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Sample records for aberrant cell proliferation

  1. Aberrant activation of M phase proteins by cell proliferation-evoking carcinogens after 28-day administration in rats.

    PubMed

    Yafune, Atsunori; Taniai, Eriko; Morita, Reiko; Hayashi, Hitomi; Suzuki, Kazuhiko; Mitsumori, Kunitoshi; Shibutani, Makoto

    2013-06-07

    We have previously reported that hepatocarcinogens increase liver cells expressing p21(Cip1), a G1 checkpoint protein and M phase proteins after 28-day treatment in rats. This study aimed to identify early prediction markers of carcinogens available in many target organs after 28-day treatment in rats. Immunohistochemical analysis was performed on Ki-67, p21(Cip1) and M phase proteins [nuclear Cdc2, phospho-Histone H3 (p-Histone H3), Aurora B and heterochromatin protein 1α (HP1α)] with carcinogens targeting different organs. Carcinogens targeting thyroid (sulfadimethoxine; SDM), urinary bladder (phenylethyl isothiocyanate), forestomach (butylated hydroxyanisole; BHA), glandular stomach (catechol; CC), and colon (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine and chenodeoxycholic acid) were examined using a non-carcinogenic toxicant (caprolactam) and carcinogens targeting other organs as negative controls. All carcinogens increased Ki-67(+), nuclear Cdc2(+), p-Histone H3(+) or Aurora B(+) carcinogenic target cells, except for both colon carcinogens, which did not increase cell proliferation. On the other hand, p21(Cip1+) cells increased with SDM and CC. HP1α responded only to BHA. Results revealed carcinogens evoking cell proliferation concurrently induced cell cycle arrest at M phase or showing chromosomal instability reflecting aberration in cell cycle regulation, irrespective of target organs, after 28-day treatment. Therefore, M phase proteins may be early prediction markers of carcinogens evoking cell proliferation in many target organs. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  2. Increase of poorly proliferated p63+ /Ki67+ basal cells forming multiple layers in the aberrant remodeled epithelium in nasal polyps.

    PubMed

    Zhao, L; Li, Y Y; Li, C W; Chao, S S; Liu, J; Nam, H N; Dung, N T N; Shi, L; Wang, D Y

    2017-06-01

    Aberrant epithelial remodeling with the ectopic expression of p63 (basal cell markers) is an important pathologic phenomenon seen in chronically inflamed airway epithelium such as in nasal polyps (NPs). Biopsies were obtained from 55 NP patients and 18 healthy controls (inferior turbinate). Among NP patients, 15 were treated with oral and nasal steroids, so that two sets of NP biopsies were taken before and after the treatments. p63, Ki67, type IV β-tubulin, and cell cycle markers were investigated in these specimens. The number of p63 + cells is significantly higher in both hyperplastic (1.53-fold, P < 0.0001) and squamous metaplastic (2.02-fold, P < 0.0001) epithelium from NPs than from healthy controls. There are three types of proliferative basal cells (p63 + /Ki67 + ) which are in different phases of the cell cycle, such as G1 phase (type I cells), S to G2 phase (type II cells), and mitosis (type III cells). Of importance, some type I cells may arrest after proliferation although they may still be p63 + /Ki67 + . In healthy epithelium, the ratio of the type I and II cells is almost 50:50. However, less type II cells are found in hyperplastic epithelium (34.85%, P = 0.012) and in squamous metaplastic epithelium (30.77%, P = 0.02) together with the presence of type III cells (3.45%, P = 0.01). These findings were not changed after steroid treatments. An increase of poorly proliferated basal cells forming multiple layers, which may stain for basal cell markers but does not form a proper epidermal barrier, is an important histopathologic phenomenon in aberrant remodeled epithelium of NPs. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Aberrant activation of ubiquitin D at G2 phase and apoptosis by carcinogens that evoke cell proliferation after 28-day administration in rats.

    PubMed

    Taniai, Eriko; Yafune, Atsunori; Hayashi, Hitomi; Itahashi, Megu; Hara-Kudo, Yukiko; Suzuki, Kazuhiko; Mitsumori, Kunitoshi; Shibutani, Makoto

    2012-01-01

    We have previously reported that renal carcinogens examined in rats increase tubular cell proliferation and topoisomerase (Topo) IIα(+) cells. The present study was aimed at identifying early prediction markers of carcinogens after 28-day treatment in rats. Following gene expression screening by microarrays in renal tubules with renal carcinogens, immunohistochemical analysis and TUNEL-assay were performed with carcinogens targeting different organs. All renal carcinogens tested (ferric nitrilotriacetic acid, ochratoxin A (OTA), monuron, tris(2-chloroethyl) phosphate, and potassium bromate) increased tubular cells immunoreactive for minichromosome maintenance 3 (Mcm3) or ubiquitin D (Ubd) or those showing apoptosis, compared with untreated controls or non-carcinogenic renal toxicants. Carcinogens targeting the liver (thioacetamide (TAA), fenbendazole, piperonyl butoxide (PBO) and methyleugenol), thyroid (sulfadimethoxine), urinary bladder (phenylethyl isothiocyanate), forestomach (butylated hydroxyanisole), glandular stomach (catechol), and colon (chenodeoxycholic acid and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine) were examined for induction of Mcm3, Ubd, Topo IIα, Ki-67 and apoptosis using non-carcinogenic toxicants as negative controls. All carcinogens increased Mcm3(+), Ubd(+), Topo IIα(+), Ki-67(+) or TUNEL(+) cells, except for hepatocarcinogen PBO and both colon carcinogens, which did not increase cell proliferation. Ubd(+) cells co-expressing Topo IIα was increased without changing phospho-Histone H3-co-expressing cell population as examined with OTA and TAA. Results revealed cooperative responses of Topo IIα, Ubd and apoptosis by carcinogens inducing high proliferation activity, irrespective of target organs, examined here after a 28-day administration. Aberrant expression of Ubd at G(2) phase and increased apoptosis reflecting aberrant cell cycle regulation may be the common feature of these carcinogens.

  4. Silibinin inhibits aberrant lipid metabolism, proliferation and emergence of androgen-independence in prostate cancer cells via primarily targeting the sterol response element binding protein 1

    PubMed Central

    Nambiar, Dhanya K.; Deep, Gagan; Singh, Rana P.; Agarwal, Chapla; Agarwal, Rajesh

    2014-01-01

    Prostate cancer (PCA) kills thousands of men every year, demanding additional approaches to better understand and target this malignancy. Recently, critical role of aberrant lipogenesis is highlighted in prostate carcinogenesis, offering a unique opportunity to target it to reduce PCA. Here, we evaluated efficacy and associated mechanisms of silibinin in inhibiting lipid metabolism in PCA cells. At physiologically achievable levels in human, silibinin strongly reduced lipid and cholesterol accumulation specifically in human PCA cells but not in non-neoplastic prostate epithelial PWR-1E cells. Silibinin also decreased nuclear protein levels of sterol regulatory element binding protein 1 and 2 (SREBP1/2) and their target genes only in PCA cells. Mechanistically, silibinin activated AMPK, thereby increasing SREBP1 phosphorylation and inhibiting its nuclear translocation; AMPK inhibition reversed silibinin-mediated decrease in nuclear SREBP1 and lipid accumulation. Additionally, specific SREBP inhibitor fatostatin and stable overexpression of SREBP1 further confirmed the central role of SREBP1 in silibinin-mediated inhibition of PCA cell proliferation and lipid accumulation and cell cycle arrest. Importantly, silibinin also inhibited synthetic androgen R1881-induced lipid accumulation and completely abrogated the development of androgen-independent LNCaP cell clones via targeting SREBP1/2. Together, these mechanistic studies suggest that silibinin would be effective against PCA by targeting critical aberrant lipogenesis. PMID:25294820

  5. Silibinin inhibits aberrant lipid metabolism, proliferation and emergence of androgen-independence in prostate cancer cells via primarily targeting the sterol response element binding protein 1.

    PubMed

    Nambiar, Dhanya K; Deep, Gagan; Singh, Rana P; Agarwal, Chapla; Agarwal, Rajesh

    2014-10-30

    Prostate cancer (PCA) kills thousands of men every year, demanding additional approaches to better understand and target this malignancy. Recently, critical role of aberrant lipogenesis is highlighted in prostate carcinogenesis, offering a unique opportunity to target it to reduce PCA. Here, we evaluated efficacy and associated mechanisms of silibinin in inhibiting lipid metabolism in PCA cells. At physiologically achievable levels in human, silibinin strongly reduced lipid and cholesterol accumulation specifically in human PCA cells but not in non-neoplastic prostate epithelial PWR-1E cells. Silibinin also decreased nuclear protein levels of sterol regulatory element binding protein 1 and 2 (SREBP1/2) and their target genes only in PCA cells. Mechanistically, silibinin activated AMPK, thereby increasing SREBP1 phosphorylation and inhibiting its nuclear translocation; AMPK inhibition reversed silibinin-mediated decrease in nuclear SREBP1 and lipid accumulation. Additionally, specific SREBP inhibitor fatostatin and stable overexpression of SREBP1 further confirmed the central role of SREBP1 in silibinin-mediated inhibition of PCA cell proliferation and lipid accumulation and cell cycle arrest. Importantly, silibinin also inhibited synthetic androgen R1881-induced lipid accumulation and completely abrogated the development of androgen-independent LNCaP cell clones via targeting SREBP1/2. Together, these mechanistic studies suggest that silibinin would be effective against PCA by targeting critical aberrant lipogenesis.

  6. Cell Proliferation on Planar and Curved Substrates

    NASA Astrophysics Data System (ADS)

    Gaines, Michelle; Chang, Ya Wen; Cruz, Ricardo; Fragkopoulos, Alexandros; Garcia, Andres; Fernandez-Nieves, Alberto

    Aberrant epithelial collective cell growth is one of the major challenges to be addressed in order to treat diseases such as cancer and organ fibrosis. The conditions of the extracellular microenvironment, properties of the cells' cytoskeleton, and interfacial properties of the substratum (the surface in contact with epithelial cells) have a significant influence on the migratory behavior of epithelial cells, cell proliferation and migration. This work focuses on understanding the impact the substratum curvature has on cell behavior. We focus on cell proliferation first and study MDCK cells on both planar and curved hydrogel substrates. The curved hydrogels are based on polyacrylamide and have toroidal shape, with tube radius 200 um and an aspect ratio in the rage between 2 and 9. Proliferation is measured using the Click-it EDU assay (Invitrogen), which measures cells that are synthesizing DNA. Funding Source is Childrens Healthcare of Atlanta.

  7. Cell Proliferation in Neuroblastoma

    PubMed Central

    Stafman, Laura L.; Beierle, Elizabeth A.

    2016-01-01

    Neuroblastoma, the most common extracranial solid tumor of childhood, continues to carry a dismal prognosis for children diagnosed with advanced stage or relapsed disease. This review focuses upon factors responsible for cell proliferation in neuroblastoma including transcription factors, kinases, and regulators of the cell cycle. Novel therapeutic strategies directed toward these targets in neuroblastoma are discussed. PMID:26771642

  8. Probiotic Dahi containing Lactobacillus acidophilus and Bifidobacterium bifidum modulates the formation of aberrant crypt foci, mucin-depleted foci, and cell proliferation on 1,2-dimethylhydrazine-induced colorectal carcinogenesis in Wistar rats.

    PubMed

    Mohania, Dheeraj; Kansal, Vinod K; Kruzliak, Peter; Kumari, Archana

    2014-08-01

    Aberrant crypt foci (ACF) and mucin-depleted foci (MDF) are pre-neoplastic lesions identified in the colon of carcinogen-treated rodents and in humans at high risk for colon cancer. The present study was carried out to divulge the protective potential of the probiotic Dahi containing Lactobacillus acidophilus LaVK2 and Bifidobacterium bifidum BbVK3 alone or in combination with piroxicam (PXC) on the development of early biomarkers of colorectal carcinogenesis in male Wistar rats administered 1,2-dimethylhydrazine (DMH). DMH was injected subcutaneously at the rate of 40 mg/kg body weight per animal twice a week for 2 weeks. A total of 120 male Wistar rats were randomly allocated to five groups, each group having 24 animals. The rats were fed with buffalo milk or probiotic supplement (20 grams) alone or as an adjunct with PXC in addition to a basal diet ad libitum for 32 weeks. Group I was offered buffalo milk (BM) and served as the control group. Group II was administered DMH along with BM and served as the DMH-control group; group III was administered BM-DMH-PXC, in which besides administering BM-DMH, PXC was also offered. Group IV was offered probiotic LaBb Dahi and DMH, and group V was offered both probiotic LaBb Dahi and PXC along with DMH. The rats were euthanized at the 8(th), 16(th), and 32(nd) week of the experiment and examined for development of ACF, aberrant crypts per ACF (AC/ACF), mucin-depleted foci (MDF), large MDF, and proliferating cell nuclear antigen (PCNA) labeling index. Administration of DMH in rats induced pre-neoplastic lesions (ACF and MDF) and increased the PCNA index in colorectal tissue. A significant (p<0.05) reduction in the number of ACF, AC/ACF, MDF, large MDF, and PCNA labeling index were observed in the probiotic LaBb Dahi group compared with the DMH control group. Feeding rats with LaBb Dahi or treatment with PXC diminished the initiation and progression of DMH-induced pre-neoplastic lesions and the PCNA index, and treatment with

  9. Aberrant phenotypes in peripheral T cell lymphomas.

    PubMed Central

    Hastrup, N; Ralfkiaer, E; Pallesen, G

    1989-01-01

    Seventy six peripheral T cell lymphomas were examined immunohistologically to test their reactivity with a panel of monoclonal antibodies against 11 T cell associated antigens (CD1-8, CD27, UCHL1, and the T cell antigen receptor). Sixty two (82%) lymphomas showed aberrant phenotypes, and four main categories were distinguished as follows: (i) lack of one or several pan-T cell antigens (49, 64% of the cases); (ii) loss of both the CD4 and CD8 antigens (11, 15% of the cases); (iii) coexpression of the CD4 and CD8 antigens (13, 17% of the cases); and (iv) expression of the CD1 antigen (eight, 11% of the cases). No correlation was seen between the occurrence of aberrant phenotypes and the histological subtype. It is concluded that the demonstration of an aberrant phenotype is a valuable supplement to histological assessment in the diagnosis of peripheral T cell lymphomas. It is recommended that the panel of monoclonal antibodies against T cell differentiation antigens should be fairly large, as apparently any antigen may be lost in the process of malignant transformation. Images Figure PMID:2469701

  10. Label Structured Cell Proliferation Models

    DTIC Science & Technology

    2010-06-16

    and (, + ) are the cell proliferation and death rates , respectively, relative to the moving label coordinate system + . Daughter...proliferation and death rates relative to this new coordinate system. While not common in the biological sciences, it is altogether common in the physical

  11. Calcium signaling and cell proliferation.

    PubMed

    Pinto, Mauro Cunha Xavier; Kihara, Alexandre Hiroaki; Goulart, Vânia A M; Tonelli, Fernanda M P; Gomes, Katia N; Ulrich, Henning; Resende, Rodrigo R

    2015-11-01

    Cell proliferation is orchestrated through diverse proteins related to calcium (Ca(2+)) signaling inside the cell. Cellular Ca(2+) influx that occurs first by various mechanisms at the plasma membrane, is then followed by absorption of Ca(2+) ions by mitochondria and endoplasmic reticulum, and, finally, there is a connection of calcium stores to the nucleus. Experimental evidence indicates that the fluctuation of Ca(2+) from the endoplasmic reticulum provides a pivotal and physiological role for cell proliferation. Ca(2+) depletion in the endoplasmatic reticulum triggers Ca(2+) influx across the plasma membrane in an phenomenon called store-operated calcium entries (SOCEs). SOCE is activated through a complex interplay between a Ca(2+) sensor, denominated STIM, localized in the endoplasmic reticulum and a Ca(2+) channel at the cell membrane, denominated Orai. The interplay between STIM and Orai proteins with cell membrane receptors and their role in cell proliferation is discussed in this review. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Structural centrosome aberrations promote non-cell-autonomous invasiveness.

    PubMed

    Ganier, Olivier; Schnerch, Dominik; Oertle, Philipp; Lim, Roderick Yh; Plodinec, Marija; Nigg, Erich A

    2018-05-02

    Centrosomes are the main microtubule-organizing centers of animal cells. Although centrosome aberrations are common in tumors, their consequences remain subject to debate. Here, we studied the impact of structural centrosome aberrations, induced by deregulated expression of ninein-like protein (NLP), on epithelial spheres grown in Matrigel matrices. We demonstrate that NLP-induced structural centrosome aberrations trigger the escape ("budding") of living cells from epithelia. Remarkably, all cells disseminating into the matrix were undergoing mitosis. This invasive behavior reflects a novel mechanism that depends on the acquisition of two distinct properties. First, NLP-induced centrosome aberrations trigger a re-organization of the cytoskeleton, which stabilizes microtubules and weakens E-cadherin junctions during mitosis. Second, atomic force microscopy reveals that cells harboring these centrosome aberrations display increased stiffness. As a consequence, mitotic cells are pushed out of mosaic epithelia, particularly if they lack centrosome aberrations. We conclude that centrosome aberrations can trigger cell dissemination through a novel, non-cell-autonomous mechanism, raising the prospect that centrosome aberrations contribute to the dissemination of metastatic cells harboring normal centrosomes. © 2018 The Authors. Published under the terms of the CC BY NC ND 4.0 license.

  13. Structural centrosome aberrations sensitize polarized epithelia to basal cell extrusion.

    PubMed

    Ganier, Olivier; Schnerch, Dominik; Nigg, Erich A

    2018-06-01

    Centrosome aberrations disrupt tissue architecture and may confer invasive properties to cancer cells. Here we show that structural centrosome aberrations, induced by overexpression of either Ninein-like protein (NLP) or CEP131/AZI1, sensitize polarized mammalian epithelia to basal cell extrusion. While unperturbed epithelia typically dispose of damaged cells through apical dissemination into luminal cavities, certain oncogenic mutations cause a switch in directionality towards basal cell extrusion, raising the potential for metastatic cell dissemination. Here we report that NLP-induced centrosome aberrations trigger the preferential extrusion of damaged cells towards the basal surface of epithelial monolayers. This switch in directionality from apical to basal dissemination coincides with a profound reorganization of the microtubule cytoskeleton, which in turn prevents the contractile ring repositioning that is required to support extrusion towards the apical surface. While the basal extrusion of cells harbouring NLP-induced centrosome aberrations requires exogenously induced cell damage, structural centrosome aberrations induced by excess CEP131 trigger the spontaneous dissemination of dying cells towards the basal surface from MDCK cysts. Thus, similar to oncogenic mutations, structural centrosome aberrations can favour basal extrusion of damaged cells from polarized epithelia. Assuming that additional mutations may promote cell survival, this process could sensitize epithelia to disseminate potentially metastatic cells. © 2018 The Authors.

  14. Structural centrosome aberrations favor proliferation by abrogating microtubule-dependent tissue integrity of breast epithelial mammospheres

    PubMed Central

    Schnerch, D; Nigg, E A

    2016-01-01

    Structural centrosome aberrations are frequently observed in early stage carcinomas, but their role in malignant transformation is poorly understood. Here, we examined the impact of overexpression of Ninein-like protein (Nlp) on the architecture of polarized epithelia in three-dimensional mammospheres. When Nlp was overexpressed to levels resembling those seen in human tumors, it formed striking centrosome-related bodies (CRBs), which sequestered Ninein and affected the kinetics of microtubule (MT) nucleation and release. In turn, the profound reorganization of the MT cytoskeleton resulted in mislocalization of several adhesion and junction proteins as well as the tumor suppressor Scribble, resulting in the disruption of epithelial polarity, cell-cell interactions and mammosphere architecture. Remarkably, cells harboring Nlp-CRBs displayed an enhanced proliferative response to epidermal growth factor. These results demonstrate that structural centrosome aberrations cause not only the disruption of epithelial polarity but also favor overproliferation, two phenotypes typically associated with human carcinomas. PMID:26364601

  15. Aberrant DNA Methylation in Chronic Myeloid Leukemia: Cell Fate Control, Prognosis, and Therapeutic Response.

    PubMed

    Behzad, Masumeh Maleki; Shahrabi, Saeid; Jaseb, Kaveh; Bertacchini, Jessika; Ketabchi, Neda; Saki, Najmaldin

    2018-01-31

    Chronic myeloid leukemia (CML) is a hematopoietic stem cell malignancy characterized by the expression of the BCR-ABL1 fusion gene with different chimeric transcripts. Despite the crucial impact of constitutively active tyrosine kinase in CML pathogenesis, aberrant DNA methylation of certain genes plays an important role in disease progression and the development of drug resistance. This article reviews recent findings relevant to the effect of DNA methylation pattern of regulatory genes on various cellular activities such as cell proliferation and survival, as well as cell-signaling molecules in CML. These data might contribute to defining the role of aberrant DNA methylation in disease initiation and progression. However, further studies are needed on the validation of specific aberrant methylation markers regarding the prognosis and prediction of response among the CML patients.

  16. 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.

  17. Cell proliferation assessment in oncology.

    PubMed

    Hofstädter, F; Knüchel, R; Rüschoff, J

    1995-01-01

    A review of the current knowledge on cell cycle control and the techniques used to assess proliferation of normal and neoplastic cells was the focus of a workshop in Regensburg, Germany, held under the joint auspices of the Graduiertenkolleg: Therapieforschung Onkologie and the Committee on AgNOR Quantification. An overview of the recently discovered group of cyclins and their specific kinases, and of other proliferation-associated antigens, such as Ki67, PCNA and topoiseromase II alpha, was given. The topics continued with a reappraisal of modern imaging and flow-cytometric techniques. An update of the relation of AgNORs to cellular proliferation and differentiation was the link to presentations on clinical data, problems and strategies for standardization, as well as guidelines to establish the prognostic value of marker molecules. These lectures were supported by posters. Bringing together researchers from life sciences, technically oriented workers, pathologists, and clinicians resulted in a lively and constructive discussion, which is briefly summarized in the Concluding remarks.

  18. Cell proliferation in normal epidermis

    SciTech Connect

    Weinstein, G.D.; McCullough, J.L.; Ross, P.

    1984-06-01

    A detailed examination of cell proliferation kinetics in normal human epidermis is presented. Using tritiated thymidine with autoradiographic techniques, proliferative and differentiated cell kinetics are defined and interrelated. The proliferative compartment of normal epidermis has a cell cycle duration (Tc) of 311 h derived from 3 components: the germinative labeling index (LI), the duration of DNA synthesis (ts), and the growth fraction (GF). The germinative LI is 2.7% +/- 1.2 and ts is 14 h, the latter obtained from a composite fraction of labeled mitoses curve obtained from 11 normal subjects. The GF obtained from the literature and from humanmore » skin xenografts to nude mice is estimated to be 60%. Normal-appearing epidermis from patients with psoriasis appears to have a higher proliferation rate. The mean LI is 4.2% +/- 0.9, approximately 50% greater than in normal epidermis. Absolute cell kinetic values for this tissue, however, cannot yet be calculated for lack of other information on ts and GF. A kinetic model for epidermal cell renewal in normal epidermis is described that interrelates the rate of birth/entry, transit, and/or loss of keratinocytes in the 3 epidermal compartments: proliferative, viable differentiated (stratum malpighii), and stratum corneum. Expected kinetic homeostasis in the epidermis is confirmed by the very similar ''turnover'' rates in each of the compartments that are, respectively, 1246, 1417, and 1490 cells/day/mm2 surface area. The mean epidermal turnover time of the entire tissue is 39 days. The Tc of 311 h in normal cells in 8-fold longer than the psoriatic Tc of 36 h and is necessary for understanding the hyperproliferative pathophysiologic process in psoriasis.« less

  19. Induction of chromosome aberrations in human cells by charged particles

    NASA Technical Reports Server (NTRS)

    Wu, H.; Durante, M.; George, K.; Yang, T. C.

    1997-01-01

    Chromosome aberrations induced by high-energy charged particles in normal human lymphocytes and human fibroblasts have been investigated. The charged particles included 250 MeV/nucleon protons, 290 MeV/nucleon carbon ions and 1 GeV/nucleon iron ions. The energies of the charged particles were higher than in most of the studies reported in the literature. Lymphocytes were stimulated to grow immediately after irradiation, while fibroblasts were incubated at 37 degrees C for 24 h for repair. Chromosomes were collected at the first mitosis after irradiation and chromosome aberrations were scored using the fluorescence in situ hybridization (FISH) technique with a whole-chromosome 4 probe. Chromosome aberrations were classified as reciprocal exchanges, incomplete exchanges, deletions and complex exchanges. The relative biological effectiveness (RBE) for each type of aberration was calculated by dividing a dose of 4 Gy by the dose of the charged particles producing the same effect as 4 Gy of gamma rays. Results of this study showed that complex aberrations have the highest RBE for radiation of high linear energy transfer (LET) for human lymphocytes, but for fibroblasts, the greatest effect was for incomplete exchanges. For both lymphocytes and fibroblasts, iron ions induced a similar fraction of aberrant cells.

  20. Apigenin inhibits renal cell carcinoma cell proliferation

    PubMed Central

    Meng, Shuai; Zhu, Yi; Li, Jiang-Feng; Wang, Xiao; Liang, Zhen; Li, Shi-Qi; Xu, Xin; Chen, Hong; Liu, Ben; Zheng, Xiang-Yi; Xie, Li-Ping

    2017-01-01

    Apigenin, a natural flavonoid found in vegetables and fruits, has antitumor activity in several cancer types. The present study evaluated the effects and mechanism of action of apigenin in renal cell carcinoma (RCC) cells. We found that apigenin suppressed ACHN, 786-0, and Caki-1 RCC cell proliferation in a dose- and time-dependent manner. A comet assay suggested that apigenin caused DNA damage in ACHN cells, especially at higher doses, and induced G2/M phase cell cycle arrest through ATM signal modulation. Small interfering RNA (siRNA)-mediated p53 knockdown showed that apigenin-induced apoptosis was likely p53 dependent. Apigenin anti-proliferative effects were confirmed in an ACHN cell xenograft mouse model. Apigenin treatment reduced tumor growth and volume in vivo, and immunohistochemical staining revealed lower Ki-67 indices in tumors derived from apigenin-treated mice. These findings suggest that apigenin exposure induces DNA damage, G2/M phase cell cycle arrest, p53 accumulation and apoptosis, which collectively suppress ACHN RCC cell proliferation in vitro and in vivo. Given its antitumor effects and low in vivo toxicity, apigenin is a highly promising agent for treatment of RCC. PMID:28423637

  1. Apigenin inhibits renal cell carcinoma cell proliferation.

    PubMed

    Meng, Shuai; Zhu, Yi; Li, Jiang-Feng; Wang, Xiao; Liang, Zhen; Li, Shi-Qi; Xu, Xin; Chen, Hong; Liu, Ben; Zheng, Xiang-Yi; Xie, Li-Ping

    2017-03-21

    Apigenin, a natural flavonoid found in vegetables and fruits, has antitumor activity in several cancer types. The present study evaluated the effects and mechanism of action of apigenin in renal cell carcinoma (RCC) cells. We found that apigenin suppressed ACHN, 786-0, and Caki-1 RCC cell proliferation in a dose- and time-dependent manner. A comet assay suggested that apigenin caused DNA damage in ACHN cells, especially at higher doses, and induced G2/M phase cell cycle arrest through ATM signal modulation. Small interfering RNA (siRNA)-mediated p53 knockdown showed that apigenin-induced apoptosis was likely p53 dependent. Apigenin anti-proliferative effects were confirmed in an ACHN cell xenograft mouse model. Apigenin treatment reduced tumor growth and volume in vivo, and immunohistochemical staining revealed lower Ki-67 indices in tumors derived from apigenin-treated mice. These findings suggest that apigenin exposure induces DNA damage, G2/M phase cell cycle arrest, p53 accumulation and apoptosis, which collectively suppress ACHN RCC cell proliferation in vitro and in vivo. Given its antitumor effects and low in vivo toxicity, apigenin is a highly promising agent for treatment of RCC.

  2. Induction of chromosome aberrations and mitotic arrest by cytomegalovirus in human cells

    SciTech Connect

    AbuBakar, S.; Au, W.W.; Legator, M.S.

    1988-01-01

    Human cytomegalovirus (CMV) is potentially an effective but often overlooked genotoxic agent in humans. We report here evidence that indicates that infection by CMV can induce chromosome alterations and mitotic inhibition. The frequency of chromosome aberrations induced was dependent on the input multiplicity of infection (m.o.i.) for human lung fibroblasts (LU), but not for human peripheral blood lymphocytes (PBLs) when both cell types were infected at the GO phase of the cell cycle. The aberrations induced by CMV were mostly chromatid breaks and chromosome pulverizations that resembled prematurely condensed S-phase chromatin. Pulverized chromosomes were not observed in LU cells infectedmore » with virus stocks that had been rendered nonlytic by UV-irradiation at 24,000 ergs/mm2 or from infection of human lymphocytes. In LU cells infected with UV-irradiated CMV, the frequency of aberrations induced was inversely dependent on the extent of the exposure of the CMV stock to the UV-light. In permissive CMV infection of proliferating LU cells at 24 hr after subculture, a high percentage (greater than 40%) of the metaphase cells were arrested at their first metaphase and displayed severely condensed chromosomes when harvested 48 hr later. A significant increase (p less than 0.05) in the chromosome aberration frequency was also observed. Our study shows that CMV infection is genotoxic to host cells. The types and extent of damage are dependent on the viral genome expression and on the cell cycle stage of the cells at the time of infection. The possible mechanisms for induction of chromosome damage by CMV are discussed.« less

  3. ALG2 regulates glioblastoma cell proliferation, migration and tumorigenicity

    SciTech Connect

    Zhang, Dunke; Wang, Feng; Pang, Yi

    Apoptosis-linked gene-2 (ALG-2), also known as programmed cell death 6 (PDCD6), has recently been reported to be aberrantly expressed in various tumors and required for tumor cell viability. The aim of the present study was to investigate whether ALG-2 plays a crucial role in tumor cell proliferation, migration and tumorigenicity. In this study, we examined the expression of PDCD6 in glioblastoma cell lines and found that ALG-2 was generally expressed in glioblastoma cell lines. We also performed an analysis of an online database and found that high expression of ALG-2 was associated with poor prognosis (p = 0.039). We found that over-expressionmore » of ALG2 in glioblastoma could inhibit cell proliferation and, conversely, that down-regulation of ALG2 could promote cell proliferation. Further studies showed that over-expression of ALG2 inhibited the migration of tumor cells, whereas down-regulation of ALG2 promoted tumor cell migration. Finally, in vitro and in vivo studies showed that over-expression of ALG2 inhibited the tumorigenic ability of tumor cells, while down-regulation of ALG2 promoted tumor cell tumorigenic ability. In conclusion, ALG2 has a tumor suppressive role in glioblastoma and might be a potential target for the treatment of glioblastoma. - Highlights: • Low ALG2 expression is indicative of poor prognosis in glioblastoma patients. • ALG2 is required for cell proliferation in GBM cells. • ALG2 is involved in GBM cell migration. • ALG2 is involved in GBM cell self-renewal and tumorigenesis in vitro and in vivo.« less

  4. Aberrant epithelial GREM1 expression initiates colonic tumorigenesis from cells outside the stem cell niche.

    PubMed

    Davis, Hayley; Irshad, Shazia; Bansal, Mukesh; Rafferty, Hannah; Boitsova, Tatjana; Bardella, Chiara; Jaeger, Emma; Lewis, Annabelle; Freeman-Mills, Luke; Giner, Francesc Castro; Rodenas-Cuadrado, Pedro; Mallappa, Sreelakshmi; Clark, Susan; Thomas, Huw; Jeffery, Rosemary; Poulsom, Richard; Rodriguez-Justo, Manuel; Novelli, Marco; Chetty, Runjan; Silver, Andrew; Sansom, Owen James; Greten, Florian R; Wang, Lai Mun; East, James Edward; Tomlinson, Ian; Leedham, Simon John

    2015-01-01

    Hereditary mixed polyposis syndrome (HMPS) is characterized by the development of mixed-morphology colorectal tumors and is caused by a 40-kb genetic duplication that results in aberrant epithelial expression of the gene encoding mesenchymal bone morphogenetic protein antagonist, GREM1. Here we use HMPS tissue and a mouse model of the disease to show that epithelial GREM1 disrupts homeostatic intestinal morphogen gradients, altering cell fate that is normally determined by position along the vertical epithelial axis. This promotes the persistence and/or reacquisition of stem cell properties in Lgr5-negative progenitor cells that have exited the stem cell niche. These cells form ectopic crypts, proliferate, accumulate somatic mutations and can initiate intestinal neoplasia, indicating that the crypt base stem cell is not the sole cell of origin of colorectal cancer. Furthermore, we show that epithelial expression of GREM1 also occurs in traditional serrated adenomas, sporadic premalignant lesions with a hitherto unknown pathogenesis, and these lesions can be considered the sporadic equivalents of HMPS polyps.

  5. Myocilin Regulates Cell Proliferation and Survival*

    PubMed Central

    Joe, Myung Kuk; Kwon, Heung Sun; Cojocaru, Radu; Tomarev, Stanislav I.

    2014-01-01

    Myocilin, a causative gene for open angle glaucoma, encodes a secreted glycoprotein with poorly understood functions. To gain insight into its functions, we produced a stably transfected HEK293 cell line expressing myocilin under an inducible promoter and compared gene expression profiles between myocilin-expressing and vector control cell lines by a microarray analysis. A significant fraction of differentially expressed genes in myocilin-expressing cells was associated with cell growth and cell death, suggesting that myocilin may have a role in the regulation of cell growth and survival. Increased proliferation of myocilin-expressing cells was demonstrated by the WST-1 proliferation assay, direct cell counting, and immunostaining with antibodies against Ki-67, a cellular proliferation marker. Myocilin-containing conditioned medium also increased proliferation of unmodified HEK293 cells. Myocilin-expressing cells were more resistant to serum starvation-induced apoptosis than control cells. TUNEL-positive apoptotic cells were dramatically decreased, and two apoptotic marker proteins, cleaved caspase 7 and cleaved poly(ADP-ribose) polymerase, were significantly reduced in myocilin-expressing cells as compared with control cells under apoptotic conditions. In addition, myocilin-deficient mesenchymal stem cells exhibited reduced proliferation and enhanced susceptibility to serum starvation-induced apoptosis as compared with wild-type mesenchymal stem cells. Phosphorylation of ERK1/2 and its upstream kinases, c-Raf and MEK, was increased in myocilin-expressing cells compared with control cells. Elevated phosphorylation of ERK1/2 was also observed in the trabecular meshwork of transgenic mice expressing 6-fold higher levels of myocilin when compared with their wild-type littermates. These results suggest that myocilin promotes cell proliferation and resistance to apoptosis via the ERK1/2 MAPK signaling pathway. PMID:24563482

  6. Wnt signaling regulates pancreatic β cell proliferation

    PubMed Central

    Rulifson, Ingrid C.; Karnik, Satyajit K.; Heiser, Patrick W.; ten Berge, Derk; Chen, Hainan; Gu, Xueying; Taketo, Makoto M.; Nusse, Roel; Hebrok, Matthias; Kim, Seung K.

    2007-01-01

    There is widespread interest in defining factors and mechanisms that stimulate proliferation of pancreatic islet cells. Wnt signaling is an important regulator of organ growth and cell fates, and genes encoding Wnt-signaling factors are expressed in the pancreas. However, it is unclear whether Wnt signaling regulates pancreatic islet proliferation and differentiation. Here we provide evidence that Wnt signaling stimulates islet β cell proliferation. The addition of purified Wnt3a protein to cultured β cells or islets promoted expression of Pitx2, a direct target of Wnt signaling, and Cyclin D2, an essential regulator of β cell cycle progression, and led to increased β cell proliferation in vitro. Conditional pancreatic β cell expression of activated β-catenin, a crucial Wnt signal transduction protein, produced similar phenotypes in vivo, leading to β cell expansion, increased insulin production and serum levels, and enhanced glucose handling. Conditional β cell expression of Axin, a potent negative regulator of Wnt signaling, led to reduced Pitx2 and Cyclin D2 expression by β cells, resulting in reduced neonatal β cell expansion and mass and impaired glucose tolerance. Thus, Wnt signaling is both necessary and sufficient for islet β cell proliferation, and our study provides previously unrecognized evidence of a mechanism governing endocrine pancreas growth and function. PMID:17404238

  7. Investigation of an Aberrant Cell Voltage During the Filling of a Large Lithium Thionyl Chloride Cell

    NASA Technical Reports Server (NTRS)

    Thaller, Lawrence H.; Quinzio, Michael V.

    1997-01-01

    The investigation of an aberrant cell voltage during the filling of a large lithium thionyl chloride cell summary is at: an aberrant voltage trace was noted during the review of cell filling data; incident was traced to an interruption during filling; experimentation suggested oxidizable sites within the carbon electrode were responsible for the drop in voltage; the voltage anomaly could be reproduced by interrupting the filling of similar cells; and anomalous voltage dip was not due to a short.

  8. Effect of nickel chloride on cell proliferation.

    PubMed

    D'Antò, Vincenzo; Valletta, Rosa; Amato, Massimo; Schweikl, Helmut; Simeone, Michele; Paduano, Sergio; Rengo, Sandro; Spagnuolo, Gianrico

    2012-01-01

    Metal alloys used in dentistry and in other biomedical fields may release nickel ions in the oral environment. The release of nickel might influence the normal biological and physiological processes, including tissue wound healing, cell growth and proliferation. The aim of this study was to evaluate in vitro the effects of nickel ions on cell cycle, viability and proliferation. Human osteosarcoma cells (U2OS) and human keratinocytes (HaCat) were exposed to different nickel chloride (NiCl(2)) concentrations (0 - 5mM) for various periods exposure. The viability of cultured cells was estimated by flow cytometry using Annexin V-FITC and Propidium Iodide (PI). Cell proliferation was evaluated by using carboxyfluorescein diacetate succinimidyl ester (CFDA-SE) and flow cytometry. Finally, the effects of NiCl(2) on cell cycle were assessed and quantified by flow cytometry. Statistical analysis was performed by means of ANOVA followed by Tukey's test. NiCl(2) induced a dose and time dependent decrease in cell viability. After 24h, 1mM NiCl(2) caused a similar and significant reduction of viability in U2OS and HaCat cells, while higher NiCl(2) concentrations and longer exposure times showed a reduced cytotoxic effect in HaCat as compared to U2OS cells. Exposure to NiCl(2) caused a dose- and time-dependent inhibition of cell proliferation in both cell lines tested, with a prominent effect on U2OS cells. Furthermore, both cell lines exposed to NiCl(2) exhibited significant changes in cell cycle distribution after 24h exposure 2mM NiCl2, as compared to untreated cells (p<0.05). Our results indicate that release of nickel ions may affect cell proliferation. The inhibition of cell growth by NiCl2 is mediated by both cell cycle arrest and by induction of cell death.

  9. Lethality of radiation-induced chromosome aberrations in human tumour cell lines with different radiosensitivities.

    PubMed

    Coco-Martin, J M; Ottenheim, C P; Bartelink, H; Begg, A C

    1996-03-01

    In order to find an explanation for the eventual disappearance of all chromosome aberrations in two radiosensitive human tumour cell lines, the type and stability of different aberration types was investigated in more detail. To classify the aberrations into unstable and stable types, three-colour fluorescence in situ hybridization was performed, including a whole-chromosome probe, a pancentromere probe, and a stain for total DNA. This technique enables the appropriate classification of the aberrations principally by the presence (stable) or not (unstable) of a single centromere per chromosome. Unstable-type aberrations were found to disappear within 7 days (several divisions) in the two radiosensitive and the two radioresistant tumour lines investigated. Stable-type aberrations were found to remain at an approximately constant level over the duration of the experiment (14 days; 8-10 divisions) in the two radioresistant lines. In contrast, the majority of these stable-type aberrations had disappeared by 14 days in the two radiosensitive lines. The previous findings of disappearance of total aberrations in radiosensitive cells was therefore not due to a reduced induction of stable-type aberrations, but the complete disappearance of cells with this aberration type. These results could not be explained by differences in apoptosis or G1 blocks. Two possible explanations for these unexpected findings involve non-random induction of unstable-type aberrations, or lethality of stable-type aberrations. The results suggest caution in the use of stable-type aberration numbers as a predictor for radiosensitivity.

  10. Cell proliferation and differentiation in chemical leukemogenesis

    NASA Technical Reports Server (NTRS)

    Irons, R. D.; Stillman, W. S.; Clarkson, T. W. (Principal Investigator)

    1993-01-01

    In tissues such as bone marrow with normally high rates of cell division, proliferation is tightly coordinated with cell differentiation. Survival, proliferation and differentiation of early hematopoietic progenitor cells depend on the growth factors, interleukin 3 (IL-3) and/or granulocyte-macrophage colony stimulating factor (GM-CSF) and their synergism with other cytokines. We provide evidence that a characteristic shared by a diverse group of compounds with demonstrated leukemogenic potential is the ability to act synergistically with GM-CSF. This results in an increase in recruitment of a resting population of hematopoietic progenitor cells normally unresponsive to the cytokine and a twofold increase in the size of the proliferating cell population normally regarded to be at risk of transformation in leukemogenesis. These findings support the possibility that transient alterations in hematopoietic progenitor cell differentiation may be an important factor in the early stages of development of leukemia secondary to chemical or drug exposure.

  11. Protein corona of airborne nanoscale PM2.5 induces aberrant proliferation of human lung fibroblasts based on a 3D organotypic culture.

    PubMed

    Li, Yan; Wang, Pengcheng; Hu, Chuanlin; Wang, Kun; Chang, Qing; Liu, Lieju; Han, Zhenggang; Shao, Yang; Zhai, Ying; Zuo, Zhengyu; Mak, Michael; Gong, Zhiyong; Wu, Yang

    2018-01-31

    Exposure to PM2.5 has become one of the most important factors affecting public health in the world. Both clinical and research studies have suggested that PM2.5 inhalation is associated with impaired lung function. In this study, material characterization identified the existence of nanoscale particulate matter (NPM) in airborne PM2.5 samples. When coming into contact with protein-rich fluids, the NPM becomes covered by a protein layer that forms a "protein corona". Based on a 3D organotypic cell culture, the protein corona was shown to mitigate NPM cytotoxicity and further stimulate the proliferation of human lung fibroblasts (HLFs). ROS-activated alpha-smooth muscle actin (α-SMA) is considered to be one of the proliferation pathways. In this research, 3D cell cultures exhibited more tissue-like properties compared with the growth in 2D models. Animal models have been widely used in toxicological research. However, species differences make it impossible to directly translate discoveries from animals to humans. In this research, the 3D HLF model could partly simulate the biological responses of NPM-protein corona-induced aberrant HLF proliferation in the human lung. Our 3D cellular results provide auxiliary support for an animal model in research on PM2.5-induced impaired lung function, particularly in lung fibrosis.

  12. T-kininogen induces endothelial cell proliferation.

    PubMed

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

    2006-03-01

    Basal proliferation of endothelial cells increases with age, and this might play a role in the etiology of age-related vascular diseases, as well as angiogenesis. Serum kininogen levels increase during aging in rats and humans, and T-kininogen (T-KG) can affect proliferative homeostasis in several cell models. Both kinins and kininogens have been shown previously to be angiogenic through activation of endothelial cell proliferation, and here we show that exposure of endothelial cells to T-KG results in vigorous cell proliferation, accompanied by ERK/AKT activation. In our experiments, the proliferative response requires B1 and B2 kinin receptors, even though kinins are not released from the precursor. We hypothesize that the age-related increase in T-KG could play a significant role in the age-related dysregulation of vascular physiology and function.

  13. Blue light inhibits proliferation of melanoma cells

    NASA Astrophysics Data System (ADS)

    Becker, Anja; Distler, Elisabeth; Klapczynski, Anna; Arpino, Fabiola; Kuch, Natalia; Simon-Keller, Katja; Sticht, Carsten; van Abeelen, Frank A.; Gretz, Norbert; Oversluizen, Gerrit

    2016-03-01

    Photobiomodulation with blue light is used for several treatment paradigms such as neonatal jaundice, psoriasis and back pain. However, little is known about possible side effects concerning melanoma cells in the skin. The aim of this study was to assess the safety of blue LED irradiation with respect to proliferation of melanoma cells. For that purpose we used the human malignant melanoma cell line SK-MEL28. Cell proliferation was decreased in blue light irradiated cells where the effect size depended on light irradiation dosage. Furthermore, with a repeated irradiation of the melanoma cells on two consecutive days the effect could be intensified. Fluorescence-activated cell sorting with Annexin V and Propidium iodide labeling did not show a higher number of dead cells after blue light irradiation compared to non-irradiated cells. Gene expression analysis revealed down-regulated genes in pathways connected to anti-inflammatory response, like B cell signaling and phagosome. Most prominent pathways with up-regulation of genes were cytochrome P450, steroid hormone biosynthesis. Furthermore, even though cells showed a decrease in proliferation, genes connected to the cell cycle were up-regulated after 24h. This result is concordant with XTT test 48h after irradiation, where irradiated cells showed the same proliferation as the no light negative control. In summary, proliferation of melanoma cells can be decreased using blue light irradiation. Nevertheless, the gene expression analysis has to be further evaluated and more studies, such as in-vivo experiments, are warranted to further assess the safety of blue light treatment.

  14. Aberrant and multiaberrant (rogue) cells in peripheral lymphocytes of Hodgkin's lymphoma patients after chemotherapy.

    PubMed

    Ryabchenko, Nikolay I; Nasonova, Valentina A; Fesenko, Eleonora V; Kondrashova, Tatiana V; Antoschina, Margarita M; Pavlov, Vyacheslav V; Ryabikina, Natalya V

    2006-10-10

    We analyzed spontaneous chromosome lesions in peripheral lymphocytes cultured from Hodgkin's lymphoma (HL) patients before and after cytostatic chemotherapy. The mean aberration frequency was significantly higher in HL patients after chemotherapy (7.20+/-0.58 per 100 metaphases) than in non-treated HL patients (4.80+/-0.54), and in non-treated patients than in healthy subjects (2.12+/-0.13). In lymphocytes of HL patients, who received chemotherapy, we found, in addition to ordinary aberrant cells, a large number of multiaberrant (or rogue) cells, i.e. metaphases carrying multiple (at least four) chromosome-type exchange aberrations. Rogue cells were found in 15 out of 18 chemotherapeutically treated HL patients (in total, 60 rogue cells per 5,568 scored cells), whereas in 30 non-treated patients only 1 rogue cell was found (per 4,988 scored cells). No correlation was found between the yield of rogue cells and the aberration frequency in ordinary aberrant cells. Aberration spectra (ratios of chromatid- to chromosome-type aberrations and of breaks to exchanges) were essentially different in ordinary aberrant and multiaberrant cells. These data, as well as analysis of cellular distributions of aberrations, implied independent induction of chromosome damage in ordinary aberrant and rogue cells. Analysis of aberration patterns in diploid and polyploid rogue metaphases belonging to the first, second, and third in vitro division indicated that rogue cells could be formed both in vivo and in vitro, and could survive at least two rounds of in vitro replication, given blocked chromosome segregation. These results suggested that formation of rogue cells, unlike ordinary aberrant cells, was triggered by events other than direct DNA and/or chromosome lesions. A hypothesis regarding disrupted apoptosis as a candidate mechanism for rogue cell formation seems to be most suitable for interpretation of our data. Cultured lymphocytes of chemotherapeutically treated HL patients may

  15. Lensless imaging system to quantify cell proliferation

    NASA Astrophysics Data System (ADS)

    Vinjimore Kesavan, S.; Allier, C. P.; Navarro, F.; Mittler, F.; Chalmond, B.; Dinten, J.-M.

    2013-02-01

    Owing to its simplicity, lensless imaging system is adept at continuous monitoring of adherent cells inside the incubator. The setup consists of a CMOS sensor with pixel pitch of 2.2 μm and field of view of 24 mm2, LED with a dominating wavelength of 525 nm, along with a pinhole of 150 μm as the source of illumination. The in-line hologram obtained from cells depends on the degree of cell-substrate adhesion. Drastic difference is observed between the holographic patterns of floating and adherent cells. In addition, the well-established fact of reduction of cell-substrate contact during cell division is observed with our system based on corresponding spontaneous transition in the holographic pattern. Here, we demonstrate that by recognizing this specific holographic pattern, number of cells undergoing mitosis in a cell culture with a population of approximately 5000 cells, can be estimated in real-time. The method is assessed on comparison with Edu-based proliferation assay. The approach is straightforward and it eliminates the use of markers to estimate the proliferation rate of a given cell culture. Unlike most proliferation assays, the cells are not harvested enabling continuous monitoring of cell culture.

  16. TWEAK induces liver progenitor cell proliferation

    PubMed Central

    Jakubowski, Aniela; Ambrose, Christine; Parr, Michael; Lincecum, John M.; Wang, Monica Z.; Zheng, Timothy S.; Browning, Beth; Michaelson, Jennifer S.; Baestcher, Manfred; Wang, Bruce; Bissell, D. Montgomery; Burkly, Linda C.

    2005-01-01

    Progenitor (“oval”) cell expansion accompanies many forms of liver injury, including alcohol toxicity and submassive parenchymal necrosis as well as experimental injury models featuring blocked hepatocyte replication. Oval cells can potentially become either hepatocytes or biliary epithelial cells and may be critical to liver regeneration, particularly when hepatocyte replication is impaired. The regulation of oval cell proliferation is incompletely understood. Herein we present evidence that a TNF family member called TWEAK (TNF-like weak inducer of apoptosis) stimulates oval cell proliferation in mouse liver through its receptor Fn14. TWEAK has no effect on mature hepatocytes and thus appears to be selective for oval cells. Transgenic mice overexpressing TWEAK in hepatocytes exhibit periportal oval cell hyperplasia. A similar phenotype was obtained in adult wild-type mice, but not Fn14-null mice, by administering TWEAK-expressing adenovirus. Oval cell expansion induced by 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) was significantly reduced in Fn14-null mice as well as in adult wild-type mice with a blocking anti-TWEAK mAb. Importantly, TWEAK stimulated the proliferation of an oval cell culture model. Finally, we show increased Fn14 expression in chronic hepatitis C and other human liver diseases relative to its expression in normal liver, which suggests a role for the TWEAK/Fn14 pathway in human liver injury. We conclude that TWEAK has a selective mitogenic effect for liver oval cells that distinguishes it from other previously described growth factors. PMID:16110324

  17. Effect of Nickel Chloride on Cell Proliferation

    PubMed Central

    D’Antò, Vincenzo; Valletta, Rosa; Amato, Massimo; Schweikl, Helmut; Simeone, Michele; Paduano, Sergio; Rengo, Sandro; Spagnuolo, Gianrico

    2012-01-01

    Objective: Metal alloys used in dentistry and in other biomedical fields may release nickel ions in the oral environment. The release of nickel might influence the normal biological and physiological processes, including tissue wound healing, cell growth and proliferation. The aim of this study was to evaluate in vitro the effects of nickel ions on cell cycle, viability and proliferation. Materials and Methods: Human osteosarcoma cells (U2OS) and human keratinocytes (HaCat) were exposed to different nickel chloride (NiCl2) concentrations (0 - 5mM) for various periods exposure. The viability of cultured cells was estimated by flow cytometry using Annexin V-FITC and Propidium Iodide (PI). Cell proliferation was evaluated by using carboxyfluorescein diacetate succinimidyl ester (CFDA-SE) and flow cytometry. Finally, the effects of NiCl2 on cell cycle were assessed and quantified by flow cytometry. Statistical analysis was performed by means of ANOVA followed by Tukey’s test. Results: NiCl2 induced a dose and time dependent decrease in cell viability. After 24h, 1mM NiCl2 caused a similar and significant reduction of viability in U2OS and HaCat cells, while higher NiCl2 concentrations and longer exposure times showed a reduced cytotoxic effect in HaCat as compared to U2OS cells. Exposure to NiCl2 caused a dose- and time-dependent inhibition of cell proliferation in both cell lines tested, with a prominent effect on U2OS cells. Furthermore, both cell lines exposed to NiCl2 exhibited significant changes in cell cycle distribution after 24h exposure 2mM NiCl2, as compared to untreated cells (p<0.05). Conclusion: Our results indicate that release of nickel ions may affect cell proliferation. The inhibition of cell growth by NiCl2 is mediated by both cell cycle arrest and by induction of cell death. PMID:23198004

  18. Aberrant T Cell Signaling and Subsets in Systemic Lupus Erythematosus.

    PubMed

    Katsuyama, Takayuki; Tsokos, George C; Moulton, Vaishali R

    2018-01-01

    Systemic lupus erythematosus (SLE) is a chronic multi-organ debilitating autoimmune disease, which mainly afflicts women in the reproductive years. A complex interaction of genetics, environmental factors and hormones result in the breakdown of immune tolerance to "self" leading to damage and destruction of multiple organs, such as the skin, joints, kidneys, heart and brain. Both innate and adaptive immune systems are critically involved in the misguided immune response against self-antigens. Dendritic cells, neutrophils, and innate lymphoid cells are important in initiating antigen presentation and propagating inflammation at lymphoid and peripheral tissue sites. Autoantibodies produced by B lymphocytes and immune complex deposition in vital organs contribute to tissue damage. T lymphocytes are increasingly being recognized as key contributors to disease pathogenesis. CD4 T follicular helper cells enable autoantibody production, inflammatory Th17 subsets promote inflammation, while defects in regulatory T cells lead to unchecked immune responses. A better understanding of the molecular defects including signaling events and gene regulation underlying the dysfunctional T cells in SLE is necessary to pave the path for better management, therapy, and perhaps prevention of this complex disease. In this review, we focus on the aberrations in T cell signaling in SLE and highlight therapeutic advances in this field.

  19. Aberrant T Cell Signaling and Subsets in Systemic Lupus Erythematosus

    PubMed Central

    Katsuyama, Takayuki; Tsokos, George C.; Moulton, Vaishali R.

    2018-01-01

    Systemic lupus erythematosus (SLE) is a chronic multi-organ debilitating autoimmune disease, which mainly afflicts women in the reproductive years. A complex interaction of genetics, environmental factors and hormones result in the breakdown of immune tolerance to “self” leading to damage and destruction of multiple organs, such as the skin, joints, kidneys, heart and brain. Both innate and adaptive immune systems are critically involved in the misguided immune response against self-antigens. Dendritic cells, neutrophils, and innate lymphoid cells are important in initiating antigen presentation and propagating inflammation at lymphoid and peripheral tissue sites. Autoantibodies produced by B lymphocytes and immune complex deposition in vital organs contribute to tissue damage. T lymphocytes are increasingly being recognized as key contributors to disease pathogenesis. CD4 T follicular helper cells enable autoantibody production, inflammatory Th17 subsets promote inflammation, while defects in regulatory T cells lead to unchecked immune responses. A better understanding of the molecular defects including signaling events and gene regulation underlying the dysfunctional T cells in SLE is necessary to pave the path for better management, therapy, and perhaps prevention of this complex disease. In this review, we focus on the aberrations in T cell signaling in SLE and highlight therapeutic advances in this field. PMID:29868033

  20. Homeobox A7 stimulates breast cancer cell proliferation by up-regulating estrogen receptor-alpha

    SciTech Connect

    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

  1. Effects of brevetoxins on murine myeloma SP2/O cells: Aberrant cellular division

    USGS Publications Warehouse

    Han, T.K.; Derby, M.; Martin, D.F.; Wright, S.D.; Dao, M.L.

    2003-01-01

    Massive deaths of manatees (Trichechus manatus latirostris) during the red tide seasons have been attributed to brevetoxins produced by the dinoflagellate Karenia brevis (formerly Ptychodiscus breve and Gymnodinium breve). Although these toxins have been found in macrophages and lymphocytes in the lung, liver, and secondary lymphoid tissues of these animals, the molecular mechanisms of brevetoxicosis have not yet been identified. To investigate the effects of brevetoxins on immune cells, a murine myeloma cell line (SP2/O) was used as a model for in vitro studies. By adding brevetoxins to cultures of the SP2/O cells at concentrations ranging from 20 to 600 ng/ml, an apparent increase in proliferation was observed at around 2 hours post challenge as compared to the unchallenged cell cultures. This was followed by a drop in cell number at around 3 hours, suggesting an aberrant effect of brevetoxins on cellular division, the cells generated at 2 hours being apparently short-lived. In situ immunochemical staining of the SP2/O cells at 1 and 2 hour post challenge showed an accumulation of the toxins in the nucleus. A 21-kDa protein was subsequently isolated from the SP2/O cells as having brevetoxin-binding properties, and immunologically identified as p21, a nuclear factor known to down-regulate cellular proliferation through inhibition of cyclin-dependent kinases. These data are the first on a possible effect of brevetoxins on the cell cycle via binding to p21, a phenomenon that needs to be further investigated and validated in normal immune cells.

  2. Microfluidic devices for cell cultivation and proliferation

    PubMed Central

    Tehranirokh, Masoomeh; Kouzani, Abbas Z.; Francis, Paul S.; Kanwar, Jagat R.

    2013-01-01

    Microfluidic technology provides precise, controlled-environment, cost-effective, compact, integrated, and high-throughput microsystems that are promising substitutes for conventional biological laboratory methods. In recent years, microfluidic cell culture devices have been used for applications such as tissue engineering, diagnostics, drug screening, immunology, cancer studies, stem cell proliferation and differentiation, and neurite guidance. Microfluidic technology allows dynamic cell culture in microperfusion systems to deliver continuous nutrient supplies for long term cell culture. It offers many opportunities to mimic the cell-cell and cell-extracellular matrix interactions of tissues by creating gradient concentrations of biochemical signals such as growth factors, chemokines, and hormones. Other applications of cell cultivation in microfluidic systems include high resolution cell patterning on a modified substrate with adhesive patterns and the reconstruction of complicated tissue architectures. In this review, recent advances in microfluidic platforms for cell culturing and proliferation, for both simple monolayer (2D) cell seeding processes and 3D configurations as accurate models of in vivo conditions, are examined. PMID:24273628

  3. Pancreatic β-cell proliferation in obesity.

    PubMed

    Linnemann, Amelia K; Baan, Mieke; Davis, Dawn Belt

    2014-05-01

    Because obesity rates have increased dramatically over the past 3 decades, type 2 diabetes has become increasingly prevalent as well. Type 2 diabetes is associated with decreased pancreatic β-cell mass and function, resulting in inadequate insulin production. Conversely, in nondiabetic obesity, an expansion in β-cell mass occurs to provide sufficient insulin and to prevent hyperglycemia. This expansion is at least in part due to β-cell proliferation. This review focuses on the mechanisms regulating obesity-induced β-cell proliferation in humans and mice. Many factors have potential roles in the regulation of obesity-driven β-cell proliferation, including nutrients, insulin, incretins, hepatocyte growth factor, and recently identified liver-derived secreted factors. Much is still unknown about the regulation of β-cell replication, especially in humans. The extracellular signals that activate proliferative pathways in obesity, the relative importance of each of these pathways, and the extent of cross-talk between these pathways are important areas of future study. © 2014 American Society for Nutrition.

  4. Mast cell desensitization inhibits calcium flux and aberrantly remodels actin

    PubMed Central

    Ang, W.X. Gladys; Church, Alison M.; Kulis, Mike; Choi, Hae Woong; Burks, A. Wesley

    2016-01-01

    Rush desensitization (DS) is a widely used and effective clinical strategy for the rapid inhibition of IgE-mediated anaphylactic responses. However, the cellular targets and underlying mechanisms behind this process remain unclear. Recent studies have implicated mast cells (MCs) as the primary target cells for DS. Here, we developed a murine model of passive anaphylaxis with demonstrated MC involvement and an in vitro assay to evaluate the effect of DS on MCs. In contrast with previous reports, we determined that functional IgE remains on the cell surface of desensitized MCs following DS. Despite notable reductions in MC degranulation following DS, the high-affinity IgE receptor FcεRI was still capable of transducing signals in desensitized MCs. Additionally, we found that displacement of the actin cytoskeleton and its continued association with FcεRI impede the capacity of desensitized MCs to evoke the calcium response that is essential for MC degranulation. Together, these findings suggest that reduced degranulation responses in desensitized MCs arise from aberrant actin remodeling, providing insights that may lead to improvement of DS treatments for anaphylactic responses. PMID:27669462

  5. Uterine epithelial cell proliferation and endometrial hyperplasia: evidence from a mouse model

    PubMed Central

    Gao, Yang; Li, Shu; Li, Qinglei

    2014-01-01

    In the uterus, epithelial cell proliferation changes during the estrous cycle and pregnancy. Uncontrolled epithelial cell proliferation results in implantation failure and/or cancer development. Transforming growth factor-β (TGF-β) signaling is a fundamental regulator of diverse biological processes and is indispensable for multiple reproductive functions. However, the in vivo role of TGF-β signaling in uterine epithelial cells remains poorly defined. We have shown that in the uterus, conditional deletion of the Type 1 receptor for TGF-β (Tgfbr1) using anti-Müllerian hormone receptor type 2 (Amhr2) Cre leads to myometrial defects. Here, we describe enhanced epithelial cell proliferation by immunostaining of Ki67 in the uteri of these mice. The aberration culminated in endometrial hyperplasia in aged females. To exclude the potential influence of ovarian steroid hormones, the proliferative status of uterine epithelial cells was assessed following ovariectomy. Increased uterine epithelial cell proliferation was also revealed in ovariectomized Tgfbr1 Amhr2-Cre conditional knockout mice. We further demonstrated that transcript levels for fibroblast growth factor 10 (Fgf10) were markedly up-regulated in Tgfbr1 Amhr2-Cre conditional knockout uteri. Consistently, treatment of primary uterine stromal cells with TGF-β1 significantly reduced Fgf10 mRNA expression. Thus, our findings suggest a potential involvement of TGFBR1-mediated signaling in the regulation of uterine epithelial cell proliferation, and provide genetic evidence supporting the role of uterine epithelial cell proliferation in the pathogenesis of endometrial hyperplasia. PMID:24770950

  6. Peroxisome proliferators induce apoptosis in hepatoma cells.

    PubMed

    Canuto, R A; Muzio, G; Bonelli, G; Maggiora, M; Autelli, R; Barbiero, G; Costelli, P; Brossa, O; Baccino, F M

    1998-01-01

    In the AH-130 hepatoma, a poorly differentiated tumor, maintained by weekly transplantations in rats, a low percentage of cells spontaneously underwent apoptosis, mainly during the transition from logarithmic- to stationary-growth phase. It was possible to induce massive apoptosis of cells by treating them with clofibrate, a peroxisome proliferator and hypolipidemic drug. Similar results were obtained with HepG2 cells. With 1 mM clofibrate, apoptosis began to manifest itself after 1 h of treatment in vitro, and was assessed by morphological analysis, by DNA fragmentation carried out with agarose gel electrophoresis, and with flow cytometric determination of terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling. The mechanisms whereby clofibrate induces apoptosis are still unclear. Since the peroxisome proliferator-activated receptor was expressed at a very low level and was not stimulated by clofibrate in the AH-130 hepatoma cells, its involvement seems unlikely. Moreover, lipid peroxidation was not increased after clofibrate treatment. Phospholipids and cholesterol were significantly decreased. The decreased cholesterol content might suggest an inhibition of the mevalonate pathway and, therefore, of isoprenylation of proteins involved in cell proliferation.

  7. BCOR regulates myeloid cell proliferation and differentiation

    PubMed Central

    Cao, Qi; Gearhart, Micah D.; Gery, Sigal; Shojaee, Seyedmehdi; Yang, Henry; Sun, Haibo; Lin, De-chen; Bai, Jing-wen; Mead, Monica; Zhao, Zhiqiang; Chen, Qi; Chien, Wen-wen; Alkan, Serhan; Alpermann, Tamara; Haferlach, Torsten; Müschen, Markus; Bardwell, Vivian J.; Koeffler, H. Phillip

    2016-01-01

    BCOR is a component of a variant Polycomb group repressive complex 1 (PRC1). Recently, we and others reported recurrent somatic BCOR loss-of-function mutations in myelodysplastic syndrome and acute myelogenous leukaemia (AML). However, the role of BCOR in normal hematopoiesis is largely unknown. Here, we explored the function of BCOR in myeloid cells using myeloid murine models with Bcor conditional loss-of-function or overexpression alleles. Bcor mutant bone marrow cells showed significantly higher proliferation and differentiation rates with upregulated expression of Hox genes. Mutation of Bcor reduced protein levels of RING1B, an H2A ubiquitin ligase subunit of PRC1 family complexes and reduced H2AK119ub upstream of upregulated HoxA genes. Global RNA expression profiling in murine cells and AML patient samples with BCOR loss-of-function mutation suggested that loss of BCOR expression is associated with enhanced cell proliferation and myeloid differentiation. Our results strongly suggest that BCOR plays an indispensable role in hematopoiesis by inhibiting myeloid cell proliferation and differentiation and offer a mechanistic explanation for how BCOR regulates gene expression such as Hox genes. PMID:26847029

  8. MicroRNA-196b promotes cell proliferation and suppress cell differentiation in vitro

    SciTech Connect

    Cao, Donglin, E-mail: caodlgz@sina.com; Hu, Liangshan; Lei, Da

    Highlights: • miRNA-196b increases proliferation and blocks differentiation of progenitor cell. • miRNA-196b inhibits apoptosis and increases viability of cells lines. • Forced expression of miR-196b blocks the differentiation of THP1 induced by PMA. - Abstract: MicroRNA-196b (miR-196b) is frequently amplified and aberrantly overexpressed in acute leukemias. To investigate the role of miR-196b in acute leukemias, it has been observed that forced expression of this miRNA increases proliferation and inhibits apoptosis in human cell lines. More importantly, we show that this miRNA can significantly increase the colony-forming capacity of mouse normal bone marrow progenitor cells alone, as well as partiallymore » blocking the cells from differentiation. Taken together, our studies suggest that miRNA-196b may play an essential role in the development of MLL-associated leukemias through inhibiting cell differentiation and apoptosis, while promoting cell proliferation.« less

  9. Cell proliferation inhibition in reduced gravity

    NASA Technical Reports Server (NTRS)

    Moos, P. J.; Fattaey, H. K.; Johnson, T. C.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    Extended durations of spaceflight have been shown to be deleterious on an organismic level; however, mechanisms underlying cellular sensitivity to the gravitational environment remain to be elucidated. The majority of the gravitational studies to date indicates that cell regulatory pathways may be influenced by their gravitational environment. Still, few cell biology experiments have been performed in space flight and even fewer experiments have been repeated on subsequent flights. With flight opportunities on STS-50, 54, and 57, Sf9 cells were flown in the BioServe Fluids Processing Apparatus and cell proliferation was measured with and without exposure to a cell regulatory sialoglycopeptide (CeReS) inhibitor. Results from these flights indicate that the Sf9 cells grew comparable to ground controls, that the CeReS inhibitor bound to its specific receptor, and that its signal transduction cascade was not gravity sensitive.

  10. Mitochondrial Regulation of Cell Cycle and Proliferation

    PubMed Central

    Antico Arciuch, Valeria Gabriela; Elguero, María Eugenia; Poderoso, Juan José

    2012-01-01

    Abstract Eukaryotic mitochondria resulted from symbiotic incorporation of α-proteobacteria into ancient archaea species. During evolution, mitochondria lost most of the prokaryotic bacterial genes and only conserved a small fraction including those encoding 13 proteins of the respiratory chain. In this process, many functions were transferred to the host cells, but mitochondria gained a central role in the regulation of cell proliferation and apoptosis, and in the modulation of metabolism; accordingly, defective organelles contribute to cell transformation and cancer, diabetes, and neurodegenerative diseases. Most cell and transcriptional effects of mitochondria depend on the modulation of respiratory rate and on the production of hydrogen peroxide released into the cytosol. The mitochondrial oxidative rate has to remain depressed for cell proliferation; even in the presence of O2, energy is preferentially obtained from increased glycolysis (Warburg effect). In response to stress signals, traffic of pro- and antiapoptotic mitochondrial proteins in the intermembrane space (B-cell lymphoma-extra large, Bcl-2-associated death promoter, Bcl-2 associated X-protein and cytochrome c) is modulated by the redox condition determined by mitochondrial O2 utilization and mitochondrial nitric oxide metabolism. In this article, we highlight the traffic of the different canonical signaling pathways to mitochondria and the contributions of organelles to redox regulation of kinases. Finally, we analyze the dynamics of the mitochondrial population in cell cycle and apoptosis. Antioxid. Redox Signal. 16, 1150–1180. PMID:21967640

  11. Sonic Hedgehog promotes proliferation of Notch-dependent monociliated choroid plexus tumour cells

    PubMed Central

    Li, Li; Grausam, Katie B.; Wang, Jun; Lun, Melody P.; Ohli, Jasmin; Lidov, Hart G. W.; Calicchio, Monica L.; Zeng, Erliang; Salisbury, Jeffrey L.; Wechsler-Reya, Robert J.; Lehtinen, Maria K.; Schüller, Ulrich; Zhao, Haotian

    2016-01-01

    Aberrant Notch signaling has been linked to many cancers including choroid plexus (CP) tumours, a group of rare and predominantly pediatric brain neoplasms. We developed animal models of CP tumours by inducing sustained expression of Notch1 that recapitulate properties of human CP tumours with aberrant NOTCH signaling. Whole transcriptome and functional analyses showed that tumour cell proliferation is associated with Sonic Hedgehog (Shh) in the tumour microenvironment. Unlike CP epithelial cells, which have multiple primary cilia, tumour cells possess a solitary primary cilium as a result of Notch-mediated suppression of multiciliate diffferentiation. A Shh-driven signaling cascade in the primary cilium occurs in tumour cells but not in epithelial cells. Lineage studies show that CP tumours arise from mono-ciliated progenitors in the roof plate characterized by elevated Notch signaling. Abnormal SHH signaling and distinct ciliogenesis are detected in human CP tumours, suggesting SHH pathway and cilia differentiation as potential therapeutic avenues. PMID:26999738

  12. Biofilms’ Role in Planktonic Cell Proliferation

    PubMed Central

    Bester, Elanna; Wolfaardt, Gideon M.; Aznaveh, Nahid B.; Greener, Jesse

    2013-01-01

    The detachment of single cells from biofilms is an intrinsic part of this surface-associated mode of bacterial existence. Pseudomonas sp. strain CT07gfp biofilms, cultivated in microfluidic channels under continuous flow conditions, were subjected to a range of liquid shear stresses (9.42 mPa to 320 mPa). The number of detached planktonic cells was quantified from the effluent at 24-h intervals, while average biofilm thickness and biofilm surface area were determined by confocal laser scanning microscopy and image analysis. Biofilm accumulation proceeded at the highest applied shear stress, while similar rates of planktonic cell detachment was maintained for biofilms of the same age subjected to the range of average shear rates. The conventional view of liquid-mediated shear leading to the passive erosion of single cells from the biofilm surface, disregards the active contribution of attached cell metabolism and growth to the observed detachment rates. As a complement to the conventional conceptual biofilm models, the existence of a biofilm surface-associated zone of planktonic cell proliferation is proposed to highlight the need to expand the traditional perception of biofilms as promoting microbial survival, to include the potential of biofilms to contribute to microbial proliferation. PMID:24201127

  13. Micronuclei versus Chromosomal Aberrations Induced by X-Ray in Radiosensitive Mammalian Cells.

    PubMed

    Plamadeala, Cristina; Wojcik, Andrzej; Creanga, Dorina

    2015-03-01

    An experimental study was accomplished to compare estimation methods of ionizing radiations genotoxicity in mammalian cell cultures by means of two cytogenetic parameters with focus on aberrant cells characterized by multiple chromosomal damages. In vitro study was carried out on the genotoxicity of low-medium doses of 190 kV X-rays absorbed in Chinese hamster ovary cell cultures. Micronuclei and ten types of chromosomal aberrations were identified with Giemsa dying and optical microscope screening. The first parameter consisting in micronuclei relative frequency has led to higher linear correlation coefficient than the second one consistent with chromosomal aberrations relative frequency. However, the latter parameter estimated as the sum of all chromosomal aberrations appeared to be more sensitive to radiation dose increasing in the studied dose range, from 0 to 3 Gy. The number of micronuclei occurring simultaneously in a single cell was not higher than 3, while the number of chromosomal aberrations observed in the same cell reached the value of 5 for doses over 1 Gy. Polynomial dose-response curves were evidenced for cells with Ni micronuclei (i=1,3) while non-monotonic curves were evidenced through detailed analysis of aberrant cells with Ni chromosomal changes [Formula: see text] - in concordance with in vitro studies from literature. The investigation could be important for public health issues where micronucleus screening is routinely applied but also for research purposes where various chromosomal aberrations could be of particular interest.

  14. Micronuclei versus Chromosomal Aberrations Induced by X-Ray in Radiosensitive Mammalian Cells

    PubMed Central

    PLAMADEALA, Cristina; WOJCIK, Andrzej; CREANGA, Dorina

    2015-01-01

    Background: An experimental study was accomplished to compare estimation methods of ionizing radiations genotoxicity in mammalian cell cultures by means of two cytogenetic parameters with focus on aberrant cells characterized by multiple chromosomal damages. Methods: In vitro study was carried out on the genotoxicity of low-medium doses of 190 kV X-rays absorbed in Chinese hamster ovary cell cultures. Micronuclei and ten types of chromosomal aberrations were identified with Giemsa dying and optical microscope screening. Results: The first parameter consisting in micronuclei relative frequency has led to higher linear correlation coefficient than the second one consistent with chromosomal aberrations relative frequency. However, the latter parameter estimated as the sum of all chromosomal aberrations appeared to be more sensitive to radiation dose increasing in the studied dose range, from 0 to 3 Gy. The number of micronuclei occurring simultaneously in a single cell was not higher than 3, while the number of chromosomal aberrations observed in the same cell reached the value of 5 for doses over 1 Gy. Conclusion: Polynomial dose-response curves were evidenced for cells with Ni micronuclei (i=1,3) while non-monotonic curves were evidenced through detailed analysis of aberrant cells with Ni chromosomal changes (i=(1,5)¯) - in concordance with in vitro studies from literature. The investigation could be important for public health issues where micronucleus screening is routinely applied but also for research purposes where various chromosomal aberrations could be of particular interest. PMID:25905075

  15. CRMP2 Phosphorylation Drives Glioblastoma Cell Proliferation.

    PubMed

    Moutal, Aubin; Villa, Lex Salas; Yeon, Seul Ki; Householder, Kyle T; Park, Ki Duk; Sirianni, Rachael W; Khanna, Rajesh

    2018-05-01

    Glioblastoma (GBM) is an aggressive primary brain tumor. The rapid growth and the privileged provenance of the tumor within the brain contribute to its aggressivity and poor therapeutic targeting. A poor prognostic factor in glioblastoma is the deletion or mutation of the Nf1 gene. This gene codes for the protein neurofibromin, a tumor suppressor gene that is known to interact with the collapsin response mediator protein 2 (CRMP2). CRMP2 expression and elevated expression of nuclear phosphorylated CRMP2 have recently been implicated in cancer progression. The CRMP2-neurofibromin interaction protects CRMP2 from its phosphorylation by cyclin-dependent kinase 5 (Cdk5), an event linked to cancer progression. In three human glioblastoma cell lines (GL15, A172, and U87), we observed an inverse correlation between neurofibromin expression and CRMP2 phosphorylation levels. Glioblastoma cell proliferation was dependent on CRMP2 expression and phosphorylation by Cdk5 and glycogen synthase kinase 3 beta (GSK3β). The CRMP2 phosphorylation inhibitor (S)-lacosamide reduces, in a concentration-dependent manner, glioblastoma cell proliferation and induced apoptosis in all three GBM cell lines tested. Since (S)-lacosamide is bioavailable in the brain, we tested its utility in an in vivo orthotopic model of GBM using GL261-LucNeo glioma cells. (S)-lacosamide decreased tumor size, as measured via in vivo bioluminescence imaging, by ~54% compared to vehicle control. Our results introduce CRMP2 expression and phosphorylation as a novel player in GBM proliferation and survival, which is enhanced by loss of Nf1.

  16. LKB1 Regulates Cerebellar Development by Controlling Sonic Hedgehog-mediated Granule Cell Precursor Proliferation and Granule Cell Migration.

    PubMed

    Men, Yuqin; Zhang, Aizhen; Li, Haixiang; Jin, Yecheng; Sun, Xiaoyang; Li, Huashun; Gao, Jiangang

    2015-11-09

    The Liver Kinase B1 (LKB1) gene plays crucial roles in cell differentiation, proliferation and the establishment of cell polarity. We created LKB1 conditional knockout mice (LKB1(Atoh1) CKO) to investigate the function of LKB1 in cerebellar development. The LKB1(Atoh1) CKO mice displayed motor dysfunction. In the LKB1(Atoh1) CKO cerebellum, the overall structure had a larger volume and more lobules. LKB1 inactivation led to an increased proliferation of granule cell precursors (GCPs), aberrant granule cell migration and overproduction of unipolar brush cells. To investigate the mechanism underlying the abnormal foliation, we examined sonic hedgehog signalling (Shh) by testing its transcriptional mediators, the Gli proteins, which regulate the GCPs proliferation and cerebellar foliation during cerebellar development. The expression levels of Gli genes were significantly increased in the mutant cerebellum. In vitro assays showed that the proliferation of cultured GCPs from mutant cerebellum significantly increased, whereas the proliferation of mutant GCPs significantly decreased in the presence of a Shh inhibitor GDC-0049. Thus, LKB1 deficiency in the LKB1(Atoh1) CKO mice enhanced Shh signalling, leading to the excessive GCP proliferation and the formation of extra lobules. We proposed that LKB1 regulates cerebellar development by controlling GCPs proliferation through Shh signalling during cerebellar development.

  17. LKB1 Regulates Cerebellar Development by Controlling Sonic Hedgehog-mediated Granule Cell Precursor Proliferation and Granule Cell Migration

    PubMed Central

    Men, Yuqin; Zhang, Aizhen; Li, Haixiang; Jin, Yecheng; Sun, Xiaoyang; Li, Huashun; Gao, Jiangang

    2015-01-01

    The Liver Kinase B1 (LKB1) gene plays crucial roles in cell differentiation, proliferation and the establishment of cell polarity. We created LKB1 conditional knockout mice (LKB1Atoh1 CKO) to investigate the function of LKB1 in cerebellar development. The LKB1Atoh1 CKO mice displayed motor dysfunction. In the LKB1Atoh1 CKO cerebellum, the overall structure had a larger volume and morelobules. LKB1 inactivationled to an increased proliferation of granule cell precursors (GCPs), aberrant granule cell migration and overproduction of unipolar brush cells. To investigate the mechanism underlying the abnormal foliation, we examined sonic hedgehog signalling (Shh) by testing its transcriptional mediators, the Gli proteins, which regulate the GCPs proliferation and cerebellar foliation during cerebellar development. The expression levels of Gli genes were significantly increased in the mutant cerebellum. In vitro assays showed that the proliferation of cultured GCPs from mutant cerebellum significantly increased, whereas the proliferation of mutant GCPs significantly decreased in the presence of a Shh inhibitor GDC-0049. Thus, LKB1 deficiency in the LKB1Atoh1 CKO mice enhanced Shh signalling, leading to the excessive GCP proliferation and the formation of extra lobules. We proposed that LKB1 regulates cerebellar development by controlling GCPs proliferation through Shh signalling during cerebellar development. PMID:26549569

  18. Nucleoplasmic calcium regulates cell proliferation through legumain.

    PubMed

    Andrade, Viviane; Guerra, Mateus; Jardim, Camila; Melo, Flavia; Silva, Wamberto; Ortega, Jose M; Robert, Marie; Nathanson, Michael H; Leite, Fatima

    2011-09-01

    Nucleoplasmic Ca(2+) regulates cell growth in the liver, but the proteins through which this occurs are unknown. We used Rapid Subtraction Hybridization (RaSH) to subtract genes in SKHep1 liver cells expressing the Ca(2+) buffer protein parvalbumin (PV) targeted to the nucleus, from genes in cells expressing a mutated form of nuclear-targeted PV which has one of two Ca(2+)-binding sites inactivated. The subtraction permitted the selection of genes whose expression was affected by a small alteration in nuclear Ca(2+) concentration. The asparaginyl endopeptidase legumain (LGMN) was identified in this screening. When Ca(2+) was buffered in the nucleus of SKHep1 cells, LGMN mRNA was decreased by 97%, in part by a transcriptional mechanism, and decreased expression at the protein level was observed by immunoblot and immunofluorescence. Treatment with hepatocyte growth factor increased LGMN expression. Knockdown of LGMN by siRNA decreased proliferation of SKHep1 cells by ∼50% as measured both by BrdU uptake and mitotic index, although an inhibitor of LGMN activity did not affect BrdU incorporation. A significant reduction in the fraction of cells in G2/M phase was seen as well. This was associated with increases in the expression of cyclins A and E. Furthermore, LGMN expression was increased in hepatocellular carcinoma cells relative to normal hepatocytes in the same specimens. These findings suggest a new role for LGMN and provide evidence that nuclear Ca(2+) signals regulate cell proliferation in part through the modulation of LGMN expression. Increased expression of LGMN may be involved in liver carcinogenesis. Copyright © 2011 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  19. Proliferating cell nuclear antigen (PCNA): a new marker to study human colonic cell proliferation.

    PubMed Central

    Kubben, F J; Peeters-Haesevoets, A; Engels, L G; Baeten, C G; Schutte, B; Arends, J W; Stockbrügger, R W; Blijham, G H

    1994-01-01

    Immunohistochemistry of the S phase related proliferating cell nuclear antigen (PCNA) was studied as an alternative to ex-vivo bromodeoxyuridine (BrdU) immunohistochemistry for assessment of human colonic cell proliferation. From 16 subjects without colonic disease biopsy specimens were collected from five different sites along the colorectum and processed for BrdU and PCNA immunohistochemistry. The mean proliferation index of PCNA was significantly higher at 133% of the value obtained with BrdU. There was, however, a good correlation between the results from both techniques (r = 0.6275; p < 0.05). Decrease in proliferation index along the colorectum was seen with both staining methods but was clearer with PCNA immunohistochemistry (caecum/ascending colon v rectum: 12.0 v 7.2; p < 0.004). The total number of crypt cells also decreased from proximal to distal (134 to 128; p < 0.06) but at no site correlated significantly with the proliferation index. It is concluded that in clinical cell kinetic studies staining for PCNA may serve as an attractive alternative to the BrdU incorporation assay. Images Figure 4 PMID:7909785

  20. Aberrant epithelial GREM1 expression initiates colonic tumorigenesis from cells outside of the crypt base stem cell niche

    PubMed Central

    Bansal, Mukesh; Rafferty, Hannah; Boitsova, Tatjana; Bardella, Chiara; Jaeger, Emma; Lewis, Annabelle; Freeman-Mills, Luke; Giner, Francesc Castro; Rodenas-Cuadrado, Pedro; Mallappa, Sreelakshmi; Clark, Susan; Thomas, Huw; Jeffery, Rosemary; Poulsom, Richard; Rodriguez-Justo, Manuel; Novelli, Marco; Chetty, Runjan; Silver, Andrew; Sansom, Owen James; Greten, Florian R; Wang, Lai Mun; East, James Edward; Tomlinson, Ian; Leedham, Simon John

    2015-01-01

    Hereditary mixed polyposis syndrome (HMPS) is characterised by the development of mixed morphology colorectal tumours and is caused by a 40 kb duplication that results in aberrant epithelial expression of the mesenchymal Bone Morphogenetic Protein antagonist, GREM1. Here we use HMPS tissue and a mouse model of the disease to show that epithelial GREM1 disrupts homeostatic intestinal morphogen gradients, altering cell-fate, that is normally determined by position along the vertical epithelial axis. This promotes the persistence and/or reacquisition of stem-cell properties in Lgr5 negative (non-expressing) progenitor cells that have exited the stem-cell niche. These cells form ectopic crypts, proliferate, accumulate somatic mutations and can initiate intestinal neoplasia, indicating that the crypt base stem-cell is not the sole cell-of-origin of colorectal cancer. Furthermore, we show that epithelial expression of GREM1 also occurs in traditional serrated adenomas, sporadic pre-malignant lesions with a hitherto unknown pathogenesis and these lesions can be considered the sporadic equivalents of HMPS polyps. PMID:25419707

  1. 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.

  2. Correction of cell-induced optical aberrations in a fluorescence fluctuation microscope

    PubMed Central

    Leroux, Charles-Edouard; Grichine, Alexei; Wang, Irène; Delon, Antoine

    2013-01-01

    We describe the effect of optical aberrations on fluorescence fluctuations microscopy (FFM), when focusing through a single living cell. FFM measurements are performed in an aqueous fluorescent solution, and prove to be a highly sensitive tool to assess the optical aberrations introduced by the cell. We demonstrate an adaptive optics (AO) system to remove the aberration-related bias in the FFM measurements. Our data show that AO is not only useful when imaging deep in tissues, but also when performing FFM measurements through a single cellular layer. PMID:23939061

  3. Inhibitor of striate conditionally suppresses cell proliferation in variegated maize

    PubMed Central

    Park, Sung Han; Park, Su Hyun; Chin, Hang Gyeong; Cho, Moo Je; Martienssen, Robert A.; Han, Chang-deok

    2000-01-01

    Since the work done by R.A. Emerson in the 1930s, Inhibitor of striate (Isr) has been recognized as a dose-dependent genetic modifier of variegation in chlorotic leaf striping mutants of maize such as striate2 (sr2). We have shown that Isr specifically inhibits proliferation and differentiation of plastid defective cells in sr2 mutants. Leaf narrowing is due to loss of intermediate veins and ground tissue located at leaf margins, and the few remaining plastid defective cells are of irregular size and aberrant organization. The Isr gene has been cloned by targeted transposon tagging. Isr mRNA is expressed throughout young leaves, but Isr chimeras indicate that the expression of Isr at leaf margins is sufficient to suppress both the lateral expansion of sr2 leaves and the extent of striping. Isr protein appears to encode a chloroplast protein with sequence similarity to a family of bacterial phosphatases involved in carbon catabolite repression or in carbon metabolism. We propose that the action of Isr in nuclear and plastid communication could be triggered by carbon stress. PMID:10783171

  4. The Distribution of Chromosomal Aberrations in Human Cells Predicted by a Generalized Time-Dependent Model of Radiation-Induced Formation of Aberrations

    NASA Technical Reports Server (NTRS)

    Ponomarev, Artem L.; George, K.; Cucinotta, F. A.

    2011-01-01

    New experimental data show how chromosomal aberrations for low- and high-LET radiation are dependent on DSB repair deficiencies in wild-type, AT and NBS cells. We simulated the development of chromosomal aberrations in these cells lines in a stochastic track-structure-dependent model, in which different cells have different kinetics of DSB repair. We updated a previously formulated model of chromosomal aberrations, which was based on a stochastic Monte Carlo approach, to consider the time-dependence of DSB rejoining. The previous version of the model had an assumption that all DSBs would rejoin, and therefore we called it a time-independent model. The chromosomal-aberrations model takes into account the DNA and track structure for low- and high-LET radiations, and provides an explanation and prediction of the statistics of rare and more complex aberrations. We compared the program-simulated kinetics of DSB rejoining to the experimentally-derived bimodal exponential curves of the DSB kinetics. We scored the formation of translocations, dicentrics, acentric and centric rings, deletions, and inversions. The fraction of DSBs participating in aberrations was studied in relation to the rejoining time. Comparisons of simulated dose dependence for simple aberrations to the experimental dose-dependence for HF19, AT and NBS cells will be made.

  5. Mesenchymal precursor cells maintain the differentiation and proliferation potentials of breast epithelial cells

    PubMed Central

    2014-01-01

    Introduction Stromal-epithelial interactions play a fundamental role in tissue homeostasis, controlling cell proliferation and differentiation. Not surprisingly, aberrant stromal-epithelial interactions contribute to malignancies. Studies of the cellular and molecular mechanisms underlying these interactions require ex vivo experimental model systems that recapitulate the complexity of human tissue without compromising the differentiation and proliferation potentials of human primary cells. Methods We isolated and characterized human breast epithelial and mesenchymal precursors from reduction mammoplasty tissue and tagged them with lentiviral vectors. We assembled heterotypic co-cultures and compared mesenchymal and epithelial cells to cells in corresponding monocultures by analyzing growth, differentiation potentials, and gene expression profiles. Results We show that heterotypic culture of non-immortalized human primary breast epithelial and mesenchymal precursors maintains their proliferation and differentiation potentials and constrains their growth. We further describe the gene expression profiles of stromal and epithelial cells in co-cultures and monocultures and show increased expression of the tumor growth factor beta (TGFβ) family member inhibin beta A (INHBA) in mesenchymal cells grown as co-cultures compared with monocultures. Notably, overexpression of INHBA in mesenchymal cells increases colony formation potential of epithelial cells, suggesting that it contributes to the dynamic reciprocity between breast mesenchymal and epithelial cells. Conclusions The described heterotypic co-culture system will prove useful for further characterization of the molecular mechanisms mediating interactions between human normal or neoplastic breast epithelial cells and the stroma, and will provide a framework to test the relevance of the ever-increasing number of oncogenomic alterations identified in human breast cancer. PMID:24916766

  6. Osteosarcoma cells induce endothelial cell proliferation during neo-angiogenesis.

    PubMed

    de Nigris, Filomena; Mancini, Francesco Paolo; Schiano, Concetta; Infante, Teresa; Zullo, Alberto; Minucci, Pellegrino Biagio; Al-Omran, Mohammed; Giordano, Antonio; Napoli, Claudio

    2013-04-01

    Understanding the mechanisms inducing endothelial cell (EC) proliferation following tumor microenvironment stimuli may be important for the development of antiangiogenic therapies. Here, we show that cyclin-dependent kinase 2 and 5 (Cdk2, Cdk5) are important mediators of neoangiogenesis in in vitro and in vivo systems. Furthermore, we demonstrate that a specific Yin Yang 1 (YY1) protein-dependent signal from osteosarcoma (SaOS) cells determines proliferation of human aortic endothelial cells (HAECs). Following tumor cell stimuli, HAECs overexpress Cdk2 and Cdk5, display increased Cdk2 activity, undergo enhanced proliferation, and form capillary-like structures. Moreover, Roscovitine, an inhibitor of Cdks, blunted overexpression of Cdk2 and Cdk5 and Cdk2 activity induced by the YY1-dependent signal secreted by SaOS cells. Furthermore, Roscovitine decreased HAEC proliferation and angiogenesis (the latter by 70% in in vitro and 50% in in vivo systems; P < 0.01 vs. control). Finally, the finding that Roscovitine triggers apoptosis in SaOS cells as well as in HAECs by activating caspase-3/7 indicates multiple mechanisms for the potential antitumoral effect of Roscovitine. Present work suggests that Cdk2 and Cdk5 might be pharmacologically accessible targets for both antiangiogenic and antitumor therapy. Copyright © 2012 Wiley Periodicals, Inc.

  7. Painting Analysis of Chromosome Aberrations Induced by Energetic Heavy Ions in Human Cells

    NASA Technical Reports Server (NTRS)

    Wu, Honglu

    2006-01-01

    FISH, mFISH, mBAND, telomere and centromere probes have been used to study chromosome aberrations induced in human cells exposed to low-and high-LET radiation in vitro. High-LET induced damages are mostly a single track effect. Unrejoined chromosome breaks (incomplete exchanges) and complex type aberrations were higher for high-LET. Biosignatures may depend on the method the samples are collected. Recent mBAND analysis has revealed more information about the nature of intra-chromosome exchanges. Whether space flight/microgravity affects radiation-induced chromosome aberration frequencies is still an open question.

  8. 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

  9. Cell Proliferation, Reactive Oxygen and Cellular Glutathione

    PubMed Central

    Day, Regina M.; Suzuki, Yuichiro J.

    2005-01-01

    A variety of cellular activities, including metabolism, growth, and death, are regulated and modulated by the redox status of the environment. A biphasic effect has been demonstrated on cellular proliferation with reactive oxygen species (ROS)—especially hydrogen peroxide and superoxide—in which low levels (usually submicromolar concentrations) induce growth but higher concentrations (usually >10–30 micromolar) induce apoptosis or necrosis. This phenomenon has been demonstrated for primary, immortalized and transformed cell types. However, the mechanism of the proliferative response to low levels of ROS is not well understood. Much of the work examining the signal transduction by ROS, including H2O2, has been performed using doses in the lethal range. Although use of higher ROS doses have allowed the identification of important signal transduction pathways, these pathways may be activated by cells only in association with ROS-induced apoptosis and necrosis, and may not utilize the same pathways activated by lower doses of ROS associated with increased cell growth. Recent data has shown that low levels of exogenous H2O2 up-regulate intracellular glutathione and activate the DNA binding activity toward antioxidant response element. The modulation of the cellular redox environment, through the regulation of cellular glutathione levels, may be a part of the hormetic effect shown by ROS on cell growth. PMID:18648617

  10. MET inhibitor PHA-665752 suppresses the hepatocyte growth factor-induced cell proliferation and radioresistance in nasopharyngeal carcinoma cells

    SciTech Connect

    Liu, Tongxin; Li, Qi; Sun, Quanquan

    2014-06-20

    Highlights: • We demonstrated that irradiation induced MET overexpression and activation. • The aberrant MET signal mediated by HGF induced proliferation and radioresistance of NPC cells. • MET inhibitor PHA-665752 effectively suppressed HGF induced cell proliferation and radioresistance in NPC cells. • PHA-665752 suppressed the three downstream pathway of HGF/MET signal in a dose-dependent manner. - Abstract: Although ionizing radiation (IR) has provided considerable improvements in nasopharyngeal carcinoma (NPC), in subsets of patients, radioresistance is still a major problem in the treatment. In this study, we demonstrated that irradiation induced MET overexpression and activation, and the aberrant MET signal mediatedmore » by hepatocyte growth factor (HGF) induced radioresistance. We also found that MET inhibitor PHA-665752 effectively suppressed HGF induced cell proliferation and radioresistance in NPC cells. Further investigation indicated that PHA-665752 suppressed the phosphorylation of the Akt, ERK1/2, and STAT3 proteins in a dose-dependent manner. Our data indicated that the combination of IR with a MET inhibitor, such as PHA-665752, might be a promising therapeutic strategy for NPC.« less

  11. WWC3 Inhibits Glioma Cell Proliferation Through Suppressing the Wnt/β-Catenin Signaling Pathway.

    PubMed

    Wang, Yanni; Jiang, Man; Yao, Yongshan; Cai, Zhengwei

    2018-01-01

    The scaffolding protein WW and C2 domain-containing protein 3 (WWC3) belonging to the WWC protein family plays important roles in regulating cell proliferation, cell migration, and synaptic signaling. The critical role of WWC3 in tumorigenesis has emerged recently; however, the expression and function of WWC3 in glioma remain largely unknown. Here, we found that WWC3 was significantly downregulated in glioma tissues and cell lines. Overexpression of WWC3 inhibited the glioma cell proliferation, migration, and invasion. Depletion of WWC3 promoted the proliferation of glioma cells. Mechanistically, we found that overexpression of WWC3 suppressed the activity of β-catenin, the signaling that tightly associates with cell proliferation and growth. Depletion of WWC3 enhanced the activity of β-catenin/Wnt signaling. Further investigation demonstrated that WWC3 interacted with T cell factor 4 (TCF4), an identified associated binding partner of β-catenin. The interaction between WWC3 and TCF4 might inhibit the transcriptional activation of β-catenin. Our results provide novel insights into the aberrant expression and molecular mechanism of WWC3 in glioma, which indicated WWC3 as a potential target for clinical intervention in glioma.

  12. Ectopic Activation of Wnt/β-Catenin Signaling in Lens Fiber Cells Results in Cataract Formation and Aberrant Fiber Cell Differentiation

    PubMed Central

    Antosova, Barbora; Smolikova, Jana; Borkovcova, Romana; Strnad, Hynek; Lachova, Jitka; Machon, Ondrej; Kozmik, Zbynek

    2013-01-01

    The Wnt/β-catenin signaling pathway controls many processes during development, including cell proliferation, cell differentiation and tissue homeostasis, and its aberrant regulation has been linked to various pathologies. In this study we investigated the effect of ectopic activation of Wnt/β-catenin signaling during lens fiber cell differentiation. To activate Wnt/β-catenin signaling in lens fiber cells, the transgenic mouse referred to as αA-CLEF was generated, in which the transactivation domain of β-catenin was fused to the DNA-binding protein LEF1, and expression of the transgene was controlled by αA-crystallin promoter. Constitutive activation of Wnt/β-catenin signaling in lens fiber cells of αA-CLEF mice resulted in abnormal and delayed fiber cell differentiation. Moreover, adult αA-CLEF mice developed cataract, microphthalmia and manifested downregulated levels of γ-crystallins in lenses. We provide evidence of aberrant expression of cell cycle regulators in embryonic lenses of αA-CLEF transgenic mice resulting in the delay in cell cycle exit and in the shift of fiber cell differentiation to the central fiber cell compartment. Our results indicate that precise regulation of the Wnt/β-catenin signaling activity during later stages of lens development is essential for proper lens fiber cell differentiation and lens transparency. PMID:24205179

  13. TNFRSF14 aberrations in follicular lymphoma increase clinically significant allogeneic T-cell responses.

    PubMed

    Kotsiou, Eleni; Okosun, Jessica; Besley, Caroline; Iqbal, Sameena; Matthews, Janet; Fitzgibbon, Jude; Gribben, John G; Davies, Jeffrey K

    2016-07-07

    Donor T-cell immune responses can eradicate lymphomas after allogeneic hematopoietic stem cell transplantation (AHSCT), but can also damage healthy tissues resulting in harmful graft-versus-host disease (GVHD). Next-generation sequencing has recently identified many new genetic lesions in follicular lymphoma (FL). One such gene, tumor necrosis factor receptor superfamily 14 (TNFRSF14), abnormal in 40% of FL patients, encodes the herpes virus entry mediator (HVEM) which limits T-cell activation via ligation of the B- and T-lymphocyte attenuator. As lymphoma B cells can act as antigen-presenting cells, we hypothesized that TNFRSF14 aberrations that reduce HVEM expression could alter the capacity of FL B cells to stimulate allogeneic T-cell responses and impact the outcome of AHSCT. In an in vitro model of alloreactivity, human lymphoma B cells with TNFRSF14 aberrations had reduced HVEM expression and greater alloantigen-presenting capacity than wild-type lymphoma B cells. The increased immune-stimulatory capacity of lymphoma B cells with TNFRSF14 aberrations had clinical relevance, associating with higher incidence of acute GVHD in patients undergoing AHSCT. FL patients with TNFRSF14 aberrations may benefit from more aggressive immunosuppression to reduce harmful GVHD after transplantation. Importantly, this study is the first to demonstrate the impact of an acquired genetic lesion on the capacity of tumor cells to stimulate allogeneic T-cell immune responses which may have wider consequences for adoptive immunotherapy strategies. © 2016 by The American Society of Hematology.

  14. Uterine epithelial cell proliferation and endometrial hyperplasia: evidence from a mouse model.

    PubMed

    Gao, Yang; Li, Shu; Li, Qinglei

    2014-08-01

    In the uterus, epithelial cell proliferation changes during the estrous cycle and pregnancy. Uncontrolled epithelial cell proliferation results in implantation failure and/or cancer development. Transforming growth factor-β (TGF-β) signaling is a fundamental regulator of diverse biological processes and is indispensable for multiple reproductive functions. However, the in vivo role of TGF-β signaling in uterine epithelial cells remains poorly defined. We have shown that in the uterus, conditional deletion of the Type 1 receptor for TGF-β (Tgfbr1) using anti-Müllerian hormone receptor type 2 (Amhr2) Cre leads to myometrial defects. Here, we describe enhanced epithelial cell proliferation by immunostaining of Ki67 in the uteri of these mice. The aberration culminated in endometrial hyperplasia in aged females. To exclude the potential influence of ovarian steroid hormones, the proliferative status of uterine epithelial cells was assessed following ovariectomy. Increased uterine epithelial cell proliferation was also revealed in ovariectomized Tgfbr1 Amhr2-Cre conditional knockout mice. We further demonstrated that transcript levels for fibroblast growth factor 10 (Fgf10) were markedly up-regulated in Tgfbr1 Amhr2-Cre conditional knockout uteri. Consistently, treatment of primary uterine stromal cells with TGF-β1 significantly reduced Fgf10 mRNA expression. Thus, our findings suggest a potential involvement of TGFBR1-mediated signaling in the regulation of uterine epithelial cell proliferation, and provide genetic evidence supporting the role of uterine epithelial cell proliferation in the pathogenesis of endometrial hyperplasia. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. 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.

  16. Expression and Function of the Progesterone Receptor in Human Prostate Stroma Provide Novel Insights to Cell Proliferation Control

    PubMed Central

    Yu, Yue; Liu, Liangliang; Xie, Ning; Xue, Hui; Fazli, Ladan; Buttyan, Ralph; Wang, Yuzhuo; Gleave, Martin

    2013-01-01

    Context: Like other tissues, the prostate is an admixture of many different cell types that can be segregated into components of the epithelium or stroma. Reciprocal interactions between these 2 types of cells are critical for maintaining prostate homeostasis, whereas aberrant stromal cell proliferation can disrupt this balance and result in diseases such as benign prostatic hyperplasia. Although the androgen and estrogen receptors are relatively well studied for their functions in controlling stromal cell proliferation and differentiation, the role of the progesterone receptor (PR) remains unclear. Objective: The aim of the study was to investigate the expression and function of the PR in the prostate. Design and Setting: Human prostate biopsies, renal capsule xenografts, and prostate stromal cells were used. Immunohistochemistry, Western blotting, real-time quantitative PCR, cell proliferation, flow cytometry, and gene microarray analyses were performed. Results: Two PR isoforms, PRA and PRB, are expressed in prostate stromal fibroblasts and smooth muscle cells, but not in epithelial cells. Both PR isoforms suppress prostate stromal cell proliferation through inhibition of the expression of cyclinA, cyclinB, and cdc25c, thus delaying cell cycling through S and M phases. Gene microarray analyses further demonstrated that PRA and PRB regulated different transcriptomes. However, one of the major gene groups commonly regulated by both PR isoforms was the one associated with regulation of cell proliferation. Conclusion: PR plays an inhibitory role in prostate stromal cell proliferation. PMID:23666965

  17. Phenotypic characterization of aberrant stem and progenitor cell populations in myelodysplastic syndromes.

    PubMed

    Ostendorf, Benjamin N; Flenner, Eva; Flörcken, Anne; Westermann, Jörg

    2018-01-01

    Recent reports have revealed myelodysplastic syndromes (MDS) to arise from cancer stem cells phenotypically similar to physiological hematopoietic stem cells. Myelodysplastic hematopoiesis maintains a hierarchical organization, but the proportion of several hematopoietic compartments is skewed and multiple surface markers are aberrantly expressed. These aberrant antigen expression patterns hold diagnostic and therapeutic promise. However, eradication of MDS requires targeting of early myelodysplasia propagating stem cells. This warrants an exact assessment of the differentiation stage at which aberrant expression occurs in transformed hematopoiesis. Here, we report results on the prospective and extensive dissection of the hematopoietic hierarchy in 20 patients with either low-risk MDS or MDS with excess blasts and compare it to hematopoiesis in patients with non-malignancy-associated cytopenia or B cell lymphoma without bone marrow infiltration. We found patients with MDS with excess blasts to exhibit characteristic expansions of specific immature progenitor compartments. We also identified the aberrant expression of several markers including ALDH, CLL-1, CD44, and CD47 to be specific features of hematopoiesis in MDS with excess blasts. We show that amongst these, aberrant CLL-1 expression manifested at the early uncommitted hematopoietic stem cell level, suggesting a potential role as a therapeutic target.

  18. Satellite cell proliferation in adult skeletal muscle

    NASA Technical Reports Server (NTRS)

    Morrison, Paul R. (Inventor); Thomason, Donald B. (Inventor); Stancel, George M. (Inventor); Booth, Frank W. (Inventor)

    1995-01-01

    Novel methods of retroviral-mediated gene transfer for the in vivo corporation and stable expression of eukaryotic or prokaryotic foreign genes in tissues of living animals is described. More specifically, methods of incorporating foreign genes into mitotically active cells are disclosed. The constitutive and stable expression of E. coli .beta.-galactosidase gene under the promoter control of the Moloney murine leukemia virus long terminal repeat is employed as a particularly preferred embodiment, by way of example, establishes the model upon which the incorporation of a foreign gene into a mitotically-active living eukaryotic tissue is based. Use of the described methods in therapeutic treatments for genetic diseases, such as those muscular degenerative diseases, is also presented. In muscle tissue, the described processes result in genetically-altered satellite cells which proliferate daughter myoblasts which preferentially fuse to form a single undamaged muscle fiber replacing damaged muscle tissue in a treated animal. The retroviral vector, by way of example, includes a dystrophin gene construct for use in treating muscular dystrophy. The present invention also comprises an experimental model utilizable in the study of the physiological regulation of skeletal muscle gene expression in intact animals.

  19. Dual effect of LPS on murine myeloid leukemia cells: Pro-proliferation and anti-proliferation

    SciTech Connect

    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

  20. Sall4 is essential for stabilization, but not for pluripotency, of embryonic stem cells by repressing aberrant trophectoderm gene expression.

    PubMed

    Yuri, Shunsuke; Fujimura, Sayoko; Nimura, Keisuke; Takeda, Naoki; Toyooka, Yayoi; Fujimura, Yu-Ichi; Aburatani, Hiroyuki; Ura, Kiyoe; Koseki, Haruhiko; Niwa, Hitoshi; Nishinakamura, Ryuichi

    2009-04-01

    Sall4 is a mouse homolog of a causative gene of the autosomal dominant disorder Okihiro syndrome. We previously showed that the absence of Sall4 leads to lethality during peri-implantation and that Sall4-null embryonic stem (ES) cells proliferate poorly with intact pluripotency when cultured on feeder cells. Here, we report that, in the absence of feeder cells, Sall4-null ES cells express the trophectoderm marker Cdx2, but are maintained for a long period in an undifferentiated state with minimally affected Oct3/4 expression. Feeder-free Sall4-null ES cells contribute solely to the inner cell mass and epiblast in vivo, indicating that these cells still retain pluripotency and do not fully commit to the trophectoderm. These phenotypes could arise from derepression of the Cdx2 promoter, which is normally suppressed by Sall4 and the Mi2/NuRD HDAC complex. However, proliferation was impaired and G1 phase prolonged in the absence of Sall4, suggesting another role for Sall4 in cell cycle control. Although Sall1, also a Sall family gene, is known to genetically interact with Sall4 in vivo, Sall1-null ES cells have no apparent defects and no exacerbation is observed in ES cells lacking both Sall1 and Sall4, compared with Sall4-null cells. This suggests a unique role for Sall4 in ES cells. Thus, though Sall4 does not contribute to the central machinery of the pluripotency, it stabilizes ES cells by repressing aberrant trophectoderm gene expression.

  1. Intestinal Cell Proliferation and Senescence Are Regulated by Receptor Guanylyl Cyclase C and p21*

    PubMed Central

    Basu, Nirmalya; Saha, Sayanti; Khan, Imran; Ramachandra, Subbaraya G.; Visweswariah, Sandhya S.

    2014-01-01

    Guanylyl cyclase C (GC-C) is expressed in intestinal epithelial cells and serves as the receptor for bacterial heat-stable enterotoxin (ST) peptides and the guanylin family of gastrointestinal hormones. Activation of GC-C elevates intracellular cGMP, which modulates intestinal fluid-ion homeostasis and differentiation of enterocytes along the crypt-villus axis. GC-C activity can regulate colonic cell proliferation by inducing cell cycle arrest, and mice lacking GC-C display increased cell proliferation in colonic crypts. Activation of GC-C by administration of ST to wild type, but not Gucy2c−/−, mice resulted in a reduction in carcinogen-induced aberrant crypt foci formation. In p53-deficient human colorectal carcinoma cells, ST led to a transcriptional up-regulation of p21, the cell cycle inhibitor, via activation of the cGMP-responsive kinase PKGII and p38 MAPK. Prolonged treatment of human colonic carcinoma cells with ST led to nuclear accumulation of p21, resulting in cellular senescence and reduced tumorigenic potential. Our results, therefore, identify downstream effectors for GC-C that contribute to regulating intestinal cell proliferation. Thus, genomic responses to a bacterial toxin can influence intestinal neoplasia and senescence. PMID:24217248

  2. Chromosome aberrations and cell death by ionizing radiation: Evolution of a biophysical model

    NASA Astrophysics Data System (ADS)

    Ballarini, Francesca; Carante, Mario P.

    2016-11-01

    The manuscript summarizes and discusses the various versions of a radiation damage biophysical model, implemented as a Monte Carlo simulation code, originally developed for chromosome aberrations and subsequently extended to cell death. This extended version has been called BIANCA (BIophysical ANalysis of Cell death and chromosome Aberrations). According to the basic assumptions, complex double-strand breaks (called ;Cluster Lesions;, or CLs) produce independent chromosome free-ends, mis-rejoining within a threshold distance d (or un-rejoining) leads to chromosome aberrations, and ;lethal aberrations; (i.e., dicentrics plus rings plus large deletions) lead to clonogenic cell death. The mean number of CLs per Gy and per cell is an adjustable parameter. While in BIANCA the threshold distance d was the second parameter, in a subsequent version, called BIANCA II, d has been fixed as the mean distance between two adjacent interphase chromosome territories, and a new parameter, f, has been introduced to represent the chromosome free-end un-rejoining probability. Simulated dose-response curves for chromosome aberrations and cell survival obtained by the various model versions were compared with literature experimental data. Such comparisons provided indications on some open questions, including the role of energy deposition clustering at the nm and the μm level, the probability for a chromosome free-end to remain un-rejoined, and the relationship between chromosome aberrations and cell death. Although both BIANCA and BIANCA II provided cell survival curves in general agreement with human and hamster fibroblast survival data, BIANCA II allowed for a better reproduction of dicentrics, rings and deletions considered separately. Furthermore, the approach adopted in BIANCA II for d is more consistent with estimates reported in the literature. After testing against aberration and survival data, BIANCA II was applied to investigate the depth-dependence of the radiation

  3. Osthole inhibits proliferation and induces apoptosis in human osteosarcoma cells.

    PubMed

    Ding, Yong; Lu, Xiongwei; Hu, Xiaopeng; Ma, Jie; Ding, Huan

    2014-02-01

    The purpose of this study was to investigate the effect of osthole on osteosarcoma cell proliferation and apoptosis. Cell counting Kit-8 assay was performed to establish the effects of osthole on osteosarcoma MG-63 cell proliferation. Annexin V-FITC/PI was performed to analyze the apoptotic rate of the cells. The inhibitory effects of osthole on the expression of BCL-2, BAX, and caspase-3 were detected by Western blotting. Osthole inhibited the growth of human osteosarcoma MG-63 cells by inhibiting cell proliferation and induced cell apoptosis. Western blotting demonstrated that osthole downregulated the expressions of BCL-2 and caspase-3 and upregulated the expression of BAX in human osteosarcoma cells. Osthole can inhibit osteosarcoma cell proliferation and induced apoptosis effectively in a dose-dependent manner through downregulating the expression of BCL-2 and caspase-3 proteins levels and upregulating the expression of BAX proteins levels.

  4. 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

  5. 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

  6. Haematopoietic ESL-1 enables stem cell proliferation in the bone marrow by limiting TGFβ availability.

    PubMed

    Leiva, Magdalena; Quintana, Juan A; Ligos, José M; Hidalgo, Andrés

    2016-01-08

    The life-long maintenance of haematopoietic stem and progenitor cells (HSPCs) critically relies on environmental signals produced by cells that constitute the haematopoietic niche. Here we report a cell-intrinsic mechanism whereby haematopoietic cells limit proliferation within the bone marrow, and show that this pathway is repressed by E-selectin ligand 1 (ESL-1). Mice deficient in ESL-1 display aberrant HSPC quiescence, expansion of the immature pool and reduction in niche size. Remarkably, the traits were transplantable and dominant when mutant and wild-type precursors coexisted in the same environment, but were independent of E-selectin, the vascular receptor for ESL-1. Instead, quiescence is generated by unrestrained production of the cytokine TGFβ by mutant HSPC, and in vivo or in vitro blockade of the cytokine completely restores the homeostatic properties of the haematopoietic niche. These findings reveal that haematopoietic cells, including the more primitive compartment, can actively shape their own environment.

  7. Haematopoietic ESL-1 enables stem cell proliferation in the bone marrow by limiting TGFβ availability

    PubMed Central

    Leiva, Magdalena; Quintana, Juan A.; Ligos, José M.; Hidalgo, Andrés

    2016-01-01

    The life-long maintenance of haematopoietic stem and progenitor cells (HSPCs) critically relies on environmental signals produced by cells that constitute the haematopoietic niche. Here we report a cell-intrinsic mechanism whereby haematopoietic cells limit proliferation within the bone marrow, and show that this pathway is repressed by E-selectin ligand 1 (ESL-1). Mice deficient in ESL-1 display aberrant HSPC quiescence, expansion of the immature pool and reduction in niche size. Remarkably, the traits were transplantable and dominant when mutant and wild-type precursors coexisted in the same environment, but were independent of E-selectin, the vascular receptor for ESL-1. Instead, quiescence is generated by unrestrained production of the cytokine TGFβ by mutant HSPC, and in vivo or in vitro blockade of the cytokine completely restores the homeostatic properties of the haematopoietic niche. These findings reveal that haematopoietic cells, including the more primitive compartment, can actively shape their own environment. PMID:26742601

  8. Silencing of Urothelial Carcinoma Associated 1 Inhibits the Proliferation and Migration of Medulloblastoma Cells.

    PubMed

    Zhengyuan, Xie; Hu, Xiao; Qiang, Wang; Nanxiang, Li; Junbin, Cai; Wangming, Zhang

    2017-09-16

    BACKGROUND UCA1 is a long non-coding RNA that has been found to be aberrantly upregulated in various cancers. The aim of this study was to determine the expression level and function of UCA1 in medulloblastoma, the most common malignant brain tumor during childhood. MATERIAL AND METHODS Real-time PCR was used to detect the expression of UCA1 in medulloblastoma specimens and cell lines. Lentiviral-mediated expression of a short hairpin RNA (shRNA) targeting UCA1 or a negative control shRNA was also achieved with the medulloblastoma cell line, Daoy. Cell proliferation and cell cycle progression were subsequently characterized with cell counting kit (CCK)-8 and flow cytometry. Cell migration was examined in wound healing and Transwell migration assays. RESULTS Levels of UCA1 mRNA were higher in the medulloblastoma specimens (p<0.05) and cell lines (p<0.05) compared to the corresponding nontumor adjacent tissue specimens and a glioblastoma cell line, respectively. For the Daoy cells with silenced UCA1, their proliferation was reduced by 30% compared to the Daoy cells expressing a negative control shRNA (p=0.017). Cell cycle arrest in the G0/G1 phase, resulting in a decreased number of cells in the S phase, as well as reduced cell migration in both wound scratch healing (p=0.001) and Transwell migration assays (p=0.021) were also observed for the Daoy cells with silenced UCA1. CONCLUSIONS UCA1 was highly expressed in part of medulloblastoma specimens and cell lines examined. In addition, knockdown of UCA1 significantly inhibited the proliferation and migration of medulloblastoma cells in vitro.

  9. Hippocampal cell proliferation regulation by repeated stress and antidepressants.

    PubMed

    Chen, Hu; Pandey, Ghanshyam N; Dwivedi, Yogesh

    2006-06-26

    A recent hypothesis suggests reduced hippocampal neurogenesis in depression. Here, we examined cell proliferation in the dentate gyrus and the subventricular zone of rats given repeated stress, a paradigm that prolongs learned helplessness behavior, and whether antidepressants modulate the learned helplessness-associated altered cell proliferation. Decreased cell proliferation, number of clusters, and cells/cluster were noted in the dentate gyrus, but not in the subventricular zone, of learned helplessness rats. Both fluoxetine and desipramine reversed the learned helplessness behavior and increased the cell proliferation and the number of clusters in learned helplessness rats; only fluoxetine did so significantly. Both fluoxetine and desipramine significantly increased the number of cells/cluster. Our results suggest modified hippocampal neurogenesis in prolonged depression and in the mechanism of antidepressant action.

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

    PubMed Central

    Mehdi, Ali; Riazalhosseini, Yasser

    2017-01-01

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

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

    PubMed

    Mehdi, Ali; Riazalhosseini, Yasser

    2017-08-16

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

  12. Splicing factors PTBP1 and PTBP2 promote proliferation and migration of glioma cell lines

    PubMed Central

    Cheung, Hannah C.; Hai, Tao; Zhu, Wen; Baggerly, Keith A.; Tsavachidis, Spiridon; Krahe, Ralf

    2009-01-01

    Polypyrimidine tract-binding protein 1 (PTBP1) is a multi-functional RNA-binding protein that is aberrantly overexpressed in glioma. PTBP1 and its brain-specific homologue polypyrimidine tract-binding protein 2 (PTBP2) regulate neural precursor cell differentiation. However, the overlapping and non-overlapping target transcripts involved in this process are still unclear. To determine why PTBP1 and not PTBP2 would promote glial cell-derived tumours, both PTBP1 and PTBP2 were knocked down in the human glioma cell lines U251 and LN229 to determine the role of these proteins in cell proliferation, migration, and adhesion. Surprisingly, removal of both PTBP1 and PTBP2 slowed cell proliferation, with the double knockdown having no additive effects. Decreased expression of both proteins individually and in combination inhibited cell migration and increased adhesion of cells to fibronectin and vitronectin. A global survey of differential exon expression was performed following PTBP1 knockdown in U251 cells using the Affymetrix Exon Array to identify PTBP1-specific splicing targets that enhance gliomagenesis. In the PTBP1 knockdown, previously determined targets were unaltered in their splicing patterns. A single gene, RTN4 (Nogo) had significantly enhanced inclusion of exon 3 when PTBP1 was removed. Overexpression of the splice isoform containing exon 3 decreased cell proliferation to a similar degree as the removal of PTBP1. These results provide the first evidence that RNA-binding proteins affect the invasive and rapid growth characteristics of glioma cell lines. Its actions on proliferation appear to be mediated, in part, through alternative splicing of RTN4. PMID:19506066

  13. Persistence of radiation-induced chromosome aberrations in a long-term cell culture.

    PubMed

    Duran, Assumpta; Barquinero, Joan Francesc; Caballín, María Rosa; Ribas, Montserrat; Barrios, Leonardo

    2009-04-01

    The aim of the present study was to evaluate the persistence of chromosome aberrations induced by X rays. FISH painting and mFISH techniques were applied to long-term cultures of irradiated cells. With painting, at 2 Gy the frequency of apparently simple translocations remained almost invariable during all the culture, whereas at 4 Gy a rapid decline was observed between the first and the second samples, followed by a slight decrease until the end of the culture. Apparently simple dicentrics and complex aberrations disappeared after the first sample at 2 and 4 Gy. By mFISH, at 2 Gy the frequency of complete plus one-way translocations remained invariable between the first and last sample, but at 4 Gy a 60% decline was observed. True incomplete simple translocations disappeared at 2 and 4 Gy, indicating that incompleteness could be a factor to consider when the persistence of translocations is analyzed. The analysis by mFISH showed that the frequency of complex aberrations and their complexity increased with dose and tended to disappear in the last sample. Our results indicate that the influence of dose on the decrease in the frequency of simple translocations with time postirradiation cannot be fully explained by the disappearance of true incomplete translocations and complex aberrations. The chromosome involvement was random for radiation-induced exchange aberrations and non-random for total aberrations. Chromosome 7 showed the highest deviations from expected, being less and more involved than expected in the first and last samples, respectively. Some preferential chromosome-chromosome associations were observed, including a coincidence with a cluster from radiogenic chromosome aberrations described in other studies.

  14. Zinc oxide nanoparticles as selective killers of proliferating cells

    PubMed Central

    Taccola, Liuba; Raffa, Vittoria; Riggio, Cristina; Vittorio, Orazio; Iorio, Maria Carla; Vanacore, Renato; Pietrabissa, Andrea; Cuschieri, Alfred

    2011-01-01

    Background: It has recently been demonstrated that zinc oxide nanoparticles (ZnO NPs) induce death of cancerous cells whilst having no cytotoxic effect on normal cells. However, there are several issues which need to be resolved before translation of zinc oxide nanoparticles into medical use, including lack of suitable biocompatible dispersion protocols and a better understanding being needed of the mechanism of their selective cytotoxic action. Methods: Nanoparticle dose affecting cell viability was evaluated in a model of proliferating cells both experimentally and mathematically. The key issue of selective toxicity of ZnO NPs toward proliferating cells was addressed by experiments using a biological model of noncancerous cells, ie, mesenchymal stem cells before and after cell differentiation to the osteogenic lineage. Results: In this paper, we report a biocompatible protocol for preparation of stable aqueous solutions of monodispersed zinc oxide nanoparticles. We found that the threshold of intracellular ZnO NP concentration required to induce cell death in proliferating cells is 0.4 ± 0.02 mM. Finally, flow cytometry analysis revealed that the threshold dose of zinc oxide nanoparticles was lethal to proliferating pluripotent mesenchymal stem cells but exhibited negligible cytotoxic effects to osteogenically differentiated mesenchymal stem cells. Conclusion: Results confirm the ZnO NP selective cytotoxic action on rapidly proliferating cells, whether benign or malignant. PMID:21698081

  15. Zinc oxide nanoparticles as selective killers of proliferating cells.

    PubMed

    Taccola, Liuba; Raffa, Vittoria; Riggio, Cristina; Vittorio, Orazio; Iorio, Maria Carla; Vanacore, Renato; Pietrabissa, Andrea; Cuschieri, Alfred

    2011-01-01

    It has recently been demonstrated that zinc oxide nanoparticles (ZnO NPs) induce death of cancerous cells whilst having no cytotoxic effect on normal cells. However, there are several issues which need to be resolved before translation of zinc oxide nanoparticles into medical use, including lack of suitable biocompatible dispersion protocols and a better understanding being needed of the mechanism of their selective cytotoxic action. Nanoparticle dose affecting cell viability was evaluated in a model of proliferating cells both experimentally and mathematically. The key issue of selective toxicity of ZnO NPs toward proliferating cells was addressed by experiments using a biological model of noncancerous cells, ie, mesenchymal stem cells before and after cell differentiation to the osteogenic lineage. In this paper, we report a biocompatible protocol for preparation of stable aqueous solutions of monodispersed zinc oxide nanoparticles. We found that the threshold of intracellular ZnO NP concentration required to induce cell death in proliferating cells is 0.4 ± 0.02 mM. Finally, flow cytometry analysis revealed that the threshold dose of zinc oxide nanoparticles was lethal to proliferating pluripotent mesenchymal stem cells but exhibited negligible cytotoxic effects to osteogenically differentiated mesenchymal stem cells. Results confirm the ZnO NP selective cytotoxic action on rapidly proliferating cells, whether benign or malignant.

  16. Chromosome Aberrations in Normal and Ataxia-Telangiectasia Cells Exposed to Heavy Ions

    NASA Technical Reports Server (NTRS)

    Kawata, T.; Ito, H.; Liu, C.; Shigematsu, N.; George, K.; Cucinotta, F. A.

    2007-01-01

    Although cells derived from Ataxia Telangiectasia (AT) patients are known to exhibit abnormal responses to ionizing radiations, its underlying mechanism still remains unclear. Previously, the authors reported that at the same gamma-irradiation dose AT cells show higher frequencies of misrepair and deletions compared to normal human fibroblast cells. In this study, we investigated the effects of heavy ions beams on chromosomal aberrations in normal and AT cells. Normal and AT fibroblast cells arrested at G0/G1 phase were irradiated with 2 Gy of X-rays, 490 MeV/u Silicon (LET 55 keV/m), 500 MeV/u Iron (LET 185 keV/m) and 200 MeV/u Iron (LET 440 keV/m) particles, and then cells were allowed to repair for 24 hours at 37 degrees before subculture. Calyculin-A induced PCC method was employed to collect G2/M chromosomes and whole DNA probes 1 and 3 were used to analyze chromosomal aberrations such as color-junctions, deletions, simple exchanges (incomplete and reciprocal exanges) and complex-type exchanges. The percentages of aberrant cells were higher when normal and AT cells were exposed to heavy ions compared to X-rays, and had a tendency to increase with increasing LET up to 185 keV/m and then decreased at 440 keV/m. When the frequency of color-junctions per cell was compared after X-ray exposure, AT cells had around three times higher frequency of color-junctions (mis-rejoining) than normal cells. However, at 185 keV/m there was no difference in the frequency of color-junctions between two cell lines. It was also found that the frequency of simple exchanges per cell was almost constant in AT cells regardless LET levels, but it was LET dependent for normal cells. Interestingly, the frequency of simple exchanges was higher for AT cells when it was compared at 185 keV/m but AT cells had more complex-type exchanges at the same LET levels. Heavy ions are more efficient in inducing chromosome aberrations in normal and AT cells compared to X-rays, and the aberration types

  17. Aberrant antibody affinity selection in SHIP-deficient B cells.

    PubMed

    Leung, Wai-Hang; Tarasenko, Tatiana; Biesova, Zuzana; Kole, Hemanta; Walsh, Elizabeth R; Bolland, Silvia

    2013-02-01

    The strength of the Ag receptor signal influences development and negative selection of B cells, and it might also affect B-cell survival and selection in the GC. Here, we have used mice with B-cell-specific deletion of the 5'-inositol phosphatase SHIP as a model to study affinity selection in cells that are hyperresponsive to Ag and cytokine receptor stimulation. In the absence of SHIP, B cells have lower thresholds for Ag- and interferon (IFN)-induced activation, resulting in augmented negative selection in the BM and enhanced B-cell maturation in the periphery. Despite a tendency to spontaneously downregulate surface IgM expression, SHIP deficiency does not alter anergy induction in response to soluble hen-egg lysozyme Ag in the MDA4 transgenic model. SHIP-deficient B cells spontaneously produce isotype-switched antibodies; however, they are poor responders in immunization and infection models. While SHIP-deficient B cells form GCs and undergo mutation, they are not properly selected for high-affinity antibodies. These results illustrate the importance of negative regulation of B-cell responses, as lower thresholds for B-cell activation promote survival of low affinity and deleterious receptors to the detriment of optimal Ab affinity maturation. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Peroxisome proliferator-activated receptor gamma overexpression suppresses proliferation of human colon cancer cells

    SciTech Connect

    Tsukahara, Tamotsu, E-mail: ttamotsu@shinshu-u.ac.jp; Haniu, Hisao

    2012-08-03

    Highlights: Black-Right-Pointing-Pointer We examined the correlation between PPAR{gamma} expression and cell proliferation. Black-Right-Pointing-Pointer PPAR{gamma} overexpression reduces cell viability. Black-Right-Pointing-Pointer We show the synergistic effect of cell growth inhibition by a PPAR{gamma} agonist. -- Abstract: Peroxisome proliferator-activated receptor gamma (PPAR{gamma}) plays an important role in the differentiation of intestinal cells and tissues. Our previous reports indicate that PPAR{gamma} is expressed at considerable levels in human colon cancer cells. This suggests that PPAR{gamma} expression may be an important factor for cell growth regulation in colon cancer. In this study, we investigated PPAR{gamma} expression in 4 human colon cancer cell lines, HT-29, LOVO,more » DLD-1, and Caco-2. Real-time polymerase chain reaction (PCR) and Western blot analysis revealed that the relative levels of PPAR{gamma} mRNA and protein in these cells were in the order HT-29 > LOVO > Caco-2 > DLD-1. We also found that PPAR{gamma} overexpression promoted cell growth inhibition in PPAR{gamma} lower-expressing cell lines (Caco-2 and DLD-1), but not in higher-expressing cells (HT-29 and LOVO). We observed a correlation between the level of PPAR{gamma} expression and the cells' sensitivity for proliferation.« less

  19. Food consumption increases cell proliferation in the python brain.

    PubMed

    Habroun, Stacy S; Schaffner, Andrew A; Taylor, Emily N; Strand, Christine R

    2018-04-06

    Pythons are model organisms for investigating physiological responses to food intake. While systemic growth in response to food consumption is well documented, what occurs in the brain is currently unexplored. In this study, male ball pythons ( Python regius ) were used to test the hypothesis that food consumption stimulates cell proliferation in the brain. We used 5-bromo-12'-deoxyuridine (BrdU) as a cell-birth marker to quantify and compare cell proliferation in the brain of fasted snakes and those at 2 and 6 days after a meal. Throughout the telencephalon, cell proliferation was significantly increased in the 6 day group, with no difference between the 2 day group and controls. Systemic postprandial plasticity occurs quickly after a meal is ingested, during the period of active digestion; however, the brain displays a surge of cell proliferation after most digestion and absorption is complete. © 2018. Published by The Company of Biologists Ltd.

  20. Induction of Malignant Plasma Cell Proliferation by Eosinophils

    PubMed Central

    Wong, Tina W.; Kita, Hirohito; Hanson, Curtis A.; Walters, Denise K.; Arendt, Bonnie K.; Jelinek, Diane F.

    2013-01-01

    The biology of the malignant plasma cells (PCs) in multiple myeloma (MM) is highly influenced by the bone marrow (BM) microenvironment in which they reside. More specifically, BM stromal cells (SCs) are known to interact with MM cells to promote MM cell survival and proliferation. By contrast, it is unclear if innate immune cells within this same space also actively participate in the pathology of MM. Our study shows for the first time that eosinophils (Eos) can contribute to the biology of MM by enhancing the proliferation of some malignant PCs. We first demonstrate that PCs and Eos can be found in close proximity in the BM. In culture, Eos were found to augment MM cell proliferation that is predominantly mediated through a soluble factor(s). Fractionation of cell-free supernatants and neutralization studies demonstrated that this activity is independent of Eos-derived microparticles and a proliferation-inducing ligand (APRIL), respectively. Using a multicellular in vitro system designed to resemble the native MM niche, SCs and Eos were shown to have non-redundant roles in their support of MM cell growth. Whereas SCs induce MM cell proliferation predominantly through the secretion of IL-6, Eos stimulate growth of these malignant cells via an IL-6-independent mechanism. Taken together, our study demonstrates for the first time a role for Eos in the pathology of MM and suggests that therapeutic strategies targeting these cells may be beneficial. PMID:23894671

  1. 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.

  2. Cell proliferation of Paramecium tetraurelia on a slow rotating clinostat

    NASA Astrophysics Data System (ADS)

    Sawai, Satoe; Mogami, Yoshihiro; Baba, Shoji A.

    Paramecium is known to proliferate faster under microgravity conditions, and slower under hypergravity. Experiments using axenic culture medium have demonstrated that hypergravity affected directly on the proliferation of Paramecium itself. In order to assess the mechanisms underlying the physiological effects of gravity on cell proliferation, Paramecium tetraurelia was grown under clinorotation (2.5 rpm) and the time course of the proliferation was investigated in detail on the basis of the logistic analysis. On the basis of the mechanical properties of Paramecium, this slow rate of the rotation appears to be enough to simulate microgravity in terms of the randomization of the cell orientation with respect to gravity. P. tetraurelia was cultivated in a closed chamber in which cells were confined without air bubbles, reducing the shear forces and turbulences under clinorotation. The chamber is made of quartz and silicone rubber film; the former is for the optically-flat walls for the measurement of cell density by means of a non-invasive laser optical-slice method, and the latter for gas exchange. Because of the small dimension for culture space, Paramecium does not accumulate at the top of the chamber in spite of its known negative gravitactic behavior. We measured the cell density at regular time intervals without breaking the configuration of the chamber, and analyzed the proliferation parameters by fitting the data to a logistic equation. As a result, P. tetraurelia showed reduced proliferation under slow clinorotation. The saturation of the cell density as well as the maximum proliferation rate decreased, although we found no significant changes on the half maximal time for proliferation. We also found that the mean swimming velocity decreased under slow clinorotation. These results were not consistent with those under microgravity and fast rotating clinostat. This may suggest that randomization of the cell orientation performed by slow rotating clinostat has

  3. High-LET Radiation Induced Chromosome Aberrations in Normal and Ataxia Telangiectasia Fibroblast Cells

    NASA Astrophysics Data System (ADS)

    Kawata, Tetsuya; George, Ms Kerry; Cucinotta, Francis A.; Shigematsu, Naoyuki; Ito, Hisao; Furusawa, Yoshiya; Uno, Takashi

    We investigated the effects of heavy ions beams on chromosomal aberrations in normal and AT cells. Normal and AT fibroblast cells arrested at G0/G1 phase were irradiated with 2 Gy of X-rays, 490 MeV/u Silicon (LET 55 keV/micron), 500 MeV/u Iron (LET 185 keV/micron) and 200 MeV/u Iron (LET 440 keV/micron) particles, and then cells were allowed to repair for 24 hours at 37 degrees before subculture. Calyculin-A induced PCC method was employed to collect G2/M chromosomes and whole DNA probes 1 and 3 were used to analyze chromosomal aberrations such as color-junctions, deletions, simple exchanges (incomplete and reciprocal exchanges) and complex-type exchanges. The percentages of aberrant cells were higher when normal and AT cells were exposed to heavy ions compared to X-rays, and had a tendency to increase with increasing LET up to 185 keV/micron and then decreased at 440 keV/micron. When the frequency of color-junctions per cell was compared after X-ray exposure, AT cells had around three times higher frequency of color-junctions (mis-rejoining) than normal cells. However, at 185 keV/micron there was no difference in the frequency of color-junctions between two cell lines. It was also found that the frequency of simple exchanges per cell was almost constant in AT cells regardless LET levels, but it was LET dependent for normal cells. Interestingly, the frequency of simple exchanges was higher for normal fibroblast cells when it was compared at 185 keV/micron, but AT cells had more complex-type exchanges at the same LET levels. Heavy ions are more efficient in inducing chromosome aberrations in normal and AT cells compared to X-rays, and the aberration types between normal and AT fibroblast appeared different probably due to difference in the ATM gene function.

  4. Effects of alpha-particles on survival and chromosomal aberrations in human mammary epithelial cells

    NASA Technical Reports Server (NTRS)

    Durante, M.; Grossi, G. F.; Gialanella, G.; Pugliese, M.; Nappo, M.; Yang, T. C.

    1995-01-01

    We have studied the radiation responses of a human mammary epithelial cell line, H184B5 F5-1 M/10. This cell line was derived from primary mammary cells after treatment with chemicals and heavy ions. The F5-1 M/10 cells are immortal, density-inhibited in growth, and non-tumorigenic in athymic nude mice and represent an in vitro model of the human epithelium for radiation studies. Because epithelial cells are the target of alpha-particles emitted from radon daughters, we concentrated our studies on the efficiency of alpha-particles. Confluent cultures of M/10 cells were exposed to accelerated alpha-particles [beam energy incident at the cell monolayer = 3.85 MeV, incident linear energy transfer (LET) in cell = 109 keV/microns] and, for comparison, to 80 kVp x-rays. The following endpoints were studied: (1) survival, (2) chromosome aberrations at the first postirradiation mitosis, and (3) chromosome alterations at later passages following irradiation. The survival curve was exponential for alpha-particles (D0 = 0.73 +/- 0.04 Gy), while a shoulder was observed for x-rays (alpha/beta = 2.9 Gy; D0 = 2.5 Gy, extrapolation number 1.6). The relative biological effectiveness (RBE) of high-LET alpha-particles for human epithelial cell killing was 3.3 at 37% survival. Dose-response curves for the induction of chromosome aberrations were linear for alpha-particles and linearquadratic for x-rays. The RBE for the induction of chromosome aberrations varied with the type of aberration scored and was high (about 5) for chromosome breaks and low (about 2) for chromosome exchanges.(ABSTRACT TRUNCATED AT 250 WORDS).

  5. Effects of alpha-particles on survival and chromosomal aberrations in human mammary epithelial cells.

    PubMed

    Durante, M; Grossi, G F; Gialanella, G; Pugliese, M; Nappo, M; Yang, T C

    1995-08-01

    We have studied the radiation responses of a human mammary epithelial cell line, H184B5 F5-1 M/10. This cell line was derived from primary mammary cells after treatment with chemicals and heavy ions. The F5-1 M/10 cells are immortal, density-inhibited in growth, and non-tumorigenic in athymic nude mice and represent an in vitro model of the human epithelium for radiation studies. Because epithelial cells are the target of alpha-particles emitted from radon daughters, we concentrated our studies on the efficiency of alpha-particles. Confluent cultures of M/10 cells were exposed to accelerated alpha-particles [beam energy incident at the cell monolayer = 3.85 MeV, incident linear energy transfer (LET) in cell = 109 keV/microns] and, for comparison, to 80 kVp x-rays. The following endpoints were studied: (1) survival, (2) chromosome aberrations at the first postirradiation mitosis, and (3) chromosome alterations at later passages following irradiation. The survival curve was exponential for alpha-particles (D0 = 0.73 +/- 0.04 Gy), while a shoulder was observed for x-rays (alpha/beta = 2.9 Gy; D0 = 2.5 Gy, extrapolation number 1.6). The relative biological effectiveness (RBE) of high-LET alpha-particles for human epithelial cell killing was 3.3 at 37% survival. Dose-response curves for the induction of chromosome aberrations were linear for alpha-particles and linearquadratic for x-rays. The RBE for the induction of chromosome aberrations varied with the type of aberration scored and was high (about 5) for chromosome breaks and low (about 2) for chromosome exchanges.(ABSTRACT TRUNCATED AT 250 WORDS)

  6. Cell proliferation of Paramecium tetraurelia under simulated microgravity

    NASA Astrophysics Data System (ADS)

    Sawai, S.; Mogami, Y.; Baba, S. A.

    Paramecium is known to proliferate faster under microgravity in space and slower under hypergravity Experiments using axenic culture medium have demonstrated that the hypergravity affected directly on the proliferation of Paramecium itself Kato et al 2003 In order to assess the mechanisms underlying the physiological effects of gravity on cell proliferation Paramecium tetraurelia was grown under simulated microgravity performed by clinorotation and the time course of the proliferation was investigated in detail on the basis of the logistic analysis P tetraurelia was cultivated in a closed chamber in which cells were confined without air babbles reducing the shear stresses and turbulence under the rotation The chamber is made of quartz and silicone rubber film the former is for the optically-flat walls for the measurement of cell density by means of a non-invasive laser optical-slice method and the latter for gas exchange Because the closed chamber has an inner dimension of 3 times 3 times 60 mm Paramecium does not accumulate at the top of the chamber despite its negative gravitactic behavior We measured the cell density at regular time intervals without breaking the configuration of the chamber and analyzed the proliferation parameters by fitting the data to a logistic equation Clinorotation had the effects of reducing the proliferation of P tetraurelia It reduced both the saturation cell density and the maximum proliferation rate although it had little effect on the

  7. Cell lines derived from feline fibrosarcoma display unstable chromosomal aneuploidy and additionally centrosome number aberrations.

    PubMed

    von Erichsen, J; Hecht, W; Löhberg-Gruene, C; Reinacher, M

    2012-07-01

    The purpose of the study was to evaluate clonality and presence of numerical chromosomal and centrosomal aberrations in 5 established feline fibrosarcoma cell lines and in a fetal dermal fibroblast cell line as a control. The clonality of all cell lines was examined using limited-dilution cloning. The number of chromosomes was counted in metaphase spreads. The immunocytochemical analysis of centrosome numbers was performed by indirect immunofluorescence using a monoclonal antibody that targets γ-tubulin, a well-characterized component of centrosomes. Monoclonal cell populations could be established from all cell lines. In all feline fibrosarcoma cell lines, the number of chromosomes deviated abnormally from the normal feline chromosome number of 2n = 38, ranging from 19 to 155 chromosomes per cell. Centrosome hyperamplification was observed in all 5 feline fibrosarcoma cell lines with a proportion of cells (5.7 to 15.2%) having more than 2 centrosomes. In the control cell line, only 0.6% of the cells had more than 2 centrosomes. In conclusion, the examinations revealed that centrosome hyperamplification occurs in feline fibrosarcoma cell lines. The feline fibrosarcoma cell lines possessed 10 to 25 times as many cells with centrosome hyperamplification as the control cell line. These observations suggest an association of numerical centrosome aberrations with karyotype instability by increasing the frequency of chromosome missegregation. The results of this study may be helpful for further characterization of feline fibrosarcomas and may contribute to the knowledge of cytogenetic factors that may be important for the pathogenesis of feline fibrosarcomas.

  8. Aberrant expression of the PHF14 gene in biliary tract cancer cells

    PubMed Central

    AKAZAWA, TAKAKO; YASUI, KOHICHIROH; GEN, YASUYUKI; YAMADA, NOBUHISA; TOMIE, AKIRA; DOHI, OSAMU; MITSUYOSHI, HIRONORI; YAGI, NOBUAKI; ITOH, YOSHITO; NAITO, YUJI; YOSHIKAWA, TOSHIKAZU

    2013-01-01

    DNA copy number aberrations in human biliary tract cancer (BTC) cell lines were investigated using a high-density oligonucleotide microarray. A novel homozygous deletion was detected at chromosomal region 7p21.3 in the OZ cell line. Further validation experiments using genomic PCR revealed a homozygous deletion of a single gene, plant homeodomain (PHD) finger protein 14 (PHF14). No PHF14 mRNA or protein expression was detected, thus demonstrating the absence of PHF14 expression in the OZ cell line. Although the PHD finger protein is considered to be involved in chromatin-mediated transcriptional regulation, little is known about the function of PHF14 in cancer. The present study observed that the knock down of PHF14 using small interfering RNA (siRNA) enhanced the growth of the BTC cells. These observations suggest that aberrant PHF14 expression may have a role in the tumorigenesis of BTC. PMID:23833654

  9. Effects of nicotinamide N-methyltransferase on PANC-1 cells proliferation, metastatic potential and survival under metabolic stress.

    PubMed

    Yu, Tao; Wang, Yong-Tao; Chen, Pan; Li, Yu-Hua; Chen, Yi-Xin; Zeng, Hang; Yu, Ai-Ming; Huang, Min; Bi, Hui-Chang

    2015-01-01

    Aberrant expression of Nicotinamide N-methyltransferase (NNMT) has been reported in pancreatic cancer. However, the role of NNMT in pancreatic cancer development remains elusive. Therefore, the present study was to investigate the impact of NNMT on pancreatic cancer cell proliferation, metastatic potential and survival under metabolic stress. Pancreatic cancer cell line PANC-1 was transfected with NNMT expression plasmid or small interfering RNA of NNMT to overexpress or knockdown intracellular NNMT expression, respectively. Rate of cell proliferation was monitored. Transwell migration and matrigel invasion assays were conducted to assess cell migration and invasion capacity. Resistance to glucose deprivation, sensitivity to glycolytic inhibition, mitochondrial inhibtion and resistance to rapamycin were examined to evaluate cell survival under metabolic stress. NNMT silencing markedly reduced cell proliferation, whereas NNMT overexpression promoted cell growth moderately. Knocking down NNMT also significantly suppressed the migration and invasion capacities of PANC-1 cells. Conversely, NNMT upregulation enhanced cell migration and invasion capacities. In addition, NNMT knockdown cells were much less resistant to glucose deprivation and rapamycin as well as glycolytic inhibitor 2-deoxyglucose whereas NNMT-expressing cells showed opposite effects although the effects were not so striking. These data sugguest that NNMT plays an important role in PANC-1 cell proliferation, metastatic potential and survival under metabolic stress. © 2015 S. Karger AG, Basel.

  10. Aberrant Signaling Pathways in T-Cell Acute Lymphoblastic Leukemia

    PubMed Central

    Bongiovanni, Deborah; Saccomani, Valentina

    2017-01-01

    T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive disease caused by the malignant transformation of immature progenitors primed towards T-cell development. Clinically, T-ALL patients present with diffuse infiltration of the bone marrow by immature T-cell blasts high blood cell counts, mediastinal involvement, and diffusion to the central nervous system. In the past decade, the genomic landscape of T-ALL has been the target of intense research. The identification of specific genomic alterations has contributed to identify strong oncogenic drivers and signaling pathways regulating leukemia growth. Notwithstanding, T-ALL patients are still treated with high-dose multiagent chemotherapy, potentially exposing these patients to considerable acute and long-term side effects. This review summarizes recent advances in our understanding of the signaling pathways relevant for the pathogenesis of T-ALL and the opportunities offered for targeted therapy. PMID:28872614

  11. Influence of homologous recombinational repair on cell survival and chromosomal aberration induction during the cell cycle in γ-irradiated CHO cells

    PubMed Central

    Wilson, Paul F.; Hinz, John M.; Urbin, Salustra S.; Nham, Peter B.; Thompson, Larry H.

    2010-01-01

    The repair of DNA double-strand breaks (DSB) by homologous recombinational repair (HRR) underlies the high radioresistance and low mutability observed in S-phase mammalian cells. To evaluate the contributions of HRR and nonhomologous end-joining (NHEJ) to overall DSB repair capacity throughout the cell cycle after γ-irradiation, we compared HRR-deficient RAD51D-knockout 51D1 to CgRAD51D-complemented 51D1 (51D1.3) CHO cells for survival and chromosomal aberrations (CAs). Asynchronous cultures were irradiated with 150 or 300 cGy and separated by cell size using centrifugal elutriation. Cell survival of each synchronous fraction (~20 fractions total from early G1 to late G2/M) was measured by colony formation. 51D1.3 cells were most resistant in S, while 51D1 cells were most resistant in early G1 (with survival and chromosome-type CA levels similar to 51D1.3) and became progressively more sensitive throughout S and G2. Both cell lines experienced significantly reduced survival from late S into G2. Metaphases were collected from every third elutriation fraction at the first post-irradiation mitosis and scored for CAs. 51D1 cells irradiated in S and G2 had ~2-fold higher chromatid-type CAs and a remarkable ~25-fold higher level of complex chromatid-type exchanges compared to 51D1.3 cells. Complex exchanges in 51D1.3 cells were only observed in G2. These results show an essential role for HRR in preventing gross chromosomal rearrangements in proliferating cells and, with our previous report of reduced survival of G2-phase NHEJ-deficient prkdc CHO cells [Hinz et al. DNA Repair 4, 782–792, 2005], imply reduced activity/efficiency of both HRR and NHEJ as cells transition from S to G2. PMID:20434408

  12. Chromosomal Aberrations in Normal and AT Cells Exposed to High Dose of Low Dose Rate Irradiation

    NASA Technical Reports Server (NTRS)

    Kawata, T.; Shigematsu, N.; Kawaguchi, O.; Liu, C.; Furusawa, Y.; Hirayama, R.; George, K.; Cucinotta, F.

    2011-01-01

    Ataxia telangiectasia (A-T) is a human autosomally recessive syndrome characterized by cerebellar ataxia, telangiectases, immune dysfunction, and genomic instability, and high rate of cancer incidence. A-T cell lines are abnormally sensitive to agents that induce DNA double strand breaks, including ionizing radiation. The diverse clinical features in individuals affected by A-T and the complex cellular phenotypes are all linked to the functional inactivation of a single gene (AT mutated). It is well known that cells deficient in ATM show increased yields of both simple and complex chromosomal aberrations after high-dose-rate irradiation, but, less is known on how cells respond to low-dose-rate irradiation. It has been shown that AT cells contain a large number of unrejoined breaks after both low-dose-rate irradiation and high-dose-rate irradiation, however sensitivity for chromosomal aberrations at low-dose-rate are less often studied. To study how AT cells respond to low-dose-rate irradiation, we exposed confluent normal and AT fibroblast cells to up to 3 Gy of gamma-irradiation at a dose rate of 0.5 Gy/day and analyzed chromosomal aberrations in G0 using fusion PCC (Premature Chromosomal Condensation) technique. Giemsa staining showed that 1 Gy induces around 0.36 unrejoined fragments per cell in normal cells and around 1.35 fragments in AT cells, whereas 3Gy induces around 0.65 fragments in normal cells and around 3.3 fragments in AT cells. This result indicates that AT cells can rejoin breaks less effectively in G0 phase of the cell cycle? compared to normal cells. We also analyzed chromosomal exchanges in normal and AT cells after exposure to 3 Gy of low-dose-rate rays using a combination of G0 PCC and FISH techniques. Misrejoining was detected in the AT cells only? When cells irradiated with 3 Gy were subcultured and G2 chromosomal aberrations were analyzed using calyculin-A induced PCC technique, the yield of unrejoined breaks decreased in both normal and AT

  13. Inhibition of brain tumor cell proliferation by alternating electric fields

    SciTech Connect

    Jeong, Hyesun; Oh, Seung-ick; Hong, Sunghoi, E-mail: shong21@korea.ac.kr, E-mail: radioyoon@korea.ac.kr

    2014-11-17

    This study was designed to investigate the mechanism by which electric fields affect cell function, and to determine the optimal conditions for electric field inhibition of cancer cell proliferation. Low-intensity (<2 V/cm) and intermediate-frequency (100–300 kHz) alternating electric fields were applied to glioblastoma cell lines. These electric fields inhibited cell proliferation by inducing cell cycle arrest and abnormal mitosis due to the malformation of microtubules. These effects were significantly dependent on the intensity and frequency of applied electric fields.

  14. TET1 Depletion Induces Aberrant CpG Methylation in Colorectal Cancer Cells

    PubMed Central

    Yamamoto, Eiichiro; Harada, Taku; Aoki, Hironori; Maruyama, Reo; Toyota, Mutsumi; Sasaki, Yasushi; Sugai, Tamotsu; Tokino, Takashi; Nakase, Hiroshi

    2016-01-01

    Aberrant DNA methylation is commonly observed in colorectal cancer (CRC), but the underlying mechanism is not fully understood. 5-hydroxymethylcytosine levels and TET1 expression are both reduced in CRC, while epigenetic silencing of TET1 is reportedly associated with the CpG island methylator phenotype. In the present study, we aimed to clarify the relationship between loss of TET1 and aberrant DNA methylation in CRC. Stable TET1 knockdown clones were established using Colo320DM cells, which express high levels of TET1, and HCT116 cells, which express TET1 at a level similar to that in normal colonic tissue. Infinium HumanMethylation450 BeadChip assays revealed increased levels of 5-methylcytosine at more than 10,000 CpG sites in TET1-depleted Colo320DM cells. Changes in DNA methylation were observed at various positions within the genome, including promoters, gene bodies and intergenic regions, and the altered methylation affected expression of a subset of genes. By contrast, TET1 knockdown did not significantly affect DNA methylation in HCT116 cells. However, TET1 depletion was associated with attenuated effects of 5-aza-2’-deoxycytidine on gene expression profiles in both cell lines. These results suggest that loss of TET1 may induce aberrant DNA methylation and may attenuate the effect of 5-aza-2’-deoxycytidine in CRC cells. PMID:27977763

  15. BET bromodomain proteins are required for glioblastoma cell proliferation.

    PubMed

    Pastori, Chiara; Daniel, Mark; Penas, Clara; Volmar, Claude-Henry; Johnstone, Andrea L; Brothers, Shaun P; Graham, Regina M; Allen, Bryce; Sarkaria, Jann N; Komotar, Ricardo J; Wahlestedt, Claes; Ayad, Nagi G

    2014-04-01

    Epigenetic proteins have recently emerged as novel anticancer targets. Among these, bromodomain and extra terminal domain (BET) proteins recognize lysine-acetylated histones, thereby regulating gene expression. Newly described small molecules that inhibit BET proteins BRD2, BRD3, and BRD4 reduce proliferation of NUT (nuclear protein in testis)-midline carcinoma, multiple myeloma, and leukemia cells in vitro and in vivo. These findings prompted us to determine whether BET proteins may be therapeutic targets in the most common primary adult brain tumor, glioblastoma (GBM). We performed NanoString analysis of GBM tumor samples and controls to identify novel therapeutic targets. Several cell proliferation assays of GBM cell lines and stem cells were used to analyze the efficacy of the drug I-BET151 relative to temozolomide (TMZ) or cell cycle inhibitors. Lastly, we performed xenograft experiments to determine the efficacy of I-BET151 in vivo. We demonstrate that BRD2 and BRD4 RNA are significantly overexpressed in GBM, suggesting that BET protein inhibition may be an effective means of reducing GBM cell proliferation. Disruption of BRD4 expression in glioblastoma cells reduced cell cycle progression. Similarly, treatment with the BET protein inhibitor I-BET151 reduced GBM cell proliferation in vitro and in vivo. I-BET151 treatment enriched cells at the G1/S cell cycle transition. Importantly, I-BET151 is as potent at inhibiting GBM cell proliferation as TMZ, the current chemotherapy treatment administered to GBM patients. Since I-BET151 inhibits GBM cell proliferation by arresting cell cycle progression, we propose that BET protein inhibition may be a viable therapeutic option for GBM patients suffering from TMZ resistant tumors.

  16. BET bromodomain proteins are required for glioblastoma cell proliferation

    PubMed Central

    Pastori, Chiara; Daniel, Mark; Penas, Clara; Volmar, Claude-Henry; Johnstone, Andrea L; Brothers, Shaun P; Graham, Regina M; Allen, Bryce; Sarkaria, Jann N; Komotar, Ricardo J; Wahlestedt, Claes; Ayad, Nagi G

    2014-01-01

    Epigenetic proteins have recently emerged as novel anticancer targets. Among these, bromodomain and extra terminal domain (BET) proteins recognize lysine-acetylated histones, thereby regulating gene expression. Newly described small molecules that inhibit BET proteins BRD2, BRD3, and BRD4 reduce proliferation of NUT (nuclear protein in testis)-midline carcinoma, multiple myeloma, and leukemia cells in vitro and in vivo. These findings prompted us to determine whether BET proteins may be therapeutic targets in the most common primary adult brain tumor, glioblastoma (GBM). We performed NanoString analysis of GBM tumor samples and controls to identify novel therapeutic targets. Several cell proliferation assays of GBM cell lines and stem cells were used to analyze the efficacy of the drug I-BET151 relative to temozolomide (TMZ) or cell cycle inhibitors. Lastly, we performed xenograft experiments to determine the efficacy of I-BET151 in vivo. We demonstrate that BRD2 and BRD4 RNA are significantly overexpressed in GBM, suggesting that BET protein inhibition may be an effective means of reducing GBM cell proliferation. Disruption of BRD4 expression in glioblastoma cells reduced cell cycle progression. Similarly, treatment with the BET protein inhibitor I-BET151 reduced GBM cell proliferation in vitro and in vivo. I-BET151 treatment enriched cells at the G1/S cell cycle transition. Importantly, I-BET151 is as potent at inhibiting GBM cell proliferation as TMZ, the current chemotherapy treatment administered to GBM patients. Since I-BET151 inhibits GBM cell proliferation by arresting cell cycle progression, we propose that BET protein inhibition may be a viable therapeutic option for GBM patients suffering from TMZ resistant tumors. PMID:24496381

  17. Scaffold architecture and fibrin gels promote meniscal cell proliferation

    SciTech Connect

    Pawelec, K. M., E-mail: pawelec.km@gmail.com, E-mail: jw626@cam.ac.uk; Best, S. M.; Cameron, R. E.

    2015-01-01

    Stability of the knee relies on the meniscus, a complex connective tissue with poor healing ability. Current meniscal tissue engineering is inadequate, as the signals for increasing meniscal cell proliferation have not been established. In this study, collagen scaffold structure, isotropic or aligned, and fibrin gel addition were tested. Metabolic activity was promoted by fibrin addition. Cellular proliferation, however, was significantly increased by both aligned architectures and fibrin addition. None of the constructs impaired collagen type I production or triggered adverse inflammatory responses. It was demonstrated that both fibrin gel addition and optimized scaffold architecture effectively promote meniscal cell proliferation.

  18. EDA-containing fibronectin increases proliferation of embryonic stem cells.

    PubMed

    Losino, Noelia; Waisman, Ariel; Solari, Claudia; Luzzani, Carlos; Espinosa, Darío Fernández; Sassone, Alina; Muro, Andrés F; Miriuka, Santiago; Sevlever, Gustavo; Barañao, Lino; Guberman, Alejandra

    2013-01-01

    Embryonic stem cells (ESC) need a set of specific factors to be propagated. They can also grow in conditioned medium (CM) derived from a bovine granulosa cell line BGC (BGC-CM), a medium that not only preserves their main features but also increases ESC´s proliferation rate. The mitogenic properties of this medium were previously reported, ascribing this effect to an alternative spliced generated fibronectin isoform that contains the extra domain A (FN EDA(+)). Here, we investigated if the FN EDA(+) isoform increased proliferation of mouse and human ES cells. We analyzed cell proliferation using conditioned media produced by different mouse embryonic fibroblast (MEF) lines genetically engineered to express FN constitutively including or excluding the EDA domain (FN EDA(-)), and in media supplemented with recombinant peptides containing or not the EDA. We found that the presence of EDA in the medium increased mouse and human ESC's proliferation rate. Here we showed for the first time that this FN isoform enhances ESC's proliferation. These findings suggest a possible conserved behavior for regulation of ES cells proliferation by this FN isoform and could contribute to improve their culturing conditions both for research and cell therapy.

  19. EDA-Containing Fibronectin Increases Proliferation of Embryonic Stem Cells

    PubMed Central

    Losino, Noelia; Waisman, Ariel; Solari, Claudia; Luzzani, Carlos; Espinosa, Darío Fernández; Sassone, Alina; Muro, Andrés F.; Miriuka, Santiago; Sevlever, Gustavo; Barañao, Lino; Guberman, Alejandra

    2013-01-01

    Embryonic stem cells (ESC) need a set of specific factors to be propagated. They can also grow in conditioned medium (CM) derived from a bovine granulosa cell line BGC (BGC-CM), a medium that not only preserves their main features but also increases ESC´s proliferation rate. The mitogenic properties of this medium were previously reported, ascribing this effect to an alternative spliced generated fibronectin isoform that contains the extra domain A (FN EDA+). Here, we investigated if the FN EDA+ isoform increased proliferation of mouse and human ES cells. We analyzed cell proliferation using conditioned media produced by different mouse embryonic fibroblast (MEF) lines genetically engineered to express FN constitutively including or excluding the EDA domain (FN EDA-), and in media supplemented with recombinant peptides containing or not the EDA. We found that the presence of EDA in the medium increased mouse and human ESC’s proliferation rate. Here we showed for the first time that this FN isoform enhances ESC’s proliferation. These findings suggest a possible conserved behavior for regulation of ES cells proliferation by this FN isoform and could contribute to improve their culturing conditions both for research and cell therapy. PMID:24244705

  20. Cellular distribution of cell cycle-related molecules in the renal tubules of rats treated with renal carcinogens for 28 days: relationship between cell cycle aberration and carcinogenesis.

    PubMed

    Taniai, Eriko; Hayashi, Hitomi; Yafune, Atsunori; Watanabe, Maiko; Akane, Hirotoshi; Suzuki, Kazuhiko; Mitsumori, Kunitoshi; Shibutani, Makoto

    2012-09-01

    Some renal carcinogens can induce karyomegaly, which reflects aberrant cell division in the renal tubules, from the early stages of exposure. To clarify the cell cycle-related changes during the early stages of renal carcinogenesis, we performed immunohistochemical analysis of tubular cells in male F344 rats treated with carcinogenic doses of representative renal carcinogens for 28 days. For this purpose, the karyomegaly-inducing carcinogens ochratoxin A (OTA), ferric nitrilotriacetic acid, and monuron, and the non-karyomegaly-inducing carcinogens tris(2-chloroethyl) phosphate and potassium bromate were examined. For comparison, a karyomegaly-inducing non-carcinogen, p-nitrobenzoic acid, and a non-carcinogenic non-karyomegaly-inducing renal toxicant, acetaminophen, were also examined. The outer stripe of the outer medulla (OSOM) and the cortex + OSOM were subjected to morphometric analysis of immunoreactive proximal tubular cells. Renal carcinogens, irrespective of their karyomegaly-inducing potential, increased proximal tubular cell proliferation accompanied by an increase in topoisomerase IIα-immunoreactive cells, suggesting a reflection of cell proliferation. Karyomegaly-inducing carcinogens increased nuclear Cdc2-, γH2AX-, and phosphorylated Chk2-immunoreactive cells in both areas, the former two acting in response to DNA damage and the latter one suggestive of sustained G₂. OTA, an OSOM-targeting carcinogen, could easily be distinguished from untreated controls and non-carcinogens by evaluation of molecules responding to DNA damage and G₂/M transition in the OSOM. Thus, all renal carcinogens examined facilitated proximal tubular proliferation by repeated short-term treatment. Among these, karyomegaly-inducing carcinogens may cause DNA damage and G₂ arrest in the target tubular cells.

  1. Aluminum induces chromosome aberrations, micronuclei, and cell cycle dysfunction in root cells of Vicia faba.

    PubMed

    Yi, Min; Yi, Huilan; Li, Honghai; Wu, Lihua

    2010-04-01

    Aluminum (Al) exists naturally in air, water, and soil, and also in our diet. Al can be absorbed into the human body and accumulates in different tissues, which has been linked to the occurrence of Alzheimer's disease and various neurological disorders. By using Vicia cytogenetic tests, which are commonly used to monitor the genotoxicity of environmental pollutants, cytogenetic effects of aluminum (AlCl(3)) were investigated in this study. Present results showed that Al caused significant increases in the frequencies of micronuclei (MN) and anaphase chromosome aberrations in Vicia faba root tips exposed to Al over a concentration-tested range of 0.01-10 mM for 12 h. The frequency of micronucleated cells was higher in Al-treated groups at pH 4.5 than that at pH 5.8. Similarly, AlCl(3) treatment caused a decrease in the number of mitotic cells in a dose- and pH-dependent manner. The number of cells in each mitotic phase changed in Al-treated samples. Mitotic indices (MI) decreased with the increases of pycnotic cells. Our results demonstrate that aluminum chloride is a clear clastogenic/genotoxic and cytotoxic agent in Vicia root cells. The V. faba cytogenetic test could be used for the genotoxicity monitoring of aluminum water contamination.

  2. Clinical significance of SLP-2 in hepatocellular carcinoma tissues and its regulation in cancer cell proliferation, migration, and EMT

    PubMed Central

    Lin, Xiaoqi; Lin, Qingjun; Han, Ming; Guo, Guohu

    2017-01-01

    Stomatin-like protein 2 (SLP-2) gene was significantly upregulated in a variety of tumor tissues and found to be involved in proliferation and metastasis. However, its functional role in hepatocellular carcinoma (HCC) remains unknown. Our study was to investigate the function of SLP-2 in cell proliferation, migration, invasion, cell apoptosis, and the process of epithelial–mesenchymal transition (EMT) in HCC. SLP-2 mRNA and protein expression in HCC were assessed by qRT-PCR and immunohistochemical staining. In vitro, we determined cell proliferation, migration, invasion, and cell apoptosis by CCK-8, transwell, and flow cytometry assays, respectively. SLP-2 was found to be upregulated at both mRNA and protein levels in HCC tissues, and its aberrant overexpression was linked with poor prognosis in patients with HCC. SLP-2 downregulation by siRNAs significantly suppressed cell proliferation, migration, invasion, anti-apoptosis abilities, and inhibited EMT process in vitro. In conclusion, the present study demonstrated the overexpression of SLP-2 in HCC tissues for the first time. As an effective regulator involved in cell proliferation, migration, invasion, cell apoptosis, and EMT, SLP-2 could be a novel therapeutic target for patients with HCC who express high levels of SLP-2. PMID:29033585

  3. Clinical significance of SLP-2 in hepatocellular carcinoma tissues and its regulation in cancer cell proliferation, migration, and EMT.

    PubMed

    Huang, Yijie; Chen, Yexi; Lin, Xiaoqi; Lin, Qingjun; Han, Ming; Guo, Guohu

    2017-01-01

    Stomatin-like protein 2 ( SLP-2 ) gene was significantly upregulated in a variety of tumor tissues and found to be involved in proliferation and metastasis. However, its functional role in hepatocellular carcinoma (HCC) remains unknown. Our study was to investigate the function of SLP-2 in cell proliferation, migration, invasion, cell apoptosis, and the process of epithelial-mesenchymal transition (EMT) in HCC. SLP-2 mRNA and protein expression in HCC were assessed by qRT-PCR and immunohistochemical staining. In vitro, we determined cell proliferation, migration, invasion, and cell apoptosis by CCK-8, transwell, and flow cytometry assays, respectively. SLP-2 was found to be upregulated at both mRNA and protein levels in HCC tissues, and its aberrant overexpression was linked with poor prognosis in patients with HCC. SLP-2 downregulation by siRNAs significantly suppressed cell proliferation, migration, invasion, anti-apoptosis abilities, and inhibited EMT process in vitro. In conclusion, the present study demonstrated the overexpression of SLP-2 in HCC tissues for the first time. As an effective regulator involved in cell proliferation, migration, invasion, cell apoptosis, and EMT, SLP-2 could be a novel therapeutic target for patients with HCC who express high levels of SLP-2.

  4. Nesfatin-1 inhibits ovarian epithelial carcinoma cell proliferation in vitro

    SciTech Connect

    Xu, Yang; Pang, Xiaoyan; Dong, Mei

    Highlights: •Nesfatin-1 inhibits the proliferation and growth of HO-8910 cells by G1 phase arrest. •Nesfatin-1 enhances HO-8910 cell apoptosis. •Nesfatin-1 inhibits HO-8910 cell proliferation via mTOR and RhoA/ROCK signaling pathway. •The first report of nesfatin-1-mediated proliferation in ovarian epithelial carcinoma. -- Abstract: Nesfatin-1, an 82-amino-acid peptide derived from a 396-amino-acid precursor protein nucleobindin 2 (NUCB2), was originally identified in hypothalamic nuclei involved in the regulation of food intake. It was recently reported that nesfatin-1 is a novel depot specific adipokine preferentially produced by subcutaneous tissue, with obesity- and food deprivation-regulated expression. Although a relation between ovarian cancer mortality and obesitymore » has been previously established, a role of nesfatin-1 in ovarian epithelial carcinoma remains unknown. The aim of the present study is to examine the effect of nesfatin-1 on ovary carcinoma cells proliferation. We found that nesfatin-1 inhibits the proliferation and growth of HO-8910 cells by G1 phase arrest, this inhibition could be abolished by nesfatin-1 neutralizing antibody. Nesfatin-1 enhances HO-8910 cell apoptosis, activation of mammalian target of rapamycin (mTOR) and RhoA/ROCK signaling pathway block the effects of nesfatin-1-induced apoptosis, therefore reverses the inhibition of HO-8910 cell proliferation by nesfatin-1. In conclusion, the present study demonstrated that nesfatin-1 can inhibit the proliferation in human ovarian epithelial carcinoma cell line HO-8910 cells through inducing apoptosis via mTOR and RhoA/ROCK signaling pathway. This study provides a novel regulatory signaling pathway of nesfatin-1-regulated ovarian epithelial carcinoma growth and may contribute to ovarian cancer prevention and therapy, especially in obese patients.« less

  5. 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

  6. Cell cycles and proliferation patterns in Haematococcus pluvialis

    NASA Astrophysics Data System (ADS)

    Zhang, Chunhui; Liu, Jianguo; Zhang, Litao

    2017-09-01

    Most studies on Haematococcus pluvialis have been focused on cell growth and astaxanthin accumulation; far less attention has been paid to cell cycles and proliferation patterns. The purpose of this study was to clarify cell cycles and proliferation patterns in H. pluvialis microscopically using a camera and video recorder system. The complicated life history of H. pluvialis can be divided into two stages: the motile stage and the non-motile stage. All the cells can be classified into forms as follows: motile cell, nonmotile cell, zoospore and aplanospore. The main cell proliferation, both in the motile phase and non-motile phase in H. pluvialis, is by asexual reproduction. Under normal growth conditions, a motile cell usually produces two, sometimes four, and exceptionally eight zoospores. Under unfavorable conditions, the motile cell loses its flagella and transforms into a non-motile cell, and the non-motile cell usually produces 2, 4 or 8 aplanospores, and occasionally 20-32 aplanospores, which further develop into non-motile cells. Under suitable conditions, the non-motile cell is also able to release zoospores. The larger non-motile cells produce more than 16 zoospores, and the smaller ones produce 4 or 8 zoospores. Vegetative reproduction is by direct cell division in the motile phase and by occasional cell budding in the non-motile phase. There is, as yet, no convincing direct evidence for sexual reproduction.

  7. Stable chromosomal aberrations in haemopoietic stem cells in the blood of radiation accident victims.

    PubMed

    Kreja, L; Greulich, K M; Fliedner, T M; Heinze, B

    1999-10-01

    The detection of long-term persistent chromosome aberrations in circulating haemopoietic stem cells after accidental radiation exposure. Peripheral blood samples from highly exposed persons were collected 7-25 years after the radiation accidents in Moscow (1971), Kazan (1975) and Chernobyl (1996). Haemopoietic blood stem cells were analysed when investigating individual colonies derived from haemopoietic progenitor cells: burst-forming units-erythroid (BFU-E), granulocyte-macrophage-colony-forming cells (GM-CFC) and multipotent granulocyte-erythrocyte-macrophage- megakaryocyte-colony-forming cells (GEMM-CFC). Colony formation was obtained in methylcellulose cultures. Chromosome preparations in single colonies were performed using a microtechnique. Nine patients were investigated at 1 to 4 follow-up time points after radiation exposure. Three hundred and thirty-four single colonies were analyzed resulting in 1375 mitoses. It was found that colonies showed chromosome aberrations (ChA) up to 25 years after radiation exposure by classical cytogenetics and by fluorescence in situ hybridization (FISH). Stable aberrations were detected in 21% of colonies. They were clonal in 19% of colonies, i.e. the same abnormality was found in all cells derived from a single colony. In 2% of colonies ChA were stable but non-clonal; unstable ChA were not observed. The results indicate that blood-derived haemopoietic stem cells may serve as a biological indicator to detect radiation-induced ChA. Since they are considered to be in dynamic and functional exchange with stem cells in the medullary sites of blood cell formation such as bone marrow, the use of blood stem cells as a marker of radiation effects should be explored to assess the repair status of the stem cell pool as such.

  8. SOX15 regulates proliferation and migration of endometrial cancer cells.

    PubMed

    Rui, Xiaohui; Xu, Yun; Jiang, Xiping; Guo, Caixia; Jiang, Jingting

    2017-10-31

    The study aimed to investigate the effects of Sry-like high mobility group box 15 ( SOX15 ) on proliferation and migration of endometrial cancer (EC) cells. Immunohistochemistry (IHC) was applied to determine the expression of SOX15 in EC tissues and adjacent tissues. We used cell transfection method to construct the HEC-1-A and Ishikawa cell lines with stable overexpression and low expression SOX15 Reverse-transcription quantitative real-time PCR (RT-qPCR) and Western blot were performed to examine expression of SOX15 mRNA and SOX15 protein, respectively. By conducting a series of cell proliferation assay and migration assay, we analyzed the influence of SOX15 overexpression or low expression on EC cell proliferation and migration. The expression of SOX15 mRNA and protein in EC tissues was significantly lower than that in adjacent tissues. After lentivirus-transfecting SOX15 , the expression level of SOX15 mRNA and protein was significantly increased in cells of SOX15 group, and decreased in sh- SOX15 group. Overexpression of SOX15 could suppress cell proliferation, while down-regulation of SOX15 increased cell proliferation. Flow cytometry results indicated that overexpression of SOX15 induced the ratio of cell-cycle arrest in G 1 stage. In addition, Transwell migration assay results showed that SOX15 overexpression significantly inhibited cell migration, and also down-regulation of SOX15 promoted the migration. As a whole, SOX15 could regulate the proliferation and migration of EC cells and up- regulation of SOX15 could be valuable for EC treatment. © 2017 The Author(s).

  9. The geometry of proliferating dicot cells.

    PubMed

    Korn, R W

    2001-02-01

    The distributions of cell size and cell cycle duration were studied in two-dimensional expanding plant tissues. Plastic imprints of the leaf epidermis of three dicot plants, jade (Crassula argentae), impatiens (Impatiens wallerana), and the common begonia (Begonia semperflorens) were made and cell outlines analysed. The average, standard deviation and coefficient of variance (CV = 100 x standard deviation/average) of cell size were determined with the CV of mother cells less than the CV for daughter cells and both are less than that for all cells. An equation was devised as a simple description of the probability distribution of sizes for all cells of a tissue. Cell cycle durations as measured in arbitrary time units were determined by reconstructing the initial and final sizes of cells and they collectively give the expected asymmetric bell-shaped probability distribution. Given the features of unequal cell division (an average of 11.6% difference in size of daughter cells) and the size variation of dividing cells, it appears that the range of cell size is more critically regulated than the size of a cell at any particular time.

  10. Simulation of the Formation of DNA Double Strand Breaks and Chromosome Aberrations in Irradiated Cells

    NASA Technical Reports Server (NTRS)

    Plante, Ianik; Ponomarev, Artem L.; Wu, Honglu; Blattnig, Steve; George, Kerry

    2014-01-01

    The formation of DNA double-strand breaks (DSBs) and chromosome aberrations is an important consequence of ionizing radiation. To simulate DNA double-strand breaks and the formation of chromosome aberrations, we have recently merged the codes RITRACKS (Relativistic Ion Tracks) and NASARTI (NASA Radiation Track Image). The program RITRACKS is a stochastic code developed to simulate detailed event-by-event radiation track structure: [1] This code is used to calculate the dose in voxels of 20 nm, in a volume containing simulated chromosomes, [2] The number of tracks in the volume is calculated for each simulation by sampling a Poisson distribution, with the distribution parameter obtained from the irradiation dose, ion type and energy. The program NASARTI generates the chromosomes present in a cell nucleus by random walks of 20 nm, corresponding to the size of the dose voxels, [3] The generated chromosomes are located within domains which may intertwine, and [4] Each segment of the random walks corresponds to approx. 2,000 DNA base pairs. NASARTI uses pre-calculated dose at each voxel to calculate the probability of DNA damage at each random walk segment. Using the location of double-strand breaks, possible rejoining between damaged segments is evaluated. This yields various types of chromosomes aberrations, including deletions, inversions, exchanges, etc. By performing the calculations using various types of radiations, it will be possible to obtain relative biological effectiveness (RBE) values for several types of chromosome aberrations.

  11. Chromosomal Aberrations in DNA Repair Defective Cell Lines: Comparisons of Dose Rate and Radiation Quality

    NASA Technical Reports Server (NTRS)

    George, K. A.; Hada, M.; Patel, Z.; Huff, J.; Pluth, J. M.; Cucinotta, F. A.

    2009-01-01

    Chromosome aberration yields were assessed in DNA double-strand break repair (DSB) deficient cells after acute doses of gamma-rays or high-LET iron nuclei, or low dose-rate (0.018 Gy/hr) gamma-rays. We studied several cell lines including fibroblasts deficient in ATM (product of the gene that is mutated in ataxia telangiectasia patients) or NBS (product of the gene mutated in the Nijmegen breakage syndrome), and gliomablastoma cells that are proficient or lacking in DNA-dependent protein kinase, DNA-PK activity. Chromosomes were analyzed using the fluorescence in-situ hybridization (FISH) chromosome painting method in cells at the first division post-irradiation and chromosome aberrations were identified as either simple exchanges (translocations and dicentrics) or complex exchanges (involving >2 breaks in 2 or more chromosomes). Gamma radiation induced higher yields of both simple and complex exchanges in the DSB repair defective cells than in the normal cells. The quadratic dose-response terms for both chromosome exchange types were significantly higher for the ATM and NBS defective lines than for normal fibroblasts. However, the linear dose-response term was significantly higher only for simple exchanges in the NBS cells. Large increases in the quadratic dose response terms indicate the important roles of ATM and NBS in chromatin modifications that facilitate correct DSB repair and minimize aberration formation. Differences in the response of AT and NBS deficient cells at lower doses suggests important questions about the applicability of observations of radiation sensitivity at high dose to low dose exposures. For all iron nuclei irradiated cells, regression models preferred purely linear and quadratic dose responses for simple and complex exchanges, respectively. All the DNA repair defective cell lines had lower Relative biological effectiveness (RBE) values than normal cells, the lowest being for the DNA-PK-deficient cells, which was near unity. To further

  12. Eukaryotic initiation factor 5A-1 (eIF5A-1) as a diagnostic marker for aberrant proliferation in intraepithelial neoplasia of the vulva.

    PubMed

    Cracchiolo, Bernadette M; Heller, Debra S; Clement, Paul M J; Wolff, Edith C; Park, Myung-Hee; Hanauske-Abel, Hartmut M

    2004-07-01

    The mature eukaryotic translation initiation factor 5A contains the unusual amino acid hypusine, formed post-translationally from a specific lysine residue and essential for proliferation of eukaryotic cells. We hypothesized that the major eIF5A isoform, eIF5A-1, is an in situ biomarker for proliferation. NIH-353, a polyclonal immunoreagent specific for hypusine-containing eIF5A-1, was used to test this proposal in biopsies of vulvar high-grade intraepithelial neoplasia (VIN), characterized by the presence of proliferating cells throughout the thickness of the epithelium. Methods. Formalin-fixed and paraffin-embedded archival samples with an independently established diagnosis of VIN 3 were stained immunohistochemically after antigen retrieval, employing NIH-353 and, for comparison, the standard Ki-67 antibody. NIH-353 labeled neoplastic keratinocytes throughout the thickness of the epithelium in all VIN 3 samples. Malignant cells in a case of focally invasive squamous cell carcinoma also stained strongly for mature, hypusine-containing eIF5A-1. Epithelium adjacent to these lesions, though still of apparently normal morphology, was immunoreactive throughout its full thickness. At inflammatory foci of lesional sites, solitary reactive lymphocytes were positive, as were individual proliferating cells within dermal appendages. The submucosal stroma lacked reactive cells. NIH-353 identifies mature eIF5A-1 as an in situ biomarker for proliferation. Like Ki-67, this immunoreagent promises broad applicability in histopathological diagnosis and may be helpful in outcome prediction. In contrast to Ki-67, NIH-353 visualizes a molecular target for antineoplastic therapy, and thus may guide the development and clinical testing of drugs that, like the fungicide ciclopirox, inhibit hypusine formation and cell proliferation.

  13. Genomic and Epigenomic Aberrations in Esophageal Squamous Cell Carcinoma and Implications for Patients

    PubMed Central

    Lin, De-Chen; Wang, Ming-Rong; Koeffler, H. Phillip

    2018-01-01

    Esophageal squamous cell carcinoma (ESCC) is a common malignancy without effective therapy. The exomes of more than 600 ESCCs have been sequenced in the past 4 years, and numerous key aberrations have been identified. Recently, researchers reported both inter- and intratumor heterogeneity. Although these are interesting observations, their clinical implications are unclear due to the limited number of samples profiled. Epigenomic alterations, such as changes in DNA methylation, histone acetylation, and RNA editing, also have been observed in ESCCs. However, it is not clear what proportion of ESCC cells carry these epigenomic aberrations or how they contribute to tumor development. We review the genomic and epigenomic characteristics of ESCCs, with a focus on emerging themes. We discuss their clinical implications and future research directions. PMID:28757263

  14. The Endocrine Dyscrasia that Accompanies Menopause and Andropause Induces Aberrant Cell Cycle Signaling that Triggers Cell Cycle Reentry of Post-mitotic Neurons, Neurodysfunction, Neurodegeneration and Cognitive Disease

    PubMed Central

    Atwood, Craig S.; Bowen, Richard L.

    2016-01-01

    Sex hormones are the physiological factors that regulate neurogenesis during embryogenesis and continuing through adulthood. These hormones support the formation of brain structures such as dendritic spines, axons and synapses required for the capture of information (memories). Intriguingly, a recent animal study has demonstrated that induction of neurogenesis results in the loss of previously encoded memories in animals (e.g. infantile amnesia). In this connection, much evidence now indicates that Alzheimer’s disease (AD) also involves aberrant re-entry of post-mitotic neurons into the cell cycle. Cell cycle abnormalities appear very early in the disease, prior to the appearance of plaques and tangles, and explain the biochemical, neuropathological and cognitive changes observed with disease progression. Since sex hormones control when and how neurons proliferate and differentiate, the endocrine dyscrasia that accompanies menopause and andropause is a key signaling event that impacts neurogenesis and the acquisition, processing, storage and recall of memories. Here we review the biochemical, epidemiological and clinical evidence that alterations in endocrine signaling with menopause and andropause drive the aberrant re-entry of post-mitotic neurons into an abortive cell cycle with neurite retraction that leads to neuron dysfunction and death. When the reproductive axis is in balance, luteinizing hormone (LH), and its fetal homolog, human chorionic gonadotropin (hCG), promote pluripotent human and totipotent murine embryonic stem cell and neuron proliferation. However, strong evidence supports menopausal/andropausal elevations in the ratio of LH:sex steroids as driving aberrant mitotic events mediated by the upregulation of tumor necrosis factor, amyloid-β precursor protein processing towards the production of mitogenic Aβ, and the activation of Cdk5, a key regulator of cell cycle progression and tau phosphorylation (a cardinal feature of both neurogenesis and

  15. Gab3 is required for human colorectal cancer cell proliferation

    SciTech Connect

    Xiang, Shihao; Wang, Na; Hui, Pingping

    Here, we focused on the potential function of Gab3, an uncommon Gab family protein, in human colorectal cancer (CRC) cells. We found that Gab3 was only expressed in human colon cancer tissues as well as in established (HCT-116 and HT-29 lines) and primary human CRC cells. It was however absent in normal human colon cancer tissues and in FHC colon epithelial cells. Knockdown of Gab3 by targeted-shRNAs inhibited proliferation of the CRC cells. Reversely, exogenous over-expression of Gab3 promoted CRC cell proliferation. At the signaling level, Gab3 co-precipitated with p85 and SHP2 in CRC cells, which was required for subsequentmore » Akt and Erk activation. Gab3 shRNA knockdown inhibited Akt and Erk activation, yet Gab3 over-expression augmented it. In vivo, HCT-116 xenograft tumor growth in severe combined immune deficient (SCID) mice was suppressed following expressing Gab3 shRNAs. Meanwhile, Akt and Erk activation in Gab3 shRNA-expressing tumors was also largely inhibited. Together, our results suggest that Gab3 expression in CRC cells is important for Akt-Erk activation and cell proliferation. - Highlights: • Gab3 is only expressed in colorectal cancer (CRC) cells, but not in colon epithelial cells. • Gab3 shRNA knockdown inhibits CRC cell proliferation. • Exogenous over-expression of Gab3 promotes HCT-116 cell proliferation. • Gab3 co-precipitates with p85 and SHP2 to mediate Akt and Erk activation in CRC cells. • HCT-116 tumor growth in SCID mice is suppressed with expression of Gab3 shRNAs.« less

  16. The significance of PTEN and AKT aberrations in pediatric T-cell acute lymphoblastic leukemia

    PubMed Central

    Zuurbier, Linda; Petricoin, Emanuel F.; Vuerhard, Maartje J.; Calvert, Valerie; Kooi, Clarissa; Buijs-Gladdines, Jessica G.C.A.M.; Smits, Willem K.; Sonneveld, Edwin; Veerman, Anjo J.P.; Kamps, Willem A.; Horstmann, Martin; Pieters, Rob; Meijerink, Jules P.P.

    2012-01-01

    Background PI3K/AKT pathway mutations are found in T-cell acute lymphoblastic leukemia, but their overall impact and associations with other genetic aberrations is unknown. PTEN mutations have been proposed as secondary mutations that follow NOTCH1-activating mutations and cause cellular resistance to γ-secretase inhibitors. Design and Methods The impact of PTEN, PI3K and AKT aberrations was studied in a genetically well-characterized pediatric T-cell leukemia patient cohort (n=146) treated on DCOG or COALL protocols. Results PTEN and AKT E17K aberrations were detected in 13% and 2% of patients, respectively. Defective PTEN-splicing was identified in incidental cases. Patients without PTEN protein but lacking exon-, splice-, promoter mutations or promoter hypermethylation were present. PTEN/AKT mutations were especially abundant in TAL- or LMO-rearranged leukemia but nearly absent in TLX3-rearranged patients (P=0.03), the opposite to that observed for NOTCH1-activating mutations. Most PTEN/AKT mutant patients either lacked NOTCH1-activating mutations (P=0.006) or had weak NOTCH1-activating mutations (P=0.011), and consequently expressed low intracellular NOTCH1, cMYC and MUSASHI levels. T-cell leukemia patients without PTEN/AKT and NOTCH1-activating mutations fared well, with a cumulative incidence of relapse of only 8% versus 35% for PTEN/AKT and/or NOTCH1-activated patients (P=0.005). Conclusions PI3K/AKT pathway aberrations are present in 18% of pediatric T-cell acute lymphoblastic leukemia patients. Absence of strong NOTCH1-activating mutations in these cases may explain cellular insensitivity to γ-secretase inhibitors. PMID:22491738

  17. Gene Targets in Prostate Tumor Cells that Mediate Aberrant Growth and Invasiveness

    DTIC Science & Technology

    2005-02-01

    Craig A. Hauser , Ph.D. Gabriele Foos, Ph.D. CONTRACTING ORGANIZATION: The Burnham Institute La Jolla, California 92037 REPORT DATE: February 2005 TYPE...NUMBERS Gene Targets in Prostate Tumor Cells that Mediate DAMD17-02-1-0019 Aberrant Growth and Invasiveness 6. AUTHOR(S) Craig A. Hauser , Ph.D. Gabriele...REPORTABLE OUTCOMES Foos G, Hauser CA (2004) The role of Ets transcription factors in mediating cellular transformation. In: Handbook of Experimental

  18. Painting Analysis of Chromosome Aberrations Induced by Energetic Heavy Ions in Human Cells

    NASA Technical Reports Server (NTRS)

    Wu, Honglu; Hada, Megumi; Cucinotta, Francis

    2007-01-01

    This viewgraph presentation reviews some of the techniques used to analyze the damage done to chromosome from ion radiation. Fluorescence in situ hybridization (FISH), mFISH, mBAND, telomere and centromereprobes have been used to study chromosome aberrations induced in human cells exposed to low-and high-LET radiation in vitro. There is some comparison of the different results from the various techniques. The results of the study are summarized.

  19. MAPK/ERK2 phosphorylates ERG at serine 283 in leukemic cells and promotes stem cell signatures and cell proliferation

    PubMed Central

    Huang, Y; Thoms, JAI; Tursky, ML; Knezevic, K; Beck, D; Chandrakanthan, V; Suryani, S; Olivier, J; Boulton, A; Glaros, EN; Thomas, SR; Lock, RB; MacKenzie, KL; Bushweller, JH; Wong, JWH; Pimanda, JE

    2018-01-01

    Aberrant ERG (v-ets avian erythroblastosis virus E26 oncogene homolog) expression drives leukemic transformation in mice and high expression is associated with poor patient outcomes in acute myeloid leukemia (AML) and T-acute lymphoblastic leukemia (T-ALL). Protein phosphorylation regulates the activity of many ETS factors but little is known about ERG in leukemic cells. To characterize ERG phosphorylation in leukemic cells, we applied liquid chromatography coupled tandem mass spectrometry and identified five phosphorylated serines on endogenous ERG in T-ALL and AML cells. S283 was distinct as it was abundantly phosphorylated in leukemic cells but not in healthy hematopoietic stem and progenitor cells (HSPCs). Overexpression of a phosphoactive mutant (S283D) increased expansion and clonogenicity of primary HSPCs over and above wild-type ERG. Using a custom antibody, we screened a panel of primary leukemic xenografts and showed that ERG S283 phosphorylation was mediated by mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) signaling and in turn regulated expression of components of this pathway. S283 phosphorylation facilitates ERG enrichment and transactivation at the ERG +85 HSPC enhancer that is active in AML and T-ALL with poor prognosis. Taken together, we have identified a specific post-translational modification in leukemic cells that promotes progenitor proliferation and is a potential target to modulate ERG-driven transcriptional programs in leukemia. PMID:27055868

  20. Cell surface GRP78 facilitates hepatoma cells proliferation and migration by activating IGF-IR.

    PubMed

    Yin, Yancun; Chen, Chen; Chen, Jinliang; Zhan, Renhui; Zhang, Qiang; Xu, Xiaoyan; Li, Defang; Li, Minjing

    2017-07-01

    The 78kDa glucose regulated protein (GRP78) is a multifunctional chaperone that is involved in a variety of cellular processes. Insulin like growth factor I receptor (IGF-IR) often aberrant expresses in many types of tumor cells. The IGF-IR signaling plays key roles in carcinogenesis and maintenance of the malignant phenotype. The crosstalk between GRP78 and IGF-IR molecules has not well been illuminated. Here, we demonstrated a reciprocal regulation of GRP78 expression and IGF-IR pathway activation. IGF-I induced GRP78 expression in hepatoma cells. IGF-IR knockdown or IGF-IR inhibitor repressed GRP78 expression. Both phosphatidylinositol 3-kianase (PI3K) and mitogen-activated protein kinase (MAPK) pathways involved in IGF-I induction of GRP78 expression. Interestingly, treatment of hepatoma cells with IGF-I re-distributes GRP78 from endoplasmic reticulum (ER) to cell surface and promotes its physical interaction with IGF-IR. Also, GRP78 promotes IGF-IR phosphorylation and activation. Blocked of GRP78 by small interfering RNA or inhibition of GRP78 function by (-)-epigallocatechin gallate (EGCG) blocks IGF-I induced IGF-IR phosphorylation and its downstream signaling. Further, blocked cell surface GRP78 with antibody inhibits IGF-I stimulated cellular proliferation and migration. These data reveal an essential role for the molecular chaperone GRP78 in IGF-IR signaling and implicate the use of GRP78 inhibitors in blocking IGF-IR signaling in hepatoma cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Aerobic glycolysis: meeting the metabolic requirements of cell proliferation.

    PubMed

    Lunt, Sophia Y; Vander Heiden, Matthew G

    2011-01-01

    Warburg's observation that cancer cells exhibit a high rate of glycolysis even in the presence of oxygen (aerobic glycolysis) sparked debate over the role of glycolysis in normal and cancer cells. Although it has been established that defects in mitochondrial respiration are not the cause of cancer or aerobic glycolysis, the advantages of enhanced glycolysis in cancer remain controversial. Many cells ranging from microbes to lymphocytes use aerobic glycolysis during rapid proliferation, which suggests it may play a fundamental role in supporting cell growth. Here, we review how glycolysis contributes to the metabolic processes of dividing cells. We provide a detailed accounting of the biosynthetic requirements to construct a new cell and illustrate the importance of glycolysis in providing carbons to generate biomass. We argue that the major function of aerobic glycolysis is to maintain high levels of glycolytic intermediates to support anabolic reactions in cells, thus providing an explanation for why increased glucose metabolism is selected for in proliferating cells throughout nature.

  2. Myostatin inhibits proliferation of human urethral rhabdosphincter satellite cells.

    PubMed

    Akita, Yasuyuki; Sumino, Yasuhiro; Mori, Ken-ichi; Nomura, Takeo; Sato, Fuminori; Mimata, Hiromitsu

    2013-05-01

    Myostatin, a member of the transforming growth factor-β superfamily, is a negative regulator of myogenesis in skeletal muscle. We examined the effect of myostatin and myostatin inhibition by an antagonistic agent, follistatin, on growth of human urethral rhabdosphincter satellite cells (muscle stem cells) to develop a new strategy for treatment of stress urinary incontinence. Rhabdosphincter satellite cells were cultured and selected by magnetic affinity cell sorting using an anti-neural cell adhesion molecule antibody. The cells were transfected with simian virus-40 antigen to extend their lifespan. A cell proliferation assay, a cell cycle analysis and an investigation of signal transduction were carried out. The autocrine action of endogenous myostatin by western blotting, real-time reverse transcription polymerase chain reaction and immunoneutralization using an anti-myostatin antibody was also evaluated. Selectively cultured cells expressed markers of striated muscles and successfully differentiated into myotubes. Myostatin inhibited proliferation of these cells through Smad2 phosphorylation and cell cycle arrest. Inhibitory effects of myostatin were reversed by addition of follistatin. However, rhabdosphincter satellite cells did not appear to use autocrine secretion of myostatin to regulate their proliferation. Inhibition of myostatin function might be a useful pathway in the development of novel strategies for stimulating rhabdosphincter cells regeneration to treat stress urinary incontinence. © 2012 The Japanese Urological Association.

  3. RBE of Energetic Iron Ions for the Induction of Early and Late Chromosome Aberrations in Different Cell Types

    NASA Technical Reports Server (NTRS)

    Zhang, Ye; Yeshitla, Samrawit; Hada, Megumi; Kadhim, Munira; Wilson, Bobby; Wu, Honglu

    2015-01-01

    Numerous published studies have reported the Relative Biological Effectiveness (RBE) values for chromosome aberrations induced by charged particles of different LET. The RBE for chromosome aberrations in human lymphocytes exposed ex vivo has been suggested to show a similar relationship as the quality factor for cancer induction. Therefore, increased chromosome aberrations in the astronauts' white blood cells post long-duration missions are used to determine the biological doses from exposures to space radiation. However, the RBE value is known to be very different for different types of cancer. Previously, we reported that, even though the RBE for initial chromosome damages was high in human lymphocytes exposed to Fe ions, the RBE was significantly reduced after multiple cell divisions post irradiation. To test the hypothesis that RBE values for chromosome aberrations are cell type dependent, and different between early and late damages, we exposed human lymphocytes ex vivo, and human mammary epithelial cells in vitro to various charged particles. Chromosome aberrations were quantified using the samples collected at first mitosis post irradiation for initial damages, and the samples collected after multiple generations for the remaining or late arising aberrations. Results of the study suggested that the effectiveness of high-LET charged particles for late chromosome aberrations may be cell type dependent, even though the RBE values are similar for early damages.

  4. Targeting HER2 Aberrations in Non-Small Cell Lung Cancer with Osimertinib.

    PubMed

    Liu, Shengwu; Li, Shuai; Hai, Josephine; Wang, Xiaoen; Chen, Ting; Quinn, Max M; Gao, Peng; Zhang, Yanxi; Ji, Hongbin; Cross, Darren A E; Wong, Kwok-Kin

    2018-01-03

    Purpose: HER2 (or ERBB2 ) aberrations, including both amplification and mutations, have been classified as oncogenic drivers that contribute to 2% to 6% of lung adenocarcinomas. HER2 amplification is also an important mechanism for acquired resistance to EGFR tyrosine kinase inhibitors (TKI). However, due to limited preclinical studies and clinical trials, currently there is still no available standard of care for lung cancer patients with HER2 aberrations. To fulfill the clinical need for targeting HER2 in patients with non-small cell lung cancer (NSCLC), we performed a comprehensive preclinical study to evaluate the efficacy of a third-generation TKI, osimertinib (AZD9291). Experimental Design: Three genetically modified mouse models (GEMM) mimicking individual HER2 alterations in NSCLC were generated, and osimertinib was tested for its efficacy against these HER2 aberrations in vivo Results: Osimertinib treatment showed robust efficacy in HER2 wt overexpression and EGFR del19/HER2 models, but not in HER2 exon 20 insertion tumors. Interestingly, we further identified that combined treatment with osimertinib and the BET inhibitor JQ1 significantly increased the response rate in HER2 -mutant NSCLC, whereas JQ1 single treatment did not show efficacy. Conclusions: Overall, our data indicated robust antitumor efficacy of osimertinib against multiple HER2 aberrations in lung cancer, either as a single agent or in combination with JQ1. Our study provides a strong rationale for future clinical trials using osimertinib either alone or in combination with epigenetic drugs to target aberrant HER2 in patients with NSCLC. Clin Cancer Res; 24(11); 1-11. ©2018 AACR. See related commentary by Cappuzzo and Landi, p. 2470 . ©2018 American Association for Cancer Research.

  5. Stepwise DNA Methylation Changes Are Linked to Escape from Defined Proliferation Barriers and Mammary Epithelial Cell Immortalization

    SciTech Connect

    Novak, Petr; Jensen, Taylor J.; Garbe, James C.

    The timing and progression of DNA methylation changes during carcinogenesis are not completely understood. To develop a timeline of aberrant DNA methylation events during malignant transformation, we analyzed genome-wide DNA methylation patterns in an isogenic human mammary epithelial cell (HMEC) culture model of transformation. To acquire immortality and malignancy, the cultured finite lifespan HMEC must overcome two distinct proliferation barriers. The first barrier, stasis, is mediated by the retinoblastoma protein and can be overcome by loss of p16(INK4A) expression. HMEC that escape stasis and continue to proliferate become genomically unstable before encountering a second more stringent proliferation barrier, telomere dysfunctionmore » due to telomere attrition. Rare cells that acquire telomerase expression may escape this barrier, become immortal, and develop further malignant properties. Our analysis of HMEC transitioning from finite lifespan to malignantly transformed showed that aberrant DNA methylation changes occur in a stepwise fashion early in the transformation process. The first aberrant DNA methylation step coincides with overcoming stasis, and results in few to hundreds of changes, depending on how stasis was overcome. A second step coincides with immortalization and results in hundreds of additional DNA methylation changes regardless of the immortalization pathway. A majority of these DNA methylation changes are also found in malignant breast cancer cells. These results show that large-scale epigenetic remodeling occurs in the earliest steps of mammary carcinogenesis, temporally links DNA methylation changes and overcoming cellular proliferation barriers, and provides a bank of potential epigenetic biomarkers that mayprove useful in breast cancer risk assessment.« less

  6. TESTIN Induces Rapid Death and Suppresses Proliferation in Childhood B Acute Lymphoblastic Leukaemia Cells

    PubMed Central

    Weeks, Robert J.; Ludgate, Jackie L.; LeMée, Gwenn; Morison, Ian M.

    2016-01-01

    Background Childhood acute lymphoblastic leukaemia (ALL) is the most common malignancy in children. Despite high cure rates, side effects and late consequences of the intensive treatments are common. Unquestionably, the identification of new therapeutic targets will lead to safer, more effective treatments. We identified TES promoter methylation and transcriptional silencing as a very common molecular abnormality in childhood ALL, irrespective of molecular subtype. The aims of the present study were to demonstrate that TES promoter methylation is aberrant, to determine the effects of TES re-expression in ALL, and to determine if those effects are mediated via TP53 activity. Methods Normal fetal and adult tissue DNA was isolated and TES promoter methylation determined by Sequenom MassARRAY. Quantitative RT-PCR and immunoblot were used to confirm re-expression of TES in ALL cell lines after 5’-aza-2’-deoxycytidine (decitabine) exposure or transfection with TES expression plasmids. The effects of TES re-expression on ALL cells were investigated using standard cell proliferation, cell death and cell cycle assays. Results In this study, we confirm that the TES promoter is unmethylated in normal adult and fetal tissues. We report that decitabine treatment of ALL cell lines results in demethylation of the TES promoter and attendant expression of TES mRNA. Re-expression of TESTIN protein in ALL cells using expression plasmid transfection results in rapid cell death or cell cycle arrest independent of TP53 activity. Conclusions These results suggest that TES is aberrantly methylated in ALL and that re-expression of TESTIN has anti-leukaemia effects which point to novel therapeutic opportunities for childhood ALL. PMID:26985820

  7. Dependence of Early and Late Chromosomal Aberrations on Radiation Quality and Cell Types

    NASA Technical Reports Server (NTRS)

    Lu, Tao; Zhang, Ye; Krieger, Stephanie; Yeshitla, Samrawit; Goss, Rosalin; Bowler, Deborah; Kadhim, Munira; Wilson, Bobby; Rohde, Larry; Wu, Honglu

    2017-01-01

    Exposure to radiation induces different types of DNA damage, increases mutation and chromosome aberration rates, and increases cellular transformation in vitro and in vivo. The susceptibility of cells to radiation depends on genetic background and growth condition of cells, as well as types of radiation. Mammalian cells of different tissue types and with different genetic background are known to have different survival rate and different mutation rate after cytogenetic insults. Genomic instability, induced by various genetic, metabolic, and environmental factors including radiation, is the driving force of tumorigenesis. Accurate measurements of the relative biological effectiveness (RBE) is important for estimating radiation-related risks. To further understand genomic instability induced by charged particles and their RBE, we exposed human lymphocytes ex vivo, human fibroblast AG1522, human mammary epithelial cells (CH184B5F5/M10), and bone marrow cells isolated from CBA/CaH(CBA) and C57BL/6 (C57) mice to high energy protons and Fe ions. Normal human fibroblasts AG1522 have apparently normal DNA damage response and repair mechanisms, while mammary epithelial cells (M10) are deficient in the repair of DNA DSBs. Mouse strain CBA is radio-sensitive while C57 is radio-resistant. Metaphase chromosomes at different cell divisions after radiation exposure were collected and chromosome aberrations were analyzed as RBE for different cell lines exposed to different radiations at various time points up to one month post irradiation.

  8. Jab1 regulates Schwann cell proliferation and axonal sorting through p27

    PubMed Central

    Porrello, Emanuela; Rivellini, Cristina; Dina, Giorgia; Triolo, Daniela; Del Carro, Ubaldo; Ungaro, Daniela; Panattoni, Martina; Feltri, Maria Laura; Wrabetz, Lawrence; Pardi, Ruggero; Quattrini, Angelo

    2014-01-01

    Axonal sorting is a crucial event in nerve formation and requires proper Schwann cell proliferation, differentiation, and contact with axons. Any defect in axonal sorting results in dysmyelinating peripheral neuropathies. Evidence from mouse models shows that axonal sorting is regulated by laminin211– and, possibly, neuregulin 1 (Nrg1)–derived signals. However, how these signals are integrated in Schwann cells is largely unknown. We now report that the nuclear Jun activation domain–binding protein 1 (Jab1) may transduce laminin211 signals to regulate Schwann cell number and differentiation during axonal sorting. Mice with inactivation of Jab1 in Schwann cells develop a dysmyelinating neuropathy with axonal sorting defects. Loss of Jab1 increases p27 levels in Schwann cells, which causes defective cell cycle progression and aberrant differentiation. Genetic down-regulation of p27 levels in Jab1-null mice restores Schwann cell number, differentiation, and axonal sorting and rescues the dysmyelinating neuropathy. Thus, Jab1 constitutes a regulatory molecule that integrates laminin211 signals in Schwann cells to govern cell cycle, cell number, and differentiation. Finally, Jab1 may constitute a key molecule in the pathogenesis of dysmyelinating neuropathies. PMID:24344238

  9. Electrospun fiber membranes enable proliferation of genetically modified cells

    PubMed Central

    Borjigin, Mandula; Eskridge, Chris; Niamat, Rohina; Strouse, Bryan; Bialk, Pawel; Kmiec, Eric B

    2013-01-01

    Polycaprolactone (PCL) and its blended composites (chitosan, gelatin, and lecithin) are well-established biomaterials that can enrich cell growth and enable tissue engineering. However, their application in the recovery and proliferation of genetically modified cells has not been studied. In the study reported here, we fabricated PCL-biomaterial blended fiber membranes, characterized them using physicochemical techniques, and used them as templates for the growth of genetically modified HCT116-19 colon cancer cells. Our data show that the blended polymers are highly miscible and form homogenous electrospun fiber membranes of uniform texture. The aligned PCL nanofibers support robust cell growth, yielding a 2.5-fold higher proliferation rate than cells plated on standard plastic plate surfaces. PCL-lecithin fiber membranes yielded a 2.7-fold higher rate of proliferation, while PCL-chitosan supported a more modest growth rate (1.5-fold higher). Surprisingly, PCL-gelatin did not enhance cell proliferation when compared to the rate of cell growth on plastic surfaces. PMID:23467983

  10. Intermittent individual housing increases survival of newly proliferated cells.

    PubMed

    Aberg, Elin; Pham, Therese M; Zwart, Mieke; Baumans, Vera; Brené, Stefan

    2005-09-08

    In this study, we analyzed how intermittent individual housing with or without a running wheel influenced corticosterone levels and survival of newly proliferated cells in the dentate gyrus of the hippocampus. Female Balb/c mice, in standard or enhanced housing, were divided into groups that were individually housed with or without running wheels on every second day. Intermittent individual housing without, but not with, running wheels increased survival of proliferated cells in the dentate gyrus as compared with continuous group housing in standard or enhanced conditions. Thus, changes in housing conditions on every second day can, under certain circumstances, have an impact on the survival of newly proliferated cells in the dentate gyrus.

  11. Automated measurement of cell motility and proliferation

    PubMed Central

    Bahnson, Alfred; Athanassiou, Charalambos; Koebler, Douglas; Qian, Lei; Shun, Tongying; Shields, Donna; Yu, Hui; Wang, Hong; Goff, Julie; Cheng, Tao; Houck, Raymond; Cowsert, Lex

    2005-01-01

    Background Time-lapse microscopic imaging provides a powerful approach for following changes in cell phenotype over time. Visible responses of whole cells can yield insight into functional changes that underlie physiological processes in health and disease. For example, features of cell motility accompany molecular changes that are central to the immune response, to carcinogenesis and metastasis, to wound healing and tissue regeneration, and to the myriad developmental processes that generate an organism. Previously reported image processing methods for motility analysis required custom viewing devices and manual interactions that may introduce bias, that slow throughput, and that constrain the scope of experiments in terms of the number of treatment variables, time period of observation, replication and statistical options. Here we describe a fully automated system in which images are acquired 24/7 from 384 well plates and are automatically processed to yield high-content motility and morphological data. Results We have applied this technology to study the effects of different extracellular matrix compounds on human osteoblast-like cell lines to explore functional changes that may underlie processes involved in bone formation and maintenance. We show dose-response and kinetic data for induction of increased motility by laminin and collagen type I without significant effects on growth rate. Differential motility response was evident within 4 hours of plating cells; long-term responses differed depending upon cell type and surface coating. Average velocities were increased approximately 0.1 um/min by ten-fold increases in laminin coating concentration in some cases. Comparison with manual tracking demonstrated the accuracy of the automated method and highlighted the comparative imprecision of human tracking for analysis of cell motility data. Quality statistics are reported that associate with stage noise, interference by non-cell objects, and uncertainty in the

  12. Development of bioengineering system for stem cell proliferation

    NASA Astrophysics Data System (ADS)

    Park, H. S.; Shah, R.; Shah, C.

    2016-08-01

    From last decades, intensive research in the field of stem cells proliferation had been promoted due to the unique property of stem cells to self-renew themselves into multiples and has potential to replicate into an organ or tissues and so it's highly demanding though challenging. Bioreactor, a mechanical device, works as a womb for stem cell proliferation by providing nutritious environment for the proper growth of stem cells. Various factors affecting stem cells growth are the bioreactor mechanism, feeding of continuous nutrients, healthy environment, etc., but it always remains a challenge for controlling biological parameters. The present paper unveils the design of mechanical device commonly known as bioreactor in tissues engineering and biotech field, use for proliferation of stem cells and imparts the proper growing condition for stem cells. This high functional bioreactor provides automation mixing of cell culture and stem cells. This design operates in conjunction with mechanism of reciprocating motion. Compare to commercial bioreactors, this proposed design is more convenient, easy to operate and less maintenance is required as bioreactor culture bag is made of polyethylene which is single use purpose. Development of this bioengineering system will be beneficial for better growth and expansion of stem cell

  13. Click Chemistry for Analysis of Cell Proliferation in Flow Cytometry.

    PubMed

    Clarke, Scott T; Calderon, Veronica; Bradford, Jolene A

    2017-10-02

    The measurement of cellular proliferation is fundamental to the assessment of cellular health, genotoxicity, and the evaluation of drug efficacy. Labeling, detection, and quantification of cells in the synthesis phase of cell cycle progression are not only important for characterizing basic biology, but also in defining cellular responses to drug treatments. Changes in DNA replication during S-phase can provide valuable insights into mechanisms of cell growth, cell cycle kinetics, and cytotoxicity. A common method for detection of cell proliferation is the incorporation of a thymidine analog during DNA synthesis. This chapter presents a pulse labeling method using the thymidine analog, 5-ethynyl-2'-deoxyuridine (EdU), with subsequent detection by click chemistry. EdU detection using click chemistry is bio-orthogonal to most living systems and does not non-specifically label other biomolecules. Live cells are first pulsed with EdU. After antibody labeling cell surface markers, fixation, and permeabilization, the incorporated EdU is covalently labeled using click chemistry thereby identifying proliferating cells. Improvements in click chemistry allow for labeling in the presence of fluorescent proteins and phycobiliproteins without quenching due to copper. Measuring DNA replication during cell cycle progression has cell health applications in flow cytometry, fluorescence microscopy, and high content imaging. This protocol has been developed and optimized for research use only and is not suitable for use in diagnostic procedures. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

  14. Role of Dicer1 in thyroid cell proliferation and differentiation.

    PubMed

    Penha, Ricardo Cortez Cardoso; Sepe, Romina; De Martino, Marco; Esposito, Francesco; Pellecchia, Simona; Raia, Maddalena; Del Vecchio, Luigi; Decaussin-Petrucci, Myriam; De Vita, Gabriella; Pinto, Luis Felipe Ribeiro; Fusco, Alfredo

    2017-01-01

    DICER1 plays a central role in the biogenesis of microRNAs and it is important for normal development. Altered microRNA expression and DICER1 dysregulation have been described in several types of tumors, including thyroid carcinomas. Recently, our group identified a new somatic mutation (c.5438A>G; E1813G) within DICER1 gene of an unknown function. Herein, we show that DICER1 is overexpressed, at mRNA level, in a significant-relative number of papillary (70%) and anaplastic (42%) thyroid carcinoma samples, whereas is drastically downregulated in all the analyzed human thyroid carcinoma cell lines (TPC-1, BCPAP, FRO and 8505c) in comparison with normal thyroid tissue samples. Conversely, DICER1 is downregulated, at protein level, in PTC in comparison with normal thyroid tissues. Our data also reveals that DICER1 overexpression positively regulates thyroid cell proliferation, whereas its silencing impairs thyroid cell differentiation. The expression of DICER1 gene mutation (c.5438A>G; E1813G) negatively affects the microRNA machinery and cell proliferation as well as upregulates DICER1 protein levels of thyroid cells but has no impact on thyroid differentiation. In conclusion, DICER1 protein is downregulated in papillary thyroid carcinomas and affects thyroid proliferation and differentiation, while DICER1 gene mutation (c.5438A>G; E1813G) compromises the DICER1 wild-type-mediated microRNA processing and cell proliferation.

  15. Sildenafil Inhibits the Proliferation of Cultured Human Endothelial Cells

    PubMed Central

    Erdogan, Ali; Luedders, Doerte Wiebke; Muenz, Benedikt Manuel; Schaefer, Christian Alexander; Tillmanns, Harald; Wiecha, Johannes; Kuhlmann, Christoph Ruediger Wolfram

    2007-01-01

    The proliferation of endothelial cells plays a crucial role in the development of intraplaque angiogenesis (IPA). IPA is a major source of intraplaque hemorrhage and therefore contributes to the destabilization of atherosclerotic plaques. Therefore, the aim of the present study was to examine, whether sildenafil inhibits endothelial cell growth. The proliferation of human endothelial cells derived from umbilical cord veins (HUVEC) was examined on DNA level by measurements of (3H)-thymidine incorporation. Cell viability was analyzed using trypan blue staining. The proliferation of cultured human endothelial cells was significantly decreased by 1 μmol/l (-48.4%) and 10 μmol/l (-89.6%) sildenafil (n=10, p<0.05). This was not a cytotoxic effect, because cell viability was only reduced at sildenafil concentrations of 50 μmol/l or greater. In addition sildenafil significantly reduced endothelial proliferation induced by bFGF (n=10, p<0.05). The presented results demonstrate an antiangiogenic effect of sildenafil that might be useful in the prevention of atherosclerotic plaque vascularization. PMID:23675029

  16. Aldosterone Promotes Cardiac Endothelial Cell Proliferation In Vivo

    PubMed Central

    Gravez, Basile; Tarjus, Antoine; Pelloux, Véronique; Ouvrard‐Pascaud, Antoine; Delcayre, Claude; Samuel, Janelise; Clément, Karine; Farman, Nicolette; Jaisser, Fréderic; Messaoudi, Smail

    2015-01-01

    Background Experimentally, aldosterone in association with NaCl induces cardiac fibrosis, oxidative stress, and inflammation through mineralocorticoid receptor activation; however, the biological processes regulated by aldosterone alone in the heart remain to be identified. Methods and Results Mice were treated for 7 days with aldosterone, and then cardiac transcriptome was analyzed. Aldosterone regulated 60 transcripts (51 upregulated and 9 downregulated) in the heart (fold change ≥1.5, false discovery rate <0.01). To identify the biological processes modulated by aldosterone, a gene ontology analysis was performed. The majority of aldosterone‐regulated genes were involved in cell division. The cardiac Ki‐67 index (an index of proliferation) of aldosterone‐treated mice was higher than that of nontreated mice, confirming microarray predictions. Costaining of Ki‐67 with vinculin, CD68, α‐smooth muscle actin, CD31, or caveolin 1 revealed that the cycling cells were essentially endothelial cells. Aldosterone‐induced mineralocorticoid receptor–dependent proliferation was confirmed ex vivo in human endothelial cells. Moreover, pharmacological‐specific blockade of mineralocorticoid receptor by eplerenone inhibited endothelial cell proliferation in a preclinical model of heart failure (transverse aortic constriction). Conclusions Aldosterone modulates cardiac gene expression and induces the proliferation of cardiac endothelial cells in vivo. PMID:25564371

  17. Tyrosine kinase receptor c-ros-oncogene 1 inhibition alleviates aberrant bone formation of TWIST-1 haploinsufficient calvarial cells from Saethre-Chotzen syndrome patients.

    PubMed

    Camp, Esther; Anderson, Peter J; Zannettino, Andrew C W; Glackin, Carlotta A; Gronthos, Stan

    2018-09-01

    Saethre-Chotzen syndrome (SCS), associated with TWIST-1 mutations, is characterized by premature fusion of cranial sutures. TWIST-1 haploinsufficiency, leads to alterations in suture mesenchyme cellular gene expression patterns, resulting in aberrant osteogenesis and craniosynostosis. We analyzed the expression of the TWIST-1 target, Tyrosine kinase receptor c-ros-oncogene 1 (C-ROS-1) in TWIST-1 haploinsufficient calvarial cells derived from SCS patients and calvaria of Twist-1 del/+ mutant mice and found it to be highly expressed when compared to TWIST-1 wild-type controls. Knock-down of C-ROS-1 expression in TWIST-1 haploinsufficient calvarial cells derived from SCS patients was associated with decreased capacity for osteogenic differentiation in vitro. Furthermore, treatment of human SCS calvarial cells with the tyrosine kinase chemical inhibitor, Crizotinib, resulted in reduced C-ROS-1 activity and the osteogenic potential of human SCS calvarial cells with minor effects on cell viability or proliferation. Cultured human SCS calvarial cells treated with Crizotinib exhibited a dose-dependent decrease in alkaline phosphatase activity and mineral deposition, with an associated decrease in expression levels of Runt-related transcription factor 2 and OSTEOPONTIN, with reduced PI3K/Akt signalling in vitro. Furthermore, Crizotinib treatment resulted in reduced BMP-2 mediated bone formation potential of whole Twist-1 del/+ mutant mouse calvaria organotypic cultures. Collectively, these results suggest that C-ROS-1 promotes osteogenic differentiation of TWIST-1 haploinsufficient calvarial osteogenic progenitor cells. Furthermore, the aberrant osteogenic potential of these cells is inhibited by the reduction of C-ROS-1. Therefore, targeting C-ROS-1 with a pharmacological agent, such as Crizotinib, may serve as a novel therapeutic strategy to alleviate craniosynostosis associated with aberrant TWIST-1 function. © 2018 Wiley Periodicals, Inc.

  18. Aberrantly Expressed OTX Homeobox Genes Deregulate B-Cell Differentiation in Hodgkin Lymphoma.

    PubMed

    Nagel, Stefan; Ehrentraut, Stefan; Meyer, Corinna; Kaufmann, Maren; Drexler, Hans G; MacLeod, Roderick A F

    2015-01-01

    In Hodgkin lymphoma (HL) we recently reported that deregulated homeobox gene MSX1 mediates repression of the B-cell specific transcription factor ZHX2. In this study we investigated regulation of MSX1 in this B-cell malignancy. Accordingly, we analyzed expression and function of OTX homeobox genes which activate MSX1 transcription during embryonal development in the neural plate border region. Our data demonstrate that OTX1 and OTX2 are aberrantly expressed in both HL patients and cell lines. Moreover, both OTX loci are targeted by genomic gains in overexpressing cell lines. Comparative expression profiling and subsequent pathway modulations in HL cell lines indicated that aberrantly enhanced FGF2-signalling activates the expression of OTX2. Downstream analyses of OTX2 demonstrated transcriptional activation of genes encoding transcription factors MSX1, FOXC1 and ZHX1. Interestingly, examination of the physiological expression profile of ZHX1 in normal hematopoietic cells revealed elevated levels in T-cells and reduced expression in B-cells, indicating a discriminatory role in lymphopoiesis. Furthermore, two OTX-negative HL cell lines overexpressed ZHX1 in correlation with genomic amplification of its locus at chromosomal band 8q24, supporting the oncogenic potential of this gene in HL. Taken together, our data demonstrate that deregulated homeobox genes MSX1 and OTX2 respectively impact transcriptional inhibition of (B-cell specific) ZHX2 and activation of (T-cell specific) ZHX1. Thus, we show how reactivation of a specific embryonal gene regulatory network promotes disturbed B-cell differentiation in HL.

  19. 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.

  20. 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

  1. The cell proliferation antigen Ki-67 organises heterochromatin

    PubMed Central

    Sobecki, Michal; Mrouj, Karim; Camasses, Alain; Parisis, Nikolaos; Nicolas, Emilien; Llères, David; Gerbe, François; Prieto, Susana; Krasinska, Liliana; David, Alexandre; Eguren, Manuel; Birling, Marie-Christine; Urbach, Serge; Hem, Sonia; Déjardin, Jérôme; Malumbres, Marcos; Jay, Philippe; Dulic, Vjekoslav; Lafontaine, Denis LJ; Feil, Robert; Fisher, Daniel

    2016-01-01

    Antigen Ki-67 is a nuclear protein expressed in proliferating mammalian cells. It is widely used in cancer histopathology but its functions remain unclear. Here, we show that Ki-67 controls heterochromatin organisation. Altering Ki-67 expression levels did not significantly affect cell proliferation in vivo. Ki-67 mutant mice developed normally and cells lacking Ki-67 proliferated efficiently. Conversely, upregulation of Ki-67 expression in differentiated tissues did not prevent cell cycle arrest. Ki-67 interactors included proteins involved in nucleolar processes and chromatin regulators. Ki-67 depletion disrupted nucleologenesis but did not inhibit pre-rRNA processing. In contrast, it altered gene expression. Ki-67 silencing also had wide-ranging effects on chromatin organisation, disrupting heterochromatin compaction and long-range genomic interactions. Trimethylation of histone H3K9 and H4K20 was relocalised within the nucleus. Finally, overexpression of human or Xenopus Ki-67 induced ectopic heterochromatin formation. Altogether, our results suggest that Ki-67 expression in proliferating cells spatially organises heterochromatin, thereby controlling gene expression. DOI: http://dx.doi.org/10.7554/eLife.13722.001 PMID:26949251

  2. Histone demethylase JMJD2B is required for tumor cell proliferation and survival and is overexpressed in gastric cancer

    SciTech Connect

    Li, Wenjuan; Zhao, Li; Zang, Wen

    2011-12-16

    Highlights: Black-Right-Pointing-Pointer JMJD2B is required for cell proliferation and in vivo tumorigenesis. Black-Right-Pointing-Pointer JMJD2B depletion induces apoptosis and/or cell cycle arrest. Black-Right-Pointing-Pointer JMJD2B depletion activates DNA damage response and enhances p53 stabilization. Black-Right-Pointing-Pointer JMJD2B is overexpressed in human primary gastric cancer. -- Abstract: Epigenetic alterations such as aberrant expression of histone-modifying enzymes have been implicated in tumorigenesis. Jumonji domain containing 2B (JMJD2B) is a newly identified histone demethylase that regulates chromatin structure or gene expression by removing methyl residues from trimethylated lysine 9 on histone H3. Recent observations have shown oncogenic activity of JMJD2B. We explored the functional role ofmore » JMJD2B in cancer cell proliferation, survival and tumorigenesis, and determined its expression profile in gastric cancer. Knocking down JMJD2B expression by small interfering RNA (siRNA) in gastric and other cancer cells inhibited cell proliferation and/or induced apoptosis and elevated the expression of p53 and p21{sup CIP1} proteins. The enhanced p53 expression resulted from activation of the DNA damage response pathway. JMJD2B knockdown markedly suppressed xenograft tumor growth in vivo in mice. Moreover, JMJD2B expression was increased in primary gastric-cancer tissues of humans. Thus, JMJD2B is required for sustained proliferation and survival of tumor cells in vitro and in vivo, and its aberrant expression may contribute to the pathogenesis of gastric cancer.« less

  3. Boric acid inhibits human prostate cancer cell proliferation.

    PubMed

    Barranco, Wade T; Eckhert, Curtis D

    2004-12-08

    The role of boron in biology includes coordinated regulation of gene expression in mixed bacterial populations and the growth and proliferation of higher plants and lower animals. Here we report that boric acid, the dominant form of boron in plasma, inhibits the proliferation of prostate cancer cell lines, DU-145 and LNCaP, in a dose-dependent manner. Non-tumorigenic prostate cell lines, PWR-1E and RWPE-1, and the cancer line PC-3 were also inhibited, but required concentrations higher than observed human blood levels. Studies using DU-145 cells showed that boric acid induced a cell death-independent proliferative inhibition, with little effect on cell cycle stage distribution and mitochondrial function.

  4. 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

  5. Distinct T helper cell dependence of memory B-cell proliferation versus plasma cell differentiation.

    PubMed

    Zabel, Franziska; Fettelschoss, Antonia; Vogel, Monique; Johansen, Pål; Kündig, Thomas M; Bachmann, Martin F

    2017-03-01

    Several memory B-cell subclasses with distinct functions have been described, of which the most effective is the class-switched (CS) memory B-cell population. We have previously shown, using virus-like particles (VLPs), that the proliferative potential of these CS memory B cells is limited and they fail to re-enter germinal centres (GCs). However, VLP-specific memory B cells quickly differentiated into secondary plasma cells (PCs) with the virtue of elevated antibody production compared with primary PCs. Whereas the induction of VLP + memory B cells was strongly dependent on T helper cells, we were wondering whether re-stimulation of VLP + memory B cells and their differentiation into secondary PCs would also require T helper cells. Global absence of T helper cells led to strongly impaired memory B cell proliferation and PC differentiation. In contrast, lack of interleukin-21 receptor-dependent follicular T helper cells or CD40 ligand signalling strongly affected proliferation of memory B cells, but differentiation into mature secondary PCs exhibiting increased antibody production was essentially normal. This contrasts with primary B-cell responses, where a strong dependence on CD40 ligand but limited importance of interleukin-21 receptor was seen. Hence, T helper cell dependence differs between primary and secondary B-cell responses as well as between memory B-cell proliferation and PC differentiation. © 2016 John Wiley & Sons Ltd.

  6. Cardiomyocyte-released factors stimulate oligodendrocyte precursor cells proliferation

    SciTech Connect

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

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

  7. Targeting Aberrant Glutathione Metabolism to Eradicate Human Acute Myelogenous Leukemia Cells*

    PubMed Central

    Pei, Shanshan; Minhajuddin, Mohammad; Callahan, Kevin P.; Balys, Marlene; Ashton, John M.; Neering, Sarah J.; Lagadinou, Eleni D.; Corbett, Cheryl; Ye, Haobin; Liesveld, Jane L.; O'Dwyer, Kristen M.; Li, Zheng; Shi, Lei; Greninger, Patricia; Settleman, Jeffrey; Benes, Cyril; Hagen, Fred K.; Munger, Joshua; Crooks, Peter A.; Becker, Michael W.; Jordan, Craig T.

    2013-01-01

    The development of strategies to eradicate primary human acute myelogenous leukemia (AML) cells is a major challenge to the leukemia research field. In particular, primitive leukemia cells, often termed leukemia stem cells, are typically refractory to many forms of therapy. To investigate improved strategies for targeting of human AML cells we compared the molecular mechanisms regulating oxidative state in primitive (CD34+) leukemic versus normal specimens. Our data indicate that CD34+ AML cells have elevated expression of multiple glutathione pathway regulatory proteins, presumably as a mechanism to compensate for increased oxidative stress in leukemic cells. Consistent with this observation, CD34+ AML cells have lower levels of reduced glutathione and increased levels of oxidized glutathione compared with normal CD34+ cells. These findings led us to hypothesize that AML cells will be hypersensitive to inhibition of glutathione metabolism. To test this premise, we identified compounds such as parthenolide (PTL) or piperlongumine that induce almost complete glutathione depletion and severe cell death in CD34+ AML cells. Importantly, these compounds only induce limited and transient glutathione depletion as well as significantly less toxicity in normal CD34+ cells. We further determined that PTL perturbs glutathione homeostasis by a multifactorial mechanism, which includes inhibiting key glutathione metabolic enzymes (GCLC and GPX1), as well as direct depletion of glutathione. These findings demonstrate that primitive leukemia cells are uniquely sensitive to agents that target aberrant glutathione metabolism, an intrinsic property of primary human AML cells. PMID:24089526

  8. Understanding the Warburg effect: the metabolic requirements of cell proliferation.

    PubMed

    Vander Heiden, Matthew G; Cantley, Lewis C; Thompson, Craig B

    2009-05-22

    In contrast to normal differentiated cells, which rely primarily on mitochondrial oxidative phosphorylation to generate the energy needed for cellular processes, most cancer cells instead rely on aerobic glycolysis, a phenomenon termed "the Warburg effect." Aerobic glycolysis is an inefficient way to generate adenosine 5'-triphosphate (ATP), however, and the advantage it confers to cancer cells has been unclear. Here we propose that the metabolism of cancer cells, and indeed all proliferating cells, is adapted to facilitate the uptake and incorporation of nutrients into the biomass (e.g., nucleotides, amino acids, and lipids) needed to produce a new cell. Supporting this idea are recent studies showing that (i) several signaling pathways implicated in cell proliferation also regulate metabolic pathways that incorporate nutrients into biomass; and that (ii) certain cancer-associated mutations enable cancer cells to acquire and metabolize nutrients in a manner conducive to proliferation rather than efficient ATP production. A better understanding of the mechanistic links between cellular metabolism and growth control may ultimately lead to better treatments for human cancer.

  9. T cells which proliferate in response to concanavalin A include cells which proliferate in mixed leucocyte reactions.

    PubMed

    Watanabe, T; Fathman, C G; Coutinho, A

    1977-09-01

    Selection in long-term culture of alloreactive T cells, by successive in vitro restimulation with semi-allogeneic cells, results in primed responder cell populations which maintain full proliferative reactivity to allogeneic cells as well as to the T cell mitogens concanavalin A (Con A) and phytohemagglutinin (PHA) but are depleted of cells which can effect target cell destruction in either a specific or nonspecific manner. Con A-induced T cell blasts (selected by velocity sedimentation) can revert to small resting lymphocytes in the presence of inert "filler" cells. Con A blasts which have reverted, readily proliferate in response to Con A or allogeneic stimulator cells but are largely depleted of effector killer cells and PHA-responsive cells.

  10. Downregulated circular RNA hsa_circ_0001649 regulates proliferation, migration and invasion in cholangiocarcinoma cells.

    PubMed

    Xu, Yi; Yao, Yue; Zhong, Xiangyu; Leng, Kaiming; Qin, Wei; Qu, Lijun; Cui, Yunfu; Jiang, Xingming

    2018-02-05

    Cholangiocarcinoma (CCA) is one of the most aggressive malignancies with increasing worldwide incidence and is characterized by unfavorable prognosis due to its early invasive characteristics and poor response to chemotherapy or radiotherapy. Accumulating evidence has indicated that aberrantly expressed circular RNAs (circRNAs) are involved in cancer development and progression. However, their clinical values and biological roles in CCA remain unclear. Hsa_circ_0001649, a novel cancer-related circRNA, has been previously reported to be downregulated in hepatocellular carcinoma and gastric cancer. In the present study, qRT-PCR was carried out to measure the expression of hsa_circ_0001649 in CCA tissue samples and cell lines, and the correlation between hsa_circ_0001649 expression and clinicopathologic features was analyzed. The biological functions of hsa_circ_0001649 in CCA cells were evaluated both in vitro and in vivo. As a result, hsa_circ_0001649 was aberrantly downregulated in CCA tissues and cells, and this downregulation was associated with tumor size and differentiation grade in CCA. In addition, hsa_circ_0001649 overexpression caused tumor suppressive effects via inhibiting cell proliferation, migration and invasion; inducing cell apoptosis in KMBC and Huh-28 cells. On the contrary, silencing of hsa_circ_0001649 caused the opposite phenotypes. Furthermore, tumor xenograft study confirmed the in vitro results. Collectively, our findings suggest that hsa_circ_0001649 might be a rational CCA-related therapeutic target. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. 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.

  12. 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.

  13. Poisson-event-based analysis of cell proliferation.

    PubMed

    Summers, Huw D; Wills, John W; Brown, M Rowan; Rees, Paul

    2015-05-01

    A protocol for the assessment of cell proliferation dynamics is presented. This is based on the measurement of cell division events and their subsequent analysis using Poisson probability statistics. Detailed analysis of proliferation dynamics in heterogeneous populations requires single cell resolution within a time series analysis and so is technically demanding to implement. Here, we show that by focusing on the events during which cells undergo division rather than directly on the cells themselves a simplified image acquisition and analysis protocol can be followed, which maintains single cell resolution and reports on the key metrics of cell proliferation. The technique is demonstrated using a microscope with 1.3 μm spatial resolution to track mitotic events within A549 and BEAS-2B cell lines, over a period of up to 48 h. Automated image processing of the bright field images using standard algorithms within the ImageJ software toolkit yielded 87% accurate recording of the manually identified, temporal, and spatial positions of the mitotic event series. Analysis of the statistics of the interevent times (i.e., times between observed mitoses in a field of view) showed that cell division conformed to a nonhomogeneous Poisson process in which the rate of occurrence of mitotic events, λ exponentially increased over time and provided values of the mean inter mitotic time of 21.1 ± 1.2 hours for the A549 cells and 25.0 ± 1.1 h for the BEAS-2B cells. Comparison of the mitotic event series for the BEAS-2B cell line to that predicted by random Poisson statistics indicated that temporal synchronisation of the cell division process was occurring within 70% of the population and that this could be increased to 85% through serum starvation of the cell culture. © 2015 International Society for Advancement of Cytometry.

  14. Effect of different wound dressings on cell viability and proliferation.

    PubMed

    Paddle-Ledinek, Joanne E; Nasa, Zeyad; Cleland, Heather J

    2006-06-01

    Many new dressings have been developed since the early 1980s. Wound healing comprises cleansing, granulation/vascularization, and epithelialization phases. An optimum microenvironment and the absence of cytotoxic factors are essential for epithelialization. This study examines the effect of extracts of different wound dressings on keratinocyte survival and proliferation. Keratinocyte cultures were exposed for 40 hours to at least three extracts of each of the following wound dressings, which were tested in octuplicate: Acticoat, Aquacel-Ag, Aquacel, Algisite M, Avance, Comfeel Plus transparent, Contreet-H, Hydrasorb, and SeaSorb. Silicone extract provided the reference material. Controls were included of cells cultured in medium that had been incubated under conditions identical to those used with the extracts. Cell survival (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide reduction) and proliferation (5-bromo-2':-deoxyuridine incorporation) were measured. Extracts of silver-containing dressings (Acticoat, Aquacel-Ag, Contreet-H, and Avance) were most cytotoxic. Extracts of Hydrasorb were less cytotoxic but markedly affected keratinocyte proliferation and morphology. Extracts of alginate-containing dressings (Algisite M, SeaSorb, and Contreet-H) demonstrated high calcium concentrations, markedly reduced keratinocyte proliferation, and affected keratinocyte morphology. Extracts of Aquacel and Comfeel Plus transparent induced small but significant inhibition of keratinocyte proliferation. The principle of minimizing harm should be applied to the choice of wound dressing. Silver-based dressings are cytotoxic and should not be used in the absence of infection. Alginate dressings with high calcium content affect keratinocyte proliferation probably by triggering terminal differentiation of keratinocytes. Such dressings should be used with caution in cases in which keratinocyte proliferation is essential. All dressings should be tested in vitro before

  15. Estimation of Cell Proliferation Dynamics Using CFSE Data

    PubMed Central

    Banks, H.T.; Sutton, Karyn L.; Thompson, W. Clayton; Bocharov, Gennady; Roose, Dirk; Schenkel, Tim; Meyerhans, Andreas

    2010-01-01

    Advances in fluorescent labeling of cells as measured by flow cytometry have allowed for quantitative studies of proliferating populations of cells. The investigations (Luzyanina et al. in J. Math. Biol. 54:57–89, 2007; J. Math. Biol., 2009; Theor. Biol. Med. Model. 4:1–26, 2007) contain a mathematical model with fluorescence intensity as a structure variable to describe the evolution in time of proliferating cells labeled by carboxyfluorescein succinimidyl ester (CFSE). Here, this model and several extensions/modifications are discussed. Suggestions for improvements are presented and analyzed with respect to statistical significance for better agreement between model solutions and experimental data. These investigations suggest that the new decay/label loss and time dependent effective proliferation and death rates do indeed provide improved fits of the model to data. Statistical models for the observed variability/noise in the data are discussed with implications for uncertainty quantification. The resulting new cell dynamics model should prove useful in proliferation assay tracking and modeling, with numerous applications in the biomedical sciences. PMID:20195910

  16. Proliferate and survive: cell division cycle and apoptosis in human neuroblastoma.

    PubMed

    Borriello, Adriana; Roberto, Roberta; Della Ragione, Fulvio; Iolascon, Achille

    2002-02-01

    Neuroblastoma is one of the most frequent childhood cancers and a major cause of death from neoplasias of infancy. Although a wealth of studies on its molecular bases have been carried out, little conclusive information about its origin and evolution is available. Some intriguing findings have correlated neuroblastoma development with aberrations of two pivotal cellular processes generally altered in human cancers, namely cell division cycle and apoptosis. Indeed, it has been reported that neuroblastoma cell lines show accumulation of Id2 protein, a factor which is able to hamper the pRb protein antiproliferative activity. The increased Id2 is due to N-myc gene amplification and overexpression, a phenomenon frequently observed in neuroblastoma and an important independent negative marker. Moreover, neuroblastoma cells are frequently characterized by increased levels of survivin, an inhibitor of the apoptotic response, and by a deficiency of procaspase 8, a key intermediate of the programmed cell death cascade. These two events, probably, make neuroblastomas more resistant to programmed cell death. These recent findings might suggest that neuroblastoma cells have acquired the capability to proliferate easily and die difficultly. The mechanistic meaning of these data will be discussed in the present review. Moreover, we will suggest new therapeutic scenarios opened up by the described alterations of cell cycle and apoptosis engines.

  17. Inhibition of cyclooxygenase (COX)-2 affects endothelial progenitor cell proliferation

    SciTech Connect

    Colleselli, Daniela; Bijuklic, Klaudija; Mosheimer, Birgit A.

    2006-09-10

    Growing evidence indicates that inducible cyclooxygenase-2 (COX-2) is involved in the pathogenesis of inflammatory disorders and various types of cancer. Endothelial progenitor cells recruited from the bone marrow have been shown to be involved in the formation of new vessels in malignancies and discussed for being a key point in tumour progression and metastasis. However, until now, nothing is known about an interaction between COX and endothelial progenitor cells (EPC). Expression of COX-1 and COX-2 was detected by semiquantitative RT-PCR and Western blot. Proliferation kinetics, cell cycle distribution and rate of apoptosis were analysed by MTT test and FACS analysis.more » Further analyses revealed an implication of Akt phosphorylation and caspase-3 activation. Both COX-1 and COX-2 expression can be found in bone-marrow-derived endothelial progenitor cells in vitro. COX-2 inhibition leads to a significant reduction in proliferation of endothelial progenitor cells by an increase in apoptosis and cell cycle arrest. COX-2 inhibition leads further to an increased cleavage of caspase-3 protein and inversely to inhibition of Akt activation. Highly proliferating endothelial progenitor cells can be targeted by selective COX-2 inhibition in vitro. These results indicate that upcoming therapy strategies in cancer patients targeting COX-2 may be effective in inhibiting tumour vasculogenesis as well as angiogenic processes.« less

  18. Long Noncoding RNA PANDA Positively Regulates Proliferation of Osteosarcoma Cells.

    PubMed

    Kotake, Yojiro; Goto, Taiki; Naemura, Madoka; Inoue, Yasutoshi; Okamoto, Haruna; Tahara, Keiichiro

    2017-01-01

    A long noncoding RNA, p21-associated ncRNA DNA damage-activated (PANDA), associates with nuclear transcription factor Y subunit alpha (NF-YA) and inhibits its binding to promoters of apoptosis-related genes, thereby repressing apoptosis in normal human fibroblasts. Here, we show that PANDA is involved in regulating proliferation in the U2OS human osteosarcoma cell line. U2OS cells were transfected with siRNAs against PANDA 72 h later and they were subjected to reverse transcription-polymerase chain reaction (RT-PCR), quantitative RT-PCR and cell-cycle analysis. PANDA was highly expressed in U2OS cells, and its expression was induced by DNA damage. Silencing PANDA caused arrest at the G 1 phase of the cell cycle, leading to inhibition of cell proliferation. Quantitative RT-PCR showed that silencing PANDA increased mRNA levels of the cyclin-dependent kinase inhibitor p18, which caused G 1 phase arrest. These results suggest that PANDA promotes G 1 -S transition by repressing p18 transcription, and thus promotes U2OS cell proliferation. Copyright© 2017 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  19. Chromosomal aberrations and delays in cell progression induced by x-rays in Tradescantia clone 02 meristems

    SciTech Connect

    Geard, C.R.

    1983-01-01

    In root meristems of Tradescantia clone 02 (developed by Sparrow and his colleagues for mutation studies), X-rays interfere with the progression of cells through the cell cycle and induce chromosomal aberrations in a dose-dependent manner consistent with linear-quadratic kinetics. Sequential mitotic cell accumulations after irradiation indicate that sensitivity to aberration induction is probably greatest in cells from late S to early G2, with chromatid interchanges the most frequent aberration type and all aberrations consistent with initiation from the interaction between two lesions. The ratio of the coefficients in the linear (..cap alpha..) and the quadratic (..beta..) terms (..cap alpha../..beta..) ismore » equal to the dose average of specific energy produced by individual particles in the site where interaction takes place. The ratio ..cap alpha../..beta.. for chromosomal aberrations is similar to that previously found for X-ray-induced mutation in Tradescantia stamen hairs, supporting the proposal that radiation-induced mutational events are due to chromosomal aberrations with interaction distances of about 1..mu..m. Abrahamson and co-workers have noted that both ..cap alpha../..beta.. ratios appear to be related to nuclear target size and are similar for chromosomal and mutational endpoints in the same organism. These findings support this concept; however, it is apparent that any situation which diminishes yield at high doses (e.g., mitotic delay) will probably affect the ..beta.. component. 23 references, 5 figures, 2 tables.« less

  20. Trivial role for NSMCE2 during in vitro proliferation and differentiation of male germline stem cells.

    PubMed

    Zheng, Yi; Jongejan, Aldo; Mulder, Callista L; Mastenbroek, Sebastiaan; Repping, Sjoerd; Wang, Yinghua; Li, Jinsong; Hamer, Geert

    2017-09-01

    Spermatogenesis, starting with spermatogonial differentiation, is characterized by ongoing and dramatic alterations in composition and function of chromatin. Failure to maintain proper chromatin dynamics during spermatogenesis may lead to mutations, chromosomal aberrations or aneuploidies. When transmitted to the offspring, these can cause infertility or congenital malformations. The structural maintenance of chromosomes (SMC) 5/6 protein complex has recently been described to function in chromatin modeling and genomic integrity maintenance during spermatogonial differentiation and meiosis. Among the subunits of the SMC5/6 complex, non-SMC element 2 (NSMCE2) is an important small ubiquitin-related modifier (SUMO) ligase. NSMCE2 has been reported to be essential for mouse development, prevention of cancer and aging in adult mice and topological stress relief in human somatic cells. By using in vitro cultured primary mouse spermatogonial stem cells (SSCs), referred to as male germline stem (GS) cells, we investigated the function of NSMCE2 during spermatogonial proliferation and differentiation. We first optimized a protocol to generate genetically modified GS cell lines using CRISPR-Cas9 and generated an Nsmce2 -/- GS cell line. Using this Nsmce2 -/- GS cell line, we found that NSMCE2 was dispensable for proliferation, differentiation and topological stress relief in mouse GS cells. Moreover, RNA sequencing analysis demonstrated that the transcriptome was only minimally affected by the absence of NSMCE2. Only differential expression of Sgsm1 appeared highly significant, but with SGSM1 protein levels being unaffected without NSMCE2. Hence, despite the essential roles of NSMCE2 in somatic cells, chromatin integrity maintenance seems differentially regulated in the germline. © 2017 Society for Reproduction and Fertility.

  1. mTORβ Splicing Isoform Promotes Cell Proliferation and Tumorigenesis*

    PubMed Central

    Panasyuk, Ganna; Nemazanyy, Ivan; Zhyvoloup, Aleksander; Filonenko, Valeriy; Davies, Derek; Robson, Mathew; Pedley, R. Barbara; Waterfield, Michael; Gout, Ivan

    2009-01-01

    The mTOR (mammalian target of rapamycin) promotes growth in response to nutrients and growth factors and is deregulated in numerous pathologies, including cancer. The mechanisms by which mTOR senses and regulates energy metabolism and cell growth are relatively well understood, whereas the molecular events underlining how it mediates survival and proliferation remain to be elucidated. Here, we describe the existence of the mTOR splicing isoform, TORβ, which, in contrast to the full-length protein (mTORα), has the potential to regulate the G1 phase of the cell cycle and to stimulate cell proliferation. mTORβ is an active protein kinase that mediates downstream signaling through complexing with Rictor and Raptor proteins. Remarkably, overexpression of mTORβ transforms immortal cells and is tumorigenic in nude mice and therefore could be a proto-oncogene. PMID:19726679

  2. Evidence for a role of Collapsin response mediator protein-2 in signaling pathways that regulate the proliferation of non-neuronal cells

    SciTech Connect

    Tahimic, Candice Ginn T.; Tomimatsu, Nozomi; Nishigaki, Ryuichi

    Collapsin response mediator protein-2 or Crmp-2 plays a critical role in the establishment of neuronal polarity. In this study, we present evidence that apart from its functions in neurodevelopment, Crmp-2 is also involved in pathways that regulate the proliferation of non-neuronal cells through its phosphorylation by regulatory proteins. We show that Crmp-2 undergoes dynamic phosphorylation changes in response to contact inhibition-induced quiescence and that hyperphosphorylation of Crmp-2 occurs in a tumor. We further suggest that de-regulation of Crmp-2 phosphorylation levels at certain amino acid residues may lead to aberrant cell proliferation and consequently, tumorigenesis.

  3. Immortalized myogenic cells from congenital muscular dystrophy type1A patients recapitulate aberrant caspase activation in pathogenesis: a new tool for MDC1A research

    PubMed Central

    2013-01-01

    Background Congenital muscular dystrophy Type 1A (MDC1A) is a severe, recessive disease of childhood onset that is caused by mutations in the LAMA2 gene encoding laminin-α2. Studies with both mouse models and primary cultures of human MDC1A myogenic cells suggest that aberrant activation of cell death is a significant contributor to pathogenesis in laminin-α2-deficiency. Methods To overcome the limited population doublings of primary cultures, we generated immortalized, clonal lines of human MDC1A myogenic cells via overexpression of both CDK4 and the telomerase catalytic component (human telomerase reverse transcriptase (hTERT)). Results The immortalized MDC1A myogenic cells proliferated indefinitely when cultured at low density in high serum growth medium, but retained the capacity to form multinucleate myotubes and express muscle-specific proteins when switched to low serum medium. When cultured in the absence of laminin, myotubes formed from immortalized MDC1A myoblasts, but not those formed from immortalized healthy or disease control human myoblasts, showed significantly increased activation of caspase-3. This pattern of aberrant caspase-3 activation in the immortalized cultures was similar to that found previously in primary MDC1A cultures and laminin-α2-deficient mice. Conclusions Immortalized MDC1A myogenic cells provide a new resource for studies of pathogenetic mechanisms and for screening possible therapeutic approaches in laminin-α2-deficiency. PMID:24314268

  4. Immortalized myogenic cells from congenital muscular dystrophy type1A patients recapitulate aberrant caspase activation in pathogenesis: a new tool for MDC1A research.

    PubMed

    Yoon, Soonsang; Stadler, Guido; Beermann, Mary Lou; Schmidt, Eric V; Windelborn, James A; Schneiderat, Peter; Wright, Woodring E; Miller, Jeffrey Boone

    2013-12-06

    Congenital muscular dystrophy Type 1A (MDC1A) is a severe, recessive disease of childhood onset that is caused by mutations in the LAMA2 gene encoding laminin-α2. Studies with both mouse models and primary cultures of human MDC1A myogenic cells suggest that aberrant activation of cell death is a significant contributor to pathogenesis in laminin-α2-deficiency. To overcome the limited population doublings of primary cultures, we generated immortalized, clonal lines of human MDC1A myogenic cells via overexpression of both CDK4 and the telomerase catalytic component (human telomerase reverse transcriptase (hTERT)). The immortalized MDC1A myogenic cells proliferated indefinitely when cultured at low density in high serum growth medium, but retained the capacity to form multinucleate myotubes and express muscle-specific proteins when switched to low serum medium. When cultured in the absence of laminin, myotubes formed from immortalized MDC1A myoblasts, but not those formed from immortalized healthy or disease control human myoblasts, showed significantly increased activation of caspase-3. This pattern of aberrant caspase-3 activation in the immortalized cultures was similar to that found previously in primary MDC1A cultures and laminin-α2-deficient mice. Immortalized MDC1A myogenic cells provide a new resource for studies of pathogenetic mechanisms and for screening possible therapeutic approaches in laminin-α2-deficiency.

  5. Analysis of Heavy Ion-Induced Chromosome Aberrations in Human Fibroblast Cells Using In Situ Hybridization

    NASA Technical Reports Server (NTRS)

    Wu, Honglu; Durante, Marco; Furusawa, Yoshiya; George, Kerry; Kawata, Tetsuya; Cucinotta, Francis A.

    2003-01-01

    Confluent human fibroblast cells (AG1522) were irradiated with gamma rays, 490 MeV/nucleon Si, or with Fe ions at either 200 or 500 MeV/nucleon. The cells were allowed to repair at 37 0 C for 24 hours after exposure, and a chemically induced premature chromosome condensation (PCC) technique was used to condense chromosomes in the G2 phase of the cell cycle. Unrejoined chromosomal breaks and complex exchanges were analyzed in the irradiated samples. In order to verify that chromosomal breaks were truly unrejoined, chromosome aberrations were analyzed using a combination of whole chromosome specific probes and probes specific for the telomere region of the chromosome. Results showed that the frequency of unrejoined chromosome breaks was higher after high-LET radiation, and consequently, the ratio of incomplete to complete exchanges increased steadily with LET up to 440 keV/micron, the highest LET value in the present study. For samples exposed to 200 MeV/nucleon Fe ions, chromosome aberrations were analyzed using the multicolor FISH (mFISH) technique that allows identification of both complex and truly incomplete exchanges. Results of the mFISH study showed that 0.7 and 3 Gy dose of the Fe ions produced similar ratios of complex to simple exchanges and incomplete to complete exchanges, values for which were higher than those obtained after a 6 Gy gamma exposure. After 0.7 Gy of Fe ions, most complex aberrations were found to involve three or four chromosomes, indicating the maximum number of chromosome domains traversed by a single Fe ion track. 2

  6. NOTCH1 Is Aberrantly Activated in Chronic Lymphocytic Leukemia Hematopoietic Stem Cells.

    PubMed

    Di Ianni, Mauro; Baldoni, Stefano; Del Papa, Beatrice; Aureli, Patrizia; Dorillo, Erica; De Falco, Filomena; Albi, Elisa; Varasano, Emanuela; Di Tommaso, Ambra; Giancola, Raffaella; Accorsi, Patrizia; Rotta, Gianluca; Rompietti, Chiara; Silva Barcelos, Estevão Carlos; Campese, Antonio Francesco; Di Bartolomeo, Paolo; Screpanti, Isabella; Rosati, Emanuela; Falzetti, Franca; Sportoletti, Paolo

    2018-01-01

    To investigate chronic lymphocytic leukemia (CLL)-initiating cells, we assessed NOTCH1 mutation/expression in hematopoietic stem cells (HSCs). In NOTCH1- mutated CLL, we detected subclonal mutations in 57% CD34+/CD38- HSCs. NOTCH1 mutation was present in 66% CD34+/CD38+ progenitor cells displaying an increased mutational burden compared to HSCs. Flow cytometric analysis revealed significantly higher NOTCH1 activation in CD34+/CD38- and CD34+/CD38+ cells from CLL patients, regardless NOTCH1 mutation compared to healthy donors. Activated NOTCH1 resulted in overexpression of the NOTCH1 target c-MYC. We conclude that activated NOTCH1 is an early event in CLL that may contribute to aberrant HSCs in this disease.

  7. Heparan sulfate niche for cell proliferation in the adult brain.

    PubMed

    Mercier, Frederic; Arikawa-Hirasawa, Eri

    2012-02-29

    In adulthood, new neurons and glial cells are generated from stem cells in restricted zones of the brain, namely the olfactory bulb (OB), rostral migratory stream (RMS), subventricular zone (SVZ) of the lateral ventricle, sub-callosum zone (SCZ) and sub-granular layer (SGL) of the dentate gyrus. What makes these zones germinal? We previously reported that N-sulfated heparan sulfates (N-sulfated HS) present in specialized extracellular matrix structures (fractones) and vascular basement membranes bind the neurogenic factor FGF-2 (fibroblast growth factor-2) next to stem cells in the anterior SVZ of the lateral ventricle, the most neurogenic zone in adulthood. To determine to which extent cell proliferation is associated with N-sulfated HS, we mapped N-sulfated HS and proliferating cells by immunohistochemistry throughout the adult mouse brain. We found that cell proliferation is associated with N-sulfated HS in the OB, RMS, the whole germinal SVZ, and the SCZ. Cell proliferation was weakly associated with N-sulfated HS in the SGL, but the SGL was directly connected to a sub-cortical N-sulfated HS+ extension of the meninges. The NS-sulfated HS+ structures were blood vessels in the OB, RMS and SCZ, and primarily fractones in the SVZ. N-sulfated HS+ fractones, blood vessels and meninges formed a continuum that coursed along the OB, SVZ, RMS, SCZ and SGL, challenging the view that these structures are independent germinal entities. These results support the possibility that a single anatomical system might be globally responsible for mitogenesis and ultimately the production of new neurons and glial cells in the adult brain. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  8. 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

  9. A Neural Network Based Workstation for Automated Cell Proliferation Analysis

    DTIC Science & Technology

    2001-10-25

    work was supported by the Programa de Apoyo a Proyectos de Desarrollo e Investigacíon en Informática REDII 2000. We thank Blanca Itzel Taboada for...Meléndez1, G. Corkidi.2 1Centro de Instrumentos, UNAM. P.O. Box 70-186, México 04510, D.F. 2Instituto de Biotecnología, UNAM. P.O. Box 510-3, 62250...proliferation analysis, of cytological microscope images. The software of the system assists the expert biotechnologist during cell proliferation and

  10. Promotion of stem cell proliferation by vegetable peptone.

    PubMed

    Lee, J; Lee, J; Hwang, H; Jung, E; Huh, S; Hyun, J; Park, D

    2009-10-01

    Technical limitations and evolution of therapeutic applications for cell culture-derived products have accelerated elimination of animal-derived constituents from such products to minimize inadvertent introduction of microbial contaminants, such as fungi, bacteria or viruses. The study described here was conducted to investigate the proliferative effect of vegetable peptone on adult stem cells in the absence of serum, and its possible mechanisms of action. Cell viability and proliferation were determined using the MTT assay and Click-iT EdU flow cytometry, respectively. In addition, changes in expression of cytokine genes were analysed using MILLIPLEX human cytokine enzyme-linked immunosorbent assay kit. Viability of cord blood-derived mesenchymal stem cells (CB-MSC) and adipose tissue-derived stem cells (ADSC) increased significantly when treated with the peptone. In addition, median value of the group treated with peptone shifted to the right when compared to the untreated control group. Furthermore, quantitative analysis of the cytokines revealed that production of vascular endothelial growth factor (VEGF), transforming growth factor-beta1 (TGF-beta1), and interleukin-6 (IL-6) increased significantly in response to treatment with our vegetable peptone in both CB-MSCs and ADSCs. Our findings revealed that the vegetable peptone promotes proliferation of CB-MSCs and ADSCs. In addition, results of this study suggest that induction of stem cell proliferation by vegetable peptone is likely to be related to its induction of VEGF, TGF-beta1, and IL-6 expression.

  11. P53 protein in proliferation, repair and apoptosis of cells.

    PubMed

    Wawryk-Gawda, Ewelina; Chylińska-Wrzos, Patrycja; Lis-Sochocka, Marta; Chłapek, Katarzyna; Bulak, Kamila; Jędrych, Marian; Jodłowska-Jędrych, Barbara

    2014-05-01

    The p53 protein is an important factor of many intra- and extracellular processes. This protein regulates the repair of cellular DNA and induces apoptosis. It is also responsible for the regulation of the senescence and the cell entering the subsequent stages of the cellular cycle. The protein p53 is also involved in inhibiting angiogenesis and the induction of oxidative shock. In our study, we examined the activity of p53 protein in the uterine epithelial cells in rats treated with cladribine. Its action is mainly based on apoptosis induction. We compared the activity of p53 protein in cells with a high apoptosis index and in cells with active repair mechanisms and high proliferation index. We observed stronger p53 protein expression in the epithelial cells of the materials taken 24 h after the last dose of 2-CdA associated with the active process of apoptosis and inhibition of proliferation. After 4 weeks from the last dose of cladribine, the stronger expression of p53 protein was associated with both the existing changes in the cell's genome, the effects of the ongoing repair mechanisms, as well as the high proliferation activity.

  12. Chromosome Aberrations in Cells Infected with Bovine Papillomavirus: Comparing Cutaneous Papilloma, Esophagus Papilloma, and Urinary Bladder Lesion Cells

    PubMed Central

    Campos, S. R. C.; Melo, T. C.; Assaf, S.; Araldi, R. P.; Mazzuchelli-de-Souza, J.; Sircili, M. P.; Carvalho, R. F.; Roperto, F.; Beçak, W.; Stocco, R. C.

    2013-01-01

    The majority of malignant cells present genetic instability with chromosome number changes plus segmental defects: these changes involve intact chromosomes and breakage-induced alterations. Some pathways of chromosomal instability have been proposed as random breakage, telomere fusion, and centromere fission. Chromosome alterations in tumor cells have been described in animal models and in vitro experiments. One important question is about possible discrepancies between animal models, in vitro studies, and the real events in cancer cells in vivo. Papillomaviruses are relevant agents in oncogenic processes related to action on host genome. Recently, many reports have discussed the presence of virus DNA in peripheral blood, in humans and in animals infected by papillomaviruses. The meaning of this event is of controversy: possible product of apoptosis occurring in cancer cells, metastasized cancer cells, or active DNA sequences circulating in bloodstream. This study compares chromosome aberrations detected in bovine cells, in peripheral blood cells, and in BPV lesion cells: the literature is poor in this type of study. Comparing chromosome aberrations described in the different cells, a common mechanism in their origin, can be suggested. Furthermore blood cells can be evaluated as an effective way of virus transmission. PMID:24298391

  13. Proton and Fe Ion-Induced Early and Late Chromosome Aberrations in Different Cell Types

    NASA Technical Reports Server (NTRS)

    Wu, Honglu; Lu, Tao; Yeshitla, Samrawit; Zhang, Ye; Kadhim, Munira

    2016-01-01

    An early stage of cancer development is believed to be genomic instability (GI) which accelerates the mutation rate in the descendants of the cells surviving radiation exposure. To investigate GI induced by charged particles, we exposed human lymphocytes, human fibroblast cells, and human mammary epithelial cells to high energy protons and Fe ions. In addition, we also investigated GI in bone marrow cells isolated from CBA/CaH (CBA) and C57BL/6 (C57) mice, by analyzing cell survival and chromosome aberrations in the cells after multiple cell divisions. Results analyzed so far from the experiments indicated different sensitivities to charged particles between CBA/CaH (CBA) and C57BL/6 (C57) mouse strains, suggesting that there are two main types of response to irradiation: 1) responses associated with survival of damaged cells and 2) responses associated with the induction of non-clonal chromosomal instability in the surviving progeny of stem cells. Previously, we reported that the RBE for initial chromosome damages was high in human lymphocytes exposed to Fe ions. Our results with different cell types demonstrated different RBE values between different cell types and between early and late chromosomal damages. This study also attempts to offer an explanation for the varying RBE values for different cancer types.

  14. Effects of sulforaphane on neural stem cell proliferation and differentiation.

    PubMed

    Han, Zhenxian; Xu, Qian; Li, Changfu; Zhao, Hong

    2017-03-01

    Sulforaphane (SFN) is a natural organosulfur compound with anti-oxidant and anti-inflammation properties. The objective of this study is to investigate the effect of SFN on the proliferation and differentiation of neural stem cells (NSC). NSCs were exposed to SFN at the concentrations ranging from 0.25 to 10 µM. Cell viability was evaluated with MTT assay and lactate dehydogenase (LDH) release assay. The proliferation of NSCs was evaluated with neurosphere formation assay and Ki-67 staining. The level of Tuj-1 was evaluated with immunostaining and Western blot to assess NSC neuronal differentiation. The expression of key proteins in the Wnt signaling pathway, including β-catenin and cyclin D1, in response to SFN treatment or the Wnt inhibitor, DKK-1, was determined by Western blotting. No significant cytotoxicity was seen for SFN on NSCs with SFN at concentrations of less than 10 µM. On the contrary, SFN of low concentrations stimulated cell proliferation and prominently increased neurosphere formation and NSC differentiation to neurons. SFN treatment upregulated Wnt signaling in the NSCs, whereas DKK-1 attenuated the effects of SFN. SFN is a drug to promote NSC proliferation and neuronal differentiation when used at low concentrations. These protective effects are mediated by Wnt signaling pathway. © 2017 Wiley Periodicals, Inc.

  15. Protein Kinase Cα Modulates Estrogen-Receptor-Dependent Transcription and Proliferation in Endometrial Cancer Cells

    PubMed Central

    Thorne, Alicia M.; Jackson, Twila A.; Willis, Van C.; Bradford, Andrew P.

    2013-01-01

    Endometrial cancer is the most common invasive gynecologic malignancy in developed countries. The most prevalent endometrioid tumors are linked to excessive estrogen exposure and hyperplasia. However, molecular mechanisms and signaling pathways underlying their etiology and pathophysiology remain poorly understood. We have shown that protein kinase Cα (PKCα) is aberrantly expressed in endometrioid tumors and is an important mediator of endometrial cancer cell survival, proliferation, and invasion. In this study, we demonstrate that expression of active, myristoylated PKCα conferred ligand-independent activation of estrogen-receptor- (ER-) dependent promoters and enhanced responses to estrogen. Conversely, knockdown of PKCα reduced ER-dependent gene expression and inhibited estrogen-induced proliferation of endometrial cancer cells. The ability of PKCα to potentiate estrogen activation of ER-dependent transcription was attenuated by inhibitors of phosphoinositide 3-kinase (PI3K) and Akt. Evidence suggests that PKCα and estrogen signal transduction pathways functionally interact, to modulate ER-dependent growth and transcription. Thus, PKCα signaling, via PI3K/Akt, may be a critical element of the hyperestrogenic environment and activation of ER that is thought to underlie the development of estrogen-dependent endometrial hyperplasia and malignancy. PKCα-dependent pathways may provide much needed prognostic markers of aggressive disease and novel therapeutic targets in ER positive tumors. PMID:23843797

  16. Oncogenic Kit signals on endolysosomes and endoplasmic reticulum are essential for neoplastic mast cell proliferation

    PubMed Central

    Obata, Yuuki; Toyoshima, Shota; Wakamatsu, Ei; Suzuki, Shunichi; Ogawa, Shuhei; Esumi, Hiroyasu; Abe, Ryo

    2014-01-01

    Kit is a receptor-type tyrosine kinase found on the plasma membrane. It can transform mast cells through activating mutations. Here, we show that a mutant Kit from neoplastic mast cells from mice, Kit(D814Y), is permanently active and allows cells to proliferate autonomously. It does so by activating two signalling pathways from different intracellular compartments. Mutant Kit from the cell surface accumulates on endolysosomes through clathrin-mediated endocytosis, which requires Kit’s kinase activity. Kit(D814Y) is constitutively associated with phosphatidylinositol 3-kinase, but the complex activates Akt only on the cytoplasmic surface of endolysosomes. It resists destruction because it is under-ubiquitinated. Kit(D814Y) also appears in the endoplasmic reticulum soon after biosynthesis, and there, can activate STAT5 aberrantly. These mechanisms of oncogenic signalling are also seen in rat and human mast cell leukemia cells. Thus, oncogenic Kit signalling occurs from different intracellular compartments, and the mutation acts by altering Kit trafficking as well as activation. PMID:25493654

  17. The Retinoblastoma pathway regulates stem cell proliferation in freshwater planarians.

    PubMed

    Zhu, Shu Jun; Pearson, Bret J

    2013-01-15

    Freshwater planarians are flatworms of the Lophotrochozoan superphylum and are well known for their regenerative abilities, which rely on a large population of pluripotent adult stem cells. However, the mechanisms by which planarians maintain a precise population of adult stem cells while balancing proliferation and cell death, remain to be elucidated. Here we have identified, characterized, and functionally tested the core Retinoblastoma (Rb) pathway components in planarian adult stem cell biology. The Rb pathway is an ancient and conserved mechanism of proliferation control from plants to animals and is composed of three core components: an Rb protein, and a transcription factor heterodimer of E2F and DP proteins. Although the planarian genome contains all components of the Rb pathway, we found that they have undergone gene loss from the ancestral state, similar to other species in their phylum. The single Rb homolog (Smed-Rb) was highly expressed in planarian stem cells and was required for stem cell maintenance, similar to the Rb-homologs p107 and p130 in vertebrates. We show that planarians and their phylum have undergone the most severe reduction in E2F genes observed thus far, and the single remaining E2F was predicted to be a repressive-type E2F (Smed-E2F4-1). Knockdown of either Smed-E2F4-1 or its dimerization partner Dp (Smed-Dp) by RNAi resulted in temporary hyper-proliferation. Finally, we showed that known Rb-interacting genes in other systems, histone deacetylase 1 and cyclinD (Smed-HDAC1; Smed-cycD), were similar to Rb in expression and phenotypes when knocked down by RNAi, suggesting that these established interactions with Rb may also be conserved in planarians. Together, these results showed that planarians use the conserved components of the Rb tumor suppressor pathway to control proliferation and cell survival. Copyright © 2012 Elsevier Inc. All rights reserved.

  18. [Regulation of airway stem cell proliferation in idiopathic pulmonary fibrosis].

    PubMed

    Yang, S X; Wu, Q; Sun, X; Li, X; Li, K; Xu, L; Li, Y; Zhang, Q Y; Zhang, Y C; Chen, H Y

    2016-09-01

    To investigate the effect of fibroblasts on regulating airway stem cell proliferation in idiopathic pulmonary fibrosis. Lung cell suspension was prepared from β-actin-GFP mice. Airway stem cells were obtained by fluorescence activated cell sorting and co-cultured with lung fibroblasts. The fibroblasts were treated with TGF-β inhibitor SB43142. The expression of growth factors FGF1/2 and the effect of FGF1/2 on stem cell proliferation were observed. The cloning efficiency of airway stem cells, when co-cultured with normal lung fibroblast cells for 8 days, was (3.5±1.1)%, while the cloning efficiency was reduced to (0.04±0.04)% when co-cultured with lung fibroblasts from idiopathic pulmonary fibrosis patients. The difference between the 2 groups was statistically significant(P=0.002 5). TGF-β receptor inhibitor SB431542 increased lung fibroblast growth factors FGF1/2 expression.FGF1 mRNA expression was increased to the experimental group 0.005 5 from 0.000 2 in the control group.FGF2 mRNA expression of the amount raised to the experimental group 0.000 15 from 0.000 8 in the control group.FGF1/2 promoted the growth of airway stem cells. After FGF1/2 was co-cultured with normal lung fibroblast cells for 8 days, the cloning efficiency of airway stem cells was (0.3±0.1)%. During the development of idiopathic pulmonary fibrosis, fibroblast secreted FGF1/2 regulate airway stem cell proliferation.

  19. Inhibition of aberrant circulating Tfh cell proportions by corticosteroids in patients with systemic lupus erythematosus.

    PubMed

    Feng, Xuebing; Wang, Dandan; Chen, Jingjing; Lu, Lin; Hua, Bingzhu; Li, Xia; Tsao, Betty P; Sun, Lingyun

    2012-01-01

    To observe the proportion of peripheral T follicular helper (Tfh) cells in patients with systemic lupus erythematosus (SLE) and to assess the role of steroids on Tfh cells from SLE patients. Peripheral blood mononuclear cells (PBMCs) from 42 SLE patients and 22 matched healthy subjects were collected to assess proportions of circulating CXCR5(+)PD1(+)/CD4(+) T cells (Tfh), CD4(+)CCR6(+) T cells (Th17-like) and CD19(+)CD138(+) plasma cells by flow cytometry. 8 of the patients had their blood redrawn within one week after receiving methylprednisolone pulse treatment. Disease activity was evaluated by SLE disease activity index. To test the effect of IL-21 and corticosteroids on Tfh cells in vitro, PBMCs harvested from another 15 SLE patients were cultured with medium, IL-21, or IL-21+ dexamethasone for 24 hours and 72 hours. PBMCs from an independent 23 SLE patients were cultured with different concentrations of dexamethasone for 24 hours. Compared to normal controls, percentages of circulating Tfh cells, but not Th17 cells, were elevated in SLE patients and correlated with disease activity. Proportions of Tfh cells in SLE patients were positively correlated with those of plasma cells and serum levels of antinuclear antibodies. After methylprednisolone pulse treatment, both percentages and absolute numbers of circulating Tfh cells were significantly decreased. In vitro cultures showed an increase of Tfh cell proportion after IL-21 stimulation that was totally abolished by the addition of dexamethasone. Both 0.5 and 1 µM dexamethasone decreased Tfh cells dose dependently (overall p = 0.013). We demonstrated that elevated circulating Tfh cell proportions in SLE patients correlated with their disease activities, and circulating levels of plasma cells and ANA. Corticosteroids treatment down-regulated aberrant circulating Tfh cell proportions both in vivo and in vitro, making Tfh cells a new treatment target for SLE patients.

  20. Proteomic Analysis Reveals Aberrant O-GlcNAcylation of Extracellular Proteins from Breast Cancer Cell Secretion.

    PubMed

    Netsirisawan, Pukkavadee; Chokchaichamnankit, Daranee; Srisomsap, Chantragan; Svasti, Jisnuson; Champattanachai, Voraratt

    2015-01-01

    O-GlcNAcylation is a unique intracellular protein modification; however, few extracellular O-GlcNAc-modified proteins have been discovered. We have previously demonstrated that many cellular proteins were aberrant in O-GlcNAcylation in breast cancer tissues. In the present study, therefore, we investigated whether O-GlcNAc-modified proteins were abnormally secreted from breast cancer cells. Intracellular and extracellular proteins were prepared from cell lysates of breast cancer cells (MCF-7 and MDA-MB-231) and normal breast cells (HMEC) and from their serum-free media (SFM), respectively. O-GlcNAcylation level was examined by immunoblotting. O-GlcNAc-Modified proteins were identified using two-dimensional gel electrophoresis and Liquid Chromatography-tandem Mass Spectrometry. O-GlcNAcylation level was significantly increased in the extracellular compartment of both types of cancer cells compared to normal cells. Interestingly, O-GlcNAc patterns differed between intracellular and extracellular proteins. Proteomic analysis revealed that many O-GlcNAc spots in MCF-7 secretions were abnormally increased in comparison to those in HMEC secretions. Among these, transitional endoplasmic reticulum ATPase (TER ATPase) and heat-shock 70 kDa (HSP70) were confirmed to be O-GlcNAc-modified. The levels of O-GlcNAc-HSP70 and O-GlcNAc-TER ATPase were higher in SFM from MCF-7 cells than in that from HMEC. O-GlcNAcomic study of the extracellular compartments reveals aberrant O-GlcNAc-secreted proteins, which may be of interest as potential biomarkers in breast cancer. Copyright© 2015, International Institute of Anticancer Research (Dr. John G. Delinasios), All rights reserved.

  1. Aberrant p63 and WT-1 expression in myoepithelial cells of pregnancy-associated breast cancer: implications for tumor aggressiveness and invasiveness

    PubMed Central

    Xu, Zheli; Wang, Wan; Deng, Chu-Xia; Man, Yan-gao

    2009-01-01

    Our recent studies revealed that focal alterations in breast myoepithelial cell layers significantly impact the biological presentation of associated epithelial cells. As pregnancy-associated breast cancer (PABC) has a significantly more aggressive clinical course and mortality rate than other forms of breast malignancies, our current study compared tumor suppressor expression in myoepithelial cells of PABC and non-PABC, to determine whether myoepithelial cells of PABC may have aberrant expression of tumor suppressors. Tissue sections from 20 cases of PABC and 20 cases of stage, grade, and age matched non-PABC were subjected to immunohistochemistry, and the expression of tumor suppressor maspin, p63, and Wilms' tumor 1 (WT-1) in calponin positive myoepithelial cells were statistically compared. The expression profiles of maspin, p63, and WT-1 in myoepithelial cells of all ducts encountered were similar between PABC and non-PABC. PABC, however, displayed several unique alterations in terminal duct and lobular units (TDLU), acini, and associated tumor tissues that were not seen in those of non-PABC, which included the absence of p63 and WT-1 expression in a vast majority of the myoepithelial cells, cytoplasmic localization of p63 in the entire epithelial cell population of some lobules, and substantially increasing WT-1 expression in vascular structures of the invasive cancer component. All or nearly all epithelial cells with aberrant p63 and WT-1 expression lacked the expression of estrogen receptor and progesterone receptor, whereas they had a substantially higher proliferation index than their counterparts with p63 and WT-1 expression. Hyperplastic cells with cytoplasmic p63 expression often adjacent to, and share a similar immunohistochemical and cytological profile with, invasive cancer cells. To our best knowledge, our main finings have not been previously reported. Our findings suggest that the functional status of myoepithelial cells may be significantly

  2. RBE of Energetic Iron Ions for the Induction of Early and Late Chromosome Aberrations in Different Cell Types

    NASA Technical Reports Server (NTRS)

    Zhang, Ye; Yeshitla, Samrawit; Hada, Megumi; Kadhim, Munira; Wilson, Bobby; Wu, Honglu

    2014-01-01

    Numerous published studies have reported the RBE values for chromosome chromosomes induced by charged particles of different LET. The RBE for chromosome aberrations in human lymphocytes exposed ex vivo showed a similar relationship as the quality factor for cancer induction. Consequently, increased chromosome aberrations in the astronauts' white blood cells post long-duration missions are used to determine the biological doses from exposures to space radiation. The RBE value is known to be very different for different types of cancer. Previously, we reported that the RBE for initial chromosome damages was high in human lymphocytes exposed to Fe ions. After multiple cell divisions post irradiation, the RBE was significantly smaller. To test the hypothesis that the RBE values for chromosome aberrations are different between early and late damages and also different between different cell types, we exposed human lymphocytes ex vivo, and human fibroblast cells and human mammary epithelial cells in vitro to 600 MeV/u Fe ions. Post irradiation, the cells were collected at first mitosis, or cultured for multiple generations for collections of remaining or late arising chromosome aberrations. The chromosome aberrations were quantified using fluorescent in situ hybridization (FISH) with whole chromosome specific probes. This study attempts to offer an explanation for the varying RBE values for different cancer types.

  3. Ethanol inhibits human bone cell proliferation and function in vitro

    SciTech Connect

    Friday, K.E.; Howard, G.A.

    1991-06-01

    The direct effects of ethanol on human bone cell proliferation and function were studied in vitro. Normal human osteoblasts from trabecular bone chips were prepared by collagenase digestion. Exposure of these osteoblasts to ethanol in concentrations of 0.05% to 1% for 22 hours induced a dose-dependent reduction in bone cell DNA synthesis as assessed by incorporation of 3H-thymidine. After 72 hours of ethanol exposure in concentrations of 0.01% to 1%, protein synthesis as measured by 3H-proline incorporation into trichbroacetic acid (TCA)-precipitable material was reduced in a dose-dependent manner. Human bone cell protein concentrations and alkaline phosphatase total activity were significantlymore » reduced after exposure to 1% ethanol for 72 hours, but not with lower concentrations of ethanol. This reduction in osteoblast proliferation and activity may partially explain the development of osteopenia in humans consuming excessive amounts of ethanol.« less

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

    SciTech Connect

    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

  5. M-BAND Study of Radiation-Induced Chromosome Aberrations in Human Epithelial Cells: Radiation Quality and Dose Rate Effects

    NASA Technical Reports Server (NTRS)

    Hada, Megumi; Cucinotta, Francis; Wu, Honglu

    2009-01-01

    The advantage of the multicolor banding in situ hybridization (mBAND) technique is its ability to identify both inter- (translocation to unpainted chromosomes) and intra- (inversions and deletions within a single painted chromosome) chromosome aberrations simultaneously. To study the detailed rearrangement of low- and high-LET radiation induced chromosome aberrations in human epithelial cells (CH184B5F5/M10) in vitro, we performed a series of experiments with Cs-137 gamma rays of both low and high dose rates, neutrons of low dose rate and 600 MeV/u Fe ions of high dose rate, with chromosome 3 painted with multi-binding colors. We also compared the chromosome aberrations in both 2- and 3-dimensional cell cultures. Results of these experiments revealed the highest chromosome aberration frequencies after low dose rate neutron exposures. However, detailed analysis of the radiation induced inversions revealed that all three radiation types induced a low incidence of simple inversions. Most of the inversions in gamma-ray irradiated samples were accompanied by other types of intra-chromosomal aberrations but few inversions were accompanied by inter-chromosomal aberrations. In contrast, neutrons and Fe ions induced a significant fraction of inversions that involved complex rearrangements of both inter- and intrachromosomal exchanges. The location of the breaks involved in chromosome exchanges was analyzed along the painted chromosome. The breakpoint distribution was found to be randomly localized on chromosome 3 after neutron or Fe ion exposure, whereas non-random distribution with clustering breakpoints was observed after -ray exposure. Our comparison of chromosome aberration yields between 2- and 3-dimensional cell cultures indicated a significant difference for gamma exposures, but not for Fe ion exposures. These experimental results indicated that the track structure of the radiation and the cellular/chromosome structure can both affect radiation-induced chromosome

  6. ERβ inhibits proliferation and invasion of breast cancer cells

    PubMed Central

    Lazennec, Gwendal; Bresson, Damien; Lucas, Annick; Chauveau, Corine; Vignon, Françoise

    2001-01-01

    Recent studies indicate that the expression of ERβ in breast cancer is lower than in normal breast, suggesting that ERβ could play an important role in carcinogenesis. To investigate this hypothesis, we engineered estrogen-receptor negative MDA-MB-231 breast cancer cells to reintroduce either ERα or ERβ protein with an adenoviral vector. In these cells, ERβ (as ERα) expression was monitored using RT-PCR and Western blot. ERβ protein was localized in the nucleus (immunocytochemistry) and able to transactivate estrogen-responsive reporter constructs in the presence of estradiol. ERβ and ERα induced the expression of several endogenous genes such as pS2, TGFα or the cyclin kinase inhibitor p21, but in contrast to ERα, ERβ was unable to regulate c-myc proto-oncogene expression. The pure antiestrogen ICI 164, 384 completely blocked ERα and ERβ estrogen-induced activities. ERβ inhibited MDA-MB-231 cell proliferation in a ligand-independent manner, whereas ERα inhibition of proliferation is hormone-dependent. Moreover, ERβ and ERα, decreased cell motility and invasion. Our data bring the first evidence that ERβ is an important modulator of proliferation and invasion of breast cancer cells and support the hypothesis that the loss of ERβ expression could be one of the events leading to the development of breast cancer. PMID:11517191

  7. 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

  8. C/EBPβ regulates homeostatic and oncogenic gastric cell proliferation.

    PubMed

    Regalo, Goncalo; Förster, Susann; Resende, Carlos; Bauer, Bianca; Fleige, Barbara; Kemmner, Wolfgang; Schlag, Peter M; Meyer, Thomas F; Machado, José C; Leutz, Achim

    2016-12-01

    Cancer of the stomach is among the leading causes of death from cancer worldwide. The transcription factor C/EBPβ is frequently overexpressed in gastric cancer and associated with the suppression of the differentiation marker TFF1. We show that the murine C/EBPβ knockout stomach displays unbalanced homeostasis and reduced cell proliferation and that tumorigenesis of human gastric cancer xenograft is inhibited by knockdown of C/EBPβ. Cross-species comparison of gene expression profiles between C/EBPβ-deficient murine stomach and human gastric cancer revealed a subset of tumors with a C/EBPβ signature. Within this signature, the RUNX1t1 tumor suppressor transcript was down-regulated in 38 % of gastric tumor samples. The RUNX1t1 promoter was frequently hypermethylated and ectopic expression of RUNX1t1 in gastric cancer cells inhibited proliferation and enhanced TFF1 expression. These data suggest that the tumor suppressor activity of both RUNX1t1 and TFF1 are mechanistically connected to C/EBPβ and that cross-regulation between C/EBPβ-RUNX1t1-TFF1 plays an important role in gastric carcinogenesis. C/EBPβ controls proliferation and differentiation balance in the stomach. Homeostatic differentiation/proliferation balance is altered in gastric cancer. RUNX1t1 is a C/EBPβ-associated tumor suppressor. RUNX1t1 negatively regulates C/EBPβ pro-oncogenic functions.

  9. The effect of track structure on the induction of chromosomal aberrations in murine cells.

    PubMed

    Durante, M; Cella, L; Furusawa, Y; George, K; Gialanella, G; Grossi, G; Pugliese, M; Saito, M; Yang, T C

    1998-03-01

    To measure chromosome aberrations in C3H 10T1/2 mouse fibroblasts using FISH painting at the first mitosis following exposure to 30 keV/microm hydrogen or neon ions. Cells in plateau-phase were irradiated with 0.86 MeV protons at the TTT-3 Tandem accelerator in Naples (Italy), or with 400 MeV/n Ne ions at the HIMAC accelerator in Chiba (Japan). Colcemid-blocked cells were harvested at the first mitosis following exposure, and chromosome spreads were hybridized in situ with a fluorescein-labelled composite mouse DNA probe specific for chromosomes 2 and 8. Protons were more efficient than neon ions at the same LET in the induction of chromosome interchanges and breaks. Yields of complex exchanges were similar for both particles at the same dose, but protons produced mostly insertions, while with Ne exposure non-reciprocal exchanges were the most frequent complex-type exchange. Charged particles with the same LET produce different yields of chromosome aberrations, and some observed differences can be explained based on the available track-structure models.

  10. The effect of track structure on the induction of chromosomal aberrations in murine cells

    NASA Technical Reports Server (NTRS)

    Durante, M.; Cella, L.; Furusawa, Y.; George, K.; Gialanella, G.; Grossi, G.; Pugliese, M.; Saito, M.; Yang, T. C.

    1998-01-01

    PURPOSE: To measure chromosome aberrations in C3H 10T1/2 mouse fibroblasts using FISH painting at the first mitosis following exposure to 30 keV/microm hydrogen or neon ions. MATERIALS AND METHODS: Cells in plateau-phase were irradiated with 0.86 MeV protons at the TTT-3 Tandem accelerator in Naples (Italy), or with 400 MeV/n Ne ions at the HIMAC accelerator in Chiba (Japan). Colcemid-blocked cells were harvested at the first mitosis following exposure, and chromosome spreads were hybridized in situ with a fluorescein-labelled composite mouse DNA probe specific for chromosomes 2 and 8. RESULTS: Protons were more efficient than neon ions at the same LET in the induction of chromosome interchanges and breaks. Yields of complex exchanges were similar for both particles at the same dose, but protons produced mostly insertions, while with Ne exposure non-reciprocal exchanges were the most frequent complex-type exchange. CONCLUSIONS: Charged particles with the same LET produce different yields of chromosome aberrations, and some observed differences can be explained based on the available track-structure models.

  11. Fascin Overexpression Promotes Cholangiocarcinoma RBE Cell Proliferation, Migration, and Invasion.

    PubMed

    Zhao, Haiying; Yang, Fuquan; Zhao, Wenyan; Zhang, Chunjv; Liu, Jingang

    2016-04-01

    Fascin is overexpressed in various tumor tissues and is closely related to tumor metastasis and invasion. However, the role of fascin in cholangiocarcinoma RBE cells has not been clearly reported. This study aimed to establish a cholangiocarcinoma cell line with stable and high expression of fascin to observe the effect of fascin on cell proliferation, migration, and invasion. A fascin overexpression vector, pcDNA3.1-Fascin, was constructed and transfected into the human cholangiocarcinoma RBE cell line. The results of real-time polymerase chain reaction, Western blot, and immunofluorescence indicated that fascin was steadily and highly expressed in RBE cells. The results of 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide and colony formation assay indicated that upregulated fascin expression could enhance cholangiocarcinoma cell proliferation. The results of wound healing assay and transwell assay indicated that fascin could promote cholangiocarcinoma cell migration and invasion, and a further study found that the nuclear factor-κB signaling pathway was activated after upregulation of fascin, whereas E-cadherin expression in these cells was significantly decreased. Additionally, E-cadherin expression was significantly increased after inhibiting nuclear factor-κB activity using inhibitor or small interfering RNA, and E-cadherin expression was decreased by fascin overexpression after nuclear factor-κB inhibition, suggesting that nuclear factor-κB signaling pathway was not involved in the regulation of E-cadherin by fascin. In summary, the results of this study demonstrated that fascin effectively promoted cholangiocarcinoma RBE cell proliferation, migration, and invasion. This study provides evidence for fascin as a potential target in the treatment of cholangiocarcinoma. © The Author(s) 2015.

  12. Daucosterol promotes the proliferation of neural stem cells.

    PubMed

    Jiang, Li-hua; Yang, Nian-yun; Yuan, Xiao-lin; Zou, Yi-jie; Zhao, Feng-ming; Chen, Jian-ping; Wang, Ming-yan; Lu, Da-xiang

    2014-03-01

    Neural stem cells (NSCs) are self-regenerating cells, but their regenerative capacity is limited. The present study was conducted to investigate the effect of daucosterol (a sterolin) on the promotion of NSC proliferation and determine the corresponding molecular mechanism. Results of cell counting kit-8 (CCK-8) assay showed that daucosterol significantly increased the quantity of viable cells and the effectiveness of daucosterol was similar to that of basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF). Flow cytometry detection of CFSE-labeled (CFSE, carboxyfluorescein diacetate succinimidyl ester) NSCs showed that Div Index (or the average number of cell divisions) and % Divided (or the percentage of cells that divided at least once) of the cells were increased, indicating that daucosterol increased the percentage of NSCs re-entering the cell cycle. mRNA microarray analysis showed that 333 genes that are mostly involved in the mitotic cell cycle were up-regulated. By contrast, 627 genes that are mostly involved in differentiation were down-regulated. In particular, insulin-like growth factor I (IGF1) was considered as an important regulatory gene that functionally promoted NSC proliferation, and the increased expression of IGF1 protein was validated by ELISA. In addition, the phosphorylation of AKT was increased, indicating that the proliferation-enhancing activity of daucosterol may be involved in IGF1-AKT pathway. Our study provided information about daucosterol as an efficient and inexpensive growth factor alternative that could be used in clinical medicine and research applications. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  13. 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

  14. Genetic abolishment of hepatocyte proliferation activates hepatic stem cells.

    PubMed

    Endo, Yoko; Zhang, Mingjun; Yamaji, Sachie; Cang, Yong

    2012-01-01

    Quiescent hepatic stem cells (HSCs) can be activated when hepatocyte proliferation is compromised. Chemical injury rodent models have been widely used to study the localization, biomarkers, and signaling pathways in HSCs, but these models usually exhibit severe promiscuous toxicity and fail to distinguish damaged and non-damaged cells. Our goal is to establish new animal models to overcome these limitations, thereby providing new insights into HSC biology and application. We generated mutant mice with constitutive or inducible deletion of Damaged DNA Binding protein 1 (DDB1), an E3 ubiquitin ligase, in hepatocytes. We characterized the molecular mechanism underlying the compensatory activation and the properties of oval cells (OCs) by methods of mouse genetics, immuno-staining, cell transplantation and gene expression profiling. We show that deletion of DDB1 abolishes self-renewal capacity of mouse hepatocytes in vivo, leading to compensatory activation and proliferation of DDB1-expressing OCs. Partially restoring proliferation of DDB1-deficient hepatocytes by ablation of p21, a substrate of DDB1 E3 ligase, alleviates OC proliferation. Purified OCs express both hepatocyte and cholangiocyte markers, form colonies in vitro, and differentiate to hepatocytes after transplantation. Importantly, the DDB1 mutant mice exhibit very minor liver damage, compared to a chemical injury model. Microarray analysis reveals several previously unrecognized markers, including Reelin, enriched in oval cells. Here we report a genetic model in which irreversible inhibition of hepatocyte duplication results in HSC-driven liver regeneration. The DDB1 mutant mice can be broadly applied to studies of HSC differentiation, HSC niche and HSCs as origin of liver cancer.

  15. Genetic Abolishment of Hepatocyte Proliferation Activates Hepatic Stem Cells

    PubMed Central

    Endo, Yoko; Zhang, Mingjun; Yamaji, Sachie; Cang, Yong

    2012-01-01

    Quiescent hepatic stem cells (HSCs) can be activated when hepatocyte proliferation is compromised. Chemical injury rodent models have been widely used to study the localization, biomarkers, and signaling pathways in HSCs, but these models usually exhibit severe promiscuous toxicity and fail to distinguish damaged and non-damaged cells. Our goal is to establish new animal models to overcome these limitations, thereby providing new insights into HSC biology and application. We generated mutant mice with constitutive or inducible deletion of Damaged DNA Binding protein 1 (DDB1), an E3 ubiquitin ligase, in hepatocytes. We characterized the molecular mechanism underlying the compensatory activation and the properties of oval cells (OCs) by methods of mouse genetics, immuno-staining, cell transplantation and gene expression profiling. We show that deletion of DDB1 abolishes self-renewal capacity of mouse hepatocytes in vivo, leading to compensatory activation and proliferation of DDB1-expressing OCs. Partially restoring proliferation of DDB1-deficient hepatocytes by ablation of p21, a substrate of DDB1 E3 ligase, alleviates OC proliferation. Purified OCs express both hepatocyte and cholangiocyte markers, form colonies in vitro, and differentiate to hepatocytes after transplantation. Importantly, the DDB1 mutant mice exhibit very minor liver damage, compared to a chemical injury model. Microarray analysis reveals several previously unrecognized markers, including Reelin, enriched in oval cells. Here we report a genetic model in which irreversible inhibition of hepatocyte duplication results in HSC-driven liver regeneration. The DDB1 mutant mice can be broadly applied to studies of HSC differentiation, HSC niche and HSCs as origin of liver cancer. PMID:22384083

  16. Effects of electrical stimulation on cell proliferation and apoptosis.

    PubMed

    Love, Maria R; Palee, Siripong; Chattipakorn, Siriporn C; Chattipakorn, Nipon

    2018-03-01

    The application of exogenous electrical stimulation (ES) to cells in order to manipulate cell apoptosis and proliferation has been widely investigated as a possible method of treatment in a number of diseases. Alteration of the transmembrane potential of cells via ES can affect various intracellular signaling pathways which are involved in the regulation of cellular function. Controversially, several types of ES have proved to be effective in both inhibiting or inducing apoptosis, as well as increasing proliferation. However, the mechanisms through which ES achieves this remain fairly unclear. The aim of this review was to comprehensively summarize current findings from in vitro and in vivo studies on the effects of different types of ES on cell apoptosis and proliferation, highlighting the possible mechanisms through which ES induced these effects and define the optimum parameters at which ES can be used. Through this we hope to provide a greater insight into how future studies can most effectively use ES at the clinical trial stage. © 2017 Wiley Periodicals, Inc.

  17. Angiotensin Converting Enzyme Regulates Cell Proliferation and Migration

    PubMed Central

    Carvalho, Clarissa Coelho; Florentino, Rodrigo Machado; França, Andressa; Matias, Eveline; Guimarães, Paola Bianchi; Batista, Carolina; Freire, Valder; Carmona, Adriana Karaoglanovic; Pesquero, João Bosco; de Paula, Ana Maria; Foureaux, Giselle; Leite, Maria de Fatima

    2016-01-01

    Background The angiotensin-I converting enzyme (ACE) plays a central role in the renin-angiotensin system, acting by converting the hormone angiotensin-I to the active peptide angiotensin-II (Ang-II). More recently, ACE was shown to act as a receptor for Ang-II, and its expression level was demonstrated to be higher in melanoma cells compared to their normal counterparts. However, the function that ACE plays as an Ang-II receptor in melanoma cells has not been defined yet. Aim Therefore, our aim was to examine the role of ACE in tumor cell proliferation and migration. Results We found that upon binding to ACE, Ang-II internalizes with a faster onset compared to the binding of Ang-II to its classical AT1 receptor. We also found that the complex Ang-II/ACE translocates to the nucleus, through a clathrin-mediated process, triggering a transient nuclear Ca2+ signal. In silico studies revealed a possible interaction site between ACE and phospholipase C (PLC), and experimental results in CHO cells, demonstrated that the β3 isoform of PLC is the one involved in the Ca2+ signals induced by Ang-II/ACE interaction. Further studies in melanoma cells (TM-5) showed that Ang-II induced cell proliferation through ACE activation, an event that could be inhibited either by ACE inhibitor (Lisinopril) or by the silencing of ACE. In addition, we found that stimulation of ACE by Ang-II caused the melanoma cells to migrate, at least in part due to decreased vinculin expression, a focal adhesion structural protein. Conclusion ACE activation regulates melanoma cell proliferation and migration. PMID:27992423

  18. Chromosomal Aberrations and Survival after Unrelated Donor Hematopoietic Stem Cell Transplant in Patients with Fanconi Anemia.

    PubMed

    Wang, Youjin; Zhou, Weiyin; Alter, Blanche P; Wang, Tao; Spellman, Stephen R; Haagenson, Michael; Yeager, Meredith; Lee, Stephanie J; Chanock, Stephen J; Savage, Sharon A; Gadalla, Shahinaz M

    2018-06-04

    Studies of chromosomal aberrations in blood or bone marrow of patients with Fanconi anemia (FA) have focused on their associations with leukemic transformation. The role of such abnormalities on outcomes after hematopoietic cell transplantation (HCT) is unclear. We used genome-wide single nucleotide polymorphism arrays to identify chromosomal aberrations in pre-HCT blood samples from 73 patients with FA who received unrelated donor HCT for severe aplastic anemia between 1991 and 2007. Outcome data and blood samples were available through the Center for International Blood and Marrow Transplant Research. For survival analyses, we used the Kaplan-Meier estimator to calculate the survival probabilities and the exact log-rank test to compare the survival differences across groups. Chromosomal aberrations were detected in 16 (22%) patients; most frequent were clonal copy loss in chromosome 7 (9.6%), clonal copy gains in the long arm (q) of chromosome 1 (chr1q + ) (8.2%), and clonal or complete copy gains in the q arm of chromosome 3 (chr3q + ) (8.2%). Seven (9.6%) patients had alterations in 3 or more chromosomes. Poor post-HCT overall survival (OS) was noted in patients with chr3q +  (P = .04), or those with abnormalities in ≥3 chromosomes (P = .03). The 1-year OS was 0% versus 45% in patients with either alteration versus its absence. No statistically significant differences in 1-year OS were noted in patients carrying deletions in chr7 (29% versus 42%; log-rank P = .74). The study is limited by the small sample size. A larger, prospective study is warranted to validate our findings in light of recent improvement in transplant modalities and outcomes. Copyright © 2018. Published by Elsevier Inc.

  19. Social Competition in Rats: Cell Proliferation and Behavior

    PubMed Central

    Hoshaw, Brian A.; Evans, Jennifer C.; Mueller, Bridget; Valentino, Rita J.; Lucki, Irwin

    2007-01-01

    Behavioral and physiological changes were studied following prolonged exposure to social competition in pairs of non food-deprived rats competing daily for a limited supply of graham cracker crumbs. Stable dominant-subordinate relationships developed in most pairs, as measured by feeding time, which were maintained over a 5–6-week study period. In other behavioral tests, subordinates demonstrated a decreased latency to immobility in the forced swim test compared with dominants, but no difference in locomotor activity. Subordinates had increased bladder size, decreased adrenal gland size, and a 35% reduction of hippocampus cell proliferation compared with the dominant member. Therefore, prolonged social competition, based on restricted access to palatable substances, produced hierarchies among individuals that were associated with differences in behavior, physiology and hippocampal cell proliferation. PMID:17045347

  20. 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.

  1. Chromosomal aberrations and delays in cell progression induced by x-rays in Tradescantia clone 02 meristems

    SciTech Connect

    Geard, C.R.

    1983-01-01

    In root meristems of Tradescantia clone 02 (developed by Sparrow and his colleagues for mutation studies), X-rays interfere with the progression of cells through the cell cycle and induce chromosomal aberrations in a dose-dependent manner consistent with linear-quadratic kinetics. Sequential mitotic cell accumulations after irradiation indicate that sensitivity to aberrration induction is probably greatest in cells from late S to early G2, with chromatid interchanges the most frequent aberration type and all aberrations consistent with intiation from the interaction between two lesions. The ratio of the coefficients in the linear (..cap alpha..) and the quadratic (..beta..) terms (..cap alpha../..beta..) ismore » equal to the dose average of specific energy produced by individual particles in the site where interaction takes place. The ratio ..cap alpha../..beta.. for chromosomal aberrations is similar to that previously found for X-ray-induced mutation in Tradescantia stamen hairs, supporting the proposal that radiation-induced mutational events are due to chromosomal aberrations with interaction distances of about 1 ..mu..m. Abrahmson and co-workers have noted that both ..cap alpha../..beta.. ratios appear to be related to nuclear target size and are similar for chromosomal and mutational endpoints in the same organism. These findings support this concept; however, it is apparent that any situation which diminishes yield at high doses (e.g., mitotic delay) will primarily affect the ..beta.. component, resulting in low assessments of interaction site diameters.« less

  2. Aberrant Gene Expression Profiles in Pluripotent Stem Cells Induced from Fibroblasts of a Klinefelter Syndrome Patient*

    PubMed Central

    Ma, Yu; Li, Chunliang; Gu, Junjie; Tang, Fan; Li, Chun; Li, Peng; Ping, Ping; Yang, Shi; Li, Zheng; Jin, Ying

    2012-01-01

    Klinefelter syndrome (KS) is the most common male chromosome aneuploidy. Its pathophysiology is largely unexplained due to the lack of adequate models. Here, we report the derivation of induced pluripotent stem cell (iPSCs) lines from a KS patient with a karyotype of 47, XXY. Derived KS-iPSCs meet all criteria of normal iPSCs with the potential for germ cell differentiation. Although X chromosome inactivation occurs in all KS-iPSCs, genome-wide transcriptome analysis identifies aberrantly expressed genes associated with the clinical features of KS. Our KS-iPSCs can serve as a cellular model for KS research. Identified genes may become biomarkers for early diagnosis or potential therapeutic targets for KS and significantly accelerate the understanding, diagnosis, and treatment of Klinefelter syndrome. PMID:23019320

  3. Nuclear orphan receptor TLX affects gene expression, proliferation and cell apoptosis in beta cells

    SciTech Connect

    Shi, Xiaoli; Xiong, Xiaokan; Dai, Zhe

    2015-12-04

    Nuclear orphan receptor TLX is an essential regulator of the growth of neural stem cells. However, its exact function in pancreatic islet cells is still unknown. In the present study, gene expression profiling analysis revealed that overexpression of TLX in beta cell line MIN6 causes suppression of 176 genes and upregulation of 49 genes, including a cadre of cell cycle, cell proliferation and cell death control genes, such as Btg2, Ddit3 and Gadd45a. We next examined the effects of TLX overexpression on proliferation, apoptosis and insulin secretion in MIN6 cells. Proliferation analysis using EdU assay showed that overexpression of TLXmore » increased percentage of EdU-positive cells. Cell cycle and apoptosis analysis revealed that overexpression of TLX in MIN6 cells resulted in higher percentage of cells exiting G1 into S-phase, and a 58.8% decrease of cell apoptosis induced by 0.5 mM palmitate. Moreover, TLX overexpression did not cause impairment of insulin secretion. Together, we conclude that TLX is among factors capable of controlling beta cell proliferation and survival, which may serve as a target for the development of novel therapies for diabetes. - Highlights: • TLX overexpression in MIN6 cell causes significant expression changes of 225 genes. • TLX overexpression promotes MIN6 cell proliferation and decreases cell apoptosis. • TLX overexpression does not cause impairment of insulin secretion.« less

  4. 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.

  5. Co-culture with Sertoli cells promotes proliferation and migration of umbilical cord mesenchymal stem cells

    SciTech Connect

    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

  6. MiR-509-3-5p causes aberrant mitosis and anti-proliferative effect by suppression of PLK1 in human lung cancer A549 cells

    SciTech Connect

    Wang, Xian-Hui; Lu, Yao; Liang, Jing-Jing

    MicroRNAs (miRNAs) are potent post-transcriptional regulators of gene expression and play roles in DNA damage response (DDR). PLK1 is identified as a modulator of DNA damage checkpoint. Although down-regulation of PLK1 by certain microRNAs has been reported, little is known about the interplay between PLK1 and miR-509-3-5p in DDR. Here we have demonstrated that miR-509-3-5p repressed PLK1 expression by targeting PLK1 3′-UTR, thereby causing mitotic aberration and growth arrest of human lung cancer A549 cells. Repression of PLK1 by miR-509-3-5p was further evidenced by over-expression of miR-509-3-5p in A549, HepG2 and HCT116p53{sup −/−} cancer cells, in which PLK1 protein wasmore » suppressed. Consistently, miR-509-3-5p was stimulated, while PLK1 protein was down-regulated in A549 cells exposed to CIS and ADR, suggesting that suppression of PLK1 by miR-509-3-5p is a component of CIS/ADR-induced DDR pathway. Flow cytometry and immunofluorescence labeling showed that over-expression of miR-509-3-5p in A549 induced G2/M arrest and aberrant mitosis characterized by abnormal bipolar mitotic spindles, condensed chromosomes, lagging DNA and chromosome bridges. In addition, over-expression of miR-509-3-5p markedly blocked A549 cell proliferation and sensitized the cells to CIS and ADR treatment. Taken together, miR-509-3-5p is a feasible suppressor for cancer by targeting PLK1. Our data may provide aid in potential design of combined chemotherapy and in our better understanding of the roles of microRNAs in response to DNA damage. - Highlights: • MiR-509-3-5p represses PLK1 expression by targeting PLK1 3ГЉВ№-UTR. • Expression of miR-509-3-5p is induced and PLK1 repressed upon DNA damage. • Overexpression of miR-509-3-5p induces G2/M arrest and aberrant mitosis. • MiR-509-3-5p inhibits cell proliferation and sensitizes cells to DNA damage agents.« less

  7. Aberration-free FTIR spectroscopic imaging of live cells in microfluidic devices.

    PubMed

    Chan, K L Andrew; Kazarian, Sergei G

    2013-07-21

    The label-free, non-destructive chemical analysis offered by FTIR spectroscopic imaging is a very attractive and potentially powerful tool for studies of live biological cells. FTIR imaging of live cells is a challenging task, due to the fact that cells are cultured in an aqueous environment. While the synchrotron facility has proven to be a valuable tool for FTIR microspectroscopic studies of single live cells, we have demonstrated that high quality infrared spectra of single live cells using an ordinary Globar source can also be obtained by adding a pair of lenses to a common transmission liquid cell. The lenses, when placed on the transmission cell window, form pseudo hemispheres which removes the refraction of light and hence improve the imaging and spectral quality of the obtained data. This study demonstrates that infrared spectra of single live cells can be obtained without the focus shifting effect at different wavenumbers, caused by the chromatic aberration. Spectra of the single cells have confirmed that the measured spectral region remains in focus across the whole range, while spectra of the single cells measured without the lenses have shown some erroneous features as a result of the shift of focus. It has also been demonstrated that the addition of lenses can be applied to the imaging of cells in microfabricated devices. We have shown that it was not possible to obtain a focused image of an isolated cell in a droplet of DPBS in oil unless the lenses are applied. The use of the approach described herein allows for well focused images of single cells in DPBS droplets to be obtained.

  8. Uncaria tomentosa stimulates the proliferation of myeloid progenitor cells.

    PubMed

    Farias, Iria; do Carmo Araújo, Maria; Zimmermann, Estevan Sonego; Dalmora, Sergio Luiz; Benedetti, Aloisio Luiz; Alvarez-Silva, Marcio; Asbahr, Ana Carolina Cavazzin; Bertol, Gustavo; Farias, Júlia; Schetinger, Maria Rosa Chitolina

    2011-09-01

    The Asháninkas, indigenous people of Peru, use cat's claw (Uncaria tomentosa) to restore health. Uncaria tomentosa has antioxidant activity and works as an agent to repair DNA damage. It causes different effects on cell proliferation depending on the cell type involved; specifically, it can stimulate the proliferation of myeloid progenitors and cause apoptosis of neoplastic cells. Neutropenia is the most common collateral effect of chemotherapy. For patients undergoing cancer treatment, the administration of a drug that stimulates the proliferation of healthy hematopoietic tissue cells is very desirable. It is important to assess the acute effects of Uncaria tomentosa on granulocyte-macrophage colony-forming cells (CFU-GM) and in the recovery of neutrophils after chemotherapy-induced neutropenia, by establishing the correlation with filgrastim (rhG-CSF) treatment to evaluate its possible use in clinical oncology. The in vivo assay was performed in ifosfamide-treated mice receiving oral doses of 5 and 15 mg of Uncaria tomentosa and intraperitoneal doses of 3 and 9 μg of filgrastim, respectively, for four days. Colony-forming cell (CFC) assays were performed with human hematopoietic stem/precursor cells (hHSPCs) obtained from umbilical cord blood (UCB). Bioassays showed that treatment with Uncaria tomentosa significantly increased the neutrophil count, and a potency of 85.2% was calculated in relation to filgrastim at the corresponding doses tested. An in vitro CFC assay showed an increase in CFU-GM size and mixed colonies (CFU-GEMM) size at the final concentrations of 100 and 200 μg extract/mL. At the tested doses, Uncaria tomentosa had a positive effect on myeloid progenitor number and is promising for use with chemotherapy to minimize the adverse effects of this treatment. These results support the belief of the Asháninkas, who have classified Uncaria tomentosa as a 'powerful plant'. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  9. Reversal of hepatocyte senescence after continuous in vivo cell proliferation.

    PubMed

    Wang, Min-Jun; Chen, Fei; Li, Jian-Xiu; Liu, Chang-Cheng; Zhang, Hai-Bin; Xia, Yong; Yu, Bing; You, Pu; Xiang, Dao; Lu, Lian; Yao, Hao; Borjigin, Uyunbilig; Yang, Guang-Shun; Wangensteen, Kirk J; He, Zhi-Ying; Wang, Xin; Hu, Yi-Ping

    2014-07-01

    A better understanding of hepatocyte senescence could be used to treat age-dependent disease processes of the liver. Whether continuously proliferating hepatocytes could avoid or reverse senescence has not yet been fully elucidated. We confirmed that the livers of aged mice accumulated senescent and polyploid hepatocytes, which is associated with accumulation of DNA damage and activation of p53-p21 and p16(ink4a)-pRB pathways. Induction of multiple rounds continuous cell division is hard to apply in any animal model. Taking advantage of serial hepatocyte transplantation assays in the fumarylacetoacetate hydrolase-deficient (Fah(-/-)) mouse, we studied the senescence of hepatocytes that had undergone continuous cell proliferation over a long time period, up to 12 rounds of serial transplantations. We demonstrated that the continuously proliferating hepatocytes avoided senescence and always maintained a youthful state. The reactivation of telomerase in hepatocytes after serial transplantation correlated with reversal of senescence. Moreover, senescent hepatocytes harvested from aged mice became rejuvenated upon serial transplantation, with full restoration of proliferative capacity. The same findings were also true for human hepatocytes. After serial transplantation, the high initial proportion of octoploid hepatocytes decreased to match the low level of youthful liver. These findings suggest that the hepatocyte "ploidy conveyer" is regulated differently during aging and regeneration. The findings of reversal of hepatocyte senescence could enable future studies on liver aging and cell therapy. © 2014 by the American Association for the Study of Liver Diseases.

  10. Dendritic cells modulate burn wound healing by enhancing early proliferation.

    PubMed

    Vinish, Monika; Cui, Weihua; Stafford, Eboni; Bae, Leon; Hawkins, Hal; Cox, Robert; Toliver-Kinsky, Tracy

    2016-01-01

    Adequate wound healing is vital for burn patients to reduce the risk of infections and prolonged hospitalization. Dendritic cells (DCs) are antigen presenting cells that release cytokines and are central for the activation of innate and acquired immune responses. Studies have showed their presence in human burn wounds; however, their role in burn wound healing remains to be determined. This study investigated the role of DCs in modulating healing responses within the burn wound. A murine model of full-thickness contact burns was used to study wound healing in the absence of DCs (CD11c promoter-driven diphtheria toxin receptor transgenic mice) and in a DC-rich environment (using fms-like tyrosine kinase-3 ligand, FL- a DC growth factor). Wound closure was significantly delayed in DC-deficient mice and was associated with significant suppression of early cellular proliferation, granulation tissue formation, wound levels of TGFβ1 and formation of CD31+ vessels in healing wounds. In contrast, DC enhancement significantly accelerated early wound closure, associated with increased and accelerated cellular proliferation, granulation tissue formation, and increased TGFβ1 levels and CD31+ vessels in healing wounds. We conclude that DCs play an important role in the acceleration of early wound healing events, likely by secreting factors that trigger the proliferation of cells that mediate wound healing. Therefore, pharmacological enhancement of DCs may provide a therapeutic intervention to facilitate healing of burn wounds. © 2016 by the Wound Healing Society.

  11. Cell proliferation during hair cell regeneration induced by Math1 in vestibular epithelia in vitro

    PubMed Central

    Huang, Yi-bo; Ma, Rui; Yang, Juan-mei; Han, Zhao; Cong, Ning; Gao, Zhen; Ren, Dongdong; Wang, Jing; Chi, Fang-lu

    2018-01-01

    Hair cell regeneration is the fundamental method of correcting hearing loss and balance disorders caused by hair cell damage or loss. How to promote hair cell regeneration is a hot focus in current research. In mammals, cochlear hair cells cannot be regenerated and few vestibular hair cells can be renewed through spontaneous regeneration. However, Math1 gene transfer allows a few inner ear cells to be transformed into hair cells in vitro or in vivo. Hair cells can be renewed through two possible means in birds: supporting cell differentiation and transdifferentiation with or without cell division. Hair cell regeneration is strongly associated with cell proliferation. Therefore, this study explored the relationship between Math1-induced vestibular hair cell regeneration and cell division in mammals. The mouse vestibule was isolated to harvest vestibular epithelial cells. Ad-Math1-enhanced green fluorescent protein (EGFP) was used to track cell division during hair cell transformation. 5-Bromo-2′-deoxyuridine (BrdU) was added to track cell proliferation at various time points. Immunocytochemistry was utilized to determine cell differentiation and proliferation. Results demonstrated that when epithelial cells were in a higher proliferative stage, more of these cells differentiated into hair cells by Math1 gene transfer. However, in the low proliferation stage, no BrdU-positive cells were seen after Math1 gene transfer. Cell division always occurred before Math1 transfection but not during or after Math1 transfection, when cells were labeled with BrdU before and after Ad-Math1-EGFP transfection. These results confirm that vestibular epithelial cells with high proliferative potential can differentiate into new hair cells by Math1 gene transfer, but this process is independent of cell proliferation. PMID:29623936

  12. Nuclear abnormalities in aspirated thyroid cells and chromosome aberrations in lymphocytes of residents near the Semipalatinsk nuclear test site.

    PubMed

    Takeichi, Nobuo; Hoshi, Masaharu; Iida, Shozo; Tanaka, Kimio; Harada, Yuka; Zhumadilov, Zhaxybay; Chaizhunusova, Nailya; Apsalikov, Kazbek N; Noso, Yoshihiro; Inaba, Toshiya; Tanaka, Kenichi; Endo, Satoru

    2006-02-01

    Chromosomal studies in peripheral lymphocytes from 63 residents near the Semipalatinsk nuclear test site, at ages of 52-63 years old, were performed in 2001-2002. A higher rate of chromosome aberrations was observed in the two contaminated villages, Dolon and Sarjal, compared with the control village, Kokpekti. Moreover, a relationship of frequency of cells with radiation induced chromosome aberrations and the previously estimated exposure dose was observed. Furthermore, apparent nuclear abnormalities (ANA) of thyroid follicular cells were studied in 30 out of 63 residents, who were examined for chromosome aberrations. A higher rate of ANA was also found in the residents in the exposed villages compared with those in the control village. These results suggest radiation effects both on the chromosomes in peripheral lymphocytes and on the follicular cells in the thyroid.

  13. Bmi1 regulates murine intestinal stem cell proliferation and self-renewal downstream of Notch.

    PubMed

    López-Arribillaga, Erika; Rodilla, Verónica; Pellegrinet, Luca; Guiu, Jordi; Iglesias, Mar; Roman, Angel Carlos; Gutarra, Susana; González, Susana; Muñoz-Cánoves, Pura; Fernández-Salguero, Pedro; Radtke, Freddy; Bigas, Anna; Espinosa, Lluís

    2015-01-01

    Genetic data indicate that abrogation of Notch-Rbpj or Wnt-β-catenin pathways results in the loss of the intestinal stem cells (ISCs). However, whether the effect of Notch is direct or due to the aberrant differentiation of the transit-amplifying cells into post-mitotic goblet cells is unknown. To address this issue, we have generated composite tamoxifen-inducible intestine-specific genetic mouse models and analyzed the expression of intestinal differentiation markers. Importantly, we found that activation of β-catenin partially rescues the differentiation phenotype of Rbpj deletion mutants, but not the loss of the ISC compartment. Moreover, we identified Bmi1, which is expressed in the ISC and progenitor compartments, as a gene that is co-regulated by Notch and β-catenin. Loss of Bmi1 resulted in reduced proliferation in the ISC compartment accompanied by p16(INK4a) and p19(ARF) (splice variants of Cdkn2a) accumulation, and increased differentiation to the post-mitotic goblet cell lineage that partially mimics Notch loss-of-function defects. Finally, we provide evidence that Bmi1 contributes to ISC self-renewal. © 2015. Published by The Company of Biologists Ltd.

  14. Aberrant DNA methylation at genes associated with a stem cell-like phenotype in cholangiocarcinoma tumours

    PubMed Central

    Dai, Wei; Siddiq, Afshan; Walley, Andrew J; Limpaiboon, Temduang; Brown, Robert

    2013-01-01

    Genetic abnormalities of cholangiocarcinoma have been widely studied; however, epigenomic changes related to cholangiocarcinogenesis have been less well characterised. We have profiled the DNA methylomes of 28 primary cholangiocarcinoma and six matched adjacent normal tissues using Infinium’s HumanMethylation27 BeadChips with the aim of identifying gene sets aberrantly epigenetically regulated in this tumour type. Using a linear model for microarray data we identified 1610 differentially methylated autosomal CpG sites with 809 CpG sites (representing 603 genes) being hypermethylated and 801 CpG sites (representing 712 genes) being hypomethylated in cholangiocarcinoma versus adjacent normal tissues (false discovery rate ≤ 0.05). Gene ontology and gene set enrichment analyses identified gene sets significantly associated with hypermethylation at linked CpG sites in cholangiocarcinoma including homeobox genes and target genes of PRC2, EED, SUZ12 and histone H3 trimethylation at lysine 27. We confirmed frequent hypermethylation at the homeobox genes HOXA9 and HOXD9 by bisulfite pyrosequencing in a larger cohort of cholangiocarcinoma (n = 102). Our findings indicate a key role for hypermethylation of multiple CpG sites at genes associated with a stem cell-like phenotype as a common molecular aberration in cholangiocarcinoma. These data have implications for cholangiocarcinogenesis, as well as possible novel treatment options using histone methyltransferase inhibitors. PMID:24089088

  15. Identification of aberrant gene expression associated with aberrant promoter methylation in primordial germ cells between E13 and E16 rat F3 generation vinclozolin lineage

    PubMed Central

    2015-01-01

    Background Transgenerational epigenetics (TGE) are currently considered important in disease, but the mechanisms involved are not yet fully understood. TGE abnormalities expected to cause disease are likely to be initiated during development and to be mediated by aberrant gene expression associated with aberrant promoter methylation that is heritable between generations. However, because methylation is removed and then re-established during development, it is not easy to identify promoter methylation abnormalities by comparing normal lineages with those expected to exhibit TGE abnormalities. Methods This study applied the recently proposed principal component analysis (PCA)-based unsupervised feature extraction to previously reported and publically available gene expression/promoter methylation profiles of rat primordial germ cells, between E13 and E16 of the F3 generation vinclozolin lineage that are expected to exhibit TGE abnormalities, to identify multiple genes that exhibited aberrant gene expression/promoter methylation during development. Results The biological feasibility of the identified genes were tested via enrichment analyses of various biological concepts including pathway analysis, gene ontology terms and protein-protein interactions. All validations suggested superiority of the proposed method over three conventional and popular supervised methods that employed t test, limma and significance analysis of microarrays, respectively. The identified genes were globally related to tumors, the prostate, kidney, testis and the immune system and were previously reported to be related to various diseases caused by TGE. Conclusions Among the genes reported by PCA-based unsupervised feature extraction, we propose that chemokine signaling pathways and leucine rich repeat proteins are key factors that initiate transgenerational epigenetic-mediated diseases, because multiple genes included in these two categories were identified in this study. PMID:26677731

  16. Identification of aberrant gene expression associated with aberrant promoter methylation in primordial germ cells between E13 and E16 rat F3 generation vinclozolin lineage.

    PubMed

    Taguchi, Y-h

    2015-01-01

    Transgenerational epigenetics (TGE) are currently considered important in disease, but the mechanisms involved are not yet fully understood. TGE abnormalities expected to cause disease are likely to be initiated during development and to be mediated by aberrant gene expression associated with aberrant promoter methylation that is heritable between generations. However, because methylation is removed and then re-established during development, it is not easy to identify promoter methylation abnormalities by comparing normal lineages with those expected to exhibit TGE abnormalities. This study applied the recently proposed principal component analysis (PCA)-based unsupervised feature extraction to previously reported and publically available gene expression/promoter methylation profiles of rat primordial germ cells, between E13 and E16 of the F3 generation vinclozolin lineage that are expected to exhibit TGE abnormalities, to identify multiple genes that exhibited aberrant gene expression/promoter methylation during development. The biological feasibility of the identified genes were tested via enrichment analyses of various biological concepts including pathway analysis, gene ontology terms and protein-protein interactions. All validations suggested superiority of the proposed method over three conventional and popular supervised methods that employed t test, limma and significance analysis of microarrays, respectively. The identified genes were globally related to tumors, the prostate, kidney, testis and the immune system and were previously reported to be related to various diseases caused by TGE. Among the genes reported by PCA-based unsupervised feature extraction, we propose that chemokine signaling pathways and leucine rich repeat proteins are key factors that initiate transgenerational epigenetic-mediated diseases, because multiple genes included in these two categories were identified in this study.

  17. Defects in intracellular trafficking of fungal cell wall synthases lead to aberrant host immune recognition.

    PubMed

    Esher, Shannon K; Ost, Kyla S; Kohlbrenner, Maria A; Pianalto, Kaila M; Telzrow, Calla L; Campuzano, Althea; Nichols, Connie B; Munro, Carol; Wormley, Floyd L; Alspaugh, J Andrew

    2018-06-01

    The human fungal pathogen, Cryptococcus neoformans, dramatically alters its cell wall, both in size and composition, upon entering the host. This cell wall remodeling is essential for host immune avoidance by this pathogen. In a genetic screen for mutants with changes in their cell wall, we identified a novel protein, Mar1, that controls cell wall organization and immune evasion. Through phenotypic studies of a loss-of-function strain, we have demonstrated that the mar1Δ mutant has an aberrant cell surface and a defect in polysaccharide capsule attachment, resulting in attenuated virulence. Furthermore, the mar1Δ mutant displays increased staining for exposed cell wall chitin and chitosan when the cells are grown in host-like tissue culture conditions. However, HPLC analysis of whole cell walls and RT-PCR analysis of cell wall synthase genes demonstrated that this increased chitin exposure is likely due to decreased levels of glucans and mannans in the outer cell wall layers. We observed that the Mar1 protein differentially localizes to cellular membranes in a condition dependent manner, and we have further shown that the mar1Δ mutant displays defects in intracellular trafficking, resulting in a mislocalization of the β-glucan synthase catalytic subunit, Fks1. These cell surface changes influence the host-pathogen interaction, resulting in increased macrophage activation to microbial challenge in vitro. We established that several host innate immune signaling proteins are required for the observed macrophage activation, including the Card9 and MyD88 adaptor proteins, as well as the Dectin-1 and TLR2 pattern recognition receptors. These studies explore novel mechanisms by which a microbial pathogen regulates its cell surface in response to the host, as well as how dysregulation of this adaptive response leads to defective immune avoidance.

  18. Mobile phone radiation alters proliferation of hepatocarcinoma cells.

    PubMed

    Ozgur, Elcin; Guler, Goknur; Kismali, Gorkem; Seyhan, Nesrin

    2014-11-01

    This study investigated the effects of intermittent exposure (15 min on, 15 min off for 1, 2, 3, or 4 h, at a specific absorption rate of 2 W/kg) to enhanced data rates for global system for mobile communication evolution-modulated radiofrequency radiation (RFR) at 900- and 1,800-MHz frequencies on the viability of the Hepatocarcinoma cells (Hep G2). Hep G2 cell proliferation was measured by a colorimetric assay based on the cleavage of the tetrazolium salt WST-1 by mitochondrial dehydrogenases in viable cells. Cell injury was evaluated by analyzing the levels of lactate dehydrogenase (LDH) and glucose released from lysed cells into the culture medium. Morphological observation of the nuclei was carried out by 4',6-diamidino-2-phenylindole (DAPI) staining using fluorescence microscopy. In addition, TUNEL assay was performed to confirm apoptotic cell death. It was observed that cell viability, correlated with the LDH and glucose levels, changed according to the frequency and duration of RFR exposure. Four-hour exposure produced more pronounced effects than the other exposure durations. 1,800-MHz RFR had a larger impact on cell viability and Hep G2 injury than the RFR at 900 MHz. Morphological observations also supported the biochemical results indicating that most of the cells showed irregular nuclei pattern determined by using the DAPI staining, as well as TUNEL assay which shows DNA damage especially in the cells after 4 h of exposure to 1,800-MHz RFR. Our results indicate that the applications of 900- and 1,800-MHz (2 W/kg) RFR cause to decrease in the proliferation of the Hep G2 cells after 4 h of exposure. Further studies will be conducted on other frequency bands of RFR and longer duration of exposure.

  19. Monitoring Cell Proliferation by Dye Dilution: Considerations for Probe Selection

    PubMed Central

    Tario, Joseph D.; Conway, Alexis N.; Muirhead, Katharine A.; Wallace, Paul K.

    2018-01-01

    In the third edition of this series, we described protocols for labeling cell populations with tracking dyes, and addressed issues to be considered when combining two different tracking dyes with other phenotypic and viability probes for the assessment of cytotoxic effector activity and regulatory T cell functions. We summarized key characteristics of and differences between general protein and membrane labeling dyes, discussed determination of optimal staining concentrations, and provided detailed labeling protocols for both dye types. Examples of the advantages of two color cell tracking were provided in the form of protocols for: (a) independent enumeration of viable effector and target cells in a direct cytotoxicity assay; and (b) an in vitro suppression assay for simultaneous proliferation monitoring of effector and regulatory T cells. The number of commercially available fluorescent cell tracking dyes has expanded significantly since the last edition, with new suppliers and/or new spectral properties being added at least annually. In this fourth edition, we describe evaluations to be performed by the supplier and/or user when characterizing a new cell tracking dye and by the user when selecting one for use in multicolor proliferation monitoring. These include methods for: Assessment of the dye’s spectral profile on the laboratory’s flow cytometer(s) to optimize compatibility with other employed fluorochromes and minimize compensation problems;Evaluating the effect of labeling on cell growth rate;Testing the fidelity with which dye dilution reports cell division;Determining the maximum number of generations to be included when using dye dilution profiles to estimate fold population expansion or frequency of responder cells; andVerifying that relevant cell functions (e.g., effector activity) remain unaltered by tracking dye labeling. PMID:29071683

  20. SerpinB1 Promotes Pancreatic β Cell Proliferation

    SciTech Connect

    El Ouaamari, Abdelfattah; Dirice, Ercument; Gedeon, Nicholas

    2016-01-01

    Compensatory β-cell growth in response to insulin resistance is a common feature in diabetes. We recently reported that liver-derived factors participate in this compensatory response in the liver insulin receptor knockout (LIRKO) mouse, a model of significant islet hyperplasia. Here we show that serpinB1 is a liver-derived secretory protein that controls β-cell proliferation. SerpinB1 is abundant in the hepatocyte secretome and sera derived from LIRKO mice. SerpinB1 and small molecule compounds that partially mimic serpinB1 activity enhanced proliferation of zebrafish, mouse and human β-cells. We report that serpinB1-induced β-cell replication requires protease inhibition activity and mice lacking serpinB1 exhibit attenuatedmore » β-cell replication in response to insulin resistance. Finally, SerpinB1-treatment of islets modulated signaling proteins in growth and survival pathways such as MAPK, PKA and GSK3. Together, these data implicate SerpinB1 as a protein that can potentially be harnessed to enhance functional β-cell mass in patients with diabetes.« less

  1. Effects of drinking desalinated seawater on cell viability and proliferation.

    PubMed

    Macarrão, Camila Longhi; Bachi, André Luis Lacerda; Mariano, Mario; Abel, Lucia Jamli

    2017-06-01

    Desalination of seawater is becoming an important means to address the increasing scarcity of freshwater resources in the world. Seawater has been used as drinking water in the health, food, and medical fields and various beneficial effects have been suggested, although not confirmed. Given the presence of 63 minerals and trace elements in drinking desalinated seawater (63 DSW), we evaluated their effects on the behavior of tumorigenic and nontumorigenic cells through the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and annexin-V-fluorescein isothiocyanate/propidium iodide staining. Our results showed that cell viability and proliferation in the presence of 63 DSW were significantly greater than in mineral water and in the presence of fetal bovine serum in a dose-dependent manner. Furthermore, 63 DSW showed no toxic effect on murine embryonic fibroblast (NIH-3T3) and murine melanoma (B16-F10) cells. In another assay, we also showed that pre-treatment of non-adherent THP-1 cells with 63 DSW reduces apoptosis incidence, suggesting a protective effect against cell death. We conclude that cell viability and proliferation were improved by the mineral components of 63 DSW and this effect can guide further studies on health effects associated with DSW consumption.

  2. 17betaE2 promotes cell proliferation in endometriosis by decreasing PTEN via NFkappaB-dependent pathway.

    PubMed

    Zhang, Hui; Zhao, Xingbo; Liu, Shu; Li, Jijun; Wen, Zeqing; Li, Mingjiang

    2010-04-12

    The objective of this study was to explore the mechanism of phosphatase and tensin homolog (PTEN) loss in endometriosis. We found that aberrant PTEN expression and mitogen-activated protein kinases (MAPK)/ERK, phosphoinositide 3-kinase (PI3K)/AKt, and nuclear factor-kappaB (NFkappaB) signaling overactivities coexisted in endometriosis. In vitro, 17beta-estradiol rapidly activated the 3 pathways in endometriotic cells and specific inhibitions on the 3 pathways respectively blocked 17beta-estradiol-induced cell proliferation. 17beta-estradiol suppressed PTEN transcription and expression in endometriotic cells which was abolished by specific NFkappaB inhibition. Total/nuclear PTEN-loss and MAPK/ERK, PI3K/AKt, and NFkappaB signal overactivities coexist in endometriosis. In vitro, 17beta-estradiol can promotes cell proliferation in endometriosis by activating PI3K/AKt pathway via an NFkappaB/PTEN-dependent pathway. For the first time we propose the possibility of the presence of a positive feedback-loop: 17beta-estradiol-->high NFkappaB-->low PTEN-->high PI3K-->high NFkappaB, in endometriosis, which may finally promote the proliferation of ectopic endometrial epithelial cells and in turn contributes to the progression of the disease.

  3. Illegitimate WNT signaling promotes proliferation of multiple myeloma cells

    PubMed Central

    Derksen, Patrick W. B.; Tjin, Esther; Meijer, Helen P.; Klok, Melanie D.; Mac Gillavry, Harold D.; van Oers, Marinus H. J.; Lokhorst, Henk M.; Bloem, Andries C.; Clevers, Hans; Nusse, Roel; van der Neut, Ronald; Spaargaren, Marcel; Pals, Steven T.

    2004-01-01

    The unrestrained growth of tumor cells is generally attributed to mutations in essential growth control genes, but tumor cells are also influenced by signals from the environment. In multiple myeloma (MM), the factors and signals coming from the bone marrow microenvironment are possibly even essential for the growth of the tumor cells. As targets for intervention, these signals may be equally important as mutated oncogenes. Given their oncogenic potential, WNT signals form a class of paracrine growth factors that could act to influence MM cell growth. In this paper, we report that MM cells have hallmarks of active WNT signaling, whereas the cells have not undergone detectable mutations in WNT signaling genes such as adenomatous polyposis coli and β-catenin (CTNNB1). We show that the malignant MM plasma cells overexpress β-catenin, including its N-terminally unphosphorylated form, suggesting active β-catenin/T cell factor-mediated transcription. Further accumulation and nuclear localization of β-catenin, and/or increased cell proliferation, was achieved by stimulation of WNT signaling with either Wnt3a, LiCl, or the constitutively active S33Y mutant of β-catenin. In contrast, by blocking WNT signaling by dominant-negative T cell factor, we can interfere with the growth of MM cells. We therefore suggest that MM cells are dependent on an active WNT signal, which may have important implications for the management of this incurable form of cancer. PMID:15067127

  4. Local cellular neighborhood controls proliferation in cell competition

    PubMed Central

    Bove, Anna; Gradeci, Daniel; Fujita, Yasuyuki; Banerjee, Shiladitya; Charras, Guillaume; Lowe, Alan R.

    2017-01-01

    Cell competition is a quality-control mechanism through which tissues eliminate unfit cells. Cell competition can result from short-range biochemical inductions or long-range mechanical cues. However, little is known about how cell-scale interactions give rise to population shifts in tissues, due to the lack of experimental and computational tools to efficiently characterize interactions at the single-cell level. Here, we address these challenges by combining long-term automated microscopy with deep-learning image analysis to decipher how single-cell behavior determines tissue makeup during competition. Using our high-throughput analysis pipeline, we show that competitive interactions between MDCK wild-type cells and cells depleted of the polarity protein scribble are governed by differential sensitivity to local density and the cell type of each cell’s neighbors. We find that local density has a dramatic effect on the rate of division and apoptosis under competitive conditions. Strikingly, our analysis reveals that proliferation of the winner cells is up-regulated in neighborhoods mostly populated by loser cells. These data suggest that tissue-scale population shifts are strongly affected by cellular-scale tissue organization. We present a quantitative mathematical model that demonstrates the effect of neighbor cell–type dependence of apoptosis and division in determining the fitness of competing cell lines. PMID:28931601

  5. Cell cycle inhibitor, p19INK4d, promotes cell survival and decreases chromosomal aberrations after genotoxic insult due to enhanced DNA repair.

    PubMed

    Scassa, María E; Marazita, Mariela C; Ceruti, Julieta M; Carcagno, Abel L; Sirkin, Pablo F; González-Cid, Marcela; Pignataro, Omar P; Cánepa, Eduardo T

    2007-05-01

    Genome integrity and cell proliferation and survival are regulated by an intricate network of pathways that includes cell cycle checkpoints, DNA repair and recombination, and programmed cell death. It makes sense that there should be a coordinated regulation of these different processes, but the components of such mechanisms remain unknown. In this report, we demonstrate that p19INK4d expression enhances cell survival under genotoxic conditions. By using p19INK4d-overexpressing clones, we demonstrated that p19INK4d expression correlates with the cellular resistance to UV treatment with increased DNA repair activity against UV-induced lesions. On the contrary, cells transfected with p19INK4d antisense cDNA show reduced ability to repair DNA damage and increased sensitivity to genotoxic insult when compared with their p19INK4d-overexpressing counterparts. Consistent with these findings, our studies also show that p19INK4d-overexpressing cells present not only a minor accumulation of UV-induced chromosomal aberrations but a lower frequency of spontaneous chromosome abnormalities than p19INK4d-antisense cells. Lastly, we suggest that p19INK4d effects are dissociated from its role as CDK4/6 inhibitor. The results presented herein support a crucial role for p19INK4d in regulating genomic stability and overall cell viability under conditions of genotoxic stress. We propose that p19INK4d would belong to a protein network that would integrate DNA repair, apoptotic and checkpoint mechanisms in order to maintain the genomic integrity.

  6. Artemisinin reduces cell proliferation and induces apoptosis in neuroblastoma.

    PubMed

    Zhu, Shunqin; Liu, Wanhong; Ke, Xiaoxue; Li, Jifu; Hu, Renjian; Cui, Hongjuan; Song, Guanbin

    2014-09-01

    Artemisinin, a natural product from the Chinese medicinal plant, Artemisia annua L., is commonly used in the treatment of malaria, and has recently been reported to have potent anticancer activity in various types of human tumors. Yet, the effect of artemisinin on neuroblastoma is still unclear. In the present study, we aimed to investigate the effects of artemisinin on neuroblastoma cells. We observed that artemisinin significantly inhibited cell growth and proliferation, and caused cell cycle arrest in the G1 phase in neuroblastoma cell lines. Annexin V-FITC/PI staining assay revealed that artemisinin markedly induced apoptosis. Soft agar assays revealed that artemisinin suppressed the ability of clonogenic formation of neuroblastoma cells and a xenograft study in NOD/SCID mice showed that artemisinin inhibited tumor growth and development in vivo. Therefore, our results suggest that the Chinese medicine artemisinin could serve as a novel potential therapeutic agent in the treatment of neuroblastoma.

  7. Inosine Released from Dying or Dead Cells Stimulates Cell Proliferation via Adenosine Receptors.

    PubMed

    Chen, Jin; Chaurio, Ricardo A; Maueröder, Christian; Derer, Anja; Rauh, Manfred; Kost, Andriy; Liu, Yi; Mo, Xianming; Hueber, Axel; Bilyy, Rostyslav; Herrmann, Martin; Zhao, Yi; Muñoz, Luis E

    2017-01-01

    Many antitumor therapies induce apoptotic cell death in order to cause tumor regression. Paradoxically, apoptotic cells are also known to promote wound healing, cell proliferation, and tumor cell repopulation in multicellular organisms. We aimed to characterize the nature of the regenerative signals concentrated in the micromilieu of dead and dying cells. Cultures of viable melanoma B16F10 cells, mouse fibroblasts, and primary human fibroblast-like synoviocytes (FLS) in the presence of dead and dying cells, their supernatants (SNs), or purified agonists and antagonists were used to evaluate the stimulation of proliferation. Viable cell quantification was performed by either flow cytometry of harvested cells or by crystal violet staining of adherent cells. High-performance liquid chromatography and liquid chromatography coupled with mass spectrometry of cell SNs were deployed to identify the nature of growth-promoting factors. Coimplantation of living cells in the presence of SNs collected from dead and dying cells and specific agonists was used to evaluate tumor growth in vivo . The stimulation of proliferation of few surviving cells by bystander dead cells was confirmed for melanoma cells, mouse fibroblasts, and primary FLS. We found that small soluble molecules present in the protein-free fraction of SNs of dead and dying cells were responsible for the promotion of proliferation. The nucleoside inosine released by dead and dying cells acting via adenosine receptors was identified as putative inducer of proliferation of surviving tumor cells after irradiation and heat treatment. Inosine released by dead and dying cells mediates tumor cell proliferation via purinergic receptors. Therapeutic strategies surmounting this pathway may help to reduce the rate of recurrence after radio- and chemotherapy.

  8. CD98 regulates vascular smooth muscle cell proliferation in atherosclerosis.

    PubMed

    Baumer, Yvonne; McCurdy, Sara; Alcala, Martin; Mehta, Nehal; Lee, Bog-Hieu; Ginsberg, Mark H; Boisvert, William A

    2017-01-01

    Vascular smooth muscle cells (VSMC) migrate and proliferate to form a stabilizing fibrous cap that encapsulates atherosclerotic plaques. CD98 is a transmembrane protein made of two subunits, CD98 heavy chain (CD98hc) and one of six light chains, and is known to be involved in cell proliferation and survival. Because the influence of CD98hc on atherosclerosis development is unknown, our aim was to determine if CD98hc expressed on VSMC plays a role in shaping the morphology of atherosclerotic plaques by regulating VSMC function. In addition to determining the role of CD98hc in VSMC proliferation and apoptosis, we utilized mice with SMC-specific deletion of CD98hc (CD98hc fl/fl SM22αCre + ) to determine the effects of CD98hc deficiency on VSMC function in atherosclerotic plaque. After culturing for 5 days in vitro, CD98hc -/- VSMC displayed dramatically reduced cell counts, reduced proliferation, as well as reduced migration compared to control VSMC. Analysis of aortic VSCM after 8 weeks of HFD showed a reduction in CD98hc -/- VSMC proliferation as well as increased apoptosis compared to controls. A long-term atherosclerosis study using SMC-CD98hc -/- /ldlr -/- mice was performed. Although total plaque area was unchanged, CD98hc -/- mice showed reduced presence of VSMC within the plaque (2.1 ± 0.4% vs. 4.3 ± 0.4% SM22α-positive area per plaque area, p < 0.05), decreased collagen content, as well as increased necrotic core area (25.8 ± 1.9% vs. 10.9 ± 1.6%, p < 0.05) compared to control ldlr -/- mice. We conclude that CD98hc is required for VSMC proliferation, and that its deficiency leads to significantly reduced presence of VSMC in the neointima. Thus, CD98hc expression in VSMC contributes to the formation of plaques that are morphologically more stable, and thereby protects against atherothrombosis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  9. MET signalling in primary colon epithelial cells leads to increased transformation irrespective of aberrant Wnt signalling

    PubMed Central

    Boon, E M J; Kovarikova, M; Derksen, P W B; van der Neut, R

    2005-01-01

    It has been shown that in hereditary and most sporadic colon tumours, components of the Wnt pathway are mutated. The Wnt target MET has been implicated in the development of colon cancer. Here, we show that overexpression of wild-type or a constitutively activated form of MET in colon epithelial cells leads to increased transformation irrespective of Wnt signalling. Fetal human colon epithelial cells without aberrant Wnt signalling were transfected with wild-type or mutated MET constructs. Expression of these constructs leads to increased phosphorylation of MET and its downstream targets PKB and MAPK. Upon stimulation with HGF, the expression of E-cadherin is downregulated in wild-type MET-transfected cells, whereas cells expressing mutated MET show low E-cadherin levels independent of stimulation with ligand. This implies a higher migratory propensity of these cells. Furthermore, fetal human colon epithelial cells expressing the mutated form of MET have colony-forming capacity in soft agar, while cells expressing wild-type MET show an intermediate phenotype. Subcutaneous injection of mutated MET-transfected cells in nude mice leads to the formation of tumours within 12 days in all mice injected. At this time point, mock-transfected cells do not form tumours, while wild-type MET-transfected cells form subcutaneous tumours in one out of five mice. We thus show that MET signalling can lead to increased transformation of colon epithelial cells independent of Wnt signalling and in this way could play an essential role in the onset and progression of colorectal cancer. PMID:15785735

  10. Overexpression of the growth arrest-specific homeobox gene Gax inhibits proliferation, migration, cell cycle progression, and apoptosis in serum-induced vascular smooth muscle cells.

    PubMed

    Zheng, H; Xue, S; Hu, Z L; Shan, J G; Yang, W G

    2014-03-24

    The Gax gene has been implicated in a variety of cell-developmental and biological processes, and aberrant Gax expression is linked to many diseases. In this study, to provide important insights for Gax-based gene therapy in vein graft restenosis and its anti-restenotic mechanism, we used rabbit vascular smooth muscle cells (VSMCs) to investigate the effects of Gax overexpression on proliferation, migration, cell cycle, and apoptosis in a serum-stimulated culture. Rabbit VSMC lines that stably overexpressed Gax were established by transfection with recombinant adenoviral vector Ad5-Gax. The effect of Gax overexpression on in vitro serum-induced VSMCs proliferation, migration, cell cycle, and apoptosis was assessed by MTT, wound healing, and flow cytometry assays, respectively. To investigate the effect of Gax overexpression on PCNA and MMP-2 in serum-induced VSMCs, immunocytochemistry, RT-PCR, and gelatin zymography were performed. The results clearly showed that Gax overexpression decreases PCNA expression in serum-induced VSMCs. Gax overexpression also significantly inhibited cell proliferation by blocking entry into the S-phase of the cell cycle, promoted cell apoptosis, and reduced cell migration activity by downregulating MMP-2 release and activity. These findings indicate that Gax would be an optimal target gene for gene therapy to treat vein graft restenosis.

  11. Adiponectin as novel regulator of cell proliferation in human glioblastoma.

    PubMed

    Porcile, Carola; Di Zazzo, Erika; Monaco, Maria Ludovica; D'Angelo, Giorgia; Passarella, Daniela; Russo, Claudio; Di Costanzo, Alfonso; Pattarozzi, Alessandra; Gatti, Monica; Bajetto, Adriana; Zona, Gianluigi; Barbieri, Federica; Oriani, Giovannangelo; Moncharmont, Bruno; Florio, Tullio; Daniele, Aurora

    2014-10-01

    Adiponectin (Acrp30) is an adipocyte-secreted hormone with pleiotropic metabolic effects, whose reduced levels were related to development and progression of several malignancies. We looked at the presence of Acrp30 receptors in human glioblastomas (GBM), hypothesizing a role for Acrp30 also in this untreatable cancer. Here we demonstrate that human GBM express Acrp30 receptors (AdipoR1 and AdipoR2), which are often co-expressed in GBM samples (70% of the analyzed tumors). To investigate the effects of Acrp30 on GBM growth, we used human GBM cell lines U87-MG and U251, expressing both AdipoR1 and AdipoR2 receptors. In these cells, Acrp30 treatment inhibits DNA synthesis and cell proliferation rate, inducing arrest in G1 phase of the cell cycle. These effects were correlated to a sustained activation of ERK1/2 and Akt kinases, upon Acrp30 treatment. Our results suggest that Acrp30 may represent a novel endogenous negative regulator of GBM cell proliferation, to be evaluated for the possible development of novel pharmacological approaches. © 2014 Wiley Periodicals, Inc.

  12. 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

  13. 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.

  14. Infection and Proliferation of Giant Viruses in Amoeba Cells.

    PubMed

    Takemura, Masaharu

    2016-01-01

    Acanthamoeba polyphaga mimivirus, the first discovered giant virus with genome size and particle size much larger than previously discovered viruses, possesses several genes for translation and CRISPER Cas system-like defense mechanism against virophages, which co-infect amoeba cells with the giant virus and which inhibit giant virus proliferation. Mimiviruses infect amoeba cells by phagocytosis and release their DNA into amoeba cytoplasm through their stargate structure. After infection, giant virion factories (VFs) form in amoeba cytoplasm, followed by DNA replication and particle formation at peripheral regions of VF. Marseilleviruses, the smallest giant viruses, infect amoeba cells by phagocytosis or endocytosis, form larger VF than Mimivirus's VF in amoeba cytoplasm, and replicate their particles. Pandoraviruses found in 2013 have the largest genome size and particle size among all viruses ever found. Pandoraviruses infect amoeba cells by phagocytosis and release their DNA into amoeba cytoplasm through their mouth-like apical pores. The proliferation of Pandoraviruses occurs along with nucleus disruption. New virions form at the periphery of the region formerly occupied by the amoeba cell nucleus.

  15. Nonprenylated Xanthones from Gentiana lutea, Frasera caroliniensis, and Centaurium erythraea as Novel Inhibitors of Vascular Smooth Muscle Cell Proliferation.

    PubMed

    Waltenberger, Birgit; Liu, Rongxia; Atanasov, Atanas G; Schwaiger, Stefan; Heiss, Elke H; Dirsch, Verena M; Stuppner, Hermann

    2015-11-13

    Aberrant proliferation of vascular smooth muscle cells (VSMC) plays a major role in restenosis, the pathological renarrowing of the blood vessel lumen after surgical treatment of stenosis. Since available anti-proliferative pharmaceuticals produce unfavorable side effects, there is high demand for the identification of novel VSMC proliferation inhibitors. A natural product screening approach using a resazurin conversion assay enabled the identification of gentisin (1) from Gentiana lutea as a novel inhibitor of VSMC proliferation with an IC50 value of 7.84 µM. Aiming to identify further anti-proliferative compounds, 13 additional nonprenylated xanthones, isolated from different plant species, were also tested. While some compounds showed no or moderate activity at 30 µM, 1-hydroxy-2,3,4,5-tetramethoxyxanthone (4), swerchirin (6), and methylswertianin (7) showed IC50 values between 10.2 and 12.5 µM. The anti-proliferative effect of 1, 4, 6, and 7 was confirmed by the quantification of DNA synthesis (BrdU incorporation) in VSMC. Cell death quantification (determined by LDH release in the culture medium) revealed that the compounds are not cytotoxic in the investigated concentration range. In conclusion, nonprenylated xanthones are identified as novel, non-toxic VSMC proliferation inhibitors, which might contribute to the development of new therapeutic applications to combat restenosis.

  16. TORC1 is required to balance cell proliferation and cell death in planarians

    PubMed Central

    Tu, Kimberly C.; Pearson, Bret J.; Alvarado, Alejandro Sánchez

    2012-01-01

    Multicellular organisms are equipped with cellular mechanisms that enable them to replace differentiated cells lost to normal physiological turnover, injury, and for some such as planarians, even amputation. This process of tissue homeostasis is generally mediated by adult stem cells (ASCs), tissue-specific stem cells responsible for maintaining anatomical form and function. To do so, ASCs must modulate the balance between cell proliferation, i.e. in response to nutrients, and that of cell death, i.e. in response to starvation or injury. But how these two antagonistic processes are coordinated remains unclear. Here, we explore the role of the core components of the TOR pathway during planarian tissue homeostasis and regeneration and identified an essential function for TORC1 in these two processes. RNAi-mediated silencing of TOR in intact animals resulted in a significant increase in cell death, whereas stem cell proliferation and stem cell maintenance were unaffected. Amputated animals failed to increase stem cell proliferation after wounding and displayed defects in tissue remodeling. Together, our findings suggest two distinct roles for TORC1 in planarians. TORC1 is required to modulate the balance between cell proliferation and cell death during normal cell turnover and in response to nutrients. In addition, it is required to initiate appropriate stem cell proliferation during regeneration and for proper tissue remodeling to occur to maintain scale and proportion. PMID:22445864

  17. Interpreting Chromosome Aberration Spectra

    NASA Technical Reports Server (NTRS)

    Levy, Dan; Reeder, Christopher; Loucas, Bradford; Hlatky, Lynn; Chen, Allen; Cornforth, Michael; Sachs, Rainer

    2007-01-01

    Ionizing radiation can damage cells by breaking both strands of DNA in multiple locations, essentially cutting chromosomes into pieces. The cell has enzymatic mechanisms to repair such breaks; however, these mechanisms are imperfect and, in an exchange process, may produce a large-scale rearrangement of the genome, called a chromosome aberration. Chromosome aberrations are important in killing cells, during carcinogenesis, in characterizing repair/misrepair pathways, in retrospective radiation biodosimetry, and in a number of other ways. DNA staining techniques such as mFISH ( multicolor fluorescent in situ hybridization) provide a means for analyzing aberration spectra by examining observed final patterns. Unfortunately, an mFISH observed final pattern often does not uniquely determine the underlying exchange process. Further, resolution limitations in the painting protocol sometimes lead to apparently incomplete final patterns. We here describe an algorithm for systematically finding exchange processes consistent with any observed final pattern. This algorithm uses aberration multigraphs, a mathematical formalism that links the various aspects of aberration formation. By applying a measure to the space of consistent multigraphs, we will show how to generate model-specific distributions of aberration processes from mFISH experimental data. The approach is implemented by software freely available over the internet. As a sample application, we apply these algorithms to an aberration data set, obtaining a distribution of exchange cycle sizes, which serves to measure aberration complexity. Estimating complexity, in turn, helps indicate how damaging the aberrations are and may facilitate identification of radiation type in retrospective biodosimetry.

  18. Interstitial telomeric repeats are not preferentially involved in radiation-induced chromosome aberrations in human cells.

    PubMed

    Desmaze, C; Pirzio, L M; Blaise, R; Mondello, C; Giulotto, E; Murnane, J P; Sabatier, L

    2004-01-01

    Telomeric repeat sequences, located at the end of eukaryotic chromosomes, have been detected at intrachromosomal locations in many species. Large blocks of telomeric sequences are located near the centromeres in hamster cells, and have been reported to break spontaneously or after exposure to ionizing radiation, leading to chromosome aberrations. In human cells, interstitial telomeric sequences (ITS) can be composed of short tracts of telomeric repeats (less than twenty), or of longer stretches of exact and degenerated hexanucleotides, mainly localized at subtelomeres. In this paper, we analyzed the radiation sensitivity of a naturally occurring short ITS localized in 2q31 and we found that this region is not a hot spot of radiation-induced chromosome breaks. We then selected a human cell line in which approximately 800 bp of telomeric DNA had been introduced by transfection into an internal euchromatic chromosomal region in chromosome 4q. In parallel, a cell line containing the plasmid without telomeric sequences was also analyzed. Both regions containing the transfected plasmids showed a higher frequency of radiation-induced breaks than expected, indicating that the instability of the regions containing the transfected sequences is not due to the presence of telomeric sequences. Taken together, our data show that ITS themselves do not enhance the formation of radiation-induced chromosome rearrangements in these human cell lines. Copyright 2003 S. Karger AG, Basel

  19. Cells Comprising the Prostate Cancer Microenvironment Lack Recurrent Clonal Somatic Genomic Aberrations

    PubMed Central

    Bianchi-Frias, Daniella; Basom, Ryan; Delrow, Jeffrey J; Coleman, Ilsa M; Dakhova, Olga; Qu, Xiaoyu; Fang, Min; Franco, Omar E.; Ericson, Nolan G.; Bielas, Jason H.; Hayward, Simon W.; True, Lawrence; Morrissey, Colm; Brown, Lisha; Bhowmick, Neil A.; Rowley, David; Ittmann, Michael; Nelson, Peter S.

    2017-01-01

    Prostate cancer-associated stroma (CAS) plays an active role in malignant transformation, tumor progression, and metastasis. Molecular analyses of CAS have demonstrated significant changes in gene expression; however, conflicting evidence exists on whether genomic alterations in benign cells comprising the tumor microenvironment (TME) underlie gene expression changes and oncogenic phenotypes. This study evaluates the nuclear and mitochondrial DNA integrity of prostate carcinoma cells, CAS, matched benign epithelium and benign epithelium-associated stroma by whole genome copy number analyses, targeted sequencing of TP53, and fluorescence in situ hybridization. Comparative genomic hybridization (aCGH) of CAS revealed a copy-neutral diploid genome with only rare and small somatic copy number aberrations (SCNAs). In contrast, several expected recurrent SCNAs were evident in the adjacent prostate carcinoma cells, including gains at 3q, 7p, and 8q, and losses at 8p and 10q. No somatic TP53 mutations were observed in CAS. Mitochondrial DNA (mtDNA) extracted from carcinoma cells and stroma identified 23 somatic mtDNA mutations in neoplastic epithelial cells but only one mutation in stroma. Finally, genomic analyses identified no SCNAs, no loss of heterozygosity (LOH) or copy-neutral LOH in cultured cancer-associated fibroblasts (CAFs), which are known to promote prostate cancer progression in vivo. PMID:26753621

  20. Supra-physiological folic acid concentrations induce aberrant DNA methylation in normal human cells in vitro.

    PubMed

    Charles, Michelle A; Johnson, Ian T; Belshaw, Nigel J

    2012-07-01

    The micronutrients folate and selenium may modulate DNA methylation patterns by affecting intracellular levels of the methyl donor S-adenosylmethionine (SAM) and/or the product of methylation reactions S-adenosylhomocysteine (SAH). WI-38 fibroblasts and FHC colon epithelial cells were cultured in the presence of two forms of folate or four forms of selenium at physiologically-relevant doses, and their effects on LINE-1 methylation, gene-specific CpG island (CGI) methylation and intracellular SAM:SAH were determined. At physiologically-relevant doses the forms of folate or selenium had no effect on LINE-1 or CGI methylation, nor on intracellular SAM:SAH. However the commercial cell culture media used for the selenium studies, containing supra-physiological concentrations of folic acid, induced LINE-1 hypomethylation, CGI hypermethylation and decreased intracellular SAM:SAH in both cell lines. We conclude that the exposure of normal human cells to supra-physiological folic acid concentrations present in commercial cell culture media perturbs the intracellular SAM:SAH ratio and induces aberrant DNA methylation.

  1. 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

  2. Induced chromosomal aberrations in somatic cells of Nigella sativa L. by mitomycin C.

    PubMed

    Kumar, P; Nizam, J

    1978-01-01

    A cytological study was carried out on root tips of Nigella sativa L. by treatment with Mitomycin C at 0.001% for six time intervals (10, 15, 20, 30, 40, and 50 min). The chromosomal abnormalities were increasingly proportionate to the increase in time of treatment. The seedlings treated with a 0.001% concentration of Mitomycin C for 10 min. did not show any significant effect. At other time intervals, the effect was observed to be quite significant. Beyond 40 min. treatment almost all the cells would become sticky. Thirty minutes' treatment showed significant effect, inducing various types of chromosomal aberrations in the anaphase, such as bridges and fragments of 34.13% and 48.07%, respectively.

  3. An Antagonistic Vascular Endothelial Growth Factor (VEGF) Variant Inhibits VEGF-Stimulated Receptor Autophosphorylation and Proliferation of Human Endothelial Cells

    NASA Astrophysics Data System (ADS)

    Siemeister, Gerhard; Schirner, Michael; Reusch, Petra; Barleon, Bernhard; Marme, Dieter; Martiny-Baron, Georg

    1998-04-01

    Vascular endothelial growth factor (VEGF) is a potent mitogen with a unique specificity for endothelial cells and a key mediator of aberrant endothelial cell proliferation and vascular permeability in a variety of human pathological situations, such as tumor angiogenesis, diabetic retinopathy, rheumatoid arthritis, or psoriasis. VEGF is a symmetric homodimeric molecule with two receptor binding interfaces lying on each pole of the molecule. Herein we report on the construction and recombinant expression of an asymmetric heterodimeric VEGF variant with an intact receptor binding interface at one pole and a mutant receptor binding interface at the second pole of the dimer. This VEGF variant binds to VEGF receptors but fails to induce receptor activation. In competition experiments, the heterodimeric VEGF variant antagonizes VEGF-stimulated receptor autophosphorylation and proliferation of endothelial cells. A 15-fold excess of the heterodimer was sufficient to inhibit VEGF-stimulated endothelial cell proliferation by 50%, and a 100-fold excess resulted in an almost complete inhibition. By using a rational approach that is based on the structure of VEGF, we have shown the feasibility to construct a VEGF variant that acts as an VEGF antagonist.

  4. NF-YB Regulates Spermatogonial Stem Cell Self-Renewal and Proliferation in the Planarian Schmidtea mediterranea.

    PubMed

    Iyer, Harini; Collins, James J; Newmark, Phillip A

    2016-06-01

    Gametes are the source and carrier of genetic information, essential for the propagation of all sexually reproducing organisms. Male gametes are derived from a progenitor stem cell population called spermatogonial stem cells (SSCs). SSCs give rise to male gametes through the coordination of two essential processes: self-renewal to produce more SSCs, and differentiation to produce mature sperm. Disruption of this equilibrium can lead to excessive proliferation of SSCs, causing tumorigenesis, or can result in aberrant differentiation, leading to infertility. Little is known about how SSCs achieve the fine balance between self-renewal and differentiation, which is necessary for their remarkable output and developmental potential. To understand the mechanisms of SSC maintenance, we examine the planarian homolog of Nuclear Factor Y-B (NF-YB), which is required for the maintenance of early planarian male germ cells. Here, we demonstrate that NF-YB plays a role in the self-renewal and proliferation of planarian SSCs, but not in their specification or differentiation. Furthermore, we characterize members of the NF-Y complex in Schistosoma mansoni, a parasitic flatworm related to the free-living planarian. We find that the function of NF-YB in regulating male germ cell proliferation is conserved in schistosomes. This finding is especially significant because fecundity is the cause of pathogenesis of S. mansoni. Our findings can help elucidate the complex relationship between self-renewal and differentiation of SSCs, and may also have implications for understanding and controlling schistosomiasis.

  5. Cytotoxic effect of butein on human colon adenocarcinoma cell proliferation.

    PubMed

    Yit, C C; Das, N P

    1994-07-15

    Several classes of plant polyphenols namely, flavonoids, chalcones and coumarins exhibited varying degrees of inhibition on the cell proliferation of human colon adenocarcinoma cell line 220.1. At the highest concentration tested (100 microM), many of the chalcones showed > 100% growth inhibition and their order of potency was butein > 2'-hydroxychalcone > 2-hydroxychalcone > 2',6'-dihydroxy-4'-methoxychalcone > 2',4-dihydroxychalcone with IC50 values of 1.75, 6.2, 7.5, 17, 23 microM, respectively. Butein (the most potent chalcone) at 2 microM concentration inhibited the incorporation of 14C-labelled thymidine, uridine and leucine into the colon cancer cells whilst 5-fluorouracil (5-FU, a chemotherapeutic drug) at 50 microM concentration could significantly inhibit only the uridine incorporation. The mode of cytotoxic action of butein was different from 5-FU but may be similar to colchicine, a known HeLa cell inhibitor.

  6. Induction of Chromosomal Aberrations at Fluences of Less Than One HZE Particle per Cell Nucleus

    NASA Technical Reports Server (NTRS)

    Hada, Megumi; Chappell, Lori J.; Wang, Minli; George, Kerry A.; Cucinotta, Francis A.

    2014-01-01

    The assumption of a linear dose response used to describe the biological effects of high LET radiation is fundamental in radiation protection methodologies. We investigated the dose response for chromosomal aberrations for exposures corresponding to less than one particle traversal per cell nucleus by high energy and charge (HZE) nuclei. Human fibroblast and lymphocyte cells where irradiated with several low doses of <0.1 Gy, and several higher doses of up to 1 Gy with O (77 keV/ (long-s)m), Si (99 keV/ (long-s)m), Fe (175 keV/ (long-s)m), Fe (195 keV/ (long-s)m) or Fe (240 keV/ (long-s)m) particles. Chromosomal aberrations at first mitosis were scored using fluorescence in situ hybridization (FISH) with chromosome specific paints for chromosomes 1, 2 and 4 and DAPI staining of background chromosomes. Non-linear regression models were used to evaluate possible linear and non-linear dose response models based on these data. Dose responses for simple exchanges for human fibroblast irradiated under confluent culture conditions were best fit by non-linear models motivated by a non-targeted effect (NTE). Best fits for the dose response data for human lymphocytes irradiated in blood tubes were a NTE model for O and a linear response model fit best for Si and Fe particles. Additional evidence for NTE were found in low dose experiments measuring gamma-H2AX foci, a marker of double strand breaks (DSB), and split-dose experiments with human fibroblasts. Our results suggest that simple exchanges in normal human fibroblasts have an important NTE contribution at low particle fluence. The current and prior experimental studies provide important evidence against the linear dose response assumption used in radiation protection for HZE particles and other high LET radiation at the relevant range of low doses.

  7. Induction of chromosomal aberrations at fluences of less than one HZE particle per cell nucleus.

    PubMed

    Hada, Megumi; Chappell, Lori J; Wang, Minli; George, Kerry A; Cucinotta, Francis A

    2014-10-01

    The assumption of a linear dose response used to describe the biological effects of high-LET radiation is fundamental in radiation protection methodologies. We investigated the dose response for chromosomal aberrations for exposures corresponding to less than one particle traversal per cell nucleus by high-energy charged (HZE) nuclei. Human fibroblast and lymphocyte cells were irradiated with several low doses of <0.1 Gy, and several higher doses of up to 1 Gy with oxygen (77 keV/μm), silicon (99 keV/μm) or Fe (175 keV/μm), Fe (195 keV/μm) or Fe (240 keV/μm) particles. Chromosomal aberrations at first mitosis were scored using fluorescence in situ hybridization (FISH) with chromosome specific paints for chromosomes 1, 2 and 4 and DAPI staining of background chromosomes. Nonlinear regression models were used to evaluate possible linear and nonlinear dose-response models based on these data. Dose responses for simple exchanges for human fibroblasts irradiated under confluent culture conditions were best fit by nonlinear models motivated by a nontargeted effect (NTE). The best fits for dose response data for human lymphocytes irradiated in blood tubes were a linear response model for all particles. Our results suggest that simple exchanges in normal human fibroblasts have an important NTE contribution at low-particle fluence. The current and prior experimental studies provide important evidence against the linear dose response assumption used in radiation protection for HZE particles and other high-LET radiation at the relevant range of low doses.

  8. Lysyl oxidase propeptide inhibits smooth muscle cell signaling and proliferation

    SciTech Connect

    Hurtado, Paola A.; Vora, Siddharth; Sume, Siddika Selva

    2008-02-01

    Lysyl oxidase is required for the normal biosynthesis and maturation of collagen and elastin. It is expressed by vascular smooth muscle cells, and its increased expression has been previously found in atherosclerosis and in models of balloon angioplasty. The lysyl oxidase propeptide (LOX-PP) has more recently been found to have biological activity as a tumor suppressor, and it inhibits Erk1/2 Map kinase activation. We reasoned that LOX-PP may have functions in normal non-transformed cells. We, therefore, investigated its effects on smooth muscle cells, focusing on important biological processes mediated by Erk1/2-dependent signaling pathways including proliferation and matrix metalloproteinase-9 (MMP-9) expression.more » In addition, we investigated whether evidence for accumulation of LOX-PP could be found in vivo in a femoral artery injury model. Recombinant LOX-PP was expressed and purified, and was found to inhibit primary rat aorta smooth muscle cell proliferation and DNA synthesis by more than 50%. TNF-{alpha}-stimulated MMP-9 expression and Erk1/2 activation were both significantly inhibited by LOX-PP. Immunohistochemistry studies carried out with affinity purified anti-LOX-PP antibody showed that LOX-PP epitopes were expressed at elevated levels in vascular lesions of injured arteries. These novel data suggest that LOX-PP may provide a feedback control mechanism that serves to inhibit properties associated with the development of vascular pathology.« less

  9. Toll-like receptor signaling in cell proliferation and survival

    PubMed Central

    Li, Xinyan; Jiang, Song; Tapping, Richard I.

    2009-01-01

    Toll-like receptors (TLRs) are important sensors of foreign microbial components as well as products of damaged or inflamed self tissues. Upon sensing these molecules, TLRs initiate a series of downstream signaling events that drive cellular responses including the production of cytokines, chemokines and other inflammatory mediators. This outcome results from the intracellular assembly of protein complexes that drive phosphorylation and other signaling cascades ultimately leading to chromatin remodeling and transcription factor activation. In addition to driving inflammatory responses, TLRs also regulate cell proliferation and survival which serves to expand useful immune cells and integrate inflammatory responses and tissue repair processes. In this context, central TLR signaling molecules, such as the mitogen-activated protein kinases (MAPK) and phosphoinositide 3-kinase (PI3K), play key roles. In addition, four major groups of transcription factors which are targets of TLR activation also control cell fate. This review focuses on the role of TLR signaling as it relates to cell proliferation and survival. This topic not only has important implications for understanding host defense and tissue repair, but also cancer which is often associated with conditions of chronic inflammation. PMID:19775907

  10. Proliferation of human mammary cancer cells exposed to 27-hydroxycholesterol

    PubMed Central

    CRUZ, PAMELA; TORRES, CRISTIAN; RAMÍREZ, MARÍA EUGENIA; EPUÑÁN, MARÍA JOSÉ; VALLADARES, LUIS EMILIO; SIERRALTA, WALTER DANIEL

    2010-01-01

    The aim of the present study was to identify the possible mechanisms by which certain estradiol receptor (ER)-positive mammary tumor cells remain resistant to treatment with anti-estrogens or inhibitors of local estradiol (E2) production. To this end, we compared the proliferative effects on mammary cancer cells of the novel selective ER modulator 27-hydroxycholesterol (27OHC) to those of E2, and evaluated their inhibition by ICI 182,780 (ICI). Analysis of the effects on the cell cycle of 27OHC and E2 in the absence or presence of ICI was conducted. In ER-positive mammary tumor cells, we detected the blocking of 27OHC proliferation-stimulatory activity by simvastatin, as well as the inhibition of E2-stimulated proliferation by an α-fetoprotein-derived cyclic nonapeptide. The effects reported herein may be extrapolated to infiltrating mammary cancer, where the activity of local macrophages may stimulate tumor growth. We suggest that increased breast cancer growth in obese patients may be related to increased 27OHC circulatory levels. PMID:22993572

  11. Proliferation of human mammary cancer cells exposed to 27-hydroxycholesterol.

    PubMed

    Cruz, Pamela; Torres, Cristian; Ramírez, María Eugenia; Epuñán, María José; Valladares, Luis Emilio; Sierralta, Walter Daniel

    2010-05-01

    The aim of the present study was to identify the possible mechanisms by which certain estradiol receptor (ER)-positive mammary tumor cells remain resistant to treatment with anti-estrogens or inhibitors of local estradiol (E(2)) production. To this end, we compared the proliferative effects on mammary cancer cells of the novel selective ER modulator 27-hydroxycholesterol (27OHC) to those of E(2), and evaluated their inhibition by ICI 182,780 (ICI). Analysis of the effects on the cell cycle of 27OHC and E(2) in the absence or presence of ICI was conducted. In ER-positive mammary tumor cells, we detected the blocking of 27OHC proliferation-stimulatory activity by simvastatin, as well as the inhibition of E(2)-stimulated proliferation by an α-fetoprotein-derived cyclic nonapeptide. The effects reported herein may be extrapolated to infiltrating mammary cancer, where the activity of local macrophages may stimulate tumor growth. We suggest that increased breast cancer growth in obese patients may be related to increased 27OHC circulatory levels.

  12. Unremitting Cell Proliferation in the Secretory Phase of Eutopic Endometriosis

    PubMed Central

    Franco-Murillo, Yanira; Miranda-Rodríguez, José Antonio; Rendón-Huerta, Erika; Montaño, Luis F.; Cornejo, Gerardo Velázquez; Gómez, Lucila Poblano; Valdez-Morales, Francisco Javier; Gonzalez-Sanchez, Ignacio

    2014-01-01

    Objective: Endometriosis is linked to altered cell proliferation and stem cell markers c-kit/stem cell factor (SCF) in ectopic endometrium. Our aim was to investigate whether c-kit/SCF also plays a role in eutopic endometrium. Design: Eutopic endometrium obtained from 35 women with endometriosis and 25 fertile eumenorrheic women was analyzed for in situ expression of SCF/c-kit, Ki67, RAC-alpha serine/threonine-protein kinase (Akt), phosphorylated RAC-alpha serine/threonin-protein kinase (pAkt), Glycogen synthase kinase 3 beta (GSK3β), and phosphorylated glycogen synthase kinase 3 beta (pGSK3β), throughout the menstrual cycle. Results: Expression of Ki67 and SCF was higher in endometriosis than in control tissue (P < .05) and greater in secretory rather than proliferative (P < .01) endometrium in endometriosis. Expression of c-kit was also higher in endometriosis although similar in both phases. Expression of Akt and GSK3β was identical in all samples and cycle phases, whereas pAkt and pGSK3β, opposed to control tissue, remained overexpressed in the secretory phase in endometriosis. Conclusion: Unceasing cell proliferation in the secretory phase of eutopic endometriosis is linked to deregulation of c-kit/SCF-associated signaling pathways. PMID:25194152

  13. MRG15 Regulates Embryonic Development and Cell Proliferation

    PubMed Central

    Tominaga, Kaoru; Kirtane, Bhakti; Jackson, James G.; Ikeno, Yuji; Ikeda, Takayoshi; Hawks, Christina; Smith, James R.; Matzuk, Martin M.; Pereira-Smith, Olivia M.

    2005-01-01

    MRG15 is a highly conserved protein, and orthologs exist in organisms from yeast to humans. MRG15 associates with at least two nucleoprotein complexes that include histone acetyltransferases and/or histone deacetylases, suggesting it is involved in chromatin remodeling. To study the role of MRG15 in vivo, we generated knockout mice and determined that the phenotype is embryonic lethal, with embryos and the few stillborn pups exhibiting developmental delay. Immunohistochemical analysis indicates that apoptosis in Mrg15−/− embryos is not increased compared with wild-type littermates. However, the number of proliferating cells is significantly reduced in various tissues of the smaller null embryos compared with control littermates. Cell proliferation defects are also observed in Mrg15−/− mouse embryonic fibroblasts. The hearts of the Mrg15−/− embryos exhibit some features of hypertrophic cardiomyopathy. The increase in size of the cardiomyocytes is most likely a response to decreased growth of the cells. Mrg15−/− embryos appeared pale, and microarray analysis revealed that α-globin gene expression was decreased in null versus wild-type embryos. We determined by chromatin immunoprecipitation that MRG15 was recruited to the α-globin promoter during dimethyl sulfoxide-induced mouse erythroleukemia cell differentiation. These findings demonstrate that MRG15 has an essential role in embryonic development via chromatin remodeling and transcriptional regulation. PMID:15798182

  14. Upregulation of LYAR induces neuroblastoma cell proliferation and survival.

    PubMed

    Sun, Yuting; Atmadibrata, Bernard; Yu, Denise; Wong, Matthew; Liu, Bing; Ho, Nicholas; Ling, Dora; Tee, Andrew E; Wang, Jenny; Mungrue, Imran N; Liu, Pei Y; Liu, Tao

    2017-09-01

    The N-Myc oncoprotein induces neuroblastoma by regulating gene transcription and consequently causing cell proliferation. Paradoxically, N-Myc is well known to induce apoptosis by upregulating pro-apoptosis genes, and it is not clear how N-Myc overexpressing neuroblastoma cells escape N-Myc-mediated apoptosis. The nuclear zinc finger protein LYAR has recently been shown to modulate gene expression by forming a protein complex with the protein arginine methyltransferase PRMT5. Here we showed that N-Myc upregulated LYAR gene expression by binding to its gene promoter. Genome-wide differential gene expression studies revealed that knocking down LYAR considerably upregulated the expression of oxidative stress genes including CHAC1, which depletes intracellular glutathione and induces oxidative stress. Although knocking down LYAR expression with siRNAs induced oxidative stress, neuroblastoma cell growth inhibition and apoptosis, co-treatment with the glutathione supplement N-acetyl-l-cysteine or co-transfection with CHAC1 siRNAs blocked the effect of LYAR siRNAs. Importantly, high levels of LYAR gene expression in human neuroblastoma tissues predicted poor event-free and overall survival in neuroblastoma patients, independent of the best current markers for poor prognosis. Taken together, our data suggest that LYAR induces proliferation and promotes survival of neuroblastoma cells by repressing the expression of oxidative stress genes such as CHAC1 and suppressing oxidative stress, and identify LYAR as a novel co-factor in N-Myc oncogenesis.

  15. 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.

  16. Hyaluronan in aged collagen matrix increases prostate epithelial cell proliferation

    PubMed Central

    Damodarasamy, Mamatha; Vernon, Robert B.; Chan, Christina K.; Plymate, Stephen R.; Wight, Thomas N.

    2015-01-01

    The extracellular matrix (ECM) of the prostate, which is comprised primarily of collagen, becomes increasingly disorganized with age, a property that may influence the development of hyperplasia and cancer. Collageous ECM extracted from the tails of aged mice exhibits many characteristics of collagen in aged tissues, including the prostate. When polymerized into a 3-dimensional (3D) gel, these collagen extracts can serve as models for the study of specific cell-ECM interactions. In the present study, we examined the behaviors of human prostatic epithelial cell lines representing normal prostate epithelial cells (PEC), benign prostatic hyperplasia (BPH-1), and adenocarcinoma (LNCaP) cultured in contact with 3D gels made from collagen extracts of young and aged mice. We found that proliferation of PEC, BPH-1, and LNCaP cells were all increased by culture on aged collagen gels relative to young collagen gels. In examining age-associated differences in the composition of the collagen extracts, we found that aged and young collagen had a similar amount of several collagen-associated ECM components, but aged collagen had a much greater content of the glycosaminoglycan hyaluronan (HA) than young collagen. The addition of HA (of similar size and concentration to that found in aged collagen extracts) to cells placed in young collagen elicited significantly increased proliferation in BPH-1 cells, but not in PEC or LNCaP cells, relative to controls not exposed to HA. Of note, histochemical analyses of human prostatic tissues showed significantly higher expression of HA in BPH and prostate cancer stroma relative to stroma of normal prostate. Collectively, these results suggest that changes in ECM involving increased levels of HA contribute to the growth of prostatic epithelium with aging. PMID:25124870

  17. Effects of Notch2 and Notch3 on Cell Proliferation and Apoptosis of Trophoblast Cell Lines.

    PubMed

    Zhao, Wei-Xiu; Zhuang, Xu; Huang, Tao-Tao; Feng, Ran; Lin, Jian-Hua

    2015-01-01

    To investigate the effect of Notch2 and Notch3 on cell proliferation and apoptosis of two trophoblast cell lines, BeWo and JAR. Notch2 and Notch3 expression in BeWo and JAR cells was upregulated or downregulated using lentivirus-mediated overexpression or RNA interference. The effect of Notch2 and Notch3 on cell proliferation was assessed by the CCK-8 assay. The effect of Notch2 and Notch3 on the apoptosis of BeWo and JAR cells was evaluated by flow cytometry using the Annexin V-PE Apoptosis kit. Lentivirus-based overexpression vectors were constructed by cloning the full-length coding sequences of human Notch2 and Notch3 C-terminally tagged with GFP or GFP alone (control) into a lentivirus-based expression vector. Lentivirus-based gene silencing vectors were prepared by cloning small interfering sequences targeting human Notch2 and Notch3 and scrambled control RNA sequence into a lentivirus-based gene knockdown vector. The effect of Notch2 and Notch3 on cell proliferation was assessed by the CCK-8 assay. And the effect of Notch2 and Notch3 on the apoptosis of BeWo and JAR cells was evaluated by flow cytometry using the Annexin V PE Apoptosis kit. We found that the downregulation of Notch2 and Notch3 gene expression in BeWo and JAR cells resulted in an increase in cell proliferation, while upregulation of Notch3 and Notch2 expression led to a decrease in cell proliferation. Moreover, the overexpression of Notch3 and Notch2 in BeWo and JAR cells reduced apoptosis in these trophoblast cell lines, whereas apoptosis was increased in the cells in which the expression of Notch3 and Notch2 was downregulated. Notch2 and Notch3 inhibited both cell proliferation and cell apoptosis in BeWo and JAR trophoblast cell lines.

  18. 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.

  19. CCDC106 promotes non-small cell lung cancer cell proliferation.

    PubMed

    Zhang, Xiupeng; Zheng, Qin; Wang, Chen; Zhou, Haijing; Jiang, Guiyang; Miao, Yuan; Zhang, Yong; Liu, Yang; Li, Qingchang; Qiu, Xueshan; Wang, Enhua

    2017-04-18

    Coiled-coil domain containing (CCDC) family members enhance tumor cell proliferation, and high CCDC protein levels correlate with unfavorable prognoses. Limited research demonstrated that CCDC106 may promote the degradation of p53/TP53 protein and inhibit its transactivity. The present study demonstrated that CCDC106 expression correlates with advanced TNM stage (P = 0.008), positive regional lymph node metastasis (P < 0.001), and poor overall survival (P < 0.001) in 183 non-small cell lung cancer cases. A549 and H1299 cells were selected as representative of CCDC106-low and CCDC106-high expressing cell lines, respectively. CCDC106 overexpression promoted A549 cell proliferation and xenograft tumor growth in nude mice, while siRNA-mediated CCDC106 knockdown inhibited H1299 cell proliferation. CCDC106 promoted AKT phosphorylation and upregulated the cell cycle-regulating proteins Cyclin A2 and Cyclin B1. Cell proliferation promoted by CCDC106 via Cyclin A2 and Cyclin B1 was rescued by treatment with the AKT inhibitor, LY294002. Our studies revealed that CCDC106 is associated with non-small cell lung cancer progression and unfavorable prognosis. CCDC106 enhanced Cyclin A2 and Cyclin B1 expression and promoted A549 and H1299 cell proliferation, which depended on AKT signaling. These results suggest that CCDC106 may be a novel target for lung cancer treatment.

  20. Elevated YAP and its downstream targets CCN1 and CCN2 in basal cell carcinoma: impact on keratinocyte proliferation and stromal cell activation.

    PubMed

    Quan, Taihao; Xu, Yiru; Qin, Zhaoping; Robichaud, Patrick; Betcher, Stephanie; Calderone, Ken; He, Tianyuan; Johnson, Timothy M; Voorhees, John J; Fisher, Gary J

    2014-04-01

    Yes-associated protein (YAP) is a transcriptional co-activator of hippo signaling pathway, which plays an important role in organ size control and tumorigenesis. Here we report that YAP and its downstream transcriptional targets CCN1 and CCN2 are markedly elevated in keratinocytes in human skin basal cell carcinoma tumor islands. In human keratinocytes, knockdown of YAP significantly reduced expression of CCN1 and CCN2, and repressed proliferation and survival. This inhibition of proliferation and survival was rescued by restoration of CCN1 expression, but not by CCN2 expression. In basal cell carcinoma stroma, CCN2-regulated genes type I collagen, fibronectin, and α-smooth muscle actin were highly expressed. Furthermore, atomic force microscopy revealed increased tissue stiffness in basal cell carcinoma stroma compared to normal dermis. These data provide evidence that up-regulation of YAP in basal cell carcinoma impacts both aberrant keratinocyte proliferation, via CCN1, and tumor stroma cell activation and stroma remodeling, via CCN2. Targeting YAP and/or CCN1 and CCN2 may provide clinical benefit in basal cell carcinoma. Copyright © 2014 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  1. DPPIV promotes endometrial carcinoma cell proliferation, invasion and tumorigenesis

    PubMed Central

    Yang, Xiaoqing; Zhang, Xinhua; Wu, Rongrong; Huang, Qicheng; Jiang, Yao; Qin, Jianbing; Yao, Feng; Jin, Guohua; Zhang, Yuquan

    2017-01-01

    Dipeptidyl peptidase IV (DPPIV), also known as CD26, is a 110-kDa cell surface glycoprotein expressed in various tissues. DPPIV reportedly plays a direct role in the progression of several human malignancies. DPPIV specific inhibitors are employed as antidiabetics and could potentially be repurposed to enhance anti-tumor immunotherapies. In the present study, we investigated the correlation between DPPIV expression and tumor progression in endometrial carcinoma (EC). DPPIV overexpression altered cell morphology and stimulated cell proliferation, invasion and tumorigenesis in vitro and in vivo. These effects were abrogated by DPPIV knockdown or pharmacological inhibition using sitagliptin. DPPIV overexpression increased hypoxia-inducible factor 1a (HIF-1a) and vascular endothelial growth factor A (VEGFA) expression to promote HIF-1a-VEGFA signaling. Our results indicated that DPPIV accelerated endometrial carcinoma progression and that sitagliptin may be an effective anti-EC therapeutic. PMID:28060721

  2. DPPIV promotes endometrial carcinoma cell proliferation, invasion and tumorigenesis.

    PubMed

    Yang, Xiaoqing; Zhang, Xinhua; Wu, Rongrong; Huang, Qicheng; Jiang, Yao; Qin, Jianbing; Yao, Feng; Jin, Guohua; Zhang, Yuquan

    2017-01-31

    Dipeptidyl peptidase IV (DPPIV), also known as CD26, is a 110-kDa cell surface glycoprotein expressed in various tissues. DPPIV reportedly plays a direct role in the progression of several human malignancies. DPPIV specific inhibitors are employed as antidiabetics and could potentially be repurposed to enhance anti-tumor immunotherapies. In the present study, we investigated the correlation between DPPIV expression and tumor progression in endometrial carcinoma (EC). DPPIV overexpression altered cell morphology and stimulated cell proliferation, invasion and tumorigenesis in vitro and in vivo. These effects were abrogated by DPPIV knockdown or pharmacological inhibition using sitagliptin. DPPIV overexpression increased hypoxia-inducible factor 1a (HIF-1a) and vascular endothelial growth factor A (VEGFA) expression to promote HIF-1a-VEGFA signaling. Our results indicated that DPPIV accelerated endometrial carcinoma progression and that sitagliptin may be an effective anti-EC therapeutic.

  3. Multi-gene fluorescence in situ hybridization to detect cell cycle gene copy number aberrations in young breast cancer patients

    PubMed Central

    Li, Chunyan; Bai, Jingchao; Hao, Xiaomeng; Zhang, Sheng; Hu, Yunhui; Zhang, Xiaobei; Yuan, Weiping; Hu, Linping; Cheng, Tao; Zetterberg, Anders; Lee, Mong-Hong; Zhang, J

    2014-01-01

    Breast cancer is a disease of cell cycle, and the dysfunction of cell cycle checkpoints plays a vital role in the occurrence and development of breast cancer. We employed multi-gene fluorescence in situ hybridization (M-FISH) to investigate gene copy number aberrations (CNAs) of 4 genes (Rb1, CHEK2, c-Myc, CCND1) that are involved in the regulation of cell cycle, in order to analyze the impact of gene aberrations on prognosis in the young breast cancer patients. Gene copy number aberrations of these 4 genes were more frequently observed in young breast cancer patients when compared with the older group. Further, these CNAs were more frequently seen in Luminal B type, Her2 overexpression, and tiple-negative breast cancer (TNBC) type in young breast cancer patients. The variations of CCND1, Rb1, and CHEK2 were significantly correlated with poor survival in the young breast cancer patient group, while the amplification of c-Myc was not obviously correlated with poor survival in young breast cancer patients. Thus, gene copy number aberrations (CNAs) of cell cycle-regulated genes can serve as an important tool for prognosis in young breast cancer patients. PMID:24621502

  4. Mesenchymal stem cells do not suppress lymphoblastic leukemic cell line proliferation.

    PubMed

    Mousavi Niri, Neda; Jaberipour, Mansooreh; Razmkhah, Mahboobeh; Ghaderi, Abbas; Habibagahi, Mojtaba

    2009-12-01

    Several studies have demonstrated the immunosuppresive effects of mesenchymal stem cells (MSCs) in allogeneic or mitogenic interactions. Cell-cell contact inhibition and secretion of suppressive soluble factors have been suggested in this regard. To investigate if adipose derived MSCs could inhibit Jurkat lymphoblastic leukemia T cell proliferation during coculture. Adherent cells with the ability of cellular growth were isolated from normal adipose tissues. Initial characterization of growing cells by flow cytometry suggested their mesenchymal stem cell characteristics. Cells were maintained in culture and used during third to fifth culture passages. Jurkat or allogeneic peripheral blood mononuclear cells (PBMCs) were labeled with carboxy fluorescein diacetate succinimidyl ester and cocultured with increasing doses of MSCs or MSC culture supernatant. Proliferation of PBMCs or Jurkat cells under these conditions was assessed by flow cytometry after 2 and 3 days of coculture, respectively. Results showed the expression of CD105, CD166 and CD44, and the absence of CD45, CD34 and CD14 on the surface of MSC like cells. Moreover, initial differentiation studies showed the potential of cell differentiation into hepatocytes. Comparison of Jurkat cell proliferation in the presence and absence of MSCs showed no significant difference, with 70% of cells displaying signs of at least one cell division. Similarly, the highest concentration of MSC culture supernatant (50% vol/vol) had no significant effect on Jurkat cell proliferation (p>0.6). The same MSC lots significantly suppressed the allogeneic PHA activated PBMCs under similar culture conditions. Using Jurkat cells as a model of leukemia T cells, our results indicated an uncertainty about the suppressive effect of MSCs and their inhibitory metabolites on tumor or leukemia cell proliferation. Additional systematic studies with MSCs of different sources are needed to fully characterize the immunological properties of MSCs

  5. Cell size control and a cell-intrinsic maturation program in proliferating oligodendrocyte precursor cells.

    PubMed

    Gao, F B; Raff, M

    1997-09-22

    We have used clonal analysis and time-lapse video recording to study the proliferative behavior of purified oligodendrocyte precursor cells isolated from the perinatal rat optic nerve growing in serum-free cultures. First, we show that the cell cycle time of precursor cells decreases with increasing concentrations of PDGF, the main mitogen for these cells, suggesting that PDGF levels may regulate the cell cycle time during development. Second, we show that precursor cells isolated from embryonic day 18 (E18) nerves differ from precursor cells isolated from postnatal day 7 (P7) or P14 nerves in a number of ways: they have a simpler morphology, and they divide faster and longer before they stop dividing and differentiate into postmitotic oligodendrocytes. Third, we show that purified E18 precursor cells proliferating in culture progressively change their properties to resemble postnatal cells, suggesting that progressive maturation is an intrinsic property of the precursors. Finally, we show that precursor cells, especially mature ones, sometimes divide unequally, such that one daughter cell is larger than the other; in each of these cases the larger daughter cell divides well before the smaller one, suggesting that the precursor cells, just like single-celled eucaryotes, have to reach a threshold size before they can divide. These and other findings raise the possibility that such stochastic unequal divisions, rather than the stochastic events occurring in G1 proposed by "transition probability" models, may explain the random variability of cell cycle times seen within clonal cell lines in culture.

  6. CXCL7 promotes proliferation and invasion of cholangiocarcinoma cells.

    PubMed

    Guo, Qian; Jian, Zhixiang; Jia, Baoqing; Chang, Liang

    2017-02-01

    CXCL7 is an important chemoattractant cytokine, which signals through binding to its receptor CXCR2. Recent studies have demonstrated that the CXCL7/CXCR2 signaling plays a promoting role in several common malignancies, including lung, renal, colon, and breast cancer. However, the regulatory role of CXCL7, in cholangiocarcinoma, as well as the underlying mechanism, has not been previously reported. Herein, we found more positive expression of CXCL7 in cholangiocarcinoma tissues compared to adjacent non-tumor tissues. High CXCL7 expression was significantly correlated with poor differentiation, lymph node metastasis, vascular invasion and advanced clinical stage, but was not associated with age, gender, or tumor size. Besides, the expression of CXCL7 was significantly associated with the Ki67 expression, but not associated with CA199, AFP, or P53 expression in cholangiocarcinoma. Moreover, the overall survival of cholangiocarcinoma patients with high CXCL7 expression was significantly shorter than those with low CXCL7 expression. In vitro study indicated that CXCL7 and CXCR2 were also positively expressed in several common cholangiocarcinoma cell lines, including HuCCT1, HuH28, QBC939, EGI-1, OZ and WITT. SiRNA-induced inhibition of CXCL7 significantly reduced the proliferation and invasion of QBC939 cells. On the contrary, overexpression of CXCL7 markedly promoted these malignant phenotypes of QBC939 cells. Of note, the conditioned medium of CXCL7-overexpresing human hepatic stellate cells could also promote the proliferation and invasion of QBC939 cells, suggesting that CXCL7 may also play an oncogenic role in cholangiocarcinoma in a paracrine-dependent manner, not only in an autocrine-dependent manner. Molecular assay data suggested that the AKT signaling pathway was involved in the CXCL7-mediated malignant phenotypes of QBC939 cells. In summary, our study suggests that CXCL7 plays a promoting role in regulating the growth and metastasis of cholangiocarcinoma.

  7. Cell proliferation and plant development under novel altered gravity environments.

    PubMed

    Herranz, R; Medina, F J

    2014-01-01

    Gravity is a key factor for life on Earth. It is the only environmental factor that has remained constant throughout evolution, and plants use it to modulate important physiological activities; gravity removal or alteration produces substantial changes in essential functions. For root gravitropism, gravity is sensed in specialised cells, which are capable of detecting magnitudes of the g vector lower than 10(-3) . Then, the mechanosignal is transduced to upper zones of the root, resulting in changes in the lateral distribution of auxin and in the rate of auxin polar transport. Gravity alteration has consequences for cell growth and proliferation rates in root meristems, which are the basis of the developmental programme of a plant, in which regulation via auxin is involved. The effect is disruption of meristematic competence, i.e. the strict coordination between cell proliferation and growth, which characterises meristematic cells. This effect can be related to changes in the transport and distribution of auxin throughout the root. However, similar effects of gravity alteration have been found in plant cell cultures in vitro, in which neither specialised structures for gravity sensing and signal transduction, nor apparent gravitropism have been described. We postulate that gravity resistance, a general mechanism of cellular origin for developing rigid structures in plants capable of resisting the gravity force, could also be responsible for the changes in cell growth and proliferation parameters detected in non-specialised cells. The mechanisms of gravitropism and graviresistance are complementary, the first being mostly sensitive to the direction of the gravity vector, and the second to its magnitude. At a global molecular level, the consequence of gravity alteration is that the genome should be finely tuned to counteract a type of stress that plants have never encountered before throughout evolution. Multigene families and redundant genes present an advantage in

  8. Aberrant Promoter Hypermethylation of RASSF Family Members in Merkel Cell Carcinoma

    PubMed Central

    Richter, Antje M.; Haag, Tanja; Walesch, Sara; Herrmann-Trost, Peter; Marsch, Wolfgang C.; Kutzner, Heinz; Helmbold, Peter; Dammann, Reinhard H.

    2013-01-01

    Merkel cell carcinoma (MCC) is one of the most aggressive cancers of the skin. RASSFs are a family of tumor suppressors that are frequently inactivated by promoter hypermethylation in various cancers. We studied CpG island promoter hypermethylation in MCC of RASSF2, RASSF5A, RASSF5C and RASSF10 by combined bisulfite restriction analysis (COBRA) in MCC samples and control tissue. We found RASSF2 to be methylated in three out of 43 (7%), RASSF5A in 17 out of 39 (44%, but also 43% in normal tissue), RASSF5C in two out of 26 (8%) and RASSF10 in 19 out of 84 (23%) of the cancer samples. No correlation between the methylation status of the analyzed RASSFs or between RASSF methylation and MCC characteristics (primary versus metastatic, Merkel cell polyoma virus infection, age, sex) was found. Our results show that RASSF2, RASSF5C and RASSF10 are aberrantly hypermethylated in MCC to a varying degree and this might contribute to Merkel cell carcinogenesis. PMID:24252868

  9. COPD and squamous cell lung cancer: aberrant inflammation and immunity is the common link.

    PubMed

    Bozinovski, Steven; Vlahos, Ross; Anthony, Desiree; McQualter, Jonathan; Anderson, Gary; Irving, Louis; Steinfort, Daniel

    2016-02-01

    Cigarette smoking has reached epidemic proportions within many regions of the world and remains the highest risk factor for chronic obstructive pulmonary disease (COPD) and lung cancer. Squamous cell lung cancer is commonly detected in heavy smokers, where the risk of developing lung cancer is not solely defined by tobacco consumption. Although therapies that target common driver mutations in adenocarcinomas are showing some promise, they are proving ineffective in smoking-related squamous cell lung cancer. Since COPD is characterized by an excessive inflammatory and oxidative stress response, this review details how aberrant innate, adaptive and systemic inflammatory processes can contribute to lung cancer susceptibility in COPD. Activated leukocytes release increasing levels of proteases and free radicals as COPD progresses and tertiary lymphoid aggregates accumulate with increasing severity. Reactive oxygen species promote formation of reactive carbonyls that are not only tumourigenic through initiating DNA damage, but can directly alter the function of regulatory proteins involved in host immunity and tumour suppressor functions. Systemic inflammation is also markedly increased during infective exacerbations in COPD and the interplay between tumour-promoting serum amyloid A (SAA) and IL-17A is discussed. SAA is also an endogenous allosteric modifier of FPR2 expressed on immune and epithelial cells, and the therapeutic potential of targeting this receptor is proposed as a novel strategy for COPD-lung cancer overlap. © 2015 The British Pharmacological Society.

  10. Nuclear orphan receptor TLX affects gene expression, proliferation and cell apoptosis in beta cells.

    PubMed

    Shi, Xiaoli; Xiong, Xiaokan; Dai, Zhe; Deng, Haohua; Sun, Li; Hu, Xuemei; Zhou, Feng; Xu, Yancheng

    Nuclear orphan receptor TLX is an essential regulator of the growth of neural stem cells. However, its exact function in pancreatic islet cells is still unknown. In the present study, gene expression profiling analysis revealed that overexpression of TLX in beta cell line MIN6 causes suppression of 176 genes and upregulation of 49 genes, including a cadre of cell cycle, cell proliferation and cell death control genes, such as Btg2, Ddit3 and Gadd45a. We next examined the effects of TLX overexpression on proliferation, apoptosis and insulin secretion in MIN6 cells. Proliferation analysis using EdU assay showed that overexpression of TLX increased percentage of EdU-positive cells. Cell cycle and apoptosis analysis revealed that overexpression of TLX in MIN6 cells resulted in higher percentage of cells exiting G1 into S-phase, and a 58.8% decrease of cell apoptosis induced by 0.5 mM palmitate. Moreover, TLX overexpression did not cause impairment of insulin secretion. Together, we conclude that TLX is among factors capable of controlling beta cell proliferation and survival, which may serve as a target for the development of novel therapies for diabetes. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Inter- and Intra-Chromosomal Aberrations in Human Cells Exposed in vitro to High and Low LET Radiations

    NASA Technical Reports Server (NTRS)

    Hada, M.; Wilkins, R.; Saganti, P. B.; Gersey, B.; Cucinotta, F. A.; Wu, H.

    2006-01-01

    Energetic heavy ions pose a health risk to astronauts in extended ISS and future Mars missions. High-LET heavy ions are particularly effective in causing various biological effects including cell inactivation, genetic mutations and cancer induction. Most of these biological endpoints are closely related to chromosomal damage, which can be utilized as a biomarker for radiation insults. Previously, we had studied chromosome aberrations in human lymphocytes and fibroblasts induced by both low- and high-LET radiation using FISH and multicolor fluorescence in situ hybridization (mFISH) techniques. In this study, we exposed human epithelial cells in vitro to gamma rays and energetic particles of varying types and energies and dose rates, and analyzed chromosomal damages using the multicolor banding in situ hybridization (mBAND) procedure. Confluent human epithelial cells (CH184B5F5/M10) were exposed to energetic heavy ions at NASA Space Radiation Laboratory (NSRL) at the Brookhaven National Laboratory, high energy neutron at the Los Alamos Nuclear Science Center (LANSCE) or Cs-137-gamma radiation source at the University of Texas, MD Anderson Cancer Center. After colcemid and Calyculin A treatment, cells were fixed and painted with XCyte3 mBAND kit (MetaSystems) and chromosome aberrations were analyzed with mBAND analysis system (MetaSystems). With this technique, individually painted chromosomal bands on one chromosome allowed the identification of interchromosomal aberrations (translocation to unpainted chromosomes) and intrachromosomal aberrations (inversions and deletions within a single painted chromosome). The results of the mBAND study showed a higher ratio of inversion involved with interchromosomal exchange in heavy ions compared to -ray irradiation. Analysis of chromosome aberrations using mBAND has the potential to provide useful information on human cell response to space-like radiation.

  12. Chromosome aberrations in T lymphocytes carrying adult T-cell leukemia-associated antigens (ATLA) from healthy adults.

    PubMed

    Fukuhara, S; Hinuma, Y; Gotoh, Y I; Uchino, H

    1983-01-01

    Chromosomes were studied in cultured T lymphocytes carrying adult T-cell leukemia-associated antigens (ATLA) that were obtained from five Japanese anti-ATLA seropositive healthy adults. Chromosomally abnormal cells were observed in three of the five healthy adults, and these cells were clonal in two subjects. All cells examined in one subject had rearrangements of chromosome nos. 7 and 14. Clonal cells from the second had a minute chromosome of unknown origin. A few cells in the third had nonclonal rearrangements of chromosomes. Thus, ATLA-positive T lymphocytes in some anti-ATLA seropositive healthy people have chromosome aberrations.

  13. Analysis of Radiation-Induced Chromosomal Aberrations on a Cell-by-Cell Basis after Alpha-Particle Microbeam Irradiation: Experimental Data and Simulations.

    PubMed

    Testa, Antonella; Ballarini, Francesca; Giesen, Ulrich; Gil, Octávia Monteiro; Carante, Mario P; Tello, John; Langner, Frank; Rabus, Hans; Palma, Valentina; Pinto, Massimo; Patrono, Clarice

    2018-06-01

    There is a continued need for further clarification of various aspects of radiation-induced chromosomal aberration, including its correlation with radiation track structure. As part of the EMRP joint research project, Biologically Weighted Quantities in Radiotherapy (BioQuaRT), we performed experimental and theoretical analyses on chromosomal aberrations in Chinese hamster ovary cells (CHO-K1) exposed to α particles with final energies of 5.5 and 17.8 MeV (absorbed doses: ∼2.3 Gy and ∼1.9 Gy, respectively), which were generated by the microbeam at the Physikalisch-Technische Bundesanstalt (PTB) in Braunschweig, Germany. In line with the differences in linear energy transfer (approximately 85 keV/μm for 5.5 MeV and 36 keV/μm for 17.8 MeV α particles), the 5.5 MeV α particles were more effective than the 17.8 MeV α particles, both in terms of the percentage of aberrant cells (57% vs. 33%) and aberration frequency. The yield of total aberrations increased by a factor of ∼2, although the increase in dicentrics plus centric rings was less pronounced than in acentric fragments. The experimental data were compared with Monte Carlo simulations based on the BIophysical ANalysis of Cell death and chromosomal Aberrations model (BIANCA). This comparison allowed interpretation of the results in terms of critical DNA damage [cluster lesions (CLs)]. More specifically, the higher aberration yields observed for the 5.5 MeV α particles were explained by taking into account that, although the nucleus was traversed by fewer particles (nominally, 11 vs. 25), each particle was much more effective (by a factor of ∼3) at inducing CLs. This led to an increased yield of CLs per cell (by a factor of ∼1.4), consistent with the increased yield of total aberrations observed in the experiments.

  14. MiR-1 suppresses tumor cell proliferation in colorectal cancer by inhibition of Smad3-mediated tumor glycolysis

    PubMed Central

    Xu, Wanfu; Zhang, Zijing; Zou, Kejian; Cheng, Yang; Yang, Min; Chen, Huan; Wang, Hongli; Zhao, Junhong; Chen, Peiyu; He, Liying; Chen, Xinwen; Geng, Lanlan; Gong, Sitang

    2017-01-01

    Aberrant expression of microRNA (miR)-1 has been observed in many human malignancies. However, the function and underlying mechanism of miR-1 remains elusive. To address the specific role of miR-1 in tumor glycolysis using the gain- or loss-of-function studies. Metabolic studies combined with gene expression analysis were performed in vitro and in vivo. We demonstrated aberrant expression of miR-1 in aerobic glycolysis, the Warburg effect, in cancer cells. MiR-1 suppressed aerobic glycolysis and tumor cell proliferation via inactivation of Smad3 and targeting HIF-1α, leading to reduce HK2 and MCT4 expression, which illustrated a novel pathway to mediate aerobic glycolysis in cancer cells. Overexpression of miR-1 mimics significantly decreased tumor glycolysis, including lactate production and glucose uptake, and cell proliferation, and these effects were reversed by ectopic expression of Smad3. Importantly, endogenous Smad3 regulated and interacted with HIF-1α, resulting in increasing activity of Smad3, and this interaction was dramatically abolished by addition of miR-1. We further demonstrated that Smad3 was central to the effects of miR-1 in colorectal cancer cells, establishing a previously unappreciated mechanism by which the miR-1/Smad3/HIF-1α axis facilitates the Warburg effect to promote cancer progression in vitro and in vivo. The results indicate that miR-1 may have an essential role as a tumor suppressor, suggesting its potential role in molecular therapy of patients with advanced colorectal cancer. PMID:28471448

  15. Analysis of Chromosomal Aberrations after Low and High Dose Rate Gamma Irradiation in ATM or NBS Suppressed Human Fibroblast Cells

    NASA Technical Reports Server (NTRS)

    Hada, M.; Huff, J. L.; Patel, Z.; Pluth, J. M.; George, K. A.; Cucinotta, F. A.

    2009-01-01

    A detailed understanding of the biological effects of heavy nuclei is needed for space radiation protection and for cancer therapy. High-LET radiation produces more complex DNA lesions that may be non-repairable or that may require additional processing steps compared to endogenous DSBs, increasing the possibility of misrepair. Interplay between radiation sensitivity, dose, and radiation quality has not been studied extensively. Previously we studied chromosome aberrations induced by low- and high- LET radiation in several cell lines deficient in ATM (ataxia telangactasia mutated; product of the gene that is mutated in ataxia telangiectasia patients) or NBS (nibrin; product of the gene mutated in the Nijmegen breakage syndrome), and gliomablastoma cells that are proficient or lacking in DNA-dependent protein kinase (DNA-PK) activity. We found that the yields of both simple and complex chromosomal aberrations were significantly increased in the DSB repair defective cells compared to normal cells. The increased aberrations observed for the ATM and NBS defective lines was due to a significantly larger quadratic dose-response term compared to normal fibroblasts for both simple and complex aberrations, while the linear dose-response term was significantly higher in NBS cells only for simple exchanges. These results point to the importance of the functions of ATM and NBS in chromatin modifications that function to facilitate correct DSB repair and minimize aberration formation. To further understand the sensitivity differences that were observed in ATM and NBS deficient cells, in this study, chromosomal aberration analysis was performed in normal lung fibroblast cells treated with KU-55933, a specific ATM kinase inhibitor, or Mirin, an MRN complex inhibitor involved in activation of ATM. We are also testing siRNA knockdown of these proteins. Normal and ATM or NBS suppressed cells were irradiated with gamma-rays and chromosomes were collected with a premature chromosome

  16. Amino acids rather than glucose account for the majority of cell mass in proliferating mammalian cells

    PubMed Central

    Hosios, Aaron M.; Hecht, Vivian C.; Danai, Laura V.; Johnson, Marc O.; Rathmell, Jeffrey C.; Steinhauser, Matthew L.; Manalis, Scott R.; Vander Heiden, Matthew G.

    2016-01-01

    Cells must duplicate their mass in order to proliferate. Glucose and glutamine are the major nutrients consumed by proliferating mammalian cells, but the extent to which these and other nutrients contribute to cell mass is unknown. We quantified the fraction of cell mass derived from different nutrients and find that the majority of carbon mass in cells is derived from other amino acids, which are consumed at much lower rates than glucose and glutamine. While glucose carbon has diverse fates, glutamine contributes most to protein, and this suggests that glutamine’s ability to replenish TCA cycle intermediates (anaplerosis) is primarily used for amino acid biosynthesis. These findings demonstrate that rates of nutrient consumption are indirectly associated with mass accumulation and suggest that high rates of glucose and glutamine consumption support rapid cell proliferation beyond providing carbon for biosynthesis. PMID:26954548

  17. miR-340 inhibits glioblastoma cell proliferation by suppressing CDK6, cyclin-D1 and cyclin-D2

    SciTech Connect

    Li, Xuesong; Gong, Xuhai; Chen, Jing

    Glioblastoma development is often associated with alteration in the activity and expression of cell cycle regulators, such as cyclin-dependent kinases (CKDs) and cyclins, resulting in aberrant cell proliferation. Recent studies have highlighted the pivotal roles of miRNAs in controlling the development and growth of glioblastoma. Here, we provide evidence for a function of miR-340 in the inhibition of glioblastoma cell proliferation. We found that miR-340 is downregulated in human glioblastoma tissue samples and several established glioblastoma cell lines. Proliferation and neurosphere formation assays revealed that miR-340 plays an oncosuppressive role in glioblastoma, and that its ectopic expression causes significant defectmore » in glioblastoma cell growth. Further, using bioinformatics, luciferase assay and western blot, we found that miR-340 specifically targets the 3′UTRs of CDK6, cyclin-D1 and cyclin-D2, leading to the arrest of glioblastoma cells in the G0/G1 cell cycle phase. Confirming these results, we found that re-introducing CDK6, cyclin-D1 or cyclin-D2 expression partially, but significantly, rescues cells from the suppression of cell proliferation and cell cycle arrest mediated by miR-340. Collectively, our results demonstrate that miR-340 plays a tumor-suppressive role in glioblastoma and may be useful as a diagnostic biomarker and/or a therapeutic avenue for glioblastoma. - Highlights: • miR-340 is downregulated in glioblastoma samples and cell lines. • miR-340 inhibits glioblastoma cell proliferation. • miR-340 directly targets CDK6, cyclin-D1, and cyclin-D2. • miR-340 regulates glioblastoma cell proliferation via CDK6, cyclin-D1 and cyclin-D2.« less

  18. 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

  19. 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.

  20. Endogenous Hydrogen Sulfide Enhances Cell Proliferation of Human Gastric Cancer AGS Cells.

    PubMed

    Sekiguchi, Fumiko; Sekimoto, Teruki; Ogura, Ayaka; Kawabata, Atsufumi

    2016-01-01

    Hydrogen sulfide (H2S), the third gasotransmitter, is endogenously generated by certain H2S synthesizing enzymes, including cystathionine-γ-lyase (CSE) and cystathionine-β-synthase (CBS) from L-cysteine in the mammalian body. Several studies have shown that endogenous and exogenous H2S affects the proliferation of cancer cells, although the effects of H2S appear to vary with cell type, being either promotive or suppressive. In the present study, we determined whether endogenously formed H2S regulates proliferation in human gastric cancer AGS cells. CSE, but not CBS, was expressed in AGS cells. CSE inhibitors, DL-propargylglycine (PPG) and β-cyano-L-alanine (BCA), significantly suppressed the proliferation of AGS cells in a concentration-dependent manner. CSE inhibitors did not increase lactate dehydrogenase (LDH) release in the same concentration range. The inhibitory effects of PPG and BCA on cell proliferation were reversed by repetitive application of NaHS, a donor of H2S. Interestingly, nuclear condensation and fragmentation were detected in AGS cells treated with PPG or BCA. These results suggest that endogenous H2S produced by CSE may contribute to the proliferation of gastric cancer AGS cells, most probably through anti-apoptotic actions.

  1. mTOR-Dependent Cell Proliferation in the Brain.

    PubMed

    Ryskalin, Larisa; Lazzeri, Gloria; Flaibani, Marina; Biagioni, Francesca; Gambardella, Stefano; Frati, Alessandro; Fornai, Francesco

    2017-01-01

    The mammalian Target of Rapamycin (mTOR) is a molecular complex equipped with kinase activity which controls cell viability being key in the PI3K/PTEN/Akt pathway. mTOR acts by integrating a number of environmental stimuli to regulate cell growth, proliferation, autophagy, and protein synthesis. These effects are based on the modulation of different metabolic pathways. Upregulation of mTOR associates with various pathological conditions, such as obesity, neurodegeneration, and brain tumors. This is the case of high-grade gliomas with a high propensity to proliferation and tissue invasion. Glioblastoma Multiforme (GBM) is a WHO grade IV malignant, aggressive, and lethal glioma. To date, a few treatments are available although the outcome of GBM patients remains poor. Experimental and pathological findings suggest that mTOR upregulation plays a major role in determining an aggressive phenotype, thus determining relapse and chemoresistance. Among several activities, mTOR-induced autophagy suppression is key in GBM malignancy. In this article, we discuss recent evidence about mTOR signaling and its role in normal brain development and pathological conditions, with a special emphasis on its role in GBM.

  2. mTOR-Dependent Cell Proliferation in the Brain

    PubMed Central

    Lazzeri, Gloria; Frati, Alessandro

    2017-01-01

    The mammalian Target of Rapamycin (mTOR) is a molecular complex equipped with kinase activity which controls cell viability being key in the PI3K/PTEN/Akt pathway. mTOR acts by integrating a number of environmental stimuli to regulate cell growth, proliferation, autophagy, and protein synthesis. These effects are based on the modulation of different metabolic pathways. Upregulation of mTOR associates with various pathological conditions, such as obesity, neurodegeneration, and brain tumors. This is the case of high-grade gliomas with a high propensity to proliferation and tissue invasion. Glioblastoma Multiforme (GBM) is a WHO grade IV malignant, aggressive, and lethal glioma. To date, a few treatments are available although the outcome of GBM patients remains poor. Experimental and pathological findings suggest that mTOR upregulation plays a major role in determining an aggressive phenotype, thus determining relapse and chemoresistance. Among several activities, mTOR-induced autophagy suppression is key in GBM malignancy. In this article, we discuss recent evidence about mTOR signaling and its role in normal brain development and pathological conditions, with a special emphasis on its role in GBM. PMID:29259984

  3. Generalized time-dependent model of radiation-induced chromosomal aberrations in normal and repair-deficient human cells.

    PubMed

    Ponomarev, Artem L; George, Kerry; Cucinotta, Francis A

    2014-03-01

    We have developed a model that can simulate the yield of radiation-induced chromosomal aberrations (CAs) and unrejoined chromosome breaks in normal and repair-deficient cells. The model predicts the kinetics of chromosomal aberration formation after exposure in the G₀/G₁ phase of the cell cycle to either low- or high-LET radiation. A previously formulated model based on a stochastic Monte Carlo approach was updated to consider the time dependence of DNA double-strand break (DSB) repair (proper or improper), and different cell types were assigned different kinetics of DSB repair. The distribution of the DSB free ends was derived from a mechanistic model that takes into account the structure of chromatin and DSB clustering from high-LET radiation. The kinetics of chromosomal aberration formation were derived from experimental data on DSB repair kinetics in normal and repair-deficient cell lines. We assessed different types of chromosomal aberrations with the focus on simple and complex exchanges, and predicted the DSB rejoining kinetics and misrepair probabilities for different cell types. The results identify major cell-dependent factors, such as a greater yield of chromosome misrepair in ataxia telangiectasia (AT) cells and slower rejoining in Nijmegen (NBS) cells relative to the wild-type. The model's predictions suggest that two mechanisms could exist for the inefficiency of DSB repair in AT and NBS cells, one that depends on the overall speed of joining (either proper or improper) of DNA broken ends, and another that depends on geometric factors, such as the Euclidian distance between DNA broken ends, which influences the relative frequency of misrepair.

  4. Annexin 2A sustains glioblastoma cell dissemination and proliferation

    PubMed Central

    Maule, Francesca; Bresolin, Silvia; Rampazzo, Elena; Boso, Daniele; Puppa, Alessandro Della; Esposito, Giovanni; Porcù, Elena; Mitola, Stefania; Lombardi, Giuseppe; Accordi, Benedetta; Tumino, Manuela; Basso, Giuseppe; Persano, Luca

    2016-01-01

    Glioblastoma (GBM) is the most devastating tumor of the brain, characterized by an almost inevitable tendency to recur after intensive treatments and a fatal prognosis. Indeed, despite recent technical improvements in GBM surgery, the complete eradication of cancer cell disseminated outside the tumor mass still remains a crucial issue for glioma patients management. In this context, Annexin 2A (ANXA2) is a phospholipid-binding protein expressed in a variety of cell types, whose expression has been recently associated with cell dissemination and metastasis in many cancer types, thus making ANXA2 an attractive putative regulator of cell invasion also in GBM. Here we show that ANXA2 is over-expressed in GBM and positively correlates with tumor aggressiveness and patient survival. In particular, we associate the expression of ANXA2 to a mesenchymal and metastatic phenotype of GBM tumors. Moreover, we functionally characterized the effects exerted by ANXA2 inhibition in primary GBM cultures, demonstrating its ability to sustain cell migration, matrix invasion, cytoskeletal remodeling and proliferation. Finally, we were able to generate an ANXA2-dependent gene signature with a significant prognostic potential in different cohorts of solid tumor patients, including GBM. In conclusion, we demonstrate that ANXA2 acts at multiple levels in determining the disseminating and aggressive behaviour of GBM cells, thus proving its potential as a possible target and strong prognostic factor in the future management of GBM patients. PMID:27429043

  5. Effects of spaceflight on the proliferation of jejunal mucosal cells

    NASA Technical Reports Server (NTRS)

    Phillips, Robert W.; Moeller, C. L.; Sawyer, Heywood R.; Smirnov, K. L.

    1991-01-01

    The purpose of this project was to test the hypothesis that the generalized, whole body decrease in synthetic activity due to microgravity conditions encountered during spaceflight would be demonstrable in cells and tissues characterized by a rapid rate of turnover. Jejunal mucosal cells were chosen as a model since these cells are among the most rapidly proliferating in the body. Accordingly, the percentage of mitotic cells present in the crypts of Lieberkuhn in each of 5 rats flown on the COSMOS 2044 mission were compared to the percentage of mitotic cells present in the crypts in rats included in each of 3 ground control groups (i.e., vivarium, synchronous and caudal-elevated). No significant difference (p greater than .05) was detected in mitotic indices between the flight and vivarium group. Although the ability of jejunal mucosal cells to divide by mitosis was not impaired in flight group, there was, however, a reduction in the length of villi and depth of crypts. The concommitant reduction in villus length and crypth depth in the flight group probably reflects changes in connective tissue components within the core of villi.

  6. Clonal variation in proliferation rate of cultures of GPK cells.

    PubMed

    Riley, P A; Hola, M

    1981-09-01

    Pedigrees of twenty-six clones of a line of keratocytes derived from guinea-pig ear epidermis (GPK cells) were analysed from time-lapse film. The mean interdivision time (IDT) for the culture was 1143 +/- 215 (SD) min. The mean generation rates (mean reciprocal interdivision times) of clones varied over a range of 3.93--10.2 x 10(-4)/min and the standard deviation of the clonal mean generation rates was 16.8% of the average value. Transient intraclonal variations in IDT due to mitoses in a plane perpendicular to the substratum were observed. The data were also analysed on the basis of cell location in sixteen equal zones (quadrats) of the filmed area. The mean generation rate of quadrats was 8.73 x 10(-4)/min (SD = 4.9%). The spatial distribution showed some clustering of cells. The mean local density of the clones (2.25 +/- 0.62 cells/10(-4) cm2) was significantly higher than the quadrat density (1.76 +/- 0.8 cells/10(-4) cm2). There was no significant correlation between clonal density and mean generation rates, whereas for quadrats a significant negative correlation was found (P = 2.7%). The results support the proposition that cell lineage is the major determinant of the proliferation rate of subconfluent cultures.

  7. Indomethacin derivatives as tubulin stabilizers to inhibit cancer cell proliferation.

    PubMed

    Chennamaneni, Snigdha; Gan, Chunfang; Lama, Rati; Zhong, Bo; Su, Bin

    2016-01-15

    Cyclooxygenase (COX) inhibitor Indomethacin analogs exhibited more potent cancer cell growth inhibition and apoptosis inducing activities than the parental compound. The anti-proliferative mechanism investigation of the analogs revealed that they inhibited tubulin polymerization at high concentrations whereas enhanced polymerization at low concentrations. The two opposite activities might antagonize each other and impaired the anti-proliferative activity of the derivatives eventually. In this study, we further performed lead optimization based on the structure activity relationship (SAR) generated. One of the new Indomethacin derivatives compound 11 {2-(4-(benzyloxy)phenyl)-N-(1-(4-bromobenzoyl)-3-(2-((2-(dimethylamino)ethyl)amino)-2-oxoethyl)-2-methyl-1H-indol-5-yl)acetamide} inhibited the proliferation of a panel of cancer cell lines with IC50s at the sub-micromole levels. Further study revealed that the compound only enhanced tubulin polymerization and was a tubulin stabilizer. Published by Elsevier Ltd.

  8. Peripheral nerve pathology, including aberrant Schwann cell differentiation, is ameliorated by doxycycline in a laminin-α2-deficient mouse model of congenital muscular dystrophy

    PubMed Central

    Homma, Sachiko; Beermann, Mary Lou; Miller, Jeffrey Boone

    2011-01-01

    The most common form of childhood congenital muscular dystrophy, Type 1A (MDC1A), is caused by mutations in the human LAMA2 gene that encodes the laminin-α2 subunit. In addition to skeletal muscle deficits, MDC1A patients typically show a loss of peripheral nerve function. To identify the mechanisms underlying this loss of nerve function, we have examined pathology and cell differentiation in sciatic nerves and ventral roots of the laminin-α2-deficient (Lama2−/−) mice, which are models for MDC1A. We found that, compared with wild-type, sciatic nerves of Lama2−/− mice had a significant increase in both proliferating (Ki67+) cells and premyelinating (Oct6+) Schwann cells, but also had a significant decrease in both immature/non-myelinating [glial fibrillary acidic protein (GFAP)+] and myelinating (Krox20+) Schwann cells. To extend our previous work in which we found that doxycycline, which has multiple effects on mammalian cells, improves motor behavior and more than doubles the median life-span of Lama2−/− mice, we also determined how nerve pathology was affected by doxycycline treatment. We found that myelinating (Krox20+) Schwann cells were significantly increased in doxycycline-treated compared with untreated sciatic nerves. In addition, doxycycline-treated peripheral nerves had significantly less pathology as measured by assays such as amount of unmyelinated or disorganized axons. This study thus identified aberrant proliferation and differentiation of Schwann cells as key components of pathogenesis in peripheral nerves and provided proof-of-concept that pharmaceutical therapy can be of potential benefit for peripheral nerve dysfunction in MDC1A. PMID:21505075

  9. [Inhibition effects of black rice pericarp extracts on cell proliferation of PC-3 cells].

    PubMed

    Jiang, Weiwei; Yu, Xudong; Ren, Guofeng

    2013-05-01

    To observe the inhibitive effects of black rice pericarp extracts on cell proliferation of human prostate cancer cell PC-3 and to explore its effecting mechanism. The black rice pericarp extract was used to treat the PC-3 cells. The inhibitory effect of black rice pericarp extract on cells proliferation of PC-3 was tested by MTT method. Cell apoptosis rates and cell cycle were measured by flow cytometric assay (FCM). Western blot was used to study the protein expression levels of p38, p-p38, JNK, p-JNK. A dose-dependent and time-dependent proliferation inhibition of black rice pericarp extract was demonstrated in PC-3. The most prominent experiment condition was inhibitory concentration with 300microg/ml and treated for 72 h. The experiment result of flow cytometry analysis demonstrates that the apoptosis rate of PC-3 cells increased along with the increasing of black rice pericarp extract concentration, and a G1-S cell cycle arrest was induced in a dose-dependent manner. After PC-3 cell was treated with black rice pericarp extract for 72 h, the expressions of p-p38, p-JNK protein increased. Black rice pericarp extract could inhibit proliferation, change the cell cycle distributions and induce apoptosis in human prostatic cancer cell PC-3. Its inhibitory effect may be through promoting activation of the JNK, p38 signaling pathway. These results suggest that black rice pericarp extract maybe has an inhibitory effect on prostatic cancer.

  10. Aberrant Expression of Xist in Aborted Porcine Fetuses Derived from Somatic Cell Nuclear Transfer Embryos

    PubMed Central

    Yuan, Lin; Wang, Anfeng; Yao, Chaogang; Huang, Yongye; Duan, Feifei; Lv, Qinyan; Wang, Dongxu; Ouyang, Hongsheng; Li, Zhanjun; Lai, Liangxue

    2014-01-01

    Cloned pigs generated by somatic cell nuclear transfer (SCNT) show a greater ratio of early abortion during mid-gestation than normal controls. X-linked genes have been demonstrated to be important for the development of cloned embryos. To determine the relationship between the expression of X-linked genes and abortion of cloned porcine fetuses, the expression of X-linked genes were investigated by quantitative real-time polymerase chain reaction (q-PCR) and the methylation status of Xist DMR was performed by bisulfate-specific PCR (BSP). q-PCR analysis indicated that there was aberrant expression of X-linked genes, especially the upregulated expression of Xist in both female and male aborted fetuses compared to control fetuses. Results of BSP suggested that hypomethylation of Xist occurred in aborted fetuses, whether male or female. These results suggest that the abnormal expression of Xist may be associated with the abortion of fetuses derived from somatic cell nuclear transfer embryos. PMID:25429426

  11. Hippo pathway regulates somatic development and cell proliferation of silkworm.

    PubMed

    Li, Niannian; Tong, Xiaoling; Zeng, Jie; Meng, Gang; Sun, Fuze; Hu, Hai; Song, Jiangbo; Lu, Cheng; Dai, Fangyin

    2018-03-01

    Hippo signaling pathway (signaling pathway Hippo, hereinafter referred to as the Hippo pathway) was the earliest found in Drosophila (Schneck [1]), which can regulate the development of tissues and organs, even some components of the pathway were identified as tumor suppressor [2]. The pathway was more concerned in fruit flies and mice (Schneck [1]), but little attention has been given in silkworm, an important economic and lepidopteran model insect. In this manuscript, we identified major Hippo pathway related genes (Hippo, Salvador, Warts, Mats, Yorkie) in silkworm and named BmHpo, BmSav, BmWts, BmMats, BmYki. The domain organization of these genes was highly conserved in silkworm and other organisms suggesting that they could use similar protein-protein interactions to construct the Hippo kinase cascades. The expression profiles of these genes in silkworm during embryonic, larval, wandering, pupal and adult stages were analyzed, 14 tissues/organs of the day 3, 5th instar larvae (L5D3) as well. Experimental results showed that the expression of Hippo pathway had some influence on the development of silkworm. In order to find out the mechanism of Hippo pathway affecting silkworm development, BmHpo and BmYki were up-regulated and de-regulated in the cell line of Bombyx mori-BmN-SWU1(NS), and the changes of cell proliferation activity and cell cycle were detected. The distribution of BmYki was detected by immunofluorescence technique. This study provides insights into the genes of Hippo pathway which have a certain effect on somatic development and cell proliferation in silkworm. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. [Notochord cells enhance proliferation and phenotype-keeping of intervertebral disc chondroid cells].

    PubMed

    Zhao, Xianfeng; Liu, Hao; Feng, Ganjun; Deng, Li; Li, Xiuqun; Liang, Tao

    2008-08-01

    To isolate and culture the chondroid cells and notochord cells from New Zealand rabbit immature nucleus pulposus (NP) in monolayer, and to evaluate the responsiveness of rabbit disc-derived chondroid cells to notochord cells with respect to cell proliferation and phenotype. The NP cells were released from the minced immature NP of 6 New Zealand rabbits (4-week-old) by 0.2% collagenase II digestion. The chondroid cells and notochord cells were purified by discontinuous gradient density centrifugation. The chondroid cells were cultured alone (group A) and co-cultured with notochord cells (group B) (1:1), and cell proliferation and phenotype including proteoglycan and collagen II were evaluated. The cells in both groups were observed by the inverted microscope, and the survival rates of the primary and passage cells were detected by toluidine blue staining. The growth curves of the second passage cells in both groups were determined by MTT. Besides, the expressions of proteoglycan and collagen II of the primary and passage cells were examined by toluidine blue and immunocytochemistry staining. The notochord cells and chondroid cells were isolated and purified. With the diameter of 10-15 microm, the notochord cell had abundant intracytoplasmic vesicles, while the chondroid cell, with the diameter of 4-6 microm, had no intracytoplasmic vesicle. The cell survival rate was 89.0%-95.3% in group A and 91.3%-96.3% in group B. There was no significant difference between the same passages in both groups (P > 0.05). The co-cultured cells (group B) increased in cell proliferation compared with the chondroid cells alone (group A) in repeated experiments. The cells in group A reached their logarithmic growth phase after 3-4 days of culture, while the cells in group B did after 2 days of culture. The cell proliferation in group B was more than that in group A after 4-day culture (P < 0.05). The co-cultured cells retained their phenotype for 5 passages, while parallel

  13. D-type cyclins in adult human testis and testicular cancer: relation to cell type, proliferation, differentiation, and malignancy.

    PubMed

    Bartkova, J; Rajpert-de Meyts, E; Skakkebaek, N E; Bartek, J

    1999-04-01

    D-type cyclins are proto-oncogenic components of the 'RB pathway', a G1/S regulatory mechanism centred around the retinoblastoma tumour suppressor (pRB) implicated in key cellular decisions that control cell proliferation, cell-cycle arrest, quiescence, and differentiation. This study focused on immunohistochemical and immunochemical analysis of human adult testis and 32 testicular tumours to examine the differential expression and abundance of cyclins D1, D2, and D3 in relation to cell type, proliferation, differentiation, and malignancy. In normal testis, the cell type-restricted expression patterns were dominated by high levels of cyclin D3 in quiescent Leydig cells and the lack of any D-type cyclin in the germ cells, the latter possibly representing the only example of normal mammalian cells proliferating in the absence of these cyclins. Most carcinoma-in-situ lesions appeared to gain expression of cyclin D2 but not D1 or D3, while the invasive testicular tumours showed variable positivity for cyclins D2 and D3, but rarely D1. An unexpected correlation with differentiation rather than proliferation was found particularly for cyclin D3 in teratomas, a conceptually significant observation confirmed by massive up-regulation of cyclin D3 in the human teratocarcinoma cell line NTera2/D1 induced to differentiate along the neuronal lineage. These results suggest a possible involvement of cyclin D2 in the early stages of testicular oncogenesis and the striking examples of proliferation-independent expression point to potential dual or multiple roles of the D-type cyclins, particularly of cyclin D3. These findings extend current concepts of the biology of the cyclin D subfamily, as well as of the biology and oncopathology of the human adult testis. Apart from practical implications for the assessment of proliferation and oncogenic aberrations in human tissues and tumours, this study may inspire further research into the emerging role of the cyclin D proteins in the

  14. High- and low-LET Radiation-induced Chromosome Aberrations in Human Epithelial Cells Cultured in 3-dimensional Matrices

    NASA Technical Reports Server (NTRS)

    Hada, M.; George K.; Cucinotta, F. A.; Wu, H.

    2008-01-01

    Energetic heavy ions pose a great health risk to astronauts who participate in extended ISS missions and will be an even greater concern for future manned lunar and Mars missions. High-LET heavy ions are particularly effective in causing various biological effects, including cell inactivation, genetic mutations, cataracts and cancer induction. Most of these biological endpoints are closely related to chromosomal damage, which can be utilized as a biomarker for radiation insults. Previously, we had studied low- and high-LET radiation-induced chromosome aberrations in human epithelial cells cultured in 2-dimension (2D) using the multicolor banding fluorescence in situ hybridization (mBAND) technique. However, it has been realized that the biological response to radiation insult in a 2D in vitro cellular environment can differ significantly from the response in 3-dimension (3D) or at the actual tissue level. In this study, we cultured human epithelial cells in 3D to provide a more suitable model for human tissue. Human mammary epithelial cells (CH184B5F5/M10) were grown in Matrigel to form 3D structures, and exposed to Fe-ions at NASA Space Radiation Laboratory (NSRL) at the Brookhaven National Laboratory or 137Cs-gamma radiation source at the University of Texas MD Anderson Cancer Center. After exposure, cells were allowed to repair for 16hr before dissociation and subcultured at low density in 2D. G2 and metaphase chromosomes in the first cell cycle were collected in the first cell cycle after irradiation using a chemical-induced premature chromosome condensation (PCC) technique, and chromosome aberrations were analyzed using mBAND technique. With this technique, individually painted chromosomal bands on one chromosome allowed the identification of interchromosomal aberrations (translocation to unpainted chromosomes) and intrachromosomal aberrations (inversions and deletions within a single painted chromosome). Our data indicate a significant difference in the

  15. Gender differences in the induction of chromosomal aberrations and gene mutations in rodent germ cells

    SciTech Connect

    Adler, Ilse-Dore; Carere, Angelo; Eichenlaub-Ritter, Ursula

    2007-05-15

    Germ cell mutagenicity testing provides experimental data to quantify genetic risk for exposed human populations. The majority of tests are performed with exposure of males, and female data are relatively rare. The reason for this paucity lies in the differences between male and female germ cell biology. Male germ cells are produced throughout reproductive life and all developmental stages can be ascertained by appropriate breeding schemes. In contrast, the female germ cell pool is limited, meiosis begins during embryogenesis and oocytes are arrested over long periods of time until maturation processes start for small numbers of oocytes during the oestrusmore » cycle in mature females. The literature data are reviewed to point out possible gender differences of germ cells to exogenous agents such as chemicals or ionizing radiation. From the limited information, it can be concluded that male germ cells are more sensitive than female germ cells to the induction of chromosomal aberrations and gene mutations. However, exceptions are described which shed doubt on the extrapolation of experimental data from male rodents to the genetic risk of the human population. Furthermore, the female genome may be more sensitive to mutation induction during peri-conceptional stages compared to the male genome of the zygote. With few exceptions, germ cell experiments have been carried out under high acute exposure to optimize the effects and to compensate for the limited sample size in animal experiments. Human exposure to environmental agents, on the other hand, is usually chronic and involves low doses. Under these conditions, gender differences may become apparent that have not been studied so far. Additionally, data are reviewed that suggest a false impression of safety when responses are negative under high acute exposure of male rodents while a mutational response is induced by low chronic exposure. The classical (morphological) germ cell mutation tests are not performed

  16. Role of medullary progenitor cells in epithelial cell migration and proliferation

    PubMed Central

    Chen, Dong; Chen, Zhiyong; Zhang, Yuning; Park, Chanyoung; Al-Omari, Ahmed

    2014-01-01

    This study is aimed at characterizing medullary interstitial progenitor cells and to examine their capacity to induce tubular epithelial cell migration and proliferation. We have isolated a progenitor cell side population from a primary medullary interstitial cell line. We show that the medullary progenitor cells (MPCs) express CD24, CD44, CXCR7, CXCR4, nestin, and PAX7. MPCs are CD34 negative, which indicates that they are not bone marrow-derived stem cells. MPCs survive >50 passages, and when grown in epithelial differentiation medium develop phenotypic characteristics of epithelial cells. Inner medulla collecting duct (IMCD3) cells treated with conditioned medium from MPCs show significantly accelerated cell proliferation and migration. Conditioned medium from PGE2-treated MPCs induce tubule formation in IMCD3 cells grown in 3D Matrigel. Moreover, most of the MPCs express the pericyte marker PDGFR-b. Our study shows that the medullary interstitium harbors a side population of progenitor cells that can differentiate to epithelial cells and can stimulate tubular epithelial cell migration and proliferation. The findings of this study suggest that medullary pericyte/progenitor cells may play a critical role in collecting duct cell injury repair. PMID:24808539

  17. Disorder of G2-M Checkpoint Control in Aniline-Induced Cell Proliferation in Rat Spleen.

    PubMed

    Wang, Jianling; Wang, Gangduo; Khan, M Firoze

    2015-01-01

    Aniline, a toxic aromatic amine, is known to cause hemopoietic toxicity both in humans and animals. Aniline exposure also leads to toxic response in spleen which is characterized by splenomegaly, hyperplasia, fibrosis and the eventual formation of tumors on chronic in vivo exposure. Previously, we have shown that aniline exposure leads to iron overload, oxidative DNA damage, and increased cell proliferation, which could eventually contribute to a tumorigenic response in the spleen. Despite our demonstration that cell proliferation was associated with deregulation of G1 phase cyclins and increased expression of G1 phase cyclin-dependent kinases (CDKs), molecular mechanisms, especially the regulation of G2 phase and contribution of epigenetic mechanisms in aniline-induced splenic cellular proliferation remain largely unclear. This study therefore, mainly focused on the regulation of G2 phase in an animal model preceding a tumorigenic response. Male Sprague-Dawley rats were given aniline (0.5 mmol/kg/day) in drinking water or drinking water only (controls) for 30 days, and expression of G2 phase cyclins, CDK1, CDK inhibitors and miRNAs were measured in the spleen. Aniline treatment resulted in significant increases in cell cycle regulatory proteins, including cyclins A, B and CDK1, particularly phosphor-CDK1, and decreases in CDK inhibitors p21 and p27, which could promote the splenocytes to go through G2/M transition. Our data also showed upregulation of tumor markers Trx-1 and Ref-1 in rats treated with aniline. More importantly, we observed lower expression of miRNAs including Let-7a, miR-15b, miR24, miR-100 and miR-125, and greater expression of CDK inhibitor regulatory miRNAs such as miR-181a, miR-221 and miR-222 in the spleens of aniline-treated animals. Our findings suggest that significant increases in the expression of cyclins, CDK1 and aberrant regulation of miRNAs could lead to an accelerated G2/M transition of the splenocytes, and potentially to a

  18. Disorder of G2-M Checkpoint Control in Aniline-Induced Cell Proliferation in Rat Spleen

    PubMed Central

    Wang, Jianling; Wang, Gangduo; Khan, M. Firoze

    2015-01-01

    Aniline, a toxic aromatic amine, is known to cause hemopoietic toxicity both in humans and animals. Aniline exposure also leads to toxic response in spleen which is characterized by splenomegaly, hyperplasia, fibrosis and the eventual formation of tumors on chronic in vivo exposure. Previously, we have shown that aniline exposure leads to iron overload, oxidative DNA damage, and increased cell proliferation, which could eventually contribute to a tumorigenic response in the spleen. Despite our demonstration that cell proliferation was associated with deregulation of G1 phase cyclins and increased expression of G1 phase cyclin-dependent kinases (CDKs), molecular mechanisms, especially the regulation of G2 phase and contribution of epigenetic mechanisms in aniline-induced splenic cellular proliferation remain largely unclear. This study therefore, mainly focused on the regulation of G2 phase in an animal model preceding a tumorigenic response. Male Sprague-Dawley rats were given aniline (0.5 mmol/kg/day) in drinking water or drinking water only (controls) for 30 days, and expression of G2 phase cyclins, CDK1, CDK inhibitors and miRNAs were measured in the spleen. Aniline treatment resulted in significant increases in cell cycle regulatory proteins, including cyclins A, B and CDK1, particularly phosphor-CDK1, and decreases in CDK inhibitors p21 and p27, which could promote the splenocytes to go through G2/M transition. Our data also showed upregulation of tumor markers Trx-1 and Ref-1 in rats treated with aniline. More importantly, we observed lower expression of miRNAs including Let-7a, miR-15b, miR24, miR-100 and miR-125, and greater expression of CDK inhibitor regulatory miRNAs such as miR-181a, miR-221 and miR-222 in the spleens of aniline-treated animals. Our findings suggest that significant increases in the expression of cyclins, CDK1 and aberrant regulation of miRNAs could lead to an accelerated G2/M transition of the splenocytes, and potentially to a

  19. Nuclear location of tumor suppressor protein maspin inhibits proliferation of breast cancer cells without affecting proliferation of normal epithelial cells

    PubMed Central

    2014-01-01

    Background Maspin, which is classified as a tumor suppressor protein, is downregulated in many types of cancer. Several studies have suggested potential anti-proliferative activity of maspin as well as sensitizing activity of maspin for therapeutic cytotoxic agents in breast cancer tissue culture and animal models. All of the experimental data gathered so far have been based on studies with maspin localized cytoplasmically, while maspin in breast cancer tumor cells may be located in the cytoplasm, nucleus or both. In this study, the effect of maspin cytoplasmic and nuclear location and expression level on breast cancer proliferation and patient survival was studied. Methods Tissue sections from 166 patients with invasive ductal breast cancer were stained by immunohistochemistry for maspin and Ki-67 protein. The localization and expression level of maspin were correlated with estimated patient overall survival and percent of Ki-67-positive cells. In further studies, we created constructs for transient transfection of maspin into breast cancer cells with targeted cytoplasmic and nuclear location. We analyzed the effect of maspin location in normal epithelial cell line MCF10A and three breast cancer cell lines - MCF-7, MDA-MB-231 and SKBR-3 - by immunofluorescence and proliferation assay. Results We observed a strong positive correlation between moderate and high nuclear maspin level and survival of patients. Moreover, a statistically significant negative relationship was observed between nuclear maspin and Ki-67 expression in patients with invasive ductal breast cancer. Spearman’s correlation analysis showed a negative correlation between level of maspin localized in nucleus and percentage of Ki-67 positive cells. No such differences were observed in cells with cytoplasmic maspin. We found a strong correlation between nuclear maspin and loss of Ki-67 protein in breast cancer cell lines, while there was no effect in normal epithelial cells from breast. The anti

  20. M-Band Analysis of Chromosome Aberrations in Human Epithelial Cells Induced By Low- and High-Let Radiations

    NASA Technical Reports Server (NTRS)

    Hada, M.; Gersey, B.; Saganti, P. B.; Wilkins, R.; Gonda, S. R.; Cucinotta, F. A.; Wu, H.

    2007-01-01

    Energetic primary and secondary particles pose a health risk to astronauts in extended ISS and future Lunar and Mars missions. High-LET radiation is much more effective than low-LET radiation in the induction of various biological effects, including cell inactivation, genetic mutations, cataracts and cancer. Most of these biological endpoints are closely correlated to chromosomal damage, which can be utilized as a biomarker for radiation insult. In this study, human epithelial cells were exposed in vitro to gamma rays, 1 GeV/nucleon Fe ions and secondary neutrons whose spectrum is similar to that measured inside the Space Station. Chromosomes were condensed using a premature chromosome condensation technique and chromosome aberrations were analyzed with the multi-color banding (mBAND) technique. With this technique, individually painted chromosomal bands on one chromosome allowed the identification of both interchromosomal (translocation to unpainted chromosomes) and intrachromosomal aberrations (inversions and deletions within a single painted chromosome). Results of the study confirmed the observation of higher incidence of inversions for high-LET irradiation. However, detailed analysis of the inversion type revealed that all of the three radiation types in the study induced a low incidence of simple inversions. Half of the inversions observed in the low-LET irradiated samples were accompanied by other types of intrachromosome aberrations, but few inversions were accompanied by interchromosome aberrations. In contrast, Fe ions induced a significant fraction of inversions that involved complex rearrangements of both the inter- and intrachromosome exchanges.

  1. Butyl benzyl phthalate suppresses the ATP-induced cell proliferation in human osteosarcoma HOS cells

    SciTech Connect

    Liu, P.-S., E-mail: pslediting@mail.scu.edu.t; Chen, C.-Y.

    2010-05-01

    Butyl benzyl phthalate (BBP), an endocrine disruptor present in the environment, exerts its genomic effects via intracellular steroid receptors and elicits non-genomic effects by interfering with membrane ion-channel receptors. We previously found that BBP blocks the calcium signaling coupled with P2X receptors in PC12 cells (Liu and Chen, 2006). Osteoblast P2X receptors were recently reported to play a role in cell proliferation and bone remodeling. In this present study, the effects of BBP on ATP-induced responses were investigated in human osteosarcoma HOS cells. These receptors mRNA had been detected, named P2X4, P2X7, P2Y2, P2Y4, P2Y5, P2Y9, and P2Y11, in humanmore » osteosarcoma HOS cells by RT-PCR. The enhancement of cell proliferation and the decrease of cytoviability had both been shown to be coupled to stimulation via different concentrations of ATP. BBP suppressed the ATP-induced calcium influx (mainly coupled with P2X) and cell proliferation but not the ATP-induced intracellular calcium release (mainly coupled with P2Y) and cytotoxicity in human osteosarcoma HOS cells. Suramin, a common P2 receptor's antagonist, blocked the ATP-induced calcium signaling, cell proliferation, and cytotoxicity. We suggest that P2X is mainly responsible for cell proliferation, and P2Y might be partially responsible for the observed cytotoxicity. BBP suppressed the calcium signaling coupled with P2X, suppressing cell proliferation. Since the importance of P2X receptors during bone metastasis has recently become apparent, the possible toxic risk of environmental BBP during bone remodeling is a public problem of concern.« less

  2. Paclitaxel Impairs Adipose Stem Cell Proliferation and Differentiation

    PubMed Central

    Choron, Rachel L.; Chang, Shaohua; Khan, Sophia; Villalobos, Miguel A.; Zhang, Ping; Carpenter, Jeffrey P.; Tulenko, Thomas N.; Liu, Yuan

    2015-01-01

    BACKGROUND Cancer patients with chemotherapy-induced immunosuppression have poor surgical site wound healing. Prior literature supports the use of human adipose-derived stem cell (hASC) lipoinjection to improve wound healing. It has been established multipotent hASCs facilitate neovascularization, accelerated epithelialization, and wound closure in animal models. While hASC wound therapy may benefit surgical cancer patients, the chemotherapeutic effects on hASCs are unknown. We hypothesized Paclitaxel, a chemotherapeutic agent, impairs hASC growth, multipotency, and induces apoptosis. METHODS hASCs were isolated and harvested from consented, chemotherapy and radiation naïve patients. Growth curves, MTT, and EdU assays measured cytotoxicity and proliferation. Oil-Red-O stain, Alazarin-Red stain, Matrigel tube-formation assay, and qPCR analyzed hASC differentiation. Annexin V assay measured apoptosis. Immunostaining and Western blot determined TNF-α expression. RESULTS hASCs were selectively more sensitive to Paclitaxel (0.01μM–30μM) than fibroblasts (p<0.05). After 12 days, Paclitaxel caused hASC growth arrest whereas control hASCs proliferated (p=0.006). Paclitaxel caused an 80.6% reduction in new DNA synthesis (p<0.001). Paclitaxel severely inhibited endothelial differentiation and capillary-like tube formation. Differentiation markers LPL (adipogenic), alkaline phosphatase (osteogenic), CD31 and vWF (endothelial) were significantly decreased (all: p<0.05) confirming Paclitaxel impaired differentiation. Paclitaxel was also found to induce apoptosis and TNF-α was up-regulated in Paclitaxel-treated hASCs (p<0.001). CONCLUSION Paclitaxel is more cytotoxic to hASCs than fibroblasts. Paclitaxel inhibits hASC proliferation, differentiation, and induces apoptosis, possibly through the TNF-α pathway. Paclitaxel’s severe inhibition of endothelial differentiation indicates neovascularization disruption, possibly causing poor wound healing in cancer patients

  3. Overexpression or absence of calretinin in mouse primary mesothelial cells inversely affects proliferation and cell migration.

    PubMed

    Blum, Walter; Pecze, László; Felley-Bosco, Emanuela; Schwaller, Beat

    2015-12-22

    The Ca(2+)-binding protein calretinin is currently used as a positive marker for identifying epithelioid malignant mesothelioma (MM) and reactive mesothelium, but calretinin's likely role in mesotheliomagenesis remains unclear. Calretinin protects immortalized mesothelial cells in vitro from asbestos-induced cytotoxicity and thus might be implicated in mesothelioma formation. To further investigate calretinin's putative role in the early steps of MM generation, primary mesothelial cells from calretinin knockout (CR-/-) and wildtype (WT) mice were compared. Primary mouse mesothelial cells from WT and CR-/- mice were investigated with respect to morphology, marker proteins, proliferation, cell cycle parameters and mobility in vitro. Overexpression of calretinin or a nuclear-targeted variant was achieved by a lentiviral expression system. CR-/- mice have a normal mesothelium and no striking morphological abnormalities compared to WT animals were noted. Primary mouse mesothelial cells from both genotypes show a typical "cobblestone-like" morphology and express mesothelial markers including mesothelin. In cells from CR-/- mice in vitro, we observed more giant cells and a significantly decreased proliferation rate. Up-regulation of calretinin in mesothelial cells of both genotypes increases the proliferation rate and induces a cobblestone-like epithelial morphology. The length of the S/G2/M phase is unchanged, however the G1 phase is clearly prolonged in CR-/- cells. They are also much slower to close a scratch in a confluent cell layer (2D-wound assay). In addition to a change in cell morphology, an increase in proliferation and mobility is observed, if calretinin overexpression is targeted to the nucleus. Thus, both calretinin and nuclear-targeted calretinin increase mesothelial cell proliferation and consequently, speed up the scratch-closure time. The increased rate of scratch closure in WT cells is the result of two processes: an increased proliferation rate and

  4. Psoriatic T cells reduce epidermal turnover time and affect cell proliferation contributed from differential gene expression.

    PubMed

    Li, Junqin; Li, Xinhua; Hou, Ruixia; Liu, Ruifeng; Zhao, Xincheng; Dong, Feng; Wang, Chunfang; Yin, Guohua; Zhang, Kaiming

    2015-09-01

    Psoriasis is mediated primarily by T cells, which reduce epidermal turnover time and affect keratinocyte proliferation. We aimed to identify differentially expressed genes (DEG) in T cells from normal, five pairs of monozygotic twins concordant or discordant for psoriasis, to determine whether these DEG may account for the influence to epidermal turnover time and keratinocyte proliferation. The impact of T cells on keratinocyte proliferation and epidermal turnover time were investigated separately by immunohistochemistry and cultured with (3) H-TdR. mRNA expression patterns were investigated by RNA sequencing and verified by real-time reverse transcription polymerase chain reaction. After co-culture with psoriatic T cells, the expression of Ki-67, c-Myc and p53 increased, while expression of Bcl-2 and epidermal turnover time decreased. There were 14 DEG which were found to participate in the regulation of cell proliferation or differentiation. Psoriatic T cells exhibited the ability to decrease epidermal turnover time and affect keratinocyte proliferation because of the differential expression of PPIL1, HSPH1, SENP3, NUP54, FABP5, PLEKHG3, SLC9A9 and CHCHD4. © 2015 Japanese Dermatological Association.

  5. miR-152 regulated glioma cell proliferation and apoptosis via Runx2 mediated by DNMT1.

    PubMed

    Zhang, Peng; Sun, Hongwei; Yang, Bo; Luo, Wenzheng; Liu, Zengjin; Wang, Junkuan; Zuo, Yuchao

    2017-08-01

    Aberrant DNA methylation is associated with tumor onset and progression. Study has verified that the DNA methylation of miR-152 was mediated in many tumors, but whether it involved in glioblastomas was still unclear. This study enrolled 20 patients with glioma to analyze the expression pattern of miR-152. Real-time PCR and western blot were used to detect the mRNA or protein expression level, respectively. The relationship between miR-152 and runx2 was detected by Luciferase reporter assay. The methylation level of miR-152 was determined by methylation-specific PCR. Cell proliferation and apoptosis were detected by MTT and Annexin-FITC/PI assay. The expression of miR-152 was down-regulated while the expression of DNMT1 was up-regulated in both glioma tissue and cell lines. MiR-152 was hypermethylated and its expression was negatively correlated with DNMT in glioma cell lines. DNMT1 knockdown promoted the expression of miR-152, however, DNMT1 overexpression suppressed the expression of miR-152. MiR-152 overexpression promoted glioma cell apoptosis while miR-152 knockdown promoted cell proliferation. MiR-152 targets Runx2 to regulate its expression, Runx2 overexpression abolished the effects of miR-152 overexpression. MiR-152 regulated cell proliferation and apoptosis of glioma mediated by Runx2, while the mechanism of down regulated miR-152 in glioma tissues and cells was its hypermethylation. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  6. [Regulatory T cells inhibit proliferation of mouse lymphoma cell line EL4 in vitro].

    PubMed

    Zhang, Chen; Kong, Yan; Guo, Jun; Ying, Zhi-Tao; Yuan, Zhi-Hong; Zhang, Yun-Tao; Zheng, Wen; Song, Yu-Qin; Li, Ping-Ping; Zhu, Jun

    2010-10-01

    This study was aimed to investigate the effect of regulatory T (Treg) cells on the T cell lymphoma EL4 cells and its mechanism in vitro. C57BL/6 mouse Treg cells were isolated by magnetic cell sorting (MACS). The purity of Treg cells and their expression of Foxp3 were identified by flow cytometry (FCM) and PT-PCR respectively. The suppression of Treg cells on EL4 cells was detected by 3H-TdR method. At the same time, enzyme-linked immunosorbent assay (ELISA) was used to detect the secretion of cytokine TGF-β1 and IL-10. The results showed that CD4+CD25+ T cells could be successfully isolated by MACS with the purity reaching 94.52% and the expression of Foxp3 reaching 84.72%. After sorting, the expression of Foxp3 mRNA could be detected by RT-PCR. 3H-TdR assay confirmed that regulatory T cells could suppress the proliferation of EL4 cells with or without antigen presenting cells (APC) or dendritic cells (DC), APC or DC might effectively enhance the suppression. In addition, DC alone also suppressed the proliferation. TGF-β1 and IL-10 could be detected in the supernatant by ELISA. It is concluded that the Treg cells can obviously suppress the proliferation of T cell lymphoma cells in vitro, APC or DC can enhance this suppressive effect, while the DC alone also can suppress the proliferation of EL4 cells, the TGF-β1 and IL-10 cytokine pathway may be one of the mechanisms of suppression.

  7. Evaluation of chromosomal aberrations induced by 188Re-dendrimer nanosystem on B16f1 melanoma cells.

    PubMed

    Tassano, Marcos; Oddone, Natalia; Fernández, Marcelo; Porcal, Williams; García, María Fernanda; Martínez-López, Wilner; Benech, Juan Claudio; Cabral, Pablo

    2018-06-19

    To study the rhenium-188 labeling of polyamidoamine (PAMAM) generation 4 (G4) dendrimer and its evaluation on biodistribution and chromosomal aberrations in melanoma cells induced by ionizing radiation as potential treatment agent. Dendrimers were first conjugated with Suc-HYNIC (succinimidyl 6-hydrazinopyridine-3-carboxylic acid hydrochloride). Dendrimer-HYNIC was then incubated with 188 ReO 4 - . Biodistribution was performed administrating 188 Re-dendrimer to normal (NM) or melanoma-bearing mice (MBM). Chromosome aberration test was conducted in order to measure treatment capacity of 188 Re-dendrimer in melanoma cells. Radiolabeling yield of dendrimer was approx. 70%. Biodistribution studies in NM showed blood clearance with hepatic and renal depuration. MBM showed a similar pattern of biodistribution with tumor uptake of 6% of injected dose. Aberrant metaphases quantified in control cells were 7%, increasing to 29.5% in cells treated with 15μCi (0.555 MBq) of 188 Re-dendrimer for 24 h. 188 Re-dendrimer can produce double-stranded breaks in DNA induced by ionizing radiation in melanoma cells in vitro.

  8. Extracellular Calcium Has Multiple Targets to Control Cell Proliferation.

    PubMed

    Capiod, Thierry

    2016-01-01

    Calcium channels and the two G-protein coupled receptors sensing extracellular calcium, calcium-sensing receptor (CaSR) and GPRC6a, are the two main means by which extracellular calcium can signal to cells and regulate many cellular processes including cell proliferation, migration and invasion of tumoral cells. Many intracellular signaling pathways are sensitive to cytosolic calcium rises and conversely intracellular signaling pathways can modulate calcium channel expression and activity. Calcium channels are undoubtedly involved in the former while the CaSR and GPRC6a are most likely to interfere with the latter. As for neurotransmitters, calcium ions use plasma membrane channels and GPCR to trigger cytosolic free calcium concentration rises and intracellular signaling and regulatory pathways activation. Calcium sensing GPCR, CaSR and GPRC6a, allow a supplemental degree of control and as for metabotropic receptors, they not only modulate calcium channel expression but they may also control calcium-dependent K+ channels. The multiplicity of intracellular signaling pathways involved, their sensitivity to local and global intracellular calcium increase and to CaSR and GPRC6a stimulation, the presence of membrane signalplex, all this confers the cells the plasticity they need to convert the effects of extracellular calcium into complex physiological responses and therefore determine their fate.

  9. Mesenchymal stem cells induce epithelial proliferation within the inflamed stomach.

    PubMed

    Donnelly, Jessica M; Engevik, Amy; Feng, Rui; Xiao, Chang; Boivin, Gregory P; Li, Jing; Houghton, JeanMarie; Zavros, Yana

    2014-06-15

    Bone marrow-derived mesenchymal stem cells (MSCs) sustain cancer cells by creating a microenvironment favorable for tumor growth. In particular, MSCs have been implicated in gastric cancer development. There is extensive evidence suggesting that Hedgehog signaling regulates tumor growth. However, very little is known regarding the precise roles of Hedgehog signaling and MSCs in tumor development within the stomach. The current study tests that hypothesis that Sonic Hedgehog (Shh), secreted from MSCs, provides a proliferative stimulus for the gastric epithelium in the presence of inflammation. Red fluorescent protein-expressing MSCs transformed in vitro (stMSCs) were transduced with lentiviral constructs containing a vector control (stMSC(vect)) or short hairpin RNA (shRNA) targeting the Shh gene (stMSC(ShhKO)). Gastric submucosal transplantation of wild-type MSCs (wtMSCs), wild-type MSCs overexpressing Shh (wtMSC(Shh)), stMSC(vect), or stMSC(ShhKO) cells in C57BL/6 control (BL/6) or gastrin-deficient (GKO) mice was performed and mice analyzed 30 and 60 days posttransplantation. Compared with BL/6 mice transplanted with wtMSC(Shh) and stMSC(vect) cells, inflamed GKO mice developed aggressive gastric tumors. Tumor development was not observed in mouse stomachs transplanted with wtMSC or stMSC(ShhKO) cells. Compared with stMSC(ShhKO)-transplanted mice, within the inflamed GKO mouse stomach, Shh-expressing stMSC(vect)- and wtMSC(Shh)-induced proliferation of CD44-positive cells. CD44-positive cells clustered in gland-like structures within the tumor stroma and were positive for Patched (Ptch) expression. We conclude that Shh, secreted from MSCs, provides a proliferative stimulus for the gastric epithelium that is associated with tumor development, a response that is sustained by chronic inflammation. Copyright © 2014 the American Physiological Society.

  10. Mesenchymal stem cells induce epithelial proliferation within the inflamed stomach

    PubMed Central

    Donnelly, Jessica M.; Engevik, Amy; Feng, Rui; Xiao, Chang; Boivin, Gregory P.; Li, Jing; Houghton, JeanMarie

    2014-01-01

    Bone marrow-derived mesenchymal stem cells (MSCs) sustain cancer cells by creating a microenvironment favorable for tumor growth. In particular, MSCs have been implicated in gastric cancer development. There is extensive evidence suggesting that Hedgehog signaling regulates tumor growth. However, very little is known regarding the precise roles of Hedgehog signaling and MSCs in tumor development within the stomach. The current study tests that hypothesis that Sonic Hedgehog (Shh), secreted from MSCs, provides a proliferative stimulus for the gastric epithelium in the presence of inflammation. Red fluorescent protein-expressing MSCs transformed in vitro (stMSCs) were transduced with lentiviral constructs containing a vector control (stMSCvect) or short hairpin RNA (shRNA) targeting the Shh gene (stMSCShhKO). Gastric submucosal transplantation of wild-type MSCs (wtMSCs), wild-type MSCs overexpressing Shh (wtMSCShh), stMSCvect, or stMSCShhKO cells in C57BL/6 control (BL/6) or gastrin-deficient (GKO) mice was performed and mice analyzed 30 and 60 days posttransplantation. Compared with BL/6 mice transplanted with wtMSCShh and stMSCvect cells, inflamed GKO mice developed aggressive gastric tumors. Tumor development was not observed in mouse stomachs transplanted with wtMSC or stMSCShhKO cells. Compared with stMSCShhKO-transplanted mice, within the inflamed GKO mouse stomach, Shh-expressing stMSCvect- and wtMSCShh-induced proliferation of CD44-positive cells. CD44-positive cells clustered in gland-like structures within the tumor stroma and were positive for Patched (Ptch) expression. We conclude that Shh, secreted from MSCs, provides a proliferative stimulus for the gastric epithelium that is associated with tumor development, a response that is sustained by chronic inflammation. PMID:24789207

  11. Combined aspirin and apatinib treatment suppresses gastric cancer cell proliferation.

    PubMed

    Zhang, Wei; Tan, Yongsheng; Ma, Heping

    2017-11-01

    Gastric cancer (GC), one of the types of tumor most prone to malignancy, is characterized by high lethality. Numerous molecular mediators of GC have been identified, including transcription factors, signaling molecules and non-coding RNAs. Recently, inhibition of angiogenesis has emerged as a potential strategy for GC therapy. In the present study, the levels of vascular endothelial growth factor (VEGF), peroxisome proliferator-activated receptor-α (PPARα) and miR-21 in GC patients and individuals without cancer, and the correlation between VEGF and miR-21, and PPARα and miR-21 expression were analyzed. In addition, the GC MKN45 cell line was treated with apatinib (a tyrosine kinase inhibitor) and aspirin (an activator of the transcription factor, PPARα) to investigate the effects of these compounds on tumorigenesis. Furthermore, the present study attempted to elucidate the molecular mechanisms of alteration of GC tumorigenesis by aspirin and apatinib. The results of the current study demonstrated that there was a higher expression of VEGF and miR-21 in GC tissues compared with that in morphologically adjacent normal tissues whereas PPARα expression was decreased. These results were confirmed in vitro , as treatment of MKN45 cells with VEGF resulted in a significant increase in miR-21 expression and a significant reduction in PPARα protein expression. Furthermore, the inhibitory effects of VEGF on PPARα mRNA and protein expression were demonstrated to be mediated by miR-21. Suppression of PPARα protein expression attenuated the inhibitory effects of miR-21 on the level of PPARα mRNA, thereby enhancing tumorigenesis in gastric cancer. Treatment of MKN45 cells with aspirin reduced the levels of phosphorylated AKT by activating PPARα, whereas treatment with apatinib inhibited the phosphorylation of vascular endothelial growth factor receptor 2 and phosphoinositide-3 kinase in MKN45 cells. Finally, treatment of MKN45 cells with apatinib and aspirin suppressed

  12. Protease-activated receptor 2 modulates proliferation and invasion of oral squamous cell carcinoma cells.

    PubMed

    Al-Eryani, Kamal; Cheng, Jun; Abé, Tatsuya; Maruyama, Satoshi; Yamazaki, Manabu; Babkair, Hamzah; Essa, Ahmed; Saku, Takashi

    2015-07-01

    Based on our previous finding that protease-activated receptor 2 (PAR-2) regulates hemophagocytosis of oral squamous cell carcinoma (SCC) cells, which induces their heme oxygenase 1-dependent keratinization, we have formulated a hypothesis that PAR-2 functions in wider activities of SCC cells. To confirm this hypothesis, we investigated immunohistochemical profiles of PAR-2 in oral SCC tissues and its functional roles in cell proliferation and invasion in SCC cells in culture. The PAR-2 expression modes were determined in 48 surgical tissue specimens of oral SCC. Using oral SCC-derived cell systems, we determined both gene and protein expression levels of PAR-2. SCC cell proliferation and invasive properties were also examined in conditions in which PAR-2 was activated by the synthetic peptide SLIGRL. PAR-2 was immunolocalized in oral SCC and carcinoma in situ cells, especially in those on the periphery of carcinoma cell foci (100% of cases), but not in normal oral epithelia. Its expression at both gene and protein levels was confirmed in 3 oral SCC cell lines including ZK-1. Activation of PAR-2 induced ZK-1 cell proliferation in a dose-dependent manner. PAR-2-activated ZK-1 cells invaded faster than nonactivated ones. The expression of PAR-2 is specific to oral malignancies, and PAR-2 regulates the growth and invasion of oral SCC cells. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Transient inhibition of cell proliferation does not compromise self-renewal of mouse embryonic stem cells.

    PubMed

    Wang, Ruoxing; Guo, Yan-Lin

    2012-10-01

    Embryonic stem cells (ESCs) have unlimited capacity for self-renewal and can differentiate into various cell types when induced. They also have an unusual cell cycle control mechanism driven by constitutively active cyclin dependent kinases (Cdks). In mouse ESCs (mESCs). It is proposed that the rapid cell proliferation could be a necessary part of mechanisms that maintain mESC self-renewal and pluripotency, but this hypothesis is not in line with the finding in human ESCs (hESCs) that the length of the cell cycle is similar to differentiated cells. Therefore, whether rapid cell proliferation is essential for the maintenance of mESC state remains unclear. We provide insight into this uncertainty through chemical intervention of mESC cell cycle. We report here that inhibition of Cdks with olomoucine II can dramatically slow down cell proliferation of mESCs with concurrent down-regulation of cyclin A, B and E, and the activation of the Rb pathway. However, mESCs display can recover upon the removal of olomoucine II and are able to resume normal cell proliferation without losing self-renewal and pluripotency, as demonstrated by the expression of ESC markers, colony formation, embryoid body formation, and induced differentiation. We provide a mechanistic explanation for these observations by demonstrating that Oct4 and Nanog, two major transcription factors that play critical roles in the maintenance of ESC properties, are up-regulated via de novo protein synthesis when the cells are exposed to olomoucine II. Together, our data suggest that short-term inhibition of cell proliferation does not compromise the basic properties of mESCs. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Mutagenicity and antimutagenicity of Baccharis dracunculifolia extract in chromosomal aberration assays in Chinese hamster ovary cells.

    PubMed

    Munari, Carla Carolina; Resende, Flávia Aparecida; Alves, Jacqueline Morais; de Sousa, João Paulo; Bastos, Jairo Kenupp; Tavares, Denise Crispim

    2008-09-01

    Baccharis dracunculifolia De Candole (Asteraceae), a native plant from the Brazilian "cerrado", is widely used in folk medicine as an anti-inflammatory agent and for the treatment of gastrointestinal diseases. B. dracunculifolia has been described as the most important plant source of propolis in southeastern Brazil, which is called green propolis due to its color. The aim of the present study was to evaluate the mutagenic and antimutagenic effects of the ethyl acetate extract of B. dracunculifolia leaves (Bd-EAE) on Chinese hamster ovary cells. On one hand, the results showed a significant increase in the frequencies of chromosome aberrations at the highest Bd-EAE concentration tested (100 microg/mL). On the other hand, the lowest Bd-EAE concentration tested (12.5 micro/mL) significantly reduced the chromosome damage induced by the chemotherapeutic agent doxorubicin. The present results indicate that Bd-EAE has the characteristics of a so-called Janus compound, that is, Bd-EAE is mutagenic at higher concentrations, whereas it displays a chemopreventive effect on doxorubicin-induced mutagenicity at lower concentrations. The constituents of B. dracunculifolia responsible for its mutagenic and antimutagenic effects are probably flavonoids and phenylpropanoids, since these compounds can act either as pro-oxidants or as free radical scavengers depending on their concentration.

  15. Cell Size Control and a Cell-intrinsic Maturation Program in Proliferating Oligodendrocyte Precursor Cells

    PubMed Central

    Gao, Fen-Biao; Raff, Martin

    1997-01-01

    We have used clonal analysis and time-lapse video recording to study the proliferative behavior of purified oligodendrocyte precursor cells isolated from the perinatal rat optic nerve growing in serum-free cultures. First, we show that the cell cycle time of precursor cells decreases with increasing concentrations of PDGF, the main mitogen for these cells, suggesting that PDGF levels may regulate the cell cycle time during development. Second, we show that precursor cells isolated from embryonic day 18 (E18) nerves differ from precursor cells isolated from postnatal day 7 (P7) or P14 nerves in a number of ways: they have a simpler morphology, and they divide faster and longer before they stop dividing and differentiate into postmitotic oligodendrocytes. Third, we show that purified E18 precursor cells proliferating in culture progressively change their properties to resemble postnatal cells, suggesting that progressive maturation is an intrinsic property of the precursors. Finally, we show that precursor cells, especially mature ones, sometimes divide unequally, such that one daughter cell is larger than the other; in each of these cases the larger daughter cell divides well before the smaller one, suggesting that the precursor cells, just like single-celled eucaryotes, have to reach a threshold size before they can divide. These and other findings raise the possibility that such stochastic unequal divisions, rather than the stochastic events occurring in G1 proposed by “transition probability” models, may explain the random variability of cell cycle times seen within clonal cell lines in culture. PMID:9298991

  16. 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.

  17. Folic Acid supplementation stimulates notch signaling and cell proliferation in embryonic neural stem cells.

    PubMed

    Liu, Huan; Huang, Guo-Wei; Zhang, Xu-Mei; Ren, Da-Lin; X Wilson, John

    2010-09-01

    The present study investigated the effect of folic acid supplementation on the Notch signaling pathway and cell proliferation in rat embryonic neural stem cells (NSCs). The NSCs were isolated from E14-16 rat brain and grown as neurospheres in serum-free suspension culture. Individual cultures were assigned to one of 3 treatment groups that differed according to the concentration of folic acid in the medium: Control (baseline folic acid concentration of 4 mg/l), low folic acid supplementation (4 mg/l above baseline, Folate-L) and high folic acid supplementation (40 mg/l above baseline, Folate-H). NSCs were identified by their expression of immunoreactive nestin and proliferating cells by incorporation of 5'bromo-2'deoxyuridine. Cell proliferation was also assessed by methyl thiazolyl tetrazolium assay. Notch signaling was analyzed by real-time PCR and western blot analyses of the expression of Notch1 and hairy and enhancer of split 5 (Hes5). Supplementation of NSCs with folic acid increased the mRNA and protein expression levels of Notch1 and Hes5. Folic acid supplementation also stimulated NSC proliferation dose-dependently. Embryonic NSCs respond to folic acid supplementation with increased Notch signaling and cell proliferation. This mechanism may mediate the effects of folic acid supplementation on neurogenesis in the embryonic nervous system.

  18. Y-27632 Increases Sensitivity of PANC-1 Cells to EGCG in Regulating Cell Proliferation and Migration.

    PubMed

    Liu, Xing; Bi, Yongyi

    2016-10-03

    BACKGROUND The study aimed to investigate the inhibitory effect of (1R,4r)-4-((R)-1-aminoethyl)-N-(pyridin-4-yl) cyclohexanecarboxamide (Y-27632) and (-)-epigallocatechin-3-gallate (EGCG) on the proliferation and migration of PANC-1 cells. EGCG, found in green tea, has been previously shown to be one of the most abundant and powerful catechins in cancer prevention and treatment. Y-27632, a selective inhibitor of rho-associated protein kinase 1, is widely used in treating cardiovascular disease, inflammation, and cancer. MATERIAL AND METHODS PANC-1 cells, maintained in Dulbecco's Modified Eagle's Medium, were treated with dimethyl sulfoxide (control) as well as different concentrations (20, 40, 60, and 80 μg/mL) of EGCG for 48 h. In addition, PANC-1 cells were treated separately with 60 μg/mL EGCG, 20 μM Y-27632, and EGCG combined with Y-27632 (60 μg/mL EGCG + 20 μM Y-27632) for 48 h. The effect of EGCG and Y-27632 on the proliferation and migration of PANC-1 cells was evaluated using Cell Counting Kit-8 and transwell migration assays. The expression of peroxisome proliferator-activated receptor alpha (PPARα) and Caspase-3 mRNA was determined by Quantitative real-time polymerase chain reaction (RT-qPCR). RESULTS EGCG (20-80 μg/mL) inhibited cell viability in a dose-dependent manner. Y-27632 enhanced the sensitivity of PANC-1 cells to EGCG (by increasing the expression of PPARa and Caspase-3 mRNA) and suppressed cell proliferation. PANC-1 cell migration was inhibited by treatment with a combination of EGCG and Y-27632. CONCLUSIONS Y-27632 increases the sensitivity of PANC-1 cells to EGCG in regulating cell proliferation and migration, which is likely to be related to the expression of PPARa mRNA and Caspase-3 mRNA.

  19. Exercise reduces inflammation and cell proliferation in rat colon carcinogenesis.

    PubMed

    Demarzo, Marcelo Marcos Piva; Martins, Lisandra Vanessa; Fernandes, Cleverson Rodrigues; Herrero, Fábio Augusto; Perez, Sérgio Eduardo de Andrade; Turatti, Aline; Garcia, Sérgio Britto

    2008-04-01

    There is evidence that the risk of colon cancer is reduced by appropriate levels of physical exercise. Nevertheless, the mechanisms involved in this protective effect of exercise remain largely unknown. Inflammation is emerging as a unifying link between a range of environment exposures and neoplastic risk. The carcinogen dimethyl-hydrazine (DMH) induces an increase in epithelial cell proliferation and in the expression of the inflammation-related enzyme cyclooxigenase-2 (COX-2) in the colon of rats. Our aim was to verify whether these events could be attenuated by exercise. Four groups of eight Wistar rats were used in the experiment. The groups G1 and G3 were sedentary (controls), and the groups G2 and G4 were submitted to 8 wk of swimming training, 5 d.wk. The groups G3 and G4 were given subcutaneous injections of DMH immediately after the exercise protocols. Fifteen days after the neoplasic induction, the rats were sacrificed and the colon was processed for histological examination and immunohistochemistry staining of proliferating cell nuclear antigen (PCNA) and COX-2. We found a significant increase in the PCNA-labeling index in both DMH-treated groups of rats. However, this increase was significantly attenuated in the training group G4 (P < 0.01). Similar results were observed in relation to the COX-2 expression. From our findings, we conclude that exercise training exerts remarkable antiproliferative and antiinflammatory effects in the rat colonic mucosa, suggesting that this may be an important mechanism to explain how exercise protects against colonic cancer.

  20. Osthole induces apoptosis, suppresses cell-cycle progression and proliferation of cancer cells.

    PubMed

    Jarząb, Agata; Grabarska, Aneta; Kiełbus, Michał; Jeleniewicz, Witold; Dmoszyńska-Graniczka, Magdalena; Skalicka-Woźniak, Krystyna; Sieniawska, Elwira; Polberg, Krzysztof; Stepulak, Andrzej

    2014-11-01

    The aim of the present study was to determine the effects of osthole on cell proliferation and viability, cell-cycle progression and induction of apoptosis in human laryngeal cancer RK33 and human medulloblastoma TE671 cell lines. Cell viability was measured by means of the MTT method and cell proliferation by the 5-bromo-2-deoxyuridine (BrdU) incorporation assay. Cell-cycle progression was determined by flow cytometry, and induction of apoptosis by release of oligonucleosomes to the cytosol. The gene expression was estimated by a quantitative polymerase chain reaction (qPCR) method. High-performance counter-current chromatography (HPCCC) was applied for isolation of osthole from fruits of Mutellina purpurea. Osthole decreased proliferation and cell viability of cancer cells in a dose-dependent manner. The tested compound induced apoptosis, increased the cell numbers in G1 and decreased cell number in S/G2 phases of the cell cycle, differentially regulating CDKN1A and TP53 gene expression depending on cancer cell type. Osthole could be considered as a potential compound for cancer therapy and chemoprevention. Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  1. Low power laser irradiation stimulates cell proliferation via proliferating cell nuclear antigen and Ki-67 expression during tissue repair

    NASA Astrophysics Data System (ADS)

    Prabhu, Vijendra; Rao, Bola Sadashiva Satish; Mahato, Krishna Kishore

    2015-03-01

    Low power laser irradiation (LPLI) is becoming an increasingly popular and fast growing therapeutic modality in dermatology to treat various ailments without any reported side effects. In the present study an attempt was made to investigate the proliferative potential of red laser light during tissue repair in Swiss albino mice. To this end, full thickness excisional wounds of diameter 15 mm created on mice were exposed to single dose of Helium-Neon laser (632.8 nm; 7 mW; 4.02 mWcm-2; Linear polarization) at 2 Jcm-2 and 10 Jcm-2 along with un-illuminated controls. The granulation tissues from all the respective experimental groups were harvested on day 10 post-wounding following euthanization. Subsequently, tissue regeneration potential of these laser doses under study were evaluated by monitoring proliferating cell nuclear antigen and Ki-67 following the laser treatment and comparing it with the un-illuminated controls. The percentages of Ki-67 or PCNA positive cells were determined by counting positive nuclei (Ki-67/PCNA) and total nuclei in five random fields per tissue sections. Animal wounds treated with single exposure of the 2 Jcm-2 indicated significant elevation in PCNA (P<0.01) and Ki-67 (P<0.05 compared to un-illuminated control and P<0.01 compared to 10 Jcm-2) expression as compared to other tested experimental groups as evidenced by the microscopy results in the study. In summary, the findings of the present study have clearly demonstrated the regulation of cell proliferation by LPLI via PCNA and Ki-67 expression during tissue regeneration.

  2. 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.

  3. Overexpression of caspase 7 is ERα dependent to affect proliferation and cell growth in breast cancer cells by targeting p21(Cip).

    PubMed

    Chaudhary, S; Madhukrishna, B; Adhya, A K; Keshari, S; Mishra, S K

    2016-04-18

    Caspase 7 (CASP7) expression has important function during cell cycle progression and cell growth in certain cancer cells and is also involved in the development and differentiation of dental tissues. However, the function of CASP7 in breast cancer cells is unclear. The aim of this study was to analyze the expression of CASP7 in breast carcinoma patients and determine the role of CASP7 in regulating tumorigenicity in breast cancer cells. In this study, we show that the CASP7 expression is high in breast carcinoma tissues compared with normal counterpart. The ectopic expression of CASP7 is significantly associated with ERα expression status and persistently elevated in different stages of the breast tumor grades. High level of CASP7 expression showed better prognosis in breast cancer patients with systemic endocrine therapy as observed from Kaplan-Meier analysis. S3 and S4, estrogen responsive element (ERE) in the CASP7 promoter, is important for estrogen-ERα-mediated CASP7 overexpression. Increased recruitment of p300, acetylated H3 and pol II in the ERE region of CASP7 promoter is observed after hormone stimulation. Ectopic expression of CASP7 in breast cancer cells results in cell growth and proliferation inhibition via p21(Cip) reduction, whereas small interfering RNA (siRNA) mediated reduction of CASP7 rescued p21(Cip) levels. We also show that pro- and active forms of CASP7 is located in the nucleus apart from cytoplasmic region of breast cancer cells. The proliferation and growth of breast cancer cells is significantly reduced by broad-spectrum peptide inhibitors and siRNA of CASP7. Taken together, our findings show that CASP7 is aberrantly expressed in breast cancer and contributes to cell growth and proliferation by downregulating p21(Cip) protein, suggesting that targeting CASP7-positive breast cancer could be one of the potential therapeutic strategies.

  4. The GAS5/miR-222 Axis Regulates Proliferation of Gastric Cancer Cells Through the PTEN/Akt/mTOR Pathway.

    PubMed

    Li, Yanhua; Gu, Junjiao; Lu, Hong

    2017-12-01

    Several lines of evidence have indicated that growth arrest-specific transcript 5 (GAS5) functions as a tumor suppressor and is aberrantly expressed in multiple cancers. GAS5 was found to be downregulated in gastric cancer (GC) tissues, and ectopic expression of GAS5 inhibited GC cell proliferation. The present study aimed to explore the underlying mechanisms of GAS5 involved in GC cell proliferation. GAS5 and miR-222 expressions in GC cell lines were estimated by quantitative real-time polymerase chain reaction. The effects of GAS5 and miR-222 on GC cell proliferation were assessed by MTT assay and 5-bromo-2-deoxyuridine (BrdU) incorporation assays. The interaction between GAS5 and miR-222 was confirmed by luciferase reporter assay and RNA immunoprecipitation assay. The protein levels of the phosphatase and tensin homolog (PTEN), phosphorylated protein kinase B (Akt) (p-Akt), Akt, phosphorylated mammalian target of rapamycin (mTOR) (p-mTOR), and mTOR were determined by western blot. GAS5 was downregulated and miR-222 was upregulated in GC cells. GAS5 directly targeted and suppressed miR-222 expression. GAS5 overexpression and miR-222 inhibition suppressed cell proliferation, increased PTEN protein level and decreased p-Akt and p-mTOR protein levels in GC cells while GAS5 knockdown and miR-222 overexpression exhibited the opposite effects. Moreover, mechanistic analyses revealed that GAS5 regulated GC cell proliferation through the PTEN/Akt/mTOR pathway by negatively regulating miR-222. GAS5/miR-222 axis regulated proliferation of GC cells through the PTEN/Akt/mTOR pathway, which facilitated the development of lncRNA-directed therapy against this deadly disease.

  5. Cell proliferation by silk gut incorporating FGF-2 protein microcrystals.

    PubMed

    Kotani, Eiji; Yamamoto, Naoto; Kobayashi, Isao; Uchino, Keiro; Muto, Sayaka; Ijiri, Hiroshi; Shimabukuro, Junji; Tamura, Toshiki; Sezutsu, Hideki; Mori, Hajime

    2015-06-08

    Silk gut processed from the silk glands of the silkworm could be an ideal biodegradable carrier for cell growth factors. We previously demonstrated that polyhedra, microcrystals of Cypovirus 1 polyhedrin, can serve as versatile carrier proteins. Here, we report the generation of a transgenic silkworm that expresses polyhedrin together with human basic fibroblast growth factor (FGF-2) in its posterior silk glands to utilize silk gut as a proteinaceous carrier to protect and slowly release active cell growth factors. In the posterior silk glands, polyhedrin formed polyhedral microcrystals, and FGF-2 became encapsulated within the polyhedra due to a polyhedron-immobilization signal. Silk gut powder prepared from posterior silk glands containing polyhedron-encapsulated FGF-2 stimulated the phosphorylation of p44/p42 MAP kinase and induced the proliferation of serum-starved NIH3T3 cells by releasing bioactive FGF-2. Even after a one-week incubation at 25 °C, significantly higher biological activity of FGF-2 was observed for silk gut powder incorporating polyhedron-encapsulated FGF-2 relative to silk gut powder with non-encapsulated FGF-2. Our results demonstrate that posterior silk glands incorporating polyhedron-encapsulated FGF-2 are applicable to the preparation of biodegradable silk gut, which can protect and release FGF-2 that is produced in a virus- and serum-free expression system with significant application potential.

  6. 6-mercaptopurine promotes energetic failure in proliferating T cells

    PubMed Central

    Fernández-Ramos, Ana A.; Marchetti-Laurent, Catherine; Poindessous, Virginie; Antonio, Samantha; Laurent-Puig, Pierre; Bortoli, Sylvie; Loriot, Marie-Anne; Pallet, Nicolas

    2017-01-01

    The anticancer drug 6-mercaptopurine (6-MP) inhibits de novo purine synthesis and acts as an antiproliferative agent by interfering with protein, DNA and RNA synthesis and promoting apoptosis. Metabolic reprogramming is crucial for tumor progression to foster cancer cells growth and proliferation, and is regulated by mechanistic target of rapamycin (mTOR) and AMP-activated protein kinase (AMPK) as well as the oncogenes Myc and hypoxia inducible factor 1α (HIF-1α). We hypothesized that 6-MP impacts metabolic remodeling through its action on nucleotide synthesis. The aim of our study is to provide a comprehensive characterization of the metabolic changes induced by 6-MP in leukemic T cells. Our results indicate that exposition to 6-MP rapidly reduces intracellular ATP concentration, leading to the activation of AMPK. In turn, mTOR, an AMPK target, was inhibited, and the expression of HIF-1α and Myc was reduced upon 6-MP incubation. As a consequence of these inhibitions, glucose and glutamine fluxes were strongly decreased. Notably, no difference was observed on glucose uptake upon exposition to 6-MP. In conclusion, our findings provide new insights into how 6-MP profoundly impacts cellular energetic metabolism by reducing ATP production and decreasing glycolytic and glutaminolytic fluxes, and how 6-MP modifies human leukemic T cells metabolism with potential antiproliferative effects. PMID:28574837

  7. 6-mercaptopurine promotes energetic failure in proliferating T cells.

    PubMed

    Fernández-Ramos, Ana A; Marchetti-Laurent, Catherine; Poindessous, Virginie; Antonio, Samantha; Laurent-Puig, Pierre; Bortoli, Sylvie; Loriot, Marie-Anne; Pallet, Nicolas

    2017-06-27

    The anticancer drug 6-mercaptopurine (6-MP) inhibits de novo purine synthesis and acts as an antiproliferative agent by interfering with protein, DNA and RNA synthesis and promoting apoptosis. Metabolic reprogramming is crucial for tumor progression to foster cancer cells growth and proliferation, and is regulated by mechanistic target of rapamycin (mTOR) and AMP-activated protein kinase (AMPK) as well as the oncogenes Myc and hypoxia inducible factor 1α (HIF-1α). We hypothesized that 6-MP impacts metabolic remodeling through its action on nucleotide synthesis. The aim of our study is to provide a comprehensive characterization of the metabolic changes induced by 6-MP in leukemic T cells. Our results indicate that exposition to 6-MP rapidly reduces intracellular ATP concentration, leading to the activation of AMPK. In turn, mTOR, an AMPK target, was inhibited, and the expression of HIF-1α and Myc was reduced upon 6-MP incubation. As a consequence of these inhibitions, glucose and glutamine fluxes were strongly decreased. Notably, no difference was observed on glucose uptake upon exposition to 6-MP. In conclusion, our findings provide new insights into how 6-MP profoundly impacts cellular energetic metabolism by reducing ATP production and decreasing glycolytic and glutaminolytic fluxes, and how 6-MP modifies human leukemic T cells metabolism with potential antiproliferative effects.

  8. 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.

  9. Cell proliferation and hair cell addition in the ear of the goldfish, Carassius auratus

    NASA Technical Reports Server (NTRS)

    Lanford, P. J.; Presson, J. C.; Popper, A. N.

    1996-01-01

    Cell proliferation and hair cell addition have not been studied in the ears of otophysan fish, a group of species who have specialized hearing capabilities. In this study we used the mitotic S-phase marker bromodeoxyuridine (BrdU) to identify proliferating cells in the ear of one otophysan species, Carassius auratus (the goldfish). Animals were sacrificed at 3 h or 5 days postinjection with BrdU and processed for immunocytochemistry. The results of the study show that cell proliferation occurs in all of the otic endorgans and results in the addition of new hair cells. BrdU-labeled cells were distributed throughout all epithelia, including the primary auditory endorgan (saccule), where hair cell phenotypes vary considerably along the rostrocaudal axis. This study lays the groundwork for our transmission electron microscopy study of proliferative cells in the goldfish ear (Presson et al., Hearing Research 100 (1996) 10-20) as well as future studies of hair cell development in this species. The ability to predict, based on epithelial location, the future phenotype of developing hair cells in the saccule of the goldfish make that endorgan a particularly powerful model system for the investigation of early hair cell differentiation.

  10. Aberrant expression of long noncoding RNAs in cumulus cells isolated from PCOS patients.

    PubMed

    Huang, Xin; Hao, Cuifang; Bao, Hongchu; Wang, Meimei; Dai, Huangguan

    2016-01-01

    To describe the long noncoding RNA (lncRNA) profiles in cumulus cells isolated from polycystic ovary syndrome (PCOS) patients by employing a microarray and in-depth bioinformatics analysis. This information will help us understand the occurrence and development of PCOS. In this study, we used a microarray to describe lncRNA profiles in cumulus cells isolated from ten patients (five PCOS and five normal women). Several differentially expressed lncRNAs were chosen to validate the microarray results by quantitative RT-PCR (qRT-PCR). Then, the differentially expressed lncRNAs were classified into three subgroups (HOX loci lncRNA, enhancer-like lncRNA, and lincRNA) to deduce their potential features. Furthermore, a lncRNA/mRNA co-expression network was constructed by using the Cytoscape software (V2.8.3, http://www.cytoscape.org/ ). We observed that 623 lncRNAs and 260 messenger RNAs (mRNAs) were significantly up- or down-regulated (≥2-fold change), and these differences could be used to discriminate cumulus cells of PCOS from those of normal patients. Five differentially expressed lncRNAs (XLOC_011402, ENST00000454271, ENST00000433673, ENST00000450294, and ENST00000432431) were selected to validate the microarray results using quantitative RT-PCR (qRT-PCR). The qRT-PCR results were consistent with the microarray data. Further analysis indicated that many differentially expressed lncRNAs were transcribed from chromosome 2 and may act as enhancers to regulate their neighboring protein-coding genes. Forty-three lncRNAs and 29 mRNAs were used to construct the coding-non-coding gene co-expression network. Most pairs positively correlated, and one mRNA correlated with one or more lncRNAs. Our study is the first to determine genome-wide lncRNA expression patterns in cumulus cells isolated from PCOS patients by microarray. The results show that clusters of lncRNAs were aberrantly expressed in cumulus cells of PCOS patients compared with those of normal women, which revealed

  11. Tight junction-based epithelial microenvironment and cell proliferation.

    PubMed

    Tsukita, S; Yamazaki, Y; Katsuno, T; Tamura, A; Tsukita, S

    2008-11-24

    Belt-like tight junctions (TJs), referred to as zonula occludens, have long been regarded as a specialized differentiation of epithelial cell membranes. They are required for cell adhesion and paracellular barrier functions, and are now thought to be partly involved in fence functions and in cell polarization. Recently, the molecular bases of TJs have gradually been unveiled. TJs are constructed by TJ strands, whose basic frameworks are composed of integral membrane proteins with four transmembrane domains, designated claudins. The claudin family is supposedly composed of at least 24 members in mice and humans. Other types of integral membrane proteins with four transmembrane domains, namely occludin and tricellulin, as well as the single transmembrane proteins, JAMs (junctional adhesion molecules) and CAR (coxsackie and adenovirus receptor), are associated with TJ strands, and the high-level organization of TJ strands is likely to be established by membrane-anchored scaffolding proteins, such as ZO-1/2. Recent functional analyses of claudins in cell cultures and in mice have suggested that claudin-based TJs may have pivotal functions in the regulation of the epithelial microenvironment, which is critical for various biological functions such as control of cell proliferation. These represent the dawn of 'Barriology' (defined by Shoichiro Tsukita as the science of barriers in multicellular organisms). Taken together with recent reports regarding changes in claudin expression levels, understanding the regulation of the TJ-based microenvironment system will provide new insights into the regulation of polarization in the respect of epithelial microenvironment system and new viewpoints for developing anticancer strategies.

  12. Effect of irradiation on human T-cell proliferation: low dose irradiation stimulates mitogen-induced proliferation and function of the suppressor/cytotoxic T-cell subset.

    PubMed

    Gualde, N; Goodwin, J S

    1984-04-01

    Unfractionated human T cells exposed to 10-50 rad of X irradiation incorporated less [3H]thymidine than nonirradiated T cells when subsequently cultured with PHA or Con A. The cytotoxic/suppressor T-cell subset, isolated as either OKT8(+) or OKT4(-) cells, demonstrated significantly enhanced [3H]thymidine incorporation in PHA- or Con A-stimulated cultures after exposure to 10-50 rad, compared to unirradiated cells, while the proliferation of the OKT4(+) helper/inducer subset was inhibited by low dose irradiation. It has been previously reported that approximately 30% of the cytotoxic/suppressor subset also stains with OKM1. When the cytotoxic/suppressor subset was further subdivided into OKT4(-), OKM1(+), and OKT4(-), OKM1(-) cells, proliferation of the OKT4(-), OKM1(+) population was inhibited by exposure to 25 rad while proliferation of the OKT4(-), OKM1(-) population was stimulated. The increase in proliferation of the cytotoxic/suppressor T-cell subset after low dose irradiation is paralleled by an increase in suppressor activity of these cells. T cells exposed to 25 rad and then cultured with Con A for 48 hr caused greater inhibition of IgG production when added to fresh autologous lymphocytes stimulated by pokeweed mitogen than did unirradiated cells. Thus, low dose irradiation enhances both the proliferation and function of the human suppressor T-cell subset.

  13. Effect of irradiation on human T-cell proliferation: low dose irradiation stimulates mitogen-induced proliferation and function of the suppressor/cytotoxic T-cell subset

    SciTech Connect

    Gualde, N.; Goodwin, J.S.

    1984-04-01

    Unfractionated human T cells exposed to 10-50 rad of X irradiation incorporated less (/sup 3/H)thymidine than nonirradiated T cells when subsequently cultured with PHA or Con A. The cytotoxic/suppressor T-cell subset, isolated as either OKT8(+) or OKT4(-) cells, demonstrated significantly enhanced (/sup 3/H)thymidine incorporation in PHA- or Con A-stimulated cultures after exposure to 10-50 rad, compared to unirradiated cells, while the proliferation of the OKT4(+) helper/inducer subset was inhibited by low dose irradiation. It has been previously reported that approximately 30% of the cytotoxic/suppressor subset also stains with OKM1. When the cytotoxic/suppressor subset was further subdivided into OKT4(-), OKM1(+), andmore » OKT4(-), OKM1(-) cells, proliferation of the OKT4(-), OKM1(+) population was inhibited by exposure to 25 rad while proliferation of the OKT4(-), OKM1(-) population was stimulated. The increase in proliferation of the cytotoxic/suppressor T-cell subset after low dose irradiation is paralleled by an increase in suppressor activity of these cells. T cells exposed to 25 rad and then cultured with Con A for 48 hr caused greater inhibition of IgG production when added to fresh autologous lymphocytes stimulated by pokeweed mitogen than did unirradiated cells. Thus, low dose irradiation enhances both the proliferation and function of the human suppressor T-cell subset.« less

  14. CD4+ Foxp3+ T cells promote aberrant immunoglobulin G production and maintain CD8+ T-cell suppression during chronic liver disease.

    PubMed

    Tedesco, Dana; Thapa, Manoj; Gumber, Sanjeev; Elrod, Elizabeth J; Rahman, Khalidur; Ibegbu, Chris C; Magliocca, Joseph F; Adams, Andrew B; Anania, Frank; Grakoui, Arash

    2017-02-01

    Persistent hepatotropic viral infections are a common etiologic agent of chronic liver disease. Unresolved infection can be attributed to nonfunctional intrahepatic CD8+ T-cell responses. In light of dampened CD8 + T-cell responses, liver disease often manifests systemically as immunoglobulin (Ig)-related syndromes due to aberrant B-cell functions. These two opposing yet coexisting phenomena implicate the potential of altered CD4 + T-cell help. Elevated CD4 + forkhead box P3-positive (Foxp3+) T cells were evident in both human liver disease and a mouse model of chemically induced liver injury despite marked activation and spontaneous IgG production by intrahepatic B cells. While this population suppressed CD8 + T-cell responses, aberrant B-cell activities were maintained due to expression of CD40 ligand on a subset of CD4 + Foxp3+ T cells. In vivo blockade of CD40 ligand attenuated B-cell abnormalities in a mouse model of liver injury. A phenotypically similar population of CD4 + Foxp3+, CD40 ligand-positive T cells was found in diseased livers explanted from patients with chronic hepatitis C infection. This population was absent in nondiseased liver tissues and peripheral blood. Liver disease elicits alterations in the intrahepatic CD4 + T-cell compartment that suppress T-cell immunity while concomitantly promoting aberrant IgG mediated manifestations. (Hepatology 2017;65:661-677). © 2016 by the American Association for the Study of Liver Diseases.

  15. Inter- and Intra-Chromosomal Aberrations in Human Cells Exposed in vitro to Space-like Radiations

    NASA Technical Reports Server (NTRS)

    Hada, Megumi; Cucinotta, F. A.; Gonda, S. R.; Wu, H.

    2005-01-01

    Energetic heavy ions pose a great health risk to astronauts in extended ISS and future exploration missions. High-LET heavy ions are particularly effective in causing various biological effects, including cell inactivation, genetic mutations and cancer induction. Most of these biological endpoints are closely related to chromosomal damage, which can be utilized as a biomarker for radiation insults. Previously, we had studied chromosome aberrations in human lymphocytes and fibroblasts induced by both low- and high-LET radiation using FISH and multicolor fluorescence in situ hybridization (mFISH) techniques. In this study, we exposed human cells in vitro to gamma rays and energetic particles of varying types and energies and dose rates, and analyzed chromosomal damages using the multicolor banding in situ hybridization (mBAND) procedure. Confluent human epithelial cells and lymphocytes were exposed to energetic heavy ions at NASA Space Radiation Laboratory (NSRL) at the Brookhaven National Laboratory (Upton, NY) or Cs-137 gamma radiation source at the Baylor College (Houston, TX). After colcemid and Calyculin A treatment, cells were fixed and painted with XCyte3 mBAND kit (MetaSystems) and chromosome aberrations were analyzed with mBAND analysis system (MetaSystems). With this technique, individually painted chromosomal bands on one chromosome allowed the identification of interchromosomal aberrations (translocation to unpainted chromosomes) and intrachromosomal aberrations (inversions and deletions within a single painted chromosome). The possible relationship between the frequency of inter- and intra-chromosomal exchanges and the track structure of radiation is discussed. The work was supported by the NASA Space Radiation Health Program.

  16. SASH1 regulates proliferation, apoptosis, and invasion of osteosarcoma cell.

    PubMed

    Meng, Qingbing; Zheng, Minqian; Liu, Hongbing; Song, Changzhi; Zhang, Wensheng; Yan, Juan; Qin, Ling; Liu, Xiaolan

    2013-01-01

    SASH1, a member of the SLY-family of signal adapter proteins, is a candidate tumor suppressor in breast and colon cancer. The SASH1 protein possesses both the SH3 and SAM domains, indicating that it may play an important role in intracellular signal transduction. Reduced expression of SASH1 is closely related to tumor growth, invasion, metastasis, and poor prognosis. However, the biological role of SASH1 remains unknown in osteosarcoma. To unravel the function of SASH1, we explored the expression of SASH1 in osteosarcoma tissues and its correlation to the clinical pathology of osteosarcoma and analyzed the relationship between SASH1 expression and cell cycle, apoptosis and invasion of osteosarcoma MG-63 cells, using the flow cytometry analysis and transwell invasion chamber experiments. Furthermore, the effect of SASH1 on the expression of cyclin D1, caspase-3, matrix metalloproteinase (MMP)-9 were observed by western blot. Our results showed that the expression rate of SASH1 mRNA in osteosarcoma tissues was significantly lower than that in normal bone tissue (p = 0.000), that the expression rate of SASH1 mRNA in the carcinoma tissues from patients with lung metastasis was significantly lower than that from patients without lung metastasis (p = 0.041), and that the expression rate of SASH1 mRNA also decreased with increasing Enneking stage (p = 0.032). However, the mRNA expression of SASH1 in osteosarcoma was independent of the patient's gender, age, and tumor size (p = 0.983, 0.343, 0.517, respectively). The SASH1 protein displayed a down-regulation in osteosarcoma tissues compared to normal bone tissue (p = 0.000), displayed a down-regulation in osteosarcoma tissues from patients with lung metastasis compared to from patients without lung metastasis (p = 0.000), and displayed a gradual decrease with increasing Enneking stage (p = 0.000). In addition, the MG-63 cells from pcDNA3.1-SASH1 group exhibited significantly reduced cell viability, proliferation, and

  17. The XTT Cell Proliferation Assay Applied to Cell Layers Embedded in Three-Dimensional Matrix

    PubMed Central

    Huyck, Lynn; Ampe, Christophe

    2012-01-01

    Abstract Cell proliferation, a main target in cancer therapy, is influenced by the surrounding three-dimensional (3D) extracellular matrix (ECM). In vitro drug screening is, thus, optimally performed under conditions in which cells are grown (embedded or trapped) in dense 3D matrices, as these most closely mimic the adhesive and mechanical properties of natural ECM. Measuring cell proliferation under these conditions is, however, technically more challenging compared with two-dimensional (2D) culture and other “3D culture conditions,” such as growth on top of a matrix (pseudo-3D) or in spongy scaffolds with large pore sizes. Consequently, such measurements are only slowly applied on a wider scale. To advance this, we report on the equal quality (dynamic range, background, linearity) of measuring the proliferation of cell layers embedded in dense 3D matrices (collagen, Matrigel) compared with cells in 2D culture using the easy (one-step) and in 2D well-validated, 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT)-assay. The comparison stresses the differences in proliferation kinetics and drug sensitivity of matrix-embedded cells versus 2D culture. Using the specific cell-layer-embedded 3D matrix setup, quantitative measurements of cell proliferation and cell invasion are shown to be possible in similar assay conditions, and cytostatic, cytotoxic, and anti-invasive drug effects can thus be reliably determined and compared in physiologically relevant settings. This approach in the 3D matrix holds promise for improving early-stage, high-throughput drug screening, targeting either highly invasive or highly proliferative subpopulations of cancers or both. PMID:22574651

  18. 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

  19. Transient inhibition of cell proliferation does not compromise self-renewal of mouse embryonic stem cells

    SciTech Connect

    Wang, Ruoxing; Guo, Yan-Lin, E-mail: yanlin.guo@usm.edu

    2012-10-01

    Embryonic stem cells (ESCs) have unlimited capacity for self-renewal and can differentiate into various cell types when induced. They also have an unusual cell cycle control mechanism driven by constitutively active cyclin dependent kinases (Cdks). In mouse ESCs (mESCs). It is proposed that the rapid cell proliferation could be a necessary part of mechanisms that maintain mESC self-renewal and pluripotency, but this hypothesis is not in line with the finding in human ESCs (hESCs) that the length of the cell cycle is similar to differentiated cells. Therefore, whether rapid cell proliferation is essential for the maintenance of mESC state remainsmore » unclear. We provide insight into this uncertainty through chemical intervention of mESC cell cycle. We report here that inhibition of Cdks with olomoucine II can dramatically slow down cell proliferation of mESCs with concurrent down-regulation of cyclin A, B and E, and the activation of the Rb pathway. However, mESCs display can recover upon the removal of olomoucine II and are able to resume normal cell proliferation without losing self-renewal and pluripotency, as demonstrated by the expression of ESC markers, colony formation, embryoid body formation, and induced differentiation. We provide a mechanistic explanation for these observations by demonstrating that Oct4 and Nanog, two major transcription factors that play critical roles in the maintenance of ESC properties, are up-regulated via de novo protein synthesis when the cells are exposed to olomoucine II. Together, our data suggest that short-term inhibition of cell proliferation does not compromise the basic properties of mESCs. -- Highlights: Black-Right-Pointing-Pointer Inhibition of Cdks slows down mESCs proliferation. Black-Right-Pointing-Pointer mESCs display remarkable recovery capacity from short-term cell cycle interruption. Black-Right-Pointing-Pointer Short-term cell cycle interruption does not compromise mESC self-renewal. Black

  20. Aberrant immunoglobulin class switch recombination and switch translocations in activated B cell-like diffuse large B cell lymphoma.

    PubMed

    Lenz, Georg; Nagel, Inga; Siebert, Reiner; Roschke, Anna V; Sanger, Warren; Wright, George W; Dave, Sandeep S; Tan, Bruce; Zhao, Hong; Rosenwald, Andreas; Muller-Hermelink, Hans Konrad; Gascoyne, Randy D; Campo, Elias; Jaffe, Elaine S; Smeland, Erlend B; Fisher, Richard I; Kuehl, W Michael; Chan, Wing C; Staudt, Louis M

    2007-03-19

    To elucidate the mechanisms underlying chromosomal translocations in diffuse large B cell lymphoma (DLBCL), we investigated the nature and extent of immunoglobulin class switch recombination (CSR) in these tumors. We used Southern blotting to detect legitimate and illegitimate CSR events in tumor samples of the activated B cell-like (ABC), germinal center B cell-like (GCB), and primary mediastinal B cell lymphoma (PMBL) subgroups of DLBCL. The frequency of legitimate CSR was lower in ABC DLBCL than in GCB DLBCL and PMBL. In contrast, ABC DLBCL had a higher frequency of internal deletions within the switch mu (Smu) region compared with GCB DLBCL and PMBL. ABC DLBCLs also had frequent deletions within Sgamma and other illegitimate switch recombinations. Sequence analysis revealed ongoing Smu deletions within ABC DLBCL tumor clones, which were accompanied by ongoing duplications and activation-induced cytidine deaminase-dependent somatic mutations. Unexpectedly, short fragments derived from multiple chromosomes were interspersed within Smu in one case. These findings suggest that ABC DLBCLs have abnormalities in the regulation of CSR that could predispose to chromosomal translocations. Accordingly, aberrant switch recombination was responsible for translocations in ABC DLBCLs involving BCL6, MYC, and a novel translocation partner, SPIB.

  1. Gallic acid reduces cell viability, proliferation, invasion and angiogenesis in human cervical cancer cells

    PubMed Central

    ZHAO, BING; HU, MENGCAI

    2013-01-01

    Gallic acid is a trihydroxybenzoic acid, also known as 3,4,5-trihydroxybenzoic acid, which is present in plants worldwide, including Chinese medicinal herbs. Gallic acid has been shown to have cytotoxic effects in certain cancer cells, without damaging normal cells. The objective of the present study was to determine whether gallic acid is able to inhibit human cervical cancer cell viability, proliferation and invasion and suppress cervical cancer cell-mediated angiogenesis. Treatment of HeLa and HTB-35 human cancer cells with gallic acid decreased cell viability in a dose-dependent manner. BrdU proliferation and tube formation assays indicated that gallic acid significantly decreased human cervical cancer cell proliferation and tube formation in human umbilical vein endothelial cells, respectively. Additionally, gallic acid decreased HeLa and HTB-35 cell invasion in vitro. Western blot analysis demonstrated that the expression of ADAM17, EGFR, p-Akt and p-Erk was suppressed by gallic acid in the HeLa and HTB-35 cell lines. These data indicate that the suppression of ADAM17 and the downregulation of the EGFR, Akt/p-Akt and Erk/p-Erk signaling pathways may contribute to the suppression of cancer progression by Gallic acid. Gallic acid may be a valuable candidate for the treatment of cervical cancer. PMID:24843386

  2. Chromosome Aberrations in Human Epithelial Cells Exposed Los Alamos High-Energy Secondary Neutrons: M-BAND Analysis

    NASA Technical Reports Server (NTRS)

    Hada, M.; Saganti, P. B.; Gersey, B.; Wilkins, R.; Cucinotta, F. A.; Wu, H.

    2007-01-01

    High-energy secondary neutrons, produced by the interaction of galactic cosmic rays (GCR) with the atmosphere, spacecraft structure and planetary surfaces, contribute a significant fraction to the dose equivalent radiation measurement in crew members and passengers of commercial aviation travel as well as astronauts in space missions. The Los Alamos Nuclear Science Center (LANSCE) neutron facility's 30L beam line (4FP30L-A/ICE House) is known to generate neutrons that simulate the secondary neutron spectrum of the Earth's atmosphere at high altitude. The neutron spectrum is also similar to that measured onboard spacecrafts like the MIR and the International Space Station (ISS). To evaluate the biological damage, we exposed human epithelial cells in vitro to the LANSCE neutron beams with an entrance dose rate of 2.5 cGy/hr, and studied the induction of chromosome aberrations that were identified with multicolor-banding in situ hybridization (mBAND) technique. With this technique, individually painted chromosomal bands on one chromosome allowed the identification of inter-chromosomal aberrations (translocation to unpainted chromosomes) and intra-chromosomal aberrations (inversions and deletions within a single painted chromosome). Compared to our previous results with gamma-rays and 600 MeV/nucleon Fe ions of high dose rate at NSRL (NASA Space Radiation Laboratory at Brookhaven National Laboratory), the neutron data from the LANSCE experiments showed significantly higher frequency of chromosome aberrations. However, detailed analysis of the inversion type revealed that all of the three radiation types in the study induced a low incidence of simple inversions. Most of the inversions in gamma-ray irradiated samples were accompanied by other types of intrachromosomal aberrations but few inversions were accompanied by interchromosomal aberrations. In contrast, neutrons and Fe ions induced a significant fraction of inversions that involved complex rearrangements of both

  3. 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

  4. 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.

  5. 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

  6. Melatonin protects bone marrow mesenchymal stem cells against iron overload-induced aberrant differentiation and senescence.

    PubMed

    Yang, Fan; Yang, Lei; Li, Yuan; Yan, Gege; Feng, Chao; Liu, Tianyi; Gong, Rui; Yuan, Ye; Wang, Ning; Idiiatullina, Elina; Bikkuzin, Timur; Pavlov, Valentin; Li, Yang; Dong, Chaorun; Wang, Dawei; Cao, Yang; Han, Zhenbo; Zhang, Lai; Huang, Qi; Ding, Fengzhi; Bi, Zhengang; Cai, Benzhi

    2017-10-01

    Bone marrow mesenchymal stem cells (BMSCs) are an expandable population of stem cells which can differentiate into osteoblasts, chondrocytes and adipocytes. Dysfunction of BMSCs in response to pathological stimuli contributes to bone diseases. Melatonin, a hormone secreted from pineal gland, has been proved to be an important mediator in bone formation and mineralization. The aim of this study was to investigate whether melatonin protected against iron overload-induced dysfunction of BMSCs and its underlying mechanisms. Here, we found that iron overload induced by ferric ammonium citrate (FAC) caused irregularly morphological changes and markedly reduced the viability in BMSCs. Consistently, osteogenic differentiation of BMSCs was significantly inhibited by iron overload, but melatonin treatment rescued osteogenic differentiation of BMSCs. Furthermore, exposure to FAC led to the senescence in BMSCs, which was attenuated by melatonin as well. Meanwhile, melatonin was able to counter the reduction in cell proliferation by iron overload in BMSCs. In addition, protective effects of melatonin on iron overload-induced dysfunction of BMSCs were abolished by its inhibitor luzindole. Also, melatonin protected BMSCs against iron overload-induced ROS accumulation and membrane potential depolarization. Further study uncovered that melatonin inhibited the upregulation of p53, ERK and p38 protein expressions in BMSCs with iron overload. Collectively, melatonin plays a protective role in iron overload-induced osteogenic differentiation dysfunction and senescence through blocking ROS accumulation and p53/ERK/p38 activation. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. NoxO1 Controls Proliferation of Colon Epithelial Cells.

    PubMed

    Moll, Franziska; Walter, Maria; Rezende, Flávia; Helfinger, Valeska; Vasconez, Estefania; De Oliveira, Tiago; Greten, Florian R; Olesch, Catherine; Weigert, Andreas; Radeke, Heinfried H; Schröder, Katrin

    2018-01-01

    Reactive oxygen species (ROS) produced by enzymes of the NADPH oxidase family serve as second messengers for cellular signaling. Processes such as differentiation and proliferation are regulated by NADPH oxidases. In the intestine, due to the exceedingly fast and constant renewal of the epithelium both processes have to be highly controlled and balanced. Nox1 is the major NADPH oxidase expressed in the gut, and its function is regulated by cytosolic subunits such as NoxO1. We hypothesize that the NoxO1-controlled activity of Nox1 contributes to a proper epithelial homeostasis and renewal in the gut. NoxO1 is highly expressed in the colon. Knockout of NoxO1 reduces the production of superoxide in colon crypts and is not subsidized by an elevated expression of its homolog p47phox. Knockout of NoxO1 increases the proliferative capacity and prevents apoptosis of colon epithelial cells. In mouse models of dextran sulfate sodium (DSS)-induced colitis and azoxymethane/DSS induced colon cancer, NoxO1 has a protective role and may influence the population of natural killer cells. NoxO1 affects colon epithelium homeostasis and prevents inflammation.

  8. Shikonin Suppresses Skin Carcinogenesis via Inhibiting Cell Proliferation

    PubMed Central

    Ren, Amy; Li, Teena; Jin, Rong; Li, Guohong; Gu, Xin; Shi, Runhua; Zhao, Yunfeng

    2015-01-01

    The M2 isoform of pyruvate kinase M2 (PKM2) has been shown to be up-regulated in human skin cancers. To test whether PKM2 may be a target for chemoprevention, shikonin, a natural product from the root of Lithospermum erythrorhizon and a specific inhibitor of PKM2, was used in a chemically-induced mouse skin carcinogenesis study. The results revealed that shikonin treatment suppressed skin tumor formation. Morphological examinations and immunohistochemical staining of the skin epidermal tissues suggested that shikonin inhibited cell proliferation without inducing apoptosis. Although shikonin alone suppressed PKM2 activity, it did not suppress tumor promoter-induced PKM2 activation in the skin epidermal tissues at the end of the skin carcinogenesis study. To reveal the potential chemopreventive mechanism of shikonin, an antibody microarray analysis was performed, and the results showed that the transcription factor ATF2 and its downstream target Cdk4 were up-regulated by chemical carcinogen treatment; whereas these up-regulations were suppressed by shikonin. In a promotable skin cell model, the nuclear levels of ATF2 were increased during tumor promotion, whereas this increase was inhibited by shikonin. Furthermore, knockdown of ATF2 decreased the expression levels of Cdk4 and Fra-1 (a key subunit of the activator protein 1. In summary, these results suggest that shikonin, rather than inhibiting PKM2 in vivo, suppresses the ATF2 pathway in skin carcinogenesis. PMID:25961580

  9. Dose-related cell proliferation in medaka (Oryzias latipes) after N-nitrosodiethylamine exposure

    SciTech Connect

    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

  10. Dissecting GRB7-mediated signals for proliferation and migration in HER2 overexpressing breast tumor cells: GTP-ase rules.

    PubMed

    Pradip, De; Bouzyk, Mark; Dey, Nandini; Leyland-Jones, Brian

    2013-01-01

    Amplification of human Her2 and its aberrant signaling in 20-30% of early breast cancer patients is responsible for highly aggressive tumors with poor outcome. Grb7 is reported to be co-amplified with Her2. We report a concurrent high expression of mRNA (from FFPE tumor samples; mRNA correlation, Pearson r(2)= 0.806), and high levels of GRB7 protein (immunoblot) in HER2+ breast cancer cell lines. We demonstrated the signaling mechanism of HER2 and downstream effectors that contributes to proliferation and migration. Using HER2+ and trastuzumab-resistant breast cancer cell lines, we identified the interaction between GRB7 and HER2 in the control of HER2+ cell proliferation. Our co-IP data show that GRB7 recruits SHC into the HER2-GRB7 signaling complex. This complex formation leads to activation of RAS-GTP. We also observed that following integrin engagement, GRB7 is phosphorylated at tyrosine in a p-FAK (Y397) dependent manner. This FAK-GRB7 complex leads to downstream activation of RAC1-GTP (responsible for migration) probably through the recruitment of VAV2. Our CO-IP data demonstrate that GRB7 directly binds with VAV2 following fibronectin engagement in HER2+ cells. To address whether GRB7 could serve as a pathway specific therapeutic target, we used siRNA to suppress GRB7 expression. Knockdown of GRB7 expression in the HER2+ breast cancer cell lines decreases RAS activation, cell proliferation, 2D and 3D colony formation and also blocked integrin-mediated RAC1 activation along with integrin-directed cell migration. These findings dissected the HER2-mediated signaling cascade into (1) HER2+ cell proliferation (HER2-GRB7-SHC-RAS) and (2) HER2+ cell migration (alpha5 beta1/alpha4 beta1-FAK-GRB7-VAV2-RAC1). Our data clearly demonstrate that a coupling of GRB7 with HER2 is required for the proliferative and migratory signals in HER2+ breast tumor cells.

  11. 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.

  12. Knockdown of Long Noncoding RNA FTX Inhibits Proliferation, Migration, and Invasion in Renal Cell Carcinoma Cells.

    PubMed

    He, Xiangfei; Sun, Fuguang; Guo, Fengfu; Wang, Kai; Gao, Yisheng; Feng, Yanfei; Song, Bin; Li, Wenzhi; Li, Yang

    2017-01-26

    Renal cell carcinoma (RCC) is one of the most common kidney cancers worldwide. Although great progressions have been made in the past decades, its morbidity and lethality remain increasing. Long noncoding RNAs (lncRNAs) are demonstrated to play significant roles in the tumorigenesis. This study aimed to investigate the detailed roles of lncRNA FTX in RCC cell proliferation and metastasis. Our results showed that the transcript levels of FTX in both clinical RCC tissues and the cultured RCC cells were significantly upregulated and associated with multiple clinical parameters of RCC patients, including familial status, tumor sizes, lymphatic metastasis, and TNM stages. With cell proliferation assays, colony formation assays, and cell cycle assays, we testified that knockdown of FTX in A498 and ACHIN cells with specific shRNAs inhibited cell proliferation rate, colony formation ability, and arrested cell cycle in the G0/G1 phase. FTX depletion also suppressed cell migration and invasion with Transwell assays and wound-healing assays. These data indicated the pro-oncogenic potential of FTX in RCC, which makes it a latent therapeutic target of RCC diagnosis and treatment in the clinic.

  13. Titanium biomaterials with complex surfaces induced aberrant peripheral circadian rhythms in bone marrow mesenchymal stromal cells.

    PubMed

    Hassan, Nathaniel; McCarville, Kirstin; Morinaga, Kenzo; Mengatto, Cristiane M; Langfelder, Peter; Hokugo, Akishige; Tahara, Yu; Colwell, Christopher S; Nishimura, Ichiro

    2017-01-01

    Circadian rhythms maintain a high level of homeostasis through internal feed-forward and -backward regulation by core molecules. In this study, we report the highly unusual peripheral circadian rhythm of bone marrow mesenchymal stromal cells (BMSCs) induced by titanium-based biomaterials with complex surface modifications (Ti biomaterial) commonly used for dental and orthopedic implants. When cultured on Ti biomaterials, human BMSCs suppressed circadian PER1 expression patterns, while NPAS2 was uniquely upregulated. The Ti biomaterials, which reduced Per1 expression and upregulated Npas2, were further examined with BMSCs harvested from Per1::luc transgenic rats. Next, we addressed the regulatory relationship between Per1 and Npas2 using BMSCs from Npas2 knockout mice. The Npas2 knockout mutation did not rescue the Ti biomaterial-induced Per1 suppression and did not affect Per2, Per3, Bmal1 and Clock expression, suggesting that the Ti biomaterial-induced Npas2 overexpression was likely an independent phenomenon. Previously, vitamin D deficiency was reported to interfere with Ti biomaterial osseointegration. The present study demonstrated that vitamin D supplementation significantly increased Per1::luc expression in BMSCs, though the presence of Ti biomaterials only moderately affected the suppressed Per1::luc expression. Available in vivo microarray data from femurs exposed to Ti biomaterials in vitamin D-deficient rats were evaluated by weighted gene co-expression network analysis. A large co-expression network containing Npas2, Bmal1, and Vdr was observed to form with the Ti biomaterials, which was disintegrated by vitamin D deficiency. Thus, the aberrant BMSC peripheral circadian rhythm may be essential for the integration of Ti biomaterials into bone.

  14. [Effects of three Wenyang Jianpi Tang on cell proliferation and apoptosis of nonalcoholic fatty liver cells].

    PubMed

    Yang, Jia-Yao; Tao, Dong-Qing; Liu, Song; Zhang, Shu; Ma, Wei; Shi, Zhao-Hong

    2017-04-01

    To investigate the effects of Sijunzi Tang, Lizhong Tang and Fuzi Lizhong Tang on the cell proliferation and apoptosis of nonalcoholic fatty liver cells through the nonalcoholic fatty liver cell model established by inducing L02 cells with oleic acid. Different concentrations of oleic acid were added into L02 cells to induce the nonalcoholic fatty liver cell model. Oil red O staining was used to observe fatty droplets of fatty liver cells. Automatic biochemical analyzer was used to detect the levels of aspartic transaminase(AST), alanine aminotransferase(ALT), total cholesterol(TC), and triglyceride(TG) in the cell supernatants. There were five groups, namely normal group, model group, model and Sijunzi Tang group, model and Lizhong Tang group, and model and Fuzi Lizhong Tang group. The cell proliferation and apoptosis of the five groups were detected by MTT colorimetry test and flow cytometer. The expressions of PCNA, cleaved caspase-3, cleaved caspase-8, cleaved caspase-9, Bax and Bcl-2 proteins of the five groups were detected by Western blot. The oil red O staining results showed that the optimum concentration of oleic acid that was used to induce nonalcoholic fatty liver cell models was 80 mg•L-1. The levels of AST, ALT, TC and TG in the nonalcoholic fatty liver cell supernatants were higher than that in normal liver cell supernatants(P<0.01). MTT colorimetry test and flow cytometer results showed that all of Sijunzi Tang, Lizhong Tang and Fuzi Lizhong Tang could effectively promote the cell proliferation, and inhibit the cellular apoptosis of nonalcoholic fatty liver cells(P<0.01). And Fuzi Lizhong Tang showed the best effect. Western blot results showed that Sijunzi Tang, Lizhong Tang and Fuzi Lizhong Tang could down-regulate the expressions of cleaved caspase-3, cleaved caspase-8, cleaved caspase-9 and Bax proteins, and up-regulate the expressions of PCNA and Bcl-2 proteins of nonalcoholic fatty liver cells. And Fuzi Lizhong Tang showed the best effect

  15. Regiospecific Synthesis of Ring A Fused Withaferin A Isoxazoline Analogues: Induction of Premature Senescence by W-2b in Proliferating Cancer Cells.

    PubMed

    Rasool, Faheem; Nayak, Debasis; Katoch, Archana; Faheem, Mir Mohd; Yousuf, Syed Khalid; Hussain, Nazar; Belawal, Chetan; Satti, N K; Goswami, Anindya; Mukherjee, Debaraj

    2017-10-23

    Induction of premature senescence represents a novel functional strategy to curb the uncontrolled proliferation of malignant cancer cells. This study unveils the regiospecific synthesis of novel isoxazoline derivatives condensed to ring A of medicinal plant product Withaferin-A. Intriguingly, the cis fused products with β-oriented hydrogen exhibited excellent cytotoxic activities against proliferating human breast cancer MCF7 and colorectal cancer HCT-116 cells. The most potent derivative W-2b triggered premature senescence along with increase in senescence-associated β-galactosidase activity, G2/M cell cycle arrest, and induction of senescence-specific marker p21 Waf1/Cip1 at its sub-toxic concentration. W-2b conferred a robust increase in phosphorylation of mammalian checkpoint kinase-2 (Chk2) in cancer cells in a dose-dependent manner. Silencing of endogenous Chk2 by siRNA divulged that the amplification of p21 expression and senescence by W-2b was Chk2-dependent. Chk2 activation (either by ectopic overexpression or through treatment with W-2b) suppressed NM23-H1 signaling axis involved in cancer cell proliferation. Finally, W-2b showed excellent in vivo efficacy with 83.8% inhibition of tumor growth at a dose of 25 mg/kg, b.w. in mouse mammary carcinoma model. Our study claims that W-2b could be a potential candidate to limit aberrant cellular proliferation rendering promising improvement in the treatment regime in cancer patients.

  16. Isl-1 down-regulates DRG cell proliferation during chicken embryo development.

    PubMed

    Chen, Dawei; Wang, Guoxin; Luo, Haoshu; Liu, Jiali; Cui, Sheng

    2010-01-01

    Protein Isl-1 RNA interference and over expression in early chicken embryo dorsal root ganglia (DRG) were used to investigate the function of Isl-1 in DRG cell proliferation. Isl-1 targeted shRNA expression vector and Isl-1 over-expression vector were transfected into chicken embryo DRG by in ovo electroporation. Then, the DRG proliferation rate was detected by BrdU immunohistochemistry. The rate of DRG cell proliferation increased after Isl-1 knock-down and decreased after Isl-1 over-expression. In this study, we found that Isl-1 negatively modulates DRG cell proliferation.

  17. ERAP1 reduces accumulation of aberrant and disulfide-linked forms of HLA-B27 on the cell surface.

    PubMed

    Tran, Tri M; Hong, Sohee; Edwan, Jehad H; Colbert, Robert A

    2016-06-01

    Endoplasmic reticulum (ER) aminopeptidase 1 (ERAP1) variants contribute to the risk of ankylosing spondylitis in HLA-B27 positive individuals, implying a disease-related interaction between these gene products. The aim of this study was to determine whether reduced ERAP1 expression would alter the cell surface expression of HLA-B27 and the formation of aberrant disulfide-linked forms that have been implicated in the pathogenesis of spondyloarthritis. ERAP1 expression was knocked down in monocytic U937 cells expressing HLA-B27 and endogenous HLA class I. The effect of ERAP1 knockdown on the accumulation HLA-B alleles (B18, B51, and B27) was assessed using immunoprecipitation, isoelectric focusing, and immunoblotting, as well as flow cytometry with antibodies specific for different forms of HLA-B27. Cell surface expression of aberrant disulfide-linked HLA-B27 dimers was assessed by immunoprecipitation and electrophoresis on non-reducing polyacrylamide gels. ERAP1 knockdown increased the accumulation of HLA-B27 on the cell surface including disulfide-linked dimers, but had no effect on levels of HLA-B18 or -B51. Antibodies with unique specificity for HLA-B27 confirmed increased cell surface expression of complexes shown previously to contain long peptides. IFN-γ treatment resulted in striking increases in the expression of disulfide-linked HLA-B27 heavy chains, even in cells with normal ERAP1 expression. Our results suggest that normal levels of ERAP1 reduce the accumulation of aberrant and disulfide-linked forms of HLA-B27 in monocytes, and thus help to maintain the integrity of cell surface HLA-B27 complexes. Published by Elsevier Ltd.

  18. ERAP1 Reduces Accumulation of Aberrant and Disulfide-Linked Forms of HLA-B27 on the Cell Surface

    PubMed Central

    Tran, Tri; Hong, Sohee; Edwan, Jehad; Colbert, Robert A.

    2016-01-01

    Objective Endoplasmic reticulum (ER) aminopeptidase 1 (ERAP1) variants contribute to the risk of ankylosing spondylitis in HLA-B27 positive individuals, implying a disease-related interaction between these gene products. The aim of this study was to determine whether reduced ERAP1 expression would alter the cell surface expression of HLA-B27 and the formation of aberrant disulfide-linked forms that have been implicated in the pathogenesis of spondyloarthritis. Methods ERAP1 expression was knocked down in monocytic U937 cells expressing HLA-B27 and endogenous HLA class I. The effect of ERAP1 knockdown on the accumulation HLA-B alleles (B18, B51, and B27) was assessed using immunoprecipitation, isoelectric focusing, and immunoblotting, as well as flow cytometry with antibodies specific for different forms of HLA-B27. Cell surface expression of aberrant disulfide-linked HLA-B27 dimers was assessed by immunoprecipitation and electrophoresis on non-reducing polyacrylamide gels. Results ERAP1 knockdown increased the accumulation of HLA-B27 on the cell surface including disulfide-linked dimers, but had no effect on levels of HLA-B18 or -B51. Antibodies with unique specificity for HLA-B27 confirmed increased cell surface expression of complexes shown previously to contain long peptides. IFN-γ treatment resulted in striking increases in the expression of disulfide-linked HLA-B27 heavy chains, even in cells with normal ERAP1 expression. Conclusions Our results suggest that normal levels of ERAP1 reduce the accumulation of aberrant and disulfide-linked forms of HLA-B27 in monocytes, and thus help to maintain the integrity of cell surface HLA-B27 complexes. PMID:27107845

  19. Down-regulation of polycystin in lymphatic malformations: possible role in the proliferation of lymphatic endothelial cells.

    PubMed

    Ren, Jian-Gang; Xia, Hou-Fu; Yang, Jie-Gang; Zhu, Jun-Yi; Zhang, Wei; Chen, Gang; Zhao, Ji-Hong; Sun, Yan-Fang; Zhao, Yi-Fang

    2017-07-01

    Lymphatic malformations (LMs) are composed of aberrant lymphatic vessels and regarded as benign growths of the lymphatic system. Recent studies have demonstrated that the mutant embryos of PKD1 and PKD2, encoding polycystin-1 (PC-1) and polycystin-2 (PC-2), respectively, result in aberrant lymphatic vessels similar to those observed in LMs. In this study, for the first time, we investigated PC-1 and PC-2 expression and assessed their roles in the development of LMs. Our results demonstrated that PC-1 and PC-2 gene and protein expressions were obviously decreased in LMs compared with normal skin tissues. In addition, the expression of phosphorylated ERK but not total ERK was up-regulated in LMs and negatively correlated with the expression of PC-1 and PC-2. Moreover, up-regulation of Ki67 was detected in LMs and positively correlated with ERK phosphorylation levels. Furthermore, cluster analysis better reflected close correlation between these signals. All of the above results provided strong evidence suggesting that the hyperactivation of the ERK pathway may be caused by down-regulation of PC-1 and PC-2 in LMs, contributing to increased proliferation of lymphatic endothelial cells in LMs. Our present study sheds light on novel potential mechanisms involved in LMs and may help to explore novel treatments for LMs. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Reduction of CD147 surface expression on primary T cells leads to enhanced cell proliferation.

    PubMed

    Biegler, Brian; Kasinrerk, Watchara

    2012-12-01

    CD147 is a ubiquitously expressed membrane glycoprotein that has numerous functional associations in health and disease. However, the molecular mechanisms by which CD147 participates in these processes are unclear. Establishing physiologically relevant silencing of CD147 in primary T cells could provide clues essential for elucidating some aspects of CD147 biology. To date, achieving the knockdown of CD147 in primary T cells has remained elusive. Utilizing RNA interference and the Nucleofector transfection system, we were able to reduce the expression of CD147 in primary T cells. Comparison of basic functions, such as proliferation and CD25 expression, were then made between control populations and populations with reduced expression. Up-regulation of CD147 was found upon T-cell activation, indicating a role in T-cell responses. To better understand the possible importance of this up-regulation, we knocked down the expression of CD147 using RNA interference. When compared to control populations the CD147 knockdown populations exhibited increased proliferation. This alteration of cell proliferation, however, was not linked to a change in CD25 expression. We achieved reduction of CD147 surface expression in primary T cells by siRNA-mediated gene silencing. Our results point to CD147 having a possible negative regulatory role in T cell-mediated immune responses.

  1. Cell proliferation is a key determinant of the outcome of FOXO3a activation

    SciTech Connect

    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.

  2. Comparison of cell repair mechanisms by means of chromosomal aberration induced by proton and gamma irradiation - preliminary results

    NASA Astrophysics Data System (ADS)

    Kowalska, A.; Czerski, K.; Kaczmarski, M.; Lewocki, M.; Masojć, B.; Łukowiak, A.

    2015-03-01

    DNA damage of peripheral blood lymphocytes exposed to gamma and proton irradiation is studied by means of chromosome aberrations to validate the efficiency of the repair mechanisms of individual cells. A new method based on an observed deviation from the Poisson statistics of the chromosome aberration number is applied for estimation of a repair factor ( RF) defined as a ratio between originally damaged cells to the amount of finally observed aberrations. The repair factors are evaluated by studying the variance of individual damage factors in a collective of healthy persons at a given dose as well as by using the chi-square analysis for the dose-effect curves. The blood samples from fifteen donors have been irradiated by Co60 gamma rays and from nine persons by 150 MeV protons with different doses up to 2 Gy. A standard extraction of lymphocyte has been used whereby dicentrics, acentrics and rings have been scored under a microscope. The RF values determined for the proton radiation are slightly larger than for gamma rays, indicating that up to 70% DNA double strand breaks can be repaired.

  3. DOCK2 regulates cell proliferation through Rac and ERK activation in B cell lymphoma

    SciTech Connect

    Wang, Lei; Nishihara, Hiroshi, E-mail: nisihara@patho2.med.hokudai.ac.jp; Kimura, Taichi

    2010-04-23

    DOCK2; a member of the CDM protein family, regulates cell motility and cytokine production through the activation of Rac in mammalian hematopoietic cells and plays a pivotal role in the modulation of the immune system. Here we demonstrated the alternative function of DOCK2 in hematopoietic tumor cells, especially in terms of its association with the tumor progression. Immunostaining for DOCK2 in 20 cases of human B cell lymphoma tissue specimens including diffuse large B cell lymphoma and follicular lymphoma revealed the prominent expression of DOCK2 in all of the lymphoma cells. DOCK2-knockdown (KD) of the B cell lymphoma cell lines,more » Ramos and Raji, using the lentiviral shRNA system presented decreased cell proliferation compared to the control cells. Furthermore, the tumor formation of DOCK2-KD Ramos cell in nude mice was significantly abrogated. Western blotting analysis and pull-down assay using GST-PAK-RBD kimeric protein suggested the presence of DOCK2-Rac-ERK pathway regulating the cell proliferation of these lymphoma cells. This is the first report to clarify the prominent role of DOCK2 in hematopoietic malignancy.« less

  4. 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.

  5. 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.

  6. Chrysin and its phosphate ester inhibit cell proliferation and induce apoptosis in Hela cells.

    PubMed

    Zhang, Ting; Chen, Xiaolan; Qu, Lingbo; Wu, Jinglan; Cui, Ran; Zhao, Yufen

    2004-12-01

    To improve the biological activities of chrysin (CR), we synthesize Diethyl Chysin-7-yl phosphate (CPE: C(19)H(19)O(7)P) and tetraethyl bis-phosphoric ester of chrysin (CP: C(23)H(28)O(10)P(2)) through a simplified Atheron-Todd reaction. The interactions of the CR and CPE with lysozyme were explored by electrospray ionization mass spectrometry (ESI) and fluorescence spectrometry method. Experimental results indicate that CPE could form the noncovalent compound with lysozyme, while the interaction of the CR with lysozyme was not detected. In addition, whether and how the compounds CPE and CP affect proliferation and apoptosis in human cervical cancer Hela cells were investigated. Moreover, the effects of CPE and CP in Hela cells were compared with that of the nonmodified CR compound. The Hela cells were co-cultured with CR, CP, and CPE as experimental groups, respectively, and corresponding control groups treated without CR, CP, and CPE. The proliferation and apoptosis were detected using MTT assay, HCl denatured-methyl green-pyronin staining, PCNA immunohistochemistry and TUNEL techniques. The cell growth IC(50), relative absorbance (RA), proliferating index (PI), PCNA-IR (immunoreactivity IR) integration value (IV), and apoptosis index (AI) were calculated and their correlation was analyzed in each group. The results show that all CR, CP, and CPE could inhibit proliferation and induce apoptosis in Hela cells. Moreover, the effects of CP and CPE were more potent than that of CR. The CP and CPE were proved to be a kind of stronger apoptosis inducers than nonphosphated CR. There was a negative correlation between proliferation and apoptosis. In conclusion, the CR, CP, and CPE could effectively inhibit growth by down-regulated expression of PCNA, and induce apoptosis in Hela cells. The efficiency of the modified CP and CPE preceded nonmodified CR compounds. The CP and CPE may be a new potential anti-cancer drug for therapy of human cervical carcinoma.

  7. Aberrant connections between climbing fibres and Purkinje cells induce alterations in the timing of an instrumental response in the rat.

    PubMed

    Gaytán-Tocavén, Lorena; López-Vázquez, Miguel Ángel; Guevara, Miguel Ángel; Olvera-Cortés, María Esther

    2017-09-01

    Cerebellar participation in timing and sensory-motor sequences has been supported by several experimental and clinical studies. A relevant role of the cerebellum in timing of conditioned responses in the range of milliseconds has been demonstrated, but less is known regarding the role of the cerebellum in supra-second timing of operant responses. A dissociated role of the cerebellum and striatum in timing in the millisecond and second range had been reported, respectively. The climbing fibre-Purkinje cell synapse is crucial in timing models; thus, the aberrant connection between these cellular elements is a suitable model for evaluating the contribution of the cerebellum in timing in the supra-second range. The aberrant connection between climbing fibres and Purkinje cells was induced by administration of the antagonist of NMDA receptors MK-801 to Sprague-Dawley rats at postnatal days 7-14. The timing of an operant response with two fixed intervals (5 and 8 s) and egocentric sequential learning was evaluated in 60-day-old adult rats. The aberrant connections caused a reduced accuracy in the timing of the instrumental response that was more evident in the 8-s interval and a reduced number of successive correct responses (responses emitted in the correct second without any other response between them) in the 8-s interval. In addition, an inability to incorporate new information in a sequence previously learned in egocentric-based sequence learning was apparent in rats with aberrant CF-PC synapses. These results support a relevant role for the cerebellum in the fine-tuning of the timing of operant responses in the supra-second range.

  8. Stimulation of cell proliferation by histamine H2 receptors in dimethylhdrazine-induced adenocarcinomata.

    PubMed

    Tutton, P J; Barkla, D H

    1978-03-01

    Cell proliferation in dimethylhydrazine-induced colonic carcinomata was stimulated by histamine and by the histamine H2 receptor agonist dimaprit and inhibited by the histamine H2 receptor antagonists Metiamide and Cimetidine but not by the histamine H1 receptor antagonist Mepyramine. In contrast histamine had no effect on colonic crypt cell proliferation in normal or dimethylhydrazine-treated rats.

  9. Simulation of proliferation and differentiation of cells in a stem-cell niche

    NASA Astrophysics Data System (ADS)

    Zhdanov, Vladimir P.

    2008-10-01

    Stem-cell niches represent microscopic compartments formed of environmental cells that nurture stem cells and enable them to maintain tissue homeostasis. The spatio-temporal kinetics of proliferation and differentiation of cells in such niches depend on the specifics of the niche structure and on adhesion and communication between cells and may also be influenced by spatial constraints on cell division. We propose a generic lattice model, taking all these factors into account, and systematically illustrate their role. The model is motivated by the experimental data available for the niches located in the subventricular zone of adult mammalian brain. The general conclusions drawn from our Monte Carlo simulations are applicable to other niches as well. One of our main findings is that the kinetics under consideration are highly stochastic due to a relatively small number of cells proliferating and differentiating in a niche and the autocatalytic character of the symmetric cell division. In particular, the kinetics exhibit huge stochastic bursts especially if the adhesion between cells is taken into account. In addition, the results obtained show that despite the small number of cells present in stem-cell niches, their arrangement can be predetermined to appreciable extent provided that the adhesion of different cells is different so that they tend to segregate.

  10. Ganoderma lucidum (Reishi) suppresses proliferation and migration of breast cancer cells via inhibiting Wnt/β-catenin signaling.

    PubMed

    Zhang, Yu

    2017-07-08

    The medical mushroom Ganoderma lucidum (Reishi), a traditional Chinese medicine, has exhibited a promising anti-cancer effect. However, the molecular mechanism of its action on cancer cells remains unclear. Aberrant activation of Wnt/β-catenin signaling pathway is the cause of many types of cancer, including breast cancer. Here we investigated the effect of Reishi on Wnt/β-catenin signaling pathway and elucidated the molecular mechanism of its function in inhibiting breast cancer cells. We found that Reishi blocked Wnt/β-catenin signaling through inhibiting the phosphorylation of Wnt co-receptor LRP6. In human (MDA-MB-231) and mouse (4T1) breast cancer cell lines, Reishi significantly decreased the phosphorylation of LRP6 and suppressed Wnt3a-activated Wnt target gene Axin2 expression. Administration of Reishi inhibited Wnt-induced hyper-proliferation of breast cancer cells and MDA-MB-231 cell migration. Our results provide evidence that Reishi suppresses breast cancer cell growth and migration through inhibiting Wnt/β-catenin signaling, indicating that Reishi may be a potential natural inhibitor for breast cancer. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Glypican-5 stimulates rhabdomyosarcoma cell proliferation by activating Hedgehog signaling

    PubMed Central

    Shi, Wen; Capurro, Mariana

    2011-01-01

    Glypican-5 (GPC5) is one of the six members of the glypican family. It has been previously reported that GPC5 stimulates the proliferation of rhabdomyosarcoma cells. In this study, we show that this stimulatory activity of GPC5 is a result of its ability to promote Hedgehog (Hh) signaling. We have previously shown that GPC3, another member of the glypican family, inhibits Hh signaling by competing with Patched 1 (Ptc1) for Hh binding. Furthermore, we showed that GPC3 binds to Hh through its core protein but not to Ptc1. In this paper, we demonstrate that GPC5 increases the binding of Sonic Hh to Ptc1. We also show that GPC5 binds to both Hh and Ptc1 through its glycosaminoglycan chains and that, unlike GPC3, GPC5 localizes to the primary cilia. Interestingly, we found that the heparan sulfate chains of GPC5 display a significantly higher degree of sulfation than those of GPC3. Based on these results, we propose that GPC5 stimulates Hh signaling by facilitating/stabilizing the interaction between Hh and Ptc1. PMID:21339334

  12. Ginger phytochemicals exhibit synergy to inhibit prostate cancer cell proliferation

    PubMed Central

    Brahmbhatt, Meera; Gundala, Sushma R.; Asif, Ghazia; Shamsi, Shahab A; Aneja, Ritu

    2014-01-01

    Dietary phytochemicals offer non-toxic therapeutic management as well as chemopreventive intervention for slow-growing prostate cancers. However, the limited success of several single-agent clinical trials suggest a paradigm shift that the health benefits of fruits and vegetables are not ascribable due to individual phytochemicals rather may be ascribed to but to synergistic interactions among them. We recently reported growth-inhibiting and apoptosis-inducing properties of ginger extract (GE) in in vitro and in vivo prostate cancer models. Nevertheless, the nature of interactions among the constituent ginger biophenolics, viz. 6-gingerol, 8-gingerol, 10-gingerol, and 6-shogoal, remains elusive. Here we show antiproliferative efficacy of the most-active GE biophenolics as single-agents and in binary combinations, and investigate the nature of their interactions using the Chou-Talalay combination-index (CI) method. Our data demonstrate that binary combinations of ginger phytochemicals synergistically inhibit proliferation of PC-3 cells with CI values ranging from 0.03-0.88. To appreciate synergy among phytochemicals present in GE, the natural abundance of ginger biophenolics was quantitated using LC-UV/MS. Interestingly, combining GE with its constituents (in particular, 6-gingerol) resulted in significant augmentation of GE’s antiproliferative activity. These data generate compelling grounds for further preclinical evaluation of GE alone and in combination with individual ginger biophenols for prostate cancer management. PMID:23441614

  13. Squamous cell carcinoma of the lung with highly proliferating fibromatosis-like stroma: a rare phenomenon.

    PubMed

    Tajima, Shogo; Takanashi, Yusuke; Koda, Kenji

    2015-01-01

    Few cases of carcinoma with exuberant stromal proliferation have been documented, apart from scirrhous carcinoma. To the best of our knowledge, previous cases of carcinoma exhibiting exuberant stromal proliferation have exclusively been reported in the thyroid gland, specifically as papillary carcinoma. The exuberant stromal proliferation has been recognized to be similar to either fibromatosis or nodular fasciitis. Herein, we report a case of a 74-year-old Japanese man whose tumor in the upper lobe of his right lung displayed highly proliferating stroma with dispersed, poorly differentiated squamous cell carcinoma nests. The stromal spindle cells (fibroblasts/myofibroblasts) had similar molecular profiles to those typically observed in fibromatosis rather than nodular fasciitis, resulting in the designation of "fibromatosis-like" stroma. The presence of carcinoma cells, along with stromal cells, expressing TGF-β in this case likely fostered continuous stromal proliferation, presumably in conjunction with the unique microenvironment in which the carcinoma cells were present.

  14. Phytochemicals attenuating aberrant activation of ß-catenin in cancer cells

    USDA-ARS?s Scientific Manuscript database

    Phytochemicals are a rich source of chemoprevention agents but their effects on modulating the Wnt/ß-catenin signaling pathway have remained largely uninvestigated. Aberrantly activated Wnt signaling can result in the abnormal stabilization of ß-catenin, a key causative step in a broad spectrum of c...

  15. The SIX1 oncoprotein mediates aberrant uterine basal cell development following neonatal exposure to diethylstilbestrol

    EPA Science Inventory

    Aberrant cellular differentiation early in life can contribute to increased cancer risk later in life. In a classic model of this effect, female mice exposed neonatally to the synthetic estrogen diethylstilbestrol (DES) have a high incidence of uterine carcinoma. These cancers ar...

  16. The SIX1 Oncoprotein Mediates Aberrant Uterine Basal Cell Development Following Neonatal Exposure to Diethylstilbestrol.

    EPA Science Inventory

    Aberrant cellular differentiation early in life can contribute to increased cancer risk later in life. In a classic model of this effect, female mice exposed on postnatal day (PND) 1-5 to the synthetic estrogen diethylstilbestrol (DES) have a high incidence of uterine carcinoma. ...

  17. Upregulation of GRAIL is associated with impaired CD4 T cell proliferation in sepsis.

    PubMed

    Aziz, Monowar; Yang, Weng-Lang; Matsuo, Shingo; Sharma, Archna; Zhou, Mian; Wang, Ping

    2014-03-01

    The loss of numbers and functionality of CD4 T cells is observed in sepsis; however, the mechanism remains elusive. Gene related to anergy in lymphocytes (GRAIL) is critical for the impairment of CD4 T cell proliferation. We therefore sought to examine the role of GRAIL in CD4 T cell proliferation during sepsis. Sepsis was induced in 10-wk-old male C57BL/6 mice by cecal ligation and puncture. Splenocytes were isolated and subjected to flow cytometry to determine CD4 T cell contents. CD4 T cell proliferation was assessed by CFSE staining, and the expression of GRAIL in splenocytes was measured by immunohistochemistry, real-time PCR, and flow cytometry. The expressions of IL-2 and early growth response-2 were determined by real-time PCR. As compared with shams, the numbers of CD4 T cells were significantly reduced in spleens. Septic CD4 T cells were less efficient in proliferation than shams. The IL-2 expression was significantly reduced, whereas the GRAIL expression was significantly increased in septic mice splenocytes as compared with shams. The small interfering RNA-mediated knockdown of GRAIL expression re-established the CD4 T cell proliferation ability ex vivo. Similarly, the treatment with recombinant murine IL-2 to the septic CD4 T cells restored their proliferation ability by downregulating GRAIL expression. Our findings reveal a novel association of the increased GRAIL expression with impaired CD4 T cell proliferation, implicating an emerging therapeutic tool in sepsis.

  18. The Long Non-Coding RNA MIR503HG Enhances Proliferation of Human ALK-Negative Anaplastic Large-Cell Lymphoma.

    PubMed

    Huang, Po-Shuan; Chung, I-Hsiao; Lin, Yang-Hsiang; Lin, Tzu-Kang; Chen, Wei-Jan; Lin, Kwang-Huei

    2018-05-14

    Anaplastic lymphoma kinase (ALK)-negative anaplastic large-cell lymphoma (ALCL) is a rare type of highly malignant, non-Hodgkin lymphoma. Currently, only a few gene rearrangements have been linked to ALK-negative ALCL progression. However, the specific molecular mechanisms underlying the growth of ALK-negative ALCL tumors remain unclear. Here, we investigated aberrantly expressed, long non-coding RNAs (lncRNAs) in ALK-negative ALCL and assessed their potential biological function. MIR503HG ( miR-503 host gene) was highly expressed in ALK-negative cell lines and was significantly upregulated in tumors in mice formed from ALK-negative ALCL cell lines. Depletion of MIR503HG suppressed tumor cell proliferation in vivo and in vitro; conversely, its overexpression enhanced tumor cell growth. MIR503HG -induced proliferation was mediated by the induction of microRNA-503 ( miR - 503 ) and suppression of Smurf2, resulting in stabilization of the tumor growth factor-β receptor (TGFBR) and enhanced tumor cell growth. Collectively, these findings support a potential role for MIR503HG in cancer cell proliferation through the miR-503 /Smurf2/TGFBR axis and indicate that MIR503HG is a potential marker in ALK-negative ALCL.

  19. 1,8-cineole inhibits both proliferation and elongation of BY-2 cultured tobacco cells.

    PubMed

    Yoshimura, Hiroko; Sawai, Yu; Tamotsu, Satoshi; Sakai, Atsushi

    2011-03-01

    Volatile monoterpenes such as 1,8-cineole inhibit the growth of Brassica campestris seedlings in a dose-dependent manner, and the growth-inhibitory effects are more severe for roots than hypocotyls. The preferential inhibition of root growth may be explained if the compounds inhibit cell proliferation more severely than cell elongation because root growth requires both elongation and proliferation of the constituent cells, whereas hypocotyl growth depends exclusively on elongation of existing cells. In order to examine this possibility, BY-2 suspension-cultured tobacco (Nicotiana tabacum) cells were treated with 1,8-cineole, and the inhibitory effects on cell proliferation and on cell elongation were assessed quantitatively. Treatment with 1,8-cineole lowered both the mitotic index and elongation of the cells in a dose-dependent manner, and the half-maximal inhibitory concentration (IC₅₀) for cell elongation was lower than that for cell proliferation. Moreover, 1,8-cineole also inhibited starch synthesis, with IC₅₀ lower than that for cell proliferation. Thus, the inhibitory effects of 1,8-cineole were not specific to cell proliferation; rather, 1,8-cineole seemed inhibitory to a variety of physiological activities when it was in direct contact with target cells. Based on these results, possible mechanisms for the mode of action of 1,8-cineole and for its preferential inhibition on root growth are discussed.

  20. Astaxanthin Inhibits Proliferation of Human Gastric Cancer Cell Lines by Interrupting Cell Cycle Progression

    PubMed Central

    Kim, Jung Ha; Park, Jong-Jae; Lee, Beom Jae; Joo, Moon Kyung; Chun, Hoon Jai; Lee, Sang Woo; Bak, Young-Tae

    2016-01-01

    Background/Aims Astaxanthin is a carotenoid pigment that has antioxidant, antitumoral, and anti-inflammatory properties. In this in vitro study, we investigated the mechanism of anticancer effects of astaxanthin in gastric carcinoma cell lines. Methods The human gastric adenocarcinoma cell lines AGS, KATO-III, MKN-45, and SNU-1 were treated with various concentrations of astaxanthin. A cell viability test, cell cycle analysis, and immunoblotting were performed. Results The viability of each cancer cell line was suppressed by astaxanthin in a dose-dependent manner with significantly decreased proliferation in KATO-III and SNU-1 cells. Astaxanthin increased the number of cells in the G0/G1 phase but reduced the proportion of S phase KATO-III and SNU-1 cells. Phosphorylated extracellular signal-regulated kinase (ERK) was decreased in an inverse dose-dependent correlation with astaxanthin concentration, and the expression of p27kip-1 increased the KATO-III and SNU-1 cell lines in an astaxanthin dose-dependent manner. Conclusions Astaxanthin inhibits proliferation by interrupting cell cycle progression in KATO-III and SNU-1 gastric cancer cells. This may be caused by the inhibition of the phosphorylation of ERK and the enhanced expression of p27kip-1. PMID:26470770

  1. Astaxanthin Inhibits Proliferation of Human Gastric Cancer Cell Lines by Interrupting Cell Cycle Progression.

    PubMed

    Kim, Jung Ha; Park, Jong-Jae; Lee, Beom Jae; Joo, Moon Kyung; Chun, Hoon Jai; Lee, Sang Woo; Bak, Young-Tae

    2016-05-23

    Astaxanthin is a carotenoid pigment that has antioxidant, antitumoral, and anti-inflammatory properties. In this in vitro study, we investigated the mechanism of anticancer effects of astaxanthin in gastric carcinoma cell lines. The human gastric adenocarcinoma cell lines AGS, KATO-III, MKN-45, and SNU-1 were treated with various concentrations of astaxanthin. A cell viability test, cell cycle analysis, and immunoblotting were performed. The viability of each cancer cell line was suppressed by astaxanthin in a dose-dependent manner with significantly decreased proliferation in KATO-III and SNU-1 cells. Astaxanthin increased the number of cells in the G0/G1 phase but reduced the proportion of S phase KATO-III and SNU-1 cells. Phosphorylated extracellular signal-regulated kinase (ERK) was decreased in an inverse dose-dependent correlation with astaxanthin concentration, and the expression of p27(kip-1) increased the KATO-III and SNU-1 cell lines in an astaxanthin dose-dependent manner. Astaxanthin inhibits proliferation by interrupting cell cycle progression in KATO-III and SNU-1 gastric cancer cells. This may be caused by the inhibition of the phosphorylation of ERK and the enhanced expression of p27(kip-1).

  2. Collective cell migration without proliferation: density determines cell velocity and wave velocity

    NASA Astrophysics Data System (ADS)

    Tlili, Sham; Gauquelin, Estelle; Li, Brigitte; Cardoso, Olivier; Ladoux, Benoît; Delanoë-Ayari, Hélène; Graner, François

    2018-05-01

    Collective cell migration contributes to embryogenesis, wound healing and tumour metastasis. Cell monolayer migration experiments help in understanding what determines the movement of cells far from the leading edge. Inhibiting cell proliferation limits cell density increase and prevents jamming; we observe long-duration migration and quantify space-time characteristics of the velocity profile over large length scales and time scales. Velocity waves propagate backwards and their frequency depends only on cell density at the moving front. Both cell average velocity and wave velocity increase linearly with the cell effective radius regardless of the distance to the front. Inhibiting lamellipodia decreases cell velocity while waves either disappear or have a lower frequency. Our model combines conservation laws, monolayer mechanical properties and a phenomenological coupling between strain and polarity: advancing cells pull on their followers, which then become polarized. With reasonable values of parameters, this model agrees with several of our experimental observations. Together, our experiments and model disantangle the respective contributions of active velocity and of proliferation in monolayer migration, explain how cells maintain their polarity far from the moving front, and highlight the importance of strain-polarity coupling and density in long-range information propagation.

  3. Mir-30d suppresses cell proliferation of colon cancer cells by inhibiting cell autophagy and promoting cell apoptosis.

    PubMed

    Zhang, Rui; Xu, Jian; Zhao, Jian; Bai, Jinghui

    2017-06-01

    MiR-30 family plays an important role in the tumorigenesis of human cancers. The aim of the study is to investigate the role of miR-30d in human colon cancer cell lines and explore the molecular mechanism in the proliferation of colon cancer cells. The expression of miR-30d was determined by real-time polymerase chain reaction assay in colon cancer cell lines (HCT15, HCT116, HT-29, DLD-1, and SW480) and the results demonstrated that miR-30d level was significantly decreased in human colon cancer cell lines, compared with normal colon epithelial cell line. Transfection with miR-30d mimics inhibited cell proliferation, and transfection with miR-30d inhibitors significantly promoted cell viability of colon cancer cells. Furthermore, TargetScan analysis predicted that miR-30d interacted with messenger RNA on its 3' untranslated region of ATG5, phosphoinositide 3-kinase, and Beclin1 to negatively regulate cell autophagy in colon cancer cells. Moreover, transfection with miR-30d induced cell arrest at G2/M phase of HT-29 cells. Overexpression of miR-30d mimics inhibited cell viability probably due to the inhibition of cell autophagy and promotion of cell apoptosis. Thus, MiR-30d inhibited cell autophagy by directly targeting messenger RNA of ATG5, phosphoinositide 3-kinase, and Beclin1 and promoted cell apoptosis of human colon cancer cells. It is helpful to clarify the function of miR-30d in tumorigenesis of human cancers.

  4. [Role of connective tissue growth factor (CTGF) in proliferation and migration of pancreatic cancer cells].

    PubMed

    Bai, Yu-chun; Kang, Quan; Luo, Qing; Wu, Dao-qi; Ye, Wei-xia; Lin, Xue-mei; Zhao, Yong

    2011-10-01

    To explore the expression of connective tissue growth factor (CTGF) in pancreatic cancer and its influence on the proliferation and migration of cancer cells. The expression of CTGF in pancreatic cell line PANC-1 cells was analyzed by real-time PCR and in pancreatic carcinoma (50 cases) tissues by immunohistochemistry. The ability of proliferation and migration in vitro of PANC-1 cells was tested by MTT assay, scratch test and Boyden chamber test after the CTGF gene was overexpressed by Ad5-CTGF or silenced with Ad5-siCTGF transfection. CTGF was overexpressed in both pancreatic cancer cells and tissues. Overxpression of CTGF leads to increased proliferation and migration of PANC-1 cells. The CTGF-transfected PANC-1 cells showed apparent stronger proliferation ability and scratch-repair ability than that of empty vector controls. The results of Boyden chamber test showed that there were 34 cells/field (200× magnificantion) of the CTGF-transfected overexpressing cells, much more than the 11 cells/field of the empty vector control cells; and 6 cells/microscopic field of the Ad5-siCTGF-transfected silenced cells, much less than the 15 cells/field of the control cells. CTGF is overexpressed in both pancreatic cancer cells in vitro and in vivo, indicating that it may play an important role in the cell proliferation and migration in pancreatic cancer.

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

    SciTech Connect

    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 m