[Lentivirus-mediated shRNA silencing of LAMP2A inhibits the proliferation of multiple myeloma cells].

PubMed

Li, Lixuan; Li, Jia

2015-05-01

To study the effects of lentivirus-mediated short hairpin RNA (shRNA) silencing of lysosome-associated membrane protein type 2A (LAMP2A) expression on the proliferation of multiple myeloma cells. The constructed shRNA lentiviral vector was applied to infect human multiple myeloma cell line MM.1S, and stable expression cell line was obtained by puromycin screening. Western blotting was used to verify the inhibitory effect on LAMP2A protein expression. MTT assay was conducted to detect the effect of knocked-down LAMP2A on MM.1S cell proliferation, and the anti-tumor potency of suberoylanilide hydroxamic acid (SAHA) against the obtained MM.1S LAMP2A(shRNA) stable cell line. Lactate assay was performed to observe the impact of low LAMP2A expression on cell glycolysis. The stable cell line with low LAMP2A expression were obtained with the constructed human LAMP2A-shRNA lentiviral vector. Down-regulation of LAMP2A expression significantly inhibited MM.1S cell proliferation and enhanced the anti-tumor activity of SAHA. Interestingly, decreased LAMP2A expression also inhibited MM.1S cell lactic acid secretion. Down-regulation of LAMP2A expression could inhibit cell proliferation in multiple myeloma cells.

[Polyamines and their role in tumor growth].

PubMed

Godlewska, Joanna; Peczyńska-Czoch, Wanda

2002-01-01

The polyamines-putrescine, spermidine and spermine--are normal constituents of prokariotic and eukariotic cells. These small polycationic, aliphatic compounds are essential for normal cell proliferation. Cells cease to proliferate, when they are depleted of their polyamines, but resume a normal growth rate after supplementation with these compounds. Because of the sustained increase in polyamine biosynthesis in preneoplastic and neoplastic tissues, a great deal of interest has been given to the polyamine biosynthesis, network, and uptake systems as a target in antineoplastic strategies.

Polyphosphate induces matrix metalloproteinase-3-mediated proliferation of odontoblast-like cells derived from induced pluripotent stem cells

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

Ozeki, Nobuaki; Hase, Naoko; Yamaguchi, Hideyuki

2015-05-01

Inorganic polyphosphate [Poly(P)] may represent a physiological source of phosphate and has the ability to induce bone differentiation in osteoblasts. We previously reported that cytokine-induced matrix metalloproteinase (MMP)-3 accelerates the proliferation of purified odontoblast-like cells. In this study, MMP-3 small interfering RNA (siRNA) was transfected into odontoblast-like cells derived from induced pluripotent stem cells to investigate whether MMP-3 activity is induced by Poly(P) and/or is associated with cell proliferation and differentiation into odontoblast-like cells. Treatment with Poly(P) led to an increase in both cell proliferation and additional odontoblastic differentiation. Poly(P)-treated cells showed a small but significant increase in dentin sialophosphoproteinmore » (DSPP) and dentin matrix protein-1 (DMP-1) mRNA expression, which are markers of mature odontoblasts. The cells also acquired additional odontoblast-specific properties including adoption of an odontoblastic phenotype typified by high alkaline phosphatase (ALP) activity and a calcification capacity. In addition, Poly(P) induced expression of MMP-3 mRNA and protein, and increased MMP-3 activity. MMP-3 siRNA-mediated disruption of the expression of these effectors potently suppressed the expression of odontoblastic biomarkers ALP, DSPP, and DMP-1, and blocked calcification. Interestingly, upon siRNA-mediated silencing of MMP-3, we noted a potent and significant decrease in cell proliferation. Using specific siRNAs, we revealed that a unique signaling cascade, Poly(P)→MMP-3→DSPP and/or DMP-1, was intimately involved in the proliferation of odontoblast-like cells. - Highlights: • Polyphosphate increases proliferation of iPS cell-derived odontoblast-like cells. • Polyphosphate-induced MMP-3 results in an increase of cell proliferation. • Induced cell proliferation involves MMP-3, DSPP, and/or DMP-1 sequentially. • Induced MMP-3 also results in an increase of odontoblastic differentiation.« less

Inhibitory activity of synthesized acetylated Procyanidin B1 analogs against HeLa S3 cells proliferation.

PubMed

Okamoto, Syuhei; Ishihara, Sayaka; Okamoto, Taisuke; Doi, Syoma; Harui, Kota; Higashino, Yusuke; Kawasaki, Takashi; Nakajima, Noriyuki; Saito, Akiko

2014-02-04

Proanthocyanidins, also known as condensed tannins and/or oligomeric flavonoids, occur in many edible plants and have various interesting biological activities. Previously, we reported a synthetic method for the preparation of various procyanidins in pure form and described their biological activities. Here, we describe the synthesis of procyanidin B1 acetylated analogs and discuss their inhibition activities against HeLa S3 cell proliferation. Surprisingly, the lower-unit acetylated procyanidin B1 strongly inhibited the proliferation of HeLa S3 cells. This molecule showed much stronger inhibitory activity than did epigallocatechin-3-O-gallate (EGCG), green tea polyphenol, and dimeric compounds that included EGCG as a unit. This result suggests that the phenolic hydroxyl groups of the upper-units in flavan-3-ols are important for their inhibitory activity against cancer cell proliferation and that a hydrophobic lower unit dimer enhances this activity.

In vitro proliferation of human osteogenic cells in presence of different commercial bone substitute materials combined with enamel matrix derivatives

PubMed Central

2009-01-01

Background Cellular reactions to alloplastic bone substitute materials (BSM) are a subject of interest in basic research. In regenerative dentistry, these bone grafting materials are routinely combined with enamel matrix derivatives (EMD) in order to additionally enhance tissue regeneration. Materials and methods The aim of this study was to evaluate the proliferative activity of human osteogenic cells after incubation over a period of seven days with commercial BSM of various origin and chemical composition. Special focus was placed on the potential additional benefit of EMD on cellular proliferation. Results Except for PerioGlas®, osteogenic cell proliferation was significantly promoted by the investigated BSM. The application of EMD alone also resulted in significantly increased cellular proliferation. However, a combination of BSM and EMD resulted in only a moderate additional enhancement of osteogenic cell proliferation. Conclusion The application of most BSM, as well as the exclusive application of EMD demonstrated a positive impact on the proliferation of human osteogenic cells in vitro. In order to increase the benefit from substrate combination (BSM + EMD), further studies on the interactions between BSM and EMD are needed. PMID:19909545

Culture Medium Supplements Derived from Human Platelet and Plasma: Cell Commitment and Proliferation Support

PubMed Central

Muraglia, Anita; Nguyen, Van Thi; Nardini, Marta; Mogni, Massimo; Coviello, Domenico; Dozin, Beatrice; Strada, Paolo; Baldelli, Ilaria; Formica, Matteo; Cancedda, Ranieri; Mastrogiacomo, Maddalena

2017-01-01

Present cell culture medium supplements, in most cases based on animal sera, are not fully satisfactory especially for the in vitro expansion of cells intended for human cell therapy. This paper refers to (i) an heparin-free human platelet lysate (PL) devoid of serum or plasma components (v-PL) and (ii) an heparin-free human serum derived from plasma devoid of PL components (Pl-s) and to their use as single components or in combination in primary or cell line cultures. Human mesenchymal stem cells (MSC) primary cultures were obtained from adipose tissue, bone marrow, and umbilical cord. Human chondrocytes were obtained from articular cartilage biopsies. In general, MSC expanded in the presence of Pl-s alone showed a low or no proliferation in comparison to cells grown with the combination of Pl-s and v-PL. Confluent, growth-arrested cells, either human MSC or human articular chondrocytes, treated with v-PL resumed proliferation, whereas control cultures, not supplemented with v-PL, remained quiescent and did not proliferate. Interestingly, signal transduction pathways distinctive of proliferation were activated also in cells treated with v-PL in the absence of serum, when cell proliferation did not occur, indicating that v-PL could induce the cell re-entry in the cell cycle (cell commitment), but the presence of serum proteins was an absolute requirement for cell proliferation to happen. Indeed, Pl-s alone supported cell growth in constitutively activated cell lines (U-937, HeLa, HaCaT, and V-79) regardless of the co-presence of v-PL. Plasma- and plasma-derived serum were equally able to sustain cell proliferation although, for cells cultured in adhesion, the Pl-s was more efficient than the plasma from which it was derived. In conclusion, the cells expanded in the presence of the new additives maintained their differentiation potential and did not show alterations in their karyotype. PMID:29209609

Viability and proliferation of endothelial cells upon exposure to GaN nanoparticles.

PubMed

Braniste, Tudor; Tiginyanu, Ion; Horvath, Tibor; Raevschi, Simion; Cebotari, Serghei; Lux, Marco; Haverich, Axel; Hilfiker, Andres

2016-01-01

Nanotechnology is a rapidly growing and promising field of interest in medicine; however, nanoparticle-cell interactions are not yet fully understood. The goal of this work was to examine the interaction between endothelial cells and gallium nitride (GaN) semiconductor nanoparticles. Cellular viability, adhesion, proliferation, and uptake of nanoparticles by endothelial cells were investigated. The effect of free GaN nanoparticles versus the effect of growing endothelial cells on GaN functionalized surfaces was examined. To functionalize surfaces with GaN, GaN nanoparticles were synthesized on a sacrificial layer of zinc oxide (ZnO) nanoparticles using hydride vapor phase epitaxy. The uptake of GaN nanoparticles by porcine endothelial cells was strongly dependent upon whether they were fixed to the substrate surface or free floating in the medium. The endothelial cells grown on surfaces functionalized with GaN nanoparticles demonstrated excellent adhesion and proliferation, suggesting good biocompatibility of the nanostructured GaN.

Cell density-dependent differential proliferation of neural stem cells on omnidirectional nanopore-arrayed surface.

PubMed

Cha, Kyoung Je; Kong, Sun-Young; Lee, Ji Soo; Kim, Hyung Woo; Shin, Jae-Yeon; La, Moonwoo; Han, Byung Woo; Kim, Dong Sung; Kim, Hyun-Jung

2017-10-12

Recently, the importance of surface nanotopography in the determination of stem cell fate and behavior has been revealed. In the current study, we generated polystyrene cell-culture dishes with an omnidirectional nanopore arrayed surface (ONAS) (diameter: 200 nm, depth: 500 nm, center-to-center distance: 500 nm) and investigated the effects of nanotopography on rat neural stem cells (NSCs). NSCs cultured on ONAS proliferated better than those on the flat surface when cell density was low and showed less spontaneous differentiation during proliferation in the presence of mitogens. Interestingly, NSCs cultured on ONAS at clonal density demonstrated a propensity to generate neurospheres, whereas those on the flat surface migrated out, proliferated as individuals, and spread out to attach to the surface. However, the differential patterns of proliferation were cell density-dependent since the distinct phenomena were lost when cell density was increased. ONAS modulated cytoskeletal reorganization and inhibited formation of focal adhesion, which is generally observed in NSCs grown on flat surfaces. ONAS appeared to reinforce NSC-NSC interaction, restricted individual cell migration and prohibited NSC attachment to the nanopore surface. These data demonstrate that ONAS maintains NSCs as undifferentiated while retaining multipotency and is a better topography for culturing low density NSCs.

Key role of dual specificity kinase TTK in proliferation and survival of pancreatic cancer cells

PubMed Central

Kaistha, B P; Honstein, T; Müller, V; Bielak, S; Sauer, M; Kreider, R; Fassan, M; Scarpa, A; Schmees, C; Volkmer, H; Gress, T M; Buchholz, M

2014-01-01

Background: Pancreatic ductal adenocarcinoma (PDAC) is among the most aggressive human malignancies with an overall 5-year survival rate of <5%. Despite significant advances in treatment of the disease during the past decade, the median survival rate (∼6 months) has hardly improved, warranting the need to identify novel targets for therapeutic approaches. Methods: Quantitative real time PCR, western blot analyses and immunohistochemical staining of tissue microarrays were used to analyse the expression of TTK gene in primary PDAC tissues and cell lines. To inhibit TTK kinase expression in a variety of pancreatic cancer cell lines, RNA interference was used. Functional roles of this kinase in the context of PDAC were studied using cell proliferation, viability and anchorage-independent growth assays. Western blotting, fluorescence-activated cell sorting analyses and fluorescence microscopy were used to gain mechanistic insight into the functional effects. Conclusions: We show that the dual specificity kinase TTK (also known as Mps1), is strongly overexpressed in human PDAC. Functionally, cell proliferation was significantly attenuated following TTK knockdown, whereas apoptosis and necrosis rates were significantly increased. In addition, anchorage-independent growth, a hallmark of malignant transformation and metastatic potential, was strongly impaired in the absence of TTK gene function. Interestingly, immortalised normal pancreatic hTERT-HPNE cells were not affected by loss of TTK function. Mechanistically, these effects in cancer cells were associated with increased formation of micronuclei, suggesting that loss of TTK function in pancreatic cancer cells results in chromosomal instability and mitotic catastrophe. Taken together, our data show that TTK function is critical for growth and proliferation of pancreatic cancer cells, thus establishing this kinase as an interesting new target for novel therapeutic approaches in combating this malignancy. PMID:25137017

Sexually Dimorphic Patterns of Cell Proliferation in the Brain Are Linked to Seasonal Life-History Transitions in Red-Sided Garter Snakes.

PubMed

Lutterschmidt, Deborah I; Lucas, Ashley R; Karam, Ritta A; Nguyen, Vicky T; Rasmussen, Meghann R

2018-01-01

Seasonal rhythms in physiology and behavior are widespread across diverse taxonomic groups and may be mediated by seasonal changes in neurogenesis, including cell proliferation, migration, and differentiation. We examined if cell proliferation in the brain is associated with the seasonal life-history transition from spring breeding to migration and summer foraging in a free-ranging population of red-sided garter snakes ( Thamnophis sirtalis ) in Manitoba, Canada. We used the thymidine analog 5-bromo-2'-deoxyuridine (BrdU) to label newly proliferated cells within the brain of adult snakes collected from the den during the mating season or from a road located along their migratory route. To assess rates of cell migration, we further categorized BrdU-labeled cells according to their location within the ventricular zone or parenchymal region of the nucleus sphericus (homolog of the amygdala), preoptic area/hypothalamus, septal nucleus, and cortex (homolog of the hippocampus). We found that cell proliferation and cell migration varied significantly with sex, the migratory status of snakes, and reproductive behavior in males. In most regions of interest, patterns of cell proliferation were sexually dimorphic, with males having significantly more BrdU-labeled cells than females prior to migration. However, during the initial stages of migration, females exhibited a significant increase in cell proliferation within the nucleus sphericus, hypothalamus, and septal nucleus, but not in any subregion of the cortex. In contrast, migrating males exhibited a significant increase in cell proliferation within the medial cortex but no other brain region. Because it is unlikely that the medial cortex plays a sexually dimorphic role in spatial memory during spring migration, we speculate that cell proliferation within the male medial cortex is associated with regulation of the hypothalamus-pituitary-adrenal axis. Finally, the only brain region where cell migration into the parenchymal region varied significantly with sex or migratory status was the hypothalamus. These results suggest that the migration of newly proliferated cells and/or the continued division of undifferentiated cells are activated earlier or to a greater extent in the hypothalamus. Our data suggest that sexually dimorphic changes in cell proliferation and cell migration in the adult brain may mediate sex differences in the timing of seasonal life-history transitions.

Sexually Dimorphic Patterns of Cell Proliferation in the Brain Are Linked to Seasonal Life-History Transitions in Red-Sided Garter Snakes

PubMed Central

Lutterschmidt, Deborah I.; Lucas, Ashley R.; Karam, Ritta A.; Nguyen, Vicky T.; Rasmussen, Meghann R.

2018-01-01

Seasonal rhythms in physiology and behavior are widespread across diverse taxonomic groups and may be mediated by seasonal changes in neurogenesis, including cell proliferation, migration, and differentiation. We examined if cell proliferation in the brain is associated with the seasonal life-history transition from spring breeding to migration and summer foraging in a free-ranging population of red-sided garter snakes (Thamnophis sirtalis) in Manitoba, Canada. We used the thymidine analog 5-bromo-2′-deoxyuridine (BrdU) to label newly proliferated cells within the brain of adult snakes collected from the den during the mating season or from a road located along their migratory route. To assess rates of cell migration, we further categorized BrdU-labeled cells according to their location within the ventricular zone or parenchymal region of the nucleus sphericus (homolog of the amygdala), preoptic area/hypothalamus, septal nucleus, and cortex (homolog of the hippocampus). We found that cell proliferation and cell migration varied significantly with sex, the migratory status of snakes, and reproductive behavior in males. In most regions of interest, patterns of cell proliferation were sexually dimorphic, with males having significantly more BrdU-labeled cells than females prior to migration. However, during the initial stages of migration, females exhibited a significant increase in cell proliferation within the nucleus sphericus, hypothalamus, and septal nucleus, but not in any subregion of the cortex. In contrast, migrating males exhibited a significant increase in cell proliferation within the medial cortex but no other brain region. Because it is unlikely that the medial cortex plays a sexually dimorphic role in spatial memory during spring migration, we speculate that cell proliferation within the male medial cortex is associated with regulation of the hypothalamus-pituitary-adrenal axis. Finally, the only brain region where cell migration into the parenchymal region varied significantly with sex or migratory status was the hypothalamus. These results suggest that the migration of newly proliferated cells and/or the continued division of undifferentiated cells are activated earlier or to a greater extent in the hypothalamus. Our data suggest that sexually dimorphic changes in cell proliferation and cell migration in the adult brain may mediate sex differences in the timing of seasonal life-history transitions.

Nanocarbon Allotropes-Graphene and Nanocrystalline Diamond-Promote Cell Proliferation.

PubMed

Verdanova, Martina; Rezek, Bohuslav; Broz, Antonin; Ukraintsev, Egor; Babchenko, Oleg; Artemenko, Anna; Izak, Tibor; Kromka, Alexander; Kalbac, Martin; Hubalek Kalbacova, Marie

2016-05-01

Two profoundly different carbon allotropes - nanocrystalline diamond and graphene - are of considerable interest from the viewpoint of a wide range of biomedical applications including implant coating, drug and gene delivery, cancer therapy, and biosensing. Osteoblast adhesion and proliferation on nanocrystalline diamond and graphene are compared under various conditions such as differences in wettability, topography, and the presence or absence of protein interlayers between cells and the substrate. The materials are characterized in detail by means of scanning electron microscopy, atomic force microscopy, photoelectron spectroscopy, Raman spectroscopy, and contact angle measurements. In vitro experiments have revealed a significantly higher degree of cell proliferation on graphene than on nanocrystalline diamond and a tissue culture polystyrene control material. Proliferation is promoted, in particular, by hydrophobic graphene with a large number of nanoscale wrinkles independent of the presence of a protein interlayer, i.e., substrate fouling is not a problematic issue in this respect. Nanowrinkled hydrophobic graphene, thus, exhibits superior characteristics for those biomedical applications where high cell proliferation is required under differing conditions. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Leptin reverses corticosterone-induced inhibition of neural stem cell proliferation through activating the NR2B subunits of NMDA receptors

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

Shi, Wen-Zhu; Anesthesia and Operation Center, Chinese PLA General Hospital, Beijing 100853; Miao, Yu-Liang

Highlights: • Leptin promotes the proliferation of neural stem cells isolated from embryonic mouse hippocampus. • Leptin reverses corticosterone-induced inhibition of neural stem cell proliferation. • The effects of leptin are partially mediated by upregulating NR2B subunits. - Abstract: Corticosterone inhibits the proliferation of hippocampal neural stem cells (NSCs). The removal of corticosterone-induced inhibition of NSCs proliferation has been reported to contribute to neural regeneration. Leptin has been shown to regulate brain development, improve angiogenesis, and promote neural regeneration; however, its effects on corticosterone-induced inhibition of NSCs proliferation remain unclear. Here we reported that leptin significantly promoted the proliferation ofmore » hippocampal NSCs in a concentration-dependent pattern. Also, leptin efficiently reversed the inhibition of NSCs proliferation induced by corticosterone. Interestingly, pre-treatment with non-specific NMDA antagonist MK-801, specific NR2B antagonist Ro 25-6981, or small interfering RNA (siRNA) targeting NR2B, significantly blocked the effect of leptin on corticosterone-induced inhibition of NSCs proliferation. Furthermore, corticosterone significantly reduced the protein expression of NR2B, whereas pre-treatment with leptin greatly reversed the attenuation of NR2B expression caused by corticosterone in cultured hippocampal NSCs. Our findings demonstrate that leptin reverses the corticosterone-induced inhibition of NSCs proliferation. This process is, at least partially mediated by increased expression of NR2B subunits of NMDA receptors.« less

Correlation of circular RNA abundance with proliferation--exemplified with colorectal and ovarian cancer, idiopathic lung fibrosis, and normal human tissues.

PubMed

Bachmayr-Heyda, Anna; Reiner, Agnes T; Auer, Katharina; Sukhbaatar, Nyamdelger; Aust, Stefanie; Bachleitner-Hofmann, Thomas; Mesteri, Ildiko; Grunt, Thomas W; Zeillinger, Robert; Pils, Dietmar

2015-01-27

Circular RNAs are a recently (re-)discovered abundant RNA species with presumed function as miRNA sponges, thus part of the competing endogenous RNA network. We analysed the expression of circular and linear RNAs and proliferation in matched normal colon mucosa and tumour tissues. We predicted >1,800 circular RNAs and proved the existence of five randomly chosen examples using RT-qPCR. Interestingly, the ratio of circular to linear RNA isoforms was always lower in tumour compared to normal colon samples and even lower in colorectal cancer cell lines. Furthermore, this ratio correlated negatively with the proliferation index. The correlation of global circular RNA abundance (the circRNA index) and proliferation was validated in a non-cancerous proliferative disease, idiopathic pulmonary fibrosis, ovarian cancer cells compared to cultured normal ovarian epithelial cells, and 13 normal human tissues. We are the first to report a global reduction of circular RNA abundance in colorectal cancer cell lines and cancer compared to normal tissues and discovered a negative correlation of global circular RNA abundance and proliferation. This negative correlation seems to be a general principle in human tissues as validated with three different settings. Finally, we present a simple model how circular RNAs could accumulate in non-proliferating cells.

A simple method to assess in vivo proliferation in lung vasculature with EdU: the case of MMC-induced PVOD in rat.

PubMed

Fabrice, Antigny; Benoît, Ranchoux; Valérie, Nadeau; Lau, Edmund; Sébastien, Bonnet; Frédéric, Perros

2015-01-01

5-Ethynyl-2'-deoxyuridine (EdU) incorporation is becoming the gold standard method for in vitro and in vivo visualization of proliferating cells. The small size of the fluorescent azides used for detection results in a high degree of specimen penetration. It can be used to easily detect DNA replication in large tissue samples or organ explants with low proliferation and turnover of cells formerly believed to be in a "terminal" state of differentiation. Here we describe a protocol for the localization and identification of proliferating cells in quiescent or injured pulmonary vasculature, in a model of pulmonary veno-occlusive disease (PVOD). PVOD is an uncommon form of pulmonary hypertension characterized by progressive obstruction of small pulmonary veins. We previously reported that mitomycin-C (MMC) therapy is associated with PVOD in human. We demonstrated that MMC can induce PVOD in rats, which currently represents the sole animal model that recapitulates human PVOD lesions. Using the EdU assay, we demonstrated that MMC-exposed lungs displayed areas of exuberant microvascular endothelial cell proliferation which mimics pulmonary capillary hemangiomatosis, one of the pathologic hallmarks of human PVOD. In vivo pulmonary cell proliferation measurement represents an interesting methodology to investigate the potential efficacy of therapies aimed at normalizing pathologic angioproliferation.

Correlation of circular RNA abundance with proliferation – exemplified with colorectal and ovarian cancer, idiopathic lung fibrosis, and normal human tissues

PubMed Central

Bachmayr-Heyda, Anna; Reiner, Agnes T.; Auer, Katharina; Sukhbaatar, Nyamdelger; Aust, Stefanie; Bachleitner-Hofmann, Thomas; Mesteri, Ildiko; Grunt, Thomas W.; Zeillinger, Robert; Pils, Dietmar

2015-01-01

Circular RNAs are a recently (re-)discovered abundant RNA species with presumed function as miRNA sponges, thus part of the competing endogenous RNA network. We analysed the expression of circular and linear RNAs and proliferation in matched normal colon mucosa and tumour tissues. We predicted >1,800 circular RNAs and proved the existence of five randomly chosen examples using RT-qPCR. Interestingly, the ratio of circular to linear RNA isoforms was always lower in tumour compared to normal colon samples and even lower in colorectal cancer cell lines. Furthermore, this ratio correlated negatively with the proliferation index. The correlation of global circular RNA abundance (the circRNA index) and proliferation was validated in a non-cancerous proliferative disease, idiopathic pulmonary fibrosis, ovarian cancer cells compared to cultured normal ovarian epithelial cells, and 13 normal human tissues. We are the first to report a global reduction of circular RNA abundance in colorectal cancer cell lines and cancer compared to normal tissues and discovered a negative correlation of global circular RNA abundance and proliferation. This negative correlation seems to be a general principle in human tissues as validated with three different settings. Finally, we present a simple model how circular RNAs could accumulate in non-proliferating cells. PMID:25624062

Hepatocyte-specific PPARA expression exclusively promotes agonist-induced cell proliferation without influence from nonparenchymal cells

PubMed Central

Brocker, Chad N.; Yue, Jiang; Kim, Donghwan; Qu, Aijuan; Bonzo, Jessica A.

2017-01-01

Peroxisome proliferator-activated receptor-α (PPARA) is a nuclear transcription factor and key mediator of systemic lipid metabolism. Prolonged activation in rodents causes hepatocyte proliferation and hepatocellular carcinoma. Little is known about the contribution of nonparenchymal cells (NPCs) to PPARA-mediated cell proliferation. NPC contribution to PPARA agonist-induced hepatomegaly was assessed in hepatocyte (Ppara△Hep)- and macrophage (Ppara△Mac)-specific Ppara null mice. Mice were treated with the agonist Wy-14643 for 14 days, and response of conditional null mice was compared with conventional knockout mice (Ppara−/−). Wy-14643 treatment caused weight loss and severe hepatomegaly in wild-type and Ppara△Mac mice, and histological analysis revealed characteristic hepatocyte swelling; Ppara△Hep and Ppara−/− mice were protected from these effects. Ppara△Mac serum chemistries, as well as aspartate aminotransferase and alanine aminotransferase levels, matched wild-type mice. Agonist-treated Ppara△Hep mice had elevated serum cholesterol, phospholipids, and triglycerides when compared with Ppara−/− mice, indicating a possible role for extrahepatic PPARA in regulating circulating lipid levels. BrdU labeling confirmed increased cell proliferation only in wild-type and Ppara△Mac mice. Macrophage PPARA disruption did not impact agonist-induced upregulation of lipid metabolism, cell proliferation, or DNA damage and repair-related gene expression, whereas gene expression was repressed in Ppara△Hep mice. Interestingly, downregulation of inflammatory cytokines IL-15 and IL-18 was dependent on macrophage PPARA. Cell type-specific regulation of target genes was confirmed in primary hepatocytes and Kupffer cells. These studies conclusively show that cell proliferation is mediated exclusively by PPARA activation in hepatocytes and that Kupffer cell PPARA has an important role in mediating the anti-inflammatory effects of PPARA agonists. PMID:28082284

MAPK1 is required for establishing the pattern of cell proliferation and for cell survival during lens development

PubMed Central

Upadhya, Dinesh; Ogata, Masato; Reneker, Lixing W.

2013-01-01

The mitogen-activated protein kinases (MAPKs; also known as ERKs) are key intracellular signaling molecules that are ubiquitously expressed in tissues and were assumed to be functionally equivalent. Here, we use the mouse lens as a model system to investigate whether MAPK1 plays a specific role during development. MAPK3 is known to be dispensable for lens development. We demonstrate that, although MAPK1 is uniformly expressed in the lens epithelium, its deletion significantly reduces cell proliferation in the peripheral region, an area referred to as the lens germinative zone in which most active cell division occurs during normal lens development. By contrast, cell proliferation in the central region is minimally affected by MAPK1 deletion. Cell cycle regulators, including cyclin D1 and survivin, are downregulated in the germinative zone of the MAPK1-deficient lens. Interestingly, loss of MAPK1 subsequently induces upregulation of phosphorylated MAPK3 (pMAPK3) levels in the lens epithelium; however, this increase in pMAPK3 is not sufficient to restore cell proliferation in the germinative zone. Additionally, MAPK1 plays an essential role in epithelial cell survival but is dispensable for fiber cell differentiation during lens development. Our data indicate that MAPK1/3 control cell proliferation in the lens epithelium in a spatially defined manner; MAPK1 plays a unique role in establishing the highly mitotic zone in the peripheral region, whereas the two MAPKs share a redundant role in controlling cell proliferation in the central region of the lens epithelium. PMID:23482492

Wnt5a-Ror2 signaling in mesenchymal stem cells promotes proliferation of gastric cancer cells by activating CXCL16-CXCR6 axis.

PubMed

Takiguchi, Gosuke; Nishita, Michiru; Kurita, Kana; Kakeji, Yoshihiro; Minami, Yasuhiro

2016-03-01

Wnt5a-Ror2 signaling has been shown to play important roles in promoting aggressiveness of various cancer cells in a cell-autonomous manner. However, little is known about its function in cancer-associated stromal cells, including mesenchymal stem cells (MSCs). Thus, we examined the role of Wnt5a-Ror2 signaling in bone marrow-derived MSCs in regulating proliferation of undifferentiated gastric cancer cells. Coculture of a gastric cancer cell line, MKN45, with MSCs either directly or indirectly promotes proliferation of MKN45 cells, and suppressed expression of Ror2 in MSCs prior to coculture inhibits enhanced proliferation of MKN45 cells. In addition, conditioned media from MSCs, treated with control siRNA, but not siRNAs against Ror2, can enhance proliferation of MKN45 cells. Interestingly, it was found that expression of CXCL16 in MSCs is augmented by Wnt5a-Ror2 signaling, and that recombinant chemokine (C-X-C motif) ligand (CXCL)16 protein can enhance proliferation of MKN45 cells in the absence of MSCs. In fact, suppressed expression of CXCL16 in MSCs or an addition of a neutralizing antibody against CXCL16 fails to promote proliferation of MKN45 cells in either direct or indirect coculture with MSCs. Importantly, we show that MKN45 cells express chemokine (C-X-C motif) receptor (CXCR)6, a receptor for CXCL16, and that suppressed expression of CXCR6 in MKN45 cells results in a failure of its enhanced proliferation in either direct or indirect coculture with MSCs. These findings indicate that Wnt5a-Ror2 signaling enhances expression of CXCL16 in MSCs and, as a result, enhanced secretion of CXCL16 from MSCs might act on CXCR6 expressed on MKN45, leading to the promotion of its proliferation. © 2015 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

COX-2/mPGES-1/PGE2 cascade activation mediates uric acid-induced mesangial cell proliferation.

PubMed

Li, Shuzhen; Sun, Zhenzhen; Zhang, Yue; Ruan, Yuan; Chen, Qiuxia; Gong, Wei; Yu, Jing; Xia, Weiwei; He, John Ci-Jiang; Huang, Songming; Zhang, Aihua; Ding, Guixia; Jia, Zhanjun

2017-02-07

Hyperuricemia is not only the main feature of gout but also a cause of gout-related organ injuries including glomerular hypertrophy and sclerosis. Uric acid (UA) has been proven to directly cause mesangial cell (MC) proliferation with elusive mechanisms. The present study was undertaken to examined the role of inflammatory cascade of COX-2/mPGES-1/PGE2 in UA-induced MC proliferation. In the dose- and time-dependent experiments, UA increased cell proliferation shown by the increased total cell number, DNA synthesis rate, and the number of cells in S and G2 phases in parallel with the upregulation of cyclin A2 and cyclin D1. Interestingly, UA-induced cell proliferation was accompanied with the upregulation of COX-2 and mPGES-1 at both mRNA and protein levels. Strikingly, inhibition of COX-2 via a specific COX-2 inhibitor NS-398 markedly blocked UA-induced MC proliferation. Meanwhile, UA-induced PGE2 production was almost entirely abolished. Furthermore, inhibiting mPGES-1 by a siRNA approach in MCs also ameliorated UA-induced MC proliferation in line with a significant blockade of PGE2 secretion. More importantly, in gout patients, we observed a significant elevation of urinary PGE2 excretion compared with healthy controls, indicating a translational potential of this study to the clinic. In conclusion, our findings indicated that COX-2/mPGES-1/PGE2 cascade activation mediated UA-induced MC proliferation. This study offered new insights into the understanding and the intervention of UA-related glomerular injury.

Expression of WNT genes in cervical cancer-derived cells: Implication of WNT7A in cell proliferation and migration.

PubMed

Ramos-Solano, Moisés; Meza-Canales, Ivan D; Torres-Reyes, Luis A; Alvarez-Zavala, Monserrat; Alvarado-Ruíz, Liliana; Rincon-Orozco, Bladimiro; Garcia-Chagollan, Mariel; Ochoa-Hernández, Alejandra B; Ortiz-Lazareno, Pablo C; Rösl, Frank; Gariglio, Patricio; Jave-Suárez, Luis F; Aguilar-Lemarroy, Adriana

2015-07-01

According to the multifactorial model of cervical cancer (CC) causation, it is now recognized that other modifications, in addition to Human papillomavirus (HPV) infection, are necessary for the development of this neoplasia. Among these, it has been proposed that a dysregulation of the WNT pathway might favor malignant progression of HPV-immortalized keratinocytes. The aim of this study was to identify components of the WNT pathway differentially expressed in CC vs. non-tumorigenic, but immortalized human keratinocytes. Interestingly, WNT7A expression was found strongly downregulated in cell lines and biopsies derived from CC. Restoration of WNT7A in CC-derived cell lines using a lentiviral gene delivery system or after adding a recombinant human protein decreases cell proliferation. Likewise, WNT7A silencing in non-tumorigenic cells markedly accelerates proliferation. Decreased WNT7A expression was due to hypermethylation at particular CpG sites. To our knowledge, this is the first study reporting reduced WNT7A levels in CC-derived cells and that ectopic WNT7A restoration negatively affects cell proliferation and migration. Copyright © 2015 Elsevier Inc. All rights reserved.

Tissue kallikrein induces SH-SY5Y cell proliferation via epidermal growth factor receptor and extracellular signal-regulated kinase1/2 pathway

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

Lu, Zhengyu; Department of Neurology, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 200437; Yang, Qi

2014-03-28

Highlights: • TK promotes EGFR phosphorylation in SH-SY5Y cells. • TK activates ERK1/2 and p38 phosphorylation in SH-SY5Y cells. • TK mediates SH-SY5Y cell proliferation via EGFR and ERK1/2 pathway. - Abstract: Tissue kallikrein (TK) is well known to take most of its biological functions through bradykinin receptors. In the present study, we found a novel signaling pathway mediated by TK through epidermal growth factor receptor (EGFR) in human SH-SY5Y cells. We discovered that TK facilitated the activation of EGFR, extracellular signal-regulated kinase (ERK) 1/2 and p38 cascade. Interestingly, not p38 but ERK1/2 phosphorylation was severely compromised in cells depletedmore » of EGFR. Nevertheless, impairment of signaling of ERK1/2 seemed not to be restricted to EGFR phosphorylation. We also observed that TK stimulation could induce SH-SY5Y cell proliferation, which was reduced by EGFR down-regulation or ERK1/2 inhibitor. Overall, our findings provided convincing evidence that TK could mediate cell proliferation via EGFR and ERK1/2 pathway in vitro.« less

Influence of oxygen concentration on T cell proliferation and susceptibility to apoptosis in healthy men and women.

PubMed

Waskowska, Agnieszka; Lisowska, Katarzyna A; Daca, Agnieszka; Henc, Izabella; Brandberg, Fredrik; Mazurek, Paula; Brzustewicz, Edyta; Witkowski, Jacek M; Bryl, Ewa

2017-01-01

Much of what we know about the functioning of human T lymphocytes is based on the experiments carried out in atmospheric oxygen (O₂) concentrations, which are significantly higher than those maintained in blood. Interestingly, the gender differences in the activity of T cells and their susceptibility to apoptosis under different O₂ conditions have not yet been described. The aim of the study was to compare two main markers of lymphocyte function: proliferation capacity and ability to produce cytokines as well as their susceptibility to apoptosis under two different O₂ concentrations, between men and women. 25 healthy volunteers, both males (13) and females (12) were recruited to the study (mean age 25.48 ± 5.51). By using cytometry proliferation parameters of human CD4+ CD28+ cells or CD8+CD28+ cells in response to polyclonal stimulation of the TCR/CD3 complex at atmospheric (21%) and physiological (10%) O₂ concentrations using our modified dividing cell tracking technique (DCT) were analyzed as well as the percentages of apoptotic cells. We also determined the levels of IFN-γ, IL-2, IL-10 and IL-17A using Cytometric Bead Array Flex system in cell culture supernatants. CD4+CD28+ and CD8+CD28+ cells from the whole study group were characterized by shorter time required to enter the first (G1) phase of the first cell cycle at 21% compared to 10% O₂. Both T cell populations performed significantly more divisions at 21% O₂. The percentages of dividing cells were also significantly higher at atmospheric O₂. Interestingly, data analysis by gender showed that male lymphocytes had similar proliferative parameters at both O₂ concentrations while female lymphocytes proliferate more efficiently (note from the author: we cannot say that lymphocytes proliferate faster, rather more effectively, because cells perform more divisions, which gives more percentage of offspring cells) at 21% oxygen. Compared to males, the female CD4+ cells showed increased susceptibility to apoptosis at both O₂ concentrations. No differences in the levels of cytokines regardless of gender and oxygen conditions were found. We showed that in vitro female T cells (both CD4+ and CD8+ cells) are more sensitive than male lymphocytes to low O2 concentration as demonstrated by the decrease in their proliferation dynamics. The effect does not depend on increased apoptosis of female T cells under low O₂ because percentage of apoptotic cells was similar at both O₂ concentrations.

Usage of Human Mesenchymal Stem Cells in Cell-based Therapy: Advantages and Disadvantages.

PubMed

Kim, Hee Jung; Park, Jeong-Soo

2017-03-01

The use of human mesenchymal stem cells (hMSCs) in cell-based therapy has attracted extensive interest in the field of regenerative medicine, and it shows applications to numerous incurable diseases. hMSCs show several superior properties for therapeutic use compared to other types of stem cells. Different cell types are discussed in terms of their advantages and disadvantages, with focus on the characteristics of hMSCs. hMSCs can proliferate readily and produce differentiated cells that can substitute for the targeted affected tissue. To maximize the therapeutic effects of hMSCs, a substantial number of these cells are essential, requiring extensive ex vivo cell expansion. However, hMSCs have a limited lifespan in an in vitro culture condition. The senescence of hMSCs is a double-edged sword from the viewpoint of clinical applications. Although their limited cell proliferation potency protects them from malignant transformation after transplantation, senescence can alter various cell functions including proliferation, differentiation, and migration, that are essential for their therapeutic efficacy. Numerous trials to overcome the limited lifespan of mesenchymal stem cells are discussed.

Usage of Human Mesenchymal Stem Cells in Cell-based Therapy: Advantages and Disadvantages

PubMed Central

Kim, Hee Jung; Park, Jeong-Soo

2017-01-01

ABSTRACT The use of human mesenchymal stem cells (hMSCs) in cell-based therapy has attracted extensive interest in the field of regenerative medicine, and it shows applications to numerous incurable diseases. hMSCs show several superior properties for therapeutic use compared to other types of stem cells. Different cell types are discussed in terms of their advantages and disadvantages, with focus on the characteristics of hMSCs. hMSCs can proliferate readily and produce differentiated cells that can substitute for the targeted affected tissue. To maximize the therapeutic effects of hMSCs, a substantial number of these cells are essential, requiring extensive ex vivo cell expansion. However, hMSCs have a limited lifespan in an in vitro culture condition. The senescence of hMSCs is a double-edged sword from the viewpoint of clinical applications. Although their limited cell proliferation potency protects them from malignant transformation after transplantation, senescence can alter various cell functions including proliferation, differentiation, and migration, that are essential for their therapeutic efficacy. Numerous trials to overcome the limited lifespan of mesenchymal stem cells are discussed. PMID:28484739

Viability and proliferation of endothelial cells upon exposure to GaN nanoparticles

PubMed Central

Braniste, Tudor; Tiginyanu, Ion; Horvath, Tibor; Raevschi, Simion; Cebotari, Serghei; Lux, Marco; Haverich, Axel

2016-01-01

Summary Nanotechnology is a rapidly growing and promising field of interest in medicine; however, nanoparticle–cell interactions are not yet fully understood. The goal of this work was to examine the interaction between endothelial cells and gallium nitride (GaN) semiconductor nanoparticles. Cellular viability, adhesion, proliferation, and uptake of nanoparticles by endothelial cells were investigated. The effect of free GaN nanoparticles versus the effect of growing endothelial cells on GaN functionalized surfaces was examined. To functionalize surfaces with GaN, GaN nanoparticles were synthesized on a sacrificial layer of zinc oxide (ZnO) nanoparticles using hydride vapor phase epitaxy. The uptake of GaN nanoparticles by porcine endothelial cells was strongly dependent upon whether they were fixed to the substrate surface or free floating in the medium. The endothelial cells grown on surfaces functionalized with GaN nanoparticles demonstrated excellent adhesion and proliferation, suggesting good biocompatibility of the nanostructured GaN. PMID:27826507

Inhibition of FLT3 Expression by Green Tea Catechins in FLT3 Mutated-AML Cells

PubMed Central

Ly, Bui Thi Kim; Chi, Hoang Thanh; Yamagishi, Makoto; Kano, Yasuhiko; Hara, Yukihiko; Nakano, Kazumi; Sato, Yuko; Watanabe, Toshiki

2013-01-01

Acute myeloid leukemia (AML) is a heterogeneous disease characterized by a block in differentiation and uncontrolled proliferation. FLT3 is a commonly mutated gene found in AML patients. In clinical trials, the presence of a FLT3-ITD mutation significantly correlates with an increased risk of relapse and dismal overall survival. Therefore, activated FLT3 is a promising molecular target for AML therapies. In this study, we have shown that green tea polyphenols including (−)-epigallocatechin-3-gallate (EGCG), (−)-epigallocatechin (EGC), and (−)-epicatechin-3-gallate (ECG) suppress the proliferation of AML cells. Interestingly, EGCG, EGC and ECG showed the inhibition of FLT3 expression in cell lines harboring FLT3 mutations. In the THP-1 cells harboring FLT3 wild-type, EGCG showed the suppression of cell proliferation but did not suppress the expression of FLT3 even at the concentration that suppress 100% cell proliferation. Moreover, EGCG-, EGC-and ECG-treated cells showed the suppression of MAPK, AKT and STAT5 phosphorylation. Altogether, we suggest that green tea polyphenols could serve as reagents for treatment or prevention of leukemia harboring FLT3 mutations. PMID:23840454

p21, an important mediator of quiescence during pituitary tumor formation, is dispensable for normal pituitary development during embryogenesis.

PubMed Central

Monahan, Pamela; Himes, Ashley D.; Parfieniuk, Agata; Raetzman, Lori T.

2011-01-01

A delicate balance between proliferation and differentiation must be maintained in the developing pituitary to ensure the formation of the appropriate number of hormone producing cells. In the adult, proliferation is actively restrained to prevent tumor formation. The cyclin dependent kinase inhibitors (CDKIs) of the CIP/KIP family, p21, p27 and p57, mediate cell cycle inhibition. Although p21 is induced in the pituitary upon loss of Notch signaling or initiation of tumor formation to halt cell cycle progression, its role in normal pituitary organogenesis has not been explored. In wildtype pituitaries, expression of p21 is limited to a subset of cells embryonically as well as during the postnatal proliferative phase. Mice lacking p21 do not have altered cell proliferation during early embryogenesis, but do show a slight delay in separation of proliferating progenitors from the oral ectoderm. By embryonic day 16.5, p21 mutants have an alteration in the spatial distribution of proliferating pituitary progenitors, however there is no overall change in proliferation. At postnatal day 21, there appears to be no change in proliferation, as assessed by cells expressing Ki67 protein. However, p21 mutant pituitaries have significantly less mRNA of Myc and the cyclins Ccnb1, Ccnd1, Ccnd2 and Ccne1 than wildtype pituitaries. Interestingly, unlike the redundant role in cell cycle inhibition uncovered in p27/p57 double mutants, the pituitary of p21/p27 double mutants has a similar proliferation profile to p27 single mutants at the time points examined. Taken together, these studies demonstrate that unlike p27 or p57, p21 does not play a major role in control of progenitor proliferation in the developing pituitary. However, p21 may be required to maintain normal levels of cell cycle components. PMID:22154697

Dixdc1 targets CyclinD1 and p21 via PI3K pathway activation to promote Schwann cell proliferation after sciatic nerve crush

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

Wu, Weijie; Liu, Qingqing; Liu, Yuxi

Dixdc1 (DIX domain containing-1), the mammalian homolog of Ccd1 (Coiled-coil-Dishevelled-Axin1), is a protein containing a coiled-coil domain and a Dishevelled-Axin (DIX) domain. As a novel component of the Wnt pathway, Dixdc1 has been reported to be able to promote neural progenitor proliferation and neuronal differentiation via Wnt/β-catenin signaling. But there still remains something unknown about Dixdc1 distribution and functions in the lesion and regeneration of the peripheral nervous system (PNS), so we tried to investigate dynamic changes of Dixdc1 expression in a rat sciatic nerve crush (SNC) model in this study. First of all, we detected SNC-induced increased levels ofmore » Dixdc1 in Schwann cells and interestingly identified parallel expression of PCNA (proliferation cell nuclear antigen) with Dixdc1. Besides, we observed up-regulated Dixdc1 during the process of TNF-α-induced Schwann cell proliferation. Also, we discovered that Dixdc1 could promote G1-S phase transition accompanied with the up-regulation of CyclinD1 and down-regulation of p21. More importantly, enhanced effects of Dixdc1 on cell proliferation were confirmed to be associated with PI3K activation. Not only blocking of the PI3K but Dixdc1 knockdown led to significantly decreased ability for proliferation, as well as down-regulation of CyclinD1 and up-regulation of p21. In summary, these data demonstrated that Dixdc1 might participate in Schwann cell proliferation by targeting CyclinD1 and p21 at least partially through the PI3K/AKT activation. - Highlights: • The dynamic changes and location of Dixdc1 after sciatic nerve crush. • Dixdc1 was associated with Schwann cell proliferation. • Dixdc1 promoted Schwann cell proliferation partly via PI3K/AKT pathway.« less

miR-1271 promotes non-small-cell lung cancer cell proliferation and invasion via targeting HOXA5

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

Wang, Yongfang; Xu, Lianhong; Jiang, Lixin, E-mail: jianglx66766@163.com

2015-03-13

MicroRNAs (miRNAs) are short, non-coding RNAs (∼22 nt) that play important roles in the pathogenesis of human diseases by negatively regulating numerous target genes at posttranscriptional level. However, the role of microRNAs in lung cancer, particularly non-small-cell lung cancer (NSCLC), has remained elusive. In this study, two microRNAs, miR-1271 and miR-628, and their predicted target genes were identified differentially expressed in NSCLC by analyzing the miRNA and mRNA expression data from NSCLC tissues and their matching normal controls. miR-1271 and its target gene HOXA5 were selected for further investigation. CCK-8 proliferation assay showed that the cell proliferation was promoted by miR-1271more » in NSCLC cells, while miR-1271 inhibitor could significantly inhibited the proliferation of NSCLC cells. Interestingly, migration and invasion assay indicated that overexpression of miR-1271 could significantly promoted the migration and invasion of NSCLC cells, whereas miR-1271 inhibitor could inhibited both cell migration and invasion of NSCLC cells. Western blot showed that miR-1271 suppressed the protein level of HOXA5, and luciferase assays confirmed that miR-1271 directly bound to the 3'untranslated region of HOXA5. This study indicated indicate that miR-1271 regulates NSCLC cell proliferation and invasion, via the down-regulation of HOXA5. Thus, miR-1271 may represent a potential therapeutic target for NSCLC intervention. - Highlights: • Overexpression of miR-1271 promoted proliferation and invasion of NSCLC cells. • miR-1271 inhibitor inhibited the proliferation and invasion of NSCLC cells. • miR-1271 targets 3′ UTR of HOXA5 in NSCLC cells. • miR-1271 negatively regulates HOXA5 in NSCLC cells.« less

The oncoprotein HBXIP upregulates PDGFB via activating transcription factor Sp1 to promote the proliferation of breast cancer cells

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

Zhang, Yingyi; Zhao, Yu; Li, Leilei

2013-05-03

Highlights: •HBXIP is able to upregulate the expression of PDGFB in breast cancer cells. •HBXIP serves as a coactivator of activating transcription factor Sp1. •HBXIP stimulates the PDGFB promoter via activating transcription factor Sp1. •HBXIP promotes the proliferation of breast cancer cell via upregulating PDGFB. -- Abstract: We have reported that the oncoprotein hepatitis B virus X-interacting protein (HBXIP) acts as a novel transcriptional coactivator to promote proliferation and migration of breast cancer cells. Previously, we showed that HBXIP was able to activate nuclear factor-κB (NF-κB) in breast cancer cells. As an oncogene, the platelet-derived growth factor beta polypeptide (PDGFB)more » plays crucial roles in carcinogenesis. In the present study, we found that both HBXIP and PDGFB were highly expressed in breast cancer cell lines. Interestingly, HBXIP was able to increase transcriptional activity of NF-κB through PDGFB, suggesting that HBXIP is associated with PDGFB in the cells. Moreover, HBXIP was able to upregulate PDGFB at the levels of mRNA, protein and promoter in the cells. Then, we identified that HBXIP stimulated the promoter of PDGFB through activating transcription factor Sp1. In function, HBXIP enhanced the proliferation of breast cancer cells through PDGFB in vitro. Thus, we conclude that HBXIP upregulates PDGFB via activating transcription factor Sp1 to promote proliferation of breast cancer cells.« less

Amino Acid Transport Associated to Cluster of Differentiation 98 Heavy Chain (CD98hc) Is at the Cross-road of Oxidative Stress and Amino Acid Availability.

PubMed

de la Ballina, Laura R; Cano-Crespo, Sara; González-Muñoz, Elena; Bial, Susanna; Estrach, Soline; Cailleteau, Laurence; Tissot, Floriane; Daniel, Hannelore; Zorzano, Antonio; Ginsberg, Mark H; Palacín, Manuel; Féral, Chloé C

2016-04-29

CD98hc functions as an amino acid (AA) transporter (together with another subunit) and integrin signaling enhancer. It is overexpressed in highly proliferative cells in both physiological and pathological conditions. CD98hc deletion induces strong impairment of cell proliferation in vivo and in vitro Here, we investigate CD98hc-associated AA transport in cell survival and proliferation. By using chimeric versions of CD98hc, the two functions of the protein can be uncoupled. Although recovering the CD98hc AA transport capacity restores the in vivo and in vitro proliferation of CD98hc-null cells, reconstitution of the integrin signaling function of CD98hc is unable to restore in vitro proliferation of those cells. CD98hc-associated transporters (i.e. xCT, LAT1, and y(+)LAT2 in wild-type cells) are crucial to control reactive oxygen species and intracellular AA levels, thus sustaining cell survival and proliferation. Moreover, in CD98hc-null cells the deficiency of CD98hc/xCT cannot be compensated, leading to cell death by ferroptosis. Supplementation of culture media with β-mercaptoethanol rescues CD98hc-deficient cell survival. Under such conditions null cells show oxidative stress and intracellular AA imbalance and, consequently, limited proliferation. CD98hc-null cells also present reduced intracellular levels of branched-chain and aromatic amino acids (BCAAs and ARO AAs, respectively) and induced expression of peptide transporter 1 (PEPT1). Interestingly, external supply of dipeptides containing BCAAs and ARO AAs rescues cell proliferation and compensates for impaired uptake of CD98hc/LAT1 and CD98hc/y(+)LAT2. Our data establish CD98hc as a master protective gene at the cross-road of redox control and AA availability, making it a relevant therapeutic target in cancer. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Quiescence does not affect p53 and stress response by irradiation in human lung fibroblasts

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

Dai, Jiawen; Itahana, Koji, E-mail: koji.itahana@duke-nus.edu.sg; Baskar, Rajamanickam, E-mail: r.baskar@nccs.com.sg

Cells in many organs exist in both proliferating and quiescent states. Proliferating cells are more radio-sensitive, DNA damage pathways including p53 pathway are activated to undergo either G{sub 1}/S or G{sub 2}/M arrest to avoid entering S and M phase with DNA damage. On the other hand, quiescent cells are already arrested in G{sub 0}, therefore there may be fundamental difference of irradiation response between proliferating and quiescent cells, and this difference may affect their radiosensitivity. To understand these differences, proliferating and quiescent human normal lung fibroblasts were exposed to 0.10–1 Gy of γ-radiation. The response of key proteins involvedmore » in the cell cycle, cell death, and metabolism as well as histone H2AX phosphorylation were examined. Interestingly, p53 and p53 phosphorylation (Ser-15), as well as the cyclin-dependent kinase inhibitors p21 and p27, were induced similarly in both proliferating and quiescent cells after irradiation. Furthermore, the p53 protein half-life, and expression of cyclin A, cyclin E, proliferating cell nuclear antigen (PCNA), Bax, or cytochrome c expression as well as histone H2AX phosphorylation were comparable after irradiation in both phases of cells. The effect of radioprotection by a glycogen synthase kinase 3β inhibitor on p53 pathway was also similar between proliferating and quiescent cells. Our results showed that quiescence does not affect irradiation response of key proteins involved in stress and DNA damage at least in normal fibroblasts, providing a better understanding of the radiation response in quiescent cells, which is crucial for tissue repair and regeneration. - Highlights: • p53 response by irradiation was similar between proliferating and quiescent cells. • Quiescent cells showed similar profiles of cell cycle proteins after irradiation. • Radioprotection of GSK-3β inhibitor caused similar effects between these cells. • Quiescence did not affect p53 response despite its known role in radio-resistance.« less

Systematic Analysis of Cell Cycle Effects of Common Drugs Leads to the Discovery of a Suppressive Interaction between Gemfibrozil and Fluoxetine

PubMed Central

Hoose, Scott A.; Duran, Camille; Malik, Indranil; Eslamfam, Shabnam; Shasserre, Samantha C.; Downing, S. Sabina; Hoover, Evelyn M.; Dowd, Katherine E.; Smith, Roger; Polymenis, Michael

2012-01-01

Screening chemical libraries to identify compounds that affect overall cell proliferation is common. However, in most cases, it is not known whether the compounds tested alter the timing of particular cell cycle transitions. Here, we evaluated an FDA-approved drug library to identify pharmaceuticals that alter cell cycle progression in yeast, using DNA content measurements by flow cytometry. This approach revealed strong cell cycle effects of several commonly used pharmaceuticals. We show that the antilipemic gemfibrozil delays initiation of DNA replication, while cells treated with the antidepressant fluoxetine severely delay progression through mitosis. Based on their effects on cell cycle progression, we also examined cell proliferation in the presence of both compounds. We discovered a strong suppressive interaction between gemfibrozil and fluoxetine. Combinations of interest among diverse pharmaceuticals are difficult to identify, due to the daunting number of possible combinations that must be evaluated. The novel interaction between gemfibrozil and fluoxetine suggests that identifying and combining drugs that show cell cycle effects might streamline identification of drug combinations with a pronounced impact on cell proliferation. PMID:22567160

Systematic analysis of cell cycle effects of common drugs leads to the discovery of a suppressive interaction between gemfibrozil and fluoxetine.

PubMed

Hoose, Scott A; Duran, Camille; Malik, Indranil; Eslamfam, Shabnam; Shasserre, Samantha C; Downing, S Sabina; Hoover, Evelyn M; Dowd, Katherine E; Smith, Roger; Polymenis, Michael

2012-01-01

Screening chemical libraries to identify compounds that affect overall cell proliferation is common. However, in most cases, it is not known whether the compounds tested alter the timing of particular cell cycle transitions. Here, we evaluated an FDA-approved drug library to identify pharmaceuticals that alter cell cycle progression in yeast, using DNA content measurements by flow cytometry. This approach revealed strong cell cycle effects of several commonly used pharmaceuticals. We show that the antilipemic gemfibrozil delays initiation of DNA replication, while cells treated with the antidepressant fluoxetine severely delay progression through mitosis. Based on their effects on cell cycle progression, we also examined cell proliferation in the presence of both compounds. We discovered a strong suppressive interaction between gemfibrozil and fluoxetine. Combinations of interest among diverse pharmaceuticals are difficult to identify, due to the daunting number of possible combinations that must be evaluated. The novel interaction between gemfibrozil and fluoxetine suggests that identifying and combining drugs that show cell cycle effects might streamline identification of drug combinations with a pronounced impact on cell proliferation.

Species differences in behavior and cell proliferation/survival in the adult brains of female meadow and prairie voles

PubMed Central

Pan, Yongliang; Liu, Yan; Lieberwirth, Claudia; Zhang, Zhibin; Wang, Zuoxin

2016-01-01

Microtine rodents display diverse patterns of social organization and behaviors, and thus provide a useful model for studying the effects of the social environment on physiology and behavior. The current study compared the species differences and the effects of oxytocin (OT) on anxiety-like, social affiliation, and social recognition behaviors in female meadow voles (Microtus pennsylvanicus) and prairie voles (M. ochrogaster). Furthermore, cell proliferation and survival in the brains of adult female meadow and prairie voles were compared. We found that female meadow voles displayed a higher level of anxiety-like behavior but lower levels of social affiliation and social recognition compared to female prairie voles. In addition, meadow voles showed lower levels of cell proliferation (measured by Ki67 staining) and cell survival (measured by BrdU staining) in the ventromedial hypothalamus (VMH) and amygdala (AMY), but not the dentate gyrus of the hippocampus (DG), than prairie voles. Interestingly, the numbers of new cells in the VMH and AMY, but not DG, also correlated with anxiety-like, social affiliation, and social recognition behaviors in a brain region-specific manner. Finally, central OT treatment (200 ng/kg, icv) did not lead to changes in behavior or cell proliferation/survival in the brain. Together, these data indicate a potential role of cell proliferation/survival in selected brain areas on different behaviors between vole species with distinct life strategies. PMID:26708743

Sam68 promotes Schwann cell proliferation by enhancing the PI3K/Akt pathway and acts on regeneration after sciatic nerve crush

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

Wu, Weijie, E-mail: 459586768@qq.com; Liu, Yuxi, E-mail: 924013616@qq.com; Wang, Youhua, E-mail: wyouhua1516@163.com

Sam68 (Src-associated in mitosis of 68 kD), a KH domain RNA-binding protein, is not only important in signaling transduction cascades, but crucial in a variety of cellular processes. Sam68 is reported to be involved in the phospoinositide3-kinase (PI3K) and nuclear factor-kappa B (NF-κB) signaling pathways, and it is closely associated with cell proliferation, RNA metabolism, and tumor progression. However, we know little about the role of Sam68 during peripheral nervous system injury and regeneration. In this study, we investigated the expression of Sam68 and its biological significances in sciatic nerve crush. Interestingly, we found Sam68 had a co-localization with S100 (Schwannmore » cell marker). Moreover, after crush, Sam68 had a spatiotemporal protein expression, which was in parallel with proliferation cell nuclear antigen (PCNA). In vitro, we also observed increased expression of Sam68 during the process of TNF-α-induced Schwann cell proliferation model. Besides, flow cytometry analyses, CCK-8, and EDU were all performed with the purpose of investigating the role of Sam68 in the regulation of Schwann cell proliferation. Even more importantly, we discovered that Sam68 could enhance the phosphorylation of Akt while LY294002 (a PI3K inhibitor) obviously reversed Sam68-induced cell proliferation. Finally, we detected the variance during regeneration progress through the rat walk footprint test. In summary, all these evidences demonstrated that Sam68 might participate in Schwann cell proliferation partially via PI3K/Akt pathway and also regulate regeneration after sciatic nerve crush. -- Highlights: •The dynamic changes and location of Sam68 after sciatic nerve crush. •Sam68 promoted Schwann cell proliferation via PI3K/Akt pathway. •Sam68 modulated functional recovery after sciatic nerve crush.« less

Rapamycin attenuates BAFF-extended proliferation and survival via disruption of mTORC1/2 signaling in normal and neoplastic B-lymphoid cells.

PubMed

Zeng, Qingyu; Qin, Shanshan; Zhang, Hai; Liu, Beibei; Qin, Jiamin; Wang, Xiaoxue; Zhang, Ruijie; Liu, Chunxiao; Dong, Xiaoqing; Zhang, Shuangquan; Huang, Shile; Chen, Long

2018-01-01

B cell activating factor from the TNF family (BAFF) stimulates B-cell proliferation and survival, but excessive BAFF promotes the development of aggressive B cells leading to malignant and autoimmune diseases. Recently, we have reported that rapamycin, a macrocyclic lactone, attenuates human soluble BAFF (hsBAFF)-stimulated B-cell proliferation/survival by suppressing mTOR-mediated PP2A-Erk1/2 signaling pathway. Here, we show that the inhibitory effect of rapamycin on hsBAFF-promoted B cell proliferation/survival is also related to blocking hsBAFF-stimulated phosphorylation of Akt, S6K1, and 4E-BP1, as well as expression of survivin in normal and B-lymphoid (Raji and Daudi) cells. It appeared that both mTORC1 and mTORC2 were involved in the inhibitory activity of rapamycin, as silencing raptor or rictor enhanced rapamycin's suppression of hsBAFF-induced survivin expression and proliferation/viability in B cells. Also, PP242, an mTORC1/2 kinase inhibitor, repressed survivin expression, and cell proliferation/viability more potently than rapamycin (mTORC1 inhibitor) in B cells in response to hsBAFF. Of interest, ectopic expression of constitutively active Akt (myr-Akt) or constitutively active S6K1 (S6K1-ca), or downregulation of 4E-BP1 conferred resistance to rapamycin's attenuation of hsBAFF-induced survivin expression and B-cell proliferation/viability, whereas overexpression of dominant negative Akt (dn-Akt) or constitutively hypophosphorylated 4E-BP1 (4EBP1-5A), or downregulation of S6K1, or co-treatment with Akt inhibitor potentiated the inhibitory effects of rapamycin. The findings indicate that rapamycin attenuates excessive hsBAFF-induced cell proliferation/survival via blocking mTORC1/2 signaling in normal and neoplastic B-lymphoid cells. Our data underscore that rapamycin may be a potential agent for preventing excessive BAFF-evoked aggressive B-cell malignancies and autoimmune diseases. © 2017 Wiley Periodicals, Inc.

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

Ramos-Solano, Moisés, E-mail: mrsolano84@gmail.com; Programa de Doctorado en Ciencias Biomédica, Centro Universitario de Ciencias de la Salud; Meza-Canales, Ivan D., E-mail: imezacanales@ice.mpg.de

According to the multifactorial model of cervical cancer (CC) causation, it is now recognized that other modifications, in addition to Human papillomavirus (HPV) infection, are necessary for the development of this neoplasia. Among these, it has been proposed that a dysregulation of the WNT pathway might favor malignant progression of HPV-immortalized keratinocytes. The aim of this study was to identify components of the WNT pathway differentially expressed in CC vs. non-tumorigenic, but immortalized human keratinocytes. Interestingly, WNT7A expression was found strongly downregulated in cell lines and biopsies derived from CC. Restoration of WNT7A in CC-derived cell lines using a lentiviralmore » gene delivery system or after adding a recombinant human protein decreases cell proliferation. Likewise, WNT7A silencing in non-tumorigenic cells markedly accelerates proliferation. Decreased WNT7A expression was due to hypermethylation at particular CpG sites. To our knowledge, this is the first study reporting reduced WNT7A levels in CC-derived cells and that ectopic WNT7A restoration negatively affects cell proliferation and migration. - Highlights: • WNT7A is expressed in normal keratinocytes or cervical cells without lesion. • WNT7A is significantly reduced in cervical cancer-derived cells. • Restoration of WNT7A expression in HeLa decreases proliferation and cell migration. • Silencing of WNT7A in HaCaT induces an increased proliferation and migration rate. • Decreased WNT7A expression in this model is due to hypermethylation.« less

Exogenous FABP4 increases breast cancer cell proliferation and activates the expression of fatty acid transport proteins.

PubMed

Guaita-Esteruelas, Sandra; Bosquet, Alba; Saavedra, Paula; Gumà, Josep; Girona, Josefa; Lam, Eric W-F; Amillano, Kepa; Borràs, Joan; Masana, Lluís

2017-01-01

Adipose tissue plays an important role in tumor progression, because it provides nutrients and adipokines to proliferating cells. Fatty acid binding protein 4 (FABP4) is a key adipokine for fatty acid transport. In metabolic pathologies, plasma levels of FABP4 are increased. However, the role of this circulating protein is unknown. Recent studies have demonstrated that FABP4 might have a role in tumor progression, but the molecular mechanisms involved are still unclear. In this study, we analysed the role of eFABP4 (exogenous FABP4) in breast cancer progression. MCF-7 and MDA-MB-231 breast cancer cells did not express substantial levels of FABP4 protein, but intracellular FABP4 levels increased after eFABP4 incubation. Moreover, eFABP4 enhanced the proliferation of these breast cancer cells but did not have any effect on MCF-7 and MDA-MB-231 cell migration. Additionally, eFABP4 induced the AKT and MAPK signaling cascades in breast cancer cells, and the inhibition of these pathways reduced the eFBAP4-mediated cell proliferation. Interestingly, eFABP4 treatment in MCF-7 cells increased levels of the transcription factor FoxM1 and the fatty acid transport proteins CD36 and FABP5. In summary, we showed that eFABP4 plays a key role in tumor proliferation and activates the expression of fatty acid transport proteins in MCF-7 breast cancer cells. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Inflammation-Induced Cell Proliferation Potentiates DNA Damage-Induced Mutations In Vivo

PubMed Central

Kiraly, Orsolya; Gong, Guanyu; Olipitz, Werner; Muthupalani, Sureshkumar; Engelward, Bevin P.

2015-01-01

Mutations are a critical driver of cancer initiation. While extensive studies have focused on exposure-induced mutations, few studies have explored the importance of tissue physiology as a modulator of mutation susceptibility in vivo. Of particular interest is inflammation, a known cancer risk factor relevant to chronic inflammatory diseases and pathogen-induced inflammation. Here, we used the fluorescent yellow direct repeat (FYDR) mice that harbor a reporter to detect misalignments during homologous recombination (HR), an important class of mutations. FYDR mice were exposed to cerulein, a potent inducer of pancreatic inflammation. We show that inflammation induces DSBs (γH2AX foci) and that several days later there is an increase in cell proliferation. While isolated bouts of inflammation did not induce HR, overlap between inflammation-induced DNA damage and inflammation-induced cell proliferation induced HR significantly. To study exogenously-induced DNA damage, animals were exposed to methylnitrosourea, a model alkylating agent that creates DNA lesions relevant to both environmental exposures and cancer chemotherapy. We found that exposure to alkylation damage induces HR, and importantly, that inflammation-induced cell proliferation and alkylation induce HR in a synergistic fashion. Taken together, these results show that, during an acute bout of inflammation, there is a kinetic barrier separating DNA damage from cell proliferation that protects against mutations, and that inflammation-induced cell proliferation greatly potentiates exposure-induced mutations. These studies demonstrate a fundamental mechanism by which inflammation can act synergistically with DNA damage to induce mutations that drive cancer and cancer recurrence. PMID:25647331

Myeloid leukemia factor-1 is a novel modulator of neonatal rat cardiomyocyte proliferation.

PubMed

Rangrez, Ashraf Yusuf; Pott, Jost; Kluge, Annika; Frauen, Robert; Stiebeling, Katharina; Hoppe, Phillip; Sossalla, Samuel; Frey, Norbert; Frank, Derk

2017-04-01

The present study focuses on the identification of the gene expression profile of neonatal rat cardiomyocytes (NRVCMs) after dynamic mechanical stretch through microarrays of RNA isolated from cells stretched for 2, 6 or 24h. In this analysis, myeloid leukemia factor-1 (MLF1) was found to be significantly downregulated during the course of stretch. We found that MLF1 is highly expressed in the heart, however, its cardiac function is unknown yet. In line with microarray data, MLF1 was profoundly downregulated in in vivo mouse models of cardiomyopathy, and also significantly reduced in the hearts of human patients with dilated cardiomyopathy. Our data indicates that the overexpression of MLF1 in NRVCMs inhibited cell proliferation while augmenting apoptosis. Conversely, knockdown of MLF1 protected NRVCMs from apoptosis and promoted cell proliferation. Moreover, we found that knockdown of MLF1 protected NRVCMs from hypoxia-induced cell death. The observed accelerated apoptosis is attributed to the activation of caspase-3/-7/PARP-dependent apoptotic signaling and upregulation of p53. Most interestingly, MLF1 knockdown significantly upregulated the expression of D cyclins suggesting its possible role in cyclin-dependent cell proliferation. Taken together, we, for the first time, identified an important role for MLF1 in NRVCM proliferation. Copyright © 2017 Elsevier B.V. All rights reserved.

Voltage-Gated Ion Channels in Cancer Cell Proliferation

PubMed Central

Rao, Vidhya R.; Perez-Neut, Mathew; Kaja, Simon; Gentile, Saverio

2015-01-01

Changes of the electrical charges across the surface cell membrane are absolutely necessary to maintain cellular homeostasis in physiological as well as in pathological conditions. The opening of ion channels alter the charge distribution across the surface membrane as they allow the diffusion of ions such as K+, Ca++, Cl−, Na+. Traditionally, voltage-gated ion channels (VGIC) are known to play fundamental roles in controlling rapid bioelectrical signaling including action potential and/or contraction. However, several investigations have revealed that these classes of proteins can also contribute significantly to cell mitotic biochemical signaling, cell cycle progression, as well as cell volume regulation. All these functions are critically important for cancer cell proliferation. Interestingly, a variety of distinct VGICs are expressed in different cancer cell types, including metastasis but not in the tissues from which these tumors were generated. Given the increasing evidence suggesting that VGIC play a major role in cancer cell biology, in this review we discuss the role of distinct VGIC in cancer cell proliferation and possible therapeutic potential of VIGC pharmacological manipulation. PMID:26010603

A novel PKC-ι inhibitor abrogates cell proliferation and induces apoptosis in neuroblastoma.

PubMed

Pillai, Prajit; Desai, Shraddha; Patel, Rekha; Sajan, Mini; Farese, Robert; Ostrov, David; Acevedo-Duncan, Mildred

2011-05-01

Protein Kinase C-iota (PKC-ι), an atypical protein kinase C isoform manifests its potential as an oncogene by targeting various aspects of cancer cells such as growth, invasion and survival. PKC-ι confers resistance to drug-induced apoptosis in cancer cells. The acquisition of drug resistance is a major obstacle to good prognosis in neuroblastoma. The focus of this research was to identify the efficacy of [4-(5-amino-4-carbamoylimidazol-1-yl)-2,3-dihydroxycyclopentyl] methyl dihydrogen phosphate (ICA-1) as a novel PKC-ι inhibitor in neuroblastoma cell proliferation and apoptosis. ICA-1 specifically inhibits the activity of PKC-ι but not that of PKC-zeta (PKC-ζ), the closely related atypical PKC family member. The IC(50) for the kinase activity assay was approximately 0.1μM which is 1000 times less than that of aurothiomalate, a known PKC-ι inhibitor. Cyclin dependent kinase 7 (Cdk7) phosphorylates cyclin dependent kinases (cdks) and promotes cell proliferation. Our data shows that PKC-ι is an in vitro Cdk7 kinase and the phosphorylation of Cdk7 by PKC-ι was potently inhibited by ICA-1. Furthermore, our data shows that neuroblastoma cells proliferate via a PKC-ι/Cdk7/cdk2 cell signaling pathway and ICA-1 mediates its antiproliferative effects by inhibiting this pathway. ICA-1 (0.1μM) inhibited the in vitro proliferation of BE(2)-C neuroblastoma cells by 58% (P=0.01). Additionally, ICA-1 also induced apoptosis in neuroblastoma cells. Interestingly, ICA-1 did not affect the proliferation of normal neuronal cells suggesting its potential as chemotherapeutic with low toxicity. Hence, our results emphasize the potential of ICA-1 as a novel PKC-ι inhibitor and chemotherapeutic agent for neuroblastoma. Published by Elsevier Ltd.

Anti-proliferative therapy for HIV cure: a compound interest approach.

PubMed

Reeves, Daniel B; Duke, Elizabeth R; Hughes, Sean M; Prlic, Martin; Hladik, Florian; Schiffer, Joshua T

2017-06-21

In the era of antiretroviral therapy (ART), HIV-1 infection is no longer tantamount to early death. Yet the benefits of treatment are available only to those who can access, afford, and tolerate taking daily pills. True cure is challenged by HIV latency, the ability of chromosomally integrated virus to persist within memory CD4 + T cells in a non-replicative state and activate when ART is discontinued. Using a mathematical model of HIV dynamics, we demonstrate that treatment strategies offering modest but continual enhancement of reservoir clearance rates result in faster cure than abrupt, one-time reductions in reservoir size. We frame this concept in terms of compounding interest: small changes in interest rate drastically improve returns over time. On ART, latent cell proliferation rates are orders of magnitude larger than activation and new infection rates. Contingent on subtypes of cells that may make up the reservoir and their respective proliferation rates, our model predicts that coupling clinically available, anti-proliferative therapies with ART could result in functional cure within 2-10 years rather than several decades on ART alone.

Hepatocyte-specific deletion of hepatocyte nuclear factor-4α in adult mice results in increased hepatocyte proliferation.

PubMed

Walesky, Chad; Gunewardena, Sumedha; Terwilliger, Ernest F; Edwards, Genea; Borude, Prachi; Apte, Udayan

2013-01-01

Hepatocyte nuclear factor-4α (HNF4α) is known as the master regulator of hepatocyte differentiation. Recent studies indicate that HNF4α may inhibit hepatocyte proliferation via mechanisms that have yet to be identified. Using a HNF4α knockdown mouse model based on delivery of inducible Cre recombinase via an adeno-associated virus 8 viral vector, we investigated the role of HNF4α in the regulation of hepatocyte proliferation. Hepatocyte-specific deletion of HNF4α resulted in increased hepatocyte proliferation. Global gene expression analysis showed that a majority of the downregulated genes were previously known HNF4α target genes involved in hepatic differentiation. Interestingly, ≥500 upregulated genes were associated with cell proliferation and cancer. Furthermore, we identified potential negative target genes of HNF4α, many of which are involved in the stimulation of proliferation. Using chromatin immunoprecipitation analysis, we confirmed binding of HNF4α at three of these genes. Furthermore, overexpression of HNF4α in mouse hepatocellular carcinoma cells resulted in a decrease in promitogenic gene expression and cell cycle arrest. Taken together, these data indicate that, apart from its role in hepatocyte differentiation, HNF4α actively inhibits hepatocyte proliferation by repression of specific promitogenic genes.

miR-30a can inhibit DNA replication by targeting RPA1 thus slowing cancer cell proliferation.

PubMed

Zou, Zhenyou; Ni, Mengjie; Zhang, Jing; Chen, Yongfeng; Ma, Hongyu; Qian, Shihan; Tang, Longhua; Tang, Jiamei; Yao, Hailun; Zhao, Chengbin; Lu, Xiongwen; Sun, Hongyang; Qian, Jue; Mao, Xiaoting; Lu, Xulin; Liu, Qun; Zen, Juping; Wu, Hanbing; Bao, Zhaosheng; Lin, Shudan; Sheng, Hongyu; Li, Yunlong; Liang, Yong; Chen, Zhiqiang; Zong, Dan

2016-07-15

Cell proliferation was inhibited following forced over-expression of miR-30a in the ovary cancer cell line A2780DX5 and the gastric cancer cell line SGC7901R. Interestingly, miR-30a targets the DNA replication protein RPA1, hinders the replication of DNA and induces DNA fragmentation. Furthermore, ataxia telangiectasia mutated (ATM) and checkpoint kinase 2 (CHK2) were phosphorylated after DNA damage, which induced p53 expression, thus triggering the S-phase checkpoint, arresting cell cycle progression and ultimately initiating cancer cell apoptosis. Therefore, forced miR-30a over-expression in cancer cells can be a potential way to inhibit tumour development. © 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

Hypoxia-inducible factor-1α promotes cell survival during ammonia stress response in ovarian cancer stem-like cells

PubMed Central

Kitajima, Shojiro; Lee, Kian Leong; Hikasa, Hiroki; Sun, Wendi; Huang, Ruby Yun-Ju; Yang, Henry; Matsunaga, Shinji; Yamaguchi, Takehiro; Araki, Marito; Kato, Hiroyuki

2017-01-01

Ammonia is a toxic by-product of metabolism that causes cellular stresses. Although a number of proteins are involved in adaptive stress response, specific factors that counteract ammonia-induced cellular stress and regulate cell metabolism to survive against its toxicity have yet to be identified. We demonstrated that the hypoxia-inducible factor-1α (HIF-1α) is stabilized and activated by ammonia stress. HIF-1α activated by ammonium chloride compromises ammonia-induced apoptosis. Furthermore, we identified glutamine synthetase (GS) as a key driver of cancer cell proliferation under ammonia stress and glutamine-dependent metabolism in ovarian cancer stem-like cells expressing CD90. Interestingly, activated HIF-1α counteracts glutamine synthetase function in glutamine metabolism by facilitating glycolysis and elevating glucose dependency. Our studies reveal the hitherto unknown functions of HIF-1α in a biphasic ammonia stress management in the cancer stem-like cells where GS facilitates cell proliferation and HIF-1α contributes to the metabolic remodeling in energy fuel usage resulting in attenuated proliferation but conversely promoting cell survival. PMID:29383096

Metabolic reprogramming: a hallmark of viral oncogenesis.

PubMed

Lévy, P; Bartosch, B

2016-08-11

More than 1 in 10 cases of cancer in the world are due to chronic viral infections. Viruses induce oncogenesis by targeting the same pathways known to be responsible for neoplasia in tumor cells, such as control of cell cycle progression, cell migration, proliferation and evasion from cell death and the host's immune defense. In addition, metabolic reprogramming has been identified over a century ago as a requirement for growth of transformed cells. Renewed interest in this topic has emerged recently with the discovery that basically all metabolic changes in tumor cells are finely orchestrated by oncogenes and tumor suppressors. Indeed, cancer cells activate biosynthetic pathways in order to provide them with sufficient levels of energy and building blocks to proliferate. Interestingly, viruses introduce into their host cells similar metabolic adaptations, and importantly, it seems that they depend on these changes for their persistence and amplification. The central carbon metabolism, for example, is not only frequently altered in tumor cells but also modulated by human papillomavirus, hepatitis B and C viruses, Epstein-Barr virus and Kaposi's Sarcoma-associated virus. Moreover, adenoviruses (Ad) and human cytomegalovirus, which are not directly oncogenic but present oncomodulatory properties, also divert cellular metabolism in a tumor cell-like mnner. Thus, metabolic reprogramming appears to be a hallmark of viral infection and provides an interesting therapeutic target, in particular, for oncogenic viruses. Therapeutic targeting of metabolic pathways may not only allow to eliminate or control the viral infection but also to prevent virus-induced carcinogenesis.

N-acetyl-L-cysteine increases MnSOD activity and enhances the recruitment of quiescent human fibroblasts to the proliferation cycle during wound healing.

PubMed

Mao, Gaowei; Goswami, Monali; Kalen, Amanda L; Goswami, Prabhat C; Sarsour, Ehab H

2016-01-01

The rebuilding of the connective tissue during wound healing requires the recruitment of fibroblasts to the wound area as well as reentry of quiescent fibroblasts to the proliferative cycle. Whether this process can be modulated by a small molecular weight thiol antioxidant N-acetyl-L-cysteine (NAC) was tested in normal human skin fibroblasts (NHFs) using a uni-directional wound healing assay. NAC treated cells demonstrated a decreased migration rate but increased number of proliferating cells recruited into the wound area post wounding. Fifteen day quiescent control and NAC treated NHFs were re-plated at a lower density and cell numbers counted at different days post-plating. Interestingly, NAC treated cells exhibited increased cellular proliferation indicated by both decreased cell population doubling time and increased S phase cells. NAC treated cells demonstrated decreased steady state levels of reactive oxygen species as well as increased protein and activity levels of manganese superoxide dismutase (MnSOD). NAC treatment failed to induce proliferation in quiescent cells lacking MnSOD expression. These results demonstrate that NAC enhanced the recruitment of quiescent NHFs into proliferation cycle during wound healing. Our results also suggest that the wound healing properties of NAC might be due to its ability to induce and enhance MnSOD expression and activity. Altogether, these findings suggest NAC might be potentially developed as a dietary intervention to improve tissue injury in animals and humans.

NFκB-mediated cyclin D1 expression by microRNA-21 influences renal cancer cell proliferation.

PubMed

Bera, Amit; Ghosh-Choudhury, Nandini; Dey, Nirmalya; Das, Falguni; Kasinath, Balakuntalam S; Abboud, Hanna E; Choudhury, Goutam Ghosh

2013-12-01

MicroRNAs regulate post-transcriptomic landscape in many tumors including renal cell carcinoma. We have recently shown significantly increased expression of miR-21 in renal tumors and that this miRNA contributes to the proliferation of renal cancer cells in culture. However, the mechanism by which miR-21 regulates renal cancer cell proliferation is poorly understood. Addiction to constitutive NFκB activity is hallmark of many cancers including renal cancer. Using miR-21 Sponge in renal cancer cells to block endogenous function of miR-21, we show inhibition of phosphorylation of p65 subunit of NFκB, IKKβ and IκB, which results in attenuation of NFκB transcriptional activity. Subtle reduction in the tumor suppressor PTEN has been linked to various malignancies. We showed previously that miR-21 targeted PTEN in renal cancer cells. Inhibition of PTEN by siRNAs restored miR-21 Sponge-induced suppression of phosphorylation of p65, IKKβ, IκB and NFκB transcriptional activity along with reversal of miR-21 Sponge-reduced phosphorylation of Akt. Expression of constitutively active Akt protected against miR-21 Sponge- and PTEN-mediated decrease in p65/IKKβ/IκB phosphorylation and NFκB transcriptional activity. Furthermore, IKKβ and p65 were required for miR-21-induced renal cancer cell proliferation. Interestingly, miR-21 controlled the expression of cyclin D1 through NFκB-dependent transcription. Finally, we demonstrate that miR-21-regulated renal cancer cell proliferation is mediated by cyclin D1 and CDK4. Together, our results establish a molecular order of a phosphatase-kinase couple involving PTEN/Akt/IKKβ and NFκB-dependent cyclin D1 expression for renal carcinoma cell proliferation by increased miR-21 levels. © 2013.

NFκB-mediated cyclin D1 expression by microRNA-21 influences renal cancer cell proliferation

PubMed Central

Bera, Amit; Ghosh-Choudhury, Nandini; Dey, Nirmalya; Das, Falguni; Kasinath, Balakuntalam S.; Abboud, Hanna E.; Choudhury, Goutam Ghosh

2013-01-01

MicroRNAs regulate post-transcriptomic landscape in many tumors including renal cell carcinoma. We have recently shown significantly increased expression of miR-21 in renal tumors and that this miRNA contributes to the proliferation of renal cancer cells in culture. However, the mechanism by which miR-21 regulates renal cancer cells proliferation is poorly understood. Addiction to constitutive NFκB activity is hallmark of many cancers including renal cancer. Using miR-21 Sponge in renal cancer cells to block endogenous function of miR-21, we show inhibition of phosphorylation of p65 subunit of NFκB, IKKβ and IκB, which results in attenuation of NFκB transcriptional activity. Subtle reduction in the tumor suppressor PTEN has been linked to various malignancies. We showed previously that miR-21 targeted PTEN in renal cancer cells. Inhibition of PTEN by siRNAs restored miR-21 Sponge-induced suppression of phosphorylation of p65, IKKβ, IκB and NFκB transcriptional activity along with reversal of miR-21 Sponge-reduced phosphorylation of Akt. Expression of constitutively active Akt protected against miR-21 Sponge- and PTEN-mediated decrease in p65/IKKβ/IκB phosphorylation and NFκB transcriptional activity. Furthermore, IKKβ and p65 were required for miR-21-induced renal cancer cell proliferation. Interestingly, miR-21 controlled the expression of cyclin D1 through NFκB-dependent transcription. Finally, we demonstrate that miR-21-regulated renal cancer cell proliferation is mediated by cyclin D1 and CDK4. Together, our results establish a molecular order of a phosphatase-kinase couple involving PTEN/Akt/IKKβ and NFκB-dependent cyclin D1 expression for renal carcinoma cell proliferation by increased miR-21 levels. PMID:23981302

BMP signaling balances proliferation and differentiation of muscle satellite cell descendants

PubMed Central

2011-01-01

Background The capacity of muscle to grow or to regenerate after damage is provided by adult stem cells, so called satellite cells, which are located under the basement lamina of each myofiber. Upon activation satellite cells enter the cell cycle, proliferate and differentiate into myoblasts, which fuse to injured myofibers or form new fibers. These processes are tightly controlled by many growth factors. Results Here we investigate the role of bone morphogenetic proteins (BMPs) during satellite cell differentiation. Unlike the myogenic C2C12 cell line, primary satellite cells do not differentiate into osteoblasts upon BMP signaling. Instead BMP signaling inhibits myogenic differentiation of primary satellite cells ex vivo. In contrast, inhibition of BMP signaling results in cell cycle exit, followed by enhanced myoblast differentiation and myotube formation. Using an in vivo trauma model we demonstrate that satellite cells respond to BMP signals during the regeneration process. Interestingly, we found the BMP inhibitor Chordin upregulated in primary satellite cell cultures and in regenerating muscles. In both systems Chordin expression follows that of Myogenin, a marker for cells committed to differentiation. Conclusion Our data indicate that BMP signaling plays a critical role in balancing proliferation and differentiation of activated satellite cells and their descendants. Initially, BMP signals maintain satellite cells descendants in a proliferating state thereby expanding cell numbers. After cells are committed to differentiate they upregulate the expression of the BMP inhibitor Chordin thereby supporting terminal differentiation and myotube formation in a negative feedback mechanism. PMID:21645366

A Phenotypic Cell-Binding Screen Identifies a Novel Compound Targeting Triple-Negative Breast Cancer.

PubMed

Chen, Luxi; Long, Chao; Youn, Jonghae; Lee, Jiyong

2018-06-11

We describe a "phenotypic cell-binding screen" by which therapeutic candidate targeting cancer cells of a particular phenotype can be isolated without knowledge of drug targets. Chemical library beads are incubated with cancer cells of the phenotype of interest in the presence of cancer cells lacking the phenotype of interest, and then the beads bound to only cancer cells of the phenotype of interest are selected as hits. We have applied this screening strategy in discovering a novel compound (LC129-8) targeting triple-negative breast cancer (TNBC). LC129-8 displayed highly specific binding to TNBC in cancer cell lines and patient-derived tumor tissues. LC129-8 exerted anti-TNBC activity by inducing apoptosis, inhibiting proliferation, reversing epithelial-mesenchymal transition, downregulating cancer stem cell activity and blocking in vivo tumor growth.

Military Vision Research Program. Addendum

DTIC Science & Technology

2011-08-01

keratitis, ocular cicatricial pemphigoid and dry eye syndromes. In some diseases, overproduction of mucin owing to excessive goblet cell proliferation and...cell density and mucin secretion has been observed in dry eye patients and inflammation can lead to goblet cell apoptosis; 2. A reduced goblet cell...of goblet cell mucin secretion in severe dry eye patients.3 It was therefore of interest to investigate the role of goblet cells in regulating

A new extract of the plant calendula officinalis produces a dual in vitro effect: cytotoxic anti-tumor activity and lymphocyte activation

PubMed Central

Jiménez-Medina, Eva; Garcia-Lora, Angel; Paco, Laura; Algarra, Ignacio; Collado, Antonia; Garrido, Federico

2006-01-01

Background Phytopharmacological studies of different Calendula extracts have shown anti-inflamatory, anti-viral and anti-genotoxic properties of therapeutic interest. In this study, we evaluated the in vitro cytotoxic anti-tumor and immunomodulatory activities and in vivo anti-tumor effect of Laser Activated Calendula Extract (LACE), a novel extract of the plant Calendula Officinalis (Asteraceae). Methods An aqueous extract of Calendula Officinalis was obtained by a novel extraction method in order to measure its anti-tumor and immunomodulatory activities in vitro. Tumor cell lines derived from leukemias, melanomas, fibrosarcomas and cancers of breast, prostate, cervix, lung, pancreas and colorectal were used and tumor cell proliferation in vitro was measured by BrdU incorporation and viable cell count. Effect of LACE on human peripheral blood lymphocyte (PBL) proliferation in vitro was also analyzed. Studies of cell cycle and apoptosis were performed in LACE-treated cells. In vivo anti-tumor activity was evaluated in nude mice bearing subcutaneously human Ando-2 melanoma cells. Results The LACE extract showed a potent in vitro inhibition of tumor cell proliferation when tested on a wide variety of human and murine tumor cell lines. The inhibition ranged from 70 to 100%. Mechanisms of inhibition were identified as cell cycle arrest in G0/G1 phase and Caspase-3-induced apoptosis. Interestingly, the same extract showed an opposite effect when tested on PBLs and NKL cell line, in which in vitro induction of proliferation and activation of these cells was observed. The intraperitoneal injection or oral administration of LACE extract in nude mice inhibits in vivo tumor growth of Ando-2 melanoma cells and prolongs the survival day of the mice. Conclusion These results indicate that LACE aqueous extract has two complementary activities in vitro with potential anti-tumor therapeutic effect: cytotoxic tumor cell activity and lymphocyte activation. The LACE extract presented in vivo anti-tumoral activity in nude mice against tumor growth of Ando-2 melanoma cells. PMID:16677386

Differential effects of a complex organochlorine mixture on the proliferation of breast cancer cell lines

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

Aube, Michel, E-mail: 4aubem@videotron.ca; Larochelle, Christian, E-mail: christian.larochelle@inspq.qc.ca; Ayotte, Pierre, E-mail: pierre.ayotte@inspq.qc.ca

2011-04-15

Organochlorine compounds (OCs) are a group of persistent chemicals that accumulate in fatty tissues with age. Although OCs has been tested individually for their capacity to induce breast cancer cell proliferation, few studies examined the effect of complex mixtures that comprise compounds frequently detected in the serum of women. We constituted such an OC mixture containing 15 different components in environmentally relevant proportions and assessed its proliferative effects in four breast cancer cell lines (MCF-7, T47D, CAMA-1, MDAMB231) and in non-cancerous CV-1 cells. We also determined the capacity of the mixture to modulate cell cycle stage of breast cancer cellsmore » and to induce estrogenic and antiandrogenic effects using gene reporter assays. We observed that low concentrations of the mixture (100x10{sup 3} and 50x10{sup 3} dilutions) stimulated the proliferation of MCF-7 cells while higher concentrations (10x10{sup 3} and 5x10{sup 3} dilutions) had the opposite effect. In contrast, the mixture inhibited the proliferation of non-hormone-dependent cell lines. The mixture significantly increased the number of MCF-7 cells entering the S phase, an effect that was blocked by the antiestrogen ICI 182,780. Low concentrations of the mixture also caused an increase in CAMA-1 cell proliferation but only in the presence estradiol and dihydrotestosterone (p<0.05 at the 50x10{sup 3} dilution). DDT analogs and polychlorinated biphenyls all had the capacity to stimulate the proliferation of CAMA-1 cells in the presence of sex steroids. Reporter gene assays further revealed that the mixture and several of its constituents (DDT analogs, aldrin, dieldrin, {beta}-hexachlorocyclohexane, toxaphene) induced estrogenic effects, whereas the mixture and several components (DDT analogs, aldrin, dieldrin and PCBs) inhibited the androgen signaling pathway. Our results indicate that the complex OC mixture increases the proliferation of MCF-7 cells due to its estrogenic potential. The proliferative effect of the mixture on CAMA-1 cells in the presence of sex steroids appears mostly due to the antiandrogenic properties of p,p'-DDE, a major constituent of the mixture. Other mixtures of contaminants that include emerging compounds of interest such as brominated flame retardants and perfluoroalkyl compounds should be tested for their capacity to induce breast cancer cell proliferation. - Research highlights: {yields} We studied effects of a complex organochlorine mixture on breast cancer cell growth. {yields} Weak xenoestrogens in the mixture stimulated the proliferation of MCF-7 cells. {yields} Antiandrogens increased the proliferation CAMA-1 cells grown with sex steroids. {yields} High concentrations of the mixture decreased the proliferation of all cell lines.« less

Melanoma exosomes deliver a complex biological payload that upregulates PTPN11 to suppress T lymphocyte function

PubMed Central

Wu, Yueting; Deng, Wentao; McGinley, Emily Chambers; Klinke, David J.

2017-01-01

Summary As exosomes are emerging as a new mode of intercellular communication, we hypothesized that the payload contained within exosomes is shaped by somatic evolution. To test this, we assayed the impact on primary CD8+ T cell function, a key mechanism for anti-tumor immunity, of exosomes derived from three melanoma-related cell lines. While morphologically similar, exosomes from each cell line were functionally different, as B16F0 exosomes dose-dependently suppressed T cell proliferation. In contrast, Cloudman S91 exosomes promoted T cell proliferation and Melan-A exosomes had a negligible effect on primary CD8+ T cells. Mechanistically, transcript profiling suggested that exosomal mRNA is enriched for full-length mRNAs that target immune-related pathways. Interestingly, B16F0 exosomes were unique in that they contained both protein and mRNA for Ptpn11, which inhibited T cell proliferation. Collectively, the results suggest that upregulation of PTPN11 by B16F0 exosomes to tumor infiltrating lymphocytes would bypass the extracellular control of the immune checkpoints. PMID:27930879

A simple non-perturbing cell migration assay insensitive to proliferation effects.

PubMed

Glenn, Honor L; Messner, Jacob; Meldrum, Deirdre R

2016-08-18

Migration is a fundamental cellular behavior that plays an indispensable role in development and homeostasis, but can also contribute to pathology such as cancer metastasis. Due to its relevance to many aspects of human health, the ability to accurately measure cell migration is of broad interest, and numerous approaches have been developed. One of the most commonly employed approaches, because of its simplicity and throughput, is the exclusion zone assay in which cells are allowed to migrate into an initially cell-free region. A major drawback of this assay is that it relies on simply counting cells in the exclusion zone and therefore cannot distinguish the effects of proliferation from migration. We report here a simple modification to the exclusion zone migration assay that exclusively measures cell migration and is not affected by proliferation. This approach makes use of a lineage-tracing vital stain that is retained through cell generations and effectively reads out migration relative to the original, parental cell population. This modification is simple, robust, non-perturbing, and inexpensive. We validate the method in a panel of cell lines under conditions that inhibit or promote migration and demonstrate its use in normal and cancer cell lines as well as primary cells.

Neural and oligodendrocyte progenitor cells: transferrin effects on cell proliferation

PubMed Central

Silvestroff, Lucas; Franco, Paula Gabriela; Pasquini, Juana María

2013-01-01

NSC (neural stem cells)/NPC (neural progenitor cells) are multipotent and self-renew throughout adulthood in the SVZ (subventricular zone) of the mammalian CNS (central nervous system). These cells are considered interesting targets for CNS neurodegenerative disorder cell therapies, and understanding their behaviour in vitro is crucial if they are to be cultured prior to transplantation. We cultured the SVZ tissue belonging to newborn rats under the form of NS (neurospheres) to evaluate the effects of Tf (transferrin) on cell proliferation. The NS were heterogeneous in terms of the NSC/NPC markers GFAP (glial fibrillary acidic protein), Nestin and Sox2 and the OL (oligodendrocyte) progenitor markers NG2 (nerve/glia antigen 2) and PDGFRα (platelet-derived growth factor receptor α). The results of this study indicate that aTf (apoTransferrin) is able to increase cell proliferation of SVZ-derived cells in vitro, and that these effects were mediated at least in part by the TfRc1 (Tf receptor 1). Since OPCs (oligodendrocyte progenitor cells) represent a significant proportion of the proliferating cells in the SVZ-derived primary cultures, we used the immature OL cell line N20.1 to show that Tf was able to augment the proliferation rate of OPC, either by adding aTf to the culture medium or by overexpressing rat Tf in situ. The culture medium supplemented with ferric iron, together with aTf, increased the DNA content, while ferrous iron did not. The present work provides data that could have a potential application in human cell replacement therapies for neurodegenerative disease and/or CNS injury that require the use of in vitro amplified NPCs. PMID:23368675

Acrylamide affects proliferation and differentiation of the neural progenitor cell line C17.2 and the neuroblastoma cell line SH-SY5Y.

PubMed

Attoff, K; Kertika, D; Lundqvist, J; Oredsson, S; Forsby, A

2016-09-01

Acrylamide is a well-known neurotoxic compound and people get exposed to the compound by food consumption and environmental pollutants. Since acrylamide crosses the placenta barrier, the fetus is also being exposed resulting in a risk for developmental neurotoxicity. In this study, the neural progenitor cell line C17.2 and the neuroblastoma cell line SH-SY5Y were used to study proliferation and differentiation as alerting indicators for developmental neurotoxicity. For both cell lines, acrylamide reduced the number of viable cells by reducing proliferation and inducing cell death in undifferentiated cells. Acrylamide concentrations starting at 10fM attenuated the differentiation process in SH-SY5Y cells by sustaining cell proliferation and neurite outgrowth was reduced at concentrations from 10pM. Acrylamide significantly reduced the number of neurons starting at 1μM and altered the ratio between the different phenotypes in differentiating C17.2 cell cultures. Ten micromolar of acrylamide also reduced the expression of the neuronal and astrocyte biomarkers. Although the neurotoxic concentrations in the femtomolar range seem to be specific for the SH-SY5Y cell line, the fact that micromolar concentrations of acrylamide seem to attenuate the differentiation process in both cell lines raises the interest to further investigations on the possible developmental neurotoxicity of acrylamide. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

PKI-587 and sorafenib alone and in combination on inhibition of liver cancer stem cell proliferation

PubMed Central

Gedaly, Roberto; Galuppo, Roberto; Musgrave, Yolanda; Angulo, Paul; Hundley, Jonathan; Shah, Malay; Daily, Michael F.; Chen, Changguo; Cohen, Donald A.; Spear, Brett T.; Evers, B. Mark

2015-01-01

Background Deregulated Ras/Raf/mitogen-activated protein kinase and PI3 K/AKT/mTOR signaling pathways are significant in hepatocellular carcinoma proliferation (HCC). In this study we evaluated differences in the antiproliferative effect of dual PI3 K/Akt/mTOR and Ras/Raf/mitogen-activated protein kinase inhibition of non liver cancer stem cell lines (PLC and HuH7) and liver cancer stem cell (LCSC) lines (CD133, CD44, CD24, and aldehyde dehydrogenase 1-positive cells). Materials and methods Flow cytometry was performed on the resulting tumors to identify the LCSC markers CD133, CD44, CD24, and aldehyde dehydrogenase 1. Methylthiazol tetrazolium assay was used to assess cellular proliferation. Finally, a Western blot assay was used to evaluate for inhibition of specific enzymes in these two signaling pathways. Results Using flow cytometry, we found that LCSC contain 64.4% CD133 + cells, 83.2% CD44 + cells, and 96.4% CD24 + cells. PKI-587 and sorafenib caused inhibiton of LCSC and HCC cell proliferation. PLC cells were more sensitive to PKI-587 than LCSC or Huh7 (P < 0.001). Interestingly, HuH7 cells were more sensitive to sorafenib than LCSC or PLC cells. Additionally, combination therapy with PKI-587 and sorafenib caused significantly more inhibition than monotherapy in HuH7, PLC, and LCSC. Using the methylthiazol tetrazolium assay, we found that the LCSC proliferation was inhibited with sorafenib monotherapy 39% at 5 μM (P < 0.001; n = 12) and 67% by PKI-587 at 0.1 μM (P = 0.002, n = 12) compared with control. The combination of PKI-587 and sorafenib, however, synergistically inhibited LCSC proliferation by 86% (P = 0.002; n = 12). Conclusions LCSC (CD133+, CD44+, CD24+) were able to develop very aggressive tumors with low cell concentrations at 4 to 6 wk. Cells CD133+, CD44+, CD24+ demonstrated at least moderate resistance to therapy in vitro. The combination of PKI-587 and sorafenib was better than either drug alone at inhibiting of LCSC and on HCC cell proliferation. PMID:23769634

PKI-587 and sorafenib alone and in combination on inhibition of liver cancer stem cell proliferation.

PubMed

Gedaly, Roberto; Galuppo, Roberto; Musgrave, Yolanda; Angulo, Paul; Hundley, Jonathan; Shah, Malay; Daily, Michael F; Chen, Changguo; Cohen, Donald A; Spear, Brett T; Evers, B Mark

2013-11-01

Deregulated Ras/Raf/mitogen-activated protein kinase and PI3 K/AKT/mTOR signaling pathways are significant in hepatocellular carcinoma proliferation (HCC). In this study we evaluated differences in the antiproliferative effect of dual PI3 K/Akt/mTOR and Ras/Raf/mitogen-activated protein kinase inhibition of non liver cancer stem cell lines (PLC and HuH7) and liver cancer stem cell (LCSC) lines (CD133, CD44, CD24, and aldehyde dehydrogenase 1-positive cells). Flow cytometry was performed on the resulting tumors to identify the LCSC markers CD133, CD44, CD24, and aldehyde dehydrogenase 1. Methylthiazol tetrazolium assay was used to assess cellular proliferation. Finally, a Western blot assay was used to evaluate for inhibition of specific enzymes in these two signaling pathways. Using flow cytometry, we found that LCSC contain 64.4% CD133 + cells, 83.2% CD44 + cells, and 96.4% CD24 + cells. PKI-587 and sorafenib caused inhibiton of LCSC and HCC cell proliferation. PLC cells were more sensitive to PKI-587 than LCSC or Huh7 (P < 0.001). Interestingly, HuH7 cells were more sensitive to sorafenib than LCSC or PLC cells. Additionally, combination therapy with PKI-587 and sorafenib caused significantly more inhibition than monotherapy in HuH7, PLC, and LCSC. Using the methylthiazol tetrazolium assay, we found that the LCSC proliferation was inhibited with sorafenib monotherapy 39% at 5 μM (P < 0.001; n = 12) and 67% by PKI-587 at 0.1 μM (P = 0.002, n = 12) compared with control. The combination of PKI-587 and sorafenib, however, synergistically inhibited LCSC proliferation by 86% (P = 0.002; n = 12). LCSC (CD133+, CD44+, CD24+) were able to develop very aggressive tumors with low cell concentrations at 4 to 6 wk. Cells CD133+, CD44+, CD24+, which demonstrated at least moderate resistance to therapy in vitro. The combination of PKI-587 and sorafenib was better than either drug alone at inhibiting of LCSC and on HCC cell proliferation. Copyright © 2013 Elsevier Inc. All rights reserved.

Proliferation Rates of Bovine Primary Muscle Cells Relate to Liveweight and Carcase Weight in Cattle

PubMed Central

Coles, Chantal A.; Wadeson, Jenny; Leyton, Carolina P.; Siddell, Jason P.; Greenwood, Paul L.; White, Jason D.; McDonagh, Matthew B.

2015-01-01

Muscling in cattle is largely influenced by genetic background, ultimately affecting beef yield and is of major interest to the beef industry. This investigation aimed to determine whether primary skeletal muscle cells isolated from different breeds of cattle with a varying genetic potential for muscling differ in their myogenic proliferative capacity. Primary skeletal muscle cells were isolated and cultured from the Longissimus muscle (LM) of 6 month old Angus, Hereford and Wagyu X Angus cattle. Cells were assessed for rate of proliferation and gene expression of PAX7, MYOD, MYF5, and MYOG. Proliferation rates were found to differ between breeds of cattle whereby myoblasts from Angus cattle were found to proliferate at a greater rate than those of Hereford and Wagyu X Angus during early stages of growth (5–20 hours in culture) in vitro (P < 0.05). The proliferation rates of myoblasts during early stages of culture in vitro were also found to be positively related to the liveweight and carcase weight of cattle (P < 0.05). Gene expression of MYF5 was also found to be significantly down-regulated in WagyuX compared with Angus cattle (P < 0.05). These findings suggest that early events during myogenesis are important for determining liveweight and caracase weights in cattle. PMID:25875203

Expression of Slug in S100β-protein-positive cells of postnatal developing rat anterior pituitary gland.

PubMed

Horiguchi, Kotaro; Fujiwara, Ken; Tsukada, Takehiro; Yako, Hideji; Tateno, Kozue; Hasegawa, Rumi; Takigami, Shu; Ohsako, Shunji; Yashiro, Takashi; Kato, Takako; Kato, Yukio

2016-02-01

Among heterogeneous S100β-protein-positive (S100β-positive) cells, star-like cells with extended cytoplasmic processes, the so-called folliculo-stellate cells, envelop hormone-producing cells or interconnect homophilically in the anterior pituitary. S100β-positive cells are known, from immunohistochemistry, to emerge from postnatal day (P) 10 and to proliferate and migrate in the parenchyma of the anterior pituitary with growth. Recent establishment of S100β-GFP transgenic rats expressing specifically green fluorescent protein (GFP) under the control of the S100β-promoter has allowed us to observe living S100β-positive cells. In the present study, we first confirmed that living S100β-positive cells in tissue cultures of S100β-GFP rat pituitary at P5 were present prior to P10 by means of confocal laser microscopy and that they proliferated and extended their cytoplasmic processes. Second, we examined the expression of the Snail-family zinc-finger transcription factors, Snail and Slug, to investigate the mechanism behind the morphological changes and the proliferation of S100β-positive cells. Interestingly, we detected Slug expression in S100β-positive cells and its increase together with development in the anterior pituitary. To analyze downstream of SLUG in S100β-positive cells, we utilized specific small interfering RNA for Slug mRNAs and observed that the expression of matrix metalloprotease (Mmp) 9, Mmp14 and chemokine Cxcl12 was down-regulated and that morphological changes and proliferation were decreased. Thus, our findings suggest that S100β-positive cells express Slug and that its expression is important for subsequent migration and proliferation.

Lipocalin-2 inhibits osteoclast formation by suppressing the proliferation and differentiation of osteoclast lineage cells

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

Kim, Hyun-Ju, E-mail: biohjk@knu.ac.kr; Yoon, Hye-Jin; Yoon, Kyung-Ae

Lipocalin-2 (LCN2) is a member of the lipocalin superfamily and plays a critical role in the regulation of various physiological processes, such as inflammation and obesity. In this study, we report that LCN2 negatively modulates the proliferation and differentiation of osteoclast precursors, resulting in impaired osteoclast formation. The overexpression of LCN2 in bone marrow-derived macrophages or the addition of recombinant LCN2 protein inhibits the formation of multinuclear osteoclasts. LCN2 suppresses macrophage colony-stimulating factor (M-CSF)-induced proliferation of osteoclast precursor cells without affecting their apoptotic cell death. Interestingly, LCN2 decreases the expression of the M-CSF receptor, c-Fms, and subsequently blocks its downstreammore » signaling cascades. In addition, LCN2 inhibits RANKL-induced osteoclast differentiation and attenuates the expression of c-Fos and nuclear factor of activated T cells c1 (NFATc1), which are important modulators in osteoclastogenesis. Mechanistically, LCN2 inhibits NF-κB signaling pathways, as demonstrated by the suppression of IκBα phosphorylation, nuclear translocation of p65, and NF-κB transcriptional activity. Thus, LCN2 is an anti-osteoclastogenic molecule that exerts its effects by retarding the proliferation and differentiation of osteoclast lineage cells. - Highlights: • LCN2 expression is regulated during osteoclast development. • LCN2 suppresses M-CSF-mediated osteoclast precursor proliferation. • LCN2 inhibits RANKL-induced osteoclast differentiation.« less

Impact of blue LED irradiation on proliferation and gene expression of cultured human keratinocytes

NASA Astrophysics Data System (ADS)

Becker, Anja; Sticht, Carsten; Dweep, Harsh; van Abeelen, Frank A.; Gretz, Norbert; Oversluizen, Gerrit

2015-03-01

Blue light is known for its anti-microbial, anti-proliferative and anti-inflammatory effects. Furthermore, it is already used for the treatment of neonatal jaundice and acne. However, little is known about the exact mechanisms of action on gene expression level. The aim of this study was to assess the impact of blue LED irradiation on the proliferation and gene expression in immortalized human keratinocytes (HaCaT) in vitro. Furthermore its safety was assessed. XTT-tests revealed a decrease in cell proliferation in blue light irradiated cells depending on the duration of light irradiation. Moreover, gene expression analysis demonstrated deregulated genes already 3 hours after blue light irradiation. 24 hours after blue light irradiation the effects seemed to be even more pronounced. The oxidative stress response was significantly increased, pointing to increased ROS production due to blue light, as well as steroid hormone biosynthesis. Downregulated pathways or biological processes were connected to anti-inflammatory response. Interestingly, also the melanoma pathway contained significantly downregulated genes 24 hours after blue light irradiation, which stands in accordance to literature that blue light can also inhibit proliferation in cancer cells. First tests with melanoma cells revealed a decrease in cell proliferation after blue light irradiation. In conclusion, blue light irradiation might open avenues to new therapeutic regimens; at least blue light seems to have no effect that induces cancer growth or formation.

MS4a4B, a CD20 homologue in T cells, inhibits T cell propagation by modulation of cell cycle.

PubMed

Xu, Hui; Yan, Yaping; Williams, Mark S; Carey, Gregory B; Yang, Jingxian; Li, Hongmei; Zhang, Guang-Xian; Rostami, Abdolmohamad

2010-11-01

MS4a4B, a CD20 homologue in T cells, is a novel member of the MS4A gene family in mice. The MS4A family includes CD20, FcεRIβ, HTm4 and at least 26 novel members that are characterized by their structural features: with four membrane-spanning domains, two extracellular domains and two cytoplasmic regions. CD20, FcεRIβ and HTm4 have been found to function in B cells, mast cells and hematopoietic cells respectively. However, little is known about the function of MS4a4B in T cell regulation. We demonstrate here that MS4a4B negatively regulates mouse T cell proliferation. MS4a4B is highly expressed in primary T cells, natural killer cells (NK) and some T cell lines. But its expression in all malignant T cells, including thymoma and T hybridoma tested, was silenced. Interestingly, its expression was regulated during T cell activation. Viral vector-driven overexpression of MS4a4B in primary T cells and EL4 thymoma cells reduced cell proliferation. In contrast, knockdown of MS4a4B accelerated T cell proliferation. Cell cycle analysis showed that MS4a4B regulated T cell proliferation by inhibiting entry of the cells into S-G2/M phase. MS4a4B-mediated inhibition of cell cycle was correlated with upregulation of Cdk inhibitory proteins and decreased levels of Cdk2 activity, subsequently leading to inhibition of cell cycle progression. Our data indicate that MS4a4B negatively regulates T cell proliferation. MS4a4B, therefore, may serve as a modulator in the negative-feedback regulatory loop of activated T cells.

Incorporation of diffusion-weighted magnetic resonance imaging data into a simple mathematical model of tumor growth

NASA Astrophysics Data System (ADS)

Atuegwu, N. C.; Colvin, D. C.; Loveless, M. E.; Xu, L.; Gore, J. C.; Yankeelov, T. E.

2012-01-01

We build on previous work to show how serial diffusion-weighted MRI (DW-MRI) data can be used to estimate proliferation rates in a rat model of brain cancer. Thirteen rats were inoculated intracranially with 9L tumor cells; eight rats were treated with the chemotherapeutic drug 1,3-bis(2-chloroethyl)-1-nitrosourea and five rats were untreated controls. All animals underwent DW-MRI immediately before, one day and three days after treatment. Values of the apparent diffusion coefficient (ADC) were calculated from the DW-MRI data and then used to estimate the number of cells in each voxel and also for whole tumor regions of interest. The data from the first two imaging time points were then used to estimate the proliferation rate of each tumor. The proliferation rates were used to predict the number of tumor cells at day three, and this was correlated with the corresponding experimental data. The voxel-by-voxel analysis yielded Pearson's correlation coefficients ranging from -0.06 to 0.65, whereas the region of interest analysis provided Pearson's and concordance correlation coefficients of 0.88 and 0.80, respectively. Additionally, the ratio of positive to negative proliferation values was used to separate the treated and control animals (p <0.05) at an earlier point than the mean ADC values. These results further illustrate how quantitative measurements of tumor state obtained non-invasively by imaging can be incorporated into mathematical models that predict tumor growth.

The bioactive effects of casein proteins on enteroendocrine cell health, proliferation and incretin hormone secretion.

PubMed

Gillespie, Anna L; Green, Brian D

2016-11-15

Previous studies suggest that casein exerts various anti-diabetic effects. However, it is not known which casein proteins are bioactive, nor their effects on enteroendocrine cells. This study evaluated the effects of intact whole casein, intact individual proteins (alpha, beta and kappa casein) and hydrolysates on an enteroendocrine cell line. High content analysis accurately monitored changes in cell health and intracellular glucagon-like peptide-1 (GLP-1) content. Cheese ripening duration and GLP-1 secretory responses were also considered. Beta casein significantly stimulated enteroendocrine cell proliferation and all caseins were potent GLP-1 secretagogues (except kappa casein). Interestingly the GLP-1 secretory activity was almost always lost or significantly reduced upon hydrolysis with proteolytic enzymes. Only pepsin-derived beta casein hydrolysates had significantly increased potency compared with the intact protein, but this was diminished with prolonged hydrolysis. In conclusion casein proteins are not detrimental to enteroendocrine cells, and alpha and beta casein are particularly beneficial stimulating proliferation and GLP-1 secretion. Copyright © 2016 Elsevier Ltd. All rights reserved.

Balanced cell proliferation and expansion is essential for flowering stem growth control.

PubMed

Ferjani, Ali; Hanai, Kenya; Gunji, Shizuka; Maeda, Saori; Sawa, Shinichiro; Tsukaya, Hirokazu

2015-01-01

The postembryonic development of aboveground plant organs relies on a continuous supply of cells from the shoot apical meristem. Previous studies of developmental regulation in leaves and flowers have revealed the crucial role of coordinated cell proliferation and differentiation during organogenesis. However, the importance of this coordination has not been examined in flowering stems. Very recently, we attempted to identify regulatory factors that maintain flowering stem integrity. We found that the increased cell number in clavata (clv) mutants and the decreased cell size in de-etiolated (det)3-1 resulted in flowering stems that were thicker and thinner, respectively, than in wild-type (WT) plants. Interestingly, in the cell proliferation- and cell expansion-defective double mutant clv det3-1, the flowering stems often exhibited severe cracking, resulting in exposure of their inner tissues. In this study, further quantification of the cellular phenotypes in the cotyledons and leaves revealed no differences between det3-1 and clv3 det3-1. Together, the above findings suggest that the clv3 mutation in a det3-1 background primarily affects flowering stems, while its effect on other organs is likely negligible. We propose that the coordination between cell proliferation and differentiation is not only important during leaf development, but also plays a role in the growth control of Arabidopsis flowering stems.

The Tangled Circuitry of Metabolism and Apoptosis

PubMed Central

Andersen, Joshua L.; Kornbluth, Sally

2013-01-01

For single cell organisms, nutrient uptake and metabolism are at the crux of their most basic decision of whether to grow or divide. In metazoans, cell fate decisions are more complex: organismal homeostasis must be strictly maintained by balancing cell proliferation and death. Despite this increased complexity, cell fate within multicellular organisms is also influenced by metabolism; recent studies, triggered in part be an interest tumor metabolism, are beginning to illuminate the mechanisms through which proliferation, death, and metabolism are intertwined. In particular, work on Bcl-2 family proteins suggests that the signaling pathways governing metabolism and apoptosis are inextricably linked. Here, we review the crosstalk between these pathways, emphasizing recent work that illustrates the emerging dual nature of several core apoptotic proteins in regulating both metabolism and cell death. PMID:23395270

The tangled circuitry of metabolism and apoptosis.

PubMed

Andersen, Joshua L; Kornbluth, Sally

2013-02-07

For single-cell organisms, nutrient uptake and metabolism are central to the fundamental decision of whether to grow or divide. In metazoans, cell fate decisions are more complex: organismal homeostasis must be strictly maintained by balancing cell proliferation and death. Despite this increased complexity, cell fate within multicellular organisms is also influenced by metabolism; recent studies, triggered in part by an interest in tumor metabolism, are beginning to illuminate the mechanisms through which proliferation, death, and metabolism are intertwined. In particular, work on Bcl-2 family proteins suggests that the signaling pathways governing metabolism and apoptosis are inextricably linked. Here we review the crosstalk between these pathways, emphasizing recent work that illustrates the emerging dual nature of several core apoptotic proteins in regulating both metabolism and cell death. Copyright © 2013 Elsevier Inc. All rights reserved.

Human epidermal langerhans cells express the immunoregulatory enzyme indoleamine 2,3-dioxygenase.

PubMed

von Bubnoff, Dagmar; Bausinger, Huguette; Matz, Heike; Koch, Susanne; Häcker, Georg; Takikawa, Osamu; Bieber, Thomas; Hanau, Daniel; de la Salle, Henri

2004-08-01

Langerhans cells (LC) are a special subset of dendritic cells integrating cutaneous immunity. The study of LC function is of major interest not only for efforts of vaccine design and immunotherapy but also for gaining an insight into the pathogenesis of immune-mediated cutaneous diseases and neoplasias. Recently, defined antigen-presenting cells were described that express indoleamine 2,3-dioxygenase (IDO) and inhibit T cell proliferation in vitro and in vivo. Here, we show that stimulation with interferon-gamma (IFN-gamma) induces the expression of functionally active IDO in highly purified human epidermal LC. The induction of IDO after stimulation of LC with IFN-gamma seems to follow a defined kinetic with rapid upregulation followed by a downregulation after about 24 h of culture. Accordingly, proliferation of T cells induced by anti-CD3 antibodies was modulated by supernatants of IFN-gamma-activated human epidermal LC. Importantly, downregulation of T cell proliferation by supernatants of 24 h IFN-gamma-activated LC was prevented by inhibition of IDO. These results indicate that LC not only have the capacity to stimulate but also to inhibit T cells, and suggest that LC possess an immunoregulatory function in promoting T cell tolerance by production of IDO.

N-acetyl-L-cysteine increases MnSOD activity and enhances the recruitment of quiescent human fibroblasts to the proliferation cycle during wound healing

PubMed Central

Mao, Gaowei; Goswami, Monali; Kalen, Amanda L.; Goswami, Prabhat C.; Sarsour, Ehab H.

2016-01-01

Background The rebuilding of the connective tissue during wound healing requires the recruitment of fibroblasts to the wound area as well as reentry of quiescent fibroblasts to the proliferative cycle. Whether this process can be modulated by a small molecular weight thiol antioxidant N-acetyl-L-cysteine (NAC) was tested in normal human skin fibroblasts (NHFs) in this study. Methods and Results By using a uni-directional wound healing assay, NAC treated cells demonstrated a decreased migration rate but increased number of proliferating cells recruited into the wound area post wounding. Fifteen day quiescent control and NAC treated NHFs were re-plated at a lower density and cell numbers counted at different days post-plating. Interestingly, NAC treated cells exhibited increased cellular proliferation indicated by both decreased cell population doubling time and increased S phase cells. NAC treated cells demonstrated decreased steady state levels of reactive oxygen species as well as increased protein and activity levels of manganese superoxide dismutase (MnSOD). NAC treatment failed to induce proliferation in quiescent cells lacking MnSOD expression. Conclusions These results demonstrate that NAC enhanced the recruitment of quiescent NHFs into proliferation cycle during wound healing. Our results also suggest that the wound healing properties of NAC might be due to its ability to induce and enhance MnSOD expression and activity. Altogether, these findings suggest NAC might be potentially developed as a dietary intervention to improve tissue injury in animals and humans. PMID:26671656

Differential effects of culture senescence and mechanical stimulation on the proliferation and leiomyogenic differentiation of MSC from different sources: implications for engineering vascular grafts.

PubMed

Koobatian, Maxwell T; Liang, Mao-Shih; Swartz, Daniel D; Andreadis, Stelios T

2015-04-01

We examined the effects of senescence on the proliferation and leiomyogenic differentiation potential of mesenchymal stem cells (MSCs) isolated from bone marrow (BM-MSCs) or hair follicles (HF-MSCs). To this end, we compared ovine HF-MSCs and BM-MSCs in terms of their proliferation and differentiation potential to the smooth muscle cell lineage. We discovered that HF-MSCs are less susceptible to culture senescence compared with BM-MSCs. We hypothesized that application of mechanical forces may enhance the contractility and mechanical properties of vascular constructs prepared from senescent MSCs. Interestingly, HF-MSCs and BM-MSCs responded differently to changes in the mechanical microenvironment, suggesting that despite phenotypic similarities, MSCs from different anatomic locations may activate different pathways in response to the same microenvironmental factors. In turn, this may also suggest that cell-based tissue regeneration approaches may need to be tailored to the stem cell origin, donor age, and culture time for optimal results.

Poly(1,3-propylene sebacate) and Poly(sebacoyl diglyceride): A Pair of Potential Polymers for the Proliferation and Differentiation of Retinal Progenitor Cells.

PubMed

Ni, Ni; Ji, Jing; Chen, Shuo; Zhang, Dandan; Wang, Zi; Shen, Bingqiao; Guo, Chunyu; Zhang, Yi; Wang, Shaofei; Fan, Xianqun; You, Zhengwei; Luo, Min; Gu, Ping

2016-09-01

Using suitable polymers as a carrier for growing and delivering retinal progenitor cells (RPCs) is a promising therapeutic strategy in retinal cell-replacement therapy. Herein recently developed polymer, poly(sebacoyl diglyceride) (PSeD), is selected and its nonhydroxylized counterpart poly(1,3-propylene sebacate) (PPS) is designed to evaluate their potentials for RPC growth and future RPC application. The structures and mechanical properties of the polymers are characterized. The cytocompatibility and effects of these polymers on RPC proliferation, differentiation, and migration are systematically investigated in vitro. Our data show that PPS and PSeD display excellent cytocompatibility with low expression of inflammation and apoptosis factors, which benefit RPC growth. In proliferation assays reveal that RPCs expands well on the polymers, but PPS performs the best for RPC expansion, indicating that PPS can remarkably promote RPC proliferation. In differentiation conditions, RPCs grown on PSeD are more likely to differentiate toward retinal neurons, including photoreceptors, the most interesting type of cells for retinal cell-replacement therapy. Additionally, our results demonstrate that RPCs grown on PSeD display an outstanding ability to migrate. In conclusion, PPS can markedly promote RPC proliferation, whereas PSeD can enhance RPC differentiation toward retinal neurons, suggesting that PSeD and PPS have potential applications in future retinal cell-replacement therapies. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cytotoxic effect of a family of peroxisome proliferator-activated receptor antagonists in colorectal and pancreatic cancer cell lines.

PubMed

Ammazzalorso, Alessandra; De Lellis, Laura; Florio, Rosalba; Bruno, Isabella; De Filippis, Barbara; Fantacuzzi, Marialuigia; Giampietro, Letizia; Maccallini, Cristina; Perconti, Silvia; Verginelli, Fabio; Cama, Alessandro; Amoroso, Rosa

2017-11-01

Recent studies report an interesting role of peroxisome proliferator-activated receptor (PPAR) antagonists in different tumor models, being these compounds able to perturb metabolism and viability in cancer cells. In this work, the identification of a novel PPAR antagonist, showing inhibitory activity on PPARα and a weaker antagonism on PPARγ, is described. The activity of this compound and of a series of chemical analogues was investigated in selected tumor cell lines, expressing both PPARα and PPARγ. Data obtained show a dose-dependent cytotoxic effect of the novel PPAR antagonist in colorectal and pancreatic cancer models. © 2017 John Wiley & Sons A/S.

Pirfenidone Inhibits T Cell Activation, Proliferation, Cytokine and Chemokine Production, and Host Alloresponses

PubMed Central

Visner, Gary A.; Liu, Fengzhi; Bizargity, Peyman; Liu, Hanzhong; Liu, Kaifeng; Yang, Jun; Wang, Liqing; Hancock, Wayne W.

2009-01-01

Background We previously showed that pirfenidone, an anti-fibrotic agent, reduces lung allograft injury/rejection. In this study, we tested the hypothesis that pirfenidone has immune modulating activities and evaluated its effects on the function of T cell subsets, which play important roles in allograft rejection. Method We first evaluated whether pirfenidone alters T cell proliferation and cytokine release in response to T cell receptor (TCR) activation, and whether pirfenidone alters regulatory T cells (CD4+CD25+) suppressive effects using an in vitro assay. Additionally, pirfenidone effects on alloantigen-induced T cell proliferation in vivo were assessed by adoptive transfer of CFSE-labeled T cells across a parent->F1 MHC mismatch, as well as using a murine heterotopic cardiac allograft model (BALB/c->C57BL/6). Results Pirfenidone was found to inhibit the responder frequency of TCR-stimulated CD4+ cell total proliferation in vitro and in vivo, whereas both CD4 and CD8 proliferation index were reduced by pirfenidone. Additionally, pirfenidone inhibited TCR-induced production of multiple pro-inflammatory cytokines and chemokines. Interestingly, there was no change on TGF-β production by purified T cells, and pirfenidone had no effect on the suppressive properties of naturally occurring regulatory T cells. Pirfenidone alone showed a small but significant (p < 0.05) effect on the in vivo allogeneic response while the combination of pirfenidone and low dose rapamycin had more remarkable effect in reducing the alloantigen response with prolonged graft survival. Conclusion Pirfenidone may be an important new agent in transplantation, with particular relevance to combating chronic rejection by inhibiting both fibroproliferative and alloimmune responses. PMID:19667934

Inositol synthesis regulates activation of GSK-3α in neuronal cells

PubMed Central

Ye, Cunqi; Greenberg, Miriam L.

2015-01-01

The synthesis of inositol provides precursors of inositol lipids and inositol phosphates that are pivotal for cell signaling. Mood-stabilizers lithium and valproic acid (VPA), used for treating bipolar disorder, cause cellular inositol depletion, which has been proposed as a therapeutic mechanism of action of both drugs. Despite the importance of inositol, the requirement for inositol synthesis in neuronal cells is not well understood. Here, we examined inositol effects on proliferation of SK-N-SH neuroblastoma cells. The essential role of inositol synthesis in proliferation is underscored by the findings that exogenous inositol was dispensable for proliferation, and inhibition of inositol synthesis decreased proliferation. Interestingly, the inhibition of inositol synthesis by knocking down INO1, which encodes inositol-3-phosphate synthase, the rate-limiting enzyme of inositol synthesis, led to inactivation of GSK-3α by increasing the inhibitory phosphorylation of this kinase. Similarly, the mood-stabilizer VPA effected transient decreases in intracellular inositol, leading to inactivation of GSK-3α. As GSK-3 inhibition has been proposed as a likely therapeutic mechanism of action, the finding that inhibition of inositol synthesis results in inactivation of GSK-3α suggests a unifying hypothesis for mechanism of mood-stabilizing drugs. PMID:25345501

Effect of Water-Glass Coating on HA and HA-TCP Samples for MSCs Adhesion, Proliferation, and Differentiation.

PubMed

Bajpai, Indu; Kim, Duk Yeon; Kyong-Jin, Jung; Song, In-Hwan; Kim, Sukyoung

2016-01-01

Ca-P and silicon based materials have become very popular as bone tissue engineering materials. In this study, water-glass (also known as sodium silicate glass) was coated on sintered hydroxyapatite (HA) and HA-TCP (TCP stands for tricalcium phosphate) samples and subsequently heat-treated at 600°C for 2 hrs. X-rays diffraction showed the presence of β- and α-TCP phases along with HA in the HA-TCP samples. Samples without coating, with water-glass coating, and heat-treated after water-glass coating were used to observe the adhesion and proliferation response of bone marrow derived-mesenchymal stem cells (MSCs). Cell culture was carried out for 4 hrs, 1 day, and 7 days. Interestingly, all samples showed similar response for cell adhesion and proliferation up to 7-day culture but fibronectin, E-cadherin, and osteogenic differentiation related genes (osteocalcin and osteopontin) were significantly induced in heat-treated water-glass coated HA-TCP samples. A water-glass coating on Ca-P samples was not found to influence the cell proliferation response significantly but activated some extracellular matrix genes and induced osteogenic differentiation in the MSCs.

MicroRNA-494 inhibits cell proliferation and invasion of chondrosarcoma cells in vivo and in vitro by directly targeting SOX9.

PubMed

Li, Jingyuan; Wang, Lijuan; Liu, Zongzhi; Zu, Chao; Xing, Fanfan; Yang, Pei; Yang, Yongkang; Dang, Xiaoqian; Wang, Kunzheng

2015-09-22

Accumulating evidence indicates that dysregulation of miRNAs could contribute to tumor growth and metastasis of chondrosarcoma by infuencing cell proliferation and invasion. In the current study, we are interested to examine the role of miRNAs in the carcinogenesis and progression of chondrosarcoma. Here, using comparative miRNA profiling of tissues and cells of chondrosarcoma and cartilage, we identified miR-494 as a commonly downregulated miRNA in the tissues of patients with chondrosarcoma and chondrosarcoma cancer cell line, and upregulation of miR-494 could inhibit proliferation and invasion of chondrosarcoma cancer cells in vivo and in vitro. Moreover, our data demonstrated that SOX9, the essential regulator of the process of cartilage differentiation, was the direct target and functional mediator of miR-494 in chondrosarcoma cells. And downregulation of SOX9 could also inhibit migration and invasion of chondrosarcoma cells. In the last, we identified low expression of miR-494 was significantly correlated with poor overall survival and prognosis of chondrosarcoma patients. Thus, miR-494 may be a new common therapeutic target and prognosis biomarker for chondrosarcoma.

MiR-300 suppresses laryngeal squamous cell carcinoma proliferation and metastasis by targeting ROS1.

PubMed

Ge, Wensheng; Han, Chaodong; Wang, Jing; Zhang, Yunping

2016-01-01

Laryngeal squamous cell carcinoma (LSCC) is a common aggressive head and neck cancer with high mortality and incidence. MicroRNAs (miRNAs) are short, non-coding and endogenous RNAs that posttranscriptionally inhibit gene expression. In this study, we showed that miR-300 expression was downregulated in LSCC tissues compared with adjacent no-tumor tissues. MiR-300 overexpression inhibited Hep-2 cell proliferation, as well as the expression of ki-67 and PCNA. Moreover, overexpression of miR-300 repressed the cell invasion in Hep-2 cells. We identified c-ros oncogene 1 receptor tyrosine kinase (ROS1) as a direct target gene of miR-300 in Hep-2 cell. Furthermore, ROS1 expression was upregulated in LSCC tissues compared with adjacent no-tumor tissues. Interesting, there were an inverse correlation between ROS1 and miR-300 expression in the LSCC tissues. Overexpression of ROS1 increased the Hep-2 cells proliferation and invasion. Overexpression of ROS1 abrogated miR-300 induced cell growth and invasion inhibition. Therefore, our data suggested that miR-300 acted as a tumor suppressive gene in LSCC.

MiR-300 suppresses laryngeal squamous cell carcinoma proliferation and metastasis by targeting ROS1

PubMed Central

Ge, Wensheng; Han, Chaodong; Wang, Jing; Zhang, Yunping

2016-01-01

Laryngeal squamous cell carcinoma (LSCC) is a common aggressive head and neck cancer with high mortality and incidence. MicroRNAs (miRNAs) are short, non-coding and endogenous RNAs that posttranscriptionally inhibit gene expression. In this study, we showed that miR-300 expression was downregulated in LSCC tissues compared with adjacent no-tumor tissues. MiR-300 overexpression inhibited Hep-2 cell proliferation, as well as the expression of ki-67 and PCNA. Moreover, overexpression of miR-300 repressed the cell invasion in Hep-2 cells. We identified c-ros oncogene 1 receptor tyrosine kinase (ROS1) as a direct target gene of miR-300 in Hep-2 cell. Furthermore, ROS1 expression was upregulated in LSCC tissues compared with adjacent no-tumor tissues. Interesting, there were an inverse correlation between ROS1 and miR-300 expression in the LSCC tissues. Overexpression of ROS1 increased the Hep-2 cells proliferation and invasion. Overexpression of ROS1 abrogated miR-300 induced cell growth and invasion inhibition. Therefore, our data suggested that miR-300 acted as a tumor suppressive gene in LSCC. PMID:27725869

MicroRNA-494 inhibits cell proliferation and invasion of chondrosarcoma cells in vivo and in vitro by directly targeting SOX9

PubMed Central

Liu, Zongzhi; Zu, Chao; Xing, Fanfan; Yang, Pei; Yang, Yongkang; Dang, Xiaoqian; Wang, Kunzheng

2015-01-01

Accumulating evidence indicates that dysregulation of miRNAs could contribute to tumor growth and metastasis of chondrosarcoma by infuencing cell proliferation and invasion. In the current study, we are interested to examine the role of miRNAs in the carcinogenesis and progression of chondrosarcoma. Here, using comparative miRNA profiling of tissues and cells of chondrosarcoma and cartilage, we identified miR-494 as a commonly downregulated miRNA in the tissues of patients with chondrosarcoma and chondrosarcoma cancer cell line, and upregulation of miR-494 could inhibit proliferation and invasion of chondrosarcoma cancer cells in vivo and in vitro. Moreover, our data demonstrated that SOX9, the essential regulator of the process of cartilage differentiation, was the direct target and functional mediator of miR-494 in chondrosarcoma cells. And downregulation of SOX9 could also inhibit migration and invasion of chondrosarcoma cells. In the last, we identified low expression of miR-494 was significantly correlated with poor overall survival and prognosis of chondrosarcoma patients. Thus, miR-494 may be a new common therapeutic target and prognosis biomarker for chondrosarcoma. PMID:26317788

Myeloid-Derived Suppressor Cells Are Involved in Lysosomal Acid Lipase Deficiency-Induced Endothelial Cell Dysfunctions

PubMed Central

Zhao, Ting; Ding, Xinchun; Du, Hong; Yan, Cong

2014-01-01

The underlying mechanisms that lysosomal acid lipase (LAL) deficiency causes infiltration of myeloid-derived suppressor cells (MDSCs) in multiple organs and subsequent inflammation remain incompletely understood. Endothelial cells (ECs), lining the inner layer of blood vessels, constitute barriers regulating leukocytes transmigration to the site of inflammation. Therefore, we hypothesized that ECs are dysfunctional in LAL-deficient (lal−/−) mice. We found that Ly6G+ cells transmigrated more efficiently across lal−/− ECs than wild-type (lal+/+) ECs, which was associated with increased level of platelet endothelial cell adhesion molecule-1 (PECAM-1) and monocyte chemoattractant protein-1 (MCP-1) in lal−/− ECs. In addition, lal−/−ECs showed enhanced migration and proliferation, decreased apoptosis, but impaired tube formation and angiogenesis. lal−/− ECs also suppressed T cell proliferation in vitro. Interestingly, lal−/− Ly6G+ cells promoted in vivo angiogenesis (including a tumor model), EC tube formation and proliferation. Finally, the mammalian target of rapamycin (mTOR) pathway was activated in lal−/− ECs, and inhibition of mTOR reversed EC dysfunctions, including decreasing Ly6G+ cell transmigration, delaying migration, and relieving suppression of T cell proliferation, which was mediated by decreasing production of reactive oxygen species (ROS). Our results indicate that LAL regulates EC functions through interaction with MDSCs and modulation of the mTOR pathway, which may provide a mechanistic basis for targeting MDSCs or mTOR to rejuvenate EC functions in LAL-deficiency related diseases. PMID:25000979

Different effects of 25-kDa amelogenin on the proliferation, attachment and migration of various periodontal cells

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

Li, Xiting; Shu, Rong, E-mail: shurong123@hotmail.com; Liu, Dali

Previous studies have assumed that amelogenin is responsible for the therapeutic effect of the enamel matrix derivative (EMD) in periodontal tissue healing and regeneration. However, it is difficult to confirm this hypothesis because both the EMD and the amelogenins are complex mixtures of multiple proteins. Further adding to the difficulties is the fact that periodontal tissue regeneration involves various types of cells and a sequence of associated cellular events including the attachment, migration and proliferation of various cells. In this study, we investigated the potential effect of a 25-kDa recombinant porcine amelogenin (rPAm) on primarily cultured periodontal ligament fibroblasts (PDLF),more » gingival fibroblasts (GF) and gingival epithelial cells (GEC). The cells were treated with 25-kDa recombinant porcine amelogenin at a concentration of 10 {mu}g/mL. We found that rPAm significantly promoted the proliferation and migration of PDLF, but not their adhesion. Similarly, the proliferation and adhesion of GF were significantly enhanced by treatment with rPAm, while migration was greatly inhibited. Interestingly, this recombinant protein inhibited the growth rate, cell adhesion and migration of GEC. These data suggest that rPAm may play an essential role in periodontal regeneration through the activation of periodontal fibroblasts and inhibition of the cellular behaviors of gingival epithelial cells.« less

Melittin induces PTCH1 expression by down-regulating MeCP2 in human hepatocellular carcinoma SMMC-7721 cells

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

Wu, Xiaoqin; Zhao, Bin; Cheng, Yahui

Hepatocellular carcinoma (HCC) has a high mortality rate worldwide and still remains to be a noticeable public health problem. Therefore, new remedies are urgently needed. Melittin, a major component of bee venom, is known to suppress cell growth in various cancers including HCC. However, the mechanism of the anticancer effect of melittin on HCC has not been fully elucidated. It has been reported that Methyl-CpG binding protein 2 (MeCP2) plays a key role in tumor proliferation, apoptosis, migration and invasion. In the present study, we found the high expression of MeCP2 in human HCC tissues and in the SMMC-7721 cellmore » line. MeCP2 silencing inhibited cell proliferation, while over-expression of MeCP2 promoted cell growth in SMMC-7721 cells. It indicates that MeCP2 may be an attractive target for human HCC. We further found that melittin could inhibit cell proliferation by reducing MeCP2 expression in vitro. Interestingly, the inhibitory effect of melittin on cell proliferation was due to a delay in G{sub 0}/G{sub 1} cell cycle progression, without influencing cell apoptosis. Next, we investigated the potential molecular mechanisms and found that MeCP2 could modulate Shh signaling in SMMC-7721 cells. Further study indicates that melittin may induce the demethylation of PTCH1 promoter, resulting in the increased expression of PTCH1. Furthermore, the expression of Shh and GLI1 was significantly lowered upon treatment of melittin. These results suggest that melittin can block Shh signaling in vitro. In short, these results indicate that melittin inhibits cell proliferation by down-regulating MeCP2 through Shh signaling in SMMC-7721 cells. - Highlights: • MeCP2 plays a key role in the proliferation of human HCC cells. • Melittin reduces MeCP2 expression in vitro. • Melittin induces G{sub 0}/G{sub 1} cell cycle arrest in SMMC-7721 cells. • MeCP2 modulates the Shh signaling pathway in SMMC-7721 cells. • Melittin blocks the Shh signaling pathway in SMMC-7721 cells.« less

CD1d-dependent expansion of NKT follicular helper cells in vivo and in vitro is a product of cellular proliferation and differentiation.

PubMed

Rampuria, Pragya; Lang, Mark L

2015-05-01

NKT follicular helper cells (NKTfh cells) are a recently discovered functional subset of CD1d-restricted NKT cells. Given the potential for NKTfh cells to promote specific antibody responses and germinal center reactions, there is much interest in determining the conditions under which NKTfh cells proliferate and/or differentiate in vivo and in vitro. We confirm that NKTfh cells expressing the canonical semi-invariant Vα14 TCR were CXCR5(+)/ICOS(+)/PD-1(+)/Bcl6(+) and increased in number following administration of the CD1d-binding glycolipid α-galactosylceramide (α-GC) to C57Bl/6 mice. We show that the α-GC-stimulated increase in NKTfh cells was CD1d-dependent since the effect was diminished by reduced CD1d expression. In vivo and in vitro treatment with α-GC, singly or in combination with IL-2, showed that NKTfh cells increased in number to a greater extent than total NKT cells, but proliferation was near-identical in both populations. Acquisition of the NKTfh phenotype from an adoptively transferred PD-1-depleted cell population was also evident, showing that peripheral NKT cells differentiated into NKTfh cells. Therefore, the α-GC-stimulated, CD1d-dependent increase in peripheral NKTfh cells is a result of cellular proliferation and differentiation. These findings advance our understanding of the immune response following immunization with CD1d-binding glycolipids. © The Japanese Society for Immunology. 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Prevalence of 5-lipoxygenase expression in canine osteosarcoma and the effects of a dual 5-lipoxygenase/cyclooxygenase inhibitor on osteosarcoma cells in vitro and in vivo.

PubMed

Goupil, R C; Bushey, J J; Peters-Kennedy, J; Wakshlag, J J

2012-09-01

Canine osteosarcoma is an insidious disease with few effective treatment modalities; therefore, use of pharmacologic intervention to improve mortality or morbidity is constantly sought. The use of cyclooxygenase enzyme inhibitors has been an area of interest with limited efficacy based on retrospective examination of tumor expression and in vivo cell proliferation models. Recently, examination of dual cyclooxygenase and 5-lipoxygenase inhibitors in human and canine oncology suggests that 5-lipoxygenase inhibitors may be an effective approach in vitro and during tumor induction in rodent models. Therefore, the authors decided to examine 5-lipoxygenase expression in primary canine osteosarcoma samples and have shown that approximately 65% of osteosarcomas label positive for cytoplasmic 5-lipoxygenase. Further examination of a cell culture and xenograft model shows similar 5-lipoxygenase expression. Surprisingly, a canine 5-lipoxygenase inhibitor (tepoxalin) significantly reduced cell proliferation at physiologic doses in vitro and diminished xenograft tumor growth in nude mice, suggesting that further investigation is needed. Traditionally, 5-lipoxygense leads to production of lipid mediators, such as leukotriene B(4) and 5-oxo-eicosatetraenoic acid, which, when added back to the media of tepoxalin-treated cells, did not recover cell proliferation. The lack of nuclear staining in primary and xenografted tumors and the lack of response to eicoasanoids suggest that lipid mediator production is not the primary means by which tepoxalin acts to alter proliferation. Regardless of the mechanisms involved in retarding cell proliferation, future investigation is warranted.

Type II cGMP‑dependent protein kinase inhibits the migration, invasion and proliferation of several types of human cancer cells.

PubMed

Wu, Min; Wu, Yan; Qian, Hai; Tao, Yan; Pang, Ji; Wang, Ying; Chen, Yongchang

2017-10-01

Previous studies have indicated that type II cyclic guanosine monophosphate (cGMP)‑dependent protein kinase (PKG II) could inhibit the proliferation and migration of gastric cancer cells. However, the effects of PKG II on the biological functions of other types of cancer cells remain to be elucidated. Therefore, the aim of the present study was to investigate the effects of PKG II on cancer cells derived from various types of human tissues, including A549 lung, HepG2 hepatic, OS‑RC‑2 renal, SW480 colon cancer cells and U251 glioma cells. Cancer cells were infected with adenoviral constructs coding PKG II (Ad‑PKG II) to up‑regulate PKG II expression, and treated with 8‑(4‑chlorophenylthio) (8‑pCPT)‑cGMP to activate the kinase. A Cell Counting kit 8 assay was used to detect cell proliferation. Cell migration was measured using a Transwell assay, whereas a terminal deoxynucleotidyl transferase 2'‑deoxyuridine, 5'‑triphosphate nick‑end labeling assay was used to detect cell apoptosis. A pull‑down assay was used to investigate the activation of Ras‑related C3 botulinum toxin substrate (Rac) 1 and western blotting was used to detect the expression of proteins of interest. The present results demonstrated that EGF (100 ng/ml, 24 h) promoted the proliferation and migration of cancer cells, and it suppressed their apoptosis. In addition, treatment with EGF enhanced the activation of Rac1, and up‑regulated the protein expression of proliferating cell nuclear antigen, matrix metalloproteinase (MMP)2, MMP7 and B‑cell lymphoma (Bcl)‑2, whereas it down‑regulated the expression of Bcl‑2‑associated X protein. Transfection of cancer cells with Ad‑PKG II, and PKG II activation with 8‑pCPT‑cGMP, was identified to counteract the effects triggered by EGF. The present results suggested that PKG II may exert inhibitory effects on the proliferation and migration of various types of cancer cells.

Potentiation of lymphocyte proliferative responses by nickel sulfide

NASA Technical Reports Server (NTRS)

Jaramillo, A.; Sonnenfeld, G.

1992-01-01

Crystalline nickel sulfide (NiS) induced a spleen cell proliferation that resembles a mixed lymphocyte reaction (MLR). It depended on cell-cell interaction, induced high levels of interleukin-1 (IL-1) and interleukin-2 (IL-2) and the responding cell subpopulation was composed of CD4+ T lymphocytes. Furthermore, the proliferation was inhibited in a dose-dependent manner by magnesium. Crystalline NiS also increased significantly the spleen cell proliferative response to concanavalin A (Con A) and lipopolysaccharide (LPS) with magnesium potentiating the combined effects of crystalline NiS and mitogens. Interestingly, crystalline NiS did not show any effect on the induction of IL-2 by Con A. The results described herein suggest that crystalline NiS can potentiate both antigenic (MLR) and mitogenic (Con A and LPS) proliferative responses in vitro. Crystalline NiS appears to potentiate these responses by acting in the form of ionic nickel on several intracellular targets for which magnesium ions have different noncompetitive interactions. The effects of magnesium on the potentiating action of crystalline NiS are different depending upon the type of primary stimulatory signal for proliferation (mitogenic or antigenic).

HB-EGF function in cardiac valve development requires interaction with heparan sulfate proteoglycans.

PubMed

Iwamoto, Ryo; Mine, Naoki; Kawaguchi, Taichiro; Minami, Seigo; Saeki, Kazuko; Mekada, Eisuke

2010-07-01

HB-EGF, a member of the EGF family of growth factors, plays an important role in cardiac valve development by suppressing mesenchymal cell proliferation. Here, we show that HB-EGF must interact with heparan sulfate proteoglycans (HSPGs) to properly function in this process. In developing valves, HB-EGF is synthesized in endocardial cells but accumulates in the mesenchyme by interacting with HSPGs. Disrupting the interaction between HB-EGF and HSPGs in an ex vivo model of endocardial cushion explants resulted in increased mesenchymal cell proliferation. Moreover, homozygous knock-in mice (HB(Delta)(hb/)(Delta)(hb)) expressing a mutant HB-EGF that cannot bind to HSPGs developed enlarged cardiac valves with hyperproliferation of mesenchymal cells; this resulted in a phenotype that resembled that of Hbegf-null mice. Interestingly, although Hbegf-null mice had abnormal heart chambers and lung alveoli, HB(Delta)(hb/)(Delta)(hb) mice did not exhibit these defects. These results indicate that interactions with HSPGs are essential for the function of HB-EGF, especially in cardiac valve development, in which HB-EGF suppresses mesenchymal cell proliferation.

Immunomodulatory properties of human periodontal ligament stem cells.

PubMed

Wada, Naohisa; Menicanin, Danijela; Shi, Songtao; Bartold, P Mark; Gronthos, Stan

2009-06-01

Tissue engineering utilizing periodontal ligament stem cells (PDLSCs) has recently been proposed for the development of new periodontal regenerative therapies. Although the use of autologous PDLSC transplantation eliminates the potential of a significant host immune response against the donor cells, it is often difficult to generate enough PDLSCs from one donor source due to the variation of stem cell potential between donors and disease state of each patient. In this study, we examined the immunomodulatory properties of PDLSCs as candidates for new allogeneic stem cell-based therapies. Human PDLSCs displayed cell surface marker characteristics and differentiation potential similar to bone marrow stromal stem cells (BMSSCs) and dental pulp stem cells (DPSCs). PDLSCs, BMSSCs, and DPSCs inhibited peripheral blood mononuclear cell (PBMNC) proliferation stimulated with mitogen or in an allogeneic mixed lymphocyte reaction (MLR). Interestingly, gingival fibroblasts (GFs) also suppressed allogeneic PBMNC proliferation under both assay conditions. PDLSCs, BMSSCs, DPSCs, and GFs exhibited non-cell contact dependent suppression of PBMNC proliferation in co-cultures using transwells. Furthermore, conditioned media (CM) derived from each cell type pretreated with IFN-gamma partially suppressed PBMNC proliferation when compared to CMs without IFN-gamma stimulation. In all of these mesenchymal cell types cultured with activated PBMNCs, the expression of TGF-beta1, hepatocyte growth factor (HGF) and indoleamine 2, 3-dioxygenase (IDO) was upregulated while IDO expression was upregulated following stimulation with IFN-gamma. These results suggest that PDLSCs, BMSSCs, DPSCs, and GFs possess immunosuppressive properties mediated, in part, by soluble factors, produced by activated PBMNCs. J. Cell. Physiol. 219: 667-676, 2009. (c) 2009 Wiley-Liss, Inc.

Retinal pigment epithelial cell multinucleation in the aging eye - a mechanism to repair damage and maintain homoeostasis.

PubMed

Chen, Mei; Rajapakse, Dinusha; Fraczek, Monika; Luo, Chang; Forrester, John V; Xu, Heping

2016-06-01

Retinal pigment epithelial (RPE) cells are central to retinal health and homoeostasis. Dysfunction or death of RPE cells underlies many age-related retinal degenerative disorders particularly age-related macular degeneration. During aging RPE cells decline in number, suggesting an age-dependent cell loss. RPE cells are considered to be postmitotic, and how they repair damage during aging remains poorly defined. We show that RPE cells increase in size and become multinucleate during aging in C57BL/6J mice. Multinucleation appeared not to be due to cell fusion, but to incomplete cell division, that is failure of cytokinesis. Interestingly, the phagocytic activity of multinucleate RPE cells was not different from that of mononuclear RPE cells. Furthermore, exposure of RPE cells in vitro to photoreceptor outer segment (POS), particularly oxidized POS, dose-dependently promoted multinucleation and suppressed cell proliferation. Both failure of cytokinesis and suppression of proliferation required contact with POS. Exposure to POS also induced reactive oxygen species and DNA oxidation in RPE cells. We propose that RPE cells have the potential to proliferate in vivo and to repair defects in the monolayer. We further propose that the conventionally accepted 'postmitotic' status of RPE cells is due to a modified form of contact inhibition mediated by POS and that RPE cells are released from this state when contact with POS is lost. This is seen in long-standing rhegmatogenous retinal detachment as overtly proliferating RPE cells (proliferative vitreoretinopathy) and more subtly as multinucleation during normal aging. Age-related oxidative stress may promote failure of cytokinesis and multinucleation in RPE cells. © 2016 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

A simple non-perturbing cell migration assay insensitive to proliferation effects

PubMed Central

Glenn, Honor L.; Messner, Jacob; Meldrum, Deirdre R.

2016-01-01

Migration is a fundamental cellular behavior that plays an indispensable role in development and homeostasis, but can also contribute to pathology such as cancer metastasis. Due to its relevance to many aspects of human health, the ability to accurately measure cell migration is of broad interest, and numerous approaches have been developed. One of the most commonly employed approaches, because of its simplicity and throughput, is the exclusion zone assay in which cells are allowed to migrate into an initially cell-free region. A major drawback of this assay is that it relies on simply counting cells in the exclusion zone and therefore cannot distinguish the effects of proliferation from migration. We report here a simple modification to the exclusion zone migration assay that exclusively measures cell migration and is not affected by proliferation. This approach makes use of a lineage-tracing vital stain that is retained through cell generations and effectively reads out migration relative to the original, parental cell population. This modification is simple, robust, non-perturbing, and inexpensive. We validate the method in a panel of cell lines under conditions that inhibit or promote migration and demonstrate its use in normal and cancer cell lines as well as primary cells. PMID:27535324

A Benzothiazole Derivative (5g) Induces DNA Damage And Potent G2/M Arrest In Cancer Cells.

PubMed

Hegde, Mahesh; Vartak, Supriya V; Kavitha, Chandagirikoppal V; Ananda, Hanumappa; Prasanna, Doddakunche S; Gopalakrishnan, Vidya; Choudhary, Bibha; Rangappa, Kanchugarakoppal S; Raghavan, Sathees C

2017-05-31

Chemically synthesized small molecules play important role in anticancer therapy. Several chemical compounds have been reported to damage the DNA, either directly or indirectly slowing down the cancer cell progression by causing a cell cycle arrest. Direct or indirect reactive oxygen species formation causes DNA damage leading to cell cycle arrest and subsequent cell death. Therefore, identification of chemically synthesized compounds with anticancer potential is important. Here we investigate the effect of benzothiazole derivative (5g) for its ability to inhibit cell proliferation in different cancer models. Interestingly, 5g interfered with cell proliferation in both, cell lines and tumor cells leading to significant G2/M arrest. 5g treatment resulted in elevated levels of ROS and subsequently, DNA double-strand breaks (DSBs) explaining observed G2/M arrest. Consistently, we observed deregulation of many cell cycle associated proteins such as CDK1, BCL2 and their phosphorylated form, CyclinB1, CDC25c etc. Besides, 5g treatment led to decreased levels of mitochondrial membrane potential and activation of apoptosis. Interestingly, 5g administration inhibited tumor growth in mice without significant side effects. Thus, our study identifies 5g as a potent biochemical inhibitor to induce G2/M phase arrest of the cell cycle, and demonstrates its anticancer properties both ex vivo and in vivo.

p205, a potential tumor suppressor, inhibits cell proliferation via multiple pathways of cell cycle regulation.

PubMed

Asefa, Benyam; Dermott, Jonathan M; Kaldis, Philipp; Stefanisko, Karen; Garfinkel, David J; Keller, Jonathan R

2006-02-20

p205 is a member of the interferon-inducible p200 family of proteins that regulate cell proliferation. Over-expression of p205 inhibits cell growth, although its mechanism of action is currently unknown. Therefore, we evaluated the effect of p205 on the p53 and Rb-dependent pathways of cell cycle regulation. p205 expression results in elevated levels of p21, and activates the p21 promoter in vitro in a p53-dependent manner. In addition, p205 induces increased expression of Rb, and binds directly to Rb and p53. Interestingly, p205 also induces growth inhibition independent of p53 and Rb by delaying G2/M progression in proliferating cells, and is a substrate for Cdk2 kinase activity. Finally, we have identified other binding partners of p205 by a yeast two-hybrid screen, including the paired homeodomain protein HoxB2. Taken together, our results indicate that p205 induces growth arrest by interaction with multiple transcription factors that regulate the cell cycle, including but not entirely dependent on the Rb- and p53-mediated pathways of growth inhibition.

Molecular Pathways: Is AMPK a Friend or a Foe in Cancer?

PubMed Central

Hardie, D. Grahame

2015-01-01

The AMP-activated protein kinase (AMPK) is a sensor of cellular energy status expressed in essentially all eukaryotic cells. Once activated by energetic stress via a mechanism that detects increases in AMP:ATP and ADP:ATP ratios, AMPK acts to restore energy homeostasis by switching on catabolic pathways that generate ATP, while switching off ATP-consuming processes, including anabolic pathways required for cell growth and proliferation. AMPK activation promotes the glucose-sparing, oxidative metabolism utilized by most quiescent cells, rather than the rapid glucose uptake and glycolysis used by most proliferating cells. Numerous pharmacological activators of AMPK are known, including drugs in long use such as salicylate and metformin, and there is evidence that regular use of either of the latter provides protection against development of cancer. Tumor cells appear to be under selection pressure to down-regulate AMPK, thus limiting its restraining influence on cell growth and proliferation, and several interesting mechanisms by which this occurs are discussed. Paradoxically, however, a complete loss of AMPK function, which appears to be rare in human cancers, may be deleterious to survival of tumor cells. AMPK can therefore either be a friend and a foe in cancer, depending on the context. PMID:26152739

Synthetic RORγt Agonists Enhance Protective Immunity

PubMed Central

Chang, Mi Ra; Dharmarajan, Venkatasubramanian; Doebelin, Christelle; Garcia-Ordonez, Ruben D.; Novick, Scott J.; Kuruvilla, Dana S.; Kamenecka, Theodore M.; Griffin, Patrick R.

2016-01-01

The T cell specific RORγ isoform RORγt has been shown to be the key lineage-defining transcription factor to initiate the differentiation program of TH17 and Tc17 cells, cells that have demonstrated anti-tumor efficacy. RORγt controls gene networks that enhance immunity including increased IL17 production and decreased immune suppression. Both synthetic and putative endogenous agonists of RORγt have been shown to increase the basal activity of RORγt enhancing TH17 cell proliferation. Here we show that activation of RORγt using synthetic agonists drives proliferation of TH17 cells while decreasing levels of the immune checkpoint protein PD-1, a mechanism that should enhance anti-tumor immunity while blunting tumor associated adaptive immune resistance. Interestingly, putative endogenous agonists drive proliferation of TH17 cells but do not repress PD-1. These findings suggest that synthetic agonists of RORγt should activate TC17/TH17 cells (with concomitant reduction in the Tregs population), repress PD-1, and produce IL17 in situ (a factor associated with good prognosis in cancer). Enhanced immunity and blockage of immune checkpoints has transformed cancer treatment, thus such a molecule would provide a unique approach for the treatment of cancer. PMID:26785144

Melanoma exosomes deliver a complex biological payload that upregulates PTPN11 to suppress T lymphocyte function.

PubMed

Wu, Yueting; Deng, Wentao; McGinley, Emily Chambers; Klinke, David J

2017-03-01

As exosomes are emerging as a new mode of intercellular communication, we hypothesized that the payload contained within exosomes is shaped by somatic evolution. To test this, we assayed the impact on primary CD8+ T-cell function, a key mechanism for antitumor immunity, of exosomes derived from three melanoma-related cell lines. While morphologically similar, exosomes from each cell line were functionally different, as B16F0 exosomes dose-dependently suppressed T-cell proliferation. In contrast, Cloudman S91 exosomes promoted T-cell proliferation and Melan-A exosomes had a negligible effect on primary CD8+ T cells. Mechanistically, transcript profiling suggested that exosomal mRNA is enriched for full-length mRNAs that target immune-related pathways. Interestingly, B16F0 exosomes were unique in that they contained both protein and mRNA for PTPN11, which inhibited T-cell proliferation. Collectively, the results suggest that upregulation of PTPN11 by B16F0 exosomes to tumor infiltrating lymphocytes would bypass the extracellular control of the immune checkpoints. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Effects of real or simulated microgravity on plant cell growth and proliferation

NASA Astrophysics Data System (ADS)

Medina, Francisco Javier; Manzano, Ana Isabel; Herranz, Raul; Dijkstra, Camelia; Larkin, Oliver; Hill, Richard; Carnero-Díaz, Eugénie; van Loon, Jack J. W. A.; Anthony, Paul; Davey, Michael R.; Eaves, Laurence

Experiments on seed germination and seedling growth performed in real microgravity on the International Space Station and in different facilities for simulating microgravity in Earth-based laboratories (Random Positioning Machine and Magnetic Levitation), have provided evidence that the absence of gravity (or the artificial compensation of the gravity vector) results in the uncoupling of cell growth and proliferation in root meristematic cells. These are two essential cellular functions that support plant growth and development, which are strictly coordinated under normal ground gravity conditions. Under conditions of altered gravity, we observe that cell proliferation is enhanced, whereas cell growth is reduced, according to different morphometric, cytological and immunocytochemical parameters. Since coordination of cell growth and proliferation are major features of meristematic cells, this observed uncoupling represents a major stress condition for these cells, inducing major alterations in the pattern of plant development. Moreover, the expression of the cyclin B1 gene, a regulator of the entry into mitosis and normally used as an indicator of cell proliferation, appears reduced in the smaller and more actively proliferating cells of samples grown under the conditions of our experiments. These results are compatible with an alteration of the regulation of the cell cycle, producing a shorter G2 period. Interestingly, while cyclin B1 expression is depleted in these conditions in root meristematic cells, it is enhanced in cotyledons of the same seedlings, as shown by qPCR and by the expression of the gus reporter gene. It is known that regulation of root growth (including regulation of root meristematic activity) is driven mainly by auxin, whereas cytokinin is the key hormone regulating cotyledon growth. Therefore, our results indicate a major role of auxin in the sensitivity to altered gravity of root meristematic cells. Auxin is crucial in maintaining the coupling of cell growth and proliferation under normal conditions and it should have a decisive influence in the uncoupling of these processes under altered gravity. Experiments to detect auxin distribution in roots under altered gravity produced by diamagnetic levitation have shown that the lateral balanced distribution of the growth regulator in the root cap is altered slightly and that the total concentration of the auxin detected in root tips is somewhat reduced. These effects are independent of the orientation of statoliths in columella cells.

Species-specific differences in peroxisome proliferation, catalase, and SOD2 upregulation as well as toxicity in human, mouse, and rat hepatoma cells induced by the explosive and environmental pollutant 2,4,6-trinitrotoluene.

PubMed

Naumenko, Ekaterina Anatolevna; Ahlemeyer, Barbara; Baumgart-Vogt, Eveline

2017-03-01

2,4,6-Trinitrotoluene (TNT) has been widely used as an explosive substance and its toxicity is still of interest as it persisted in polluted areas. TNT is metabolized in hepatocytes which are prone to its toxicity. Since analysis of the human liver or hepatocytes is restricted due to ethical reasons, we investigated the effects of TNT on cell viability, reactive oxygen species (ROS) production, peroxisome proliferation, and antioxidative enzymes in human (HepG2), mouse (Hepa 1-6), and rat (H4IIEC3) hepatoma cell lines. Under control conditions, hepatoma cells of all three species were highly comparable exhibiting identical proliferation rates and distribution of their cell cycle phases. However, we found strong differences in TNT toxicity with the lowest IC 50 values (highest cell death rate) for rat cells, whereas human and mouse cells were three to sevenfold less sensitive. Moreover, a strong decrease in cellular dehydrogenase activity (MTT assay) and increased ROS levels were noted. TNT caused peroxisome proliferation with rat hepatoma cells being most responsive followed by those from mouse and human. Under control conditions, rat cells contained fivefold higher peroxisomal catalase and mitochondrial SOD2 activities and a twofold higher capacity to reduce MTT than human and mouse cells. TNT treatment caused an increase in catalase and SOD2 mRNA and protein levels in human and mouse, but not in rat cells. Similarly, human and mouse cells upregulated SOD2 activity, whereas rat cells failed therein. We conclude that TNT induced oxidative stress, peroxisome proliferation and mitochondrial damage which are highest in rat cells rendering them most susceptible toward TNT. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 989-1006, 2017. © 2016 Wiley Periodicals, Inc.

Age-specific functional epigenetic changes in p21 and p16 in injury-activated satellite cells

PubMed Central

Li, Ju; Han, Suhyoun; Cousin, Wendy; Conboy, Irina M.

2014-01-01

The regenerative capacity of muscle dramatically decreases with age because old muscle stem cells fail to proliferate in response to tissue damage. Here we uncover key age-specific differences underlying this proliferative decline: namely, the genetic loci of CDK inhibitors (CDKI) p21 and p16 are more epigenetically silenced in young muscle stem cells, as compared to old, both in quiescent cells and those responding to tissue injury. Interestingly, phosphorylated ERK (pERK) induced in these cells by ectopic FGF-2 is found in association with p21 and p16 promoters, and moreover, only in the old cells. Importantly, in the old satellite cells FGF-2/pERK silences p21 epigenetically and transcriptionally, which leads to reduced p21 protein levels and enhanced cell proliferation. In agreement with the epigenetic silencing of the loci, young muscle stem cells do not depend as much as old on ectopic FGF/pERK for their myogenic proliferation. In addition, other CDKIs, such asp15INK4B and p27KIP1, become elevated in satellite cells with age, confirming and explaining the profound regenerative defect of old muscle. This work enhances our understanding of tissue aging, promoting strategies for combating age-imposed tissue degeneration. PMID:25447026

Stearoyl CoA Desaturase (SCD) Facilitates Proliferation of Prostate Cancer Cells through Enhancement of Androgen Receptor Transactivation

PubMed Central

Kim, Seung-Jin; Choi, Hojung; Park, Sung-Soo; Chang, Chawnshang; Kim, Eungseok

2011-01-01

Stearoyl-CoA desaturase (SCD), the rate-limiting enzyme in the biosynthesis of monounsaturated fatty acids, is highly expressed in prostate cancer although the SCD protein has been known to be rapidly turned over by proteolytic cleavage. The present data demonstrate that SCD can promote proliferation of androgen receptor (AR)-positive LNCaP prostate cancer cells and enhance dihydrotestosterone (DHT)-induced AR transcriptional activity, resulting in increased expression of prostatespecific antigen (PSA) and kallikrein-related peptidase 2 (KLK2). Interestingly, among the previously reported SCDderived peptides produced by proteolytic cleavage of SCD, a peptide spanning amino acids 130-162 of SCD (SCDCoRNR) contained the CoRNR box motif (LFLII) and enhanced AR transcriptional activity. In contrast, a mutant SCD-CoRNR in which Leu136 was replaced by Ala had no effect on AR transcriptional activity. Moreover, SCDCoRNR directly interacted with AR and inhibited RIP140 suppression of AR transactivation. Knockdown of the SCD gene by SCD microRNA suppressed AR transactivation with decreased cell proliferation, suggesting that SCD may regulate the proliferation of LNCaP cells via modulation of AR transcriptional activity. Moreover, ectopic expression of SCD in LNCaP cells facilitated LNCaP tumor formation and growth in nude mice. Together, the data indicate that SCD plays a key role in the regulation of AR transcriptional activity in prostate cancer cells. PMID:21331774

G protein-coupled receptor 30 is critical for a progestin-induced growth inhibition in MCF-7 breast cancer cells.

PubMed

Ahola, Tytti M; Manninen, Tommi; Alkio, Niina; Ylikomi, Timo

2002-09-01

The issue of how progesterone affects mammary gland growth is controversial, and the mechanism governing the effects of the hormone remains mostly unknown. We have previously shown that G protein-coupled receptor 30 (GPR30) is a progestin target gene whose expression correlates with progestin-induced growth inhibition in breast cancer cells. In this study, we investigate the role of GPR30 in regulating cell proliferation and mediating progestin-induced growth inhibition. When progestin failed to inhibit the growth of MCF-7 cells and instead stimulated growth, GPR30 was down-regulated. In this way, the inhibitory or stimulatory affects that progestin has on proliferation correlated with the level of expression of GPR30. Transient expression of GPR30 resulted in a marked inhibition of cell proliferation independent of estrogen treatment. GPR30 antisense was used to evaluate the role of GPR30 expression in progestin-induced growth inhibition. A diminished GPR30 mRNA expression by the antisense stimulated growth. Interestingly, GPR30 antisense abrogated the growth inhibitory effect of progestin and progesterone. Indeed, progestin induced 1) a reduction in cell proliferation, 2) G1-phase arrest, and 3) down-regulation of cyclin D1 was diminished. These data suggest that the orphan receptor, GPR30, is important for the inhibitory effect of progestin on growth.

9-Cis-Retinoic Acid Induces Growth Inhibition in Retinoid-Sensitive Breast Cancer and Sea Urchin Embryonic Cells via Retinoid X Receptor α and Replication Factor C3

PubMed Central

Maeng, Sejung; Kim, Gil Jung; Choi, Eun Ju; Yang, Hyun Ok; Lee, Dong-Sup

2012-01-01

There is widespread interest in defining factors and mechanisms that suppress the proliferation of cancer cells. Retinoic acid (RA) is a potent suppressor of mammary cancer and developmental embryonic cell proliferation. However, the molecular mechanisms by which 9-cis-RA signaling induces growth inhibition in RA-sensitive breast cancer and embryonic cells are not apparent. Here, we provide evidence that the inhibitory effect of 9-cis-RA on cell proliferation depends on 9-cis-RA-dependent interaction of retinoid X receptor α (RXRα) with replication factor C3 (RFC3), which is a subunit of the RFC heteropentamer that opens and closes the circular proliferating cell nuclear antigen (PCNA) clamp on DNA. An RFC3 ortholog in a sea urchin cDNA library was isolated by using the ligand-binding domain of RXRα as bait in a yeast two-hybrid screening. The interaction of RFC3 with RXRα depends on 9-cis-RA and bexarotene, but not on all-trans-RA or an RA receptor (RAR)-selective ligand. Truncation and mutagenesis experiments demonstrated that the C-terminal LXXLL motifs in both human and sea urchin RFC3 are critical for the interaction with RXRα. The transient interaction between 9-cis-RA-activated RXRα and RFC3 resulted in reconfiguration of the PCNA-RFC complex. Furthermore, we found that knockdown of RXRα or overexpression of RFC3 impairs the ability of 9-cis-RA to inhibit proliferation of MCF-7 breast cancer cells and sea urchin embryogenesis. Our results indicate that 9-cis-RA-activated RXRα suppresses the growth of RA-sensitive breast cancer and embryonic cells through RFC3. PMID:22949521

Cancer-associated fibroblasts promote endometrial cancer growth via activation of interleukin-6/STAT-3/c-Myc pathway.

PubMed

Subramaniam, Kavita S; Omar, Intan Sofia; Kwong, Soke Chee; Mohamed, Zahurin; Woo, Yin Ling; Mat Adenan, Noor Azmi; Chung, Ivy

2016-01-01

Cancer-associated fibroblasts (CAFs) secrete various pro-tumorigenic cytokines, yet the role of these cytokines in the progression of endometrial cancer remains unclear. We found that CAFs isolated from human endometrial cancer (EC) tissues secreted high levels of interleukin-6 (IL-6), which promotes EC cell proliferation in vitro. Neutralizing IL-6 in CAF-conditioned media reduced (47% inhibition) while IL-6 recombinant protein increased cell proliferation (~2.4 fold) of both EC cell lines and primary cultures. IL-6 receptors (IL-6R and gp130) were expressed only in EC epithelial cells but not in CAF, indicating a one-way paracrine signaling. In the presence of CAF-conditioned media, Janus kinase/signal transducers and activators of transcription (JAK/STAT3) pathway was activated in EC cells. Treatment with JAK and STAT3 specific inhibitors, AD412 and STATTIC, respectively, significantly abrogated CAF-mediated cell proliferation, indicating the role of IL-6 activation in EC cell proliferation. We further showed that one of STAT-3 target genes, c-Myc, was highly induced in EC cells after exposure to CAF-conditioned medium at both mRNA (>105-fold vs. control) and protein level (>2-fold vs. control). EC cell proliferation was dependent on c-Myc expression, as RNAi-mediated c-Myc down-regulation led to a significant 46% reduction in cell viability when compared with scrambled control. Interestingly, CAF-conditioned media failed to promote proliferation in EC cells with reduced c-Myc expression, suggesting that CAF-mediated cell proliferation was also dependent on c-Myc expression. Subcutaneous tumor xenograft model showed that EC cells grew at least 1.4 times larger when co-injected with CAF, when compared to those injected with EC cells alone. Mice injected with EC cells with down-regulated c-Myc expression, however, showed at least 2.5 times smaller tumor compared to those in control group. Notably, there was no increase of tumor size when co-injected with CAFs. Further immunohistochemical staining on human tissues showed positive expression of IL-6 receptors, phosphorylated-STAT3 and c-Myc in human EC tissues with less signals in benign endometrium. Taken together, our data suggests that IL-6 secreted by CAF induces c-Myc expression to promote EC proliferation in vitro and in vivo. IL-6 pathway can be a potential target to disrupt tumor-stroma interaction in endometrial cancer progression.

Erbin loss promotes cancer cell proliferation through feedback activation of Akt-Skp2-p27 signaling

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

Huang, Hao; Laboratory of Cellular and Molecular Immunology, Medical School of Henan University, Kaifeng 475004; Song, Yuhua

2015-07-31

Erbin localizes at the basolateral membrane to regulate cell junctions and polarity in epithelial cells. Dysregulation of Erbin has been implicated in tumorigenesis, and yet it is still unclear if and how disrupted Erbin regulates the biological behavior of cancer cells. We report here that depletion of Erbin leads to cancer cell excessive proliferation in vitro and in vivo. Erbin deficiency accelerates S-phase entry by down-regulating CDK inhibitors p21 and p27 via two independent mechanisms. Mechanistically, Erbin loss promotes p27 degradation by enhancing E3 ligase Skp2 activity though augmenting Akt signaling. Interestingly, we also show that Erbin is an unstable protein whenmore » the Akt-Skp2 signaling is aberrantly activated, which can be specifically destructed by SCF-Skp2 ligase. Erbin loss facilitates cell proliferation and migration in Skp2-dependent manner. Thus, our finding illustrates a novel negative feedback loop between Erbin and Akt-Skp2 signaling. It suggests disrupted Erbin links polarity loss, hyperproliferation and tumorigenesis. - Highlights: • Erbin loss leads to cancer cell excessive proliferation in vitro and in vivo. • Erbin loss accelerates cell cycle though down-regulating p21 and p27 expression. • Erbin is a novel negative modulator of Akt1-Skp2-p27 signaling pathway. • Our study suggests that Erbin loss contributes to Skp2 oncogenic function.« less

Endogenous GFAP-Positive Neural Stem/Progenitor Cells in the Postnatal Mouse Cortex Are Activated following Traumatic Brain Injury

PubMed Central

Ahmed, Aminul I.; Shtaya, Anan B.; Zaben, Malik J.; Owens, Emma V.; Kiecker, Clemens

2012-01-01

Abstract Interest in promoting regeneration of the injured nervous system has recently turned toward the use of endogenous stem cells. Elucidating cues involved in driving these precursor cells out of quiescence following injury, and the signals that drive them toward neuronal and glial lineages, will help to harness these cells for repair. Using a biomechanically validated in vitro organotypic stretch injury model, cortico-hippocampal slices from postnatal mice were cultured and a stretch injury equivalent to a severe traumatic brain injury (TBI) applied. In uninjured cortex, proliferative potential under in vitro conditions is virtually absent in older slices (equivalent postnatal day 15 compared to 8). However, following a severe stretch injury, this potential is restored in injured outer cortex. Using slices from mice expressing a fluorescent reporter on the human glial fibrillary acidic protein (GFAP) promoter, we show that GFAP+ cells account for the majority of proliferating neurospheres formed, and that these cells are likely to arise from the cortical parenchyma and not from the subventricular zone. Moreover, we provide evidence for a correlation between upregulation of sonic hedgehog signaling, a pathway known to regulate stem cell proliferation, and this restoration of regenerative potential following TBI. Our results indicate that a source of quiescent endogenous stem cells residing in the cortex and subcortical tissue proliferate in vitro following TBI. Moreover, these proliferating cells are multipotent and are derived mostly from GFAP-expressing cells. This raises the possibility of using this endogenous source of stem cells for repair following TBI. PMID:21895532

Hyper-O-GlcNAcylation of YB-1 affects Ser102 phosphorylation and promotes cell proliferation in hepatocellular carcinoma

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

Liu, Qingqing; Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Nantong University, 19 Qi-xiu Road, Nantong 226001, Jiangsu Province; Tao, Tao

As an essential post-translational modification, O-GlcNAcylation has been thought to be able to modulate various nuclear and cytoplasmic proteins and is emerging as a key regulator of multiple biological processes, such as transcription, cell growth, signal transduction, and cell motility. Recently, authoritative glycomics analyses have reported extensive crosstalk between O-GlcNAcylation and phosphorylation, which always dynamically interplay with each other and regulate signaling, transcription, and other cellular processes. Also, plentiful studies have shown close correlation between YB-1 phosphorylation and tumorigenesis. Therefore, our study aimed to determine whether YB-1 was O-GlcNAc modified and whether such modification could interact with its phosphorylation duringmore » the process of HCC development. Western blot and immunohistochemistry were firstly conducted to reveal obvious up-regulation of YB-1, OGT and O-GlcNAc modification in HCC tissues. What is more, not only YB-1 was identified to be O-GlcNAcylated but hyper-O-GlcNAcylation was demonstrated to facilitate HCC cell proliferation in a YB-1 dependent manner. Moreover, we detected four specific O-GlcNAc sites and confirmed T126A to be the most effective mutant in HCC cell proliferation via close O-GlcNAcylation-phosphorylation interaction. Even more interestingly, we discovered that T126A-induced HCC cell retardation and subdued transcriptional activity of YB-1 could be partially reversed by T126A/S102E mutant. From all above, it is not difficult to find that glycosylated-YB-1 mainly enhanced cell proliferation through congenerous actions with YB-1 phosphorylation and thus played indispensable roles in fine-tuning cell proliferation and procession of HCC. - Highlights: • YB-1 and OGT are associated with HCC prognosis. • YB-1 is O-GlcNAc modified in HCC. • Hyper-O-GlcNAcylation promotes HCC cell proliferation in dependent of YB-1. • The proliferating role of O-GlcNAcylation is based on Ser102 phosphorylation of YB-1.« less

p75 neurotrophin receptor cleavage by α- and γ-secretases is required for neurotrophin-mediated proliferation of brain tumor-initiating cells.

PubMed

Forsyth, Peter A; Krishna, Niveditha; Lawn, Samuel; Valadez, J Gerardo; Qu, Xiaotao; Fenstermacher, David A; Fournier, Michelle; Potthast, Lisa; Chinnaiyan, Prakash; Gibney, Geoffrey T; Zeinieh, Michele; Barker, Philip A; Carter, Bruce D; Cooper, Michael K; Kenchappa, Rajappa S

2014-03-21

Malignant gliomas are highly invasive, proliferative, and resistant to treatment. Previously, we have shown that p75 neurotrophin receptor (p75NTR) is a novel mediator of invasion of human glioma cells. However, the role of p75NTR in glioma proliferation is unknown. Here we used brain tumor-initiating cells (BTICs) and show that BTICs express neurotrophin receptors (p75NTR, TrkA, TrkB, and TrkC) and their ligands (NGF, brain-derived neurotrophic factor, and neurotrophin 3) and secrete NGF. Down-regulation of p75NTR significantly decreased proliferation of BTICs. Conversely, exogenouous NGF stimulated BTIC proliferation through α- and γ-secretase-mediated p75NTR cleavage and release of its intracellular domain (ICD). In contrast, overexpression of the p75NTR ICD induced proliferation. Interestingly, inhibition of Trk signaling blocked NGF-stimulated BTIC proliferation and p75NTR cleavage, indicating a role of Trk in p75NTR signaling. Further, blocking p75NTR cleavage attenuated Akt activation in BTICs, suggesting role of Akt in p75NTR-mediated proliferation. We also found that p75NTR, α-secretases, and the four subunits of the γ-secretase enzyme were elevated in glioblastoma multiformes patients. Importantly, the ICD of p75NTR was commonly found in malignant glioma patient specimens, suggesting that the receptor is activated and cleaved in patient tumors. These results suggest that p75NTR proteolysis is required for BTIC proliferation and is a novel potential clinical target.

p75 Neurotrophin Receptor Cleavage by α- and γ-Secretases Is Required for Neurotrophin-mediated Proliferation of Brain Tumor-initiating Cells*

PubMed Central

Forsyth, Peter A.; Krishna, Niveditha; Lawn, Samuel; Valadez, J. Gerardo; Qu, Xiaotao; Fenstermacher, David A.; Fournier, Michelle; Potthast, Lisa; Chinnaiyan, Prakash; Gibney, Geoffrey T.; Zeinieh, Michele; Barker, Philip A.; Carter, Bruce D.; Cooper, Michael K.; Kenchappa, Rajappa S.

2014-01-01

Malignant gliomas are highly invasive, proliferative, and resistant to treatment. Previously, we have shown that p75 neurotrophin receptor (p75NTR) is a novel mediator of invasion of human glioma cells. However, the role of p75NTR in glioma proliferation is unknown. Here we used brain tumor-initiating cells (BTICs) and show that BTICs express neurotrophin receptors (p75NTR, TrkA, TrkB, and TrkC) and their ligands (NGF, brain-derived neurotrophic factor, and neurotrophin 3) and secrete NGF. Down-regulation of p75NTR significantly decreased proliferation of BTICs. Conversely, exogenouous NGF stimulated BTIC proliferation through α- and γ-secretase-mediated p75NTR cleavage and release of its intracellular domain (ICD). In contrast, overexpression of the p75NTR ICD induced proliferation. Interestingly, inhibition of Trk signaling blocked NGF-stimulated BTIC proliferation and p75NTR cleavage, indicating a role of Trk in p75NTR signaling. Further, blocking p75NTR cleavage attenuated Akt activation in BTICs, suggesting role of Akt in p75NTR-mediated proliferation. We also found that p75NTR, α-secretases, and the four subunits of the γ-secretase enzyme were elevated in glioblastoma multiformes patients. Importantly, the ICD of p75NTR was commonly found in malignant glioma patient specimens, suggesting that the receptor is activated and cleaved in patient tumors. These results suggest that p75NTR proteolysis is required for BTIC proliferation and is a novel potential clinical target. PMID:24519935

Essential components for ex vivo proliferation of mesenchymal stromal cells.

PubMed

Fekete, Natalie; Rojewski, Markus Thomas; Lotfi, Ramin; Schrezenmeier, Hubert

2014-02-01

Mesenchymal stromal cells (MSCs) are highly interesting candidates for clinical applications in regenerative medicine. Due to their low occurrence in human tissues, extensive in vitro expansion is necessary to obtain sufficient cell numbers applicable as a clinical dose in the context of cellular therapy. Current cell culture media formulations for the isolation and expansion of MSCs include fetal calf serum (FCS), human AB serum (ABS), or human platelet lysate (PL) as a supplement. However, these established supplements are inherently ill-defined formulations that contain a variety of bioactive molecules in varying batch-to-batch compositions and the risk of transmitting pathogens that escape routine screening procedures. In this study, we have comparatively characterized the capacity of commonly used basal media, such as the Minimum Essential Medium alpha (αMEM), Dulbecco's modified Eagle's medium (DMEM), Iscove's Modified Dulbecco's Medium (IMDM), and RPMI 1640 as well as human- and animal-derived supplements, that is, PL, ABS, and FCS to stimulate cell proliferation. MSC proliferation was observed to be optimal in the PL-supplemented αMEM. Using a combinatorial approach, we then assessed a library of soluble factors, including mitogens (TGF-β1, Activin A, bFGF, EGF, IGF-I, PDGF-BB, and VEGF), chemokines (CCL21, CCL25, CXCL12, and RANTES), proteins (human serum albumin), lipids (e.g., oleic acid, linoleic acid, and arachidonic acid), and hormones (dexamethasone, insulin, and TSH), to create a defined medium as well as coating of cell culture surfaces to promote robust MSC proliferation in vitro. A combination of recombinant human factors partially met the nutritional requirements of bone marrow-derived MSCs, and was able to promote cell proliferation comparable to about 5% PL if supplemented with auxiliary 0.6%-1.2% PL. Maximal MSC proliferation was achieved by combining 5% PL with a cocktail of recombinant factors and did not depend on coating of cell culture surfaces.

Clonal analysis of human embryonic stem cell differentiation into teratomas.

PubMed

Blum, Barak; Benvenisty, Nissim

2007-08-01

Differentiation of human embryonic stem cells (HESCs) can be studied in vivo through the induction of teratomas in immune-deficient mice. Cells within the teratomas differentiate into all three embryonic germ layers. However, the exact nature of the proliferation and differentiation of HESCs within the teratoma is not fully characterized, and it is not clear whether the differentiation is cell autonomous or affected by neighboring cells. Here, we establish a genetic approach to study the clonality of differentiation in teratomas using a mixture of HESC lines. We first demonstrate, by means of 5-bromo-2'-deoxyuridine incorporation, that cell proliferation occurs throughout the teratoma, and that there are no clusters of undifferentiated-proliferating cells. Using a combination of laser capture microdissection and DNA fingerprinting analysis, we show that different cell lines contribute mutually to the same distinctive tissue structures. Further support for the nonclonal differentiation within the teratoma was achieved by fluorescence in situ hybridization analysis of sex chromosomes. We therefore suggest that in vivo differentiation of HESCs is polyclonal and, thus, may not be cell autonomous, stressing the need for a three-dimensional growth in order to achieve complex differentiation of HESCs. Disclosure of potential conflicts of interest is found at the end of this article.

Comparative analysis of the immunomodulatory capacities of human bone marrow- and adipose tissue-derived mesenchymal stromal cells from the same donor.

PubMed

Valencia, Jaris; Blanco, Belén; Yáñez, Rosa; Vázquez, Miriam; Herrero Sánchez, Carmen; Fernández-García, María; Rodríguez Serrano, Concepción; Pescador, David; Blanco, Juan F; Hernando-Rodríguez, Miriam; Sánchez-Guijo, Fermín; Lamana, María Luisa; Segovia, José Carlos; Vicente, Ángeles; Del Cañizo, Consuelo; Zapata, Agustín G

2016-10-01

The immunomodulatory properties of mesenchymal stromal cells (MSCs), together with their tissue regenerative potential, make them interesting candidates for clinical application. In the current study, we analyzed the in vitro immunomodulatory effects of MSCs derived from bone marrow (BM-MSCs) and from adipose tissue (AT-MSCs) obtained from the same donor on both innate and acquired immunity cells. BM-MSCs and AT-MSCs were expanded to fourth or fifth passage and co-cultured with T cells, monocytes or natural killer (NK) cells isolated from human peripheral blood and stimulated in vitro. The possible differing impact of MSCs obtained from distinct sources on phenotype, cell proliferation and differentiation, cytokine production and function of these immune cells was comparatively analyzed. BM-MSCs and AT-MSCs induced a similar decrease in NK-cell proliferation, cytokine secretion and expression of both activating receptors and cytotoxic molecules. However, only BM-MSCs significantly reduced NK-cell cytotoxic activity, although both MSC populations showed the same susceptibility to NK-cell-mediated lysis. AT-MSCs were more potent in inhibiting dendritic-cell (DC) differentiation than BM-MSC, but both MSC populations similarly reduced the ability of DCs to induce CD4(+) T-cell proliferation and cytokine production. BM-MSCs and AT-MSCs induced a similar decrease in T-cell proliferation and production of inflammatory cytokines after activation. AT-MSCs and BM-MSCs from the same donor had similar immunomodulatory capacity on both innate and acquired immunity cells. Thus, other variables, such as accessibility of samples or the frequency of MSCs in the tissue should be considered to select the source of MSC for cell therapy. Copyright © 2016 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

In vitro testing of Nd:YAG laser processed calcium phosphate coatings.

PubMed

De Carlos, A; Lusquiños, F; Pou, J; León, B; Pérez-Amor, M; Driessens, F C M; Hing, K; Best, S; Bonfield, W

2006-11-01

Nd:YAG laser cladding is a new method for deposition of a calcium phosphate onto metallic surfaces of interest in implantology. The aim of this study was to compare the biologic response of MG-63 human osteoblast-like cells grown on Ti-6Al-4V substrates coated with a calcium phosphate layer applied using different methods: plasma spraying as reference material and Nd:YAG laser cladding as test material. Tissue culture polystyrene was used as negative control. The Nd:YAG laser clad material showed a behaviour similar to the reference material, plasma spray, respective to cell morphology (SEM observations), cell proliferation (AlamarBlue assay) and cytotoxicity of extracts (MTT assay). Proliferation, as measured by the AlamarBlue assay, showed little difference in the metabolic activity of the cells on the materials over an 18 day culture period. There were no significant differences in the cellular growth response on the test material when compared to the ones exhibited by the reference material. In the solvent extraction test all the extracts had some detrimental effect on cellular activity at 100% concentration, although cells incubated in the test material extract showed a proliferation rate similar to that of the reference material. To better understand the scope of these results it should be taken into account that the Nd:YAG clad coating has recently been developed. The fact that its in vitro performance is comparable to that produced by plasma spray, a material commercially available for more than ten years, indicates that this new laser based method could be of commercial interest in the near future.

Adipose-derived stromal cells inhibit prostate cancer cell proliferation inducing apoptosis

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

Takahara, Kiyoshi; Ii, Masaaki, E-mail: masaii@art.osaka-med.ac.jp; Inamoto, Teruo

2014-04-18

Highlights: • AdSC transplantation exhibits inhibitory effect on tumor progressions of PCa cells. • AdSC-induced PCa cell apoptosis may occur via the TGF-β signaling pathway. • High expression of the TGF-β1 gene in AdSCs. - Abstract: Mesenchymal stem cells (MSCs) have generated a great deal of interest in the field of regenerative medicine. Adipose-derived stromal cells (AdSCs) are known to exhibit extensive proliferation potential and can undergo multilineage differentiation, sharing similar characteristics to bone marrow-derived MSCs. However, as the effect of AdSCs on tumor growth has not been studied sufficiently, we assessed the degree to which AdSCs affect the proliferationmore » of prostate cancer (PCa) cell. Human AdSCs exerted an inhibitory effect on the proliferation of androgen-responsive (LNCaP) and androgen-nonresponsive (PC3) human PCa cells, while normal human dermal fibroblasts (NHDFs) did not, and in fact promoted PCa cell proliferation to a degree. Moreover, AdSCs induced apoptosis of LNCaP cells and PC3 cells, activating the caspase3/7 signaling pathway. cDNA microarray analysis suggested that AdSC-induced apoptosis in both LNCaP and PC3 cells was related to the TGF-β signaling pathway. Consistent with our in vitro observations, local transplantation of AdSCs delayed the growth of tumors derived from both LNCaP- and PC3-xenografts in immunodeficient mice. This is the first preclinical study to have directly demonstrated that AdSC-induced PCa cell apoptosis may occur via the TGF-β signaling pathway, irrespective of androgen-responsiveness. Since autologous AdSCs can be easily isolated from adipose tissue without any ethical concerns, we suggest that therapy with these cells could be a novel approach for patients with PCa.« less

Biological responses of T cells encapsulated with polyelectrolyte-coated gold nanorods and their cellular activities in a co-culture system

NASA Astrophysics Data System (ADS)

Wattanakull, Porntida; Killingsworth, Murray C.; Pissuwan, Dakrong

2017-11-01

Currently, human T cell therapy is of considerable scientific interest. In addition, cell encapsulation has become an attractive approach in biomedical applications. Here, we propose an innovative technique of single-cell encapsulation of human T cells using polyelectrolytes combined with gold nanorods. We have demonstrated encapsulation of human Jurkat T cells with poly(sodium 4-styrenesulfonate) (PSS)-coated gold nanorods (PSS-GNRs). Other forms of encapsulation, using polyelectrolytes without GNRs, were also performed. After Jurkat T cells were encapsulated with poly(allylamine hydrochloride) (PAH) and/or PSS-GNRs or PSS, most cells survived and could proliferate. Jurkat T cells encapsulated with a double layer of PSS-GNR/PAH (PSS-GNR/PAH@Jurkat) showed the highest rate of cell proliferation when compared to 24-h encapsulated cells. With the exception of IL-6, no significant induction of inflammatory cytokines (IL-2, IL-1β, and TNF-α) was observed. Interestingly, when encapsulated cells were co-cultured with THP-1 macrophages, co-cultures exhibited TNF-α production enhancement. However, the co-culture of THP-1 macrophage and PSS-GNR/PAH@Jurkat or PSS/PAH@Jurkat did not enhance TNF-α production. No significant inductions of IL-2, IL-1β, and IL-6 were detected. These data provide promising results, demonstrating the potential use of encapsulated PSS-GNR/PAH@Jurkat to provide a more inert T cell population for immunotherapy application and other biomedical applications.

Concurrent Fowlpox and Candidiasis Diseases in Backyard Chickens with Unusual Pox Lesions in the Bursa of Fabricius.

PubMed

Ogasawara, Fusae; Yamamoto, Yu; Sato, Yasuo; Fukunari, Kazuhiro; Murata, Ken-Ichi; Yaegashi, Gakuji; Goto, Makiko; Murakami, Ryukoh

2016-09-01

Concurrent fowlpox and candidiasis diseases occurred in a backyard chicken flock. Four deceased chickens (one Nagoya breed and three white silkie chickens) were examined for diagnosis. At necropsy, white curd-like plaques were observed in the crop. Fungal elements that stained positive for Candida albicans with immunohistochemistry were distributed throughout the tongue, choanal mucosa, esophagus, and crop. Typical fowlpox lesions, composed of proliferating epithelial cells with ballooning degeneration and viral intracytoplasmic inclusions, were observed in the conjunctiva, nasal mucosa, and skin around the cloaca. Interestingly, hyperplastic interfollicular epithelium with rare virus inclusions was observed in the bursa of Fabricius (BF). Some bursal follicles were replaced by proliferating epithelial cells. These proliferating cells immunohistochemically stained positive for cytokeratin. PCR and subsequent genetic sequencing detected the C. albicans gene in the crop, and fowlpox virus genes in the BF. These results indicate that this outbreak was a rare presentation of fowlpox in spontaneously infected chickens, with unusual pox lesions in the BF.

Disrupted cell cycle arrest and reduced proliferation in corneal fibroblasts from GCD2 patients: A potential role for altered autophagy flux

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

Choi, Seung-il; Dadakhujaev, Shorafidinkhuja; Maeng, Yong-Sun

Highlights: • Reduced cell proliferation in granular corneal dystrophy type 2. • Abnormal cell cycle arrest by defective autophagy. • Decreased Cyclin A1, B1, and D1 in Atg7 gene knockout cells. • Increase in p16 and p27 expressions were observed in Atg7 gene knockout cells. - Abstract: This study investigates the role of impaired proliferation, altered cell cycle arrest, and defective autophagy flux of corneal fibroblasts in granular corneal dystrophy type 2 (GCD2) pathogenesis. The proliferation rates of homozygous (HO) GCD2 corneal fibroblasts at 72 h, 96 h, and 120 h were significantly lower (1.102 ± 0.027, 1.397 ± 0.039,more » and 1.527 ± 0.056, respectively) than those observed for the wild-type (WT) controls (1.441 ± 0.029, 1.758 ± 0.043, and 2.003 ± 0.046, respectively). Flow cytometry indicated a decreased G{sub 1} cell cycle progression and the accumulation of cells in the S and G{sub 2}/M phases in GCD2 cells. These accumulations were associated with decreased levels of Cyclin A1, B1, and E1, and increased expression of p16 and p27. p21 and p53 expression was also significantly lower in GCD2 cells compared to the WT. Interestingly, treatment with the autophagy flux inhibitor, bafilomycin A{sub 1}, resulted in similarly decreased Cyclin A1, B1, D1, and p53 expression in WT fibroblasts. Furthermore, similar findings, including a decrease in Cyclin A1, B1, and D1 and an increase in p16 and p27 expression were observed in autophagy-related 7 (Atg7; known to be essential for autophagy) gene knockout cells. These data provide new insight concerning the role of autophagy in cell cycle arrest and cellular proliferation, uncovering a number of novel therapeutic possibilities for GCD2 treatment.« less

The BTK Inhibitor Ibrutinib (PCI-32765) Blocks Hairy Cell Leukaemia Survival, Proliferation and BCR Signalling: A New Therapeutic Approach

PubMed Central

Sivina, Mariela; Kreitman, Robert J.; Arons, Evgeny; Ravandi, Farhad; Burger, Jan A.

2014-01-01

B cell receptor (BCR) signalling plays a critical role in the progression of several B-cell malignancies, but its role in hairy cell leukaemia (HCL) is ambiguous. Bruton tyrosine kinase (BTK), a key player in BCR signalling, migration and adhesion, can be targeted with ibrutinib, a selective, irreversible BTK inhibitor. We analysed BTK expression and function in HCL and analysed the effects of ibrutinib on HCL cells. We demonstrated uniform BTK protein expression in HCL cells. Ibrutinib significantly inhibited HCL proliferation and cell cycle progression. Accordingly, ibrutinib also reduced HCL cell survival after BCR triggering with anti-immunoglobulins (A, G, and M) and abrogated the activation of kinases downstream of the BCR (PI3K and MAPK). Ibrutinib also inhibited BCR-dependent secretion of the chemokines CCL3 and CCL4 by HCL cells. Interestingly, ibrutinib inhibited CXCL12-induced signalling, a key pathway for bone marrow homing. Collectively, our data support the clinical development of ibrutinib in patients with HCL. PMID:24697238

microRNA 21-mediated suppression of Sprouty1 by Pokemon affects liver cancer cell growth and proliferation.

PubMed

Jin, Xiu-Li; Sun, Qin-Sheng; Liu, Feng; Yang, Hong-Wei; Liu, Min; Liu, Hong-Xia; Xu, Wei; Jiang, Yu-Yang

2013-07-01

Transcriptional repressor Pokemon is a critical factor in embryogenesis, development, cell proliferation, differentiation, and oncogenesis, thus behaving as an oncogene. Oncomine database suggests a potential correlation between the expressions of Pokemon and Sprouty1. This study investigated the regulatory role of Pokemon in Sprouty1 expression and the effect on liver cancer cell growth and proliferation, revealing a novel miR-21-mediated regulatory circuit. In normal (HL-7702) and cancer (QGY-7703) liver cell lines, Sprouty1 expression is inversely correlated with Pokemon levels. Targeted expression or siRNA-mediated silencing showed that Pokemon is a repressor of Sprouty1 expression at both mRNA and protein levels, but Pokemon cannot affect the promoter activity of Sprouty1. Sprouty1 is a target of miR-21 and interestingly, we found that miR-21 is up-regulated by Pokemon in liver cancer cells. Luciferase reporter assays showed that Pokemon up-regulated miR-21 transcription in a dose-dependent manner, and ChIP assay exhibited a direct binding of Pokemon to the miR-21 promoter at -747 to -399 bp. Site-directed mutagenesis of the GC boxes at -684 to -679 bp and -652 to -647 bp of miR-21 promoter abolished the regulatory activity by Pokemon. Furthermore, we found that the modulation of Pokemon and miR-21 expression affected the growth and proliferation of liver cancer cells QGY-7703. In summary, our findings demonstrate that Pokemon suppresses Sprouty1 expression through a miR-21-mediated mechanism, affecting the growth and proliferation of liver cancer cells. This study recognized miR-21 and Sprouty1 as novel targets of the Pokemon regulatory network. Copyright © 2013 Wiley Periodicals, Inc.

Evidence of K+ channel function in epithelial cell migration, proliferation, and repair

PubMed Central

Girault, Alban

2013-01-01

Efficient repair of epithelial tissue, which is frequently exposed to insults, is necessary to maintain its functional integrity. It is therefore necessary to better understand the biological and molecular determinants of tissue regeneration and to develop new strategies to promote epithelial repair. Interestingly, a growing body of evidence indicates that many members of the large and widely expressed family of K+ channels are involved in regulation of cell migration and proliferation, key processes of epithelial repair. First, we briefly summarize the complex mechanisms, including cell migration, proliferation, and differentiation, engaged after epithelial injury. We then present evidence implicating K+ channels in the regulation of these key repair processes. We also describe the mechanisms whereby K+ channels may control epithelial repair processes. In particular, changes in membrane potential, K+ concentration, cell volume, intracellular Ca2+, and signaling pathways following modulation of K+ channel activity, as well as physical interaction of K+ channels with the cytoskeleton or integrins are presented. Finally, we discuss the challenges to efficient, specific, and safe targeting of K+ channels for therapeutic applications to improve epithelial repair in vivo. PMID:24196531

Different effects of a novel CaO-MgO-SiO₂-based multiphase glass-ceramic on cell behaviors of normal and cancer cells in vitro.

PubMed

Zhang, Mengjiao; Chen, Xianchun; Pu, Ximing; Liao, Xiaoming; Huang, Zhongbing; Yin, Guangfu

2014-04-01

The effects in vitro of a novel multiphase glass-ceramic (with nominal composition of 43.19% CaO, 7.68% MgO, and 49.13% SiO2 in weight percent) on cell adhesion, proliferation, differentiation and ultrastructure of human osteosarcoma cell line MG63, mouse fibroblasts L929, and human lung adenocarcinoma epithelial cell line A549 were investigated in this research. Scanning electron microscopy (SEM) micrographs revealed that the surface morphology of this glass-ceramic was beneficial to cell adhesion. The glass-ceramic extracts at certain concentrations could stimulate the proliferation and differentiation of MG63 and L929 cells, whereas inhibit A549 proliferation, which might be resulted from the released Si ions. In addition, when cultured with 0.1mg/mL glass-ceramic powder suspension, the cell ultrastructure of MG63 showed abundant organelles and L929 displayed the phenomena of cellular stress response. While more interestingly, A549 exhibited chromatin condensation, mitochondria swell and RER expansion, which was presumed to be early signs of apoptosis. These results suggest that this novel CaO-MgO-SiO2-based multiphase glass-ceramic has potential for bone regeneration and tissue engineering applications. Copyright © 2013 Elsevier B.V. All rights reserved.

Leptin influences estrogen metabolism and accelerates prostate cell proliferation.

PubMed

Habib, Christine N; Al-Abd, Ahmed M; Tolba, Mai F; Khalifa, Amani E; Khedr, Alaa; Mosli, Hisham A; Abdel-Naim, Ashraf B

2015-01-15

The present study was designed to investigate the effect of leptin on estrogen metabolism in prostatic cells. Malignant (PC-3) and benign (BPH-1) human prostate cells were treated with 17-β-hydroxyestradiol (1 μM) alone or in combination with leptin (0.4, 4, 40 ng/ml) for 72 h. Cell proliferation assay, immunocytochemical staining of estrogen receptor (ER), liquid chromatography-tandem mass spectrometry method (LC-MS) and semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) were used. Cell proliferation assay demonstrated that leptin caused significant growth potentiation in both cells. Immunocytochemical staining showed that leptin significantly increased the expression of ER-α and decreased that of ER-β in PC-3 cells. LC-MS method revealed that leptin increased the concentration 4-hydroxyestrone and/or decreased that of 2-methoxyestradiol, 4-methoxyestradiol and 2-methoxyestrone. Interestingly, RT-PCR showed that leptin significantly up-regulated the expression of aromatase and cytochrome P450 1B1 (CYP1B1) enzymes; however down-regulated the expression of catechol-o-methyltransferase (COMT) enzyme. These data indicate that leptin-induced proliferative effect in prostate cells might be partly attributed to estrogen metabolism. Thus, leptin might be a novel target for therapeutic intervention in prostatic disorders. Copyright © 2014 Elsevier Inc. All rights reserved.

Cross-Talk Between Mitochondrial Fusion and the Hippo Pathway in Controlling Cell Proliferation During Drosophila Development.

PubMed

Deng, Qiannan; Guo, Ting; Zhou, Xiu; Xi, Yongmei; Yang, Xiaohang; Ge, Wanzhong

2016-08-01

Cell proliferation and tissue growth depend on the coordinated regulation of multiple signaling molecules and pathways during animal development. Previous studies have linked mitochondrial function and the Hippo signaling pathway in growth control. However, the underlying molecular mechanisms are not fully understood. Here we identify a Drosophila mitochondrial inner membrane protein ChChd3 as a novel regulator for tissue growth. Loss of ChChd3 leads to tissue undergrowth and cell proliferation defects. ChChd3 is required for mitochondrial fusion and removal of ChChd3 increases mitochondrial fragmentation. ChChd3 is another mitochondrial target of the Hippo pathway, although it is only partially required for Hippo pathway-mediated overgrowth. Interestingly, lack of ChChd3 leads to inactivation of Hippo activity under normal development, which is also dependent on the transcriptional coactivator Yorkie (Yki). Furthermore, loss of ChChd3 induces oxidative stress and activates the JNK pathway. In addition, depletion of other mitochondrial fusion components, Opa1 or Marf, inactivates the Hippo pathway as well. Taken together, we propose that there is a cross-talk between mitochondrial fusion and the Hippo pathway, which is essential in controlling cell proliferation and tissue homeostasis in Drosophila. Copyright © 2016 by the Genetics Society of America.

Combined platelet and plasma derivatives enhance proliferation of stem/progenitor cells maintaining their differentiation potential.

PubMed

Muraglia, Anita; Todeschi, Maria Rosa; Papait, Andrea; Poggi, Alessandro; Spanò, Raffaele; Strada, Paolo; Cancedda, Ranieri; Mastrogiacomo, Maddalena

2015-12-01

Platelet derivatives have been proposed as alternatives to animal sera given that for cell therapy applications, the use of fetal bovine/calf serum (FBS/FCS) is subjected to severe limitations for safety and ethical concerns. We developed a cell culture medium additive obtained by the combination of two blood-derived standardized components. A platelet lysate (PL) and a platelet-poor plasma (PPP) were produced in a lyophilized form. Each component was characterized for its growth factor content (platelet-derived growth factor-BB/vascular endothelial growth factor). PL and PPP were used as single components or in combination in different ratio at cumulative 5% final concentration in the culture medium. The single components were less effective than the component combination. In primary cell cultures (bone marrow stromal cells, adipose derived adult stem cells, osteoblasts, chondrocytes, umbilical cord-derived mesenchymal stromal cells, lymphocytes), the PL/PPP supplement promoted an increased cell proliferation in respect to the standard FCS culture in a dose-dependent manner, maintaining the cell functionality, clonogenicity, phenotype and differentiative properties throughout the culture. At a different component ratio, the supplement was also used to support proliferation of a cell line (U-937). The PL/PPP supplement is an efficient cell culture medium additive that can replace FCS to promote cell proliferation. It can outdo FCS, especially when adopted in primary cultures from tissue biopsies. Moreover, the dual component nature of the supplement allows the researcher to determine the more appropriate ratio of the two components for the nutritional and functional requirements of the cell type of interest. Copyright © 2015 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Deregulation of the CEACAM expression pattern causes undifferentiated cell growth in human lung adenocarcinoma cells.

PubMed

Singer, Bernhard B; Scheffrahn, Inka; Kammerer, Robert; Suttorp, Norbert; Ergun, Suleyman; Slevogt, Hortense

2010-01-18

CEACAM1, CEA/CEACAM5, and CEACAM6 are cell adhesion molecules (CAMs) of the carcinoembryonic antigen (CEA) family that have been shown to be deregulated in lung cancer and in up to 50% of all human cancers. However, little is known about the functional impact of these molecules on undifferentiated cell growth and tumor progression. Here we demonstrate that cell surface expression of CEACAM1 on confluent A549 human lung adenocarcinoma cells plays a critical role in differentiated, contact-inhibited cell growth. Interestingly, CEACAM1-L, but not CEACAM1-S, negatively regulates proliferation via its ITIM domain, while in proliferating cells no CEACAM expression is detectable. Furthermore, we show for the first time that CEACAM6 acts as an inducer of cellular proliferation in A549 cells, likely by interfering with the contact-inhibiting signal triggered by CEACAM1-4L, leading to undifferentiated anchorage-independent cell growth. We also found that A549 cells expressed significant amounts of non-membrane anchored variants of CEACAM5 and CEACAM6, representing a putative source for the increased CEACAM5/6 serum levels frequently found in lung cancer patients. Taken together, our data suggest that post-confluent contact inhibition is established and maintained by CEACAM1-4L, but disturbances of CEACAM1 signalling by CEACAM1-4S and other CEACAMs lead to undifferentiated cell growth and malignant transformation.

Stem Cells and Regenerative Medicine: Myth or Reality of the 21th Century

PubMed Central

Stoltz, J.-F.; de Isla, N.; Li, Y. P.; Bensoussan, D.; Zhang, L.; Huselstein, C.; Chen, Y.; Decot, V.; Magdalou, J.; Li, N.; Reppel, L.; He, Y.

2015-01-01

Since the 1960s and the therapeutic use of hematopoietic stem cells of bone marrow origin, there has been an increasing interest in the study of undifferentiated progenitors that have the ability to proliferate and differentiate into various tissues. Stem cells (SC) with different potency can be isolated and characterised. Despite the promise of embryonic stem cells, in many cases, adult or even fetal stem cells provide a more interesting approach for clinical applications. It is undeniable that mesenchymal stem cells (MSC) from bone marrow, adipose tissue, or Wharton's Jelly are of potential interest for clinical applications in regenerative medicine because they are easily available without ethical problems for their uses. During the last 10 years, these multipotent cells have generated considerable interest and have particularly been shown to escape to allogeneic immune response and be capable of immunomodulatory activity. These properties may be of a great interest for regenerative medicine. Different clinical applications are under study (cardiac insufficiency, atherosclerosis, stroke, bone and cartilage deterioration, diabetes, urology, liver, ophthalmology, and organ's reconstruction). This review focuses mainly on tissue and organ regeneration using SC and in particular MSC. PMID:26300923

Order-of-magnitude estimates of latency (time to appearance) and refill time of a cancer from a single cancer 'stem' cell compared by an exponential and a logistic equation.

PubMed

Anderson, Ken M; Rubenstein, Marvin; Guinan, Patrick; Patel, Minu

2012-01-01

The time required before a mass of cancer cells considered to have originated from a single malignantly transformed cancer 'stem' cell reaches a certain number has not been studied. Applications might include determination of the time the cell mass reaches a size that can be detected by X-rays or physical examination or modeling growth rates in vitro in order to compare with other models or established data. We employed a simple logarithmic equation and a common logistic equation incorporating 'feedback' for unknown variables of cell birth, growth, division, and death that can be used to model cell proliferation. It can be used in association with free or commercial statistical software. Results with these two equations, varying the proliferation rate, nominally reduced by generational cell loss, are presented in two tables. The resulting equation, instructions, examples, and necessary mathematical software are available in the online appendix, where several parameters of interest can be modified by the reader www.uic.edu/nursing/publicationsupplements/tobillion_Anderson_Rubenstein_Guinan_Patel1.pdf. Reducing the proliferation rate by whatever alterations employed, markedly increases the time to reach 10(9) cells originating from an initial progenitor. In thinking about multistep oncogenesis, it is useful to consider the profound effect that variations in the effective proliferation rate may have during cancer development. This can be approached with the proposed equation, which is easy to use and available to further peer fine-tuning to be used in future modeling of cell growth.

Aurora kinase inhibitor AZD1152 has an additional effect of platinum on a sequential application at the human ovarian cancer cell line SKOV3.

PubMed

Ma, Yaxi; Weimer, Jörg; Fredrik, Regina; Adam-Klages, Sabine; Sebens, Susanne; Caliebe, Amke; Hilpert, Felix; Eckmann-Scholz, Christel; Arnold, Norbert; Schem, Christian

2013-07-01

The treatment of ovarian tumors is carried out with platinum medicine which can lead to incompatibilities or resistances. Thus, it is of great interest to check new medicine suitability for its application. AZD1152 is an Aurora kinase inhibitor predominantly works against Aurora kinase B involved in the chromosome segregation. Cells become polyploidy and reduce the proliferation by this impairment. To investigate whether AZD1152, may play a role in the treatment of ovarian carcinoma we serving it to the cisplatinum-resistant cell line SKOV3 alone and in combination with platinum. We look at the proliferation, the ploidy, the phases of cell cycle and the apoptosis activity of the cells. We could show that the combination of both medicines in the preclinical experiment produces a working advantage.

The laminA/NF-Y protein complex reveals an unknown transcriptional mechanism on cell proliferation

PubMed Central

Mancone, Carmine; Regazzo, Giulia; Spagnuolo, Manuela; Alonzi, Tonino; Carlomosti, Fabrizio; Lucia, Maria Dell’Anna; Dell, Giulia 'Omo; Picardo, Mauro; Ciana, Paolo; Capogrossi, Maurizio C; Tripodi, Marco; Magenta, Alessandra; Giulia, Maria Rizzo; Gurtner, Aymone; Piaggio, Giulia

2017-01-01

Lamin A is a component of the nuclear matrix that also controls proliferation by largely unknown mechanisms. NF-Y is a ubiquitous protein involved in cell proliferation composed of three subunits (-YA -YB -YC) all required for the DNA binding and transactivation activity. To get clues on new NF-Y partner(s) we performed a mass spectrometry screening of proteins that co-precipitate with the regulatory subunit of the complex, NF-YA. By this screening we identified lamin A as a novel putative NF-Y interactor. Co-immunoprecipitation experiments and confocal analysis confirmed the interaction between the two endogenous proteins. Interestingly, this association occurs on euchromatin regions, too. ChIP experiments demonstrate lamin A enrichment in several promoter regions of cell cycle related genes in a NF-Y dependent manner. Gain and loss of function experiments reveal that lamin A counteracts NF-Y transcriptional activity. Taking advantage of a recently generated transgenic reporter mouse, called MITO-Luc, in which an NF-Y–dependent promoter controls luciferase expression, we demonstrate that lamin A counteracts NF-Y transcriptional activity not only in culture cells but also in living animals. Altogether, our data demonstrate the occurrence of lamin A/NF-Y interaction and suggest a possible role of this protein complex in regulation of NF-Y function in cell proliferation. PMID:27793050

Analysis of cardiomyocyte movement in the developing murine heart

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

Hashimoto, Hisayuki; Yuasa, Shinsuke, E-mail: yuasa@a8.keio.jp; Tabata, Hidenori

The precise assemblage of several types of cardiac precursors controls heart organogenesis. The cardiac precursors show dynamic movement during early development and then form the complicated heart structure. However, cardiomyocyte movements inside the newly organized mammalian heart remain unclear. We previously established the method of ex vivo time-lapse imaging of the murine heart to study cardiomyocyte behavior by using the Fucci (fluorescent ubiquitination-based cell cycle indicator) system, which can effectively label individual G1, S/G2/M, and G1/S-transition phase nuclei in living cardiomyocytes as red, green, and yellow, respectively. Global analysis of gene expression in Fucci green positive ventricular cardiomyocytes confirmed that cellmore » cycle regulatory genes expressed in G1/S, S, G2/M, and M phase transitions were upregulated. Interestingly, pathway analysis revealed that many genes related to the cell cycle were significantly upregulated in the Fucci green positive ventricular cardiomyocytes, while only a small number of genes related to cell motility were upregulated. Time-lapse imaging showed that murine proliferating cardiomyocytes did not exhibit dynamic movement inside the heart, but stayed on site after entering the cell cycle. - Highlights: • We directly visualized cardiomyocyte movement inside the developing murine heart. • Cell cycle related genes were upregulated in the proliferating cardiomyocytes. • Time-lapse imaging revealed that proliferating murine cardiomyocytes stayed in place. • Murine ventricular cardiomyocytes proliferate on site during development.« less

Nociceptin/orphanin FQ antagonizes lipopolysaccharide-stimulated proliferation, migration and inflammatory signaling in human glioblastoma U87 cells.

PubMed

Bedini, Andrea; Baiula, Monica; Vincelli, Gabriele; Formaggio, Francesco; Lombardi, Sara; Caprini, Marco; Spampinato, Santi

2017-09-15

Glioblastoma is among the most aggressive brain tumors and has an exceedingly poor prognosis. Recently, the importance of the tumor microenvironment in glioblastoma cell growth and progression has been emphasized. Toll-like receptor 4 (TLR4) recognizes bacterial lipopolysaccharide (LPS) and endogenous ligands originating from dying cells or the extracellular matrix involved in host defense and in inflammation. G-protein coupled receptors (GPCRs) have gained interest in anti-tumor drug discovery due to the role that they directly or indirectly play by transactivating other receptors, causing cell migration and proliferation. A proteomic analysis showed that the nociceptin receptor (NOPr) is among the GPCRs significantly expressed in glioblastoma cells, including U87 cells. We describe a novel role of the peptide nociceptin (N/OFQ), the endogenous ligand of the NOPr that counteracts cell migration, proliferation and increase in IL-1β mRNA elicited by LPS via TLR4 in U87 glioblastoma cells. Signaling pathways through which N/OFQ inhibits LPS-mediated cell migration and elevation of [Ca 2+ ] i require β-arrestin 2 and are sensitive to TNFR-associated factor 6, c-Src and protein kinase C (PKC). LPS-induced cell proliferation and increase in IL-1β mRNA are counteracted by N/OFQ via β-arrestin 2, PKC and extracellular signal-regulated kinase 1/2; furthermore, the contributions of the transcription factors NF-kB and AP-1 were investigated. Independent of LPS, N/OFQ induces a significant increase in cell apoptosis. Contrary to what was observed in other cell models, a prolonged exposure to this endotoxin did not promote any tolerance of the cellular effects above described, including NOPr down-regulation while N/OFQ loses its inhibitory role. Copyright © 2017 Elsevier Inc. All rights reserved.

Selective modulation of endoplasmic reticulum stress markers in prostate cancer cells by a standardized mangosteen fruit extract.

PubMed

Li, Gongbo; Petiwala, Sakina M; Pierce, Dana R; Nonn, Larisa; Johnson, Jeremy J

2013-01-01

The increased proliferation of cancer cells is directly dependent on the increased activity of the endoplasmic reticulum (ER) machinery which is responsible for protein folding, assembly, and transport. In fact, it is so critical that perturbations in the endoplasmic reticulum can lead to apoptosis. This carefully regulated organelle represents a unique target of cancer cells while sparing healthy cells. In this study, a standardized mangosteen fruit extract (MFE) was evaluated for modulating ER stress proteins in prostate cancer. Two human prostate cancer cell lines, 22Rv1 and LNCaP, and prostate epithelial cells (PrECs) procured from two patients undergoing radical prostatectomy were treated with MFE. Flow cytometry, MTT, BrdU and Western blot were used to evaluate cell apoptosis, viability, proliferation and ER stress. Next, we evaluated MFE for microsomal stability and anti-cancer activity in nude mice. MFE induced apoptosis, decreased viability and proliferation in prostate cancer cells. MFE increased the expression of ER stress proteins. Interestingly, MFE selectively promotes ER stress in prostate cancer cells while sparing PrECs. MFE suppressed tumor growth in a xenograft tumor model without obvious toxicity. Mangosteen fruit extract selectively promotes endoplasmic reticulum stress in cancer cells while sparing non-tumorigenic prostate epithelial cells. Furthermore, in an in vivo setting mangosteen fruit extract significantly reduces xenograft tumor formation.

Selective Modulation of Endoplasmic Reticulum Stress Markers in Prostate Cancer Cells by a Standardized Mangosteen Fruit Extract

PubMed Central

Li, Gongbo; Petiwala, Sakina M.; Pierce, Dana R.; Nonn, Larisa; Johnson, Jeremy J.

2013-01-01

The increased proliferation of cancer cells is directly dependent on the increased activity of the endoplasmic reticulum (ER) machinery which is responsible for protein folding, assembly, and transport. In fact, it is so critical that perturbations in the endoplasmic reticulum can lead to apoptosis. This carefully regulated organelle represents a unique target of cancer cells while sparing healthy cells. In this study, a standardized mangosteen fruit extract (MFE) was evaluated for modulating ER stress proteins in prostate cancer. Two human prostate cancer cell lines, 22Rv1 and LNCaP, and prostate epithelial cells (PrECs) procured from two patients undergoing radical prostatectomy were treated with MFE. Flow cytometry, MTT, BrdU and Western blot were used to evaluate cell apoptosis, viability, proliferation and ER stress. Next, we evaluated MFE for microsomal stability and anti-cancer activity in nude mice. MFE induced apoptosis, decreased viability and proliferation in prostate cancer cells. MFE increased the expression of ER stress proteins. Interestingly, MFE selectively promotes ER stress in prostate cancer cells while sparing PrECs. MFE suppressed tumor growth in a xenograft tumor model without obvious toxicity. Mangosteen fruit extract selectively promotes endoplasmic reticulum stress in cancer cells while sparing non-tumorigenic prostate epithelial cells. Furthermore, in an in vivo setting mangosteen fruit extract significantly reduces xenograft tumor formation. PMID:24367485

Meristematic competence is disrupted by microgravity, real or simulated, in seedlings and cultured cells of Arabidopsis

NASA Astrophysics Data System (ADS)

Medina, Francisco Javier; Herranz, Raul; Van Loon, ing.. Jack J. W. A.; Kiss, John; Valbuena, Miguel A.; Youssef, Khaled

In actively proliferating plant cells, the rate of cell proliferation is strictly coordinated with cell growth, and this coordination is called “meristematic competence”. Cell proliferation consists of the adequate progression of the cell division cycle throughout specific regulatory checkpoints, and cell growth consists of reaching the critical size making possible cell division, based on the increase of biomass, essentially by means of protein synthesis. There are two cellular models in which these processes can be studied, namely the meristematic tissues of plants and seedlings and the in vitro suspension cell cultures. Meristems are essential for the determination of the developmental pattern of the plant, which is primarily based on the balance between proliferating (meristematic) and differentiated cells. Auxin is a fundamental phytohormone, responsible for the maintenance of meristematic competence and for the control of the rate of differentiation. We first studied the proliferating activity of root meristematic cells in the International Space Station (ISS) and in a random positioning machine (RPM), a ground-based device for simulated microgravity. The result in both experiments was the increase of mitotic activity (cell proliferation) and the depletion of ribosome synthesis (cell growth), that is, the disruption of meristematic competence. We found these effects associated with changes in the auxin levels and polar transport, which is related to the role of auxin as a mediator of the transduction of the gravitropic signal sensed in the root columella. We plan to advance in the investigation of mechanisms of the auxin control of meristematic competence in microgravity conditions in a new experiment, “Seedling Growth”, to be performed in the ISS. We will use mutants of the auxin transport pathway and we will also test the potential activating role of red light, known to be a cell proliferation and gene expression enhancer. The role played by phytochromes, the red light receptors, will be analyzed by using specific mutants. However, interestingly, studies performed on synchronized in vitro cell cultures grown in the RPM in absence of auxin transport alterations and of any change in the auxin levels, showed also disruption of meristematic competence. The cell cycle was shortened (specifically the G2 period) and ribosome production was depleted, as shown by flow cytometry, immunocytochemistry and qPCR estimation of the expression of relevant genes. This strongly suggests that the effects of altered gravity on cell growth and proliferation are not only the consequence of the transduction of the gravitropic signal mediated by auxin, but they may also be achieved using additional mechanisms of gravity sensing and additional transduction mediators. Supported by ESA, NASA and Spanish “Plan Nacional de I+D+I” (AYA2012-33982).

Insulin-like growth factor 1 promotes the proliferation and committed differentiation of human dental pulp stem cells through MAPK pathways.

PubMed

Lv, Taohong; Wu, Yongzheng; Mu, Chao; Liu, Genxia; Yan, Ming; Xu, Xiangqin; Wu, Huayin; Du, Jinyin; Yu, Jinhua; Mu, Jinquan

2016-12-01

Insulin-like growth factor 1 (IGF-1) is a broad-spectrum growth-promoting factor that plays a key role in natural tooth development. Human dental pulp stem cells (hDPSCs) are multipotent and can influence the reparative regeneration of dental pulp and dentin. This study was designed to evaluate the effects of IGF-1 on the proliferation and differentiation of human dental pulp stem cells. HDPSCs were isolated and purified from human dental pulps. The proliferation and osteo/odontogenic differentiation of hDPSCs treated with 100ng/ml exogenous IGF-1 were subsequently investigated. MTT assays revealed that IGF-1 enhanced the proliferation of hDPSCs. ALP activity in IGF-1-treated group was obviously enhanced compared to the control group from days 3 to 9. Alizarin red staining revealed that the IGF-1-treated cells contained a greater number of mineralization nodules and had higher calcium concentrations. Moreover, western blot and qRT-PCR analyses demonstrated that the expression levels of several osteogenic genes (e.g., RUNX2, OSX, and OCN) and an odontoblast-specific marker (DSPP) were significantly up-regulated in IGF-1-treated hDPSCs as compared with untreated cells (P<0.01). Interestingly, the expression of phospho-ERK and phospho-p38 were also up-regulated, indicating that the MAPK signaling pathway is activated during the differentiation of hDPSCs. IGF-1 can promote the proliferation and osteo/odontogenic differentiation of hDPSCs by activating MAPK pathways. Copyright © 2016 Elsevier Ltd. All rights reserved.

Knockdown of microtubule actin crosslinking factor 1 inhibits cell proliferation in MC3T3-E1 osteoblastic cells

PubMed Central

Hu, Lifang; Su, Peihong; Li, Runzhi; Yan, Kun; Chen, Zhihao; Shang, Peng; Qian, Airong

2015-01-01

Microtubule actin crosslinking factor 1 (MACF1), a widely expressed cytoskeletal linker, plays important roles in various cells by regulating cytoskeleton dynamics. However, its role in osteoblastic cells is not well understood. Based on our previous findings that the association of MACF1 with F-actin and microtubules in osteoblast-like cells was altered under magnetic force conditions, here, by adopting a stable MACF1-knockdown MC3T3-E1 osteoblastic cell line, we found that MACF1 knockdown induced large cells with a binuclear/multinuclear structure. Further, immunofluorescence staining showed disorganization of F-actin and microtubules in MACF1-knockdown cells. Cell counting revealed significant decrease of cell proliferation and cell cycle analysis showed an S phase cell cycle arrest in MACF1-knockdown cells. Moreover and interestingly, MACF1 knockdown showed a potential effect on cellular MTT reduction activity and mitochondrial content, suggesting an impact on cellular metabolic activity. These results together indicate an important role of MACF1 in regulating osteoblastic cell morphology and function. [BMB Reports 2015; 48(10): 583-588] PMID:26277981

Knockdown of microtubule actin crosslinking factor 1 inhibits cell proliferation in MC3T3-E1 osteoblastic cells.

PubMed

Hu, Lifang; Su, Peihong; Li, Runzhi; Yan, Kun; Chen, Zhihao; Shang, Peng; Qian, Airong

2015-10-01

Microtubule actin crosslinking factor 1 (MACF1), a widely expressed cytoskeletal linker, plays important roles in various cells by regulating cytoskeleton dynamics. However, its role in osteoblastic cells is not well understood. Based on our previous findings that the association of MACF1 with F-actin and microtubules in osteoblast-like cells was altered under magnetic force conditions, here, by adopting a stable MACF1-knockdown MC3T3-E1 osteoblastic cell line, we found that MACF1 knockdown induced large cells with a binuclear/multinuclear structure. Further, immunofluorescence staining showed disorganization of F-actin and microtubules in MACF1-knockdown cells. Cell counting revealed significant decrease of cell proliferation and cell cycle analysis showed an S phase cell cycle arrest in MACF1-knockdown cells. Moreover and interestingly, MACF1 knockdown showed a potential effect on cellular MTT reduction activity and mitochondrial content, suggesting an impact on cellular metabolic activity. These results together indicate an important role of MACF1 in regulating osteoblastic cell morphology and function.

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

Cho, Seong-Jun; Kang, Hana; Kim, Min Young

Purpose: To determine how low-dose ionizing radiation (LDIR) regulates B lympho-proliferation and its molecular mechanism related with Ikaros, transcription factor. Methods and Materials: Splenocytes and IM-9 cells were uniformly irradiated with various doses of a {sup 137}Cs γ-source, and cell proliferation was analyzed. To determine the LDIR-specific phosphorylation of Ikaros, immunoprecipitation and Western blot analysis were performed. To investigate the physiologic function of LDIR-mediatied Ikaros phosphorylation, Ikaros mutants at phosphorylation sites were generated, and cell cycle analysis was performed. Results: First, we found that LDIR enhances B lymphoblast proliferation in an Ikaros-dependent manner. Moreover, we found that LDIR elevates the phosphorylationmore » level of Ikaros protein. Interestingly, we showed that CK2 and AKT are involved in LDIR-induced Ikaros phosphorylation and capable of regulating DNA binding activity of Ikaros via specific phosphorylation. Finally, we identified LDIR-specific Ikaros phosphorylation sites at S391/S393 and showed that the Ikaros phosphorylations at these sites control Ikaros's ability to regulate G1/S cell cycle progression. Conclusion: Low-dose ionizing radiation specifically phosphorylates Ikaros protein at Ser 391/393 residues to regulate cell cycle progression in B lymphoblast.« less

T-kininogen, a cystatin-like molecule, inhibits ERK-dependent lymphocyte proliferation.

PubMed

Acuña-Castillo, Claudio; Aravena, Mauricio; Leiva-Salcedo, Elías; Pérez, Viviana; Gómez, Christian; Sabaj, Valeria; Nishimura, Sumiyo; Pérez, Claudio; Colombo, Alicia; Walter, Robin; Sierra, Felipe

2005-12-01

Plasma levels of kininogens increase with age in both rats and humans. Kininogens are inhibitors of cysteine proteinases, and filarial cysteine proteinase inhibitors (cystatins) reduce the proliferation of T cells. We evaluated whether T-kininogen (T-KG) might mimic this effect, and here we present data indicating that exposure of either rat splenocytes or Jurkat cells to purified T-KG results in inhibition of both ERK activation and [(3)H]-thymidine incorporation, both basal and in response to ConA or PHA. Interestingly, T-KG did not impair [(3)H]-thymidine incorporation in response to IL-2, which requires primarily the activation of the JNK and Jak/STAT pathways. These effects were neither the consequence of increased cell death, nor required the activity of kinin receptors. Furthermore, when T cell receptor proximal events were bypassed by the use of PMA plus Calcium ionophore, T-KG no longer inhibited ERK activation, suggesting that inhibition occurs upstream of these events, possibly at the level of membrane associated signal transduction molecules. We conclude that, like filarial cystatins, T-KG inhibits ERK-dependent T cell proliferation, and these observations suggest a possible role for T-KG in immunosenescence.

Estrogenic activity of osthole and imperatorin in MCF-7 cells and their osteoblastic effects in Saos-2 cells.

PubMed

Jia, Min; Li, Yuan; Xin, Hai-Liang; Hou, Ting-Ting; Zhang, Nai-Dai; Xu, Hong-Tao; Zhang, Qiao-Yan; Qin, Lu-Ping

2016-06-01

There is an increasing interest in phytoestrogens due to their potential medical usage in hormone replacement therapy (HRT). The present study was designed to investigate the in vitro effects of estrogen-like activities of two widespread coumarins, osthole and imperatorin, using the MCF-7 cell proliferation assay and their alkaline phosphatase (ALP) activities in osteoblasts Saos-2 cells. The two compounds were found to strongly stimulate the proliferation of MCF-7 cells. The estrogen receptor-regulated ERα, progesterone receptor (PR) and PS2 mRNA levels were increased by treatment with osthole and imperatorin. All these effects were significantly inhibited by the specific estrogen receptor antagonist ICI182, 780. Cell cycle analysis revealed that their proliferation stimulatory effect was associated with a marked increase in the number of MCF-7 cells in S phase, which was similar to that observed with estradiol. It was also observed that they significantly increased ALP activity, which was reversed by ICI182,780. These results suggested that osthole and imperatorin could stimulate osteoblastic activity by displaying estrogenic properties or through the ER pathway. In conclusion, osthole and imperatorin may represent new pharmacological tools for the treatment of osteoporosis. Copyright © 2016 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

SHIP deficiency enhances HSC proliferation and survival but compromises homing and repopulation

PubMed Central

Desponts, Caroline; Hazen, Amy L.; Paraiso, Kim H. T.; Kerr, William G.

2006-01-01

The SH2 domain–containing inositol 5′-phosphatase-1 (SHIP) has the potential to modulate multiple signaling pathways downstream of receptors that impact hematopoietic stem cell (HSC) biology. Therefore, we postulated that SHIP might play an important role in HSC homeostasis and function. Consistent with this hypothesis, HSC proliferation and numbers are increased in SHIP–/– mice. Despite expansion of the compartment, SHIP–/– HSCs exhibit reduced capacity for long-term repopulation. Interestingly, we observe that SHIP–/– stem/progenitor cells home inefficiently to bone marrow (BM), and consistent with this finding, have reduced surface levels of both CXCR4 and vascular cell adhesion marker-1 (VCAM-1). These studies demonstrate that SHIP is critical for normal HSC function, homeostasis, and homing. PMID:16467196

Cucurbitacin B purified from Ecballium elaterium (L.) A. Rich from Tunisia inhibits α5β1 integrin-mediated adhesion, migration, proliferation of human glioblastoma cell line and angiogenesis.

PubMed

Touihri-Barakati, Imen; Kallech-Ziri, Olfa; Ayadi, Wiem; Kovacic, Hervé; Hanchi, Belgacem; Hosni, Karim; Luis, José

2017-02-15

Integrins are essential protagonists in the complex multistep process of cancer progression and are thus attractive targets for the development of anticancer agents. Cucurbitacin B, a triterpenoid purified from the leaves of Tunisian Ecballium elaterium exhibited an anticancer effect and displayed anti-integrin activity on human glioblastoma U87 cells, without being cytotoxic at concentrations up to 500nM. Here we show that cucurbitacin B affected the adhesion and migration of U87 cells to fibronectin in a dose-dependent manner with IC50 values of 86.2nM and 84.6nM, respectively. Time-lapse videomicroscopy showed that cucurbitacin B significantly reduced U87 cells motility and affected directional persistence. Cucurbitacin B also inhibited proliferation with IC50 value of 70.1nM using Crystal Violet assay. Moreover, cucurbitacin B efficiently inhibited in vitro human microvascular endothelial cells (HMEC) angiogenesis with concentration up to 10nM. Interestingly, we demonstrate for the first time that this effect was specifically mediated by α5β1 integrins. These findings reveal a novel mechanism of action for cucurbitacin B, which displays a potential interest as a specific anti-integrin drug. Copyright © 2017 Elsevier B.V. All rights reserved.

The antidepressant effects of running and escitalopram are associated with levels of hippocampal NPY and Y1 receptor but not cell proliferation in a rat model of depression.

PubMed

Bjørnebekk, Astrid; Mathé, Aleksander A; Brené, Stefan

2010-07-01

One hypothesis of depression is that it is caused by reduced neuronal plasticity including hippocampal neurogenesis. In this study, we compared the effects of three long-term antidepressant treatments: escitalopram, voluntary running, and their combination on hippocampal cell proliferation, NPY and the NPY-Y1 receptor mRNAs, targets assumed to be important for hippocampal plasticity and mood disorders. An animal model of depression, the Flinders Sensitive Line (FSL) rat, was used and female rats were chosen because the majority of the depressed population is females. We investigated if these treatments were correlated to immobility, swimming, and climbing behaviors, which are associated with an overall, serotonergic-like and noradrenergic-like antidepressant response, in the Porsolt swim test (PST). Interestingly, while escitalopram, running and their combination increased the number of hippocampal BrdU immunoreactive cells, the antidepressant-like effect was only detected in the running group and the group with access both to running wheel and escitalopram. Hippocampal NPY mRNA and the NPY-Y1 receptor mRNA were elevated by running and the combined treatment. Moreover, correlations were detected between NPY mRNA levels and climbing and cell proliferation and NPY-Y1 receptor mRNA levels and swimming. Our results suggest that increased cell proliferation is not necessarily associated with an antidepressant effect. However, treatments that were associated with an antidepressant-like effect did regulate hippocampal levels of mRNAs encoding NPY and/or the NPY-Y1 receptor and support the notion that NPY can stimulate cell proliferation and induce an antidepressant-like response. Copyright 2009 Wiley-Liss, Inc.

Pharmacological activation of CB2 receptors counteracts the deleterious effect of ethanol on cell proliferation in the main neurogenic zones of the adult rat brain.

PubMed

Rivera, Patricia; Blanco, Eduardo; Bindila, Laura; Alen, Francisco; Vargas, Antonio; Rubio, Leticia; Pavón, Francisco J; Serrano, Antonia; Lutz, Beat; Rodríguez de Fonseca, Fernando; Suárez, Juan

2015-01-01

Chronic alcohol exposure reduces endocannabinoid activity and disrupts adult neurogenesis in rodents, which results in structural and functional alterations. Cannabinoid receptor agonists promote adult neural progenitor cell (NPC) proliferation. We evaluated the protective effects of the selective CB1 receptor agonist ACEA, the selective CB2 receptor agonist JWH133 and the fatty-acid amide-hydrolase (FAAH) inhibitor URB597, which enhances endocannabinoid receptor activity, on NPC proliferation in rats with forced consumption of ethanol (10%) or sucrose liquid diets for 2 weeks. We performed immunohistochemical and stereological analyses of cells expressing the mitotic phosphorylation of histone-3 (phospho-H3+) and the replicating cell DNA marker 5-bromo-2'-deoxyuridine (BrdU+) in the main neurogenic zones of adult brain: subgranular zone of dentate gyrus (SGZ), subventricular zone of lateral ventricles (SVZ) and hypothalamus. Animals were allowed ad libitum ethanol intake (7.3 ± 1.1 g/kg/day) after a controlled isocaloric pair-feeding period of sucrose and alcoholic diets. Alcohol intake reduced the number of BrdU+ cells in SGZ, SVZ, and hypothalamus. The treatments (URB597, ACEA, JWH133) exerted a differential increase in alcohol consumption over time, but JWH133 specifically counteracted the deleterious effect of ethanol on NPC proliferation in the SVZ and SGZ, and ACEA reversed this effect in the SGZ only. JWH133 also induced an increased number of BrdU+ cells expressing neuron-specific β3-tubulin in the SVZ and SGZ. These results indicated that the specific activation of CB2 receptors rescued alcohol-induced impaired NPC proliferation, which is a potential clinical interest for the risk of neural damage in alcohol dependence.

Pharmacological activation of CB2 receptors counteracts the deleterious effect of ethanol on cell proliferation in the main neurogenic zones of the adult rat brain

PubMed Central

Rivera, Patricia; Blanco, Eduardo; Bindila, Laura; Alen, Francisco; Vargas, Antonio; Rubio, Leticia; Pavón, Francisco J.; Serrano, Antonia; Lutz, Beat; Rodríguez de Fonseca, Fernando; Suárez, Juan

2015-01-01

Chronic alcohol exposure reduces endocannabinoid activity and disrupts adult neurogenesis in rodents, which results in structural and functional alterations. Cannabinoid receptor agonists promote adult neural progenitor cell (NPC) proliferation. We evaluated the protective effects of the selective CB1 receptor agonist ACEA, the selective CB2 receptor agonist JWH133 and the fatty-acid amide-hydrolase (FAAH) inhibitor URB597, which enhances endocannabinoid receptor activity, on NPC proliferation in rats with forced consumption of ethanol (10%) or sucrose liquid diets for 2 weeks. We performed immunohistochemical and stereological analyses of cells expressing the mitotic phosphorylation of histone-3 (phospho-H3+) and the replicating cell DNA marker 5-bromo-2'-deoxyuridine (BrdU+) in the main neurogenic zones of adult brain: subgranular zone of dentate gyrus (SGZ), subventricular zone of lateral ventricles (SVZ) and hypothalamus. Animals were allowed ad libitum ethanol intake (7.3 ± 1.1 g/kg/day) after a controlled isocaloric pair-feeding period of sucrose and alcoholic diets. Alcohol intake reduced the number of BrdU+ cells in SGZ, SVZ, and hypothalamus. The treatments (URB597, ACEA, JWH133) exerted a differential increase in alcohol consumption over time, but JWH133 specifically counteracted the deleterious effect of ethanol on NPC proliferation in the SVZ and SGZ, and ACEA reversed this effect in the SGZ only. JWH133 also induced an increased number of BrdU+ cells expressing neuron-specific β3-tubulin in the SVZ and SGZ. These results indicated that the specific activation of CB2 receptors rescued alcohol-induced impaired NPC proliferation, which is a potential clinical interest for the risk of neural damage in alcohol dependence. PMID:26483633

Hematopoietic Stem/Progenitor Cell Proliferation and Differentiation Is Differentially Regulated by High-Density and Low-Density Lipoproteins in Mice

PubMed Central

Feng, Yingmei; Schouteden, Sarah; Geenens, Rachel; Van Duppen, Vik; Herijgers, Paul; Holvoet, Paul; Van Veldhoven, Paul P.; Verfaillie, Catherine M.

2012-01-01

Rationale Hematopoietic stem/progenitor cells (HSPC) are responsible for maintaining the blood system as a result of their self-renewal and multilineage differentiation capacity. Recently, studies have suggested that HDL cholesterol may inhibit and impaired cholesterol efflux may increase HSPC proliferation and differentiation. Objectives We hypothesized that LDL may enhance HSPC proliferation and differentiation while HDL might have the opposing effect which might influence the size of the pool of inflammatory cells. Methods and Results HSPC number and function were studied in hypercholesterolemic LDL receptor knockout (LDLr−/−) mice on high fat diet. Hypercholesterolemia was associated with increased frequency of HSPC, monocytes and granulocytes in the peripheral blood (PB). In addition, an increased proportion of BM HSPC was in G2M of the cell cycle, and the percentage of HSPC and granulocyte-macrophage progenitors (GMP) increased in BM of LDLr−/− mice. When BM Lin-Sca-1+cKit+ (i.e. “LSK”) cells were cultured in the presence of LDL in vitro we also found enhanced differentiation towards monocytes and granulocytes. Furthermore, LDL promoted lineage negative (Lin−) cells motility. The modulation by LDL on HSPC differentiation into granulocytes and motility was inhibited by inhibiting ERK phosphorylation. By contrast, when mice were infused with human apoA-I (the major apolipoprotein of HDL) or reconstituted HDL (rHDL), the frequency and proliferation of HSPC was reduced in BM in vivo. HDL also reversed the LDL-induced monocyte and granulocyte differentiation in vitro. Conclusion Our data suggest that LDL and HDL have opposing effects on HSPC proliferation and differentiation. It will be of interest to determine if breakdown of HSPC homeostasis by hypercholesterolemia contributes to inflammation and atherosclerosis progression. PMID:23144813

Blockade of the SNARE Protein Syntaxin 1 Inhibits Glioblastoma Tumor Growth

PubMed Central

Ulloa, Fausto; Gonzàlez-Juncà, Alba; Meffre, Delphine; Barrecheguren, Pablo José; Martínez-Mármol, Ramón; Pazos, Irene; Olivé, Núria; Cotrufo, Tiziana; Seoane, Joan; Soriano, Eduardo

2015-01-01

Glioblastoma (GBM) is the most prevalent adult brain tumor, with virtually no cure, and with a median overall survival of 15 months from diagnosis despite of the treatment. SNARE proteins mediate membrane fusion events in cells and are essential for many cellular processes including exocytosis and neurotransmission, intracellular trafficking and cell migration. Here we show that the blockade of the SNARE protein Syntaxin 1 (Stx1) function impairs GBM cell proliferation. We show that Stx1 loss-of-function in GBM cells, through ShRNA lentiviral transduction, a Stx1 dominant negative and botulinum toxins, dramatically reduces the growth of GBM after grafting U373 cells into the brain of immune compromised mice. Interestingly, Stx1 role on GBM progression may not be restricted just to cell proliferation since the blockade of Stx1 also reduces in vitro GBM cell invasiveness suggesting a role in several processes relevant for tumor progression. Altogether, our findings indicate that the blockade of SNARE proteins may represent a novel therapeutic tool against GBM. PMID:25803850

Paracrine control of tissue regeneration and cell proliferation by Caspase-3

PubMed Central

Boland, K; Flanagan, L; Prehn, J HM

2013-01-01

Executioner caspases such as Caspase-3 and Caspase-7 have long been recognised as the key proteases involved in cell demolition during apoptosis. Caspase activation also modulates signal transduction inside cells, through activation or inactivation of kinases, phosphatases and other signalling molecules. Interestingly, a series of recent studies have demonstrated that caspase activation may also influence signal transduction and gene expression changes in neighbouring cells that themselves did not activate caspases. This review describes the physiological relevance of paracrine Caspase-3 signalling for developmental processes, tissue homeostasis and tissue regeneration, and discusses the role of soluble factors and microparticles in mediating these paracrine activities. While non-cell autonomous control of tissue regeneration by Caspase-3 may represent an important process for maintaining tissue homeostasis, it may limit the efficiency of current cancer therapy by promoting cell proliferation in those cancer cells resistant to radio- or chemotherapy. We discuss recent evidence in support of such a role for Caspase-3, and discuss its therapeutic implication. PMID:23846227

Leucine Metabolism in T Cell Activation: mTOR Signaling and Beyond123

PubMed Central

Powell, Jonathan D; Hutson, Susan M

2016-01-01

In connection with the increasing interest in metabolic regulation of the immune response, this review discusses current advances in understanding the role of leucine and leucine metabolism in T lymphocyte (T cell) activation. T cell activation during the development of an immune response depends on metabolic reprogramming to ensure that sufficient nutrients and energy are taken up by the highly proliferating T cells. Leucine has been described as an important essential amino acid and a nutrient signal that activates complex 1 of the mammalian target of rapamycin (mTORC1), which is a critical regulator of T cell proliferation, differentiation, and function. The role of leucine in these processes is further discussed in relation to amino acid transporters, leucine-degrading enzymes, and other metabolites of leucine metabolism. A new model of T cell regulation by leucine is proposed and outlines a chain of events that leads to the activation of mTORC1 in T cells. PMID:27422517

Rac1 Guides Porf-2 to Wnt Pathway to Mediate Neural Stem Cell Proliferation

PubMed Central

Yang, Xi-Tao; Huang, Guo-Hui; Li, Hong-Jiang; Sun, Zhao-Liang; Xu, Nan-Jie; Feng, Dong-Fu

2017-01-01

The molecular and cellular mechanisms underlying the anti-proliferative effects of preoptic regulator factor 2 (Porf-2) on neural stem cells (NSCs) remain largely unknown. Here, we found that Porf-2 inhibits the activity of ras-related C3 botulinum toxin substrate 1 (Rac1) protein in hippocampus-derived rat NSCs. Reduced Rac1 activity impaired the nuclear translocation of β-catenin, ultimately causing a repression of NSCs proliferation. Porf-2 knockdown enhanced NSCs proliferation but not in the presence of small molecule inhibitors of Rac1 or Wnt. At the same time, the repression of NSCs proliferation caused by Porf-2 overexpression was counteracted by small molecule activators of Rac1 or Wnt. By using a rat optic nerve crush model, we observed that Porf-2 knockdown enhanced the recovery of visual function. In particular, optic nerve injury in rats led to increased Wnt family member 3a (Wnt3a) protein expression, which we found responsible for enhancing Porf-2 knockdown-induced NSCs proliferation. These findings suggest that Porf-2 exerts its inhibitory effect on NSCs proliferation via Rac1-Wnt/β-catenin pathway. Porf-2 may therefore represent and interesting target for optic nerve injury recovery and therapy. PMID:28626389

Regional-specific effect of fluoxetine on rapidly dividing progenitors along the dorsoventral axis of the hippocampus.

PubMed

Zhou, Qi-Gang; Lee, Daehoon; Ro, Eun Jeoung; Suh, Hoonkyo

2016-10-19

Hippocampus-dependent cognitive and emotional function appears to be regionally dissociated along the dorsoventral (DV) axis of the hippocampus. Recent observations that adult hippocampal neurogenesis plays a critical role in both cognition and emotion raised an interesting question whether adult neurogenesis within specific subregions of the hippocampus contributes to these distinct functions. We examined the regional-specific and cell type-specific effects of fluoxetine, which requires adult hippocampal neurogenesis to function as an antidepressant, on the proliferation of hippocampal neural stem cells (NSCs). Fluoxetine specifically increased proliferation of NSCs located in the ventral region of the hippocampus while the mitotic index of NSCs in the dorsal portion of the hippocampus remained unaltered. Moreover, within the ventral hippocampus, type II NSC and neuroblast populations specifically responded to fluoxetine, showing increased proliferation; however, proliferation of type I NSCs was unchanged in response to fluoxetine. Activation or inhibition of serotonin receptor 1A (5-HTR1A) recapitulated or abolished the effect of fluoxetine on proliferation of type II NSCs and neuroblast populations in the ventral hippocampus. Our study showed that the effect of fluoxetine on proliferation is dependent upon the type and the position of the NSCs along the DV axis of the hippocampus.

Altered Hepa1-6 cells by dimethyl sulfoxide (DMSO)-treatment induce anti-tumor immunity in vivo.

PubMed

Jiang, Zhengyu; Zhang, Hongxia; Wang, Ye; Yu, Bin; Wang, Chen; Liu, Changcheng; Lu, Juan; Chen, Fei; Wang, Minjun; Yu, Xinlu; Lin, Jiahao; Pan, Xinghua; Wang, Pin; Zhu, Haiying

2016-02-23

Cancer immunotherapy is the use of the immune system to treat cancer. Our current research proposed an optional strategy of activating immune system involving in cancer immunotherapy. When being treated with 2% DMSO in culture medium, Hepa1-6 cells showed depressed proliferation with no significant apoptosis or decreased viability. D-hep cells, Hepa1-6 cells treated with DMSO for 7 days, could restore to the higher proliferation rate in DMSO-free medium, but alteration of gene expression profile was irreversible. Interestingly, tumors from D-hep cells, not Hepa1-6 cells, regressed in wild-type C57BL/6 mice whereas D-hep cells exhibited similar tumorigenesis as Hep1-6 cells in immunodeficient mice. As expected, additional Hepa1-6 cells failed to form tumors in the D-hep-C57 mice in which D-hep cells were eliminated. Further research confirmed that D-hep-C57 mice established anti-tumor immunity against Hepa1-6 cells. Our research proposed viable tumor cells with altered biological features by DMSO-treatment could induce anti-tumor immunity in vivo.

Shock Waves for Possible Application in Regenerative Medicine

NASA Astrophysics Data System (ADS)

Hosseini, S. H. R.; Nejad, S. Moosavi; Akiyama, H.

The paper reports experimental study of underwater shock waves effects in modification and possible control of embryonic stem cell differentiation and proliferation. The study is motivated by its application in regenerativemedicine. Underwater shock waves have been of interest for various scientific, industrial, and medical applications.

Up-regulation of tumor suppressor carcinoembryonic antigen-related cell adhesion molecule 1 in human colon cancer Caco-2 cells following repetitive exposure to dietary levels of a polyphenol-rich chokeberry juice.

PubMed

Bermúdez-Soto, María J; Larrosa, Mar; Garcia-Cantalejo, Jesús M; Espín, Juan C; Tomás-Barberan, Francisco A; García-Conesa, María T

2007-04-01

Consumption of berries and red fruits rich in polyphenols may contribute to the reduction of colon cancer through mechanisms not yet understood. In this study, we investigated the response of subconfluent Caco-2 cells (a human colon carcinoma model) to repetitive exposure (2 h a day for a 4-day period) of a subtoxic dose of a chokeberry (Aronia melanocarpa) juice containing mixed polyphenols. To mimic physiological conditions, we subjected the chokeberry juice to in vitro gastric and pancreatic digestion. The effects on viability, proliferation and cell cycle were determined, and changes in the expression of genes in response to the chokeberry treatment were screened using Affymetrix oligonucleotide microarrays. Exposure to the chokeberry juice inhibited Caco-2 cell proliferation by causing G(2)/M cell cycle arrest. We detected changes in the expression of a group of genes involved in cell growth and proliferation and cell cycle regulation, as well as those associated to colorectal cancer. A selection of these genes was further confirmed by quantitative RT-PCR. Among these, the tumor suppressor carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1), whose expression is known to be reduced in the majority of early adenomas and carcinomas, was up-regulated by the treatment both at the mRNA and protein levels (as shown by flow cytometry analysis). CEACAM1, with a significant regulatory role on cell proliferation of particular interest at early stages of cancer development, may be a potential target for chemoprevention by food components such as those present in polyphenol-rich fruits.

Constituents of Mediterranean Spices Counteracting Vascular Smooth Muscle Cell Proliferation: Identification and Characterization of Rosmarinic Acid Methyl Ester as a Novel Inhibitor.

PubMed

Liu, Rongxia; Heiss, Elke H; Waltenberger, Birgit; Blažević, Tina; Schachner, Daniel; Jiang, Baohong; Krystof, Vladimir; Liu, Wanhui; Schwaiger, Stefan; Peña-Rodríguez, Luis M; Breuss, Johannes M; Stuppner, Hermann; Dirsch, Verena M; Atanasov, Atanas G

2018-04-01

Aberrant vascular smooth muscle cell (VSMC) proliferation is involved in atherosclerotic plaque formation and restenosis. Mediterranean spices have been reported to confer cardioprotection, but their direct influence on VSMCs has largely not been investigated. This study aims at examining rosmarinic acid (RA) and 11 related constituents for inhibition of VSMC proliferation in vitro, and at characterizing the most promising compound for their mode of action and influence on neointima formation in vivo. RA, rosmarinic acid methyl ester (RAME), and caffeic acid methyl ester inhibit VSMC proliferation in a resazurin conversion assay with IC 50 s of 5.79, 3.12, and 6.78 µm, respectively. RAME significantly reduced neointima formation in vivo in a mouse femoral artery cuff model. Accordingly, RAME leads to an accumulation of VSMCs in the G 0 /G 1 cell-cycle phase, as indicated by blunted retinoblastoma protein phosphorylation upon mitogen stimulation and inhibition of cyclin-dependent kinase 2 in vitro. RAME represses PDGF-induced VSMC proliferation in vitro and reduces neointima formation in vivo. These results recommend RAME as an interesting compound with VSMC-inhibiting potential. Future metabolism and pharmacokinetics studies might help to further evaluate the potential relevance of RAME and other spice-derived polyphenolics for vasoprotection. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

c-Myc inhibits myoblast differentiation and promotes myoblast proliferation and muscle fibre hypertrophy by regulating the expression of its target genes, miRNAs and lincRNAs.

PubMed

Luo, Wen; Chen, Jiahui; Li, Limin; Ren, Xueyi; Cheng, Tian; Lu, Shiyi; Lawal, Raman Akinyanju; Nie, Qinghua; Zhang, Xiquan; Hanotte, Olivier

2018-05-21

The transcription factor c-Myc is an important regulator of cellular proliferation, differentiation and embryogenesis. While c-Myc can inhibit myoblast differentiation, the underlying mechanisms remain poorly understood. Here, we found that c-Myc does not only inhibits myoblast differentiation but also promotes myoblast proliferation and muscle fibre hypertrophy. By performing chromatin immunoprecipitation and high-throughput sequencing (ChIP-seq), we identified the genome-wide binding profile of c-Myc in skeletal muscle cells. c-Myc achieves its regulatory effects on myoblast proliferation and differentiation by targeting the cell cycle pathway. Additionally, c-Myc can regulate cell cycle genes by controlling miRNA expression of which dozens of miRNAs can also be regulated directly by c-Myc. Among these c-Myc-associated miRNAs (CAMs), the roles played by c-Myc-induced miRNAs in skeletal muscle cells are similar to those played by c-Myc, whereas c-Myc-repressed miRNAs play roles that are opposite to those played by c-Myc. The cell cycle, ERK-MAPK and Akt-mediated pathways are potential target pathways of the CAMs during myoblast differentiation. Interestingly, we identified four CAMs that can directly bind to the c-Myc 3' UTR and inhibit c-Myc expression, suggesting that a negative feedback loop exists between c-Myc and its target miRNAs during myoblast differentiation. c-Myc also potentially regulates many long intergenic noncoding RNAs (lincRNAs). Linc-2949 and linc-1369 are directly regulated by c-Myc, and both lincRNAs are involved in the regulation of myoblast proliferation and differentiation by competing for the binding of muscle differentiation-related miRNAs. Our findings do not only provide a genome-wide overview of the role the c-Myc plays in skeletal muscle cells but also uncover the mechanism of how c-Myc and its target genes regulate myoblast proliferation and differentiation, and muscle fibre hypertrophy.

The bruton tyrosine kinase inhibitor ibrutinib (PCI-32765) blocks hairy cell leukaemia survival, proliferation and B cell receptor signalling: a new therapeutic approach.

PubMed

Sivina, Mariela; Kreitman, Robert J; Arons, Evgeny; Ravandi, Farhad; Burger, Jan A

2014-07-01

B cell receptor (BCR) signalling plays a critical role in the progression of several B-cell malignancies, but its role in hairy cell leukaemia (HCL) is ambiguous. Bruton tyrosine kinase (BTK), a key player in BCR signalling, as well as B cell migration and adhesion, can be targeted with ibrutinib, a selective, irreversible BTK inhibitor. We analysed BTK expression and function in HCL and analysed the effects of ibrutinib on HCL cells. We demonstrated uniform BTK protein expression in HCL cells. Ibrutinib significantly inhibited HCL proliferation and cell cycle progression. Accordingly, ibrutinib also reduced HCL cell survival after BCR triggering with anti-immunoglobulins and abrogated the activation of kinases downstream of the BCR (PI3K and MAPK). Ibrutinib also inhibited BCR-dependent secretion of the chemokines CCL3 and CCL4 by HCL cells. Interestingly, ibrutinib inhibited also CXCL12-induced signalling, a key pathway for bone marrow homing. Collectively, our data support the clinical development of ibrutinib in patients with HCL. © 2014 John Wiley & Sons Ltd.

Immune Regulatory Properties of CD117pos Amniotic Fluid Stem Cells Vary According to Gestational Age

PubMed Central

Di Trapani, Mariano; Bassi, Giulio; Fontana, Emanuela; Giacomello, Luca; Pozzobon, Michela; Guillot, Pascale V.; De Coppi, Paolo

2015-01-01

Amniotic Fluid Stem (AFS) cells are broadly multipotent fetal stem cells derived from the positive selection and ex vivo expansion of amniotic fluid CD117/c-kitpos cells. Considering the differentiation potential in vitro toward cell lineages belonging to the three germ layers, AFS cells have raised great interest as a new therapeutic tool, but their immune properties still need to be assessed. We analyzed the in vitro immunological properties of AFS cells from different gestational age in coculture with T, B, and natural killer (NK) cells. Nonactivated (resting) first trimester-AFS cells showed lower expression of HLA class-I molecules and NK-activating ligands than second and third trimester-AFS cells, whose features were associated with lower sensitivity to NK cell-mediated lysis. Nevertheless, inflammatory priming with interferon gamma (IFN-γ) and tumor necrosis factor alpha (TNF-α) enhanced resistance of all AFS cell types to NK cytotoxicity. AFS cells modulated lymphocyte proliferation in a different manner according to gestational age: first trimester-AFS cells significantly inhibited T and NK cell proliferation, while second and third trimester-AFS cells were less efficient. In addition, only inflammatory-primed second trimester-AFS cells could suppress B cell proliferation, which was not affected by the first and third trimester-AFS cells. Indolamine 2,3 dioxygenase pathway was significantly involved only in T cell suppression mediated by second and third trimester-AFS cells. Overall, this study shows a number of significant quantitative differences among AFS cells of different gestational age that have to be considered in view of their clinical application. PMID:25072397

Involvement of glutathione/glutathione S-transferase antioxidant system in butyrate-inhibited vascular smooth muscle cell proliferation.

PubMed

Ranganna, Kasturi; Mathew, Omana P; Yatsu, Frank M; Yousefipour, Zivar; Hayes, Barbara E; Milton, Shirlette G

2007-11-01

Vascular smooth muscle cell (VSMC) proliferation is an important etiological factor in vascular proliferative diseases such as primary atherosclerosis, hypertension, arterial and in-stent restenosis, and transplant vasculopathy. Our studies established that butyrate, a bacterial fermentation product of dietary fiber and a chromatin modulator, is a potent inhibitor of VSMC proliferation. The cardiovascular health benefits of a high-fiber diet, the principle source of butyrate in the body, have been known for a long time, however, very little is known about the antiatherogenic potential of butyrate. Because oxidative stress plays an important role in the pathogenesis of atherosclerosis, we examined involvement of the glutathione/glutathione S-transferase (GST) antioxidant system in butyrate's inhibition of VSMC proliferation. Treatment of proliferating VSMCs with butyrate leads to the induction of several GSTs. Interestingly, our study also demonstrated the nuclear localization of GST-P1 (GST-7-7), which is considered to be a cytosolic protein; this was demonstrated using immunostaining and was corroborated by western blotting. Also, the butyrate-induced antiproliferative action, and the induction of GST-P1 and its nuclear localization are downregulated when butyrate is withdrawn. Furthermore, assessment of intracellular glutathione levels reveals their augmentation by butyrate. Conversely, butyrate treatment reduces the levels of reactive oxygen species in VSMCs. Collectively, the butyrate-treatment-related increase in glutathione content, the reduction in reactive oxygen species, the upregulation of GST and the nuclear localization of GST-P1 in growth-arrested VSMCs imply that butyrate's antiproliferative action involves modulation of the cellular redox state. Thus, induction of the glutathione/GST antioxidant system appears to have other regulatory role(s) besides detoxification and regulation of the cellular redox state, for example, cell-cycle control and cell proliferation, which are both critical to atherogenesis.

Site-Specific Phosphorylation of Ikaros Induced by Low-Dose Ionizing Radiation Regulates Cell Cycle Progression of B Lymphoblast Through CK2 and AKT Activation.

PubMed

Cho, Seong-Jun; Kang, Hana; Kim, Min Young; Lee, Jung Eun; Kim, Sung Jin; Nam, Seon Young; Kim, Ji Young; Kim, Hee Sun; Pyo, Suhkneung; Yang, Kwang Hee

2016-04-01

To determine how low-dose ionizing radiation (LDIR) regulates B lympho-proliferation and its molecular mechanism related with Ikaros, transcription factor. Splenocytes and IM-9 cells were uniformly irradiated with various doses of a (137)Cs γ-source, and cell proliferation was analyzed. To determine the LDIR-specific phosphorylation of Ikaros, immunoprecipitation and Western blot analysis were performed. To investigate the physiologic function of LDIR-mediatied Ikaros phosphorylation, Ikaros mutants at phosphorylation sites were generated, and cell cycle analysis was performed. First, we found that LDIR enhances B lymphoblast proliferation in an Ikaros-dependent manner. Moreover, we found that LDIR elevates the phosphorylation level of Ikaros protein. Interestingly, we showed that CK2 and AKT are involved in LDIR-induced Ikaros phosphorylation and capable of regulating DNA binding activity of Ikaros via specific phosphorylation. Finally, we identified LDIR-specific Ikaros phosphorylation sites at S391/S393 and showed that the Ikaros phosphorylations at these sites control Ikaros's ability to regulate G1/S cell cycle progression. Low-dose ionizing radiation specifically phosphorylates Ikaros protein at Ser 391/393 residues to regulate cell cycle progression in B lymphoblast. Copyright © 2016 Elsevier Inc. All rights reserved.

The effect of gestational diabetes on proliferation capacity and viability of human umbilical cord-derived stromal cells.

PubMed

Wajid, Nadia; Naseem, Rashida; Anwar, Sanam Saiqa; Awan, Sana Javaid; Ali, Muhammad; Javed, Sara; Ali, Fatima

2015-09-01

Stomal cells derived from Wharton's jelly of human umbilical cord (WJMSCs) are considered as the potential therapeutic agents for regeneration and are getting famous for stem cell banking. Our study aims to evaluate the effects of gestational diabetes on proliferation capacity and viability of WJMSCs. Mesenchymal stromal cells were isolated from Wharton's jelly of human umbilical cords from normal and gestational diabetic (DWJMSCs) mothers. Growth patterns of both types of cells were analyzed through MTT assay and population doubling time. Cell survival, cell death and glucose utilization were estimated through trypan blue exclusion assay, LDH assay and glucose detection assay respectively. Angiogenic ability was evaluated by immunocytochemistry and ELISA for VEGF A. Anti-cancerous potential was analyzed on HeLa cells. DWJMSCs exhibited low proliferative rate, increased population doubling time, reduced cell viability and increased cell death. Interestingly, DWJMSCs were found to have a reduced glucose utilization and anti-cancerous ability while enhanced angiogenic ability. Gestational diabetes induces adverse effects on growth, angiogenic and anti-cancerous potential of WJMSCs.

Circadian clock regulation of the cell cycle in the zebrafish intestine.

PubMed

Peyric, Elodie; Moore, Helen A; Whitmore, David

2013-01-01

The circadian clock controls cell proliferation in a number of healthy tissues where cell renewal and regeneration are critical for normal physiological function. The intestine is an organ that typically undergoes regular cycles of cell division, differentiation and apoptosis as part of its role in digestion and nutrient absorption. The aim of this study was to explore circadian clock regulation of cell proliferation and cell cycle gene expression in the zebrafish intestine. Here we show that the zebrafish gut contains a directly light-entrainable circadian pacemaker, which regulates the daily timing of mitosis. Furthermore, this intestinal clock controls the expression of key cell cycle regulators, such as cdc2, wee1, p21, PCNA and cdk2, but only weakly influences cyclin B1, cyclin B2 and cyclin E1 expression. Interestingly, food deprivation has little impact on circadian clock function in the gut, but dramatically reduces cell proliferation, as well as cell cycle gene expression in this tissue. Timed feeding under constant dark conditions is able to drive rhythmic expression not only of circadian clock genes, but also of several cell cycle genes, suggesting that food can entrain the clock, as well as the cell cycle in the intestine. Rather surprisingly, we found that timed feeding is critical for high amplitude rhythms in cell cycle gene expression, even when zebrafish are maintained on a light-dark cycle. Together these results suggest that the intestinal clock integrates multiple rhythmic cues, including light and food, to function optimally.

Circadian Clock Regulation of the Cell Cycle in the Zebrafish Intestine

PubMed Central

Peyric, Elodie; Moore, Helen A.; Whitmore, David

2013-01-01

The circadian clock controls cell proliferation in a number of healthy tissues where cell renewal and regeneration are critical for normal physiological function. The intestine is an organ that typically undergoes regular cycles of cell division, differentiation and apoptosis as part of its role in digestion and nutrient absorption. The aim of this study was to explore circadian clock regulation of cell proliferation and cell cycle gene expression in the zebrafish intestine. Here we show that the zebrafish gut contains a directly light-entrainable circadian pacemaker, which regulates the daily timing of mitosis. Furthermore, this intestinal clock controls the expression of key cell cycle regulators, such as cdc2, wee1, p21, PCNA and cdk2, but only weakly influences cyclin B1, cyclin B2 and cyclin E1 expression. Interestingly, food deprivation has little impact on circadian clock function in the gut, but dramatically reduces cell proliferation, as well as cell cycle gene expression in this tissue. Timed feeding under constant dark conditions is able to drive rhythmic expression not only of circadian clock genes, but also of several cell cycle genes, suggesting that food can entrain the clock, as well as the cell cycle in the intestine. Rather surprisingly, we found that timed feeding is critical for high amplitude rhythms in cell cycle gene expression, even when zebrafish are maintained on a light-dark cycle. Together these results suggest that the intestinal clock integrates multiple rhythmic cues, including light and food, to function optimally. PMID:24013905

Cannabidiol Activates Neuronal Precursor Genes in Human Gingival Mesenchymal Stromal Cells.

PubMed

Soundara Rajan, Thangavelu; Giacoppo, Sabrina; Scionti, Domenico; Diomede, Francesca; Grassi, Gianpaolo; Pollastro, Federica; Piattelli, Adriano; Bramanti, Placido; Mazzon, Emanuela; Trubiani, Oriana

2017-06-01

In the last years, mesenchymal stromal cells (MSCs) from oral tissues have received considerable interest in regenerative medicine since they can be obtained with minimal invasive procedure and exhibit immunomodulatory properties. This study was aimed to investigate whether in vitro pre-treatment of MSCs obtained from human gingiva (hGMSCs) with Cannabidiol (CBD), a cannabinoid component produced by the plant Cannabis sativa, may promote human gingiva derived MSCs to differentiate toward neuronal precursor cells. Specifically, we have treated the hGMSCs with CBD (5 µM) for 24 h in order to evaluate the expression of genes involved in cannabidiol signaling, cell proliferation, self-renewal and multipotency, and neural progenitor cells differentiation. Next generation sequencing (NGS) demonstrated that CBD activates genes associated with G protein coupled receptor signaling in hGMSCs. Genes involved in DNA replication, cell cycle, proliferation, and apoptosis were regulated. Moreover, genes associated with the biological process of neuronal progenitor cells (NCPs) proliferation, neuron differentiation, neurogenesis, and nervous system development were significantly modulated. From our results, we hypothesize that human gingiva-derived MSCs conditioned with CBD could represent a valid method for improving the hGMSCs phenotype and thus might be a potential therapeutic tool in the treatment of neurodegenerative diseases. J. Cell. Biochem. 118: 1531-1546, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Mequindox induced cellular DNA damage via generation of reactive oxygen species.

PubMed

Liu, Jing; Ouyang, Man; Jiang, Jun; Mu, Peiqiang; Wu, Jun; Yang, Qi; Zhang, Caihui; Xu, Weiying; Wang, Lijuan; Huen, Michael S Y; Deng, Yiqun

2012-01-24

Mequindox, a quinoxaline-N-dioxide derivative that possesses antibacterial properties, has been widely used as a feed additive in the stockbreeding industry in China. While recent pharmacological studies have uncovered potential hazardous effects of mequindox, exactly how mequindox induces pathological changes and the cellular responses associated with its consumption remain largely unexplored. In this study, we investigated the cellular responses associated with mequindox treatment. We report here that mequindox inhibits cell proliferation by arresting cells at the G2/M phase of the cell cycle. Interestingly, this mequindox-associated deleterious effect on cell proliferation was observed in human, pig as well as chicken cells, suggesting that mequindox acts on evolutionarily conserved target(s). To further understand the mequindox-host interaction and the mechanism underlying mequindox-induced cell cycle arrest, we measured the cellular content of DNA damage, which is known to perturb cell proliferation and compromise cell survival. Accordingly, using γ-H2AX as a surrogate marker for DNA damage, we found that mequindox treatment induced cellular DNA damage, which paralleled the chemical-induced elevation of reactive oxygen species (ROS) levels. Importantly, expression of the antioxidant enzyme catalase partially alleviated these mequindox-associated effects. Taken together, our results suggest that mequindox cytotoxicity is attributable, in part, to its role as a potent inducer of DNA damage via ROS. © 2011 Elsevier B.V. All rights reserved.

Metformin selectively affects human glioblastoma tumor-initiating cell viability

PubMed Central

Würth, Roberto; Pattarozzi, Alessandra; Gatti, Monica; Bajetto, Adirana; Corsaro, Alessandro; Parodi, Alessia; Sirito, Rodolfo; Massollo, Michela; Marini, Cecilia; Zona, Gianluigi; Fenoglio, Daniela; Sambuceti, Gianmario; Filaci, Gilberto; Daga, Antonio; Barbieri, Federica; Florio, Tullio

2013-01-01

Cancer stem cell theory postulates that a small population of tumor-initiating cells is responsible for the development, progression and recurrence of several malignancies, including glioblastoma. In this perspective, tumor-initiating cells represent the most relevant target to obtain effective cancer treatment. Metformin, a first-line drug for type II diabetes, was reported to possess anticancer properties affecting the survival of cancer stem cells in breast cancer models. We report that metformin treatment reduced the proliferation rate of tumor-initiating cell-enriched cultures isolated from four human glioblastomas. Metformin also impairs tumor-initiating cell spherogenesis, indicating a direct effect on self-renewal mechanisms. Interestingly, analyzing by FACS the antiproliferative effects of metformin on CD133-expressing subpopulation, a component of glioblastoma cancer stem cells, a higher reduction of proliferation was observed as compared with CD133-negative cells, suggesting a certain degree of cancer stem cell selectivity in its effects. In fact, glioblastoma cell differentiation strongly reduced sensitivity to metformin treatment. Metformin effects in tumor-initiating cell-enriched cultures were associated with a powerful inhibition of Akt-dependent cell survival pathway, while this pathway was not affected in differentiated cells. The specificity of metformin antiproliferative effects toward glioblastoma tumor-initiating cells was confirmed by the lack of significant inhibition of normal human stem cells (umbilical cord-derived mesenchymal stem cells) in vitro proliferation after metformin exposure. Altogether, these data clearly suggest that metformin exerts antiproliferative activity on glioblastoma cells, showing a higher specificity toward tumor-initiating cells, and that the inhibition of Akt pathway may represent a possible intracellular target of this effect. PMID:23255107

Systemic application of sirolimus prevents neointima formation not via a direct anti-proliferative effect but via its anti-inflammatory properties.

PubMed

Daniel, Jan-Marcus; Dutzmann, Jochen; Brunsch, Hannes; Bauersachs, Johann; Braun-Dullaeus, Rüdiger; Sedding, Daniel G

2017-07-01

Systemic treatment with sirolimus, as used for immunosuppression in transplant patients, results in markedly low rates of in-stent restenosis. Since the underlying mechanisms remain obscure, we aimed to determine the molecular and cellular effects of systemic sirolimus treatment on vascular remodeling processes. Systemic sirolimus treatment significantly reduced smooth muscle cell (SMC) proliferation 14days after wire-induced injury and neointima formation 28days after injury in C57BL/6 mice, while simultaneously impairing re-endothelialization. Interestingly, in vitro, sirolimus had no direct effect on the proliferation of SMC or endothelial cells (EC) at serum concentrations observed after systemic application. In contrast, sirolimus reduced the adhesion of leukocytes (CD45 + ) and bone marrow-derived progenitor cells (CD34 + ) to activated EC by down-regulating the adhesion molecules ICAM-1 and VCAM-1. In addition, sirolimus treatment also significantly reduced the upregulation of ICAM-1 and VCAM-1 and the recruitment of monocytic cells (MOMA-2 + ) in neointimal lesions in vivo. Our findings show that systemic sirolimus treatment effectively prevents SMC and EC proliferation in vivo without directly affecting these cells. Instead, sirolimus prevents neointima formation and re-endothelialization by attenuating the inflammatory response after injury with secondary effects on SMC and EC proliferation. Thus, despite a similar net effect, the mechanisms of systemic sirolimus treatment are largely different from the local effects achieved after application of sirolimus-eluting stents. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

[The role of cellular senescence in carcinogenesis and antitumor therapy].

PubMed

Mosieniak, Grazyna; Strzeszewska, Anna

2014-01-01

Cellular senescence is the process that lead to terminal growth arrest induced by unrepairable double strand DNA damage (DSB). Moreover, activation of the oncogenes as well as inhibition of the tumor suppressor genes were shown to contribute to senescence induction and the senescent cells were identified in the premalignant lesions. Thus senescence is considered as an natural antitumor barrier that act at the early stages of cancerogenesis to stop the proliferation of transformed cells. Interestingly, the premalignant cells that escaped senescence and progress into full blown tumor cells still remain sensitive to induction of senescence, for example during chemio- or radiotherapy. Thus, induction of cancer cell senescence, similarly to apoptosis, is considered to restrain tumor growth and thus contribute to effectiveness of anticancer therapy. The senescent cells, although do not proliferate, remain viable and metabolically active. They secret a lot of cytokines, mitogens as well as enzymes degrading extracellular matrix. These factors can have opposing effect on neighboring cells, leading to senescence induction or stimulation of proliferation. Thus, senescence can act as an double edge sword that inhibit the propagation of potentially dangerous, transformed cells on one hand or induce cell division of the same cell on the other. Presently a lot of work is focused on finding new therapeutic strategies that would involve the tumor targeted senescence induction in both early late stages of cancer development. Nevertheless, the unwanted influence of the senescent cells on the microenvironment, requires careful monitoring the effects of pro-senescent therapies in each case.

Impact of Lactic Acid on Cell Proliferation and Free Radical Induced Cell Death in Monolayer Cultures of Neural Precursor Cells

PubMed Central

Lampe, Kyle J.; Namba, Rachael M.; Silverman, Tyler R.; Bjugstad, Kimberly B.

2009-01-01

Biomaterials prepared from polyesters of lactic acid and glycolic acid, or a mixture of the two, degrade in the presence of water into the naturally occurring metabolites, lactic acid and glycolic acid. While the lactic acid degradation product that is released from biomaterials is well-tolerated by the body, lactic acid can influence the metabolic function of cells; it can serve as an energy substrate for cells, and has been shown to have antioxidant properties. Neural precursor cells, a cell population of considerable interest as a source of cells for neural tissue regeneration strategies, generate a high amount of reactive oxygen species, and when associated with a degradable biomaterial, may be impacted by released lactic acid. In this work, the effect of lactic acid on a neural cell population containing proliferative neural precursor cells was examined in monolayer culture. Lactic acid was found to scavenge exogenously added free radicals produced in the presence of either hydrogen peroxide or a photoinitiator (I2959) commonly utilized in the preparation of photopolymerizable biomaterials. In addition to its effect on exogenously added free radicals, lactic acid reduced intracellular redox state, increased the proliferation of the cell population, and modified the cell composition. The findings of this study provide insight into the role that lactic acid plays naturally on developing neural cells and are also of interest to biomaterials scientists that are focused on the development of degradable lactic-acid based polymers for cell culture devices. The effect of lactic acid on other cell populations may differ and should be characterized to best understand how cells function in degradable cell culture devices. PMID:19408314

Response of human bone marrow-derived MSCs on triphasic Ca-P substrate with various HA/TCP ratio.

PubMed

Bajpai, Indu; Kim, Duk Yeon; Kyong-Jin, Jung; Song, In-Hwan; Kim, Sukyoung

2017-01-01

Calcium phosphates (Ca-P) are used commonly as artificial bone substitutes to control the biodegradation rate of an implant in the body fluid. This study examined the in vitro proliferation of human bone marrow-derived mesenchymal stem cells (hBMSCs) on triphasic Ca-P samples. For this aspect, hydroxyapatite (HA), dicalcium phosphate dehydrate (DCPD), and calcium hydroxide (Ca(OH) 2 ) were mixed at various ratios, cold compacted, and sintered at 1250°C in air. X-ray diffraction showed that the β-tricalcium phosphate (TCP) to α-TCP phase transformation increased with increasing DCPD/HA ratio. The micro-hardness deceased with increasing TCP content, whereas the mean grain size and porosity increased with increasing TCP concentration. To evaluate the in vitro degree of adhesion and proliferation on the HA/TCP samples, human BMSCs were incubated on the HA/TCP samples and analyzed by a cells proliferation assay, expression of the extracellular matrix (ECM) genes, such as α-smooth muscle actin (α-SMA) and fibronectin (FN), and FITC-phalloidin fluorescent staining. In terms of the interactions of human BMSCs with the triphasic Ca-P samples, H50T50 (Ca/P = 1.59) markedly enhanced cell spreading, proliferation, FN, and α-SMA compared with H100T0 (Ca/P = 1.67). Interestingly, these results show that among the five HA/TCP samples, H50T50 is the optimal Ca-P composition for in vitro cell proliferation. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 72-80, 2017. © 2015 Wiley Periodicals, Inc.

Antitumor and angiostatic peptides from frog skin secretions.

PubMed

van Zoggel, Hanneke; Hamma-Kourbali, Yamina; Galanth, Cécile; Ladram, Ali; Nicolas, Pierre; Courty, José; Amiche, Mohamed; Delbé, Jean

2012-01-01

The discovery of new molecules with potential antitumor activity continues to be of great importance in cancer research. In this respect, natural antimicrobial peptides isolated from various animal species including humans and amphibians have been found to be of particular interest. Here, we report the presence of two anti-proliferative peptides active against cancer cells in the skin secretions of the South American tree frog, Phyllomedusa bicolor. The crude skin exudate was fractioned by size exclusion gel followed by reverse-phase HPLC chromatography. After these two purification steps, we identified two fractions that exhibited anti-proliferative activity. Sequence analysis indicated that this activity was due to two antimicrobial α-helical cationic peptides of the dermaseptin family (dermaseptins B2 and B3). This result was confirmed using synthetic dermaseptins. When tested in vitro, synthetic B2 and B3 dermaseptins inhibited the proliferation of the human prostatic adenocarcinoma PC-3 cell line by more than 90%, with an EC(50) of around 2-3 μM. No effect was observed on the growth of the NIH-3T3 non-tumor mouse cell line with Drs B2, whereas a slight inhibiting effect was observed with Drs B3 at high dose. In addition, the two fractions obtained after size exclusion chromatography also inhibited PC-3 cell colony formation in soft agar. Interestingly, inhibition of the proliferation and differentiation of activated adult bovine aortic endothelial cells was observed in cells treated with these two fractions. Dermaseptins B2 and B3 could, therefore, represent interesting new pharmacological molecules with antitumor and angiostatic properties for the development of a new class of anticancer drugs.

Biciliated ependymal cell proliferation contributes to spinal cord growth

PubMed Central

Alfaro-Cervello, Clara; Soriano-Navarro, Mario; Mirzadeh, Zaman; Alvarez-Buylla, Arturo; Garcia-Verdugo, Jose Manuel

2013-01-01

Two neurogenic regions have been described in the adult brain, the lateral ventricle subventricular zone and the dentate gyrus subgranular zone. It has been suggested that neural stem cells also line the central canal of the adult spinal cord. Using transmission and scanning electron microscopy and immunostaining, we describe here the organization and cell types of the central canal epithelium in adult mice. The identity of dividing cells was determined by three-dimensional ultrastructural reconstructions of [3H]thymidine-labeled cells and confocal analysis of bromodeoxyuridine labeling. The most common cell type lining the central canal had two long motile (9+2) cilia and was vimentin+, CD24+, FoxJ1+, Sox2+ and CD133+, but nestin- and glial fibrillary acidic protein (GFAP)-. These biciliated ependymal cells of the central canal (Ecc) resembled E2 cells of the lateral ventricles, but their basal bodies were different from that of E2 or E1 cells. Interestingly, we frequently found Ecc cells with two nuclei and four cilia, suggesting they are formed by incomplete cytokinesis or cell fusion. GFAP+ astrocytes with a single cilium and an orthogonally oriented centriole were also observed. The majority of dividing cells corresponded to biciliated Ecc cells. Central canal proliferation was most common during the active period of spinal cord growth. Pairs of labeled Ecc cells were observed within the central canal in adult mice 2.5 weeks post-labeling. Our work suggests that the vast majority of postnatal dividing cells in the central canal are Ecc cells and their proliferation is associated with the growth of the spinal cord. PMID:22434575

Deletion of eIF2β lysine stretches creates a dominant negative that affects the translation and proliferation in human cell line: A tool for arresting the cell growth.

PubMed

Salton, Gabrielle Dias; Laurino, Claudia Cilene Fernandes Correia; Mega, Nicolás Oliveira; Delgado-Cañedo, Andrés; Setterblad, Niclas; Carmagnat, Maryvonnick; Xavier, Ricardo Machado; Cirne-Lima, Elizabeth; Lenz, Guido; Henriques, João Antonio Pêgas; Laurino, Jomar Pereira

2017-08-03

Eukaryote initiation factor 2 subunit β (eIF2β) plays a crucial role in regulation protein synthesis, which mediates the interaction of eIF2 with mRNA. eIF2β contains evolutionarily conserved polylysine stretches in amino-terminal region and a zinc finger motif in the carboxy-terminus. The gene eIF2β was cloned under tetracycline transcription control and the polylysine stretches were deleted by site-directed mutagenesis (eIF2βΔ3K). The plasmid was transfected into HEK 293 TetR cells. These cells were analyzed for their proliferative and translation capacities as well as cell death rate. Experiments were performed using gene reporter assays, western blotting, flow cytometry, cell sorting, cell proliferation assays and confocal immunofluorescence. eIF2βΔ3K affected negatively the protein synthesis, cell proliferation and cell survival causing G2 cell cycle arrest and increased cell death, acting in a negative dominant manner against the native protein. Polylysine stretches are also essential for eIF2β translocated from the cytoplasm to the nucleus, accumulating in the nucleolus and eIF2βΔ3K did not make this translocation. eIF2β is involved in the protein synthesis process and should act in nuclear processes as well. eIF2βΔ3K reduces cell proliferation and causes cell death. Since translation control is essential for normal cell function and survival, the development of drugs or molecules that inhibit translation has become of great interest in the scenario of proliferative disorders. In conclusion, our results suggest the dominant negative eIF2βΔ3K as a therapeutic strategy for the treatment of proliferative disorders and that eIF2β polylysine stretch domains are promising targets for this.

Formononetin promotes cell cycle arrest via downregulation of Akt/Cyclin D1/CDK4 in human prostate cancer cells.

PubMed

Li, Tianyu; Zhao, Xinge; Mo, Zengnan; Huang, Weihua; Yan, Haibiao; Ling, Zhian; Ye, Yu

2014-01-01

Formononetin is an O-methylated isoflavone isolated from the root of Astragalus membranaceus. It has already been reported that formononetin could inhibit cell proliferation and induce cell apoptosis in several cancers, including prostate cancer. This study aimed to further investigate whether cell cycle arrest is involved in formononetin-mediated antitumor effect in human prostate cancer cells, along with the underlying molecular mechanism. Human prostate cancer cells PC-3 and DU145 were respectively treated with various concentrations of formononetin. The inhibitory effect of formononetin on proliferation of prostate cancer cells was determined using MTT assays and flow cytometry. Next, formononetin-induced alterations in cyclin D1, CDK4 and Akt expression in PC-3 cells were detected by real-time PCR and western blot. Formononetin dose-dependently inhibited prostate cancer cell proliferation via the induction of cell cycle arrest at G0/G1 phase in vitro, which was more evident in PC-3 cells. Meanwhile, concomitant with reduced phosphorylation of Akt in PC-3 cells, formononetin remarkably downregulated expression levels of cyclin D1 and CDK4 in a dose-dependent manner. More interestingly, in the in vivo studies, formononetin showed a noticeable inhibition of tumor growth in recipient mice. Formononetin could exhibit inhibitory activity against human prostate cancer cells in vivo and in vitro, which is associated with G1 cell cycle arrest by inactivation of Akt/cyclin D1/CDK4. Therefore, formononetin may be used as a candidate agent for clinical treatment of prostate cancer in the future.

Human reaming debris: a source of multipotent stem cells.

PubMed

Wenisch, Sabine; Trinkaus, Katja; Hild, Anne; Hose, Dirk; Herde, Katja; Heiss, Christian; Kilian, Olaf; Alt, Volker; Schnettler, Reinhard

2005-01-01

The biological characteristics of human reaming debris (HRD) generated in the course of surgical treatment of long bone diaphyseal fractures and nonunions are still a matter of dispute. Therefore, the objective of the present investigation has been to characterize the intrinsic properties of human reaming debris in vitro. Samples of reaming debris harvested from 12 patients with closed diaphyseal fractures were examined ultrastucturally and were cultured under standard conditions. After a lag phase of 4-7 days, cells started to grow out from small bone fragments and established a confluent monolayer within 20-22 days. The cells were characterized according to morphology, proliferation capacity, cell surface antigen profile, and differentiation repertoire. The results reveal that human reaming debris is a source of multipotent stem cells which are able to grow and proliferate in vitro. The cells differentiate along the osteogenic pathway after induction and can be directed toward a neuronal phenotype, as has been shown morphologically and by the expression of neuronal markers after DMSO induction. These findings have prompted interest in the use of reaming debris-derived stem cells in cell and bone replacement therapies.

Effects of Structural Variations on the Cellular Response and Mechanical Properties of Biocompatible, Biodegradable, and Porous Smectic Liquid Crystal Elastomers.

PubMed

Sharma, Anshul; Mori, Taizo; Mahnen, Cory J; Everson, Heather R; Leslie, Michelle T; Nielsen, Alek D; Lussier, Laurent; Zhu, Chenhui; Malcuit, Christopher; Hegmann, Torsten; McDonough, Jennifer A; Freeman, Ernest J; Korley, LaShanda T J; Clements, Robert J; Hegmann, Elda

2017-02-01

The authors report on series of side-chain smectic liquid crystal elastomer (LCE) cell scaffolds based on star block-copolymers featuring 3-arm, 4-arm, and 6-arm central nodes. A particular focus of these studies is placed on the mechanical properties of these LCEs and their impact on cell response. The introduction of diverse central nodes allows to alter and custom-modify the mechanical properties of LCE scaffolds to values on the same order of magnitude of various tissues of interest. In addition, it is continued to vary the position of the LC pendant group. The central node and the position of cholesterol pendants in the backbone of ε-CL blocks (alpha and gamma series) affect the mechanical properties as well as cell proliferation and particularly cell alignment. Cell directionality tests are presented demonstrating that several LCE scaffolds show cell attachment, proliferation, narrow orientational dispersion of cells, and highly anisotropic cell growth on the as-synthesized LCE materials. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

CDKL5, a novel MYCN-repressed gene, blocks cell cycle and promotes differentiation of neuronal cells

PubMed Central

Valli, Emanuele; Trazzi, Stefania; Fuchs, Claudia; Erriquez, Daniela; Bartesaghi, Renata; Perini, Giovanni; Ciani, Elisabetta

2012-01-01

Mutations in the CDKL5 (cyclin-dependent kinase-like 5) gene are associated with a severe epileptic encephalopathy (early infantile epileptic encephalopathy type 2, EIEE2) characterized by early-onset intractable seizures, infantile spasms, severe developmental delay, intellectual disability, and Rett syndrome (RTT)-like features. Despite the clear involvement of CDKL5 mutations in intellectual disability, the function of this protein during brain development and the molecular mechanisms involved in its regulation are still unknown. Using human neuroblastoma cells as a model system we found that an increase in CDKL5 expression caused an arrest of the cell cycle in the G0/G1 phases and induced cellular differentiation. Interestingly, CDKL5 expression was inhibited by MYCN, a transcription factor that promotes cell proliferation during brain development and plays a relevant role in neuroblastoma biology. Through a combination of different and complementary molecular and cellular approaches we could show that MYCN acts as a direct repressor of the CDKL5 promoter. Overall our findings unveil a functional axis between MYCN and CDKL5 governing both neuron proliferation rate and differentiation. The fact that CDKL5 is involved in the control of both neuron proliferation and differentiation may help understand the early appearance of neurological symptoms in patients with mutations in CDKL5. PMID:22921766

Magnetic responsive hydroxyapatite composite scaffolds construction for bone defect reparation.

PubMed

Zeng, Xiao Bo; Hu, Hao; Xie, Li Qin; Lan, Fang; Jiang, Wen; Wu, Yao; Gu, Zhong Wei

2012-01-01

In recent years, interest in magnetic biomimetic scaffolds for tissue engineering has increased considerably. A type of magnetic scaffold composed of magnetic nanoparticles (MNPs) and hydroxyapatite (HA) for bone repair has been developed by our research group. In this study, to investigate the influence of the MNP content (in the scaffolds) on the cell behaviors and the interactions between the magnetic scaffold and the exterior magnetic field, a series of MNP-HA magnetic scaffolds with different MNP contents (from 0.2% to 2%) were fabricated by immersing HA scaffold into MNP colloid. ROS 17/2.8 and MC3T3-E1 cells were cultured on the scaffolds in vitro, with and without an exterior magnetic field, respectively. The cell adhesion, proliferation and differentiation were evaluated via scanning electron microscopy; confocal laser scanning microscopy; and 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), alkaline phosphatase, and bone gla protein activity tests. The results demonstrated the positive influence of the magnetic scaffolds on cell adhesion, proliferation, and differentiation. Further, a higher amount of MNPs on the magnetic scaffolds led to more significant stimulation. The magnetic scaffold can respond to the exterior magnetic field and engender some synergistic effect to intensify the stimulating effect of a magnetic field to the proliferation and differentiation of cells.

Lactate dehydrogenase downregulation mediates the inhibitory effect of diallyl trisulfide on proliferation, metastasis, and invasion in triple-negative breast cancer.

PubMed

Cheng, Shi-Yann; Yang, Yao-Chih; Ting, Kuan-Lun; Wen, Su-Ying; Viswanadha, Vijaya Padma; Huang, Chih-Yang; Kuo, Wei-Wen

2017-04-01

The Warburg effect plays a critical role in tumorigenesis, suggesting that specific agents targeting Warburg effect key proteins may be a promising strategy for cancer therapy. Previous studies have shown that diallyl trisulfide (DATS) inhibits proliferation of breast cancer cells by inducing apoptosis in vitro and in vivo. However, whether the Warburg effect is involved with the apoptosis-promoting action of DATS is unclear. Here, we show that the action of DATS is associated with downregulation of lactate dehydrogenase A (LDHA), an essential protein of the Warburg effect whose upregulation is closely related to tumorigenesis. Interestingly, inhibition of the Warburg effect by DATS in breast cancer cells did not greatly affect normal cells. Furthermore, DATS inhibited growth of breast cancer cells, particularly in MDA-MB-231, a triple-negative breast cancer (TNBC) cell, and reduced proliferation and migration; invasion was reversed by over-expression of LDHA. These data suggest that DATS inhibits breast cancer growth and aggressiveness through a novel pathway targeting the key enzyme of the Warburg effect. Our study shows that LDHA downregulation is involved in the apoptotic effect of DATS on TNBC. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1390-1398, 2017. © 2016 Wiley Periodicals, Inc.

Leucine deprivation inhibits proliferation and induces apoptosis of human breast cancer cells via fatty acid synthase

PubMed Central

Xiao, Fei; Wang, Chunxia; Yin, Hongkun; Yu, Junjie; Chen, Shanghai; Fang, Jing; Guo, Feifan

2016-01-01

Substantial studies on fatty acid synthase (FASN) have focused on its role in regulating lipid metabolism and researchers have a great interest in treating cancer with dietary manipulation of amino acids. In the current study, we found that leucine deprivation caused the FASN-dependent anticancer effect. Here we showed that leucine deprivation inhibited cell proliferation and induced apoptosis of MDA-MB-231 and MCF-7 breast cancer cells. In an in vivo tumor xenograft model, the leucine-free diet suppressed the growth of human breast cancer tumors and triggered widespread apoptosis of the cancer cells. Further study indicated that leucine deprivation decreased expression of lipogenic gene FASN in vitro and in vivo. Over-expression of FASN or supplementation of palmitic acid (the product of FASN action) blocked the effects of leucine deprivation on cell proliferation and apoptosis in vitro and in vivo. Moreover, leucine deprivation suppressed the FASN expression via regulating general control non-derepressible (GCN)2 and sterol regulatory element-binding protein 1C (SREBP1C). Taken together, our study represents proof of principle that anticancer effects can be obtained with strategies to deprive tumors of leucine via suppressing FASN expression, which provides important insights in prevention of breast cancer via metabolic intervention. PMID:27579768

Up-regulation of neogenin-1 increases cell proliferation and motility in gastric cancer

PubMed Central

Kim, Seok-Jun; Wang, Yuan-Guo; Lee, Hyun-Woo; Gu Kang, Hyeok; La, Sun-Hyuk; Ju Choi, Il; Irimura, Tatsuro; Ro, Jae Y.; Bresalier, Robert S.; Chun, Kyung-Hee

2014-01-01

Although elevated expression of neogenin-1 has been detected in human gastric cancer tissue, its role in gastric tumorigenesis remains unclear due to the lack of neogenin-1 studies in cancer. Therefore, we demonstrated here the function and regulatory mechanism of neogenin-1 in gastric cancer. Neogenin-1 ablation decreased proliferation and migration of gastric cancer cells, whereas its over-expression reversed these effects. Xenografted analyses using gastric cancer cells displayed statistically significant inhibition of tumor growth by neogenin-1 depletion. Interestingly, galectin-3 interacted with HSF-1 directly, which facilitated nuclear-localization and binding on neogenin-1 promoter to drive its transcription and gastric cancer cell motility. The galectin-3-increased gastric cancer cell motility was down-regulated by HSF-1 depletion. Moreover, the parallel expression patterns of galectin-3 and neogenin-1, as well as those of HSF-1 and neogenin-1, were detected in the malignant tissues of gastric cancer patients. Taken together, high-expression of neogenin-1 promotes gastric cancer proliferation and motility and its expression is regulated by HSF-1 and galectin-3 interaction. In addition, we propose further studies for neogenin-1 and its associated pathways to provide them as a proper target for gastric cancer therapy. PMID:24930499

Soluble tissue factor has unique angiogenic activities that selectively promote migration and differentiation but not proliferation of endothelial cells

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

He Yingbo; Chang Guodong; Zhan Shunli

2008-06-06

The level of circulating tissue factor (TF) is up-regulated in human angiogenesis-related malignancies. However, whether circulating TF has angiogenic activities has not been determined. Soluble TF (sTF) is the main domain of circulating TF. Here, using cell migration, wound healing, and tubule formation assays, human recombinant sTF was found to significantly promote the migration and differentiation of endothelial cells. The stress fiber formation and rearrangement induced by sTF observed through immunofluorescence microscope may be responsible for the stimulatory migration effect of sTF. Nevertheless, sTF had no effects on endothelial cell proliferation. Interestingly, sTF can be internalized by endothelial cells, whichmore » implies a novel mechanism for sTF in angiogenesis. These results suggest that sTF has unique angiogenic activities and may serve as a potential therapeutic target to treat diseases associated with angiogenesis such as cancer and rheumatoid arthritis.« less

Altered proliferation and networks in neural cells derived from idiopathic autistic individuals.

PubMed

Marchetto, Maria C; Belinson, Haim; Tian, Yuan; Freitas, Beatriz C; Fu, Chen; Vadodaria, Krishna; Beltrao-Braga, Patricia; Trujillo, Cleber A; Mendes, Ana P D; Padmanabhan, Krishnan; Nunez, Yanelli; Ou, Jing; Ghosh, Himanish; Wright, Rebecca; Brennand, Kristen; Pierce, Karen; Eichenfield, Lawrence; Pramparo, Tiziano; Eyler, Lisa; Barnes, Cynthia C; Courchesne, Eric; Geschwind, Daniel H; Gage, Fred H; Wynshaw-Boris, Anthony; Muotri, Alysson R

2017-06-01

Autism spectrum disorders (ASD) are common, complex and heterogeneous neurodevelopmental disorders. Cellular and molecular mechanisms responsible for ASD pathogenesis have been proposed based on genetic studies, brain pathology and imaging, but a major impediment to testing ASD hypotheses is the lack of human cell models. Here, we reprogrammed fibroblasts to generate induced pluripotent stem cells, neural progenitor cells (NPCs) and neurons from ASD individuals with early brain overgrowth and non-ASD controls with normal brain size. ASD-derived NPCs display increased cell proliferation because of dysregulation of a β-catenin/BRN2 transcriptional cascade. ASD-derived neurons display abnormal neurogenesis and reduced synaptogenesis leading to functional defects in neuronal networks. Interestingly, defects in neuronal networks could be rescued by insulin growth factor 1 (IGF-1), a drug that is currently in clinical trials for ASD. This work demonstrates that selection of ASD subjects based on endophenotypes unraveled biologically relevant pathway disruption and revealed a potential cellular mechanism for the therapeutic effect of IGF-1.

miR-181b Promotes hepatic stellate cells proliferation by targeting p27 and is elevated in the serum of cirrhosis patients

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

Wang, Baocan; Li, Wenxi; Guo, Kun

2012-04-27

Highlights: Black-Right-Pointing-Pointer miR-181a and miR-181b, especially, miR-181b could be induced by transforming growth factor-beta 1 (TGF-{beta}1) in hepatic stellate cells. Black-Right-Pointing-Pointer miR-181b could promote HSC-T6 cell proliferation by directly targeting the negative cell regulator-p27 in HSC-T6 cell. Black-Right-Pointing-Pointer miR-181b was identified as potential serum diagnostic marker for liver cirrhosis patients. -- Abstract: MicroRNAs, as a kind of negative gene regulators, were demonstrated to be involved in many types of diseases. In this study, we found that transforming growth factor-beta 1 could induce the expression of miR-181a and miR-181b, and miR-181b increased in the much higher folds than miR-181a. Because ofmore » the important role of transforming growth factor-beta 1 in HSC activation and liver cirrhosis, we investigate the effect of miR-181a and miR-181b on HSC proliferation. The results showed that miR-181b could promote HSC-T6 cell proliferation by regulating cell cycle. Further study showed p27, the cell cycle regulator, was the direct target of miR-181b in HSC-T6 cell. But miR-181a had no effects on HSC-T6 cell proliferation and cell cycle, and did not target p27. Interestingly, miR-181b is elevated significantly in serum of liver cirrhosis cases comparing to that of normal persons, whereas miR-181a expression was in the similar level with that of normal persons. These results suggested that miR-181b could be induced by TGF-{beta}1 and promote the growth of HSCs by directly targeting p27. The elevation of miR-181b in serum suggested that it may be potential diagnostic biomarkers for cirrhosis. As for miR-181a, it may work in TGF-{beta}1 pathway by a currently unknown mechanism.« less

T cell activation and proliferation following acute exercise in human subjects is altered by storage conditions and mitogen selection.

PubMed

Siedlik, Jacob A; Deckert, Jake A; Benedict, Stephen H; Bhatta, Anuja; Dunbar, Amanda J; Vardiman, John P; Gallagher, Philip M

2017-07-01

Recent work investigating exercise induced changes in immunocompetence suggests that some of the ambiguity in the literature is resultant from different cell isolation protocols and mitogen selection. To understand this effect, we compared post-exercise measures of T cell activation and proliferation using two different stimulation methods (costimulation through CD28 or stimulation with phytohaemagglutinin [PHA]). Further, we investigated whether exercise induced changes are maintained when T cell isolation from whole blood is delayed overnight in either a room temperature or chilled (4°C) environment. As expected, an increased proliferation response was observed post-exercise in T cells isolated from whole blood of previously trained individuals immediately after blood collection. Also, cells stimulated with PHA after resting overnight in whole blood were not adversely impacted by the storage conditions. In contrast, allowing cells to rest overnight in whole blood prior to stimulation through CD28, lessened the proliferation observed by cells following exercise rendering both the room temperature and chilled samples closer to the results seen in the control condition. Changes in early markers of activation (CD25), followed a similar pattern, with activation in PHA stimulated cells remaining fairly robust after overnight storage; whereas cell activation following stimulation through CD3+CD28 was disproportionately decreased by the influence of overnight storage. These findings indicate that decisions regarding cell stimulation methods need to be paired with the timeline for T cell isolation from whole blood. These considerations will be especially important for field based studies of immunocompetence where there is a delay in getting whole blood samples to a lab for processing as well as clinical applications where a failure to isolate T cells in a timely manner may result in loss of the response of interest. Copyright © 2017 Elsevier B.V. All rights reserved.

H2S-releasing nanoemulsions: a new formulation to inhibit tumor cells proliferation and improve tissue repair

PubMed Central

Carotenuto, Felicia; Khashoggi, Haneen A.; Nanni, Francesca; Melino, Sonia

2016-01-01

The improvement of solubility and/or dissolution rate of poorly soluble natural compounds is an ideal strategy to make them optimal candidates as new potential drugs. Accordingly, the allyl sulfur compounds and omega-3 fatty acids are natural hydrophobic compounds that exhibit two important combined properties: cardiovascular protection and antitumor activity. Here, we have synthesized and characterized a novel formulation of diallyl disulfide (DADS) and α-linolenic acid (ALA) as protein-nanoemulsions (BAD-NEs), using ultrasounds. BAD-NEs are stable over time at room temperature and show antioxidant and radical scavenging property. These NEs are also optimal H2S slow-release donors and show a significant anti-proliferative effect on different human cancer cell lines: MCF-7 breast cancer and HuT 78 T-cell lymphoma cells. BAD-NEs are able to regulate the ERK1/2 pathway, inducing apoptosis and cell cycle arrest at the G0/G1 phase. We have also investigated their effect on cell proliferation of human adult stem/progenitor cells. Interestingly, BAD-NEs are able to improve the Lin– Sca1+ human cardiac progenitor cells (hCPC) proliferation. This stem cell growth stimulation is combined with the expression and activation of proteins involved in tissue-repair, such as P-AKT, α-sma and connexin 43. Altogether, our results suggest that these antioxidant nanoemulsions might have potential application in selective cancer therapy and for promoting the muscle tissue repair. PMID:27741519

Abnormal cerebellar development and Purkinje cell defects in Lgl1-Pax2 conditional knockout mice.

PubMed

Hou, Congzhe; Ding, Lingcui; Zhang, Jian; Jin, Yecheng; Sun, Chen; Li, Zhenzu; Sun, Xiaoyang; Zhang, Tingting; Zhang, Aizhen; Li, Huashun; Gao, Jiangang

2014-11-01

Lgl1 was initially identified as a tumour suppressor in flies and is characterised as a key regulator of epithelial polarity and asymmetric cell division. A previous study indicated that More-Cre-mediated Lgl1 knockout mice exhibited significant brain dysplasia and died within 24h after birth. To overcome early neonatal lethality, we generated Lgl1 conditional knockout mice mediated by Pax2-Cre, which is expressed in almost all cells in the cerebellum, and we examined the functions of Lgl1 in the cerebellum. Impaired motor coordination was detected in the mutant mice. Consistent with this abnormal behaviour, homozygous mice possessed a smaller cerebellum with fewer lobes, reduced granule precursor cell (GPC) proliferation, decreased Purkinje cell (PC) quantity and dendritic dysplasia. Loss of Lgl1 in the cerebellum led to hyperproliferation and impaired differentiation of neural progenitors in ventricular zone. Based on the TUNEL assay, we observed increased apoptosis in the cerebellum of mutant mice. We proposed that impaired differentiation and increased apoptosis may contribute to decreased PC quantity. To clarify the effect of Lgl1 on cerebellar granule cells, we used Math1-Cre to specifically delete Lgl1 in granule cells. Interestingly, the Lgl1-Math1 conditional knockout mice exhibited normal proliferation of GPCs and cerebellar development. Thus, we speculated that the reduction in the proliferation of GPCs in Lgl1-Pax2 conditional knockout mice may be secondary to the decreased number of PCs, which secrete the mitogenic factor Sonic hedgehog to regulate GPC proliferation. Taken together, these findings suggest that Lgl1 plays a key role in cerebellar development and folia formation by regulating the development of PCs. Copyright © 2014. Published by Elsevier Inc.

Automated mitosis detection of stem cell populations in phase-contrast microscopy images.

PubMed

Huh, Seungil; Ker, Dai Fei Elmer; Bise, Ryoma; Chen, Mei; Kanade, Takeo

2011-03-01

Due to the enormous potential and impact that stem cells may have on regenerative medicine, there has been a rapidly growing interest for tools to analyze and characterize the behaviors of these cells in vitro in an automated and high throughput fashion. Among these behaviors, mitosis, or cell division, is important since stem cells proliferate and renew themselves through mitosis. However, current automated systems for measuring cell proliferation often require destructive or sacrificial methods of cell manipulation such as cell lysis or in vitro staining. In this paper, we propose an effective approach for automated mitosis detection using phase-contrast time-lapse microscopy, which is a nondestructive imaging modality, thereby allowing continuous monitoring of cells in culture. In our approach, we present a probabilistic model for event detection, which can simultaneously 1) identify spatio-temporal patch sequences that contain a mitotic event and 2) localize a birth event, defined as the time and location at which cell division is completed and two daughter cells are born. Our approach significantly outperforms previous approaches in terms of both detection accuracy and computational efficiency, when applied to multipotent C3H10T1/2 mesenchymal and C2C12 myoblastic stem cell populations.

The real factor for polypeptide elongation in Dictyostelium cells is EF-2B, not EF-2A

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

Yoshino, Tomoko; Maeda, Yasuo; Amagai, Aiko

2007-08-03

Polypeptide elongation factor 2 (EF-2) plays an essential role in protein synthesis and is believed to be indispensable for cell proliferation. Recently, it has been demonstrated that there are two kinds of EF-2 (EF-2A and EF-2B with 76.6% of sequence identity at the amino acid level) in Dictyostelium discoideum. Although the knockout of EF-2A slightly impaired cytokinesis, EF-2A null cells exhibited almost normal protein synthesis and cell growth, suggesting that there is another molecule capable of compensating for EF-2 function. Since EF-2B is the most likely candidate, we examined its function using ef-2b knockdown cells prepared by the RNAi method.more » Our results strongly suggest that EF-2B is required for protein synthesis and cell proliferation, functioning as the real EF-2. Interestingly, the expressions of ef-2a and ef-2b mRNAs during development are reversely regulated, and the ef-2b expression is greatly augmented in ef-2a null cells.« less

Aging increases microglial proliferation, delays cell migration, and decreases cortical neurogenesis after focal cerebral ischemia.

PubMed

Moraga, Ana; Pradillo, Jesús M; García-Culebras, Alicia; Palma-Tortosa, Sara; Ballesteros, Ivan; Hernández-Jiménez, Macarena; Moro, María A; Lizasoain, Ignacio

2015-05-10

Aging is not just a risk factor of stroke, but it has also been associated with poor recovery. It is known that stroke-induced neurogenesis is reduced but maintained in the aged brain. However, there is no consensus on how neurogenesis is affected after stroke in aged animals. Our objective is to determine the role of aging on the process of neurogenesis after stroke. We have studied neurogenesis by analyzing proliferation, migration, and formation of new neurons, as well as inflammatory parameters, in a model of cerebral ischemia induced by permanent occlusion of the middle cerebral artery in young- (2 to 3 months) and middle-aged mice (13 to 14 months). Aging increased both microglial proliferation, as shown by a higher number of BrdU(+) cells and BrdU/Iba1(+) cells in the ischemic boundary and neutrophil infiltration. Interestingly, aging increased the number of M1 monocytes and N1 neutrophils, consistent with pro-inflammatory phenotypes when compared with the alternative M2 and N2 phenotypes. Aging also inhibited (subventricular zone) SVZ cell proliferation by decreasing both the number of astrocyte-like type-B (prominin-1(+)/epidermal growth factor receptor (EGFR)(+)/nestin(+)/glial fibrillary acidic protein (GFAP)(+) cells) and type-C cells (prominin-1(+)/EGFR(+)/nestin(-)/Mash1(+) cells), and not affecting apoptosis, 1 day after stroke. Aging also inhibited migration of neuroblasts (DCX(+) cells), as indicated by an accumulation of neuroblasts at migratory zones 14 days after injury; consistently, aged mice presented a smaller number of differentiated interneurons (NeuN(+)/BrdU(+) and GAD67(+) cells) in the peri-infarct cortical area 14 days after stroke. Our data confirm that stroke-induced neurogenesis is maintained but reduced in aged animals. Importantly, we now demonstrate that aging not only inhibits proliferation of specific SVZ cell subtypes but also blocks migration of neuroblasts to the damaged area and decreases the number of new interneurons in the cortical peri-infarct area. Thus, our results highlight the importance of using aged animals for translation to clinical studies.

Opposite Interplay Between the Canonical WNT/β-Catenin Pathway and PPAR Gamma: A Potential Therapeutic Target in Gliomas.

PubMed

Vallée, Alexandre; Lecarpentier, Yves; Guillevin, Rémy; Vallée, Jean-Noël

2018-06-01

In gliomas, the canonical Wingless/Int (WNT)/β-catenin pathway is increased while peroxisome proliferator-activated receptor gamma (PPAR-γ) is downregulated. The two systems act in an opposite manner. This review focuses on the interplay between WNT/β-catenin signaling and PPAR-γ and their metabolic implications as potential therapeutic target in gliomas. Activation of the WNT/β-catenin pathway stimulates the transcription of genes involved in proliferation, invasion, nucleotide synthesis, tumor growth, and angiogenesis. Activation of PPAR-γ agonists inhibits various signaling pathways such as the JAK/STAT, WNT/β-catenin, and PI3K/Akt pathways, which reduces tumor growth, cell proliferation, cell invasiveness, and angiogenesis. Nonsteroidal anti-inflammatory drugs, curcumin, antipsychotic drugs, adiponectin, and sulforaphane downregulate the WNT/β-catenin pathway through the upregulation of PPAR-γ and thus appear to provide an interesting therapeutic approach for gliomas. Temozolomide (TMZ) is an antiangiogenic agent. The downstream action of this opposite interplay may explain the TMZ-resistance often reported in gliomas.

Uncaria rhynchophylla induces angiogenesis in vitro and in vivo.

PubMed

Choi, Do-Young; Huh, Jeong-Eun; Lee, Jae-Dong; Cho, Eun-Mi; Baek, Yong-Hyeon; Yang, Ha-Ru; Cho, Yoon-Je; Kim, Kang-Il; Kim, Deog-Yoon; Park, Dong-Suk

2005-12-01

Angiogenesis consists of the proliferation, migration, and differentiation of endothelial cells, and angiogenic factors and matrix protein interactions modulate this process. The aim of this study was to determine the angiogenic properties of Uncaria rhynchophylla. Uncaria rhynchophylla significantly enhanced human umbilical vein endothelial cells (HUVECs) proliferation in a dose-dependent manner. Neutralization of vascular endothelial growth factor (VEGF) or basic fibroblast growth factor (bFGF) by monoclonal antibody suppressed the Uncaria rhynchophylla stimulatory effect on proliferation. In addition, Uncaria rhynchophylla significantly increased chemotactic-migration on gelatin and tubular structures on Matrigel of HUVECs in a dose-dependent manner. Interestingly, Uncaria rhynchophylla dose-dependently increased VEGF, and bFGF gene expression and protein secretion of HUVEC. The angiogenic activity of Uncaria rhynchophylla was confirmed using an in vivo Matrigel angiogenesis model, showing promotion of blood vessel formation. These results suggest that Uncaria rhynchophylla could potentially used to accelerate vascular wound healing or to promote the growth of collateral blood vessel in ischemic tissues.

The role of growth factors in maintenance of stemness in bone marrow-derived mesenchymal stem cells

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

Eom, Young Woo; Oh, Ji-Eun; Lee, Jong In

2014-02-28

Highlights: • Expression of FGF-2, FGF-4, EGF, and HGF decreased during long-term culture of BMSCs. • Loss of growth factors induced autophagy, senescence and decrease of stemness. • FGF-2 increased proliferation potential via AKT and ERK activation in BMSCs. • FGF-2 suppressed LC3-II expression and down-regulated senescence of BMSCs. • HGF was important in maintenance of the differentiation potential of BMSCs. - Abstract: Mesenchymal stem cells (MSCs) are an active topic of research in regenerative medicine due to their ability to secrete a variety of growth factors and cytokines that promote healing of damaged tissues and organs. In addition, thesemore » secreted growth factors and cytokines have been shown to exert an autocrine effect by regulating MSC proliferation and differentiation. We found that expression of EGF, FGF-4 and HGF were down-regulated during serial passage of bone marrow-derived mesenchymal stem cells (BMSCs). Proliferation and differentiation potentials of BMSCs treated with these growth factors for 2 months were evaluated and compared to BMSCs treated with FGF-2, which increased proliferation of BMSCs. FGF-2 and -4 increased proliferation potentials at high levels, about 76- and 26-fold, respectively, for 2 months, while EGF and HGF increased proliferation of BMSCs by less than 2.8-fold. Interestingly, differentiation potential, especially adipogenesis, was maintained only by HGF treatment. Treatment with FGF-2 rapidly induced activation of AKT and later induced ERK activation. The basal level of phosphorylated ERK increased during serial passage of BMSCs treated with FGF-2. The expression of LC3-II, an autophagy marker, was gradually increased and the population of senescent cells was increased dramatically at passage 7 in non-treated controls. But FGF-2 and FGF-4 suppressed LC3-II expression and down-regulated senescent cells during long-term (i.e. 2 month) cultures. Taken together, depletion of growth factors during serial passage could induce autophagy, senescence and down-regulation of stemness (proliferation via FGF-2/-4 and differentiation via HGF) through suppression of AKT and ERK signaling.« less

Metformin selectively affects human glioblastoma tumor-initiating cell viability: A role for metformin-induced inhibition of Akt.

PubMed

Würth, Roberto; Pattarozzi, Alessandra; Gatti, Monica; Bajetto, Adirano; Corsaro, Alessandro; Parodi, Alessia; Sirito, Rodolfo; Massollo, Michela; Marini, Cecilia; Zona, Gianluigi; Fenoglio, Daniela; Sambuceti, Gianmario; Filaci, Gilberto; Daga, Antonio; Barbieri, Federica; Florio, Tullio

2013-01-01

Cancer stem cell theory postulates that a small population of tumor-initiating cells is responsible for the development, progression and recurrence of several malignancies, including glioblastoma. In this perspective, tumor-initiating cells represent the most relevant target to obtain effective cancer treatment. Metformin, a first-line drug for type II diabetes, was reported to possess anticancer properties affecting the survival of cancer stem cells in breast cancer models. We report that metformin treatment reduced the proliferation rate of tumor-initiating cell-enriched cultures isolated from four human glioblastomas. Metformin also impairs tumor-initiating cell spherogenesis, indicating a direct effect on self-renewal mechanisms. Interestingly, analyzing by FACS the antiproliferative effects of metformin on CD133-expressing subpopulation, a component of glioblastoma cancer stem cells, a higher reduction of proliferation was observed as compared with CD133-negative cells, suggesting a certain degree of cancer stem cell selectivity in its effects. In fact, glioblastoma cell differentiation strongly reduced sensitivity to metformin treatment. Metformin effects in tumor-initiating cell-enriched cultures were associated with a powerful inhibition of Akt-dependent cell survival pathway, while this pathway was not affected in differentiated cells. The specificity of metformin antiproliferative effects toward glioblastoma tumor-initiating cells was confirmed by the lack of significant inhibition of normal human stem cells (umbilical cord-derived mesenchymal stem cells) in vitro proliferation after metformin exposure. Altogether, these data clearly suggest that metformin exerts antiproliferative activity on glioblastoma cells, showing a higher specificity toward tumor-initiating cells, and that the inhibition of Akt pathway may represent a possible intracellular target of this effect.

Hoxb4 overexpression in CD4 memory phenotype T cells increases the central memory population upon homeostatic proliferation.

PubMed

Frison, Héloïse; Giono, Gloria; Thébault, Paméla; Fournier, Marilaine; Labrecque, Nathalie; Bijl, Janet J

2013-01-01

Memory T cell populations allow a rapid immune response to pathogens that have been previously encountered and thus form the basis of success in vaccinations. However, the molecular pathways underlying the development and maintenance of these cells are only starting to be unveiled. Memory T cells have the capacity to self renew as do hematopoietic stem cells, and overlapping gene expression profiles suggested that these cells might use the same self-renewal pathways. The transcription factor Hoxb4 has been shown to promote self-renewal divisions of hematopoietic stem cells resulting in an expansion of these cells. In this study we investigated whether overexpression of Hoxb4 could provide an advantage to CD4 memory phenotype T cells in engrafting the niche of T cell deficient mice following adoptive transfer. Competitive transplantation experiments demonstrated that CD4 memory phenotype T cells derived from mice transgenic for Hoxb4 contributed overall less to the repopulation of the lymphoid organs than wild type CD4 memory phenotype T cells after two months. These proportions were relatively maintained following serial transplantation in secondary and tertiary mice. Interestingly, a significantly higher percentage of the Hoxb4 CD4 memory phenotype T cell population expressed the CD62L and Ly6C surface markers, characteristic for central memory T cells, after homeostatic proliferation. Thus Hoxb4 favours the maintenance and increase of the CD4 central memory phenotype T cell population. These cells are more stem cell like and might eventually lead to an advantage of Hoxb4 T cells after subjecting the cells to additional rounds of proliferation.

How does metabolism affect cell death in cancer?

PubMed

Villa, Elodie; Ricci, Jean-Ehrland

2016-07-01

In cancer research, identifying a specificity of tumor cells compared with 'normal' proliferating cells for targeted therapy is often considered the Holy Grail for researchers and clinicians. Although diverse in origin, most cancer cells share characteristics including the ability to escape cell death mechanisms and the utilization of different methods of energy production. In the current paradigm, aerobic glycolysis is considered the central metabolic characteristic of cancer cells (Warburg effect). However, recent data indicate that cancer cells also show significant changes in other metabolic pathways. Indeed, it was recently suggested that Kreb's cycle, pentose phosphate pathway intermediates, and essential and nonessential amino acids have key roles. Renewed interest in the fact that cancer cells have to reprogram their metabolism in order to proliferate or resist treatment must take into consideration the ability of tumor cells to adapt their metabolism to the local microenvironment (low oxygen, low nutrients). This variety of metabolic sources might be either a strength, resulting in infinite possibilities for adaptation and increased ability to resist chemotherapy-induced death, or a weakness that could be targeted to kill cancer cells. Here, we discuss recent insights showing how energetic metabolism may regulate cell death and how this might be relevant for cancer treatment. © 2015 FEBS.

Hypoxia Inducible Factor-Stabilizing Bioactive Glasses for Directing Mesenchymal Stem Cell Behavior

PubMed Central

Azevedo, Maria M.; Tsigkou, Olga; Nair, Rekha; Jones, Julian R.; Jell, Gavin

2015-01-01

Oxygen tension is a known regulator of mesenchymal stem cell (MSC) plasticity, differentiation, proliferation, and recruitment to sites of injury. Materials capable of affecting the MSC oxygen-sensing pathway, independently of the environmental oxygen pressure, are therefore of immense interest to the tissue engineering (TE) and regenerative medicine community. In this study, we describe the evaluation of the effect of hypoxia inducible factor (HIF)-stabilizing bioactive glasses (BGs) on human MSCs. The dissolution products from these hypoxia-mimicking BGs stabilized HIF-1α in a concentration-dependent manner, altered cell proliferation and metabolism, and upregulated a number of genes involved in the hypoxic response (HIF1A, HIF2A, and VHL), MSC survival (SAG and BCL2), extracellular matrix remodeling (MMP1), and angiogenesis (VEGF and PDGF). These HIF-stabilizing materials can therefore be used to improve MSC survival and enhance regeneration in a number of TE strategies. PMID:25167933

Targeting Heat Shock Proteins in Cancer: A Promising Therapeutic Approach.

PubMed

Chatterjee, Suman; Burns, Timothy F

2017-09-15

Heat shock proteins (HSPs) are a large family of chaperones that are involved in protein folding and maturation of a variety of "client" proteins protecting them from degradation, oxidative stress, hypoxia, and thermal stress. Hence, they are significant regulators of cellular proliferation, differentiation and strongly implicated in the molecular orchestration of cancer development and progression as many of their clients are well established oncoproteins in multiple tumor types. Interestingly, tumor cells are more HSP chaperonage-dependent than normal cells for proliferation and survival because the oncoproteins in cancer cells are often misfolded and require augmented chaperonage activity for correction. This led to the development of several inhibitors of HSP90 and other HSPs that have shown promise both preclinically and clinically in the treatment of cancer. In this article, we comprehensively review the roles of some of the important HSPs in cancer, and how targeting them could be efficacious, especially when traditional cancer therapies fail.

Bone regeneration performance of surface-treated porous titanium.

PubMed

Amin Yavari, Saber; van der Stok, Johan; Chai, Yoke Chin; Wauthle, Ruben; Tahmasebi Birgani, Zeinab; Habibovic, Pamela; Mulier, Michiel; Schrooten, Jan; Weinans, Harrie; Zadpoor, Amir Abbas

2014-08-01

The large surface area of highly porous titanium structures produced by additive manufacturing can be modified using biofunctionalizing surface treatments to improve the bone regeneration performance of these otherwise bioinert biomaterials. In this longitudinal study, we applied and compared three types of biofunctionalizing surface treatments, namely acid-alkali (AcAl), alkali-acid-heat treatment (AlAcH), and anodizing-heat treatment (AnH). The effects of treatments on apatite forming ability, cell attachment, cell proliferation, osteogenic gene expression, bone regeneration, biomechanical stability, and bone-biomaterial contact were evaluated using apatite forming ability test, cell culture assays, and animal experiments. It was found that AcAl and AnH work through completely different routes. While AcAl improved the apatite forming ability of as-manufactured (AsM) specimens, it did not have any positive effect on cell attachment, cell proliferation, and osteogenic gene expression. In contrast, AnH did not improve the apatite forming ability of AsM specimens but showed significantly better cell attachment, cell proliferation, and expression of osteogenic markers. The performance of AlAcH in terms of apatite forming ability and cell response was in between both extremes of AnH and AsM. AcAl resulted in significantly larger volumes of newly formed bone within the pores of the scaffold as compared to AnH. Interestingly, larger volumes of regenerated bone did not translate into improved biomechanical stability as AnH exhibited significantly better biomechanical stability as compared to AcAl suggesting that the beneficial effects of cell-nanotopography modulations somehow surpassed the benefits of improved apatite forming ability. In conclusion, the applied surface treatments have considerable effects on apatite forming ability, cell attachment, cell proliferation, and bone ingrowth of the studied biomaterials. The relationship between these properties and the bone-implant biomechanics is, however, not trivial. Copyright © 2014 Elsevier Ltd. All rights reserved.

Profile of cell proliferation and apoptosis activated by the intrinsic and extrinsic pathways in the prostate of aging rats.

PubMed

Gonzaga, Amanda C R; Campolina-Silva, Gabriel H; Werneck-Gomes, Hipácia; Moura-Cordeiro, Júnia D; Santos, Letícia C; Mahecha, Germán A B; Morais-Santos, Mônica; Oliveira, Cleida A

2017-06-01

Estrogens acting through the receptors ERα and ERβ participate in prostate normal growth and cancer. ERβ is highly expressed in the prostate epithelium, playing pro-apoptotic, anti-proliferative, and pro-differentiation roles. Apoptosis is activated by the intrinsic pathway after castration and by the extrinsic pathway after ERβ agonist treatment. This differential activation of apoptotic pathways is important since a major problem in the treatment of prostate cancer is the recurrence of tumors after androgen withdrawal. However, a comprehensive study about the pattern of apoptosis in the aging prostate is lacking, a knowledge gap that we aimed to address herein. Cellular age-related proliferative and apoptotic profiles of prostate tissue obtained from aging Wistar rats were evaluated. Cell death (caspase-3, -8, -9, TNFα) was assessed by immunohistochemistry, immunofluorescence, and TUNEL. Cell proliferation (MCM7) and cell survival factors (ERK1/2, p-ERK1/2, p-Akt, and NF-κB) were determined by immunohistochemistry. As the rats aged, the number of proliferating cells gradually reduced in the normal epithelium of all prostate lobes, while increasing in focal areas of intraepithelial proliferation. Interestingly, in areas of intraepithelial proliferation, we observed a reduction in the number of cells positive for caspase-3, -8, and -9. Regardless the animal's age, few prostate epithelial cells were positive for caspase-3, caspase-9, and TUNEL. In contrast, a progressive increase was seen in the positivity for caspase-8, especially in the atrophic epithelium of ventral prostate, which coincided with a reduction in TNFα immunoreaction. However, morphology of most caspase-8 positive cells suggests that they were not apoptotic. We also found reduced ERβ expression in the same areas. Possibly, low levels of the pro-apoptotic inductors TNFα and ERβ direct caspase-8 activity to an alternative pro-survival role in the atrophic epithelium. This hypothesis is supported by the increased expression of the key survival factors (ERK1/2, p-ERK1/2, p-Akt, and NF-κB) in these areas. Our findings reveal that, as the animals age, there is an increase of proliferation in restricted areas of the prostate epithelium, and a concomitant reduction of the apoptosis rate with an increase in cell survival induced by caspase-8, indicating a focused and spontaneous disruption of tissue homeostasis. © 2017 Wiley Periodicals, Inc.

MiR-30e suppresses proliferation of hepatoma cells via targeting prolyl 4-hydroxylase subunit alpha-1 (P4HA1) mRNA

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

Feng, Guoxing; Shi, Hui; Li, Jiong

Aberrant microRNA expression has been shown to be characteristic of many cancers. It has been reported that the expression levels of miR-30e are decreased in liver cancer tissues. However, the role of miR-30e in hepatocellular carcinoma remains poorly understood. In the present study, we investigated the significance of miR-30e in hepatocarcinogenesis. Bioinformatics analysis reveals a putative target site of miR-30e in the 3′-untranslated region (3′UTR) of prolyl 4-hydroxylase subunit alpha-1 (P4HA1) mRNA. Moreover, luciferase reporter gene assays verified that miR-30e directly targeted 3′UTR of P4HA1 mRNA. Then, we demonstrated that miR-30e was able to reduce the expression of P4HA1 atmore » the levels of mRNA and protein using reverse transcription-polymerase chain reaction and Western blot analysis. Enforced expression of miR-30e suppressed proliferation of HepG2 cells by 5-ethynyl-2-deoxyuridine (EdU) assay and reduced colony formation of these cells by colony formation analysis. Conversely, anti-miR-30e enhanced the proliferation of hepatoma cells in vitro. Interestingly, the ectopic expression of P4HA1 could efficiently rescue the inhibition of cell proliferation mediated by miR-30e in HepG2 cells. Meanwhile, silencing of P4HA1 abolished the anti-miR-30e-induced proliferation of cells. Clinically, quantitative real-time PCR showed that miR-30e was down-regulated in liver tumor tissues relative to their peritumor tissues. The expression levels of miR-30e were negatively correlated to those of P4HA1 mRNA in clinical liver tumor tissues. Thus, we conclude that miR-30e suppresses proliferation of hepatoma cells through targeting P4HA1 mRNA. Our finding provides new insights into the mechanism of hepatocarcinogenesis. - Highlights: • P4HA1 is a novel target gene of miR-30e. • P4HA1 is increased in clinical HCC tissues. • MiR-30e is negatively correlated with P4HA1 in clinical HCC tissues. • MiR-30e suppresses the proliferation of HCC cells through targeting P4HA1 mRNA.« less

USP7 promotes cell proliferation through the stabilization of Ki-67 protein in non-small cell lung cancer cells.

PubMed

Zhang, Chao; Lu, Jing; Zhang, Quan-Wu; Zhao, Wei; Guo, Jia-Hui; Liu, Shan-Ling; Wu, Ying-Li; Jiang, Bin; Gao, Feng-Hou

2016-10-01

The Ki-67 antigen (Ki-67) is the most reliable immunohistochemical marker for evaluation of cell proliferation in non-small cell lung cancer. However, the mechanisms underlying the regulation of protein levels of Ki-67 in non-small cell lung cancer have remained elusive. In this study, we found that Ki-67 and ubiquitin-specific processing protease 7 (USP7) protein were highly expressed in the nucleus of non-small cell lung cancer cells. Furthermore, statistical analysis uncovered the existence of a strong correlation between Ki-67 and USP7 levels. We could also show that the protein levels of Ki-67 in non-small cell lung cancer cells significantly decreased after treatment with P22077, a selective chemical inhibitor of USP7, while the Ki-67 mRNA levels were unperturbed. Similar results were obtained by knocking down USP7 using short hairpin RNA (shRNA) in lung cancer cells. Interestingly, we noticed that ubiquitination levels of Ki-67 increased dramatically in USP7-silenced cells. The tests in vitro and vivo showed a significant delay in tumor cell growth upon knockdown of USP7. Additionally, drug sensitivity tests indicated that USP7-silenced A549 cells had enhanced sensitivity to paclitaxel and docetaxel, while there was no significant change in sensitivity toward carboplatin and cisplatin. Taken together, these data strongly suggest that the overexpression of USP7 might promote cell proliferation by deubiquitinating Ki-67 protein, thereby maintaining its high levels in the non-small cell lung cancer. Our study also hints potential for the development of deubiquitinase-based therapies, especially those targeting USP7 to improve the condition of patients diagnosed with non-small cell lung cancer. Copyright © 2016 Elsevier Ltd. All rights reserved.

Heparin affin regulatory peptide/pleiotrophin negatively affects diverse biological activities in C6 glioma cells.

PubMed

Parthymou, Anastasia; Lampropoulou, Evgenia; Mikelis, Constantinos; Drosou, Georgia; Papadimitriou, Evangelia

2008-01-01

Heparin affin regulatory peptide (HARP) or pleiotrophin seems to be involved in the progression of several tumors of diverse origin. In this study, we tried to determine the role of HARP in rat C6 glioma cells by using an antisense strategy for inhibition of HARP expression. Decrease of the expression of endogenous HARP in C6 cells (AS-C6 cells) significantly increased proliferation, migration, and anchorage-independent growth of cells. Implantation of AS-C6 cells onto chicken embryo chorioallantoic membranes resulted in a significant increase of tumor-induced angiogenesis compared with that induced by non-transfected or C6 cells transfected with the plasmid alone (PC-C6 cells). In the same line, conditioned medium from AS-C6 cells significantly increased endothelial cell proliferation, migration, and tube formation in vitro compared with the effect of conditioned medium from C6 or PC-C6 cells. Interestingly, vascular endothelial growth factor (VEGF) induced C6 cell proliferation and migration, and SU1496, a selective inhibitor of VEGF receptor 2 (VEGFR2), blocked increased glioma cell growth, migration, and angiogenicity observed in AS-C6 cell cultures. The above results seem to be due to a direct interaction between HARP and VEGF in the culture medium of C6 and PC-C6 cells, while AS-C6 cells secreted comparable amounts of VEGF that do not interact with HARP. Collectively, these data suggest that HARP negatively affects diverse biological activities in C6 glioma cells, mainly due to binding of HARP to VEGF, which may sequester secreted VEGF from signalling through VEGFR2.

Chronic but not acute foot-shock stress leads to temporary suppression of cell proliferation in rat hippocampus.

PubMed

Dagyte, G; Van der Zee, E A; Postema, F; Luiten, P G M; Den Boer, J A; Trentani, A; Meerlo, P

2009-09-15

Stressful experiences, especially when prolonged and severe are associated with psychopathology and impaired neuronal plasticity. Among other effects on the brain, stress has been shown to negatively regulate hippocampal neurogenesis, and this effect is considered to be exerted via glucocorticoids. Here, we sought to determine the temporal dynamics of changes in hippocampal neurogenesis after acute and chronic exposure to foot-shock stress. Rats subjected to a foot-shock procedure showed strong activation of the hypothalamic-pituitary-adrenal (HPA) axis, even after exposure to daily stress for 3 weeks. Despite a robust release of corticosterone, acute foot-shock stress did not affect the rate of hippocampal cell proliferation. In contrast, exposure to foot-shock stress daily for 3 weeks led to reduced cell proliferation 2 hours after the stress procedure. Interestingly, this stress-induced effect did not persist and was no longer detected 24 hours later. Also, while chronic foot-shock stress had no impact on survival of hippocampal cells that were born before the stress procedure, it led to a decreased number of doublecortin-positive granule neurons that were born during the chronic stress period. Thus, whereas a strong activation of the HPA axis during acute foot-shock stress is not sufficient to reduce hippocampal cell proliferation, repeated exposure to stressful stimuli for prolonged period of time ultimately results in dysregulated neurogenesis. In sum, this study supports the notion that chronic stress may lead to cumulative changes in the brain that are not seen after acute stress. Such changes may indicate compromised brain plasticity and increased vulnerability to neuropathology.

Allium sativum L. regulates in vitro IL-17 gene expression in human peripheral blood mononuclear cells.

PubMed

Moutia, Mouna; Seghrouchni, Fouad; Abouelazz, Omar; Elouaddari, Anass; Al Jahid, Abdellah; Elhou, Abdelhalim; Nadifi, Sellama; Jamal Eddine, Jamal; Habti, Norddine; Badou, Abdallah

2016-09-29

Allium sativum L. (A.S.) "garlic", one of the most interesting medicinal plants, has been suggested to contain compounds that could be beneficial in numerous pathological situations including cancer. In this work, we aimed to assess the immunomodulatory effect of A.S. preparation on human peripheral blood mononuclear cells from healthy individuals. Nontoxic doses of A.S. were identified using MTT assay. Effects on CD4+ or CD8+ T lymphocyte proliferation were studied using flow cytometry. The effect of A.S. on cytokine gene expression was studied using qRT-PCR. Finally, qualitative analysis of A.S. was performed by HPLC approach. Data were analyzed statistically by one-way ANOVA test. The nontoxic doses of A.S. preparation did not affect neither spontaneous nor TCR-mediated CD4+ or CD8+ T lymphocyte proliferation. Interestingly, A.S. exhibited a statistically significant regulation of IL-17 gene expression, a cytokine involved in several inflammatory and autoimmune diseases. In contrast, the expression of IL-4, an anti-inflammatory cytokine, was unaffected. Qualitative analysis of A.S. ethanol preparation indicated the presence of three polyphenol bioactive compounds, which are catechin, vanillic acid and ferulic acid. The specific inhibition of the pro-inflammatory cytokine, IL-17 without affecting cell proliferation in human PBMCs by the Allium sativum L. preparation suggests a potential valuable effect of the compounds present in this plant for the treatment of inflammatory diseases and cancer, where IL-17 is highly expressed. The individual contribution of these three compounds to this global effect will be assessed.

Tbx1 Regulates Progenitor Cell Proliferation in the Dental Epithelium by Modulating PITX2 Activation of p21

PubMed Central

Cao, Huojun; Florez, Sergio; Amen, Melanie; Huynh, Tuong; Skobe, Ziedonis; Baldini, Antonio; Amendt, Brad A.

2012-01-01

Tbx1−/− mice present with phenotypic effects observed in DiGeorge syndrome patients however, the molecular mechanisms of Tbx1 regulating craniofacial and tooth development are unclear. Analyses of the Tbx1 null mice reveal incisor microdontia, small cervical loops and BrdU labeling reveals a defect in epithelial cell proliferation. Furthermore, Tbx1 null mice molars are lacking normal cusp morphology. Interestingly, p21 (associated with cell cycle arrest) is up regulated in the dental epithelium of Tbx1−/− embryos. These data suggest that Tbx1 inhibits p21 expression to allow for cell proliferation in the dental epithelial cervical loop, however Tbx1 does not directly regulate p21 expression. A new molecular mechanism has been identified where Tbx1 inhibits Pitx2 transcriptional activity and decreases the expression of Pitx2 target genes, p21, Lef-1 and Pitx2c. p21 protein is increased in PITX2C transgenic mouse embryo fibroblasts (MEF) and chromatin immunoprecipitation assays demonstrate endogenous Pitx2 binding to the p21 promoter. Tbx1 attenuates PITX2 activation of endogenous p21 expression and Tbx1 null MEFs reveal increased Pitx2a and activation of Pitx2c isoform expression. Tbx1 physically interacts with the PITX2 C-terminus and represses PITX2 transcriptional activation of the p21, LEF-1, and Pitx2c promoters. Tbx1−/+/Pitx2−/+ double heterozygous mice present with an extra premolar-like tooth revealing a genetic interaction between these factors. The ability of Tbx1 to repress PITX2 activation of p21 may promote cell proliferation. In addition, PITX2 regulation of p21 reveals a new role for PITX2 in repressing cell proliferation. These data demonstrate new functional mechanisms for Tbx1 in tooth morphogenesis and provide a molecular basis for craniofacial defects in DiGeorge syndrome patients. PMID:20816801

Tbx1 regulates progenitor cell proliferation in the dental epithelium by modulating Pitx2 activation of p21.

PubMed

Cao, Huojun; Florez, Sergio; Amen, Melanie; Huynh, Tuong; Skobe, Ziedonis; Baldini, Antonio; Amendt, Brad A

2010-11-15

Tbx1(-/-) mice present with phenotypic effects observed in DiGeorge syndrome patients however, the molecular mechanisms of Tbx1 regulating craniofacial and tooth development are unclear. Analyses of the Tbx1 null mice reveal incisor microdontia, small cervical loops and BrdU labeling reveals a defect in epithelial cell proliferation. Furthermore, Tbx1 null mice molars are lacking normal cusp morphology. Interestingly, p21 (associated with cell cycle arrest) is up regulated in the dental epithelium of Tbx1(-/-) embryos. These data suggest that Tbx1 inhibits p21 expression to allow for cell proliferation in the dental epithelial cervical loop, however Tbx1 does not directly regulate p21 expression. A new molecular mechanism has been identified where Tbx1 inhibits Pitx2 transcriptional activity and decreases the expression of Pitx2 target genes, p21, Lef-1 and Pitx2c. p21 protein is increased in PITX2C transgenic mouse embryo fibroblasts (MEF) and chromatin immunoprecipitation assays demonstrate endogenous Pitx2 binding to the p21 promoter. Tbx1 attenuates PITX2 activation of endogenous p21 expression and Tbx1 null MEFs reveal increased Pitx2a and activation of Pitx2c isoform expression. Tbx1 physically interacts with the PITX2 C-terminus and represses PITX2 transcriptional activation of the p21, LEF-1, and Pitx2c promoters. Tbx1(-/+)/Pitx2(-/+) double heterozygous mice present with an extra premolar-like tooth revealing a genetic interaction between these factors. The ability of Tbx1 to repress PITX2 activation of p21 may promote cell proliferation. In addition, PITX2 regulation of p21 reveals a new role for PITX2 in repressing cell proliferation. These data demonstrate new functional mechanisms for Tbx1 in tooth morphogenesis and provide a molecular basis for craniofacial defects in DiGeorge syndrome patients. Copyright © 2010 Elsevier Inc. All rights reserved.

In Vitro Evaluation of Cell-Seeded Chitosan Films for Peripheral Nerve Tissue Engineering

PubMed Central

Wrobel, Sandra; Serra, Sofia Cristina; Ribeiro-Samy, Silvina; Sousa, Nuno; Heimann, Claudia; Barwig, Christina; Grothe, Claudia; Haastert-Talini, Kirsten

2014-01-01

Natural biomaterials have attracted an increasing interest in the field of tissue-engineered nerve grafts, representing a possible alternative to autologous nerve transplantation. With the prospect of developing a novel entubulation strategy for transected nerves with cell-seeded chitosan films, we examined the biocompatibility of such films in vitro. Different types of rat Schwann cells (SCs)—immortalized, neonatal, and adult—as well as rat bone-marrow-derived mesenchymal stromal cells (BMSCs) were analyzed with regard to their cell metabolic activity, proliferation profiles, and cell morphology after different time points of mono- and cocultures on the chitosan films. Overall the results demonstrate a good cytocompatibility of the chitosan substrate. Both cell types were viable on the biomaterial and showed different metabolic activities and proliferation behavior, indicating cell-type-specific cell–biomaterial interaction. Moreover, the cell types also displayed their typical morphology. In cocultures adult SCs used the BMSCs as a feeder layer and no negative interactions between both cell types were detected. Further, the chitosan films allow neurite outgrowth from dissociated sensory neurons, which is additionally supported on film preseeded with SC-BMSC cocultures. The presented chitosan films therefore demonstrate high potential for their use in tissue-engineered nerve grafts. PMID:24606318

Assessment of Telomere Length, Phenotype, and DNA Content

PubMed Central

Kelesidis, Theodoros; Schmid, Ingrid

2017-01-01

Telomere sequences at the end of chromosomes control somatic cell division; therefore, telomere length in a given cell population provides information about its replication potential. This unit describes a method for flow cytometric measurement of telomere length in subpopulations using fluorescence in situ hybridization of fluorescently-labeled probes (Flow-FISH) without prior cell separation. After cells are stained for surface immunofluorescence, antigen-antibody complexes are covalently cross-linked onto cell membranes before FISH with a telomere-specific probe. Cells with long telomeres are included as internal standards. Addition of a DNA dye permits exclusion of proliferating cells during data analysis. DNA ploidy measurements of cells of interest and internal standard are performed on separate aliquots in parallel to Flow-FISH. Telomere fluorescence of G0/1 cells of subpopulations and internal standards obtained from Flow-FISH are normalized for DNA ploidy, and telomere length in subsets of interest is expressed as a fraction of the internal standard telomere length. PMID:28055113

Assessment of Telomere Length, Phenotype, and DNA Content.

PubMed

Kelesidis, Theodoros; Schmid, Ingrid

2017-01-05

Telomere sequences at the end of chromosomes control somatic cell division; therefore, telomere length in a given cell population provides information about its replication potential. This unit describes a method for flow cytometric measurement of telomere length in subpopulations using fluorescence in situ hybridization of fluorescently-labeled probes (Flow-FISH) without prior cell separation. After cells are stained for surface immunofluorescence, antigen-antibody complexes are covalently cross-linked onto cell membranes before FISH with a telomere-specific probe. Cells with long telomeres are included as internal standards. Addition of a DNA dye permits exclusion of proliferating cells during data analysis. DNA ploidy measurements of cells of interest and internal standard are performed on separate aliquots in parallel to Flow-FISH. Telomere fluorescence of G 0/1 cells of subpopulations and internal standards obtained from Flow-FISH are normalized for DNA ploidy, and telomere length in subsets of interest is expressed as a fraction of the internal standard telomere length. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

p75 neurotrophin receptor is involved in proliferation of undifferentiated mouse embryonic stem cells

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

Moscatelli, Ilana; Pierantozzi, Enrico; Camaioni, Antonella

2009-11-01

Neurotrophins and their receptors are known to play a role in the proliferation and survival of many different cell types of neuronal and non-neuronal lineages. In addition, there is much evidence in the literature showing that the p75 neurotrophin receptor (p75{sup NTR}), alone or in association with members of the family of Trk receptors, is expressed in a wide variety of stem cells, although its role in such cells has not been completely elucidated. In the present work we have investigated the expression of p75{sup NTR} and Trks in totipotent and pluripotent cells, the mouse pre-implantation embryo and embryonic stemmore » and germ cells (ES and EG cells). p75{sup NTR} and TrkA can be first detected in the blastocyst from which ES cell lines are derived. Mouse ES cells retain p75{sup NTR}/TrkA expression. Nerve growth factor is the only neurotrophin able to stimulate ES cell growth in culture, without affecting the expression of stem cell markers, alkaline phosphatase, Oct4 and Nanog. Such proliferation effect was blocked by antagonizing either p75{sup NTR} or TrkA. Interestingly, immunoreactivity to anti-p75{sup NTR} antibodies is lost upon ES cell differentiation. The expression pattern of neurotrophin receptors in murine ES cells differs from human ES cells, that only express TrkB and C, and do not respond to NGF. In this paper we also show that, while primordial germ cells (PGC) do not express p75{sup NTR}, when they are made to revert to an ES-like phenotype, becoming EG cells, expression of p75{sup NTR} is turned on.« less

IFI27, a novel epidermal growth factor-stabilized protein, is functionally involved in proliferation and cell cycling of human epidermal keratinocytes.

PubMed

Hsieh, W-L; Huang, Y-H; Wang, T-M; Ming, Y-C; Tsai, C-N; Pang, J-H S

2015-04-01

IFI27 is highly expressed in psoriatic lesions but its function has not been known. The present study aimed to explore its role in proliferation of epidermal keratinocytes. IFI27 knockdown and over-expression in keratinocytes were used to compare their proliferation, by MTT assay, apoptosis (by annexin V binding) and cell cycle progression by flow cytometry. Formation of cyclin A/CDK1 complex was examined by a co-immunoprecipitaion method. Anti-proliferation effects of IFI27 were also examined in vivo by topical application of IFI27 siRNA on imiquimod-induced psoriatic lesions, in a mouse model. Epidermal growth factor was demonstrated to increase IFI27 expression by prolonging half-life of IFI27 protein. The IFI27 knockdown in keratinocytes reduced the proliferation rate, but had no effect on apoptosis nor on apoptosis-related genes. Interestingly, IFI27 knockdown resulted in S-phase arrest that was found to be associated with increased Tyr15 phosphorylation of CDK1, reduced CDC25B and reduced formation of cyclin A/CDK1 complex. In addition, IFI27 knockdown was also shown to activate p53 by Ser15 phosphorylation and increase p21 expression. Topical application of IFI27 siRNA on imiquimod-induced psoriatic lesion in a mouse model reduced epidermal thickness, formation of rete ridges and PCNA expression. Our study demonstrates for the first time, that cell function of IFI27 is involved in proliferation of skin keratinocytes both in vitro and in vivo. It suggests that IFI27 might be a suitable target for development of a novel anti-psoriasis therapy. © 2015 John Wiley & Sons Ltd.

HSPA6 augments garlic extract-induced inhibition of proliferation, migration, and invasion of bladder cancer EJ cells; Implication for cell cycle dysregulation, signaling pathway alteration, and transcription factor-associated MMP-9 regulation

PubMed Central

Hwang, Byungdoo; Noh, Dae-Hwa; Park, Sung Lyea; Kim, Won Tae; Park, Sung-Soo; Kim, Wun-Jae; Moon, Sung-Kwon

2017-01-01

Although recent studies have demonstrated the anti-tumor effects of garlic extract (GE), the exact molecular mechanism is still unclear. In this study, we investigated the molecular mechanism associated with the inhibitory action of GE against bladder cancer EJ cell responses. Treatment with GE significantly inhibited proliferation of EJ cells dose-dependently through G2/M-phase cell cycle arrest. This G2/M-phase cell cycle arrest by GE was due to the activation of ATM and CHK2, which appears to inhibit phosphorylation of Cdc25C (Ser216) and Cdc2 (Thr14/Tyr15), this in turn was accompanied by down-regulation of cyclin B1 and up-regulation of p21WAF1. Furthermore, GE treatment was also found to induce phosphorylation of MAPK (ERK1/2, p38MAPK, and JNK) and AKT. In addition, GE impeded the migration and invasion of EJ cells via inhibition of MMP-9 expression followed by decreased binding activities of AP-1, Sp-1, and NF-κB motifs. Based on microarray datasets, we selected Heat shock protein A6 (HSPA6) as the most up-regulated gene responsible for the inhibitory effects of GE. Interestingly, overexpression of HSPA6 gene resulted in an augmentation effect with GE inhibiting proliferation, migration, and invasion of EJ cells. The augmentation effect of HSPA6 was verified by enhancing the induction of G2/M-phase-mediated ATM-CHK2-Cdc25C-p21WAF1-Cdc2 cascade, phosphorylation of MAPK and AKT signaling, and suppression of transcription factor-associated MMP-9 regulation in response to GE in EJ cells. Overall, our novel results indicate that HSPA6 reinforces the GE-mediated inhibitory effects of proliferation, migration, and invasion of EJ cells and may provide a new approach for therapeutic treatment of malignancies. PMID:28187175

Bone Marrow Mesenchymal Stromal Cells Stimulate Skeletal Myoblast Proliferation through the Paracrine Release of VEGF

PubMed Central

Chellini, Flaminia; Mazzanti, Benedetta; Nistri, Silvia; Nosi, Daniele; Saccardi, Riccardo; Quercioli, Franco; Zecchi-Orlandini, Sandra; Formigli, Lucia

2012-01-01

Mesenchymal stromal cells (MSCs) are the leading cell candidates in the field of regenerative medicine. These cells have also been successfully used to improve skeletal muscle repair/regeneration; however, the mechanisms responsible for their beneficial effects remain to be clarified. On this basis, in the present study, we evaluated in a co-culture system, the ability of bone-marrow MSCs to influence C2C12 myoblast behavior and analyzed the cross-talk between the two cell types at the cellular and molecular level. We found that myoblast proliferation was greatly enhanced in the co-culture as judged by time lapse videomicroscopy, cyclin A expression and EdU incorporation. Moreover, myoblasts immunomagnetically separated from MSCs after co-culture expressed higher mRNA and protein levels of Notch-1, a key determinant of myoblast activation and proliferation, as compared with the single culture. Notch-1 intracellular domain and nuclear localization of Hes-1, a Notch-1 target gene, were also increased in the co-culture. Interestingly, the myoblastic response was mainly dependent on the paracrine release of vascular endothelial growth factor (VEGF) by MSCs. Indeed, the addition of MSC-derived conditioned medium (CM) to C2C12 cells yielded similar results as those observed in the co-culture and increased the phosphorylation and expression levels of VEGFR. The treatment with the selective pharmacological VEGFR inhibitor, KRN633, resulted in a marked attenuation of the receptor activation and concomitantly inhibited the effects of MSC-CM on C2C12 cell growth and Notch-1 signaling. In conclusion, this study provides novel evidence for a role of MSCs in stimulating myoblast cell proliferation and suggests that the functional interaction between the two cell types may be exploited for the development of new and more efficient cell-based skeletal muscle repair strategies. PMID:22815682

Developmental heterogeneity of cardiac fibroblasts does not predict pathological proliferation and activation.

PubMed

Ali, Shah R; Ranjbarvaziri, Sara; Talkhabi, Mahmood; Zhao, Peng; Subat, Ali; Hojjat, Armin; Kamran, Paniz; Müller, Antonia M S; Volz, Katharina S; Tang, Zhaoyi; Red-Horse, Kristy; Ardehali, Reza

2014-09-12

Fibrosis is mediated partly by extracellular matrix-depositing fibroblasts in the heart. Although these mesenchymal cells are reported to have multiple embryonic origins, the functional consequence of this heterogeneity is unknown. We sought to validate a panel of surface markers to prospectively identify cardiac fibroblasts. We elucidated the developmental origins of cardiac fibroblasts and characterized their corresponding phenotypes. We also determined proliferation rates of each developmental subset of fibroblasts after pressure overload injury. We showed that Thy1(+)CD45(-)CD31(-)CD11b(-)Ter119(-) cells constitute the majority of cardiac fibroblasts. We characterized these cells using flow cytometry, epifluorescence and confocal microscopy, and transcriptional profiling (using reverse transcription polymerase chain reaction and RNA-seq). We used lineage tracing, transplantation studies, and parabiosis to show that most adult cardiac fibroblasts derive from the epicardium, a minority arises from endothelial cells, and a small fraction from Pax3-expressing cells. We did not detect generation of cardiac fibroblasts by bone marrow or circulating cells. Interestingly, proliferation rates of fibroblast subsets on injury were identical, and the relative abundance of each lineage remained the same after injury. The anatomic distribution of fibroblast lineages also remained unchanged after pressure overload. Furthermore, RNA-seq analysis demonstrated that Tie2-derived and Tbx18-derived fibroblasts within each operation group exhibit similar gene expression profiles. The cellular expansion of cardiac fibroblasts after transaortic constriction surgery was not restricted to any single developmental subset. The parallel proliferation and activation of a heterogeneous population of fibroblasts on pressure overload could suggest that common signaling mechanisms stimulate their pathological response. © 2014 American Heart Association, Inc.

Dihydroartemisinin inhibits the mammalian target of rapamycin-mediated signaling pathways in tumor cells

PubMed Central

Huang, Shile

2014-01-01

Dihydroartemisinin (DHA), an antimalarial drug, has previously unrecognized anticancer activity, and is in clinical trials as a new anticancer agent for skin, lung, colon and breast cancer treatment. However, the anticancer mechanism is not well understood. Here, we show that DHA inhibited proliferation and induced apoptosis in rhabdomyosarcoma (Rh30 and RD) cells, and concurrently inhibited the signaling pathways mediated by the mammalian target of rapamycin (mTOR), a central controller for cell proliferation and survival, at concentrations (<3 μM) that are pharmacologically achievable. Of interest, in contrast to the effects of conventional mTOR inhibitors (rapalogs), DHA potently inhibited mTORC1-mediated phosphorylation of p70 S6 kinase 1 and eukaryotic initiation factor 4E binding protein 1 but did not obviously affect mTORC2-mediated phosphorylation of Akt. The results suggest that DHA may represent a novel class of mTORC1 inhibitor and may execute its anticancer activity primarily by blocking mTORC1-mediated signaling pathways in the tumor cells. PMID:23929438

Zinc enhances the number of regulatory T cells in allergen-stimulated cells from atopic subjects.

PubMed

Rosenkranz, Eva; Hilgers, Ralf-Dieter; Uciechowski, Peter; Petersen, Arnd; Plümäkers, Birgit; Rink, Lothar

2017-03-01

The trace element zinc is essential for immune function and its regulation. Since zinc deficiency and allergic hyperresponsive reactions are often accompanied, the influence of zinc on allergen-induced cell growth, CD4+ regulatory T (Treg) cell numbers and cytokine expression during allergic immune reactions was investigated. Peripheral blood mononuclear cells (PBMCs) from non-atopic and atopic subjects were treated with timothy grass allergen pre-incubated with or without zinc. Proliferation was determined by analyzing the incorporation of 3 H-thymidine. Intracellular zinc and Foxp3 levels and cell surface antigens were measured by FACS, cytokine expression by ELISA and real-time PCR. Incubation with 50 μM zinc sulfate (Zn50) enhances cytosolic zinc concentrations in CD3+ T cells. The data also reveal that the combination of Zn50 plus allergen significantly reduces PBMC proliferation of atopic subjects. Additionally, Zn50 plus allergen enhances Th1 cytokine responses shown by increased interferon (IFN)-γ/interleukin (IL)-10 ratios as well as enhanced tumor necrosis factor-α release. In response to allergen, zinc increases Treg cells and upregulates the mRNA expression of cytotoxic T-lymphocyte antigen-4 in atopic subjects. Interestingly, Zn50 alone leads to an increase of CD4+CD25high(hi)+ cells in atopic and non-atopic subjects. Zinc may regulate unwanted hyperresponsive immune reactions by suppressing proliferation through a significant shift from IL-10 to the Th1 cytokine IFN-γ, and enhanced regulatory T cell numbers. Therefore, zinc supplementation may be a promising tool for the therapy of allergies, without negatively affecting the immune system.

Permeabilization of the plasma membrane of L1210 mouse leukemia cells using lithotripter shock waves.

PubMed

Gambihler, S; Delius, M; Ellwart, J W

1994-09-01

Permeabilization of L1210 cells by lithotripter shock waves in vitro was monitored by evaluating the accumulation of fluorescein-labeled dextrans with a relative molecular mass ranging from 3,900-2,000,000. Incubation with labeled dextran alone caused a dose- and time-dependent increase in cellular fluorescence as determined by flow cytometry, with a vesicular distribution pattern in the cells consistent with endocytotic uptake. Shock wave exposure prior to incubation with labeled dextran revealed similar fluorescence intensities compared to incubation with labeled dextran alone. When cells were exposed to shock waves in the presence of labeled dextran, mean cellular fluorescence was further increased, indicating additional internalization of the probe. Confocal laser scanning microscopy confirmed intracellular fluorescence of labeled dextran with a diffuse distribution pattern. Fluorescence-activated cell sorting with subsequent determination of proliferation revealed that permeabilized cells were viable and able to proliferate. Permeabilization of the membrane of L1210 cells by shock waves in vitro allowed loading of dextrans with a relative molecular mass up to 2,000,000. Permeabilization of tumor cells by shock waves provides a useful tool for introducing molecules into cells which might be of interest for drug targeting in tumor therapy in vivo.

Inactivation of YAP oncoprotein by the Hippo pathway is involved in cell contact inhibition and tissue growth control

PubMed Central

Zhao, Bin; Wei, Xiaomu; Li, Weiquan; Udan, Ryan S.; Yang, Qian; Kim, Joungmok; Xie, Joe; Ikenoue, Tsuneo; Yu, Jindan; Li, Li; Zheng, Pan; Ye, Keqiang; Chinnaiyan, Arul; Halder, Georg; Lai, Zhi-Chun; Guan, Kun-Liang

2007-01-01

The Hippo pathway plays a key role in organ size control by regulating cell proliferation and apoptosis in Drosophila. Although recent genetic studies have shown that the Hippo pathway is regulated by the NF2 and Fat tumor suppressors, the physiological regulations of this pathway are unknown. Here we show that in mammalian cells, the transcription coactivator YAP (Yes-associated protein), is inhibited by cell density via the Hippo pathway. Phosphorylation by the Lats tumor suppressor kinase leads to cytoplasmic translocation and inactivation of the YAP oncoprotein. Furthermore, attenuation of this phosphorylation of YAP or Yorkie (Yki), the Drosophila homolog of YAP, potentiates their growth-promoting function in vivo. Moreover, YAP overexpression regulates gene expression in a manner opposite to cell density, and is able to overcome cell contact inhibition. Inhibition of YAP function restores contact inhibition in a human cancer cell line bearing deletion of Salvador (Sav), a Hippo pathway component. Interestingly, we observed that YAP protein is elevated and nuclear localized in some human liver and prostate cancers. Our observations demonstrate that YAP plays a key role in the Hippo pathway to control cell proliferation in response to cell contact. PMID:17974916

Sensitivity of tumor cells towards CIGB-300 anticancer peptide relies on its nucleolar localization.

PubMed

Perera, Yasser; Costales, Heydi C; Diaz, Yakelin; Reyes, Osvaldo; Farina, Hernan G; Mendez, Lissandra; Gómez, Roberto E; Acevedo, Boris E; Gomez, Daniel E; Alonso, Daniel F; Perea, Silvio E

2012-04-01

CIGB-300 is a novel anticancer peptide that impairs the casein kinase 2-mediated phosphorylation by direct binding to the conserved phosphoacceptor site on their substrates. Previous findings indicated that CIGB-300 inhibits tumor cell proliferation in vitro and induces tumor growth delay in vivo in cancer animal models. Interestingly, we had previously demonstrated that the putative oncogene B23/nucleophosmin (NPM) is the major intracellular target for CIGB-300 in a sensitive human lung cancer cell line. However, the ability of this peptide to target B23/NPM in cancer cells with differential CIGB-300 response phenotype remained to be determined. Interestingly, in this work, we evidenced that CIGB-300's antiproliferative activity on tumor cells strongly correlates with its nucleolar localization, the main subcellular localization of the previously identified B23/NPM target. Likewise, using CIGB-300 equipotent doses (concentration that inhibits 50% of proliferation), we demonstrated that this peptide interacts and inhibits B23/NPM phosphorylation in different cancer cell lines as evidenced by in vivo pull-down and metabolic labeling experiments. Moreover, such inhibition was followed by a fast apoptosis on CIGB-300-treated cells and also an impairment of cell cycle progression mainly after 5 h of treatment. Altogether, our data not only validates B23/NPM as a main target for CIGB-300 in cancer cells but also provides the first experimental clues to explain their differential antiproliferative response. Importantly, our findings suggest that further improvements to this cell penetrating peptide-based drug should entail its more efficient intracellular delivery at such subcellular localization. Copyright © 2012 European Peptide Society and John Wiley & Sons, Ltd.

PM2.5 promotes human bronchial smooth muscle cell migration via the sonic hedgehog signaling pathway.

PubMed

Ye, Xiuqin; Hong, Wei; Hao, Binwei; Peng, Gongyong; Huang, Lingmei; Zhao, Zhuxiang; Zhou, Yumin; Zheng, Mengning; Li, Chenglong; Liang, Chunxiao; Yi, Erkang; Pu, Jinding; Li, Bing; Ran, Pixin

2018-03-02

The contribution of airway remodeling in chronic obstructive pulmonary disease (COPD) has been well documented, with airway smooth muscle cell proliferation and migration playing a role in the remodeling process. Here, we aimed to verify the effects of fine particulate matter (PM2.5) on human bronchial smooth muscle cell (HBSMC) migration and to explore the underlying signaling pathways. HBSMC apoptosis, proliferation and migration were measured using flow cytometry, cell counting and transwell migration assays, respectively. The role of the hedgehog pathway in cell migration was assessed by western blotting to measure the expression of Sonic hedgehog (Shh), Gli1 and Snail. Furthermore, siRNA was used to knock down Gli1 or Snail expression. PM2.5 induced HBSMC apoptosis in a dose-dependent manner, although certain concentrations of PM2.5 did not induce HBSMC proliferation or apoptosis. Interestingly, cell migration was stimulated by PM2.5 doses far below those that induced apoptosis. Additional experiments revealed that these PM2.5 doses enhanced the expression of Shh, Gli1 and Snail in HBSMCs. Furthermore, PM2.5-induced cell migration and protein expression were enhanced by recombinant Shh and attenuated by cyclopamine. Similar results were obtained by knocking down Gli1 or Snail. These findings suggest that PM2.5, which may exert its effects through the Shh signaling pathway, is necessary for the migration of HBSMCs. These data define a novel role for PM2.5 in airway remodeling in COPD.

Small molecule schweinfurthins selectively inhibit cancer cell proliferation and mTOR/AKT signaling by interfering with trans-Golgi-network trafficking

PubMed Central

Bao, Xingfeng; Zheng, Wanjun; Sugi, Naoko Hata; Agarwala, Kishan L; Xu, Qunli; Wang, Zichun; Tendyke, Karen; Lee, Winnie; Parent, Lana; Li, Wei; Cheng, Hongsheng; Shen, Yongchun; Taylor, Noel; Dezso, Zoltan; Du, Hong; Kotake, Yoshihiko; Zhao, Nanding; Wang, John; Postema, Maarten; Woodall-Jappe, Mary; Takase, Yasutaka; Uenaka, Toshimitsu; Kingston, David G I; Nomoto, Kenichi

2015-01-01

Natural compound schweinfurthins are of considerable interest for novel therapy development because of their selective anti-proliferative activity against human cancer cells. We previously reported the isolation of highly active schweinfurthins E-H, and in the present study, mechanisms of the potent and selective anti-proliferation were investigated. We found that schweinfurthins preferentially inhibited the proliferation of PTEN deficient cancer cells by indirect inhibition of AKT phosphorylation. Mechanistically, schweinfurthins and their analogs arrested trans-Golgi-network trafficking, an intracellular vesicular trafficking system, resulting in the induction of endoplasmic reticulum stress and the suppression of both lipid raft-mediated PI3K activation and mTOR/RheB complex formation, which collectively led to an effective inhibition of mTOR/AKT signaling. The trans-Golgi-network traffic arresting effect of schweinfurthins was associated with their in vitro binding activity to oxysterol-binding proteins that are known to regulate intracellular vesicular trafficking. Moreover, schweinfurthins were found to be highly toxic toward PTEN-deficient B cell lymphoma cells, and displayed 2 orders of magnitude lower activity toward normal human peripheral blood mononuclear cells and primary fibroblasts in vitro. These results revealed a previously unrecognized role of schweinfurthins in regulating trans-Golgi-network trafficking, and linked mechanistically this cellular effect with mTOR/AKT signaling and with cancer cell survival and growth. Our findings suggest the schweinfurthin class of compounds as a novel approach to modulate oncogenic mTOR/AKT signaling for cancer treatment. PMID:25729885

Interaction between dendritic cells and natural killer cells during pregnancy in mice.

PubMed

Blois, Sandra M; Barrientos, Gabriela; Garcia, Mariana G; Orsal, Arif S; Tometten, Mareike; Cordo-Russo, Rosalia I; Klapp, Burghard F; Santoni, Angela; Fernández, Nelson; Terness, Peter; Arck, Petra C

2008-07-01

A complex regulation of innate and adaptive immune responses at the maternal fetal interface promotes tolerance of trophoblast cells carrying paternally derived antigens. Such regulatory functions involve uterine dendritic cells (uDC) and natural killer (uNK) cells. The existence of a NK and DC "cross talk" has been revealed in various experimental settings; its biological significance ranging from cooperative stimulation to cell lysis. Little is known about the presence or role of NK and DC cross talk at the maternal fetal interface. The present study shows that mouse NK and DC interactions are subject to modulation by trophoblast cells in vitro. This interaction promotes a tolerogenic microenvironment characterized by downregulation of the expression of activation markers on uNK cells and uDC and dominance of Th2 cytokines. NK and DC interactions would also influence uterine cell proliferation and this process would be strongly modulated by trophoblast-derived signals. Indeed; while low proliferation rates were observed upon regular coculture allowing direct contact between uterine cells and trophoblasts, incubation in a transwell culture system markedly increased uterine cell proliferation suggesting that soluble factors are key mediators in the molecular "dialog" between the mother and the conceptus during the establishment of mouse pregnancy. Our data further reveal that the regulatory functions of trophoblast cells associated with tolerance induction are impaired in high abortion murine matings. Interestingly, we observed that secretion of interleukin-12p70 by uDC is dramatically abrogated in the presence of uNK cells. Taken together, our results provide the first evidence that a delicate balance of interactions involving NK cells, DC, and trophoblasts at the mouse maternal fetal interface supports a successful pregnancy outcome.

A Whole Brain Staining, Embedding, and Clearing Pipeline for Adult Zebrafish to Visualize Cell Proliferation and Morphology in 3-Dimensions.

PubMed

Lindsey, Benjamin W; Douek, Alon M; Loosli, Felix; Kaslin, Jan

2017-01-01

The field of macro-imaging has grown considerably with the appearance of innovative clearing methods and confocal microscopes with lasers capable of penetrating increasing tissue depths. The ability to visualize and model the growth of whole organs as they develop from birth, or with manipulation, disease or injury, provides new ways of thinking about development, tissue-wide signaling, and cell-to-cell interactions. The zebrafish ( Danio rerio ) has ascended from a predominantly developmental model to a leading adult model of tissue regeneration. The unmatched neurogenic and regenerative capacity of the mature central nervous system, in particular, has received much attention, however tools to interrogate the adult brain are sparse. At present there exists no straightforward methods of visualizing changes in the whole adult brain in 3-dimensions (3-D) to examine systemic patterns of cell proliferation or cell populations of interest under physiological, injury, or diseased conditions. The method presented here is the first of its kind to offer an efficient step-by-step pipeline from intraperitoneal injections of the proliferative marker, 5-ethynyl-2'-deoxyuridine (EdU), to whole brain labeling, to a final embedded and cleared brain sample suitable for 3-D imaging using optical projection tomography (OPT). Moreover, this method allows potential for imaging GFP-reporter lines and cell-specific antibodies in the presence or absence of EdU. The small size of the adult zebrafish brain, the highly consistent degree of EdU labeling, and the use of basic clearing agents, benzyl benzoate, and benzyl alcohol, makes this method highly tractable for most laboratories interested in understanding the vertebrate central nervous system in health and disease. Post-processing of OPT-imaged adult zebrafish brains injected with EdU illustrate that proliferative patterns in EdU can readily be observed and analyzed using IMARIS and/or FIJI/IMAGEJ software. This protocol will be a valuable tool to unlock new ways of understanding systemic patterns in cell proliferation in the healthy and injured brain, brain-wide cellular interactions, stem cell niche development, and changes in brain morphology.

A Whole Brain Staining, Embedding, and Clearing Pipeline for Adult Zebrafish to Visualize Cell Proliferation and Morphology in 3-Dimensions

PubMed Central

Lindsey, Benjamin W.; Douek, Alon M.; Loosli, Felix; Kaslin, Jan

2018-01-01

The field of macro-imaging has grown considerably with the appearance of innovative clearing methods and confocal microscopes with lasers capable of penetrating increasing tissue depths. The ability to visualize and model the growth of whole organs as they develop from birth, or with manipulation, disease or injury, provides new ways of thinking about development, tissue-wide signaling, and cell-to-cell interactions. The zebrafish (Danio rerio) has ascended from a predominantly developmental model to a leading adult model of tissue regeneration. The unmatched neurogenic and regenerative capacity of the mature central nervous system, in particular, has received much attention, however tools to interrogate the adult brain are sparse. At present there exists no straightforward methods of visualizing changes in the whole adult brain in 3-dimensions (3-D) to examine systemic patterns of cell proliferation or cell populations of interest under physiological, injury, or diseased conditions. The method presented here is the first of its kind to offer an efficient step-by-step pipeline from intraperitoneal injections of the proliferative marker, 5-ethynyl-2′-deoxyuridine (EdU), to whole brain labeling, to a final embedded and cleared brain sample suitable for 3-D imaging using optical projection tomography (OPT). Moreover, this method allows potential for imaging GFP-reporter lines and cell-specific antibodies in the presence or absence of EdU. The small size of the adult zebrafish brain, the highly consistent degree of EdU labeling, and the use of basic clearing agents, benzyl benzoate, and benzyl alcohol, makes this method highly tractable for most laboratories interested in understanding the vertebrate central nervous system in health and disease. Post-processing of OPT-imaged adult zebrafish brains injected with EdU illustrate that proliferative patterns in EdU can readily be observed and analyzed using IMARIS and/or FIJI/IMAGEJ software. This protocol will be a valuable tool to unlock new ways of understanding systemic patterns in cell proliferation in the healthy and injured brain, brain-wide cellular interactions, stem cell niche development, and changes in brain morphology. PMID:29386991

Molecular and cell biological effects of 3,5,3'-triiodothyronine on progenitor cells of the enteric nervous system in vitro.

PubMed

Mohr, Roland; Neckel, Peter; Zhang, Ying; Stachon, Susanne; Nothelfer, Katharina; Schaeferhoff, Karin; Obermayr, Florian; Bonin, Michael; Just, Lothar

2013-11-01

Thyroid hormones play important roles in the development of neural cells in the central nervous system. Even minor changes to normal thyroid hormone levels affect dendritic and axonal outgrowth, sprouting and myelination and might even lead to irreversible damages such as cretinism. Despite our knowledge of the influence on the mammalian CNS, the role of thyroid hormones in the development of the enteric nervous system (ENS) still needs to be elucidated. In this study we have analyzed for the first time the influence of 3,5,3'-triiodothyronine (T3) on ENS progenitor cells using cell biological assays and a microarray technique. In our in vitro model, T3 inhibited cell proliferation and stimulated neurite outgrowth of differentiating ENS progenitor cells. Microarray analysis revealed a group of 338 genes that were regulated by T3 in differentiating enterospheres. 67 of these genes are involved in function and development of the nervous system. 14 of them belong to genes that are involved in axonal guidance or neurite outgrowth. Interestingly, T3 regulated the expression of netrin G1 and endothelin 3, two guidance molecules that are involved in human enteric dysganglionoses. The results of our study give first insights how T3 may affect the enteric nervous system. T3 is involved in proliferation and differentiation processes in enterospheres. Microarray analysis revealed several interesting gene candidates that might be involved in the observed effects on enterosphere differentiation. Future studies need to be conducted to better understand the gene to gene interactions. © 2013.

A case of hirsutism due to bilateral diffuse ovarian Leydig cell hyperplasia in a post-menopausal woman.

PubMed

Ali, F S.M.; Stanaway, S E.R.S.; Zakhour, H D.; Spearing, G; Bowen-Jones, D

2003-11-01

Hyperandrogenism in females usually results from ovarian or adrenal pathology. We present a case of virilizaton due to very rare bilateral ovarian diffuse interstitial proliferation of Leydig cells with no tumour or hilar cell hyperplasia identified. Interestingly, the case was further complicated by the finding of high levels of testosterone in one adrenal vein on selective venous sampling (SVS), resulting in an unnecessary unilateral adrenalectomy. Further sampling found high levels also in the ovarian veins, and the condition was finally cured by bilateral oophorectomy.

Neural control of colonic cell proliferation.

PubMed

Tutton, P J; Barkla, D H

1980-03-15

The mitotic rate in rat colonic crypts and in dimethylhydrazine-induced colonic carcinomas was measured using a stathmokinetic technique. In sympathectomized animals cell proliferation was retarded in the crypts but not in the tumors, whereas in animals treated with Metaraminol, a drug which releases norepinephrine from nerve terminals, crypt cell but not tumor cell proliferation was accelerated. Blockade of alpha-adrenoceptors also inhibited crypt cell proliferation. However, stimulation of beta-adrenoceptors inhibited and blockade of beta-adrenoceptors accelerated tumor cell proliferation without influencing crypt cell proliferation. Injection of either serotonin or histamine stimulated tumor but not crypt cell proliferation and blockade or serotonin receptors or histamine H2-receptors inhibited tumor cell proliferation. It is postulated that cell proliferation in the colonic crypts, like that in the jejunal crypts, is under both endocrine and autonomic neural control whereas colonic tumor cell division is subject to endocrine regulation alone.

Differences in Intracellular Fate of Two Spotted Fever Group Rickettsia in Macrophage-Like Cells.

PubMed

Curto, Pedro; Simões, Isaura; Riley, Sean P; Martinez, Juan J

2016-01-01

Spotted fever group (SFG) rickettsiae are recognized as important agents of human tick-borne diseases worldwide, such as Mediterranean spotted fever (Rickettsia conorii) and Rocky Mountain spotted fever (Rickettsia rickettsii). Recent studies in several animal models have provided evidence of non-endothelial parasitism by pathogenic SFG Rickettsia species, suggesting that the interaction of rickettsiae with cells other than the endothelium may play an important role in pathogenesis of rickettsial diseases. These studies raise the hypothesis that the role of macrophages in rickettsial pathogenesis may have been underappreciated. Herein, we evaluated the ability of two SFG rickettsial species, R. conorii (a recognized human pathogen) and Rickettsia montanensis (a non-virulent member of SFG) to proliferate in THP-1 macrophage-like cells, or within non-phagocytic cell lines. Our results demonstrate that R. conorii was able to survive and proliferate in both phagocytic and epithelial cells in vitro. In contrast, R. montanensis was able to grow in non-phagocytic cells, but was drastically compromised in the ability to proliferate within both undifferentiated and PMA-differentiated THP-1 cells. Interestingly, association assays revealed that R. montanensis was defective in binding to THP-1-derived macrophages; however, the invasion of the bacteria that are able to adhere did not appear to be affected. We have also demonstrated that R. montanensis which entered into THP-1-derived macrophages were rapidly destroyed and partially co-localized with LAMP-2 and cathepsin D, two markers of lysosomal compartments. In contrast, R. conorii was present as intact bacteria and free in the cytoplasm in both cell types. These findings suggest that a phenotypic difference between a non-pathogenic and a pathogenic SFG member lies in their respective ability to proliferate in macrophage-like cells, and may provide an explanation as to why certain SFG rickettsial species are not associated with disease in mammals.

Differences in Intracellular Fate of Two Spotted Fever Group Rickettsia in Macrophage-Like Cells

PubMed Central

Curto, Pedro; Simões, Isaura; Riley, Sean P.; Martinez, Juan J.

2016-01-01

Spotted fever group (SFG) rickettsiae are recognized as important agents of human tick-borne diseases worldwide, such as Mediterranean spotted fever (Rickettsia conorii) and Rocky Mountain spotted fever (Rickettsia rickettsii). Recent studies in several animal models have provided evidence of non-endothelial parasitism by pathogenic SFG Rickettsia species, suggesting that the interaction of rickettsiae with cells other than the endothelium may play an important role in pathogenesis of rickettsial diseases. These studies raise the hypothesis that the role of macrophages in rickettsial pathogenesis may have been underappreciated. Herein, we evaluated the ability of two SFG rickettsial species, R. conorii (a recognized human pathogen) and Rickettsia montanensis (a non-virulent member of SFG) to proliferate in THP-1 macrophage-like cells, or within non-phagocytic cell lines. Our results demonstrate that R. conorii was able to survive and proliferate in both phagocytic and epithelial cells in vitro. In contrast, R. montanensis was able to grow in non-phagocytic cells, but was drastically compromised in the ability to proliferate within both undifferentiated and PMA-differentiated THP-1 cells. Interestingly, association assays revealed that R. montanensis was defective in binding to THP-1-derived macrophages; however, the invasion of the bacteria that are able to adhere did not appear to be affected. We have also demonstrated that R. montanensis which entered into THP-1-derived macrophages were rapidly destroyed and partially co-localized with LAMP-2 and cathepsin D, two markers of lysosomal compartments. In contrast, R. conorii was present as intact bacteria and free in the cytoplasm in both cell types. These findings suggest that a phenotypic difference between a non-pathogenic and a pathogenic SFG member lies in their respective ability to proliferate in macrophage-like cells, and may provide an explanation as to why certain SFG rickettsial species are not associated with disease in mammals. PMID:27525249

Suppression of bcr-abl synthesis by siRNAs or tyrosine kinase activity by Glivec alters different oncogenes, apoptotic/antiapoptotic genes and cell proliferation factors (microarray study).

PubMed

Zhelev, Zhivko; Bakalova, Rumiana; Ohba, Hideki; Ewis, Ashraf; Ishikawa, Mitsuru; Shinohara, Yasuo; Baba, Yoshinobu

2004-07-16

Short 21-mer double-stranded/small-interfering RNAs (ds/siRNAs) were designed to target bcr-abl mRNA in chronic myelogenous leukemia. The ds/siRNAs were transfected into bcr-abl-positive K-562 (derived from blast crisis chronic myelogenous leukemia), using lipofectamine. Penetrating of ds/siRNAs into the cells was detected by fluorescent confocal microscopy, using fluorescein-labeled ds/siRNAs. The cells were treated with mix of three siRNA sequences (3 x 60 nM) during 6 days with three repetitive transfections. The siRNA-treatment was accompanied with significant reduction of bcr-abl mRNA, p210, protein tyrosine kinase activity and cell proliferation index. Treatment of cells with Glivec (during 8 days with four repetitive doses, 180 nM single dose) resulted in analogous reduction of cell proliferation activity, stronger suppression of protein tyrosine kinase activity, and very low reduction of p210. siRNA-mix and Glivec did not affect significantly the viability of normal lymphocytes. Microarray analysis of siRNA- and Glivec-treated K-562 cells demonstrated that both pathways of bcr-abl suppression were accompanied with overexpression and suppression of many different oncogenes, apoptotic/antiapoptotic and cell proliferation factors. The following genes of interest were found to decrease in relatively equal degree in both siRNA- and Glivec-treated cells: Bcd orf1 and orf2 proto-oncogene, chromatin-specific transcription elongation factor FACT 140-kDa subunit mRNA, gene encoding splicing factor SF1, and mRNA for Tec protein tyrosine kinase. siRNA-mix and Glivec provoked overexpression of the following common genes: c-jun proto-oncogene, protein kinase C-alpha, pvt-1 oncogene homologue (myc activator), interleukin-6, 1-8D gene from interferon-inducible gene family, tumor necrosis factor receptor superfamily (10b), and STAT-induced STAT inhibitor.

CDKL5, a novel MYCN-repressed gene, blocks cell cycle and promotes differentiation of neuronal cells.

PubMed

Valli, Emanuele; Trazzi, Stefania; Fuchs, Claudia; Erriquez, Daniela; Bartesaghi, Renata; Perini, Giovanni; Ciani, Elisabetta

2012-01-01

Mutations in the CDKL5 (cyclin-dependent kinase-like 5) gene are associated with a severe epileptic encephalopathy (early infantile epileptic encephalopathy type 2, EIEE2) characterized by early-onset intractable seizures, infantile spasms, severe developmental delay, intellectual disability, and Rett syndrome (RTT)-like features. Despite the clear involvement of CDKL5 mutations in intellectual disability, the function of this protein during brain development and the molecular mechanisms involved in its regulation are still unknown. Using human neuroblastoma cells as a model system we found that an increase in CDKL5 expression caused an arrest of the cell cycle in the G(0)/G(1) phases and induced cellular differentiation. Interestingly, CDKL5 expression was inhibited by MYCN, a transcription factor that promotes cell proliferation during brain development and plays a relevant role in neuroblastoma biology. Through a combination of different and complementary molecular and cellular approaches we could show that MYCN acts as a direct repressor of the CDKL5 promoter. Overall our findings unveil a functional axis between MYCN and CDKL5 governing both neuron proliferation rate and differentiation. The fact that CDKL5 is involved in the control of both neuron proliferation and differentiation may help understand the early appearance of neurological symptoms in patients with mutations in CDKL5. Copyright © 2012 Elsevier B.V. All rights reserved.

Magnetic responsive hydroxyapatite composite scaffolds construction for bone defect reparation

PubMed Central

Zeng, Xiao Bo; Hu, Hao; Xie, Li Qin; Lan, Fang; Jiang, Wen; Wu, Yao; Gu, Zhong Wei

2012-01-01

Introduction In recent years, interest in magnetic biomimetic scaffolds for tissue engineering has increased considerably. A type of magnetic scaffold composed of magnetic nanoparticles (MNPs) and hydroxyapatite (HA) for bone repair has been developed by our research group. Aim and methods In this study, to investigate the influence of the MNP content (in the scaffolds) on the cell behaviors and the interactions between the magnetic scaffold and the exterior magnetic field, a series of MNP-HA magnetic scaffolds with different MNP contents (from 0.2% to 2%) were fabricated by immersing HA scaffold into MNP colloid. ROS 17/2.8 and MC3T3-E1 cells were cultured on the scaffolds in vitro, with and without an exterior magnetic field, respectively. The cell adhesion, proliferation and differentiation were evaluated via scanning electron microscopy; confocal laser scanning microscopy; and 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), alkaline phosphatase, and bone gla protein activity tests. Results The results demonstrated the positive influence of the magnetic scaffolds on cell adhesion, proliferation, and differentiation. Further, a higher amount of MNPs on the magnetic scaffolds led to more significant stimulation. Conclusion The magnetic scaffold can respond to the exterior magnetic field and engender some synergistic effect to intensify the stimulating effect of a magnetic field to the proliferation and differentiation of cells. PMID:22848165

The Effect of Krill Oil and n-3 Polyunsaturated Fatty Acids on Human Osteosarcoma Cell Proliferation and Migration.

PubMed

Su, Xiao; Tanalgo, Philline; Bustos, Marcel; Dass, Crispin R

2018-01-01

Osteosarcoma (OS) is a neoplastic condition afflicting mostly the young, as the lesion usually occurs in areas of bone growth with tumour cells metastasising to the lungs in advanced disease. There is no real cure for the disease, with conventional drugs causing side-effects that decrease the quality of life of sufferers. Newer and safer drugs are needed, and one avenue is to use natural compounds that can stunt the growth of the tumour. In this study, two such biological entities were evaluated: krill oil and fish oil. Human OS cells were exposed to krill oil, fish oil, EPA and DHA in time-course assays lasting up to 72h. Krill oil inhibited 23, 50 and 64% of cell proliferation at 24, 48 and 72h respectively, while fish oil resulted in no significant changes although an increase was observed at 24h. Interestingly EPA and DHA promoted OS cell proliferation and migration in this neoplasia. The inhibitory effect of krill oil was comparable to 0.5 and 1µM doxorubicin, a commonly used clinical drug for OS treatment. These results indicate that krill oil may be used in combination with standard clinical practices to control primary tumour growth, and more importantly, metastasis. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

3D Non-Woven Polyvinylidene Fluoride Scaffolds: Fibre Cross Section and Texturizing Patterns Have Impact on Growth of Mesenchymal Stromal Cells

PubMed Central

Schellenberg, Anne; Ross, Robin; Abagnale, Giulio; Joussen, Sylvia; Schuster, Philipp; Arshi, Annahit; Pallua, Norbert; Jockenhoevel, Stefan; Gries, Thomas; Wagner, Wolfgang

2014-01-01

Several applications in tissue engineering require transplantation of cells embedded in appropriate biomaterial scaffolds. Such structures may consist of 3D non-woven fibrous materials whereas little is known about the impact of mesh size, pore architecture and fibre morphology on cellular behavior. In this study, we have developed polyvinylidene fluoride (PVDF) non-woven scaffolds with round, trilobal, or snowflake fibre cross section and different fibre crimp patterns (10, 16, or 28 needles per inch). Human mesenchymal stromal cells (MSCs) from adipose tissue were seeded in parallel on these scaffolds and their growth was compared. Initial cell adhesion during the seeding procedure was higher on non-wovens with round fibres than on those with snowflake or trilobal cross sections. All PVDF non-woven fabrics facilitated cell growth over a time course of 15 days. Interestingly, proliferation was significantly higher on non-wovens with round or trilobal fibres as compared to those with snowflake profile. Furthermore, proliferation increased in a wider, less dense network. Scanning electron microscopy (SEM) revealed that the MSCs aligned along the fibres and formed cellular layers spanning over the pores. 3D PVDF non-woven scaffolds support growth of MSCs, however fibre morphology and mesh size are relevant: proliferation is enhanced by round fibre cross sections and in rather wide-meshed scaffolds. PMID:24728045

The Cytosolic pH of Individual Saccharomyces cerevisiae Cells Is a Key Factor in Acetic Acid Tolerance.

PubMed

Fernández-Niño, Miguel; Marquina, Maribel; Swinnen, Steve; Rodríguez-Porrata, Boris; Nevoigt, Elke; Ariño, Joaquín

2015-11-01

It was shown recently that individual cells of an isogenic Saccharomyces cerevisiae population show variability in acetic acid tolerance, and this variability affects the quantitative manifestation of the trait at the population level. In the current study, we investigated whether cell-to-cell variability in acetic acid tolerance could be explained by the observed differences in the cytosolic pHs of individual cells immediately before exposure to the acid. Results obtained with cells of the strain CEN.PK113-7D in synthetic medium containing 96 mM acetic acid (pH 4.5) showed a direct correlation between the initial cytosolic pH and the cytosolic pH drop after exposure to the acid. Moreover, only cells with a low initial cytosolic pH, which experienced a less severe drop in cytosolic pH, were able to proliferate. A similar correlation between initial cytosolic pH and cytosolic pH drop was also observed in the more acid-tolerant strain MUCL 11987-9. Interestingly, a fraction of cells in the MUCL 11987-9 population showed initial cytosolic pH values below the minimal cytosolic pH detected in cells of the strain CEN.PK113-7D; consequently, these cells experienced less severe drops in cytosolic pH. Although this might explain in part the difference between the two strains with regard to the number of cells that resumed proliferation, it was observed that all cells from strain MUCL 11987-9 were able to proliferate, independently of their initial cytosolic pH. Therefore, other factors must also be involved in the greater ability of MUCL 11987-9 cells to endure strong drops in cytosolic pH. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Differential role of Sloan–Kettering Institute (Ski) protein in Nodal and transforming growth factor-beta (TGF-β)-induced Smad signaling in prostate cancer cells

PubMed Central

Khan, Shafiq A.

2012-01-01

Transforming growth factor-beta (TGF-β) signaling pathways contain both tumor suppressor and tumor promoting activities. We have demonstrated that Nodal, another member of the TGF-β superfamily, and its receptors are expressed in prostate cancer cells. Nodal and TGF-β exerted similar biological effects on prostate cells; both inhibited proliferation in WPE, RWPE1 and DU145 cells, whereas neither had any effect on the proliferation of LNCaP or PC3 cells. Interestingly, Nodal and TGF-β induced migration in PC3 cells, but not in DU145 cells. TGF-β induced predominantly phosphorylation of Smad3, whereas Nodal induced phosphorylation of only Smad2. We also determined the expression and differential role of Ski, a corepressor of Smad2/3, in Nodal and TGF-β signaling in prostate cancer cells. Similar levels of Ski mRNA were found in several established prostate cell lines; however, high levels of Ski protein were only detected in prostate cancer cells and prostate cancer tissue samples. Exogenous Nodal and TGF-β had no effects on Ski mRNA levels. On the other hand, TGF-β induced a rapid degradation of Ski protein mediated by the proteasomal pathway, whereas Nodal had no effect on Ski protein. Reduced Ski levels correlated with increased basal and TGF-β-induced Smad2/3 phosphorylation. Knockdown of endogenous Ski reduced proliferation in DU145 cells and enhanced migration of PC3 cells. We conclude that high levels of Ski expression in prostate cancer cells may be responsible for repression of TGF-β and Smad3 signaling, but Ski protein levels do not influence Nodal and Smad2 signaling. PMID:22843506

The Cytosolic pH of Individual Saccharomyces cerevisiae Cells Is a Key Factor in Acetic Acid Tolerance

PubMed Central

Fernández-Niño, Miguel; Marquina, Maribel; Swinnen, Steve; Rodríguez-Porrata, Boris

2015-01-01

It was shown recently that individual cells of an isogenic Saccharomyces cerevisiae population show variability in acetic acid tolerance, and this variability affects the quantitative manifestation of the trait at the population level. In the current study, we investigated whether cell-to-cell variability in acetic acid tolerance could be explained by the observed differences in the cytosolic pHs of individual cells immediately before exposure to the acid. Results obtained with cells of the strain CEN.PK113-7D in synthetic medium containing 96 mM acetic acid (pH 4.5) showed a direct correlation between the initial cytosolic pH and the cytosolic pH drop after exposure to the acid. Moreover, only cells with a low initial cytosolic pH, which experienced a less severe drop in cytosolic pH, were able to proliferate. A similar correlation between initial cytosolic pH and cytosolic pH drop was also observed in the more acid-tolerant strain MUCL 11987-9. Interestingly, a fraction of cells in the MUCL 11987-9 population showed initial cytosolic pH values below the minimal cytosolic pH detected in cells of the strain CEN.PK113-7D; consequently, these cells experienced less severe drops in cytosolic pH. Although this might explain in part the difference between the two strains with regard to the number of cells that resumed proliferation, it was observed that all cells from strain MUCL 11987-9 were able to proliferate, independently of their initial cytosolic pH. Therefore, other factors must also be involved in the greater ability of MUCL 11987-9 cells to endure strong drops in cytosolic pH. PMID:26341199

Wnt and Notch Pathways Have Interrelated Opposing Roles on Prostate Progenitor Cell Proliferation and Differentiation

PubMed Central

Shahi, Payam; Seethammagari, Mamatha R.; Valdez, Joseph M.; Xin, Li; Spencer, David M.

2011-01-01

Tissue stem cells are capable of both self-renewal and differentiation to maintain a constant stem cell population and give rise to the plurality of cells within a tissue. Wnt signaling has been previously identified as a key mediator for the maintenance of tissue stem cells; however, possible cross-regulation with other developmentally critical signaling pathways involved in adult tissue homeostasis, such as Notch, is not well understood. By using an in vitro prostate stem cell colony (“prostasphere”) formation assay and in vivo prostate reconstitution experiments, we demonstrate that Wnt pathway induction on Sca-1+ CD49f+ basal/stem cells (B/SCs) promotes expansion of the basal epithelial compartment with noticeable increases in “triple positive” (cytokeratin [CK] 5+, CK8+, p63+) prostate progenitor cells, concomitant with upregulation of known Wnt target genes involved in cell-cycle induction. Moreover, Wnt induction affects expression of epithelial-to-mesenchymal transition signature genes, suggesting a possible mechanism for priming B/SC to act as potential tumor-initiating cells. Interestingly, induction of Wnt signaling in B/SCs results in downregulation of Notch1 transcripts, consistent with its postulated antiproliferative role in prostate cells. In contrast, induction of Notch signaling in prostate progenitors inhibits their proliferation and disrupts prostasphere formation. In vivo prostate reconstitution assays further demonstrate that induction of Notch in B/SCs disrupts proper acini formation in cells expressing the activated Notch1 allele, Notch-1 intracellular domain. These data emphasize the importance of Wnt/Notch cross-regulation in adult stem cell biology and suggest that Wnt signaling controls the proliferation and/or maintenance of epithelial progenitors via modulation of Notch signaling. PMID:21308863

Chemical characterization, antioxidant, immune-regulating and anticancer activities of a novel bioactive polysaccharide from Chenopodium quinoa seeds.

PubMed

Hu, Yichen; Zhang, Jinming; Zou, Liang; Fu, Chaomei; Li, Peng; Zhao, Gang

2017-06-01

Chenopodium quinoa, a promising nutraceutical cereal, has attracted increasing research interest, yet its polysaccharides remains to get few systematic studies. In this study, we employed orthogonal experimental design to optimize the ultrasound-assisted extraction process for highest yield of C. quinoa polysaccharides. A novel C. quinoa polysaccharide (CQP) fraction with high content and low molecular weight (8852Da) was subsequently purified by column chromatography, constituted by galacturonic acid and glucose monosaccharides. The purified CQP exhibited significantly antioxidant effect against DPPH + and ABTS + , with even higher efficiency than some other reported polysaccharides. Moreover, CQP could promote the RAW264.7 macrophage proliferation, while suppress the nitri oxide production on inflammatory RAW264.7 macrophage in a dose- and time-dependent manner. In view of the pathological correlation of free radical, inflammation and carcinogenesis, the anticancer effect of CQP was further investigated on human liver cancer SMMC 7721 and breast cancer MCF-7 cells. Interestingly, CQP displayed cytotoxicity against cancer cells, while none proliferation inhibition on normal cells. These results suggest that the bioactive polysaccharide from C. quinoa provided the promising potential as a natural antioxidant, immune-regulating and anticancer candidate for food and even drug application. Copyright © 2017 Elsevier B.V. All rights reserved.

Malat1 as an evolutionarily conserved lncRNA, plays a positive role in regulating proliferation and maintaining undifferentiated status of early-stage hematopoietic cells.

PubMed

Ma, Xian-Yong; Wang, Jian-Hui; Wang, Jing-Lan; Ma, Charles X; Wang, Xiao-Chun; Liu, Feng-Song

2015-09-03

The metastasis-associated lung adenocarcinoma transcription 1 (Malat1) is a highly conserved long non-coding RNA (lncRNA) gene. Previous studies showed that Malat1 is abundantly expressed in many tissues and involves in promoting tumor growth and metastasis by modulating gene expression and target protein activities. However, little is known about the biological function and regulation mechanism of Malat1 in normal cell proliferation. In this study we conformed that Malat1 is highly conserved across vast evolutionary distances amongst 20 species of mammals in terms of sequence, and found that mouse Malat1 expresses in tissues of liver, kidney, lung, heart, testis, spleen and brain, but not in skeletal muscle. After treating erythroid myeloid lymphoid (EML) cells with All-trans Retinoic Acid (ATRA), we investigated the expression and regulation of Malat1 during hematopoietic differentiation, the results showed that ATRA significantly down regulates Malat1 expression during the differentiation of EML cells. Mouse LRH (Lin-Rhodamine(low) Hoechst(low)) cells that represent the early-stage progenitor cells show a high level of Malat1 expression, while LRB (Lin - Hoechst(Low) Rhodamine(Bright)) cells that represent the late-stage progenitor cells had no detectable expression of Malat1. Knockdown experiment showed that depletion of Malat1 inhibits the EML cell proliferation. Along with the down regulation of Malat1, the tumor suppressor gene p53 was up regulated during the differentiation. Interestingly, we found two p53 binding motifs with help of bioinformatic tools, and the following chromatin immunoprecipitation (ChIP) test conformed that p53 acts as a transcription repressor that binds to Malat1's promoter. Furthermore, we testified that p53 over expression in EML cells causes down regulation of Malat1. In summary, this study indicates Malat1 plays a critical role in maintaining the proliferation potential of early-stage hematopoietic cells. In addition to its biological function, the study also uncovers the regulation pattern of Malat1 expression mediated by p53 in hematopoietic differentiation. Our research shed a light on exploring the Malat1 biological role including therapeutic significance to inhibit the proliferation potential of malignant cells.

Microenvironmental cues enhance mesenchymal stem cell-mediated immunomodulation and regulatory T-cell expansion.

PubMed

Kadle, Rohini L; Abdou, Salma A; Villarreal-Ponce, Alvaro P; Soares, Marc A; Sultan, Darren L; David, Joshua A; Massie, Jonathan; Rifkin, William J; Rabbani, Piul; Ceradini, Daniel J

2018-01-01

Mesenchymal stem cells (MSCs) are known to both have powerful immunosuppressive properties and promote allograft tolerance. Determining the environmental oxygen tension and inflammatory conditions under which MSCs are optimally primed for this immunosuppressive function is essential to their utilization in promoting graft tolerance. Of particular interest is the mechanisms governing the interaction between MSCs and regulatory T cells (Tregs), which is relatively unknown. We performed our experiments utilizing rat bone marrow derived MSCs. We observed that priming MSCs in hypoxia promotes maintenance of stem-like characteristics, with greater expression of typical MSC cell-surface markers, increased proliferation, and maintenance of differentiation potential. Addition of autologous MSCs to CD4+/allogeneic endothelial cell (EC) co-culture increases regulatory T cell (Treg) proliferation, which is further enhanced when MSCs are primed in hypoxia. Furthermore, MSC-mediated Treg expansion does not require direct cell-cell contact. The expression of indolamine 2,3-dioxygenase, a mediator of MSC immunomodulation, increases when MSCs are primed in hypoxia, and inhibition of IDO significantly decreases the expansion of Tregs. Priming with inflammatory cytokines IFNγ and TNFα increases also expression of markers associated with MSC immunomodulatory function, but decreases MSC proliferation. The expression of IDO also increases when MSCs are primed with inflammatory cytokines. However, there is no increase in Treg expansion when MSCs are primed with IFNγ, suggesting an alternate mechanism for inflammatory-stimulated MSC immunomodulation. Overall, these results suggest that MSCs primed in hypoxia or inflammatory conditions are optimally primed for immunosuppressive function. These results provide a clearer picture of how to enhance MSC immunomodulation for clinical use.

Microenvironmental cues enhance mesenchymal stem cell-mediated immunomodulation and regulatory T-cell expansion

PubMed Central

Abdou, Salma A.; Villarreal-Ponce, Alvaro P.; Soares, Marc A.; Sultan, Darren L.; David, Joshua A.; Massie, Jonathan; Rabbani, Piul

2018-01-01

Mesenchymal stem cells (MSCs) are known to both have powerful immunosuppressive properties and promote allograft tolerance. Determining the environmental oxygen tension and inflammatory conditions under which MSCs are optimally primed for this immunosuppressive function is essential to their utilization in promoting graft tolerance. Of particular interest is the mechanisms governing the interaction between MSCs and regulatory T cells (Tregs), which is relatively unknown. We performed our experiments utilizing rat bone marrow derived MSCs. We observed that priming MSCs in hypoxia promotes maintenance of stem-like characteristics, with greater expression of typical MSC cell-surface markers, increased proliferation, and maintenance of differentiation potential. Addition of autologous MSCs to CD4+/allogeneic endothelial cell (EC) co-culture increases regulatory T cell (Treg) proliferation, which is further enhanced when MSCs are primed in hypoxia. Furthermore, MSC-mediated Treg expansion does not require direct cell-cell contact. The expression of indolamine 2,3-dioxygenase, a mediator of MSC immunomodulation, increases when MSCs are primed in hypoxia, and inhibition of IDO significantly decreases the expansion of Tregs. Priming with inflammatory cytokines IFNγ and TNFα increases also expression of markers associated with MSC immunomodulatory function, but decreases MSC proliferation. The expression of IDO also increases when MSCs are primed with inflammatory cytokines. However, there is no increase in Treg expansion when MSCs are primed with IFNγ, suggesting an alternate mechanism for inflammatory-stimulated MSC immunomodulation. Overall, these results suggest that MSCs primed in hypoxia or inflammatory conditions are optimally primed for immunosuppressive function. These results provide a clearer picture of how to enhance MSC immunomodulation for clinical use. PMID:29513756

Isolation and characterization of naturally occurring subclasses of human peripheral blood T cells with regulatory functions.

PubMed

Strelkauskas, A J; Schauf, V; Wilson, B S; Chess, L; Schlossman, S F

1978-04-01

By utilizing naturally occurring autoimmune antibodies from patients with juvenile rheumatoid arthritis, we have isolated and functionally characterized two unique subpopulations of T cells. JRA+ T cells, i.e., those identified by sera from these patients, react poorly in response to allogeneic cells, respond to Con A but not PHA, and do not help in the synthesis and secretion of Ig by B cells. In contrast, JRA- T cells, i.e., those not identified by sera from these patients, respond very well to allogeneic cells, proliferate well in response to PHA but not Con A, and more interestingly, can greatly enhance the secretion of Ig by B cells.

Toll-like receptor expression and function differ between splenic marginal zone B cell lymphoma and splenic diffuse red pulp B cell lymphoma

PubMed Central

Verney, Aurélie; Traverse-Glehen, Alexandra; Callet-Bauchu, Evelyne; Jallades, Laurent; Magaud, Jean-Pierre; Salles, Gilles; Genestier, Laurent; Baseggio, Lucile

2018-01-01

In splenic marginal zone lymphoma (SMZL), specific and functional Toll-like Receptor (TLR) patterns have been recently described, suggesting their involvement in tumoral proliferation. Splenic diffuse red pulp lymphoma with villous lymphocytes (SDRPL) is close to but distinct from SMZL, justifying here the comparison of TLR patterns and functionality in both entities. Distinct TLR profiles were observed in both lymphoma subtypes. SDRPL B cells showed higher expression of TLR7 and to a lesser degree TLR9, in comparison to SMZL B cells. In both entities, TLR7 and TLR9 pathways appeared functional, as shown by IL-6 production upon TLR7 and TLR9 agonists stimulations. Interestingly, circulating SDRPL, but not SMZL B cells, constitutively expressed CD86. In addition, stimulation with both TLR7 and TLR9 agonists significantly increased CD80 expression in circulating SDRPL but not SMZL B cells. Finally, TLR7 and TLR9 stimulations had no impact on proliferation and apoptosis of SMZL or SDRPL B cells. In conclusion, SMZL and SDRPL may derive from different splenic memory B cells with specific immunological features that can be used as diagnosis markers in the peripheral blood.

Establishment of a long-term primary culture of striatal neurons.

PubMed

Sebben, M; Gabrion, J; Manzoni, O; Sladeczek, F; Gril, C; Bockaert, J; Dumuis, A

1990-03-01

A new method of obtaining long-term primary cultures (lasting more than 8 weeks) of striatal neurons is described in this paper. The originality of the method consists of: (1) starting the culture for 3 days in a serum-free medium which allows attachment and neurite proliferation of neurons as well as the death of non-neuronal cells (mainly consisting of astrocytes); (2) introducing a limited amount of fetal calf serum (FCS) (2-5%) after 3 days in vitro (3 DIV), which likely provides optimal neuronal survival and attachment factors, and a limited amount of astrocyte proliferating factors. The period of introduction of serum, as well as the amount of serum introduced are critical factors. By phase contrast and transmission electron microscopy, we observed that neurons continued to develop neurite extensions, synaptic vesicles and synapse formations up to 50 DIV. Neuronal membranes, and synaptic contacts were particularly healthy up to 50 DIV. Interestingly, the number of astrocytes was constant between 30-50 DIV and limited to about 10%. We therefore obtained an equilibrium between neuronal and astrocyte differentiation and proliferation. It is likely that the small population of astrocytes, plus the low percentage of FCS added, provide essential factors for neuronal survival and differentiation, whereas a high density of differentiated neurons inhibited astrocyte cell proliferation. The clear-cut stability of these neuronal cultures goes in parallel with the stability of the pharmacological responses studied here: the coupling of carbachol and quisqualate receptors with the inositol phosphate production system. The culture method described here could be of particular interest to pursue biochemical, pharmacological and biological studies on neurons as well as on reciprocal interactions between neurons and astrocytes.

Deletion of H-Ras decreases renal fibrosis and myofibroblast activation following ureteral obstruction in mice.

PubMed

Grande, M Teresa; Fuentes-Calvo, Isabel; Arévalo, Miguel; Heredia, Fabiana; Santos, Eugenio; Martínez-Salgado, Carlos; Rodríguez-Puyol, Diego; Nieto, M Angela; López-Novoa, José M

2010-03-01

Tubulointerstitial fibrosis is characterized by the presence of myofibroblasts that contribute to extracellular matrix accumulation. These cells may originate from resident fibroblasts, bone-marrow-derived cells, or renal epithelial cells converting to a mesenchymal phenotype. Ras GTPases are activated during renal fibrosis and play crucial roles in regulating both cell proliferation and TGF-beta-induced epithelial-mesenchymal transition. Here we set out to assess the contribution of Ras to experimental renal fibrosis using the well-established model of unilateral ureteral obstruction. Fifteen days after obstruction, both fibroblast proliferation and inducers of epithelial-mesenchymal transition were lower in obstructed kidneys of H-ras knockout mice and in fibroblast cell lines derived from these mice. Interestingly, fibronectin, collagen I accumulation, overall interstitial fibrosis, and the myofibroblast population were also lower in the knockout than in the wild-type mice. As expected, we found lower levels of activated Akt in the kidneys and cultured fibroblasts of the knockout. Whether Ras inhibition will turn out to prevent progression of renal fibrosis will require more direct studies.

Prohibitin 2 Regulates the Proliferation and Lineage-Specific Differentiation of Mouse Embryonic Stem Cells in Mitochondria

PubMed Central

Komazaki, Shinji; Enomoto, Kei; Seki, Yasuhiro; Wang, Ying Ying; Ishigaki, Yohei; Ninomiya, Naoto; Noguchi, Taka-aki K.; Kokubu, Yuko; Ohnishi, Keigoh; Nakajima, Yoshiro; Kato, Kaoru; Intoh, Atsushi; Takada, Hitomi; Yamakawa, Norio; Wang, Pi-Chao; Asashima, Makoto; Kurisaki, Akira

2014-01-01

Background The pluripotent state of embryonic stem (ES) cells is controlled by a network of specific transcription factors. Recent studies also suggested the significant contribution of mitochondria on the regulation of pluripotent stem cells. However, the molecules involved in these regulations are still unknown. Methodology/Principal Findings In this study, we found that prohibitin 2 (PHB2), a pleiotrophic factor mainly localized in mitochondria, is a crucial regulatory factor for the homeostasis and differentiation of ES cells. PHB2 was highly expressed in undifferentiated mouse ES cells, and the expression was decreased during the differentiation of ES cells. Knockdown of PHB2 induced significant apoptosis in pluripotent ES cells, whereas enhanced expression of PHB2 contributed to the proliferation of ES cells. However, enhanced expression of PHB2 strongly inhibited ES cell differentiation into neuronal and endodermal cells. Interestingly, only PHB2 with intact mitochondrial targeting signal showed these specific effects on ES cells. Moreover, overexpression of PHB2 enhanced the processing of a dynamin-like GTPase (OPA1) that regulates mitochondrial fusion and cristae remodeling, which could induce partial dysfunction of mitochondria. Conclusions/Significance Our results suggest that PHB2 is a crucial mitochondrial regulator for homeostasis and lineage-specific differentiation of ES cells. PMID:24709813

Antisense inhibition of hyaluronan synthase-2 in human osteosarcoma cells inhibits hyaluronan retention and tumorigenicity

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

Nishida, Yoshihiro; Knudson, Warren; Knudson, Cheryl B.

2005-07-01

Osteosarcoma is a common malignant bone tumor associated with childhood and adolescence. The results of numerous studies have suggested that hyaluronan plays an important role in regulating the aggressive behavior of various types of cancer cells. However, no studies have addressed hyaluronan with respect to osteosarcomas. In this investigation, the mRNA expression copy number of three mammalian hyaluronan synthases (HAS) was determined using competitive RT-PCR in the osteoblastic osteosarcoma cell line, MG-63. MG-63 are highly malignant osteosarcoma cells with an abundant hyaluronan-rich matrix. The results demonstrated that HAS-2 is the predominant HAS in MG-63. Accumulation of intracellular hyaluronan increased inmore » association with the proliferative phase of these cells. The selective inhibition of HAS-2 mRNA in MG-63 cells by antisense phosphorothioate oligonucleotides resulted in reduced hyaluronan accumulation by these cells. As expected, the reduction in hyaluronan disrupted the assembly of cell-associated matrices. However, of most interest, coincident with the reduction in hyaluronan, there was a substantial decrease in cell proliferation, a decrease in cell motility and a decrease in cell invasiveness. These data suggest that hyaluronan synthesized by HAS-2 in MG-63 plays a crucial role in osteosarcoma cell proliferation, motility, and invasion.« less

Induction of intestinalization in human esophageal keratinocytes is a multistep process.

PubMed

Kong, Jianping; Nakagawa, Hiroshi; Isariyawongse, Brandon K; Funakoshi, Shinsuke; Silberg, Debra G; Rustgi, Anil K; Lynch, John P

2009-01-01

Barrett's esophagus (BE) is the replacement of normal squamous esophageal mucosa with an intestinalized columnar epithelium. The molecular mechanisms underlying its development are not understood. Cdx2 is an intestine-specific transcription factor that is ectopically expressed in BE, but its role in this process is unclear. Herein, we describe a novel cell culture model for BE. Retroviral-mediated Cdx2 expression in immortalized human esophageal keratinocytes [EPC-human telomerase reverse transcriptase (hTERT)] could transiently be established but not maintained and was associated with a reduction in cell proliferation. Coexpression of cyclin D1, but not a dominant-negative p53, rescued proliferation in the Cdx2-expressing cells. Cdx2 expression in the EPC-hTERT.D1 cells decreased cell proliferation but did not induce intestinalization. We investigated for other treatments to enhance intestinalization and found that acidic culture conditions uniformly killed EPC-hTERT.D1.Cdx2 cells. However, treatment with 5-aza-2-deoxycytidine (5-AzaC) to demethylate epigenetically silenced genes did appear to be tolerated. Multiple Cdx2 target genes, markers of intestinal differentiation and markers of BE, were induced by this 5-AzaC treatment. More interestingly, the expression level of several of these genes was enhanced only in the EPC-hTERT.D1-Cdx2 cells treated with 5-AzaC. Two of these, SLC26a3/DRA (downregulated in adenoma) and Na+/H+ exchanger 2 (NHE2), were not previously known to be elevated in BE; however, we confirmed their elevation in BE tissue samples. 5-AzaC treatment also induced cell senescence, even at low doses. We conclude that ectopic proliferation signals, alterations in epigenetic gene regulation and the inhibition of tumor suppressor mechanisms are required for Cdx2-mediated intestinalization of human esophageal keratinocytes in BE.

Induction of intestinalization in human esophageal keratinocytes is a multistep process

PubMed Central

Kong, Jianping; Nakagawa, Hiroshi; Isariyawongse, Brandon K.; Funakoshi, Shinsuke; Silberg, Debra G.; Rustgi, Anil K.; Lynch, John P.

2009-01-01

Barrett's esophagus (BE) is the replacement of normal squamous esophageal mucosa with an intestinalized columnar epithelium. The molecular mechanisms underlying its development are not understood. Cdx2 is an intestine-specific transcription factor that is ectopically expressed in BE, but its role in this process is unclear. Herein, we describe a novel cell culture model for BE. Retroviral-mediated Cdx2 expression in immortalized human esophageal keratinocytes [EPC-human telomerase reverse transcriptase (hTERT)] could transiently be established but not maintained and was associated with a reduction in cell proliferation. Coexpression of cyclin D1, but not a dominant-negative p53, rescued proliferation in the Cdx2-expressing cells. Cdx2 expression in the EPC-hTERT.D1 cells decreased cell proliferation but did not induce intestinalization. We investigated for other treatments to enhance intestinalization and found that acidic culture conditions uniformly killed EPC-hTERT.D1.Cdx2 cells. However, treatment with 5-aza-2-deoxycytidine (5-AzaC) to demethylate epigenetically silenced genes did appear to be tolerated. Multiple Cdx2 target genes, markers of intestinal differentiation and markers of BE, were induced by this 5-AzaC treatment. More interestingly, the expression level of several of these genes was enhanced only in the EPC-hTERT.D1-Cdx2 cells treated with 5-AzaC. Two of these, SLC26a3/DRA (downregulated in adenoma) and Na+/H+ exchanger 2 (NHE2), were not previously known to be elevated in BE; however, we confirmed their elevation in BE tissue samples. 5-AzaC treatment also induced cell senescence, even at low doses. We conclude that ectopic proliferation signals, alterations in epigenetic gene regulation and the inhibition of tumor suppressor mechanisms are required for Cdx2-mediated intestinalization of human esophageal keratinocytes in BE. PMID:18845559

Targeting of X-linked inhibitor of apoptosis protein and PI3-kinase/AKT signaling by embelin suppresses growth of leukemic cells

PubMed Central

Prabhu, Kirti S.; Siveen, Kodappully S.; Kuttikrishnan, Shilpa; Iskandarani, Ahmad; Tsakou, Magdalini; Achkar, Iman W.; Therachiyil, Lubna; Krishnankutty, Roopesh; Parray, Aijaz; Kulinski, Michal; Merhi, Maysaloun; Dermime, Said; Mohammad, Ramzi M.

2017-01-01

The X-linked inhibitor of apoptosis (XIAP) is a viable molecular target for anticancer drugs that overcome apoptosis-resistance of malignant cells. XIAP is an inhibitor of apoptosis, mediating through its association with BIR3 domain of caspase 9. Embelin, a quinone derivative isolated from the Embelia ribes plant, has been shown to exhibit chemopreventive, anti-inflammatory, and apoptotic activities via inhibiting XIAP activity. In this study, we found that embelin causes a dose-dependent suppression of proliferation in leukemic cell lines K562 and U937. Embelin mediated inhibition of proliferation correlates with induction of apoptosis. Furthermore, embelin treatment causes loss of mitochondrial membrane potential and release of cytochrome c, resulting in subsequent activation of caspase-3 followed by polyadenosin-5’-diphosphate-ribose polymerase (PARP) cleavage. In addition, embelin treatment of leukemic cells results in a decrease of constitutive phosphorylations/activation level of AKT and downregulation of XIAP. Gene silencing of XIAP and AKT expression showed a link between XIAP expression and activated AKT in leukemic cells. Interestingly, targeting of XIAP and PI3-kinase/AKT signaling augmented inhibition of proliferation and induction of apoptosis in leukemic cells. Altogether these findings raise the possibility that embelin alone or in combination with inhibitors of PI3-kinase/AKT pathway may have therapeutic usage in leukemia and possibly other malignancies with up-regulated XIAP pathway. PMID:28704451

Biodiesel from soybean promotes cell proliferation in vitro.

PubMed

Gioda, Adriana; Rodríguez-Cotto, Rosa I; Amaral, Beatriz Silva; Encarnación-Medina, Jarline; Ortiz-Martínez, Mario G; Jiménez-Vélez, Braulio D

2016-08-01

Toxicological responses of exhaust emissions of biodiesel are different due to variation in methods of generation and the tested biological models. A chemical profile was generated using ICP-MS and GC-MS for the biodiesel samples obtained in Brazil. A cytotoxicity assay and cytokine secretion experiments were evaluated in human bronchial epithelial cells (BEAS-2B). Cells were exposed to polar (acetone) and nonpolar (hexane) extracts from particles obtained from fuel exhaust: fossil diesel (B5), pure soybean biodiesel (B100), soybean biodiesel with additive (B100A) and ethanol additive (EtOH). Biodiesel and its additives exhibited higher organic and inorganic constituents on particles when compared to B5. The biodiesel extracts did not exert any toxic effect at concentrations 10, 25, 50, 75, and 100μgmL(-1). In fact quite the opposite, a cell proliferation effect induced by the B100 and B100A extracts is reported. A small increase in concentrations of inflammatory mediators (Interleukin-6, IL-6; and Interleukin-8, IL-8) in the medium of biodiesel-treated cells was observed, however, no statistical difference was found. An interesting finding indicates that the presence of metals in the nonpolar (hexane) fraction of biodiesel fuel (B100) represses cytokine release in lung cells. This was revealed by the use of the metal chelator. Results suggest that metals associated with biodiesel's organic constituents might play a significant role in molecular mechanisms associated to cellular proliferation and immune responses. Published by Elsevier Ltd.

Biodiesel from Soybean Promotes Cell Proliferation in Vitro

PubMed Central

Gioda, Adriana; Rodríguez-Cotto, Rosa I.; Amaral, Beatriz Silva; Encarnación-Medina, Jarline; Ortiz-Martínez, Mario G.; Jiménez-Vélez, Braulio D.

2016-01-01

Toxicological responses of exhaust emissions of biodiesel are different due to variation in methods of generation and the tested biological models. A chemical profile was generated using ICP-MS and GC-MS for the biodiesel samples obtained in Brazil. A cytotoxicity assay and cytokine secretion experiments were evaluated in human bronchial epithelial cells (BEAS-2B). Cells were exposed to polar (acetone) and nonpolar (hexane) extracts from particles obtained from fuel exhaust: fossil diesel (B5), pure soybean biodiesel (B100), soybean biodiesel with additive (B100A) and ethanol additive (EtOH). Biodiesel and its additives exhibited higher organic and inorganic constituents on particles when compared to B5. The biodiesel extracts did not exert any toxic effect at concentrations 10, 25, 50, 75, and 100 μg mL -1. In fact quite the opposite, a cell proliferation effect induced by the B100 and B100A extracts is reported. A small increase in concentrations of inflammatory mediators (Interleukin-6, IL-6; and Interleukin-8, IL-8) in the medium of biodiesel-treated cells was observed, however, no statistical difference was found. An interesting finding indicates that the presence of metals in the nonpolar (hexane) fraction of biodiesel fuel (B100) represses cytokine release in lung cells. This was revealed by the use of the metal chelator. Results suggest that metals associated with biodiesel’s organic constituents might play a significant role in molecular mechanisms associated to cellular proliferation and immune responses. PMID:27179667

Differential expression of FGF receptors and of myogenic regulatory factors in primary cultures of satellite cells originating from fast (EDL) and slow (Soleus) twitch rat muscles.

PubMed

Martelly, I; Soulet, L; Bonnavaud, S; Cebrian, J; Gautron, J; Barritault, D

2000-11-01

In the rat, the fast and slow twitch muscles respectively Extensor digitorum longus (EDL) and Soleus present differential characteristics during regeneration. This suggests that their satellite cells responsible for muscle growth and repair represent distinct cellular populations. We have previously shown that satellite cells dissociated from Soleus and grown in vitro proliferate more readily than those isolated from EDL muscle. Fibroblast growth factors (FGFs) are known as regulators of myoblast proliferation and several studies have revealed a relationship between the response of myoblasts to FGF and the expression of myogenic regulatory factors (MRF) of the MyoD family by myoblasts. Therefore, we presently examined the possibility that the satellite cells isolated from EDL and Soleus muscles differ in the expression of FGF receptors (FGF-R) and of MRF expression. FGF-R1 and -R4 were strongly expressed in proliferating cultures whereas FGF-R2 and R3 were not detected in these cultures. In differentiating cultures, only -R1 was present in EDL satellite cells while FGF-R4 was also still expressed in Soleus cells. Interestingly, the unconventional receptor for FGF called cystein rich FGF receptor (CFR), of yet unknown function, was mainly detected in EDL satellite cell cultures. Soleus and EDL satellite cell cultures also differed in the expression MRFs. These results are consistent with the notion that satellite cells from fast and slow twitch muscles belong to different types of myogenic cells and suggest that satellite cells might play distinct roles in the formation and diversification of fast and slow fibres.

Oligomeric proanthocyanidin complexes (OPC) exert anti-proliferative and pro-apoptotic effects on prostate cancer cells.

PubMed

Neuwirt, Hannes; Arias, Mercedes Cedeno; Puhr, Martin; Hobisch, Alfred; Culig, Zoran

2008-11-01

Oligomeric proanthocyanidin complexes (OPC) are extracted from grape seeds or maritime pine bark and have been used for enhancement of capillary stability and lymphatic drainage. Since a role for OPC in cancer prevention was postulated, we asked whether they have an effect on prostate cancer cells. Cell proliferation was determined by (3)H-thymidine assay and cell cycle status was analyzed on a flow cytometer. Expression of regulators of proliferation and apoptosis was determined by Western blot. We found that androgen-responsive cells LNCaP are more sensitive to OPC in terms of inhibition of proliferation in comparison to androgen receptor-negative PC3 or DU145 cells. Treatment with OPC resulted in a decrease in the percentage of LNCaP cells in the S phase and an increase in the percentage of cells in sub G1 phase. The anti-proliferative and pro-apoptotic effect of OPC in the LNCaP cell line was associated with down-regulation of expression of the androgen receptor. Interestingly, similar regulatory effects of OPC, such as inhibition of expression of cyclin-dependent kinases and cyclins and stimulation of tumor suppressors p21 and p27, were seen in LNCaP and PC3 cells. Favorable changes in the Bcl-2/Bax ratio were observed in LNCaP and PC3 cells after the treatment with OPC. OPC caused an increase of phosphorylated mitogen-activated protein kinase p44 and p42, thus suggesting induction of cellular differentiation. We conclude that OPC is a candidate that fulfills criteria for chemopreventive strategies in prostate cancer that might be established in following in vivo studies. (c) 2008 Wiley-Liss, Inc.

Involvement of Heterogeneous Ribonucleoprotein F in the Regulation of Cell Proliferation via the Mammalian Target of Rapamycin/S6 Kinase 2 Pathway

PubMed Central

Goh, Eddy T. H.; Pardo, Olivier E.; Michael, Nicholas; Niewiarowski, Andrew; Totty, Nick; Volkova, Dariya; Tsaneva, Irina R.; Seckl, Michael J.; Gout, Ivan

2010-01-01

The S6 kinases (S6Ks) have been linked to a number of cellular processes, including translation, insulin metabolism, cell survival, and RNA splicing. Signaling via the phosphotidylinositol 3-kinase and mammalian target of rapamycin (mTOR) pathways is critical in regulating the activity and subcellular localization of S6Ks. To date, nuclear functions of both S6K isoforms, S6K1 and S6K2, are not well understood. To better understand S6K nuclear roles, we employed affinity purification of S6Ks from nuclear preparations followed by mass spectrometry analysis for the identification of novel binding partners. In this study, we report that in contrast to S6K1, the S6K2 isoform specifically associates with a number of RNA-binding proteins, including heterogeneous ribonucleoproteins (hnRNPs). We focused on studying the mechanism and physiological relevance of the S6K2 interaction with hnRNP F/H. Interestingly, the S6K2-hnRNP F/H interaction was not affected by mitogenic stimulation, whereas mTOR binding to hnRNP F/H was induced by serum stimulation. In addition, we define a new role of hnRNP F in driving cell proliferation, which could be partially attenuated by rapamycin treatment. S6K2-driven cell proliferation, on the other hand, could be blocked by small interfering RNA-mediated down-regulation of hnRNP F. These results demonstrate that the specific interaction between mTOR and S6K2 with hnRNPs is implicated in the regulation of cell proliferation. PMID:20308064

Role of NADPH Oxidase-4 in Human Endothelial Progenitor Cells

PubMed Central

Hakami, Nora Y.; Ranjan, Amaresh K.; Hardikar, Anandwardhan A.; Dusting, Greg J.; Peshavariya, Hitesh M.

2017-01-01

Introduction: Endothelial progenitor cells (EPCs) display a unique ability to promote angiogenesis and restore endothelial function in injured blood vessels. NADPH oxidase 4 (NOX4)-derived hydrogen peroxide (H2O2) serves as a signaling molecule and promotes endothelial cell proliferation and migration as well as protecting against cell death. However, the role of NOX4 in EPC function is not completely understood. Methods: EPCs were isolated from human saphenous vein and mammary artery discarded during bypass surgery. NOX4 gene and protein expression in EPCs were measured by real time-PCR and Western blot analysis respectively. NOX4 gene expression was inhibited using an adenoviral vector expressing human NOX4 shRNA (Ad-NOX4i). H2O2 production was measured by Amplex red assay. EPC migration was evaluated using a transwell migration assay. EPC proliferation and viability were measured using trypan blue counts. Results: Inhibition of NOX4 using Ad-NOX4i reduced Nox4 gene and protein expression as well as H2O2 formation in EPCs. Inhibition of NOX4-derived H2O2 decreased both proliferation and migration of EPCs. Interestingly, pro-inflammatory cytokine tumor necrosis factor alpha (TNFα) decreased NOX4 expression and reduced survival of EPCs. However, the survival of EPCs was further diminished by TNF-α in NOX4-knockdown cells, suggesting that NOX4 has a protective role in EPCs. Conclusion: These findings suggest that NOX4-type NADPH oxidase is important for proliferation and migration functions of EPCs and protects against pro-inflammatory cytokine induced EPC death. These properties of NOX4 may facilitate the efficient function of EPCs which is vital for successful neovascularization. PMID:28386230

TNF{alpha} acting on TNFR1 promotes breast cancer growth via p42/P44 MAPK, JNK, Akt and NF-{kappa}B-dependent pathways

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

Rivas, Martin A.; Carnevale, Romina P.; Proietti, Cecilia J.

2008-02-01

Tumor necrosis factor {alpha} (TNF{alpha}) enhances proliferation of chemically-induced mammary tumors and of T47D human cell line through not fully understood pathways. Here, we explored the intracellular signaling pathways triggered by TNF{alpha}, the participation of TNF{alpha} receptor (TNFR) 1 and TNFR2 and the molecular mechanism leading to breast cancer growth. We demonstrate that TNF{alpha} induced proliferation of C4HD murine mammary tumor cells and of T47D cells through the activation of p42/p44 MAPK, JNK, PI3-K/Akt pathways and nuclear factor-kappaB (NF-{kappa}B) transcriptional activation. A TNF{alpha}-specific mutein selectively binding to TNFR1 induced p42/p44 MAPK, JNK, Akt activation, NF-{kappa}B transcriptional activation and cell proliferation,more » just like wild-type TNF{alpha}, while a mutein selective for TNFR2 induced only p42/p44 MAPK activation. Interestingly, blockage of TNFR1 or TNFR2 with specific antibodies was enough to impair TNF{alpha} signaling and biological effect. Moreover, in vivo TNF{alpha} administration supported C4HD tumor growth. We also demonstrated, for the first time, that injection of a selective inhibitor of NF-{kappa}B activity, Bay 11-7082, resulted in regression of TNF{alpha}-promoted tumor. Bay 11-7082 blocked TNF{alpha} capacity to induce cell proliferation and up-regulation of cyclin D1 and of Bcl-x{sub L}in vivo and in vitro. Our results reveal evidence for TNF{alpha} as a breast tumor promoter, and provide novel data for a future therapeutic approach using TNF{alpha} antagonists and NF-{kappa}B pharmacological inhibitors in established breast cancer treatment.« less

Enhancing the reliability and throughput of neurosphere culture on hydrogel microwell arrays.

PubMed

Cordey, Myriam; Limacher, Monika; Kobel, Stefan; Taylor, Verdon; Lutolf, Matthias P

2008-10-01

The neurosphere assay is the standard retrospective assay to test the self-renewal capability and multipotency of neural stem cells (NSCs) in vitro. However, it has recently become clear that not all neurospheres are derived from a NSC and that on conventional cell culture substrates, neurosphere motility may cause frequent neurosphere "merging" [Nat Methods 2006;3:801-806; Stem Cells 2007;25:871-874]. Combining biomimetic hydrogel matrix technology with microengineering, we developed a microwell array platform on which NSC fate and neurosphere formation can be unequivocally attributed to a single founding cell. Using time-lapse microscopy and retrospective immunostaining, the fate of several hundred single NSCs was quantified. Compared with conventional neurosphere culture methods on plastic dishes, we detected a more than 100% increase in single NSC viability on soft hydrogels. Effective confinement of single proliferating cells to microwells led to neurosphere formation of vastly different sizes, a high percentage of which showed stem cell phenotypes after one week in culture. The reliability and increased throughput of this platform should help to better elucidate the function of sphere-forming stem/progenitor cells independent of their proliferation dynamics. Disclosure of potential conflicts of interest is found at the end of this article.

HMGA1 silencing reduces stemness and temozolomide resistance in glioblastoma stem cells.

PubMed

Colamaio, Marianna; Tosti, Nadia; Puca, Francesca; Mari, Alessia; Gattordo, Rosaria; Kuzay, Yalçın; Federico, Antonella; Pepe, Anna; Sarnataro, Daniela; Ragozzino, Elvira; Raia, Maddalena; Hirata, Hidenari; Gemei, Marica; Mimori, Koshi; Del Vecchio, Luigi; Battista, Sabrina; Fusco, Alfredo

2016-10-01

Glioblastoma multiforme (GBM) develops from a small subpopulation of stem-like cells, which are endowed with the ability to self-renew, proliferate and give rise to progeny of multiple neuroepithelial lineages. These cells are resistant to conventional chemo- and radiotherapy and are hence also responsible for tumor recurrence. HMGA1 overexpression has been shown to correlate with proliferation, invasion, and angiogenesis of GBMs and to affect self-renewal of cancer stem cells from colon cancer. The role of HMGA1 in GBM tumor stem cells is not completely understood. We have investigated the role of HMGA1 in brain tumor stem cell (BTSC) self-renewal, stemness and resistance to temozolomide by shRNA- mediated HMGA1 silencing. We first report that HMGA1 is overexpressed in a subset of BTSC lines from human GBMs. Then, we show that HMGA1 knockdown reduces self-renewal, sphere forming efficiency and stemness, and sensitizes BTSCs to temozolomide. Interestingly, HMGA1 silencing also leads to reduced tumor initiation ability in vivo. These results demonstrate a pivotal role of HMGA1 in cancer stem cell gliomagenesis and endorse HMGA1 as a suitable target for CSC-specific GBM therapy.

Cytokine Production but Lack of Proliferation in Peripheral Blood Mononuclear Cells from Chronic Chagas' Disease Cardiomyopathy Patients in Response to T. cruzi Ribosomal P Proteins

PubMed Central

Longhi, Silvia A.; Atienza, Augusto; Perez Prados, Graciela; Buying, Alcinette; Balouz, Virginia; Buscaglia, Carlos A.; Santos, Radleigh; Tasso, Laura M.; Bonato, Ricardo; Chiale, Pablo; Gómez, Karina A.

2014-01-01

Background Trypanosoma cruzi ribosomal P proteins, P2β and P0, induce high levels of antibodies in patients with chronic Chagas' disease Cardiomyopathy (CCC). It is well known that these antibodies alter the beating rate of cardiomyocytes and provoke apoptosis by their interaction with β1-adrenergic and M2-muscarinic cardiac receptors. Based on these findings, we decided to study the cellular immune response to these proteins in CCC patients compared to non-infected individuals. Methodology/Principal findings We evaluated proliferation, presence of surface activation markers and cytokine production in peripheral blood mononuclear cells (PBMC) stimulated with P2β, the C-terminal portion of P0 (CP0) proteins and T. cruzi lysate from CCC patients predominantly infected with TcVI lineage. PBMC from CCC patients cultured with P2β or CP0 proteins, failed to proliferate and express CD25 and HLA-DR on T cell populations. However, multiplex cytokine assays showed that these antigens triggered higher secretion of IL-10, TNF-α and GM-CSF by PBMC as well as both CD4+ and CD8+ T cells subsets of CCC subjects. Upon T. cruzi lysate stimulation, PBMC from CCC patients not only proliferated but also became activated within the context of Th1 response. Interestingly, T. cruzi lysate was also able to induce the secretion of GM-CSF by CD4+ or CD8+ T cells. Conclusions/Significance Our results showed that although the lack of PBMC proliferation in CCC patients in response to ribosomal P proteins, the detection of IL-10, TNF-α and GM-CSF suggests that specific T cells could have both immunoregulatory and pro-inflammatory potential, which might modulate the immune response in Chagas' disease. Furthermore, it was possible to demonstrate for the first time that GM-CSF was produced by PBMC of CCC patients in response not only to recombinant ribosomal P proteins but also to parasite lysate, suggesting the value of this cytokine to evaluate T cells responses in T. cruzi infection. PMID:24901991

Modulation of telomerase activity in fish muscle by biological and environmental factors.

PubMed

Peterson, Drew Ryan; Mok, Helen Oi Lam; Au, Doris Wai Ting

2015-12-01

Telomerase expression has long been linked to promotion of tumor growth and cell proliferation in mammals. Interestingly, telomerase activity (TA) has been detected in skeletal muscle for a variety of fish species. Despite this being a unique feature in fish, very few studies have investigated the potential role of TA in muscle. The present study was set to prove the concepts that muscle telomerase in fish is related to body growth, and more specifically, to muscle cell proliferation and apoptosis in vivo. Moreover, muscle TA can be influenced by biotic factors and modulated by environmental stress. Using three fish species, mangrove red snapper (Lutjanus argentimaculatus), orange-spotted grouper (Epinephelus coioides), and marine medaka (Oryzias melastigma), the present work reports for the first time that fish muscle TA was sensitive to the environmental stresses of starvation, foodborne exposure to benzo[a]pyrene, and hypoxia. In marine medaka, muscle TA was coupled with fish growth during early life stages. Upon sexual maturation, muscle TA was confounded by sex (female>male). Muscle TA was significantly correlated with telomerase reverse transcriptase (TERT) protein expression (Pearson correlation r=0.892; p≤0.05), which was coupled with proliferating cell nuclear antigen (PCNA) cell proliferation, but not associated with apoptosis (omBax/omBcl2 ratio) in muscle tissue. The results reported here have bridged the knowledge gap between the existence and function of telomerase in fish muscle. The underlying regulatory mechanisms of muscle TA in fish warrant further exploration for comparison with telomerase regulation in mammals. Copyright © 2015 Elsevier Inc. All rights reserved.

[Current topics on cancer biology and research strategies for anti-cancer traditional Chinese medicine].

PubMed

Chen, Xiu-ping; Tang, Zheng-hai; Shi, Zhe; Lu, Jin-jian; Su, Huan-xing; Chen, Xin; Wang, Yi-tao

2015-09-01

Cancer, an abnormal cell proliferation resulted from multi-factors,has the highest morbidity and mortality among all the serious diseases. Considerable progress has been made in cancer biology in recent years. Tumor immunology, cancer stem cells (CSCs), autophagy, and epithelial-mesenchymal transition (EMT) have become hot topics of interests in this area. Detailed dissection of these biological processes will provide novel directions, targets, and strategies for the pharmacological evaluation, mechanism elucidation, and new drug development of traditional Chinese medicine.

Cell proliferation within small intestinal crypts is the principal driving force for cell migration on villi

PubMed Central

Parker, Aimee; Maclaren, Oliver J.; Fletcher, Alexander G.; Muraro, Daniele; Kreuzaler, Peter A.; Byrne, Helen M.; Maini, Philip K.; Watson, Alastair J. M.; Pin, Carmen

2017-01-01

The functional integrity of the intestinal epithelial barrier relies on tight coordination of cell proliferation and migration, with failure to regulate these processes resulting in disease. It is not known whether cell proliferation is sufficient to drive epithelial cell migration during homoeostatic turnover of the epithelium. Nor is it known precisely how villus cell migration is affected when proliferation is perturbed. Some reports suggest that proliferation and migration may not be related while other studies support a direct relationship. We used established cell-tracking methods based on thymine analog cell labeling and developed tailored mathematical models to quantify cell proliferation and migration under normal conditions and when proliferation is reduced and when it is temporarily halted. We found that epithelial cell migration velocities along the villi are coupled to cell proliferation rates within the crypts in all conditions. Furthermore, halting and resuming proliferation results in the synchronized response of cell migration on the villi. We conclude that cell proliferation within the crypt is the primary force that drives cell migration along the villus. This methodology can be applied to interrogate intestinal epithelial dynamics and characterize situations in which processes involved in cell turnover become uncoupled, including pharmacological treatments and disease models.—Parker, A., Maclaren, O. J., Fletcher, A. G., Muraro, D., Kreuzaler, P. A., Byrne, H. M., Maini, P. K., Watson, A. J. M., Pin, C. Cell proliferation within small intestinal crypts is the principal driving force for cell migration on villi. PMID:27811059

Selection of G1-PABA as a GPER1 ligand compared to phenol red via a ligand-based virtual screening coupled to molecular dynamics simulations and its anti-proliferative effects on breast cancer cells.

PubMed

Jose, Correa-Basurto; Trujillo-Ferrara, Jose G; Irene, Mendoza-Lujambio; Alfonso, Duenas-Gonzalez; Alma, Chavez-Blanco; Marlet, Martinez-Archundia; Bello, M; Ruben, Garcia Sanchez Jose; Jonathan, Fragoso-Vazquez Manuel; David, Mendez-Luna; Berenice, Prestegui-Martel; Alberto, Martinez-Munoz

2018-05-10

Recent reports have demonstrated the role of the G protein-coupled estrogen receptor (GPER1) on the growth and proliferation of breast cancer cells. The coupling of GPER1 to estrogen, tamoxifen or fulvestrant triggers cellular signaling pathways (PI3K and ERK) related to cell proliferation. In an effort to develop new therapeutic strategies against breast cancer, we performed an in silico study to explore the binding pose of a set of designed G15 and G1 analogue compounds, including phenol red. First, we included a carboxyl group instead of the acetyl group from G1 to form amides with several moieties to increase the affinity for GPER1. Then, all the target compounds were submitted to an in silico ADMET study. Then, the ligands were coupled to GPER1 using ligand-based virtual screening to finally achieve molecular dynamics simulations of the best molecule on GPER1, as well as of phenol red, to explore its recognition properties. According to the in silico ADMET and docking studies, the best molecule was named G1-PABA ((3aS,4R,9bR)-4-(6-bromobenzo[d][1,3]dioxol-5-yl)-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinoline-8-carboxylic acid). It was synthesized and assayed in vitro in breast cancer (MCF-7 and MDA-MB-231) and normal (MCF-10A) cell lines. Experimental assays showed that the target compound was able to decrease cell proliferation, showing IC50 values of 15.93 M, 52.92 M and 32.45 M in the MCF-7, MDA-MB-231 and MCF-10A cell lines, respectively, after 72 h of treatment. Interestingly, the target compound showed better IC50 values without phenol red, suggesting that phenol red could interfere with the G1-PABA action at GPER, which is present in MCF-7 cells according to PCR studies and explains the cell proliferation effects. In conclusion, a concentration-dependent inhibition of cell proliferation occurred with G1-PABA in the assayed cell lines and could be due to its action on GPER1. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

The potential for chemical mixtures from the environment to enable the cancer hallmark of sustained proliferative signalling

PubMed Central

Engström, Wilhelm; Darbre, Philippa; Eriksson, Staffan; Gulliver, Linda; Hultman, Tove; Karamouzis, Michalis V.; Klaunig, James E.; Mehta, Rekha; Moorwood, Kim; Sanderson, Thomas; Sone, Hideko; Vadgama, Pankaj; Wagemaker, Gerard; Ward, Andrew; Singh, Neetu; Al-Mulla, Fahd; Al-Temaimi, Rabeah; Amedei, Amedeo; Colacci, Anna Maria; Vaccari, Monica; Mondello, Chiara; Scovassi, A. Ivana; Raju, Jayadev; Hamid, Roslida A.; Memeo, Lorenzo; Forte, Stefano; Roy, Rabindra; Woodrick, Jordan; Salem, Hosni K.; Ryan, Elizabeth; Brown, Dustin G.; Bisson, William H.

2015-01-01

The aim of this work is to review current knowledge relating the established cancer hallmark, sustained cell proliferation to the existence of chemicals present as low dose mixtures in the environment. Normal cell proliferation is under tight control, i.e. cells respond to a signal to proliferate, and although most cells continue to proliferate into adult life, the multiplication ceases once the stimulatory signal disappears or if the cells are exposed to growth inhibitory signals. Under such circumstances, normal cells remain quiescent until they are stimulated to resume further proliferation. In contrast, tumour cells are unable to halt proliferation, either when subjected to growth inhibitory signals or in the absence of growth stimulatory signals. Environmental chemicals with carcinogenic potential may cause sustained cell proliferation by interfering with some cell proliferation control mechanisms committing cells to an indefinite proliferative span. PMID:26106143

Impact of PTEN on the expression of insulin-like growth factors (IGFs) and IGF-binding proteins in human gastric adenocarcinoma cells

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

Yi, Ho-Keun; Kim, Sun-Young; Hwang, Pyoung-Han

2005-05-13

PTEN is a tumor suppressor gene that is frequently mutated or deleted in a variety of human cancers including human gastric cancer. PTEN functions primarily as a lipid phosphatase and plays a key role in the regulation of the PI3 kinase/Akt pathway, thereby modulating cell proliferation and cell survival. On the other hand, the IGF system plays an important role in cell proliferation and cell survival via the PI3 kinase/Akt and MAP kinase pathways in many cancer cells. To characterize the impact of PTEN on the IGF-IGFR-IGFBP axis in gastric cancer, we overexpressed PTEN using an adenovirus gene transfer systemmore » in human gastric adenocarcinoma cells, SNU-484 and SNU-663, which lack PTEN. Overexpression of PTEN inhibited serum-induced as well as IGF-I-induced cell proliferation as compared to control cells. PTEN overexpression resulted in a significant decrease in the expression of IGF-I, -II, and IGF-IR. Interestingly, amongst the six IGFBPs, only IGFBP-3 was upregulated by PTEN, whereas IGFBP-4 and -6 were reduced. The IGFBP-3 promoter activity assay and Western immunoblotting demonstrate that PTEN regulates IGFBP-3 at the transcriptional level. In addition, the PI3 kinase inhibitor, LY294002, upregulates IGFBP-3 expression but downregulates IGF-I and IGF-II, indicating that PTEN controls IGFBP-3 and IGFs by an Akt-dependent pathway. These findings suggest that PTEN may inhibit antiapoptotic IGF actions not only by blocking the IGF-IGFR-induced Akt activity, but also by regulating expression of components of the IGF system, in particular, upregulation of IGFBP-3, which is known to exert antiproliferative effects through IGF-dependent and IGF-independent mechanisms in cancer cells.« less

DKK3 Overexpression Increases the Malignant Properties of Head and Neck Squamous Cell Carcinoma Cells.

PubMed

Katase, Naoki; Nishimatsu, Shin-Ichiro; Yamauchi, Akira; Yamamura, Masahiro; Terada, Kumiko; Itadani, Masumi; Okada, Naoko; Hassan, Nur Mohammad Monsur; Nagatsuka, Hitoshi; Ikeda, Tohru; Nohno, Tsutomu; Fujita, Shuichi

2018-01-19

DKK3, a member of the dickkopf Wnt signaling pathway inhibitor family, is believed to be a tumor suppressor because of its reduced expression in cancer cells. However, our previous studies have revealed that DKK3 expression is predominantly observed in head and neck/oral squamous cell carcinoma (HNSCC/OSCC). Interestingly, HNSCC/OSCC patients with DKK3 expression showed a high rate of metastasis and poorer survival, and siRNA-mediated knockdown of DKK3 in HNSCC-derived cancer cell lines resulted in reduced cellular migration and invasion. From these data, it was hypothesized that DKK3 might exert an oncogenic function specific to HNSCC. In the present research, the DKK3 overexpression model was established, and its influences were investigated, together with molecular mechanism studies. The DKK3 expression profile in cancer cell lines was investigated, including HNSCC/OSCC, esophageal, gastric, colorectal, pancreatic, prostatic, and lung cancers. DKK3 overexpression was performed in HNSCC-derived cells by transfection of expression plasmid. The effects of DKK3 overexpression were assessed on cellular proliferation, migration, invasion, and in vivo tumor growth. The molecular mechanism of DKK3 overexpression was investigated by Western blotting and microarray analysis. DKK3 overexpression significantly elevated cellular proliferation, migration, and invasion, as well as increased mRNA expression of cyclin D1 and c-myc. However, reporter assays did not show TCF/LEF activation, suggesting that the increased malignant property of cancer cells was not driven by the Wnt/β-catenin pathway. For the investigation of the pathways/molecules in DKK3-mediated signals, the Western blot analyses revealed that phosphorylation of Akt (S473) and c-Jun (Ser63) was elevated. The application of a PI3K kinase inhibitor, LY294002, on HSC-3 DKK3 cells significantly decreased tumor cell proliferation, migration, and invasion. From these results, we demonstrated that DKK3 might contribute to cellular proliferation, invasion, migration, and tumor cell survival in HNSCC cells through a mechanism other than the canonical Wnt signaling pathway, which might be attributed to PI3K-Akt signaling.

The role of prospero homeobox 1 (PROX1) expression in follicular thyroid carcinoma cells

PubMed Central

Rudzinska, Magdalena; Ledwon, Joanna K.; Gawel, Damian; Sikorska, Justyna; Czarnocka, Barbara

2017-01-01

The prospero homeobox 1 (Prox1) transcription factor is a key player during embryogenesis and lymphangiogenesis. Altered Prox1 expression has been found in a variety of human cancers, including papillary thyroid carcinoma (PTC). Interestingly, Prox1 may exert tumor suppressive or tumor promoting effect, depending on the tissue context. In this study, we have analyzed Prox1 expression in normal and malignant human thyroid carcinoma cell lines. Moreover, we determined the effect of Prox1 silencing and overexpression on the cellular processes associated with the metastatic potential of tumor cells: proliferation, migration, invasion, apoptosis and anchorage-independent growth, in the follicular thyroid carcinoma (FTC) FTC-133 cell line. We found that Prox1 expression was significantly higher in FTC-derived cells than in PTC-derived cells and normal thyroid, and it was associated with the PI3K/Akt signaling pathway. In the FTC-133 cells, it was associated with cell invasive potential, motility and wound closure capacities, but not with proliferation or apoptosis. Modifying Prox1 expression also induced substantial changes in the cytoskeleton structure and cell morphology. In conclusion, we have shown that Prox1 plays an important role in the development of FTC and that its suppression prevents, whereas its overexpression promotes, the malignant behavior of thyroid follicular cancer cells. PMID:29371975

BNIP3 contributes to the glutamine-driven aggressive behavior of melanoma cells.

PubMed

Vara-Perez, Monica; Maes, Hannelore; Van Dingenen, Sarah; Agostinis, Patrizia

2018-06-01

Aerobic glycolysis (Warburg effect) is used by cancer cells to fuel tumor growth. Interestingly, metastatic melanoma cells rely on glutaminolysis rather than aerobic glycolysis for their bioenergetic needs through the tricarboxylic acid cycle. Here, we compared the effects of glucose or glutamine on melanoma cell proliferation, migration and oxidative phosphorylation in vitro. We found that glutamine-driven melanoma cell's aggressive traits positively correlated with increased expression of HIF1α and its pro-autophagic target BNIP3. BNIP3 silencing reduced glutamine-mediated effects on melanoma cell growth, migration and bioenergetics. Hence, BNIP3 is a vital component of the mitochondria quality control required for glutamine-driven melanoma aggressiveness.

Sex Differences in Maturation of Human Embryonic Stem Cell-Derived β Cells in Mice.

PubMed

Saber, Nelly; Bruin, Jennifer E; O'Dwyer, Shannon; Schuster, Hellen; Rezania, Alireza; Kieffer, Timothy J

2018-04-01

Pancreatic progenitors derived from human embryonic stem cells (hESCs) are now in clinical trials for insulin replacement in patients with type 1 diabetes. Animal studies indicate that pancreatic progenitor cells can mature into a mixed population of endocrine cells, including glucose-responsive β cells several months after implantion. However, it remains unclear how conditions in the recipient may influence the maturation and ultimately the function of these hESC-derived cells. Here, we investigated the effects of (1) pregnancy on the maturation of human stage 4 (S4) pancreatic progenitor cells and (2) the impact of host sex on both S4 cells and more mature stage 7 (S7) pancreatic endocrine cells implanted under the kidney capsule of immunodeficient SCID-beige mice. Pregnancy led to increased proliferation of endogenous pancreatic β cells, but did not appear to affect proliferation or maturation of S4 cells at midgestation. Interestingly, S4 and S7 cells both acquired glucose-stimulated C-peptide secretion in females before males. Moreover, S4 cells lowered fasting blood glucose levels in females sooner than in males, whereas the responses with S7 cells were similar. These data indicate that the host sex may impact the maturation of hESC-derived cells in vivo and that this effect can be minimized by more advanced differentiation of the cells before implantation.

Phytoplankton IF-FISH: Species-specific labeling of cellular proteins by immunofluorescence (IF) with simultaneous species identification by fluorescence immunohybridization (FISH).

PubMed

Meek, Megan E; Van Dolah, Frances M

2016-05-01

Phytoplankton rarely occur as unialgal populations. Therefore, to study species-specific protein expression, indicative of physiological status in natural populations, methods are needed that will both assay for a protein of interest and identify the species expressing it. Here we describe a protocol for IF-FISH, a dual labeling procedure using immunofluorescence (IF) labeling of a protein of interest followed by fluorescence in situ hybridization (FISH) to identify the species expressing that protein. The protocol was developed to monitor expression of the cell cycle marker proliferating cell nuclear antigen (PCNA) in the red tide dinoflagellate, Karenia brevis, using a large subunit (LSU) rRNA probe to identify K. brevis in a mixed population of morphologically similar Karenia species. We present this protocol as proof of concept that IF-FISH can be successfully applied to phytoplankton cells. This method is widely applicable for the analysis of single-cell protein expression of any protein of interest within phytoplankton communities. Copyright © 2016 Elsevier B.V. All rights reserved.

Relative impact of uniaxial alignment vs. form-induced stress on differentiation of human adipose derived stem cells

PubMed Central

Huang, Samuel; Li, Julie Yi-Shuan; Chien, Shu; Zhang, Kang; Chen, Shaochen

2013-01-01

ADSCs are a great cell source for tissue engineering and regenerative medicine. However, the development of methods to appropriately manipulate these cells in vitro remains a challenge. Here the proliferation and differentiation of ADSCs on microfabricated surfaces with varying geometries were investigated. To create the patterned substrates, a maskless biofabrication method was developed based on dynamic optical projection stereolithography. Proliferation and early differentiation of ADSCs were compared across three distinct multicellular patterns, namely stripes (ST), symmetric fork (SF), and asymmetric fork (AF). The ST pattern was designed for uniaxial cell alignment while the SF and AF pattern were designed with altered cell directionality to different extents. The SF and AF patterns generated similar levels of regional peak stress, which were both significantly higher than those within the ST pattern. No significant difference in ADSC proliferation was observed among the three patterns. In comparison to the ST pattern, higher peak stress levels of the SF and AF patterns were associated with up-regulation of the chondrogenic and osteogenic markers SOX9 and RUNX2. Interestingly, uniaxial cell alignment in the ST pattern seemed to increase the expression of SM22α and smooth muscle α-actin, suggesting an early smooth muscle lineage progression. These results indicate that geometric cues that promote uniaxial alignment might be more potent for myogenesis than those with increased peak stress. Overall, the use of these patterned geometric cues for modulating cell alignment and form-induced stress can serve as a powerful and versatile technique towards controlling differentiation in ADSCs. PMID:24060419

Fibroblast growth factor receptor 2 (FGFR2) is required for corneal epithelial cell proliferation and differentiation during embryonic development.

PubMed

Zhang, Jinglin; Upadhya, Dinesh; Lu, Lin; Reneker, Lixing W

2015-01-01

Fibroblast growth factors (FGFs) play important roles in many aspects of embryonic development. During eye development, the lens and corneal epithelium are derived from the same surface ectodermal tissue. FGF receptor (FGFR)-signaling is essential for lens cell differentiation and survival, but its role in corneal development has not been fully investigated. In this study, we examined the corneal defects in Fgfr2 conditional knockout mice in which Cre expression is activated at lens induction stage by Pax6 P0 promoter. The cornea in LeCre, Fgfr2(loxP/loxP) mice (referred as Fgfr2(CKO)) was analyzed to assess changes in cell proliferation, differentiation and survival. We found that Fgfr2(CKO) cornea was much thinner in epithelial and stromal layer when compared to WT cornea. At embryonic day 12.5-13.5 (E12.5-13.5) shortly after the lens vesicle detaches from the overlying surface ectoderm, cell proliferation (judged by labeling indices of Ki-67, BrdU and phospho-histone H3) was significantly reduced in corneal epithelium in Fgfr2(CKO) mice. At later stage, cell differentiation markers for corneal epithelium and underlying stromal mesenchyme, keratin-12 and keratocan respectively, were not expressed in Fgfr2(CKO) cornea. Furthermore, Pax6, a transcription factor essential for eye development, was not present in the Fgfr2(CKO) mutant corneal epithelial at E16.5 but was expressed normally at E12.5, suggesting that FGFR2-signaling is required for maintaining Pax6 expression in this tissue. Interestingly, the role of FGFR2 in corneal epithelial development is independent of ERK1/2-signaling. In contrast to the lens, FGFR2 is not required for cell survival in cornea. This study demonstrates for the first time that FGFR2 plays an essential role in controlling cell proliferation and differentiation, and maintaining Pax6 levels in corneal epithelium via ERK-independent pathways during embryonic development.

A comparative study of proliferation and osteogenic differentiation of adipose-derived stem cells on akermanite and beta-TCP ceramics.

PubMed

Liu, Qihai; Cen, Lian; Yin, Shuo; Chen, Lei; Liu, Guangpeng; Chang, Jiang; Cui, Lei

2008-12-01

This study investigated the in vitro effects of akermanite, a new kind of Ca-, Mg-, Si-containing bioceramic, on the attachment, proliferation and osteogenic differentiation of human adipose-derived stem cells (hASCs). Parallel comparison of the cellular behaviors of hASCs on the akermanite was made with those on beta-tricalcium phosphate (beta-TCP). Scanning electron microscope (SEM) observation and fluorescent DiO labeling were carried out to reveal the attachment and growth of hASCs on the two ceramic surfaces, while the quantitative assay of cell proliferation with time was detected by DNA assay. Osteogenic differentiation of hASCs cultured on the akermanite and beta-TCP was assayed by ALP expression and osteocalcin (OCN) deposition, which was further confirmed by Real-time PCR analysis for markers of osteogenic differentiation. It was shown that hASCs attached and spread well on the akermanite as those on beta-TCP, and similar proliferation behaviors of hASCs were observed on the two ceramics. Both of them exhibited good compatibility to hASCs with only minor cytotoxicity as compared with the tissue culture plates. Interestingly, the osteogenic differentiation of hASCs could be enhanced on the akermanite compared with that on the beta-TCP when the culture time was extended to approximately 10 days. Thus, it can be ascertained that akermanite ceramics may serve as a potential scaffold for bone tissue engineering.

Wnt3a regulates proliferation and migration of HUVEC via canonical and non-canonical Wnt signaling pathways

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

Samarzija, Ivana; Sini, Patrizia; Schlange, Thomas

2009-08-28

Untangling the signaling pathways involved in endothelial cell biology is of central interest for the development of antiangiogenesis based therapies. Here we report that Wnt3a induces the proliferation and migration of HUVECs, but does not affect their survival. Wnt3a-induced proliferation was VEGFR signaling independent, but reduced upon CamKII inhibition. In a search for the downstream mediators of Wnt3a's effects on HUVEC biology, we found that Wnt3a treatment leads to phosphorylation of DVL3 and stabilization of {beta}-catenin. Moreover, under the same conditions we observed an upregulation in c-MYC, TIE-2 and GJA1 mRNA transcripts. Although treatment of HUVECs with Wnt5a induced DVL3more » phosphorylation, we did not observe any of the other effects seen upon Wnt3a stimulation. Taken together, our data indicate that Wnt3a induces canonical and non-canonical Wnt signaling in HUVECs, and stimulates their proliferation and migration.« less

Cancer metabolism, stemness and tumor recurrence: MCT1 and MCT4 are functional biomarkers of metabolic symbiosis in head and neck cancer.

PubMed

Curry, Joseph M; Tuluc, Madalina; Whitaker-Menezes, Diana; Ames, Julie A; Anantharaman, Archana; Butera, Aileen; Leiby, Benjamin; Cognetti, David M; Sotgia, Federica; Lisanti, Michael P; Martinez-Outschoorn, Ubaldo E

2013-05-01

Here, we interrogated head and neck cancer (HNSCC) specimens (n = 12) to examine if different metabolic compartments (oxidative vs. glycolytic) co-exist in human tumors. A large panel of well-established biomarkers was employed to determine the metabolic state of proliferative cancer cells. Interestingly, cell proliferation in cancer cells, as marked by Ki-67 immunostaining, was strictly correlated with oxidative mitochondrial metabolism (OXPHOS) and the uptake of mitochondrial fuels, as detected via MCT1 expression (p < 0.001). More specifically, three metabolic tumor compartments were delineated: (1) proliferative and mitochondrial-rich cancer cells (Ki-67+/TOMM20+/COX+/MCT1+); (2) non-proliferative and mitochondrial-poor cancer cells (Ki-67-/TOMM20-/COX-/MCT1-); and (3) non-proliferative and mitochondrial-poor stromal cells (Ki-67-/TOMM20-/COX-/MCT1-). In addition, high oxidative stress (MCT4+) was very specific for cancer tissues. Thus, we next evaluated the prognostic value of MCT4 in a second independent patient cohort (n = 40). Most importantly, oxidative stress (MCT4+) in non-proliferating epithelial cancer cells predicted poor clinical outcome (tumor recurrence; p < 0.0001; log-rank test), and was functionally associated with FDG-PET avidity (p < 0.04). Similarly, oxidative stress (MCT4+) in tumor stromal cells was specifically associated with higher tumor stage (p < 0.03), and was a highly specific marker for cancer-associated fibroblasts (p < 0.001). We propose that oxidative stress is a key hallmark of tumor tissues that drives high-energy metabolism in adjacent proliferating mitochondrial-rich cancer cells, via the paracrine transfer of mitochondrial fuels (such as L-lactate and ketone bodies). New antioxidants and MCT4 inhibitors should be developed to metabolically target "three-compartment tumor metabolism" in head and neck cancers. It is remarkable that two "non-proliferating" populations of cells (Ki-67-/MCT4+) within the tumor can actually determine clinical outcome, likely by providing high-energy mitochondrial "fuels" for proliferative cancer cells to burn. Finally, we also show that in normal mucosal tissue, the basal epithelial "stem cell" layer is hyper-proliferative (Ki-67+), mitochondrial-rich (TOMM20+/COX+) and is metabolically programmed to use mitochondrial fuels (MCT1+), such as ketone bodies and L-lactate. Thus, oxidative mitochondrial metabolism (OXPHOS) is a common feature of both (1) normal stem cells and (2) proliferating cancer cells. As such, we should consider metabolically treating cancer patients with mitochondrial inhibitors (such as Metformin), and/or with a combination of MCT1 and MCT4 inhibitors, to target "metabolic symbiosis."

Aging of bone marrow mesenchymal stromal/stem cells: Implications on autologous regenerative medicine.

PubMed

Charif, N; Li, Y Y; Targa, L; Zhang, L; Ye, J S; Li, Y P; Stoltz, J F; Han, H Z; de Isla, N

2017-01-01

With their proliferation, differentiation into specific cell types, and secretion properties, mesenchymal stromal/stem cells (MSC) are very interesting tools to be used in regenerative medicine. Bone marrow (BM) was the first MSC source characterized. In the frame of autologous MSC therapy, it is important to detect donor's parameters affecting MSC potency. Age of the donors appears as one parameter that could greatly affect MSC properties. Moreover, in vitro cell expansion is needed to obtain the number of cells necessary for clinical developments. It will lead to in vitro cell aging that could modify cell properties. This review recapitulates several studies evaluating the effect of in vitro and in vivo MSC aging on cell properties.

Targeting Heat Shock Proteins in Cancer: A Promising Therapeutic Approach

PubMed Central

Burns, Timothy F.

2017-01-01

Heat shock proteins (HSPs) are a large family of chaperones that are involved in protein folding and maturation of a variety of “client” proteins protecting them from degradation, oxidative stress, hypoxia, and thermal stress. Hence, they are significant regulators of cellular proliferation, differentiation and strongly implicated in the molecular orchestration of cancer development and progression as many of their clients are well established oncoproteins in multiple tumor types. Interestingly, tumor cells are more HSP chaperonage-dependent than normal cells for proliferation and survival because the oncoproteins in cancer cells are often misfolded and require augmented chaperonage activity for correction. This led to the development of several inhibitors of HSP90 and other HSPs that have shown promise both preclinically and clinically in the treatment of cancer. In this article, we comprehensively review the roles of some of the important HSPs in cancer, and how targeting them could be efficacious, especially when traditional cancer therapies fail. PMID:28914774

A natural inhibitor of kidney-type glutaminase: a withanolide from Physalis pubescens with potent anti-tumor activity

PubMed Central

Wu, Canrong; Zheng, Mengzhu; Gao, Suyu; Luan, Shanshan; Cheng, Li; Wang, Liqing; Li, Jiachen; Chen, Lixia; Li, Hua

2017-01-01

Kidney-type glutaminase (KGA), a mitochondrial enzyme converting glutamine to glutamate for energy supply, was over-expressed in many cancers and had been regarded as a promising therapeutic target in recent years. Structure-based virtual ligand screening predicted physapubescin K, a new withanolide from Physalis pubescens, to be potential KGA inhibitor. Enzyme activity inhibition assays and microscale thermophoresis experiments had demonstrated the efficiency and specificity of physapubescin K targeting KGA. Additionally, physapubescin K exhibited potent proliferation inhibitory effects on a panel of human cancer cell lines, such as SW1990 and HCC827-ER. It blocked glutamine metabolism in SW1990 with increasing intracellular level of glutamine and decreasing glutamate and its downstream metabolites. Physapubescin K also significantly inhibited the tumor growth in a SW1990 xenograft mouse model. Interestingly, physapubescin K could reverse the resistance of HCC827-ER cells to erlotinib and synergize with the hexokinase 2 inhibitor to markedly enhance the inhibition of SW1990 cell proliferation. PMID:29371926

Regulation of the p27Kip1 tumor suppressor by miR-221 and miR-222 promotes cancer cell proliferation

PubMed Central

le Sage, Carlos; Nagel, Remco; Egan, David A; Schrier, Mariette; Mesman, Elly; Mangiola, Annunziato; Anile, Corrado; Maira, Giulio; Mercatelli, Neri; Ciafrè, Silvia Anna; Farace, Maria Giulia; Agami, Reuven

2007-01-01

MicroRNAs (miRNAs) are potent post-transcriptional regulators of protein coding genes. Patterns of misexpression of miRNAs in cancer suggest key functions of miRNAs in tumorigenesis. However, current bioinformatics tools do not entirely support the identification and characterization of the mode of action of such miRNAs. Here, we used a novel functional genetic approach and identified miR-221 and miR-222 (miR-221&222) as potent regulators of p27Kip1, a cell cycle inhibitor and tumor suppressor. Using miRNA inhibitors, we demonstrate that certain cancer cell lines require high activity of miR-221&222 to maintain low p27Kip1 levels and continuous proliferation. Interestingly, high levels of miR-221&222 appear in glioblastomas and correlate with low levels of p27Kip1 protein. Thus, deregulated expression of miR-221&222 promotes cancerous growth by inhibiting the expression of p27Kip1. PMID:17627278

Long Noncoding RNA HOTAIR Modulates MiR-206-mediated Bcl-w Signaling to Facilitate Cell Proliferation in Breast Cancer.

PubMed

Ding, Wei; Ren, Jin; Ren, Hui; Wang, Dan

2017-12-08

LncRNA HOX transcript antisense RNA (HOTAIR) is involved in lots of cancers. The pro-survival protein Bcl-w is frequently found in cancer development. However, the effect of HOTAIR on Bcl-w in breast cancer is not well documented. In this study, we first evaluated the correlation between HOTAIR level and Bcl-w expression in clinical breast cancer tissues. We observed that the expression levels of Bcl-w were much higher in the breast cancer samples than that in their paired noncancerous tissues. Moreover, the levels of HOTAIR were positively associated with those of Bcl-w in clinical breast cancer samples. As expected, we observed that HOTAIR was able to up-regulate the expression of Bcl-w in breast cancer cells. Mechanistically, we found that miR-206 was capable of inhibiting the expression of Bcl-w by directly binding to the 3'UTR of Bcl-w mRNA. Interestingly, HOTAIR could increase the expression of Bcl-w through sequestering miR-206 at post-transcriptional level. Functionally, our data showed that HOTAIR-induced Bcl-w by miR-206 facilitated the proliferation of breast cancer cells. Thus, we conclude that HOTAIR up-regulates Bcl-w to enhance cell proliferation through sequestering miR-206 in breast cancer. Our finding provides new insights into the mechanism of breast cancer mediated by HOTAIR.

Decreased LRIG1 in Human Ovarian Cancer Cell SKOV3 Upregulates MRP-1 and Contributes to the Chemoresistance of VP16.

PubMed

Yang, Hua; Yao, Jun; Yin, Jiangpin; Wei, Xuan

2016-05-01

The leucine-rich repeats and immunoglobulin-like domains (LRIG) are used as tumor suppressors in clinical applications. Although the LRIG has been identified to manipulate the cell proliferation via various oncogenic receptor tyrosine kinases in diverse cancers, its role in multidrug resistance needs to be further elucidated, especially in human ovarian cancer. We herein established that the etoposide (VP16)-resistant SKOV3 human ovarian cancer cell clones (SKOV3/VP16 cells) and mRNA expression of LRIG1 were significantly reduced by the treatment of VP16 in a concentration-dependent manner. Moreover, downregulated LRIG1 in SKOV3 could enhance the colony formation and resist the inhibition of proliferation by VP16, leading to the elevated expression of Bcl-2 and decreased apoptosis of SKOV3. Interestingly, our results uncovered that the multidrug resistance-associated protein 1 (MRP-1) was upregulated for the chemoresistance of VP16. To overcome the chemoresistance of SKOV3, SKOV3/VP16 was ectopically expressed of LRIG1. We found that the inhibition of VP16 on colony formation and proliferation was remarkably enhanced with increased apoptosis in SKOV3/VP16. Furthermore, the expression of MRP-1 and Bcl-2 was also inhibited, suggesting that the LRIG1could negatively control MRP-1 and the apoptosis to improve the sensitivity of VP16-related chemotherapy.

Akt SUMOylation regulates cell proliferation and tumorigenesis.

PubMed

Li, Rong; Wei, Jie; Jiang, Cong; Liu, Dongmei; Deng, Lu; Zhang, Kai; Wang, Ping

2013-09-15

Proto-oncogene Akt plays essential roles in cell proliferation and tumorigenesis. Full activation of Akt is regulated by phosphorylation, ubiquitination, and acetylation. Here we report that SUMOylation of Akt is a novel mechanism for its activation. Systematically analyzing the role of lysine residues in Akt activation revealed that K276, which is located in a SUMOylation consensus motif, is essential for Akt activation. Ectopic or endogenous Akt1 could be modified by SUMOylation. RNA interference-mediated silencing of UBC9 reduced Akt SUMOylation, which was promoted by SUMO E3 ligase PIAS1 and reversed by the SUMO-specific protease SENP1. Although multiple sites on Akt could be SUMOylated, K276 was identified as a major SUMO acceptor site. K276R or E278A mutation reduced SUMOylation of Akt but had little effect on its ubiquitination. Strikingly, these mutations also completely abolished Akt kinase activity. In support of these results, we found that expression of PIAS1 and SUMO1 increased Akt activity, whereas expression of SENP1 reduced Akt1 activity. Interestingly, the cancer-derived mutant E17K in Akt1 that occurs in various cancers was more efficiently SUMOylated than wild-type Akt. Moreover, SUMOylation loss dramatically reduced Akt1 E17K-mediated cell proliferation, cell migration, and tumorigenesis. Collectively, our findings establish that Akt SUMOylation provides a novel regulatory mechanism for activating Akt function. ©2013 AACR.

Increased Cell Proliferation and Gene Expression of Genes Related to Bone Remodeling, Cell Adhesion and Collagen Metabolism in the Periodontal Ligament of Unopposed Molars in Growing Rats

PubMed Central

Dorotheou, Domna; Farsadaki, Vassiliki; Bochaton-Piallat, Marie-Luce; Giannopoulou, Catherine; Halazonetis, Thanos D.; Kiliaridis, Stavros

2017-01-01

Tooth eruption, the process by which teeth emerge from within the alveolar bone into the oral cavity, is poorly understood. The post-emergent phase of tooth eruption continues throughout life, in particular, if teeth are not opposed by antagonists. The aim of the present study was to better understand the molecular processes underlying post-emergent tooth eruption. Toward this goal, we removed the crowns of the maxillary molars on one side of the mouth of 14 young rats and examined gene expression patterns in the periodontal ligaments (PDLs) of the ipsilateral and contralateral mandibular molars, 3 and 15 days later. Nine untreated rats served as controls. Expression of six genes, Adamts18, Ostn, P4ha3, Panx3, Pth1r, and Tnmd, was upregulated in unopposed molars relative to molars with antagonists. These genes function in osteoblast differentiation and proliferation, cell adhesion and collagen metabolism. Proliferation of PDL cells also increased following loss of the antagonist teeth. Interestingly, mutations in PTH1R have been linked to defects in the post-emergent phase of tooth eruption in humans. We conclude that post-emergent eruption of unopposed teeth is associated with gene expression patterns conducive to alveolar bone formation and PDL remodeling. PMID:28239357

Formulation Changes Affect Material Properties and Cell Behavior in HA-Based Hydrogels.

PubMed

Lawyer, Thomas; McIntosh, Kristen; Clavijo, Cristian; Potekhina, Lydia; Mann, Brenda K

2012-01-01

To develop and optimize new scaffold materials for tissue engineering applications, it is important to understand how changes to the scaffold affect the cells that will interact with that scaffold. In this study, we used a hyaluronic acid- (HA-) based hydrogel as a synthetic extracellular matrix, containing modified HA (CMHA-S), modified gelatin (Gtn-S), and a crosslinker (PEGda). By varying the concentrations of these components, we were able to change the gelation time, enzymatic degradation, and compressive modulus of the hydrogel. These changes also affected fibroblast spreading within the hydrogels and differentially affected the proliferation and metabolic activity of fibroblasts and mesenchymal stem cells (MSCs). In particular, PEGda concentration had the greatest influence on gelation time, compressive modulus, and cell spreading. MSCs appeared to require a longer period of adjustment to the new microenvironment of the hydrogels than fibroblasts. Fibroblasts were able to proliferate in all formulations over the course of two weeks, but MSCs did not. Metabolic activity changed for each cell type during the two weeks depending on the formulation. These results highlight the importance of determining the effect of matrix composition changes on a particular cell type of interest in order to optimize the formulation for a given application.

Andrographolide, a potential cancer therapeutic agent isolated from Andrographis paniculata.

PubMed

Rajagopal, Sriram; Kumar, R Ajaya; Deevi, Dhanvanthri S; Satyanarayana, Chitkala; Rajagopalan, R

2003-01-01

Andrographis paniculata plant extract is known to possess a variety of pharmacological activities. Andrographolide, the major constituent of the extract is implicated towards its pharmacological activity. We studied the cellular processes and targets modulated by andrographolide treatment in human cancer and immune cells. Andrographolide treatment inhibited the in vitro proliferation of different tumor cell lines, representing various types of cancers. The compound exerts direct anticancer activity on cancer cells by cell-cycle arrest at G0/G1 phase through induction of cell-cycle inhibitory protein p27 and decreased expression of cyclin-dependent kinase 4 (CDK4). Immunostimulatory activity of andrographolide is evidenced by increased proliferation of lymphocytes and production of interleukin-2. Andrographolide also enhanced the tumor necrosis factor-alpha production and CD marker expression, resulting in increased cytotoxic activity of lymphocytes against cancer cells, which may contribute for its indirect anticancer activity. The in vivo anticancer activity of the compound is further substantiated against B16F0 melanoma syngenic and HT-29 xenograft models. These results suggest that andrographolide is an interesting pharmacophore with anticancer and immunomodulatory activities and hence has the potential for being developed as a cancer therapeutic agent.

Midgut epithelium in molting silkworm: A fine balance among cell growth, differentiation, and survival.

PubMed

Franzetti, Eleonora; Casartelli, Morena; D'Antona, Paola; Montali, Aurora; Romanelli, Davide; Cappellozza, Silvia; Caccia, Silvia; Grimaldi, Annalisa; de Eguileor, Magda; Tettamanti, Gianluca

2016-07-01

The midgut of insects has attracted great attention as a system for studying intestinal stem cells (ISCs) as well as cell death-related processes, such as apoptosis and autophagy. Among insects, Lepidoptera represent a good model to analyze these cells and processes. In particular, larva-larva molting is an interesting developmental phase since the larva must deal with nutrient starvation and its organs are subjected to rearrangements due to proliferation and differentiation events. Several studies have analyzed ISCs in vitro and characterized key factors involved in their division and differentiation during molt. However, in vivo studies performed during larva-larva transition on these cells, and on the whole midgut epithelium, are fragmentary. In the present study, we analyzed the larval midgut epithelium of the silkworm, Bombyx mori, during larva-larva molting, focusing our attention on ISCs. Moreover, we investigated the metabolic changes that occur in the epithelium and evaluated the intervention of autophagy. Our data on ISCs proliferation and differentiation, autophagy activation, and metabolic and functional activities of the midgut cells shed light on the complexity of this organ during the molting phase. Copyright © 2016 Elsevier Ltd. All rights reserved.

Cytoprotective effects of atmospheric-pressure plasmas against hypoxia-induced neuronal injuries

NASA Astrophysics Data System (ADS)

Yan, Xu; Meng, Zhaozhong; Ouyang, Jiting; Qiao, Yajun; Li, Jiaxin; Jia, Mei; Yuan, Fang; (Ken Ostrikov, Kostya

2018-02-01

Atmospheric pressure plasma jet (APPJ) has recently been the focus of cytoprotective research due to the physiological roles of ROS and RNS. In the current study, we investigated the effect of APPJ treatment on the hypoxia (1% oxygen) induced cell injuries. SH-SY5Y cells were treated by APPJ for different duration and incubated in normoxic condition (20% oxygen) for 5 h followed by 24 h hypoxia treatment. Cell viability was evaluated by lactate dehydrogenase (LDH) release and further monitored using the electric cell-substrate impedance sensing (ECIS) system after APPJ treatment. Results showed that APPJ could reduce cell injuries after 24 h hypoxia, which was consistent with the ECIS results. Furthermore, extracellular NO and H2O2 production was significantly increased with the APPJ treatment. It was also interesting to find that APPJ treatment reduced SH-SY5Y cells proliferation in the hypoxic microenvironment during the first 20 h of hypoxia. Although more work was still need to clarify whether the cell viability maintenance was related to the cell proliferation during hypoxia, our results provide the first evidence of real-time cell viability changes after APPJ treatment under both normoxic and hypoxic conditions, which could provide evidence for the neuroprotective applications of APPJ.

Silencing by nuclear matrix attachment distinguishes cell-type specificity: association with increased proliferation capacity.

PubMed

Linnemann, Amelia K; Krawetz, Stephen A

2009-05-01

DNA loop organization by nuclear scaffold/matrix attachment is a key regulator of gene expression that may provide a means to modulate phenotype. We have previously shown that attachment of genes to the NaCl-isolated nuclear matrix correlates with their silencing in HeLa cells. In contrast, expressed genes were associated with the lithium 3,5-diiodosalicylate (LIS)-isolated nuclear scaffold. To define their role in determining phenotype matrix attached regions (MARs) on human chromosomes 14-18 were identified as a function of expression in a primary cell line. The locations of MARs in aortic adventitial fibroblast (AoAF) cells were very stable (r = 0.909) and 96% of genes attached at MARs are silent (P < 0.001). Approximately one-third of the genes uniquely expressed in AoAF cells were associated with the HeLa cell nuclear matrix and silenced. Comparatively, 81% were associated with the AoAF cell nuclear scaffold (P < 0.001) and expressed. This suggests that nuclear scaffold/matrix association mediates a portion of cell type-specific gene expression thereby modulating phenotype. Interestingly, nuclear matrix attachment and thus silencing of specific genes that regulate proliferation and maintain the integrity of the HeLa cell genome suggests that transformation may at least in part be achieved through aberrant nuclear matrix attachment.

FGF2 and insulin signaling converge to regulate cyclin D expression in multipotent neural stem cells.

PubMed

Adepoju, Adedamola; Micali, Nicola; Ogawa, Kazuya; Hoeppner, Daniel J; McKay, Ronald D G

2014-03-01

The ex vivo expansion of stem cells is making major contribution to biomedical research. The multipotent nature of neural precursors acutely isolated from the developing central nervous system has been established in a series of studies. Understanding the mechanisms regulating cell expansion in tissue culture would support their expanded use either in cell therapies or to define disease mechanisms. Basic fibroblast growth factor (FGF2) and insulin, ligands for tyrosine kinase receptors, are sufficient to sustain neural stem cells (NSCs) in culture. Interestingly, real-time imaging shows that these cells become multipotent every time they are passaged. Here, we analyze the role of FGF2 and insulin in the brief period when multipotent cells are present. FGF2 signaling results in the phosphorylation of Erk1/2, and activation of c-Fos and c-Jun that lead to elevated cyclin D mRNA levels. Insulin signals through the PI3k/Akt pathway to regulate cyclins at the post-transcriptional level. This precise Boolean regulation extends our understanding of the proliferation of multipotent NSCs and provides a basis for further analysis of proliferation control in the cell states defined by real-time mapping of the cell lineages that form the central nervous system. © 2013 AlphaMed Press.

Effects of glucocorticoid hormones on cell proliferation in dimethylhydrazine-induced tumours in rat colon.

PubMed

Tutton, P J; Barkla, D H

1981-01-01

Adrenocortical hormones have previously been shown to influence cell proliferation in many tissues. In this report, their influence on cell proliferation in the colonic crypt epithelium and in colonic adenocarcinomata is compared. Colonic tumour cell proliferation was found to be retarded following adrenalectomy and this retardation was reversible by administration of hydrocortisone, or by administration of synthetic steroids with predominantly glucocorticoid activity. Tumour cell proliferation in adrenalectomized rats was not promoted by the mineralocorticoid hormone aldosterone. Neither adrenalectomy, nor adrenocortical hormone treatment, significantly influenced colonic crypt cell proliferation.

Novel Pactamycin Analogs Induce p53 Dependent Cell-Cycle Arrest at S-Phase in Human Head and Neck Squamous Cell Carcinoma (HNSCC) Cells

PubMed Central

Guha, Gunjan; Liang, Xiaobo; Kulesz-Martin, Molly F.; Mahmud, Taifo; Indra, Arup Kumar; Ganguli-Indra, Gitali

2015-01-01

Pactamycin, although putatively touted as a potent antitumor agent, has never been used as an anticancer drug due to its high cytotoxicity. In this study, we characterized the effects of two novel biosynthetically engineered analogs of pactamycin, de-6MSA-7-demethyl-7-deoxypactamycin (TM-025) and 7-demethyl-7-deoxypactamycin (TM-026), in head and neck squamous cell carcinoma (HNSCC) cell lines SCC25 and SCC104. Both TM-025 and TM-026 exert growth inhibitory effects on HNSCC cells by inhibiting cell proliferation. Interestingly, unlike their parent compound pactamycin, the analogs do not inhibit synthesis of nascent protein in a cell-based assay. Furthermore, they do not induce apoptosis or autophagy in a dose- or a time-dependent manner, but induce mild senescence in the tested cell lines. Cell cycle analysis demonstrated that both analogs significantly induce cell cycle arrest of the HNSCC cells at S-phase resulting in reduced accumulation of G2/M-phase cells. The pactamycin analogs induce expression of cell cycle regulatory proteins including master regulator p53, its downstream target p21Cip1/WAF1, p27kip21, p19, cyclin E, total and phospho Cdc2 (Tyr15) and Cdc25C. Besides, the analogs mildly reduce cyclin D1 expression without affecting expression of cyclin B, Cdk2 and Cdk4. Specific inhibition of p53 by pifithrin-α reduces the percentage of cells accumulated in S-phase, suggesting contribution of p53 to S-phase increase. Altogether, our results demonstrate that Pactamycin analogs TM-025 and TM-026 induce senescence and inhibit proliferation of HNSCC cells via accumulation in S-phase through possible contribution of p53. The two PCT analogs can be widely used as research tools for cell cycle inhibition studies in proliferating cancer cells with specific mechanisms of action. PMID:25938491

Orbital fluid shear stress promotes osteoblast metabolism, proliferation and alkaline phosphates activity in vitro

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

Aisha, M.D.; Nor-Ashikin, M.N.K.; DDH, Universiti Teknologi MARA, ShahAlam 40450, Selangor

Prolonged disuse of the musculoskeletal system is associated with reduced mechanical loading and lack of anabolic stimulus. As a form of mechanical signal, the multidirectional orbital fluid shear stress transmits anabolic signal to bone forming cells in promoting cell differentiation, metabolism and proliferation. Signals are channeled through the cytoskeleton framework, directly modifying gene and protein expression. For that reason, we aimed to study the organization of Normal Human Osteoblast (NHOst) cytoskeleton with regards to orbital fluid shear (OFS) stress. Of special interest were the consequences of cytoskeletal reorganization on NHOst metabolism, proliferation, and osteogenic functional markers. Cells stimulated at 250more » RPM in a shaking incubator resulted in the rearrangement of actin and tubulin fibers after 72 h. Orbital shear stress increased NHOst mitochondrial metabolism and proliferation, simultaneously preventing apoptosis. The ratio of RANKL/OPG was reduced, suggesting that orbital shear stress has the potential to inhibit osteoclastogenesis and osteoclast activity. Increase in ALP activity and OCN protein production suggests that stimulation retained osteoblast function. Shear stress possibly generated through actin seemed to hold an anabolic response as osteoblast metabolism and functional markers were enhanced. We hypothesize that by applying orbital shear stress with suitable magnitude and duration as a non-drug anabolic treatment can help improve bone regeneration in prolonged disuse cases. - Highlights: • OFS stress transmits anabolic signals to osteoblasts. • Actin and tubulin fibers are rearranged under OFS stress. • OFS stress increases mitochondrial metabolism and proliferation. • Reduced RANKL/OPG ratio in response to OFS inhibits osteoclastogenesis. • OFS stress prevents apoptosis and stimulates ALP and OCN.« less

OPC-12759 increases proliferation of cultured rat conjunctival goblet cells.

PubMed

Ríos, José D; Shatos, Marie; Urashima, Hiroki; Tran, Hao; Dartt, Darlene A

2006-06-01

To determine if the gastroprotective drug OPC-12759 increased proliferation of rat conjunctival goblet cells in culture. Cultured goblet cells were incubated with 10(-12) to 10(-8) M OPC-12759 for 1 to 7 days. Fetal bovine serum (FBS) was used as a positive control. Cell proliferation was determined by a MTT [3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide] colorimetric assay and by immunohistochemical staining with anti-Ki-67, a marker of cell division. Goblet cells were identified by double-labeling with anti-Ki-67, a marker of cell division, and Ulex europaeus agglutinin I lectin, anti-MUC5AC and anticytokeratin 7. Stratified squamous cells were identified by using Griffonia (Bandeiraea) simplicifolia lectin and anticytokeratin 4 antibody. As determined by MTT conversion to formazan, OPC-12579 at 10(-11) M induced an almost 2-fold increase in goblet cell proliferation on Days 1 and 3 of incubation but not on Days 5 and 7. The FBS at 10% increased cell proliferation by 2- to 3-fold at each time point. Daily replenishment of OPC-12579 for 3 consecutive days induced cell proliferation at all concentrations. Proliferation as determined by the number of Ki-67 positive cells increased by 4- and 3-fold at Days 1 and 3, respectively with addition of 10(-11) M OPC-12579. The FBS at 10% induced a 10-fold increase in goblet cell proliferation on Days 1, 3, and 5. Colocalization of Ulex europaeus agglutinin I, MUC5AC and anticytokeratin 7 with Ki-67 indicated that proliferating cells were goblet cells. Proliferating cells were negative for the nongoblet cell markers Bandeiraea lectin and anticytokeratin 4. The OPC-12759 stimulates proliferation of conjunctival goblet cells in primary culture.

Circulating CD21low B cells in common variable immunodeficiency resemble tissue homing, innate-like B cells

PubMed Central

Rakhmanov, Mirzokhid; Keller, Baerbel; Gutenberger, Sylvia; Foerster, Christian; Hoenig, Manfred; Driessen, Gertjan; van der Burg, Mirjam; van Dongen, Jacques J.; Wiech, Elisabeth; Visentini, Marcella; Quinti, Isabella; Prasse, Antje; Voelxen, Nadine; Salzer, Ulrich; Goldacker, Sigune; Fisch, Paul; Eibel, Hermann; Schwarz, Klaus; Peter, Hans-Hartmut; Warnatz, Klaus

2009-01-01

The homeostasis of circulating B cell subsets in the peripheral blood of healthy adults is well regulated, but in disease it can be severely disturbed. Thus, a subgroup of patients with common variable immunodeficiency (CVID) presents with an extraordinary expansion of an unusual B cell population characterized by the low expression of CD21. CD21low B cells are polyclonal, unmutated IgM+IgD+ B cells but carry a highly distinct gene expression profile which differs from conventional naïve B cells. Interestingly, while clearly not representing a memory population, they do share several features with the recently defined memory-like tissue, Fc receptor-like 4 positive B cell population in the tonsils of healthy donors. CD21low B cells show signs of previous activation and proliferation in vivo, while exhibiting defective calcium signaling and poor proliferation in response to B cell receptor stimulation. CD21low B cells express decreased amounts of homeostatic but increased levels of inflammatory chemokine receptors. This might explain their preferential homing to peripheral tissues like the bronchoalveolar space of CVID or the synovium of rheumatoid arthritis patients. Therefore, as a result of the close resemblance to the gene expression profile, phenotype, function and preferential tissue homing of murine B1 B cells, we suggest that CD21low B cells represent a human innate-like B cell population. PMID:19666505

The potential for chemical mixtures from the environment to enable the cancer hallmark of sustained proliferative signalling.

PubMed

Engström, Wilhelm; Darbre, Philippa; Eriksson, Staffan; Gulliver, Linda; Hultman, Tove; Karamouzis, Michalis V; Klaunig, James E; Mehta, Rekha; Moorwood, Kim; Sanderson, Thomas; Sone, Hideko; Vadgama, Pankaj; Wagemaker, Gerard; Ward, Andrew; Singh, Neetu; Al-Mulla, Fahd; Al-Temaimi, Rabeah; Amedei, Amedeo; Colacci, Anna Maria; Vaccari, Monica; Mondello, Chiara; Scovassi, A Ivana; Raju, Jayadev; Hamid, Roslida A; Memeo, Lorenzo; Forte, Stefano; Roy, Rabindra; Woodrick, Jordan; Salem, Hosni K; Ryan, Elizabeth P; Brown, Dustin G; Bisson, William H

2015-06-01

The aim of this work is to review current knowledge relating the established cancer hallmark, sustained cell proliferation to the existence of chemicals present as low dose mixtures in the environment. Normal cell proliferation is under tight control, i.e. cells respond to a signal to proliferate, and although most cells continue to proliferate into adult life, the multiplication ceases once the stimulatory signal disappears or if the cells are exposed to growth inhibitory signals. Under such circumstances, normal cells remain quiescent until they are stimulated to resume further proliferation. In contrast, tumour cells are unable to halt proliferation, either when subjected to growth inhibitory signals or in the absence of growth stimulatory signals. Environmental chemicals with carcinogenic potential may cause sustained cell proliferation by interfering with some cell proliferation control mechanisms committing cells to an indefinite proliferative span. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Pyruvate kinase isoform expression alters nucleotide synthesis to impact cell proliferation

PubMed Central

Lunt, Sophia Y.; Muralidhar, Vinayak; Hosios, Aaron M.; Israelsen, William J.; Gui, Dan Y.; Newhouse, Lauren; Ogrodzinski, Martin; Hecht, Vivian; Xu, Kali; Acevedo, Paula N. Marín; Hollern, Daniel P.; Bellinger, Gary; Dayton, Talya L.; Christen, Stefan; Elia, Ilaria; Dinh, Anh T.; Stephanopoulos, Gregory; Manalis, Scott R.; Yaffe, Michael B.; Andrechek, Eran R.; Fendt, Sarah-Maria; Heiden, Matthew G. Vander

2014-01-01

SUMMARY Metabolic regulation influences cell proliferation. The influence of pyruvate kinase isoforms on tumor cells has been extensively studied, but whether PKM2 is required for normal cell proliferation is unknown. We examine how PKM2-deletion affects proliferation and metabolism in non-transformed, non-immortalized PKM2-expressing primary cells. We find that deletion of PKM2 in primary cells results in PKM1 expression and proliferation arrest. PKM1 expression, rather than PKM2 loss, is responsible for this effect, and proliferation arrest cannot be explained by cell differentiation, senescence, death, changes in gene expression, or prevention of cell growth. Instead, PKM1 expression impairs nucleotide production and the ability to synthesize DNA and progress through the cell cycle. Nucleotide biosynthesis is limiting, as proliferation arrest is characterized by severe thymidine depletion, and supplying exogenous thymine rescues both nucleotide levels and cell proliferation. Thus, PKM1 expression promotes a metabolic state that is unable to support DNA synthesis. PMID:25482511

Synthetic cyclin dependent kinase inhibitors. New generation of potent anti-cancer drugs.

PubMed

Hajdúch, M; Havlíèek, L; Veselý, J; Novotný, R; Mihál, V; Strnad, M

1999-01-01

The unsatisfactory results of current anti-cancer therapies require the active search for new drugs, new treatment strategies and a deeper understanding of the host-tumour relationship. From this point of view, the drugs with a capacity to substitute the functions of altered tumour suppressor genes are of prominent interest. Since one of the main functions of oncosuppressors is to mediate cell cycle arrest via modification of cyclin dependent kinases (CDKs) activity, the compounds with ability to substitute altered functions of these genes in neoplastic cells are of prominent interest. Synthetic inhibitors of cyclin dependent kinases (CDKIs) are typical representatives of such drugs. Olomoucine (OC), flavopiridol (FP), butyrolactone I (BL) and their derivatives selectively inhibit CDKs and thus constrain tumor cell proliferation under in vitro and/or in vivo conditions. We originally discovered OC and its inhibitory activity toward CDK1 family of CDKs, and recently reported the induction of apoptosis and tumor regression following OC application. Moreover, the OC family of synthetic CDKIs has the capacity of directly inhibit CDK7, the principal enzyme required for activating other CDKs, and thus these compounds are the first known CDK7 inhibitors. Its unique mechanism of action and potent anti-cancer activity under both in vitro and in vivo conditions provide a unique tool to inhibit tumour cell proliferation, and to selectively induce apoptosis in neoplastic tissues. The mechanisms of anti-cancer activities of FP, BL, OC and related synthetic CDKIs are compared and discussed in this paper.

Skeletal muscle hypertrophy and regeneration: interplay between the myogenic regulatory factors (MRFs) and insulin-like growth factors (IGFs) pathways.

PubMed

Zanou, Nadège; Gailly, Philippe

2013-11-01

Adult skeletal muscle can regenerate in response to muscle damage. This ability is conferred by the presence of myogenic stem cells called satellite cells. In response to stimuli such as injury or exercise, these cells become activated and express myogenic regulatory factors (MRFs), i.e., transcription factors of the myogenic lineage including Myf5, MyoD, myogenin, and Mrf4 to proliferate and differentiate into myofibers. The MRF family of proteins controls the transcription of important muscle-specific proteins such as myosin heavy chain and muscle creatine kinase. Different growth factors are secreted during muscle repair among which insulin-like growth factors (IGFs) are the only ones that promote both muscle cell proliferation and differentiation and that play a key role in muscle regeneration and hypertrophy. Different isoforms of IGFs are expressed during muscle repair: IGF-IEa, IGF-IEb, or IGF-IEc (also known as mechano growth factor, MGF) and IGF-II. MGF is expressed first and is observed in satellite cells and in proliferating myoblasts whereas IGF-Ia and IGF-II expression occurs at the state of muscle fiber formation. Interestingly, several studies report the induction of MRFs in response to IGFs stimulation. Inversely, IGFs expression may also be regulated by MRFs. Various mechanisms are proposed to support these interactions. In this review, we describe the general process of muscle hypertrophy and regeneration and decipher the interactions between the two groups of factors involved in the process.

Endosome-to-Plasma Membrane Recycling of VEGFR2 Receptor Tyrosine Kinase Regulates Endothelial Function and Blood Vessel Formation

PubMed Central

Jopling, Helen M.; Odell, Adam F.; Pellet-Many, Caroline; Latham, Antony M.; Frankel, Paul; Sivaprasadarao, Asipu; Walker, John H.; Zachary, Ian C.; Ponnambalam, Sreenivasan

2014-01-01

Rab GTPases are implicated in endosome-to-plasma membrane recycling, but how such membrane traffic regulators control vascular endothelial growth factor receptor 2 (VEGFR2/KDR) dynamics and function are not well understood. Here, we evaluated two different recycling Rab GTPases, Rab4a and Rab11a, in regulating endothelial VEGFR2 trafficking and signalling with implications for endothelial cell migration, proliferation and angiogenesis. In primary endothelial cells, VEGFR2 displays co-localisation with Rab4a, but not Rab11a GTPase, on early endosomes. Expression of a guanosine diphosphate (GDP)-bound Rab4a S22N mutant caused increased VEGFR2 accumulation in endosomes. TfR and VEGFR2 exhibited differences in endosome-to-plasma membrane recycling in the presence of chloroquine. Depletion of Rab4a, but not Rab11a, levels stimulated VEGF-A-dependent intracellular signalling. However, depletion of either Rab4a or Rab11a levels inhibited VEGF-A-stimulated endothelial cell migration. Interestingly, depletion of Rab4a levels stimulated VEGF-A-regulated endothelial cell proliferation. Rab4a and Rab11a were also both required for endothelial tubulogenesis. Evaluation of a transgenic zebrafish model showed that both Rab4 and Rab11a are functionally required for blood vessel formation and animal viability. Rab-dependent endosome-to-plasma membrane recycling of VEGFR2 is important for intracellular signalling, cell migration and proliferation during angiogenesis. PMID:24785348

Cell proliferation is a key determinant of the outcome of FOXO3a activation

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

Poulsen, Raewyn C., E-mail: raewyn.poulsen@gmail.com; Carr, Andrew J.; Hulley, Philippa A.

2015-06-19

The FOXO family of forkhead transcription factors have a pivotal role in determining cell fate in response to oxidative stress. FOXO activity can either promote cell survival or induce cell death. Increased FOXO-mediated cell death has been implicated in the pathogenesis of degenerative diseases affecting musculoskeletal tissues. The aim of this study was to determine the conditions under which one member of the FOXO family, FOXO3a, promotes cell survival as opposed to cell death. Treatment of primary human tenocytes with 1 pM hydrogen peroxide for 18 h resulted in increased protein levels of FOXO3a. In peroxide-treated cells cultured in low serum media,more » FOXO3a inhibited cell proliferation and protected against apoptosis. However in peroxide treated cells cultured in high serum media, cell proliferation was unchanged but level of apoptosis significantly increased. Similarly, in tenocytes transduced to over-express FOXO3a, cell proliferation was inhibited and level of apoptosis unchanged in cells cultured in low serum. However there was a robust increase in cell death in FOXO3a-expressing cells cultured in high serum. Inhibition of cell proliferation in either peroxide-treated or FOXO3a-expressing cells cultured in high serum protected against apoptosis induction. Conversely, addition of a Chk2 inhibitor to peroxide-treated or FOXO3a-expressing cells overrode the inhibitory effect of FOXO3a on cell proliferation and led to increased apoptosis in cells cultured in low serum. This study demonstrates that proliferating cells may be particularly susceptible to the apoptosis-inducing actions of FOXO3a. Inhibition of cell proliferation by FOXO3a may be a critical event in allowing the pro-survival rather than the pro-apoptotic activity of FOXO3a to prevail. - Highlights: • FOXO3a activity can result in either promotion of cell survival or apoptosis. • The outcome of FOXO3a activation differs in proliferating compared to non-proliferating cells. • Proliferating cells are susceptible to FOXO3a-mediated apoptosis. • Inhibition of cell proliferation by FOXO3a promotes cell survival.« less

Black cohosh inhibits 17β-estradiol-induced cell proliferation of endometrial adenocarcinoma cells.

PubMed

Park, So Yun; Kim, Hee Ja; Lee, Sa Ra; Choi, Youn-Hee; Jeong, Kyungah; Chung, Hyewon

2016-10-01

This study was conducted to investigate the effect of black cohosh (BC) extract on the proliferation and apoptosis of Ishikawa cells. Ishikawa human endometrial adenocarcinoma cells were treated with or without BC (1, 5, 10 and 25 μM) and cell proliferation and cytotoxicity were measured by CCK-8 assays and flow cytometry analysis. Additionally, Ishikawa cells were treated with 17β-estradiol (E2), E2 + progesterone and E2 + BC (5 and 10 μM) and the effect of BC and progesterone on E2-induced cell proliferation was analyzed. BC decreased the proliferation of Ishikawa cells at a dose-dependent rate compared with the control group (p < 0.05). The proliferation of Ishikawa cells increased in the presence of E2, whereas the subsequent addition of progesterone or BC decreased proliferation to the level of the control group (p < 0.05). The inhibitory effect of BC on E2-induced cell proliferation was greater than the inhibitory effect of progesterone. In conclusion, BC induces apoptosis in Ishikawa cells and suppresses E2-induced cell proliferation in Ishikawa cells. BC could be considered a candidate co-treatment agent of estrogen-dependent tumors, especially those involving endometrial cells.

Quantitative Imaging of Scattering Changes Associated With Epithelial Proliferation, Necrosis and Fibrosis in Tumors Using Microsampling Reflectance Spectroscopy

PubMed Central

Krishnaswamy, Venkataramanan; Hoopes, P. Jack; Samkoe, Kimberley S.; O'Hara, Julia A.; Hasan, Tayyaba; Pogue, Brian W.

2010-01-01

Highly localized reflectance measurements can be used to directly quantify scatter changes in tissues. This study presents a microsampling approach that is used to raster scan tumors to extract parameters believed to be related to the tissue ultra-structure. A confocal reflectance imager was developed to examine scatter changes across pathologically distinct regions within tumor tissues. Tissue sections from two murine tumors, AsPC-1 pancreas tumor and the Mat-LyLu Dunning prostate tumor, were imaged. After imaging, histopathology-guided region-of-interest studies of the images allowed analysis of the variations in scattering resulting from differences in tissue ultra-structure. On average, the median scatter power of tumor cells with high proliferation index was about 26% less compared to tumor cells with low proliferation index (LPI). Necrosis exhibited the lowest scatter power signature across all the tissue types considered, with about 55% lower median scatter power than LPI tumor cells. Additionally, the level and maturity of the tumor's fibroplastic response was found to influence the scatter signal. This approach to scatter visualization of tissue ultra-structure in situ could provide a unique tool for guiding surgical resection, but this kind of interpretation into what the signal means relative to the pathology is required before proceeding to clinical studies. PMID:19256692

Differential effects on cell motility, embryonic stem cell self-renewal and senescence by diverse Src kinase family inhibitors

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

Tamm, Christoffer, E-mail: christoffer.tamm@imbim.uu.se; Galito, Sara Pijuan, E-mail: sara.pijuan@imbim.uu.se; Anneren, Cecilia, E-mail: cecilia.anneren@imbim.uu.se

2012-02-15

The Src family of non-receptor tyrosine kinases (SFKs) has been shown to play an intricate role in embryonic stem (ES) cell maintenance. In the present study we have focused on the underlying molecular mechanisms responsible for the vastly different effects induced by various commonly used SFK inhibitors. We show that several diverse cell types, including fibroblasts completely lacking SFKs, cannot undergo mitosis in response to SU6656 and that this is caused by an unselective inhibition of Aurora kinases. In contrast, PP2 and PD173952 block motility immediately upon exposure and forces cells to grow in dense colonies. The subsequent halt inmore » proliferation of fibroblast and epithelial cells in the center of the colonies approximately 24 h post-treatment appears to be caused by cell-to-cell contact inhibition rather than a direct effect of SFK kinase inhibition. Interestingly, in addition to generating more homogenous and dense ES cell cultures, without any diverse effect on proliferation, PP2 and PD173652 also promote ES cell self-renewal by reducing the small amount of spontaneous differentiation typically observed under standard ES cell culture conditions. These effects could not be mirrored by the use of Gleevec, a potent inhibitor of c-Abl and PDGFR kinases that are also inhibited by PP2. -- Highlights: Black-Right-Pointing-Pointer SFK inhibitor SU6656 induces senescence in mouse ES cells. Black-Right-Pointing-Pointer SU6656 inhibits mitosis in a SFK-independent manner via cross-selectivity for Aurora kinases. Black-Right-Pointing-Pointer SFK inhibitor PP2 impairs cell motility in various cell lines, including mouse ES cells. Black-Right-Pointing-Pointer Ensuing impeded motility, PP2 inhibits proliferation of various cells lines except for mouse ES cells. Black-Right-Pointing-Pointer SFK inhibitors PP2 and PD173952 impede spontaneous differentiation in standard mouse ES culture maintenance.« less

Importance of inverse correlation between ALDH3A1 and PPARγ in tumor cells and tissue regeneration.

PubMed

Oraldi, M; Saracino, S; Maggiora, M; Chiaravalloti, A; Buemi, C; Martinasso, G; Paiuzzi, E; Thompson, D; Vasiliou, V; Canuto, R A

2011-05-30

Aldehyde dehydrogenase (ALDH) enzymes are involved in maintaining cellular homeostasis by metabolizing both endogenous and exogenous reactive aldehydes. They modulate several cell functions including proliferation, differentiation, survival as well as cellular response to oxidative stress. We previously reported that ALDH3A1 expression is inversely correlated with the activation of PPARs (Peroxisome Proliferators-Activated Receptors), a category of orphan nuclear hormone receptors, in both rat and human cells. PPARγ is involved in cell proliferation. In this study, we have used PPARγ transfection and inhibition to examine the relationship between ALDH3A1 and PPARγ and their role as regulators of cell proliferation. Induction of PPARγ in A549 and NCTC 2544 cells by transfection caused a decrease in ALDH3A1 and inhibition of cell proliferation, a result we obtained previously using ligands that induce PPARγ. A reduction of PPARγ expression using siRNA increased ALDH3A1 expression and cell proliferation. In cells induced to proliferate in a model of tissue regeneration, ALDH3A1 expression increased during the period of proliferation, whereas PPARγ expression decreased. In conclusion, through modulation of PPARγ or ALDH3A1, it may be possible to reduce cell proliferation in tumor cells or stimulate cell proliferation in normal cells during tissue regeneration. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Inhibition of the proliferation and acceleration of migration of vascular endothelial cells by increased cysteine-rich motor neuron 1

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

Nakashima, Yukiko; Morimoto, Mayuka; Toda, Ken-ichi

2015-07-03

Cysteine-rich motor neuron 1 (CRIM1) is upregulated only in extracellular matrix gels by angiogenic factors such as vascular endothelial growth factor (VEGF). It then plays a critical role in the tube formation of endothelial cells. In the present study, we investigated the effects of increased CRIM1 on other endothelial functions such as proliferation and migration. Knock down of CRIM1 had no effect on VEGF-induced proliferation or migration of human umbilical vein endothelial cells (HUVECs), indicating that basal CRIM1 is not involved in the proliferation or migration of endothelial cells. Stable CRIM1-overexpressing endothelial F-2 cells, termed CR1 and CR2, were constructed,more » because it was difficult to prepare monolayer HUVECs that expressed high levels of CRIM1. Proliferation was reduced and migration was accelerated in both CR1 and CR2 cells, compared with normal F-2 cells. Furthermore, the transient overexpression of CRIM1 resulted in decreased proliferation and increased migration of bovine aortic endothelial cells. In contrast, neither proliferation nor migration of COS-7 cells were changed by the overexpression of CRIM1. These results demonstrate that increased CRIM1 reduces the proliferation and accelerates the migration of endothelial cells. These CRIM1 effects might contribute to tube formation of endothelial cells. CRIM1 induced by angiogenic factors may serve as a regulator in endothelial cells to switch from proliferating cells to morphological differentiation. - Highlights: • CRIM1 was upregulated only in tubular endothelial cells, but not in monolayers. • Increased CRIM1 reduced the proliferation of endothelial cells. • Increased CRIM1 accelerated the migration of endothelial cells. • Increased CRIM1 had no effect on the proliferation or migration of COS-7 cells.« less

Human induced pluripotent stem cell-derived beating cardiac tissues on paper.

PubMed

Wang, Li; Xu, Cong; Zhu, Yujuan; Yu, Yue; Sun, Ning; Zhang, Xiaoqing; Feng, Ke; Qin, Jianhua

2015-11-21

There is a growing interest in using paper as a biomaterial scaffold for cell-based applications. In this study, we made the first attempt to fabricate a paper-based array for the culture, proliferation, and direct differentiation of human induced pluripotent stem cells (hiPSCs) into functional beating cardiac tissues and create "a beating heart on paper." This array was simply constructed by binding a cured multi-well polydimethylsiloxane (PDMS) mold with common, commercially available paper substrates. Three types of paper material (print paper, chromatography paper and nitrocellulose membrane) were tested for adhesion, proliferation and differentiation of human-derived iPSCs. We found that hiPSCs grew well on these paper substrates, presenting a three-dimensional (3D)-like morphology with a pluripotent property. The direct differentiation of human iPSCs into functional cardiac tissues on paper was also achieved using our modified differentiation approach. The cardiac tissue retained its functional activities on the coated print paper and chromatography paper with a beating frequency of 40-70 beats per min for up to three months. Interestingly, human iPSCs could be differentiated into retinal pigment epithelium on nitrocellulose membrane under the conditions of cardiac-specific induction, indicating the potential roles of material properties and mechanical cues that are involved in regulating stem cell differentiation. Taken together, these results suggest that different grades of paper could offer great opportunities as bioactive, low-cost, and 3D in vitro platforms for stem cell-based high-throughput drug testing at the tissue/organ level and for tissue engineering applications.

Cyclin D1 negatively regulates the expression of differentiation genes in HT-29 M6 mucus-secreting colon cancer cells.

PubMed

Mayo, Clara; Mayol, Xavier

2009-08-28

HT-29 M6 colon cancer cells differentiate to a mucus-secreting phenotype in culture. We found that the pattern of cyclin D1 expression in HT-29 M6 cells did not correlate with instances of cell proliferation but was specifically induced during a dedifferentiation process following disaggregation of epithelial cell layers, even under conditions that did not allow cell cycle reentrance. Interestingly, ectopic expression of cyclin D1 in differentiated cells led to the inhibition of the transcriptional activity of differentiation gene promoters, such as the mucin MUC1. We thus propose that the overexpression of cyclin D1 found in colon cancer favours tumour dedifferentiation as one mechanism of tumour progression.

Molecular Cogs: Interplay between Circadian Clock and Cell Cycle.

PubMed

Gaucher, Jonathan; Montellier, Emilie; Sassone-Corsi, Paolo

2018-05-01

The cell cycle and the circadian clock operate as biological oscillators whose timed functions are tightly regulated. Accumulating evidence illustrates the presence of molecular links between these two oscillators. This mutual interplay utilizes various coupling mechanisms, such as the use of common regulators. The connection between these two cyclic systems has unique interest in the context of aberrant cell proliferation since both of these oscillators are frequently misregulated in cancer cells. Further studies will provide deeper understanding of the detailed molecular connections between the cell cycle and the circadian clock and may also serve as a basis for the design of innovative therapeutic strategies. Copyright © 2018 Elsevier Ltd. All rights reserved.

Low concentrations of alendronate increase the local invasive potential of osteoblastic sarcoma cell lines via connexin 43 activation.

PubMed

Yoshitani, Kazuhiro; Kido, Akira; Honoki, Kanya; Akahane, Manabu; Fujii, Hiromasa; Tanaka, Yasuhito

2011-07-15

Bisphosphonates (BPs) are agents used for treating disorders of excessive bone resorption. In addition, due to their cell-killing activity, BPs were potent candidates for adjuvant cancer therapy. On the other hand, low-concentrations of BPs have been reported to increase cellular viability in several types of tumor cells. Therefore, we focused on the effect of BPs on cellular aggressiveness of malignant bone tumors at low concentrations. MTS assay was performed using osteosarcoma cell lines MG63 and HOS, fibrosarcoma cell line HT1080, and prostate cancer cell line PC3. All the cell lines showed toxicity at high concentrations. On the other hand, at lower concentrations, the cellular viabilities of HOS and MG63 were rather higher than those of untreated controls. Since this tendency was most evident, HOS was used for further assays, including cellular motility, bone resorption activity, and cathepsin K activity. The low-concentration of alendronate enhanced cellular viability and motility, which correlated with the expression of connexin 43 at the mRNA and protein levels. Interestingly, oleamide, a potent connexin 43 inhibitor, had an inhibitory effect on the enhanced proliferation. Our data suggest that alendronate may enhance the proliferation of osteoblastic cell line through connexin 43 activation. Copyright © 2011 Elsevier GmbH. All rights reserved.

Podocytes populate cellular crescents in a murine model of inflammatory glomerulonephritis.

PubMed

Moeller, Marcus J; Soofi, Abdulsalaam; Hartmann, Inge; Le Hir, Michel; Wiggins, Roger; Kriz, Wilhelm; Holzman, Lawrence B

2004-01-01

Cellular crescents are a defining histologic finding in many forms of inflammatory glomerulonephritis. Despite numerous studies, the origin of glomerular crescents remains unresolved. A genetic cell lineage-mapping study with a novel transgenic mouse model was performed to investigate whether visceral glomerular epithelial cells, termed podocytes, are precursors of cells that populate cellular crescents. The podocyte-specific 2.5P-Cre mouse line was crossed with the ROSA26 reporter line, resulting in irreversible constitutive expression of beta-galactosidase in doubly transgenic 2.5P-Cre/ROSA26 mice. In these mice, crescentic glomerulonephritis was induced with a previously described rabbit anti-glomerular basement membrane antiserum nephritis approach. Interestingly, beta-galactosidase-positive cells derived from podocytes adhered to the parietal basement membrane and populated glomerular crescents during the early phases of cellular crescent formation, accounting for at least one-fourth of the total cell mass. In cellular crescents, the proliferation marker Ki-67 was expressed in beta-galactosidase-positive and beta-galactosidase-negative cells, indicating that both cell types contributed to the formation of cellular crescents through proliferation in situ. Podocyte-specific antigens, including WT-1, synaptopodin, nephrin, and podocin, were not expressed by any cells in glomerular crescents, suggesting that podocytes underwent profound phenotypic changes in this nephritis model.

MicroRNA-155 facilitates skeletal muscle regeneration by balancing pro- and anti-inflammatory macrophages

PubMed Central

Nie, M; Liu, J; Yang, Q; Seok, H Y; Hu, X; Deng, Z-L; Wang, D-Z

2016-01-01

Skeletal muscle has remarkable regeneration capacity and regenerates in response to injury. Muscle regeneration largely relies on muscle stem cells called satellite cells. Satellite cells normally remain quiescent, but in response to injury or exercise they become activated and proliferate, migrate, differentiate, and fuse to form multinucleate myofibers. Interestingly, the inflammatory process following injury and the activation of the myogenic program are highly coordinated, with myeloid cells having a central role in modulating satellite cell activation and regeneration. Here, we show that genetic deletion of microRNA-155 (miR-155) in mice substantially delays muscle regeneration. Surprisingly, miR-155 does not appear to directly regulate the proliferation or differentiation of satellite cells. Instead, miR-155 is highly expressed in myeloid cells, is essential for appropriate activation of myeloid cells, and regulates the balance between pro-inflammatory M1 macrophages and anti-inflammatory M2 macrophages during skeletal muscle regeneration. Mechanistically, we found that miR-155 suppresses SOCS1, a negative regulator of the JAK-STAT signaling pathway, during the initial inflammatory response upon muscle injury. Our findings thus reveal a novel role of miR-155 in regulating initial immune responses during muscle regeneration and provide a novel miRNA target for improving muscle regeneration in degenerative muscle diseases. PMID:27277683

Platelet lysate from whole blood-derived pooled platelet concentrates and apheresis-derived platelet concentrates for the isolation and expansion of human bone marrow mesenchymal stromal cells: production process, content and identification of active components

PubMed Central

Fekete, Natalie; Gadelorge, Mélanie; Fürst, Daniel; Maurer, Caroline; Dausend, Julia; Fleury-Cappellesso, Sandrine; Mailänder, Volker; Lotfi, Ramin; Ignatius, Anita; Sensebé, Luc; Bourin, Philippe; Schrezenmeier, Hubert; Rojewski, Markus Thomas

2012-01-01

Background aims The clinical use of human mesenchymal stromal cells (MSC) requires ex vivo expansion in media containing supplements such as fetal bovine serum or, alternatively, human platelet lysate (PL). Methods Platelet concentrates were frozen, quarantine stored, thawed and sterile filtered to obtain PL. PL content and its effect on fibroblast-colony-forming unit (CFU-F) formation, MSC proliferation and large-scale expansion were studied. Results PL contained high levels of basic fibroblast growth factor (bFGF), soluble CD40L (sCD40L), vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), platelet-derived growth factor AA (PDGF-AA), platelet-derived growth factor AB/BB (PDGF-AB/BB), chemokine (C-C) ligand 5 (CCL5; RANTES) transforming growth factor-β1 (TGF-β1) and chemokine (C-X-C) ligand 1/2/3 (GRO), with low batch-to-batch variability, and most were stable for up to 14 days. Inhibition of PDGF-BB and bFGF decreased MSC proliferation by about 20% and 50%, respectively. The strongest inhibition (about 75%) was observed with a combination of anti-bFGF + anti-PDGF-BB and anti-bFGF + anti-TGF-β1 + anti-PDGF-BB. Interestingly, various combinations of recombinant PDGF-BB, bFGF and TGF-β1 were not sufficient to promote cell proliferation. PL from whole blood-derived pooled platelet concentrates and apheresis platelet concentrates did not differ significantly in their growth-promoting activity on MSC. Conclusions PL enhances MSC proliferation and can be regarded as a safe tool for MSC expansion for clinical purposes. \\in particular, PDGF-BB and bFGF are essential components for the growth-promoting effect of PL, but are not sufficient for MSC proliferation. PMID:22296115

Functional characterization of cell hybrids generated by induced fusion of primary porcine mesenchymal stem cells with an immortal murine cell line.

PubMed

Islam, M Q; Ringe, J; Reichmann, E; Migotti, R; Sittinger, M; da S Meirelles, L; Nardi, N B; Magnusson, P; Islam, K

2006-10-01

Bone marrow mesenchymal stem cells (MSC) integrate into various organs and contribute to the regeneration of diverse tissues. However, the mechanistic basis of the plasticity of MSC is not fully understood. The change of cell fate has been suggested to occur through cell fusion. We have generated hybrid cell lines by polyethylene-glycol-mediated cell fusion of primary porcine MSC with the immortal murine fibroblast cell line F7, a derivative of the GM05267 cell line. The hybrid cell lines display fibroblastic morphology and proliferate like immortal cells. They contain tetraploid to hexaploid porcine chromosomes accompanied by hypo-diploid murine chromosomes. Interestingly, many hybrid cell lines also express high levels of tissue-nonspecific alkaline phosphatase, which is considered to be a marker of undifferentiated embryonic stem cells. All tested hybrid cell lines retain osteogenic differentiation, a few of them also retain adipogenic potential, but none retain chondrogenic differentiation. Conditioned media from hybrid cells enhance the proliferation of both early-passage and late-passage porcine MSC, indicating that the hybrid cells secrete diffusible growth stimulatory factors. Murine F7 cells thus have the unique property of generating immortal cell hybrids containing unusually high numbers of chromosomes derived from normal cells. These hybrid cells can be employed in various studies to improve our understanding of regenerative biology. This is the first report, to our knowledge, describing the generation of experimentally induced cell hybrids by using normal primary MSC.

HOXA9 is critical in the proliferation, differentiation, and malignancy of leukaemia cells both in vitro and in vivo.

PubMed

Chen, Shibing; Yu, Juan; Lv, Xin; Zhang, Lijuan

2017-10-01

Progress in the understanding of the molecular mechanism for acute myeloid leukaemia is of great significance to generate new potential targets for treatment. Recent studies showed that HOXA9, a homeodomain-containing transcription factor, is commonly deregulated in acute leukaemia. In this study, we elucidated the direct correlation between HoxA9 expression and progression of leukaemia using 2 different types of leukaemia cells HL-60 and MOLT-3. The HoxA9 expression level was decreased in leukaemia cells with the treatment of all-trans retinoic acid or arsenic trioxide (As 2 O 3 ). Downregulation of HoxA9 could impair the proliferation and promote the leukaemia cell death. HoxA9 silencing also potentiated the differentiation of leukaemia cells, and in vivo studies demonstrated that HoxA9 downregulation could interfere the tumour growth. Interestingly, HoxA9 silencing also led to the alteration in miRNA expression, mediating the promoting effect on the leukaemia cell differentiation. Therefore, this work provided a promising and potentially efficient target to leukaemia treatment, indicating that HoxA9 is likely to be an ideal candidate in the gene therapy against acute myeloid leukaemia. In this study, we elucidated the critical role of HoxA9 in the proliferation and differentiation of leukaemia cells both in vitro and in vivo. The effect of HoxA9 modulation was correlated with the clinical effect of all-trans retinoic acid and As 2 O 3 . Furthermore, HoxA9 also regulated the miRNA expression, controlling the leukaemia cell differentiation. Therefore, this work provided new insights into molecular mechanism underlying the leukaemia treatment, potentially putting forward a brand new target to the gene therapy against leukaemia. Copyright © 2017 John Wiley & Sons, Ltd.

The receptor protein tyrosine phosphatase PTPRJ negatively modulates the CD98hc oncoprotein in lung cancer cells

PubMed Central

D’Agostino, Sabrina; Lanzillotta, Delia; Varano, Mariaconcetta; Botta, Cirino; Baldrini, Antonio; Bilotta, Anna; Scalise, Stefania; Dattilo, Vincenzo; Amato, Rosario; Gaudio, Eugenio; Paduano, Francesco; Palmieri, Camillo; Iuliano, Rodolfo; Perrotti, Nicola; Indiveri, Cesare; Fusco, Alfredo; Gaspari, Marco; Trapasso, Francesco

2018-01-01

PTPRJ, a receptor protein tyrosine phosphatase strongly downregulated in human cancer, displays tumor suppressor activity by negatively modulating several proteins involved in proliferating signals. Here, through a proteomic-based approach, we identified a list of potential PTPRJ-interacting proteins and among them we focused on CD98hc, a type II glycosylated integral membrane protein encoded by SLC3A2, corresponding to the heavy chain of a heterodimeric transmembrane amino-acid transporter, including LAT1. CD98hc is widely overexpressed in several types of cancers and contributes to the process of tumorigenesis by interfering with cell proliferation, adhesion, and migration. We first validated PTPRJ-CD98hc interaction, then demonstrated that PTPRJ overexpression dramatically reduces CD98hc protein levels in A549 lung cancer cells. In addition, following to the treatment of PTPRJ-transduced cells with MG132, a proteasome inhibitor, CD98hc levels did not decrease compared to controls, indicating that PTPRJ is involved in the regulation of CD98hc proteasomal degradation. Moreover, PTPRJ overexpression combined with CD98hc silencing consistently reduced cell proliferation and triggered apoptosis of lung cancer cells. Interestingly, by interrogating the can Evolve database, we observed an inverse correlation between PTPRJ and SLC3A2 gene expression. Indeed, the non-small cell lung cancers (NSCLCs) of patients showing a short survival rate express the lowest and the highest levels of PTPRJ and SLC3A2, respectively. Therefore, the results reported here contribute to shed lights on PTPRJ signaling in cancer cells: moreover, our findings also support the development of a novel anticancer therapeutic approach by targeting the pathway of PTPRJ that is usually downregulated in highly malignant human neoplasias.

Spatial distribution and cellular composition of adult brain proliferative zones in the teleost, Gymnotus omarorum

PubMed Central

Olivera-Pasilio, Valentina; Peterson, Daniel A.; Castelló, María E.

2014-01-01

Proliferation of stem/progenitor cells during development provides for the generation of mature cell types in the CNS. While adult brain proliferation is highly restricted in the mammals, it is widespread in teleosts. The extent of adult neural proliferation in the weakly electric fish, Gymnotus omarorum has not yet been described. To address this, we used double thymidine analog pulse-chase labeling of proliferating cells to identify brain proliferation zones, characterize their cellular composition, and analyze the fate of newborn cells in adult G. omarorum. Short thymidine analog chase periods revealed the ubiquitous distribution of adult brain proliferation, similar to other teleosts, particularly Apteronotus leptorhynchus. Proliferating cells were abundant at the ventricular-subventricular lining of the ventricular-cisternal system, adjacent to the telencephalic subpallium, the diencephalic preoptic region and hypothalamus, and the mesencephalic tectum opticum and torus semicircularis. Extraventricular proliferation zones, located distant from the ventricular-cisternal system surface, were found in all divisions of the rombencephalic cerebellum. We also report a new adult proliferation zone at the caudal-lateral border of the electrosensory lateral line lobe. All proliferation zones showed a heterogeneous cellular composition. The use of short (24 h) and long (30 day) chase periods revealed abundant fast cycling cells (potentially intermediate amplifiers), sparse slow cycling (potentially stem) cells, cells that appear to have entered a quiescent state, and cells that might correspond to migrating newborn neural cells. Their abundance and migration distance differed among proliferation zones: greater numbers and longer range and/or pace of migrating cells were associated with subpallial and cerebellar proliferation zones. PMID:25249943

c-erbA and v-erbA modulate growth and gene expression of a mouse glial precursor cell line.

PubMed

Iglesias, T; Llanos, S; López-Barahona, M; Pérez-Aranda, A; Rodríguez-Peña, A; Bernal, J; Höhne, A; Seliger, B; Muñoz, A

1994-07-01

The c-erbA alpha protooncogene coding for the thyroid hormone (T3) receptor (TR alpha 1) and the viral, mutated v-erbA oncogene were expressed in an immortal mouse glial cell line (B3.1) using retroviral vectors. c-erbA alpha expression led to a decrease in cell proliferation in high and low serum conditions, both in the presence and in the absence of T3. In serum-free medium, c-erbA-expressing cells (B3.1 + TR alpha 1) were completely arrested, whereas cells expressing v-erbA (B3.1 + v-erbA) showed a higher DNA synthesis rate than normal B3.1 cells. Although proliferation of all three cell types was stimulated by platelet-derived growth factor and basic fibroblast growth factor, differences were also observed in the response to these agents. B3.1 + TR alpha 1 cells were more sensitive to platelet-derived growth factor than B3.1 and B3.1 + v-erbA cells. In contrast, B3.1 cells responded to basic fibroblast growth factor better than B3.1 + TR alpha 1 or B3.1 + v-erbA cells. Insulin-like growth factor I potentiated the action of platelet-derived growth factor and basic fibroblast growth factor. Again, different responses to treatment with insulin-like growth factor I alone were observed; B3.1 + TR alpha 1 cells did not respond to it, whereas B3.1 + v-erbA cells showed a dramatic stimulation by this agent. Interestingly, in the presence of T3, the blockade in B3.1 + TR alpha 1 cell proliferation was accompanied by the down-regulation of the typical astrocytic genes, glial fibrillary acidic protein and vimentin. These hormone effects were not found in v-erbA-expressing cells. In addition, v-erbA inhibited the basal expression of the cyclic nucleotide phosphodiesterase gene, an oligodendrocytic marker.(ABSTRACT TRUNCATED AT 250 WORDS)

Inhibitory effect of PDGF-BB and serum-stimulated responses in vascular smooth muscle cell proliferation by hinokitiol via up-regulation of p21 and p53.

PubMed

Li, Jiun-Yi; Liu, Chun-Ping; Shiao, Wei-Cheng; Jayakumar, Thanasekaran; Li, Yi-Shin; Chang, Nen-Chung; Huang, Shih-Yi; Hsieh, Cheng-Ying

2018-04-01

Vascular smooth muscle cell (VSMC) proliferation plays a major role in the progression of vascular diseases. In the present study, we established the efficacy and the mechanisms of action of hinokitiol, a tropolone derivative found in Chamaecyparis taiwanensis , Cupressaceae, in relation to platelet-derived growth factor-BB (PDGF-BB) and serum-dependent VSMC proliferation. Primary cultured rat VSMCs were pre-treated with hinokitiol and then stimulated by PDGF-BB (10 ng/ml) or serum (10% fetal bovine serum). Cell proliferation and cytotoxicity were determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and lactose dehydrogenase assay, respectively. The degree of DNA synthesis was evaluated by BrdU-incorporation measurements and observed using confocal microscopy. Immunoblotting was utilized to determine the protein level of p-extracellular signal-regulated kinase (ERK) 1/2, p-Akt, p-phosphoinositide 3-kinase (PI3K), p-Janus kinase 2 (JAK2), p-p53, and p21 Cip1 . The promoter activity of p21 and p53 activity were measured by dual luciferase reporter assay. Treatment with hinokitiol (1-10 μM) inhibited PDGF-BB and serum-induced VSMC proliferation and DNA synthesis in a concentration-dependent manner. Cytotoxicity was not observed in hinokitiol-treated VSMCs at the studied concentrations. Pre-incubation of VSMCs with hinokitiol did not alter PDGF-BB-induced phosphorylation of ERK1/2, Akt, PI3K or JAK2. Interestingly, hinokitiol induced promoter activity of p21 and p21 protein expression in VSMCs. Furthermore, hinokitiol augmented p53 protein phosphorylation and subsequently led to enhanced p53 activity. These data suggest that the anti-proliferative effects of hinokitiol in VSMCs may be mediated by activation of p21 and p53 signaling pathways, and it may contribute to the prevention of vascular diseases associated with VSMC proliferation.

Inhibitory effect of PDGF-BB and serum-stimulated responses in vascular smooth muscle cell proliferation by hinokitiol via up-regulation of p21 and p53

PubMed Central

Li, Jiun-Yi; Liu, Chun-Ping; Shiao, Wei-Cheng; Jayakumar, Thanasekaran; Li, Yi-Shin; Chang, Nen-Chung

2018-01-01

Introduction Vascular smooth muscle cell (VSMC) proliferation plays a major role in the progression of vascular diseases. In the present study, we established the efficacy and the mechanisms of action of hinokitiol, a tropolone derivative found in Chamaecyparis taiwanensis, Cupressaceae, in relation to platelet-derived growth factor-BB (PDGF-BB) and serum-dependent VSMC proliferation. Material and methods Primary cultured rat VSMCs were pre-treated with hinokitiol and then stimulated by PDGF-BB (10 ng/ml) or serum (10% fetal bovine serum). Cell proliferation and cytotoxicity were determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and lactose dehydrogenase assay, respectively. The degree of DNA synthesis was evaluated by BrdU-incorporation measurements and observed using confocal microscopy. Immunoblotting was utilized to determine the protein level of p-extracellular signal-regulated kinase (ERK) 1/2, p-Akt, p-phosphoinositide 3-kinase (PI3K), p-Janus kinase 2 (JAK2), p-p53, and p21Cip1. The promoter activity of p21 and p53 activity were measured by dual luciferase reporter assay. Results Treatment with hinokitiol (1–10 μM) inhibited PDGF-BB and serum-induced VSMC proliferation and DNA synthesis in a concentration-dependent manner. Cytotoxicity was not observed in hinokitiol-treated VSMCs at the studied concentrations. Pre-incubation of VSMCs with hinokitiol did not alter PDGF-BB-induced phosphorylation of ERK1/2, Akt, PI3K or JAK2. Interestingly, hinokitiol induced promoter activity of p21 and p21 protein expression in VSMCs. Furthermore, hinokitiol augmented p53 protein phosphorylation and subsequently led to enhanced p53 activity. Conclusions These data suggest that the anti-proliferative effects of hinokitiol in VSMCs may be mediated by activation of p21 and p53 signaling pathways, and it may contribute to the prevention of vascular diseases associated with VSMC proliferation. PMID:29765446

Effect of paricalcitol and GcMAF on angiogenesis and human peripheral blood mononuclear cell proliferation and signaling.

PubMed

Pacini, Stefania; Morucci, Gabriele; Punzi, Tiziana; Gulisano, Massimo; Ruggiero, Marco; Amato, Marcello; Aterini, Stefano

2012-01-01

In addition to its role in calcium homeostasis and bone mineralization, vitamin D is involved in immune defence, cardiovascular function, inflammation and angiogenesis, and these pleiotropic effects are of interested in the treatment of chronic kidney disease. Here we investigated the effects of paricalcitol, a nonhypercalcemic vitamin D analogue, on human peripheral blood mononuclear cell proliferation and signaling, and on angiogenesis. These effects were compared with those of a known inhibitor of angiogenesis pertaining to the vitamin D axis, the vitamin D-binding protein-derived Gc-macrophage activating factor (GcMAF). Since the effects of vitamin D receptor agonists are associated with polymorphisms of the gene coding for the receptor, we measured the effects of both compounds on mononuclear cells harvested from subjects harboring different BsmI polymorphisms. Paricalcitol inhibited mononuclear cell viability with the bb genotype showing the highest effect. GcMAF, on the contrary, stimulated cell proliferation, with the bb genotype showing the highest stimulatory effect. Both compounds stimulated 3'-5'-cyclic adenosine monophosphate formation in mononuclear cells with the highest effect on the bb genotype. Paricalcitol and GcMAF inhibited the angiogenesis induced by proinflammatory prostaglandin E1. Polymorphisms of the vitamin D receptor gene, known to be associated with the highest responses to vitamin D receptor agonists, are also associated with the highest responses to GcMAF. These results highlight the role of the vitamin D axis in chronic kidney disease, an axis which includes vitamin D, its receptor and vitamin D-binding protein-derived GcMAF.

Squamous epithelium formation in the respiratory intestine of the bronze Corydoras Corydoras aeneus (Callichthyidae Teleostei).

PubMed

Satora, Leszek; Kozioł, Katarzyna; Zebrowski, Jacek

2017-06-01

Accessory respiratory organs in fish exhibit great diversity but share the presence of numerous capillaries covered by a simple squamous epithelium. The adoption of the intestine for respiratory function needs certain special modifications. In this study, we explored immunohistochemical and metabolic fingerprint features that could underlay this adaptation in bronze corydoras Corydoras aeneus. Immunohistochemical localization of the cytoplasmic domain of epidermal growth factor receptor (EGFR) in the respiratory part of intestine demonstrated a strong positive immunoreaction in epithelial cells and connective tissue. Fourier Transfer Infrared (FTIR) spectroscopy coupled with chemometrics discriminated between anterior and posterior region of intestine in terms of secondary structure of proteins and the abundance of p-cresol and other phenolics. The latter were reduced in the posterior part of intestine, indicating the cessation of digestive function in this region. It has been suggested that aquatic hypoxia via endocrine cells (hypoxia-sensitive) activate EGFR, which induce proliferation of squamous epithelial cells, thereby enabling gas diffusion in the posterior part of intestine. It seems that hypoxia and normoxia are opposed conditions adjusting the production of squamous epithelial cells in this intestine. The physiological role of EGFR in the respiratory intestine of bronze corydoras is of interest not only from an evolutionary aspect but also in terms of a potential model for observations process proliferation squamous epithelial cells. Future investigations on the molecular responses to different water oxygen levels in air-breathing bronze corydoras fish are required to clarify the mechanism responsible for squamous cell proliferation. Copyright © 2017 Elsevier GmbH. All rights reserved.

Supporting aspartate biosynthesis is an essential function of respiration in proliferating cells

PubMed Central

Sullivan, Lucas B.; Gui, Dan Y.; Hosios, Aaron M.; Bush, Lauren N.; Freinkman, Elizaveta; Vander Heiden, Matthew G.

2015-01-01

Summary Mitochondrial respiration is important for cell proliferation, however the specific metabolic requirements fulfilled by respiration to support proliferation have not been defined. Here we show that a major role of respiration in proliferating cells is to provide electron acceptors for aspartate synthesis. This finding is consistent with the observation that cells lacking a functional respiratory chain are auxotrophic for pyruvate, which serves as an exogenous electron acceptor. Further, the pyruvate requirement can be fulfilled with an alternative electron acceptor, alpha-ketobutyrate, which provides cells neither carbon nor ATP. Alpha-ketobutyrate restores proliferation when respiration is inhibited, suggesting that an alternative electron acceptor can substitute for respiration to support proliferation. We find that electron acceptors are limiting for producing aspartate, and supplying aspartate enables proliferation of respiration deficient cells in the absence of exogenous electron acceptors. Together, these data argue a major function of respiration in proliferating cells is to support aspartate synthesis. PMID:26232225

Neuronal models for evaluation of proliferation in vitro using high content screening.

PubMed

Mundy, William R; Radio, Nicholas M; Freudenrich, Theresa M

2010-04-11

In vitro test methods can provide a rapid approach for the screening of large numbers of chemicals for their potential to produce toxicity (hazard identification). In order to identify potential developmental neurotoxicants, a battery of in vitro tests for neurodevelopmental processes such as cell proliferation, differentiation, growth, and synaptogenesis has been proposed. The development of in vitro approaches for toxicity testing will require choosing a model system that is appropriate to the endpoint of concern. This study compared several cell lines as models for neuronal proliferation. The sensitivities of neuronal cell lines derived from three species (PC12, rat; N1E-115, mouse; SH-SY5Y, human) to chemicals known to affect cell proliferation were assessed using a high content screening system. After optimizing conditions for cell growth in 96-well plates, proliferation was measured as the incorporation of 5-bromo-2'-deoxyuridine (BrdU) into replicating DNA during S phase. BrdU-labeled cells were detected by immunocytochemistry and cell counts were obtained using automated image acquisition and analysis. The three cell lines showed approximately 30-40% of the population in S phase after a 4h pulse of BrdU. Exposure to the DNA polymerase inhibitor aphidicolin for 20 h prior to the 4h pulse of BrdU significantly decreased proliferation in all three cell lines. The sensitivities of the cell lines were compared by exposure to eight chemicals known to affect proliferation (positive controls) and determination of the concentration inhibiting proliferation by 50% of control (I(50)). PC12 cells were the most sensitive to chemicals; 6 out of 8 chemicals (aphidicolin, cadmium, cytosine arabinoside, dexamethasone, 5-fluorouracil, and methylmercury) inhibited proliferation at the concentrations tested. SH-SY5Y cells were somewhat less sensitive to chemical effects, with five out of eight chemicals inhibiting proliferation; dexamethasone had no effect, and cadmium inhibited proliferation only at concentrations that decreased cell viability. Data from the N1E-115 cell line was extremely variable between experiments, and only 4 out of 8 chemicals resulted in inhibition of proliferation. Chemicals that had not been previously shown to alter proliferation (negative controls) did not affect proliferation or cell viability in any cell line. The results show that high content screening can be used to rapidly assess chemical effects on proliferation. Three neuronal cell lines exhibited differential sensitivity to the effect of chemicals on this endpoint, with PC12 cells being the most sensitive to inhibition of proliferation. Published by Elsevier Ireland Ltd.

Altered MENIN expression disrupts the MAFA differentiation pathway in insulinoma.

PubMed

Hamze, Z; Vercherat, C; Bernigaud-Lacheretz, A; Bazzi, W; Bonnavion, R; Lu, J; Calender, A; Pouponnot, C; Bertolino, P; Roche, C; Stein, R; Scoazec, J Y; Zhang, C X; Cordier-Bussat, M

2013-12-01

The protein MENIN is the product of the multiple endocrine neoplasia type I (MEN1) gene. Altered MENIN expression is one of the few events that are clearly associated with foregut neuroendocrine tumours (NETs), classical oncogenes or tumour suppressors being not involved. One of the current challenges is to understand how alteration of MENIN expression contributes to the development of these tumours. We hypothesised that MENIN might regulate factors maintaining endocrine-differentiated functions. We chose the insulinoma model, a paradigmatic example of well-differentiated pancreatic NETs, to study whether MENIN interferes with the expression of v-MAF musculoaponeurotic fibrosarcoma oncogene homologue A (MAFA), a master glucose-dependent transcription factor in differentiated β-cells. Immunohistochemical analysis of a series of human insulinomas revealed a correlated decrease in both MENIN and MAFA. Decreased MAFA expression resulting from targeted Men1 ablation was also consistently observed in mouse insulinomas. In vitro analyses using insulinoma cell lines showed that MENIN regulated MAFA protein and mRNA levels, and bound to Mafa promoter sequences. MENIN knockdown concomitantly decreased mRNA expression of both Mafa and β-cell differentiation markers (Ins1/2, Gck, Slc2a2 and Pdx1) and, in parallel, increased the proliferation rate of tumours as measured by bromodeoxyuridine incorporation. Interestingly, MAFA knockdown alone also increased proliferation rate but did not affect the expression of candidate proliferation genes regulated by MENIN. Finally, MENIN variants with missense mutations detected in patients with MEN1 lost the WT MENIN properties to regulate MAFA. Together, our findings unveil a previously unsuspected MENIN/MAFA connection regarding control of the β-cell differentiation/proliferation balance, which could contribute to tumorigenesis.

The effects of caffeine on wound healing.

PubMed

Ojeh, Nkemcho; Stojadinovic, Olivera; Pastar, Irena; Sawaya, Andrew; Yin, Natalie; Tomic-Canic, Marjana

2016-10-01

The purine alkaloid caffeine is a major component of many beverages such as coffee and tea. Caffeine and its metabolites theobromine and xanthine have been shown to have antioxidant properties. Caffeine can also act as adenosine-receptor antagonist. Although it has been shown that adenosine and antioxidants promote wound healing, the effect of caffeine on wound healing is currently unknown. To investigate the effects of caffeine on processes involved in epithelialisation, we used primary human keratinocytes, HaCaT cell line and ex vivo model of human skin. First, we tested the effects of caffeine on cell proliferation, differentiation, adhesion and migration, processes essential for normal wound epithelialisation and closure. We used 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) proliferation assay to test the effects of seven different caffeine doses ranging from 0·1 to 5 mM. We found that caffeine restricted cell proliferation of keratinocytes in a dose-dependent manner. Furthermore, scratch wound assays performed on keratinocyte monolayers indicated dose-dependent delays in cell migration. Interestingly, adhesion and differentiation remained unaffected in monolayer cultures treated with various doses of caffeine. Using a human ex vivo wound healing model, we tested topical application of caffeine and found that it impedes epithelialisation, confirming in vitro data. We conclude that caffeine, which is known to have antioxidant properties, impedes keratinocyte proliferation and migration, suggesting that it may have an inhibitory effect on wound healing and epithelialisation. Therefore, our findings are more in support of a role for caffeine as adenosine-receptor antagonist that would negate the effect of adenosine in promoting wound healing. © 2014 The Authors. International Wound Journal © 2014 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Roles of hepatocyte and myeloid CXC chemokine receptor-2 in liver recovery and regeneration after ischemia/reperfusion in mice.

PubMed

Van Sweringen, Heather L; Sakai, Nozomu; Quillin, Ralph C; Bailey, Jeff; Schuster, Rebecca; Blanchard, John; Goetzman, Holly; Caldwell, Charles C; Edwards, Michael J; Lentsch, Alex B

2013-01-01

Previous studies have demonstrated the significance of signaling through the CXC chemokine receptor-2 (CXCR2) receptor in the process of recovery and regeneration of functional liver mass after hepatic ischemia/reperfusion (I/R). CXCR2 is constitutively expressed on both neutrophils and hepatocytes; however, the cell-specific roles of this receptor are unknown. In the present study, chimeric mice were created through bone marrow transplantation (BMT) using wild-type and CXCR2-knockout mice, yielding selective expression of CXCR2 on hepatocytes (Hep) and/or myeloid cells (My) in the following combinations: Hep+/My+; Hep-/My+; Hep+/My-; and Hep-/My-. These tools allowed us to assess the contributions of myeloid and hepatocyte CXCR2 in the recovery of the liver after I/R injury. Flow cytometry confirmed the adoption of the donor phenotype in neutrophils. Interestingly, Kupffer cells from all chimeras lacked CXCR2 expression. Recovery/regeneration of hepatic parenchyma was assessed by histologic assessment and measurement of hepatocyte proliferation. CXCR2(Hep+/My+) mice showed the least amount of liver recovery and hepatocyte proliferation, whereas CXCR2(Hep-/My-) mice had the greatest liver recovery and hepatocyte proliferation. CXCR2(Hep+/My-) mice had enhanced liver recovery, with hepatocyte proliferation similar to CXCR2(Hep-/My-) mice. Myeloid expression of CXCR2 directly regulated CXC chemokine expression levels after hepatic I/R, such that mice lacking myeloid CXCR2 had markedly increased chemokine expression, compared with mice expressing CXCR2 on myeloid cells. The data suggest that CXCR2 on myeloid cells is the predominant regulator of liver recovery and regeneration after I/R injury, whereas hepatocyte CXCR2 plays a minor, secondary role. These findings suggest that myeloid cell-directed therapy may significantly affect liver regeneration after liver resection or transplantation. Copyright © 2012 American Association for the Study of Liver Diseases.

Free fatty acids block glucose-induced β-cell proliferation in mice by inducing cell cycle inhibitors p16 and p18.

PubMed

Pascoe, Jordan; Hollern, Douglas; Stamateris, Rachel; Abbasi, Munira; Romano, Lia C; Zou, Baobo; O'Donnell, Christopher P; Garcia-Ocana, Adolfo; Alonso, Laura C

2012-03-01

Pancreatic β-cell proliferation is infrequent in adult humans and is not increased in type 2 diabetes despite obesity and insulin resistance, suggesting the existence of inhibitory factors. Free fatty acids (FFAs) may influence proliferation. In order to test whether FFAs restrict β-cell proliferation in vivo, mice were intravenously infused with saline, Liposyn II, glucose, or both, continuously for 4 days. Lipid infusion did not alter basal β-cell proliferation, but blocked glucose-stimulated proliferation, without inducing excess β-cell death. In vitro exposure to FFAs inhibited proliferation in both primary mouse β-cells and in rat insulinoma (INS-1) cells, indicating a direct effect on β-cells. Two of the fatty acids present in Liposyn II, linoleic acid and palmitic acid, both reduced proliferation. FFAs did not interfere with cyclin D2 induction or nuclear localization by glucose, but increased expression of inhibitor of cyclin dependent kinase 4 (INK4) family cell cycle inhibitors p16 and p18. Knockdown of either p16 or p18 rescued the antiproliferative effect of FFAs. These data provide evidence for a novel antiproliferative form of β-cell glucolipotoxicity: FFAs restrain glucose-stimulated β-cell proliferation in vivo and in vitro through cell cycle inhibitors p16 and p18. If FFAs reduce proliferation induced by obesity and insulin resistance, targeting this pathway may lead to new treatment approaches to prevent diabetes.

Living together in biofilms: the microbial cell factory and its biotechnological implications.

PubMed

Berlanga, Mercedes; Guerrero, Ricardo

2016-10-01

In nature, bacteria alternate between two modes of growth: a unicellular life phase, in which the cells are free-swimming (planktonic), and a multicellular life phase, in which the cells are sessile and live in a biofilm, that can be defined as surface-associated microbial heterogeneous structures comprising different populations of microorganisms surrounded by a self-produced matrix that allows their attachment to inert or organic surfaces. While a unicellular life phase allows for bacterial dispersion and the colonization of new environments, biofilms allow sessile cells to live in a coordinated, more permanent manner that favors their proliferation. In this alternating cycle, bacteria accomplish two physiological transitions via differential gene expression: (i) from planktonic cells to sessile cells within a biofilm, and (ii) from sessile to detached, newly planktonic cells. Many of the innate characteristics of biofilm bacteria are of biotechnological interest, such as the synthesis of valuable compounds (e.g., surfactants, ethanol) and the enhancement/processing of certain foods (e.g., table olives). Understanding the ecology of biofilm formation will allow the design of systems that will facilitate making products of interest and improve their yields.

Homeostatic action of adenosine A3 and A1 receptor agonists on proliferation of hematopoietic precursor cells.

PubMed

Hofer, Michal; Pospísil, Milan; Znojil, Vladimír; Holá, Jirina; Streitová, Denisa; Vacek, Antonín

2008-07-01

Two adenosine receptor agonists, N6-(3-iodobenzyl)adenosine-5'-N-methyluronamide (IB-MECA) and N6-cyclopentyladenosine (CPA), which selectively activate adenosine A3 and A1 receptors, respectively, were tested for their ability to influence proliferation of granulocytic and erythroid cells in femoral bone marrow of mice using morphological criteria. Agonists were given intraperitoneally to mice in repeated isomolar doses of 200 nmol/kg. Three variants of experiments were performed to investigate the action of the agonists under normal resting state of mice and in phases of cell depletion and subsequent regeneration after treatment with the cytotoxic drug 5-fluorouracil. In the case of granulopoiesis, IB-MECA 1) increased by a moderate but significant level proliferation of cells under normal resting state; 2) strongly increased proliferation of cells in the cell depletion phase; but 3) did not influence cell proliferation in the regeneration phase. CPA did not influence cell proliferation under normal resting state and in the cell depletion phase, but strongly suppressed the overshooting cell proliferation in the regeneration phase. The stimulatory effect of IB-MECA on cell proliferation of erythroid cells was observed only when this agonist was administered during the cell depletion phase. CPA did not modulate erythroid proliferation in any of the functional states investigated, probably due to the lower demand for cell production as compared with granulopoiesis. The results indicate opposite effects of the two adenosine receptor agonists on proliferation of hematopoietic cells and suggest the plasticity and homeostatic role of the adenosine receptor expression.

Homeobox A7 stimulates breast cancer cell proliferation by up-regulating estrogen receptor-alpha

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

Zhang, Yu; Department of Obstetrics and Gynaecology, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia V5Z 4H4; Cheng, Jung-Chien

2013-11-01

Highlights: •HOXA7 regulates MCF7 cell proliferation. •HOXA7 up-regulates ERα expression. •HOXA7 mediates estrogen-induced MCF7 cell proliferation. -- Abstract: Breast cancer is the most common hormone-dependent malignancy in women. Homeobox (HOX) transcription factors regulate many cellular functions, including cell migration, proliferation and differentiation. The aberrant expression of HOX genes has been reported to be associated with human reproductive cancers. Estradiol (E2) and its nuclear receptors, estrogen receptor (ER)-alpha and ER-beta, are known to play critical roles in the regulation of breast cancer cell growth. However, an understanding of the potential relationship between HOXA7 and ER in breast cancer cells is limited.more » In this study, our results demonstrate that knockdown of HOXA7 in MCF7 cells significantly decreased cell proliferation and ERα expression. In addition, HOXA7 knockdown attenuated E2-induced cell proliferation as well as progesterone receptor (PR) expression. The stimulatory effects of E2 on cell proliferation and PR expression were abolished by co-treatment with ICI 182780, a selective ERα antagonist. In contrast, overexpression of HOXA7 significantly stimulated cell proliferation and ERα expression. Moreover, E2-induced cell proliferation, as well as PR expression, was enhanced by the overexpression of HOXA7. Neither knockdown nor overexpression of HOXA7 affected the ER-beta levels. Our results demonstrate a novel mechanistic role for HOXA7 in modulating breast cancer cell proliferation via regulation of ERα expression. This finding contributes to our understanding of the role HOXA7 plays in regulating the proliferation of ER-positive cancer cells.« less

Development of novel microfluidic platforms for neural stem cell research

NASA Astrophysics Data System (ADS)

Chung, Bonggeun

This dissertation describes the development and characterization of novel microfluidic platforms to study proliferation, differentiation, migration, and apoptosis of neural stem cells (NSCs). NSCs hold tremendous promise for fundamental biological studies and cell-based therapies in human disorders. NSCs are defined as cells that can self-renew yet maintain the ability to generate the three principal cell types of the central nervous system such as neurons, astrocytes, and oligodendrocytes. NSCs therefore have therapeutic possibilities in multiple neurodevelopmental and neurodegenerative diseases. Despite their promise, cell-based therapies are limited by the inability to precisely control their behavior in culture. Compared to traditional culture tools, microfluidic platforms can provide much greater control over cell microenvironments and optimize proliferation and differentiation conditions of cells exposed to combinatorial mixtures of growth factors. Human NSCs were cultured for more than 1 week in the microfluidic device while constantly exposed to a continuous gradient of a growth factor mixture. NSCs proliferated and differentiated in a graded and proportional fashion that varied directly with growth factor concentration. In parallel to the study of growth and differentiation of NSCs, we are interested in proliferation and apoptosis of mouse NSCs exposed to morphogen gradients. Morphogen gradients are fundamental to animal brain development. Nonetheless, much controversy remains about the mechanisms by which morphogen gradients act on the developing brain. To overcome limitations of in-vitro models of gradients, we have developed a hybrid microfluidic platform that can mimic morphogen gradient profiles. Bone morphogenetic protein (BMP) activity in the developing cortex is graded and cortical NSC responses to BMPs are highly dependent on concentration and gradient slope of BMPs. To make novel microfluidic devices integrated with multiple functions, we have also developed a microfluidic multi-injector (MMI) that can generate temporal and spatial concentration gradients. MMI consists of fluidic channels and control channels with pneumatically actuated on-chip barrier valves. Repetitive actuations of on-chip valves control pulsatile release of solution that establishes microscopic chemical gradients. The development of novel gradient-generating microfluidic platforms will help in advancing our understanding of brain development and provide a versatile tool with basic and applied studies in stem cell biology.

Pokemon/miR-137 auto-regulatory circuit promotes the progression of renal carcinoma.

PubMed

Wang, Lihui; Li, Qi; Ye, Zhuo; Qiao, Baoping

2018-04-19

Renal carcinoma greatly threatens human health, but the involved molecular mechanisms are far from complete understanding. As a master oncogene driving the initiation of many other cancers, Pokemon has not been established to be associated with renal cancer. Our data revealed that Pokemon is highly expressed in renal carcinoma specimen and cell lines, compared with normal cells. The silencing of Pokemon suppressed the proliferation and invasion of renal cancer cells. Pokemon overexpression rendered normal cells with higher proliferation rates and invasiveness. Animal study further confirmed the role of Pokemon in the growth of renal carcinoma. Moreover, miR-137 was identified to negatively regulate the expression of Pokemon, and its abundance is inversely correlated with that of Pokemon in renal carcinoma specimen and cell lines. Pokemon overexpression may be induced by miR-137 downregulation. Interestingly, Pokemon can also suppress miR-137 expression by binding to its recognition site within miR-137 promoter region. Taken together, we identified an autoregulatory loop consisting of Pokemon and miR-137 in gastric cancers, and targeting this pathway may be an effective strategy for renal carcinoma cancer therapy.

Combinatorial effect of curcumin with docetaxel modulates apoptotic and cell survival molecules in prostate cancer

PubMed Central

Banerjee, Saswati; Singh, Santosh K.; Chowdhury, Indrajit; Lillard, James W.; Singh, Rajesh

2017-01-01

Docetaxel is the most commonly used chemotherapeutic agent to target androgen signaling in metastatic prostate cancer (PCa); however, prolonged treatment with docetaxel results in drug-resistant cancer cells. Combination therapies have the potential of increasing the effectiveness of drug treatment as well as decreasing the side effects. Curcumin is a nontoxic organic compound with multifaceted chemopreventive potential. In this study, we evaluated whether curcumin can reinforce the effect of docetaxel on PCa cells. The PCa cell lines DU145 and PC3 were treated with curcumin and docetaxel alone or in combination. After completion of the treatment cell proliferation and the expression of pro-survival and anti-apoptotic markers and the signaling molecules were analyzed. The combined treatment of curcumin and docetaxel inhibited the proliferation and induced apoptosis significantly higher than the curcumin and docetaxel-treated group alone. Interestingly, the combined treatment with curcumin and docetaxel modulates the expression of RTKs, PI3K, phospho-AKT, NF-kappa B, p53, and COX-2. These results suggest that curcumin can be a potential therapeutic contender in enhancing the efficacy of docetaxel in PCa treatment. PMID:28199187

Regulation and spatial organization of PCNA in Trypanosoma brucei

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

Kaufmann, Doris; Gassen, Alwine; Maiser, Andreas

2012-03-23

Highlights: Black-Right-Pointing-Pointer Characterization of the proliferating cell nuclear antigen in Trypanosoma brucei (TbPCNA). Black-Right-Pointing-Pointer TbPCNA is a suitable marker to detect replication in T. brucei. Black-Right-Pointing-Pointer TbPCNA distribution and regulation is different compared to closely related parasites T. cruzi and Leishmania donovani. -- Abstract: As in most eukaryotic cells, replication is regulated by a conserved group of proteins in the early-diverged parasite Trypanosoma brucei. Only a few components of the replication machinery have been described in this parasite and regulation, sub-nuclear localization and timing of replication are not well understood. We characterized the proliferating cell nuclear antigen in T. bruceimore » (TbPCNA) to establish a spatial and temporal marker for replication. Interestingly, PCNA distribution and regulation is different compared to the closely related parasites Trypanosoma cruzi and Leishmania donovani. TbPCNA foci are clearly detectable during S phase of the cell cycle but in contrast to T. cruzi they are not preferentially located at the nuclear periphery. Furthermore, PCNA seems to be degraded when cells enter G2 phase in T. brucei suggesting different modes of replication regulation or functions of PCNA in these closely related eukaryotes.« less

TC-1 Overexpression Promotes Cell Proliferation in Human Non-Small Cell Lung Cancer that Can Be Inhibited by PD173074

PubMed Central

Zhang, Na; Bai, Guangzhen; Zhong, Daixing; Su, Kai; Liu, Boya; Li, Xiaofei; Wang, Yunjie; Wang, Xiaoping

2014-01-01

Thyroid cancer-1 (TC-1), a natively disordered protein, is widely expressed in vertebrates and overexpressed in many kinds of tumors. However, its exact role and regulation mechanism in human non-small cell lung cancer (NSCLC) are still unclear. In the present study, we found that TC-1 is highly expressed in NSCLC and that its aberrant expression is strongly associated with NSCLC cell proliferation. Exogenous TC-1 overexpression promotes cell proliferation, accelerates the cell G1-to-S-phase transition, and reduces apoptosis in NSCLC. The knockdown of TC-1, however, inhibits NSCLC cell proliferation, cycle transition, and apoptosis resistance. Furthermore, we also demonstrated that PD173074, which functions as an inhibitor of the TC-1 in NSCLC, decreases the expression of TC-1 and inhibits TC-1 overexpression mediated cell proliferation in vitro and in vivo. Nevertheless, the inhibition function of PD173074 on NSCLC cell proliferation was eliminated in cells with TC-1 knockdown. These results suggest that PD173074 plays a significant role in TC-1 overexpression mediated NSCLC cell proliferation and may be a potential intervention target for the prevention of cell proliferation in NSCLC. PMID:24941347

ΔNp63α is an oncogene that induces Lsh expression and promotes stem-like proliferation

PubMed Central

Keyes, William M.; Pecoraro, Matteo; Aranda, Victoria; Vernersson-Lindahl, Emma; Li, Wangzhi; Vogel, Hannes; Guo, Xuecui; Garcia, Elvin L.; Michurina, Tatyana V.; Enikolopov, Grigori; Muthuswamy, Senthil K.; Mills, Alea A.

2014-01-01

SUMMARY The p53 homolog p63 is essential for development, yet its role in cancer is not clear. We discovered that p63 deficiency evokes the tumor suppressive mechanism of cellular senescence, causing a striking absence of stratified epithelia such as the skin. Here we identify the predominant p63 isoform, ΔNp63α, as a protein that bypasses oncogene induced senescence to drive tumorigenesis in vivo. Interestingly, bypass of senescence promotes stem-like proliferation and maintains survival of the keratin 15-positive stem cell population. Furthermore, we identify the chromatin remodeling protein Lsh as a new target of ΔNp63α that is an essential mediator of senescence bypass. These findings indicate that ΔNp63α is an oncogene that cooperates with Ras to promote tumor-initiating stem-like proliferation, and suggest that Lsh-mediated chromatin remodeling events are critical to this process. PMID:21295273

Dose-related cell proliferation in medaka (Oryzias latipes) after N-nitrosodiethylamine exposure

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

Ortego, L.S.; Hawkins, W.E.; Walker, W.W.

1994-12-31

Cell proliferation is important in toxic and carcinogenic mechanisms. Carcinogens such as N-nitrosodiethylamine (DEN) that cause necrotizing injury stimulate cell proliferation as part of an injury-repair mechanism. A stimulus to cell division in an organ with a low rate of cell division, such as the liver, may initiate or enhance the carcinogenicity of a chemical. The authors examined the effect of DEN exposure on cell proliferation in the liver of medaka (Oryzias latipes). Two age groups (6 and 56 days post-hatch) were exposed to DEN continuously at 5 doses (0.0, 2.5, 5.0, 10.0, and 20.0 ppm) for 28 days. Cellmore » proliferation was measured using the proliferating cell nuclear antigen (PCNA) assay two months post-initiation of DEN exposure. The assay involves monoclonal antibody detection of PCNA, an auxiliary protein of DNA polymerase delta which is, expressed during cell division. Results suggested that cell proliferation paralleled the DEN dose and that age at initiation of exposure did not affect this relationship. The increase in cell proliferation appeared to be a sustained response from that initiated during DEN exposure. The study suggests that cell proliferation in medaka is an important component in carcinogenesis and is related to carcinogen exposure dose.« less

Obesity Determines the Immunophenotypic Profile and Functional Characteristics of Human Mesenchymal Stem Cells From Adipose Tissue

PubMed Central

Pachón-Peña, Gisela; Serena, Carolina; Ejarque, Miriam; Petriz, Jordi; Duran, Xevi; Oliva-Olivera, W.; Simó, Rafael; Tinahones, Francisco J.

2016-01-01

Adipose tissue is a major source of mesenchymal stem cells (MSCs), which possess a variety of properties that make them ideal candidates for regenerative and immunomodulatory therapies. Here, we compared the immunophenotypic profile of human adipose-derived stem cells (hASCs) from lean and obese individuals, and explored its relationship with the apparent altered plasticity of hASCs. We also hypothesized that persistent hypoxia treatment of cultured hASCs may be necessary but not sufficient to drive significant changes in mature adipocytes. hASCs were obtained from subcutaneous adipose tissue of healthy, adult, female donors undergoing abdominal plastic surgery: lean (n = 8; body mass index [BMI]: 23 ± 1 kg/m2) and obese (n = 8; BMI: 35 ± 5 kg/m2). Cell surface marker expression, proliferation and migration capacity, and adipogenic differentiation potential of cultured hASCs at two different oxygen conditions were studied. Compared with lean-derived hASCs, obese-derived hASCs demonstrated increased proliferation and migration capacity but decreased lipid droplet accumulation, correlating with a higher expression of human leukocyte antigen (HLA)-II and cluster of differentiation (CD) 106 and lower expression of CD29. Of interest, adipogenic differentiation modified CD106, CD49b, HLA-ABC surface protein expression, which was dependent on the donor’s BMI. Additionally, low oxygen tension increased proliferation and migration of lean but not obese hASCs, which correlated with an altered CD36 and CD49b immunophenotypic profile. In summary, the differences observed in proliferation, migration, and differentiation capacity in obese hASCs occurred in parallel with changes in cell surface markers, both under basal conditions and during differentiation. Therefore, obesity is an important determinant of stem cell function independent of oxygen tension. Significance The obesity-related hypoxic environment may have latent effects on human adipose tissue-derived mesenchymal stem cells (hASCs) with potential consequences in mature cells. This study explores the immunophenotypic profile of hASCs obtained from lean and obese individuals and its potential relationship with the altered plasticity of hASCs observed in obesity. In this context, an altered pattern of cell surface marker expression in obese-derived hASCs in both undifferentiated and differentiated stages is demonstrated. Differences in proliferation, migration, and differentiation capacity of hASCs from obese adipose tissue correlated with alterations in cell surface expression. Remarkably, altered plasticity observed in obese-derived hASCs was maintained in the absence of hypoxia, suggesting that these cells might be obesity conditioned. PMID:26956208

Limited CD4+ T cell proliferation leads to preservation of CD4+ T cell counts in SIV-infected sooty mangabeys.

PubMed

Chan, Ming Liang; Petravic, Janka; Ortiz, Alexandra M; Engram, Jessica; Paiardini, Mirko; Cromer, Deborah; Silvestri, Guido; Davenport, Miles P

2010-12-22

Human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) infections result in chronic virus replication and progressive depletion of CD4+ T cells, leading to immunodeficiency and death. In contrast, 'natural hosts' of SIV experience persistent infection with high virus replication but no severe CD4+ T cell depletion, and remain AIDS-free. One important difference between pathogenic and non-pathogenic infections is the level of activation and proliferation of CD4+ T cells. We analysed the relationship between CD4+ T cell number and proliferation in HIV, pathogenic SIV in macaques, and non-pathogenic SIV in sooty mangabeys (SMs) and mandrills. We found that CD4+ T cell proliferation was negatively correlated with CD4+ T cell number, suggesting that animals respond to the loss of CD4+ T cells by increasing the proliferation of remaining cells. However, the level of proliferation seen in pathogenic infections (SIV in rhesus macaques and HIV) was much greater than in non-pathogenic infections (SMs and mandrills). We then used a modelling approach to understand how the host proliferative response to CD4+ T cell depletion may impact the outcome of infection. This modelling demonstrates that the rapid proliferation of CD4+ T cells in humans and macaques associated with low CD4+ T cell levels can act to 'fuel the fire' of infection by providing more proliferating cells for infection. Natural host species, on the other hand, have limited proliferation of CD4+ T cells at low CD4+ T cell levels, which allows them to restrict the number of proliferating cells susceptible to infection.

Limited CD4+ T cell proliferation leads to preservation of CD4+ T cell counts in SIV-infected sooty mangabeys

PubMed Central

Chan, Ming Liang; Petravic, Janka; Ortiz, Alexandra M.; Engram, Jessica; Paiardini, Mirko; Cromer, Deborah; Silvestri, Guido; Davenport, Miles P.

2010-01-01

Human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) infections result in chronic virus replication and progressive depletion of CD4+ T cells, leading to immunodeficiency and death. In contrast, ‘natural hosts’ of SIV experience persistent infection with high virus replication but no severe CD4+ T cell depletion, and remain AIDS-free. One important difference between pathogenic and non-pathogenic infections is the level of activation and proliferation of CD4+ T cells. We analysed the relationship between CD4+ T cell number and proliferation in HIV, pathogenic SIV in macaques, and non-pathogenic SIV in sooty mangabeys (SMs) and mandrills. We found that CD4+ T cell proliferation was negatively correlated with CD4+ T cell number, suggesting that animals respond to the loss of CD4+ T cells by increasing the proliferation of remaining cells. However, the level of proliferation seen in pathogenic infections (SIV in rhesus macaques and HIV) was much greater than in non-pathogenic infections (SMs and mandrills). We then used a modelling approach to understand how the host proliferative response to CD4+ T cell depletion may impact the outcome of infection. This modelling demonstrates that the rapid proliferation of CD4+ T cells in humans and macaques associated with low CD4+ T cell levels can act to ‘fuel the fire’ of infection by providing more proliferating cells for infection. Natural host species, on the other hand, have limited proliferation of CD4+ T cells at low CD4+ T cell levels, which allows them to restrict the number of proliferating cells susceptible to infection. PMID:20591864

Dual role of BMP signaling in the regulation of Drosophila intestinal stem cell self-renewal.

PubMed

Tian, Aiguo; Jiang, Jin

2017-10-02

Many adult organs including Drosophila adult midguts rely on resident stem cells to replenish damaged cells during tissue homeostasis and regeneration. Previous studies have shown that, upon injury, intestinal stem cells (ISCs) in the midguts can increase proliferation and lineage differentiation to meet the demand for tissue repair. Our recent study has demonstrated that, in response to certain injury, midguts can expand ISC population size as an additional regenerative mechanism. We found that injury elicited by bleomycin feeding or bacterial infection increased the production of two BMP ligands (Dpp and Gbb) in enterocytes (ECs), leading to elevated BMP signaling in progenitor cells that drove an expansion of ISCs by promoting their symmetric self-renewing division. Interestingly, we also found that BMP signaling in ECs inhibits the production of Dpp and Gbb, and that this negative feedback mechanism is required to reset ISC pool size to the homeostatic state. Our findings suggest that BMP signaling exerts two opposing influences on stem cell activity depending on where it acts: BMP signaling in progenitor cells promotes ISC self-renewal while BMP signaling in ECs restricts ISC self-renewal by preventing excessive production of BMP ligands. Our results further suggest that transient expansion of ISC population in conjunction with increasing ISC proliferation provides a more effective strategy for tissue regeneration.

Biocompatibility of tungsten disulfide inorganic nanotubes and fullerene-like nanoparticles with salivary gland cells.

PubMed

Goldman, Elisheva B; Zak, Alla; Tenne, Reshef; Kartvelishvily, Elena; Levin-Zaidman, Smadar; Neumann, Yoav; Stiubea-Cohen, Raluca; Palmon, Aaron; Hovav, Avi-Hai; Aframian, Doron J

2015-03-01

Impaired salivary gland (SG) function leading to oral diseases is relatively common with no adequate solution. Previously, tissue engineering of SG had been proposed to overcome this morbidity, however, not yet clinically available. Multiwall inorganic (tungsten disulfide [WS2]) nanotubes (INT-WS2) and fullerene-like nanoparticles (IF-WS2) have many potential medical applications. A yet unexplored venue application is their interaction with SG, and therefore, our aim was to test the biocompatibility of INT/IF-WS2 with the A5 and rat submandibular cells (RSC) SG cells. The cells were cultured and subjected after 1 day to different concentrations of INT-WS2 and were compared to control groups. Growth curves, trypan blue viability test, and carboxyfluorescein succinimidyl ester (CFSE) proliferation assay were obtained. Furthermore, cells morphology and interaction with the nanoparticles were observed by light microscopy, scanning electron microscopy and transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy. The results showed no significant differences in growth curves, proliferation kinetics, and viability between the groups compared. Moreover, no alterations were observed in the cell morphology. Interestingly, TEM images indicated that the nanoparticles are uptaken by the cells and accumulate in cytoplasmic vesicles. These results suggest promising future medical applications for these nanoparticles.

Biocompatibility of Tungsten Disulfide Inorganic Nanotubes and Fullerene-Like Nanoparticles with Salivary Gland Cells

PubMed Central

Goldman, Elisheva B.; Zak, Alla; Tenne, Reshef; Kartvelishvily, Elena; Levin-Zaidman, Smadar; Neumann, Yoav; Stiubea-Cohen, Raluca; Palmon, Aaron; Hovav, Avi-Hai

2015-01-01

Impaired salivary gland (SG) function leading to oral diseases is relatively common with no adequate solution. Previously, tissue engineering of SG had been proposed to overcome this morbidity, however, not yet clinically available. Multiwall inorganic (tungsten disulfide [WS2]) nanotubes (INT-WS2) and fullerene-like nanoparticles (IF-WS2) have many potential medical applications. A yet unexplored venue application is their interaction with SG, and therefore, our aim was to test the biocompatibility of INT/IF-WS2 with the A5 and rat submandibular cells (RSC) SG cells. The cells were cultured and subjected after 1 day to different concentrations of INT-WS2 and were compared to control groups. Growth curves, trypan blue viability test, and carboxyfluorescein succinimidyl ester (CFSE) proliferation assay were obtained. Furthermore, cells morphology and interaction with the nanoparticles were observed by light microscopy, scanning electron microscopy and transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy. The results showed no significant differences in growth curves, proliferation kinetics, and viability between the groups compared. Moreover, no alterations were observed in the cell morphology. Interestingly, TEM images indicated that the nanoparticles are uptaken by the cells and accumulate in cytoplasmic vesicles. These results suggest promising future medical applications for these nanoparticles. PMID:25366879

A Tumor Suppressor Gene Product, Platelet-Derived Growth Factor Receptor-Like Protein Controls Chondrocyte Proliferation and Differentiation.

PubMed

Kawata, Kazumi; Kubota, Satoshi; Eguchi, Takanori; Aoyama, Eriko; Moritani, Norifumi H; Oka, Morihiko; Kawaki, Harumi; Takigawa, Masaharu

2017-11-01

The platelet-derived growth factor receptor-like (PDGFRL) gene is regarded as a tumor suppressor gene. However, nothing is known about the molecular function of PDGFRL. In this study, we initially clarified its function in chondrocytes. Among all cell lines examined, the PDGFRL mRNA level was the highest in chondrocytic HCS-2/8 cells. Interestingly, the proliferation of chondrocytic HCS-2/8 cells was promoted by PDGFRL overexpression, whereas that of the breast cancer-derived MDA-MB-231 cells was inhibited. Of note, in PDGFRL-overexpressing HCS-2/8 cells, the expression of chondrocyte differentiation marker genes, SOX9, ACAN, COL2A1, COL10A1, and ALP, was decreased. Moreover, we confirmed the expression of PDGFRL mRNA in normal cartilage tissue and chondrocytes. Eventually, the expression of PDGFRL mRNA in condrocytes except in the case of hypertrophic chondrocytes was demonstrated in vivo and in vitro. These findings suggest that PDGFRL plays the different roles, depending upon cell types. Particularly, in chondrocytes, PDGFRL may play a new and important role which is distinct from the function previously reported. J. Cell. Biochem. 118: 4033-4044, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Maturation of monocyte derived dendritic cells with OK432 boosts IL-12p70 secretion and conveys strong T-cell responses

PubMed Central

2011-01-01

Background Design of tumour specific immunotherapies using the patients' own dendritic cells (DC) is a fast advancing scientific field. The functional qualities of the DC generated in vitro are critical, and today's gold standard for maturation is a cytokine cocktail consisting of IL-1β, IL-6, TNF-α and PGE2 generating cells lacking IL-12p70 production. OK432 is an immunotherapeutic agent derived from killed Streptococcus pyogenes that has been used clinically to treat malignant and benign neoplasms for decades. Methods In this study, we analysed the effects of OK432 on DC maturation, DC migration, cytokine and chemokine secretion as well as T-cell stimulatory capacity, and compared it to the cytokine cocktail alone and combinations of OK432 with the cytokine cocktail. Results OK432 induced a marked up-regulation of CD40 on the cell surface as well as a strong inflammatory response from the DC with significantly more secretion of 19 different cytokines and chemokines compared to the cytokine cocktail. Interestingly, secretion of IL-15 and IL-12p70 was detected at high concentrations after maturation of DC with OK432. However, the OK432 treated DC did not migrate as well as DC treated with cytokine cocktail in a transwell migration assay. During allogeneic T-cell stimulation OK432 treated DC induced proliferation of over 50 percent of CD4 and 30 percent of CD8 T-cells for more than two cell divisions, whereas cytokine cocktail treated DC induced proliferation of 12 and 11 percent of CD4 and CD8 T-cells, respectively. Conclusions The clinically approved compound OK432 has interesting properties that warrants its use in DC immunotherapy and should be considered as a potential immunomodulating agent in cancer immunotherapy. PMID:21208424

Biomacromolecule conjugated nanofiber scaffold for salivary gland tissue engineering

NASA Astrophysics Data System (ADS)

Jayarathanam, Kavitha

Xerostomia or dry mouth, resulting from loss of salivary gland secretion can be alleviated by tissue engineering approaches to restore glandular cell function. Engineering an artificial salivary gland structure requires closely mimicking the natural environment, both physically and functionally, to promote epithelial cell proliferation, monolayer formation and apico-basal polarization. While the physical structure of the salivary gland extracellular matrix (ECM) can be reconstructed using biocompatible nanofiber scaffolds, the chemical signals from ECM macromolecules are equally involved in the gland morphogenesis. In these glands, Hyaluronic acid (HA), a biomacromolecule that is a major component of the ECM, plays a crucial role in recruiting growth factors to improve cell viability and growth in these glands. Another molecule of interest that improved salivary epithelial cell viability and apico-basal differentiation is laminin, a major protein found in the basement membrane. We hypothesize that these biomacromolecules, when conjugated nanofiber scaffolds, will provide the essential chemical signals that promote cell viability, proliferation, polarity in the salivary cell line of interest. These morphological changes will in turn promote the secretory function (salivary production). The nanofiber scaffold consisting of poly(lactic-co-glycolic)acid is conjugated with HA using a polyethylene glycol (PEG) diamine crosslinker. This conjugation was confirmed using fluorescence spectrometry, water contact angle test and immunocytochemistry analysis using confocal microscopy. The effect of HA in promoting cell survival in-vitro was established with MTT assay using SIMS (mouse submandibular immortalized ductal SIMS cells) cells. The effect of HA in improving the apico - basal polarity of SIMS cells will be assessed. Chemical modification of synthetic nanopolymeric scaffolds with ECM molecules e.g., HA, laminin are the next step towards developing "smart scaffolds", that can be used to specifically induce proper salivary gland function. These scaffolds can potentially be used to provide a viable approach for creating future artificial tissue engineered glands.

miRNA-1297 induces cell proliferation by targeting phosphatase and tensin homolog in testicular germ cell tumor cells.

PubMed

Yang, Nian-Qin; Zhang, Jian; Tang, Qun-Ye; Guo, Jian-Ming; Wang, Guo-Min

2014-01-01

To investigate the role of miR-1297 and the tumor suppressor gene PTEN in cell proliferation of testicular germ cell tumors (TGCT). MTT assays were used to test the effect of miR-1297 on proliferation of the NCCIT testicular germ cell tumor cell line. In NCCIT cells, the expression of PTEN was assessed by Western blotting further. In order to confirm target association between miR-1297 and 3'-UTR of PTEN, a luciferase reporter activity assay was employed. Moreover, roles of PTEN in proliferation of NCCIT cells were evaluated by transfection of PTEN siRNA. Proliferation of NCCIT cells was promoted by miR-1297 in a concentration-dependent manner. In addition, miR-1297 could bind to the 3'-UTR of PTEN based on luciferase reporter activity assay, and reduced expression of PTEN at protein level was found. Proliferation of NCCIT cells was significantly enhanced after knockdown of PTEN by siRNA. miR-1297 as a potential oncogene could induce cell proliferation by targeting PTEN in NCCIT cells.

Cell density and N-cadherin interactions regulate cell proliferation in the sensory epithelia of the inner ear.

PubMed

Warchol, Mark E

2002-04-01

Sensory hair cells in the inner ears of nonmammalian vertebrates can regenerate after injury. In many species, replacement hair cells are produced by the proliferation of epithelial supporting cells. Thus, the ability of supporting cells to undergo renewed proliferation is a key determinant of regenerative ability. The present study used cultures of isolated inner ear sensory epithelia to identify cellular signals that regulate supporting cell proliferation. Small pieces of sensory epithelia from the chicken utricle were cultured in glass microwells. Under those conditions, cell proliferation was inversely related to local cell density. The signaling molecules N-cadherin, beta-catenin, and focal adhesion kinase were immunolocalized in the cultured epithelial cells, and high levels of phosphotyrosine immunoreactivity were present at cell-cell junctions and focal contacts of proliferating cells. Binding of microbeads coated with a function-blocking antibody to N-cadherin inhibited ongoing proliferation. The growth of epithelial cells was also affected by the density of extracellular matrix molecules. The results suggest that cell density, cell-cell contact, and the composition of the extracellular matrix may be critical influences on the regulation of sensory regeneration in the inner ear.

Sevoflurane suppresses proliferation by upregulating microRNA-203 in breast cancer cells.

PubMed

Liu, Jiaying; Yang, Longqiu; Guo, Xia; Jin, Guangli; Wang, Qimin; Lv, Dongdong; Liu, Junli; Chen, Qiu; Song, Qiong; Li, Baolin

2018-05-03

Rapid proliferation is one of the critical characteristics of breast cancer. However, the underlying regulatory mechanism of breast cancer cell proliferation is largely unclear. The present study indicated that sevoflurane, one of inhalational anesthetics, could significantly suppress breast cancer cell proliferation by arresting cell cycle at G1 phase. Notably, the rescue experiment indicated that miR-203 was upregulated by sevoflurane and mediated the function of sevoflurane on suppressing the breast cancer cell proliferation. The present study indicated the function of the sevoflurane/miR-203 signaling pathway on regulating breast cancer cell proliferation. These results provide mechanistic insight into how the sevoflurane/miR-203 signaling pathway supresses proliferation of breast cancer cells, suggesting the sevoflurane/miR-203 pathway may be a potential target in the treatment of breast cancer.

The influence of androgens, anti-androgens, and castration on cell proliferation in the jejunal and colonic crypt epithelia, and in dimethylhydrazine-induced adenocarcinoma of rat colon.

PubMed

Tutton, P J; Barkla, D H

1982-01-01

Androgenic hormones have previously been shown to promote cell proliferation in the small intestine of rat and androgen receptors have been demonstrated in carcinomata of the large intestine of rat. In this study the influence of testosterone and of castration on epithelial cell proliferation in the small intestine, the large intestine and in dimethylhydrazine-induced colonic tumours is compared. Cell proliferation in the small intestine and in colonic tumours was accelerated by testosterone treatment, and cell proliferation in colonic tumours, but not in the small intestine, was retarded following castration. Cell proliferation in colonic tumours was also inhibited by the anti-androgenic drug, Flutamide. Testosterone and castration each failed to influence cell proliferation in the colonic crypt epithelium of both normal and carcinogen-treated animals.

IL-7 splicing variant IL-7{delta}5 induces human breast cancer cell proliferation via activation of PI3K/Akt pathway

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

Pan, Deshun; Department of Pharmaceutical science, Guangdong Pharmaceutical University, Guangzhou, Guangdong; Liu, Bing

2012-06-15

Highlights: Black-Right-Pointing-Pointer This study confirms the role of IL-7{delta}5 in breast cancer cell proliferation. Black-Right-Pointing-Pointer IL-7{delta}5 promotes breast cancer cell proliferation and cell cycle progression. Black-Right-Pointing-Pointer IL-7{delta}5 promotes cell proliferation via activation of PI3K/Akt pathway. -- Abstract: Various tumor cells express interleukin 7 (IL-7) and IL-7 variants. IL-7 has been confirmed to stimulate solid tumor cell proliferation. However, the effect of IL-7 variants on tumor cell proliferation remains unclear. In this study, we evaluated the role of IL-7{delta}5 (an IL-7 variant lacking exon 5) on proliferation and cell cycle progression of human MDA-MB-231 and MCF-7 breast cancer cells. The resultsmore » showed that IL-7{delta}5 promoted cell proliferation and cell cycle progression from G1 phase to G2/M phase, associated with upregulation of cyclin D1 expression and the downregulation of p27{sup kip1} expression. Mechanistically, we found that IL-7{delta}5 induced the activation of Akt. Inhibition of PI3K/Akt pathway by LY294002 reversed the proliferation and cell cycle progression of MDA-MB-231 and MCF-7 cells induced by IL-7{delta}5. In conclusion, our findings demonstrate that IL-7{delta}5 variant induces human breast cancer cell proliferation and cell cycle progression via activation of PI3K/Akt pathway. Thus, IL-7{delta}5 may be a potential target for human breast cancer therapeutics intervention.« less

Inhibition of the pentose phosphate pathway by dichloroacetate unravels a missing link between aerobic glycolysis and cancer cell proliferation.

PubMed

De Preter, Géraldine; Neveu, Marie-Aline; Danhier, Pierre; Brisson, Lucie; Payen, Valéry L; Porporato, Paolo E; Jordan, Bénédicte F; Sonveaux, Pierre; Gallez, Bernard

2016-01-19

Glucose fermentation through glycolysis even in the presence of oxygen (Warburg effect) is a common feature of cancer cells increasingly considered as an enticing target in clinical development. This study aimed to analyze the link between metabolism, energy stores and proliferation rates in cancer cells. We found that cell proliferation, evaluated by DNA synthesis quantification, is correlated to glycolytic efficiency in six cancer cell lines as well as in isogenic cancer cell lines. To further investigate the link between glycolysis and proliferation, a pharmacological inhibitor of the pentose phosphate pathway (PPP) was used. We demonstrated that reduction of PPP activity decreases cancer cells proliferation, with a profound effect in Warburg-phenotype cancer cells. The crucial role of the PPP in sustaining cancer cells proliferation was confirmed using siRNAs against glucose-6-phosphate dehydrogenase, the first and rate-limiting enzyme of the PPP. In addition, we found that dichloroacetate (DCA), a new clinically tested compound, induced a switch of glycolytic cancer cells to a more oxidative phenotype and decreased proliferation. By demonstrating that DCA decreased the activity of the PPP, we provide a new mechanism by which DCA controls cancer cells proliferation.

AS160 controls eukaryotic cell cycle and proliferation by regulating the CDK inhibitor p21.

PubMed

Gongpan, Pianchou; Lu, Yanting; Wang, Fang; Xu, Yuhui; Xiong, Wenyong

2016-07-02

AS160 (TBC1D4) has been implicated in multiple biological processes. However, the role and the mechanism of action of AS160 in the regulation of cell proliferation remain unclear. In this study, we demonstrated that AS160 knockdown led to blunted cell proliferation in multiple cell types, including fibroblasts and cancer cells. The results of cell cycle analysis showed that these cells were arrested in the G1 phase. Intriguingly, this inhibition of cell proliferation and the cell cycle arrest caused by AS160 depletion were glucose independent. Moreover, AS160 silencing led to a marked upregulation of the expression of the cyclin-dependent kinase inhibitor p21. Furthermore, whereas AS160 overexpression resulted in p21 downregulation and rescued the arrested cell cycle in AS160-depeleted cells, p21 silencing rescued the inhibited cell cycle and proliferation in the cells. Thus, our results demonstrated that AS160 regulates glucose-independent eukaryotic cell proliferation through p21-dependent control of the cell cycle, and thereby revealed a molecular mechanism of AS160 modulation of cell cycle and proliferation that is of general physiological significance.

[Development of antibody medicines by bio-venture: lesson from license negotiations with mega pharmacies].

PubMed

Takada, Kenzo

2013-01-01

The current method of antibody production is mainly the hybridoma method, in which mice are immunized with an excess amount of antigen for a short period to promote activation and proliferation of B-lymphocytes producing the antibodies of interest. Because of the excess antigen, those producing low-affinity antibodies are activated. In contrast, human blood B-lymphocytes are activated through natural immune reactions, such as the reaction to infection. B-lymphocytes are stimulated repeatedly with a small amount of antigen, and thus only those producing high-affinity antibodies are activated. Consequently, the lymphocytes producing the high-affinity antibodies are accumulated in human blood. Therefore, human lymphocytes are an excellent source of high-affinity antibodies. Evec, Inc. has established a unique method to produce high-affinity antibodies from human lymphocytes using Epstein-Barr virus (EBV), which induces the proliferation of B-lymphocytes. The method first induces the proliferation of B-lymphocytes from human blood using EBV, and then isolates those producing the antibodies of interest. The key features of the Evec technique are: 1) development of a lymphocyte library consisting of 150 donors' lymphocytes from which donors suited to develop the antibodies of interest can be selected in 4 days; and 2) development of a sorting method and cell microarray method for selecting lymphocyte clones producing the target antibodies. Licensing agreements have been concluded with European and Japanese pharmaceutical companies for two types of antibody. This paper describes Evec's antibody technology and experience in license negotiations with Mega Pharmacies.

Different sensitivity of germinal center B cell-like diffuse large B cell lymphoma cells towards ibrutinib treatment

PubMed Central

2014-01-01

Background Although rituximab in the combination of CHOP chemotherapy has been widely used as the standard treatment for several kinds of B-cell non-Hodgkin lymphoma (B-NHL), a great number of B-NHL patients treated with this immunotherapy still develop primary and secondary resistance. Recently Bruton’s tyrosine kinase (Btk) inhibitor ibrutinib showed promising therapeutic effect in relapsed/refractory CLL and B-cell NHL, which provided essential alternatives for these patients. Methods The proliferation and apoptosis induction of tumor cells were measured by cell viability assay and Annexin-V staining. Western Blotting analysis and real-time PCR were used to detect the expression level of target proteins and chemokines production. Results We demonstrated that ibrutinib inhibited the proliferation and induced apoptosis of GCB-DLBCL cell lines through suppression of BCR signaling pathway and activation of caspase-3. Furthermore, the chemokines CCL3 and CCL4 production from tumor cells were also found to be attenuated by ibrutinib treatment. But different cell lines exhibited distinct sensitivity after ibrutinib treatment. Interestingly, the decreasing level of p-ERK after ibrutinib treatment, but not the basal expression level of Btk, correlated with different drug sensitivity. Conclusions Ibrutinib could be a potentially useful therapy for GCB-DLBCL and the decreasing level of p-ERK could become a useful biomarker to predict related therapeutic response. PMID:24693884

Placenta Derived Mesenchymal Stem Cells Hosted on RKKP Glass-Ceramic: A Tissue Engineering Strategy for Bone Regenerative Medicine Applications

PubMed Central

Fosca, Marco; De Bonis, Angela; Curcio, Mariangela; Lolli, Maria Grazia; De Stefanis, Adriana; Marchese, Rodolfo; Rau, Julietta V.

2016-01-01

In tissue engineering protocols, the survival of transplanted stem cells is a limiting factor that could be overcome using a cell delivery matrix able to support cell proliferation and differentiation. With this aim, we studied the cell-friendly and biocompatible behavior of RKKP glass-ceramic coated Titanium (Ti) surface seeded with human amniotic mesenchymal stromal cells (hAMSCs) from placenta. The sol-gel synthesis procedure was used to prepare the RKKP glass-ceramic material, which was then deposited onto the Ti surface by Pulsed Laser Deposition method. The cell metabolic activity and proliferation rate, the cytoskeletal actin organization, and the cell cycle phase distribution in hAMSCs seeded on the RKKP coated Ti surface revealed no significant differences when compared to the cells grown on the treated plastic Petri dish. The health of of hAMSCs was also analysed studying the mRNA expressions of MSC key genes and the osteogenic commitment capability using qRT-PCR analysis which resulted in being unchanged in both substrates. In this study, the combination of the hAMSCs' properties together with the bioactive characteristics of RKKP glass-ceramics was investigated and the results obtained indicate its possible use as a new and interesting cell delivery system for bone tissue engineering and regenerative medicine applications. PMID:28078286

1-O-hexadecyloxypropyl cidofovir (CMX001) effectively inhibits polyomavirus BK replication in primary human renal tubular epithelial cells.

PubMed

Rinaldo, Christine Hanssen; Gosert, Rainer; Bernhoff, Eva; Finstad, Solrun; Hirsch, Hans H

2010-11-01

Antiviral drugs for treating polyomavirus BK (BKV) replication in polyomavirus-associated nephropathy or hemorrhagic cystitis are of considerable clinical interest. Unlike cidofovir, the lipid conjugate 1-O-hexadecyloxypropyl cidofovir (CMX001) is orally available and has not caused detectable nephrotoxicity in rodent models or human studies to date. Primary human renal proximal tubular epithelial cells were infected with BKV-Dunlop, and CMX001 was added 2 h postinfection (hpi). The intracellular and extracellular BKV DNA load was determined by quantitative PCR. Viral gene expression was examined by quantitative reverse transcription-PCR, Western blotting, and immunofluorescence microscopy. We also examined host cell viability, proliferation, metabolic activity, and DNA replication. The titration of CMX001 identified 0.31 μM as the 90% effective concentration (EC(90)) for reducing the extracellular BKV load at 72 hpi. BKV large T antigen mRNA and protein expression was unaffected at 24 hpi, but the intracellular BKV genome was reduced by 90% at 48 hpi. Late gene expression was reduced by 70 and 90% at 48 and 72 hpi, respectively. Comparisons of CMX001 and cidofovir EC(90)s from 24 to 96 hpi demonstrated that CMX001 had a more rapid and enduring effect on BKV DNA and infectious progeny at 96 hpi than cidofovir. CMX001 at 0.31 μM had little effect on overall cell metabolism but reduced bromodeoxyuridine incorporation and host cell proliferation by 20 to 30%, while BKV infection increased cell proliferation in both rapidly dividing and near-confluent cultures. We conclude that CMX001 inhibits BKV replication with a longer-lasting effect than cidofovir at 400× lower levels, with fewer side effects on relevant host cells in vitro.

Therapeutic potential of target of rapamycin inhibitors.

PubMed

Easton, John B; Houghton, Peter J

2004-12-01

Target of rapamycin (TOR) functions within the cell as a transducer of information from various sources, including growth factors, energy sensors, and hypoxia sensors, as well as components of the cell regulating growth and division. Blocking TOR function mimics amino acid, and to some extent, growth factor deprivation and has a cytostatic effect on proliferating cells in vivo. Inhibition of TOR in vivo, utilising its namesake rapamycin, leads to immunosuppression. This property has been exploited successfully with the use of rapamycin and its derivatives as a therapeutic agent in the prevention of organ rejection after transplantation with relatively mild side effects when compared to other immunosuppressive agents. The cytostatic effect of TOR on vascular smooth muscle cell proliferation has also recently been exploited in the therapeutic application of rapamycin to drug eluting stents for angioplasty. These stents significantly reduce the amount of arterial reblockage that results from proliferating vascular smooth muscle cells. In cancer, the effect of blocking TOR function on tumour growth and disease progression is currently of major interest and is the basis for a number of ongoing clinical trials. However, different cell types and tumours respond differently to TOR inhibition, and TOR is clearly not cytostatic for all types of cancer cells in vitro or in vivo. As the molecular details of how TOR functions and the targets of TOR activity are further elucidated, tumour and tissue specific functions are being identified that implicate TOR in angiogenesis, apoptosis, and the reversal of some forms of cellular transformation. This review will describe our current understanding of TOR function, describe the current strategies for employing TOR inhibitors in clinical and preclinical development, and outline future strategies for appropriate targets of TOR inhibitors in the treatment of disease.

Alpha-CaMKII plays a critical role in determining the aggressive behavior of human osteosarcoma

PubMed Central

Daft, Paul G.; Yuan, Kaiyu; Warram, Jason M.; Klein, Michael J.; Siegal, Gene P.; Zayzafoon, Majd

2013-01-01

Osteosarcoma is among the most frequently occurring primary bone tumors, primarily affecting adolescents and young adults. Despite improvements in osteosarcoma treatment, more specific molecular targets are needed as potential therapeutic options. One target of interest is alpha-Ca2+/calmodulin-dependent protein kinase II (α-CaMKII), a ubiquitous mediator of Ca2+-linked signaling, which has been shown to regulate tumor cell proliferation and differentiation. Here, we investigate the role of α-CaMKII in the growth and tumorigenicity of human osteosarcoma. We show that α-CaMKII is highly expressed in primary osteosarcoma tissue derived from 114 patients and is expressed in varying levels in different human osteosarcoma cell lines (HOS, MG-63, MNNG/HOS and 143B). To examine whether α-CaMKII regulates osteosarcoma tumorigenic properties, we genetically inhibited α-CaMKII in two osteosarcoma cell lines using two different α-CaMKII shRNAs delivered by lentiviral vectors and overexpressed α-CaMKII by retrovirus. The genetic deletion of α-CaMKII by shRNA in MG-63 and 143B cells resulted in decreased proliferation (50 and 41%), migration (22 and 25%) and invasion (95 and 90%), respectively. The overexpression of α-CaMKII in HOS cells resulted in increased proliferation (240%), migration (640%) and invasion (10,000%). Furthermore, α-CaMKII deletion in MG-63 cells significantly reduced tumor burden in vivo (65%), while α-CaMKII overexpression resulted in tumor formation in a previously non-tumor forming osteosarcoma cell line (HOS). Our results suggest that α-CaMKII plays a critical role in determining the aggressive phenotype of osteosarcoma, and its inhibition could be an attractive therapeutic target to combat this devastating adolescent disease. PMID:23364534

Alpha-CaMKII plays a critical role in determining the aggressive behavior of human osteosarcoma.

PubMed

Daft, Paul G; Yuan, Kaiyu; Warram, Jason M; Klein, Michael J; Siegal, Gene P; Zayzafoon, Majd

2013-04-01

Osteosarcoma is among the most frequently occurring primary bone tumors, primarily affecting adolescents and young adults. Despite improvements in osteosarcoma treatment, more specific molecular targets are needed as potential therapeutic options. One target of interest is α-Ca(2+)/calmodulin-dependent protein kinase II (α-CaMKII), a ubiquitous mediator of Ca(2+)-linked signaling, which has been shown to regulate tumor cell proliferation and differentiation. Here, we investigate the role of α-CaMKII in the growth and tumorigenicity of human osteosarcoma. We show that α-CaMKII is highly expressed in primary osteosarcoma tissue derived from 114 patients, and is expressed in varying levels in different human osteosarcoma (OS) cell lines [MG-63, N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)/HOS, and 143B). To examine whether α-CaMKII regulates osteosarcoma tumorigenic properties, we genetically inhibited α-CaMKII in two osteosarcoma cell lines using two different α-CaMKII shRNAs delivered by lentiviral vectors and overexpressed α-CaMKII by retrovirus. The genetic deletion of α-CaMKII by short hairpin RNA (shRNA) in MG-63 and 143B cells resulted in decreased proliferation (50% and 41%), migration (22% and 25%), and invasion (95% and 90%), respectively. The overexpression of α-CaMKII in HOS cells resulted in increased proliferation (240%), migration (640%), and invasion (10,000%). Furthermore, α-CaMKII deletion in MG-63 cells significantly reduced tumor burden in vivo (65%), whereas α-CaMKII overexpression resulted in tumor formation in a previously nontumor forming osteosarcoma cell line (HOS). Our results suggest that α-CaMKII plays a critical role in determining the aggressive phenotype of osteosarcoma, and its inhibition could be an attractive therapeutic target to combat this devastating adolescent disease. ©2013 AACR.

Nuclear accumulation of SHIP1 mutants derived from AML patients leads to increased proliferation of leukemic cells.

PubMed

Nalaskowski, Marcus M; Ehm, Patrick; Rehbach, Christoph; Nelson, Nina; Täger, Maike; Modest, Kathrin; Jücker, Manfred

2018-05-28

The inositol 5-phosphatase SHIP1 acts as negative regulator of intracellular signaling in myeloid cells and is a tumor suppressor in myeloid leukemogenesis. After relocalization from the cytoplasm to the plasma membrane SHIP1 terminates PI3-kinase mediated signaling processes. Furthermore, SHIP1 is also found in distinct puncta in the cell nucleus and nuclear SHIP1 has a pro-proliferative function. Here we report the identification of five nuclear export signals (NESs) which regulate together with the two known nuclear localization signals (NLSs) the nucleocytoplasmic shuttling of SHIP1. Mutation of NLSs reduced the nuclear import and mutation of NESs decreased the nuclear export of SHIP1 in the acute myeloid leukemia (AML) cell line UKE-1. Interestingly, four SHIP1 mutants (K210R, N508D, V684E, Q1153L) derived from AML patients showed a nuclear accumulation after expression in UKE-1 cells. In addition, overexpression of the AML patient-derived mutation N508D caused an increased proliferation rate of UKE-1 cells in comparison to wild type SHIP1. Furthermore, we identified serine and tyrosine phosphorylation as a molecular mechanism for the regulation of nucleocytoplasmic shuttling of SHIP1 where tyrosine phosphorylation of distinct residues i.e. Y864, Y914, Y1021 reduces nuclear localization, whereas serine phosphorylation at S933 enhances nuclear localization of SHIP1. In summary, our data further implicate nuclear SHIP1 in cellular signaling and suggest that enhanced accumulation of SHIP1 mutants in the nucleus may be a contributory factor of abnormally high proliferation of AML cells. Copyright © 2018 Elsevier Inc. All rights reserved.

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

Co-culture with Sertoli cells promotes proliferation and migration of umbilical cord mesenchymal stem cells

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

Zhang, Fenxi, E-mail: fxzhang0824@gmail.com; Hong, Yan; Liang, Wenmei

Highlights: Black-Right-Pointing-Pointer Co-culture of Sertoli cells (SCs) with human umbilical cord mesenchymal stem cells (UCMSCs). Black-Right-Pointing-Pointer Presence of SCs dramatically increased proliferation and migration of UCMSCs. Black-Right-Pointing-Pointer Presence of SCs stimulated expression of Mdm2, Akt, CDC2, Cyclin D, CXCR4, MAPKs. -- Abstract: Human umbilical cord mesenchymal stem cells (hUCMSCs) have been recently used in transplant therapy. The proliferation and migration of MSCs are the determinants of the efficiency of MSC transplant therapy. Sertoli cells are a kind of 'nurse' cells that support the development of sperm cells. Recent studies show that Sertoli cells promote proliferation of endothelial cells and neuralmore » stem cells in co-culture. We hypothesized that co-culture of UCMSCs with Sertoli cells may also promote proliferation and migration of UCMSCs. To examine this hypothesis, we isolated UCMSCs from human cords and Sertoli cells from mouse testes, and co-cultured them using a Transwell system. We found that UCMSCs exhibited strong proliferation ability and potential to differentiate to other cell lineages such as osteocytes and adipocytes. The presence of Sertoli cells in co-culture significantly enhanced the proliferation and migration potential of UCMSCs (P < 0.01). Moreover, these phenotypic changes were accompanied with upregulation of multiple genes involved in cell proliferation and migration including phospho-Akt, Mdm2, phospho-CDC2, Cyclin D1, Cyclin D3 as well as CXCR4, phospho-p44 MAPK and phospho-p38 MAPK. These findings indicate that Sertoli cells boost UCMSC proliferation and migration potential.« less

Oxytocin stimulates cell proliferation in vaginal cell line Vk2E6E7.

PubMed

Kallak, Theodora K; Uvnäs-Moberg, Kerstin

2017-03-01

Objective During and after menopause, the symptoms of vaginal atrophy cause great discomfort and necessitate effective treatment options. Currently, vaginally applied oxytocin is being investigated as a treatment for the symptoms of vaginal atrophy in postmenopausal women. To clarify the mechanisms behind oxytocins effects on vaginal atrophy, the present study investigated the effects of oxytocin on cell proliferation in the cells of the Vk2E6E7 line, a non-tumour vaginal cell line. The study also compared the effects of oxytocin with those of estradiol (E2). Study design The effects of both oxytocin and E2 on the proliferation of Vk2E6E7 cells were investigated using Cell Proliferation ELISA BrdU Colorimetric Assay. The expression of both oxytocin and oxytocin receptor was studied in Vk2E6E7 cells using quantitative real-time polymerase chain reaction and immunofluorescent staining. Main outcome measures Cell proliferation and gene expression. Results Oxytocin increased cell proliferation both time dependently and dose dependently. This differed from the effect pattern observed in cells treated with E2. In addition, in oxytocin-treated cells, the oxytocin receptor was found to be co-localized with caveolin-1, indicating pro-proliferative signalling within the cell. Conclusions Oxytocin stimulates cell proliferation and the co-localization of oxytocin receptor with caveolin-1 in oxytocin-treated cells, supporting the role of oxytocin signalling in cell proliferation. In addition, these findings suggest that increased cell proliferation is one mechanism by which local vaginal oxytocin treatment increases vaginal thickness and relieves vaginal symptoms in postmenopausal women with vaginal atrophy.

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

Guo, Wenjing; Hao, Baixia; Wang, Qian

Extracellular signal-regulated kinases (ERKs) have been implicated to be dispensable for self-renewal of mouse embryonic stem (ES) cells, and simultaneous inhibition of both ERK signaling and glycogen synthase kinase 3 (GSK3) not only allows mouse ES cells to self-renew independent of extracellular stimuli but also enables more efficient derivation of naïve ES cells from mouse and rat strains. Interestingly, some ERKs stay active in mouse ES cells which are maintained in regular medium containing leukemia inhibitory factor (LIF) and bone morphogenetic protein (BMP). Yet, the upstream signaling for ERK activation and their roles in mouse ES cells, other than promotingmore » or priming differentiation, have not been determined. Here we found that mouse ES cells express three forms of Raf kinases, A-Raf, B-Raf, and C-Raf. Knocking-down each single Raf member failed to affect the sustained ERK activity, neither did A-Raf and B-Raf double knockdown or B-Raf and C-Raf double knockdown change it in ES cells. Interestingly, B-Raf and C-Raf double knockdown, not A-Raf and B-Raf knockdown, inhibited the maximal ERK activation induced by LIF, concomitant with the slower growth of ES cells. On the other hand, A-Raf, B-Raf, and C-Raf triple knockdown markedly inhibited both the maximal and sustained ERK activity in ES cells. Moreover, Raf triple knockdown, similar to the treatment of U-0126, an MEK inhibitor, significantly inhibited the survival and proliferation of ES cells, thereby compromising the colony propagation of mouse ES cells. In summary, our data demonstrate that all three Raf members are required for ERK activation in mouse ES cells and are involved in growth and survival of mouse ES cells. - Highlights: ●Mouse ES (mES) cells express all three Raf members, A-Raf, B-Raf, and C-Raf. ●Leukemia inhibitory factor (LIF) temporally activates ERKs in mES cells. ●B-Raf and C-Raf are required for LIF-induced maximal ERKs activity in mES cells. ●All Raf members are required for LIF-induced sustained ERK activity in mES cells. ●All Raf members are required the survival and proliferation of mES cells.« less

The usefulness of c-Kit in the immunohistochemical assessment of melanocytic lesions

PubMed Central

Pilloni, L.; Bianco, P.; Difelice, E.; Cabras, S.; Castellanos, M.E.; Atzori, L.; Ferreli, C.; Mulas, P.; Nemolato, S.; Faa, G.

2011-01-01

C-Kit (CD117), the receptor for the stem cell factor, a growth factor for melanocyte migration and proliferation, has shown differential immunostaining in various benign and malignant melanocytic lesions. The purpose of this study is to compare c-Kit immunostaining in benign nevi and in primary and metastatic malignant melanomas, to determine whether c-Kit can aid in the differential diagnosis of these lesions. c-Kit immunostaining was performed in 60 cases of pigmented lesions, including 39 benign nevi (5 blue nevi, 5 intra-dermal nevi, 3 junctional nevi, 15 cases of primary compound nevus, 11 cases of Spitz nevus), 18 cases of primary malignant melanoma and 3 cases of metastatic melanoma. The vast majority of nevi and melanomas examined in this study were positive for c-Kit, with minimal differences between benign and malignant lesions. C-Kit cytoplasmatic immunoreactivity in the intraepidermal proliferating nevus cells, was detected in benign pigmented lesions as well as in malignant melanoma, increasing with the age of patients (P=0.007) in both groups. The patient’s age at presentation appeared to be the variable able to cluster benign and malignant pigmented lesions. The percentage of c-Kit positive intraepidermal nevus cells was better associated with age despite other variables (P=0.014). The intensity and percentage of c-Kit positivity in the proliferating nevus cells in the dermis was significantly increased in malignant melanocytic lesions (P=0.015 and P=0.008) compared to benign lesions (compound melanocytic nevi, Spitz nevi, intradermal nevi, blue nevi). Immunostaning for c-Kit in metastatic melanomas was negative. Interestingly in two cases of melanoma occurring on a pre-existent nevus, the melanoma tumor cells showed strong cytoplasmatic and membranous positivity for c-kit, in contrast with the absence of any immunoreactivity in pre-existent intradermal nevus cells. C-Kit does not appear to be a strong immunohistochemical marker for distinguishing melanoma from melanocytic nevi, if we consider c-Kit expression in intraepidermal proliferating cells. The c-Kit expression in proliferating melanocytes in the dermis could help in the differential diagnosis between a superficial spreading melanoma (with dermis invasion) and a compound nevus or an intradermal nevus. Finally, c-Kit could be a good diagnostic tool for distinguishing benign compound nevi from malignant melanocytic lesions with dermis invasion and to differentiate metastatic melanoma from primary melanoma. PMID:22193299

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

Han, Seong-Su, E-mail: seong-su-han@uiowa.edu; Han, Sangwoo; Kamberos, Natalie L.

Highlights: • PL inhibits the proliferation of B-ALL cell lines irrespective of GC-resistance. • PL selectively kills B-ALL cells by increasing ROS, but not normal counterpart. • PL does not sensitize majority of B-ALL cells to DEX. • PL represses the network of constitutively activated TFs and modulates their target genes. • PL may serve as a new therapeutic molecule for GC-resistant B-ALL. - Abstract: Piperlongumine (PL), a pepper plant alkaloid from Piper longum, has anti-inflammatory and anti-cancer properties. PL selectively kills both solid and hematologic cancer cells, but not normal counterparts. Here we evaluated the effect of PL onmore » the proliferation and survival of B-cell acute lymphoblastic leukemia (B-ALL), including glucocorticoid (GC)-resistant B-ALL. Regardless of GC-resistance, PL inhibited the proliferation of all B-ALL cell lines, but not normal B cells, in a dose- and time-dependent manner and induced apoptosis via elevation of ROS. Interestingly, PL did not sensitize most of B-ALL cell lines to dexamethasone (DEX). Only UoC-B1 exhibited a weak synergistic effect between PL and DEX. All B-ALL cell lines tested exhibited constitutive activation of multiple transcription factors (TFs), including AP-1, MYC, NF-κB, SP1, STAT1, STAT3, STAT6 and YY1. Treatment of the B-ALL cells with PL significantly downregulated these TFs and modulated their target genes. While activation of AURKB, BIRC5, E2F1, and MYB mRNA levels were significantly downregulated by PL, but SOX4 and XBP levels were increased by PL. Intriguingly, PL also increased the expression of p21 in B-ALL cells through a p53-independent mechanism. Given that these TFs and their target genes play critical roles in a variety of hematological malignancies, our findings provide a strong preclinical rationale for considering PL as a new therapeutic agent for the treatment of B-cell malignancies, including B-ALL and GC-resistant B-ALL.« less

Supporting Aspartate Biosynthesis Is an Essential Function of Respiration in Proliferating Cells.

PubMed

Sullivan, Lucas B; Gui, Dan Y; Hosios, Aaron M; Bush, Lauren N; Freinkman, Elizaveta; Vander Heiden, Matthew G

2015-07-30

Mitochondrial respiration is important for cell proliferation; however, the specific metabolic requirements fulfilled by respiration to support proliferation have not been defined. Here, we show that a major role of respiration in proliferating cells is to provide electron acceptors for aspartate synthesis. This finding is consistent with the observation that cells lacking a functional respiratory chain are auxotrophic for pyruvate, which serves as an exogenous electron acceptor. Further, the pyruvate requirement can be fulfilled with an alternative electron acceptor, alpha-ketobutyrate, which provides cells neither carbon nor ATP. Alpha-ketobutyrate restores proliferation when respiration is inhibited, suggesting that an alternative electron acceptor can substitute for respiration to support proliferation. We find that electron acceptors are limiting for producing aspartate, and supplying aspartate enables proliferation of respiration deficient cells in the absence of exogenous electron acceptors. Together, these data argue a major function of respiration in proliferating cells is to support aspartate synthesis. Copyright © 2015 Elsevier Inc. All rights reserved.

Advanced glycation end products increase carbohydrate responsive element binding protein expression and promote cancer cell proliferation.

PubMed

Chen, Hanbei; Wu, Lifang; Li, Yakui; Meng, Jian; Lin, Ning; Yang, Dianqiang; Zhu, Yemin; Li, Xiaoyong; Li, Minle; Xu, Ye; Wu, Yuchen; Tong, Xuemei; Su, Qing

2014-09-01

Diabetic patients have increased levels of advanced glycation end products (AGEs) and the role of AGEs in regulating cancer cell proliferation is unclear. Here, we found that treating colorectal and liver cancer cells with AGEs promoted cell proliferation. AGEs stimulated both the expression and activation of a key transcription factor called carbohydrate responsive element binding protein (ChREBP) which had been shown to promote glycolytic and anabolic activity as well as proliferation of colorectal and liver cancer cells. Using siRNAs or the antagonistic antibody for the receptor for advanced glycation end-products (RAGE) blocked AGEs-induced ChREBP expression or cell proliferation in cancer cells. Suppressing ChREBP expression severely impaired AGEs-induced cancer cell proliferation. Taken together, these results demonstrate that AGEs-RAGE signaling enhances cancer cell proliferation in which AGEs-mediated ChREBP induction plays an important role. These findings may provide new explanation for increased cancer progression in diabetic patients. Copyright © 2014. Published by Elsevier Ireland Ltd.

Accelerated proliferation of hepatocytes in rats with iron overload after partial hepatectomy.

PubMed

An, Shucai; Soe, Kyaw; Akamatsu, Maki; Hishikawa, Yoshitaka; Koji, Takehiko

2012-11-01

Although iron overload is implicated in hepatocarcinogenesis, the precise mechanism was not known yet. In the present study, we investigated the effect of iron overload upon the induction of hepatocyte proliferation after 70% partial hepatectomy (PH) in rats fed with rat chow with 3% carbonyl iron for 3 months. In normal-diet rats, the increase in Ki-67 labeling index (LI) commenced at 24 h post-PH and the LIs of proliferating cell nuclear antigen (PCNA) incorporated 5-bromo-2'-deoxyuridine (BrdU) and phospho-histone H3 reached maximum values at 36 and 48 h after PH, respectively. In iron-overload rats, the above parameters occurred 12 h earlier compared to that of normal-diet rats, shortening the G0-G1 transition. Interestingly, nuclear staining for metallothionein (MT), which is essential for hepatocyte proliferation, was noted even at 0 h in iron-overload rats, while MT expression occurred at 6 h in the normal rats. Moreover, nuclear factor kappa B (NF-κB) expression, which is an essential early event leading to liver regeneration, was detected in Kupffer cells at 0 h in iron-overload rats. These results may indicate that overloaded iron, maybe through the induction of MT and NF-κB, may keep liver as a state ready to regenerate in response to PH, by bypassing signal transduction cascades involved in the initiation of liver regeneration.

Leaf shape: genetic controls and environmental factors.

PubMed

Tsukaya, Hirokazu

2005-01-01

In recent years, many genes have been identified that are involved in the developmental processes of leaf morphogenesis. Here, I review the mechanisms of leaf shape control in a model plant, Arabidopsis thaliana, focusing on genes that fulfill special roles in leaf development. The lateral, two-dimensional expansion of leaf blades is highly dependent on the determination of the dorsoventrality of the primordia, a defining characteristic of leaves. Having a determinate fate is also a characteristic feature of leaves and is controlled by many factors. Lateral expansion is not only controlled by general regulators of cell cycling, but also by the multi-level regulation of meristematic activities, e.g., specific control of cell proliferation in the leaf-length direction, in leaf margins and in parenchymatous cells. In collaboration with the polarized control of leaf cell elongation, these redundant and specialized regulating systems for cell cycling in leaf lamina may realize the elegantly smooth, flat structure of leaves. The unified, flat shape of leaves is also dependent on the fine integration of cell proliferation and cell enlargement. Interestingly, while a decrease in the number of cells in leaf primordia can trigger a cell volume increase, an increase in the number of cells does not trigger a cell volume decrease. This phenomenon is termed compensation and suggests the existence of some systems for integration between cell cycling and cell enlargement in leaf primordia via cell-cell communication. The environmental adjustment of leaf expansion to light conditions and gravity is also summarized.

Inducible Conditional Vascular-Specific Overexpression of Peroxisome Proliferator-Activated Receptor Beta/Delta Leads to Rapid Cardiac Hypertrophy

PubMed Central

Wagner, Kay-Dietrich; Vukolic, Ana; Baudouy, Delphine; Michiels, Jean-François

2016-01-01

Peroxisome proliferator-activated receptors are nuclear receptors which function as ligand-activated transcription factors. Among them, peroxisome proliferator-activated receptor beta/delta (PPARβ/δ) is highly expressed in the heart and thought to have cardioprotective functions due to its beneficial effects in metabolic syndrome. As we already showed that PPARβ/δ activation resulted in an enhanced cardiac angiogenesis and growth without impairment of heart function, we were interested to determine the effects of a specific activation of PPARβ/δ in the vasculature on cardiac performance under normal and in chronic ischemic heart disease conditions. We analyzed the effects of a specific PPARβ/δ overexpression in endothelial cells on the heart using an inducible conditional vascular-specific mouse model. We demonstrate that vessel-specific overexpression of PPARβ/δ induces rapid cardiac angiogenesis and growth with an increase in cardiomyocyte size. Upon myocardial infarction, vascular overexpression of PPARβ/δ, despite the enhanced cardiac vessel formation, does not protect against chronic ischemic injury. Our results suggest that the proper balance of PPARβ/δ activation in the different cardiac cell types is required to obtain beneficial effects on the outcome in chronic ischemic heart disease. PMID:27057154

Neogenin, a regulator of adult hippocampal neurogenesis, prevents depressive-like behavior.

PubMed

Sun, Dong; Sun, Xiang-Dong; Zhao, Lu; Lee, Dae-Hoon; Hu, Jin-Xia; Tang, Fu-Lei; Pan, Jin-Xiu; Mei, Lin; Zhu, Xiao-Juan; Xiong, Wen-Cheng

2018-01-08

Adult neurogenesis in hippocampal dentate gyrus (DG) is a complex, but precisely controlled process. Dysregulation of this event contributes to multiple neurological disorders, including major depression. Thus, it is of considerable interest to investigate how adult hippocampal neurogenesis is regulated. Here, we present evidence for neogenin, a multifunctional transmembrane receptor, to regulate adult mouse hippocampal neurogenesis. Loss of neogenin in adult neural stem cells (NSCs) or neural progenitor cells (NPCs) impaired NSCs/NPCs proliferation and neurogenesis, whereas increased their astrocytic differentiation. Mechanistic studies revealed a role for neogenin to positively regulate Gli1, a crucial downstream transcriptional factor of sonic hedgehog, and expression of Gli1 into neogenin depleted NSCs/NPCs restores their proliferation. Further morphological and functional studies showed additional abnormities, including reduced dendritic branches and spines, and impaired glutamatergic neuro-transmission, in neogenin-depleted new-born DG neurons; and mice with depletion of neogenin in NSCs/NPCs exhibited depressive-like behavior. These results thus demonstrate unrecognized functions of neogenin in adult hippocampal NSCs/NPCs-promoting NSCs/NPCs proliferation and neurogenesis and preventing astrogliogenesis and depressive-like behavior, and suggest neogenin regulation of Gli1 signaling as a possible underlying mechanism.

Organic Cation Transporter-Mediated Ergothioneine Uptake in Mouse Neural Progenitor Cells Suppresses Proliferation and Promotes Differentiation into Neurons

PubMed Central

Ishimoto, Takahiro; Nakamichi, Noritaka; Hosotani, Hiroshi; Masuo, Yusuke; Sugiura, Tomoko; Kato, Yukio

2014-01-01

The aim of the present study is to clarify the functional expression and physiological role in neural progenitor cells (NPCs) of carnitine/organic cation transporter OCTN1/SLC22A4, which accepts the naturally occurring food-derived antioxidant ergothioneine (ERGO) as a substrate in vivo. Real-time PCR analysis revealed that mRNA expression of OCTN1 was much higher than that of other organic cation transporters in mouse cultured cortical NPCs. Immunocytochemical analysis showed colocalization of OCTN1 with the NPC marker nestin in cultured NPCs and mouse embryonic carcinoma P19 cells differentiated into neural progenitor-like cells (P19-NPCs). These cells exhibited time-dependent [3H]ERGO uptake. These results demonstrate that OCTN1 is functionally expressed in murine NPCs. Cultured NPCs and P19-NPCs formed neurospheres from clusters of proliferating cells in a culture time-dependent manner. Exposure of cultured NPCs to ERGO or other antioxidants (edaravone and ascorbic acid) led to a significant decrease in the area of neurospheres with concomitant elimination of intracellular reactive oxygen species. Transfection of P19-NPCs with small interfering RNA for OCTN1 markedly promoted formation of neurospheres with a concomitant decrease of [3H]ERGO uptake. On the other hand, exposure of cultured NPCs to ERGO markedly increased the number of cells immunoreactive for the neuronal marker βIII-tubulin, but decreased the number immunoreactive for the astroglial marker glial fibrillary acidic protein (GFAP), with concomitant up-regulation of neuronal differentiation activator gene Math1. Interestingly, edaravone and ascorbic acid did not affect such differentiation of NPCs, in contrast to the case of proliferation. Knockdown of OCTN1 increased the number of cells immunoreactive for GFAP, but decreased the number immunoreactive for βIII-tubulin, with concomitant down-regulation of Math1 in P19-NPCs. Thus, OCTN1-mediated uptake of ERGO in NPCs inhibits cellular proliferation via regulation of oxidative stress, and also promotes cellular differentiation by modulating the expression of basic helix-loop-helix transcription factors via an unidentified mechanism different from antioxidant action. PMID:24586778

Effect of interleukins on the proliferation and survival of B cell chronic lymphocytic leukaemia cells.

PubMed Central

Mainou-Fowler, T; Copplestone, J A; Prentice, A G

1995-01-01

AIMS--To investigate the effects of interleukin (IL) 1, 2, 4, and 5 on the proliferation and survival of peripheral blood B cells from patients with B chronic lymphocytic leukaemia (B-CLL) and compare them with the effects on normal peripheral blood B cells. METHODS--The proliferation and survival of pokeweed mitogen (PWM) activated B cells from B-CLL (n = 12) and normal peripheral blood (n = 5) were studied in vitro in response to IL-1, IL-2 IL-4, and IL-5. Survival of cells in cultures with or without added interleukins was studied by microscopic examination of cells and DNA agarose gel electrophoresis. RESULTS--Proliferation was observed in both B-CLL and normal peripheral blood cells on culture with IL-2 alone and also in some, but not all, B-CLL and normal peripheral blood cells with IL-1 and IL-4. However, there was greater variability in B-CLL cell responses than in normal peripheral blood cells. Il-5 did not affect normal peripheral blood cell proliferation but it increased proliferation in two B-CLL cases. Synergistic effects of these cytokines were not detected. IL-4 inhibited normal peripheral blood and B-CLL cell proliferation after the addition of IL-2. Inhibition of B-CLL cell responses to IL-2 was also observed with IL-5 and Il-1. Survival of B-CLL cells in cultures was enhanced with IL-4 not by an increase in proliferation but by reduced apoptosis. No such effect was seen in normal peripheral blood cells. IL-2 had a less noticeable antiapoptotic effect; IL-5 enhanced apoptosis in B-CLL cells. CONCLUSIONS--B-CLL and normal peripheral blood cells proliferated equally well in response to IL-2. IL-4 had a much lower effect on B-CLL cell proliferation, but had noticeable antiapoptotic activity. IL-5 enhanced cell death by apoptosis. Images PMID:7629299

Ly49H Engagement Compensates for the Absence of Type I Interferon Signaling in Stimulating NK Cell Proliferation during MCMV Infection

PubMed Central

Geurs, Theresa L.; Zhao, Yun M.; Hill, Elaise B.; French, Anthony R.

2009-01-01

NK cells vigorously proliferate during viral infections, resulting in an expanded pool of innate lymphocytes that are able to participate in early host defense. The relative contributions of cytokines and activation receptors in stimulating NK cell proliferation during viral infections are not well characterized. In this study, we demonstrated that signaling through the NK cell activation receptor Ly49H was able to compensate for the absence of cytokine stimulation in the preferential phase of viral-induced proliferation during MCMV infection. In the absence of type I interferon stimulation, NK cell proliferation was strongly biased toward cells expressing the Ly49H receptor, even at early time points when minimal preferential Ly49H-mediated proliferation was observed in wild-type mice. In the absence of effective Ly49H signaling or following infection with virus that did not express the ligand for Ly49H, no difference was observed in the proliferation of subsets of NK cells that either express or lack expression of Ly49H, although the overall proliferation of NK cells in IFNαβR−/− mice was substantially reduced. These results highlight the contribution of NK cell activation receptors in stimulating proliferation and subsequent expansion of NK cells that are able to recognize virally infected cells. PMID:19828630

MicroRNA let-7b regulates neural stem cell proliferation and differentiation by targeting nuclear receptor TLX signaling

PubMed Central

Zhao, Chunnian; Sun, GuoQiang; Li, Shengxiu; Lang, Ming-Fei; Yang, Su; Li, Wendong; Shi, Yanhong

2010-01-01

Neural stem cell self-renewal and differentiation is orchestrated by precise control of gene expression involving nuclear receptor TLX. Let-7b, a member of the let-7 microRNA family, is expressed in mammalian brains and exhibits increased expression during neural differentiation. However, the role of let-7b in neural stem cell proliferation and differentiation remains unknown. Here we show that let-7b regulates neural stem cell proliferation and differentiation by targeting the stem cell regulator TLX and the cell cycle regulator cyclin D1. Overexpression of let-7b led to reduced neural stem cell proliferation and increased neural differentiation, whereas antisense knockdown of let-7b resulted in enhanced proliferation of neural stem cells. Moreover, in utero electroporation of let-7b to embryonic mouse brains led to reduced cell cycle progression in neural stem cells. Introducing an expression vector of Tlx or cyclin D1 that lacks the let-7b recognition site rescued let-7b-induced proliferation deficiency, suggesting that both TLX and cyclin D1 are important targets for let-7b-mediated regulation of neural stem cell proliferation. Let-7b, by targeting TLX and cyclin D1, establishes an efficient strategy to control neural stem cell proliferation and differentiation. PMID:20133835

MicroRNA let-7b regulates neural stem cell proliferation and differentiation by targeting nuclear receptor TLX signaling.

PubMed

Zhao, Chunnian; Sun, GuoQiang; Li, Shengxiu; Lang, Ming-Fei; Yang, Su; Li, Wendong; Shi, Yanhong

2010-02-02

Neural stem cell self-renewal and differentiation is orchestrated by precise control of gene expression involving nuclear receptor TLX. Let-7b, a member of the let-7 microRNA family, is expressed in mammalian brains and exhibits increased expression during neural differentiation. However, the role of let-7b in neural stem cell proliferation and differentiation remains unknown. Here we show that let-7b regulates neural stem cell proliferation and differentiation by targeting the stem cell regulator TLX and the cell cycle regulator cyclin D1. Overexpression of let-7b led to reduced neural stem cell proliferation and increased neural differentiation, whereas antisense knockdown of let-7b resulted in enhanced proliferation of neural stem cells. Moreover, in utero electroporation of let-7b to embryonic mouse brains led to reduced cell cycle progression in neural stem cells. Introducing an expression vector of Tlx or cyclin D1 that lacks the let-7b recognition site rescued let-7b-induced proliferation deficiency, suggesting that both TLX and cyclin D1 are important targets for let-7b-mediated regulation of neural stem cell proliferation. Let-7b, by targeting TLX and cyclin D1, establishes an efficient strategy to control neural stem cell proliferation and differentiation.

A novel estrogen receptor GPER mediates proliferation induced by 17β-estradiol and selective GPER agonist G-1 in estrogen receptor α (ERα)-negative ovarian cancer cells.

PubMed

Liu, Huidi; Yan, Yan; Wen, Haixia; Jiang, Xueli; Cao, Xuefeng; Zhang, Guangmei; Liu, Guoyi

2014-05-01

G protein-coupled estrogen receptor (GPER) is recently identified as a membrane-associated estrogen receptor that mediates non-genomic effects of estrogen. Our previous immunohistochemistry study found an association between GPER and the proliferation of epithelial ovarian cancer. However, the contributions and mechanisms of GPER in the proliferation of ovarian cancers are not clear. We have examined the role of GPER in estrogen receptor α (ERα)-negative/GPER positive OVCAR5 ovarian cancer cell line. MTT assay was used to detect cell proliferation. BrdU incorporation assay was used to measure the cells in S-phase. Protein expression of marker genes of proliferation, cell cycle and apoptosis were examined by Western blot. The results showed that 17β-estradiol and selective GPER agonist G-1 stimulated the proliferation of OVCAR5 cells and increased the cells in S-phase. Both ligands upregulated the protein levels of c-fos and cyclin D1. Small interfering RNA targeting GPER or G protein inhibitor pertussin toxin (PTX) inhibited basal cell proliferation and attenuated 17β-estradiol- or G-1-induced cell proliferation. GPER mediated cell growth was also associated with the apoptosis of OVCAR5 cells. These findings suggest that GPER has an important function in the proliferation of ovarian cancer cells lacking ERα. GPER might be a promising therapeutic target in ovarian cancer. © 2014 International Federation for Cell Biology.

The influence of dibutyryl adenosine cyclic monophosphate on cell proliferation in the epithelium of the jejunal crypts, the colonic crypts and in colonic carcinomata of rat.

PubMed

Tutton, P J; Barkla, D H

1980-01-01

1. Cell proliferation in the jejunal crypts, the colonic crypts and in dimethylhydrazine (DMH)-induced adenocarcinomata of rat colon was measured using a stathmokinetic technique. 2. Dibutryl cyclic adneosine monophosphate (dibutyryl cAMP) was found to inhibit cell proliferation in colonic crypts and in colonic adenocarcinomata. 3. Dibutryl cAMP at very high doses was found to inhibit jejunal crypt cell proliferation but at lower doses was found to accelerate jejunal crypt cell proliferation. 4. Neither bilateral adrenalectomy nor chemical sympathectomy was found to abolish the ability of dibutryl cAMP to stimulate jejunal crypt cell proliferation. 5. The present results are difficult to interpret in terms of known hormonal influences on cell proliferation in the tissues examined and of established actions, of these hormones on cyclic nucleotide metabolism in other tissues.

High Performance Liquid Chromatography-mass Spectrometry Analysis of High Antioxidant Australian Fruits with Antiproliferative Activity Against Cancer Cells.

PubMed

Sirdaarta, Joseph; Maen, Anton; Rayan, Paran; Matthews, Ben; Cock, Ian Edwin

2016-05-01

High antioxidant capacities have been linked to the treatment and prevention of several cancers. Recent reports have identified several native Australian fruits with high antioxidant capacities. Despite this, several of these species are yet to be tested for anticancer activity. Solvent extracts prepared from high antioxidant native Australian fruits were analyzed for antioxidant capacity by the di (phenyl)-(2,4,6-trinitrophenyl) iminoazanium free radical scavenging assay. Antiproliferative activities against CaCo2 and HeLa cancer cells were determined by a multicellular tumor spheroid-based cell proliferation assay. Toxicity was determined by Artemia franciscana bioassay. Methanolic extracts of all plant species displayed high antioxidant contents (equivalent to approximately 7-16 mg of vitamin C per gram of fruit extracted). Most aqueous extracts also contained relatively high antioxidant capacities. In contrast, the ethyl acetate, chloroform, and hexane extracts of most species (except lemon aspen and bush tomato) had lower antioxidant contents (below 1.5 mg of vitamin C equivalents per gram of plant material extracted). The antioxidant contents correlated with the ability of the extracts to inhibit proliferation of CaCo2 and HeLa cancer cell lines. The high antioxidant methanolic extracts of all species were potent inhibitors of cell proliferation. The methanolic lemon aspen extract was particularly effective, with IC50 values of 480 and 769 μg/mL against HeLa and CaCo2 cells, respectively. In contrast, the lower antioxidant ethyl acetate and hexane extracts (except the lemon aspen ethyl acetate extract) generally did not inhibit cancer cell proliferation or inhibited to only a minor degree. Indeed, most of the ethyl acetate and hexane extracts induced potent cell proliferation. The native tamarind ethyl acetate extract displayed low-moderate toxicity in the A. franciscana bioassay (LC50 values below 1000 μg/mL). All other extracts were nontoxic. A total of 145 unique mass signals were detected in the lemon aspen methanolic and aqueous extracts by nonbiased high-performance liquid chromatography-mass spectrometry analysis. Of these, 20 compounds were identified as being of particular interest due to their reported antioxidant and/or anticancer activities. The lack of toxicity and antiproliferative activity of the high antioxidant plant extracts against HeLa and CaCo2 cancer cell lines indicates their potential in the treatment and prevention of some cancers. Australian fruit extracts with high antioxidant contents were potent inhibitors of CaCo2 and HeLa carcinoma cell proliferationMethanolic lemon aspen extract was particularly potent, with IC50 values of 480 μg/mL (HeLa) and 769 μg/mL (CaCo2)High-performance liquid chromatography-mass spectrometry-quadrupole time-of-flight analysis highlighted and putatively identified 20 compounds in the antiproliferative lemon aspen extractsIn contrast, lower antioxidant content extracts stimulated carcinoma cell proliferationAll extracts with antiproliferative activity were nontoxic in the Artemia nauplii assay. Abbreviations used: DPPH: di (phenyl)- (2,4,6-trinitrophenyl) iminoazanium, HPLC: High-performance liquid chromatography, IC50: The concentration required to inhibit by 50%, LC50: The concentration required to achieve 50% mortality, MS: Mass spectrometry.

A Pitx2-MicroRNA Pathway Modulates Cell Proliferation in Myoblasts and Skeletal-Muscle Satellite Cells and Promotes Their Commitment to a Myogenic Cell Fate

PubMed Central

Lozano-Velasco, Estefanía; Vallejo, Daniel; Esteban, Francisco J.; Doherty, Chris; Hernández-Torres, Francisco; Franco, Diego

2015-01-01

The acquisition of a proliferating-cell status from a quiescent state as well as the shift between proliferation and differentiation are key developmental steps in skeletal-muscle stem cells (satellite cells) to provide proper muscle regeneration. However, how satellite cell proliferation is regulated is not fully understood. Here, we report that the c-isoform of the transcription factor Pitx2 increases cell proliferation in myoblasts by downregulating microRNA 15b (miR-15b), miR-23b, miR-106b, and miR-503. This Pitx2c-microRNA (miRNA) pathway also regulates cell proliferation in early-activated satellite cells, enhancing Myf5+ satellite cells and thereby promoting their commitment to a myogenic cell fate. This study reveals unknown functions of several miRNAs in myoblast and satellite cell behavior and thus may have future applications in regenerative medicine. PMID:26055324

Different characteristics of mesenchymal stem cells isolated from different layers of full term placenta

PubMed Central

Ha, Chul-Won; Kim, Jin A; Heo, Jin-Chul; Han, Woo-Jung; Oh, Soo-Young; Choi, Suk-Joo

2017-01-01

Background The placenta is a very attractive source of mesenchymal stem cells (MSCs) for regenerative medicine due to readily availability, non-invasive acquisition, and avoidance of ethical issues. Isolating MSCs from parts of placenta tissue has obtained growing interest because they are assumed to exhibit different proliferation and differentiation potentials due to complex structures and functions of the placenta. The objective of this study was to isolate MSCs from different parts of the placenta and compare their characteristics. Methods Placenta was divided into amniotic epithelium (AE), amniotic membrane (AM), chorionic membrane (CM), chorionic villi (CV), chorionic trophoblast without villi (CT-V), decidua (DC), and whole placenta (Pla). Cells isolated from each layer were subjected to analyses for their morphology, proliferation ability, surface markers, and multi-lineage differentiation potential. MSCs were isolated from all placental layers and their characteristics were compared. Findings Surface antigen phenotype, morphology, and differentiation characteristics of cells from all layers indicated that they exhibited properties of MSCs. MSCs from different placental layers had different proliferation rates and differentiation potentials. MSCs from CM, CT-V, CV, and DC had better population doubling time and multi-lineage differentiation potentials compared to those from other layers. Conclusions Our results indicate that MSCs with different characteristics can be isolated from all layers of term placenta. These finding suggest that it is necessary to appropriately select MSCs from different placental layers for successful and consistent outcomes in clinical applications. PMID:28225815

Anti-rheumatic drug iguratimod (T-614) alleviates cancer-induced bone destruction via down-regulating interleukin-6 production in a nuclear factor-κB-dependent manner.

PubMed

Sun, Yue; Ye, Da-Wei; Zhang, Peng; Wu, Ying-Xing; Wang, Bang-Yan; Peng, Guang; Yu, Shi-Ying

2016-10-01

Cytokines are believed to be involved in a "vicious circle" of progressive interactions in bone metastasis. Iguratimod is a novel anti-rheumatic drug which is reported to have the capability of anti-cytokines. In this study, a rat model was constructed to investigate the effect of iguratimod on bone metastasis and it was found that iguratimod alleviated cancer-induced bone destruction. To further explore whether an anti-tumor activity of iguratimod contributes to the effect of bone resorption suppression, two human breast cancer cell lines MDA-MB-231 and MCF-7 were studied. The effect of iguratimod on tumor proliferation was detected by CCK-8 assay and flow cytometry. The effects of iguratimod on migration and invasion of cancer cells were determined by wound-healing and Transwell assays. Results showed that high dose (30 μg/mL) iguratimod slightly suppressed the proliferation of cancer cells but failed to inhibit their migration and invasion capacity. Interestingly, iguratimod decreased the transcription level of IL-6 in MDA-MB-231 cells in a concentration-dependent manner. Moreover, iguratimod partially impaired NF-κB signaling by suppressing the phosphorylation of NF-κB p65 subunit. Our findings indicated that iguratimod may alleviate bone destruction by partially decreasing the expression of IL-6 in an NF-κB-dependent manner, while it has little effect on the tumor proliferation and invasion.

Estrogen effects of Daldinia concentrica and Psathyrella efflorescens extracts in vitro.

PubMed

Benie, Tanon; Kouakou, Koffi; Thieulant, Marie-Lise

2008-02-28

Daldinia concentrica and Psathyrella efflorescens are two fungi used in African traditional medicine. In the present study, their extracts were evaluated for their steroid activities in estrogen- or androgen-dependent cell lines using as endpoints steroid-dependent transcriptional activity and cell proliferation. Treatment of human breast cancer MCF-7 cells with 15 or 30 microg/ml of Daldinia concentrica or Psathyrellaefflorescens extracts in the absence of 17beta-estradiol (E2) significantly increased the transcriptional activity of an estrogen receptor (ER)-dependent reporter gene, in the same range as E2. Similar data were obtained in gonadotrope cell line alpha-T3-1. All the effects were prevented by the pure estrogen antagonist, ICI 182,780. In the absence of steroid addition, the two extracts induced cell proliferation of ER-dependent MCF-7 and Ishikawa Var-I cell lines by approximately 100% of the E2 response. Combination treatments with E2 showed no competitive or additive effects in the two latter cell lines. Interestingly, the extracts had no androgen-like response in androgen receptor (AR)-positive and ER-negative MDA-MB231 cells, suggesting that fungi effects are estrogen specific and extracts are not toxic at used concentrations. Results provided evidence that Daldinia concentrica or Psathyrellaefflorescens extracts induce estrogen-like effects in ER-positive cell lines, which could be responsible of the effects observed in vivo.

Silencing by nuclear matrix attachment distinguishes cell-type specificity: association with increased proliferation capacity

PubMed Central

Linnemann, Amelia K.; Krawetz, Stephen A.

2009-01-01

DNA loop organization by nuclear scaffold/matrix attachment is a key regulator of gene expression that may provide a means to modulate phenotype. We have previously shown that attachment of genes to the NaCl-isolated nuclear matrix correlates with their silencing in HeLa cells. In contrast, expressed genes were associated with the lithium 3,5-diiodosalicylate (LIS)-isolated nuclear scaffold. To define their role in determining phenotype matrix attached regions (MARs) on human chromosomes 14–18 were identified as a function of expression in a primary cell line. The locations of MARs in aortic adventitial fibroblast (AoAF) cells were very stable (r = 0.909) and 96% of genes attached at MARs are silent (P < 0.001). Approximately one-third of the genes uniquely expressed in AoAF cells were associated with the HeLa cell nuclear matrix and silenced. Comparatively, 81% were associated with the AoAF cell nuclear scaffold (P < 0.001) and expressed. This suggests that nuclear scaffold/matrix association mediates a portion of cell type-specific gene expression thereby modulating phenotype. Interestingly, nuclear matrix attachment and thus silencing of specific genes that regulate proliferation and maintain the integrity of the HeLa cell genome suggests that transformation may at least in part be achieved through aberrant nuclear matrix attachment. PMID:19276204

DD-RT-PCR identifies 7-dehydrocholesterol reductase as a key marker of early Leydig cell steroidogenesis.

PubMed

Anbalagan, M; Yashwanth, R; Jagannadha Rao, A

2004-04-30

Postnatal Leydig cell development in rat involves an initial phase of proliferation of progenitor Leydig cells (PLCs) and subsequent differentiation of these cells into immature Leydig cells (ILCs) and adult Leydig cells (ALCs). With an objective to identify the molecular changes associated with Leydig cell differentiation, the mRNA population in PLCs and ILCs were analyzed by the technique of differential display reverse transcription polymerase chain reaction (DD-RT-PCR). Results revealed differential expression of several transcripts in PLCs and ILCs. Of the several differentially expressed transcripts, the expression of transcripts corresponding to collagen IV alpha6 (Col IV alpha6) and ribosomal protein L 41 (RpL41) decreased during the differentiation of PLC to ILC. Also there was an increase in the expression of transcripts encoding enzymes such as microsomal glutathione-S-transferase (mGST 1) and 7-dehydrocholesterol reductase (7-DHCR) during this process. While Col IV alpha6 and RpL41 are known to be involved in cellular proliferation, mGST 1 and 7-DHCR are essential for normal Leydig cell steroidogenesis. A detailed study on 7-DHCR expression in Leydig cells revealed that this enzyme plays a crucial role in steroidogenesis. Interestingly expression of this enzyme is not under acute regulation by Luteinizing hormone (LH). Copyright 2004 Elsevier Ireland Ltd.

Cell proliferation and apoptosis during histogenesis of the guinea pig and rabbit cerebellar cortex.

PubMed

Lossi, Laura; Coli, Alessandra; Giannessi, Elisabetta; Stornelli, Maria Rita; Marroni, Paolo

2002-01-01

Cell proliferation and apoptosis are essential for development of the nervous system. In this study we have investigated the histogenesis of the cerebellar cortex in guinea pig (a precocial species) and rabbit (an altricial species) at different stages of pregnancy and postnatal life. Proliferating cells were identified after labeling with antibodies against the proliferating cell nuclear antigen (PCNA) and/or the Ki-67 antigen. Apoptotic cells were visualized in situ by the TUNEL method and by immunodetection of cleaved caspase 3 and 9. In guinea pigs, both proliferating and apoptotic cells were detected during pre-natal life (E0-E40). Conversely, cell proliferation and apoptosis in rabbits were temporally restricted to early postnatal weeks (P0-P20). In both species cell proliferation was mainly linked to differentiation and migration of the granule cells. In both species, the majority of cells undergoing programmed cell death likely corresponded to granule cells. They were mainly detected in the external granular layer, and were by far more common than previously reported in other locations of the postnatal brain. This study shows that apoptosis is a shared process of cell death during cerebellar development in both altricial and precocial animals, and that there is a direct spatial and temporal correlation between cell proliferation and death in two mammals with different time tables in cerebellar maturation.

The anti-oncogenic influence of ellagic acid on colon cancer cells in leptin-enriched microenvironment.

PubMed

Yousef, Amany I; El-Masry, Omar S; Yassin, Eman H

2016-10-01

Ellagic acid (EA) has been proposed as a promising candidate for therapeutic use in colon cancer. Investigation of the effectiveness of EA in a leptin-enriched model might have been given a little interest. Here in, we investigated the anti-tumor effect of EA in the presence of leptin to reflect on therapeutic use of EA in obesity-linked colon cancer. Proven effective in leptin-enriched microenvironment, EA inhibited cell proliferation of HCT-116 and CaCo-2 cell lines, modulated cell cycle, translocated Bax to the mitochondrial fraction of cells, activated caspase-8, and reduced PCNA expression. The current study findings cast a beam of light on the potential therapeutic use of EA in obesity-related colon carcinogenesis.

Music application alleviates short-term memory impairments through increasing cell proliferation in the hippocampus of valproic acid-induced autistic rat pups.

PubMed

Lee, Sung-Min; Kim, Bo-Kyun; Kim, Tae-Woon; Ji, Eun-Sang; Choi, Hyun-Hee

2016-06-01

Autism is a neurodevelopmental disorder and this disorder shows impairment in reciprocal social interactions, deficits in communication, and restrictive and repetitive patterns of behaviors and interests. The effect of music on short-term memory in the view of cell proliferation in the hippocampus was evaluated using valproic acid-induced autistic rat pups. Animal model of autism was made by subcutaneous injection of 400-mg/kg valproic acid into the rat pups on the postnatal day 14. The rat pups in the music-applied groups were exposed to the 65-dB comfortable classic music for 1 hr once a day, starting postnatal day 15 and continued until postnatal day 28. In the present results, short-term memory was deteriorated by autism induction. The numbers of 5-bromo-2'-deoxyridine (BrdU)-positive, Ki-67-positive, and doublecortin (DCX)-positive cells in the hippocampal dentate gyrus were decreased by autism induction. Brain-derived neurotrophic factor (BDNF) and tyrosine kinase B (TrkB) expressions in the hippocampus were also suppressed in the autistic rat pups. Music application alleviated short-term memory deficits with enhancing the numbers of BrdU-positive, Ki-67-positive, and DCX-positive cells in the autistic rat pups. Music application also enhanced BDNF and TrkB expressions in the autistic rat pups. The present study show that application of music enhanced hippocampal cell proliferation and alleviated short-term memory impairment through stimulating BDNF-TrkB signaling in the autistic rat pups. Music can be suggested as the therapeutic strategy to overcome the autism-induced memory deficits.

RB1 deficiency in triple-negative breast cancer induces mitochondrial protein translation.

PubMed

Jones, Robert A; Robinson, Tyler J; Liu, Jeff C; Shrestha, Mariusz; Voisin, Veronique; Ju, YoungJun; Chung, Philip E D; Pellecchia, Giovanna; Fell, Victoria L; Bae, SooIn; Muthuswamy, Lakshmi; Datti, Alessandro; Egan, Sean E; Jiang, Zhe; Leone, Gustavo; Bader, Gary D; Schimmer, Aaron; Zacksenhaus, Eldad

2016-10-03

Triple-negative breast cancer (TNBC) includes basal-like and claudin-low subtypes for which no specific treatment is currently available. Although the retinoblastoma tumor-suppressor gene (RB1) is frequently lost together with TP53 in TNBC, it is not directly targetable. There is thus great interest in identifying vulnerabilities downstream of RB1 that can be therapeutically exploited. Here, we determined that combined inactivation of murine Rb and p53 in diverse mammary epithelial cells induced claudin-low-like TNBC with Met, Birc2/3-Mmp13-Yap1, and Pvt1-Myc amplifications. Gene set enrichment analysis revealed that Rb/p53-deficient tumors showed elevated expression of the mitochondrial protein translation (MPT) gene pathway relative to tumors harboring p53 deletion alone. Accordingly, bioinformatic, functional, and biochemical analyses showed that RB1-E2F complexes bind to MPT gene promoters to regulate transcription and control MPT. Additionally, a screen of US Food and Drug Administration-approved (FDA-approved) drugs identified the MPT antagonist tigecycline (TIG) as a potent inhibitor of Rb/p53-deficient tumor cell proliferation. TIG preferentially suppressed RB1-deficient TNBC cell proliferation, targeted both the bulk and cancer stem cell fraction, and strongly attenuated xenograft growth. It also cooperated with sulfasalazine, an FDA-approved inhibitor of cystine xCT antiporter, in culture and xenograft assays. Our results suggest that RB1 deficiency promotes cancer cell proliferation in part by enhancing mitochondrial function and identify TIG as a clinically approved drug for RB1-deficient TNBC.

RB1 deficiency in triple-negative breast cancer induces mitochondrial protein translation

PubMed Central

Jones, Robert A.; Robinson, Tyler J.; Liu, Jeff C.; Shrestha, Mariusz; Voisin, Veronique; Ju, YoungJun; Chung, Philip E.D.; Pellecchia, Giovanna; Fell, Victoria L.; Bae, SooIn; Muthuswamy, Lakshmi; Egan, Sean E.; Jiang, Zhe; Leone, Gustavo; Bader, Gary D.; Schimmer, Aaron

2016-01-01

Triple-negative breast cancer (TNBC) includes basal-like and claudin-low subtypes for which no specific treatment is currently available. Although the retinoblastoma tumor-suppressor gene (RB1) is frequently lost together with TP53 in TNBC, it is not directly targetable. There is thus great interest in identifying vulnerabilities downstream of RB1 that can be therapeutically exploited. Here, we determined that combined inactivation of murine Rb and p53 in diverse mammary epithelial cells induced claudin-low–like TNBC with Met, Birc2/3-Mmp13-Yap1, and Pvt1-Myc amplifications. Gene set enrichment analysis revealed that Rb/p53-deficient tumors showed elevated expression of the mitochondrial protein translation (MPT) gene pathway relative to tumors harboring p53 deletion alone. Accordingly, bioinformatic, functional, and biochemical analyses showed that RB1-E2F complexes bind to MPT gene promoters to regulate transcription and control MPT. Additionally, a screen of US Food and Drug Administration–approved (FDA-approved) drugs identified the MPT antagonist tigecycline (TIG) as a potent inhibitor of Rb/p53-deficient tumor cell proliferation. TIG preferentially suppressed RB1-deficient TNBC cell proliferation, targeted both the bulk and cancer stem cell fraction, and strongly attenuated xenograft growth. It also cooperated with sulfasalazine, an FDA-approved inhibitor of cystine xCT antiporter, in culture and xenograft assays. Our results suggest that RB1 deficiency promotes cancer cell proliferation in part by enhancing mitochondrial function and identify TIG as a clinically approved drug for RB1-deficient TNBC. PMID:27571409

In silico characterization of cell-cell interactions using a cellular automata model of cell culture.

PubMed

Kihara, Takanori; Kashitani, Kosuke; Miyake, Jun

2017-07-14

Cell proliferation is a key characteristic of eukaryotic cells. During cell proliferation, cells interact with each other. In this study, we developed a cellular automata model to estimate cell-cell interactions using experimentally obtained images of cultured cells. We used four types of cells; HeLa cells, human osteosarcoma (HOS) cells, rat mesenchymal stem cells (MSCs), and rat smooth muscle A7r5 cells. These cells were cultured and stained daily. The obtained cell images were binarized and clipped into squares containing about 10 4 cells. These cells showed characteristic cell proliferation patterns. The growth curves of these cells were generated from the cell proliferation images and we determined the doubling time of these cells from the growth curves. We developed a simple cellular automata system with an easily accessible graphical user interface. This system has five variable parameters, namely, initial cell number, doubling time, motility, cell-cell adhesion, and cell-cell contact inhibition (of proliferation). Within these parameters, we obtained initial cell numbers and doubling times experimentally. We set the motility at a constant value because the effect of the parameter for our simulation was restricted. Therefore, we simulated cell proliferation behavior with cell-cell adhesion and cell-cell contact inhibition as variables. By comparing growth curves and proliferation cell images, we succeeded in determining the cell-cell interaction properties of each cell. Simulated HeLa and HOS cells exhibited low cell-cell adhesion and weak cell-cell contact inhibition. Simulated MSCs exhibited high cell-cell adhesion and positive cell-cell contact inhibition. Simulated A7r5 cells exhibited low cell-cell adhesion and strong cell-cell contact inhibition. These simulated results correlated with the experimental growth curves and proliferation images. Our simulation approach is an easy method for evaluating the cell-cell interaction properties of cells.

Tetraspanin CD9 modulates human lymphoma cellular proliferation via histone deacetylase activity

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

Herr, Michael J.; Department of Medicine, The University of Tennessee Health Science Center, Memphis, TN 38163; Department of Molecular Sciences, The University of Tennessee Health Science Center, Memphis, TN 38163

2014-05-16

Highlights: • CD9 is differentially expressed in human Burkitt’s lymphoma cells. • We found that CD9 expression promotes these cells proliferation. • CD9 expression also increases HDAC activity. • HDAC inhibition decreased both cell proliferation and importantly CD9 expression. • CD9 may dictate HDAC efficacy and play a role in HDAC regulation. - Abstract: Non-Hodgkin Lymphoma (NHL) is a type of hematological malignancy that affects two percent of the overall population in the United States. Tetraspanin CD9 is a cell surface protein that has been thoroughly demonstrated to be a molecular facilitator of cellular phenotype. CD9 expression varies in twomore » human lymphoma cell lines, Raji and BJAB. In this report, we investigated the functional relationship between CD9 and cell proliferation regulated by histone deacetylase (HDAC) activity in these two cell lines. Introduction of CD9 expression in Raji cells resulted in significantly increased cell proliferation and HDAC activity compared to Mock transfected Raji cells. The increase in CD9–Raji cell proliferation was significantly inhibited by HDAC inhibitor (HDACi) treatment. Pretreatment of BJAB cells with HDAC inhibitors resulted in a significant decrease in endogenous CD9 mRNA and cell surface expression. BJAB cells also displayed decreased cell proliferation after HDACi treatment. These results suggest a significant relationship between CD9 expression and cell proliferation in human lymphoma cells that may be modulated by HDAC activity.« less

Pro-Lipogenic Action of Lysophosphatidic Acid in Ovarian Cancer

DTIC Science & Technology

2013-07-01

One of the key mediators of fatty acid b-oxidation is carnitine pamitoyl transferase 1A (CPT1A), which is overexpressed in malignant ovarian...MAGL, inhibits growth of ovarian cancer cell lines. Most interestingly, inhibition of carnitine palmitoyl transferase 1 (CPT1), the rate-limiting...Manuscript in preparation: Shao H, Mukherjee A, Jing K, Yuan F, and Fang X. Carnitine palmitoyl transferase 1A mediates proliferation and survival of

The Regulatory Interactions of p21 and PCNA in Human Breast Cancer

DTIC Science & Technology

2002-07-01

Proliferating cell nuclear antigen (PCNA) is a multifunctional enzyme involved in multiple cellular processes including DNA replication and repair...During DNA replication , PCNA function as an accessory factor- for the DNA polymerases E arid and are part of a multiprotein DNA replication complex...a cyclin-dependent kinase inhibitor, p21WAF1 ability to inhibit DNA replication in response to DNA damage has been wall characterized. Interestingly

Long Non-Coding RNA HOTAIR Regulates the Proliferation, Self-Renewal Capacity, Tumor Formation and Migration of the Cancer Stem-Like Cell (CSC) Subpopulation Enriched from Breast Cancer Cells.

PubMed

Deng, Jia; Yang, Mengchang; Jiang, Rong; An, Ning; Wang, Xiaoshan; Liu, Bin

2017-01-01

Long non-coding RNAs (lncRNAs) play important roles in the malignant behavior of cancer. HOTAIR, a well-studied lncRNA, contributes to breast cancer development, and overexpression of HOTAIR predicts a poor prognosis. However, the regulatory role of HOTAIR in the cancer stem-like cell (CSC) subpopulation remains largely unknown. Our goal was to determine the regulatory functions of HOTAIR in the processes of self-renewal capacity, tumor formation and proliferation of CSCs derived from breast cancer. We first enriched and incubated the CSC population derived from breast cancer cell line MCF7 (CSC-MCF7) or MDA-MB-231 (MB231, CSC-MB231). Self-renewal capacity and tumor formation were assessed in vitro and in vivo to determine the stemness of CSCs. We assessed the impact on ectopically upregulated or downregulated expression of HOTAIR in CSCs by soft agar, self-renewal capacity and CCK-8 assays. The functional domain of HOTAIR was determined by truncation. RT-qPCR and semiquantitative Western blotting were performed to detect the expression levels of genes of interest. Chromatin IP (ChIP) was employed to detect the transcriptional regulatory activity of p53 on its target gene. After the identification of CSC properties, RT-qPCR analysis revealed that HOTAIR, but not other cancer-associated lncRNAs, is highly upregulated in both CSC-MCF7 and CSC-MB231 populations compared with MCF7 and MB231 populations. By modulating the level of HOTAIR expression, we showed that HOTAIR tightly regulates the proliferation, colony formation, migration and self-renewal capacity of CSCs. Moreover, full-length HOTAIR transcriptionally inhibits miR-34a specifically, leading to upregulation of Sox2, which is targeted by miR-34a. Ectopic introduction of miR-34a mimics reverses the effects of HOTAIR on the physiological processes of CSCs, indicating that HOTAIR affects these processes, including self-renewal capacity; these effects are dependent on the regulation of Sox2 via miR-34a. Interestingly, tight transcriptional regulation of p53 by HOTAIR was found; accordingly, p21 is indirectly regulated by HOTAIR, resulting in cell cycle entry. These results suggest that HOTAIR is a key regulator of proliferation, colony formation, invasion and self-renewal capacity in breast CSCs, which occurs in part through regulation of Sox2 and p53.

Elevated small GTPase activation influences the cell proliferation signaling control in Niemann-Pick type C fibroblasts.

PubMed

Corey, Deborah A; Kelley, Thomas J

2007-07-01

Niemann-Pick type C (NPC) disease is characterized at the cellular level by the intracellular accumulation of free cholesterol. We have previously identified a similar phenotype in cystic fibrosis (CF) cell models that results in the activation of the small GTPase RhoA. The hypothesis of this study was that NPC cells would also exhibit an increase in small GTPase activation. An examination of the active, GTP-bound form of GTPases revealed a basal increase in the content of the active-form Ras and RhoA small GTPases in NPC fibroblasts compared to wt controls. To assess whether this increase in GTP-bound Ras and RhoA manifests a functional outcome, the expression of the proliferation control proteins p21/waf1 and cyclin D were examined. Consistent with increased GTPase signaling, p21/waf1 expression is reduced and cyclin D expression is elevated in NPC fibroblasts. Interestingly, cell growth rate is not altered in NPC fibroblasts compared to wt cells. However, NPC sensitivity to statin treatment is reversed by addition of the isoprenoid geranylgeranyl pyrophosphate (GGPP), a modifier of RhoA. It is concluded that Ras and RhoA basal activation is elevated in NPC fibroblasts and has an impact on cell survival pathways.

Antitumor and Angiostatic Activities of the Antimicrobial Peptide Dermaseptin B2

PubMed Central

van Zoggel, Hanneke; Carpentier, Gilles; Dos Santos, Célia; Hamma-Kourbali, Yamina; Courty, José; Amiche, Mohamed; Delbé, Jean

2012-01-01

Recently, we have found that the skin secretions of the Amazonian tree frog Phyllomedusa bicolor contains molecules with antitumor and angiostatic activities and identified one of them as the antimicrobial peptide dermaseptin (Drs) B2. In the present study we further explored the in vitro and in vivo antitumor activity of this molecule and investigated its mechanism of action. We showed that Drs B2 inhibits the proliferation and colony formation of various human tumor cell types, and the proliferation and capillary formation of endothelial cells in vitro. Furthermore, Drs B2 inhibited tumor growth of the human prostate adenocarcinoma cell line PC3 in a xenograft model in vivo. Research on the mechanism of action of Drs B2 on tumor PC3 cells demonstrated a rapid increasing amount of cytosolic lactate dehydrogenase, no activation of caspase-3, and no changes in mitochondrial membrane potential. Confocal microscopy analysis revealed that Drs B2 can interact with the tumor cell surface, aggregate and penetrate the cells. These data together indicate that Drs B2 does not act by apoptosis but possibly by necrosis. In conclusion, Drs B2 could be considered as an interesting and promising pharmacological and therapeutic leader molecule for the treatment of cancer. PMID:23028527

Antitumor and angiostatic activities of the antimicrobial peptide dermaseptin B2.

PubMed

van Zoggel, Hanneke; Carpentier, Gilles; Dos Santos, Célia; Hamma-Kourbali, Yamina; Courty, José; Amiche, Mohamed; Delbé, Jean

2012-01-01

Recently, we have found that the skin secretions of the Amazonian tree frog Phyllomedusa bicolor contains molecules with antitumor and angiostatic activities and identified one of them as the antimicrobial peptide dermaseptin (Drs) B2. In the present study we further explored the in vitro and in vivo antitumor activity of this molecule and investigated its mechanism of action. We showed that Drs B2 inhibits the proliferation and colony formation of various human tumor cell types, and the proliferation and capillary formation of endothelial cells in vitro. Furthermore, Drs B2 inhibited tumor growth of the human prostate adenocarcinoma cell line PC3 in a xenograft model in vivo. Research on the mechanism of action of Drs B2 on tumor PC3 cells demonstrated a rapid increasing amount of cytosolic lactate dehydrogenase, no activation of caspase-3, and no changes in mitochondrial membrane potential. Confocal microscopy analysis revealed that Drs B2 can interact with the tumor cell surface, aggregate and penetrate the cells. These data together indicate that Drs B2 does not act by apoptosis but possibly by necrosis. In conclusion, Drs B2 could be considered as an interesting and promising pharmacological and therapeutic leader molecule for the treatment of cancer.

Analysis of differential protein expression by cisplatin treatment in cervical carcinoma cells.

PubMed

Yim, E-K; Lee, K-H; Kim, C-J; Park, J-S

2006-01-01

Cisplatin (cis-diaminedichloroplatinum), a DNA-damaging agent, which readily induces apoptosis in vitro, is one of the widely used anticancer drug in the treatment of human malignancies. Cisplatin has played an important role in cervical cancer management for effective chemotherapeutic regimen, but the underlying mechanisms inducing cell death at protein level are unknown. Using proteome analysis, an investigation aimed at a better understanding of the antiproliferative mechanisms by cisplatin was carried out in HeLa cervical carcinoma cells. In total, 21 protein spots were found to be differentially expressed following cisplatin treatment, of which 12 were upregulated (eg, regulator of G-protein signaling, TRAF:TNF (tumor necrosis factor) receptor-associated factor-interacting protein [I-TRAF], and cyclin-dependent kinase inhibitor p27 [p27(kip1)]) and 9 were downregulated (eg, myc proto-oncoprotein [c-myc] and proliferating cell nuclear antigen). Interestingly, we found the upregulation of proliferating cell nuclear antigen, which used molecular marker in cervical cancer screening. On the basis of proteomic data, we showed that cisplatin induced TRAF2-mediated NF-kappaB downregulation. In addition, our study demonstrated that cisplatin induced membrane death receptor-mediated and mitochondria-mediated apoptosis pathway. Our findings may offer new insights into the antiproliferative mechanism by cisplatin and its mode of action in cervical carcinoma cells.

The morphology, proliferation rate, and population doubling time factor of adipose-derived mesenchymal stem cells cultured on to non-aqueous SiO2, TiO2, and hybrid sol-gel-derived oxide coatings.

PubMed

Marycz, Krzysztof; Krzak-Roś, Justyna; Donesz-Sikorska, Anna; Śmieszek, Agnieszka

2014-11-01

In recent years, much attention has been paid to the development of tissue engineering and regenerative medicine, especially when stem cells of various sources are concerned. In addition to the interest in mesenchymal stem cells isolated from bone marrow, recently more consideration has been given to stem cells isolated from adipose tissue (AdMSCs), due to their less invasive method of collection as well as their ease of isolation and culture. However, the development of regenerative medicine requires both the application of biocompatible material and the stem cells to accelerate the regeneration. In this study, we investigated the morphology, proliferation rate index (PRi), and population doubling time factor of adipose-derived mesenchymal stem cells cultured on non-aqueous sol-gel-derived SiO2, TiO2, and SiO2/TiO2 oxide coatings. The results indicated an increase in PRi of AdMSCs when cultured on to titanium dioxide, suggesting its high attractiveness for AdMSCs. In addition, the proper morphology and the shortest doubling time of AdMSCs were observed when cultured on titanium dioxide coating. © 2014 Wiley Periodicals, Inc.

The effects of Rho-associated kinase inhibitor Y-27632 on primary human corneal endothelial cells propagated using a dual media approach.

PubMed

Peh, Gary S L; Adnan, Khadijah; George, Benjamin L; Ang, Heng-Pei; Seah, Xin-Yi; Tan, Donald T; Mehta, Jodhbir S

2015-03-16

The global shortage of donor corneas has garnered extensive interest in the development of graft alternatives suitable for endothelial keratoplasty using cultivated primary human corneal endothelial cells (CECs). We have recently described a dual media approach for the propagation of human CECs. In this work, we characterize the effects of a Rho-kinase inhibitor Y-27632 on the cultivation of CECs propagated using the dual media culture system. Seventy donor corneas deemed unsuitable for transplantation were procured for this study. We assessed the use of Y-27632 for its effect at each stage of the cell culture process, specifically for cell attachment, cell proliferation, and during both regular passaging and cryopreservation. Lastly, comparison of donor-matched CEC-cultures expanded with or without Y-27632 was also performed. Our results showed that Y-27632 significantly improved the attachment and proliferation of primary CECs. A non-significant pro-survival effect was detected during regular cellular passage when CECs were pre-treated with Y-27632, an effect that became more evident during cryopreservation. Our study showed that the inclusion of Y-27632 was beneficial for the propagation of primary CECs expanded via the dual media approach, and was able to increase overall cell yield by between 1.96 to 3.36 fold.

Comparison of the circadian variation in cell proliferation in normal and neoplastic colonic epithelial cells.

PubMed

Kennedy, M F; Tutton, P J; Barkla, D H

1985-09-15

Circadian variations in cell proliferation in normal tissues have been recognised for many years but comparable phenomena in neoplastic tissues appear not to have been reported. Adenomas and carcinomas were induced in mouse colon by injection of dimethylhydrazine (DMH) and cell proliferation in these tumors was measured stathmokinetically. In normal intestine cell proliferation is fastest at night whereas in both adenomas and carcinomas it was found to be slower at night than in the middle of the day. Chemical sympathectomy was found to abolish the circadian variation in tumor cell proliferation.

Annexin V-induced rat Leydig cell proliferation involves Ect2 via RhoA/ROCK signaling pathway.

PubMed

Jing, Jun; Chen, Li; Fu, Hai-Yan; Fan, Kai; Yao, Qi; Ge, Yi-Feng; Lu, Jin-Chun; Yao, Bing

2015-03-24

This study investigated the effect of annexin V on the proliferation of primary rat Leydig cells and the potential mechanism. Our results showed that annexin V promoted rat Leydig cell proliferation and cell cycle progression in a dose- and time-dependent manner. Increased level of annexin V also enhanced Ect2 protein expression. However, siRNA knockdown of Ect2 attenuated annexin V-induced proliferation of rat Leydig cells. Taken together, these data suggest that increased level of annexin V induced rat Leydig cell proliferation and cell cycle progression via Ect2. Since RhoA activity was increased following Ect2 activation, we further investigated whether Ect2 was involved in annexin V-induced proliferation via the RhoA/ROCK pathway, and the results showed that annexin V increased RhoA activity too, and this effect was abolished by the knockdown of Ect2. Moreover, inhibition of the RhoA/ROCK pathway by a ROCK inhibitor, Y27632, also attenuated annexin V-induced proliferation and cell cycle progression. We thus conclude that Ect2 is involved in annexin V-induced rat Leydig cell proliferation through the RhoA/ROCK pathway.

Slow and sustained nitric oxide releasing compounds inhibit multipotent vascular stem cell proliferation and differentiation without causing cell death

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

Curtis, Brandon M.; Leix, Kyle Alexander; Ji, Yajing

Highlights: • Multipotent vascular stem cells (MVSCs) proliferate and differentiate. • Nitric oxide inhibits proliferation of MVSCs. • Nitric oxide inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs). • Smooth muscle cells (SMCs) neither de-differentiate nor proliferate. - Abstract: Atherosclerosis is the leading cause of cerebral and myocardial infarction. It is believed that neointimal growth common in the later stages of atherosclerosis is a result of vascular smooth muscle cell (SMC) de-differentiation in response to endothelial injury. However, the claims of the SMC de-differentiation theory have not been substantiated by monitoring the fate of mature SMCs in response to suchmore » injuries. A recent study suggests that atherosclerosis is a consequence of multipotent vascular stem cell (MVSC) differentiation. Nitric oxide (NO) is a well-known mediator against atherosclerosis, in part because of its inhibitory effect on SMC proliferation. Using three different NO-donors, we have investigated the effects of NO on MVSC proliferation. Results indicate that NO inhibits MVSC proliferation in a concentration dependent manner. A slow and sustained delivery of NO proved to inhibit proliferation without causing cell death. On the other hand, larger, single-burst NO concentrations, inhibits proliferation, with concurrent significant cell death. Furthermore, our results indicate that endogenously produced NO inhibits MVSC differentiation to mesenchymal-like stem cells (MSCs) and subsequently to SMC as well.« less

Meclozine Facilitates Proliferation and Differentiation of Chondrocytes by Attenuating Abnormally Activated FGFR3 Signaling in Achondroplasia

PubMed Central

Matsushita, Masaki; Kitoh, Hiroshi; Ohkawara, Bisei; Mishima, Kenichi; Kaneko, Hiroshi; Ito, Mikako; Masuda, Akio; Ishiguro, Naoki; Ohno, Kinji

2013-01-01

Achondroplasia (ACH) is one of the most common skeletal dysplasias with short stature caused by gain-of-function mutations in FGFR3 encoding the fibroblast growth factor receptor 3. We used the drug repositioning strategy to identify an FDA-approved drug that suppresses abnormally activated FGFR3 signaling in ACH. We found that meclozine, an anti-histamine drug that has long been used for motion sickness, facilitates chondrocyte proliferation and mitigates loss of extracellular matrix in FGF2-treated rat chondrosarcoma (RCS) cells. Meclozine also ameliorated abnormally suppressed proliferation of human chondrosarcoma (HCS-2/8) cells that were infected with lentivirus expressing constitutively active mutants of FGFR3-K650E causing thanatophoric dysplasia, FGFR3-K650M causing SADDAN, and FGFR3-G380R causing ACH. Similarly, meclozine alleviated abnormally suppressed differentiation of ATDC5 chondrogenic cells expressing FGFR3-K650E and -G380R in micromass culture. We also confirmed that meclozine alleviates FGF2-mediated longitudinal growth inhibition of embryonic tibia in bone explant culture. Interestingly, meclozine enhanced growth of embryonic tibia in explant culture even in the absence of FGF2 treatment. Analyses of intracellular FGFR3 signaling disclosed that meclozine downregulates phosphorylation of ERK but not of MEK in FGF2-treated RCS cells. Similarly, meclozine enhanced proliferation of RCS cells expressing constitutively active mutants of MEK and RAF but not of ERK, which suggests that meclozine downregulates the FGFR3 signaling by possibly attenuating ERK phosphorylation. We used the C-natriuretic peptide (CNP) as a potent inhibitor of the FGFR3 signaling throughout our experiments, and found that meclozine was as efficient as CNP in attenuating the abnormal FGFR3 signaling. We propose that meclozine is a potential therapeutic agent for treating ACH and other FGFR3-related skeletal dysplasias. PMID:24324705

Hippo/Yap signaling controls epithelial progenitor cell proliferation and differentiation in the embryonic and adult lung

PubMed Central

Lange, Alexander W.; Sridharan, Anusha; Xu, Yan; Stripp, Barry R.; Perl, Anne-Karina; Whitsett, Jeffrey A.

2015-01-01

The Hippo/Yap pathway is a well-conserved signaling cascade that regulates cell proliferation and differentiation to control organ size and stem/progenitor cell behavior. Following airway injury, Yap was dynamically regulated in regenerating airway epithelial cells. To determine the role of Hippo signaling in the lung, the mammalian Hippo kinases, Mst1 and Mst2, were deleted in epithelial cells of the embryonic and mature mouse lung. Mst1/2 deletion in the fetal lung enhanced proliferation and inhibited sacculation and epithelial cell differentiation. The transcriptional inhibition of cell proliferation and activation of differentiation during normal perinatal lung maturation were inversely regulated following embryonic Mst1/2 deletion. Ablation of Mst1/2 from bronchiolar epithelial cells in the adult lung caused airway hyperplasia and altered differentiation. Inhibitory Yap phosphorylation was decreased and Yap nuclear localization and transcriptional targets were increased after Mst1/2 deletion, consistent with canonical Hippo/Yap signaling. YAP potentiated cell proliferation and inhibited differentiation of human bronchial epithelial cells in vitro. Loss of Mst1/2 and expression of YAP regulated transcriptional targets controlling cell proliferation and differentiation, including Ajuba LIM protein. Ajuba was required for the effects of YAP on cell proliferation in vitro. Hippo/Yap signaling regulates Ajuba and controls proliferation and differentiation of lung epithelial progenitor cells. PMID:25480985

Stem-Cell Work Yielding New Approach to Disease: Induced Pluripotent Stem-Cell Research Soars, Spurring Dreams of Clinical Applications.

PubMed

Mertz, Leslie

2016-01-01

Interest in stem cells escalated in 2006 when scientists figured out how to reprogram some specialized adult cells to assume a stem-cell-like state. Called induced pluripotent stem cells (iPSCs), these cells opened the door to a range of potential applications, including generating cells and tissues to replace those that are faulty or missing in patients with cancer, diabetes, cardiovascular disease, or other maladies (Figure 1). Visions of new treatments and even cures for debilitating and fatal illnesses proliferated, and some of that work is well under way (see "A Wealth of Research"). Now, ten years later, those visions are looking more like real possibilities as research moves from the lab to the clinic and expands toward a greater understanding of the basic science behind stem cells and its applications.

Cuttlefish bone scaffold for tissue engineering: a novel hydrothermal transformation, chemical-physical, and biological characterization.

PubMed

Battistella, Elisa; Mele, Silvia; Foltran, Ismaela; Lesci, Isidoro Giorgio; Roveri, Norberto; Sabatino, Piera; Rimondini, Lia

2012-09-27

Natural resources are receiving growing interest because of their possible conversion from a cheap and easily available material into a biomedical product. Cuttlefish bone from Sepia Officinalis was investigated in order to obtain an hydroxyapatite porous scaffold using hydrothermal transformation. Complete conversion of the previous calcium carbonate (aragonite) phase into a calcium phosphate (hydroxyapatite) phase was performed with an hydrothermal transformation at 200 °C (~ 15 atm), for four hours, with an aqueous solution of KH2PO4 in order to set the molar ratio Ca/P = 10/6 in a reactor (Parr 4382). The complete conversion was then analyzed by TGA, ATR-FTIR, x-ray diffraction, and SEM. Moreover, the material was biologically investigated with MC3T3-E1 in static cultures, using both osteogenic and maintenance media. The expression of osteogenic markers as ALP and osteocalcin and the cell proliferation were investigated. Cuttlefish bone has been successfully transformed from calcium carbonate into calcium phosphate. Biological characterization revealed that osteogenic markers are expressed using both osteogenic and maintenance conditions. Cell proliferation is influenced by the static culture condition used for this three-dimensional scaffold. The new scaffold composed by hydroxyapatite and derived for a natural source presents good biocompatibility and can be used for further investigations using dynamic cultures in order to improve cell proliferation and differentiation for bone tissue engineering.

LmaPA2G4, a Homolog of Human Ebp1, Is an Essential Gene and Inhibits Cell Proliferation in L. major

PubMed Central

Joyce, Michelle V.; Morales, Miguel A.

2014-01-01

We have identified LmaPA2G4, a homolog of the human proliferation-associated 2G4 protein (also termed Ebp1), in a phosphoproteomic screening. Multiple sequence alignment and cluster analysis revealed that LmaPA2G4 is a non-peptidase member of the M24 family of metallopeptidases. This pseudoenzyme is structurally related to methionine aminopeptidases. A null mutant system based on negative selection allowed us to demonstrate that LmaPA2G4 is an essential gene in Leishmania major. Over-expression of LmaPA2G4 did not alter cell morphology or the ability to differentiate into metacyclic and amastigote stages. Interestingly, the over-expression affected cell proliferation and virulence in mouse footpad analysis. LmaPA2G4 binds a synthetic double-stranded RNA polyriboinosinic polyribocytidylic acid [poly(I∶C)] as shown in an electrophoretic mobility shift assay (EMSA). Quantitative proteomics revealed that the over-expression of LmaPA2G4 led to accumulation of factors involved in translation initiation and elongation. Significantly, we found a strong reduction of de novo protein biosynthesis in transgenic parasites using a non-radioactive metabolic labeling assay. In conclusion, LmaPA2G4 is an essential gene and is potentially implicated in fundamental biological mechanisms, such as translation, making it an attractive target for therapeutic intervention. PMID:24421916

Inhibition of Smooth Muscle Proliferation by Urea-Based Alkanoic Acids via Peroxisome Proliferator-Activated Receptor α–Dependent Repression of Cyclin D1

PubMed Central

Ng, Valerie Y.; Morisseau, Christophe; Falck, John R.; Hammock, Bruce D.; Kroetz, Deanna L.

2007-01-01

Objective Proliferation of smooth muscle cells is implicated in cardiovascular complications. Previously, a urea-based soluble epoxide hydrolase inhibitor was shown to attenuate smooth muscle cell proliferation. We examined the possibility that urea-based alkanoic acids activate the nuclear receptor peroxisome proliferator-activated receptor α (PPARα) and the role of PPARα in smooth muscle cell proliferation. Methods and Results Alkanoic acids transactivated PPARα, induced binding of PPARα to its response element, and significantly induced the expression of PPARα-responsive genes, showing their function as PPARα agonists. Furthermore, the alkanoic acids attenuated platelet-derived growth factor–induced smooth muscle cell proliferation via repression of cyclin D1 expression. Using small interfering RNA to decrease endogenous PPARα expression, it was determined that PPARα was partially involved in the cyclin D1 repression. The antiproliferative effects of alkanoic acids may also be attributed to their inhibitory effects on soluble epoxide hydrolase, because epoxyeicosatrienoic acids alone inhibited smooth muscle cell proliferation. Conclusions These results show that attenuation of smooth muscle cell proliferation by urea-based alkanoic acids is mediated, in part, by the activation of PPARα. These acids may be useful for designing therapeutics to treat diseases characterized by excessive smooth muscle cell proliferation. PMID:16917105

Inhibition of Fatty Acid Metabolism Reduces Human Myeloma Cells Proliferation

PubMed Central

Tirado-Vélez, José Manuel; Joumady, Insaf; Sáez-Benito, Ana; Cózar-Castellano, Irene; Perdomo, Germán

2012-01-01

Multiple myeloma is a haematological malignancy characterized by the clonal proliferation of plasma cells. It has been proposed that targeting cancer cell metabolism would provide a new selective anticancer therapeutic strategy. In this work, we tested the hypothesis that inhibition of β-oxidation and de novo fatty acid synthesis would reduce cell proliferation in human myeloma cells. We evaluated the effect of etomoxir and orlistat on fatty acid metabolism, glucose metabolism, cell cycle distribution, proliferation, cell death and expression of G1/S phase regulatory proteins in myeloma cells. Etomoxir and orlistat inhibited β-oxidation and de novo fatty acid synthesis respectively in myeloma cells, without altering significantly glucose metabolism. These effects were associated with reduced cell viability and cell cycle arrest in G0/G1. Specifically, etomoxir and orlistat reduced by 40–70% myeloma cells proliferation. The combination of etomoxir and orlistat resulted in an additive inhibitory effect on cell proliferation. Orlistat induced apoptosis and sensitized RPMI-8226 cells to apoptosis induction by bortezomib, whereas apoptosis was not altered by etomoxir. Finally, the inhibitory effect of both drugs on cell proliferation was associated with reduced p21 protein levels and phosphorylation levels of retinoblastoma protein. In conclusion, inhibition of fatty acid metabolism represents a potential therapeutic approach to treat human multiple myeloma. PMID:23029529

Neural Growth Factor Stimulates Proliferation of Spinal Cord Derived-Neural Precursor/Stem Cells

PubMed Central

Han, Youngmin

2016-01-01

Objective Recently, regenerative therapies have been used in clinical trials (heart, cartilage, skeletal). We don't make use of these treatments to spinal cord injury (SCI) patients yet, but regenerative therapies are rising interest in recent study about SCI. Neural precursor/stem cell (NPSC) proliferation is a significant event in functional recovery of the central nervous system (CNS). However, brain NPSCs and spinal cord NPSCs (SC-NPSCs) have many differences including gene expression and proliferation. The purpose of this study was to investigate the influence of neural growth factor (NGF) on the proliferation of SC-NPSCs. Methods NPSCs (2×104) were suspended in 100 µL of neurobasal medium containing NGF-7S (Sigma-Aldrich) and cultured in a 96-well plate for 12 days. NPSC proliferation was analyzed five times for either concentration of NGF (0.02 and 2 ng/mL). Sixteen rats after SCI were randomly allocated into two groups. In group 1 (SCI-vehicle group, n=8), animals received 1.0 mL of the saline vehicle solution. In group 2 (SCI-NGF group, n=8), the animals received single doses of NGF (Sigma-Aldrich). A dose of 0.02 ng/mL of NGF or normal saline as a vehicle control was intra-thecally injected daily at 24 hour intervals for 7 days. For Immunohistochemistry analysis, rats were sacrificed after one week and the spinal cords were obtained. Results The elevation of cell proliferation with 0.02 ng/mL NGF was significant (p<0.05) but was not significant for 2 ng/mL NGF. The optical density was increased in the NGF 0.02 ng/mL group compared to the control group and NGF 2 ng/mL groups. The density of nestin in the SCI-NGF group was significantly increased over the SCI-vehicle group (p<0.05). High power microscopy revealed that the density of nestin in the SCI-NGF group was significantly increased over the SCI-vehicle group. Conclusion SC-NPSC proliferation is an important pathway in the functional recovery of SCI. NGF enhances SC-NPSC proliferation in vitro and in vivo. NGF may be a useful option for treatment of SCI patients pending further studies to verify the clinical applicability. PMID:27651860

Photopolymerizable chitosan-collagen hydrogels for bone tissue engineering.

PubMed

Arakawa, Christopher; Ng, Ronald; Tan, Steven; Kim, Soyon; Wu, Benjamin; Lee, Min

2017-01-01

Photopolymerizable hydrogels derived from naturally occurring polymers have attracted significant interest in tissue-engineering applications due to their excellent biocompatibility, hydrophilic nature favourable for cell ingrowth and ability to be cured in situ through a minimally invasive procedure. In this study, we developed a composite hydrogel consisting of photocrosslinkable methacrylated glycol chitosan (MeGC) and semi-interpenetrating collagen (Col) with a riboflavin photoinitiator under blue light. The incorporation of Col in MeGC hydrogels enhanced the compressive modulus and slowed the degradation rate of the hydrogels. MeGC-Col composite hydrogels significantly enhanced cellular attachment, spreading, proliferation and osteogenic differentiation of mouse bone marrow stromal cells (BMSCs) seeded on the hydrogels compared with pure MeGC hydrogels, as observed by upregulated alkaline phosphatase (ALP) activity as well as increased mineralization. Similarly, when cells were encapsulated within hydrogels, BMSCs exhibited greater proliferation, ALP activity and mineral deposits in the presence of Col. These findings demonstrate that MeGC-Col composite hydrogels may be useful in promoting bone regeneration. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

Differential protective effects of red wine polyphenol extracts (RWEs) on colon carcinogenesis.

PubMed

Mazué, Frédéric; Delmas, Dominique; Murillo, Genoveva; Saleiro, Diana; Limagne, Emeric; Latruffe, Norbert

2014-04-01

Various epidemiological studies have shown that a regular and moderate consumption of red wine is correlated with a decreased relative risk of developing coronary heart disease and cancer. These health benefits are commonly attributed to high contents of polyphenols, particularly resveratrol, representing important sources of antioxidants. However, resveratrol does not seem to be the only bioactive compound present in the wine which contains numerous other polyphenols. The present study investigates the efficiency of red wine extracts (RWEs), containing different polyphenols, on colon cancer cell proliferation in vitro and on colonic aberrant crypt foci (ACF) in vivo. Proliferation, cell cycle analysis and incidence of ACF were monitored to examine the effects of RWEs. RWEs derived from a long vinification process exhibit superior anti-proliferative activity in colon cancer cells and prevent the appearance of ACF in mice. Interestingly, quercetin and resveratrol, representing two major bio-active polyphenols, exhibit synergistic anti-proliferative effects. These data suggest that the efficacy of RWEs on colon carcinogenesis may depend on the polyphenolic content, synergistic interaction of bio-active polyphenols and modulation of cellular uptake of polyphenols.

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

Wang, Xingbing, E-mail: wangxingbing91@hotmail.com; Cheng, Qiansong; Li, Lailing

Bone marrow derived-mesenchymal stromal cells (BM-MSCs) are multipotent, nonhematopoietic progenitors in a hematopoietic microenvironment and indispensable for regulating hematopoiesis. Several studies have reported that toll-like receptors (TLRs) are expressed in mesenchymal stromal cells (MSCs) to modulate their biological functions. In this study, we investigated the possible role(s) of TLRs in mediating the hematopoiesis-supporting role of human BM-MSCs. Human BM-MSCs were analyzed for mRNA expression of TLR1-10 by reverse transcription-polymerase chain reaction. TLR1-6, but not TLR7-10 were expressed by BM-MSCs. The protein expression of TLR2 and TLR4 was also confirmed by flow cytometry. We further explored the role of TLR2 andmore » TLR4 in mediating the capacity of BM-MSCs to support the proliferation and differentiation of CD34{sup +} hematopoietic stem/progenitor cells obtained from cord blood. BM-MSCs increased proliferation of CD34{sup +} cells and promoted the differentiation towards the myeloid lineage 7 or 14 days after co-culture, as well as colony formation by those cells and the production of interleukin 1 (IL-1), IL-8, IL-11, stem cell factor (SCF), granulocyte colony-stimulating factor (CSF), macrophage CSF and granulocyte-macrophage CSF, if MSCs had been stimulated with TLR2 agonist (PAM{sub 3}CSK{sub 4}) or TLR4 agonist (LPS). Interestingly, although these effects were elevated in a different degree, a synergistic effect was not observed in BM-MSCs co-stimulated with PAM{sub 3}CSK{sub 4} and LPS. Together, our findings suggest that TLR2 and TLR4 signaling may indirectly regulate hematopoiesis by modulating BM-MSCs' functions. The increased hematopoietic proliferation and differentiation could be mediated, at least in part, by augmented hematopoiesis-related cytokine production of BM-MSCs.« less

Functional coupling of rat myometrial alpha 1-adrenergic receptors to Gh alpha/tissue transglutaminase 2 during pregnancy.

PubMed

Dupuis, Morgan; Lévy, Arlette; Mhaouty-Kodja, Sakina

2004-04-30

Gh alpha protein, which exhibits both transglutaminase and GTPase activities, represents a new class of GTP-binding proteins. In the present study, we characterized Gh alpha in rat uterine smooth muscle (myometrium) and followed its expression during pregnancy by reverse transcription-PCR and Western blot. We also measured transglutaminase and GTP binding functions and used a smooth muscle cell line to evaluate the role of Gh alpha in cell proliferation. The results show that pregnancy is associated with an up-regulation of Gh alpha expression at both the mRNA and protein level. Gh alpha induced during pregnancy is preferentially localized to the plasma membrane. This was found associated with an increased ability of plasma membrane preparations to catalyze Ca(2+)-dependent incorporation of [(3)H]putrescine into casein in vitro. In the cytosol, significant changes in the level of immunodetected Gh alpha and transglutaminase activity were seen only at term. Activation of alpha1-adrenergic receptors (alpha1-AR) enhanced photoaffinity labeling of plasma membrane Gh alpha. Moreover, the level of alpha1-AR-coupled Gh alpha increased progressively with pregnancy, which parallels the active period of myometrial cell proliferation. Overexpression of wild type Gh alpha in smooth muscle cell line DDT1-MF2 increased alpha1-AR-induced [(3)H]thymidine incorporation. A similar response was obtained in cells expressing the transglutaminase inactive mutant (C277S) of Gh alpha. Together, these findings underscore the role of Gh alpha as signal transducer of alpha1-AR-induced smooth muscle cell proliferation. In this context, pregnant rat myometrium provides an interesting physiological model to study the mechanisms underlying the regulation of the GTPase function of Gh alpha

In-vitro analysis of Quantum Molecular Resonance effects on human mesenchymal stromal cells

PubMed Central

Sella, Sabrina; Adami, Valentina; Amati, Eliana; Bernardi, Martina; Chieregato, Katia; Gatto, Pamela; Menarin, Martina; Pozzato, Alessandro; Pozzato, Gianantonio; Astori, Giuseppe

2018-01-01

Electromagnetic fields play an essential role in cellular functions interfering with cellular pathways and tissue physiology. In this context, Quantum Molecular Resonance (QMR) produces waves with a specific form at high-frequencies (4–64 MHz) and low intensity through electric fields. We evaluated the effects of QMR stimulation on bone marrow derived mesenchymal stromal cells (MSC). MSC were treated with QMR for 10 minutes for 4 consecutive days for 2 weeks at different nominal powers. Cell morphology, phenotype, multilineage differentiation, viability and proliferation were investigated. QMR effects were further investigated by cDNA microarray validated by real-time PCR. After 1 and 2 weeks of QMR treatment morphology, phenotype and multilineage differentiation were maintained and no alteration of cellular viability and proliferation were observed between treated MSC samples and controls. cDNA microarray analysis evidenced more transcriptional changes on cells treated at 40 nominal power than 80 ones. The main enrichment lists belonged to development processes, regulation of phosphorylation, regulation of cellular pathways including metabolism, kinase activity and cellular organization. Real-time PCR confirmed significant increased expression of MMP1, PLAT and ARHGAP22 genes while A2M gene showed decreased expression in treated cells compared to controls. Interestingly, differentially regulated MMP1, PLAT and A2M genes are involved in the extracellular matrix (ECM) remodelling through the fibrinolytic system that is also implicated in embryogenesis, wound healing and angiogenesis. In our model QMR-treated MSC maintained unaltered cell phenotype, viability, proliferation and the ability to differentiate into bone, cartilage and adipose tissue. Microarray analysis may suggest an involvement of QMR treatment in angiogenesis and in tissue regeneration probably through ECM remodelling. PMID:29293552

Properties of a non-bioactive fluorescent derivative of differentiation-inducing factor-3, an anti-tumor agent found in Dictyostelium discoideum

PubMed Central

Kubohara, Yuzuru; Kikuchi, Haruhisa; Matsuo, Yusuke; Oshima, Yoshiteru; Homma, Yoshimi

2014-01-01

ABSTRACT Differentiation-inducing factor-3 (DIF-3), found in the cellular slime mold Dictyostelium discoideum, and its derivatives, such as butoxy-DIF-3 (Bu-DIF-3), are potent anti-tumor agents. To investigate the activity of DIF-like molecules in tumor cells, we recently synthesized a green fluorescent DIF-3 derivative, BODIPY-DIF-3G, and analyzed its bioactivity and cellular localization. In this study, we synthesized a red (orange) fluorescent DIF-3 derivative, BODIPY-DIF-3R, and compared the cellular localization and bioactivities of the two BODIPY-DIF-3s in HeLa human cervical cancer cells. Both fluorescent compounds penetrated the extracellular membrane within 0.5 h and localized mainly to the mitochondria. In formalin-fixed cells, the two BODIPY-DIF-3s also localized to the mitochondria, indicating that the BODIPY-DIF-3s were incorporated into mitochondria independently of the mitochondrial membrane potential. After treatment for 3 days, BODIPY-DIF-3G, but not BODIPY-DIF-3R, induced mitochondrial swelling and suppressed cell proliferation. Interestingly, the swollen mitochondria were stainable with BODIPY-DIF-3G but not with BODIPY-DIF-3R. When added to isolated mitochondria in vitro, BODIPY-DIF-3G increased dose-dependently the rate of O2 consumption, but BODIPY-DIF-3R did not. These results suggest that the bioactive BODIPY-DIF-3G suppresses cell proliferation, at least in part, by altering mitochondrial activity, whereas the non-bioactive BODIPY-DIF-3R localizes to the mitochondria but does not affect mitochondrial activity or cell proliferation. PMID:24682009

Increased peroxisome proliferator-activated receptor γ activity reduces imatinib uptake and efficacy in chronic myeloid leukemia mononuclear cells

PubMed Central

Wang, Jueqiong; Lu, Liu; Kok, Chung H.; Saunders, Verity A.; Goyne, Jarrad M.; Dang, Phuong; Leclercq, Tamara M.; Hughes, Timothy P.; White, Deborah L.

2017-01-01

Imatinib is actively transported by organic cation transporter-1 (OCT-1) influx transporter, and low OCT-1 activity in diagnostic chronic myeloid leukemia blood mononuclear cells is significantly associated with poor molecular response to imatinib. Herein we report that, in diagnostic chronic myeloid leukemia mononuclear cells and BCR-ABL1+ cell lines, peroxisome proliferator-activated receptor γ agonists (GW1929, rosiglitazone, pioglitazone) significantly decrease OCT-1 activity; conversely, peroxisome proliferator-activated receptor γ antagonists (GW9662, T0070907) increase OCT-1 activity. Importantly, these effects can lead to corresponding changes in sensitivity to BCR-ABL kinase inhibition. Results were confirmed in peroxisome proliferator-activated receptor γ-transduced K562 cells. Furthermore, we identified a strong negative correlation between OCT-1 activity and peroxisome proliferator-activated receptor γ transcriptional activity in diagnostic chronic myeloid leukemia patients (n=84; P<0.0001), suggesting that peroxisome proliferator-activated receptor γ activation has a negative impact on the intracellular uptake of imatinib and consequent BCR-ABL kinase inhibition. The inter-patient variability of peroxisome proliferator-activated receptor γ activation likely accounts for the heterogeneity observed in patient OCT-1 activity at diagnosis. Recently, the peroxisome proliferator-activated receptor γ agonist pioglitazone was reported to act synergistically with imatinib, targeting the residual chronic myeloid leukemia stem cell pool. Our findings suggest that peroxisome proliferator-activated receptor γ ligands have differential effects on circulating mononuclear cells compared to stem cells. Since the effect of peroxisome proliferator-activated receptor γ activation on imatinib uptake in mononuclear cells may counteract the clinical benefit of this activation in stem cells, caution should be applied when combining these therapies, especially in patients with high peroxisome proliferator-activated receptor γ transcriptional activity. PMID:28154092

Genistein effects on stromal cells determines epithelial proliferation in endometrial co-cultures.

PubMed

Sampey, Brante P; Lewis, Terrence D; Barbier, Claire S; Makowski, Liza; Kaufman, David G

2011-06-01

Estrogen is the leading etiologic factor for endometrial cancer. Estrogen-induced proliferation of endometrial epithelial cells normally requires paracrine growth factors produced by stromal cells. Epidemiologic evidence indicates that dietary soy prevents endometrial cancer, and implicates the phytoestrogen genistein in this effect. However, results from previous studies are conflicting regarding the effects of genistein on hormone responsive cancers. The effects of estrogen and genistein on proliferation of Ishikawa (IK) endometrial adenocarcinoma cells were examined in co-cultures of IK cells with endometrial stromal cells, recapitulating the heterotypic cell-to-cell interactions observed in vivo. The roles of estrogen receptor (ER)α and ERβ were evaluated using ERα and ERβ specific agonists. ER activation and cell proliferation in the IK epithelial cells were determined by alkaline phosphatase assay and Coulter counter enumeration, respectively. Both estrogen and genistein increased estrogen receptor-induced gene activity in IK cells over a range of concentrations. Estrogen alone but not genistein increased IK proliferation in co-cultures. When primed by estrogen treatment, increasing concentrations of genistein produced a biphasic effect on IK proliferation: nM concentrations inhibited estrogen-induced proliferation while μM concentrations increased proliferation. Studies with an ERβ-specific agonist produced similar results. Genistein did not influence the effects of estrogen on IK proliferation in monoculture. Our study indicates that nutritionally relevant concentrations (nM) of genistein inhibit the proliferative effects of estrogen on endometrial adenocarcinoma cells presumably through activation of stromal cell ERβ. We believe that sub-micromolar concentrations of genistein may represent a novel adjuvant for endometrial cancer treatment and prevention. Copyright © 2011 Elsevier Inc. All rights reserved.

Modulating p56Lck in T-Cells by a Chimeric Peptide Comprising Two Functionally Different Motifs of Tip from Herpesvirus saimiri

PubMed Central

Vernot, Jean-Paul; Perdomo-Arciniegas, Ana María; Pérez-Quintero, Luis Alberto; Martínez, Diego Fernando

2015-01-01

The Lck interacting protein Tip of Herpesvirus saimiri is responsible for T-cell transformation both in vitro and in vivo. Here we designed the chimeric peptide hTip-CSKH, comprising the Lck specific interacting motif CSKH of Tip and its hydrophobic transmembrane sequence (hTip), the latter as a vector targeting lipid rafts. We found that hTip-CSKH can induce a fivefold increase in proliferation of human and Aotus sp. T-cells. Costimulation with PMA did not enhance this proliferation rate, suggesting that hTip-CSKH is sufficient and independent of further PKC stimulation. We also found that human Lck phosphorylation was increased earlier after stimulation when T-cells were incubated previously with hTip-CSKH, supporting a strong signalling and proliferative effect of the chimeric peptide. Additionally, Lck downstream signalling was evident with hTip-CSKH but not with control peptides. Importantly, hTip-CSKH could be identified in heavy lipid rafts membrane fractions, a compartment where important T-cell signalling molecules (LAT, Ras, and Lck) are present during T-cell activation. Interestingly, hTip-CSKH was inhibitory to Jurkat cells, in total agreement with the different signalling pathways and activation requirements of this leukemic cell line. These results provide the basis for the development of new compounds capable of modulating therapeutic targets present in lipid rafts. PMID:26539553

Modulating p56Lck in T-Cells by a Chimeric Peptide Comprising Two Functionally Different Motifs of Tip from Herpesvirus saimiri.

PubMed

Vernot, Jean-Paul; Perdomo-Arciniegas, Ana María; Pérez-Quintero, Luis Alberto; Martínez, Diego Fernando

2015-01-01

The Lck interacting protein Tip of Herpesvirus saimiri is responsible for T-cell transformation both in vitro and in vivo. Here we designed the chimeric peptide hTip-CSKH, comprising the Lck specific interacting motif CSKH of Tip and its hydrophobic transmembrane sequence (hTip), the latter as a vector targeting lipid rafts. We found that hTip-CSKH can induce a fivefold increase in proliferation of human and Aotus sp. T-cells. Costimulation with PMA did not enhance this proliferation rate, suggesting that hTip-CSKH is sufficient and independent of further PKC stimulation. We also found that human Lck phosphorylation was increased earlier after stimulation when T-cells were incubated previously with hTip-CSKH, supporting a strong signalling and proliferative effect of the chimeric peptide. Additionally, Lck downstream signalling was evident with hTip-CSKH but not with control peptides. Importantly, hTip-CSKH could be identified in heavy lipid rafts membrane fractions, a compartment where important T-cell signalling molecules (LAT, Ras, and Lck) are present during T-cell activation. Interestingly, hTip-CSKH was inhibitory to Jurkat cells, in total agreement with the different signalling pathways and activation requirements of this leukemic cell line. These results provide the basis for the development of new compounds capable of modulating therapeutic targets present in lipid rafts.

Neuropeptide Y stimulates retinal neural cell proliferation--involvement of nitric oxide.

PubMed

Alvaro, Ana Rita; Martins, João; Araújo, Inês M; Rosmaninho-Salgado, Joana; Ambrósio, António F; Cavadas, Cláudia

2008-06-01

Neuropeptide Y (NPY) is a 36 amino acid peptide widely present in the CNS, including the retina. Previous studies have demonstrated that NPY promotes cell proliferation of rat post-natal hippocampal and olfactory epithelium precursor cells. The aim of this work was to investigate the role of NPY on cell proliferation of rat retinal neural cells. For this purpose, primary retinal cell cultures expressing NPY, and NPY Y(1), Y(2), Y(4) and Y(5) receptors [Alvaro et al., (2007) Neurochem. Int., 50, 757] were used. NPY (10-1000 nM) stimulated cell proliferation through the activation of NPY Y(1), Y(2) and Y(5) receptors. NPY also increased the number of proliferating neuronal progenitor cells (BrdU(+)/nestin(+) cells). The intracellular mechanisms coupled to NPY receptors activation that mediate the increase in cell proliferation were also investigated. The stimulatory effect of NPY on cell proliferation was reduced by L-nitroarginine-methyl-esther (L-NAME; 500 microM), a nitric oxide synthase inhibitor, 1H-[1,2,4]oxadiazolo-[4, 3-a]quinoxalin-1-one (ODQ; 20 microM), a soluble guanylyl cyclase inhibitor or U0126 (1 microM), an inhibitor of the extracellular signal-regulated kinase 1/2 (ERK 1/2). In conclusion, NPY stimulates retinal neural cell proliferation, and this effect is mediated through nitric oxide-cyclic GMP and ERK 1/2 pathways.

Exosomes Secreted by Toxoplasma gondii-Infected L6 Cells: Their Effects on Host Cell Proliferation and Cell Cycle Changes

PubMed Central

Kim, Min Jae; Jung, Bong-Kwang; Cho, Jaeeun; Song, Hyemi; Pyo, Kyung-Ho; Lee, Ji Min; Kim, Min-Kyung; Chai, Jong-Yil

2016-01-01

Toxoplasma gondii infection induces alteration of the host cell cycle and cell proliferation. These changes are not only seen in directly invaded host cells but also in neighboring cells. We tried to identify whether this alteration can be mediated by exosomes secreted by T. gondii-infected host cells. L6 cells, a rat myoblast cell line, and RH strain of T. gondii were selected for this study. L6 cells were infected with or without T. gondii to isolate exosomes. The cellular growth patterns were identified by cell counting with trypan blue under confocal microscopy, and cell cycle changes were investigated by flow cytometry. L6 cells infected with T. gondii showed decreased proliferation compared to uninfected L6 cells and revealed a tendency to stay at S or G2/M cell phase. The treatment of exosomes isolated from T. gondii-infected cells showed attenuation of cell proliferation and slight enhancement of S phase in L6 cells. The cell cycle alteration was not as obvious as reduction of the cell proliferation by the exosome treatment. These changes were transient and disappeared at 48 hr after the exosome treatment. Microarray analysis and web-based tools indicated that various exosomal miRNAs were crucial for the regulation of target genes related to cell proliferation. Collectively, our study demonstrated that the exosomes originating from T. gondii could change the host cell proliferation and alter the host cell cycle. PMID:27180572

Ubiquitin-specific protease 14 regulates cell proliferation and apoptosis in oral squamous cell carcinoma.

PubMed

Chen, Xiangyun; Wu, Jingjing; Chen, Yitian; Ye, Dongxia; Lei, Hu; Xu, Hanzhang; Yang, Li; Wu, Yingli; Gu, Wenli

2016-10-01

Ubiquitin-specific protease 14, a deubiquitinating enzyme, has been implicated in the tumorigenesis and progression of several cancers, but its role in oral squamous cell carcinoma remains to be elucidated. The aim of this study was to explore the expression pattern and roles of Ubiquitin-specific protease 14 in the occurrence and development of oral squamous cell carcinoma. Interestingly, Ubiquitin-specific protease 14 was overexpressed in oral cancer tissues and cell lines at both mRNA and protein levels. b-AP15, a specific inhibitor of Ubiquitin-specific protease 14, significantly inhibited the growth of cancer cells and increased cell apoptosis in a dose-dependent manner. Moreover, knockdown of Ubiquitin-specific protease 14 by shRNA significantly inhibited the proliferation and migration of cancer cells in vitro. Finally, using a xenograft mouse model of oral squamous cell carcinoma, knockdown of Ubiquitin-specific protease 14 markedly inhibited tumor growth and triggered the cancer cell apoptosis in vivo, supporting previous results. In conclusion, for the first time we have demonstrated the expression pattern of Ubiquitin-specific protease 14 in oral squamous cell carcinoma and verified a relationship with tumor growth and metastasis. These results may highlight new therapeutic strategies for tumor treatment, application of Ubiquitin-specific protease 14 selective inhibitor, such as b-AP15, or knockdown by shRNA. Collectively, Ubiquitin-specific protease 14 could be a potential therapeutic target for oral squamous cell carcinoma patients. Copyright © 2016 Elsevier Ltd. All rights reserved.

Photobiomodulation of freshly isolated human adipose tissue-derived stromal vascular fraction cells by pulsed light-emitting diodes for direct clinical application.

PubMed

Priglinger, E; Maier, J; Chaudary, S; Lindner, C; Wurzer, C; Rieger, S; Redl, H; Wolbank, S; Dungel, P

2018-06-01

A highly interesting source for adult stem cells is adipose tissue, from which the stromal vascular fraction (SVF)-a heterogeneous cell population including the adipose-derived stromal/stem cells-can be obtained. To enhance the regenerative potential of freshly isolated SVF cells, low-level light therapy (LLLT) was used. The effects of pulsed blue (475 nm), green (516 nm), and red (635 nm) light from light-emitting diodes applied on freshly isolated SVF were analysed regarding cell phenotype, cell number, viability, adenosine triphosphate content, cytotoxicity, and proliferation but also osteogenic, adipogenic, and proangiogenic differentiation potential. The colony-forming unit fibroblast assay revealed a significantly increased colony size after LLLT with red light compared with untreated cells, whereas the frequency of colony-forming cells was not affected. LLLT with green and red light resulted in a stronger capacity to form vascular tubes by SVF when cultured within 3D fibrin matrices compared with untreated cells, which was corroborated by increased number and length of the single tubes and a significantly higher concentration of vascular endothelial growth factor. Our study showed beneficial effects after LLLT on the vascularization potential and proliferation capacity of SVF cells. Therefore, LLLT using pulsed light-emitting diode light might represent a new approach for activation of freshly isolated SVF cells for direct clinical application. Copyright © 2018 John Wiley & Sons, Ltd.

Preservation of high glycolytic phenotype by establishing new acute lymphoblastic leukemia cell lines at physiologic oxygen concentration

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

Sheard, Michael A., E-mail: msheard@chla.usc.edu; Ghent, Matthew V., E-mail: mattghent@gmail.com; Cabral, Daniel J., E-mail: dcabral14@gmail.com

2015-05-15

Cancer cells typically exhibit increased glycolysis and decreased mitochondrial oxidative phosphorylation, and they continue to exhibit some elevation in glycolysis even under aerobic conditions. However, it is unclear whether cancer cell lines employ a high level of glycolysis comparable to that of the original cancers from which they were derived, even if their culture conditions are changed to physiologically relevant oxygen concentrations. From three childhood acute lymphoblastic leukemia (ALL) patients we established three new pairs of cell lines in both atmospheric (20%) and physiologic (bone marrow level, 5%) oxygen concentrations. Cell lines established in 20% oxygen exhibited lower proliferation, survival,more » expression of glycolysis genes, glucose consumption, and lactate production. Interestingly, the effects of oxygen concentration used during cell line initiation were only partially reversible when established cell cultures were switched from one oxygen concentration to another for eight weeks. These observations indicate that ALL cell lines established at atmospheric oxygen concentration can exhibit relatively low levels of glycolysis and these levels are semi-permanent, suggesting that physiologic oxygen concentrations may be needed from the time of cell line initiation to preserve the high level of glycolysis commonly exhibited by leukemias in vivo. - Highlights: • Establishing new ALL cell lines in 5% oxygen resulted in higher glycolytic expression and function. • Establishing new ALL cell lines in 5% oxygen resulted in higher proliferation and lower cell death. • The divergent metabolic phenotypes selected in 5% and 20% oxygen are semi-permanent.« less

Morphological changes in human neural cells following tick-borne encephalitis virus infection.

PubMed

Růzek, Daniel; Vancová, Marie; Tesarová, Martina; Ahantarig, Arunee; Kopecký, Jan; Grubhoffer, Libor

2009-07-01

Tick-borne encephalitis (TBE) is one of the leading and most dangerous human viral neuroinfections in Europe and north-eastern Asia. The clinical manifestations include asymptomatic infections, fevers and debilitating encephalitis that might progress into chronic disease or fatal infection. To understand TBE pathology further in host nervous systems, three human neural cell lines, neuroblastoma, medulloblastoma and glioblastoma, were infected with TBE virus (TBEV). The susceptibility and virus-mediated cytopathic effect, including ultrastructural and apoptotic changes of the cells, were examined. All the neural cell lines tested were susceptible to TBEV infection. Interestingly, the neural cells produced about 100- to 10,000-fold higher virus titres than the conventional cell lines of extraneural origin, indicating the highly susceptible nature of neural cells to TBEV infection. The infection of medulloblastoma and glioblastoma cells was associated with a number of major morphological changes, including proliferation of membranes of the rough endoplasmic reticulum and extensive rearrangement of cytoskeletal structures. The TBEV-infected cells exhibited either necrotic or apoptotic morphological features. We observed ultrastructural apoptotic signs (condensation, margination and fragmentation of chromatin) and other alterations, such as vacuolation of the cytoplasm, dilatation of the endoplasmic reticulum cisternae and shrinkage of cells, accompanied by a high density of the cytoplasm. On the other hand, infected neuroblastoma cells did not exhibit proliferation of membranous structures. The virions were present in both the endoplasmic reticulum and the cytoplasm. Cells were dying preferentially by necrotic mechanisms rather than apoptosis. The neuropathological significance of these observations is discussed.

ANTIPROLIFERATIVE EFFECT OF INOSITOL HEXAPHOSPHATE ON HUMAN SKIN MELANOMA CELLS IN VITRO.

PubMed

Wawszczyk, Joanna; Kapral, Małgorzata; Lodowska, Jolanta; Jesse, Katarzyna; Hollek, Andrzej; Węglarz, Ludmiła

2015-01-01

Human malignant melanoma is a highly metastatic tumor with poor prognosis. The majority of metastatic melanomas are resistant to diverse chemotherapeutic agents. Consequently, the search for novel antimelanoma agents continues. In recent years, the interest in plants and their biologically active constituents as a source of novel potential drugs significantly increased. Inositol hexaphosphate (IP6) is a naturally occurring compound that has been shown to inhibit the growth of a wide variety of tumor cells in multiple experimental model systems. The aim of this study was to evaluate the antiproliferative and cytotoxic influence of IP6 on melanotic melanoma cells in vitro. The A2058 cells used as a model of human skin melanoma malignum were exposed to different concentrations of IP6 (0.1-5 mM) for a various period of time and their growth was determined by sulforhodamine B assay after 24, 48 and 72 h. The cytotoxicity of IP6 was measured at 24 and 72 h by XTT assay. IP6 has been found to cause dose-dependent growth suppression of A2058 melanoma cells. At low concentrations (0.1 and 0.5 mM) it did not exert any influence on the cell proliferation as compared to control cultures. Higher concentrations of IP6 (from 1 to 5 mM) had a statistically significant, suppressive effect on cell proliferation after 24 h incubation. When the experimental time period was increased up to 72 h, statistically significant inhibition of cell proliferation was monitored at all IP6 concentrations used. Data obtained from XTT assay indicated that IP6 had dose- and time-dependent cytotoxic effect on melanoma cells. The results demonstrate the antiproliferative and cytotoxic properties of IP6 in a wide range of concentrations on human A2058 melanoma cells. Hence, it can be suggested that IP6 could have a promising therapeutic significance in treating cancer.

High mobility group A1 protein modulates autophagy in cancer cells.

PubMed

Conte, Andrea; Paladino, Simona; Bianco, Gaia; Fasano, Dominga; Gerlini, Raffaele; Tornincasa, Mara; Renna, Maurizio; Fusco, Alfredo; Tramontano, Donatella; Pierantoni, Giovanna Maria

2017-11-01

High Mobility Group A1 (HMGA1) is an architectural chromatin protein whose overexpression is a feature of malignant neoplasias with a causal role in cancer initiation and progression. HMGA1 promotes tumor growth by several mechanisms, including increase of cell proliferation and survival, impairment of DNA repair and induction of chromosome instability. Autophagy is a self-degradative process that, by providing energy sources and removing damaged organelles and misfolded proteins, allows cell survival under stress conditions. On the other hand, hyper-activated autophagy can lead to non-apoptotic programmed cell death. Autophagy deregulation is a common feature of cancer cells in which has a complex role, showing either an oncogenic or tumor suppressor activity, depending on cellular context and tumor stage. Here, we report that depletion of HMGA1 perturbs autophagy by different mechanisms. HMGA1-knockdown increases autophagosome formation by constraining the activity of the mTOR pathway, a major regulator of autophagy, and transcriptionally upregulating the autophagy-initiating kinase Unc-51-like kinase 1 (ULK1). Consistently, functional experiments demonstrate that HMGA1 binds ULK1 promoter region and negatively regulates its transcription. On the other hand, the increase in autophagosomes is not associated to a proportionate increase in their maturation. Overall, the effects of HMGA1 depletion on autophagy are associated to a decrease in cell proliferation and ultimately impact on cancer cells viability. Importantly, silencing of ULK1 prevents the effects of HMGA1-knockdown on cellular proliferation, viability and autophagic activity, highlighting how these effects are, at least in part, mediated by ULK1. Interestingly, this phenomenon is not restricted to skin cancer cells, as similar results have been observed also in HeLa cells silenced for HMGA1. Taken together, these results clearly indicate HMGA1 as a key regulator of the autophagic pathway in cancer cells, thus suggesting a novel mechanism through which HMGA1 can contribute to cancer progression.

Tight Junction–Associated Signaling Pathways Modulate Cell Proliferation in Uveal Melanoma

PubMed Central

Jayagopal, Ashwath; Yang, Jin-Long; Haselton, Frederick R.; Chang, Min S.

2011-01-01

Purpose. To investigate the role of tight junction (TJ)–associated signaling pathways in the proliferation of uveal melanoma. Methods. Human uveal melanoma cell lines overexpressing the TJ molecule blood vessel epicardial substance (Bves) were generated. The effects of Bves overexpression on TJ protein expression, cell proliferation, and cell cycle distribution were quantified. In addition, localization and transcription activity of the TJ-associated protein ZO-1–associated nucleic acid binding protein (ZONAB) were evaluated using immunofluorescence and bioluminescence reporter assays to study the involvement of Bves signaling in cell proliferation-associated pathways. Results. Bves overexpression in uveal melanoma cell lines resulted in increased expression of the TJ proteins occludin and ZO-1, reduced cell proliferation, and increased sequestration of ZONAB at TJs and reduced ZONAB transcriptional activity. Conclusions. TJ proteins are present in uveal melanoma, and TJ-associated signaling pathways modulate cell signaling pathways relevant to proliferation in uveal melanoma. PMID:20861479

Matrix stiffness reverses the effect of actomyosin tension on cell proliferation.

PubMed

Mih, Justin D; Marinkovic, Aleksandar; Liu, Fei; Sharif, Asma S; Tschumperlin, Daniel J

2012-12-15

The stiffness of the extracellular matrix exerts powerful effects on cell proliferation and differentiation, but the mechanisms transducing matrix stiffness into cellular fate decisions remain poorly understood. Two widely reported responses to matrix stiffening are increases in actomyosin contractility and cell proliferation. To delineate their relationship, we modulated cytoskeletal tension in cells grown across a physiological range of matrix stiffnesses. On both synthetic and naturally derived soft matrices, and across a panel of cell types, we observed a striking reversal of the effect of inhibiting actomyosin contractility, switching from the attenuation of proliferation on rigid substrates to the robust promotion of proliferation on soft matrices. Inhibiting contractility on soft matrices decoupled proliferation from cytoskeletal tension and focal adhesion organization, but not from cell spread area. Our results demonstrate that matrix stiffness and actomyosin contractility converge on cell spreading in an unexpected fashion to control a key aspect of cell fate.

Matrix stiffness reverses the effect of actomyosin tension on cell proliferation

PubMed Central

Mih, Justin D.; Marinkovic, Aleksandar; Liu, Fei; Sharif, Asma S.; Tschumperlin, Daniel J.

2012-01-01

Summary The stiffness of the extracellular matrix exerts powerful effects on cell proliferation and differentiation, but the mechanisms transducing matrix stiffness into cellular fate decisions remain poorly understood. Two widely reported responses to matrix stiffening are increases in actomyosin contractility and cell proliferation. To delineate their relationship, we modulated cytoskeletal tension in cells grown across a physiological range of matrix stiffnesses. On both synthetic and naturally derived soft matrices, and across a panel of cell types, we observed a striking reversal of the effect of inhibiting actomyosin contractility, switching from the attenuation of proliferation on rigid substrates to the robust promotion of proliferation on soft matrices. Inhibiting contractility on soft matrices decoupled proliferation from cytoskeletal tension and focal adhesion organization, but not from cell spread area. Our results demonstrate that matrix stiffness and actomyosin contractility converge on cell spreading in an unexpected fashion to control a key aspect of cell fate. PMID:23097048

Hippo/Yap signaling controls epithelial progenitor cell proliferation and differentiation in the embryonic and adult lung.

PubMed

Lange, Alexander W; Sridharan, Anusha; Xu, Yan; Stripp, Barry R; Perl, Anne-Karina; Whitsett, Jeffrey A

2015-02-01

The Hippo/Yap pathway is a well-conserved signaling cascade that regulates cell proliferation and differentiation to control organ size and stem/progenitor cell behavior. Following airway injury, Yap was dynamically regulated in regenerating airway epithelial cells. To determine the role of Hippo signaling in the lung, the mammalian Hippo kinases, Mst1 and Mst2, were deleted in epithelial cells of the embryonic and mature mouse lung. Mst1/2 deletion in the fetal lung enhanced proliferation and inhibited sacculation and epithelial cell differentiation. The transcriptional inhibition of cell proliferation and activation of differentiation during normal perinatal lung maturation were inversely regulated following embryonic Mst1/2 deletion. Ablation of Mst1/2 from bronchiolar epithelial cells in the adult lung caused airway hyperplasia and altered differentiation. Inhibitory Yap phosphorylation was decreased and Yap nuclear localization and transcriptional targets were increased after Mst1/2 deletion, consistent with canonical Hippo/Yap signaling. YAP potentiated cell proliferation and inhibited differentiation of human bronchial epithelial cells in vitro. Loss of Mst1/2 and expression of YAP regulated transcriptional targets controlling cell proliferation and differentiation, including Ajuba LIM protein. Ajuba was required for the effects of YAP on cell proliferation in vitro. Hippo/Yap signaling regulates Ajuba and controls proliferation and differentiation of lung epithelial progenitor cells. © The Author (2014). Published by Oxford University Press on behalf of Journal of Molecular Cell Biology, IBCB, SIBS, CAS. All rights reserved.

The effect of burn injury on CD8+ and CD4+ T cells in an irradiation model of homeostatic proliferation.

PubMed

Buchanan, Ian B; Maile, Robert; Frelinger, Jeffrey A; Fair, Jeffrey H; Meyer, Anthony A; Cairns, Bruce A

2006-11-01

Homeostatic proliferation of T cells has recently been shown to be an important mechanism in the host response to infection. However, its role in the T cell response to burn injury is unknown. In this study, we examine the effect of burn injury on CD4+ and CD8+ T cell homeostatic proliferation after irradiation. Wild-type C57BL/6 female mice were irradiated with six grays ionizing radiation and 48 hours later, syngeneic whole splenocytes or purified CD4+ or CD8+ T cells labeled with carboxy-fluorescein diacetate, succinimidyl ester were adoptively transferred. Two days later, mice underwent a 20% burn injury, followed by splenocyte harvest 3 and 10 days after injury. Burn mice demonstrate increased splenic cellularity and CD8+ T cell proliferation after adoptive transfer of either purified CD8+ cells or whole spleen populations compared with unburned (sham) mice. In contrast, CD4+ T cell proliferation after burn injury is unchanged after adoptive transfer of whole spleen cells and drastically decreased after adoptive transfer of a purified CD4+ population compared with sham mice. Ten days after burn injury CD8+ T cells continue to demonstrate greater proliferation than CD4+ T cells. CD8+ T cells are more robust than CD4+ T cells in their proliferative response after burn injury. In addition, CD8+ T cell proliferation appears less reliant on other immune cells than purified CD4+ T cell proliferation. These data reiterate the importance of CD8+ T cells in the initial immune response to burn injury.

Dynamic self-organization of microwell-aggregated cellular mixtures.

PubMed

Song, Wei; Tung, Chih-Kuan; Lu, Yen-Chun; Pardo, Yehudah; Wu, Mingming; Das, Moumita; Kao, Der-I; Chen, Shuibing; Ma, Minglin

2016-06-29

Cells with different cohesive properties self-assemble in a spatiotemporal and context-dependent manner. Previous studies on cell self-organization mainly focused on the spontaneous structural development within a short period of time during which the cell numbers remained constant. However the effect of cell proliferation over time on the self-organization of cells is largely unexplored. Here, we studied the spatiotemporal dynamics of self-organization of a co-culture of MDA-MB-231 and MCF10A cells seeded in a well defined space (i.e. non-adherent microfabricated wells). When cell-growth was chemically inhibited, high cohesive MCF10A cells formed a core surrounded by low cohesive MDA-MB-231 cells on the periphery, consistent with the differential adhesion hypothesis (DAH). Interestingly, this aggregate morphology was completely inverted when the cells were free to grow. At an initial seeding ratio of 1 : 1 (MDA-MB-231 : MCF10A), the fast growing MCF10A cells segregated in the periphery while the slow growing MDA-MB-231 cells stayed in the core. Another morphology developed at an inequal seeding ratio (4 : 1), that is, the cell mixtures developed a side-by-side aggregate morphology. We conclude that the cell self-organization depends not only on the cell cohesive properties but also on the cell seeding ratio and proliferation. Furthermore, by taking advantage of the cell self-organization, we purified human embryonic stem cells-derived pancreatic progenitors (hESCs-PPs) from co-cultured feeder cells without using any additional tools or labels.

Differential role of PTEN in transforming growth factor β (TGF-β) effects on proliferation and migration in prostate cancer cells.

PubMed

Kimbrough-Allah, Mawiyah N; Millena, Ana C; Khan, Shafiq A

2018-04-01

Transforming growth factor-β (TGF-β) acts as a tumor suppressor in normal epithelial cells but as a tumor promoter in advanced prostate cancer cells. PI3-kinase pathway mediates TGF-β effects on prostate cancer cell migration and invasion. PTEN inhibits PI3-kinase pathway and is frequently mutated in prostate cancers. We investigated possible role(s) of PTEN in TGF-β effects on proliferation and migration in prostate cancer cells. Expression of PTEN mRNA and proteins were determined using RT-PCR and Western blotting in RWPE1 and DU145 cells. We also studied the role of PTEN in TGF-β effects on cell proliferation and migration in DU145 cells after transient silencing of endogenous PTEN. Conversely, we determined the role of PTEN in cell proliferation and migration after over-expression of PTEN in PC3 cells which lack endogenous PTEN. TGF-β1 and TGF-β3 had no effect on PTEN mRNA levels but both isoforms increased PTEN protein levels in DU145 and RWPE1 cells indicating that PTEN may mediate TGF-β effects on cell proliferation. Knockdown of PTEN in DU145 cells resulted in significant increase in cell proliferation which was not affected by TGF-β isoforms. PTEN overexpression in PC3 cells inhibited cell proliferation. Knockdown of endogenous PTEN enhanced cell migration in DU145 cells, whereas PTEN overexpression reduced migration in PC3 cells and reduced phosphorylation of AKT in response to TGF-β. We conclude that PTEN plays a role in inhibitory effects of TGF-β on cell proliferation whereas its absence may enhance TGF-β effects on activation of PI3-kinase pathway and cell migration. © 2018 Wiley Periodicals, Inc.

Phenolic Compounds in Extra Virgin Olive Oil Stimulate Human Osteoblastic Cell Proliferation.

PubMed

García-Martínez, Olga; De Luna-Bertos, Elvira; Ramos-Torrecillas, Javier; Ruiz, Concepción; Milia, Egle; Lorenzo, María Luisa; Jimenez, Brigida; Sánchez-Ortiz, Araceli; Rivas, Ana

2016-01-01

In this study, we aimed to clarify the effects of phenolic compounds and extracts from different extra virgin olive oil (EVOO) varieties obtained from fruits of different ripening stages on osteoblast cells (MG-63) proliferation. Cell proliferation was increased by hydroxytyrosol, luteolin, apigenin, p-coumaric, caffeic, and ferulic acids by approximately 11-16%, as compared with controls that were treated with one vehicle alone, while (+)-pinoresinol, oleuropein, sinapic, vanillic acid and derivative (vanillin) did not affect cell proliferation. All phenolic extracts stimulated MG-63 cell growth, and they induced higher cell proliferation rates than individual compounds. The most effective EVOO phenolic extracts were those obtained from the Picual variety, as they significantly increased cell proliferation by 18-22%. Conversely, Arbequina phenolic extracts increased cell proliferation by 9-13%. A decline in osteoblast proliferation was observed in oils obtained from olive fruits collected at the end of the harvest period, as their total phenolic content decreases at this late stage. Further research on the signaling pathways of olive oil phenolic compounds involved in the processes and their metabolism should be carried out to develop new interventions and adjuvant therapies using EVOO for bone health (i.e.osteoporosis) in adulthood and the elderly.

Extracellular ATP inhibits Schwann cell dedifferentiation and proliferation in an ex vivo model of Wallerian degeneration

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

Shin, Youn Ho; Lee, Seo Jin; Jung, Junyang, E-mail: jjung@khu.ac.kr

Highlights: Black-Right-Pointing-Pointer ATP-treated sciatic explants shows the decreased expression of p75NGFR. Black-Right-Pointing-Pointer Extracellular ATP inhibits the expression of phospho-ERK1/2. Black-Right-Pointing-Pointer Lysosomal exocytosis is involved in Schwann cell dedifferentiation. Black-Right-Pointing-Pointer Extracellular ATP blocks Schwann cell proliferation in sciatic explants. -- Abstract: After nerve injury, Schwann cells proliferate and revert to a phenotype that supports nerve regeneration. This phenotype-changing process can be viewed as Schwann cell dedifferentiation. Here, we investigated the role of extracellular ATP in Schwann cell dedifferentiation and proliferation during Wallerian degeneration. Using several markers of Schwann cell dedifferentiation and proliferation in sciatic explants, we found that extracellular ATP inhibitsmore » Schwann cell dedifferentiation and proliferation during Wallerian degeneration. Furthermore, the blockage of lysosomal exocytosis in ATP-treated sciatic explants is sufficient to induce Schwann cell dedifferentiation. Together, these findings suggest that ATP-induced lysosomal exocytosis may be involved in Schwann cell dedifferentiation.« less

Divergent Kinetics of Proliferating T Cell Subsets in Simian Immunodeficiency Virus (SIV) Infection: SIV Eliminates the “First Responder” CD4+ T Cells in Primary Infection

PubMed Central

Wang, Xiaolei; Xu, Huanbin; Pahar, Bapi; Lackner, Andrew A.

2013-01-01

Although increased lymphocyte turnover in chronic human immunodeficiency virus and simian immunodeficiency virus (SIV) infection has been reported in blood, there is little information on cell turnover in tissues, particularly in primary SIV infection. Here we examined the levels of proliferating T cell subsets in mucosal and peripheral lymphoid tissues of adult macaques throughout SIV infection. To specifically label cells in S-phase division, all animals were inoculated with bromodeoxyuridine 24 h prior to sampling. In healthy macaques, the highest levels of proliferating CD4+ and CD8+ T cells were in blood and, to a lesser extent, in spleen. Substantial percentages of proliferating cells were also found in intestinal tissues, including the jejunum, ileum, and colon, but very few proliferating cells were detected in lymph nodes (axillary and mesenteric). Moreover, essentially all proliferating T cells in uninfected animals coexpressed CD95 and many coexpressed CCR5 in the tissues examined. Confocal microscopy also demonstrated that proliferating cells were substantial viral target cells for SIV infection and viral replication. After acute SIV infection, percentages of proliferating CD4+ and CD8+ T cells were significantly higher in tissues of chronically infected macaques and macaques with AIDS than in those of the controls. Surprisingly, however, we found that proliferating CD4+ T cells were selectively decreased in very early infection (8 to 10 days postinoculation [dpi]). In contrast, levels of proliferating CD8+ T cells rapidly increased after SIV infection, peaked by 13 to 21 dpi, and thereafter remained significantly higher than those in the controls. Taken together, these findings suggest that SIV selectively infects and destroys dividing, nonspecific CD4+ T cells in acute infection, resulting in homeostatic changes and perhaps continuing loss of replication capacity to respond to nonspecific and, later, SIV-specific antigens. PMID:23596288

Divergent kinetics of proliferating T cell subsets in simian immunodeficiency virus (SIV) infection: SIV eliminates the "first responder" CD4+ T cells in primary infection.

PubMed

Wang, Xiaolei; Xu, Huanbin; Pahar, Bapi; Lackner, Andrew A; Veazey, Ronald S

2013-06-01

Although increased lymphocyte turnover in chronic human immunodeficiency virus and simian immunodeficiency virus (SIV) infection has been reported in blood, there is little information on cell turnover in tissues, particularly in primary SIV infection. Here we examined the levels of proliferating T cell subsets in mucosal and peripheral lymphoid tissues of adult macaques throughout SIV infection. To specifically label cells in S-phase division, all animals were inoculated with bromodeoxyuridine 24 h prior to sampling. In healthy macaques, the highest levels of proliferating CD4(+) and CD8(+) T cells were in blood and, to a lesser extent, in spleen. Substantial percentages of proliferating cells were also found in intestinal tissues, including the jejunum, ileum, and colon, but very few proliferating cells were detected in lymph nodes (axillary and mesenteric). Moreover, essentially all proliferating T cells in uninfected animals coexpressed CD95 and many coexpressed CCR5 in the tissues examined. Confocal microscopy also demonstrated that proliferating cells were substantial viral target cells for SIV infection and viral replication. After acute SIV infection, percentages of proliferating CD4(+) and CD8(+) T cells were significantly higher in tissues of chronically infected macaques and macaques with AIDS than in those of the controls. Surprisingly, however, we found that proliferating CD4(+) T cells were selectively decreased in very early infection (8 to 10 days postinoculation [dpi]). In contrast, levels of proliferating CD8(+) T cells rapidly increased after SIV infection, peaked by 13 to 21 dpi, and thereafter remained significantly higher than those in the controls. Taken together, these findings suggest that SIV selectively infects and destroys dividing, nonspecific CD4(+) T cells in acute infection, resulting in homeostatic changes and perhaps continuing loss of replication capacity to respond to nonspecific and, later, SIV-specific antigens.

Further studies on the effect of adenosine cyclic monophosphate derivatives on cell proliferation in the jejunal crypts of rat.

PubMed

Tutton, P J; Barkla, D H

1982-01-01

1. Cell proliferation in the jejunal crypt epithelium of rat was measured using a stathmokinetic technique. 2. Sodium butyrate was found to promote jejunal crypt cell proliferation. 3. N6, O2'-Dibutyryl cyclic adenosine monophosphate (cAMP), N6-monobutyryl-cAMP and N6-monobutyryl-8-bromo-cAMP were found to inhibit cell proliferation when compared to sodium butyrate treated tissues. 4. 8-Chlorophenylthio-cAMP was found to inhibit cell division when compared to untreated animals. 5. O2'-Monobutyryl cAMP and 8-bromo-cAMP were not found to inhibit cell proliferation.

Anti-inflammatory activity of chloroquine and amodiaquine through p21-mediated suppression of T cell proliferation and Th1 cell differentiation

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

Oh, Sera; Shin, Ji Hyun; Jang, Eun Jung

Chloroquine (CQ) and amodiaquine (AQ) have been used for treating or preventing malaria for decades, and their application has expanded into treating inflammatory disease in humans. CQ and AQ are applicable for controlling rheumatoid arthritis, but their molecular mechanisms of anti-inflammatory activity remain to be elucidated. In this study, we examined the effects of CQ and AQ on T cell activation and T cell-mediated immune response. CQ had no significant effect on T cell numbers, but decreased the population of T cells with a high division rate. However, AQ treatment significantly increased the number of cells with low division ratesmore » and eliminated cells with high division rates, resulting in the inhibition of T cell proliferation triggered by T cell receptor stimulation, of which inhibition occurred in developing effector T helper and regulatory T cells, regardless of the different exogenous cytokines. Interestingly, the cyclin-dependent kinase inhibitor p21 was significantly and dose-dependently increased by CQ, and more potently by AQ, while other cell cycle regulators were unchanged. Both CQ and AQ elevated the transcription level of p21 though the activation of p53, but also blocked p21 protein degradation in the presence of cycloheximide, causing p21 protein accumulation mainly in the nucleus. Sustained treatment of developing T cells with either CQ or AQ suppressed IFN-γ production in a dose dependent manner and potently inhibited the differentiation of IFN-γ-producing Th1 cells. These results demonstrate that CQ and AQ increase the expression level of p21 and inhibit T cell proliferation and the development of IFN-γ-producing Th1 cells, thereby revealing beneficial roles in treating a wide range of chronic inflammatory diseases mediated by inflammatory T cells. -- Highlights: •T cell division rates are suppressed by chloroquine and amodiaquine treatment. •Chloroquine and amodiaquine potently increased the p21 expression. •The p21 induction is regulated at the transcriptional and post-translational level. •Chloroquine and amodiaquine suppress inflammatory IFN-γ production.« less

Effect of molecular weight and concentration of hyaluronan on cell proliferation and osteogenic differentiation in vitro

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

Zhao, Ningbo, E-mail: curl-zhao@163.com; Wang, Xin, E-mail: 394041230@qq.com; Qin, Lei, E-mail: qinlei30@126.com

Hyaluronan (HA), the simplest glycosaminoglycan and a major component of the extracellular matrix, exists in various tissues. It is involved in some critical biological procedures, including cellular signaling, cell adhesion and proliferation, and cell differentiation. The effect of molecular weight (MW) and concentration of HA on cell proliferation and differentiation was controversial. In this study, we investigated the effect of MW and concentration of HA on the proliferation and osteogenic differentiation of rabbit bone marrow-derived stem cells in vitro. Results showed that high MW HA decreased the cell adhesion rate in a concentration-dependant manner. The cell adhesion rate was decreased bymore » increasing MW of HA. Cell proliferation was significantly enhanced by low MW HA (P < 0.05). The factorial analysis indicated that MW and concentration had an interactive effect on the cell adhesion rate and cell proliferation (P < 0.05). High MW HA increased the mRNA expressions of ALP, RUNX-2 and OCN. The higher the MW was, the higher the mRNA expressions were. The factorial analysis indicated that MW and concentration had an interactive effect on ALP mRNA expression (P < 0.05). HA of higher MW and higher concentration promoted bone formation. These findings provide some useful information in understanding the mechanism underlying the effect of MW and concentration of HA on cell proliferation and differentiation. - Highlights: • Effect of hyaluronan on cell proliferation and differentiation is evaluated in vitro. • Hyaluronan of low molecular weight increases cell proliferation. • Hyaluronan of high molecular weight promotes cell osteogenic differentiation. • Molecular weight and concentration of hyaluronan show interactive effect.« less

The selection of light emitting diode irradiation parameters for stimulation of human mesenchymal stem cells proliferation

NASA Astrophysics Data System (ADS)

Lewandowski, Rafał; Trafny, ElŻbieta A.; Stepińska, Małgorzata; Gietka, Andrzej; Kotowski, Paweł; Dobrzyńska, Monika; Łapiński, Mariusz P.

2016-12-01

Human mesenchymal stem cells (hMSCs) with their vast differentiation potential are very useful for cell-based regenerative medicine. To achieve sufficient numbers of cells for tissue engineering, many different methods have been used to reach the effective increase of cell proliferation. Low-energy red light provided by light emitting diodes (LEDs) have been recently introduced as a method that promoted biomodulation and proliferation of hMSCs in vitro. The purpose of this study was to find the optimum stimulatory dosimetric parameters of LED (630 nm) irradiation on the hMSCs proliferation. The energy density was 2, 3, 4, 10, 20 J/cm2 and the power density used was 7, 17 or 30 mW/cm2. Human MSCs were irradiated with single or triple exposures daily at room temperature and the cell proliferation rate was evaluated during nine days after irradiation. The results showed that after irradiation 4 J/cm2 and 17 mW/cm2 at a single dose the proliferation rate of hMSCs increased on day 5 and 9 (13% and 7%, respectively) when compared to nonirradiated cells. However, triple LED irradiation under the same parameters resulted in the decline in the cell proliferation rate on day 5, but the proliferation rate was at the same level on day 9, when compared with the cell proliferation after irradiation with a single dose. The effect of a single dose irradiation with 4 J/cm2 and 17 mW/cm2 on the proliferation of cells was the highest when the cells were irradiated in phosphate-buffered saline (PBS) instead of MSCGM culture medium.

NFAT5 promotes proliferation and migration of lung adenocarcinoma cells in part through regulating AQP5 expression

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

Guo, Kai, E-mail: gk161@163.com; Department of Respiration, 161th Hospital, PLA, Wuhan 430015; Jin, Faguang, E-mail: jinfag@fmmu.edu.cn

2015-09-25

The osmoregulated transcription factor nuclear factor of activated T-cells 5(NFAT5), has been found to play important roles in the development of many kinds of human cancers, including breast cancer, colon carcinoma, renal cell carcinoma and melanoma. The aim of the present study was to determine whether NFAT5 is involved in the proliferation and migration of lung adenocarcinoma cells. We found that NFAT5 was upregulated in lung adenocarcinoma cells and knockdown of NFAT5 decreased proliferation and migration of the cells, accompanied by a significant reduction in the expression of AQP5. AQP5 was upregulated in lung adenocarcinoma cells and knockdown of AQP5more » also inhibited proliferation and migration of the cells as knockdown of NFAT5 did. Moreover, overexpression of NFAT5 promoted proliferation and migration of lung adenocarcinoma cells, accompanied by a significant increase in the expression of AQP5. These results indicate that NFAT5 plays important roles in proliferation and migration of human lung adenocarcinoma cells through regulating AQP5 expression, providing a new therapeutic option for lung adenocarcinoma therapy. - Highlights: • NFAT5 expression is higher in lung adenocarcinoma cells compared with normal cells. • NFAT5 knockdown decreases proliferation and migration of lung adenocarcinoma cells. • Knockdown of NFAT5 reduces AQP5 expression in human lung adenocarcinoma cells. • Overexpression of NFAT5 promotes proliferation and migration of lung adenocarcinoma cells. • Overexpression of NFAT5 increases AQP5 expression in human lung adenocarcinoma cells.« less

Defective prolactin signaling impairs pancreatic β-cell development during the perinatal period

PubMed Central

Auffret, Julien; Freemark, Michael; Carré, Nadège; Mathieu, Yves; Tourrel-Cuzin, Cécile; Lombès, Marc; Movassat, Jamileh

2013-01-01

Prolactin (PRL) and placental lactogens stimulate β-cell replication and insulin production in pancreatic islets and insulinoma cells through binding to the PRL receptor (PRLR). However, the contribution of PRLR signaling to β-cell ontogeny and function in perinatal life and the effects of the lactogens on adaptive islet growth are poorly understood. We provide evidence that expansion of β-cell mass during both embryogenesis and the postnatal period is impaired in the PRLR−/− mouse model. PRLR−/− newborns display a 30% reduction of β-cell mass, consistent with reduced proliferation index at E18.5. PRL stimulates leucine incorporation and S6 kinase phosphorylation in INS-1 cells, supporting a role for β-cell mTOR signaling in PRL action. Interestingly, a defect in the development of acini is also observed in absence of PRLR signaling, with a sharp decline in cellular size in both endocrine and exocrine compartments. Of note, a decrease in levels of IGF-II, a PRL target, in the Goto-Kakizaki (GK) rat, a spontaneous model of type 2 diabetes, is associated with a lack of PRL-mediated β-cell proliferation in embryonic pancreatic buds. Reduced pancreatic IGF-II expression in both rat and mouse models suggests that this factor may constitute a molecular link between PRL signaling and cell ontogenesis. Together, these results provide evidence that PRL signaling is essential for pancreas ontogenesis during the critical perinatal window responsible for establishing functional β-cell reserve. PMID:24064341

Effect of endocannabinoid signalling on cell fate: life, death, differentiation and proliferation of brain cells.

PubMed

Garcia-Arencibia, Moises; Molina-Holgado, Eduardo; Molina-Holgado, Francisco

2018-05-24

Cell fate events are regulated by different endogenous developmental factors such as the cell micro-environment, external or remote signals and epigenetic factors. Among the many regulatory factors, endocannabinoid-associated signalling pathways are known to conduct several of these events in the developing nervous system and in the adult brain. Interestingly, endocannabinoids exert modulatory actions in both physiological and pathological conditions. Endocannabinoid signalling can promote cell survival by acting on non-transformed brain cells (neurons, astrocytes or oligodendrocytes) and can have either a protumoural or antitumoural effect on transformed cells. Moreover, endocannabinoids are able to attenuate the detrimental effects on neurogenesis and neuroinflammation associated with ageing. Thus, the endocannabinoid system emerges as an important regulator of cell fate, controlling cell survival/cell death decisions depending on the cell type and its environment. © 2018 The British Pharmacological Society.

Zinc Promotes Adipose-Derived Mesenchymal Stem Cell Proliferation and Differentiation towards a Neuronal Fate.

PubMed

Moon, Mi-Young; Kim, Hyun Jung; Choi, Bo Young; Sohn, Min; Chung, Tae Nyoung; Suh, Sang Won

2018-01-01

Zinc is an essential element required for cell division, migration, and proliferation. Under zinc-deficient conditions, proliferation and differentiation of neural progenitors are significantly impaired. Adipose-derived mesenchymal stem cells (AD-MSCs) are multipotent stem cells that can differentiate into neurons. The aim of this study was to evaluate the effect of zinc on AD-MSC proliferation and differentiation. We initially examined the effect of zinc on stem cell proliferation at the undifferentiated stage. AD-MSCs showed high proliferation rates on day 6 in 30  μ M and 100  μ M of ZnCl 2 . Zinc chelation inhibited AD-MSC proliferation via downregulation of ERK1/2 activity. We then assessed whether zinc was involved in cell migration and neurite outgrowth during differentiation. After three days of neuronal differentiation, TUJ-1-positive cells were observed, implying that AD-MSCs had differentiated into early neuron or neuron-like cells. Neurite outgrowth was increased in the zinc-treated group, while the CaEDTA-treated group showed diminished, shrunken neurites. Furthermore, we showed that zinc promoted neurite outgrowth via the inactivation of RhoA and led to the induction of neuronal gene expression (MAP2 and nestin) in differentiated stem cells. Taken together, zinc promoted AD-MSC proliferation and affected neuronal differentiation, mainly by increasing neurite outgrowth.

Paracrine influence of human perivascular cells on the proliferation of adenocarcinoma alveolar epithelial cells.

PubMed

Kim, Eunbi; Na, Sunghun; An, Borim; Yang, Se-Ran; Kim, Woo Jin; Ha, Kwon-Soo; Han, Eun-Taek; Park, Won Sun; Lee, Chang-Min; Lee, Ji Yoon; Lee, Seung-Joon; Hong, Seok-Ho

2017-03-01

Understanding the crosstalk mechanisms between perivascular cells (PVCs) and cancer cells might be beneficial in preventing cancer development and metastasis. In this study, we investigated the paracrine influence of PVCs derived from human umbilical cords on the proliferation of lung adenocarcinoma epithelial cells (A549) and erythroleukemia cells (TF-1α and K562) in vitro using Transwell® co-culture systems. PVCs promoted the proliferation of A549 cells without inducing morphological changes, but had no effect on the proliferation of TF-1α and K562 cells. To identify the factors secreted from PVCs, conditioned media harvested from PVC cultures were analyzed by antibody arrays. We identified a set of cytokines, including persephin (PSPN), a neurotrophic factor, and a key regulator of oral squamous cell carcinoma progression. Supplementation with PSPN significantly increased the proliferation of A549 cells. These results suggested that PVCs produced a differential effect on the proliferation of cancer cells in a cell-type dependent manner. Further, secretome analyses of PVCs and the elucidation of the molecular mechanisms could facilitate the discovery of therapeutic target(s) for lung cancer.

Estradiol and corticosterone stimulate the proliferation of a GH cell line, MtT/S: Proliferation of growth hormone cells.

PubMed

Nogami, Haruo; Hiraoka, Yoshiki; Aiso, Sadakazu

2016-08-01

Estrogens are known as a potent growth-stimulator of the anterior pituitary cells such as prolactin cells and somatomammotroph cell lines, while glucocorticoids often inhibit cellular proliferation in the pituitary gland as well as in the extra-pituitary tissues. In this study, the involvement of these steroid hormones in the regulation of proliferation was examined in the MtT/S cells, secreting growth hormone (GH). Effects of estrogens and glucocorticoids were examined in MtT/S cells grown in the medium containing dextran-coated charcoal treated serum. The relative cell density after culture was estimated by the Cell Titer-Glo Luminescent Cell Viability Assay System, and the proliferation rate was determined by the BrdU incorporation method. The mRNA levels were determined by real-time PCR. Estradiol and the specific agonist for both estrogen receptor (ER) α and ERβ stimulated MtT/S growth at a dose dependent manner. The membrane impermeable estrogen, 17β-estradiol-bovine serum albumin conjugate also stimulated the MtT/S proliferation. The effects of all estrogens were inhibited by an estrogen receptor antagonist, ICI182780. Corticosterone stimulated the proliferation of MtT/S cells at doses lower than 10nM without stimulating GH gene transcription, whereas it did not change the proliferation rate at 1μM. The effects of corticosterone were inhibited by glucocorticoid receptor inhibitor, RU486, but not by the mineralocorticoid receptor antagonist, spironolactone. Both estrogens and glucocorticoids were found to stimulate the proliferation of MtT/S, increasing the mRNA expression of cyclins D1, D3, and E. The results suggest that estrogens and glucocorticoids may be involved in the mechanisms responsible for the proliferation of GH cells in the course of pituitary development, to maintain the population of GH cells in the adult pituitary gland, and also in the promotion of GH cell tumors. Copyright © 2016 Elsevier Ltd. All rights reserved.

[Overexpression of inhibitor of β-catenin and T cell factor (ICAT) promotes proliferation and migration of cervical cancer Caski cells].

PubMed

Jiang, Yayun; Wang, Ting; Wang, Jinshu; Xia, Jing; Gou, Liyao; Liu, Mengyao; Zhang, Yan

2016-11-01

Objective To investigate the effect of overexpressed inhibitor of β-catenin and T cell factor (ICAT) on the proliferation and migration of human cervical cancer Caski cells. Methods Caski cells were transfected with ICAT recombinant adenovirus (AdICAT). The levels of ICAT mRNA and protein were detected by quantitative real-time PCR (qRT-PCR) and Western blotting, respectively. Effect of ICAT overexpression on proliferation, cell cycle and migration in Caski cells was respectively evaluated by MTT assay, flow cytometry and Transwell TM migration assays. Results The expression of ICAT remarkably increased in Caski cells after AdICAT infection. Overexpression of ICAT promoted Caski cells' proliferation, arrested the cell cycle in the S phase and enhanced cell migration. Conclusion Overexpression of ICAT can promote the proliferation and migration of Caski cervical cancer cells.

Wnt5a Increases Properties of Lung Cancer Stem Cells and Resistance to Cisplatin through Activation of Wnt5a/PKC Signaling Pathway

PubMed Central

Yang, Jiali; Zhang, Kangjian; Wu, Jing; Shi, Juan; Xue, Jing; Li, Jing; Zhu, Yongzhao; Wei, Jun

2016-01-01

The development of chemoresistance to cisplatin regimens causes a poor prognosis in patients with advanced NSCLC. The role of noncanonical Wnt signaling in the regulation of properties of lung cancer stem cells and chemoresistance was interrogated, by accessing capacities of cell proliferation, migration, invasion, and clonogenicity as well as the apoptosis in A549 cell lines and cisplatin-resistant A549 cells treated with Wnt5a conditional medium or protein kinase C (PKC) inhibitor GF109203X. Results showed that the noncanonical Wnt signaling ligand, Wnt5a, could promote the proliferation, migration, invasion, and colony formation in A549 lung adenocarcinoma cells and cisplatin-resistant A549/DDP cells and increase the fraction of ALDH-positive cell in A549/DDP cells. An exposure of cells to Wnt5a led to a significant reduction of A549/DDP cell apoptosis but not A549 cells. An addition of GF109203X could both strikingly increase the baseline apoptosis and resensitize the Wnt5a-inhibited cell apoptosis. Interestingly, an inhibition of Wnt/PKC signaling pathway could reduce properties of lung cancer stem cells, promote cell apoptosis, and resensitize cisplatin-resistant cells to cisplatin via a caspase/AIF-dependent pathway. These data thus suggested that the Wnt5a could promote lung cancer cell mobility and cisplatin-resistance through a Wnt/PKC signaling pathway and a blockage of this signaling may be an alternative therapeutic strategy for NSCLC patients with resistance to chemotherapies. PMID:27895670

Changes in Reactivity In Vitro of CD4+CD25+ and CD4+CD25− T Cell Subsets in Transplant Tolerance

PubMed Central

Hall, Bruce M.; Robinson, Catherine M.; Plain, Karren M.; Verma, Nirupama D.; Tran, Giang T.; Nomura, Masaru; Carter, Nicole; Boyd, Rochelle; Hodgkinson, Suzanne J.

2017-01-01

Transplant tolerance induced in adult animals is mediated by alloantigen-specific CD4+CD25+ T cells, yet in many models, proliferation of CD4+ T cells from hosts tolerant to specific-alloantigen in vitro is not impaired. To identify changes that may diagnose tolerance, changes in the patterns of proliferation of CD4+, CD4+CD25+, and CD4+CD25− T cells from DA rats tolerant to Piebald Virol Glaxo rat strain (PVG) cardiac allografts and from naïve DA rats were examined. Proliferation of CD4+ T cells from both naïve and tolerant hosts was similar to both PVG and Lewis stimulator cells. In mixed lymphocyte culture to PVG, proliferation of naïve CD4+CD25− T cells was greater than naïve CD4+ T cells. In contrast, proliferation of CD4+CD25− T cells from tolerant hosts to specific-donor PVG was not greater than CD4+ T cells, whereas their response to Lewis and self-DA was greater than CD4+ T cells. Paradoxically, CD4+CD25+ T cells from tolerant hosts did not proliferate to PVG, but did to Lewis, whereas naïve CD4+CD25+ T cells proliferate to both PVG and Lewis but not to self-DA. CD4+CD25+ T cells from tolerant, but not naïve hosts, expressed receptors for interferon (IFN)-γ and IL-5 and these cytokines promoted their proliferation to specific-alloantigen PVG but not to Lewis or self-DA. We identified several differences in the patterns of proliferation to specific-donor alloantigen between cells from tolerant and naïve hosts. Most relevant is that CD4+CD25+ T cells from tolerant hosts failed to proliferate or suppress to specific donor in the absence of either IFN-γ or IL-5. The proliferation to third-party and self of each cell population from tolerant and naïve hosts was similar and not affected by IFN-γ or IL-5. Our findings suggest CD4+CD25+ T cells that mediate transplant tolerance depend on IFN−γ or IL-5 from alloactivated Th1 and Th2 cells. PMID:28878770

Influence of Fe3O4 Nanoparticles in Hydroxyapatite Scaffolds on Proliferation of Primary Human Fibroblast Cells

NASA Astrophysics Data System (ADS)

Maleki-Ghaleh, H.; Aghaie, E.; Nadernezhad, A.; Zargarzadeh, M.; Khakzad, A.; Shakeri, M. S.; Beygi Khosrowshahi, Y.; Siadati, M. H.

2016-06-01

Modern techniques for expanding stem cells play a substantial role in tissue engineering: the raw material that facilitates regeneration of damaged tissues and treats diseases. The environmental conditions and bioprocessing methods are the primary determinants of the rate of cultured stem cell proliferation. Bioceramic scaffolds made of calcium phosphate are effective substrates for optimal cell proliferation. The present study investigates the effects of two bioceramic scaffolds on proliferating cells in culture media. One scaffold was made of hydroxyapatite and the other was a mixture of hydroxyapatite and ferromagnetic material (Fe3O4 nanoparticles). Disk-shaped (10 mm × 2 mm) samples of the two scaffolds were prepared. Primary human fibroblast proliferation was 1.8- and 2.5-fold faster, respectively, when cultured in the presence of hydroxyapatite or ferrous nanoparticle/hydroxyapatite mixtures. Optical microscopy images revealed that the increased proliferation was due to enhanced cell-cell contact. The presence of magnetic Fe3O4 nanoparticles in the ceramic scaffolds significantly increased cell proliferation compared to hydroxyapatite scaffolds and tissue culture polystyrene.

[Advances in the research of application of hydrogels in three-dimensional bioprinting].

PubMed

Yang, J; Zhao, Y; Li, H H; Zhu, S H

2016-08-20

Hydrogels are three-dimensional networks made of hydrophilic polymer crosslinked through covalent bonds or physical intermolecular attractions, which can contain growth media and growth factors to support cell growth. In bioprinting, hydrogels are used to provide accurate control over cellular microenvironment and to dramatically reduce experimental repetition times, meanwhile we can obtain three-dimensional cell images of high quality. Hydrogels in three-dimensional bioprinting have received a considerable interest due to their structural similarities to the natural extracellular matrix and polyporous frameworks which can support the cellular proliferation and survival. Meanwhile, they are accompanied by many challenges.

Tea Polysaccharide Prevents Colitis-Associated Carcinogenesis in Mice by Inhibiting the Proliferation and Invasion of Tumor Cells

PubMed Central

Liu, Li-Qiao; Li, Hai-Shan; Shen, Ming-Yue; Hu, Jie-Lun; Xie, Ming-Yong

2018-01-01

The imbalance between cell proliferation and apoptosis can lead to tumor progression, causing oncogenic transformation, abnormal cell proliferation and cell apoptosis suppression. Tea polysaccharide (TPS) is the major bioactive component in green tea, it has showed antioxidant, antitumor and anti-inflammatory bioactivities. In this study, the chemoprophylaxis effects of TPS on colitis-associated colon carcinogenesis, especially the cell apoptosis activation and inhibition effects on cell proliferation and invasion were analyzed. The azoxymethane/dextran sulfate sodium (AOM/DSS) was used to induce the colorectal carcinogenesis in mice. Results showed that the tumor incidence was reduced in TPS-treated AOM/DSS mice compared to AOM/DSS mice. TUNEL staining and Ki-67 immunohistochemistry staining showed that the TPS treatment increased significantly the cell apoptosis and decreased cell proliferation among AOM/DSS mice. Furthermore, TPS reduced the expression levels of the cell cycle protein cyclin D1, matrix metalloproteinase (MMP)-2, and MMP-9. In addition, in vitro studies showed that TPS, suppressed the proliferation and invasion of the mouse colon cancer cells. Overall, our findings demonstrated that TPS could be a potential agent in the treatment and/or prevention of colon tumor, which promoted the apoptosis and suppressed the proliferation and invasion of the mouse colon cancer cells via arresting cell cycle progression. PMID:29419740

Insights in spatio-temporal characterization of human fetal neural stem cells.

PubMed

Martín-Ibáñez, Raquel; Guardia, Inés; Pardo, Mónica; Herranz, Cristina; Zietlow, Rike; Vinh, Ngoc-Nga; Rosser, Anne; Canals, Josep M

2017-05-01

Primary human fetal cells have been used in clinical trials of cell replacement therapy for the treatment of neurodegenerative disorders such as Huntington's disease (HD). However, human fetal primary cells are scarce and difficult to work with and so a renewable source of cells is sought. Human fetal neural stem cells (hfNSCs) can be generated from human fetal tissue, but little is known about the differences between hfNSCs obtained from different developmental stages and brain areas. In the present work we characterized hfNSCs, grown as neurospheres, obtained from three developmental stages: 4-5, 6-7 and 8-9weeks post conception (wpc) and four brain areas: forebrain, cortex, whole ganglionic eminence (WGE) and cerebellum. We observed that, as fetal brain development proceeds, the number of neural precursors is diminished and post-mitotic cells are increased. In turn, primary cells obtained from older embryos are more sensitive to the dissociation process, their viability is diminished and they present lower proliferation ratios compared to younger embryos. However, independently of the developmental stage of derivation proliferation ratios were very low in all cases. Improvements in the expansion rates were achieved by mechanical, instead of enzymatic, dissociation of neurospheres but not by changes in the seeding densities. Regardless of the developmental stage, neurosphere cultures presented large variability in the viability and proliferation rates during the initial 3-4 passages, but stabilized achieving significant expansion rates at passage 5 to 6. This was true also for all brain regions except cerebellar derived cultures that did not expand. Interestingly, the brain region of hfNSC derivation influences the expansion potential, being forebrain, cortex and WGE derived cells the most expandable compared to cerebellar. Short term expansion partially compromised the regional identity of cortical but not WGE cultures. Nevertheless, both expanded cultures were multipotent and kept the ability to differentiate to region specific mature neuronal phenotypes. Copyright © 2017 Elsevier Inc. All rights reserved.

In vitro evaluation of antiproliferative and cytotoxic properties of pterostilbene against human colon cancer cells.

PubMed

Wawszczyk, Joanna; Kapral, Małgorzata; Hollek, Andrzej; Węglarz, Ludmiła

2014-01-01

Colon cancer has been remaining the second leading cause of cancer mortality in Poland in the last years. Epidemiological, preclinical and clinical studies reveal that dietary phytochemicals may exert chemopreventive and therapeutic effect against colorectal cancer. There is a growing interest in identifying new biologically active agents from dietary sources in this respect. Pterostilbene (trans-3,5-dimethoxy-4-hydroxystilbene) is a naturally occurring stilbene, that has been found to have antioxidative, anti-inflammatory and antipro- liferative properties. Compared to other stilbenes, pterostilbene has greater bioavailability, and so, a greater potential for clinical applications. Recent studies showed that pterostilbene exhibits the hallmark characteristics of an anticancer agent. The aim of this study was to analyze antiproliferative and cytotoxic effects of pterostilbene on human colon cancer Caco-2 cells. They were cultured using standard techniques and exposed to increasing doses of pterostilbene (5-100 μM) for 48 and 72 h. Cell proliferation was determined by sulforhodamine B assay. The growth of treated cells was expressed as a percentage of that of untreated control cells. Pterostilbene decreased proliferation rate of Caco-2 cells in a dose- and time-dependent manner. Its concentrations = 25 μM did not affect cell growth after 48 h treatment period. Significant growth inhibition was observed in cultures incubated with higher concentrations of pterostilbene (40-100 μM). Pterostilbene at all concentrations used (5-100 μM) caused significant inhibition of cell proliferation when the experimental time period was elongated to 72 h. The maximum growth reduction was observed at 100 mM pterostilbene. The cytotoxicity of pterostilbene was evaluated in 48 h cultures based on lactate dehydrogenase (LDH) leakage into the culture medium and showed dose-related pattern. The findings of this study showed significant dose-dependent antiproliferative and cytotoxic effects of pterostilbene against human colon cancer cells in vitro.

Dynamics of cell proliferation in the adult dentate gyrus of two inbred strains of mice

NASA Technical Reports Server (NTRS)

Hayes, N. L.; Nowakowski, R. S.

2002-01-01

The output potential of proliferating populations in either the developing or the adult nervous system is critically dependent on the length of the cell cycle (T(c)) and the size of the proliferating population. We developed a new approach for analyzing the cell cycle, the 'Saturate and Survive Method' (SSM), that also reveals the dynamic behaviors in the proliferative population and estimates of the size of the proliferating population. We used this method to analyze the proliferating population of the adult dentate gyrus in 60 day old mice of two inbred strains, C57BL/6J and BALB/cByJ. The results show that the number of cells labeled by exposure to BUdR changes dramatically with time as a function of the number of proliferating cells in the population, the length of the S-phase, cell division, the length of the cell cycle, dilution of the S-phase label, and cell death. The major difference between C57BL/6J and BALB/cByJ mice is the size of the proliferating population, which differs by a factor of two; the lengths of the cell cycle and the S-phase and the probability that a newly produced cell will die within the first 10 days do not differ in these two strains. This indicates that genetic regulation of the size of the proliferating population is independent of the genetic regulation of cell death among those newly produced cells. The dynamic changes in the number of labeled cells as revealed by the SSM protocol also indicate that neither single nor repeated daily injections of BUdR accurately measure 'proliferation.'.

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

Low-Dose Radiation Induces Cell Proliferation in Human Embryonic Lung Fibroblasts but not in Lung Cancer Cells: Importance of ERK1/2 and AKT Signaling Pathways.

PubMed

Liang, Xinyue; Gu, Junlian; Yu, Dehai; Wang, Guanjun; Zhou, Lei; Zhang, Xiaoying; Zhao, Yuguang; Chen, Xiao; Zheng, Shirong; Liu, Qiang; Cai, Lu; Cui, Jiuwei; Li, Wei

2016-01-01

Hormesis and adaptive responses are 2 important biological effects of low-dose ionizing radiation (LDR). In normal tissue, LDR induces hormesis as evinced by increased cell proliferation; however, whether LDR also increases tumor cell proliferation needs to be investigated. In this study, cell proliferation was assayed by total cell numbers and the Cell Counting Kit 8 assay. Mitogen-activated protein kinases (MAPK)/extracellular signal-regulated kinase (ERK) and phosphatidylinositol 3' -kinase(PI3K)-Akt (PI3K/AKT) phosphorylation were determined by Western blot analysis. Human embryonic lung fibroblast 2BS and lung cancer NCI-H446 cell lines were irradiated with LDR at different doses (20-100 mGy). In response to 20 to 75 mGy X-rays, cell proliferation was significantly increased in 2BS but not in NCI-H446 cells. In 2BS cells, LDR at 20 to 75 mGy also stimulated phosphorylation of MAPK/ERK pathway proteins including ERK, MEK, and Raf and of the PI3K/AKT pathway protein AKT. To test whether ERK1/2 and AKT pathway activation was involved in the stimulation of cell proliferation in 2BS cells, the MAPK/ERK and PI3K/AKT pathways were inhibited using their specific inhibitors, U0126 and LY294002. U0126 decreased the phosphorylation of ERK1/2, and LY294002 decreased the phosphorylation of AKT; each could significantly inhibit LDR-induced 2BS cell proliferation. However, LDR did not stimulate these kinases, and kinase inhibitors also did not affect cell proliferation in the NCI-H446 cells. These results suggest that LDR stimulates cell proliferation via the activation of both MAPK/ERK and PI3K/AKT signaling pathways in 2BS but not in NCI-H446 cells. This finding implies the potential for applying LDR to protect normal tissues from radiotherapy without diminishing the efficacy of tumor therapy.

Low-Dose Radiation Induces Cell Proliferation in Human Embryonic Lung Fibroblasts but not in Lung Cancer Cells

PubMed Central

Liang, Xinyue; Gu, Junlian; Yu, Dehai; Wang, Guanjun; Zhou, Lei; Zhang, Xiaoying; Zhao, Yuguang; Chen, Xiao; Zheng, Shirong; Liu, Qiang; Cai, Lu

2016-01-01

Hormesis and adaptive responses are 2 important biological effects of low-dose ionizing radiation (LDR). In normal tissue, LDR induces hormesis as evinced by increased cell proliferation; however, whether LDR also increases tumor cell proliferation needs to be investigated. In this study, cell proliferation was assayed by total cell numbers and the Cell Counting Kit 8 assay. Mitogen-activated protein kinases (MAPK)/extracellular signal-regulated kinase (ERK) and phosphatidylinositol 3′ -kinase(PI3K)-Akt (PI3K/AKT) phosphorylation were determined by Western blot analysis. Human embryonic lung fibroblast 2BS and lung cancer NCI-H446 cell lines were irradiated with LDR at different doses (20-100 mGy). In response to 20 to 75 mGy X-rays, cell proliferation was significantly increased in 2BS but not in NCI-H446 cells. In 2BS cells, LDR at 20 to 75 mGy also stimulated phosphorylation of MAPK/ERK pathway proteins including ERK, MEK, and Raf and of the PI3K/AKT pathway protein AKT. To test whether ERK1/2 and AKT pathway activation was involved in the stimulation of cell proliferation in 2BS cells, the MAPK/ERK and PI3K/AKT pathways were inhibited using their specific inhibitors, U0126 and LY294002. U0126 decreased the phosphorylation of ERK1/2, and LY294002 decreased the phosphorylation of AKT; each could significantly inhibit LDR-induced 2BS cell proliferation. However, LDR did not stimulate these kinases, and kinase inhibitors also did not affect cell proliferation in the NCI-H446 cells. These results suggest that LDR stimulates cell proliferation via the activation of both MAPK/ERK and PI3K/AKT signaling pathways in 2BS but not in NCI-H446 cells. This finding implies the potential for applying LDR to protect normal tissues from radiotherapy without diminishing the efficacy of tumor therapy. PMID:26788032

Smad3 contributes to positioning of proliferating cells in colonic crypts by inducing EphB receptor protein expression

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

Furukawa, Kiyoshi; Sato, Toru; Katsuno, Tatsuro, E-mail: katsuno@faculty.chiba-u.jp

2011-02-25

Research highlights: {yields} Smad3{sup -/-} mice showed an increased number of proliferating epithelial cells in colonic crypts. {yields} Proliferating epithelial cells showed activated Wnt/{beta}-catenin pathway. {yields} Smad3{sup -/-} mice also showed intermingling of proliferating cells with differentiated cells. {yields} Loss of EphB receptor expression was observed in the colonic crypts of Smad3{sup -/-} mice. {yields} Loss of EphB receptor expression is likely responsible for cell intermingling. -- Abstract: Deficiency of Smad3, an intracellular mediator of TGF-{beta}, was shown to significantly accelerate re-epithelialization of the colonic mucosa. This study was performed to investigate the molecular mechanisms by which Smad3 controls colonicmore » epithelial cell proliferation and crypt formation. Smad3{sup ex8/ex8} C57BL/6 mice were used in this study and wild-type littermates served as controls. The number of proliferating cells in the isolated colonic epithelium of Smad3{sup -/-} mice was significantly increased compared to that in wild-type littermates. Protein levels of the cell cycle inhibitors p21 and p27 were significantly decreased, while that of c-Myc was increased in the isolated colonic epithelium from Smad3{sup -/-} mice. In the colonic tissue of wild-type mice, cell proliferation was restricted to the bottom of the crypts in accordance with nuclear {beta}-catenin staining, whereas proliferating cells were located throughout the crypts in Smad3{sup -/-} mice in accordance with nuclear {beta}-catenin staining, suggesting that Smad3 is essential for locating proliferating cells at the bottom of the colonic crypts. Notably, in Smad3{sup -/-} mice, there was loss of EphB2 and EphB3 receptor protein expression, critical regulators of proliferating cell positioning, while EphB receptor protein expression was confirmed at the bottom of the colonic crypts in wild-type mice. These observations indicated that disturbance of the EphB/ephrin B system brings about mispositioning of proliferating cells in the colonic crypts of Smad3{sup -/-} mice. In conclusion, Smad3 is essential for controlling number and positioning of proliferating cells in the colonic crypts and contributes to formation of a 'proliferative zone' at the bottom of colonic crypts in the normal colon.« less

Cytoglobin inhibits migration through PI3K/AKT/mTOR pathway in fibroblast cells.

PubMed

Demirci, Selami; Doğan, Ayşegül; Apdik, Hüseyin; Tuysuz, Emre Can; Gulluoglu, Sukru; Bayrak, Omer Faruk; Şahin, Fikrettin

2018-01-01

Cell proliferation and migration are crucial in many physiological processes including development, cancer, tissue repair, and wound healing. Cell migration is regulated by several signaling molecules. Identification of genes related to cell migration is required to understand molecular mechanism of non-healing chronic wounds which is a major concern in clinics. In the current study, the role of cytoglobin (CYGB) gene in fıbroblast cell migration and proliferation was described. L929 mouse fibroblast cells were transduced with lentiviral particles for CYGB and GFP, and analyzed for cell proliferation and migration ability. Fibroblast cells overexpressing CYGB displayed decreased cell proliferation, colony formation capacity, and cell migration. Phosphorylation levels of mTOR and two downstream effectors S6 and 4E-BP1 which take part in PI3K/AKT/mTOR signaling declined in CYGB-overexpressing cells. Microarray analysis indicated that CYGB overexpression leads to downregulation of cell proliferation, migration, and tumor growth associated genes in L929 cell line. This study demonstrated the role of CYGB in fibroblast cell motility and proliferation. CYGB could be a promising candidate for further studies as a potential target for diseases related to cell migration such as cancer and chronic wound treatment.

Involvement of prolyl isomerase PIN1 in the cell cycle progression and proliferation of hepatic oval cells.

PubMed

Risal, Prabodh; Shrestha, Nirajan; Chand, Lokendra; Sylvester, Karl G; Jeong, Yeon Jun

2017-04-01

Liver regenerates remarkably after toxic injury or surgical resection. In the case of failure of resident hepatocytes to restore loss, repopulation is carried out by induction, proliferation, and differentiation of the progenitor cell. Although, some signaling pathways have been verified to contribute oval cell-mediated liver regeneration, role of Peptidyl-prolyl cis-trans isomerase NIMA-interacting 1(Pin1) in the oval cells proliferation is unknown. In the present study, we evaluate the role of Pin1 in oval cells proliferation. In our study, the expression of Pin1 in the mice liver increased after three weeks feeding of 3, 5-diethoxycarbonyl-1, 4-dihydrocollidine (DDC) diet along with the proliferation of oval cells. The expression of Pin1 was higher in oval cells compared to the hepatocytes.Pin1 inhibition by Juglone reduced oval cell proliferation, which was restored to normal when oval cells were treated with IGF-1. Consistent with increased cell growth, expression of Pin1, β-catenin and PCNA were increased in IGF-1 treated cells in a time dependent manner. In FACS analysis, siRNA-mediated knockdown of the Pin1 protein in the oval cells significantly increased the numbers of cells in G0/G1 phase. Furthermore, hepatocyte when treated with TGF-β showed marked reduction in cell proliferation and expression of Pin1 whereas this effect was not seen in the oval cells treated with TGF-β. In conclusion, Pin1 plays important role in the cell cycle progression and increase oval cells proliferation which may be crucial in chronic liver injury. Copyright © 2017 Elsevier GmbH. All rights reserved.

Dual effect of LPS on murine myeloid leukemia cells: Pro-proliferation and anti-proliferation

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

Yu, Lingling; Noncoding RNA Center, Yangzhou University, Yangzhou 225001; Zhao, Yingmin

Modification of the bone marrow microenvironment is considered as a promising strategy to control leukemic cell proliferation, diseases progression and relapse after treatment. However, due to the diversity and complexity of the cellular and molecular compartments in the leukemic microenvironment, it is extremely difficult to dissect the role of each individual molecule or cell type in vivo. Here we established an in vitro system to dissect the role of lipopolysaccharide (LPS), stromal cells and endothelial cells in the growth of mouse myeloid tumor cells and B-lymphoma cells. We found that either LPS or bone marrow stromal cells as a feedermore » layer in culture is required for the proliferation of myeloid tumor cells. Surprisingly, the growth of myeloid leukemic cells on stromal cells is strongly inhibited when coupled with LPS in culture. This opposing effect of LPS, a complete switch from pro-proliferation to antitumor growth is due, at least in part, to the rapidly increased production of interleukin 12, Fas ligand and tissue inhibitor of metalloproteinases-2 from stromal cells stimulated by LPS. These results demonstrate that LPS can either facilitate or attenuate tumor cell proliferation, thus changing the disease course of myeloid leukemias through its direct effect or modulation of the tumor microenvironment. - Highlights: • LPS alone in culture is required for the proliferation of murine myeloid tumor cells. • Bone marrow stromal cells as a feeder layer is also required for the proliferation of myeloid tumor cells. • However, the growth of myeloid tumor cells is inhibited when LPS and stromal cells are both available in culture. • Thus LPS can either facilitate or attenuate tumor growth through its direct effect or modulation of tumor microenvironment.« less

The MADS-box XAANTAL1 increases proliferation at the Arabidopsis root stem-cell niche and participates in transition to differentiation by regulating cell-cycle components

PubMed Central

García-Cruz, Karla V.; García-Ponce, Berenice; Garay-Arroyo, Adriana; Sanchez, María De La Paz; Ugartechea-Chirino, Yamel; Desvoyes, Bénédicte; Pacheco-Escobedo, Mario A.; Tapia-López, Rosalinda; Ransom-Rodríguez, Ivan; Gutierrez, Crisanto; Alvarez-Buylla, Elena R.

2016-01-01

Background Morphogenesis depends on the concerted modulation of cell proliferation and differentiation. Such modulation is dynamically adjusted in response to various external and internal signals via complex transcriptional regulatory networks that mediate between such signals and regulation of cell-cycle and cellular responses (proliferation, growth, differentiation). In plants, which are sessile, the proliferation/differentiation balance is plastically adjusted during their life cycle and transcriptional networks are important in this process. MADS-box genes are key developmental regulators in eukaryotes, but their role in cell proliferation and differentiation modulation in plants remains poorly studied. Methods We characterize the XAL1 loss-of-function xal1-2 allele and overexpression lines using quantitative cellular and cytometry analyses to explore its role in cell cycle, proliferation, stem-cell patterning and transition to differentiation. We used quantitative PCR and cellular markers to explore if XAL1 regulates cell-cycle components and PLETHORA1 (PLT1) gene expression, as well as confocal microscopy to analyse stem-cell niche organization. Key Results We previously showed that XAANTAL1 (XAL1/AGL12) is necessary for Arabidopsis root development as a promoter of cell proliferation in the root apical meristem. Here, we demonstrate that XAL1 positively regulates the expression of PLT1 and important components of the cell cycle: CYCD3;1, CYCA2;3, CYCB1;1, CDKB1;1 and CDT1a. In addition, we show that xal1-2 mutant plants have a premature transition to differentiation with root hairs appearing closer to the root tip, while endoreplication in these plants is partially compromised. Coincidently, the final size of cortex cells in the mutant is shorter than wild-type cells. Finally, XAL1 overexpression-lines corroborate that this transcription factor is able to promote cell proliferation at the stem-cell niche. Conclusion XAL1 seems to be an important component of the networks that modulate cell proliferation/differentiation transition and stem-cell proliferation during Arabidopsis root development; it also regulates several cell-cycle components. PMID:27474508

Effects of High-Temperature-Pressure Polymerized Resin-Infiltrated Ceramic Networks on Oral Stem Cells

PubMed Central

Nassif, Ali; Berbar, Tsouria; Le Goff, Stéphane; Berdal, Ariane; Sadoun, Michael; Fournier, Benjamin P. J.

2016-01-01

Objectives The development of CAD—CAM techniques called for new materials suited to this technique and offering a safe and sustainable clinical implementation. The infiltration of resin in a ceramic network under high pressure and high temperature defines a new class of hybrid materials, namely polymer infiltrated ceramics network (PICN), for this purpose which requires to be evaluated biologically. We used oral stem cells (gingival and pulpal) as an in vitro experimental model. Methods Four biomaterials were grinded, immersed in a culture medium and deposed on stem cells from dental pulp (DPSC) and gingiva (GSC): Enamic (VITA®), Experimental Hybrid Material (EHM), EHM with initiator (EHMi) and polymerized Z100™ composite material (3M®). After 7 days of incubation; viability, apoptosis, proliferation, cytoskeleton, inflammatory response and morphology were evaluated in vitro. Results Proliferation was insignificantly delayed by all the tested materials. Significant cytotoxicity was observed in presence of resin based composites (MTT assay), however no detectable apoptosis and some dead cells were detected like in PICN materials. Cell morphology, major cytoskeleton and extracellular matrix components were not altered. An intimate contact appeared between the materials and cells. Clinical Significance The three new tested biomaterials did not exhibit adverse effects on oral stem cells in our experimental conditions and may be an interesting alternative to ceramics or composite based CAD—CAM blocks. PMID:27196425

Why the dish makes a difference: quantitative comparison of polystyrene culture surfaces.

PubMed

Zeiger, Adam S; Hinton, Benjamin; Van Vliet, Krystyn J

2013-07-01

There is wide anecdotal recognition that biological cell viability and behavior can vary significantly as a function of the source of commercial tissue culture polystyrene (TCPS) culture vessels to which those cells adhere. However, this marked material dependency is typically resolved by selecting and then consistently using the same manufacturer's product - following protocol - rather than by investigating the material properties that may be responsible for such experimental variation. Here, we quantified several physical properties of TCPS surfaces obtained from a wide range of commercial sources and processing steps, through the use of atomic force microscopy (AFM)-based imaging and analysis, goniometry and protein adsorption quantification. We identify qualitative differences in surface features, as well as quantitative differences in surface roughness and wettability that cannot be attributed solely to differences in surface chemistry. We also find significant differences in cell morphology and proliferation among cells cultured on different TCPS surfaces, and resolve a correlation between nanoscale surface roughness and cell proliferation rate for both cell types considered. Interestingly, AFM images of living adherent cells on these nanotextured surfaces demonstrate direct interactions between cellular protrusions and topographically distinct features. These results illustrate and quantify the significant differences in material surface properties among these ubiquitous materials, allowing us to better understand why the dish can make a difference in biological experiments. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Comparative study of antitumor effects of bromelain and papain in human cholangiocarcinoma cell lines.

PubMed

Müller, Alena; Barat, Samarpita; Chen, Xi; Bui, Khac Cuong; Bozko, Przemyslaw; Malek, Nisar P; Plentz, Ruben R

2016-05-01

Cholangiocarcinoma (CC) worldwide is the most common biliary malignancy with poor prognostic value and new systemic treatments are desirable. Plant extracts like bromelain and papain, which are cysteine proteases from the fruit pineapple and papaya, are known to have antitumor activities. Therefore, in this study for the first time we investigated the anticancer effect of bromelain and papain in intra- and extrahepatic human CC cell lines. The effect of bromelain and papain on human CC cell growth, migration, invasion and epithelial plasticity was analyzed using cell proliferation, wound healing, invasion and apoptosis assay, as well as western blotting. Bromelain and papain lead to a decrease in the proliferation, invasion and migration of CC cells. Both plant extracts inhibited NFκB/AMPK signalling as well as their downstream signalling proteins such as p-AKT, p-ERK, p-Stat3. Additionally, MMP9 and other epithelial-mesenchymal-transition markers were partially found to be downregulated. Apoptosis was induced after bromelain and papain treatment. Interestingly, bromelain showed an overall more effective inhibition of CC as compared to papain. siRNA mediated silencing of NFκB on CC cells indicated that bromelain and papain have cytotoxic effects on human CC cell lines and bromelain and partially papain in comparison impair tumor growth by NFκB/AMPK signalling. Especially bromelain can evolve as promising, potential therapeutic option that might open new insights for the treatment of human CC.