YThe BigH3 Tumor Suppressor Gene in Radiation-Induced Malignant Transformation of Human Bronchial Epithelial Cells

NASA Astrophysics Data System (ADS)

Zhao, Y.; Shao, G.; Piao, C.; Hei, T.

Carcinogenesis is a multi-stage process with sequences of genetic events governing the phenotypic expression of a series of transformation steps leading to the development of metastatic cancer Previous studies from this laboratory have identified a 7 fold down- regulation of the novel tumor suppressor Big-h3 among radiation induced tumorigenic BEP2D cells Furthermore ectopic re-expression of this gene suppresses tumorigenic phenotype and promotes the sensitivity of these tumor cells to etoposide-induced apoptosis To extend these studies using a genomically more stable bronchial cell line we ectopically expresses the catalytic subunit of telomerase hTERT in primary human small airway epithelial SAE cells and generated several clonal cell lines that have been continuously in culture for more than 250 population doublings and are considered immortal Comparably-treated control SAE cells infected with only the viral vector senesced after less than 10 population doublings The immortalized clones demonstrated anchorage dependent growth and are non-tumorigenic in nude mice These cells show no alteration in the p53 gene but a decrease in p16 expression Exponentially growing SAEh cells were exposed to graded doses of 1 GeV nucleon of 56 Fe ions accelerated at the Brookhaven National Laboratory Irradiated cells underwent gradual phenotypic alterations after extensive in vitro cultivation Transformed cells developed through a series of successive steps before becoming anchorage independent in semisolid medium These findings indicate

miR-130a activates apoptotic signaling through activation of caspase-8 in taxane-resistant prostate cancer cells.

PubMed

Fujita, Yasunori; Kojima, Toshio; Kawakami, Kyojiro; Mizutani, Kosuke; Kato, Taku; Deguchi, Takashi; Ito, Masafumi

2015-10-01

The acquisition of drug resistance is one of the most malignant phenotypes of cancer and identification of its therapeutic target is a prerequisite for the development of novel therapy. MicroRNAs (miRNAs) have been implicated in various types of cancer and proposed as potential therapeutic targets for patients. In the present study, we aimed to identify miRNA that could serve as a therapeutic target for taxane-resistant prostate cancer. In order to identify miRNAs related to taxane-resistance, miRNA profiling was performed using prostate cancer PC-3 cells and paclitaxel-resistant PC-3 cell lines established from PC-3 cells. Microarray analysis of mRNA expression was also conducted to search for potential target genes of miRNA. Luciferase reporter assay was performed to examine miRNA binding to the 3'-UTR of target genes. The effects of ectopic expression of miRNA on cell growth, tubulin polymerization, drug sensitivity, and apoptotic signaling pathway were investigated in a paclitaxel-resistant PC-3 cell line. The expression of miR-130a was down-regulated in all paclitaxel-resistant cell lines compared with parental PC-3 cells. Based on mRNA microarray analysis and luciferase reporter assay, we identified SLAIN1 as a direct target gene for miR-130a. Transfection of a miR-130a precursor into a paclitaxel-resistant cell line suppressed cell growth and increased the sensitivity to paclitaxel. Lastly, ectopic expression of miR-130a did not affect the polymerized tubulin level, but activated apoptotic signaling through activation of caspase-8. Our results suggested that reduced expression of miR-130a may be involved in the paclitaxel-resistance and that miR-130a could be a therapeutic target for taxane-resistant prostate cancer patients. © 2015 Wiley Periodicals, Inc.

Lactational ectopic breast tissue of the vulva: case report and brief historical review.

PubMed

Pieh-Holder, Kelly L

2013-04-01

Ectopic breast tissue is defined as glands of breast tissue located outside of the normal anatomic breasts. Historically, ectopic breast tissue has been thought to arise from a remnant of the embryonic mammary ridge along the "milk line" or the midaxillary line from the axilla to the groin, including the vulvar region. Extramammary tissue displays the same pathologic and physiologic changes as normal breast tissue and is often discovered in multiparous women as the result of swelling from lactational activity. We present a case report of a gravid patient with lactating vulvar mass and a brief historical perspective of vulvar ectopic breast tissue.

Transcriptional deregulation of oncogenic myocyte enhancer factor 2C in T-cell acute lymphoblastic leukemia.

PubMed

Nagel, Stefan; Venturini, Letizia; Meyer, Corinna; Kaufmann, Maren; Scherr, Michaela; Drexler, Hans G; Macleod, Roderick A F

2011-02-01

Myocyte enhancer factor 2C (MEF2C) encodes a transcription factor which is ectopically expressed in T-cell acute lymphoblastic leukemia (T-ALL) cell lines, deregulated directly by ectopically expressed homeodomain protein NKX2-5 or by loss of promoter regions via del(5)(q14). Here, we analyzed the MEF2C 5'-region, thus identifying potential regulatory binding sites for GFI1B, basic helix-loop-helix proteins, STAT5, and HOXA9/HOXA10. Chromatin immunoprecipitation and overexpression analyses demonstrated direct activation by GFI1B and LYL1 and inhibition by STAT5. HOXA9/HOXA10 activated expression of NMYC which in turn mediated MEF2C repression, indicating an indirect mode of regulation via NMYC interactor (NMI) and STAT5. Lacking comma: Chromosomal deletion of the STAT5 binding site in LOUCY cells reduced protein levels of STAT5 in some MEF2C-positve T-ALL cell lines, and the presence of inhibitory IL7-JAK-STAT5 signaling highlighted the repressive impact of this factor in MEF2C regulation. Taken together, our results indicate that the expression of MEF2C in T-ALL cells is principally deregulated via activating leukemic transcription factors GFI1B or NKX2-5 and by escaping inhibitory developmental STAT5 signaling.

miR-221 and miR-222 expression affects the proliferation potential of human prostate carcinoma cell lines by targeting p27Kip1.

PubMed

Galardi, Silvia; Mercatelli, Neri; Giorda, Ezio; Massalini, Simone; Frajese, Giovanni Vanni; Ciafrè, Silvia Anna; Farace, Maria Giulia

2007-08-10

MicroRNAs are short regulatory RNAs that negatively modulate protein expression at a post-transcriptional level and are deeply involved in the pathogenesis of several types of cancers. Here we show that miR-221 and miR-222, encoded in tandem on chromosome X, are overexpressed in the PC3 cellular model of aggressive prostate carcinoma, as compared with LNCaP and 22Rv1 cell line models of slowly growing carcinomas. In all cell lines tested, we show an inverse relationship between the expression of miR-221 and miR-222 and the cell cycle inhibitor p27(Kip1). We recognize two target sites for the microRNAs in the 3' untranslated region of p27 mRNA, and we show that miR-221/222 ectopic overexpression directly results in p27 down-regulation in LNCaP cells. In those cells, we demonstrate that the ectopic overexpression of miR-221/222 strongly affects their growth potential by inducing a G(1) to S shift in the cell cycle and is sufficient to induce a powerful enhancement of their colony-forming potential in soft agar. Consistently, miR-221 and miR-222 knock-down through antisense LNA oligonucleotides increases p27(Kip1) in PC3 cells and strongly reduces their clonogenicity in vitro. Our results suggest that miR-221/222 can be regarded as a new family of oncogenes, directly targeting the tumor suppressor p27(Kip1), and that their overexpression might be one of the factors contributing to the oncogenesis and progression of prostate carcinoma through p27(Kip1) down-regulation.

Growth inhibition mediated by PSP94 or CRISP-3 is prostate cancer cell line specific.

PubMed

Pathak, Bhakti R; Breed, Ananya A; Nakhawa, Vaishali H; Jagtap, Dhanashree D; Mahale, Smita D

2010-09-01

The prostate secretory protein of 94 amino acids (PSP94) has been shown to interact with cysteine-rich secretory protein 3 (CRISP-3) in human seminal plasma. Interestingly, PSP94 expression is reduced or lost in the majority of the prostate tumours, whereas CRISP-3 expression is upregulated in prostate cancer compared with normal prostate tissue. To obtain a better understanding of the individual roles these proteins have in prostate tumourigenesis and the functional relevance of their interaction, we ectopically expressed either PSP94 or CRISP-3 alone or PSP94 along with CRISP-3 in three prostate cell lines (PC3, WPE1-NB26 and LNCaP) and performed growth inhibition assays. Reverse transcription-polymerase chain reaction and Western blot analysis were used to screen prostate cell lines for PSP94 and CRISP-3 expression. Mammalian expression constructs for human PSP94 and CRISP-3 were also generated and the expression, localization and secretion of recombinant protein were assayed by transfection followed by Western blot analysis and immunofluorescence assay. The effect that ectopic expression of PSP94 or CRISP-3 had on cell growth was studied by clonogenic survival assay following transfection. To evaluate the effects of co-expression of the two proteins, stable clones of PC3 that expressed PSP94 were generated. They were subsequently transfected with a CRISP-3 expression construct and subjected to clonogenic survival assay. Our results showed that PSP94 and CRISP-3 could each induce growth inhibition in a cell line specific manner. Although the growth of CRISP-3-positive cell lines was inhibited by PSP94, growth inhibition mediated by CRISP-3 was not affected by the presence or absence of PSP94. This suggests that CRISP-3 may participate in PSP94-independent activities during prostate tumourigenesis.

Cell type-specific roles of Jak3 in IL-2-induced proliferative signal transduction

PubMed Central

Fujii, Hodaka

2007-01-01

Binding of IL-2 to its specific receptor induces activation of two members of Jak family protein tyrosine kinases, Jak1 and Jak3. An IL-2R-reconstituted NIH 3T3 fibroblast cell line proliferates in response to IL-2 only when hematopoietic lineage-specific Jak3 is ectopically expressed. However, the mechanism of Jak3-dependent proliferation in the fibroblast cell line is not known. Here, I showed that Jak3 expression is dispensable for IL-2-induced activation of Jak1 and Stat proteins and expression of nuclear proto-oncogenes in the IL-2R-reconstituted fibroblast cell line. However, Jak3 expression markedly enhanced these IL-2-induced signaling events. In contrast, Jak3 expression was essential for induction of cyclin genes involved in the G1-S transition. These data suggest a critical role of Jak3 in IL-2 signaling in the fibroblast cell line and may provide further insight into the cell type-specific mechanism of cytokine signaling. PMID:17266928

Ectopic Atoh1 expression drives Merkel cell production in embryonic, postnatal and adult mouse epidermis.

PubMed

Ostrowski, Stephen M; Wright, Margaret C; Bolock, Alexa M; Geng, Xuehui; Maricich, Stephen M

2015-07-15

Merkel cells are mechanosensitive skin cells whose production requires the basic helix-loop-helix transcription factor Atoh1. We induced ectopic Atoh1 expression in the skin of transgenic mice to determine whether Atoh1 was sufficient to create additional Merkel cells. In embryos, ectopic Atoh1 expression drove ectopic expression of the Merkel cell marker keratin 8 (K8) throughout the epidermis. Epidermal Atoh1 induction in adolescent mice similarly drove widespread K8 expression in glabrous skin of the paws, but in the whisker pads and body skin ectopic K8+ cells were confined to hair follicles and absent from interfollicular regions. Ectopic K8+ cells acquired several characteristics of mature Merkel cells in a time frame similar to that seen during postnatal development of normal Merkel cells. Although ectopic K8+ cell numbers decreased over time, small numbers of these cells remained in deep regions of body skin hair follicles at 3 months post-induction. In adult mice, greater numbers of ectopic K8+ cells were created by Atoh1 induction during anagen versus telogen and following disruption of Notch signaling by conditional deletion of Rbpj in the epidermis. Our data demonstrate that Atoh1 expression is sufficient to produce new Merkel cells in the epidermis, that epidermal cell competency to respond to Atoh1 varies by skin location, developmental age and hair cycle stage, and that the Notch pathway plays a key role in limiting epidermal cell competency to respond to Atoh1 expression. © 2015. Published by The Company of Biologists Ltd.

Immortalization of Human Fetal Hepatocyte by Ectopic Expression of Human Telomerase Reverse Transcriptase, Human Papilloma Virus (E7) and Simian Virus 40 Large T (SV40 T) Antigen Towards Bioartificial Liver Support.

PubMed

Giri, Shibashish; Bader, Augustinus

2014-09-01

Generation of genetically stable and non-tumoric immortalization cell line from primary cells would be enormously useful for research and therapeutic purposes, but progress towards this goal has so far been limited. It is now universal acceptance that immortalization of human fetal hepatocytes based on recent advances of telomerase biology and oncogene, lead to unlimited population doubling could be the possible source for bioartificial liver device. Immortalization of human fetal hepatocytes cell line by ectopic expression of human telomerase reverse transcriptase (hTERT), human papilloma virus gene (E7) and simian virus 40 large T (SV40 T) antigens is main goal of present study. We used an inducible system containing human telomerase and E7, both of which are cloned into responder constructs controlled by doxycycline transactivator. We characterized the immortalized human fetal hepatocyte cells by analysis of green fluorescent cells (GFP) positive cells using flow cytometry (FACs) cell sorting and morphology, proliferative rate and antigen expression by immunohistochemical analysis. In addition to we analysized lactate formation, glucose consumption, albumin secretion and urea production of immortalized human fetal hepatocyte cells. After 25 attempts for transfection of adult primary hepatocytes by human telomerase and E7 to immortalize them, none of the transfection systems resulted in the production of a stable, proliferating cell line. Although the transfection efficiency was more than 70% on the first day, the vast majority of the transfected hepatocytes lost their signal within the first 5-7 days. The remaining transfected hepatocytes persisted for 2-4 weeks and divided one or two times without forming a clone. After 10 attempts of transfection human fetal hepatocytes using the same transfection system, we obtained one stable human fetal hepatocytes cell line which was able albumin secretion urea production and glucose consumption. We established a conditional human fetal hepatocytes cell line with mesenchymal characteristics. Thus immortalization of human fetal hepatocytes cell line by telomerase biology offers a great challenge to examine basic biological mechanisms which are directly related to human and best cell source having unlimited population doubling for bioartificial support without any risk of replicative senescence and pathogenic risks.

Characterization of the synthesis and expression of the GTA-kinase from transformed and normal rodent cells.

PubMed

Kerr, M; Fischer, J E; Purushotham, K R; Gao, D; Nakagawa, Y; Maeda, N; Ghanta, V; Hiramoto, R; Chegini, N; Humphreys-Beher, M G

1994-08-02

The murine transformed cell line YC-8 and beta-adrenergic receptor agonist (isoproternol) treated rat and mouse parotid gland acinar cells ectopically express cell surface beta 1-4 galactosyltransferase during active proliferation. This activity is dependent upon the expression of the GTA-kinase (p58) in these cells. Using total RNA, cDNA clones for the protein coding region of the kinase were isolated by reverse transcriptase-PCR cloning. DNA sequence analysis failed to show sequence differences with the normal homolog from mouse cells although Southern blot analysis of YC-8, and a second cell line KI81, indicated changes in the restriction enzyme digestion profile relative to murine cell lines which do not express cell surface galactosyltransferase. The rat cDNA clone from isoproterenol-treated salivary glands showed a high degree of protein and nucleic acid sequence homology to the GTA-kinase from both murine and human sources. Northern blot analysis of YC-8 and a control cell line LSTRA revealed the synthesis of a major 3.0 kb mRNA from both cell lines plus the unique expression of a 4.5 kb mRNA in the YC-8 cells. Reverse transcriptase-PCR of LSTRA and YC-8 confirmed the increased steady state levels of the GTA-kinase mRNA in YC-8. In the mouse, induction of cell proliferation by isoproterenol resulted in a 50-fold increase in steady state mRNA levels for the kinase over the low level of expression in quiescent cells. Expression of the rat 3' untranslated region in rat parotid cells in vitro led to an increased rate of DNA synthesis, cell number an ectopic expression of cell surface galactosyltransferase in the sense orientation. Antisense expression or vector alone did not alter growth characteristics of acinar cells. A polyclonal antibody monospecific to a murine amino terminal peptide sequence revealed a uniform distribution of GTA-kinase over the cytoplasm of acinar and duct cells of control mouse parotid glands. However, upon growth stimulation, kinase was detected primarily in a perinuclear and nuclear immunostaining pattern. Western blot analysis confirmed a translocation from a cytoplasmic localization in both LSTRA and quiescent salivary cells to a membrane-associated localization in YC-8 and proliferating salivary cells.

MicroRNA profiling of novel African American and Caucasian Prostate Cancer cell lines reveals a reciprocal regulatory relationship of miR-152 and DNA methyltranferase 1

PubMed Central

Theodore, Shaniece C.; Davis, Melissa; Zhao, Fu; Wang, Honghe; Chen, Dongquan; Rhim, Johng; Dean-Colomb, Windy; Turner, Timothy; Ji, Weidong; Zeng, Guohua; Grizzle, William; Yates, Clayton

2014-01-01

miRNA expression in African American compared to Caucasian PCa patients has not been widely explored. Herein, we probed the miRNA expression profile of novel AA and CA derived prostate cancer cell lines. We found a unique miRNA signature associated with AA cell lines, independent of tumor status. Evaluation of the most differentially expressed miRNAs showed that miR-132, miR-367b, miR-410, and miR-152 were decreased in more aggressive cells, and this was reversed after treatment of the cells with 5-aza-2′-deoxycytidine. Sequencing of the miR-152 promoter confirmed that it was highly methylated. Ectopic expression of miR-152 resulted in decreased growth, migration, and invasion. Informatics analysis of a large patient cohort showed that decreased miR-152 expression correlated with increased metastasis and a decrease in biochemical recurrence free survival. Analysis of 39 prostate cancer tissues with matched controls (20 AA and 19 CA), showed that 50% of AA patients had statistically significant lower miR-152 expression compared to only 35% of CA patients. Ectopic expression of miR-152 in LNCaP, PC-3, and MDA-PCa-2b cells down-regulated DNA (cytosine-5)-methyltransferase 1 (DNMT1) through direct binding in the DNMT1 3'UTR. There appeared to be a reciprocal regulatory relationship of miR-152/DNMT1 expression, as cells treated with siRNA DNMT1 caused miR-152 to be re-expressed in all cell lines. In summary, these results demonstrate that epigenetic regulation of miR-152/DNMT1 may play an important role in multiple events that contribute to the aggressiveness of PCa tumors, with an emphasis on AA PCa patients. PMID:25004396

Spi-C has opposing effects to PU.1 on gene expression in progenitor B cells.

PubMed

Schweitzer, Brock L; Huang, Kelly J; Kamath, Meghana B; Emelyanov, Alexander V; Birshtein, Barbara K; DeKoter, Rodney P

2006-08-15

The Ets transcription factor Spi-C, expressed in B cells and macrophages, is closely related to PU.1 and has the ability to recognize the same DNA consensus sequence. However, the function of Spi-C has yet to be determined. The purpose of this study is to further examine Spi-C activity in B cell development. First, using retroviral vectors to infect PU.1(-/-) fetal liver progenitors, Spi-C was found to be inefficient at inducing cytokine-dependent proliferation and differentiation of progenitor B (pro-B) cells or macrophages relative to PU.1 or Spi-B. Next, Spi-C was ectopically expressed in fetal liver-derived, IL-7-dependent pro-B cell lines. Wild-type (WT) pro-B cells ectopically expressing Spi-C (WT-Spi-C) have several phenotypic characteristics of pre-B cells such as increased CD25 and decreased c-Kit surface expression. In addition, WT-Spi-C pro-B cells express increased levels of IgH sterile transcripts and reduced levels of expression and transcription of the FcgammaRIIb gene. Gel-shift analysis suggests that Spi-C, ectopically expressed in pro-B cells, can bind PU.1 consensus sites in the IgH intronic enhancer and FcgammaRIIb promoter. Transient transfection analysis demonstrated that PU.1 functions to repress the IgH intronic enhancer and activate the FcgammaRIIb promoter, while Spi-C opposes these activities. WT-Spi-C pro-B cells have reduced levels of dimethylation on lysine 9 of histone H3 within the IgH 3' regulatory region, indicating that Spi-C can contribute to removal of repressive features in the IgH locus. Overall, these studies suggest that Spi-C may promote B cell differentiation by modulating the activity of PU.1-dependent genes.

Ectopic expression of a novel CD22 splice-variant regulates survival and proliferation in malignant T cells from cutaneous T cell lymphoma (CTCL) patients

PubMed Central

Bagdonaite, Ieva; Wandall, Hans H.; Litvinov, Ivan V.; Nastasi, Claudia; Becker, Jürgen C.; Dabelsteen, Sally; Geisler, Carsten; Bonefeld, Charlotte M.; Zhang, Qian; Wasik, Mariusz A.; Zhou, Youwen; Sasseville, Denis; Ødum, Niels; Woetmann, Anders

2015-01-01

CD22 is a member of the Sialic acid-binding Ig-like lectin (Siglec) family of lectins described to be exclusively present in B lymphocytes and B cell-derived neoplasms. Here, we describe a novel splice form of CD22 (designated CD22ΔN), which lacks the N-terminal domain as demonstrated by exon-specific RT-PCR and differential recognition by anti-CD22 antibodies. Importantly, CD22ΔN mRNA is expressed in skin lesions from 39 out of 60 patients with cutaneous T cell lymphoma (CTCL), whereas few patients (6 out of 60) expresses full-length, wild type CD22 (CD22wt). In addition, IHC staining of tumor biopsies confirmed the expression of CD22 in CD4+ T cells. Moreover, four out of four malignant T cell lines express CD22: Two cell lines express CD22ΔN (MyLa2059 and PB2B) and two express CD22wt (MAC-1 and MAC-2A). siRNA-mediated silencing of CD22 impairs proliferation and survival of malignant T cells, demonstrating a functional role for both CD22ΔN and CD22wt in these cells. In conclusion, we provide the first evidence for an ectopic expression of CD22 and a novel splice variant regulating malignant proliferation and survival in CTCL. Analysis of expression and function of CD22 in cutaneous lymphomas may form the basis for development of novel targeted therapies for our patients. PMID:25957418

Ectopic expression of a novel CD22 splice-variant regulates survival and proliferation in malignant T cells from cutaneous T cell lymphoma (CTCL) patients.

PubMed

Bagdonaite, Ieva; Wandall, Hans H; Litvinov, Ivan V; Nastasi, Claudia; Becker, Jürgen C; Dabelsteen, Sally; Geisler, Carsten; Bonefeld, Charlotte M; Zhang, Qian; Wasik, Mariusz A; Zhou, Youwen; Sasseville, Denis; Ødum, Niels; Woetmann, Anders

2015-06-10

CD22 is a member of the Sialic acid-binding Ig-like lectin (Siglec) family of lectins described to be exclusively present in B lymphocytes and B cell-derived neoplasms. Here, we describe a novel splice form of CD22 (designated CD22∆N), which lacks the N-terminal domain as demonstrated by exon-specific RT-PCR and differential recognition by anti-CD22 antibodies. Importantly, CD22∆N mRNA is expressed in skin lesions from 39 out of 60 patients with cutaneous T cell lymphoma (CTCL), whereas few patients (6 out of 60) expresses full-length, wild type CD22 (CD22wt). In addition, IHC staining of tumor biopsies confirmed the expression of CD22 in CD4+ T cells. Moreover, four out of four malignant T cell lines express CD22: Two cell lines express CD22∆N (MyLa2059 and PB2B) and two express CD22wt (MAC-1 and MAC-2A). siRNA-mediated silencing of CD22 impairs proliferation and survival of malignant T cells, demonstrating a functional role for both CD22∆N and CD22wt in these cells.In conclusion, we provide the first evidence for an ectopic expression of CD22 and a novel splice variant regulating malignant proliferation and survival in CTCL. Analysis of expression and function of CD22 in cutaneous lymphomas may form the basis for development of novel targeted therapies for our patients.

Ectopic KNOX Expression Affects Plant Development by Altering Tissue Cell Polarity and Identity[OPEN

PubMed Central

Rebocho, Alexandra B.

2016-01-01

Plant development involves two polarity types: tissue cell (asymmetries within cells are coordinated across tissues) and regional (identities vary spatially across tissues) polarity. Both appear altered in the barley (Hordeum vulgare) Hooded mutant, in which ectopic expression of the KNOTTED1-like Homeobox (KNOX) gene, BKn3, causes inverted polarity of differentiated hairs and ectopic flowers, in addition to wing-shaped outgrowths. These lemma-specific effects allow the spatiotemporal analysis of events following ectopic BKn3 expression, determining the relationship between KNOXs, polarity, and shape. We show that tissue cell polarity, based on localization of the auxin transporter SISTER OF PINFORMED1 (SoPIN1), dynamically reorients as ectopic BKn3 expression increases. Concurrently, ectopic expression of the auxin importer LIKE AUX1 and boundary gene NO APICAL MERISTEM is activated. The polarity of hairs reflects SoPIN1 patterns, suggesting that tissue cell polarity underpins oriented cell differentiation. Wing cell files reveal an anisotropic growth pattern, and computational modeling shows how polarity guiding growth can account for this pattern and wing emergence. The inverted ectopic flower orientation does not correlate with SoPIN1, suggesting that this form of regional polarity is not controlled by tissue cell polarity. Overall, the results suggest that KNOXs trigger different morphogenetic effects through interplay between tissue cell polarity, identity, and growth. PMID:27553356

Establishment and characterization of a goat synovial membrane cell line susceptible to small ruminant lentivirus infection.

PubMed

Rolland, Morgane; Chauvineau, Cécile; Valas, Stephen; Mamoun, Robert Z; Perrin, Gérard

2004-06-15

Primary goat synovial membrane (GSM) cells are widely used to study small ruminant lentiviruses (SRLV), i.e. maedi visna virus (MVV) and caprine arthritis-encephalitis virus (CAEV), but their limited life-span of 15-20 passages in vitro is problematic. Here, we report that ectopic expression of the catalytic subunit of human telomerase (hTERT) was sufficient to immortalize primary GSM cells. Cultures of hTERT-transfected GSM cells have been passaged for 2 years without showing any phenotypic difference from the original primary GSM cells. The hTERT-transfected cells continued to grow beyond a population doubling number of 250, while no net telomere lengthening was observed for these cells. Moreover, the immortalized GSM cells were susceptible to infection by both CAEV and MVV and were able to propagate theses viruses. Such cell line provides a useful source of standard and robust cells for both research and veterinary purposes.

Vasostatin-2 inhibits cell proliferation and adhesion in vascular smooth muscle cells, which are associated with the progression of atherosclerosis

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

Hou, Jianghong, E-mail: jianghonghou@163.com; Xue, Xiaolin; Li, Junnong

2016-01-22

Recently, the serum expression level of vasostatin-2 was found to be reduced and is being studied as an important indicator to assess the presence and severity of coronary artery disease; the functional properties of vasostatin-2 and its relationship with the development of atherosclerosis remains unclear. In this study, we attempted to detect the expression of vasostatin-2 and its impact on human vascular smooth muscle cells (VSMCs). Quantitative real-time PCR (qRT-PCR) and western blot were used to assess the expression level of vasostatin-2 in VSMCs between those from atherosclerosis and disease-free donors; we found that vasostatin-2 was significantly down-regulated in atherosclerosismore » patient tissues and cell lines. In addition, the over-expression of vasostatin-2 apparently inhibits cell proliferation and migration in VSMCs. Gain-of-function in vitro experiments further show that vasostatin-2 over-expression significantly inhibits inflammatory cytokines release in VSMCs. In addition, cell adhesion experimental analysis showed that soluble adhesion molecules (sICAM-1, sVCAM-1) had decreased expression when vasostatin-2 was over-expressed in VSMCs. Therefore, our results indicate that vasostatin-2 is an atherosclerosis-related factor that can inhibit cell proliferation, inflammatory response and cell adhesion in VSMCs. Taken together, our results indicate that vasostatin-2 could serve as a potential diagnostic biomarker and therapeutic option for human atherosclerosis in the near future. - Highlights: • Vasostatin-2 levels were down-regulated in atherosclerosis patient tissues and VSMCs. • Ectopic expression of vasostatin-2 directly affects cell proliferation and migration in vitro. • Ectopic expression of vasostatin-2 protein affects pro-inflammatory cytokines release in VSMCs. • Ectopic expression of vasostatin-2 protein affects cell adhesion in VSMCs.« less

The Role of SncN and Ski in Mammary Epithelial Cell Transformation

DTIC Science & Technology

2005-07-01

cellular activities through the Smad proteins. Upon phosphorylation by the active TGFβ receptor kinases, Smad2 and Smad3 oligomerize with Smad4, translocate...sequence in sense and antisense orientation with an intervening linker . Primer pairs were designed to generate single-strand overhangs upon annealing...nuclear protein, based on studies of ectopically expressed SnoN and endogenous SnoN in cancer cell lines. In the nucleus, SnoN binds to Smad2, Smad3 , and

Comparing the efficacy of photodynamic and sonodynamic therapy in non-melanoma and melanoma skin cancer.

PubMed

McEwan, Conor; Nesbitt, Heather; Nicholas, Dean; Kavanagh, Oisin N; McKenna, Kevin; Loan, Philip; Jack, Iain G; McHale, Anthony P; Callan, John F

2016-07-01

Sonodynamic therapy (SDT) involves the activation of a non-toxic sensitiser drug using low-intensity ultrasound to produce cytotoxic reactive oxygen species (ROS). Given the low tissue attenuation of ultrasound, SDT provides a significant benefit over the more established photodynamic therapy (PDT) as it enables activation of sensitisers at a greater depth within human tissue. In this manuscript, we compare the efficacy of aminolevulinic acid (ALA) mediated PDT and SDT in a squamous cell carcinoma (A431) cell line as well as the ability of these treatments to reduce the size of A431 ectopic tumours in mice. Similarly, the relative cytotoxic ability of Rose Bengal mediated PDT and SDT was investigated in a B16-melanoma cell line and also in a B16 ectopic tumour model. The results reveal no statistically significant difference in efficacy between ALA mediated PDT or SDT in the non-melanoma model while Rose Bengal mediated SDT was significantly more efficacious than PDT in the melanoma model. This difference in efficacy was, at least in part, attributed to the dark pigmentation of the melanoma cells that effectively filtered the excitation light preventing it from activating the sensitiser while the use of ultrasound circumvented this problem. These results suggest SDT may provide a better outcome than PDT when treating highly pigmented cancerous skin lesions. Copyright © 2016. Published by Elsevier Ltd.

Ectopic transgene expression in the retina of four transgenic mouse lines

PubMed Central

Gábriel, Robert; Erdélyi, Ferenc; Szabó, Gábor; Lawrence, J. Josh

2017-01-01

Retinal expression of transgenes was examined in four mouse lines. Two constructs were driven by the choline acetyltransferase (ChAT) promoter: green fluorescent protein conjugated to tau protein (tau-GFP) or cytosolic yellow fluorescent protein (YFP) generated through CRE recombinase-induced expression of Rosa26 (ChAT-CRE/ Rosa26YFP). Two other constructs targeted inhibitory interneurons: GABAergic horizontal and amacrine cells identified by glutamic acid decarboxylase (GAD65-GFP) or parvalbumin (PV) cells (PV-CRE/Rosa26YFP). Animals were transcardially perfused and retinal sections prepared. Antibodies against PV, calretinin (CALR), calbindin (CALB), and tyrosine hydroxylase (TH) were used to counterstain transgene-expressing cells. In PVxRosa and ChAT-tauGFP constructs, staining appeared in vertically oriented row of processes resembling Müller cells. In the ChATxRosa construct, populations of amacrine cells and neurons in the ganglion cell layer were labeled. Some cones also exhibited GFP fluorescence. CALR, PV and TH were found in none of these cells. Occasionally, we found GFP/ CALR and GFP/PV double-stained cells in the ganglion cell layer (GCL). In the GAD65-GFP construct, all layers of the neuroretina were labeled, except photoreceptors. Not all horizontal cells expressed GFP. We did not find GFP/TH double-labeled cells and GFP was rarely present in CALR-and CALB-containing cells. Many PV-positive neurons were also labeled for GFP, including small diameter amacrines. In the GCL, single labeling for GFP and PV was ascertained, as well as several CALR/PV double-stained neurons. In the GCL, cells triple labeled with GFP/CALR/ CALB were sparse. In conclusion, only one of the four transgenic constructs exhibited an expression pattern consistent with endogenous retinal protein expression, while the others strongly suggested ectopic gene expression. PMID:26563404

The Effect of Recombinant Tyrosine Hydroxylase Expression on the Neurogenic Differentiation Potency of Mesenchymal Stem Cells

PubMed Central

Duruksu, Gokhan; Karaoz, Erdal

2018-01-01

Objective Tyrosine hydroxylase (TH) is a rate-limiting enzyme in dopamine synthesis, making the enhancement of its activity a target for ensuring sufficient dopamine levels. Rat bone marrow mesenchymal stem cells (rBM-MSCs) are known to synthesize TH after differentiating into neuronal cells through chemical induction, but the effect of its ectopic expression on these cells has not yet been determined. This study investigated the effects of ectopic recombinant TH expression on the stemness characteristics of rBM-MSCs. Methods After cloning, a cell line with stable TH expression was maintained, and the proliferation, the gene expression profile, and differentiation potential of rBM-MSCs were analyzed. Analysis of the cells showed an increment in the proliferation rate that could be reversed by the neutralization of TH. Results The constitutive expression of TH in rBM-MSCs was successfully implemented, without significantly affecting their osteogenic and adipogenic differentiation potential. TH expression improved the expression of other neuronal markers, such as glial fibrillary acidic protein, β-tubulin, nestin, and c-Fos, confirming the neurogenic differentiation capacity of the stem cells. The expression of brain-derived neurotrophic factor (BDNF) and ciliary neurotrophic factor (CNTF) significantly increased after the chemical induction of neurogenic differentiation. Conclusion In this study, the expression of recombinant TH improved the neuroprotective effect of MSCs by upregulating the expression of BDNF and CNTF. Although the neuronal markers were upregulated, the expression of recombinant TH alone in rBM-MSCs was not sufficient for MSCs to differentiate into neurogenic cell lines. PMID:29656620

Targeting Breast Cancer Recurrence via Hedgehog-Mediated Sensitization of Breast Cancer Stem Cells

DTIC Science & Technology

2011-07-01

identification of Notch3 as a transcriptional target of ΔNp63α and a mediator of cellular quiescence in mammary stem cells. 2. Presentation of a poster...enhanced expression of Notch3 in HC11s and breast cancer cell lines, and ectopic expression of the Notch3 intracellular domain (N3ICD) was sufficient to...signaling or shRNA-mediated suppression of Notch3 were sufficient to bypass quiescence induced by ΔNp63α and other quiescence-inducing stimuli. these

Spontaneous endometriosis in a mandrill (Mandrillus sphinx).

PubMed

Nakamura, S; Ochiai, K; Ochi, A; Ito, M; Kamiya, T; Yamamoto, H

2012-01-01

A 25-year-old female mandrill (Mandrillus sphinx) died after exhibiting weakness and recumbency with serosanguineous ascites. Gross findings included haemoperitoneum and multifocal to diffuse serosal thickening with petechiae and ecchymoses throughout the peritoneum. The uterus was covered entirely with large blood clots and was adherent to the ovaries and pelvic wall. Microscopical and immunohistochemical examination revealed extra- and intra-uterine growth of ectopic endometrial tissue with marked fibrosis. The ectopic endometrial tissues predominantly consisted of stromal cells expressing CD10 and progesterone receptor and variably-sized glands lined by the epithelium with occasional slight expression of oestrogen receptor α. A diagnosis of endometriosis was made. This is the first report of naturally occurring endometriosis in a mandrill. Copyright © 2012 Elsevier Ltd. All rights reserved.

MicroRNA-184 inhibits neuroblastoma cell survival through targeting the serine/threonine kinase AKT2

PubMed Central

2010-01-01

Background Neuroblastoma is a paediatric cancer of the sympathetic nervous system. The single most important genetic indicator of poor clinical outcome is amplification of the MYCN transcription factor. One of many down-stream MYCN targets is miR-184, which is either directly or indirectly repressed by this transcription factor, possibly due to its pro-apoptotic effects when ectopically over-expressed in neuroblastoma cells. The purpose of this study was to elucidate the molecular mechanism by which miR-184 conveys pro-apoptotic effects. Results We demonstrate that the knock-down of endogenous miR-184 has the opposite effect of ectopic up-regulation, leading to enhanced neuroblastoma cell numbers. As a mechanism of how miR-184 causes apoptosis when over-expressed, and increased cell numbers when inhibited, we demonstrate direct targeting and degradation of AKT2, a major downstream effector of the phosphatidylinositol 3-kinase (PI3K) pathway, one of the most potent pro-survival pathways in cancer. The pro-apoptotic effects of miR-184 ectopic over-expression in neuroblastoma cell lines is reproduced by siRNA inhibition of AKT2, while a positive effect on cell numbers similar to that obtained by the knock-down of endogenous miR-184 can be achieved by ectopic up-regulation of AKT2. Moreover, co-transfection of miR-184 with an AKT2 expression vector lacking the miR-184 target site in the 3'UTR rescues cells from the pro-apoptotic effects of miR-184. Conclusions MYCN contributes to tumorigenesis, in part, by repressing miR-184, leading to increased levels of AKT2, a direct target of miR-184. Thus, two important genes with positive effects on cell growth and survival, MYCN and AKT2, can be linked into a common genetic pathway through the actions of miR-184. As an inhibitor of AKT2, miR-184 could be of potential benefit in miRNA mediated therapeutics of MYCN amplified neuroblastoma and other forms of cancer. PMID:20409325

Behavior of ectopic surface: effects of beta-adrenergic stimulation and uncoupling.

PubMed

Arutunyan, Ara; Pumir, Alain; Krinsky, Valentin; Swift, Luther; Sarvazyan, Narine

2003-12-01

By using both experimental and theoretical means, we have addressed the progression of ectopic activity from individual cardiac cells to a multicellular two-dimensional network. Experimental conditions that favor ectopic activity have been created by local perfusion of a small area of cardiomyocyte network (I-zone) with an isoproterenol-heptanol containing solution. The application of this solution initially slowed down and then fully blocked wave propagation inside the I-zone. After a brief lag period, ectopically active cells appeared in the I-zone, followed by evolution of the ectopic clusters into slowly propagating waves. The changing pattern of colliding and expanding ectopic waves confined to the I-zone persisted for as long as the isoproterenol-heptanol environment was present. On restoration of the control environment, the ectopic waves from the I-zone broke out into the surrounding network causing arrhythmias. The observed sequence of events was also modeled by FitzHugh-Nagumo equations and included a cell's arrangement of two adjacent square regions of 20 x 20 cells. The control zone consisted of well-connected, excitable cells, and the I-zone was made of weakly coupled cells (heptanol effect), which became spontaneously active as time evolved (isoproterenol effect). The dynamic events in the system have been studied numerically with the use of a finite difference method. Together, our experimental and computational data have revealed that the combination of low coupling, increased excitability, and spatial heterogeneity can lead to the development of ectopic waves confined to the injured network. This transient condition appears to serve as an essential step for the ectopic activity to "mature" before escaping into the surrounding control network.

PRL-3 Is Involved in Estrogen- and IL-6-Induced Migration of Endometrial Stromal Cells From Ectopic Endometrium.

PubMed

Ren, Shifan; Zhou, Yefang; Fang, Xiaoling; She, Xiaoling; Wu, Yilin; Wu, Xianqing

2016-05-24

To investigate the role of phosphatase of regenerating liver-3 (PRL-3) in the 17β-estradiol (E2)- and interleukin 6 (IL-6)-induced migration of endometrial stromal cells (ESCs) from ectopic endometrium. Ectopic endometrial tissues were collected from patients with endometriosis, and PRL-3 expression in ectopic and eutopic endometrium was examined by immunohistochemistry. Endometrial stromal cells isolated from ectopic endometrium were treated with E2, progesterone (P), IL-6, or sodium orthovanadate (Sov) to inhibit PRL-3. Total RNA and protein were extracted from ESCs after treatment for quantitative real-time polymerase chain reaction and Western blot analyses. Cell migration was assessed using a scratch wound assay. Phosphatase of regenerating liver 3 protein was highly expressed in the endometrial glandular cells (EGCs) and ESCs in ectopic endometrium, whereas its weak expression was observed only in EGCs in eutopic endometrium. Both E2 and IL-6 treatment significantly increased PRL-3 messenger RNA and protein expression, and P treatment significantly inhibited PRL-3 expression. However, E2-induced PRL-3 expression in ESCs from ectopic endometrium was significantly blocked by IL-6 antibody. Moreover, E2- and IL-6-enhanced cell migration was completely abrogated by Sov treatment. Furthermore, Sov treatment could significantly promote PTEN expression but inhibit E2- and IL-6-induced p-AKT activation. Phosphatase of regenerating liver 3 plays a key role in the E2- and IL-6-induced migration of ESCs from ectopic endometrium, a process that is involved in the PTEN-AKT signaling pathway. © The Author(s) 2016.

The Pacific White Shrimp β-actin Promoter: Functional Properties and the Potential Application for Transduction System Using Recombinant Baculovirus.

PubMed

Shi, Yingli; Xiang, Jianhai; Zhou, Guangzhou; Ron, Tetsuzan Benny; Tong, Hsin-I; Kang, Wen; Sun, Si; Lu, Yuanan

2016-06-01

A newly isolated Pacific white shrimp (Litopenaeus vannamei) beta-actin promoter SbaP and its derivative compact construct SbaP (ENX) have recently been demonstrated to promote ectopic gene expression in vitro and in vivo. To further explore the potential transduction application, this newly isolated shrimp promoter SbaP was comparatively tested with cytomegalovirus (CMV), simian virus 40 (SV40), polyhedrin (Polh), and white spot syndrome virus immediate early gene 1 (WSSV ie1) four constitutive promoters and a beta-actin promoter (TbaP) from tilapia fish to characterize its promoting function in eight different cell lines. Luciferase quantitation assays revealed that SbaP can drive luciferase gene expression in all eight cell lines including sf21 (insect), PAC2 (zebrafish), EPC (carp), CHSE-214 (chinook salmon), GSTEF (green sea turtle), MS-1 (monk seal), 293T (human), and HeLa (human), but at different levels. Comparative analysis revealed that the promoting activity of SbaP was lower (≤10-fold) than CMV but higher (2-20 folds) than Polh in most of these cell lines tested. Whereas, SbaP mediated luciferase expression in sf21 cells was over 20-fold higher than CMV, SV40, Polh, and TbaP promoter. Compared to the SbaP, SbaP (ENX), which was constructed on the basis of SbaP by deletion of two "negative" regulatory elements, exhibited no significant change of promoting activity in EPC and PAC2 cells, but a 5 and 16 % lower promoting effect in 293T and HeLa cells, respectively. Additionally, a recombinant baculovirus was constructed under the control of SbaP (ENX), and efficient promoter activity of newly generated baculoviral vector was detected both in vitro of infected sf21 cells and in vivo of injected indicator shrimp. These results warrant the potential application of SbaP, particularly SbaP (ENX) in ectopic gene expression in future.

Transient ectopic expression of the histone demethylase JMJD3 accelerates the differentiation of human pluripotent stem cells

PubMed Central

Wakabayashi, Shunichi; Soma, Atsumi; Sato, Saeko; Nakatake, Yuhki; Oda, Mayumi; Murakami, Miyako; Sakota, Miki; Chikazawa-Nohtomi, Nana

2016-01-01

Harnessing epigenetic regulation is crucial for the efficient and proper differentiation of pluripotent stem cells (PSCs) into desired cell types. Histone H3 lysine 27 trimethylation (H3K27me3) functions as a barrier against cell differentiation through the suppression of developmental gene expression in PSCs. Here, we have generated human PSC (hPSC) lines in which genome-wide reduction of H3K27me3 can be induced by ectopic expression of the catalytic domain of the histone demethylase JMJD3 (called JMJD3c). We found that transient, forced demethylation of H3K27me3 alone triggers the upregulation of mesoendodermal genes, even when the culture conditions for the hPSCs are not changed. Furthermore, transient and forced expression of JMJD3c followed by the forced expression of lineage-defining transcription factors enabled the hPSCs to activate tissue-specific genes directly. We have also shown that the introduction of JMJD3c facilitates the differentiation of hPSCs into functional hepatic cells and skeletal muscle cells. These results suggest the utility of the direct manipulation of epigenomes for generating desired cell types from hPSCs for cell transplantation therapy and platforms for drug screenings. PMID:27802135

The ectopic expression of Pax4 in the mouse pancreas converts progenitor cells into alpha and subsequently beta cells.

PubMed

Collombat, Patrick; Xu, Xiaobo; Ravassard, Philippe; Sosa-Pineda, Beatriz; Dussaud, Sébastien; Billestrup, Nils; Madsen, Ole D; Serup, Palle; Heimberg, Harry; Mansouri, Ahmed

2009-08-07

We have previously reported that the loss of Arx and/or Pax4 gene activity leads to a shift in the fate of the different endocrine cell subtypes in the mouse pancreas, without affecting the total endocrine cell numbers. Here, we conditionally and ectopically express Pax4 using different cell-specific promoters and demonstrate that Pax4 forces endocrine precursor cells, as well as mature alpha cells, to adopt a beta cell destiny. This results in a glucagon deficiency that provokes a compensatory and continuous glucagon+ cell neogenesis requiring the re-expression of the proendocrine gene Ngn3. However, the newly formed alpha cells fail to correct the hypoglucagonemia since they subsequently acquire a beta cell phenotype upon Pax4 ectopic expression. Notably, this cycle of neogenesis and redifferentiation caused by ectopic expression of Pax4 in alpha cells is capable of restoring a functional beta cell mass and curing diabetes in animals that have been chemically depleted of beta cells.

Behavior of ectopic surface: effects of β-adrenergic stimulation and uncoupling

PubMed Central

Arutunyan, Ara; Pumir, Alain; Krinsky, Valentin; Swift, Luther; Sarvazyan, Narine

2011-01-01

By using both experimental and theoretical means, we have addressed the progression of ectopic activity from individual cardiac cells to a multicellular two-dimensional network. Experimental conditions that favor ectopic activity have been created by local perfusion of a small area of cardiomyocyte network (I-zone) with an isoproterenol-heptanol containing solution. The application of this solution initially slowed down and then fully blocked wave propagation inside the I-zone. After a brief lag period, ectopically active cells appeared in the I-zone, followed by evolution of the ectopic clusters into slowly propagating waves. The changing pattern of colliding and expanding ectopic waves confined to the I-zone persisted for as long as the isoproterenol-heptanol environment was present. On restoration of the control environment, the ectopic waves from the I-zone broke out into the surrounding network causing arrhythmias. The observed sequence of events was also modeled by FitzHugh-Nagumo equations and included a cell’s arrangement of two adjacent square regions of 20 × 20 cells. The control zone consisted of well-connected, excitable cells, and the I-zone was made of weakly coupled cells (heptanol effect), which became spontaneously active as time evolved (isoproterenol effect). The dynamic events in the system have been studied numerically with the use of a finite difference method. Together, our experimental and computational data have revealed that the combination of low coupling, increased excitability, and spatial heterogeneity can lead to the development of ectopic waves confined to the injured network. This transient condition appears to serve as an essential step for the ectopic activity to “mature” before escaping into the surrounding control network. PMID:12893638

Specification of spatial identities of cerebellar neuron progenitors by ptf1a and atoh1 for proper production of GABAergic and glutamatergic neurons.

PubMed

Yamada, Mayumi; Seto, Yusuke; Taya, Shinichiro; Owa, Tomoo; Inoue, Yukiko U; Inoue, Takayoshi; Kawaguchi, Yoshiya; Nabeshima, Yo-Ichi; Hoshino, Mikio

2014-04-02

In the cerebellum, the bHLH transcription factors Ptf1a and Atoh1 are expressed in distinct neuroepithelial regions, the ventricular zone (VZ) and the rhombic lip (RL), and are required for producing GABAergic and glutamatergic neurons, respectively. However, it is unclear whether Ptf1a or Atoh1 is sufficient for specifying GABAergic or glutamatergic neuronal fates. To test this, we generated two novel knock-in mouse lines, Ptf1a(Atoh1) and Atoh1(Ptf1a), that are designed to express Atoh1 and Ptf1a ectopically in the VZ and RL, respectively. In Ptf1a(Atoh1) embryos, ectopically Atoh1-expressing VZ cells produced glutamatergic neurons, including granule cells and deep cerebellar nuclei neurons. Correspondingly, in Atoh1(Ptf1a) animals, ectopically Ptf1a-expressing RL cells produced GABAergic populations, such as Purkinje cells and GABAergic interneurons. Consistent results were also obtained from in utero electroporation of Ptf1a or Atoh1 into embryonic cerebella, suggesting that Ptf1a and Atoh1 are essential and sufficient for GABAergic versus glutamatergic specification in the neuroepithelium. Furthermore, birthdating analyses with BrdU in the knock-in mice or with electroporation studies showed that ectopically produced fate-changed neuronal types were generated at temporal schedules closely simulating those of the wild-type RL and VZ, suggesting that the VZ and RL share common temporal information. Observations of knock-in brains as well as electroporated brains revealed that Ptf1a and Atoh1 mutually negatively regulate their expression, probably contributing to formation of non-overlapping neuroepithelial domains. These findings suggest that Ptf1a and Atoh1 specify spatial identities of cerebellar neuron progenitors in the neuroepithelium, leading to appropriate production of GABAergic and glutamatergic neurons, respectively.

The Gem GTP-binding protein promotes morphological differentiation in neuroblastoma.

PubMed

Leone, A; Mitsiades, N; Ward, Y; Spinelli, B; Poulaki, V; Tsokos, M; Kelly, K

2001-05-31

Gem is a small GTP-binding protein within the Ras superfamily whose function has not been determined. We report here that ectopic Gem expression is sufficient to stimulate cell flattening and neurite extension in N1E-115 and SH-SY5Y neuroblastoma cells, suggesting a role for Gem in cytoskeletal rearrangement and/or morphological differentiation of neurons. Consistent with this potential function, in clinical samples of neuroblastoma, Gem protein was most highly expressed within cells which had differentiated to express ganglionic morphology. Gem was also observed in developing trigeminal nerve ganglia in 12.5 day mouse embryos, demonstrating that Gem expression is a property of normal ganglionic development. Although Gem expression is rare in epithelial and hematopoietic cancer cell lines, constitutive Gem levels were detected in several neuroblastoma cell lines and could be further induced as much as 10-fold following treatment with PMA or the acetylcholine muscarinic agonist, carbachol.

Tethered Hsp90 Inhibitors Carrying Optical or Radioiodinated Probes Reveal Selective Internalization of Ectopic Hsp90 in Malignant Breast Tumor Cells

PubMed Central

Barrott, Jared J.; Hughes, Philip F.; Osada, Takuya; Yang, Xiao-Yi; Hartman, Zachary C.; Loiselle, David R.; Spector, Neil L.; Neckers, Len; Rajaram, Narasimhan; Hu, Fangyao; Ramanujam, Nimmi; Vaidyanathan, Ganesan; Zalutsky, Michael R.; Lyerly, H. Kim; Haystead, Timothy A.

2013-01-01

Summary Hsp90 inhibitors have demonstrated unusual selectivity for tumor cells despite its ubiquitous expression. This phenomenon has remained unexplained but could be influenced by ectopically expressed Hsp90 in tumors. We have synthesized novel Hsp90 inhibitors that can carry optical or radioiodinated probes via a PEG tether. We show that these tethered inhibitors selectively recognize cells expressing ectopic Hsp90 and become internalized. The internalization process is blocked by Hsp90 antibodies, suggesting that active cycling of the protein is occurring at the plasma membrane. In mice, we show exquisite accumulation of the fluor-tethered versions within breast tumors at very sensitive levels. Cell-based assays with the radiolabeled version showed picomolar detection in cells that express ectopic Hsp90. Our findings show that fluor-tethered or radiolabeled inhibitors targeting ectopic Hsp90 can be used to detect breast cancer malignancies through non-invasive imaging. PMID:24035283

miR-218 inhibits the invasive ability of glioma cells by direct downregulation of IKK-{beta}

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

Song, Libing, E-mail: lb.song1@gmail.com; Huang, Quan; Chen, Kun

2010-11-05

Research highlights: {yields} miR-218 is markedly downregulated in glioma cell lines and in primary glioma tissues. {yields} Upregulation of miR-218 dramatically reduces the invasive ability of glioma cells. {yields} Ectopic expression of miR-218 inactivates IKK-{beta}/NF-{kappa}B signaling pathway. {yields} miR-218 directly targets the 3'-untranslated region (3'-UTR) of IKK-{beta}. -- Abstract: Aberrant activation of nuclear factor-kappa B (NF-{kappa}B) pathway has been proven to play important roles in the development and progression of cancers. Activation of NF-{kappa}B via the classical pathway is modulated by I{kappa}Bs kinase (IKK-{beta}). However, the mechanism underlying the epigenetic regulation of IKK-{beta}/NF-{kappa}B pathway remains largely unknown. In this study,more » we found that the expression level of miR-218 was markedly downregulated in glioma cell lines and in human primary glioma tissues. Upregulation of miR-218 dramatically reduced the migratory speed and invasive ability of glioma cells. Furthermore, we showed that ectopically expressing miR-218 in glioma cells resulted in downregulation of matrix metalloproteinase-9 (MMP-9) and reduction in NF-{kappa}B transactivity at a transcriptional level, but inhibition of miR-218 enhanced the expression of MMP-9 and transcriptional activity of NF-{kappa}B. Moreover, we showed that miR-218 inactivated the NF-{kappa}B pathway through downregulating IKK-{beta} expression by directly targeting the 3'-untranslated region (3'-UTR) of IKK-{beta}. Taken together, our results suggest that miR-218 plays an important role in preventing the invasiveness of glioma cells, and our results present a novel mechanism of miRNA-mediated direct suppression of IKK-{beta}/NF-{kappa}B pathway in gliomas.« less

Human Keratinocytes That Express hTERT and Also Bypass a p16INK4a-Enforced Mechanism That Limits Life Span Become Immortal yet Retain Normal Growth and Differentiation Characteristics

PubMed Central

Dickson, Mark A.; Hahn, William C.; Ino, Yasushi; Ronfard, Vincent; Wu, Jenny Y.; Weinberg, Robert A.; Louis, David N.; Li, Frederick P.; Rheinwald, James G.

2000-01-01

Normal human cells exhibit a limited replicative life span in culture, eventually arresting growth by a process termed senescence. Progressive telomere shortening appears to trigger senescence in normal human fibroblasts and retinal pigment epithelial cells, as ectopic expression of the telomerase catalytic subunit, hTERT, immortalizes these cell types directly. Telomerase expression alone is insufficient to enable certain other cell types to evade senescence, however. Such cells, including keratinocytes and mammary epithelial cells, appear to require loss of the pRB/p16INK4a cell cycle control mechanism in addition to hTERT expression to achieve immortality. To investigate the relationships among telomerase activity, cell cycle control, senescence, and differentiation, we expressed hTERT in two epithelial cell types, keratinocytes and mesothelial cells, and determined the effect on proliferation potential and on the function of cell-type-specific growth control and differentiation systems. Ectopic hTERT expression immortalized normal mesothelial cells and a premalignant, p16INK4a-negative keratinocyte line. In contrast, when four keratinocyte strains cultured from normal tissue were transduced to express hTERT, they were incompletely rescued from senescence. After reaching the population doubling limit of their parent cell strains, hTERT+ keratinocytes entered a slow growth phase of indefinite length, from which rare, rapidly dividing immortal cells emerged. These immortal cell lines frequently had sustained deletions of the CDK2NA/INK4A locus or otherwise were deficient in p16INK4a expression. They nevertheless typically retained other keratinocyte growth controls and differentiated normally in culture and in xenografts. Thus, keratinocyte replicative potential is limited by a p16INK4a-dependent mechanism, the activation of which can occur independent of telomere length. Abrogation of this mechanism together with telomerase expression immortalizes keratinocytes without affecting other major growth control or differentiation systems. PMID:10648628

Ectopic expression of protein kinase C-β sensitizes head and neck squamous cell carcinoma to diterpene esters.

PubMed

Adams, Ryan A; D'Souza, Marjorie M A; Pierce, Carly J; Korica, Natasa; Wallwork, Ben; Parsons, Peter G; Panizza, Benedict; Boyle, Glen M

2015-03-01

The objective of this study was to examine the effect of specific Protein kinase C (PKC) isoform re-expression in solid malignancies, particularly head and neck squamous cell carcinoma cell lines, and the impact this may have on treatment with known activators of PKC. The constitutive expression of PKC isoforms were determined in six head and neck squamous cell carcinoma (SCC) cell lines. Cytotoxicity of the prototypic phorbol ester, 12-O-tetradecanoylphorbol-13-acetate (TPA) and the novel diterpene ester PEP005 was established. Viral transduction to re-express PKCβ isoforms in two of these cell lines was performed, and its effect on the sensitivity to the compounds was quantified. Tongue and hypopharyngeal SCC cell lines were resistant to both TPA and PEP005, with the concentration required to inhibit growth by 50% (IC50) being >1,000 ng/ml. CAL-27 (tongue SCC) and FaDu (hypopharyngeal SCC) cell lines re-expressing PKCβI and -βII isoforms demonstrated IC50 of 1-5 ng/ml with TPA or PEP005. Re-expression of PKCβ in head and neck SCC cell lines leads to cells one thousand-times more sensitive to the cytotoxic effects of phorbol or diterpene esters in culture. This highlights the importance of the isoform in tumor progression and presents the potential benefit of these compounds in malignancies expressing the protein, and in combination therapy. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Overexpression of phosphoserine aminotransferase PSAT1 stimulates cell growth and increases chemoresistance of colon cancer cells

PubMed Central

Vié, Nadia; Copois, Virginie; Bascoul-Mollevi, Caroline; Denis, Vincent; Bec, Nicole; Robert, Bruno; Fraslon, Caroline; Conseiller, Emmanuel; Molina, Franck; Larroque, Christian; Martineau, Pierre; Del Rio, Maguy; Gongora, Céline

2008-01-01

Background Colorectal cancer (CRC) is one of the most common causes of cancer death throughout the world. In this work our aim was to study the role of the phosphoserine aminotransferase PSAT1 in colorectal cancer development. Results We first observed that PSAT1 is overexpressed in colon tumors. In addition, we showed that after drug treatment, PSAT1 expression level in hepatic metastases increased in non responder and decreased in responder patients. In experiments using human cell lines, we showed that ectopic PSAT1 overexpression in colon carcinoma SW480 cell line resulted in an increase in its growth rate and survival. In addition, SW480-PSAT1 cells presented a higher tumorigenic potential than SW480 control cells in xenografted mice. Moreover, the SW480-PSAT1 cell line was more resistant to oxaliplatin treatment than the non-transfected SW480 cell line. This resistance resulted from a decrease in the apoptotic response and in the mitotic catastrophes induced by the drug treatment. Conclusion These results show that an enzyme playing a role in the L-serine biosynthesis could be implicated in colon cancer progression and chemoresistance and indicate that PSAT1 represents a new interesting target for CRC therapy. PMID:18221502

Failure in activation of the canonical NF-κB pathway by human T-cell leukemia virus type 1 Tax in non-hematopoietic cell lines

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

Mizukoshi, Terumi; Komori, Hideyuki; Mizuguchi, Mariko

2013-09-01

Human T-cell leukemia virus type 1 (HTLV-1) Tax (Tax1) plays crucial roles in leukemogenesis in part through activation of NF-κB. In this study, we demonstrated that Tax1 activated an NF-κB binding (gpκB) site of the gp34/OX40 ligand gene in a cell type-dependent manner. Our examination showed that the gpκΒ site and authentic NF-κB (IgκB) site were activated by Tax1 in hematopoietic cell lines. Non-hematopoietic cell lines including hepatoma and fibroblast cell lines were not permissive to Tax1-mediated activation of the gpκB site, while the IgκB site was activated in those cells in association with binding of RelB. However RelA bindingmore » was not observed in the gpκB and IgκB sites. Our results suggest that HTLV-1 Tax1 fails to activate the canonical pathway of NF-κB in non-hematopoietic cell lines. Cell type-dependent activation of NF-κB by Tax1 could be associated with pathogenesis by HTLV-1 infection. - Highlights: • HTLV-1 Tax1 does not activate RelA of NF-κB in non-hematopoietic cell lines. • Tax1 activates the NF-κB non-canonical pathway in non-hematopoietic cell lines. • Tax1 does not induce RelA nuclear translocation in those cell lines, unlike TNFα. • The OX40L promoter κB site is activated by ectopic, but not endogenous, RelA.« less

Peroxisome proliferator-activated receptor-β/δ inhibits human neuroblastoma cell tumorigenesis by inducing p53- and SOX2-mediated cell differentiation.

PubMed

Yao, Pei-Li; Chen, Liping; Dobrzański, Tomasz P; Zhu, Bokai; Kang, Boo-Hyon; Müller, Rolf; Gonzalez, Frank J; Peters, Jeffrey M

2017-05-01

Neuroblastoma is a common childhood cancer typically treated by inducing differentiation with retinoic acid (RA). Peroxisome proliferator-activated receptor-β/δ, (PPARβ/δ) is known to promote terminal differentiation of many cell types. In the present study, PPARβ/δ was over-expressed in three human neuroblastoma cell lines, NGP, SK-N-BE(2), and IMR-32, that exhibit high, medium, and low sensitivity, respectively, to retinoic acid-induced differentiation to determine if PPARβ/δ and retinoic acid receptors (RARs) could be jointly targeted to increase the efficacy of treatment. All-trans-RA (atRA) decreased expression of SRY (sex determining region Y)-box 2 (SOX2), a stem cell regulator and marker of de-differentiation, in NGP and SK-N-BE(2) cells with inactive or mutant tumor suppressor p53, respectively. However, atRA did not suppress SOX2 expression in IMR-32 cells carrying wild-type p53. Over-expression and/or ligand activation of PPARβ/δ reduced the average volume and weight of ectopic tumor xenografts from NGP, SK-N-BE(2), or IMR-32 cells compared to controls. Compared with that found with atRA, PPARβ/δ suppressed SOX2 expression in NGP and SK-N-BE(2) cells and ectopic xenografts, and was also effective in suppressing SOX2 expression in IMR-32 cells that exhibit higher p53 expression compared to the former cell lines. Combined, these observations demonstrate that activating or over-expressing PPARβ/δ induces cell differentiation through p53- and SOX2-dependent signaling pathways in neuroblastoma cells and tumors. This suggests that combinatorial activation of both RARα and PPARβ/δ may be suitable as an alternative therapeutic approach for RA-resistant neuroblastoma patients. Published [2016]. This article is a U.S. Government work and is in the public domain in the USA.

Severe hypertension and hypokalemia as first clinical manifestations in ectopic Cushing's syndrome.

PubMed

Fernández-Rodríguez, Eva; Villar-Taibo, Rocío; Pinal-Osorio, Iria; Cabezas-Agrícola, José Manuel; Anido-Herranz, Urbano; Prieto, Alma; Casanueva, Felipe F; Araujo-Vilar, David

2008-08-01

Ectopic ACTH production occurs in about 10% of all cases of Cushing's syndrome, and about 25% of cases of ACTH-dependent Cushing's syndrome. Diverse tumor types are able to produce ACTH ectopically, including small cell lung carcinoma. Ectopic ACTH secretion by malignant neoplasm has been reported to have earlier and more aggressive metabolic effects. We report a 59-year-old male patient with severe hypertension, metabolic alkalosis and hypokalemia as the first clinical manifestations of an ACTH-secreting small cell lung carcinoma, although the typical phenotypic features of Cushing's syndrome were not present. Ectopic Cushing's syndrome should always be ruled out in patients with severe hypertension and hypokalemia.

Perturbation of auxin homeostasis by overexpression of wild-type IAA15 results in impaired stem cell differentiation and gravitropism in roots.

PubMed

Yan, Da-Wei; Wang, Jing; Yuan, Ting-Ting; Hong, Li-Wei; Gao, Xiang; Lu, Ying-Tang

2013-01-01

Aux/IAAs interact with auxin response factors (ARFs) to repress their transcriptional activity in the auxin signaling pathway. Previous studies have focused on gain-of-function mutations of domain II and little is known about whether the expression level of wild-type Aux/IAAs can modulate auxin homeostasis. Here we examined the perturbation of auxin homeostasis by ectopic expression of wild-type IAA15. Root gravitropism and stem cell differentiation were also analyzed. The transgenic lines were less sensitive to exogenous auxin and exhibited low-auxin phenotypes including failures in gravity response and defects in stem cell differentiation. Overexpression lines also showed an increase in auxin concentration and reduced polar auxin transport. These results demonstrate that an alteration in the expression of wild-type IAA15 can disrupt auxin homeostasis.

Targeting Phosphatidylinositide3-Kinase/Akt pathway by BKM120 for radiosensitization in hepatocellular carcinoma

PubMed Central

Liu, Wei-Lin; Gao, Ming; Tzen, Kai-Yuan; Tsai, Chiao-Ling; Hsu, Feng-Ming; Cheng, Ann-Lii; Cheng, Jason Chia-Hsien

2014-01-01

Tumor control of hepatocellular carcinoma by radiotherapy remains unsatisfactory. The phosphatidylinositol 3-kinase (PI3K)/Akt pathway plays a critical role in inhibiting cancer cell death. Elevated PI3K/Akt activity is associated with increased cellular resistance to irradiation. Our aim was to determine whether the inhibition of PI3K/Akt activity by a PI3K inhibitor, BKM120, contributes to the increased sensitivity of liver cancer cells to irradiation. The hepatocellular carcinoma cell lines (Huh7 and BNL) were used to evaluate the in vitro synergism between BKM120 and irradiation. Balb/c mice bearing ectopic BNL xenografts were treated with BKM120 and/or radiotherapy to assess the in vivo response. BKM120 increased cell killing by radiation, increased the expression of apoptotic markers, and suppressed the repair of radiation-induced DNA double-strand breaks. BKM120 pretreatment inhibited radiation-induced Akt phosphorylation and enhanced the tumor-suppressive effect and radiation-induced tumor cell apoptosis in ectopic xenografts. Inhibition of mTOR phosphorylation by rapamycin enhanced the radiosensitivity of BKM120-treated hepatocellular carcinoma cells. The synergism between BKM120 and irradiation likely inhibits the activation of Akt by radiation, leading to increased cell apoptosis and suppression of DNA-double-strand breaks repair in hepatocellular carcinoma cells. These data suggest that the BKM120/radiation combination may be a strategy worthy of clinical trials. PMID:25004403

Epigenetic identification of ZNF545 as a functional tumor suppressor in multiple myeloma via activation of p53 signaling pathway

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

Fan, Yu; Zhan, Qian; Xu, Hongying

The KRAB–zinc-finger protein ZNF545 was recently identified as a potential suppressor gene in several tumors. However, the regulatory mechanisms of ZNF545 in tumorigenesis remain unclear. In this study, we investigated the expression and roles of ZNF545 in multiple myeloma (MM). ZNF545 was frequently downregulated in MM tissues compared with non-tumor bone marrow tissues. ZNF545 expression was silenced by promoter methylation in MM cell lines, and could be restored by demethylation treatment. ZNF545 methylation was detected in 28.3% of MM tissues, compared with 4.3% of normal bone marrow tissues. ZNF545 transcriptionally activated the p53 signaling pathway but had no effect onmore » Akt in MM, whereas ectopic expression of ZNF545 in silenced cells suppressed their proliferation and induced apoptosis. We therefore identified ZNF545 as a novel tumor suppressor inhibiting tumor growth through activation of the p53 pathway in MM. Moreover, tumor-specific methylation of ZNF545 may represent an epigenetic biomarker for MM diagnosis, and a potential target for specific therapy. -- Highlights: •Downregulated ZNF545 in MM tissues and cell lines and ectopic expression of ZNF545 suppresses tumor growth. •Tumor-specific methylation of ZNF545 represents an epigenetic biomarker for MM diagnosis, and a potential target for specific therapy. •ZNF545 exerts its tumor suppressive effects via transcriptional activating p53 pathway.« less

Up-regulating the abscisic acid inactivation gene ZmABA8ox1b contributes to seed germination heterosis by promoting cell expansion.

PubMed

Li, Yangyang; Wang, Cheng; Liu, Xinye; Song, Jian; Li, Hongjian; Sui, Zhipeng; Zhang, Ming; Fang, Shuang; Chu, Jinfang; Xin, Mingming; Xie, Chaojie; Zhang, Yirong; Sun, Qixin; Ni, Zhongfu

2016-04-01

Heterosis has been widely used in agriculture, but the underlying molecular principles are still largely unknown. During seed germination, we observed that maize (Zea mays) hybrid B73/Mo17 was less sensitive than its parental inbred lines to exogenous abscisic acid (ABA), and endogenous ABA content in hybrid embryos decreased more rapidly than in the parental inbred lines. ZmABA8ox1b, an ABA inactivation gene, was consistently more highly up-regulated in hybrid B73/Mo17 than in its parental inbred lines at early stages of seed germination. Moreover, ectopic expression of ZmABA8ox1b obviously promoted seed germination in Arabidopsis Remarkably, microscopic observation revealed that cell expansion played a major role in the ABA-mediated maize seed germination heterosis, which could be attributed to the altered expression of cell wall-related genes. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

SATB2 expression increased anchorage-independent growth and cell migration in human bronchial epithelial cells

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

Wu, Feng; Jordan, Ashley; Kluz, Thomas

The special AT-rich sequence-binding protein 2 (SATB2) is a protein that binds to the nuclear matrix attachment region of the cell and regulates gene expression by altering chromatin structure. In our previous study, we reported that SATB2 gene expression was induced in human bronchial epithelial BEAS-2B cells transformed by arsenic, chromium, nickel and vanadium. In this study, we show that ectopic expression of SATB2 in the normal human bronchial epithelial cell-line BEAS-2B increased anchorage-independent growth and cell migration, meanwhile, shRNA-mediated knockdown of SATB2 significantly decreased anchorage-independent growth in Ni transformed BEAS-2B cells. RNA sequencing analyses of SATB2 regulated genes revealedmore » the enrichment of those involved in cytoskeleton, cell adhesion and cell-movement pathways. Our evidence supports the hypothesis that SATB2 plays an important role in BEAS-2B cell transformation. - Highlights: • We performed SATB2 overexpression in the BEAS-2B cell line. • We performed SATB2 knockdown in a Ni transformed BEAS-2B cell line. • SATB2 induced anchorage-independent growth and increased cell migration. • SATB2 knockdown significantly decreased anchorage-independent growth. • We identified alterations in gene involved in cytoskeleton, cell adhesion.« less

Ionizing Radiation–Inducible miR-27b Suppresses Leukemia Proliferation via Targeting Cyclin A2

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

Wang, Bo; Li, Dongping; Kovalchuk, Anna

2014-09-01

Purpose: Ionizing radiation is a common carcinogen that is important for the development of leukemia. However, the underlying epigenetic mechanisms remain largely unknown. The goal of the study was to explore microRNAome alterations induced by ionizing radiation (IR) in murine thymus, and to determine the role of IR-inducible microRNA (miRNA/miR) in the development of leukemia. Methods and Materials: We used the well-established C57BL/6 mouse model and miRNA microarray profiling to identify miRNAs that are differentially expressed in murine thymus in response to irradiation. TIB152 human leukemia cell line was used to determine the role of estrogen receptor–α (ERα) in miR-27bmore » transcription. The biological effects of ectopic miR-27b on leukemogenesis were measured by western immunoblotting, cell viability, apoptosis, and cell cycle analyses. Results: Here, we have shown that IR triggers the differential expression of miR-27b in murine thymus tissue in a dose-, time- and sex-dependent manner. miR-27b was significantly down-regulated in leukemia cell lines CCL119 and TIB152. Interestingly, ERα was overexpressed in those 2 cell lines, and it was inversely correlated with miR-27b expression. Therefore, we used TIB152 as a model system to determine the role of ERα in miR-27b expression and the contribution of miR-27b to leukemogenesis. β-Estradiol caused a rapid and transient reduction in miR-27b expression reversed by either ERα-neutralizing antibody or ERK1/2 inhibitor. Ectopic expression of miR-27b remarkably suppressed TIB152 cell proliferation, at least in part, by inducing S-phase arrest. In addition, it attenuated the expression of cyclin A2, although it had no effect on the levels of PCNA, PPARγ, CDK2, p21, p27, p-p53, and cleaved caspase-3. Conclusion: Our data reveal that β-estradiol/ERα signaling may contribute to the down-regulation of miR-27b in acute leukemia cell lines through the ERK1/2 pathway, and that miR-27b may function as a tumor suppressor that inhibits cell proliferation by targeting cyclin A2.« less

Status epilepticus increases mature granule cells in the molecular layer of the dentate gyrus in rats★

PubMed Central

Liang, Zhaoliang; Gao, Fei; Wang, Fajun; Wang, Xiaochen; Song, Xinyu; Liu, Kejing; Zhan, Ren-Zhi

2013-01-01

Enhanced neurogenesis in the dentate gyrus of the hippocampus following seizure activity, especially status epilepticus, is associated with ectopic residence and aberrant integration of newborn granule cells. Hilar ectopic granule cells may be detrimental to the stability of dentate circuitry by means of their electrophysiological properties and synaptic connectivity. We hypothesized that status epilepticus also increases ectopic granule cells in the molecular layer. Status epilepticus was induced in male Sprague-Dawley rats by intraperitoneal injection of pilocarpine. Immunostaining showed that many doublecortin-positive cells were present in the molecular layer and the hilus 7 days after the induction of status epilepticus. At least 10 weeks after status epilepticus, the estimated number of cells positive for both prospero homeobox protein 1 and neuron-specific nuclear protein in the hilus was significantly increased. A similar trend was also found in the molecular layer. These findings indicate that status epilepticus can increase the numbers of mature and ectopic newborn granule cells in the molecular layer. PMID:25206705

Minimally Invasive Management of Ectopic Pancreas.

PubMed

Vitiello, Gerardo A; Cavnar, Michael J; Hajdu, Cristina; Khaykis, Inessa; Newman, Elliot; Melis, Marcovalerio; Pachter, H Leon; Cohen, Steven M

2017-03-01

The management of ectopic pancreas is not well defined. This study aims to determine the prevalence of symptomatic ectopic pancreas and identify those who may benefit from treatment, with a particular focus on robotically assisted surgical management. Our institutional pathology database was queried to identify a cohort of ectopic pancreas specimens. Additional clinical data regarding clinical symptomatology, diagnostic studies, and treatment were obtained through chart review. Nineteen cases of ectopic pancreas were found incidentally during surgery for another condition or found incidentally in a pathologic specimen (65.5%). Eleven patients (37.9%) reported prior symptoms, notably abdominal pain and/or gastrointestinal bleeding. The most common locations for ectopic pancreas were the duodenum and small bowel (31% and 27.6%, respectively). Three out of 29 cases (10.3%) had no symptoms, but had evidence of preneoplastic changes on pathology, while one harbored pancreatic cancer. Over the years, treatment of ectopic pancreas has shifted from open to laparoscopic and more recently to robotic surgery. Our experience is in line with existing evidence supporting surgical treatment of symptomatic or complicated ectopic pancreas. In the current era, minimally invasive and robotic surgery can be used safely and successfully for treatment of ectopic pancreas.

Human somatic cells subjected to genetic induction with six germ line-related factors display meiotic germ cell-like features

PubMed Central

Medrano, Jose V.; Martínez-Arroyo, Ana M.; Míguez, Jose M.; Moreno, Inmaculada; Martínez, Sebastián; Quiñonero, Alicia; Díaz-Gimeno, Patricia; Marqués-Marí, Ana I.; Pellicer, Antonio; Remohí, Jose; Simón, Carlos

2016-01-01

The in vitro derivation of human germ cells has attracted interest in the last years, but their direct conversion from human somatic cells has not yet been reported. Here we tested the ability of human male somatic cells to directly convert into a meiotic germ cell-like phenotype by inducing them with a combination of selected key germ cell developmental factors. We started with a pool of 12 candidates that were reduced to 6, demonstrating that ectopic expression of the germ line-related genes PRDM1, PRDM14, LIN28A, DAZL, VASA and SYCP3 induced direct conversion of somatic cells (hFSK (46, XY), and hMSC (46, XY)) into a germ cell-like phenotype in vitro. Induced germ cell-like cells showed a marked switch in their transcriptomic profile and expressed several post-meiotic germ line related markers, showed meiotic progression, evidence of epigenetic reprogramming, and approximately 1% were able to complete meiosis as demonstrated by their haploid status and the expression of several post-meiotic markers. Furthermore, xenotransplantation assays demonstrated that a subset of induced cells properly colonize the spermatogonial niche. Knowledge obtained from this work can be used to create in vitro models to study gamete-related diseases in humans. PMID:27112843

Reactive oxygen species contribute to arsenic-induced EZH2 phosphorylation in human bronchial epithelial cells and lung cancer cells

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

Li, Lingzhi; Qiu, Ping; Chen, Bailing

Our previous studies suggested that arsenic is able to induce serine 21 phosphorylation of the EZH2 protein through activation of JNK, STAT3, and Akt signaling pathways in the bronchial epithelial cell line, BEAS-2B. In the present report, we further demonstrated that reactive oxygen species (ROS) were involved in the arsenic-induced protein kinase activation that leads to EZH2 phosphorylation. Several lines of evidence supported this notion. First, the pretreatment of the cells with N-acetyl-L-cysteine (NAC), a potent antioxidant, abolishes arsenic-induced EZH2 phosphorylation along with the inhibition of JNK, STAT3, and Akt. Second, H{sub 2}O{sub 2}, the most important form of ROSmore » in the cells in response to extracellular stress signals, can induce phosphorylation of the EZH2 protein and the activation of JNK, STAT3, and Akt. By ectopic expression of the myc-tagged EZH2, we additionally identified direct interaction and phosphorylation of the EZH2 protein by Akt in response to arsenic and H{sub 2}O{sub 2}. Furthermore, both arsenic and H{sub 2}O{sub 2} were able to induce the translocation of ectopically expressed or endogenous EZH2 from nucleus to cytoplasm. In summary, the data presented in this report indicate that oxidative stress due to ROS generation plays an important role in the arsenic-induced EZH2 phosphorylation. - Highlights:: • Arsenic (As{sup 3+}) induces EZH phosphorylation. • JNK, STAT3, and Akt contribute to EZH2 phosphorylation. • Oxidative stress is involved in As{sup 3+}-induced EZH2 phosphorylation. • As{sup 3+} induces direct interaction of Akt and EZH2. • Phosphorylated EZH2 localized in cytoplasm.« less

Screening drug-induced arrhythmia [corrected] using human induced pluripotent stem cell-derived cardiomyocytes and low-impedance microelectrode arrays.

PubMed

Navarrete, Enrique G; Liang, Ping; Lan, Feng; Sanchez-Freire, Verónica; Simmons, Chelsey; Gong, Tingyu; Sharma, Arun; Burridge, Paul W; Patlolla, Bhagat; Lee, Andrew S; Wu, Haodi; Beygui, Ramin E; Wu, Sean M; Robbins, Robert C; Bers, Donald M; Wu, Joseph C

2013-09-10

Drug-induced arrhythmia is one of the most common causes of drug development failure and withdrawal from market. This study tested whether human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) combined with a low-impedance microelectrode array (MEA) system could improve on industry-standard preclinical cardiotoxicity screening methods, identify the effects of well-characterized drugs, and elucidate underlying risk factors for drug-induced arrhythmia. hiPSC-CMs may be advantageous over immortalized cell lines because they possess similar functional characteristics as primary human cardiomyocytes and can be generated in unlimited quantities. Pharmacological responses of beating embryoid bodies exposed to a comprehensive panel of drugs at 65 to 95 days postinduction were determined. Responses of hiPSC-CMs to drugs were qualitatively and quantitatively consistent with the reported drug effects in literature. Torsadogenic hERG blockers, such as sotalol and quinidine, produced statistically and physiologically significant effects, consistent with patch-clamp studies, on human embryonic stem cell-derived cardiomyocytes hESC-CMs. False-negative and false-positive hERG blockers were identified accurately. Consistent with published studies using animal models, early afterdepolarizations and ectopic beats were observed in 33% and 40% of embryoid bodies treated with sotalol and quinidine, respectively, compared with negligible early afterdepolarizations and ectopic beats in untreated controls. We found that drug-induced arrhythmias can be recapitulated in hiPSC-CMs and documented with low impedance MEA. Our data indicate that the MEA/hiPSC-CM assay is a sensitive, robust, and efficient platform for testing drug effectiveness and for arrhythmia screening. This system may hold great potential for reducing drug development costs and may provide significant advantages over current industry standard assays that use immortalized cell lines or animal models.

miR-125b suppresses the proliferation and migration of osteosarcoma cells through down-regulation of STAT3

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

Liu, Li-hong; Li, Hui; Li, Jin-ping

2011-12-09

Highlights: Black-Right-Pointing-Pointer miR-125b is frequently down-regulated in osteosarcoma samples and human osteosarcoma cell lines. Black-Right-Pointing-Pointer Ectopic restoration of miR-125b suppresses cell proliferation and migration in vitro. Black-Right-Pointing-Pointer STAT3 is the direct and functional downstream target of miR-125b. Black-Right-Pointing-Pointer STAT3 can bind to the promoter region of miR-125b and serves as a transactivator. -- Abstract: There is accumulating evidence that microRNAs are involved in multiple processes in development and tumor progression. Abnormally expressed miR-125b was found to play a fundamental role in several types of cancer; however, whether miR-125b participates in regulating the initiation and progress of osteosarcoma still remains unclear.more » Here we demonstrate that miR-125b is frequently down-regulated in osteosarcoma samples and human osteosarcoma cell lines. The ectopic restoration of miR-125b expression in human osteosarcoma cells suppresses proliferation and migration in vitro and inhibits tumor formation in vivo. We further identified signal transducer and activator of transcription 3 (STAT3) as the direct and functional downstream target of miR-125b. Interestingly, we discovered that the expression of miR-125b is regulated by STAT3 at the level of transcription. STAT3 binds to the promoter region of miR-125b in vitro and serves as a transactivator. Taken together, our findings point to an important role in the molecular etiology of osteosarcoma and suggest that miR-125b is a potential target in the treatment of osteosarcoma.« less

Protein S-Nitrosylation Regulates Xylem Vessel Cell Differentiation in Arabidopsis.

PubMed

Kawabe, Harunori; Ohtani, Misato; Kurata, Tetsuya; Sakamoto, Tomoaki; Demura, Taku

2018-01-01

Post-translational modifications of proteins have important roles in the regulation of protein activity. One such modification, S-nitrosylation, involves the covalent binding of nitric oxide (NO)-related species to a cysteine residue. Recent work showed that protein S-nitrosylation has crucial functions in plant development and environmental responses. In the present study, we investigated the importance of protein S-nitrosylation for xylem vessel cell differentiation using a forward genetics approach. We performed ethyl methanesulfonate mutagenesis of a transgenic Arabidopsis 35S::VND7-VP16-GR line in which the activity of VASCULAR-RELATED NAC-DOMAIN7 (VND7), a key transcription factor involved in xylem vessel cell differentiation, can be induced post-translationally by glucocorticoid treatment, with the goal of obtaining suppressor mutants that failed to differentiate ectopic xylem vessel cells; we named these mutants suppressor of ectopic vessel cell differentiation induced by VND7 (seiv) mutants. We found the seiv1 mutant to be a recessive mutant in which ectopic xylem cell differentiation was inhibited, especially in aboveground organs. In seiv1 mutants, a single nucleic acid substitution (G to A) leading to an amino acid substitution (E36K) was present in the gene encoding S-NITROSOGLUTATHIONE REDUCTASE 1 (GSNOR1), which regulates the turnover of the natural NO donor, S-nitrosoglutathione. An in vitro S-nitrosylation assay revealed that VND7 can be S-nitrosylated at Cys264 and Cys320 located near the transactivation activity-related domains, which were shown to be important for transactivation activity of VND7 by transient reporter assay. Our results suggest crucial roles for GSNOR1-regulated protein S-nitrosylation in xylem vessel cell differentiation, partly through the post-translational modification of VND7. © The Author 2017. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Restrictions in Cell Cycle Progression of Adult Vestibular Supporting Cells in Response to Ectopic Cyclin D1 Expression

PubMed Central

Loponen, Heidi; Ylikoski, Jukka; Albrecht, Jeffrey H.; Pirvola, Ulla

2011-01-01

Sensory hair cells and supporting cells of the mammalian inner ear are quiescent cells, which do not regenerate. In contrast, non-mammalian supporting cells have the ability to re-enter the cell cycle and produce replacement hair cells. Earlier studies have demonstrated cyclin D1 expression in the developing mouse supporting cells and its downregulation along maturation. In explant cultures of the mouse utricle, we have here focused on the cell cycle control mechanisms and proliferative potential of adult supporting cells. These cells were forced into the cell cycle through adenoviral-mediated cyclin D1 overexpression. Ectopic cyclin D1 triggered robust cell cycle re-entry of supporting cells, accompanied by changes in p27Kip1 and p21Cip1 expressions. Main part of cell cycle reactivated supporting cells were DNA damaged and arrested at the G2/M boundary. Only small numbers of mitotic supporting cells and rare cells with signs of two successive replications were found. Ectopic cyclin D1-triggered cell cycle reactivation did not lead to hyperplasia of the sensory epithelium. In addition, a part of ectopic cyclin D1 was sequestered in the cytoplasm, reflecting its ineffective nuclear import. Combined, our data reveal intrinsic barriers that limit proliferative capacity of utricular supporting cells. PMID:22073316

Restrictions in cell cycle progression of adult vestibular supporting cells in response to ectopic cyclin D1 expression.

PubMed

Loponen, Heidi; Ylikoski, Jukka; Albrecht, Jeffrey H; Pirvola, Ulla

2011-01-01

Sensory hair cells and supporting cells of the mammalian inner ear are quiescent cells, which do not regenerate. In contrast, non-mammalian supporting cells have the ability to re-enter the cell cycle and produce replacement hair cells. Earlier studies have demonstrated cyclin D1 expression in the developing mouse supporting cells and its downregulation along maturation. In explant cultures of the mouse utricle, we have here focused on the cell cycle control mechanisms and proliferative potential of adult supporting cells. These cells were forced into the cell cycle through adenoviral-mediated cyclin D1 overexpression. Ectopic cyclin D1 triggered robust cell cycle re-entry of supporting cells, accompanied by changes in p27(Kip1) and p21(Cip1) expressions. Main part of cell cycle reactivated supporting cells were DNA damaged and arrested at the G2/M boundary. Only small numbers of mitotic supporting cells and rare cells with signs of two successive replications were found. Ectopic cyclin D1-triggered cell cycle reactivation did not lead to hyperplasia of the sensory epithelium. In addition, a part of ectopic cyclin D1 was sequestered in the cytoplasm, reflecting its ineffective nuclear import. Combined, our data reveal intrinsic barriers that limit proliferative capacity of utricular supporting cells.

microRNA-26a suppresses recruitment of macrophages by down-regulating macrophage colony-stimulating factor expression through the PI3K/Akt pathway in hepatocellular carcinoma.

PubMed

Chai, Zong-Tao; Zhu, Xiao-Dong; Ao, Jian-Yang; Wang, Wen-Quan; Gao, Dong-Mei; Kong, Jian; Zhang, Ning; Zhang, Yuan-Yuan; Ye, Bo-Gen; Ma, De-Ning; Cai, Hao; Sun, Hui-Chuan

2015-05-29

microRNAs (miRNAs) have been reported to modulate macrophage colony-stimulating factor (M-CSF) and macrophages. The aim of this study was to find whether miR-26a can suppress M-CSF expression and the recruitment of macrophages. Hepatocellular carcinoma (HCC) cell lines with decreased or increased expression of miR-26a were established in a previous study. M-CSF expression by tumor cells was measured by enzyme-linked immunosorbent assay, and cell migration assays were used to explore the effect of HCC cell lines on macrophage recruitment in vitro. Real-time PCR measured a panel of mRNAs expressed by macrophages. Xenograft models were used to observe tumor growth. Immunohistochemistry was conducted to study the relation between miR-26a expression and M-CSF expression and macrophage recruitment in patients with HCC. Ectopic expression of miR-26a reduced expression of M-CSF. The conditioned medium (CM) from HepG2 cells that overexpressed miR-26a reduced the migration ability of THP-1 cells stimulated by phorbol myristate acetate (PMA) increased expression of interleukin (IL)-12b or IL-23 mRNA and decreased expression of chemokine (C-C motif) ligand (CCL)22, CCL17, and IL-10 mRNA, in comparison to the medium from the parental HepG2 cells. These effects could be interrupted by the PI3K/Akt pathway inhibitor LY294002. Ectopic expression of miR-26a in HCC cells suppressed tumor growth, M-CSF expression, and infiltration of macrophages in tumors. Similar results were also found when using HCCLM3 cells. Furthermore, the expression of miR-26a was inversely correlated with M-CSF expression and macrophage infiltration in tumor tissues from patients with HCC. miR-26a expression reduced M-CSF expression and recruitment of macrophages in HCC.

Ectopic Expression of the Wild Grape WRKY Transcription Factor VqWRKY52 in Arabidopsis thaliana Enhances Resistance to the Biotrophic Pathogen Powdery Mildew But Not to the Necrotrophic Pathogen Botrytis cinerea.

PubMed

Wang, Xianhang; Guo, Rongrong; Tu, Mingxing; Wang, Dejun; Guo, Chunlei; Wan, Ran; Li, Zhi; Wang, Xiping

2017-01-01

WRKY transcription factors are known to play important roles in plant responses to biotic stresses. We previously showed that the expression of the WRKY gene, VqWRKY52 , from Chinese wild Vitis quinquangularis was strongly induced 24 h post inoculation with powdery mildew. In this study, we analyzed the expression levels of VqWRKY52 following treatment with the defense related hormones salicylic acid (SA) and methyl jasmonate, revealing that VqWRKY52 was strongly induced by SA but not JA. We characterized the VqWRKY52 gene, which encodes a WRKY III gene family member, and found that ectopic expression in Arabidopsis thaliana enhanced resistance to powdery mildew and Pseudomonas syringae pv. tomato DC3000, but increased susceptibility to Botrytis cinerea , compared with wild type (WT) plants. The transgenic A. thaliana lines displayed strong cell death induced by the biotrophic powdery mildew pathogen, the hemibiotrophic P. syringe pathogen and the necrotrophic pathogen B. cinerea . In addition, the relative expression levels of various defense-related genes were compared between the transgenic A. thaliana lines and WT plants following the infection by different pathogens. Collectively, the results indicated that VqWRKY52 plays essential roles in the SA dependent signal transduction pathway and that it can enhance the hypersensitive response cell death triggered by microbial pathogens.

Mechanism of Telomerase Activation by v-Rel and Its Contribution to Transformation

PubMed Central

Hrdličková, Radmila; Nehyba, Jiří; Liss, Andrew S.; Bose, Henry R.

2006-01-01

Telomerase is activated during the transformation of lymphoid cells and fibroblasts by v-Rel, the oncogenic member of the Rel/NF-κB family of transcription factors. v-Rel-transformed cell lines have longer telomeres than untransformed chicken lymphoid cells and have high levels of telomerase activity. v-Rel-mediated activation of telomerase is achieved by multiple mechanisms. The expression of the gene encoding the catalytic subunit of telomerase (TERT) was directly upregulated by v-Rel. Moreover, the expression of v-Rel altered the ratio of alternatively spliced and full-length TERT transcripts in favor of the full-length forms. The activation of telomerase by v-Rel in lymphocytes was also accompanied by inactivation of nuclear inhibitors. The inhibition of telomerase activity in v-Rel-transformed cell lines led to apoptosis within 24 h. The expression of v-Rel in a macrophage cell line resulted in elevated levels of reactive oxygen species (ROS), increased telomerase activity, and increased sensitivity to telomerase inhibitors. In contrast, the ectopic expression of TERT decreased the extent of apoptosis induced by ROS. The activation of telomerase by v-Rel may, therefore, partially protect the transformed cells from apoptosis induced by ROS. PMID:16352553

miR-22 suppresses the proliferation and invasion of gastric cancer cells by inhibiting CD151

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

Wang, Xun; Yu, Honggang, E-mail: honggang_yuwh@163.com; Lu, Xinyao

2014-02-28

Highlights: • miR-22 was decreased in GC tissue samples and cell lines. • miR-22 suppressed GC cell growth and motility in vitro. • CD151 was a direct target of miR-22. • miR-22 suppressed GC cell growth and motility by inhibiting CD151. - Abstract: Gastric cancer (GC) is the second common cause of cancer-related death worldwide. microRNAs (miRNAs) play important roles in the carcinogenesis of GC. Here, we found that miR-22 was significantly decreased in GC tissue samples and cell lines. Ectopic overexpression of miR-22 remarkably suppressed cell proliferation and colony formation of GC cells. Moreover, overexpression of miR-22 significantly suppressedmore » migration and invasion of GC cells. CD151 was found to be a target of miR-22. Furthermore, overexpression of CD151 significantly attenuated the tumor suppressive effect of miR-22. Taken together, miR-22 might suppress GC cells growth and motility partially by inhibiting CD151.« less

Obatoclax, a Pan-BCL-2 Inhibitor, Targets Cyclin D1 for Degradation to Induce Antiproliferation in Human Colorectal Carcinoma Cells.

PubMed

Or, Chi-Hung R; Chang, Yachu; Lin, Wei-Cheng; Lee, Wee-Chyan; Su, Hong-Lin; Cheung, Muk-Wing; Huang, Chang-Po; Ho, Cheesang; Chang, Chia-Che

2016-12-27

Colorectal cancer is the third most common cancer worldwide. Aberrant overexpression of antiapoptotic BCL-2 (B-cell lymphoma 2) family proteins is closely linked to tumorigenesis and poor prognosis in colorectal cancer. Obatoclax is an inhibitor targeting all antiapoptotic BCL-2 proteins. A previous study has described the antiproliferative action of obatoclax in one human colorectal cancer cell line without elucidating the underlying mechanisms. We herein reported that, in a panel of human colorectal cancer cell lines, obatoclax inhibits cell proliferation, suppresses clonogenicity, and induces G₁-phase cell cycle arrest, along with cyclin D1 downregulation. Notably, ectopic cyclin D1 overexpression abrogated clonogenicity suppression but also G₁-phase arrest elicited by obatoclax. Mechanistically, pre-treatment with the proteasome inhibitor MG-132 restored cyclin D1 levels in all obatoclax-treated cell lines. Cycloheximide chase analyses further revealed an evident reduction in the half-life of cyclin D1 protein by obatoclax, confirming that obatoclax downregulates cyclin D1 through induction of cyclin D1 proteasomal degradation. Lastly, threonine 286 phosphorylation of cyclin D1, which is essential for initiating cyclin D1 proteasomal degradation, was induced by obatoclax in one cell line but not others. Collectively, we reveal a novel anticancer mechanism of obatoclax by validating that obatoclax targets cyclin D1 for proteasomal degradation to downregulate cyclin D1 for inducing antiproliferation.

Interleukin-7-induced Stat-5 acts in synergy with Flt-3 signaling to stimulate expansion of hematopoietic progenitor cells.

PubMed

Åhsberg, Josefine; Tsapogas, Panagiotis; Qian, Hong; Zetterblad, Jenny; Zandi, Sasan; Månsson, Robert; Jönsson, Jan-Ingvar; Sigvardsson, Mikael

2010-11-19

The development of lymphoid cells from bone marrow progenitors is dictated by interplay between internal cues such as transcription factors and external signals like the cytokines Flt-3 ligand and Il-7. These proteins are both of large importance for normal lymphoid development; however, it is unclear if they act in direct synergy to expand a transient Il-7R(+)Flt-3(+) population or if the collaboration is created through sequential activities. We report here that Flt-3L and Il-7 synergistically stimulated the expansion of primary Il-7R(+)Flt-3(+) progenitor cells and a hematopoietic progenitor cell line ectopically expressing the receptors. The stimulation resulted in a reduced expression of pro-apoptotic genes and also mediated survival of primary progenitor cells in vitro. However, functional analysis of single cells suggested that the anti-apoptotic effect was additive indicating that the synergy observed mainly depends on stimulation of proliferation. Analysis of downstream signaling events suggested that although Il-7 induced Stat-5 phosphorylation, Flt-3L caused activation of the ERK and AKT signaling pathways. Flt-3L could also drive proliferation in synergy with ectopically expressed constitutively active Stat-5. This synergy could be inhibited with either receptor tyrosine kinase or MAPK inhibitors suggesting that Flt-3L and Il-7 act in synergy by activation of independent signaling pathways to expand early hematopoietic progenitors.

Ell3 stimulates proliferation, drug resistance, and cancer stem cell properties of breast cancer cells via a MEK/ERK-dependent signaling pathway

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

Ahn, Hee-Jin; Kim, Gwangil; Park, Kyung-Soon, E-mail: kspark@cha.ac.kr

2013-08-09

Highlights: •Ell3 enhances proliferation and drug resistance of breast cancer cell lines. •Ell3 is related to the cancer stem cell characteristics of breast cancer cell lines. •Ell3 enhances oncogenicity of breast cancer through the ERK1/2 signaling pathway. -- Abstract: Ell3 is a RNA polymerase II transcription elongation factor that is enriched in testis. The C-terminal domain of Ell3 shows strong similarities to that of Ell (eleven−nineteen lysine-rich leukemia gene), which acts as a negative regulator of p53 and regulates cell proliferation and survival. Recent studies in our laboratory showed that Ell3 induces the differentiation of mouse embryonic stem cells bymore » protecting differentiating cells from apoptosis via the promotion of p53 degradation. In this study, we evaluated the function of Ell3 in breast cancer cell lines. MCF-7 cell lines overexpressing Ell3 were used to examine cell proliferation and cancer stem cell properties. Ectopic expression of Ell3 in breast cancer cell lines induces proliferation and 5-FU resistance. In addition, Ell3 expression increases the cancer stem cell population, which is characterized by CD44 (+) or ALDH1 (+) cells. Mammosphere-forming potential and migration ability were also increased upon Ell3 expression in breast cancer cell lines. Through biochemical and molecular biological analyses, we showed that Ell3 regulates proliferation, cancer stem cell properties and drug resistance in breast cancer cell lines partly through the MEK−extracellular signal-regulated kinase signaling pathway. Murine xenograft experiments showed that Ell3 expression promotes tumorigenesis in vivo. These results suggest that Ell3 may play a critical role in promoting oncogenesis in breast cancer by regulating cell proliferation and cancer stem cell properties via the ERK1/2 signaling pathway.« less

Discovery of ALK-PTPN3 gene fusion from human non-small cell lung carcinoma cell line using next generation RNA sequencing.

PubMed

Jung, Yeonjoo; Kim, Pora; Jung, Yeonhwa; Keum, Juhee; Kim, Soon-Nam; Choi, Yong Soo; Do, In-Gu; Lee, Jinseon; Choi, So-Jung; Kim, Sujin; Lee, Jong-Eun; Kim, Jhingook; Lee, Sanghyuk; Kim, Jaesang

2012-06-01

An increasing number of chromosomal aberrations is being identified in solid tumors providing novel biomarkers for various types of cancer and new insights into the mechanisms of carcinogenesis. We applied next generation sequencing technique to analyze the transcriptome of the non-small cell lung carcinoma (NSCLC) cell line H2228 and discovered a fusion transcript composed of multiple exons of ALK (anaplastic lymphoma receptor tyrosine kinase) and PTPN3 (protein tyrosine phosphatase, nonreceptor Type 3). Detailed analysis of the genomic structure revealed that a portion of genomic region encompassing Exons 10 and 11 of ALK has been translocated into the intronic region between Exons 2 and 3 of PTPN3. The key net result appears to be the null mutation of one allele of PTPN3, a gene with tumor suppressor activity. Consistently, ectopic expression of PTPN3 in NSCLC cell lines led to inhibition of colony formation. Our study confirms the utility of next generation sequencing as a tool for the discovery of somatic mutations and has led to the identification of a novel mutation in NSCLC that may be of diagnostic, prognostic, and therapeutic importance. Copyright © 2012 Wiley Periodicals, Inc.

Effects of an Antagonistic Analog of Growth Hormone-Releasing Hormone on Endometriosis in a Mouse Model and In Vitro.

PubMed

Köster, Frank; Jin, Li; Shen, Yuanming; Schally, Andrew V; Cai, Ren-Zhi; Block, Norman L; Hornung, Daniela; Marschner, Gabriele; Rody, Achim; Engel, Jörg B; Finas, Dominique

2017-11-01

Endometriosis is a benign gynecologic disorder causing dysmenorrhea, pelvic pain, and subfertility. Receptors for the growth hormone-releasing hormone (GHRH) were found in endometriotic tissues. Antagonists of GHRH have been used to inhibit the growth of endometriotic endometrial stromal cells. In this study, the GHRH receptor splice variant (SV) 1 was detected in human endometrial tissue samples by Western blots and quantitative reverse transcription polymerase chain reaction (qRT-PCR). The highest messenger RNA (mRNA) and protein levels of SV1 were found in eutopic endometrium from patients with endometriosis compared to ectopic endometriotic tissues and endometrium from normal patients. The highest expression for GHRH mRNA was found by qRT-PCR in ectopic endometriosis lesions. In an in vivo mouse model with human endometrial explants from patients with endometriosis, 10 μg MIA-602 per day resulted in significantly smaller human endometrial xenotransplants after 4 weeks compared to mice treated with vehicle. The endometrial tissues expressed SV1 before and after xenotransplantation. The proliferation of endometrial stromal cells as well as the endometriosis cell lines 12-Z and 49-Z was decreased by exposure to 1 μM MIA-602 after 72 hours. The protein levels of epithelial growth factor receptors in 12-Z and 49-Z cell lines were reduced 48 and 72 hours after the administration of 1 μM MIA-602. MIA-602 decreased the activation of the MAP-kinases ERK-1/2. Our study demonstrates the presence of SV1 receptor as a target for treatment with GHRH antagonist in endometriosis. Endometrial tissues respond to MIA-602 with inhibition of proliferation in vitro and in vivo. The use of MIA-602 could be an effective supplement to the treatment strategies in endometriosis.

Expression of GRIM-19 in adenomyosis and its possible role in pathogenesis.

PubMed

Wang, Jing; Deng, Xiaohui; Yang, Yang; Yang, Xingsheng; Kong, Beihua; Chao, Lan

2016-04-01

To study the expression of the gene associated with retinoid-interferon (IFN)-induced mortality 19 (GRIM-19) in the endometrial tissue of patients with adenomyosis and to describe the possible pathogenic mechanisms of this phenomenon. Experimental study using human samples and cell lines. University-affiliated hospital. Ectopic and eutopic endometrial tissues were obtained from 30 patients with adenomyosis, whereas normal endometrial specimens were obtained from 10 control patients without adenomyosis. Patients with rapid pathology report-confirmed adenomyosis were recruited, and eutopic and ectopic endometrial tissue samples were collected from patients who had undergone hysterectomies by either the transabdominal or laparoscopic method at Qilu Hospital. Normal endometrial tissue was collected from a group of control patients without adenomyosis. Immunohistochemistry (IHC) was performed to evaluate the expression of GRIM-19, phospho-signal transducer and activator of transcription 3 (Y705) (Y705) (pSTAT3(Y705)), and vascular endothelial growth factor (VEGF) in endometrial tissue samples. The protein levels of GRIM-19, pSTAT3(Y705), STAT3, and VEGF were detected by Western blot. Apoptosis in endometrial specimens was assayed by TUNEL. Immunohistochemistry with an antibody directed against CD34 was performed to detect new blood vessels in the endometrial tissue. GRIM-19 small interfering RNA and a recombinant plasmid carrying GRIM-19 were constructed to evaluate the effects of GRIM-19 on the downstream factors pSTAT3(Y705), STAT3, and VEGF in Ishikawa cells. The expression of GRIM-19 was down-regulated in the eutopic endometria of patients with adenomyosis compared with the endometria of patients in the control group, and it was further reduced in the endometrial glandular epithelial cells of adenomyotic lesions. Apoptosis was reduced in the eutopic endometrium compared with the control group, and it was significantly reduced in ectopic endometrial tissues. In addition, the ectopic and eutopic endometria of patients with adenomyosis displayed a much higher microvessel density. In the eutopic and ectopic endometria of patients with adenomyosis, the expression levels of pSTAT3(Y705) and VEGF were significantly higher than in the controls. Furthermore, down-regulation of GRIM-19 in Ishikawa cells significantly promoted the activation of both pSTAT3(Y705) and its dependent gene VEGF. Aberrant expression of GRIM-19 may be associated with adenomyosis through the regulation of apoptosis and angiogenesis. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Transketolase-like 1 ectopic expression is associated with DNA hypomethylation and induces the Warburg effect in melanoma cells.

PubMed

Jayachandran, Aparna; Lo, Pu-Han; Chueh, Anderly C; Prithviraj, Prashanth; Molania, Ramyar; Davalos-Salas, Mercedes; Anaka, Matthew; Walkiewicz, Marzena; Cebon, Jonathan; Behren, Andreas

2016-02-22

The metabolism of cancer cells is often reprogrammed by dysregulation of metabolic enzymes. Transketolase-like 1 (TKTL1) is a homodimeric transketolase linking the pentose-phosphate pathway with the glycolytic pathway. It is generally silenced at a transcriptional level in somatic tissues. However, in human cancers its expression is associated with the acquisition of a glycolytic phenotype (the Warburg effect) by cancer cells that contributes to the progression of malignant tumors. In melanoma, defective promoter methylation results in the expression of genes and their products that can affect the tumor cell's phenotype including the modification of immune and functional characteristics. The present study evaluates the role of TKTL1 as a mediator of disease progression in melanoma associated with a defective methylation phenotype. The expression of TKTL1 in metastatic melanoma tumors and cell lines was analysed by qRT-PCR and immunohistochemistry. The promoter methylation status of TKTL1 in melanoma cells was evaluated by quantitative methylation specific PCR. Using qRT-PCR, the effect of a DNA demethylating agent 5-aza-2'-deoxycytidine (5aza) on the expression of TKTL1 was examined. Biochemical and molecular analyses such as glucose consumption, lactate production, invasion, proliferation and cell cycle progression together with ectopic expression and siRNA mediated knockdown were used to investigate the role of TKTL1 in melanoma cells. Expression of TKTL1 was highly restricted in normal adult tissues and was overexpressed in a subset of metastatic melanoma tumors and derived cell lines. The TKTL1 promoter was activated by hypomethylation and treatment with 5aza induced TKTL1 expression in melanoma cells. Augmented expression of TKTL1 in melanoma cells was associated with a glycolytic phenotype. Loss and gain of function studies revealed that TKTL1 contributed to enhanced invasion of melanoma cells. Our data provide evidence for an important role of TKTL1 in aerobic glycolysis and tumor promotion in melanoma that may result from defective promoter methylation. This epigenetic change may enable the natural selection of tumor cells with a metabolic phenotype and thereby provide a potential therapeutic target for a subset of melanoma tumors with elevated TKTL1 expression.

Damage-induced ectopic recombination in the yeast Saccharomyces cerevisiae.

PubMed

Kupiec, M; Steinlauf, R

1997-06-09

Mitotic recombination in the yeast Saccharomyces cerevisiae is induced when cells are irradiated with UV or X-rays, reflecting the efficient repair of damage by recombinational repair mechanisms. We have used multiply marked haploid strains that allow the simultaneous detection of several types of ectopic recombination events. We show that inter-chromosomal ectopic conversion of lys2 heteroalleles and, to a lesser extent, direct repeat recombination (DRR) between non-tandem repeats, are increased by DNA-damaging agents; in contrast, ectopic recombination of the naturally occurring Ty element is not induced. We have tested several hypotheses that could explain the preferential lack of induction of Ty recombination by DNA-damaging agents. We have found that the lack of induction cannot be explained by a cell cycle control or by an effect of the mating-type genes. We also found no role for the flanking long terminal repeats (LTRs) of the Ty in preventing the induction. Ectopic conversion, DRR, and forward mutation of artificial repeats show different kinetics of induction at various positions of the cell cycle, reflecting different mechanisms of recombination. We discuss the mechanistic and evolutionary aspects of these results.

Osteophyte formation and matrix mineralization in a TMJ osteoarthritis mouse model are associated with ectopic hedgehog signaling

PubMed Central

Bechtold, Till E.; Saunders, Cheri; Decker, Rebekah S.; Um, Hyo-Bin; Cottingham, Naiga; Salhab, Imad; Kurio, Naito; Billings, Paul C.; Pacifici, Maurizio; Nah, Hyun-Duck; Koyama, Eiki

2016-01-01

The temporomandibular joint (TMJ) is a diarthrodial joint that relies on lubricants for frictionless movement and long-term function. It remains unclear what temporal and causal relationships may exist between compromised lubrication and onset and progression of TMJ disease. Here we report that Proteoglycan 4 (Prg4)-null TMJs exhibit irreversible osteoarthritis-like changes over time and are linked to formation of ectopic mineralized tissues and osteophytes in articular disc, mandibular condyle and glenoid fossa. In the presumptive layer of mutant glenoid fossa’s articulating surface, numerous chondrogenic cells and/or chondrocytes emerged ectopically within the type I collagen-expressing cell population, underwent endochondral bone formation accompanied by enhanced Ihh expression, became entrapped into temporal bone mineralized matrix, and thereby elicited excessive chondroid bone formation. As the osteophytes grew, the roof of the glenoid fossa/eminence became significantly thicker and flatter, resulting in loss of its characteristic concave shape for accommodation of condyle and disc. Concurrently, the condyles became flatter and larger and exhibited ectopic bone along their neck, likely supporting the enlarged condylar heads. Articular discs lost their concave configuration, and ectopic cartilage developed and articulated with osteophytes. In glenoid fossa cells in culture, hedgehog signaling stimulated chondrocyte maturation and mineralization including alkaline phosphatase, while treatment with hedgehog inhibitor HhAntag prevented such maturation process. In sum, our data indicate that Prg4 is needed for TMJ integrity and long-term postnatal function. In its absence, progenitor cells near presumptive articular layer and disc undergo ectopic chondrogenesis and generate ectopic cartilage, possibly driven by aberrant activation of Hh signaling. The data suggest also that the Prg4-null mice represent a useful model to study TMJ osteoarthritis-like degeneration and clarify its pathogenesis. PMID:26945615

miR-17 inhibitor suppressed osteosarcoma tumor growth and metastasis via increasing PTEN expression

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

Gao, Yong, E-mail: gaoyongunion@163.com; Luo, Ling-hui; Li, Shuai

2014-02-07

Highlights: • miR-17 was increased in OS tissues and cell lines. • Inhibition of miR-17 suppressed OS cell proliferation. • Inhibition of miR-17 suppressed OS cell migration and invasion. • PTEN was a target of miR-17. • miR-17 was negatively correlated with PTEN in OS tissues. - Abstract: MicroRNAs (miRNAs) play essential roles in cancer development and progression. Here, we investigated the role of miR-17 in the progression and metastasis of osteosarcoma (OS). miR-17 was frequently increased in OS tissues and cell lines. Inhibition of miR-17 in OS cell lines substantially suppressed cell proliferation, migration, and invasion. Phosphatase and tensinmore » homolog (PTEN) was identified as a target of miR-17, and ectopic expression of miR-17 inhibited PTEN by direct binding to its 3′-untranslated region (3′-UTR). Expression of miR-17 was negatively correlated with PTEN in OS tissues. Together, these findings indicate that miR-17 acts as an oncogenic miRNA and may contribute to the progression and metastasis of OS, suggesting miR-17 as a potential novel diagnostic and therapeutic target of OS.« less

Junction region of EWS-FLI1 fusion protein has a dominant negative effect in Ewing's sarcoma in vitro.

PubMed

Jully, Babu; Vijayalakshmi, Ramshankar; Gopal, Gopisetty; Sabitha, Kesavan; Rajkumar, Thangarajan

2012-11-12

Ewing's sarcoma is a malignancy characterized by a specific 11:22 chromosomal translocation which generates a novel EWS-FLI1 fusion protein functioning as an aberrant transcription factor. In the present study, we have further characterized the junction region of the EWS-FLI1 fusion protein. In-silico model of EWS-FLI1 fusion protein was analysed for ligand binding sites, and a putative region (amino acid (aa) 251-343 of the type 1 fusion protein) in the vicinity of the fusion junction was cloned and expressed using bacterial expression. The recombinant protein was characterized by Circular Dichroism (CD). We then expressed aa 251-280 ectopically in Ewing's sarcoma cell-line and its effect on cell proliferation, tumorigenicity and expression of EWS-FLI1 target genes were analysed. Our modelling analysis indicated that Junction region (aa 251-343) encompasses potential ligand biding sites in the EWS-FLI1 protein and when expressed in bacteria was present as soluble form. Ectopically expressing this region in Ewing's sarcoma cells inhibited tumorigenicity, and EWS-FLI1 target genes indicating a dominant negative biological effect. Junction region can be exploited further as target for drug development in future to specifically target EWS-FLI1 in Ewing's Sarcoma.

Mutations in the murine homologue of TUBB5 cause microcephaly by perturbing cell cycle progression and inducing p53-associated apoptosis.

PubMed

Breuss, Martin; Fritz, Tanja; Gstrein, Thomas; Chan, Kelvin; Ushakova, Lyubov; Yu, Nuo; Vonberg, Frederick W; Werner, Barbara; Elling, Ulrich; Keays, David A

2016-04-01

Microtubules play a crucial role in the generation, migration and differentiation of nascent neurons in the developing vertebrate brain. Mutations in the constituents of microtubules, the tubulins, are known to cause an array of neurological disorders, including lissencephaly, polymicrogyria and microcephaly. In this study we explore the genetic and cellular mechanisms that cause TUBB5-associated microcephaly by exploiting two new mouse models: a conditional E401K knock-in, and a conditional knockout animal. These mice present with profound microcephaly due to a loss of upper-layer neurons that correlates with massive apoptosis and upregulation of p53. This phenotype is associated with a delay in cell cycle progression and ectopic DNA elements in progenitors, which is dependent on the dosage of functional Tubb5. Strikingly, we report ectopic Sox2-positive progenitors and defects in spindle orientation in our knock-in mouse line, which are absent in knockout animals. This work sheds light on the functional repertoire of Tubb5, reveals that the E401K mutation acts by a complex mechanism, and demonstrates that the cellular pathology driving TUBB5-associated microcephaly is cell death. © 2016. Published by The Company of Biologists Ltd.

NR4A3 Suppresses Lymphomagenesis through Induction of Proapoptotic Genes.

PubMed

Deutsch, Alexander J A; Rinner, Beate; Pichler, Martin; Prochazka, Katharina; Pansy, Katrin; Bischof, Marco; Fechter, Karoline; Hatzl, Stefan; Feichtinger, Julia; Wenzl, Kerstin; Frisch, Marie-Therese; Stiegelbauer, Verena; Prokesch, Andreas; Krogsdam, Anne; Sill, Heinz; Thallinger, Gerhard G; Greinix, Hildegard T; Wang, Chenguang; Beham-Schmid, Christine; Neumeister, Peter

2017-05-01

Nuclear orphan receptor NR4A1 exerts an essential tumor suppressor function in aggressive lymphomas. In this study, we investigated the hypothesized contribution of the related NR4A family member NR4A3 to lymphomagenesis. In aggressive lymphoma patients, low expression of NR4A3 was associated with poor survival. Ectopic expression or pharmacological activation of NR4A3 in lymphoma cell lines led to a significantly higher proportion of apoptotic cells. In a mouse NSG xenograft model of lymphoma (stably transduced SuDHL4 cells), NR4A3 expression abrogated tumor growth, compared with vector control and uninduced cells that formed massive tumors. Transcript analysis of four different aggressive lymphoma cell lines overexpressing either NR4A3 or NR4A1 revealed that apoptosis was driven similarly by induction of BAK, Puma, BIK, BIM, BID, and Trail. Overall, our results showed that NR4A3 possesses robust tumor suppressor functions of similar impact to NR4A1 in aggressive lymphomas. Cancer Res; 77(9); 2375-86. ©2017 AACR . ©2017 American Association for Cancer Research.

MiR-767 promoted cell proliferation in human melanoma by suppressing CYLD expression.

PubMed

Zhang, Kejin; Guo, Ling

2018-01-30

MicroRNAs (miRNAs) have emerged as critical regulators for cancer development and progression of human melanoma. However, the potential molecular mechanism of miR-767 in human melanoma has not been intensively investigated. In this present study, we confirmed that miR-767 was frequently up-regulated in human melanoma tissues and cell lines. Ectopic expression of miR-767 promoted cell proliferation in human melanoma cell lines A375 and WM35, whereas miR-767-in reversed the function. Bioinformatics analysis revealed that cylindromatosis (CYLD) was hypothesized to be a possible target gene of miR-767, and this was confirmed by luciferase activity assay. Knockdown of CYLD counteracted the proliferation arrest by miR-767-in in melanoma cells A375 and WM35. In conclusion, our study indicated that miR-767 acted as a role of tumor promoter by targeting CYLD in human melanoma, and might serve as a prognostic or therapeutic target for human melanoma. Copyright © 2017 Elsevier B.V. All rights reserved.

CENP-C and CENP-I are key connecting factors for kinetochore and CENP-A assembly

PubMed Central

Shono, Nobuaki; Ohzeki, Jun-ichirou; Otake, Koichiro; Martins, Nuno M. C.; Nagase, Takahiro; Kimura, Hiroshi; Larionov, Vladimir; Earnshaw, William C.; Masumoto, Hiroshi

2015-01-01

ABSTRACT Although it is generally accepted that chromatin containing the histone H3 variant CENP-A is an epigenetic mark maintaining centromere identity, the pathways leading to the formation and maintenance of centromere chromatin remain unclear. We previously generated human artificial chromosomes (HACs) whose centromeres contain a synthetic alpha-satellite (alphoid) DNA array containing the tetracycline operator (alphoidtetO). We also obtained cell lines bearing the alphoidtetO array at ectopic integration sites on chromosomal arms. Here, we have examined the regulation of CENP-A assembly at centromeres as well as de novo assembly on the ectopic arrays by tethering tetracycline repressor (tetR) fusions of substantial centromeric factors and chromatin modifiers. This analysis revealed four classes of factors that influence CENP-A assembly. Interestingly, many kinetochore structural components induced de novo CENP-A assembly at the ectopic site. We showed that these components work by recruiting CENP-C and subsequently recruiting M18BP1. Furthermore, we found that CENP-I can also recruit M18BP1 and, as a consequence, enhances M18BP1 assembly on centromeres in the downstream of CENP-C. Thus, we suggest that CENP-C and CENP-I are key factors connecting kinetochore to CENP-A assembly. PMID:26527398

Cis-acting regulatory sequences promote high-frequency gene conversion between repeated sequences in mammalian cells.

PubMed

Raynard, Steven J; Baker, Mark D

2004-01-01

In mammalian cells, little is known about the nature of recombination-prone regions of the genome. Previously, we reported that the immunoglobulin heavy chain (IgH) mu locus behaved as a hotspot for mitotic, intrachromosomal gene conversion (GC) between repeated mu constant (Cmu) regions in mouse hybridoma cells. To investigate whether elements within the mu gene regulatory region were required for hotspot activity, gene targeting was used to delete a 9.1 kb segment encompassing the mu gene promoter (Pmu), enhancer (Emu) and switch region (Smu) from the locus. In these cell lines, GC between the Cmu repeats was significantly reduced, indicating that this 'recombination-enhancing sequence' (RES) is necessary for GC hotspot activity at the IgH locus. Importantly, the RES fragment stimulated GC when appended to the same Cmu repeats integrated at ectopic genomic sites. We also show that deletion of Emu and flanking matrix attachment regions (MARs) from the RES abolishes GC hotspot activity at the IgH locus. However, no stimulation of ectopic GC was observed with the Emu/MARs fragment alone. Finally, we provide evidence that no correlation exists between the level of transcription and GC promoted by the RES. We suggest a model whereby Emu/MARS enhances mitotic GC at the endogenous IgH mu locus by effecting chromatin modifications in adjacent DNA.

Inhibition of Oncogenic Transcription Factor REL by the Natural Product Derivative Calafianin Monomer 101 Induces Proliferation Arrest and Apoptosis in Human B-Lymphoma Cell Lines.

PubMed

Yeo, Alan T; Chennamadhavuni, Spandan; Whitty, Adrian; Porco, John A; Gilmore, Thomas D

2015-04-23

Increased activity of transcription factor NF-κB has been implicated in many B-cell lymphomas. We investigated effects of synthetic compound calafianin monomer (CM101) on biochemical and biological properties of NF-κB. In human 293 cells, CM101 selectively inhibited DNA binding by overexpressed NF-κB subunits REL (human c-Rel) and p65 as compared to NF-κB p50, and inhibition of REL and p65 DNA binding by CM101 required a conserved cysteine residue. CM101 also inhibited DNA binding by REL in human B-lymphoma cell lines, and the sensitivity of several B-lymphoma cell lines to CM101-induced proliferation arrest and apoptosis correlated with levels of cellular and nuclear REL. CM101 treatment induced both phosphorylation and decreased expression of anti-apoptotic protein Bcl-XL, a REL target gene product, in sensitive B-lymphoma cell lines. Ectopic expression of Bcl-XL protected SUDHL-2 B-lymphoma cells against CM101-induced apoptosis, and overexpression of a transforming mutant of REL decreased the sensitivity of BJAB B-lymphoma cells to CM101-induced apoptosis. Lipopolysaccharide-induced activation of NF-κB signaling upstream components occurred in RAW264.7 macrophages at CM101 concentrations that blocked NF-κB DNA binding. Direct inhibitors of REL may be useful for treating B-cell lymphomas in which REL is active, and may inhibit B-lymphoma cell growth at doses that do not affect some immune-related responses in normal cells.

Ectopic expression of H2AX protein promotes TrkA-induced cell death via modulation of TrkA tyrosine-490 phosphorylation and JNK activity upon DNA damage

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

Jung, Eun Joo; Kim, Deok Ryong, E-mail: drkim@gnu.ac.kr

2011-01-21

Research highlights: {yields} We established TrkA-inducible U2OS cells stably expressing GFP-H2AX proteins. {yields} GFP-H2AX was colocalized with TrkA in the cytoplasm. {yields} {gamma}H2AX production was significantly increased upon activation of TrkA and suppressed by TrkA inhibitor or JNK inhibitor. {yields} Ectopic expression of H2AX promoted TrkA-mediated cell death through the modulation of TrkA tyrosine-490 phosphorylation and JNK activity upon DNA damage. -- Abstract: We previously reported that TrkA overexpression causes accumulation of {gamma}H2AX proteins in the cytoplasm, subsequently leading to massive cell death in U2OS cells. To further investigate how cytoplasmic H2AX is associated with TrkA-induced cell death, we establishedmore » TrkA-inducible cells stably expressing GFP-tagged H2AX. We found that TrkA co-localizes with ectopically expressed GFP-H2AX proteins in the cytoplasm, especially at the juxta-nuclear membranes, which supports our previous results about a functional connection between TrkA and {gamma}H2AX in TrkA-induced cell death. {gamma}H2AX production from GFP-H2AX proteins was significantly increased when TrkA was overexpressed. Moreover, ectopic expression of H2AX activated TrkA-mediated signal pathways via up-regulation of TrkA tyrosine-490 phosphorylation. In addition, suppression of TrkA tyrosine-490 phosphorylation under a certain condition was removed by ectopic expression of H2AX, indicating a functional role of H2AX in the maintenance of TrkA activity. Indeed, TrkA-induced cell death was highly elevated by ectopic H2AX expression, and it was further accelerated by DNA damage via JNK activation. These all results suggest that cytoplasmic H2AX could play an important role in TrkA-mediated cell death by modulating TrkA upon DNA damage.« less

Masitinib Combined with Standard Gemcitabine Chemotherapy: In Vitro and In Vivo Studies in Human Pancreatic Tumour Cell Lines and Ectopic Mouse Model

PubMed Central

Humbert, Martine; Castéran, Nathalie; Letard, Sébastien; Hanssens, Katia; Iovanna, Juan; Finetti, Pascal; Bertucci, François; Bader, Thomas; Mansfield, Colin D.; Moussy, Alain; Hermine, Olivier; Dubreuil, Patrice

2010-01-01

Background Tyrosine kinases are attractive targets for pancreatic cancer therapy because several are over-expressed, including PDGFRα/β, FAK, Src and Lyn. A critical role of mast cells in the development of pancreatic cancer has also been reported. Masitinib is a tyrosine kinase inhibitor that selectively targets c-Kit, PDGFRα/β, Lyn, and to a lesser extent the FAK pathway, without inhibiting kinases of known toxicities. Masitinib is particularly efficient in controlling the proliferation, differentiation and degranulation of mast cells. This study evaluates the therapeutic potential of masitinib in pancreatic cancer, as a single agent and in combination with gemcitabine. Methodology/Findings Proof-of-concept studies were performed in vitro on human pancreatic tumour cell lines and then in vivo using a mouse model of human pancreatic cancer. Molecular mechanisms were investigated via gene expression profiling. Masitinib as a single agent had no significant antiproliferative activity while the masitinib/gemcitabine combination showed synergy in vitro on proliferation of gemcitabine-refractory cell lines Mia Paca2 and Panc1, and to a lesser extent in vivo on Mia Paca2 cell tumour growth. Specifically, masitinib at 10 µM strongly sensitised Mia Paca2 cells to gemcitabine (>400-fold reduction in IC50); and moderately sensitised Panc1 cells (10-fold reduction). Transcriptional analysis identified the Wnt/β-catenin signalling pathway as down-regulated in the cell lines resensitised by the masitinib/gemcitabine combination. Conclusions These data establish proof-of-concept that masitinib can sensitise gemcitabine-refractory pancreatic cancer cell lines and warrant further in vivo investigation. Indeed, such an effect has been recently observed in a phase 2 clinical study of patients with pancreatic cancer who received a masitinib/gemcitabine combination. PMID:20209107

Simulation of Ectopic Pacemakers in the Heart: Multiple Ectopic Beats Generated by Reentry inside Fibrotic Regions

PubMed Central

Gouvêa de Barros, Bruno; Weber dos Santos, Rodrigo; Alonso, Sergio

2015-01-01

The inclusion of nonconducting media, mimicking cardiac fibrosis, in two models of cardiac tissue produces the formation of ectopic beats. The fraction of nonconducting media in comparison with the fraction of healthy myocytes and the topological distribution of cells determines the probability of ectopic beat generation. First, a detailed subcellular microscopic model that accounts for the microstructure of the cardiac tissue is constructed and employed for the numerical simulation of action potential propagation. Next, an equivalent discrete model is implemented, which permits a faster integration of the equations. This discrete model is a simplified version of the microscopic model that maintains the distribution of connections between cells. Both models produce similar results when describing action potential propagation in homogeneous tissue; however, they slightly differ in the generation of ectopic beats in heterogeneous tissue. Nevertheless, both models present the generation of reentry inside fibrotic tissues. This kind of reentry restricted to microfibrosis regions can result in the formation of ectopic pacemakers, that is, regions that will generate a series of ectopic stimulus at a fast pacing rate. In turn, such activity has been related to trigger fibrillation in the atria and in the ventricles in clinical and animal studies. PMID:26583127

CMTM5 exhibits tumor suppressor activity through promoter methylation in oral squamous cell carcinoma

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

Zhang, Heyu; Nan, Xu; Li, Xuefen

Highlights: • Down-regulation of CMTM5 expression in OSCC tissues was found. • The promoter methylation status of CMTM5 was measured. • CMTM5-v1 inhibited cell proliferation and migration and induced apoptosis. • CMTM5 might act as a putative tumor suppressor gene in OSCC. - Abstract: Oral squamous cell carcinoma (OSCC) is one of the most common types of malignancies in the head and neck region. CKLF-like MARVEL transmembrane domain-containing member 5 (CMTM5) has been recently implicated as a tumor suppressor gene in several cancer types. Herein, we examined the expression and function of CMTM5 in oral squamous cell carcinoma. CMTM5 wasmore » down-regulated in oral squamous cell lines and tumor samples from patients with promoter methylation. Treatment with the demethylating agent 5-aza-2′-deoxycytidine restored CMTM5 expression. In the OSCC cell lines CAL27 and GNM, the ectopic expression of CMTM5-v1 strongly inhibited cell proliferation and migration and induced apoptosis. In addition, CMTM5-v1 inhibited tumor formation in vivo. Therefore, CMTM5 might act as a putative tumor suppressor gene through promoter methylation in oral squamous cell carcinoma.« less

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

PubMed

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

2015-07-01

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

Combining Enhanced Root and Shoot Growth Reveals Cross Talk between Pathways That Control Plant Organ Size in Arabidopsis1[C][W][OA

PubMed Central

Vercruyssen, Liesbeth; Gonzalez, Nathalie; Werner, Tomáš; Schmülling, Thomas; Inzé, Dirk

2011-01-01

Functionally distinct Arabidopsis (Arabidopsis thaliana) genes that positively affect root or shoot growth when ectopically expressed were combined to explore the feasibility of enhanced biomass production. Enhanced root growth resulting from cytokinin deficiency was obtained by overexpressing CYTOKININ OXIDASE/DEHYDROGENASE3 (CKX3) under the control of the root-specific PYK10 promoter. Plants harboring the PYK10-CKX3 construct were crossed with four different transgenic lines showing enhanced leaf growth. For all combinations, the phenotypic traits of the individual lines could be combined, resulting in an overall growth increase. Unexpectedly, three out of four combinations had more than additive effects. Both leaf and root growth were synergistically enhanced in plants ectopically expressing CKX3 and BRASSINOSTEROID INSENSITIVE1, indicating cross talk between cytokinins and brassinosteroids. In agreement, treatment of PYK10-CKX3 plants with brassinolide resulted in a dramatic increase in lateral root growth that could not be observed in wild-type plants. Coexpression of CKX3 and the GROWTH-REGULATING FACTOR5 (GRF5) antagonized the effects of GRF5 overexpression, revealing an interplay between cytokinins and GRF5 during leaf cell proliferation. The combined overexpression of CKX3 and GIBBERELLIN 20-OXIDASE1 led to a synergistic increase in leaf growth, suggesting an antagonistic growth control by cytokinins and gibberellins. Only additive effects on root and shoot growth were visible in plants ectopically expressing both CKX3 and ARABIDOPSIS VACUOLAR PYROPHOSPHATASE1, hinting at an independent action mode. Our results show new interactions and contribute to the molecular and physiological understanding of biomass production at the whole plant level. PMID:21205622

Planar cell polarity controls directional Notch signaling in the Drosophila leg

PubMed Central

Capilla, Amalia; Johnson, Ruth; Daniels, Maki; Benavente, María; Bray, Sarah J.; Galindo, Máximo Ibo

2012-01-01

The generation of functional structures during development requires tight spatial regulation of signaling pathways. Thus, in Drosophila legs, in which Notch pathway activity is required to specify joints, only cells distal to ligand-producing cells are capable of responding. Here, we show that the asymmetric distribution of planar cell polarity (PCP) proteins correlates with this spatial restriction of Notch activation. Frizzled and Dishevelled are enriched at distal sides of each cell and hence localize at the interface with ligand-expressing cells in the non-responding cells. Elimination of PCP gene function in cells proximal to ligand-expressing cells is sufficient to alleviate the repression, resulting in ectopic Notch activity and ectopic joint formation. Mutations that compromise a direct interaction between Dishevelled and Notch reduce the efficacy of repression. Likewise, increased Rab5 levels or dominant-negative Deltex can suppress the ectopic joints. Together, these results suggest that PCP coordinates the spatial activity of the Notch pathway by regulating endocytic trafficking of the receptor. PMID:22736244

Glycogen synthase kinase 3 regulates PAX3-FKHR-mediated cell proliferation in human alveolar rhabdomyosarcoma cells

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

Zeng, Fu-Yue; Dong, Hanqing; Cui, Jimmy

2010-01-01

Patients with alveolar rhabdomyosarcoma (ARMS) have poorer response to conventional chemotherapy and lower survival rates than those with embryonal RMS (ERMS). To identify compounds that preferentially block the growth of ARMS, we conducted a small-scale screen of 160 kinase inhibitors against the ARMS cell line Rh30 and ERMS cell line RD and identified inhibitors of glycogen synthase kinase 3 (GSK3), including TWS119 as ARMS-selective inhibitors. GSK3 inhibitors inhibited cell proliferation and induced apoptosis more effectively in Rh30 than RD cells. Ectopic expression of fusion protein PAX3-FKHR in RD cells significantly increased their sensitivity to TWS119. Down-regulation of GSK3 by GSK3more » inhibitors or siRNA significantly reduced the transcriptional activity of PAX3-FKHR. These results suggest that GSK3 is directly involved in regulating the transcriptional activity of PAX3-FKHR. Also, GSK3 phosphorylated PAX3-FKHR in vitro, suggesting that GSK3 might regulate PAX3-FKHR activity via phosphorylation. These findings support a novel mechanism of PAX3-FKHR regulation by GSK3 and provide a novel strategy to develop GSK inhibitors as anti-ARMS therapies.« less

microRNA-497 overexpression decreases proliferation, migration and invasion of human retinoblastoma cells via targeting vascular endothelial growth factor A

PubMed Central

Li, Jianjun; Zhang, Yinghui; Wang, Xiuchao; Zhao, Ruibo

2017-01-01

The expression level and roles of microRNA-497 (miR-497) have been frequently reported in previous studies on cancer. However, its expression, function and associated molecular mechanisms in retinoblastoma remain unknown. In the present study, miR-497 expression levels in human retinoblastoma tissues, normal retinal tissues and retinoblastoma cell lines were determined using reverse transcription-quantitative polymerase chain reaction. In addition, a Cell Counting Kit-8 assay, cell migration assay, cell invasion assay, western blot analysis and Dual-Luciferase reporter assay were used to explore the expression, functions and molecular mechanisms of miR-497 in human retinoblastoma. It was demonstrated that miR-497 was significantly downregulated in retinoblastoma tissues and cell lines compared with normal retinal tissues. Ectopic expression of miR-497 decreased the proliferation, migration and invasion of retinoblastoma cells. Furthermore, VEGFA was verified as a potential direct target of miR-497 in vitro. Taken together, the results indicate that miR-497 functions as a tumor suppressor in the carcinogenesis and progression of retinoblastoma via targeting VEGFA. miR-497 should be investigated as a potential therapeutic target for the treatment of retinoblastoma. PMID:28588740

Microfollicular adenoma of ectopic thyroid gland masquerading as salivary gland tumor - a diagnostic and therapeutic challenge: a case report.

PubMed

Deshmukh, Sanjay D; Khandeparkar, Siddhi G Sinai; Gulati, Harveen K; Naik, Chetana S

2014-08-07

Ectopic thyroid tissue may appear in any location along the trajectory of the thyroglossal duct from the foramen cecum to the mediastinum. Rarely, there is incomplete descent of the gland where the final resting point may be high resulting in sublingual ectopic thyroid tissue. Ectopic thyroid tissue carries a low risk of malignancy. Most recently reported neoplasms in ectopic thyroid tissue have been papillary carcinoma of thyroid. Individual case reports of clear cell type of follicular adenoma within the ectopic thyroid tissue have been described in the literature. We present a rare case of microfollicular follicular adenoma in an ectopic sublingual thyroid tissue presenting as submental swelling in a euthyroid 24-year-old Dravidian woman. Findings in this case emphasize that when confronted with a submental/sublingual mass lesion, the evaluation of thyroid function tests and ultrasonography of the neck should be included in a pre-operative workup.

Functional neurons and melanocytes induced from immortal lines of postnatal neural crest-like stem cells

PubMed Central

Sviderskaya, Elena V.; Easty, David J.; Lawrence, Mark A.; Sánchez, Daniel P.; Negulyaev, Yuri A.; Patel, Ricken H.; Anand, Praveen; Korchev, Yuri E.; Bennett, Dorothy C.

2009-01-01

Stem cells, that is, cells that can both reproduce themselves and differentiate into functional cell types, attract much interest as potential aids to healing and disease therapy. Embryonic neural crest is pluripotent and generates the peripheral nervous system, melanocytes, and some connective tissues. Neural-crest-related stem cells have been reported previously in postnatal skin: committed melanocytic stem cells in the hair follicle, and pluripotent cell types from the hair follicle and papilla that can produce various sets of lineages. Here we describe novel pluripotent neural crest-like stem cells from neonatal mouse epidermis, with different potencies, isolated as 3 independent immortal lines. Using alternative regulatory factors, they could be converted to large numbers of either Schwann precursor cells, pigmented melanocytes, chondrocytes, or functional sensory neurons showing voltage-gated sodium channels. Some of the neurons displayed abundant active TRPV1 and TRPA1 receptors. Such functional neurons have previously been obtained in culture only with difficulty, by explantation. The system was also used to generate comparative gene expression data for the stem cells, melanocytes, and melanoblasts that sufficiently explain the lack of pigment in melanoblasts and provide a rationale for some genes expressed apparently ectopically in melanomas, such as ephrin receptors.—Sviderskaya, E. V., Easty, D. J., Lawrence, M. A., Sánchez, D. P., Negulyaev, Y. A., Patel, R. H., Anand, P., Korchev, Y. E., Bennett, D. C. Functional neurons and melanocytes induced from immortal lines of postnatal neural crest-like stem cells. PMID:19447881

The Tea4-PP1 landmark promotes local growth by dual Cdc42 GEF recruitment and GAP exclusion.

PubMed

Kokkoris, Kyriakos; Gallo Castro, Daniela; Martin, Sophie G

2014-05-01

Cell polarization relies on small GTPases, such as Cdc42, which can break symmetry through self-organizing principles, and landmarks that define the axis of polarity. In fission yeast, microtubules deliver the Tea1-Tea4 complex to mark cell poles for growth, but how this complex activates Cdc42 is unknown. Here, we show that ectopic targeting of Tea4 to cell sides promotes the local activation of Cdc42 and cell growth. This activity requires that Tea4 binds the type I phosphatase (PP1) catalytic subunit Dis2 or Sds21, and ectopic targeting of either catalytic subunit is similarly instructive for growth. The Cdc42 guanine-nucleotide-exchange factor Gef1 and the GTPase-activating protein Rga4 are required for Tea4-PP1-dependent ectopic growth. Gef1 is recruited to ectopic Tea4 and Dis2 locations to promote Cdc42 activation. By contrast, Rga4 is locally excluded by Tea4, and its forced colocalization with Tea4 blocks ectopic growth, indicating that Rga4 must be present, but at sites distinct from Tea4. Thus, a Tea4-PP1 landmark promotes local Cdc42 activation and growth both through Cdc42 GEF recruitment and by creating a local trough in a Cdc42 GAP.

PAF53 is essential in mammalian cells: CRISPR/Cas9 fails to eliminate PAF53 expression.

PubMed

Rothblum, Lawrence I; Rothblum, Katrina; Chang, Eugenie

2017-05-15

When mammalian cells are nutrient and/or growth factor deprived, exposed to inhibitors of protein synthesis, stressed by heat shock or grown to confluence, rDNA transcription is essentially shut off. Various mechanisms are available to accomplish this downshift in ribosome biogenesis. Muramatsu's laboratory (Hanada et al., 1996) first demonstrated that mammalian PAF53 was essential for specific rDNA transcription and that PAF53 levels were regulated in response to growth factors. While S. cerevisae A49, the homologue of vertebrate PAF53, is not essential for viability (Liljelund et al., 1992), deletion of yA49 results in colonies that grow at 6% of the wild type rate at 25°C. Experiments described by Wang et al. (2015) identified PAF53 as a gene "essential for optimal proliferation". However, they did not discriminate genes essential for viability. Hence, in order to resolve this question, we designed a series of experiments to determine if PAF53 was essential for cell survival. We set out to delete the gene product from mammalian cells using CRISPR/CAS9 technology. Human 293 cells were transfected with lentiCRISPR v2 carrying genes for various sgRNA that targeted PAF53. In some experiments, the cells were cotransfected in parallel with plasmids encoding FLAG-tagged mouse PAF53. After treating the transfected cells with puromycin (to select for the lentiCRISPR backbone), cells were cloned and analyzed by western blots for PAF53 expression. Genomic DNA was amplified across the "CRISPRd" exon, cloned and sequenced to identify mutated PAF53 genes. We obtained cell lines in which the endogenous PAF53 gene was "knocked out" only when we rescued with FLAG-PAF53. DNA sequencing demonstrated that in the absence of ectopic PAF53 expression, cells demonstrated unique means of surviving; including recombination or the utilization of alternative reading frames. We never observed a clone in which one PAF53 gene is expressed, unless there was also ectopic expression In the absence of ectopic gene expression, the gene products of both endogenous genes were expressed, irrespective of whether they were partially mutant proteins or not. Copyright © 2016 Elsevier B.V. All rights reserved.

E-cadherin-defective gastric cancer cells depend on Laminin to survive and invade.

PubMed

Caldeira, Joana; Figueiredo, Joana; Brás-Pereira, Catarina; Carneiro, Patrícia; Moreira, Ana M; Pinto, Marta T; Relvas, João B; Carneiro, Fátima; Barbosa, Mário; Casares, Fernando; Janody, Florence; Seruca, Raquel

2015-10-15

Epithelial-cadherin (Ecad) deregulation affects cell-cell adhesion and results in increased invasiveness of distinct human carcinomas. In gastric cancer, loss of Ecad expression is a common event and is associated with disease aggressiveness and poor prognosis. However, the molecular mechanisms underlying the invasive process associated to Ecad dysfunction are far from understood. We hypothesized that deregulation of cell-matrix interactions could play an important role during this process. Thus, we focussed on LM-332, which is a major matrix component, and in Ecad/LM-332 crosstalk in the process of Ecad-dependent invasion. To verify whether matrix deregulation was triggered by Ecad loss, we used the Drosophila model. To dissect the key molecules involved and unveil their functional significance, we used gastric cancer cell lines. The relevance of this relationship was then confirmed in human primary tumours. In vivo, Ecad knockdown induced apoptosis; nonetheless, at the invasive front, cells ectopically expressed Laminin A and βPS integrin. In vitro, we demonstrated that, in two different gastric cancer cell models, Ecad-defective cells overexpressed Laminin γ2 (LM-γ2), β1 and β4 integrin, when compared with Ecad-competent ones. We showed that LM-γ2 silencing impaired invasion and enhanced cell death, most likely via pSrc and pAkt reduction, and JNK activation. In human gastric carcinomas, we found a concomitant decrease in Ecad and increase in LM-γ2. This is the first evidence that ectopic Laminin expression depends on Ecad loss and allows Ecad-dysfunctional cells to survive and invade. This opens new avenues for using LM-γ2 signalling regulators as molecular targets to impair gastric cancer progression. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

MicroRNA-542-5p as a Novel Tumor Suppressor in Neuroblastoma

PubMed Central

Bray, Isabella; Tivnan, Amanda; Bryan, Kenneth; Foley, Niamh H; Watters, Karen M; Tracey, Lorraine; Davidoff, Andrew M; Stallings, Raymond L

2011-01-01

Several studies have implicated the dysregulation of microRNAs in neuroblastoma pathogenesis, an often fatal paediatric cancer arising from precursor cells of the sympathetic nervous system. Our group and others have demonstrated that lower expression of miR-542-5p is highly associated with poor patient survival, indicating a potential tumor suppressive function. Here, we demonstrate that ectopic over-expression of this miRNA decreases the invasive potential of neuroblastoma cell lines in vitro, along with primary tumor growth and metastases in an orthotopic mouse xenograft model, providing the first functional evidence for the involvement of miR-542-5p as a tumor suppressor in any type of cancer. PMID:21310526

Dexamethasone Enhances Osteogenic Differentiation of Bone Marrow- and Muscle-Derived Stromal Cells and Augments Ectopic Bone Formation Induced by Bone Morphogenetic Protein-2

PubMed Central

Yuasa, Masato; Yamada, Tsuyoshi; Taniyama, Takashi; Masaoka, Tomokazu; Xuetao, Wei; Yoshii, Toshitaka; Horie, Masaki; Yasuda, Hiroaki; Uemura, Toshimasa; Okawa, Atsushi; Sotome, Shinichi

2015-01-01

We evaluated whether dexamethasone augments the osteogenic capability of bone marrow-derived stromal cells (BMSCs) and muscle tissue-derived stromal cells (MuSCs), both of which are thought to contribute to ectopic bone formation induced by bone morphogenetic protein-2 (BMP-2), and determined the underlying mechanisms. Rat BMSCs and MuSCs were cultured in growth media with or without 10-7 M dexamethasone and then differentiated under osteogenic conditions with dexamethasone and BMP-2. The effects of dexamethasone on cell proliferation and osteogenic differentiation, and also on ectopic bone formation induced by BMP-2, were analyzed. Dexamethasone affected not only the proliferation rate but also the subpopulation composition of BMSCs and MuSCs, and subsequently augmented their osteogenic capacity during osteogenic differentiation. During osteogenic induction by BMP-2, dexamethasone also markedly affected cell proliferation in both BMSCs and MuSCs. In an in vivo ectopic bone formation model, bone formation in muscle-implanted scaffolds containing dexamethasone and BMP-2 was more than two fold higher than that in scaffolds containing BMP-2 alone. Our results suggest that dexamethasone potently enhances the osteogenic capability of BMP-2 and may thus decrease the quantity of BMP-2 required for clinical application, thereby reducing the complications caused by excessive doses of BMP-2. Highlights: 1. Dexamethasone induced selective proliferation of bone marrow- and muscle-derived cells with higher differentiation potential. 2. Dexamethasone enhanced the osteogenic capability of bone marrow- and muscle-derived cells by altering the subpopulation composition. 3. Dexamethasone augmented ectopic bone formation induced by bone morphogenetic protein-2. PMID:25659106

New Advanced Technologies in Stem Cell Therapy

DTIC Science & Technology

2013-09-01

infiltration in skeletal muscle. Ectopic fat accumulation in skeletal muscle can be seen not only in myopathies but also in several disorders...mice; however, the source of the ectopic fat tissue within the skeletal muscle is unknown. In this study, we provide evidence that the RACs, PDGFRα...mesenchymal progenitor cells, are responsible for increased fat cell formation in the skeletal muscle of dKO mice. We observed that dKO-RACs had

Alteration in Auxin Homeostasis and Signaling by Overexpression Of PINOID Kinase Causes Leaf Growth Defects in Arabidopsis thaliana

PubMed Central

Saini, Kumud; Markakis, Marios N.; Zdanio, Malgorzata; Balcerowicz, Daria M.; Beeckman, Tom; De Veylder, Lieven; Prinsen, Els; Beemster, Gerrit T. S.; Vissenberg, Kris

2017-01-01

In plants many developmental processes are regulated by auxin and its directional transport. PINOID (PID) kinase helps to regulate this transport by influencing polar recruitment of PIN efflux proteins on the cellular membranes. We investigated how altered auxin levels affect leaf growth in Arabidopsis thaliana. Arabidopsis mutants and transgenic plants with altered PID expression levels were used to study the effect on auxin distribution and leaf development. Single knockouts showed small pleiotropic growth defects. Contrastingly, several leaf phenotypes related to changes in auxin concentrations and transcriptional activity were observed in PID overexpression (PIDOE) lines. Unlike in the knockout lines, the leaves of PIDOE lines showed an elevation in total indole-3-acetic acid (IAA). Accordingly, enhanced DR5-visualized auxin responses were detected, especially along the leaf margins. Kinematic analysis revealed that ectopic expression of PID negatively affects cell proliferation and expansion rates, yielding reduced cell numbers and small-sized cells in the PIDOE leaves. We used PIDOE lines as a tool to study auxin dose effects on leaf development and demonstrate that auxin, above a certain threshold, has a negative affect on leaf growth. RNA sequencing further showed how subtle PIDOE-related changes in auxin levels lead to transcriptional reprogramming of cellular processes. PMID:28659952

[Cost-effectiveness analysis of laparoscopic surgery versus methotrexate: comparison of data recorded in an ectopic pregnancy registry].

PubMed

Vaissade, L; Gerbaud, L; Pouly, J-L; Job-Spira, N; Bouyer, J; Coste, J; Glanddier, P-Y

2003-09-01

To compare the cost efficacy ratios of medical therapy (methotrexate - MTX) and laparoscopic surgery for ectopic pregnancy, based on an observational study of effectiveness. Data were collected by a population register of the Auvergne area. We computed the costs before, during and after hospitalization of women who could be treated either by MTX or laparoscopic surgery. We detailed costs related to the various existing facilities. We considered the entire treatment. One hundred nine cases of ectopic pregnancy were treated by laparoscopic surgery and 46 by MTX. Second-line therapy was required in 3% of women who underwent laparoscopic surgery, and 35% of those given MTX. MTX was found to be less costly (1,342 euros) than laparoscopic surgery (2,113 euros). The efficacy threshold for MTX was 11% (giving a failure rate of 89%). MTX is much more cost effective than laparoscopic surgery but the frequent need for second-line treatment must also be assessed.

Formation of ectopic osteogenesis in weightlessness

NASA Technical Reports Server (NTRS)

1977-01-01

An ectopic osteogenesis experiment aboard the Cosmos-936 biosatellite is described. Decalcified, lyophilized femur and tibia were implanted under the fascia or in the anterior wall of the abdomen in rats. Bone formation before and after the tests is described and illustrated. The extent of formation of ectopic bone in weightlessness did not differ significantly from that in the ground controls, but the bone marrow of the ectopic bone of the flight rats consisted exclusively of fat cells. The deficit of support-muscle loading was considered to cause the disturbance in skeletal bone tissue development.

Establishment and transformation of telomerase-immortalized human small airway epithelial cells by heavy ions

NASA Astrophysics Data System (ADS)

Zhao, Y. L.; Piao, C. Q.; Hei, T. K.

Previous studies from this laboratory have identified a number of causally linked genes including the novel tumor suppressor Betaig-h3 that were differentially expressed in radiation induced tumorigenic BEP2D cells. To extend these studies using a genomically more stable bronchial cell line, we show here that ectopic expression of the catalytic subunit of telomerase (hTERT) in primary human small airway epithelial (SAE) cells resulted in the generation of several clonal cell lines that have been continuously in culture for more than 250 population doublings and are considered immortal. Comparably-treated control SAE cells infected with only the viral vector senesced after less than 10 population doublings. The immortalized clones demonstrated anchorage dependent growth and are non-tumorigenic in nude mice. These cells show no alteration in the p53 gene but a decrease in p16 expression. Exponentially growing SAEh cells were exposed to graded doses of 1 GeV/nucleon of 56Fe ions accelerated at the Brookhaven National Laboratory. Irradiated cells underwent gradual phenotypic alterations after extensive in vitro cultivation. Transformed cells developed through a series of successive steps before becoming anchorage independent in semisolid medium. These findings indicate that hTERT-immortalized cells, being diploid and chromosomal stable, should be a useful model in assessing mechanism of radiation carcinogenesis.

Intrinsic neurophysiological properties of hilar ectopic and normotopic dentate granule cells in human temporal lobe epilepsy and a rat model.

PubMed

Althaus, A L; Sagher, O; Parent, J M; Murphy, G G

2015-02-15

Hilar ectopic dentate granule cells (DGCs) are a salient feature of aberrant plasticity in human temporal lobe epilepsy (TLE) and most rodent models of the disease. Recent evidence from rodent TLE models suggests that hilar ectopic DGCs contribute to hyperexcitability within the epileptic hippocampal network. Here we investigate the intrinsic excitability of DGCs from humans with TLE and the rat pilocarpine TLE model with the objective of comparing the neurophysiology of hilar ectopic DGCs to their normotopic counterparts in the granule cell layer (GCL). We recorded from 36 GCL and 7 hilar DGCs from human TLE tissue. Compared with GCL DGCs, hilar DGCs in patient tissue exhibited lower action potential (AP) firing rates, more depolarized AP threshold, and differed in single AP waveform, consistent with an overall decrease in excitability. To evaluate the intrinsic neurophysiology of hilar ectopic DGCs, we made recordings from retrovirus-birthdated, adult-born DGCs 2-4 mo after pilocarpine-induced status epilepticus or sham treatment in rats. Hilar DGCs from epileptic rats exhibited higher AP firing rates than normotopic DGCs from epileptic or control animals. They also displayed more depolarized resting membrane potential and wider AP waveforms, indicating an overall increase in excitability. The contrasting findings between disease and disease model may reflect differences between the late-stage disease tissue available from human surgical specimens and the earlier disease stage examined in the rat TLE model. These data represent the first neurophysiological characterization of ectopic DGCs from human hippocampus and prospectively birthdated ectopic DGCs in a rodent TLE model. Copyright © 2015 the American Physiological Society.

Characterization of immortalized dairy goat male germline stem cells (mGSCs).

PubMed

Zhu, Haijing; Ma, Jing; Du, Rui; Zheng, Liming; Wu, Jiang; Song, Wencong; Niu, Zhiwei; He, Xin; Du, Enqi; Zhao, Shanting; Hua, Jinlian

2014-09-01

Male germline stem cells (mGSCs), in charge for the fertility in male testis, are the only kind of adult stem cells that transmit genetic information to next generation, with promising prospects in germplasm resources preservation and optimization, and production of transgenic animals. Mouse male germline stem cell lines have been established and are valuable for studying the mechanisms of spermatogenesis. However, there is a lack of stable mGSC cell lines in livestock, which restricts the progress of transgenic research and related biotechnology. Here, we firstly established an immortalized dairy goat mGSC cell line to study the biological properties and the signaling pathways associated with mGSCs self-renewal and differentiation. The ectopic factors SV40 large T antigen and Bmi1 genes were transduced into dairy goat mGSCs, and the results showed that the proliferation of these cells that were named mGSCs-I-SB was improved significantly. They maintained the typical characteristics including the expression of mGSC markers, and the potential to differentiate into all three germ layers, sperm-like cells in vitro. Additionally, mGSCs-I-SB survived and differentiated into three germ layer cell types when they were transplanted into chicken embryos. Importantly, the cells also survived in mouse spermatogenesis deficiency model testis which seemed to be the golden standard to examine mGSCs. Conclusively, our results demonstrate that mGSCs-I-SB present the characteristics of mGSCs and may promote the future study on goat mGSCs. © 2014 Wiley Periodicals, Inc.

FAM83D activates the MEK/ERK signaling pathway and promotes cell proliferation in hepatocellular carcinoma

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

Wang, Dong; Han, Sheng; Peng, Rui

2015-03-06

Publicly available microarray data suggests that the expression of FAM83D (Family with sequence similarity 83, member D) is elevated in a wide variety of tumor types, including hepatocellular carcinoma (HCC). However, its role in the pathogenesis of HCC has not been elucidated. Here, we showed that FAM83D was frequently up-regulated in HCC samples. Forced FAM83D expression in HCC cell lines significantly promoted their proliferation and colony formation while FAM83D knockdown resulted in the opposite effects. Mechanistic analyses indicated that FAM83D was able to activate the MEK/ERK signaling pathway and promote the entry into S phase of cell cycle progression. Takenmore » together, these results demonstrate that FAM83D is a novel oncogene in HCC development and may constitute a potential therapeutic target in HCC. - Highlights: • FAM83D is up-regulated in HCC tissues and cell lines. • Ectopic expression of FAM83D promotes HCC cell proliferation and colony formation. • Depletion of FAM83D inhibits HCC cell proliferation and colony formation. • FAM83D activates the MEK/ERK signaling pathway in HCC.« less

HLS7, a hemopoietic lineage switch gene homologous to the leukemia-inducing gene MLF1.

PubMed Central

Williams, J H; Daly, L N; Ingley, E; Beaumont, J G; Tilbrook, P A; Lalonde, J P; Stillitano, J P; Klinken, S P

1999-01-01

Hemopoietic lineage switching occurs when leukemic cells, apparently committed to one lineage, change and display the phenotype of another pathway. cDNA representational difference analysis was used to identify myeloid-specific genes that may be associated with an erythroid to myeloid lineage switch involving the murine J2E erythroleukemic cell line. One of the genes isolated (HLS7) is homologous to the novel human oncogene myeloid leukemia factor 1 (MLF1) involved in the t(3;5)(q25.1;q34) translocation associated with acute myeloid leukemia. Enforced expression of HLS7 in J2E cells induced a monoblastoid phenotype, thereby recapitulating the spontaneous erythroid to myeloid lineage switch. HLS7 also inhibited erythropoietin- or chemically-induced differentiation of erythroleukemic cell lines and suppressed development of erythropoietin-responsive colonies in semi-solid culture. However, intracellular signaling activated by erythropoietin was not impeded by ectopic expression of HLS7. In contrast, HLS7 promoted maturation of M1 monoblastoid cells and increased myeloid colony formation in vitro. These data show that HLS7 can influence erythroid/myeloid lineage switching and the development of normal hemopoietic cells. PMID:10523300

HLS7, a hemopoietic lineage switch gene homologous to the leukemia-inducing gene MLF1.

PubMed

Williams, J H; Daly, L N; Ingley, E; Beaumont, J G; Tilbrook, P A; Lalonde, J P; Stillitano, J P; Klinken, S P

1999-10-15

Hemopoietic lineage switching occurs when leukemic cells, apparently committed to one lineage, change and display the phenotype of another pathway. cDNA representational difference analysis was used to identify myeloid-specific genes that may be associated with an erythroid to myeloid lineage switch involving the murine J2E erythroleukemic cell line. One of the genes isolated (HLS7) is homologous to the novel human oncogene myeloid leukemia factor 1 (MLF1) involved in the t(3;5)(q25.1;q34) translocation associated with acute myeloid leukemia. Enforced expression of HLS7 in J2E cells induced a monoblastoid phenotype, thereby recapitulating the spontaneous erythroid to myeloid lineage switch. HLS7 also inhibited erythropoietin- or chemically-induced differentiation of erythroleukemic cell lines and suppressed development of erythropoietin-responsive colonies in semi-solid culture. However, intracellular signaling activated by erythropoietin was not impeded by ectopic expression of HLS7. In contrast, HLS7 promoted maturation of M1 monoblastoid cells and increased myeloid colony formation in vitro. These data show that HLS7 can influence erythroid/myeloid lineage switching and the development of normal hemopoietic cells.

miR-124 radiosensitizes human esophageal cancer cell TE-1 by targeting CDK4.

PubMed

Zhang, Y H; Wang, Q Q; Li, H; Ye, T; Gao, F; Liu, Y C

2016-06-03

Radiotherapy is one of the most important treatments for esophageal cancer, but radioresistance remains a major challenge. Previous studies have shown that microRNAs (miRNAs or miRs) are involved in human cancers. miR-124 has been widely reported in various cancers and it is intimately involved in proliferation, cell cycle regulation, apoptosis, migration, and invasion of cancer cells. The aim of this study was to explore the relationship between the miR-124/cyclin-dependent kinase 4 (CDK4) axis and the radiosensitivity of esophageal cancer cells. In this study, we identified the reduced expression of miR-124 in 18 paired esophageal cancer tissues compared to their matched normal tissues. In order to investigate the physiological role of miR-124 in esophageal cancer, the cell counting kit-8 (CCK-8) assay and wound healing assay were performed, and the results suggest that miR-124 overexpression decreases tumor growth and aggression. Next, we detected the effects of ectopic miR-124 expression on the apoptosis of an esophageal cancer cell line (TE-1) following radiotherapy. Using the CCK-8 assay and Hoechst 332528 stain, we found that ectopic expression of miR-124 led to a higher percentage of apoptotic cells. Finally, we identified that CDK4 is a direct target of miR-124 in TE-1 cells using target prediction algorithms and a luciferase reporter assay. Moreover, western blot assay confirmed that CDK4 was downregulated during miR-124 transfection. Taken together, we illustrate that the miR-124/CDK4 axis plays an important role in radiation sensitivity of human esophageal cancer cells by targeting CDK4.

Overexpression of hTERT increases stem-like properties and decreases spontaneous differentiation in human mesenchymal stem cell lines

PubMed Central

2010-01-01

To overcome loss of stem-like properties and spontaneous differentiation those hinder the expansion and application of human mesenchymal stem cells (hMSCs), we have clonally isolated permanent and stable human MSC lines by ectopic overexpression of primary cell cultures of hMSCs with HPV 16 E6E7 and human telomerase reverse transcriptase (hTERT) genes. These cells were found to have a differentiation potential far beyond the ordinary hMSCs. They expressed trophoectoderm and germline specific markers upon differentiation with BMP4 and retinoic acid, respectively. Furthermore, they displayed higher osteogenic and neural differentiation efficiency than primary hMSCs or hMSCs expressed HPV16 E6E7 alone with a decrease in methylation level as proven by a global CpG island methylation profile analysis. Notably, the demethylated CpG islands were highly associated with development and differentiation associated genes. Principal component analysis further pointed out the expression profile of the cells converged toward embryonic stem cells. These data demonstrate these cells not only are a useful tool for the studies of cell differentiation both for the mesenchymal and neurogenic lineages, but also provide a valuable source of cells for cell therapy studies in animal models of skeletal and neurological disorders. PMID:20670406

miR-297 modulates multidrug resistance in human colorectal carcinoma by down-regulating MRP-2.

PubMed

Xu, Ke; Liang, Xin; Shen, Ke; Cui, Daling; Zheng, Yuanhong; Xu, Jianhua; Fan, Zhongze; Qiu, Yanyan; Li, Qi; Ni, Lei; Liu, Jianwen

2012-09-01

Colorectal carcinoma is a frequent cause of cancer-related death in men and women. miRNAs (microRNAs) are endogenous small non-coding RNAs that regulate gene expression negatively at the post-transcriptional level. In the present study we investigated the possible role of microRNAs in the development of MDR (multidrug resistance) in colorectal carcinoma cells. We analysed miRNA expression levels between MDR colorectal carcinoma cell line HCT116/L-OHP cells and their parent cell line HCT116 using a miRNA microarray. miR-297 showed lower expression in HCT116/L-OHP cells compared with its parental cells. MRP-2 (MDR-associated protein 2) is an important MDR protein in platinum-drug-resistance cells and is a predicted target of miR-297. Additionally miR-297 was down-regulated in a panel of human colorectal carcinoma tissues and negatively correlated with expression levels of MRP-2. Furthermore, we found that ectopic expression of miR-297 in MDR colorectal carcinoma cells reduced MRP-2 protein level and sensitized these cells to anti-cancer drugs in vitro and in vivo. Taken together, our findings suggest that miR-297 could play a role in the development of MDR in colorectal carcinoma cells, at least in part by modulation of MRP-2.

Functional neurons and melanocytes induced from immortal lines of postnatal neural crest-like stem cells.

PubMed

Sviderskaya, Elena V; Easty, David J; Lawrence, Mark A; Sánchez, Daniel P; Negulyaev, Yuri A; Patel, Ricken H; Anand, Praveen; Korchev, Yuri E; Bennett, Dorothy C

2009-09-01

Stem cells, that is, cells that can both reproduce themselves and differentiate into functional cell types, attract much interest as potential aids to healing and disease therapy. Embryonic neural crest is pluripotent and generates the peripheral nervous system, melanocytes, and some connective tissues. Neural-crest-related stem cells have been reported previously in postnatal skin: committed melanocytic stem cells in the hair follicle, and pluripotent cell types from the hair follicle and papilla that can produce various sets of lineages. Here we describe novel pluripotent neural crest-like stem cells from neonatal mouse epidermis, with different potencies, isolated as 3 independent immortal lines. Using alternative regulatory factors, they could be converted to large numbers of either Schwann precursor cells, pigmented melanocytes, chondrocytes, or functional sensory neurons showing voltage-gated sodium channels. Some of the neurons displayed abundant active TRPV1 and TRPA1 receptors. Such functional neurons have previously been obtained in culture only with difficulty, by explantation. The system was also used to generate comparative gene expression data for the stem cells, melanocytes, and melanoblasts that sufficiently explain the lack of pigment in melanoblasts and provide a rationale for some genes expressed apparently ectopically in melanomas, such as ephrin receptors.

The Metastasis Efficiency Modifier Ribosomal RNA Processing 1 Homolog B (RRP1B) Is a Chromatin-associated Factor*

PubMed Central

Crawford, Nigel P. S.; Yang, Hailiu; Mattaini, Katherine R.; Hunter, Kent W.

2009-01-01

There is accumulating evidence for a role of germ line variation in breast cancer metastasis. We have recently identified a novel metastasis susceptibility gene, Rrp1b (ribosomal RNA processing 1 homolog B). Overexpression of Rrp1b in a mouse mammary tumor cell line induces a gene expression signature that predicts survival in breast cancer. Here we extend the analysis of RRP1B function by demonstrating that the Rrp1b activation gene expression signature accurately predicted the outcome in three of four publicly available breast carcinoma gene expression data sets. In addition, we provide insights into the mechanism of RRP1B. Tandem affinity purification demonstrated that RRP1B physically interacts with many nucleosome binding factors, including histone H1X, poly(ADP-ribose) polymerase 1, TRIM28 (tripartite motif-containing 28), and CSDA (cold shock domain protein A). Co-immunofluorescence and co-immunoprecipitation confirmed these interactions and also interactions with heterochromatin protein-1α and acetyl-histone H4 lysine 5. Finally, we investigated the effects of ectopic expression of an RRP1B allelic variant previously associated with improved survival in breast cancer. Gene expression analyses demonstrate that, compared with ectopic expression of wild type RRP1B in HeLa cells, the variant RRP1B differentially modulates various transcription factors controlled by TRIM28 and CSDA. These data suggest that RRP1B, a tumor progression and metastasis susceptibility candidate gene, is potentially a dynamic modulator of transcription and chromatin structure. PMID:19710015

PIK3CA dependence and sensitivity to therapeutic targeting in urothelial carcinoma.

PubMed

Ross, R L; McPherson, H R; Kettlewell, L; Shnyder, S D; Hurst, C D; Alder, O; Knowles, M A

2016-07-28

Many urothelial carcinomas (UC) contain activating PIK3CA mutations. In telomerase-immortalized normal urothelial cells (TERT-NHUC), ectopic expression of mutant PIK3CA induces PI3K pathway activation, cell proliferation and cell migration. However, it is not clear whether advanced UC tumors are PIK3CA-dependent and whether PI3K pathway inhibition is a good therapeutic option in such cases. We used retrovirus-mediated delivery of shRNA to knock down mutant PIK3CA in UC cell lines and assessed effects on pathway activation, cell proliferation, migration and tumorigenicity. The effect of the class I PI3K inhibitor GDC-0941 was assessed in a panel of UC cell lines with a range of known molecular alterations in the PI3K pathway. Specific knockdown of PIK3CA inhibited proliferation, migration, anchorage-independent growth and in vivo tumor growth of cells with PIK3CA mutations. Sensitivity to GDC-0941 was dependent on hotspot PIK3CA mutation status. Cells with rare PIK3CA mutations and co-occurring TSC1 or PTEN mutations were less sensitive. Furthermore, downstream PI3K pathway alterations in TSC1 or PTEN or co-occurring AKT1 and RAS gene mutations were associated with GDC-0941 resistance. Mutant PIK3CA is a potent oncogenic driver in many UC cell lines and may represent a valuable therapeutic target in advanced bladder cancer.

Metabolic determinants of cancer cell sensitivity to glucose limitation and biguanides

NASA Astrophysics Data System (ADS)

Birsoy, Kıvanç; Possemato, Richard; Lorbeer, Franziska K.; Bayraktar, Erol C.; Thiru, Prathapan; Yucel, Burcu; Wang, Tim; Chen, Walter W.; Clish, Clary B.; Sabatini, David M.

2014-04-01

As the concentrations of highly consumed nutrients, particularly glucose, are generally lower in tumours than in normal tissues, cancer cells must adapt their metabolism to the tumour microenvironment. A better understanding of these adaptations might reveal cancer cell liabilities that can be exploited for therapeutic benefit. Here we developed a continuous-flow culture apparatus (Nutrostat) for maintaining proliferating cells in low-nutrient media for long periods of time, and used it to undertake competitive proliferation assays on a pooled collection of barcoded cancer cell lines cultured in low-glucose conditions. Sensitivity to low glucose varies amongst cell lines, and an RNA interference (RNAi) screen pinpointed mitochondrial oxidative phosphorylation (OXPHOS) as the major pathway required for optimal proliferation in low glucose. We found that cell lines most sensitive to low glucose are defective in the OXPHOS upregulation that is normally caused by glucose limitation as a result of either mitochondrial DNA (mtDNA) mutations in complex I genes or impaired glucose utilization. These defects predict sensitivity to biguanides, antidiabetic drugs that inhibit OXPHOS, when cancer cells are grown in low glucose or as tumour xenografts. Notably, the biguanide sensitivity of cancer cells with mtDNA mutations was reversed by ectopic expression of yeast NDI1, a ubiquinone oxidoreductase that allows bypass of complex I function. Thus, we conclude that mtDNA mutations and impaired glucose utilization are potential biomarkers for identifying tumours with increased sensitivity to OXPHOS inhibitors.

Expression of the cancer-testis antigen BORIS correlates with prostate cancer.

PubMed

Cheema, Zubair; Hari-Gupta, Yukti; Kita, Georgia-Xanthi; Farrar, Dawn; Seddon, Ian; Corr, John; Klenova, Elena

2014-02-01

BORIS, a paralogue of the transcription factor CTCF, is a member of the cancer-testis antigen (CT) family. BORIS is normally present at high levels in the testis; however it is aberrantly expressed in various tumors and cancer cell lines. The main objectives of this study were to investigate BORIS expression together with sub-cellular localization in both prostate cell lines and tumor tissues, and assess correlations between BORIS and clinical/pathological characteristics. We examined BORIS mRNA expression, protein levels and cellular localization in a panel of human prostate tissues, cancer and benign, together with a panel prostate cell lines. We also compared BORIS levels and localization with clinical/pathological characteristics in prostate tumors. BORIS was detected in all inspected prostate cancer cell lines and tumors, but was absent in benign prostatic hyperplasia. Increased levels of BORIS protein positively correlated with Gleason score, T-stage and androgen receptor (AR) protein levels in prostate tumors. The relationship between BORIS and AR was further highlighted in prostate cell lines by the ability of ectopically expressed BORIS to activate the endogenous AR mRNA and protein. BORIS localization in the nucleus plus cytoplasm was also associated with higher BORIS levels and Gleason score. Detection of BORIS in prostate tumors suggests potential applications of BORIS as a biomarker for prostate cancer diagnosis, as an immunotherapy target and, potentially, a prognostic marker of more aggressive prostate cancer. The ability of BORIS to activate the AR gene indicates BORIS involvement in the growth and development of prostate tumors. © 2013 Wiley Periodicals, Inc.

Functions of ectopically transplanted invasive horse trophoblast

PubMed Central

de Mestre, Amanda M.; Hanlon, David; Adams, A. Paige; Runcan, Erin; Leadbeater, Jane C.; Erb, Hollis N.; Costa, Christina C.; Miller, Donald; Allen, W. R; Antczak, Douglas F.

2013-01-01

The invasive and fully antigenic trophoblast of the chorionic girdle portion of the equine fetal membranes has the capacity to survive and differentiate after transplantation to ectopic sites. The objectives of this study were to determine: (i) the survival time of ectopically transplanted allogeneic trophoblast cells in non-pregnant recipient mares, (ii) whether equine Chorionic Gonadotrophin (eCG) can be delivered systemically by transplanted chorionic girdle cells, and (iii) if eCG delivered by the transplanted cells is biologically active and can suppress behavioral signs associated with estrus. Ectopically transplanted chorionic girdle survived for up to 105 days with a mean lifespan of 75 days (95% CI 55–94), and secreted sufficient eCG for the hormone to be measurable in the recipients’ circulation. Immunohistochemical labeling of serial biopsies of the transplant sites and measurement of eCG profiles demonstrated that graft survival was similar to the lifespan of equine endometrial cups in normal horse pregnancy. The eCG secreted by the transplanted cells induced corpora lutea formation and sustained systemic progesterone levels in the recipient mares, effects that are also observed during pregnancy. This in turn caused suppression of estrus behavior in the recipients for up to three months. Thus, ectopically transplanted equine trophoblast provides an unusual example of sustained viability and function of an immunogenic transplant in a recipient with an intact immune system. This model highlights the importance of innate immunoregulatory capabilities of invasive trophoblast cells and describes a new method to deliver sustained circulating concentrations of eCG in non-pregnant mares. PMID:21389079

Identification of the receptor tyrosine kinase AXL in breast cancer as a target for the human miR-34a microRNA

PubMed Central

Mackiewicz, Mark; Huppi, Konrad; Pitt, Jason J.; Dorsey, Tiffany H.; Ambs, Stefan

2012-01-01

The identification of molecular features that contribute to the progression of breast cancer can provide valuable insight into the pathogenesis of this disease. Deregulated microRNA expression represents one type of molecular event that has been associated with many different human cancers. In order to identify a miRNA/mRNA regulatory interaction that is biologically relevant to the triple-negative breast cancer genotype/phenotype, we initially conducted a miRNA profiling experiment to detect differentially expressed miRNAs in cell line models representing triple-negative (MDA-MB-231), ER+ (MCF7), and HER-2 over expressed (SK-BR-3) histotypes. We identified human miR-34a expression as being >3-fold down (from its median expression value across all cell lines) in MDA-MB-231 cells, and identified AXL as a putative mRNA target using multiple miRNA/target prediction algorithms. The miR-34a/AXL interaction was functionally characterized through ectopic over expression experiments with a miR-34a mimic in two independent triple-negative breast cancer cell lines. In reporter assays, miR-34a binds to its putative target site within the AXL 3′UTR to inhibit luciferase expression. We also observed degradation of AXL mRNA and decreased AXL protein levels, as well as cell signaling effects on AKT phosphorylation and phenotypic effects on cell migration. Finally, we present an inverse correlative trend in miR-34a and AXL expression for both cell line and patient tumor samples. PMID:21814748

The homing of bone marrow MSCs to non-osseous sites for ectopic bone formation induced by osteoinductive calcium phosphate

PubMed Central

Song, Guodong; Habibovic, Pamela; Bao, Chongyun; Hu, Jing; van Blitterswijk, Clemens A.; Yuan, Huipin; Chen, Wenchuan; Xu, Hockin H.K.

2013-01-01

Osteoinductive biomaterials are promising for bone repair. There is no direct proof that bone marrow mesenchymal stem cells (BMSCs) home to non-osseous sites and participate in ectopic bone formation induced by osteoinductive bioceramics. The objective of this study was to use a sex-mismatched beagle dog model to investigate BMSC homing via blood circulation to participate in ectopic bone formation via osteoinductive biomaterial. BMSCs of male dogs were injected into female femoral marrow cavity. The survival and stable chimerism of donor BMSCs in recipients were confirmed with polymerase chain reaction (PCR) and fluorescence in situ hybridization (FISH). Biphasic calcium phosphate (BCP) granules were implanted in dorsal muscles of female dogs. Y chromosomes were detected in samples harvested from female dogs which had received male BMSCs. At 4 weeks, cells with Y-chromosomes were distributed in the new bone matrix throughout the BCP granule implant. At 6 weeks, cells with Y chromosomes were present in newly mineralized woven bone. TRAP positive osteoclast-like cells were observed in 4-week implants, and the number of such cells decreased from 4 to 6 weeks. These results show that osteoprogenitors were recruited from bone marrow and homed to ectopic site to serve as a cell source for calcium phosphate-induced bone formation. In conclusion, BMSCs were demonstrated to migrate from bone marrow through blood circulation to non-osseous bioceramic implant site to contribute to ectopic bone formation in a canine model. BCP induced new bone in muscles without growth factor delivery, showing excellent osteoinductivity that could be useful for bone tissue engineering. PMID:23298780

E-cadherin-defective gastric cancer cells depend on Laminin to survive and invade

PubMed Central

Caldeira, Joana; Figueiredo, Joana; Brás-Pereira, Catarina; Carneiro, Patrícia; Moreira, Ana M.; Pinto, Marta T.; Relvas, João B.; Carneiro, Fátima; Barbosa, Mário; Casares, Fernando; Janody, Florence; Seruca, Raquel

2015-01-01

Epithelial-cadherin (Ecad) deregulation affects cell–cell adhesion and results in increased invasiveness of distinct human carcinomas. In gastric cancer, loss of Ecad expression is a common event and is associated with disease aggressiveness and poor prognosis. However, the molecular mechanisms underlying the invasive process associated to Ecad dysfunction are far from understood. We hypothesized that deregulation of cell–matrix interactions could play an important role during this process. Thus, we focussed on LM-332, which is a major matrix component, and in Ecad/LM-332 crosstalk in the process of Ecad-dependent invasion. To verify whether matrix deregulation was triggered by Ecad loss, we used the Drosophila model. To dissect the key molecules involved and unveil their functional significance, we used gastric cancer cell lines. The relevance of this relationship was then confirmed in human primary tumours. In vivo, Ecad knockdown induced apoptosis; nonetheless, at the invasive front, cells ectopically expressed Laminin A and βPS integrin. In vitro, we demonstrated that, in two different gastric cancer cell models, Ecad-defective cells overexpressed Laminin γ2 (LM-γ2), β1 and β4 integrin, when compared with Ecad-competent ones. We showed that LM-γ2 silencing impaired invasion and enhanced cell death, most likely via pSrc and pAkt reduction, and JNK activation. In human gastric carcinomas, we found a concomitant decrease in Ecad and increase in LM-γ2. This is the first evidence that ectopic Laminin expression depends on Ecad loss and allows Ecad-dysfunctional cells to survive and invade. This opens new avenues for using LM-γ2 signalling regulators as molecular targets to impair gastric cancer progression. PMID:26246502

Mammalian-enabled (MENA) protein enhances oncogenic potential and cancer stem cell-like phenotype in hepatocellular carcinoma cells.

PubMed

Hu, Kunpeng; Huang, Pinzhu; Luo, Hui; Yao, Zhicheng; Wang, Qingliang; Xiong, Zhiyong; Lin, Jizong; Huang, He; Xu, Shilei; Zhang, Peng; Liu, Bo

2017-08-01

Mammalian-enabled (MENA) protein is an actin-regulatory protein that influences cell motility and adhesion. It is known to play a role in tumorigenicity of hepatocellular carcinoma (HCC) but the underlying molecular mechanism remains unknown. This study aimed to investigate the oncogenic potential of MENA and its capacity to regulate cancer stem cell (CSC)-like phenotypes in HCC cells. Real-time-PCR and western blot were used to assess mRNA and protein levels of target genes in human HCC tissue specimens and HCC cell lines, respectively. Stable MENA-overexpressing HCC cells were generated from HCC cell lines. Transwell cell migration and colony formation assays were employed to evaluate tumorigenicity. Ectopic expression of MENA significantly enhanced cell migration and colony-forming ability in HCC cells. Overexpression of MENA upregulated several hepatic progenitor/stem cell markers in HCC cells. A high MENA protein level was associated with high mRNA levels of MENA, CD133, cytokeratin 19 (CK19), and epithelial cell adhesion molecule (EpCAM) in human HCC tissues. Overexpression of MENA enhanced epithelial-to-mesenchymal transition (EMT) markers, extracellular signal-regulated kinases (ERK) phosphorylation, and the level of β-catenin in HCC cells. This study demonstrated that overexpression of MENA in HCC cells promoted stem cell markers, EMT markers, and tumorigenicity. These effects may involve, at least partially, the ERK and β-catenin signaling pathways.

BOLITA, an Arabidopsis AP2/ERF-like transcription factor that affects cell expansion and proliferation/differentiation pathways.

PubMed

Marsch-Martinez, Nayelli; Greco, Raffaella; Becker, Jörg D; Dixit, Shital; Bergervoet, Jan H W; Karaba, Aarati; de Folter, Stefan; Pereira, Andy

2006-12-01

The BOLITA (BOL) gene, an AP2/ERF transcription factor, was characterized with the help of an activation tag mutant and overexpression lines in Arabidopsis and tobacco. The leaf size of plants overexpressing BOL was smaller than wild type plants due to a reduction in both cell size and cell number. Moreover, severe overexpressors showed ectopic callus formation in roots. Accordingly, global gene expression analysis using the overexpression mutant reflected the alterations in cell proliferation, differentiation and growth through expression changes in RBR, CYCD, and TCP genes, as well as genes involved in cell expansion (i.e. expansins and the actin remodeling factor ADF5). Furthermore, the expression of hormone signaling (i.e. auxin and cytokinin), biosynthesis (i.e. ethylene and jasmonic acid) and regulatory genes was found to be perturbed in bol-D mutant leaves.

p21Waf1/Cip1/Sdi1 Prevents Apoptosis as Well as Stimulates Growth in Cells Transformed or Immortalized by Human T-Cell Leukemia Virus Type 1-Encoded Tax

PubMed Central

Kawata, Sanae; Ariumi, Yasuo; Shimotohno, Kunitada

2003-01-01

Human T-cell leukemia virus type 1 (HTLV-1) Tax regulates the expression of virally encoded genes, as well as various endogenous host genes in trans. Tax-mediated regulation of gene expression is important for the immortalization of normal human T lymphocytes and the transformation of fibroblast cells, such as Rat-1 cells. Tax has the ability to transactivate p21Waf1/Cip1/Sdi1, resulting in high expression levels in HTLV-1-immortalized cells. Since p21 expression is suppressed due to methylation of the promoter region in Rat-l cell line, p21 may not be critical for the transformation of this cell line by Tax. To further understand the role of p21 for the proliferation of Tax-transformed Rat-1 cells, we examined the effect of ectopic expression of p21 in these cells. Here, we observed that p21 expression enhanced the transformation of this cell line via at least two mechanisms: (i) the enhancement of NF-κB activation and/or CREB signaling and (ii) the excitation of antiapoptotic machinery. To analyze the role of p21 that is overexpressed in HTLV-1-immortalized lymphocytes, p21 expression was suppressed by using an antisense oligonucleotide specific for p21 mRNA; these cells then became sensitive to apoptotic induction. These results suggest that p21 plays an important role in the proliferation of Tax-expressing cells through the regulation of at least two independent mechanisms. PMID:12805427

microRNA-133 inhibits cell proliferation, migration and invasion in prostate cancer cells by targeting the epidermal growth factor receptor.

PubMed

Tao, Jun; Wu, Deyao; Xu, Bin; Qian, Weichun; Li, Pengchao; Lu, Qiang; Yin, Changjun; Zhang, Wei

2012-06-01

It has been shown that regulation of EGFR expression in prostate cancer cells is mostly at the transcriptional level. microRNA-133 (miR-133) has long been recognized as a muscle-specific miRNA which may regulate myoblast differentiation and participate in many myogenic diseases. Recently, it has been reported that miR-133 is also involved in other tumors, such as bladder cancer, esophageal cancer and may regulate cell motility in these cancer cells. In the present study, we examined the expression and effects of miR-133 in two hormone-insensitive prostate cancer cell lines. The expression of miR-133a and miR-133b were analyzed by quantitative RT-PCR. After transfection of miR-133a and miR-133b, cell viability assay, luciferase assay, western blot analysis, cell migration and invasion assay were conducted in Du145 and PC3 cells. In this study, we showed that miR‑133a and miR-133b are expressed at the detection limit in two hormone-insensitive prostate cancer cell lines, PC3 and DU145. Ectopic expression of miR-133 inhibited cell proliferation, migration and invasion in these cells. We also provide the first evidence that miR-133 may target EGFR. Our study provided the first glimpse of the functional role of miR-133 in two hormone-independent prostate cancer cell lines. These results may add to our knowledge on the molecular basis of prostate cancer progression.

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

Guo, Guoli; Yao, Guangmin; Zhan, Guanqun

We previously reported the isolation of a novel Amaryllidaceae alkaloid, N-methylhemeanthidine chloride (NMHC), from Zephyranthes candida, which exhibits potent cytotoxicity in a spectrum of tumor cells. However, the mechanism of action remains unclear. Using multiple cell lines derived from human pancreatic cancer, one of the most mortal and refractory human malignancies, we further studied the NMHC-mediated cytotoxicity and found that it induced drastic cytotoxicity in pancreatic cancer cells whereas an insignificant effect on a noncancerous cell line. The NMHC-mediated growth inhibition was more severe than the first-line chemotherapeutic agent gemcitabine, leading to cell cycle arrest, apoptotic death and decreased glycolysis.more » NMHC exerted its function through down-regulating AKT activation, and the ectopic expression of activated AKT rescued the growth inhibition. Consistently, NMHC injections in a pancreatic cancer xenograft model manifested the anti-tumor effect in vivo. Engrafted tumor cells underwent AKT attenuation and apoptotic death upon treatments. As such, we here demonstrate the AKT inhibition may be one of the mechanisms by which NMHC decreases tumor cell survival rate in vitro and in vivo. Our data thereby suggest that NMHC holds great promise as a potent chemotherapeutic agent against pancreatic cancer and sheds new light on obtaining such agents from natural products toward therapeutic purposes. - Highlights: • N-methylhemeanthidine chloride (NMHC) is a novel Amaryllidaceae alkaloid. • NMHC exhibits potent anti-neoplastic activity. • NMHC leads to cell cycle arrest, apoptotic death and decreased metabolism. • NMHC down-regulates the AKT signaling pathway.« less

A novel 3p22.3 gene CMTM7 represses oncogenic EGFR signaling and inhibits cancer cell growth.

PubMed

Li, H; Li, J; Su, Y; Fan, Y; Guo, X; Li, L; Su, X; Rong, R; Ying, J; Mo, X; Liu, K; Zhang, Z; Yang, F; Jiang, G; Wang, J; Zhang, Y; Ma, D; Tao, Q; Han, W

2014-06-12

Deletion of 3p12-22 is frequent in multiple cancer types, indicating the presence of critical tumor-suppressor genes (TSGs) at this region. We studied a novel candidate TSG, CMTM7, located at the 3p22.3 CMTM-gene cluster, for its tumor-suppressive functions and related mechanisms. The three CMTM genes, CMTM6, 7 and 8, are broadly expressed in human normal adult tissues and normal epithelial cell lines. Only CMTM7 is frequently silenced or downregulated in esophageal and nasopharyngeal cell lines, but uncommon in other carcinoma cell lines. Immunostaining of tissue microarrays for CMTM7 protein showed its downregulation or absence in esophageal, gastric, pancreatic, liver, lung and cervix tumor tissues. Promoter CpG methylation and loss of heterozygosity were both found contributing to CMTM7 downregulation. Ectopic expression of CMTM7 in carcinoma cells inhibits cell proliferation, motility and tumor formation in nude mice, but not in immortalized normal cells, suggesting a tumor inhibitory role of CMTM7. The tumor-suppressive function of CMTM7 is associated with its role in G1/S cell cycle arrest, through upregulating p27 and downregulating cyclin-dependent kinase 2 (CDK2) and 6 (CDK6). Moreover, CMTM7 could promote epidermal growth factor receptor (EGFR) internalization, and further suppress AKT signaling pathway. Thus, our findings suggest that CMTM7 is a novel 3p22 tumor suppressor regulating G1/S transition and EGFR/AKT signaling during tumor pathogenesis.

Negative Effects of SRD5A1 on Nuclear Activity of Progesterone Receptor Isoform B in JEG3 Cells.

PubMed

Miao, Zhuo; Sun, Min; Jiang, Feng; Yao, Yuanqing; Li, Yi

2016-02-01

Progesterone withdrawal signals labor in mammals. Elevated intracellular metabolism contributes to progesterone functional withdrawal through unknown mechanism, which is thought to act via progesterone receptor (PR). This study aims to investigate molecular mechanisms underlying progesterone withdrawal during pregnancy and labor. We investigated the role of 5α-reductase type I (SRD5A1) in enzymatic catalysis of progesterone and loss of PR function in a human trophoblast choriocarcinoma cell line JEG3. The PR isoform B (PR-B) was robustly expressed in JEG3 cells. The SRD5A1 small-interfering RNA knockdown led to significant increase in PR-B nuclear import, ectopic, whereas SRD5A1 overexpression resulted in remarkable inhibition of nuclear PR-B in P4-treated cells. Repression of SRD5A1 activated PR-B responsive gene, whereas overexpression of SRD5A1 possessed an inhibitory effect. JEG3 cell line is a valuable tool to study mechanisms responsible for loss of PR function and screening of drugs for preterm birth treatment. Our study aims to investigate the molecular mechanisms underlying progesterone withdrawal during pregnancy and labor. © The Author(s) 2015.

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

PubMed

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

2012-02-01

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

Generation of hyaline cartilaginous tissue from mouse adult dermal fibroblast culture by defined factors

PubMed Central

Hiramatsu, Kunihiko; Sasagawa, Satoru; Outani, Hidetatsu; Nakagawa, Kanako; Yoshikawa, Hideki; Tsumaki, Noriyuki

2011-01-01

Repair of cartilage injury with hyaline cartilage continues to be a challenging clinical problem. Because of the limited number of chondrocytes in vivo, coupled with in vitro de-differentiation of chondrocytes into fibrochondrocytes, which secrete type I collagen and have an altered matrix architecture and mechanical function, there is a need for a novel cell source that produces hyaline cartilage. The generation of induced pluripotent stem (iPS) cells has provided a tool for reprogramming dermal fibroblasts to an undifferentiated state by ectopic expression of reprogramming factors. Here, we show that retroviral expression of two reprogramming factors (c-Myc and Klf4) and one chondrogenic factor (SOX9) induces polygonal chondrogenic cells directly from adult dermal fibroblast cultures. Induced cells expressed marker genes for chondrocytes but not fibroblasts, i.e., the promoters of type I collagen genes were extensively methylated. Although some induced cell lines formed tumors when subcutaneously injected into nude mice, other induced cell lines generated stable homogenous hyaline cartilage–like tissue. Further, the doxycycline-inducible induction system demonstrated that induced cells are able to respond to chondrogenic medium by expressing endogenous Sox9 and maintain chondrogenic potential after substantial reduction of transgene expression. Thus, this approach could lead to the preparation of hyaline cartilage directly from skin, without generating iPS cells. PMID:21293062

A Synthetic Interaction Screen Identifies Factors Selectively Required for Proliferation and TERT Transcription in p53-Deficient Human Cancer Cells

PubMed Central

Park, Sung Mi; Zhu, Lihua J.; Debily, Marie-anne; Kittler, Ellen L. W.; Zapp, Maria L.; Lapointe, David; Gobeil, Stephane; Virbasius, Ching-Man; Green, Michael R.

2012-01-01

Numerous genetic and epigenetic alterations render cancer cells selectively dependent on specific genes and regulatory pathways, and represent potential vulnerabilities that can be therapeutically exploited. Here we describe an RNA interference (RNAi)–based synthetic interaction screen to identify genes preferentially required for proliferation of p53-deficient (p53−) human cancer cells. We find that compared to p53-competent (p53+) human cancer cell lines, diverse p53− human cancer cell lines are preferentially sensitive to loss of the transcription factor ETV1 and the DNA damage kinase ATR. In p53− cells, RNAi–mediated knockdown of ETV1 or ATR results in decreased expression of the telomerase catalytic subunit TERT leading to growth arrest, which can be reversed by ectopic TERT expression. Chromatin immunoprecipitation analysis reveals that ETV1 binds to a region downstream of the TERT transcriptional start-site in p53− but not p53+ cells. We find that the role of ATR is to phosphorylate and thereby stabilize ETV1. Our collective results identify a regulatory pathway involving ETV1, ATR, and TERT that is preferentially important for proliferation of diverse p53− cancer cells. PMID:23284306

Acromegaly and Cushing's syndrome associated with a foregut carcinoid tumor.

PubMed

Leveston, S A; McKeel, D W; Buckley, P J; Deschryver, K; Greider, M H; Jaffe, B M; Daughaday, W H

1981-10-01

We report an 18-yr-old youth with a metastatic foregut carcinoid tumor, Cushing's syndrome, and hypersomatotropic gigantism. Administration of cyproheptadine caused a dramatic fall in urinary cortisol excretion and plasma ACTH levels associated with clinical remission of the Cushing's syndrome. GH secretion was not affected by cyproheptadine administration. Ectopic ACTH secretion was confirmed by RIA of tumor extracts and immunohistochemical demonstration of ACTH-containing cells in hepatic metastases. There were two sources of GH production demonstrated in this patient. Ectopic secretion of GH by the carcinoid hepatic metastases was documented by both RIA and immunohistochemical techniques. A somatotrophic pituitary tumor was also present. The histological characteristics of this tumor suggest adenomatous hyperplasia rather than de novo neoplastic change as the likely mechanism of its pathogenesis. GH releasing factor-like activity was demonstrated in extracts of plasma and in extracts of the carcinoid tumor. We conclude that cyproheptadine exerted an effect on the ectopic ACTH-producing cells but not on the ectopic GH-producing cells or on adenohypophyseal GH secretion. Production of a GH releasing factor-like activity by the carcinoid tumor may have caused the pituitary somatotrophic tumor.

MicroRNA-218 inhibits the proliferation of human choriocarcinoma JEG-3 cell line by targeting Fbxw8

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

Shi, Dazun; Tan, Zhihui; Lu, Rong

2014-08-08

Highlights: • The miR-218 expression was decreased in choriocarcinoma cell lines. • The Fbxw8 protein expression was increased in choriocarcinoma cell lines. • We show that Fbxw8 is bona-fide target of miR-218 in JEG-3. • Ectopic miR-218 expression inhibits the proliferation of JEG-3 via Fbxw8. • Overexpression of miR-218 affected cyclin A and p27 expression via Fbxw8. - Abstract: MicroRNAs (miRNAs) are endogenous 19–25 nucleotide noncoding single-stranded RNAs that regulate gene expression by blocking the translation or decreasing the stability of mRNAs. In this study, we showed that miR-218 expression levels were decreased while Fbxw8 expression levels were increased inmore » human choriocarcinoma cell lines, and identified Fbxw8 as a novel direct target of miR-218. Overexpression of miR-218 inhibited cell growth arrest at G2/M phase, suppressed the protein levels of cyclin A and up-regulated the expression levels of p27 through decreasing the levels of Fbxw8. On the other hand, forced expression of Fbxw8 partly rescued the effect of miR-218 in the cells, attenuated cell proliferation decrease the percentage of cells at G2/M phase, induced cyclin A protein expression and suppressed the protein level of p27 through up-regulating the levels of Fbxw8. Taken together, these findings will shed light the role to mechanism of miR-218 in regulating JEG-3 cells proliferation via miR-218/Fbxw8 axis, and miR-218 may serve as a novel potential therapeutic target in human choriocarcinoma in the future.« less

Cytomorphology and sonographic features of ectopic thymic tissue diagnosed in paediatric FNA biopsies.

PubMed

Escobar, F A; Pantanowitz, L; Picarsic, J L; Craig, F E; Simons, J P; Viswanathan, P A; Yilmaz, S; Monaco, S E

2018-03-26

Ectopic thymic tissue can arise as an asymptomatic neck mass, which may be detected on imaging studies. The aim of this study was to determine the incidence of ectopic thymic tissue in paediatric FNAs and to the correlate clinical, radiological and cytomorphological findings. FNAs in children with neck and mediastinal lesions performed between January 2012 and July 2016 were reviewed for cases of ectopic thymus. These were then evaluated and correlated with the cytology findings. Of 739 FNAs, 13 (1.8%) cases from 11 patients showed ectopic thymic tissue. The targeted lesions were in the thyroid (n = 7), submandibular region (n = 1), superior mediastinum (n = 1) and paratracheal region (n = 1). The most common indication was for microcalcifications concerning for papillary thyroid carcinoma on ultrasound (n = 6). Imaging findings included fusiform lesions with linear and punctuate bright echoes. The cytology evaluation showed small lymphocytes with discohesive epithelioid cells in most cases, and proteinaceous fluid in the cystic case. There were rare macrophages and Hassall's corpuscles. Flow cytometry and/or immunostains were performed in all cases, supporting thymic origin. Ectopic thymic tissue is rarely present as a neck mass or thyroid nodule on FNA biopsy. The ultrasound imaging findings reveal a well-defined fusiform lesion with punctate bright echoes that could be misinterpreted as papillary thyroid carcinoma. The aspirates show a small lymphoid population, immunophenotypically compatible with thymic T-cells, in addition to scattered epithelial cells. Therefore, knowledge of the typical ultrasonographic and cytopathological features can help make a definitive diagnosis and avoid more invasive procedures in paediatric patients. © 2018 John Wiley & Sons Ltd.

Hsa-mir-145 is the top EWS-FLI1-repressed microRNA involved in a positive feedback loop in Ewing's sarcoma.

PubMed

Ban, J; Jug, G; Mestdagh, P; Schwentner, R; Kauer, M; Aryee, D N T; Schaefer, K-L; Nakatani, F; Scotlandi, K; Reiter, M; Strunk, D; Speleman, F; Vandesompele, J; Kovar, H

2011-05-05

EWS-FLI1 is a chromosome translocation-derived chimeric transcription factor that has a central and rate-limiting role in the pathogenesis of Ewing's sarcoma. Although the EWS-FLI1 transcriptomic signature has been extensively characterized on the mRNA level, information on its impact on non-coding RNA expression is lacking. We have performed a genome-wide analysis of microRNAs affected by RNAi-mediated silencing of EWS-FLI1 in Ewing's sarcoma cell lines, and differentially expressed between primary Ewing's sarcoma and mesenchymal progenitor cells. Here, we report on the identification of hsa-mir-145 as the top EWS-FLI1-repressed microRNA. Upon knockdown of EWS-FLI1, hsa-mir-145 expression dramatically increases in all Ewing's sarcoma cell lines tested. Vice versa, ectopic expression of the microRNA in Ewing's sarcoma cell lines strongly reduced EWS-FLI1 protein, whereas transfection of an anti-mir to hsa-mir-145 increased the EWS-FLI1 levels. Reporter gene assays revealed that this modulation of EWS-FLI1 protein was mediated by the microRNA targeting the FLI1 3'-untranslated region. Mutual regulations of EWS-FLI1 and hsa-mir-145 were mirrored by an inverse correlation between their expression levels in four of the Ewing's sarcoma cell lines tested. Consistent with the role of EWS-FLI1 in Ewing's sarcoma growth regulation, forced hsa-mir-145 expression halted Ewing's sarcoma cell line growth. These results identify feedback regulation between EWS-FLI1 and hsa-mir-145 as an important component of the EWS-FLI1-mediated Ewing's sarcomagenesis that may open a new avenue to future microRNA-mediated therapy of this devastating malignant disease.

Expression of the transcription factor Evi-1 in human erythroleukemia cell lines and in leukemias.

PubMed

Fontenay-Roupie, M; Bouscary, D; Melle, J; Viguié, F; Picard, F; Guesnu, M; Dreyfus, F

1997-02-01

The Evi-1 proto-oncogene is a zinc finger DNA binding protein. Although activation of the Evi-1 gene has been associated with chromosomal rearrangements of the 3q25-q28 region, ectopic expression of Evi-1 could also be observed in acute myelogenous leukemias and myelodysplastic syndromes without cytogenetic abnormalities of the 3q26 locus. In this study, human erythroleukemic cell lines were screened for the expression of Evi-1 mRNA by northern blotting. Evi-1 was expressed in all the erythroid cell lines, whether undifferentiated (K 562, HEL, LAMA 84) or exhibiting spontaneous terminal erythroid differentiation (KU 812, JK-1). Evi-1 mRNA levels were constant or elevated in hemoglobin-synthesizing KU 812 or K 562 cells in response to erythropoietin or hemin treatment, respectively. In human acute myeloblastic leukemias (AML), 11/30 expressed Evi-1 by RT-PCR. Among these cases, 4/6 erythroleukemias without abnormalities of the 3q25-q28 region were found positive. The presence of acidophilic erythroblasts (15-47% of bone marrow cells) accounted for the existence of a terminal erythroid differentiation in all Evi-1-positive AML M6, whereas one negative case was poorly differentiated and referred to as AML M6 variant. These results suggest that Evi-1 mRNA expression can coexist with erythroid differentiation.

Rac1 Dosage Is Crucial for Normal Endochondral Bone Growth.

PubMed

Suzuki, Dai; Bush, Jason R; Bryce, Dawn-Marie; Kamijo, Ryutaro; Beier, Frank

2017-10-01

Rac1, a member of the small Rho GTPase family, plays multiple cellular roles. Studies of mice conditionally lacking Rac1 have revealed essential roles for Rac1 in various tissues, including cartilage and limb mesenchyme, where Rac1 loss produces dwarfism and long bone shortening. To gain further insight into the role of Rac1 in skeletal development, we have used transgenic mouse lines to express a constitutively active (ca) Rac1 mutant protein in a Cre recombinase-dependent manner. Overexpression of caRac1 in limb bud mesenchyme or chondrocytes leads to reduced body weight and shorter bones compared with control mice. Histological analysis of growth plates showed that caRac1;Col2-Cre mice displayed ectopic hypertrophic chondrocytes in the proliferative zone and enlarged hypertrophic zones. These mice also displayed a reduced proportion of proliferating cell nuclear antigen-positive cells in the proliferative zone and nuclear β-catenin localization in the ectopic hypertrophic chondrocytes. Importantly, overexpression of caRac1 partially rescued the phenotypes of Rac1fl/fl;Col2-Cre and Rac1fl/fl;Prx1-Cre conditional knockout mice, including body weight, bone length, and growth plate disorganization. These results suggest that tight regulation of Rac1 activity is necessary for normal cartilage development. Copyright © 2017 Endocrine Society.

Nerve-independent and ectopically additional induction of taste buds in organ culture of fetal tongues.

PubMed

Honda, Kotaro; Tomooka, Yasuhiro

2016-10-01

An improved organ culture system allowed to observe morphogenesis of mouse lingual papillae and taste buds relatively for longer period, in which fetal tongues were analyzed for 6 d. Taste cells were defined as eosinophobic epithelial cells expressing CK8 and Sox2 within lingual epithelium. Addition of glycogen synthase kinase 3 beta inhibitor CHIR99021 induced many taste cells and buds in non-gustatory and gustatory stratified lingual epithelium. The present study clearly demonstrated induction of taste cells and buds ectopically and without innervation.

Induction of ectopic taste buds by SHH reveals the competency and plasticity of adult lingual epithelium

PubMed Central

Castillo, David; Seidel, Kerstin; Salcedo, Ernesto; Ahn, Christina; de Sauvage, Frederic J.; Klein, Ophir D.; Barlow, Linda A.

2014-01-01

Taste buds are assemblies of elongated epithelial cells, which are innervated by gustatory nerves that transmit taste information to the brain stem. Taste cells are continuously renewed throughout life via proliferation of epithelial progenitors, but the molecular regulation of this process remains unknown. During embryogenesis, sonic hedgehog (SHH) negatively regulates taste bud patterning, such that inhibition of SHH causes the formation of more and larger taste bud primordia, including in regions of the tongue normally devoid of taste buds. Here, using a Cre-lox system to drive constitutive expression of SHH, we identify the effects of SHH on the lingual epithelium of adult mice. We show that misexpression of SHH transforms lingual epithelial cell fate, such that daughter cells of lingual epithelial progenitors form cell type-replete, onion-shaped taste buds, rather than non-taste, pseudostratified epithelium. These SHH-induced ectopic taste buds are found in regions of the adult tongue previously thought incapable of generating taste organs. The ectopic buds are composed of all taste cell types, including support cells and detectors of sweet, bitter, umami, salt and sour, and recapitulate the molecular differentiation process of endogenous taste buds. In contrast to the well-established nerve dependence of endogenous taste buds, however, ectopic taste buds form independently of both gustatory and somatosensory innervation. As innervation is required for SHH expression by endogenous taste buds, our data suggest that SHH can replace the need for innervation to drive the entire program of taste bud differentiation. PMID:24993944

Hepatic Leukemia Factor Promotes Resistance To Cell Death: Implications For Therapeutics and Chronotherapy

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

Waters, Katrina M.; Sontag, Ryan L.; Weber, Thomas J.

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

Tyro3 Family-Mediated Cell Entry of Ebola and Marburg Viruses

PubMed Central

Shimojima, Masayuki; Takada, Ayato; Ebihara, Hideki; Neumann, Gabriele; Fujioka, Kouki; Irimura, Tatsuro; Jones, Steven; Feldmann, Heinz; Kawaoka, Yoshihiro

2006-01-01

Filoviruses, represented by the genera Ebolavirus and Marburgvirus, cause a lethal hemorrhagic fever in humans and in nonhuman primates. Although filovirus can replicate in various tissues or cell types in these animals, the molecular mechanisms of its broad tropism remain poorly understood. Here we show the involvement of members of the Tyro3 receptor tyrosine kinase family—Axl, Dtk, and Mer—in cell entry of filoviruses. Ectopic expression of these family members in lymphoid cells, which otherwise are highly resistant to filovirus infection, enhanced infection by pseudotype viruses carrying filovirus glycoproteins on their envelopes. This enhancement was reduced by antibodies to Tyro3 family members, Gas6 ligand, or soluble ectodomains of the members. Live Ebola viruses infected both Axl- and Dtk-expressing cells more efficiently than control cells. Antibody to Axl inhibited infection of pseudotype viruses in a number of Axl-positive cell lines. These results implicate each Tyro3 family member as a cell entry factor in filovirus infection. PMID:17005688

Functional analysis of Discoidin domain receptor 2 mutation and expression in squamous cell lung cancer.

PubMed

Kobayashi-Watanabe, Naomi; Sato, Akemi; Watanabe, Tatsuro; Abe, Tomonori; Nakashima, Chiho; Sueoka, Eisaburo; Kimura, Shinya; Sueoka-Aragane, Naoko

2017-08-01

Discoidin domain receptor (DDR) 2 mutations have recently been reported to be candidate targets of molecular therapy in lung squamous cell carcinoma (SQCC). However, the status of DDR2 expression and mutations, as well as their precise roles in lung SQCC, have not been clarified. We here report DDR2 mutation and expression status in clinical samples and its role of lung SQCC. We investigated DDR2 expression and mutation status in 44 human clinical samples and 7 cell lines. Biological functions of DDR2 were assessed by in vitro cell invasion assay and animal model experiments. Endogenous DDR2 protein expression levels were high in one cell line, PC-1, and immunohistochemistry of lung cancer tissue array showed high levels of DDR2 protein in 29% of lung SQCC patients. A mutation (T681I) identified in lung SQCC and the cell line EBC-1 was detected among 44 primary lung SQCC samples and 7 lung SQCC cell lines. Although Forced expression of DDR2 and its mutant (T681I) led to induce SQCC cell invasion in vitro, only wild type DDR2 enhanced lung metastasis in an animal model. We also found that ectopic expression of DDR2 induced MMP-1 mRNA expression accompanied by phosphorylation of c-Jun after treatment with its ligand, collagen type I, but DDR2 with the T681I mutation did not, suggesting that T681I mutation is an inactivating mutation. Overexpression of DDR2 might contribute to tumor progression in lung SQCC. The overexpression of DDR2 could be potential molecular target of lung SQCC. Copyright © 2017 Elsevier B.V. All rights reserved.

E2f1 mediates high glucose-induced neuronal death in cultured mouse retinal explants.

PubMed

Wang, Yujiao; Zhou, Yi; Xiao, Lirong; Zheng, Shijie; Yan, Naihong; Chen, Danian

2017-10-02

Diabetic retinopathy (DR) is the most common complication of diabetes and remains one of the major causes of blindness in the world; infants born to diabetic mothers have higher risk of developing retinopathy of prematurity (ROP). While hyperglycemia is a major risk factor, the molecular and cellular mechanisms underlying DR and diabetic ROP are poorly understood. To explore the consequences of retinal cells under high glucose, we cultured wild type or E2f1 -/- mouse retinal explants from postnatal day 8 with normal glucose, high osmotic or high glucose media. Explants were also incubated with cobalt chloride (CoCl 2 ) to mimic the hypoxic condition. We showed that, at 7 days post exposure to high glucose, retinal explants displayed elevated cell death, ectopic cell division and intact retinal vascular plexus. Cell death mainly occurred in excitatory neurons, such as ganglion and bipolar cells, which were also ectopically dividing. Many Müller glial cells reentered the cell cycle; some had irregular morphology or migrated to other layers. High glucose inhibited the hyperoxia-induced blood vessel regression of retinal explants. Moreover, inactivation of E2f1 rescued high glucose-induced ectopic division and cell death of retinal neurons, but not ectopic cell division of Müller glial cells and vascular phenotypes. This suggests that high glucose has direct but distinct effects on retinal neurons, glial cells and blood vessels, and that E2f1 mediates its effects on retinal neurons. These findings shed new light onto mechanisms of DR and the fetal retinal abnormalities associated with maternal diabetes, and suggest possible new therapeutic strategies.

RERG suppresses cell proliferation, migration and angiogenesis through ERK/NF-κB signaling pathway in nasopharyngeal carcinoma.

PubMed

Zhao, Weilin; Ma, Ning; Wang, Shumin; Mo, Yingxi; Zhang, Zhe; Huang, Guangwu; Midorikawa, Kaoru; Hiraku, Yusuke; Oikawa, Shinji; Murata, Mariko; Takeuchi, Kazuhiko

2017-06-28

Nasopharyngeal carcinoma (NPC) is a malignancy of the head and neck that is prevalent in Southeast Asia and southern China. Recent studies in epigenetics suggest that DNA methylation plays a pivotal role in the onset and progression of cancer. Combining the methyl-DNA binding domain capture technique and cDNA microarray analysis, we identified a unique hypermethylated gene, RERG (Ras-like estrogen-regulated growth inhibitor), that was down-regulated in NPC tissues. RERG is a tumor suppressor gene that was first reported in breast cancer. However, the functions of RERG are largely unknown in other tumor types. RERG expression was assessed in human subjects (NPC primary tissues and non-cancer tissues) and cell lines (NPC cell lines and an immortalized epithelial cell line NP460). Further, we investigated the methylation rate of RERG in both human subject and cell lines. 5-Aza-2'-deoxycytidine (Aza) or combined with trichostatin A (TSA) were treated to three NPC cell lines (HK1, C666-1 and HK1_EBV). In addition, the role of RERG in NPC cells and its underlying mechanisms were explored by overexpression of RERG in NPC cell lines. RERG was significantly down-regulated in NPC cancer nests compared to normal nasopharyngeal epithelium cells. Furthermore, the RERG promoter was frequently methylated in NPC tissues and cell lines. The RERG methylation rate yielded an area under the curve (AUC) of receiver operating characteristic (ROC) curve was 0.897 (95%CI: 0.818-0.976). The down-regulation of RERG was restored in NPC cells treated with Aza and TSA. In addition, ectopic expression of RERG in NPC cell lines resulted in a significant suppression of cell proliferation, clonogenicity, migration and invasion. RERG-overexpressing cells showed significantly slower growth and less angiogenesis in tumor xenografts in nude mice. RERG suppressed the ERK/NF-κB signaling pathway and inhibited tumor growth and angiogenesis with down-regulation of MMPs and IL8 in tumors of nude mouse xenografts. Our results suggest that RERG is frequently silenced by promoter CpG methylation in NPC, and acts as a functional tumor suppressor by suppressing the ERK/NF-κB signaling pathway. These findings support the potential use of RERG as a novel molecular target in NPC therapy.

CD22 regulates adaptive and innate immune responses of B cells.

PubMed

Kawasaki, Norihito; Rademacher, Christoph; Paulson, James C

2011-01-01

B cells sense microenvironments through the B cell receptor (BCR) and Toll-like receptors (TLRs). While signals from BCR and TLRs synergize to distinguish self from nonself, inappropriate regulation can result in development of autoimmune disease. Here we show that CD22, an inhibitory co-receptor of BCR, also negatively regulates TLR signaling in B cells. CD22-deficient (Cd22(-/-)) B cells exhibit hyperactivation in response to ligands of TLRs 3, 4 and 9. Evidence suggests that this results from impaired induction of suppressors of cytokine signaling 1 and 3, well-known suppressors of TLR signaling. Antibody-mediated sequestration of CD22 on wild-type (WT) B cells augments proliferation by TLR ligands. Conversely, expression of CD22 in a Cd22(-/-) B cell line blunts responses to TLR ligands. We also show that lipopolysaccharide-induced transcription by nuclear factor-κB is inhibited by ectopic expression of CD22 in a TLR4 reporter cell line. Taken together, these results suggest that negative regulation of TLR signaling is an intrinsic property of CD22. Since TLRs and BCR activate B cells through different signaling pathways, and are differentially localized in B cells, CD22 exhibits a broader regulation of receptors that mediate adaptive and innate immune responses of B cells than previously recognized. Copyright © 2010 S. Karger AG, Basel.

Ectopic prolactin secretion from a perivascular epithelioid cell tumor (PEComa).

PubMed

Korytnaya, Evgenia; Liu, Jiayan; Camelo-Piragua, Sandra; Sullivan, Stephen; Auchus, Richard J; Barkan, Ariel

2014-11-01

The diagnosis of ectopic pituitary hormone secretion requires abnormally high circulating hormone levels, absence of a pituitary tumor, and localization of the hormone in question to the extrapituitary malignant neoplasm. No case of a malignant solid tumor producing prolactin has been documented thus far. A 47-year-old woman presented with amenorrhea and galactorrhea of 3-year duration. Serum prolactin ranged from 300 to > 900 ng/mL, and other pituitary and thyroid indices were normal, including testing for macroprolactinemia. Pituitary magnetic resonance imaging revealed a partially empty sella but no tumor. Cabergoline 0.5 mg twice weekly did not affect her prolactinemia (1700 to 1900 ng/mL), and the medication was stopped. In the meantime, she developed abdominal pain, and a computed tomography scan showed a 17 × 13 × 8-cm mass abutting the distal stomach, proximal duodenum, and right colon. After the tumor was excised, her galactorrhea resolved, menstrual periodicity resumed within the first month, and serum prolactin fell to 5 ng/mL. Pathological examination of the excised tumor was consistent with perivascular epithelioid cell tumor. Between 5 and 10% of the tumor cells were strongly positive for prolactin on immunohistochemistry. RT-PCR detected prolactin mRNA in the tumor cell extract, confirming the diagnosis of ectopic prolactin synthesis and secretion. We present the first example of massive and symptomatic hyperprolactinemia due to ectopic prolactin production by a solid extrapituitary mesenchymal tumor confirmed with both mRNA analysis and immunohistochemistry. Ectopic prolactin secretion should be suspected in patients with a prolactin >200 ng/mL and negative sellar MRI.

Ectopic bone formation in nude rats using human osteoblasts seeded poly(3)hydroxybutyrate embroidery and hydroxyapatite-collagen tapes constructs.

PubMed

Mai, Ronald; Hagedorn, Manolo Gunnar; Gelinsky, Michael; Werner, Carsten; Turhani, Dritan; Späth, Heike; Gedrange, Tomas; Lauer, Günter

2006-09-01

The aim of this study was to evaluate the ectopic bone formation using tissue engineered cell-seeded constructs with two different scaffolds and primary human maxillary osteoblasts in nude rats over an implantation period of up to 96 days. Collagen I-coated Poly(3)hydroxybutyrate (PHB) embroidery and hydroxyapatite (HAP) collagen tapes were seeded with primary human maxillary osteoblasts (hOB) and implanted into athymic rnu/run rats. A total of 72 implants were placed into the back muscles of 18 rats. 24, 48 and 96 days after implantation, histological and histomorphometric analyses were made. The osteoblastic character of the cells was confirmed by immunocytochemistry and RT-PCR for osteocalcin. Histological analysis demonstrated that all cell-seeded constructs induced ectopic bone formation after 24, 48 and 96 days of implantation. There was more mineralized tissue in PHB constructs than in HAP-collagen tapes (at day 24; p < 0.05). Bone formation decreased with the increasing length of the implantation period. Osteocalcin expression verified the osteoblastic character of the cell-seeded constructs after implantation time. No bone formation and no osteocalcin expression were found in the control groups. Cell-seeded constructs either with PHB embroidery or HAP-collagen tapes can induce ectopic bone formation. However, the amount of bone formed decreased with increasing length of implantation.

New Advanced Technologies in Stem Cell Therapy

DTIC Science & Technology

2014-11-01

6-8 wks old utrophin/dystrophin double knockout (dKO) mice, a severe animal model of DMD, have an excess of ectopic fat , calcium deposits and...tissues in skeletal muscle alter the tissue environment and induce deregulation of muscle homeostasis; however, the cellular origin of muscle fat ...as a major contributor to ectopic fat cell, calcium deposits and fibrotic tissue formation within dystrophic muscle. In the current study, we propose

Hepatitis C virus utilizes VLDLR as a novel entry pathway.

PubMed

Ujino, Saneyuki; Nishitsuji, Hironori; Hishiki, Takayuki; Sugiyama, Kazuo; Takaku, Hiroshi; Shimotohno, Kunitada

2016-01-05

Various host factors are involved in the cellular entry of hepatitis C virus (HCV). In addition to the factors previously reported, we discovered that the very-low-density lipoprotein receptor (VLDLR) mediates HCV entry independent of CD81. Culturing Huh7.5 cells under hypoxic conditions significantly increased HCV entry as a result of the expression of VLDLR, which was not expressed under normoxic conditions in this cell line. Ectopic VLDLR expression conferred susceptibility to HCV entry of CD81-deficient Huh7.5 cells. Additionally, VLDLR-mediated HCV entry was not affected by the knockdown of cellular factors known to act as HCV receptors or HCV entry factors. Because VLDLR is expressed in primary human hepatocytes, our results suggest that VLDLR functions in vivo as an HCV receptor independent of canonical CD81-mediated HCV entry.

Aberrant expression of CKLF-like MARVEL transmembrane member 5 (CMTM5) by promoter methylation in myeloid leukemia.

PubMed

Niu, Jihong; Li, Henan; Zhang, Yao; Li, Jinlan; Xie, Min; Li, Lingdi; Qin, Xiaoying; Qin, Yazhen; Guo, Xiaohuan; Jiang, Qian; Liu, Yanrong; Chen, Shanshan; Huang, Xiaojun; Han, Wenling; Ruan, Guorui

2011-06-01

CMTM5 has been shown to exhibit tumor suppressor activities, however, its role in leukemia is unclear. Herein we firstly reported the expression and function of CMTM5 in myeloid leukemia. CMTM5 was down-regulated, or undetectable, in leukemia cell lines and bone marrow cells from leukemia patients with promoter methylation. Ectopic expression of CMTM5-v1 strongly inhibited the proliferation of K562 and MEG-01 cells. In addition, significant negative correlations were observed between CMTM5 and three leukemia-specific fusion genes (AML1-ETO, PML-RARα and BCR/ABL1). CMTM5 expression was up-regulated in patients who had undergone treatment. Therefore, CMTM5 may be involved in the pathomechanism of myeloid leukemias. Copyright © 2010 Elsevier Ltd. All rights reserved.

Overexpression of B-cell lymphoma 6 alters gene expression profile in a myeloma cell line and is associated with decreased DNA damage response.

PubMed

Tahara, Kenichi; Takizawa, Makiko; Yamane, Arito; Osaki, Yohei; Ishizaki, Takuma; Mitsui, Takeki; Yokohama, Akihiko; Saitoh, Takayuki; Tsukamoto, Norifumi; Matsumoto, Morio; Murakami, Hirokazu; Nojima, Yoshihisa; Handa, Hiroshi

2017-08-01

B-cell lymphoma 6 (BCL6) attenuates DNA damage response (DDR) through gene repression and facilitates tolerance to genomic instability during immunoglobulin affinity maturation in germinal center (GC) B cells. Although BCL6 expression is repressed through normal differentiation of GC B cells into plasma cells, a recent study showed the ectopic expression of BCL6 in primary multiple myeloma (MM) cells. However, the functional roles of BCL6 in MM cells are largely unknown. Here, we report that overexpression of BCL6 in a MM cell line, KMS12PE, induced transcriptional repression of ataxia telangiectasia mutated (ATM), a DDR signaling kinase, which was associated with a reduction in γH2AX formation after DNA damage. In contrast, transcription of known targets of BCL6 in GC B cells was not affected, suggesting a cell type-specific function of BCL6. To further investigate the effects of BCL6 overexpression on the MM cell line, we undertook mRNA sequence analysis and found an upregulation in the genomic mutator activation-induced cytidine deaminase (AID) with alteration in the gene expression profile, which is suggestive of de-differentiation from plasma cells. Moreover, interleukin-6 exposure to KMS12PE led to upregulation of BCL6 and AID, downregulation of ATM, and attenuation of DDR, which were consistent with the effects of BCL6 overexpression in this MM cell line. Taken together, these results indicated that overexpression of BCL6 alters gene expression profile and confers decreased DDR in MM cells. This phenotypic change could be reproduced by interleukin-6 stimulation, suggesting an important role of external stimuli in inducing genomic instability, which is a hallmark of MM cells. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

Epigenetically induced ectopic expression of UNCX impairs the proliferation and differentiation of myeloid cells

PubMed Central

Daniele, Giulia; Simonetti, Giorgia; Fusilli, Caterina; Iacobucci, Ilaria; Lonoce, Angelo; Palazzo, Antonio; Lomiento, Mariana; Mammoli, Fabiana; Marsano, Renè Massimiliano; Marasco, Elena; Mantovani, Vilma; Quentmeier, Hilmar; Drexler, Hans G; Ding, Jie; Palumbo, Orazio; Carella, Massimo; Nadarajah, Niroshan; Perricone, Margherita; Ottaviani, Emanuela; Baldazzi, Carmen; Testoni, Nicoletta; Papayannidis, Cristina; Ferrari, Sergio; Mazza, Tommaso; Martinelli, Giovanni; Storlazzi, Clelia Tiziana

2017-01-01

We here describe a leukemogenic role of the homeobox gene UNCX, activated by epigenetic modifications in acute myeloid leukemia (AML). We found the ectopic activation of UNCX in a leukemia patient harboring a t(7;10)(p22;p14) translocation, in 22 of 61 of additional cases [a total of 23 positive patients out of 62 (37.1%)], and in 6 of 75 (8%) of AML cell lines. UNCX is embedded within a low-methylation region (canyon) and encodes for a transcription factor involved in somitogenesis and neurogenesis, with specific expression in the eye, brain, and kidney. UNCX expression turned out to be associated, and significantly correlated, with DNA methylation increase at its canyon borders based on data in our patients and in archived data of patients from The Cancer Genome Atlas. UNCX-positive and -negative patients displayed significant differences in their gene expression profiles. An enrichment of genes involved in cell proliferation and differentiation, such as MAP2K1 and CCNA1, was revealed. Similar results were obtained in UNCX-transduced CD34+ cells, associated with low proliferation and differentiation arrest. Accordingly, we showed that UNCX expression characterizes leukemia cells at their early stage of differentiation, mainly M2 and M3 subtypes carrying wild-type NPM1. We also observed that UNCX expression significantly associates with an increased frequency of acute promyelocytic leukemia with PML-RARA and AML with t(8;21)(q22;q22.1); RUNX1-RUNX1T1 classes, according to the World Health Organization disease classification. In summary, our findings suggest a novel leukemogenic role of UNCX, associated with epigenetic modifications and with impaired cell proliferation and differentiation in AML. PMID:28411256

Epigenetically induced ectopic expression of UNCX impairs the proliferation and differentiation of myeloid cells.

PubMed

Daniele, Giulia; Simonetti, Giorgia; Fusilli, Caterina; Iacobucci, Ilaria; Lonoce, Angelo; Palazzo, Antonio; Lomiento, Mariana; Mammoli, Fabiana; Marsano, Renè Massimiliano; Marasco, Elena; Mantovani, Vilma; Quentmeier, Hilmar; Drexler, Hans G; Ding, Jie; Palumbo, Orazio; Carella, Massimo; Nadarajah, Niroshan; Perricone, Margherita; Ottaviani, Emanuela; Baldazzi, Carmen; Testoni, Nicoletta; Papayannidis, Cristina; Ferrari, Sergio; Mazza, Tommaso; Martinelli, Giovanni; Storlazzi, Clelia Tiziana

2017-07-01

We here describe a leukemogenic role of the homeobox gene UNCX , activated by epigenetic modifications in acute myeloid leukemia (AML). We found the ectopic activation of UNCX in a leukemia patient harboring a t(7;10)(p22;p14) translocation, in 22 of 61 of additional cases [a total of 23 positive patients out of 62 (37.1%)], and in 6 of 75 (8%) of AML cell lines. UNCX is embedded within a low-methylation region (canyon) and encodes for a transcription factor involved in somitogenesis and neurogenesis, with specific expression in the eye, brain, and kidney. UNCX expression turned out to be associated, and significantly correlated, with DNA methylation increase at its canyon borders based on data in our patients and in archived data of patients from The Cancer Genome Atlas. UNCX -positive and -negative patients displayed significant differences in their gene expression profiles. An enrichment of genes involved in cell proliferation and differentiation, such as MAP2K1 and CCNA1 , was revealed. Similar results were obtained in UNCX -transduced CD34 + cells, associated with low proliferation and differentiation arrest. Accordingly, we showed that UNCX expression characterizes leukemia cells at their early stage of differentiation, mainly M2 and M3 subtypes carrying wild-type NPM1 We also observed that UNCX expression significantly associates with an increased frequency of acute promyelocytic leukemia with PML-RARA and AML with t(8;21)(q22;q22.1); RUNX1-RUNX1T1 classes, according to the World Health Organization disease classification. In summary, our findings suggest a novel leukemogenic role of UNCX , associated with epigenetic modifications and with impaired cell proliferation and differentiation in AML. Copyright© 2017 Ferrata Storti Foundation.

Sex-specific silencing of X-linked genes by Xist RNA

PubMed Central

Gayen, Srimonta; Maclary, Emily; Hinten, Michael; Kalantry, Sundeep

2016-01-01

X-inactive specific transcript (Xist) long noncoding RNA (lncRNA) is thought to catalyze silencing of X-linked genes in cis during X-chromosome inactivation, which equalizes X-linked gene dosage between male and female mammals. To test the impact of Xist RNA on X-linked gene silencing, we ectopically induced endogenous Xist by ablating the antisense repressor Tsix in mice. We find that ectopic Xist RNA induction and subsequent X-linked gene silencing is sex specific in embryos and in differentiating embryonic stem cells (ESCs) and epiblast stem cells (EpiSCs). A higher frequency of XΔTsixY male cells displayed ectopic Xist RNA coating compared with XΔTsixX female cells. This increase reflected the inability of XΔTsixY cells to efficiently silence X-linked genes compared with XΔTsixX cells, despite equivalent Xist RNA induction and coating. Silencing of genes on both Xs resulted in significantly reduced proliferation and increased cell death in XΔTsixX female cells relative to XΔTsixY male cells. Thus, whereas Xist RNA can inactivate the X chromosome in females it may not do so in males. We further found comparable silencing in differentiating XΔTsixY and 39,XΔTsix (XΔTsixO) ESCs, excluding the Y chromosome and instead implicating the X-chromosome dose as the source of the sex-specific differences. Because XΔTsixX female embryonic epiblast cells and EpiSCs harbor an inactivated X chromosome prior to ectopic inactivation of the active XΔTsix X chromosome, we propose that the increased expression of one or more X-inactivation escapees activates Xist and, separately, helps trigger X-linked gene silencing. PMID:26739568

RUNX2 correlates with subtype-specific breast cancer in a human tissue microarray, and ectopic expression of Runx2 perturbs differentiation in the mouse mammary gland

PubMed Central

McDonald, Laura; Ferrari, Nicola; Terry, Anne; Bell, Margaret; Mohammed, Zahra M.; Orange, Clare; Jenkins, Alma; Muller, William J.; Gusterson, Barry A.; Neil, James C.; Edwards, Joanne; Morris, Joanna S.; Cameron, Ewan R.; Blyth, Karen

2014-01-01

RUNX2, a master regulator of osteogenesis, is oncogenic in the lymphoid lineage; however, little is known about its role in epithelial cancers. Upregulation of RUNX2 in cell lines correlates with increased invasiveness and the capacity to form osteolytic disease in models of breast and prostate cancer. However, most studies have analysed the effects of this gene in a limited number of cell lines and its role in primary breast cancer has not been resolved. Using a human tumour tissue microarray, we show that high RUNX2 expression is significantly associated with oestrogen receptor (ER)/progesterone receptor (PR)/HER2-negative breast cancers and that patients with high RUNX2 expression have a poorer survival rate than those with negative or low expression. We confirm RUNX2 as a gene that has a potentially important functional role in triple-negative breast cancer. To investigate the role of this gene in breast cancer, we made a transgenic model in which Runx2 is specifically expressed in murine mammary epithelium under the control of the mouse mammary tumour virus (MMTV) promoter. We show that ectopic Runx2 perturbs normal development in pubertal and lactating animals, delaying ductal elongation and inhibiting lobular alveolar differentiation. We also show that the Runx2 transgene elicits age-related, pre-neoplastic changes in the mammary epithelium of older transgenic animals, suggesting that elevated RUNX2 expression renders such tissue more susceptible to oncogenic changes and providing further evidence that this gene might have an important, context-dependent role in breast cancer. PMID:24626992

Aquaporin 5 Plays a Role in Estrogen-Induced Ectopic Implantation of Endometrial Stromal Cells in Endometriosis

PubMed Central

Jiang, Xiu Xiu; Fei, Xiang Wei; Zhao, Li; Ye, Xiao Lei; Xin, Liao Bin; Qu, Yang; Xu, Kai Hong; Wu, Rui Jin; Lin, Jun

2015-01-01

Aquaporin 5 (AQP5) participates in the migration of endometrial cells. Elucidation of the molecular mechanisms associated with AQP5-mediated, migration of endometrial cells may contribute to a better understanding of endometriosis. Our objectives included identifying the estrogen-response element (ERE) in the promoter region of the AQP5 gene, and, investigating the effects of AQP5 on ectopic implantation of endometrial cells. Luciferase reporter assays and electrophoretic mobility shift assay (EMSA) identified the ERE-like motif in the promoter region of the AQP5 gene. After blocking and up-regulating estradiol (E2) levels, we analysed the expression of AQP5 in endometrial stromal (ES) cells. After blocking E2 /or phosphatidylinositol 3 kinase(PI3K), we analysed the role of AQP5 in signaling pathways. We constructed an AQP5, shRNA, lentiviral vector to knock out the AQP5 gene in ES cells. After knock-out of the AQP5 gene, we studied the role of AQP5 in cell invasion, proliferation, and the formation of ectopic endometrial implants in female mice. We identified an estrogen-response element in the promoter region of the AQP5 gene. Estradiol (E2) increased AQP5 expression in a dose-dependent fashion, that was blocked by ICI182,780(an estrogen receptor inhibitor). E2 activated PI3K /protein kinase B(AKT) pathway (PI3K/AKT), that, in turn, increased AQP5 expression. LY294002(PI3K inhibitor) attenuated estrogen-enhanced, AQP5 expression. Knock-out of the AQP5 gene with AQP5 shRNA lentiviral vector significantly inhibited E2-enhanced invasion, proliferation of ES cells and formation of ectopic implants. Estrogen induces AQP5 expression by activating ERE in the promoter region of the AQP5gene, activates the PI3K/AKT pathway, and, promotes endometrial cell invasion and proliferation. These results provide new insights into some of the mechanisms that may underpin the development of deposits of ectopic endometrium. PMID:26679484

Mutations in CIC and IDH1 cooperatively regulate 2-hydroxyglutarate levels and cell clonogenicity

PubMed Central

Chittaranjan, Suganthi; Chan, Susanna; Yang, Cindy; Yang, Kevin C.; Chen, Vincent; Moradian, Annie; Firme, Marlo; Song, Jungeun; Go, Nancy E.; Blough, Michael D.; Chan, Jennifer A.; Cairncross, J. Gregory; Gorski, Sharon M.; Morin, Gregg B.; Yip, Stephen; Marra, Marco A.

2014-01-01

The majority of oligodendrogliomas (ODGs) exhibit combined losses of chromosomes 1p and 19q and mutations of isocitrate dehydrogenase (IDH1-R132H or IDH2-R172K). Approximately 70% of ODGs with 1p19q co-deletions harbor somatic mutations in the Capicua Transcriptional Repressor (CIC) gene on chromosome 19q13.2. Here we show that endogenous long (CIC-L) and short (CIC-S) CIC proteins are predominantly localized to the nucleus or cytoplasm, respectively. Cytoplasmic CIC-S is found in close proximity to the mitochondria. To study wild type and mutant CIC function and motivated by the paucity of 1p19q co-deleted ODG lines, we created HEK293 and HOG stable cell lines ectopically co-expressing CIC and IDH1. Non-mutant lines displayed increased clonogenicity, but cells co-expressing the mutant IDH1-R132H with either CIC-S-R201W or -R1515H showed reduced clonogenicity in an additive manner, demonstrating cooperative effects in our assays. Expression of mutant CIC-R1515H increased cellular 2-Hydroxyglutarate (2HG) levels compared to wild type CIC in IDH1-R132H background. Levels of phosphorylated ATP-citrate Lyase (ACLY) were lower in cell lines expressing mutant CIC-S proteins compared to cells expressing wild type CIC-S, supporting a cytosolic citrate metabolism-related mechanism of reduced clonogenicity in our in vitro model systems. ACLY or phospho-ACLY were similarly reduced in CIC-mutant 1p19q co-deleted oligodendroglioma patient samples. PMID:25277207

The ectopic expression of a pectin methyl esterase inhibitor increases pectin methyl esterification and limits fungal diseases in wheat.

PubMed

Volpi, Chiara; Janni, Michela; Lionetti, Vincenzo; Bellincampi, Daniela; Favaron, Francesco; D'Ovidio, Renato

2011-09-01

Cell wall pectin methyl esterification can influence plant resistance because highly methyl-esterified pectin can be less susceptible to the hydrolysis by pectic enzymes such as fungal endopolygalacturonases (PG). Pectin is secreted into the cell wall in a highly methyl-esterified form and, here, is de-methyl esterified by pectin methyl esterase (PME). The activity of PME is controlled by specific protein inhibitors called PMEI; consequently, an increased inhibition of PME by PMEI might modify the pectin methyl esterification. In order to test the possibility of improving wheat resistance by modifying the methyl esterification of pectin cell wall, we have produced durum wheat transgenic lines expressing the PMEI from Actinidia chinensis (AcPMEI). The expression of AcPMEI endows wheat with a reduced endogenous PME activity, and transgenic lines expressing a high level of the inhibitor showed a significant increase in the degree of methyl esterification. These lines showed a significant reduction of disease symptoms caused by the fungal pathogens Bipolaris sorokiniana or Fusarium graminearum. This increased resistance was related to the impaired ability of these fungal pathogens to grow on methyl-esterified pectin and to a reduced activity of the fungal PG to hydrolyze methyl-esterified pectin. In addition to their importance for wheat improvement, these results highlight the primary role of pectin despite its low content in the wheat cell wall.

Failure of in vitro-differentiated mesenchymal stem cells from the synovial membrane to form ectopic stable cartilage in vivo.

PubMed

De Bari, Cosimo; Dell'Accio, Francesco; Luyten, Frank P

2004-01-01

We previously reported the identification in a nude mouse assay of molecular markers predictive of the capacity of articular cartilage-derived cells (ACDCs) to form ectopic stable cartilage that is resistant to vascular invasion and endochondral ossification. In the present study, we investigated whether in vitro-differentiated mesenchymal stem cells (MSCs) from the synovial membrane (SM) express the stable-chondrocyte markers and form ectopic stable cartilage in vivo. Chondrogenesis was induced in micromass culture with the addition of transforming growth factor beta1 (TGFbeta1). After acquisition of the cartilage phenotype, micromasses were implanted subcutaneously into nude mice. Alternatively, cells were released enzymatically and either replated in monolayer or injected intramuscularly into nude mice. Marker analysis was performed by quantitative reverse transcription-polymerase chain reaction. Cell death was detected with TUNEL assay. Cartilage-like micromasses and released cells expressed the stable-chondrocyte markers at levels comparable with those expressed by stable ACDCs. The released cells lost chondrocyte marker expression by 24 hours in monolayer and failed to form cartilage when injected intramuscularly into nude mice. Instead, myogenic differentiation was detected. When intact TGFbeta1-treated micromasses were implanted subcutaneously, they partially lost their cartilage phenotype and underwent cell death and neoangiogenesis within 1 week. At later time points (15-40 days), we retrieved neither cartilage nor bone, and human cells were not detectable. The chondrocyte-like phenotype of human SM MSCs, induced in vitro under specific conditions, appears to be unstable and is not sufficient to obtain ectopic formation of stable cartilage in vivo. Studies in animal models of joint surface defect repair are necessary to evaluate the stability of the SM MSC chondrocyte-like phenotype within the joint environment.

Serum β-hCG levels post-treatment of ectopic pregnancy with a single dose of intramuscular methotrexate.

PubMed

Hadinata, Ignatius E; Doyle, Lex W; Thompson, Derrick; Reti, Leslie

2015-04-01

The cytotoxic management of ectopic pregnancy using a single dose of intramuscular methotrexate injection has been well established as effective for a select number of women with unruptured tubal ectopic pregnancy where there are minimal symptoms. The purpose of this study was to create centile curves of serum β-hCG levels following successful treatment with a single dose of 50 mg/m(2) of intramuscular methotrexate to treat ectopic pregnancy. Data were retrieved from women treated at the Royal Women's Hospital for ectopic pregnancy between 2006 and 2012. Only women with minimal symptoms, initial serum β-hCG ≤5000 IU/L and ectopic mass size of ≤35 mm on ultrasound were included. Two hundred and fifty-three cases of ectopic pregnancy were analysed. Initial β-hCG of women in the study ranged from 18 to 3995 IU/L with a median of 497 (25th to 75th centiles; 222-1160) IU/L. The median levels of β-hCG levels at day 4, 7 and 14 postmethotrexate injection were 73.8, 47.2 and 10.4% of the initial β-hCG level, respectively. The 90th centiles of β-hCG levels at day 4, 7 and 14 were 124.7, 93.8 and 40.0% of initial β-hCG level, respectively. Whilst no comparison with those unsuccessfully treated was made, pending further validation studies, the use of these curves may reduce the reliance on specialist units and streamline care for many women with ectopic pregnancy, such as those whose β-hCG regress in line with centile values without crossing a certain threshold. © 2015 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

Induction of ectopic taste buds by SHH reveals the competency and plasticity of adult lingual epithelium.

PubMed

Castillo, David; Seidel, Kerstin; Salcedo, Ernesto; Ahn, Christina; de Sauvage, Frederic J; Klein, Ophir D; Barlow, Linda A

2014-08-01

Taste buds are assemblies of elongated epithelial cells, which are innervated by gustatory nerves that transmit taste information to the brain stem. Taste cells are continuously renewed throughout life via proliferation of epithelial progenitors, but the molecular regulation of this process remains unknown. During embryogenesis, sonic hedgehog (SHH) negatively regulates taste bud patterning, such that inhibition of SHH causes the formation of more and larger taste bud primordia, including in regions of the tongue normally devoid of taste buds. Here, using a Cre-lox system to drive constitutive expression of SHH, we identify the effects of SHH on the lingual epithelium of adult mice. We show that misexpression of SHH transforms lingual epithelial cell fate, such that daughter cells of lingual epithelial progenitors form cell type-replete, onion-shaped taste buds, rather than non-taste, pseudostratified epithelium. These SHH-induced ectopic taste buds are found in regions of the adult tongue previously thought incapable of generating taste organs. The ectopic buds are composed of all taste cell types, including support cells and detectors of sweet, bitter, umami, salt and sour, and recapitulate the molecular differentiation process of endogenous taste buds. In contrast to the well-established nerve dependence of endogenous taste buds, however, ectopic taste buds form independently of both gustatory and somatosensory innervation. As innervation is required for SHH expression by endogenous taste buds, our data suggest that SHH can replace the need for innervation to drive the entire program of taste bud differentiation. © 2014. Published by The Company of Biologists Ltd.

Interleukin-4 induces expression of eotaxin in endometriotic stromal cells.

PubMed

Ouyang, Zhuo; Osuga, Yutaka; Hirota, Yasushi; Hirata, Tetsuya; Yoshino, Osamu; Koga, Kaori; Yano, Tetsu; Taketani, Yuji

2010-06-01

To study the relationship between eotaxin and interleukin-4 (IL-4) in the pathophysiology of endometriosis. Comparative and laboratory study. University teaching hospital reproductive endocrinology and infertility practice. Ectopic endometrial tissues were collected from women with endometriosis. Ectopic endometrial stromal cells (ESCs) were isolated and cultured with IL-4. Ectopic endometriotic tissues were immunostained for eotaxin and IL-4. Gene expression of eotaxin was determined by standard and real-time reverse-transcriptase polymerase chain reaction. Secretion of eotaxin from ESC was measured using specific ELISA. The immunostained sections were examined. Interleukin-4 (IL-4) increased mRNA expression and protein secretion of eotaxin from ESC in a dose-dependent manner. Immunohistochemical analysis showed that eotaxin-positive cells colocalized with IL-4-positive cells and accumulated around the blood vessels in the stroma of endometriotic tissue. IL-4 induces eotaxin in ESCs, which might promote angiogenesis and the subsequent development of endometriosis. Copyright (c) 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

STAT, Wingless, and Nurf-38 determine the accuracy of regeneration after radiation damage in Drosophila.

PubMed

Verghese, Shilpi; Su, Tin Tin

2017-10-01

We report here a study of regeneration in Drosophila larval wing imaginal discs after damage by ionizing radiation. We detected faithful regeneration that restored a wing disc and abnormal regeneration that produced an extra wing disc. We describe a sequence of changes in cell number, location and fate that occur to produce an ectopic disc. We identified a group of cells that not only participate in ectopic disc formation but also recruit others to do so. STAT92E (Drosophila STAT3/5) and Nurf-38, which encodes a member of the Nucleosome Remodeling Factor complex, oppose each other in these cells to modulate the frequency of ectopic disc growth. The picture that emerges is one in which activities like STAT increase after radiation damage and fulfill essential roles in rebuilding the tissue. But such activities must be kept in check so that one and only one wing disc is regenerated.

SOX2 plays a critical role in EGFR-mediated self-renewal of human prostate cancer stem-like cells.

PubMed

Rybak, Adrian P; Tang, Damu

2013-12-01

SOX2 is an essential transcription factor for stem cells and plays a role in tumorigenesis, however its role in prostate cancer stem cells (PCSCs) remains unclear. We report here a significant upregulation of SOX2 at both mRNA and protein levels in DU145 PCSCs propagated as suspension spheres in vitro. The expression of SOX2 in DU145 PCSCs is positively regulated by epidermal growth factor receptor (EGFR) signaling. Activation of EGFR signaling, following the addition of epidermal growth factor (EGF) or ectopic expression of a constitutively-active EGFR mutant (EGFRvIII), increased SOX2 expression and the self-renewal of DU145 PCSCs. Conversely, a small molecule EGFR inhibitor (AG1478) blocked EGFR activation, reduced SOX2 expression and inhibited PCSC self-renewal activity, implicating SOX2 in mediating EGFR-dependent self-renewal of PCSCs. In line with this notion, ectopic SOX2 expression enhanced EGF-induced self-renewal of DU145 PCSCs, while SOX2 knockdown reduced PCSC self-renewal with EGF treatment no longer capable of enhancing their propagation. Furthermore, SOX2 knockdown reduced the capacity of DU145 PCSCs to grow under anchorage-independent conditions. Finally, DU145 PCSCs generated xenograft tumors more aggressively with elevated levels of SOX2 expression compared to xenograft tumors derived from non-PCSCs. Collectively, we provide evidence that SOX2 plays a critical role in EGFR-mediated self-renewal of DU145 PCSCs. © 2013.

NF-kB and c-Jun induce the expression of the oncogenic miR-221 and miR-222 in prostate carcinoma and glioblastoma cells

PubMed Central

Galardi, Silvia; Mercatelli, Neri; Farace, Maria G.; Ciafrè, Silvia A.

2011-01-01

MicroRNAs (miRNAs) are potent negative regulators of gene expression involved in all aspects of cell biology. They finely modulate virtually all physiological pathways in metazoans, and are deeply implicated in all main pathologies, among which cancer. Mir-221 and miR-222, two closely related miRNAs encoded in cluster from a genomic region on chromosome X, are strongly upregulated in several forms of human tumours. In this work, we report that the ectopic modulation of NF-kB modifies miR-221/222 expression in prostate carcinoma and glioblastoma cell lines, where we had previously shown their oncogenic activity. We identify two separate distal regions upstream of miR-221/222 promoter which are bound by the NF-kB subunit p65 and drive efficient transcription in luciferase reporter assays; consistently, the site-directed mutagenesis disrupting p65 binding sites or the ectopical inhibition of NF-kB activity significantly reduce luciferase activity. In the most distal enhancer region, we also define a binding site for c-Jun, and we show that the binding of this factor cooperates with that of p65, fully accounting for the observed upregulation of miR-221/222. Thus our work uncovers an additional mechanism through which NF-kB and c-Jun, two transcription factors deeply involved in cancer onset and progression, contribute to oncogenesis, by inducing miR-221/222 transcription. PMID:21245048

MicroRNA 421 suppresses DPC4/Smad4 in pancreatic cancer

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

Hao, Jun; Zhang, Shuyu; Zhou, Yingqi

2011-03-25

Research highlights: {yields} We identify miR-421 as a novel potential regulator of DPC4/Smad4. {yields} The expression levels of miR-421 and DPC4/Smad4 are inversely correlated in human clinical specimens of pancreatic cancer. {yields} Overexpression of miR-421 represses the reporter activities driven by the 3'-UTR of DPC4/Smad4 and DPC4/Smad4 protein level in pancreatic cancer cell. {yields} Ectopic expression of miR-421 promotes the proliferation and colony formation of pancreatic cancer cell. -- Abstract: MicroRNAs (miRNAs) have emerged as important regulators in the development of pancreatic cancer and may be a valuable therapeutic application. DPC4/Smad4 is a critical tumor suppressor involved in the progressionmore » of pancreatic cancer, but few studies have been conducted to determine its relationship with miRNAs. In this study, we identify miR-421 as a potential regulator of DPC4/Smad4. We find that in human clinical specimens of pancreatic cancer miR-421 is aberrantly upregulated while DPC4/Smad4 is strongly repressed, and their levels of expression are inversely correlated. Moreover, ectopic expression of miR-421 significantly decreases DPC4/Smad4 protein level in pancreatic cancer cell lines and simultaneously promotes cell proliferation and colony formation in vitro. Our findings identify miR-421 as a potent regulator of DPC4/Smad4, which may provide a novel therapeutic strategy for treatment of DPC4/Smad4-driven pancreatic cancer.« less

Reactive oxygen species spermine metabolites generated from amine oxidases and radiation represent a therapeutic gain in cancer treatments.

PubMed

Amendola, Roberto; Cervelli, Manuela; Fratini, Emiliano; Sallustio, Davide E; Tempera, Giampiero; Ueshima, Taichi; Mariottini, Paolo; Agostinelli, Enzo

2013-09-01

The most frequent interventions in cancer therapy are currently the destruction of cells by irradiation or administration of drugs both able to induce radical formation and toxic metabolites by enzyme-catalyzed reactions. The aim of this study was to determine the cell viability of cells undergoing a DNA damage threshold accomplished by ROS overproduction via both ectopic expression of murine spermine oxidase (mSMOX) and bovine serum amine oxidase (BSAO) enzymes. Low dose of X-irradiation delivers a challenging dose of damage as evaluated in proficient Chinese hamster AA8 cell line and both deficient transcription-coupled nucleotide excision repair (NER) UV61 cells and deficient base excision repair (BER) EM9 cells, at 6 and 24 h after exposure. The priming dose of ROS overexposure by mSMOX provokes an adaptive response in N18TG2, AA8 and EM9 cell lines at 24 h. Interestingly, in the UV61 cells, ROS overexposure by mSMOX delivers an earlier adaptive response to radiation. The enzymatic formation of toxic metabolites has mainly been investigated on wild-type (WT) and multidrug-resistant (MDR) cancer cell lines, using and spermine as substrate of the BSAO enzyme. MDR cells are more sensitive to the toxic polyamine metabolites than WT cells, thus indicating a new therapeutic strategy to overcome MDR tumors. Since SMOX in mammals is differentially activated in a tissue-specific manner and cancer cells can differ in terms of DNA repair and MDR capabilities, it could be of interest to simultaneously treat with very low dose of X-rays and/or to alter SMOX metabolism to generate a differential response in healthy and cancer tissues.

Ectopic lignification in the flax lignified bast fiber1 mutant stem is associated with tissue-specific modifications in gene expression and cell wall composition.

PubMed

Chantreau, Maxime; Portelette, Antoine; Dauwe, Rebecca; Kiyoto, Shingo; Crônier, David; Morreel, Kris; Arribat, Sandrine; Neutelings, Godfrey; Chabi, Malika; Boerjan, Wout; Yoshinaga, Arata; Mesnard, François; Grec, Sebastien; Chabbert, Brigitte; Hawkins, Simon

2014-11-01

Histochemical screening of a flax ethyl methanesulfonate population led to the identification of 93 independent M2 mutant families showing ectopic lignification in the secondary cell wall of stem bast fibers. We named this core collection the Linum usitatissimum (flax) lbf mutants for lignified bast fibers and believe that this population represents a novel biological resource for investigating how bast fiber plants regulate lignin biosynthesis. As a proof of concept, we characterized the lbf1 mutant and showed that the lignin content increased by 350% in outer stem tissues containing bast fibers but was unchanged in inner stem tissues containing xylem. Chemical and NMR analyses indicated that bast fiber ectopic lignin was highly condensed and rich in G-units. Liquid chromatography-mass spectrometry profiling showed large modifications in the oligolignol pool of lbf1 inner- and outer-stem tissues that could be related to ectopic lignification. Immunological and chemical analyses revealed that lbf1 mutants also showed changes to other cell wall polymers. Whole-genome transcriptomics suggested that ectopic lignification of flax bast fibers could be caused by increased transcript accumulation of (1) the cinnamoyl-CoA reductase, cinnamyl alcohol dehydrogenase, and caffeic acid O-methyltransferase monolignol biosynthesis genes, (2) several lignin-associated peroxidase genes, and (3) genes coding for respiratory burst oxidase homolog NADPH-oxidases necessary to increase H2O2 supply. © 2014 American Society of Plant Biologists. All rights reserved.

Ectopic Lignification in the Flax lignified bast fiber1 Mutant Stem Is Associated with Tissue-Specific Modifications in Gene Expression and Cell Wall Composition[C][W

PubMed Central

Chantreau, Maxime; Portelette, Antoine; Dauwe, Rebecca; Kiyoto, Shingo; Crônier, David; Morreel, Kris; Arribat, Sandrine; Neutelings, Godfrey; Chabi, Malika; Boerjan, Wout; Yoshinaga, Arata; Mesnard, François; Grec, Sebastien; Chabbert, Brigitte; Hawkins, Simon

2014-01-01

Histochemical screening of a flax ethyl methanesulfonate population led to the identification of 93 independent M2 mutant families showing ectopic lignification in the secondary cell wall of stem bast fibers. We named this core collection the Linum usitatissimum (flax) lbf mutants for lignified bast fibers and believe that this population represents a novel biological resource for investigating how bast fiber plants regulate lignin biosynthesis. As a proof of concept, we characterized the lbf1 mutant and showed that the lignin content increased by 350% in outer stem tissues containing bast fibers but was unchanged in inner stem tissues containing xylem. Chemical and NMR analyses indicated that bast fiber ectopic lignin was highly condensed and rich in G-units. Liquid chromatography-mass spectrometry profiling showed large modifications in the oligolignol pool of lbf1 inner- and outer-stem tissues that could be related to ectopic lignification. Immunological and chemical analyses revealed that lbf1 mutants also showed changes to other cell wall polymers. Whole-genome transcriptomics suggested that ectopic lignification of flax bast fibers could be caused by increased transcript accumulation of (1) the cinnamoyl-CoA reductase, cinnamyl alcohol dehydrogenase, and caffeic acid O-methyltransferase monolignol biosynthesis genes, (2) several lignin-associated peroxidase genes, and (3) genes coding for respiratory burst oxidase homolog NADPH-oxidases necessary to increase H2O2 supply. PMID:25381351

Germ-line induction of the Caenorhabditis elegans vulva

PubMed Central

Thompson, Beth E.; Lamont, Liana B.; Kimble, Judith

2006-01-01

Development of the Caenorhabditis elegans vulva serves as a paradigm for intercellular signaling during animal development. In wild-type animals, the somatic gonadal anchor cell generates the LIN-3/EGF ligand to induce vulval fates in the underlying hypodermis, whereas FBF, FOG-1, and FOG-3 control germ-line development. Here we report that FBF functions redundantly with FOG-1 and FOG-3 to control vulval induction: animals lacking FBF and either FOG-1 or FOG-3 have multiple vulvae, the Muv phenotype. The fog; fbf Muv phenotype is generated by aberrant induction of vulval precursor cells (VPCs): in wild-type animals, three VPCs are induced to form a single vulva, but, in fog; fbf mutants, four or five VPCs are typically induced, resulting in ectopic vulvae. Laser ablation experiments and mosaic analyses demonstrate that the germ line is critical for the fog; fbf Muv phenotype. Consistent with that site of action, we detect FBF and FOG-1 in the germ line but not in the VPCs. The simplest interpretation is that FOG-1, FOG-3, and FBF act in the germ line to influence vulval fates. The LIN-3/EGF ligand may be the germ-line signal to the VPCs: the fog; fbf Muv phenotype depends on LIN-3 activity, and the lin-3 3′ UTR possesses an FBF binding element. Our findings reveal new insights into germ line-to-soma signals and the role of PUF proteins in animal development. PMID:16407099

Aberrant, ectopic expression of VEGF and VEGF receptors 1 and 2 in malignant colonic epithelial cells. Implications for these cells growth via an autocrine mechanism

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

Ahluwalia, Amrita; Jones, Michael K.; Department of Medicine, University of California, Irvine, CA

2013-08-09

Highlights: •Malignant colonic epithelial cells express VEGF and its receptors. •Cultured colon cancer cells secrete VEGF into the medium. •Inhibition of VEGF receptor significantly decreases colon cancer cell proliferation. •VEGF is critical for colon cancer cell growth. -- Abstract: Vascular endothelial growth factor A (referred to as VEGF) is implicated in colon cancer growth. Currently, the main accepted mechanism by which VEGF promotes colon cancer growth is via the stimulation of angiogenesis, which was originally postulated by late Judah Folkman. However, the cellular source of VEGF in colon cancer tissue; and, the expression of VEGF and its receptors VEGF-R1 andmore » VEGF-R2 in colon cancer cells are not fully known and are subjects of controversy. Material and methods: We examined and quantified expression of VEGF, VEGF-R1 and VEGF-R2 in three different human colonic tissue arrays containing sections of adenocarcinoma (n = 43) and normal mucosa (n = 41). In human colon cancer cell lines HCT116 and HT29 and normal colon cell lines NCM356 and NCM460, we examined expression of VEGF, VEGF-R1 and VEGF-R2 mRNA and protein, VEGF production and secretion into the culture medium; and, the effect of a potent, selective inhibitor of VEGF receptors, AL-993, on cell proliferation. Results: Human colorectal cancer specimens had strong expression of VEGF in cancer cells and also expressed VEGF-R1 and VEGF-R2.In vitro studies showed that human colon cancer cell lines, HCT116 and HT29, but not normal colonic cell lines, express VEGF, VEGF-R1 and VEGF-R2 and secrete VEGF into the medium up to a concentration 2000 pg/ml within 48 h. Furthermore, we showed that inhibition of VEGF receptors using a specific VEGF-R inhibitor significantly reduced proliferation (by >50%) of cultured colon cancer cell lines. Conclusions: Our findings support the contention that VEGF generated by colon cancer cells stimulates their growth directly through an autocrine mechanism that is independent of its primary function in the induction of angiogenesis.« less

Transcriptional and post-transcriptional upregulation of p27 mediates growth inhibition of isorhapontigenin (ISO) on human bladder cancer cells.

PubMed

Jiang, Guosong; Huang, Chao; Li, Jingxia; Huang, Haishan; Wang, Jingjing; Li, Yawei; Xie, Fei; Jin, Honglei; Zhu, Junlan; Huang, Chuanshu

2018-03-08

There are few approved drugs available for the treatment of muscle-invasive bladder cancer (MIBC). Recently, we have demonstrated that isorhapontigenin (ISO), a new derivative isolated from the Chinese herb Gnetum cleistostachyum, effectively induces cell-cycle arrest at the G0/G1 phase and inhibits anchorage-independent cell growth through the miR-137/Sp1/cyclin D1 axis in human MIBC cells. Herein, we found that treatment of bladder cancer (BC) cells with ISO resulted in a significant upregulation of p27, which was also observed in ISO-treated mouse BCs that were induced by N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN). Importantly, knockdown of p27 caused a decline in the ISO-induced G0-G1 growth arrest and reversed ISO suppression of anchorage-independent growth in BC cells. Mechanistic studies revealed that ISO promoted p27 expression at mRNA transcription level through increasing direct binding of forkhead box class O1 (FOXO1) to its promoter, while knockdown of FOXO1 attenuated ISO inhibition of BC cell growth. On the other hand, ISO upregulated the 3'-untranslated region (3'-UTR) activity of p27, which was accompanied by a reduction of miR-182 expression. In line with these observations, ectopic expression of miR-182 significantly blocked p27 3'-UTR activity, whereas mutation of the miR-182-binding site at p27 mRNA 3'-UTR effectively reversed this inhibition. Accordingly, ectopic expression of miR-182 also attenuated ISO upregulation of p27 expression and impaired ISO inhibition of BC cell growth. Our results not only provide novel insight into understanding of the underlying mechanism related to regulation of MIBC cell growth but also identify new roles and mechanisms underlying ISO inhibition of BC cell growth.

Sox2 Is an Androgen Receptor-Repressed Gene That Promotes Castration-Resistant Prostate Cancer

PubMed Central

Kregel, Steven; Kiriluk, Kyle J.; Rosen, Alex M.; Cai, Yi; Reyes, Edwin E.; Otto, Kristen B.; Tom, Westin; Paner, Gladell P.; Szmulewitz, Russell Z.; Vander Griend, Donald J.

2013-01-01

Despite advances in detection and therapy, castration-resistant prostate cancer continues to be a major clinical problem. The aberrant activity of stem cell pathways, and their regulation by the Androgen Receptor (AR), has the potential to provide insight into novel mechanisms and pathways to prevent and treat advanced, castrate-resistant prostate cancers. To this end, we investigated the role of the embryonic stem cell regulator Sox2 [SRY (sex determining region Y)-box 2] in normal and malignant prostate epithelial cells. In the normal prostate, Sox2 is expressed in a portion of basal epithelial cells. Prostate tumors were either Sox2-positive or Sox2-negative, with the percentage of Sox2-positive tumors increasing with Gleason Score and metastases. In the castration-resistant prostate cancer cell line CWR-R1, endogenous expression of Sox2 was repressed by AR signaling, and AR chromatin-IP shows that AR binds the enhancer element within the Sox2 promoter. Likewise, in normal prostate epithelial cells and human embryonic stem cells, increased AR signaling also decreases Sox2 expression. Resistance to the anti-androgen MDV3100 results in a marked increase in Sox2 expression within three prostate cancer cell lines, and in the castration-sensitive LAPC-4 prostate cancer cell line ectopic expression of Sox2 was sufficient to promote castration-resistant tumor formation. Loss of Sox2 expression in the castration-resistant CWR-R1 prostate cancer cell line inhibited cell growth. Up-regulation of Sox2 was not associated with increased CD133 expression but was associated with increased FGF5 (Fibroblast Growth Factor 5) expression. These data propose a model of elevated Sox2 expression due to loss of AR-mediated repression during castration, and consequent castration-resistance via mechanisms not involving induction of canonical embryonic stem cell pathways. PMID:23326489

Hyperthyroidism caused by an ectopic thyrotropin-secreting tumor of the nasopharynx: a case report and review of the literature.

PubMed

Tong, Anli; Xia, Weibo; Qi, Fang; Jin, Zimeng; Yang, Di; Zhang, Zhuhua; Li, Fang; Xing, Xiaoping; Lian, Xiaolan

2013-09-01

Ectopic thyrotropin (TSH)-secreting tumors are extremely rare. To our knowledge, only three cases have previously been reported so far, but the tumors were not studied ultrastructurally and in vitro. We present a case that was extensively examined to gain deeper insights in terms of the histopathological features and hormonal secretion profile of the tumor. A 49-year-old female complained of nasal obstruction for 15 years and thyrotoxicosis for one and a half years. Except for a high basal TSH with concomitantly elevated free tri-iodothyronine (FT3) and free thyroxine (FT4) levels, her pituitary hormone profile yielded normal results. Magnetic resonance imaging revealed a 2 cm × 2 cm mass in the nasopharynx, which showed an increased tracer uptake on octreotide scintigraphy. Preoperative treatment with octreotide effectively reduced serum TSH, FT3, and FT4 to normal levels. The mass was endoscopically removed via an endonasal approach. Immunophenotyping and hormone determination of cultured cells confirmed that the mass was a plurihormonal TSH-/growth hormone (GH)-/prolactin (PRL)-producing adenoma. Co-expression of TSH and GH was found in most cells. Electron microscopy showed that the adenoma was formed by a single cell type, with secretory granules of small size. In vitro studies demonstrated that octreotide reduced both TSH and GH secretion. We report an ectopic TSH-secreting tumor, which had plurihormonal secretion in vitro, including TSH, GH, and PRL. Histologically, it mimicked a TSH-secreting pituitary adenoma. Octreotide was useful in the diagnosis and treatment of this ectopic TSH-secreting tumor. Ectopic TSH-secreting tumors are extremely rare. In terms of hormone secretion profile, histological characteristics, and response to octreotide, they are similar to pituitary TSH-secreting adenomas, suggesting that they are of identical cell origin.

Auranofin-mediated inhibition of PI3K/AKT/mTOR axis and anticancer activity in non-small cell lung cancer cells

PubMed Central

Li, Hongyu; Hu, Jing; Wu, Shuhong; Wang, Li; Cao, Xiaobo; Zhang, Xiaoshan; Dai, Bingbing; Cao, Mengru; Shao, Ruping; Zhang, Ran; Majidi, Mourad; Ji, Lin; Heymach, John V.; Wang, Michael; Pan, Shiyang; Minna, John; Mehran, Reza J.; Swisher, Stephen G.; Roth, Jack A.; Fang, Bingliang

2016-01-01

Auranofin, a gold complex that has been used to treat rheumatoid arthritis in clinics and has documented pharmacokinetic and safety profiles in humans, has recently been investigated for its anticancer activity in leukemia and some solid cancers. However, auranofin's single agent activity in lung cancer is not well characterized. To determine whether auranofin has single agent activity in lung cancer, we evaluated auranofin's activity in a panel of 10 non-small cell lung cancer (NSCLC) cell lines. Cell viability analysis revealed that auranofin induced growth inhibition in a subset of NSCLC cell lines with a half maximal inhibitory concentration (IC50) below 1.0 μM. Treatment with auranofin elicited apoptosis and necroptosis in auranofin-sensitive cell lines. Moreover, the susceptibility of NSCLC cells to auranofin was inversely correlated with TXNRD1 expression in the cells. Transient transfection of the TXNRD1-expressing plasmid in auranofin-sensitive Calu3 cells resulted in partial resistance, indicating that high TXNRD level is one of causal factors for resistance to auranofin. Further mechanistic characterization with proteomic analysis revealed that auranofin inhibits expression and/or phosphorylation of multiple key nodes in the PI3K/AKT/mTOR pathway, including S6, 4EBP1, Rictor, p70S6K, mTOR, TSC2, AKT and GSK3. Ectopic expression of TXNRD1 partially reversed auranofin-mediated PI3K/AKT/mTOR inhibition, suggesting that TXNRD1 may participate in the regulation of PI3K/AKT/mTOR pathway. Administration of auranofin to mice with xenograft tumors derived from NSCLC cells significantly suppressed tumor growth without inducing obvious toxic effects. Our results demonstrated feasibility of repurposing auranofin for treatment of lung cancer. PMID:26657290

The binding protein BiP attenuates stress-induced cell death in soybean via modulation of the N-rich protein-mediated signaling pathway.

PubMed

Reis, Pedro A A; Rosado, Gustavo L; Silva, Lucas A C; Oliveira, Luciana C; Oliveira, Lucas B; Costa, Maximiller D L; Alvim, Fátima C; Fontes, Elizabeth P B

2011-12-01

The molecular chaperone binding protein (BiP) participates in the constitutive function of the endoplasmic reticulum (ER) and protects the cell against stresses. In this study, we investigated the underlying mechanism by which BiP protects plant cells from stress-induced cell death. We found that enhanced expression of BiP in soybean (Glycine max) attenuated ER stress- and osmotic stress-mediated cell death. Ectopic expression of BiP in transgenic lines attenuated the leaf necrotic lesions that are caused by the ER stress inducer tunicamycin and also maintained shoot turgidity upon polyethylene glycol-induced dehydration. BiP-mediated attenuation of stress-induced cell death was confirmed by the decreased percentage of dead cell, the reduced induction of the senescence-associated marker gene GmCystP, and reduced DNA fragmentation in BiP-overexpressing lines. These phenotypes were accompanied by a delay in the induction of the cell death marker genes N-RICH PROTEIN-A (NRP-A), NRP-B, and GmNAC6, which are involved in transducing a cell death signal generated by ER stress and osmotic stress through the NRP-mediated signaling pathway. The prosurvival effect of BiP was associated with modulation of the ER stress- and osmotic stress-induced NRP-mediated cell death signaling, as determined in transgenic tobacco (Nicotiana tabacum) lines with enhanced (sense) and suppressed (antisense) BiP levels. Enhanced expression of BiP prevented NRP- and NAC6-mediated chlorosis and the appearance of senescence-associated markers, whereas silencing of endogenous BiP accelerated the onset of leaf senescence mediated by NRPs and GmNAC6. Collectively, these results implicate BiP as a negative regulator of the stress-induced NRP-mediated cell death response.

The Binding Protein BiP Attenuates Stress-Induced Cell Death in Soybean via Modulation of the N-Rich Protein-Mediated Signaling Pathway1[C][W][OA

PubMed Central

Reis, Pedro A.A.; Rosado, Gustavo L.; Silva, Lucas A.C.; Oliveira, Luciana C.; Oliveira, Lucas B.; Costa, Maximiller D.L.; Alvim, Fátima C.; Fontes, Elizabeth P.B.

2011-01-01

The molecular chaperone binding protein (BiP) participates in the constitutive function of the endoplasmic reticulum (ER) and protects the cell against stresses. In this study, we investigated the underlying mechanism by which BiP protects plant cells from stress-induced cell death. We found that enhanced expression of BiP in soybean (Glycine max) attenuated ER stress- and osmotic stress-mediated cell death. Ectopic expression of BiP in transgenic lines attenuated the leaf necrotic lesions that are caused by the ER stress inducer tunicamycin and also maintained shoot turgidity upon polyethylene glycol-induced dehydration. BiP-mediated attenuation of stress-induced cell death was confirmed by the decreased percentage of dead cell, the reduced induction of the senescence-associated marker gene GmCystP, and reduced DNA fragmentation in BiP-overexpressing lines. These phenotypes were accompanied by a delay in the induction of the cell death marker genes N-RICH PROTEIN-A (NRP-A), NRP-B, and GmNAC6, which are involved in transducing a cell death signal generated by ER stress and osmotic stress through the NRP-mediated signaling pathway. The prosurvival effect of BiP was associated with modulation of the ER stress- and osmotic stress-induced NRP-mediated cell death signaling, as determined in transgenic tobacco (Nicotiana tabacum) lines with enhanced (sense) and suppressed (antisense) BiP levels. Enhanced expression of BiP prevented NRP- and NAC6-mediated chlorosis and the appearance of senescence-associated markers, whereas silencing of endogenous BiP accelerated the onset of leaf senescence mediated by NRPs and GmNAC6. Collectively, these results implicate BiP as a negative regulator of the stress-induced NRP-mediated cell death response. PMID:22007022

RUNX3 is oncogenic in natural killer/T-cell lymphoma and is transcriptionally regulated by MYC

PubMed Central

Selvarajan, V; Osato, M; Nah, G S S; Yan, J; Chung, T-H; Voon, D C-C; Ito, Y; Ham, M F; Salto-Tellez, M; Shimizu, N; Choo, S-N; Fan, S; Chng, W-J; Ng, S-B

2017-01-01

RUNX3, runt-domain transcription factor, is a master regulator of gene expression in major developmental pathways. It acts as a tumor suppressor in many cancers but is oncogenic in certain tumors. We observed upregulation of RUNX3 mRNA and protein expression in nasal-type extranodal natural killer (NK)/T-cell lymphoma (NKTL) patient samples and NKTL cell lines compared to normal NK cells. RUNX3 silenced NKTL cells showed increased apoptosis and reduced cell proliferation. Potential binding sites for MYC were identified in the RUNX3 enhancer region. Chromatin immunoprecipitation–quantitative PCR revealed binding activity between MYC and RUNX3. Co-transfection of the MYC expression vector with RUNX3 enhancer reporter plasmid resulted in activation of RUNX3 enhancer indicating that MYC positively regulates RUNX3 transcription in NKTL cell lines. Treatment with a small-molecule MYC inhibitor (JQ1) caused significant downregulation of MYC and RUNX3, leading to apoptosis in NKTL cells. The growth inhibition resulting from depletion of MYC by JQ1 was rescued by ectopic MYC expression. In summary, our study identified RUNX3 overexpression in NKTL with functional oncogenic properties. We further delineate that MYC may be an important upstream driver of RUNX3 upregulation and since MYC is upregulated in NKTL, further study on the employment of MYC inhibition as a therapeutic strategy is warranted. PMID:28119527

Ectopic Cushing' syndrome caused by a neuroendocrine carcinoma of the mesentery.

PubMed

Fasshauer, Mathias; Lincke, Thomas; Witzigmann, Helmut; Kluge, Regine; Tannapfel, Andrea; Moche, Michael; Buchfelder, Michael; Petersenn, Stephan; Kratzsch, Juergen; Paschke, Ralf; Koch, Christian A

2006-04-27

ACTH overproduction within the pituitary gland or ectopically leads to hypercortisolism. Here, we report the first case of Cushing' syndrome caused by an ectopic ACTH-secreting neuroendocrine carcinoma of the mesentery. Moreover, diagnostic procedures and pitfalls associated with ectopic ACTH-secreting tumors are demonstrated and discussed. A 41 year-old man presented with clinical features and biochemical tests suggestive of ectopic Cushing's syndrome. First, subtotal thyroidectomy was performed without remission of hypercortisolism, because an octreotide scan showed increased activity in the left thyroid gland and an ultrasound revealed nodules in both thyroid lobes one of which was autonomous. In addition, the patient had a 3 mm hypoenhancing lesion of the neurohypophysis and a 1 cm large adrenal tumor. Surgical removal of the pituitary lesion within the posterior lobe did not improve hypercortisolism and we continued to treat the patient with metyrapone to block cortisol production. At 18-months follow-up from initial presentation, we detected an ACTH-producing neuroendocrine carcinoma of the mesentery by using a combination of octreotide scan, computed tomography scan, and positron emission tomography. Intraoperatively, use of a gamma probe after administration of radiolabeled (111)In-pentetreotide helped identify the mesenteric neuroendocrine tumor. After removal of this carcinoma, the patient improved clinically. Laboratory testing confirmed remission of hypercortisolism. An octreotide scan 7 months after surgery showed normal results. This case underscores the diagnostic challenge in identifying an ectopic ACTH-producing tumor and the pluripotency of cells, in this case of mesenteric cells that can start producing and secreting ACTH. It thereby helps elucidate the pathogenesis of neuroendocrine tumors. This case also suggests that patients with ectopic Cushing's syndrome and an octreotide scan positive in atypical locations may benefit from explorative radioguided surgery using (111)In-pentetreotide and a gamma probe.

Ectopic Cushing' syndrome caused by a neuroendocrine carcinoma of the mesentery

PubMed Central

Fasshauer, Mathias; Lincke, Thomas; Witzigmann, Helmut; Kluge, Regine; Tannapfel, Andrea; Moche, Michael; Buchfelder, Michael; Petersenn, Stephan; Kratzsch, Juergen; Paschke, Ralf; Koch, Christian A

2006-01-01

Background ACTH overproduction within the pituitary gland or ectopically leads to hypercortisolism. Here, we report the first case of Cushing' syndrome caused by an ectopic ACTH-secreting neuroendocrine carcinoma of the mesentery. Moreover, diagnostic procedures and pitfalls associated with ectopic ACTH-secreting tumors are demonstrated and discussed. Case presentation A 41 year-old man presented with clinical features and biochemical tests suggestive of ectopic Cushing's syndrome. First, subtotal thyroidectomy was performed without remission of hypercortisolism, because an octreotide scan showed increased activity in the left thyroid gland and an ultrasound revealed nodules in both thyroid lobes one of which was autonomous. In addition, the patient had a 3 mm hypoenhancing lesion of the neurohypophysis and a 1 cm large adrenal tumor. Surgical removal of the pituitary lesion within the posterior lobe did not improve hypercortisolism and we continued to treat the patient with metyrapone to block cortisol production. At 18-months follow-up from initial presentation, we detected an ACTH-producing neuroendocrine carcinoma of the mesentery by using a combination of octreotide scan, computed tomography scan, and positron emission tomography. Intraoperatively, use of a gamma probe after administration of radiolabeled 111In-pentetreotide helped identify the mesenteric neuroendocrine tumor. After removal of this carcinoma, the patient improved clinically. Laboratory testing confirmed remission of hypercortisolism. An octreotide scan 7 months after surgery showed normal results. Conclusion This case underscores the diagnostic challenge in identifying an ectopic ACTH-producing tumor and the pluripotency of cells, in this case of mesenteric cells that can start producing and secreting ACTH. It thereby helps elucidate the pathogenesis of neuroendocrine tumors. This case also suggests that patients with ectopic Cushing's syndrome and an octreotide scan positive in atypical locations may benefit from explorative radioguided surgery using 111In-pentetreotide and a gamma probe. PMID:16643652

Compensatory branching morphogenesis of stalk cells in the Drosophila trachea.

PubMed

Francis, Deanne; Ghabrial, Amin S

2015-06-01

Tubes are essential for nutrient transport and gas exchange in multicellular eukaryotes, but how connections between different tube types are maintained over time is unknown. In the Drosophila tracheal system, mutations in oak gall (okg) and conjoined (cnj) confer identical defects, including late onset blockage near the terminal cell-stalk cell junction and the ectopic extension of autocellular, seamed tubes into the terminal cell. We determined that okg and cnj encode the E and G subunits of the vacuolar ATPase (vATPase) and showed that both the V0 and V1 domains are required for terminal cell morphogenesis. Remarkably, the ectopic seamed tubes running along vATPase-deficient terminal cells belonged to the neighboring stalk cells. All vATPase-deficient tracheal cells had reduced apical domains and terminal cells displayed mislocalized apical proteins. Consistent with recent reports that the mTOR and vATPase pathways intersect, we found that mTOR pathway mutants phenocopied okg and cnj. Furthermore, terminal cells depleted for the apical determinants Par6 or aPKC had identical ectopic seamed tube defects. We thus identify a novel mechanism of compensatory branching in which stalk cells extend autocellular tubes into neighboring terminal cells with undersized apical domains. This compensatory branching also occurs in response to injury, with damaged terminal cells being rapidly invaded by their stalk cell neighbor. © 2015. Published by The Company of Biologists Ltd.

MicroRNA-101-3p suppresses cell proliferation, invasion and enhances chemotherapeutic sensitivity in salivary gland adenoid cystic carcinoma by targeting Pim-1

PubMed Central

Liu, Xiao-Yu; Liu, Zhi-Jian; He, Hong; Zhang, Chen; Wang, Yun-Long

2015-01-01

MicroRNAs (miRNAs) play critical roles in carcinogenesis and tumor progression. Recent research has revealed miR-101-3p as an important regulator in several cancers. Nevertheless, its function in salivary gland Adenoid cystic carcinoma (ACC), a relatively rare malignance with poor long-term survival rate arisen in head and neck region, remain unknown. In this study, down-regulated miR-101-3p expression was detected in ACC tissues and ACC cell lines with high potential for metastasis. Ectopic expression of miR-101-3p significantly repressed the invasion, proliferation, colony formation, and formation of nude mice xenografts and induced potent apoptosis in ACC cell lines. The provirus integration site for Moloney murine leukemia virus 1 (Pim-1) oncogene was subsequently confirmed as a direct target gene of miR-101-3p in ACC. Functional restoration assays revealed that miR-101-3p inhibits cell growth and invasion by directly decreasing Pim-1 expression. Protein levels of Survivin, Cyclin D1 and β-catenin were also down-regulated by miR-101-3p. miR-101-3p enhanced the sensitivity of cisplatin in ACC cell lines. Taken together, our results demonstrate that the novel miR-101-3p/Pim-1 axis provides excellent insights into the carcinogenesis and tumor progression of ACC and may be a promising therapeutic target for this type of cancer. PMID:26693056

Caveolin-1 down-regulates inducible nitric oxide synthase via the proteasome pathway in human colon carcinoma cells

PubMed Central

Felley-Bosco, Emanuela; Bender, Florent C.; Courjault-Gautier, Françoise; Bron, Claude; Quest, Andrew F. G.

2000-01-01

To investigate whether caveolin-1 (cav-1) may modulate inducible nitric oxide synthase (iNOS) function in intact cells, the human intestinal carcinoma cell lines HT29 and DLD1 that have low endogenous cav-1 levels were transfected with cav-1 cDNA. In nontransfected cells, iNOS mRNA and protein levels were increased by the addition of a mix of cytokines. Ectopic expression of cav-1 in both cell lines correlated with significantly decreased iNOS activity and protein levels. This effect was linked to a posttranscriptional mechanism involving enhanced iNOS protein degradation by the proteasome pathway, because (i) induction of iNOS mRNA by cytokines was not affected and (ii) iNOS protein levels increased in the presence of the proteasome inhibitors N-acetyl-Leu-Leu-Norleucinal and lactacystin. In addition, a small amount of iNOS was found to cofractionate with cav-1 in Triton X-100-insoluble membrane fractions where also iNOS degradation was apparent. As has been described for endothelial and neuronal NOS isoenzymes, direct binding between cav-1 and human iNOS was detected in vitro. Taken together, these results suggest that cav-1 promotes iNOS presence in detergent-insoluble membrane fractions and degradation there via the proteasome pathway. PMID:11114180

Dysregulated endocardial TGFβ signaling and mesenchymal transformation result in heart outflow tract septation failure.

PubMed

Ma, Mancheong; Li, Peng; Shen, Hua; Estrada, Kristine D; Xu, Jian; Kumar, S Ram; Sucov, Henry M

2016-01-01

Heart outflow tract septation in mouse embryos carrying mutations in retinoic acid receptor genes fails with complete penetrance. In this mutant background, ectopic TGFβ signaling in the distal outflow tract is responsible for septation failure, but it was uncertain what tissue was responsive to ectopic TGFβ and why this response interfered with septation. By combining RAR gene mutation with tissue-specific Cre drivers and a conditional type II TGFβ receptor (Tgfbr2) allele, we determined that ectopic activation of TGFβ signaling in the endocardium is responsible for septation defects. Ectopic TGFβ signaling results in ectopic mesenchymal transformation of the endocardium and thereby in improperly constituted distal OFT cushions. Our analysis highlights the interactions between myocardium, endocardium, and neural crest cells in outflow tract morphogenesis, and demonstrates the requirement for proper TGFβ signaling in outflow tract cushion organization and septation. Copyright © 2015. Published by Elsevier Inc.

Direct Reprogramming of Mouse Fibroblasts into Functional Skeletal Muscle Progenitors.

PubMed

Bar-Nur, Ori; Gerli, Mattia F M; Di Stefano, Bruno; Almada, Albert E; Galvin, Amy; Coffey, Amy; Huebner, Aaron J; Feige, Peter; Verheul, Cassandra; Cheung, Priscilla; Payzin-Dogru, Duygu; Paisant, Sylvain; Anselmo, Anthony; Sadreyev, Ruslan I; Ott, Harald C; Tajbakhsh, Shahragim; Rudnicki, Michael A; Wagers, Amy J; Hochedlinger, Konrad

2018-05-08

Skeletal muscle harbors quiescent stem cells termed satellite cells and proliferative progenitors termed myoblasts, which play pivotal roles during muscle regeneration. However, current technology does not allow permanent capture of these cell populations in vitro. Here, we show that ectopic expression of the myogenic transcription factor MyoD, combined with exposure to small molecules, reprograms mouse fibroblasts into expandable induced myogenic progenitor cells (iMPCs). iMPCs express key skeletal muscle stem and progenitor cell markers including Pax7 and Myf5 and give rise to dystrophin-expressing myofibers upon transplantation in vivo. Notably, a subset of transplanted iMPCs maintain Pax7 expression and sustain serial regenerative responses. Similar to satellite cells, iMPCs originate from Pax7 + cells and require Pax7 itself for maintenance. Finally, we show that myogenic progenitor cell lines can be established from muscle tissue following small-molecule exposure alone. This study thus reports on a robust approach to derive expandable myogenic stem/progenitor-like cells from multiple cell types. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

PSMB4 promotes multiple myeloma cell growth by activating NF-κB-miR-21 signaling

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

Zheng, Peihao; Guo, Honggang; Li, Guangchao

2015-03-06

Proteasomal subunit PSMB4, was recently identified as potential cancer driver genes in several tumors. However, the regulatory mechanism of PSMB4 on carcinogenesis process remains unclear. In this study, we investigated the expression and roles of PSMB4 in multiple myeloma (MM). We found a significant up-regulation of PSMB4 in MM plasma and cell lines. Ectopic overexpression of PSMB4 promoted cell growth and colony forming ability of MM cells, whereas inhibition of PSMB4 led to a decrease of such events. Furthermore, our results demonstrated the up-regulation of miR-21 and a positive correlation between the levels of miR-21 and PSMB4 in MM. Re-expressionmore » of miR-21 markedly rescued PSMB4 knockdown-mediated suppression of cell proliferation and clone-formation. Additionally, while enforced expression of PSMB4 profoundly increased NF-κB activity and the level of miR-21, PSMB4 knockdown or NF-κB inhibition suppressed miR-21 expression in MM cells. Taken together, our results demonstrated that PSMB4 regulated MM cell growth in part by activating NF-κB-miR-21 signaling, which may represent promising targets for novel specific therapies. - Highlights: • First reported upregulation of PSMB4 in MM plasma and cell lines. • PSMB4 promoted MM cell growth and colony forming ability. • Further found miR-21 was up-regulated by PSMB4 in MM plasma and cell lines. • PSMB4-induced miR-21 expression was modulated by NF-κB. • PSMB4-NF-κB-miR-21 axis may be potential therapeutic targets of MM.« less

CREG1 enhances p16INK4a-induced cellular senescence

PubMed Central

Moolmuang, Benchamart

2011-01-01

Cellular senescence is an irreversible growth arrest that is activated in normal cells upon shortening of telomere and other cellular stresses. Bypassing cellular senescence is a necessary step for cells to become immortal during oncogenic transformation. During the spontaneous immortalization of Li-Fraumeni Syndrome (LFS) fibroblasts, we found that CREG1 (Cellular Repressor of E1A-stimulated Genes 1) expression was decreased during immortalization and increased in senescence. Moreover, we found that repression of CREG1 expression occurs via an epigenetic mechanism, promoter DNA methylation. Ectopic expression of CREG1 in the immortal LFS cell lines decreases cell proliferation but does not directly induce senescence. We confirmed this in osteosarcoma and fibrosarcoma cancer cell lines, cancers commonly seen in Li-Fraumeni Syndrome. In addition, we found that p16INK4a is also downregulated in immortal cells and that coexpression of CREG1 and p16INK4a, an inhibitor of CDK4/6 and Rb phosphorylation, has a greater effect than either CREG1 and p16INK4a alone to reduce cell growth, induce cell cycle arrest and cellular senescence in immortal LFS fibroblasts, osteosarcoma and fibrosarcoma cell lines. Moreover, cooperation of CREG1 and p16INK4a inhibits the expression of cyclin A and cyclin B by inhibiting promoter activity, thereby decreasing mRNA and protein levels; these proteins are required for S-phase entry and G2/M transition. In conclusion, this is the first evidence to demonstrate that CREG1 enhances p16INK4a-induced senescence by transcriptional repression of cell cycle-regulated genes. PMID:21263217

Hsa-mir-182 suppresses lung tumorigenesis through down regulation of RGS17 expression in vitro

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

Sun, Yihua; Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Science, Shanghai 200031; Fang, Rong

2010-05-28

Lung cancer is one of the most devastating diseases worldwide. RGS17 is previously shown to be over-expressed in human lung adenocarcinomas and plays an important role in lung tumor growth. Here we have identified a miRNA, has-mir-182, involved in the regulation of RGS17 expression through two conserved sites located in its 3' UTR region. Consistently, endogenous RGS17 expression level is regulated by hsa-mir-182 in human lung cancer cell lines. Similar to the knockdown of RGS17, ectopic expression of hsa-mir-182 significantly inhibits lung cancer cell proliferation and anchorage-independent cell growth, which can be rescued by re-expression of RGS17. Taken together, thesemore » data have provided the first evidence of miRNA regulation of RGS17 expression in lung cancer.« less

Pneumocystis Pneumonia Concomitant with Ectopic ACTH Syndrome Caused by a Large Cell Neuroendocrine Carcinoma of the Thymus.

PubMed

Oda, Naohiro; Miyahara, Nobuaki; Tabata, Masahiro; Minami, Daisuke; Ninomiya, Kiichiro; Kanehiro, Arihiko; Komatsubara, Motoshi; Inagaki, Kenichi; Tanimoto, Mitsune; Kiura, Katsuyuki

2017-01-01

We herein report the case of a 44-year-old man who was diagnosed with pneumocystis pneumonia (PCP) concomitant with ectopic adrenocorticotropic hormone (ACTH) syndrome, which had been caused by a large cell neuroendocrine carcinoma of the thymus. Chest computed tomography revealed ground-glass opacities in the lungs. PCP was diagnosed by a polymerase chain reaction with bronchoalveolar lavage. The levels of cortisol were slowly corrected with an adrenal enzyme inhibitor, and the exacerbation of PCP was successfully avoided. Our case indicates that in addition to prophylaxis, the early diagnosis of PCP and the slow correction of hypercortisolemia should be considered in order to prevent an exacerbation due to the reconstitution of the immune function in patients with ectopic ACTH syndrome.

MicroRNA-187-3p mitigates non-small cell lung cancer (NSCLC) development through down-regulation of BCL6

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

Sun, Chengcao; Li, Shujun; Wuhan Hospital for the Prevention and Treatment of Occupational Diseases, 430071 Wuhan

2016-02-26

Hsa-microRNA-187-3p (miR-187-3p) has recently been discovered having anticancer efficacy in different organs. However, the role of miR-187-3p on non-small cell lung cancer (NSCLC) is still ambiguous. In this study, we investigated the role of miR-187-3p on the development of NSCLC. The results indicated that miR-187-3p was significantly down-regulated in primary tumor tissues and very low levels were found in NSCLC cell lines. Ectopic expression of miR-187-3p in NSCLC cell lines significantly suppressed cell growth as evidenced by cell viability assay and colony formation assay, through inhibition of BCL6. In addition, miR-187-3p induced apoptosis, as indicated by concomitantly with up-regulation ofmore » the activities of caspase-3 and caspase-7, and inhibited cellular migration and invasiveness through inhibition of BCL6. Further, oncogene BCL6 was revealed to be a putative target of miR-187-3p, which was inversely correlated with miR-187-3p expression in NSCLC. Taken together, our results demonstrated that miR-187-3p played a pivotal role on NSCLC through inhibiting cell proliferation, migration, invasion, and promoting apoptosis by targeting oncogenic BCL6.« less

CD63 tetraspanin is a negative driver of epithelial-to-mesenchymal transition in human melanoma cells.

PubMed

Lupia, Antonella; Peppicelli, Silvia; Witort, Ewa; Bianchini, Francesca; Carloni, Vinicio; Pimpinelli, Nicola; Urso, Carmelo; Borgognoni, Lorenzo; Capaccioli, Sergio; Calorini, Lido; Lulli, Matteo

2014-12-01

The CD63 tetraspanin is highly expressed in the early stages of melanoma and decreases in advanced lesions, suggesting it as a possible suppressor of tumor progression. We employed loss- and gain-of-gene-function approaches to investigate the role of CD63 in melanoma progression and acquisition of the epithelial-to-mesenchymal transition (EMT) program. We used two human melanoma cell lines derived from primary tumors and one primary human melanoma cell line isolated from a cutaneous metastasis, differing by levels of CD63 expression. CD63-silenced melanoma cells showed enhanced motility and invasiveness with downregulation of E-cadherin and upregulation of N-cadherin and Snail. In parallel experiments, transient and stable ectopic expression of CD63 resulted in a robust reduction of cell motility, invasiveness, and protease activities, which was proportional to the increase in CD63 protein level. Transfected cells overexpressing the highest level of CD63 when transplanted into immunodeficient mice showed a reduced incidence and rate of tumor growth. Moreover, these cells showed a reduction of N-cadherin, Vimentin, Zeb1, and a-SMA, and a significant resistance to undergo an EMT program both in basal condition and in the following stimulation with TGFβ. Thus, our results establish a previously unreported mechanistic link between the tetraspanin CD63 and EMT abrogation in melanoma.

Bar represses dPax2 and decapentaplegic to regulate cell fate and morphogenetic cell death in Drosophila eye.

PubMed

Kang, Jongkyun; Yeom, Eunbyul; Lim, Janghoo; Choi, Kwang-Wook

2014-01-01

The coordinated regulation of cell fate and cell survival is crucial for normal pattern formation in developing organisms. In Drosophila compound eye development, crystalline arrays of hexagonal ommatidia are established by precise assembly of diverse cell types, including the photoreceptor cells, cone cells and interommatidial (IOM) pigment cells. The molecular basis for controlling the number of cone and IOM pigment cells during ommatidial pattern formation is not well understood. Here we present evidence that BarH1 and BarH2 homeobox genes are essential for eye patterning by inhibiting excess cone cell differentiation and promoting programmed death of IOM cells. Specifically, we show that loss of Bar from the undifferentiated retinal precursor cells leads to ectopic expression of Prospero and dPax2, two transcription factors essential for cone cell specification, resulting in excess cone cell differentiation. We also show that loss of Bar causes ectopic expression of the TGFβ homolog Decapentaplegic (Dpp) posterior to the morphogenetic furrow in the larval eye imaginal disc. The ectopic Dpp expression is not responsible for the formation of excess cone cells in Bar loss-of-function mutant eyes. Instead, it causes reduction in IOM cell death in the pupal stage by antagonizing the function of pro-apoptotic gene reaper. Taken together, this study suggests a novel regulatory mechanism in the control of developmental cell death in which the repression of Dpp by Bar in larval eye disc is essential for IOM cell death in pupal retina.

Transplantation of conditionally immortal auditory neuroblasts to the auditory nerve.

PubMed

Sekiya, Tetsuji; Holley, Matthew C; Kojima, Ken; Matsumoto, Masahiro; Helyer, Richard; Ito, Juichi

2007-04-01

Cell transplantation is a realistic potential therapy for replacement of auditory sensory neurons and could benefit patients with cochlear implants or acoustic neuropathies. The procedure involves many experimental variables, including the nature and conditioning of donor cells, surgical technique and degree of degeneration in the host tissue. It is essential to control these variables in order to develop cell transplantation techniques effectively. We have characterized a conditionally immortal, mouse cell line suitable for transplantation to the auditory nerve. Structural and physiological markers defined the cells as early auditory neuroblasts that lacked neuronal, voltage-gated sodium or calcium currents and had an undifferentiated morphology. When transplanted into the auditory nerves of rats in vivo, the cells migrated peripherally and centrally and aggregated to form coherent, ectopic 'ganglia'. After 7 days they expressed beta 3-tubulin and adopted a similar morphology to native spiral ganglion neurons. They also developed bipolar projections aligned with the host nerves. There was no evidence for uncontrolled proliferation in vivo and cells survived for at least 63 days. If cells were transplanted with the appropriate surgical technique then the auditory brainstem responses were preserved. We have shown that immortal cell lines can potentially be used in the mammalian ear, that it is possible to differentiate significant numbers of cells within the auditory nerve tract and that surgery and cell injection can be achieved with no damage to the cochlea and with minimal degradation of the auditory brainstem response.

A Multistate Toggle Switch Defines Fungal Cell Fates and Is Regulated by Synergistic Genetic Cues

PubMed Central

Anderson, Matthew Z.; Porman, Allison M.; Wang, Na; Mancera, Eugenio; Bennett, Richard J.

2016-01-01

Heritable epigenetic changes underlie the ability of cells to differentiate into distinct cell types. Here, we demonstrate that the fungal pathogen Candida tropicalis exhibits multipotency, undergoing stochastic and reversible switching between three cellular states. The three cell states exhibit unique cellular morphologies, growth rates, and global gene expression profiles. Genetic analysis identified six transcription factors that play key roles in regulating cell differentiation. In particular, we show that forced expression of Wor1 or Efg1 transcription factors can be used to manipulate transitions between all three cell states. A model for tristability is proposed in which Wor1 and Efg1 are self-activating but mutually antagonistic transcription factors, thereby forming a symmetrical self-activating toggle switch. We explicitly test this model and show that ectopic expression of WOR1 can induce white-to-hybrid-to-opaque switching, whereas ectopic expression of EFG1 drives switching in the opposite direction, from opaque-to-hybrid-to-white cell states. We also address the stability of induced cell states and demonstrate that stable differentiation events require ectopic gene expression in combination with chromatin-based cues. These studies therefore experimentally test a model of multistate stability and demonstrate that transcriptional circuits act synergistically with chromatin-based changes to drive cell state transitions. We also establish close mechanistic parallels between phenotypic switching in unicellular fungi and cell fate decisions during stem cell reprogramming. PMID:27711197

The Ras suppressor Rsu-1 binds to the LIM 5 domain of the adaptor protein PINCH1 and participates in adhesion-related functions

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

Dougherty, Gerard W.; Section on Structural Cell Biology, National Institute on Deafness and Communication Disorders; Chopp, Treasa

2005-05-15

Rsu-1 is a highly conserved leucine rich repeat (LRR) protein that is expressed ubiquitously in mammalian cells. Rsu-1 was identified based on its ability to inhibit transformation by Ras, and previous studies demonstrated that ectopic expression of Rsu-1 inhibited anchorage-independent growth of Ras-transformed cells and human tumor cell lines. Using GAL4-based yeast two-hybrid screening, the LIM domain protein, PINCH1, was identified as the binding partner of Rsu-1. PINCH1 is an adaptor protein that localizes to focal adhesions and it has been implicated in the regulation of adhesion functions. Subdomain mapping in yeast revealed that Rsu-1 binds to the LIM 5more » domain of PINCH1, a region not previously identified as a specific binding domain for any other protein. Additional testing demonstrated that PINCH2, which is highly homologous to PINCH1, except in the LIM 5 domain, does not interact with Rsu-1. Glutathione transferase fusion protein binding studies determined that the LRR region of Rsu-1 interacts with PINCH1. Transient expression studies using epitope-tagged Rsu-1 and PINCH1 revealed that Rsu-1 co-immunoprecipitated with PINCH1 and colocalized with vinculin at sites of focal adhesions in mammalian cells. In addition, endogenous P33 Rsu-1 from 293T cells co-immunoprecipitated with transiently expressed myc-tagged PINCH1. Furthermore, RNAi-induced reduction in Rsu-1 RNA and protein inhibited cell attachment, and while previous studies demonstrated that ectopic expression of Rsu-1 inhibited Jun kinase activation, the depletion of Rsu-1 resulted in activation of Jun and p38 stress kinases. These studies demonstrate that Rsu-1 interacts with PINCH1 in mammalian cells and functions, in part, by altering cell adhesion.« less

Ectopic expression of LEAFY COTYLEDON1-LIKE gene and localized auxin accumulation mark embryogenic competence in epiphyllous plants of Helianthus annuus × H. tuberosus

PubMed Central

Chiappetta, A.; Fambrini, M.; Petrarulo, M.; Rapparini, F.; Michelotti, V.; Bruno, L.; Greco, M.; Baraldi, R.; Salvini, M.; Pugliesi, C.; Bitonti, M. B.

2009-01-01

Background and Aims The clone EMB-2 of the interspecific hybrid Helianthus annuus × H. tuberosus provides an interesting system to study molecular and physiological aspects of somatic embryogenesis. Namely, in addition to non-epiphyllous (NEP) leaves that expand normally, EMB-2 produces epiphyllous (EP) leaves bearing embryos on the adaxial surface. This clone was used to investigate if the ectopic expression of H. annuus LEAFY COTYLEDON1-LIKE (Ha-L1L) gene and auxin activity are correlated with the establishment of embryogenic competence. Methods Ha-L1L expression was evaluated by semi-quantitative RT-PCR and in situ hybridization. The endogenous level and spatial distribution of free indole-3-acetic acid (IAA) were estimated by a capillary gas chromatography–mass spectrometry–selected ion monitoring method and an immuno-cytochemical approach. Key Results Ectopic expression of Ha-L1L was detected in specific cell domains of the adaxial epidermis of EP leaves prior to the development of ectopic embryos. Ha-L1L was expressed rapidly when NEP leaves were induced to regenerate somatic embryos by in vitro culture. Differences in auxin distribution pattern rather than in absolute level were observed between EP and A-2 leaves. More precisely, a strong IAA immuno-signal was detected in single cells or in small groups of cells along the epidermis of EP leaves and accompanied the early stages of embryo development. Changes in auxin level and distribution were observed in NEP leaves induced to regenerate by in vitro culture. Exogenous auxin treatments lightly influenced Ha-L1L transcript levels in spite of an enhancement of the regeneration frequency. Conclusions In EP leaves, Ha-L1L activity marks the putative founder cells of ectopic embryos. Although the ectopic expression of Ha-L1L seems to be not directly mediated by auxin levels per se, it was demonstrated that localized Ha-L1L expression and IAA accumulation in leaf epidermis domains represent early events of somatic embryogenesis displayed by the epiphyllous EMB-2 clone. PMID:19151043

Nanos genes and their role in development and beyond.

PubMed

De Keuckelaere, Evi; Hulpiau, Paco; Saeys, Yvan; Berx, Geert; van Roy, Frans

2018-06-01

The hallmark of Nanos proteins is their typical (CCHC) 2 zinc finger motif (zf-nanos). Animals have one to four nanos genes. For example, the fruit fly and demosponge have only one nanos gene, zebrafish and humans have three, and Fugu rubripes has four. Nanos genes are mainly known for their evolutionarily preserved role in germ cell survival and pluripotency. Nanos proteins have been reported to bind the C-terminal RNA-binding domain of Pumilio to form a post-transcriptional repressor complex. Several observations point to a link between the miRNA-mediated repression complex and the Nanos/Pumilio complex. Repression of the E2F3 oncogene product is, indeed, mediated by cooperation between the Nanos/Pumilio complex and miRNAs. Another important interaction partner of Nanos is the CCR4-NOT deadenylase complex. Besides the tissue-specific contribution of Nanos proteins to normal development, their ectopic expression has been observed in several cancer cell lines and various human cancers. An inverse correlation between the expression levels of human Nanos1 and Nanos3 and E-cadherin was observed in several cancer cell lines. Loss of E-cadherin, an important cell-cell adhesion protein, contributes to tumor invasion and metastasis. Overexpression of Nanos3 induces epithelial-mesenchymal transition in lung cancer cell lines partly by repressing E-cadherin. Other than some most interesting data from Nanos knockout mice, little is known about mammalian Nanos proteins, and further research is needed. In this review, we summarize the main roles of Nanos proteins and discuss the emerging concept of Nanos proteins as oncofetal antigens.

Elicitors and defense gene induction in plants with altered lignin compositions.

PubMed

Gallego-Giraldo, Lina; Posé, Sara; Pattathil, Sivakumar; Peralta, Angelo Gabriel; Hahn, Michael G; Ayre, Brian G; Sunuwar, Janak; Hernandez, Jonathan; Patel, Monika; Shah, Jyoti; Rao, Xiaolan; Knox, J Paul; Dixon, Richard A

2018-06-27

A reduction in the lignin content in transgenic plants induces the ectopic expression of defense genes, but the importance of altered lignin composition in such phenomena remains unclear. Two Arabidopsis lines with similar lignin contents, but strikingly different lignin compositions, exhibited different quantitative and qualitative transcriptional responses. Plants with lignin composed primarily of guaiacyl units overexpressed genes responsive to oomycete and bacterial pathogen attack, whereas plants with lignin composed primarily of syringyl units expressed a far greater number of defense genes, including some associated with cis-jasmone-mediated responses to aphids; these plants exhibited altered responsiveness to bacterial and aphid inoculation. Several of the defense genes were differentially induced by water-soluble extracts from cell walls of plants of the two lines. Glycome profiling, fractionation and enzymatic digestion studies indicated that the different lignin compositions led to differential extractability of a range of heterogeneous oligosaccharide epitopes, with elicitor activity originating from different cell wall polymers. Alteration of lignin composition affects interactions with plant cell wall matrix polysaccharides to alter the sequestration of multiple latent defense signal molecules with an impact on biotic stress responses. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

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

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

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

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

Epigenetic silencing of ADAMTS18 promotes cell migration and invasion of breast cancer through AKT and NF-κB signaling.

PubMed

Xu, Hongying; Xiao, Qian; Fan, Yu; Xiang, Tingxiu; Li, Chen; Li, Chunhong; Li, Shuman; Hui, Tianli; Zhang, Lu; Li, Hongzhong; Li, Lili; Ren, Guosheng

2017-06-01

ADAMTS18 dysregulation plays an important role in many disease processes including cancer. We previously found ADAMTS18 as frequently methylated tumor suppressor gene (TSG) for multiple carcinomas, however, its biological functions and underlying molecular mechanisms in breast carcinogenesis remain unknown. Here, we found that ADAMTS18 was silenced or downregulated in breast cancer cell lines. ADAMTS18 was reduced in primary breast tumor tissues as compared with their adjacent noncancer tissues. ADAMTS18 promoter methylation was detected in 70.8% of tumor tissues by methylation-specific PCR, but none of the normal tissues. Demethylation treatment restored ADAMTS18 expression in silenced breast cell lines. Ectopic expression of ADAMTS18 in breast tumor cells resulted in inhibition of cell migration and invasion. Nude mouse model further confirmed that ADAMTS18 suppressed breast cancer metastasis in vivo. Further mechanistic studies showed that ADAMTS18 suppressed epithelial-mesenchymal transition (EMT), further inhibited migration and invasion of breast cancer cells. ADAMT18 deregulated AKT and NF-κB signaling, through inhibiting phosphorylation levels of AKT and p65. Thus, ADAMTS18 as an antimetastatic tumor suppressor antagonizes AKT and NF-κB signaling in breast tumorigenesis. Its methylation could be a potential tumor biomarker for breast cancer. © 2017 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

4E-BP1 regulates the differentiation of white adipose tissue.

PubMed

Tsukiyama-Kohara, Kyoko; Katsume, Asao; Kimura, Kazuhiro; Saito, Masayuki; Kohara, Michinori

2013-07-01

4E Binding protein 1 (4E-BP1) suppresses translation initiation. The absence of 4E-BP1 drastically reduces the amount of adipose tissue in mice. To address the role of 4E-BP1 in adipocyte differentiation, we characterized 4E-BP1(-/-) mice in this study. The lack of 4E-BP1 decreased the amount of white adipose tissue and increased the amount of brown adipose tissue. In 4E-BP1(-/-) MEF cells, PPARγ coactivator 1 alpha (PGC-1α) expression increased and exogenous 4E-BP1 expression suppressed PGC-1α expression. The level of 4E-BP1 expression was higher in white adipocytes than in brown adipocytes and showed significantly greater up-regulation in white adipocytes than in brown adipocytes during preadipocyte differentiation into mature adipocytes. The amount of PGC-1α was consistently higher in HB cells (a brown preadipocyte cell line) than in HW cells (a white preadipocyte cell line) during differentiation. Moreover, the ectopic over-expression of 4E-BP1 suppressed PGC-1α expression in white adipocytes, but not in brown adipocytes. Thus, the results of our study indicate that 4E-BP1 may suppress brown adipocyte differentiation and PGC-1α expression in white adipose tissues. © 2013 The Authors Genes to Cells © 2013 by the Molecular Biology Society of Japan and Wiley Publishing Asia Pty Ltd.

Endometrial seedlings. A survival instinct? Immunomodulation and its role in the pathophysiology of endometriosis.

PubMed

Portelli, M; Pollacco, J; Sacco, K; Schembri-Wismayer, P; Calleja-Agius, J

2011-12-01

Endometriosis occurs when ectopic cells from the endometrium implant within the peritoneum. It is considered as a disease of multifactorial aetiology and affects 7-10% of women of reproductive age worldwide. In endometriosis, the immune system is thought to be dysfunctional and various studies have shown cytokine imbalance. Commonly upregulated cytokines include Tumour necrosis factor-alpha, interferon gamma and interleukin-10. Through analysis of the molecular makeup of the peritoneal fluid, a change is shown to occur, conferring resistance from macrophages and lymphocytes to endometrial cells. This is possibly due to a reduced Inter-cellular adhesion molecule-1 synthesis. Survival of ectopic endometrial cells also arises through the expression of human leukocyte antigens. Apart from the survival of ectopic/eutopic cells in endometriosis, there is marked cellular proliferation, which has also been attributed to a change in the expression of proteins such as Bcl-2-Associated X protein, B-cell lymphoma-2 protein, transforming growth factor-beta and the enzyme aromatase. Danazol and aromatase inhibitors modulate the immune system, thus allowing partial restoration of cytokine levels. Pharmacogenomics may be the way forward in developing novel treatment modalities for endometriosis.

Lrp5/6 are required for cerebellar development and for suppressing TH expression in Purkinje cells via β-catenin.

PubMed

Huang, Ying; Zhang, Qiong; Song, Ning-Ning; Zhang, Lei; Sun, Yu-Ling; Hu, Ling; Chen, Jia-Ying; Zhu, Weidong; Li, Jue; Ding, Yu-Qiang

2016-01-15

The cerebellum is responsible for coordinating motor functions and has a unique laminated architecture. Purkinje cells are inhibitory neurons and represent the only output from the cerebellar cortex. Tyrosine hydroxylase (TH) is the key enzyme for the synthesis of catecholamines, including dopamine and noradrenaline, and it is normally not expressed in cerebellar neurons. We report here that the low-density lipoprotein receptors (Lrp) 5 and 6, Wnt co-receptors, are required for the development of the cerebellum and for suppressing ectopic TH expression in Purkinje cells. Simultaneous inactivation of Lrp 5 and 6 by Nestin-Cre results in defective lamination and foliation of the cerebellum during postnatal development. Surprisingly, TH is ectopically expressed by Purkinje cells, although they still keep its other neurochemical characteristics. These phenotypes are also observed in the cerebellum of GFAP-Cre;β-catenin(flox/flox) mice, and AAV2-Cre-mediated gene deletion leads to ectopic TH expression in Purkinje cells of β-catenin(flox/flox) mice as well. Our results revealed a new role of the canonical Lrp5/6-β-catenin pathway in regulating the morphogenesis of the cerebellum during postnatal development.

Periostin, a matrix specific protein, is associated with proliferation and invasion of pancreatic cancer.

PubMed

Ben, Qi-Wen; Jin, Xiao-Long; Liu, Jun; Cai, Xia; Yuan, Fei; Yuan, Yao-Zong

2011-03-01

Overexpression of periostin is present in various malignant tumors and correlates with disease progression. However, its clinicopathological significance in pancreatic cancer is currently not known. Expression of periostin was analyzed by RT-PCR and western blotting in pancreatic cancers and cell lines. Using immunohistochemistry, expression of periostin in pancreatic cancers was evaluated according to factors influencing overall survival with Kaplan-Meier analysis. Ectopic expression of periostin was used to examine the effects of periostin on proliferation and invasiveness of pancreatic cancer cells in vitro. There was no detectable periostin mRNA and protein expression in the 4 pancreatic cell lines. Expression of periostin was found to be up-regulated in pancreatic cancer compared to the adjacent tumor free (TF) tissues by western blotting. The positive ratio of periostin expression in the neoplastic stroma was significantly correlated with the depth of invasion (p=0.007) and lymph node metastasis (p=0.027). Survival analysis showed that stromal or epithelium expression of periostin was associated with poor survival (p=0.035, p=0.022, log-rank test, respectively). In vitro studies showed that periostin was able to promote proliferation and invasiveness of pancreatic cancer cells. These results suggest that periostin may be involved in the progression and invasion of pancreatic cancer.

The Mediator Kinase Module Restrains Epidermal Growth Factor Receptor Signaling and Represses Vulval Cell Fate Specification in Caenorhabditis elegans.

PubMed

Grants, Jennifer M; Ying, Lisa T L; Yoda, Akinori; You, Charlotte C; Okano, Hideyuki; Sawa, Hitoshi; Taubert, Stefan

2016-02-01

Cell signaling pathways that control proliferation and determine cell fates are tightly regulated to prevent developmental anomalies and cancer. Transcription factors and coregulators are important effectors of signaling pathway output, as they regulate downstream gene programs. In Caenorhabditis elegans, several subunits of the Mediator transcriptional coregulator complex promote or inhibit vulva development, but pertinent mechanisms are poorly defined. Here, we show that Mediator's dissociable cyclin dependent kinase 8 (CDK8) module (CKM), consisting of cdk-8, cic-1/Cyclin C, mdt-12/dpy-22, and mdt-13/let-19, is required to inhibit ectopic vulval cell fates downstream of the epidermal growth factor receptor (EGFR)-Ras-extracellular signal-regulated kinase (ERK) pathway. cdk-8 inhibits ectopic vulva formation by acting downstream of mpk-1/ERK, cell autonomously in vulval cells, and in a kinase-dependent manner. We also provide evidence that the CKM acts as a corepressor for the Ets-family transcription factor LIN-1, as cdk-8 promotes transcriptional repression by LIN-1. In addition, we find that CKM mutation alters Mediator subunit requirements in vulva development: the mdt-23/sur-2 subunit, which is required for vulva development in wild-type worms, is dispensable for ectopic vulva formation in CKM mutants, which instead display hallmarks of unrestrained Mediator tail module activity. We propose a model whereby the CKM controls EGFR-Ras-ERK transcriptional output by corepressing LIN-1 and by fine tuning Mediator specificity, thus balancing transcriptional repression vs. activation in a critical developmental signaling pathway. Collectively, these data offer an explanation for CKM repression of EGFR signaling output and ectopic vulva formation and provide the first evidence of Mediator CKM-tail module subunit crosstalk in animals. Copyright © 2016 by the Genetics Society of America.

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

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

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

The Inhibition of the Highly Expressed Mir-221 and Mir-222 Impairs the Growth of Prostate Carcinoma Xenografts in Mice

PubMed Central

Mercatelli, Neri; Coppola, Valeria; Bonci, Desirée; Miele, Francesca; Costantini, Arianna; Guadagnoli, Marco; Bonanno, Elena; Muto, Giovanni; Frajese, Giovanni Vanni; De Maria, Ruggero; Spagnoli, Luigi Giusto; Farace, Maria Giulia; Ciafrè, Silvia Anna

2008-01-01

Background MiR-221 and miR-222 are two highly homologous microRNAs whose upregulation has been recently described in several types of human tumors, for some of which their oncogenic role was explained by the discovery of their target p27, a key cell cycle regulator. We previously showed this regulatory relationship in prostate carcinoma cell lines in vitro, underlying the role of miR-221/222 as inducers of proliferation and tumorigenicity. Methodology/Principal Findings Here we describe a number of in vivo approaches confirming our previous data. The ectopic overexpression of miR-221 is able, per se, to confer a high growth advantage to LNCaP-derived tumors in SCID mice. Consistently, the anti-miR-221/222 antagomir treatment of established subcutaneous tumors derived from the highly aggressive PC3 cell line, naturally expressing high levels of miR-221/222, reduces tumor growth by increasing intratumoral p27 amount; this effect is long lasting, as it is detectable as long as 25 days after the treatment. Furthermore, we provide evidence in favour of a clinical relevance of the role of miR-221/222 in prostate carcinoma, by showing their general upregulation in patient-derived primary cell lines, where we find a significant inverse correlation with p27 expression. Conclusions/Significance These findings suggest that modulating miR-221/222 levels may have a therapeutic potential in prostate carcinoma. PMID:19107213

Frequent Attenuation of the WWOX Tumor Suppressor in Osteosarcoma is Associated with Increased Tumorigenicity and Aberrant RUNX2 Expression

PubMed Central

Kurek, Kyle; Del Mare, Sara; Salah, Zaidoun; Abdeen, Suhaib; Sadiq, Hussain; Lee, Sukhee; Gaudio, Eugenio; Zanesi, Nicola; Jones, Kevin B.; DeYoung, Barry; Amir, Gail; Gebhardt, Mark; Warman, Matthew; Stein, Gary S.; Stein, Janet L.; Lian, Jane B.; Aqeilan, Rami I.

2011-01-01

The WW domain-containing oxidoreductase (WWOX) is a tumor suppressor that is deleted or attenuated in most human tumors. Wwox-deficient mice develop osteosarcoma (OS), an aggressive bone tumor with poor prognosis that often metastasizes to lung. On the basis of these observations, we examined the status of WWOX in human OS specimens and cell lines. In human OS clinical samples, WWOX expression was absent or reduced in 58% of tumors examined (P< 0.0001). Compared to the primary tumors, WWOX levels frequently increased in tumors resected following chemotherapy. In contrast, tumor metastases to lung often exhibited reduced WWOX levels, relative to the primary tumor. In human OS cell lines having reduced WWOX expression, ectopic expression of WWOX inhibited proliferation and attenuated invasion in vitro, and suppressed tumorgenicity in nude mice. Expression of WWOX was associated with reduced RUNX2 expression in OS cell lines, whereas Runx2 levels were elevated in femurs of Wwox-deficient mice. Furthermore, WWOX reconstitution in HOS cells was associated with downregulation of RUNX2 levels and RUNX2 target genes, consistent with the ability of WWOX to suppress RUNX2 transactivation activity. In clinical samples, RUNX2 was expressed in the majority of primary tumors and undetectable in most tumors resected following chemotherapy, whereas most metastases were RUNX2 positive. Our results deepen the evidence of a tumor suppressor role for WWOX in OS, furthering its prognostic and therapeutic significance in this disease. PMID:20530675

FXR controls the tumor suppressor NDRG2 and FXR agonists reduce liver tumor growth and metastasis in an orthotopic mouse xenograft model.

PubMed

Deuschle, Ulrich; Schüler, Julia; Schulz, Andreas; Schlüter, Thomas; Kinzel, Olaf; Abel, Ulrich; Kremoser, Claus

2012-01-01

The farnesoid X receptor (FXR) is expressed predominantly in tissues exposed to high levels of bile acids and controls bile acid and lipid homeostasis. FXR(-/-) mice develop hepatocellular carcinoma (HCC) and show an increased prevalence for intestinal malignancies, suggesting a role of FXR as a tumor suppressor in enterohepatic tissues. The N-myc downstream-regulated gene 2 (NDRG2) has been recognized as a tumor suppressor gene, which is downregulated in human hepatocellular carcinoma, colorectal carcinoma and many other malignancies.We show reduced NDRG2 mRNA in livers of FXR(-/-) mice compared to wild type mice and both, FXR and NDRG2 mRNAs, are reduced in human HCC compared to normal liver. Gene reporter assays and Chromatin Immunoprecipitation data support that FXR directly controls NDRG2 transcription via IR1-type element(s) identified in the first introns of the human, mouse and rat NDRG2 genes. NDRG2 mRNA was induced by non-steroidal FXR agonists in livers of mice and the magnitude of induction of NDRG2 mRNA in three different human hepatoma cell lines was increased when ectopically expressing human FXR. Growth and metastasis of SK-Hep-1 cells was strongly reduced by non-steroidal FXR agonists in an orthotopic liver xenograft tumor model. Ectopic expression of FXR in SK-Hep1 cells reduced tumor growth and metastasis potential of corresponding cells and increased the anti-tumor efficacy of FXR agonists, which may be partly mediated via increased NDRG2 expression. FXR agonists may show a potential in the prevention and/or treatment of human hepatocellular carcinoma, a devastating malignancy with increasing prevalence and limited therapeutic options.

The neural stem cell fate determinant TLX promotes tumorigenesis and genesis of cells resembling glioma stem cells.

PubMed

Park, Hyo-Jung; Kim, Jun-Kyum; Jeon, Hye-Min; Oh, Se-Yeong; Kim, Sung-Hak; Nam, Do-Hyun; Kim, Hyunggee

2010-11-01

A growing body of evidence indicates that deregulation of stem cell fate determinants is a hallmark of many types of malignancies. The neural stem cell fate determinant TLX plays a pivotal role in neurogenesis in the adult brain by maintaining neural stem cells. Here, we report a tumorigenic role of TLX in brain tumor initiation and progression. Increased TLX expression was observed in a number of glioma cells and glioma stem cells, and correlated with poor survival of patients with gliomas. Ectopic expression of TLX in the U87MG glioma cell line and Ink4a/Arf-deficient mouse astrocytes (Ink4a/Arf(-/-) astrocytes) induced cell proliferation with a concomitant increase in cyclin D expression, and accelerated foci formation in soft agar and tumor formation in in vivo transplantation assays. Furthermore, overexpression of TLX in Ink4a/Arf(-/-) astrocytes inhibited cell migration and invasion and promoted neurosphere formation and Nestin expression, which are hallmark characteristics of glioma stem cells, under stem cell culture conditions. Our results indicate that TLX is involved in glioma stem cell genesis and represents a potential therapeutic target for this type of malignancy.

Regulation of EGF receptor signaling by the MARVEL domain-containing protein CKLFSF8.

PubMed

Jin, Caining; Ding, Peiguo; Wang, Ying; Ma, Dalong

2005-11-21

It is known that chemokine-like factor superfamily 8 (CKLFSF8), a member of the CKLF superfamily, has four putative transmembrane regions and a MARVEL domain. Its structure is similar to TM4SF11 (plasmolipin) and widely distributed in normal tissue. However, its function is not yet known. We show here that CKLFSF8 is associated with the epidermal growth factor receptor (EGFR) and that ectopic expression of CKLFSF8 in several cell lines suppresses EGF-induced cell proliferation, whereas knockdown of CKLFSF8 by siRNA promotes cell proliferation. In cells overexpressing CKLFSF8, the initial activation of EGFR was not affected, but subsequent desensitization of EGF-induced signaling occurred rapidly. This attenuation was correlated with an increased rate of receptor endocytosis. In contrast, knockdown of CKLFSF8 by siCKLFSF8 delayed EGFR endocytosis. These results identify CKLFSF8 as a novel regulator of EGF-induced signaling and indicate that the association of EGFR with four transmembrane proteins is critical for EGFR desensitization.

Thymocyte Maturation Is Regulated by the Activity of the Helix-Loop-Helix Protein, E47

PubMed Central

Bain, Gretchen; Quong, Melanie W.; Soloff, Rachel S.; Hedrick, Stephen M.; Murre, Cornelis

1999-01-01

The E2A proteins, E12 and E47, are required for progression through multiple developmental pathways, including early B and T lymphopoiesis. Here, we provide in vitro and in vivo evidence demonstrating that E47 activity regulates double-positive thymocyte maturation. In the absence of E47 activity, positive selection of both major histocompatibility complex (MHC) class I– and class II–restricted T cell receptors (TCRs) is perturbed. Additionally, development of CD8 lineage T cells in an MHC class I–restricted TCR transgenic background is sensitive to the dosage of E47. Mice deficient for E47 display an increase in production of mature CD4 and CD8 lineage T cells. Furthermore, ectopic expression of an E2A inhibitor helix-loop-helix protein, Id3, promotes the in vitro differentiation of an immature T cell line. These results demonstrate that E2A functions as a regulator of thymocyte positive selection. PMID:10587351

Profilin1 activity in cerebellar granule neurons is required for radial migration in vivo

PubMed Central

Kullmann, Jan A; Wickertsheim, Ines; Minnerup, Lara; Costell, Mercedes; Friauf, Eckhard; Rust, Marco B

2015-01-01

Neuron migration defects are an important aspect of human neuropathies. The underlying molecular mechanisms of such migration defects are largely unknown. Actin dynamics has been recognized as an important determinant of neuronal migration, and we recently found that the actin-binding protein profilin1 is relevant for radial migration of cerebellar granule neurons (CGN). As the exploited brain-specific mutants lacked profilin1 in both neurons and glial cells, it remained unknown whether profilin1 activity in CGN is relevant for CGN migration in vivo. To test this, we capitalized on a transgenic mouse line that expresses a tamoxifen-inducible Cre variant in CGN, but no other cerebellar cell type. In these profilin1 mutants, the cell density was elevated in the molecular layer, and ectopic CGN occurred. Moreover, 5-bromo-2′-deoxyuridine tracing experiments revealed impaired CGN radial migration. Hence, our data demonstrate the cell autonomous role of profilin1 activity in CGN for radial migration. PMID:25495756

Autophagy is activated in colorectal cancer cells and contributes to the tolerance to nutrient deprivation.

PubMed

Sato, Kazunori; Tsuchihara, Katsuya; Fujii, Satoshi; Sugiyama, Masanori; Goya, Tomoyuki; Atomi, Yutaka; Ueno, Takashi; Ochiai, Atsushi; Esumi, Hiroyasu

2007-10-15

Several types of cancer cells, including colorectal cancer-derived cell lines, show austerity, the resistance to nutrient starvation, but exactly how cancer cells obtain energy sources under conditions in which their external nutrient supply is extremely limited remains to be clarified. Because autophagy is a catabolic process by which cells supply amino acids from self-digested organelles, cancer cells are likely to use autophagy to obtain amino acids as alternative energy sources. Amino acid deprivation-induced autophagy was assessed in DLD-1 and other colorectal cancer-derived cell lines. The autophagosome-incorporated LC3-II protein level increased after treatment with a combination of autolysosome inhibitors, which interferes with the consumption of autophagosomes. Autophagosome formation was also morphologically confirmed using ectopically expressed green fluorescent protein-LC3 fusion proteins in DLD-1 and SW480 cells. These data suggest that autophagosomes were actively produced and promptly consumed in colorectal cancer cells under nutrient starvation. Autolysosome inhibitors and 3-methyl adenine, which suppresses autophagosome formation, remarkably enhanced apoptosis under amino acid-deprived and glucose-deprived condition. Similar results were obtained in the cells with decreased ATG7 level by the RNA interference. These data suggest that autophagy is pivotal for the survival of colorectal cancer cells that have acquired austerity. Furthermore, autophagosome formation was seen only in the tumor cells but not in the adjacent noncancerous epithelial cells of colorectal cancer specimens. Taken together, autophagy is activated in colorectal cancers in vitro and in vivo, and autophagy may contribute to the survival of the cancer cells in their microenvironment.

MicroRNA-340 suppresses osteosarcoma tumor growth and metastasis by directly targeting ROCK1

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

Zhou, Xin; Wei, Min; Wang, Wei, E-mail: rjwangwei@126.com

2013-08-09

Highlights: •miR-340 is downregulated in OS cell lines and tissues. •miR-340 suppresses OS cell proliferation, migration and invasion. •miR-340 suppresses tumor growth and metastasis of OS cells in nude mice. •ROCK1 is a target gene of miR-340. •ROCK1 is involved in miR-340-induced suppression of OS cell proliferation, migration and invasion. -- Abstract: MicroRNAs (miRNAs) play key roles in cancer development and progression. In the present study, we investigated the role of miR-340 in the progression and metastasis of osteosarcoma (OS). Our results showed that miR-340 was frequently downregulated in OS tumors and cell lines. Overexpression of miR-340 in OS cellmore » lines significantly inhibited cell proliferation, migration, and invasion in vitro, and tumor growth and metastasis in a xenograft mouse model. ROCK1 was identified as a target of miR-340, and ectopic expression of miR-340 downregulated ROCK1 by direct binding to its 3′ untranslated region. siRNA-mediated silencing of ROCK1 phenocopied the effects of miR-340 overexpression, whereas restoration of ROCK1 in miR-340-overexpressing OS cells reversed the suppressive effects of miR-340. Together, these findings indicate that miR-340 acts as a tumor suppressor and its downregulation in tumor tissues may contribute to the progression and metastasis of OS through a mechanism involving ROCK1, suggesting miR-340 as a potential new diagnostic and therapeutic target for the treatment of OS.« less

miR-137 inhibits renal cell carcinoma growth in vitro and in vivo

PubMed Central

ZHANG, HONGXIA; LI, HONGJUN

2016-01-01

MicroRNA (miR)-137 has been reported to be underexpressed and involved in various cell processes and to have antitumor effects in a range of tumors, but so far not in renal cell carcinoma (RCC). The aim of the present study was to investigate the clinical significance and role of miR-137 in RCC. The expression levels of miR-137 were determined by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) in 50 cases of paired RCC tissues and adjacent normal tissues, and in RCC cell lines. The role of miR-137 in the growth and survival of RCC cells was assessed with several in vitro approaches and in nude mice models. The results of the RT-qPCR showed that the miR-137 expression was downregulated in the RCC tissues and cell lines. The in vitro assay showed that ectopic expression of miR-137 robustly impaired RCC cell proliferation, migratory and invasive properties, and increased the induction of cell apoptosis properties. The in vivo assay demonstrated that enforced miR-137 suppressed tumor growth in xenograft nude mice models. In addition, miR-137 was indicated to inhibit the activation of phosphoinositide 3 kinase/protein kinase B signal pathway, which contributes to the inhibition of RCC growth. These findings indicate that miR-137 functions as tumor suppressor in RCC, suggesting that miR-137 may be a potential therapeutic target for RCC. PMID:27347205

Ectopic expression of necdin induces differentiation of mouse neuroblastoma cells.

PubMed

Kobayashi, Masakatsu; Taniura, Hideo; Yoshikawa, Kazuaki

2002-11-01

Necdin is expressed predominantly in postmitotic neurons, and ectopic expression of this protein strongly suppresses cell growth. Necdin has been implicated in the pathogenesis of Prader-Willi syndrome, a human neurodevelopmental disorder associated with genomic imprinting. Here we demonstrate that ectopic expression of necdin induces a neuronal phenotype in neuroblastoma cells. Necdin was undetectable in mouse neuroblastoma N1E-115 cells under undifferentiated and differentiated conditions. N1E-115 cells transfected with necdin cDNA showed morphological differentiation such as neurite outgrowth and expression of the synaptic marker proteins synaptotagmin and synaptophysin. In addition, Western blot analysis of the retinoblastoma protein (Rb) family members Rb, p130, and p107 revealed that necdin cDNA transfectants contained an increased level of p130 and a reduced level of p107, a pattern seen in differentiated G(0) cells. The transcription factors E2F1 and E2F4 physically interacted with necdin via their carboxyl-terminal transactivation domains, but only E2F1 abrogated necdin-induced growth arrest and neurite outgrowth of neuroblastoma cells. Overexpression of E2F1 in differentiated N1E-115 cells induced apoptosis, which was antagonized by co-expression of necdin. These results suggest that necdin promotes the differentiation and survival of neurons through its antagonistic interactions with E2F1.

Endometrial cysteine-rich secretory protein 3 is inhibited by human chorionic gonadotrophin, and is increased in the decidua of tubal ectopic pregnancy.

PubMed

Horne, A W; Duncan, W C; King, A E; Burgess, S; Lourenco, P C; Cornes, P; Ghazal, P; Williams, A R; Udby, L; Critchley, H O D

2009-05-01

Ectopic pregnancy (EP) remains a considerable cause of morbidity and occasional mortality. Currently, there is no reliable test to differentiate ectopic from intrauterine gestation. We have previously used array technology to demonstrate that differences in gene expression in decidualized endometrium from women with ectopic and intrauterine gestations could be used to identify candidate diagnostic biomarkers for EP. The aim of this study was to further investigate the decidual gene with the highest fold increase in EP, cysteine-rich secretory protein-3 (CRISP-3). Decidualized endometrium from gestation-matched women undergoing surgical termination of pregnancy (n = 8), evacuation of uterus for miscarriage (n = 6) and surgery for EP (n = 11) was subjected to quantitative RT-PCR, morphological assessment, immunohistochemistry and western blot analysis. Sera were analysed for progesterone and human chorionic gonadotrophin (hCG) levels. Immortalized endometrial epithelial cells were cultured with physiological concentrations of hCG. CRISP-3 mRNA and protein expression were greater in endometrium from ectopic when compared with intrauterine pregnancies (P < 0.05). CRISP-3 protein was localized to epithelium and granulocytes of endometrium. CRISP-3 serum concentrations were not different in women with ectopic compared with intrauterine pregnancies. CRISP-3 expression in endometrium was not related to the degree of decidualization or to serum progesterone levels. Endometrial CRISP-3 expression was inversely proportional to serum hCG concentrations (P < 0.001). Stimulation of endometrial epithelial cells with hCG in vitro caused a reduction in CRISP-3 expression (P < 0.01). The measurement of CRISP-3 in endometrium could provide an additional tool in the diagnosis of failing early pregnancy of unknown location. The absence of a local reduction in expression of CRISP-3 in decidualized endometrium of women with EP may be due to reduced exposure to hCG due to the ectopic location of the trophoblast.

Ectopic norrin induces growth of ocular capillaries and restores normal retinal angiogenesis in Norrie disease mutant mice.

PubMed

Ohlmann, Andreas; Scholz, Michael; Goldwich, Andreas; Chauhan, Bharesh K; Hudl, Kristiane; Ohlmann, Anne V; Zrenner, Eberhart; Berger, Wolfgang; Cvekl, Ales; Seeliger, Mathias W; Tamm, Ernst R

2005-02-16

Norrie disease is an X-linked retinal dysplasia that presents with congenital blindness, sensorineural deafness, and mental retardation. Norrin, the protein product of the Norrie disease gene (NDP), is a secreted protein of unknown biochemical function. Norrie disease (Ndp(y/-)) mutant mice that are deficient in norrin develop blindness, show a distinct failure in retinal angiogenesis, and completely lack the deep capillary layers of the retina. We show here that the transgenic expression of ectopic norrin under control of a lens-specific promoter restores the formation of a normal retinal vascular network in Ndp(y/-) mutant mice. The improvement in structure correlates with restoration of neuronal function in the retina. In addition, lenses of transgenic mice with ectopic expression of norrin show significantly more capillaries in the hyaloid vasculature that surrounds the lens during development. In vitro, lenses of transgenic mice in coculture with microvascular endothelial cells induce proliferation of the cells. Transgenic mice with ectopic expression of norrin show more bromodeoxyuridine-labeled retinal progenitor cells at embryonic day 14.5 and thicker retinas at postnatal life than wild-type littermates, indicating a putative direct neurotrophic effect of norrin. These data provide direct evidence that norrin induces growth of ocular capillaries and that pharmacologic modulation of norrin might be used for treatment of the vascular abnormalities associated with Norrie disease or other vascular disorders of the retina.

Star-PAP, a poly(A) polymerase, functions as a tumor suppressor in an orthotopic human breast cancer model.

PubMed

Yu, C; Gong, Y; Zhou, H; Wang, M; Kong, L; Liu, J; An, T; Zhu, H; Li, Y

2017-02-02

Star-PAP is a noncanonical poly(A) polymerase and required for the expression of a select set of mRNAs. However, the pathological role of Star-PAP in cancer largely remains unknown. In this study, we observed decreased expression of Star-PAP in breast cancer cell lines and tissues. Ectopic Star-PAP expression inhibited proliferation as well as colony-forming ability of breast cancer cells. In breast cancer patients, high levels of Star-PAP correlated with an improved prognosis. Moreover, by regulating the expression of BIK (BCL2-interacting killer), Star-PAP induced apoptosis of breast cancer cells through the mitochondrial pathway. The growth of breast cancer xenografts in NOD/SCID mice was also inhibited by the doxycycline-induced Star-PAP overexpression. Furthermore, Star-PAP sensitized breast cancer cells to chemotherapy drugs both in vitro and in vivo. In mammary epithelial cells, Star-PAP knockdown partially transformed these cells and induced them to undergo epithelial-mesenchymal transition (EMT). These findings suggested that Star-PAP possesses tumor-suppressing activity and can be a valuable target for developing new cancer therapeutic strategies.

MiR-135 post-transcriptionally regulates FOXO1 expression and promotes cell proliferation in human malignant melanoma cells.

PubMed

Ren, Jian-Wen; Li, Zhang-Jun; Tu, Chen

2015-01-01

Malignant melanoma is the deadliest form of all skin cancers. Recently, microRNAs (miRNAs) are small, non-coding RNAs that regulate gene expression by targeted repression of transcription and translation and play essential roles during cancer development. Our study showed that miR-135a is upregulated in malignant melanoma tissues and cell lines by using Real-time PCR assay. Enforced expression of miR-135a in malignant melanoma cells promotes cell proliferation, tumorigenicity, and cell cycle progression, whereas inhibition of miR-135a reverses the function. Additionally, we demonstrated FOXO1 is a direct target of miR-135a and transcriptionally down-regulated by miR-135a. Ectopic expression of miR-135a led to downregulation of the FOXO1 protein, resulting in upregulation of Cyclin D1, and downregulation of P21(Cip1) and P27(Kip1) through AKT pathway. Our findings suggested that miR-135a represents a potential onco-miRNA and plays an important role in malignant melanoma progression by suppressing FOXO1 expression.

MUC4 modulates human glioblastoma cell proliferation and invasion by upregulating EGFR expression.

PubMed

Li, Weihua; Wu, Chunming; Yao, Yiqun; Dong, Bin; Wei, Zhenqing; Lv, Xiupeng; Zhang, Jian; Xu, Yinghui

2014-04-30

Glioblastoma (GBM), the most common primary brain tumor, is the leading cause of deaths related to tumors in the central nervous system. The prognosis of GBM patients is currently poor, and the mechanisms underlying GBM genesis remain unclear. The expression of MUC4, a high-molecular-weight and highly glycosylated protein, has been studied in many cancers. However, information on MUC4 expression in GBM is limited. In this study, we found that MUC4 was overexpressed in GBM cell lines and tissues. The proliferation and invasive potential of GBM cells were significantly increased by the ectopic expression of MUC4. By contrast, RNA interference targeting MUC4 in GBM cells significantly decreased the proliferation and invasive potential of GBM cells. We also found that the expression of epidermal growth factor receptor (EGFR) was modulated by MUC4. EGFR inhibition by siRNA reversed the MUC4-induced proliferation and invasion. These results indicated that MUC4 expression in GBM was important in GBM cell proliferation and invasion, which may be partly associated with EGFR overexpression. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Human papillomavirus E6 protein enriches the CD55(+) population in cervical cancer cells, promoting radioresistance and cancer aggressiveness.

PubMed

Leung, Thomas Ho-Yin; Tang, Hermit Wai-Man; Siu, Michelle Kwan-Yee; Chan, David Wai; Chan, Karen Kar-Loen; Cheung, Annie Nga-Yin; Ngan, Hextan Yuen-Sheung

2018-02-01

Accumulating evidence indicates that the human papillomavirus (HPV) E6 protein plays a crucial role in the development of cervical cancer. Subpopulations of cells that reside within tumours are responsible for tumour resistance to cancer therapy and recurrence. However, the identity of such cells residing in cervical cancer and their relationship with the HPV-E6 protein have not been identified. Here, we isolated sphere-forming cells, which showed self-renewal ability, from primary cervical tumours. Gene expression profiling revealed that cluster of differentiation (CD) 55 was upregulated in primary cervical cancer sphere cells. Flow-cytometric analysis detected abundant CD55(+) populations among a panel of HPV-positive cervical cancer cell lines, whereas few CD55(+) cells were found in HPV-negative cervical cancer and normal cervical epithelial cell lines. The CD55(+) subpopulation isolated from the C33A cell line showed significant sphere-forming ability and enhanced tumourigenicity, cell migration, and radioresistance. In contrast, the suppression of CD55 in HPV-positive CaSki cells inhibited tumourigenicity both in vitro and in vivo, and sensitized cells to radiation treatment. In addition, ectopic expression of the HPV-E6 protein in HPV-negative cervical cancer cells dramatically enriched the CD55(+) subpopulation. CRISPR/Cas9 knockout of CD55 in an HPV-E6-overexpressing stable clone abolished the tumourigenic effects of the HPV-E6 protein. Taken together, our data suggest that HPV-E6 protein expression enriches the CD55(+) population, which contributes to tumourigenicity and radioresistance in cervical cancer cells. Targeting CD55 via CRISPR/Cas9 may represent a novel avenue for developing new strategies and effective therapies for the treatment of cervical cancer. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

The Receptor Tyrosine Kinase EphA2 Is a Direct Target Gene of Hypermethylated in Cancer 1 (HIC1)*

PubMed Central

Foveau, Bénédicte; Boulay, Gaylor; Pinte, Sébastien; Van Rechem, Capucine; Rood, Brian R.; Leprince, Dominique

2012-01-01

The tumor suppressor gene hypermethylated in cancer 1 (HIC1), which encodes a transcriptional repressor, is epigenetically silenced in many human tumors. Here, we show that ectopic expression of HIC1 in the highly malignant MDA-MB-231 breast cancer cell line severely impairs cell proliferation, migration, and invasion in vitro. In parallel, infection of breast cancer cell lines with a retrovirus expressing HIC1 also induces decreased mRNA and protein expression of the tyrosine kinase receptor EphA2. Moreover, chromatin immunoprecipitation (ChIP) and sequential ChIP experiments demonstrate that endogenous HIC1 proteins are bound, together with the MTA1 corepressor, to the EphA2 promoter in WI38 cells. Taken together, our results identify EphA2 as a new direct target gene of HIC1. Finally, we observe that inactivation of endogenous HIC1 through RNA interference in normal breast epithelial cells results in the up-regulation of EphA2 and is correlated with increased cellular migration. To conclude, our results involve the tumor suppressor HIC1 in the transcriptional regulation of the tyrosine kinase receptor EphA2, whose ligand ephrin-A1 is also a HIC1 target gene. Thus, loss of the regulation of this Eph pathway through HIC1 epigenetic silencing could be an important mechanism in the pathogenesis of epithelial cancers. PMID:22184117

[Ectopic breast fibroadenoma. Case report].

PubMed

Senatore, G; Zanotti, S; Cambrini, P; Montroni, I; Pellegrini, A; Montanari, E; Santini, D; Taffurelli, M

2010-03-01

Among the rare anomalies of the breast development, polythelia is the most common, between 1% and 5% of women and men present supernumerary nipples. Polymastia, usually presenting as ectopic breast tissue without areola-nipple complex, is seen mostly along the milk line, extending from the axilla to the pubic region. Ectopic breast tissue is functionally analogous to mammary gland and it is subjected to the same alterations and diseases, whether benign or malignant, that affect normal breast tissue. We report the case of a 21 years-old female evaluated by the medical staff after founding a solid nodular mass by suspect axillary lymphadenopathy. Differential diagnosis with lymphoma is the major problem in these cases. The mass was removed and the intraoperative histological examination showed fibroadenoma in axillary supernumerary breast. Presence of ectopic breast tissue is a rare condition; development of benign mass or malignant degeneration is possible, but it is very unusual. In case of polymastia diagnosis is simple; in case of isolated nodule, without local inflammation or infection, there are greater difficulties. Ultrasonography is diagnostic in case of breast fibroadenoma, but it might be inadequate in ectopic localizations owing to the shortage of mammary tissue around the mass. Preoperative diagnosis is important to plan an adequate surgical treatment; lumpectomy is indicated in case of benign tissue; in case of malignancy, therapy is based on the standard treatment used for breast cancer (surgery, chemotherapy and radiation therapy).

Unus pro omnibus, omnes pro uno: A novel, evidence-based, unifying theory for the pathogenesis of endometriosis.

PubMed

Laganà, Antonio Simone; Vitale, Salvatore Giovanni; Salmeri, Francesca Maria; Triolo, Onofrio; Ban Frangež, Helena; Vrtačnik-Bokal, Eda; Stojanovska, Lily; Apostolopoulos, Vasso; Granese, Roberta; Sofo, Vincenza

2017-06-01

The theory of retrograde menstruation as aetiopathogenesis of endometriosis formulated by John Sampson in 1927 shows clear shortcomings: this does not explain why retrograde menstruation is a physiological process that affects 90% of women, while endometriosis occurs in only 10% of cases; it also does not explain the endometriotic foci distant from the pelvis, nor explains the cases of endometriosis in male patients. The immunological alterations of the peritoneal fluid explains the effects of disease, such as the inhibition of the physiological processes of cytolysis, but does not explain the cause. There is evidence to support the hypothesis that ectopic müllerian remnants of the endometrium, endocervix and endosalpinx are items from the genital ridge leaked during organogenesis. It is known that tissues derived from coelomatic epithelial and mesenchymal cells have the potential to metaplastically differentiate into epithelium and stroma. In addition, the phenotype of the ectopic endometrial cells is significantly different from those ectopic. There is scientific evidence that, during organogenesis, the genes of the Homeobox and Wingless family play a fundamental role in the differentiation of the ducts of Muller and development of the anatomical structure of the urogenital tract. We present here a hypothesis that deregulation of genes and the Wnt signaling pathway Wnt/β-catenin leads to aberrations and deregulation within the mesoderm, thus, may cause aberrant placement of stem cells. In addition, immune cells, adhesion molecules, extracellular matrix metalloproteinase and pro-inflammatory cytokines activate/alter peritoneal microenvironment, creating the conditions for differentiation, adhesion, proliferation and survival of ectopic endometrial cells. Copyright © 2017 Elsevier Ltd. All rights reserved.

Compartmentalization of the somite and myogenesis in chick embryos are influenced by wnt expression.

PubMed

Wagner, J; Schmidt, C; Nikowits, W; Christ, B

2000-12-01

Muscles of the body and bones of the axial skeleton derive from specialized regions of somites. Somite development is influenced by adjacent structures. In particular, the dorsal neural tube and the overlying ectoderm have been shown to be necessary for the induction of myogenic precursor cells in the dermomyotome. Members of the Wnt family of signaling molecules, which are expressed in the dorsal neural tube and the ectoderm, are postulated to be responsible for this process. It is shown here that ectopically implanted Wnt-1-, -3a-, and -4-expressing cells alter the process of somite compartmentalization in vivo. An enlarged dorsal compartment results from the implantation of Wnt-expressing cells ventrally between the neural tube/notochord and epithelial somites, at the expense of the ventral compartment, the sclerotome. Thus, ectopic Wnt expression is able to override the influence of ventralizing signals arising from notochord and floor plate. This shift of the border between the two compartments was identified by an increase in the domain of Pax-3 expression and a complete loss of Pax-1 expression in somites close to the ectopic Wnt signal. The expanded expression of MyoD and desmin provides evidence that it is the myotome which increases as a result of Wnt signaling. Paraxis expression is also drastically amplified after implantation of Wnt-expressing cells indicating that Wnts are involved in the formation and maintenance of somite epithelium and suggesting that Paraxis is activated through Wnt signaling pathways. Taken together these results suggest that ectopic Wnts disturb the normal balance of signaling molecules within the somite, resulting in an enhanced recruitment of somitic cells into the myogenic lineage. Copyright 2000 Academic Press.

CITED2 modulates estrogen receptor transcriptional activity in breast cancer cells

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

Lau, Wen Min; Doucet, Michele; Huang, David

2013-07-26

Highlights: •The effects of elevated CITED2 on ER function in breast cancer cells are examined. •CITED2 enhances cell growth in the absence of estrogen and presence of tamoxifen. •CITED2 functions as a transcriptional co-activator of ER in breast cancer cells. -- Abstract: Cbp/p300-interacting transactivator with Glu/Asp-rich carboxy-terminal domain 2 (CITED2) is a member of the CITED family of non-DNA binding transcriptional co-activators of the p300/CBP-mediated transcription complex. Previously, we identified CITED2 as being overexpressed in human breast tumors relative to normal mammary epithelium. Upon further investigation within the estrogen receptor (ER)-positive subset of these breast tumor samples, we found thatmore » CITED2 mRNA expression was elevated in those associated with poor survival. In light of this observation, we investigated the effect of elevated CITED2 levels on ER function. While ectopic overexpression of CITED2 in three ER-positive breast cancer cell lines (MCF-7, T47D, and CAMA-1) did not alter cell proliferation in complete media, growth was markedly enhanced in the absence of exogenous estrogen. Correspondingly, cells overexpressing CITED2 demonstrated reduced sensitivity to the growth inhibitory effects of the selective estrogen receptor modulator, 4-hydroxytamoxifen. Subsequent studies revealed that basal ER transcriptional activity was elevated in CITED2-overexpressing cells and was further increased upon the addition of estrogen. Similarly, basal and estrogen-induced expression of the ER-regulated genes trefoil factor 1 (TFF1) and progesterone receptor (PGR) was higher in cells overexpressing CITED2. Concordant with this observation, ChIP analysis revealed higher basal levels of CITED2 localized to the TFF-1 and PGR promoters in cells with ectopic overexpression of CITED2, and these levels were elevated further in response to estrogen stimulation. Taken together, these data indicate that CITED2 functions as a transcriptional co-activator of ER in breast cancer cells and that its increased expression in tumors may result in estrogen-independent ER activation, thereby reducing estrogen dependence and response to anti-estrogen therapy.« less

Hsa-miR-134 suppresses non-small cell lung cancer (NSCLC) development through down-regulation of CCND1

PubMed Central

Sun, Cheng-Cao; Li, Shu-Jun; Li, De-Jia

2016-01-01

Hsa-miRNA-134 (miR-134) has recently been discovered to have anticancer efficacy in different organs. However, the role of miR-134 on non-small cell lung cancer (NSCLC) is still ambiguous. In this study, we investigated the role of miR-134 on the development of NSCLC. The results indicated that miR-134 was significantly down-regulated in primary tumor tissues and very low levels were found in NSCLC cell lines. Ectopic expression of miR-134 in NSCLC cell lines significantly suppressed cell growth as evidenced by cell viability assay, colony formation assay and BrdU staining, through inhibition of cyclin D1, cyclin D2, CDK4 and up-regulation of p57(Kip2) and p21(Waf1/Cip1). In addition, miR-134 induced apoptosis, as indicated by concomitantly with up-regulation of key apoptosis protein cleaved caspase-3, and down-regulation of anti-apoptosis protein Bcl2. Moreover, miR-134 inhibited cellular migration and invasiveness through inhibition of matrix metalloproteinases (MMP)-7 and MMP-9. Further, oncogene CCND1 was revealed to be a putative target of miR-134, which was inversely correlated with miR-134 expression in NSCLC. Taken together, our results demonstrated that miR-134 played a pivotal role on NSCLC through inhibiting cell proliferation, migration, invasion, and promoting apoptosis by targeting oncogenic CCND1. PMID:27166267

Hsa-miR-326 targets CCND1 and inhibits non-small cell lung cancer development

PubMed Central

Li, Shujun; Yang, Cuili; Xi, Yongyong; Wang, Liang; Zhang, Feng; Fu, Yunfeng; Li, Dejia

2016-01-01

Hsa-miRNA-326 (miR-326) has recently been discovered having anticancer efficacy in different organs. However, the role of miR-326 on non-small cell lung cancer (NSCLC) is still ambiguous. In this study, we investigated the role of miR-326 on the development of NSCLC. The results indicated that miR-326 was significantly down-regulated in primary tumor tissues and very low levels were found in NSCLC cell lines. Ectopic expression of miR-326 in NSCLC cell lines significantly suppressed cell growth as evidenced by cell viability assay, colony formation assay and BrdU staining, through inhibition of cyclin D1, cyclin D2, CDK4 and up-regulation of p57(Kip2) and p21(Waf1/Cip1). In addition, miR-326 induced apoptosis, as indicated by concomitantly with up-regulation of key apoptosis protein cleaved caspase-3, and down-regulation of anti-apoptosis protein Bcl2. Moreover, miR-326 inhibited cellular migration and invasiveness through inhibition of matrix metalloproteinases (MMP)-7 and MMP-9. Further, oncogene CCND1 was revealed to be a putative target of miR-326, which was inversely correlated with miR-326 expression in NSCLC. Taken together, our results demonstrated that miR-326 played a pivotal role on NSCLC through inhibiting cell proliferation, migration, invasion, and promoting apoptosis by targeting oncogenic CCND1. PMID:26840018

Spatial distribution of osteoblast-specific transcription factor Cbfa1 and bone formation in atherosclerotic arteries.

PubMed

Bobryshev, Yuri V; Killingsworth, Murray C; Lord, Reginald S A

2008-08-01

The mechanisms of ectopic bone formation in arteries are poorly understood. Osteoblasts might originate either from stem cells that penetrate atherosclerotic plaques from the blood stream or from pluripotent mesenchymal cells that have remained in the arterial wall from embryonic stages of the development. We have examined the frequency of the expression and spatial distribution of osteoblast-specific factor-2/core binding factor-1 (Osf2/Cbfa1) in carotid and coronary arteries. Cbfa1-expressing cells were rarely observed but were found in all tissue specimens in the deep portions of atherosclerotic plaques under the necrotic cores. The deep portions of atherosclerotic plaques under the necrotic cores were characterized by the lack of capillaries of neovascularization. In contrast, plaque shoulders, which were enriched by plexuses of neovascularization, lacked Cbfa1-expressing cells. No bone formation was found in any of the 21 carotid plaques examined and ectopic bone was observed in only two of 12 coronary plaques. We speculate that the sparse invasion of sprouts of neovascularization into areas underlying the necrotic cores, where Cbfa1-expressing cells reside, might explain the rarity of events of ectopic bone formation in the arterial wall. This study has also revealed that Cbfa1-expressing cells contain alpha-smooth muscle actin and myofilaments, indicating their relationship with arterial smooth muscle cells.

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

Chertkov, J.L.; Drize, N.J.; Gurevitch, O.A.

Intravenously injected bone marrow cells do not participate in the regeneration of hemopoietic stromal progenitors in irradiated mice, nor in the curetted parts of the recipient's marrow. The hemopoietic stromal progenitors in allogeneic chimeras are of recipient origin. The adherent cell layer (ACL) of long-term cultures of allogeneic chimera bone marrow contains only recipient hemopoietic stromal progenitors. However, in ectopic hemopoietic foci produced by marrow implantation under the renal capsule and repopulated by the recipient hemopoietic cells after irradiation and reconstitution by syngeneic hemopoietic cells, the stromal progenitors were of implant donor origin, as were stromal progenitors of the ACLmore » in long-term cultures of hemopoietic cells from ectopic foci. Our results confirm that the stromal and hemopoietic progenitors differ in origin and that hemopoietic stromal progenitors are not transplantable by the intravenous route in mice.« less

Plasticity in adult cat visual cortex (area 17) following circumscribed monocular lesions of all retinal layers

PubMed Central

Calford, M B; Wang, C; Taglianetti, V; Waleszczyk, W J; Burke, W; Dreher, B

2000-01-01

In eight adult cats intense, sharply circumscribed, monocular laser lesions were used to remove all cellular layers of the retina. The extents of the retinal lesions were subsequently confirmed with counts of α-ganglion cells in retinal whole mounts; in some cases these revealed radial segmental degeneration of ganglion cells distal to the lesion.Two to 24 weeks later, area 17 (striate cortex; V1) was studied electrophysiologically in a standard anaesthetized, paralysed (artificially respired) preparation. Recording single- or multineurone activity revealed extensive topographical reorganization within the lesion projection zone (LPZ).Thus, with stimulation of the lesioned eye, about 75 % of single neurones in the LPZ had ‘ectopic’ visual discharge fields which were displaced to normal retina in the immediate vicinity of the lesion.The sizes of the ectopic discharge fields were not significantly different from the sizes of the normal discharge fields. Furthermore, binocular cells recorded from the LPZ, when stimulated via their ectopic receptive fields, exhibited orientation tuning and preferred stimulus velocities which were indistinguishable from those found when the cells were stimulated via the normal eye.However, the responses to stimuli presented via ectopic discharge fields were generally weaker (lower peak discharge rates) than those to presentations via normal discharge fields, and were characterized by a lower-than-normal upper velocity limit.Overall, the properties of the ectopic receptive fields indicate that cortical mechanisms rather than a retinal ‘periphery’ effect underlie the topographic reorganization of area 17 following monocular retinal lesions. PMID:10767137

Ectopic ERK Expression Induces Phenotypic Conversion of C10 Cells and Alters DNA Methyltransferase Expression

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

Sontag, Ryan L.; Weber, Thomas J.

2012-05-04

In some model systems constitutive extracellular signal regulated kinase (ERK) activation is sufficient to promote an oncogenic phenotype. Here we investigate whether constitutive ERK expression influences phenotypic conversion in murine C10 type II alveolar epithelial cells. C10 cells were stably transduced with an ERK1-green fluorescent protein (ERK1-GFP) chimera or empty vector and ectopic ERK expression was associated with the acquisition of soft agar focus-forming potential in late passage, but not early passage cells. Late passage ERK1-GFP cells exhibited a significant increase in the expression of DNA methyl transferases (DNMT1 and 3b) and a marked increase in sensitivity to 5-azacytidine (5-azaC)-mediatedmore » toxicity, relative to early passage ERK1-GFP cells and vector controls. The expression of xeroderma pigmentosum complementation group A (XPA) and DNA-dependent protein kinase catalytic subunit (DNA-PKcs) were significantly increased in late passage cells, suggesting enhanced DNA damage recognition and repair activity which we interpret as a reflection of genomic instability. Phospho-ERK levels were dramatically decreased in late passage ERK1-GFP cells, relative to early passage and vector controls, and phospho-ERK levels were restored by treatment with sodium orthovanadate, indicating a role for phosphatase activity in this response. Collectively these observations suggest that ectopic ERK expression promotes phenotypic conversion of C10 cells that is associated with latent effects on epigenetic programming and phosphatase activities.« less

Repression of c-Kit by p53 is mediated by miR-34 and is associated with reduced chemoresistance, migration and stemness

PubMed Central

Siemens, Helge; Jackstadt, Rene; Kaller, Markus; Hermeking, Heiko

2013-01-01

The c-Kit receptor tyrosine kinase is commonly over-expressed in different types of cancer. p53 activation is known to result in the down-regulation of c-Kit. However, the underlying mechanism has remained unknown. Here, we show that the p53-induced miR-34 microRNA family mediates repression of c-Kit by p53 via a conserved seed-matching sequence in the c-Kit 3'-UTR. Ectopic miR-34a resulted in a decrease in Erk signaling and transformation, which was dependent on the down-regulation of c-Kit expression. Furthermore, ectopic expression of c-Kit conferred resistance of colorectal cancer (CRC) cells to treatment with 5-fluorouracil (5-FU), whereas ectopic miR-34a sensitized the cells to 5-FU. After stimulation with c-Kit ligand/stem cell factor (SCF) Colo320 CRC cells displayed increased migration/invasion, whereas ectopic miR-34a inhibited SCF-induced migration/invasion. Activation of a conditional c-Kit allele induced several stemness markers in DLD-1 CRC cells. In primary CRC samples elevated c-Kit expression also showed a positive correlation with markers of stemness, such as Lgr5, CD44, OLFM4, BMI-1 and β-catenin. On the contrary, activation of a conditional miR-34a allele in DLD-1 cells diminished the expression of c-Kit and several stemness markers (CD44, Lgr5 and BMI-1) and suppressed sphere formation. MiR-34a also suppressed enhanced sphere-formation after exposure to SCF. Taken together, our data establish c-Kit as a new direct target of miR-34 and demonstrate that this regulation interferes with several c-Kit-mediated effects on cancer cells. Therefore, this regulation may be potentially relevant for future diagnostic and therapeutic approaches. PMID:24009080

Perineurial Glial Plasticity and the Role of TGF-β in the Development of the Blood-Nerve Barrier.

PubMed

Morris, Angela D; Lewis, Gwendolyn M; Kucenas, Sarah

2017-05-03

Precisely orchestrated interactions between spinal motor axons and their ensheathing glia are vital for forming and maintaining functional spinal motor nerves. Following perturbations to peripheral myelinating glial cells, centrally derived oligodendrocyte progenitor cells (OPCs) ectopically exit the spinal cord and myelinate peripheral nerves in myelin with CNS characteristics. However, whether remaining peripheral ensheathing glia, such as perineurial glia, properly encase the motor nerve despite this change in glial cell and myelin composition, remains unknown. Using zebrafish mutants in which OPCs migrate out of the spinal cord and myelinate peripheral motor axons, we assayed perineurial glial development, maturation, and response to injury. Surprisingly, in the presence of OPCs, perineurial glia exited the CNS normally. However, aspects of their development, response to injury, and function were altered compared with wildtype larvae. In an effort to better understand the plasticity of perineurial glia in response to myelin perturbations, we identified transforming growth factor-β1 as a partial mediator of perineurial glial development. Together, these results demonstrate the incredible plasticity of perineurial glia in the presence of myelin perturbations. SIGNIFICANCE STATEMENT Peripheral neuropathies can result from damage or dysregulation of the insulating myelin sheath surrounding spinal motor axons, causing pain, inefficient nerve conduction, and the ectopic migration of oligodendrocyte progenitor cells (OPCs), the resident myelinating glial cell of the CNS, into the periphery. How perineurial glia, the ensheathing cells that form the protective blood-nerve barrier, are impacted by this myelin composition change is unknown. Here, we report that certain aspects of perineurial glial development and injury responses are mostly unaffected in the presence of ectopic OPCs. However, perineurial glial function is disrupted along nerves containing centrally derived myelin, demonstrating that, although perineurial glial cells display plasticity despite myelin perturbations, the blood-nerve barrier is compromised in the presence of ectopic OPCs. Copyright © 2017 the authors 0270-6474/17/374790-18$15.00/0.

Tissue-Specific Gain of RTK Signalling Uncovers Selective Cell Vulnerability during Embryogenesis

PubMed Central

Audebert, Stéphane; Helmbacher, Françoise; Dono, Rosanna; Maina, Flavio

2015-01-01

The successive events that cells experience throughout development shape their intrinsic capacity to respond and integrate RTK inputs. Cellular responses to RTKs rely on different mechanisms of regulation that establish proper levels of RTK activation, define duration of RTK action, and exert quantitative/qualitative signalling outcomes. The extent to which cells are competent to deal with fluctuations in RTK signalling is incompletely understood. Here, we employ a genetic system to enhance RTK signalling in a tissue-specific manner. The chosen RTK is the hepatocyte growth factor (HGF) receptor Met, an appropriate model due to its pleiotropic requirement in distinct developmental events. Ubiquitously enhanced Met in Cre/loxP-based Rosa26 stopMet knock-in context (Del-R26 Met) reveals that most tissues are capable of buffering enhanced Met-RTK signalling thus avoiding perturbation of developmental programs. Nevertheless, this ubiquitous increase of Met does compromise selected programs such as myoblast migration. Using cell-type specific Cre drivers, we genetically showed that altered myoblast migration results from ectopic Met expression in limb mesenchyme rather than in migrating myoblasts themselves. qRT-PCR analyses show that ectopic Met in limbs causes molecular changes such as downregulation in the expression levels of Notum and Syndecan4, two known regulators of morphogen gradients. Molecular and functional studies revealed that ectopic Met expression in limb mesenchyme does not alter HGF expression patterns and levels, but impairs HGF bioavailability. Together, our findings show that myoblasts, in which Met is endogenously expressed, are capable of buffering increased RTK levels, and identify mesenchymal cells as a cell type vulnerable to ectopic Met-RTK signalling. These results illustrate that embryonic cells are sensitive to alterations in the spatial distribution of RTK action, yet resilient to fluctuations in signalling levels of an RTK when occurring in its endogenous domain of activity. PMID:26393505

Class I KNOX genes are associated with organogenesis during bulbil formation in Agave tequilana.

PubMed

Abraham-Juárez, María Jazmín; Martínez-Hernández, Aída; Leyva-González, Marco Antonio; Herrera-Estrella, Luis; Simpson, June

2010-09-01

Bulbil formation in Agave tequilana was analysed with the objective of understanding this phenomenon at the molecular and cellular levels. Bulbils formed 14-45 d after induction and were associated with rearrangements in tissue structure and accelerated cell multiplication. Changes at the cellular level during bulbil development were documented by histological analysis. In addition, several cDNA libraries produced from different stages of bulbil development were generated and partially sequenced. Sequence analysis led to the identification of candidate genes potentially involved in the initiation and development of bulbils in Agave, including two putative class I KNOX genes. Real-time reverse transcription-PCR and in situ hybridization revealed that expression of the putative Agave KNOXI genes occurs at bulbil initiation and specifically in tissue where meristems will develop. Functional analysis of Agave KNOXI genes in Arabidopsis thaliana showed the characteristic lobed phenotype of KNOXI ectopic expression in leaves, although a slightly different phenotype was observed for each of the two Agave genes. An Arabidopsis KNOXI (knat1) mutant line (CS30) was successfully complemented with one of the Agave KNOX genes and partially complemented by the other. Analysis of the expression of the endogenous Arabidopsis genes KNAT1, KNAT6, and AS1 in the transformed lines ectopically expressing or complemented by the Agave KNOX genes again showed different regulatory patterns for each Agave gene. These results show that Agave KNOX genes are functionally similar to class I KNOX genes and suggest that spatial and temporal control of their expression is essential during bulbil formation in A. tequilana.

Ectopical expression of FABP4 gene can induce bovine muscle-derived stem cells adipogenesis.

PubMed

Zhang, Le; Zhao, Yanfang; Ning, Yue; Wang, Hongbao; Zan, Linsen

2017-01-08

Fatty acid binding protein 4 (FABP4) plays a key role in Fatty acid catabolism in mammals. Findings from our previous studies have indicated that FABP4 neither affect the differentiation of bovine preadipocytes nor does it change the expression of upstream genes. To investigate whether ectopically expressed FABP4 can induces Muscle-Derived Stem Cells (MDSCs) lipid synthesis and understand the regulatory mechanism behind it. In this study, adenoviruses infection is achieved to ectopically expressed FABP4 in bovine MDSCs, RNA-seq analyses at the very early stages of induction were performed to reveal gene expression level changes during MDSCs transdifferentiation. Results showed FABP4 can induce bovine Muscle-Derived Stem Cells transdifferentiation into adipocyte-like cells, 23 genes' expression levels changed after 24 h inducing although there is no significant change in cell phenotypes. Along with induction time, more differently expressed genes (256 genes changes after 48 h induction) were screened out. These genes should be at the downstream of signal pathways and be regulated by the 23 genes identified before. Our findings may provide a unique new model for studying the molecular control of cattle cross-talk between adipose and skeletal muscle. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Ectopic Expression of BnaC.CP20.1 Results in Premature Tapetal Programmed Cell Death in Arabidopsis.

PubMed

Song, Liping; Zhou, Zhengfu; Tang, Shan; Zhang, Zhiqiang; Xia, Shengqian; Qin, Maomao; Li, Bao; Wen, Jing; Yi, Bin; Shen, Jinxiong; Ma, Chaozhi; Fu, Tingdong; Tu, Jinxing

2016-09-01

Tapetal programmed cell death (PCD) is essential in pollen grain development, and cysteine proteases are ubiquitous enzymes participating in plant PCD. Although the major papain-like cysteine proteases (PLCPs) have been investigated, the exact functions of many PLCPs are still poorly understood in PCD. Here, we identified a PLCP gene, BnaC.CP20.1, which was closely related to XP_013596648.1 from Brassica oleracea. Quantitative real-time PCR analysis revealed that BnaC.CP20.1 expression was down-regulated in male-sterile lines in oilseed rape, suggesting a connection between this gene and male sterility. BnaC.CP20.1 is especially active in the tapetum and microspores in Brassica napus from the uninucleate stage until formation of mature pollen grains during anther development. On expression of BnaC.CP20.1 prior to the tetrad stage, BnA9::BnaC.CP20.1 transgenic lines in Arabidopsis thaliana showed a male-sterile phenotype with shortened siliques containing fewer or no seeds by self-crossing. Scanning electron microscopy indicated that the reticulate exine was defective in aborted microspores. Callose degradation was delayed and microspores were not released from the tetrad in a timely fashion. Additionally, the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay indicated that BnaC.CP20.1 ectopic expression led to premature tapetal PCD. Transmission electron microscopy analyses further demonstrated that the pollen abortion was due to the absence of tectum connections to the bacula in the transgenic anthers. These findings suggest that timely expression of BnaC.CP20.1 is necessary for tapetal degeneration and pollen wall formation. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Ectopic expression of Msx-2 in posterior limb bud mesoderm impairs limb morphogenesis while inducing BMP-4 expression, inhibiting cell proliferation, and promoting apoptosis.

PubMed

Ferrari, D; Lichtler, A C; Pan, Z Z; Dealy, C N; Upholt, W B; Kosher, R A

1998-05-01

During early stages of chick limb development, the homeobox-containing gene Msx-2 is expressed in the mesoderm at the anterior margin of the limb bud and in a discrete group of mesodermal cells at the midproximal posterior margin. These domains of Msx-2 expression roughly demarcate the anterior and posterior boundaries of the progress zone, the highly proliferating posterior mesodermal cells underneath the apical ectodermal ridge (AER) that give rise to the skeletal elements of the limb and associated structures. Later in development as the AER loses its activity, Msx-2 expression expands into the distal mesoderm and subsequently into the interdigital mesenchyme which demarcates the developing digits. The domains of Msx-2 expression exhibit considerably less proliferation than the cells of the progress zone and also encompass several regions of programmed cell death including the anterior and posterior necrotic zones and interdigital mesenchyme. We have thus suggested that Msx-2 may be in a regulatory network that delimits the progress zone by suppressing the morphogenesis of the regions of the limb mesoderm in which it is highly expressed. In the present study we show that ectopic expression of Msx-2 via a retroviral expression vector in the posterior mesoderm of the progress zone from the time of initial formation of the limb bud severely impairs limb morphogenesis. Msx-2-infected limbs are typically very narrow along the anteroposterior axis, are occasionally truncated, and exhibit alterations in the pattern of formation of skeletal elements, indicating that as a consequence of ectopic Msx-2 expression the morphogenesis of large portions of the posterior mesoderm has been suppressed. We further show that Msx-2 impairs limb morphogenesis by reducing cell proliferation and promoting apoptosis in the regions of the posterior mesoderm in which it is ectopically expressed. The domains of ectopic Msx-2 expression in the posterior mesoderm also exhibit ectopic expression of BMP-4, a secreted signaling molecule that is coexpressed with Msx-2 during normal limb development in the anterior limb mesoderm, the posterior necrotic zone, and interdigital mesenchyme. This indicates that Msx-2 regulates BMP-4 expression and that the suppressive effects of Msx-2 on limb morphogenesis might be mediated in part by BMP-4. These studies indicate that during normal limb development Msx-2 is a key component of a regulatory network that delimits the boundaries of the progress zone by suppressing the morphogenesis of the regions of the limb mesoderm in which it is highly expressed, thus restricting the outgrowth and formation of skeletal elements and associated structures to the progress zone. We also report that rather large numbers of apoptotic cells as well as proliferating cells are present throughout the AER during all stages of normal limb development we have examined, indicating that many of the cells of the AER are continuously undergoing programmed cell death at the same time that new AER cells are being generated by cell proliferation. Thus, a balance between cell proliferation and programmed cell death may play a very important role in maintaining the activity of the AER. Copyright 1998 Academic Press.

Apoptosis-Inducing-Factor-Dependent Mitochondrial Function Is Required for T Cell but Not B Cell Function.

PubMed

Milasta, Sandra; Dillon, Christopher P; Sturm, Oliver E; Verbist, Katherine C; Brewer, Taylor L; Quarato, Giovanni; Brown, Scott A; Frase, Sharon; Janke, Laura J; Perry, S Scott; Thomas, Paul G; Green, Douglas R

2016-01-19

The role of apoptosis inducing factor (AIF) in promoting cell death versus survival remains controversial. We report that the loss of AIF in fibroblasts led to mitochondrial electron transport chain defects and loss of proliferation that could be restored by ectopic expression of the yeast NADH dehydrogenase Ndi1. Aif-deficiency in T cells led to decreased peripheral T cell numbers and defective homeostatic proliferation, but thymic T cell development was unaffected. In contrast, Aif-deficient B cells developed and functioned normally. The difference in the dependency of T cells versus B cells on AIF for function and survival correlated with their metabolic requirements. Ectopic Ndi1 expression rescued homeostatic proliferation of Aif-deficient T cells. Despite its reported roles in cell death, fibroblasts, thymocytes and B cells lacking AIF underwent normal death. These studies suggest that the primary role of AIF relates to complex I function, with differential effects on T and B cells. Copyright © 2016 Elsevier Inc. All rights reserved.

PreImplantation Factor in endometriosis: A potential role in inducing immune privilege for ectopic endometrium

PubMed Central

Scarpellini, Fabio; Marconi, Daniela; Rossi, Gabriele; Simmilion, Cedric; Mueller, Michael D.; Barnea, Eytan R.

2017-01-01

Endometriosis is a chronic inflammatory condition characterised by the growth of endometrial epithelial and stromal cells outside the uterine cavity. In addition to Sampson’s theory of retrograde menstruation, endometriosis pathogenesis is facilitated by a privileged inflammatory microenvironment, with T regulatory FoxP3+ expressing T cells (Tregs) being a significant factor. PreImplantation Factor (PIF) is a peptide essential for pregnancy recognition and development. An immune modulatory function of the synthetic PIF analog (sPIF) has been successfully confirmed in multiple animal models. We report that PIF is expressed in the epithelial ectopic cells in close proximity to FoxP3+ stromal cells. We provide evidence that PIF interacts with FoxP3+ cells and modulates cell viability, dependent on cell source and presence of inflammatory mediators. Our finding represent a novel PIF-based mechanism in endometriosis that has potential for novel therapeutics. PMID:28902871

Positive and Negative Regulation of Muscle Cell Identity by Members of the hedgehog and TGF-β Gene Families

PubMed Central

Du, Shao Jun; Devoto, Stephen H.; Westerfield, Monte; Moon, Randall T.

1997-01-01

We have examined whether the development of embryonic muscle fiber type is regulated by competing influences between Hedgehog and TGF-β signals, as previously shown for development of neuronal cell identity in the neural tube. We found that ectopic expression of Hedgehogs or inhibition of protein kinase A in zebrafish embryos induces slow muscle precursors throughout the somite but muscle pioneer cells only in the middle of the somite. Ectopic expression in the notochord of Dorsalin-1, a member of the TGF-β superfamily, inhibits the formation of muscle pioneer cells, demonstrating that TGF-β signals can antagonize the induction of muscle pioneer cells by Hedgehog. We propose that a Hedgehog signal first induces the formation of slow muscle precursor cells, and subsequent Hedgehog and TGF-β signals exert competing positive and negative influences on the development of muscle pioneer cells. PMID:9314535

Analysis of Nuclear Lamina Proteins in Myoblast Differentiation by Functional Complementation.

PubMed

Tapia, Olga; Gerace, Larry

2016-01-01

We describe straightforward methodology for structure-function mapping of nuclear lamina proteins in myoblast differentiation, using populations of C2C12 myoblasts in which the endogenous lamina components are replaced with ectopically expressed mutant versions of the proteins. The procedure involves bulk isolation of C2C12 cell populations expressing the ectopic proteins by lentiviral transduction, followed by depletion of the endogenous proteins using siRNA, and incubation of cells under myoblast differentiation conditions. Similar methodology may be applied to mouse embryo fibroblasts or to other cell types as well, for the identification and characterization of sequences of lamina proteins involved in functions that can be measured biochemically or cytologically.

Nuclear factor one B (NFIB) encodes a subtype-specific tumour suppressor in glioblastoma

PubMed Central

Stringer, Brett W.; Bunt, Jens; Day, Bryan W.; Barry, Guy; Jamieson, Paul R.; Ensbey, Kathleen S.; Bruce, Zara C.; Goasdoué, Kate; Vidal, Hélène; Charmsaz, Sara; Smith, Fiona M.; Cooper, Leanne T.; Piper, Michael

2016-01-01

Glioblastoma (GBM) is an essentially incurable and rapidly fatal cancer, with few markers predicting a favourable prognosis. Here we report that the transcription factor NFIB is associated with significantly improved survival in GBM. NFIB expression correlates inversely with astrocytoma grade and is lowest in mesenchymal GBM. Ectopic expression of NFIB in low-passage, patient-derived classical and mesenchymal subtype GBM cells inhibits tumourigenesis. Ectopic NFIB expression activated phospho-STAT3 signalling only in classical and mesenchymal GBM cells, suggesting a mechanism through which NFIB may exert its context-dependent tumour suppressor activity. Finally, NFIB expression can be induced in GBM cells by drug treatment with beneficial effects. PMID:27083054

The Flexibility of Ectopic Lipids

PubMed Central

Loher, Hannah; Kreis, Roland; Boesch, Chris; Christ, Emanuel

2016-01-01

In addition to the subcutaneous and the visceral fat tissue, lipids can also be stored in non-adipose tissue such as in hepatocytes (intrahepatocellular lipids; IHCL), skeletal (intramyocellular lipids; IMCL) or cardiac muscle cells (intracardiomyocellular lipids; ICCL). Ectopic lipids are flexible fuel stores that can be depleted by physical exercise and repleted by diet. They are related to obesity and insulin resistance. Quantification of IMCL was initially performed invasively, using muscle biopsies with biochemical and/or histological analysis. 1H-magnetic resonance spectroscopy (1H-MRS) is now a validated method that allows for not only quantifying IMCL non-invasively and repeatedly, but also assessing IHCL and ICCL. This review summarizes the current available knowledge on the flexibility of ectopic lipids. The available evidence suggests a complex interplay between quantitative and qualitative diet, fat availability (fat mass), insulin action, and physical exercise, all important factors that influence the flexibility of ectopic lipids. Furthermore, the time frame of the intervention on these parameters (short-term vs. long-term) appears to be critical. Consequently, standardization of physical activity and diet are critical when assessing ectopic lipids in predefined clinical situations. PMID:27649157

The Flexibility of Ectopic Lipids.

PubMed

Loher, Hannah; Kreis, Roland; Boesch, Chris; Christ, Emanuel

2016-09-14

In addition to the subcutaneous and the visceral fat tissue, lipids can also be stored in non-adipose tissue such as in hepatocytes (intrahepatocellular lipids; IHCL), skeletal (intramyocellular lipids; IMCL) or cardiac muscle cells (intracardiomyocellular lipids; ICCL). Ectopic lipids are flexible fuel stores that can be depleted by physical exercise and repleted by diet. They are related to obesity and insulin resistance. Quantification of IMCL was initially performed invasively, using muscle biopsies with biochemical and/or histological analysis. ¹H-magnetic resonance spectroscopy (¹H-MRS) is now a validated method that allows for not only quantifying IMCL non-invasively and repeatedly, but also assessing IHCL and ICCL. This review summarizes the current available knowledge on the flexibility of ectopic lipids. The available evidence suggests a complex interplay between quantitative and qualitative diet, fat availability (fat mass), insulin action, and physical exercise, all important factors that influence the flexibility of ectopic lipids. Furthermore, the time frame of the intervention on these parameters (short-term vs. long-term) appears to be critical. Consequently, standardization of physical activity and diet are critical when assessing ectopic lipids in predefined clinical situations.

Submandibular Lateral Ectopic Thyroid Tissue: Ultrasonography, Computed Tomography, and Scintigraphic Findings

PubMed Central

Çeliker, Metin; Beyazal Çeliker, Fatma; Turan, Arzu; Beyazal, Mehmet; Beyazal Polat, Hatice

2015-01-01

Ectopic thyroid can be encountered anywhere between the base of tongue and pretracheal region. The most common form is euthyroid neck mass. Herein, we aimed to present the findings of a female case with ectopic thyroid tissue localized in the left submandibular region. A 44-year-old female patient, who underwent bilateral subtotal thyroidectomy four years ago with the diagnosis of multinodular goiter, was admitted to our hospital due to a mass localized in the left submandibular area that gradually increased in the last six months. Neck ultrasonography, contrast-enhanced computed tomography, and scintigraphic examination were performed on the patient. On thyroid scintigraphy with Tc-99m pertechnetate, thyroid tissue activity uptake showing massive radioactivity was observed in the normal localization of the thyroid gland and in the submandibular localization. The focus in the submandibular region was excised. Pathological examination of the specimen showed normal thyroid follicle cells with no signs of malignancy. The submandibular mass is a rarely encountered lateral ectopic thyroid tissue. Accordingly, ectopic thyroid tissue should also be considered in the differential diagnosis of masses in the submandibular region. PMID:26634164

ATXN1L, CIC, and ETS Transcription Factors Modulate Sensitivity to MAPK Pathway Inhibition

PubMed Central

Wang, Belinda; Krall, Elsa Beyer; Aguirre, Andrew James; Kim, Miju; Widlund, Hans Ragnar; Doshi, Mihir Bhavik; Sicinska, Ewa; Sulahian, Rita; Goodale, Amy; Cowley, Glenn Spencer; Piccioni, Federica; Doench, John Gerard; Root, David Edward; Hahn, William Chun

2017-01-01

SUMMARY Intrinsic resistance and RTK-RAS-MAPK pathway reactivation has limited the effectiveness of MEK and RAF inhibitors (MAPKi) in RAS- and RAF-mutant cancers. To identify genes that modulate sensitivity to MAPKi, we performed genome scale CRISPR-Cas9 loss-of-function screens in two KRAS-mutant pancreatic cancer cell lines treated with the MEK1/2 inhibitor trametinib. Loss of CIC, a transcriptional repressor of ETV1, 4, and 5, promoted survival in the setting of MAPKi in cancer cells derived from several lineages. ATXN1L deletion, which reduces CIC protein, or ectopic expression of ETV1, 4, or 5 also modulated sensitivity to trametinib. ATXN1L expression inversely correlates with response to MAPKi inhibition in clinical studies. These observations identify the ATXN1L-CIC-ETS transcription factor axis as a mediator of resistance to MAPKi. PMID:28178529

Misexpression of cyclin B3 leads to aberrant spermatogenesis.

PubMed

Refik-Rogers, Jale; Manova, Katia; Koff, Andrew

2006-09-01

Mus musculus cyclin B3 is an early meiotic cyclin that is expressed in leptotene and zygotene phases during gametogenesis. In order to determine whether downregulation of cyclin B3 at zygotene-pachytene transition was important for normal spermatogenesis, we investigated the consequences of expressing H. sapiens cyclin B3 after zygotene in mouse testes. Prolonging expression of cyclin B3 until the end of meiosis led to a reduction in sperm counts and disruption of spermatogenesis in four independent lines of transgenic mice. There were three distinct morphological defects associated with the ectopic expression of cyclin B3. Seminiferous tubules were either depleted of germ cells, had an abnormal cell mass in the lumen, or were characterized by the presence of abnormal round spermatids. These defects were associated with increased apoptosis in the testes. These results suggest that downregulation of cyclin B3 at the zygotene-pachytene transition is required to ensure normal spermatogenesis.

Expression of a repressor form of the Arabidopsis thaliana transcription factor TCP16 induces the formation of ectopic meristems.

PubMed

Uberti-Manassero, Nora G; Coscueta, Ezequiel R; Gonzalez, Daniel H

2016-11-01

Plants that express a fusion of the Arabidopsis thaliana class I TCP transcription factor TCP16 to the EAR repressor domain develop several phenotypic alterations, including rounder leaves, short petioles and pedicels, and delayed elongation of sepals, petals and anthers. In addition, these plants develop lobed cotyledons and ectopic meristems. Ectopic meristems are formed on the adaxial side of cotyledon petioles and arise from a cleft that is formed at this site. Analysis of the expression of reporter genes indicated that meristem genes are reactivated at the site of emergence of ectopic meristems, located near the bifurcation of cotyledon veins. The plants also show increased transcript levels of the boundary-specific CUP-SHAPED COTYLEDON (CUC) genes. The results suggest that TCP16 is able to modulate the induction of meristematic programs and the differentiation state of plant cells. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

High Titers ofChlamydia trachomatis Antibodies in Brazilian Women with Tubal Occlusion or Previous Ectopic Pregnancy

PubMed Central

Machado, A. C. S.; Guimarães, E. M. B.; Sakurai, E.; Fioravante, F. C. R.; Amaral, W. N.; Alves, M. F. C.

2007-01-01

Objective. To evaluate serum chlamydia antibody titers (CATs) in tubal occlusion or previous ectopic pregnancy and the associated risk factors.Methods. The study population consisted of 55 women wih tubal damage and 55 parous women. CAT was measured using the whole-cell inclusion immunofluorescence test and cervical chlamydial DNA detected by PCR. Odds ratios were calculated to assess variables associated withC. trachomatis infection.Results. The prevalence of chlamydial antibodies and antibody titers in women with tubal occlusion or previous ectopic pregnancy was significantly higher (P < .01) than in parous women. Stepwise logistic regression analysis showed that chlamydia IgG antibodies were associated with tubal damage and with a larger number of lifetime sexual partners.Conclusions. Chlamydia antibody titers were associated with tubal occlusion, prior ectopic pregnancy, and with sexual behavior, suggesting that a chlamydia infection was the major contributor to the tubal damage in these women. PMID:17541464

Activation of the mouse Oct4 promoter in medaka embryonic stem cells and its use for ablation of spontaneous differentiation.

PubMed

Hong, Yunhan; Winkler, Christoph; Liu, Tongming; Chai, Guixuan; Schartl, Manfred

2004-07-01

The determination and maintenance of the cell fate is ultimately due to differential gene activity. In the mouse, expression of the transcription factor Oct4 is high in totipotent inner cell mass, germ cells and undifferentiated embryonic stem (ES) cells, but dramatically reduced or extinct upon differentiation. Here, we show that medaka blastula embryos and cells of the ES cell line MES1 are able to activate the Oct4 promoter. Ectopic expression of a fusion gene for beta-galactosidase and neomycin resistance from the Oct4 promoter conferred resistance to G418. G418 selection led to a homogeneous population of undifferentiated ES cells which were able to undergo induced or directed differentiation into various cell types including neuron-like cells and melanocytes. Furthermore, GFP-labeled GOF18geo-MES1 cells after differentiation ablation were able to contribute to a wide variety of organ systems derived from all the three germ layers. Most importantly, we show that drug ablation of differentiation on the basis of Oct4 promoter is a useful tool to improve ES cell cultivation and chimera formation: MES1 cells after differentiation ablation appeared to be better donors than the parental MES1 line, as the permissive number of input donor cells increases from 100 to 200, resulting in an enhanced degree of chimerism. Taken together, some transcription factors and cis-acting regulatory sequences controlling totipotency-specific gene expression appear to be conserved between mammals and fish, and medaka ES cells offer an in vitro system for characterizing the expression of totipotency-specific genes such as putative Oct4 homologs from fish.

Complete adult neurogenesis within a Wallerian degenerating nerve expressed as an ectopic ganglion.

PubMed

Nakano, Tomonori; Kurimoto, Shigeru; Kato, Shuichi; Asano, Kenichi; Hirata, Takuma; Kiyama, Hiroshi; Hirata, Hitoshi

2018-06-01

Neurogenesis in the adult peripheral nervous system remains to be demonstrated. We transplanted embryonic neural stem cells into a Wallerian degenerating nerve graft and observed development of a nodular structure consisting of neurons, glia, and Schwann cells. Histological analysis revealed a structure loosely resembling the spinal cord, including a synaptic network that formed along the neuron. Furthermore, the new axons reinnervated the paralysed muscle, forming both de novo and revived neuromuscular junctions. Reinnervation of the paralysed muscle resulted in significantly greater mean wet muscle weight and muscle fibre cross-sectional area on the cell transplantation side than on the surgical control side (body weight 0.071 ± 0.011% vs. 0.051 ± 0.007%, p = .006; area 355.6 ± 345.2 vs. 114.0 ± 132.0 μm 2 , p < .001). Electrophysiological experiments demonstrated a functional connection between the neurons and muscle; hence, we identified this nodule as an ectopic ganglion. Surprisingly, in green rat experiments, most of these glial cells, but none of the neurons, expressed enhanced green fluorescent protein, suggesting that the cells constituting the ectopic ganglion were derived from both transplanted stem cells and endogenous stem cells. Such adult neurogenesis in a peripheral nerve related to neural stem cell transplantation has not been reported previously, and these results form the basis for a novel regenerative medicine approach in paralysed muscle. Copyright © 2018 John Wiley & Sons, Ltd.

MicroRNA-365 inhibits growth, invasion and metastasis of malignant melanoma by targeting NRP1 expression.

PubMed

Bai, Juanjuan; Zhang, Zhongling; Li, Xing; Liu, Huifan

2015-01-01

The role of miR-365 in cancer cells seemed controversial in previous studies. We thereby in this article aimed to define the role of miR-365 in malignant melanoma (MM) pathogenesis. We detected miR-365 expression in malignant melanoma cell lines and then investigated the effects of miR-365 on the metastasis and malignancy of melanoma cells. The correlation between miR-365 level and NRP1 (neuropilin1) was further investigated in clinical malignant melanoma specimens. MiR-365 was strongly down-regulated in malignant melanoma (MM) tissues and cell lines, and its expression levels were associated with lymph node metastasis and clinical stage, as well as overall survival and replase-free survival of MM. We also found that ectopic expression of miR-365 inhibited MM cell proliferation and MM metastasis in vitro and in vivo. We further identified a novel mechanism of miR-365 to suppress MM growth and metastasis. NRP1 was proved to be a direct target of miR-365, using luciferase assay and western blot. NRP1 over-expression in miR-365 expressing cells could rescue invasion and growth defects of miR-365. In addition, miR-365 expression inversely correlated with NRP1 protein levels in MM. Our data suggest that miR-365 functions as a tumor suppressor in MM development and progression, and holds promise as a prognostic biomarker and potential therapeutic target for MM.

Long noncoding RNA BDNF-AS is associated with clinical outcomes and has functional role in human prostate cancer.

PubMed

Li, Wensheng; Dou, Zhongling; We, Shuguang; Zhu, Zhiyi; Pan, Dong; Jia, Zhaohui; Liu, Hui; Wang, Xiaobin; Yu, Guoqiang

2018-06-01

The underlying molecular mechanisms of prostate cancer (CaP) are largely unknown. We investigated the expression, prognostic value and functional role of long non-coding RNA (lncRNA) brain-derived neurotrophin factor antisense (BDNF-AS) in CaP. Clinical tumor samples were excised from patients with CaP. Their endogenous BDNF-AS expression levels were evaluated by qRT-PCR. Correlations between CaP patients' endogenous BDNF-AS expression and their clinicopathological factors, overall survival were statistically analyzed. BDNF-AS expression levels were also probed in immortal CaP cell lines. In LNCaP and PC-3 cells, BDNF-AS was ectopically overexpressed through lentiviral transduction. The functions of BDNF-AS upregulation on CaP cell development were evaluated both in vitro and in vivo. BDNF-AS was downregulated in human CaP tumors. Low BDNF-AS expression was correlated with CaP patients' poor prognosis and shorter overall survival. BDNF-AS was also found to be lowly expressed in CaP cell lines. In LNCaP and PC-3 cells, lentivirus-driven BDNF-AS overexpression exerted significantly tumor-suppressing effects on hindering cancer cell proliferation and invasion in vitro, and explant growth in vivo. Downregulated BDNF-AS in CaP patients could be a potential prognostic biomarker for predicating poor prognosis and survival. Upregulating BDNF-AS may be a novel molecular intervening target for CaP treatment. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

The GDNF Target Vsnl1 Marks the Ureteric Tip

PubMed Central

Ola, Roxana; Jakobson, Madis; Kvist, Jouni; Perälä, Nina; Kuure, Satu; Braunewell, Karl-Heinz; Bridgewater, Darren; Rosenblum, Norman D.; Chilov, Dmitri; Immonen, Tiina; Sainio, Kirsi

2011-01-01

Glial cell line-derived neurotrophic factor (GDNF) is indispensable for ureteric budding and branching. If applied exogenously, GDNF promotes ectopic ureteric buds from the Wolffian duct. Although several downstream effectors of GDNF are known, the identification of early response genes is incomplete. Here, microarray screening detected several GDNF-regulated genes in the Wolffian duct, including Visinin like 1 (Vsnl1), which encodes a neuronal calcium-sensor protein. We observed renal Vsnl1 expression exclusively in the ureteric epithelium, but not in Gdnf-null kidneys. In the tissue culture of Gdnf-deficient kidney primordium, exogenous GDNF and alternative bud inducers (FGF7 and follistatin) restored Vsnl1 expression. Hence, Vsnl1 characterizes the tip of the ureteric bud epithelium regardless of the inducer. In the tips, Vsnl1 showed a mosaic expression pattern that was mutually exclusive with β-catenin transcriptional activation. Vsnl1 was downregulated in both β-catenin-stabilized and β-catenin-deficient kidneys. Moreover, in a mouse collecting duct cell line, Vsnl1 compromised β-catenin stability, suggesting a counteracting relationship between Vsnl1 and β-catenin. In summary, Vsnl1 marks ureteric bud tips in embryonic kidneys, and its mosaic pattern demonstrates a heterogeneity of cell types that may be critical for normal ureteric branching. PMID:21289216

Synaptotagmin 1 causes phosphatidyl inositol lipid-dependent actin remodeling in cultured non-neuronal and neuronal cells

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

Johnsson, Anna-Karin; Karlsson, Roger, E-mail: roger.karlsson@wgi.su.se

2012-01-15

Here we demonstrate that a dramatic actin polymerizing activity caused by ectopic expression of the synaptic vesicle protein synaptotagmin 1 that results in extensive filopodia formation is due to the presence of a lysine rich sequence motif immediately at the cytoplasmic side of the transmembrane domain of the protein. This polybasic sequence interacts with anionic phospholipids in vitro, and, consequently, the actin remodeling caused by this sequence is interfered with by expression of a phosphatidyl inositol (4,5)-bisphosphate (PIP2)-targeted phosphatase, suggesting that it intervenes with the function of PIP2-binding actin control proteins. The activity drastically alters the behavior of a rangemore » of cultured cells including the neuroblastoma cell line SH-SY5Y and primary cortical mouse neurons, and, since the sequence is conserved also in synaptotagmin 2, it may reflect an important fine-tuning role for these two proteins during synaptic vesicle fusion and neurotransmitter release.« less

Expression of the voltage-sensing phosphatase gene in the chick embryonic tissues and in the adult cerebellum.

PubMed

Yamaguchi, Shinji; Aoki, Naoya; Kitajima, Takaaki; Okamura, Yasushi; Homma, Koichi J

2014-10-01

Voltage-sensing phosphatase (VSP) consists of a transmembrane voltage sensor domain (VSD) and the cytoplasmic domain with phosphoinositide-phosphatase activities. It operates as the voltage sensor and directly translates membrane potential into phosphoinositide turnover by coupling VSD to the cytoplasmic domain. VSPs are evolutionarily conserved from marine invertebrate up to humans. Recently, we demonstrated that ectopic expression of the chick ortholog of VSP, Gg-VSP, in a fibroblast cell line caused characteristic cell process outgrowths. Co-expression of chick PTEN suppressed such morphological change, suggesting that VSP regulates cell shape by increasing PI(3,4)P2. However, the in vivo function of Gg-VSP remains unclear. Here, we showed that in chick embryos Gg-VSP is expressed in the stomach, mesonephros, pharyngeal arch, limb bud, somites, floor plate of neural tube, and notochord. In addition, both Gg-VSP transcripts and the protein were found in the cerebellar Purkinje neurons. These findings provide an insight into the physiological functions of VSP.

Aromatase expression increases the survival and malignancy of estrogen receptor positive breast cancer cells.

PubMed

Mukhopadhyay, Keya De; Liu, Zhao; Bandyopadhyay, Abhik; Kirma, Nameer B; Tekmal, Rajeshwar R; Wang, Shui; Sun, Lu-Zhe

2015-01-01

In postmenopausal women, local estrogen produced by adipose stromal cells in the breast is believed to support estrogen receptor alpha (ERα) positive breast cancer cell survival and growth. This raises the question of how the ERα positive metastatic breast cancer cells survive after they enter blood and lymph circulation, where estrogen level is very low in postmenopausal women. In this study, we show that the aromatase expression increased when ERα positive breast cancer cells were cultured in suspension. Furthermore, treatment with the aromatase substrate, testosterone, inhibited suspension culture-induced apoptosis whereas an aromatase inhibitor attenuated the effect of testosterone suggesting that suspended circulating ERα positive breast cancer cells may up-regulate intracrine estrogen activity for survival. Consistent with this notion, a moderate level of ectopic aromatase expression rendered a non-tumorigenic ERα positive breast cancer cell line not only tumorigenic but also metastatic in female nude mice without exogenous estrogen supplementation. The increased malignant phenotype was confirmed to be due to aromatase expression as the growth of orthotopic tumors regressed with systemic administration of an aromatase inhibitor. Thus, our study provides experimental evidence that aromatase plays an important role in the survival of metastatic ERα breast cancer cells by suppressing anoikis.

Polyphosphate is a key factor for cell survival after DNA damage in eukaryotic cells.

PubMed

Bru, Samuel; Samper-Martín, Bàrbara; Quandt, Eva; Hernández-Ortega, Sara; Martínez-Laínez, Joan M; Garí, Eloi; Rafel, Marta; Torres-Torronteras, Javier; Martí, Ramón; Ribeiro, Mariana P C; Jiménez, Javier; Clotet, Josep

2017-09-01

Cells require extra amounts of dNTPs to repair DNA after damage. Polyphosphate (polyP) is an evolutionary conserved linear polymer of up to several hundred inorganic phosphate (Pi) residues that is involved in many functions, including Pi storage. In the present article, we report on findings demonstrating that polyP functions as a source of Pi when required to sustain the dNTP increment essential for DNA repair after damage. We show that mutant yeast cells without polyP produce less dNTPs upon DNA damage and that their survival is compromised. In contrast, when polyP levels are ectopically increased, yeast cells become more resistant to DNA damage. More importantly, we show that when polyP is reduced in HEK293 mammalian cell line cells and in human dermal primary fibroblasts (HDFa), these cells become more sensitive to DNA damage, suggesting that the protective role of polyP against DNA damage is evolutionary conserved. In conclusion, we present polyP as a molecule involved in resistance to DNA damage and suggest that polyP may be a putative target for new approaches in cancer treatment or prevention. Copyright © 2017 Elsevier B.V. All rights reserved.

Ectopic lymphoid structures support ongoing production of class-switched autoantibodies in rheumatoid synovium.

PubMed

Humby, Frances; Bombardieri, Michele; Manzo, Antonio; Kelly, Stephen; Blades, Mark C; Kirkham, Bruce; Spencer, Jo; Pitzalis, Costantino

2009-01-13

Follicular structures resembling germinal centres (GCs) that are characterized by follicular dendritic cell (FDC) networks have long been recognized in chronically inflamed tissues in autoimmune diseases, including the synovium of rheumatoid arthritis (RA). However, it is debated whether these ectopic structures promote autoimmunity and chronic inflammation driving the production of pathogenic autoantibodies. Anti-citrullinated protein/peptide antibodies (ACPA) are highly specific markers of RA, predict a poor prognosis, and have been suggested to be pathogenic. Therefore, the main study objectives were to determine whether ectopic lymphoid structures in RA synovium: (i) express activation-induced cytidine deaminase (AID), the enzyme required for somatic hypermutation and class-switch recombination (CSR) of Ig genes; (ii) support ongoing CSR and ACPA production; and (iii) remain functional in a RA/severe combined immunodeficiency (SCID) chimera model devoid of new immune cell influx into the synovium. Using immunohistochemistry (IHC) and quantitative Taqman real-time PCR (QT-PCR) in synovial tissue from 55 patients with RA, we demonstrated that FDC+ structures invariably expressed AID with a distribution resembling secondary lymphoid organs. Further, AID+/CD21+ follicular structures were surrounded by ACPA+/CD138+ plasma cells, as demonstrated by immune reactivity to citrullinated fibrinogen. Moreover, we identified a novel subset of synovial AID+/CD20+ B cells outside GCs resembling interfollicular large B cells. In order to gain direct functional evidence that AID+ structures support CSR and in situ manufacturing of class-switched ACPA, 34 SCID mice were transplanted with RA synovium and humanely killed at 4 wk for harvesting of transplants and sera. Persistent expression of AID and Igamma-Cmu circular transcripts (identifying ongoing IgM-IgG class-switching) was observed in synovial grafts expressing FDCs/CD21L. Furthermore, synovial mRNA levels of AID were closely associated with circulating human IgG ACPA in mouse sera. Finally, the survival and proliferation of functional B cell niches was associated with persistent overexpression of genes regulating ectopic lymphoneogenesis. Our demonstration that FDC+ follicular units invariably express AID and are surrounded by ACPA-producing plasma cells provides strong evidence that ectopic lymphoid structures in the RA synovium are functional and support autoantibody production. This concept is further confirmed by evidence of sustained AID expression, B cell proliferation, ongoing CSR, and production of human IgG ACPA from GC+ synovial tissue transplanted into SCID mice, independently of new B cell influx from the systemic circulation. These data identify AID as a potential therapeutic target in RA and suggest that survival of functional synovial B cell niches may profoundly influence chronic inflammation, autoimmunity, and response to B cell-depleting therapies.

The Inactivation of Arx in Pancreatic α-Cells Triggers Their Neogenesis and Conversion into Functional β-Like Cells

PubMed Central

Courtney, Monica; Gjernes, Elisabet; Druelle, Noémie; Ravaud, Christophe; Vieira, Andhira; Ben-Othman, Nouha; Pfeifer, Anja; Avolio, Fabio; Leuckx, Gunter; Lacas-Gervais, Sandra; Burel-Vandenbos, Fanny; Ambrosetti, Damien; Hecksher-Sorensen, Jacob; Ravassard, Philippe; Heimberg, Harry; Mansouri, Ahmed; Collombat, Patrick

2013-01-01

Recently, it was demonstrated that pancreatic new-born glucagon-producing cells can regenerate and convert into insulin-producing β-like cells through the ectopic expression of a single gene, Pax4. Here, combining conditional loss-of-function and lineage tracing approaches, we show that the selective inhibition of the Arx gene in α-cells is sufficient to promote the conversion of adult α-cells into β-like cells at any age. Interestingly, this conversion induces the continuous mobilization of duct-lining precursor cells to adopt an endocrine cell fate, the glucagon+ cells thereby generated being subsequently converted into β-like cells upon Arx inhibition. Of interest, through the generation and analysis of Arx and Pax4 conditional double-mutants, we provide evidence that Pax4 is dispensable for these regeneration processes, indicating that Arx represents the main trigger of α-cell-mediated β-like cell neogenesis. Importantly, the loss of Arx in α-cells is sufficient to regenerate a functional β-cell mass and thereby reverse diabetes following toxin-induced β-cell depletion. Our data therefore suggest that strategies aiming at inhibiting the expression of Arx, or its molecular targets/co-factors, may pave new avenues for the treatment of diabetes. PMID:24204325

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

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

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

Elevated Cyclic AMP Levels in T Lymphocytes Transformed by Human T-Cell Lymphotropic Virus Type 1▿

PubMed Central

Kress, Andrea K.; Schneider, Grit; Pichler, Klemens; Kalmer, Martina; Fleckenstein, Bernhard; Grassmann, Ralph

2010-01-01

Human T-cell lymphotropic virus type 1 (HTLV-1), the cause of adult T-cell leukemia/lymphoma (ATLL), transforms CD4+ T cells to permanent growth through its transactivator Tax. HTLV-1-transformed cells share phenotypic properties with memory and regulatory T cells (T-reg). Murine T-reg-mediated suppression employs elevated cyclic AMP (cAMP) levels as a key regulator. This led us to determine cAMP levels in HTLV-1-transformed cells. We found elevated cAMP concentrations as a consistent feature of all HTLV-1-transformed cell lines, including in vitro-HTLV-1-transformed, Tax-transformed, and patient-derived cells. In transformed cells with conditional Tax expression, high cAMP levels coincided with the presence of Tax but were lost without it. However, transient ectopic expression of Tax alone was not sufficient to induce cAMP. We found specific downregulation of the cAMP-degrading phosphodiesterase 3B (PDE3B) in HTLV-1-transformed cells, which was independent of Tax in transient expression experiments. This is in line with the notion that PDE3B transcripts and cAMP levels are inversely correlated. Overexpression of PDE3B led to a decrease of cAMP in HTLV-1-transformed cells. Decreased expression of PDE3B was associated with inhibitory histone modifications at the PDE3B promoter and the PDE3B locus. In summary, Tax transformation and its continuous expression contribute to elevated cAMP levels, which may be regulated through PDE3B suppression. This shows that HTLV-1-transformed cells assume biological features of long-lived T-cell populations that potentially contribute to viral persistence. PMID:20573814

Ectopic expression of Msx2 in mammalian myotubes recapitulates aspects of amphibian muscle dedifferentiation.

PubMed

Yilmaz, Atilgan; Engeler, Rachel; Constantinescu, Simona; Kokkaliaris, Konstantinos D; Dimitrakopoulos, Christos; Schroeder, Timm; Beerenwinkel, Niko; Paro, Renato

2015-11-01

In contrast to urodele amphibians and teleost fish, mammals lack the regenerative responses to replace large body parts. Amphibian and fish regeneration uses dedifferentiation, i.e., reversal of differentiated state, as a means to produce progenitor cells to eventually replace damaged tissues. Therefore, induced activation of dedifferentiation responses in mammalian tissues holds an immense promise for regenerative medicine. Here we demonstrate that ectopic expression of Msx2 in cultured mouse myotubes recapitulates several aspects of amphibian muscle dedifferentiation. We found that MSX2, but not MSX1, leads to cellularization of myotubes and downregulates the expression of myotube markers, such as MHC, MRF4 and myogenin. RNA sequencing of myotubes ectopically expressing Msx2 showed downregulation of over 500 myotube-enriched transcripts and upregulation of over 300 myoblast-enriched transcripts. MSX2 selectively downregulated expression of Ptgs2 and Ptger4, two members of the prostaglandin pathway with important roles in myoblast fusion during muscle differentiation. Ectopic expression of Msx2, as well as Msx1, induced partial cell cycle re-entry of myotubes by upregulating CyclinD1 expression but failed to initiate S-phase. Finally, MSX2-induced dedifferentiation in mouse myotubes could be recapitulated by a pharmacological treatment with trichostatin A (TSA), bone morphogenetic protein 4 (BMP4) and fibroblast growth factor 1 (FGF1). Together, these observations indicate that MSX2 is a major driver of dedifferentiation in mammalian muscle cells. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Ectopic bone formation and chondrodysplasia in transgenic mice carrying the rat C3(1)/T{sub AG} fusion gene

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

Green, J.E.; Maroulakou, I.G.; Anver, M.

Transgenic mice expressing the SV40 large T-antigen (T{sup AG}) under the regultory control of the hormone-responsive rat C3(1) prostatein promoter develop unusual bone and cartilage lesions, as well as ectopic bone and cartilage formation. Two lines of transgenic animals have been propagated in which the expression of the transgene in chondrocytes results in a mild to moderate generalized disorganization of cartilage growth which appears to affect multiple tissues, including the trachea, ear pinna and articular cartilage. The epiphyseal plates are also affected with normal architecture of the zones of proliferation and maturation, but marked elongation of the zone of hypertrophy.more » Immunocytochemistry demonstrates that expression of T{sup AG} is limited to the zone of hypertropny in the epiphyseal plates, suggesting that the chondrocytes become hormone-responsive at this particular stage of differentiation. Normal mineralization and trabecular formation in long bone appears to occur. Ectopic bone and cartilage formation occurs in the foot pads of the fore- and hind- feet over the course of several months. This is preceded by proliferation of sweat gland epithelial cells followed by the appearance of nodules of cartilage and bone. The nodules are closely associated with proliferating epithelium but are not contiguous with bony structures normally found in the feet. The roles of BMP`s, growth factors, oncogenes and hormones in the development of these lesions will be presented. These transgenic animals may provide new insights into hormone-responsiveness of chondrocytes, as well as factors involved in the processes of bone and cartilage differentiation and growth. These transgenic animals may serve as a useful model for human heterotopic bone formation.« less

Regulation of miRNA-29c and its downstream pathways in preneoplastic progression of triple-negative breast cancer

PubMed Central

Bhardwaj, Anjana; Singh, Harpreet; Rajapakshe, Kimal; Tachibana, Kazunoshin; Ganesan, Nivetha; Pan, Yinghong; Gunaratne, Preethi H.; Coarfa, Cristian; Bedrosian, Isabelle

2017-01-01

Little is understood about the early molecular drivers of triple-negative breast cancer (TNBC), making the identification of women at risk and development of targeted therapy for prevention significant challenges. By sequencing a TNBC cell line-based breast cancer progression model we have found that miRNA-29c is progressively lost during TNBC tumorigenesis. In support of the tumor suppressive role of miRNA 29c, we found that low levels predict poor overall patient survival and, conversely, that ectopic expression of miRNA-29c in preneoplastic cell models inhibits growth. miRNA-29c exerts its growth inhibitory effects through direct binding and regulation of TGFB-induced factor homeobox 2 (TGIF2), CAMP-responsive element binding protein 5 (CREB5), and V-Akt murine thymoma viral oncogene homolog 3 (AKT3). miRNA-29c regulation of these gene targets seems to be functionally relevant, as TGIF2, CREB5, and AKT3 were able to rescue the inhibition of cell proliferation and colony formation caused by ectopic expression of miRNA-29c in preneoplastic cells. AKT3 is an oncogene of known relevance in breast cancer, and as a proof of principle we show that inhibition of phosphoinositide 3-kinase (PI3K) activity, a protein upstream of AKT3, suppressed proliferation in TNBC preneoplastic cells. We explored additional opportunities for prevention of TNBC by studying the regulation of miRNA-29c and identified DNA methylation to have a role in the inhibition of miRNA-29c during TNBC tumorigenesis. Consistent with these observations, we found 5 aza-cytadine to relieve the suppression of miRNA-29c. Together, these results demonstrate that miRNA-29c loss plays a key role in the early development of TNBC. PMID:28160548

The role of BST2/tetherin in infection with the feline retroviruses

PubMed Central

Dietrich, Isabelle; Hosie, Margaret J.; Willett, Brian J.

2014-01-01

The recently identified host restriction factor tetherin (BST-2, CD317) potently inhibits the release of nascent retrovirus particles from infected cells. Recently, we reported the identification and characterization of tetherin as a novel feline retroviral restriction factor. Based on homology to human tetherin we identified a putative tetherin gene in the genome of the domestic cat (Felis catus) which was found to be expressed in different feline cell lines both prior to and post treatment with either type I or type II interferon (IFN). The predicted structure of feline tetherin (feTHN) was that of a type II single-pass transmembrane protein encoding an N-terminal transmembrane anchor, central predicted coiled-coil bearing extracellular domain to promote dimerization, and a C-terminal GPI-anchor, consistent with conservation of structure between human and feline tetherin. FeTHN displayed potent inhibition of feline immunodeficiency virus (FIV) and human immunodeficiency virus type 1 (HIV-1) particle release in single-cycle replication assays. Notably, feTHN activity was resistant to antagonism by HIV-1 Vpu. However, stable ectopic expression of feTHN mRNA in different feline cell lines had no inhibitory effect on the growth of diverse primary or cell culture-adapted strains of FIV. Hence, whereas feline tetherin efficiently blocks viral particle release in single-cycle replication assays, it might not prevent dissemination of feline retroviruses in vivo. PMID:21715020

Brca1 regulates in vitro differentiation of mammary epithelial cells.

PubMed

Kubista, Marion; Rosner, Margit; Kubista, Ernst; Bernaschek, Gerhard; Hengstschläger, Markus

2002-07-18

Murine Brca1 is widely expressed during development in different tissues. Why alterations of BRCA1 lead specifically to breast and ovarian cancer is currently not clarified. Here we show that Brca1 protein expression is upregulated during mammary epithelial differentiation of HC11 cells, during differentiation of C2C12 myoblasts into myotubes and during neuronal differentiation of N1E-115 cells. Ectopic overexpression of BRCA1 and downregulation of endogenous Brca1 expression specifically affect the regulation of mammary epithelial cell differentiation. Accelerated mammary epithelial cell differentiation upon high ectopic BRCA1 expression is not a consequence of the anti-proliferative capacity of this tumor suppressor and independent of functional p53. Overexpression of the BRCA1 variant lacking the large central exon 11 has no effects on mammary epithelial cell differentiation. These data provide new insights into the cellular role of Brca1.

Cancerous inhibitor of protein phosphatase 2A determines bortezomib-induced apoptosis in leukemia cells

PubMed Central

Liu, Chun-Yu; Shiau, Chung-Wai; Kuo, Hsin-Yu; Huang, Hsiang-Po; Chen, Ming-Huang; Tzeng, Cheng-Hwai; Chen, Kuen-Feng

2013-01-01

The multiple cellular targets affected by proteasome inhibition implicate a potential role for bortezomib, a first-in-class proteasome inhibitor, in enhancing antitumor activities in hematologic malignancies. Here, we examined the antitumor activity and drug targets of bortezomib in leukemia cells. Human leukemia cell lines were used for in vitro studies. Drug efficacy was evaluated by apoptosis assays and associated molecular events assessed by Western Blot. Gene silencing was performed by small interference RNA. Drug was tested in vivo in xenograft models of human leukemia cell lines and in primary leukemia cells. Clinical samples were assessed by immunohistochemical staining. Bortezomib differentially induced apoptosis in leukemia cells that was independent of its proteasome inhibition. Cancerous inhibitor of protein phosphatase 2A, a cellular inhibitor of protein phosphatase 2A, mediated the apoptotic effect of bortezomib. Bortezomib increased protein phosphatase 2A activity in sensitive leukemia cells (HL-60 and KG-1), but not in resistant cells (MOLT-3 and K562). Bortezomib’s downregulation of cancerous inhibitor of protein phosphatase 2A and phospho-Akt correlated with its drug sensitivity. Furthermore, cancerous inhibitor of protein phosphatase 2A negatively regulated protein phosphatase 2A activity. Ectopic expression of CIP2A up-regulated phospho-Akt and protected HL-60 cells from bortezomib-induced apoptosis, whereas silencing CIP2A overcame the resistance to bortezomib-induced apoptosis in MOLT3 and K562 cells. Importantly, bortezomib exerted in vivo antitumor activity in HL-60 xenografted tumors and induced cell death in some primary leukemic cells. Cancerous inhibitor of protein phosphatase 2A was expressed in leukemic blasts from bone marrow samples. Cancerous inhibitor of protein phosphatase 2A plays a major role in mediating bortezomib-induced apoptosis in leukemia cells. PMID:22983581

Progression of neuronal and synaptic remodeling in the rd10 mouse model of retinitis pigmentosa.

PubMed

Phillips, M Joseph; Otteson, Deborah C; Sherry, David M

2010-06-01

The Pde6b(rd10) (rd10) mouse has a moderate rate of photoreceptor degeneration and serves as a valuable model for human autosomal recessive retinitis pigmentosa (RP). We evaluated the progression of neuronal remodeling of second- and third-order retinal cells and their synaptic terminals in retinas from Pde6b(rd10) (rd10) mice at varying stages of degeneration ranging from postnatal day 30 (P30) to postnatal month 9.5 (PNM9.5) using immunolabeling for well-known cell- and synapse-specific markers. Following photoreceptor loss, changes occurred progressively from outer to inner retina. Horizontal cells and rod and cone bipolar cells underwent morphological remodeling that included loss of dendrites, cell body migration, and the sprouting of ectopic processes. Gliosis, characterized by translocation of Müller cell bodies to the outer retina and thickening of their processes, was evident by P30 and became more pronounced as degeneration progressed. Following rod degeneration, continued expression of VGluT1 in the outer retina was associated with survival and expression of synaptic proteins by nearby second-order neurons. Rod bipolar cell terminals showed a progressive reduction in size and ectopic bipolar cell processes extended into the inner nuclear layer and ganglion cell layer by PNM3.5. Putative ectopic conventional synapses, likely arising from amacrine cells, were present in the inner nuclear layer by PNM9.5. Despite these changes, the laminar organization of bipolar and amacrine cells and the ON-OFF organization in the inner plexiform layer was largely preserved. Surviving cone and bipolar cell terminals continued to express the appropriate cell-specific presynaptic proteins needed for synaptic function up to PNM9.5. (c) 2010 Wiley-Liss, Inc.

Progression of Neuronal and Synaptic Remodeling in the rd10 Mouse Model of Retinitis Pigmentosa

PubMed Central

Phillips, M. Joseph; Otteson, Deborah C.; Sherry, David M.

2010-01-01

The Pde6brd10 (rd10) mouse has a moderate rate of photoreceptor degeneration and serves as a valuable model for human autosomal recessive retinitis pigmentosa (RP). We evaluated the progression of neuronal remodeling of second- and third-order retinal cells and their synaptic terminals in retinas from Pde6brd10 (rd10) mice at varying stages of degeneration ranging from postnatal day 30 (P30) to postnatal month 9.5 (PNM9.5) using immunolabeling for well known cell- and synapse-specific markers. Following photoreceptor loss, changes occurred progressively from outer to inner retina. Horizontal cells and rod and cone bipolar cells underwent morphological remodeling that included loss of dendrites, cell body migration, and the sprouting of ectopic processes. Gliosis, characterized by translocation of Müller cell bodies to the outer retina and thickening of their processes, was evident by P30 and became more pronounced as degeneration progressed. Following rod degeneration, continued expression of VGluT1 in the outer retina was associated with survival and expression of synaptic proteins by nearby second-order neurons. Rod bipolar cell terminals showed a progressive reduction in size and ectopic bipolar cell processes extended into the inner nuclear layer and ganglion cell layer by PNM3.5. Putative ectopic conventional synapses, likely arising from amacrine cells, were present in the inner nuclear layer by PNM9.5. Despite these changes, the laminar organization of bipolar and amacrine cells and the ON-OFF organization in the inner plexiform layer was largely preserved. Surviving cone and bipolar cell terminals continued to express the appropriate cell-specific presynaptic proteins needed for synaptic function up to PNM9.5. PMID:20394059

SASH1 mediates sensitivity of breast cancer cells to chloropyramine and is associated with prognosis in breast cancer

PubMed Central

Burgess, Joshua T.; Bolderson, Emma; Saunus, Jodi M.; Zhang, Shu-Dong; Reid, Lynne E.; McNicol, Anne Marie; Lakhani, Sunil R.; Cuff, Katharine; Richard, Kerry; Richard, Derek J.; O'Byrne, Kenneth J.

2016-01-01

Expression of the SASH1 protein is reduced in a range of human cancers and has been implicated in apoptotic cancer cell death. This study investigated whether increasing SASH1 expression could be a useful therapeutic strategy in breast cancer. Ectopic SASH1 expression increased apoptosis in 7/8 breast cancer cell lines. Subsequent in silico connectivity screening demonstrated that the clinically approved antihistamine drug, chloropyramine, increased SASH1 mRNA levels. Chloropyramine has previously been shown to have anti-tumour activity in breast cancer in part through modulation of FAK signalling, a pathway also regulated by SASH1. This study demonstrated that chloropyramine increased SASH1 protein levels in breast cancer cells. Consistent with this the agent reduced cell confluency in 7/8 cell lines treated irrespective of their ER status but not apoptosis incompetent MCF7 cells. In contrast SASH1 siRNA-transfected breast cancer cells exhibited reduced chloropyramine sensitivity. The prognostic significance of SASH1 expression was also investigated in two breast cancer cohorts. Expression was associated with favourable outcome in ER-positive cases, but only those of low histological grade/proliferative status. Conversely, we found a very strong inverse association in HER2+ disease irrespective of ER status, and in triple-negative, basal-like cases. Overall, the data suggest that SASH1 is prognostic in breast cancer and could have subtype-dependent effects on breast cancer progression. Pharmacologic induction of SASH1 by chloropyramine treatment of breast cancer warrants further preclinical and clinical investigation. PMID:27637080

SASH1 mediates sensitivity of breast cancer cells to chloropyramine and is associated with prognosis in breast cancer.

PubMed

Burgess, Joshua T; Bolderson, Emma; Saunus, Jodi M; Zhang, Shu-Dong; Reid, Lynne E; McNicol, Anne Marie; Lakhani, Sunil R; Cuff, Katharine; Richard, Kerry; Richard, Derek J; O'Byrne, Kenneth J

2016-11-08

Expression of the SASH1 protein is reduced in a range of human cancers and has been implicated in apoptotic cancer cell death. This study investigated whether increasing SASH1 expression could be a useful therapeutic strategy in breast cancer. Ectopic SASH1 expression increased apoptosis in 7/8 breast cancer cell lines. Subsequent in silico connectivity screening demonstrated that the clinically approved antihistamine drug, chloropyramine, increased SASH1 mRNA levels. Chloropyramine has previously been shown to have anti-tumour activity in breast cancer in part through modulation of FAK signalling, a pathway also regulated by SASH1. This study demonstrated that chloropyramine increased SASH1 protein levels in breast cancer cells. Consistent with this the agent reduced cell confluency in 7/8 cell lines treated irrespective of their ER status but not apoptosis incompetent MCF7 cells. In contrast SASH1 siRNA-transfected breast cancer cells exhibited reduced chloropyramine sensitivity. The prognostic significance of SASH1 expression was also investigated in two breast cancer cohorts. Expression was associated with favourable outcome in ER-positive cases, but only those of low histological grade/proliferative status. Conversely, we found a very strong inverse association in HER2+ disease irrespective of ER status, and in triple-negative, basal-like cases. Overall, the data suggest that SASH1 is prognostic in breast cancer and could have subtype-dependent effects on breast cancer progression. Pharmacologic induction of SASH1 by chloropyramine treatment of breast cancer warrants further preclinical and clinical investigation.

Variation Analysis of Physiological Traits in Betula platyphylla Overexpressing TaLEA-ThbZIP Gene under Salt Stress

PubMed Central

Xiao, Zhenhai; Wang, Fuwei; Li, Shuchun; Zang, Lina; Zheng, Mi; Li, Ying; Qu, Guan-Zheng

2016-01-01

The aim of this study was to determine whether transgenic birch (Betula platyphylla) ectopic overexpressing a late embryogenesis abundant (LEA) gene and a basic leucine zipper (bZIP) gene from the salt-tolerant genus Tamarix (salt cedar) show increased tolerance to salt (NaCl) stress. Co-transfer of TaLEA and ThbZIP in birch under the control of two independent CaMV 35S promoters significantly enhanced salt stress. PCR and northern blot analyses indicated that the two genes were ectopically overexpressed in several dual-gene transgenic birch lines. We compared the effects of salt stress among three transgenic birch lines (L-4, L-5, and L-8) and wild type (WT). In all lines, the net photosynthesis values were higher before salt stress treatment than afterwards. After the salt stress treatment, the transgenic lines L-4 and L-8 showed higher values for photosynthetic traits, chlorophyll fluorescence, peroxidase and superoxide dismutase activities, and lower malondialdehyde and Na+ contents, compared with those in WT and L-5. These different responses to salt stress suggested that the transcriptional level of the TaLEA and ThbZIP genes differed among the transgenic lines, resulting in a variety of genetic and phenotypic effects. The results of this research can provide a theoretical basis for the genetic engineering of salt-tolerant trees. PMID:27802286

A rare case of an ACTH/CRH co-secreting midgut neuroendocrine tumor mimicking Cushing's disease.

PubMed

Streuli, Regina; Krull, Ina; Brändle, Michael; Kolb, Walter; Stalla, Günter; Theodoropoulou, Marily; Enzler-Tschudy, Annette; Bilz, Stefan

2017-01-01

Ectopic ACTH/CRH co-secreting tumors are a very rare cause of Cushing's syndrome and only a few cases have been reported in the literature. Differentiating between Cushing's disease and ectopic Cushing's syndrome may be particularly difficult if predominant ectopic CRH secretion leads to pituitary corticotroph hyperplasia that may mimic Cushing's disease during dynamic testing with both dexamethasone and CRH as well as bilateral inferior petrosal sinus sampling (BIPSS). We present the case of a 24-year-old man diagnosed with ACTH-dependent Cushing's syndrome caused by an ACTH/CRH co-secreting midgut NET. Both high-dose dexamethasone testing and BIPSS suggested Cushing's disease. However, the clinical presentation with a rather rapid onset of cushingoid features, hyperpigmentation and hypokalemia led to the consideration of ectopic ACTH/CRH-secretion and prompted a further workup. Computed tomography (CT) of the abdomen revealed a cecal mass which was identified as a predominantly CRH-secreting neuroendocrine tumor. To the best of our knowledge, this is the first reported case of an ACTH/CRH co-secreting tumor of the cecum presenting with biochemical features suggestive of Cushing's disease. The discrimination between a Cushing's disease and ectopic Cushing's syndrome is challenging and has many caveats.Ectopic ACTH/CRH co-secreting tumors are very rare.Dynamic tests as well as BIPSS may be compatible with Cushing's disease in ectopic CRH-secretion.High levels of CRH may induce hyperplasia of the corticotroph cells in the pituitary. This could be the cause of a preserved pituitary response to dexamethasone and CRH.Clinical features of ACTH-dependent hypercortisolism with rapid development of Cushing's syndrome, hyperpigmentation, high circulating levels of cortisol with associated hypokalemia, peripheral edema and proximal myopathy should be a warning flag of ectopic Cushing's syndrome and lead to further investigations.

Group 3 innate lymphoid cells accumulate and exhibit disease-induced activation in the meninges in EAE.

PubMed

Hatfield, Julianne K; Brown, Melissa A

2015-10-01

Innate lymphoid cells are immune cells that reside in tissues that interface with the external environment and contribute to the first line defense against pathogens. However, they also have roles in promoting chronic inflammation. Here we demonstrate that group 3 ILCs, (ILC3s - CD45+Lin-IL-7Rα+RORγt+), are normal residents of the meninges and exhibit disease-induced accumulation and activation in EAE. In addition to production of the pro-inflammatory cytokines IL-17 and GM-CSF, ILC3s constitutively express CD30L and OX40L, molecules required for memory T cell survival. We show that disease-induced trafficking of transferred wild type T cells to the meninges is impaired in ILC3-deficient Rorc-/- mice. Furthermore, lymphoid tissue inducer cells, a c-kit+ ILC3 subset that promotes ectopic lymphoid follicle development, a hallmark of many autoimmune diseases, are reduced in the meninges of EAE-resistant c-kit mutant Kit(W/Wv) mice. We propose that ILC3s sustain neuroinflammation by supporting T cell survival and reactivation in the meninges. Copyright © 2015 Elsevier Inc. All rights reserved.

Transgenic plants producing the bacterial pheromone N-acyl-homoserine lactone exhibit enhanced resistance to the bacterial phytopathogen Erwinia carotovora.

PubMed

Mäe, A; Montesano, M; Koiv, V; Palva, E T

2001-09-01

Bacterial pheromones, mainly different homoserine lactones, are central to a number of bacterial signaling processes, including those involved in plant pathogenicity. We previously demonstrated that N-oxoacyl-homoserine lactone (OHL) is essential for quorum sensing in the soft-rot phytopathogen Erwinia carotovora. In this pathogen, OHL controls the coordinate activation of genes encoding the main virulence determinants, extracellular plant cell wall degrading enzymes (PCWDEs), in a cell density-dependent manner. We suggest that E. carotovora employ quorum sensing to avoid the premature production of PCWDEs and subsequent activation of plant defense responses. To test whether modulating this sensory system would affect the outcome of a plant-pathogen interaction, we generated transgenic tobacco, producing OHL. This was accomplished by ectopic expression in tobacco of the E. carotovora gene expI, which is responsible for OHL biosynthesis. We show that expI-positive transgenic tobacco lines produced the active pheromone and partially complemented the avirulent phenotype of expI mutants. The OHL-producing tobacco lines exhibited enhanced resistance to infection by wild-type E. carotovora. The results were confirmed by exogenous addition of OHL to wild-type plants, which also resulted in increased resistance to E. carotovora.

Ectopic expression of Arabidopsis Target of Rapamycin (AtTOR) improves water-use efficiency and yield potential in rice

NASA Astrophysics Data System (ADS)

Bakshi, Achala; Moin, Mazahar; Kumar, M. Udaya; Reddy, Aramati Bindu Madhava; Ren, Maozhi; Datla, Raju; Siddiq, E. A.; Kirti, P. B.

2017-02-01

The target of Rapamycin (TOR) present in all eukaryotes is a multifunctional protein, regulating growth, development, protein translation, ribosome biogenesis, nutrient, and energy signaling. In the present study, ectopic expression of TOR gene of Arabidopsis thaliana in a widely cultivated indica rice resulted in enhanced plant growth under water-limiting conditions conferring agronomically important water-use efficiency (WUE) trait. The AtTOR high expression lines of rice exhibited profuse tillering, increased panicle length, increased plant height, high photosynthetic efficiency, chlorophyll content and low Δ13C. Δ13C, which is inversely related to high WUE, was as low as 17‰ in two AtTOR high expression lines. These lines were also insensitive to the ABA-mediated inhibition of seed germination. The significant upregulation of 15 stress-specific genes in high expression lines indicates their contribution to abiotic stress tolerance. The constitutive expression of AtTOR is also associated with significant transcriptional upregulation of putative TOR complex-1 components, OsRaptor and OsLST8. Glucose-mediated transcriptional activation of AtTOR gene enhanced lateral root formation. Taken together, our findings indicate that TOR, in addition to its multiple cellular functions, also plays an important role in response to abiotic stress and potentially enhances WUE and yield related attributes.

Regulation of D-cyclin translation inhibition in myeloma cells treated with mTOR inhibitors: Rationale for combined treatment with ERK inhibitors and rapamycin

PubMed Central

Frost, Patrick; Shi, Yijiang; Hoang, Bao; Gera, Joseph; Lichtenstein, Alan

2009-01-01

We have shown that heightened AKT activity sensitized multiple myeloma (MM) cells to the anti-tumor effects of the mTOR-inhibitor, CCI-779. To test the mechanism of AKT’s regulatory role, we stably transfected U266 MM cell lines with an activated AKT allele or empty vector. The AKT-transfected cells were more sensitive to cytostasis induced in vitro by rapamycin or in vivo by its analog, CCI-779, whereas cells with quiescent AKT were resistant. The ability of mTOR inhibitors to downregulate D-cyclin expression was significantly greater in AKT-transfected MM cells, due in part, to AKT’s ability to curtail cap-independent translation and internal ribosome entry site (IRES) activity of D-cyclin transcripts. Similar AKT-dependent regulation of rapamycin responsiveness was demonstrated in a second myeloma model: the PTEN-null OPM-2 cell line transfected with wild type PTEN. As ERK/p38 activity facilitates IRES-mediated translation of some transcripts, we investigated ERK/p38 as regulators of AKT-dependent effects on rapamycin sensitivity. AKT-transfected U266 cells demonstrated significantly decreased ERK and p38 activity. However, only an ERK inhibitor prevented D-cyclin IRES activity in resistant “low AKT” myeloma cells. Furthermore, the ERK inhibitor successfully sensitized myeloma cells to rapamycin in terms of down regulated D-cyclin protein expression and G1 arrest. However, ectopic over-expression of an activated MEK gene did not increase cap-independent translation of D-cyclin in “high AKT” myeloma cells indicating that MEK/ERK activity was required but not sufficient for activation of the IRES. These data support a scenario where heightened AKT activity down-regulates D-cyclin IRES function in MM cells and ERK facilitates activity. PMID:19139116

MicroRNA-128b suppresses tumor growth and promotes apoptosis by targeting A2bR in gastric cancer

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

Wang, Ping; Guo, Xueyan; Zong, Wei

2015-11-27

MicroRNAs (miRNAs) play crucial roles in the development and progression of human cancers, including gastric cancer (GC). The discovery of miRNAs may provide a new and powerful tool for studying the mechanism, diagnosis, and treatment of GC. In this study, we aimed to investigate the role and mechanism of miR-128b in the development and progression of GC. Quantitative real-time PCR (qRT-PCR) was used to measure the expression level of miR-128b in GC tissues and cell lines. We found that miR-128b was significantly down-regulated in GC tissues and cell lines. In addition, over-expression of miR-128b inhibited GC cell proliferation, migration andmore » invasion of GC cells in vitro. Gain-of-function in vitro experiments further showed that the miR-128b mimic significantly promoted GC cell apoptosis. Subsequent dual-luciferase reporter assay identified one of the proto-oncogene A2bR as direct target of miR-128b. Therefore, our results indicate that miR-128b is a proto-oncogene miRNA that can suppresses GC proliferation and migration through down-regulation of the oncogene gene A2bR. Taken together, our results indicate that miR-128b could serve as a potential diagnostic biomarker and therapeutic option for human GC in the near future. - Highlights: • The expression of MiR-128b is significantly down-regulated in GC tissues and cell lines. • Ectopic expression of miR-128b directly affects cell proliferation, migration and invasion in vitro. • Overexpression of miR-128b increases apoptosis in GC cells. • A2bR is a candidate target gene of miR-128b. • MiR-128b represses cell proliferation, migration and invasion and promotes apoptosis by targeting A2bR in GC.« less

IL-27 triggers IL-10 production in Th17 cells via a c-Maf/RORγt/Blimp-1 signal to promote the progression of endometriosis

PubMed Central

Chang, Kai-Kai; Liu, Li-Bing; Jin, Li-Ping; Zhang, Bing; Mei, Jie; Li, Hui; Wei, Chun-Yan; Zhou, Wen-Jie; Zhu, Xiao-Yong; Shao, Jun; Li, Da-Jin; Li, Ming-Qing

2017-01-01

Endometriosis is an estrogen-dependent inflammatory disease. The anti-inflammatory cytokine IL-10 is also increased in endometriosis. IL-10 production by Th17 cells is critical for limiting autoimmunity and inflammatory responses. However, the mechanism of inducing IL-10-producing Th17 cells is still largely unknown. The present study investigated the differentiation mechanism and role of IL-10-producing Th17 cells in endometriosis. Here, we report that IL-10+Th17 cells are significantly increased in the peritoneal fluid of women with endometriosis, along with an elevation of IL-27, IL-6 and TGF-β. Compared with peripheral CD4+ T cells, endometrial CD4+ T cells highly expressed IL-27 receptors, especially the ectopic endometrium. Under external (2,3,7,8-tetrachlorodibenzo-p-dioxin, TCDD) and local (estrogen, IL-6 and TGF-β) environmental regulation, IL-27 from macrophages and endometrial stromal cells (ESCs) induces IL-10 production in Th17 cells in vitro and in vivo. This process may be mediated through the interaction between c-musculoaponeurotic fibrosarconna (c-Maf) and retinoic acid-related orphan receptor gamma t (RORγt), and associated with the upregulation of downstream B lymphocyte-induced maturation protein-1 (Blimp-1). IL-10+Th17 cells, in turn, stimulate the proliferation and implantation of ectopic lesions and accelerate the progression of endometriosis. These results suggest that IL-27 is a pivotal regulator in endometriotic immune tolerance by triggering Th17 cells to produce IL-10 and promoting the rapid growth and implantation of ectopic lesions. This finding provides a scientific basis for potential therapeutic strategies aimed at preventing the development of endometriosis, especially for patients with high levels of IL-10+Th17 cells. PMID:28300844

M1 muscarinic receptor activation mediates cell death in M1-HEK293 cells.

PubMed

Graham, E Scott; Woo, Kerhan K; Aalderink, Miranda; Fry, Sandie; Greenwood, Jeffrey M; Glass, Michelle; Dragunow, Mike

2013-01-01

HEK293 cells have been used extensively to generate stable cell lines to study G protein-coupled receptors, such as muscarinic acetylcholine receptors (mAChRs). The activation of M1 mAChRs in various cell types in vitro has been shown to be protective. To further investigate M1 mAChR-mediated cell survival, we generated stable HEK293 cell-lines expressing the human M1 mAChR. M1 mAChRs were efficiently expressed at the cell surface and efficiently internalised within 1 h by carbachol. Carbachol also induced early signalling cascades similar to previous reports. Thus, ectopically expressed M1 receptors behaved in a similar fashion to the native receptor over short time periods of analysis. However, substantial cell death was observed in HEK293-M1 cells within 24 h after carbachol application. Death was only observed in HEK cells expressing M1 receptors and fully blocked by M1 antagonists. M1 mAChR-stimulation mediated prolonged activation of the MEK-ERK pathway and resulted in prolonged induction of the transcription factor EGR-1 (>24 h). Blockade of ERK signalling with U0126 did not reduce M1 mAChR-mediated cell-death significantly but inhibited the acute induction of EGR-1. We investigated the time-course of cell death using time-lapse microscopy and xCELLigence technology. Both revealed the M1 mAChR cytotoxicity occurs within several hours of M1 activation. The xCELLigence assay also confirmed that the ERK pathway was not involved in cell-death. Interestingly, the MEK blocker did reduce carbachol-mediated cleaved caspase 3 expression in HEK293-M1 cells. The HEK293 cell line is a widely used pharmacological tool for studying G-protein coupled receptors, including mAChRs. Our results highlight the importance of investigating the longer term fate of these cells in short term signalling studies. Identifying how and why activation of the M1 mAChR signals apoptosis in these cells may lead to a better understanding of how mAChRs regulate cell-fate decisions.

JMJD3 suppresses stem cell-like characteristics in breast cancer cells by downregulation of Oct4 independently of its demethylase activity.

PubMed

Xun, Jing; Wang, Dekun; Shen, Long; Gong, Junbo; Gao, Ruifang; Du, Lingfang; Chang, Antao; Song, Xiangrong; Xiang, Rong; Tan, Xiaoyue

2017-03-28

Epigenetic regulator JMJD3 plays an important role in both tumor progression and somatic cell reprogramming. Here, we explored the effect of JMJD3 on the stem cell-like characteristics of breast cancer and its underlying mechanism involving stemness-related transcription factor Oct4. Our data revealed that, in breast cancer cells lines and an orthotopic xenograph mouse model of breast cancer, ectopic overexpression of JMJD3 suppressed stem cell-like characteristics of breast cancer cells, whereas knockdown of JMJD3 promoted these characteristics. Oct4 mediated the suppressive effects of JMJD3 on the stemness of breast cancer cells. The inhibitory effect of JMJD3 on Oct4 was independent of demethylase activity, but mediated via degradation of PHF20. Furthermore, we applied an agonist of the vitamin D receptor, paricalcitol, and found that it induced JMJD3 in breast cancer cells. Our data showed that administration of paricalcitol suppressed stem cell-like characteristics and Oct4 expression. Taken together, JMJD3 inhibits the stem cell-like characteristics in breast cancer by suppression of stemness factor Oct4 in a PHF20-dependent manner. Administration of paricalcitol leads to upregulation of JMJD3 that suppresses Oct4 expression and the stem cell-like characteristics in breast cancer.

The homeodomain transcription factor Cdx1 does not behave as an oncogene in normal mouse intestine.

PubMed

Crissey, Mary Ann S; Guo, Rong-Jun; Fogt, Franz; Li, Hong; Katz, Jonathan P; Silberg, Debra G; Suh, Eun Ran; Lynch, John P

2008-01-01

The Caudal-related homeobox genes Cdx1 and Cdx2 are intestine-specific transcription factors that regulate differentiation of intestinal cell types. Previously, we have shown Cdx1 to be antiproliferative and to promote cell differentiation. However, other studies have suggested that Cdx1 may be an oncogene. To test for oncogenic behavior, we used the murine villin promoter to ectopically express Cdx1 in the small intestinal villi and colonic surface epithelium. No changes in intestinal architecture, cell differentiation, or lineage selection were observed with expression of the transgene. Classic oncogenes enhance proliferation and induce tumors when ectopically expressed. However, the Cdx1 transgene neither altered intestinal proliferation nor induced spontaneous intestinal tumors. In a murine model for colitis-associated cancer, the Cdx1 transgene decreased, rather than increased, the number of adenomas that developed. In the polyps, the expression of the endogenous and the transgenic Cdx1 proteins was largely absent, whereas endogenous Villin expression was retained. This suggests that transgene silencing was specific and not due to a general Villin inactivation. In conclusion, neither the ectopic expression of Cdx1 was associated with changes in intestinal cell proliferation or differentiation nor was there increased intestinal cancer susceptibility. Our results therefore suggest that Cdx1 is not an oncogene in normal intestinal epithelium.

Cutting Edge: Inflammasome Activation in Primary Human Macrophages Is Dependent on Flagellin

PubMed Central

Kortmann, Jens; Brubaker, Sky W.

2015-01-01

Murine NLR family, apoptosis inhibitory protein (Naip)1, Naip2, and Naip5/6 are host sensors that detect the cytosolic presence of needle and rod proteins from bacterial type III secretion systems and flagellin, respectively. Previous studies using human-derived macrophage-like cell lines indicate that human macrophages sense the cytosolic needle protein, but not bacterial flagellin. In this study, we show that primary human macrophages readily sense cytosolic flagellin. Infection of primary human macrophages with Salmonella elicits robust cell death and IL-1β secretion that is dependent on flagellin. We show that flagellin detection requires a full-length isoform of human Naip. This full-length Naip isoform is robustly expressed in primary macrophages from healthy human donors, but it is drastically reduced in monocytic tumor cells, THP-1, and U937, rendering them insensitive to cytosolic flagellin. However, ectopic expression of full-length Naip rescues the ability of U937 cells to sense flagellin. In conclusion, human Naip functions to activate the inflammasome in response to flagellin, similar to murine Naip5/6. PMID:26109648

RNAi-Dependent and Independent Control of LINE1 Accumulation and Mobility in Mouse Embryonic Stem Cells

PubMed Central

Ciaudo, Constance; Jay, Florence; Okamoto, Ikuhiro; Chen, Chong-Jian; Sarazin, Alexis; Servant, Nicolas; Barillot, Emmanuel; Heard, Edith; Voinnet, Olivier

2013-01-01

In most mouse tissues, long-interspersed elements-1 (L1s) are silenced via methylation of their 5′-untranslated regions (5′-UTR). A gradual loss-of-methylation in pre-implantation embryos coincides with L1 retrotransposition in blastocysts, generating potentially harmful mutations. Here, we show that Dicer- and Ago2-dependent RNAi restricts L1 accumulation and retrotransposition in undifferentiated mouse embryonic stem cells (mESCs), derived from blastocysts. RNAi correlates with production of Dicer-dependent 22-nt small RNAs mapping to overlapping sense/antisense transcripts produced from the L1 5′-UTR. However, RNA-surveillance pathways simultaneously degrade these transcripts and, consequently, confound the anti-L1 RNAi response. In Dicer−/− mESC complementation experiments involving ectopic Dicer expression, L1 silencing was rescued in cells in which microRNAs remained strongly depleted. Furthermore, these cells proliferated and differentiated normally, unlike their non-complemented counterparts. These results shed new light on L1 biology, uncover defensive, in addition to regulatory roles for RNAi, and raise questions on the differentiation defects of Dicer−/− mESCs. PMID:24244175

Stage- and subunit-specific functions of polycomb repressive complex 2 in bladder urothelial formation and regeneration

PubMed Central

Guo, Chunming; Balsara, Zarine R.

2017-01-01

ABSTRACT Urothelium is the protective lining of the urinary tract. The mechanisms underlying urothelial formation and maintenance are largely unknown. Here, we report the stage-specific roles of PRC2 epigenetic regulators in embryonic and adult urothelial progenitors. Without Eed, the obligatory subunit of PRC2, embryonic urothelial progenitors demonstrate reduced proliferation with concomitant dysregulation of genes including Cdkn2a (p16), Cdkn2b (p15) and Shh. These mutants display premature differentiation of keratin 5-positive (Krt5+) basal cells and ectopic expression of squamous-like differentiation markers. Deletion of Ezh2, the major enzymatic component of PRC2, causes upregulation of Upk3a+ superficial cells. Unexpectedly, Eed and Eed/Ezh2 double mutants exhibit delayed superficial cell differentiation. Furthermore, Eed regulates the proliferative and regenerative capacity of adult urothelial progenitors and prevents precocious differentiation. Collectively, these findings uncover the epigenetic mechanism by which PRC2 controls urothelial progenitor cell fate and the timing of differentiation, and further suggest an epigenetic basis of urothelial maintenance and regeneration. PMID:28049658

The homeobox gene mirror links EGF signalling to embryonic dorso-ventral axis formation through notch activation.

PubMed

Jordan, K C; Clegg, N J; Blasi, J A; Morimoto, A M; Sen, J; Stein, D; McNeill, H; Deng, W M; Tworoger, M; Ruohola-Baker, H

2000-04-01

Recent studies in vertebrates and Drosophila melanogaster have revealed that Fringe-mediated activation of the Notch pathway has a role in patterning cell layers during organogenesis. In these processes, a homeobox-containing transcription factor is responsible for spatially regulating fringe (fng) expression and thus directing activation of the Notch pathway along the fng expression border. Here we show that this may be a general mechanism for patterning epithelial cell layers. At three stages in Drosophila oogenesis, mirror (mirr) and fng have complementary expression patterns in the follicle-cell epithelial layer, and at all three stages loss of mirr enlarges, and ectopic expression of mirr restricts, fng expression, with consequences for follicle-cell patterning. These morphological changes are similar to those caused by Notch mutations. Ectopic expression of mirr in the posterior follicle cells induces a stripe of rhomboid (rho) expression and represses pipe (pip), a gene with a role in the establishment of the dorsal-ventral axis, at a distance. Ectopic Notch activation has a similar long-range effect on pip. Our results suggest that Mirror and Notch induce secretion of diffusible morphogens and we have identified TGF-beta (encoded by dpp) as such a molecule in germarium. We also found that mirr expression in dorsal follicle cells is induced by the EGF-receptor (EGFR) pathway and that mirr then represses pip expression in all but the ventral follicle cells, connecting EGFR activation in the dorsal follicle cells to repression of pip in the dorsal and lateral follicle cells. Our results suggest that the differentiation of ventral follicle cells is not a direct consequence of germline signalling, but depends on long-range signals from dorsal follicle cells, and provide a link between early and late events in Drosophila embryonic dorsal-ventral axis formation.

Capture of microRNA-bound mRNAs identifies the tumor suppressor miR-34a as a regulator of growth factor signaling.

PubMed

Lal, Ashish; Thomas, Marshall P; Altschuler, Gabriel; Navarro, Francisco; O'Day, Elizabeth; Li, Xiao Ling; Concepcion, Carla; Han, Yoon-Chi; Thiery, Jerome; Rajani, Danielle K; Deutsch, Aaron; Hofmann, Oliver; Ventura, Andrea; Hide, Winston; Lieberman, Judy

2011-11-01

A simple biochemical method to isolate mRNAs pulled down with a transfected, biotinylated microRNA was used to identify direct target genes of miR-34a, a tumor suppressor gene. The method reidentified most of the known miR-34a regulated genes expressed in K562 and HCT116 cancer cell lines. Transcripts for 982 genes were enriched in the pull-down with miR-34a in both cell lines. Despite this large number, validation experiments suggested that ~90% of the genes identified in both cell lines can be directly regulated by miR-34a. Thus miR-34a is capable of regulating hundreds of genes. The transcripts pulled down with miR-34a were highly enriched for their roles in growth factor signaling and cell cycle progression. These genes form a dense network of interacting gene products that regulate multiple signal transduction pathways that orchestrate the proliferative response to external growth stimuli. Multiple candidate miR-34a-regulated genes participate in RAS-RAF-MAPK signaling. Ectopic miR-34a expression reduced basal ERK and AKT phosphorylation and enhanced sensitivity to serum growth factor withdrawal, while cells genetically deficient in miR-34a were less sensitive. Fourteen new direct targets of miR-34a were experimentally validated, including genes that participate in growth factor signaling (ARAF and PIK3R2) as well as genes that regulate cell cycle progression at various phases of the cell cycle (cyclins D3 and G2, MCM2 and MCM5, PLK1 and SMAD4). Thus miR-34a tempers the proliferative and pro-survival effect of growth factor stimulation by interfering with growth factor signal transduction and downstream pathways required for cell division.

Enhanced epithelial to mesenchymal transition (EMT) and upregulated MYC in ectopic lesions contribute independently to endometriosis.

PubMed

Proestling, Katharina; Birner, Peter; Gamperl, Susanne; Nirtl, Nadine; Marton, Erika; Yerlikaya, Gülen; Wenzl, Rene; Streubel, Berthold; Husslein, Heinrich

2015-07-22

Epithelial to mesenchymal transition (EMT) is a process in which epithelial cells lose polarity and cell-to-cell contacts and acquire the migratory and invasive abilities of mesenchymal cells. These abilities are thought to be prerequisites for the establishment of endometriotic lesions. A hallmark of EMT is the functional loss of E-cadherin (CDH1) expression in epithelial cells. TWIST1, a transcription factor that represses E-cadherin transcription, is among the EMT inducers. SNAIL, a zinc-finger transcription factor, and its close relative SLUG have similar properties to TWIST1 and are thus also EMT inducers. MYC, which is upregulated by estrogens in the uterus by an estrogen response cis-acting element (ERE) in its promoter, is associated with proliferation in endometriosis. The role of EMT and proliferation in the pathogenesis of endometriosis was evaluated by analyzing TWIST1, CDH1 and MYC expression. CDH1, TWIST1, SNAIL and SLUG mRNA expression was analyzed by qRT-PCR from 47 controls and 74 patients with endometriosis. Approximately 42 ectopic and 62 eutopic endometrial tissues, of which 30 were matched samples, were collected during the same surgical procedure. We evaluated TWIST1 and MYC protein expression by immunohistochemistry (IHC) in the epithelial and stromal tissue of 69 eutopic and 90 ectopic endometrium samples, of which 49 matched samples were analyzed from the same patient. Concordant expression of TWIST1/SNAIL/SLUG and CDH1 but also of TWIST1 and MYC was analyzed. We found that TWIST1, SNAIL and SLUG are overexpressed (p < 0.001, p = 0.016 and p < 0.001) in endometriosis, while CDH1 expression was concordantly reduced in these samples (p < 0.001). Similar to TWIST1, the epithelial expression of MYC was also significantly enhanced in ectopic endometrium compared to eutopic tissues (p = 0.008). We found exclusive expression of either TWIST1 or MYC in the same samples (p = 0.003). Epithelial TWIST1 is overexpressed in endometriosis and may contribute to the formation of endometriotic lesions by inducing epithelial to mesenchymal transition, as CDH1 was reduced in ectopic lesions. We found exclusive expression of either TWIST1 or MYC in the same samples, indicating that EMT and proliferation contribute independently of each other to the formation of endometriotic lesions.

Short Vegetative Phase-Like MADS-Box Genes Inhibit Floral Meristem Identity in Barley1[W][OA

PubMed Central

Trevaskis, Ben; Tadege, Million; Hemming, Megan N.; Peacock, W. James; Dennis, Elizabeth S.; Sheldon, Candice

2007-01-01

Analysis of the functions of Short Vegetative Phase (SVP)-like MADS-box genes in barley (Hordeum vulgare) indicated a role in determining meristem identity. Three SVP-like genes are expressed in vegetative tissues of barley: Barley MADS1 (BM1), BM10, and Vegetative to Reproductive Transition gene 2. These genes are induced by cold but are repressed during floral development. Ectopic expression of BM1 inhibited spike development and caused floral reversion in barley, with florets at the base of the spike replaced by tillers. Head emergence was delayed in plants that ectopically express BM1, primarily by delayed development after the floral transition, but expression levels of the barley VRN1 gene (HvVRN1) were not affected. Ectopic expression of BM10 inhibited spike development and caused partial floral reversion, where florets at the base of the spike were replaced by inflorescence-like structures, but did not affect heading date. Floral reversion occurred more frequently when BM1 and BM10 ectopic expression lines were grown in short-day conditions. BM1 and BM10 also inhibited floral development and caused floral reversion when expressed in Arabidopsis (Arabidopsis thaliana). We conclude that SVP-like genes function to suppress floral meristem identity in winter cereals. PMID:17114273

Loss of PodJ in Agrobacterium tumefaciens Leads to Ectopic Polar Growth, Branching, and Reduced Cell Division

PubMed Central

Anderson-Furgeson, James C.; Zupan, John R.; Grangeon, Romain

2016-01-01

ABSTRACT Agrobacterium tumefaciens is a rod-shaped Gram-negative bacterium that elongates by unipolar addition of new cell envelope material. Approaching cell division, the growth pole transitions to a nongrowing old pole, and the division site creates new growth poles in sibling cells. The A. tumefaciens homolog of the Caulobacter crescentus polar organizing protein PopZ localizes specifically to growth poles. In contrast, the A. tumefaciens homolog of the C. crescentus polar organelle development protein PodJ localizes to the old pole early in the cell cycle and accumulates at the growth pole as the cell cycle proceeds. FtsA and FtsZ also localize to the growth pole for most of the cell cycle prior to Z-ring formation. To further characterize the function of polar localizing proteins, we created a deletion of A. tumefaciens podJ (podJAt). ΔpodJAt cells display ectopic growth poles (branching), growth poles that fail to transition to an old pole, and elongated cells that fail to divide. In ΔpodJAt cells, A. tumefaciens PopZ-green fluorescent protein (PopZAt-GFP) persists at nontransitioning growth poles postdivision and also localizes to ectopic growth poles, as expected for a growth-pole-specific factor. Even though GFP-PodJAt does not localize to the midcell in the wild type, deletion of podJAt impacts localization, stability, and function of Z-rings as assayed by localization of FtsA-GFP and FtsZ-GFP. Z-ring defects are further evidenced by minicell production. Together, these data indicate that PodJAt is a critical factor for polar growth and that ΔpodJAt cells display a cell division phenotype, likely because the growth pole cannot transition to an old pole. IMPORTANCE How rod-shaped prokaryotes develop and maintain shape is complicated by the fact that at least two distinct species-specific growth modes exist: uniform sidewall insertion of cell envelope material, characterized in model organisms such as Escherichia coli, and unipolar growth, which occurs in several alphaproteobacteria, including Agrobacterium tumefaciens. Essential components for unipolar growth are largely uncharacterized, and the mechanism constraining growth to one pole of a wild-type cell is unknown. Here, we report that the deletion of a polar development gene, podJAt, results in cells exhibiting ectopic polar growth, including multiple growth poles and aberrant localization of cell division and polar growth-associated proteins. These data suggest that PodJAt is a critical factor in normal polar growth and impacts cell division in A. tumefaciens. PMID:27137498

Transcriptional Regulation of Type 11 17β-Hydroxysteroid Dehydrogenase Expression in Prostate Cancer Cells

PubMed Central

Rotinen, Mirja; Villar, Joaquín; Celay, Jon; Serrano, Irantzu; Notario, Vicente; Encío, Ignacio

2011-01-01

Type 11 Hydroxysteroid (17-beta) dehydrogenase (HSD17B11) catalyzes the conversion of 5α-androstan-3α,17β-diol into androsterone suggesting that it may play an important role in androgen metabolism. We previously described that overexpression of C/EBPα or C/EBPβ induced HSD17B11 expression in HepG2 cells but this process was not mediated by the CCAAT boxes located within its proximal promoter region. Here, we study HSD17B11 transcriptional regulation in prostate cancer (PC) cells. Transfection experiments showed that the region −107/+18 is sufficient for promoter activity in PC cells. Mutagenesis analysis indicated that Sp1 and C/EBP binding sites found in this region are essential for promoter activity. Additional experiments demonstrated that ectopic expression of Sp1 and C/EBPα upregulated HSD17B11 expression only in PC cell lines. Through DAPA and ChIP assays, specific recruitment of Sp1 and C/EBPα to the HSD17B11 promoter was detected. These results show that HSD17B11 transcription in PC cells is regulated by Sp1 and C/EBPα. PMID:21549806

Star-PAP, a poly(A) polymerase, functions as a tumor suppressor in an orthotopic human breast cancer model

PubMed Central

Yu, C; Gong, Y; Zhou, H; Wang, M; Kong, L; Liu, J; An, T; Zhu, H; Li, Y

2017-01-01

Star-PAP is a noncanonical poly(A) polymerase and required for the expression of a select set of mRNAs. However, the pathological role of Star-PAP in cancer largely remains unknown. In this study, we observed decreased expression of Star-PAP in breast cancer cell lines and tissues. Ectopic Star-PAP expression inhibited proliferation as well as colony-forming ability of breast cancer cells. In breast cancer patients, high levels of Star-PAP correlated with an improved prognosis. Moreover, by regulating the expression of BIK (BCL2-interacting killer), Star-PAP induced apoptosis of breast cancer cells through the mitochondrial pathway. The growth of breast cancer xenografts in NOD/SCID mice was also inhibited by the doxycycline-induced Star-PAP overexpression. Furthermore, Star-PAP sensitized breast cancer cells to chemotherapy drugs both in vitro and in vivo. In mammary epithelial cells, Star-PAP knockdown partially transformed these cells and induced them to undergo epithelial–mesenchymal transition (EMT). These findings suggested that Star-PAP possesses tumor-suppressing activity and can be a valuable target for developing new cancer therapeutic strategies. PMID:28151486

The Bladder Tumor Suppressor Protein TERE1 (UBIAD1)Modulates Cell Cholesterol: Implications for Tumor Progression

PubMed Central

McGarvey, Terry; Wang, Huiyi; Lal, Priti; Puthiyaveettil, Raghunath; Tomaszewski, John; Sepulveda, Jorge; Labelle, Ed; Weiss, Jayne S.; Nickerson, Michael L.; Kruth, Howard S.; Brandt, Wolfgang; Wessjohann, Ludger A.; Malkowicz, S. Bruce

2011-01-01

Convergent evidence implicates the TERE1 protein in human bladder tumor progression and lipid metabolism. Previously, reduced TERE1 expression was found in invasive urologic cancers and inhibited cell growth upon re-expression. A role in lipid metabolism was suggested by TERE1 binding to APOE, a cholesterol carrier, and to TBL2, a candidate protein in triglyceride disorders. Natural TERE1 mutations associate with Schnyder's corneal dystrophy, characterized by lipid accumulation. TERE1 catalyzes menaquinone synthesis, known to affect cholesterol homeostasis. To explore this relationship, we altered TERE1 and TBL2 dosage via ectopic expression and interfering RNA and measured cholesterol by Amplex red. Protein interactions of wild-type and mutant TERE1 with GST-APOE were evaluated by binding assays and molecular modeling. We conducted a bladder tumor microarray TERE1 expression analysis and assayed tumorigenicity of J82 cells ectopically expressing TERE1. TERE1 expression was reduced in a third of invasive specimens. Ectopic TERE1 expression in J82 bladder cancer cells dramatically inhibited nude mouse tumorigenesis. TERE1 and TBL2 proteins inversely modulated cellular cholesterol in HEK293 and bladder cancer cells from 20% to 50%. TERE1 point mutations affected APOE interactions, and resulted in cholesterol levels that differed from wild type. Elevated tumor cell cholesterol is known to affect apoptosis and growth signaling; thus, loss of TERE1 in invasive bladder cancer may represent a defect in menaquinone-mediated cholesterol homeostasis that contributes to progression. PMID:21740188

Development of functional ectopic compound eyes in scarabaeid beetles by knockdown of orthodenticle.

PubMed

Zattara, Eduardo E; Macagno, Anna L M; Busey, Hannah A; Moczek, Armin P

2017-11-07

Complex traits like limbs, brains, or eyes form through coordinated integration of diverse cell fates across developmental space and time, yet understanding how complexity and integration emerge from uniform, undifferentiated precursor tissues remains limited. Here, we use ectopic eye formation as a paradigm to investigate the emergence and integration of novel complex structures following massive ontogenetic perturbation. We show that down-regulation via RNAi of a single head patterning gene- orthodenticle -induces ectopic structures externally resembling compound eyes at the middorsal adult head of both basal and derived scarabaeid beetle species (Onthophagini and Oniticellini). Scanning electron microscopy documents ommatidial organization of these induced structures, while immunohistochemistry reveals the presence of rudimentary ommatidial lenses, crystalline cones, and associated neural-like tissue within them. Further, RNA-sequencing experiments show that after orthodenticle down-regulation, the transcriptional signature of the middorsal head-the location of ectopic eye induction-converges onto that of regular compound eyes, including up-regulation of several retina-specific genes. Finally, a light-aversion behavioral assay to assess functionality reveals that ectopic compound eyes can rescue the ability to respond to visual stimuli when wild-type eyes are surgically removed. Combined, our results show that knockdown of a single gene is sufficient for the middorsal head to acquire the competence to ectopically generate a functional compound eye-like structure. These findings highlight the buffering capacity of developmental systems, allowing massive genetic perturbations to be channeled toward orderly and functional developmental outcomes, and render ectopic eye formation a widely accessible paradigm to study the evolution of complex systems. Published under the PNAS license.

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.

Frequent and Focal FGFR1 Amplification Associates With Therapeutically Tractable FGFR1 Dependency in Squamous-cell Lung Cancer

PubMed Central

Weiss, Jonathan; Sos, Martin L.; Seidel, Danila; Peifer, Martin; Zander, Thomas; Heuckmann, Johannes M.; Ullrich, Roland T.; Menon, Roopika; Maier, Sebastian; Soltermann, Alex; Moch, Holger; Wagener, Patrick; Fischer, Florian; Heynck, Stefanie; Koker, Mirjam; Schöttle, Jakob; Leenders, Frauke; Gabler, Franziska; Dabow, Ines; Querings, Silvia; Heukamp, Lukas C.; Balke-Want, Hyatt; Ansén, Sascha; Rauh, Daniel; Baessmann, Ingelore; Altmüller, Janine; Wainer, Zoe; Conron, Matthew; Wright, Gavin; Russell, Prudence; Solomon, Ben; Brambilla, Elisabeth; Brambilla, Christian; Lorimier, Philippe; Sollberg, Steinar; Brustugun, Odd Terje; Engel-Riedel, Walburga; Ludwig, Corinna; Petersen, Iver; Sänger, Jörg; Clement, Joachim; Groen, Harry; Timens, Wim; Sietsma, Hannie; Thunnissen, Erik; Smit, Egbert; Heideman, Daniëlle; Cappuzzo, Federico; Ligorio, Claudia; Damiani, Stefania; Hallek, Michael; Beroukhim, Rameen; Pao, William; Klebl, Bert; Baumann, Matthias; Buettner, Reinhard; Ernestus, Karen; Stoelben, Erich; Wolf, Jürgen; Nürnberg, Peter; Perner, Sven; Thomas, Roman K.

2014-01-01

Lung cancer remains one of the leading causes for cancer-related death in developed countries. In lung adenocarcinomas, EGFR mutations and EML4-ALK fusions are associated with response to EGFR and ALK inhibition. By contrast, therapeutically exploitable genetic alterations have been lacking in squamous-cell lung cancer. We conducted a systematic search for alterations that are therapeutically amenable and performed high-resolution gene-copy number analyses in a set of 232 lung cancer specimens. We identified frequent and focal FGFR1 amplification in squamous-cell lung cancer (n=155), but not in other lung cancer subtypes, and confirmed its presence in an independent cohort of squamous-cell lung cancer samples employing FISH (22% of cases). Using cell-based screening with the FGFR inhibitor (PD173074) in a large (n=83) panel of lung cancer cell lines, we demonstrated that this compound inhibited growth (p=0.0002) and induced apoptosis (p=0.008) specifically in those lung cancer cells carrying amplified FGFR1. We validated the dependency on FGFR1 of FGFR1-amplified cell lines by knockdown of FGFR1 and by ectopic expression of a resistance allele of FGFR1 (FGFR1V561M), which rescued FGFR1-amplified cells from PD173074-mediated cytotoxicity. Finally we showed that inhibition of FGFR1 with a small molecule led to significant tumor shrinkage in vivo. Focal FGFR1 amplification is common in squamous-cell lung cancer and associated with tumor growth and survival, suggesting that FGFR inhibitors may be a viable therapeutic option in this cohort of patients. PMID:21160078

Thiazolidinedione treatment and constitutive-PPARγ activation induces ectopic adipogenesis and promotes age-related thymic involution

PubMed Central

Youm, Yun-Hee; Yang, Hyunwon; Amin, Raj; Smith, Steven R.; Leff, Todd; Dixit, Vishwa Deep

2010-01-01

Age-related thymic involution is characterized by reduction in T cell production together with ectopic adipocyte development within the hematopoietic and thymic niches. PPARγ is required for adipocyte development, glucose homeostasis and is a target for several insulin-sensitizing drugs. Our prior studies showed that age-related elevation of PPARγ expression in thymic stromal cells is associated with thymic involution. Here, using clinically relevant pharmacological and genetic manipulations in mouse models, we provide evidence that activation of PPARγ leads to reduction in thymopoiesis. Treatment of aged mice with anti-hyperglycemic PPARγ-ligand class of Thiazolidinedione drug, Rosiglitazone caused robust thymic expression of classical pro-adipogenic transcripts. Rosiglitazone reduced thymic cellularity, lowered the naïve T cell number and T cell receptor excision circles (TRECs) indicative of compromised thymopoiesis. To directly investigate whether PPARγ activation induces thymic involution, we created transgenic mice with constitutive-active PPARγ (CA-PPARg) fusion protein in cells of adipogenic lineage. Importantly, CA-PPARγ transgene was expressed in thymus and in Fibroblast Specific Protein-1/S100A4 (FSP1+) cells, a marker of secondary mesenchymal cells. The CAPPARγ fusion protein mimicked the liganded PPARγ receptor and the transgenic mice displayed increased ectopic thymic adipogenesis and reduced thymopoiesis. Furthermore, the reduction in thymopoiesis in CA-PPARγ mice was associated with higher bone marrow adiposity and lower hematopoietic stem cell progenitor pool. Consistent with lower thymic output, CAPPARγ transgenic mice had restricted T cell receptor (TCR) repertoire diversity. Collectively, our data suggest that activation of PPARγ accelerates thymic aging and thymus-specific PPARγ antagonist may forestall age-related decline in T cell diversity. PMID:20374200

Analysis of Expression Pattern and Genetic Deletion of Netrin5 in the Developing Mouse

PubMed Central

Garrett, Andrew M.; Jucius, Thomas J.; Sigaud, Liam P. R.; Tang, Fu-Lei; Xiong, Wen-Cheng; Ackerman, Susan L.; Burgess, Robert W.

2016-01-01

Boundary cap cells (BCC) are a transient, neural-crest-derived population found at the motor exit point (MEP) and dorsal root entry zone (DREZ) of the embryonic spinal cord. These cells contribute to the central/peripheral nervous system (CNS/PNS) boundary, and in their absence neurons and glia from the CNS migrate into the PNS. We found Netrin5 (Ntn5), a previously unstudied member of the netrin gene family, to be robustly expressed in BCC. We generated Ntn5 knockout mice and examined neurodevelopmental and BCC-related phenotypes. No abnormalities in cranial nerve guidance, dorsal root organization, or sensory projections were found. However, Ntn5 mutant embryos did have ectopic motor neurons (MNs) that migrated out of the ventral horn and into the motor roots. Previous studies have implicated semaphorin6A (Sema6A) in BCC signaling to plexinA2 (PlxnA2)/neuropilin2 (Nrp2) in MNs in restricting MN cell bodies to the ventral horn, particularly in the caudal spinal cord. In Ntn5 mutants, ectopic MNs are likely to be a different population, as more ectopias were found rostrally. Furthermore, ectopic MNs in Ntn5 mutants were not immunoreactive for NRP2. The netrin receptor deleted in colorectal cancer (DCC) is a potential receptor for NTN5 in MNs, as similar ectopic neurons were found in Dcc mutant mice, but not in mice deficient for other netrin receptors. Thus, Ntn5 is a novel netrin family member that is expressed in BCC, functioning to prevent MN migration out of the CNS. PMID:26858598

CtBP impedes JNK- and Upd/STAT-driven cell fate misspecifications in regenerating Drosophila imaginal discs

PubMed Central

Worley, Melanie I; Alexander, Larissa A

2018-01-01

Regeneration following tissue damage often necessitates a mechanism for cellular re-programming, so that surviving cells can give rise to all cell types originally found in the damaged tissue. This process, if unchecked, can also generate cell types that are inappropriate for a given location. We conducted a screen for genes that negatively regulate the frequency of notum-to-wing transformations following genetic ablation and regeneration of the wing pouch, from which we identified mutations in the transcriptional co-repressor C-terminal Binding Protein (CtBP). When CtBP function is reduced, ablation of the pouch can activate the JNK/AP-1 and JAK/STAT pathways in the notum to destabilize cell fates. Ectopic expression of Wingless and Dilp8 precede the formation of the ectopic pouch, which is subsequently generated by recruitment of both anterior and posterior cells near the compartment boundary. Thus, CtBP stabilizes cell fates following damage by opposing the destabilizing effects of the JNK/AP-1 and JAK/STAT pathways. PMID:29372681

Pregnancy Luteoma in Ectopic Pregnancy: A Case Report.

PubMed

Brar, Rupinder Kaur; Bharti, Jyotsna Naresh; Nigam, Jitendra Singh; Sehgal, Sahil; Singh, Hena Paul; Ojha, Pushpanjali

2017-01-01

Pregnancy luteoma is a rare non neoplastic condition of the ovary. It is usually asymptomatic and found incidentally during imaging in pregnancy or during cesarean section. Pregnancy luteoma can also occur after ectopic pregnancy. A 30 year old female presented to G.B. Pant Hospital, Andaman and Nicobar Islands institute of Medical Sciences, Port Blair in October 2015 with abdominal pain. After initial investigations, exploratory laporotomy was done for ruptured ectopic pregnancy. Enlarged ovary was removed along with the ruptured portion of fallopian tube. Histopathological examination revealed solid aggregates of large cells with abundant eosinophilic cytoplasm; diagnosis of pregnancy luteoma was given. It must be considered in the differential diagnosis of ovarian masses in pregnant females that early diagnosis of this entity may avoid unnecessary radical surgery.

Transforming Growth Factor-β Promotes Liver Tumorigenesis in Mice via Up-regulation of Snail.

PubMed

Moon, Hyuk; Ju, Hye-Lim; Chung, Sook In; Cho, Kyung Joo; Eun, Jung Woo; Nam, Suk Woo; Han, Kwang-Hyub; Calvisi, Diego F; Ro, Simon Weonsang

2017-11-01

Transforming growth factor beta (TGF-β) suppresses early stages of tumorigenesis, but also contributes to migration and metastasis of cancer cells. A large number of human tumors contain mutations that inactivate its receptors, or downstream proteins such as Smad transcription factors, indicating that the TGF-β signaling pathway prevents tumor growth. We investigated the effects of TGF-β inhibition on liver tumorigenesis in mice. C57BL/6 mice received hydrodynamic tail-vein injections of transposons encoding HRAS G12V and a short hairpin RNA (shRNA) to down-regulate p53, or those encoding HRAS G12V and MYC, or those encoding HRAS G12V and TAZ S89A , to induce liver tumor formation; mice were also given injections of transposons encoding SMAD7 or shRNA against SMAD2, SMAD3, SMAD4, or SNAI1 (Snail), with or without ectopic expression of Snail. Survival times were compared, and livers were weighted and examined for tumors. Liver tumor tissues were analyzed by quantitative reverse-transcription PCR, RNA sequencing, immunoblots, and immunohistochemistry. We analyzed gene expression levels in human hepatocellular carcinoma samples deposited in The Cancer Genome Atlas. A cell proliferation assay was performed using human liver cancer cell lines (HepG2 and Huh7) stably expressing Snail or shRNA against Snail. TGF-β inhibition via overexpression of SMAD7 (or knockdown of SMAD2, SMAD3, or SMAD4) consistently reduced formation and growth of liver tumors in mice that expressed activated RAS plus shRNA against p53, or in mice that expressed activated RAS and TAZ. TGF-β signaling activated transcription of the Snail gene in liver tumors induced by HRAS G12V and shRNA against p53, and by activated RAS and TAZ. Knockdown of Snail reduced liver tumor formation in both tumor models. Ectopic expression of Snail restored liver tumorigenesis suppressed by disruption of TGF-β signaling. In human hepatocellular carcinoma, Snail expression correlated with TGF-β activation. Ectopic expression of Snail increased cellular proliferation, whereas Snail knockdown led to reduced proliferation in human hepatocellular carcinoma cells. In analyses of transgenic mice, we found TGF-β signaling to be required for formation of liver tumors upon expression of activated RAS and shRNA down-regulating p53, and upon expression of activated RAS and TAZ. Snail is the TGF-β target that is required for hepatic tumorigenesis in these models. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

[The modification of electrophysiology affected by ectopic synapse in ON-retinal bipolar cells of RCS rats].

PubMed

Zhang, Chen-xing; Yin, Zheng-qin; Weng, Chuan-huang; Zeng, Yu-xiao

2011-03-01

To study the influence of the ectopic synapse for electrophysiological characteristics modification in ON retinal bipolar cells (ON-RBCs) of RCS rat. Immunofluorescence of the retinal frozen section was taken in P60 d, P90 d of RCS rat (RCS) and control rat (CTR) with the anti-mGluR6 and anti-Synaptophysin, Lucifer Yellow staining solo ON-RBCs was taken in all the group. The whole cell recording was performed in the retinal slice of P60 d, P90 d in RCS and CTR. The modification of the passive membrane properties and the outward currents properties in RCS-ON-RBCs, CTR-ON-RBCs and CTR-OFF-RBCs were observed. RCS-ON-RBCs stretched out the ectopic neurite in different direction and the activity of synapse could be detected around the ectopic neurite. From Pn60d, passive membrane properties of RCS-ON-RBCs kept immature, The RMP in RCS-ON-RBCs and CTR-ON-RBCs were (-61.8 ± 3.07), (-50.44 ± 1.36) mV and (-63.1 ± 2.59), (-48.37 ± 3.69) mV when P60 d and P90 d, there ware significantly higher than CTR group (t = 2.191, 2.435, 5.817, 6.912;P < 0.05). The IR in RCS-ON-RBCs and CTR-ON-RBCs were (323.3 ± 42.6), (337.6 ± 71.3) MΩ and (321.2 ± 58.6), (340.3 ± 62.8) MΩ when P60 d and P90 d, there ware significantly higher than CTR group (t = 3.561, 1.987, 5.211, 4.034; P < 0.05). Outward currents were recorded when giving hyper- and depolarized voltage steps. In retinal degeneration, the amplitude of outward currents in RCS-ON-RBCs is significantly different with CTR-ON-RBCs (t = 5.561, 6.341; P < 0.05) or CTR-OFF-RBCs (t = 5.357, 6.997; P < 0.05). The ectopic neurite from RCS-ON-RBCs has the possibility for translating the signal. In retinitis pigmentosa, the modification of electrophysiology characteristics in RCS-ON-RBCs was significantly different with CTR-ON-RBCs and CTR-OFF-RBCs. Influence with the ectopic neurite is the possible cause.

Epithelial-Stromal Interaction 1 (EPSTI1) Substitutes for Peritumoral Fibroblasts in the Tumor Microenvironment

PubMed Central

de Neergaard, Michala; Kim, Jiyoung; Villadsen, René; Fridriksdottir, Agla J.; Rank, Fritz; Timmermans-Wielenga, Vera; Langerød, Anita; Børresen-Dale, Anne-Lise; Petersen, Ole W.; Rønnov-Jessen, Lone

2010-01-01

Tumor cells can activate stroma, yet the implication of this activation in terms of reciprocal induction of gene expression in tumor cells is poorly understood. Epithelial Stromal Interaction 1 (EPSTI1) is an interferon response gene originally isolated from heterotypic recombinant cultures of human breast cancer cells and activated breast myofibroblasts. Here we describe the first immunolocalization of EPSTI1 in normal and cancerous breast tissue, and we provide evidence for a role of this molecule in the regulation of tumor cell properties and epithelial-mesenchymal transition. In general, no EPSTI1 staining was observed in normal breast epithelial cells from reduction mammoplasties (n = 25). However, in carcinomas, staining was positive in 22 of 40 biopsies and inversely correlated with the level of differentiation. To address the function of EPSTI1, we expressed EPSTI1 ectopically in one cell line and silenced endogenous EPSTI1 by RNA interference in another. Irrespective of the experimental approach, EPSTI1 expression led to an increase in tumorsphere formation—a property associated with breast stem/progenitor cells. Most remarkably, we show that EPSTI1, by conveying spread of tumor cells, can replace peritumoral activated fibroblasts in a tumor environment assay. These observations implicate EPSTI1 as a hitherto unappreciated regulator of tumor cell properties. PMID:20133812

MicroRNA-139-5p acts as a tumor suppressor by targeting ELTD1 and regulating cell cycle in glioblastoma multiforme

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

Dai, Shouping; Wang, Xianjun; Li, Xiao

MicroRNA-139-5p was identified to be significantly down-regulated in glioblastoma multiform (GBM) by miRNA array. In this report we aimed to clarify its biological function, molecular mechanisms and direct target gene in GBM. Twelve patients with GBM were analyzed for the expression of miR-139-5p by quantitative RT-PCR. miR-139-5p overexpression was established by transfecting miR-139-5p-mimic into U87MG and T98G cells, and its effects on cell proliferation were studied using MTT assay and colony formation assays. We concluded that ectopic expression of miR-139-5p in GBM cell lines significantly suppressed cell proliferation and inducing apoptosis. Bioinformatics coupled with luciferase and western blot assays alsomore » revealed that miR-139-5p suppresses glioma cell proliferation by targeting ELTD1 and regulating cell cycle. - Highlights: • miR-139-5p is downregulated in GBM. • miR-139-5p regulates cell proliferation through inducing apoptosis. • miR-139-5p regulates glioblastoma tumorigenesis by targeting 3′UTR of ELTD1. • miR-139-5p is involved in cell cycle regulation.« less

Ectopically hTERT expressing adult human mesenchymal stem cells are less radiosensitive than their telomerase negative counterpart

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

Serakinci, Nedime; Christensen, Rikke; Graakjaer, Jesper

2007-03-10

During the past several years increasing evidence indicating that the proliferation capacity of mammalian cells is highly radiosensitive, regardless of the species and the tissue of origin of the cells, has accumulated. It has also been shown that normal bone marrow cells of mice have a similar radiosensitivity to other mammalian cells so far tested. In this study, we investigated the genetic effects of ionizing radiation (2.5-15 Gy) on normal human mesenchymal stem cells and their telomerised counterpart hMSC-telo1. We evaluated overall genomic integrity, DNA damage/repair by applying a fluorescence-detected alkaline DNA unwinding assay together with Western blot analyses formore » phosphorylated H2AX and Q-FISH was applied for investigation of telomeric damage. Our results indicate that hMSC and TERT-immortalized hMSCs can cope with relatively high doses of {gamma}-rays and that overall DNA repair is similar in the two cell lines. The telomeres were extensively destroyed after irradiation in both cell types suggesting that telomere caps are especially sensitive to radiation. The TERT-immortalized hMSCs showed higher stability at telomeric regions than primary hMSCs indicating that cells with long telomeres and high telomerase activity have the advantage of re-establishing the telomeric caps.« less

Mobilizing Transit-Amplifying Cell-Derived Ectopic Progenitors Prevents Hair Loss from Chemotherapy or Radiation Therapy.

PubMed

Huang, Wen-Yen; Lai, Shih-Fan; Chiu, Hsien-Yi; Chang, Michael; Plikus, Maksim V; Chan, Chih-Chieh; Chen, You-Tzung; Tsao, Po-Nien; Yang, Tsung-Lin; Lee, Hsuan-Shu; Chi, Peter; Lin, Sung-Jan

2017-11-15

Genotoxicity-induced hair loss from chemotherapy and radiotherapy is often encountered in cancer treatment, and there is a lack of effective treatment. In growing hair follicles (HF), quiescent stem cells (SC) are maintained in the bulge region, and hair bulbs at the base contain rapidly dividing, yet genotoxicity-sensitive transit-amplifying cells (TAC) that maintain hair growth. How genotoxicity-induced HF injury is repaired remains unclear. We report here that HFs mobilize ectopic progenitors from distinct TAC compartments for regeneration in adaptation to the severity of dystrophy induced by ionizing radiation (IR). Specifically, after low-dose IR, keratin 5 + basal hair bulb progenitors, rather than bulge SCs, were quickly activated to replenish matrix cells and regenerated all concentric layers of HFs, demonstrating their plasticity. After high-dose IR, when both matrix and hair bulb cells were depleted, the surviving outer root sheath cells rapidly acquired an SC-like state and fueled HF regeneration. Their progeny then homed back to SC niche and supported new cycles of HF growth. We also revealed that IR induced HF dystrophy and hair loss and suppressed WNT signaling in a p53- and dose-dependent manner. Augmenting WNT signaling attenuated the suppressive effect of p53 and enhanced ectopic progenitor proliferation after genotoxic injury, thereby preventing both IR- and cyclophosphamide-induced alopecia. Hence, targeted activation of TAC-derived progenitor cells, rather than quiescent bulge SCs, for anagen HF repair can be a potential approach to prevent hair loss from chemotherapy and radiotherapy. Cancer Res; 77(22); 6083-96. ©2017 AACR . ©2017 American Association for Cancer Research.

Role of DNA methylation in miR-200c/141 cluster silencing in invasive breast cancer cells.

PubMed

Neves, Rui; Scheel, Christina; Weinhold, Sandra; Honisch, Ellen; Iwaniuk, Katharina M; Trompeter, Hans-Ingo; Niederacher, Dieter; Wernet, Peter; Santourlidis, Simeon; Uhrberg, Markus

2010-08-03

The miR-200c/141 cluster has recently been implicated in the epithelial to mesenchymal transition (EMT) process. The expression of these two miRNAs is inversely correlated with tumorigenicity and invasiveness in several human cancers. The role of these miRNAs in cancer progression is based in part on their capacity to target the EMT activators ZEB1 and ZEB2, two transcription factors, which in turn repress expression of E-cadherin. Little is known about the regulation of the mir200c/141 cluster, whose targeting has been proposed as a promising new therapy for the most aggressive tumors. We show that the miR-200c/141 cluster is repressed by DNA methylation of a CpG island located in the promoter region of these miRNAs. Whereas in vitro methylation of the miR-200c/141 promoter led to shutdown of promoter activity, treatment with a demethylating agent caused transcriptional reactivation in breast cancer cells formerly lacking expression of miR-200c and miR-141. More importantly, we observed that DNA methylation of the identified miR-200c/141 promoter was tightly correlated with phenotype and the invasive capacity in a panel of 8 human breast cancer cell lines. In line with this, in vitro induction of EMT by ectopic expression of the EMT transcription factor Twist in human immortalized mammary epithelial cells (HMLE) was accompanied by increased DNA methylation and concomitant repression of the miR-200c/141 locus. The present study demonstrates that expression of the miR-200c/141 cluster is regulated by DNA methylation, suggesting epigenetic regulation of this miRNA locus in aggressive breast cancer cell lines as well as untransformed mammary epithelial cells. This epigenetic silencing mechanism might represent a novel component of the regulatory circuit for the maintenance of EMT programs in cancer and normal cells.

MicroRNA-34a targets epithelial to mesenchymal transition-inducing transcription factors (EMT-TFs) and inhibits breast cancer cell migration and invasion

PubMed Central

Fu, Shangyi; Yang, Luquan; Tania, Mousumi; Zhang, Xianqin; Xiao, Xiuli; Zhang, Xianning; Fu, Junjiang

2017-01-01

MicroRNA-34a (miR-34a) plays an essential role against tumorigenesis and progression of cancer metastasis. Here, we analyzed the expression, targets and functional effects of miR-34a on epithelial to mesenchymal transition-inducing transcription factors (EMT-TFs), such as TWIST1, SLUG and ZEB1/2, and an EMT-inducing protein NOTCH1 in breast cancer (BC) cell migration and invasion and its correlation with tumorigenesis and clinical outcomes. Expression of miR-34a is downregulated in human metastatic breast cancers (MBC) compared to normal breast tissues and is negatively correlated with clinicopathological features of MBC patients. Ectopic expression of miR-34a in MBC cell-line BT-549 significantly inhibits cell migration and invasion, but exhibits no clear effect on BC cell growth. We found that miR-34a is able to inactivate EMT signaling pathway with mediatory of NOTCH1, TWIST1, and ZEB1 upon 3′-UTR activity in MBC cell lines, but has no inhibitory effects on SLUG and ZEB2. Furthermore, we investigated the synergistic effects of Thymoquinone (TQ) and miR-34a together on the expression of EMT-associated proteins. Results showed that co-delivery of miR-34a and TQ is able to inactivate EMT signaling pathway by directly targeting TWIST1 and ZEB1 in BT-549 cell line, indicating that they might be a promising therapeutic combination against breast cancer metastasis. Epigenetic inactivation of the EMT-TFs/miR-34a pathway can potentially alter the equilibrium of these regulations, facilitating EMT and metastasis in BC. Altogether, our findings suggest that miR-34a alone could serve as a potential therapeutic agent for MBC, and together with TQ, their therapeutic potential is synergistically enhanced. PMID:28423483

MicroRNA-34a targets epithelial to mesenchymal transition-inducing transcription factors (EMT-TFs) and inhibits breast cancer cell migration and invasion.

PubMed

Imani, Saber; Wei, Chunli; Cheng, Jingliang; Khan, Md Asaduzzaman; Fu, Shangyi; Yang, Luquan; Tania, Mousumi; Zhang, Xianqin; Xiao, Xiuli; Zhang, Xianning; Fu, Junjiang

2017-03-28

MicroRNA-34a (miR-34a) plays an essential role against tumorigenesis and progression of cancer metastasis. Here, we analyzed the expression, targets and functional effects of miR-34a on epithelial to mesenchymal transition-inducing transcription factors (EMT-TFs), such as TWIST1, SLUG and ZEB1/2, and an EMT-inducing protein NOTCH1 in breast cancer (BC) cell migration and invasion and its correlation with tumorigenesis and clinical outcomes. Expression of miR-34a is downregulated in human metastatic breast cancers (MBC) compared to normal breast tissues and is negatively correlated with clinicopathological features of MBC patients. Ectopic expression of miR-34a in MBC cell-line BT-549 significantly inhibits cell migration and invasion, but exhibits no clear effect on BC cell growth. We found that miR-34a is able to inactivate EMT signaling pathway with mediatory of NOTCH1, TWIST1, and ZEB1 upon 3'-UTR activity in MBC cell lines, but has no inhibitory effects on SLUG and ZEB2. Furthermore, we investigated the synergistic effects of Thymoquinone (TQ) and miR-34a together on the expression of EMT-associated proteins. Results showed that co-delivery of miR-34a and TQ is able to inactivate EMT signaling pathway by directly targeting TWIST1 and ZEB1 in BT-549 cell line, indicating that they might be a promising therapeutic combination against breast cancer metastasis. Epigenetic inactivation of the EMT-TFs/miR-34a pathway can potentially alter the equilibrium of these regulations, facilitating EMT and metastasis in BC. Altogether, our findings suggest that miR-34a alone could serve as a potential therapeutic agent for MBC, and together with TQ, their therapeutic potential is synergistically enhanced.

Long non-coding RNA LSINCT5 predicts negative prognosis and exhibits oncogenic activity in gastric cancer.

PubMed

Xu, Mi-Die; Qi, Peng; Weng, Wei-Wei; Shen, Xiao-Han; Ni, Shu-Juan; Dong, Lei; Huang, Dan; Tan, Cong; Sheng, Wei-Qi; Zhou, Xiao-Yan; Du, Xiang

2014-12-01

Long non-coding RNAs (lncRNAs) are recently discovered RNA transcripts that are aberrantly expressed in many tumor types. Numerous studies have suggested that lncRNAs can be utilized for cancer diagnosis and prognosis. LSINCT5 (long stress-induced non-coding transcript 5) is dramatically upregulated in breast and ovarian cancer and affects cellular proliferation. However, the expression pattern of LSINCT5 in gastrointestinal cancer and the association between aberrant expression of LSINCT5 in gastrointestinal cancer and malignancy, metastasis, or prognosis remain unknown. LSINCT5 expression was detected in gastrointestinal cancer and paired adjacent normal tissue samples or cell lines using reverse transcription quantitative PCR (RT-qPCR). We also investigated the potential relationship between tumor LSINCT5 levels and clinicopathological features of gastrointestinal cancer. Finally, we assessed whether LSINCT5 influences in vitro cell proliferation. The expression of LSINCT5 is significantly upregulated in gastrointestinal cancer tissues and cell lines relative to their normal counterparts. In addition, increased LSINCT5 expression was correlated with a larger tumor size, deeper tumor depth, and advanced clinical stage. Kaplan-Meier analysis indicated that gastric cancer (GC) and colorectal cancer (CRC) patients with higher LSINCT5 expression levels have worse disease-free survival (DFS) and disease-specific survival (DSS) rates. Moreover, multivariate analysis revealed that increased expression of LSINCT5 is an independent predictor of DFS and DSS rates in GC patients. The ectopic expression of LSINCT5 in gastrointestinal cancer cell lines resulted in an increase in cellular proliferation; conversely, knock down of LSINCT5 significantly inhibited proliferation. These results suggest that LSINCT5 may represent a novel prognostic indicator and a target for gene therapy in gastrointestinal cancer.

The candidate tumor suppressor gene BLU, located at the commonly deleted region 3p21.3, is an E2F-regulated, stress-responsive gene and inactivated by both epigenetic and genetic mechanisms in nasopharyngeal carcinoma.

PubMed

Qiu, Guo-Hua; Tan, Luke K S; Loh, Kwok Seng; Lim, Chai Yen; Srivastava, Gopesh; Tsai, Sen-Tien; Tsao, Sai Wah; Tao, Qian

2004-06-10

Loss of heterozygosity at 3p21 is common in various cancers including nasopharyngeal carcinoma (NPC). BLU is one of the candidate tumor suppressor genes (TSGs) in this region. Ectopic expression of BLU results in the inhibition of colony formation of cancer cells, suggesting that BLU is a tumor suppressor. We have identified a functional BLU promoter and found that it can be activated by environmental stresses such as heat shock, and is regulated by E2F. The promoter and first exon are located within a CpG island. BLU is highly expressed in testis and normal upper respiratory tract tissues including nasopharynx. However, in all seven NPC cell lines examined, BLU expression was downregulated and inversely correlated with promoter hypermethylation. Biallelic epigenetic inactivation of BLU was also observed in three cell lines. Hypermethylation was further detected in 19/29 (66%) of primary NPC tumors, but not in normal nasopharyngeal tissues. Treatment of NPC cell lines with 5-aza-2'-deoxycytidine activated BLU expression along with promoter demethylation. Although hypermethylation of RASSF1A, another TSG located immediately downstream of BLU, was detected in 20/27 (74%) of NPC tumors, no correlation between the hypermethylation of these two TSGs was observed (P=0.6334). In addition to methylation, homozygous deletion of BLU was found in 7/29 (24%) of tumors. Therefore, BLU is a stress-responsive gene, being disrupted in 83% (24/29) of NPC tumors by either epigenetic or genetic mechanisms. Our data are consistent with the interpretation that BLU is a TSG for NPC.

TRIM25 blockade by RNA interference inhibited migration and invasion of gastric cancer cells through TGF-β signaling.

PubMed

Zhu, Zhenya; Wang, Yong; Zhang, Chunhui; Yu, Shiyong; Zhu, Qi; Hou, Kun; Yan, Bo

2016-01-12

Tripartite Motif Containing 25 (TRIM25), a member of TRIM proteins, has been found abnormally expressed in cancers of female reproductive system. Here, TRIM25 was conspicuously expressed in human gastric cancer (GC) tissues in which its higher expression generally correlated with the poor prognosis of patients. Small interfering RNA (siRNA)-mediated knockdown of TRIM25 expression in MGC-803 and AGS cells had no effects on cell proliferation, whereas reduced cell migration and invasion. Gene set enrichment analysis on The Cancer Genome Atlas stomach adenocarcinoma (STAD) dataset revealed that several signaling pathways, including the migration, E-cadherin and transforming growth factor-β (TGF-β) pathways, were enriched in TRIM25 higher expression patients. Moreover, ectopic expression of TRIM25 in a GC cell line with lower expression of TRIM25 significantly promoted the migration and invasion. Further experiments with TGF-β inhibitor suggested that TRIM25 may exert its function through TGF-β pathway. In summary, our results indicate that TRIM25 acts as an oncogene in GC and thus presents a novel target for the detection and treatment of GC.

TRIM25 blockade by RNA interference inhibited migration and invasion of gastric cancer cells through TGF-β signaling

PubMed Central

Zhu, Zhenya; Wang, Yong; Zhang, Chunhui; Yu, Shiyong; Zhu, Qi; Hou, Kun; Yan, Bo

2016-01-01

Tripartite Motif Containing 25 (TRIM25), a member of TRIM proteins, has been found abnormally expressed in cancers of female reproductive system. Here, TRIM25 was conspicuously expressed in human gastric cancer (GC) tissues in which its higher expression generally correlated with the poor prognosis of patients. Small interfering RNA (siRNA)-mediated knockdown of TRIM25 expression in MGC-803 and AGS cells had no effects on cell proliferation, whereas reduced cell migration and invasion. Gene set enrichment analysis on The Cancer Genome Atlas stomach adenocarcinoma (STAD) dataset revealed that several signaling pathways, including the migration, E-cadherin and transforming growth factor-β (TGF-β) pathways, were enriched in TRIM25 higher expression patients. Moreover, ectopic expression of TRIM25 in a GC cell line with lower expression of TRIM25 significantly promoted the migration and invasion. Further experiments with TGF-β inhibitor suggested that TRIM25 may exert its function through TGF-β pathway. In summary, our results indicate that TRIM25 acts as an oncogene in GC and thus presents a novel target for the detection and treatment of GC. PMID:26754079

SUPPRESSION OF THE EPITHELIAL-MESENCHYMAL TRANSITION BY GRAINYHEAD-LIKE-2

PubMed Central

Cieply, Benjamin; Riley, Philip; Pifer, Phillip M.; Widmeyer, Joseph; Addison, Joseph B.; Ivanov, Alexey V.; Denvir, James; Frisch, Steven M.

2012-01-01

Grainyhead genes are involved in wound healing and developmental neural tube closure. In light of the high degree of similarity between the epithelial-mesenchymal transitions (EMT) occurring in wound healing processes and the cancer stem cell-like compartment of tumors, including TGF-β-dependence, we investigated the role of the Grainyhead gene, Grainyhead-Like-2 (GRHL2) in oncogenic EMT. GRHL2 was down-regulated specifically in the claudin-low subclass breast tumors and in basal-B subclass breast cancer cell lines. GRHL2 suppressed TGF-β-induced, Twist-induced or spontaneous EMT, enhanced anoikis-sensitivity, and suppressed mammosphere generation in mammary epithelial cells. These effects were mediated in part by suppression of ZEB1 expression via direct repression of the ZEB1 promoter. GRHL2 also inhibited Smad-mediated transcription and it upregulated mir200b/c as well as the TGF-β receptor antagonist, BMP2. Lastly, ectopic expression of GRHL2 in MDA-MB-231 breast cancer cells triggered a mesenchymal-to-epithelial transition and restored sensitivity to anoikis. Taken together, our findings define a major role for GRHL2 in the suppression of oncogenic EMT in breast cancer cells. PMID:22379025

Loss of anchorage primarily induces non-apoptotic cell death in a human mammary epithelial cell line under atypical focal adhesion kinase signaling.

PubMed

Ishikawa, F; Ushida, K; Mori, K; Shibanuma, M

2015-01-22

Anchorage dependence of cellular growth and survival prevents inappropriate cell growth or survival in ectopic environments, and serves as a potential barrier to metastasis of cancer cells. Therefore, obtaining a better understanding of anchorage-dependent responses in normal cells is the first step to understand and impede anchorage independence of growth and survival in cancer cells and finally to eradicate cancer cells during metastasis. Anoikis, a type of apoptosis specifically induced by lack of appropriate cell-extracellular matrix adhesion, has been established as the dominant response of normal epithelial cells to anchorage loss. For example, under detached conditions, the untransformed mammary epithelial cell (MEC) line MCF-10 A, which exhibits myoepithelial characteristics, underwent anoikis dependent on classical ERK signaling. On the other hand, recent studies have revealed a variety of phenotypes resulting in cell death modalities distinct from anoikis, such as autophagy, necrosis, and cornification, in detached epithelial cells. In the present study, we characterized detachment-induced cell death (DICD) in primary human MECs immortalized with hTERT ((Tert)HMECs), which are bipotent progenitor-like cells with a differentiating phenotype to luminal cells. In contrast to MCF-10 A cells, apoptosis was not observed in detached (Tert)HMECs; instead, non-apoptotic cell death marked by features of entosis, cornification, and necrosis was observed along with downregulation of focal adhesion kinase (FAK) signaling. Cell death was overcome by anchorage-independent activities of FAK but not PI3K/AKT, SRC, and MEK/ERK, suggesting critical roles of atypical FAK signaling pathways in the regulation of non-apoptotic cell death. Further analysis revealed an important role of TRAIL (tumor necrosis factor (TNF)-related apoptosis-inducing ligand) as a mediator of FAK signaling in regulation of entosis and necrosis and a role of p38 MAPK in the induction of necrosis. Overall, the present study highlighted outstanding cell subtype or differentiation stage specificity in cell death phenotypes induced upon anchorage loss in human MECs.

Acute myelobalstic leukemia and hypercalcemia. A case of probable ectopic parathyroid hormone production.

PubMed

Zidar, B L; Shadduck, R K; Winkelstein, A; Zeigler, Z; Hawker, C D

1976-09-23

We studied a patient with acute myeloblastic leukemia, hypercalcemia, hypophosphatemia and inappropriately elevated serum parathyroid hormone levels to define the mechanism of the hypercalcemia. On six occasions during two years, hypercalcemia occurred in conjunction with relapses of leukmia. Each time, serum calcium decreased to normal levels in parallel with reduction of the leukemic mass. During two periods of hypercalcemia, immunoreactive parathyroid hormone values were abnormally high. In addition, hormone was detected in vitro after short-term incubation of the leukemic cells (after 24 hours, the patient's cells produced 129 pg of PTH per milliliter, whereas myeloblasts from a normocalcemic patient with leukemia produced only 33 pg). In freeze-thawing experiments, 39 pg of parathyroid hormone was released form 1 x 108 of the patient's myeloblasts; no hormone was released from the normocalcemia cells. These findings suggest that the hypercalcemia resulted from ectopic parathyroid hormone production by leukemic cells.

Expression and phosphorylation of the AS160_v2 splice variant supports GLUT4 activation and the Warburg effect in multiple myeloma

PubMed Central

2013-01-01

Background Multiple myeloma (MM) is a fatal plasma cell malignancy exhibiting enhanced glucose consumption associated with an aerobic glycolytic phenotype (i.e., the Warburg effect). We have previously demonstrated that myeloma cells exhibit constitutive plasma membrane (PM) localization of GLUT4, consistent with the dependence of MM cells on this transporter for maintenance of glucose consumption rates, proliferative capacity, and viability. The purpose of this study was to investigate the molecular basis of constitutive GLUT4 plasma membrane localization in MM cells. Findings We have elucidated a novel mechanism through which myeloma cells achieve constitutive GLUT4 activation involving elevated expression of the Rab-GTPase activating protein AS160_v2 splice variant to promote the Warburg effect. AS160_v2-positive MM cell lines display constitutive Thr642 phosphorylation, known to be required for inactivation of AS160 Rab-GAP activity. Importantly, we show that enforced expression of AS160_v2 is required for GLUT4 PM translocation and activation in these select MM lines. Furthermore, we demonstrate that ectopic expression of a full-length, phospho-deficient AS160 mutant is sufficient to impair constitutive GLUT4 cell surface residence, which is characteristic of MM cells. Conclusions This is the first study to tie AS160 de-regulation to increased glucose consumption rates and the Warburg effect in cancer. Future studies investigating connections between the insulin/IGF-1/AS160_v2/GLUT4 axis and FDG-PET positivity in myeloma patients are warranted and could provide rationale for therapeutically targeting this pathway in MM patients with advanced disease. PMID:24280290

The Homeodomain Transcription Factor Cdx1 Does Not Behave as an Oncogene in Normal Mouse Intestine1

PubMed Central

Crissey, Mary Ann S; Guo, Rong-Jun; Fogt, Franz; Li, Hong; Katz, Jonathan P; Silberg, Debra G; Suh, Eun Ran; Lynch, John P

2008-01-01

The Caudal-related homeobox genes Cdx1 and Cdx2 are intestine-specific transcription factors that regulate differentiation of intestinal cell types. Previously, we have shown Cdx1 to be antiproliferative and to promote cell differentiation. However, other studies have suggested that Cdx1 may be an oncogene. To test for oncogenic behavior, we used the murine villin promoter to ectopically express Cdx1 in the small intestinal villi and colonic surface epithelium. No changes in intestinal architecture, cell differentiation, or lineage selection were observed with expression of the transgene. Classic oncogenes enhance proliferation and induce tumors when ectopically expressed. However, the Cdx1 transgene neither altered intestinal proliferation nor induced spontaneous intestinal tumors. In a murine model for colitis-associated cancer, the Cdx1 transgene decreased, rather than increased, the number of adenomas that developed. In the polyps, the expression of the endogenous and the transgenic Cdx1 proteins was largely absent, whereas endogenous Villin expression was retained. This suggests that transgene silencing was specific and not due to a general Villin inactivation. In conclusion, neither the ectopic expression of Cdx1 was associated with changes in intestinal cell proliferation or differentiation nor was there increased intestinal cancer susceptibility. Our results therefore suggest that Cdx1 is not an oncogene in normal intestinal epithelium. PMID:18231635

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

Srisuttee, Ratakorn; Koh, Sang Seok; Department of Functional Genomics, University of Science and Technology, Daejeon 305-333

Highlights: Black-Right-Pointing-Pointer Up-regulation of SIRT1 protein and activity sensitizes Hep3B-HBX cells to oxidative stress-induced apoptosis. Black-Right-Pointing-Pointer Nuclear localization of SIRT1 is not required for oxidation-induced apoptosis. Black-Right-Pointing-Pointer Ectopic expression and enhanced activity of SIRT1 attenuate JNK phosphorylation. Black-Right-Pointing-Pointer Inhibition of SIRT1 activity restores resistance to oxidation-induced apoptosis through JNK activation. -- Abstract: We previously showed that SIRT1 deacetylase inhibits proliferation of hepatocellular carcinoma cells expressing hepatitis B virus (HBV) X protein (HBX), by destabilization of {beta}-catenin. Here, we report another role for SIRT1 in HBX-mediated resistance to oxidative stress. Ectopic expression and enhanced activity of SIRT1 sensitize Hep3B cells stablymore » expressing HBX to oxidative stress-induced apoptosis. SIRT1 mutant analysis showed that nuclear localization of SIRT1 is not required for sensitization of oxidation-mediated apoptosis. Furthermore, ectopic expression of SIRT1 and treatment with resveratrol (a SIRT1 activator) attenuated JNK phosphorylation, which is a prerequisite for resistance to oxidative stress-induced apoptosis. Conversely, suppression of SIRT1 activity with nicotinamide inhibited the effect of resveratrol on JNK phosphorylation, leading to restoration of resistance to oxidation-induced apoptosis. Taken together, these results suggest that up-regulation of SIRT1 under oxidative stress may be a therapeutic strategy for treatment of hepatocellular carcinoma cells related to HBV through inhibition of JNK activation.« less

HCN4-Overexpressing Mouse Embryonic Stem Cell-Derived Cardiomyocytes Generate a New Rapid Rhythm in Rats with Bradycardia.

PubMed

Saito, Yukihiro; Nakamura, Kazufumi; Yoshida, Masashi; Sugiyama, Hiroki; Takano, Makoto; Nagase, Satoshi; Morita, Hiroshi; Kusano, Kengo F; Ito, Hiroshi

2018-05-30

A biological pacemaker is expected to solve the persisting problems of an artificial cardiac pacemaker including short battery life, lead breaks, infection, and electromagnetic interference. We previously reported HCN4 overexpression enhances pacemaking ability of mouse embryonic stem cell-derived cardiomyocytes (mESC-CMs) in vitro. However, the effect of these cells on bradycardia in vivo has remained unclear. Therefore, we transplanted HCN4-overexpressing mESC-CMs into bradycardia model animals and investigated whether they could function as a biological pacemaker. The rabbit Hcn4 gene was transfected into mouse embryonic stem cells and induced HCN4-overexpressing mESC-CMs. Non-cardiomyocytes were removed under serum/glucose-free and lactate-supplemented conditions. Cardiac balls containing 5 × 10 3 mESC-CMs were made by using the hanging drop method. One hundred cardiac balls were injected into the left ventricular free wall of complete atrioventricular block (CAVB) model rats. Heart beats were evaluated using an implantable telemetry system 7 to 30 days after cell transplantation. The result showed that ectopic ventricular beats that were faster than the intrinsic escape rhythm were often observed in CAVB model rats transplanted with HCN4-overexpressing mESC-CMs. On the other hand, the rats transplanted with non-overexpressing mESC-CMs showed sporadic single premature ventricular contraction but not sustained ectopic ventricular rhythms. These results indicated that HCN4-overexpressing mESC-CMs produce rapid ectopic ventricular rhythms as a biological pacemaker.

Osteogenic differentiation capacity of human skeletal muscle-derived progenitor cells.

PubMed

Oishi, Teruyo; Uezumi, Akiyoshi; Kanaji, Arihiko; Yamamoto, Naoki; Yamaguchi, Asami; Yamada, Harumoto; Tsuchida, Kunihiro

2013-01-01

Heterotopic ossification (HO) is defined as the formation of ectopic bone in soft tissue outside the skeletal tissue. HO is thought to result from aberrant differentiation of osteogenic progenitors within skeletal muscle. However, the precise origin of HO is still unclear. Skeletal muscle contains two kinds of progenitor cells, myogenic progenitors and mesenchymal progenitors. Myogenic and mesenchymal progenitors in human skeletal muscle can be identified as CD56(+) and PDGFRα(+) cells, respectively. The purpose of this study was to investigate the osteogenic differentiation potential of human skeletal muscle-derived progenitors. Both CD56(+) cells and PDGFRα(+) cells showed comparable osteogenic differentiation potential in vitro. However, in an in vivo ectopic bone formation model, PDGFRα(+) cells formed bone-like tissue and showed successful engraftment, while CD56(+) cells did not form bone-like tissue and did not adapt to an osteogenic environment. Immunohistological analysis of human HO sample revealed that many PDGFRα(+) cells were localized in proximity to ectopic bone formed in skeletal muscle. MicroRNAs (miRNAs) are known to regulate many biological processes including osteogenic differentiation. We investigated the participation of miRNAs in the osteogenic differentiation of PDGFRα(+) cells by using microarray. We identified miRNAs that had not been known to be involved in osteogenesis but showed dramatic changes during osteogenic differentiation of PDGFRα(+) cells. Upregulation of miR-146b-5p and -424 and downregulation of miR-7 during osteogenic differentiation of PDGFRα(+) cells were confirmed by quantitative real-time RT-PCR. Inhibition of upregulated miRNAs, miR-146b-5p and -424, resulted in the suppression of osteocyte maturation, suggesting that these two miRNAs have the positive role in the osteogenesis of PDGFRα(+) cells. Our results suggest that PDGFRα(+) cells may be the major source of HO and that the newly identified miRNAs may regulate osteogenic differentiation process of PDGFRα(+) cells.

A rare case of an ACTH/CRH co-secreting midgut neuroendocrine tumor mimicking Cushing's disease

PubMed Central

Streuli, Regina; Krull, Ina; Brändle, Michael; Kolb, Walter; Stalla, Günter; Theodoropoulou, Marily; Enzler-Tschudy, Annette

2017-01-01

Ectopic ACTH/CRH co-secreting tumors are a very rare cause of Cushing’s syndrome and only a few cases have been reported in the literature. Differentiating between Cushing’s disease and ectopic Cushing’s syndrome may be particularly difficult if predominant ectopic CRH secretion leads to pituitary corticotroph hyperplasia that may mimic Cushing’s disease during dynamic testing with both dexamethasone and CRH as well as bilateral inferior petrosal sinus sampling (BIPSS). We present the case of a 24-year-old man diagnosed with ACTH-dependent Cushing’s syndrome caused by an ACTH/CRH co-secreting midgut NET. Both high-dose dexamethasone testing and BIPSS suggested Cushing’s disease. However, the clinical presentation with a rather rapid onset of cushingoid features, hyperpigmentation and hypokalemia led to the consideration of ectopic ACTH/CRH-secretion and prompted a further workup. Computed tomography (CT) of the abdomen revealed a cecal mass which was identified as a predominantly CRH-secreting neuroendocrine tumor. To the best of our knowledge, this is the first reported case of an ACTH/CRH co-secreting tumor of the cecum presenting with biochemical features suggestive of Cushing’s disease. Learning points: The discrimination between a Cushing’s disease and ectopic Cushing’s syndrome is challenging and has many caveats. Ectopic ACTH/CRH co-secreting tumors are very rare. Dynamic tests as well as BIPSS may be compatible with Cushing’s disease in ectopic CRH-secretion. High levels of CRH may induce hyperplasia of the corticotroph cells in the pituitary. This could be the cause of a preserved pituitary response to dexamethasone and CRH. Clinical features of ACTH-dependent hypercortisolism with rapid development of Cushing’s syndrome, hyperpigmentation, high circulating levels of cortisol with associated hypokalemia, peripheral edema and proximal myopathy should be a warning flag of ectopic Cushing’s syndrome and lead to further investigations. PMID:28680643

Loss of the Nuclear Pool of Ubiquitin Ligase CHIP/STUB1 in Breast Cancer Unleashes the MZF1-Cathepsin Pro-oncogenic Program.

PubMed

Luan, Haitao; Mohapatra, Bhopal; Bielecki, Timothy A; Mushtaq, Insha; Mirza, Sameer; Jennings, Tameka A; Clubb, Robert J; An, Wei; Ahmed, Dena; El-Ansari, Rokaya; Storck, Matthew D; Mishra, Nitish K; Guda, Chittibabu; Sheinin, Yuri M; Meza, Jane L; Raja, Srikumar; Rakha, Emad A; Band, Vimla; Band, Hamid

2018-05-15

CHIP/STUB1 ubiquitin ligase is a negative co-chaperone for HSP90/HSC70, and its expression is reduced or lost in several cancers, including breast cancer. Using an extensive and well-annotated breast cancer tissue collection, we identified the loss of nuclear but not cytoplasmic CHIP to predict more aggressive tumorigenesis and shorter patient survival, with loss of CHIP in two thirds of ErbB2 + and triple-negative breast cancers (TNBC) and in one third of ER + breast cancers. Reduced CHIP expression was seen in breast cancer patient-derived xenograft tumors and in ErbB2 + and TNBC cell lines. Ectopic CHIP expression in ErbB2 + lines suppressed in vitro oncogenic traits and in vivo xenograft tumor growth. An unbiased screen for CHIP-regulated nuclear transcription factors identified many candidates whose DNA-binding activity was up- or downregulated by CHIP. We characterized myeloid zinc finger 1 (MZF1) as a CHIP target, given its recently identified role as a positive regulator of cathepsin B/L (CTSB/L)-mediated tumor cell invasion downstream of ErbB2. We show that CHIP negatively regulates CTSB/L expression in ErbB2 + and other breast cancer cell lines. CTSB inhibition abrogates invasion and matrix degradation in vitro and halts ErbB2 + breast cancer cell line xenograft growth. We conclude that loss of CHIP remodels the cellular transcriptome to unleash critical pro-oncogenic pathways, such as the matrix-degrading enzymes of the cathepsin family, whose components can provide new therapeutic opportunities in breast and other cancers with loss of CHIP expression. Significance: These findings reveal a novel targetable pathway of breast oncogenesis unleashed by the loss of tumor suppressor ubiquitin ligase CHIP/STUB1. Cancer Res; 78(10); 2524-35. ©2018 AACR . ©2018 American Association for Cancer Research.

Regulation of planar growth by the Arabidopsis AGC protein kinase UNICORN.

PubMed

Enugutti, Balaji; Kirchhelle, Charlotte; Oelschner, Maxi; Torres Ruiz, Ramón Angel; Schliebner, Ivo; Leister, Dario; Schneitz, Kay

2012-09-11

The spatial coordination of growth is of central importance for the regulation of plant tissue architecture. Individual layers, such as the epidermis, are clonally propagated and structurally maintained by symmetric cell divisions that are oriented along the plane of the layer. The developmental control of this process is poorly understood. The simple cellular basis and sheet-like structure of Arabidopsis integuments make them an attractive model system to address planar growth. Here we report on the characterization of the Arabidopsis UNICORN (UCN) gene. Analysis of ucn integuments reveals localized distortion of planar growth, eventually resulting in an ectopic multicellular protrusion. In addition, ucn mutants exhibit ectopic growth in filaments and petals, as well as aberrant embryogenesis. We further show that UCN encodes an active AGC VIII kinase. Genetic, biochemical, and cell biological data suggest that UCN suppresses ectopic growth in integuments by directly repressing the KANADI transcription factor ABERRANT TESTA SHAPE. Our findings indicate that UCN represents a unique plant growth regulator that maintains planar growth of integuments by repressing a developmental regulator involved in the control of early integument growth and polarity.

Ectopic hyperprolactinaemia in a woman with a mesocolic perivascular epithelioid cell tumor ("PEComa").

PubMed

Proust-Lemoine, E; Mitchell, V; Deruelle, P; Lamblin, A; Néraud, B; Leroy, X; Leteurtre, E; Dewailly, D

2008-06-01

Ectopic prolactin secretion remains exceptional and originates mainly from malignant tumors. We report the case of a 47-year-old woman who presented amenorrhea leading to unravel important hyperprolactinaemia (269 ng/mL) with no hypothalamo-pituitary mass on magnetic resonance imaging (MRI). Pelvic imaging revealed the presence of a large pelvic mass that originated from the mesocolon. After complete surgical extraction, histological examination was in favour of a "perivascular epithelioid cell tumor" (PEComa). Prolactin levels normalized after surgical extraction and remained normal after a 3-year follow-up, totally free of tumour recurrence and/or metastasis. This suggests that hyperprolactinaemia was most likely related to the PEComa, despite negative reactions with antiprolactin antibodies at immunohistochemistry. Alternatively to a direct prolactin secretion by the tumor, one could hypothesize that the tumour secreted a prolactin stimulating factor or a dopamine antagonist that could not be identified. In conclusion, in face of an important hyperprolactinaemia without any hypothalamic-pituitary mass, it remains important to search for an ectopic prolactin production, such as a PEComa.

Abnormal development of floral meristem triggers defective morphogenesis of generative system in transgenic tomatoes.

PubMed

Chaban, Inna; Khaliluev, Marat; Baranova, Ekaterina; Kononenko, Neonila; Dolgov, Sergey; Smirnova, Elena

2018-04-21

Parthenocarpy and fruit malformations are common among independent transgenic tomato lines, expressing genes encoding different pathogenesis-related (PR) protein and antimicrobal peptides. Abnormal phenotype developed independently of the expression and type of target genes, but distinctive features during flower and fruit development were detected in each transgenic line. We analyzed the morphology, anatomy, and cytoembryology of abnormal flowers and fruits from these transgenic tomato lines and compared them with flowers and fruits of wild tomatoes, line YaLF used for transformation, and transgenic plants with normal phenotype. We confirmed that the main cause of abnormal flower and fruit development was the alterations of determinate growth of generative meristem. These alterations triggered different types of anomalous growth, affecting the number of growing ectopic shoots and formation of new flowers. Investigation of the ovule ontogenesis did not show anomalies in embryo sac development, but fertilization did not occur and embryo sac degenerated. Nevertheless, the ovule continued to differentiate due to proliferation of endothelium cells. The latter substituted embryo sac and formed pseudoembryonic tissue. This process imitated embryogenesis and stimulated ovary growth, leading to the development of parthenocarpic fruit. We demonstrated that failed fertilization occurred due to defective male gametophyte formation, which was manifested in blocked division of the nucleus in the microspore and arrest of vegetative and generative cell formation. Maturing pollen grains were overgrown microspores, not competent for fertilization but capable to induce proliferation of endothelium and development of parthenocarpic ovary. Thus, our study provided new data on the structural transformations of reproductive organs during development of parthenocarpic fruits in transgenic tomato.

The ginsenoside PPD exerts anti-endometriosis effects by suppressing estrogen receptor-mediated inhibition of endometrial stromal cell autophagy and NK cell cytotoxicity.

PubMed

Zhang, Bing; Zhou, Wen-Jie; Gu, Chun-Jie; Wu, Ke; Yang, Hui-Li; Mei, Jie; Yu, Jia-Jun; Hou, Xiao-Fan; Sun, Jian-Song; Xu, Feng-Yuan; Li, Da-Jin; Jin, Li-Ping; Li, Ming-Qing

2018-05-14

Endometriosis (EMS) is an estrogen-dependent gynecological disease with a low autophagy level of ectopic endometrial stromal cells (eESCs). Impaired NK cell cytotoxic activity is involved in the clearance obstruction of the ectopic endometrial tissue in the abdominopelvic cavity. Protopanaxadiol (PPD) and protopanaxatriol (PPT) are two metabolites of ginsenosides, which have profound biological functions, such as anti-cancer activities. However, the role and mechanism of ginsenosides and metabolites in endometriosis are completely unknown. Here, we found that the compounds PPD, PPT, ginsenoside-Rg3 (G-Rg3), ginsenoside-Rh2 (G-Rh2), and esculentoside A (EsA) led to significant decreases in the viability of eESCs, particularly PPD (IC50 = 30.64 µM). In vitro and in vivo experiments showed that PPD promoted the expression of progesterone receptor (PR) and downregulated the expression of estrogen receptor α (ERα) in eESCs. Treatment with PPD obviously induced the autophagy of eESCs and reversed the inhibitory effect of estrogen on eESC autophagy. In addition, eESCs pretreated with PPD enhanced the cytotoxic activity of NK cells in response to eESCs. PPD decreased the numbers and suppressed the growth of ectopic lesions in a mouse EMS model. These results suggest that PPD plays a role in anti-EMS activation, possibly by restricting estrogen-mediated autophagy regulation and enhancing the cytotoxicity of NK cells. This result provides a scientific basis for potential therapeutic strategies to treat EMS by PPD or further structural modification.

Pregnancy Luteoma in Ectopic Pregnancy: A Case Report

PubMed Central

Brar, Rupinder Kaur; Bharti, Jyotsna Naresh; Nigam, Jitendra Singh; Sehgal, Sahil; Singh, Hena Paul; Ojha, Pushpanjali

2017-01-01

Background: Pregnancy luteoma is a rare non neoplastic condition of the ovary. It is usually asymptomatic and found incidentally during imaging in pregnancy or during cesarean section. Pregnancy luteoma can also occur after ectopic pregnancy. Case Presentation: A 30 year old female presented to G.B. Pant Hospital, Andaman and Nicobar Islands institute of Medical Sciences, Port Blair in October 2015 with abdominal pain. After initial investigations, exploratory laporotomy was done for ruptured ectopic pregnancy. Enlarged ovary was removed along with the ruptured portion of fallopian tube. Histopathological examination revealed solid aggregates of large cells with abundant eosinophilic cytoplasm; diagnosis of pregnancy luteoma was given. Conclusion: It must be considered in the differential diagnosis of ovarian masses in pregnant females that early diagnosis of this entity may avoid unnecessary radical surgery. PMID:29062798

Invasive mucinous (colloid) adenocarcinoma of ectopic breast tissue in the vulva: a case report.

PubMed

Yin, C; Chapman, J; Tawfik, O

2003-01-01

We present the first case of primary vulvar mucinous adenocarcinoma of ectopic breast origin. The patient is an 84-year-old woman with a mass on the left side of her vulva. A left partial vulvectomy with bilateral inguinal lymph node dissections revealed a mucinous adenocarcinoma that involved the dermis and subcutaneous tissue. The tumor cells were positive for estrogen receptors (ERs), progesterone receptors (PRs), and BRST-1 markers. The clinical and pathologic features, differential diagnosis, and treatment are discussed.

TNFRp55 deficiency promotes the development of ectopic endometriotic-like lesions in mice.

PubMed

Vallcaneras, Sandra; Ghersa, Federica; Bastón, Juan; Delsouc, María Belén; Meresman, Gabriela; Casais, Marilina

2017-09-01

Endometriosis is an inflammatory disease depending on estradiol, with TNF-α being one of the most representative cytokines involved in its pathogenesis. TNF-α acts through its bond to the TNFRp55 and TNFRp75 membrane receptors. The aim of this study was to analyze the effect of the TNFRp55 deficiency on the development of ectopic endometriotic-like lesions. Endometriosis was induced surgically in mice of the C57BL/6 strain, wild type (WT) and TNFRp55-/- (KO). After four weeks, the peritoneal fluid was collected and the lesions were counted, measured with a caliper, removed, weighed, fixed or kept at -80°C. We evaluated the cell proliferation by proliferating cell nuclear antigen (PCNA) immunohistochemistry and apoptosis by TUNEL technique in the ectopic lesions. MMP-2 and MMP-9 activities (factors involved in invasiveness) were measured by zymography in the peritoneal fluid; estradiol and progesterone levels were measured by radioimmunoassay in the lesions and in the peritoneal fluid. We found that in KO animals the mean number of lesions established per mouse, the lesion volume, weight and cell proliferation increased and apoptosis decreased. In addition, the activity of MMP-2 and the estradiol level increased, whereas the progesterone level was not significantly modified. In conclusion, the deficiency of TNFRp55 promoted the establishment and development of endometriosis through an increase in the lesion size and high levels of estradiol which correlate with an increase in the MMP-2 activity. This is evidence of the possible association of the deregulation of the TNFRp55 expression and the survival of the endometriotic tissue in ectopic sites. © 2017 Society for Endocrinology.

Generation of scaffoldless hyaline cartilaginous tissue from human iPSCs.

PubMed

Yamashita, Akihiro; Morioka, Miho; Yahara, Yasuhito; Okada, Minoru; Kobayashi, Tomohito; Kuriyama, Shinichi; Matsuda, Shuichi; Tsumaki, Noriyuki

2015-03-10

Defects in articular cartilage ultimately result in loss of joint function. Repairing cartilage defects requires cell sources. We developed an approach to generate scaffoldless hyaline cartilage from human induced pluripotent stem cells (hiPSCs). We initially generated an hiPSC line that specifically expressed GFP in cartilage when teratoma was formed. We optimized the culture conditions and found BMP2, transforming growth factor β1 (TGF-β1), and GDF5 critical for GFP expression and thus chondrogenic differentiation of the hiPSCs. The subsequent use of scaffoldless suspension culture contributed to purification, producing homogenous cartilaginous particles. Subcutaneous transplantation of the hiPSC-derived particles generated hyaline cartilage that expressed type II collagen, but not type I collagen, in immunodeficiency mice. Transplantation of the particles into joint surface defects in immunodeficiency rats and immunosuppressed mini-pigs indicated that neocartilage survived and had potential for integration into native cartilage. The immunodeficiency mice and rats suffered from neither tumors nor ectopic tissue formation. The hiPSC-derived cartilaginous particles constitute a viable cell source for regenerating cartilage defects. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Generation of Scaffoldless Hyaline Cartilaginous Tissue from Human iPSCs

PubMed Central

Yamashita, Akihiro; Morioka, Miho; Yahara, Yasuhito; Okada, Minoru; Kobayashi, Tomohito; Kuriyama, Shinichi; Matsuda, Shuichi; Tsumaki, Noriyuki

2015-01-01

Summary Defects in articular cartilage ultimately result in loss of joint function. Repairing cartilage defects requires cell sources. We developed an approach to generate scaffoldless hyaline cartilage from human induced pluripotent stem cells (hiPSCs). We initially generated an hiPSC line that specifically expressed GFP in cartilage when teratoma was formed. We optimized the culture conditions and found BMP2, transforming growth factor β1 (TGF-β1), and GDF5 critical for GFP expression and thus chondrogenic differentiation of the hiPSCs. The subsequent use of scaffoldless suspension culture contributed to purification, producing homogenous cartilaginous particles. Subcutaneous transplantation of the hiPSC-derived particles generated hyaline cartilage that expressed type II collagen, but not type I collagen, in immunodeficiency mice. Transplantation of the particles into joint surface defects in immunodeficiency rats and immunosuppressed mini-pigs indicated that neocartilage survived and had potential for integration into native cartilage. The immunodeficiency mice and rats suffered from neither tumors nor ectopic tissue formation. The hiPSC-derived cartilaginous particles constitute a viable cell source for regenerating cartilage defects. PMID:25733017

Enhanced Development of Skeletal Myotubes from Porcine Induced Pluripotent Stem Cells

PubMed Central

Genovese, Nicholas J.; Domeier, Timothy L.; Telugu, Bhanu Prakash V. L.; Roberts, R. Michael

2017-01-01

The pig is recognized as a valuable model in biomedical research in addition to its agricultural importance. Here we describe a means for generating skeletal muscle efficiently from porcine induced pluripotent stem cells (piPSC) in vitro thereby providing a versatile platform for applications ranging from regenerative biology to the ex vivo cultivation of meat. The GSK3B inhibitor, CHIR99021 was employed to suppress apoptosis, elicit WNT signaling events and drive naïve-type piPSC along the mesoderm lineage, and, in combination with the DNA methylation inhibitor 5-aza-cytidine, to activate an early skeletal muscle transcription program. Terminal differentiation was then induced by activation of an ectopically expressed MYOD1. Myotubes, characterized by myofibril development and both spontaneous and stimuli-elicited excitation-contraction coupling cycles appeared within 11 days. Efficient lineage-specific differentiation was confirmed by uniform NCAM1 and myosin heavy chain expression. These results provide an approach for generating skeletal muscle that is potentially applicable to other pluripotent cell lines and to generating other forms of muscle. PMID:28165492

Effect of bone sialoprotein coating of ceramic and synthetic polymer materials on in vitro osteogenic cell differentiation and in vivo bone formation.

PubMed

Schaeren, Stefan; Jaquiéry, Claude; Wolf, Francine; Papadimitropoulos, Adam; Barbero, Andrea; Schultz-Thater, Elke; Heberer, Michael; Martin, Ivan

2010-03-15

In this study, we addressed whether Bone Sialoprotein (BSP) coating of various substrates could enhance the in vitro osteogenic differentiation and in vivo bone formation capacity of human Bone Marrow Stromal Cells (BMSC). Moreover, we tested whether synthetic polymer-based porous scaffolds, despite the absence of a mineral component, could support ectopic bone formation by human BMSC if coated with BSP. Adsorption of recombinant human BSP on tissue culture-treated polystyrene (TCTP), beta-tricalcium phosphate (Osteologic) or synthetic polymer (Polyactive) substrates was dose dependent, but did not consistently accelerate or enhance in vitro BMSC osteogenic differentiation, as assessed by the mRNA expression of osteoblast-related genes. Similarly, BSP coating of porous beta-tricalcium phosphate scaffolds (Skelite) did not improve the efficiency of bone tissue formation following loading with BMSC and ectopic implantation in nude mice. Finally, Polyactive foams seeded with BMSC did not form bone tissue in the same ectopic assay, even if coated with BSP. We conclude that BSP coating of a variety of substrates is not directly associated with an enhancement of osteoprogenitor cell differentiation in vitro or in vivo, and that presentation of BSP on polymeric materials is not sufficient to prime BMSC functional osteoblastic differentiation in vivo. (c) 2009 Wiley Periodicals, Inc.

miR-186 inhibits cell proliferation in multiple myeloma by repressing Jagged1

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

Liu, Zengyan; Department of Hematology, Hospital Affiliated to Binzhou Medical University, 661 Second Huanghe Street, Binzhou 256603; Zhang, Guoqiang

2016-01-15

MicroRNAs (miRNAs) are small, noncoding ribonucleic acids that regulate gene expression by targeting mRNAs for translational repression and degradation. Accumulating experimental evidence supports a causal role of miRNAs in hematology tumorigenesis. However, the specific functions of miRNAs in the pathogenesis of multiple myeloma (MM) remain to be established. In this study, we demonstrated that miR-186 is commonly downregulated in MM cell lines and patient MM cells. Ectopic expression of miR-186 significantly inhibited cell growth, both in vitro and in vivo, and induced cell cycle G{sub 0}/G{sub 1} arrest. Furthermore, miR-186 induced downregulation of Jagged1 protein expression by directly targeting its 3′-untranslated regionmore » (3′-UTR). Conversely, overexpression of Jagged1 rescued cells from miR-186-induced growth inhibition. Our collective results clearly indicate that miR-186 functions as a tumor suppressor in MM, supporting its potential as a therapeutic target for the disease. - Highlights: • miR-186 expression is decreased in MM. • miR-186 inhibits MM cell proliferation in vitro and in vivo. • Jagged1 is regulated by miR-186. • Overexpression of Jagged1 reverses the effects of miR-186.« less

Osteoprotegerin Promotes Cementoblastic Activity of Murine Cementoblast Cell Line in vitro.

PubMed

Zhang, Ying Ying; Zhao, Hua Xiang; Chen, Zhi Bin; Lin, Jiu Xiang; Liu, Yan

2016-06-01

To investigate the effect of osteoprotegerin (OPG) on the cementoblastic activity of a clonal population of immortalised murine cementoblasts (OCCM-30) in vitro. OCCM-30 cells were transiently transfected with the mouse OPG using the Avalanche transfection reagent. The ectopic expression of OPG was confirmed by enzyme-linked immunosorbent assay and quantitative polymerase chain reaction. The cell counting Kit-8 assay was used to investigate the effect of OPG on cell proliferation. The expression levels of cementoblastic-related mRNA and protein in the transfected OCCM-30 cells were detected using real-time PCR, Western blotting and immunohistochemical staining. Satisfactory transfection efficiency was observed 48 h after transfection. The results of the cell proliferation assay indicated that the expansion rate of the OPG transfection group was greater than that of the control group at both 72 h and 96 h. The mRNA levels of osterix (Osx), protein kinase B (Akt1), cementum attachment protein (CAP) and osteopontin (Opn) were significantly upregulated (P < 0.05) in the OPG group. Protein levels of OPN, bone sialoprotein II (BSP II), osteocalcin (OC) and CAP, which are responsible for osteogenetic and cementoblastic activity, were significantly increased in the OPG-overexpressing group. Overexpression of OPG in OCCM-30 cells promotes cementoblastic activity.

Multiplexing clonality: combining RGB marking and genetic barcoding

PubMed Central

Cornils, Kerstin; Thielecke, Lars; Hüser, Svenja; Forgber, Michael; Thomaschewski, Michael; Kleist, Nadja; Hussein, Kais; Riecken, Kristoffer; Volz, Tassilo; Gerdes, Sebastian; Glauche, Ingmar; Dahl, Andreas; Dandri, Maura; Roeder, Ingo; Fehse, Boris

2014-01-01

RGB marking and DNA barcoding are two cutting-edge technologies in the field of clonal cell marking. To combine the virtues of both approaches, we equipped LeGO vectors encoding red, green or blue fluorescent proteins with complex DNA barcodes carrying color-specific signatures. For these vectors, we generated highly complex plasmid libraries that were used for the production of barcoded lentiviral vector particles. In proof-of-principle experiments, we used barcoded vectors for RGB marking of cell lines and primary murine hepatocytes. We applied single-cell polymerase chain reaction to decipher barcode signatures of individual RGB-marked cells expressing defined color hues. This enabled us to prove clonal identity of cells with one and the same RGB color. Also, we made use of barcoded vectors to investigate clonal development of leukemia induced by ectopic oncogene expression in murine hematopoietic cells. In conclusion, by combining RGB marking and DNA barcoding, we have established a novel technique for the unambiguous genetic marking of individual cells in the context of normal regeneration as well as malignant outgrowth. Moreover, the introduction of color-specific signatures in barcodes will facilitate studies on the impact of different variables (e.g. vector type, transgenes, culture conditions) in the context of competitive repopulation studies. PMID:24476916

TRIM67 Protein Negatively Regulates Ras Activity through Degradation of 80K-H and Induces Neuritogenesis*

PubMed Central

Yaguchi, Hiroaki; Okumura, Fumihiko; Takahashi, Hidehisa; Kano, Takahiro; Kameda, Hiroyuki; Uchigashima, Motokazu; Tanaka, Shinya; Watanabe, Masahiko; Sasaki, Hidenao; Hatakeyama, Shigetsugu

2012-01-01

Tripartite motif (TRIM)-containing proteins, which are defined by the presence of a common domain structure composed of a RING finger, one or two B-box motifs and a coiled-coil motif, are involved in many biological processes including innate immunity, viral infection, carcinogenesis, and development. Here we show that TRIM67, which has a TRIM motif, an FN3 domain and a SPRY domain, is highly expressed in the cerebellum and that TRIM67 interacts with PRG-1 and 80K-H, which is involved in the Ras-mediated signaling pathway. Ectopic expression of TRIM67 results in degradation of endogenous 80K-H and attenuation of cell proliferation and enhances neuritogenesis in the neuroblastoma cell line N1E-115. Furthermore, morphological and biological changes caused by knockdown of 80K-H are similar to those observed by overexpression of TRIM67. These findings suggest that TRIM67 regulates Ras signaling via degradation of 80K-H, leading to neural differentiation including neuritogenesis. PMID:22337885

TRIM67 protein negatively regulates Ras activity through degradation of 80K-H and induces neuritogenesis.

PubMed

Yaguchi, Hiroaki; Okumura, Fumihiko; Takahashi, Hidehisa; Kano, Takahiro; Kameda, Hiroyuki; Uchigashima, Motokazu; Tanaka, Shinya; Watanabe, Masahiko; Sasaki, Hidenao; Hatakeyama, Shigetsugu

2012-04-06

Tripartite motif (TRIM)-containing proteins, which are defined by the presence of a common domain structure composed of a RING finger, one or two B-box motifs and a coiled-coil motif, are involved in many biological processes including innate immunity, viral infection, carcinogenesis, and development. Here we show that TRIM67, which has a TRIM motif, an FN3 domain and a SPRY domain, is highly expressed in the cerebellum and that TRIM67 interacts with PRG-1 and 80K-H, which is involved in the Ras-mediated signaling pathway. Ectopic expression of TRIM67 results in degradation of endogenous 80K-H and attenuation of cell proliferation and enhances neuritogenesis in the neuroblastoma cell line N1E-115. Furthermore, morphological and biological changes caused by knockdown of 80K-H are similar to those observed by overexpression of TRIM67. These findings suggest that TRIM67 regulates Ras signaling via degradation of 80K-H, leading to neural differentiation including neuritogenesis.

ATXN1L, CIC, and ETS Transcription Factors Modulate Sensitivity to MAPK Pathway Inhibition.

PubMed

Wang, Belinda; Krall, Elsa Beyer; Aguirre, Andrew James; Kim, Miju; Widlund, Hans Ragnar; Doshi, Mihir Bhavik; Sicinska, Ewa; Sulahian, Rita; Goodale, Amy; Cowley, Glenn Spencer; Piccioni, Federica; Doench, John Gerard; Root, David Edward; Hahn, William Chun

2017-02-07

Intrinsic resistance and RTK-RAS-MAPK pathway reactivation has limited the effectiveness of MEK and RAF inhibitors (MAPKi) in RAS- and RAF-mutant cancers. To identify genes that modulate sensitivity to MAPKi, we performed genome-scale CRISPR-Cas9 loss-of-function screens in two KRAS mutant pancreatic cancer cell lines treated with the MEK1/2 inhibitor trametinib. Loss of CIC, a transcriptional repressor of ETV1, ETV4, and ETV5, promoted survival in the setting of MAPKi in cancer cells derived from several lineages. ATXN1L deletion, which reduces CIC protein, or ectopic expression of ETV1, ETV4, or ETV5 also modulated sensitivity to trametinib. ATXN1L expression inversely correlates with response to MAPKi inhibition in clinical studies. These observations identify the ATXN1L-CIC-ETS transcription factor axis as a mediator of resistance to MAPKi. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

[Three-dimensional parallel collagen scaffold promotes tendon extracellular matrix formation].

PubMed

Zheng, Zefeng; Shen, Weiliang; Le, Huihui; Dai, Xuesong; Ouyang, Hongwei; Chen, Weishan

2016-03-01

To investigate the effects of three-dimensional parallel collagen scaffold on the cell shape, arrangement and extracellular matrix formation of tendon stem cells. Parallel collagen scaffold was fabricated by unidirectional freezing technique, while random collagen scaffold was fabricated by freeze-drying technique. The effects of two scaffolds on cell shape and extracellular matrix formation were investigated in vitro by seeding tendon stem/progenitor cells and in vivo by ectopic implantation. Parallel and random collagen scaffolds were produced successfully. Parallel collagen scaffold was more akin to tendon than random collagen scaffold. Tendon stem/progenitor cells were spindle-shaped and unified orientated in parallel collagen scaffold, while cells on random collagen scaffold had disorder orientation. Two weeks after ectopic implantation, cells had nearly the same orientation with the collagen substance. In parallel collagen scaffold, cells had parallel arrangement, and more spindly cells were observed. By contrast, cells in random collagen scaffold were disorder. Parallel collagen scaffold can induce cells to be in spindly and parallel arrangement, and promote parallel extracellular matrix formation; while random collagen scaffold can induce cells in random arrangement. The results indicate that parallel collagen scaffold is an ideal structure to promote tendon repairing.

Progenitors of Secondary Crest Myofibroblasts are Developmentally Committed in Early Lung Mesoderm

PubMed Central

Li, Changgong; Li, Min; Li, Sha; Xing, Yiming; Yang, Chang-Yo; Li, Aimin; Borok, Zea; De Langhe, Stijn; Minoo, Parviz

2015-01-01

Development of the mammalian lung is predicated on cross-communications between two highly interactive tissues, the endodermally-derived epithelium and the mesodermally-derived pulmonary mesenchyme. While much attention has been paid the lung epithelium, the pulmonary mesenchyme, partly due to lack of specific tractable markers remains under-investigated. The lung mesenchyme is derived from the lateral plate mesoderm and is the principal recipient of Hedgehog (Hh) signaling, a morphogenetic network that regulates multiple aspects of embryonic development. Using the Hh-responsive Gli1-creERT2 mouse line, we identified the mesodermal targets of Hh signaling at various time points during embryonic and postnatal lung development. Cell lineage analysis showed these cells serve as progenitors to contribute to multiple lineages of mesodermally-derived differentiated cell types that include parenchymal or interstitial myofibroblasts, parabronchial and perivascular smooth muscle as well as rare populations of cells within the mesothelium. Most importantly, Gli1-creERT2 identified the progenitors of secondary crest myofibroblasts, a hitherto intractable cell type that plays a key role in alveolar formation, a vital process about which little is currently known. Transcriptome analysis of Hh-targeted progenitor cells transitioning from the pseudoglandular to the saccular phase of lung development revealed important modulations of key signaling pathways. Amongst these, there was significant down-regulation of canonical WNT signaling. Ectopic stabilization of β-Catenin via inactivation of Apc by Gli1-creERT2 expanded the Hh-targeted progenitor pools, which caused the formation of fibroblastic masses within the lung parenchyma. The Gli1-creERT2 mouse line represents a novel tool in the analysis of mesenchymal cell biology and alveolar formation during lung development. PMID:25448080

Hsa-miR-875-5p exerts tumor suppressor function through down-regulation of EGFR in colorectal carcinoma (CRC)

PubMed Central

Li, Qi; Xue, Peng; Chen, Zhixiao; Dong, Xiao; Xue, Ying

2016-01-01

Hsa-miRNA-875-5p (miR-875-5p) has recently been discovered to have anticancer efficacy in different organs. However, the role of miR-875-5p on colorectal carcinoma (CRC) is still ambiguous. In this study, we investigated the role of miR-875-5p on the development of CRC. The results indicated that miR-875-5p was significantly down-regulated in primary tumor tissues and very low levels were found in CRC cell lines. Ectopic expression of miR-875-5p in CRC cell lines significantly suppressed cell growth as evidenced by cell viability assay, colony formation assay and BrdU staining, through inhibition of cyclin D1, cyclin D2, CDK4 and up-regulation of p57(Kip2) and p21(Waf1/Cip1). In addition, miR-875-5p induced apoptosis, as indicated by concomitantly with up-regulation of key apoptosis protein cleaved caspase-3, and down-regulation of anti-apoptosis protein Bcl2. Moreover, miR-875-5p inhibited cellular migration and invasiveness through inhibition of matrix metalloproteinases (MMP)-7 and MMP-9. Further, oncogene EGFR was revealed to be a putative target of miR-875-5p, which was inversely correlated with miR-875-5p expression in CRC. Taken together, our results demonstrated that miR-875-5p played a pivotal role on CRC through inhibiting cell proliferation, migration, invasion, and promoting apoptosis by targeting oncogenic EGFR. PMID:27302926

Hsa-miR-875-5p exerts tumor suppressor function through down-regulation of EGFR in colorectal carcinoma (CRC).

PubMed

Zhang, Tiening; Cai, Xun; Li, Qi; Xue, Peng; Chen, Zhixiao; Dong, Xiao; Xue, Ying

2016-07-05

Hsa-miRNA-875-5p (miR-875-5p) has recently been discovered to have anticancer efficacy in different organs. However, the role of miR-875-5p on colorectal carcinoma (CRC) is still ambiguous. In this study, we investigated the role of miR-875-5p on the development of CRC. The results indicated that miR-875-5p was significantly down-regulated in primary tumor tissues and very low levels were found in CRC cell lines. Ectopic expression of miR-875-5p in CRC cell lines significantly suppressed cell growth as evidenced by cell viability assay, colony formation assay and BrdU staining, through inhibition of cyclin D1, cyclin D2, CDK4 and up-regulation of p57(Kip2) and p21(Waf1/Cip1). In addition, miR-875-5p induced apoptosis, as indicated by concomitantly with up-regulation of key apoptosis protein cleaved caspase-3, and down-regulation of anti-apoptosis protein Bcl2. Moreover, miR-875-5p inhibited cellular migration and invasiveness through inhibition of matrix metalloproteinases (MMP)-7 and MMP-9. Further, oncogene EGFR was revealed to be a putative target of miR-875-5p, which was inversely correlated with miR-875-5p expression in CRC. Taken together, our results demonstrated that miR-875-5p played a pivotal role on CRC through inhibiting cell proliferation, migration, invasion, and promoting apoptosis by targeting oncogenic EGFR.

PAXIP1 potentiates the combination of WEE1 inhibitor AZD1775 and platinum agents in lung cancer

PubMed Central

Jhuraney, Ankita; Woods, Nicholas T.; Wright, Gabriela; Rix, Lily; Kinose, Fumi; Kroeger, Jodi L.; Remily-Wood, Elizabeth; Cress, W. Douglas; Koomen, John M.; Brantley, Stephen G.; Gray, Jhanelle E.; Haura, Eric B.; Rix, Uwe; Monteiro, Alvaro N.

2016-01-01

The DNA damage response (DDR) involves a complex network of signaling events mediated by modular protein domains such as the BRCT (BRCA1 C-terminal) domain. Thus, proteins that interact with BRCT domains and are a part of the DDR constitute potential targets for sensitization to DNA damaging chemotherapy agents. We performed a pharmacological screen to evaluate seventeen kinases, identified in a BRCT-mediated interaction network as targets to enhance platinum-based chemotherapy in lung cancer. Inhibition of mitotic kinase WEE1 was found to have the most effective response in combination with platinum compounds in lung cancer cell lines. In the BRCT-mediated interaction network, WEE1 was found in complex with PAXIP1, a protein containing six BRCT domains involved in transcription and in the cellular response to DNA damage. We show that PAXIP1 BRCT domains regulate WEE1-mediated phosphorylation of CDK1. Further, ectopic expression of PAXIP1 promotes enhanced caspase 3-mediated apoptosis in cells treated with WEE1 inhibitor AZD1775 (formerly, MK-1775) and cisplatin compared with cells treated with AZD1775 alone. Cell lines and patient-derived xenograft models expressing both PAXIP1 and WEE1 exhibited synergistic effects of AZD1775 and cisplatin. In summary, PAXIP1 is involved in sensitizing lung cancer cells to the WEE1 inhibitor AZD1775 in combination with platinum-based treatment. We propose that WEE1 and PAXIP1 levels may be used as mechanism-based biomarkers of response when WEE1 inhibitor AZD1775 is combined with DNA damaging agents. PMID:27196765

A modified GFP facilitates counting membrane protein subunits by step-wise photobleaching in Arabidopsis.

PubMed

Song, Kai; Xue, Yiqun; Wang, Xiaohua; Wan, Yinglang; Deng, Xin; Lin, Jinxing

2017-06-01

Membrane proteins exert functions by forming oligomers or molecular complexes. Currently, step-wise photobleaching has been applied to count the fluorescently labelled subunits in plant cells, for which an accurate and reliable control is required to distinguish individual subunits and define the basal fluorescence. However, the common procedure using immobilized GFP molecules is obviously not applicable for analysis in living plant cells. Using the spatial intensity distribution analysis (SpIDA), we found that the A206K mutation reduced the dimerization of GFP molecules. Further ectopic expression of Myristoyl-GFP A206K driven by the endogenous AtCLC2 promoter allowed imaging of individual molecules at a low expression level. As a result, the percentage of dimers in the transgenic pCLC2::Myristoyl-mGFP A206K line was significantly reduced in comparison to that of the pCLC2::Myristoyl-GFP line, confirming its application in defining the basal fluorescence intensity of GFP. Taken together, our results demonstrated that pCLC2::Myristoyl-mGFP A206K can be used as a standard control for monomer GFP, facilitating the analysis of the step-wise photobleaching of membrane proteins in Arabidopsis thaliana. Copyright © 2017 Elsevier GmbH. All rights reserved.

Cyclin D1 Downregulation Contributes to Anti-Cancer Effect of Isorhapontigenin (ISO) on Human Bladder Cancer Cells

PubMed Central

Fang, Yong; Cao, Zipeng; Hou, Qi; Ma, Chen; Yao, Chunsuo; Li, Jingxia; Wu, Xue-Ru; Huang, Chuanshu

2013-01-01

Isorhapontigenin (ISO) is a new derivative of stilbene compound that was isolated from the Chinese herb Gnetum Cleistostachyum, and has been used for treatment of bladder cancers for centuries. In our current studies, we have explored the potential inhibitory effect and molecular mechanisms underlying ISO anti-cancer effects on anchorage-independent growth of human bladder cancer cell lines. We found that ISO showed a significant inhibitory effect on human bladder cancer cell growth and was accompanied with related cell cycle G0/G1 arrest as well as downregulation of Cyclin D1 expression at the transcriptional level in UMUC3 and RT112 cells. Further studies identified that ISO down-regulated Cyclin D1 gene transcription via inhibition of SP1 transactivation. Moreover, ectopic expression of GFP-Cyclin D1 rendered UMUC3 cells resistant to induction of cell cycle G0/G1 arrest and inhibition of cancer cell anchorage-independent growth by ISO treatment. Together, our studies demonstrate that ISO is an active compound that mediates for Gnetum Cleistostachyum’s induction of cell cycle G0/G1 arrest and inhibition of cancer cell anchorage-independent growth through down-regulating SP1/Cyclin D1 axis in bladder cancer cells. Our studies provide a novel insight into understanding the anti-cancer activity of the Chinese herb Gnetum Cleistostachyum and its isolate ISO. PMID:23723126

Induced stem cell neoplasia in a cnidarian by ectopic expression of a POU domain transcription factor.

PubMed

Millane, R Cathriona; Kanska, Justyna; Duffy, David J; Seoighe, Cathal; Cunningham, Stephen; Plickert, Günter; Frank, Uri

2011-06-01

The evolutionary origin of stem cell pluripotency is an unresolved question. In mammals, pluripotency is limited to early embryos and is induced and maintained by a small number of key transcription factors, of which the POU domain protein Oct4 is considered central. Clonal invertebrates, by contrast, possess pluripotent stem cells throughout their life, but the molecular mechanisms that control their pluripotency are poorly defined. To address this problem, we analyzed the expression pattern and function of Polynem (Pln), a POU domain gene from the marine cnidarian Hydractinia echinata. We show that Pln is expressed in the embryo and adult stem cells of the animal and that ectopic expression in epithelial cells induces stem cell neoplasms and loss of epithelial tissue. Neoplasm cells downregulated the transgene but expressed the endogenous Pln gene and also Nanos, Vasa, Piwi and Myc, which are all known cnidarian stem cell markers. Retinoic acid treatment caused downregulation of Pln and the differentiation of neoplasm cells to neurosensory and epithelial cells. Pln downregulation by RNAi led to differentiation. Collectively, our results suggest an ancient role of POU proteins as key regulators of animal stem cells.

Estrogen receptor α dependent regulation of estrogen related receptor β and its role in cell cycle in breast cancer.

PubMed

Madhu Krishna, B; Chaudhary, Sanjib; Mishra, Dipti Ranjan; Naik, Sanoj K; Suklabaidya, S; Adhya, A K; Mishra, Sandip K

2018-05-30

Breast cancer (BC) is highly heterogeneous with ~ 60-70% of estrogen receptor positive BC patient's response to anti-hormone therapy. Estrogen receptors (ERs) play an important role in breast cancer progression and treatment. Estrogen related receptors (ERRs) are a group of nuclear receptors which belong to orphan nuclear receptors, which have sequence homology with ERs and share target genes. Here, we investigated the possible role and clinicopathological importance of ERRβ in breast cancer. Estrogen related receptor β (ERRβ) expression was examined using tissue microarray slides (TMA) of Breast Carcinoma patients with adjacent normal by immunohistochemistry and in breast cancer cell lines. In order to investigate whether ERRβ is a direct target of ERα, we investigated the expression of ERRβ in short hairpin ribonucleic acid knockdown of ERα breast cancer cells by western blot, qRT-PCR and RT-PCR. We further confirmed the binding of ERα by electrophoretic mobility shift assay (EMSA), chromatin immunoprecipitation (ChIP), Re-ChIP and luciferase assays. Fluorescence-activated cell sorting analysis (FACS) was performed to elucidate the role of ERRβ in cell cycle regulation. A Kaplan-Meier Survival analysis of GEO dataset was performed to correlate the expression of ERRβ with survival in breast cancer patients. Tissue microarray (TMA) analysis showed that ERRβ is significantly down-regulated in breast carcinoma tissue samples compared to adjacent normal. ER + ve breast tumors and cell lines showed a significant expression of ERRβ compared to ER-ve tumors and cell lines. Estrogen treatment significantly induced the expression of ERRβ and it was ERα dependent. Mechanistic analyses indicate that ERα directly targets ERRβ through estrogen response element and ERRβ also mediates cell cycle regulation through p18, p21 cip and cyclin D1 in breast cancer cells. Our results also showed the up-regulation of ERRβ promoter activity in ectopically co-expressed ERα and ERRβ breast cancer cell lines. Fluorescence-activated cell sorting analysis (FACS) showed increased G0/G1 phase cell population in ERRβ overexpressed MCF7 cells. Furthermore, ERRβ expression was inversely correlated with overall survival in breast cancer. Collectively our results suggest cell cycle and tumor suppressor role of ERRβ in breast cancer cells which provide a potential avenue to target ERRβ signaling pathway in breast cancer. Our results indicate that ERRβ is a negative regulator of cell cycle and a possible tumor suppressor in breast cancer. ERRβ could be therapeutic target for the treatment of breast cancer.

Dietary effects of cotton tissue expressing germin like protein on beet armyworm (Lepidoptera: Noctuidae) growth, survival and pupation

USDA-ARS?s Scientific Manuscript database

Transgenic cotton lines that ectopically express a cotton germin-like protein (ABP) were screened for resistance/tolerance factors to the beet armyworm (BAW) Spodoptera exigua (Hubner) via feeding assays. The number of BAW eggs that successfully hatched was not statistically different at 72 h observ...

Cell cycle stage-specific differential expression of topoisomerase I in tobacco BY-2 cells and its ectopic overexpression and knockdown unravels its crucial role in plant morphogenesis and development.

PubMed

Singh, Badri Nath; Mudgil, Yashwanti; John, Riffat; Achary, V Mohan Murali; Tripathy, Manas Kumar; Sopory, Sudhir K; Reddy, Malireddy K; Kaul, Tanushri

2015-11-01

DNA topoisomerases catalyze the inter-conversion of different topological forms of DNA. Cell cycle coupled differential accumulation of topoisomerase I (Topo I) revealed biphasic expression maximum at S-phase and M/G1-phase of cultured synchronized tobacco BY-2 cells. This suggested its active role in resolving topological constrains during DNA replication (S-phase) and chromosome decondensation (M/G1 phase). Immuno-localization revealed high concentrations of Topo I in nucleolus. Propidium iodide staining and Br-UTP incorporation patterns revealed direct correlation between immunofluorescence intensity and rRNA transcription activity within nucleolus. Immuno-stained chromosomes during metaphase and anaphase suggested possible role of Topo I in resolving topological constrains during mitotic chromosome condensation. Inhibitor studies showed that in comparison to Topo I, Topo II was essential in resolving topological constrains during chromosome condensation. Probably, Topo II substituted Topo I functioning to certain extent during chromosome condensation, but not vice-versa. Transgenic Topo I tobacco lines revealed morphological abnormalities and highlighted its crucial role in plant morphogenesis and development. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Transcription factor Sox4 is required for PUMA-mediated apoptosis induced by histone deacetylase inhibitor, TSA.

PubMed

Jang, Sang-Min; Kang, Eun-Jin; Kim, Jung-Woong; Kim, Chul-Hong; An, Joo-Hee; Choi, Kyung-Hee

2013-08-23

PUMA is a crucial regulator of apoptotic cell death mediated by p53-dependent and p53-independent mechanisms. In many cancer cells, PUMA expression is induced in response to DNA-damaging reagent in a p53-dependent manner. However, few studies have investigated transcription factors that lead to the induction of PUMA expression via p53-independent apoptotic signaling. In this study, we found that the transcription factor Sox4 increased PUMA expression in response to trichostatin A (TSA), a histone deacetylase inhibitor in the p53-null human lung cancer cell line H1299. Ectopic expression of Sox4 led to the induction of PUMA expression at the mRNA and protein levels, and TSA-mediated up-regulation of PUMA transcription was repressed by the knockdown of Sox4. Using luciferase assays and chromatin immunoprecipitation, we also determined that Sox4 recruits p300 on the PUMA promoter region and increases PUMA gene expression in response to TSA treatment. Taken together, these results suggest that Sox4 is required for p53-independent apoptotic cell death mediated by PUMA induction via TSA treatment. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

Alternative Lengthening of Telomeres Mediated by Mitotic DNA Synthesis Engages Break-Induced Replication Processes

PubMed Central

Min, Jaewon; Wright, Woodring E.

2017-01-01

ABSTRACT Alternative lengthening of telomeres (ALT) is a telomerase-independent telomere maintenance mechanism that occurs in a subset of cancers. By analyzing telomerase-positive cells and their human TERC knockout-derived ALT human cell lines, we show that ALT cells harbor more fragile telomeres representing telomere replication problems. ALT-associated replication defects trigger mitotic DNA synthesis (MiDAS) at telomeres in a RAD52-dependent, but RAD51-independent, manner. Telomeric MiDAS is a conservative DNA synthesis process, potentially mediated by break-induced replication, similar to type II ALT survivors in Saccharomyces cerevisiae. Replication stresses induced by ectopic oncogenic expression of cyclin E, G-quadruplexes, or R-loop formation facilitate the ALT pathway and lead to telomere clustering, a hallmark of ALT cancers. The TIMELESS/TIPIN complex suppresses telomere clustering and telomeric MiDAS, whereas the SMC5/6 complex promotes them. In summary, ALT cells exhibit more telomere replication defects that result in persistent DNA damage responses at telomeres, leading to the engagement of telomeric MiDAS (spontaneous mitotic telomere synthesis) that is triggered by DNA replication stress, a potential driver of genomic duplications in cancer. PMID:28760773

Systems-level effects of ectopic galectin-7 reconstitution in cervical cancer and its microenvironment.

PubMed

Higareda-Almaraz, Juan Carlos; Ruiz-Moreno, Juan S; Klimentova, Jana; Barbieri, Daniela; Salvador-Gallego, Raquel; Ly, Regina; Valtierra-Gutierrez, Ilse A; Dinsart, Christiane; Rabinovich, Gabriel A; Stulik, Jiri; Rösl, Frank; Rincon-Orozco, Bladimiro

2016-08-24

Galectin-7 (Gal-7) is negatively regulated in cervical cancer, and appears to be a link between the apoptotic response triggered by cancer and the anti-tumoral activity of the immune system. Our understanding of how cervical cancer cells and their molecular networks adapt in response to the expression of Gal-7 remains limited. Meta-analysis of Gal-7 expression was conducted in three cervical cancer cohort studies and TCGA. In silico prediction and bisulfite sequencing were performed to inquire epigenetic alterations. To study the effect of Gal-7 on cervical cancer, we ectopically re-expressed it in the HeLa and SiHa cervical cancer cell lines, and analyzed their transcriptome and SILAC-based proteome. We also examined the tumor and microenvironment host cell transcriptomes after xenotransplantation into immunocompromised mice. Differences between samples were assessed with the Kruskall-Wallis, Dunn's Multiple Comparison and T tests. Kaplan-Meier and log-rank tests were used to determine overall survival. Gal-7 was constantly downregulated in our meta-analysis (p < 0.0001). Tumors with combined high Gal-7 and low galectin-1 expression (p = 0.0001) presented significantly better prognoses (p = 0.005). In silico and bisulfite sequencing assays showed de novo methylation in the Gal-7 promoter and first intron. Cells re-expressing Gal-7 showed a high apoptosis ratio (p < 0.05) and their xenografts displayed strong growth retardation (p < 0.001). Multiple gene modules and transcriptional regulators were modulated in response to Gal-7 reconstitution, both in cervical cancer cells and their microenvironments (FDR < 0.05 %). Most of these genes and modules were associated with tissue morphogenesis, metabolism, transport, chemokine activity, and immune response. These functional modules could exert the same effects in vitro and in vivo, even despite different compositions between HeLa and SiHa samples. Gal-7 re-expression affects the regulation of molecular networks in cervical cancer that are involved in diverse cancer hallmarks, such as metabolism, growth control, invasion and evasion of apoptosis. The effect of Gal-7 extends to the microenvironment, where networks involved in its configuration and in immune surveillance are particularly affected.

Concise Review: One Stone for Multiple Birds: Generating Universally Compatible Human Embryonic Stem Cells.

PubMed

Zheng, Dejin; Wang, Xiaofang; Xu, Ren-He

2016-09-01

With ongoing clinical trials, human embryonic stem cells (hESCs) have shown substantial potential for regenerative medicine. However, due to the mismatch of human leukocyte antigens (HLAs) between hESC-derived allografts and recipients, immunosuppressant regimens must be used to prevent immune rejection of the grafts. Considerable efforts have been devoted to overcoming this hurdle via the derivation and banking of human nuclear transfer ESCs, parthenogenetic ESCs, and induced pluripotent stem cells. However, ethical and safety concerns remain, hindering the application of these types of pluripotent cells. Other approaches have recently been explored to generate universally compatible hESCs through the silencing or deletion of HLAs or genes essential for HLA expression, including β-2-microglobulin and class-II MHC transactivator, as well as the induction of immunosuppression via the ectopic expression of non-classical HLAs (e.g., HLA-E and -G), cytotoxic T lymphocyte antigen 4 fused with immunoglobulin, and programmed death ligand-1. In this review, we introduce developments in this line of research and discuss strategies to reduce the tumorigenic concerns regarding hESCs, especially after they acquire the capability to escape immune surveillance. Stem Cells 2016;34:2269-2275. © 2016 The Authors STEM CELLS published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

Decoy receptor 3 promotes cell adhesion and enhances endometriosis development.

PubMed

Tsai, Hsiao-Wen; Huang, Ming-Ting; Wang, Peng-Hui; Huang, Ben-Shian; Chen, Yi-Jen; Hsieh, Shie-Liang

2018-02-01

Endometriosis is a multifactorial inflammatory disease with persistent activation of the nuclear factor-κB (NF-κB) signalling pathway. Aberrant adhesion of endometrium is the essential step in the progression of endometriosis, but the molecular mechanism of ectopic growth of endometrium is still unclear. Decoy receptor 3 (DcR3)/TNFRSF6B, a pleiotropic immunomodulator regulated by oestrogen, is able to activate focal adhesion kinase to promote cell adhesion. We found that DcR3 is upregulated in human ectopic endometrial cells via activation of the Akt-NF-κB signalling pathway, and its expression level correlates positively with that of the adhesion molecules intercellular adhesion molecule 1 (ICAM-1) and homing cell adhesion molecule (HCAM; CD44). In a multivariate regression model, DcR3 expression level was the most significant parameter associated with endometriosis severity. Knockdown of DcR3 not only downregulated the expression of ICAM-1 and HCAM, but also reduced cell adhesion and migration. In vivo investigation further showed that DcR3 promoted the growth and spread of endometrium, whereas knockdown of DcR3 by lentivirus-delivered short hairpin RNA inhibited ectopic adhesion of endometrium and abrogated endometriosis progression. These observations are in support of DcR3 playing a critical role in the pathogenesis of endometriosis, and the inhibition of DcR3 expression being a promising approach for the treatment of endometriosis. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

ROCK1-directed basement membrane positioning coordinates epithelial tissue polarity.

PubMed

Daley, William P; Gervais, Elise M; Centanni, Samuel W; Gulfo, Kathryn M; Nelson, Deirdre A; Larsen, Melinda

2012-01-01

The basement membrane is crucial for epithelial tissue organization and function. However, the mechanisms by which basement membrane is restricted to the basal periphery of epithelial tissues and the basement membrane-mediated signals that regulate coordinated tissue organization are not well defined. Here, we report that Rho kinase (ROCK) controls coordinated tissue organization by restricting basement membrane to the epithelial basal periphery in developing mouse submandibular salivary glands, and that ROCK inhibition results in accumulation of ectopic basement membrane throughout the epithelial compartment. ROCK-regulated restriction of PAR-1b (MARK2) localization in the outer basal epithelial cell layer is required for basement membrane positioning at the tissue periphery. PAR-1b is specifically required for basement membrane deposition, as inhibition of PAR-1b kinase activity prevents basement membrane deposition and disrupts overall tissue organization, and suppression of PAR-1b together with ROCK inhibition prevents interior accumulations of basement membrane. Conversely, ectopic overexpression of wild-type PAR-1b results in ectopic interior basement membrane deposition. Significantly, culture of salivary epithelial cells on exogenous basement membrane rescues epithelial organization in the presence of ROCK1 or PAR-1b inhibition, and this basement membrane-mediated rescue requires functional integrin β1 to maintain epithelial cell-cell adhesions. Taken together, these studies indicate that ROCK1/PAR-1b-dependent regulation of basement membrane placement is required for the coordination of tissue polarity and the elaboration of tissue structure in the developing submandibular salivary gland.

Inhibition of BET Bromodomain Targets Genetically Diverse Glioblastoma

PubMed Central

Cheng, Zhixiang; Gong, Yuanying; Ma, Yufang; Lu, Kaihua; Lu, Xiang; Pierce, Larry A.; Thompson, Reid C.; Muller, Susanne; Knapp, Stefan; Wang, Jialiang

2014-01-01

Purpose Glioblastoma is refractory to conventional therapies. The bromodomain and extraterminal domain (BET) proteins are epigenetic readers that selectively bind to acetylated lysine residues on histone tails. These proteins recently emerged as important therapeutic targets in NUT midline carcinoma and several types of hematopoietic cancers. In this study, the therapeutic potential of a novel BET bromodomain inhibitor, JQ1, was assessed in a panel of genetically heterogeneous glioblastoma samples. Experimental Design The antineoplastic effects of JQ1 were shown using ex vivo cultures derived from primary glioblastoma xenograft lines and surgical specimens of different genetic background. The in vivo efficacy was assessed in orthotopic glioblastoma tumors. Results We showed that JQ1 induced marked G1 cell-cycle arrest and apoptosis, which was phenocopied by knockdown of individual BET family members. JQ1 treatment resulted in significant changes in expression of genes that play important roles in glioblastoma such as c-Myc, p21CIP1/WAF1, hTERT, Bcl-2, and Bcl-xL. Unlike the observations in some hematopoietic cancer cell lines, exogenous c-Myc did not significantly protect glioblastoma cells against JQ1. In contrast, ectopically expressed Bcl-xL partially rescued cells from JQ1-induced apoptosis, and knockdown of p21CIP1/WAF1 attenuated JQ1-induced cell-cycle arrest. Cells genetically engineered for Akt hyperactivation or p53/Rb inactivation did not compromise JQ1 efficacy, suggesting that these frequently mutated signaling pathways may not confer resistance to JQ1. Furthermore, JQ1 significantly repressed growth of orthotopic glioblastoma tumors. Conclusion Our results suggest potentially broad therapeutic use of BET bromodomain inhibitors for treating genetically diverse glioblastoma tumors. PMID:23403638

miR-1271 inhibits migration, invasion and epithelial-mesenchymal transition by targeting ZEB1 and TWIST1 in pancreatic cancer cells

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

Liu, Huaize; Wang, Han; Liu, Xiaoxiao

Pancreatic cancer (PC) remains one of the most lethal types of cancer in adults. The purpose of this study was to determine the role of miR-1271 in regulation of epithelial mesenchymal transition (EMT) and metastasis of pancreatic cancer cells. miR-1271 was identified to be significantly down-regulated in PC tissues by miRNA array. Also, an increase of EMT-regulators ZEB1 and TWIST1 expression level is accompanied by a decrease of miR-1271. We showed that expression of miR-1271 was significantly down-regulated in PC tissues as compared with that in normal tissues. In addition, our results showed that miR-1271 expression levels were decreased whilemore » ZEB1 and TWIST1 expression levels were increased in detected PC cell lines. Moreover, ectopic expression of miR-1271 suppressed and antagomiR-1271 promoted proliferation, migration, and invasion in SW1990 and PANC-1 cells. Bioinformatics coupled with luciferase and Western blot assays also revealed that miR-1271 inhibited expression of ZEB1 and TWIST1, which are master regulators of tumor metastasis. Our study first indicates that miR-1271 functions as a suppressor in regulating of pancreatic cancer EMT by targeting ZEB1 and TWIST1, and it promise as a therapeutic target and prognostic marker for metastatic pancreatic cancer. - Highlights: • miR-1271 is downregulated in pancreatic cancer tissues and cell lines. • miR-1271 regulates cell metastasis ability and EMT marker expression. . • miR-1271 directly targets ZEB1 and TWIST1. • ZEB1 and TWIST1 are functionally related to the effects of miR-1271.« less

Tissue transglutaminase regulates focal adhesion kinase/AKT activation by modulating PTEN expression in pancreatic cancer cells.

PubMed

Verma, Amit; Guha, Sushovan; Wang, Huamin; Fok, Jansina Y; Koul, Dimpy; Abbruzzese, James; Mehta, Kapil

2008-04-01

Pancreatic ductal adenocarcinoma (PDAC) progresses rapidly and exhibits profound resistance to treatment. We recently reported that a great majority of PDAC tumors and tumor cell lines express elevated levels of tissue transglutaminase (TG2). Here, we provide first evidence that TG2 expression in PDAC cells results in constitutive activation of focal adhesion kinase/AKT by modulating the expression of the tumor suppressor phosphatase PTEN. Using PDAC cell lines, we determined the effect of TG2 overexpression on PTEN stability and functions. We confirmed the correlation between TG2 expression and PTEN levels in a few (n=51) PDAC tumor samples. We observed that expression of TG2 is inversely correlated with PTEN expression in PDAC cells. Ectopic expression of TG2 inhibited PTEN phosphorylation and promoted its degradation by ubiquitin-proteasomal pathway. Conversely, down-regulation of TG2 by small interfering RNA up-regulated PTEN expression. Clinical relevance of these results was evident in an athymic nude mouse model where down-regulation of endogenous TG2 caused a significant retardation in PDAC xenograft growth. Importantly, the analysis of 51 tumor samples from patients with stage II PDAC revealed that overexpression of TG2 was associated with loss of PTEN expression (P=0.023; odds ratio, 4.1). In multivariate analysis, TG2-mediated loss of PTEN was a prognostic factor for overall survival in patients with stage II pancreatic ductal carcinoma independent of tumor stage/lymph node status and tumor differentiation (P=0.01). TG2 expression in PDAC promotes degradation of PTEN by ubiquitin-proteasomal pathway and results in constitutive activation of focal adhesion kinase/AKT cell survival signaling.

Thy1+IL-7+ lymphatic endothelial cells in iBALT provide a survival niche for memory T-helper cells in allergic airway inflammation

PubMed Central

Shinoda, Kenta; Hirahara, Kiyoshi; Iinuma, Tomohisa; Ichikawa, Tomomi; Suzuki, Akane S.; Sugaya, Kaoru; Tumes, Damon J.; Yamamoto, Heizaburo; Hara, Takahiro; Tani-ichi, Shizue; Ikuta, Koichi; Okamoto, Yoshitaka; Nakayama, Toshinori

2016-01-01

Memory CD4+ T helper (Th) cells are central to long-term protection against pathogens, but they can also be pathogenic and drive chronic inflammatory disorders. How these pathogenic memory Th cells are maintained, particularly at sites of local inflammation, remains unclear. We found that ectopic lymphoid-like structures called inducible bronchus-associated lymphoid tissue (iBALT) are formed during chronic allergic inflammation in the lung, and that memory-type pathogenic Th2 (Tpath2) cells capable of driving allergic inflammation are maintained within the iBALT structures. The maintenance of memory Th2 cells within iBALT is supported by Thy1+IL-7–producing lymphatic endothelial cells (LECs). The Thy1+IL-7–producing LECs express IL-33 and T-cell–attracting chemokines CCL21 and CCL19. Moreover, ectopic lymphoid structures consisting of memory CD4+ T cells and IL-7+IL-33+ LECs were found in nasal polyps of patients with eosinophilic chronic rhinosinusitis. Thus, Thy1+IL-7–producing LECs control chronic allergic airway inflammation by providing a survival niche for memory-type Tpath2 cells. PMID:27140620

Activation of the Hedgehog Signaling Pathway in the Developing Lens Stimulates Ectopic FoxE3 Expression and Disruption in Fiber Cell Differentiation

PubMed Central

Kerr, Christine L.; Huang, Jian; Williams, Trevor; West-Mays, Judith A.

2012-01-01

Purpose. The signaling pathways and transcriptional effectors responsible for directing mammalian lens development provide key regulatory molecules that can inform our understanding of human eye defects. The hedgehog genes encode extracellular signaling proteins responsible for patterning and tissue formation during embryogenesis. Signal transduction of this pathway is mediated through activation of the transmembrane proteins smoothened and patched, stimulating downstream signaling resulting in the activation or repression of hedgehog target genes. Hedgehog signaling is implicated in eye development, and defects in hedgehog signaling components have been shown to result in defects of the retina, iris, and lens. Methods. We assessed the consequences of constitutive hedgehog signaling in the developing mouse lens using Cre-LoxP technology to express the conditional M2 smoothened allele in the embryonic head and lens ectoderm. Results. Although initial lens development appeared normal, morphological defects were apparent by E12.5 and became more significant at later stages of embryogenesis. Altered lens morphology correlated with ectopic expression of FoxE3, which encodes a critical gene required for human and mouse lens development. Later, inappropriate expression of the epithelial marker Pax6, and as well as fiber cell markers c-maf and Prox1 also occurred, indicating a failure of appropriate lens fiber cell differentiation accompanied by altered lens cell proliferation and cell death. Conclusions. Our findings demonstrate that the ectopic activation of downstream effectors of the hedgehog signaling pathway in the mouse lens disrupts normal fiber cell differentiation by a mechanism consistent with a sustained epithelial cellular developmental program driven by FoxE3. PMID:22491411

Hormonal Regulation and Distinct Functions of Semaphorin-3B and Semaphorin-3F in Ovarian Cancer

PubMed Central

Joseph, Doina; Ho, Shuk-Mei; Syed, Viqar

2009-01-01

Semaphorins comprise a family of molecules that influence neuronal growth and guidance. Class-3 semaphorins, semaphorin-3B (SEMA3B) and semaphorin-3F (SEMA3F) illustrate their effects by forming a complex with neuropilins (NP-1 or NP-2) and plexins. We examined the status and regulation of semaphorins and their receptors in human ovarian cancer cells. A significantly reduced expression of SEMA3B (83 kD), SEMA3F (90 kD), and plexin-A3 was observed in ovarian cancer (OVCA) cell lines when compared to normal human ovarian surface epithelial (HOSE) cells. The expression of NP-1, NP-2 and plexin-A1 was not altered in HOSE and OVCA cells. The decreased expression of SEMA3B, SEMA3F, and plexin-A3 was confirmed in stage 3 ovarian tumors. Treatment of OVCA cells with luteinizing hormone, follicle-stimulating hormone, and estrogen induced a significant upregulation of SEMA3B, whereas SEMA3F was upregulated only by estrogen. Co-treatment of cell lines with a hormone and its specific antagonist blocked the effect of the hormone. Ectopic expression of SEMA3B or SEMA3F reduced soft-agar colony formation, adhesion, and cell invasion of OVCA cell cultures. Forced expression of SEMA3B, but not SEMA3F, inhibited viability of OVCA cells. Overexpression of SEMA3B and SEMA3F reduced focal adhesion kinase (FAK) phosphorylation and matrix metalloproteinase (MMP)-2 and -9 expression in OVCA cells. Forced expression of SEMA3F, but not SEMA3B in OVCA cells, significantly inhibited endothelial cell tube formation. Collectively, our results suggest loss of SEMA3 expression could be a hallmark of cancer progression. Furthermore, gonadotropin- and/or estrogen-mediated maintenance of SEMA3 expression could control ovarian cancer angiogenesis and metastasis. PMID:20124444

Prevalence of Ectopic Breast Tissue and Tumor: A 20-Year Single Center Experience.

PubMed

Famá, Fausto; Cicciú, Marco; Sindoni, Alessandro; Scarfó, Paola; Pollicino, Andrea; Giacobbe, Giuseppa; Buccheri, Giancarlo; Taranto, Filippo; Palella, Jessica; Gioffré-Florio, Maria

2016-08-01

Ectopic breast tissue, which includes both supernumerary breast and aberrant breast tissue, is the most common congenital breast abnormality. Ectopic breast cancers are rare neoplasms that occur in 0.3% to 0.6% of all cases of breast cancer. We retrospectively report, using a large series of breast abnormalities diagnosed and treated, our clinical experience on the management of the ectopic breast cancer. In 2 decades, we observed 327 (2.7%) patients with ectopic breast tissue out of a total of 12,177 subjects undergoing a breast visit for lesions. All patients were classified into 8 classes, according to the classification of Kajava, and assessed by a physician examination, ultrasounds, and, when appropriate, further studies with fine needle aspiration cytology and mammography. All specimens were submitted to the anatomo-pathologist. The most frequent benign histological diagnosis was fibrocystic disease. A rare granulosa cell tumor was also found in the right anterior thoracic wall of 1 patient. Four malignancies were also diagnosed in 4 women: an infiltrating lobular cancer in 1 patient with a lesion classified as class I, and an infiltrating apocrine carcinoma, an infiltrating ductal cancer, and an infiltrating ductal cancer with tubular pattern, occurring in 3 patients with lesions classified as class IV. Only 1 recurrence was observed. We recommend an earlier surgical approach for patients with lesions from class I to IV. Copyright © 2016 Elsevier Inc. All rights reserved.

Developmental Role and Auxin Responsiveness of Class III Homeodomain Leucine Zipper Gene Family Members in Rice1[C][W][OA

PubMed Central

Itoh, Jun-Ichi; Hibara, Ken-Ichiro; Sato, Yutaka; Nagato, Yasuo

2008-01-01

Members of the Class III homeodomain leucine zipper (Class III HD-Zip) gene family are central regulators of crucial aspects of plant development. To better understand the roles of five Class III HD-Zip genes in rice (Oryza sativa) development, we investigated their expression patterns, ectopic expression phenotypes, and auxin responsiveness. Four genes, OSHB1 to OSHB4, were expressed in a localized domain of the shoot apical meristem (SAM), the adaxial cells of leaf primordia, the leaf margins, and the xylem tissue of vascular bundles. In contrast, expression of OSHB5 was observed only in phloem tissue. Plants ectopically expressing microRNA166-resistant versions of the OSHB3 gene exhibited severe defects, including the ectopic production of leaf margins, shoots, and radialized leaves. The treatment of seedlings with auxin quickly induced ectopic OSHB3 expression in the entire region of the SAM, but not in other tissues. Furthermore, this ectopic expression of OSHB3 was correlated with leaf initiation defects. Our findings suggest that rice Class III HD-Zip genes have conserved functions with their homologs in Arabidopsis (Arabidopsis thaliana), but have also acquired specific developmental roles in grasses or monocots. In addition, some Class III HD-Zip genes may regulate the leaf initiation process in the SAM in an auxin-dependent manner. PMID:18567825

Ectopic ACTH syndrome caused by pulmonary carcinoid tumourlets.

PubMed

Povedano, S T; Pastor, C V; Seoane, C P; Reina, L J; Moreno, M A; Ortega, R P; López-Rubio, F; López, P B

2001-06-01

The differential diagnosis of Cushing's syndrome is a major challenge to clinical endocrinologists, especially those infrequent cases referred to as occult ectopic ACTH syndromes. Although bronchial carcinoids are well known to be a cause of Cushing's syndrome due to ectopic ACTH secretion, very few cases of carcinoid tumourlets causing an ACTH ectopic syndrome have been reported, and their origin remains controversial. For some authors, tumourlets and typical carcinoids represent distinct pathological entities, whilst others hold that tumourlets are merely microscopic carcinoid tumours. We report a patient with an aggressive Cushing's syndrome that required bilateral adrenalectomy, diagnosed 22 years before a 3-cm lung nodule became apparent on routine chest X-ray. The biopsy after lung surgery revealed a typical peripheral bronchial carcinoid surrounded by tumourlets. Both tumourlets and carcinoid tumour showed strongly positive ACTH immunostaining. Recently, Arioglu et al. (1998) reported a case of Cushing's syndrome caused by pulmonary carcinoid tumourlets, concluding that this entity should be considered in the differential diagnosis of occult ectopic ACTH syndrome. Furthermore, we consider that the carcinoid tumourlets found in our patient, were the initial source of ACTH, leading to Cushing's syndrome with a rapid onset, and that a loss of cell proliferation control in one of such tumourlets many years later, could have resulted in the development of a typical carcinoid tumour, reinforcing the theory of a common origin of these lesions.

Medaka embryonic stem cells are capable of generating entire organs and embryo-like miniatures.

PubMed

Hong, Ni; He, Bei Ping; Schartl, Manfred; Hong, Yunhan

2013-03-01

Embryonic stem (ES) cells have the potency to produce many cell types of the embryo and adult body. Upon transplantation into early host embryos, ES cells are able to differentiate into various specialized cells and contribute to host tissues and organs of all germ layers. Here we present data in the fish medaka (Oryzias latipes) that ES cells have a novel ability to form extra organs and even embryo-like miniatures. Upon transplantation as individual cells according to the standard procedure, ES cells distributed widely to various organ systems of 3 germ layers. Upon transplantation as aggregates, ES cells were able to form extra organs, including the hematopoietic organ and contracting heart. We show that localized ES cell transplantation often led to the formation of extra axes that comprised essentially of either host cells or donor ES cells. These extra axes were associated with the head region of the embryo proper or formed at ectopic sites on the yolk sac. Surprisingly, certain ectopic axes were even capable of forming embryo-like miniatures. We conclude that ES cells have the ability to form entire organs and even embryo-like miniatures under proper environmental conditions. This finding points to a new possibility to generate ES cell-derived axes and organs.

SPARC ectopic overexpression inhibits growth and promotes programmed cell death in acute myeloid leukemia transformed from myelodysplastic syndrome cells, alone and in combination with Ara-C treatment.

PubMed

Nian, Qing; Chi, Jianxiang; Xiao, Qing; Wei, Chunmei; Costeas, Paul; Yang, Zesong; Liu, Lin; Wang, Li

2015-09-01

Secreted protein acidic and rich in cysteine (SPARC) has a complex and pleiotropic biological role in cell life during disease. The role of SPARC in myelodysplastic syndrome (MDS) is not yet fully understood. In the present study, we investigated the role of SPARC protein overproduction in the proliferation and apoptosis of SKM-1 cells, an acute myeloid leukemia cell line transformed from MDS. SKM-1 cells were infected with the pGC-GV-SPARC vector. The cells were then assessed for proliferation and cell death following treatment with low-dose cytosine arabinoside (Ara‑C). The microarray analysis results revealed that samples from SPARC‑overexpressed cells compared to SPARC protein, in SKM-1 cells led to proliferation inhibition and promoted programmed cell death and these effects were greater when treated with Ara-C. The mRNA and protein expression levels of SPARC were detected by SPARC overexpression in cells treated with Ara-C resulting in a significant upregulation of the mixed lineage kinase domain-like (MLKL) gene expression and five other genes. The results showed that the necrotic signaling pathway may play a role when the two conditions were combined via the upregulation of the MLKL protein. MLKL upregulation in SPARC overexpressed cells treated with Ara-C, indicates necrosis as a possible cell death process for the SKM-1 cells under these stringent conditions.

Second branchial cleft anomaly with an ectopic tooth: a case report.

PubMed

Alyono, Jennifer C; Hong, Paul; Page, Nathan C; Malicki, Denise; Bothwell, Marcella R

2014-09-01

Branchial cleft cysts, sinuses, and fistulas are the most common congenital lateral neck lesions in children. They arise as a result of an abnormal development of the branchial arches and their corresponding ectoderm-lined branchial clefts. Of these diverse anomalies, second branchial cleft lesions are the most common, accounting for approximately 95% of all branchial arch pathologies. We describe what is to the best of our knowledge the first reported case of an ectopic tooth in a branchial cleft anomaly. The patient was a young girl who had other congenital abnormalities and syndromic features and who was eventually diagnosed with Townes-Brocks syndrome. We describe the clinical presentation, management, pathologic analysis, and postoperative outcomes of this case, and we present a brief review of Townes-Brocks syndrome.

Traffic jam functions in a branched pathway from Notch activation to niche cell fate.

PubMed

Wingert, Lindsey; DiNardo, Stephen

2015-07-01

The niche directs key behaviors of its resident stem cells, and is thus crucial for tissue maintenance, repair and longevity. However, little is known about the genetic pathways that guide niche specification and development. The male germline stem cell niche in Drosophila houses two stem cell populations and is specified within the embryonic gonad, thus making it an excellent model for studying niche development. The hub cells that form the niche are specified early by Notch activation. Over the next few hours, these individual cells then cluster together and take up a defined position before expressing markers of hub cell differentiation. This timing suggests that there are other factors for niche development yet to be defined. Here, we have identified a role for the large Maf transcription factor Traffic jam (Tj) in hub cell specification downstream of Notch. Tj downregulation is the first detectable effect of Notch activation in hub cells. Furthermore, Tj depletion is sufficient to generate ectopic hub cells that can recruit stem cells. Surprisingly, ectopic niche cells in tj mutants remain dispersed in the absence of Notch activation. This led us to uncover a branched pathway downstream of Notch in which Bowl functions to direct hub cell assembly in parallel to Tj downregulation. © 2015. Published by The Company of Biologists Ltd.

Regulation of early Xenopus development by ErbB signaling

PubMed Central

Nie, Shuyi; Chang, Chenbei

2008-01-01

ErbB signaling has long been implicated in cancer formation and progression and is shown to regulate cell division, migration and death during tumorigenesis. The functions of the ErbB pathway during early vertebrate embryogenesis, however, are not well understood. Here we report characterization of ErbB activities during early frog development. Gain-of-function analyses show that EGFR, ErbB2 and ErbB4 induce ectopic tumor-like cell mass that contains increased numbers of mitotic cells. Both the muscle and the neural markers are expressed in these ectopic protrusions. ErbBs also induce mesodermal markers in ectodermal explants. Loss-of-function studies using carboxyl terminal-truncated dominant-negative ErbB receptors demonstrate that blocking ErbB signals leads to defective gastrulation movements and malformation of the embryonic axis with a reduction in the head structures in early frog embryos. These data, together with the observation that ErbBs are expressed early during frog embryogenesis, suggest that ErbBs regulate cell proliferation, movements and embryonic patterning during early Xenopus development. PMID:16258939

PRC2 Represses Hormone-Induced Somatic Embryogenesis in Vegetative Tissue of Arabidopsis thaliana

PubMed Central

Mozgová, Iva

2017-01-01

Many plant cells can be reprogrammed into a pluripotent state that allows ectopic organ development. Inducing totipotent states to stimulate somatic embryo (SE) development is, however, challenging due to insufficient understanding of molecular barriers that prevent somatic cell dedifferentiation. Here we show that Polycomb repressive complex 2 (PRC2)-activity imposes a barrier to hormone-mediated transcriptional reprogramming towards somatic embryogenesis in vegetative tissue of Arabidopsis thaliana. We identify factors that enable SE development in PRC2-depleted shoot and root tissue and demonstrate that the establishment of embryogenic potential is marked by ectopic co-activation of crucial developmental regulators that specify shoot, root and embryo identity. Using inducible activation of PRC2 in PRC2-depleted cells, we demonstrate that transient reduction of PRC2 activity is sufficient for SE formation. We suggest that modulation of PRC2 activity in plant vegetative tissue combined with targeted activation of developmental pathways will open possibilities for novel approaches to cell reprogramming. PMID:28095419

A rare human syndrome provides genetic evidence that WNT signaling is required for reprogramming of fibroblasts to induced pluripotent stem cells

PubMed Central

Ross, Jason; Busch, Julia; Mintz, Ellen; Ng, Damian; Stanley, Alexandra; Brafman, David; Sutton, V. Reid; Van den Veyver, Ignatia; Willert, Karl

2015-01-01

SUMMARY WNT signaling promotes the reprogramming of somatic cells to an induced pluripotent state. We provide genetic evidence that WNT signaling is a requisite step during the induction of pluripotency. Fibroblasts from individuals with Focal Dermal Hypoplasia (FDH), a rare genetic syndrome caused by mutations in the essential WNT processing enzyme PORCN, fail to reprogram using standard methods. This blockade in reprogramming is overcome by ectopic WNT signaling and by PORCN overexpression, thus demonstrating that WNT signaling is essential for reprogramming. The rescue of reprogramming is critically dependent on the level of WNT signaling: steady baseline activation of the WNT pathway yields karyotypically normal iPS cells, whereas daily stimulation with Wnt3a produces FDH-iPS cells with severely abnormal karyotypes. Therefore, although WNT signaling is required for cellular reprogramming, inappropriate activation of WNT signaling induces chromosomal instability, highlighting the precarious nature of ectopic WNT activation, and its tight relationship with oncogenic transformation. PMID:25464842

Alteration of Nrf2 and Glutamate Cysteine Ligase expression contribute to lesions growth and fibrogenesis in ectopic endometriosis.

PubMed

Marcellin, L; Santulli, P; Chouzenoux, S; Cerles, O; Nicco, C; Dousset, B; Pallardy, M; Kerdine-Römer, S; Just, P A; Chapron, C; Batteux, F

2017-09-01

The redox-sensitive nuclear factor erythroid-derived 2-like 2 (NRF2) controls endogenous antioxidant enzymes' transcription and protects against oxidative damage which is triggered by inflammation and known to favor progression of endometriosis. Glutamate Cysteine Ligase (GCL), a target gene of NRF2, is the first enzyme in the synthesis cascade of glutathione, an important endogenous antioxidant. Sixty-one patients, with thorough surgical examination of the abdominopelvic cavity, were recruited for the study: 31 with histologically-proven endometriosis and 30 disease-free women taken as controls. Expressions of NRF2 and GCL were investigated by quantitative RT-PCR and immunohistochemistry in eutopic and ectopic endometria from endometriosis-affected women and in endometrium of disease-free women. Ex vivo stromal and epithelial cells were extracted and purified from endometrial and endometriotic biopsies to explore expression of NRF2 and GCL in both stromal and epithelial compartments by western blot. Finally, in order to strengthen the role of NRF2 in endometriosis pathogenesis, we evaluated the drop of NRF2 expression in a mouse model of endometriosis using NRF2 knockout (NRF2 -/- ) mice. The mRNA levels of NRF2 and GCL were significantly lower in ectopic endometria of endometriosis-affected women compared to eutopic endometria of disease-free women. The immunohistochemical analysis confirmed the decreased expression of both NRF2 and GCL in ectopic endometriotic tissues compared to eutopic endometria of endometriosis-affected and disease-free women. Immunoblotting revealed a significant decreased of NRF2 and GCL expression in epithelial and stroma cells from ectopic lesions of endometriosis-affected women compared to eutopic endometria from controls. Using a murine model of endometriosis, NRF2 -/- implants were more fibrotic compared to wild-type with an increased weight and volume. These findings indicate that expression of the transcription factor NRF2 and its effector GCL are both profoundly deregulated in endometriotic lesions towards increased growth and fibrogenetic processes. Copyright © 2017 Elsevier Inc. All rights reserved.

NKL homeobox gene activities in hematopoietic stem cells, T-cell development and T-cell leukemia.

PubMed

Nagel, Stefan; Pommerenke, Claudia; Scherr, Michaela; Meyer, Corinna; Kaufmann, Maren; Battmer, Karin; MacLeod, Roderick A F; Drexler, Hans G

2017-01-01

T-cell acute lymphoblastic leukemia (T-ALL) cells represent developmentally arrested T-cell progenitors, subsets of which aberrantly express homeobox genes of the NKL subclass, including TLX1, TLX3, NKX2-1, NKX2-5, NKX3-1 and MSX1. Here, we analyzed the transcriptional landscape of all 48 members of the NKL homeobox gene subclass in CD34+ hematopoietic stem and progenitor cells (HSPCs) and during lymphopoiesis, identifying activities of nine particular genes. Four of these were expressed in HSPCs (HHEX, HLX1, NKX2-3 and NKX3-1) and three in common lymphoid progenitors (HHEX, HLX1 and MSX1). Interestingly, our data indicated downregulation of NKL homeobox gene transcripts in late progenitors and mature T-cells, a phenomenon which might explain the oncogenic impact of this group of genes in T-ALL. Using MSX1-expressing T-ALL cell lines as models, we showed that HHEX activates while HLX1, NKX2-3 and NKX3-1 repress MSX1 transcription, demonstrating the mutual regulation and differential activities of these homeobox genes. Analysis of a public T-ALL expression profiling data set comprising 117 patient samples identified 20 aberrantly activated members of the NKL subclass, extending the number of known NKL homeobox oncogene candidates. While 7/20 genes were also active during hematopoiesis, the remaining 13 showed ectopic expression. Finally, comparative analyses of T-ALL patient and cell line profiling data of NKL-positive and NKL-negative samples indicated absence of shared target genes but instead highlighted deregulation of apoptosis as common oncogenic effect. Taken together, we present a comprehensive survey of NKL homeobox genes in early hematopoiesis, T-cell development and T-ALL, showing that these genes generate an NKL-code for the diverse stages of lymphoid development which might be fundamental for regular differentiation.

NKL homeobox gene activities in hematopoietic stem cells, T-cell development and T-cell leukemia

PubMed Central

Pommerenke, Claudia; Scherr, Michaela; Meyer, Corinna; Kaufmann, Maren; Battmer, Karin; MacLeod, Roderick A. F.; Drexler, Hans G.

2017-01-01

T-cell acute lymphoblastic leukemia (T-ALL) cells represent developmentally arrested T-cell progenitors, subsets of which aberrantly express homeobox genes of the NKL subclass, including TLX1, TLX3, NKX2-1, NKX2-5, NKX3-1 and MSX1. Here, we analyzed the transcriptional landscape of all 48 members of the NKL homeobox gene subclass in CD34+ hematopoietic stem and progenitor cells (HSPCs) and during lymphopoiesis, identifying activities of nine particular genes. Four of these were expressed in HSPCs (HHEX, HLX1, NKX2-3 and NKX3-1) and three in common lymphoid progenitors (HHEX, HLX1 and MSX1). Interestingly, our data indicated downregulation of NKL homeobox gene transcripts in late progenitors and mature T-cells, a phenomenon which might explain the oncogenic impact of this group of genes in T-ALL. Using MSX1-expressing T-ALL cell lines as models, we showed that HHEX activates while HLX1, NKX2-3 and NKX3-1 repress MSX1 transcription, demonstrating the mutual regulation and differential activities of these homeobox genes. Analysis of a public T-ALL expression profiling data set comprising 117 patient samples identified 20 aberrantly activated members of the NKL subclass, extending the number of known NKL homeobox oncogene candidates. While 7/20 genes were also active during hematopoiesis, the remaining 13 showed ectopic expression. Finally, comparative analyses of T-ALL patient and cell line profiling data of NKL-positive and NKL-negative samples indicated absence of shared target genes but instead highlighted deregulation of apoptosis as common oncogenic effect. Taken together, we present a comprehensive survey of NKL homeobox genes in early hematopoiesis, T-cell development and T-ALL, showing that these genes generate an NKL-code for the diverse stages of lymphoid development which might be fundamental for regular differentiation. PMID:28151996

Tissue integrity is essential for ectopic implantation of human endometrium in the chicken chorioallantoic membrane.

PubMed

Nap, Annemiek W; Groothuis, Patrick G; Demir, Ayse Y; Maas, Jacques W M; Dunselman, Gerard A J; de Goeij, Anton F P M; Evers, Johannes L H

2003-01-01

Not all women with patent tubes develop clinically manifest endometriosis. Quality and quantity of endometrium in retrograde menstruation may be the determining factor in the development of the disease. We hypothesize that retrograde shedding of endometrial fragments with preserved integrity facilitates implantation of endometrium in ectopic locations, resulting in endometriotic lesion development. We evaluate the impact of tissue integrity on the success of endometriosis-like lesion development in the chicken embryo chorioallantoic membrane (CAM) model. Menstrual and non-menstrual (cyclic) endometrium were collected by biopsy, and either minced or enzymatically dispersed. Spontaneously shed menstrual effluent was collected by a menstrual cup, and cells and tissue were isolated. We evaluated whether infiltration or lesion formation in the CAM occurred after transplantation of endometrium onto the CAM. Transplantation of biopsied menstrual and cyclic endometrium fragments, and of endometrium fragments >1 mm(3) isolated from menstrual effluent, resulted in lesion formation. Transplantation of endometrial cells isolated from menstrual effluent did not lead to lesion formation. After transplantation of digested biopsied cyclic endometrium, infiltration in the CAM but no lesions were observed. In the CAM assay, integrity of tissue architecture determines success of implantation of human endometrium in ectopic locations.

Ectopic expression of the gastric inhibitory polypeptide receptor gene is a sufficient genetic event to induce benign adrenocortical tumor in a xenotransplantation model.

PubMed

Mazzuco, Tania L; Chabre, Olivier; Sturm, Nathalie; Feige, Jean-Jacques; Thomas, Michaël

2006-02-01

Aberrant expression of ectopic G protein-coupled receptors (GPCRs) in adrenal cortex tissue has been observed in several cases of ACTH-independent macronodular adrenal hyperplasias and adenomas associated with Cushing's syndrome. Although there is clear clinical evidence for the implication of these ectopic receptors in abnormal regulation of cortisol production, whether this aberrant GPCR expression is the cause or the consequence of the development of an adrenal hyperplasia is still an open question. To answer it, we genetically engineered primary bovine adrenocortical cells to have them express the gastric inhibitory polypeptide receptor. After transplantation of these modified cells under the renal capsule of adrenalectomized immunodeficient mice, tissues formed had their functional and histological characteristics analyzed. We observed the formation of an enlarged and hyperproliferative adenomatous adrenocortical tissue that secreted cortisol in a gastric inhibitory polypeptide-dependent manner and induced a mild Cushing's syndrome with hyperglycemia. Moreover, we show that tumor development was ACTH independent. Thus, a single genetic event, inappropriate expression of a nonmutated GPCR gene, is sufficient to initiate the complete phenotypic alterations that ultimately lead to the formation of a benign adrenocortical tumor.

Elevated ATF4 Expression, in the Absence of Other Signals, Is Sufficient for Transcriptional Induction via CCAAT Enhancer-binding Protein-activating Transcription Factor Response Elements*

PubMed Central

Shan, Jixiu; Örd, Daima; Örd, Tõnis; Kilberg, Michael S.

2009-01-01

Protein limitation in vivo or amino acid deprivation of cells in culture causes a signal transduction cascade consisting of activation of the kinase GCN2 (general control nonderepressible 2), phosphorylation of eukaryotic initiation factor 2, and increased synthesis of activating transcription factor (ATF) 4 by a translational control mechanism. In a self-limiting transcriptional program, ATF4 transiently activates a wide range of downstream target genes involved in transport, cellular metabolism, and other cell functions. Simultaneous activation of other signal transduction pathways by amino acid deprivation led to the question of whether or not the increased abundance of ATF4 alone was sufficient to trigger the transcriptional control mechanisms. Using 293 cells that ectopically express ATF4 in a tetracycline-inducible manner showed that ATF4 target genes were activated in the absence of amino acid deprivation. Ectopic expression of ATF4 alone resulted in effective recruitment of the general transcription machinery, but some reduction in histone modification was observed. These data document that ATF4 alone is sufficient to trigger the amino acid-responsive transcriptional control program. However, the absolute amount of ectopic ATF4 required to achieve the same degree of transcriptional activation observed after amino acid limitation was greater, suggesting that other factors may serve to enhance ATF4 function. PMID:19509279

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

Zhong, Yiming; Program in Molecular, Cellular, and Developmental Biology, The Ohio State University, Columbus, OH; Sullenbarger, Brent

Research highlights: {yields} HoxB4 overexpression in human TF1 cells increased the expression of CD61 and CD41a. {yields} HoxB4 fusion protein enhanced megakaryocytic development of CD34{sup +} cord blood cells. {yields} Ectopic HoxB4 increased Tpo receptor expression and decreased c-Myb expression. {yields} HoxB4 RNA silencing increased c-Myb expression and decreased Fli-1 expression. -- Abstract: In order to produce clinically useful quantities of platelets ex vivo we may need to firstly enhance early self-renewal of hematopoietic stem cells (HSCs) and/or megakaryocyte (Mk) progenitors. The homeodomain transcription factor HoxB4 has been shown to be an important regulator of stem cell renewal and hematopoiesis;more » however, its effect on megakaryopoiesis is unclear. In this study, we investigated the effect of HoxB4 overexpression or RNA silencing on megakaryocytic development in the human TF1 progenitor cell line; we then used recombinant tPTD-HoxB4 fusion protein to study the effect of exogenous HoxB4 on megakaryocytic development of human CD34 positively-selected cord blood cells. We found that ectopic HoxB4 in TF1 cells increased the antigen expression of CD61and CD41a, increased the gene expression of thrombopoietin receptor (TpoR), Scl-1, Cyclin D1, Fog-1 and Fli-1 while it decreased c-Myb expression. HoxB4 RNA silencing in TF1 cells decreased the expression of CD61 and CD41a and decreased Fli-1 expression while it increased the expression of c-Myb. Recombinant tPTD-HoxB4 fusion protein increased the percentages and absolute numbers of CD41a and CD61 positive cells during megakaryocytic differentiation of CD34 positively-selected cord blood cells and increased the numbers of colony-forming unit-megakaryocyte (CFU-Mk). Adding tPTD-HoxB4 fusion protein increased the gene expression of TpoR, Cyclin D1, Fog-1 and Fli-1 while it inhibited c-Myb expression. Our data suggest that increased HoxB4 enhanced early megakaryocytic development in human TF1 cells and CD34 positively-selected cord blood cells primarily by upregulating TpoR and Fli-1 expression and downregulating c-Myb expression. Increasing HoxB4 expression or adding recombinant HoxB4 protein might be a way to expand Mks for the production of platelets for use in transfusion medicine.« less

Enhanced growth of influenza A virus by coinfection with human parainfluenza virus type 2.

PubMed

Goto, Hideo; Ihira, Hironobu; Morishita, Keiichi; Tsuchiya, Mitsuki; Ohta, Keisuke; Yumine, Natsuko; Tsurudome, Masato; Nishio, Machiko

2016-06-01

It has been reported that dual or multiple viruses can coinfect epithelial cells of the respiratory tract. However, little has been reported on in vitro interactions of coinfected viruses. To explore how coinfection of different viruses affects their biological property, we examined growth of influenza A virus (IAV) and human parainfluenza virus type 2 (hPIV2) during coinfection of Vero cells. We found that IAV growth was enhanced by coinfection with hPIV2. The enhanced growth of IAV was not reproduced by coinfection with an hPIV2 mutant with reduced cell fusion activity, or by ectopic expression of the V protein of hPIV2. In contrast, induction of cell fusion by ectopic expression of the hPIV2 HN and F proteins augments IAV growth. hPIV2 coinfection supported IAV growth in cells originated from the respiratory epithelium. The enhancement correlated closely with cell fusion ability of hPIV2 in those cells. These results indicate that cell fusion induced by hPIV2 infection is beneficial to IAV replication and that enhanced viral replication by coinfection with different viruses can modify their pathological consequences.

Accessing naïve human pluripotency

PubMed Central

De Los Angeles, Alejandro; Loh, Yuin-Han; Tesar, Paul J; Daley, George Q

2014-01-01

Pluripotency manifests during mammalian development through formation of the epiblast, founder tissue of the embryo proper. Rodent pluripotent stem cells can be considered as two distinct states: naïve and primed. Naïve pluripotent stem cell lines are distinguished from primed cells by self-renewal in response to LIF signaling and MEK/GSK3 inhibition (LIF/2i conditions) and two active X chromosomes in female cells. In rodent cells, the naïve pluripotent state may be accessed through at least three routes: explantation of the inner cell mass, somatic cell reprogramming by ectopic Oct4, Sox2, Klf4, and C-myc, and direct reversion of primed post-implantation-associated epiblast stem cells (EpiSCs). In contrast to their rodent counterparts, human embryonic stem cells and induced pluripotent stem cells more closely resemble rodent primed EpiSCs. A critical question is whether naïve human pluripotent stem cells with bona fide features of both a pluripotent state and naïve-specific features can be obtained. In this review, we outline current understanding of the differences between these pluripotent states in mice, new perspectives on the origins of naïve pluripotency in rodents, and recent attempts to apply the rodent paradigm to capture naïve pluripotency in human cells. Unraveling how to stably induce naïve pluripotency in human cells will influence the full realization of human pluripotent stem cell biology and medicine. PMID:22463982

An endogenous and ectopic expression of metabotropic glutamate receptor 8 (mGluR8) inhibits proliferation and increases chemosensitivity of human neuroblastoma and glioma cells.

PubMed

Jantas, Danuta; Grygier, Beata; Gołda, Sławomir; Chwastek, Jakub; Zatorska, Justyna; Tertil, Magdalena

2018-06-06

The present study aimed to determine the role of metabotropic glutamate receptor 8 (mGluR8) in tumor biology. Using various molecular approaches (RNAi or GRM8 cDNA), cell clones with downregulated (human neuroblastoma SH-SY5Y and human glioma LN229) or overexpressed (human glioma U87-MG and LN18 cell lines) mGluR8 were generated. Next, comparative studies on cell proliferation and migration rates, induction of apoptosis and chemosensitivity were performed among these clones. The mGluR8-downregulated SH-SY5Y clones proliferated faster and were more resistant to cytotoxic action of staurosporine, doxorubicin, irinotecan and cisplatin when compared to control cells. Moreover, these clones were characterized by a lower activity of caspases, calpains and some kinases (GSK-3β, Akt and JNK). The mGluR8-downregulated LN229 clones migrated faster and were less prone to cell-damaging effect of staurosporine and irinotecan when compared with relevant control cells. In contrast, in GRM8-overexpressing U87-MG and LN18 clones, a decreased cell proliferation, increased apoptosis and elevated vulnerability to some cytotoxic agents were found. Altogether, our in vitro data for the first time evidenced a tumor suppressor and chemosensitizing role of mGluR8. Copyright © 2018 Elsevier B.V. All rights reserved.

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

PubMed Central

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

2013-01-01

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

Over-accumulation of nuclear IGF-1 receptor in tumor cells requires elevated expression of the receptor and the SUMO-conjugating enzyme Ubc9

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

Deng, Hua; Lin, Yingbo; Badin, Margherita

2011-01-14

Research highlights: {yields} SUMOylation mediates nuclear translocation of IGF-1R which activates transcription. {yields} Here we show that nuclear IGF-1R over-accumulates in tumor cells. {yields} This requires overexpression of the receptor that is a common feature in tumor cells. {yields} An increased expression of the SUMO ligase Ubc9 seems to be an involved mechanism too. -- Abstract: The insulin-like growth factor 1 receptor (IGF-1R) plays crucial roles in tumor cell growth and is overexpressed in many cancers. IGF-1R's trans-membrane kinase signaling pathways have been well characterized. Very recently, we showed that SUMOylation mediates nuclear translocation of the IGF-1R, and that nuclearmore » IGF-1R (nIGF-1R) binds to enhancer regions and activates transcription. We identified three lysine residues in the {beta}-subunit of the receptor and that mutation of these blocks nuclear translocation and gene activation. Furthermore, accumulation of nIGF-1R was proven strongly dependent on the specific SUMO-conjugating enzyme Ubc9. Here we show that nIGF-1R originates solely from the cell membrane and that phosphorylation of the core tyrosine residues of the receptor kinase is crucial for nuclear accumulation. We also compared the levels of nIGF-1R, measured as nuclear/membrane ratios, in tumor and normal cells. We found that the breast cancer cell line MCF-7 has 13-fold higher amounts of nIGF-1R than breast epithelial cells (IME) which showed only a small amount of nIGF-1R. In comparison, the total expression of IGF-1R was only 3.7- higher in MCF-7. Comparison of several other tumor and normal cell lines showed similar tumor cell over-accumulation of nIGF-1R, exceeding the total receptor expression substantially. Ectopic overexpression (>10-fold) of the receptor increased nIGF-1R in IME cells but not to that high level as in wild type MCF-7. The levels of Ubc9 were higher in all tumor cell lines, compared to the normal cells, and this probably contributes to over-accumulation of nIGF-1R. Over-accumulation of nIGF-1R may contribute to deregulated gene expression and therewith play a pathophysiological role in cancer cells.« less

Phosphatidylserine recognition and induction of apoptotic cell clearance by Drosophila engulfment receptor Draper.

PubMed

Tung, Tran Thanh; Nagaosa, Kaz; Fujita, Yu; Kita, Asana; Mori, Hiroki; Okada, Ryo; Nonaka, Saori; Nakanishi, Yoshinobu

2013-05-01

The membrane phospholipid phosphatidylserine is exposed on the cell surface during apoptosis and acts as an eat-me signal in the phagocytosis of apoptotic cells in mammals and nematodes. However, whether this is also true in insects was unclear. When milk fat globule-epidermal growth factor 8, a phosphatidylserine-binding protein of mammals, was ectopically expressed in Drosophila, the level of phagocytosis was reduced, whereas this was not the case for the same protein lacking a domain responsible for the binding to phosphatidylserine. We found that the extracellular region of Draper, an engulfment receptor of Drosophila, binds to phosphatidylserine in an enzyme-linked immunosorbent assay-like solid-phase assay and in an assay for surface plasmon resonance. A portion of Draper containing domains EMI and NIM located close to the N-terminus was required for binding to phosphatidylserine, and a Draper protein lacking this region was not active in Drosophila. Finally, the level of tyrosine-phosphorylated Draper, indicative of the activation of Draper, in a hemocyte-derived cell line was increased after treatment with phosphatidylserine-containing liposome. These results indicated that phosphatidylserine serves as an eat-me signal in the phagocytic removal of apoptotic cells in Drosophila and that Draper is a phosphatidylserine-binding receptor for phagocytosis.

Functional activation of mutant p53V172F by platinum analogs in cisplatin-resistant human tumor cells is dependent on serine-20 phosphorylation

PubMed Central

Xie, Xiaolei; He, Guangan; Siddik, Zahid H.

2017-01-01

Dysfunctionality of the p53 tumor suppressor is a major cause of therapeutic drug resistance in cancer. Recently we reported that mutant, but otherwise functional, p53V172F was inactivated in cisplatin-resistant 2780CP/Cl-16 and 2780CP/Cl-24 human ovarian tumor cells by increased recruitment of the inhibitor MDM4. The current study demonstrates that, unlike cisplatin, platinum analogs oxaliplatin and DACH-diacetato-dichloro-Pt(IV) (DAP), strongly stabilize and activate p53V172F in resistant cells, as indicated by prolonged p53 half-life and transactivation of targets p21 (CDKN1A) and MDM2. This increase in MDM2 reduced MDM4 levels in cell lysates as well as the p53 immunocomplex and prevented reversion of p53 to the inactive p53-MDM2-MDM4 bound state. Phosphorylation of p53 at Ser15 was demonstrated by all three drugs in sensitive A2780 and corresponding resistant 2780CP/Cl-16 and 2780CP/Cl-24 cell lines. However, cisplatin induced Ser20 phosphorylation in A2780 cells only, but not in resistant cells; in contrast, both DAP and oxaliplatin induced this phosphorylation in all three cell lines. The inference that Ser20 phosphorylation is more important for p53 activation was confirmed by ectopic expression of a phosphomimetic (S20D) mutant p53 that displayed reduced binding, relative to wild-type p53, to both MDM2 and MDM4 in p53-knockout A2780 cells. In consonance, temporal studies demonstrated drug-induced Ser15 phosphorylation coincided with p53 stabilization, whereas Ser20 phosphorylation coincided with p53 transactivation. Implications Cisplatin fails to activate the pathway involved in phosphorylating mutant p53V172F at Ser20 in resistant cells, but this phosphorylation is restored by oxaliplatin and DAP that reactivates p53 function and circumvents cisplatin resistance. PMID:28031409

The 3p14.2 tumour suppressor ADAMTS9 is inactivated by promoter CpG methylation and inhibits tumour cell growth in breast cancer.

PubMed

Shao, Bianfei; Feng, Yixiao; Zhang, Hongbin; Yu, Fang; Li, Qianqian; Tan, Cui; Xu, Hongying; Ying, Jianming; Li, Lili; Yang, Dejuan; Peng, Weiyan; Tang, Jun; Li, Shuman; Ren, Guosheng; Tao, Qian; Xiang, Tingxiu

2018-02-01

Chromosome region 3p12-14 is an important tumour suppressor gene (TSG) locus for multiple cancers. ADAMTS9, a member of the metalloprotease large family, has been identified as a candidate 3p14.2 TSG inactivated by aberrant promoter CpG methylation in several carcinomas, but little known about its expression and function in breast cancer. In this report, ADAMTS9 expression and methylation was analysed in breast cancer cell lines and tissue samples. ADAMTS9 RNA was significantly down-regulated in breast cancer cell lines (6/8). After treating the cells with demethylation agent Aza and TSA, ADAMTS9 expression was dramatically increased. Bisulphite genomic sequencing and methylation-specific PCR detected promoter methylation, which was associated with decreased ADAMTS9 expression. Hypermethylation was also detected in 130/219 (59.4%) of primary tumours but only in 4.5% (2/44) of paired surgical margin tissues. Ectopic expression of ADAMTS9 in tumor cells induced significant growth suppression, cell cycle arrest at the G0/G1 phase, enhanced apoptosis and reduced cell migration and invasion. Conditioned culture medium from ADAMTS9-transfected BT549 cells markedly disrupted tube formation ability of human umbilical vein endothelial cell (HUVEC) in Matrigel. Furthermore, ADAMTS9 inhibited AKT signaling and its downstream targets (MDM2, p53, p21, p27, E-cadherin, VIM, SNAIL, VEGFA, NFκB-p65 and MMP2). In addition, we demonstrated, for the first time, that ADAMTS9 inhibits AKT signaling, through suppressing its upstream activators EGFR and TGFβ1/TβR(I/II) in breast cancer cells. Our results suggest that ADAMTS9 is a TSG epigenetically inactivated in breast cancer, which functions through blocking EGFR- and TGFβ1/TβR(I/II)-activated AKT signaling. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Long non-coding RNA BRAF-regulated lncRNA 1 promotes lymph node invasion, metastasis and proliferation, and predicts poor prognosis in breast cancer.

PubMed

Jiang, Jing; Shi, Sheng-Hong; Li, Xu-Jun; Sun, Long; Ge, Qi-Dong; Li, Chao; Zhang, Wei

2018-06-01

Long non-coding RNAs (lncRNAs) are primary regulators of cancer development via their involvement in almost every aspect of cell biology. Recent studies have indicated that lncRNAs serve pivotal roles in breast cancer (BC) progression; however, to the best of our knowledge, the role of the lncRNA BRAF-regulated lncRNA 1 (BANCR) in BC has not yet been elucidated. The present study revealed that BANCR was overexpressed in BC cell lines and tissues, and could promote the clinical progression of disease, including increases in tumor size, lymph node metastasis and Tumor-Node-Metastasis stage. Furthermore, high BANCR expression was demonstrated to be associated with poor overall survival rates and early recurrence of BC in patients. Additionally, univariate and multivariate COX regression analyses identified high BANCR expression as an independent risk factor of poor prognosis of patients with BC. In addition, to verify the function of BANCR in BC cell lines, BANCR expression was silenced using short hairpin RNAs in MDA-MB-231 cells and overexpressed in MDA-MB-468 cells. An MTT assay and colony formation assay indicated that BANCR knockdown could suppress the proliferation of BC cells, whereas BANCR upregulation induced the proliferation of BC cells. Furthermore, BANCR silencing also reduced the migration and invasion of BC cells, as demonstrated via transwell migration and invasion assays. Consistently, the migration and invasion of BC cells increased upon BANCR ectopic overexpression in MDA-MB-468 cells. Mechanistically, matrix metallopeptidase 2/9 and epithelial-mesenchymal transition markers may be the potential targets of BANCR in regulating BC metastasis. In conclusion, BANCR overexpression could promote the clinical progression, metastasis and proliferation of BC and indicate poor prognosis of patients with BC. BANCR may therefore be a potential prognostic marker and therapeutic target of patients with BC.

Senseless, a Zn finger transcription factor, is necessary and sufficient for sensory organ development in Drosophila

NASA Technical Reports Server (NTRS)

Nolo, R.; Abbott, L. A.; Bellen, H. J.

2000-01-01

The senseless (sens) gene is required for proper development of most cell types of the embryonic and adult peripheral nervous system (PNS) of Drosophila. Sens is a nuclear protein with four Zn fingers that is expressed and required in the sensory organ precursors (SOP) for proper proneural gene expression. Ectopic expression of Sens in many ectodermal cells causes induction of PNS external sensory organ formation and is able to recreate an ectopic proneural field. Hence, sens is both necessary and sufficient for PNS development. Our data indicate that proneural genes activate sens expression. Sens is then in turn required to further activate and maintain proneural gene expression. This feedback mechanism is essential for selective enhancement and maintenance of proneural gene expression in the SOPs.

The bHLH Repressor Deadpan Regulates the Self-renewal and Specification of Drosophila Larval Neural Stem Cells Independently of Notch

PubMed Central

Younger, Susan; Huang, Yaling; Lee, Tzumin

2012-01-01

Neural stem cells (NSCs) are able to self-renew while giving rise to neurons and glia that comprise a functional nervous system. However, how NSC self-renewal is maintained is not well understood. Using the Drosophila larval NSCs called neuroblasts (NBs) as a model, we demonstrate that the Hairy and Enhancer-of-Split (Hes) family protein Deadpan (Dpn) plays important roles in NB self-renewal and specification. The loss of Dpn leads to the premature loss of NBs and truncated NB lineages, a process likely mediated by the homeobox protein Prospero (Pros). Conversely, ectopic/over-expression of Dpn promotes ectopic self-renewing divisions and maintains NB self-renewal into adulthood. In type II NBs, which generate transit amplifying intermediate neural progenitors (INPs) like mammalian NSCs, the loss of Dpn results in ectopic expression of type I NB markers Asense (Ase) and Pros before these type II NBs are lost at early larval stages. Our results also show that knockdown of Notch leads to ectopic Ase expression in type II NBs and the premature loss of type II NBs. Significantly, dpn expression is unchanged in these transformed NBs. Furthermore, the loss of Dpn does not inhibit the over-proliferation of type II NBs and immature INPs caused by over-expression of activated Notch. Our data suggest that Dpn plays important roles in maintaining NB self-renewal and specification of type II NBs in larval brains and that Dpn and Notch function independently in regulating type II NB proliferation and specification. PMID:23056424

Germ-Line Recombination Activity of the Widely Used hGFAP-Cre and Nestin-Cre Transgenes

PubMed Central

Zhang, Jiong; Dublin, Pavel; Griemsmann, Stephanie; Klein, Alexandra; Brehm, Ralph; Bedner, Peter; Fleischmann, Bernd K.; Steinhäuser, Christian; Theis, Martin

2013-01-01

Herein we demonstrate with PCR, immunodetection and reporter gene approaches that the widely used human Glial Fibrillary Acidic Protein (hGFAP)-Cre transgene exhibits spontaneous germ-line recombination activity in leading to deletion in brain, heart and tail tissue with high frequency. The ectopic activity of hGFAP-Cre requires a rigorous control. We likewise observed that a second widely used nestin-Cre transgene shows germ-line deletion. Here we describe procedures to identify mice with germ-line recombination mediated by the hGFAP-Cre and nestin-Cre transgenes. Such control is essential to avoid pleiotropic effects due to germ-line deletion of loxP-flanked target genes and to maintain the CNS-restricted deletion status in transgenic mouse colonies. PMID:24349371

Ectopic Kidney

MedlinePlus

... Ectopic Kidney Medullary Sponge Kidney Kidney Dysplasia Ectopic Kidney What is an ectopic kidney? An ectopic kidney is a birth defect in ... has an ectopic kidney. 1 What are the kidneys and what do they do? The kidneys are ...

Multiethnic genome-wide meta-analysis of ectopic fat depots identifies loci associated with adipocyte development and differentiation.

PubMed

Chu, Audrey Y; Deng, Xuan; Fisher, Virginia A; Drong, Alexander; Zhang, Yang; Feitosa, Mary F; Liu, Ching-Ti; Weeks, Olivia; Choh, Audrey C; Duan, Qing; Dyer, Thomas D; Eicher, John D; Guo, Xiuqing; Heard-Costa, Nancy L; Kacprowski, Tim; Kent, Jack W; Lange, Leslie A; Liu, Xinggang; Lohman, Kurt; Lu, Lingyi; Mahajan, Anubha; O'Connell, Jeffrey R; Parihar, Ankita; Peralta, Juan M; Smith, Albert V; Zhang, Yi; Homuth, Georg; Kissebah, Ahmed H; Kullberg, Joel; Laqua, René; Launer, Lenore J; Nauck, Matthias; Olivier, Michael; Peyser, Patricia A; Terry, James G; Wojczynski, Mary K; Yao, Jie; Bielak, Lawrence F; Blangero, John; Borecki, Ingrid B; Bowden, Donald W; Carr, John Jeffrey; Czerwinski, Stefan A; Ding, Jingzhong; Friedrich, Nele; Gudnason, Vilmunder; Harris, Tamara B; Ingelsson, Erik; Johnson, Andrew D; Kardia, Sharon L R; Langefeld, Carl D; Lind, Lars; Liu, Yongmei; Mitchell, Braxton D; Morris, Andrew P; Mosley, Thomas H; Rotter, Jerome I; Shuldiner, Alan R; Towne, Bradford; Völzke, Henry; Wallaschofski, Henri; Wilson, James G; Allison, Matthew; Lindgren, Cecilia M; Goessling, Wolfram; Cupples, L Adrienne; Steinhauser, Matthew L; Fox, Caroline S

2017-01-01

Variation in body fat distribution contributes to the metabolic sequelae of obesity. The genetic determinants of body fat distribution are poorly understood. The goal of this study was to gain new insights into the underlying genetics of body fat distribution by conducting sample-size-weighted fixed-effects genome-wide association meta-analyses in up to 9,594 women and 8,738 men of European, African, Hispanic and Chinese ancestry, with and without sex stratification, for six traits associated with ectopic fat (hereinafter referred to as ectopic-fat traits). In total, we identified seven new loci associated with ectopic-fat traits (ATXN1, UBE2E2, EBF1, RREB1, GSDMB, GRAMD3 and ENSA; P < 5 × 10 -8 ; false discovery rate < 1%). Functional analysis of these genes showed that loss of function of either Atxn1 or Ube2e2 in primary mouse adipose progenitor cells impaired adipocyte differentiation, suggesting physiological roles for ATXN1 and UBE2E2 in adipogenesis. Future studies are necessary to further explore the mechanisms by which these genes affect adipocyte biology and how their perturbations contribute to systemic metabolic disease.

Id-1 promotes osteosarcoma cell growth and inhibits cell apoptosis via PI3K/AKT signaling pathway

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

Hao, Liang; Liao, Qi; Tang, Qiang

2016-02-12

Accumulating evidence reveals that Id-1 is upregulated and functions as a potential tumor promoter in several human cancer types. However, the role of Id-1 in osteosarcoma (OS) is unknown. In present study, we found that Id-1 expression was elevated in OS tissues than adjacent normal bone tissues. More importantly, we demonstrated that overexpression of Id-1 is significantly correlated with tumor progression and poor survival in OS patients. Furthermore, increased expression of Id-1 was observed in OS cell lines and ectopic expression of Id-1 significantly enhanced in vitro cell proliferation and promoted in vivo tumor growth, whereas knockdown of Id-1 suppressed OS cellsmore » growth. Moreover, our experimental data revealed that Id-1 promotes cell proliferation by facilitating cell cycle progression and inhibits cell apoptosis. Mechanistically, the effects of Id-1 in OS cells is at least partly through activation of PI3K/Akt signaling pathway. Therefore, we identified a tumorigenic role of Id-1 in OS and suggested a potential therapeutic target for OS patients. - Highlights: • Id-1 expression is positively correlated in OS patients with poor prognosis. • Overexpression of Id-1 promotes OS cell growth in vitro and in vivo. • Id-1induces cell cycle progression and inhibits cell apoptosis. • PI3K/Akt signaling pathway contributed to the oncogenic effects of Id-1 in OS cells.« less

Loss of Dickkopf 3 Promotes the Tumorigenesis of Basal Breast Cancer

PubMed Central

Lorsy, Eva; Topuz, Aylin Sophie; Geisler, Cordelia; Stahl, Sarah; Garczyk, Stefan; von Stillfried, Saskia; Hoss, Mareike; Gluz, Oleg; Hartmann, Arndt; Knüchel, Ruth; Dahl, Edgar

2016-01-01

Dickkopf 3 (DKK3) has been associated with tumor suppression of various tumor entities including breast cancer. However, the functional impact of DKK3 on the tumorigenesis of distinct molecular breast cancer subtypes has not been considered so far. Therefore, we initiated a study analyzing the subtype-specific DKK3 expression pattern as well as its prognostic and functional impact with respect to breast cancer subtypes. Based on three independent tissue cohorts including one in silico dataset (n = 30, n = 463 and n = 791) we observed a clear down-regulation of DKK3 expression in breast cancer samples compared to healthy breast tissue controls on mRNA and protein level. Interestingly, most abundant reduction of DKK3 expression was detected in the highly aggressive basal breast cancer subtype. Analyzing a large in silico dataset comprising 3,554 cases showed that low DKK3 mRNA expression was significantly associated with reduced recurrence free survival (RFS) of luminal and basal-like breast cancer cases. Functionally, DKK3 re-expression in human breast cancer cell lines led to suppression of cell growth possibly mediated by up-regulation of apoptosis in basal-like but not in luminal-like breast cancer cell lines. Moreover, ectopic DKK3 expression in mesenchymal basal breast cancer cells resulted in partial restoration of epithelial cell morphology which was molecularly supported by higher expression of epithelial markers like E-Cadherin and down-regulation of mesenchymal markers such as Snail 1. Hence, we provide evidence that down-regulation of DKK3 especially promotes tumorigenesis of the aggressive basal breast cancer subtype. Further studies decoding the underlying molecular mechanisms of DKK3-mediated effects may help to identify novel targeted therapies for this clinically highly relevant breast cancer subtype. PMID:27467270

Induction of E-cadherin in lung cancer and interaction with growth suppression by histone deacetylase inhibition.

PubMed

Kakihana, Masatoshi; Ohira, Tatsuo; Chan, Daniel; Webster, Robin B; Kato, Harubumi; Drabkin, Harry A; Gemmill, Robert M

2009-12-01

Loss of E-cadherin confers a poor prognosis in lung cancer patients and is associated with in vitro resistance to endothelial growth factor receptor inhibitors. Zinc finger E box-binding homeobox (ZEB)-1, the predominant transcriptional suppressor of E-cadherin in lung tumor lines, recruits histone deacetylases (HDACs) as co-repressors. NSCLC cell lines were treated with HDAC inhibitors and analyzed for E-cadherin induction, growth inhibition and apoptosis. National Cancer Institute-H157 cells expressing ectopic E-cadherin were tested for tumorigenicity in murine xenografts. We found that treatment with MS-275, compared to vorinostat (SAHA), valproic acid or trichostatin A, was most effective in E-cadherin up-regulation and persistence in non-small cell lung cancers. As with other tumor types and HDAC inhibitors, MS-275 inhibited growth and induced apoptosis. Importantly, blocking E-cadherin induction by short hairpin RNA resulted in less inhibition by MS-275, implicating the epithelial to mesenchymal phenotype process as a contributing factor. In contrast to H460 and H661, H157 cells were resistant to E-cadherin up-regulation by HDAC inhibitors. However, E-cadherin was restored, in a synergistic manner, by combined knockdown of ZEB-1 and ZEB-2. In addition, H157 cells stably transfected with E-cadherin were markedly attenuated in their tumor forming ability. Lastly, combining MS-275 with the microtubule stabilizing agent, paclitaxel, or 17-(allylamino)-17-demethoxygeldanamycin, a heat shock protein 90 inhibitor, resulted in synergistic growth inhibition. Since MS-275 has no reported activity against HDAC6, which regulates both microtubule and heat shock protein 90 functions, other mechanisms of synergy are anticipated. These results support the role of ZEB proteins and HDAC inhibitors in the pathogenesis and treatment of lung cancer.

Expression of β-catenin protein in hepatocellular carcinoma and its relationship with alpha-fetoprotein.

PubMed

Ren, Ya-Jun; Huang, Tao; Yu, Hong-Lu; Zhang, Li; He, Qian-Jin; Xiong, Zhi-Fan; Peng, Hua

2016-12-01

This study aimed to investigate the expression of β-catenin in hepatocellular carcinoma (HCC) tissues and its relationship with α-fetoprotein (AFP) in HCC. Immunohistochemistry was used to determine the expression of β-catenin in normal liver tissues (n=10), liver cirrhosis tissues (n=20), and primary HCC tissues (n=60). The relationship between β-catenin expression and clinical parameters of HCC was investigated. Real-time PCR and Western blotting were used to detect the mRNA and protein expression levels of β-catenin in the liver cancer cell line SMMC-7721 transfected with a plasmid encoding AFP, and also the mRNA and protein expression levels of β-catenin were measured in the liver cancer cell line Huh7 before and after the transfection with AFP shRNA plasmids. The results showed that β-catenin was only expressed on the cell membrane in normal liver tissues. Its localization to the cytoplasm and nucleus of cells was observed in a small proportion of cirrhotic tissues or adjacent HCC tissues, and such ectopic expression of β-catenin was predominant in HCC tissues. The abnormal expression of β-catenin was correlated with serum AFP levels, cancer cell differentiation and vascular invasion (P<0.05). Additionally, the increased expression of AFP resulted in the upregulation of β-catenin mRNA and protein levels, while knockdown of AFP with AFP shRNA led to significantly decreased β-catenin mRNA and protein levels (P<0.05). It was suggested that the abnormal expression of β-catenin is implicated in hepatic carcinogenesis and development. AFP can lead to increased expression of β-catenin, which may account for the poor prognosis of AFP-associated HCC patients.

Induction of apoptosis in rhabdomyosarcoma cells through down-regulation of PAX proteins

PubMed Central

Bernasconi, Michele; Remppis, Andrew; Fredericks, William J.; Rauscher, Frank J.; Schäfer, Beat W.

1996-01-01

The expression of a number of human paired box-containing (PAX) genes has been correlated with various types of tumors. Novel fusion genes encoding chimeric fusion proteins have been found in the pediatric malignant tumor alveolar rhabdomyosarcoma (RMS). They are generated by two chromosomal translocations t(2;13) and t(1;13) juxtaposing PAX3 or PAX7, respectively, with a forkhead domain gene FKHR. Here we describe that specific down-regulation of the t(2;13) translocation product in alveolar RMS cells by antisense oligonucleotides results in reduced cellular viability. Cells of embryonal RMS, the other major histiotype of this tumor, were found to express either wild type PAX3 or PAX7 at elevated levels when compared with primary human myoblasts. Treatment of corresponding embryonal RMS cells with antisense olignucleotides directed against the mRNA translational start site of either one of these two transcription factors similarly triggers cell death, which is most likely due to induction of apoptosis. Retroviral mediated ectopic expression of mouse Pax3 in a PAX7 expressing embryonal RMS cell line could partially rescue antisense induced apoptosis. These data suggest that the PAX3/FKHR fusion gene and wild-type PAX genes play a causative role in the formation of RMS and presumably other tumor types, possibly by suppressing the apoptotic program that would normally eliminate these cells. PMID:8917562

Cell Wall Modifications in Arabidopsis Plants with Altered α-l-Arabinofuranosidase Activity[C][W

PubMed Central

Chávez Montes, Ricardo A.; Ranocha, Philippe; Martinez, Yves; Minic, Zoran; Jouanin, Lise; Marquis, Mélanie; Saulnier, Luc; Fulton, Lynette M.; Cobbett, Christopher S.; Bitton, Frédérique; Renou, Jean-Pierre; Jauneau, Alain; Goffner, Deborah

2008-01-01

Although cell wall remodeling is an essential feature of plant growth and development, the underlying molecular mechanisms are poorly understood. This work describes the characterization of Arabidopsis (Arabidopsis thaliana) plants with altered expression of ARAF1, a bifunctional α-l-arabinofuranosidase/β-d-xylosidase (At3g10740) belonging to family 51 glycosyl-hydrolases. ARAF1 was localized in several cell types in the vascular system of roots and stems, including xylem vessels and parenchyma cells surrounding the vessels, the cambium, and the phloem. araf1 T-DNA insertional mutants showed no visible phenotype, whereas transgenic plants that overexpressed ARAF1 exhibited a delay in inflorescence emergence and altered stem architecture. Although global monosaccharide analysis indicated only slight differences in cell wall composition in both mutant and overexpressing lines, immunolocalization experiments using anti-arabinan (LM6) and anti-xylan (LM10) antibodies indicated cell type-specific alterations in cell wall structure. In araf1 mutants, an increase in LM6 signal intensity was observed in the phloem, cambium, and xylem parenchyma in stems and roots, largely coinciding with ARAF1 expression sites. The ectopic overexpression of ARAF1 resulted in an increase in LM10 labeling in the secondary walls of interfascicular fibers and xylem vessels. The combined ARAF1 gene expression and immunolocalization studies suggest that arabinan-containing pectins are potential in vivo substrates of ARAF1 in Arabidopsis. PMID:18344421

Epigallocatechin gallate (EGCG) stimulates autophagy in vascular endothelial cells: a potential role for reducing lipid accumulation.

PubMed

Kim, Hae-Suk; Montana, Vedrana; Jang, Hyun-Ju; Parpura, Vladimir; Kim, Jeong-a

2013-08-02

Epigallocatechin gallate (EGCG) is a major polyphenol in green tea that has beneficial effects in the prevention of cardiovascular disease. Autophagy is a cellular process that protects cells from stressful conditions. To determine whether the beneficial effect of EGCG is mediated by a mechanism involving autophagy, the roles of the EGCG-stimulated autophagy in the context of ectopic lipid accumulation were investigated. Treatment with EGCG increased formation of LC3-II and autophagosomes in primary bovine aortic endothelial cells (BAEC). Activation of calmodulin-dependent protein kinase kinase β was required for EGCG-induced LC3-II formation, as evidenced by the fact that EGCG-induced LC3-II formation was significantly impaired by knockdown of calmodulin-dependent protein kinase kinase β. This effect is most likely due to cytosolic Ca(2+) load. To determine whether EGCG affects palmitate-induced lipid accumulation, the effects of EGCG on autophagic flux and co-localization of lipid droplets and autophagolysosomes were examined. EGCG normalized the palmitate-induced impairment of autophagic flux. Accumulation of lipid droplets by palmitate was markedly reduced by EGCG. Blocking autophagosomal degradation opposed the effect of EGCG in ectopic lipid accumulation, suggesting the action of EGCG is through autophagosomal degradation. The mechanism for this could be due to the increased co-localization of lipid droplets and autophagolysosomes. Co-localization of lipid droplets with LC3 and lysosome was dramatically increased when the cells were treated with EGCG and palmitate compared with the cells treated with palmitate alone. Collectively, these findings suggest that EGCG regulates ectopic lipid accumulation through a facilitated autophagic flux and further imply that EGCG may be a potential therapeutic reagent to prevent cardiovascular complications.

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

PubMed Central

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

2014-01-01

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

Premature and ectopic anthocyanin formation by silencing of anthocyanidin reductase in strawberry (Fragaria × ananassa).

PubMed

Fischer, Thilo C; Mirbeth, Beate; Rentsch, Judith; Sutter, Corina; Ring, Ludwig; Flachowsky, Henryk; Habegger, Ruth; Hoffmann, Thomas; Hanke, Magda-Viola; Schwab, Wilfried

2014-01-01

Strawberry (Fragaria × ananassa) is a fruit crop with a distinct biphasic flavonoid biosynthesis. Whereas, in the immature receptacle, high levels of proanthocyanidins accumulate, which are associated with herbivore deterrence and pathogen defense, the prominent color-giving anthocyanins are primarily produced in ripe 'fruits' helping to attract herbivores for seed dispersal. Here, constitutive experimental down-regulation of one branch of proanthocyanidin biosynthesis was performed. As a result, the proportion of epicatechin monomeric units within the proanthocyanidin polymer chains was reduced, but this was not the case for the epicatechin starter unit. Shortened chain lengths of proanthocyanidins were also observed. All enzymatic activities for the production of color-giving anthocyanins were already present in unripe fruits at levels allowing a striking red anthocyanin phenotype in unripe fruits of the RNAi silencing lines. An immediately recognizable phenotype was also observed for the stigmata of flowers, which is another epicatechin-forming tissue. Thus, the down-regulation of anthocyanidin reductase (ANR) induced a redirection of the proanthocyanidin pathway, leading to premature and ectopic anthocyanin biosynthesis via enzymatic glycosylation as the alternative pathway. This redirection is also seen in flavonol biosynthesis, which is paralleled by higher pollen viability in silencing lines. ANRi transgenic lines of strawberry provide a versatile tool for the study of the biological functions of proanthocyanidins. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

Cytoplasm-predominant Pten associates with increased region-specific brain tyrosine hydroxylase and dopamine D2 receptors in mouse model with autistic traits.

PubMed

He, Xin; Thacker, Stetson; Romigh, Todd; Yu, Qi; Frazier, Thomas W; Eng, Charis

2015-01-01

Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders characterized by impairment in social communication/interaction and inflexible/repetitive behavior. Several lines of evidence support genetic factors as a predominant cause of ASD. Among those autism susceptibility genes that have been identified, the PTEN tumor suppressor gene, initially identified as predisposing to Cowden heritable cancer syndrome, was found to be mutated in a subset of ASD patients with extreme macrocephaly. However, the ASD-relevant molecular mechanism mediating the effect of PTEN mutations remains elusive. We developed a Pten knock-in murine model to study the effects of Pten germline mutations, specifically altering subcellular localization, in ASD. Proteins were isolated from the hemispheres of the male littermates, and Western blots were performed to determine protein expression levels of tyrosine hydroxylase (TH). Immunohistochemical stains were carried out to validate the localization of TH and dopamine D2 receptors (D2R). PC12 cells ectopically expressing either wild-type or missense mutant PTEN were then compared for the differences in TH expression. Mice carrying Pten mutations have high TH and D2R in the striatum and prefrontal cortex. They also have increased phosphorylation of cAMP response element-binding protein (CREB) and TH. Mechanistically, PTEN downregulates TH production in PC12 cells via inhibiting the phosphoinositide 3-kinase (PI3K)/CREB signaling pathway, while PTEN reduces TH phosphorylation via suppressing MAPK pathway. Unlike wild-type PTEN but similar to the mouse knock-in mutant Pten, three naturally occurring missense mutations of PTEN that we previously identified in ASD patients, H93R, F241S, and D252G, were not able to suppress TH when overexpressed in PC12 cells. In addition, two other PTEN missense mutations, C124S (pan phosphatase dead) and G129E (lipid phosphatase dead), failed to suppress TH when ectopically expressed in PC12 cells. Our data reveal a non-canonical PTEN-TH pathway in the brain that may work as a core regulator of dopamine signaling, which when dysfunctional is pathogenic in ASD.

Functional activity and tumor-specific expression of dual oxidase 2 in pancreatic cancer cells and human malignancies characterized with a novel monoclonal antibody.

PubMed

Wu, Yonghzong; Antony, Smitha; Hewitt, Stephen M; Jiang, Guojian; Yang, Sherry X; Meitzler, Jennifer L; Juhasz, Agnes; Lu, Jiamo; Liu, Han; Doroshow, James H; Roy, Krishnendu

2013-04-01

Dual oxidase 2 (Duox2), one of the seven members of the NADPH oxidase gene family, plays a critical role in generating H2O2 for thyroid hormone biosynthesis and as an integral part of the host defense system of the respiratory epithelium and the gastrointestinal tract. Recent evidence suggests that the regulation of Duox2 expression is under the control of pro-inflammatory cytokines and that Duox2-induced reactive oxygen species (ROS) contribute to the inflammation-related tissue injury that occurs in two pre-malignant, inflammatory conditions: chronic pancreatitis and inflammatory bowel disease. Because no reliable Duox antibodies are commercially available, we report the development of a murine monoclonal antibody (MAb) to Duox2 (clone Duox S-12) and its use for the characterization of Duox2 expression in human tumors, tumor cell lines and normal tissues. Duox S-12 specifically detected both endogenously- and ectopically-expressed Duox2 protein by immunoblotting, immunofluorescence microscopy and immunohistochemistry (where both membranous and cytoplasmic staining were present). Duox2 expression detected by Duox S-12 was functionally coupled to the generation of H(2)O(2) in pancreatic cancer cells that expressed Duox2 and its cognate maturation factor DuoxA2. Although Duox S-12 recognizes ectopically expressed Duox1 protein because of the extensive amino acid homology between Duox1 and Duox2, the lack of substantial Duox1 mRNA expression in human tumors (except thyroid cancer) allowed us to evaluate Duox2 expression across a wide range of normal and malignant tissues by immuno-histochemistry. Duox2 was expressed at elevated levels in many human cancers, most notably tumors of the prostate, lung, colon and breast while brain tumors and lymphomas demonstrated the lowest frequency of expression. The Duox-specific monoclonal antibody described here provides a promising tool for the further examination of the role of Duox-dependent reactive oxygen production in inflammation-related carcinogenesis, where alterations in oxidant tone play a critical role in cell growth and proliferation.

Somatic hypermutation and antigen-driven selection of B cells are altered in autoimmune diseases.

PubMed

Zuckerman, Neta S; Hazanov, Helena; Barak, Michal; Edelman, Hanna; Hess, Shira; Shcolnik, Hadas; Dunn-Walters, Deborah; Mehr, Ramit

2010-12-01

B cells have been found to play a critical role in the pathogenesis of several autoimmune (AI) diseases. A common feature amongst many AI diseases is the formation of ectopic germinal centers (GC) within the afflicted tissue or organ, in which activated B cells expand and undergo somatic hypermutation (SHM) and antigen-driven selection on their immunoglobulin variable region (IgV) genes. However, it is not yet clear whether these processes occurring in ectopic GCs are identical to those in normal GCs. The analysis of IgV mutations has aided in revealing many aspects concerning B cell expansion, mutation and selection in GC reactions. We have applied several mutation analysis methods, based on lineage tree construction, to a large set of data, containing IgV productive and non-productive heavy and light chain sequences from several different tissues, to examine three of the most profoundly studied AI diseases - Rheumatoid Arthritis (RA), Multiple Sclerosis (MS) and Sjögren's Syndrome (SS). We have found that RA and MS sequences exhibited normal mutation spectra and targeting motifs, but a stricter selection compared to normal controls, which was more apparent in RA. SS sequence analysis results deviated from normal controls in both mutation spectra and indications of selection, also showing differences between light and heavy chain IgV and between different tissues. The differences revealed between AI diseases and normal control mutation patterns may result from the different microenvironmental influences to which ectopic GCs are exposed, relative to those in normal secondary lymphoid tissues. Copyright © 2010 Elsevier Ltd. All rights reserved.

Characterization of porcine partially reprogrammed iPSCs from adipose-derived stem cells.

PubMed

Wei, Chao; Li, Xia; Zhang, Pengfei; Zhang, Yu; Liu, Tong; Jiang, Shaoshuai; Han, Fei; Zhang, Yunhai

2015-05-01

Partially reprogrammed induced pluripotent stem cells (PiPSCs) have great potential for investigating reprogramming mechanisms and represent an alternative potential material for making genetically modified animals and regenerative medicine. To date, PiPSCs have scarcely been reported in detail when compared with mice and humans. In this study, we obtained PiPSCs from porcine adipose-derived stem cells (pADSCs) by ectopic expression of human transcription factors (OCT4, SOX2, c-MYC, and KLF4) in feeder-free condition. The morphology and proliferation activity of porcine PiPSCs (pPiPSCs) were similar to those of porcine fully reprogrammed iPSCs (pFiPSCs); furthermore, pPiPSCs expressed higher levels of the typical surface molecules (CD29) found in pADSCs. However, pPiPSCs were negative for key proteins (NANOG) connected with stemness and possessed lower differentiation ability in vivo and in vitro. When differentiation-inhibiting factors were withdrawn, pPiPSCs-derived cells (pPiPSC-DCs) showed similar features to pADSCs in many aspects, including proliferation, differentiation, and immunosuppression. When both types of cells were used to produce cloned embryos, we found that the blastocyst formation rate of 19DC (one of the pPiPSC-DC cell lines)-derived cloned embryos was obviously higher than that of others. The total cell number of 19DC-derived blastocysts was significantly higher than the 30DC (one pFiPSC-DC cell line)-derived blastocysts. In all, through limited differentiation ability, the proliferation activity of pPiPSCs is similar to that of pFiPSCs, and pPiPSCs can retain several of the features of pADSCs, which are beneficial to cell therapy. Furthermore, the differentiation of pPiPSCs is more favorable for producing high-quality reconstructed embryos. © 2015 Society for Reproduction and Fertility.

Dual acylation and lipid raft association of Src-family protein tyrosine kinases are required for SDF-1/CXCL12-mediated chemotaxis in the Jurkat human T cell lymphoma cell line.

PubMed

Zaman, Sabiha N; Resek, Mary E; Robbins, Stephen M

2008-10-01

Chemokines play pivotal roles in regulating a wide variety of biological processes by modulating cell migration and recruitment. Deregulation of chemokine signaling can alter cell recruitment, contributing to the pathogenic states associated with autoimmune disease, inflammatory disorders, and sepsis. During chemotaxis, lipid rafts and their resident signaling molecules have been demonstrated to partition to different parts of the cell. Herein, we investigated the role of lipid raft resident Src-family kinases (SFK) in stromal cell-derived factor 1/CXCL12-mediated chemotaxis. We have shown that Lck-deficient J.CaM 1.6 cells are defective in CXCL12-mediated chemotaxis in contrast to their parental counterpart, Jurkat cells. Ectopic expression of the SFK hematopoietic cell kinase (Hck) in J.CaM 1.6 cells reconstituted CXCL12 responsiveness. The requirement of lipid raft association of SFK was assessed using both isoforms of Hck: the dually acylated p59(Hck) isoform that is targeted to lipid rafts and the monoacylated p61(Hck) isoform that is nonraft-associated. We have shown using several gain and loss of acylation alleles that dual acylation of Hck was required for CXCL12-mediated chemotaxis in J.CaM 1.6 cells. These results highlight the importance of the unique microenvironment provided by lipid rafts and their specific contribution in providing specificity to CXCL12 signaling.

Proteomics Identification of Annexin A2 as a Key Mediator in the Metastasis and Proangiogenesis of Endometrial Cells in Human Adenomyosis*

PubMed Central

Zhou, Shengtao; Yi, Tao; Liu, Rui; Bian, Ce; Qi, Xiaorong; He, Xiang; Wang, Kui; Li, Jingyi; Zhao, Xia; Huang, Canhua; Wei, Yuquan

2012-01-01

Adenomyosis is a common estrogen-dependent disorder of females characterized by a downward extension of the endometrium into the uterine myometrium and neovascularization in ectopic lesions. It accounts for chronic pelvic pain, dysmenorrhea, menorrhagia, and infertility in 8.8–61.5% women worldwide. However, the molecular mechanisms for adenomyosis development remain poorly elucidated. Here, we utilized a two-dimensional polyacrylamide gel electrophoresis/MS-based proteomics analysis to compare and identify differentially expressed proteins in matched ectopic and eutopic endometrium of adenomyosis patients. A total of 93 significantly altered proteins were identified by tandem MS analysis. Further cluster analysis revealed a group of estrogen-responsive proteins as dysregulated in adenomyosis, among which annexin A2, a member of annexin family proteins, was found up-regulated most significantly in the ectopic endometrium of adenomyosis compared with its eutopic counterpart. Overexpression of ANXA2 was validated in ectopic lesions of human adenomyosis and was found to be tightly correlated with markers of epithelial to mesenchymal transition and dysmenorrhea severity of adenomyosis patients. Functional analysis demonstrated that estrogen could remarkably up-regulate ANXA2 and induce epithelial to mesenchymal transition in an in vitro adenomyosis model. Enforced expression of ANXA2 could mediate phenotypic mesenchymal-like cellular changes, with structural and functional alterations in a β-catenin/T-cell factor (Tcf) signaling-associated manner, which could be reversed by inhibition of ANXA2 expression. We also proved that enforced expression of ANXA2 enhanced the proangiogenic capacity of adenomyotic endometrial cells through HIF-1α/VEGF-A pathway. In vivo, we demonstrated that ANXA2 inhibition abrogated endometrial tissue growth, metastasis, and angiogenesis in an adenomyosis nude mice model and significantly alleviated hyperalgesia. Taken together, our data unraveled a dual role for ANXA2 in the pathogenesis of human adenomyosis through conferring endometrial cells both metastatic potential and proangiogenic capacity, which could serve as a potential therapeutic target for the treatment of adenomyosis patients. PMID:22493182

To Assess the Association between Glucose Metabolism and Ectopic Lipid Content in Different Clinical Classifications of PCOS.

PubMed

Göbl, Christian S; Ott, Johannes; Bozkurt, Latife; Feichtinger, Michael; Rehmann, Victoria; Cserjan, Anna; Heinisch, Maike; Steinbrecher, Helmut; JustKukurova, Ivica; Tuskova, Radka; Leutner, Michael; Vytiska-Binstorfer, Elisabeth; Kurz, Christine; Weghofer, Andrea; Tura, Andrea; Egarter, Christian; Kautzky-Willer, Alexandra

2016-01-01

There are emerging data indicating an association between PCOS (polycystic ovary syndrome) and metabolic derangements with potential impact on its clinical presentation. This study aims to evaluate the pathophysiological processes beyond PCOS with particular focus on carbohydrate metabolism, ectopic lipids and their possible interaction. Differences between the two established classifications of the disease should be additionally evaluated. A metabolic characterization was performed in 53 untreated PCOS patients as well as 20 controls including an extended oral glucose tolerance test (OGTT, to assess insulin sensitivity, secretion and ß-cell function) in addition to a detailed examination of ectopic lipid content in muscle and liver by nuclear magnetic resonance spectroscopy. Women with PCOS classified by the original NIH 1990 definition showed a more adverse metabolic risk profile compared to women characterized by the additional Rotterdam 2003 phenotypes. Subtle metabolic derangements were observed in both subgroups, including altered shapes of OGTT curves, impaired insulin action and hyperinsulinemia due to increased secretion and attenuated hepatic extraction. No differences were observed for ectopic lipids between the groups. However, particularly hepatocellular lipid content was significantly related to clinical parameters of PCOS like whole body insulin sensitivity, dyslipidemia and free androgen index. Subtle alterations in carbohydrate metabolism are present in both PCOS classifications, but more profound in subjects meeting the NIH 1990 criteria. Females with PCOS and controls did not differ in ectopic lipids, however, liver fat was tightly related to hyperandrogenism and an adverse metabolic risk profile.

Ectopic osteogenesis and angiogenesis regulated by porous architecture of hydroxyapatite scaffolds with similar interconnecting structure in vivo

PubMed Central

Li, Jinyu; Zhi, Wei; Xu, Taotao; Shi, Feng; Duan, Ke; Wang, Jianxin; Mu, Yandong; Weng, Jie

2016-01-01

The macro-pore sizes of porous scaffold play a key role for regulating ectopic osteogenesis and angiogenesis but many researches ignored the influence of interconnection between macro-pores with different sizes. In order to accurately reveal the relationship between ectopic osteogenesis and macro-pore sizes in dorsal muscle and abdominal cavities of dogs, hydroxyapatite (HA) scaffolds with three different macro-pore sizes of 500–650, 750–900 and 1100–1250 µm were prepared via sugar spheres-leaching process, which also had similar interconnecting structure determined by keeping the d/s ratio of interconnecting window diameter to macro-pore size constant. The permeability test showed that the seepage flow of fluid through the porous scaffolds increased with the increase of macro-pore sizes. The cell growth in three scaffolds was not affected by the macro-pore sizes. The in vivo ectopic implantation results indicated that the macro-pore sizes of HA scaffolds with the similar interconnecting structure have impact not only the speed of osteogenesis and angiogenesis but also the space distribution of newly formed bone. The scaffold with macro-pore sizes of 750–900 µm exhibited much faster angiogenesis and osteogenesis, and much more uniformly distribution of new bone than those with other macro-pore sizes. This work illustrates the importance of a suitable macro-pore sizes in HA scaffolds with the similar interconnecting structure which provides the environment for ectopic osteogenesis and angiogenesis. PMID:27699059

Ectopic recombination between Ty elements in Saccharomyces cerevisiae is not induced by DNA damage.

PubMed

Parket, A; Kupiec, M

1992-10-01

Mitotic recombination is increased when cells are treated with a variety of physical and chemical agents that cause damage to their DNA. We show here, using Saccharomyces cerevisiae strains that carry marked Ty elements, that recombination between members of this family of retrotransposons is not increased by UV irradiation or by treatment with the radiomimetic drug methyl methanesulfonate. Both ectopic recombination and mutation events were elevated by these agents for non-Ty sequences in the same strain. We discuss possible mechanisms that can prevent the induction of recombination between Ty elements.

G Protein-Coupled Estrogen Receptor (GPER) Expression in Normal and Abnormal Endometrium

PubMed Central

Lessey, Bruce A.; Taylor, Robert N.; Wang, Wei; Bagchi, Milan K.; Yuan, Lingwen; Scotchie, Jessica; Fritz, Marc A.; Young, Steven L.

2012-01-01

Rapid estrogen effects are mediated by membrane receptors, and evidence suggests a role for both a membrane-associated form of estrogen receptor alpha (ESR1; ERα) and G-protein coupled receptor 30 (GPER; GPR30). Considering estrogen’s importance in endometrial physiology and endometriosis pathophysiology, we hypothesized that GPER could be involved in both cyclic changes in endometrial estrogen action and that aberrant expression might be seen in the eutopic endometrium of women with endometriosis. Using real-time reverse transcriptase–polymerase chain reaction (RT-PCR) and immunohistochemical analysis of normal endometrium, endometrial samples demonstrated cycle-regulated expression of GPER, with maximal expression in the proliferative phase. Eutopic and ectopic endometrium from women with endometriosis overexpressed GPER as compared to eutopic endometrium of normal participants. Ishikawa cells, an adenocarcinoma cell line, expressed GPER, with increased expression upon treatment with estrogen or an ESR1 agonist, but not with a GPER-specific agonist. Decreased expression was seen in Ishikawa cells stably transfected with progesterone receptor A. Together, these data suggest that normal endometrial GPER expression is cyclic and regulated by nuclear estrogen and progesterone receptors, while expression is dysregulated in endometriosis. PMID:22378861

G protein-coupled estrogen receptor (GPER) expression in normal and abnormal endometrium.

PubMed

Plante, Beth J; Lessey, Bruce A; Taylor, Robert N; Wang, Wei; Bagchi, Milan K; Yuan, Lingwen; Scotchie, Jessica; Fritz, Marc A; Young, Steven L

2012-07-01

Rapid estrogen effects are mediated by membrane receptors, and evidence suggests a role for both a membrane-associated form of estrogen receptor alpha (ESR1; ERα) and G-protein coupled receptor 30 (GPER; GPR30). Considering estrogen's importance in endometrial physiology and endometriosis pathophysiology, we hypothesized that GPER could be involved in both cyclic changes in endometrial estrogen action and that aberrant expression might be seen in the eutopic endometrium of women with endometriosis. Using real-time reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemical analysis of normal endometrium, endometrial samples demonstrated cycle-regulated expression of GPER, with maximal expression in the proliferative phase. Eutopic and ectopic endometrium from women with endometriosis overexpressed GPER as compared to eutopic endometrium of normal participants. Ishikawa cells, an adenocarcinoma cell line, expressed GPER, with increased expression upon treatment with estrogen or an ESR1 agonist, but not with a GPER-specific agonist. Decreased expression was seen in Ishikawa cells stably transfected with progesterone receptor A. Together, these data suggest that normal endometrial GPER expression is cyclic and regulated by nuclear estrogen and progesterone receptors, while expression is dysregulated in endometriosis.

Association of T-Zone Reticular Networks and Conduits with Ectopic Lymphoid Tissues in Mice and Humans

PubMed Central

Link, Alexander; Hardie, Debbie L.; Favre, Stéphanie; Britschgi, Mirjam R.; Adams, David H.; Sixt, Michael; Cyster, Jason G.; Buckley, Christopher D.; Luther, Sanjiv A.

2011-01-01

Ectopic or tertiary lymphoid tissues (TLTs) are often induced at sites of chronic inflammation. They typically contain various hematopoietic cell types, high endothelial venules, and follicular dendritic cells; and are organized in lymph node–like structures. Although fibroblastic stromal cells may play a role in TLT induction and persistence, they have remained poorly defined. Herein, we report that TLTs arising during inflammation in mice and humans in a variety of tissues (eg, pancreas, kidney, liver, and salivary gland) contain stromal cell networks consisting of podoplanin+ T-zone fibroblastic reticular cells (TRCs), distinct from follicular dendritic cells. Similar to lymph nodes, TRCs were present throughout T-cell–rich areas and had dendritic cells associated with them. They expressed lymphotoxin (LT) β receptor (LTβR), produced CCL21, and formed a functional conduit system. In rat insulin promoter–CXCL13–transgenic pancreas, the maintenance of TRC networks and conduits was partially dependent on LTβR and on lymphoid tissue inducer cells expressing LTβR ligands. In conclusion, TRCs and conduits are hallmarks of secondary lymphoid organs and of well-developed TLTs, in both mice and humans, and are likely to act as important scaffold and organizer cells of the T-cell–rich zone. PMID:21435450

A gain-of-function screen for genes that influence axon guidance identifies the NF-kappaB protein dorsal and reveals a requirement for the kinase Pelle in Drosophila photoreceptor axon targeting.

PubMed

Mindorff, Elizabeth N; O'Keefe, David D; Labbé, Alain; Yang, Jennie Ping; Ou, Yimiao; Yoshikawa, Shingo; van Meyel, Donald J

2007-08-01

To identify novel regulators of nervous system development, we used the GAL4-UAS misexpression system in Drosophila to screen for genes that influence axon guidance in developing embryos. We mobilized the Gene Search (GS) P element and identified 42 lines with insertions in unique loci, including leak/roundabout2, which encodes an axon guidance receptor and confirms the utility of our screen. The genes we identified encode proteins of diverse classes, some acting near the cell surface and others in the cytoplasm or nucleus. We found that one GS line drove misexpression of the NF-kappaB transcription factor Dorsal, causing motor axons to bypass their correct termination sites. In the developing visual system, Dorsal misexpression also caused photoreceptor axons to reach incorrect positions within the optic lobe. This mistargeting occurred without observable changes of cell fate and correlated with localization of ectopic Dorsal in distal axons. We found that Dorsal and its inhibitor Cactus are expressed in photoreceptors, though neither was required for axon targeting. However, mutation analyses of genes known to act upstream of Dorsal revealed a requirement for the interleukin receptor-associated kinase family kinase Pelle for layer-specific targeting of photoreceptor axons, validating our screen as a means to identify new molecular determinants of nervous system development in vivo.

Jaw1/LRMP has a role in maintaining nuclear shape via interaction with SUN proteins.

PubMed

Kozono, Takuma; Tadahira, Kazuko; Okumura, Wataru; Itai, Nao; Tamura-Nakano, Miwa; Dohi, Taeko; Tonozuka, Takashi; Nishikawa, Atsushi

2018-06-06

Jaw1/LRMP is characterized as a type II integral membrane protein that is localized to endoplasmic reticulum (ER), however, its physiological functions have been poorly understood. An alignment of amino acid sequence of Jaw1 with KASH proteins, outer nuclear membrane proteins, revealed that Jaw1 has a partial homology to the KASH domain. Here, we show that the function of Jaw1 is to maintain nuclear shape in mouse melanoma cell line. The siRNA-mediated knockdown of Jaw1 caused a severe defect in nuclear shape, and the defect was rescued by ectopic expression of siRNA-resistant Jaw1. Since co-immunoprecipitation assay indicates that Jaw1 interacts with SUN proteins that are inner nuclear proteins and microtubules, this study suggests that Jaw1 has a role in maintaining nuclear shape via interactions with SUN proteins and microtubules.

Expression of natural killer cell activity with CD107a on ectopic endometrium in woman with endometriosis compared with non-endometriosis

NASA Astrophysics Data System (ADS)

Lubis, H. P.; Aldiansyah, D.; Siregar, H. S.; Rivany, R.; Hariadi, T. S.

2018-03-01

Some factors have an important role in endometriosis pathogenesis; there is an immune cell that plays an important role in endometrial cells that have reflux. Woman with endometriosis experienced the cellular immune disorder. It is suspected that decrease of NK cell in the peritoneal fluid caused by its qualitative defect with CD107a expression as the best marker. The aim of this study was to compare expression of NK Cell activity with CD107a between awoman with endometriosis and non-endometriosis. A case-control study from March until July 2015 in Haji Adam Malik General Hospital. The case group was ectopic endometrial tissue block paraffin and control group was normal endometrial tissue block paraffin. This study included 23 patients in endometriosis group and control group respectively. A majority proportion of CD107a expression in endometriosis group was +1 (16 patients (69.6%)), while the control group was +3 (9 patients (39.1%)). Expression of NK cell activity with CD107a in patients with endometriosis was lower than the control group (p<0.05). It suggested that cellular immune factors may play a role in the pathogenesis of endometriosis.

Glycosylphosphatidylinositol-anchored proteins are required for cell wall synthesis and morphogenesis in Arabidopsis.

PubMed

Gillmor, C Stewart; Lukowitz, Wolfgang; Brininstool, Ginger; Sedbrook, John C; Hamann, Thorsten; Poindexter, Patricia; Somerville, Chris

2005-04-01

Mutations at five loci named PEANUT1-5 (PNT) were identified in a genetic screen for radially swollen embryo mutants. pnt1 cell walls showed decreased crystalline cellulose, increased pectins, and irregular and ectopic deposition of pectins, xyloglucans, and callose. Furthermore, pnt1 pollen is less viable than the wild type, and pnt1 embryos were delayed in morphogenesis and showed defects in shoot and root meristems. The PNT1 gene encodes the Arabidopsis thaliana homolog of mammalian PIG-M, an endoplasmic reticulum-localized mannosyltransferase that is required for synthesis of the glycosylphosphatidylinositol (GPI) anchor. All five pnt mutants showed strongly reduced accumulation of GPI-anchored proteins, suggesting that they all have defects in GPI anchor synthesis. Although the mutants are seedling lethal, pnt1 cells are able to proliferate for a limited time as undifferentiated callus and do not show the massive deposition of ectopic cell wall material seen in pnt1 embryos. The different phenotype of pnt1 cells in embryos and callus suggest a differential requirement for GPI-anchored proteins in cell wall synthesis in these two tissues and points to the importance of GPI anchoring in coordinated multicellular growth.

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

Ectopic expression of anti-HIV-1 shRNAs protects CD8{sup +} T cells modified with CD4ζ CAR from HIV-1 infection and alleviates impairment of cell proliferation

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

Kamata, Masakazu, E-mail: masa3k@ucla.edu; Kim, Patrick Y.; Ng, Hwee L.

Chimeric antigen receptors (CARs) are artificially engineered receptors that confer a desired specificity to immune effector T cells. As an HIV-1-specific CAR, CD4ζ CAR has been extensively tested in vitro as well as in clinical trials. T cells modified with this CAR mediated highly potent anti-HIV-1 activities in vitro and were well-tolerated in vivo, but exerted limited effects on viral load and reservoir size due to poor survival and/or functionality of the transduced cells in patients. We hypothesize that ectopic expression of CD4ζ on CD8{sup +} T cells renders them susceptible to HIV-1 infection, resulting in poor survival of those cells. To testmore » this possibility, highly purified CD8{sup +} T cells were genetically modified with a CD4ζ-encoding lentiviral vector and infected with HIV-1. CD8{sup +} T cells were vulnerable to HIV-1 infection upon expression of CD4ζ as evidenced by elevated levels of p24{sup Gag} in cells and culture supernatants. Concurrently, the number of CD4ζ-modified CD8{sup +} T cells was reduced relative to control cells upon HIV-1 infection. To protect these cells from HIV-1 infection, we co-expressed two anti-HIV-1 shRNAs previously developed by our group together with CD4ζ. This combination vector was able to suppress HIV-1 infection without impairing HIV-1-dependent effector activities of CD4ζ. In addition, the number of CD4ζ-modified CD8{sup +} T cells maintained similar levels to that of the control even under HIV-1 infection. These results suggest that protecting CD4ζ-modified CD8{sup +} T cells from HIV-1 infection is required for prolonged HIV-1-specific immune surveillance. - Highlights: • Ectopic expression of CD4ζ CAR in CD8{sup +} T cells renders them susceptible to HIV-1 infection. • Co-expression of two anti-HIV-1 shRNAs protects CD4ζ CAR-modified CD8{sup +} T cells from HIV-1 infection. • Protecting CD4ζ CAR-modified CD8{sup +} T cells from HIV-1 infection suppresses its cytopathic effect.« less

PVT1-derived miR-1207-5p promotes breast cancer cell growth by targeting STAT6.

PubMed

Yan, Chen; Chen, Yaqing; Kong, Weiwei; Fu, Liya; Liu, Yunde; Yao, Qingjuan; Yuan, Yuhua

2017-05-01

Accumulating evidence indicates that ectopic expression of non-coding RNAs are responsible for breast cancer progression. Increased non-coding RNA PVT1, the host gene of microRNA-1207-5p (miR-1207-5p), has been associated with breast cancer proliferation. However, how PVT1 functions in breast cancer is still not clear. In this study, we show a PVT1-derived microRNA, miR-1207-5p, that promotes the proliferation of breast cancer cells by directly regulating STAT6. We first confirm the positive correlated expression pattern between PVT1 and miR-1207-5p by observing consistent induced expression by estrogen, and overexpression in breast cancer cell lines and breast cancer patient specimens. Moreover, silence of PVT1 also decreased miR-1207-5p expression. Furthermore, increased miR-1207-5p expression promoted, while decreased miR-1207-5p expression suppressed, cell proliferation, colony formation, and cell cycle progression in breast cancer cell lines. Mechanistically, a novel target of miR-1207-5p, STAT6, was identified by a luciferase reporter assay. Overexpression of miR-1207-5p decreased the levels of STAT6, which activated CDKN1A and CDKN1B to regulate the cell cycle. We also confirmed the reverse correlation of miR-1207-5p and STAT6 expression levels in breast cancer samples. Therefore, our findings reveal that PVT1-derived miR-1207-5p promotes the proliferation of breast cancer cells by targeting STAT6, which in turn controls CDKN1A and CDKN1B expression. These findings suggest miR-1207-5p might be a potential target for breast cancer therapy. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

F-box protein FBXL2 targets cyclin D2 for ubiquitination and degradation to inhibit leukemic cell proliferation

PubMed Central

Chen, Bill B.; Glasser, Jennifer R.; Coon, Tiffany A.; Zou, Chunbin; Miller, Hannah L.; Fenton, Moon; McDyer, John F.; Boyiadzis, Michael

2012-01-01

Hematologic maligancies exhibit a growth advantage by up-regulation of components within the molecular apparatus involved in cell-cycle progression. The SCF (Skip-Cullin1-F-box protein) E3 ligase family provides homeostatic feedback control of cell division by mediating ubiquitination and degradation of cell-cycle proteins. By screening several previously undescribed E3 ligase components, we describe the behavior of a relatively new SCF subunit, termed FBXL2, that ubiquitinates and destabilizes cyclin D2 protein leading to G0 phase arrest and apoptosis in leukemic and B-lymphoblastoid cell lines. FBXL2 expression was strongly suppressed, and yet cyclin D2 protein levels were robustly expressed in acute myelogenous leukemia (AML) and acute lymphoblastic leukemia (ALL) patient samples. Depletion of endogenous FBXL2 stabilized cyclin D2 levels, whereas ectopically expressed FBXL2 decreased cyclin D2 lifespan. FBXL2 did not bind a phosphodegron within its substrate, which is typical of other F-box proteins, but uniquely targeted a calmodulin-binding signature within cyclin D2 to facilitate its polyubiquitination. Calmodulin competes with the F-box protein for access to this motif where it bound and protected cyclin D2 from FBXL2. Calmodulin reversed FBXL2-induced G0 phase arrest and attenuated FBXL2-induced apoptosis of lymphoblastoid cells. These results suggest an antiproliferative effect of SCFFBXL2 in lymphoproliferative malignancies. PMID:22323446

Long Noncoding RNA LINC00958 Accelerates Gliomagenesis Through Regulating miR-203/CDK2.

PubMed

Guo, Erkun; Liang, Chaohui; He, Xin; Song, Guozhi; Liu, Hongjiang; Lv, Zhongqiang; Guan, Jianchao; Yang, Dezhen; Zheng, Jiapeng

2018-05-01

Increasing evidence has indicated that long noncoding RNAs (lncRNAs) play crucial roles in various biological processes, including glioma. However, the underlying mechanism of lncRNAs in gliomagenesis is still ambiguous. In this study, we aim to investigate the role of long intergenic noncoding RNA 00958 (LINC00958) in the tumorigenesis of glioma. Results revealed that LINC00958 was significantly upregulated in glioma tissues and cell lines compared with that of adjacent normal brain tissues and normal human astrocytes. Moreover, the ectopic overexpression of LINC00958 was correlated with poor prognosis of glioma patients. Loss-of-function experiments indicated that LINC00958 knockdown suppressed glioma cell proliferation, invasion, and induced cycle arrest at G0/G1 phase in vitro, and inhibited tumor growth in vivo. Bioinformatics programs and luciferase reporter assay revealed that miR-203 shared complementary binding sites with both 3'-untranslated region of LINC00958 and CDK2. In summary, our study concludes that LINC00958 acts as an oncogenic gene in the gliomagenesis through miR-203-CDK2 regulation, providing a novel insight into glioma tumorigenesis.

Intra-tumoral delivery of functional ID4 protein via PCL/maltodextrin nano-particle inhibits prostate cancer growth

PubMed Central

Morton, Derrick; Sharma, Pankaj; Gorantla, Yamini; Joshi, Jugal; Nagappan, Perri; Pallaniappan, Ravi; Chaudhary, Jaideep

2016-01-01

ID4, a helix loop helix transcriptional regulator has emerged as a tumor suppressor in prostate cancer. Epigenetic silencing of ID4 promotes prostate cancer whereas ectopic expression in prostate cancer cell lines blocks cancer phenotype. To directly investigate the anti-tumor property, full length human recombinant ID4 encapsulated in biodegradable Polycaprolactone/Maltodextrin (PCL-MD) nano-carrier was delivered to LNCaP cells in which the native ID4 was stably silenced (LNCaP(-)ID4). The cellular uptake of ID4 resulted in increased apoptosis, decreased proliferation and colony formation. Intratumoral delivery of PCL-MD ID4 into growing LNCaP(-)ID4 tumors in SCID mice significantly reduced the tumor volume compared to the tumors treated with chemotherapeutic Docetaxel. The study supports the feasibility of using nano-carrier encapsulated ID4 protein as a therapeutic. Mechanistically, ID4 may assimilate multiple regulatory pathways for example epigenetic re-programming, integration of multiple AR co-regulators or signaling pathways resulting in tumor suppressor activity of ID4. PMID:27487149

[Effect of LPXN Overexpression on the Proliferation, Adhesion and Invasion of THP-1 Cells and Its Mechamisms].

PubMed

Dai, Hai-Ping; Zhu, Guo-Hua; Wu, Li-Li; Wang, Qian; Yao, Hong; Wang, Qin-Rong; Wen, Li-Jun; Qiu, Hui-Ying; Shen, Qun; Chen, Su-Ning; Wu, De-Pei

2017-06-01

To explore the effect of LPXN overexpression on the proliferation, adhesion and invasion of THP-1 cells and its possible mechanism. A THP-1 cell line with stable overexpression of LPXN was constucted by using a lentivirus method, CCK-8 was used to detect the proliferation of cells, adhesion test was used to evaluate adhesion ablity of cells to Fn. Transwell assay was used to detect the change of invasion capability. Western blot was used to detect expression of LPXN, ERK, pERK and integrin α4, α5, β1, the Gelatin zymography was applied to detect activity of MMP2/MMP9 secreted by the THP-1 cells. Successful establishment of THP-1 cells with LPXN overexpression (THP-1 LPXN) was confirmed with Western blot. THP-1 LPXN cells were shown to proliferate faster than the control THP-1 vector cells. Adhesion to Fn and expression of ERK, integrin α4, α5 and β1 in the THP-1 LPXN cells were higher than that in the control cells. Invasion across matrigel and enhanced activity of MMP2 could be detected both in the THP-1 LPXN cells as compared with the control cells. Ectopically ovexpression of LPXN may promote proliferation of THP-1 cells through up-regulation of ERK; promote adhesion of THP-1 cells through up-regulating the integrin α4/β1 as well as integrin α5/β1 complex; promote invasion of THP-1 cells through activating MMP2.

TNFα-induced IKKβ complex activation influences epithelial, but not stromal cell survival in endometriosis.

PubMed

Kocbek, Vida; Grandi, Giovanni; Blank, Fabian; Wotzkow, Carlos; Bersinger, Nick A; Mueller, Michael D; Kyo, Satoru; McKinnon, Brett D

2016-11-01

Can the activity of the IκB kinase (IKKβ) complex in endometriotic cells contribute to endometriotic lesion survival? There is a constitutive activity of the IKKβ catalytic complex in peritoneal and deeply infiltrating lesions that can influence epithelial, but not stromal cell viability. Endometriotic lesions exist in an inflammatory microenvironment with higher local concentrations of cytokines, such as tumour necrosis factor α (TNFα). TNFα stimulates the activation of the IKKβ complex, an important nodal point in multiple signalling pathways that influence gene transcription, proliferation and apoptosis. However, few data on the regulation of IKKβ in endometriotic tissue are currently available. A retrospective analysis of endometriotic tissue from peritoneal, ovarian and deeply infiltrating lesions from 37 women. Basal and activated (phosphorylated) IKKβ concentrations were analysed by western blotting and immunohistochemistry. The relationship between the expression and activation of these proteins and peritoneal fluid (TNFα) concentrations, measured via ELISA, was examined. A subsequent in vitro analysis of TNFα treatment on the activation of IKKβ and the effect on epithelial and stromal cell viability by its inhibition with PS1145 was also performed. Levels of the phosphorylated IKKβ complex in endometriotic lesions had a significant positive correlation with peritoneal fluid TNFα concentrations. Phosphorylated IKKβ complex was more prevalent in peritoneal and deeply infiltrating endometriosis lesions compared with ovarian lesions. IKKβ was present in both epithelial and stromal cells in all lesions but active IKKβ was limited to epithelial cells. TNFα stimulated an increased expression of phosphorylated IKKβ and the inhibition of this kinase with PS1145 significantly influenced ectopic epithelial cells viability but not eutopic epithelial cells, or endometrial stromal cells. In vitro analysis on epithelial cells was performed with immortalized cell lines and not primary cell cultures and only low sample numbers were available for the study. The regulation of aberrant signalling pathways represents a promising yet relatively unexplored area of endometriosis progression. The IKKβ complex is activated by inflammation and is critical nodal point of numerous downstream kinase-signalling pathways, including NFκB (nuclear factor κB), mTOR (mammalian target of rapamycin) and BAD (Bcl2-antagonist of cell death). This study shows a significant relationship between peritoneal fluid TNFα and IKKβ activation in epithelial cells that will have significant consequences for the continued survival of these cells at ectopic locations through the regulation of downstream pathways. None. The study was funded by the Swiss National Science Foundation (Grant Number 320030_140774). The authors have no conflict of interest to declare. © The Author 2016. 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.

Target of rapamycin signaling orchestrates growth-defense trade-offs in plants.

PubMed

De Vleesschauwer, David; Filipe, Osvaldo; Hoffman, Gena; Seifi, Hamed Soren; Haeck, Ashley; Canlas, Patrick; Van Bockhaven, Jonas; De Waele, Evelien; Demeestere, Kristof; Ronald, Pamela; Hofte, Monica

2018-01-01

Plant defense to microbial pathogens is often accompanied by significant growth inhibition. How plants merge immune system function with normal growth and development is still poorly understood. Here, we investigated the role of target of rapamycin (TOR), an evolutionary conserved serine/threonine kinase, in the plant defense response. We used rice as a model system and applied a combination of chemical, genetic, genomic and cell-based analyses. We demonstrate that ectopic expression of TOR and Raptor (regulatory-associated protein of mTOR), a protein previously demonstrated to interact with TOR in Arabidopsis, positively regulates growth and development in rice. Transcriptome analysis of rice cells treated with the TOR-specific inhibitor rapamycin revealed that TOR not only dictates transcriptional reprogramming of extensive gene sets involved in central and secondary metabolism, cell cycle and transcription, but also suppresses many defense-related genes. TOR overexpression lines displayed increased susceptibility to both bacterial and fungal pathogens, whereas plants with reduced TOR signaling displayed enhanced resistance. Finally, we found that TOR antagonizes the action of the classic defense hormones salicylic acid and jasmonic acid. Together, these results indicate that TOR acts as a molecular switch for the activation of cell proliferation and plant growth at the expense of cellular immunity. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

Aberrant Retinoblastoma (RB)-E2F Transcriptional Regulation Defines Molecular Phenotypes of Osteosarcoma*

PubMed Central

Scott, Milcah C.; Sarver, Aaron L.; Tomiyasu, Hirotaka; Cornax, Ingrid; Van Etten, Jamie; Varshney, Jyotika; O'Sullivan, M. Gerard; Subramanian, Subbaya; Modiano, Jaime F.

2015-01-01

We previously identified two distinct molecular subtypes of osteosarcoma through gene expression profiling. These subtypes are associated with distinct tumor behavior and clinical outcomes. Here, we describe mechanisms that give rise to these molecular subtypes. Using bioinformatic analyses, we identified a significant association between deregulation of the retinoblastoma (RB)-E2F pathway and the molecular subtype with worse clinical outcomes. Xenotransplantation models recapitulated the corresponding behavior for each osteosarcoma subtype; thus, we used cell lines to validate the role of the RB-E2F pathway in regulating the prognostic gene signature. Ectopic RB resets the patterns of E2F regulated gene expression in cells derived from tumors with worse clinical outcomes (molecular phenotype 2) to those comparable with those observed in cells derived from tumors with less aggressive outcomes (molecular phenotype 1), providing a functional association between RB-E2F dysfunction and altered gene expression in osteosarcoma. DNA methyltransferase and histone deacetylase inhibitors similarly reset the transcriptional state of the molecular phenotype 2 cells from a state associated with RB deficiency to one seen with RB sufficiency. Our data indicate that deregulation of RB-E2F pathway alters the epigenetic landscape and biological behavior of osteosarcoma. PMID:26378234

Accelerated Stem Growth Rates and Improved Fiber Properties of Loblolly Pine: Functional Analysis Of CyclinD from Pinus taeda

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

Dr. John Cairney, School of Biology and Institute of Paper Science and Technology @ Georgia Tech, Georgia Institute of Technology; Dr. Gary Peter, University of Florida; Dr. Ulrika Egertsdotter, Dept. of Forestry, Virgina Tech

A sustained supply of low-cost, high quality raw materials is essential for the future success of the U.S. forest products industry. To maximize stem (trunk) growth, a fundamental understanding of the molecular mechanisms that regulate cell divisions within the cambial meristem is essential. We hypothesize that auxin levels within the cambial meristem regulate cyclin gene expression and this in turn controls cell cycle progression as occurs in all eukaryotic cells. Work with model plant species has shown that ectopic overexpression of cyclins promotes cell division thereby increasing root growth > five times. We intended to test whether ectopic overexpression ofmore » cambial cyclins in the cambial zone of loblolly pine also promotes cell division rates that enhance stem growth rates. Results generated in model annual angiosperm systems cannot be reliably extrapolated to perennial gymnosperms, thus while the generation and development of transgenic pine is time consuming, this is the necessary approach for meaningful data. We succeeded in isolating a cyclin D gene and Clustal analysis to the Arabidopsis cyclin D gene family indicates that it is more closely related to cyclin D2 than D1 or D3 Using this gene as a probe we observed a small stimulation of cyclin D expression in somatic embryo culture upon addition of auxin. We hypothesized that trees with more cells in the vascular cambial and expansion zones will have higher cyclin mRNA levels. We demonstrated that in trees under compressive stress where the rates of cambial divisions are increased on the underside of the stem relative to the top or opposite side, there was a 20 fold increase in the level of PtcyclinD1 mRNA on the compressed side of the stem relative to the opposite. This suggests that higher secondary growth rates correlate with PtcyclinD1 expression. We showed that larger diameter trees show more growth during each year and that the increased growth in loblolly pine trees correlates with more cell divisions in the cambial meristem as expected. We isolated a promoter from a cambial specific gene and commenced development of transformation protocols for loblolly pine. Since our results show that cyclin D expression correlates with increased growth we continued with experiments to demonstrate the effect of cyclin overexpression upon tree growth. Vectors which constitutively express the cyclin D cDNA were constructed and transformed into a transgenic pine system through the collaboration with Forest Research, New Zealand. The transformation system for Pinus radiata is well established and we hoped to gain phenotypic information in a closely related pine, rather than await development of a robust loblolly pine transformation method. Transformation experiments were conducted by a biolistic method developed at Forest Research, NZ. A total of 78 transgenic embryogenic lines were generated and bulked up with a good representation of transgenic lines per construct. Transformed calli were originally identified by resistance to the antibiotic Geneticin contained in the medium. The transgenic nature of the selected lines was subsequently confirmed using histochemical GUS staining. To date, 10 out of 13 selected transgenic lines have produced embryos and we are currently harvesting the first transgenic plantlets. At present time 22 of those plantlets have been moved to GMO facilities. We will soon develop a strategy for assessing potential phenotypic differences between the transclones and non-transformed controls. Transgenic plants are being grown to a stage (approx. 1 year) when meaningful phenotypic evaluation can be conducted. The recent availability of 10,000 element loblolly pine cDNA microarray will permit the evaluation of cyclinD overexpression upon gene expression in transgenic Pinus.« less

Fine regulation of RhoA and Rock is required for skeletal muscle differentiation.

PubMed

Castellani, Loriana; Salvati, Erica; Alemà, Stefano; Falcone, Germana

2006-06-02

The RhoA GTPase controls a variety of cell functions such as cell motility, cell growth, and gene expression. Previous studies suggested that RhoA mediates signaling inputs that promote skeletal myogenic differentiation. We show here that levels and activity of RhoA protein are down-regulated in both primary avian myoblasts and mouse satellite cells undergoing differentiation, suggesting that a fine regulation of this GTPase is required. In addition, ectopic expression of activated RhoA in primary quail myocytes, but not in mouse myocytes, inhibits accumulation of muscle-specific proteins and cell fusion. By disrupting RhoA signaling with specific inhibitors, we have shown that this GTPase, although required for cell identity in proliferating myoblasts, is not essential for commitment to terminal differentiation and muscle gene expression. Ectopic expression of an activated form of its downstream effector, Rock, impairs differentiation of both avian and mouse myoblasts. Conversely, Rock inhibition with specific inhibitors and small interfering RNA-mediated gene silencing leads to accelerated progression in the lineage and enhanced cell fusion, underscoring a negative regulatory function of Rock in myogenesis. Finally, we have reported that Rock acts independently from RhoA in preventing myoblast exit from the cell cycle and commitment to differentiation and may receive signaling inputs from Raf-1 kinase.

Cardiac Fibroblasts Adopt Osteogenic Fates and Can Be Targeted to Attenuate Pathological Heart Calcification.

PubMed

Pillai, Indulekha C L; Li, Shen; Romay, Milagros; Lam, Larry; Lu, Yan; Huang, Jie; Dillard, Nathaniel; Zemanova, Marketa; Rubbi, Liudmilla; Wang, Yibin; Lee, Jason; Xia, Ming; Liang, Owen; Xie, Ya-Hong; Pellegrini, Matteo; Lusis, Aldons J; Deb, Arjun

2017-02-02

Mammalian tissues calcify with age and injury. Analogous to bone formation, osteogenic cells are thought to be recruited to the affected tissue and induce mineralization. In the heart, calcification of cardiac muscle leads to conduction system disturbances and is one of the most common pathologies underlying heart blocks. However the cell identity and mechanisms contributing to pathological heart muscle calcification remain unknown. Using lineage tracing, murine models of heart calcification and in vivo transplantation assays, we show that cardiac fibroblasts (CFs) adopt an osteoblast cell-like fate and contribute directly to heart muscle calcification. Small-molecule inhibition of ENPP1, an enzyme that is induced upon injury and regulates bone mineralization, significantly attenuated cardiac calcification. Inhibitors of bone mineralization completely prevented ectopic cardiac calcification and improved post injury heart function. Taken together, these findings highlight the plasticity of fibroblasts in contributing to ectopic calcification and identify pharmacological targets for therapeutic development. Copyright © 2017 Elsevier Inc. All rights reserved.

Two FGFRL-Wnt circuits organize the planarian anteroposterior axis.

PubMed

Scimone, M Lucila; Cote, Lauren E; Rogers, Travis; Reddien, Peter W

2016-04-11

How positional information instructs adult tissue maintenance is poorly understood. Planarians undergo whole-body regeneration and tissue turnover, providing a model for adult positional information studies. Genes encoding secreted and transmembrane components of multiple developmental pathways are predominantly expressed in planarian muscle cells. Several of these genes regulate regional identity, consistent with muscle harboring positional information. Here, single-cell RNA-sequencing of 115 muscle cells from distinct anterior-posterior regions identified 44 regionally expressed genes, including multiple Wnt and ndk/FGF receptor-like (ndl/FGFRL) genes. Two distinct FGFRL-Wnt circuits, involving juxtaposed anterior FGFRL and posterior Wnt expression domains, controlled planarian head and trunk patterning. ndl-3 and wntP-2 inhibition expanded the trunk, forming ectopic mouths and secondary pharynges, which independently extended and ingested food. fz5/8-4 inhibition, like that of ndk and wntA, caused posterior brain expansion and ectopic eye formation. Our results suggest that FGFRL-Wnt circuits operate within a body-wide coordinate system to control adult axial positioning.

The adaptor protein Cindr regulates JNK activity to maintain epithelial sheet integrity.

PubMed

Yasin, Hannah W R; van Rensburg, Samuel H; Feiler, Christina E; Johnson, Ruth I

2016-02-15

Epithelia are essential barrier tissues that must be appropriately maintained for their correct function. To achieve this a plethora of protein interactions regulate epithelial cell number, structure and adhesion, and differentiation. Here we show that Cindr (the Drosophila Cin85 and Cd2ap ortholog) is required to maintain epithelial integrity. Reducing Cindr triggered cell delamination and movement. Most delaminating cells died. These behaviors were consistent with JNK activation previously associated with loss of epithelial integrity in response to ectopic oncogene activity. We confirmed a novel interaction between Cindr and Drosophila JNK (dJNK), which when perturbed caused inappropriate JNK signaling. Genetically reducing JNK signaling activity suppressed the effects of reducing Cindr. Furthermore, ectopic JNK signaling phenocopied loss of Cindr and was partially rescued by concomitant cindr over-expression. Thus, correct Cindr-dJNK stoichiometry is essential to maintain epithelial integrity and disturbing this balance may contribute to the pathogenesis of disease states, including cancer. Copyright © 2016 Elsevier Inc. All rights reserved.

Ectopic Pregnancy

MedlinePlus

... Safe Videos for Educators Search English Español Ectopic Pregnancy KidsHealth / For Parents / Ectopic Pregnancy What's in this ... loss) lower back pain What Causes an Ectopic Pregnancy? An ectopic pregnancy usually happens because a fertilized ...

Steroid signaling in mature follicles is important for Drosophila ovulation

PubMed Central

Knapp, Elizabeth

2017-01-01

Although ecdysteroid signaling regulates multiple steps in oogenesis, it is not known whether it regulates Drosophila ovulation, a process involving a matrix metalloproteinase-dependent follicle rupture. In this study, we demonstrated that ecdysteroid signaling is operating in mature follicle cells to control ovulation. Moreover, knocking down shade (shd), encoding the monooxygenase that converts ecdysone (E) to the more active 20-hydroxyecdysone (20E), specifically in mature follicle cells, blocked follicle rupture, which was rescued by ectopic expression of shd or exogenous 20E. In addition, disruption of the Ecdysone receptor (EcR) in mature follicle cells mimicked shd-knockdown defects, which were reversed by ectopic expression of EcR.B2 but not by EcR.A or EcR.B1 isoforms. Furthermore, we showed that ecdysteroid signaling is essential for the proper activation of matrix metalloproteinase 2 (Mmp2) for follicle rupture. Our data strongly suggest that 20E produced in follicle cells before ovulation activates EcR.B2 to prime mature follicles to be responsive to neuronal ovulatory stimuli, thus providing mechanistic insights into steroid signaling in Drosophila ovulation. PMID:28069934

Nucleotides released by apoptotic cells act as a find-me signal to promote phagocytic clearance.

PubMed

Elliott, Michael R; Chekeni, Faraaz B; Trampont, Paul C; Lazarowski, Eduardo R; Kadl, Alexandra; Walk, Scott F; Park, Daeho; Woodson, Robin I; Ostankovich, Marina; Sharma, Poonam; Lysiak, Jeffrey J; Harden, T Kendall; Leitinger, Norbert; Ravichandran, Kodi S

2009-09-10

Phagocytic removal of apoptotic cells occurs efficiently in vivo such that even in tissues with significant apoptosis, very few apoptotic cells are detectable. This is thought to be due to the release of 'find-me' signals by apoptotic cells that recruit motile phagocytes such as monocytes, macrophages and dendritic cells, leading to the prompt clearance of the dying cells. However, the identity and in vivo relevance of such find-me signals are not well understood. Here, through several lines of evidence, we identify extracellular nucleotides as a critical apoptotic cell find-me signal. We demonstrate the caspase-dependent release of ATP and UTP (in equimolar quantities) during the early stages of apoptosis by primary thymocytes and cell lines. Purified nucleotides at these concentrations were sufficient to induce monocyte recruitment comparable to that of apoptotic cell supernatants. Enzymatic removal of ATP and UTP (by apyrase or the expression of ectopic CD39) abrogated the ability of apoptotic cell supernatants to recruit monocytes in vitro and in vivo. We then identified the ATP/UTP receptor P2Y(2) as a critical sensor of nucleotides released by apoptotic cells using RNA interference-mediated depletion studies in monocytes, and macrophages from P2Y(2)-null mice. The relevance of nucleotides in apoptotic cell clearance in vivo was revealed by two approaches. First, in a murine air-pouch model, apoptotic cell supernatants induced a threefold greater recruitment of monocytes and macrophages than supernatants from healthy cells did; this recruitment was abolished by depletion of nucleotides and was significantly decreased in P2Y(2)(-/-) (also known as P2ry2(-/-)) mice. Second, clearance of apoptotic thymocytes was significantly impaired by either depletion of nucleotides or interference with P2Y receptor function (by pharmacological inhibition or in P2Y(2)(-/-) mice). These results identify nucleotides as a critical find-me cue released by apoptotic cells to promote P2Y(2)-dependent recruitment of phagocytes, and provide evidence for a clear relationship between a find-me signal and efficient corpse clearance in vivo.

Ectopic lignification in primary cellulose-deficient cell walls of maize cell suspension cultures.

PubMed

Mélida, Hugo; Largo-Gosens, Asier; Novo-Uzal, Esther; Santiago, Rogelio; Pomar, Federico; García, Pedro; García-Angulo, Penélope; Acebes, José Luis; Álvarez, Jesús; Encina, Antonio

2015-04-01

Maize (Zea mays L.) suspension-cultured cells with up to 70% less cellulose were obtained by stepwise habituation to dichlobenil (DCB), a cellulose biosynthesis inhibitor. Cellulose deficiency was accompanied by marked changes in cell wall matrix polysaccharides and phenolics as revealed by Fourier transform infrared (FTIR) spectroscopy. Cell wall compositional analysis indicated that the cellulose-deficient cell walls showed an enhancement of highly branched and cross-linked arabinoxylans, as well as an increased content in ferulic acid, diferulates and p-coumaric acid, and the presence of a polymer that stained positive for phloroglucinol. In accordance with this, cellulose-deficient cell walls showed a fivefold increase in Klason-type lignin. Thioacidolysis/GC-MS analysis of cellulose-deficient cell walls indicated the presence of a lignin-like polymer with a Syringyl/Guaiacyl ratio of 1.45, which differed from the sensu stricto stress-related lignin that arose in response to short-term DCB-treatments. Gene expression analysis of these cells indicated an overexpression of genes specific for the biosynthesis of monolignol units of lignin. A study of stress signaling pathways revealed an overexpression of some of the jasmonate signaling pathway genes, which might trigger ectopic lignification in response to cell wall integrity disruptions. In summary, the structural plasticity of primary cell walls is proven, since a lignification process is possible in response to cellulose impoverishment. © 2015 Institute of Botany, Chinese Academy of Sciences.

Mononuclear Cells from Dedifferentiation of Mouse Myotubes display Remarkable Regenerative Capability

PubMed Central

Yang, Zhong; Liu, Qiang; Mannix, Robert J.; Xu, Xiaoyin; Li, Hongli; Ma, Zhiyuan; Ingber, Donald E.; Allen, Paul D.; Wang, Yaming

2015-01-01

Certain lower organisms achieve organ regeneration by reverting differentiated cells into tissue-specific progenitors that re-enter embryonic programs. During muscle regeneration in the urodele amphibian, post-mitotic multinucleated skeletal myofibers transform into mononucleated proliferating cells upon injury, and a transcription factor-msx1 plays a role in their reprograming. Whether this powerful regeneration strategy can be leveraged in mammals remains unknown, as it has not been demonstrated that the dedifferentiated progenitor cells arising from muscle cells overexpressing Msx1 are lineage-specific and possess the same potent regenerative capability as their amphibian counterparts. Here we show that ectopic expression of Msx1 reprograms post-mitotic, multinucleated, primary mouse myotubes to become proliferating mononuclear cells. These dedifferentiated cells reactivate genes expressed by embryonic muscle progenitor cells and generate only muscle tissue in vivo both in an ectopic location and inside existing muscle. More importantly, distinct from adult muscle satellite cells, these cells appear both to fuse with existing fibers and to regenerate myofibers in a robust and time-dependent manner. Upon transplantation into a degenerating muscle, these dedifferentiated cells generated a large number of myofibers that increased over time and replenished almost half of the cross-sectional area of the muscle in only 12 weeks. Our study demonstrates that mammals can harness a muscle regeneration strategy used by lower organisms when the same molecular pathway is activated. PMID:24916688

miR-200b and miR-200c as prognostic factors and mediators of gastric cancer cell progression.

PubMed

Tang, Hailin; Deng, Min; Tang, Yunyun; Xie, Xinhua; Guo, Jiaoli; Kong, Yanan; Ye, Feng; Su, Qi; Xie, Xiaoming

2013-10-15

The purpose of this study was to investigate the clinicopathologic significance and potential role of miR-200b and miR-200c in the development and progression of gastric cancer. We examined miR-200b and miR-200c expression in 36 paired normal and stomach tumor specimens, as well as gastric cancer cell lines, by quantitative real-time PCR. In addition, miR-200b and miR-200c were detected by ISH using gastric cancer tissue microarrays, and the association between miR-200b and miR-200c levels and clinicopathologic factors and prognosis were analyzed. A luciferase assay was conducted for target evaluation. The functional effects of miR-200b and miR-200c on gastric cancer cells were validated by a cell proliferation assay and cell invasion and migration assays. miR-200b and miR-200c were downregulated in the gastric cancer specimens and cell lines tested. miR-200b and miR-200c levels were significantly correlated with the clinical stage, T stage, lymph node metastasis, and survival of patients. Ectopic expression of miR-200b and miR-200c impaired cell growth and invasion. In addition, when overexpressed, miR-200b and miR-200c commonly directly targeted DNMT3A, DNMT3B, and SP1 (a transactivator of the DNMT1 gene), which resulted in marked reduction of the expression of DNA methyltransferases DNMT1, DNMT3A, and DNMT3B at the protein level. This effect, in turn, led to a decrease in global DNA methylation and reexpression of p16, RASS1A1, and E-cadherin via promoter DNA hypomethylation. Our findings suggest that miR-200b and miR-200c, as valuable markers of gastric cancer prognosis, may be a promising approach to human gastric cancer treatment. ©2013 AACR.

A synthetic cGMP-sensitive gene switch providing Viagra(®)-controlled gene expression in mammalian cells and mice.

PubMed

Kim, Taeuk; Folcher, Marc; Charpin-El Hamri, Ghislaine; Fussenegger, Martin

2015-05-01

Cyclic guanosine monophosphate (cGMP) is a universal second messenger that is synthesized from guanosine triphosphate (GTP) by guanylyl cyclases (GCs) and hydrolyzed into guanosine monophosphate (GMP) by phosphodiesterases (PDEs). Small-molecule drugs that induce high cGMP levels in specialized tissues by boosting GC activity or inhibiting PDE activity have become the predominant treatment strategy for a wide range of medical conditions, including congestive heart failure, pulmonary hypertension, atherosclerosis-based claudication and erectile dysfunction. By fusing the cGMP receptor protein (CRP) of Rhodospirillum centenum to the Herpes simplex-derived transactivation domain VP16, we created a novel synthetic mammalian cGMP-sensing transcription factor (GTA) that activates synthetic promoters (PGTA) containing newly identified GTA-specific operator sites in a concentration-dependent manner. In cell lines expressing endogenous natriuretic peptide receptor A (NPR-A) (HeLa), GTA/PGTA-driven transgene expression was induced by B-type natriuretic peptide (BNP; Nesiritide(®)) in a concentration-dependent manner, which activated NPR-A׳s intracellular GC domain and triggered a corresponding cGMP surge. Ectopic expression of NPR-A in NPR-A-negative cell lines (HEK-293T) produced high cGMP levels and mediated maximum GTA/PGTA-driven transgene expression, which was suppressed by co-expression of PDEs (PDE-3A, PDE-5A and PDE-9A) and was re-triggered by the corresponding PDE inhibitor drugs (Pletal(®), Perfan(®), Primacor(®) (PDE-3A), Viagra(®), Levitra(®), Cialis(®) (PDE-5A) and BAY73-6691 (PDE-9A)). Mice implanted with microencapsulated designer cells co-expressing the GTA/PGTA device with NPR-A and PDE-5A showed control of blood SEAP levels through administration of sildenafil (Viagra(®)). Designer cells engineered for PDE inhibitor-modulated transgene expression may provide a cell-based PDE-targeting drug discovery platform and enable drug-adjusted gene- and cell-based therapies. Copyright © 2015 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

LRIG1, a 3p tumor suppressor, represses EGFR signaling and is a novel epigenetic silenced gene in colorectal cancer

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

Kou, Changhua, E-mail: chkoukou@hotmail.com; Zhou, Tian; Han, Xilin

2015-08-21

Downregulation of LRIG1 was found in many types of cancer. However, data concerning the possible mechanism of LRIG1 reduction in cancers were not reported yet. To analyze the regulation and function of LRIG1 in colorectal cancer (CRC), 6 cell lines, 46 paired tissues from primary CRC cases were employed in this study. In CRC cell lines, under-expression of LRIG1 was correlated with promoter region hypermethylation, and restoration of LRIG1 was induced by 5-Aza-2'-deoxyazacytidine treatment. Subsequently, we ectopically expressed LRIG1 in LRIG1 low-expressing HCT-116 cells and suppressed LRIG1 in LRIG1 high-expressing LoVo cells. We found that over-expression of LRIG1 inhibits cellmore » proliferation and colony formation and tumor growth, while knockdown of LRIG1 promotes cell proliferation and colony formation. Decreased and increased EGFR/AKT signaling pathway may partially explain the lower and higher rates of proliferation in CRC cells transfected with LRIG1 cDNA or shRNA. In clinical samples, we compared the methylation, mRNA and protein expression of LRIG1 in samples of CRC tissues. A significant increase in LRIG1 methylation was identified in CRC specimens compared to adjacent normal tissues and that it was negatively correlated with its mRNA and protein expression. In conclusion, LRIG1 is frequently methylated in human CRC and consequent mRNA and protein downregulation may contribute to tumor growth by activating EGFR/AKT signaling. - Highlights: • Promoter methylation of LRIG1 occurred in colorectal cancer cells and tumors. • Restoration of LRIG1 inhibits tumor growth in vitro and in vivo. • Overexpression or knockdown of LRIG1 regulates EGFR/AKT and downstream apoptosis. • Methylation of LRIG1 correlates with its mRNA and protein downregulation. • LRIG1 was firstly identified as an epigenetic target in cancer.« less

Fluorescent genetic barcoding in mammalian cells for enhanced multiplexing capabilities in flow cytometry.

PubMed

Smurthwaite, Cameron A; Hilton, Brett J; O'Hanlon, Ryan; Stolp, Zachary D; Hancock, Bryan M; Abbadessa, Darin; Stotland, Aleksandr; Sklar, Larry A; Wolkowicz, Roland

2014-01-01

The discovery of the green fluorescent protein from Aequorea victoria has revolutionized the field of cell and molecular biology. Since its discovery a growing panel of fluorescent proteins, fluorophores and fluorescent-coupled staining methodologies, have expanded the analytical capabilities of flow cytometry. Here, we exploit the power of genetic engineering to barcode individual cells with genes encoding fluorescent proteins. For genetic engineering, we utilize retroviral technology, which allows for the expression of ectopic genetic information in a stable manner in mammalian cells. We have genetically barcoded both adherent and nonadherent cells with different fluorescent proteins. Multiplexing power was increased by combining both the number of distinct fluorescent proteins, and the fluorescence intensity in each channel. Moreover, retroviral expression has proven to be stable for at least a 6-month period, which is critical for applications such as biological screens. We have shown the applicability of fluorescent barcoded multiplexing to cell-based assays that rely themselves on genetic barcoding, or on classical staining protocols. Fluorescent genetic barcoding gives the cell an inherited characteristic that distinguishes it from its counterpart. Once cell lines are developed, no further manipulation or staining is required, decreasing time, nonspecific background associated with staining protocols, and cost. The increasing number of discovered and/or engineered fluorescent proteins with unique absorbance/emission spectra, combined with the growing number of detection devices and lasers, increases multiplexing versatility, making fluorescent genetic barcoding a powerful tool for flow cytometry-based analysis. © 2013 International Society for Advancement of Cytometry.

Telomeric repeat-containing RNA/G-quadruplex-forming sequences cause genome-wide alteration of gene expression in human cancer cells in vivo.

PubMed

Hirashima, Kyotaro; Seimiya, Hiroyuki

2015-02-27

Telomere erosion causes cell mortality, suggesting that longer telomeres enable more cell divisions. In telomerase-positive human cancer cells, however, telomeres are often kept shorter than those of surrounding normal tissues. Recently, we showed that cancer cell telomere elongation represses innate immune genes and promotes their differentiation in vivo. This implies that short telomeres contribute to cancer malignancy, but it is unclear how such genetic repression is caused by elongated telomeres. Here, we report that telomeric repeat-containing RNA (TERRA) induces a genome-wide alteration of gene expression in telomere-elongated cancer cells. Using three different cell lines, we found that telomere elongation up-regulates TERRA signal and down-regulates innate immune genes such as STAT1, ISG15 and OAS3 in vivo. Ectopic TERRA oligonucleotides repressed these genes even in cells with short telomeres under three-dimensional culture conditions. This appeared to occur from the action of G-quadruplexes (G4) in TERRA, because control oligonucleotides had no effect and a nontelomeric G4-forming oligonucleotide phenocopied the TERRA oligonucleotide. Telomere elongation and G4-forming oligonucleotides showed similar gene expression signatures. Most of the commonly suppressed genes were involved in the innate immune system and were up-regulated in various cancers. We propose that TERRA G4 counteracts cancer malignancy by suppressing innate immune genes. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

TET1 promotes cisplatin-resistance via demethylating the vimentin promoter in ovarian cancer.

PubMed

Han, Xi; Zhou, Yuanyuan; You, Yuanyi; Lu, Jiaojiao; Wang, Lijie; Hou, Huilian; Li, Jing; Chen, Wei; Zhao, Le; Li, Xu

2017-04-01

The development of chemo-resistance impairs the outcome of the first line platinum-based chemotherapies for ovarian cancer. Deregulation of DNA methylation/demethylation provides a critical mechanism for the occurrence of chemo-resistance. The ten-eleven translocation (TET) family of dioxygenases including TET1/2/3 plays an important part in DNA demethylation, but their roles in cisplatin resistance have not been elucidated. Using cisplatin-sensitive and cisplatin-resistant ovarian cancer cell models, we found that TET1 was significantly upregulated in cisplatin-resistant CP70 cells compared with that in cisplatin-sensitive A2780 cells. Ectopic expression of TET1 in A2780 cells promoted cisplatin resistance and decreased cytotoxicity induced by cisplatin, while inhibition of TET1 by siRNA transfection in CP70 cells attenuated cisplatin resistance and enhanced cytotoxicity of cisplatin. Increased TET1 induced re-expression of vimentin through active DNA demethylation, and cause partial epithelial-to-mesenchymal (EMT) in A2780 cells. Contrarily, knocking down of TET1 in CP70 cells reduced vimentin expression and reversed EMT process. Immunohistochemical analysis of TET1 in human ovarian cancer tissues revealed that TET1 existed in nucleus and cytoplasm in ovarian cancer tissues. And the expression of nuclear TET1 was positively correlated with residual tumor and chemotherapeutic response. Thus, TET1 expression causes resistance to cisplatin and one of the targets of TET1 action is vimentin in ovarian cancer. © 2017 International Federation for Cell Biology.

Telomerase Activity Impacts on Epstein-Barr Virus Infection of AGS Cells

PubMed Central

Rac, Jürgen; Haas, Florian; Schumacher, Andrina; Middeldorp, Jaap M.; Delecluse, Henri-Jacques; Speck, Roberto F.

2015-01-01

The Epstein-Barr virus (EBV) is transmitted from host-to-host via saliva and is associated with epithelial malignancies including nasopharyngeal carcinoma (NPC) and some forms of gastric carcinoma (GC). Nevertheless, EBV does not transform epithelial cells in vitro where it is rapidly lost from infected primary epithelial cells or epithelial tumor cells. Long-term infection by EBV, however, can be established in hTERT-immortalized nasopharyngeal epithelial cells. Here, we hypothesized that increased telomerase activity in epithelial cells enhances their susceptibility to infection by EBV. Using HONE-1, AGS and HEK293 cells we generated epithelial model cell lines with increased or suppressed telomerase activity by stable ectopic expression of hTERT or of a catalytically inactive, dominant negative hTERT mutant. Infection experiments with recombinant prototypic EBV (rB95.8), recombinant NPC EBV (rM81) with increased epithelial cell tropism compared to B95.8, or recombinant B95.8 EBV with BZLF1-knockout that is not able to undergo lytic replication, revealed that infection frequencies positively correlate with telomerase activity in AGS cells but also partly depend on the cellular background. AGS cells with increased telomerase activity showed increased expression mainly of latent EBV genes, suggesting that increased telomerase activity directly acts on the EBV infection of epithelial cells by facilitating latent EBV gene expression early upon virus inoculation. Thus, our results indicate that infection of epithelial cells by EBV is a very selective process involving, among others, telomerase activity and cellular background to allow for optimized host-to-host transmission via saliva. PMID:25856387

DDX60L Is an Interferon-Stimulated Gene Product Restricting Hepatitis C Virus Replication in Cell Culture

PubMed Central

Grünvogel, Oliver; Esser-Nobis, Katharina; Reustle, Anna; Schult, Philipp; Müller, Birthe; Metz, Philippe; Trippler, Martin; Windisch, Marc P.; Frese, Michael; Binder, Marco; Fackler, Oliver; Bartenschlager, Ralf; Ruggieri, Alessia

2015-01-01

ABSTRACT All major types of interferon (IFN) efficiently inhibit hepatitis C virus (HCV) replication in vitro and in vivo. Remarkably, HCV replication is not sensitive to IFN-γ in the hepatoma cell line Huh6, despite an intact signaling pathway. We performed transcriptome analyses between Huh6 and Huh-7 cells to identify effector genes of the IFN-γ response and thereby identified the DExD/H box helicase DEAD box polypeptide 60-like (DDX60L) as a restriction factor of HCV replication. DDX60L and its homolog DEAD box polypeptide 60 (DDX60) were both induced upon viral infection and IFN treatment in primary human hepatocytes. However, exclusively DDX60L knockdown increased HCV replication in Huh-7 cells and rescued HCV replication from type II IFN as well as type I and III IFN treatment, suggesting that DDX60L is an important effector protein of the innate immune response against HCV. In contrast, we found no impact of DDX60L on replication of hepatitis A virus. DDX60L protein was detectable only upon strong ectopic overexpression, displayed a broad cytoplasmic distribution, but caused cytopathic effects under these conditions. DDX60L knockdown did not alter interferon-stimulated gene (ISG) induction after IFN treatment but inhibited HCV replication upon ectopic expression, suggesting that it is a direct effector of the innate immune response. It most likely inhibits viral RNA replication, since we found neither impact of DDX60L on translation or stability of HCV subgenomic replicons nor additional impact on assembly of infectious virus. Similar to DDX60, DDX60L had a moderate impact on RIG-I dependent activation of innate immunity, suggesting additional functions in the sensing of viral RNA. IMPORTANCE Interferons induce a plethora of interferon-stimulated genes (ISGs), which are our first line of defense against viral infections. In addition, IFNs have been used in antiviral therapy, in particular against the human pathogen hepatitis C virus (HCV); still, their mechanism of action is not well understood, since diverse, overlapping sets of antagonistic effector ISGs target viruses with different biologies. Our work identifies DDX60L as a novel factor that inhibits replication of HCV. DDX60L expression is regulated similarly to that of its homolog DDX60, but our data suggest that it has distinct functions, since we found no contribution of DDX60 in combatting HCV replication. The identification of novel components of the innate immune response contributes to a comprehensive understanding of the complex mechanisms governing antiviral defense. PMID:26269178

Neuropilin-1 Is Expressed on Lymphoid Tissue Residing LTi-like Group 3 Innate Lymphoid Cells and Associated with Ectopic Lymphoid Aggregates.

PubMed

Shikhagaie, Medya Mara; Björklund, Åsa K; Mjösberg, Jenny; Erjefält, Jonas S; Cornelissen, Anne S; Ros, Xavier Romero; Bal, Suzanne M; Koning, Jasper J; Mebius, Reina E; Mori, Michiko; Bruchard, Melanie; Blom, Bianca; Spits, Hergen

2017-02-14

Here, we characterize a subset of ILC3s that express Neuropilin1 (NRP1) and are present in lymphoid tissues, but not in the peripheral blood or skin. NRP1 + group 3 innate lymphoid cells (ILC3s) display in vitro lymphoid tissue inducer (LTi) activity. In agreement with this, NRP1 + ILC3s are mainly located in proximity to high endothelial venules (HEVs) and express cell surface molecules involved in lymphocyte migration in secondary lymphoid tissues via HEVs. NRP1 was also expressed on mouse fetal LTi cells, indicating that NRP1 is a conserved marker for LTi cells. Human NRP1 + ILC3s are primed cells because they express CD45RO and produce higher amounts of cytokines than NRP1 - cells, which express CD45RA. The NRP1 ligand vascular endothelial growth factor A (VEGF-A) served as a chemotactic factor for NRP1 + ILC3s. NRP1 + ILC3s are present in lung tissues from smokers and patients with chronic obstructive pulmonary disease, suggesting a role in angiogenesis and/or the initiation of ectopic pulmonary lymphoid aggregates. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

A novel E2 box-GATA element modulates Cdc6 transcription during human cells polyploidization

PubMed Central

Vilaboa, Nuria; Bermejo, Rodrigo; Martinez, Pilar; Bornstein, Rafael; Calés, Carmela

2004-01-01

Cdc6 is a key regulator of the strict alternation of S and M phases during the mitotic cell cycle. In mammalian and plant cells that physiologically become polyploid, cdc6 is transcriptionally and post-translationally regulated. We have recently reported that Cdc6 levels are maintained in megakaryoblastic HEL cells, but severely downregulated by ectopic expression of transcriptional repressor Drosophila melanogaster escargot. Here, we show that cdc6 promoter activity is upregulated during megakaryocytic differentiation of HEL endoreplicating cells, and that Escargot interferes with such activation. Transactivation experiments showed that a 1.7 kb region located at 2800 upstream cdc6 transcription initiation site behaved as a potent enhancer in endoreplicating cells only. This activity was mainly dependent on a novel cis-regulatory element composed by an E2 box overlapping a GATA motif. Ectopic Escargot could bind this regulatory element in vitro and endogenous GATA-1 and E2A formed specific complexes in megakaryoblastic cells as well as in primary megakaryocytes. Chromatin Immunoprecipitation analysis revealed that both transcription factors were occupying the E2 box/GATA site in vivo. Altogether, these data suggest that cdc6 expression could be actively maintained during megakaryocytic differentiation through transcriptional mechanisms involving specific cis- and trans-regulatory elements. PMID:15590906

Dominant Suppression of β1 Integrin by Ectopic CD98-ICD Inhibits Hepatocellular Carcinoma Progression

PubMed Central

Wu, Bo; Zhou, Yang; Wang, Yu; Yang, Xiang-Min; Liu, Zhen-Yu; Li, Jiang-Hua; Feng, Fei; Chen, Zhi-Nan; Jiang, Jian-Li

2016-01-01

Hepatocellular carcinoma (HCC) is currently the third most common cause of cancer-related death in the Asia-Pacific region. Our previous work showed that knockdown of CD98 significantly inhibits malignant HCC cell phenotypes in vitro and in vivo. The level of CD98 in the membrane is tightly regulated to mediate complex processes associated with cell–cell communication and intracellular signaling. In addition, the intracellular domain of CD98 (CD98-ICD) seems to be of vital importance for recycling CD98 to the membrane after it is endocytosed. The intracellular and transmembrane domains of CD98 associate with β-integrins (primarily β1 but also β3), and this association is essential for CD98 mediation of integrin-like signaling and complements dominant suppression of β1-integrin. We speculated that isolated CD98-ICD would similarly suppress β1-integrin activation and inhibit the malignant behaviors of cancer cells. In particular, the exact role of CD98-ICD has not been studied independently in HCC. In this study, we found that ectopic expression of CD98-ICD inhibited the malignant phenotypes of HCC cells, and the mechanism possibly involves β1-integrin suppression. Moreover, the expression levels of CD98, β1-integrin-A (the activated form of β1-integrin) and Ki-67 were significantly increased in HCC tissues relative to those of normal liver tissues. Therefore, our preliminary study indicates that ectopic CD98-ICD has an inhibitory role in the malignant development of HCC, and shows that CD98-ICD acts as a dominant negative mutant of CD98 that attenuates β1-integrin activation. CD98-ICD may emerge as a promising candidate for antitumor treatment. PMID:27834933

To Assess the Association between Glucose Metabolism and Ectopic Lipid Content in Different Clinical Classifications of PCOS

PubMed Central

Göbl, Christian S.; Ott, Johannes; Bozkurt, Latife; Feichtinger, Michael; Rehmann, Victoria; Cserjan, Anna; Heinisch, Maike; Steinbrecher, Helmut; JustKukurova, Ivica; Tuskova, Radka; Leutner, Michael; Vytiska-Binstorfer, Elisabeth; Kurz, Christine; Weghofer, Andrea; Tura, Andrea; Egarter, Christian; Kautzky-Willer, Alexandra

2016-01-01

Aims There are emerging data indicating an association between PCOS (polycystic ovary syndrome) and metabolic derangements with potential impact on its clinical presentation. This study aims to evaluate the pathophysiological processes beyond PCOS with particular focus on carbohydrate metabolism, ectopic lipids and their possible interaction. Differences between the two established classifications of the disease should be additionally evaluated. Methods A metabolic characterization was performed in 53 untreated PCOS patients as well as 20 controls including an extended oral glucose tolerance test (OGTT, to assess insulin sensitivity, secretion and ß-cell function) in addition to a detailed examination of ectopic lipid content in muscle and liver by nuclear magnetic resonance spectroscopy. Results Women with PCOS classified by the original NIH 1990 definition showed a more adverse metabolic risk profile compared to women characterized by the additional Rotterdam 2003 phenotypes. Subtle metabolic derangements were observed in both subgroups, including altered shapes of OGTT curves, impaired insulin action and hyperinsulinemia due to increased secretion and attenuated hepatic extraction. No differences were observed for ectopic lipids between the groups. However, particularly hepatocellular lipid content was significantly related to clinical parameters of PCOS like whole body insulin sensitivity, dyslipidemia and free androgen index. Conclusions Subtle alterations in carbohydrate metabolism are present in both PCOS classifications, but more profound in subjects meeting the NIH 1990 criteria. Females with PCOS and controls did not differ in ectopic lipids, however, liver fat was tightly related to hyperandrogenism and an adverse metabolic risk profile. PMID:27505055

Brief Reports: Nfix Promotes Survival of Immature Hematopoietic Cells via Regulation of c-Mpl.

PubMed

Hall, Trent; Walker, Megan; Ganuza, Miguel; Holmfeldt, Per; Bordas, Marie; Kang, Guolian; Bi, Wenjian; Palmer, Lance E; Finkelstein, David; McKinney-Freeman, Shannon

2018-02-12

Hematopoietic stem and progenitor cells (HSPCs) are necessary for life-long blood production and replenishment of the hematopoietic system during stress. We recently reported that nuclear factor I/X (Nfix) promotes HSPC survival post-transplant. Here, we report that ectopic expression of Nfix in primary mouse HSPCs extends their ex vivo culture from about 20 to 40 days. HSPCs overexpressing Nfix display hypersensitivity to supportive cytokines and reduced apoptosis when subjected to cytokine deprivation relative to controls. Ectopic Nfix resulted in elevated levels of c-Mpl transcripts and cell surface protein on primary murine HSPCs as well as increased phosphorylation of STAT5, which is known to be activated down-stream of c-MPL. Blocking c-MPL signaling by removal of thrombopoietin or addition of a c-MPL neutralizing antibody negated the antiapoptotic effect of Nfix overexpression on cultured HSPCs. Furthermore, NFIX was capable of binding to and transcriptionally activating a proximal c-Mpl promoter fragment. In sum, these data suggest that NFIX-mediated upregulation of c-Mpl transcription can protect primitive hematopoietic cells from stress ex vivo. Stem Cells 2018. © AlphaMed Press 2018.

Interleukin-27 inhibits ectopic lymphoid-like structure development in early inflammatory arthritis

PubMed Central

Bombardieri, Michele; Greenhill, Claire J.; McLeod, Louise; Nerviani, Alessandra; Rocher-Ros, Vidalba; Cardus, Anna; Williams, Anwen S.; Pitzalis, Costantino; Jenkins, Brendan J.

2015-01-01

Ectopic lymphoid-like structures (ELSs) reminiscent of secondary lymphoid organs often develop at sites of chronic inflammation where they contribute to immune-mediated pathology. Through evaluation of synovial tissues from rheumatoid arthritis (RA) patients, we now show that low interleukin-27 (IL-27) expression corresponds with an increased incidence of ELS and gene signatures associated with their development and activity. The presence of synovial ELS was also noted in mice deficient in the IL-27 receptor (IL-27R) after the onset of inflammatory arthritis. Here, pathology was associated with increased synovial expression of pro-inflammatory cytokines, homeostatic chemokines, and transcriptional regulators linked with lymphoid neogenesis. In both clinical and experimental RA, synovial ELS coincided with the heightened local expression of cytokines and transcription factors of the Th17 and T follicular helper (Tfh) cell lineages, and included podoplanin-expressing T cells within lymphoid aggregates. IL-27 inhibited the differentiation of podoplanin-expressing Th17 cells, and an increased number of these cells were observed in IL-27R–deficient mice with inflammatory arthritis. Thus, IL-27 appears to negatively regulate ELS development in RA through control of effector T cells. These studies open new opportunities for patient stratification and treatment. PMID:26417004

New roles for Nanos in neural cell fate determination revealed by studies in a cnidarian.

PubMed

Kanska, Justyna; Frank, Uri

2013-07-15

Nanos is a pan-metazoan germline marker, important for germ cell development and maintenance. In flies, Nanos also acts in posterior and neural development, but these functions have not been demonstrated experimentally in other animals. Using the cnidarian Hydractinia we have uncovered novel roles for Nanos in neural cell fate determination. Ectopic expression of Nanos2 increased the numbers of embryonic stinging cell progenitors, but decreased the numbers of neurons. Downregulation of Nanos2 had the opposite effect. Furthermore, Nanos2 blocked maturation of committed, post-mitotic nematoblasts. Hence, Nanos2 acts as a switch between two differentiation pathways, increasing the numbers of nematoblasts at the expense of neuroblasts, but preventing nematocyte maturation. Nanos2 ectopic expression also caused patterning defects, but these were not associated with deregulation of Wnt signaling, showing that the basic anterior-posterior polarity remained intact, and suggesting that numerical imbalance between nematocytes and neurons might have caused these defects, affecting axial patterning only indirectly. We propose that the functions of Nanos in germ cells and in neural development are evolutionarily conserved, but its role in posterior patterning is an insect or arthropod innovation.

Is there still a role for reconstructive microsurgery in tubal infertility?

PubMed

Schippert, Cordula; Garcia-Rocha, Guillermo-José

2011-06-01

To review the current role of tubal reconstructive surgery in the era of assisted reproductive techniques (ARTs). After tubal reconstructive surgery, couples may have unlimited attempts to conceive naturally. Operative risks are low; the risk for ectopic pregnancy after surgery is 4-10%. ART is associated with a number of potential complications: severe ovarian hyperstimulation syndrome (0.25-2%), multiple pregnancies (up to 25%), a higher rate of major malformations and stillbirths, and ectopic pregnancy (1-13%). Birth rates following ART differ between 19 and 35%, depending on different laws governing the fertilization of a limited number of oocytes and the number of embryos transferred. Resterilization is a main indication for microsurgery with resulting pregnancy rates up to 84%. Salpingostomy and dense adhesiolysis have the lowest success rates (term pregnancy rates: 3-65%). Proximal tubal obstructions can be successfully treated by tubocornual anastomosis. Hydrosalpinges should be removed prior to in-vitro fertilization if they cannot be reconstructed. ART is recommended for patients older than 37-38 years, for women with severe tubal pathology, after repeated ectopic pregnancies, and in case of male infertility. Tubal reconstructive surgery still plays a role in infertility treatment. ART has not replaced microsurgery routinely as first-line treatment for tubal infertility.

[Breast abnormalities: a retrospective study of 208 patients].

PubMed

Famà, Fausto; Gioffrè Florio, Maria Antonietta; Villari, Santa Alessandra; Caruso, Rosario; Barresi, Valeria; Mazzei, Sergio; Pollicino, Andrea; Scarfò, Paola

2007-01-01

Ectopic breast tissue occurs in 0.4-6% of the general population. Usually, these tissues develop along the embryonic milk line but other sites are reported in the literature. Accessory breasts are commonly axillary and may undergo hormonal changes. Some pathologies of normally positioned breasts can occur in ectopic breast tissue, including carcinoma, and therefore require traditional senological flow-charts and imaging strategies. Supernumerary nipples are generally asymptomatic but may sometimes be associated with urological malformations. In our 10-year experience, 208 patients were observed (138 polythelia and 70 polymastia) and 159 surgical procedures were performed, 97 for supernumerary nipple excision and 67 for accessory breast ablation. Five neoplastic lesions and 25 fibrocystic mastopathies were detected in specimens; normal nipple or breast tissue was found in 129. In view of the potentially malignant transformation of accessory breasts, thorough physician evaluation is needed. Surgery is currently suggested in cases of suspected malignancy, in symptomatic cases and for cosmetic problems.

Suppression of MIM by microRNA-182 activates RhoA and promotes breast cancer metastasis.

PubMed

Lei, R; Tang, J; Zhuang, X; Deng, R; Li, G; Yu, J; Liang, Y; Xiao, J; Wang, H-Y; Yang, Q; Hu, G

2014-03-06

Breast cancer is the most common type of cancer among women worldwide, and metastasis represents the most devastating stage of the disease. Recent studies have revealed that microRNAs (miRNA) have critical roles to regulate cancer cell invasion and metastasis. Here we present evidence to show the role of miR-182 in breast cancer metastasis. miR-182 is upregulated in the malignant cell line variants of both human MCF10 and mouse 4T1 series. Ectopic expression of miR-182 enhanced breast cancer cell motility and invasiveness, whereas miR-182 inhibition resulted in opposite changes. In nude mice, miR-182 led to increased pulmonary colonization of cancer cells. We further demonstrated that miR-182 directly targets MIM (Missing in Metastasis), which suppresses metastasis by inhibiting ras homolog family member A (RhoA) activity and stress fiber formation in breast cancer cells. Restoring MIM expression completely blocked the pro-metastasis function of miR-182, while RhoA inhibition reversed the phenotypes of both miR-182 overexpression and MIM knockdown. In breast tumor samples, miR-182 induction is linked to downregulation of MIM, RhoA activation and poor prognosis. Hence, our data delineates the molecular pathway by which miR-182 promotes breast cancer invasion and metastasis, and may have important implication for the treatment of metastatic cancers.

Molecular and functional interactions between AKT and SOX2 in breast carcinoma

PubMed Central

Mir, Perihan; Konantz, Martina; Pereboom, Tamara C.; Paczulla, Anna M.; Merz, Britta; Fehm, Tanja; Perner, Sven; Rothfuss, Oliver C.; Kanz, Lothar; Schulze-Osthoff, Klaus; Lengerke, Claudia

2015-01-01

The transcription factor SOX2 is a key regulator of pluripotency in embryonic stem cells and plays important roles in early organogenesis. Recently, SOX2 expression was documented in various cancers and suggested as a cancer stem cell (CSC) marker. Here we identify the Ser/Thr-kinase AKT as an upstream regulator of SOX2 protein turnover in breast carcinoma (BC). SOX2 and pAKT are co-expressed and co-regulated in breast CSCs and depletion of either reduces clonogenicity. Ectopic SOX2 expression restores clonogenicity and in vivo tumorigenicity of AKT-inhibited cells, suggesting that SOX2 acts as a functional downstream AKT target. Mechanistically, we show that AKT physically interacts with the SOX2 protein to modulate its subcellular distribution. AKT kinase inhibition results in enhanced cytoplasmic retention of SOX2, presumably via impaired nuclear import, and in successive cytoplasmic proteasomal degradation of the protein. In line, blockade of either nuclear transport or proteasomal degradation rescues SOX2 expression in AKT-inhibited BC cells. Finally, AKT inhibitors efficiently suppress the growth of SOX2-expressing putative cancer stem cells, whereas conventional chemotherapeutics select for this population. Together, our results suggest the AKT/SOX2 molecular axis as a regulator of BC clonogenicity and AKT inhibitors as promising drugs for the treatment of SOX2-positive BC. PMID:26498353

Attenuated DNA damage repair by trichostatin A through BRCA1 suppression.

PubMed

Zhang, Yin; Carr, Theresa; Dimtchev, Alexandre; Zaer, Naghmeh; Dritschilo, Anatoly; Jung, Mira

2007-07-01

Recent studies have demonstrated that some histone deacetylase (HDAC) inhibitors enhance cellular radiation sensitivity. However, the underlying mechanism for such a radiosensitizing effect remains unexplored. Here we show evidence that treatment with the HDAC inhibitor trichostatin A (TSA) impairs radiation-induced repair of DNA damage. The effect of TSA on the kinetics of DNA damage repair was measured by performing the comet assay and gamma-H2AX focus analysis in radioresistant human squamous carcinoma cells (SQ-20B). TSA exposure increased the amount of radiation-induced DNA damage and slowed the repair kinetics. Gene expression profiling also revealed that a majority of the genes that control cell cycle, DNA replication and damage repair processes were down-regulated after TSA exposure, including BRCA1. The involvement of BRCA1 was further demonstrated by expressing ectopic wild-type BRCA1 in a BRCA1 null cell line (HCC-1937). TSA treatment enhanced radiation sensitivity of HCC-1937/wtBRCA1 clonal cells, which restored cellular radiosensitivity (D(0) = 1.63 Gy), to the control level (D(0) = 1.03 Gy). However, TSA had no effect on the level of radiosensitivity of BRCA1 null cells. Our data demonstrate for the first time that TSA treatment modulates the radiation-induced DNA damage repair process, in part by suppressing BRCA1 gene expression, suggesting that BRCA1 is one of molecular targets of TSA.

A single oncogenic enhancer rearrangement causes concomitant EVI1 and GATA2 deregulation in leukemia.

PubMed

Gröschel, Stefan; Sanders, Mathijs A; Hoogenboezem, Remco; de Wit, Elzo; Bouwman, Britta A M; Erpelinck, Claudia; van der Velden, Vincent H J; Havermans, Marije; Avellino, Roberto; van Lom, Kirsten; Rombouts, Elwin J; van Duin, Mark; Döhner, Konstanze; Beverloo, H Berna; Bradner, James E; Döhner, Hartmut; Löwenberg, Bob; Valk, Peter J M; Bindels, Eric M J; de Laat, Wouter; Delwel, Ruud

2014-04-10

Chromosomal rearrangements without gene fusions have been implicated in leukemogenesis by causing deregulation of proto-oncogenes via relocation of cryptic regulatory DNA elements. AML with inv(3)/t(3;3) is associated with aberrant expression of the stem-cell regulator EVI1. Applying functional genomics and genome-engineering, we demonstrate that both 3q rearrangements reposition a distal GATA2 enhancer to ectopically activate EVI1 and simultaneously confer GATA2 functional haploinsufficiency, previously identified as the cause of sporadic familial AML/MDS and MonoMac/Emberger syndromes. Genomic excision of the ectopic enhancer restored EVI1 silencing and led to growth inhibition and differentiation of AML cells, which could be replicated by pharmacologic BET inhibition. Our data show that structural rearrangements involving the chromosomal repositioning of a single enhancer can cause deregulation of two unrelated distal genes, with cancer as the outcome. Copyright © 2014 Elsevier Inc. All rights reserved.

Immunohistochemical analysis of an ectopic endometriosis in the uterine round ligament.

PubMed

Terada, Shinichi; Miyata, Yachiyo; Nakazawa, Hiroaki; Higashimori, Takamitsu; Arai, Takanari; Kikuchi, Yuji; Nozaki, Motohiro

2006-09-09

A rare case of the inguinal endometriosis was reported with immunohistochemical analysis. A 28-year-old woman had a thumb-sized tumor in the right groin for two years with a gradual increase in size and pain. An operation revealed an elastic hard tumor with an unclear margin and adhesion to the uterine round ligament. The histology showed irregular proliferation of the endometrial glands and stroma. The glandular epithelium stained weakly positive against CD125 antibody and the stromal matrix stained strongly positive against CD10 antibody. The nucleus in both the epithelial and stromal cells stained strongly positive against progesterone and estrogen receptor antibodies, and the cytoplasm in both types of cells stained moderately positive against COX-2 (cyclooxygenase-2) antibody. In conclusion, the combination of estrogen or progesterone receptor antibody for the nucleus and CD10 or COX-2 antibody for the cytoplasm could enhance the accuracy of diagnosis for ectopic endometriosis.

Ectopic decidua and metastatic squamous carcinoma: presentation in a single pelvic lymph node.

PubMed

Cobb, C J

1988-06-01

The presence of ectopic decidua in pelvic lymph nodes from patients with squamous carcinoma of the cervix makes evaluation for metastatic disease difficult due to the light microscopic similarity between decidua and sheets of squamous epithelial cells. A patient is present in whom decidualized endometriosis was intimately associated with metastatic moderately differentiate squamous carcinoma in a single pelvic lymph node. This phenomenon afforded an excellent opportunity to study the unique morphologic features that distinguish these two entities. A prior report of this kind was not found. In the absence of obvious squamous differentiation (i.e., intercellular bridges, dyskeratosis, and keratin "pearl" formation), as is frequently the case with squamous carcinoma of the cervix, the light microscopic features that are most useful in distinguishing squamous carcinoma from decidua include the presence of well-defined nests of cohesive cells, nuclear hyperchromasia, and cellular pleomorphism.

Gene conversion is strongly induced in human cells by double-strand breaks and is modulated by the expression of BCL-x(L)

NASA Technical Reports Server (NTRS)

Wiese, Claudia; Pierce, Andrew J.; Gauny, Stacey S.; Jasin, Maria; Kronenberg, Amy; Chatterjee, A. (Principal Investigator)

2002-01-01

Homology-directed repair (HDR) of DNA double-strand breaks (DSBs) contributes to the maintenance of genomic stability in rodent cells, and it has been assumed that HDR is of similar importance in DSB repair in human cells. However, some outcomes of homologous recombination can be deleterious, suggesting that factors exist to regulate HDR. We demonstrated previously that overexpression of BCL-2 or BCL-x(L) enhanced the frequency of X-ray-induced TK1 mutations, including loss of heterozygosity events presumed to arise by mitotic recombination. The present study was designed to test whether HDR is a prominent DSB repair pathway in human cells and to determine whether ectopic expression of BCL-x(L) affects HDR. Using TK6-neo cells, we find that a single DSB in an integrated HDR reporter stimulates gene conversion 40-50-fold, demonstrating efficient DSB repair by gene conversion in human cells. Significantly, DSB-induced gene conversion events are 3-4-fold more frequent in TK6 cells that stably overexpress the antiapoptotic protein BCL-X(L). Thus, HDR plays an important role in maintaining genomic integrity in human cells, and ectopic expression of BCL-x(L) enhances HDR of DSBs. This is the first study to highlight a function for BCL-x(L) in modulating DSB repair in human cells.

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

Wang, Luo-Qiao; Zhang, Yue; Yan, Huan

miR-373 was reported to be elevated in several tumors; however, the role of miR-373 in cervical cancer has not been investigated. In this study we aimed to investigate the role of miR-373 in tumorigenicity of cervical cancer cells in vivo and in vitro. The expression of miR-373 was investigated using real-time reverse transcription-polymerase chain reaction assay in 45 cervical specimens and cervical cancer cell lines. The role of miR-373 in tumorigenicity of cervical cancer cells was assessed by cell proliferation, colony formation in vitro as well as tumor growth assays in vivo with the overexpression of miR-373 or gene silencing. The functional target genemore » of miR-373 in cervical cancer cells was identified using integrated bioinformatics analysis, gene expression arrays, and luciferase assay. We founded that the expression of miR-373 is upregulated in human cervical cancer tissues and cervical carcinoma cell lines when compared to the corresponding noncancerous tissues. Ectopic overexpression of miR-373 in human cervical cancer cells promoted cell growth in vitro and tumorigenicity in vivo, whereas silencing the expression of miR-373 decreased the rate of cell growth. YOD1 was identified as a direct and functional target of miR-373 in cervical cancer cells. Expression levels of miR-373 were inversely correlated with YOD1 levels in human cervical cancer tissues. RNAi-mediated knockdown of YOD1 phenocopied the proliferation-promoting effect of miR-373. Moreover, overexpression of YOD1 abrogated miR-373-induced proliferation of cervical cancer cells. These results demonstrate that miR-373 increases proliferation by directly targeting YOD1, a new potential therapeutic target in cervical cancer. - Highlights: • The expression of miR-373 is upregulated in human cervical cancer tissues. • miR-373 effects as oncogenic miRNA in cervical cancer in vitro and in vivo. • miR-373 increases proliferation of cervical cancer cells by directly targeting YOD1.« less

SOX2 regulates self-renewal and tumorigenicity of stem-like cells of head and neck squamous cell carcinoma.

PubMed

Lee, S H; Oh, S-Y; Do, S I; Lee, H J; Kang, H J; Rho, Y S; Bae, W J; Lim, Y C

2014-11-25

Head and neck squamous cell carcinomas (HNSCCs) display cellular heterogeneity and contain cancer stem cells (CSCs). Sex-determining region Y [SRY]-box (SOX)2 is an important regulator of embryonic stem cell fate and is aberrantly expressed in several types of human tumours. Nonetheless, the role of SOX2 in HNSCC remains unclear. We created cells ectopically expressing SOX2 from previously established HNSCC cells and examined the cell proliferation, self-renewal capacity, and chemoresistance of these cells compared with control cells. In addition, we knocked down SOX2 in primary spheres obtained from HNSCC tumour tissue and assessed the attenuation of stemness-associated traits in these cells in vitro and in vivo. Furthermore, we examined the clinical relevance of SOX2 expression in HNSCC patients. SOX2 is aberrantly expressed in primary tissue of HNSCC patients but not in healthy tissue. SOX2 expression correlated with tumour recurrence and poor prognosis of HNSCC patients. Ectopic expression of SOX2 induced cell proliferation via cyclin B1 expression and stemness-associated features, such as self-renewal and chemoresistance. In addition, a knockdown of SOX2 in HNSCC CSCs attenuated their self-renewal capacity, chemoresistance (through ABCG2 suppression), invasion capacity (via snail downregulation), and in vivo tumorigenicity. These results suggest that SOX2 may have important roles in the 'stemness' and progression of HNSCC. Targeting SOX2-positive tumour cells (CSCs) could be a new therapeutic strategy in HNSCCs.

Disruption of biomineralization pathways in spinal tissues of a mouse model of diffuse idiopathic skeletal hyperostosis.

PubMed

Ii, Hisataka; Warraich, Sumeeta; Tenn, Neil; Quinonez, Diana; Holdsworth, David W; Hammond, James R; Dixon, S Jeffrey; Séguin, Cheryle A

2016-09-01

Equilibrative nucleoside transporter 1 (ENT1) mediates passage of adenosine across the plasma membrane. We reported previously that mice lacking ENT1 (ENT1(-/-)) exhibit progressive ectopic mineralization of spinal tissues resembling diffuse idiopathic skeletal hyperostosis (DISH) in humans. Here, we investigated mechanisms underlying aberrant mineralization in ENT1(-/-) mice. Micro-CT revealed ectopic mineralization of spinal tissues in both male and female ENT1(-/-) mice, involving the annulus fibrosus of the intervertebral discs (IVDs) of older mice. IVDs were isolated from wild-type and ENT1(-/-) mice at 2months of age (prior to disc mineralization), 4, and 6months of age (disc mineralization present) and processed for real-time PCR, cell isolation, or histology. Relative to the expression of ENTs in other tissues, ENT1 was the primary nucleoside transporter expressed in wild-type IVDs and mediated the functional uptake of [(3)H]2-chloroadenosine by annulus fibrosus cells. No differences in candidate gene expression were detected in IVDs from ENT1(-/-) and wild-type mice at 2 or 4months of age. However, at 6months of age, expression of genes that inhibit biomineralization Mgp, Enpp1, Ank, and Spp1 were reduced in IVDs from ENT1(-/-) mice. To assess whether changes detected in ENT1(-/-) mice were cell autonomous, annulus fibrosus cell cultures were established. Compared to wild-type cells, cells isolated from ENT1(-/-) IVDs at 2 or 6months of age demonstrated greater activity of alkaline phosphatase, a promoter of biomineralization. Cells from 2-month-old ENT1(-/-) mice also showed greater mineralization than wild-type. Interestingly, altered localization of alkaline phosphatase activity was detected in the inner annulus fibrosus of ENT1(-/-) mice in vivo. Alkaline phosphatase activity, together with the marked reduction in mineralization inhibitors, is consistent with the mineralization of IVDs seen in ENT1(-/-) mice at older ages. These findings establish that both cell-autonomous and systemic mechanisms contribute to ectopic mineralization in ENT1(-/-) mice. Copyright © 2016 Elsevier Inc. All rights reserved.

Genome-Edited, TH-expressing Neuroblastoma Cells as a Disease Model for Dopamine-Related Disorders: A Proof-of-Concept Study on DJ-1-deficient Parkinsonism

PubMed Central

Prasuhn, Jannik; Mårtensson, Christoph U.; Krajka, Victor; Klein, Christine; Rakovic, Aleksandar

2018-01-01

Impairment of the dopaminergic (DA) system is a common cause of several movement disorders including Parkinson’s disease (PD), however, little is known about the underlying disease mechanisms. The recent development of stem-cell-based protocols for the generation of DA neurons partially solved this issue, however, this technology is costly and time-consuming. Commonly used cell lines, i.e., neuroblastoma (SHSY5Y) and PC12 cells are still widely used to investigate PD and significantly contributed to our understanding of mechanisms involved in development of the disease. However, they either do not express DA at all or require additional, only partially efficient differentiations in order to produce DA. Here we generated and characterized transgenic SH-SY5Y cells, ectopically expressing tyrosine hydroxylase (SHTH+), that can be used as a homogenous, DA-producing model to study alterations in DA metabolism and oxidative stress. We demonstrated that SHTH+ produce high levels of DA, 3,4-dihydroxyphenylacetic acid (DOPAC), and homovanillic acid (HVA) making this model suitable to investigate not only alterations in DA synthesis but also its turnover. We also provide evidence for the presence of other enzymes involved in DA synthesis and its turnover in these cells. Finally, we showed that these cells can easily be genetically modified using CRISPR/Cas9 technology in order to study genetically defined forms of movement disorders using DJ1-linked PD as a model. PMID:29379417

Zebrafish enpp1 mutants exhibit pathological mineralization, mimicking features of generalized arterial calcification of infancy (GACI) and pseudoxanthoma elasticum (PXE).

PubMed

Apschner, Alexander; Huitema, Leonie F A; Ponsioen, Bas; Peterson-Maduro, Josi; Schulte-Merker, Stefan

2014-07-01

In recent years it has become clear that, mechanistically, biomineralization is a process that has to be actively inhibited as a default state. This inhibition must be released in a rigidly controlled manner in order for mineralization to occur in skeletal elements and teeth. A central aspect of this concept is the tightly controlled balance between phosphate, a constituent of the biomineral hydroxyapatite, and pyrophosphate, a physiochemical inhibitor of mineralization. Here, we provide a detailed analysis of a zebrafish mutant, dragonfish (dgf), which is mutant for ectonucleoside pyrophosphatase/phosphodiesterase 1 (Enpp1), a protein that is crucial for supplying extracellular pyrophosphate. Generalized arterial calcification of infancy (GACI) is a fatal human disease, and the majority of cases are thought to be caused by mutations in ENPP1. Furthermore, some cases of pseudoxanthoma elasticum (PXE) have recently been linked to ENPP1. Similar to humans, we show here that zebrafish enpp1 mutants can develop ectopic calcifications in a variety of soft tissues - most notably in the skin, cartilage elements, the heart, intracranial space and the notochord sheet. Using transgenic reporter lines, we demonstrate that ectopic mineralizations in these tissues occur independently of the expression of typical osteoblast or cartilage markers. Intriguingly, we detect cells expressing the osteoclast markers Trap and CathepsinK at sites of ectopic calcification at time points when osteoclasts are not yet present in wild-type siblings. Treatment with the bisphosphonate etidronate rescues aspects of the dgf phenotype, and we detected deregulated expression of genes that are involved in phosphate homeostasis and mineralization, such as fgf23, npt2a, entpd5 and spp1 (also known as osteopontin). Employing a UAS-GalFF approach, we show that forced expression of enpp1 in blood vessels or the floorplate of mutant embryos is sufficient to rescue the notochord mineralization phenotype. This indicates that enpp1 can exert its function in tissues that are remote from its site of expression. © 2014. Published by The Company of Biologists Ltd.

Characterization of Reversibly Immortalized Calvarial Mesenchymal Progenitor Cells.

PubMed

Shenaq, Deana S; Teven, Chad M; Seitz, Iris A; Rastegar, Farbod; Greives, Matthew R; He, Tong-Chuan; Reid, Russell R

2015-06-01

Bone morphogenetic proteins (BMPs) play a sentinel role in osteoblastic differentiation, and their implementation into clinical practice can revolutionize cranial reconstruction. Preliminary data suggest a therapeutic role of adenoviral gene delivery of BMPs in murine calvarial defect healing. Poor transgene expression inherent in direct adenoviral therapy prompted investigation of cell-based strategies. To isolate and immortalize calvarial cells as a potential progenitor source for osseous tissue engineering. Cells were isolated from murine skulls, cultured, and transduced with a retroviral vector bearing the loxP-flanked SV40 large T antigen. Immortalized calvarial cells (iCALs) were evaluated via light microscopy, immunohistochemistry, and flow cytometry to determine whether the immortalization process altered cell morphology or progenitor cell profile. Immortalized calvarial cells were then infected with adenoviral vectors encoding BMP-2 or GFP and assessed for early and late stages of osteogenic differentiation. Immortalization of calvarial cells did not alter cell morphology as demonstrated by phase contrast microscopy. Mesenchymal progenitor cell markers CD166, CD73, CD44, and CD105 were detected at varying levels in both primary cells and iCALs. Significant elevations in alkaline phosphatase activity, osteocalcin mRNA transcription, and matrix mineralization were detected in BMP-2 treated iCALs compared with GFP-treated cells. Gross and histological analyses revealed ectopic bone production from treated cells compared with controls in an in vivo stem cell implantation assay. We have established an immortalized osteoprogenitor cell line from juvenile calvarial cells that retain a progenitor cell phenotype and can successfully undergo osteogenic differentiation upon BMP-2 stimulation. These cells provide a valuable platform to investigate the molecular mechanisms underlying intramembranous bone formation and to screen for factors/small molecules that can facilitate the healing of osseous defects in the craniofacial skeleton.

Involvement of calprotectin (S100A8/A9) in molecular pathways associated with HNSCC

PubMed Central

Khammanivong, Ali; Sorenson, Brent S.; Ross, Karen F.; Dickerson, Erin B.; Hasina, Rifat; Lingen, Mark W.; Herzberg, Mark C.

2016-01-01

Calprotectin (S100A8/A9), a heterodimeric protein complex of calcium-binding proteins S100A8 and S100A9, plays key roles in cell cycle regulation and inflammation, with potential functions in squamous cell differentiation. While upregulated in many cancers, S100A8/A9 is downregulated in squamous cell carcinomas of the cervix, esophagus, and the head and neck (HNSCC). We previously reported that ectopic S100A8/A9 expression inhibits cell cycle progression in carcinoma cells. Here, we show that declining expression of S100A8/A9 in patients with HNSCC is associated with increased DNA methylation, less differentiated tumors, and reduced overall survival. Upon ectopic over-expression of S100A8/A9, the cancer phenotype of S100A8/A9-negative carcinoma cells was suppressed in vitro and tumor growth in vivo was significantly decreased. MMP1, INHBA, FST, LAMC2, CCL3, SULF1, and SLC16A1 were significantly upregulated in HNSCC but were downregulated by S100A8/A9 expression. Our findings strongly suggest that downregulation of S100A8/A9 through epigenetic mechanisms may contribute to increased proliferation, malignant transformation, and disease progression in HNSCC. PMID:26883112

Involvement of calprotectin (S100A8/A9) in molecular pathways associated with HNSCC.

PubMed

Khammanivong, Ali; Sorenson, Brent S; Ross, Karen F; Dickerson, Erin B; Hasina, Rifat; Lingen, Mark W; Herzberg, Mark C

2016-03-22

Calprotectin (S100A8/A9), a heterodimeric protein complex of calcium-binding proteins S100A8 and S100A9, plays key roles in cell cycle regulation and inflammation, with potential functions in squamous cell differentiation. While upregulated in many cancers, S100A8/A9 is downregulated in squamous cell carcinomas of the cervix, esophagus, and the head and neck (HNSCC). We previously reported that ectopic S100A8/A9 expression inhibits cell cycle progression in carcinoma cells. Here, we show that declining expression of S100A8/A9 in patients with HNSCC is associated with increased DNA methylation, less differentiated tumors, and reduced overall survival. Upon ectopic over-expression of S100A8/A9, the cancer phenotype of S100A8/A9-negative carcinoma cells was suppressed in vitro and tumor growth in vivo was significantly decreased. MMP1, INHBA, FST, LAMC2, CCL3, SULF1, and SLC16A1 were significantly upregulated in HNSCC but were downregulated by S100A8/A9 expression. Our findings strongly suggest that downregulation of S100A8/A9 through epigenetic mechanisms may contribute to increased proliferation, malignant transformation, and disease progression in HNSCC.

Periodontal ligament versus bone marrow mesenchymal stem cells in combination with Bio-Oss scaffolds for ectopic and in situ bone formation: A comparative study in the rat.

PubMed

Yu, Bo-Han; Zhou, Qian; Wang, Zuo-Lin

2014-08-01

The aim of this study was to compare the osteogenic effects of periodontal ligament stem cells (PDLSCs) versus bone marrow mesenchymal stem cells (BMMSCs) in combination with Bio-Oss scaffolds on subcutaneous and critical-size defects in the immunodeficient rat calvarium. PDLSCs and BMMSCs were obtained from the same canine donor. Twenty-four rats were randomly assigned to one of four experimental groups (n = 6 each): group A (no-graft negative control), group B (Bio-Oss positive control), group C (BMMSC/Bio-Oss test group), and group D (PDLSC/Bio-Oss test group). Eight weeks post-transplantation, ectopic and in situ bone regeneration was evaluated by micro-computed tomography (µ-CT), histology, histomorphometry, and immunohistochemistry. The stem cell/Bio-Oss constructs were significantly superior to the controls in terms of their ability to promote osteogenesis (p < 0.01), while the PDLSC/Bio-Oss construct tended to be superior to the BMMSC/Bio-Oss construct. Thus, engineered stem cell/Bio-Oss complexes can successfully reconstruct critical-size defects in rats, and PDLSCs and BMMSCs are both suitable as seed cells. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

A novel model for ectopic, chronic, intravital multiphoton imaging of bone marrow vasculature and architecture in split femurs

PubMed Central

Bălan, Mirela; Kiefer, Friedemann

2015-01-01

Creating a model for intravital visualization of femoral bone marrow, a major site of hematopoiesis in adult mammalian organisms, poses a serious challenge, in that it needs to overcome bone opacity and the inaccessibility of marrow. Furthermore, meaningful analysis of bone marrow developmental and differentiation processes requires the repetitive observation of the same site over long periods of time, which we refer to as chronic imaging. To surmount these issues, we developed a chronic intravital imaging model that allows the observation of split femurs, ectopically transplanted into a dorsal skinfold chamber of a host mouse. Repeated, long term observations are facilitated by multiphoton microscopy, an imaging technique that combines superior imaging capacity at greater tissue depth with low phototoxicity. The transplanted, ectopic femur was stabilized by its sterile environment and rapidly connected to the host vasculature, allowing further development and observation of extended processes. After optimizing transplant age and grafting procedure, we observed the development of new woven bone and maturation of secondary ossification centers in the transplanted femurs, preceded by the sprouting of a sinusoidal-like vascular network, which was almost entirely composed of femoral endothelial cells. After two weeks, the transplant was still populated with stromal and haematopoietic cells belonging both to donor and host. Over this time frame, the transplant partially retained myeloid progenitor cells with single and multi-lineage differentiation capacity. In summary, our model allowed repeated intravital imaging of bone marrow angiogenesis and hematopoiesis. It represents a promising starting point for the development of improved chronic optical imaging models for femoral bone marrow. PMID:28243515

Dexamethasone treatment induces the reprogramming of pancreatic acinar cells to hepatocytes and ductal cells.

PubMed

Al-Adsani, Amani; Burke, Zoë D; Eberhard, Daniel; Lawrence, Katherine L; Shen, Chia-Ning; Rustgi, Anil K; Sakaue, Hiroshi; Farrant, J Mark; Tosh, David

2010-10-27

The pancreatic exocrine cell line AR42J-B13 can be reprogrammed to hepatocytes following treatment with dexamethasone. The question arises whether dexamethasone also has the capacity to induce ductal cells as well as hepatocytes. AR42J-B13 cells were treated with and without dexamethasone and analyzed for the expression of pancreatic exocrine, hepatocyte and ductal markers. Addition of dexamethasone inhibited pancreatic amylase expression, induced expression of the hepatocyte marker transferrin as well as markers typical of ductal cells: cytokeratin 7 and 19 and the lectin peanut agglutinin. However, the number of ductal cells was low compared to hepatocytes. The proportion of ductal cells was enhanced by culture with dexamethasone and epidermal growth factor (EGF). We established several features of the mechanism underlying the transdifferentiation of pancreatic exocrine cells to ductal cells. Using a CK19 promoter reporter, we show that a proportion of the ductal cells arise from differentiated pancreatic exocrine-like cells. We also examined whether C/EBPβ (a transcription factor important in the conversion of pancreatic cells to hepatocytes) could alter the conversion from acinar cells to a ductal phenotype. Overexpression of an activated form of C/EBPβ in dexamethasone/EGF-treated cells provoked the expression of hepatocyte markers and inhibited the expression of ductal markers. Conversely, ectopic expression of a dominant-negative form of C/EBPβ, liver inhibitory protein, inhibited hepatocyte formation in dexamethasone-treated cultures and enhanced the ductal phenotype. These results indicate that hepatocytes and ductal cells may be induced from pancreatic exocrine AR42J-B13 cells following treatment with dexamethasone. The conversion from pancreatic to hepatocyte or ductal cells is dependent upon the expression of C/EBPβ.

Transcriptional upregulation of p19INK4d upon diverse genotoxic stress is critical for optimal DNA damage response.

PubMed

Ceruti, Julieta M; Scassa, María E; Marazita, Mariela C; Carcagno, Abel C; Sirkin, Pablo F; Cánepa, Eduardo T

2009-06-01

p19INK4d promotes survival of several cell lines after UV irradiation due to enhanced DNA repair, independently of CDK4 inhibition. To further understand the action of p19INK4d in the cellular response to DNA damage, we aimed to elucidate whether this novel regulator plays a role only in mechanisms triggered by UV or participates in diverse mechanisms initiated by different genotoxics. We found that p19INK4d is induced in cells injured with cisplatin or beta-amyloid peptide as robustly as with UV. The mentioned genotoxics transcriptionally activate p19INK4d expression as demonstrated by run-on assay without influencing its mRNA stability and with partial requirement of protein synthesis. It is not currently known whether DNA damage-inducible genes are turned on by the DNA damage itself or by the consequences of that damage. Experiments carried out in cells transfected with distinct damaged DNA structures revealed that the damage itself is not responsible for the observed up-regulation. It is also not known whether the increased expression of DNA-damage-inducible genes is related to immediate protective responses such as DNA repair or to more delayed responses such as cell cycle arrest or apoptosis. We found that ectopic expression of p19INK4d improves DNA repair ability and protects neuroblastoma cells from apoptosis caused by cisplatin or beta-amyloid peptide. Using clonal cell lines where p19INK4d levels can be modified at will, we show that p19INK4d expression correlates with increased survival and clonogenicity. The results presented here, prompted us to suggest that p19INK4d displays an important role in an early stage of cellular DNA damage response.

TRIP-Br2 promotes oncogenesis in nude mice and is frequently overexpressed in multiple human tumors

PubMed Central

Cheong, Jit Kong; Gunaratnam, Lakshman; Zang, Zhi Jiang; Yang, Christopher M; Sun, Xiaoming; Nasr, Susan L; Sim, Khe Guan; Peh, Bee Keow; Rashid, Suhaimi Bin Abdul; Bonventre, Joseph V; Salto-Tellez, Manuel; Hsu, Stephen I

2009-01-01

Background Members of the TRIP-Br/SERTAD family of mammalian transcriptional coregulators have recently been implicated in E2F-mediated cell cycle progression and tumorigenesis. We, herein, focus on the detailed functional characterization of the least understood member of the TRIP-Br/SERTAD protein family, TRIP-Br2 (SERTAD2). Methods Oncogenic potential of TRIP-Br2 was demonstrated by (1) inoculation of NIH3T3 fibroblasts, which were engineered to stably overexpress ectopic TRIP-Br2, into athymic nude mice for tumor induction and (2) comprehensive immunohistochemical high-throughput screening of TRIP-Br2 protein expression in multiple human tumor cell lines and human tumor tissue microarrays (TMAs). Clinicopathologic analysis was conducted to assess the potential of TRIP-Br2 as a novel prognostic marker of human cancer. RNA interference of TRIP-Br2 expression in HCT-116 colorectal carcinoma cells was performed to determine the potential of TRIP-Br2 as a novel chemotherapeutic drug target. Results Overexpression of TRIP-Br2 is sufficient to transform murine fibroblasts and promotes tumorigenesis in nude mice. The transformed phenotype is characterized by deregulation of the E2F/DP-transcriptional pathway through upregulation of the key E2F-responsive genes CYCLIN E, CYCLIN A2, CDC6 and DHFR. TRIP-Br2 is frequently overexpressed in both cancer cell lines and multiple human tumors. Clinicopathologic correlation indicates that overexpression of TRIP-Br2 in hepatocellular carcinoma is associated with a worse clinical outcome by Kaplan-Meier survival analysis. Small interfering RNA-mediated (siRNA) knockdown of TRIP-Br2 was sufficient to inhibit cell-autonomous growth of HCT-116 cells in vitro. Conclusion This study identifies TRIP-Br2 as a bona-fide protooncogene and supports the potential for TRIP-Br2 as a novel prognostic marker and a chemotherapeutic drug target in human cancer. PMID:19152710

The R2R3MYB VvMYBPA1 from grape reprograms the phenylpropanoid pathway in tobacco flowers.

PubMed

Passeri, Valentina; Martens, Stefan; Carvalho, Elisabete; Bianchet, Chantal; Damiani, Francesco; Paolocci, Francesco

2017-08-01

This work shows that, in tobacco, the ectopic expression of VvMYBPA1 , a grape regulator of proanthocyanidin biosynthesis, up- or down-regulates different branches of the phenylproanoid pathway, in a structure-specific fashion. Proanthocyanidins are flavonoids of paramount importance for animal and human diet. Research interest increasingly tilts towards generating crops enriched with these health-promoting compounds. Flavonoids synthesis is regulated by the MBW transcriptional complex, made of R2R3MYB, bHLH and WD40 proteins, with the MYB components liable for channeling the complex towards specific branches of the pathway. Hence, using tobacco as a model, here, we tested if the ectopic expression of the proanthocyanidin regulator VvMYBPA1 from grape induces the biosynthesis of these compounds in not-naturally committed cells. Here, we show, via targeted transcriptomic and metabolic analyses of primary transgenic lines and their progeny, that VvMYBPA1 alters the phenylpropanoid pathway in tobacco floral organs, in a structure-specific fashion. We also report that a modest VvMYBPA1 expression is sufficient to induce the expression of both proanthocyanidin-specific and early genes of the phenylpropanoid pathway. Consequently, proanthocyanidins and chlorogenic acids are induced or de novo synthetised in floral limbs, tubes and stamens. Other phenylpropanoid branches are conversely induced or depleted according to the floral structure. Our study documents a novel and distinct function of VvMYBPA1 with respect to other MYBs regulating proanthocyanidins. Present findings may have major implications in designing strategies for enriching crops with health-promoting compounds.

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

PubMed

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

2009-12-15

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

Ectopic expression of Triticum aestivum SERK genes (TaSERKs) control plant growth and development in Arabidopsis.

PubMed

Singh, Akanksha; Khurana, Paramjit

2017-09-28

Somatic embryogenesis receptor kinases (SERKs) belong to a small gene family of receptor-like kinases involved in signal transduction. A total of 54 genes were shortlisted from the wheat genome survey sequence of which 5 were classified as SERKs and 49 were identified as SERK-like (SERLs). Tissue- specific expression of TaSERKs at major developmental stages of wheat corroborates their indispensable role during somatic and zygotic embryogenesis. TaSERK transcripts show inherent differences in their hormonal sensitivities, i.e. TaSERK2 and TaSERK3 elicits auxin- specific responses while TaSERK1, 4 and 5 were more specific towards BR-mediated regulation. The ectopic expression of TaSERK1, 2, 3, 4 and 5 in Arabidopsis led to enhanced plant height, larger silique size and increased seed yield. Zygotic embryogenesis specific genes showed a differential pattern in TaSERK Arabidopsis transgenics specifically in the silique tissues. Elongated hypocotyls and enhanced root growth were observed in the overexpression transgenic lines of all five TaSERKs. The inhibitory action of auxin and brassinosteroid in all the TaSERK transgenic lines indicates their role in regulating root development. The results obtained imply redundant functions of TaSERKs in maintaining plant growth and development.

Ectopic overexpression of LAPTM5 results in lysosomal targeting and induces Mcl-1 down-regulation, Bak activation, and mitochondria-dependent apoptosis in human HeLa cells

PubMed Central

Jun, Do Youn; Kim, Hyejin; Jang, Won Young; Lee, Ji Young; Fukui, Kiyoshi; Kim, Young Ho

2017-01-01

Human lysosomal-associated protein multispanning membrane 5 (LAPTM5) was identified by an ordered differential display-polymerase chain reaction (ODD-PCR) as an up-regulated cDNA fragment during 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced differentiation of U937 cells into monocytes/macrophages. After TPA-treatment, the levels of LAPTM5 mRNA and protein increased and reached a maximum at 18–36 h. In healthy human tissues, LAPTM5 mRNA was expressed at high levels in hematopoietic cells and tissues, at low levels in the lung and fetal liver, and was not detected in other non-hematopoietic tissues. LAPTM5 mRNA was detected in immature malignant cells of myeloid lineage, such as K562, HL-60, U937, and THP-1 cells, and in unstimulated peripheral T cells, but was absent or barely detectable in lymphoid malignant or non-hematopoietic malignant cells. The LAPTM5 level in HL-60 cells increased more significantly during TPA-induced monocyte/macrophage differentiation than during DMSO-induced granulocyte differentiation. Ectopic expression of GFP-LAPTM5 or LAPTM5 in HeLa cells exhibited the localization of LAPTM5 to the lysosome. In HeLa cells overexpressing LAPTM5, the Mcl-1 and Bid levels declined markedly and apoptosis was induced via Bak activation, Δψm loss, activation of caspase-9, -8 and -3, and PARP degradation without accompanying necrosis. However, these LAPTM5-induced apoptotic events except for the decline of Bid level were completely abrogated by concomitant overexpression of Mcl-1. The pan-caspase inhibitor (z-VAD-fmk) could suppress the LAPTM5-induced apoptotic sub-G1 peak by ~40% but failed to block the induced Δψm loss, whereas the broad-range inhibitor of cathepsins (Cathepsin Inhibitor I) could suppress the LAPTM5-induced apoptotic sub-G1 peak and Δψm loss, by ~22% and ~23%, respectively, suggesting that the LAPTM5-mediated Δψm loss was exerted at least in part in a cathepsin-dependent manner. Together, these results demonstrate that ectopic overexpression of LAPTM5 in HeLa cells induced apoptosis via cleavage of Mcl-1 and Bid by a LAPTM5-associated lysosomal pathway, and subsequent activation of the mitochondria-dependent caspase cascade. PMID:28464033

Rh Incompatibility

MedlinePlus

... An ectopic pregnancy, a miscarriage, or an induced abortion. (An ectopic pregnancy is a pregnancy that starts ... An ectopic pregnancy, a miscarriage, or an induced abortion. (An ectopic pregnancy is a pregnancy that starts ...

Expression and Functional Pathway Analysis of Nuclear Receptor NR2F2 in Ovarian Cancer

PubMed Central

Hawkins, Shannon M.; Loomans, Holli A.; Wan, Ying-Wooi; Ghosh-Choudhury, Triparna; Coffey, Donna; Xiao, Weimin; Liu, Zhandong; Sangi-Haghpeykar, Haleh

2013-01-01

Context: Recent evidence implicates the orphan nuclear receptor, nuclear receptor subfamily 2, group F, member 2 (NR2F2; chicken ovalbumin upstream promoter-transcription factor II) as both a master regulator of angiogenesis and an oncogene in prostate and other human cancers. Objective: The objective of the study was to determine whether NR2F2 plays a role in ovarian cancer and dissect its potential mechanisms of action. Design, Setting, and Patients: We examined NR2F2 expression in healthy ovary and ovarian cancers using quantitative PCR and immunohistochemistry. NR2F2 expression was targeted in established ovarian cancer cell lines to assess the impact of dysregulated NR2F2 expression in the epithelial compartment of ovarian cancers. Results: Our results indicate that NR2F2 is robustly expressed in the stroma of healthy ovary with little or no expression in epithelia lining the ovarian surface, clefts, or crypts. This pattern of NR2F2 expression was markedly disrupted in ovarian cancers, in which decreased levels of stromal expression and ectopic epithelial expression were frequently observed. Ovarian cancers with the most disrupted patterns of NR2F2 were associated with significantly shorter disease-free interval by Kaplan-Meier analysis. Targeting NR2F2 expression in established ovarian cancer cell lines enhanced apoptosis and increased proliferation. In addition, we found that NR2F2 regulates the expression of NEK2, RAI14, and multiple other genes involved in the cell cycle, suggesting potential pathways by which dysregulated expression of NR2F2 impacts ovarian cancer. Conclusions: These results uncover novel roles for NR2F2 in ovarian cancer and point to a unique scenario in which a single nuclear receptor plays potentially distinct roles in the stromal and epithelial compartments of the same tissue. PMID:23690307