VIII and F-IX. Mouse E14 ES cells were cultured in differentiation medium containing sodium butyrate (SB), basic fibroblast growth factor (bFGF), and/or bone morphogenetic protein 4 (BMP4) to induce the differentiation of endoderm cells and hepatic progenitor cells. Hepatocyte growth factor, oncostatin M, and dexamethasone were then used to induce the maturation of ES cell-derived hepatocytes. The mRNA expression levels of endoderm-specific genes and hepatocyte-specific genes, including the levels of F-VIII and F-IX, were detected by RT-PCR and real-time PCR during various stages of differentiation. Protein expression was examined by immunofluorescence and Western blot. At the final stage of differentiation, flow cytometry was performed to determine the percentage of cells coexpressing F-VIII and F-IX, and ELISA was used to detect the levels of F-VIII and F-IX protein secreted into the culture medium. The expression of endoderm-specific and hepatocyte-specific markers was upregulated to highest level in response to the combination of SB, bFGF, and BMP4. Treatment with the three inducers during hepatic progenitor differentiation significantly enhanced the mRNA and protein levels of F-VIII and F-IX in ES cell-derived hepatocytes. More importantly, F-VIII and F-IX were coexpressed with high efficiency at the final stage of differentiation, and they were also secreted into the culture medium. We have established a novel in vitro differentiation protocol for ES-derived hepatocytes that coexpress F-VIII and F-IX that may provide a foundation for stem cell replacement therapy for hemophilia.

Doxorubicin resistance mediated by cytoplasmic macrophage colony-stimulating factor is associated with switch from apoptosis to autophagic cell death in MCF-7 breast cancer cells

PubMed Central

Zhang, Mengxia; Zhang, Hailiang; Tang, Fan; Wang, Yuhua; Mo, Zhongcheng; Lei, Xiaoyong

2016-01-01

Macrophage colony-stimulating factor is a vital factor in maintaining the biological function of monocyte–macrophage lineage. It is expressed in many tumor tissues and cancer cells. Recent findings indicate that macrophage colony-stimulating factor might contribute to chemoresistance, but the precise mechanisms are unclear. This study was to explore the effect of macrophage colony-stimulating factor on doxorubicin resistance in MCF-7 breast cancer cells and the possible mechanism. In the study, the human breast cancer cells, MCF-7, were transfected with macrophage colony-stimulating factor. We document that cytoplasmic macrophage colony-stimulating factor induces doxorubicin resistance and inhibits apoptosis in MCF-7 cells. Further studies demonstrated that cytoplasmic macrophage colony-stimulating factor-mediated apoptosis inhibition was dependent on the activation of PI3K/Akt/Survivin pathway. More importantly, we found that macrophage colony-stimulating factor-induced autophagic cell death in doxorubicin-treated MCF-7 cells. Taken together, we show for the first time that macrophage colony-stimulating factor-induced doxorubicin resistance is associated with the changes in cell death response with defective apoptosis and promotion of autophagic cell death. PMID:27439542

Tumor necrosis factor-alpha stimulates the production of squamous cell carcinoma antigen in normal squamous cells.

PubMed

Numa, F; Takeda, O; Nakata, M; Nawata, S; Tsunaga, N; Hirabayashi, K; Suminami, Y; Kato, H; Hamanaka, S

1996-01-01

Squamous cell carcinoma (SCC) antigen, a tumor marker of squamous cell carcinoma, is also increased in several nonmalignant skin lesions, e.g. pemphigus. The aim of the present investigation was to determine if tumor necrosis factor-alpha (TNF-alpha), one of the important environmental factors, stimulated the production of SCC antigen in the normal squamous cells. The exposure of normal human epidermal keratinocytes to TNF-alpha (100 IU/ml) for 72 h greatly increased the SCC antigen production. The stimulatory effect of TNF-alpha (1,000 IU/ml) on the production of SCC antigen was also observed in the normal squamous epithelium tissue. These results would be helpful for understanding the increase of SCC antigen in several nonmalignant skin disorders.

Leonurine protects against tumor necrosis factor-α-mediated inflammation in human umbilical vein endothelial cells.

PubMed

Liu, Xinhua; Pan, Lilong; Wang, Xianli; Gong, Qihai; Zhu, Yi Zhun

2012-05-01

Leonurine, a bioactive alkaloid compound in Herba leonuri, has various pharmacological activities, including antioxidant and anti-apoptotic capacities. This study was conducted to test the hypothesis that leonurine was able to attenuate tumor necrosis factor (TNF)-α-induced human umbilical vein endothelial cells (HUVEC) activation and the underlying molecular mechanisms. Mitogen-activated protein kinases (MAPK) activation, nuclear factor-κB (NF-κB) activation, and inflammatory mediators expression were detected by Western blot or enzyme-liked immunosorbent assay, intracellular reactive oxygen species (ROS) and NF-κB p65 translocation were measured by immunofluorescence, endothelial cell-monocyte interaction was detected by microscope. Leonurine inhibited U937 cells adhesion to TNF-α-activated HUVEC in a concentration dependent manner. Treatment with leonurine blocked TNF-α-induced mRNA and protein expression of adhesion molecules (intercellular adhesion molecule-1 and vascular cell adhesion molecule-1), cyclooxygenase-2, and monocyte chemoattractant protein-1 in endothelial cells. In addition, leonurine attenuated TNF-α-induced intracellular ROS production in HUVEC. Furthermore, leonurine also suppressed the TNF-α-activated p38 phosphorylation and IκBα degradation. Subsequently, reduced NF-κB p65 phosphorylation, nuclear translocation, and DNA-binding activity were also observed. Our results demonstrated for the first time that the anti-inflammatory properties of leonurine in endothelial cells, at least in part, through suppression of NF-κB activation, which may have a potential therapeutic use for inflammatory vascular diseases. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

GP88 (PC-Cell Derived Growth Factor, progranulin) stimulates proliferation and confers letrozole resistance to aromatase overexpressing breast cancer cells

PubMed Central

2011-01-01

Background Aromatase inhibitors (AI) that inhibit breast cancer cell growth by blocking estrogen synthesis have become the treatment of choice for post-menopausal women with estrogen receptor positive (ER+) breast cancer. However, some patients display de novo or acquired resistance to AI. Interactions between estrogen and growth factor signaling pathways have been identified in estrogen-responsive cells as one possible reason for acquisition of resistance. Our laboratory has characterized an autocrine growth factor overexpressed in invasive ductal carcinoma named PC-Cell Derived Growth Factor (GP88), also known as progranulin. In the present study, we investigated the role GP88 on the acquisition of resistance to letrozole in ER+ breast cancer cells Methods We used two aromatase overexpressing human breast cancer cell lines MCF-7-CA cells and AC1 cells and their letrozole resistant counterparts as study models. Effect of stimulating or inhibiting GP88 expression on proliferation, anchorage-independent growth, survival and letrozole responsiveness was examined. Results GP88 induced cell proliferation and conferred letrozole resistance in a time- and dose-dependent fashion. Conversely, naturally letrozole resistant breast cancer cells displayed a 10-fold increase in GP88 expression when compared to letrozole sensitive cells. GP88 overexpression, or exogenous addition blocked the inhibitory effect of letrozole on proliferation, and stimulated survival and soft agar colony formation. In letrozole resistant cells, silencing GP88 by siRNA inhibited cell proliferation and restored their sensitivity to letrozole. Conclusion Our findings provide information on the role of an alternate growth and survival factor on the acquisition of aromatase inhibitor resistance in ER+ breast cancer. PMID:21658239

Endothelial connexin 32 regulates tissue factor expression induced by inflammatory stimulation and direct cell-cell interaction with activated cells.

PubMed

Okamoto, Takayuki; Akita, Nobuyuki; Hayashi, Tatsuya; Shimaoka, Motomu; Suzuki, Koji

2014-10-01

Endothelial cell (EC) interacts with adjacent EC through gap junction, and abnormal expression or function of Cxs is associated with cardiovascular diseases. In patients with endothelial dysfunction, the up-regulation of tissue factor (TF) expression promotes the pathogenic activation of blood coagulation, however the relationship between gap junctions and TF expression in ECs remains uncharacterized. ECs express the gap junction (GJ) proteins connexin32 (Cx32), Cx37, Cx40 and Cx43. We investigated the role of endothelial gap junctions, particularly Cx32, in modulating TF expression during vascular inflammation. Human umbilical vein endothelial cells (HUVECs) were stimulated with tumor necrosis factor-α (TNF-α) and TF activity was assessed in the presence of GJ blockers and an inhibitory anti-Cx32 monoclonal antibody. Treatment with GJ blockers and anti-Cx32 monoclonal antibody enhanced the TNF-α-induced TF activity and mRNA expression in HUVECs. TNF-α-activated effector HUVECs or mouse MS-1 cells were co-cultured with non-stimulated acceptor HUVECs and TF expression in acceptor HUVECs was detected. Effector EC induced TF expression in adjacent acceptor HUVECs through direct cell-cell interaction. Cell-cell interaction induced TF expression was reduced by anti-intercellular adhesion molecule-1 (ICAM1) monoclonal antibody. Soluble ICAM1-Fc fusion protein promotes TF expression. GJ blockers and anti-Cx32 monoclonal antibody enhanced TF expression induced by cell-cell interaction and ICAM1-Fc treatment. Blockade of endothelial Cx32 increased TF expression induced by TNF-α stimulation and cell-cell interaction which was at least partly dependent upon ICAM1. These results suggest that direct Cx32-mediated interaction modulates TF expression in ECs during vascular inflammation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Hypoxia-inducible factors regulate pluripotency factor expression by ZNF217- and ALKBH5-mediated modulation of RNA methylation in breast cancer cells.

PubMed

Zhang, Chuanzhao; Zhi, Wanqing Iris; Lu, Haiquan; Samanta, Debangshu; Chen, Ivan; Gabrielson, Edward; Semenza, Gregg L

2016-10-04

Exposure of breast cancer cells to hypoxia increases the percentage of breast cancer stem cells (BCSCs), which are required for tumor initiation and metastasis, and this response is dependent on the activity of hypoxia-inducible factors (HIFs). We previously reported that exposure of breast cancer cells to hypoxia induces the ALKBH5-mediated demethylation of N6-methyladenosine (m6A) in NANOG mRNA leading to increased expression of NANOG, which is a pluripotency factor that promotes BCSC specification. Here we report that exposure of breast cancer cells to hypoxia also induces ZNF217-dependent inhibition of m6A methylation of mRNAs encoding NANOG and KLF4, which is another pluripotency factor that mediates BCSC specification. Although hypoxia induced the BCSC phenotype in all breast-cancer cell lines analyzed, it did so through variable induction of pluripotency factors and ALKBH5 or ZNF217. However, in every breast cancer line, the hypoxic induction of pluripotency factor and ALKBH5 or ZNF217 expression was HIF-dependent. Immunohistochemistry revealed that expression of HIF-1α and ALKBH5 was concordant in all human breast cancer biopsies analyzed. ALKBH5 knockdown in MDA-MB-231 breast cancer cells significantly decreased metastasis from breast to lungs in immunodeficient mice. Thus, HIFs stimulate pluripotency factor expression and BCSC specification by negative regulation of RNA methylation.

Chitosan stabilizes platelet growth factors and modulates stem cell differentiation toward tissue regeneration.

PubMed

Busilacchi, Alberto; Gigante, Antonio; Mattioli-Belmonte, Monica; Manzotti, Sandra; Muzzarelli, Riccardo A A

2013-10-15

The idea of using chitosan as a functional delivery aid to support simultaneously PRP, stem cells and growth factors (GF) is associated with the intention to use morphogenic biomaterials to modulate the natural healing sequence in bone and other tissues. For example, chitosan-chondroitin sulfate loaded with platelet lysate was included in a poly(D,L-lactate) foam that was then seeded with human adipose-derived stem cells and cultured in vitro under osteogenic stimulus: the platelet lysate provided to the bone tissue the most suitable assortment of GF which induces the osteogenic differentiation of the mesenchymal stem cells. PDGF, FGF, IGF and TGF-β were protagonists in the repair of callus fractures. The release of GF from the composites of chitosan-PRP and either nano-hydroxyapatite or tricalcium phosphate was highly beneficial for enhancing MSC proliferation and differentiation, thus qualifying chitosan as an excellent vehicle. A number of biochemical characteristics of chitosan exert synergism with stem cells in the regeneration of soft tissues. Copyright © 2013 Elsevier Ltd. All rights reserved.

Nuclear factor E2-related factor-2 has a differential impact on MCT1 and MCT4 lactate carrier expression in colonic epithelial cells: a condition favoring metabolic symbiosis between colorectal cancer and stromal cells.

PubMed

Diehl, K; Dinges, L-A; Helm, O; Ammar, N; Plundrich, D; Arlt, A; Röcken, C; Sebens, S; Schäfer, H

2018-01-04

Malignant tumors, such as colorectal cancer (CRC), are heterogeneous diseases characterized by distinct metabolic phenotypes. These include Warburg- and reverse Warburg phenotypes depending on differential distribution of the lactate carrier proteins monocarboxylate transporter-4 and -1 (MCT4 and MCT1). Here, we elucidated the role of the antioxidant transcription factor nuclear factor E2-related factor-2 (Nrf2) as the key regulator of cellular adaptation to inflammatory/environmental stress in shaping the metabolism toward a reverse Warburg phenotype in malignant and premalignant colonic epithelial cells. Immunohistochemistry of human CRC tissues revealed reciprocal expression of MCT1 and MCT4 in carcinoma and stroma cells, respectively, accompanied by strong epithelial Nrf2 activation. In colorectal tissue from inflammatory bowel disease patients, MCT1 and Nrf2 were coexpressed as well, relating to CD68+inflammatory infiltrates. Indirect coculture of human NCM460 colonocytes with M1- but not M2 macrophages induces MCT1 as well as G6PD, LDHB and TALDO expression, whereas MCT4 expression was decreased. Nrf2 knockdown or reactive oxygen species (ROS) scavenging blocked these coculture effects in NCM460 cells. Likewise, Nrf2 knockdown inhibited similar effects of tBHQ-mediated Nrf2 activation on NCM460 and HCT15 CRC cells. M1 coculture or Nrf2 activation/overexpression greatly altered the lactate uptake but not glucose uptake and mitochondrial activities in these cells, reflecting the reverse Warburg phenotype. Depending on MCT1-mediated lactate uptake, Nrf2 conferred protection from TRAIL-induced apoptosis in NCM460 and HCT15 cells. Moreover, metabolism-dependent clonal growth of HCT15 cells was induced by Nrf2-dependent activation of MCT1-driven lactate exchange. These findings indicate that Nrf2 has an impact on the metabolism already in premalignant colonic epithelial cells exposed to inflammatory M1 macrophages, an effect accompanied by growth and survival

RNA Expression Profiling Reveals Differentially Regulated Growth Factor and Receptor Expression in Redirected Cancer Cells.

PubMed

Schmucker, Hannah S; Park, Jang Pyo; Coissieux, Marie-May; Bentires-Alj, Mohamed; Feltus, F Alex; Booth, Brian W

2017-05-01

Tumorigenic cells can be redirected to adopt a normal phenotype when transplanted into cleared mammary fat pads of juvenile female mice in specific ratios with normal epithelial cells. The redirected tumorigenic cells enter stem cell niches and provide progeny that differentiate into all mammary epithelial subtypes. We have developed an in vitro model that mimics the in vivo phenomenon. The shift in phenotype to redirection should be accomplished through a return to a normal gene expression state. To measure this shift, we interrogated the transcriptome of various in vitro model states in search for casual genes. For this study, expression of growth factors, cytokines, and their associated receptors was examined. In all, we queried 251 growth factor and cytokine-related genes. We found numerous growth factor and cytokine genes whose expression levels switched from expression levels seen in cancer cells to expression levels observed in normal cells. The comparisons of gene expression between normal mammary epithelial cells, tumor-derived cells, and redirected cancer cells have revealed insight into active and inactive growth factors and cytokines in cancer cell redirection.

Mouse glucocorticoid-induced tumor necrosis factor receptor ligand is costimulatory for T cells

PubMed Central

Tone, Masahide; Tone, Yukiko; Adams, Elizabeth; Yates, Stephen F.; Frewin, Mark R.; Cobbold, Stephen P.; Waldmann, Herman

2003-01-01

Recently, agonist antibodies to glucocorticoid-induced tumor necrosis factor receptor (GITR) (tumor necrosis factor receptor superfamily 18) have been shown to neutralize the suppressive activity of CD4+CD25+ regulatory T cells. It was anticipated that this would be the role of the physiological ligand. We have identified and expressed the gene for mouse GITR ligand and have confirmed that its interaction with GITR reverses suppression by CD4+CD25+ T cells. It also, however, provides a costimulatory signal for the antigen-driven proliferation of naïve T cells and polarized T helper 1 and T helper 2 clones. RT-PCR and mAb staining revealed mouse GITR ligand expression in dendritic cells, macrophages, and B cells. Expression was controlled by the transcription factor NF-1 and potentially by alternative splicing of mRNA destabilization sequences. PMID:14608036

The role of endocytic Rab GTPases in regulation of growth factor signaling and the migration and invasion of tumor cells

PubMed Central

Porther, N; Barbieri, MA

2015-01-01

Metastasis is characterized pathologically by uncontrolled cell invasion, proliferation, migration and angiogenesis. It is a multistep process that encompasses the modulation of membrane permeability and invasion, cell spreading, cell migration and proliferation of the extracellular matrix, increase in cell adhesion molecules and interaction, decrease in cell attachment and induced survival signals and propagation of nutrient supplies (blood vessels). In cancer, a solid tumor cannot expand and spread without a series of synchronized events. Changes in cell adhesion receptor molecules (e.g., integrins, cadherin-catenins) and protease expressions have been linked to tumor invasion and metastasis. It has also been determined that ligand-growth factor receptor interactions have been associated with cancer development and metastasis via the endocytic pathway. Specifically, growth factors, which include IGF-1 and IGF-2 therapy, have been associated with most if not all of the features of metastasis. In this review, we will revisit some of the key findings on perhaps one of the most important hallmarks of cancer metastasis: cell migration and cell invasion and the role of the endocytic pathway in mediating this phenomenon PMID:26317377

Retrospective cohort study of prognostic factors in patients with oral cavity and oropharyngeal squamous cell carcinoma.

PubMed

Carrillo, José F; Carrillo, Liliana C; Cano, Ana; Ramirez-Ortega, Margarita C; Chanona, Jorge G; Avilés, Alejandro; Herrera-Goepfert, Roberto; Corona-Rivera, Jaime; Ochoa-Carrillo, Francisco J; Oñate-Ocaña, Luis F

2016-04-01

Prognostic factors in oral cavity and oropharyngeal squamous cell carcinoma (SCC) are debated. The purpose of this study was to investigate the association of prognostic factors with oncologic outcomes. Patients with oral cavity and oropharyngeal SCC treated from 1997 to 2012 were included in this retrospective cohort study. Associations of prognostic factors with locoregional recurrence (LRR) or overall survival (OS) were analyzed using the logistic regression and the Cox models. Six hundred thirty-four patients were included in this study; tumor size, surgical margins, and N classification were associated with LRR (p < .0001); considering histopathology: perineural invasion, lymphocytic infiltration, infiltrative borders, and N classification were significant determinants of LRR. Tumor size, N classification, alcoholism, and surgical margins were associated with OS (p < .0001); considering pathologic prognostic factors, perivascular invasion, islands borders, and surgical margins were independently associated with OS (p < .0001). Surgical margins, perineural and perivascular invasion, lymphocytic infiltration, and infiltrative patterns of tumor invasion are significant prognostic factors in oral cavity and oropharyngeal SCC. © 2015 Wiley Periodicals, Inc.

Effects of basic fibroblast growth factor and insulin-like growth factor on cultured cartilage cells from skate Raja porasa

NASA Astrophysics Data System (ADS)

Fan, Tingjun; Jin, Lingyun; Wang, Xiaofeng

2003-12-01

Effects of basic fibroblast growth factor (bFGF) and insulin-like growth factor II (IGF-II) on cartilage cells from proboscis of skate, Raja porasa Günther, were investigated in this study. The cartilage cells were cultured in 20% FBS-supplemented MEM medium at 24°C. Twelve hours after culture initiation, the cartilage cells were treated with bFGF and IGF-II at different concentration combinations. It was found that 20 ng/ml of bFGF or 80 ng/ml of IGF-II was enough to have obvious stimulating effect on the growth and division of skate cartilage cells. Test of bFGF and IGF-II together, revealed that 20 ng/ml of bFGF and 80 ng/ml of IGF-II together had the best stimulating effect on the growth and division of skate cartilage cells. The cartilage cells cultured could form a monolayer at day 7.

Develop a PWL System for Dense Graded Hot Mix Asphalt Construction, Including Pay Factors

DOT National Transportation Integrated Search

2015-01-01

This research project developed a PWL system that the Nevada DOT can effectively implement on the construction of dense graded HMA mixtures. The PWL system includes pay factors that are based on pavement performance indicators such as rutting and cra...

Protopine inhibits heterotypic cell adhesion in MDA-MB-231 cells through down-regulation of multi-adhesive factors.

PubMed

He, Kai; Gao, Jian-Li

2014-01-01

A Chinese herb Corydalis yanhusuo W.T. Wang that showed anticancer and anti-angiogenesis effects in our previous studies was presented for further studies. In the present study, we studied the anticancer proliferation and adhesion effects of five alkaloids which were isolated from Corydalis yanhusuo. MTT dose response curves, cell migration assay, cell invasion assay, as well as three types of cell adhesive assay were performed on MDA-MB-231 human breast cancer cells. The mechanism of the compounds on inhibiting heterotypic cell adhesion were further explored by determining the expression of epidermal growth factor receptor (EGFR), Intercellular adhesion molecule 1 (ICAM-1), αv-integrin, β1-integrin and β5-integrin by western blotting assay. In five tested alkaloids, only protopine exhibited anti-adhesive and anti-invasion effects in MDA-MB-231 cells, which contributed to the anti-metastasis effect of Corydalis yanhusuo. The results showed that after treatment with protopine for 90 min, the expression of EGFR, ICAM-1, αv-integrin, β1-integrin and β5-integrin were remarkably reduced. The present results suggest that protopine seems to inhibit the heterotypic cell adhesion between MDA-MB-231 cells, and human umbilical vein endothelial cells by changing the expression of adhesive factors.

Krüppel Like Factors Family Expression in Cervical Cancer Cells.

PubMed

Marrero-Rodríguez, Daniel; la Cruz, Hugo Arreola-De; Taniguchi-Ponciano, Keiko; Gomez-Virgilio, Laura; Huerta-Padilla, Victor; Ponce-Navarrete, Gustavo; Andonegui-Elguera, Sergio; Jimenez-Vega, Florinda; Romero-Morelos, Pablo; Rodriguez-Esquivel, Miriam; Meraz-Rios, Marco; Figueroa-Corona, Ma Del Pilar; Monroy, Alberto; Pérez-González, Oscar; Salcedo, Mauricio

2017-05-01

Krüppel Like Factors (KLF) refers to a family of seventeen members of transcription factors. Involved in several cellular processes. As other cancer types, Cervical Cancer (CC) presents molecular deregulations in transcription factors, but especially Human Papilloma Virus (HPV) sequences. Here in this work we analyzed the mRNA expression of all KLF family members in CC-derived cell lines and CC tissues. The cell lines used were HeLa, INBL, RoVa, C4-I, Ms751, ViPa, CaLo, SiHa, CaSki, C33a and ViBo and the non-tumorigenic HaCaT. mRNA expression was analyzed by means of expression microarray and RT-PCR, and KLF5 protein by immunofluorescence. The cell lines were grouped according to HPV genotype as HPV16, HPV18 positive or HPV negative cells. Heterogeneous expression was observed among the cell lines. Despite the heterogeneous expression profile, KLF3, -5, -12, -15 and -16 transcripts were present in all cell lines, KLF4 and -10 which were not expressed in CaSki; KLF11 and 13 were not expressed by Vipa and C4-I, and KLF7 was not expressed by C4-I and Rova. The CC tissue analysis shows expression of most of the KLF members, such as KLF5. KLF5 immunosignal was positive in the three cell lines analyzed. We suggest that KLF expression could not be related to HPV presence/genotype, at least at transcriptional level, and the expression of KLF family members may be necessary in the biology of the CC cells. Copyright © 2017 IMSS. Published by Elsevier Inc. All rights reserved.

Different Effects of Human Umbilical Cord Mesenchymal Stem Cells on Glioblastoma Stem Cells by Direct Cell Interaction or Via Released Soluble Factors.

PubMed

Bajetto, Adriana; Pattarozzi, Alessandra; Corsaro, Alessandro; Barbieri, Federica; Daga, Antonio; Bosio, Alessia; Gatti, Monica; Pisaturo, Valerio; Sirito, Rodolfo; Florio, Tullio

2017-01-01

Glioblastoma (GBM), the most common primary brain tumor in adults, is an aggressive, fast-growing and highly vascularized tumor, characterized by extensive invasiveness and local recurrence. In GBM and other malignancies, cancer stem cells (CSCs) are believed to drive invasive tumor growth and recurrence, being responsible for radio- and chemo-therapy resistance. Mesenchymal stem cells (MSCs) are multipotent progenitors that exhibit tropism for tumor microenvironment mediated by cytokines, chemokines and growth factors. Initial studies proposed that MSCs might exert inhibitory effects on tumor development, although, to date, contrasting evidence has been provided. Different studies reported either MSC anti-tumor activity or their support to tumor growth. Here, we examined the effects of umbilical cord (UC)-MSCs on in vitro GBM-derived CSC growth, by direct cell-to-cell interaction or indirect modulation, via the release of soluble factors. We demonstrate that UC-MSCs and CSCs exhibit reciprocal tropism when co-cultured as 3D spheroids and their direct cell interaction reduces the proliferation of both cell types. Contrasting effects were obtained by UC-MSC released factors: CSCs, cultured in the presence of conditioned medium (CM) collected from UC-MSCs, increased proliferation rate through transient ERK1/2 and Akt phosphorylation/activation. Analysis of the profile of the cytokines released by UC-MSCs in the CM revealed a strong production of molecules involved in inflammation, angiogenesis, cell migration and proliferation, such as IL-8, GRO, ENA-78 and IL-6. Since CXC chemokine receptor 2 (CXCR2), a receptor shared by several of these ligands, is expressed in GBM CSCs, we evaluated its involvement in CSC proliferation induced by UC-MSC-CM. Using the CXCR2 antagonist SB225002, we observed a partial but statistically significant inhibition of CSC proliferation and migration induced by the UC-MSC-released cytokines. Conversely, CXCR2 blockade did not reduce the

Using minimalist self-assembling peptides as hierarchical scaffolds to stabilise growth factors and promote stem cell integration in the injured brain.

PubMed

Rodriguez, A L; Bruggeman, K F; Wang, Y; Wang, T Y; Williams, R J; Parish, C L; Nisbet, D R

2018-03-01

Neurotrophic growth factors are effective in slowing progressive degeneration and/or promoting neural repair through the support of residual host and/or transplanted neurons. However, limitations including short half-life and enzyme susceptibility of growth factors highlight the need for alternative strategies to prolong localised delivery at a site of injury. Here, we establish the utility of minimalist N-fluorenylmethyloxycarbonyl (Fmoc) self-assembling peptides (SAPs) as growth factor delivery vehicle, targeted at supporting neural transplants in an animal model of Parkinson's disease. The neural tissue-specific SAP, Fmoc-DIKVAV, demonstrated sustained release of glial cell line derived neurotrophic factor, up to 172 hr after gel loading. This represents a significant advance in drug delivery, because its lifetime in phosphate buffered saline was less than 1 hr. In vivo transplantation of neural progenitor cells, together with our growth factor-loaded material, into the injured brain improved graft survival compared with cell transplants alone. We show for the first time the use of minimalist Fmoc-SAP in an in vivo disease model for sustaining the delivery of neurotrophic growth factors, facilitating their spatial and temporal delivery in vivo, whilst also providing an enhanced niche environment for transplanted cells. Copyright © 2017 John Wiley & Sons, Ltd.