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Sample records for aberrant cell growth

  1. Growth rate of late passage sarcoma cells is independent of epigenetic events but dependent on the amount of chromosomal aberrations

    SciTech Connect

    Becerikli, Mustafa; Jacobsen, Frank; Rittig, Andrea; Köhne, Wiebke; Nambiar, Sandeep; Mirmohammadsadegh, Alireza; Stricker, Ingo; Tannapfel, Andrea; Wieczorek, Stefan; Epplen, Joerg Thomas; Tilkorn, Daniel; Steinstraesser, Lars

    2013-07-15

    Soft tissue sarcomas (STS) are characterized by co-participation of several epigenetic and genetic events during tumorigenesis. Having bypassed cellular senescence barriers during oncogenic transformation, the factors further affecting growth rate of STS cells remain poorly understood. Therefore, we investigated the role of gene silencing (DNA promoter methylation of LINE-1, PTEN), genetic aberrations (karyotype, KRAS and BRAF mutations) as well as their contribution to the proliferation rate and migratory potential that underlies “initial” and “final” passage sarcoma cells. Three different cell lines were used, SW982 (synovial sarcoma), U2197 (malignant fibrous histiocytoma (MFH)) and HT1080 (fibrosarcoma). Increased proliferative potential of final passage STS cells was not associated with significant differences in methylation (LINE-1, PTEN) and mutation status (KRAS, BRAF), but it was dependent on the amount of chromosomal aberrations. Collectively, our data demonstrate that these fairly differentiated/advanced cancer cell lines have still the potential to gain an additional spontaneous growth benefit without external influences and that maintenance of increased proliferative potential towards longevity of STS cells (having crossed senescence barriers) may be independent of overt epigenetic alterations. -- Highlights: Increased proliferative potential of late passage STS cells was: • Not associated with epigenetic changes (methylation changes at LINE-1, PTEN). • Not associated with mutation status of KRAS, BRAF. • Dependent on presence/absence of chromosomal aberrations.

  2. Werner's syndrome: a review of recent research with an analysis of connective tissue metabolism, growth control of cultured cells, and chromosomal aberrations.

    PubMed

    Salk, D

    1982-01-01

    Werner's syndrome is a rare, autosomal recessive condition with multiple progeroid features, but it is an imitation of aging rather than accelerated or premature senescence. Somatic chromosome aberrations occur in multiple tissues in vivo and in vitro, and there is an increased incidence of neoplasia. Thus. Werner's syndrome can be classified in the group of chromosome instability syndromes. Recent findings provide additional support for the concept that there is an aberration of connective tissue metabolism in Werner's syndrome, but it is unclear whether this is a primary or secondary manifestation of the underlying genetic defect. Abnormal growth characteristics are observed in cultured skin fibroblast-like cells and this provides another avenue for current research. Identification of the basic genetic defect in Werner's syndrome might clarify our understanding of the normal aging process in general, or might elucidate specific aspects such as the development of neoplasia, atherosclerosis, diabetes, or osteoporosis.

  3. WISP genes are members of the connective tissue growth factor family that are up-regulated in wnt-1-transformed cells and aberrantly expressed in human colon tumors.

    PubMed

    Pennica, D; Swanson, T A; Welsh, J W; Roy, M A; Lawrence, D A; Lee, J; Brush, J; Taneyhill, L A; Deuel, B; Lew, M; Watanabe, C; Cohen, R L; Melhem, M F; Finley, G G; Quirke, P; Goddard, A D; Hillan, K J; Gurney, A L; Botstein, D; Levine, A J

    1998-12-01

    Wnt family members are critical to many developmental processes, and components of the Wnt signaling pathway have been linked to tumorigenesis in familial and sporadic colon carcinomas. Here we report the identification of two genes, WISP-1 and WISP-2, that are up-regulated in the mouse mammary epithelial cell line C57MG transformed by Wnt-1, but not by Wnt-4. Together with a third related gene, WISP-3, these proteins define a subfamily of the connective tissue growth factor family. Two distinct systems demonstrated WISP induction to be associated with the expression of Wnt-1. These included (i) C57MG cells infected with a Wnt-1 retroviral vector or expressing Wnt-1 under the control of a tetracyline repressible promoter, and (ii) Wnt-1 transgenic mice. The WISP-1 gene was localized to human chromosome 8q24.1-8q24.3. WISP-1 genomic DNA was amplified in colon cancer cell lines and in human colon tumors and its RNA overexpressed (2- to >30-fold) in 84% of the tumors examined compared with patient-matched normal mucosa. WISP-3 mapped to chromosome 6q22-6q23 and also was overexpressed (4- to >40-fold) in 63% of the colon tumors analyzed. In contrast, WISP-2 mapped to human chromosome 20q12-20q13 and its DNA was amplified, but RNA expression was reduced (2- to >30-fold) in 79% of the tumors. These results suggest that the WISP genes may be downstream of Wnt-1 signaling and that aberrant levels of WISP expression in colon cancer may play a role in colon tumorigenesis.

  4. Nanowire growth kinetics in aberration corrected environmental transmission electron microscopy

    DOE PAGES

    Chou, Yi -Chia; Panciera, Federico; Reuter, Mark C.; Stach, Eric A.; Ross, Frances M.

    2016-03-15

    Here, we visualize atomic level dynamics during Si nanowire growth using aberration corrected environmental transmission electron microscopy, and compare with lower pressure results from ultra-high vacuum microscopy. We discuss the importance of higher pressure observations for understanding growth mechanisms and describe protocols to minimize effects of the higher pressure background gas.

  5. 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

    SciTech Connect

    Ahluwalia, Amrita; Jones, Michael K.; Szabo, Sandor; Tarnawski, Andrzej S.

    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 and 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

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

    NASA Technical Reports Server (NTRS)

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

    1997-01-01

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

  7. Chromosome aberrations in ataxia telangiectasia cells exposed to heavy ions

    NASA Astrophysics Data System (ADS)

    Kawata, T.; Cucinotta, F.; George, K.; Wu, H.; Shigematsu, N.; Furusawa, Y.; Uno, T.; Isobe, K.; Ito, H.

    Understanding of biological effects of heavy ions is important to assess healt h risk in space. One of the most important issues may be to take into account individual susceptibility. Ataxia telangiectasia (A-T) cells are known to exhibit abnormal responses to radiations but the mechanism of hyper radiosensitivity of A-T still remains unknown. We report chromosome aberrations in normal human fibroblasts and AT fibroblasts exposed to low- and high-LET radiations. A chemical-induced premature chromosome condensation (PCC) technique combined with chromosome- painting technique was applied to score chromosome aberrations in G2/M-phase cells. Following gamma irradiation, GM02052 cells were approximately 5 times more sensitive to g-rays than AG1522 cells. GM02052 cells had a much higher frequency of deletions and misrejoining than AG1522 cells. When the frequency of complex type aberrations was compared, GM02052 cells showed more than 10 times higher frequency than AG1522 cells. The results will be compared with those obtained from high-LET irradiations.

  8. Optical aberrations, retinal image quality and eye growth: Experimentation and modeling

    NASA Astrophysics Data System (ADS)

    Tian, Yibin

    2007-12-01

    Retinal image quality is important for normal eye growth. Optical aberrations are of interest for two reasons: first, they degrade retinal images; second, they might provide some cues to defocus. Higher than normal ocular aberrations have been previously associated with human myopia. However, these studies were cross-sectional in design, and only reported aberrations in terms of root mean square (RMS) errors of Zernike coefficients, a poor metric of optical quality. This dissertation presents results from investigations of ocular optical aberrations, retinal image quality and eye growth in chicks and humans. A number of techniques were utilized, including Shack-Hartmann aberrometry, high-frequency A-scan ultrasonography, ciliary nerve section (CNX), photorefractive keratectomy (PRK) as well as computer simulations and modeling. A technique to extract light scatter information from Shack-Hartmann images was also developed. The main findings of the dissertation are summarized below. In young chicks, most ocular aberrations decreased with growth in both normal and CNX eyes, and there were diurnal fluctuations in some aberrations. Modeling suggested active reduction in higher order aberrations (HOAs) during early development. Although CNX eyes manifested greater than normal HOAs, they showed near normal growth. Retinal image degradation varied greatly among individual eyes post-PRK in young chicks. Including light scatter information into analyses of retinal image quality better estimated the latter. Albino eyes showed more severe retinal image degradation than normal eyes, due to increased optical aberrations and light scatter, but their growth was similar to those of normal eyes, implying that they are relatively insensitive to retina image quality. Although the above results questioned the influence of optical aberrations on early ocular growth, some optical quality metrics, derived from optical aberrations data, could predict how much the eyes of young chicks

  9. Cytogenetically aberrant cells in the stem cell compartment (CD34+lin-) in acute myeloid leukemia.

    PubMed

    Mehrotra, B; George, T I; Kavanau, K; Avet-Loiseau, H; Moore, D; Willman, C L; Slovak, M L; Atwater, S; Head, D R; Pallavicini, M G

    1995-08-01

    Leukemia may be viewed as a clonal expansion of blast cells; however, the role of primitive cells and/or stem cells in disease etiology and progression is unclear. We investigated stem cell involvement in leukemia using fluorescence in situ hybridization (FISH), immunofluorescence labeling of hematopoietic subpopulations, and flow cytometric analysis/sorting to discriminate and quantify cytogenetically aberrant stem cells in 12 acute myeloid leukemia (AML) and three myelodysplastic (MDS) specimens. Flow cytometric analysis and sorting were used to discriminate and collect a primitive subpopulation enriched in stem cells expressing CD34+ and lacking CD33 and CD38 (CD34+lin-). A subpopulation containing progenitors and differentiating myeloid cells expressed CD34, CD33, and CD38 (CD34+lin+). Nine specimens contained less than 10% CD34+ cells and, thus, were considered to be CD34- leukemias. Mature lymphoid, myeloid, and erythroid subpopulations were sorted on the basis of antigen-linked immunofluorescence. Cytogenetically aberrant cells in sorted subpopulations were identified using FISH with enumerator probes selected on the basis of diagnosis karyotype. Cytogenetically aberrant CD34+lin- cells were present at frequencies between 9% and 99% in all specimens. CD34+lin- cytogenetically aberrant cells comprised between 0.05% and 11.9% of the marrow/blood specimens. Cytogenetically aberrant CD34+lin+ cells constituted 0.01% tp 56% of the marrow/blood population. These data demonstrate that aberrant cells are present in primitive CD34+ stem cell compartments, even in CD34- leukemias. Stem cell involvement was confirmed further by sorting lymphoid and erythroid subpopulations from eight specimens in which the predominant leukemic population lacked lymphoid/erythroid differentiation markers. In these specimens, as well as in multiple lineages, suggests involvement of a cell(s) with multilineage capabilities. The ability of aberrant CD34+lin- stem cells to contribute to

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

    NASA Technical Reports Server (NTRS)

    Thaller, Lawrence H.; Quinzio, Michael V.

    1997-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    1995-01-01

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

  12. Chromosome therapy. Correction of large chromosomal aberrations by inducing ring chromosomes in induced pluripotent stem cells (iPSCs).

    PubMed

    Kim, Taehyun; Bershteyn, Marina; Wynshaw-Boris, Anthony

    2014-01-01

    The fusion of the short (p) and long (q) arms of a chromosome is referred to as a "ring chromosome." Ring chromosome disorders occur in approximately 1 in 50,000-100,000 patients. Ring chromosomes can result in birth defects, mental disabilities, and growth retardation if additional genes are deleted during the formation of the ring. Due to the severity of these large-scale aberrations affecting multiple contiguous genes, no possible therapeutic strategies for ring chromosome disorders have so far been proposed. Our recent study (Bershteyn et al.) using patient-derived fibroblast lines containing ring chromosomes, found that cellular reprogramming of these fibroblasts into induced pluripotent stem cells (iPSCs) resulted in the cell-autonomous correction of the ring chromosomal aberration via compensatory uniparental disomy (UPD). These observations have important implications for studying the mechanism of chromosomal number control and may lead to the development of effective therapies for other, more common, chromosomal aberrations.

  13. Chromosome therapy. Correction of large chromosomal aberrations by inducing ring chromosomes in induced pluripotent stem cells (iPSCs).

    PubMed

    Kim, Taehyun; Bershteyn, Marina; Wynshaw-Boris, Anthony

    2014-01-01

    The fusion of the short (p) and long (q) arms of a chromosome is referred to as a "ring chromosome." Ring chromosome disorders occur in approximately 1 in 50,000-100,000 patients. Ring chromosomes can result in birth defects, mental disabilities, and growth retardation if additional genes are deleted during the formation of the ring. Due to the severity of these large-scale aberrations affecting multiple contiguous genes, no possible therapeutic strategies for ring chromosome disorders have so far been proposed. Our recent study (Bershteyn et al.) using patient-derived fibroblast lines containing ring chromosomes, found that cellular reprogramming of these fibroblasts into induced pluripotent stem cells (iPSCs) resulted in the cell-autonomous correction of the ring chromosomal aberration via compensatory uniparental disomy (UPD). These observations have important implications for studying the mechanism of chromosomal number control and may lead to the development of effective therapies for other, more common, chromosomal aberrations. PMID:25482192

  14. Aberrant Pulmonary Vascular Growth and Remodeling in Bronchopulmonary Dysplasia

    PubMed Central

    Alvira, Cristina M.

    2016-01-01

    In contrast to many other organs, a significant portion of lung development occurs after birth during alveolarization, thus rendering the lung highly susceptible to injuries that may disrupt this developmental process. Premature birth heightens this susceptibility, with many premature infants developing the chronic lung disease, bronchopulmonary dysplasia (BPD), a disease characterized by arrested alveolarization. Over the past decade, tremendous progress has been made in the elucidation of mechanisms that promote postnatal lung development, including extensive data suggesting that impaired pulmonary angiogenesis contributes to the pathogenesis of BPD. Moreover, in addition to impaired vascular growth, patients with BPD also frequently demonstrate alterations in pulmonary vascular remodeling and tone, increasing the risk for persistent hypoxemia and the development of pulmonary hypertension. In this review, an overview of normal lung development will be presented, and the pathologic features of arrested development observed in BPD will be described, with a specific emphasis on the pulmonary vascular abnormalities. Key pathways that promote normal pulmonary vascular development will be reviewed, and the experimental and clinical evidence demonstrating alterations of these essential pathways in BPD summarized. PMID:27243014

  15. Aberrant Levels of Hematopoietic/Neuronal Growth and Differentiation Factors in Euthyroid Women at Risk for Autoimmune Thyroid Disease

    PubMed Central

    Massolt, Elske T.; Effraimidis, Grigoris; Korevaar, Tim I. M.; Wiersinga, Wilmar M.; Visser, W. Edward; Peeters, Robin P.; Drexhage, Hemmo A.

    2016-01-01

    Background Subjects at risk for major mood disorders have a higher risk to develop autoimmune thyroid disease (AITD) and vice-versa, implying a shared pathogenesis. In mood disorder patients, an abnormal profile of hematopoietic/neuronal growth factors is observed, suggesting that growth/differentiation abnormalities of these cell lineages may predispose to mood disorders. The first objective of our study was to investigate whether an aberrant profile of these hematopoietic/neuronal growth factors is also detectable in subjects at risk for AITD. A second objective was to study the inter relationship of these factors with previously determined and published growth factors/cytokines in the same subjects. Methods We studied 64 TPO-Ab-negative females with at least 1 first- or second-degree relative with AITD, 32 of whom did and 32 who did not seroconvert to TPO-Ab positivity in 5-year follow-up. Subjects were compared with 32 healthy controls (HCs). We measured serum levels of brain-derived neurotrophic factor (BDNF), Stem Cell Factor (SCF), Insulin-like Growth Factor-Binding Protein 2 (IGFBP-2), Epidermal Growth Factor (EGF) and IL-7 at baseline. Results BDNF was significantly lower (8.2 vs 18.9 ng/ml, P<0.001), while EGF (506.9 vs 307.6 pg/ml, P = 0.003) and IGFBP-2 (388.3 vs 188.5 ng/ml, P = 0.028) were significantly higher in relatives than in HCs. Relatives who seroconverted in the next 5 years had significantly higher levels of SCF than non-seroconverters (26.5 vs 16.7 pg/ml, P = 0.017). In a cluster analysis with the previously published growth factors/cytokines SCF clustered together with IL-1β, IL-6 and CCL-3, of which high levels also preceded seroconversion. Conclusion Relatives of AITD patients show aberrant serum levels of 4 hematopoietic/neuronal growth factors similar to the aberrancies found in mood disorder patients, suggesting that shared growth and differentiation defects in both the hematopoietic and neuronal system may underlie thyroid

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

    NASA Technical Reports Server (NTRS)

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

    2011-01-01

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

  17. Cytogenetic profiles in multiple myeloma and monoclonal gammopathy of undetermined significance: a study in highly purified aberrant plasma cells

    PubMed Central

    Schmidt-Hieber, Martin; Gutiérrez, María Laura; Pérez-Andrés, Martin; Paiva, Bruno; Rasillo, Ana; Tabernero, Maria Dolores; Sayagués, José Maria; Lopez, Antonio; Bárcena, Paloma; Sanchez, María Luz; Gutiérrez, Norma C.; San Miguel, Jesus F.; Orfao, Alberto

    2013-01-01

    Cytogenetic studies in clonal plasma cell disorders have mainly been done in whole bone marrow or CD138+ microbead-enriched plasma cells and suggest that recurrent immunoglobulin heavy chain translocations - e.g. t(4;14) -are primary oncogenetic events. The aim of this study was to determine cytogenetic patterns of highly purified aberrant plasma cells (median purity ≥98%) in different clonal plasma cell disorders. We analyzed aberrant plasma cells from 208 patients with multiple myeloma (n=148) and monoclonal gammopathy of undetermined significance (n=60) for the presence of del(13q14), del(17p13) and t(14q32) using multicolor interphase fluorescence in situ hybridization. Additionally, immunoglobulin heavy chain gene arrangements were analyzed and complementarity determining region 3 was sequenced in a subset of patients and combined multicolor interphase fluorescence in situ hybridization/immunofluorescent protein staining analyses were performed in selected cases to confirm clonality and cytogenetic findings. At diagnosis, 96% of cases with multiple myeloma versus 77% of monoclonal gammopathy of undetermined significance cases showed at least one cytogenetic alteration and/or hyperdiploidy. The cytogenetic heterogeneity of individual cases reflected coexistence of cytogenetically-defined aberrant plasma cell clones, and led to the assumption that karyotypic alterations were acquired stepwise. Cases of multiple myeloma and monoclonal gammopathy of undetermined significance frequently showed different but related cytogenetic profiles when other cytogenetic alterations such as deletions/gains of the immunoglobulin heavy chain or the fibroblast growth factor receptor 3 were additionally considered. Interestingly, in 24% of multiple myeloma versus 62% of monoclonal gammopathy of undetermined significance patients with an immunoglobulin heavy chain translocation, aberrant plasma cells with and without t(14q32) coexisted in the same patient. Our data suggest that

  18. Fibroblast growth factor family aberrations in cancers: clinical and molecular characteristics.

    PubMed

    Parish, A; Schwaederle, M; Daniels, G; Piccioni, D; Fanta, P; Schwab, R; Shimabukuro, K; Parker, B A; Helsten, T; Kurzrock, R

    2015-01-01

    Fibroblast growth factor ligands and receptors (FGF and FGFR) play critical roles in tumorigenesis, and several drugs have been developed to target them. We report the biologic correlates of FGF/FGFR abnormalities in diverse malignancies. The medical records of patients with cancers that underwent targeted next generation sequencing (182 or 236 cancer-related genes) were reviewed. The following FGF/FGFR genes were tested: FGF3, 4, 6, 7, 10, 12, 14, 19, 23 and FGFR1, 2, 3, and 4. Of 391 patients, 56 (14.3%) had aberrant FGF (N = 38, all amplifications) and/or FGFR (N = 22 including 5 mutations and one FGFR3-TACC3 fusion). FGF/FGFR aberrations were most frequent in breast cancers (26/81, 32.1%, p = 0.0003). In multivariate analysis, FGF/FGFR abnormalities were independently associated with CCND1/2, RICTOR, ZNF703, RPTOR, AKT2, and CDK8 alterations (all P < 0.02), as well as with an increased median number of alterations (P < 0.0001). FGF3, FGF4, FGF19 and CCND1 were co-amplified in 22 of 391 patients (5.6%, P < 0.0001), most likely because they co-localize on the same chromosomal region (11q13). There was no significant difference in time to metastasis or overall survival when comparing patients harboring FGF/FGFR alterations versus those not. Overall, FGF/FGFR was one of the most frequently aberrant pathways in our population comprising patients with diverse malignancies. These aberrations frequently co-exist with anomalies in a variety of other genes, suggesting that tailored combination therapy may be necessary in these patients. PMID:25950492

  19. Fibroblast growth factor family aberrations in cancers: clinical and molecular characteristics

    PubMed Central

    Parish, A; Schwaederle, M; Daniels, G; Piccioni, D; Fanta, P; Schwab, R; Shimabukuro, K; Parker, BA; Helsten, T; Kurzrock, R

    2015-01-01

    Fibroblast growth factor ligands and receptors (FGF and FGFR) play critical roles in tumorigenesis, and several drugs have been developed to target them. We report the biologic correlates of FGF/FGFR abnormalities in diverse malignancies. The medical records of patients with cancers that underwent targeted next generation sequencing (182 or 236 cancer-related genes) were reviewed. The following FGF/FGFR genes were tested: FGF3, 4, 6, 7, 10, 12, 14, 19, 23 and FGFR1, 2, 3, and 4. Of 391 patients, 56 (14.3%) had aberrant FGF (N = 38, all amplifications) and/or FGFR (N = 22 including 5 mutations and one FGFR3-TACC3 fusion). FGF/FGFR aberrations were most frequent in breast cancers (26/81, 32.1%, p = 0.0003). In multivariate analysis, FGF/FGFR abnormalities were independently associated with CCND1/2, RICTOR, ZNF703, RPTOR, AKT2, and CDK8 alterations (all P < 0.02), as well as with an increased median number of alterations (P < 0.0001). FGF3, FGF4, FGF19 and CCND1 were co-amplified in 22 of 391 patients (5.6%, P < 0.0001), most likely because they co-localize on the same chromosomal region (11q13). There was no significant difference in time to metastasis or overall survival when comparing patients harboring FGF/FGFR alterations versus those not. Overall, FGF/FGFR was one of the most frequently aberrant pathways in our population comprising patients with diverse malignancies. These aberrations frequently co-exist with anomalies in a variety of other genes, suggesting that tailored combination therapy may be necessary in these patients. PMID:25950492

  20. Fibroblast growth factor family aberrations in cancers: clinical and molecular characteristics.

    PubMed

    Parish, A; Schwaederle, M; Daniels, G; Piccioni, D; Fanta, P; Schwab, R; Shimabukuro, K; Parker, B A; Helsten, T; Kurzrock, R

    2015-01-01

    Fibroblast growth factor ligands and receptors (FGF and FGFR) play critical roles in tumorigenesis, and several drugs have been developed to target them. We report the biologic correlates of FGF/FGFR abnormalities in diverse malignancies. The medical records of patients with cancers that underwent targeted next generation sequencing (182 or 236 cancer-related genes) were reviewed. The following FGF/FGFR genes were tested: FGF3, 4, 6, 7, 10, 12, 14, 19, 23 and FGFR1, 2, 3, and 4. Of 391 patients, 56 (14.3%) had aberrant FGF (N = 38, all amplifications) and/or FGFR (N = 22 including 5 mutations and one FGFR3-TACC3 fusion). FGF/FGFR aberrations were most frequent in breast cancers (26/81, 32.1%, p = 0.0003). In multivariate analysis, FGF/FGFR abnormalities were independently associated with CCND1/2, RICTOR, ZNF703, RPTOR, AKT2, and CDK8 alterations (all P < 0.02), as well as with an increased median number of alterations (P < 0.0001). FGF3, FGF4, FGF19 and CCND1 were co-amplified in 22 of 391 patients (5.6%, P < 0.0001), most likely because they co-localize on the same chromosomal region (11q13). There was no significant difference in time to metastasis or overall survival when comparing patients harboring FGF/FGFR alterations versus those not. Overall, FGF/FGFR was one of the most frequently aberrant pathways in our population comprising patients with diverse malignancies. These aberrations frequently co-exist with anomalies in a variety of other genes, suggesting that tailored combination therapy may be necessary in these patients.

  1. Pancreatic Tumor Cell Secreted CCN1/Cyr61 Promotes Endothelial cell migration and Aberrant Neovascularization

    PubMed Central

    Maity, Gargi; Mehta, Smita; Haque, Inamul; Dhar, Kakali; Sarkar, Sandipto; Banerjee, Sushanta K.; Banerjee, Snigdha

    2014-01-01

    The complex signaling networks between cancer cells and adjacent endothelial cells make it challenging to unravel how cancer cells send extracellular messages to promote aberrant vascularization or tumor angiogenesis. Here, in vitro and in vivo models show that pancreatic cancer cell generated unique microenvironments can underlie endothelial cell migration and tumor angiogenesis. Mechanistically, we find that pancreatic cancer cell secreted CCN1/Cyr61 matricellular protein rewires the microenvironment to promote endothelial cell migration and tumor angiogenesis. This event can be overcome by Sonic Hedgehog (SHh) antibody treatment. Collectively, these studies identify a novel CCN1 signaling program in pancreatic cancer cells which activates SHh through autocrine-paracrine circuits to promote endothelial cell migration and tumor angiogenesis and suggests that CCN1 signaling of pancreatic cancer cells is vital for the regulation of tumor angiogenesis. Thus CCN1 signaling could be an ideal target for tumor vascular disruption in pancreatic cancer. PMID:24833309

  2. Induction of chromosomal aberrations by propoxur in mouse bone marrow cells.

    PubMed

    Agrawal, R C

    1999-12-01

    Propoxur is a widely used dithiocarbamate insecticide. In this study, the clastogenic effect of propoxur has been evaluated using chromosomal aberration assay in mouse bone marrow cells. Single i.p. administration of propoxur, at 25 mg/kg b.wt., a maximum tolerated dose (MTD) and 12.5 mg/kg b.wt (50% of MTD) have significantly induced different types of aberrations after 24 h of treatment. The aberrations were dose and time dependent and reached a maximum after 24 h of exposure. The results suggest a genotoxic potential of propoxur.

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

    NASA Technical Reports Server (NTRS)

    Wu, Honglu

    2006-01-01

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

  4. Tumor-derived endothelial cells exhibit aberrant Rho-mediated mechanosensing and abnormal angiogenesis in vitro.

    PubMed

    Ghosh, Kaustabh; Thodeti, Charles K; Dudley, Andrew C; Mammoto, Akiko; Klagsbrun, Michael; Ingber, Donald E

    2008-08-12

    Tumor blood vessels exhibit abnormal structure and function that cause disturbed blood flow and high interstitial pressure, which impair delivery of anti-cancer agents. Past efforts to normalize the tumor vasculature have focused on inhibition of soluble angiogenic factors, such as VEGF; however, capillary endothelial (CE) cell growth and differentiation during angiogenesis are also influenced by mechanical forces conveyed by the extracellular matrix (ECM). Here, we explored the possibility that tumor CE cells form abnormal vessels because they lose their ability to sense and respond to these physical cues. These studies reveal that, in contrast to normal CE cells, tumor-derived CE cells fail to reorient their actin cytoskeleton when exposed to uniaxial cyclic strain, exhibit distinct shape sensitivity to variations in ECM elasticity, exert greater traction force, and display an enhanced ability to retract flexible ECM substrates and reorganize into tubular networks in vitro. These behaviors correlate with a constitutively high level of baseline activity of the small GTPase Rho and its downstream effector, Rho-associated kinase (ROCK). Moreover, decreasing Rho-mediated tension by using the ROCK inhibitor, Y27632, can reprogram the tumor CE cells so that they normalize their reorientation response to uniaxial cyclic strain and their ability to form tubular networks on ECM gels. Abnormal Rho-mediated sensing of mechanical cues in the tumor microenvironment may therefore contribute to the aberrant behaviors of tumor CE cells that result in the development of structural abnormalities in the cancer microvasculature.

  5. Mechanisms of formation of chromosomal aberrations: insights from studies with DNA repair-deficient cells.

    PubMed

    Palitti, F

    2004-01-01

    In order to understand the mechanisms of formation of chromosomal aberrations, studies performed on human syndromes with genomic instability can be fruitful. In this report, the results from studies in our laboratory on the importance of the transcription-coupled repair (TCR) pathway on the induction of chromosomal damage and apoptosis by ultraviolet light (UV) are discussed. UV61 cells (hamster homologue of human Cockayne's syndrome group B) deficient in TCR showed a dramatic increase in the induction of chromosomal aberrations and apoptosis following UV treatment. At relatively low UV doses, the induction of chromosomal aberrations preceded the apoptotic process. Chromosomal aberrations probably lead to apoptosis and most of the cells had gone through an S phase after the UV treatment before entering apoptosis. At higher doses of UV, the cells could go into apoptosis already in the G1 phase of the cell cycle. Abolition of TCR by treatment with alpha-amanitin (an inhibitor of RNA polymerase II) in the parental cell line AA8 also resulted in the induction of elevated chromosomal damage and apoptotic response similar to the one observed in UV61 cells treated with UV alone. This suggests that the lack of TCR is responsible for the increased frequencies of chromosomal aberrations and apoptosis in UV61 cells. Hypersensitivity to the induction of chromosomal damage by inhibitors of antitopoisomerases I and II in Werner's syndrome cells is also discussed in relation to the compromised G2 phase processes involving the Werner protein. PMID:15162020

  6. Aberrant Lipid Metabolism Promotes Prostate Cancer: Role in Cell Survival under Hypoxia and Extracellular Vesicles Biogenesis

    PubMed Central

    Deep, Gagan; Schlaepfer, Isabel R.

    2016-01-01

    Prostate cancer (PCa) is the leading malignancy among men in United States. Recent studies have focused on the identification of novel metabolic characteristics of PCa, aimed at devising better preventive and therapeutic approaches. PCa cells have revealed unique metabolic features such as higher expression of several enzymes associated with de novo lipogenesis, fatty acid up-take and β-oxidation. This aberrant lipid metabolism has been reported to be important for PCa growth, hormone-refractory progression and treatment resistance. Furthermore, PCa cells effectively use lipid metabolism under adverse environmental conditions for their survival advantage. Specifically, hypoxic cancer cells accumulate higher amount of lipids through a combination of metabolic alterations including high glutamine and fatty acid uptake, as well as decreased fatty acid oxidation. These stored lipids serve to protect cancer cells from oxidative and endoplasmic reticulum stress, and play important roles in fueling cancer cell proliferation following re-oxygenation. Lastly, cellular lipids have also been implicated in extracellular vesicle biogenesis, which play a vital role in intercellular communication. Overall, the new understanding of lipid metabolism in recent years has offered several novel targets to better target and manage clinical PCa. PMID:27384557

  7. Aberrant Lipid Metabolism Promotes Prostate Cancer: Role in Cell Survival under Hypoxia and Extracellular Vesicles Biogenesis.

    PubMed

    Deep, Gagan; Schlaepfer, Isabel R

    2016-01-01

    Prostate cancer (PCa) is the leading malignancy among men in United States. Recent studies have focused on the identification of novel metabolic characteristics of PCa, aimed at devising better preventive and therapeutic approaches. PCa cells have revealed unique metabolic features such as higher expression of several enzymes associated with de novo lipogenesis, fatty acid up-take and β-oxidation. This aberrant lipid metabolism has been reported to be important for PCa growth, hormone-refractory progression and treatment resistance. Furthermore, PCa cells effectively use lipid metabolism under adverse environmental conditions for their survival advantage. Specifically, hypoxic cancer cells accumulate higher amount of lipids through a combination of metabolic alterations including high glutamine and fatty acid uptake, as well as decreased fatty acid oxidation. These stored lipids serve to protect cancer cells from oxidative and endoplasmic reticulum stress, and play important roles in fueling cancer cell proliferation following re-oxygenation. Lastly, cellular lipids have also been implicated in extracellular vesicle biogenesis, which play a vital role in intercellular communication. Overall, the new understanding of lipid metabolism in recent years has offered several novel targets to better target and manage clinical PCa. PMID:27384557

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

    PubMed Central

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

    2016-01-01

    Donor T-cell immune responses can eradicate lymphomas after allogeneic hematopoietic stem cell transplantation (AHSCT), but can also damage healthy tissues resulting in harmful graft-versus-host disease (GVHD). Next-generation sequencing has recently identified many new genetic lesions in follicular lymphoma (FL). One such gene, tumor necrosis factor receptor superfamily 14 (TNFRSF14), abnormal in 40% of FL patients, encodes the herpes virus entry mediator (HVEM) which limits T-cell activation via ligation of the B- and T-lymphocyte attenuator. As lymphoma B cells can act as antigen-presenting cells, we hypothesized that TNFRSF14 aberrations that reduce HVEM expression could alter the capacity of FL B cells to stimulate allogeneic T-cell responses and impact the outcome of AHSCT. In an in vitro model of alloreactivity, human lymphoma B cells with TNFRSF14 aberrations had reduced HVEM expression and greater alloantigen-presenting capacity than wild-type lymphoma B cells. The increased immune-stimulatory capacity of lymphoma B cells with TNFRSF14 aberrations had clinical relevance, associating with higher incidence of acute GVHD in patients undergoing AHSCT. FL patients with TNFRSF14 aberrations may benefit from more aggressive immunosuppression to reduce harmful GVHD after transplantation. Importantly, this study is the first to demonstrate the impact of an acquired genetic lesion on the capacity of tumor cells to stimulate allogeneic T-cell immune responses which may have wider consequences for adoptive immunotherapy strategies. PMID:27103745

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

    NASA Technical Reports Server (NTRS)

    Lu, Tao; Zhang, Ye; Yeshitla, Samrawit; Bowler, Deborah; Kadhim, Munira; Wilson, Bobby; Wu, Honglu

    2016-01-01

    Genomic instability, induced by various metabolic, genetic, and environmental factors, is the driving force of tumorigenesis. Radiation exposure from different types of radiation sources induces different types of DNA damages, increases mutation and chromosome aberration rates, and increases cellular transformation in vitro and in vivo experiments. The cell survival rates and frequency of chromosome aberrations depend on the genetic background and radiation sources. To further understand genomic instability induced by charged particles, we exposed human lymphocytes ex vivo, human fibroblast cells, human mammary epithelial cells, and bone marrow cells isolated from CBA/CaH and C57BL/6 mice to high energy protons and Fe ions, and collected chromosomes at different generations after exposure. Chromosome aberrations were analyzed with fluorescent in situ hybridization with whole chromosome specific probes.

  10. Fetal deficiency of lin28 programs life-long aberrations in growth and glucose metabolism.

    PubMed

    Shinoda, Gen; Shyh-Chang, Ng; Soysa, T Yvanka de; Zhu, Hao; Seligson, Marc T; Shah, Samar P; Abo-Sido, Nora; Yabuuchi, Akiko; Hagan, John P; Gregory, Richard I; Asara, John M; Cantley, Lewis C; Moss, Eric G; Daley, George Q

    2013-08-01

    LIN28A/B are RNA binding proteins implicated by genetic association studies in human growth and glucose metabolism. Mice with ectopic over-expression of Lin28a have shown related phenotypes. Here, we describe the first comprehensive analysis of the physiologic consequences of Lin28a and Lin28b deficiency in knockout (KO) mice. Lin28a/b-deficiency led to dwarfism starting at different ages, and compound gene deletions showed a cumulative dosage effect on organismal growth. Conditional gene deletion at specific developmental stages revealed that fetal but neither neonatal nor adult deficiency resulted in growth defects and aberrations in glucose metabolism. Tissue-specific KO mice implicated skeletal muscle-deficiency in the abnormal programming of adult growth and metabolism. The effects of Lin28b KO could be rescued by Tsc1 haplo-insufficiency in skeletal muscles. Our data implicate fetal expression of Lin28a/b in the regulation of life-long effects on metabolism and growth, and demonstrate that fetal Lin28b acts at least in part via mTORC1 signaling.

  11. Imaging nanometre-scale structure in cells using in situ aberration correction.

    PubMed

    Fuller, C J; Straight, A F

    2012-10-01

    Accurate distance measurements of cellular structures on a length scale relevant to single macromolecules or macromolecular complexes present a major challenge for biological microscopy. In addition to the inherent challenges of overcoming the limits imposed by the diffraction of light, cells themselves are a complex and poorly understood optical environment. We present an extension of the high-resolution colocalization method to measure three dimensional distances between diffraction-limited objects using standard widefield fluorescence microscopy. We use this method to demonstrate that in three dimensions, cells intrinsically introduce a large and variable amount of chromatic aberration into optical measurements. We present a means of correcting this aberration in situ [termed 'Colocalization and In-situ Correction of Aberration for Distance Analysis' (CICADA)] by exploiting the fact that there is a linear relationship between the degree of aberration between different wavelengths. By labelling a cellular structure with redundantly multi-colour labelled antibodies, we can create an intracellular fiducial marker for correcting the individual aberrations between two different wavelengths in the same cells. Our observations demonstrate that with suitable corrections, nanometre scale three-dimensional distance measurements can be used to probe the substructure of macromolecular complexes within cells.

  12. Aberrant mural cell recruitment to lymphatic vessels and impaired lymphatic drainage in a murine model of pulmonary fibrosis.

    PubMed

    Meinecke, Anna-Katharina; Nagy, Nadine; Lago, Gabriela D'Amico; Kirmse, Santina; Klose, Ralph; Schrödter, Katrin; Zimmermann, Annika; Helfrich, Iris; Rundqvist, Helene; Theegarten, Dirk; Anhenn, Olaf; Orian-Rousseau, Véronique; Johnson, Randall S; Alitalo, Kari; Fischer, Jens W; Fandrey, Joachim; Stockmann, Christian

    2012-06-14

    Pulmonary fibrosis is a progressive disease with unknown etiology that is characterized by extensive remodeling of the lung parenchyma, ultimately resulting in respiratory failure. Lymphatic vessels have been implicated with the development of pulmonary fibrosis, but the role of the lymphatic vasculature in the pathogenesis of pulmonary fibrosis remains enigmatic. Here we show in a murine model of pulmonary fibrosis that lymphatic vessels exhibit ectopic mural coverage and that this occurs early during the disease. The abnormal lymphatic vascular patterning in fibrotic lungs was driven by expression of platelet-derived growth factor B (PDGF-B) in lymphatic endothelial cells and signaling through platelet-derived growth factor receptor (PDGFR)-β in associated mural cells. Because of impaired lymphatic drainage, aberrant mural cell coverage fostered the accumulation of fibrogenic molecules and the attraction of fibroblasts to the perilymphatic space. Pharmacologic inhibition of the PDGF-B/PDGFR-β signaling axis disrupted the association of mural cells and lymphatic vessels, improved lymphatic drainage of the lung, and prevented the attraction of fibroblasts to the perilymphatic space. Our results implicate aberrant mural cell recruitment to lymphatic vessels in the pathogenesis of pulmonary fibrosis and that the drainage capacity of pulmonary lymphatics is a critical mediator of fibroproliferative changes.

  13. TGF-{beta}-stimulated aberrant expression of class III {beta}-tubulin via the ERK signaling pathway in cultured retinal pigment epithelial cells

    SciTech Connect

    Chung, Eun Jee; Chun, Ji Na; Jung, Sun-Ah; Cho, Jin Won; Lee, Joon H.

    2011-11-18

    Highlights: Black-Right-Pointing-Pointer TGF-{beta} induces aberrant expression of {beta}III in RPE cells via the ERK pathway. Black-Right-Pointing-Pointer TGF-{beta} increases O-GlcNAc modification of {beta}III in RPE cells. Black-Right-Pointing-Pointer Mature RPE cells have the capacity to express a neuron-associated gene by TGF-{beta}. -- Abstract: The class III {beta}-tubulin isotype ({beta}{sub III}) is expressed exclusively by neurons within the normal human retina and is not present in normal retinal pigment epithelial (RPE) cells in situ or in the early phase of primary cultures. However, aberrant expression of class III {beta}-tubulin has been observed in passaged RPE cells and RPE cells with dedifferentiated morphology in pathologic epiretinal membranes from idiopathic macular pucker, proliferative vitreoretinopathy (PVR) and proliferative diabetic retinopathy (PDR). Transforming growth factor-{beta} (TGF-{beta}) has been implicated in dedifferentiation of RPE cells and has a critical role in the development of proliferative vitreoretinal diseases. Here, we investigated the potential effects of TGF-{beta} on the aberrant expression of class III {beta}-tubulin and the intracellular signaling pathway mediating these changes. TGF-{beta}-induced aberrant expression and O-linked-{beta}-N-acetylglucosamine (O-GlcNac) modification of class III {beta}-tubulin in cultured RPE cells as determined using Western blotting, RT-PCR and immunocytochemistry. TGF-{beta} also stimulated phosphorylation of ERK. TGF-{beta}-induced aberrant expression of class III {beta}-tubulin was significantly reduced by pretreatment with U0126, an inhibitor of ERK phosphorylation. Our findings indicate that TGF-{beta} stimulated aberrant expression of class III {beta}-tubulin via activation of the ERK signaling pathway. These data demonstrate that mature RPE cells have the capacity to express a neuron-associated gene in response to TGF-{beta} stimulation and provide useful information

  14. Frequency of Early and Late Chromosome Aberrations in Different Types of Cells After Proton and Fe Ion Irradiation

    NASA Astrophysics Data System (ADS)

    Lu, Tao; Wu, Honglu; Zhang, Ye; Yeshitla, Samrawit; Kadhim, Munira; Wilson, Bobby; Bowler, Deborah

    2016-07-01

    DNA damages induced by space radiation, consisting of protons and high-LET charged particles, can be complex in nature, which are often left unrepaired and cause chromosomal aberrations. Increased level of genomic instability is attributed to tumorigenesis and increased cancer risks. To investigate genomic instability induced by charged particles, human lymphocytes ex vivo, human fibroblasts, and human mammary epithelial cells, as well as mouse bone marrow stem cells isolated from CBA/CaH and C57BL/6 strains were exposed to high energy protons and Fe ions. Metaphase chromosome spreads at different cell divisions after radiation exposure were collected and, chromosome aberrations were analyzed with fluorescence in situ hybridization with whole chromosome-specific probes for human cells. With proton irradiation, levels of chromosome aberrations decreased by about 50% in both lymphocytes and epithelial cells after multiple cell divisions, compared to initial chromosome aberrations at 48 hours post irradiation in both cell types. With Fe ion irradiation, however, the frequency of chromosome aberrations in lymphocytes after multiple cell divisions was significantly lower than that in epithelial cells at comparable cell divisions, while their initial chromosome aberrations were at similar levels. Similar to the human cells, after Fe ion irradiation, the frequency of late chromosome aberrations was similar to that of the early damages for radio-sensitive CBA cells, but different for radio-resistant C57 cells. Our results suggest that relative biological effectiveness (RBE) values are dependent not only on radiation sources, but also on cell types and cell divisions.

  15. Frequency of Early and Late Chromosome Aberrations in Different Types of Cells After Proton and Fe Ion Irradiation

    NASA Technical Reports Server (NTRS)

    Lu, Tao; Zhang, Ye; Yeshitla, Samrawit; Bowler, Deborah; Kadhim, Munira; Wilson, Bobby; Wu, Honglu

    2016-01-01

    DNA damages induced by space radiation, consisting of protons and high-LET charged particles, can be complex in nature, which are often left unrepaired and cause chromosomal aberrations. Increased level of genomic instability is attributed to tumorigenesis and increased cancer risks. To investigate genomic instability induced by charged particles, human lymphocytes ex vivo, human fibroblasts, and human mammary epithelial cells, as well as mouse bone marrow stem cells isolated from CBA/CaH and C57BL/6 strains were exposed to high energy protons and Fe ions. Metaphase chromosome spreads at different cell divisions after radiation exposure were collected and, chromosome aberrations were analyzed with fluorescence in situ hybridization with whole chromosome-specific probes for human cells. With proton irradiation, levels of chromosome aberrations decreased by about 50% in both lymphocytes and epithelial cells after multiple cell divisions, compared to initial chromosome aberrations at 48 hours post irradiation in both cell types. With Fe ion irradiation, however, the frequency of chromosome aberrations in lymphocytes after multiple cell divisions was significantly lower than that in epithelial cells at comparable cell divisions, while their initial chromosome aberrations were at similar levels. Similar to the human cells, after Fe ion irradiation, the frequency of late chromosome aberrations was similar to that of the early damages for radio-sensitive CBA cells, but different for radio-resistant C57 cells. Our results suggest that relative biological effectiveness (RBE) values are dependent not only on radiation sources, but also on cell types and cell divisions.

  16. Aberrant tropoelastin secretion in MG-63 human osteosarcoma cells

    SciTech Connect

    Curtiss, S.W.

    1989-01-01

    The secretion of newly synthesized tropoelastin, the soluble precursor of the extracellular matrix protein elastin, is not well understood. MG-63 human osteosarcoma cells were found by immunoblot analysis to synthesize 62 kD and 64 kD tropoelastins. Media from 63 cells labelled for five hours with ({sup 3}H)-valine contain no detectable tropoelastin, unlike media from other tropoelastin-synthesizing cells. Immunoblots of conditioned media and 1Ox-concentrated conditioned media left on the cells for six days also show an absence of tropoelastin from the cell media. No insoluble elastin is associated with the cell layer, as determined by amino acid analysis and electron microscopy of 18-21 day cell cultures. The absence of tropoelastin from the cell medium and elastin from the extracellular matrix indicates that MG63 cells do not secrete tropoelastin as expected, but accumulate it intracellularly. This accumulation is transient: immunoblots and immunofluorescence microscopy show that cells three days after passage have the highest steady-state levels of tropoelastin per cell, that day 8 cells contain lower but still significant amounts of tropoelastin, and that by day 22 tropoelastin is no longer present in the cell cultures. Cell density is a critical factor in the observed pattern of tropoelastin expression. Cells seeded at ten fold their usual initial density have high tropoelastin levels at one day after passage, sooner than cells seeded normally. Tropoelastin also disappears from high density-seeded cells more quickly and is no longer detectable at day 10. Lysosome-like vesicles containing membranous structures appear by immunoelectron microscopy to be the primary site of intracellular tropoelastin localization.

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

    NASA Technical Reports Server (NTRS)

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

    2007-01-01

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

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

    SciTech Connect

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

    1988-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

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

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

    PubMed

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

    2015-01-01

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

  1. Induction of chromosomal aberrations in bone marrow cells of asbestotic rats

    SciTech Connect

    Fatma, N.; Khan, S.G.; Aslam, M.; Rahman, Q. )

    1992-04-01

    In the present study, cytogenetic effects of Indian chrysotile asbestos in rat bone marrow cells after 290 days of intratracheal inoculation, when it develops massive pulmonary fibrosis, were investigated. The pulmonary fibrosis was confirmed by both histopathological studies and increased collagen content in the lung of the treated animals. In the asbestotic rats a significant increase in chromosomal aberrations was recorded and a decrease in mitotic index of bone marrow cells. The types of chromosomal aberrations in these cells were chromatid gaps and breaks. The results indicate the significant cytogenetic changes in the bone marrow cells of asbestotic rats and also suggest that these changes directly or indirectly may be one of the biological events involved in eliciting the asbestos-mediated toxic responses.

  2. Aberrant amino acid signaling promotes growth and metastasis of hepatocellular carcinomas through Rab1A-dependent activation of mTORC1 by Rab1A

    PubMed Central

    Yang, Yang; Zhang, Mei-Yin; Rao, Hui-Lan; Wang, Hui-Yun; Zheng, X.F. Steven

    2015-01-01

    mTORC1 is a master regulator of cell growth and proliferation, and an established anticancer drug target. Aberrant mTORC1 signaling is common in hepatocellular carcinoma (HCC), but the underlying mechanism remains elusive. Rab1A is a newly identified mTORC1 activator that mediates an alternative amino acid (AA) signaling branch to Rag GTPases. Because liver is a physiological hub for nutrient sensing and metabolic homeostasis, we investigated the possible role of Rab1A in HCC. We found that Rab1A is frequently overexpressed in HCC, which enhances hyperactive AA-mTORC1 signaling, promoting malignant growth and metastasis of HCC in vitro and in vivo. Moreover, aberrant Rab1A expression is closely associated with poor prognosis. Strikingly, aberrant Rab1A overexpression leads to increased rapamycin sensitivity, indicating that inappropriate activation of AA signaling is a cancer-driving event in HCC. Our findings further suggest that Rab1A is a valuable biomarker for prognosis and personalized mTORC1-targeted therapy in liver cancer. PMID:26308575

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

    NASA Technical Reports Server (NTRS)

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

    2011-01-01

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

  4. Cell Growth and Division

    PubMed Central

    Bell, George I.

    1968-01-01

    In a previous paper, we proposed a model in which the volume growth rate and probability of division of a cell were assumed to be determined by the cell's age and volume. Some further mathematical implications of the model are here explored. In particular we seek properties of the growth and division functions which are required for the balanced exponential growth of a cell population. Integral equations are derived which relate the distribution of birth volumes in successive generations and in which the existence of balanced exponential growth can be treated as an eigenvalue problem. The special case in which all cells divide at the same age is treated in some detail and conditions are derived for the existence of a balanced exponential solution and for its stability or instability. The special case of growth rate proportional to cell volume is seen to have neutral stability. More generally when the division probability depends on age only and growth rate is proportional to cell volume, there is no possibility of balanced exponential growth. Some comparisons are made with experimental results. It is noted that the model permits the appearance of differentiated cells. A generalization of the model is formulated in which cells may be described by many state variables instead of just age and volume. PMID:5643273

  5. Mesenchymal stromal cells derived from acute myeloid leukemia bone marrow exhibit aberrant cytogenetics and cytokine elaboration.

    PubMed

    Huang, J C; Basu, S K; Zhao, X; Chien, S; Fang, M; Oehler, V G; Appelbaum, F R; Becker, P S

    2015-01-01

    Bone marrow-derived mesenchymal stromal cells (BM-MSCs) play a fundamental role in the BM microenvironment (BME) and abnormalities of these cells may contribute to acute myeloid leukemia (AML) pathogenesis. The aim of the study was to characterize the cytokine and gene expression profile, immunophenotype and cytogenetics of BM-MSCs from AML patients compared to normal BM-MSCs from healthy donors. AML BM-MSCs showed decreased monocyte chemoattractant protein-1 levels compared to normal BM-MSCs. AML BM-MSCs expressed similar β1 integrin, CD44, CD73, CD90 and E-cadherin compared to normal BM-MSCs. Cytogenetic analysis revealed chromosomal aberrations in AML BM-MSCs, some overlapping with and others distinct from their corresponding AML blasts. No significant difference in gene expression was detected between AML BM-MSCs compared to normal BM-MSCs; however, comparing the differences between AML and MSCs from AML patients with the differences between normal hematopoietic cells and normal MSCs by Ingenuity pathway analysis showed key distinctions of the AML setting: (1) upstream gene regulation by transforming growth factor beta 1, tumor necrosis factor, tissue transglutaminase 2, CCAAT/enhancer binding protein alpha and SWItch/Sucrose NonFermentable related, matrix associated, actin dependent regulator of chromatin, subfamily a, member 4; (2) integrin and interleukin 8 signaling as overrepresented canonical pathways; and (3) upregulation of transcription factors FBJ murine osteosarcoma viral oncogene homolog and v-myb avian myeloblastosis viral oncogene homolog. Thus, phenotypic abnormalities of AML BM-MSCs highlight a dysfunctional BME that may impact AML survival and proliferation. PMID:25860293

  6. Monitoring cell growth.

    PubMed

    Strober, W

    2001-05-01

    This appendix provides two protocols for monitoring cell growth. Counting cells using a hemacytometer is tedious but it allows one to effectively distinguish live cells from dead cells (using Trypan Blue exclusion). In addition, this procedure is less subject to errors due to cell clumping or heterogeneity of cell size. The use of an electronic cell counter is quicker and easier than counting cells using a hemacytometer. However, an electronic cell counter as currently constructed does not distinguish live from dead cells in a reliable fashion and is subject to error due to the presence of cell clumps. Overall, the electronic cell counter is best reserved for repetitive and rapid counting of fresh peripheral blood cells and should be used with caution when counting cell populations derived from tissues. PMID:18432653

  7. Persistent chromosome aberrations in the somatic cells of A-bomb survivors, Hiroshima and Nagasaki.

    PubMed

    Awa, A A

    1991-03-01

    Current status of knowledge on the radiation-induced chromosome aberrations persisting since their induction in 1945 to date in the somatic cells of A-bomb survivors in Hiroshima and Nagasaki is reviewed. Dose-response relationship for chromosome aberration frequencies observed with the use of the old A-bomb dosimetry system (T65D) is also demonstrable based on the new dosimetry system (DS86). Despite the fact that the remarkable decrease in the amount of neutron component relative to the total dose in Hiroshima, there still exist inter-city differences in aberration frequency per unit dose both for kerma and bone marrow dose; the dose-square term is smaller in Hiroshima than in Nagasaki. The differential contribution of neutron radiation may be responsible in some part for the observed difference between Hiroshima and Nagasaki, although proof still remains to be obtained. There is a wide variability of the frequency of cells with chromosome aberrations between survivors within a given dose range. Random errors in the dose estimates assigned to individual survivors seem responsible, to a large extent, for the observed overdispersions in aberration frequencies in both cities. New molecular biology-oriented techniques to differentially stain specific chromosomes using fluorescence in situ hybridization with chromosome-specific composite DNA probes seem extremely promising for future rapid, accurate and extensive screening of reciprocal translocations observed predominantly in A-bomb survivors. Such data may be utilized to establish a better biological dosimetry system, especially for those persons who are irradiated in vivo many years before cytogenetic examinations.

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

    NASA Technical Reports Server (NTRS)

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

    2014-01-01

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

  9. Frequent BCOR aberrations in extranodal NK/T-Cell lymphoma, nasal type.

    PubMed

    Dobashi, Akito; Tsuyama, Naoko; Asaka, Reimi; Togashi, Yuki; Ueda, Kyoko; Sakata, Seiji; Baba, Satoko; Sakamoto, Kana; Hatake, Kiyohiko; Takeuchi, Kengo

    2016-05-01

    Extranodal natural killer/T cell lymphoma (ENKTL) is a rare subtype of lymphoma. Recurrent mutations in the JAK-STAT pathway, recently reported in ENKTL cases, are interesting in terms of both pathogenesis and inhibitor therapy. However, the frequencies of these mutations are low and variable among reports, and other pathognomonic mutations in ENKTL remain to be elucidated. In the present study, targeted capture sequencing of 602 cancer-related genes from 25 frozen ENKTL samples was performed, 11 of which were matched to normal samples. Several recurrent somatic mutations involving BCOR (32%), TP53 (16%), DDX3X (12%), FAT4 (8%), NRAS (8%), MLL3 (12%), and MIR17HG (8%) were identified. The pattern of BCOR aberrations (1 nonsense and 5 frame-shift mutations, a mutation leading to a splicing error, and gene loss) suggested that loss of function of BCOR was the functionally important outcome of such changes. The literature was reviewed and the public data on BCOR aberrations was reanalyzed and it was found that the aberrations were frequently found in myeloid neoplasms, but, interestingly, were highly specific to ENKTL among lymphoid malignancies. Given the high frequency and pattern of aberration, BCOR is likely to play an important role in ENKTL pathogenesis as a tumor suppressor gene. PMID:26773734

  10. Identification of Targetable HER2 Aberrations in Head and Neck Squamous Cell Carcinoma

    PubMed Central

    Birkeland, Andrew C.; Yanik, Megan; Tillman, Brittny N.; Scott, Megan V.; Foltin, Susan K.; Mann, Jacqueline E.; Michmerhuizen, Nicole L.; Ludwig, Megan L.; Sandelski, Morgan M.; Komarck, Christine M.; Carey, Thomas E.; Prince, Mark E.P.; Bradford, Carol R.; McHugh, Jonathan B.; Spector, Matthew E.; Brenner, J. Chad

    2016-01-01

    Importance HER2 is an important drug target in breast cancer, where anti-HER2 therapy has been shown to lead to improvements in disease recurrence and overall survival. HER2 status in head and neck squamous cell carcinoma (HNSCC) has not been well studied. Identification of HER2 positive tumors and characterization of response to HER2 therapy could lead to targeted treatment options in HNSCC. Objective To identify HER2 aberrations in HNSCCs and investigate potential for HER2 targeted therapy in HNSCCs. Design, Setting, and Participants Retrospective case series of patients with laryngeal and oral cavity SCC enrolled in the University of MichiganSPORE. Publically available sequencing data(TCGA) was reviewed to identify additional mutations and overexpression in HER2 in HNSCC. Established HNSCC cell lines were used for follow-up in vitro analysis. Interventions Using targeted, amplicon-based sequencing with the Oncomine Cancer Panel, we assessed the copy number and mutation status of commonly altered genes in HNSCCs. Immunohistochemical staining was performed on tissue microarrays of HNSCCs to assess expression of HER2. Western blotting for HNSCC cell line HER2 expression, and cell survival assays after treatment with HER2 inhibitors were performed. Main Outcomes and Measures Prevalence of HER2 genetic aberrations and HER2 overexpression in laryngeal and oral cavity squamous cell carcinomas (SCCs). Prevalence of HER2 aberrations in HNSCC in TCGA. HER2 protein expression in HNSCC cell lines. Response of HNSCC cell lines to targeted HER2 inhibitors. Results Forty-two laryngeal SCC samples were screened by targeted sequencing, of which 4 were positive for HER2 amplification. Two samples identified with sequencing showed HER2 overexpression on immunohistochemistry. Two of 94 oral cavity SCC samples were positive for HER2 on immunohistochemistry. Analysis of 288 patients from publicly available HNSCC sequencing data revealed 9 amplifications in HER2. Protein expression

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

    NASA Technical Reports Server (NTRS)

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

    2009-01-01

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

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

    NASA Technical Reports Server (NTRS)

    Wu, Honglu; Hada, Megumi; Cucinotta, Francis

    2007-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    2015-01-01

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

  14. Aberrant DNA methylation in non-small cell lung cancer-associated fibroblasts.

    PubMed

    Vizoso, Miguel; Puig, Marta; Carmona, F Javier; Maqueda, María; Velásquez, Adriana; Gómez, Antonio; Labernadie, Anna; Lugo, Roberto; Gabasa, Marta; Rigat-Brugarolas, Luis G; Trepat, Xavier; Ramírez, Josep; Moran, Sebastian; Vidal, Enrique; Reguart, Noemí; Perera, Alexandre; Esteller, Manel; Alcaraz, Jordi

    2015-12-01

    Epigenetic changes through altered DNA methylation have been implicated in critical aspects of tumor progression, and have been extensively studied in a variety of cancer types. In contrast, our current knowledge of the aberrant genomic DNA methylation in tumor-associated fibroblasts (TAFs) or other stromal cells that act as critical coconspirators of tumor progression is very scarce. To address this gap of knowledge, we conducted genome-wide DNA methylation profiling on lung TAFs and paired control fibroblasts (CFs) from non-small cell lung cancer patients using the HumanMethylation450 microarray. We found widespread DNA hypomethylation concomitant with focal gain of DNA methylation in TAFs compared to CFs. The aberrant DNA methylation landscape of TAFs had a global impact on gene expression and a selective impact on the TGF-β pathway. The latter included promoter hypermethylation-associated SMAD3 silencing, which was associated with hyperresponsiveness to exogenous TGF-β1 in terms of contractility and extracellular matrix deposition. In turn, activation of CFs with exogenous TGF-β1 partially mimicked the epigenetic alterations observed in TAFs, suggesting that TGF-β1 may be necessary but not sufficient to elicit such alterations. Moreover, integrated pathway-enrichment analyses of the DNA methylation alterations revealed that a fraction of TAFs may be bone marrow-derived fibrocytes. Finally, survival analyses using DNA methylation and gene expression datasets identified aberrant DNA methylation on the EDARADD promoter sequence as a prognostic factor in non-small cell lung cancer patients. Our findings shed light on the unique origin and molecular alterations underlying the aberrant phenotype of lung TAFs, and identify a stromal biomarker with potential clinical relevance. PMID:26449251

  15. Aberrant DNA methylation in non-small cell lung cancer-associated fibroblasts

    PubMed Central

    Vizoso, Miguel; Puig, Marta; Carmona, F.Javier; Maqueda, María; Velásquez, Adriana; Gómez, Antonio; Labernadie, Anna; Lugo, Roberto; Gabasa, Marta; Rigat-Brugarolas, Luis G.; Trepat, Xavier; Ramírez, Josep; Moran, Sebastian; Vidal, Enrique; Reguart, Noemí; Perera, Alexandre; Esteller, Manel; Alcaraz, Jordi

    2015-01-01

    Epigenetic changes through altered DNA methylation have been implicated in critical aspects of tumor progression, and have been extensively studied in a variety of cancer types. In contrast, our current knowledge of the aberrant genomic DNA methylation in tumor-associated fibroblasts (TAFs) or other stromal cells that act as critical coconspirators of tumor progression is very scarce. To address this gap of knowledge, we conducted genome-wide DNA methylation profiling on lung TAFs and paired control fibroblasts (CFs) from non-small cell lung cancer patients using the HumanMethylation450 microarray. We found widespread DNA hypomethylation concomitant with focal gain of DNA methylation in TAFs compared to CFs. The aberrant DNA methylation landscape of TAFs had a global impact on gene expression and a selective impact on the TGF-β pathway. The latter included promoter hypermethylation-associated SMAD3 silencing, which was associated with hyperresponsiveness to exogenous TGF-β1 in terms of contractility and extracellular matrix deposition. In turn, activation of CFs with exogenous TGF-β1 partially mimicked the epigenetic alterations observed in TAFs, suggesting that TGF-β1 may be necessary but not sufficient to elicit such alterations. Moreover, integrated pathway-enrichment analyses of the DNA methylation alterations revealed that a fraction of TAFs may be bone marrow-derived fibrocytes. Finally, survival analyses using DNA methylation and gene expression datasets identified aberrant DNA methylation on the EDARADD promoter sequence as a prognostic factor in non-small cell lung cancer patients. Our findings shed light on the unique origin and molecular alterations underlying the aberrant phenotype of lung TAFs, and identify a stromal biomarker with potential clinical relevance. PMID:26449251

  16. Induction of chromosome aberrations in mammalian cells after heavy ion exposure

    NASA Astrophysics Data System (ADS)

    Ritter, S.; Kraft-Weyrather, W.; Scholz, M.; Kraft, G.

    The induction of chromosome aberrations by heavy charged particles was studied in V79 Chinese hamster cells over a wide range of energies (3-100 MeV/u) and LET (20-16000 keV/μm). For comparison, X-ray experiments were performed. Our data indicate quantitative and qualitative differences in the response of cells to particle and x-ray irradiation. For the same level of cell survival the amount of damaged cells which can be observed is smaller in heavy ion (11.4 MeV/u Ar) irradiated samples. The highest yield of damaged cells is found 8 to 12 hours after particle irradiation and 4 hours after x-irradiation. Differences in the amount of damaged cells are attributed to cell cycle perturbations which interfere with the expression of damage. After heavy ion exposure the amount of cells reaching mitosis (mitotic index) decreases drastically and not all damaged cells reach mitosis within 48 hours after exposure. A portion of cells die in interphase. Cell cycle delays induced by x-ray irradiation are less pronounced and all cells reach the first post-irradiation mitosis within 24 hours after irradiation. Additionally, the damage produced by charged particles seems to be more severe. The disintegration of chromosomes was only observed after high LET radiation: an indication of the high and local energy deposition in the particle track. Only cross sections for the induction of chromosome aberrations in mitotic cells were reported in this paper because of the problems arising from the drastic cell cycle perturbations. In this case, cells were irradiated in mitosis and assayed immediately.

  17. Aberrant epigenetic regulators control expansion of human CD34+ hematopoietic stem/progenitor cells

    PubMed Central

    Faridi, Farnaz; Ponnusamy, Kanagaraju; Quagliano-Lo Coco, Isabell; Chen-Wichmann, Linping; Grez, Manuel; Henschler, Reinhard; Wichmann, Christian

    2013-01-01

    Transcription is a tightly regulated process ensuring the proper expression of numerous genes regulating all aspects of cellular behavior. Transcription factors regulate multiple genes including other transcription factors that together control a highly complex gene network. The transcriptional machinery can be “hijacked” by oncogenic transcription factors, thereby leading to malignant cell transformation. Oncogenic transcription factors manipulate a variety of epigenetic control mechanisms to fulfill gene regulatory and cell transforming functions. These factors assemble epigenetic regulators at target gene promoter sequences, thereby disturbing physiological gene expression patterns. Retroviral vector technology and the availability of “healthy” human hematopoietic CD34+ progenitor cells enable the generation of pre-leukemic cell models for the analysis of aberrant human hematopoietic progenitor cell expansion mediated by leukemogenic transcription factors. This review summarizes recent findings regarding the mechanism by which leukemogenic gene products control human hematopoietic CD34+ progenitor cell expansion by disrupting the normal epigenetic program. PMID:24348510

  18. Mechanics of Cell Growth

    PubMed Central

    Ateshian, Gerard A.; Morrison, Barclay; Holmes, Jeffrey W.; Hung, Clark T.

    2012-01-01

    Cell growth describes an essential feature of biological tissues. This growth process may be modeled by using a set of relatively simple governing equations based on the axioms of mass and momentum balance, and using a continuum framework that describes cells and tissues as mixtures of a solid matrix, a solvent and multiple solutes. In this model the mechanics of cell growth is driven by osmotic effects, regulated by the cells’ active uptake of solutes and passive uptake of solvent. By accounting for the anisotropy of the cells’ cytoskeletal structures or extracellular matrix, as well as external constraints, a wide variety of growing shapes may be produced as illustrated in various examples. PMID:22904576

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

    PubMed Central

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

    2013-01-01

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

  20. Aberrant DNA methylation reprogramming during induced pluripotent stem cell generation is dependent on the choice of reprogramming factors.

    PubMed

    Planello, Aline C; Ji, Junfeng; Sharma, Vivek; Singhania, Rajat; Mbabaali, Faridah; Müller, Fabian; Alfaro, Javier A; Bock, Christoph; De Carvalho, Daniel D; Batada, Nizar N

    2014-01-01

    The conversion of somatic cells into pluripotent stem cells via overexpression of reprogramming factors involves epigenetic remodeling. DNA methylation at a significant proportion of CpG sites in induced pluripotent stem cells (iPSCs) differs from that of embryonic stem cells (ESCs). Whether different sets of reprogramming factors influence the type and extent of aberrant DNA methylation in iPSCs differently remains unknown. In order to help resolve this critical question, we generated human iPSCs from a common fibroblast cell source using either the Yamanaka factors (OCT4, SOX2, KLF4 and cMYC) or the Thomson factors (OCT4, SOX2, NANOG and LIN28), and determined their genome-wide DNA methylation profiles. In addition to shared DNA methylation aberrations present in all our iPSCs, we identified Yamanaka-iPSC (Y-iPSC)-specific and Thomson-iPSC (T-iPSC)-specific recurrent aberrations. Strikingly, not only were the genomic locations of the aberrations different but also their types: reprogramming with Yamanaka factors mainly resulted in failure to demethylate CpGs, whereas reprogramming with Thomson factors mainly resulted in failure to methylate CpGs. Differences in the level of transcripts encoding DNMT3b and TET3 between Y-iPSCs and T-iPSCs may contribute partially to the distinct types of aberrations. Finally, de novo aberrantly methylated genes in Y-iPSCs were enriched for NANOG targets that are also aberrantly methylated in some cancers. Our study thus reveals that the choice of reprogramming factors influences the amount, location, and class of DNA methylation aberrations in iPSCs. These findings may provide clues into how to produce human iPSCs with fewer DNA methylation abnormalities. PMID:25408883

  1. AMPK Promotes Aberrant PGC1β Expression To Support Human Colon Tumor Cell Survival

    PubMed Central

    Fisher, Kurt W.; Das, Binita; Kim, Hyun Seok; Clymer, Beth K.; Gehring, Drew; Smith, Deandra R.; Costanzo-Garvey, Diane L.; Fernandez, Mario R.; Brattain, Michael G.; Kelly, David L.; MacMillan, John

    2015-01-01

    A major goal of cancer research is the identification of tumor-specific vulnerabilities that can be exploited for the development of therapies that are selectively toxic to the tumor. We show here that the transcriptional coactivators peroxisome proliferator-activated receptor gamma coactivator 1β (PGC1β) and estrogen-related receptor α (ERRα) are aberrantly expressed in human colon cell lines and tumors. With kinase suppressor of Ras 1 (KSR1) depletion as a reference standard, we used functional signature ontology (FUSION) analysis to identify the γ1 subunit of AMP-activated protein kinase (AMPK) as an essential contributor to PGC1β expression and colon tumor cell survival. Subsequent analysis revealed that a subunit composition of AMPK (α2β2γ1) is preferred for colorectal cancer cell survival, at least in part, by stabilizing the tumor-specific expression of PGC1β. In contrast, PGC1β and ERRα are not detectable in nontransformed human colon epithelial cells, and depletion of the AMPKγ1 subunit has no effect on their viability. These data indicate that Ras oncogenesis relies on the aberrant activation of a PGC1β-dependent transcriptional pathway via a specific AMPK isoform. PMID:26351140

  2. [Number of aberrations per cell as a parameter of chromosome instability. 2. Comparative analysis of the factors of different nature].

    PubMed

    Kutsokon', N K; Lazarenko, L M; Bezrukov, V F; Rashydov, N M; Grodzyns'kyĭ, D M

    2004-01-01

    The average number of aberrations per aberrant cell was concluded to carry out information on chromosome instability peculiarities induced by different mutagens as it was shown in our previous work. The purpose of the current study was to present comparative analysis of intercellular distribution of number of aberrations and their theoretical approximations. Distribution of numbers of aberrations per cell in Allium cepa L. and Allium fistulosum L. root tip cells induced by different mutagenic factors (gamma-irradiation, thiotepa, formaldehyde and seed aging) have been studied. The results were approximated to theoretical Poisson, geometric and negative binomial distributions. The intercellular distribution of aberrations did not correspond to any of the used theoretical distributions when A. cepa seeds were gamma-irradiated. There was some, but not regular, accordance with theoretical distributions when chemical mutagens thiotepa in A. cepa and formaldehyde in A. fistulosum and seed aging in both species were evaluated. During seed aging frequency of aberrant cells increased more quickly in A. fistulosum in comparison with A. cepa. PMID:15098449

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

    NASA Technical Reports Server (NTRS)

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

    2003-01-01

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

  4. Cell Growth Enhancement

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Exogene Corporation uses advanced technologies to enhance production of bio-processed substances like proteins, antibiotics and amino acids. Among them are genetic modification and a genetic switch. They originated in research for Jet Propulsion Laboratory. Extensive experiments in cell growth through production of hemoglobin to improve oxygen supply to cells were performed. By improving efficiency of oxygen use by cells, major operational expenses can be reduced. Greater product yields result in decreased raw material costs and more efficient use of equipment. A broad range of applications is cited.

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

    NASA Technical Reports Server (NTRS)

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

    2016-01-01

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

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

    NASA Technical Reports Server (NTRS)

    Hada, Megumi; Cucinotta, Francis; Wu, Honglu

    2009-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    2014-01-01

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

  8. Mast cell-deficient Kit(W-sh) "Sash" mutant mice display aberrant myelopoiesis leading to the accumulation of splenocytes that act as myeloid-derived suppressor cells.

    PubMed

    Michel, Anastasija; Schüler, Andrea; Friedrich, Pamela; Döner, Fatma; Bopp, Tobias; Radsak, Markus; Hoffmann, Markus; Relle, Manfred; Distler, Ute; Kuharev, Jörg; Tenzer, Stefan; Feyerabend, Thorsten B; Rodewald, Hans-Reimer; Schild, Hansjörg; Schmitt, Edgar; Becker, Marc; Stassen, Michael

    2013-06-01

    Mast cell-deficient Kit(W-sh) "sash" mice are widely used to investigate mast cell functions. However, mutations of c-Kit also affect additional cells of hematopoietic and nonimmune origin. In this study, we demonstrate that Kit(W-sh) causes aberrant extramedullary myelopoiesis characterized by the expansion of immature lineage-negative cells, common myeloid progenitors, and granulocyte/macrophage progenitors in the spleen. A consistent feature shared by these cell types is the reduced expression of c-Kit. Populations expressing intermediate and high levels of Ly6G, a component of the myeloid differentiation Ag Gr-1, are also highly expanded in the spleen of sash mice. These cells are able to suppress T cell responses in vitro and phenotypically and functionally resemble myeloid-derived suppressor cells (MDSC). MDSC typically accumulate in tumor-bearing hosts and are able to dampen immune responses. Consequently, transfer of MDSC from naive sash mice into line 1 alveolar cell carcinoma tumor-bearing wild-type littermates leads to enhanced tumor progression. However, although it can also be observed in sash mice, accelerated growth of transplanted line 1 alveolar cell carcinoma tumors is a mast cell-independent phenomenon. Thus, the Kit(W-sh) mutation broadly affects key steps in myelopoiesis that may have an impact on mast cell research. PMID:23636054

  9. Aberrant protein phosphorylation in Alzheimer disease brain disturbs pro-survival and cell death pathways.

    PubMed

    Perluigi, M; Barone, E; Di Domenico, F; Butterfield, D A

    2016-10-01

    Protein phosphorylation of serine, threonine, and tyrosine residues is one of the most prevalent post-translational modifications fundamental in mediating diverse cellular functions in living cells. Aberrant protein phosphorylation is currently recognized as a critical step in the pathogenesis and progression of Alzheimer disease (AD). Changes in the pattern of protein phosphorylation of different brain regions are suggested to promote AD transition from a presymptomatic to a symptomatic state in response to accumulating amyloid β-peptide (Aβ). Several experimental approaches have been utilized to profile alteration of protein phosphorylation in the brain, including proteomics. Among central pathways regulated by kinases/phosphatases those involved in the activation/inhibition of both pro survival and cell death pathways play a central role in AD pathology. We discuss in detail how aberrant phosphorylation could contribute to dysregulate p53 activity and insulin-mediated signaling. Taken together these results highlight that targeted therapeutic intervention, which can restore phosphorylation homeostasis, either acting on kinases and phosphatases, conceivably may prove to be beneficial to prevent or slow the development and progression of AD.

  10. Aberrant protein phosphorylation in Alzheimer disease brain disturbs pro-survival and cell death pathways.

    PubMed

    Perluigi, M; Barone, E; Di Domenico, F; Butterfield, D A

    2016-10-01

    Protein phosphorylation of serine, threonine, and tyrosine residues is one of the most prevalent post-translational modifications fundamental in mediating diverse cellular functions in living cells. Aberrant protein phosphorylation is currently recognized as a critical step in the pathogenesis and progression of Alzheimer disease (AD). Changes in the pattern of protein phosphorylation of different brain regions are suggested to promote AD transition from a presymptomatic to a symptomatic state in response to accumulating amyloid β-peptide (Aβ). Several experimental approaches have been utilized to profile alteration of protein phosphorylation in the brain, including proteomics. Among central pathways regulated by kinases/phosphatases those involved in the activation/inhibition of both pro survival and cell death pathways play a central role in AD pathology. We discuss in detail how aberrant phosphorylation could contribute to dysregulate p53 activity and insulin-mediated signaling. Taken together these results highlight that targeted therapeutic intervention, which can restore phosphorylation homeostasis, either acting on kinases and phosphatases, conceivably may prove to be beneficial to prevent or slow the development and progression of AD. PMID:27425034

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

    NASA Technical Reports Server (NTRS)

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

    1998-01-01

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

  12. Induction of aberrant trimethylation of histone H3 lysine 27 by inflammation in mouse colonic epithelial cells.

    PubMed

    Takeshima, Hideyuki; Ikegami, Daigo; Wakabayashi, Mika; Niwa, Tohru; Kim, Young-Joon; Ushijima, Toshikazu

    2012-12-01

    A field for cancerization (field defect), where genetic and epigenetic alterations are accumulated in normal-appearing tissues, is involved in human carcinogenesis, especially cancers associated with chronic inflammation. Although aberrant DNA methylation is involved in the field defect and induced by chronic inflammation, it is still unclear for trimethylation of histone H3 lysine 27 (H3K27me3), which is involved in gene repression independent of DNA methylation and functions as a pre-mark for aberrant DNA methylation. In this study, using a mouse colitis model induced by dextran sulfate sodium (DSS), we aimed to clarify whether aberrant H3K27me3 is induced by inflammation and involved in a field defect. ChIP-on-chip analysis of colonic epithelial cells revealed that H3K27me3 levels were increased or decreased for 266 genomic regions by aging, and more extensively (23 increased and 3574 decreased regions) by colitis. Such increase or decrease of H3K27me3 was induced as early as 2 weeks after the initiation of DSS treatment, and persisted at least for 16 weeks even after the inflammation disappeared. Some of the aberrant H3K27me3 in colonic epithelial cells was carried over into colon tumors. Furthermore, H3K27me3 acquired at Dapk1 by colitis was followed by increased DNA methylation, supporting its function as a pre-mark for aberrant DNA methylation. These results demonstrated that aberrant H3K27me3 can be induced by exposure to a specific environment, such as colitis, and suggested that aberrant histone modification, in addition to aberrant DNA methylation, is involved in the formation of a field defect.

  13. Signatures of post-zygotic structural genetic aberrations in the cells of histologically normal breast tissue that can predispose to sporadic breast cancer

    PubMed Central

    Forsberg, Lars A.; Rasi, Chiara; Pekar, Gyula; Davies, Hanna; Piotrowski, Arkadiusz; Absher, Devin; Razzaghian, Hamid Reza; Ambicka, Aleksandra; Halaszka, Krzysztof; Przewoźnik, Marcin; Kruczak, Anna; Mandava, Geeta; Pasupulati, Saichand; Hacker, Julia; Prakash, K. Reddy; Dasari, Ravi Chandra; Lau, Joey; Penagos-Tafurt, Nelly; Olofsson, Helena M.; Hallberg, Gunilla; Skotnicki, Piotr; Mituś, Jerzy; Skokowski, Jaroslaw; Jankowski, Michal; Śrutek, Ewa; Zegarski, Wojciech; Tiensuu Janson, Eva; Ryś, Janusz; Tot, Tibor; Dumanski, Jan P.

    2015-01-01

    Sporadic breast cancer (SBC) is a common disease without robust means of early risk prediction in the population. We studied 282 females with SBC, focusing on copy number aberrations in cancer-free breast tissue (uninvolved margin, UM) outside the primary tumor (PT). In total, 1162 UMs (1–14 per breast) were studied. Comparative analysis between UM(s), PT(s), and blood/skin from the same patient as a control is the core of the study design. We identified 108 patients with at least one aberrant UM, representing 38.3% of cases. Gains in gene copy number were the principal type of mutations in microscopically normal breast cells, suggesting that oncogenic activation of genes via increased gene copy number is a predominant mechanism for initiation of SBC pathogenesis. The gain of ERBB2, with overexpression of HER2 protein, was the most common aberration in normal cells. Five additional growth factor receptor genes (EGFR, FGFR1, IGF1R, LIFR, and NGFR) also showed recurrent gains, and these were occasionally present in combination with the gain of ERBB2. All the aberrations found in the normal breast cells were previously described in cancer literature, suggesting their causative, driving role in pathogenesis of SBC. We demonstrate that analysis of normal cells from cancer patients leads to identification of signatures that may increase risk of SBC and our results could influence the choice of surgical intervention to remove all predisposing cells. Early detection of copy number gains suggesting a predisposition toward cancer development, long before detectable tumors are formed, is a key to the anticipated shift into a preventive paradigm of personalized medicine for breast cancer. PMID:26430163

  14. Signatures of post-zygotic structural genetic aberrations in the cells of histologically normal breast tissue that can predispose to sporadic breast cancer.

    PubMed

    Forsberg, Lars A; Rasi, Chiara; Pekar, Gyula; Davies, Hanna; Piotrowski, Arkadiusz; Absher, Devin; Razzaghian, Hamid Reza; Ambicka, Aleksandra; Halaszka, Krzysztof; Przewoźnik, Marcin; Kruczak, Anna; Mandava, Geeta; Pasupulati, Saichand; Hacker, Julia; Prakash, K Reddy; Dasari, Ravi Chandra; Lau, Joey; Penagos-Tafurt, Nelly; Olofsson, Helena M; Hallberg, Gunilla; Skotnicki, Piotr; Mituś, Jerzy; Skokowski, Jaroslaw; Jankowski, Michal; Śrutek, Ewa; Zegarski, Wojciech; Tiensuu Janson, Eva; Ryś, Janusz; Tot, Tibor; Dumanski, Jan P

    2015-10-01

    Sporadic breast cancer (SBC) is a common disease without robust means of early risk prediction in the population. We studied 282 females with SBC, focusing on copy number aberrations in cancer-free breast tissue (uninvolved margin, UM) outside the primary tumor (PT). In total, 1162 UMs (1-14 per breast) were studied. Comparative analysis between UM(s), PT(s), and blood/skin from the same patient as a control is the core of the study design. We identified 108 patients with at least one aberrant UM, representing 38.3% of cases. Gains in gene copy number were the principal type of mutations in microscopically normal breast cells, suggesting that oncogenic activation of genes via increased gene copy number is a predominant mechanism for initiation of SBC pathogenesis. The gain of ERBB2, with overexpression of HER2 protein, was the most common aberration in normal cells. Five additional growth factor receptor genes (EGFR, FGFR1, IGF1R, LIFR, and NGFR) also showed recurrent gains, and these were occasionally present in combination with the gain of ERBB2. All the aberrations found in the normal breast cells were previously described in cancer literature, suggesting their causative, driving role in pathogenesis of SBC. We demonstrate that analysis of normal cells from cancer patients leads to identification of signatures that may increase risk of SBC and our results could influence the choice of surgical intervention to remove all predisposing cells. Early detection of copy number gains suggesting a predisposition toward cancer development, long before detectable tumors are formed, is a key to the anticipated shift into a preventive paradigm of personalized medicine for breast cancer.

  15. Molecular aberrations of the G1-S checkpoint in myxoid and round cell liposarcoma.

    PubMed Central

    Dei Tos, A. P.; Piccinin, S.; Doglioni, C.; Vukosavljevic, T.; Mentzel, T.; Boiocchi, M.; Fletcher, C. D.

    1997-01-01

    Myxoid and round cell liposarcoma represents a morphological spectrum in which tumor progression from low-grade myxoid to high-grade round cell areas is frequently observed. A distinctive t(12;16)(q13;p11) reciprocal translocation rearranges the CHOP gene localized to 12q13 in most cases. Data concerning the occurrence of cell cycle aberrations in this subset of mesenchymal malignancies are very limited. Therefore, we analyzed a histologically homogeneous series of 21 cases of myxoid and round cell liposarcoma. The p53 pathway was studied by investigating the TP53 gene and protein, mdm2 protein, and p21Waf1 protein. The Rb-cyclin D pathway was analyzed by studying the pRb protein, the p16MTS1 gene, cyclin D1, cyclin D3, p27Kip1, cdk4, and cdk6 proteins. In contrast with the rare involvement of the TP53 gene in well differentiated liposarcoma, aberrations of the TP53 gene were observed in approximately 30% of cases of myxoid and round cell liposarcoma. Notably, mdm2 overexpression was seen in 56% of cases and correlated with histological grade, therefore indicating a possible role in tumor progression. Abnormalities involving the Rb-cyclin D pathway were observed in more than 90% of cases. pRb loss was present in one-third of cases and, at variance with that observed in other subsets of sarcoma, overexpression of cyclin Ds represented a rare event. Interestingly, upregulation of either cdk4 or cdk6 was demonstrated in 85% of cases. Images Figure 1 Figure 2 Figure 3 PMID:9403703

  16. Cytogenetic investigation of chromosomal aberrations in cells treated with plantamajoside from Plantago asiatica.

    PubMed

    Koo, Yun-Chang; Jung, Sung-Hoon; Yang, Ji-Hee; Ryu, Yung-Sun; Kim, Eun-Jin; Lee, Kwang-Won

    2009-10-01

    Plantago asiatica is a member of the Plantaginaceae family, and is widely distributed in East Asia. In our previous work, a single active compound, plantamajoside was isolated and confirmed to have glycation inhibitory activity, and did not possess toxicity during a 90 day repeated oral toxicity test in rats. In the present study, a chromosomal aberration test was performed to investigate the genotoxicity of plantamajoside. From the results of the cytotoxicity test, plantamajoside proved to be less toxic when it was treated combined with S9 cell fractions. However, there was a significant increase in structural aberrations during the short-term treatment of plantamajoside at its highest dose (5000 microg/mL) even when combined with S9. This seems to have been a natural phenomenon due to the very high dose of plantamajoside that was used. However, to confirm the safety of plantamajoside for its potential use as a phytochemical agent in health products, additional mutagenicity tests are necessary. PMID:19288521

  17. Interpreting Chromosome Aberration Spectra

    NASA Technical Reports Server (NTRS)

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

    2007-01-01

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

  18. Chromosome aberrations, spontaneous SCE, and growth kinetics in PHA-stimulated lymphocytes of five cases with Sézary syndrome.

    PubMed

    Limon, J; Nedoszytko, B; Brozek, I; Hellmann, A; Zajaczek, S; Lubiński, J; Mrózek, K

    1995-08-01

    Cytogenetic studies of five patients with Sézary syndrome (SS) revealed clonal chromosome aberrations in all cases. In one patient, a del(8)(p21) was the sole abnormality, whereas the remaining cases had karyotypes with multiple chromosome changes. In three SS cases with hypodiploid chromosome numbers, structural rearrangements affecting regions 10q22-24 and 12p11-13, and aberrations leading to loss of material from 17p were found concurrently. Bands 14q11 and 14q32 were involved in structural rearrangements in one case each. Our results and review of 51 published previously SS cases that were analyzed with banding techniques indicate that the chromosomes most frequently involved in structural changes were chromosomes 1 and 2 (in 43% of cases), 6 (in 38%), 17 (in 34%), 14 (in 27%), 11 (in 25%), 13 (in 21%), and 9 (in 20%). In particular, the breakpoints tended to aggregate at 1p11, 1p36, 2p11-24, 6q, 9q, 11q, 13q11-14, 14q11, 14q32, and in the pericentric region of chromosome 17. The most common numerical change was loss of chromosome 10, detected in 32% of SS cases. In our studies of three SS cases, sister chromatid exchange frequencies were significantly higher in comparison to the normal control. Cell cycle kinetics analysis revealed that the cell cycle time in the malignant cells was significantly longer than in lymphocytes of normal individuals.

  19. Ability of fourteen chemical agents used in dental practice to induce chromosome aberrations in Syrian hamster embryo cells.

    PubMed

    Hikiba, Hirohito; Watanabe, Eiko; Barrett, J Carl; Tsutsui, Takeki

    2005-01-01

    To assess the genotoxicity of 14 chemical agents used in dental practice, the ability of these agents to induce chromosome aberrations was examined using Syrian hamster embryo (SHE) cells. Statistically significant increases in the frequencies of chromosome aberrations were induced in SHE cells treated with 7 of 10 chemical agents used as endodontic medicaments, that is, carbol camphor, m-cresol, eugenol, guaiacol, zinc oxide, hydrogen peroxide, and formaldehyde. The other 3 chemical agents, that is, thymol, glutaraldehyde, and iodoform, did not increase the levels of chromosome aberrations. Of the 4 chemical agents that are used as an antiseptic on the oral mucosa, chromosome aberrations were induced by iodine, but not by the other 3 antiseptics, benzalkonium chloride, benzethonium chloride, and chlorhexidine. Among the 6 chemical agents exhibiting a negative response in the assay, only thymol induced chromosome aberrations in the presence of exogenous metabolic activation. Our results indicate that chemical agents having a positive response in the present study are potentially genotoxic to mammalian cells and need to be studied further in detail. PMID:15665446

  20. Aberrant cell cycle regulation in rat liver cells induced by post-initiation treatment with hepatocarcinogens/hepatocarcinogenic tumor promoters.

    PubMed

    Kimura, Masayuki; Mizukami, Sayaka; Watanabe, Yousuke; Onda, Nobuhiko; Yoshida, Toshinori; Shibutani, Makoto

    2016-08-01

    The present study aimed to determine the onset time of hepatocarcinogen/hepatocarcinogenic tumor promoter-specific cell proliferation, apoptosis and aberrant cell cycle regulation after post-initiation treatment. Six-week-old rats were treated with the genotoxic hepatocarcinogen, carbadox (CRB), the marginally hepatocarcinogenic leucomalachite green (LMG), the tumor promoter, β-naphthoflavone (BNF) or the non-carcinogenic hepatotoxicant, acetaminophen, for 2, 4 or 6 weeks during the post-initiation phase using a medium-term liver bioassay. Cell proliferation activity, expression of G2 to M phase- and spindle checkpoint-related molecules, and apoptosis were immunohistochemically analyzed at week 2 and 4, and tumor promotion activity was assessed at week 6. At week 2, hepatocarcinogen/tumor promoter-specific aberrant cell cycle regulation was not observed. At week 4, BNF and LMG increased cell proliferation together with hepatotoxicity, while CRB did not. Additionally, BNF and CRB reduced the number of cells expressing phosphorylated-histone H3 in both ubiquitin D (UBD)(+) cells and Ki-67(+) proliferating cells, suggesting development of spindle checkpoint dysfunction, regardless of cell proliferation activity. At week 6, examined hepatocarcinogens/tumor promoters increased preneoplastic hepatic foci expressing glutathione S-transferase placental form. These results suggest that some hepatocarcinogens/tumor promoters increase their toxicity after post-initiation treatment, causing regenerative cell proliferation. In contrast, some genotoxic hepatocarcinogens may disrupt the spindle checkpoint without facilitating cell proliferation at the early stage of tumor promotion. This suggests that facilitation of cell proliferation and disruption of spindle checkpoint function are induced by different mechanisms during hepatocarcinogenesis. Four weeks of post-initiation treatment may be sufficient to induce hepatocarcinogen/tumor promoter-specific cellular responses. PMID

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

    USGS Publications Warehouse

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

    2003-01-01

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

  2. Three-dimensional locations of gold-labeled proteins in a whole mount eukaryotic cell obtained with 3 nm precision using aberration-corrected scanning transmission electron microscopy

    PubMed Central

    Dukes, Madeline J.; Ramachandra, Ranjan; Baudoin, Jean-Pierre; Jerome, W. Gray; de Jonge, Niels

    2011-01-01

    Three-dimensional (3D) maps of proteins within the context of whole cells are important for investigating cellular function. However, 3D reconstructions of whole cells are challenging to obtain using conventional transmission electron microscopy (TEM). We describe a methodology to determine the 3D locations of proteins labeled with gold nanoparticles on whole eukaryotic cells. The epidermal growth factor receptors on COS7 cells were labeled with gold nanoparticles, and critical-point dried whole-mount cell samples were prepared. 3D focal series were obtained with aberration-corrected scanning transmission electron microscopy (STEM), without tilting the specimen. The axial resolution was improved with deconvolution. The vertical locations of the nanoparticles in a whole-mount cell were determined with a precision of 3 nm. From the analysis of the variation of the axial positions of the labels we concluded that the cellular surface was ruffled. To achieve sufficient stability of the sample under the electron beam irradiation during the recording of the focal series, the sample was carbon coated. A quantitative method was developed to analyze the stability of the ultrastructure after electron beam irradiation using TEM. The results of this study demonstrate the feasibility of using aberration-corrected STEM to study the 3D nanoparticle distribution in whole cells. PMID:21440635

  3. Three-dimensional locations of gold-labeled proteins in a whole mount eukaryotic cell obtained with 3nm precision using aberration-corrected scanning transmission electron microscopy.

    PubMed

    Dukes, Madeline J; Ramachandra, Ranjan; Baudoin, Jean-Pierre; Gray Jerome, W; de Jonge, Niels

    2011-06-01

    Three-dimensional (3D) maps of proteins within the context of whole cells are important for investigating cellular function. However, 3D reconstructions of whole cells are challenging to obtain using conventional transmission electron microscopy (TEM). We describe a methodology to determine the 3D locations of proteins labeled with gold nanoparticles on whole eukaryotic cells. The epidermal growth factor receptors on COS7 cells were labeled with gold nanoparticles, and critical-point dried whole-mount cell samples were prepared. 3D focal series were obtained with aberration-corrected scanning transmission electron microscopy (STEM), without tilting the specimen. The axial resolution was improved with deconvolution. The vertical locations of the nanoparticles in a whole-mount cell were determined with a precision of 3nm. From the analysis of the variation of the axial positions of the labels we concluded that the cellular surface was ruffled. To achieve sufficient stability of the sample under electron beam irradiation during the recording of the focal series, the sample was carbon coated. A quantitative method was developed to analyze the stability of the ultrastructure after electron beam irradiation using TEM. The results of this study demonstrate the feasibility of using aberration-corrected STEM to study the 3D nanoparticle distribution in whole cells.

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

    NASA Technical Reports Server (NTRS)

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

    2014-01-01

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

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

    PubMed

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

    2014-10-01

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

  6. Malignant Peripheral Nerve Sheath Tumor Invasion Requires Aberrantly Expressed Epidermal Growth Factor (EGF) Receptors and is Variably Enhanced by Multiple EGF Family Ligands

    PubMed Central

    Byer, Stephanie J.; Brossier, Nicole M.; Peavler, Lafe T.; Eckert, Jenell M.; Watkins, Stacey; Roth, Kevin A.; Carroll, Steven L.

    2013-01-01

    Aberrant epidermal growth factor receptor (EGFR) expression promotes the pathogenesis of malignant peripheral nerve sheath tumors (MPNSTs), the most common malignancy associated with neurofibromatosis type 1, but the mechanisms by which EGFR expression promotes MPNST pathogenesis are poorly understood. We hypothesized that inappropriately expressed EGFRs promote MPNST invasion and found that these kinases are concentrated in MPNST invadopodia in vitro. EGFR knockdown inhibited the migration of unstimulated MPNST cells in vitro and exogenous EGF further enhanced MPNST migration in a substrate-specific manner, promoting migration on laminin and, to a lesser extent, collagen. Thus, in this setting, EGF acts as a chemotactic factor. We also found that the 7 known EGFR ligands (EGF, betacellulin, epiregulin, heparin-binding EGF, transforming growth factor α [TGFα], amphiregulin, and epigen) variably enhanced MPNST migration in a concentration-dependent manner, with TGFα being particularly potent. With the exception of epigen, these factors similarly promoted the migration of non-neoplastic Schwann cells. Although transcripts encoding all 7 EGFR ligands were detected in human MPNST cells and tumor tissues, only TGFα was consistently overexpressed and was found to colocalize with EGFR in situ. These data indicate that constitutive EGFR activation, potentially driven by autocrine or paracrine TGFα signaling, promotes the aggressive invasive behavior characteristic of MPNSTs. PMID:23399900

  7. NrasG12D/+ promotes leukemogenesis by aberrantly regulating hematopoietic stem cell functions

    PubMed Central

    Wang, Jinyong; Kong, Guangyao; Liu, Yangang; Du, Juan; Chang, Yuan-I; Tey, Sin Ruow; Zhang, Xinmin; Ranheim, Erik A.; Saba-El-Leil, Marc K.; Meloche, Sylvain; Damnernsawad, Alisa; Zhang, Jingfang; Zhang, Jing

    2013-01-01

    Oncogenic NRAS mutations are frequently identified in human myeloid leukemias. In mice, expression of endogenous oncogenic Nras (NrasG12D/+) in hematopoietic cells leads to expansion of myeloid progenitors, increased long-term reconstitution of bone marrow cells, and a chronic myeloproliferative neoplasm (MPN). However, acute expression of NrasG12D/+ in a pure C57BL/6 background does not induce hyperactivated granulocyte macrophage colony-stimulating factor signaling or increased proliferation in myeloid progenitors. It is thus unclear how NrasG12D/+ signaling promotes leukemogenesis. Here, we show that hematopoietic stem cells (HSCs) expressing NrasG12D/+ serve as MPN-initiating cells. They undergo moderate hyperproliferation with increased self-renewal. The aberrant NrasG12D/+ HSC function is associated with hyperactivation of ERK1/2 in HSCs. Conversely, downregulation of MEK/ERK by pharmacologic and genetic approaches attenuates the cycling of NrasG12D/+ HSCs and prevents the expansion of NrasG12D/+ HSCs and myeloid progenitors. Our data delineate critical mechanisms of oncogenic Nras signaling in HSC function and leukemogenesis. PMID:23687087

  8. Aberrant Neural Stem Cell Proliferation and Increased Adult Neurogenesis in Mice Lacking Chromatin Protein HMGB2

    PubMed Central

    Reddy, Avanish S.; Maletic-Savatic, Mirjana; Aguirre, Adan; Tsirka, Stella E.

    2013-01-01

    Neural stem and progenitor cells (NSCs/NPCs) are distinct groups of cells found in the mammalian central nervous system (CNS). Previously we determined that members of the High Mobility Group (HMG) B family of chromatin structural proteins modulate NSC proliferation and self-renewal. Among them HMGB2 was found to be dynamically expressed in proliferating and differentiating NSCs, suggesting that it may regulate NSC maintenance. We report now that Hmgb2−/− mice exhibit SVZ hyperproliferation, increased numbers of SVZ NSCs, and a trend towards aberrant increases in newly born neurons in the olfactory bulb (OB) granule cell layer. Increases in the levels of the transcription factor p21 and the Neural cell adhesion molecule (NCAM), along with down-regulation of the transcription/pluripotency factor Oct4 in the Hmgb2−/− SVZ point to a possible pathway for this increased proliferation/differentiation. Our findings suggest that HMGB2 functions as a modulator of neurogenesis in young adult mice through regulation of NSC proliferation, and identify a potential target via which CNS repair could be amplified following trauma or disease-based neuronal degeneration. PMID:24391977

  9. Aberrant caspase-activated DNase (CAD) transcripts in human hepatoma cells.

    PubMed

    Hsieh, S Y; Liaw, S F; Lee, S N; Hsieh, P S; Lin, K H; Chu, C M; Liaw, Y F

    2003-01-27

    The gene of caspase-activated DNase (CAD), the key enzyme for nucleosome cleavage during apoptosis, is mapped at chromosome 1p36, a region usually associated with hemizygous deletions in human cancers, particularly in hepatoma (HCC). It is tempting to speculate that CAD plays a tumour-suppressive role in hepatocarcinogenesis. To address this, we examined the CAD transcripts in six human HCC cell lines, one liver tissue from a non-HCC subject, and peripheral blood leukocytes (PBL) from three healthy individuals. Alternatively spliced CAD transcripts with fusion of exon 1 to exon 7 were isolated in most of the examined samples including HCC cells and normal controls. However, relatively abundant alternatively spliced CAD transcripts with fusion of exon 2 to exon 6 or 7, in which the corresponding domain directing CAD interaction with ICAD was preserved, were found only in poorly differentiated Mahlavu and SK-Hep1 cells. Interestingly, an abnormal CAD transcript with its exon 3 replaced by a truncated transposable Alu repeat was isolated in Hep3B cells, indicative of the implication of an Alu-mediated genomic mutation. Moreover, mis-sense mutations in the CAD genes were identified in all six HCC cell lines. Upon UV-induced apoptosis, DNA fragmentation efficiency was found to be intact, partially reduced and remarkably reduced in Huh7 and J328, Hep3B and HepG2, and Mahlavu cells, respectively. That mutations and aberrantly spliced transcripts for the CAD gene are frequently present in human HCC cells, especially in poorly differentiated HCC cells, suggests a significant role of CAD in human hepatocarcinogenesis.

  10. Aberrant Cytoplasm Localization and Protein Stability of SIRT1 is Regulated by PI3K/IGF-1R Signaling in Human Cancer Cells

    PubMed Central

    Byles, Vanessa; Chmilewski, Laura K.; Wang, Joyce; Zhu, Lijia; Forman, Lora W.; Faller, Douglas V.; Dai, Yan

    2010-01-01

    SIRT1, an NAD-dependent histone/protein deacetylase, has classically been thought of as a nuclear protein. In this study, we demonstrate that SIRT1 is mainly localized in the nucleus of normal cells, but is predominantly localized in the cytoplasm of the cancer / transformed cells we tested. We found this predominant cytoplasmic localization of SIRT1 is regulated by elevated mitotic activity and PI3K/IGF-1R signaling in cancer cells. We show that aberrant cytoplasmic localization of SIRT1 is due to increased protein stability and is regulated by PI3K/IGF-1R signaling. In addition, we determined that SIRT1 is required for PI3K-mediated cancer cell growth. Our study represents the first identification that aberrant cytoplasm localization is one of the specific alternations to SIRT1 that occur in cancer cells, and PI3K/IGF-1R signaling plays an important role in the regulation of cytoplasmic SIRT1 stability. Our findings suggest that the over-expressed cytoplasmic SIRT1 in cancer cells may greatly contribute to its cancer-specific function by working downstream of the PI3K/IGF-1R signaling pathway. PMID:20941378

  11. Estimating the number of hematopoietic or lymphoid stem cells giving rise to clonal chromosome aberrations in blood T lymphocytes.

    PubMed

    Nakano, M; Kodama, Y; Ohtaki, K; Itoh, M; Awa, A A; Cologne, J; Kusunoki, Y; Nakamura, N

    2004-03-01

    Quantifying the proliferative capacity of long-term hematopoietic stem cells in humans is important for bone marrow transplantation and gene therapy. Obtaining appropriate data is difficult, however, because the experimental tools are limited. We hypothesized that tracking clonal descendants originating from hematopoietic stem cells would be possible if we used clonal chromosome aberrations as unique tags of individual hematopoietic stem cells in vivo. Using FISH, we screened 500 blood T lymphocytes from each of 513 atomic bomb survivors and detected 96 clones composed of at least three cells with identical aberrations. The number of clones was inversely related to their population size, which we interpreted to mean that the progenitor cells were heterogeneous in the number of progeny that they could produce. The absolute number of progenitor cells contributing to the formation of the observed clones was estimated as about two in an unexposed individual. Further, scrutiny of ten clones revealed that lymphocyte clones could originate roughly equally from hematopoietic stem cells or from mature T lymphocytes, thereby suggesting that the estimated two progenitor cells are shared as one hematopoietic stem cell and one mature T cell. Our model predicts that one out of ten people bears a non- aberrant clone comprising >10% of the total lymphocytes, which indicates that clonal expansions are common and probably are not health-threatening. PMID:14982487

  12. Gaucher Disease-Induced Pluripotent Stem Cells Display Decreased Erythroid Potential and Aberrant Myelopoiesis

    PubMed Central

    Sgambato, Judi A.; Park, Tea Soon; Miller, Diana; Panicker, Leelamma M.; Sidransky, Ellen; Lun, Yu; Awad, Ola; Bentzen, Søren M.; Zambidis, Elias T.

    2015-01-01

    Gaucher disease (GD) is the most common lysosomal storage disease resulting from mutations in the lysosomal enzyme glucocerebrosidase (GCase). The hematopoietic abnormalities in GD include the presence of characteristic Gaucher macrophages that infiltrate patient tissues and cytopenias. At present, it is not clear whether these cytopenias are secondary to the pathological activity of Gaucher cells or a direct effect of GCase deficiency on hematopoietic development. To address this question, we differentiated induced pluripotent stem cells (iPSCs) derived from patients with types 1, 2, and 3 GD to CD34+/CD45+/CD43+/CD143+ hematopoietic progenitor cells (HPCs) and examined their developmental potential. The formation of GD-HPCs was unaffected. However, these progenitors demonstrated a skewed lineage commitment, with increased myeloid differentiation and decreased erythroid differentiation and maturation. Interestingly, myeloid colony-formation assays revealed that GD-HPCs, but not control-HPCs, gave rise to adherent, macrophage-like cells, another indication of abnormal myelopoiesis. The extent of these hematologic abnormalities correlated with the severity of the GCase mutations. All the phenotypic abnormalities of GD-HPCs observed were reversed by incubation with recombinant GCase, indicating that these developmental defects were caused by the mutated GCase. Our results show that GCase deficiency directly impairs hematopoietic development. Additionally, our results suggest that aberrant myelopoiesis might contribute to the pathological properties of Gaucher macrophages, which are central to GD manifestations. The hematopoietic developmental defects we observed reflect hematologic abnormalities in patients with GD, demonstrating the utility of GD-iPSCs for modeling this disease. Significance This study showed that hematopoietic progenitors from patients with Gaucher disease (GD) have intrinsic developmental abnormalities that reflect characteristic clinical

  13. Genome aberrations in canine mammary carcinomas and their detection in cell-free plasma DNA.

    PubMed

    Beck, Julia; Hennecke, Silvia; Bornemann-Kolatzki, Kirsten; Urnovitz, Howard B; Neumann, Stephan; Ströbel, Philipp; Kaup, Franz-Josef; Brenig, Bertram; Schütz, Ekkehard

    2013-01-01

    Mammary tumors are the most frequent cancers in female dogs exhibiting a variety of histopathological differences. There is lack of knowledge about the genomes of these common dog tumors. Five tumors of three different histological subtypes were evaluated. Massive parallel sequencing (MPS) was performed in comparison to the respective somatic genome of each animal. Copy number and structural aberrations were validated using droplet digital PCR (ddPCR). Using mate-pair sequencing chromosomal aneuploidies were found in two tumors, frequent smaller deletions were found in one, inter-chromosomal fusions in one other, whereas one tumor was almost normal. These aberrations affect several known cancer associated genes such as cMYC, and KIT. One common deletion of the proximal end of CFA27, harboring the tumor suppressor gene PFDN5 was detected in four tumors. Using ddPCR, this deletion was validated and detected in 50% of tumors (N = 20). Breakpoint specific dPCRs were established for four tumors and tumor specific cell-free DNA (cfDNA) was detected in the plasma. In one animal tumor-specific cfDNA was found >1 year after surgery, attributable to a lung metastasis. Paired-end sequencing proved that copy-number imbalances of the tumor are reflected by the cfDNA. This report on chromosomal instability of canine mammary cancers reveals similarities to human breast cancers as well as special canine alterations. This animal model provides a framework for using MPS for screening for individual cancer biomarkers with cost effective confirmation and monitoring using ddPCR. The possibility exists that ddPCR can be expanded to screening for common cancer related variants. PMID:24098698

  14. HABP1/p32/gC1qR induces aberrant growth and morphology in Schizosaccharomyces pombe through its N-terminal {alpha} helix

    SciTech Connect

    Mallick, Jaideep; Datta, Kasturi . E-mail: kdatta@mail.jnu.ac.in

    2005-10-01

    Hyaluronan binding protein (HABP1), located on human chromosome 17p13.3, was identified and characterized as being involved in cellular signaling from our laboratory. Here, we demonstrate that HABP1 expression in Schizosaccharomyces pombe induces growth inhibition, morphological abnormalities like elongation, multinucleation and aberrant cell septum formation in several strains of S. pombe, implicating its role in cell cycle progression and cytokinesis. This argument is further strengthened by an observed delay in the maximal expression of cell cycle regulatory proteins like CDC 2 and CDC 25 coupled to the direct interaction of HABP1 with CDC 25. In order to pinpoint the interacting domain of HABP1, its N- and C-terminal truncated variants ({delta}N.HABP1 and {delta}C.HABP1, respectively) were utilized which revealed that while expression of the former did not alter the phenotype, the latter generated morphological changes similar to those imparted upon HABP1 expression. It was also noted that along with HABP1, {delta}C.HABP1 too directly interacts with CDC 25 while {delta}N.HABP1 does not. Taken together, these data suggest that HABP1 induces morphological changes and modulates the cell cycle by interacting with proteins like CDC 25 through its N-terminal {alpha}-helix.

  15. Aberrant cell proliferation by enhanced mitochondrial biogenesis via mtTFA in arsenical skin cancers.

    PubMed

    Lee, Chih-Hung; Wu, Shi-Bei; Hong, Chien-Hui; Liao, Wei-Ting; Wu, Ching-Ying; Chen, Gwo-Shing; Wei, Yau-Huei; Yu, Hsin-Su

    2011-05-01

    Arsenic-induced Bowen's disease (As-BD), a cutaneous carcinoma in situ, is thought to arise from gene mutation and uncontrolled proliferation. However, how mitochondria regulate the arsenic-induced cell proliferation remains unclear. The aim of this study was to clarify whether arsenic interfered with mitochondrial biogenesis and function, leading to aberrant cell proliferation in As-BD. Skin biopsy samples from patients with As-BD and controls were stained for cytochrome c oxidase (Complex IV), measured for mitochondrial DNA (mtDNA) copy number and the expression levels of mitochondrial biogenesis-related genes, including peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), nuclear respiratory factor 1 (NRF-1), and mitochondrial transcription factor A (mtTFA). The results showed that expression of cytochrome c oxidase, mtTFA, NRF-1, and PGC-1α was increased in As-BD compared with in healthy subjects. Treatment of primary keratinocytes with arsenic at concentrations lower than 1.0 μmol/L induced cell proliferation, along with enhanced mitochondrial biogenesis. Furthermore, we observed that the mitochondrial oxygen consumption rate and intracellular ATP level were increased in arsenic-treated keratinocytes. Blocking of mitochondrial function by oligomycin A (Complex V inhibitor) or knockdown of mtTFA by RNA interference abrogated arsenic-induced cell proliferation without affecting cyclin D1 expression. We concluded that mtTFA up-regulation, augmented mitochondrial biogenesis, and enhanced mitochondrial functions may contribute to arsenic-induced cell proliferation. Targeting mitochondrial biogenesis may help treat arsenical cancers at the stage of cell proliferation.

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

    NASA Technical Reports Server (NTRS)

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

    2006-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    2009-01-01

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

  18. Influence of radiofrequency radiation on chromosome aberrations in CHO cells and its interaction with DNA-damaging agents.

    PubMed

    Kerbacher, J J; Meltz, M L; Erwin, D N

    1990-09-01

    A limited number of contradictory reports have appeared in the literature about the ability of radiofrequency (rf) radiation to induce chromosome aberrations in different biological systems. The technical documentation associated with such reports is often absent or deficient. In addition, no information is available as to whether any additional genotoxic hazard would result from a simultaneous exposure of mammalian cells to rf radiation and a chemical which (by itself) induces chromosome aberrations. In the work described, we have therefore tested two hypotheses. The first is that rf radiation by itself, at power densities and exposure conditions which are higher than is consistent with accepted safety guidelines, can induce chromosome aberrations in mammalian cells. The second is that, during a simultaneous exposure to a chemical known to be genotoxic, rf radiation can affect molecules, biochemical processes, or cellular organelles, and thus result in an increase or decrease in chromosome aberrations. Mitomycin C (MMC) and Adriamycin (ADR) were selected because they act by different mechanisms, and because they might put normal cells at risk during combined-modality rf radiation (hyperthermia)-chemotherapy treatment of cancer. The studies were performed with suitable 37 degrees C and equivalent convection heating-temperature controls in a manner designed to discriminate between any thermal and possible nonthermal action. Radiofrequency exposures were conducted for 2 h under conditions resulting in measurable heating (a maximum increase of 3.2 degrees C), with pulsed-wave rf radiation at a frequency of 2450 MHz and an average net forward power of 600 W, resulting in an SAR of 33.8 W/kg. Treatments with MMC or ADR were for a total of 2.5 h and encompassed the 2-h rf radiation exposure period. The CHO cells from each of the conditions were subsequently analyzed for chromosome aberrations. In cells exposed to rf radiation alone, and where a maximum temperature of

  19. Aberrant expression of Xist in aborted porcine fetuses derived from somatic cell nuclear transfer embryos.

    PubMed

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

    2014-01-01

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

  20. Cadmium chloride strongly enhances cyclophosphamide-induced chromosome aberrations in mouse bone marrow cells

    SciTech Connect

    Pandurangarao, V.L.; Blazina, S.; Bherje, R.

    1997-10-01

    Earlier we reported that a single 5 mg cadmium chloride (CdCl{sub 2})/kg ip dose enhanced chromosome aberrations (ca) with 50 mg/kg cyclophosphamide (CP) in mouse bone marrow cells. In this report groups of 4 mice were injected ip with saline, 0.31, 0.62, 1.25, 2.5 or 5.0 mg/kg CdCl{sub 2}, followed by saline injections at 24 h. Other mice similarly uninjected at 0 h were injected with 50 mg/kg CP at 24 h. All the mice were injected ip with 4 mg colchicine/kg at 44 h. At 48 h the bone marrow cells were processed for chromosome spreads. After dissection, visual examination revealed obvious internal hemorrhaging of the testes at 1.25 CdCl{sub 2} mg/kg and higher doses. This effect was not further increased by CP treatment. The lowest ca enhancing dose of CdCl{sub 2} on CP was 0.625 mg/kg. Our hypothesis is that Cd replaces zinc presents in numerous DNA repair enzymes and proteins resulting in diminished repair. Subsequently, the excess of unrepaired DNA damage is seen as chromatid breaks, deletions, fragments and exchanges.

  1. Aberration corrected emittance exchange

    NASA Astrophysics Data System (ADS)

    Nanni, E. A.; Graves, W. S.

    2015-08-01

    Full exploitation of emittance exchange (EEX) requires aberration-free performance of a complex imaging system including active radio-frequency (rf) elements which can add temporal distortions. We investigate the performance of an EEX line where the exchange occurs between two dimensions with normalized emittances which differ by multiple orders of magnitude. The transverse emittance is exchanged into the longitudinal dimension using a double dogleg emittance exchange setup with a five cell rf deflector cavity. Aberration correction is performed on the four most dominant aberrations. These include temporal aberrations that are corrected with higher order magnetic optical elements located where longitudinal and transverse emittance are coupled. We demonstrate aberration-free performance of an EEX line with emittances differing by four orders of magnitude, i.e., an initial transverse emittance of 1 pm-rad is exchanged with a longitudinal emittance of 10 nm-rad.

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

    NASA Technical Reports Server (NTRS)

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

    2008-01-01

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

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

    SciTech Connect

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

    2007-05-15

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

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

    NASA Technical Reports Server (NTRS)

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

    2007-01-01

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

  5. An improved system for exposure of cultured mammalian cells to gaseous compounds in the chromosomal aberration assay.

    PubMed

    Asakura, Masumi; Sasaki, Toshiaki; Sugiyama, Toshie; Arito, Heihachiro; Fukushima, Shoji; Matsushima, Taijiro

    2008-04-30

    A gas exposure system using rotating vessels was improved for exposure of cultured mammalian cells to gaseous compounds in the chromosomal aberration assay. This system was composed of 12 square culture vessels, a device for preparation of air containing test gas, and positive and negative control gases at target concentrations and for supplying these gases to the culture vessels, and a roller apparatus in an incubator. Chinese hamster lung cells (CHL/IU) were grown on one side of the inner surface of the square culture vessel in the MEM medium. Immediately prior to exposure, the medium was changed to the modified MEM. Air in the culture vessel was replaced with air containing test gas, positive or negative control gas. Then, the culture vessels were rotated at 1.0 rpm. The monolayered culture cells were exposed to test gas during about 3/4 rotation at upper positions and alternatively immersed into the culture medium during about 1/4 rotation at lower positions. This system allowed the chromosomal aberration assay simultaneously at least at three different concentrations of a test gas together with positive and negative control gases with and without metabolic activations, and duplicate culture at each exposure concentration. Seven gaseous compounds, 1,3-butadiene, chlorodifluoromethane, ethyl chloride, methyl bromide, methyl chloride, propyne, and vinyl chloride, none of which has been tested to date, were tested on CHL/IU for the chromosomal aberration assay using this gas exposure system. All the compounds except chlorodifluoromethane showed positive responses of the structural chromosomal aberrations, whereas polyploidy was not induced by any of these gases. This improved gas exposure system proved to be useful for detecting chromosomal aberrations of gaseous compounds.

  6. An improved system for exposure of cultured mammalian cells to gaseous compounds in the chromosomal aberration assay.

    PubMed

    Asakura, Masumi; Sasaki, Toshiaki; Sugiyama, Toshie; Arito, Heihachiro; Fukushima, Shoji; Matsushima, Taijiro

    2008-04-30

    A gas exposure system using rotating vessels was improved for exposure of cultured mammalian cells to gaseous compounds in the chromosomal aberration assay. This system was composed of 12 square culture vessels, a device for preparation of air containing test gas, and positive and negative control gases at target concentrations and for supplying these gases to the culture vessels, and a roller apparatus in an incubator. Chinese hamster lung cells (CHL/IU) were grown on one side of the inner surface of the square culture vessel in the MEM medium. Immediately prior to exposure, the medium was changed to the modified MEM. Air in the culture vessel was replaced with air containing test gas, positive or negative control gas. Then, the culture vessels were rotated at 1.0 rpm. The monolayered culture cells were exposed to test gas during about 3/4 rotation at upper positions and alternatively immersed into the culture medium during about 1/4 rotation at lower positions. This system allowed the chromosomal aberration assay simultaneously at least at three different concentrations of a test gas together with positive and negative control gases with and without metabolic activations, and duplicate culture at each exposure concentration. Seven gaseous compounds, 1,3-butadiene, chlorodifluoromethane, ethyl chloride, methyl bromide, methyl chloride, propyne, and vinyl chloride, none of which has been tested to date, were tested on CHL/IU for the chromosomal aberration assay using this gas exposure system. All the compounds except chlorodifluoromethane showed positive responses of the structural chromosomal aberrations, whereas polyploidy was not induced by any of these gases. This improved gas exposure system proved to be useful for detecting chromosomal aberrations of gaseous compounds. PMID:18342567

  7. Identification of candidate target genes of genomic aberrations in esophageal squamous cell carcinoma

    PubMed Central

    Shen, Tian-Yun; Mei, Li-Li; Qiu, Yun-Tan; Shi, Zhi-Zhou

    2016-01-01

    The aim of the present study was to identify the candidate target genes of genomic aberrations in esophageal squamous cell carcinoma (ESCC). Array comparative genomic hybridization (CGH) and quantitative polymerase chain reaction were applied to analyze the copy number changes and expression level of candidate genes, respectively. Integrative analysis revealed that homozygous deletions of cyclin-dependent kinase inhibitor (CDKN) 2A and CDKN2B and gains of fascin actin-bundling protein 1 (FSCN1) and homer scaffolding protein 3 (HOMER3) occurred frequently in ESCC. The results demonstrated that the homozygous deletion of CDKN2A or CDKN2B was significantly associated with lymph node metastasis. Notably, the expression of CDKN2A and CDKN2B was lower in dysplasia than in normal esophageal epithelium. We also observed that the copy number increase of FSCN1 was significantly associated with pT, pN and pStage, and that the gain of HOMER3 was significantly linked with pN and pStage. We further revealed that FSCN1 and HOMER3 were overexpressed in ESCC, and that their overexpression was correlated with copy number increase. In conclusion, CDKN2A, CDKN2B, FSCN1 and HOMER3 are candidate cancer-associated genes and may play a tumorigenic role in ESCC.

  8. Identification of candidate target genes of genomic aberrations in esophageal squamous cell carcinoma

    PubMed Central

    Shen, Tian-Yun; Mei, Li-Li; Qiu, Yun-Tan; Shi, Zhi-Zhou

    2016-01-01

    The aim of the present study was to identify the candidate target genes of genomic aberrations in esophageal squamous cell carcinoma (ESCC). Array comparative genomic hybridization (CGH) and quantitative polymerase chain reaction were applied to analyze the copy number changes and expression level of candidate genes, respectively. Integrative analysis revealed that homozygous deletions of cyclin-dependent kinase inhibitor (CDKN) 2A and CDKN2B and gains of fascin actin-bundling protein 1 (FSCN1) and homer scaffolding protein 3 (HOMER3) occurred frequently in ESCC. The results demonstrated that the homozygous deletion of CDKN2A or CDKN2B was significantly associated with lymph node metastasis. Notably, the expression of CDKN2A and CDKN2B was lower in dysplasia than in normal esophageal epithelium. We also observed that the copy number increase of FSCN1 was significantly associated with pT, pN and pStage, and that the gain of HOMER3 was significantly linked with pN and pStage. We further revealed that FSCN1 and HOMER3 were overexpressed in ESCC, and that their overexpression was correlated with copy number increase. In conclusion, CDKN2A, CDKN2B, FSCN1 and HOMER3 are candidate cancer-associated genes and may play a tumorigenic role in ESCC. PMID:27698883

  9. Antimutagenic effects of piperine on cyclophosphamide-induced chromosome aberrations in rat bone marrow cells.

    PubMed

    Wongpa, Sareeya; Himakoun, Lakana; Soontornchai, Sarisak; Temcharoen, Punya

    2007-01-01

    Piperine is a major pungent substance and active component of black pepper (Piper nigrum Linn.) and long pepper (Piper longum Linn.). Both plants are used worldwide as household spices and condiments. They are also used as important ingredients in folklore medicine in many Asian countries. Therefore, it is of interest to study antimutagenic effects of piperine. In this study, its influence on chromosomes was investigated in rat bone marrow cells. Male Wistar rats were orally administered piperine at the doses of 100, 400 and 800 mg/kg body weight for 24 hours then challenged with cyclophosphamide at a dose of 50 mg/kg body weight by intraperitoneal injection. Twenty-four hours thereafter, all animals were sacrificed and bone marrow samples were collected for chromosomal analysis. The results demonstrated that piperine at a dose of 100 mg/kg body weight gave a statistically significant reduction in cyclophosphamide-induced chromosomal aberrations. In conclusion, piperine may have antimutagenic potential. The underlying molecular mechanisms now require attention.

  10. Genomic aberration patterns and expression profiles of squamous cell carcinomas of the vulva.

    PubMed

    Micci, Francesca; Panagopoulos, Ioannis; Haugom, Lisbeth; Dahlback, Hanne-Sofie S; Pretorius, Maria E; Davidson, Ben; Abeler, Vera M; Tropé, Claes G; Danielsen, Håvard E; Heim, Sverre

    2013-06-01

    Little is known about the genomic abnormalities of squamous cell carcinomas (SCC) of the vulva and how they correlate with gene expression. We determined the genomic and expression profiles of 15 such SCC using karyotyping, DNA ploidy analysis, arrayCGH, and expression arrays. Four of the five cases with clonal chromosomal aberrations found by G-banding showed highly abnormal karyotypes with multiple rearrangements. The imbalances scored by arrayCGH mapped to different chromosomes with losses being more common than gains. Frequent losses were scored from 3p and 8p whereas gains were frequent from 3q and 8q (loss of 8p with concomitant gain of 8q mostly occurred via 8q isochromosome formation). This is the first study of vulvar tumors using arrayCGH, and some frequent imbalances could be defined precisely. Of particular note were the sometimes large, sometimes small deletions of 3p and 9p which had minute areas in 3p14 and 9p23 as minimal commonly deleted regions. FHIT (3p14) and PTPRD (9p23) are the only genes here. They were both lost in seven cases, including homozygous losses of PTPRD in four tumors. Using qPCR we could demonstrate deregulation of the FHIT gene in tumor cells. Hence, this gene is likely to play a pathogenetic role in vulvar SCC tumorigenesis. Expression array analyses also identified a number of other genes whose expression profile was altered. Notable among the downregulated genes were MAL (in 2q11), KRT4 (in 12q13), and OLFM4 (in 13q14), whereas upregulated genes included SPRR2G (in 1q21.3) and S100A7A (in 1q21.3).

  11. Mechanisms of aberrant organization of growth plates in conditional transgenic mouse model of spondyloepiphyseal dysplasia associated with the R992C substitution in collagen II.

    PubMed

    Arita, Machiko; Fertala, Jolanta; Hou, Cheryl; Steplewski, Andrzej; Fertala, Andrzej

    2015-01-01

    Mutations in collagen II, a main structural protein of cartilage, are associated with various forms of spondyloepiphyseal dysplasia (SED), whose main features include aberrations of linear growth. Here, we analyzed the pathomechanisms responsible for growth alterations in transgenic mice with conditional expression of the R992C collagen II mutation. Specifically, we studied the alterations of the growth plates of mutant mice in which chondrocytes lacked their typical columnar arrangement. Our studies demonstrated that chondrocytes expressing the thermolabile R992C mutant collagen II molecules endured endoplasmic reticulum stress, had atypical polarization, and had reduced proliferation. Moreover, we demonstrated aberrant organization and morphology of primary cilia. Analyses of the extracellular collagenous deposits in mice expressing the R992C mutant collagen II molecules indicated their poor formation and distribution. By contrast, transgenic mice expressing wild-type collagen II and mice in which the expression of the transgene encoding the R992C collagen II was switched off were characterized by normal growth, and the morphology of their growth plates was correct. Our study with the use of a conditional mouse SED model not only indicates a direct relation between the observed aberration of skeletal tissues and the presence of mutant collagen II, but also identifies cellular and matrix elements of the pathomechanism of SED.

  12. Inter- and Intra-Chromosomal Aberrations in Human Cells Exposed in vitro to Space-like Radiations

    NASA Technical Reports Server (NTRS)

    Hada, Megumi; Cucinotta, F. A.; Gonda, S. R.; Wu, H.

    2005-01-01

    Energetic heavy ions pose a great health risk to astronauts in extended ISS and future exploration missions. High-LET heavy ions are particularly effective in causing various biological effects, including cell inactivation, genetic mutations and cancer induction. Most of these biological endpoints are closely related to chromosomal damage, which can be utilized as a biomarker for radiation insults. Previously, we had studied chromosome aberrations in human lymphocytes and fibroblasts induced by both low- and high-LET radiation using FISH and multicolor fluorescence in situ hybridization (mFISH) techniques. In this study, we exposed human cells in vitro to gamma rays and energetic particles of varying types and energies and dose rates, and analyzed chromosomal damages using the multicolor banding in situ hybridization (mBAND) procedure. Confluent human epithelial cells and lymphocytes were exposed to energetic heavy ions at NASA Space Radiation Laboratory (NSRL) at the Brookhaven National Laboratory (Upton, NY) or Cs-137 gamma radiation source at the Baylor College (Houston, TX). After colcemid and Calyculin A treatment, cells were fixed and painted with XCyte3 mBAND kit (MetaSystems) and chromosome aberrations were analyzed with mBAND analysis system (MetaSystems). With this technique, individually painted chromosomal bands on one chromosome allowed the identification of interchromosomal aberrations (translocation to unpainted chromosomes) and intrachromosomal aberrations (inversions and deletions within a single painted chromosome). The possible relationship between the frequency of inter- and intra-chromosomal exchanges and the track structure of radiation is discussed. The work was supported by the NASA Space Radiation Health Program.

  13. Chromosome Aberrations in Human Epithelial Cells Exposed Los Alamos High-Energy Secondary Neutrons: M-BAND Analysis

    NASA Technical Reports Server (NTRS)

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

    2007-01-01

    High-energy secondary neutrons, produced by the interaction of galactic cosmic rays (GCR) with the atmosphere, spacecraft structure and planetary surfaces, contribute a significant fraction to the dose equivalent radiation measurement in crew members and passengers of commercial aviation travel as well as astronauts in space missions. The Los Alamos Nuclear Science Center (LANSCE) neutron facility's 30L beam line (4FP30L-A/ICE House) is known to generate neutrons that simulate the secondary neutron spectrum of the Earth's atmosphere at high altitude. The neutron spectrum is also similar to that measured onboard spacecrafts like the MIR and the International Space Station (ISS). To evaluate the biological damage, we exposed human epithelial cells in vitro to the LANSCE neutron beams with an entrance dose rate of 2.5 cGy/hr, and studied the induction of chromosome aberrations that were identified with multicolor-banding in situ hybridization (mBAND) technique. With this technique, individually painted chromosomal bands on one chromosome allowed the identification of inter-chromosomal aberrations (translocation to unpainted chromosomes) and intra-chromosomal aberrations (inversions and deletions within a single painted chromosome). Compared to our previous results with gamma-rays and 600 MeV/nucleon Fe ions of high dose rate at NSRL (NASA Space Radiation Laboratory at Brookhaven National Laboratory), the neutron data from the LANSCE experiments showed significantly higher frequency of chromosome aberrations. However, detailed analysis of the inversion type revealed that all of the three radiation types in the study induced a low incidence of simple inversions. Most of the inversions in gamma-ray irradiated samples were accompanied by other types of intrachromosomal aberrations but few inversions were accompanied by interchromosomal aberrations. In contrast, neutrons and Fe ions induced a significant fraction of inversions that involved complex rearrangements of both

  14. Aberrant TAL1 activation is mediated by an interchromosomal interaction in human T-cell acute lymphoblastic leukemia.

    PubMed

    Patel, B; Kang, Y; Cui, K; Litt, M; Riberio, M S J; Deng, C; Salz, T; Casada, S; Fu, X; Qiu, Y; Zhao, K; Huang, S

    2014-02-01

    Long-range chromatin interactions control metazoan gene transcription. However, the involvement of intra- and interchromosomal interactions in development and oncogenesis remains unclear. TAL1/SCL is a critical transcription factor required for the development of all hematopoietic lineages; yet, aberrant TAL1 transcription often occurs in T-cell acute lymphoblastic leukemia (T-ALL). Here, we report that oncogenic TAL1 expression is regulated by different intra- and interchromosomal loops in normal hematopoietic and leukemic cells, respectively. These intra- and interchromosomal loops alter the cell-type-specific enhancers that interact with the TAL1 promoter. We show that human SET1 (hSET1)-mediated H3K4 methylations promote a long-range chromatin loop, which brings the +51 enhancer in close proximity to TAL1 promoter 1 in erythroid cells. The CCCTC-binding factor (CTCF) facilitates this long-range enhancer/promoter interaction of the TAL1 locus in erythroid cells while blocking the same enhancer/promoter interaction of the TAL1 locus in human T-cell leukemia. In human T-ALL, a T-cell-specific transcription factor c-Maf-mediated interchromosomal interaction brings the TAL1 promoter into close proximity with a T-cell-specific regulatory element located on chromosome 16, activating aberrant TAL1 oncogene expression. Thus, our study reveals a novel molecular mechanism involving changes in three-dimensional chromatin interactions that activate the TAL1 oncogene in human T-cell leukemia. PMID:23698277

  15. Sildenafil Therapy Normalizes the Aberrant Metabolomic Profile in the Comt−/− Mouse Model of Preeclampsia/Fetal Growth Restriction

    PubMed Central

    Stanley, Joanna L.; Sulek, Karolina; Andersson, Irene J.; Davidge, Sandra T.; Kenny, Louise C.; Sibley, Colin P.; Mandal, Rupasri; Wishart, David S.; Broadhurst, David I.; Baker, Philip N.

    2015-01-01

    Preeclampsia (PE) and fetal growth restriction (FGR) are serious complications of pregnancy, associated with greatly increased risk of maternal and perinatal morbidity and mortality. These complications are difficult to diagnose and no curative treatments are available. We hypothesized that the metabolomic signature of two models of disease, catechol-O-methyl transferase (COMT−/−) and endothelial nitric oxide synthase (Nos3−/−) knockout mice, would be significantly different from control C57BL/6J mice. Further, we hypothesised that any differences in COMT−/− mice would be resolved following treatment with Sildenafil, a treatment which rescues fetal growth. Targeted, quantitative comparisons of serum metabolic profiles of pregnant Nos3−/−, COMT−/− and C57BL/6J mice were made using a kit from BIOCRATES. Significant differences in 4 metabolites were observed between Nos3−/− and C57BL/6J mice (p < 0.05) and in 18 metabolites between C57BL/6J and COMT−/− mice (p < 0.05). Following treatment with Sildenafil, only 5 of the 18 previously identified differences in metabolites (p < 0.05) remained in COMT−/− mice. Metabolomic profiling of mouse models is possible, producing signatures that are clearly different from control animals. A potential new treatment, Sildenafil, is able to normalize the aberrant metabolomic profile in COMT−/− mice; as this treatment moves into clinical trials, this information may assist in assessing possible mechanisms of action. PMID:26667607

  16. Aberrant Circulating Th17 Cells in Patients with B-Cell Non-Hodgkin's Lymphoma.

    PubMed

    Lu, Ting; Yu, Shuang; Liu, Yan; Yin, Congcong; Ye, Jingjing; Liu, Zhi; Ma, Daoxin; Ji, Chunyan

    2016-01-01

    Non-Hodgkin's lymphomas (NHLs) are a heterogeneous group of neoplasm in which 90% are B-cell lymphomas and 10% T-cell lymphomas. Although T-helper 17 (Th17) cells have been implicated to be essential in the pathogenesis of autoimmune and inflammatory diseases, its role in B-cell non-Hodgkin's lymphoma (B-NHL) remains unknown. In this study, we observed a significantly decreased frequency of Th17 cells in peripheral blood from B-NHL patients compared with healthy individuals, accompanied with increased Th1 cells. IL-17AF plasma levels were remarkably decreased in B-NHL patients, accompanied with undetectable IL-17FF and unchangeable IL-17AA. Moreover, Th17 and Th1 cells became normalized after one or two cycles of chemotherapy. Interestingly, in B-NHL, circulating Th17 cells frequencies were significantly higher in relapsed patients than those in untreated patients or normal individuals. Meanwhile, there was no statistical difference regarding the frequencies of Th1 cells between relapsed and untreated patients. Taken these data together, circulating Th17 subset immune response may be associated with the response of patients to treatment and with different stages of disease. PMID:26812681

  17. Aberrant immunoglobulin class switch recombination and switch translocations in activated B cell-like diffuse large B cell lymphoma.

    PubMed

    Lenz, Georg; Nagel, Inga; Siebert, Reiner; Roschke, Anna V; Sanger, Warren; Wright, George W; Dave, Sandeep S; Tan, Bruce; Zhao, Hong; Rosenwald, Andreas; Muller-Hermelink, Hans Konrad; Gascoyne, Randy D; Campo, Elias; Jaffe, Elaine S; Smeland, Erlend B; Fisher, Richard I; Kuehl, W Michael; Chan, Wing C; Staudt, Louis M

    2007-03-19

    To elucidate the mechanisms underlying chromosomal translocations in diffuse large B cell lymphoma (DLBCL), we investigated the nature and extent of immunoglobulin class switch recombination (CSR) in these tumors. We used Southern blotting to detect legitimate and illegitimate CSR events in tumor samples of the activated B cell-like (ABC), germinal center B cell-like (GCB), and primary mediastinal B cell lymphoma (PMBL) subgroups of DLBCL. The frequency of legitimate CSR was lower in ABC DLBCL than in GCB DLBCL and PMBL. In contrast, ABC DLBCL had a higher frequency of internal deletions within the switch mu (Smu) region compared with GCB DLBCL and PMBL. ABC DLBCLs also had frequent deletions within Sgamma and other illegitimate switch recombinations. Sequence analysis revealed ongoing Smu deletions within ABC DLBCL tumor clones, which were accompanied by ongoing duplications and activation-induced cytidine deaminase-dependent somatic mutations. Unexpectedly, short fragments derived from multiple chromosomes were interspersed within Smu in one case. These findings suggest that ABC DLBCLs have abnormalities in the regulation of CSR that could predispose to chromosomal translocations. Accordingly, aberrant switch recombination was responsible for translocations in ABC DLBCLs involving BCL6, MYC, and a novel translocation partner, SPIB. PMID:17353367

  18. Defective quorum sensing of acute lymphoblastic leukemic cells: evidence of collective behavior of leukemic populations as semi-autonomous aberrant ecosystems.

    PubMed

    Patel, Sapan J; Dao, Su; Darie, Costel C; Clarkson, Bayard D

    2016-01-01

    Quorum sensing (QS) is a generic term used to describe cell-cell communication and collective decision making by bacterial and social insects to regulate the expression of specific genes in controlling cell density and other properties of the populations in response to nutrient supply or changes in the environment. QS mechanisms also have a role in higher organisms in maintaining homeostasis, regulation of the immune system and collective behavior of cancer cell populations. In the present study, we used a p190(BCR-ABL) driven pre-B acute lymphoblastic leukemia (ALL3) cell line derived from the pleural fluid of a terminally ill patient with ALL to test the QS hypothesis in leukemia. ALL3 cells don't grow at low density (LD) in liquid media but grow progressively faster at increasingly high cell densities (HD) in contrast to other established leukemic cell lines that grow well at very low starting cell densities. The ALL3 cells at LD are poised to grow but shortly die without additional stimulation. Supernates of ALL3 cells (HDSN) and some other primary cells grown at HD stimulate the growth of the LD ALL3 cells without which they won't survive. To get further insight into the activation processes we performed microarray analysis of the LD ALL3 cells after stimulation with ALL3 HDSN at days 1, 3, and 6. This screen identified several candidate genes, and we linked them to signaling networks and their functions. We observed that genes involved in lipid, cholesterol, fatty acid metabolism, and B cell activation are most up- or down-regulated upon stimulation of the LD ALL3 cells using HDSN. We also discuss other pathways that are differentially expressed upon stimulation of the LD ALL3 cells. Our findings suggest that the Ph+ ALL population achieves dominance by functioning as a collective aberrant ecosystem subject to defective quorum-sensing regulatory mechanisms. PMID:27429840

  19. Defective quorum sensing of acute lymphoblastic leukemic cells: evidence of collective behavior of leukemic populations as semi-autonomous aberrant ecosystems

    PubMed Central

    Patel, Sapan J; Dao, Su; Darie, Costel C; Clarkson, Bayard D

    2016-01-01

    Quorum sensing (QS) is a generic term used to describe cell-cell communication and collective decision making by bacterial and social insects to regulate the expression of specific genes in controlling cell density and other properties of the populations in response to nutrient supply or changes in the environment. QS mechanisms also have a role in higher organisms in maintaining homeostasis, regulation of the immune system and collective behavior of cancer cell populations. In the present study, we used a p190BCR-ABL driven pre-B acute lymphoblastic leukemia (ALL3) cell line derived from the pleural fluid of a terminally ill patient with ALL to test the QS hypothesis in leukemia. ALL3 cells don’t grow at low density (LD) in liquid media but grow progressively faster at increasingly high cell densities (HD) in contrast to other established leukemic cell lines that grow well at very low starting cell densities. The ALL3 cells at LD are poised to grow but shortly die without additional stimulation. Supernates of ALL3 cells (HDSN) and some other primary cells grown at HD stimulate the growth of the LD ALL3 cells without which they won’t survive. To get further insight into the activation processes we performed microarray analysis of the LD ALL3 cells after stimulation with ALL3 HDSN at days 1, 3, and 6. This screen identified several candidate genes, and we linked them to signaling networks and their functions. We observed that genes involved in lipid, cholesterol, fatty acid metabolism, and B cell activation are most up- or down-regulated upon stimulation of the LD ALL3 cells using HDSN. We also discuss other pathways that are differentially expressed upon stimulation of the LD ALL3 cells. Our findings suggest that the Ph+ ALL population achieves dominance by functioning as a collective aberrant ecosystem subject to defective quorum-sensing regulatory mechanisms. PMID:27429840

  20. Comparison of cell repair mechanisms by means of chromosomal aberration induced by proton and gamma irradiation - preliminary results

    NASA Astrophysics Data System (ADS)

    Kowalska, A.; Czerski, K.; Kaczmarski, M.; Lewocki, M.; Masojć, B.; Łukowiak, A.

    2015-03-01

    DNA damage of peripheral blood lymphocytes exposed to gamma and proton irradiation is studied by means of chromosome aberrations to validate the efficiency of the repair mechanisms of individual cells. A new method based on an observed deviation from the Poisson statistics of the chromosome aberration number is applied for estimation of a repair factor ( RF) defined as a ratio between originally damaged cells to the amount of finally observed aberrations. The repair factors are evaluated by studying the variance of individual damage factors in a collective of healthy persons at a given dose as well as by using the chi-square analysis for the dose-effect curves. The blood samples from fifteen donors have been irradiated by Co60 gamma rays and from nine persons by 150 MeV protons with different doses up to 2 Gy. A standard extraction of lymphocyte has been used whereby dicentrics, acentrics and rings have been scored under a microscope. The RF values determined for the proton radiation are slightly larger than for gamma rays, indicating that up to 70% DNA double strand breaks can be repaired.

  1. Aberrant expression of the CHFR prophase checkpoint gene in human B-cell non-Hodgkin lymphoma.

    PubMed

    Song, Aiqin; Ye, Junli; Zhang, Kunpeng; Yu, Hongsheng; Gao, Yanhua; Wang, Hongfang; Sun, Lirong; Xing, Xiaoming; Yang, Kun; Zhao, Min

    2015-05-01

    Checkpoint with FHA and Ring Finger (CHFR) is a checkpoint protein that reportedly initiates a cell cycle delay in response to microtubule stress during prophase in mitosis, which has become an interesting target for understanding cancer pathogenesis. Recently, aberrant methylation of the CHFR gene associated with gene silencing has been reported in several cancers. In the present study, we examined the expression of CHFR in B-cell non-Hodgkin lymphoma (B-NHL) in vitro and in vivo. Our results showed that the expression level of CHFR mRNA and protein was reduced in B-NHL tissue samples and B cell lines. Furthermore, CHFR methylation was detected in 39 of 122 B-NHL patients, which was not found in noncancerous reactive hyperplasia of lymph node (RH) tissues. CHFR methylation correlated with the reduced expression of CHFR, high International Prognostic Index (IPI) scores and later pathologic Ann Arbor stages of B-NHL. Treatment with demethylation reagent, 5-Aza-dC, could eliminate the hypermethylation of CHFR, enhance CHFR expression and cell apoptosis and inhibit the cell proliferation of Raji cells, which could be induced by high expression of CHFR in Raji cells. Our results indicated that aberrant methylation of CHFR may be associated with the pathogenesis, progression for B-NHL, which might be a novel molecular marker as prognosis and treatment for B-NHL. PMID:25798877

  2. Aberrantly activated Gli2-KIF20A axis is crucial for growth of hepatocellular carcinoma and predicts poor prognosis

    PubMed Central

    Shi, Chao; Huang, Dengliang; Lu, Nonghua; Chen, Dan; Zhang, Minhong; Yan, Yehong; Deng, Libin; Lu, Quqin; Lu, Hua; Luo, Shiwen

    2016-01-01

    Glioma-associated oncogene 2 (Gli2), a primary transcriptional regulator of Hedgehog (Hh) signaling, is essential for hepatocellular carcinoma (HCC) growth and survival. However, the underlying molecular mechanism and crucial downstream targets of Gli2 in human HCC are not fully understood. Here, we report the identification of kinesin family member 20A (KIF20A) as a novel downstream target of Gli2, which is important for HCC proliferation and tumor growth. Inhibition of Hh signaling leads to a remarkable decrease of KIF20A expression in HCC cells, whereas overexpression of Gli2 elevates KIF20A expression by activating Forkhead Box M1 (FoxM1)-MMB complex-mediated transcription of this kinesin gene. Gli2-induced HCC cell growth requires enhanced expression of KIF20A, and knockdown of Gli2 or KIF20A represses the proliferation of HCC cells in vitro and in vivo. Correlated with these results, analyses of clinical HCC samples show that Gli2, FoxM1 and KIF20A are highly elevated in primary HCC samples and represent significant risk factors for HCC recurrence and survival. Conclusion: KIF20A is an important downstream target gene of Hh signaling. And, the Gli2-KIF20A axis is essential for the proliferation and growth of human HCC cells. Our study also suggests Gli2-KIF20A axis as a potential target for future therapeutic intervention and as an independent prognostic biomarker for HCC. PMID:27036048

  3. Phytochemicals attenuating aberrant activation of ß-catenin in cancer cells

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phytochemicals are a rich source of chemoprevention agents but their effects on modulating the Wnt/ß-catenin signaling pathway have remained largely uninvestigated. Aberrantly activated Wnt signaling can result in the abnormal stabilization of ß-catenin, a key causative step in a broad spectrum of c...

  4. Reduced susceptibility to azoxymethane-induced aberrant crypt foci formation and colon cancer in growth hormone deficient rats

    PubMed Central

    Carroll, Robert E.; Goodlad, Robert A.; Poole, Aleksandra J.; Tyner, Angela L.; Robey, R. Brooks; Swanson, Steven M.; Unterman, Terry G.

    2010-01-01

    Objectives To evaluate the role of GH in colon carcinogenesis, we examined the formation of aberrant crypt foci (ACFs) and tumor development in wild type (WT) and GH-deficient, spontaneous dwarf rats (SDRs) exposed to the carcinogen azoxymethane (AOM). Design ACF were quantified by stereomicroscopy and tumor number and weights were recorded for each animal. Cell proliferation was measured by vincristine metaphase arrest, flow cytometry, and bromode-oxyuridine (BrdU) incorporation. Apoptosis was measured by TUNEL staining and cleaved caspase-3 immunohistochemistry. IGF-I was measured by radioimmunoassay (RIA). Hexokinase activity was measured by spectrophotometric assay. PARP cleavage, and IGF-IR, and p27kip/cip expression were measured by Western blotting. Results ACFs detected by stereomicroscopy were markedly reduced (~85%) in SDRs vs. WT rats at 10, 25, and 28 weeks after AOM. Tumor incidence, number, and weight also were reduced in SDR vs. WT animals. AOM treatment increased cell proliferation in the distal colon (where tumors occur) of WT rats but not SDRs, and these changes corresponded to increased ACF and tumor formation. Apoptosis rates were similar in AOM-treated WT and SDRs. Alterations in serum IGF-I levels may contribute to differences in the proliferative response to AOM and decreased ACF formation in SDR vs. WT rats. Conclusions We conclude that early neoplastic lesions (ACFs) were reduced in GH-deficient animals. This effect corresponds with differences in AOM-induced proliferation, but not apoptosis. These data indicate that GH is required for the full effect of AOM on colon ACF and tumor development, and that the SDR rat is a promising model for studies regarding the role of GH/IGF system in the initiation and promotion of colon cancer. PMID:19406679

  5. Increased miR-374b promotes cell proliferation and the production of aberrant glycosylated IgA1 in B cells of IgA nephropathy.

    PubMed

    Hu, Shuai; Bao, Hao; Xu, Xiaodong; Zhou, Xianguang; Qin, Weisong; Zeng, Caihong; Liu, Zhihong

    2015-12-21

    The number of B cells is increased and the O-glycans of IgA1 are incompletely galactosylated in IgA nephropathy (IgAN). Here we report that expression of phosphatase and tensin homolog (PTEN) and Cosmc is decreased in B cells, and correlates with B cell number and the aberrant glycosylation of IgA1 in IgAN. Patients with IgAN exhibit higher miR-374b in B cells compared to controls. We show that miR-374b targets PTEN and Cosmc by luciferase assays and western blot analysis. Inhibition of miR-374b increased PTEN and Cosmc expression, and prevented cell proliferation and aberrant glycosylation of IgA1, thus representing a new therapeutic approach for IgAN.

  6. Suppression of adiponectin by aberrantly glycosylated IgA1 in glomerular mesangial cells in vitro and in vivo.

    PubMed

    Inoue, Tatsuyuki; Sugiyama, Hitoshi; Kitagawa, Masashi; Takiue, Keiichi; Morinaga, Hiroshi; Ogawa, Ayu; Kikumoto, Yoko; Kitamura, Shinji; Maeshima, Yohei; Makino, Hirofumi

    2012-01-01

    The pathogenesis of IgA nephropathy (IgAN) may be associated with the mesangial deposition of aberrantly glycosylated IgA1. To identify mediators affected by aberrantly glycosylated IgA1 in cultured human mesangial cells (HMCs), we generated enzymatically modified desialylated and degalactosylated (deSial/deGal) IgA1. The state of deglycosylated IgA1 was confirmed by lectin binding to Helix aspersa (HAA) and Sambucus nigra (SNA). In the cytokine array analysis, 52 proteins were upregulated and 34 were downregulated in HMCs after stimulation with deSial/deGal IgA1. Among them, the secretion of adiponectin was suppressed in HMCs after stimulation with deSial/deGal IgA1. HMCs expressed mRNAs for adiponectin and its type 1 receptor, but not the type 2 receptor. Moreover, we revealed a downregulation of adiponectin expression in the glomeruli of renal biopsy specimens from patients with IgAN compared to those with lupus nephritis. We also demonstrated that aberrantly glycosylated IgA1 was deposited in the mesangium of patients with IgAN by dual staining of HAA and IgA. Moreover, the urinary HAA/SNA ratio of lectin binding was significantly higher in IgAN compared to other kidney diseases. Since adiponectin has anti-inflammatory effects, including the inhibition of adhesion molecules and cytokines, these data suggest that the local suppression of this adipokine by aberrantly glycosylated IgA1 could be involved in the regulation of glomerular inflammation and sclerosis in IgAN.

  7. Involvement of aberrant DNA methylation on reduced expression of lysophosphatidic acid receptor-1 gene in rat tumor cell lines

    SciTech Connect

    Tsujiuchi, Toshifumi . E-mail: ttujiuch@life.kindai.ac.jp; Shimizu, Kyoko; Onishi, Mariko; Sugata, Eriko; Fujii, Hiromasa; Mori, Toshio; Honoki, Kanya; Fukushima, Nobuyuki

    2006-10-27

    Lysophosphatidic acid (LPA) is a bioactive phospholipid that stimulates cell proliferation, migration, and protects cells from apoptosis. It interacts with specific G protein-coupled transmembrane receptors. Recently, it has been reported that alterations of LPA receptor expression might be important in the malignant transformation of tumor cells. Therefore, to assess an involvement of DNA methylation in reduced expression of the LPA receptor-1 (lpa1) gene, we investigated the expression of the lpa1 gene and its DNA methylation patterns in rat tumor cell lines. Both rat brain-derived neuroblastoma B103 and liver-derived hepatoma RH7777 cells used in this study indicated no expression of lpa1. For the analysis of methylation status, bisulfite sequencing was performed with B103 and RH7777 cells, comparing with other lpa1 expressed cells and normal tissues of brain and liver. The lpa1 expressed cells and tissues were all unmethylated in this region of lpa1. In contrast, both B103 and RH7777 cells were highly methylated, correlating with reduced expression of the lpa1. Treatment with 5-aza 2'-deoxycytidine induced expression of lpa1 gene in B103 and RH7777 cells after 24 h. In RH7777 cells treated with 5-aza 2'-deoxycytidine, stress fiber formation was also observed in response to LPA in RH7777 cells, but not in untreated RH7777 cells. These results suggest that aberrant DNA methylation of the lpa1 gene may be involved in its reduced expression in rat tumor cells.

  8. Aberrant production of extracellular matrix proteins and dysfunction in kidney endothelial cells with a short duration of diabetes.

    PubMed

    Grutzmacher, Cathy; Park, SunYoung; Zhao, Yun; Morrison, Margaret E; Sheibani, Nader; Sorenson, Christine M

    2013-01-01

    Diabetic nephropathy is the most common cause of end-stage renal disease and is a major risk factor for cardiovascular disease. In the United States, microvascular complications during diabetic nephropathy contribute to high morbidity and mortality rates. However, the cell-autonomous impact of diabetes on kidney endothelial cell function requires further investigation. Male Akita/+ [autosomal dominant mutation in the insulin II gene (Ins2)] mice reproducibly develop diabetes by 4 wk of age. Here, we examined the impact a short duration of diabetes had on kidney endothelial cell function. Kidney endothelial cells were prepared from nondiabetic and diabetic mice (4 wk of diabetes) to delineate the early changes in endothelial cell function. Kidney endothelial cells from Akita/+ mice following 4 wk of diabetes demonstrated aberrant expression of extracellular matrix proteins including decreased osteopontin and increased fibronectin expression which correlated with increased α5-integrin expression. These changes were associated with the attenuation of migration and capillary morphogenesis. Kidney endothelial cells from Akita/+ mice had decreased VEGF levels but increased levels of endothelial nitric oxide synthase(eNOS) and NO, suggesting uncoupling of VEGF-mediated NO production. Knocking down eNOS expression in Akita/+ kidney endothelial cells increased VEGF expression, endothelial cell migration, and capillary morphogenesis. Furthermore, attenuation of sprouting angiogenesis of aortas from Akita/+ mice with 8 wk of diabetes was restored in the presence of the antioxidant N-acetylcysteine. These studies demonstrate that aberrant endothelial cell function with a short duration of diabetes may set the stage for vascular dysfunction and rarefaction at later stages of diabetes.

  9. Brahmarasayana protects against Ethyl methanesulfonate or Methyl methanesulfonate induced chromosomal aberrations in mouse bone marrow cells

    PubMed Central

    2012-01-01

    Background Ayurveda, the traditional Indian system of medicine has given great emphasis to the promotion of health. Rasayana is one of the eight branches of Ayurveda which refers to rejuvenant therapy. It has been reported that rasayanas have immuno-modulatory, antioxidant and antitumor functions, however, the genotoxic potential and modulation of DNA repair of many rasayanas have not been evaluated. Methods The present study assessed the role of Brahmarasayana (BR) on Ethyl methanesulfonate (EMS)-and Methyl methanesulfonate (MMS)-induced genotoxicity and DNA repair in in vivo mouse test system. The mice were orally fed with BR (5 g or 8 mg / day) for two months and 24 h later EMS or MMS was given intraperitoneally. The genotoxicity was analyzed by chromosomal aberrations, sperm count, and sperm abnormalities. Results The results have revealed that BR did not induce significant chromosomal aberrations when compared to that of the control animals (p >0.05). On the other hand, the frequencies of chromosomal aberrations induced by EMS (240 mg / kg body weight) or MMS (125 mg / kg body weight) were significantly higher (p<0.05) to that of the control group. The treatment of BR for 60 days and single dose of EMS or MMS on day 61, resulted in significant (p <0.05) reduction in the frequency of chromosomal aberrations in comparison to EMS or MMS treatment alone, indicating a protective effect of BR. Constitutive base excision repair capacity was also increased in BR treated animals. Conclusion The effect of BR, as it relates to antioxidant activity was not evident in liver tissue however rasayana treatment was observed to increase constitutive DNA base excision repair and reduce clastogenicity. Whilst, the molecular mechanisms of such repair need further exploration, this is the first report to demonstrate these effects and provides further evidence for the role of brahmarasayana in the possible improvement of quality of life. PMID:22853637

  10. Icariside II, a natural mTOR inhibitor, disrupts aberrant energy homeostasis via suppressing mTORC1-4E-BP1 axis in sarcoma cells.

    PubMed

    Zhang, Chao; Yang, Lei; Geng, Ya-di; An, Fa-Liang; Xia, Yuan-Zheng; Guo, Chao; Luo, Jian-Guang; Zhang, Lu-Yong; Guo, Qing-Long; Kong, Ling-Yi

    2016-05-10

    The aberrant energy homeostasis that characterized by high rate of energy production (glycolysis) and energy consumption (mRNA translation) is associated with the development of cancer. As mammalian target of rapamycin (mTOR) is a critical regulator of aberrant energy homeostasis, it is an attractive target for anti-tumor intervention. The flavonoid compound Icariside II (IS) is a natural mTOR inhibitor derived from Epimedium. Koreanum. Herein, we evaluate the effect of IS on aberrant energy homeostasis. The reduction of glycolysis and mRNA translation in U2OS (osteosarcoma), S180 (fibrosarcoma) and SW1535 (chondrosarcoma) cells observed in our study, indicate that, IS inhibits aberrant energy homeostasis. This inhibition is found to be due to suppression of mammalian target of rapamycin complex 1 (mTORC1)-eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1) axis through blocking the assembly of mTORC1. Furthermore, IS inhibits the cap-dependent translation of c-myc through mTORC1-4E-BP1 axis which links the relationship between mRNA translation and glycolysis. Inhibition of aberrant energy homeostasis by IS, contributes to its in vitro and in vivo anti-proliferation activity. These data indicate that IS disrupts aberrant energy homeostasis of sarcoma cells through suppression of mTORC1-4E-BP1 axis, providing a novel mechanism of IS to inhibit cell proliferation in sarcoma cells.

  11. Icariside II, a natural mTOR inhibitor, disrupts aberrant energy homeostasis via suppressing mTORC1-4E-BP1 axis in sarcoma cells.

    PubMed

    Zhang, Chao; Yang, Lei; Geng, Ya-di; An, Fa-Liang; Xia, Yuan-Zheng; Guo, Chao; Luo, Jian-Guang; Zhang, Lu-Yong; Guo, Qing-Long; Kong, Ling-Yi

    2016-05-10

    The aberrant energy homeostasis that characterized by high rate of energy production (glycolysis) and energy consumption (mRNA translation) is associated with the development of cancer. As mammalian target of rapamycin (mTOR) is a critical regulator of aberrant energy homeostasis, it is an attractive target for anti-tumor intervention. The flavonoid compound Icariside II (IS) is a natural mTOR inhibitor derived from Epimedium. Koreanum. Herein, we evaluate the effect of IS on aberrant energy homeostasis. The reduction of glycolysis and mRNA translation in U2OS (osteosarcoma), S180 (fibrosarcoma) and SW1535 (chondrosarcoma) cells observed in our study, indicate that, IS inhibits aberrant energy homeostasis. This inhibition is found to be due to suppression of mammalian target of rapamycin complex 1 (mTORC1)-eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1) axis through blocking the assembly of mTORC1. Furthermore, IS inhibits the cap-dependent translation of c-myc through mTORC1-4E-BP1 axis which links the relationship between mRNA translation and glycolysis. Inhibition of aberrant energy homeostasis by IS, contributes to its in vitro and in vivo anti-proliferation activity. These data indicate that IS disrupts aberrant energy homeostasis of sarcoma cells through suppression of mTORC1-4E-BP1 axis, providing a novel mechanism of IS to inhibit cell proliferation in sarcoma cells. PMID:27056897

  12. Icariside II, a natural mTOR inhibitor, disrupts aberrant energy homeostasis via suppressing mTORC1-4E-BP1 axis in sarcoma cells

    PubMed Central

    Zhang, Chao; Yang, Lei; Geng, Ya-di; An, Fa-liang; Xia, Yuan-zheng; Guo, Chao; Luo, Jian-guang; Zhang, Lu-yong; Guo, Qing-long; Kong, Ling-yi

    2016-01-01

    The aberrant energy homeostasis that characterized by high rate of energy production (glycolysis) and energy consumption (mRNA translation) is associated with the development of cancer. As mammalian target of rapamycin (mTOR) is a critical regulator of aberrant energy homeostasis, it is an attractive target for anti-tumor intervention. The flavonoid compound Icariside II (IS) is a natural mTOR inhibitor derived from Epimedium. Koreanum. Herein, we evaluate the effect of IS on aberrant energy homeostasis. The reduction of glycolysis and mRNA translation in U2OS (osteosarcoma), S180 (fibrosarcoma) and SW1535 (chondrosarcoma) cells observed in our study, indicate that, IS inhibits aberrant energy homeostasis. This inhibition is found to be due to suppression of mammalian target of rapamycin complex 1 (mTORC1)-eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1) axis through blocking the assembly of mTORC1. Furthermore, IS inhibits the cap-dependent translation of c-myc through mTORC1-4E-BP1 axis which links the relationship between mRNA translation and glycolysis. Inhibition of aberrant energy homeostasis by IS, contributes to its in vitro and in vivo anti-proliferation activity. These data indicate that IS disrupts aberrant energy homeostasis of sarcoma cells through suppression of mTORC1-4E-BP1 axis, providing a novel mechanism of IS to inhibit cell proliferation in sarcoma cells. PMID:27056897

  13. Biomarker for Space Radiation Risk: Painting Analysis of Chromosome Aberrations Induced by Energetic Heavy Ions in Human Cells

    NASA Technical Reports Server (NTRS)

    Hada, Megumi; George, Kerry; Cucinotta, Francis A.; Wu, Honglu

    2007-01-01

    Energetic heavy ions pose a great health risk to astronauts in extended ISS and future Lunar and Mars missions. High-LET heavy ions are particularly effective in causing various biological effects, including cell inactivation, genetic mutations, cataracts and cancer induction. Most of these biological endpoints are closely related to chromosomal damage, which can be utilized as a biomarker for radiation insults. Over the years, we have studied chromosomal damage in human fibroblast, epithelia and lymphocyte cells exposed in vitro to energetic charged particles generated at several accelerator facilities in the world. We have also studied chromosome aberrations in astronaut s peripheral blood lymphocytes before and after space flight. Various fluorescence in situ hybridization painting techniques have been used to identify from only the telomere region of the chromosome to every chromosome in a human cell. We will summarize the results of the investigations, and discuss the unique radiation signatures and biomarkers for space radiation exposure.

  14. PAX8 is transcribed aberrantly in cervical tumors and derived cell lines due to complex gene rearrangements.

    PubMed

    López-Urrutia, Eduardo; Pedroza-Torres, Abraham; Fernández-Retana, Jorge; De Leon, David Cantu; Morales-González, Fermín; Jacobo-Herrera, Nadia; Peralta-Zaragoza, Oscar; García-Mendez, Jorge; García-Castillo, Verónica; Bautista-Isidro, Osvaldo; Pérez-Plasencia, Carlos

    2016-07-01

    The transcription factor PAX8, a member of the paired box-containing gene family with an important role in embryogenesis of the kidney, thyroid gland and nervous system, has been described as a biomarker in tumors of the thyroid, parathyroid, kidney and thymus. The PAX8 gene gives rise to four isoforms, through alternative mRNA splicing, but the splicing pattern in tumors is not yet established. Cervical cancer has a positive expression of PAX8; however, there is no available data determining which PAX8 isoform or isoforms are present in cervical cancer tissues as well as in cervical carcinoma-derived cell lines. Instead of a differential pattern of splicing isoforms, we found numerous previously unreported PAX8 aberrant transcripts ranging from 378 to 542 bases and present in both cervical carcinoma-derived cell lines and tumor samples. This is the first report of PAX8 aberrant transcript production in cervical cancer. Reported PAX8 isoforms possess differential transactivation properties; therefore, besides being a helpful marker for detection of cancer, PAX8 isoforms can plausibly exert differential regulation properties during carcinogenesis. PMID:27175788

  15. The inhibition of CHO-K1-BH4 cell proliferation and induction of chromosomal aberrations by brevetoxins in vitro

    PubMed Central

    Sayer, A.N.; Hu, Q.; Bourdelais, A.J.; Baden, D.G.; Gibson, J.E.

    2009-01-01

    Brevetoxins (PbTxs) are highly potent trans-syn polyether neurotoxins produced during blooms of several species of marine dinoflagellates, most notably Karenia brevis. These neurotoxins act on voltage-sensitive sodium channels prolonging the active state. During red tides, the commercial fishing and tourism industries experience millions of dollars of lost revenue. Human consumption of shellfish contaminated with PbTxs results in neurotoxic shellfish poisoning (NSP). Additionally, blooms of K. brevis are potentially responsible for adverse human health effects such as respiratory irritation and airway constriction in coastal residents. There is little information regarding the full range of potential toxic effects caused by PbTxs. Recent evidence suggests that PbTxs are genotoxic substances. The purpose of this study was to determine if PbTxs could induce chromosomal aberrations and inhibit cellular proliferation in CHO-K1-BH4 cells, and if so, could the damage be negated or reduced by the PbTx antagonist brevenal. Results from the chromosomal aberrations assay demonstrated that PbTxs are potent inducers of CHO-K1-BH4 chromosome damage. Results from the inhibition of cellular proliferation assays demonstrated that PbTxs inhibit the ability of CHO-K1-BH4 cells to proliferate, an effect which can be reduced with brevenal. PMID:16487644

  16. Persistent Simian Immunodeficiency Virus Infection Drives Differentiation, Aberrant Accumulation, and Latent Infection of Germinal Center Follicular T Helper Cells

    PubMed Central

    Xu, Huanbin; Wang, Xiaolei; Malam, Naomi; Aye, Pyone P.; Alvarez, Xavier; Lackner, Andrew A.

    2015-01-01

    ABSTRACT CD4+ follicular T helper (Tfh) cells play a prominent role in humoral immune responses, but the mechanisms of their accumulation and infection in AIDS remain unclear. Here we found that germinal center (GC) Tfh cells, defined here as CXCR5+ PD-1HIGH CD4+ T cells, do not express the HIV coreceptor CCR5 yet serve as a latent reservoir in GCs. With disease progression, an expansion of GC Tfh cells is accompanied by increases in dysfunctional CD8+ T cells. In contrast, Tfh precursor (CXCR5− CD4+ T) cells in lymph nodes do express CCR5 and differentiate into GC Tfh cells following interleukin-6 (IL-6) and IL-21 stimulation, and viral DNA is detectable in fully differentiated GC Tfh cells ex vivo. This suggests that SIV-infected GC Tfh cells may be derived from Tfh precursor cell subsets that become infected in marginal zones and then migrate into GCs as fully mature GC Tfh cells that serve as persistent virus reservoirs. These findings suggest that viral persistence in lymph nodes drives compensatory differentiation, aberrant accumulation, and latent infection of GC Tfh cells, resulting in marked impairment of humoral immune responses. IMPORTANCE Generation of antibodies that can effectively eliminate viruses requires interactions of B cells with highly specialized T cells in GCs of lymphoid tissues called follicular T helper cells. Here we show that in simian immunodeficiency virus infection, these cells are initially infected in a precursor stage that leads to alterations in their homing, accumulation, and function that may be responsible for the inability of human immunodeficiency virus-infected patients to generate effective antibody responses. PMID:26608323

  17. Shared clonal cytogenetic abnormalities in aberrant mast cells and leukemic myeloid blasts detected by single nucleotide polymorphism microarray-based whole-genome scanning.

    PubMed

    Frederiksen, John K; Shao, Lina; Bixby, Dale L; Ross, Charles W

    2016-04-01

    Systemic mastocytosis (SM) is characterized by a clonal proliferation of aberrant mast cells within extracutaneous sites. In a subset of SM cases, a second associated hematologic non-mast cell disease (AHNMD) is also present, usually of myeloid origin. Polymerase chain reaction and targeted fluorescence in situ hybridization studies have provided evidence that, in at least some cases, the aberrant mast cells are related clonally to the neoplastic cells of the AHNMD. In this work, a single nucleotide polymorphism microarray (SNP-A) was used to characterize the cytogenetics of the aberrant mast cells from a patient with acute myeloid leukemia and concomitant mast cell leukemia associated with a KIT D816A mutation. The results demonstrate the presence of shared cytogenetic abnormalities between the mast cells and myeloid blasts, as well as additional abnormalities within mast cells (copy-neutral loss of heterozygosity) not detectable by routine karyotypic analysis. To our knowledge, this work represents the first application of SNP-A whole-genome scanning to the detection of shared cytogenetic abnormalities between the two components of a case of SM-AHNMD. The findings provide additional evidence of a frequent clonal link between aberrant mast cells and cells of myeloid AHNMDs, and also highlight the importance of direct sequencing for identifying uncommon activating KIT mutations.

  18. Ochratoxin A induces karyomegaly and cell cycle aberrations in renal tubular cells without relation to induction of oxidative stress responses in rats.

    PubMed

    Taniai, Eriko; Yafune, Atsunori; Nakajima, Masahiro; Hayashi, Shim-Mo; Nakane, Fumiyuki; Itahashi, Megu; Shibutani, Makoto

    2014-01-01

    Ochratoxin A (OTA) is a renal carcinogen that induces karyomegaly in target renal tubular cells of the outer stripe of the outer medulla (OSOM). This study was performed to clarify the relationship between oxidative stress and the karyomegaly-inducing potential involving cell cycle aberration of OTA in the OSOM. Rats were treated with OTA for 28 days in combination with enzymatically modified isoquercitrin (EMIQ) or α-lipoic acid (ALA) as antioxidants. OTA increased the mRNA levels of the antioxidant enzyme-related genes Gpx1, Gpx2, Gstm1 and Nfe2l2, but did not increase the levels of Gsta5, Keap1, Nqo1, Hmox1, Aldh1a1, Por, Prdx1 and Txn1. OTA also did not change the levels of thiobarbituric acid-reactive substances, glutathione disulfide/reduced glutathione, and the immunoreactive tubular cell distribution of nuclear factor erythroid 2-related factor 2 in the OSOM. Co-treatment with EMIQ or ALA did not cause any changes in these parameters. As previously reported, OTA increased cell proliferation activity, apoptosis and immunohistochemical cellular distributions of molecules suggestive of induction of DNA damage and cell cycle aberrations involving spindle checkpoint disruption and cell cycle arrest. However, co-treatment with EMIQ or ALA did not suppress these changes, and ALA co-treatment increased the cell proliferation activity induced by OTA. These results suggest that OTA facilitates cell cycling involving cell cycle aberrations and apoptosis as a basis of the mechanism behind the development of karyomegaly and subsequent carcinogenicity targeting the OSOM, without relation to induction of oxidative stress. On the other hand, ALA may promote the OTA-induced proliferation of carcinogenic target cells.

  19. Overexpression of ankyrin1 promotes pancreatic cancer cell growth

    PubMed Central

    Omura, Noriyuki; Mizuma, Masamichi; MacGregor, Anne; Hong, Seung-Mo; Ayars, Michael; Almario, Jose Alejandro; Borges, Michael; Kanda, Mitsuro; Li, Ang; Vincent, Audrey; Maitra, Anirban; Goggins, Michael

    2016-01-01

    The methylation status of a promoter influences gene expression and aberrant methylation during tumor development has important functional consequences for pancreatic and other cancers. Using methylated CpG island amplification and promoter microarrays, we identified ANK1 as hypomethylated in pancreatic cancers. Expression analysis determined ANK1 as commonly overexpressed in pancreatic cancers relative to normal pancreas. ANK1 was co-expressed with miR-486 in pancreatic cancer cells. Stable knockdown of ANK1 in the pancreatic cancer cell line AsPC1 led to changes in cell morphology, and decreases in colony formation. Stable knockdown of ANK1 also marked reduced the growth of tumors in athymic nude mice. Among patients undergoing pancreaticoduodenectomy, those with pancreatic cancers expressing ANK1 had a poorer prognosis than those without ANK1 expression. These findings indicate a role for ANK1 overexpression in mediating pancreatic cancer tumorigenicity. PMID:27144336

  20. Transcription coupled repair deficiency results in increased chromosomal aberrations and apoptotic death in the UV61 cell line, the Chinese hamster homologue of Cockayne's syndrome B.

    PubMed

    Proietti De Santis, L; Garcia, C L; Balajee, A S; Brea Calvo, G T; Bassi, L; Palitti, F

    2001-03-01

    Transcription coupled repair (TCR), a special sub-pathway of nucleotide excision repair (NER), removes transcription blocking lesions rapidly from the transcribing strand of active genes. In this study, we have evaluated the importance of the TCR pathway in the induction of chromosomal aberrations and apoptosis in isogenic Chinese hamster cell lines, which differ in TCR efficiency. AA8 is the parental cell line, which is proficient in the genome overall repair of UV-C radiation induced 6-4 photoproducts (6-4 PP) and the repair of cyclobutane pyrimidine dimer (CPD) from the transcribing strand of active genes. UV61 cells (hamster homologue of human Cockayne's syndrome (CS) group B cells) originally isolated from AA8, exhibit proficient repair of 6-4 PP but are deficient in CPD removal by the TCR pathway. Upon UV-C irradiation of cells in G1-phase, UV61 showed a dramatic increase in apoptotic response as compared to AA8 cells. Abolition of TCR by treatment with alpha-amanitin (an inhibitor of RNA polymerase II) in AA8 cells also resulted in an elevated apoptotic response like that observed in UV61 cells treated with UV alone. This suggests that the lack of TCR is largely responsible for increased apoptotic response in UV61 cells. Furthermore, the chromosomal aberrations and sister chromatid exchange (SCE) induced by UV were also found to be higher in UV61 cells than in TCR proficient AA8 cells. This study shows that the increased chromosomal aberrations and apoptotic death in UV61 cells is due to their inability to remove CPD from the transcribing strand of active genes and suggests a protective role for TCR in the prevention of both chromosomal aberrations and apoptosis induced by DNA damage. Furthermore, flow cytometry analysis and time-course appearance of apoptotic cells suggest that the conversion of UV-DNA damage into chromosomal aberrations precedes and determines the apoptotic process. PMID:11182543

  1. Centrosome aberrations in human mammary epithelial cells driven by cooperative interactions between p16INK4a deficiency and telomere-dependent genotoxic stress

    PubMed Central

    Domínguez, Daniel; Feijoo, Purificación; Bernal, Aina; Ercilla, Amaia; Agell, Neus; Genescà, Anna; Tusell, Laura

    2015-01-01

    Virtually all human cancers display chromosome instability (CIN), a condition in which chromosomes are gained or lost at a high rate. CIN occurs early in cancer development where it may undermine the advance of the neoplastic disease. With the aim of establishing the mechanisms underlying CIN in cancer, we investigated possible links between telomere-dysfunction and centrosome defects, which were seen to coincide in early in breast carcinogenesis using human mammary epithelial cells (HMECs). In this study, we show that TP53 proficient vHMECs cells develop centrosome aberrations when telomere-dysfunction genotoxic stress is produced in the presence of a defective p16INK4a setting and in parallel with an activation of the DNA damage checkpoint response. These aberrations consist of the accumulation of centrosomes in polyploid vHMECs, plus centriole overduplication in both diploid and polyploid cells, thus reflecting that distinct mechanisms underlie the generation of centrosome aberrations in vHMECs. Transduction of vHMEC with hTERT, which rescued the telomere dysfunction phenotype and consequently reduced DNA damage checkpoint activation, led to a progressive reduction of centrosome aberrations with cell culture, both in diploid and in polyploid vHMECs. Radiation-induced DNA damage also raised centrosome aberrations in vHMEC-hTERT. Collectively, our results, using vHMECs define a model where p16INK4a deficiency along with short dysfunctional telomeres cooperatively engenders centrosome abnormalities before p53 function is compromised. PMID:26318587

  2. Chromosome aberrations in workers exposed to arsenic.

    PubMed

    Beckman, G; Beckman, L; Nordenson, I

    1977-08-01

    The occurrence of chromosome aberrations was studied in short-term cultured lymphocytes from nine workers exposed to arsenic at the Rönnskär smeltery in northern Sweden. In the smelter workers, 87 aberrations were found in 819 mitoses. The number of aberrations varied individually from 0 to 25 aberrations per 100 cells. In a control material 13 aberrations were found in 1012 mitoses. The frequency of chromosome aberrations was significantly increased among the smelter workers, but due to the simultaneous exposure to other agents the effect of arsenic per se can not be assessed with certainty.

  3. Biphasic Effects of Nitric Oxide Radicals on Radiation-Induced Lethality and Chromosome Aberrations in Human Lung Cancer Cells Carrying Different p53 Gene Status

    SciTech Connect

    Su Xiaoming; Takahashi, Akihisa; Guo Guozhen; Mori, Eiichiro; Okamoto, Noritomo; Ohnishi, Ken; Iwasaki, Toshiyasu; Ohnishi, Takeo

    2010-06-01

    Purpose: The aim of this study was to clarify the effects of nitric oxide (NO) on radiation-induced cell killing and chromosome aberrations in two human lung cancer cell lines with a different p53 gene status. Methods and Materials: We used wild-type (wt) p53 and mutated (m) p53 cell lines that were derived from the human lung cancer H1299 cell line, which is p53 null. The wtp53 and mp53 cell lines were generated by transfection of the appropriate p53 constructs into the parental cells. Cells were pretreated with different concentrations of isosorbide dinitrate (ISDN) (an NO donor) and/or 2-(4-Carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (c-PTIO) (an NO scavenger) and then exposed to X-rays. Cell survival, apoptosis, and chromosome aberrations were scored by use of a colony-forming assay, Hoechst 33342 staining assay and TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP [deoxyuridine triphosphate] nick end labeling) assay, and chromosomal banding techniques, respectively. Results: In wtp53 cells the induction of radioresistance and the inhibition of apoptosis and chromosome aberrations were observed in the presence of ISDN at low 2- to 10-{mu}mol/L concentrations before X-irradiation. The addition of c-PTIO and ISDN into the culture medium 6 h before irradiation almost completely suppressed these effects. However, at high concentrations of ISDN (100-500 {mu}mol/L), clear evidence of radiosensitization, enhancement of apoptosis, and chromosome aberrations was detected. However, these phenomena were not observed in mp53 cells at either concentration range with ISDN. Conclusions: These results indicate that low and high concentrations of NO radicals can choreograph inverse radiosensitivity, apoptosis, and chromosome aberrations in human lung cancer cells and that NO radicals can affect the fate of wtp53 cells.

  4. Benzene-Induced Aberrant miRNA Expression Profile in Hematopoietic Progenitor Cells in C57BL/6 Mice.

    PubMed

    Wei, Haiyan; Zhang, Juan; Tan, Kehong; Sun, Rongli; Yin, Lihong; Pu, Yuepu

    2015-11-12

    Benzene is a common environmental pollutant that causes hematological alterations. MicroRNAs (miRNAs) may play a role in benzene-induced hematotoxicity. In this study, C57BL/6 mice showed significant hematotoxicity after exposure to 150 mg/kg benzene for 4 weeks. Benzene exposure decreased not only the number of cells in peripheral blood but also hematopoietic progenitor cells in the bone marrow. Meanwhile, RNA from Lin(-) cells sorted from the bone marrow was applied to aberrant miRNA expression profile using Illumina sequencing. We found that 5 miRNAs were overexpressed and 45 miRNAs were downregulated in the benzene exposure group. Sequencing results were confirmed through qRT-PCR. Furthermore, we also identified five miRNAs which significantly altered in Lin(-)c-Kit⁺ cells obtained from benzene-exposed mice, including mmu-miR-34a-5p; mmu-miR-342-3p; mmu-miR-100-5p; mmu-miR-181a-5p; and mmu-miR-196b-5p. In summary, we successfully established a classical animal model to induce significant hematotoxicity by benzene injection. Benzene exposure may cause severe hematotoxicity not only to blood cells in peripheral circulation but also to hematopoietic cells in bone marrow. Benzene exposure also alters miRNA expression in hematopoietic progenitor cells. This study suggests that benzene induces alteration in hematopoiesis and hematopoiesis-associated miRNAs.

  5. Relationship of chromosomal damage induced by caffeine to growth temperature and ATP level in proliferating cells.

    PubMed

    Hernández, P; Mingo, R; González-Fernández, A; López-Sáez, J F

    1986-10-01

    Caffeine is known to induce chromosomal aberrations in proliferating cells when they are incubated during G2 and mitotic prophase. In the present paper, this caffeine effect has been analyzed in Allium cepa root meristems growing at different culture temperatures under steady-state kinetics. Caffeine (1-10 mM) induces chromosomal aberrations in a dose-dependent manner, and the treatment efficiency correlates linearly with the square of caffeine concentration. The efficiency of caffeine incubations, within the range 5-25 degrees C during equivalent cycle time periods has also been studied. It has been found that the lower the culture temperature, the higher the level of chromosomal aberrations. Moreover, at different temperatures, the level of chromosomal aberrations is a simple function of caffeine concentration and the ATP level. Therefore, the efficiency of caffeine treatment appears to be determined by some interaction between caffeine concentration and cellular ATP level. Our present results demonstrate that the influence of growth temperature on the chromosome-breaking effect of caffeine can be, at least partially, explained by the ATP levels during the incubation periods. In short, under different kinetics of plant cell proliferation, the ATP level, and/or something correlating with it, could explain the efficiency of caffeine in inducing chromosomal aberrations: the lower the ATP level, the higher the caffeine efficiency.

  6. Interphase Molecular Cytogenetic Detection Rates of Chronic Lymphocytic Leukemia-Specific Aberrations Are Higher in Cultivated Cells Than in Blood or Bone Marrow Smears.

    PubMed

    Alhourani, Eyad; Aroutiounian, Rouben; Harutyunyan, Tigran; Glaser, Anita; Schlie, Cordula; Pohle, Beate; Liehr, Thomas

    2016-08-01

    Banding cytogenetics is still the gold standard in many fields of leukemia diagnostics. However, in chronic lymphocytic leukemia (CLL), GTG-banding results are hampered by a low mitotic rate of the corresponding malignant lymphatic cells. Thus, interphase fluorescence in situ hybridization (iFISH) for the detection of specific cytogenetic aberrations is done nowadays as a supplement to or even instead of banding cytogenetics in many diagnostic laboratories. These iFISH studies can be performed on native blood or bone marrow smears or in nuclei after cultivation and stimulation by a suitable mitogen. As there are only few comparative studies with partially conflicting results for the detection rates of aberrations in cultivated and native cells, this question was studied in 38 CLL cases with known aberrations in 11q22.2, 11q22.3, 12, 13q14.3, 14q32.33, 17p13.1, or 18q21.32. The obtained results implicate that iFISH directly applied on smears is in general less efficient for the detection of CLL-specific genetic abnormalities than for cultivated cells. This also shows that applied cell culture conditions are well suited for malignant CLL cells. Thus, to detect malignant aberrant cells in CLL, cell cultivation and cytogenetic workup should be performed and the obtained material should be subjected to banding cytogenetics and iFISH. PMID:27315825

  7. Space Radiation Effects on Human Cells: Modeling DNA Breakage, DNA Damage Foci Distribution, Chromosomal Aberrations and Tissue Effects

    NASA Technical Reports Server (NTRS)

    Ponomarev, A. L.; Huff, J. L.; Cucinotta, F. A.

    2011-01-01

    Future long-tem space travel will face challenges from radiation concerns as the space environment poses health risk to humans in space from radiations with high biological efficiency and adverse post-flight long-term effects. Solar particles events may dramatically affect the crew performance, while Galactic Cosmic Rays will induce a chronic exposure to high-linear-energy-transfer (LET) particles. These types of radiation, not present on the ground level, can increase the probability of a fatal cancer later in astronaut life. No feasible shielding is possible from radiation in space, especially for the heavy ion component, as suggested solutions will require a dramatic increase in the mass of the mission. Our research group focuses on fundamental research and strategic analysis leading to better shielding design and to better understanding of the biological mechanisms of radiation damage. We present our recent effort to model DNA damage and tissue damage using computational models based on the physics of heavy ion radiation, DNA structure and DNA damage and repair in human cells. Our particular area of expertise include the clustered DNA damage from high-LET radiation, the visualization of DSBs (DNA double strand breaks) via DNA damage foci, image analysis and the statistics of the foci for different experimental situations, chromosomal aberration formation through DSB misrepair, the kinetics of DSB repair leading to a model-derived spectrum of chromosomal aberrations, and, finally, the simulation of human tissue and the pattern of apoptotic cell damage. This compendium of theoretical and experimental data sheds light on the complex nature of radiation interacting with human DNA, cells and tissues, which can lead to mutagenesis and carcinogenesis later in human life after the space mission.

  8. Peripheral T-cell lymphomas of follicular helper T-cell type frequently display an aberrant CD3(-/dim)CD4(+) population by flow cytometry: an important clue to the diagnosis of a Hodgkin lymphoma mimic.

    PubMed

    Alikhan, Mir; Song, Joo Y; Sohani, Aliyah R; Moroch, Julien; Plonquet, Anne; Duffield, Amy S; Borowitz, Michael J; Jiang, Liuyan; Bueso-Ramos, Carlos; Inamdar, Kedar; Menon, Madhu P; Gurbuxani, Sandeep; Chan, Ernest; Smith, Sonali M; Nicolae, Alina; Jaffe, Elaine S; Gaulard, Philippe; Venkataraman, Girish

    2016-10-01

    Nodal follicular helper T-cell-derived lymphoproliferations (specifically the less common peripheral T-cell lymphomas of follicular type) exhibit a spectrum of histologic features that may mimic reactive hyperplasia or Hodgkin lymphoma. Even though angioimmunoblastic T-cell lymphoma and peripheral T-cell lymphoma of follicular type share a common biologic origin from follicular helper T-cells and their morphology has been well characterized, flow cytometry of peripheral T-cell lymphomas of follicular type has not been widely discussed as a tool for identifying this reactive hyperplasia/Hodgkin lymphoma mimic. We identified 10 peripheral T-cell lymphomas of follicular type with available flow cytometry data from five different institutions, including two cases with peripheral blood evaluation. For comparison, we examined flow cytometry data for 8 classical Hodgkin lymphomas (including 1 lymphocyte-rich classical Hodgkin lymphoma), 15 nodular lymphocyte predominant Hodgkin lymphomas, 15 angioimmunoblastic T-cell lymphomas, and 26 reactive nodes. Lymph node histology and flow cytometry data were reviewed, specifically for the presence of a CD3(-/dim)CD4(+) aberrant T-cell population (described in angioimmunoblastic T-cell lymphomas), besides other T-cell aberrancies. Nine of 10 (90%) peripheral T-cell lymphomas of follicular type showed a CD3(-/dim)CD4(+) T-cell population constituting 29.3% (range 7.9-62%) of all lymphocytes. Five of 10 (50%) had nodular lymphocyte predominant Hodgkin lymphoma or lymphocyte-rich classical Hodgkin lymphoma-like morphology with scattered Hodgkin-like cells that expressed CD20, CD30, CD15, and MUM1. Three cases had a nodular growth pattern and three others exhibited a perifollicular growth pattern without Hodgkin-like cells. Epstein-Barr virus was positive in 1 of 10 cases (10%). PCR analysis showed clonal T-cell receptor gamma gene rearrangement in all 10 peripheral T-cell lymphomas of follicular type. By flow cytometry, 11 of 15 (73

  9. ERα propelled aberrant global DNA hypermethylation by activating the DNMT1 gene to enhance anticancer drug resistance in human breast cancer cells

    PubMed Central

    Lv, Jinghuan; Ding, Haijian; Zhang, Xin A.; Shao, Lipei; Yang, Nan; Cheng, He; Sun, Luan; Zhu, Dongliang; Yang, Yin; Li, Andi; Han, Xiao; Sun, Yujie

    2016-01-01

    Drug-induced aberrant DNA methylation is the first identified epigenetic marker involved in chemotherapy resistance. Understanding how the aberrant DNA methylation is acquired would impact cancer treatment in theory and practice. In this study we systematically investigated whether and how ERα propelled aberrant global DNA hypermethylation in the context of breast cancer drug resistance. Our data demonstrated that anticancer drug paclitaxel (PTX) augmented ERα binding to the DNMT1 and DNMT3b promoters to activate DNMT1 and DNMT3b genes, enhancing the PTX resistance of breast cancer cells. In support of these observations, estrogen enhanced multi-drug resistance of breast cancer cells by up-regulation of DNMT1 and DNMT3b genes. Nevertheless, the aberrant global DNA hypermethylation was dominantly induced by ERα-activated-DNMT1, since DNMT1 over-expression significantly increased global DNA methylation and DNMT1 knockdown reversed the ERα-induced global DNA methylation. Altering DNMT3b expression had no detectable effect on global DNA methylation. Consistently, the expression level of DNMT1 was positively correlated with ERα in 78 breast cancer tissue samples shown by our immunohistochemistry (IHC) analysis and negatively correlated with relapse-free survival (RFS) and distance metastasis-free survival (DMFS) of ERα-positive breast cancer patients. This study provides a new perspective for understanding the mechanism underlying drug-resistance-facilitating aberrant DNA methylation in breast cancer and other estrogen dependent tumors. PMID:26980709

  10. ZNF217 confers resistance to the pro-apoptotic signals of paclitaxel and aberrant expression of Aurora-A in breast cancer cells

    PubMed Central

    2010-01-01

    Background ZNF217 is a candidate oncogene located at 20q13, a chromosomal region frequently amplified in breast cancers. The precise mechanisms involved in ZNF217 pro-survival function are currently unknown, and utmost importance is given to deciphering the role of ZNF217 in cancer therapy response. Results We provide evidence that stable overexpression of ZNF217 in MDA-MB-231 breast cancer cells conferred resistance to paclitaxel, stimulated cell proliferation in vitro associated with aberrant expression of several cyclins, and increased tumor growth in mouse xenograft models. Conversely, siRNA-mediated silencing of ZNF217 expression in MCF7 breast cancer cells, which possess high endogenous levels of ZNF217, led to decreased cell proliferation and increased sensitivity to paclitaxel. The paclitaxel resistance developed by ZNF217-overexpressing MDA-MB-231 cells was not mediated by the ABCB1/PgP transporter. However, ZNF217 was able to counteract the apoptotic signals mediated by paclitaxel as a consequence of alterations in the intrinsic apoptotic pathway through constitutive deregulation of the balance of Bcl-2 family proteins. Interestingly, ZNF217 expression levels were correlated with the oncogenic kinase Aurora-A expression levels, as ZNF217 overexpression led to increased expression of the Aurora-A protein, whereas ZNF217 silencing was associated with low Aurora-A expression levels. We showed that a potent Aurora-A kinase inhibitor was able to reverse paclitaxel resistance in the ZNF217-overexpressing cells. Conclusion Altogether, these data suggest that ZNF217 might play an important role in breast neoplastic progression and chemoresistance, and that Aurora-A might be involved in ZNF217-mediated effects. PMID:21059223

  11. Conformational Characterization of Aberrant Disulfide-linked HIV-1 gp120 Dimers Secreted from Overexpressing Cells

    PubMed Central

    Finzi, Andrés; Pacheco, Beatriz; Zeng, Xin; Do Kwon, Young; Kwong, Peter D.; Sodroski, Joseph

    2010-01-01

    The envelope (Env) glycoproteins of human immunodeficiency virus (HIV-1) mediate viral entry and are also the primary target of neutralizing antibodies. The gp160 envelope glycoprotein precursor undergoes proteolytic cleavage in the Golgi complex to produce the gp120 exterior glycoprotein and the gp41 transmembrane glycoprotein, which remain associated non-covalently in the trimeric Env complex. Monomeric soluble gp120 has been used extensively to investigate conformational states, structure, antigenicity and immunogenicity of the HIV-1 Env glycoproteins. Expression of gp120 alone (without gp41) leads to the accumulation not only of monomeric gp120 but also an aberrant dimeric form. The gp120 dimers were sensitive to reducing agents. The formation of gp120 dimers was disrupted by a single amino acid change in the inner domain, and was reduced by removal of the V1/V2 variable loops or the N and C termini. Epitopes on the gp120 inner domain and the chemokine receptor-binding surface were altered or occluded by gp120 dimerization. Awareness of the existence and properties of gp120 dimers should assist interpretation of studies of this key viral protein. PMID:20471426

  12. Induction and repair of chromosome aberrations in scid cells measured by premature chromosome condensation

    SciTech Connect

    Evans, J.W.; Kirchgessner, C.U.; Brown, J.M.; X.F. Liu

    1996-01-01

    Severe combined immunodeficient (scid) murine cells, which are defective in both repair of DNA double-strand breaks and V(D)J recombination, are deficient in DNA-dependent protein kinase (DNA-PK), a protein which forms an activated complex with the DNA end-binding Ku proteins (p80 and p70) upon association with damaged DNA. Xrs 5 cells are deficient in the Ku p80 protein and also fail to form an active DNA-PK repair complex. Since both scid and xrs cells are defective in the same protein complex, we compared the kinetics of chromosome repair in scid cells to results published previously for xrs 5 cells. C.B-17 cells, scid cells and scid cells complemented with a single human chromosome 8 were irradiated with 6 Gy and allowed to repair from 0-24 h before fusion to HeLa cells for chromosome condensation. Breaks and dicentrics were visualized by fluorescence in situ hybridization. All cells had the same initial amount of chromosome damage, but scid cells had a slower rate of rejoining, more unrejoined breaks and more dicentrics than C.B-17 and scid cells with human chromosome 8. The scid cells appear to respond differently than xrs 5 cells, despite both cells lacking an essential component of the same DNA repair complex. 40 refs., 6 figs., 3 tabs.

  13. Multicopy Fzf1 (Sul1) Suppresses the Sulfite Sensitivity but Not the Glucose Derepression or Aberrant Cell Morphology of a Grr1 Mutant of Saccharomyces Cerevisiae

    PubMed Central

    Avram, D.; Bakalinsky, A. T.

    1996-01-01

    An ssu2 mutation in Sacccharomyces cerevisiae, previously shown to cause sulfite sensitivity, was found to be allelic to GRR1, a gene previously implicated in glucose repression. The suppressor rgt1, which suppresses the growth defects of grr1 strains on glucose, did not fully suppress the sensitivity on glucose or nonglucose carbon sources, indicating that it is not strictly linked to a defect in glucose metabolism. Because the Cln1 protein was previously shown to be elevated in grr1 mutants, the effect of CLN1 overexpression on sulfite sensitivity was investigated. Overexpression in GRR1 cells resulted in sulfite sensitivity, suggesting a connection between CLN1 and sulfite metabolism. Multicopy FZF1, a putative transcription factor, was found to suppress the sulfite sensitive phenotype of grr1 strains, but not the glucose derepression or aberrant cell morphology. Multicopy FZF1 was also found to suppress the sensitivity of a number of other unrelated sulfite-sensitive mutants, but not that of ssu1 or met20, implying that FZF1 may act through Ssu1p and Met20p. Disruption of FZF1 resulted in sulfite sensitivity when the construct was introduced in single copy at the FZF1 locus in a GRR1 strain, providing evidence that FZF1 is involved in sulfite metabolism. PMID:8889516

  14. Chromosome aberration and micronucleus frequencies in Allium cepa cells exposed to petroleum polluted water--a case study.

    PubMed

    Leme, Daniela Morais; Marin-Morales, Maria Aparecida

    2008-01-31

    In the present study, we applied Chromosome Aberration (CA) and Micronucleus (MN) tests to Allium cepa root cells, in order to evaluate the water quality of Guaecá river. This river, located in the city of São Sebastião, SP, Brazil, had been affected by an oil pipeline leak. Chemical analyses of Total Petroleum Hydrocarbons (TPHs) and Polycyclic Aromatic Hydrocarbons (PAHs) were also carried out in water samples, collected in July 2005 (dry season) and February 2006 (rainy season) in 4 different river sites. The largest CA and MN incidence in the meristematic cells of A. cepa was observed after exposure to water sample collected during the dry season, at the spring of the river, where the oil leak has arisen. The F(1) cells from roots exposed to such sample (non-merismatic region) were also analyzed for the incidence of MN, showing a larger frequency of irregularities, indicating a possible development of CA into MN. Lastly, our study reveals a direct correlation between water chemical analyses (contamination by TPHs and PAHs) and both genotoxic and mutagenic effects observed in exposed A. cepa cells. PMID:18068420

  15. mTOR Controls Ovarian Follicle Growth by Regulating Granulosa Cell Proliferation

    PubMed Central

    Yu, James; Yaba, Aylin; Kasiman, Corinna; Thomson, Travis; Johnson, Joshua

    2011-01-01

    We have shown that inhibition of mTOR in granulosa cells and ovarian follicles results in compromised granulosa proliferation and reduced follicle growth. Further analysis here using spontaneously immortalized rat granulosa cells has revealed that mTOR pathway activity is enhanced during M-phase of the cell cycle. mTOR specific phosphorylation of p70S6 kinase and 4E-BP, and expression of Raptor are all enhanced during M-phase. The predominant effect of mTOR inhibition by the specific inhibitor Rapamycin (RAP) was a dose-responsive arrest in the G1 cell cycle stage. The fraction of granulosa cells that continued to divide in the presence of RAP exhibited a dose-dependent increase in aberrant mitotic figures known as anaphase bridges. Strikingly, estradiol consistently decreased the incidence of aberrant mitotic figures. In mice treated with RAP, the mitotic index was reduced compared to controls, and a similar increase in aberrant mitotic events was noted. RAP injected during a superovulation regime resulted in a dose-dependent reduction in the numbers of eggs ovulated. Implications for the real-time regulation of follicle growth and dominance, including the consequences of increased numbers of aneuploid granulosa cells, are discussed. PMID:21750711

  16. Parabolic growth patterns in 96-well plate cell growth experiments.

    PubMed

    Faessel, H M; Levasseur, L M; Slocum, H K; Greco, W R

    1999-05-01

    In preparing for the routine use of the ubiquitous in vitro cell growth inhibition assay for the study of anticancer agents, we characterized the statistical properties of the assay and found some surprising results. Parabolic well-to-well cell growth patterns were discovered, which could profoundly affect the results of routine growth inhibition studies of anticancer and other agents. Four human ovarian cell lines, A2780/WT, A2780/DX5, A2780/DX5B, and A121, and one human ileocecal adenocarcinoma cell line, HCT-8, were seeded into plastic 96-well plates with a 12-channel pipette, without drugs, and grown from 1-5 d. The wells were washed with a plate washer, cells stained with sulforhodamine B (SRB), and dye absorbance measured with a plate reader. Variance models were fit to the data from replicates to determine the nature of the heteroscedastic error structure. Exponential growth models were fit to data to estimate doubling times for each cell line. Polynomial models were fit to data from 10-plate stacks of 96-well plates to explore nonuniformity of cell growth in wells in different regions of the stacks. Each separate step in the assay was examined for precision, patterns, and underlying causes of variation. Differential evaporation of water from wells is likely a major, but not exclusive, contributor to the systematic well-to-well cell growth patterns. Because the fundamental underlying causes of the parabolic growth patterns were not conclusively found, a randomization step for the growth assay was developed.

  17. Measurement of adherent cell mass and growth

    PubMed Central

    Park, Kidong; Millet, Larry J.; Kim, Namjung; Li, Huan; Jin, Xiaozhong; Popescu, Gabriel; Aluru, N. R.; Hsia, K. Jimmy; Bashir, Rashid

    2010-01-01

    The characterization of physical properties of cells such as their mass and stiffness has been of great interest and can have profound implications in cell biology, tissue engineering, cancer, and disease research. For example, the direct dependence of cell growth rate on cell mass for individual adherent human cells can elucidate the mechanisms underlying cell cycle progression. Here we develop an array of micro-electro-mechanical systems (MEMS) resonant mass sensors that can be used to directly measure the biophysical properties, mass, and growth rate of single adherent cells. Unlike conventional cantilever mass sensors, our sensors retain a uniform mass sensitivity over the cell attachment surface. By measuring the frequency shift of the mass sensors with growing (soft) cells and fixed (stiff) cells, and through analytical modeling, we derive the Young’s modulus of the unfixed cell and unravel the dependence of the cell mass measurement on cell stiffness. Finally, we grew individual cells on the mass sensors and measured their mass for 50+ hours. Our results demonstrate that adherent human colon epithelial cells have increased growth rates with a larger cell mass, and the average growth rate increases linearly with the cell mass, at 3.25%/hr. Our sensitive mass sensors with a position-independent mass sensitivity can be coupled with microscopy for simultaneous monitoring of cell growth and status, and provide an ideal method to study cell growth, cell cycle progression, differentiation, and apoptosis. PMID:21068372

  18. QUANTITATION OF ABERRANT INTERLOCUS T-CELL RECEPTOR REARRANGEMENTS IN MOUSE THYMOCYTES AND THE EFFECT OF THE HERBICIDE 2,4- DICHLOROPHENOXYACETIC ACID

    EPA Science Inventory

    Quantitation of aberrant interlocus T-cell receptor rearrangements in mouse thymocytes and the effect of the herbicide 2,4- Dichlorophenoxyacetic acid

    Small studies in human populations have suggested a correlation between the frequency of errors in antigen receptor gene a...

  19. Diesel exhaust particles induce aberrant alveolar epithelial directed cell movement by disruption of polarity mechanisms.

    PubMed

    LaGier, Adriana J; Manzo, Nicholas D; Dye, Janice A

    2013-01-01

    Disruption of the respiratory epithelium contributes to the progression of a variety of respiratory diseases that are aggravated by exposure to air pollutants, specifically traffic-based pollutants such as diesel exhaust particles (DEP). Recognizing that lung repair following injury requires efficient and directed alveolar epithelial cell migration, this study's goal was to understand the mechanisms underlying alveolar epithelial cells response to DEP, particularly when exposure is accompanied with comorbid lung injury. Separate mechanistic steps of directed migration were investigated in confluent murine LA-4 cells exposed to noncytotoxic concentrations (0-100 μg/cm(2)) of either automobile-emitted diesel exhaust particles (DEP(A)) or carbon black (CB) particles. A scratch wound model ascertained how DEP(A) exposure affected directional cell migration and BCECF ratio fluorimetry-monitored intracellular pH (pHi). Cells were immunostained with giantin to assess cell polarity, and with paxillin to assess focal cell adhesions. Cells were immunoblotted for ezrin/radixin/moesin (ERM) to assess cytoskeletal anchoring. Data demonstrate herein that exposure of LA-4 cells to DEP(A) (but not CB) resulted in delayed directional cell migration, impaired de-adhesion of the trailing edge cell processes, disrupted regulation of pHi, and altered Golgi polarity of leading edge cells, along with modified focal adhesions and reduced ERM levels, indicative of decreased cytoskeletal anchoring. The ability of DEP(A) to disrupt directed cell migration at multiple levels suggests that signaling pathways such as ERM/Rho are critical for transduction of ion transport signals into cytoskeletal arrangement responses. These results provide insights into the mechanisms by which chronic exposure to traffic-based emissions may result in decrements in lung capacity. PMID:23294296

  20. Trichostatin A specifically improves the aberrant expression of transcription factor genes in embryos produced by somatic cell nuclear transfer.

    PubMed

    Inoue, Kimiko; Oikawa, Mami; Kamimura, Satoshi; Ogonuki, Narumi; Nakamura, Toshinobu; Nakano, Toru; Abe, Kuniya; Ogura, Atsuo

    2015-01-01

    Although mammalian cloning by somatic cell nuclear transfer (SCNT) has been established in various species, the low developmental efficiency has hampered its practical applications. Treatment of SCNT-derived embryos with histone deacetylase (HDAC) inhibitors can improve their development, but the underlying mechanism is still unclear. To address this question, we analysed gene expression profiles of SCNT-derived 2-cell mouse embryos treated with trichostatin A (TSA), a potent HDAC inhibitor that is best used for mouse cloning. Unexpectedly, TSA had no effect on the numbers of aberrantly expressed genes or the overall gene expression pattern in the embryos. However, in-depth investigation by gene ontology and functional analyses revealed that TSA treatment specifically improved the expression of a small subset of genes encoding transcription factors and their regulatory factors, suggesting their positive involvement in de novo RNA synthesis. Indeed, introduction of one of such transcription factors, Spi-C, into the embryos at least partially mimicked the TSA-induced improvement in embryonic development by activating gene networks associated with transcriptional regulation. Thus, the effects of TSA treatment on embryonic gene expression did not seem to be stochastic, but more specific than expected, targeting genes that direct development and trigger zygotic genome activation at the 2-cell stage. PMID:25974394

  1. Chromosome aberration and sister chromatid exchange tests in Chinese hamster ovary cells in vitro III: Results with 27 chemicals

    SciTech Connect

    Gulati, D.K. ); Witt, K.; Anderson, B.; Zeiger, E.; Shelby, M.D. )

    1989-01-01

    Twenty-seven chemicals previously tested in rodent carcinogenicity assays were tested for induction of chromosomal aberrations (ABS) and sister chromatid exchanges (SCE) in Chinese hamster ovary (CHO) cells as part of a larger analysis of the correlation between results of in vitro genetic toxicity assays and carcinogenicity bioassays. Chemicals were tested up to toxic doses with and without exogenous metabolic activation. Seventeen of the chemicals tested were carcinogens; only two of these were negative for both ABS and SCE. Of the eight noncarcinogens tested, four were negative for both endpoints and four gave a positive response for at least one endpoint. Of the remaining two chemicals, one, diallylphthalate, gave an equivocal response in the bioassay and a positive response in these CHO cell cytogenetics tests. The other chemical, 2,4-toluene diisocyanate, was tested for carcinogenicity as a mixture with the 2,6-isomer; the mixture was carinogenic, but the cytogenetic test results for the 2,4-isomer were negative. Experiments with unsynchronized CHO cells demonstrated that mean SCE frequency increased with increasing culture time, and this may have been a factor in the positive results obtained for five chemicals in the SCE test under conditions of delayed harvest.

  2. Enhanced oxidative stress and aberrant mitochondrial biogenesis in human neuroblastoma SH-SY5Y cells during methamphetamine induced apoptosis

    SciTech Connect

    Wu, C.-W.; Ping, Y.-H.; Yen, J.-C.; Chang, C.-Y.; Wang, S.-F.; Yeh, C.-L.; Chi, C.-W.; Lee, H.-C. . E-mail: hclee2@ym.edu.tw

    2007-05-01

    Methamphetamine (METH) is an abused drug that may cause psychiatric and neurotoxic damage, including degeneration of monoaminergic terminals and apoptosis of non-monoaminergic cells in Brain. The cellular and molecular mechanisms underlying these METH-induced neurotoxic effects remain to be clarified. In this study, we performed a time course assessment to investigate the effects of METH on intracellular oxidative stress and mitochondrial alterations in a human dopaminergic neuroblastoma SH-SY5Y cell line. We characterized that METH induces a temporal sequence of several cellular events including, firstly, a decrease in mitochondrial membrane potential within 1 h of the METH treatment, secondly, an extensive decline in mitochondrial membrane potential and increase in the level of reactive oxygen species (ROS) after 8 h of the treatment, thirdly, an increase in mitochondrial mass after the drug treatment for 24 h, and finally, a decrease in mtDNA copy number and mitochondrial proteins per mitochondrion as well as the occurrence of apoptosis after 48 h of the treatment. Importantly, vitamin E attenuated the METH-induced increases in intracellular ROS level and mitochondrial mass, and prevented METH-induced cell death. Our observations suggest that enhanced oxidative stress and aberrant mitochondrial biogenesis may play critical roles in METH-induced neurotoxic effects.

  3. Interplay between cell growth and cell cycle in plants.

    PubMed

    Sablowski, Robert; Carnier Dornelas, Marcelo

    2014-06-01

    The growth of organs and whole plants depends on both cell growth and cell-cycle progression, but the interaction between both processes is poorly understood. In plants, the balance between growth and cell-cycle progression requires coordinated regulation of four different processes: macromolecular synthesis (cytoplasmic growth), turgor-driven cell-wall extension, mitotic cycle, and endocycle. Potential feedbacks between these processes include a cell-size checkpoint operating before DNA synthesis and a link between DNA contents and maximum cell size. In addition, key intercellular signals and growth regulatory genes appear to target at the same time cell-cycle and cell-growth functions. For example, auxin, gibberellin, and brassinosteroid all have parallel links to cell-cycle progression (through S-phase Cyclin D-CDK and the anaphase-promoting complex) and cell-wall functions (through cell-wall extensibility or microtubule dynamics). Another intercellular signal mediated by microtubule dynamics is the mechanical stress caused by growth of interconnected cells. Superimposed on developmental controls, sugar signalling through the TOR pathway has recently emerged as a central control point linking cytoplasmic growth, cell-cycle and cell-wall functions. Recent progress in quantitative imaging and computational modelling will facilitate analysis of the multiple interconnections between plant cell growth and cell cycle and ultimately will be required for the predictive manipulation of plant growth.

  4. Aberrant Notch signaling in glioblastoma stem cells contributes to tumor recurrence and invasion.

    PubMed

    Yu, Jian-Bo; Jiang, Hao; Zhan, Ren-Ya

    2016-08-01

    Upregulation of the Notch signaling pathway in cancer stem cells and side population (SP) cells has a major role in maintenance, self-renewal and chemoresistance. The present study isolated a cancer stem cell-like SP accounting for 4.1% of a glioblastoma cell population using a Hoechst 33342 dye exclusion assay. In this glioblastoma SP, the expression of of Notch1 signaling proteins Notch1 intracellular domain and Hes‑1 was markedly upregulated. Furthermore, knockdown of Notch1 by RNA interference significantly diminished the neurosphere formation ability, self‑renewal and chemoresistance of the SP cells. In addition, the expression of the stem‑cell surface genes Oct‑4, Sox2 and Nanog in SP cells was significantly reduced and the sensitivity to the SP cells to chemotherapeutics was enhanced following Notch1 knockdown. In conclusion, the results of the present study suggested that upregulation of Notch1 is involved in the chemotherapy resistance and tumor recurrence of glioblastoma. Hence, the development of novel anti‑cancer drugs targeting the Notch1 signaling pathway may be a promising strategy for curing glioblastoma. PMID:27315154

  5. CCR7 Deficiency Exacerbates Injury in Acute Nephritis Due to Aberrant Localization of Regulatory T Cells

    PubMed Central

    Eller, Kathrin; Weber, Tobias; Pruenster, Monika; Wolf, Anna M.; Mayer, Gert

    2010-01-01

    The homing of dendritic cells and T cells to secondary lymphoid organs requires chemokine receptor 7 (CCR7) expression on these cells. T cells mediate the pathogenesis of experimental accelerated nephrotoxic serum nephritis (NTS), including its suppression by regulatory T cells (Tregs), but the contribution of CCR7 to this disease is unknown. Here, we compared the development of NTS in CCR7-knockout (KO) and wild-type (WT) mice. Compared with WT mice, CCR7KO mice developed more severe disease with significantly more inflammatory cells infiltrating the kidney. These cells included FoxP3+ Tregs, which were virtually absent from WT kidneys. The adoptive transfer of WT Tregs into CCR7KO mice at the time of immunization protected the recipients from disease; these cells homed to secondary lymphoid organs but not to kidneys. Conversely, adoptive transfer of CCR7KO Tregs into WT mice did not inhibit development of NTS. These data suggest that NTS can develop without CCR7 expression, but Treg-mediated disease suppression, which seems to occur in secondary lymphoid organs, requires CCR7. PMID:19917782

  6. High-level DNA amplifications are common genetic aberrations in B-cell neoplasms.

    PubMed Central

    Werner, C. A.; Döhner, H.; Joos, S.; Trümper, L. H.; Baudis, M.; Barth, T. F.; Ott, G.; Möller, P.; Lichter, P.; Bentz, M.

    1997-01-01

    Gene amplification is one of the molecular mechanisms resulting in the up-regulation of gene expression. In non-Hodgkin's lymphomas, such gene amplifications have been identified rarely. Using comparative genomic hybridization, a technique that has proven to be very sensitive for the detection of high-level DNA amplifications, we analyzed 108 cases of B-cell neoplasms (42 chronic B-cell leukemias, 5 mantle cell lymphomas, and 61 aggressive B-cell lymphomas). Twenty-four high-level amplifications were identified in 13% of the patients and mapped to 15 different genomic regions. Regions most frequently amplified were bands Xq26-28, 2p23-24, and 2p14-16 as well as 18q21 (three times each). Amplification of several proto-oncogenes and a cell cycle control gene (N-MYC (two cases), BCL2, CCND2, and GLI) located within the amplified regions was demonstrated by Southern blot analysis or fluorescence in situ hybridization to interphase nuclei of tumor cells. These data demonstrate that gene amplifications in B-cell neoplasms are much more frequent than previously assumed. The identification of highly amplified DNA regions and genes included in the amplicons provides important information for further analyses of genetic events involved in lymphomagenesis. Images Figure 2 Figure 3 PMID:9250147

  7. Analysis of aberrant methylation in DNA repair genes during malignant transformation of human bronchial epithelial cells induced by cadmium.

    PubMed

    Zhou, Zhi-heng; Lei, Yi-xiong; Wang, Cai-xia

    2012-02-01

    Cadmium (Cd) and its compounds are well-known human carcinogens, but the mechanisms underlying the carcinogenesis are not entirely understood yet. Aberrant methylation was investigated in order to obtain insight into the DNA repair-related epigenetic mechanisms underlying CdCl(2)-induced malignant transformation of human bronchial epithelial cells (16HBE). Gene expression and DNA methylation were assessed in untreated control cells; 5th, 15th, and 35th passage of CdCl2-treated cells and tumorigenic cells (TCs) from nude mice by using high-performance liquid chromatography, real-time PCR, Western blot analysis, and methylation-specific PCR assay. During Cd-induced malignant transformation, global DNA methylation progressively increased and was associated with the overexpression of the DNA methyltransferase genes DNMT1 and DNMT3a but not DNMT3b. Expression of both the messenger RNA and proteins of the DNA repair genes (hMSH2, ERCC1, XRCC1, and hOGG1) progressively reduced and DNA damage increased with Cd-induced transformation. The promoter regions of hMSH2, ERCC1, XRCC1, and hOGG1 were heavily methylated in the 35th passage transformed cells and the TCs. The DNA demethylating agent 5-aza-2'-deoxycytidine could reverse the Cd-induced global DNA hypermethylation, DNMT hyperactivity, and the silencing of hMSH2, ERCC1, XRCC1, and hOGG1 in a time-dependent manner. The results indicate that DNMT1 and DNMT3a overexpression can result in global DNA hypermethylation and silencing of the hMSH2, ERCC1, XRCC1, and hOGG1 genes. They may partly explain the epigenetic mechanisms underlying the carcinogenesis due to Cd.

  8. Insufficient role of cell proliferation in aberrant DNA methylation induction and involvement of specific types of inflammation.

    PubMed

    Hur, Keun; Niwa, Tohru; Toyoda, Takeshi; Tsukamoto, Tetsuya; Tatematsu, Masae; Yang, Han-Kwang; Ushijima, Toshikazu

    2011-01-01

    Chronic inflammation is deeply involved in induction of aberrant DNA methylation, but it is unclear whether any type of persistent inflammation can induce methylation and how induction of cell proliferation is involved. In this study, Mongolian gerbils were treated with five kinds of inflammation inducers [Helicobacter pylori with cytotoxin-associated gene A (CagA), H.pylori without CagA, Helicobacter felis, 50% ethanol (EtOH) and saturated sodium chloride (NaCl) solution]. Two control groups were treated with a mutagenic carcinogen that induces little inflammation (20 p.p.m. of N-methyl-N-nitrosourea) and without any treatment. After 20 weeks, chronic inflammation with lymphocyte and macrophage infiltration was prominent in the three Helicobacter groups, whereas neutrophil infiltration was mainly observed in the EtOH and NaCl groups. Methylation levels of eight CpG islands significantly increased only in the three Helicobacter groups. By Ki-67 staining, cell proliferation was most strongly induced in the NaCl group, demonstrating that induction of cell proliferation is not sufficient for methylation induction. Among the inflammation-related genes, Il1b, Nos2 and Tnf showed increased expression specifically in the three Helicobacter groups. In human gastric mucosae infected by H.pylori, NOS2 and TNF were also increased. These data showed that inflammation due to infection of the three Helicobacter strains has a strong potential to induce methylation, regardless of their CagA statuses, and increased cell proliferation was not sufficient for methylation induction. It was suggested that specific types of inflammation characterized by expression of specific inflammation-related genes, along with increased cell proliferation, are necessary for methylation induction.

  9. Aberrant epigenetic regulation in clear cell sarcoma of the kidney featuring distinct DNA hypermethylation and EZH2 overexpression

    PubMed Central

    Jansson, Caroline; O'Sullivan, Maureen J.; Mengelbier, Linda Holmquist; Gisselsson, David

    2016-01-01

    The global methylation profile and the mutational status of 633 specific epigenetic regulators were analyzed in the pediatric tumor clear cell sarcoma of the kidney (CCSK). Methylation array analyses of 30 CCSKs revealed CCSK tumor DNA to be globally hypermethylated compared to Wilms tumor, normal fetal kidney, and adult kidney. The aberrant methylation pattern of CCSKs was associated with activation of genes involved in embryonic processes and with silencing of genes linked to normal kidney function. No epigenetic regulator was recurrently mutated in our cohort, but a mutation in the key epigenetic regulator EZH2 was discovered in one case. EZH2 mRNA was significantly higher in CCSK compared to Wilms tumor and normal kidney, and the EZH2 protein was strongly expressed in more than 90 % of CCSK tumor cells in 9/9 tumors analyzed. This was in striking contrast to the lack of EZH2 protein expression in Wilms tumor stromal elements, indicating that EZH2 could be explored further as a diagnostic marker and a potential drug target for CCSK. PMID:26848979

  10. Cigarette smoke extract induces aberrant cytochrome-c oxidase subunit II methylation and apoptosis in human umbilical vascular endothelial cells.

    PubMed

    Yang, Min; Chen, Ping; Peng, Hong; Zhang, Hongliang; Chen, Yan; Cai, Shan; Lu, Qianjin; Guan, Chaxiang

    2015-03-01

    Cigarette smoke-induced apoptosis of vascular endothelial cells contributes to the pathogenesis of chronic obstructive pulmonary disease. However, the mechanisms responsible for endothelial apoptosis remain poorly understood. We conducted an in vitro study to investigate whether DNA methylation is involved in smoking-induced endothelial apoptosis. Human umbilical vascular endothelial cells (HUVECs) were exposed to cigarette smoke extract (CSE) at a range of concentrations (0-10%). HUVECs were also incubated with a demethylating reagent, 5-aza-2'-deoxycytidinem (AZA), with and without CSE. Apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay and flow cytometry using annexin V-FITC/propidium iodide staining. We found that CSE treatment significantly increased HUVEC apoptosis in a dose- and time-dependent manner. Quantitative real-time RT-PCR and immunoblot revealed that CSE treatment decreased cytochrome-c oxidase subunit II (COX II) mRNA and protein levels and decreased COX activity. Methylation-specific PCR and direct bisulfite sequencing revealed positive COX II gene methylation. AZA administration partly increased mRNA and protein expressions of COX II, and COX activity decreased by CSE and attenuated the toxic effects of CSE. Our results showed that CSE induced aberrant COX II methylation and apoptosis in HUVECs. PMID:25500741

  11. Subgroup J avian leukosis virus infection of chicken dendritic cells induces apoptosis via the aberrant expression of microRNAs.

    PubMed

    Liu, Di; Dai, Manman; Zhang, Xu; Cao, Weisheng; Liao, Ming

    2016-02-01

    Subgroup J avian leukosis virus (ALV-J) is an oncogenic retrovirus that causes immunosuppression and enhances susceptibility to secondary infection. The innate immune system is the first line of defense in preventing bacterial and viral infections, and dendritic cells (DCs) play important roles in innate immunity. Because bone marrow is an organ that is susceptible to ALV-J, the virus may influence the generation of bone marrow-derived DCs. In this study, DCs cultured in vitro were used to investigate the effects of ALV infection. The results revealed that ALV-J could infect these cells during the early stages of differentiation, and infection of DCs with ALV-J resulted in apoptosis. miRNA sequencing data of uninfected and infected DCs revealed 122 differentially expressed miRNAs, with 115 demonstrating upregulation after ALV-J infection and the other 7 showing significant downregulation. The miRNAs that exhibited the highest levels of upregulation may suppress nutrient processing and metabolic function. These results indicated that ALV-J infection of chicken DCs could induce apoptosis via aberrant microRNA expression. These results provide a solid foundation for the further study of epigenetic influences on ALV-J-induced immunosuppression.

  12. Influence of retinol on carcinogen-induced sister chromatid exchangers and chromosome aberrations in V79 cells

    SciTech Connect

    Qin, S.; Batt, T.; Huang, C.C.

    1985-01-01

    The influence of retinol (Rol) on sister chromatid exchangers (SCE) in V79 cells induced by six indirect and two direct carcinogens, and on chromosome aberration (CA) in V79 cells induced by four indirect carcinogens were studied. The indirect carcinogens used were aflatoxin B/sub 1/ (AFB), cyclophosphamide (CPP), benzo(a)anthracene (BA), benzo(a)pyrene (BP), 9,10-dimethyl-1,2-benz(a)anthracene (DMBA), and 3-methylcholanthrene (MCA). The two direct carcinogens were ethyl methane sulfonate (EMS) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Rol effectively inhibited SCE and CA induced by AFB and CPP in a dose-dependent manner, but it had no effect on SCE induced by BA, BP, DMBA, MCA, EMS, and MNNG. To the contrary, Rol had an enhancing effect on CA induced by BP and DMBA. The possibility that Rol exerts its anticarcinogenic effects by inhibiting certain forms of the cytochrome P-450 isoenzymes required for activation of precarcinogens, such as AFB and CPP but not those enzymes required by BA, BP, DMBA, and MCA, is discussed.

  13. Aberrant immunoglobulin class switch recombination and switch translocations in activated B cell–like diffuse large B cell lymphoma

    PubMed Central

    Lenz, Georg; Nagel, Inga; Siebert, Reiner; Roschke, Anna V.; Sanger, Warren; Wright, George W.; Dave, Sandeep S.; Tan, Bruce; Zhao, Hong; Rosenwald, Andreas; Muller-Hermelink, Hans Konrad; Gascoyne, Randy D.; Campo, Elias; Jaffe, Elaine S.; Smeland, Erlend B.; Fisher, Richard I.; Kuehl, W. Michael; Chan, Wing C.; Staudt, Louis M.

    2007-01-01

    To elucidate the mechanisms underlying chromosomal translocations in diffuse large B cell lymphoma (DLBCL), we investigated the nature and extent of immunoglobulin class switch recombination (CSR) in these tumors. We used Southern blotting to detect legitimate and illegitimate CSR events in tumor samples of the activated B cell–like (ABC), germinal center B cell–like (GCB), and primary mediastinal B cell lymphoma (PMBL) subgroups of DLBCL. The frequency of legitimate CSR was lower in ABC DLBCL than in GCB DLBCL and PMBL. In contrast, ABC DLBCL had a higher frequency of internal deletions within the switch μ (Sμ) region compared with GCB DLBCL and PMBL. ABC DLBCLs also had frequent deletions within Sγ and other illegitimate switch recombinations. Sequence analysis revealed ongoing Sμ deletions within ABC DLBCL tumor clones, which were accompanied by ongoing duplications and activation-induced cytidine deaminase–dependent somatic mutations. Unexpectedly, short fragments derived from multiple chromosomes were interspersed within Sμ in one case. These findings suggest that ABC DLBCLs have abnormalities in the regulation of CSR that could predispose to chromosomal translocations. Accordingly, aberrant switch recombination was responsible for translocations in ABC DLBCLs involving BCL6, MYC, and a novel translocation partner, SPIB. PMID:17353367

  14. Radiation-induced chromosome aberrations in ataxia telangiectasia cells: high frequency of deletions and misrejoining detected by fluorescence in situ hybridization

    NASA Technical Reports Server (NTRS)

    Kawata, Tetsuya; Ito, Hisao; George, Kerry; Wu, Honglu; Uno, Takashi; Isobe, Kouichi; Cucinotta, Francis A.

    2003-01-01

    The mechanisms underlying the hyper-radiosensitivity of AT cells were investigated by analyzing chromosome aberrations in the G(2) and M phases of the cell cycle using a combination of chemically induced premature chromosome condensation (PCC) and fluorescence in situ hybridization (FISH) with chromosome painting probes. Confluent cultures of normal fibroblast cells (AG1522) and fibroblast cells derived from an individual with AT (GM02052) were exposed to gamma rays and allowed to repair at 37 degrees C for 24 h. At doses that resulted in 10% survival, GM02052 cells were approximately five times more sensitive to gamma rays than AG1522 cells. For a given dose, GM02052 cells contained a much higher frequency of deletions and misrejoining than AG1522 cells. For both cell types, a good correlation was found between the percentage of aberrant cells and cell survival. The average number of color junctions, which represent the frequency of chromosome misrejoining, was also found to correlate well with survival. However, in a similar surviving population of GM02052 and AG1522 cells, induced by 1 Gy and 6 Gy, respectively, AG1522 cells contained four times more color junctions and half as many deletions as GM02052 cells. These results indicate that both repair deficiency and misrepair may be involved in the hyper-radiosensitivity of AT cells.

  15. Aberrant Apoptotic Response of Colorectal Cancer Cells to Novel Nucleoside Analogues

    PubMed Central

    Harmse, Leonie; Dahan-Farkas, Nurit; Panayides, Jenny-Lee; van Otterlo, Willem; Penny, Clement

    2015-01-01

    Despite the increased understanding of colorectal cancer and the introduction of targeted drug therapy, the metastatic phase of the disease remains refractory to treatment. Since the deregulation of normal apoptosis contributes to the pathogenesis of colorectal cancer, novel nucleoside analogues were synthesized here and evaluated for their ability to induce apoptosis and cause cell death in two colorectal adeno-carcinoma cell lines, Caco-2 and HT-29. Three novel nucleoside analogues assessed here showed cytotoxic activity, as measured by the MTT assay against both cell lines: the IC50 values ranged between 3 and 37 μM, with Caco-2 cells being more sensitive than HT-29 cells. Compared to camptothecin, the positive control, the nucleoside analogues were significantly less toxic to normal unstimulated leukocytes (p>0.05). Moreover, the nucleosides were able to induce apoptosis as measured by an increase in caspase 8 and caspase 3 activity above that of the control. This was additionally supported by data derived from Annexin V-FITC assays. Despite marginal changes to the mitochondrial membrane potential, all three nucleosides caused a significant increase in cytosolic cytochrome c (p>0.05), with a corresponding decrease in mitochondrial cytochrome c. Morphological analysis of both cell lines showed the rapid appearance of vacuoles following exposure to two of the nucleosides, while a third caused cellular detachment, delayed cytoplasmic vacuolisation and nuclear abnormalities. Preliminary investigations, using the autophagic indicator monodansylcadaverine and chloroquine as positive control, showed that two of the nucleosides induced the formation of autophagic vacuoles. In summary, the novel nucleoside analogues showed selective cytotoxicity towards both cancer cell lines and are effective initiators of an unusual apoptotic response, demonstrating their potential to serve as structural scaffolds for more potent analogues. PMID:26390405

  16. Aberrant expression of the neuronal transcription factor FOXP2 in neoplastic plasma cells.

    PubMed

    Campbell, Andrew J; Lyne, Linden; Brown, Philip J; Launchbury, Rosalind J; Bignone, Paola; Chi, Jianxiang; Roncador, Giovanna; Lawrie, Charles H; Gatter, Kevin C; Kusec, Rajko; Banham, Alison H

    2010-04-01

    FOXP2 mutation causes a severe inherited speech and language defect, while the related transcription factors FOXP1, FOXP3 and FOXP4 are implicated in cancer. FOXP2 mRNA and protein expression were characterised in normal human tissues, haematological cell lines and multiple myeloma (MM) patients' samples. FOXP2 mRNA and protein were absent in mononuclear cells from different anatomical sites, lineages and stages of differentiation. However, FOXP2 mRNA and protein was detected in several lymphoma (8/20) and all MM-derived cell lines (n = 4). FOXP2 mRNA was expressed in bone marrow samples from 96% of MM patients (24/25), 66.7% of patients with the pre-neoplastic plasma cell proliferation monoclonal gammopathy of undetermined significance (MGUS) (6/9), but not in reactive plasma cells. The frequency of FOXP2 protein expression in CD138(+) plasma cells was significantly higher in MGUS (P = 0.0005; mean 46.4%) and MM patients (P < or = 0.0001; mean 57.3%) than in reactive marrows (mean 2.5%). FOXP2 (>10% nuclear positivity) was detectable in 90.2% of MM (55/61) and 90.9% of MGUS (10/11) patients, showing more frequent expression than CD56 and labelling 75% of CD56-negative MM (9/12). FOXP2 represents the first transcription factor whose expression consistently differentiates normal and abnormal plasma cells and FOXP2 target genes are implicated in MM pathogenesis.

  17. Basal cell carcinoma and the carcinogenic role of aberrant Hedgehog signaling.

    PubMed

    Saran, Anna

    2010-06-01

    Basal cell carcinoma (BCC) is the most frequent cancer in the white population and its incidence appears to be increasing worldwide. While the majority of BCCs arise sporadically, many cases are attributable to basal cell nevus syndrome, or Gorlin syndrome, an autosomal dominantly inherited disorder characterized by the occurrence of multiple BCCs and by extracutaneous tumors. Genetic studies on patients with basal cell nevus syndrome indicate deregulation of the Hedgehog (Hh) pathway in epidermal keratinocytes as the primary event in the pathogenesis of BCC. This article summarizes the recent progress in understanding Hh-dependent BCC tumorigenesis, as well as evidence for deregulation of other molecular pathways, primarily the Wnt developmental pathway. Understanding the molecular genetics of BCC development has provided new opportunities for molecular therapy of this cancer by targeting Hh and other signaling pathways. PMID:20528237

  18. Aberrant expression of proPTPRN2 in cancer cells confers resistance to apoptosis

    PubMed Central

    Sorokin, Alexey V.; Nair, Binoj C.; Wei, Yongkun; Aziz, Kathryn E.; Evdokimova, Valentina; Hung, Mien-Chie; Chen, Junjie

    2015-01-01

    The protein tyrosine phosphatase receptor PTPRN2 is expressed predominantly in endocrine and neuronal cells where it functions in exocytosis. We found that its immature isoform proPTPRN2 is overexpressed in various cancers including breast cancer. High proPTPRN2 expression was associated strongly with lymph node-positive breast cancer and poor clinical outcome. Loss of proPTPRN2 in breast cancer cells promoted apoptosis and blocked tumor formation in mice, while enforced expression of proPTPRN2 in non-transformed human mammary epithelial cells exerted a converse effect. Mechanistic investigations suggested that ProPTPRN2 elicited these effects through direct interaction with TRAF2, a hub scaffold protein for multiple kinase cascades including ones that activate NF-kB. Overall our results suggest PTPRN2 as a novel candidate biomarker and therapeutic target in breast cancer. PMID:25877877

  19. Painting analysis of chromosome aberrations induced by energetic heavy ions in human cells

    NASA Astrophysics Data System (ADS)

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

    Energetic heavy ions pose a great health risk to astronauts in extended ISS and future exploration missions High-LET heavy ions are particularly effective in causing various biological effects including cell inactivation genetic mutations and cancer induction Most of these biological endpoints are closely related to chromosomal damage which can be utilized as a biomarker for radiation insults Over the years we have studied chromosomal damage in human fibroblast epithelia and lymphocyte cells exposed in vitro to energetic charged particles generated at several accelerator facilities in the world Various fluorescence in situ hybridization painting techniques have been used to identify from only the telomere region of the chromosome to every chromosome in a human cell We will summarize the results of the investigations and discuss the unique radiation signatures and biomarkers for space radiation exposure

  20. FGFR1, 2 and 3 protein overexpression and molecular aberrations of FGFR3 in early stage non‐small cell lung cancer

    PubMed Central

    Mittempergher, Lorenza; Willems, Stefan M; Bosma, Astrid J; Peters, Dennis DGC; van der Noort, Vincent; Japenga, Eva J; Peeters, Ton; Koole, Koos; Šuštić, Tonći; Blaauwgeers, JL; van Noesel, Carel J; Bernards, René

    2016-01-01

    Abstract This study aimed to determine protein expression levels of fibroblast growth factor receptors (FGFR) 1, 2 and 3 in early stage non‐small cell lung cancer (NSCLC). Additionally, a screen to define the frequency of FGFR3‐TACC3 translocation and FGFR3 amplification was performed. Archived tissues from 653 NSCLC samples (adenocarcinoma (AC), squamous cell carcinoma (SCC) and large cell carcinoma (LCC)) were analysed with immunohistochemistry (IHC) for expression of FGFR1, 2 and 3. Expression levels of FGFR1, 2 and 3 were correlated with clinicopathological features. The presence of FGFR3‐TACC3 translocation was detected by RT‐PCR and FGFR3 amplification was detected by fluorescence in situ hybridization. FGFR1, 2 and 3 proteins were highly expressed in 64 (10.6%), 76 (12.9%) and 20 (3.3%) NSCLC tumour samples, respectively. Protein expression of FGFR1 was significantly related to worse overall survival in NSCLC. Furthermore, FGFR1 protein expression was associated with light smoking and histological subtype (AC), FGFR2 protein expression with female gender, younger age, histological subtype (AC) and lower tumour stage, and FGFR3 protein was significantly overexpressed in tumours of older patients and SCC histology. The FGFR3‐TACC3 fusion was detected in 3.0% (6/200) of NSCLC samples and the FGFR3 gene was amplified in 4.7% of IHC positive NSCLC samples (2/43). FGFR1, 2 and 3 proteins are expressed in a high number of early stage NSCLC and FGFR1 protein expression may serve as a prognostic biomarker. Recurrent translocations and amplifications in FGFR3 can be found in NSCLC. This study shows that FGFR family members are frequently aberrant in NSCLC and could be interesting therapeutic targets for the treatment of NSCLC.

  1. M-BAND Analysis of Chromosome Aberration Induced by Fe-Ions in Human Epithelial Cells Cultured in 3-Dimensional Matrices

    NASA Technical Reports Server (NTRS)

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

    2008-01-01

    Energetic heavy ions pose a great health risk to astronauts in extended ISS and future lunar and Mars missions. High-LET heavy ions are particularly effective in causing various biological effects, including cell inactivation, genetic mutations, cataracts and cancer induction. Most of these biological endpoints are closely related to chromosomal damage, which can be utilized as a biomarker for radiation insults. Previously, we had studied low- and high-LET radiation-induced chromosome aberrations in human epithelial cells cultured in 2-dimension (2D) using the multicolor banding fluorescence in situ hybridization (mBAND) technique. However, it has been realized that the biological response to radiation insult in a 2D cellular environment in vitro can differ significantly from the response in 3-dimension (3D) or at the actual tissue level. In this study, we cultured human epithelial cells in 3D to provide a more suitable model for human tissue. Human mammary epithelia cells (CH184B5F5/M10) were grown in Matrigel to form 3D structures, and exposed to Fe-ions at NASA Space Radiation Laboratory (NSRL) at the Brookhaven National Laboratory or 137Cs-gamma radiation source at the University of Texas MD Anderson Cancer Center. After exposure, cells were allowed to repair for 16hr before dissociation and subcultued at low density in 2D. G2 and metaphase chromosomes in the first cell cycle were collected using a chemical-induced premature chromosome condensation (PCC) technique, and chromosome aberrations were analyzed using mBAND technique. With this technique, individually painted chromosomal bands on one chromosome allowed the identification of interchromosomal aberrations (translocation to unpainted chromosomes) and intrachromosomal aberrations (inversions and deletions within a single painted chromosome). Our data indicate a significant difference of the chromosome aberration yield between 2D and 3D cell cultures for gamma exposures, but not for Fe ion exposures

  2. M-BAND analysis of chromosome aberration induced by Fe-ions in human epithelial cells cultured in 3-dimensional matrices

    NASA Astrophysics Data System (ADS)

    Hada, Megumi; Cucinotta, Francis A.; Wu, Honglu

    Energetic heavy ions pose a great health risk to astronauts in extended ISS and future lunar and Mars missions. High-LET heavy ions are particularly effective in causing various biological effects, including cell inactivation, genetic mutations, cataracts and cancer induction. Most of these biological endpoints are closely related to chromosomal damage, which can be utilized as a biomarker for radiation insults. Previously, we had studied lowand high-LET radiationinduced chromosome aberrations in human epithelial cells cultured in 2-dimension (2D) using the multicolor banding fluorescence in situ hybridization (mBAND) technique. However, it has been realized that the biological response to radiation insult in a 2D cellular environment in vitro can differ significantly from the response in 3-dimension (3D) or at the actual tissue level. In this study, we cultured human epithelial cells in 3D to provide a more suitable model for human tissue. Human mammary epithelial cells (CH184B5F5/M10) were grown in Matrigel to form 3D structures, and exposed to Fe-ions at NASA Space Radiation Laboratory (NSRL) at the Brookhaven National Laboratory or 137 Cs-gamma radiation source at the University of Texas MD Anderson Cancer Center. After exposure, cells were allowed to repair for 16hr before dissociation and subcultured at low density in 2D. G2 and metaphase chromosomes in the first cell cycle were collected using a chemical-induced premature chromosome condensation (PCC) technique, and chromosome aberrations were analyzed using mBAND technique. With this technique, individually painted chromosomal bands on one chromosome allowed the identification of interchromosomal aberrations (translocation to unpainted chromosomes) and intrachromosomal aberrations (inversions and deletions within a single painted chromosome). Our data indicate a significant difference of the chromosome aberration yield between 2D and 3D cell cultures for gamma exposures, but not for Fe ion exposures

  3. Comparative genomic hybridization analysis of newly established retinoblastoma cell lines of adherent growth compared with Y79 of nonadherent growth.

    PubMed

    Kim, Jeong Hun; Kim, Jin Hyoung; Yu, Young Suk; Kim, Dong Hun; Kim, Yong Kyu; Kim, Kyu-Won

    2008-08-01

    Retinoblastoma (RB) shows cytogenetic aberrations involving genes other than RB gene located on 13q14. We analyzed genomic aberration in newly established RB cell lines SNUOT-RB1 and SNUOT-RB4 of adherent growth and Y79 cell line of nonadherent growth by microarray comparative genomic hybridization. SNUOT-RB1 showed 44 significant copy number changes (gain in 11 and loss in 33, P<0.0005). SNUOT-RB4 showed 42 significant copy number changes (gain in 8 and loss in 34, P<0.0005). Y79 cell line had the greatest gain of 19.65-fold in the locus of MYCN gene 2p24.1, whereas SNUOT-RB1 and SNUOT-RB4 showed no significant gain. SNUOT-RB1 and SNUOT-RB4 gained chromosomal copy numbers commonly in chromosome 11, especially in locus 11q13, which is responsible for cancer-related genes such as CCND1, MEN1, and FGF3. Losses of copy numbers occurred in chromosomes 3, 9, 10, 11, 16, and 17. In summary, SNUOT-RB1 and SNUOT-RB4 represented similar pattern in gain and loss of chromosomal copy number changes, while different from Y79. The loss of CYLD gene of tumor suppressor gene, 16q12-q13, was only on locus of common involvement in 3 cell lines. PMID:18799932

  4. Mucinous spindle and tubular renal cell carcinoma: analysis of chromosomal aberration pattern of low-grade, high-grade, and overlapping morphologic variant with papillary renal cell carcinoma.

    PubMed

    Peckova, Kvetoslava; Martinek, Petr; Sperga, Maris; Montiel, Delia Perez; Daum, Ondrej; Rotterova, Pavla; Kalusová, Kristýna; Hora, Milan; Pivovarcikova, Kristýna; Rychly, Boris; Vranic, Semir; Davidson, Whitney; Vodicka, Josef; Dubová, Magdaléna; Michal, Michal; Hes, Ondrej

    2015-08-01

    The chromosomal numerical aberration pattern in mucinous tubular and spindle renal cell carcinoma (MTSRCC) is referred to as variable with frequent gains and losses. The objectives of this study are to map the spectrum of chromosomal aberrations (extent and location) in a large cohort of the cases and relate these findings to the morphologic variants of MTSRCC. Fifty-four MTSRCCs with uniform morphologic pattern were selected (of 133 MTSRCCs available in our registry) and divided into 3 groups: classic low-grade MTSRCC (Fuhrman nucleolar International Society of Urological Pathology grade 2), high-grade MTSRCC (grade 3), and overlapping MTSRCC with papillary renal cell carcinoma (RCC) morphology. Array comparative genomic hybridization analysis was applied to 16 cases in which DNA was well preserved. Four analyzable classic low-grade MTSRCCs showed multiple losses affecting chromosomes 1, 4, 8, 9, 14, 15, and 22. No chromosomal gains were found. Four analyzable cases of MTSRCC showing overlapping morphology with PRCC displayed a more variable pattern including normal chromosomal status; losses of chromosomes 1, 6, 8, 9, 14, 15, and 22; and gains of 3, 7, 16, and 17. The group of 4 high-grade MTSRCCs exhibited a more uniform chromosomal aberration pattern with losses of chromosomes 1, 4, 6, 8, 9, 13, 14, 15, and 22 and without any gains detected. (1) MTSRCC, both low-grade and high-grade, shows chromosomal losses (including 1, 4, 6, 8, 9, 13, 14, 15, and 22) in all analyzable cases; this seems to be the most frequent chromosomal numerical aberration in this type of RCC. (2) Cases with overlapping morphologic features (MTSRCC and PRCC) showed a more variable pattern with multiple losses and gains, including gains of chromosomes 7 and 17 (2 cases). This result is in line with previously published morphologic and immunohistochemical studies that describe the broad morphologic spectrum of MTSRCC, with changes resembling papillary RCC. (3) The diagnosis of MTSRCC in

  5. U87MG Decoded: The Genomic Sequence of a Cytogenetically Aberrant Human Cancer Cell Line

    PubMed Central

    Eskin, Ascia; Lee, Hane; Merriman, Barry; Nelson, Stanley F.

    2010-01-01

    U87MG is a commonly studied grade IV glioma cell line that has been analyzed in at least 1,700 publications over four decades. In order to comprehensively characterize the genome of this cell line and to serve as a model of broad cancer genome sequencing, we have generated greater than 30× genomic sequence coverage using a novel 50-base mate paired strategy with a 1.4kb mean insert library. A total of 1,014,984,286 mate-end and 120,691,623 single-end two-base encoded reads were generated from five slides. All data were aligned using a custom designed tool called BFAST, allowing optimal color space read alignment and accurate identification of DNA variants. The aligned sequence reads and mate-pair information identified 35 interchromosomal translocation events, 1,315 structural variations (>100 bp), 191,743 small (<21 bp) insertions and deletions (indels), and 2,384,470 single nucleotide variations (SNVs). Among these observations, the known homozygous mutation in PTEN was robustly identified, and genes involved in cell adhesion were overrepresented in the mutated gene list. Data were compared to 219,187 heterozygous single nucleotide polymorphisms assayed by Illumina 1M Duo genotyping array to assess accuracy: 93.83% of all SNPs were reliably detected at filtering thresholds that yield greater than 99.99% sequence accuracy. Protein coding sequences were disrupted predominantly in this cancer cell line due to small indels, large deletions, and translocations. In total, 512 genes were homozygously mutated, including 154 by SNVs, 178 by small indels, 145 by large microdeletions, and 35 by interchromosomal translocations to reveal a highly mutated cell line genome. Of the small homozygously mutated variants, 8 SNVs and 99 indels were novel events not present in dbSNP. These data demonstrate that routine generation of broad cancer genome sequence is possible outside of genome centers. The sequence analysis of U87MG provides an unparalleled level of mutational

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

    PubMed Central

    Atwood, Craig S.; Bowen, Richard L.

    2016-01-01

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

  7. VMP1-deficient Chlamydomonas exhibits severely aberrant cell morphology and disrupted cytokinesis

    PubMed Central

    2014-01-01

    Background The versatile Vacuole Membrane Protein 1 (VMP1) has been previously investigated in six species. It has been shown to be essential in macroautophagy, where it takes part in autophagy initiation. In addition, VMP1 has been implicated in organellar biogenesis; endo-, exo- and phagocytosis, and protein secretion; apoptosis; and cell adhesion. These roles underly its proven involvement in pancreatitis, diabetes and cancer in humans. Results In this study we analyzed a VMP1 homologue from the green alga Chlamydomonas reinhardtii. CrVMP1 knockdown lines showed severe phenotypes, mainly affecting cell division as well as the morphology of cells and organelles. We also provide several pieces of evidence for its involvement in macroautophagy. Conclusion Our study adds a novel role to VMP1's repertoire, namely the regulation of cytokinesis. Though the directness of the observed effects and the mechanisms underlying them remain to be defined, the protein's involvement in macroautophagy in Chlamydomonas, as found by us, suggests that CrVMP1 shares molecular characteristics with its animal and protist counterparts. PMID:24885763

  8. Epitaxial silicon growth for solar cells

    NASA Technical Reports Server (NTRS)

    Daiello, R. V.; Robinson, P. H.; Richman, D.

    1978-01-01

    Growth and fabrication procedures for the baseline solar cells are described along with measured cell parameters, and the results. Reproducibility of these results was established and the direction to be taken for higher efficiency is identified.

  9. Role of mast cells in tumor growth.

    PubMed

    Conti, Pio; Castellani, Maria L; Kempuraj, Durasamy; Salini, Vincenzo; Vecchiet, Jacopo; Tetè, Stefano; Mastrangelo, Filiberto; Perrella, Alessandro; De Lutiis, Maria Anna; Tagen, Michael; Theoharides, Theoharis C

    2007-01-01

    The growth of malignant tumors is determined in large part by the proliferative capacity of the tumor cells. Clinical observations and animal experiments have established that tumor cells elicit immune responses. Histopathologic studies show that many tumors are surrounded by mononuclear cell and mast cell infiltrates. Mast cells are ubiquitous in the body and are critical for allergic reactions. Increasing evidence indicates that mast cells secrete proinflammatory cytokines and are involved in neuro-inflammatory processes and cancer. Mast cells accumulate in the stroma surrounding certain tumors, especially mammary adenocarcinoma, and the molecules they secrete can benefit the tumor. However, mast cells can also increase at the site of tumor growth and participate in tumor rejection. Mast cells may be recruited by tumor-derived chemoattractants and selectively secrete molecules such as growth factors, histamine, heparin, VEGF, and IL-8, as well as proteases that permit the formation of new blood vessels and metastases. Tumor mast cell intersections play regulatory and modulatory roles affecting various aspects of tumor growth. Discovery of these new roles of mast cells further complicates the understanding of tumor growth. This review focuses on the strategic importance of mast cells to the progression of tumors, and proposes a revised immune effector mechanism of mast cell involvement in tumor growth. PMID:18000287

  10. Disruption of Rest Leads to the Early Onset of Cataracts with the Aberrant Terminal Differentiation of Lens Fiber Cells.

    PubMed

    Aoki, Hitomi; Ogino, Hajime; Tomita, Hiroyuki; Hara, Akira; Kunisada, Takahiro

    2016-01-01

    REST (RE1-silencing transcription factor, also called Nrsf) is involved in the maintenance of the undifferentiated state of neuronal stem/progenitor cells in vitro by preventing precocious expression of neuronal genes. REST expression was then decreased in developing neurons to down-regulate neuronal genes which allow their maturation. However, the function of REST during neurogenesis in vivo remains to be elucidated because of the early embryonic lethal phenotype of conventional Rest knockout mice. In order to investigate the role of REST in ocular tissues, we generated and examined the mice evoking genetic ablation to Rest specifically to neural tissues including ocular tissue. We used a Sox1-Cre allele to excise the floxed Rest gene in the early neural tissues including the lens and retinal primordia. The resulting Rest conditional knockout (CKO) and co cntrol mice were used in comparative morphological, histological, and gene expression analyses. Rest CKO mice had an abnormal lens morphology after birth. The proliferation of lens epithelial cells was likely to be slightly reduced, and vacuoles formed without a visible increase in apoptotic cells. Although the aberrant expression of late onset cataract marker proteins was not detected, the expression of Notch signaling-related genes including a previously identified REST-target gene was up-regulated around birth, and this was followed by the down-regulated expression of lens fiber regulators such as c-Maf and Prox1. Rest CKO induces a unique cataract phenotype just after birth. Augmented Notch signaling and the down-regulated expression of lens fiber regulator genes may be responsible for this phenotype. Our results highlight the significance of REST function in lens fiber formation, which is necessary for maintaining an intact lens structure. PMID:27631609

  11. Disruption of Rest Leads to the Early Onset of Cataracts with the Aberrant Terminal Differentiation of Lens Fiber Cells

    PubMed Central

    Aoki, Hitomi; Ogino, Hajime; Tomita, Hiroyuki; Hara, Akira; Kunisada, Takahiro

    2016-01-01

    REST (RE1-silencing transcription factor, also called Nrsf) is involved in the maintenance of the undifferentiated state of neuronal stem/progenitor cells in vitro by preventing precocious expression of neuronal genes. REST expression was then decreased in developing neurons to down-regulate neuronal genes which allow their maturation. However, the function of REST during neurogenesis in vivo remains to be elucidated because of the early embryonic lethal phenotype of conventional Rest knockout mice. In order to investigate the role of REST in ocular tissues, we generated and examined the mice evoking genetic ablation to Rest specifically to neural tissues including ocular tissue. We used a Sox1-Cre allele to excise the floxed Rest gene in the early neural tissues including the lens and retinal primordia. The resulting Rest conditional knockout (CKO) and co cntrol mice were used in comparative morphological, histological, and gene expression analyses. Rest CKO mice had an abnormal lens morphology after birth. The proliferation of lens epithelial cells was likely to be slightly reduced, and vacuoles formed without a visible increase in apoptotic cells. Although the aberrant expression of late onset cataract marker proteins was not detected, the expression of Notch signaling-related genes including a previously identified REST-target gene was up-regulated around birth, and this was followed by the down-regulated expression of lens fiber regulators such as c-Maf and Prox1. Rest CKO induces a unique cataract phenotype just after birth. Augmented Notch signaling and the down-regulated expression of lens fiber regulator genes may be responsible for this phenotype. Our results highlight the significance of REST function in lens fiber formation, which is necessary for maintaining an intact lens structure. PMID:27631609

  12. Phyllanthus emblica Fruit Extract Activates Spindle Assembly Checkpoint, Prevents Mitotic Aberrations and Genomic Instability in Human Colon Epithelial NCM460 Cells

    PubMed Central

    Guo, Xihan; Wang, Xu

    2016-01-01

    The fruit of Phyllanthus emblica Linn. (PE) has been widely consumed as a functional food and folk medicine in Southeast Asia due to its remarkable nutritional and pharmacological effects. Previous research showed PE delays mitotic progress and increases genomic instability (GIN) in human colorectal cancer cells. This study aimed to investigate the similar effects of PE by the biomarkers related to spindle assembly checkpoint (SAC), mitotic aberrations and GIN in human NCM460 normal colon epithelial cells. Cells were treated with PE and harvested differently according to the biomarkers observed. Frequencies of micronuclei (MN), nucleoplasmic bridge (NPB) and nuclear bud (NB) in cytokinesis-block micronucleus assay were used as indicators of GIN. Mitotic aberrations were assessed by the biomarkers of chromosome misalignment, multipolar division, chromosome lagging and chromatin bridge. SAC activity was determined by anaphase-to- metaphase ratio (AMR) and the expression of core SAC gene budding uninhibited by benzimidazoles related 1 (BubR1). Compared with the control, PE-treated cells showed (1) decreased incidences of MN, NPB and NB (p < 0.01); (2) decreased frequencies of all mitotic aberration biomarkers (p < 0.01); and (3) decreased AMR (p < 0.01) and increased BubR1 expression (p < 0.001). The results revealed PE has the potential to protect human normal colon epithelial cells from mitotic and genomic damages partially by enhancing the function of SAC. PMID:27598149

  13. Phyllanthus emblica Fruit Extract Activates Spindle Assembly Checkpoint, Prevents Mitotic Aberrations and Genomic Instability in Human Colon Epithelial NCM460 Cells.

    PubMed

    Guo, Xihan; Wang, Xu

    2016-01-01

    The fruit of Phyllanthus emblica Linn. (PE) has been widely consumed as a functional food and folk medicine in Southeast Asia due to its remarkable nutritional and pharmacological effects. Previous research showed PE delays mitotic progress and increases genomic instability (GIN) in human colorectal cancer cells. This study aimed to investigate the similar effects of PE by the biomarkers related to spindle assembly checkpoint (SAC), mitotic aberrations and GIN in human NCM460 normal colon epithelial cells. Cells were treated with PE and harvested differently according to the biomarkers observed. Frequencies of micronuclei (MN), nucleoplasmic bridge (NPB) and nuclear bud (NB) in cytokinesis-block micronucleus assay were used as indicators of GIN. Mitotic aberrations were assessed by the biomarkers of chromosome misalignment, multipolar division, chromosome lagging and chromatin bridge. SAC activity was determined by anaphase-to- metaphase ratio (AMR) and the expression of core SAC gene budding uninhibited by benzimidazoles related 1 (BubR1). Compared with the control, PE-treated cells showed (1) decreased incidences of MN, NPB and NB (p < 0.01); (2) decreased frequencies of all mitotic aberration biomarkers (p < 0.01); and (3) decreased AMR (p < 0.01) and increased BubR1 expression (p < 0.001). The results revealed PE has the potential to protect human normal colon epithelial cells from mitotic and genomic damages partially by enhancing the function of SAC. PMID:27598149

  14. Aberrant activation-induced cytidine deaminase expression in Philadelphia chromosome-positive B-cell acute lymphoblastic leukemia.

    PubMed

    Shi, Yang; Zhao, Xiaoxian; Durkin, Lisa; Rogers, Heesun Joyce; Hsi, Eric D

    2016-06-01

    Activation-induced cytidine deaminase (AID) is expressed in germinal center B cells and plays a critical role in somatic hypermutation and class-switch recombination of immunoglobulin genes. Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) carries a poor prognosis and is specifically treated with tyrosine kinase inhibitors. Interestingly, AID has been shown to be aberrantly expressed and functional in Ph+ ALL and is thought to contribute to genetic instability. We hypothesized that AID might be detectable in routinely processed bone marrow biopsies by immunohistochemistry (IHC) and assist in identifying Ph+ ALL. We found that AID was expressed in 26 (70%) of 37 cases of Ph+ ALL but only 1 (2.9%) of 38 cases of Ph- ALL cases. There was a significant difference in AID expression between these 2 ALL groups (P < .001, Fisher exact test). The expression of AID was confirmed by RT-PCR (reverse-transcriptase polymerase chain reaction) and correlated with IHC scoring. AID protein is expressed in a large proportion of Ph+ ALL cases at levels detectable by IHC in clinical samples and might be useful to rapidly identify cases likely to have a BCR/ABL1 fusion. PMID:26980048

  15. Assessment of chromosomal aberration in the bone marrow cells of Swiss Albino mice treated by 4-methylimidazole.

    PubMed

    Norizadeh Tazehkand, Mostafa; Topaktas, Mehmet; Yilmaz, Mehmet Bertan

    2016-01-01

    4-Methylimidazole (4-MEI) is formed during the production of certain caramel coloring agents used in many food and drink products. It may also be formed during the cooking, roasting, or other processing of some foods and beverages. So it was unintentionally consumed in worldwide. This study was aimed to investigate the genotoxic and cytotoxic effects of 4-MEI using chromosome aberration (CA) and mitotic index (MI) in Swiss Albino mice. In this research, CA and MI of the mouse bone marrow cells were analyzed after treating the animals with 4-MEI (100, 130 and 160 mg/kg) for 12 h and 24 h treatment times. All data were analyzed using statistical methods. 4-MEI significantly increased the percentage of CAs at all concentrations for 12 h and at highest concentration for 24 h treatment periods. 4-MEI at highest concentration for 12 h and at all concentrations for 24 h decreased the MI in comparison with control. Genotoxic and cytotoxic effects of 4-MEI at 24 h treatment periods were concentration dependent. Consequently, it can be said that 4-MEI have genotoxic and cytotoxic effect in mouse. PMID:26634952

  16. Dietary Ziziphus jujuba Fruit Influence on Aberrant Crypt Formation and Blood Cells in Colitis-Associated Colorectal Cancer in Mice.

    PubMed

    Periasamy, Srinivasan; Liu, Chung-Teng; Wu, Wang-Hung; Chien, Se-Ping; Liu, Ming-Yie

    2015-01-01

    Ziziphus jujuba (ZJ) fruit is rich in bioactive functional components such as polysaccharides, triterpenoid acid, flavonoids and oleamide. It has been commonly used in the treatment of various diseases including diabetes, digestive disorders, diarrhea, skin infections, liver and urinary complaints. However, dietary effects with regard to chemoprevention of colon cancer have not been studied. The present study was performed to evaluate the protective effects of dietary ZJ against colitis-associated colon carcinogenesis in azoxymethane (AOM)-dextran sodium sulphate (DSS)-treated mice. AOM was injected (10 mg/kg b.wt., i.p.) and three cycles of 2% DSS in drinking water for 7 days with 14 days of normal drinking water in-between were administered to induce colitis-associated colon cancer. ZJ fruit was supplemented into feed at levels of 5 and 10%. Dietary ZJ significantly attenuated aberrant crypt foci (ACF) formation and also decreased the progression of hyperplasia to dysplasia. In addition, it significantly reduced circulating white blood cells, lymphocytes, neutrophils, monocytes, eosinophils, basophils and platelets compared to colon cancer mice. We conclude that ZJ supplementation may delay the progression of colon cancer from hyperplasia to dysplasia and ultimately adenocarcinoma and cancer. In addition, it decreased circulating tumor-related leukocytes, main regulators of cancer inflammation. Dietary consumption of ZJ fruit attenuated the formation of ACF and delayed the progression of colon cancer.

  17. Separating strain from composition in unit cell parameter maps obtained from aberration corrected high resolution transmission electron microscopy imaging

    SciTech Connect

    Schulz, T.; Remmele, T.; Korytov, M.; Markurt, T.; Albrecht, M.; Duff, A.; Lymperakis, L.; Neugebauer, J.; Chèze, C.

    2014-01-21

    Based on the evaluation of lattice parameter maps in aberration corrected high resolution transmission electron microscopy images, we propose a simple method that allows quantifying the composition and disorder of a semiconductor alloy at the unit cell scale with high accuracy. This is realized by considering, next to the out-of-plane, also the in-plane lattice parameter component allowing to separate the chemical composition from the strain field. Considering only the out-of-plane lattice parameter component not only yields large deviations from the true local alloy content but also carries the risk of identifying false ordering phenomena like formations of chains or platelets. Our method is demonstrated on image simulations of relaxed supercells, as well as on experimental images of an In{sub 0.20}Ga{sub 0.80}N quantum well. Principally, our approach is applicable to all epitaxially strained compounds in the form of quantum wells, free standing islands, quantum dots, or wires.

  18. Cell Assisted Cell Growth Experiments with Dictyostelium discoideum

    NASA Astrophysics Data System (ADS)

    Bae, Albert; Ip, Wui; Franck, Carl

    2007-03-01

    In eukaryotic cell culture, it is routinely recommended to keep the cells above a minimum cell density to maintain vigorous growth. We are investigating the basis for this prescription by viewing cell growth as a social behavior facilitated by cell-cell communication. Employing Dictyostelium discoideum, we find good evidence for a slow-fast transition in the cell growth rate vs. density in well mixed, 25 ml, cell cultures. We also use low height microfluidic chambers (four orders of magnitude smaller in volume) to find similar behavior even though the system is not well mixed and the cells are confined to substrates. A preliminary measurement at a flow rate that should strongly perturb cell-cell communication by means of diffusing signal molecules suggests that cell communication essential for growth is not accomplished by such means but possibly via direct contacts.

  19. Stochastic Gompertz model of tumour cell growth.

    PubMed

    Lo, C F

    2007-09-21

    In this communication, based upon the deterministic Gompertz law of cell growth, a stochastic model in tumour growth is proposed. This model takes account of both cell fission and mortality too. The corresponding density function of the size of the tumour cells obeys a functional Fokker--Planck equation which can be solved analytically. It is found that the density function exhibits an interesting "multi-peak" structure generated by cell fission as time evolves. Within this framework the action of therapy is also examined by simply incorporating a therapy term into the deterministic cell growth term.

  20. The lymphoid variant of hypereosinophilic syndrome: study of 21 patients with CD3-CD4+ aberrant T-cell phenotype.

    PubMed

    Lefèvre, Guillaume; Copin, Marie-Christine; Staumont-Sallé, Delphine; Avenel-Audran, Martine; Aubert, Hélène; Taieb, Alain; Salles, Gilles; Maisonneuve, Hervé; Ghomari, Kamel; Ackerman, Félix; Legrand, Fanny; Baruchel, André; Launay, David; Terriou, Louis; Leclech, Christian; Khouatra, Chahera; Morati-Hafsaoui, Chafika; Labalette, Myriam; Borie, Raphäel; Cotton, François; Gouellec, Noémie Le; Morschhauser, Franck; Trauet, Jacques; Roche-Lestienne, Catherine; Capron, Monique; Hatron, Pierre-Yves; Prin, Lionel; Kahn, Jean-Emmanuel

    2014-10-01

    The CD3-CD4+ aberrant T-cell phenotype is the most described in the lymphoid variant of hypereosinophilic syndrome (L-HES), a rare form of HES. Only a few cases have been reported, and data for these patients are scarce. To describe characteristics and outcome of CD3-CD4+ L-HES patients, we conducted a national multicentric retrospective study in the French Eosinophil Network. All patients who met the recent criteria of hypereosinophilia (HE) or HES and who had a persistent CD3-CD4+ T-cell subset on blood T-cell phenotyping were included. Clinical and laboratory data were retrospectively collected by chart review. CD3-CD4+ L-HES was diagnosed in 21 patients (13 females, median age 42 years [range, 5-75 yr]). Half (48%) had a history of atopic manifestations. Clinical manifestations were dermatologic (81%), superficial adenopathy (62%), rheumatologic (29%), gastrointestinal (24%), pulmonary (19%), neurologic (10%), and cardiovascular (5%). The median absolute CD3-CD4+ T-cell count was 0.35 G/L (range, 0.01-28.3), with a clonal TCRγδ rearrangement in 76% of patients. The mean follow-up duration after HES diagnosis was 6.9 ± 5.1 years. All patients treated with oral corticosteroids (CS) (n = 18) obtained remission, but 16 required CS-sparing treatments. One patient had a T-cell lymphoma 8 years after diagnosis, and 3 deaths occurred during follow-up.In conclusion, clinical manifestations related to CD3-CD4+ T cell-associated L-HES are not limited to skin, and can involve all tissue or organs affected in other types of HE. Contrary to FIP1L1-PDGFRA chronic eosinophilic leukemia patients, CS are always effective in these patients, but CS-sparing treatments are frequently needed. The occurrence of T-cell lymphoma, although rare in our cohort, remains a major concern during follow-up. PMID:25398061

  1. Aberrant TIRAP and MyD88 expression in B-cell chronic lymphocytic leukemia.

    PubMed

    Antosz, Halina; Sajewicz, Joanna; Marzec-Kotarska, Barbara; Dmoszyńska, Anna; Baszak, Jacek; Jargiełło-Baszak, Małgorzata

    2013-06-01

    TIRAP and Myd88 are adaptor proteins for Toll-like receptors-2 and -4 (TLR2/4) which are engaged in transducing the signal to downstream molecules. Several studies have shown the increased role of infection factors in pathogenesis of B cell chronic lymphocytic leukemia (B-CLL). This prompted us to test whether there is a correlation between MyD88-TIRAP dynamics before and after inflammatory stimuli. We determined the mRNA and protein expression of TIRAP and MyD88 in CD5(+)CD19(+) B-CLL cells and in a subpopulation of normal B CD19(+) lymphocytes. Additionally we determined the influence of lipopolysaccharide Escherichia coli - TLR4-ligand (LPS) and Staphylococcus aureus strain Cowan I - TLR2-ligand (SAC) on TIR-domain-containing adaptor protein, also called MyD88 adaptor-like (TIRAP) and myeloid differentiation primary response protein 88 (MyD88) expression. We have found that the mRNA and protein expression of TIRAP and MyD88 in B-CLL lymphocytes is lower compared with that in normal B lymphocytes. LPS and SAC stimulation in normal lymphocytes significantly altered neither TIRAP nor MyD88 mRNA expression, whereas TIRAP protein level substantially decreased after TLR agonist treatment. We did not observe any changes in MyD88 protein level after B lymphocyte stimulation. There was a significant increase in TIRAP mRNA expression after LPS and SAC stimulation of B-CLL cells. MyD88 mRNA expression levels in B-CLL lymphocytes slightly decreased upon treatment with either stimulator. Stimulation with TLR agonists did not cause changes in TIRAP and MyD88 expression at the protein level in B-CLL lymphocytes. The results of our study suggest that there may exist a, yet unknown, defect of TIRAP and MyD88 proteins in B-CLL lymphocytes. PMID:23419703

  2. Comparison of RBE values of high- LET α-particles for the induction of DNA-DSBs, chromosome aberrations and cell reproductive death

    PubMed Central

    2011-01-01

    Background Various types of radiation effects in mammalian cells have been studied with the aim to predict the radiosensitivity of tumours and normal tissues, e.g. DNA double strand breaks (DSB), chromosome aberrations and cell reproductive inactivation. However, variation in correlations with clinical results has reduced general application. An additional type of information is required for the increasing application of high-LET radiation in cancer therapy: the Relative Biological Effectiveness (RBE) for effects in tumours and normal tissues. Relevant information on RBE values might be derived from studies on cells in culture. Methods To evaluate relationships between DNA-DSB, chromosome aberrations and the clinically most relevant effect of cell reproductive death, for ionizing radiations of different LET, dose-effect relationships were determined for the induction of these effects in cultured SW-1573 cells irradiated with gamma-rays from a Cs-137 source or with α-particles from an Am-241 source. RBE values were derived for these effects. Ionizing radiation induced foci (IRIF) of DNA repair related proteins, indicative of DSB, were assessed by counting gamma-H2AX foci. Chromosome aberration frequencies were determined by scoring fragments and translocations using premature chromosome condensation. Cell survival was measured by colony formation assay. Analysis of dose-effect relations was based on the linear-quadratic model. Results Our results show that, although both investigated radiation types induce similar numbers of IRIF per absorbed dose, only a small fraction of the DSB induced by the low-LET gamma-rays result in chromosome rearrangements and cell reproductive death, while this fraction is considerably enhanced for the high-LET alpha-radiation. Calculated RBE values derived for the linear components of dose-effect relations for gamma-H2AX foci, cell reproductive death, chromosome fragments and colour junctions are 1.0 ± 0.3, 14.7 ± 5.1, 15.3 ± 5.9 and

  3. Aberrant T cell ERK pathway signaling and chromatin structure in lupus

    PubMed Central

    Gorelik, Gabriela; Richardson, Bruce

    2009-01-01

    Human systemic lupus erythematosus (SLE) is an autoimmune disease characterized by autoantibodies to nuclear components with subsequent immune complex formation and deposition in multiple organs. A combination of genetic and environmental factors is required for disease development, but how the environment interacts with the immune system in genetically predisposed hosts to cause lupus is unclear. Recent evidence suggests that environmental agents may alter T cell chromatin structure and gene expression through effects on DNA methylation, a repressive epigenetic mechanism promoting chromatin inactivation, to cause lupus in people with the appropriate genetic background. DNA methylation is regulated by ERK pathway signaling, and abnormalities in ERK pathway signaling may contribute to immune dysfunction in lupus through epigenetic effects on gene expression. This article reviews current evidence for epigenetic abnormalities, and in particular DNA demethylation, in the pathogenesis of idiopathic and some forms of drug induced lupus, and how impaired ERK pathway signaling may contribute to the development of human lupus through effects on T cell DNA methylation. PMID:18723128

  4. Induction of Chromosomal Aberrations in Human Cells after Irradiation with Filtered and Unfiltered Beams of 1 Gev/amu Iron Ions

    NASA Astrophysics Data System (ADS)

    Wilson, P.; Williams, A.; Nagasawa, H.; Peng, Y.; Chatterjee, A.; Bedford, J.

    To determine whether shielding materials that might be utilized for radiation protection of astronauts would affect the RBE of HZE particles such as those of concern for deep space missions we irradiated non cycling G0 monolayer cultures of contact inhibited normal human fibroblasts with 1 Gev amu iron ions with and without filtration with various thicknesses of Aluminum Al or polyethylene CH 2 and then measured the frequencies of chromosome-type aberrations dicentrics and excess fragments in the first post-irradiation mitosis Irradiations were carried out at the NRSL facility at Brookhaven National Laboratory For doses ranging up to 4 to 6 Gy the dose response for the total of these aberrations per cell was not significantly affected by beam filtrations up to 5 4 cm Al or up to 11 cm polyethylene relative to the unfiltered beam Neither was the dose response significantly different for unfiltered beams of 300 or 600 Mev amu iron ions relative to the 1 Gev amu iron ions The studies with 1 Gev amu iron ions were repeated four different times over a period of four years in each case with coded samples so the individual scoring aberrations would not know the irradiation conditions employed Comparison of the same effects in parallel experiments using 137 Cs gamma-rays allowed us to estimate that the RBE for aberration induction by these HZE iron ions for these acute high dose-rate exposures was approximately

  5. Role of Plasmacytoid Dendritic Cells for Aberrant Class II Expression in Exocrine Glands from Estrogen-Deficient Mice of Healthy Background

    PubMed Central

    Arakaki, Rieko; Nagaoka, Ai; Ishimaru, Naozumi; Yamada, Akiko; Yoshida, Satoko; Hayashi, Yoshio

    2009-01-01

    Although it has been well documented that aberrant major histocompatibility complex class II molecules may contribute to the development of autoimmune disorders, the precise mechanisms responsible for their tissue-specific expression remain unknown. Here we show that estrogen deficiency induces aberrant class II major histocompatibility complex expression in exocrine glands via interactions between epithelial cells and plasmacytoid dendritic cells. Relatively modest but functionally significant expression levels of major histocompatibility complex class II and class II transactivator molecules were observed in the exocrine glands of ovariectomized (Ovx) C57BL/6 (B6) mice, but were not seen in the exocrine glands of control B6 mice. We observed that the salivary dendritic cells adjacent to the apoptotic epithelial cells positive for terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling, were activated in Ovx mice, but were not activated in control mice. We obtained evidence that the salivary gland cells express both interferon regulatory factor-1 and class II transactivator type IV molecules in Ovx mice. Salivary gland cells from Ovx mice were also capable of inducing the activation of antigen-specific T cells from OT-II transgenic mice. These findings indicate that estrogen deficiency initiates class II transactivator type IV mRNA expression in exocrine glands via interactions between epithelial cells and plasmacytoid dendritic cells, suggesting that plasmacytoid dendritic cells play a pivotal role in gender-based autoimmune disorders in postmenopausal women. PMID:19359524

  6. mBAND analysis of chromosome aberrations in human epithelial cells induced by gamma-rays and secondary neutrons of low dose rate.

    PubMed

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

    2010-08-14

    Human risks from chronic exposures to both low- and high-LET radiation are of intensive research interest in recent years. In the present study, human epithelial cells were exposed in vitro to gamma-rays at a dose rate of 17 mGy/h or secondary neutrons of 25 mGy/h. The secondary neutrons have a broad energy spectrum that simulates the Earth's atmosphere at high altitude, as well as the environment inside spacecrafts like the Russian MIR station and the International Space Station (ISS). Chromosome aberrations in the exposed cells were analyzed using the multicolor banding in situ hybridization (mBAND) technique with chromosome 3 painted in 23 colored bands that allows identification of both inter- and intrachromosome exchanges including inversions. Comparison of present dose responses between gamma-rays and neutron irradiations for the fraction of cells with damaged chromosome 3 yielded a relative biological effectiveness (RBE) value of 26+/-4 for the secondary neutrons. Our results also revealed that secondary neutrons of low dose rate induced a higher fraction of intrachromosome exchanges than gamma-rays, but the fractions of inversions observed between these two radiation types were indistinguishable. Similar to the previous findings after acute radiation exposures, most of the inversions observed in the present study were accompanied by other aberrations. The fractions of complex type aberrations and of unrejoined chromosomal breakages were also found to be higher in the neutron-exposed cells than after gamma-rays. We further analyzed the location of the breaks involved in chromosome aberrations along chromosome 3, and observed hot spots after gamma-ray, but not neutron, exposures.

  7. mBAND analysis of chromosome aberrations in human epithelial cells induced by gamma-rays and secondary neutrons of low dose rate.

    PubMed

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

    2010-08-14

    Human risks from chronic exposures to both low- and high-LET radiation are of intensive research interest in recent years. In the present study, human epithelial cells were exposed in vitro to gamma-rays at a dose rate of 17 mGy/h or secondary neutrons of 25 mGy/h. The secondary neutrons have a broad energy spectrum that simulates the Earth's atmosphere at high altitude, as well as the environment inside spacecrafts like the Russian MIR station and the International Space Station (ISS). Chromosome aberrations in the exposed cells were analyzed using the multicolor banding in situ hybridization (mBAND) technique with chromosome 3 painted in 23 colored bands that allows identification of both inter- and intrachromosome exchanges including inversions. Comparison of present dose responses between gamma-rays and neutron irradiations for the fraction of cells with damaged chromosome 3 yielded a relative biological effectiveness (RBE) value of 26+/-4 for the secondary neutrons. Our results also revealed that secondary neutrons of low dose rate induced a higher fraction of intrachromosome exchanges than gamma-rays, but the fractions of inversions observed between these two radiation types were indistinguishable. Similar to the previous findings after acute radiation exposures, most of the inversions observed in the present study were accompanied by other aberrations. The fractions of complex type aberrations and of unrejoined chromosomal breakages were also found to be higher in the neutron-exposed cells than after gamma-rays. We further analyzed the location of the breaks involved in chromosome aberrations along chromosome 3, and observed hot spots after gamma-ray, but not neutron, exposures. PMID:20338263

  8. Chromosome aberrations induced by zebularine in triticale.

    PubMed

    Ma, Xuhui; Wang, Qing; Wang, Yanzhi; Ma, Jieyun; Wu, Nan; Ni, Shuang; Luo, Tengxiao; Zhuang, Lifang; Chu, Chenggen; Cho, Seong-Woo; Tsujimoto, Hisashi; Qi, Zengjun

    2016-07-01

    Chromosome engineering is an important approach for generating wheat germplasm. Efficient development of chromosome aberrations will facilitate the introgression and application of alien genes in wheat. In this study, zebularine, a DNA methylation transferase inhibitor, was successfully used to induce chromosome aberrations in the octoploid triticale cultivar Jinghui#1. Dry seeds were soaked in zebularine solutions (250, 500, and 750 μmol/L) for 24 h, and the 500 μmol/L treatment was tested in three additional treatment times, i.e., 12, 36, and 48 h. All treatments induced aberrations involving wheat and rye chromosomes. Of the 920 cells observed in 67 M1 plants, 340 (37.0%) carried 817 aberrations with an average of 0.89 aberrations per cell (range: 0-12). The aberrations included probable deletions, telosomes and acentric fragments (49.0%), large segmental translocations (28.9%), small segmental translocations (17.1%), intercalary translocations (2.6%), long chromosomes that could carry more than one centromere (2.0%), and ring chromosomes (0.5%). Of 510 M2 plants analyzed, 110 (21.6%) were found to carry stable aberrations. Such aberrations included 79 with varied rye chromosome numbers, 7 with wheat and rye chromosome translocations, 15 with possible rye telosomes/deletions, and 9 with complex aberrations involving variation in rye chromosome number and wheat-rye translocations. These indicated that aberrations induced by zebularine can be steadily transmitted, suggesting that zebularine is a new efficient agent for chromosome manipulation. PMID:27334255

  9. Aberrant Methylation Inactivates Somatostatin and Somatostatin Receptor Type 1 in Head and Neck Squamous Cell Carcinoma

    PubMed Central

    Misawa, Kiyoshi; Misawa, Yuki; Kondo, Haruki; Mochizuki, Daiki; Imai, Atsushi; Fukushima, Hirofumi; Uehara, Takayuki; Kanazawa, Takeharu; Mineta, Hiroyuki

    2015-01-01

    Purpose The aim of this study was to define somatostatin (SST) and somatostatin receptor type 1 (SSTR1) methylation profiles for head and neck squamous cell carcinoma (HNSCC) tumors at diagnosis and follow up and to evaluate their prognostic significance and value as a biomarker. Methods Gene expression was measured by quantitative RT-PCR. Promoter methylation status was determined by quantitative methylation-specific PCR (Q-MSP) in HNSCC. Results Methylation was associated with transcription inhibition. SST methylation in 81% of HNSCC tumor specimens significantly correlated with tumor size (P = 0.043), stage (P = 0.008), galanin receptor type 2 (GALR2) methylation (P = 0.041), and tachykinin-1 (TAC1) (P = 0.040). SSTR1 hypermethylation in 64% of cases was correlated with tumor size (P = 0.037), stage (P = 0.037), SST methylation (P < 0.001), and expression of galanin (P = 0.03), GALR2 (P = 0.014), TAC1 (P = 0.023), and tachykinin receptor type 1 (TACR1) (P = 0.003). SST and SSTR1 promoter hypermethylation showed highly discriminating receiver operator characteristic curve profiles, which clearly distinguished HNSCC from adjacent normal mucosal tissues. Concurrent hypermethylation of galanin and SSTR1 promoters correlated with reduced disease-free survival (log-rank test, P = 0.0001). Among patients with oral cavity and oropharynx cancer, methylation of both SST and SSTR1 promoters correlated with reduced disease-free survival (log-rank test, P = 0.028). In multivariate logistic-regression analysis, concomitant methylation of galanin and SSTR1 was associated with an odds ratio for recurrence of 12.53 (95% CI, 2.62 to 59.8; P = 0.002). Conclusions CpG hypermethylation is a likely mechanism of SST and SSTR1 gene inactivation, supporting the hypothesis that SST and SSTR1 play a role in the tumorigenesis of HNSCC and that this hypermethylation may serve as an important biomarker. PMID:25734919

  10. M-BAND Analysis of Chromosome Aberration In Human Epithelial Cells exposed to Gamma-ray and Secondary Neutrons of Low Dose Rate

    NASA Technical Reports Server (NTRS)

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

    2007-01-01

    High-energy secondary neutrons, produced by the interaction of galactic cosmic rays with the atmosphere, spacecraft structure and planetary surfaces, contribute to a significant fraction to the dose equivalent in crew members and passengers during commercial aviation travel, and astronauts in space missions. The Los Alamos Nuclear Science Center (LANSCE) neutron facility's "30L" beam line is known to generate neutrons that simulate the secondary neutron spectrum of the Earth's atmosphere at high altitude. The neutron spectrum is also similar to that measured onboard spacecraft like the MIR and the International Space Station (ISS). To evaluate the biological damage, we exposed human epithelial cells in vitro to the LANSCE neutron beams at an entrance dose rate of 2.5 cGy/hr or gamma-ray at 1.7cGy/hr, and assessed the induction of chromosome aberrations that were identified with mBAND. With this technique, individually painted chromosomal bands on one chromosome allowed the identification of inter-chromosomal aberrations (translocation to unpainted chromosomes) and intra-chromosomal aberrations (inversions and deletions within a single painted chromosome). Compared to our previous results for gamma-rays and 600 MeV/nucleon Fe ions of high dose rate, the neutron data showed a higher frequency of chromosome aberrations. However, detailed analysis of the inversion type revealed that all of the three radiation types in the study induced a low incidence of simple inversions. The low dose rate gamma-rays induced a lower frequency of chromosome aberrations than high dose rate gamma-rays, but the inversion spectrum was similar for the same cytotoxic effect. The distribution of damage sites on chromosome 3 for different radiation types will also be discussed.

  11. A recurrent 11q aberration pattern characterizes a subset of MYC-negative high-grade B-cell lymphomas resembling Burkitt lymphoma.

    PubMed

    Salaverria, Itziar; Martin-Guerrero, Idoia; Wagener, Rabea; Kreuz, Markus; Kohler, Christian W; Richter, Julia; Pienkowska-Grela, Barbara; Adam, Patrick; Burkhardt, Birgit; Claviez, Alexander; Damm-Welk, Christine; Drexler, Hans G; Hummel, Michael; Jaffe, Elaine S; Küppers, Ralf; Lefebvre, Christine; Lisfeld, Jasmin; Löffler, Markus; Macleod, Roderick A F; Nagel, Inga; Oschlies, Ilske; Rosolowski, Maciej; Russell, Robert B; Rymkiewicz, Grzegorz; Schindler, Detlev; Schlesner, Matthias; Scholtysik, René; Schwaenen, Carsten; Spang, Rainer; Szczepanowski, Monika; Trümper, Lorenz; Vater, Inga; Wessendorf, Swen; Klapper, Wolfram; Siebert, Reiner

    2014-02-20

    The genetic hallmark of Burkitt lymphoma (BL) is the t(8;14)(q24;q32) and its variants leading to activation of the MYC oncogene. It is a matter of debate whether true BL without MYC translocation exists. Here, we identified 59 lymphomas concordantly called BL by 2 gene expression classifiers among 753 B-cell lymphomas. Only 2 (3%) of these 59 molecular BL lacked a MYC translocation, which both shared a peculiar pattern of chromosome 11q aberration characterized by interstitial gains including 11q23.2-q23.3 and telomeric losses of 11q24.1-qter. We extended our analysis to 17 MYC-negative high-grade B-cell lymphomas with a similar 11q aberration and showed this aberration to be recurrently associated with morphologic and clinical features of BL. The minimal region of gain was defined by high-level amplifications in 11q23.3 and associated with overexpression of genes including PAFAH1B2 on a transcriptional and protein level. The recurrent region of loss contained a focal homozygous deletion in 11q24.2-q24.3 including the ETS1 gene, which was shown to be mutated in 4 of 16 investigated cases. These findings indicate the existence of a molecularly distinct subset of B-cell lymphomas reminiscent of BL, which is characterized by deregulation of genes in 11q.

  12. A recurrent 11q aberration pattern characterizes a subset of MYC-negative high-grade B-cell lymphomas resembling Burkitt lymphoma.

    PubMed

    Salaverria, Itziar; Martin-Guerrero, Idoia; Wagener, Rabea; Kreuz, Markus; Kohler, Christian W; Richter, Julia; Pienkowska-Grela, Barbara; Adam, Patrick; Burkhardt, Birgit; Claviez, Alexander; Damm-Welk, Christine; Drexler, Hans G; Hummel, Michael; Jaffe, Elaine S; Küppers, Ralf; Lefebvre, Christine; Lisfeld, Jasmin; Löffler, Markus; Macleod, Roderick A F; Nagel, Inga; Oschlies, Ilske; Rosolowski, Maciej; Russell, Robert B; Rymkiewicz, Grzegorz; Schindler, Detlev; Schlesner, Matthias; Scholtysik, René; Schwaenen, Carsten; Spang, Rainer; Szczepanowski, Monika; Trümper, Lorenz; Vater, Inga; Wessendorf, Swen; Klapper, Wolfram; Siebert, Reiner

    2014-02-20

    The genetic hallmark of Burkitt lymphoma (BL) is the t(8;14)(q24;q32) and its variants leading to activation of the MYC oncogene. It is a matter of debate whether true BL without MYC translocation exists. Here, we identified 59 lymphomas concordantly called BL by 2 gene expression classifiers among 753 B-cell lymphomas. Only 2 (3%) of these 59 molecular BL lacked a MYC translocation, which both shared a peculiar pattern of chromosome 11q aberration characterized by interstitial gains including 11q23.2-q23.3 and telomeric losses of 11q24.1-qter. We extended our analysis to 17 MYC-negative high-grade B-cell lymphomas with a similar 11q aberration and showed this aberration to be recurrently associated with morphologic and clinical features of BL. The minimal region of gain was defined by high-level amplifications in 11q23.3 and associated with overexpression of genes including PAFAH1B2 on a transcriptional and protein level. The recurrent region of loss contained a focal homozygous deletion in 11q24.2-q24.3 including the ETS1 gene, which was shown to be mutated in 4 of 16 investigated cases. These findings indicate the existence of a molecularly distinct subset of B-cell lymphomas reminiscent of BL, which is characterized by deregulation of genes in 11q. PMID:24398325

  13. Molecular crowding limits translation and cell growth.

    PubMed

    Klumpp, Stefan; Scott, Matthew; Pedersen, Steen; Hwa, Terence

    2013-10-15

    Bacterial growth is crucially dependent on protein synthesis and thus on the cellular abundance of ribosomes and related proteins. Here, we show that the slow diffusion of the bulky tRNA complexes in the crowded cytoplasm imposes a physical limit on the speed of translation, which ultimately limits the rate of cell growth. To study the required allocation of ancillary translational proteins to alleviate the effect of molecular crowding, we develop a model for cell growth based on a coarse-grained partitioning of the proteome. We find that coregulation of ribosome- and tRNA-affiliated proteins is consistent with measured growth-rate dependencies and results in near-optimal allocation over a broad range of growth rates. The analysis further resolves a long-standing controversy in bacterial growth physiology concerning the growth-rate dependence of translation speed and serves as a caution against premature identification of phenomenological parameters with mechanistic processes.

  14. A Regulatory Feedback between Plasmacytoid Dendritic Cells and Regulatory B Cells Is Aberrant in Systemic Lupus Erythematosus

    PubMed Central

    Menon, Madhvi; Blair, Paul A.; Isenberg, David A.; Mauri, Claudia

    2016-01-01

    Summary Signals controlling the generation of regulatory B (Breg) cells remain ill-defined. Here we report an “auto”-regulatory feedback mechanism between plasmacytoid dendritic cells (pDCs) and Breg cells. In healthy individuals, pDCs drive the differentiation of CD19+CD24hiCD38hi (immature) B cells into IL-10-producing CD24+CD38hi Breg cells and plasmablasts, via the release of IFN-α and CD40 engagement. CD24+CD38hi Breg cells conversely restrained IFN-α production by pDCs via IL-10 release. In systemic lupus erythematosus (SLE), this cross-talk was compromised; pDCs promoted plasmablast differentiation but failed to induce Breg cells. This defect was recapitulated in healthy B cells upon exposure to a high concentration of IFN-α. Defective pDC-mediated expansion of CD24+CD38hi Breg cell numbers in SLE was associated with altered STAT1 and STAT3 activation. Both altered pDC-CD24+CD38hi Breg cell interactions and STAT1-STAT3 activation were normalized in SLE patients responding to rituximab. We propose that alteration in pDC-CD24+CD38hi Breg cell interaction contributes to the pathogenesis of SLE. PMID:26968426

  15. Transient presence of clonal chromosomal aberrations in Ph-negative cells in patients with chronic myeloid leukemia remaining in deep molecular response on tyrosine kinase inhibitor treatment.

    PubMed

    Gniot, Michał; Lewandowski, Krzysztof; Ratajczak, Błażej; Lewandowska, Maria; Lehmann-Kopydłowska, Agata; Jarmuż-Szymczak, Małgorzata; Komarnicki, Mieczysław

    2014-01-01

    Advancements in treatment of chronic myeloid leukemia (CML) turned this formerly fatal neoplasm into a manageable chronic condition. Therapy with tyrosine kinase inhibitors (TKIs) often leads to significant reduction of disease burden, known as the deep molecular response (DMR). Herein, we decided to analyze the cohort of CML patients treated in our center with TKIs, who obtain and retain DMR for a period longer than 24 months. The aim of the study was to evaluate the frequency of clonal cytogenetic aberrations in Philadelphia-negative (Ph-) cells in patients with DMR during TKI treatment. The analyzed data was obtained during routine molecular and cytogenetic treatment monitoring, using G-banded trypsin and Giemsa stain (GTG) karyotyping and reverse transcription quantitative PCR. We noticed that approximately 50% of patients (28 of 55) in DMR had, at some follow-up point, transient changes in the karyotype of their Ph- bone marrow cells. In 9.1% of cases (5 of 55), the presence of the same aberrations was observed at different time points. The most frequently appearing aberrations were monosomies of chromosomes 19, 20, 21, and Y. Statistical analysis suggests that the occurrence of such abnormalities in CML patients correlates with the TKI treatment time. PMID:25496750

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

    PubMed

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

    2012-09-01

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

  17. Effects of caffeine and inhibitors of DNA synthesis on chromatid-type aberrations induced by acetaldehyde in root-tip cells.

    PubMed

    Cortés, F; Mateos, S; Ortiz, T; Piñero, J

    1987-10-01

    Root-tip cells of Allium cepa were exposed to acetaldehyde (AA) and post-treated with caffeine and 3 inhibitors of DNA synthesis, namely hydroxyurea (HU), 5-fluorodeoxyuridine (FdUrd), and arabinofuranosylcytosine (araC). Caffeine strongly potentiated the frequency of chromatid-type aberrations when given immediately after the AA treatment or as a 5-h treatment starting 10 h before the addition of colchicine. In contrast, no enhancement was observed when caffeine was present for the last 2.5 h, simultaneously with colchicine. The inhibitors of DNA synthesis were given following this last schedule. Both HU and FdUrd clearly enhanced the yield of AA-induced chromatid aberrations, while no enhancement of chromosome damage was observed after exposure to araC.

  18. The Aberrant DNA Methylation Profile of Human Induced Pluripotent Stem Cells Is Connected to the Reprogramming Process and Is Normalized During In Vitro Culture

    PubMed Central

    Tesarova, Lenka; Simara, Pavel; Stejskal, Stanislav; Koutna, Irena

    2016-01-01

    The potential clinical applications of human induced pluripotent stem cells (hiPSCs) are limited by genetic and epigenetic variations among hiPSC lines and the question of their equivalency with human embryonic stem cells (hESCs). We used MethylScreen technology to determine the DNA methylation profile of pluripotency and differentiation markers in hiPSC lines from different source cell types compared to hESCs and hiPSC source cells. After derivation, hiPSC lines compromised a heterogeneous population characterized by variable levels of aberrant DNA methylation. These aberrations were induced during somatic cell reprogramming and their levels were associated with the type of hiPSC source cells. hiPSC population heterogeneity was reduced during prolonged culture and hiPSCs acquired an hESC-like methylation profile. In contrast, the expression of differentiation marker genes in hiPSC lines remained distinguishable from that in hESCs. Taken together, in vitro culture facilitates hiPSC acquisition of hESC epigenetic characteristics. However, differences remain between both pluripotent stem cell types, which must be considered before their use in downstream applications. PMID:27336948

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

    PubMed Central

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

    2014-01-01

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

  20. The Aberrant DNA Methylation Profile of Human Induced Pluripotent Stem Cells Is Connected to the Reprogramming Process and Is Normalized During In Vitro Culture.

    PubMed

    Tesarova, Lenka; Simara, Pavel; Stejskal, Stanislav; Koutna, Irena

    2016-01-01

    The potential clinical applications of human induced pluripotent stem cells (hiPSCs) are limited by genetic and epigenetic variations among hiPSC lines and the question of their equivalency with human embryonic stem cells (hESCs). We used MethylScreen technology to determine the DNA methylation profile of pluripotency and differentiation markers in hiPSC lines from different source cell types compared to hESCs and hiPSC source cells. After derivation, hiPSC lines compromised a heterogeneous population characterized by variable levels of aberrant DNA methylation. These aberrations were induced during somatic cell reprogramming and their levels were associated with the type of hiPSC source cells. hiPSC population heterogeneity was reduced during prolonged culture and hiPSCs acquired an hESC-like methylation profile. In contrast, the expression of differentiation marker genes in hiPSC lines remained distinguishable from that in hESCs. Taken together, in vitro culture facilitates hiPSC acquisition of hESC epigenetic characteristics. However, differences remain between both pluripotent stem cell types, which must be considered before their use in downstream applications. PMID:27336948

  1. A Phase IIa Randomized, Double-Blind Trial of Erlotinib in Inhibiting Epidermal Growth Factor Receptor Signaling in Aberrant Crypt Foci of the Colorectum

    PubMed Central

    Gillen, Daniel L.; Meyskens, Frank L.; Morgan, Timothy R.; Zell, Jason; Carroll, Robert; Benya, Richard; Chen, Wen-Pin; Mo, Allen; Tucker, Chris; Bhattacharya, Asmita; Huang, Zhiliang; Arcilla, Myra; Wong, Vanessa; Chung, Jinah; Gonzalez, Rachel; Rodriguez, Luz Maria; Szabo, Eva; Rosenberg, Daniel W.; Lipkin, Steven M.

    2015-01-01

    Colorectal cancer (CRC) progresses through multiple distinct stages that are potentially amenable to chemopreventative intervention. Epidermal Growth Factor Receptor (EGFR) inhibitors are efficacious in advanced tumors including CRC. There is significant evidence that EGFR also plays important roles in CRC initiation, and that EGFR inhibitors block tumorigenesis. We performed a double-blind randomized clinical trial to test whether the EGFR inhibitor erlotinib given for up to 30 days had an acceptable safety and efficacy profile to reduce EGFR signaling biomarkers in colorectal aberrant crypt foci (ACF), a subset of which progress to CRC, and normal rectal tissue. A total of N=45 patients were randomized to one of three erlotinib doses (25 mg, 50 mg, 100 mg) with randomization stratified by non-steroidal anti-inflammatory drug (NSAID) use. There were no unanticipated adverse events with Erlotinib therapy. Erlotinib was detected in both normal rectal mucosa and ACFs. Colorectal ACF phosphoERK, phosphoEGFR and total EGFR signaling changes from baseline were modest and there was no dose response. Overall, this trial did not meet is primary efficacy endpoint. Colorectal EGFR signaling inhibition by erlotinib is therefore likely insufficient to merit further studies without additional pre-screening stratification or potentially longer duration of use. PMID:25604134

  2. A phase IIa randomized, double-blind trial of erlotinib in inhibiting epidermal growth factor receptor signaling in aberrant crypt foci of the colorectum.

    PubMed

    Gillen, Daniel L; Meyskens, Frank L; Morgan, Timothy R; Zell, Jason A; Carroll, Robert; Benya, Richard; Chen, Wen-Pin; Mo, Allen; Tucker, Chris; Bhattacharya, Asmita; Huang, Zhiliang; Arcilla, Myra; Wong, Vanessa; Chung, Jinah; Gonzalez, Rachel; Rodriguez, Luz Maria; Szabo, Eva; Rosenberg, Daniel W; Lipkin, Steven M

    2015-03-01

    Colorectal cancer progresses through multiple distinct stages that are potentially amenable to chemopreventative intervention. Epidermal growth factor receptor (EGFR) inhibitors are efficacious in advanced tumors including colorectal cancer. There is significant evidence that EGFR also plays important roles in colorectal cancer initiation, and that EGFR inhibitors block tumorigenesis. We performed a double-blind randomized clinical trial to test whether the EGFR inhibitor erlotinib given for up to 30 days had an acceptable safety and efficacy profile to reduce EGFR signaling biomarkers in colorectal aberrant crypt foci (ACF), a subset of which progress to colorectal cancer, and normal rectal tissue. A total of 45 patients were randomized to one of three erlotinib doses (25, 50, and 100 mg) with randomization stratified by nonsteroidal anti-inflammatory drug (NSAID) use. There were no unanticipated adverse events with erlotinib therapy. Erlotinib was detected in both normal rectal mucosa and ACFs. Colorectal ACF phosphorylated ERK (pERK), phosphorylated EGFR (pEGFR), and total EGFR signaling changes from baseline were modest and there was no dose response. Overall, this trial did not meet is primary efficacy endpoint. Colorectal EGFR signaling inhibition by erlotinib is therefore likely insufficient to merit further studies without additional prescreening stratification or potentially longer duration of use.

  3. Th22 cells increase in poor prognosis multiple myeloma and promote tumor cell growth and survival

    PubMed Central

    Di Lullo, Giulia; Marcatti, Magda; Heltai, Silvia; Brunetto, Emanuela; Tresoldi, Cristina; Bondanza, Attilio; Bonini, Chiara; Ponzoni, Maurilio; Tonon, Giovanni; Ciceri, Fabio; Bordignon, Claudio; Protti, Maria Pia

    2015-01-01

    There is increased production of plasmacytoid dendritic cells (pDCs) in the bone marrow (BM) of multiple myeloma (MM) patients and these favor Th22 cell differentiation. Here, we found that the frequency of interleukin (IL)-22+IL-17−IL-13+ T cells is significantly increased in peripheral blood (PB) and BM of stage III and relapsed/refractory MM patients compared with healthy donors and patients with asymptomatic or stage I/II disease. Th22 cells cloned from the BM of MM patients were CCR6+CXCR4+CCR4+CCR10− and produced IL-22 and IL-13 but not IL-17. Furthermore, polyfunctional Th22-Th2 and Th22-Th1 clones were identified based on the co-expression of additional chemokine receptors and cytokines (CRTh2 or CXCR3 and IL-5 or interferon gamma [IFNγ], respectively). A fraction of MM cell lines and primary tumors aberrantly expressed the IL-22RA1 and IL-22 induced STAT-3 phosphorylation, cell growth, and resistance to drug-induced cell death in MM cells. IL-13 treatment of normal BM mesenchymal stromal cells (MSCs) induced STAT-6 phosphorylation, adhesion molecule upregulation, and increased IL-6 production and significantly favored MM cell growth compared with untreated BM MSCs. Collectively, our data show that increased frequency of IL-22+IL-17−IL-13+ T cells correlates with poor prognosis in MM through IL-22 and IL-13 protumor activity and suggest that interference with IL-22 and IL-13 signaling pathways could be exploited for therapeutic intervention. PMID:26155400

  4. Hormone dependency of chromosome aberrations induced by 7,12-dimethylbenz(a)anthracene in rat bone marrow cells: site-specific increase by erythropoietin

    SciTech Connect

    Ueda, N.; Suglyama, T.; Chattopadhyay, S.C.; Goto-Mimura, K.; Maeda, S.

    1981-08-01

    The frequency of chromosome aberrations (CA) 6 hours after iv injection of 50 mg 7,12-dimethylbenz(a)anthracene (DMBA0/kg was studied in bone marrow cells of the noninbred Long-Evans rat under various hematopoietic conditions. The percentage of metaphase cells with CA was enhanced by anemia and suppressed by polycythemia. The low incidence of CA in polycythemic rats was reversed by 6 U of sheep erythropoietin (EP) injected at the time of DMBA treatment. The interchromosomal and intrachromosomal distribution of CA indicated that hematopoietic stimuli, more specifically EP, greatly enhanced DMBA-induced CA in specific chromosomal regions.

  5. Growth regulation of cultured human nevus cells.

    PubMed

    Mancianti, M L; Györfi, T; Shih, I M; Valyi-Nagy, I; Levengood, G; Menssen, H D; Halpern, A C; Elder, D E; Herlyn, M

    1993-03-01

    Cells isolated from congenital melanocytic nevi and cultured in vitro have growth characteristics that resemble their premalignant stage in situ. A serum-free, chemically defined medium has been developed that allows continuous growth of established nevus cultures for up to several months. Like primary melanoma cells, nevus cells in high-calcium-containing W489 medium require insulin for growth. In contrast to melanoma cells, nevus cells in serum-free medium require the presence of alpha-melanocyte-stimulating hormone, which enhanced intracellular levels of cyclic adenosine monophosphate. In contrast to the requirements of normal human melanocytes from newborn foreskin, congenital nevus cells grow with less dependency on basic fibroblast growth factor (bFGF). Nevus cultures contain bFGF-like activity, and they express bFGF mRNA. Nevic cells of compound nevi also express bFGF mRNA in situ but only in the junctional areas. These results indicate that bFGF plays an important growth regulatory role for nevus cells in vitro and in vivo. PMID:8440904

  6. Cloned Hemoglobin Genes Enhance Growth Of Cells

    NASA Technical Reports Server (NTRS)

    Khosla, Chaitan; Bailey, James E.

    1991-01-01

    Experiments show that portable deoxyribonucleic acid (DNA) sequences incorporated into host cells make them produce hemoglobins - oxygen-binding proteins essential to function of red blood cells. Method useful in several biotechnological applications. One, enhancement of growth of cells at higher densities. Another, production of hemoglobin to enhance supplies of oxygen in cells, for use in chemical reactions requiring oxygen, as additive to serum to increase transport of oxygen, and for binding and separating oxygen from mixtures of gases.

  7. Chromosome Aberrations by Heavy Ions

    NASA Astrophysics Data System (ADS)

    Ballarini, Francesca; Ottolenghi, Andrea

    It is well known that mammalian cells exposed to ionizing radiation can show different types of chromosome aberrations (CAs) including dicentrics, translocations, rings, deletions and complex exchanges. Chromosome aberrations are a particularly relevant endpoint in radiobiology, because they play a fundamental role in the pathways leading either to cell death, or to cell conversion to malignancy. In particular, reciprocal translocations involving pairs of specific genes are strongly correlated (and probably also causally-related) with specific tumour types; a typical example is the BCR-ABL translocation for Chronic Myeloid Leukaemia. Furthermore, aberrations can be used for applications in biodosimetry and more generally as biomarkers of exposure and risk, that is the case for cancer patients monitored during Carbon-ion therapy and astronauts exposed to space radiation. Indeed hadron therapy and astronauts' exposure to space radiation represent two of the few scenarios where human beings can be exposed to heavy ions. After a brief introduction on the main general features of chromosome aberrations, in this work we will address key aspects of the current knowledge on chromosome aberration induction, both from an experimental and from a theoretical point of view. More specifically, in vitro data will be summarized and discussed, outlining important issues such as the role of interphase death/mitotic delay and that of complex-exchange scoring. Some available in vivo data on cancer patients and astronauts will be also reported, together with possible interpretation problems. Finally, two of the few available models of chromosome aberration induction by ionizing radiation (including heavy ions) will be described and compared, focusing on the different assumptions adopted by the authors and on how these models can deal with heavy ions.

  8. IgA1-secreting cell lines from patients with IgA nephropathy produce aberrantly glycosylated IgA1.

    PubMed

    Suzuki, Hitoshi; Moldoveanu, Zina; Hall, Stacy; Brown, Rhubell; Vu, Huong L; Novak, Lea; Julian, Bruce A; Tomana, Milan; Wyatt, Robert J; Edberg, Jeffrey C; Alarcón, Graciela S; Kimberly, Robert P; Tomino, Yasuhiko; Mestecky, Jiri; Novak, Jan

    2008-02-01

    Aberrant glycosylation of IgA1 plays an essential role in the pathogenesis of IgA nephropathy. This abnormality is manifested by a deficiency of galactose in the hinge-region O-linked glycans of IgA1. Biosynthesis of these glycans occurs in a stepwise fashion beginning with the addition of N-acetylgalactosamine by the enzyme N-acetylgalactosaminyltransferase 2 and continuing with the addition of either galactose by beta1,3-galactosyltransferase or a terminal sialic acid by a N-acetylgalactosamine-specific alpha2,6-sialyltransferase. To identify the molecular basis for the aberrant IgA glycosylation, we established EBV-immortalized IgA1-producing cells from peripheral blood cells of patients with IgA nephropathy. The secreted IgA1 was mostly polymeric and had galactose-deficient O-linked glycans, characterized by a terminal or sialylated N-acetylgalactosamine. As controls, we showed that EBV-immortalized cells from patients with lupus nephritis and healthy individuals did not produce IgA with the defective galactosylation pattern. Analysis of the biosynthetic pathways in cloned EBV-immortalized cells from patients with IgA nephropathy indicated a decrease in beta1,3-galactosyltransferase activity and an increase in N-acetylgalactosamine-specific alpha2,6-sialyltransferase activity. Also, expression of beta1,3-galactosyltransferase was significantly lower, and that of N-acetylgalactosamine-specific alpha2,6-sialyltransferase was significantly higher than the expression of these genes in the control cells. Thus, our data suggest that premature sialylation likely contributes to the aberrant IgA1 glycosylation in IgA nephropathy and may represent a new therapeutic target.

  9. Nicotine derived genotoxic effects in human primary parotid gland cells as assessed in vitro by comet assay, cytokinesis-block micronucleus test and chromosome aberrations test.

    PubMed

    Ginzkey, Christian; Steussloff, Gudrun; Koehler, Christian; Burghartz, Marc; Scherzed, Agmal; Hackenberg, Stephan; Hagen, Rudolf; Kleinsasser, Norbert H

    2014-08-01

    Genotoxic effects of nicotine were described in different human cells including salivary gland cells. Based on the high nicotine concentration in saliva of smokers or patients using therapeutic nicotine patches, the current study was performed to evaluate the genotoxic potential of nicotine in human salivary gland cells. Therefore, primary salivary gland cells from 10 patients undergoing parotid gland surgery were exposed to nicotine concentrations between 1 μM and 1000 μM for 1 h in the absence of exogenous metabolic activation. The acinar phenotype was proven by immunofluorescent staining of alpha-amylase. Genotoxic effects were evaluated using the Comet assay, the micronucleus test and the chromosome aberration test. Cytotoxicity and apoptosis were determined by trypan blue exclusion test and Caspase-3 assay. Nicotine was able to induce genotoxic effects in all three assays. The chromosome aberration test was the most sensitive and increases in numerical and structural (chromatid-type and chromosome-type) aberrations were seen at ≥1 μM, whereas increases in micronuclei frequency were detected at 10 μM and DNA damage as measured in the Comet assay was noted at >100 μM. No cytotoxic damage or influence of apoptosis could be demonstrated. Nicotine as a possible risk factor for tumor initiation in salivary glands is still discussed controversially. Our results demonstrated the potential of nicotine to induce genotoxic effects in salivary gland cells. These results were observed at saliva nicotine levels similar to those found after oral or transdermal exposure to nicotine and suggest the necessity of careful monitoring of the use of nicotine in humans. PMID:24698733

  10. IgA1-secreting cell lines from patients with IgA nephropathy produce aberrantly glycosylated IgA1

    PubMed Central

    Suzuki, Hitoshi; Moldoveanu, Zina; Hall, Stacy; Brown, Rhubell; Vu, Huong L.; Novak, Lea; Julian, Bruce A.; Tomana, Milan; Wyatt, Robert J.; Edberg, Jeffrey C.; Alarcón, Graciela S.; Kimberly, Robert P.; Tomino, Yasuhiko; Mestecky, Jiri; Novak, Jan

    2008-01-01

    Aberrant glycosylation of IgA1 plays an essential role in the pathogenesis of IgA nephropathy. This abnormality is manifested by a deficiency of galactose in the hinge-region O-linked glycans of IgA1. Biosynthesis of these glycans occurs in a stepwise fashion beginning with the addition of N-acetylgalactosamine by the enzyme N-acetylgalactosaminyltransferase 2 and continuing with the addition of either galactose by β1,3-galactosyltransferase or a terminal sialic acid by a N-acetylgalactosamine–specific α2,6-sialyltransferase. To identify the molecular basis for the aberrant IgA glycosylation, we established EBV-immortalized IgA1-producing cells from peripheral blood cells of patients with IgA nephropathy. The secreted IgA1 was mostly polymeric and had galactose-deficient O-linked glycans, characterized by a terminal or sialylated N-acetylgalactosamine. As controls, we showed that EBV-immortalized cells from patients with lupus nephritis and healthy individuals did not produce IgA with the defective galactosylation pattern. Analysis of the biosynthetic pathways in cloned EBV-immortalized cells from patients with IgA nephropathy indicated a decrease in β1,3-galactosyltransferase activity and an increase in N-acetylgalactosamine–specific α2,6-sialyltransferase activity. Also, expression of β1,3-galactosyltransferase was significantly lower, and that of N-acetylgalactosamine–specific α2,6-sialyltransferase was significantly higher than the expression of these genes in the control cells. Thus, our data suggest that premature sialylation likely contributes to the aberrant IgA1 glycosylation in IgA nephropathy and may represent a new therapeutic target. PMID:18172551

  11. Aberrant activation of nuclear factor of activated T cell 2 in lamina propria mononuclear cells in ulcerative colitis

    PubMed Central

    Shih, Tsung-Chieh; Hsieh, Sen-Yung; Hsieh, Yi-Yueh; Chen, Tse-Chin; Yeh, Chien-Yu; Lin, Chun-Jung; Lin, Deng-Yn; Chiu, Cheng-Tang

    2008-01-01

    AIM: To investigate the role of nuclear factor of activated T cell 2 (NFAT2), the major NFAT protein in peripheral T cells, in sustained T cell activation and intractable inflammation in human ulcerative colitis (UC). METHODS: We used two-dimensional gel-electrophoresis, immunohistochemistry, double immunohistochemical staining, and confocal microscopy to inspect the expression of NFAT2 in 107, 15, 48 and 5 cases of UC, Crohn’s disease (CD), non-specific colitis, and 5 healthy individuals, respectively. RESULTS: Up-regulation with profound nucleo-translocation/activation of NFAT2 of lamina propria mononuclear cells (LPMC) of colonic mucosa was found specifically in the affected colonic mucosa from patients with UC, as compared to CD or NC (P < 0.001, Kruskal-Wallis test). Nucleo-translocation/activation of NFAT2 primarily occurred in CD8+T, but was less prominent in CD4+ T cells or CD20+B cells. It was strongly associated with the disease activity, including endoscopic stage (τ = 0.2145, P = 0.0281) and histologic grade (τ = 0.4167, P < 0.001). CONCLUSION: We disclose for the first time the nucleo-translocation/activatin of NFAT2 in lamina propria mononuclear cells in ulcerative colitis. Activation of NFAT2 was specific for ulcerative colitis and highly associated with disease activity. Since activation of NFAT2 is implicated in an auto-regulatory positive feedback loop of sustained T-cell activation and NFAT proteins play key roles in the calcium/calcineurin signaling pathways, our results not only provide new insights into the mechanism for sustained intractable inflammation, but also suggest the calcium-calcineurin/NFAT pathway as a new therapeutic target for ulcerative colitis. PMID:18350607

  12. The aberrantly expressed miR-193b-3p contributes to preeclampsia through regulating transforming growth factor-β signaling

    PubMed Central

    Zhou, Xinyao; Li, Qiaoli; Xu, Jiawei; Zhang, Xiaojing; Zhang, Huijuan; Xiang, Yuqian; Fang, Chuantao; Wang, Teng; Xia, Shihui; Zhang, Qiang; Xing, Qinghe; He, Lin; Wang, Lei; Xu, Mingqing; Zhao, Xinzhi

    2016-01-01

    Preeclampsia (PE) is a leading cause of maternal mortality worldwide. Several studies have detected some differentially expressed microRNAs in the preeclamptic placenta, but few of the identified microRNAs demonstrated consistent findings among different research studies. In this study, high-throughput microRNA sequencing (HTS) of 9 preeclamptic and 9 normal placentas was performed. Seventeen microRNAs were identified to be up-regulated, and 8 down-regulated in preeclamptic placentas. Eight differentially expressed microRNAs except one identified in our study were determined to be consistent with at least one previous study, while sixteen were newly found. We performed qRT-PCR with independent 22 preeclamptic placentas and 20 control placentas to verify the differentially expressed microRNAs, and ten microRNAs were validated. The predicted target genes of the aberrantly expressed miR-193b-3p were enriched in the following gene ontology categories: cell motility and migration, cell proliferation and angiogenesis. We also found that miR-193b-3p significantly decreased the migration and invasion of trophoblast (HTR-8/SVneo) cells and that miR-193b-3p could regulate trophoblasts migration and invasion through binding onto the 3′UTR target site of TGF-β2. In conclusion, we identified a list of differentially expressed microRNAs in PE placentas by HTS and provided preliminary evidence for the role of miR-193b-3p in the pathogenesis of preeclampsia. PMID:26822621

  13. Shape of growth cells in directional solidification.

    PubMed

    Pocheau, A; Georgelin, M

    2006-01-01

    The purpose of this study is to characterize experimentally the whole shape of the growth cells displayed in directional solidification and its evolution with respect to control parameters. A library of cells is first built up from observation of directional solidification of a succinonitrile alloy in a large range of pulling velocity, cell spacing, and thermal gradient. Cell boundaries are then extracted from these images and fitted by trial functions on their whole profile, from cell tip to cell grooves. A coherent evolution of the fit parameters with the control parameters is evidenced. It enables us to characterize the whole cell shape by a single function involving only two parameters which vary smoothly in the control parameter space. This, in particular, evidences a continuous evolution of the cell geometry at the cell to dendrite transition which denies the existence of a change of branch of solutions at the occurrence of sidebranching. More generally, this global determination of cell shape complemented with a previous determination of the position of cells in the thermal field (the cell tip undercooling) provides a complete characterization of growth solutions and of their evolutions in this system. It thus brings about a relevant framework for testing and improving theoretical and numerical understanding of cell shapes and cell stability in directional solidification.

  14. Simulations of DSB Yields and Radiation-induced Chromosomal Aberrations in Human Cells Based on the Stochastic Track Structure Induced by HZE Particles

    NASA Technical Reports Server (NTRS)

    Ponomarev, Artem; Plante, Ianik; George, Kerry; Wu, Honglu

    2014-01-01

    The formation of double-strand breaks (DSBs) and chromosomal aberrations (CAs) is of great importance in radiation research and, specifically, in space applications. We are presenting a new particle track and DNA damage model, in which the particle stochastic track structure is combined with the random walk (RW) structure of chromosomes in a cell nucleus. The motivation for this effort stems from the fact that the model with the RW chromosomes, NASARTI (NASA radiation track image) previously relied on amorphous track structure, while the stochastic track structure model RITRACKS (Relativistic Ion Tracks) was focused on more microscopic targets than the entire genome. We have combined chromosomes simulated by RWs with stochastic track structure, which uses nanoscopic dose calculations performed with the Monte-Carlo simulation by RITRACKS in a voxelized space. The new simulations produce the number of DSBs as function of dose and particle fluence for high-energy particles, including iron, carbon and protons, using voxels of 20 nm dimension. The combined model also calculates yields of radiation-induced CAs and unrejoined chromosome breaks in normal and repair deficient cells. The joined computational model is calibrated using the relative frequencies and distributions of chromosomal aberrations reported in the literature. The model considers fractionated deposition of energy to approximate dose rates of the space flight environment. The joined model also predicts of the yields and sizes of translocations, dicentrics, rings, and more complex-type aberrations formed in the G0/G1 cell cycle phase during the first cell division after irradiation. We found that the main advantage of the joined model is our ability to simulate small doses: 0.05-0.5 Gy. At such low doses, the stochastic track structure proved to be indispensable, as the action of individual delta-rays becomes more important.

  15. Simulations of DSB Yields and Radiation-induced Chromosomal Aberrations in Human Cells Based on the Stochastic Track Structure iIduced by HZE Particles

    NASA Technical Reports Server (NTRS)

    Ponomarev, Artem; Plante, Ianik; George, Kerry; Wu, Honglu

    2014-01-01

    The formation of double-strand breaks (DSBs) and chromosomal aberrations (CAs) is of great importance in radiation research and, specifically, in space applications. We are presenting a new particle track and DNA damage model, in which the particle stochastic track structure is combined with the random walk (RW) structure of chromosomes in a cell nucleus. The motivation for this effort stems from the fact that the model with the RW chromosomes, NASARTI (NASA radiation track image) previously relied on amorphous track structure, while the stochastic track structure model RITRACKS (Relativistic Ion Tracks) was focused on more microscopic targets than the entire genome. We have combined chromosomes simulated by RWs with stochastic track structure, which uses nanoscopic dose calculations performed with the Monte-Carlo simulation by RITRACKS in a voxelized space. The new simulations produce the number of DSBs as function of dose and particle fluence for high-energy particles, including iron, carbon and protons, using voxels of 20 nm dimension. The combined model also calculates yields of radiation-induced CAs and unrejoined chromosome breaks in normal and repair deficient cells. The joined computational model is calibrated using the relative frequencies and distributions of chromosomal aberrations reported in the literature. The model considers fractionated deposition of energy to approximate dose rates of the space flight environment. The joined model also predicts of the yields and sizes of translocations, dicentrics, rings, and more complex-type aberrations formed in the G0/G1 cell cycle phase during the first cell division after irradiation. We found that the main advantage of the joined model is our ability to simulate small doses: 0.05-0.5 Gy. At such low doses, the stochastic track structure proved to be indispensable, as the action of individual delta-rays becomes more important.

  16. Aberrant DNA Methylation in Keratoacanthoma

    PubMed Central

    Nakagawa, Hidemi

    2016-01-01

    Background Keratoacanthoma (KA) is a self-limiting epidermal tumor for which histopathological examination sometimes suggests malignancy. Based on inconsistent clinical views, KA can be regarded as both a benign tumor and a variant of squamous cell carcinoma (SCC). Aberrant DNA methylation frequently occurs in malignant tumors but it scarcely occurs in benign tumors. Whether aberrant methylation occurs in KA has not been previously examined. Objective The aim is to elucidate whether aberrant methylation of CpG islands (CGI) containing a high density of cytosine-guanine dinucleotide (CpG) sites occurs in KA. Methods Five SCC cell lines, two cultured samples of normal human epidermal keratinocytes (NHEKs), 18 clinical SCC samples, and 21 clinical KA samples were analyzed with Infinium HumanMethylation450 BeadChips, quantitative real-time methylation-specific PCR (RT-MSP) and/or bisulfite sequencing. Results Genome-wide analyses of NHEK, KA, and SCC indicated that there was a greater number of aberrantly hypermethylated CGIs in SCC than in KA and there were aberrantly hypermethylated CGIs which are common in both. Among the common hypermethylated CGIs, RT-MSP and bisulfite sequencing targeting CGIs located on CCDC17, PVR, and MAP3K11 gene bodies also showed that methylation levels were significantly higher in KA than in normal epidermis. Statistical analyses suggested that the methylation level of CGI located on PVR in SCC might be correlated to lymph node metastasis (P = 0.013, Mann-Whitney U test) and that the methylation level of CGI in MAP3K11 in KA might be correlated to age (P = 0.031, linear regression analysis). Conclusion Aberrant DNA methylation occurs in KA. PMID:27788211

  17. Role of bentonite clays on cell growth.

    PubMed

    Cervini-Silva, Javiera; Ramírez-Apan, María Teresa; Kaufhold, Stephan; Ufer, Kristian; Palacios, Eduardo; Montoya, Ascención

    2016-04-01

    Bentonites, naturally occurring clays, are produced industrially because of their adsorbent capacity but little is known about their effects on human health. This manuscript reports on the effect of bentonites on cell growth behaviour. Bentonites collected from India (Bent-India), Hungary (Bent-Hungary), Argentina (Bent-Argentina), and Indonesia (Bent-Indonesia) were studied. All four bentonites were screened in-vitro against two human cancer cell lines [U251 (central nervous system, glioblastoma) and SKLU-1 (lung adenocarcinoma)] supplied by the National Cancer Institute (USA). Bentonites induced growth inhibition in the presence of U251 cells, and growth increment in the presence of SKLU-1 cells, showing that interactions between bentonite and cell surfaces were highly specific. The proliferation response for U251 cells was explained because clay surfaces controlled the levels of metabolic growth components, thereby inhibiting the development of high-grade gliomas, particularly primary glioblastomas. On the other hand, the proliferation response for SKLU-1 was explained by an exacerbated growth favoured by swelling, and concomitant accumulation of solutes, and their hydration and transformation via clay-surface mediated reactions. PMID:26849195

  18. Role of bentonite clays on cell growth.

    PubMed

    Cervini-Silva, Javiera; Ramírez-Apan, María Teresa; Kaufhold, Stephan; Ufer, Kristian; Palacios, Eduardo; Montoya, Ascención

    2016-04-01

    Bentonites, naturally occurring clays, are produced industrially because of their adsorbent capacity but little is known about their effects on human health. This manuscript reports on the effect of bentonites on cell growth behaviour. Bentonites collected from India (Bent-India), Hungary (Bent-Hungary), Argentina (Bent-Argentina), and Indonesia (Bent-Indonesia) were studied. All four bentonites were screened in-vitro against two human cancer cell lines [U251 (central nervous system, glioblastoma) and SKLU-1 (lung adenocarcinoma)] supplied by the National Cancer Institute (USA). Bentonites induced growth inhibition in the presence of U251 cells, and growth increment in the presence of SKLU-1 cells, showing that interactions between bentonite and cell surfaces were highly specific. The proliferation response for U251 cells was explained because clay surfaces controlled the levels of metabolic growth components, thereby inhibiting the development of high-grade gliomas, particularly primary glioblastomas. On the other hand, the proliferation response for SKLU-1 was explained by an exacerbated growth favoured by swelling, and concomitant accumulation of solutes, and their hydration and transformation via clay-surface mediated reactions.

  19. Regulatory T-cell depletion in the gut caused by integrin β7 deficiency exacerbates DSS colitis by evoking aberrant innate immunity.

    PubMed

    Zhang, H L; Zheng, Y J; Pan, Y D; Xie, C; Sun, H; Zhang, Y H; Yuan, M Y; Song, B L; Chen, J F

    2016-03-01

    Integrin α4β7 controls lymphocyte trafficking into the gut and has essential roles in inflammatory bowel disease (IBD). The α4β7-blocking antibody vedolizumab is approved for IBD treatment; however, high dose of vedolizumab aggravates colitis in a small percentage of patients. Herein, we show that integrin β7 deficiency results in colonic regulatory T (Treg) cell depletion and exacerbates dextran sulfate sodium (DSS) colitis by evoking aberrant innate immunity. In DSS-treated β7-deficient mice, the loss of colonic Treg cells induces excessive macrophage infiltration in the colon via upregulation of colonic epithelial intercellular adhesion molecule 1 and increases proinflammatory cytokine expression, thereby exacerbating DSS-induced colitis. Moreover, reconstitution of the colonic Treg cell population in β7-deficient mice suppresses aberrant innate immune response in the colon and attenuates DSS colitis. Thus, integrin α4β7 is essential for suppression of DSS colitis as it regulates the colonic Treg cell population and innate immunity.

  20. Modeling cell response to low doses of photon irradiation: Part 2--application to radiation-induced chromosomal aberrations in human carcinoma cells.

    PubMed

    Cunha, Micaela; Testa, Etienne; Komova, Olga V; Nasonova, Elena A; Mel'nikova, Larisa A; Shmakova, Nina L; Beuve, Michaël

    2016-03-01

    The biological phenomena observed at low doses of ionizing radiation (adaptive response, bystander effects, genomic instability, etc.) are still not well understood. While at high irradiation doses, cellular death may be directly linked to DNA damage, at low doses, other cellular structures may be involved in what are known as non-(DNA)-targeted effects. Mitochondria, in particular, may play a crucial role through their participation in a signaling network involving oxygen/nitrogen radical species. According to the size of the implicated organelles, the fluctuations in the energy deposited into these target structures may impact considerably the response of cells to low doses of ionizing irradiation. Based on a recent simulation of these fluctuations, a theoretical framework was established to have further insight into cell responses to low doses of photon irradiation, namely the triggering of radioresistance mechanisms by energy deposition into specific targets. Three versions of a model are considered depending on the target size and on the number of targets that need to be activated by energy deposition to trigger radioresistance mechanisms. These model versions are applied to the fraction of radiation-induced chromosomal aberrations measured at low doses in human carcinoma cells (CAL51). For this cell line, it was found in the present study that the mechanisms of radioresistance could not be triggered by the activation of a single small target (nanometric size, 100 nm), but could instead be triggered by the activation of a large target (micrometric, 10 μm) or by the activation of a great number of small targets. The mitochondria network, viewed either as a large target or as a set of small units, might be concerned by these low-dose effects. PMID:26708100

  1. Characterization of gene rearrangements resulted from genomic structural aberrations in human esophageal squamous cell carcinoma KYSE150 cells.

    PubMed

    Hao, Jia-Jie; Gong, Ting; Zhang, Yu; Shi, Zhi-Zhou; Xu, Xin; Dong, Jin-Tang; Zhan, Qi-Min; Fu, Song-Bin; Wang, Ming-Rong

    2013-01-15

    Chromosomal rearrangements and involved genes have been reported to play important roles in the development and progression of human malignancies. But the gene rearrangements in esophageal squamous cell carcinoma (ESCC) remain to be identified. In the present study, array-based comparative genomic hybridization (array-CGH) was performed on the ESCC cell line KYSE150. Eight disrupted genes were detected according to the obviously distinct unbalanced breakpoints. The splitting of these genes was validated by dual-color fluorescence in-situ hybridization (FISH). By using rapid amplification of cDNA ends (RACE), genome walking and sequencing analysis, we further identified gene disruptions and rearrangements. A fusion transcript DTL-1q42.2 was derived from an intrachromosomal rearrangement of chromosome 1. Highly amplified segments of DTL and PTPRD were self-rearranged. The sequences on either side of the junctions possess micro-homology with each other. FISH results indicated that the split DTL and PTPRD were also involved in comprising parts of the derivative chromosomes resulted from t(1q;9p;12p) and t(9;1;9). Further, we found that regions harboring DTL (1q32.3) and PTPRD (9p23) were also splitting in ESCC tumors. The data supplement significant information on the existing genetic background of KYSE150, which may be used as a model for studying these gene rearrangements.

  2. The pituitary growth hormone cell in space

    NASA Technical Reports Server (NTRS)

    Hymer, Wesley C.; Grindeland, R.

    1989-01-01

    Growth hormone (GH), produced and secreted from specialized cells in the pituitary gland, controls the metabolism of protein, fat, and carbohydrate. It is also probably involved in the regulation of proper function of bone, muscle and immune systems. The behavior of the GH cell system was studied by flying either isolated pituitary cells or live rats. In the latter case, pituitary GH cells are prepared on return to earth and then either transplanted into hypophysectomized rats or placed into cell culture so that function of GH cells in-vivo vs. in-vitro can be compared. The results from three flights to date (STS-8, 1983; SL-3, 1985; Cosmos 1887, 1987) established that the ability of GH cells to release hormone, on return to earth, is compromised. The mechanism(s) responsible for this attenuation response is unknown. However, the data are sufficiently positive to indicate that the nature of the secretory defect resides directly within the GH cells.

  3. Identification of Proteins Related to Epigenetic Regulation in the Malignant Transformation of Aberrant Karyotypic Human Embryonic Stem Cells by Quantitative Proteomics

    PubMed Central

    Sun, Yi; Yang, Yixuan; Zeng, Sicong; Tan, Yueqiu; Lu, Guangxiu; Lin, Ge

    2014-01-01

    Previous reports have demonstrated that human embryonic stem cells (hESCs) tend to develop genomic alterations and progress to a malignant state during long-term in vitro culture. This raises concerns of the clinical safety in using cultured hESCs. However, transformed hESCs might serve as an excellent model to determine the process of embryonic stem cell transition. In this study, ITRAQ-based tandem mass spectrometry was used to quantify normal and aberrant karyotypic hESCs proteins from simple to more complex karyotypic abnormalities. We identified and quantified 2583 proteins, and found that the expression levels of 316 proteins that represented at least 23 functional molecular groups were significantly different in both normal and abnormal hESCs. Dysregulated protein expression in epigenetic regulation was further verified in six pairs of hESC lines in early and late passage. In summary, this study is the first large-scale quantitative proteomic analysis of the malignant transformation of aberrant karyotypic hESCs. The data generated should serve as a useful reference of stem cell-derived tumor progression. Increased expression of both HDAC2 and CTNNB1 are detected as early as the pre-neoplastic stage, and might serve as prognostic markers in the malignant transformation of hESCs. PMID:24465727

  4. Aberrant activation of the androgen receptor by NF-kappaB2/p52 in prostate cancer cells.

    PubMed

    Nadiminty, Nagalakshmi; Lou, Wei; Sun, Meng; Chen, Jun; Yue, Jiao; Kung, Hsing-Jien; Evans, Christopher P; Zhou, Qinghua; Gao, Allen C

    2010-04-15

    Prostate cancer initiation and progression are uniquely dependent on the androgen receptor (AR). Even when the cancer progresses to a castration-resistant stage, AR signaling remains active via a variety of mechanisms. In the present study, we showed that NF-kappaB/p52 can activate the AR, resulting in increased transactivation of AR-responsive genes, such as PSA and NKX3.1, in a ligand-independent manner. NF-kappaB2/p52 enhances nuclear translocation and activation of AR by interacting with its NH(2)-terminal domain and enhances the recruitment of coactivators such as p300 to the promoters of AR-dependent genes. These results were confirmed in three different prostate cancer cell lines: LAPC-4 (wild-type AR), LNCaP (mutant AR), and C4-2 (castration resistant). Transfection of p52 into LAPC-4 and LNCaP cells (which express low levels of p52) showed increased activation of the endogenous AR. Downregulation of endogenous p52 in C4-2 cells resulted in abrogation of AR constitutive activation. Comparison of the relative effects of p52 and p65 (RelA) showed that p52, but not p65, could activate the AR. Collectively, these findings, together with previous reports that the levels of NF-kappaB2/p52 are elevated in prostate cancer cells and that active NF-kappaB2/p52 promotes prostate cancer cell growth in vitro and in vivo, suggest that NF-kappaB2/p52 may play a critical role in the progression of castration-resistant prostate cancer.

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

    SciTech Connect

    Liu, Tongxin; Li, Qi; Sun, Quanquan; Zhang, Yuqin; Yang, Hua; Wang, Rong; Chen, Longhua; Wang, Wei

    2014-06-20

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

  6. Determination of genotoxic effects of Imazethapyr herbicide in Allium cepa root cells by mitotic activity, chromosome aberration, and comet assay.

    PubMed

    Liman, Recep; Ciğerci, İbrahim Hakkı; Öztürk, Nur Serap

    2015-02-01

    Imazethapyr (IM) is an imidazolinone herbicide that is currently used for broad-spectrum weed control in soybean and other legume crops. In this study, cytotoxic and genotoxic effects of IM were investigated by using mitotic index (MI), mitotic phases, chromosomal abnormalities (CAs) and DNA damage on the root meristem cells of Allium cepa. In Allium root growth inhibition test, EC50 value was determined as 20 ppm, and 0.5xEC50, EC50 and 2xEC50 concentrations of IM herbicide were introduced to onion tuber roots. Distilled water and methyl methane sulfonate (MMS, 10 mg/L) were used as a negative and positive control, respectively. As A. cepa cell cycle is 24 hours, so, application process was carried out for 24, 48, 72 and 96 hours. All the applied doses decreased MIs compared to control group and these declines were found to be statistically meaningful. Analysis of the chromosomes showed that 10 ppm IM except for 48 h induced CAs but 40 ppm IM except for 72 h decreased CAs. DNA damage was found significantly higher in 20 and 40 ppm of IM compared to the control in comet assay. These results indicated that IM herbicide exhibits cytotoxic activity but not genotoxic activity (except 10 ppm) and induced DNA damage in a dose dependent manner in A. cepa root meristematic cells. PMID:25752428

  7. Functional annotation of rare gene aberration drivers of pancreatic cancer.

    PubMed

    Tsang, Yiu Huen; Dogruluk, Turgut; Tedeschi, Philip M; Wardwell-Ozgo, Joanna; Lu, Hengyu; Espitia, Maribel; Nair, Nikitha; Minelli, Rosalba; Chong, Zechen; Chen, Fengju; Chang, Qing Edward; Dennison, Jennifer B; Dogruluk, Armel; Li, Min; Ying, Haoqiang; Bertino, Joseph R; Gingras, Marie-Claude; Ittmann, Michael; Kerrigan, John; Chen, Ken; Creighton, Chad J; Eterovic, Karina; Mills, Gordon B; Scott, Kenneth L

    2016-01-01

    As we enter the era of precision medicine, characterization of cancer genomes will directly influence therapeutic decisions in the clinic. Here we describe a platform enabling functionalization of rare gene mutations through their high-throughput construction, molecular barcoding and delivery to cancer models for in vivo tumour driver screens. We apply these technologies to identify oncogenic drivers of pancreatic ductal adenocarcinoma (PDAC). This approach reveals oncogenic activity for rare gene aberrations in genes including NAD Kinase (NADK), which regulates NADP(H) homeostasis and cellular redox state. We further validate mutant NADK, whose expression provides gain-of-function enzymatic activity leading to a reduction in cellular reactive oxygen species and tumorigenesis, and show that depletion of wild-type NADK in PDAC cell lines attenuates cancer cell growth in vitro and in vivo. These data indicate that annotating rare aberrations can reveal important cancer signalling pathways representing additional therapeutic targets. PMID:26806015

  8. Functional annotation of rare gene aberration drivers of pancreatic cancer

    PubMed Central

    Tsang, Yiu Huen; Dogruluk, Turgut; Tedeschi, Philip M.; Wardwell-Ozgo, Joanna; Lu, Hengyu; Espitia, Maribel; Nair, Nikitha; Minelli, Rosalba; Chong, Zechen; Chen, Fengju; Chang, Qing Edward; Dennison, Jennifer B.; Dogruluk, Armel; Li, Min; Ying, Haoqiang; Bertino, Joseph R.; Gingras, Marie-Claude; Ittmann, Michael; Kerrigan, John; Chen, Ken; Creighton, Chad J.; Eterovic, Karina; Mills, Gordon B.; Scott, Kenneth L.

    2016-01-01

    As we enter the era of precision medicine, characterization of cancer genomes will directly influence therapeutic decisions in the clinic. Here we describe a platform enabling functionalization of rare gene mutations through their high-throughput construction, molecular barcoding and delivery to cancer models for in vivo tumour driver screens. We apply these technologies to identify oncogenic drivers of pancreatic ductal adenocarcinoma (PDAC). This approach reveals oncogenic activity for rare gene aberrations in genes including NAD Kinase (NADK), which regulates NADP(H) homeostasis and cellular redox state. We further validate mutant NADK, whose expression provides gain-of-function enzymatic activity leading to a reduction in cellular reactive oxygen species and tumorigenesis, and show that depletion of wild-type NADK in PDAC cell lines attenuates cancer cell growth in vitro and in vivo. These data indicate that annotating rare aberrations can reveal important cancer signalling pathways representing additional therapeutic targets. PMID:26806015

  9. Metabolism, cell growth and the bacterial cell cycle.

    PubMed

    Wang, Jue D; Levin, Petra A

    2009-11-01

    Adaptation to fluctuations in nutrient availability is a fact of life for single-celled organisms in the 'wild'. A decade ago our understanding of how bacteria adjust cell cycle parameters to accommodate changes in nutrient availability stemmed almost entirely from elegant physiological studies completed in the 1960s. In this Opinion article we summarize recent groundbreaking work in this area and discuss potential mechanisms by which nutrient availability and metabolic status are coordinated with cell growth, chromosome replication and cell division.

  10. Bone Marrow-Derived Endothelial Progenitor Cells Protect Against Scopolamine-Induced Alzheimer-Like Pathological Aberrations.

    PubMed

    Safar, Marwa M; Arab, Hany H; Rizk, Sherine M; El-Maraghy, Shohda A

    2016-04-01

    Vascular endothelial dysfunction plays a key role in the pathogenesis of Alzheimer's disease (AD). Patients with AD have displayed decreased circulating endothelial progenitor cells (EPCs) which repair and maintain the endothelial function. Transplantation of EPCs has emerged as a promising approach for the management of cerebrovascular diseases including ischemic stroke, however, its impact on AD has been poorly described. Thus, the current study aimed at investigating the effects of bone marrow-derived (BM) EPCs transplantation in repeated scopolamine-induced cognitive impairment, an experimental model that replicates biomarkers of AD. Intravenously transplanted BM-EPCs migrated into the brain of rats and improved the learning and memory deficits. Meanwhile, they mitigated the deposition of amyloid plaques and associated histopathological alterations. At the molecular levels, BM-EPCs blunted the increase of hippocampal amyloid beta protein (Aβ), amyloid precursor protein (APP) and reinstated the Aβ-degrading neprilysin together with downregulation of p-tau and its upstream glycogen synthase kinase-3β (GSK-3β). They also corrected the perturbations of neurotransmitter levels including restoration of acetylcholine and associated esterase along with dopamine, GABA, and the neuroexitatory glutamate. Furthermore, BM-EPCs induced behavioral recovery via boosting of vascular endothelial growth factor (VEGF), nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and its upstream cAMP response element binding (CREB), suppression of the proinflammatory tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), and upregulation of interleukin-10 (IL-10). BM-EPCs also augmented Nrf2 and seladin-1. Generally, these actions were analogous to those exerted by adipose tissue-derived mesenchymal stem cells (AT-MSCs) and the reference anti-Alzheimer donepezil. For the first time, these findings highlight the beneficial actions of BM-EPCs against the memory

  11. Vibration Induces BAFF Overexpression and Aberrant O-Glycosylation of IgA1 in Cultured Human Tonsillar Mononuclear Cells in IgA Nephropathy

    PubMed Central

    Ye, Muyao; Liu, Chan; Yan, Wenzhe; Peng, Xiaofei; He, Liyu; Liu, Hong; Liu, Fuyou

    2016-01-01

    Objective. To investigate the influence of in vitro vibratory stimulation of human tonsillar mononuclear cells (TMCs). Methods. Fourteen IgA nephropathy (IgAN) patients with chronic tonsillitis (CT) and 12 CT patients with no renal pathology were enrolled. Group A TMCs were collected after 24 hours of culture and used to determine baseline levels. TMCs in groups B, C, D, E, and F were exposed to vibratory stimulation (60 Hz) for 0 (as the control group), 1, 3, 5, and 10 minutes, respectively. Results. Baseline concentrations of B-cell-activation factor (BAFF) and IgA1, BAFF mRNA expression, and aberrant O-glycosylation IgA1 level were higher in the IgAN group as compared to that in the CT group, and all increased after vibratory stimulation. Baseline mRNA expressions of core β1,3-galactosyltransferase (C1GALT1) and core β1,3GalT-specific molecular chaperone (Cosmc) were lower in the IgAN group; the levels decreased further after vibratory stimulation. Conclusion. In patients with IgAN, vibratory stimulation of TMCs appears to induce IgA1 secretion through activation of BAFF release and to aberrant O-glycosylation IgA1 by suppressing C1GALT1 and Cosmc expression. In vitro vibratory stimulation of human TMCs mimics the vibratory simulation of palatine tonsils produced by vocal cords during phonation.

  12. Vibration Induces BAFF Overexpression and Aberrant O-Glycosylation of IgA1 in Cultured Human Tonsillar Mononuclear Cells in IgA Nephropathy

    PubMed Central

    Ye, Muyao; Liu, Chan; Yan, Wenzhe; Peng, Xiaofei; He, Liyu; Liu, Hong; Liu, Fuyou

    2016-01-01

    Objective. To investigate the influence of in vitro vibratory stimulation of human tonsillar mononuclear cells (TMCs). Methods. Fourteen IgA nephropathy (IgAN) patients with chronic tonsillitis (CT) and 12 CT patients with no renal pathology were enrolled. Group A TMCs were collected after 24 hours of culture and used to determine baseline levels. TMCs in groups B, C, D, E, and F were exposed to vibratory stimulation (60 Hz) for 0 (as the control group), 1, 3, 5, and 10 minutes, respectively. Results. Baseline concentrations of B-cell-activation factor (BAFF) and IgA1, BAFF mRNA expression, and aberrant O-glycosylation IgA1 level were higher in the IgAN group as compared to that in the CT group, and all increased after vibratory stimulation. Baseline mRNA expressions of core β1,3-galactosyltransferase (C1GALT1) and core β1,3GalT-specific molecular chaperone (Cosmc) were lower in the IgAN group; the levels decreased further after vibratory stimulation. Conclusion. In patients with IgAN, vibratory stimulation of TMCs appears to induce IgA1 secretion through activation of BAFF release and to aberrant O-glycosylation IgA1 by suppressing C1GALT1 and Cosmc expression. In vitro vibratory stimulation of human TMCs mimics the vibratory simulation of palatine tonsils produced by vocal cords during phonation. PMID:27672662

  13. Aberrant cell divisions in root meristeme of maize following exposure to X-rays low doses compared to similar effects of 50 Hz electromagnetic exposure

    NASA Astrophysics Data System (ADS)

    Focea, R.; Capraru, G.; Racuciu, M.; Creanga, D.; Luchian, T.

    2012-04-01

    The response of maize to radiation exposure was investigated by two cytogenetic methods considering the importance of the geno-toxic effect for environmental and agricultural purposes. Uniform genophond seeds, freshly germinated, were exposed to relatively low radiation doses using a radiotherapy X-ray applicator from a hospital irradiation device and to a 50 Hz electromagnetic field with about 10 mT magnetic induction (generated within laboratory assembled electromagnetic coils). Radicular meristeme tissue aliquots were prevailed for cytogenetic investigation based on microscopic observations and cell counting. Microscope slides were prepared following a specific procedure (squash technique and Feulgen method based on modified Carr reactive coloration). Mitotic index as well as chromosomal aberration percentage were calculated for more than 30,000 cells taken into account. From a qualitative viewpoint, chromosomal aberrations such as interchromatidian bridges, lagging and expelled chromosomes and multipolar divisions were evidenced - no distinct situation for either ionizing radiation or electromagnetic field being identified. The main quantitative difference consisted in the increased mitotic index for electromagnetic exposure increased times compared with the diminished mitotic index in the case of low X-ray doses.

  14. Chromosome aberrations in decondensed sperm DNA

    SciTech Connect

    Preston, R.J.

    1982-01-01

    Factors that could influence the chromosomal aberration frequency observed at first cleavage following in vivo exposure of germ cells to chemical mutagens are discussed. The techniques of chromosome aberration analysis following sperm DNA condensation by in vitro fertilization or fusion seem to be viable research areas for providing information of human germ cell exposures. However, the potential sensitivity of the assay needs to be better understood, and factors that can influence this sensitivity require a great deal of further study using animal models.

  15. Polarity, cell division, and out-of-equilibrium dynamics control the growth of epithelial structures

    PubMed Central

    Cerruti, Benedetta; Puliafito, Alberto; Shewan, Annette M.; Yu, Wei; Combes, Alexander N.; Little, Melissa H.; Chianale, Federica; Primo, Luca; Serini, Guido; Mostov, Keith E.; Celani, Antonio

    2013-01-01

    The growth of a well-formed epithelial structure is governed by mechanical constraints, cellular apico-basal polarity, and spatially controlled cell division. Here we compared the predictions of a mathematical model of epithelial growth with the morphological analysis of 3D epithelial structures. In both in vitro cyst models and in developing epithelial structures in vivo, epithelial growth could take place close to or far from mechanical equilibrium, and was determined by the hierarchy of time-scales of cell division, cell–cell rearrangements, and lumen dynamics. Equilibrium properties could be inferred by the analysis of cell–cell contact topologies, and the nonequilibrium phenotype was altered by inhibiting ROCK activity. The occurrence of an aberrant multilumen phenotype was linked to fast nonequilibrium growth, even when geometric control of cell division was correctly enforced. We predicted and verified experimentally that slowing down cell division partially rescued a multilumen phenotype induced by altered polarity. These results improve our understanding of the development of epithelial organs and, ultimately, of carcinogenesis. PMID:24145168

  16. Chromosome segregation impacts on cell growth and division site selection in Corynebacterium glutamicum.

    PubMed

    Donovan, Catriona; Schauss, Astrid; Krämer, Reinhard; Bramkamp, Marc

    2013-01-01

    Spatial and temporal regulation of bacterial cell division is imperative for the production of viable offspring. In many rod-shaped bacteria, regulatory systems such as the Min system and nucleoid occlusion ensure the high fidelity of midcell divisome positioning. However, regulation of division site selection in bacteria lacking recognizable Min and nucleoid occlusion remains less well understood. Here, we describe one such rod-shaped organism, Corynebacterium glutamicum, which does not always place the division septum precisely at midcell. Here we now show at single cell level that cell growth and division site selection are spatially and temporally regulated by chromosome segregation. Mutants defective in chromosome segregation have more variable cell growth and aberrant placement of the division site. In these mutants, division septa constrict over and often guillotine the nucleoid, leading to nonviable, DNA-free cells. Our results suggest that chromosome segregation or some nucleoid associated factor influences growth and division site selection in C. glutamicum. Understanding growth and regulation of C. glutamicum cells will also be of importance to develop strains for industrial production of biomolecules, such as amino acids.

  17. Chick eyes compensate for chromatic simulations of hyperopic and myopic defocus: evidence that the eye uses longitudinal chromatic aberration to guide eye-growth.

    PubMed

    Rucker, Frances J; Wallman, Josh

    2009-07-01

    Longitudinal chromatic aberration (LCA) causes short wavelengths to be focused in front of long wavelengths. This chromatic signal is evidently used to guide ocular accommodation. We asked whether chick eyes exposed to static gratings simulating the chromatic effects of myopic or hyperopic defocus would "compensate" for the simulated defocus. We alternately exposed one eye of each chick to a sine-wave grating (5 or 2 cycle/deg) simulating myopic defocus ("MY defocus": image focused in front of retina; hence, red contrast higher than blue) and the other eye to a grating of the same spatial frequency simulating hyperopic defocus ("HY defocus": blue contrast higher than red). The chicks were placed in a drum with one eye covered with one grating, and then switched to another drum with the other grating with the other eye covered. To minimize the effects of altered eye-growth on image contrast, we studied only the earliest responses: first, we measured changes in choroidal thickness 45 min to 1 h after one 15-min episode in the drum, then we measured glycosaminoglycans (GAG) synthesis in sclera and choroid (by the incorporation of labeled sulfate in tissue culture) after a day of four 30-min episodes in the drum. The eyes compensated in the appropriate directions: The choroids of the eyes exposed to the HY simulation showed significantly more thinning (less thickening) over the course of the experiment than the choroids of the eyes exposed to the MY simulation (all groups mean:-17 microm; 5 c/d groups: -24 microm; paired t-test (one-tailed): p=0.0006). The rate of scleral GAG synthesis in the eye exposed to the HY simulation was significantly greater than in the eye exposed to the MY simulation (HY/MY ratio=1.20; one sample t-test (one-tailed): p=0.015). There was no significant interaction between the sign of the simulated defocus and either the spatial frequency or the presence of a +3 D lens used to compensate for the 33 cm distance of the drum. Although previous

  18. Aberrant methylation of LINE-1, SLIT2, MAL and IGFBP7 in non-small cell lung cancer.

    PubMed

    Suzuki, Makoto; Shiraishi, Kenji; Eguchi, Ayami; Ikeda, Koei; Mori, Takeshi; Yoshimoto, Kentaro; Ohba, Yasuomi; Yamada, Tatsuya; Ito, Takaaki; Baba, Yoshifumi; Baba, Hideo

    2013-04-01

    Genome-wide DNA hypomethylation and gene hypermethylation play important roles in instability and carcino-genesis. Methylation in long interspersed nucleotide element 1 (LINE-1) is a good indicator of the global DNA methylation level within a cell. Slit homolog 2 (SLIT2), myelin and lymphocyte protein gene (MAL) and insulin-like growth factor binding protein 7 (IGFBP7) are known to be hypermethylated in various malignancies. The aim of the present study was to assess the precise methylation levels of LINE-1, SLIT2, MAL and IGFBP7 in non-small cell lung cancer (NSCLC) using a pyrosequencing assay. Methylation of all regions was examined in 56 primary NSCLCs using a pyrosequencing assay. Changes in mRNA expression levels of SLIT2, MAL and IGFBP7 were measured before and after treatment with a demethylating agent. Methylation of these genes was also examined in 9 lung cancer cell lines using RT-PCR and a pyrosequencing assay. Frequencies of hypomethylation of LINE-1 and hypermethylation of SLIT2, MAL and IGFBP7, defined by predetermined cut off values, were 55, 64, 46 and 54% in NSCLCs, respectively and exhibited tumor-specific features. The hypermethylation of all genes was well correlated with changes in expression. The methylation level and frequency of MAL were significantly higher in smokers and in patients without EGFR mutations. Through accurate measurement of methylation levels using pyrosequencing, hypomethylation of LINE-1 and hypermethylation of SLIT2, MAL and IGFBP7 were frequently detected in NSCLCs and associated with various clinical features. Analysis of the methylation profiles of these genes may, therefore, provide novel opportunities for the therapy of NSCLCs.

  19. Triiodothyronine regulates cell growth and survival in renal cell cancer.

    PubMed

    Czarnecka, Anna M; Matak, Damian; Szymanski, Lukasz; Czarnecka, Karolina H; Lewicki, Slawomir; Zdanowski, Robert; Brzezianska-Lasota, Ewa; Szczylik, Cezary

    2016-10-01

    Triiodothyronine plays an important role in the regulation of kidney cell growth, differentiation and metabolism. Patients with renal cell cancer who develop hypothyreosis during tyrosine kinase inhibitor (TKI) treatment have statistically longer survival. In this study, we developed cell based model of triiodothyronine (T3) analysis in RCC and we show the different effects of T3 on renal cell cancer (RCC) cell growth response and expression of the thyroid hormone receptor in human renal cell cancer cell lines from primary and metastatic tumors along with human kidney cancer stem cells. Wild-type thyroid hormone receptor is ubiquitously expressed in human renal cancer cell lines, but normalized against healthy renal proximal tube cell expression its level is upregulated in Caki-2, RCC6, SKRC-42, SKRC-45 cell lines. On the contrary the mRNA level in the 769-P, ACHN, HKCSC, and HEK293 cells is significantly decreased. The TRβ protein was abundant in the cytoplasm of the 786-O, Caki-2, RCC6, and SKRC-45 cells and in the nucleus of SKRC-42, ACHN, 769-P and cancer stem cells. T3 has promoting effect on the cell proliferation of HKCSC, Caki-2, ASE, ACHN, SK-RC-42, SMKT-R2, Caki-1, 786-0, and SK-RC-45 cells. Tyrosine kinase inhibitor, sunitinib, directly inhibits proliferation of RCC cells, while thyroid hormone receptor antagonist 1-850 (CAS 251310‑57-3) has less significant inhibitory impact. T3 stimulation does not abrogate inhibitory effect of sunitinib. Renal cancer tumor cells hypostimulated with T3 may be more responsive to tyrosine kinase inhibition. Moreover, some tumors may be considered as T3-independent and present aggressive phenotype with thyroid hormone receptor activated independently from the ligand. On the contrary proliferation induced by deregulated VHL and or c-Met pathways may transgress normal T3 mediated regulation of the cell cycle. PMID:27632932

  20. Testing for oncogenic molecular aberrations in cell-free DNA-based liquid biopsies in the clinic: are we there yet?

    PubMed

    Polivka, Jiri; Pesta, Martin; Janku, Filip

    2015-01-01

    The optimal choice of cancer therapy depends upon analysis of the tumor genome for druggable molecular alterations. The spatial and temporal intratumor heterogeneity of cancers creates substantial challenges, as molecular profile depends on time and site of tumor tissue collection. To capture the entire molecular profile, multiple biopsies from primary and metastatic sites at different time points would be required, which is not feasible for ethical or economic reasons. Molecular analysis of circulating cell-free DNA offers a novel, minimally invasive method that can be performed at multiple time-points and plausibly better represents the prevailing molecular profile of the cancer. Molecular analysis of this cell-free DNA offers multiple clinically useful applications, such as identification of molecular targets for cancer therapy, monitoring of tumor molecular profile in real time, detection of emerging molecular aberrations associated with resistance to particular therapy, determination of cancer prognosis and diagnosis of cancer recurrence or progression.

  1. Barth Syndrome: From Mitochondrial Dysfunctions Associated with Aberrant Production of Reactive Oxygen Species to Pluripotent Stem Cell Studies

    PubMed Central

    Saric, Ana; Andreau, Karine; Armand, Anne-Sophie; Møller, Ian M.; Petit, Patrice X.

    2016-01-01

    Mutations in the gene encoding the enzyme tafazzin, TAZ, cause Barth syndrome (BTHS). Individuals with this X-linked multisystem disorder present cardiomyopathy (CM) (often dilated), skeletal muscle weakness, neutropenia, growth retardation, and 3-methylglutaconic aciduria. Biopsies of the heart, liver and skeletal muscle of patients have revealed mitochondrial malformations and dysfunctions. It is the purpose of this review to summarize recent results of studies on various animal or cell models of Barth syndrome, which have characterized biochemically the strong cellular defects associated with TAZ mutations. Tafazzin is a mitochondrial phospholipidlysophospholipid transacylase that shuttles acyl groups between phospholipids and regulates the remodeling of cardiolipin (CL), a unique inner mitochondrial membrane phospholipid dimer consisting of two phosphatidyl residues linked by a glycerol bridge. After their biosynthesis, the acyl chains of CLs may be modified in remodeling processes involving up to three different enzymes. Their characteristic acyl chain composition depends on the function of tafazzin, although the enzyme itself surprisingly lacks acyl specificity. CLs are crucial for correct mitochondrial structure and function. In addition to their function in the basic mitochondrial function of ATP production, CLs play essential roles in cardiac function, apoptosis, autophagy, cell cycle regulation and Fe-S cluster biosynthesis. Recent developments in tafazzin research have provided strong insights into the link between mitochondrial dysfunction and the production of reactive oxygen species (ROS). An important tool has been the generation of BTHS-specific induced pluripotent stem cells (iPSCs) from BTHS patients. In a complementary approach, disease-specific mutations have been introduced into wild-type iPSC lines enabling direct comparison with isogenic controls. iPSC-derived cardiomyocytes were then characterized using biochemical and classical bioenergetic

  2. Pleiotropic Roles of Polyglycerolphosphate Synthase of Lipoteichoic Acid in Growth of Staphylococcus aureus Cells ▿ †

    PubMed Central

    Oku, Yusuke; Kurokawa, Kenji; Matsuo, Miki; Yamada, Sakuo; Lee, Bok-Luel; Sekimizu, Kazuhisa

    2009-01-01

    Lipoteichoic acid (LTA) is one of two anionic polymers on the surface of the gram-positive bacterium Staphylococcus aureus. LTA is critical for the bacterium-host cell interaction and has recently been shown to be required for cell growth and division. To determine additional biological roles of LTA, we found it necessary to identify permissive conditions for the growth of an LTA-deficient mutant. We found that an LTA-deficient S. aureus ΔltaS mutant could grow at 30°C but not at 37°C. Even at the permissive temperature, ΔltaS mutant cells had aberrant cell division and separation, decreased autolysis, and reduced levels of peptidoglycan hydrolases. Upshift of ΔltaS mutant cells to a nonpermissive temperature caused an inability to exclude Sytox green dye. A high-osmolarity growth medium remarkably rescued the colony-forming ability of the ΔltaS mutant at 37°C, indicating that LTA synthesis is required for growth under low-osmolarity conditions. In addition, the ΔltaS mutation was found to be synthetically lethal with the ΔtagO mutation, which disrupts the synthesis of the other anionic polymer, wall teichoic acid (WTA), at 30°C, suggesting that LTA and WTA compensate for one another in an essential function. PMID:18952789

  3. Overexpression of SlUPA-like induces cell enlargement, aberrant development and low stress tolerance through phytohormonal pathway in tomato.

    PubMed

    Cui, Baolu; Hu, Zongli; Hu, Jingtao; Zhang, Yanjie; Yin, Wencheng; Zhu, Zhiguo; Feng, Ye; Chen, Guoping

    2016-01-01

    upa20 induces cell enlargement and hypertrophy development. In our research, overexpression of SlUPA-like, orthologous to upa20, severely affected the growth of vegetative and reproductive tissues. Wilted leaves curled upwardly and sterile flowers were found in transgenic lines. Through anatomical analysis, palisade and spongy tissues showed fluffy and hypertrophic development in transgenic plants. Gene expression analysis showed that GA responsive, biosynthetic and signal transduction genes (e.g. GAST1, SlGA20OXs, SlGA3OXs, SlGID1s, and SlPREs) were significantly upregulated, indicating that GA response is stimulated by overproduction of SlUPA-like. Furthermore, SlUPA-like was strongly induced by exogenous JA and wounding. Decreased expression of PI-I and induced expression of SlJAZs (including SlJAZ2, SlJAZ10 and SlJAZ11) were observed in transgenic plants, suggesting that JA response is repressed. In addition, SlUPA-like overexpressed plant exhibited more opened stoma and higher water loss than the control when treated with dehydration stress, which was related to decreased ABA biosynthesis, signal transduction and response. Particularly, abnormal developments of transgenic plants promote the plant susceptibility to Xanthomonas campestris pv. campestris. Therefore, it is deduced from these results that SlUPA-like plays vital role in regulation of plant development and stress tolerance through GA, JA and ABA pathways. PMID:27025226

  4. Overexpression of SlUPA-like induces cell enlargement, aberrant development and low stress tolerance through phytohormonal pathway in tomato

    PubMed Central

    Cui, Baolu; Hu, Zongli; Hu, Jingtao; Zhang, Yanjie; Yin, Wencheng; Zhu, Zhiguo; Feng, Ye; Chen, Guoping

    2016-01-01

    upa20 induces cell enlargement and hypertrophy development. In our research, overexpression of SlUPA-like, orthologous to upa20, severely affected the growth of vegetative and reproductive tissues. Wilted leaves curled upwardly and sterile flowers were found in transgenic lines. Through anatomical analysis, palisade and spongy tissues showed fluffy and hypertrophic development in transgenic plants. Gene expression analysis showed that GA responsive, biosynthetic and signal transduction genes (e.g. GAST1, SlGA20OXs, SlGA3OXs, SlGID1s, and SlPREs) were significantly upregulated, indicating that GA response is stimulated by overproduction of SlUPA-like. Furthermore, SlUPA-like was strongly induced by exogenous JA and wounding. Decreased expression of PI-I and induced expression of SlJAZs (including SlJAZ2, SlJAZ10 and SlJAZ11) were observed in transgenic plants, suggesting that JA response is repressed. In addition, SlUPA-like overexpressed plant exhibited more opened stoma and higher water loss than the control when treated with dehydration stress, which was related to decreased ABA biosynthesis, signal transduction and response. Particularly, abnormal developments of transgenic plants promote the plant susceptibility to Xanthomonas campestris pv. campestris. Therefore, it is deduced from these results that SlUPA-like plays vital role in regulation of plant development and stress tolerance through GA, JA and ABA pathways. PMID:27025226

  5. A synthetic lethal screen identifies SLK1, a novel protein kinase homolog implicated in yeast cell morphogenesis and cell growth.

    PubMed Central

    Costigan, C; Gehrung, S; Snyder, M

    1992-01-01

    The Saccharomyces cerevisiae SPA2 protein localizes at sites involved in polarized cell growth in budding cells and mating cells. spa2 mutants have defects in projection formation during mating but are healthy during vegetative growth. A synthetic lethal screen was devised to identify mutants that require the SPA2 gene for vegetative growth. One mutant, called slk-1 (for synthetic lethal kinase), has been characterized extensively. The SLK1 gene has been cloned, and sequence analysis predicts that the SLK1 protein is 1,478 amino acid residues in length. Approximately 300 amino acids at the carboxy terminus exhibit sequence similarity with the catalytic domains of protein kinases. Disruption mutations have been constructed in the SLK1 gene. slk1 null mutants cannot grow at 37 degrees C, but many cells can grow at 30, 24, and 17 degrees C. Dead slk1 mutant cells usually have aberrant cell morphologies, and many cells are very small, approximately one-half the diameter of wild-type cells. Surviving slk1 cells also exhibit morphogenic defects; these cells are impaired in their ability to form projections upon exposure to mating pheromones. During vegetative growth, a higher fraction of slk1 cells are unbudded compared with wild-type cells, and under nutrient limiting conditions, slk1 cells exhibit defects in cell cycle arrest. The different slk1 mutant defects are partially rescued by an extra copy of the SSD1/SRK1 gene. SSD1/SRK1 has been independently isolated as a suppressor of mutations in genes involved in growth control, sit4, pde2, bcy1, and ins1 (A. Sutton, D. Immanuel, and K.T. Arnat, Mol. Cell. Biol. 11:2133-2148, 1991; R.B. Wilson, A.A. Brenner, T.B. White, M.J. Engler, J.P. Gaughran, and K. Tatchell, Mol. Cell. Biol. 11:3369-3373, 1991). These data suggest that SLK1 plays a role in both cell morphogenesis and the control of cell growth. We speculate that SLK1 may be a regulatory link for these two cellular processes. Images PMID:1545797

  6. The Silencing of CCND2 by Promoter Aberrant Methylation in Renal Cell Cancer and Analysis of the Correlation between CCND2 Methylation Status and Clinical Features

    PubMed Central

    Wang, Lu; Cui, Yun; Zhang, Lian; Sheng, Jindong; Yang, Yang; Kuang, Guanyu; Fan, Yu; Zhang, Qian; Jin, Jie

    2016-01-01

    Cyclin D2 (CCND2) is a member of the D-type cyclins, which plays a pivotal role in cell cycle regulation, differentiation and malignant transformation. However, its expression status and relative regulation mechanism remains unclear in renal cell cancer (RCC). In our study, the mRNA expression level of CCND2 is down-regulated in 22/23 paired RCC tissues (p<0.05). In addition, its protein expression level is also decreased in 43/43 RCC tumor tissues compared with its corresponding non-malignant tissues (p<0.001). We further detected that CCND2 was down-regulated or silenced in 6/7 RCC cell lines, but expressed in “normal” human proximal tubular (HK-2) cell line. Subsequently, MSP and BGS results showed that the methylation status in CCND2 promoter region is closely associated with its expression level in RCC cell lines. Treatment with 5-Aza with or without TSA restored CCND2 expression in several methylated RCC cell lines. Among the 102 RCC tumors, methylation of CCND2 was detected in 29/102 (28%) cases. Only 2/23 (8.7%) adjacent non-malignant tissues showed methylation. We then analyzed the correlation of clinical features and its promoter methylation. Collectively, our data suggested that loss of CCND2 expression is closely associated with the promoter aberrant methylation. PMID:27583477

  7. The Silencing of CCND2 by Promoter Aberrant Methylation in Renal Cell Cancer and Analysis of the Correlation between CCND2 Methylation Status and Clinical Features.

    PubMed

    Wang, Lu; Cui, Yun; Zhang, Lian; Sheng, Jindong; Yang, Yang; Kuang, Guanyu; Fan, Yu; Zhang, Qian; Jin, Jie

    2016-01-01

    Cyclin D2 (CCND2) is a member of the D-type cyclins, which plays a pivotal role in cell cycle regulation, differentiation and malignant transformation. However, its expression status and relative regulation mechanism remains unclear in renal cell cancer (RCC). In our study, the mRNA expression level of CCND2 is down-regulated in 22/23 paired RCC tissues (p<0.05). In addition, its protein expression level is also decreased in 43/43 RCC tumor tissues compared with its corresponding non-malignant tissues (p<0.001). We further detected that CCND2 was down-regulated or silenced in 6/7 RCC cell lines, but expressed in "normal" human proximal tubular (HK-2) cell line. Subsequently, MSP and BGS results showed that the methylation status in CCND2 promoter region is closely associated with its expression level in RCC cell lines. Treatment with 5-Aza with or without TSA restored CCND2 expression in several methylated RCC cell lines. Among the 102 RCC tumors, methylation of CCND2 was detected in 29/102 (28%) cases. Only 2/23 (8.7%) adjacent non-malignant tissues showed methylation. We then analyzed the correlation of clinical features and its promoter methylation. Collectively, our data suggested that loss of CCND2 expression is closely associated with the promoter aberrant methylation. PMID:27583477

  8. Budding yeast colony growth study based on circular granular cell

    NASA Astrophysics Data System (ADS)

    Aprianti, Devi; Khotimah, S. N.; Viridi, S.

    2016-08-01

    Yeast colony growth can be modelled by using circular granular cells, which can grow and produce buds. The bud growth angle can be set to regulate cell budding pattern. Cohesion force, contact force and Stokes force were adopted to accommodate the behaviour and interactions among cells. Simulation steps are divided into two steps, the explicit step is due to cell growing and implicit step for the cell rearrangement. Only in explicit step that time change was performed. In this study, we examine the influence of cell diameter growth time and reproduction time combination toward the growth of cell number and colony formation. We find a commutative relation between the cell diameter growth time and reproduction time to the specific growth rate. The greater value of the multiplication of the parameters, the smaller specific growth rate is obtained. It also shows a linear correlation between the specific growth rate and colony diameter growth rate.

  9. Mesenchymal stem cell like (MSCl) cells generated from human embryonic stem cells support pluripotent cell growth

    SciTech Connect

    Varga, Nora; Vereb, Zoltan; Rajnavoelgyi, Eva; Nemet, Katalin; Uher, Ferenc; Sarkadi, Balazs; Apati, Agota

    2011-10-28

    Highlights: Black-Right-Pointing-Pointer MSC like cells were derived from hESC by a simple and reproducible method. Black-Right-Pointing-Pointer Differentiation and immunosuppressive features of MSCl cells were similar to bmMSC. Black-Right-Pointing-Pointer MSCl cells as feeder cells support the undifferentiated growth of hESC. -- Abstract: Mesenchymal stem cell like (MSCl) cells were generated from human embryonic stem cells (hESC) through embryoid body formation, and isolated by adherence to plastic surface. MSCl cell lines could be propagated without changes in morphological or functional characteristics for more than 15 passages. These cells, as well as their fluorescent protein expressing stable derivatives, efficiently supported the growth of undifferentiated human embryonic stem cells as feeder cells. The MSCl cells did not express the embryonic (Oct4, Nanog, ABCG2, PODXL, or SSEA4), or hematopoietic (CD34, CD45, CD14, CD133, HLA-DR) stem cell markers, while were positive for the characteristic cell surface markers of MSCs (CD44, CD73, CD90, CD105). MSCl cells could be differentiated toward osteogenic, chondrogenic or adipogenic directions and exhibited significant inhibition of mitogen-activated lymphocyte proliferation, and thus presented immunosuppressive features. We suggest that cultured MSCl cells can properly model human MSCs and be applied as efficient feeders in hESC cultures.

  10. Olive Phenolics as c-Met Inhibitors: (-)-Oleocanthal Attenuates Cell Proliferation, Invasiveness, and Tumor Growth in Breast Cancer Models

    PubMed Central

    Akl, Mohamed R.; Ayoub, Nehad M.; Mohyeldin, Mohamed M.; Busnena, Belnaser A.; Foudah, Ahmed I.; Liu, Yong-Yu; Sayed, Khalid A. EI

    2014-01-01

    Dysregulation of the Hepatocyte growth factor (HGF)/c-Met signaling axis upregulates diverse tumor cell functions, including cell proliferation, survival, scattering and motility, epithelial-to-mesenchymal transition (EMT), angiogenesis, invasion, and metastasis. (-)-Oleocanthal is a naturally occurring secoiridoid from extra-virgin olive oil, which showed antiproliferative and antimigratory activity against different cancer cell lines. The aim of this study was to characterize the intracellular mechanisms involved in mediating the anticancer effects of (-)-oleocanthal treatment and the potential involvement of c-Met receptor signaling components in breast cancer. Results showed that (-)-oleocanthal inhibits the growth of human breast cancer cell lines MDA-MB-231, MCF-7 and BT-474 while similar treatment doses were found to have no effect on normal human MCF10A cell growth. In addition, (-)-oleocanthal treatment caused a dose-dependent inhibition of HGF-induced cell migration, invasion and G1/S cell cycle progression in breast cancer cell lines. Moreover, (-)-oleocanthal treatment effects were found to be mediated via inhibition of HGF-induced c-Met activation and its downstream mitogenic signaling pathways. This growth inhibitory effect is associated with blockade of EMT and reduction in cellular motility. Further results from in vivo studies showed that (-)-oleocanthal treatment suppressed tumor cell growth in an orthotopic model of breast cancer in athymic nude mice. Collectively, the findings of this study suggest that (-)-oleocanthal is a promising dietary supplement lead with potential for therapeutic use to control malignancies with aberrant c-Met activity. PMID:24849787

  11. Olive phenolics as c-Met inhibitors: (-)-Oleocanthal attenuates cell proliferation, invasiveness, and tumor growth in breast cancer models.

    PubMed

    Akl, Mohamed R; Ayoub, Nehad M; Mohyeldin, Mohamed M; Busnena, Belnaser A; Foudah, Ahmed I; Liu, Yong-Yu; Sayed, Khalid A Ei

    2014-01-01

    Dysregulation of the Hepatocyte growth factor (HGF)/c-Met signaling axis upregulates diverse tumor cell functions, including cell proliferation, survival, scattering and motility, epithelial-to-mesenchymal transition (EMT), angiogenesis, invasion, and metastasis. (-)-Oleocanthal is a naturally occurring secoiridoid from extra-virgin olive oil, which showed antiproliferative and antimigratory activity against different cancer cell lines. The aim of this study was to characterize the intracellular mechanisms involved in mediating the anticancer effects of (-)-oleocanthal treatment and the potential involvement of c-Met receptor signaling components in breast cancer. Results showed that (-)-oleocanthal inhibits the growth of human breast cancer cell lines MDA-MB-231, MCF-7 and BT-474 while similar treatment doses were found to have no effect on normal human MCF10A cell growth. In addition, (-)-oleocanthal treatment caused a dose-dependent inhibition of HGF-induced cell migration, invasion and G1/S cell cycle progression in breast cancer cell lines. Moreover, (-)-oleocanthal treatment effects were found to be mediated via inhibition of HGF-induced c-Met activation and its downstream mitogenic signaling pathways. This growth inhibitory effect is associated with blockade of EMT and reduction in cellular motility. Further results from in vivo studies showed that (-)-oleocanthal treatment suppressed tumor cell growth in an orthotopic model of breast cancer in athymic nude mice. Collectively, the findings of this study suggest that (-)-oleocanthal is a promising dietary supplement lead with potential for therapeutic use to control malignancies with aberrant c-Met activity. PMID:24849787

  12. Bone morphogenetic protein 2 inhibits the proliferation and growth of human colorectal cancer cells

    PubMed Central

    ZHANG, YUNYUAN; CHEN, XIAN; QIAO, MIN; ZHANG, BING-QIANG; WANG, NING; ZHANG, ZHONGLIN; LIAO, ZHAN; ZENG, LIYI; DENG, YOULIN; DENG, FANG; ZHANG, JUNHUI; YIN, LIANGJUN; LIU, WEI; ZHANG, QIAN; YAN, ZHENGJIAN; YE, JIXING; WANG, ZHONGLIANG; ZHOU, LAN; LUU, HUE H.; HAYDON, REX C.; HE, TONG-CHUAN; ZHANG, HONGYU

    2014-01-01

    Colorectal cancer (CRC) is one of the most deadly cancers worldwide. Significant progress has been made in understanding the molecular pathogenesis of CRC, which has led to successful early diagnosis, surgical intervention and combination chemotherapy. However, limited therapeutic options are available for metastatic and/or drug-resistant CRC. While the aberrantly activated Wnt/β-catenin pathway plays a critical initiating role in CRC development, disruption of the bone morphogenetic protein (BMP) pathway causes juvenile polyposis syndrome, suggesting that BMP signaling may play a role in CRC development. However, conflicting results have been reported concerning the possible roles of BMP signaling in sporadic colon cancer. Here, we investigated the effect of BMP2 on the proliferation, migration, invasiveness and tumor growth capability of human CRC cells. Using an adenovirus vector that overexpresses BMP2 and the piggyBac transposon-mediated stable BMP2 overexpression CRC line, we found that exogenous BMP2 effectively inhibited HCT116 cell proliferation and colony formation. BMP2 was shown to suppress colon cancer cell migration and invasiveness. Under a low serum culture condition, forced expression of BMP2 induced a significantly increased level of apoptosis in HCT116 cells. Using a xenograft tumor model, we found that forced expression of BMP2 in HCT116 cells suppressed tumor growth, accompanied by decreased cell proliferation activity. Taken together, our results strongly suggest that BMP2 plays an important inhibitory role in governing the proliferation and aggressive features of human CRC cells. PMID:24993644

  13. Aberrant apoptotic machinery confers melanoma dual resistance to BRAFV600E inhibitor and immune effector cells: immunosensitization by a histone deacetylase inhibitor

    PubMed Central

    Jazirehi, Ali R; Nazarian, Ramin; Torres-Collado, Antoni Xavier; Economou, James S

    2014-01-01

    BRAFV600E-inhibitors (BRAFi; e.g., vemurafenib) and modern immune-based therapies such as PD-1/PD-L1 and CTLA-4 checkpoints blockade and adoptive cell transfer (ACT) have significantly improved the care of melanoma patients. Having these two effective (BRAFi and immunotherapy) therapies raises the question whether there is a rational biological basis for using them in combination. We developed an in vitro model to determine whether tumor resistance mechanisms to a small molecule inhibitor of a driver oncogene, and to cytotoxic T lymphocyte (CTL)- and natural killer (NK) cell-delivered apoptotic death signals were exclusive or intersecting. We generated melanoma sublines resistant to BRAFi vemurafenib and to CTL recognizing the MART-1 melanoma antigen. Vemurafenib-resistant (VemR) sublines were cross-resistant to MART CTL and NK cells indicating that a common apoptotic pathway governing tumor response to both modalities was disrupted. Pretreatment of VemR melanomas with a histone deacetylase inhibitor (HDACi) restored sensitivity to MART CTL and NK apoptosis by skewing the apoptotic gene programs towards a proapoptotic phenotype. Our in vitro findings suggest that during the course of acquisition of BRAFi resistance, melanomas develop cross-resistance to CTL- and NK-killing. Further, aberrant apoptotic pathways, amenable by an FDA-approved chromatin remodeling drug, regulate tumor resistance mechanisms to immune effector cells. These results may provide rational molecular basis for further investigations to combine these therapies clinically. PMID:24660121

  14. Genome-wide analysis of aberrant methylation in human breast cancer cells using methyl-DNA immunoprecipitation combined with high-throughput sequencing

    PubMed Central

    2010-01-01

    Background Cancer cells undergo massive alterations to their DNA methylation patterns that result in aberrant gene expression and malignant phenotypes. However, the mechanisms that underlie methylome changes are not well understood nor is the genomic distribution of DNA methylation changes well characterized. Results Here, we performed methylated DNA immunoprecipitation combined with high-throughput sequencing (MeDIP-seq) to obtain whole-genome DNA methylation profiles for eight human breast cancer cell (BCC) lines and for normal human mammary epithelial cells (HMEC). The MeDIP-seq analysis generated non-biased DNA methylation maps by covering almost the entire genome with sufficient depth and resolution. The most prominent feature of the BCC lines compared to HMEC was a massively reduced methylation level particularly in CpG-poor regions. While hypomethylation did not appear to be associated with particular genomic features, hypermethylation preferentially occurred at CpG-rich gene-related regions independently of the distance from transcription start sites. We also investigated methylome alterations during epithelial-to-mesenchymal transition (EMT) in MCF7 cells. EMT induction was associated with specific alterations to the methylation patterns of gene-related CpG-rich regions, although overall methylation levels were not significantly altered. Moreover, approximately 40% of the epithelial cell-specific methylation patterns in gene-related regions were altered to those typical of mesenchymal cells, suggesting a cell-type specific regulation of DNA methylation. Conclusions This study provides the most comprehensive analysis to date of the methylome of human mammary cell lines and has produced novel insights into the mechanisms of methylome alteration during tumorigenesis and the interdependence between DNA methylome alterations and morphological changes. PMID:20181289

  15. Aberrant life cycle of human immunodeficiency virus type 1 CRF15_01B-like clinical isolates from Thailand in human CD4+ T-cell lines.

    PubMed

    Warachit, Jiranan; Iwabu, Yukie; Li, Yong-Gang; Li, Gui-Mei; Isarangkura, Panasda; Ibrahim, Madiha S; Balachandra, Kruavon; Tsuji, Shoutaro; Ikuta, Kazuyoshi

    2007-04-01

    Human immunodeficiency virus type 1 (HIV-1) is separated into several subtypes and circulating recombinant forms (CRFs). Here, infections of 4 clinical isolates (0-47-1, CU98-26, CU98-28, and CU98-31) from Thailand were examined in human CD4(+) T-cell lines, MT-4 and MOLT-4. The CU98-26 isolates in both cells and 0-47-1 in MT-4 established chronic infections, as in control 2 subtype B isolates from Japan, while 0-47-1 in MOLT-4 caused a latent infection. In contrast, CU98-28 and CU98-31 established aberrant infections in both cells. Integrated provirus was detected in all the chronic infections, including 0-47-1 in both cells. In contrast, extrachromosomal circular forms of HIV-1 DNA were detected in CU98-28- and CU98-31-infected cells, whereas the amount of the integrated form was below the limit of detection. Interestingly, phylogenetic trees and sequencing revealed that all the Thai isolates, except 0-47-1, displayed CRF15_01B-like mosaic structures of CRF01_AE with subtype B-like sequences in several regions that were apparently different from those of the inocula in peripheral blood mononuclear cells. Thus, in the infections of most of the above Thai isolates it was suggested that a minor population with mosaic patterns having multiple breakpoints between CRF01_AE and subtype B in the inocula could be selected by the T-cell lines.

  16. Exosome mediated growth effect on the non-growing pre-B acute lymphoblastic leukemia cells at low starting cell density

    PubMed Central

    Patel, Sapan J; Darie, Costel C; Clarkson, Bayard D

    2016-01-01

    Tumors contain heterogeneous cell populations and achieve dominance by functioning as collective systems. The mechanisms underlying the aberrant growth and interactions between cells are not very well understood. The pre-B acute lymphoblastic leukemia cells we studied were obtained directly from a patient with Ph+ ALL. A new Ph+ ALL cell line (ALL3) was established from the leukemic cells growing as ascitic cells in his pleural fluid. The patient died of his disease shortly after the cells were obtained. ALL3 cells grow well at high cell densities (HD), but not at low cell densities. ALL3 cells are very sensitive to potent tyrosine kinase inhibitors (TKIs) such as Dasatinib and PD166325, but less sensitive to AMN 107, Imatinib, and BMS 214662 (a farnesyl transferase inhibitor). Here, we show that the growth of the LD ALL3 cells can be stimulated to grow in the presence of diffusible, soluble factors secreted by ALL3 cells themselves growing at high density. We also show that exosomes, part of the secretome components, are also able to stimulate the growth of the non-growing LD ALL3 cells and modulate their proliferative behavior. Characterization of the exosome particles also showed that the HD ALL3 cells are able to secret them in large quantities and that they are capable of inducing the growth of the LD ALL3 cells without which they will not survive. Direct stimulation of non-growing LD ALL3 cells using purified exosomes shows that the ALL3 cells can also communicate with each other by means of exchange of exosomes independently of direct cell-cell contacts or diffusible soluble stimulatory factors secreted by HD ALL3 cells. PMID:27725845

  17. Aberrant high expression of immunoglobulin G in epithelial stem/progenitor-like cells contributes to tumor initiation and metastasis

    PubMed Central

    Wang, Fulin; Wang, Chong; Zhang, Jingxuan; Chu, Ming; Jiang, Dongyang; Xiao, Lin; Shao, Wenwei; Sheng, Zhengzuo; Tao, Xia; Huo, Lei; Yin, C. Cameron; Zhang, Youhui; Lee, Gregory; Huang, Jing; Li, Zihai; Qiu, Xiaoyan

    2015-01-01

    High expression of immunoglobulin G (IgG) in many non-B cell malignancies and its non-conventional roles in promoting proliferation and survival of cancer cells have been demonstrated. However, the precise function of non-B IgG remains incompletely understood. Here we define the antigen specificity of RP215, a monoclonal antibody that specifically recognizes the IgG in cancer cells. Using RP215, our study shows that IgG is overexpressed in cancer cells of epithelial lineage, especially cells with cancer stem/progenitor cell-like features. The RP215-recognized IgG is primarily localized on the cell surface, particularly lamellipodia-like structures. Cells with high IgG display higher migration, increased invasiveness and metastasis, and enhanced self-renewal and tumorgenecity ability in vitro and in vivo. Importantly, depletion of IgG in breast cancer leads to reduced adhesion, invasion and self-renewal and increased apoptosis of cancer cells. We conclude that high expression of IgG is a novel biomarker of tumor progression, metastasis and cancer stem cell maintenance and demonstrate the potential therapeutic benefits of RP215-recognized IgG targeted strategy. PMID:26472025

  18. Aberrant chimeric RNA GOLM1-MAK10 encoding a secreted fusion protein as a molecular signature for human esophageal squamous cell carcinoma

    PubMed Central

    Zhang, Hao; Lin, Wan; Kannan, Kalpana; Luo, Liming; Li, Jing; Chao, Pei-Wen; Wang, Yan; Chen, Yu-Ping; Gu, Jiang; Yen, Laising

    2013-01-01

    It is increasingly recognized that chimeric RNAs may exert a novel layer of cellular complexity that contributes to oncogenesis and cancer progression, and could be utilized as molecular biomarkers and therapeutic targets. To date yet no fusion chimeric RNAs have been identified in esophageal cancer, the 6th most frequent cause of cancer death in the world. While analyzing the expression of 32 recurrent cancer chimeric RNAs in esophageal squamous cell carcinoma (ESCC) from patients and cancer cell lines, we identified GOLM1-MAK10, as a highly cancer-enriched chimeric RNA in ESCC. In situ hybridization revealed that the expression of the chimera is largely restricted to cancer cells in patient tumors, and nearly undetectable in non-neoplastic esophageal tissue from normal subjects. The aberrant chimera closely correlated with histologic differentiation and lymph node metastasis. Furthermore, we demonstrate that chimera GOLM1-MAK10 encodes a secreted fusion protein. Mechanistic studies reveal that GOLM1-MAK10 is likely derived from transcription read-through/splicing rather than being generated from a fusion gene. Collectively, these findings provide novel insights into the molecular mechanism involved in ESCC and provide a novel potential target for future therapies. The secreted fusion protein translated from GOLM1-MAK10 could also serve as a unique protein signature detectable by standard non-invasive assays. These observations are critical as there is no clinically useful molecular signature available for detecting this deadly disease or monitoring the treatment response. PMID:24243830

  19. WNT4 mediates the autocrine effects of growth hormone in mammary carcinoma cells.

    PubMed

    Vouyovitch, Cécile M; Perry, Jo K; Liu, Dong Xu; Bezin, Laurent; Vilain, Eric; Diaz, Jean-Jacques; Lobie, Peter E; Mertani, Hichem C

    2016-07-01

    The expression of Wingless and Int-related protein (Wnt) ligands is aberrantly high in human breast cancer. We report here that WNT4 is significantly upregulated at the mRNA and protein level in mammary carcinoma cells expressing autocrine human growth hormone (hGH). Depletion of WNT4 using small interfering (si) RNA markedly decreased the rate of human breast cancer cell proliferation induced by autocrine hGH. Forced expression of WNT4 in the nonmalignant human mammary epithelial cell line MCF-12A stimulated cell proliferation in low and normal serum conditions, enhanced cell survival and promoted anchorage-independent growth and colony formation in soft agar. The effects of sustained production of WNT4 were concomitant with upregulation of proliferative markers (c-Myc, Cyclin D1), the survival marker BCL-XL, the putative WNT4 receptor FZD6 and activation of ERK1 and STAT3. Forced expression of WNT4 resulted in phenotypic conversion of MCF-12A cells, such that they exhibited the molecular and morphological characteristics of mesenchymal cells with increased cell motility. WNT4 production resulted in increased mesenchymal and cytoskeletal remodeling markers, promoted actin cytoskeleton reorganization and led to dissolution of cell-cell contacts. In xenograft studies, tumors with autocrine hGH expressed higher levels of WNT4 and FZD6 when compared with control tumors. In addition, Oncomine data indicated that WNT4 expression is increased in neoplastic compared with normal human breast tissue. Accordingly, immunohistochemical detection of WNT4 in human breast cancer biopsies revealed higher expression in tumor tissue vs normal breast epithelium. WNT4 is thus an autocrine hGH-regulated gene involved in the growth and development of the tumorigenic phenotype.

  20. WNT4 mediates the autocrine effects of growth hormone in mammary carcinoma cells.

    PubMed

    Vouyovitch, Cécile M; Perry, Jo K; Liu, Dong Xu; Bezin, Laurent; Vilain, Eric; Diaz, Jean-Jacques; Lobie, Peter E; Mertani, Hichem C

    2016-07-01

    The expression of Wingless and Int-related protein (Wnt) ligands is aberrantly high in human breast cancer. We report here that WNT4 is significantly upregulated at the mRNA and protein level in mammary carcinoma cells expressing autocrine human growth hormone (hGH). Depletion of WNT4 using small interfering (si) RNA markedly decreased the rate of human breast cancer cell proliferation induced by autocrine hGH. Forced expression of WNT4 in the nonmalignant human mammary epithelial cell line MCF-12A stimulated cell proliferation in low and normal serum conditions, enhanced cell survival and promoted anchorage-independent growth and colony formation in soft agar. The effects of sustained production of WNT4 were concomitant with upregulation of proliferative markers (c-Myc, Cyclin D1), the survival marker BCL-XL, the putative WNT4 receptor FZD6 and activation of ERK1 and STAT3. Forced expression of WNT4 resulted in phenotypic conversion of MCF-12A cells, such that they exhibited the molecular and morphological characteristics of mesenchymal cells with increased cell motility. WNT4 production resulted in increased mesenchymal and cytoskeletal remodeling markers, promoted actin cytoskeleton reorganization and led to dissolution of cell-cell contacts. In xenograft studies, tumors with autocrine hGH expressed higher levels of WNT4 and FZD6 when compared with control tumors. In addition, Oncomine data indicated that WNT4 expression is increased in neoplastic compared with normal human breast tissue. Accordingly, immunohistochemical detection of WNT4 in human breast cancer biopsies revealed higher expression in tumor tissue vs normal breast epithelium. WNT4 is thus an autocrine hGH-regulated gene involved in the growth and development of the tumorigenic phenotype. PMID:27323961

  1. [Stem cells and growth factors in wound healing].

    PubMed

    Pikuła, Michał; Langa, Paulina; Kosikowska, Paulina; Trzonkowski, Piotr

    2015-01-02

    Wound healing is a complex process which depends on the presence of various types of cells, growth factors, cytokines and the elements of extracellular matrix. A wound is a portal of entry for numerous pathogens, therefore during the evolution wound healing process has formed very early, being critical for the survival of every individual. Stem cells, which give rise to their early descendants progenitor cells and subsequently differentiated cells, play a specific role in the process of wound healing. Among the most important cells which take part in wound healing the following cells need to be distinguished: epidermal stem cells, dermal precursor of fibroblasts, adipose-derived stem cells as well as bone marrow cells. The activity of these cells is strictly regulated by various growth factors, inter alia epidermal growth factor (EGF), fibroblast growth factor (FGF), platelet-derived growth factor (PDGF), transforming growth factor (TGF), vascular endothelial growth factor (VEGF). Any disorders in functioning of stem cells and biological activity of growth factors may lead to the defects in wound healing, for instance delayed wound healing or creation of hypertrophic scars. Therefore, knowledge concerning the mechanisms of wound healing is extremely essential from clinical point of view. In this review the current state of the knowledge of the role of stem cells and growth factors in the process of wound healing has been presented. Moreover, some clinical aspects of wound healing as well as the possibility of the therapy based on stem cells and growth factors have included.

  2. Diesel exhaust particulate matter dispersed in a phospholipid surfactant induces chromosomal aberrations and micronuclei but not 6-thioguanine-resistant gene mutation in V79 cells.

    PubMed

    Gu, Zu-Wei; Keane, Michael J; Ong, Tong-man; Wallace, William E

    2005-03-26

    Diesel exhaust particulate material (DPM) was assayed for induction of chromosomal aberrations (CA), micronucleus (MN) formation, and 6-thioguanine-resistant (TG9 gene mutation in V79 cells as a dispersion in dipalmitoyl phosphatidylcholine (DPPC) in physiological saline, a simulated pulmonary surfactant. Filter-collected automobile DPM provided for the study was not organic solvent extracted, but was directly mixed into DPPC in saline dispersion as a model of pulmonary surfactant conditioning of a soot particle depositing in a lung alveolus. A statistically significant difference was found between treated and control groups at all concentrations tested in a CA assay. Assay for MN induction also gave a positive response: Above 50 microg/ml, the frequencies of micronucleated cells (MNC) were about 2 times higher than those in the control group. The forward gene mutation assay did not show a positive response when cells were treated with up to 136 microg DPM/ml for 24 h, as dispersion in DPPC in saline. Some comparison assays were run on direct dispersions of the DPM into dimethyl sulfoxide, with results equivalent to those seen with a DPPC-saline preparation: DPM in dimethyl sulfoxide (DMSO) was positive for MN induction but was negative for forward gene mutation in V79 cells. The positive clastogenicity results are consistent with other studies of DPM dispersed into DPPC-saline surfactant that have shown activity in mammalian cells for sister chromatid exchange, unscheduled DNA synthesis, and MN induction. The forward gene mutation negative results are consistent with studies of that assay applied to V79 cells challenged with DPM solvent extract.

  3. Functional inactivation of endogenous MDM2 and CHIP by HSP90 causes aberrant stabilization of mutant p53 in human cancer cells.

    PubMed

    Li, Dun; Marchenko, Natalia D; Schulz, Ramona; Fischer, Victoria; Velasco-Hernandez, Talia; Talos, Flaminia; Moll, Ute M

    2011-05-01

    The tight control of wild-type p53 by mainly MDM2 in normal cells is permanently lost in tumors harboring mutant p53, which exhibit dramatic constitutive p53 hyperstabilization that far exceeds that of wild-type p53 tumors. Importantly, mutant p53 hyperstabilization is critical for oncogenic gain of function of mutant p53 in vivo. Current insight into the mechanism of this dysregulation is fragmentary and largely derived from ectopically constructed cell systems. Importantly, mutant p53 knock-in mice established that normal mutant p53 tissues have sufficient enzymatic reserves in MDM2 and other E3 ligases to maintain full control of mutant p53. We find that in human cancer cells, endogenous mutant p53, despite its ability to interact with MDM2, suffers from a profound lack of ubiquitination as the root of its degradation defect. In contrast to wild-type p53, the many mutant p53 proteins which are conformationally aberrant are engaged in complexes with the HSP90 chaperone machinery to prevent its aggregation. In contrast to wild-type p53 cancer cells, we show that in mutant p53 cancer cells, this HSP90 interaction blocks the endogenous MDM2 and CHIP (carboxy-terminus of Hsp70-interacting protein) E3 ligase activity. Interference with HSP90 either by RNA interference against HSF1, the transcriptional regulator of the HSP90 pathway, or by direct knockdown of Hsp90 protein or by pharmacologic inhibition of Hsp90 activity with 17AAG (17-allylamino-17-demethoxygeldanamycin) destroys the complex, liberates mutant p53, and reactivates endogenous MDM2 and CHIP to degrade mutant p53. Of note, 17AAG induces a stronger viability loss in mutant p53 than in wild-type p53 cancer cells. Our data support the rationale that suppression of mutant p53 levels in vivo in established cancers might achieve clinically significant effects.

  4. Aberrant Proliferation of Differentiating Alveolar Cells Induces Hyperplasia in Resting Mammary Glands of SV40-TAg Transgenic Mice

    PubMed Central

    Quante, Timo; Wegwitz, Florian; Abe, Julia; Rossi, Alessandra; Deppert, Wolfgang; Bohn, Wolfgang

    2014-01-01

    WAP-T1 transgenic mice express SV40-TAg under control of the whey acidic protein (WAP) promoter, which directs activity of this strong viral oncogene to luminal cells of the mammary gland. Resting uniparous WAP-T1 glands develop hyperplasia composed of TAg positive cells prior to appearance of advanced tumor stages. We show that cells in hyperplasia display markers of alveolar differentiation, suggesting that TAg targets differentiating cells of the alveolar compartment. The glands show significant expression of Elf5 and milk genes (Lalba, Csn2, and Wap). TAg expressing cells largely co-stain with antibodies to Elf5, lack the epithelial marker Sca1, and are hormone receptor negative. High expression levels of Elf5 but not of milk genes are also seen in resting glands of normal BALB/c mice. This indicates that expression of Elf5 in resting WAP-T1 glands is not specifically induced by TAg. CK6a positive luminal cells lack TAg. These cells co-express the markers prominin-1, CK6a, and Sca1, and are positive for hormone receptors. These hormone sensitive cells localize to ducts and seem not to be targeted by TAg. Despite reaching an advanced stage in alveolar differentiation, the cells in hyperplasia do not exit the cell cycle. Thus, expression of TAg in conjunction with regular morphogenetic processes of alveologenesis seem to provide the basis for a hormone independent, unscheduled proliferation of differentiating cells in resting glands of WAP-T1 transgenic mice, leading to the formation of hyperplastic lesions. PMID:25019062

  5. The Hematopoietic System–specific Minor Histocompatibility Antigen HA-1 Shows Aberrant Expression in Epithelial Cancer Cells

    PubMed Central

    Klein, Christoph A.; Wilke, Martina; Pool, Jos; Vermeulen, Corine; Blokland, Els; Burghart, Elke; Krostina, Sabine; Wendler, Nicole; Passlick, Bernward; Riethmüeller, Gert; Goulmy, Els

    2002-01-01

    Allogeneic stem cell transplantation (SCT) can induce curative graft-versus-tumor reactions in patients with hematological malignancies and solid tumors. The graft-versus-tumor reaction after human histocompatibility leukocyte antigen (HLA)-identical SCT is mediated by alloimmune donor T cells specific for polymorphic minor histocompatibility antigens (mHags). Among these, the mHag HA-1 was found to be restricted to the hematopoietic system. Here, we report on the HA-1 ribonucleic acid expression by microdissected carcinoma tissues and by single disseminated tumor cells isolated from patients with various epithelial tumors. The HA-1 peptide is molecularly defined, as it forms an immunogenic peptide ligand with HLA-A2 on the cell membrane of carcinoma cell lines. HA-1–specific cytotoxic T cells lyse epithelial tumor cell lines in vitro, whereas normal epithelial cells are not recognized. Thus, HA-1–specific immunotherapy combined with HLA-identical allogeneic SCT may now be feasible for patients with HA-1+ carcinomas. PMID:12163564

  6. Inhibition of p300 histone acetyltransferase activity in palate mesenchyme cells attenuates Wnt signaling via aberrant E-cadherin expression.

    PubMed

    Warner, Dennis R; Smith, Scott C; Smolenkova, Irina A; Pisano, M Michele; Greene, Robert M

    2016-03-01

    p300 is a multifunctional transcriptional coactivator that interacts with numerous transcription factors and exhibits protein/histone acetyltransferase activity. Loss of p300 function in humans and in mice leads to craniofacial defects. In this study, we demonstrated that inhibition of p300 histone acetyltransferase activity with the compound, C646, altered the expression of several genes, including Cdh1 (E-cadherin) in mouse maxillary mesenchyme cells, which are the cells that give rise to the secondary palate. The increased expression of plasma membrane-bound E-cadherin was associated with reduced cytosolic β-catenin, that led to attenuated signaling through the canonical Wnt pathway. Furthermore, C646 reduced both cell proliferation and the migratory ability of these cells. These results suggest that p300 histone acetyltransferase activity is critical for Wnt-dependent palate mesenchymal cell proliferation and migration, both processes that play a significant role in morphogenesis of the palate.

  7. Genome-Wide Loss of Heterozygosity and DNA Copy Number Aberration in HPV-Negative Oral Squamous Cell Carcinoma and Their Associations with Disease-Specific Survival.

    PubMed

    Chen, Chu; Zhang, Yuzheng; Loomis, Melissa M; Upton, Melissa P; Lohavanichbutr, Pawadee; Houck, John R; Doody, David R; Mendez, Eduardo; Futran, Neal; Schwartz, Stephen M; Wang, Pei

    2015-01-01

    Oral squamous cell cancer of the oral cavity and oropharynx (OSCC) is associated with high case-fatality. For reasons that are largely unknown, patients with the same clinical and pathologic staging have heterogeneous response to treatment and different probability of recurrence and survival, with patients with Human Papillomavirus (HPV)-positive oropharyngeal tumors having the most favorable survival. To gain insight into the complexity of OSCC and to identify potential chromosomal changes that may be associated with OSCC mortality, we used Affymtrix 6.0 SNP arrays to examine paired DNA from peripheral blood and tumor cell populations isolated by laser capture microdissection to assess genome-wide loss of heterozygosity (LOH) and DNA copy number aberration (CNA) and their associations with risk factors, tumor characteristics, and oral cancer-specific mortality among 75 patients with HPV-negative OSCC. We found a highly heterogeneous and complex genomic landscape of HPV-negative tumors, and identified regions in 4q, 8p, 9p and 11q that seem to play an important role in oral cancer biology and survival from this disease. If confirmed, these findings could assist in designing personalized treatment or in the creation of models to predict survival in patients with HPV-negative OSCC.

  8. Antioxidants in aqueous extract of Myristica fragrans (Houtt.) suppress mitosis and cyclophosphamide-induced chromosomal aberrations in Allium cepa L. cells.

    PubMed

    Akinboro, Akeem; Mohamed, Kamaruzaman Bin; Asmawi, Mohd Zaini; Sulaiman, Shaida Fariza; Sofiman, Othman Ahmad

    2011-11-01

    In this study, freeze-dried water extract from the leaves of Myristica fragrans (Houtt.) was tested for mutagenic and antimutagenic potentials using the Allium cepa assay. Freeze-dried water extract alone and its combination with cyclophosphamide (CP) (50 mg/kg) were separately dissolved in tap water at 500, 1000, 2000, and 4000 mg/kg. Onions (A. cepa) were suspended in the solutions and controls for 48 h in the dark. Root tips were prepared for microscopic evaluation. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) free radicals' scavenging power of the extract was tested using butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) as standards. Water extract of Myristica fragrans scavenged free radicals better than BHA, but worse than BHT. The extract alone, as well as in combination with CP suppressed cell division, and induced chromosomal aberrations that were insignificantly different from the negative control (P ≤ 0.05). However, cytotoxic and mutagenic actions of CP were considerably suppressed. The observed effects on cell division and chromosomes of A. cepa may be principally connected to the antioxidant properties of the extract. The obtained results suggest mitodepressive and antimutagenic potentials of water extract of the leaves of M. fragrans as desirable properties of a promising anticancer agent.

  9. Genome-Wide Loss of Heterozygosity and DNA Copy Number Aberration in HPV-Negative Oral Squamous Cell Carcinoma and Their Associations with Disease-Specific Survival.

    PubMed

    Chen, Chu; Zhang, Yuzheng; Loomis, Melissa M; Upton, Melissa P; Lohavanichbutr, Pawadee; Houck, John R; Doody, David R; Mendez, Eduardo; Futran, Neal; Schwartz, Stephen M; Wang, Pei

    2015-01-01

    Oral squamous cell cancer of the oral cavity and oropharynx (OSCC) is associated with high case-fatality. For reasons that are largely unknown, patients with the same clinical and pathologic staging have heterogeneous response to treatment and different probability of recurrence and survival, with patients with Human Papillomavirus (HPV)-positive oropharyngeal tumors having the most favorable survival. To gain insight into the complexity of OSCC and to identify potential chromosomal changes that may be associated with OSCC mortality, we used Affymtrix 6.0 SNP arrays to examine paired DNA from peripheral blood and tumor cell populations isolated by laser capture microdissection to assess genome-wide loss of heterozygosity (LOH) and DNA copy number aberration (CNA) and their associations with risk factors, tumor characteristics, and oral cancer-specific mortality among 75 patients with HPV-negative OSCC. We found a highly heterogeneous and complex genomic landscape of HPV-negative tumors, and identified regions in 4q, 8p, 9p and 11q that seem to play an important role in oral cancer biology and survival from this disease. If confirmed, these findings could assist in designing personalized treatment or in the creation of models to predict survival in patients with HPV-negative OSCC. PMID:26247464

  10. Genome-Wide Loss of Heterozygosity and DNA Copy Number Aberration in HPV-Negative Oral Squamous Cell Carcinoma and Their Associations with Disease-Specific Survival

    PubMed Central

    Chen, Chu; Zhang, Yuzheng; Loomis, Melissa M.; Upton, Melissa P.; Lohavanichbutr, Pawadee; Houck, John R.; Doody, David R.; Mendez, Eduardo; Futran, Neal; Schwartz, Stephen M.; Wang, Pei

    2015-01-01

    Oral squamous cell cancer of the oral cavity and oropharynx (OSCC) is associated with high case-fatality. For reasons that are largely unknown, patients with the same clinical and pathologic staging have heterogeneous response to treatment and different probability of recurrence and survival, with patients with Human Papillomavirus (HPV)-positive oropharyngeal tumors having the most favorable survival. To gain insight into the complexity of OSCC and to identify potential chromosomal changes that may be associated with OSCC mortality, we used Affymtrix 6.0 SNP arrays to examine paired DNA from peripheral blood and tumor cell populations isolated by laser capture microdissection to assess genome-wide loss of heterozygosity (LOH) and DNA copy number aberration (CNA) and their associations with risk factors, tumor characteristics, and oral cancer-specific mortality among 75 patients with HPV-negative OSCC. We found a highly heterogeneous and complex genomic landscape of HPV-negative tumors, and identified regions in 4q, 8p, 9p and 11q that seem to play an important role in oral cancer biology and survival from this disease. If confirmed, these findings could assist in designing personalized treatment or in the creation of models to predict survival in patients with HPV-negative OSCC. PMID:26247464

  11. M-FISH Analysis of Chromosome Aberrations in Human Fibroblast Cells After In Vitro Exposure to Low- and High-LET Radiation

    NASA Technical Reports Server (NTRS)

    Wu, Honglu; Furusawa, Yoshiya; George, Kerry; Kawata, Tetsuya; Cucinotta, Francis

    2002-01-01

    The recently commercialized multiplex fluorescence in situ hybridization (m-FISH) technique, which allows human chromosomes to be painted in 24 different colors, was used to analyze chromosome aberrations in diploid human fibroblast cells after in vitro radiation exposure. Confluent flasks of a normal primary fibroblast cell line (AG 1522) were irradiated at high dose rates with either gamma rays or 200 MeV/nucleon Fe ions (LET = 440 keV/micron), incubated at 37 C for 24 hours after exposure, and subsequently subcultured. A chemically induced premature chromosome condensation technique was used to collect chromosome samples 32 hours after subculture. Results showed that the fraction of exchanges which were identified as complex, i.e. involving misrejoining of three or more DSB, were higher in the Fe-irradiated samples compared with the gamma-irradiated samples, as has been shown previously using FISH with one or two painted chromosomes . The ratios of complex/simple type exchanges were similar for samples irradiated with 0.7 Gy and 3 Gy of Fe ions, although exchanges involving five or more breaks were found only in 3 Gy irradiated samples. The fraction of incomplete exchanges was also higher in Fe- than gamma-irradiated samples. Data on the distribution of individual chromosome involvement in interchromosomal exchanges will be presented.

  12. Primary mediastinal (thymic) large B cell lymphoma with aberrant expression of CD3: a case report with review of the literature.

    PubMed

    Wang, Endi; Stoecker, Maggie

    2010-04-01

    We report the first case of primary mediastinal large B cell lymphoma (PMBL) with aberrant expression of CD3. PMBL is a subtype of diffuse large B cell lymphoma (DLBCL) and usually presents with bulky mediastinal lesions. Lineage ambiguity/infidelity is uncommon in DLBCL but has been described in sporadic case reports/series. A literature search identifies 13 additional cases of DLBCL expressing CD3, with the majority displaying cytoplasmic expression. Of the 14 total cases, 6 are pyothorax-associated lymphoma, 4 are conventional DLBCL, 2 are plasmablastic lymphoma, one is primary effusion lymphoma and one is PMBL. Two cases show genotypic ambiguity/infidelity with dual clonal IG and TCR gene rearrangements in addition to ambiguous immunophenotypes. Of the 13 cases tested for EBV status, 11 are positive, suggesting an important role of EBV in promoting lineage ambiguity/infidelity. A low threshold for testing EBV status is advocated in DLBCL with phenotypic ambiguity along with panels of immunohistochemical and molecular studies. PMID:20131102

  13. The peroxisome-proliferator activated receptor-γ agonist pioglitazone modulates aberrant T cell responses in systemic lupus erythematosus.

    PubMed

    Zhao, Wenpu; Berthier, Celine C; Lewis, Emily E; McCune, W Joseph; Kretzler, Matthias; Kaplan, Mariana J

    2013-10-01

    PPAR-γ agonists can suppress autoimmune responses and renal inflammation in murine lupus but the mechanisms implicated in this process remain unclear. We tested the effect of the PPAR-γ agonist pioglitazone in human lupus and control PBMCs with regard to gene regulation and various functional assays. By Affymetrix microarray analysis, several T cell-related pathways were significantly highlighted in pathway analysis in lupus PBMCs. Transcriptional network analysis showed IFN-γ as an important regulatory node, with pioglitazone treatment inducing transcriptional repression of various genes implicated in T cell responses. Confirmation of these suppressive effects was observed specifically in purified CD4+ T cells. Pioglitazone downregulated lupus CD4+ T cell effector proliferation and activation, while it significantly increased proliferation and function of lupus T regulatory cells. We conclude that PPAR-γ agonists selectively modulate CD4+ T cell function in SLE supporting the concept that pioglitazone and related,-agents should be explored as potential therapies in this disease.

  14. Cytogenetic and molecular characterization of a hepatosplenic T-cell lymphoma: report of a novel chromosomal aberration.

    PubMed

    Mandava, Swarna; Sonar, Reshma; Ahmad, Firoz; Yadav, Anil K; Chheda, Pratiksha; Ramani, Manisha; Gupta, Amar D; Das, Bibhu R

    2011-02-01

    Hepatosplenic T-cell lymphomas (HSTCL) are rare cancers and comprise 5% of peripheral T-cell lymphomas. These well-characterized extranodal lymphomas have a disguised onset, secondary to intrasinusoidal infiltration of the spleen, liver, and bone marrow, with a rapidly progressive course that is poorly responsive to chemotherapy and often ensues in the setting of immune system suppression. We describe the clinical, immunophenotypic, cytogenetic, fluorescence in situ hybridization, and molecular analyses for T cell receptor gene rearrangement in a 21-year-old man diagnosed with HSTCL. Immunophenotypic analysis revealed negativity for CD5 as well as double negativity for CD4/CD8 mature T-cell immunophenotype, which suggested the diagnosis of hepatosplenic T-cell lymphoma. Molecular analysis confirmed a TCR gene rearrangement, thereby verifying the common T-cell origin of the present HSTCL case. Furthermore, cytogenetic analysis revealed a novel chromosomal rearrangement, t(7;15)(p22;q21). Metaphase fluorescence in situ hybridization analysis confirmed the translocation of a chromosomal segment from 15q21 to 7p22.

  15. Aberrant expression of T cell and B cell markers in myelocyte/monocyte/histiocyte-derived lymphoma and leukemia cells. Is the infrequent expression of T/B cell markers sufficient to establish a lymphoid origin for Hodgkin's Reed-Sternberg cells?

    PubMed Central

    Hsu, S. M.; Hsu, P. L.

    1989-01-01

    Most Hodgkin's mononuclear cells and Reed-Sternberg (H-RS) cells are characterized by the expression of the antigen CD30, but not of T or B cell markers. A few H-RS cells, however, may express a limited number of T or B cell markers. Whether this expression is sufficient to allow the conclusion that H-RS cells are derived from T and/or B cells has been debated vigorously. The present study examined whether CD30 and aberrant T and B cell markers are expressed in cell lines that are well documented as being derived from the granulocyte/monocyte/histiocyte lineage. These cells included HL-60, KG-1, ML-1, THP-1, and U-937. Four other cell lines derived from patients with leukemias/lymphomas of monocytic or granulocytic origins also were studied. These cells included BV173, CML-Brown, CTV-2, and SU-DHL-1. If aberrant expression is detected, by analogy one may expect that rare T or B cell marker expression may occur in H-RS cells, because abundant evidence has indicated that H-RS cells may be related to cells in histiocyte lineage. In all nine of the cell lines studied, it was confirmed that numerous monocyte/granulocyte markers were expressed. The marker expression was enhanced after cells were induced to differentiate with phorbol ester (TPA) and tumor necrosis factor (TNF). It was noted that several T and B cell markers also were expressed by these cells. Unlike the expression of monocyte/granulocyte markers, the expression of T or B cell markers was not affected, or only minimally affected, by treatment of the cells with TPA or TNF. Five of the cell lines (BV173, CML-Brown, CTV-2, SU-DHL-1, and THP-1) were shown to be CD30-positive. In CTV-2 and BV173, the expression of CD30 was greatly increased after induction with phorbol ester or TNF. Based on these studies, the following conclusions were reached: 1) The expression of aberrant B or T cell markers is not an uncommon finding in granulocyte/monocyte/histiocyte-related neoplastic cells. 2) The expression of

  16. Ligand-independent canonical Wnt activity in canine mammary tumor cell lines associated with aberrant LEF1 expression.

    PubMed

    Gracanin, Ana; Timmermans-Sprang, Elpetra P M; van Wolferen, Monique E; Rao, Nagesha A S; Grizelj, Juraj; Vince, Silvijo; Hellmen, Eva; Mol, Jan A

    2014-01-01

    Pet dogs very frequently develop spontaneous mammary tumors and have been suggested as a good model organism for breast cancer research. In order to obtain an insight into underlying signaling mechanisms during canine mammary tumorigenesis, in this study we assessed the incidence and the mechanism of canonical Wnt activation in a panel of 12 canine mammary tumor cell lines. We show that a subset of canine mammary cell lines exhibit a moderate canonical Wnt activity that is dependent on Wnt ligands, similar to what has been described in human breast cancer cell lines. In addition, three of the tested canine mammary cell lines have a high canonical Wnt activity that is not responsive to inhibitors of Wnt ligand secretion. Tumor cell lines with highly active canonical Wnt signaling often carry mutations in key members of the Wnt signaling cascade. These cell lines, however, carry no mutations in the coding regions of intracellular Wnt pathway components (APC, β-catenin, GSK3β, CK1α and Axin1) and have a functional β-catenin destruction complex. Interestingly, however, the cell lines with high canonical Wnt activity specifically overexpress LEF1 mRNA and the knock-down of LEF1 significantly inhibits TCF-reporter activity. In addition, LEF1 is overexpressed in a subset of canine mammary carcinomas, implicating LEF1 in ligand-independent activation of canonical Wnt signaling in canine mammary tumors. We conclude that canonical Wnt activation may be a frequent event in canine mammary tumors both through Wnt ligand-dependent and novel ligand-independent mechanisms.

  17. Ligand-Independent Canonical Wnt Activity in Canine Mammary Tumor Cell Lines Associated with Aberrant LEF1 Expression

    PubMed Central

    van Wolferen, Monique E.; Rao, Nagesha A. S.; Grizelj, Juraj; Vince, Silvijo; Hellmen, Eva; Mol, Jan A.

    2014-01-01

    Pet dogs very frequently develop spontaneous mammary tumors and have been suggested as a good model organism for breast cancer research. In order to obtain an insight into underlying signaling mechanisms during canine mammary tumorigenesis, in this study we assessed the incidence and the mechanism of canonical Wnt activation in a panel of 12 canine mammary tumor cell lines. We show that a subset of canine mammary cell lines exhibit a moderate canonical Wnt activity that is dependent on Wnt ligands, similar to what has been described in human breast cancer cell lines. In addition, three of the tested canine mammary cell lines have a high canonical Wnt activity that is not responsive to inhibitors of Wnt ligand secretion. Tumor cell lines with highly active canonical Wnt signaling often carry mutations in key members of the Wnt signaling cascade. These cell lines, however, carry no mutations in the coding regions of intracellular Wnt pathway components (APC, β-catenin, GSK3β, CK1α and Axin1) and have a functional β-catenin destruction complex. Interestingly, however, the cell lines with high canonical Wnt activity specifically overexpress LEF1 mRNA and the knock-down of LEF1 significantly inhibits TCF-reporter activity. In addition, LEF1 is overexpressed in a subset of canine mammary carcinomas, implicating LEF1 in ligand-independent activation of canonical Wnt signaling in canine mammary tumors. We conclude that canonical Wnt activation may be a frequent event in canine mammary tumors both through Wnt ligand-dependent and novel ligand–independent mechanisms. PMID:24887235

  18. Ligand-independent canonical Wnt activity in canine mammary tumor cell lines associated with aberrant LEF1 expression.

    PubMed

    Gracanin, Ana; Timmermans-Sprang, Elpetra P M; van Wolferen, Monique E; Rao, Nagesha A S; Grizelj, Juraj; Vince, Silvijo; Hellmen, Eva; Mol, Jan A

    2014-01-01

    Pet dogs very frequently develop spontaneous mammary tumors and have been suggested as a good model organism for breast cancer research. In order to obtain an insight into underlying signaling mechanisms during canine mammary tumorigenesis, in this study we assessed the incidence and the mechanism of canonical Wnt activation in a panel of 12 canine mammary tumor cell lines. We show that a subset of canine mammary cell lines exhibit a moderate canonical Wnt activity that is dependent on Wnt ligands, similar to what has been described in human breast cancer cell lines. In addition, three of the tested canine mammary cell lines have a high canonical Wnt activity that is not responsive to inhibitors of Wnt ligand secretion. Tumor cell lines with highly active canonical Wnt signaling often carry mutations in key members of the Wnt signaling cascade. These cell lines, however, carry no mutations in the coding regions of intracellular Wnt pathway components (APC, β-catenin, GSK3β, CK1α and Axin1) and have a functional β-catenin destruction complex. Interestingly, however, the cell lines with high canonical Wnt activity specifically overexpress LEF1 mRNA and the knock-down of LEF1 significantly inhibits TCF-reporter activity. In addition, LEF1 is overexpressed in a subset of canine mammary carcinomas, implicating LEF1 in ligand-independent activation of canonical Wnt signaling in canine mammary tumors. We conclude that canonical Wnt activation may be a frequent event in canine mammary tumors both through Wnt ligand-dependent and novel ligand-independent mechanisms. PMID:24887235

  19. New advances of microRNAs in glioma stem cells, with special emphasis on aberrant methylation of microRNAs.

    PubMed

    Zhao, Bing; Bian, Er-Bao; Li, Jia; Li, Jun

    2014-09-01

    Malignant brain tumors are thought to be originate from a small population of cells that display stem cell properties, including the capacity of self-renewal, multipotent differentiation, initiation of tumor tissues. Cancer stem cells (CSCs) have been identified in gliomas in which they are named as glioma stem cells (GSCs). GSCs, sharing some characteristics with normal neural stem cells (NSCs), contribute to the cellular origin for primary gliomas and the recurrence of malignant gliomas after current conventional therapy. Recently, increasing evidences have showed that miRNAs play a central role in GSCs. In this review we focus on the role of GSCs in gliomas and in the abnomal expression of miRNAs in GSCs. Furthermore, we also discuss epigenetic dysregulation of tumor-suppressor miRNAs by promoter DNA methylation is involved in the regulation of GSCs biology. Recent advances in understanding dysregulated expression of miRNAs and methylation of tumor-suppressor miRNAs in GSCs and their possible use as new therapeutic targets of gliomas.

  20. WE-D-BRE-05: Prediction of Late Radiation-Induced Proctitis in Prostate Cancer Patients Using Chromosome Aberration and Cell Proliferation Rate

    SciTech Connect

    Oh, J; Deasy, J

    2014-06-15

    Purpose: Chromosome damage and cell proliferation rate have been investigated as potential biomarkers for the early prediction of late radiationinduced toxicity. Incorporating these endpoints, we explored the predictive power for late radiation proctitis using a machine learning method. Methods: Recently, Beaton et al. showed that chromosome aberration and cell proliferation rate could be used as biomarkers to predict late radiation proctitis (Beaton et al. (2013) Int J Rad Onc Biol Phys, 85:1346–1352). For the identification of radiosensitive biomarkers, blood samples were collected from 10 patients with grade 3 late proctitis along with 20 control patients with grade 0 proctitis. After irradiation at 6 Gy, statistically significant difference was observed between the two groups, using the number of dicentrics and excess fragments, and the number of cells in metaphase 2 (M2). However, Beaton et al. did not show the usefulness of combining these endpoints. We reanalyzed the dataset to investigate whether incorporating these endpoints can increase the predictive power of radiation proctitis, using a support vector machine (SVM). Results: Using the SVM method with the number of fragments and M2 endpoints, perfect classification was achieved. In addition, to avoid biased estimate of the classification method, leave-one-out cross-validation (LOO-CV) was performed. The best performance was achieved when all three endpoints were used with 87% accuracy, 90% sensitivity, 85% specificity, and 0.85 AUC (the area under the receiver operating characteristic (ROC) curve). The most significant endpoint was the number of fragments that obtained 83% accuracy, 70% sensitivity, 90% specificity, and 0.82 AUC. Conclusion: We demonstrated that chromosome damage and cell proliferation rate could be significant biomarkers to predict late radiation proctitis. When these endpoints were used together in conjunction with a machine learning method, the better performance was obtained

  1. Bioactive proanthocyanidins inhibit growth and induce apoptosis in human melanoma cells by decreasing the accumulation of β-catenin

    PubMed Central

    VAID, MUDIT; SINGH, TRIPTI; PRASAD, RAM; KATIYAR, SANTOSH K.

    2016-01-01

    Melanoma is a highly aggressive form of skin cancer with poor survival rate. Aberrant activation of Wnt/β-catenin has been observed in nearly one-third of human melanoma cases thereby indicating that targeting Wnt/β-catenin signaling could be a promising strategy against melanoma development. In the present study, we determined chemotherapeutic effect of grape seed proanthocyanidins (GSPs) on the growth of melanoma cells and validated their protective effects in vivo using a xenograft mouse model, and assessed if β-catenin is the target of GSP chemotherapeutic effect. Our in vitro data show that treatment of A375 and Hs294t human melanoma cells with GSPs inhibit the growth of melanoma cells, which was associated with the reduction in the levels of β-catenin. Administration of dietary GSPs (0.2 and 0.5%, w/w) in supplementation with AIN76A control diet significantly inhibited the growth of melanoma tumor xenografts in nude mice. Furthermore, dietary GSPs inhibited the xenograft growth of Mel928 (β-catenin-activated), while did not inhibit the xenograft growth of Mel1011 (β-catenin-inactivated) cells. These observations were further verified by siRNA knockdown of β-catenin and forced overexpression of β-catenin in melanoma cells using a cell culture model. PMID:26676402

  2. Delivery of iron to human cells by bovine transferrin. Implications for the growth of human cells in vitro.

    PubMed Central

    Young, S P; Garner, C

    1990-01-01

    Following suggestions that transferrin present in fetal-bovine serum, a common supplement used in tissue-culture media, may not bind well to human cells, we have isolated the protein and investigated its interaction with both human and bovine cells. Bovine transferrin bound to a human cell line, K562, at 4 degrees C with a kd of 590 nM, whereas human transferrin bound with a kd of 3.57 nM, a 165-fold difference. With a bovine cell line, NBL4, bovine transferrin bound with the higher affinity, kd 9.09 nM, whereas human transferrin bound with a kd of 41.7 nM, only a 5-fold difference. These values were reflected in an 8.6-fold difference in the rate of iron delivery by the two proteins to human cells, whereas delivery to bovine cells was the same. Nevertheless, the bovine transferrin was taken up by the human cells by a specific receptor-mediated process. Human cells cultured in bovine diferric transferrin at 40 micrograms/ml, the concentration expected in the presence of 10% fetal-bovine serum, failed to thrive, whereas cells cultured in the presence of human transferrin proliferated normally. These results suggest that growth of human cells in bovine serum could give rise to a cellular iron deficiency, which may in turn lead to the selection of clones of cells adapted for survival with less iron. This has important consequences for the use of such cells as models, since they may have aberrant iron-dependent pathways and perhaps other unknown alterations in cell function. PMID:2302189

  3. Aberrant patterns of X chromosome inactivation in a new line of human embryonic stem cells established in physiological oxygen concentrations.

    PubMed

    de Oliveira Georges, Juliana Andrea; Vergani, Naja; Fonseca, Simone Aparecida Siqueira; Fraga, Ana Maria; de Mello, Joana Carvalho Moreira; Albuquerque, Maria Cecília R Maciel; Fujihara, Litsuko Shimabukuro; Pereira, Lygia Veiga

    2014-08-01

    One of the differences between murine and human embryonic stem cells (ESCs) is the epigenetic state of the X chromosomes in female lines. Murine ESCs (mESCs) present two transcriptionally active Xs that will undergo the dosage compensation process of XCI upon differentiation, whereas most human ESCs (hESCs) spontaneously inactivate one X while keeping their pluripotency. Whether this reflects differences in embryonic development of mice and humans, or distinct culture requirements for the two kinds of pluripotent cells is not known. Recently it has been shown that hESCs established in physiological oxygen levels are in a stable pre-XCI state equivalent to that of mESCs, suggesting that culture in low oxygen concentration is enough to preserve that epigenetic state of the X chromosomes. Here we describe the establishment of two new lines of hESCs under physiological oxygen level and the characterization of the XCI state in the 46,XX line BR-5. We show that a fraction of undifferentiated cells present XIST RNA accumulation and single H3K27me foci, characteristic of the inactive X. Moreover, analysis of allele specific gene expression suggests that pluripotent BR-5 cells present completely skewed XCI. Our data indicate that physiological levels of oxygen are not sufficient for the stabilization of the pre-XCI state in hESCs.

  4. Aberrant patterns of X chromosome inactivation in a new line of human embryonic stem cells established in physiological oxygen concentrations.

    PubMed

    de Oliveira Georges, Juliana Andrea; Vergani, Naja; Fonseca, Simone Aparecida Siqueira; Fraga, Ana Maria; de Mello, Joana Carvalho Moreira; Albuquerque, Maria Cecília R Maciel; Fujihara, Litsuko Shimabukuro; Pereira, Lygia Veiga

    2014-08-01

    One of the differences between murine and human embryonic stem cells (ESCs) is the epigenetic state of the X chromosomes in female lines. Murine ESCs (mESCs) present two transcriptionally active Xs that will undergo the dosage compensation process of XCI upon differentiation, whereas most human ESCs (hESCs) spontaneously inactivate one X while keeping their pluripotency. Whether this reflects differences in embryonic development of mice and humans, or distinct culture requirements for the two kinds of pluripotent cells is not known. Recently it has been shown that hESCs established in physiological oxygen levels are in a stable pre-XCI state equivalent to that of mESCs, suggesting that culture in low oxygen concentration is enough to preserve that epigenetic state of the X chromosomes. Here we describe the establishment of two new lines of hESCs under physiological oxygen level and the characterization of the XCI state in the 46,XX line BR-5. We show that a fraction of undifferentiated cells present XIST RNA accumulation and single H3K27me foci, characteristic of the inactive X. Moreover, analysis of allele specific gene expression suggests that pluripotent BR-5 cells present completely skewed XCI. Our data indicate that physiological levels of oxygen are not sufficient for the stabilization of the pre-XCI state in hESCs. PMID:24633531

  5. Matrilin-3 Chondrodysplasia Mutations Cause Attenuated Chondrogenesis, Premature Hypertrophy and Aberrant Response to TGF-β in Chondroprogenitor Cells

    PubMed Central

    Jayasuriya, Chathuraka T.; Zhou, Fiona H.; Pei, Ming; Wang, Zhengke; Lemme, Nicholas J.; Haines, Paul; Chen, Qian

    2014-01-01

    Studies have shown that mutations in the matrilin-3 gene (MATN3) are associated with multiple epiphyseal dysplasia (MED) and spondyloepimetaphyseal dysplasia (SEMD). We tested whether MATN3 mutations affect the differentiation of chondroprogenitor and/or mesenchymal stem cells, which are precursors to chondrocytes. ATDC5 chondroprogenitors stably expressing wild-type (WT) MATN3 underwent spontaneous chondrogenesis. Expression of chondrogenic markers collagen II and aggrecan was inhibited in chondroprogenitors carrying the MED or SEMD MATN3 mutations. Hypertrophic marker collagen X remained attenuated in WT MATN3 chondroprogenitors, whereas its expression was elevated in chondroprogenitors expressing the MED or SEMD mutant MATN3 gene suggesting that these mutations inhibit chondrogenesis but promote hypertrophy. TGF-β treatment failed to rescue chondrogenesis markers but dramatically increased collagen X mRNA expression in mutant MATN3 expressing chondroprogenitors. Synovium derived mesenchymal stem cells harboring the SEMD mutation exhibited lower glycosaminoglycan content than those of WT MATN3 in response to TGF-β. Our results suggest that the properties of progenitor cells harboring MATN3 chondrodysplasia mutations were altered, as evidenced by attenuated chondrogenesis and premature hypertrophy. TGF-β treatment failed to completely rescue chondrogenesis but instead induced hypertrophy in mutant MATN3 chondroprogenitors. Our data suggest that chondroprogenitor cells should be considered as a potential target of chondrodysplasia therapy. PMID:25196597

  6. Beyond growth: novel functions for bacterial cell wall hydrolases.

    PubMed

    Wyckoff, Timna J; Taylor, Jennifer A; Salama, Nina R

    2012-11-01

    The peptidoglycan cell wall maintains turgor pressure and cell shape of most bacteria. Cell wall hydrolases are essential, together with synthases, for growth and daughter cell separation. Recent work in diverse organisms has uncovered new cell wall hydrolases that act autonomously or on neighboring cells to modulate invasion of prey cells, cell shape, innate immune detection, intercellular communication, and competitor lysis. The hydrolases involved in these processes catalyze the cleavage of bonds throughout the sugar and peptide moities of peptidoglycan. Phenotypes associated with these diverse hydrolases reveal new functions of the bacterial cell wall beyond growth and division.

  7. Optical aberrations of intraocular lenses measured in vivo and in vitro

    NASA Astrophysics Data System (ADS)

    Barbero, Sergio; Marcos, Susana; Jiménez-Alfaro, Ignacio

    2003-10-01

    Corneal and ocular aberrations were measured in a group of eyes before and after cataract surgery with spherical intraocular lens (IOL) implantation by use of well-tested techniques developed in our laboratory. By subtraction of corneal from total aberration maps, we also estimated the optical quality of the intraocular lens in vivo. We found that aberrations in pseudophakic eyes are not significantly different from aberrations in eyes before cataract surgery or from previously reported aberrations in healthy eyes of the same age. However, aberrations in pseudophakic eyes are significantly higher than in young eyes. We found a slight increase of corneal aberrations after surgery. The aberrations of the IOL and the lack of balance of the corneal spherical aberrations by the spherical aberrations of the intraocular lens also degraded the optical quality in pseudophakic eyes. We also measured the aberrations of the IOL in vitro, using an eye cell model, and simulated the aberrations of the IOL on the basis of the IOL's physical parameters. We found a good agreement among in vivo, in vitro, and simulated measures of spherical aberration: Unlike the spherical aberration of the young crystalline lens, which tends to be negative, the spherical aberration of the IOL is positive and increases with lens power. Computer simulations and in vitro measurements show that tilts and decentrations might be contributors to the increased third-order aberrations in vivo in comparison with in vitro measurements.

  8. Aberrant Lipid Metabolism in the Forebrain Niche Suppresses Adult Neural Stem Cell Proliferation in an Animal Model of Alzheimer's Disease.

    PubMed

    Hamilton, Laura K; Dufresne, Martin; Joppé, Sandra E; Petryszyn, Sarah; Aumont, Anne; Calon, Frédéric; Barnabé-Heider, Fanie; Furtos, Alexandra; Parent, Martin; Chaurand, Pierre; Fernandes, Karl J L

    2015-10-01

    Lipid metabolism is fundamental for brain development and function, but its roles in normal and pathological neural stem cell (NSC) regulation remain largely unexplored. Here, we uncover a fatty acid-mediated mechanism suppressing endogenous NSC activity in Alzheimer's disease (AD). We found that postmortem AD brains and triple-transgenic Alzheimer's disease (3xTg-AD) mice accumulate neutral lipids within ependymal cells, the main support cell of the forebrain NSC niche. Mass spectrometry and microarray analyses identified these lipids as oleic acid-enriched triglycerides that originate from niche-derived rather than peripheral lipid metabolism defects. In wild-type mice, locally increasing oleic acid was sufficient to recapitulate the AD-associated ependymal triglyceride phenotype and inhibit NSC proliferation. Moreover, inhibiting the rate-limiting enzyme of oleic acid synthesis rescued proliferative defects in both adult neurogenic niches of 3xTg-AD mice. These studies support a pathogenic mechanism whereby AD-induced perturbation of niche fatty acid metabolism suppresses the homeostatic and regenerative functions of NSCs.

  9. Phase and birefringence aberration correction

    DOEpatents

    Bowers, Mark; Hankla, Allen

    1996-01-01

    A Brillouin enhanced four wave mixing phase conjugate mirror corrects phase aberrations of a coherent electromagnetic beam and birefringence induced upon that beam. The stimulated Brillouin scattering (SBS) phase conjugation technique is augmented to include Brillouin enhanced four wave mixing (BEFWM). A seed beam is generated by a main oscillator which arrives at the phase conjugate cell before the signal beams in order to initiate the Brillouin effect. The signal beam which is being amplified through the amplifier chain is split into two perpendicularly polarized beams. One of the two beams is chosen to be the same polarization as some component of the seed beam, the other orthogonal to the first. The polarization of the orthogonal beam is then rotated 90.degree. such that it is parallel to the other signal beam. The three beams are then focused into cell containing a medium capable of Brillouin excitation. The two signal beams are focused such that they cross the seed beam path before their respective beam waists in order to achieve BEFWM or the two signal beams are focused to a point or points contained within the focused cone angle of the seed beam to achieve seeded SBS, and thus negate the effects of all birefringent and material aberrations in the system.

  10. Phase and birefringence aberration correction

    DOEpatents

    Bowers, M.; Hankla, A.

    1996-07-09

    A Brillouin enhanced four wave mixing phase conjugate mirror corrects phase aberrations of a coherent electromagnetic beam and birefringence induced upon that beam. The stimulated Brillouin scattering (SBS) phase conjugation technique is augmented to include Brillouin enhanced four wave mixing (BEFWM). A seed beam is generated by a main oscillator which arrives at the phase conjugate cell before the signal beams in order to initiate the Brillouin effect. The signal beam which is being amplified through the amplifier chain is split into two perpendicularly polarized beams. One of the two beams is chosen to be the same polarization as some component of the seed beam, the other orthogonal to the first. The polarization of the orthogonal beam is then rotated 90{degree} such that it is parallel to the other signal beam. The three beams are then focused into cell containing a medium capable of Brillouin excitation. The two signal beams are focused such that they cross the seed beam path before their respective beam waists in order to achieve BEFWM or the two signal beams are focused to a point or points contained within the focused cone angle of the seed beam to achieve seeded SBS, and thus negate the effects of all birefringent and material aberrations in the system. 5 figs.

  11. Aberrant regulation of synthesis and degradation of viral proteins in coliphage lambda-infected UV-irradiated cells and in minicells.

    PubMed Central

    Shaw, J E; Epp, C; Pearson, M L; Reeve, J N

    1987-01-01

    The patterns of bacteriophage lambda proteins synthesized in UV-irradiated Escherichia coli cells and in anucleate minicells are significantly different; both systems exhibit aberrations of regulation in lambda gene expression. In unirradiated cells or cells irradiated with low UV doses (less than 600 J/m2), regulation of lambda protein synthesis is controlled by the regulatory proteins CI, N, CII, CIII, Cro, and Q. As the UV dose increases, activation of transcription of the cI, rexA, and int genes by CII and CIII proteins fails to occur and early protein synthesis, normally inhibited by the action of Cro, continues. After high UV doses (greater than 2,000 J/m2), late lambda protein synthesis does not occur. Progression through the sequence of regulatory steps in lambda gene expression is slower in infected minicells. In minicells, there is no detectable cII- and cIII-dependent synthesis of CI, RexA, or Int proteins and inhibition of early protein synthesis by Cro activity is always incomplete. The synthesis of early b region proteins is not subject to control by CI, N, or Cro proteins, and evidence is presented suggesting that, in minicells, transcription of the early b region is initiated at a promoter(s) within the b region. Proteolytic cleavage of the regulatory proteins O and N and of the capsid proteins C, B, and Nu3 is much reduced in infected minicells. Exposure of minicells to very high UV doses before infection does not completely inhibit late lambda protein synthesis. Images PMID:2957511

  12. Aberrant microRNA expression likely controls RAS oncogene activation during malignant transformation of human prostate epithelial and stem cells by arsenic.

    PubMed

    Ngalame, Ntube N O; Tokar, Erik J; Person, Rachel J; Xu, Yuanyuan; Waalkes, Michael P

    2014-04-01

    Inorganic arsenic (iAs), a human carcinogen, potentially targets the prostate. iAs malignantly transforms the RWPE-1 human prostate epithelial line to CAsE-PE cells, and a derivative normal stem cell (SC) line, WPE-stem, to As-Cancer SC (As-CSC) line. MicroRNAs (miRNA) are noncoding but exert negative control on expression by degradation or translational repression of target mRNAs. Aberrant miRNA expression is important in carcinogenesis. A miRNA array of CAsE-PE and As-CSC revealed common altered expression in both for pathways concerning oncogenesis, miRNA biogenesis, cell signaling, proliferation, and tumor metastasis and invasion. The KRAS oncogene is overexpressed in CAsE-PE cells but not by mutation or promoter hypomethylation, and is intensely overexpressed in As-CSC cells. In both transformants, decreased miRNAs targeting KRAS and RAS superfamily members occurred. Reduced miR-134, miR-373, miR-155, miR-138, miR-205, miR-181d, miR-181c, and let-7 in CAsE-PE cells correlated with increased target RAS oncogenes, RAN, RAB27A, RAB22A mRNAs, and KRAS protein. Reduced miR-143, miR-34c-5p, and miR-205 in As-CSC correlated with increased target RAN mRNA, and KRAS, NRAS, and RRAS proteins. The RAS/ERK and PI3K/PTEN/AKT pathways control cell survival, differentiation, and proliferation, and when dysregulated promote a cancer phenotype. iAs transformation increased expression of activated ERK kinase in both transformants and altered components of the PI3K/PTEN/AKT pathway including decreased PTEN and increases in BCL2, BCL-XL, and VEGF in the absence of AKT activation. Thus, dysregulated miRNA expression may be linked to RAS activation in both transformants.

  13. Single-cell dynamics reveals sustained growth during diauxic shifts.

    PubMed

    Boulineau, Sarah; Tostevin, Filipe; Kiviet, Daniel J; ten Wolde, Pieter Rein; Nghe, Philippe; Tans, Sander J

    2013-01-01

    Stochasticity in gene regulation has been characterized extensively, but how it affects cellular growth and fitness is less clear. We study the growth of E. coli cells as they shift from glucose to lactose metabolism, which is characterized by an obligatory growth arrest in bulk experiments that is termed the lag phase. Here, we follow the growth dynamics of individual cells at minute-resolution using a single-cell assay in a microfluidic device during this shift, while also monitoring lac expression. Mirroring the bulk results, the majority of cells displays a growth arrest upon glucose exhaustion, and resume when triggered by stochastic lac expression events. However, a significant fraction of cells maintains a high rate of elongation and displays no detectable growth lag during the shift. This ability to suppress the growth lag should provide important selective advantages when nutrients are scarce. Trajectories of individual cells display a highly non-linear relation between lac expression and growth, with only a fraction of fully induced levels being sufficient for achieving near maximal growth. A stochastic molecular model together with measured dependencies between nutrient concentration, lac expression level, and growth accurately reproduces the observed switching distributions. The results show that a growth arrest is not obligatory in the classic diauxic shift, and underscore that regulatory stochasticity ought to be considered in terms of its impact on growth and survival. PMID:23637881

  14. Absence of fks1p in lager brewing yeast results in aberrant cell wall composition and improved beer flavor stability.

    PubMed

    Wang, Jin-jing; Xu, Wei-na; Li, Xin'er; Li, Jia; Li, Qi

    2014-06-01

    The flavor stability during storage is very important to the freshness and shelf life of beer. However, beer fermented with a yeast strain which is prone to autolyze will significantly affect the flavor of product. In this study, the gene encoding β-1,3-glucan synthetase catalytic subunit (fks1) of the lager yeast was destroyed via self-clone strategy. β-1,3-glucan is the principle cell wall component, so fks1 disruption caused a decrease in β-1,3-glucan level and increase in chitin level in cell wall, resulting in the increased cell wall thickness. Comparing with wild-type strain, the mutant strain had 39.9 and 63.41 % less leakage of octanoic acid and decanoic acid which would significantly affect the flavor of beer during storage. Moreover, the results of European Brewery Convention tube fermentation test showed that the genetic manipulation to the industrial brewing yeast helped with the anti-staling ability, rather than affecting the fermentation ability. The thiobarbituric acid value reduced by 65.59 %, and the resistant staling value increased by 26.56 %. Moreover, the anti-staling index of the beer fermented with mutant strain increased by 2.64-fold than that from wild-type strain respectively. China has the most production and consumption of beer around the world, so the quality of beer has a significant impact on Chinese beer industry. The result of this study could help with the improvement of the quality of beer in China as well as around the world.

  15. Aberrant reduction of telomere repetitive sequences in plasma cell-free DNA for early breast cancer detection

    PubMed Central

    Wu, Xi; Tanaka, Hiromi

    2015-01-01

    Excessive telomere shortening is observed in breast cancer lesions when compared to adjacent non-cancerous tissues, suggesting that telomere length may represent a key biomarker for early cancer detection. Because tumor-derived, cell-free DNA (cfDNA) is often released from cancer cells and circulates in the bloodstream, we hypothesized that breast cancer development is associated with changes in the amount of telomeric cfDNA that can be detected in the plasma. To test this hypothesis, we devised a novel, highly sensitive and specific quantitative PCR (qPCR) assay, termed telomeric cfDNA qPCR, to quantify plasma telomeric cfDNA levels. Indeed, the internal reference primers of our design correctly reflected input cfDNA amount (R2 = 0.910, P = 7.82 × 10−52), implying accuracy of this assay. We found that plasma telomeric cfDNA levels decreased with age in healthy individuals (n = 42, R2 = 0.094, P = 0.048), suggesting that cfDNA is likely derived from somatic cells in which telomere length shortens with increasing age. Our results also showed a significant decrease in telomeric cfDNA level from breast cancer patients with no prior treatment (n = 47), compared to control individuals (n = 42) (P = 4.06 × 10−8). The sensitivity and specificity for the telomeric cfDNA qPCR assay was 91.49% and 76.19%, respectively. Furthermore, the telomeric cfDNA level distinguished even the Ductal Carcinoma In Situ (DCIS) group (n = 7) from the healthy group (n = 42) (P = 1.51 × 10−3). Taken together, decreasing plasma telomeric cfDNA levels could be an informative genetic biomarker for early breast cancer detection. PMID:26356673

  16. Aberrant gene expression patterns in placentomes are associated with phenotypically normal and abnormal cattle cloned by somatic cell nuclear transfer.

    PubMed

    Everts, Robin E; Chavatte-Palmer, Pascale; Razzak, Anthony; Hue, Isabelle; Green, Cheryl A; Oliveira, Rosane; Vignon, Xavier; Rodriguez-Zas, Sandra L; Tian, X Cindy; Yang, Xiangzhong; Renard, Jean-Paul; Lewin, Harris A

    2008-03-14

    Transcription profiling of placentomes derived from somatic cell nuclear transfer (SCNT, n = 20), in vitro fertilization (IVF, n = 9), and artificial insemination (AI, n = 9) at or near term development was performed to better understand why SCNT and IVF often result in placental defects, hydrops, and large offspring syndrome (LOS). Multivariate analysis of variance was used to distinguish the effects of SCNT, IVF, and AI on gene expression, taking into account the effects of parturition (term or preterm), sex of fetus, breed of dam, breed of fetus, and pathological finding in the offspring (hydrops, normal, or other abnormalities). Differential expression of 20 physiologically important genes was confirmed with quantitative PCR. The largest effect on placentome gene expression was attributable to whether placentas were collected at term or preterm (i.e., whether the collection was because of disease or to obtain stage-matched controls) followed by placentome source (AI, IVF, or SCNT). Gene expression in SCNT placentomes was dramatically different from AI (n = 336 genes; 276 >2-fold) and from IVF (n = 733 genes; 162 >2-fold) placentomes. Functional analysis of differentially expressed genes (DEG) showed that IVF has significant effects on genes associated with cellular metabolism. In contrast, DEG associated with SCNT are involved in multiple pathways, including cell cycle, cell death, and gene expression. Many DEG were shared between the gene lists for IVF and SCNT comparisons, suggesting that common pathways are affected by the embryo culture methods used for IVF and SCNT. However, the many unique gene functions and pathways affected by SCNT suggest that cloned fetuses may be starved and accumulating toxic wastes due to placental insufficiency caused by reprogramming errors. Many of these genes are candidates for hydrops and LOS.

  17. Noncoding RNA Expression Aberration Is Associated with Cancer Progression and Is a Potential Biomarker in Esophageal Squamous Cell Carcinoma.

    PubMed

    Sugihara, Hidetaka; Ishimoto, Takatsugu; Miyake, Keisuke; Izumi, Daisuke; Baba, Yoshifumi; Yoshida, Naoya; Watanabe, Masayuki; Baba, Hideo

    2015-11-24

    Esophageal cancer is one of the most common cancers worldwide. Esophageal squamous cell carcinoma (ESCC) is the major histological type of esophageal cancer in Eastern Asian countries. Several types of noncoding RNAs (ncRNAs) function as key epigenetic regulators of gene expression and are implicated in various physiological processes. Unambiguous evidence indicates that dysregulation of ncRNAs is deeply implicated in carcinogenesis, cancer progression and metastases of various cancers, including ESCC. The current review summarizes recent findings on the ncRNA-mediated mechanisms underlying the characteristic behaviors of ESCC that will help support the development of biomarkers and the design of novel therapeutic strategies.

  18. Germline mutations in the VHL tumor suppresssor gene are similar to somatic VHL aberrations in sporadic renal cell carcinoma

    SciTech Connect

    Whaley, J.M.; Naglich, J.; Gelbert, L.

    1994-09-01

    A candidate gene for von Hippel Lindau disease was recently identified that led to the isolation of a partial cDNA clone with extended open reading frame without significant homology to known genes or obvious functional motifs, except for an acidic pentamer repeat domain. To further characterize the functional domains of the VHL gene and assess its involvement in hereditary and non-hereditary tumors, we performed mutation analyses and studied its expresssion in normal and tumor tissue. We identified germline mutations in 39% of VHL disease families. Moreover, 33% of sporadic RCCs, and all (6/6) sporadic RCC cell lines analyzed, showed mutations within the VHL gene. Both germline and somatic mutations included deletions, insertions, splice site mutations, missense and nonsense mutations, all of which clustered at the 3{prime} end of the corresponding partial VHL cDNA open reading frame including an alternatively-spliced exon of 123 nucleotides in length, suggesting functionally important domains encoded by the VHL gene in this region. Over 180 sporadic tumors of other types have shown no detectable base changes within the presumed coding sequence of the VHL gene to date. We conclude that the gene causing VHL has an important and specific role in the etiology of sporadic renal cell carcinomas, acts as a recessive tumor suppressor gene, and appears to encode important functional domains within the 3{prime} end of the known open reading frame.

  19. Hereditary leiomyomatosis and renal cell carcinoma syndrome-associated renal cancer: recognition of the syndrome by pathologic features and the utility of detecting aberrant succination by immunohistochemistry.

    PubMed

    Chen, Ying-Bei; Brannon, A Rose; Toubaji, Antoun; Dudas, Maria E; Won, Helen H; Al-Ahmadie, Hikmat A; Fine, Samson W; Gopalan, Anuradha; Frizzell, Norma; Voss, Martin H; Russo, Paul; Berger, Michael F; Tickoo, Satish K; Reuter, Victor E

    2014-05-01

    Hereditary leiomyomatosis and renal cell carcinoma (HLRCC) syndrome is an autosomal dominant disorder in which germline mutations of fumarate hydratase (FH) gene confer an increased risk of cutaneous and uterine leiomyomas and renal cancer. HLRCC-associated renal cancer is highly aggressive and frequently presents as a solitary mass. We reviewed the clinicopathologic features of 9 patients with renal tumors presenting as sporadic cases but who were later proven to have FH germline mutations. Histologically, all tumors showed mixed architectural patterns, with papillary as the dominant pattern in only 3 cases. Besides papillary, tubular, tubulopapillary, solid, and cystic elements, 6 of 9 tumors contained collecting duct carcinoma-like areas with infiltrating tubules, nests, or individual cells surrounded by desmoplastic stroma. Prominent tubulocystic carcinoma-like component and sarcomatoid differentiation were identified. Although all tumors exhibited the proposed hallmark of HLRCC (large eosinophilic nucleolus surrounded by a clear halo), this feature was often not uniformly present throughout the tumor. Prior studies have shown that a high level of fumarate accumulated in HLRCC tumor cells causes aberrant succination of cellular proteins by forming a stable chemical modification, S-(2-succino)-cysteine (2SC), which can be detected by immunohistochemistry. We thus explored the utility of detecting 2SC by immunohistochemistry in the differential diagnosis of HLRCC tumors and other high-grade renal tumors and investigated the correlation between 2SC staining and FH molecular alterations. All confirmed HLRCC tumors demonstrated diffuse and strong nuclear and cytoplasmic 2SC staining, whereas all clear cell (184/184, 100%), most high-grade unclassified (93/97, 96%), and the large majority of "type 2" papillary (35/45, 78%) renal cell carcinoma cases showed no 2SC immunoreactivity. A subset of papillary (22%) and rare unclassified (4%) tumors showed patchy or diffuse

  20. Chromosome aberrations among the Yanomamma Indians.

    PubMed

    Bloom, A D; Neel, J V; Choi, K W; Iida, S; Chagnon, N

    1970-07-01

    The chromosomes of leucocytes cultured from the peripheral blood of 49 primitive Yanomama Indians of Venezuela were studied to determine the types and frequencies of aberrations in a human population not exposed to the same exogenous agents as civilized man. In all but one instance, 100 cells per individual were scored. In 13 cases, we found one or more cells with multiple complex breaks and rearrangements, represented by tetracentric, tricentric, and numerous dicentric chromosomes. From the standpoint of chromosomal damage, these cells are among the most abnormal cells yet described in vivo in man, and were not seen in the controls. There was also a higher than expected frequency of cells with an isolated structural aberration in both Indians and controls. This may be the result of a 24- to 48-hour delay in the initiation of culture. The cause of the more extensive damage to some cells remains to be determined.

  1. Relative biological effectiveness of 25 and 10 kV X-rays for the induction of chromosomal aberrations in two human mammary epithelial cell lines.

    PubMed

    Beyreuther, Elke; Dörr, Wolfgang; Lehnert, Anna; Lessmann, Elisabeth; Pawelke, Jörg

    2009-08-01

    Administration of ionizing radiation for diagnostic purposes can be associated with a risk for the induction of tumors. Therefore, particularly with regard to general screening programs, e.g. with mammography, cost-benefit considerations must be discussed including risk estimation depending upon the radiation quality administered. The present study was initiated to investigate the in vitro X-ray energy dependence for the induction of chromosomal aberrations in the two mammary epithelial cell lines, 184A1 and MCF-12A. The induced excess fragments, dicentric chromosomes and centric rings were analyzed and the relative biological effectiveness (RBE) was determined for 10 and 25 kV X-rays relative to 200 kV X-rays. The assumed energy dependence with higher values for 10 kV X-rays was confirmed for the excess fragments, with RBE(M) values of 1.92 +/- 0.26 and 1.40 +/- 0.12 for 10 kV X-rays and 1.17 +/- 0.12 and 0.97 +/- 0.10 for 25 kV photons determined for cell lines 184A1 and MCF-12A, respectively. Meaningful results for the induction of dicentric chromosomes and centric rings were obtained only for higher doses with RBE values of 1.31 +/- 0.21 and 1.70 +/- 0.29 for 184A1 and 1.08 +/- 0.08 and 1.43 +/- 0.12 for MCF-12A irradiated with 25 and 10 kV X-rays, respectively.

  2. Simultaneous aberrations of single CDKN2A network components and a high Rb phosphorylation status can differentiate subgroups of primary cutaneous B-cell lymphomas.

    PubMed

    Kaune, Kjell M; Neumann, Christine; Hallermann, Christian; Haller, Florian; Schön, Michael P; Middel, Peter

    2011-04-01

    The cyclin-dependent kinase inhibitor 2A (CDKN2A) gene on chromosome 9p21 encodes p16 (INK4A), the inhibitor of the CDK4/retinoblastoma (Rb) cell proliferation pathway, as well as p14 (ARF), which controls p53-dependent pathways. Inactivation of p16 has previously been associated with the prognostically unfavourable primary cutaneous diffuse large B-cell lymphoma, leg type (PCLBCL, LT). In this work, we analysed 22 tumors [nine primary cutaneous follicle centre lymphomas (PCFCL), seven primary cutaneous marginal zone lymphomas (PCMZL) and six PCLBCL, LT] not only for alterations of the p16 gene but also for p14, p53 and Rb by fluorescence in situ hybridization (FISH) and immunohistochemistry. In most PCLBCL, LT (4/6) alterations of CDKN2A (two biallelic deletions, one monoallelic deletion and one trisomy 9) and in addition the highest frequency of deletions of p53 (3/6) and Rb (3/6) were detected. p16 was not expressed but very high levels of phosphorylated Rb, indicating a functional effect of genomic CDKN2A alterations on the protein level in PCLBCL, LT. Regarding the p14/p53 axis, PCLBCL, LT showed a variable expression. Neither PCFCL nor PCMZL showed alterations of CDKN2A and also deletions of p53 or Rb were extremely rare in these subtypes. Exclusively in PCMZL, p53 protein was consistently lacking. In conclusion, only PCLBCL, LT is characterized by a high frequency of aberrations of the CDKN2A network components in both important tumor suppressor pathways regulated by the CDKN2A gene. Moreover, PCLBCL, LT appears to be distinguishable from PCMZL not only by its level of p53 expression but also by its stage of Rb phosphorylation. The latter may also apply to a subgroup of PCFCL. PMID:21410763

  3. Fibroblast growth factor 8 increases breast cancer cell growth by promoting cell cycle progression and by protecting against cell death

    SciTech Connect

    Nilsson, Emeli M.; Brokken, Leon J.S.; Haerkoenen, Pirkko L.

    2010-03-10

    Fibroblast growth factor 8 (FGF-8) is expressed in a large proportion of breast cancers, whereas its level in normal mammary gland epithelium is low. Previous studies have shown that FGF-8b stimulates breast cancer cell growth in vitro and in vivo. To explore the mechanisms by which FGF-8b promotes growth, we studied its effects on cell cycle regulatory proteins and signalling pathways in mouse S115 and human MCF-7 breast cancer cells. We also studied the effect of FGF-8b on cell survival. FGF-8b induced cell cycle progression and up-regulated particularly cyclin D1 mRNA and protein in S115 cells. Silencing cyclin D1 with siRNA inhibited most but not all FGF-8b-induced proliferation. Inhibition of the FGF-8b-activated ERK/MAPK pathway decreased FGF-8b-stimulated proliferation. Blocking the constitutively active PI3K/Akt and p38 MAPK pathways also lowered FGF-8b-induced cyclin D1 expression and proliferation. Corresponding results were obtained in MCF-7 cells. In S115 and MCF-7 mouse tumours, FGF-8b increased cyclin D1 and Ki67 levels. Moreover, FGF-8b opposed staurosporine-induced S115 cell death which effect was blocked by inhibiting the PI3K/Akt pathway but not the ERK/MAPK pathway. In conclusion, our results suggest that FGF-8b increases breast cancer cell growth both by stimulating cell cycle progression and by protecting against cell death.

  4. Phase from chromatic aberrations.

    PubMed

    Waller, Laura; Kou, Shan Shan; Sheppard, Colin J R; Barbastathis, George

    2010-10-25

    We show that phase objects may be computed accurately from a single color image in a brightfield microscope, with no hardware modification. Our technique uses the chromatic aberration that is inherent to every lens-based imaging system as a phase contrast mechanism. This leads to a simple and inexpensive way of achieving single-shot quantitative phase recovery by a modified Transport of Intensity Equation (TIE) solution, allowing real-time phase imaging in a traditional microscope. PMID:21164620

  5. Chromosomal aberrations in oral solitary fibrous tumor.

    PubMed

    Manor, Esther; Bodner, Lipa

    2007-04-15

    The results of cytogenetic analysis of a solitary fibrous tumor (SFT) of the oral cavity in a 43-year-old man is reported. The abnormal cells carried a complex translocation with the karyotype 46,XY [15 cells]/46,XYt(1;17;18)(p13;q11.2;q21)[5 cells]. This is the first case reporting chromosomal aberrations in an oral SFT.

  6. The endocrine dyscrasia that accompanies menopause and andropause induces aberrant cell cycle signaling that triggers re-entry of post-mitotic neurons into the cell cycle, neurodysfunction, neurodegeneration and cognitive disease.

    PubMed

    Atwood, Craig S; Bowen, Richard L

    2015-11-01

    This article is part of a Special Issue "SBN 2014". Sex hormones are physiological factors that promote neurogenesis during embryonic and fetal development. During childhood and adulthood these hormones support the maintenance of brain structure and function via neurogenesis and the formation of dendritic spines, axons and synapses required for the capture, processing and retrieval of information (memories). Not surprisingly, changes in these reproductive hormones that occur with menopause and during andropause are strongly correlated with neurodegeneration and cognitive decline. In this connection, much evidence now indicates that Alzheimer's disease (AD) involves aberrant re-entry of post-mitotic neurons into the cell cycle. Cell cycle abnormalities appear very early in the disease, prior to the appearance of plaques and tangles, and explain the biochemical, neuropathological and cognitive changes observed with disease progression. Intriguingly, a recent animal study has demonstrated that induction of adult neurogenesis results in the loss of previously encoded memories while decreasing neurogenesis after memory formation during infancy mitigated forgetting. Here we review the biochemical, epidemiological and clinical evidence that alterations in sex hormone signaling associated with menopause and andropause drive the aberrant re-entry of post-mitotic neurons into an abortive cell cycle that leads to neurite retraction, neuron dysfunction and neuron death. When the reproductive axis is in balance, gonadotropins such as luteinizing hormone (LH), and its fetal homolog, human chorionic gonadotropin (hCG), promote pluripotent human and totipotent murine embryonic stem cell and neuron proliferation. However, strong evidence supports menopausal/andropausal elevations in the LH:sex steroid ratio as driving aberrant mitotic events. These include the upregulation of tumor necrosis factor; amyloid-β precursor protein processing towards the production of mitogenic Aβ; and

  7. VHL Induces Renal Cell Differentiation and Growth Arrest through Integration of Cell-Cell and Cell-Extracellular Matrix Signaling

    PubMed Central

    Davidowitz, Eliot J.; Schoenfeld, Alan R.; Burk, Robert D.

    2001-01-01

    Mutations in the von Hippel-Lindau (VHL) gene are involved in the family cancer syndrome for which it is named and the development of sporadic renal cell cancer (RCC). Reintroduction of VHL into RCC cells lacking functional VHL [VHL(−)] can suppress their growth in nude mice, but not under standard tissue culture conditions. To examine the hypothesis that the tumor suppressor function of VHL requires signaling through contact with extracellular matrix (ECM), 786-O VHL(−) RCC cells and isogenic sublines stably expressing VHL gene products [VHL(+)] were grown on ECMs. Cell-cell and cell-ECM signalings were required to elicit VHL-dependent differences in growth and differentiation. VHL(+) cells differentiated into organized epithelial sheets, whereas VHL(−) cells were branched and disorganized. VHL(+) cells grown to high density on collagen I underwent growth arrest, whereas VHL(−) cells continued to proliferate. Integrin levels were up-regulated in VHL(−) cells, and cell adhesion was down-regulated in VHL(+) cells during growth at high cell density. Hepatocyte nuclear factor 1α, a transcription factor and global activator of proximal tubule-specific genes in the nephron, was markedly up-regulated in VHL(+) cells grown at high cell density. These data indicate that VHL can induce renal cell differentiation and mediate growth arrest through integration of cell-cell and cell-ECM signals. PMID:11154273

  8. Cell Wall Nonlinear Elasticity and Growth Dynamics: How Do Bacterial Cells Regulate Pressure and Growth?

    NASA Astrophysics Data System (ADS)

    Deng, Yi

    In my thesis, I study intact and bulging Escherichia coli cells using atomic force microscopy to separate the contributions of the cell wall and turgor pressure to the overall cell stiffness. I find strong evidence of power--law stress--stiffening in the E. coli cell wall, with an exponent of 1.22±0.12, such that the wall is significantly stiffer in intact cells (E = 23±8 MPa and 49±20 MPa in the axial and circumferential directions) than in unpressurized sacculi. These measurements also indicate that the turgor pressure in living cells E. coli is 29±3 kPa. The nonlinearity in cell elasticity serves as a plausible mechanism to balance the mechanical protection and tension measurement sensitivity of the cell envelope. I also study the growth dynamics of the Bacillus subtilis cell wall to help understand the mechanism of the spatiotemporal order of inserting new cell wall material. High density fluorescent markers are used to label the entire cell surface to capture the morphological changes of the cell surface at sub-cellular to diffraction-limited spatial resolution and sub-minute temporal resolution. This approach reveals that rod-shaped chaining B. subtilis cells grow and twist in a highly heterogeneous fashion both spatially and temporally. Regions of high growth and twisting activity have a typical length scale of 5 μm, and last for 10-40 minutes. Motivated by the quantification of the cell wall growth dynamics, two microscopy and image analysis techniques are developed and applied to broader applications beyond resolving bacterial growth. To resolve densely distributed quantum dots, we present a fast and efficient image analysis algorithm, namely Spatial Covariance Reconstruction (SCORE) microscopy that takes into account the blinking statistics of the fluorescence emitters. We achieve sub-diffraction lateral resolution of 100 nm from 5 to 7 seconds of imaging, which is at least an order of magnitude faster than single-particle localization based methods

  9. Trisomy 18: studies of the parent and cell division of origin and the effect of aberrant recombination on nondisjunction.

    PubMed Central

    Fisher, J M; Harvey, J F; Morton, N E; Jacobs, P A

    1995-01-01

    We have studied the mechanism of origin of 63 cases of trisomy 18. In 2 the additional chromosome was paternal in origin, and in the remaining 61 it was maternal in origin. Both paternal cases were attributable to a postzygotic mitotic (PZM) error. Among the 54 maternal cases for which the cell division of error was established, only 16 were attributable to an error at the first meiotic division (mat MI), whereas no fewer than 35 were due to an error at the second meiotic division (mat MII), the remaining 3 being the result of a PZM error involving the maternal chromosome 18. A standard map of chromosome 18 was constructed and compared with the nondisjunctional map. Approximately one-third of the mat MI errors were associated with complete absence of recombination, whereas in the remaining two-thirds and in all the mat MII errors recombination in the nondisjoined chromosomes appeared to be normal. All the maternal errors were associated with an increased maternal age, although this reached significance only for the mat MII category of nondisjunction. Our observations on chromosome 18 are compared with those on other chromosomes for which there are comparable data. PMID:7887421

  10. Trisomy 18: studies of the parent and cell division of origin and the effect of aberrant recombination on nondisjunction

    SciTech Connect

    Fisher, J.M.; Harvey, J.F.; Jacobs, P.A.; Morton, N.E.

    1995-03-01

    We have studied the mechanism of origin of 63 cases of trisomy 18. In 2 the additional chromosome was paternal in origin, and in the remaining 61 it was maternal in origin. Both paternal cases were attributable to a postzygotic mitotic (PZM) error. Among the 54 maternal cases for which the cell division of error was established, only 16 were attributable to an error at the first meiotic division (mat MI), whereas no fewer than 35 were due an error at the second meiotic division (mat MII), the remaining 3 being the result of a PZM error involving the maternal chromosome 18. A standard map of chromosome 18 was constructed and compared with the nondisjunctional map. Approximately one-third of the mat MI errors were associated with complete absence of recombination, whereas in the remaining two-thirds and in all the mat MII errors recombination in the nondisjoined chromosomes appeared to be normal. All the maternal errors were associated with an increased maternal age, although this reached significance only for the mat MII category of nondisjunction. Our observations on chromosome 18 are compared with those on other chromosomes for which there are comparable data. 37 refs., 7 tabs.

  11. Cell growth on immobilized cell growth factor. 8. Protein-free cell culture on insulin-immobilized microcarriers.

    PubMed

    Ito, Y; Uno, T; Liu, S Q; Imanishi, Y

    1992-12-01

    In order to develop a new protein-free cell culture system, microcarriers immobilized with insulin were synthesized. For the synthesis, glass and polyacrylamide beads were treated for the introduction of amino groups on the surface, and insulin was immobilized on the surface by using several method. Anchorage-dependent cells. mouse fibroblast cells STO and fibroic sarcoma cells HSDM(1)C(1), and the anchorage-independent cells, mouse hybridoma cells SJK132-20 and RDP 45/20 were cultivated on the microcarriers immobilized with insulin. The insulin-immobilized microcarriers did not have any effect on the proliferation of the anchorage independent cells but promoted the growth of anchorage-dependent cells remarkably. The activity of immobilized insulin was larger than that of free or adsorbed insulin. The repeated use of the insulin-immobilized microcarrier was possible, and the promotion activity in the the repeated use was greater than that in the use.

  12. Automated quantification of FISH signals in urinary cells enables the assessment of chromosomal aberration patterns characteristic for bladder cancer.

    PubMed

    Köhler, Christina U; Martin, Laura; Bonberg, Nadine; Behrens, Thomas; Deix, Thomas; Braun, Katharina; Noldus, Joachim; Jöckel, Karl-Heinz; Erbel, Raimund; Sommerer, Florian; Tannapfel, Andrea; Harth, Volker; Käfferlein, Heiko U; Brüning, Thomas

    2014-06-13

    Targeting the centromeres of chromosomes 3, 7, 17 (CEP3, 7, 17) and the 9p21-locus (LSI9p21) for diagnosing bladder cancer (BC) is time- and cost-intensive and requires a manual investigation of the sample by a well-trained investigator thus overall limiting its use in clinical diagnostics and large-scaled epidemiological studies. Here we introduce a new computer-assisted FISH spot analysis tool enabling an automated, objective and quantitative assessment of FISH patterns in the urinary sediment. Utilizing a controllable microscope workstation, the microscope software Scan^R was programmed to allow automatic batch-scanning of up to 32 samples and identifying quadruple FISH signals in DAPI-scanned nuclei of urinary sediments. The assay allowed a time- and cost-efficient, automated and objective assessment of CEP3, 7 and 17 FISH signals and facilitated the quantification of nuclei harboring specific FISH patterns in all cells of the urinary sediment. To explore the diagnostic capability of the developed tool, we analyzed the abundance of 51 different FISH patterns in a pilot set of urine specimens from 14 patients with BC and 21 population controls (PC). Herein, the results of the fully automated approach yielded a high degree of conformity when compared to those obtained by an expert-guided re-evaluation of archived scans. The best cancer-identifying pattern was characterized by a concurrent gain of CEP3, 7 and 17. Overall, our automated analysis refines current FISH protocols and encourages its use to establish reliable diagnostic cutoffs in future large-scale studies with well-characterized specimens-collectives. PMID:24802410

  13. Xyloglucan Deficiency Disrupts Microtubule Stability and Cellulose Biosynthesis in Arabidopsis, Altering Cell Growth and Morphogenesis.

    PubMed

    Xiao, Chaowen; Zhang, Tian; Zheng, Yunzhen; Cosgrove, Daniel J; Anderson, Charles T

    2016-01-01

    Xyloglucan constitutes most of the hemicellulose in eudicot primary cell walls and functions in cell wall structure and mechanics. Although Arabidopsis (Arabidopsis thaliana) xxt1 xxt2 mutants lacking detectable xyloglucan are viable, they display growth defects that are suggestive of alterations in wall integrity. To probe the mechanisms underlying these defects, we analyzed cellulose arrangement, microtubule patterning and dynamics, microtubule- and wall-integrity-related gene expression, and cellulose biosynthesis in xxt1 xxt2 plants. We found that cellulose is highly aligned in xxt1 xxt2 cell walls, that its three-dimensional distribution is altered, and that microtubule patterning and stability are aberrant in etiolated xxt1 xxt2 hypocotyls. We also found that the expression levels of microtubule-associated genes, such as MAP70-5 and CLASP, and receptor genes, such as HERK1 and WAK1, were changed in xxt1 xxt2 plants and that cellulose synthase motility is reduced in xxt1 xxt2 cells, corresponding with a reduction in cellulose content. Our results indicate that loss of xyloglucan affects both the stability of the microtubule cytoskeleton and the production and patterning of cellulose in primary cell walls. These findings establish, to our knowledge, new links between wall integrity, cytoskeletal dynamics, and wall synthesis in the regulation of plant morphogenesis.

  14. Regulation of human amnion cell growth and morphology by sera, plasma, and growth factors.

    PubMed

    Gaffney, E V; Grimaldi, M A

    1981-01-01

    The requirements of human epithelial cells derived from the amnion membrane for serum factors were investigated. The growth promoting effects of human whole blood serum (WBS), platelet-poor defibrinogenated plasma, and plasma-derived serum (PDS) were examined in primary cultures of these ectodermal cells. The numbers of population doublings recorded after 10 days in the presence of 10% WBS, defibrinogenated plasma, or PDS were 2.3, 2.0 or 1.5, respectively. Although dialysis of sera or plasma had little effect on growth promotion, it markedly decreased the capacity of plasma to maintain cells in culture beyond 10 days. The differences in growth activities could not be attributed to the presence of anticoagulant in plasma and PDS or to the presence of excess calcium in PDS. Platelet lysates and purified platelet-derived growth factor had no effect on growth. Amnion cell growth was enhanced by epidermal growth factor (EGF) or hydrocortisone, but the glucocorticoid did not condition cells to respond to growth factors. Insulin and fibroblast growth factor singly or in combination had no effect on cell replication. Giant cell formation accompanied maintenance in hydrocortisone with defibrinogenated plasma and PDS. Discrete regions of dense population appeared in the presence of hydrocortisone, EGF, and undialyzed supplements.

  15. The influence of internally deposited alpha ({sup 239}Pu) or beta-gamma ({sup 144}Ce) emitting radionuclides on the sensitivity of Chinese hamster bone marrow cells to {sup 60}CO induced chromosome aberrations

    SciTech Connect

    Brooks, A.L.; McDonald, K.E.; Kitchin, R.M.

    1994-12-31

    The current study was designed to determine if protracted low-dose-rate exposures from either high-({sup 239}Pu) or low-({sup 144}Ce) LET radiation from internally deposited radioactive materials changes the frequency of chromosome aberrations induced by acute {sup 60}Co exposure. THe potential for interaction was evaluated 30 days after injection with either 0 or 0.85 kBq {sup 144}Ce g{sup -1} body weight or 0.0 or 2.2 Bq of {sup 239}Pu g{sup -1}. Injection with {sup 239}Pu or {sup 144}Ce resulted in few aberrations in bone marrow cells 30 days after injection. The presence of internally deposited {sup 239}Pu or {sup 144}Ce did not significantly alter the total frequency of {sup 60}Co induced aberrations. However, the frequency of {sup 60}Co induced chromatid exchanges was significantly greater (P=0.03) in bone marrow cells of animals with {sup 144}Ce body burdens (0.14{+-}0.03 chromatid exchanges/cell). Such data illustrates that changes in cellular responsiveness may be dependent on the LET of the isotope, the dose rate of the primary dose and the type of damage being evaluated.

  16. Autocrine growth factors for human tumor clonogenic cells.

    PubMed

    Hamburger, A W; White, C P

    1985-11-01

    A human epithelial-derived cell line, SW-13, releases a soluble substance that functions as an autocrine growth factor. SW-13 cells, derived from a human adenocarcinoma of the adrenal cortex, form a few small colonies when suspended in soft agar at low densities. The number of colonies increased significantly when either viable SW-13 cells or serum-free medium conditioned by SW-13 cells (CM) was added to agar underlayers. CM increased colony formation in a dose-dependent fashion. Clonal growth at low cell densities was dependent on the presence of both horse serum and SW-13 CM. Neither activity alone was capable of sustaining growth. Even when cells were plated at high densities CM could not substitute for serum, but could reduce the threshold serum concentration. The results suggest that autocrine and serum-derived factors act in concert to maintain clonal growth of epithelial tumor cells in soft agar.

  17. Metabolic flux and the regulation of mammalian cell growth

    PubMed Central

    Locasale, Jason W.; Cantley, Lewis C.

    2011-01-01

    The study of normal mammalian cell growth and the defects that contribute to disease pathogenesis constitutes a fundamental avenue of research that links metabolism to cell growth. Here we visit several aspects of this metabolism, emphasizing recent advances in our understanding of how alterations in glucose metabolism affect cytosolic and mitochondrial redox potential and ATP generation. These alterations drive cell growth not only through supporting biosynthesis, energy metabolism, and maintaining redox potential but also through initiating signaling mechanisms that are still poorly characterized. The evolutionary basis of these additional layers of growth control is also discussed. PMID:21982705

  18. Cooperative nutrient accumulation sustains growth of mammalian cells.

    PubMed

    Son, Sungmin; Stevens, Mark M; Chao, Hui Xiao; Thoreen, Carson; Hosios, Aaron M; Schweitzer, Lawrence D; Weng, Yaochung; Wood, Kris; Sabatini, David; Vander Heiden, Matthew G; Manalis, Scott

    2015-01-01

    The coordination of metabolic processes to allow increased nutrient uptake and utilization for macromolecular synthesis is central for cell growth. Although studies of bulk cell populations have revealed important metabolic and signaling requirements that impact cell growth on long time scales, whether the same regulation influences short-term cell growth remains an open question. Here we investigate cell growth by monitoring mass accumulation of mammalian cells while rapidly depleting particular nutrients. Within minutes following the depletion of glucose or glutamine, we observe a growth reduction that is larger than the mass accumulation rate of the nutrient. This indicates that if one particular nutrient is depleted, the cell rapidly adjusts the amount that other nutrients are accumulated, which is consistent with cooperative nutrient accumulation. Population measurements of nutrient sensing pathways involving mTOR, AKT, ERK, PKA, MST1, or AMPK, or pro-survival pathways involving autophagy suggest that they do not mediate this growth reduction. Furthermore, the protein synthesis rate does not change proportionally to the mass accumulation rate over these time scales, suggesting that intracellular metabolic pools buffer the growth response. Our findings demonstrate that cell growth can be regulated over much shorter time scales than previously appreciated. PMID:26620632

  19. Aberrant phenotypes in Kikuchi’s disease

    PubMed Central

    Wei, Xue-Jing; Zhou, Xiao-Ge; Xie, Jian-Lan; Zheng, Xiao-Dan; Zheng, Yuan-Yuan

    2014-01-01

    Initial reports emphasized the immunophenotypic similarities between benign and malignant T cell populations, while some previous studies indicating that aberrant T-cell antigen loss is a good marker for detecting malignant T-cell proliferation. Recently, we found a very interesting and thought-provoking phenomenon: In benign disease-28 of 38 (73.7%) cases of Kikuchi’s disease also showed aberrant phenotypes with loss of pan-T cell antigens, which makes the differential diagnosis between Kikuchi’s disease and T cell lymphoma more challenging. In our study, 38 cases of Kikuchi’s disease and 30 cases of reactive lymphoid hyperplasia (RLH) were studied by EliVision immunohistochemical staining. As well as TCR gene rearrangement using PCR was negative in 10 tested cases of the Kikuchi’s disease. Among these cases, the most common antigen deficiency was CD5 (22 cases), then CD7 (11 cases), CD2 (8 cases) and CD3 (2 cases). Compared with proliferative and xanthomatous types of Kikuchi’s disease, antigens tended to be lost in necrotizing type. Based on follow-up data, a correlation was not found between the occurrence of aberrant phenotypes and prognosis. In RLH, obvious pan-T cell antigen loss was also not found. In conclusion, this is the first study to demonstrate distinct patterns of antigen loss in Kikuchi’s disease, suggesting that T cell antigen loss is not reliable as an auxiliary diagnostic standard for T cell lymphoma. PMID:25337197

  20. Aberrant glycosylation associated with enzymes as cancer biomarkers

    PubMed Central

    2011-01-01

    Background One of the new roles for enzymes in personalized medicine builds on a rational approach to cancer biomarker discovery using enzyme-associated aberrant glycosylation. A hallmark of cancer, aberrant glycosylation is associated with differential expressions of enzymes such as glycosyltransferase and glycosidases. The aberrant expressions of the enzymes in turn cause cancer cells to produce glycoproteins with specific cancer-associated aberrations in glycan structures. Content In this review we provide examples of cancer biomarker discovery using aberrant glycosylation in three areas. First, changes in glycosylation machinery such as glycosyltransferases/glycosidases could be used as cancer biomarkers. Second, most of the clinically useful cancer biomarkers are glycoproteins. Discovery of specific cancer-associated aberrations in glycan structures of these existing biomarkers could improve their cancer specificity, such as the discovery of AFP-L3, fucosylated glycoforms of AFP. Third, cancer-associated aberrations in glycan structures provide a compelling rationale for discovering new biomarkers using glycomic and glycoproteomic technologies. Summary As a hallmark of cancer, aberrant glycosylation allows for the rational design of biomarker discovery efforts. But more important, we need to translate these biomarkers from discovery to clinical diagnostics using good strategies, such as the lessons learned from translating the biomarkers discovered using proteomic technologies to OVA 1, the first FDA-cleared In Vitro Diagnostic Multivariate Index Assay (IVDMIA). These lessons, providing important guidance in current efforts in biomarker discovery and translation, are applicable to the discovery of aberrant glycosylation associated with enzymes as cancer biomarkers as well. PMID:21906357

  1. DNA Repair Defects and Chromosomal Aberrations

    NASA Technical Reports Server (NTRS)

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

    2009-01-01

    Yields of chromosome aberrations were assessed in cells deficient in DNA doublestrand break (DSB) repair, after exposure to acute or to low-dose-rate (0.018 Gy/hr) gamma rays or acute high LET iron nuclei. We studied several cell lines including fibroblasts deficient in ATM (ataxia telangiectasia mutated; product of the gene that is mutated in ataxia telangiectasia patients) or NBS (nibrin; product of the gene mutated in the Nijmegen breakage syndrome), and gliomablastoma cells that are proficient or lacking in DNA-dependent protein kinase (DNA-PK) activity. Chromosomes were analyzed using the fluorescence in situ hybridization (FISH) chromosome painting method in cells at the first division post irradiation, and chromosome aberrations were identified as either simple exchanges (translocations and dicentrics) or complex exchanges (involving >2 breaks in 2 or more chromosomes). Gamma irradiation induced greater yields of both simple and complex exchanges in the DSB repair-defective cells than in the normal cells. The quadratic dose-response terms for both simple and complex chromosome exchanges were significantly higher for the ATM- and NBS-deficient lines than for normal fibroblasts. However, in the NBS cells the linear dose-response term was significantly higher only for simple exchanges. The large increases in the quadratic dose-response terms in these repair-defective cell lines points the importance of the functions of ATM and NBS in chromatin modifications to facilitate correct DSB repair and minimize the formation of aberrations. The differences found between ATM- and NBS-deficient cells at low doses suggest that important questions should with regard to applying observations of radiation sensitivity at high dose to low-dose exposures. For aberrations induced by iron nuclei, regression models preferred purely linear dose responses for simple exchanges and quadratic dose responses for complex exchanges. Relative biological effectiveness (RBE) factors of all of

  2. Vascular endothelial growth factor B, a novel growth factor for endothelial cells.

    PubMed Central

    Olofsson, B; Pajusola, K; Kaipainen, A; von Euler, G; Joukov, V; Saksela, O; Orpana, A; Pettersson, R F; Alitalo, K; Eriksson, U

    1996-01-01

    We have isolated and characterized a novel growth factor for endothelial cells, vascular endothelial growth factor B (VEGF-B), with structural similarities to vascular endothelial growth factor (VEGF) and placenta growth factor. VEGF-B was particularly abundant in heart and skeletal muscle and was coexpressed with VEGF in these and other tissues. VEGF-B formed cell-surface-associated disulfide-linked homodimers and heterodimerized with VEGF when coexpressed. Conditioned medium from transfected 293EBNA cells expressing VEGF-B stimulated DNA synthesis in endothelial cells. Our results suggest that VEGF-B has a role in angiogenesis and endothelial cell growth, particularly in muscle. Images Fig. 3 Fig. 4 Fig. 5 PMID:8637916

  3. Chemopreventive effect of Amorphophallus campanulatus (Roxb.) blume tuber against aberrant crypt foci and cell proliferation in 1, 2-dimethylhydrazine induced colon carcinogenesis.

    PubMed

    Ansil, Puthuparampil Nazarudeen; Prabha, Santhibhavan Prabhakaran; Nitha, Anand; Latha, Mukalel Sankunni

    2013-01-01

    Colorectal cancer is one of the leading causes of cancer death, both in men and women. This study investigated the effects of Amorphophallus campanulatus tuber methanolic extract (ACME) on aberrant crypt foci (ACF) formation, colonic cell proliferation, lipid peroxidative damage and the antioxidant status in a long term preclinical model of 1, 2-dimethylhydrazine (DMH) induced colon carcinogenesis in rats. Male Wistar rats were divided into six groups, viz., group I rats served as controls; group II rats treated as drug controls receiving 250 mg/ kg body weight of ACME orally; group III rats received DMH (20 mg/kg body weight) subcutaneously once a week for the first 15 weeks; groups IV, V and VI rats received ACME along with DMH during the initiation, post- initiation stages and the entire period of the study, respectively. All the rats were sacrificed at the end of 30 weeks and the intestinal and colonic tissues from different groups were subjected to biochemical and histological studies. Administration of DMH resulted in significant (p ≤ 0.05) intestinal and colonic lipid peroxidation (MDA) and reduction of antioxidants such as catalase, glutathione peroxidase, glutathione reductase, glutathione-S- transferase and reduced glutathione. Whereas the supplementation of ACME significantly (p ≤ 0.05) improved the intestinal and colonic MDA and reduced glutathione levels and the activities of antioxidant enzymes in DMH intoxicated rats. ACME administration also significantly suppressed the formation and multiplicity of ACF. In addition, the DMH administered rats showed amplified expression of PCNA in the colon and decreased expression of this proliferative marker was clearly noted with initiation, post-initiation and entire period of ACME treatment regimens. These results indicate that ACME could exert a significant chemopreventive effect on colon carcinogenesis induced by DMH. PMID:24175821

  4. Late-occurring chromosome aberrations and global DNA methylation in hematopoietic stem/progenitor cells of CBA/CaJ mice exposed to silicon ((28)Si) ions.

    PubMed

    Rithidech, Kanokporn Noy; Honikel, Louise M; Reungpathanaphong, Paiboon; Tungjai, Montree; Jangiam, Witawat; Whorton, Elbert B

    2015-11-01

    Although myeloid leukemia (ML) is one of the major health concerns from exposure to space radiation, the risk prediction for developing ML is unsatisfactory. To increase the reliability of predicting ML risk, a much improved understanding of space radiation-induced changes in the target cells, i.e. hematopoietic stem/progenitor cells (HSPCs), is important. We focused on the in vivo induction of late-occurring damage in HSPCs of mice exposed to (28)Si ions since such damage is associated with radiation-induced genomic instability (a key event of carcinogenesis). We gave adult male CBA/CaJ mice, known to be sensitive to radiation-induced ML, a whole-body exposure (2 fractionated exposures, 15 days apart, that totaled each selected dose, delivered at the dose-rate of 1 cGy/min) to various doses of 300 MeV/n (28)Si ions, i.e. 0 (sham controls), 0.1, 0.25, or 0.5 Gy. At 6 months post-irradiation, we collected bone marrow cells from each mouse (five mice per treatment-group) for obtaining the myeloid-lineage of HSPC-derived clones for analyses. We measured the frequencies of late-occurring chromosome aberrations (CAs), using the genome-wide multicolor fluorescence in situ hybridization method. The measurement of CAs was coupled with the characterization of the global DNA methylation patterns, i.e. 5-methylcytosine (5 mC) and 5-hydroxymethylcytosine (5 hmC). A dose-dependent increase in the frequencies of CAs was detected (Analysis of Variance or ANOVA, p<0.01), indicating the induction of genomic instability after exposure of mice to 300 MeV/n (28)Si ions. Slight increases in the levels of 5 mC were observed in all treatment groups, as compared to the sham-control level. In contrast, there was a significant reduction in levels of 5 hmC (ANOVA, p<0.01). Since these endpoints were evaluated in the same mouse, our data suggested for the first time a link between a reduction in 5 hmC and genomic instability in HSPC-derived myeloid colonies of CBA/CaJ mice exposed to 300 Me

  5. Separating growth from elastic deformation during cell enlargement

    SciTech Connect

    Proseus, T.E.; Boyer, J.S. . Coll. of Marine Studies); Ortega, J.K.E. . Dept. of Mechanical Engineering)

    1999-02-01

    Plants change size by deforming reversibly (elastically) whenever turgor pressure changes, and by growing. The elastic deformation is independent of growth because it occurs in nongrowing cells. Its occurrence with growth has prevented growth from being observed alone. The authors investigated whether the two processes could be separated in internode cells of Chara corallina Klien ex Willd., em R.D.W. by injecting or removing cell solution with a pressure probe to change turgor while the cell length was continuously measured. Cell size changed immediately when turgor changed, and growth rates appeared to be altered. Low temperature eliminated growth but did not alter the elastic effects. This allowed elastic deformation measured at low temperature to be subtracted from elongation at warm temperature in the same cell. After te subtraction, growth alone could be observed for the first time. Alternations in turgor caused growth to change rapidly to a new, steady rate with no evidence of rapid adjustments in wall properties. This turgor response, together with the marked sensitivity of growth to temperature, suggested that the growth rate was not controlled by inert polymer extension but rather by the biochemical reactions that include a turgor-sensitive step.

  6. On the growth of walled cells: From shells to vesicles.

    NASA Astrophysics Data System (ADS)

    Boudaoud, Arezki

    2003-03-01

    The growth of isolated walled cells is investigated. Examples of such cells range from bacteria to giant algae, and include cochlear hair, plant root hair, fungi and yeast cells. They are modeled as elastic shells inflated by a liquid. Cell growth is driven by fluid pressure and is similar to a plastic deformation of the wall. The requirement of mechanical equilibrium leads to two new scaling laws for cell size that are in quantitative agreement with the compiled biological data. Given these results, possible shapes for growing cells are computed by analogy with those of vesicle membranes.

  7. Growth of Walled Cells: From Shells to Vesicles

    NASA Astrophysics Data System (ADS)

    Boudaoud, Arezki

    2003-07-01

    The growth of isolated walled cells is investigated. Examples of such cells range from bacteria to giant algae, and include cochlear hair, plant root hair, fungi, and yeast cells. They are modeled as elastic shells containing a liquid. Cell growth is driven by fluid pressure and is is similar to a plastic deformation of the wall. The requirement of mechanical equilibrium leads to two new scaling laws for cell size that are in quantitative agreement with the compiled biological data. Given these results, possible shapes for growing cells are computed by analogy with those of vesicle membranes.

  8. Cell Competition Drives the Growth of Intestinal Adenomas in Drosophila.

    PubMed

    Suijkerbuijk, Saskia J E; Kolahgar, Golnar; Kucinski, Iwo; Piddini, Eugenia

    2016-02-22

    Tumor-host interactions play an increasingly recognized role in modulating tumor growth. Thus, understanding the nature and impact of this complex bidirectional communication is key to identifying successful anti-cancer strategies. It has been proposed that tumor cells compete with and kill neighboring host tissue to clear space that they can expand into; however, this has not been demonstrated experimentally. Here we use the adult fly intestine to investigate the existence and characterize the role of competitive tumor-host interactions. We show that APC(-/-)-driven intestinal adenomas compete with and kill surrounding cells, causing host tissue attrition. Importantly, we demonstrate that preventing cell competition, by expressing apoptosis inhibitors, restores host tissue growth and contains adenoma expansion, indicating that cell competition is essential for tumor growth. We further show that JNK signaling is activated inside the tumor and in nearby tissue and is required for both tumor growth and cell competition. Lastly, we find that APC(-/-) cells display higher Yorkie (YAP) activity than host cells and that this promotes tumor growth, in part via cell competition. Crucially, we find that relative, rather than absolute, Hippo activity determines adenoma growth. Overall, our data indicate that the intrinsic over-proliferative capacity of APC(-/-) cells is not uncontrolled and can be constrained by host tissues if cell competition is inhibited, suggesting novel possible therapeutic approaches.

  9. Cell Competition Drives the Growth of Intestinal Adenomas in Drosophila

    PubMed Central

    Suijkerbuijk, Saskia J.E.; Kolahgar, Golnar; Kucinski, Iwo; Piddini, Eugenia

    2016-01-01

    Summary Tumor-host interactions play an increasingly recognized role in modulating tumor growth. Thus, understanding the nature and impact of this complex bidirectional communication is key to identifying successful anti-cancer strategies. It has been proposed that tumor cells compete with and kill neighboring host tissue to clear space that they can expand into; however, this has not been demonstrated experimentally. Here we use the adult fly intestine to investigate the existence and characterize the role of competitive tumor-host interactions. We show that APC−/−-driven intestinal adenomas compete with and kill surrounding cells, causing host tissue attrition. Importantly, we demonstrate that preventing cell competition, by expressing apoptosis inhibitors, restores host tissue growth and contains adenoma expansion, indicating that cell competition is essential for tumor growth. We further show that JNK signaling is activated inside the tumor and in nearby tissue and is required for both tumor growth and cell competition. Lastly, we find that APC−/− cells display higher Yorkie (YAP) activity than host cells and that this promotes tumor growth, in part via cell competition. Crucially, we find that relative, rather than absolute, Hippo activity determines adenoma growth. Overall, our data indicate that the intrinsic over-proliferative capacity of APC−/− cells is not uncontrolled and can be constrained by host tissues if cell competition is inhibited, suggesting novel possible therapeutic approaches. PMID:26853366

  10. Growth inhibition of Candida by human oral epithelial cells.

    PubMed

    Steele, C; Leigh, J; Swoboda, R; Fidel, P L

    2000-11-01

    Oropharyngeal candidiasis (OPC) caused by Candida albicans is a significant problem in human immunodeficiency virus (HIV)-infected persons. Recognizing the paucity of information on innate and/or adaptive mucosal host defenses against C. albicans, we recently reported that human and nonhuman primate and mouse vaginal epithelial cells inhibit the growth of C. albicans in vitro. In the present study, oral epithelial cells collected from saliva of healthy volunteers and a purified oral epithelial cell line were found to inhibit blastoconidia and/or hyphal growth of several Candida species. Cell contact was a strict requirement for the epithelial cell anti-Candida activity; neither saliva nor culture supernatants alone inhibited Candida growth, and addition of saliva to the coculture did not modulate the epithelial cell activity. Finally, epithelial cell anti-Candida activity was significantly lower in HIV-infected persons with OPC. Together, these results suggest that oral epithelial cells may play a role in innate resistance against OPC.

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

    PubMed Central

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

    2008-01-01

    The vertebrate lens provides an excellent model to study the mechanisms that regulate terminal differentiation. Although fibroblast growth factors (FGFs) are thought to be important for lens cell differentiation, it is unclear which FGF receptors mediate these processes during different stages of lens development. Deletion of three FGF receptors (Fgfr1-3) early in lens development demonstrated that expression of only a single allele of Fgfr2 or Fgfr3 was sufficient for grossly normal lens development, while mice possessing only a single Fgfr1 allele developed cataracts and microphthalmia. Profound defects were observed in lenses lacking all three Fgfrs. These included lack of fiber cell elongation, abnormal proliferation in prospective lens fiber cells, reduced expression of the cell cycle inhibitors p27kip1 and p57kip2, increased apoptosis and aberrant or reduced expression of Prox1, Pax6, c-Maf, E-cadherin and α-, β- and γ-crystallins. Therefore, while signaling by FGF receptors is essential for lens fiber differentiation, different FGF receptors function redundantly. PMID:18455718

  12. The chemopotential effect of Annona muricata leaves against azoxymethane-induced colonic aberrant crypt foci in rats and the apoptotic effect of Acetogenin Annomuricin E in HT-29 cells: a bioassay-guided approach.

    PubMed

    Zorofchian Moghadamtousi, Soheil; Rouhollahi, Elham; Karimian, Hamed; Fadaeinasab, Mehran; Firoozinia, Mohammad; Ameen Abdulla, Mahmood; Abdul Kadir, Habsah

    2015-01-01

    Annona muricata has been used in folk medicine for the treatment of cancer and tumors. This study evaluated the chemopreventive properties of an ethyl acetate extract of A. muricata leaves (EEAML) on azoxymethane-induced colonic aberrant crypt foci (ACF) in rats. Moreover, the cytotoxic compound of EEAML (Annomuricin E) was isolated, and its apoptosis-inducing effect was investigated against HT-29 colon cancer cell line using a bioassay-guided approach. This experiment was performed on five groups of rats: negative control, cancer control, EEAML (250 mg/kg), EEAML (500 mg/kg) and positive control (5-fluorouracil). Methylene blue staining of colorectal specimens showed that application of EEAML at both doses significantly reduced the colonic ACF formation compared with the cancer control group. Immunohistochemistry analysis showed the down-regulation of PCNA and Bcl-2 proteins and the up-regulation of Bax protein after administration of EEAML compared with the cancer control group. In addition, an increase in the levels of enzymatic antioxidants and a decrease in the malondialdehyde level of the colon tissue homogenates were observed, suggesting the suppression of lipid peroxidation. Annomuricin E inhibited the growth of HT-29 cells with an IC50 value of 1.62 ± 0.24 μg/ml after 48 h. The cytotoxic effect of annomuricin E was further substantiated by G1 cell cycle arrest and early apoptosis induction in HT-29 cells. Annomuricin E triggered mitochondria-initiated events, including the dissipation of the mitochondrial membrane potential and the leakage of cytochrome c from the mitochondria. Prior to these events, annomuricin E activated caspase 3/7 and caspase 9. Upstream, annomuricin E induced a time-dependent upregulation of Bax and downregulation of Bcl-2 at the mRNA and protein levels. In conclusion, these findings substantiate the usage of A. muricata leaves in ethnomedicine against cancer and highlight annomuricin E as one of the contributing compounds in the

  13. The Chemopotential Effect of Annona muricata Leaves against Azoxymethane-Induced Colonic Aberrant Crypt Foci in Rats and the Apoptotic Effect of Acetogenin Annomuricin E in HT-29 Cells: A Bioassay-Guided Approach

    PubMed Central

    Zorofchian Moghadamtousi, Soheil; Rouhollahi, Elham; Karimian, Hamed; Fadaeinasab, Mehran; Firoozinia, Mohammad; Ameen Abdulla, Mahmood; Abdul Kadir, Habsah

    2015-01-01

    Annona muricata has been used in folk medicine for the treatment of cancer and tumors. This study evaluated the chemopreventive properties of an ethyl acetate extract of A. muricata leaves (EEAML) on azoxymethane-induced colonic aberrant crypt foci (ACF) in rats. Moreover, the cytotoxic compound of EEAML (Annomuricin E) was isolated, and its apoptosis-inducing effect was investigated against HT-29 colon cancer cell line using a bioassay-guided approach. This experiment was performed on five groups of rats: negative control, cancer control, EEAML (250 mg/kg), EEAML (500 mg/kg) and positive control (5-fluorouracil). Methylene blue staining of colorectal specimens showed that application of EEAML at both doses significantly reduced the colonic ACF formation compared with the cancer control group. Immunohistochemistry analysis showed the down-regulation of PCNA and Bcl-2 proteins and the up-regulation of Bax protein after administration of EEAML compared with the cancer control group. In addition, an increase in the levels of enzymatic antioxidants and a decrease in the malondialdehyde level of the colon tissue homogenates were observed, suggesting the suppression of lipid peroxidation. Annomuricin E inhibited the growth of HT-29 cells with an IC50 value of 1.62 ± 0.24 μg/ml after 48 h. The cytotoxic effect of annomuricin E was further substantiated by G1 cell cycle arrest and early apoptosis induction in HT-29 cells. Annomuricin E triggered mitochondria-initiated events, including the dissipation of the mitochondrial membrane potential and the leakage of cytochrome c from the mitochondria. Prior to these events, annomuricin E activated caspase 3/7 and caspase 9. Upstream, annomuricin E induced a time-dependent upregulation of Bax and downregulation of Bcl-2 at the mRNA and protein levels. In conclusion, these findings substantiate the usage of A. muricata leaves in ethnomedicine against cancer and highlight annomuricin E as one of the contributing compounds in the

  14. The chemopotential effect of Annona muricata leaves against azoxymethane-induced colonic aberrant crypt foci in rats and the apoptotic effect of Acetogenin Annomuricin E in HT-29 cells: a bioassay-guided approach.

    PubMed

    Zorofchian Moghadamtousi, Soheil; Rouhollahi, Elham; Karimian, Hamed; Fadaeinasab, Mehran; Firoozinia, Mohammad; Ameen Abdulla, Mahmood; Abdul Kadir, Habsah

    2015-01-01

    Annona muricata has been used in folk medicine for the treatment of cancer and tumors. This study evaluated the chemopreventive properties of an ethyl acetate extract of A. muricata leaves (EEAML) on azoxymethane-induced colonic aberrant crypt foci (ACF) in rats. Moreover, the cytotoxic compound of EEAML (Annomuricin E) was isolated, and its apoptosis-inducing effect was investigated against HT-29 colon cancer cell line using a bioassay-guided approach. This experiment was performed on five groups of rats: negative control, cancer control, EEAML (250 mg/kg), EEAML (500 mg/kg) and positive control (5-fluorouracil). Methylene blue staining of colorectal specimens showed that application of EEAML at both doses significantly reduced the colonic ACF formation compared with the cancer control group. Immunohistochemistry analysis showed the down-regulation of PCNA and Bcl-2 proteins and the up-regulation of Bax protein after administration of EEAML compared with the cancer control group. In addition, an increase in the levels of enzymatic antioxidants and a decrease in the malondialdehyde level of the colon tissue homogenates were observed, suggesting the suppression of lipid peroxidation. Annomuricin E inhibited the growth of HT-29 cells with an IC50 value of 1.62 ± 0.24 μg/ml after 48 h. The cytotoxic effect of annomuricin E was further substantiated by G1 cell cycle arrest and early apoptosis induction in HT-29 cells. Annomuricin E triggered mitochondria-initiated events, including the dissipation of the mitochondrial membrane potential and the leakage of cytochrome c from the mitochondria. Prior to these events, annomuricin E activated caspase 3/7 and caspase 9. Upstream, annomuricin E induced a time-dependent upregulation of Bax and downregulation of Bcl-2 at the mRNA and protein levels. In conclusion, these findings substantiate the usage of A. muricata leaves in ethnomedicine against cancer and highlight annomuricin E as one of the contributing compounds in the

  15. Symbiotic Cell Differentiation and Cooperative Growth in Multicellular Aggregates

    PubMed Central

    Yamagishi, Jumpei F; Saito, Nen; Kaneko, Kunihiko

    2016-01-01

    As cells grow and divide under a given environment, they become crowded and resources are limited, as seen in bacterial biofilms and multicellular aggregates. These cells often show strong interactions through exchanging chemicals, as evident in quorum sensing, to achieve mutualism and division of labor. Here, to achieve stable division of labor, three characteristics are required. First, isogenous cells differentiate into several types. Second, this aggregate of distinct cell types shows better growth than that of isolated cells without interaction and differentiation, by achieving division of labor. Third, this cell aggregate is robust with respect to the number distribution of differentiated cell types. Indeed, theoretical studies have thus far considered how such cooperation is achieved when the ability of cell differentiation is presumed. Here, we address how cells acquire the ability of cell differentiation and division of labor simultaneously, which is also connected with the robustness of a cell society. For this purpose, we developed a dynamical-systems model of cells consisting of chemical components with intracellular catalytic reaction dynamics. The reactions convert external nutrients into internal components for cellular growth, and the divided cells interact through chemical diffusion. We found that cells sharing an identical catalytic network spontaneously differentiate via induction from cell-cell interactions, and then achieve division of labor, enabling a higher growth rate than that in the unicellular case. This symbiotic differentiation emerged for a class of reaction networks under the condition of nutrient limitation and strong cell-cell interactions. Then, robustness in the cell type distribution was achieved, while instability of collective growth could emerge even among the cooperative cells when the internal reserves of products were dominant. The present mechanism is simple and general as a natural consequence of interacting cells with

  16. Acute myeloid leukemia cells polarize macrophages towards a leukemia supporting state in a Growth factor independence 1 dependent manner

    PubMed Central

    Al-Matary, Yahya S.; Botezatu, Lacramioara; Opalka, Bertram; Hönes, Judith M.; Lams, Robert F.; Thivakaran, Aniththa; Schütte, Judith; Köster, Renata; Lennartz, Klaus; Schroeder, Thomas; Haas, Rainer; Dührsen, Ulrich; Khandanpour, Cyrus

    2016-01-01

    The growth of malignant cells is not only driven by cell-intrinsic factors, but also by the surrounding stroma. Monocytes/Macrophages play an important role in the onset and progression of solid cancers. However, little is known about their role in the development of acute myeloid leukemia, a malignant disease characterized by an aberrant development of the myeloid compartment of the hematopoietic system. It is also unclear which factors are responsible for changing the status of macrophage polarization, thus supporting the growth of malignant cells instead of inhibiting it. We report herein that acute myeloid leukemia leads to the invasion of acute myeloid leukemia-associated macrophages into the bone marrow and spleen of leukemic patients and mice. In different leukemic mouse models, these macrophages support the in vitro expansion of acute myeloid leukemia cell lines better than macrophages from non-leukemic mice. The grade of macrophage infiltration correlates in vivo with the survival of the mice. We found that the transcriptional repressor Growth factor independence 1 is crucial in the process of macrophage polarization, since its absence impedes macrophage polarization towards a leukemia supporting state and favors an anti-tumor state both in vitro and in vivo. These results not only suggest that acute myeloid leukemia-associated macrophages play an important role in the progression of acute myeloid leukemia, but also implicate Growth factor independence 1 as a pivotal factor in macrophage polarization. These data may provide new insights and opportunities for novel therapies for acute myeloid leukemia. PMID:27390361

  17. Programmed cell death 2 protein induces gastric cancer cell growth arrest at the early S phase of the cell cycle and apoptosis in a p53-dependent manner.

    PubMed

    Zhang, Jian; Wei, Wei; Jin, Hui-Cheng; Ying, Rong-Chao; Zhu, A-Kao; Zhang, Fang-Jie

    2015-01-01

    Programmed cell death 2 (PDCD2) is a highly conserved nuclear protein, and aberrant PDCD2 expression alters cell apoptosis. The present study aimed to investigate PDCD2 expression in gastric cancer. Tissue specimens from 34 gastric cancer patients were collected for analysis of PDCD2 expression using immunohistochemistry, western blotting and qRT-PCR. Gastric cancer cell lines (a p53-mutated MKN28 line and a wild-type p53 MKN45 line) were used to assess the effects of PDCD2 overexpression. p53-/- nude mice were used to investigate the effect of PDCD2 on ultraviolet B (UVB)-induced skin carcinogenesis. The data showed that PDCD2 expression was reduced in gastric cancer tissue specimens, and loss of PDCD2 expression was associated with the poor survival of patients. PDCD2 expression induced gastric cancer cell growth arrest at the early S phase of the cell cycle and apoptosis. The antitumor effects of PDCD2 expression were dependent on p53 expression in gastric cancer cells. Moreover, PDCD2 expression inhibited activity of the ATM/Chk1/2/p53 signaling pathway. In addition, PDCD2 expression suppressed UVB-induced skin carcinogenesis in p53+/+ nude mice, but not in p53-/- mice. The data from the present study demonstrated that loss of PDCD2 expression could contribute to gastric cancer development and progression and that PDCD2-induced gastric cancer cell growth arrest at the early S phase of the cell cycle and apoptosis are p53-dependent. PMID:25334010

  18. Growth hormone deficiency in 'little' mice results in aberrant body composition, reduced insulin-like growth factor-I and insulin-like growth factor-binding protein-3 (IGFBP-3), but does not affect IGFBP-2, -1 or -4.

    PubMed

    Donahue, L R; Beamer, W G

    1993-01-01

    Although GH is known to regulate somatic growth during development, its role in regulating adult body composition is less well defined. The effects of GH on individual body compartments--water, fat, protein and mineral--are achieved both by the action of GH and by a GH-induced hormone, insulin-like growth factor-I (IGF-I). We used a genetic model of GH deficiency, the 'little' (gene symbol lit) mouse, to determine the GH regulation of IGF-I and its insulin-like growth factor-binding proteins (IGFBPs) and to define the interaction between these hormones and each body compartment in adults. Our results showed that GH-deficient lit/lit mice had reduced levels of serum IGF-I (range 38-130 micrograms/l) compared with normal lit/+ littermates (range 432-567 micrograms/l) between 2 and 52 weeks of age. The lit/lit mice did not experience the fivefold increase in IGF-I between 2 and 4 weeks of age that was seen in lit/+ mice. In lit/lit serum, overall binding of 125I-labelled IGF-I to the four IGFBPs was reduced, solely in response to a reduced amount of IGFBP-3. No overall differences were found between lit/lit and lit/+ mice in the binding of 125I-labelled IGF-I to IGFBP-2, -1 or -4. Age-related declines in IGF-I and IGFBPs were seen in lit/lit mice. However, adult levels of IGF-I were maintained in lit/+ mice to at least 52 weeks of age, as were levels of IGFBP-1 and -4, while IGFBP-3 and -2 declined with age. With respect to body composition, comparison of lit/lit with lit/+ mice showed that the lit/lit mice were characterized by abnormally large adipose tissue stores and reduced body water, protein and mineral from 2 weeks onward. These changes occurred despite normal energy intake in lit/lit mice up to 52 weeks of age, indicating that neither undernutrition nor hyperphagia is characteristic of this GH-induced model of obesity. Furthermore, lit/lit males accrued more body fat beginning at an earlier age than lit/lit females. With advancing age, the per cent body fat

  19. Another brick in the cell wall: biosynthesis dependent growth model.

    PubMed

    Barbacci, Adelin; Lahaye, Marc; Magnenet, Vincent

    2013-01-01

    Expansive growth of plant cell is conditioned by the cell wall ability to extend irreversibly. This process is possible if (i) a tensile stress is developed in the cell wall due to the coupling effect between turgor pressure and the modulation of its mechanical properties through enzymatic and physicochemical reactions and if (ii) new cell wall elements can be synthesized and assembled to the existing wall. In other words, expansive growth is the result of coupling effects between mechanical, thermal and chemical energy. To have a better understanding of this process, models must describe the interplay between physical or mechanical variable with biological events. In this paper we propose a general unified and theoretical framework to model growth in function of energy forms and their coupling. This framework is based on irreversible thermodynamics. It is then applied to model growth of the internodal cell of Chara corallina modulated by changes in pressure and temperature. The results describe accurately cell growth in term of length increment but also in term of cell pectate biosynthesis and incorporation to the expanding wall. Moreover, the classical growth model based on Lockhart's equation such as the one proposed by Ortega, appears as a particular and restrictive case of the more general growth equation developed in this paper.

  20. Growth modulating effects of chlorinated oleic acid in cell cultures.

    PubMed

    Høstmark, A T; Lystad, E; Jebens, E; Skramstad, J; Frøyen, P

    1998-07-01

    Chlorinated fatty acids represent a major fraction of extractable, organically bound chlorine in fish. After dietary intake such fatty acids may be transferred from the mother to the foetus through the placenta, and via breast milk to the child. In the present work we have studied the effect of chlorinated oleic acid on the growth of three widely differing types of cells in culture. Chlorinated oleic acid inhibited growth of Human Microvascular Endothelial Cells (HMVEC), Immortilized Human Kidney Epithelial (IHKE) cells, and human Hepatoma cells (HepG2). The order of potency was: HMVEC > IHKE > HepG2. Vitamin E counteracted the inhibitory effect of chlorinated oleic acid on HepG2 cells, but did not significantly affect the fatty acid effect on HMVEC or IHKE. Defatted serum albumin stimulated the growth of HMVEC and IHKE. With HMVEC there was no major interaction between the effect of albumin and chlorinated oleic acid on cell growth. In contrast, with IHKE albumin at low concentration abolished the growth inhibiting effect of chlorinated oleic acid and appreciably counteracted growth inhibition by the fatty acid of HepG2. We conclude that the growth modulation by chlorinated oleic acid and its interaction with vitamin E and albumin are cell specific.

  1. Another brick in the cell wall: biosynthesis dependent growth model.

    PubMed

    Barbacci, Adelin; Lahaye, Marc; Magnenet, Vincent

    2013-01-01

    Expansive growth of plant cell is conditioned by the cell wall ability to extend irreversibly. This process is possible if (i) a tensile stress is developed in the cell wall due to the coupling effect between turgor pressure and the modulation of its mechanical properties through enzymatic and physicochemical reactions and if (ii) new cell wall elements can be synthesized and assembled to the existing wall. In other words, expansive growth is the result of coupling effects between mechanical, thermal and chemical energy. To have a better understanding of this process, models must describe the interplay between physical or mechanical variable with biological events. In this paper we propose a general unified and theoretical framework to model growth in function of energy forms and their coupling. This framework is based on irreversible thermodynamics. It is then applied to model growth of the internodal cell of Chara corallina modulated by changes in pressure and temperature. The results describe accurately cell growth in term of length increment but also in term of cell pectate biosynthesis and incorporation to the expanding wall. Moreover, the classical growth model based on Lockhart's equation such as the one proposed by Ortega, appears as a particular and restrictive case of the more general growth equation developed in this paper. PMID:24066142

  2. Aberration correction of unstable resonators

    NASA Technical Reports Server (NTRS)

    Lang, Robert J. (Inventor)

    1994-01-01

    Construction of aspheric reflectors for unstable resonator lasers to provide an arbitrary laser mode inside the resonator to correct aberrations of an output beam by the construction of the shape of an end reflector opposite the output reflector of the resonator cavity, such as aberrations resulting from refraction of a beam exiting the solid of the resonator having an index of refraction greater than 1 or to produce an aberration in the output beam that will precisely compensate for the aberration of an optical train into which the resonator beam is coupled.

  3. miR-146a inhibits cell growth, cell migration and induces apoptosis in non-small cell lung cancer cells.

    PubMed

    Chen, Gang; Umelo, Ijeoma Adaku; Lv, Shasha; Teugels, Erik; Fostier, Karel; Kronenberger, Peter; Dewaele, Alex; Sadones, Jan; Geers, Caroline; De Grève, Jacques

    2013-01-01

    Aberrant expression of microRNA-146a (miR-146a) has been reported to be involved in the development and progression of various types of cancers. However, its role in non-small cell lung cancer (NSCLC) has not been elucidated. The aim of this study was to investigate the contribution of miR-146a to various aspects of the malignant phenotype of human NSCLCs. In functional experiments, miR-146a suppressed cell growth, induced cellular apoptosis and inhibited EGFR downstream signaling in five NSCLC cell lines (H358, H1650, H1975, HCC827 and H292). miR-146a also inhibited the migratory capacity of these NSCLC cells. On the other hand, miR-146a enhanced the inhibition of cell proliferation by drugs targeting EGFR, including both TKIs (gefitinib, erlotinib, and afatinib) and a monoclonal antibody (cetuximab). These effects were independent of the EGFR mutation status (wild type, sensitizing mutation or resistance mutation), but were less potent compared to the effects of siRNA targeting of EGFR. Our results suggest that these effects of miR-146a are due to its targeting of EGFR and NF-κB signaling. We also found, in clinical formalin fixed paraffin embedded (FFPE) lung cancer samples, that low expression of miR-146a was correlated with advanced clinical TNM stages and distant metastasis in NSCLC (P<0.05). The patients with high miR-146a expression in their tumors showed longer progression-free survival (25.6 weeks in miR-146a high patients vs. 4.8 weeks in miR-146a low patients, P<0.05). miR-146a is therefore a strong candidate prognostic biomarker in NSCLC. Thus inducing miR-146a might be a therapeutic strategy for NSCLC.

  4. Dysregulation of Wnt inhibitory factor 1 (Wif1) expression resulted in aberrant Wnt-β-catenin signaling and cell death of the cloaca endoderm, and anorectal malformations

    PubMed Central

    Ng, R C-L; Matsumaru, D; Ho, A S-H; Garcia-Barceló, M-M; Yuan, Z-W; Smith, D; Kodjabachian, L; Tam, P K-H; Yamada, G; Lui, V C-H

    2014-01-01

    In mammalian urorectal development, the urorectal septum (urs) descends from the ventral body wall to the cloaca membrane (cm) to partition the cloaca into urogenital sinus and rectum. Defective urs growth results in human congenital anorectal malformations (ARMs), and their pathogenic mechanisms are unclear. Recent studies only focused on the importance of urs mesenchyme proliferation, which is induced by endoderm-derived Sonic Hedgehog (Shh). Here, we showed that the programmed cell death of the apical urs and proximal cm endoderm is particularly crucial for the growth of urs during septation. The apoptotic endoderm was closely associated with the tempo-spatial expression of Wnt inhibitory factor 1 (Wif1), which is an inhibitor of Wnt-β-catenin signaling. In Wif1lacZ/lacZ mutant mice and cultured urorectum with exogenous Wif1, cloaca septation was defective with undescended urs and hypospadias-like phenotypes, and such septation defects were also observed in Shh−/− mutants and in endodermal β-catenin gain-of-function (GOF) mutants. In addition, Wif1 and Shh were expressed in a complementary manner in the cloaca endoderm, and Wif1 was ectopically expressed in the urs and cm associated with excessive endodermal apoptosis and septation defects in Shh−/− mutants. Furthermore, apoptotic cells were markedly reduced in the endodermal β-catenin GOF mutant embryos, which counteracted the inhibitory effects of Wif1. Taken altogether, these data suggest that regulated expression of Wif1 is critical for the growth of the urs during cloaca septation. Hence, Wif1 governs cell apoptosis of urs endoderm by repressing β-catenin signal, which may facilitate the protrusion of the underlying proliferating mesenchymal cells towards the cm for cloaca septation. Dysregulation of this endodermal Shh-Wif1-β-catenin signaling axis contributes to ARM pathogenesis. PMID:24632949

  5. Overexpression of caspase 7 is ERα dependent to affect proliferation and cell growth in breast cancer cells by targeting p21Cip

    PubMed Central

    Chaudhary, S; Madhukrishna, B; Adhya, A K; Keshari, S; Mishra, S K

    2016-01-01

    Caspase 7 (CASP7) expression has important function during cell cycle progression and cell growth in certain cancer cells and is also involved in the development and differentiation of dental tissues. However, the function of CASP7 in breast cancer cells is unclear. The aim of this study was to analyze the expression of CASP7 in breast carcinoma patients and determine the role of CASP7 in regulating tumorigenicity in breast cancer cells. In this study, we show that the CASP7 expression is high in breast carcinoma tissues compared with normal counterpart. The ectopic expression of CASP7 is significantly associated with ERα expression status and persistently elevated in different stages of the breast tumor grades. High level of CASP7 expression showed better prognosis in breast cancer patients with systemic endocrine therapy as observed from Kaplan–Meier analysis. S3 and S4, estrogen responsive element (ERE) in the CASP7 promoter, is important for estrogen-ERα-mediated CASP7 overexpression. Increased recruitment of p300, acetylated H3 and pol II in the ERE region of CASP7 promoter is observed after hormone stimulation. Ectopic expression of CASP7 in breast cancer cells results in cell growth and proliferation inhibition via p21Cip reduction, whereas small interfering RNA (siRNA) mediated reduction of CASP7 rescued p21Cip levels. We also show that pro- and active forms of CASP7 is located in the nucleus apart from cytoplasmic region of breast cancer cells. The proliferation and growth of breast cancer cells is significantly reduced by broad-spectrum peptide inhibitors and siRNA of CASP7. Taken together, our findings show that CASP7 is aberrantly expressed in breast cancer and contributes to cell growth and proliferation by downregulating p21Cip protein, suggesting that targeting CASP7-positive breast cancer could be one of the potential therapeutic strategies. PMID:27089142

  6. Overexpression of caspase 7 is ERα dependent to affect proliferation and cell growth in breast cancer cells by targeting p21(Cip).

    PubMed

    Chaudhary, S; Madhukrishna, B; Adhya, A K; Keshari, S; Mishra, S K

    2016-04-18

    Caspase 7 (CASP7) expression has important function during cell cycle progression and cell growth in certain cancer cells and is also involved in the development and differentiation of dental tissues. However, the function of CASP7 in breast cancer cells is unclear. The aim of this study was to analyze the expression of CASP7 in breast carcinoma patients and determine the role of CASP7 in regulating tumorigenicity in breast cancer cells. In this study, we show that the CASP7 expression is high in breast carcinoma tissues compared with normal counterpart. The ectopic expression of CASP7 is significantly associated with ERα expression status and persistently elevated in different stages of the breast tumor grades. High level of CASP7 expression showed better prognosis in breast cancer patients with systemic endocrine therapy as observed from Kaplan-Meier analysis. S3 and S4, estrogen responsive element (ERE) in the CASP7 promoter, is important for estrogen-ERα-mediated CASP7 overexpression. Increased recruitment of p300, acetylated H3 and pol II in the ERE region of CASP7 promoter is observed after hormone stimulation. Ectopic expression of CASP7 in breast cancer cells results in cell growth and proliferation inhibition via p21(Cip) reduction, whereas small interfering RNA (siRNA) mediated reduction of CASP7 rescued p21(Cip) levels. We also show that pro- and active forms of CASP7 is located in the nucleus apart from cytoplasmic region of breast cancer cells. The proliferation and growth of breast cancer cells is significantly reduced by broad-spectrum peptide inhibitors and siRNA of CASP7. Taken together, our findings show that CASP7 is aberrantly expressed in breast cancer and contributes to cell growth and proliferation by downregulating p21(Cip) protein, suggesting that targeting CASP7-positive breast cancer could be one of the potential therapeutic strategies.

  7. Aberrant Wnt/β-catenin signaling and elevated expression of stem cell proteins are associated with osteosarcoma side population cells of high tumorigenicity.

    PubMed

    Yi, Xi-Jun; Zhao, Yu-Hua; Qiao, Li-Xiang; Jin, Chun-Lei; Tian, Jing; Li, Qiu-Shi

    2015-10-01

    According to the cancer stem cell theory, the presence of a small sub‑population of cancer cells, termed cancer stem cells (CSCs), have a significant implication on cancer treatment and are responsible for tumor recurrence. Previous studies have reported that alterations in the Wnt/β‑catenin signaling are crucial in the maintenance of CSCs. In the present study, the characteristic features and activation of Wnt/β‑catenin signaling in CSCs from osteosarcoma, an aggressive human bone tumor, were investigated. In total, ~2.1% of the cancer stem‑like side population (SP) cells were identified in the osteosarcoma samples. The results of subsequent western blot and reverse transcription‑quantitative polymerase chain reaction analyses revealed that the protein levels of β‑catenin and cyclin D1 were markedly upregulated in the fluorescence‑activated cell sorted osteosarcoma SP cells. In addition, the elevated expression levels of stem cell proteins, including CD133, nestin Oct‑4, Sox‑2 and Nanog were significantly higher in the SP cells, which contributed to self‑renewal and enhanced the proliferation rate of the SP cells. Furthermore, the SP cells were found to be highly invasive and able to form tumors in vivo. Taken together, these data suggested that the identification of novel anticancer drugs, which suppress the Wnt/β‑catenin signaling and its downstream pathway may assist in eradicating osteosarcoma stem cells.

  8. Dynamic mast cell-stromal cell interactions promote growth of pancreatic cancer

    PubMed Central

    Ma, Ying; Hwang, Rosa F.; Logsdon, Craig D.; Ullrich, Stephen E.

    2013-01-01

    Pancreatic ductal adenocarcinoma (PDAC) exists in a complex desmoplastic microenvironment, which includes cancer-associated fibroblasts (also known as pancreatic stellate cells, PSCs) and immune cells that provide a fibrotic niche that impedes successful cancer therapy. We have found that mast cells are essential for PDAC tumorigenesis. Whether mast cells contribute to the growth of PDAC and/or PSCs is unknown. Here we tested the hypothesis that mast cells contribute to the growth of PSCs and tumor cells, thus contributing to PDAC development. Tumor cells promoted mast cell migration. Both tumor cells and PSCs stimulated mast cell activation. Conversely, mast cell-derived IL-13 and tryptase stimulated PSC proliferation. Treating tumor-bearing mice with agents that block mast cell migration and function depressed PDAC growth. Our findings suggest that mast cells exacerbate the cellular and extracellular dynamics of the tumor microenvironment found in PDAC. Therefore, targeting mast cells may inhibit stromal formation and improve therapy. PMID:23633481

  9. Aberrant cell cycle progression contributes to the early-stage accelerated carcinogenesis in transgenic epidermis expressing the dominant negative TGFbetaRII.

    PubMed

    Go, C; He, W; Zhong, L; Li, P; Huang, J; Brinkley, B R; Wang, X J

    2000-07-27

    Mutations in the transforming growth factor beta type II receptor (TGFbetaRII) have been found in various malignant tumors, suggesting that loss of TGFbeta signaling plays a causal role in late-stage cancer development. To test whether loss of TGFbetaRII is involved in early-stage carcinogenesis, we have generated transgenic mice expressing a dominant negative TGFbetaRII (deltabetaRII) in the epidermis. These mice exhibited an increased susceptibility to chemical carcinogenesis protocols at both early and late stages. In the current study, parameters for cell cycle progression and chromosome instability were analysed in deltabetaRII tumors. DeltabetaRII papillomas showed an increased S phase in flow cytometry. Bromodeoxyuridine (BrdU) labeling and mitotic indices in deltabetaRII papillomas also showed a threefold increase compared to papillomas developing in non-transgenic mice. When papillomas further progressed to squamous cell carcinomas (SCC), both control and deltabetaRII SCC showed similar BrdU labeling indices and percentages of S phase cells. However, deltabetaRII SCC cells showed a sixfold increase in the G2/M population. Mitotic indices in deltabetaRII SCC also showed a threefold increase compared to non-transgenic SCC. Consistent with a perturbed cell cycle, deltabetaRII papillomas and SCC showed reduced expression of the TGFbeta target genes p15 (INK4b), p21 (WAF-1) and p27 (Kip1), inhibitors of cyclin-dependent kinases (cdks). However, most deltabetaRII papilloma cells exhibited normal centrosome numbers, and deltabetaRII SCC exhibited a similar extent of centrosome abnormalities compared to control SCC (35-40% cells). Most of deltabetaRII SCC exhibited diploid chromosome profiles. These data indicate that inactivation of TGFbetaRII accelerates skin tumorigenesis at early stages by the acceleration of loss of cell cycle control, but not by increased chromosome instability.

  10. The Histone Deacetylase Inhibitor Vaproic Acid Induces Cell Growth Arrest in Hepatocellular Carcinoma Cells via Suppressing Notch Signaling

    PubMed Central

    Sun, Guangchun; Mackey, Lily V.; Coy, David H.; Yu, Cui-Yun; Sun, Lichun

    2015-01-01

    Hepatocellular carcinoma (HCC) is a type of malignant cancer. Notch signaling is aberrantly expressed in HCC tissues with more evidence showing that this signaling plays a critical role in HCCs. In the present study, we investigate the effects of the anti-convulsant drug valproic acid (VPA) in HCC cells and its involvement in modulating Notch signaling. We found that VPA, acting as a histone deacetylase (HDAC) inhibitor, induced a decrease in HDAC4 and an increase in acetylated histone 4 (AcH4) and suppressed HCC cell growth. VPA also induced down-regulation of Notch signaling via suppressing the expression of Notch1 and its target gene HES1, with an increase of tumor suppressor p21 and p63. Furthermore, Notch1 activation via overexpressing Notch1 active form ICN1 induced HCC cell proliferation and anti-apoptosis, indicating Notch signaling played an oncogenic role in HCC cells. Meanwhile, VPA could reverse Notch1-induced increase of cell proliferation. Interestingly, VPA was also observed to stimulate the expression of G protein-coupled somatostatin receptor type 2 (SSTR2) that has been used in receptor-targeting therapies. This discovery supports a combination therapy of VPA with the SSTR2-targeting agents. Our in vitro assay did show that the combination of VPA and the peptide-drug conjugate camptothecin-somatostatin (CPT-SST) displayed more potent anti-proliferative effects on HCC cells than did each alone. VPA may be a potential drug candidate in the development of anti-HCC drugs via targeting Notch signaling, especially in combination with receptor-targeting cytotoxic agents. PMID:26366213

  11. Physcomitrella patens: a model for tip cell growth and differentiation.

    PubMed

    Vidali, Luis; Bezanilla, Magdalena

    2012-12-01

    The moss Physcomitrella patens has emerged as an excellent model system owing to its amenability to reverse genetics. The moss gametophyte has three filamentous tissues that grow by tip growth: chloronemata, caulonemata, and rhizoids. Because establishment of the moss plant relies on this form of growth, it is particularly suited for dissecting the molecular basis of tip growth. Recent studies demonstrate that a core set of actin cytoskeletal proteins is essential for tip growth. Additional actin cytoskeletal components are required for modulating growth to produce caulonemata and rhizoids. Differentiation into these cell types has previously been linked to auxin, light and nutrients. Recent studies have identified that core auxin signaling components as well as transcription factors that respond to auxin or nutrient levels are required for tip-growing cell differentiation. Future studies may establish a connection between the actin cytoskeleton and auxin or nutrient-induced cell differentiation.

  12. Targeting Btk with ibrutinib inhibit gastric carcinoma cells growth

    PubMed Central

    Wang, Jin Dao; Chen, Xiao Ying; Ji, Ke Wei; Tao, Feng

    2016-01-01

    Bruton’s tyrosine kinase (Btk) is a member of the Tec-family non-receptor tyrosine kinases family. It has previously been reported to be expressed in B cells and has an important role in B-cell malignancies. While the roles of Btk in the pathogenesis of certain B-cell malignancies are well established, the functions of Btk in gastric carcinoma have never been investigated. Herein, we found that Btk is over-expressed in gastric carcinoma tissues and gastric cancer cells. Knockdown of Btk expression selectively inhibits the growth of gastric cancer cells, but not that of the normal gastric mucosa epithelial cell, which express very little Btk. Inhibition of Btk by its inhibitor ibrutinib has an additive inhibitory effect on gastric cancer cell growth. Treatment of gastric cancer cells, but not immortalized breast epithelial cells with ibrutinib results in effective cell killing, accompanied by the attenuation of Btk signals. Ibrutinib also induces apoptosis in gastric carcinoma cells as well as is a chemo-sensitizer for docetaxel (DTX), a standard of care for gastric carcinoma patients. Finally, ibrutinib markedly reduces tumor growth and increases tumor cell apoptosis in the tumors formed in mice inoculated with the gastric carcinoma cells. Given these promising preclinical results for ibrutinib in gastric carcinoma, a strategy combining Btk inhibitor warrants attention in gastric cancer. PMID:27508020

  13. Catalase regulates cell growth in HL60 human promyelocytic cells: evidence for growth regulation by H(2)O(2).

    PubMed

    Hachiya, Misao; Akashi, Makoto

    2005-03-01

    Reactive oxygen species (ROS) including hydrogen peroxide (H(2)O(2)) are generated constitutively in mammalian cells. Because of its relatively long life and high permeability across membranes, H(2)O(2) is thought to be an important second messenger. Generation of H(2)O(2) is increased in response to external insults, including radiation. Catalase is located at the peroxisome and scavenges H(2)O(2). In this study, we investigated the role of catalase in cell growth using the H(2)O(2)-resistant variant HP100-1 of human promyelocytic HL60 cells. HP100-1 cells had an almost 10-fold higher activity of catalase than HL60 cells without differences in levels of glutathione peroxidase, manganese superoxide dismutase (MnSOD), and copper-zinc SOD (CuZnSOD). HP100-1 cells had higher proliferative activity than HL60 cells. Treatment with catalase or the introduction of catalase cDNA into HL60 cells stimulated cell growth. Exposure of HP100-1 cells to a catalase inhibitor resulted in suppression of cell growth with concomitant increased levels of intracellular H(2)O(2). Moreover, exogenously added H(2)O(2) or depletion of glutathione suppressed cell growth in HL60 cells. Extracellular signal regulated kinase 1/2 (ERK1/2) was constitutively phosphorylated in HP100-1 cells but not in HL60 cells. Inhibition of the ERK1/2 pathway suppressed the growth of HP100-1 cells, but inhibition of p38 mitogen-activated protein kinase (p38MAPK) did not affect growth. Moreover, inhibition of catalase blocked the phosphorylation of ERK1/2 but not of p38MAPK in HP100-1 cells. Thus our results suggest that catalase activates the growth of HL60 cells through dismutation of H(2)O(2), leading to activation of the ERK1/2 pathway; H(2)O(2) is an important regulator of growth in HL60 cells.

  14. Purification and cultivation of human pituitary growth hormone secreting cells

    NASA Technical Reports Server (NTRS)

    Hymer, W. C.

    1984-01-01

    A multiphase study was conducted to examine the properties of growth hormone cells. Topics investigated included: (1) to determine if growth hormone (GH) cells contained within the rat pituitary gland can be separated from the other hormone producing cell types by continuous flow electrophoresis (CFE); (2) to determine what role, if any, gravity plays in the electrophoretic separation of GH cells; (3) to compare in vitro GH release from rat pituitary cells previously exposed to microgravity conditions vs release from cells not exposed to microgravity; (4) to determine if the frequency of different hormone producing pituitary cell types contained in cell suspensions can be quantitated by flow cytometry; and (5) to determine if GH contained within the human post mortem pituitary gland can be purified by CFE. Specific experimental procedures and results are included.

  15. The Croonian Lecture 1997. The phosphorylation of proteins on tyrosine: its role in cell growth and disease.

    PubMed Central

    Hunter, T

    1998-01-01

    The reversible phosphorylation of tyrosines in proteins plays a key role in regulating many different processes in eukaryotic organisms, such as growth control, cell cycle control, differentiation cell shape and movement, gene transcription, synaptic transmission, and insulin action. Phosphorylation of proteins is brought about by enzymes called protein-tyrosine kinases that add phosphate to specific tyrosines in target proteins; phosphate is removed from phosphorylated tyrosines by enzymes called protein-tyrosine phosphatases. Phosphorylated tyrosines are recognized by specialized binding domains on other proteins, and such interactions are used to initiate intracellular signaling pathways. Currently, more than 95 protein-tyrosine kinases and more than 55 protein-tyrosine phosphatase genes are known in Homo sapiens. Aberrant tyrosine phosphorylation is a hallmark of many types of cancer and other human diseases. Drugs are being developed that antagonize the responsible protein-tyrosine kinases and phosphatases in order to combat these diseases. PMID:9602534

  16. The impact of homologous recombination repair deficiency on depleted uranium clastogenicity in Chinese hamster ovary cells: XRCC3 protects cells from chromosome aberrations, but increases chromosome fragmentation.

    PubMed

    Holmes, Amie L; Joyce, Kellie; Xie, Hong; Falank, Carolyne; Hinz, John M; Wise, John Pierce

    2014-04-01

    Depleted uranium (DU) is extensively used in both industry and military applications. The potential for civilian and military personnel exposure to DU is rising, but there are limited data on the potential health hazards of DU exposure. Previous laboratory research indicates DU is a potential carcinogen, but epidemiological studies remain inconclusive. DU is genotoxic, inducing DNA double strand breaks, chromosome damage and mutations, but the mechanisms of genotoxicity or repair pathways involved in protecting cells against DU-induced damage remain unknown. The purpose of this study was to investigate the effects of homologous recombination repair deficiency on DU-induced genotoxicity using RAD51D and XRCC3-deficient Chinese hamster ovary (CHO) cell lines. Cells deficient in XRCC3 (irs1SF) exhibited similar cytotoxicity after DU exposure compared to wild-type (AA8) and XRCC3-complemented (1SFwt8) cells, but DU induced more break-type and fusion-type lesions in XRCC3-deficient cells compared to wild-type and XRCC3-complemented cells. Surprisingly, loss of RAD51D did not affect DU-induced cytotoxicity or genotoxicity. DU induced selective X-chromosome fragmentation irrespective of RAD51D status, but loss of XRCC3 nearly eliminated fragmentation observed after DU exposure in wild-type and XRCC3-complemented cells. Thus, XRCC3, but not RAD51D, protects cells from DU-induced breaks and fusions and also plays a role in DU-induced chromosome fragmentation. PMID:24561002

  17. Purification and cultivation of human pituitary growth hormone secreting cells

    NASA Technical Reports Server (NTRS)

    Hymer, W. C.

    1978-01-01

    The maintainance of actively secreting human pituitary growth hormone cells (somatotrophs) in vitro was studied. The primary approach was the testing of agents which may be expected to increase the release of the human growth hormone (hGH). A procedure for tissue procurement is described along with the methodologies used to dissociate human pituitary tissue (obtained either at autopsy or surgery) into single cell suspensions. The validity of the Biogel cell column perfusion system for studying the dynamics of GH release was developed and documented using a rat pituitary cell system.

  18. TOR and paradigm change: cell growth is controlled.

    PubMed

    Hall, Michael N

    2016-09-15

    This year marks the 25th anniversary of the discovery of target of rapamycin (TOR), a highly conserved kinase and central controller of cell growth. In this Retrospective, I briefly describe the discovery of TOR and the subsequent elucidation of its cellular role. I place particular emphasis on an article by Barbet et al. from 1996, the first suggesting that TOR controls cell growth in response to nutrients. PMID:27634743

  19. TOR and paradigm change: cell growth is controlled.

    PubMed

    Hall, Michael N

    2016-09-15

    This year marks the 25th anniversary of the discovery of target of rapamycin (TOR), a highly conserved kinase and central controller of cell growth. In this Retrospective, I briefly describe the discovery of TOR and the subsequent elucidation of its cellular role. I place particular emphasis on an article by Barbet et al. from 1996, the first suggesting that TOR controls cell growth in response to nutrients.

  20. Cell growth on immobilized cell growth factor. 7. Protein-free cell culture by using growth-factor-immobilized polymer membrane.

    PubMed

    Liu, S Q; Ito, Y; Imanishi, Y

    1993-02-01

    A protein-free culture of anchorage-dependent cells, mouse fibroblast cells, STO and 3T3-L1 and fibroic sarcoma cells, Swiss albino HSDM1C1, grown on a cell-growth protein, insulin, and/or a cell-adhesion protein, collagen, which are immobilized or coimmobilized on surface-hydrolyzed poly(methyl methacrylate) membrane, was investigated. By adding metal ions and lipids to the culture medium, a protein-free culture medium was composed, which was potent in promoting cell proliferation similarly to serum-containing culture medium. In particular, with insulin/collagen-coimmobilized membrane, a protein-free culture was established without detachment of growing cells over a long period. These protein-immobilized membranes could be used repeatedly. PMID:7763456

  1. Aberrant CD8+ T-Cell Responses and Memory Differentiation upon Viral Infection of an Ataxia-Telangiectasia Mouse Model Driven by Hyper-Activated Akt and mTORC1 Signaling

    PubMed Central

    D'Souza, Anthony D.; Parish, Ian A.; McKay, Sharen E.; Kaech, Susan M.; Shadel, Gerald S.

    2011-01-01

    Immune system-related pathology is common in ataxia-telangiectasia (A-T) patients and mice that lack the protein kinase, A-T mutated (ATM). However, it has not been studied how ATM influences immune responses to a viral infection. Using the lymphocytic choriomeningitis virus (LCMV) infection model, we show that ATM−/− mice, despite having fewer naïve CD8+ T cells, effectively clear the virus. However, aberrant CD8+ T-cell responses are observed, including defective expansion and contraction, effector-to-memory differentiation, and a switch in viral-epitope immunodominance. T-cell receptor-activated, but not naïve, ATM−/− splenic CD8+ T cells have increased ribosomal protein S6 and Akt phosphorylation and do not proliferate well in response to IL-15, a cytokine important for memory T-cell development. Accordingly, pharmacological Akt or mammalian target of rapamycin complex 1 (mTORC1) inhibition during T-cell receptor activation alone rescues the IL-15 proliferation defect. Finally, rapamycin treatment during LCMV infection in vivo increases the number of memory T cells in ATM−/− mice. Altogether, these results show that CD8+ T cells lacking ATM have hyperactive Akt and mTORC1 signaling in response to T-cell receptor activation, which results in aberrant cytokine responses and memory T-cell development. We speculate that similar signaling defects contribute to the immune system pathology of A-T, and that inhibition of Akt and/or mTORC1 may be of therapeutic value. PMID:21641396

  2. Simultaneous knockdown of BRAF and expression of INK4A in melanoma cells leads to potent growth inhibition and apoptosis

    SciTech Connect

    Zhao Yanhua; Zhang Yan; Yang Zhen; Li, Albert; Dong Jianli

    2008-06-06

    Abnormal BRAF and p16INK4A co-exist in 60% of melanomas. BRAF mutation also occurs in 80% of benign nevi where it turns-on p16INK4A resulting in proliferative senescence; loss of p16INK4A removes the inhibitory block leading to melanoma development. Since only melanomas with wild-type BRAF have amplified CDK4 and cyclin D1 genes, p16INK4A-CDK4/6-cyclin D pathway is viewed as linearly downstream of BRAF. Thus, co-occurrence of aberrant BRAF and INK4A may be remnant of changes during melanoma formation without functional significance. To explore this notion, we simultaneously knocked down BRAF (via siRNA) and expressed INK4A cDNA in melanoma cells and observed enhanced growth inhibition. Notably, although each alone had no statistically significant effect on apoptosis, co-expression of BRAF siRNA and INK4A cDNA caused potent apoptosis, which was associated with up-regulation of BIM and down-regulation of BCL2. Our results suggest that aberrant BRAF and INK4A cooperate to promote proliferation and survival of melanoma cells.

  3. Camera processing with chromatic aberration.

    PubMed

    Korneliussen, Jan Tore; Hirakawa, Keigo

    2014-10-01

    Since the refractive index of materials commonly used for lens depends on the wavelengths of light, practical camera optics fail to converge light to a single point on an image plane. Known as chromatic aberration, this phenomenon distorts image details by introducing magnification error, defocus blur, and color fringes. Though achromatic and apochromatic lens designs reduce chromatic aberration to a degree, they are complex and expensive and they do not offer a perfect correction. In this paper, we propose a new postcapture processing scheme designed to overcome these problems computationally. Specifically, the proposed solution is comprised of chromatic aberration-tolerant demosaicking algorithm and post-demosaicking chromatic aberration correction. Experiments with simulated and real sensor data verify that the chromatic aberration is effectively corrected. PMID:25163060

  4. Chromosome aberrations induced in human lymphocytes by U-235 fission neutrons: I. Irradiation of human blood samples in the "dry cell" of the TRIGA Mark II nuclear reactor.

    PubMed

    Fajgelj, A; Lakoski, A; Horvat, D; Remec, I; Skrk, J; Stegnar, P

    1991-11-01

    A set-up for irradiation of biological samples in the TRIGA Mark II research reactor in Ljubljana is described. Threshold activation detectors were used for characterisation of the neutron flux, and the accompanying gamma dose was measured by TLDs. Human peripheral blood samples were irradiated "in vitro" and biological effects evaluated according to the unstable chromosomal aberrations induced. Biological effects of two types of cultivation of irradiated blood samples, the first immediately after irradiation and the second after 96 h storage, were studied. A significant difference in the incidence of chromosomal aberrations between these two types of samples was obtained, while our dose-response curve fitting coefficients alpha 1 = (7.71 +/- 0.09) x 10(-2) Gy-1 (immediate cultivation) and alpha 2 = (11.03 +/- 0.08) x 10(-2) Gy-1 (96 h delayed cultivation) are in both cases lower than could be found in the literature.

  5. Chromosome aberrations induced in human lymphocytes by U-235 fission neutrons: I. Irradiation of human blood samples in the "dry cell" of the TRIGA Mark II nuclear reactor.

    PubMed

    Fajgelj, A; Lakoski, A; Horvat, D; Remec, I; Skrk, J; Stegnar, P

    1991-11-01

    A set-up for irradiation of biological samples in the TRIGA Mark II research reactor in Ljubljana is described. Threshold activation detectors were used for characterisation of the neutron flux, and the accompanying gamma dose was measured by TLDs. Human peripheral blood samples were irradiated "in vitro" and biological effects evaluated according to the unstable chromosomal aberrations induced. Biological effects of two types of cultivation of irradiated blood samples, the first immediately after irradiation and the second after 96 h storage, were studied. A significant difference in the incidence of chromosomal aberrations between these two types of samples was obtained, while our dose-response curve fitting coefficients alpha 1 = (7.71 +/- 0.09) x 10(-2) Gy-1 (immediate cultivation) and alpha 2 = (11.03 +/- 0.08) x 10(-2) Gy-1 (96 h delayed cultivation) are in both cases lower than could be found in the literature. PMID:1962281

  6. CD229 is expressed on the surface of plasma cells carrying an aberrant phenotype and chemotherapy-resistant precursor cells in multiple myeloma

    PubMed Central

    Yousef, Sara; Kovacsovics-Bankowski, Magdalena; Salama, Mohamed E; Bhardwaj, Neelam; Steinbach, Mary; Langemo, Amanda; Kovacsovics, Tibor; Marvin, James; Binder, Mascha; Panse, Jens; Kröger, Nicolaus; Luetkens, Tim; Atanackovic, Djordje

    2015-01-01

    Multiple Myeloma (MM) is a plasma cell (PC) malignancy, which despite significant therapeutic advances, is still considered incurable. This is due to the persistence of chemotherapy-resistant minimal residual disease in the patients' bone marrow (BM) after an effective induction therapy. Immunotherapies targeting surface molecules expressed on the bulk of tumor cells and the chemotherapy-resistant, myeloma-propagating cells could play a central role in this clinical setting. We recently described surface molecule CD229 as a potential therapeutic target for MM. In our current study we assessed the expression of CD229 on different PC subtypes and on cells with a myeloma-propagating phenotype in a total of 77 patients with PC dyscrasias independently at 2 different cancer centers. We found that CD229 was strongly and homogeneously overexpressed on the PC of patients with monoclonal gammopathy of undetermined significance (MGUS), smoldering myeloma, MM, and PC leukemia. CD229 was particularly overexpressed on those PC showing an abnormal phenotype such as expression of CD56. Most importantly, CD229 was also highly expressed on those cells in the patients' BM displaying the phenotype of chemotherapy-resistant and myeloma-propagating cells. In conclusion, our combined findings suggest that immunotherapies targeting CD229 will not only be effective for the bulk of tumor cells but will also help to eradicate chemotherapy-resistant cells remaining in the patients' BM after induction treatment. Hopefully, the design of CD229-specific monoclonal antibodies or chimeric antigen receptor-transduced T cells will help to achieve prolonged remissions or even cures in MM patients. PMID:26001047

  7. Epitaxial silicon growth for solar cells

    NASA Technical Reports Server (NTRS)

    Daiello, R. V.; Robinson, P. H.; Richman, D.

    1979-01-01

    The epitaxial procedures, solar cell fabrication, and evaluation techniques are described. The development of baseline epitaxial solar cell structures grown on high quality conventional silicon substrates is discussed. Diagnostic layers and solar cells grown on four potentially low cost silicon substrates are considered. The crystallographic properties of such layers and the performance of epitaxially grown solar cells fabricated on these materials are described. An advanced epitaxial reactor, the rotary disc, is described along with the results of growing solar cell structures of the baseline type on low cost substrates. The add on cost for the epitaxial process is assessed and the economic advantages of the epitaxial process as they relate to silicon substrate selection are examined.

  8. Critical telomerase activity for uncontrolled cell growth

    NASA Astrophysics Data System (ADS)

    Wesch, Neil L.; Burlock, Laura J.; Gooding, Robert J.

    2016-08-01

    The lengths of the telomere regions of chromosomes in a population of cells are modelled using a chemical master equation formalism, from which the evolution of the average number of cells of each telomere length is extracted. In particular, the role of the telomere-elongating enzyme telomerase on these dynamics is investigated. We show that for biologically relevant rates of cell birth and death, one finds a critical rate, R crit, of telomerase activity such that the total number of cells diverges. Further, R crit is similar in magnitude to the rates of mitosis and cell death. The possible relationship of this result to replicative immortality and its associated hallmark of cancer is discussed.

  9. Critical telomerase activity for uncontrolled cell growth.

    PubMed

    Wesch, Neil L; Burlock, Laura J; Gooding, Robert J

    2016-01-01

    The lengths of the telomere regions of chromosomes in a population of cells are modelled using a chemical master equation formalism, from which the evolution of the average number of cells of each telomere length is extracted. In particular, the role of the telomere-elongating enzyme telomerase on these dynamics is investigated. We show that for biologically relevant rates of cell birth and death, one finds a critical rate, R crit, of telomerase activity such that the total number of cells diverges. Further, R crit is similar in magnitude to the rates of mitosis and cell death. The possible relationship of this result to replicative immortality and its associated hallmark of cancer is discussed. PMID:27500377

  10. Tumor vascular permeability factor stimulates endothelial cell growth and angiogenesis.

    PubMed Central

    Connolly, D T; Heuvelman, D M; Nelson, R; Olander, J V; Eppley, B L; Delfino, J J; Siegel, N R; Leimgruber, R M; Feder, J

    1989-01-01

    Vascular permeability factor (VPF) is an Mr 40-kD protein that has been purified from the conditioned medium of guinea pig line 10 tumor cells grown in vitro, and increases fluid permeability from blood vessels when injected intradermally. Addition of VPF to cultures of vascular endothelial cells in vitro unexpectedly stimulated cellular proliferation. VPF promoted the growth of new blood vessels when administered into healing rabbit bone grafts or rat corneas. The identity of the growth factor activity with VPF was established in four ways: (a) the molecular weight of the activity in preparative SDS-PAGE was the same as VPF (Mr approximately 40 kD); (b) multiple isoforms (pI greater than or equal to 8) for both VPF and the growth-promoting activity were observed; (c) a single, unique NH2-terminal amino acid sequence was obtained; (d) both growth factor and permeability-enhancing activities were immunoadsorbed using antipeptide IgG that recognized the amino terminus of VPF. Furthermore, 125I-VPF was shown to bind specifically and with high affinity to endothelial cells in vitro and could be chemically cross-linked to a high-molecular weight cell surface receptor, thus demonstrating a mechanism whereby VPF can interact directly with endothelial cells. Unlike other endothelial cell growth factors, VPF did not stimulate [3H]thymidine incorporation or promote growth of other cell types including mouse 3T3 fibroblasts or bovine smooth muscle cells. VPF, therefore, appears to be unique in its ability to specifically promote increased vascular permeability, endothelial cell growth, and angio-genesis. Images PMID:2478587

  11. MicroRNA-338-3p suppresses tumor growth of esophageal squamous cell carcinoma in vitro and in vivo.

    PubMed

    Li, Xinyu; Li, Zhihong; Yang, Guiyun; Pan, Zhenxiang

    2015-09-01

    Accumulating evidence has shown that microRNAs (miRNAs) are aberrantly expressed in human esophageal squamous cell carcinoma (ESCC) and are crucial in tumorigenesis, among which miR‑338‑3p has been examined to be downregulated in patients with ESCC. However, the role of miR‑338‑3p in ESCC remains to be elucidated. In the present study, the role of miR‑338‑3p on the growth and survival of an ESCC cell line was determined with several in vitro approaches and in nude mouse models. It was determined that miR‑338‑3p expression was frequently downregulated in ESCC tissue compared with corresponding adjacent non‑tumor tissue, and that its expression was significantly correlated with tumor stage and metastasis. Overexpression of miR‑338‑3p in ESCC cells suppressed cell proliferation, colony formation, migration and invasion, and induced cell arrest at the G0/G1 stage and cell apoptosis in vitro. In addition, it was demonstrated that overexpression of miR‑338‑3p significantly suppresses tumor growth of xenograft tumors in mice (P<0.05). These findings revealed that miR‑338‑3p may act as a tumor suppressor in ESCC, and its dysregulation may be involved in the initiation and development of human ESCC. In addition, it was suggested that miR‑338‑3p may be a potential therapeutic agent for treatment of ESCC.

  12. Human Wharton’s Jelly Mesenchymal Stem Cells Plasticity Augments Scar-Free Skin Wound Healing with Hair Growth

    PubMed Central

    Sabapathy, Vikram; Sundaram, Balasubramanian; VM, Sreelakshmi; Mankuzhy, Pratheesh; Kumar, Sanjay

    2014-01-01

    Human mesenchymal stem cells (MSCs) are a promising candidate for cell-based transplantation and regenerative medicine therapies. Thus in the present study Wharton’s Jelly Mesenchymal Stem Cells (WJ-MSCs) have been derived from extra embryonic umbilical cord matrix following removal of both arteries and vein. Also, to overcome the clinical limitations posed by fetal bovine serum (FBS) supplementation because of xenogeneic origin of FBS, usual FBS cell culture supplement has been replaced with human platelet lysate (HPL). Apart from general characteristic features of bone marrow-derived MSCs, wharton jelly-derived MSCs have the ability to maintain phenotypic attributes, cell growth kinetics, cell cycle pattern, in vitro multilineage differentiation plasticity, apoptotic pattern, normal karyotype-like intrinsic mesenchymal stem cell properties in long-term in vitro cultures. Moreover, the WJ-MSCs exhibited the in vitro multilineage differentiation capacity by giving rise to differentiated cells of not only mesodermal lineage but also to the cells of ectodermal and endodermal lineage. Also, WJ-MSC did not present any aberrant cell state upon in vivo transplantation in SCID mice and in vitro soft agar assays. The immunomodulatory potential assessed by gene expression levels of immunomodulatory factors upon exposure to inflammatory cytokines in the fetal WJ-MSCs was relatively higher compared to adult bone marrow-derived MSCs. WJ-MSCs seeded on decellularized amniotic membrane scaffold transplantation on the skin injury of SCID mice model demonstrates that combination of WJ-MSCs and decellularized amniotic membrane scaffold exhibited significantly better wound-healing capabilities, having reduced scar formation with hair growth and improved biomechanical properties of regenerated skin compared to WJ-MSCs alone. Further, our experimental data indicate that indocyanin green (ICG) at optimal concentration can be resourcefully used for labeling of stem cells and in vivo

  13. Human Wharton's Jelly Mesenchymal Stem Cells plasticity augments scar-free skin wound healing with hair growth.

    PubMed

    Sabapathy, Vikram; Sundaram, Balasubramanian; V M, Sreelakshmi; Mankuzhy, Pratheesh; Kumar, Sanjay

    2014-01-01

    Human mesenchymal stem cells (MSCs) are a promising candidate for cell-based transplantation and regenerative medicine therapies. Thus in the present study Wharton's Jelly Mesenchymal Stem Cells (WJ-MSCs) have been derived from extra embryonic umbilical cord matrix following removal of both arteries and vein. Also, to overcome the clinical limitations posed by fetal bovine serum (FBS) supplementation because of xenogeneic origin of FBS, usual FBS cell culture supplement has been replaced with human platelet lysate (HPL). Apart from general characteristic features of bone marrow-derived MSCs, wharton jelly-derived MSCs have the ability to maintain phenotypic attributes, cell growth kinetics, cell cycle pattern, in vitro multilineage differentiation plasticity, apoptotic pattern, normal karyotype-like intrinsic mesenchymal stem cell properties in long-term in vitro cultures. Moreover, the WJ-MSCs exhibited the in vitro multilineage differentiation capacity by giving rise to differentiated cells of not only mesodermal lineage but also to the cells of ectodermal and endodermal lineage. Also, WJ-MSC did not present any aberrant cell state upon in vivo transplantation in SCID mice and in vitro soft agar assays. The immunomodulatory potential assessed by gene expression levels of immunomodulatory factors upon exposure to inflammatory cytokines in the fetal WJ-MSCs was relatively higher compared to adult bone marrow-derived MSCs. WJ-MSCs seeded on decellularized amniotic membrane scaffold transplantation on the skin injury of SCID mice model demonstrates that combination of WJ-MSCs and decellularized amniotic membrane scaffold exhibited significantly better wound-healing capabilities, having reduced scar formation with hair growth and improved biomechanical properties of regenerated skin compared to WJ-MSCs alone. Further, our experimental data indicate that indocyanin green (ICG) at optimal concentration can be resourcefully used for labeling of stem cells and in vivo

  14. Growth and differentiation in cultured human thyroid cells: effects of epidermal growth factor and thyrotropin.

    PubMed

    Errick, J E; Ing, K W; Eggo, M C; Burrow, G N

    1986-01-01

    Human thyroid cells were grown and subcultured in vitro to examine their responses to known hormones and growth factors, and to serum. The cells were obtained from surgical specimens and were either neoplastic or nonneoplastic. The effects of culture conditions on cell growth were measured by changes in cell numbers and by stimulation of [3H]thymidine incorporation. The results showed that serum (0.5%) was essential for cell proliferation, and that a mixture of insulin (10 micrograms/ml), transferrin (5 micrograms/ml), hydrocortisone (10 micrograms/ml), somatostatin (10 ng/ml), and glycyl-histidyl-lysine (10 ng/ml) enhanced the effect of serum. Maximum growth of the cells was obtained when epidermal growth factor was present at 10(-9) M. Differentiation was measured by production of thyroglobulin, which was found to be stimulated by thyrotropin. This system provides a means to study the hormonal control of growth and differentiation in human thyroid cells. PMID:3511027

  15. Molecular mobility of scaffolds' biopolymers influences cell growth.

    PubMed

    Podlipec, Rok; Gorgieva, Selestina; Jurašin, Darija; Urbančič, Iztok; Kokol, Vanja; Strancar, Janez

    2014-09-24

    Understanding biocompatibility of materials and scaffolds is one of the main challenges in the field of tissue engineering and regeneration. The complex nature of cell-biomaterial interaction requires extensive preclinical functionality testing by studying specific cell responses to different biomaterial properties, from morphology and mechanics to surface characteristics at the molecular level. Despite constant improvements, a more general picture of biocompatibility is still lacking and tailormade scaffolds are not yet available. The scope of our study was thus the investigation of the correlation of fibroblast cell growth on different gelatin scaffolds with their morphological, mechanical as well as surface molecular properties. The latter were thoroughly investigated via polymer molecular mobility studied by site-directed spin labeling and electron paramagnetic resonance spectroscopy (EPR) for the first time. Anisotropy of the rotational motion of the gelatin side chain mobility was identified as the most correlated quantity with cell growth in the first days after adhesion, while weaker correlations were found with scaffold viscoelasticity and no correlations with scaffold morphology. Namely, the scaffolds with highly mobile or unrestricted polymers identified with the cell growth being five times less efficient (N(cells) = 60 ± 25 mm(-2)) as compared to cell growth on the scaffolds with considerable part of polymers with the restricted rotational motion (N(cells) = 290 ± 25 mm(-2)). This suggests that molecular mobility of scaffold components could play an important role in cell response to medical devices, reflecting a new aspect of the biocompatibility concept.

  16. Phosphoinositide turnover in cell growth and transformation

    SciTech Connect

    Fleischman, L.F.

    1987-01-01

    Interaction of cells with various stimuli triggers a common signal transduction pathway involving breakdown and resynthesis of the minor membrane lipid phosphatidylinositol-4,5-bisphosphate (PIP/sub 2/). Hydrolysis of PIP/sub 2/ by phospholipase C generates two key catabolites-inositol-1,4,5-trisphosphate (IP/sub 3/) and diacylglycerol (DAG)-which mediate and amplify cellular responses. These studies provide evidence for potential involvement of this pathway in oncogenic transformation and cell cycle progression. Altered levels of PIP/sub 2/ and its breakdown products were found in cells transformed by ras oncogenes, in contrast to untransformed counterparts. Steady-state levels of PIP/sub 2/, DAG and inositol phosphates were measured in NIH 3T3 and NRK cells metabolically labelled with /sup 3/H-glycerol and /sup 3/H-inositol. DAG and inositol phosphate levels were significantly elevated by 2.5-3 fold in the transformed cells while levels of PIP/sub 2/ were decreased. These findings suggest that the ras protein may activate phospholipase C. Elevated DAG content in the transformed cells was also measured by phosphorylation of DAG using a partially purified DAG kinase, indicating that the differences seen could not be attributed to differences in labelling between the cell lines.

  17. Molecular detection of noninvasive and invasive bladder tumor tissues and exfoliated cells by aberrant promoter methylation of laminin-5 encoding genes.

    PubMed

    Sathyanarayana, Ubaradka G; Maruyama, Riichiroh; Padar, Asha; Suzuki, Makoto; Bondaruk, Jolanta; Sagalowsky, Arthur; Minna, John D; Frenkel, Eugene P; Grossman, H Barton; Czerniak, Bogdan; Gazdar, Adi F

    2004-02-15

    Laminin-5 (LN5) anchors epithelial cells to the underlying basement membrane, and it is encoded by three distinct genes: LAMA3, LAMB3, and LAMC2. To metastasize and grow, cancer cells must invade and destroy the basement membrane. Our previous work has shown that epigenetic inactivation is a major mechanism of silencing LN5 genes in lung cancers. We extended our methylation studies to resected bladder tumors (n = 128) and exfoliated cell samples (bladder washes and voided urine; n = 71) and correlated the data with clinicopathologic findings. Nonmalignant urothelium had uniform expression of LN5 genes and lacked methylation. The methylation frequencies for LN5 genes in tumors were 21-45%, and there was excellent concordance between methylation in tumors and corresponding exfoliated cells. Methylation of LAMA3 and LAMB3 and the methylation index were correlated significantly with several parameters of poor prognosis (tumor grade, growth pattern, muscle invasion, tumor stage, and ploidy pattern), whereas methylation of LAMC2 and methylation index were associated with shortened patient survival. Of particular interest, methylation frequencies of LAMA3 helped to distinguish invasive (72%) from noninvasive (12%) tumors. These results suggest that methylation of LN5 genes has potential clinical applications in bladder cancers. PMID:14973053

  18. Tankyrase inhibitors attenuate WNT/β-catenin signaling and inhibit growth of hepatocellular carcinoma cells

    PubMed Central

    Ma, Li; Wang, Xiaolin; Jia, Tao; Wei, Wei; Chua, Mei-Sze; So, Samuel

    2015-01-01

    Deregulated WNT/β-catenin signaling contributes to the development of a subgroup of hepatocellular carcinoma (HCC), the second leading cause of cancer deaths worldwide. Within this pathway, the tankyrase enzymes (TNKS1 and TNKS2) degrade AXIN and thereby enhance β-catenin activity. We evaluate TNKS enzymes as potential therapeutic targets in HCC, and the anti-tumor efficacy of tankyrase inhibitors (XAV939, and its novel nitro-substituted derivative WXL-8) in HCC cells. Using semi-quantitative RT-PCR, we found significantly elevated levels of TNKS1/2 mRNA in tumor liver tissues compared to adjacent non-tumor livers, at protein levels only TNKS1 is increased. In HepG2, Huh7cells, siRNA-mediated knockdown suppression of endogenous TNKS1 and TNKS2 reduced cell proliferation, together with decreased nuclear β-catenin levels. XAV939 and WXL-8 inhibited cell proliferation and colony formation in HepG2, Huh7, and Hep40 cells (p < 0.05), with stabilization of AXIN1 and AXIN2, and decreased β-catenin protein levels. XAV939 and WXL-8 also attenuated rhWNT3A-induced TOPflash luciferase reporter activity in HCC cells, indicating reduced β-catenin transcriptional activity, consistent with decreased nuclear β-catenin levels. In vivo, intra-tumor injections of XAV939 or WXL-8 significantly inhibited the growth of subcutaneous HepG2 xenografts (P < 0.05). We suggest that tankyrase inhibition is a potential therapeutic approach for treating a subgroup HCC with aberrant WNT/β-catenin signaling pathway. PMID:26246473

  19. Phenotype of proliferating cells stimulated during compensatory adrenal growth.

    PubMed

    Holzwarth, M A; Gomez-Sanchez, C E; Engeland, W C

    1996-11-01

    The phenotype of the proliferating cells during adrenocortical growth has remained controversial although glomerulosa, fasciculata and intermediate zone cells have all been considered possible candidates. This was due in part to the inability to identify specific adrenocortical cell types in comparing different types of growth. In the present studies, using immunocytochemical localization of cytochrome P450 aldosterone synthase (P450aldo) and cytochrome P450 11 beta-hydroxylase (P45011 beta) to identify adrenocortical cell phenotypes as well as Ki-67 to label proliferating cells, we have investigated the phenotype of the proliferating cells in the compensatory adrenal growth response to unilateral adrenalectomy. Between 24 and 96 hrs after unilateral adrenalectomy, most Ki-67(+) nuclei were found in the outermost region of the fasciculata, as defined by P45011 beta immunoreactive cells. Few Ki-67(+) nuclei were found in the glomerulosa, defined by P450aldo cells or in the z intermedia, identified by the absence of both P450aldo and P45011 beta. To test which cell type is activated by unilateral adrenalectomy, we altered the phenotypic configuration of the adrenal cortex; rats were placed on a low Na+ diet for three weeks, resulting in a marked expansion of the number of P450aldo(+) cells. An abundance of proliferating cells was identified primarily in the expanded glomerulosa, but not in the intermedia or fasciculata. In contrast, the proliferation associated with compensatory growth in these low Na+ rats, was localized primarily in the outer P45011 beta(+) zone. These findings suggest that the phenotype of the proliferating cell is specific to the growth promoting stimulus.

  20. Unicellular Algal Growth: A Biomechanical Approach to Cell Wall Dynamics

    NASA Astrophysics Data System (ADS)

    Kam, Royce; Levine, Herbert

    1997-11-01

    We model a growing cell in a calcium solution as an elastic shell on short time scales. The turgor pressure and elastic properties (Young's modulus, thickness) of the cell wall determine a stressed cell shape. Enzyme-mediated relaxation of the unstressed toward the stressed configuration results in a slow (plastic) deformation of the cell. The cell wall thickness is then modulated by calcium-mediated fusion of material and elongation. We analyze small perturbations to a circular cell and find an instability related to modulations of the wall thickness, leading to growth rates which peak at a finite wave number.

  1. Growth-stimulatory effect of resveratrol in human cancer cells.

    PubMed

    Fukui, Masayuki; Yamabe, Noriko; Kang, Ki Sung; Zhu, Bao Ting

    2010-08-01

    Earlier studies have shown that resveratrol could induce death in several human cancer cell lines in culture. Here we report our observation that resveratrol can also promote the growth of certain human cancer cells when they are grown either in culture or in athymic nude mice as xenografts. At relatively low concentrations (growth-stimulatory effect in the MDA-MB-435s human cancer cells, but this effect was not observed in several other human cell lines tested. Analysis of cell signaling molecules showed that resveratrol induced the activation of JNK, p38, Akt, and NF-kappaB signaling pathways in these cells. Further analysis using pharmacological inhibitors showed that only the NF-kappaB inhibitor (BAY11-7082) abrogated the growth-stimulatory effect of resveratrol in cultured cells. In athymic nude mice, resveratrol at 16.5 mg/kg body weight enhanced the growth of MDA-MB-435s xenografts compared to the control group, while resveratrol at the 33 mg/kg body weight dose did not have a similar effect. Additional analyses confirmed that resveratrol stimulated cancer cell growth in vivo through activation of the NF-kappaB signaling pathway. Taken together, these observations suggest that resveratrol at low concentrations could stimulate the growth of certain types of human cancer cells in vivo. This cell type-specific mitogenic effect of resveratrol may also partly contribute to the procarcinogenic effect of alcohol consumption (rich in resveratrol) in the development of certain human cancers.

  2. SPARC promotes leukemic cell growth and predicts acute myeloid leukemia outcome

    PubMed Central

    Alachkar, Houda; Santhanam, Ramasamy; Maharry, Kati; Metzeler, Klaus H.; Huang, Xiaomeng; Kohlschmidt, Jessica; Mendler, Jason H.; Benito, Juliana M.; Hickey, Christopher; Neviani, Paolo; Dorrance, Adrienne M.; Anghelina, Mirela; Khalife, Jihane; Tarighat, Somayeh S.; Volinia, Stefano; Whitman, Susan P.; Paschka, Peter; Hoellerbauer, Pia; Wu, Yue-Zhong; Han, Lina; Bolon, Brad N.; Blum, William; Mrózek, Krzysztof; Carroll, Andrew J.; Perrotti, Danilo; Andreeff, Michael; Caligiuri, Michael A.; Konopleva, Marina; Garzon, Ramiro; Bloomfield, Clara D.; Marcucci, Guido

    2014-01-01

    Aberrant expression of the secreted protein, acidic, cysteine-rich (osteonectin) (SPARC) gene, which encodes a matricellular protein that participates in normal tissue remodeling, is associated with a variety of diseases including cancer, but the contribution of SPARC to malignant growth remains controversial. We previously reported that SPARC was among the most upregulated genes in cytogenetically normal acute myeloid leukemia (CN-AML) patients with gene-expression profiles predictive of unfavorable outcome, such as mutations in isocitrate dehydrogenase 2 (IDH2-R172) and overexpression of the oncogenes brain and acute leukemia, cytoplasmic (BAALC) and v-ets erythroblastosis virus E26 oncogene homolog (ERG). In contrast, SPARC was downregulated in CN-AML patients harboring mutations in nucleophosmin (NPM1) that are associated with favorable prognosis. Based on these observations, we hypothesized that SPARC expression is clinically relevant in AML. Here, we found that SPARC overexpression is associated with adverse outcome in CN-AML patients and promotes aggressive leukemia growth in murine models of AML. In leukemia cells, SPARC expression was mediated by the SP1/NF-κB transactivation complex. Furthermore, secreted SPARC activated the integrin-linked kinase/AKT (ILK/AKT) pathway, likely via integrin interaction, and subsequent β-catenin signaling, which is involved in leukemia cell self-renewal. Pharmacologic inhibition of the SP1/NF-κB complex resulted in SPARC downregulation and leukemia growth inhibition. Together, our data indicate that evaluation of SPARC expression has prognosticative value and SPARC is a potential therapeutic target for AML. PMID:24590286

  3. Prolonged cyclic strain inhibits human endothelial cell growth.

    PubMed

    Peyton, Kelly J; Liu, Xiao-ming; Durante, William

    2016-01-01

    The vascular endothelium is continuously exposed to cyclic mechanical strain due to the periodic change in vessel diameter as a result of pulsatile blood flow. Since emerging evidence indicates the cyclic strain plays an integral role in regulating endothelial cell function, the present study determined whether application of a physiologic regimen of cyclic strain (6% at 1 hertz) influences the proliferation of human arterial endothelial cells. Prolonged exposure of human dermal microvascular or human aortic endothelial cells to cyclic strain for up to 7 days resulted in a marked decrease in cell growth. The strain-mediated anti-proliferative effect was associated with the arrest of endothelial cells in the G2/M phase of the cell cycle, did not involve cell detachment or cytotoxicity, and was due to the induction of p21. Interestingly, the inhibition in endothelial cell growth was independent of the strain regimen since prolonged application of constant or intermittent 6% strain was also able to block endothelial cell proliferation. The ability of chronic physiologic cyclic strain to inhibit endothelial cell growth represents a previously unrecognized mechanism by which hemodynamic forces maintain these cells in a quiescent, non-proliferative state. PMID:26709656

  4. Rheumatoid synovial cells from intact joints. Morphology, growth, and polykaryocytosis.

    PubMed

    Clarris, B J; Fraser, J R; Moran, C J; Muirden, K D

    1977-08-01

    Synovial cell lines were isolated by instillation of trypsin or chymotrypsin into intact knee joints of patients with persistent rheumatoid effusions resistant to conventional therapy. Morphology and growth in the primary phase were compared with rheumatoid cells isolated from excised synovium and nonrheumatoid synovial cells obtained from intact joints of cadavers or amputated limbs. Cell populations from all sources included varying proportions of macrophage-like and fibroblast-like cells, with only 1-3% multinucleated cells. In medium supplemented with calf serum alone, rheumatoid cells from intact joints showed negligible changes in morphology. However, in the presence of nonrheumatoid, autologous rheumatoid or homologous rheumatoid serum a rapid increase occurred in size of the macrophage-like cells and numbers of polykaryocytes, including some giant syncytial cells. These effects were directly proportional to serum concentration and were identical in fresh or heat-inactivated serum. In most of these rheumatoid cell lines no multiplication occurred, regardless of serum type or concentration. In rheumatoid synovial cells from excised synovium, human serum induced both polykaryocytosis and rapid growth of fibroblasts. Nonrheumatoid synovial cells grew rapidly but few polykaryocytes developed, mostly with less than 6 nuclei. Evidence of viral infection in rheumatoid synovial cells was sought by electron microscopy after stimulation of polykaryocytosis by human serum. In one of the cultures many cells were found with intranuclear particles possessing characteristics of the adenovirus group. PMID:901027

  5. Ubiquitin-specific protease 4 inhibits breast cancer cell growth through the upregulation of PDCD4

    PubMed Central

    Li, Yang; Jiang, Daqing; Zhang, Qi; Liu, Xiaoli; Cai, Zhengang

    2016-01-01

    Breast cancer is a common malignant tumor affecting women. The study of the association between breast cancer and molecular aberrations may lead to the development of novel diagnostic and therapeutic strategies for the disease. In the present study, we examined the role of ubiquitin-specific protease 4 (USP4) in breast cancer. We found that USP4 expression was significantly decreased in breast cancer tissue samples compared with paired normal breast tissue samples (P<0.001). USP4 was identified as a tumor suppressor. In addition, by inducing USP4 overexpression (using a USP4 overexpression plasmid) or the knockdown of USP4 (by transfection with a USP4 shRNA plasmid), we found that USP4 inhibited cell proliferation in vitro. We also found that USP4 suppressed tumor growth by using a mouse tumor xenograft model. Moreover, programmed cell death 4 (PCD4) was identified to be a target of USP4, which plays a role as a tumor suppressor. As a whole, our findings sugggest that USP4 acts as a tumor suppressor in breast cancer and that it may be an effective target for the treatment of breast cancer. PMID:27430936

  6. A study of cell electrophoresis as a means of purifying growth hormone secreting cells

    NASA Technical Reports Server (NTRS)

    Plank, Lindsay D.; Hymer, W. C.; Kunze, M. Elaine; Marks, Gary M.; Lanham, J. Wayne

    1983-01-01

    Growth hormone secreting cells of the rat anterior pituitary are heavily laden with granules of growth hormone and can be partialy purified on the basis of their resulting high density. Two methods of preparative cell electrophoresis were investigated as methods of enhancing the purification of growth hormone producing cells: density gradient electrophoresis and continuous flow electrophoresis. Both methods provided a two- to four-fold enrichment in growth hormone production per cell relative to that achieved by previous methods. Measurements of electrophoretic mobilities by two analytical methods, microscopic electrophoresis and laser-tracking electrophoresis, revealed very little distinction between unpurified anterior pituitary cell suspensions and somatotroph-enriched cell suspensions. Predictions calculated on the basis of analytical electrophoretic data are consistent with the hypothesis that sedimentation plays a significant role in both types of preparative electrophoresis and the electrophoretic mobility of the growth hormone secreting subpopulation of cells remains unknown.

  7. Role of growth factors in the growth of normal and transformed cells

    SciTech Connect

    Lokeshwar, V.B.

    1989-01-01

    Growth factors play an important role in the growth of normal cells. However, their untimely and/or excess production leads to neoplastic transformation. The role of growth factors in the growth of normal cells was studied by investigating the mechanism of transmodulation of the cell surface EGF receptor number by protamine. Protamine increased the EGF stimulated mitogenic response in Swiss mouse 3T3 cells and A431 cells by increasing the number of functionally active EGF receptors. Protamine also increased EGF receptor number in plasma membranes and solubilized membranes. This was evidenced by an increase in both {sup 125}I-EGF-EGF-receptor complex and EGF stimulated phosphorylation of the EGF receptor. The solubilized EGF receptor was retained on a protamine-agarose gel indicating that protamine might increase EGF receptor number by directly activating cryptic EGF receptors in the plasma membranes. The role of growth factors in neoplastic transformation was studied by investigating the role of the oncogene v-sis in the growth of Simian sarcoma virus (SSV) transformed cells. The product of the oncogene v-sis is 94% homologous to the B chain of PDGF. This study found that (i) v-sis gene product is synthesized as a 32 kDa unglycosylated monomer which is glycosylated, dimerized and proteolytically processed into p36, p72, p68, p58, p44 and p27 mol. wt. species respectively. (ii) p36, p72, p68 and p58 are very likely formed in the endoplasmic reticulum and/or Golgi complex. A fraction of newly synthesized p72, p68 and p58 is degraded intracellularly at a fast rate. (iii) p44 is a secretory product which remains tightly associated with the cell surface. p44 is recaptured by the cells through interaction with cell surface PDGF receptors and degraded into p27. (iv) During long term cultures p44 is extracellularly cleaved into a 27 kDa product.

  8. Assaying binding of nerve growth factor to cell surface receptors

    SciTech Connect

    Vale, R.D.; Shooter, E.M.

    1985-01-01

    The paper describes methods both for the radioiodination of nerve growth factor (NGF) and for assaying NFG receptors by reversible binding techniques. Preparation of (/sup 125/I)NGF along with a rapid method for determining the amount of cell-bound ligand have allowed the detection of NGF receptors on a number of cell types.

  9. ROS Regulation of Polar Growth in Plant Cells1[OPEN

    PubMed Central

    Mangano, Silvina; Juárez, Silvina Paola Denita

    2016-01-01

    Root hair cells and pollen tubes, like fungal hyphae, possess a typical tip or polar cell expansion with growth limited to the apical dome. Cell expansion needs to be carefully regulated to produce a correct shape and size. Polar cell growth is sustained by oscillatory feedback loops comprising three main components that together play an important role regulating this process. One of the main components are reactive oxygen species (ROS) that, together with calcium ions (Ca2+) and pH, sustain polar growth over time. Apoplastic ROS homeostasis controlled by NADPH oxidases as well as by secreted type III peroxidases has a great impact on cell wall properties during cell expansion. Polar growth needs to balance a focused secretion of new materials in an extending but still rigid cell wall in order to contain turgor pressure. In this review, we discuss the gaps in our understanding of how ROS impact on the oscillatory Ca2+ and pH signatures that, coordinately, allow root hair cells and pollen tubes to expand in a controlled manner to several hundred times their original size toward specific signals. PMID:27208283

  10. c-Met–mediated endothelial plasticity drives aberrant vascularization and chemoresistance in glioblastoma

    PubMed Central

    Huang, Menggui; Liu, Tianrun; Ma, Peihong; Mitteer, R. Alan; Zhang, Zhenting; Kim, Hyun Jun; Yeo, Eujin; Zhang, Duo; Cai, Peiqiang; Li, Chunsheng; Zhang, Lin; Zhao, Botao; Roccograndi, Laura; O’Rourke, Donald M.; Dahmane, Nadia; Gong, Yanqing; Koumenis, Constantinos

    2016-01-01

    Aberrant vascularization is a hallmark of cancer progression and treatment resistance. Here, we have shown that endothelial cell (EC) plasticity drives aberrant vascularization and chemoresistance in glioblastoma multiforme (GBM). By utilizing human patient specimens, as well as allograft and genetic murine GBM models, we revealed that a robust endothelial plasticity in GBM allows acquisition of fibroblast transformation (also known as endothelial mesenchymal transition [Endo-MT]), which is characterized by EC expression of fibroblast markers, and determined that a prominent population of GBM-associated fibroblast-like cells have EC origin. Tumor ECs acquired the mesenchymal gene signature without the loss of EC functions, leading to enhanced cell proliferation and migration, as well as vessel permeability. Furthermore, we identified a c-Met/ETS-1/matrix metalloproteinase–14 (MMP-14) axis that controls VE-cadherin degradation, Endo-MT, and vascular abnormality. Pharmacological c-Met inhibition induced vessel normalization in patient tumor–derived ECs. Finally, EC-specific KO of Met inhibited vascular transformation, normalized blood vessels, and reduced intratumoral hypoxia, culminating in suppressed tumor growth and prolonged survival in GBM-bearing mice after temozolomide treatment. Together, these findings illustrate a mechanism that controls aberrant tumor vascularization and suggest that targeting Endo-MT may offer selective and efficient strategies for antivascular and vessel normalization therapies in GBM, and possibly other malignant tumors. PMID:27043280

  11. Chromosome Aberrations in Astronauts

    NASA Technical Reports Server (NTRS)

    George, Kerry A.; Durante, M.; Cucinotta, Francis A.

    2007-01-01

    A review of currently available data on in vivo induced chromosome damage in the blood lymphocytes of astronauts proves that, after protracted exposure of a few months or more to space radiation, cytogenetic biodosimetry analyses of blood collected within a week or two of return from space provides a reliable estimate of equivalent radiation dose and risk. Recent studies indicate that biodosimetry estimates from single spaceflights lie within the range expected from physical dosimetry and biophysical models, but very large uncertainties are associated with single individual measurements and the total sample population remains low. Retrospective doses may be more difficult to estimate because of the fairly rapid time-dependent loss of "stable" aberrations in blood lymphocytes. Also, biodosimetry estimates from individuals who participate in multiple missions, or very long (interplanetary) missions, may be complicated by an adaptive response to space radiation and/or changes in lymphocyte survival and repopulation. A discussion of published data is presented and specific issues related to space radiation biodosimetry protocols are discussed.

  12. A human monoclonal antibody targeting the stem cell factor receptor (c-Kit) blocks tumor cell signaling and inhibits tumor growth.

    PubMed

    Lebron, Maria B; Brennan, Laura; Damoci, Christopher B; Prewett, Marie C; O'Mahony, Marguerita; Duignan, Inga J; Credille, Kelly M; DeLigio, James T; Starodubtseva, Marina; Amatulli, Michael; Zhang, Yiwei; Schwartz, Kaben D; Burtrum, Douglas; Balderes, Paul; Persaud, Kris; Surguladze, David; Loizos, Nick; Paz, Keren; Kotanides, Helen

    2014-09-01

    Stem cell factor receptor (c-Kit) exerts multiple biological effects on target cells upon binding its ligand stem cell factor (SCF). Aberrant activation of c-Kit results in dysregulated signaling and is implicated in the pathogenesis of numerous cancers. The development of more specific and effective c-Kit therapies is warranted given its essential role in tumorigenesis. In this study, we describe the biological properties of CK6, a fully human IgG1 monoclonal antibody against the extracellular region of human c-Kit. CK6 specifically binds c-Kit receptor with high affinity (EC 50 = 0.06 nM) and strongly blocks its interaction with SCF (IC 50 = 0.41 nM) in solid phase assays. Flow cytometry shows CK6 binding to c-Kit on the cell surface of human small cell lung carcinoma (SCLC), melanoma, and leukemia tumor cell lines. Furthermore, exposure to CK6 inhibits SCF stimulation of c-Kit tyrosine kinase activity and downstream signaling pathways such as mitogen-activated protein kinase (MAPK) and protein kinase B (AKT), in addition to reducing tumor cell line growth in vitro. CK6 treatment significantly decreases human xenograft tumor growth in NCI-H526 SCLC (T/C% = 57) and Malme-3M melanoma (T/C% = 58) models in vivo. The combination of CK6 with standard of care chemotherapy agents, cisplatin and etoposide for SCLC or dacarbazine for melanoma, more potently reduces tumor growth (SCLC T/C% = 24, melanoma T/C% = 38) compared with CK6 or chemotherapy alone. In summary, our results demonstrate that CK6 is a c-Kit antagonist antibody with tumor growth neutralizing properties and are highly suggestive of potential therapeutic application in treating human malignancies harboring c-Kit receptor. PMID:24921944

  13. In vitro melanoma cell growth after preenucleation radiation therapy

    SciTech Connect

    Kenneally, C.Z.; Farber, M.G.; Smith, M.E.; Devineni, R.

    1988-02-01

    The in vitro efficacy of 20 Gy (2000 rad) of external beam irradiation delivered to patients with choroidal melanomas prior to enucleation was investigated in 11 patients whose tumors were grown in cell culture. Phase-contrast microscopy was used to compare growth patterns between irradiated and nonirradiated tumors. Cell types were determined by histologic stains, and electron microscopy identified intracytoplasmic melanin. Irradiated melanomas did not grow and did not attach to culture flasks, thus demonstrating that preenucleation irradiation alters the in vitro growth of melanoma cells.

  14. Pumpkin seed extract: Cell growth inhibition of hyperplastic and cancer cells, independent of steroid hormone receptors.

    PubMed

    Medjakovic, Svjetlana; Hobiger, Stefanie; Ardjomand-Woelkart, Karin; Bucar, Franz; Jungbauer, Alois

    2016-04-01

    Pumpkin seeds have been known in folk medicine as remedy for kidney, bladder and prostate disorders since centuries. Nevertheless, pumpkin research provides insufficient data to back up traditional beliefs of ethnomedical practice. The bioactivity of a hydro-ethanolic extract of pumpkin seeds from the Styrian pumpkin, Cucurbita pepo L. subsp. pepo var. styriaca, was investigated. As pumpkin seed extracts are standardized to cucurbitin, this compound was also tested. Transactivational activity was evaluated for human androgen receptor, estrogen receptor and progesterone receptor with in vitro yeast assays. Cell viability tests with prostate cancer cells, breast cancer cells, colorectal adenocarcinoma cells and a hyperplastic cell line from benign prostate hyperplasia tissue were performed. As model for non-hyperplastic cells, effects on cell viability were tested with a human dermal fibroblast cell line (HDF-5). No transactivational activity was found for human androgen receptor, estrogen receptor and progesterone receptor, for both, extract and cucurbitin. A cell growth inhibition of ~40-50% was observed for all cell lines, with the exception of HDF-5, which showed with ~20% much lower cell growth inhibition. Given the receptor status of some cell lines, a steroid-hormone receptor independent growth inhibiting effect can be assumed. The cell growth inhibition for fast growing cells together with the cell growth inhibition of prostate-, breast- and colon cancer cells corroborates the ethnomedical use of pumpkin seeds for a treatment of benign prostate hyperplasia. Moreover, due to the lack of androgenic activity, pumpkin seed applications can be regarded as safe for the prostate.

  15. Blockade of Hedgehog Signaling Synergistically Increases Sensitivity to Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors in Non-Small-Cell Lung Cancer Cell Lines.

    PubMed

    Bai, Xiao-Yan; Zhang, Xu-Chao; Yang, Su-Qing; An, She-Juan; Chen, Zhi-Hong; Su, Jian; Xie, Zhi; Gou, Lan-Ying; Wu, Yi-Long

    2016-01-01

    Aberrant activation of the hedgehog (Hh) signaling pathway has been implicated in the epithelial-to-mesenchymal transition (EMT) and cancer stem-like cell (CSC) maintenance; both processes can result in tumor progression and treatment resistance in several types of human cancer. Hh cooperates with the epidermal growth factor receptor (EGFR) signaling pathway in embryogenesis. We found that the Hh signaling pathway was silenced in EGFR-TKI-sensitive non-small-cell lung cancer (NSCLC) cells, while it was inappropriately activated in EGFR-TKI-resistant NSCLC cells, accompanied by EMT induction and ABCG2 overexpression. Upregulation of Hh signaling through extrinsic SHH exposure downregulated E-cadherin expression and elevated Snail and ABCG2 expression, resulting in gefitinib tolerance (P < 0.001) in EGFR-TKI-sensitive cells. Blockade of the Hh signaling pathway using the SMO antagonist SANT-1 restored E-cadherin expression and downregulate Snail and ABCG2 in EGFR-TKI-resistant cells. A combination of SANT-1 and gefitinib markedly inhibited tumorigenesis and proliferation in EGFR-TKI-resistant cells (P < 0.001). These findings indicate that hyperactivity of Hh signaling resulted in EGFR-TKI resistance, by EMT introduction and ABCG2 upregulation, and blockade of Hh signaling synergistically increased sensitivity to EGFR-TKIs in primary and secondary resistant NSCLC cells. E-cadherin expression may be a potential biomarker of the suitability of the combined application of an Hh inhibitor and EGFR-TKIs in EGFR-TKI-resistant NSCLCs. PMID:26943330

  16. Correction of Distributed Optical Aberrations

    SciTech Connect

    Baker, K; Olivier, S; Carrano, C; Phillion, D

    2006-02-12

    The objective of this project was to demonstrate the use of multiple distributed deformable mirrors (DMs) to improve the performance of optical systems with distributed aberrations. This concept is expected to provide dramatic improvement in the optical performance of systems in applications where the aberrations are distributed along the optical path or within the instrument itself. Our approach used multiple actuated DMs distributed to match the aberration distribution. The project developed the algorithms necessary to determine the required corrections and simulate the performance of these multiple DM systems.

  17. Mast cells, angiogenesis, and tumour growth.

    PubMed

    Ribatti, Domenico; Crivellato, Enrico

    2012-01-01

    Accumulation of mast cells (MCs) in tumours was described by Ehrlich in his doctoral thesis. Since this early account, ample evidence has been provided highlighting participation of MCs to the inflammatory reaction that occurs in many clinical and experimental tumour settings. MCs are bone marrow-derived tissue-homing leukocytes that are endowed with a panoply of releasable mediators and surface receptors. These cells actively take part to innate and acquired immune reactions as well as to a series of fundamental functions such as angiogenesis, tissue repair, and tissue remodelling. The involvement of MCs in tumour development is debated. Although some evidence suggests that MCs can promote tumourigenesis and tumour progression, there are some clinical sets as well as experimental tumour models in which MCs seem to have functions that favour the host. One of the major issues linking MCs to cancer is the ability of these cells to release potent pro-angiogenic factors. This review will focus on the most recent acquisitions about this intriguing field of research. This article is part of a Special Issue entitled: Mast cells in inflammation.

  18. Growth of respiratory syncytial virus in mink lung epithelial cells.

    PubMed

    Yeolekar, L R; Damle, R G; Basu, A; Rao, B L

    2002-12-01

    Mink lung epithelial cells (Mv-1-Lu) were tested for their ability to support the growth and serial passage of respiratory syncytial virus (RSV) in vitro. Indian isolates of RSV induced distinctive cytopathic effect with typical rounding of cells followed by detachment with more than 50 per cent cells showing bright fluorescence using anti-RSV monoclonal antibodies in immunofluorescence test. Serial passage of RSV was possible in Mv-1-Lu cells without loss of sensitivity of the cells for virus growth. Titration of cell associated virus and virus released in the supernatant indicated that 60 per cent of the virus was released in the supernatant, and 40 per cent remained cell associated. Transmission electron microscopic studies of negatively stained RSV particles and ultra-thin sections of RSV infected Mv-1-Lu cells showed roughly spherical particles with club shaped projections, budding from the cytoplasmic membrane. These results indicate that Mv-1-Lu cell line is suitable for the growth and propagation of RSV.

  19. Growth hormone replacement in patients with Langerhan's cell histiocytosis

    PubMed Central

    Howell, S; Wilton, P; Shalet, S

    1998-01-01

    OBJECTIVES—To assess the impact of growth hormone on growth and the underlying disease in children with growth hormone deficiency as a result of Langerhan's cell histiocytosis.
STUDY DESIGN—Retrospective analysis of data from the Kabi (Pharmacia & Upjohn) international growth database (KIGS) for 82 children with Langerhan's cell histiocytosis treated with recombinant growth hormone.
RESULTS—At the start of treatment the median (10-90th centile) age was 9.0 (5.2 to 14.7) years, with a median height standard deviation score (SDS) of −2.0 (−3.5 to −0.9). The median pretreatment height velocity (measured in cm/year) was 3.6 (0.9 to 6.4); this increased to 8.8 (3.8 to 12.0) in the first year of treatment with growth hormone, and then remained significantly greater than the pretreatment height velocity at 7.3 (4.4 to 9.7) and 7.1 (4.1 to 9.3) cm/year in the second and third years, respectively. The median height SDS increased from −2.0 to −0.8 (−2.3 to 0.6) by the end of three years of treatment. There was no increase in the recurrence rate of the underlying disease and no adverse event could be directly attributed to growth hormone treatment, apart from one case of benign intracranial hypertension that resolved on stopping treatment with growth hormone.
CONCLUSIONS—Growth hormone replacement treatment for patients with Langerhan's cell histiocytosis with growth hormone deficiency is beneficial and safe.

 PMID:9659097

  20. When Cells Collide: A Model for Cell-Assisted Cell Growth based on Direct Contacts

    NASA Astrophysics Data System (ADS)

    Franck, Carl; Ip, Wui; Bae, Albert; Franck, Nathan; Bogart, Elijah; Thi Le, Thanhbinh

    2008-03-01

    Although intercellular communication is frequently viewed as involving the transport of small molecules through an intracellular fluid medium, biologists have proposed chemical signaling with chemical specificity due to chemical recognition through direct contacts. Considering the collective computation behind the decision of a cell to divide when it senses the presence of a sufficient number of like neighbors, we offer a model for the transition from slow to exponential growth in shaken suspension cell culture of the model eukaryote, Dictyostelium discoideum. Besides exploring an elegantly simple example of multicellular life, this discussion might well prove useful in considering the limits of cell culture on small spatial scales as required for contemporary massively parallel biotechnology.

  1. The oncogenic BRD4-NUT chromatin regulator drives aberrant transcription within large topological domains

    PubMed Central

    Alekseyenko, Artyom A.; Walsh, Erica M.; Wang, Xin; Grayson, Adlai R.; Hsi, Peter T.; Kharchenko, Peter V.; Kuroda, Mitzi I.; French, Christopher A.

    2015-01-01

    NUT midline carcinoma (NMC), a subtype of squamous cell cancer, is one of the most aggressive human solid malignancies known. NMC is driven by the creation of a translocation oncoprotein, BRD4-NUT, which blocks differentiation and drives growth of NMC cells. BRD4-NUT forms distinctive nuclear foci in patient tumors, which we found correlate with ∼100 unprecedented, hyperacetylated expanses of chromatin that reach up to 2 Mb in size. These “megadomains” appear to be the result of aberrant, feed-forward loops of acetylation and binding of acetylated histones that drive transcription of underlying DNA in NMC patient cells and naïve cells induced to express BRD4-NUT. Megadomain locations are typically cell lineage-specific; however, the cMYC and TP63 regions are targeted in all NMCs tested and play functional roles in tumor growth. Megadomains appear to originate from select pre-existing enhancers that progressively broaden but are ultimately delimited by topologically associating domain (TAD) boundaries. Therefore, our findings establish a basis for understanding the powerful role played by large-scale chromatin organization in normal and aberrant lineage-specific gene transcription. PMID:26220994

  2. Phase aberration effects in elastography.

    PubMed

    Varghese, T; Bilgen, M; Ophir, J

    2001-06-01

    In sonography, phase aberration plays a role in the corruption of sonograms. Phase aberration does not have a significant impact on elastography, if statistically similar phase errors are present in both the pre- and postcompression signals. However, if the phase errors are present in only one of the pre- or postcompression signal pairs, the precision of the strain estimation process will be reduced. In some cases, increased phase errors may occur only in the postcompression signal due to changes in the tissue structure with the applied compression. Phase-aberration effects increase with applied strain and may be viewed as an image quality derating factor, much like frequency-dependent attenuation or undesired lateral tissue motion. In this paper, we present a theoretical and simulation study of the effects of phase aberration on the elastographic strain-estimation process, using the strain filter approach.

  3. Total triterpenoids from Ganoderma Lucidum suppresses prostate cancer cell growth by inducing growth arrest and apoptosis.

    PubMed

    Wang, Tao; Xie, Zi-ping; Huang, Zhan-sen; Li, Hao; Wei, An-yang; Di, Jin-ming; Xiao, Heng-jun; Zhang, Zhi-gang; Cai, Liu-hong; Tao, Xin; Qi, Tao; Chen, Di-ling; Chen, Jun

    2015-10-01

    In this study, one immortalized human normal prostatic epithelial cell line (BPH) and four human prostate cancer cell lines (LNCaP, 22Rv1, PC-3, and DU-145) were treated with Ganoderma Lucidum triterpenoids (GLT) at different doses and for different time periods. Cell viability, apoptosis, and cell cycle were analyzed using flow cytometry and chemical assays. Gene expression and binding to DNA were assessed using real-time PCR and Western blotting. It was found that GLT dose-dependently inhibited prostate cancer cell growth through induction of apoptosis and cell cycle arrest at G1 phase. GLT-induced apoptosis was due to activation of Caspases-9 and -3 and turning on the downstream apoptotic events. GLT-induced cell cycle arrest (mainly G1 arrest) was due to up-regulation of p21 expression at the early time and down-regulation of cyclin-dependent kinase 4 (CDK4) and E2F1 expression at the late time. These findings demonstrate that GLT suppresses prostate cancer cell growth by inducing growth arrest and apoptosis, which might suggest that GLT or Ganoderma Lucidum could be used as a potential therapeutic drug for prostate cancer. PMID:26489631

  4. Total triterpenoids from Ganoderma Lucidum suppresses prostate cancer cell growth by inducing growth arrest and apoptosis.

    PubMed

    Wang, Tao; Xie, Zi-ping; Huang, Zhan-sen; Li, Hao; Wei, An-yang; Di, Jin-ming; Xiao, Heng-jun; Zhang, Zhi-gang; Cai, Liu-hong; Tao, Xin; Qi, Tao; Chen, Di-ling; Chen, Jun

    2015-10-01

    In this study, one immortalized human normal prostatic epithelial cell line (BPH) and four human prostate cancer cell lines (LNCaP, 22Rv1, PC-3, and DU-145) were treated with Ganoderma Lucidum triterpenoids (GLT) at different doses and for different time periods. Cell viability, apoptosis, and cell cycle were analyzed using flow cytometry and chemical assays. Gene expression and binding to DNA were assessed using real-time PCR and Western blotting. It was found that GLT dose-dependently inhibited prostate cancer cell growth through induction of apoptosis and cell cycle arrest at G1 phase. GLT-induced apoptosis was due to activation of Caspases-9 and -3 and turning on the downstream apoptotic events. GLT-induced cell cycle arrest (mainly G1 arrest) was due to up-regulation of p21 expression at the early time and down-regulation of cyclin-dependent kinase 4 (CDK4) and E2F1 expression at the late time. These findings demonstrate that GLT suppresses prostate cancer cell growth by inducing growth arrest and apoptosis, which might suggest that GLT or Ganoderma Lucidum could be used as a potential therapeutic drug for prostate cancer.

  5. Chloroquine inhibits cell growth and induces cell death in A549 lung cancer cells.

    PubMed

    Fan, Chuandong; Wang, Weiwei; Zhao, Baoxiang; Zhang, Shangli; Miao, Junying

    2006-05-01

    To investigate the effects of chloroquine diphosphate (CQ) on lung cancer cell growth, we treated A549 cells, a lung cancer cell line, with the drug at various concentrations (0.25-128 microM) for 24-72 h. The results showed that, at lower concentrations (from 0.25 to 32 microM), CQ inhibited the growth of A549 cells and, at the same time, it induced vacuolation with increased volume of acidic compartments (VAC). On the other hand, at higher concentrations (64-128 microM), CQ induced apoptosis at 24 h, while its effect of inducing vacuolation declined. The lactate dehydrogenase (LDH) assay showed that with the treatment of CQ 32-64 microM for 72 h or 128 microM for 48 h, CQ induced necrosis of A549 cells. To understand the possible mechanism by which CQ acts in A549 cells, we further incubated the cells with this drug at the concentrations of 32 or 128 microM in the presence of D609, a specific inhibitor of phosphatidylcholine-specific phospholipase C (PC-PLC). The results showed that D609 (50 microM) could inhibit the effects of CQ 32 microM on the viability and VAC, but it could not change the effects of CQ 128 microM on the same. Our data suggested that CQ inhibited A549 lung cancer cell growth at lower concentrations by increasing the volume of lysosomes and that PC-PLC might be involved in this process. The data also indicated that, at higher concentrations, CQ induced apoptosis and necrosis, but at this time its ability to increase the volume of lysosome gradually declined, and PC-PLC might not be implicated in the process. PMID:16413786

  6. SIAH-1 inhibits cell growth by altering the mitotic process.

    PubMed

    Bruzzoni-Giovanelli, H; Faille, A; Linares-Cruz, G; Nemani, M; Le Deist, F; Germani, A; Chassoux, D; Millot, G; Roperch, J P; Amson, R; Telerman, A; Calvo, F

    1999-11-25

    SIAH-1, the human homologue of the drosophila seven in absentia gene, is a p53-p21Waf-1 inducible gene. We report that stable transfection with SIAH-1 of the epithelial breast cancer cell line MCF-7 blocks its growth process. The transfectants show a redistribution of SIAH-1 protein within the nucleus, more specifically to the nuclear matrix, associated to dramatic changes in cell morphology and defective mitosis. Multinucleated giant cells (2-12 nuclei in more than 50% cells) were a most striking observation associated with tubulin spindle disorganization and defective cytokinesis. There were also present at high frequency abortive mitotic figures, DNA bridges and persistance of intercellular bridges and midbodies, along with an increased expression of p21Waf-1. These results indicate that the mechanism of growth arrest induced by SIAH-1 in MCF-7 cells involves disorganization of the mitotic program, mainly during nuclei separation and cytokinesis.

  7. Cell Wall Composition, Biosynthesis and Remodeling during Pollen Tube Growth

    PubMed Central

    Mollet, Jean-Claude; Leroux, Christelle; Dardelle, Flavien; Lehner, Arnaud

    2013-01-01

    The pollen tube is a fast tip-growing cell carrying the two sperm cells to the ovule allowing the double fertilization process and seed setting. To succeed in this process, the spatial and temporal controls of pollen tube growth within the female organ are critical. It requires a massive cell wall deposition to promote fast pollen tube elongation and a tight control of the cell wall remodeling to modify the mechanical properties. In addition, during its journey, the pollen tube interacts with the pistil, which plays key roles in pollen tube nutrition, guidance and in the rejection of the self-incompatible pollen. This review focuses on our current knowledge in the biochemistry and localization of the main cell wall polymers including pectin, hemicellulose, cellulose and callose from several pollen tube species. Moreover, based on transcriptomic data and functional genomic studies, the possible enzymes involved in the cell wall remodeling during pollen tube growth and their impact on the cell wall mechanics are also described. Finally, mutant analyses have permitted to gain insight in the function of several genes involved in the pollen tube cell wall biosynthesis and their roles in pollen tube growth are further discussed. PMID:27137369

  8. Effect of low dose rate radiation on cell growth kinetics.

    PubMed Central

    Gregg, E C; Yau, T M; Kim, S C

    1979-01-01

    Experimental determinations were made of cell number as a function of time for two strains of L5178Y mammalian cells maintained continuously in various environments of radiation. One strain possessed a shoulder in its dose response curve whereas the other did not. Neither strain showed any significant difference in growth rate for interdivision doses on the order of the median lethal dose or less delivered continuously at a low dose rate or pulsed every 4 h at a high instantaneous dose rate. It was also shown that large numbers of dead cells have little effect on growth rate and that these dead cells last as discrete entities for many days. A simple theory of growth rate in the presence of radiation is presented, and the agreement with the observations implies that there is no effect of any sublethal low dose rate radiation received in one generation on the growth rate or radiation sensitivity of the succeeding generation. Further analysis of the data also showed that for the no-shoulder cells at 37 degrees C, tritiated water had a relative biological effect close to unity for cell sterilization. PMID:262446

  9. Lymphatic endothelial cells support tumor growth in breast cancer

    PubMed Central

    Lee, Esak; Pandey, Niranjan B.; Popel, Aleksander S.

    2014-01-01

    Tumor lymphatic vessels (LV) serve as a conduit of tumor cell dissemination, due to their leaky nature and secretion of tumor-recruiting factors. Though lymphatic endothelial cells (LEC) lining the LV express distinct factors (also called lymphangiocrine factors), these factors and their roles in the tumor microenvironment are not well understood. Here we employ LEC, microvascular endothelial cells (MEC), and human umbilical vein endothelial cells (HUVEC) cultured in triple-negative MDA-MB-231 tumor-conditioned media (TCM) to determine the factors that may be secreted by various EC in the MDA-MB-231 breast tumor. These factors will serve as endothelium derived signaling molecules in the tumor microenvironment. We co-injected these EC with MDA-MB-231 breast cancer cells into animals and showed that LEC support tumor growth, HUVEC have no significant effect on tumor growth, whereas MEC suppress it. Focusing on LEC-mediated tumor growth, we discovered that TCM-treated LEC (‘tumor-educated LEC') secrete high amounts of EGF and PDGF-BB, compared to normal LEC. LEC-secreted EGF promotes tumor cell proliferation. LEC-secreted PDGF-BB induces pericyte infiltration and angiogenesis. These lymphangiocrine factors may support tumor growth in the tumor microenvironment. This study shows that LV serve a novel role in the tumor microenvironment apart from their classical role as conduits of metastasis. PMID:25068296

  10. Modification of growth of neuroblastoma cells in syngeneic mice by aldehyde-treated neuroblastoma cells.

    PubMed

    Bertolini, L; Diamond, L; Revoltella, R

    1976-06-01

    Pretreatment of syngeneic strain A mice with aldehyde-fixed neuroblastoma cells (clone NB6R) almost completely protected the mice against challenge with viable NB6R cells. In contrast, tumor growth was enhanced in mice treated with fixed cells after challenge with viable cells.

  11. Phase transitions in tumor growth: II prostate cancer cell lines

    NASA Astrophysics Data System (ADS)

    Llanos-Pérez, J. A.; Betancourt-Mar, A.; De Miguel, M. P.; Izquierdo-Kulich, E.; Royuela-García, M.; Tejera, E.; Nieto-Villar, J. M.

    2015-05-01

    We propose a mechanism for prostate cancer cell lines growth, LNCaP and PC3 based on a Gompertz dynamics. This growth exhibits a multifractal behavior and a "second order" phase transition. Finally, it was found that the cellular line PC3 exhibits a higher value of entropy production rate compared to LNCaP, which is indicative of the robustness of PC3, over to LNCaP and may be a quantitative index of metastatic potential tumors.

  12. Hydrodynamic effects on cell growth in agitated microcarrier bioreactors

    NASA Technical Reports Server (NTRS)

    Cherry, Robert S.; Papoutsakis, E. Terry

    1988-01-01

    The net growth rate of bovine embryonic kidney cells in microcarrier bioreactor is the result of a variable death rate imposed on a cell culture trying to grow at a constant intrinsic growth rate. The death rate is a function of the agitation conditions in the system, and increases at higher agitation because of increasingly energetic interactions of the cell covered microcarriers with turbulent eddies in the fluid. At very low agitation rates bead-bead bridging becomes important; the large clumps formed by bridging can interact with larger eddies than single beads, leading to a higher death rate at low agitation. The growth and death rate were correlated with a dimensionless eddy number which compares eddy forces to the buoyant force on the bead.

  13. Chromosomal aberrations in peripheral lymphocytes of train engine drivers.

    PubMed

    Nordenson, I; Mild, K H; Järventaus, H; Hirvonen, A; Sandström, M; Wilén, J; Blix, N; Norppa, H

    2001-07-01

    Studies of Swedish railway employees have indicated that railroad engine drivers have an increased cancer morbidity and incidence of chronic lymphatic leukemia. The drivers are exposed to relatively high magnetic fields (MF), ranging from a few to over a hundred microT. Although the possible genotoxic potential of MF is unclear, some earlier studies have indicated that occupational exposure to MF may increase chromosome aberrations in blood lymphocytes. Since an increased level of chromosomal aberrations has been suggested to predict elevated cancer risk, we performed a cytogenetic analysis on cultured (48 h) peripheral lymphocytes of Swedish train engine drivers. A pilot study of 18 engine drivers indicated a significant difference in the frequency of cells with chromosomal aberrations (gaps included or excluded) in comparison with seven concurrent referents (train dispatchers) and a control group of 16 office workers. The engine drivers had about four times higher frequency of cells with chromosome-type aberrations (excluding gaps) than the office workers (P < 0.01) and the dispatchers (P < 0.05). Seventy-eight percent of the engine drivers showed at least one cell per 100 with chromosome-type aberrations compared with 29% among the dispatchers and 31% among the office workers. In a follow-up study, another 30 engine drivers showed an increase (P < 0.05) in the frequency of cells with chromosome-type aberrations (gaps excluded) as compared with 30 referent policemen. Sixty percent of the engine drivers had one or more cells (per 100 cells) with chromosome-type aberrations compared with 30% among the policemen. In conclusion, the results of the two studies support the hypothesis that exposure to MF at mean intensities of 2-15 microT can induce chromosomal damage.

  14. Nordihydroguaiaretic Acid Inhibits Insulin-Like Growth Factor Signaling, Growth, and Survival in Human Neuroblastoma Cells

    PubMed Central

    Meyer, Gary E.; Chesler, Louis; Liu, Dandan; Gable, Karissa; Maddux, Betty A.; Goldenberg, David D.; Youngren, Jack F.; Goldfine, Ira D.; Weiss, William A.; Matthay, Katherine K.; Rosenthal, Stephen M.

    2010-01-01

    Neuroblastoma is a common pediatric malignancy that metastasizes to the liver, bone, and other organs. Children with metastatic disease have a less than 50% chance of survival with current treatments. Insulin-like growth factors (IGFs) stimulate neuroblastoma growth, survival, and motility, and are expressed by neuroblastoma cells and the tissues they invade. Thus, therapies that disrupt the effects of IGFs on neuroblastoma tumorigenesis may slow disease progression. We show that NVP-AEW541, a specific inhibitor of the IGF-I receptor (IGF-IR), potently inhibits neuroblastoma growth in vitro. Nordihydroguaiaretic acid (NDGA), a phenolic compound isolated from the creosote bush (Larrea divaricata), has anti-tumor properties against a number of malignancies, has been shown to inhibit the phosphorylation and activation of the IGF-IR in breast cancer cells, and is currently in Phase I trials for prostate cancer. In the present study in neuroblastoma, NDGA inhibits IGF-I-mediated activation of the IGF-IR and disrupts activation of ERK and Akt signaling pathways induced by IGF-I. NDGA inhibits growth of neuroblastoma cells and induces apoptosis at higher doses, causing IGF-I-resistant activation of caspase-3 and a large increase in the fraction of sub-G0 cells. In addition, NDGA inhibits the growth of xenografted human neuroblastoma tumors in nude mice. These results indicate that NDGA may be useful in the treatment of neuroblastoma and may function in part via disruption of IGF-IR signaling. PMID:17486636

  15. Nordihydroguaiaretic acid inhibits insulin-like growth factor signaling, growth, and survival in human neuroblastoma cells.

    PubMed

    Meyer, Gary E; Chesler, Louis; Liu, Dandan; Gable, Karissa; Maddux, Betty A; Goldenberg, David D; Youngren, Jack F; Goldfine, Ira D; Weiss, William A; Matthay, Katherine K; Rosenthal, Stephen M

    2007-12-15

    Neuroblastoma is a common pediatric malignancy that metastasizes to the liver, bone, and other organs. Children with metastatic disease have a less than 50% chance of survival with current treatments. Insulin-like growth factors (IGFs) stimulate neuroblastoma growth, survival, and motility, and are expressed by neuroblastoma cells and the tissues they invade. Thus, therapies that disrupt the effects of IGFs on neuroblastoma tumorigenesis may slow disease progression. We show that NVP-AEW541, a specific inhibitor of the IGF-I receptor (IGF-IR), potently inhibits neuroblastoma growth in vitro. Nordihydroguaiaretic acid (NDGA), a phenolic compound isolated from the creosote bush (Larrea divaricata), has anti-tumor properties against a number of malignancies, has been shown to inhibit the phosphorylation and activation of the IGF-IR in breast cancer cells, and is currently in Phase I trials for prostate cancer. In the present study in neuroblastoma, NDGA inhibits IGF-I-mediated activation of the IGF-IR and disrupts activation of ERK and Akt signaling pathways induced by IGF-I. NDGA inhibits growth of neuroblastoma cells and induces apoptosis at higher doses, causing IGF-I-resistant activation of caspase-3 and a large increase in the fraction of sub-G0 cells. In addition, NDGA inhibits the growth of xenogr