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Sample records for expression reveals oncogenic

  1. Integrated genome-wide genotyping and gene expression profiling reveals BCL11B as a putative oncogene in acute myeloid leukemia with 14q32 aberrations.

    PubMed

    Abbas, Saman; Sanders, Mathijs A; Zeilemaker, Annelieke; Geertsma-Kleinekoort, Wendy M C; Koenders, Jasper E; Kavelaars, Francois G; Abbas, Zabiollah G; Mahamoud, Souad; Chu, Isabel W T; Hoogenboezem, Remco; Peeters, Justine K; van Drunen, Ellen; van Galen, Janneke; Beverloo, H Berna; Löwenberg, Bob; Valk, Peter J M

    2014-05-01

    Acute myeloid leukemia is a neoplasm characterized by recurrent molecular aberrations traditionally demonstrated by cytogenetic analyses. We used high density genome-wide genotyping and gene expression profiling to reveal acquired cryptic abnormalities in acute myeloid leukemia. By genome-wide genotyping of 137 cases of primary acute myeloid leukemia, we disclosed a recurrent focal amplification on chromosome 14q32, which included the genes BCL11B, CCNK, C14orf177 and SETD3, in two cases. In the affected cases, the BCL11B gene showed consistently high mRNA expression, whereas the expression of the other genes was unperturbed. Fluorescence in situ hybridization on 40 cases of acute myeloid leukemia with high BCL11B mRNA expression [2.5-fold above median; 40 out of 530 cases (7.5%)] revealed 14q32 abnormalities in two additional cases. In the four BCL11B-rearranged cases the 14q32 locus was fused to different partner chromosomes. In fact, in two cases, we demonstrated that the focal 14q32 amplifications were integrated into transcriptionally active loci. The translocations involving BCL11B result in increased expression of full-length BCL11B protein. The BCL11B-rearranged acute myeloid leukemias expressed both myeloid and T-cell markers. These biphenotypic acute leukemias all carried FLT3 internal tandem duplications, a characteristic marker of acute myeloid leukemia. BCL11B mRNA expression in acute myeloid leukemia appeared to be strongly associated with expression of other T-cell-specific genes. Myeloid 32D(GCSF-R) cells ectopically expressing Bcl11b showed decreased proliferation rate and less maturation. In conclusion, by an integrated approach involving high-throughput genome-wide genotyping and gene expression profiling we identified BCL11B as a candidate oncogene in acute myeloid leukemia.

  2. Integrated genome-wide genotyping and gene expression profiling reveals BCL11B as a putative oncogene in acute myeloid leukemia with 14q32 aberrations

    PubMed Central

    Abbas, Saman; Sanders, Mathijs A.; Zeilemaker, Annelieke; Geertsma-Kleinekoort, Wendy M.C.; Koenders, Jasper E.; Kavelaars, Francois G.; Abbas, Zabiollah G.; Mahamoud, Souad; Chu, Isabel W.T.; Hoogenboezem, Remco; Peeters, Justine K.; van Drunen, Ellen; van Galen, Janneke; Beverloo, H. Berna; Löwenberg, Bob; Valk, Peter J.M.

    2014-01-01

    Acute myeloid leukemia is a neoplasm characterized by recurrent molecular aberrations traditionally demonstrated by cytogenetic analyses. We used high density genome-wide genotyping and gene expression profiling to reveal acquired cryptic abnormalities in acute myeloid leukemia. By genome-wide genotyping of 137 cases of primary acute myeloid leukemia, we disclosed a recurrent focal amplification on chromosome 14q32, which included the genes BCL11B, CCNK, C14orf177 and SETD3, in two cases. In the affected cases, the BCL11B gene showed consistently high mRNA expression, whereas the expression of the other genes was unperturbed. Fluorescence in situ hybridization on 40 cases of acute myeloid leukemia with high BCL11B mRNA expression [2.5-fold above median; 40 out of 530 cases (7.5%)] revealed 14q32 abnormalities in two additional cases. In the four BCL11B-rearranged cases the 14q32 locus was fused to different partner chromosomes. In fact, in two cases, we demonstrated that the focal 14q32 amplifications were integrated into transcriptionally active loci. The translocations involving BCL11B result in increased expression of full-length BCL11B protein. The BCL11B-rearranged acute myeloid leukemias expressed both myeloid and T-cell markers. These biphenotypic acute leukemias all carried FLT3 internal tandem duplications, a characteristic marker of acute myeloid leukemia. BCL11B mRNA expression in acute myeloid leukemia appeared to be strongly associated with expression of other T-cell-specific genes. Myeloid 32D(GCSF-R) cells ectopically expressing Bcl11b showed decreased proliferation rate and less maturation. In conclusion, by an integrated approach involving high-throughput genome-wide genotyping and gene expression profiling we identified BCL11B as a candidate oncogene in acute myeloid leukemia. PMID:24441149

  3. Expression of Cellular Oncogenes in Human Malignancies

    NASA Astrophysics Data System (ADS)

    Slamon, Dennis J.; Dekernion, Jean B.; Verma, Inder M.; Cline, Martin J.

    1984-04-01

    Cellular oncogenes have been implicated in the induction of malignant transformation in some model systems in vitro and may be related to malignancies in vivo in some vertebrate species. This article describes a study of the expression of 15 cellular oncogenes in fresh human tumors from 54 patients, representing 20 different tumor types. More than one cellular oncogene was transcriptionally active in all of the tumors examined. In 14 patients it was possible to study normal and malignant tissue from the same organ. In many of these patients, the transcriptional activity of certain oncogenes was greater in the malignant than the normal tissue. The cellular fes (feline sarcoma) oncogene, not previously known to be transcribed in mammalian tissue, was found to be active in lung and hematopoietic malignancies.

  4. Global expression profiling reveals gain-of-function onco-genic activity of a mutated thyroid hormone receptor in thyroid carcinogenesis

    PubMed Central

    Lu, Changxue; Mishra, Alok; Zhu, Yuelin J; Meltzer, Paul; Cheng, Sheue-yann

    2011-01-01

    Thyroid hormone receptors (TRs) are critical in regulating gene expression in normal physiological processes. Decreased expression and/or somatic mutations of TRs have been shown to be associated several types of human cancers including liver, breast, lung, and thyroid. To understand the molecular mechanisms by which mutated TRs promote carcinogenesis, an animal model of follicular thyroid carcinoma (FTC) (Thrbpv/pv mice) was used in the present study. The Thrbpv/pv mouse harbors a knockin dominant negative PV mutation, identified in a patient with resistance to thyroid hormone. To understand whether oncogenic actions of PV involve not only the loss of normal TR functions but also gain-of-function activities, we compared the gene expression profiles of thyroid lesions in Thrbpv/pv mice and Thra1-/- Thrb-/- mice that also spontaneously develop FTC, but with less severe malignancy. Analysis of the cDNA microarray data derived from microdissected thyroid tumor cells of these two mice showed contrasting global gene expression profiles. With stringent selection using 2.5-fold change (p<0.01) in cDNA microarray analysis, 241 genes with altered gene expression were identified. Nearly half of the genes (n=103: 42.7% of total) with altered gene expression in thyroid tumor cells of Thrbpv/pv mice were associated with tumorigenesis and metastasis; some of these genes function as oncogenes in human thyroid cancers. The remaining genes were found to function in transcriptional regulation, RNA processing, cell proliferation, apoptosis, angiogenesis, and cytoskeleton modification. These results indicate that the more aggressive thyroid tumor progression in Thrbpv/pv mice was not due simply to the loss of tumor suppressor functions of TR via mutation but also, importantly, to gain-of-function in the oncogenic activities of PV to drive thyroid carcinogenesis. Thus, the present study identifies a novel mechanism by which a mutated TRβ evolves with an oncogenic advantage to promote

  5. Dynamic regulation of c-Myc proto-oncogene expression during lymphocyte development revealed by a GFP-c-Myc knock-in mouse.

    PubMed

    Huang, Ching-Yu; Bredemeyer, Andrea L; Walker, Laura M; Bassing, Craig H; Sleckman, Barry P

    2008-02-01

    c-Myc induces widely varying cellular effects, including cell proliferation and cell death. These different cellular effects are determined, in part, by c-Myc protein expression levels, which are regulated through several transcriptional and post-transcriptional pathways. c-Myc transcripts can be detected in cells at all stages of B and T lymphocyte development. However, little is known about c-Myc protein expression, and how it varies, in developing lymphocytes. Here mice have been generated in which the endogenous c-Myc locus has been modified (c-Myc(G)) so that it encodes a GFP-c-Myc fusion protein. c-Myc(G/G) mice are viable, appear normal and exhibit grossly normal lymphocyte development. Flow cytometric analyses revealed significant heterogeneity in c-Myc protein expression levels in developing c-Myc(G/G) B and T lymphocytes. GFP-c-Myc expression levels were highest in proliferating lymphocytes, suggesting that c-Myc up-regulation is important for promoting lymphocyte cell division, and demonstrating that GFP-c-Myc expression is a marker of proliferating lymphocytes in vivo.

  6. Expression of hpttg proto-oncogene in lymphoid neoplasias.

    PubMed

    Sáez, Carmen; Pereda, Teresa; Borrero, Juan J; Espina, Agueda; Romero, Francisco; Tortolero, María; Pintor-Toro, José A; Segura, Dolores I; Japón, Miguel A

    2002-11-21

    Pituitary tumor-transforming gene (pttg) is a distinct proto-oncogene which is expressed in certain normal tissues with high proliferation rate and in a variety of tumors. PTTG is the vertebrate analog of yeast securins Pds1 and Cut2 with a key role in the regulation of sister chromatid separation during mitosis. Impairment of PTTG regulated functions is expected to lead to chromosomal instability and aneuploidy. Human pttg (hpttg) is abundantly expressed in Jurkat T lymphoblastic lymphoma cells but not in normal peripheral blood leukocytes. To obtain additional data on the potential role of hpttg in lymphomagenesis we selected 150 cases of lymphoid tumors for the assessment of hpttg expression in tumor tissues. Immunohistochemical studies on formalin-fixed, paraffin-embedded tissues revealed hPTTG in 38.8% of B-cell lymphomas, 70.2% of T-cell lymphomas, and 73.1% of Hodgkin's lymphomas. Among B-cell lymphomas, the most frequently immunostained tumors were plasma cell tumors, diffuse large cell lymphomas, and follicle center cell lymphomas. In Hodgkin's disease, immunoreactivity was mainly noted in Reed-Sternberg cells. In conclusion, the frequent overexpression of hpttg in many histological subtypes of lymphoma suggests the involvement of this proto-oncogene in lymphomagenesis.

  7. Developmental-stage-dependent transcriptional response to leukaemic oncogene expression

    PubMed Central

    Regha, Kakkad; Assi, Salam A.; Tsoulaki, Olga; Gilmour, Jane; Lacaud, Georges; Bonifer, Constanze

    2015-01-01

    Acute myeloid leukaemia (AML) is characterized by a block in myeloid differentiation the stage of which is dependent on the nature of the transforming oncogene and the developmental stage of the oncogenic hit. This is also true for the t(8;21) translocation that gives rise to the RUNX1-ETO fusion protein and initiates the most common form of human AML. Here we study the differentiation of mouse embryonic stem cells expressing an inducible RUNX1-ETO gene into blood cells as a model, combined with genome-wide analyses of transcription factor binding and gene expression. RUNX1-ETO interferes with both the activating and repressive function of its normal counterpart, RUNX1, at early and late stages of blood cell development. However, the response of the transcriptional network to RUNX1-ETO expression is developmental stage specific, highlighting the molecular mechanisms determining specific target cell expansion after an oncogenic hit. PMID:26018585

  8. Microarray-based gene expression profiling reveals genes and pathways involved in the oncogenic function of REG3A on pancreatic cancer cells.

    PubMed

    Xu, Qianqian; Fu, Rong; Yin, Guoxiao; Liu, Xiulan; Liu, Yang; Xiang, Ming

    2016-03-10

    We previously reported that regenerating islet-derived protein 3 alpha (REG3A) exacerbates pancreatic malignancies. The mechanism of this effect has not been clearly elucidated. Here we first identified key differentially expressed genes (DEGs) and signal pathways in the pancreatic cancer cell line SW1990, compared to two control cell lines, by microarray analysis. We then identified key genes and pathways regulated by REG3A or the cytokine IL6 in SW1990 cells. Afterwards, these DEGs induced by REG3A or IL6 were subjected to KEGG pathway enrichment analysis and GO function analysis by the DAVID online tool. Ultimately, we constructed protein-protein interaction networks among the DEGs by Cytoscape. Among the three pancreatic cell lines, SW1990 exhibited highly deterioration with the activation of genes and pathways related to proliferation, survival, angiogenesis, and invasion. As a result, 50 DEGs enriched in 11 pathways were identified in REG3A-treated SW1990 cells, and 28 DEGs enriched in 9 pathways were detected in IL6-treated cells. Overall, results of microarray analysis followed by qRT-PCR and Western blotting suggest that REG3A regulates pancreatic cell growth by increasing the expression of at least 8 genes: JAK1, STAT3, IL10, FOXM1, KRAS, MYC, CyclinD1, and c-fos; and activation of at least 4 signal pathways: TGFβ, PDGF, angiogenesis and RAS. Similar results were obtained with IL6 treatment. Regulation network analysis confirmed the cell growth related DEGs, and further uncovered three transcription factor families with immune functions regulated by REG3A.

  9. Proteogenomic analysis reveals exosomes are more oncogenic than ectosomes

    PubMed Central

    Liem, Michael; Fonseka, Pamali; Atukorala, Ishara; Ozcitti, Cemil; Mechler, Adam; Adda, Christopher G.; Ang, Ching-Seng; Mathivanan, Suresh

    2015-01-01

    Extracellular vesicles (EVs) include the exosomes (30-100 nm) that are produced through the endocytic pathway via the multivesicular bodies and the ectosomes (100-1000 nm) that are released through the budding of the plasma membrane. Despite the differences in the mode of biogenesis and size, reliable markers that can distinguish between exosomes and ectosomes are non-existent. Moreover, the precise functional differences between exosomes and ectosomes remains poorly characterised. Here, using label-free quantitative proteomics, we highlight proteins that could be exploited as markers to discriminate between exosomes and ectosomes. For the first time, a global proteogenomics analysis unveiled the secretion of mutant proteins that are implicated in cancer progression through tumor-derived EVs. Follow up integrated bioinformatics analysis highlighted the enrichment of oncogenic cargo in exosomes and ectosomes. Interestingly, exosomes induced significant cell proliferation and migration in recipient cells compared to ectosomes confirming the oncogenic nature of exosomes. These findings ascertain that cancer cells facilitate oncogenesis by the secretion of mutant and oncoproteins into the tumor microenvironment via exosomes and ectosomes. The integrative proteogenomics approach utilized in this study has the potential to identify disease biomarker candidates which can be later assayed in liquid biopsies obtained from cancer patients. PMID:25944692

  10. Proteogenomic analysis reveals exosomes are more oncogenic than ectosomes.

    PubMed

    Keerthikumar, Shivakumar; Gangoda, Lahiru; Liem, Michael; Fonseka, Pamali; Atukorala, Ishara; Ozcitti, Cemil; Mechler, Adam; Adda, Christopher G; Ang, Ching-Seng; Mathivanan, Suresh

    2015-06-20

    Extracellular vesicles (EVs) include the exosomes (30-100 nm) that are produced through the endocytic pathway via the multivesicular bodies and the ectosomes (100-1000 nm) that are released through the budding of the plasma membrane. Despite the differences in the mode of biogenesis and size, reliable markers that can distinguish between exosomes and ectosomes are non-existent. Moreover, the precise functional differences between exosomes and ectosomes remains poorly characterised. Here, using label-free quantitative proteomics, we highlight proteins that could be exploited as markers to discriminate between exosomes and ectosomes. For the first time, a global proteogenomics analysis unveiled the secretion of mutant proteins that are implicated in cancer progression through tumor-derived EVs. Follow up integrated bioinformatics analysis highlighted the enrichment of oncogenic cargo in exosomes and ectosomes. Interestingly, exosomes induced significant cell proliferation and migration in recipient cells compared to ectosomes confirming the oncogenic nature of exosomes. These findings ascertain that cancer cells facilitate oncogenesis by the secretion of mutant and oncoproteins into the tumor microenvironment via exosomes and ectosomes. The integrative proteogenomics approach utilized in this study has the potential to identify disease biomarker candidates which can be later assayed in liquid biopsies obtained from cancer patients.

  11. Pervasive transcription read-through promotes aberrant expression of oncogenes and RNA chimeras in renal carcinoma

    PubMed Central

    Grosso, Ana R; Leite, Ana P; Carvalho, Sílvia; Matos, Mafalda R; Martins, Filipa B; Vítor, Alexandra C; Desterro, Joana MP; Carmo-Fonseca, Maria; de Almeida, Sérgio F

    2015-01-01

    Aberrant expression of cancer genes and non-canonical RNA species is a hallmark of cancer. However, the mechanisms driving such atypical gene expression programs are incompletely understood. Here, our transcriptional profiling of a cohort of 50 primary clear cell renal cell carcinoma (ccRCC) samples from The Cancer Genome Atlas (TCGA) reveals that transcription read-through beyond the termination site is a source of transcriptome diversity in cancer cells. Amongst the genes most frequently mutated in ccRCC, we identified SETD2 inactivation as a potent enhancer of transcription read-through. We further show that invasion of neighbouring genes and generation of RNA chimeras are functional outcomes of transcription read-through. We identified the BCL2 oncogene as one of such invaded genes and detected a novel chimera, the CTSC-RAB38, in 20% of ccRCC samples. Collectively, our data highlight a novel link between transcription read-through and aberrant expression of oncogenes and chimeric transcripts that is prevalent in cancer. DOI: http://dx.doi.org/10.7554/eLife.09214.001 PMID:26575290

  12. ENL links histone acetylation to oncogenic gene expression in acute myeloid leukaemia.

    PubMed

    Wan, Liling; Wen, Hong; Li, Yuanyuan; Lyu, Jie; Xi, Yuanxin; Hoshii, Takayuki; Joseph, Julia K; Wang, Xiaolu; Loh, Yong-Hwee E; Erb, Michael A; Souza, Amanda L; Bradner, James E; Shen, Li; Li, Wei; Li, Haitao; Allis, C David; Armstrong, Scott A; Shi, Xiaobing

    2017-03-09

    Cancer cells are characterized by aberrant epigenetic landscapes and often exploit chromatin machinery to activate oncogenic gene expression programs. Recognition of modified histones by 'reader' proteins constitutes a key mechanism underlying these processes; therefore, targeting such pathways holds clinical promise, as exemplified by the development of bromodomain and extra-terminal (BET) inhibitors. We recently identified the YEATS domain as an acetyl-lysine-binding module, but its functional importance in human cancer remains unknown. Here we show that the YEATS domain-containing protein ENL, but not its paralogue AF9, is required for disease maintenance in acute myeloid leukaemia. CRISPR-Cas9-mediated depletion of ENL led to anti-leukaemic effects, including increased terminal myeloid differentiation and suppression of leukaemia growth in vitro and in vivo. Biochemical and crystal structural studies and chromatin-immunoprecipitation followed by sequencing analyses revealed that ENL binds to acetylated histone H3, and co-localizes with H3K27ac and H3K9ac on the promoters of actively transcribed genes that are essential for leukaemia. Disrupting the interaction between the YEATS domain and histone acetylation via structure-based mutagenesis reduced the recruitment of RNA polymerase II to ENL-target genes, leading to the suppression of oncogenic gene expression programs. Notably, disrupting the functionality of ENL further sensitized leukaemia cells to BET inhibitors. Together, our data identify ENL as a histone acetylation reader that regulates oncogenic transcriptional programs in acute myeloid leukaemia, and suggest that displacement of ENL from chromatin may be a promising epigenetic therapy, alone or in combination with BET inhibitors, for aggressive leukaemia.

  13. Development of a highly efficient expression cDNA cloning system: application to oncogene isolation.

    PubMed Central

    Miki, T; Fleming, T P; Crescenzi, M; Molloy, C J; Blam, S B; Reynolds, S H; Aaronson, S A

    1991-01-01

    We developed an expression cDNA cloning system capable of generating high-complexity libraries with unidirectionally inserted cDNA fragments and allowing efficient plasmid rescue. As an application of this system, a cDNA library was constructed from an NIH 3T3 transformant induced by mouse hepatocellular carcinoma DNA. Transfection of NIH 3T3 cells by the library DNA led to the detection of several transformed foci from which identical plasmids with transforming ability could be rescued. Structure and sequence analysis of the cDNA clones revealed that the oncogene was created by recombinational events involving an unknown gene and the mouse homologue of the B-raf protooncogene. Detection of the same genetic rearrangement in independent primary transformants implied that generation of the oncogene occurred within the tumor rather than during DNA transfection or cDNA library construction. The high frequency at which clones were identified and the large sizes of some of the transforming cDNA inserts isolated suggest wide applicability of this mammalian expression cloning system for isolating cDNAs of biologic interest. Images PMID:2052597

  14. Clinical correlates in acromegalic patients with pituitary tumors expressing GSP oncogenes.

    PubMed

    Buchfelder, M; Fahlbusch, R; Merz, T; Symowski, H; Adams, E F

    1999-05-01

    We herein review published findings on the clinical characteristics of acromegalic patients harboring pituitary somatotrophinomas expressing adenylyl cyclase activating gsp mutations and present an update of our own data on a large series of 176 patients with and without these oncogenes. Gsp oncogenes are the result of point mutations in either codon 201 or 227 of the Gs-alpha subunit of the Gs-protein which controls adenylyl cyclase. They result ultimately in increased intracellular cAMP levels and thus in excessive growth hormone (GH) secretion. Our large series has allowed us to characterise patients with mutations in codon 201 and the far rarer group possessing codon 227 defects. Both groups were compared with patients without gsp oncogenes. In accordance with previous findings, there was no statistically significant difference in age of the patients belonging to each group, the overall average tumor diameter nor in pre-operative serum GH levels, although the latter showed a tendency to be lower in patients with gsp oncogenes. The distribution of different types of response during an oral glucose tolerance test (no change, paradoxical rise or greater than 50% decrease in serum GH levels) did not differ between the 3 groups. However, the incidence of microadenomas was higher in acromegalics expressing gsp oncogenes in patients possessing mutations in codon 227. Additionally, the incidence of invasiveness was much lower (10% v. 33%) in those tumors with mutations in codon 227. Finally, previous in-vitro data indicating that gsp oncogene-expressing tumors may respond more efficiently to the somatostatin analogue, octreotide, have been confirmed by subsequent in-vivo studies showing a better reduction in serum GH levels in patients with gsp oncogenes. These latter findings suggest that presence of gsp oncogenes may be a marker for good reponsiveness to octreotide. Assessment of gsp oncogene status of surgically removed pituitary somatotrophinomas may thus be

  15. Derepression of hTERT gene expression promotes escape from oncogene-induced cellular senescence

    PubMed Central

    Patel, Priyanka L.; Suram, Anitha; Mirani, Neena; Bischof, Oliver; Herbig, Utz

    2016-01-01

    Oncogene-induced senescence (OIS) is a critical tumor-suppressing mechanism that restrains cancer progression at premalignant stages, in part by causing telomere dysfunction. Currently it is unknown whether this proliferative arrest presents a stable and therefore irreversible barrier to cancer progression. Here we demonstrate that cells frequently escape OIS induced by oncogenic H-Ras and B-Raf, after a prolonged period in the senescence arrested state. Cells that had escaped senescence displayed high oncogene expression levels, retained functional DNA damage responses, and acquired chromatin changes that promoted c-Myc–dependent expression of the human telomerase reverse transcriptase gene (hTERT). Telomerase was able to resolve existing telomeric DNA damage response foci and suppressed formation of new ones that were generated as a consequence of DNA replication stress and oncogenic signals. Inhibition of MAP kinase signaling, suppressing c-Myc expression, or inhibiting telomerase activity, caused telomere dysfunction and proliferative defects in cells that had escaped senescence, whereas ectopic expression of hTERT facilitated OIS escape. In human early neoplastic skin and breast tissue, hTERT expression was detected in cells that displayed features of senescence, suggesting that reactivation of telomerase expression in senescent cells is an early event during cancer progression in humans. Together, our data demonstrate that cells arrested in OIS retain the potential to escape senescence by mechanisms that involve derepression of hTERT expression. PMID:27503890

  16. Cancer induction by restriction of oncogene expression to the stem cell compartment

    PubMed Central

    Pérez-Caro, María; Cobaleda, César; González-Herrero, Inés; Vicente-Dueñas, Carolina; Bermejo-Rodríguez, Camino; Sánchez-Beato, Margarita; Orfao, Alberto; Pintado, Belén; Flores, Teresa; Sánchez-Martín, Manuel; Jiménez, Rafael; Piris, Miguel A; Sánchez-García, Isidro

    2009-01-01

    In human cancers, all cancerous cells carry the oncogenic genetic lesions. However, to elucidate whether cancer is a stem cell-driven tissue, we have developed a strategy to limit oncogene expression to the stem cell compartment in a transgenic mouse setting. Here, we focus on the effects of the BCR-ABLp210 oncogene, associated with chronic myeloid leukaemia (CML) in humans. We show that CML phenotype and biology can be established in mice by restricting BCR-ABLp210 expression to stem cell antigen 1 (Sca1)+ cells. The course of the disease in Sca1-BCR-ABLp210 mice was not modified on STI571 treatment. However, BCR-ABLp210-induced CML is reversible through the unique elimination of the cancer stem cells (CSCs). Overall, our data show that oncogene expression in Sca1+ cells is all that is required to fully reprogramme it, giving rise to a full-blown, oncogene-specified tumour with all its mature cellular diversity, and that elimination of the CSCs is enough to eradicate the whole tumour. PMID:19037256

  17. C-myc oncogene expression in human melanoma and its relationship with tumour antigenicity.

    PubMed

    Grover, R; Ross, D A; Richman, P I; Robinson, B; Wilson, G D

    1996-08-01

    Melanoma produces specific tumour antigens which are capable of eliciting an immune response. However, this tumour evades the immune system, in part, by downregulation of class I HLA antigens on the cell surface, which are required for T cell recognition. It has been suggested that the oncogene c-myc may have a role in effecting this change in vitro, however, the relationship between oncoprotein level and tumour antigenicity has not been established in human tumours. This study measured c-myc oncoprotein in 94 melanoma specimens (46 primary tumours and 48 regional metastases) using flow cytometry and evaluated class I HLA expression with immunohistochemistry. C-myc expression was found in 91 tumours (96%) with higher expression in metastases than primary melanomas (P<0.005). Class I HLA expression was found to show great variation although metastases showed less antigenicity than primary tumours (P<0.01). Analysis of the relationship between these two parameters revealed a highly significant correlation in both primary (P<0.01) and metastatic disease (P<0.01), with high oncoprotein being associated with down regulation of cell surface antigens. Knowledge of the control of tumour antigenicity is likely to provide an objective platform for the development of new strategies for immunotherapy.

  18. Somatic Copy Number Alterations at Oncogenic Loci Show Diverse Correlations with Gene Expression

    NASA Astrophysics Data System (ADS)

    Roszik, Jason; Wu, Chang-Jiun; Siroy, Alan E.; Lazar, Alexander J.; Davies, Michael A.; Woodman, Scott E.; Kwong, Lawrence N.

    2016-01-01

    Somatic copy number alterations (SCNAs) affecting oncogenic drivers have a firmly established role in promoting cancer. However, no agreed-upon standard exists for calling locus-specific amplifications and deletions in each patient sample. Here, we report the correlative analysis of copy number amplitude and length with gene expression across 6,109 samples from The Cancer Genome Atlas (TCGA) dataset across 16 cancer types. Using specificity, sensitivity, and precision-based scores, we assigned optimized amplitude and length cutoffs for nine recurrent SCNAs affecting known oncogenic drivers, using mRNA expression as a functional readout. These cutoffs captured the majority of SCNA-driven, highly-expression-altered samples. The majority of oncogenes required only amplitude cutoffs, as high amplitude samples were almost invariably focal; however, CDKN2A and PTEN uniquely required both amplitude and length cutoffs as primary predictors. For PTEN, these extended to downstream AKT activation. In contrast, SCNA genes located peri-telomerically or in fragile sites showed poor expression-copy number correlations. Overall, our analyses identify optimized amplitude and length cutoffs as efficient predictors of gene expression changes for specific oncogenic SCNAs, yet warn against one-size-fits-all interpretations across all loci. Our results have implications for cancer data analyses and the clinic, where copy number and mutation data are increasingly used to personalize cancer therapy.

  19. Somatic Copy Number Alterations at Oncogenic Loci Show Diverse Correlations with Gene Expression

    PubMed Central

    Roszik, Jason; Wu, Chang-Jiun; Siroy, Alan E.; Lazar, Alexander J.; Davies, Michael A; Woodman, Scott E; Kwong, Lawrence N

    2016-01-01

    Somatic copy number alterations (SCNAs) affecting oncogenic drivers have a firmly established role in promoting cancer. However, no agreed-upon standard exists for calling locus-specific amplifications and deletions in each patient sample. Here, we report the correlative analysis of copy number amplitude and length with gene expression across 6,109 samples from The Cancer Genome Atlas (TCGA) dataset across 16 cancer types. Using specificity, sensitivity, and precision-based scores, we assigned optimized amplitude and length cutoffs for nine recurrent SCNAs affecting known oncogenic drivers, using mRNA expression as a functional readout. These cutoffs captured the majority of SCNA-driven, highly-expression-altered samples. The majority of oncogenes required only amplitude cutoffs, as high amplitude samples were almost invariably focal; however, CDKN2A and PTEN uniquely required both amplitude and length cutoffs as primary predictors. For PTEN, these extended to downstream AKT activation. In contrast, SCNA genes located peri-telomerically or in fragile sites showed poor expression-copy number correlations. Overall, our analyses identify optimized amplitude and length cutoffs as efficient predictors of gene expression changes for specific oncogenic SCNAs, yet warn against one-size-fits-all interpretations across all loci. Our results have implications for cancer data analyses and the clinic, where copy number and mutation data are increasingly used to personalize cancer therapy. PMID:26787600

  20. Reduced expression of AMPK-β1 during tumor progression enhances the oncogenic capacity of advanced ovarian cancer

    PubMed Central

    2014-01-01

    AMP-activated protein kinase (AMPK) is a key energy sensor that is involved in regulating cell metabolism. Our previous study revealed that the subunits of the heterotimeric AMPK enzyme are diversely expressed during ovarian cancer progression. However, the impact of the variable expression of these AMPK subunits in ovarian cancer oncogenesis remains obscure. Here, we provide evidence to show that reduced expression of the AMPK-β1 subunit during tumor progression is associated with the increased oncogenic capacity of advanced ovarian cancer cells. Immunohistochemical analysis revealed that AMPK-β1 levels were reduced in advanced-stage (P = 0.008), high-grade (P = 0.013) and metastatic ovarian cancers (P = 0.008). Intriguingly, down-regulation of AMPK-β1 was progressively reduced from tumor stages 1 to 3 of ovarian cancer. Functionally, enforced expression of AMPK-β1 inhibited ovarian-cancer-cell proliferation, anchorage-independent cell growth, cell migration and invasion. Conversely, depletion of AMPK-β1 by siRNA enhanced the oncogenic capacities of ovarian cancer cells, suggesting that the loss of AMPK-β1 favors the aggressiveness of ovarian cancer. Mechanistically, enforced expression of AMPK-β1 increased AMPK activity, which, in turn, induced cell-cycle arrest via inhibition of AKT/ERK signaling activity as well as impaired cell migration/invasion through the suppression of JNK signaling in ovarian cancer cells. Taken together, these findings suggest that the reduced expression of AMPK-β1 confers lower AMPK activity, which enhances the oncogenic capacity of advanced-stage ovarian cancer. PMID:24602453

  1. Cloning and characterization of the murine homolog of the sno proto-oncogene reveals a novel splice variant

    NASA Technical Reports Server (NTRS)

    Pelzer, T.; Lyons, G. E.; Kim, S.; Moreadith, R. W.; Blomqvist, C. G. (Principal Investigator)

    1996-01-01

    The cellular function(s) of the SNO protein remain undefined. To gain a better understanding of possible developmental roles of this cellular proto-oncogene, we have cloned two murine sno cDNAs and have investigated their expression patterns in embryonic and postnatal tissues. A single major transcript of 7.5 kb is detected in multiple tissues by Northern blot. However, reverse transcriptase polymerase chain reaction (RT-PCR) and RNAse protection assays revealed a novel splice variant in every tissue examined. Two isoforms, termed sno N and sno-dE3 (dE3, deletion within exon 3), were identified. The sno-dE3 isoform employs a novel 5' splice site located within the coding region of the third exon and deletes potential kinase recognition motifs. Transcripts of both sno isoforms accumulate ubiquitously but are most abundant in the developing central nervous system. The in situ hybridization patterns of sno expression during murine development suggest potential roles in tissues with a high degree of cellular proliferation. Expression in terminally differentiated tissues such as muscle and neurons indicates that SNO may have multiple functional activities.

  2. ChIP-on-chip significance analysis reveals large-scale binding and regulation by human transcription factor oncogenes

    PubMed Central

    Margolin, Adam A.; Palomero, Teresa; Sumazin, Pavel; Califano, Andrea; Ferrando, Adolfo A.; Stolovitzky, Gustavo

    2009-01-01

    ChIP-on-chip has emerged as a powerful tool to dissect the complex network of regulatory interactions between transcription factors and their targets. However, most ChIP-on-chip analysis methods use conservative approaches aimed at minimizing false-positive transcription factor targets. We present a model with improved sensitivity in detecting binding events from ChIP-on-chip data. Its application to human T cells, followed by extensive biochemical validation, reveals that 3 oncogenic transcription factors, NOTCH1, MYC, and HES1, bind to several thousand target gene promoters, up to an order of magnitude increase over conventional analysis methods. Gene expression profiling upon NOTCH1 inhibition shows broad-scale functional regulation across the entire range of predicted target genes, establishing a closer link between occupancy and regulation. Finally, the increased sensitivity reveals a combinatorial regulatory program in which MYC cobinds to virtually all NOTCH1-bound promoters. Overall, these results suggest an unappreciated complexity of transcriptional regulatory networks and highlight the fundamental importance of genome-scale analysis to represent transcriptional programs. PMID:19118200

  3. ChIP-on-chip significance analysis reveals large-scale binding and regulation by human transcription factor oncogenes.

    PubMed

    Margolin, Adam A; Palomero, Teresa; Sumazin, Pavel; Califano, Andrea; Ferrando, Adolfo A; Stolovitzky, Gustavo

    2009-01-06

    ChIP-on-chip has emerged as a powerful tool to dissect the complex network of regulatory interactions between transcription factors and their targets. However, most ChIP-on-chip analysis methods use conservative approaches aimed at minimizing false-positive transcription factor targets. We present a model with improved sensitivity in detecting binding events from ChIP-on-chip data. Its application to human T cells, followed by extensive biochemical validation, reveals that 3 oncogenic transcription factors, NOTCH1, MYC, and HES1, bind to several thousand target gene promoters, up to an order of magnitude increase over conventional analysis methods. Gene expression profiling upon NOTCH1 inhibition shows broad-scale functional regulation across the entire range of predicted target genes, establishing a closer link between occupancy and regulation. Finally, the increased sensitivity reveals a combinatorial regulatory program in which MYC cobinds to virtually all NOTCH1-bound promoters. Overall, these results suggest an unappreciated complexity of transcriptional regulatory networks and highlight the fundamental importance of genome-scale analysis to represent transcriptional programs.

  4. Gene Essentiality Profiling Reveals Gene Networks and Synthetic Lethal Interactions with Oncogenic Ras.

    PubMed

    Wang, Tim; Yu, Haiyan; Hughes, Nicholas W; Liu, Bingxu; Kendirli, Arek; Klein, Klara; Chen, Walter W; Lander, Eric S; Sabatini, David M

    2017-02-23

    The genetic dependencies of human cancers widely vary. Here, we catalog this heterogeneity and use it to identify functional gene interactions and genotype-dependent liabilities in cancer. By using genome-wide CRISPR-based screens, we generate a gene essentiality dataset across 14 human acute myeloid leukemia (AML) cell lines. Sets of genes with correlated patterns of essentiality across the lines reveal new gene relationships, the essential substrates of enzymes, and the molecular functions of uncharacterized proteins. Comparisons of differentially essential genes between Ras-dependent and -independent lines uncover synthetic lethal partners of oncogenic Ras. Screens in both human AML and engineered mouse pro-B cells converge on a surprisingly small number of genes in the Ras processing and MAPK pathways and pinpoint PREX1 as an AML-specific activator of MAPK signaling. Our findings suggest general strategies for defining mammalian gene networks and synthetic lethal interactions by exploiting the natural genetic and epigenetic diversity of human cancer cells.

  5. Cellular oncogene expression following exposure of mice to {gamma}-rays

    SciTech Connect

    Anderson, A.; Woloschak, G.E.

    1991-06-12

    We examined the effects of total body exposure of BCF1 mice to {gamma}-rays (300 cGy) in modulating expression of cellular oncogenes in both gut and liver tissues. We selected specific cellular oncogenes (c-fos, c-myc, c-src, and c-H-ras), based on their normal expression in liver and gut tissues from untreated mice. As early as 5 min. following whole body exposure of BCF1 mice to {gamma}-rays we detected induction of mRNA specific for c-src and c-H-ras in both liver and gut tissues. c-fos RNA was slightly decreased in accumulation in gut but was unaffected in liver tissue from irradiated mice relative to untreated controls. c-myc mRNA accumulation was unaffected in all tissues examined. These experiments document that modulation of cellular oncogene expression can occur as an early event in tissues following irradiation and suggest that this modulation may play a role in radiation-induced carcinogenesis.

  6. DEK Proto-Oncogene Expression Interferes with the Normal Epithelial Differentiation Program

    PubMed Central

    Wise-Draper, Trisha M.; Morreale, Richard J.; Morris, Teresa A.; Mintz-Cole, Rachael A.; Hoskins, Elizabeth E.; Balsitis, Scott J.; Husseinzadeh, Nader; Witte, David P.; Wikenheiser-Brokamp, Kathryn A.; Lambert, Paul F.; Wells, Susanne I.

    2009-01-01

    Overexpression of the DEK gene is associated with multiple human cancers, but its specific roles as a putative oncogene are not well defined. DEK transcription was previously shown to be induced by the high-risk human papillomavirus (HPV) E7 oncogene via E2F and Rb pathways. Transient DEK overexpression was able to inhibit both senescence and apoptosis in cultured cells. In at least the latter case, this mechanism involved the destabilization of p53 and the decreased expression of p53 target genes. We show here that DEK overexpression disrupts the normal differentiation program in a manner that is independent of either p53 or cell death. DEK expression was distinctly repressed upon the differentiation of cultured primary human keratinocytes, and stable DEK overexpression caused epidermal thickening in an organotypic raft model system. The observed hyperplasia involved a delay in keratinocyte differentiation toward a more undifferentiated state, and expansion of the basal cell compartment was due to increased proliferation, but not apoptosis. These phenotypes were accompanied by elevated p63 expression in the absence of p53 destabilization. In further support of bona fide oncogenic DEK activities, we report here up-regulated DEK protein levels in both human papilloma virus-positive hyperplastic murine skin and a subset of human squamous cell carcinomas. We suggest that DEK up-regulation may contribute to carcinoma development at least in part through increased proliferation and retardation of differentiation. PMID:19036808

  7. Senescence-Associated Secretory Phenotypes Reveal Cell-Nonautonomous Functions of Oncogenic RAS and the p53 Tumor Suppressor

    SciTech Connect

    Coppé, Jean-Philippe; Patil, Christopher; Rodier, Francis; Sun, Yu; Munoz, Denise; Goldstein, Joshua; Nelson, Peter; Desprez, Pierre-Yves; Campisi, Judith

    2008-10-24

    Cellular senescence suppresses cancer by arresting cell proliferation, essentially permanently, in response to oncogenic stimuli, including genotoxic stress. We modified the use of antibody arrays to provide a quantitative assessment of factors secreted by senescent cells. We show that human cells induced to senesce by genotoxic stress secrete myriad factors associated with inflammation and malignancy. This senescence-associated secretory phenotype (SASP) developed slowly over several days and only after DNA damage of sufficient magnitude to induce senescence. Remarkably similar SASPs developed in normal fibroblasts, normal epithelial cells, and epithelial tumor cells after genotoxic stress in culture, and in epithelial tumor cells in vivo after treatment of prostate cancer patients with DNA-damaging chemotherapy. In cultured premalignant epithelial cells, SASPs induced an epithelial-mesenchyme transition and invasiveness, hallmarks of malignancy, by a paracrine mechanism that depended largely on the SASP factors interleukin (IL)-6 and IL-8. Strikingly, two manipulations markedly amplified, and accelerated development of, the SASPs: oncogenic RAS expression, which causes genotoxic stress and senescence in normal cells, and functional loss of the p53 tumor suppressor protein. Both loss of p53 and gain of oncogenic RAS also exacerbated the promalignant paracrine activities of the SASPs. Our findings define a central feature of genotoxic stress-induced senescence. Moreover, they suggest a cell-nonautonomous mechanism by which p53 can restrain, and oncogenic RAS can promote, the development of age-related cancer by altering the tissue microenvironment.

  8. Senescence-Associated Secretory Phenotypes Reveal Cell-Nonautonomous Functions of Oncogenic RAS and the p53 Tumor Suppressor

    PubMed Central

    Coppé, Jean-Philippe; Sun, Yu; Muñoz, Denise P; Goldstein, Joshua; Nelson, Peter S; Desprez, Pierre-Yves; Campisi, Judith

    2008-01-01

    Cellular senescence suppresses cancer by arresting cell proliferation, essentially permanently, in response to oncogenic stimuli, including genotoxic stress. We modified the use of antibody arrays to provide a quantitative assessment of factors secreted by senescent cells. We show that human cells induced to senesce by genotoxic stress secrete myriad factors associated with inflammation and malignancy. This senescence-associated secretory phenotype (SASP) developed slowly over several days and only after DNA damage of sufficient magnitude to induce senescence. Remarkably similar SASPs developed in normal fibroblasts, normal epithelial cells, and epithelial tumor cells after genotoxic stress in culture, and in epithelial tumor cells in vivo after treatment of prostate cancer patients with DNA-damaging chemotherapy. In cultured premalignant epithelial cells, SASPs induced an epithelial–mesenchyme transition and invasiveness, hallmarks of malignancy, by a paracrine mechanism that depended largely on the SASP factors interleukin (IL)-6 and IL-8. Strikingly, two manipulations markedly amplified, and accelerated development of, the SASPs: oncogenic RAS expression, which causes genotoxic stress and senescence in normal cells, and functional loss of the p53 tumor suppressor protein. Both loss of p53 and gain of oncogenic RAS also exacerbated the promalignant paracrine activities of the SASPs. Our findings define a central feature of genotoxic stress-induced senescence. Moreover, they suggest a cell-nonautonomous mechanism by which p53 can restrain, and oncogenic RAS can promote, the development of age-related cancer by altering the tissue microenvironment. PMID:19053174

  9. Regulation of oncogene expression in T-DNA-transformed host plant cells.

    PubMed

    Zhang, Yi; Lee, Chil-Woo; Wehner, Nora; Imdahl, Fabian; Svetlana, Veselova; Weiste, Christoph; Dröge-Laser, Wolfgang; Deeken, Rosalia

    2015-01-01

    Virulent Agrobacterium tumefaciens strains integrate their T-DNA into the plant genome where the encoded agrobacterial oncogenes are expressed and cause crown gall disease. Essential for crown gall development are IaaH (indole-3-acetamide hydrolase), IaaM (tryptophan monooxygenase) and Ipt (isopentenyl transferase), which encode enzymes for the biosynthesis of auxin (IaaH, IaaM) and cytokinin (Ipt). Although these oncogenes are well studied as the tumor-inducing principle, nothing is known about the regulation of oncogene expression in plant cells. Our studies show that the intergenic regions (IGRs) between the coding sequences (CDS) of the three oncogenes function as promoters in plant cells. These promoters possess a eukaryotic sequence organization and cis-regulatory elements for the binding of plant transcription factors. WRKY18, WRKY40, WRKY60 and ARF5 were identified as activators of the Ipt promoter whereas IaaH and IaaM is constitutively expressed and no transcription factor further activates their promoters. Consistent with these results, the wrky triple mutant plants in particular, develops smaller crown galls than wild-type and exhibits a reduced Ipt transcription, despite the presence of an intact ARF5 gene. WRKY40 and WRKY60 gene expression is induced by A. tumefaciens within a few hours whereas the ARF5 gene is transcribed later during crown gall development. The WRKY proteins interact with ARF5 in the plant nucleus, but only WRKY40 together with ARF5 synergistically boosts the activation of the Ipt promoter in an auxin-dependent manner. From our data, we propose that A. tumefaciens initially induces WRKY40 gene expression as a pathogen defense response of the host cell. The WRKY protein is recruited to induce Ipt expression, which initiates cytokinin-dependent host cell division. With increasing auxin levels triggered by ubiquitous expression of IaaH and IaaM, ARF5 is activated and interacts with WRKY40 to potentiate Ipt expression and balance

  10. MicroRNA29a regulates the expression of the nuclear oncogene Ski.

    PubMed

    Teichler, Sabine; Illmer, Thomas; Roemhild, Josephine; Ovcharenko, Dmitriy; Stiewe, Thorsten; Neubauer, Andreas

    2011-08-18

    MicroRNAs (miRNAs) are small, noncoding RNA molecules that regulate growth and differentiation. miRNAs are frequently located at cancer-specific fragile sites in the human genome, such as chromosome 7q. The nuclear oncogene SKI is up-regulated in acute myeloid leukemia (AML) with -7/del7q. Here we asked whether loss of miRNAs on chromosome 7q may explain this up-regulation. miR-29a expression was found to be down-regulated in AML with -7/del7q. Forced expression of miR-29a down-regulated Ski and its target gene, Nr-CAM, whereas miR-29a inhibition induced Ski expression. Luciferase assays validated a functional binding site for miR-29a in the 3' untranslated region of SKI. Finally, in samples of AML patients, we observed an inverse correlation of Ski and miR-29a expression, respectively. In conclusion, up-regulation of Ski in AML with -7/del7q is caused by loss of miR-29a. miR-29a may therefore function as an important tumor suppressor in AML by restraining expression of the SKI oncogene.

  11. Expression of cellular oncogenes in primary cells from human acute leukemias.

    PubMed Central

    Mavilio, F; Sposi, N M; Petrini, M; Bottero, L; Marinucci, M; De Rossi, G; Amadori, S; Mandelli, F; Peschle, C

    1986-01-01

    The structure and the expression of 11 cellular oncogenes (protooncogenes) were analyzed in primary cells from 20 acute lymphocytic (ALL) and 31 acute myelogenous (AML) leukemia patients. Neoplastic cells, obtained prior to initiation of therapy, were purified and classified, on the basis of both surface antigen pattern and morphology, into pre-B, B, and T ALL and M1-M5 AML. RNA was extracted and analyzed for expression of cellular oncogenes coding for nuclear proteins (c-myc, c-myb, c-fos), the beta-chain of platelet-derived growth factor (c-sis), growth factor receptors or related proteins (c-src, c-abl, c-fes, c-erbB), or putative intermediate transducers of mitogenic signals (c-Ha-ras, c-Ki-ras, c-N-ras). Quantitative analysis of total RNA was carried out by dot blot hybridization to specific cDNA or genomic probes. Number and size of transcripts were evaluated by blot hybridization of electrophoretically fractionated poly(A)+ RNA. Expression of c-myc and c-myb was detected in all leukemic cells at variable levels and was characterized by well-defined patterns within ALL subtypes. Conversely, significant levels of c-fos transcripts were detected only in myelomonocytic (M4) and monocytic (M5) leukemias. Among the "src-family," c-fes was expressed more in AML than ALL, and c-abl was expressed at variable but not elevated levels in all leukemia types. c-Ha-ras was uniformly expressed at low levels, as in non-neoplastic cells. c-Ki-ras transcription was detected only in T ALL; N-ras expression was barely demonstrable. The structure of these protooncogenes was not grossly modified, as evaluated by Southern analysis, except for c-myc rearrangement in B ALL. These studies indicate that cellular oncogene expression in specific subtypes of leukemic cells may relate to either the proliferative activity (c-myc, c-myb) or the differentiation state (c-fos) of the cells, or possibly to expression of receptors for putative hemopoiesis-related growth factors (c-fes, c

  12. Expression of BCR-ABL1 oncogene relative to ABL1 gene changes overtime in chronic myeloid leukemia

    SciTech Connect

    Gupta, Manu; Milani, Lili; Hermansson, Monica; Simonsson, Bengt; Markevaern, Berit; Syvaenen, Ann Christine; Barbany, Gisela

    2008-02-15

    Using a quantitative single nucleotide polymorphism (SNP) assay we have investigated the changes in the expression of the BCR-ABL1 oncogene relative to the wild-type ABL1 and BCR alleles in cells from chronic myeloid leukemia (CML) patients not responding to therapy. The results show a progressive increase in the BCR-ABL1 oncogene expression at the expense of decreased expression of the ABL1 allele, not involved in the fusion. No relative changes in the expression of the two BCR alleles were found. These results demonstrate that allele-specific changes in gene expression, with selective, progressive silencing of the wild-type ABL1 allele in favor of the oncogenic BCR-ABL1 allele occur in CML patients with therapy-resistant disease.

  13. STAT5 Outcompetes STAT3 To Regulate the Expression of the Oncogenic Transcriptional Modulator BCL6

    PubMed Central

    Walker, Sarah R.; Nelson, Erik A.; Yeh, Jennifer E.; Pinello, Luca; Yuan, Guo-Cheng

    2013-01-01

    Inappropriate activation of the transcription factors STAT3 and STAT5 has been shown to drive cancer pathogenesis through dysregulation of genes involved in cell survival, growth, and differentiation. Although STAT3 and STAT5 are structurally related, they can have opposite effects on key genes, including BCL6. BCL6, a transcriptional repressor, has been shown to be oncogenic in diffuse large B cell lymphoma. BCL6 also plays an important role in breast cancer pathogenesis, a disease in which STAT3 and STAT5 can be activated individually or concomitantly. To determine the mechanism by which these oncogenic transcription factors regulate BCL6 transcription, we analyzed their effects at the levels of chromatin and gene expression. We found that STAT3 increases expression of BCL6 and enhances recruitment of RNA polymerase II phosphorylated at a site associated with transcriptional initiation. STAT5, in contrast, represses BCL6 expression below basal levels and decreases the association of RNA polymerase II at the gene. Furthermore, the repression mediated by STAT5 is dominant over STAT3-mediated induction. STAT5 exerts this effect by displacing STAT3 from one of the two regulatory regions to which it binds. These findings may underlie the divergent biology of breast cancers containing activated STAT3 alone or in conjunction with activated STAT5. PMID:23716595

  14. Tocopherol Succinate: Modulation of Antioxidant Enzymes and Oncogene Expression, and Hematopoietic Recovery

    SciTech Connect

    Singh, Vijay K.; Parekh, Vaishali I.; Brown, Darren S.; Kao, Tzu-Cheg; Mog, Steven R.

    2011-02-01

    Purpose: A class of naturally occurring isoforms of tocopherol (tocols) was shown to have varying degrees of protection when administered before radiation exposure. We recently demonstrated that {alpha}-tocopherol succinate (TS) is a potential radiation prophylactic agent. Our objective in this study was to further investigate the mechanism of action of TS in mice exposed to {sup 60}Co {gamma}-radiation. Methods and Materials: We evaluated the effects of TS on expression of antioxidant enzymes and oncogenes by quantitative RT-PCR in bone marrow cells of {sup 60}Co {gamma}-irradiated mice. Further, we tested the ability of TS to rescue and repopulate hematopoietic stem cells by analyzing bone marrow cellularity and spleen colony forming unit in spleen of TS-injected and irradiated mice. Results: Our results demonstrate that TS modulated the expression of antioxidant enzymes and inhibited expression of oncogenes in irradiated mice at different time points. TS also increased colony forming unit-spleen numbers and bone marrow cellularity in irradiated mice. Conclusions: Results provide additional support for the observed radioprotective efficacy of TS and insight into mechanisms.

  15. Investigating the Expression of Oncogenic and Tumor Suppressive MicroRNA in DLBCL.

    PubMed

    Handal, Brian; Enlow, Rossanna; Lara, Daniel; Bailey, Mark; Vega, Francisco; Hu, Peter; Lennon, Alan

    2013-01-01

    Diffuse Large B-cell Lymphoma (DLBCL) is the most common form of lymphoma, accounting for 40 percent of newly diagnosed cases each year. DLBCL is an aggressive abnormal growth of tissue characterized by the accumulation of abnormal B-lymphocytes in the lymphatics of affected individuals. The goal of this study was to analyze microRNA (miRNA) as an alternative method of diagnosis and treatment for patients affected with the observed cancer. MiRNAs are small, non-coding, endogenous RNA that control gene expression at the post-transcriptional level. Emerging evidence suggests that miRNA-mediated gene regulation has a functional role in cancer and could prove to be crucial targets for therapeutic intervention. Here, we provide a quantitative study on the expression of a diverse class of oncogenic and tumor suppressive miRNA that have shown to regulate oncoproteins involved in differentiation, proliferation, and/or apoptosis.

  16. Multiple endocrine neoplasia induced by the promiscuous expression of a viral oncogene.

    PubMed

    Reynolds, R K; Hoekzema, G S; Vogel, J; Hinrichs, S H; Jay, G

    1988-05-01

    There is increasing evidence for the importance of events that govern and influence the interaction between the transformed cell and its host being ultimately responsible for the establishment of the cancer phenotype. To derive an animal model that will allow us to define some of these phenomena at the molecular level, we have chosen to induce the expression of a viral oncogene in all tissue types, with the hope of identifying sites that are more susceptible to malignant transformation. When the gene for simian virus 40 large tumor antigen (T antigen) was placed under the control of a major histocompatibility complex class I gene enhancer, the resulting transgenic mice not only developed choroid plexus papillomas, as seen with wild-type simian virus 40, but also lymphoid hyperplasia and multiple endocrine neoplasias. The development of lymphoid hyperplasia was preceded by an elevated level of expression of T antigen in these tissues at an early age. Surprisingly, the striking thymic hyperplasia has not been observed to progress toward malignancy. The multiple endocrine neoplasias developed later in life and involved the pancreas, pituitary, thyroid, adrenals, and testes. While not preceded by an elevated level of expression of T antigen, once endocrine tumors appeared they quickly progressed toward malignant growth. Although other tissues also exhibited a basal level of expression of the viral oncogene similar to that detected in endocrine tissues, they rarely developed tumors. This transgenic mouse model seems particularly suitable for a molecular understanding of events responsible for certain tissue types being so much more susceptible to neoplastic conversion, with others being so refractory.

  17. Wild-type p53 induces diverse effects in 32D cells expressing different oncogenes.

    PubMed Central

    Soddu, S; Blandino, G; Scardigli, R; Martinelli, R; Rizzo, M G; Crescenzi, M; Sacchi, A

    1996-01-01

    Expression of exogenous wild-type (wt) p53 in different leukemia cell lines can induce growth arrest, apoptotic cell death, or cell differentiation. The hematopoietic cell lines that have been used so far to study wt p53 functions have in common the characteristic of not expressing endogenous p53. However, the mechanisms involved in the transformation of these cells are different, and the cells are at different stages of tumor progression. It can be postulated that each type of neoplastic cell offers a particular environment in which p53 might generate different effects. To test this hypothesis, we introduced individual oncogenes into untransformed, interleukin-3 (IL-3)-dependent myeloid precursor 32D cells to have a single transforming agent at a time. The effects induced by wt p53 overexpression were subsequently evaluated in each oncogene-expressing 32D derivative. We found that in not fully transformed, v-ras-expressing 32D cells, as already shown for the parental 32D cells, overexpression of the wt p53 gene caused no phenotypic changes and no reduction of the proliferative rate as long as the cells were maintained in their normal culture conditions (presence of IL-3 and serum). An accelerated rate of apoptosis was observed after IL-3 withdrawal. In contrast, in transformed, IL-3-independent 32D cells, wt p53 overexpression induced different effects. The v-abl-transformed cells manifested a reduction in growth rate, while the v-src-transformed cells underwent monocytic differentiation. These results show that the phenotype effects of wt p53 action(s) can vary as a function of the cellular environment. PMID:8552075

  18. Enhanced human papillomavirus type 8 oncogene expression levels are crucial for skin tumorigenesis in transgenic mice

    SciTech Connect

    Hufbauer, M.; Lazic, D.; Akguel, B.; Brandsma, J.L.; Pfister, H.; Weissenborn, S.J.

    2010-08-01

    Human papillomavirus 8 (HPV8) is involved in skin cancer development in epidermodysplasia verruciformis patients. Transgenic mice expressing HPV8 early genes (HPV8-CER) developed papillomas, dysplasias and squamous cell carcinomas. UVA/B-irradiation and mechanical wounding of HPV8-CER mouse skin led to prompt papilloma induction in about 3 weeks. The aim of this study was to analyze the kinetics and level of transgene expression in response to skin irritations. Transgene expression was already enhanced 1 to 2 days after UVA/B-irradiation or tape-stripping and maintained during papilloma development. The enhanced transgene expression could be assigned to UVB and not to UVA. Papilloma development was thus always paralleled by an increased transgene expression irrespective of the type of skin irritation. A knock-down of E6 mRNA by tattooing HPV8-E6-specific siRNA led to a delay and a lower incidence of papilloma development. This indicates that the early increase of viral oncogene expression is crucial for induction of papillomatosis.

  19. Expression of the proto-oncogene Fos after exposure to radiofrequency radiation relevant to wireless communications.

    PubMed

    Whitehead, Timothy D; Brownstein, Bernard H; Parry, Jesse J; Thompson, Dominic; Cha, Bibianna A; Moros, Eduardo G; Rogers, Buck E; Roti Roti, Joseph L

    2005-10-01

    In this study the expression levels of the proto-oncogene Fos were measured after exposure to radiofrequency (RF) radiation at two relatively high specific absorption rates (SARs) of 5 and 10 W/kg for three types of modulated signals: 847.74 MHz code division multiple access (CDMA), 835.62 MHz frequency division multiple access (FDMA), and 836.55 MHz time division multiple access (TDMA). This work was undertaken to confirm a previous report by Goswami et al. (Radiat. Res. 151, 300-309, 1999) that CDMA and FDMA radiation caused small but statistically significant increases in Fos levels as cells entered plateau phase during exposure. No effects on Myc or Jun levels were observed in that study. Therefore, in the present study, analyses were restricted to Fos expression during the transition from exponential growth to plateau phase. Fos expression was measured using the real-time polymerase chain reaction (RT-PCR) technique. Serum-stimulated C3H 10T(1/2) cells were used as a positive control for Fos expression. Possible influences of final cell number or pH variability on Fos expression were evaluated. Expression of Fos mRNA in C3H 10T(1/2) cells was not significantly different from that found after sham exposure at either SAR level for any signal modulation. Therefore, the results of Goswami et al. could not be confirmed.

  20. Arsenic trioxide inhibits cell proliferation and human papillomavirus oncogene expression in cervical cancer cells

    SciTech Connect

    Wang, Hongtao; Gao, Peng; Zheng, Jie

    2014-09-05

    Highlights: • As{sub 2}O{sub 3} inhibits growth of cervical cancer cells and expression of HPV oncogenes in these cells. • HPV-negative cervical cancer cells are more sensitive to As{sub 2}O{sub 3} than HPV-positive cervical cancer cells. • HPV-18 positive cervical cancer cells are more sensitive to As{sub 2}O{sub 3} than HPV-16 positive cancer cells. • Down-regulation of HPV oncogenes by As{sub 2}O{sub 3} is partially due to the diminished AP-1 binding. - Abstract: Arsenic trioxide (As{sub 2}O{sub 3}) has shown therapeutic effects in some leukemias and solid cancers. However, the molecular mechanisms of its anticancer efficacy have not been clearly elucidated, particularly in solid cancers. Our previous data showed that As{sub 2}O{sub 3} induced apoptosis of human papillomavirus (HPV) 16 DNA-immortalized human cervical epithelial cells and cervical cancer cells and inhibited the expression of HPV oncogenes in these cells. In the present study, we systemically examined the effects of As{sub 2}O{sub 3} on five human cervical cancer cell lines and explored the possible molecular mechanisms. MTT assay showed that HPV-negative C33A cells were more sensitive to growth inhibition induced by As{sub 2}O{sub 3} than HPV-positive cervical cancer cells, and HPV 18-positive HeLa and C4-I cells were more sensitive to As{sub 2}O{sub 3} than HPV 16-positive CaSki and SiHa cells. After As{sub 2}O{sub 3} treatment, both mRNA and protein levels of HPV E6 and E7 obviously decreased in all HPV positive cell lines. In contrast, p53 and Rb protein levels increased in all tested cell lines. Transcription factor AP-1 protein expression decreased significantly in HeLa, CaSki and C33A cells with ELISA method. These results suggest that As{sub 2}O{sub 3} is a potential anticancer drug for cervical cancer.

  1. Oncogenic Ras promotes butyrate-induced apoptosis through inhibition of gelsolin expression.

    PubMed

    Klampfer, Lidija; Huang, Jie; Sasazuki, Takehiko; Shirasawa, Senji; Augenlicht, Leonard

    2004-08-27

    Activation of Ras promotes oncogenesis by altering a multiple of cellular processes, such as cell cycle progression, differentiation, and apoptosis. Oncogenic Ras can either promote or inhibit apoptosis, depending on the cell type and the nature of the apoptotic stimuli. The response of normal and transformed colonic epithelial cells to the short chain fatty acid butyrate, a physiological regulator of epithelial cell maturation, is also divergent: normal epithelial cells proliferate, and transformed cells undergo apoptosis in response to butyrate. To investigate the role of k-ras mutations in butyrate-induced apoptosis, we utilized HCT116 cells, which harbor an oncogenic k-ras mutation and two isogenic clones with targeted inactivation of the mutant k-ras allele, Hkh2, and Hke-3. We demonstrated that the targeted deletion of the mutant k-ras allele is sufficient to protect epithelial cells from butyrate-induced apoptosis. Consistent with this, we showed that apigenin, a dietary flavonoid that has been shown to inhibit Ras signaling and to reverse transformation of cancer cell lines, prevented butyrate-induced apoptosis in HCT116 cells. To investigate the mechanism whereby activated k-ras sensitizes colonic cells to butyrate, we performed a genome-wide analysis of Ras target genes in the isogenic cell lines HCT116, Hkh2, and Hke-3. The gene exhibiting the greatest down-regulation by the activating k-ras mutation was gelsolin, an actin-binding protein whose expression is frequently reduced or absent in colorectal cancer cell lines and primary tumors. We demonstrated that silencing of gelsolin expression by small interfering RNA sensitized cells to butyrate-induced apoptosis through amplification of the activation of caspase-9 and caspase-7. These data therefore demonstrate that gelsolin protects cells from butyrate-induced apoptosis and suggest that Ras promotes apoptosis, at least in part, through its ability to down-regulate the expression of gelsolin.

  2. Osteofibrous dysplasia and adamantinoma: correlation of proto-oncogene product and matrix protein expression.

    PubMed

    Maki, Masahiiko; Athanasou, Nicholas

    2004-01-01

    To investigate the relationship between osteofibrous dysplasia (OFD) and adamantinoma, we analyzed the expression of several proto-oncogene products and extracellular matrix proteins by immunohistochemistry and correlated our results with histological and ultrastructural findings. C-fos and c-jun, but not c-Met, were observed in OFD and in the fibrous and epithelial components of differentiated and classical adamantinomas. Staining for collagen IV, laminin and galectin-3, a laminin binding protein was seen in OFD and around cell nests in adamantinoma. E-, P-, and N-cadherin expression was found in all cases of classical adamantinoma, but not in differentiated adamantinoma or OFD. Osteonectin was detected in both the epithelial and fibrous components of adamantinomas, but osteopontin and osteocalcin were not seen in classical adamantinomas. The results show common expression of a number of oncoproteins and bone matrix proteins in adamantinoma and OFD, some of which are associated with mesenchymal-to-epithelial cell transformation. These findings would be in keeping with the hypothesis that OFD represents a precursor lesion of adamantinoma. Differential expression of a number of bone matrix protein in adamantinoma may also be of diagnostic use in distinguishing these 2 lesions immunohistochemically.

  3. Dbl oncogene expression in MCF-10 A epithelial cells disrupts mammary acinar architecture, induces EMT and angiogenic factor secretion

    PubMed Central

    Vanni, Cristina; Ognibene, Marzia; Finetti, Federica; Mancini, Patrizia; Cabodi, Sara; Segalerba, Daniela; Torrisi, Maria Rosaria; Donnini, Sandra; Bosco, Maria Carla; Varesio, Luigi; Eva, Alessandra

    2015-01-01

    The proteins of the Dbl family are guanine nucleotide exchange factors (GEFs) of Rho GTPases and are known to be involved in cell growth regulation. Alterations of the normal function of these proteins lead to pathological processes such as developmental disorders, neoplastic transformation, and tumor metastasis. We have previously demonstrated that expression of Dbl oncogene in lens epithelial cells modulates genes encoding proteins involved in epithelial-mesenchymal-transition (EMT) and induces angiogenesis in the lens. Our present study was undertaken to investigate the role of Dbl oncogene in epithelial cells transformation, providing new insights into carcinoma progression.To assess how Dbl oncogene can modulate EMT, cell migration, morphogenesis, and expression of pro-apoptotic and angiogenic factors we utilized bi- and 3-dimensional cultures of MCF-10 A cells. We show that upon Dbl expression MCF-10 A cells undergo EMT. In addition, we found that Dbl overexpression sustains Cdc42 and Rac activation inducing morphological alterations, characterized by the presence of lamellipodia and conferring a high migratory capacity to the cells. Moreover, Dbl expressing MCF-10 A cells form altered 3D structures and can induce angiogenesis by producing proangiogenic factors such as CCL2. These results support a role for Dbl oncogene in epithelial cell differentiation and transformation and suggest the relevance of GEF deregulation in tumor onset and progression. PMID:25723869

  4. Dbl oncogene expression in MCF-10 A epithelial cells disrupts mammary acinar architecture, induces EMT and angiogenic factor secretion.

    PubMed

    Vanni, Cristina; Ognibene, Marzia; Finetti, Federica; Mancini, Patrizia; Cabodi, Sara; Segalerba, Daniela; Torrisi, Maria Rosaria; Donnini, Sandra; Bosco, Maria Carla; Varesio, Luigi; Eva, Alessandra

    2015-01-01

    The proteins of the Dbl family are guanine nucleotide exchange factors (GEFs) of Rho GTPases and are known to be involved in cell growth regulation. Alterations of the normal function of these proteins lead to pathological processes such as developmental disorders, neoplastic transformation, and tumor metastasis. We have previously demonstrated that expression of Dbl oncogene in lens epithelial cells modulates genes encoding proteins involved in epithelial-mesenchymal-transition (EMT) and induces angiogenesis in the lens. Our present study was undertaken to investigate the role of Dbl oncogene in epithelial cells transformation, providing new insights into carcinoma progression.To assess how Dbl oncogene can modulate EMT, cell migration, morphogenesis, and expression of pro-apoptotic and angiogenic factors we utilized bi- and 3-dimensional cultures of MCF-10 A cells. We show that upon Dbl expression MCF-10 A cells undergo EMT. In addition, we found that Dbl overexpression sustains Cdc42 and Rac activation inducing morphological alterations, characterized by the presence of lamellipodia and conferring a high migratory capacity to the cells. Moreover, Dbl expressing MCF-10 A cells form altered 3D structures and can induce angiogenesis by producing proangiogenic factors such as CCL2. These results support a role for Dbl oncogene in epithelial cell differentiation and transformation and suggest the relevance of GEF deregulation in tumor onset and progression.

  5. Tumor markers and oncogene expression in thyroid cancer using biochemical and immunohistochemical studies.

    PubMed

    Hashimoto, T; Matsubara, F; Mizukami, Y; Miyazaki, I; Michigishi, T; Yanaihara, N

    1990-04-01

    In 111 thyroid cancer patients consisting of 89 papillary carcinomas, 17 follicular carcinomas, 2 medullary carcinomas, 1 squamous cell carcinoma and 2 malignant lymphomas, the levels of 12 tumor markers, including thyroglobulin (Tg), were measured in the serum by radioimmunoassay and radioimmunoassay related methods. Serum levels of Tg were elevated in 58.6%, those of CA-M26 in 15.7%, CA 19-9 in 5.3%, CT in 3.6%, NSE in 3.6%, CA 15-3 in 2.6%, CA 125 in 2.6%, CEA in 0.9%, CA-M 29 in 0%, ferritin in 0%, SCC in 0% and AFP in 0% of cases. Among the patients, there was a case of thyroid carcinoma secreting thyroglobulin and CA 19-9, both of whose titer decreased after surgery. Immunohistochemical studies were carried out on 57 of the above mentioned patients plus 6 anaplastic carcinomas, 15 adenomas, 5 adenomatous goiters, 6 Hashimoto's thyroiditis, 15 Graves' disease and 15 normal subjects. CA 19-9 was positive in 58% of the papillary carcinomas, EGF in 73% of papillary carcinomas, 67% of anaplastic carcinomas, and 33% of follicular carcinomas, while EGF-R was found in 73% of the papillary carcinomas, and 33% of the follicular carcinomas. Enhanced expression of ras p 21 oncogene and (c-myc oncogene) was demonstrated in 100% (100%) of anaplastic carcinomas, in 100% (67%) of follicular carcinomas and in 63% (90%) of papillary carcinomas. Our results indicate that a better tumor marker is required and more extensive molecular oncology research should be pursued.

  6. Posttranscriptional regulation of cellular gene expression by the c-myc oncogene

    SciTech Connect

    Prendergast, G.C.; Cole, M.D. . Dept. of Biology)

    1989-01-01

    The c-myc oncogene has been implicated in the development of many different cancers, yet the mechanism by which the c-myc protein alters cellular growth control has proven elusive. The authors used a cDNA hybridization difference assay to isolate two genes, mr1 and mr2, that were constitutively expressed (i.e., deregulated) in rodent fibroblast cell lines immortalized by transfection of a viral promoter-linked c-myc gene. Both cDNAs were serum inducible in quiescent G/sub o/ fibroblasts, suggesting that they are functionally related to cellular proliferative processes. Although there were significant differences in cytoplasmic mRNA levels between myc-immortalized and control cells, the rates of transcription and mRNA turnover of both genes were similar, suggesting that c-myc regulates mr1 and mr2 expression by some nuclear posttranscriptional mechanism. Their results provide evidence that c-myc can rapidly modulate cellular gene expression and suggest that c-myc may function in gene regulation at the level of RNA export, splicing, or nuclear RNA turnover.

  7. Expression of the Ets-1 proto-oncogene in human gastric carcinoma: correlation with tumor invasion.

    PubMed Central

    Nakayama, T.; Ito, M.; Ohtsuru, A.; Naito, S.; Nakashima, M.; Fagin, J. A.; Yamashita, S.; Sekine, I.

    1996-01-01

    The proto-oncogene Ets-1 is a transcription factor known to control the expression of a number of genes involved in extracellular matrix remodeling and has been postulated to play a role in cell migration and tumor invasion. To elucidate the involvement of Ets-1 in human gastric carcinomas, we examined 11 cases of gastric adenoma and 110 cases of gastric carcinoma by immunohistochemistry and compared the degree of Ets-1 expression with the depth of carcinoma invasion. Ets-1 was not expressed either in the normal gastric epithelium or in gastric adenomas. Among the 110 cases with gastric adenocarcinoma, 70 (63.6%) showed positive staining for the Ets-1 protein. In mucosal carcinomas, only 3 of 26 cases (11.5%) showed positive immunostaining for Ets-1. In contrast, 67 of 84 cases (79.8%) with submucosal or more invasive carcinomas showed immunopositivity and intense staining for Ets-1 in the tumor cells. The pattern of Ets-1 immunostaining in mucosal carcinomas was weak and differed from that of other local invasive carcinomas (P < 0.001). Histologically, signet-ring cell and mucinous carcinomas expressed relatively weak positivity for Ets-1. Ets-1 expression correlated significantly with the presence of lymph node metastasis (P < 0.001). In situ hybridization, using an Ets-1 oligonucleotide probe, also confirmed the presence of Ets-1 mRNA in gastric carcinomas. Expression of Ets-1 mRNA was also detected in four different kinds of cultured human gastric carcinoma cell lines by the reverse transcription polymerase chain reaction method. These findings suggest that Ets-1 is overexpressed in gastric mucosal cells that have undergone malignant conversion and that Ets-1 is one of the factors involved in the penetration of gastric carcinoma beyond the muscularis mucosa. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:8952528

  8. Proliferative response and oncogene expression induced by epidermal growth factor in EL2 rat fibroblasts.

    PubMed

    Liboi, E; Pelosi, E; Testa, U; Peschle, C; Rossi, G B

    1986-06-01

    Extensive evidence supports a two-step model for the control of fibroblast growth, which includes first the action of a competence factor (e.g., platelet-derived growth factor) followed by the stimulus of a progression factor (e.g., epidermal growth factor [EGF]). We investigated whether this model may be applied to the euploid EL2 fibroblast line recently isolated from rat embryos (E. Liboi, M. Caruso, and C. Basilico, Mol. Cell. Biol. 4:2925-2928, 1984). Our results clearly show that EGF alone leads EL2 cells to proliferate in serum-free conditions at a rate corresponding to 50 to 60% of that observed in the presence of 10% calf serum. It is of interest that, when resting EL2 cells were exposed to EGF, transcription of both c-myc and c-fos was markedly induced. Altogether, these observations suggest that, in contrast with the model of fibroblast growth mentioned above, EL2 cells require the presence of a single growth factor (EGF) for induction of DNA synthesis, and the expression of myc and fos proto-oncogenes may represent an obligatory step in the pathway of commitment of EL2 cells to proliferation. In addition, we showed that EGF may induce EL2 cells to acquire some properties of transformed cells, such as growth in agar and loss of contact inhibition. This suggests that the particular response to EGF of the EL2 line may be strictly connected with the expression of a transformed phenotype.

  9. Arsenic trioxide inhibits cell proliferation and human papillomavirus oncogene expression in cervical cancer cells.

    PubMed

    Wang, Hongtao; Gao, Peng; Zheng, Jie

    2014-09-05

    Arsenic trioxide (As2O3) has shown therapeutic effects in some leukemias and solid cancers. However, the molecular mechanisms of its anticancer efficacy have not been clearly elucidated, particularly in solid cancers. Our previous data showed that As2O3 induced apoptosis of human papillomavirus (HPV) 16 DNA-immortalized human cervical epithelial cells and cervical cancer cells and inhibited the expression of HPV oncogenes in these cells. In the present study, we systemically examined the effects of As2O3 on five human cervical cancer cell lines and explored the possible molecular mechanisms. MTT assay showed that HPV-negative C33A cells were more sensitive to growth inhibition induced by As2O3 than HPV-positive cervical cancer cells, and HPV 18-positive HeLa and C4-I cells were more sensitive to As2O3 than HPV 16-positive CaSki and SiHa cells. After As2O3 treatment, both mRNA and protein levels of HPV E6 and E7 obviously decreased in all HPV positive cell lines. In contrast, p53 and Rb protein levels increased in all tested cell lines. Transcription factor AP-1 protein expression decreased significantly in HeLa, CaSki and C33A cells with ELISA method. These results suggest that As2O3 is a potential anticancer drug for cervical cancer.

  10. ZYG11A serves as an oncogene in non-small cell lung cancer and influences CCNE1 expression

    PubMed Central

    Wang, Xin; Sun, Qi; Chen, Chen; Yin, Rong; Huang, Xing; Wang, Xuan; Shi, Run; Xu, Lin; Ren, Binhui

    2016-01-01

    By analyzing The Cancer Genome Atlas (TCGA) database, we identified ZYG11A as a potential oncogene. We determined the expression of ZYG11A in NSCLC tissues and explored its clinical significance. And also evaluated the effects of ZYG11A on NSCLC cell proliferation, migration, and invasion both in vitro and in vivo. Our results show that ZYG11A is hyper-expressed in NSCLC tissues compared to adjacent normal tissues, and increased expression of ZYG11A is associated with a poor prognosis (HR: 2.489, 95%CI: 1.248-4.963, p = 0.010). ZYG11A knockdown induces cell cycle arrest and inhibits proliferation, migration, and invasion of NSCLC cells. ZYG11A knockdown also results in decreased expression of CCNE1. Over-expression of CCNE1 in cells with ZYG11A knockdown restores their oncogenic activities. Our data suggest that ZYG11A may serve as a novel oncogene promoting tumorigenicity of NSCLC cells by inducing cell cycle alterations and increasing CCNE1 expression. PMID:26771237

  11. The MYC 3′ Wnt-Responsive Element Drives Oncogenic MYC Expression in Human Colorectal Cancer Cells

    PubMed Central

    Rennoll, Sherri A.; Eshelman, Melanie A.; Raup-Konsavage, Wesley M.; Kawasawa, Yuka Imamura; Yochum, Gregory S.

    2016-01-01

    Mutations in components of the Wnt/β-catenin signaling pathway drive colorectal cancer (CRC) by deregulating expression of downstream target genes including the c-MYC proto-oncogene (MYC). The critical regulatory DNA enhancer elements that control oncogenic MYC expression in CRC have yet to be fully elucidated. In previous reports, we correlated T-cell factor (TCF) and β-catenin binding to the MYC 3′ Wnt responsive DNA element (MYC 3′ WRE) with MYC expression in HCT116 cells. Here we used CRISPR/Cas9 to determine whether this element is a critical driver of MYC. We isolated a clonal population of cells that contained a deletion of a single TCF binding element (TBE) within the MYC 3′ WRE. This deletion reduced TCF/β-catenin binding to this regulatory element and decreased MYC expression. Using RNA-Seq analysis, we found altered expression of genes that regulate metabolic processes, many of which are known MYC target genes. We found that 3′ WRE-Mut cells displayed a reduced proliferative capacity, diminished clonogenic growth, and a decreased potential to form tumors in vivo. These findings indicate that the MYC 3′ WRE is a critical driver of oncogenic MYC expression and suggest that this element may serve as a therapeutic target for CRC. PMID:27223305

  12. Integrative analysis reveals clinical phenotypes and oncogenic potentials of long non-coding RNAs across 15 cancer types

    PubMed Central

    Piccolo, Stephen R.; Zhang, Xiao-Qin; Li, Jun-Hao; Zhou, Hui; Yang, Jian-Hua; Qu, Liang-Hu

    2016-01-01

    Long non-coding RNAs (lncRNAs) have been shown to contribute to tumorigenesis. However, surprisingly little is known about the comprehensive clinical and genomic characterization of lncRNAs across human cancer. In this study, we conducted comprehensive analyses for the expression profile, clinical outcomes, somatic copy number alterations (SCNAs) profile of lncRNAs in ~7000 clinical samples from 15 different cancer types. We identified significantly differentially expressed lncRNAs between tumor and normal tissues from each cancer. Notably, we characterized 47 lncRNAs which were extensively dysregulated in at least 10 cancer types, suggesting a conserved function in cancer development. We also analyzed the associations between lncRNA expressions and patient survival, and identified sets of lncRNAs that possessed significant prognostic values in specific cancer types. Our combined analysis of SCNA data and expression data uncovered 116 dysregulated lncRNAs are strikingly genomic altered across 15 cancer types, indicating their oncogenic potentials. Our study may lay the groundwork for future functional studies of lncRNAs and help facilitate the discovery of novel clinical biomarkers. PMID:27147563

  13. Intestine-specific homeobox (ISX) upregulates E2F1 expression and related oncogenic activities in HCC

    PubMed Central

    Chai, Chee-Yin; Hsi, Edward; Kuo, Hsing-Tao; Yokoyama, Kazunari K.; Hsu, Shih-Hsien

    2016-01-01

    Intestine-specific homeobox (ISX), a newly identified proto-oncogene, is involved in cell proliferation and progression of hepatocellular carcinoma (HCC). However, the underlying mechanisms linking gene expression and tumor formation remain unclear. In this study, we found that ISX transcriptionally activated E2F transcription factor 1 (E2F1) and associated oncogenic activity by directly binding to the E2 site of its promoter. Forced expression of ISX increased the expression of and phosphorylated the serine residue at position 332 of E2F1, which may be translocated into the nucleus to form the E2F1–DP-1 complex, suggesting that the promotion of oncogenic activities of the ISX–E2F1 axis plays a critical role in hepatoma cells. Coexpression of ISX and E2F1 significantly promoted p53 and RB-mediated cell proliferation and anti-apoptosis, and repressed apoptosis and autophagy. In contrast, short hairpin RNAi-mediated attenuation of ISX and E2F1 decreased cell proliferation and malignant transformation, respectively, in hepatoma cells in vitro and in vivo. The mRNA expression of E2F1 and ISX in 238 paired specimens from human HCC patients, and the adjacent, normal tissues exhibited a tumor-specific expression pattern which was highly correlated with disease pathogenesis, patient survival time, progression stage, and poor prognosis. Therefore, our results indicate that E2F1 is an important downstream gene of ISX in hepatoma progression. PMID:27175585

  14. Oncogenic ras-induced expression of cytokines: a new target of anti-cancer therapeutics.

    PubMed

    Ancrile, Brooke B; O'Hayer, Kevin M; Counter, Christopher M

    2008-02-01

    The Ras family of small guanosine triphosphatases normally transmit signals from cell surface receptors to the interior of the cell. Stimulation of cell surface receptors leads to the activation of guanine exchange factors, which, in turn, convert Ras from an inactive GDP-bound state to an active GTP-bound state. However, in one third of human cancers, RAS is mutated and remains in the constitutively active GTP-bound state. In this oncogenic state, RAS activates a constellation of signaling that is known to promote tumorigenesis. One consequence of this oncogenic RAS signal in cancer cells is the upregulation of the cytokines interleukin (IL)-6, IL-8, and chemokine growth-regulated oncogene 1 (GRO-1). We review the evidence supporting a role for these cytokines in oncogenic RAS-driven solid tumors.

  15. Immortality, but not oncogenic transformation, of primary human cells leads to epigenetic reprogramming of DNA methylation and gene expression.

    PubMed

    Gordon, Katrina; Clouaire, Thomas; Bao, Xun X; Kemp, Sadie E; Xenophontos, Maria; de Las Heras, Jose Ignacio; Stancheva, Irina

    2014-04-01

    Tumourigenic transformation of normal cells into cancer typically involves several steps resulting in acquisition of unlimited growth potential, evasion of apoptosis and non-responsiveness to growth inhibitory signals. Both genetic and epigenetic changes can contribute to cancer development and progression. Given the vast genetic heterogeneity of human cancers and difficulty to monitor cancer-initiating events in vivo, the precise relationship between acquisition of genetic mutations and the temporal progression of epigenetic alterations in transformed cells is largely unclear. Here, we use an in vitro model system to investigate the contribution of cellular immortality and oncogenic transformation of primary human cells to epigenetic reprogramming of DNA methylation and gene expression. Our data demonstrate that extension of replicative life span of the cells is sufficient to induce accumulation of DNA methylation at gene promoters and large-scale changes in gene expression in a time-dependent manner. In contrast, continuous expression of cooperating oncogenes in immortalized cells, although essential for anchorage-independent growth and evasion of apoptosis, does not affect de novo DNA methylation at promoters and induces subtle expression changes. Taken together, these observations imply that cellular immortality promotes epigenetic adaptation to highly proliferative state, whereas transforming oncogenes confer additional properties to transformed human cells.

  16. ELF4/MEF activates MDM2 expression and blocks oncogene-induced p16 activation to promote transformation.

    PubMed

    Sashida, Goro; Liu, Yan; Elf, Shannon; Miyata, Yasuhiko; Ohyashiki, Kazuma; Izumi, Miki; Menendez, Silvia; Nimer, Stephen D

    2009-07-01

    Several ETS transcription factors, including ELF4/MEF, can function as oncogenes in murine cancer models and are overexpressed in human cancer. We found that Elf4/Mef activates Mdm2 expression; thus, lack of or knockdown of Elf4/Mef reduces Mdm2 levels in mouse embryonic fibroblasts (mef's), leading to enhanced p53 protein accumulation and p53-dependent senescence. Even though p53 is absent in Elf4(-/-) p53(-/-) mef's, neither oncogenic H-Ras(V12) nor c-myc can induce transformation of these cells. This appears to relate to the INK4a/ARF locus; both p19(ARF) and p16 are increased in Elf4(-/-) p53(-/-) mef's, and expression of Bmi-1 or knockdown of p16 in this context restores H-Ras(V12)-induced transformation. Thus, ELF4/MEF promotes tumorigenesis by inhibiting both the p53 and p16/Rb pathways.

  17. Comprehensive analysis of cellular galectin-3 reveals no consistent oncogenic function in pancreatic cancer cells.

    PubMed

    Hann, Alexander; Gruner, Anja; Chen, Ying; Gress, Thomas M; Buchholz, Malte

    2011-01-01

    Galectin-3 (Gal-3), a 31 kDa member of the family of beta-galactoside-binding proteins, has been implicated in the progression of different human cancers. However, the proposed roles differ widely, ranging from tumor-promoting cellular functions and negative impact on patient prognosis to tumor-suppressive properties and positive prognostic impact. We and others have previously identified Gal-3 as overexpressed in pancreatic cancer as compared to chronic pancreatitis and normal pancreatic tissue. The purpose of this study was thus the comprehensive analysis of putative cellular functions of Gal-3 by transient as well as stable silencing or overexpression of Gal-3 in a panel of 6 well-established pancreatic cancer cell lines. Our results confirm that galectin-3 is upregulated at the mRNA level in pancreatic cancer and strongly expressed in the majority of pancreatic cancer cell lines. In individual cell lines, transient knockdown of Gal-3 expression resulted in moderate inhibitory effects on proliferation, migration or anchorage-independent growth of the cells, but these effects were not consistent across the spectrum of analyzed cell lines. Moreover, functional effects of the modulation of Gal-3 expression were not observed in stable knockdown or overexpression approaches in vitro and did not alter the growth characteristics of nude mouse xenograft tumors in vivo. Our data thus do not support a direct functional role of Gal-3 in the malignant transformation of pancreatic epithelial cells, although paracrine or systemic effects of Gal-3 expression are not excluded.

  18. Deregulated miRNAs in Hereditary Breast Cancer Revealed a Role for miR-30c in Regulating KRAS Oncogene

    PubMed Central

    Tanic, Miljana; Yanowsky, Kira; Rodriguez-Antona, Cristina; Andrés, Raquel; Márquez-Rodas, Iván; Osorio, Ana; Benitez, Javier; Martinez-Delgado, Beatriz

    2012-01-01

    Aberrant miRNA expression has been previously established in breast cancer and has clinical relevance. However, no studies so far have defined miRNAs deregulated in hereditary breast tumors. In this study we investigated the role of miRNAs in hereditary breast tumors comparing with normal breast tissue. Global miRNA expression profiling using Exiqon microarrays was performed on 22 hereditary breast tumors and 15 non-tumoral breast tissues. We identified 19 miRNAs differentially expressed, most of them down-regulated in tumors. An important proportion of deregulated miRNAs in hereditary tumors were previously identified commonly deregulated in sporadic breast tumors. Under-expression of these miRNAs was validated by qRT-PCR in additional 18 sporadic breast tumors and their normal breast tissue counterparts. Pathway enrichment analysis revealed that deregulated miRNAs collectively targeted a number of genes belonging to signaling pathways such as MAPK, ErbB, mTOR, and those regulating cell motility or adhesion. In silico prediction detected KRAS oncogene as target of several deregulated miRNAs. In particular, we experimentally validated KRAS as a miR-30c target. Luciferase assays confirmed that miR-30c binds the 3′UTR of KRAS transcripts and expression of pre-miR-30c down-regulated KRAS mRNA and protein. Furthermore, miR-30c overexpression inhibited proliferation of breast cancer cells. Our results identify miRNAs associated to hereditary breast cancer, as well as miRNAs commonly miss-expressed in hereditary and sporadic tumors, suggesting common underlying mechanisms of tumor progression. In addition, we provide evidence that KRAS is a target of miR-30c, and that this miRNA suppresses breast cancer cell growth potentially through inhibition of KRAS signaling. PMID:22701724

  19. Tal1 transgenic expression reveals absence of B lymphocytes.

    PubMed

    Palamarchuk, Alexey; Zanesi, Nicola; Aqeilan, Rami I; Efanov, Alexey; Maximov, Vadim; Santanam, Urmila; Hagan, John P; Croce, Carlo M; Pekarsky, Yuri

    2006-06-15

    TAL1 oncogene encodes a helix-loop-helix transcription factor, Tal1, which is required for blood cell development, and its activation is a frequent event in T-cell acute lymphoblastic leukemia. Tal1 interacts and inhibits other helix-loop-helix factors such as E47 and HEB. To investigate the function of Tal1 in B cells, we generated Emu-TAL1 transgenic mouse line, expressing Tal1 in mouse B-cell lineage. Fluorescence-activated cell sorting (FACS) analysis of lymphocytes isolated from spleens of five out of five founders reveals complete absence of IgM- or CD19-expressing cells. Only 2% to 3% of these cells were B220+ and 100% of B220+ cells were CD43+, indicating that these mice were able to make pro-B cells. Similarly, FACS analysis of bone marrow cells in Emu-TAL1 mice revealed complete absence of B220+IgM+ and B220+CD19+ cells. Analysis of the recombination status of IgH genes revealed the presence of D-J but absence or drastic reduction of V-D-J rearrangements. Our results suggest that Tal1 overexpression in B cells results in a phenotype similar to that of B cells of E47/E2A knockout animals. This represents first in vivo evidence that Tal1 can completely inhibit E47/E2A function.

  20. Potential microRNA-mediated oncogenic intercellular communication revealed by pan-cancer analysis

    NASA Astrophysics Data System (ADS)

    Li, Yue; Zhang, Zhaolei

    2014-11-01

    Carcinogenesis consists of oncogenesis and metastasis, and intriguingly microRNAs (miRNAs) are involved in both processes. Although aberrant miRNA activities are prevalent in diverse tumor types, the exact mechanisms for how they regulate cancerous processes are not always clear. To this end, we performed a large-scale pan-cancer analysis via a novel probabilistic approach to infer recurrent miRNA-target interactions implicated in 12 cancer types using data from The Cancer Genome Atlas. We discovered ~20,000 recurrent miRNA regulations, which are enriched for cancer-related miRNAs/genes. Notably, miRNA 200 family (miR-200/141/429) is among the most prominent miRNA regulators, which is known to be involved in metastasis. Importantly, the recurrent miRNA regulatory network is not only enriched for cancer pathways but also for extracellular matrix (ECM) organization and ECM-receptor interactions. The results suggest an intriguing cancer mechanism involving miRNA-mediated cell-to-cell communication, which possibly involves delivery of tumorigenic miRNA messengers to adjacent cells via exosomes. Finally, survival analysis revealed 414 recurrent-prognostic associations, where both gene and miRNA involved in each interaction conferred significant prognostic power in one or more cancer types. Together, our comprehensive pan-cancer analysis provided not only biological insights into metastasis but also brought to bear the clinical relevance of the proposed recurrent miRNA-gene associations.

  1. Potential microRNA-mediated oncogenic intercellular communication revealed by pan-cancer analysis.

    PubMed

    Li, Yue; Zhang, Zhaolei

    2014-11-18

    Carcinogenesis consists of oncogenesis and metastasis, and intriguingly microRNAs (miRNAs) are involved in both processes. Although aberrant miRNA activities are prevalent in diverse tumor types, the exact mechanisms for how they regulate cancerous processes are not always clear. To this end, we performed a large-scale pan-cancer analysis via a novel probabilistic approach to infer recurrent miRNA-target interactions implicated in 12 cancer types using data from The Cancer Genome Atlas. We discovered ~20,000 recurrent miRNA regulations, which are enriched for cancer-related miRNAs/genes. Notably, miRNA 200 family (miR-200/141/429) is among the most prominent miRNA regulators, which is known to be involved in metastasis. Importantly, the recurrent miRNA regulatory network is not only enriched for cancer pathways but also for extracellular matrix (ECM) organization and ECM-receptor interactions. The results suggest an intriguing cancer mechanism involving miRNA-mediated cell-to-cell communication, which possibly involves delivery of tumorigenic miRNA messengers to adjacent cells via exosomes. Finally, survival analysis revealed 414 recurrent-prognostic associations, where both gene and miRNA involved in each interaction conferred significant prognostic power in one or more cancer types. Together, our comprehensive pan-cancer analysis provided not only biological insights into metastasis but also brought to bear the clinical relevance of the proposed recurrent miRNA-gene associations.

  2. Mitochondrial STAT3 contributes to transformation of Barrett's epithelial cells that express oncogenic Ras in a p53-independent fashion.

    PubMed

    Yu, Chunhua; Huo, Xiaofang; Agoston, Agoston T; Zhang, Xi; Theiss, Arianne L; Cheng, Edaire; Zhang, Qiuyang; Zaika, Alexander; Pham, Thai H; Wang, David H; Lobie, Peter E; Odze, Robert D; Spechler, Stuart J; Souza, Rhonda F

    2015-08-01

    Metaplastic epithelial cells of Barrett's esophagus transformed by the combination of p53-knockdown and oncogenic Ras expression are known to activate signal transducer and activator of transcription 3 (STAT3). When phosphorylated at tyrosine 705 (Tyr705), STAT3 functions as a nuclear transcription factor that can contribute to oncogenesis. STAT3 phosphorylated at serine 727 (Ser727) localizes in mitochondria, but little is known about mitochondrial STAT3's contribution to carcinogenesis in Barrett's esophagus, which is the focus of this study. We introduced a constitutively active variant of human STAT3 (STAT3CA) into the following: 1) non-neoplastic Barrett's (BAR-T) cells; 2) BAR-T cells with p53 knockdown; and 3) BAR-T cells that express oncogenic H-Ras(G12V). STAT3CA transformed only the H-Ras(G12V)-expressing BAR-T cells (evidenced by loss of contact inhibition, formation of colonies in soft agar, and generation of tumors in immunodeficient mice), and did so in a p53-independent fashion. The transformed cells had elevated levels of both mitochondrial (Ser727) and nuclear (Tyr705) phospho-STAT3. Introduction of a STAT3CA construct with a mutated tyrosine phosphorylation site into H-Ras(G12V)-expressing Barrett's cells resulted in high levels of mitochondrial phospho-STAT3 (Ser727) with little or no nuclear phospho-STAT3 (Tyr705), and the cells still formed tumors in immunodeficient mice. Thus tyrosine phosphorylation of STAT3 is not required for tumor formation in Ras-expressing Barrett's cells. We conclude that mitochondrial STAT3 (Ser727) can contribute to oncogenesis in Barrett's cells that express oncogenic Ras. These findings suggest that agents targeting STAT3 might be useful for chemoprevention in patients with Barrett's esophagus.

  3. Gene expression profiling to define the cell intrinsic role of the SKI proto-oncogene in hematopoiesis and myeloid neoplasms.

    PubMed

    Chalk, Alistair M; Liddicoat, Brian J J; Walkley, Carl R; Singbrant, Sofie

    2014-12-01

    The proto-oncogene SKI is highly expressed in human myeloid leukemia and also in murine hematopoietic stem cells. However, its operative relevance in these cells remains elusive. We have over-expressed SKI to define its intrinsic role in hematopoiesis and myeloid neoplasms, which resulted in a robust competitive advantage upon transplantation, a complete dominance of the stem and progenitor compartments, and a marked enhancement of myeloid differentiation at the expense of other lineages. Accordingly, enforced expression of SKI induced gene signatures associated with hematopoietic stem cells and myeloid differentiation. Here we provide detailed experimental methods and analysis for the gene expression profiling described in our recently published study of Singbrant et al. (2014) in Haematologica. Our data sets (available at http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE39457) provide a resource for exploring the underlying molecular mechanisms of the involvement of the proto-oncogene SKI in hematopoietic stem cell function and development of myeloid neoplasms.

  4. MicroRNA 10b promotes abnormal expression of the proto-oncogene c-Jun in metastatic breast cancer cells

    PubMed Central

    Knirsh, Revital; Ben-Dror, Iris; Modai, Shira; Shomron, Noam; Vardimon, Lily

    2016-01-01

    MicroRNAs have been shown to act as oncogenes or tumor suppressers via various cellular pathways. Specifically, in breast cancer, upregulation of miR-10b is positively associated with aggressiveness of tumors. However, the mechanism by which miR-10b contributes to cell malignancy is largely unknown. Here we show that at the receiving end of the miR-10b pathway is the proto-oncogene c-Jun, a transcription factor that plays a critical role in stimulation of cell proliferation and tumor progression. c-Jun is known to be translationally activated by loss of cell contacts or restructuring of the cytoskeleton. A comprehensive analysis of miRNA expression exhibited a significant increase in miR-10b expression. This was supported by analysis of breast cancer cells, which showed that loss of E-cadherin in metastatic cells is accompanied by elevation of miR-10b and interestingly, by a marked increase in accumulation of c-Jun. Silencing miR-10b in metastatic breast cancer cells leads to a decline in c-Jun expression, whereas overexpression of miR-10b in HaCaT cells is sufficient to elevate the accumulation of c-Jun. The increase in c-Jun protein accumulation in metastatic cells is not accompanied by an increase in c-Jun mRNA and is not dependent on MAPK activity. Knockdown and overexpression experiments revealed that the increase is mediated by NF1 and RhoC, downstream targets of miR-10b that affect cytoskeletal dynamics through the ROCK pathway. Overall, we show the ability of miR-10b to activate the expression of c-Jun through RhoC and NF1, which represents a novel pathway for promoting migration and invasion of human cancer cells. PMID:27494896

  5. Silencing of human papillomavirus (HPV) E6/E7 oncogene expression affects both the contents and the amounts of extracellular microvesicles released from HPV-positive cancer cells.

    PubMed

    Honegger, Anja; Leitz, Jenny; Bulkescher, Julia; Hoppe-Seyler, Karin; Hoppe-Seyler, Felix

    2013-10-01

    The human papillomavirus (HPV) E6/E7 oncogenes play a crucial role in the HPV-induced carcinogenesis. In this study, the authors investigated whether silencing of endogenous HPV E6/E7 expression may influence the contents or amounts of extracellular microvesicles (eMVs) released from HPV-positive cancer cells. It was found that eMVs secreted from HeLa cells are enriched for Survivin protein. RNA interference studies revealed that maintenance of both intracellular and microvesicular Survivin amounts was strongly dependent on continuous E6/E7 expression. This indicates that intracellular HPV activities are translated into visible alterations of protein contents in eMVs. Besides Survivin, eMVs from HeLa cells contain additional members of the inhibitor of apoptosis protein (IAP) family (XIAP, c-IAP1 and Livin). In contrast, no evidence for the presence of the HPV E6 and E7 oncoproteins in eMVs was obtained. Moreover, it was found that silencing of HPV E6/E7 expression led to a significant increase of exosomes-representing eMVs of endocytic origin-released from HeLa cells. This effect was associated with the reinduction of p53, stimulation of the p53 target genes TSAP6 and CHMP4C that can enhance exosome production and induction of senescence. Taken together, these results show that silencing of HPV E6/E7 oncogene expression profoundly affects both the composition and amounts of eMVs secreted by HPV-positive cancer cells. This indicates that HPVs can induce molecular signatures in eMVs that may affect intercellular communication and could be explored for diagnostic purposes.

  6. Suppression of the metastatic phenotype of a mouse skin carcinoma cell line independent of E-cadherin expression and correlated with reduced Ha-ras oncogene products.

    PubMed

    Caulín, C; López-Barcons, L; Gonzáles-Garrigues, M; Navarro, P; Lozano, E; Rodrigo, I; Gamallo, C; Cano, A; Fabra, A; Quintanilla, M

    1996-02-01

    The HaCa4 cell line, derived from a mouse skin carcinoma induced by Harvey murine sarcoma virus, is highly tumorigenic when injected into nude mice and produces multiple metastases in the lungs. HaCa4 cells express high levels of viral Ha-ras oncogene products, anomalously synthesize the embryonic/simple epithelial keratin K8, and have lost the expression of the cell-cell adhesion receptor E-cadherin (E-CD). E-CD(+) cell clones (E62 and E24), obtained by transfection of an exogenous E-CD cDNA into HaCa4 cells, had a decreased ability to migrate through type IV collagen matrices. However, the E-CD (+) E62 clone remained as metastatic as the parental cell line, whereas the E24 clone, which does not take up the exogenous cDNA but spontaneously switches on the endogenous E-CD gene, suppressed the metastatic phenotype although it maintained its tumorigenicity. E24 cells had fivefold to sixfold lower levels of viral Ha-ras mRNA and p21 protein than the other cell lines. In addition, they did not synthesize K8 but rather switched on keratin K19. The comparison of E-CD proteins synthesized by E62 and E24 cell lines revealed no structural or functional differences because both localized at cell-cell contacts and associated with alpha-catenin, beta-catenin, and plakoglobin. Furthermore, E-CD was still expressed in metastatic lung nodules produced by E62 cells. These results suggest that suppression of the metastatic phenotype in E24 cells occurs independently of E-CD expression and correlates with decreased levels of the oncogenic ras p21 protein.

  7. Localized adenocarcinoma of the lung: oncogene expression of erbB-2 and p53 in 150 patients.

    PubMed

    Harpole, D H; Marks, J R; Richards, W G; Herndon, J E; Sugarbaker, D J

    1995-06-01

    Historical information and pathological material from 150 consecutive patients with localized adenocarcinoma of the lung was collected to evaluate oncogene expression of erbB-2 and p53, and erbB-2 gene amplification. Pathological material after resection was reviewed to verify histological staging, and patient follow-up was complete in all cases for at least 68 months. Immunohistochemistry of erbB-2 (HER-2/neu) and p53 oncogene expression was performed on two separate paraffin tumor blocks for each patient with normal lung as control. Gene amplification of erbB-2 was measured after DNA extraction from 20-micrometer sections of erbB-2-positive and -negative tumors. All analyses were blinded and included Kaplan-Meier survival estimates with Cox proportional hazards regression modeling. Two adequate blocks of tumor and normal lung were available for 138 (92%) patients. Immunohistochemical identification of expression of p53 was observed in 49 (37%) patients and erbB-2 in 17 (13%) patients. DNA dot blot analyses were performed on 17 erbB-2-positive and 13 randomly selected erbB-2-negative tumors. There was 1 (6%) of 17 erbB-2-positve tumors with 4-fold erbB-2 gene amplification. Actual 5-year survival was 63% and actuarial 10-year survival was 59% for the entire population of 150 patients. Significant univariate predictors (P < 0.05) of cancer death were the presence of symptoms, tumor size >3 cm, poor differentiation, visceral pleural invasion, and p53 expression. Multivariate analysis associated symptoms and p53 expression as independent factors with decreased survival. Thus, this project examined p53 and erbB-2 expression in patients with localized adenocarcinoma and associated p53 status with survival. Multicenter collection of data should allow the development of a model of cancer recurrence in this most common lung cancer.

  8. A Global View of the Oncogenic Landscape in Nasopharyngeal Carcinoma: An Integrated Analysis at the Genetic and Expression Levels

    PubMed Central

    Hu, Chunfang; Wei, Wenbin; Chen, Xiaoyi; Woodman, Ciaran B.; Yao, Yunhong; Nicholls, John M.; Joab, Irène; Sihota, Sim K.; Shao, Jian-Yong; Derkaoui, K. Dalia; Amari, Aicha; Maloney, Stephanie L.; Bell, Andrew I.; Murray, Paul G.; Dawson, Christopher W.; Young, Lawrence S.; Arrand, John R.

    2012-01-01

    Previous studies have reported that the tumour cells of nasopharyngeal carcinoma (NPC) exhibit recurrent chromosome abnormalities. These genetic changes are broadly assumed to lead to changes in gene expression which are important for the pathogenesis of this tumour. However, this assumption has yet to be formally tested at a global level. Therefore a genome wide analysis of chromosome copy number and gene expression was performed in tumour cells micro-dissected from the same NPC biopsies. Cellular tumour suppressor and tumour-promoting genes (TSG, TPG) and Epstein-Barr Virus (EBV)-encoded oncogenes were examined. The EBV-encoded genome maintenance protein EBNA1, along with the putative oncogenes LMP1, LMP2 and BARF1 were expressed in the majority of NPCs that were analysed. Significant downregulation of expression in an average of 76 cellular TSGs per tumour was found, whilst a per-tumour average of 88 significantly upregulated, TPGs occurred. The expression of around 60% of putative TPGs and TSGs was both up-and down-regulated in different types of cancer, suggesting that the simplistic classification of genes as TSGs or TPGs may not be entirely appropriate and that the concept of context-dependent onco-suppressors may be more extensive than previously recognised. No significant enrichment of TPGs within regions of frequent genomic gain was seen but TSGs were significantly enriched within regions of frequent genomic loss. It is suggested that loss of the FHIT gene may be a driver of NPC tumourigenesis. Notwithstanding the association of TSGs with regions of genomic loss, on a gene by gene basis and excepting homozygous deletions and high-level amplification, there is very little correlation between chromosomal copy number aberrations and expression levels of TSGs and TPGs in NPC. PMID:22815911

  9. Expression of the human ETS-2 oncogene in normal fetal tissues and in the brain of a fetus with trisomy 21.

    PubMed

    Baffico, M; Perroni, L; Rasore-Quartino, A; Scartezzini, P

    1989-10-01

    The expression of the ETS-2 proto-oncogene, located on chromosome 21, in normal fetal tissues and in neural tissue of a fetus affected by Down syndrome has been investigated. The results show that the ETS-2 proto-oncogene is expressed in almost all the tissues examined and that it is transcribed at constant levels in neural tissue between the 13th and 24th weeks. ETS-2 expression appeared to be slightly increased in Down syndrome brain compared with that of normal controls of the same gestational age.

  10. Comparative transcriptomic analysis reveals the oncogenic fusion protein PAX3-FOXO1 globally alters mRNA and miRNA to enhance myoblast invasion

    PubMed Central

    Loupe, J M; Miller, P J; Bonner, B P; Maggi, E C; Vijayaraghavan, J; Crabtree, J S; Taylor, C M; Zabaleta, J; Hollenbach, A D

    2016-01-01

    Rhabdomyosarcoma, one of the most common childhood sarcomas, is comprised of two main subtypes, embryonal and alveolar (ARMS). ARMS, the more aggressive subtype, is primarily characterized by the t(2;13)(p35;p14) chromosomal translocation, which fuses two transcription factors, PAX3 and FOXO1 to generate the oncogenic fusion protein PAX3-FOXO1. Patients with PAX3-FOXO1-postitive tumors have a poor prognosis, in part due to the enhanced local invasive capacity of these cells, which leads to the increased metastatic potential for this tumor. Despite this knowledge, little is known about the role that the oncogenic fusion protein has in this increased invasive potential. In this report we use large-scale comparative transcriptomic analyses in physiologically relevant primary myoblasts to demonstrate that the presence of PAX3-FOXO1 is sufficient to alter the expression of 70 mRNA and 27 miRNA in a manner predicted to promote cellular invasion. In contrast the expression of PAX3 alters 60 mRNA and 23 miRNA in a manner predicted to inhibit invasion. We demonstrate that these alterations in mRNA and miRNA translate into changes in the invasive potential of primary myoblasts with PAX3-FOXO1 increasing invasion nearly 2-fold while PAX3 decreases invasion nearly 4-fold. Taken together, these results allow us to build off of previous reports and develop a more expansive molecular model by which the presence of PAX3-FOXO1 alters global gene regulatory networks to enhance the local invasiveness of cells. Further, the global nature of our observed changes highlights the fact that instead of focusing on a single-gene target, we must develop multi-faceted treatment regimens targeting multiple genes of a single oncogenic phenotype or multiple genes that target different oncogenic phenotypes for tumor progression. PMID:27454080

  11. Hypoxia induces H19 expression through direct and indirect Hif-1α activity, promoting oncogenic effects in glioblastoma

    PubMed Central

    Wu, Weining; Hu, Qi; Nie, Er; Yu, Tianfu; Wu, Youzhi; Zhi, Tongle; Jiang, Kuan; Shen, Feng; Wang, Yingyi; Zhang, Junxia; You, Yongping

    2017-01-01

    H19 expression is elevated in many human tumors including glioblastomas, suggesting an oncogenic role for the long noncoding RNA; yet the upregulation of H19 in glioblastomas remains unclear. Here we report that hypoxia significantly stimulated H19 expression in glioblastoma cell lines, which was related to hypoxia-inducible factors 1α (Hif-1α). Hif-1α promoted H19 expression in U87 and U251 cells. Meanwhile PTEN is an advantageous factor to affect H19 expression, through attenuating Hif-1α stability. Hif-1α also positively correlates with H19 in human glioblastoma samples depending on PTEN status. ChIP and luciferase reporter assays showed that Hif-1α induced H19 transcription through directly binding to the H19 promoter. Furthermore, Hif-1α upregulated specific protein 1 (SP1) expression in glioblastomas cells in vitro and in vivo, and SP1 also strongly interacted with the H19 promoter to promote H19 expression under hypoxia. We also showed that H19 acts as a molecular sponge that binds miR-181d, relieving inhibition of β-catenin expression. Therefore, H19 participates in hypoxia-driven migration and invasion in glioblastoma cells. In summary, our results uncover the mechanisms that stimulate H19 expression under hypoxia to promote malignant effects in glioblastomas and suggest H19 might be a promising therapeutic target. PMID:28327666

  12. Inhibition of carcinogen induced c-Ha-ras and c-fos proto-oncogenes expression by dietary curcumin

    PubMed Central

    Limtrakul, Porn-ngarm; Anuchapreeda, Songyot; Lipigorngoson, Suwiwek; Dunn, Floyd W

    2001-01-01

    Background We investigated the chemopreventive action of dietary curcumin on 7,12-dimethylbenz(a)anthracene (DMBA)-initiated and 12,0-tetradecanoylphorbol-13-acetate (TPA)-promoted skin tumor formation in Swiss albino mice. Curcumin, a yellow coloring matter isolated from roots of Curcuma longa Linn, is a phenolic compound possessing antioxidant, free radical scavenger, and antiinflammatory properties. It has been shown by previously reported work that TPA-induced skin tumors were inhibited by topical application of curcumin, and curcumin has been shown to inhibit a variety of biological activities of TPA. Topical application of curcumin was reported to inhibit TPA-induced c-fos, c-jun and c-myc gene expression in mouse skin. This paper reports the effects of orally administered curcumin, which was consumed as a dietary component at concentrations of 0.2 % or 1 %, in ad libitum feeding. Results Animals in which tumors had been initiated with DMBA and promoted with TPA experienced significantly fewer tumors and less tumor volume if they ingested either 0.2% or 1% curcumin diets. Also, the dietary consumption of curcumin resulted in a significantly decreased expression of ras and fos proto-oncogenes in the tumorous skin, as measured by enhanced chemiluminesence Western blotting detection system (Amersham). Conclusions Whereas earlier work demonstrated that topical application of curcumin to mouse skin inhibited TPA-induced expression of c-fos, c-jun and c-myc oncogenes, our results are the first to show that orally consumed curcumin significantly inhibited DMBA- and TPA-induced ras and fos gene expression in mouse skin. PMID:11231886

  13. The RON and MET oncogenes are co-expressed in human ovarian carcinomas and cooperate in activating invasiveness.

    PubMed

    Maggiora, Piera; Lorenzato, Annalisa; Fracchioli, Stefano; Costa, Barbara; Castagnaro, Massimo; Arisio, Riccardo; Katsaros, Dionyssios; Massobrio, Marco; Comoglio, Paolo M; Flavia Di Renzo, Maria

    2003-08-15

    RON is a member of the receptor tyrosine kinase gene family that includes the MET oncogene, whose germline mutations have been causally related to human tumorigenesis. In vitro, RON and MET receptors cross-talk, synergize in intracellular signaling, and cooperate in inducing morphogenic responses. Here we show that the RON and MET oncogenes were expressed in 55% and 56% of human ovarian carcinomas, respectively, and were significantly coexpressed in 42% (P < 0.001). In ovarian carcinoma samples and cell lines we did not find mutations in RON and MET gene kinase domain, nor coexpression of RON and MET receptor ligands (MSP and HGF, respectively). We show that motility and invasiveness of ovarian cancer cells coexpressing MET and RON receptors were elicited by HGF and, to a lesser extent, by MSP. More interestingly, invasion of both reconstituted basement membrane and collagen gel was greatly enhanced by the simultaneous addition of the two ligands. These data suggest that coexpression of the MET and RON receptors confer a selective advantage to ovarian cancer cells and might promote ovarian cancer progression.

  14. Epigenome Mapping Reveals Distinct Modes of Gene Regulation and Widespread Enhancer Reprogramming by the Oncogenic Fusion Protein EWS-FLI1

    PubMed Central

    Tomazou, Eleni M.; Sheffield, Nathan C.; Schmidl, Christian; Schuster, Michael; Schönegger, Andreas; Datlinger, Paul; Kubicek, Stefan; Bock, Christoph; Kovar, Heinrich

    2015-01-01

    Summary Transcription factor fusion proteins can transform cells by inducing global changes of the transcriptome, often creating a state of oncogene addiction. Here, we investigate the role of epigenetic mechanisms in this process, focusing on Ewing sarcoma cells that are dependent on the EWS-FLI1 fusion protein. We established reference epigenome maps comprising DNA methylation, seven histone marks, open chromatin states, and RNA levels, and we analyzed the epigenome dynamics upon downregulation of the driving oncogene. Reduced EWS-FLI1 expression led to widespread epigenetic changes in promoters, enhancers, and super-enhancers, and we identified histone H3K27 acetylation as the most strongly affected mark. Clustering of epigenetic promoter signatures defined classes of EWS-FLI1-regulated genes that responded differently to low-dose treatment with histone deacetylase inhibitors. Furthermore, we observed strong and opposing enrichment patterns for E2F and AP-1 among EWS-FLI1-correlated and anticorrelated genes. Our data describe extensive genome-wide rewiring of epigenetic cell states driven by an oncogenic fusion protein. PMID:25704812

  15. mTORC1 upregulation via ERK-dependent gene expression change confers intrinsic resistance to MEK inhibitors in oncogenic KRas-mutant cancer cells.

    PubMed

    Komatsu, N; Fujita, Y; Matsuda, M; Aoki, K

    2015-11-05

    Cancer cells harboring oncogenic BRaf mutants, but not oncogenic KRas mutants, are sensitive to MEK inhibitors (MEKi). The mechanism underlying the intrinsic resistance to MEKi in KRas-mutant cells is under intensive investigation. Here, we pursued this mechanism by live imaging of extracellular signal-regulated kinases (ERK) and mammalian target of rapamycin complex 1 (mTORC1) activities in oncogenic KRas or BRaf-mutant cancer cells. We established eight cancer cell lines expressing Förster resonance energy transfer (FRET) biosensors for ERK activity and S6K activity, which was used as a surrogate marker for mTORC1 activity. Under increasing concentrations of MEKi, ERK activity correlated linearly with the cell growth rate in BRaf-mutant cancer cells, but not KRas-mutant cancer cells. The administration of PI3K inhibitors resulted in a linear correlation between ERK activity and cell growth rate in KRas-mutant cancer cells. Intriguingly, mTORC1 activity was correlated linearly with the cell growth rate in both BRaf-mutant cancer cells and KRas-mutant cancer cells. These observations suggested that mTORC1 activity had a pivotal role in cell growth and that the mTORC1 activity was maintained primarily by the ERK pathway in BRaf-mutant cancer cells and by both the ERK and PI3K pathways in KRas-mutant cancer cells. FRET imaging revealed that MEKi inhibited mTORC1 activity with slow kinetics, implying transcriptional control of mTORC1 activity by ERK. In agreement with this observation, MEKi induced the expression of negative regulators of mTORC1, including TSC1, TSC2 and Deptor, which occurred more significantly in BRaf-mutant cells than in KRas-mutant cells. These findings suggested that the suppression of mTORC1 activity and induction of negative regulators of mTORC1 in cancer cells treated for at least 1 day could be used as surrogate markers for the MEKi sensitivity of cancer cells.

  16. A Novel Model of SCID-X1 Reconstitution Reveals Predisposition to Retrovirus-induced Lymphoma but No Evidence of γC Gene Oncogenicity.

    PubMed

    Scobie, Linda; Hector, Ralph D; Grant, Louise; Bell, Margaret; Nielsen, Anne A; Meikle, Sharon; Philbey, Adrain; Thrasher, Adrain J; Cameron, Ewan R; Blyth, Karen; Neil, James C

    2009-06-01

    The emergence of leukemia following gene transfer to restore common cytokine receptor γ chain (γC) function in X-linked severe combined immunodeficiency (SCID-X1) has raised important questions with respect to gene therapy safety. To explore the risk factors involved, we tested the oncogenic potential of human γC in new strains of transgenic mice expressing the gene under the control of the CD2 promoter and locus control region (LCR). These mice demonstrated mildly perturbed T-cell development, with an increased proportion of thymic CD8 cells, but showed no predisposition to tumor development even on highly tumor prone backgrounds or after γ-retrovirus infection. The human CD2-γC transgene rescued T and B-cell development in γC(-/-) mice but with an age-related delay, mimicking postnatal reconstitution in SCID-X1 gene therapy subjects. However, we noted that γC(-/-) mice are acutely susceptible to murine leukemia virus (MLV) leukemogenesis, and that this trait was not corrected by the γC transgene. We conclude that the SCID-X1 phenotype can be corrected safely by stable ectopic expression of γC and that the transgene is not significantly oncogenic when expressed in this context. However, an underlying predisposition conferred by the SCID-X1 background appears to collaborate with insertional mutagenesis to increase the risk of tumor development.

  17. A novel model of SCID-X1 reconstitution reveals predisposition to retrovirus-induced lymphoma but no evidence of gammaC gene oncogenicity.

    PubMed

    Scobie, Linda; Hector, Ralph D; Grant, Louise; Bell, Margaret; Nielsen, Anne A; Meikle, Sharon; Philbey, Adrian; Philbey, Adrain; Thrasher, Adrian J; Thrasher, Adrain J; Cameron, Ewan R; Blyth, Karen; Neil, James C

    2009-06-01

    The emergence of leukemia following gene transfer to restore common cytokine receptor gamma chain (gammaC) function in X-linked severe combined immunodeficiency (SCID-X1) has raised important questions with respect to gene therapy safety. To explore the risk factors involved, we tested the oncogenic potential of human gammaC in new strains of transgenic mice expressing the gene under the control of the CD2 promoter and locus control region (LCR). These mice demonstrated mildly perturbed T-cell development, with an increased proportion of thymic CD8 cells, but showed no predisposition to tumor development even on highly tumor prone backgrounds or after gamma-retrovirus infection. The human CD2-gammaC transgene rescued T and B-cell development in gammaC(-/-) mice but with an age-related delay, mimicking postnatal reconstitution in SCID-X1 gene therapy subjects. However, we noted that gammaC(-/-) mice are acutely susceptible to murine leukemia virus (MLV) leukemogenesis, and that this trait was not corrected by the gammaC transgene. We conclude that the SCID-X1 phenotype can be corrected safely by stable ectopic expression of gammaC and that the transgene is not significantly oncogenic when expressed in this context. However, an underlying predisposition conferred by the SCID-X1 background appears to collaborate with insertional mutagenesis to increase the risk of tumor development.

  18. Aberrant microRNA Expression Likely Controls RAS Oncogene Activation During Malignant Transformation of Human Prostate Epithelial and Stem Cells by Arsenic

    PubMed Central

    Ngalame, Ntube N. O.; Tokar, Erik J.; Person, Rachel J.; Xu, Yuanyuan; Waalkes, Michael P.

    2014-01-01

    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. PMID:24431212

  19. Transient expression of Bcl6 is sufficient for oncogenic function and induction of mature B-cell lymphoma.

    PubMed

    Green, Michael R; Vicente-Dueñas, Carolina; Romero-Camarero, Isabel; Long Liu, Chih; Dai, Bo; González-Herrero, Inés; García-Ramírez, Idoia; Alonso-Escudero, Esther; Iqbal, Javeed; Chan, Wing C; Campos-Sanchez, Elena; Orfao, Alberto; Pintado, Belén; Flores, Teresa; Blanco, Oscar; Jiménez, Rafael; Martínez-Climent, Jose Angel; Criado, Francisco Javier García; Cenador, María Begoña García; Zhao, Shuchun; Natkunam, Yasodha; Lossos, Izidore S; Majeti, Ravindra; Melnick, Ari; Cobaleda, César; Alizadeh, Ash A; Sánchez-García, Isidro

    2014-06-02

    Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoma and can be separated into two subtypes based upon molecular features with similarities to germinal centre B-cells (GCB-like) or activated B-cells (ABC-like). Here we identify gain of 3q27.2 as being significantly associated with adverse outcome in DLBCL and linked with the ABC-like subtype. This lesion includes the BCL6 oncogene, but does not alter BCL6 transcript levels or target-gene repression. Separately, we identify expression of BCL6 in a subset of human haematopoietic stem/progenitor cells (HSPCs). We therefore hypothesize that BCL6 may act by 'hit-and-run' oncogenesis. We model this hit-and-run mechanism by transiently expressing Bcl6 within murine HSPCs, and find that it causes mature B-cell lymphomas that lack Bcl6 expression and target-gene repression, are transcriptionally similar to post-GCB cells, and show epigenetic changes that are conserved from HSPCs to mature B-cells. Together, these results suggest that BCL6 may function in a 'hit-and-run' role in lymphomagenesis.

  20. Xenopus myc proto-oncogene during development: expression as a stable maternal mRNA uncoupled from cell division.

    PubMed Central

    Taylor, M V; Gusse, M; Evan, G I; Dathan, N; Mechali, M

    1986-01-01

    A Xenopus cDNA clone highly homologous to the proto-oncogene c-myc has been isolated and used to derive a homologous probe to study myc expression during embryonic development. Myc RNA is identified as a member of the class of maternal mRNAs expressed before fertilisation. It is highly accumulated from early oogenesis and an unfertilised egg contains 8 pg, about 10(5)-fold the myc content of proliferative somatic cells. After fertilisation a post-transcriptional regulation of the gene is induced and the accumulated myc RNA is degraded (t1/2 = 4 h 20 min) to reach a level at gastrula of 10 transcripts per cell; a value maintained during subsequent embryonic development. The Xenopus myc protein has also been identified by both myc-specific antibodies and hybrid selection experiments. Translation in vitro of Xenopus myc RNA shows that it encodes a 62-kd protein which is also recognised by myc antibodies in oocyte extracts. This protein is accumulated in late oogenesis. The results indicate an unusual uncoupling of myc expression and cell proliferation linked to a stabilisation of the RNA product. Images Fig. 2. Fig. 3. Fig. 4. Fig. 6. Fig. 7. Fig. 8. PMID:3549280

  1. Transient expression of Bcl6 is sufficient for oncogenic function and induction of mature B-cell lymphoma

    PubMed Central

    Green, Michael R; Vicente-Dueñas, Carolina; Romero-Camarero, Isabel; Liu, Chih Long; Dai, Bo; González-Herrero, Inés; García-Ramírez, Idoia; Alonso-Escudero, Esther; Iqbal, Javeed; Chan, Wing C; Campos-Sanchez, Elena; Orfao, Alberto; Pintado, Belén; Flores, Teresa; Blanco, Oscar; Jiménez, Rafael; Martínez-Climent, Jose Angel; Criado, Francisco Javier García; Cenador, María Begoña García; Zhao, Shuchun; Natkunam, Yasodha; Lossos, Izidore S; Majeti, Ravindra; Melnick, Ari; Cobaleda, César; Alizadeh, Ash A.; Sánchez-García, Isidro

    2015-01-01

    Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoma and can be separated into two subtypes based upon molecular features with similarities to germinal center B-cells (GCB-like) or activated B-cells (ABC-like). Here we identify gain of 3q27.2 as being significantly associated with adverse outcome in DLBCL and linked with the ABC-like subtype. This lesion includes the BCL6 oncogene, but does not alter BCL6 transcript levels or target-gene repression. Separately, we identify expression of BCL6 in a subset of human hematopoietic stem/progenitor cells (HSPCs). We therefore hypothesize that BCL6 may act by hit-and-run oncogenesis. We model this by transiently expressing Bcl6 within murine HSPCs, and find it causes mature B-cell lymphomas that lack Bcl6 expression and target-gene repression, are transcriptionally similar to post-GCB cells, and show epigenetic changes that are conserved from HSPCs to mature B-cells. Together these results suggest that Bcl6 may function in a hit-and-run role in lymphomagenesis. PMID:24887457

  2. Control of PD-L1 Expression by Oncogenic Activation of the AKT-mTOR Pathway in Non-Small Cell Lung Cancer.

    PubMed

    Lastwika, Kristin J; Wilson, Willie; Li, Qing Kay; Norris, Jeffrey; Xu, Haiying; Ghazarian, Sharon R; Kitagawa, Hiroshi; Kawabata, Shigeru; Taube, Janis M; Yao, Sheng; Liu, Linda N; Gills, Joell J; Dennis, Phillip A

    2016-01-15

    Alterations in EGFR, KRAS, and ALK are oncogenic drivers in lung cancer, but how oncogenic signaling influences immunity in the tumor microenvironment is just beginning to be understood. Immunosuppression likely contributes to lung cancer, because drugs that inhibit immune checkpoints like PD-1 and PD-L1 have clinical benefit. Here, we show that activation of the AKT-mTOR pathway tightly regulates PD-L1 expression in vitro and in vivo. Both oncogenic and IFNγ-mediated induction of PD-L1 was dependent on mTOR. In human lung adenocarcinomas and squamous cell carcinomas, membranous expression of PD-L1 was significantly associated with mTOR activation. These data suggest that oncogenic activation of the AKT-mTOR pathway promotes immune escape by driving expression of PD-L1, which was confirmed in syngeneic and genetically engineered mouse models of lung cancer where an mTOR inhibitor combined with a PD-1 antibody decreased tumor growth, increased tumor-infiltrating T cells, and decreased regulatory T cells.

  3. Expression of oncogenic K-ras from its endogenous promoter leads to a partial block of erythroid differentiation and hyperactivation of cytokine-dependent signaling pathways.

    PubMed

    Zhang, Jing; Liu, Yangang; Beard, Caroline; Tuveson, David A; Jaenisch, Rudolf; Jacks, Tyler E; Lodish, Harvey F

    2007-06-15

    When overexpressed in primary erythroid progenitors, oncogenic Ras leads to the constitutive activation of its downstream signaling pathways, severe block of terminal erythroid differentiation, and cytokine-independent growth of primary erythroid progenitors. However, whether high-level expression of oncogenic Ras is required for these phenotypes is unknown. To address this issue, we expressed oncogenic K-ras (K-ras(G12D)) from its endogenous promoter using a tetracycline-inducible system. We show that endogenous K-ras(G12D) leads to a partial block of terminal erythroid differentiation in vivo. In contrast to results obtained when oncogenic Ras was overexpressed from retroviral vectors, endogenous levels of K-ras(G12D) fail to constitutively activate but rather hyperactivate cytokine-dependent signaling pathways, including Stat5, Akt, and p44/42 MAPK, in primary erythroid progenitors. This explains previous observations that hematopoietic progenitors expressing endogenous K-ras(G12D) display hypersensitivity to cytokine stimulation in various colony assays. Our results support efforts to modulate Ras signaling for treating hematopoietic malignancies.

  4. Current Protocols in Mouse Biology Tissue-specific regulation of oncogene expression using Cre-inducible ROSA26 knock-in transgenic mice

    PubMed Central

    Carofino, Brandi L.; Justice, Monica J.

    2015-01-01

    Cre-inducible mouse models are often utilized for the spatial and temporal expression of oncogenes. With the wide number of Cre recombinase lines available, inducible transgenesis represents a tractable approach to achieve discrete oncogene expression. Here, we describe a protocol for targeting Cre-inducible genes using a loxP-STOP-loxP approach to the ubiquitously expressed ROSA26 locus. Gene targeting provides several advantages over standard transgenic techniques, including a known site of integration and previously characterized pattern of expression. Historically, an inherent instability of ROSA26 targeting vectors has hampered the efficiency of developing ROSA26 knock-in lines. In this protocol, we provide individual steps for utilizing Gateway recombination for cloning, and detailed instructions for screening targeted ES cell clones. By following this protocol, one can achieve germline transmission of a ROSA26 knock-in line within several months. PMID:26069083

  5. The relationship between expressions of N-myc and c-myc oncogenes in neuroblastoma: an in situ hybridization and immunocytochemical study.

    PubMed

    Zhe, X; Chen, J; Liu, T; Zhang, L; Li, P; Wang, D

    1999-06-01

    N-myc gene amplification is the most characteristic feature of neuroblastoma. c-myc oncogene, another member of myc gene family, plays an important role in cell proliferation and differentiation. Both of them may contribute to tumorigenesis of neuroblastoma. In this study we use the in situ hybridization and immunocytochemical methods to test the frequencies of N-myc and c-myc expressions in 20 cases of human neuroblastoma at mRNA and protein levels. The positive rates of the expression of N-myc are 90% and 100% detected by in situ hybridization and immunocytochemical methods respectively. The positive rates of c-myc are 80% and 85% respectively. Sixty percent of the 20 specimens tested by in situ hybridization and 55% by immunocytochemistry show an inverse relationship between the expressions of these two oncogenes and this may indicate that there are different gene expression controlling mechanisms in different cases.

  6. Oncogenic transformation of mesenchymal stem cells decreases Nrf2 expression favoring in vivo tumor growth and poorer survival

    PubMed Central

    2014-01-01

    Background The transcription factor Nrf2 is a key regulator of the cellular antioxidant response, and its activation by chemoprotective agents has been proposed as a potential strategy to prevent cancer. However, activating mutations in the Nrf2 pathway have been found to promote tumorigenesis in certain models. Therefore, the role of Nrf2 in cancer remains contentious. Methods We employed a well-characterized model of stepwise human mesenchymal stem cell (MSC) transformation and breast cancer cell lines to investigate oxidative stress and the role of Nrf2 during tumorigenesis. The Nrf2 pathway was studied by microarray analyses, qRT-PCR, and western-blotting. To assess the contribution of Nrf2 to transformation, we established tumor xenografts with transformed MSC expressing Nrf2 (n = 6 mice per group). Expression and survival data for Nrf2 in different cancers were obtained from GEO and TCGA databases. All statistical tests were two-sided. Results We found an accumulation of reactive oxygen species during MSC transformation that correlated with the transcriptional down-regulation of antioxidants and Nrf2-downstream genes. Nrf2 was repressed in transformed MSC and in breast cancer cells via oncogene-induced activation of the RAS/RAF/ERK pathway. Furthermore, restoration of Nrf2 function in transformed cells decreased reactive oxygen species and impaired in vivo tumor growth (P = 0.001) by mechanisms that included sensitization to apoptosis, and a decreased hypoxic/angiogenic response through HIF-1α destabilization and VEGFA repression. Microarray analyses showed down-regulation of Nrf2 in a panel of human tumors and, strikingly, low Nrf2 expression correlated with poorer survival in patients with melanoma (P = 0.0341), kidney (P = 0.0203) and prostate (P = 0.00279) cancers. Conclusions Our data indicate that oncogene-induced Nrf2 repression is an adaptive response for certain cancers to acquire a pro-oxidant state that favors cell survival and

  7. Regulation of proto-oncogene expression in adult and developing lungs.

    PubMed Central

    Molinar-Rode, R; Smeyne, R J; Curran, T; Morgan, J I

    1993-01-01

    Activation of immediate-early gene expression has been associated with mitogenesis, differentiation, nerve cell depolarization, and recently, terminal differentiation processes and programmed cell death. Previous evidence also suggested that immediate-early genes play a role in the physiology of the lungs (J. I. Morgan, D. R. Cohen, J. L. Hempstead, and T. Curran, Science 237:192-197, 1987). Therefore, we analyzed c-fos expression in adult and developing lung tissues. Seizures elicited by chemoconvulsants induced expression of mRNA for c-fos, c-jun, and junB and Fos-like immunoreactivity in lung tissue. The use of pharmacological antagonists and adrenalectomy indicated that this increased expression was neurogenic. Interestingly, by using a fos-lacZ transgenic mouse, it was shown that Fos-LacZ expression in response to seizure occurred preferentially in clusters of epithelial cells at the poles of the bronchioles. This was the same location of Fos-LacZ expression detected during early lung development. These data imply that pharmacological induction of immediate-early gene expression in adult mice recapitulates an embryological program of gene expression. Images PMID:8497249

  8. Inhibition of PTEN Gene Expression by Oncogenic miR-23b-3p in Renal Cancer

    PubMed Central

    Zaman, Mohd Saif; Thamminana, Sobha; Shahryari, Varahram; Chiyomaru, Takeshi; Deng, Guoren; Saini, Sharanjot; Majid, Shahana; Fukuhara, Shinichiro; Chang, Inik; Arora, Sumit; Hirata, Hiroshi; Ueno, Koji; Singh, Kamaldeep; Tanaka, Yuichiro; Dahiya, Rajvir

    2012-01-01

    Background miR-23b is located on chromosome number 9 and plays different roles in different organs especially with regards to cancer development. However, the functional significance of miR-23b-3p in renal cell carcinoma (RCC) has not been reported. Methods and Results We measured miR-23b-3p levels in 29 pairs of renal cell carcinoma and their normal matched tissues using real-time PCR. The expression level of miR-23b-3p was correlated with the 5 year survival rate of renal cancer patients. In 15 cases (52%), miR-23b-3p expression was found to be high. All patients with moderate to low miR-23b-3p expression survived 5 years, while those with high miR-23b-3p expression, only 50% survived. After knocking down miRNA-23b-3p expression in RCC cell lines, there was an induction of apoptosis and reduced invasive capabilities. MiR-23b-3p was shown to directly target PTEN gene through 3′UTR reporter assays. Inhibition of miR-23b-3p induces PTEN gene expression with a concomitant reduction in PI3-kinase, total Akt and IL-32. Immunohistochemistry showed the lack of PTEN protein expression in cancerous regions of tissue samples where the expression of miR-23b-3p was high. We studied the in vitro effects of the dietary chemo preventive agent genistein on miR-23b-3p expression and found that it inhibited expression of miR-23b-3p in RCC cell lines. Conclusions The current study shows that miR-23b-3p is an oncogenic miRNA and inhibits PTEN tumor suppressor gene in RCC. Therefore, inhibition of miR-23b-3p may be a useful therapeutic target for the treatment of renal cell carcinoma. PMID:23189187

  9. Expression of MALT1 oncogene in hematopoietic stem/progenitor cells recapitulates the pathogenesis of human lymphoma in mice

    PubMed Central

    Vicente-Dueñas, Carolina; Fontán, Lorena; Gonzalez-Herrero, Ines; Romero-Camarero, Isabel; Segura, Victor; Aznar, M. Angela; Alonso-Escudero, Esther; Campos-Sanchez, Elena; Ruiz-Roca, Lucía; Barajas-Diego, Marcos; Sagardoy, Ainara; Martinez-Ferrandis, Jose I.; Abollo-Jimenez, Fernando; Bertolo, Cristina; Peñuelas, Ivan; Garcia-Criado, Francisco J.; García-Cenador, María B.; Tousseyn, Thomas; Agirre, Xabier; Prosper, Felipe; Garcia-Bragado, Federico; McPhail, Ellen D.; Lossos, Izidore S.; Du, Ming-Qing; Flores, Teresa; Hernandez-Rivas, Jesus M.; Gonzalez, Marcos; Salar, Antonio; Bellosillo, Beatriz; Conde, Eulogio; Siebert, Reiner; Sagaert, Xavier; Cobaleda, Cesar; Sanchez-Garcia, Isidro; Martinez-Climent, Jose A.

    2012-01-01

    Chromosomal translocations involving the MALT1 gene are hallmarks of mucosa-associated lymphoid tissue (MALT) lymphoma. To date, targeting these translocations to mouse B cells has failed to reproduce human disease. Here, we induced MALT1 expression in mouse Sca1+Lin− hematopoietic stem/progenitor cells, which showed NF-κB activation and early lymphoid priming, being selectively skewed toward B-cell differentiation. These cells accumulated in extranodal tissues and gave rise to clonal tumors recapitulating the principal clinical, biological, and molecular genetic features of MALT lymphoma. Deletion of p53 gene accelerated tumor onset and induced transformation of MALT lymphoma to activated B-cell diffuse large-cell lymphoma (ABC-DLBCL). Treatment of MALT1-induced lymphomas with a specific inhibitor of MALT1 proteolytic activity decreased cell viability, indicating that endogenous Malt1 signaling was required for tumor cell survival. Our study shows that human-like lymphomas can be modeled in mice by targeting MALT1 expression to hematopoietic stem/progenitor cells, demonstrating the oncogenic role of MALT1 in lymphomagenesis. Furthermore, this work establishes a molecular link between MALT lymphoma and ABC-DLBCL, and provides mouse models to test MALT1 inhibitors. Finally, our results suggest that hematopoietic stem/progenitor cells may be involved in the pathogenesis of human mature B-cell lymphomas. PMID:22689981

  10. Expression and function of the novel proto-oncogene PBF in thyroid cancer: a new target for augmenting radioiodine uptake.

    PubMed

    Smith, Vicki E; Franklyn, Jayne A; McCabe, Christopher J

    2011-08-01

    Pituitary tumor-transforming gene (PTTG)-binding factor (PBF; PTTG1IP) was initially identified through its interaction with the human securin, PTTG. Like PTTG, PBF is upregulated in multiple endocrine tumours including thyroid cancer. PBF is believed to induce the translocation of PTTG into the cell nucleus where it can drive tumourigenesis via a number of different mechanisms. However, an independent transforming ability has been demonstrated both in vitro and in vivo, suggesting that PBF is itself a proto-oncogene. Studied in only a limited number of publications to date, PBF is emerging as a protein with a growing repertoire of roles. Recent data suggest that PBF possesses a complex multifunctionality in an increasing number of tumour settings. For example, PBF is upregulated by oestrogen and mediates oestrogen-stimulated cell invasion in breast cancer cells. In addition to a possible role in the induction of thyroid tumourigenesis, PBF overexpression in thyroid cancers inhibits iodide uptake. PBF has been shown to repress sodium iodide symporter (NIS) activity by transcriptional regulation of NIS expression through the human NIS upstream enhancer and further inhibits iodide uptake via a post-translational mechanism of NIS governing subcellular localisation. This review discusses the current data describing PBF expression and function in thyroid cancer and highlights PBF as a novel target for improving radioiodine uptake and thus prognosis in thyroid cancer.

  11. Expression of MALT1 oncogene in hematopoietic stem/progenitor cells recapitulates the pathogenesis of human lymphoma in mice.

    PubMed

    Vicente-Dueñas, Carolina; Fontán, Lorena; Gonzalez-Herrero, Ines; Romero-Camarero, Isabel; Segura, Victor; Aznar, M Angela; Alonso-Escudero, Esther; Campos-Sanchez, Elena; Ruiz-Roca, Lucía; Barajas-Diego, Marcos; Sagardoy, Ainara; Martinez-Ferrandis, Jose I; Abollo-Jimenez, Fernando; Bertolo, Cristina; Peñuelas, Ivan; Garcia-Criado, Francisco J; García-Cenador, María B; Tousseyn, Thomas; Agirre, Xabier; Prosper, Felipe; Garcia-Bragado, Federico; McPhail, Ellen D; Lossos, Izidore S; Du, Ming-Qing; Flores, Teresa; Hernandez-Rivas, Jesus M; Gonzalez, Marcos; Salar, Antonio; Bellosillo, Beatriz; Conde, Eulogio; Siebert, Reiner; Sagaert, Xavier; Cobaleda, Cesar; Sanchez-Garcia, Isidro; Martinez-Climent, Jose A

    2012-06-26

    Chromosomal translocations involving the MALT1 gene are hallmarks of mucosa-associated lymphoid tissue (MALT) lymphoma. To date, targeting these translocations to mouse B cells has failed to reproduce human disease. Here, we induced MALT1 expression in mouse Sca1(+)Lin(-) hematopoietic stem/progenitor cells, which showed NF-κB activation and early lymphoid priming, being selectively skewed toward B-cell differentiation. These cells accumulated in extranodal tissues and gave rise to clonal tumors recapitulating the principal clinical, biological, and molecular genetic features of MALT lymphoma. Deletion of p53 gene accelerated tumor onset and induced transformation of MALT lymphoma to activated B-cell diffuse large-cell lymphoma (ABC-DLBCL). Treatment of MALT1-induced lymphomas with a specific inhibitor of MALT1 proteolytic activity decreased cell viability, indicating that endogenous Malt1 signaling was required for tumor cell survival. Our study shows that human-like lymphomas can be modeled in mice by targeting MALT1 expression to hematopoietic stem/progenitor cells, demonstrating the oncogenic role of MALT1 in lymphomagenesis. Furthermore, this work establishes a molecular link between MALT lymphoma and ABC-DLBCL, and provides mouse models to test MALT1 inhibitors. Finally, our results suggest that hematopoietic stem/progenitor cells may be involved in the pathogenesis of human mature B-cell lymphomas.

  12. Stat3 induces oncogenic Skp2 expression in human cervical carcinoma cells

    SciTech Connect

    Huang, Hanhui; Zhao, Wenrong; Yang, Dan

    2012-02-03

    Highlights: Black-Right-Pointing-Pointer Upregulation of Skp2 by IL-6 or Stat3 activation. Black-Right-Pointing-Pointer Stat3 activates Skp2 expression through bound to its promoter region. Black-Right-Pointing-Pointer Stat3 activates Skp2 expression through recruitment of P300. Black-Right-Pointing-Pointer Stat3 activation decreases the P27 stability. -- Abstract: Dysregulated Skp2 function promotes cell proliferation, which is consistent with observations of Skp2 over-expression in many types of human cancers, including cervical carcinoma (CC). However, the molecular mechanisms underlying elevated Skp2 expression have not been fully explored. Interleukin-6 (IL-6) induced Stat3 activation is viewed as crucial for multiple tumor growth and metastasis. Here, we demonstrate that Skp2 is a direct transcriptional target of Stat3 in the human cervical carcinoma cells. Our data show that IL-6 administration or transfection of a constitutively activated Stat3 in HeLa cells activates Skp2 mRNA transcription. Using luciferase reporter and ChIP assays, we show that Stat3 binds to the promoter region of Skp2 and promotes its activity through recruiting P300. As a result of the increase of Skp2 expression, endogenous p27 protein levels are markedly decreased. Thus, our results suggest a previously unknown Stat3-Skp2 molecular network controlling cervical carcinoma development.

  13. NANOG upregulates c-Jun oncogene expression through binding the c-Jun promoter.

    PubMed

    Lin, Yanli; Xiong, Fuyin; Zhou, Yanrong; Wu, Xiaojie; Liu, Fang; Xue, Shiwei; Chen, Hongxing

    2015-11-01

    NANOG plays important roles in neoplastic processes. However, the molecular mechanism of NANOG in tumorigenesis remains to be elucidated. In this report, we demonstrated that forced expression of NANOG in 293 cells and cancer cells led to increased c-Jun expression, whereas downregulation of endogenous NANOG significantly reduced c-Jun expression in cancer cells. Dual luciferase reporter assays demonstrated that NANOG binds the c-Jun proximal promoter and transactivates the c-Jun gene. An ATTA consensus motif between the -160 and -268 region of the c-Jun promoter was identified as the NANOG-responsive element. Electromobility shift assay and chromatin immunoprecipitation results confirmed the direct binding of NANOG protein to the c-Jun promoter in vitro and in vivo. NANOG directly bound c-Jun protein as shown by GST pulldown and immunoprecipitation assays. Taking these findings together, we conclude that c-Jun is a direct target gene of NANOG and that c-Jun protein may be a novel co-activator of NANOG in cancer cells. We suggest the possibility that NANOG may play a significant role in carcinogenesis via its activation of c-Jun expression.

  14. Loss of Dependence on Continued Expression of the Human Papillomavirus 16 E7 Oncogene in Cervical Cancers and Precancerous Lesions Arising in Fanconi Anemia Pathway-Deficient Mice

    PubMed Central

    Park, Soyeong; Park, Jung Wook; Pitot, Henry C.

    2016-01-01

    ABSTRACT   Fanconi anemia (FA) is a rare genetic disorder caused by defects in DNA damage repair. FA patients often develop squamous cell carcinoma (SCC) at sites where high-risk human papillomaviruses (HPVs) are known to cause cancer, including the cervix. However, SCCs found in human FA patients are often HPV negative, even though the majority of female FA patients with anogenital cancers had preexisting HPV-positive dysplasia. We hypothesize that HPVs contribute to the development of SCCs in FA patients but that the continued expression of HPV oncogenes is not required for the maintenance of the cancer state because FA deficiency leads to an accumulation of mutations in cellular genes that render the cancer no longer dependent upon viral oncogenes. We tested this hypothesis, making use of Bi-L E7 transgenic mice in which we temporally controlled expression of HPV16 E7, the dominant viral oncogene in HPV-associated cancers. As seen before, the persistence of cervical neoplastic disease was highly dependent upon the continued expression of HPV16 E7 in FA-sufficient mice. However, in mice with FA deficiency, cervical cancers persisted in a large fraction of the mice after HPV16 E7 expression was turned off, indicating that these cancers had escaped from their dependency on E7. Furthermore, the severity of precancerous lesions also failed to be reduced significantly in the mice with FA deficiency upon turning off expression of E7. These findings confirm our hypothesis and may explain the fact that, while FA patients have a high frequency of infections by HPVs and HPV-induced precancerous lesions, the cancers are frequently HPV negative. Importance   Fanconi anemia (FA) patients are at high risk for developing squamous cell carcinoma (SCC) at sites where high-risk human papillomaviruses (HPVs) frequently cause cancer. Yet these SCCs are often HPV negative. FA patients have a genetic defect in their capacity to repair damaged DNA. HPV oncogenes cause an

  15. Zebra fish myc family and max genes: differential expression and oncogenic activity throughout vertebrate evolution.

    PubMed Central

    Schreiber-Agus, N; Horner, J; Torres, R; Chiu, F C; DePinho, R A

    1993-01-01

    To gain insight into the role of Myc family oncoproteins and their associated protein Max in vertebrate growth and development, we sought to identify homologs in the zebra fish (Brachydanio rerio). A combination of a polymerase chain reaction-based cloning strategy and low-stringency hybridization screening allowed for the isolation of zebra fish c-, N-, and L-myc and max genes; subsequent structural characterization showed a high degree of conservation in regions that encode motifs of known functional significance. On the functional level, zebra fish Max, like its mammalian counterpart, served to suppress the transformation activity of mouse c-Myc in rat embryo fibroblasts. In addition, the zebra fish c-myc gene proved capable of cooperating with an activated H-ras to effect the malignant transformation of mammalian cells, albeit with diminished potency compared with mouse c-myc. With respect to their roles in normal developing tissues, the differential temporal and spatial patterns of steady-state mRNA expression observed for each zebra fish myc family member suggest unique functions for L-myc in early embryogenesis, for N-myc in establishment and growth of early organ systems, and for c-myc in increasingly differentiated tissues. Furthermore, significant alterations in the steady-state expression of zebra fish myc family genes concomitant with relatively constant max expression support the emerging model of regulation of Myc function in cellular growth and differentiation. Images PMID:8474440

  16. An In Silico Study of the Differential Effect of Oxidation on Two Biologically Relevant G-Quadruplexes: Possible Implications in Oncogene Expression

    PubMed Central

    Stebbeds, William J. D.; Lunec, Joseph; Larcombe, Lee D.

    2012-01-01

    G-quadruplex structures, formed from guanine rich sequences, have previously been shown to be involved in various physiological processes including cancer-related gene expression. Furthermore, G-quadruplexes have been found in several oncogene promoter regions, and have been shown to play a role in the regulation of gene expression. The mutagenic properties of oxidative stress on DNA have been widely studied, as has the association with carcinogenesis. Guanine is the most susceptible nucleotide to oxidation, and as such, G-rich sequences that form G-quadruplexes can be viewed as potential “hot-spots” for DNA oxidation. We propose that oxidation may destabilise the G-quadruplex structure, leading to its unfolding into the duplex structure, affecting gene expression. This would imply a possible mechanism by which oxidation may impact on oncogene expression. This work investigates the effect of oxidation on two biologically relevant G-quadruplex structures through 500 ns molecular dynamics simulations on those found in the promoter regions of the c-Kit and c-Myc oncogenes. The results show oxidation having a detrimental effect on stability of the structure, substantially destabilising the c-Kit quadruplex, and with a more attenuated effect on the c-Myc quadruplex. Results are suggestive of a novel route for oxidation-mediated oncogenesis and may have wider implications for genome stability. PMID:22928025

  17. Differential expression of the ufo/axl oncogene in human leukemia-lymphoma cell lines.

    PubMed

    Challier, C; Uphoff, C C; Janssen, J W; Drexler, H G

    1996-05-01

    The ufo protein (also termed axl) is a member of a new family of receptor tyrosine kinases and is encoded by a transforming gene that was initially isolated from primary human myeloid leukemia cells by DNA-mediated transformation of NIH/3T3 cells. The ligand, Gas6, a protein S-related molecule lacking any known function yet, has recently been identified. We report the expression pattern of ufo mRNA in a panel of 76 human continuous leukemia-lymphoma cell lines. The gene was not expressed in cell lines derived from lymphoid malignancies (n=28), but transcription was seen in 3/11 myeloid, 0/6 monocytic, 9/13 erythroid and 11/18 megakaryocytic cell lines. Several cell lines were treated with phorbol ester leading to significant upregulation of the ufo message in constitutively positive cells. An apparent ufo mRNA overexpression was not found in any of the positive leukemia cell lines, but was identified in the drug-resistant subclones of the cervix carcinoma cell line HeLa. Southern blot analysis of restriction enzyme-digested genomic DNA did not provide evidence for gene amplification, but the HeLa subclones showed banding patterns suggestive of gene rearrangement. Two main ufo mRNA bands of 3.2 and 5.0 kb were identified; no differences in the half-lives (t1/2 = 2.5 h) of these two mRNA species could be identified. In summary, ufo, representing a novel type of receptor tyrosine kinase, is expressed solely in myeloid and erythro-megakaryocytic leukemias but not in lymphoid malignancies. These and previous data suggest an involvement of the ufo receptor tyrosine kinase in normal and malignant myelopoiesis; however, its exact role, if any, and mode of operation in leukemogenesis remains to be determined.

  18. Hepatocyte specific expression of an oncogenic variant of β-catenin results in cholestatic liver disease

    PubMed Central

    Lemberger, Ursula J.; Fuchs, Claudia D.; Karer, Matthias; Haas, Stefanie; Stojakovic, Tatjana; Schöfer, Christian; Marschall, Hanns-Ulrich; Wrba, Fritz; Taketo, Makoto M.; Egger, Gerda; Trauner, Michael; Österreiche, Christophr H.

    2016-01-01

    Background The Wnt/β-catenin signaling pathway plays a crucial role in embryonic development, tissue homeostasis, wound healing and malignant transformation in different organs including the liver. The consequences of continuous β-catenin signaling in hepatocytes remain elusive. Results Livers of Ctnnb1CA hep mice were characterized by disturbed liver architecture, proliferating cholangiocytes and biliary type of fibrosis. Serum ALT and bile acid levels were significantly increased in Ctnnb1CA hep mice. The primary bile acid synthesis enzyme Cyp7a1 was increased whereas Cyp27 and Cyp8b1 were reduced in Ctnnb1CA hep mice. Expression of compensatory bile acid transporters including Abcb1, Abcb4, Abcc2 and Abcc4 were significantly increased in Ctnnb1CA hep mice while Ntcp was reduced. Accompanying changes of bile acid transporters favoring excretion of bile acids were observed in intestine and kidneys of Ctnnb1CA hep mice. Additionally, disturbed bile acid regulation through the FXR-FGF15-FGFR4 pathway was observed in mice with activated β-catenin. Materials and Methods Mice with a loxP-flanked exon 3 of the Ctnnb1 gene were crossed to Albumin-Cre mice to obtain mice with hepatocyte-specific expression of a dominant stable form of β-catenin (Ctnnb1CA hep mice). Ctnnb1CA hep mice were analyzed by histology, serum biochemistry and mRNA profiling. Conclusions Expression of a dominant stable form of β-catenin in hepatocytes results in severe cholestasis and biliary type fibrosis. PMID:27895309

  19. Perylene and coronene derivatives binding to G-rich promoter oncogene sequences efficiently reduce their expression in cancer cells.

    PubMed

    Micheli, Emanuela; Altieri, Alessandro; Cianni, Lorenzo; Cingolani, Chiara; Iachettini, Sara; Bianco, Armandodoriano; Leonetti, Carlo; Cacchione, Stefano; Biroccio, Annamaria; Franceschin, Marco; Rizzo, Angela

    2016-06-01

    A novel approach to cancer therapeutics is emerging in the field of G-quadruplex (G4) ligands, small molecules designed to stabilize four-stranded structures that can form at telomeres as well as in other genomic sequences, including oncogene promoter sequences, 5'-UTR regions and introns. In this study, we investigated the binding activity of perylene and coronene derivatives PPL3C, CORON and EMICORON to G4 structures formed within the promoter regions of two important cancer-related genes, c-MYC and BCL-2, and their biochemical effects on gene and protein expression. In order to fully characterize the ability of the selected ligands to bind and stabilize the G4 structures originated by the c-MYC and BCL-2 promoter sequences, we performed electrospray ionization mass spectrometry (ESI-MS), Fluorescence Resonance Energy Transfer (FRET) measurements, Circular Dichroism (CD) spectra and polymerase stop assay. Altogether our results showed that the ligands had a high capacity in binding and stabilizing the G4 structures within the c-MYC and BCL-2 promoter sequences in vitro. Notably, when we evaluated by quantitative real-time PCR and western blotting analysis, the effects of treatment with the different G4 ligands on c-MYC and BCL2 expression in a human melanoma cell line, EMICORON appeared the most effective compound in reducing the mRNA and protein levels of both genes. These results encourage to consider EMICORON as a promising example of multimodal class of an antineoplastic drug, affecting different tumor crucial pathways simultaneously: telomere maintenance (as previously described), cell proliferation and apoptosis via down-regulation of both c-MYC and BCL-2 (this paper).

  20. Ha-ras oncogene expression directed by a milk protein gene promoter: tissue specificity, hormonal regulation, and tumor induction in transgenic mice

    SciTech Connect

    Andres, A.C.; Schoenenberger, C.A.; Groner, B.; Henninghausen, L.; LeMeur, M.; Gelinger, P.

    1987-03-01

    The activated human Ha-ras oncogene was subjected to the control of the promoter region of the murine whey acidic protein (Wap) gene, which is expressed in mammary epithelial cells in response to lactogenic hormones. The Wap-ras gene was stably introduced into the mouse germ line of five transgenic mice (one male and four females). Wap-ras expression was observed in the mammary glands of lactating females in two lines derived from female founders. The tissue-directed and hormone-dependent Wap expression was conferred on the Ha-ras oncogene. The signals governing Wap expression are located within 2.5 kilobases of 5' flanking sequence. The other two lines derived from female founders did not express the chimeric gene. In the line derived from the male founder the Wap-ras gene is integrated into the Y chromosome. Expression was found in the salivary gland of male animals only. After a long latency, Wap-ras-expressing mice developed tumors. The tumors arose in tissues expressing Wap-ras - i.e., mammary or salivary glands. Compared to the corresponding nonmalignant tissues, Wap-ras expression was enhanced in the tumors.

  1. An amphotropic retroviral vector expressing a mutant gsp oncogene: effects on human thyroid cells in vitro.

    PubMed

    Ivan, M; Ludgate, M; Gire, V; Bond, J A; Wynford-Thomas, D

    1997-08-01

    Point mutations of the gsp protooncogene (encoding the alpha-subunit of the Gs protein) that constitutively activate the cAMP signaling pathway are a common feature of and a plausible causative mechanism for thyroid hyperfunctioning adenomas (hot nodules). To investigate the extent to which mutant gsp acting alone can induce proliferation of thyroid follicular cells, we generated an amphotropic retroviral vector (based on the pBABE-neo plasmid and psi-CRIP packaging line) to permit stable introduction of a hemagglutinin-tagged Gln227-->Leu mutant gsp gene into normal human thyrocytes in vitro. The biological activity of the vector was confirmed by detection of HA-tagged Gsp protein expression and induction of cAMP synthesis in selected target cells. Normal human thyroid follicular cells in primary monolayer culture were infected with the gsp retroviral vector or with corresponding vectors expressing mutant H-ras or neo only as positive and negative controls, respectively. Although, as before, mutant ras generated 10-20 well differentiated epithelial colonies/dish of 10(5) infected cells, with an average lifespan of 15-20 population doublings, only small groups of no more than 15-50 differentiated thyrocytes were observed with the gsp vector. In addition to standard conditions (10% FCS), infections were performed in reduced serum (1% FCS, TSH, and insulin), in the presence of isobutylylmethylxanthine, or in the presence of agents capable of closing gap junctions, with no significant difference in outcome. Although little or no proliferative response was observed regardless of the conditions, there was clear evidence of morphological response (rearrangement of the actin cytoskeleton and increased cell size). The results suggest that gsp mutation may not be a sufficient proliferogenic stimulus by itself to account for hot nodule formation.

  2. Low Expression of miR-196b Enhances the Expression of BCR-ABL1 and HOXA9 Oncogenes in Chronic Myeloid Leukemogenesis

    PubMed Central

    Liu, Yue; Zheng, Wenling; Song, Yanbin; Ma, Wenli; Yin, Hong

    2013-01-01

    MicroRNAs (miRNAs) can function as tumor suppressors or oncogene promoters during tumor development. In this study, low levels of expression of miR-196b were detected in patients with chronic myeloid leukemia. Bisulfite genomic sequencing PCR and methylation-specific PCR were used to examine the methylation status of the CpG islands in the miR-196b promoter in K562 cells, patients with leukemia and healthy individuals. The CpG islands showed more methylation in patients with chronic myeloid leukemia compared with healthy individuals (P<0.05), which indicated that low expression of miR-196b may be associated with an increase in the methylation of CpG islands. The dual-luciferase reporter assay system demonstrated that BCR-ABL1 and HOXA9 are the target genes of miR-196b, which was consistent with predictions from bioinformatics software analyses. Further examination of cell function indicated that miR-196b acts to reduce BCR-ABL1 and HOXA9 protein levels, decrease cell proliferation rate and retard the cell cycle. A low level of expression of miR-196b can cause up-regulation of BCR-ABL1 and HOXA9 expression, which leads to the development of chronic myeloid leukemia. MiR-196b may represent an effective target for chronic myeloid leukemia therapy. PMID:23894305

  3. Effect of Neem Leaf Extract (Azadirachta indica) on c-Myc Oncogene Expression in 4T1 Breast Cancer Cells of BALB/c Mice

    PubMed Central

    Othman, Fauziah; Motalleb, Gholamreza; Lam Tsuey Peng, Sally; Rahmat, Asmah; Basri, Rusliza; Pei Pei, Chong

    2012-01-01

    Objective: Breast cancer is the most common cause of cancer-related deaths in women both worldwide and in Malaysia. Azadirachta indica (A. Juss), commonly known as neem, is one of the most versatile medicinal plants that has gained worldwide prominence due to its medicinal properties. However, the anticancer effect of ethanolic neem leaf extract against breast cancer has not been documented. The purpose of the present study is to investigate the effect of neem leaf extract on c-Myc oncogene expression in 4T1 breast cancer BALB/c mice. Materials and Methods: In this experimental study, A total of 48 female BALB/c mice were divided randomly into four groups of 12 mice per group: i.cancer control (CC) treated with 0.5% Tween 20 in PBS, ii. 0.5 µg/mL tamoxifen citrate (CT), iii. 250 mg/kg neem leaf extract (C250), and iv. 500 mg/kg neem leaf extract (C500). in situ reverse transcription polymerase chain reaction (in situ RT-PCR) was applied to evaluate suppression of c-Myc oncogene expression in breast cancer tissue. Results: The C500 group showed significant (p<0.05) suppression of c-Myc oncogene expression compared to the CC group. Conclusion: c-Myc was found to be down regulated under the effect of 500 mg/kg ethanolic neem leaf extract. PMID:23626938

  4. Deconstruction of Oncogenic K-RAS Signaling Reveals Focal Adhesion Kinase as a Novel Therapeutic Target in NSCLC

    DTIC Science & Technology

    2015-10-01

    SUPPLEMENTARY NOTES 14. ABSTRACT About 25% of lung adenocarcinomas express mutant KRAS (KM) often is association with co-occurring mutations that...There are no therapies that target cancers that express mutant KRAS. Thus, it is notable that inhibition of FAK causes cell death specifically in KM...lung cancer cells (KMLC) that are either CDKN2A mutant or p53 mutant . Furthermore, we found that pharmacologic inhibition of FAK causes the

  5. Expression of the EWS/FLI-1 oncogene in murine primary bone-derived cells Results in EWS/FLI-1-dependent, ewing sarcoma-like tumors.

    PubMed

    Castillero-Trejo, Yeny; Eliazer, Susan; Xiang, Lilin; Richardson, James A; Ilaria, Robert L

    2005-10-01

    Ewing sarcoma is the second most common malignant pediatric bone tumor. Over 80% of Ewing sarcoma contain the oncogene EWS/FLI-1, which encodes the EWS/FLI-1 oncoprotein, a hybrid transcription factor comprised of NH2-terminal sequences from the RNA-binding protein EWS and the DNA-binding and COOH-terminal regions of the Ets transcription factor FLI-1. Although numerous genes are dysregulated by EWS/FLI-1, advances in Ewing sarcoma cancer biology have been hindered by the lack of an animal model because of EWS/FLI-1-mediated cytotoxicity. In this study, we have developed conditions for the isolation and propagation of murine primary bone-derived cells (mPBDC) that stably express EWS/FLI-1. Early-passage EWS/FLI-1 mPBDCs were immortalized in culture but inefficient at tumor induction, whereas later-passage cells formed sarcomatous tumors in immunocompetent syngeneic mice. Murine EWS/FLI-1 tumors contained morphologically primitive cells that lacked definitive lineage markers. Molecular characterization of murine EWS/FLI-1 tumors revealed that some but not all had acquired a novel, clonal in-frame p53 mutation associated with a constitutive loss of p21 expression. Despite indications that secondary events facilitated EWS/FLI-1 mPBDC tumorigenesis, cells remained highly dependent on EWS/FLI-1 for efficient transformation in clonogenic assays. This Ewing sarcoma animal model will be a useful tool for dissecting the molecular pathogenesis of Ewing sarcoma and provides rationale for the broader use of organ-specific progenitor cell populations for the study of human sarcoma.

  6. Prevention of tumor growth driven by PIK3CA and HPV oncogenes by targeting mTOR signaling with metformin in oral squamous carcinomas expressing OCT3

    PubMed Central

    Madera, Dmitri; Vitale-Cross, Lynn; Martin, Daniel; Schneider, Abraham; Molinolo, Alfredo A.; Gangane, Nitin; Carey, Thomas E.; McHugh, Jonathan B.; Komarck, Christine M.; Walline, Heather M.; William, William N.; Seethala, Raja R.; Ferris, Robert; Gutkind, J. Silvio

    2015-01-01

    Most head and neck squamous cell carcinomas (HNSCC) exhibit a persistent activation of the PI3K-mTOR signaling pathway. We have recently shown that metformin, an oral antidiabetic drug that is also used to treat lipodystrophy in HIV-infected (HIV+) individuals, diminishes mTOR activity and prevents the progression of chemically-induced experimental HNSCC premalignant lesions. Here, we explored the preclinical activity of metformin in HNSCCs harboring PIK3CA mutations and HPV oncogenes, both representing frequent HNSCC alterations, aimed at developing effective targeted preventive strategies. The biochemical and biological effects of metformin were evaluated in representative HNSCC cells expressing mutated PIK3CA or HPV oncogenes (HPV+). The oral delivery of metformin was optimized to achieve clinical relevant blood levels. Molecular determinants of metformin sensitivity were also investigated, and their expression levels examined in a large collection of HNSCC cases. We found that metformin inhibits mTOR signaling and tumor growth in HNSCC cells expressing mutated PIK3CA and HPV oncogenes, and that these activities require the expression of organic cation transporter 3 (OCT3/SLC22A3), a metformin uptake transporter. Co-expression of OCT3 and the mTOR pathway activation marker pS6 were observed in most HNSCC cases, including those arising in HIV+ patients. Activation of the PI3K-mTOR pathway is a widespread event in HNSCC, including HPV− and HPV+ lesions arising in HIV+ patients, all of which co-express OCT3. These observations may provide a rationale for the clinical evaluation of metformin to halt HNSCC development from precancerous lesions, including in HIV+ individuals at risk of developing HPV-associated cancers. PMID:25681087

  7. Her2/neu Protein Expression and Oncogene Amplification in Gastric Carcinoma with Clinico-Pathological Correlation in Egyptian Patients

    PubMed Central

    Hadi, Ahmed Abdel; Hindawi, Ali El; Hareedy, Amal; Khalil, Heba; Ashiry, Ranya Al; Elia, Shady; Sadek, Ahmed; Magdy, Mona; Atta, Rafatt; Anas, Amgad; Bakr, Hisham; Hammam, Olfat

    2016-01-01

    AIM: Amplification of the Her2/neu gene and overexpression of the Her2/neu protein in gastric carcinoma (GC) is a golden criterion for target therapy with trastuzumab (Herceptin). We aim to evaluate the immunohistochemical protein expression and amplification of the oncogene Her2/neu by FISH technique in the epithelial gastric carcinoma and to compare their association with different clinicopathologic parameters aiming at identifying positive cases that may benefit from targeted therapy. MATERIALS AND METHODS: This study was done on eighty-five tumour tissue samples from patients with GC as well as thirty non-malignant lesions (Gastritis, intestinal metaplasia, adenoma with low-grade dysplasia, adenoma with high-grade dysplasia). All were immunohistochemically stained with Her2/neu antibody. RESULTS: All equivocal and some selected GC cases were submitted for FISH technique to detect Her2/neu gene amplification. By immunohistochemistry twenty-three cases (27%) were defined as positive for Her2/neu gene amplification and/or protein overexpression. The levels of Her2/neu positive (3+), Her2/neu equivocal (2+) and Her2/neu negative (1+/0) were measurable in 14.2%, 32.9% and 52.9% of the samples, respectively. FISH showed that Her2/neu gene was amplified in 22 cases, 10 Her2/neu positive (3+), 11 (39.3%) Her2/neu equivocal (2+) and 1 Her2/neu negative (1+) cases with IHC staining those who can benefit from anti Her2/neu target therapy. Her2/neu was overexpressed positivity (3+) more in intestinal type and mixed carcinoma, and moderately differentiated tumours. None of gastritis, intestinal metaplasia or adenoma with low-grade dysplasia cases showed positivity for Her2/neu (3+). The Her2/neu positivity (3+) was associated with both adenocarcinoma cases and high-grade dysplasia (P = 0.002). CONCLUSIONS: The results highlight the necessity of FISH test for further categorization when gastric cancer cases are equivocal (2+) by IHC to determine eligibility for the targeted

  8. Concordant down-regulation of proto-oncogene PML and major histocompatibility antigen HLA class I expression in high-grade prostate cancer.

    PubMed

    Zhang, Huiming; Melamed, Jonathan; Wei, Ping; Cox, Karen; Frankel, Wendy; Bahnson, Robert R; Robinson, Nikki; Pyka, Ron; Liu, Yang; Zheng, Pan

    2003-02-14

    Recognition of tumor cells by cytolytic T lymphocytes depends on cell surface MHC class I expression. As a mechanism to evade T cell recognition, many malignant cancer cells, including those of prostate cancer, down-regulate MHC class I. For the majority of human cancers, the molecular mechanism of MHC class I down regulation is unclear, although it is well established that MHC class I down-regulation is often associated with the down-regulation of multiple genes devoted to antigen presentation. Since the promyelocytic leukemia (PML) proto-oncogene controls multiple antigen-presentation genes in some murine cancer cells, we analyzed the expression of proto-oncogene PML and MHC class I in high-grade prostate cancer. We found that 30 of 37 (81%) prostate adenocarcinoma cases with a Gleason grade of 7-8 had more than 50% down-regulation of HLA class I expression. Among these, 22 cases (73.3%) had no detectable PML protein, while 4 cases (13.3%) showed partial PML down-regulation. In contrast, all 7 cases of prostate cancer with high expression of cell surface HLA class I had high levels of PML expression. Concordant down-regulation of HLA and PML was observed in different histological patterns of prostate adenocarcinoma. These results suggest that in high-grade prostate cancer, malfunction of proto-oncogene PML is a major factor in the down-regulation of cell surface HLA class I molecules, the target molecules essential for the direct recognition of cancer cells by cytolytic T lymphocytes.

  9. Inhibition of Oncogenic BRAF Activity by Indole-3-Carbinol Disrupts Microphthalmia-Associated Transcription Factor Expression and Arrests Melanoma Cell Proliferation

    PubMed Central

    Kundu, Aishwarya; Quirit, Jeanne G.; Khouri, Michelle G.; Firestone, Gary L.

    2016-01-01

    Indole-3-carbinol (I3C), an anti-cancer phytochemical derived from cruciferous vegetables, strongly inhibited proliferation and down-regulated protein levels of the melanocyte master regulator micropthalmia-associated transcription factor (MITF-M) in oncogenic BRAF-V600E expressing melanoma cells in culture as well as in vivo in tumor xenografted athymic nude mice. In contrast, wild type BRAF-expressing melanoma cells remained relatively insensitive to I3C anti-proliferative signaling. In BRAF-V600E-expressing melanoma cells, I3C treatment inhibited phosphorylation of MEK and ERK/MAPK, the down stream effectors of BRAF. The I3C anti-proliferative arrest was concomitant with the down-regulation of MITF-M transcripts and promoter activity, loss of endogenous BRN-2 binding to the MITF-M promoter, and was strongly attenuated by expression of exogenous MITF-M. Importantly, in vitro kinase assays using immunoprecipitated BRAF-V600E and wild type BRAF demonstrated that I3C selectively inhibited the enzymatic activity of the oncogenic BRAF-V600E but not of the wild type protein. In silico modeling predicted an I3C interaction site in the BRAF-V600E protomer distinct from where the clinically used BRAF-V600E inhibitor Vemurafenib binds to BRAF-V600E. Consistent with this prediction, combinations of I3C and Vemurafenib more potently inhibited melanoma cell proliferation and reduced MITF-M levels in BRAF-V600E expressing melanoma cells compared to the effects of each compound alone. Thus, our results demonstrate that oncogenic BRAF-V600E is a new cellular target of I3C that implicate this indolecarbinol compound as a potential candidate for novel single or combination therapies for melanoma. PMID:26878440

  10. Loss of RALT/MIG-6 expression in ERBB2-amplified breast carcinomas enhances ErbB-2 oncogenic potency and favors resistance to Herceptin.

    PubMed

    Anastasi, Sergio; Sala, Gianluca; Huiping, Chen; Caprini, Elisabetta; Russo, Giandomenico; Iacovelli, Stefano; Lucini, Fabiana; Ingvarsson, Sigurdur; Segatto, Oreste

    2005-06-30

    An emerging paradigm holds that loss of negative signalling to receptor tyrosine kinases (RTKs) is permissive for their oncogenic activity. Herein, we have addressed tumor suppression by RALT/MIG-6, a transcriptionally controlled feedback inhibitor of ErbB RTKs, in breast cancer cells. Knockdown of RALT expression by RNAi enhanced the EGF-dependent proliferation of normal breast epithelial cells, indicating that loss of RALT signalling in breast epithelium may represent an advantageous condition during ErbB-driven tumorigenesis. Although mutational inactivation of the RALT gene was not detected in human breast carcinomas, RALT mRNA and protein expression was strongly and selectively reduced in ERBB2-amplified breast cancer cell lines. Reconstitution of RALT expression in ERBB2-amplified SKBr-3 and BT474 cells inhibited ErbB-2-dependent mitogenic signalling and counteracted the ability of ErbB ligands to promote resistance to the ErbB-2-targeting drug Herceptin. Thus, loss of RALT expression cooperates with ERBB2 gene amplification to drive full oncogenic signalling by the ErbB-2 receptor. Moreover, loss of RALT signalling may adversely affect tumor responses to ErbB-2-targeting agents.

  11. Hematopoietic expression of oncogenic BRAF promotes aberrant growth of monocyte-lineage cells resistant to PLX4720

    PubMed Central

    Kamata, Tamihiro; Dankort, David; Kang, Jing; Giblett, Susan; Pritchard, Catrin A.; McMahon, Martin; Leavitt, Andrew D.

    2013-01-01

    Mutational activation of BRAF leading to expression of the BRAFV600E oncoprotein was recently identified in a high percentage of specific hematopoietic neoplasms in monocyte/histiocyte and mature B-cell lineages. Although BRAFV600E is a driver oncoprotein and pharmacological target in solid tumors such as melanoma, lung and thyroid cancer, it remains unknown whether BRAFV600E is an appropriate therapeutic target in hematopoietic neoplasms. To address this critical question, we generated a mouse model expressing inducible BRAFV600E in the hematopoietic system, and evaluated the efficacy of pathway-targeted therapeutics against primary hematopoietic cells. In this model, BRAFV600E expression conferred cytokine-independent growth to monocyte/macrophage-lineage progenitors leading to aberrant in vivo and in vitro monocyte/macrophage expansion. Furthermore, transplantation of BRAFV600E-expressing bone marrow cells promoted an in vivo pathology most notable for monocytosis in hematopoietic tissues and visceral organs. In vitro analysis revealed that MEK inhibition, but not RAF inhibition, effectively suppressed cytokine-independent clonal growth of monocyte/macrophage-lineage progenitors. However, combined RAF and PI3K inhibition effectively inhibited cytokine-independent colony formation, suggesting autocrine PI3K pathway activation. Taken together, these results provide evidence that constitutively activated BRAFV600E drives aberrant proliferation of monocyte-lineage cells. This study supports the development of pathway-targeted therapeutics in the treatment of BRAFV600E-expressing hematopoietic neoplasms in the monocyte/histiocyte lineage. PMID:24152792

  12. 5-aza-2'-deoxycytidine (DAC) treatment downregulates the HPV E6 and E7 oncogene expression and blocks neoplastic growth of HPV-associated cancer cells.

    PubMed

    Stich, Maximilian; Ganss, Lennard; Puschhof, Jens; Prigge, Elena-Sophie; Reuschenbach, Miriam; Guiterrez, Ana; Vinokurova, Svetlana; von Knebel Doeberitz, Magnus

    2016-07-16

    High-risk human papillomaviruses (hr HPVs) may cause various human cancers and associated premalignant lesions. Transformation of the host cells is triggered by overexpression of the viral oncogenes E6 and E7 that deregulate the cell cycle and induce chromosomal instability. This process is accompanied by hypermethylation of distinct CpG sites resulting in silencing of tumor suppressor genes, inhibition of the viral E2 mediated control of E6 and E7 transcription as well as deregulated expression of host cell microRNAs. Therefore, we hypothesized that treatment with demethylating agents might restore those regulatory mechanisms. Here we show that treatment with 5-aza-2'-deoxycytidine (DAC) strongly decreases the expression of E6 and E7 in a panel of HPV-transformed cervical cancer and head and neck squamous cell carcinoma cell lines. Reduction of E6 and E7 further resulted in increased target protein levels including p53 and p21 reducing the proliferation rates and colony formation abilities of the treated cell lines. Moreover, DAC treatment led to enhanced expression of tumor the suppressive miRNA-375 that targets and degrades E6 and E7 transcripts. Therefore, we suggest that DAC treatment of HPV-associated cancers and respective precursor lesions may constitute a targeted approach to subvert HPV oncogene functions that deserves testing in clinical trials.

  13. Protein kinase C-independent expression of stromelysin by platelet-derived growth factor, ras oncogene, and phosphatidylcholine-hydrolyzing phospholipase C.

    PubMed

    Diaz-Meco, M T; Quiñones, S; Municio, M M; Sanz, L; Bernal, D; Cabrero, E; Saus, J; Moscat, J

    1991-11-25

    Changes in the expression of several genes play critical roles in cell growth and tumor transformation. A number of proteases are increased in some tumors, and the level of these enzymes correlates with the metastatic potential of several cancer cell lines. Stromelysin, with the widest substrate specificity, can degrade the extracellular matrix conferring metastatic potential to tumor cells. The mechanisms whereby growth factors and oncogenes control the expression of stromelysin are beginning to be characterized. In the study shown here we also identify a region in the stromelysin promoter which is involved in the induction of stromelysin in response to platelet-derived growth factor, phosphatidylcholine-hydrolyzing phospholipase C, and ras oncogene. Our results are consistent with the notion that platelet-derived growth factor/phosphatidylcholine-hydrolyzing phospholipase C induces stromelysin gene expression through a phorbol myristate acetate/protein kinase C-independent mechanism by acting through elements in the stromelysin promoter distinct from the 12-O-tetradecanoylphorbol-13-acetate-responsive element.

  14. Downregulation of oncogenic RAS and c-Myc expression in MOLT-4 leukaemia cells by a salicylaldehyde semicarbazone copper(II) complex.

    PubMed

    Goh, Yan-Yih; Yan, Yaw-Kai; Tan, Nguan Soon; Goh, Su-Ann; Li, Shang; Teoh, You-Chuan; Lee, Peter P F

    2016-11-14

    Copper complexes with potent anti-tumor effect have been extensively developed. Most investigations of their modes of action focused on the biomolecular targets but not the signal transduction between target binding and cell death. We have previously shown that the cytotoxic complex pyridine(2,4-dihydroxybenzaldehyde dibenzyl semicarbazone)copper(II) (complex 1) shows selective binding to human telomeric G-quadruplex DNA over double-stranded DNA in vitro. Herein, we elucidate the mechanism of action by which complex 1 induces apoptosis in MOLT-4 cells. Complex 1 accumulates in the nuclei and differentially downregulates the expression of c-Myc, c-Kit and KRAS oncogenes. Chemical affinity capture assay results show that the complex is associated with c-Myc and KRAS quadruplex sequences in MOLT-4 cells. We further showed that the reduction in Ras protein expression resulted in attenuated MEK-ERK and PI3K-Akt signalling activities, leading to the activation of caspase-dependent apoptosis. Notably, complex 1 increased the sensitivity of MOLT-4 cells to cisplatin and vice versa. Overall, we demonstrated that complex 1 induces apoptosis, at least in part, by suppressing KRAS, c-Kit and c-Myc oncogene expression and the pro-survival MEK-ERK and PI3K-Akt signalling pathways.

  15. Downregulation of oncogenic RAS and c-Myc expression in MOLT-4 leukaemia cells by a salicylaldehyde semicarbazone copper(II) complex

    PubMed Central

    Goh, Yan-Yih; Yan, Yaw-Kai; Tan, Nguan Soon; Goh, Su-Ann; Li, Shang; Teoh, You-Chuan; Lee, Peter P. F.

    2016-01-01

    Copper complexes with potent anti-tumor effect have been extensively developed. Most investigations of their modes of action focused on the biomolecular targets but not the signal transduction between target binding and cell death. We have previously shown that the cytotoxic complex pyridine(2,4-dihydroxybenzaldehyde dibenzyl semicarbazone)copper(II) (complex 1) shows selective binding to human telomeric G-quadruplex DNA over double-stranded DNA in vitro. Herein, we elucidate the mechanism of action by which complex 1 induces apoptosis in MOLT-4 cells. Complex 1 accumulates in the nuclei and differentially downregulates the expression of c-Myc, c-Kit and KRAS oncogenes. Chemical affinity capture assay results show that the complex is associated with c-Myc and KRAS quadruplex sequences in MOLT-4 cells. We further showed that the reduction in Ras protein expression resulted in attenuated MEK-ERK and PI3K-Akt signalling activities, leading to the activation of caspase-dependent apoptosis. Notably, complex 1 increased the sensitivity of MOLT-4 cells to cisplatin and vice versa. Overall, we demonstrated that complex 1 induces apoptosis, at least in part, by suppressing KRAS, c-Kit and c-Myc oncogene expression and the pro-survival MEK-ERK and PI3K-Akt signalling pathways. PMID:27841290

  16. Genetic and epigenetic silencing of mircoRNA-506-3p enhances COTL1 oncogene expression to foster non-small lung cancer progression.

    PubMed

    Guo, Shanqi; Yang, Peiying; Jiang, Xingkang; Li, Xiaojiang; Wang, Yuanyuan; Zhang, Xin; Sun, Binxu; Zhang, Yao; Jia, Yingjie

    2017-01-03

    Although previous studies suggested that microRNA-506-3p (miR-506-3p) was frequently downregulated, and functioned as a tumor suppressor in several cancers, the biological role and intrinsic regulatory mechanisms of miR-506-3p in non-small cell lung cancer (NSCLC) remain elusive. The present study found miR-506-3p expression was downregulated in advanced NSCLC tissues and cell lines. The expression of miR-506-3p in NSCLC was inversely correlated with larger tumor size, advanced TNM stage and lymph node metastasis. In addition, we also found patients with lower expression of miR-506-3p had a poor prognosis than those patients with higher expression of miR-506-3p. Function studies demonstrated that aberrant miR-506-3p expression modulates tumor cell growth, cell mobility, cell migration and invasion in vitro and in vivo. Mechanistic investigations manifested that coactosin-like protein 1 (COTL1) was a direct downstream target of miR-506-3p. Knockdown of COTL1 mimicked the tumor-suppressive effects of miR-506-3p overexpression in A549 cells, whereas COTL1 overexpression enhanced the tumorigenic function in HCC827 cells. Importantly, we also found GATA3 transcriptionally actives miR-506-3p expression, and the long non-coding RNA urothelial carcinoma-associated 1 (UCA1) exerts oncogenic function in NSCLC by competitively 'sponging' miRNA-506. Together, our combined results elucidated genetic and epigenetic silencing of miR-506-3p enhances COTL1 oncogene expression to foster NSCLC progression.

  17. Genetic and epigenetic silencing of mircoRNA-506-3p enhances COTL1 oncogene expression to foster non-small lung cancer progression

    PubMed Central

    Li, Xiaojiang; Wang, Yuanyuan; Zhang, Xin; Sun, Binxu; Zhang, Yao; Jia, Yingjie

    2017-01-01

    Although previous studies suggested that microRNA-506-3p (miR-506-3p) was frequently downregulated, and functioned as a tumor suppressor in several cancers, the biological role and intrinsic regulatory mechanisms of miR-506-3p in non-small cell lung cancer (NSCLC) remain elusive. The present study found miR-506-3p expression was downregulated in advanced NSCLC tissues and cell lines. The expression of miR-506-3p in NSCLC was inversely correlated with larger tumor size, advanced TNM stage and lymph node metastasis. In addition, we also found patients with lower expression of miR-506-3p had a poor prognosis than those patients with higher expression of miR-506-3p. Function studies demonstrated that aberrant miR-506-3p expression modulates tumor cell growth, cell mobility, cell migration and invasion in vitro and in vivo. Mechanistic investigations manifested that coactosin-like protein 1 (COTL1) was a direct downstream target of miR-506-3p. Knockdown of COTL1 mimicked the tumor-suppressive effects of miR-506-3p overexpression in A549 cells, whereas COTL1 overexpression enhanced the tumorigenic function in HCC827 cells. Importantly, we also found GATA3 transcriptionally actives miR-506-3p expression, and the long non-coding RNA urothelial carcinoma-associated 1 (UCA1) exerts oncogenic function in NSCLC by competitively ‘sponging’ miRNA-506. Together, our combined results elucidated genetic and epigenetic silencing of miR-506-3p enhances COTL1 oncogene expression to foster NSCLC progression. PMID:27893417

  18. Oncogenic activation of the PI3K/Akt pathway promotes cellular glucose uptake by downregulating the expression of thioredoxin-interacting protein.

    PubMed

    Hong, Shin Yee; Yu, Fa-Xing; Luo, Yan; Hagen, Thilo

    2016-05-01

    Oncogenic activation of the PI3K/Akt pathway is known to play an important role to promote glucose metabolism in cancer cells. However, the molecular mechanism through which the PI3K/Akt signalling pathway promotes glucose utilisation in cancer cells is still not well understood. It has recently been shown that the oncogenic activation of the PI3K/Akt/mTOR signalling in lung adenocarcinoma is important in promoting the localisation of glucose transporter 1 (GLUT1) at the plasma membrane. We thus hypothesised that the effect of constitutive activation of the PI3K/AKT signalling on glucose metabolism is mediated by thioredoxin interacting protein (TXNIP), a known regulator of the GLUT1 plasma membrane localisation. Consistent with previous studies, inhibition of the PI3K/Akt pathway decreased cellular glucose uptake. Furthermore, inhibition of PI3K/Akt signalling in non-small cell lung cancer (NSCLC) cell lines using clinically used tyrosine kinase inhibitors (TKIs) resulted in a decrease in GLUT1 membrane localisation. We also observed that inhibition of the PI3K/Akt pathway in various cell lines, including NSCLC cells, resulted in an increase in TXNIP expression. Importantly, knockdown of TXNIP using siRNA in the NSCLC cells promoted GLUT1 to be localised at the plasma membrane and reversed the effect of PI3K/Akt inhibitors. Together, our results suggest that the oncogenic activation of PI3K/Akt signalling promotes cellular glucose uptake, at least in part, through the regulation of TXNIP expression. This mechanism may contribute to the Warburg effect in cancer cells.

  19. Targeted disruption of the murine fps/fes proto-oncogene reveals that Fps/Fes kinase activity is dispensable for hematopoiesis.

    PubMed

    Senis, Y; Zirngibl, R; McVeigh, J; Haman, A; Hoang, T; Greer, P A

    1999-11-01

    The fps/fes proto-oncogene encodes a cytoplasmic protein-tyrosine kinase that is functionally implicated in the survival and terminal differentiation of myeloid progenitors and in signaling from several members of the cytokine receptor superfamily. To gain further insight into the physiological function of fps/fes, we targeted the mouse locus with a kinase-inactivating missense mutation. Mutant Fps/Fes protein was expressed at normal levels in these mice, but it lacked detectable kinase activity. Homozygous mutant animals were viable and fertile, and they showed no obvious defects. Flow cytometry analysis of bone marrow showed no statistically significant differences in the levels of myeloid, erythroid, or B-cell precursors. Subtle abnormalities observed in mutant mice included slightly elevated total leukocyte counts and splenomegaly. In bone marrow hematopoietic progenitor cell colony-forming assays, mutant mice gave slightly elevated numbers and variable sizes of CFU-granulocyte macrophage in response to interleukin-3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF). Tyrosine phosphorylation of Stat3 and Stat5A in bone marrow-derived macrophages was dramatically reduced in response to GM-CSF but not to IL-3 or IL-6. This suggests a distinct nonredundant role for Fps/Fes in signaling from the GM-CSF receptor that does not extend to the closely related IL-3 receptor. Lipopolysaccharide-induced Erk1/2 activation was also reduced in mutant macrophages. These subtle molecular phenotypes suggest a possible nonredundant role for Fps/Fes in myelopoiesis and immune responses.

  20. Structure of the Catalytic Domain of EZH2 Reveals Conformational Plasticity in Cofactor and Substrate Binding Sites and Explains Oncogenic Mutations

    PubMed Central

    Wu, Hong; Zeng, Hong; Dong, Aiping; Li, Fengling; He, Hao; Senisterra, Guillermo; Seitova, Alma; Duan, Shili; Brown, Peter J.; Vedadi, Masoud; Arrowsmith, Cheryl H.; Schapira, Matthieu

    2013-01-01

    Polycomb repressive complex 2 (PRC2) is an important regulator of cellular differentiation and cell type identity. Overexpression or activating mutations of EZH2, the catalytic component of the PRC2 complex, are linked to hyper-trimethylation of lysine 27 of histone H3 (H3K27me3) in many cancers. Potent EZH2 inhibitors that reduce levels of H3K27me3 kill mutant lymphoma cells and are efficacious in a mouse xenograft model of malignant rhabdoid tumors. Unlike most SET domain methyltransferases, EZH2 requires PRC2 components, SUZ12 and EED, for activity, but the mechanism by which catalysis is promoted in the PRC2 complex is unknown. We solved the 2.0 Å crystal structure of the EZH2 methyltransferase domain revealing that most of the canonical structural features of SET domain methyltransferase structures are conserved. The site of methyl transfer is in a catalytically competent state, and the structure clarifies the structural mechanism underlying oncogenic hyper-trimethylation of H3K27 in tumors harboring mutations at Y641 or A677. On the other hand, the I-SET and post-SET domains occupy atypical positions relative to the core SET domain resulting in incomplete formation of the cofactor binding site and occlusion of the substrate binding groove. A novel CXC domain N-terminal to the SET domain may contribute to the apparent inactive conformation. We propose that protein interactions within the PRC2 complex modulate the trajectory of the post-SET and I-SET domains of EZH2 in favor of a catalytically competent conformation. PMID:24367611

  1. Transformation of Rat-1 fibroblasts with the v-src oncogene induces inositol 1,4,5-trisphosphate 3-kinase expression.

    PubMed Central

    Woodring, P J; Garrison, J C

    1996-01-01

    Transformation of Rat-1 fibroblasts with the v-src oncogene leads to a 6- to 8-fold enhancement of the activity of the Ins(1,4,5)P3 3-kinase in cytosolic extracts [Johnson, Wasilenko, Mattingly, Weber and Garrison (1989) Science 246, 121-124]. This study confirms these results using another v-src-transformed Rat-1 cell line (B31 cells) and investigates the molecular mechanism by which pp60v-src activates Ins(1,4,5)P3 3-kinase. The mRNA and protein levels for two rat isoforms of Ins(1,4,5)P3 3-kinase were determined in the v-src-transformed cell line. Both the mRNA and protein levels for isoform A were elevated in v-src-transformed Rat-1 cells while those for isoform B were not significantly affected. Moreover, stable expression of either form of Ins(1,4,5)P3 3-kinase in the B31 v-src-transformed Rat-1 cell line did not result in tyrosine phosphorylation of Ins(1,4,5)P3 3-kinase A or B. These results suggest that at least one mechanism by which the v-src oncogene increases the activity of the Ins(1,4,5)P3 3-kinase in the Rat-1 transformed fibroblast is by increasing the level of expression of Ins(1,4,5)P3 3-kinase A. PMID:8870651

  2. Histone H3 lysine 23 acetylation is associated with oncogene TRIM24 expression and a poor prognosis in breast cancer.

    PubMed

    Ma, Li; Yuan, Lili; An, Jing; Barton, Michelle C; Zhang, Qingyuan; Liu, Zhaoliang

    2016-11-01

    Acetylated H3 lysine 23 (H3K23ac) is a specific histone post-translational modification recognized by oncoprotein TRIM24. However, it is not clear whether H3K23ac levels are correlated with TRIM24 expression and what role H3K23ac may have in cancer. In this study, we collected breast carcinoma samples from 121 patients and conducted immunohistochemistry to determine the levels of TRIM24 and H3K23ac in breast cancer. Our results demonstrated that TRIM24 expression is positively correlated with H3K23ac levels, and high levels of both TRIM24 and H3K23ac predict shorter overall survival of breast cancer patients. We also showed that both TRIM24 and H3K23ac are higher in HER2-positive patients, and their levels were positively correlated with HER2 levels in breast cancer. Moreover, TRIM24 expression is associated with estrogen receptor (ER) and progesterone receptor (PR) statuses in both our cohort and The Cancer Genome Atlas (TCGA) breast carcinoma. In summary, our results revealed an important role of TRIM24 and H3K23ac in breast cancer and provided further evidence that TRIM24 small-molecule inhibitors may benefit ER- and PR-negative or HER2-positive breast cancer patients.

  3. Identification of novel non-coding RNA-based negative feedback regulating the expression of the oncogenic transcription factor GLI1.

    PubMed

    Villegas, Victoria E; Rahman, Mohammed Ferdous-Ur; Fernandez-Barrena, Maite G; Diao, Yumei; Liapi, Eleni; Sonkoly, Enikö; Ståhle, Mona; Pivarcsi, Andor; Annaratone, Laura; Sapino, Anna; Ramírez Clavijo, Sandra; Bürglin, Thomas R; Shimokawa, Takashi; Ramachandran, Saraswathi; Kapranov, Philipp; Fernandez-Zapico, Martin E; Zaphiropoulos, Peter G

    2014-07-01

    Non-coding RNAs are a complex class of nucleic acids, with growing evidence supporting regulatory roles in gene expression. Here we identify a non-coding RNA located head-to-head with the gene encoding the Glioma-associated oncogene 1 (GLI1), a transcriptional effector of multiple cancer-associated signaling pathways. The expression of this three-exon GLI1 antisense (GLI1AS) RNA in cancer cells was concordant with GLI1 levels. siRNAs knockdown of GLI1AS up-regulated GLI1 and increased cellular proliferation and tumor growth in a xenograft model system. Conversely, GLI1AS overexpression decreased the levels of GLI1, its target genes PTCH1 and PTCH2, and cellular proliferation. Additionally, we demonstrate that GLI1 knockdown reduced GLI1AS, while GLI1 overexpression increased GLI1AS, supporting the role of GLI1AS as a target gene of the GLI1 transcription factor. Activation of TGFβ and Hedgehog signaling, two known regulators of GLI1 expression, conferred a concordant up-regulation of GLI1 and GLI1AS in cancer cells. Finally, analysis of the mechanism underlying the interplay between GLI1 and GLI1AS indicates that the non-coding RNA elicits a local alteration of chromatin structure by increasing the silencing mark H3K27me3 and decreasing the recruitment of RNA polymerase II to this locus. Taken together, the data demonstrate the existence of a novel non-coding RNA-based negative feedback loop controlling GLI1 levels, thus expanding the repertoire of mechanisms regulating the expression of this oncogenic transcription factor.

  4. Activation of human papillomavirus type 18 E6-E7 oncogene expression by transcription factor Sp1.

    PubMed Central

    Hoppe-Seyler, F; Butz, K

    1992-01-01

    The human papillomavirus 18 (HPV18) E6 and E7 proteins are considered to be primarily responsive for the transforming activity of the virus. In order to analyse the molecular mechanisms resulting in viral oncoprotein expression, it is necessary to identify the factors involved in the transcriptional regulation of the E6/E7 genes. Here we define by gel retardation experiments a sequence aberrant Sp1 binding site present in the promoter proximal part of the viral transcriptional control region (Upstream Regulatory Region, URR). Functional analyses employing transient reporter assays reveal that this Sp1 element is required for an efficient stimulation of the HPV18 E6/E7-promoter. Mutation of the Sp1 element in the natural context of the HPV18 URR leads to a strong decrease in the activity of the E6/E7-promoter in several cell lines. The magnitude of reduction varies between different cell types and is higher in cell lines of epithelial origin when compared with nonepithelial cells. Cotransfection assays using Sp1 expression vector systems further define the promoter proximal HPV18 Sp1 binding motif as a functional Sp1 element in vivo and show that its integrity is essential for the stimulation of the E6/E7-promoter by augmented levels of Sp1. These results indicate, that the cellular transcription factor Sp1 plays an important role for the stimulation of the E6/E7-promoter by the viral URR and represents a major determinant for the expression of HPV18 transforming genes E6 and E7. Images PMID:1336181

  5. Bivalent promoter marks and a latent enhancer may prime the leukaemia oncogene LMO1 for ectopic expression in T-cell leukaemia.

    PubMed

    Oram, S H; Thoms, J; Sive, J I; Calero-Nieto, F J; Kinston, S J; Schütte, J; Knezevic, K; Lock, R B; Pimanda, J E; Göttgens, B

    2013-06-01

    LMO1 is a transcriptional regulator and a T-acute lymphoblastic leukaemia (T-ALL) oncogene. Although first identified in association with a chromosomal translocation in T-ALL, the ectopic expression of LMO1 occurs far more frequently in the absence of any known mutation involving its locus. Given that LMO1 is barely expressed in any haematopoietic lineage, and activation of transcriptional drivers in leukaemic cells is not well described, we investigated the regulation of this gene in normal haematopoietic and leukaemic cells. We show that LMO1 has two promoters that drive reporter gene expression in transgenic mice to neural tissues known to express endogenous LMO1. The LMO1 promoters display bivalent histone marks in multiple blood lineages including T-cells, and a 3' flanking region at LMO1 +57 contains a transcriptional enhancer that is active in developing blood cells in transgenic mouse embryos. The LMO1 promoters become activated in T-ALL together with the 3' enhancer, which is bound in primary T-ALL cells by SCL/TAL1 and GATA3. Taken together, our results show that LMO1 is poised for expression in normal progenitors, where activation of SCL/TAL1 together with a breakdown of epigenetic repression of LMO1 regulatory elements induces ectopic LMO1 expression that contributes to the development and maintenance of T-ALL.

  6. The Oncogenic Response to MiR-335 Is Associated with Cell Surface Expression of Membrane-Type 1 Matrix Metalloproteinase (MT1-MMP) Activity.

    PubMed

    Rojas, Fausto; Hernandez, Maria E; Silva, Milagros; Li, Lihua; Subramanian, Subbaya; Wilson, Michael J; Liu, Ping

    2015-01-01

    MicroRNA miR-335 has been reported to have both tumor suppressor and oncogenic activities. In order to determine possible tissue and cell type differences in response to miR-335, we examined the effect of miR-335 on cell expression of MT1-MMP, a proteinase commonly expressed in tumors and associated with cell proliferation and migration. miR-335 increased cell surface expression of MT1-MMP in fibrosarcoma HT-1080 and benign prostate BPH-1 cells, but not in prostate LNCaP or breast MCF-7 tumor cells. miR-335 stimulated proliferation and cell migration in a wound healing in vitro assay in HT-1080, BPH-1, and U87 glioblastoma cells, cells which demonstrated significant cell surface expression of MT1-MMP. In contrast, miR-335 did not affect proliferation or migration in cells without a prominent plasma membrane associated MT1-MMP activity. Our data suggest that differences in response to miR-335 by tumor cells may lie in part in the mechanism of regulation of MT1-MMP production.

  7. In vivo evolution of c-rel oncogenic potential.

    PubMed

    Hrdlicková, R; Nehyba, J; Humphries, E H

    1994-04-01

    The c-rel proto-oncogene belongs to the NF-kappa B/rel and I kappa B gene families, which regulate several inducible processes, including self-defense/repair and embryogenesis. Transduction of the c-rel transcription factor by the avian retrovirus resulted in the formation of a highly oncogenic virus, reticuloendotheliosis virus strain T (REV-T), that encodes the oncogene v-rel. To examine the oncogenic potential of c-rel, we inserted it into a REV-T-based retroviral vector, rescued virus [REV-C(CSV)], and infected 1-day-old chicks. All birds developed tumors, and all cell lines established from REV-C-induced tumors expressed c-rel proteins that lacked C-terminal sequences. These proteins, responsible for both in vivo and in vitro cell proliferation, were apparently selected for their oncogenic potential. In order to examine the cooperation of C-terminal deletions with other oncogenic alterations in vivo, point mutations present in the N-terminal and middle regions of v-rel were analyzed by a similar protocol. The data obtained support four conclusions. (i) c-rel proteins bearing any of three single-amino-acid mutations present in the N-terminal portion of v-rel were sufficiently oncogenic to induce tumor development in the absence of additional mutations. (ii) Combining a mutation from the N-terminal region of v-rel with a deletion of the C-terminal sequences of c-rel increases the oncogenicity of the protein in an additive manner. (iii) Mutations present in the middle of v-rel cooperated synergistically with C-terminal deletions to produce highly transforming viruses. (iv) Deletion of c-rel produced a variety of transforming rel proteins with sizes that extended from 42 to 65 kDa. The most frequently isolated rel deletion was 62 kDa in size. To examine the basis for the selection of different rel mutants, their ability to induce immunoregulatory surface receptors was analyzed. The data revealed a correlation between the induction capacity of these mutants and

  8. Gene Expression Patterns of Hemizygous and Heterozygous KIT Mutations Suggest Distinct Oncogenic Pathways: A Study in NIH3T3 Cell Lines and GIST Samples

    PubMed Central

    Dessaux, Sophie; Besse, Anthony; Brahimi-Adouane, Sabrina; Emile, Jean-François; Blay, Jean-Yves; Alberti, Laurent

    2013-01-01

    Objective Most gain of function mutations of tyrosine kinase receptors in human tumours are hemizygous. Gastrointestinal stromal tumours (GIST) with homozygous mutations have a worse prognosis. We aimed to identify genes differentially regulated by hemizygous and heterozygous KIT mutations. Materials and Methods Expression of 94 genes and 384 miRNA was analysed with low density arrays in five NIH3T3 cell lines expressing the full-length human KIT cDNA wild-type (WT), hemizygous KIT mutation with del557-558 (D6) or del564-581 (D54) and heterozygous WT/D6 or WT/D54. Expression of 5 of these genes and 384 miRNA was then analysed in GISTs samples. Results Unsupervised and supervised hierarchical clustering of the mRNA and miRNA profiles showed that heterozygous mutants clustered with KIT WT expressing cells while hemizygous mutants were distinct. Among hemizygous cells, D6 and D54 expressing cells clustered separately. Most deregulated genes have been reported as potentially implicated in cancer and severals, as ANXA8 and FBN1, are highlighted by both, mRNA and miRNA analyses. MiRNA and mRNA analyses in GISTs samples confirmed that their expressions varied according to the mutation of the alleles. Interestingly, RGS16, a membrane protein of the regulator of G protein family, correlate with the subcellular localization of KIT mutants and might be responsible for regulation of the PI3K/AKT signalling pathway. Conclusion Patterns of mRNA and miRNA expression in cells and tumours depend on heterozygous/hemizygous status of KIT mutations, and deletion/presence of TYR568 & TYR570 residues. Thus each mutation of KIT may drive specific oncogenic pathways. PMID:23593401

  9. Impact of gsp oncogene on the expression of genes coding for Gsalpha, Pit-1, Gi2alpha, and somatostatin receptor 2 in human somatotroph adenomas: involvement in octreotide sensitivity.

    PubMed

    Barlier, A; Pellegrini-Bouiller, I; Gunz, G; Zamora, A J; Jaquet, P; Enjalbert, A

    1999-08-01

    The impact of the gsp oncogene on the expression of genes engaged in the somatotroph cell phenotype remains poorly understood in human somatotroph adenomas. As the gsp oncogene is associated with an increased octreotide (somatostatin agonist) sensitivity, a group of 8 somatotroph adenomas bearing the gsp mutation (gsp+) and another group of 16 adenomas without the mutation (gsp-) were analyzed, all of them presenting variable octreotide sensitivities. The expressions of genes encoding for G(s)alpha, Pit-1, G(i2)alpha, and SSTR2, involved in the regulation of secretory activity in somatotroph cells, were assessed by Northern blot. A decreased expression of the G(s)alpha gene was found in gsp + tumors, suggesting the existence of a negative feedback of the oncogenic protein upon its own messenger ribonucleic acid (mRNA). In contrast, G(i2)alpha, Pit-1, and GH messengers were not significantly different in the groups. A positive correlation between the in vitro and in vivo GH octreotide-induced secretory inhibition and the expression of SSTR2 mRNA was found. However, the expression of the gene for SSTR2 appeared not to be different between gsp + and gsp-, even when the octreotide sensitivity was significantly higher in the adenomas carrying the mutation. Interestingly, the SSTR2 gene expression was significantly correlated to those of G(i2)alpha and Pit-1. In the same way, the G(s)alpha mRNA expression was positively correlated with those of Gi2alpha and Pit-1. Such correlations strongly suggest a concerted dysregulation of the expression of these genes in both categories of adenomas. The loss of the octreotide sensitivity represents one aspect of the dysregulation process that partially results from the decreased SSTR2 expression. However, the improvement of the sensitivity associated with the presence of the gsp oncogene seems to proceed in a way different from SSTR2 expression.

  10. HER-2/neu oncogene amplification and chromosome 17 aneusomy in endometrial carcinoma: correlation with oncoprotein expression and conventional pathological parameters.

    PubMed

    Cianciulli, A M; Guadagni, F; Marzano, R; Benevolo, M; Merola, R; Giannarelli, D; Marandino, F; Vocaturo, G; Mariani, L; Mottolese, M

    2003-06-01

    The objective of the present study was to evaluate the correlation between HER-2 gene amplification and HER-2 protein overexpression in endometrial carcinoma using fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC). We also analyzed chromosome 17 aneusomy and the association between these biological parameters and conventional clinicopathological variables. FISH analysis was performed on 73 selected paraffin-embedded sections from endometrial carcinomas which previously had HER-2 status determined immunohistochemically using monoclonal antibodies (MoAb) 300G9 and CB11. Using a ratio of more than two oncogene signals/centromere to indicate amplification, a total of 42 out of the 73 endometrial tumors included in this study resulted positive by FISH where as protein overexpression was identified in 29 out of 73 with a concordance rate of 74.3%. However, when the mean signals/centromere per nucleus increased (ratio > 4 < or = 5) a higher concordance between the two assays was seen (p = 0.007). In addition, HER-2 amplification was significantly correlated with tumor stage (p = 0.021) and myometrial invasion (p = 0.010), whereas chromosome 17 polisomy showed a positive correlation only with myometrial invasion (p = 0.004) No significant correlation was found between HER-2 gene amplification, chromosome 17 aneusomy and patient outcome. Nevertheless, the probability of a 5 year overall survival decreased from 70% to 43%, respectively, for ratio > 2 < or = 4 and ratio > 4 < or = 5 when we grouped the amplified cases on the basis of HER-2:CEP17 ratio. In conclusion, molecular characteristics provide objective data that may be useful in predicting prognosis in patients with endometrial cancer.

  11. Merlin/NF2 functions upstream of the nuclear E3 ubiquitin ligase CRL4DCAF1 to suppress oncogenic gene expression.

    PubMed

    Cooper, Jonathan; Li, Wei; You, Liru; Schiavon, Gaia; Pepe-Caprio, Angela; Zhou, Lu; Ishii, Ryohei; Giovannini, Marco; Hanemann, C Oliver; Long, Stephen B; Erdjument-Bromage, Hediye; Zhou, Pengbo; Tempst, Paul; Giancotti, Filippo G

    2011-08-23

    Integrin-mediated activation of PAK (p21-activated kinase) causes phosphorylation and inactivation of the FERM (4.1, ezrin, radixin, moesin) domain-containing protein Merlin, which is encoded by the NF2 (neurofibromatosis type 2) tumor suppressor gene. Conversely, cadherin engagement inactivates PAK, thus leading to accumulation of unphosphorylated Merlin. Current models imply that Merlin inhibits cell proliferation by inhibiting mitogenic signaling at or near the plasma membrane. We have recently shown that the unphosphorylated, growth-inhibiting form of Merlin accumulates in the nucleus and binds to the E3 ubiquitin ligase CRL4(DCAF1) to suppress its activity. Depletion of DCAF1 blocks the hyperproliferation caused by inactivation of Merlin. Conversely, expression of a Merlin-insensitive DCAF1 mutant counteracts the antimitogenic effect of Merlin. Expression of Merlin or silencing of DCAF1 in Nf2-deficient cells induce an overlapping, tumor-suppressive program of gene expression. Mutations present in some tumors from NF2 patients disrupt Merlin's ability to interact with or inhibit CRL4(DCAF1). Lastly, depletion of DCAF1 inhibits the hyperproliferation of Schwannoma cells isolated from NF2 patients and suppresses the oncogenic potential of Merlin-deficient tumor cell lines. Current studies are aimed at identifying the substrates and mechanism of action of CRL4(DCAF1) and examining its role in NF2-dependent tumorigenesis in mouse models. We propose that Merlin mediates contact inhibition and suppresses tumorigenesis by translocating to the nucleus to inhibit CRL4(DCAF1).

  12. Oncogenic kinase NPM/ALK induces through STAT3 expression of immunosuppressive protein CD274 (PD-L1, B7-H1)

    PubMed Central

    Marzec, Michal; Zhang, Qian; Goradia, Ami; Raghunath, Puthiyaveettil N.; Liu, Xiaobin; Paessler, Michele; Wang, Hong Yi; Wysocka, Maria; Cheng, Mangeng; Ruggeri, Bruce A.; Wasik, Mariusz A.

    2008-01-01

    The mechanisms of malignant cell transformation caused by the oncogenic, chimeric nucleophosmin (NPM)/anaplastic lymphoma kinase (ALK) remain only partially understood, with most of the previous studies focusing mainly on the impact of NPM/ALK on cell survival and proliferation. Here we report that the NPM/ALK-carrying T cell lymphoma (ALK+TCL) cells strongly express the immunosuppressive cell-surface protein CD274 (PD-L1, B7-H1), as determined on the mRNA and protein level. The CD274 expression is strictly dependent on the expression and enzymatic activity of NPM/ALK, as demonstrated by inhibition of the NPM/ALK function in ALK+TCL cells by the small molecule ALK inhibitor CEP-14083 and by documenting CD274 expression in IL-3-depleted BaF3 cells transfected with the wild-type NPM/ALK, but not the kinase-inactive NPM/ALK K210R mutant or empty vector alone. NPM/ALK induces CD274 expression by activating its key signal transmitter, transcription factor STAT3. STAT3 binds to the CD274 gene promoter in vitro and in vivo, as shown in the gel electromobility shift and chromatin immunoprecipitation assays, and is required for the PD-L1 gene expression, as demonstrated by siRNA-mediated STAT3 depletion. These findings identify an additional cell-transforming property of NPM/ALK and describe a direct link between an oncoprotein and an immunosuppressive cell-surface protein. These results also provide an additional rationale to therapeutically target NPM/ALK and STAT3 in ALK+TCL. Finally, they suggest that future immunotherapeutic protocols for this type of lymphoma may need to include the inhibition of NPM/ALK and STAT3 to achieve optimal clinical efficacy. PMID:19088198

  13. Regulation of apoptosis by fau revealed by functional expression cloning and antisense expression.

    PubMed

    Mourtada-Maarabouni, Mirna; Kirkham, Lucy; Farzaneh, Farzin; Williams, Gwyn T

    2004-12-16

    Functional expression cloning is a powerful strategy for identifying critical steps in biological pathways independently of prior assumptions. It is particularly suitable for the identification of molecules crucial to the control of apoptosis. Our screen for sequences suppressing T-cell apoptosis isolated a sequence antisense to fau (Finkel-Biskis-Reilly murine sarcoma virus (FBR-MuSV)-associated ubiquitously expressed gene). The fox gene in FBR murine osteosarcoma virus is also antisense to fau and several reports have indicated that fau displays tumour suppressor and oncogenic properties in different contexts. Our observations indicate that the fau antisense sequence suppresses expression of endogenous fau mRNA and produces resistance to apoptosis induced both by the glucocorticoid analogue dexamethasone' by ultraviolet radiation, and by the anticancer drug cisplatin. In all cases, colony-forming ability is protected, indicating that fau affects the critical events prior to commitment to cell death. Overexpression of fau in the sense orientation induces cell death, which is inhibited both by Bcl-2 and by inhibition of caspases, in line with its proposed role in apoptosis.

  14. Automatic decoding of facial movements reveals deceptive pain expressions.

    PubMed

    Bartlett, Marian Stewart; Littlewort, Gwen C; Frank, Mark G; Lee, Kang

    2014-03-31

    In highly social species such as humans, faces have evolved to convey rich information for social interaction, including expressions of emotions and pain [1-3]. Two motor pathways control facial movement [4-7]: a subcortical extrapyramidal motor system drives spontaneous facial expressions of felt emotions, and a cortical pyramidal motor system controls voluntary facial expressions. The pyramidal system enables humans to simulate facial expressions of emotions not actually experienced. Their simulation is so successful that they can deceive most observers [8-11]. However, machine vision may be able to distinguish deceptive facial signals from genuine facial signals by identifying the subtle differences between pyramidally and extrapyramidally driven movements. Here, we show that human observers could not discriminate real expressions of pain from faked expressions of pain better than chance, and after training human observers, we improved accuracy to a modest 55%. However, a computer vision system that automatically measures facial movements and performs pattern recognition on those movements attained 85% accuracy. The machine system's superiority is attributable to its ability to differentiate the dynamics of genuine expressions from faked expressions. Thus, by revealing the dynamics of facial action through machine vision systems, our approach has the potential to elucidate behavioral fingerprints of neural control systems involved in emotional signaling.

  15. Tumorigenicity of simian virus 40-hepatocyte cell lines: effect of in vitro and in vivo passage on expression of liver-specific genes and oncogenes.

    PubMed Central

    Woodworth, C D; Kreider, J W; Mengel, L; Miller, T; Meng, Y L; Isom, H C

    1988-01-01

    Five simian virus 40 (SV40)-hepatocyte cell lines were examined for tumorigenicity and the effect of in vitro passage on the expression of four liver-specific genes (albumin, transferrin, alpha 1-antitrypsin, and phosphoenolpyruvate carboxykinase), two oncogenes (c-Ha-ras and c-raf), and two genes associated with hepatocarcinogenesis (alpha-fetoprotein and placental-type glutathione-S-transferase). At low passage (12 to 22), all five cell lines expressed the four liver-specific genes at levels similar to those in the liver and were not tumorigenic or were weakly tumorigenic. At high passage (33 to 61), the cell lines formed carcinomas, and four out of five cell lines produced primary tumors that metastasized. At least two cell lines produced well-differentiated hepatocellular carcinomas that expressed liver-specific RNAs. Levels of expression of liver-specific genes changed with time in culture. Some of the changes in liver-specific gene expression in the tumor tissue (such as for the phosphoenolpyruvate carboxykinase gene) paralleled those that occurred with in vitro passage, while other changes (such as for the albumin gene) did not parallel those that occurred with in vitro passage. Correlations between enhanced expression of c-Ha-ras and tumorigenic potential and between the process of SV40 immortalization and induced expression of c-raf and glutathione-S-transferase-P were observed. Induction of alpha-fetoprotein was detected with in vitro and in vivo passage only in the CWSV14 cell line and was paralleled by diminished albumin expression. In conclusion, we developed a model system with five SV40-hepatocyte cell lines, tumors induced by them, and tumor cell lines to examine changes in gene expression that accompany the progression from a normal cell to a hepatocellular carcinoma. Because the SV40-hepatocyte cell lines and tumor cell lines remain highly differentiated and vary in the magnitude of expression of specific genes, they can be used to study the

  16. Gene expression profiling of precursor T-cell lymphoblastic leukemia/lymphoma identifies oncogenic pathways that are potential therapeutic targets

    PubMed Central

    Lin, Ying-Wei; Aplan, Peter D.

    2007-01-01

    We compared the gene expression pattern of thymic tumors from precursor T-cell lymphoblastic lymphoma/leukemia (pre-T LBL) that arose in transgenic mice which over-expressed SCL, LMO1, or NUP98-HOXD13 (NHD13) with that of thymocytes from normal littermates. Only two genes, Ccl8 and Mrpl38, were consistently more than 4-fold over-expressed in pre-T LBL from all three genotypes analyzed, and a single gene, Prss16 was consistently under-expressed. However, we identified a number of genes, such as Cfl1, Tcra, Tcrb, Pbx3, Eif4a, Eif4b, and Cox8b that were over or under-expressed in pre-T LBL that arose in specific transgenic lines. Similar to the situation seen with human pre-T LBL, the SCL/LMO1 leukemias displayed an expression profile consistent with mature, late cortical thymocytes, whereas the NHD13 leukemias displayed an expression profile more consistent with immature thymocytes. We evaluated two of the most differentially regulated genes as potential therapeutic targets. Cfl1 was specifically over-expressed in SCL-LMO1 tumors; inactivation of Cfl1 using Okadaic acid resulted in suppression of leukemic cell growth. Overexpression of Ccl8 was a consistent finding in all 3 transgenic lines, and an antagonist for the Ccl8 receptor induced death of leukemic cell lines, suggesting a novel therapeutic approach. PMID:17429429

  17. A newly identified RET proto-oncogene polymorphism is found in a high number of endocrine tumor patients.

    PubMed

    Gartner, Wolfgang; Mineva, Ivelina; Daneva, Teodora; Baumgartner-Parzer, Sabina; Niederle, Bruno; Vierhapper, Heinrich; Weissel, Michael; Wagner, Ludwig

    2005-07-01

    Multiple RET proto-oncogene transcripts, due to genomic variations and alternate splicing, have been described. To investigate endocrine tumor tissue characteristic RET proto-oncogene expression, we performed quantitative RT-PCR, Northern blot and Southern blot analyses of benign and malignant endocrine-derived tissues. We newly describe RET proto-oncogene expression in carcinoid-, gastrinoma- and insulinoma-derived tissue samples. In addition, the presence of a 3'-terminally truncated RET proto-oncogene mRNA variant in benign and malignant thyroid neoplasias, as well as in a pheochromocytoma, an ovarian carcinoma and a medullary thyroid carcinoma, is demonstrated. Southern blot analysis revealed no evidence of gross RET proto-oncogene rearrangements or deletions. As the underlying cause for a bi-allelic TaqI restriction fragment length polymorphism (RFLP), a C (allele 1)/T (allele 2) transition within intron 19, was characterized. This polymorphism is close to a recently described polyadenylation site and lies within a binding site for the nucleic acid binding protein Pbx-1. Screening of healthy subjects and of patients suffering from various endocrine malignancies revealed exclusively allele 1 homozygous and allele 1/allele 2 heterozygous genotypes. Heterozygous genotypes were found in a significantly higher percentage in samples derived from endocrine tumor patients when compared with those from healthy control subjects. Homozygosity for allele 2 was found exclusively in somatic DNA derived from endocrine tumors with high malignant potential. Analysis of DNA derived from varying regions within individual anaplastic thyroid carcinomas revealed an allele 1/allele 2 switch of the RFLP banding pattern, indicating loss of heterozygosity at the RET proto-oncogene locus. In conclusion, our data demonstrate presence of a 5'-terminal RET proto-oncogene transcript in endocrine tissues and reveal a bi-allelic RET proto-oncogene polymorphism. A heterozygous genotype for

  18. Mutations in the nucleolar phosphoprotein, nucleophosmin, promote the expression of the oncogenic transcription factor MEF/ELF4 in leukemia cells and potentiates transformation.

    PubMed

    Ando, Koji; Tsushima, Hideki; Matsuo, Emi; Horio, Kensuke; Tominaga-Sato, Shinya; Imanishi, Daisuke; Imaizumi, Yoshitaka; Iwanaga, Masako; Itonaga, Hidehiro; Yoshida, Shinichiro; Hata, Tomoko; Moriuchi, Ryozo; Kiyoi, Hitoshi; Nimer, Stephen; Mano, Hiroyuki; Naoe, Tomoki; Tomonaga, Masao; Miyazaki, Yasushi

    2013-03-29

    Myeloid ELF1-like factor (MEF/ELF4), a member of the ETS transcription factors, can function as an oncogene in murine cancer models and is overexpressed in various human cancers. Here, we report a mechanism by which MEF/ELF4 may be activated by a common leukemia-associated mutation in the nucleophosmin gene. By using a tandem affinity purification assay, we found that MEF/ELF4 interacts with multifactorial protein nucleophosmin (NPM1). Coimmunoprecipitation and GST pull-down experiments demonstrated that MEF/ELF4 directly forms a complex with NPM1 and also identified the region of NPM1 that is responsible for this interaction. Functional analyses showed that wild-type NPM1 inhibited the DNA binding and transcriptional activity of MEF/ELF4 on the HDM2 promoter, whereas NPM1 mutant protein (Mt-NPM1) enhanced these activities of MEF/ELF4. Induction of Mt-NPM1 into MEF/ELF4-overexpressing NIH3T3 cells facilitated malignant transformation. In addition, clinical leukemia samples with NPM1 mutations had higher human MDM2 (HDM2) mRNA expression. Our data suggest that enhanced HDM2 expression induced by mutant NPM1 may have a role in MEF/ELF4-dependent leukemogenesis.

  19. Hidden among the crowd: differential DNA methylation-expression correlations in cancer occur at important oncogenic pathways

    PubMed Central

    Mosquera Orgueira, Adrián

    2015-01-01

    DNA methylation is a frequent epigenetic mechanism that participates in transcriptional repression. Variations in DNA methylation with respect to gene expression are constant, and, for unknown reasons, some genes with highly methylated promoters are sometimes overexpressed. In this study we have analyzed the expression and methylation patterns of thousands of genes in five groups of cancer and normal tissue samples in order to determine local and genome-wide differences. We observed significant changes in global methylation-expression correlation in all the neoplasms, which suggests that differential correlation events are frequent in cancer. A focused analysis in the breast cancer cohort identified 1662 genes whose correlation varies significantly between normal and cancerous breast, but whose DNA methylation and gene expression patterns do not change substantially. These genes were enriched in cancer-related pathways and repressive chromatin features across various model cell lines, such as PRC2 binding and H3K27me3 marks. Substantial changes in methylation-expression correlation indicate that these genes are subject to epigenetic remodeling, where the differential activity of other factors break the expected relationship between both variables. Our findings suggest a complex regulatory landscape where a redistribution of local and large-scale chromatin repressive domains at differentially correlated genes (DCGs) creates epigenetic hotspots that modulate cancer-specific gene expression. PMID:26029238

  20. Redox-modulating agents target NOX2-dependent IKKε oncogenic kinase expression and proliferation in human breast cancer cell lines

    PubMed Central

    Mukawera, Espérance; Chartier, Stefany; Williams, Virginie; Pagano, Patrick J.; Lapointe, Réjean; Grandvaux, Nathalie

    2015-01-01

    Oxidative stress is considered a causative factor in carcinogenesis, but also in the development of resistance to current chemotherapies. The appropriate usage of redox-modulating compounds is limited by the lack of knowledge of their impact on specific molecular pathways. Increased levels of the IKKε kinase, as a result of gene amplification or aberrant expression, are observed in a substantial number of breast carcinomas. IKKε not only plays a key role in cell transformation and invasiveness, but also in the development of resistance to tamoxifen. Here, we studied the effect of in vitro treatment with the redox-modulating triphenylmethane dyes, Gentian Violet and Brilliant Green, and nitroxide Tempol on IKKε expression and cell proliferation in the human breast cancer epithelial cell lines exhibiting amplification of IKKε, MCF-7 and ZR75.1. We show that Gentian Violet, Brilliant Green and Tempol significantly decrease intracellular superoxide anion levels and inhibit IKKε expression and cell viability. Treatment with Gentian Violet and Brilliant Green was associated with a reduced cyclin D1 expression and activation of caspase 3 and/or 7. Tempol decreased cyclin D1 expression in both cell lines, while activation of caspase 7 was only observed in MCF-7 cells. Silencing of the superoxide-generating NOX2 NADPH oxidase expressed in breast cancer cells resulted in the significant reduction of IKKε expression. Taken together, our results suggest that redox-modulating compounds targeting NOX2 could present a particular therapeutic interest in combination therapy against breast carcinomas exhibiting IKKε amplification. PMID:26177467

  1. Glycerophospholipid profile in oncogene-induced senescence.

    PubMed

    Cadenas, Cristina; Vosbeck, Sonja; Hein, Eva-Maria; Hellwig, Birte; Langer, Alice; Hayen, Heiko; Franckenstein, Dennis; Büttner, Bettina; Hammad, Seddik; Marchan, Rosemarie; Hermes, Matthias; Selinski, Silvia; Rahnenführer, Jörg; Peksel, Begüm; Török, Zsolt; Vígh, László; Hengstler, Jan G

    2012-09-01

    Alterations in lipid metabolism and in the lipid composition of cellular membranes are linked to the pathology of numerous diseases including cancer. However, the influence of oncogene expression on cellular lipid profile is currently unknown. In this work we analyzed changes in lipid profiles that are induced in the course of ERBB2-expression mediated premature senescence. As a model system we used MCF-7 breast cancer cells with doxycycline-inducible expression of NeuT, an oncogenic ERBB2 variant. Affymetrix gene array data showed NeuT-induced alterations in the transcription of many enzymes involved in lipid metabolism, several of which (ACSL3, CHPT1, PLD1, LIPG, MGLL, LDL and NPC1) could be confirmed by quantitative realtime PCR. A study of the glycerophospholipid and lyso-glycerophospholipid profiles, obtained by high performance liquid chromatography coupled to Fourier-transform ion cyclotron resonance-mass spectrometry revealed senescence-associated changes in numerous lipid species, including mitochondrial lipids. The most prominent changes were found in PG(34:1), PG(36:1) (increased) and LPE(18:1), PG(40:7) and PI(36:1) (decreased). Statistical analysis revealed a general trend towards shortened phospholipid acyl chains in senescence and a significant trend to more saturated acyl chains in the class of phosphatidylglycerol. Additionally, the cellular cholesterol content was elevated and accumulated in vacuoles in senescent cells. These changes were accompanied by increased membrane fluidity. In mitochondria, loss of membrane potential along with altered intracellular distribution was observed. In conclusion, we present a comprehensive overview of altered cholesterol and glycerophospholipid patterns in senescence, showing that predominantly mitochondrial lipids are affected and lipid species less susceptible to peroxidation are increased.

  2. Sparse expression bases in cancer reveal tumor drivers

    PubMed Central

    Logsdon, Benjamin A.; Gentles, Andrew J.; Miller, Chris P.; Blau, C. Anthony; Becker, Pamela S.; Lee, Su-In

    2015-01-01

    We define a new category of candidate tumor drivers in cancer genome evolution: ‘selected expression regulators’ (SERs)—genes driving dysregulated transcriptional programs in cancer evolution. The SERs are identified from genome-wide tumor expression data with a novel method, namely SPARROW (SPARse selected expRessiOn regulators identified With penalized regression). SPARROW uncovers a previously unknown connection between cancer expression variation and driver events, by using a novel sparse regression technique. Our results indicate that SPARROW is a powerful complementary approach to identify candidate genes containing driver events that are hard to detect from sequence data, due to a large number of passenger mutations and lack of comprehensive sequence information from a sufficiently large number of samples. SERs identified by SPARROW reveal known driver mutations in multiple human cancers, along with known cancer-associated processes and survival-associated genes, better than popular methods for inferring gene expression networks. We demonstrate that when applied to acute myeloid leukemia expression data, SPARROW identifies an apoptotic biomarker (PYCARD) for an investigational drug obatoclax. The PYCARD and obatoclax association is validated in 30 AML patient samples. PMID:25583238

  3. Exposure to diethylstilbestrol during pregnancy modulates microRNA expression profile in mothers and fetuses reflecting oncogenic and immunological changes.

    PubMed

    Singh, Narendra P; Abbas, Ikbal K; Menard, Martine; Singh, Udai P; Zhang, Jiajia; Nagarkatti, Prakash; Nagarkatti, Mitzi

    2015-05-01

    Prenatal exposure to diethylstilbestrol (DES) is known to cause an increased susceptibility to a wide array of clinical disorders in humans. Previous studies from our laboratory demonstrated that prenatal exposure to DES induces thymic atrophy and apoptosis in the thymus. In the current study, we investigated if such effects on the thymus result from alterations in the expression of microRNA (miR). To that end, pregnant C57BL/6 mice who were exposed to DES and miR profiles in thymocytes of both the mother and fetuses on postnatal day 3 (gestation day 17) were studied. Of the 609 mouse miRs examined, we noted 59 altered miRs that were common for both mothers and fetuses, whereas 107 altered miRs were specific to mothers only and 101 altered miRs were specific to fetuses only. Upon further analyses in the fetuses, we observed that DES-mediated changes in miR expression may regulate genes involved in important functions, such as apoptosis, autophagy, toxicity, and cancer. Of the miRs that showed decreased expression following DES treatment, miR-18b and miR-23a were found to possess complementary sequences and binding affinity for 3' untranslated regions of the Fas ligand (FasL) and Fas, respectively. Transfection studies confirmed that DES-mediated downregulation of miR-18b and miR-23a led to increased FasL and Fas expression. These data demonstrated that prenatal DES exposure can cause alterations in miRs, leading to changes in the gene expression, specifically, miR-mediated increased expression in FasL and Fas causing apoptosis and thymic atrophy.

  4. Proteomics profiling of Madin-Darby canine kidney plasma membranes reveals Wnt-5a involvement during oncogenic H-Ras/TGF-beta-mediated epithelial-mesenchymal transition.

    PubMed

    Chen, Yuan-Shou; Mathias, Rommel A; Mathivanan, Suresh; Kapp, Eugene A; Moritz, Robert L; Zhu, Hong-Jian; Simpson, Richard J

    2011-02-01

    Epithelial-mesenchymal transition (EMT) describes a process whereby polarized epithelial cells with restricted migration transform into elongated spindle-shaped mesenchymal cells with enhanced motility and invasiveness. Although there are some molecular markers for this process, including the down-regulation of E-cadherin, our understanding of plasma membrane (PM) and associated proteins involved in EMT is limited. To specifically explore molecular alterations occurring at the PM, we used the cationic colloidal silica isolation technique to purify PM fractions from epithelial Madin-Darby canine kidney cells during Ras/TGF-β-mediated EMT. Proteins in the isolated membrane fractions were separated by one-dimensional SDS-PAGE and subjected to nano-LC-MS/MS-based protein identification. In this study, the first membrane protein analysis of an EMT model, we identified 805 proteins and determined their differential expression using label-free spectral counting. These data reveal that Madin-Darby canine kidney cells switch from cadherin-mediated to integrin-mediated adhesion following Ras/TGF-β-mediated EMT. Thus, during the EMT process, E-cadherin, claudin 4, desmoplakin, desmoglein-2, and junctional adhesion molecule A were down-regulated, whereas integrins α6β1, α3β1, α2β1, α5β1, αVβ1, and αVβ3 along with their extracellular ligands collagens I and V and fibronectin had increased expression levels. Conspicuously, Wnt-5a expression was elevated in cells undergoing EMT, and transient Wnt-5a siRNA silencing attenuated both cell migration and invasion in these cells. Furthermore, Wnt-5a expression suppressed canonical Wnt signaling induced by Wnt-3a. Wnt-5a may act through the planar cell polarity pathway of the non-canonical Wnt signaling pathway as several of the components and modulators (Wnt-5a, -5b, frizzled 6, collagen triple helix repeat-containing protein 1, tyrosine-protein kinase 7, RhoA, Rac, and JNK) were found to be up-regulated during Ras

  5. Ectopic over-expression of oncogene Pim-2 induce malignant transformation of nontumorous human liver cell line L02.

    PubMed

    Ren, Ke; Duan, Wentao; Shi, Yujun; Li, Bo; Liu, Zuojin; Gong, Jiangping

    2010-07-01

    In order to prove that ectopic over-expression of Pim-2 could induce malignant transformation of human liver cell line L02, three groups of cells were set up including human liver cell line L02 (L02), L02 cells transfected with Pim-2 gene (L02/Pim-2) and L02 cells transfected with empty-vector (L02/Vector). Pim-2 expression levels were detected. The morphology, proliferation level, apoptosis rate and migration ability of the cells were detected respectively. Then the cells were subcutaneously inoculated into athymic mice and the microstructures of the neoplasm were observed. Compared with the controls, Pim-2 expression levels were significantly higher in L02/Pim-2 cells (P<0.05), and their morphology had obvious malignant changes. They also showed a significantly increased proliferation rate (P<0.05) and migration capacity (P<0.05), as well as a significantly decreased apoptosis rate (P<0.05). Only the athymic mice inoculated with L02/Pim-2 cells could generate neoplasm, and the morphology of the neoplasm coincided with that of the hepatoma. The results manifest that ectopic Pim-2 gene could be stably expressed in L02/Pim-2 cells. Both the morphological and biological changes of L02/Pim-2 cells demonstrate the trend of malignant transformation. L02/Pim-2 cells could generate hepatoma in athymic mice. In conclusion, Pim-2 could induce malignant transformation of human liver cell line L02.

  6. ERMP1, a novel potential oncogene involved in UPR and oxidative stress defense, is highly expressed in human cancer

    PubMed Central

    Grandi, Alberto; Santi, Alice; Campagnoli, Susanna; Parri, Matteo; De Camilli, Elisa; Song, Chaojun; Jin, Boquan; Lacombe, Aurelien; Castori-Eppenberger, Serenella; Sarmientos, Paolo; Grandi, Guido; Viale, Giuseppe; Terracciano, Luigi; Chiarugi, Paola; Pileri, Piero; Grifantini, Renata

    2016-01-01

    Endoplasmic reticulum (ER) stress and unfolded protein response (UPR) are highly activated in cancer and involved in tumorigenesis and resistance to anti-cancer therapy. UPR is becoming a promising target of anti-cancer therapies. Thus, the identification of UPR components that are highly expressed in cancer could offer new therapeutic opportunity. In this study, we demonstrate that Endoplasmic Reticulum Metallo Protease 1 (ERMP1) is broadly expressed in a high percentage of breast, colo-rectal, lung, and ovary cancers, regardless of their stage and grade. Moreover, we show that loss of ERMP1 expression significantly hampers proliferation, migration and invasiveness of cancer cells. Furthermore, we show that this protein is an important player in the UPR and defense against oxidative stress. ERMP1 expression is strongly affected by reticular stress induced by thapsigargin and other oxidative stresses. ERMP1 silencing during reticular stress impairs the activation of PERK, a key sensor of the UPR activation. Loss of ERMP1 also prevents the expression of GRP78/BiP, a UPR stress marker involved in the activation of the survival pathway. Finally, ERMP1 silencing in cells exposed to hypoxia leads to inhibition of the Nrf2-mediated anti-oxidant response and to reduction of accumulation of HIF-1, the master transcription factor instructing cells to respond to hypoxic stress. Our results suggest that ERMP1 could act as a molecular starter to the survival response induced by extracellular stresses. Moreover, they provide the rationale for the design of ERMP1-targeting drugs that could act by inhibiting the UPR initial adaptive response of cancer cells and impair cell survival. PMID:27566589

  7. SIRT1 inhibits proliferation of pancreatic cancer cells expressing pancreatic adenocarcinoma up-regulated factor (PAUF), a novel oncogene, by suppression of {beta}-catenin

    SciTech Connect

    Cho, Il-Rae; Koh, Sang Seok; Malilas, Waraporn; Srisuttee, Ratakorn; Moon, Jeong; Choi, Young-Whan; Horio, Yoshiyuki; Oh, Sangtaek; Chung, Young-Hwa

    2012-06-29

    Highlights: Black-Right-Pointing-Pointer SIRT1 inhibits protein levels of {beta}-catenin and its transcriptional activity. Black-Right-Pointing-Pointer Nuclear localization of SIRT1 is not required for the decrease of {beta}-catenin expression. Black-Right-Pointing-Pointer SIRT1-mediated degradation of {beta}-catenin is not required for GSK-3{beta} and Siah-1 but for proteosome. Black-Right-Pointing-Pointer SIRT1 activation inhibits proliferation of pancreatic cancer cells expressing PAUF. -- Abstract: Because we found in a recent study that pancreatic adenocarcinoma up-regulated factor (PAUF), a novel oncogene, induces a rapid proliferation of pancreatic cells by up-regulation of {beta}-catenin, we postulated that {beta}-catenin might be a target molecule for pancreatic cancer treatment. We thus speculated whether SIRT1, known to target {beta}-catenin in a colon cancer model, suppresses {beta}-catenin in those pancreatic cancer cells that express PAUF (Panc-PAUF). We further evaluated whether such suppression would lead to inhibition of the proliferation of these cells. The ectopic expression of either SIRT1 or resveratrol (an activator of SIRT1) suppressed levels of {beta}-catenin protein and its transcriptional activity in Panc-PAUF cells. Conversely, suppression of SIRT1 expression by siRNA enhanced {beta}-catenin expression and transcriptional activity. SIRT1 mutant analysis showed that nuclear localization of SIRT1 is not required for reduction of {beta}-catenin. Treatment with MG132, a proteasomal inhibitor, restored {beta}-catenin protein levels, suggesting that SIRT1-mediated degradation of {beta}-catenin requires proteasomal activity. It was reported that inhibition of GSK-3{beta} or Siah-1 stabilizes {beta}-catenin in colon cancer cells, but suppression of GSK-3{beta} or Siah-1 using siRNA in the presence of resveratrol instead diminished {beta}-catenin protein levels in Panc-PAUF cells. This suggests that GSK-3{beta} and Siah-1 are not involved in SIRT1

  8. What Facial Appearance Reveals Over Time: When Perceived Expressions in Neutral Faces Reveal Stable Emotion Dispositions

    PubMed Central

    Adams, Reginald B.; Garrido, Carlos O.; Albohn, Daniel N.; Hess, Ursula; Kleck, Robert E.

    2016-01-01

    It might seem a reasonable assumption that when we are not actively using our faces to express ourselves (i.e., when we display nonexpressive, or neutral faces), those around us will not be able to read our emotions. Herein, using a variety of expression-related ratings, we examined whether age-related changes in the face can accurately reveal one’s innermost affective dispositions. In each study, we found that expressive ratings of neutral facial displays predicted self-reported positive/negative dispositional affect, but only for elderly women, and only for positive affect. These findings meaningfully replicate and extend earlier work examining age-related emotion cues in the face of elderly women (Malatesta et al., 1987a). We discuss these findings in light of evidence that women are expected to, and do, smile more than men, and that the quality of their smiles predicts their life satisfaction. Although ratings of old male faces did not significantly predict self-reported affective dispositions, the trend was similar to that found for old female faces. A plausible explanation for this gender difference is that in the process of attenuating emotional expressions over their lifetimes, old men reveal less evidence of their total emotional experiences in their faces than do old women. PMID:27445944

  9. Small genomic insertions form enhancers that misregulate oncogenes

    PubMed Central

    Abraham, Brian J.; Hnisz, Denes; Weintraub, Abraham S.; Kwiatkowski, Nicholas; Li, Charles H.; Li, Zhaodong; Weichert-Leahey, Nina; Rahman, Sunniyat; Liu, Yu; Etchin, Julia; Li, Benshang; Shen, Shuhong; Lee, Tong Ihn; Zhang, Jinghui; Look, A. Thomas; Mansour, Marc R.; Young, Richard A.

    2017-01-01

    The non-coding regions of tumour cell genomes harbour a considerable fraction of total DNA sequence variation, but the functional contribution of these variants to tumorigenesis is ill-defined. Among these non-coding variants, somatic insertions are among the least well characterized due to challenges with interpreting short-read DNA sequences. Here, using a combination of Chip-seq to enrich enhancer DNA and a computational approach with multiple DNA alignment procedures, we identify enhancer-associated small insertion variants. Among the 102 tumour cell genomes we analyse, small insertions are frequently observed in enhancer DNA sequences near known oncogenes. Further study of one insertion, somatically acquired in primary leukaemia tumour genomes, reveals that it nucleates formation of an active enhancer that drives expression of the LMO2 oncogene. The approach described here to identify enhancer-associated small insertion variants provides a foundation for further study of these abnormalities across human cancers. PMID:28181482

  10. Function of oncogenes in cancer development: a changing paradigm

    PubMed Central

    Vicente-Dueñas, Carolina; Romero-Camarero, Isabel; Cobaleda, Cesar; Sánchez-García, Isidro

    2013-01-01

    Tumour-associated oncogenes induce unscheduled proliferation as well as genomic and chromosomal instability. According to current models, therapeutic strategies that block oncogene activity are likely to selectively target tumour cells. However, recent evidences have revealed that oncogenes are only essential for the proliferation of some specific tumour cell types, but not all. Indeed, the latest studies of the interactions between the oncogene and its target cell have shown that oncogenes contribute to cancer development not only by inducing proliferation but also by developmental reprogramming of the epigenome. This provides the first evidence that tumorigenesis can be initiated by stem cell reprogramming, and uncovers a new role for oncogenes in the origin of cancer. Here we analyse these evidences and propose an updated model of oncogene function that can explain the full range of genotype–phenotype associations found in human cancer. Finally, we discuss how this vision opens new avenues for developing novel anti-cancer interventions. PMID:23632857

  11. Multi-focal control of mitochondrial gene expression by oncogenic MYC provides potential therapeutic targets in cancer

    PubMed Central

    Oran, Amanda R.; Adams, Clare M.; Zhang, Xiao-yong; Gennaro, Victoria J.; Pfeiffer, Harla K.; Mellert, Hestia S.; Seidel, Hans E.; Mascioli, Kirsten; Kaplan, Jordan; Gaballa, Mahmoud R.; Shen, Chen; Rigoutsos, Isidore; King, Michael P.; Cotney, Justin L.; Arnold, Jamie J.; Sharma, Suresh D.; Martinez, Ubaldo E.; Vakoc, Christopher R.; Chodosh, Lewis A.; Thompson, James E.; Bradner, James E.; Cameron, Craig E.; Shadel, Gerald S.; Eischen, Christine M.; McMahon, Steven B.

    2016-01-01

    Despite ubiquitous activation in human cancer, essential downstream effector pathways of the MYC transcription factor have been difficult to define and target. Using a structure/function-based approach, we identified the mitochondrial RNA polymerase (POLRMT) locus as a critical downstream target of MYC. The multifunctional POLRMT enzyme controls mitochondrial gene expression, a process required both for mitochondrial function and mitochondrial biogenesis. We further demonstrate that inhibition of this newly defined MYC effector pathway causes robust and selective tumor cell apoptosis, via an acute, checkpoint-like mechanism linked to aberrant electron transport chain complex assembly and mitochondrial reactive oxygen species (ROS) production. Fortuitously, MYC-dependent tumor cell death can be induced by inhibiting the mitochondrial gene expression pathway using a variety of strategies, including treatment with FDA-approved antibiotics. In vivo studies using a mouse model of Burkitt's Lymphoma provide pre-clinical evidence that these antibiotics can successfully block progression of MYC-dependent tumors. PMID:27590350

  12. The Dioxin Receptor Regulates the Constitutive Expression of the Vav3 Proto-Oncogene and Modulates Cell Shape and Adhesion

    PubMed Central

    Carvajal-Gonzalez, Jose M.; Mulero-Navarro, Sonia; Roman, Angel Carlos; Sauzeau, Vincent; Merino, Jaime M.; Bustelo, Xose R.

    2009-01-01

    The dioxin receptor (AhR) modulates cell plasticity and migration, although the signaling involved remains unknown. Here, we report a mechanism that integrates AhR into these cytoskeleton-related functions. Immortalized and mouse embryonic fibroblasts lacking AhR (AhR−/−) had increased cell area due to spread cytoplasms that reverted to wild-type morphology upon AhR re-expression. The AhR-null phenotype included increased F-actin stress fibers, depolarized focal adhesions, and enhanced spreading and adhesion. The cytoskeleton alterations of AhR−/− cells were due to down-regulation of constitutive Vav3 expression, a guanosine diphosphate/guanosine triphosphate exchange factor for Rho/Rac GTPases and a novel transcriptional target of AhR. AhR was recruited to the vav3 promoter and maintained constitutive mRNA expression in a ligand-independent manner. Consistently, AhR−/− fibroblasts had reduced Rac1 activity and increased activation of the RhoA/Rho kinase (Rock) pathway. Pharmacological inhibition of Rac1 shifted AhR+/+ fibroblasts to the null phenotype, whereas Rock inhibition changed AhR-null cells to the AhR+/+ morphology. Knockdown of vav3 transcripts by small interfering RNA induced cytoskeleton defects and changes in adhesion and spreading mimicking those of AhR-null cells. Moreover, vav3−/− MEFs, as AhR−/− mouse embryonic fibroblasts, had increased cell area and enhanced stress fibers. By modulating Vav3-dependent signaling, AhR could regulate cell shape, adhesion, and migration under physiological conditions and, perhaps, in certain pathological states. PMID:19158396

  13. Genome-Wide Gene Expression Analysis Identifies the Proto-oncogene Tyrosine-Protein Kinase Src as a Crucial Virulence Determinant of Infectious Laryngotracheitis Virus in Chicken Cells

    PubMed Central

    Li, Hai; Wang, Fengjie; Han, Zongxi; Gao, Qi; Li, Huixin; Shao, Yuhao; Sun, Nana

    2015-01-01

    ABSTRACT Given the side effects of vaccination against infectious laryngotracheitis (ILT), novel strategies for ILT control and therapy are urgently needed. The modulation of host-virus interactions is a promising strategy to combat the virus; however, the interactions between the host and avian ILT herpesvirus (ILTV) are unclear. Using genome-wide transcriptome studies in combination with a bioinformatic analysis, we identified proto-oncogene tyrosine-protein kinase Src (Src) to be an important modulator of ILTV infection. Src controls the virulence of ILTV and is phosphorylated upon ILTV infection. Functional studies revealed that Src prolongs the survival of host cells by increasing the threshold of virus-induced cell death. Therefore, Src is essential for viral replication in vitro and in ovo but is not required for ILTV-induced cell death. Furthermore, our results identify a positive-feedback loop between Src and the tyrosine kinase focal adhesion kinase (FAK), which is necessary for the phosphorylation of either Src or FAK and is required for Src to modulate ILTV infection. To the best of our knowledge, we are the first to identify a key host regulator controlling host-ILTV interactions. We believe that our findings have revealed a new potential therapeutic target for ILT control and therapy. IMPORTANCE Despite the extensive administration of live attenuated vaccines starting from the mid-20th century and the administration of recombinant vaccines in recent years, infectious laryngotracheitis (ILT) outbreaks due to avian ILT herpesvirus (ILTV) occur worldwide annually. Presently, there are no drugs or control strategies that effectively treat ILT. Targeting of host-virus interactions is considered to be a promising strategy for controlling ILTV infections. However, little is known about the mechanisms governing host-ILTV interactions. The results from our study advance our understanding of host-ILTV interactions on a molecular level and provide experimental

  14. Proto-oncogene ACTR/AIB1 promotes cancer cell invasion by up-regulating specific matrix metalloproteinase expression.

    PubMed

    Li, Li B; Louie, Maggie C; Chen, H-W; Zou, June X

    2008-03-08

    Overexpression of ACTR/AIB1 is frequently found in different cancers with distant metastasis. To address its possible involvement in tumor metastasis, we performed invasion assays to examine the effect of ACTR alteration on the invasiveness of breast cancer cells (MDA-MB-231 or T-47D) and found that high levels of ACTR are required for their strong invasiveness. Molecular analysis indicates that ACTR functions as a coactivator of AP-1 to up-regulate the expression of matrix metalloproteinases such as MMP-7 and MMP-10 and reduce cell adhesion to specific extracellular matrix proteins. These novel findings provide a mechanistic link between ACTR and MMPs, and suggest that ACTR may also play an important role in cancer progression by facilitating tumor invasion.

  15. Effect of Helicobacter pylori infection and its eradication on cell proliferation, DNA status, and oncogene expression in patients with chronic gastritis

    PubMed Central

    Nardone, G; Staibano, S; Rocco, A; Mezza, E; D'Armiento, F; Insabato, L; Coppola, A; Salvatore, G; Lucariello, A; Figura, N; De Rosa, G; Budillon, G

    1999-01-01

    BACKGROUND—Helicobacter pylori, the main cause of chronic gastritis, is a class I gastric carcinogen. Chronic gastritis progresses to cancer through atrophy, metaplasia, and dysplasia. Precancerous phenotypic expression is generally associated with acquired genomic instability.
AIM—To evaluate the effect of H pylori infection and its eradication on gastric histology, cell proliferation, DNA status, and oncogene expression.
METHODS/SUBJECTS—Morphometric and immunohistochemical techniques were used to examine gastric mucosal biopsy specimens from eight controls, 10 patients with H pylori negative chronic gastritis, 53 with H pylori positive chronic gastritis, and 11 with gastric cancer.
RESULTS—All patients with chronic gastritis were in a hyperproliferative state related to mucosal inflammation, regardless of H pylori infection. Atrophy was present in three of 10 patients with H pylori negative chronic gastritis and in 26 of 53 with H pylori positive chronic gastritis, associated in 18 with intestinal metaplasia. DNA content was abnormal in only 11 patients with atrophy and H pylori infection; eight of these also had c-Myc expression, associated in six cases with p53 expression. Fifty three patients with H pylori positive chronic gastritis were monitored for 12 months after antibiotic treatment: three dropped out; infection was eradicated in 45, in whom cell proliferation decreased in parallel with the reduction in gastritis activity; atrophy previously detected in 21/45 disappeared in five, regressed from moderate to mild in nine, and remained unchanged in seven; complete metaplasia disappeared in 4/14, and markers of genomic instability disappeared where previously present. In the five patients in whom H pylori persisted, atrophy, metaplasia, dysplasia, and markers of genomic instability remained unchanged.
CONCLUSIONS—Chronic H pylori infection seems to be responsible for genomic instability in a subset of cases of H pylori positive

  16. Inhibition of MEK5 by BIX02188 induces apoptosis in cells expressing the oncogenic mutant FLT3-ITD

    SciTech Connect

    Razumovskaya, Elena; Sun, Jianmin; Roennstrand, Lars

    2011-08-26

    Highlights: {yields} In this study we have demonstrated that FLT3 activation leads to activation of ERK5. {yields} We have demonstrated that ERK5 is involved in activation of AKT downstream of FLT3. {yields} (BIX02188) blocks activation of ERK5 and induces apoptosis in FLT3 Ba/F3 cells. {yields} (BIX02188) induce apoptosis in the two leukemic cell lines MV4-11 and MOLM-13. -- Abstract: Fms-like tyrosine kinase-3 (FLT3) is a growth factor receptor normally expressed on hematopoietic progenitor cells. Approximately one third of all patients with AML carry an activating mutation in FLT3 that drives proliferation and survival of the leukemic cells. The most common activating mutation is the so-called internal tandem duplication (ITD), which involves an in-frame duplication of a segment of varying length in the region of the FLT3 gene that encodes the juxtamembrane domain. The pathways downstream of FLT3-ITD are partially known but further knowledge regarding the downstream signal transduction molecules is important in order to develop alternative strategies for pharmacological intervention. In this paper we have studied the role of MEK/ERK5 in FLT3-ITD mediated transformation. We have found that both wild-type FLT3 and FLT3-ITD activate MEK5 leading to the activation of ERK5. By use of the selective inhibitor of MEK5, (BIX02188), we have shown that activation of AKT downstream of FLT3 is partially dependent on ERK5. Furthermore, inhibition of MEK5/ERK5 induces apoptosis of both FLT3-ITD transfected Ba/F3 cells as well as the FLT3-ITD carrying leukemic cell lines MV4-11 and MOLM-13. These results suggest that MEK5/ERK5 is important for FLT3-ITD induced hematopoietic transformation and may thus represent an alternative therapeutic target in the treatment of FLT3-ITD positive leukemia.

  17. Phenotypic Expression in Wheat Revealed Using FT-IR Microspectroscopy

    SciTech Connect

    Brewer, L.; Wetzel, D

    2009-01-01

    Wheat selected for cultivation through the centuries has a glume that is 'soft' instead of 'tough' as naturally occurring. In production, this is desirable because it enables mechanical threshing with efficient separation of kernel from the head of each stalk without damaging the kernel. FT-IR microspectroscopy provides chemically based, objective assessment of genetic expression by measuring the extent of genetic expression. In the Microbeam Molecular Spectroscopy Laboratory, Manhattan, KS, an imaging FT-IR microspectrometer with a detector array focused on the image plane was used to obtain spectral data from dissected glume specimens of nine tough and eleven soft wheat cultivars in a rectangular mapping pattern. With cellulose as the substrate, the extent of lignification is measurable from the ratio of the lignin (1508 cm{sup -1}) baseline adjusted band area to the representative cellulosic (1370 cm{sup -1}) band area. A distinction between soft and tough glumes is obtained in numerical terms. Using a band ratio minimizes variation due to thickness differences. While analyzing mapped sections of glume, care is taken to avoid tabulation of spectral data from vascular bundles. Inclusion of these data would to avoid tabulation of spectral data from vascular bundles. Inclusion of these data would bias the analysis toward the composition of highly lignified vascular bundles. Spatially resolved focal plane array FT-IR microspectroscopy reveals the extent of glume lignification that is coincident with the toughness trait. This enables breeders to rank the degree of lignin expression and discriminate between soft and tough breeding results.

  18. Regulation of Na+-H+ exchange in normal NIH-3T3 cells and in NIH-3T3 cells expressing the ras oncogene

    SciTech Connect

    Owen, N.E.; Knapik, J.; Strebel, F.; Tarpley, W.G.; Gorman, R.R.

    1989-04-01

    Our laboratory and others have demonstrated that Na+-H+ exchange can be regulated by two different pathways; one that is mediated by an inositol trisphosphate-stimulated increase in intracellular calcium activity, and one that is mediated by an increase in protein kinase C activity. To determine whether one of these pathways is more important than the other, or whether one pathway is physiologically relevant, we employed normal NIH-3T3 cells (3T3 cells) and NIH-3T3 cells expressing the EJ human bladder ras oncogene (EJ cells). The EJ cells were chosen because they provide a genetic model that does not exhibit serum- or platelet-derived growth factor (PDGF)-stimulated inositol trisphosphate release or Ca2+ mobilization. It was found that serum- or PDGF-stimulated Na+-H+ exchange was more pronounced in EJ cells than in control 3T3 cells. As expected, serum- or PDGF-stimulated Na+-H+ exchange in 3T3 cells was inhibited by chelating intracellular Ca2+ with the intracellular Ca2+ chelator quin2, by the intracellular Ca2+ antagonist 8-(N,N-diethylamino)octyl 3,4,5-trimethoxybenzoate (TMB-8), and by the calmodulin antagonist trifluoperazine. In contrast, these agents did not inhibit serum- or PDGF-stimulated Na+-H+ exchange in EJ cells. Activators of protein kinase C (e.g., 1-oleoyl-2-acetylglycerol or biologically active phorbol esters) were found to stimulate Na+-H+ exchange in EJ cells to the same extent as serum. However, these agents were considerably less effective than serum in control 3T3 cells. Despite these findings, PDGF did not stimulate diacylglycerol levels in EJ cells.

  19. Loss of platelet-derived growth factor-stimulated phospholipase activity in NIH-3T3 cells expressing the EJ-ras oncogene

    SciTech Connect

    Benjamin, C.W.; Tarpley, W.G.; Gorman, R.R.

    1987-01-01

    Data indicating that the 21-kDa protein (p21) Harvey-ras gene product shares sequence homology with guanine nucleotide-binding proteins (G proteins) has stimulated research on the influence(s) of p21 on G-protein-regulated systems in vertebrate cells. Previous work demonstrated that NIH-3T3 mouse cells expressing high levels of the cellular ras oncogene isolated from the EJ human bladder carcinoma (EJ-ras) exhibited reduced hormone-stimulated adenylate cyclase activity. The authors now report that in these cells another enzyme system thought to be regulated by G proteins is inhibited, namely phospholipases A/sub 2/ and C. NIH-3T3 cells incubated in plasma-derived serum release significant levels of prostaglandin E/sub 2/ (PGE/sub 2/) as determined by radioimmunoassay when exposed to platelet-derived growth factor (PDGF) at 2 units/ml. The lack of PDGF-stimulated PGE/sub 2/ release from EJ-ras-transfected cells is not due to a defect in the prostaglandin cyclooxygenase enzyme, since incubation of control cells and EJ-ras-transfected cells in 0.33, 3.3, or 33 ..mu..M arachidonate resulted in identical levels of PGE/sub 2/ release. The lack of PDGF-stimulated PGE/sub 2/ release from EJ-ras-transfected cells also does not result from the loss of functional PDGF receptors. EJ-ras-transformed cells bind 70% as much /sup 125/I-labeled PDGF as control cells and are stimulated to incorporate (/sup 3/H)thymidine and to proliferate after exposure to PDGF. Determination of total water-soluble inositolphospholipids and changes in the specific activities of phosphatidylcholine in control and EJ-ras-transfected cells demonstrated that PDGF-stimulated phospholipase C and A/sub 2/ activities are inhibited in the EJ-ras-transfected cells.

  20. Enhanced expression of Ca2+ channels by nerve growth factor and the v-src oncogene in rat phaeochromocytoma cells.

    PubMed Central

    Lewis, D L; De Aizpurua, H J; Rausch, D M

    1993-01-01

    1. Rat phaeochromocytoma (PC12) cells were used to investigate the expression of Ca2+ channel types during neuronal differentiation. Neuronal differentiation was induced by treatment with nerve growth factor (NGF) or by activation of a temperature-sensitive tyrosine kinase (pp60v-src) in genetically modified PC12 (PC12/v-src) cells. PC12 cells differentiated morphologically in the presence of NGF. When grown at the permissive temperature of 37 degrees C which activates the kinase activity of pp60v-src, PC12/v-src cells differentiated morphologically with the extension of neurites. In contrast, PC12/v-src cells grown at the non-permissive temperature of 40 degrees C continued to divide and were morphologically indistinguishable from control PC12 cells. 2. Whole-cell Ca2+ currents were measured in PC12 cells using Ba2+ as the charge carrier. Ba2+ currents measured at the peak of the current-voltage curve from a holding potential of -80 mV were -0.28 +/- 0.04 nA (mean +/- S.E.M.) in control PC12 cells compared to -1.25 +/- 0.16 nA in NGF-differentiated cells. The current density increased from 9.4 +/- 0.7 pA/pF in control PC12 cells to 22.8 +/- 2.4 pA/pF in NGF-differentiated PC12 cells. Ba2+ currents were -0.24 +/- 0.04 nA in undifferentiated PC12/v-src cells grown at the non-permissive temperature of 40 degrees C compared to -0.95 +/- 0.16 nA in differentiated PC12/v-src cells grown at the permissive temperature of 37 degrees C. The current density increased from 4.5 +/- 0.5 pA/pF in PC12/v-src cells grown at the non-permissive temperature of 40 degrees C to 13.3 +/- 2.4 pA/pF in PC12/v-src cells grown at the permissive temperature of 37 degrees C. 3. The sensitivity of Ba2+ currents to omega-conotoxin GVIA (omega-CgTX) was determined for currents measured at the peak of the current-voltage curve (0 mV in 10 mM Ba2+) from a holding potential of -80 mV. In NGF-differentiated PC12 cells, 10 microM omega-CgTx inhibited 68.1 +/- 3.2% of the total Ba2+ current compared

  1. Oncogenic KRAS triggers MAPK-dependent errors in mitosis and MYC-dependent sensitivity to anti-mitotic agents

    PubMed Central

    Perera, David; Venkitaraman, Ashok R.

    2016-01-01

    Oncogenic KRAS induces cell proliferation and transformation, but little is known about its effects on cell division. Functional genetic screens have recently revealed that cancer cell lines expressing oncogenic KRAS are sensitive to interference with mitosis, but neither the mechanism nor the uniformity of anti-mitotic drug sensitivity connected with mutant KRAS expression are yet clear. Here, we report that acute expression of oncogenic KRAS in HeLa cells induces mitotic delay and defects in chromosome segregation through mitogen-activated protein kinase (MAPK) pathway activation and de-regulated expression of several mitosis-related genes. These anomalies are accompanied by increased sensitivity to anti-mitotic agents, a phenotype dependent on the transcription factor MYC and its downstream target anti-apoptotic protein BCL-XL. Unexpectedly, we find no correlation between KRAS mutational status or MYC expression levels and anti-mitotic drug sensitivity when surveying a large database of anti-cancer drug responses. However, we report that the co-existence of KRAS mutations and high MYC expression predicts anti-mitotic drug sensitivity. Our findings reveal a novel function of oncogenic KRAS in regulating accurate mitotic progression and suggest new avenues to therapeutically target KRAS-mutant tumours and stratify patients in ongoing clinical trials of anti-mitotic drugs. PMID:27412232

  2. Analysis of wntless (WLS) expression in gastric, ovarian, and breast cancers reveals a strong association with HER2 overexpression.

    PubMed

    Stewart, Jonathan; James, Jacqueline; McCluggage, Glenn W; McQuaid, Stephen; Arthur, Kenneth; Boyle, David; Mullan, Paul; McArt, Darragh; Yan, Benedict; Irwin, Gareth; Harkin, D Paul; Zhengdeng, Lei; Ong, Chee-Wee; Yu, Jia; Virshup, David M; Salto-Tellez, Manuel

    2015-03-01

    The oncogenic role of WNT is well characterized. Wntless (WLS) (also known as GPR177, or Evi), a key modulator of WNT protein secretion, was recently found to be highly overexpressed in malignant astrocytomas. We hypothesized that this molecule may be aberrantly expressed in other cancers known to possess aberrant WNT signaling such as ovarian, gastric, and breast cancers. Immunohistochemical analysis using a TMA platform revealed WLS overexpression in a subset of ovarian, gastric, and breast tumors; this overexpression was associated with poorer clinical outcomes in gastric cancer (P=0.025). In addition, a strong correlation was observed between WLS expression and human epidermal growth factor receptor 2 (HER2) overexpression. Indeed, 100% of HER2-positive intestinal gastric carcinomas, 100% of HER2-positive serous ovarian carcinomas, and 64% of HER2-positive breast carcinomas coexpressed WLS protein. Although HER2 protein expression or gene amplification is an established predictive biomarker for trastuzumab response in breast and gastric cancers, a significant proportion of HER2-positive tumors display resistance to trastuzumab, which may be in part explainable by a possible mechanistic link between WLS and HER2.

  3. EWS/FLI-1 silencing and gene profiling of Ewing cells reveal downstream oncogenic pathways and a crucial role for repression of insulin-like growth factor binding protein 3.

    PubMed

    Prieur, Alexandre; Tirode, Franck; Cohen, Pinchas; Delattre, Olivier

    2004-08-01

    Ewing tumors are characterized by abnormal transcription factors resulting from the oncogenic fusion of EWS with members of the ETS family, most commonly FLI-1. RNA interference targeted to the junction between EWS and FLI-1 sequences was used to inactivate the EWS/FLI-1 fusion gene in Ewing cells and to explore the resulting phenotype and alteration of the gene expression profile. Loss of expression of EWS/FLI-1 resulted in the complete arrest of growth and was associated with a dramatic increase in the number of apoptotic cells. Gene profiling of Ewing cells in which the EWS/FLI-1 fusion gene had been inactivated identified downstream targets which could be grouped in two major functional clusters related to extracellular matrix structure or remodeling and regulation of signal transduction pathways. Among these targets, the insulin-like growth factor binding protein 3 gene (IGFBP-3), a major regulator of insulin-like growth factor 1 (IGF-1) proliferation and survival signaling, was strongly induced upon treating Ewing cells with EWS/FLI-1-specific small interfering RNAs. We show that EWS/FLI-1 can bind the IGFBP-3 promoter in vitro and in vivo and can repress its activity. Moreover, IGFBP-3 silencing can partially rescue the apoptotic phenotype caused by EWS/FLI-1 inactivation. Finally, IGFBP-3-induced Ewing cell apoptosis relies on both IGF-1-dependent and -independent pathways. These findings therefore identify the repression of IGFBP-3 as a key event in the development of Ewing's sarcoma.

  4. The RNA helicase/transcriptional co-regulator, p68 (DDX5), stimulates expression of oncogenic protein kinase, Polo-like kinase-1 (PLK1), and is associated with elevated PLK1 levels in human breast cancers

    PubMed Central

    Iyer, R Sumanth; Nicol, Samantha M; Quinlan, Philip R; Thompson, Alastair M; Meek, David W; Fuller-Pace, Frances V

    2014-01-01

    p68 (DDX5) acts both as an ATP-dependent RNA helicase and as a transcriptional co-activator of several cancer-associated transcription factors, including the p53 tumor suppressor. p68 is aberrantly expressed in a high proportion of cancers, but the oncogenic drive for, or the consequences of, these expression changes remain unclear. Here we show that elevated p68 expression in a cohort of human breast cancers is associated significantly with elevated levels of the oncogenic protein kinase, Polo-like kinase-1 (PLK1). Patients expressing detectable levels of both p68 and PLK1 have a poor prognosis, but only if they also have mutation in the TP53 gene (encoding p53), suggesting that p68 can regulate PLK1 levels in a manner that is suppressed by p53. In support of this hypothesis, we show that p68 stimulates expression from the PLK1 promoter, and that silencing of endogenous p68 expression downregulates endogenous PLK1 gene expression. In the absence of functional p53, p68 stimulates the expression of PLK1 both at basal levels and in response to the clinically relevant drug, etoposide. In keeping with a role as a transcriptional activator/co-activator, chromatin immuno-precipitation analysis shows that p68 is associated with the PLK1 promoter, irrespective of the p53 status. However, its recruitment is stimulated by etoposide in cells lacking p53, suggesting that p53 can oppose association of p68 with the PLK1 promoter. These data provide a model in which p68 and p53 interplay regulates PLK1 expression, and which describes the behavior of these molecules, and the outcome of their interaction, in human breast cancer. PMID:24626184

  5. Oncogene v-jun modulates DNA replication.

    PubMed

    Wasylyk, C; Schneikert, J; Wasylyk, B

    1990-07-01

    Cell transformation leads to alterations in both transcription and DNA replication. Activation of transcription by the expression of a number of transforming oncogenes is mediated by the transcription factor AP1 (Herrlich & Ponta, 1989; Imler & Wasylyk, 1989). AP1 is a composite transcription factor, consisting of members of the jun and fos gene-families. c-jun and c-fos are progenitors of oncogenes, suggestion that an important transcriptional event in cell transformation is altered activity of AP1, which may arise either indirectly by oncogene expression or directly by structural modification of AP1. We report here that the v-jun oncogene and its progenitor c-jun, as fusion proteins with the lex-A-repressor DNA binding domain, can activate DNA replication from the Polyoma virus (Py) origin of replication, linked to the lex-A operator. The transcription-activation region of v-jun is required for activation of replication. When excess v-jun is expressed in the cell, replication is inhibited or 'squelched'. These results suggest that one consequence of deregulated jun activity could be altered DNA replication and that there are similarities in the way v-jun activates replication and transcription.

  6. The CD24 protein inducible expression system is an ideal tool to explore the potential of CD24 as an oncogene and a target for immunotherapy in vitro and in vivo.

    PubMed

    Shapira, Shiran; Kazanov, Dina; Weisblatt, Samuel; Starr, Alex; Arber, Nadir; Kraus, Sarah

    2011-11-25

    CD24 is a cell surface, heavily glycosylated glycosylphosphatidylinositol-anchored mucin-like protein that is overexpressed in various human malignancies. To accurately analyze CD24 function and dissect its biological role in a defined genetic background, it is critical to tightly regulate its expression and be able to turn it on/off in a restricted environment and at a specific time. The tetracycline-induced expression system is most promising as it exhibits such regulation, lack of pleiotropic effects, and high and rapid induction levels. To evaluate the oncogenic and immunotherapeutic potential of CD24 by applying the Tet-On system, the human CD24 gene was cloned downstream to two tetracycline operator sequences, resulting in pCDNA4/TO-CD24, which was then transfected into tetracycline (Tet) repressor-expressing cells (293T-REx), allowing tight on/off regulation, thereby resulting in a very low background or leaky CD24 expression. Selected clones were chosen for further studies and characterized in vitro and in vivo, and several treatment modalities were examined. In addition, the role of CD24 in promoting cell proliferation and tumor growth was studied. The tetracycline-dependent system was successfully implemented. Tetracycline treatment induced CD24 expression in a dose- and time-dependent fashion, which was abrogated following treatment with anti-CD24 monoclonal antibodies (mAbs). CD24-induced expression led to an increased proliferation rate that was inhibited by mAb treatment. In vivo, significantly larger tumors were developed in tetracycline-fed mice. The CD24 Tet-On system is a good model to unravel the role and underlying CD24 pathogenesis in vivo. This valuable tool allows the successful study of novel treatment options, whose effectiveness depends on the CD24 expression level. This set of experiments supports CD24 oncogenic properties.

  7. Cadherin-11 mRNA and protein expression in ovarian tumors of different malignancy: No evidence of oncogenic or tumor-suppressive function

    PubMed Central

    VON BÜLOW, CHARLOTTE; OLIVEIRA-FERRER, LETICIA; LÖNING, THOMAS; TRILLSCH, FABIAN; MAHNER, SVEN; MILDE-LANGOSCH, KARIN

    2015-01-01

    Cadherin-11 (CDH11, OB-cadherin) is a mesenchymal cadherin found to be upregulated in various types of tumors and implicated in tumor progression and metastasis. In order to determine the role of CDH11 expression in ovarian tumors, we performed a combined reverse transcription quantitative polymerase chain reaction (RT-qPCR), western blot analysis and immunohistochemical study on a large cohort of benign, borderline and invasive ovarian tumors. The RT-qPCR and western blot analysis demonstrated that the CDH11 expression was high in benign cystadenomas and decreased with increasing malignancy. This may be explained by the different tumor-stroma ratios, since immunohistochemistry revealed strong staining of stromal cells, particularly vascular smooth muscle cells and endothelial cells, but only weak cytoplasmic or nuclear immunoreactivity of cancer cells. Within the group of invasive carcinomas, high CDH11 protein expression, as detected by western blot analysis, was found to be significantly correlated with advanced stage and nodal involvement. However, the recurrence-free and overall survival analyses did not reveal any prognostic or predictive significance. In conclusion, in contrast to other tumor types, CDH11 does not play an important role in ovarian cancer progression. PMID:26623052

  8. Oncogene amplification in the proximal part of chromosome 6 in rat endometrial adenocarcinoma as revealed by combined BAC/PAC FISH, chromosome painting, zoo-FISH, and allelotyping.

    PubMed

    Adamovic, Tatjana; Trossö, Fredrik; Roshani, Leyla; Andersson, Lars; Petersen, Greta; Rajaei, Saide; Helou, Khalil; Levan, Göran

    2005-10-01

    The inbred BDII rat is a valuable experimental model for the genetic analysis of endometrial adenocarcinoma (EAC). One common aberration detected by comparative genomic hybridization in rat EAC was gain/amplification affecting the proximal part of rat chromosome 6 (RNO6). We applied rat and mouse chromosome painting probes onto tumor cell metaphase preparations in order to detect and characterize gross RNO6 aberrations. In addition, the RNO6q11-q16 segment was analyzed by fluorescence in situ hybridization with probes representing 12 cancer-related genes in the region. The analysis revealed that seven tumors contained large RNO6-derived homogeneously staining regions (HSRs) in addition to several normal or near-normal RNO6 chromosomes. Five tumors (two of which also had HSRs) exhibited a selective increase of the RNO6q11-q16 segment, sometimes in conjunction with moderate amplification of one or a few genes. Most commonly, the amplification affected the region centered around band 6q16 and included the Mycn, Ddx1, and Rrm2 genes. A second region, centering around Slc8a1 and Xdh, also was affected by gene amplification but to a lesser extent. The aberrations in the proximal part of RNO6 were further analyzed using allelotyping of microsatellite markers in all tumors from animals that were heterozygous in the proximal RNO6 region. We could detect allelic imbalance (AI) in 12 of 20 informative tumors, 6 of which were in addition to those already analyzed by molecular cytogenetic methods as described. Our findings suggest that increase/amplification of genes in this chromosome region contribute to the development of this hormone-dependent tumor.

  9. Patterns of gene expression in the sheep heart during the perinatal period revealed by transcriptomic modeling

    PubMed Central

    Rabaglino, M. Belen; Antolic, Andrew; Wood, Charles E.; Keller-Wood, Maureen

    2015-01-01

    Septa from sheep hearts at 130 days gestation, term, and 14-day-old lambs were used to model the changes in gene expression patterns during the perinatal period using Agilent 15k ovine microarrays. We used Bioconductor for R to model five major patterns of coexpressed genes. Gene ontology and transcription factor analyses using Webgestalt modeled the biological significances and transcription factors of the gene expression patterns. Modeling indicated a decreased expression of genes associated with anatomical development and differentiation during this period, whereas those associated with increased protein synthesis and growth associated with maturation of the endoplasmic reticulum rose to term but did not further increase from the near term expression. Expression of genes associated with cell responsiveness, for example, immune responses, decreased at term but expression returned by postnatal day 14. Changes in genes related to metabolism showed differential substrate-associated patterns: those related to carbohydrate metabolism rose to term and remained stable thereafter, whereas those associated with fatty acid oxidation facility rose throughout the period. The timing of many of these maturational processes was earlier in relation to birth than in the rodent. The importance of the transcription factors, estrogen-related receptors, and v-myc avian myelocytomatosis viral oncogene homolog was also highlighted in the pattern of gene expression during development of the perinatal sheep heart. PMID:26126790

  10. Patterns of gene expression in the sheep heart during the perinatal period revealed by transcriptomic modeling.

    PubMed

    Richards, Elaine M; Rabaglino, M Belen; Antolic, Andrew; Wood, Charles E; Keller-Wood, Maureen

    2015-09-01

    Septa from sheep hearts at 130 days gestation, term, and 14-day-old lambs were used to model the changes in gene expression patterns during the perinatal period using Agilent 15k ovine microarrays. We used Bioconductor for R to model five major patterns of coexpressed genes. Gene ontology and transcription factor analyses using Webgestalt modeled the biological significances and transcription factors of the gene expression patterns. Modeling indicated a decreased expression of genes associated with anatomical development and differentiation during this period, whereas those associated with increased protein synthesis and growth associated with maturation of the endoplasmic reticulum rose to term but did not further increase from the near term expression. Expression of genes associated with cell responsiveness, for example, immune responses, decreased at term but expression returned by postnatal day 14. Changes in genes related to metabolism showed differential substrate-associated patterns: those related to carbohydrate metabolism rose to term and remained stable thereafter, whereas those associated with fatty acid oxidation facility rose throughout the period. The timing of many of these maturational processes was earlier in relation to birth than in the rodent. The importance of the transcription factors, estrogen-related receptors, and v-myc avian myelocytomatosis viral oncogene homolog was also highlighted in the pattern of gene expression during development of the perinatal sheep heart.

  11. Integrative genomics analysis of chromosome 5p gain in cervical cancer reveals target over-expressed genes, including Drosha

    PubMed Central

    Scotto, Luigi; Narayan, Gopeshwar; Nandula, Subhadra V; Subramaniyam, Shivakumar; Kaufmann, Andreas M; Wright, Jason D; Pothuri, Bhavana; Mansukhani, Mahesh; Schneider, Achim; Arias-Pulido, Hugo; Murty, Vundavalli V

    2008-01-01

    Background Copy number gains and amplifications are characteristic feature of cervical cancer (CC) genomes for which the underlying mechanisms are unclear. These changes may possess oncogenic properties by deregulating tumor-related genes. Gain of short arm of chromosome 5 (5p) is the most frequent karyotypic change in CC. Methods To examine the role of 5p gain, we performed a combination of single nucleotide polymorphism (SNP) array, fluorescence in situ hybridization (FISH), and gene expression analyses on invasive cancer and in various stages of CC progression. Results The SNP and FISH analyses revealed copy number increase (CNI) of 5p in 63% of invasive CC, which arises at later stages of precancerous lesions in CC development. We integrated chromosome 5 genomic copy number and gene expression data to identify key target over expressed genes as a consequence of 5p gain. One of the candidates identified was Drosha (RNASEN), a gene that is required in the first step of microRNA (miRNA) processing in the nucleus. Other 5p genes identified as targets of CNI play a role in DNA repair and cell cycle regulation (BASP1, TARS, PAIP1, BRD9, RAD1, SKP2, and POLS), signal transduction (OSMR), and mitochondrial oxidative phosphorylation (NNT, SDHA, and NDUFS6), suggesting that disruption of pathways involving these genes may contribute to CC progression. Conclusion Taken together, we demonstrate the power of integrating genomics data with expression data in deciphering tumor-related targets of CNI. Identification of 5p gene targets in CC denotes an important step towards biomarker development and forms a framework for testing as molecular therapeutic targets. PMID:18559093

  12. The human oncogenic viruses

    SciTech Connect

    Luderer, A.A.; Weetall, H.H

    1986-01-01

    This book contains eight selections. The titles are: Cytogenetics of the Leukemias and Lymphomas; Cytogenetics of Solid Tumors: Renal Cell Carcinoma, Malignant Melanoma, Retinoblastoma, and Wilms' Tumor; Elucidation of a Normal Function for a Human Proto-Oncogene; Detection of HSV-2 Genes and Gene Products in Cervical Neoplasia; Papillomaviruses in Anogennital Neoplasms; Human Epstein-Barr Virus and Cancer; Hepatitis B Virus and Hepatocellular Carcinoma; and Kaposi's Sarcoma: Acquired Immunodeficiency Syndrome (AIDS) and Associated Viruses.

  13. The complexity of gene expression dynamics revealed by permutation entropy

    PubMed Central

    2010-01-01

    Background High complexity is considered a hallmark of living systems. Here we investigate the complexity of temporal gene expression patterns using the concept of Permutation Entropy (PE) first introduced in dynamical systems theory. The analysis of gene expression data has so far focused primarily on the identification of differentially expressed genes, or on the elucidation of pathway and regulatory relationships. We aim to study gene expression time series data from the viewpoint of complexity. Results Applying the PE complexity metric to abiotic stress response time series data in Arabidopsis thaliana, genes involved in stress response and signaling were found to be associated with the highest complexity not only under stress, but surprisingly, also under reference, non-stress conditions. Genes with house-keeping functions exhibited lower PE complexity. Compared to reference conditions, the PE of temporal gene expression patterns generally increased upon stress exposure. High-complexity genes were found to have longer upstream intergenic regions and more cis-regulatory motifs in their promoter regions indicative of a more complex regulatory apparatus needed to orchestrate their expression, and to be associated with higher correlation network connectivity degree. Arabidopsis genes also present in other plant species were observed to exhibit decreased PE complexity compared to Arabidopsis specific genes. Conclusions We show that Permutation Entropy is a simple yet robust and powerful approach to identify temporal gene expression profiles of varying complexity that is equally applicable to other types of molecular profile data. PMID:21176199

  14. The Fanconi anemia pathway controls oncogenic response in hematopoietic stem and progenitor cells by regulating PRMT5-mediated p53 arginine methylation

    PubMed Central

    Du, Wei; Amarachintha, Surya; Erden, Ozlem; Wilson, Andrew; Pang, Qishen

    2016-01-01

    The Fanconi anemia (FA) pathway is involved in DNA damage and other cellular stress responses. We have investigated the role of the FA pathway in oncogenic stress response by employing an in vivo stress-response model expressing the Gadd45β-luciferase transgene. Using two inducible models of oncogenic activation (LSL-K-rasG12D and MycER), we show that hematopoietic stem and progenitor cells (HSPCs) from mice deficient for the FA core complex components Fanca or Fancc exhibit aberrant short-lived response to oncogenic insults. Mechanistic studies reveal that FA deficiency in HSPCs impairs oncogenic stress-induced G1 cell-cycle checkpoint, resulting from a compromised K-rasG12D-induced arginine methylation of p53 mediated by the protein arginine methyltransferase 5 (PRMT5). Furthermore, forced expression of PRMT5 in HSPCs from LSL-K-rasG12D/CreER-Fanca−/− mice prolongs oncogenic response and delays leukemia development in recipient mice. Our study defines an arginine methylation-dependent FA-p53 interplay that controls oncogenic stress response. PMID:27507053

  15. Activation of endogenous c-fos proto-oncogene expression by human T-cell leukemia virus type I-encoded p40 sup tax protein in the human T-cell line, Jurkat

    SciTech Connect

    Nagata, Kinya; Ohtani, Kiyoshi; Nakamura, Masataka; Sugamura, Kazuo )

    1989-08-01

    The authors examined the ability of the trans-acting factor p40{sup tax} of human T-cell leukemia virus type I (HTLV-I), which is thought to be a crucial molecule in T-cell transformation by HTLV-I, to activate expression of a set of endogenous cellular genes related to T-cell proliferation. For this purpose, they established a subclone (JPX-9) of Jurkat cells that was stably transfected with an expression plasmid containing the p40{sup tax} gene, whose expression is definitively dependent on heavy-metal ions. Expression of the interleukin-2 receptor {alpha} chain in JPX-9 cells was induced in response to the induction of p40{sup tax} expression, as has been demonstrated by others in transient transfection experiments with Jurkat cells. In addition, they found that significant enhancement of expression of the nuclear proto-oncogene c-fos was closely associated with expression of p40{sup tax}. Continuous enhancement in the level of c-fos mRNA was observed in the presence of p40{sup tax}. These results suggest that (i) in addition to the interleukin-2-interleukin-2 receptor system, cellular genes such as c-fos, which regulate normal T-cell growth, are also activated directly or indirectly by p40{sup tax} and (ii) p40{sup tax}-induced modulation of gene expression plays a crucial role in T-cell transformation by HTLV-I.

  16. An oncogenic MYB feedback loop drives alternate cell fates in adenoid cystic carcinoma

    PubMed Central

    Drier, Yotam; Cotton, Matthew J.; Williamson, Kaylyn E.; Gillespie, Shawn M.; Ryan, Russell J.H.; Kluk, Michael J.; Carey, Christopher D.; Rodig, Scott J.; Sholl, Lynette M; Afrogheh, Amir H.; Faquin, William C.; Queimado, Lurdes; Qi, Jun; Wick, Michael J.; El-Naggar, Adel K.; Bradner, James E.; Moskaluk, Christopher A.; Aster, Jon C.; Knoechel, Birgit; Bernstein, Bradley E.

    2016-01-01

    Translocation events are frequent in cancer and may create chimeric fusions or ‘regulatory rearrangements’ that drive oncogene overexpression. Here we identify super-enhancer translocations that drive overexpression of the oncogenic transcription factor MYB as a recurrent theme in adenoid cystic carcinoma (ACC). Whole-genome sequencing data and chromatin maps reveal distinct chromosomal rearrangements that juxtapose super-enhancers to the MYB locus. Chromosome conformation capture confirms that the translocated enhancers interact with the MYB promoter. Remarkably, MYB protein binds to the translocated enhancers, creating a positive feedback loop that sustains its expression. MYB also binds enhancers that drive different regulatory programs in alternate cell lineages in ACC, cooperating with TP63 in myoepithelial cells and a Notch program in luminal epithelial cells. Bromodomain inhibitors slow tumor growth in ACC primagraft models in vivo. Thus, our study identifies super-enhancer translocations that drive MYB expression and provides insight into downstream MYB functions in the alternate ACC lineages. PMID:26829750

  17. Myc and Ras oncogenes engage different energy metabolism programs and evoke distinct patterns of oxidative and DNA replication stress.

    PubMed

    Maya-Mendoza, Apolinar; Ostrakova, Jitka; Kosar, Martin; Hall, Arnaldur; Duskova, Pavlina; Mistrik, Martin; Merchut-Maya, Joanna Maria; Hodny, Zdenek; Bartkova, Jirina; Christensen, Claus; Bartek, Jiri

    2015-03-01

    Both Myc and Ras oncogenes impact cellular metabolism, deregulate redox homeostasis and trigger DNA replication stress (RS) that compromises genomic integrity. However, how are such oncogene-induced effects evoked and temporally related, to what extent are these kinetic parameters shared by Myc and Ras, and how are these cellular changes linked with oncogene-induced cellular senescence in different cell context(s) remain poorly understood. Here, we addressed the above-mentioned open questions by multifaceted comparative analyses of human cellular models with inducible expression of c-Myc and H-RasV12 (Ras), two commonly deregulated oncoproteins operating in a functionally connected signaling network. Our study of DNA replication parameters using the DNA fiber approach and time-course assessment of perturbations in glycolytic flux, oxygen consumption and production of reactive oxygen species (ROS) revealed the following results. First, overabundance of nuclear Myc triggered RS promptly, already after one day of Myc induction, causing slow replication fork progression and fork asymmetry, even before any metabolic changes occurred. In contrast, Ras overexpression initially induced a burst of cell proliferation and increased the speed of replication fork progression. However, after several days of induction Ras caused bioenergetic metabolic changes that correlated with slower DNA replication fork progression and the ensuing cell cycle arrest, gradually leading to senescence. Second, the observed oncogene-induced RS and metabolic alterations were cell-type/context dependent, as shown by comparative analyses of normal human BJ fibroblasts versus U2-OS sarcoma cells. Third, the energy metabolic reprogramming triggered by Ras was more robust compared to impact of Myc. Fourth, the detected oncogene-induced oxidative stress was due to ROS (superoxide) of non-mitochondrial origin and mitochondrial OXPHOS was reduced (Crabtree effect). Overall, our study provides novel

  18. Fundamental Patterns Underlying Neurotoxicity Revealed by DNA Microarray Expression Profiling

    DTIC Science & Technology

    2004-09-01

    microarray analysis of the dopaminergic cell line, SN4741 , revealed induction of stress indices following MPP* treatment (Chun et al., 2001). To...response to a wide range of cellular stresses including oxidative insult of the nigral dopaminergic cell line SN4741 with hydrogen peroxide or MPP* (Salinas

  19. Retroviral Oncogenes: A Historical Primer

    PubMed Central

    Vogt, Peter K.

    2012-01-01

    Retroviruses are the original source of oncogenes. The discovery and characterization of these genes were made possible by the introduction of quantitative cell biological and molecular techniques for the study of tumor viruses. Key features of all retroviral oncogenes were first identified in src, the oncogene of Rous sarcoma virus. These include non-involvement in viral replication, coding for a single protein, and cellular origin. The myc, ras and erbB oncogenes quickly followed src, and these together with pi3k are now recognized as critical driving forces in human cancer. PMID:22898541

  20. Expression patterns reveal niche diversification in a marine microbial assemblage

    PubMed Central

    Gifford, Scott M; Sharma, Shalabh; Booth, Melissa; Moran, Mary Ann

    2013-01-01

    Resolving the ecological niches of coexisting marine microbial taxa is challenging due to the high species richness of microbial communities and the apparent functional redundancy in bacterial genomes and metagenomes. Here, we generated over 11 million Illumina reads of protein-encoding transcripts collected from well-mixed southeastern US coastal waters to characterize gene expression patterns distinguishing the ecological roles of hundreds of microbial taxa sharing the same environment. The taxa with highest in situ growth rates (based on relative abundance of ribosomal protein transcripts) were typically not the greatest contributors to community transcription, suggesting strong top-down ecological control, and their diverse transcriptomes indicated roles as metabolic generalists. The taxa with low in situ growth rates typically had low diversity transcriptomes dominated by specialized metabolisms. By identifying protein-encoding genes with atypically high expression for their level of conservation, unique functional roles of community members emerged related to substrate use (such as complex carbohydrates, fatty acids, methanesulfonate, taurine, tartrate, ectoine), alternative energy-conservation strategies (proteorhodopsin, AAnP, V-type pyrophosphatases, sulfur oxidation, hydrogen oxidation) and mechanisms for negotiating a heterogeneous environment (flagellar motility, gliding motility, adhesion strategies). On average, the heterotrophic bacterioplankton dedicated 7% of their transcriptomes to obtaining energy by non-heterotrophic means. This deep sequencing of a coastal bacterioplankton transcriptome provides the most highly resolved view of bacterioplankton niche dimensions yet available, uncovering a spectrum of unrecognized ecological strategies. PMID:22931830

  1. Genome Wide Expression Profiling of Cancer Cell Lines Cultured in Microgravity Reveals Significant Dysregulation of Cell Cycle and MicroRNA Gene Networks

    PubMed Central

    Vidyasekar, Prasanna; Shyamsunder, Pavithra; Arun, Rajpranap; Santhakumar, Rajalakshmi; Kapadia, Nand Kishore; Kumar, Ravi; Verma, Rama Shanker

    2015-01-01

    Zero gravity causes several changes in metabolic and functional aspects of the human body and experiments in space flight have demonstrated alterations in cancer growth and progression. This study reports the genome wide expression profiling of a colorectal cancer cell line-DLD-1, and a lymphoblast leukemic cell line-MOLT-4, under simulated microgravity in an effort to understand central processes and cellular functions that are dysregulated among both cell lines. Altered cell morphology, reduced cell viability and an aberrant cell cycle profile in comparison to their static controls were observed in both cell lines under microgravity. The process of cell cycle in DLD-1 cells was markedly affected with reduced viability, reduced colony forming ability, an apoptotic population and dysregulation of cell cycle genes, oncogenes, and cancer progression and prognostic markers. DNA microarray analysis revealed 1801 (upregulated) and 2542 (downregulated) genes (>2 fold) in DLD-1 cultures under microgravity while MOLT-4 cultures differentially expressed 349 (upregulated) and 444 (downregulated) genes (>2 fold) under microgravity. The loss in cell proliferative capacity was corroborated with the downregulation of the cell cycle process as demonstrated by functional clustering of DNA microarray data using gene ontology terms. The genome wide expression profile also showed significant dysregulation of post transcriptional gene silencing machinery and multiple microRNA host genes that are potential tumor suppressors and proto-oncogenes including MIR22HG, MIR17HG and MIR21HG. The MIR22HG, a tumor-suppressor gene was one of the highest upregulated genes in the microarray data showing a 4.4 log fold upregulation under microgravity. Real time PCR validated the dysregulation in the host gene by demonstrating a 4.18 log fold upregulation of the miR-22 microRNA. Microarray data also showed dysregulation of direct targets of miR-22, SP1, CDK6 and CCNA2. PMID:26295583

  2. Oncogenes in melanoma: an update.

    PubMed

    Kunz, Manfred

    2014-01-01

    Melanoma is a highly aggressive tumour with poor prognosis in the metastatic stage. BRAF, NRAS, and KIT are three well-known oncogenes involved in melanoma pathogenesis. Targeting of mutated BRAF kinase has recently been shown to significantly improve overall survival of metastatic melanoma patients, underscoring the particular role of this oncogene in melanoma biology. However, recurrences regularly occur within several months, which supposedly involve further oncogenes. Moreover, oncogenic driver mutations have not been described for up to 30% of all melanomas. In order to obtain a more complete picture of the mutational landscape of melanoma, more recent studies used high-throughput DNA sequencing technologies. A number of new oncogene candidates such as MAPK1/2, ERBB4, GRIN2A, GRM3, RAC1, and PREX2 were identified. Their particular role in melanoma biology is currently under investigation. Evidence for the functional relevance of some of these new oncogene candidates has been provided in in vitro and in vivo experiments. However, these findings await further validation in clinical studies. This review provides an overview on well-known melanoma oncogenes and new oncogene candidates, based on recent high-throughput sequencing studies. The list of genes discussed herein is of course not complete but highlights some of the most significant of recent findings in this area. The new candidates may support more individualized treatment approaches for metastatic melanoma patients in the future.

  3. Activation of ras oncogenes preceding the onset of neoplasia

    SciTech Connect

    Kumar, R.; Barbacid, M. ); Sukumar, S. )

    1990-06-01

    The identification of ras oncogenes in human and animal cancers including precancerous lesions indicates that these genes participate in the early stages of neoplastic development. Yet, these observations do not define the timing of ras oncogene activation in the multistep process of carcinogenesis. To ascertain the timing of ras oncogene activation, an animal model system was devised that involves the induction of mammary carcinomas in rats exposed at birth to the carcinogen nitrosomethylurea. High-resolution restriction fragment length polymorphism analysis of polymerase chain reaction-amplified ras sequences revealed the presence of both H-ras and K-ras oncogenes in normal mammary glands 2 weeks after carcinogen treatment and at least 2 months before the onset of neoplasia. These ras oncogenes can remain latent within the mammary gland until exposure to estrogens, demonstrating that activation of ras oncogenes can precede the onset of neoplasia and suggesting that normal physiological proliferative processes such as estrogen-induced mammary gland development may lead to neoplasia if the targeted cells harbor latent ras oncogenes.

  4. Behaviourally driven gene expression reveals song nuclei in hummingbird brain.

    PubMed

    Jarvis, E D; Ribeiro, S; da Silva, M L; Ventura, D; Vielliard, J; Mello, C V

    2000-08-10

    Hummingbirds have developed a wealth of intriguing features, such as backwards flight, ultraviolet vision, extremely high metabolic rates, nocturnal hibernation, high brain-to-body size ratio and a remarkable species-specific diversity of vocalizations. Like humans, they have also developed the rare trait of vocal learning, this being the ability to acquire vocalizations through imitation rather than instinct. Here we show, using behaviourally driven gene expression in freely ranging tropical animals, that the forebrain of hummingbirds contains seven discrete structures that are active during singing, providing the first anatomical and functional demonstration of vocal nuclei in hummingbirds. These structures are strikingly similar to seven forebrain regions that are involved in vocal learning and production in songbirds and parrots--the only other avian orders known to be vocal learners. This similarity is surprising, as songbirds, parrots and hummingbirds are thought to have evolved vocal learning and associated brain structures independently, and it indicates that strong constraints may influence the evolution of forebrain vocal nuclei.

  5. Connexin43 null mice reveal that astrocytes express multiple connexins.

    PubMed

    Dermietzel, R; Gao, Y; Scemes, E; Vieira, D; Urban, M; Kremer, M; Bennett, M V; Spray, D C

    2000-04-01

    The gap junction protein connexin43 (Cx43) is the primary component of intercellular channels in cardiac tissue and in astrocytes, the most abundant type of glial cells in the brain. Mice in which the gene for Cx43 is deleted by homologous recombination die at birth, due to profound hypertrophy of the ventricular outflow tract and stenosis of the pulmonary artery. Despite this significant cardiovascular abnormality, brains of connexin43 null [Cx43 (-/-)] animals are shown to be macroscopically normal and to display a pattern of cortical lamination that is not detectably different from wildtype siblings. Presence of Cx40 and Cx45 in brains and astrocytes cultured from both Cx43 (-/-) mice and wildtype littermates was confirmed by RT-PCR, Northern blot analyses and by immunostaining; Cx46 was detected by RT-PCR and Northern blot analyses. Presence of Cx26 in astrocyte cultures was indicated by RT-PCR and by Western blot analysis, although we were unable to resolve whether it was contributed by contaminating cells; Cx30 mRNA was detected by Northern blot in long term (2 weeks) but not fresh cultures of astrocytes. These studies thus reveal that astrocyte gap junctions may be formed of multiple connexins. Presumably, the metabolic and ionic coupling provided by these diverse gap junction types may functionally compensate for the absence of the major astrocyte gap junction protein in Cx43 (-/-) mice, providing whatever intercellular signaling is necessary for brain development and cortical lamination.

  6. Mutant calreticulin requires both its mutant C-terminus and the thrombopoietin receptor for oncogenic transformation

    PubMed Central

    Elf, Shannon; Abdelfattah, Nouran S.; Chen, Edwin; Perales-Patón, Javier; Rosen, Emily A.; Ko, Amy; Peisker, Fabian; Florescu, Natalie; Giannini, Silvia; Wolach, Ofir; Morgan, Elizabeth A.; Tothova, Zuzana; Losman, Julie-Aurore; Schneider, Rebekka K.; Al-Shahrour, Fatima; Mullally, Ann

    2016-01-01

    Somatic mutations in calreticulin (CALR) are present in approximately 40% of patients with myeloproliferative neoplasms (MPN) but the mechanism by which mutant CALR is oncogenic remains unclear. Here, we demonstrate that expression of mutant CALR alone is sufficient to engender MPN in mice and recapitulates the disease phenotype of CALR-mutant MPN patients. We further show that the thrombopoietin receptor, MPL is required for mutant CALR-driven transformation through JAK-STAT pathway activation, thus rendering mutant CALR-transformed hematopoietic cells sensitive to JAK2 inhibition. Finally, we demonstrate that the oncogenicity of mutant CALR is dependent on the positive electrostatic charge of the C-terminus of the mutant protein, which is necessary for physical interaction between mutant CALR and MPL. Together, our findings elucidate a novel paradigm of cancer pathogenesis and reveal how CALR mutations induce MPN. PMID:26951227

  7. Oncogenic K-ras expression is associated with derangement of the cAMP/PKA pathway and forskolin-reversible alterations of mitochondrial dynamics and respiration.

    PubMed

    Palorini, R; De Rasmo, D; Gaviraghi, M; Sala Danna, L; Signorile, A; Cirulli, C; Chiaradonna, F; Alberghina, L; Papa, S

    2013-01-17

    The Warburg effect in cancer cells has been proposed to involve several mechanisms, including adaptation to hypoxia, oncogenes activation or loss of oncosuppressors and impaired mitochondrial function. In previous papers, it has been shown that K-ras transformed mouse cells are much more sensitive as compared with normal cells to glucose withdrawal (undergoing apoptosis) and present a high glycolytic rate and a strong reduction of mitochondrial complex I. Recent observations suggest that transformed cells have a derangement in the cyclic adenosine monophosphate/cAMP-dependent protein kinase (cAMP/PKA) pathway, which is known to regulate several mitochondrial functions. Herein, the derangement of the cAMP/PKA pathway and its impact on transformation-linked changes of mitochondrial functions is investigated. Exogenous stimulation of PKA activity, achieved by forskolin treatment, protected K-ras-transformed cells from apoptosis induced by glucose deprivation, enhanced complex I activity, intracellular adenosine triphosphate (ATP) levels, mitochondrial fusion and decreased intracellular reactive oxygen species (ROS) levels. Several of these effects were almost completely prevented by inhibiting the PKA activity. Short-time treatment with compounds favoring mitochondrial fusion strongly decreased the cellular ROS levels especially in transformed cells. These findings support the notion that glucose shortage-induced apoptosis, specific of K-ras-transformed cells, is associated to a derangement of PKA signaling that leads to mitochondrial complex I decrease, reduction of ATP formation, prevalence of mitochondrial fission over fusion, and thereby opening new approaches for development of anticancer drugs.

  8. Structure, chromosome location, and expression of the mouse zinc finger gene Krox-20: multiple gene products and coregulation with the proto-oncogene c-fos.

    PubMed Central

    Chavrier, P; Janssen-Timmen, U; Mattéi, M G; Zerial, M; Bravo, R; Charnay, P

    1989-01-01

    We have analyzed the structure and the regulation of Krox-20, a mouse zinc finger-encoding gene which is transiently activated following serum stimulation of quiescent fibroblast cells in culture. The gene is localized on chromosome 10, band B5, in the mouse, and the homologous human gene also maps to chromosome 10 (region q21.1 to q22.1). Alternative splicing of the 5'-most intron of the Krox-20 gene gives rise to mRNAs encoding putative zinc finger proteins with different N termini. The first exon contains a sequence element with strong similarity to the c-fos proto-oncogene serum response element (SRE). This element can functionally substitute for the c-fos SRE, and it binds the same nuclear protein. It is probably responsible for the serum induction of Krox-20, possibly in combination with a weaker SRE located in the 5'-flanking region of the gene. Our findings suggest that c-fos, Krox-20, and a number of immediate-early serum response genes are coregulated and that the SRE and its cognate protein are essential components of this regulatory pathway. Images PMID:2496302

  9. Noxa upregulation by oncogenic activation of MEK/ERK through CREB promotes autophagy in human melanoma cells

    PubMed Central

    Wilmott, James S.; Yan, Xu Guang; Liu, Xiao Ying; Luan, Qi; Guo, Su Tang; Jiang, Chen Chen; Tseng, Hsin-Yi; Scolyer, Richard A.; Jin, Lei; Zhang, Xu Dong

    2014-01-01

    Reduction in the expression of the anti-survival BH3-only proteins PUMA and Bim is associated with the pathogenesis of melanoma. However, we have found that the expression of the other BH3-only protein Noxa is commonly upregulated in melanoma cells, and that this is driven by oncogenic activation of MEK/ERK. Immunohistochemistry studies showed that Noxa was expressed at higher levels in melanomas than nevi. Moreover, the expression of Noxa was increased in metastatic compared to primary melanomas, and in thick primaries compared to thin primaries. Inhibition of oncogenic BRAFV600E or MEK downregulated Noxa, whereas activation of MEK/ERK caused its upregulation. In addition, introduction of BRAFV600E increased Noxa expression in melanocytes. Upregulation of Noxa was due to a transcriptional increase mediated by cAMP responsive element binding protein, activation of which was also increased by MEK/ERK signaling in melanoma cells. Significantly, Noxa appeared necessary for constitutive activation of autophagy, albeit at low levels, by MEK/ERK in melanoma cells. Furthermore, it was required for autophagy activation that delayed apoptosis in melanoma cells undergoing nutrient deprivation. These results reveal that oncogenic activation of MEK/ERK drives Noxa expression to promote autophagy, and suggest that Noxa has an indirect anti-apoptosis role in melanoma cells under nutrient starvation conditions. PMID:25365078

  10. A RAS oncogene imparts growth factor independence to myeloid cells that abnormally regulate protein kinase C: a nonautocrine transformation pathway.

    PubMed

    Boswell, H S; Nahreini, T S; Burgess, G S; Srivastava, A; Gabig, T G; Inhorn, L; Srour, E F; Harrington, M A

    1990-06-01

    The factor-dependent cell line FDC-P1 has been utilized as a model of interleukin 3 (IL-3)-dependent myeloid cell proliferation. However, it has been recently observed that active phorbol esters (e.g., phorbol 12-myristate 13-acetate) may entirely replace IL-3 to promote its proliferation. These observations reveal abnormal regulation of protein kinase C (pkC) (absence of downregulation or overexpression). This property allowed a test of the hypothesis that the T24 RAS (codon 12) oncogene acts by constitutive and persistent pkC activation, driving proliferation. FDC-P1 cells were transfected by electroporation with the T24 RAS-containing vector pAL 8, or with a control vector pSVX Zip Neo, and neomycin-resistant clones were selected. Multiple RAS-transfectant clones were categorized for their growth factor requirement and incorporation of the 6.6-kb human mutant H-RAS genome. IL-3-independent clones had incorporated multiple (more than two) copies of the entire 6.6-kb RAS genome. The incorporation of multiple 6.6-kb RAS genomes was correlated with high-level p21 RAS expression. No evidence for autostimulatory growth factor production by clones containing the RAS oncogene was observed. Thus, acquisition of growth factor independence in myeloid cells by abundant expression of a RAS oncogene is linked, in part, to abnormal regulation of pkC, which acts as a collaborating oncogene.

  11. The Curcumin Analogue 1,5-Bis(2-hydroxyphenyl)-1,4-pentadiene-3-one Induces Apoptosis and Downregulates E6 and E7 Oncogene Expression in HPV16 and HPV18-Infected Cervical Cancer Cells.

    PubMed

    Paulraj, Felicia; Abas, Faridah; Lajis, Nordin H; Othman, Iekhsan; Hassan, Sharifah Syed; Naidu, Rakesh

    2015-06-29

    In an effort to study curcumin analogues as an alternative to improve the therapeutic efficacy of curcumin, we screened the cytotoxic potential of four diarylpentanoids using the HeLa and CaSki cervical cancer cell lines. Determination of their EC50 values indicated relatively higher potency of 1,5-bis(2-hydroxyphenyl)-1,4-pentadiene-3-one (MS17, 1.03 ± 0.5 μM; 2.6 ± 0.9 μM) and 1,5-bis(4-hydroxy-3-methoxyphenyl)-1,4-pentadiene-3-one (MS13, 2.8 ± 0.4; 6.7 ± 2.4 μM) in CaSki and HeLa, respectively, with significantly greater growth inhibition at 48 and 72 h of treatment compared to the other analogues or curcumin. Based on cytotoxic and anti-proliferative activity, MS17 was selected for comprehensive apoptotic studies. At 24 h of treatment, fluorescence microscopy detected that MS17-exposed cells exhibited significant morphological changes consistent with apoptosis, corroborated by an increase in nucleosomal enrichment due to DNA fragmentation in HeLa and CaSki cells and activation of caspase-3 activity in CaSki cells. Quantitative real-time PCR also detected significant down-regulation of HPV18- and HPV16-associated E6 and E7 oncogene expression following treatment. The overall data suggests that MS17 treatment has cytotoxic, anti-proliferative and apoptosis-inducing potential in HPV-positive cervical cancer cells. Furthermore, its role in down-regulation of HPV-associated oncogenes responsible for cancer progression merits further investigation into its chemotherapeutic role for cervical cancer.

  12. Ewing Sarcoma, an enigmatic malignancy of likely progenitor cell origin, driven by transcription factor oncogenic fusions

    PubMed Central

    Jedlicka, Paul

    2010-01-01

    Since its first description by James Ewing in 1921, Ewing Sarcoma has been a cryptic malignancy. A poorly differentiated tumor of uncertain histogenesis and aggressive biologic behavior, it is the second most common malignancy of bone and soft tissue affecting adolescents and young adults. Some two decades ago, the understanding of Ewing Sarcoma biology took a leap forward with the identification of recurrent EWS/Ets fusions, which drive onco-genesis in this disease. A further leap forward occurred over the last half decade with the application of gene silencing, global expression profiling and primary cell culture technologies to the study of this disease. Resulting work has revealed EWS/Ets fusions to be surprisingly versatile regulators of gene expression, and has narrowed the search for the elusive cell of origin. Improved understanding of EWS/Ets biology and relevant oncogenic pathways has in turn led to the development of targeted therapies, including, recently, small molecules targeting key complexes involving the oncogenic fusion itself. In many respects still remaining an enigma, Ewing Sarcoma is an important model for cancers originating in progenitor-type cells or manifesting progenitor-type cell features, and cancers containing recurrent oncogenic fusions, the latter a surprisingly expanding number. PMID:20490326

  13. Pro-oncogenic and anti-oncogenic pathways: opportunities and challenges of cancer therapy

    PubMed Central

    Zhang, Jiao; Chen, Yan-Hua; Lu, Qun

    2010-01-01

    Carcinogenesis is the uncontrolled growth of cells gaining the potential to invade and disrupt vital tissue functions. This malignant process includes the occurrence of ‘unwanted’ gene mutations that induce the transformation of normal cells, for example, by overactivation of pro-oncogenic pathways and inactivation of tumor-suppressive or anti-oncogenic pathways. It is now recognized that the number of major signaling pathways that control oncogenesis is not unlimited; therefore, suppressing these pathways can conceivably lead to a cancer cure. However, the clinical application of cancer intervention has not matched up to scientific expectations. Increasing numbers of studies have revealed that many oncogenic-signaling elements show double faces, in which they can promote or suppress cancer pathogenesis depending on tissue type, cancer stage, gene dosage and their interaction with other players in carcinogenesis. This complexity of oncogenic signaling poses challenges to traditional cancer therapy and calls for considerable caution when designing an anticancer drug strategy. We propose future oncology interventions with the concept of integrative cancer therapy. PMID:20373871

  14. An Interaction with Ewing's Sarcoma Breakpoint Protein EWS Defines a Specific Oncogenic Mechanism of ETS Factors Rearranged in Prostate Cancer.

    PubMed

    Kedage, Vivekananda; Selvaraj, Nagarathinam; Nicholas, Taylor R; Budka, Justin A; Plotnik, Joshua P; Jerde, Travis J; Hollenhorst, Peter C

    2016-10-25

    More than 50% of prostate tumors have a chromosomal rearrangement resulting in aberrant expression of an oncogenic ETS family transcription factor. However, mechanisms that differentiate the function of oncogenic ETS factors expressed in prostate tumors from non-oncogenic ETS factors expressed in normal prostate are unknown. Here, we find that four oncogenic ETS (ERG, ETV1, ETV4, and ETV5), and no other ETS, interact with the Ewing's sarcoma breakpoint protein, EWS. This EWS interaction was necessary and sufficient for oncogenic ETS functions including gene activation, cell migration, clonogenic survival, and transformation. Significantly, the EWS interacting region of ERG has no homology with that of ETV1, ETV4, and ETV5. Therefore, this finding may explain how divergent ETS factors have a common oncogenic function. Strikingly, EWS is fused to various ETS factors by the chromosome translocations that cause Ewing's sarcoma. Therefore, these findings link oncogenic ETS function in both prostate cancer and Ewing's sarcoma.

  15. Gene expression and epigenetic discovery screen reveal methylation of SFRP2 in prostate cancer.

    PubMed

    Perry, Antoinette S; O'Hurley, Gillian; Raheem, Omer A; Brennan, Kevin; Wong, Simon; O'Grady, Anthony; Kennedy, Anne-Marie; Marignol, Laure; Murphy, Therese M; Sullivan, Linda; Barrett, Ciara; Loftus, Barbara; Thornhill, John; Hewitt, Stephen M; Lawler, Mark; Kay, Elaine; Lynch, Thomas; Hollywood, Donal

    2013-04-15

    Aberrant activation of Wnts is common in human cancers, including prostate. Hypermethylation associated transcriptional silencing of Wnt antagonist genes SFRPs (Secreted Frizzled-Related Proteins) is a frequent oncogenic event. The significance of this is not known in prostate cancer. The objectives of our study were to (i) profile Wnt signaling related gene expression and (ii) investigate methylation of Wnt antagonist genes in prostate cancer. Using TaqMan Low Density Arrays, we identified 15 Wnt signaling related genes with significantly altered expression in prostate cancer; the majority of which were upregulated in tumors. Notably, histologically benign tissue from men with prostate cancer appeared more similar to tumor (r = 0.76) than to benign prostatic hyperplasia (BPH; r = 0.57, p < 0.001). Overall, the expression profile was highly similar between tumors of high (≥ 7) and low (≤ 6) Gleason scores. Pharmacological demethylation of PC-3 cells with 5-Aza-CdR reactivated 39 genes (≥ 2-fold); 40% of which inhibit Wnt signaling. Methylation frequencies in prostate cancer were 10% (2/20) (SFRP1), 64.86% (48/74) (SFRP2), 0% (0/20) (SFRP4) and 60% (12/20) (SFRP5). SFRP2 methylation was detected at significantly lower frequencies in high-grade prostatic intraepithelial neoplasia (HGPIN; 30%, (6/20), p = 0.0096), tumor adjacent benign areas (8.82%, (7/69), p < 0.0001) and BPH (11.43% (4/35), p < 0.0001). The quantitative level of SFRP2 methylation (normalized index of methylation) was also significantly higher in tumors (116) than in the other samples (HGPIN = 7.45, HB = 0.47, and BPH = 0.12). We show that SFRP2 hypermethylation is a common event in prostate cancer. SFRP2 methylation in combination with other epigenetic markers may be a useful biomarker of prostate cancer.

  16. DNA Vaccine Encoding HPV16 Oncogenes E6 and E7 Induces Potent Cell-mediated and Humoral Immunity Which Protects in Tumor Challenge and Drives E7-expressing Skin Graft Rejection

    PubMed Central

    Chandra, Janin; Dutton, Julie L.; Li, Bo; Woo, Wai-Ping; Xu, Yan; Tolley, Lynn K.; Yong, Michelle; Wells, James W.; R. Leggatt, Graham; Finlayson, Neil

    2017-01-01

    We have previously shown that a novel DNA vaccine technology of codon optimization and the addition of ubiquitin sequences enhanced immunogenicity of a herpes simplex virus 2 polynucleotide vaccine in mice, and induced cell-mediated immunity when administered in humans at relatively low doses of naked DNA. We here show that a new polynucleotide vaccine using the same technology and encoding a fusion protein of the E6 and E7 oncogenes of high-risk human papillomavirus type 16 (HPV16) is immunogenic in mice. This vaccine induces long-lasting humoral and cell-mediated immunity and protects mice from establishment of HPV16-E7-expressing tumors. In addition, it suppresses growth of readily established tumors and shows enhanced efficacy when combined with immune checkpoint blockade targeted at PD-L1. This vaccine also facilitates rejection of HPV16-E7-expressing skin grafts that demonstrate epidermal hyperplasia with characteristics of cervical and vulvar intraepithelial neoplasia. Clinical studies evaluating the efficacy of this vaccine in patients with HPV16+ premalignancies are planned. PMID:28166181

  17. Reconstructing dynamic mental models of facial expressions in prosopagnosia reveals distinct representations for identity and expression.

    PubMed

    Richoz, Anne-Raphaëlle; Jack, Rachael E; Garrod, Oliver G B; Schyns, Philippe G; Caldara, Roberto

    2015-04-01

    The human face transmits a wealth of signals that readily provide crucial information for social interactions, such as facial identity and emotional expression. Yet, a fundamental question remains unresolved: does the face information for identity and emotional expression categorization tap into common or distinct representational systems? To address this question we tested PS, a pure case of acquired prosopagnosia with bilateral occipitotemporal lesions anatomically sparing the regions that are assumed to contribute to facial expression (de)coding (i.e., the amygdala, the insula and the posterior superior temporal sulcus--pSTS). We previously demonstrated that PS does not use information from the eye region to identify faces, but relies on the suboptimal mouth region. PS's abnormal information use for identity, coupled with her neural dissociation, provides a unique opportunity to probe the existence of a dichotomy in the face representational system. To reconstruct the mental models of the six basic facial expressions of emotion in PS and age-matched healthy observers, we used a novel reverse correlation technique tracking information use on dynamic faces. PS was comparable to controls, using all facial features to (de)code facial expressions with the exception of fear. PS's normal (de)coding of dynamic facial expressions suggests that the face system relies either on distinct representational systems for identity and expression, or dissociable cortical pathways to access them. Interestingly, PS showed a selective impairment for categorizing many static facial expressions, which could be accounted for by her lesion in the right inferior occipital gyrus. PS's advantage for dynamic facial expressions might instead relate to a functionally distinct and sufficient cortical pathway directly connecting the early visual cortex to the spared pSTS. Altogether, our data provide critical insights on the healthy and impaired face systems, question evidence of deficits

  18. Human telomerase reverse transcriptase regulates vascular endothelial growth factor expression via human papillomavirus oncogene E7 in HPV-18-positive cervical cancer cells.

    PubMed

    Li, Fang; Cui, Jinquan

    2015-07-01

    Human papillomavirus (HPV) infection induces chronic and precancerous lesions and results in invasive cervical cancer. Human telomerase as well as inflammatory and angiogenic factors such as telomerase reverse transcriptase (hTERT) or vascular endothelial growth factor (VEGF) could play a role in regulating HPV-induced cervical cancer. This study investigated underlying molecular events in HPV-induced HPV-positive cervical cancer through hTERT and VEGF in vitro. Expressions of hTERT, a rate-limiting subunit of telomerase, and VEGF mRNA and proteins were, respectively, assessed by qRT-PCR, ELISA, and TRAP-ELISA in HPV-positive tissue samples and cervical cancer cell lines. To assess hTERT and VEGF secretion, hTERT overexpression and knockdown were conducted in HPV-18-positive Hela cells by hTERT cDNA and shRNA transfection, respectively. Then, the effect of HPV E6 and E7 on VEGF expressions was assessed in HPV-negative cervical cancer cells. Data have shown that VEGF expression levels are associated with hTERT expressions and telomerase activity in HPV-positive cervical cancer tissues and cells. Knockdown of hTERT expression down-regulated VEGF expressions, whereas overexpression of hTERT up-regulated VEGF expressions in HPV-18-positive Hela cells. Furthermore, HPV E7 oncoprotein was necessary for hTERT to up-regulate VEGF expressions in HPV-negative cervical cancer cells. Data from this current study indicate that HPV oncoproteins up-regulated hTERT and telomerase activity and in turn promoted VEGF expressions, which could be a key mechanism for HPV-induced cervical cancer development and progression.

  19. Cellular senescence checkpoint function determines differential Notch1-dependent oncogenic and tumor-suppressor activities.

    PubMed

    Kagawa, S; Natsuizaka, M; Whelan, K A; Facompre, N; Naganuma, S; Ohashi, S; Kinugasa, H; Egloff, A M; Basu, D; Gimotty, P A; Klein-Szanto, A J; Bass, A J; Wong, K-K; Diehl, J A; Rustgi, A K; Nakagawa, H

    2015-04-30

    Notch activity regulates tumor biology in a context-dependent and complex manner. Notch may act as an oncogene or a tumor-suppressor gene even within the same tumor type. Recently, Notch signaling has been implicated in cellular senescence. Yet, it remains unclear as to how cellular senescence checkpoint functions may interact with Notch-mediated oncogenic and tumor-suppressor activities. Herein, we used genetically engineered human esophageal keratinocytes and esophageal squamous cell carcinoma cells to delineate the functional consequences of Notch activation and inhibition along with pharmacological intervention and RNA interference experiments. When expressed in a tetracycline-inducible manner, the ectopically expressed activated form of Notch1 (ICN1) displayed oncogene-like characteristics inducing cellular senescence corroborated by the induction of G0/G1 cell-cycle arrest, Rb dephosphorylation, flat and enlarged cell morphology and senescence-associated β-galactosidase activity. Notch-induced senescence involves canonical CSL/RBPJ-dependent transcriptional activity and the p16(INK4A)-Rb pathway. Loss of p16(INK4A) or the presence of human papilloma virus (HPV) E6/E7 oncogene products not only prevented ICN1 from inducing senescence but permitted ICN1 to facilitate anchorage-independent colony formation and xenograft tumor growth with increased cell proliferation and reduced squamous-cell differentiation. Moreover, Notch1 appears to mediate replicative senescence as well as transforming growth factor-β-induced cellular senescence in non-transformed cells and that HPV E6/E7 targets Notch1 for inactivation to prevent senescence, revealing a tumor-suppressor attribute of endogenous Notch1. In aggregate, cellular senescence checkpoint functions may influence dichotomous Notch activities in the neoplastic context.

  20. Human papillomavirus oncogenic E6 protein regulates human β-defensin 3 (hBD3) expression via the tumor suppressor protein p53

    PubMed Central

    Yue, Hong; Wang, Liming; Jin, Jessica; Ghosh, Santosh K.; Kawsar, Hameem I.; Zender, Chad; Androphy, Elliot J.; Weinberg, Aaron; McCormick, Thomas S.; Jin, Ge

    2016-01-01

    Human β-defensin-3 (hBD3) is an epithelial cell-derived innate immune regulatory molecule overexpressed in oral dysplastic lesions and fosters a tumor-promoting microenvironment. Expression of hBD3 is induced by the epidermal growth factor receptor signaling pathway. Here we describe a novel pathway through which the high-risk human papillomavirus type-16 (HPV-16) oncoprotein E6 induces hBD3 expression in mucosal keratinocytes. Ablation of E6 by siRNA induces the tumor suppressor p53 and diminishes hBD3 in HPV-16 positive CaSki cervical cancer cells and UM-SCC-104 head and neck cancer cells. Malignant cells in HPV-16-associated oropharyngeal cancer overexpress hBD3. HPV-16 E6 induces hBD3 mRNA expression, peptide production and gene promoter activity in mucosal keratinocytes. Reduction of cellular levels of p53 stimulates hBD3 expression, while activation of p53 by doxorubicin inhibits its expression in primary oral keratinocytes and CaSki cells, suggesting that p53 represses hBD3 expression. A p53 binding site in the hBD3 gene promoter has been identified by using electrophoretic mobility shift assays and chromatin immunoprecipitation (ChIP). In addition, the p63 protein isoform ΔNp63α, but not TAp63, stimulated transactivation of the hBD3 gene and was co-expressed with hBD3 in head and neck cancer specimens. Therefore, high-risk HPV E6 oncoproteins may stimulate hBD3 expression in tumor cells to facilitate tumorigenesis of HPV-associated head and neck cancer. PMID:27034006

  1. Duplicate gene expression in allopolyploid Gossypium reveals two temporally distinct phases of expression evolution

    PubMed Central

    Flagel, Lex; Udall, Joshua; Nettleton, Dan; Wendel, Jonathan

    2008-01-01

    Background Polyploidy has played a prominent role in shaping the genomic architecture of the angiosperms. Through allopolyploidization, several modern Gossypium (cotton) species contain two divergent, although largely redundant genomes. Owing to this redundancy, these genomes can play host to an array of evolutionary processes that act on duplicate genes. Results We compared homoeolog (genes duplicated by polyploidy) contributions to the transcriptome of a natural allopolyploid and a synthetic interspecific F1 hybrid, both derived from a merger between diploid species from the Gossypium A-genome and D-genome groups. Relative levels of A- and D-genome contributions to the petal transcriptome were determined for 1,383 gene pairs. This comparison permitted partitioning of homoeolog expression biases into those arising from genomic merger and those resulting from polyploidy. Within allopolyploid Gossypium, approximately 24% of the genes with biased (unequal contributions from the two homoeologous copies) expression patterns are inferred to have arisen as a consequence of genomic merger, indicating that a substantial fraction of homoeolog expression biases occur instantaneously with hybridization. The remaining 76% of biased homoeologs reflect long-term evolutionary forces, such as duplicate gene neofunctionalization and subfunctionalization. Finally, we observed a greater number of genes biased toward the paternal D-genome and that expression biases have tended to increases during allopolyploid evolution. Conclusion Our results indicate that allopolyploidization entails significant homoeolog expression modulation, both immediately as a consequence of genomic merger, and secondarily as a result of long-term evolutionary transformations in duplicate gene expression. PMID:18416842

  2. The zinc finger gene ZIC2 has features of an oncogene and its over- expression correlates strongly with the clinical course of epithelial ovarian cancer

    PubMed Central

    Marchini, Sergio; Poynor, Elizabeth; Barakat, Richard R; Clivio, Luca; Cinquini, Michela; Fruscio, Robert; Porcu, Luca; Bussani, Cecilia; D’Incalci, Maurizio; Erba, Eugenio; Romano, Michela; Cattoretti, Giorgio; Katsaros, Dionyssios; Koff, Andrew; Luzzatto, Lucio

    2015-01-01

    Purpose Epithelial ovarian tumors (EOTs) are amongst the most lethal of malignancies in women. We have previously identified ZIC2 as expressed at a higher level in samples of a malignant form (MAL) of EOT than in samples of a form with low malignant potential (LMP). We have now investigated the role of ZIC2 in driving tumor growth and its association with clinical outcomes. Experimental Design ZIC2 expression levels were analysed in two independent tumor tissue collections of LMP and MAL. In vitro experiments aimed to test the role of ZIC2 as a transforming gene. Cox models were used to correlate ZIC2 expression with clinical endpoints. Results ZIC2 expression was about 40-fold in terms of mRNA and about 17-fold in terms of protein in MAL (n = 193) versus LMP (n = 39) tumors. ZIC2 mRNA levels were high in MAL cell lines, but undetectable in LMP cell lines. Over-expression of ZIC2 was localized to the nucleus. ZIC2 over-expression increases the growth rate and foci formation of NIH 3T3 cells, and stimulates anchorage-independent colony formation; down-regulation of ZIC2 decreases the growth rate of MAL cell lines. Zinc finger domains 1 and 2 are required for transforming activity. In stage I MAL ZIC2 expression was significantly associated with overall survival in both univariate (p = 0.046), and multivariate model (p = 0.049). Conclusions ZIC2, a transcription factor related to the sonic hedgehog pathway, is a strong discriminant between MAL and LMP tumors: it may be a major determinant of outcome of EOT. PMID:22733541

  3. Changes in the phenotype of human small cell lung cancer cell lines after transfection and expression of the c-myc proto-oncogene.

    PubMed Central

    Johnson, B E; Battey, J; Linnoila, I; Becker, K L; Makuch, R W; Snider, R H; Carney, D N; Minna, J D

    1986-01-01

    Small cell lung cancer growing in cell culture possesses biologic properties that allow classification into two categories: classic and variant. Compared with classic small cell lung cancer cell lines, variant lines have altered large cell morphology, shorter doubling times, higher cloning efficiencies in soft agarose, and very low levels of L dopa decarboxylase production and bombesin-like immunoreactivity. C-myc is amplified and expressed in some small cell lung cancer cell lines and all c-myc amplified lines studied to date display the variant phenotype. To investigate if c-myc amplification and expression is responsible for the variant phenotype, a normal human c-myc gene was transfected into a cloned classic small cell lung cancer cell line not amplified for or expressing detectable c-myc messenger RNA (mRNA). Clones were isolated with one to six copies of c-myc stably integrated into DNA that expressed c-myc mRNA. In addition, one clone with an integrated neo gene but a deleted c-myc gene was isolated and in this case c-myc was not expressed. C-myc expression in transfected clones was associated with altered large cell morphology, a shorter doubling time, and increased cloning efficiency, but no difference in L dopa decarboxylase levels and bombesin-like immunoreactivity. We conclude increased c-myc expression observed here in transfected clones correlates with some of the phenotypic properties distinguishing c-myc amplified variants from unamplified classic small cell lung cancer lines. Images PMID:3016030

  4. Analysis of gelsolin expression pattern in developing chicken embryo reveals high GSN expression level in tissues of neural crest origin.

    PubMed

    Mazur, Antonina Joanna; Morosan-Puopolo, Gabriela; Makowiecka, Aleksandra; Malicka-Błaszkiewicz, Maria; Nowak, Dorota; Brand-Saberi, Beate

    2016-01-01

    Gelsolin is one of the most intensively studied actin-binding proteins. However, in the literature comprehensive studies of GSN expression during development have not been performed yet in all model organisms. In zebrafish, gelsolin is a dorsalizing factor that modulates bone morphogenetic proteins signaling pathways, whereas knockout of the gelsolin coding gene, GSN is not lethal in murine model. To study the role of gelsolin in development of higher vertebrates, it is crucial to estimate GSN expression pattern during development. Here, we examined GSN expression in the developing chicken embryo. We applied numerous methods to track GSN expression in developing embryos at mRNA and protein level. We noted a characteristic GSN expression pattern. Although GSN transcripts were present in several cell types starting from early developmental stages, a relatively high GSN expression was observed in eye, brain vesicles, midbrain, neural tube, heart tube, and splanchnic mesoderm. In older embryos, we observed a high GSN expression in the cranial ganglia and dorsal root ganglia. A detailed analysis of 10-day-old chicken embryos revealed high amounts of gelsolin especially within the head region: in the olfactory and optic systems, meninges, nerves, muscles, presumptive pituitary gland, and pericytes, but not oligodendrocytes in the brain. Obtained results suggest that GSN is expressed at high levels in some tissues of ectodermal origin including all neural crest derivatives. Additionally, we describe that silencing of GSN expression in brain vesicles leads to altered morphology of the mesencephalon. This implies gelsolin is crucial for chicken brain development.

  5. EGFR/ARF6 regulation of Hh signalling stimulates oncogenic Ras tumour overgrowth.

    PubMed

    Chabu, Chiswili; Li, Da-Ming; Xu, Tian

    2017-03-10

    Multiple signalling events interact in cancer cells. Oncogenic Ras cooperates with Egfr, which cannot be explained by the canonical signalling paradigm. In turn, Egfr cooperates with Hedgehog signalling. How oncogenic Ras elicits and integrates Egfr and Hedgehog signals to drive overgrowth remains unclear. Using a Drosophila tumour model, we show that Egfr cooperates with oncogenic Ras via Arf6, which functions as a novel regulator of Hh signalling. Oncogenic Ras induces the expression of Egfr ligands. Egfr then signals through Arf6, which regulates Hh transport to promote Hh signalling. Blocking any step of this signalling cascade inhibits Hh signalling and correspondingly suppresses the growth of both, fly and human cancer cells harbouring oncogenic Ras mutations. These findings highlight a non-canonical Egfr signalling mechanism, centered on Arf6 as a novel regulator of Hh signalling. This explains both, the puzzling requirement of Egfr in oncogenic Ras-mediated overgrowth and the cooperation between Egfr and Hedgehog.

  6. EGFR/ARF6 regulation of Hh signalling stimulates oncogenic Ras tumour overgrowth

    PubMed Central

    Chabu, Chiswili; Li, Da-Ming; Xu, Tian

    2017-01-01

    Multiple signalling events interact in cancer cells. Oncogenic Ras cooperates with Egfr, which cannot be explained by the canonical signalling paradigm. In turn, Egfr cooperates with Hedgehog signalling. How oncogenic Ras elicits and integrates Egfr and Hedgehog signals to drive overgrowth remains unclear. Using a Drosophila tumour model, we show that Egfr cooperates with oncogenic Ras via Arf6, which functions as a novel regulator of Hh signalling. Oncogenic Ras induces the expression of Egfr ligands. Egfr then signals through Arf6, which regulates Hh transport to promote Hh signalling. Blocking any step of this signalling cascade inhibits Hh signalling and correspondingly suppresses the growth of both, fly and human cancer cells harbouring oncogenic Ras mutations. These findings highlight a non-canonical Egfr signalling mechanism, centered on Arf6 as a novel regulator of Hh signalling. This explains both, the puzzling requirement of Egfr in oncogenic Ras-mediated overgrowth and the cooperation between Egfr and Hedgehog. PMID:28281543

  7. Genistein suppresses prostate cancer growth through inhibition of oncogenic microRNA-151.

    PubMed

    Chiyomaru, Takeshi; Yamamura, Soichiro; Zaman, Mohd Saif; Majid, Shahana; Deng, Guoren; Shahryari, Varahram; Saini, Sharanjot; Hirata, Hiroshi; Ueno, Koji; Chang, Inik; Tanaka, Yuichiro; Tabatabai, Z Laura; Enokida, Hideki; Nakagawa, Masayuki; Dahiya, Rajvir

    2012-01-01

    Genistein has been shown to suppress the growth of several cancers through modulation of various pathways. However, the effects of genistein on the regulation of oncogenic microRNA-151 (miR-151) have not been reported. In this study, we investigated whether genistein could alter the expression of oncogenic miR-151 and its target genes that are involved in the progression and metastasis of prostate cancer (PCa). Real-time RT-PCR showed that the expression of miR-151 was higher in PC3 and DU145 cells compared with RWPE-1 cells. Treatment of PC3 and DU145 cells with 25 µM genistein down-regulated the expression of miR-151 compared with vehicle control. Inhibition of miR-151 in PCa cells by genistein significantly inhibited cell migration and invasion. In-silico analysis showed that several genes (CASZ1, IL1RAPL1, SOX17, N4BP1 and ARHGDIA) suggested to have tumor suppressive functions were target genes of miR-151. Luciferase reporter assays indicated that miR-151 directly binds to specific sites on the 3'UTR of target genes. Quantitative real-time PCR analysis showed that the mRNA expression levels of the five target genes in PC3 and DU145 were markedly changed with miR-151 mimics and inhibitor. Kaplan-Meier curves and log-rank tests revealed that high expression levels of miR-151 had an adverse effect on survival rate. This study suggests that genistein mediated suppression of oncogenic miRNAs can be an important dietary therapeutic strategy for the treatment of PCa.

  8. Genistein Suppresses Prostate Cancer Growth through Inhibition of Oncogenic MicroRNA-151

    PubMed Central

    Chiyomaru, Takeshi; Yamamura, Soichiro; Zaman, Mohd Saif; Majid, Shahana; Deng, Guoren; Shahryari, Varahram; Saini, Sharanjot; Hirata, Hiroshi; Ueno, Koji; Chang, Inik; Tanaka, Yuichiro; Tabatabai, Z. Laura; Enokida, Hideki; Nakagawa, Masayuki; Dahiya, Rajvir

    2012-01-01

    Genistein has been shown to suppress the growth of several cancers through modulation of various pathways. However, the effects of genistein on the regulation of oncogenic microRNA-151 (miR-151) have not been reported. In this study, we investigated whether genistein could alter the expression of oncogenic miR-151 and its target genes that are involved in the progression and metastasis of prostate cancer (PCa). Real-time RT-PCR showed that the expression of miR-151 was higher in PC3 and DU145 cells compared with RWPE-1 cells. Treatment of PC3 and DU145 cells with 25 µM genistein down-regulated the expression of miR-151 compared with vehicle control. Inhibition of miR-151 in PCa cells by genistein significantly inhibited cell migration and invasion. In-silico analysis showed that several genes (CASZ1, IL1RAPL1, SOX17, N4BP1 and ARHGDIA) suggested to have tumor suppressive functions were target genes of miR-151. Luciferase reporter assays indicated that miR-151 directly binds to specific sites on the 3′UTR of target genes. Quantitative real-time PCR analysis showed that the mRNA expression levels of the five target genes in PC3 and DU145 were markedly changed with miR-151 mimics and inhibitor. Kaplan-Meier curves and log-rank tests revealed that high expression levels of miR-151 had an adverse effect on survival rate. This study suggests that genistein mediated suppression of oncogenic miRNAs can be an important dietary therapeutic strategy for the treatment of PCa. PMID:22928040

  9. A human cellular sequence implicated in trk oncogene activation is DNA damage inducible

    SciTech Connect

    Ben-Ishai, R.; Scharf, R.; Sharon, R.; Kapten, I. )

    1990-08-01

    Xeroderma pigmentosum cells, which are deficient in the repair of UV light-induced DNA damage, have been used to clone DNA-damage-inducible transcripts in human cells. The cDNA clone designated pC-5 hybridizes on RNA gel blots to a 1-kilobase transcript, which is moderately abundant in nontreated cells and whose synthesis is enhanced in human cells following UV irradiation or treatment with several other DNA-damaging agents. UV-enhanced transcription of C-5 RNA is transient and occurs at lower fluences and to a greater extent in DNA-repair-deficient than in DNA-repair-proficient cells. Southern blot analysis indicates that the C-5 gene belongs to a multigene family. A cDNA clone containing the complete coding sequence of C-5 was isolated. Sequence analysis revealed that it is homologous to a human cellular sequence encoding the amino-terminal activating sequence of the trk-2h chimeric oncogene. The presence of DNA-damage-responsive sequences at the 5' end of a chimeric oncogene could result in enhanced expression of the oncogene in response to carcinogens.

  10. PIK3CA is implicated as an oncogene in ovarian cancer

    SciTech Connect

    Shayesteh, Laleh; Lu, Yiling; Kuo, Wen-Lin; Baldocchi, Russell; Godfrey, Tony; Collins, Colin; Pinkel, Daniel; Powell, Bethan; Mills,Gordon B.; Gray, Joe W.

    1998-03-25

    Ovarian cancer is the leading cause of death from gynecological malignancy and the fourth leading cause of cancer death among American women, yet little is known about its molecular aetiology. Studies using comparative genomic hybridization (CGH) have revealed several regions of recurrent, abnormal, DNA sequence copy number that may encode genes involved in the genesis or progression of the disease. One region at 3q26 found to be increased in copy number in approximately 40 percent of ovarian and other cancers contains PIK3CA, which encodes the p110 a catalytic subunit of phosphatidylinositol 3-kinase(PI3-kinase). The association between PIK3CA copy number and PI3-kinase activity makes PIK3CA a candidate oncogene because a broad range of cancer-related functions have been associated with PI3-kinase mediated signaling. These include proliferation, glucose transport and catabolism, cell adhesion, apoptosis, RAS signaling and oncogenic transformation. In addition, downstream effectors of PI3-kinase,AKT1 and AKT2, have been found to be amplified or activated in human tumors, including ovarian cancer. We show here that PIK3CA is frequently increased in copy number in ovarian cancers, that the increased copy number is associated with increased PIK3CA transcription, p110 a protein expression and PI3-kinase activity and that treatment with the PI3-kinase inhibitor LY294002 decreases proliferation and increases apoptosis. Our observations suggest PIK3CA is an oncogene that has an important role in ovarian cancer.

  11. Oncogenes and RNA splicing of human tumor viruses.

    PubMed

    Ajiro, Masahiko; Zheng, Zhi-Ming

    2014-09-01

    Approximately 10.8% of human cancers are associated with infection by an oncogenic virus. These viruses include human papillomavirus (HPV), Epstein-Barr virus (EBV), Merkel cell polyomavirus (MCV), human T-cell leukemia virus 1 (HTLV-1), Kaposi's sarcoma-associated herpesvirus (KSHV), hepatitis C virus (HCV) and hepatitis B virus (HBV). These oncogenic viruses, with the exception of HCV, require the host RNA splicing machinery in order to exercise their oncogenic activities, a strategy that allows the viruses to efficiently export and stabilize viral RNA and to produce spliced RNA isoforms from a bicistronic or polycistronic RNA transcript for efficient protein translation. Infection with a tumor virus affects the expression of host genes, including host RNA splicing factors, which play a key role in regulating viral RNA splicing of oncogene transcripts. A current prospective focus is to explore how alternative RNA splicing and the expression of viral oncogenes take place in a cell- or tissue-specific manner in virus-induced human carcinogenesis.

  12. Ethyl acetate fraction of adlay bran ethanolic extract inhibits oncogene expression and suppresses DMH-induced preneoplastic lesions of the colon in F344 rats through an anti-inflammatory pathway.

    PubMed

    Chung, Cheng-Pei; Hsu, Hsin-Yi; Huang, Din-Wen; Hsu, Hsing-Hua; Lin, Ju-Tsui; Shih, Chun-Kuang; Chiang, Wenchang

    2010-07-14

    Adlay ( Coix lachryma-jobi L. var. ma-yuen Stapf) is a grass crop and was reported to possess anti-inflammatory activity and an antiproliferative effect in cancer cell lines. The purpose of this study was to evaluate the effects of the ethyl acetate fraction of an adlay bran ethanolic extract (ABE-Ea) on colon carcinogenesis in an animal model and investigate its mechanism. Male F344 rats received 1,2-dimethylhydrazine (DMH) and consumed different doses of ABE-Ea. The medium-dose group (17.28 mg of ABE-Ea/day) exhibited the best suppressive effect on colon carcinogenesis and prevented preneoplastic mucin-depleted foci (MDF) formation. Moreover, RAS and Ets2 oncogenes were significantly down-regulated in this group compared to the negative control group, whereas Wee1, a gene involved in the cell cycle, was up-regulated. Cyclooxygenase-2 (COX-2) protein expression was significantly suppressed in all colons receiving the ABE-Ea, indicating that ABE-Ea delayed carcinogenesis by suppressing chronic inflammation. ABE-Ea included considerable a proportion of phenolic compounds, and ferulic acid was the major phenolic acid (5206 microg/g ABE-Ea) on the basis of HPLC analysis. Results from this study suggest that ABE-Ea suppressed DMH-indued preneoplastic lesions of the colon in F344 rats and that ferulic acid may be one of the active compounds.

  13. Effect of teicoplanin on the expression of c-myc and c-fos proto-oncogenes in MCF-7 breast cancer cell line

    PubMed Central

    Ashouri, Saeideh; Khujin, Maryam Hosseindokht; Kazemi, Mohammad; Kheirollahi, Majid

    2016-01-01

    Background: Teicoplanin is a member of vancomycin-ristocetin family of glycopeptide antibiotics. It mediated wound healing by increasing neovascularization possibly through activation of MAP kinase signaling pathway. The aim of this study is an evaluation of c-myc and c-fos genes expression after treatment of cells by teicoplanin and determines whether this glycopeptide antibiotic exerts its proliferation effects by influencing the expression of these genes. Hence, this study was designed to elucidate one possible mechanism underlying teicoplanin effects on cell proliferation using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Materials and Methods: Breast cancer cell line, MCF-7, was cultured, and three different concentrations of teicoplanin were added to the plates. We measured the cell proliferation rate by MTT assay. After cell harvesting, total RNA was extracted to synthesize single-stranded cDNA. Real-time polymerase chain reaction was performed, and the data were analyzed. Results: It was observed that the level of c-fos and c-myc genes’ expressions was decreased at all three different concentrations of teicoplanin. Conclusion: it could be concluded that although teicoplanin is considered as an enhancing cell growth and proliferation, but probably its effect is not through MAP kinase signaling pathway or perhaps even has inhibitory effect on the expression of some genes such as c-myc and c-fos in this pathway. Hence, the mechanism of action of teicoplanin for increasing cell propagation, through cell signaling pathways or chromosomal abnormalities, remains unclear, and further studies should be conducted. PMID:28028512

  14. Leucine Leucine-37 Uses Formyl Peptide Receptor–Like 1 to Activate Signal Transduction Pathways, Stimulate Oncogenic Gene Expression, and Enhance the Invasiveness of Ovarian Cancer Cells

    PubMed Central

    Coffelt, Seth B.; Tomchuck, Suzanne L.; Zwezdaryk, Kevin J.; Danka, Elizabeth S.; Scandurro, Aline B.

    2009-01-01

    Emerging evidence suggests that the antimicrobial peptide, leucine leucine-37 (LL-37), could play a role in the progression of solid tumors. LL-37 is expressed as the COOH terminus of human cationic antimicrobial protein-18 (hCAP-18) in ovarian, breast, and lung cancers. Previous studies have shown that the addition of LL-37 to various cancer cell lines in vitro stimulates proliferation, migration, and invasion. Similarly, overexpression of hCAP-18/LL-37 in vivo accelerates tumor growth. However, the receptor or receptors through which these processes are mediated have not been thoroughly examined. In the present study, expression of formyl peptide receptor–like 1 (FPRL1) was confirmed on ovarian cancer cells. Proliferation assays indicated that LL-37 does not signal through a G protein–coupled receptor, such as FPRL1, to promote cancer cell growth. By contrast, FPRL1 was required for LL-37–induced invasion through Matrigel. The peptide stimulated mitogen-activated protein kinase and Janus-activated kinase/signal transducers and activators of transcription signaling cascades and led to the significant activation of several transcription factors, through both FPRL1-dependent and FPRL1-independent pathways. Likewise, expression of some LL-37–stimulated genes was attenuated by the inhibition of FPRL1. Increased expression of CXCL10, EGF, and PDGF-BB as well as other soluble factors was confirmed from conditioned medium of LL-37–treated cells. Taken together, these data suggest that LL-37 potentiates a more aggressive behavior from ovarian cancer cells through its interaction with FPRL1. PMID:19491199

  15. Leucine leucine-37 uses formyl peptide receptor-like 1 to activate signal transduction pathways, stimulate oncogenic gene expression, and enhance the invasiveness of ovarian cancer cells.

    PubMed

    Coffelt, Seth B; Tomchuck, Suzanne L; Zwezdaryk, Kevin J; Danka, Elizabeth S; Scandurro, Aline B

    2009-06-01

    Emerging evidence suggests that the antimicrobial peptide, leucine leucine-37 (LL-37), could play a role in the progression of solid tumors. LL-37 is expressed as the COOH terminus of human cationic antimicrobial protein-18 (hCAP-18) in ovarian, breast, and lung cancers. Previous studies have shown that the addition of LL-37 to various cancer cell lines in vitro stimulates proliferation, migration, and invasion. Similarly, overexpression of hCAP-18/LL-37 in vivo accelerates tumor growth. However, the receptor or receptors through which these processes are mediated have not been thoroughly examined. In the present study, expression of formyl peptide receptor-like 1 (FPRL1) was confirmed on ovarian cancer cells. Proliferation assays indicated that LL-37 does not signal through a G protein-coupled receptor, such as FPRL1, to promote cancer cell growth. By contrast, FPRL1 was required for LL-37-induced invasion through Matrigel. The peptide stimulated mitogen-activated protein kinase and Janus-activated kinase/signal transducers and activators of transcription signaling cascades and led to the significant activation of several transcription factors, through both FPRL1-dependent and FPRL1-independent pathways. Likewise, expression of some LL-37-stimulated genes was attenuated by the inhibition of FPRL1. Increased expression of CXCL10, EGF, and PDGF-BB as well as other soluble factors was confirmed from conditioned medium of LL-37-treated cells. Taken together, these data suggest that LL-37 potentiates a more aggressive behavior from ovarian cancer cells through its interaction with FPRL1.

  16. TRAIL induces apoptosis in oral squamous carcinoma cells--a crosstalk with oncogenic Ras regulated cell surface expression of death receptor 5.

    PubMed

    Chen, Jun-Jie; Mikelis, Constantinos M; Zhang, Yaqin; Gutkind, J Silvio; Zhang, Baolin

    2013-02-01

    TNF-related apoptosis inducing ligand (TRAIL) induces apoptosis through its death receptors (DRs) 4 and/or 5 expressed on the surface of target cells. The selectivity of TRAIL towards cancer cells has promoted clinical evaluation of recombinant human TRAIL (rhTRAIL) and its agonistic antibodies in treating several major human cancers including colon and non-Hodgkin's lymphoma. However, little is known about their ability in killing oral squamous cell carcinoma (OSCC) cells. In this study, we tested the apoptotic responses of a panel of seven human OSCC cell lines (HN31, HN30, HN12, HN6, HN4, Cal27, and OSCC3) to rhTRAIL and monoclonal antibodies against DR4 or DR5. We found that rhTRAIL is a potent inducer of apoptosis in most of the oral cancer cell lines tested both in vitro and in vivo. We also showed that DR5 was expressed on the surface of the tested cell lines which correlated with the cellular susceptibility to apoptosis induced by rhTRAIL and anti-DR5 antibody. By contrast, little or no DR4 was detected on the surface of OSCC3 and HN6 cells rendering cellular resistance to DR4 antibody and a reduced sensitivity to rhTRAIL. Notably, the overall TRAIL sensitivity correlated well with the levels of endogenous active Ras in the cell lines tested. Expression of a constitutively active Ras mutant (RasV12) in OSCC3 cells selectively upregulated surface expression of DR5, but not DR4, and restored TRAIL sensitivity. Our findings could have implications for the use of TRAIL receptor targeted therapies in the treatment of human OSCC tumors particularly the ones harboring constitutively active Ras mutant.

  17. Novel insights of the gastric gland organization revealed by chief cell specific expression of moesin.

    PubMed

    Zhu, Lixin; Hatakeyama, Jason; Zhang, Bing; Makdisi, Joy; Ender, Cody; Forte, John G

    2009-02-01

    ERM (ezrin, radixin, and moesin) proteins play critical roles in epithelial and endothelial cell polarity, among other functions. In gastric glands, ezrin is mainly expressed in acid-secreting parietal cells, but not in mucous neck cells or zymogenic chief cells. In looking for other ERM proteins, moesin was found lining the lumen of much of the gastric gland, but it was not expressed in parietal cells. No significant radixin expression was detected in the gastric glands. Moesin showed an increased gradient of expression from the neck to the base of the glands. In addition, the staining pattern of moesin revealed a branched morphology for the gastric lumen. This pattern of short branches extending from the glandular lumen was confirmed by using antibody against zonula occludens-1 (ZO-1) to stain tight junctions. With a mucous neck cell probe (lectin GSII, from Griffonia simplicifolia) and a chief cell marker (pepsinogen C), immunohistochemistry revealed that the mucous neck cells at the top of the glands do not express moesin, but, progressing toward the base, mucous cells showing decreased GSII staining had low or moderate level of moesin expression. The level of moesin expression continued to increase toward the base of the glands and reached a plateau in the base where chief cells and parietal cells abound. The level of pepsinogen expression also increased toward the base. Pepsinogen C was located on cytoplasmic granules and/or more generally distributed in chief cells, whereas moesin was exclusively expressed on the apical membrane. This is a clear demonstration of distinctive cellular expression of two ERM family members in the same tissue. The results provide the first evidence that moesin is involved in the cell biology of chief cells. Novel insights on gastric gland morphology revealed by the moesin and ZO-1 staining provide the basis for a model of cell maturation and migration within the gland.

  18. Internal representations reveal cultural diversity in expectations of facial expressions of emotion.

    PubMed

    Jack, Rachael E; Caldara, Roberto; Schyns, Philippe G

    2012-02-01

    Facial expressions have long been considered the "universal language of emotion." Yet consistent cultural differences in the recognition of facial expressions contradict such notions (e.g., R. E. Jack, C. Blais, C. Scheepers, P. G. Schyns, & R. Caldara, 2009). Rather, culture--as an intricate system of social concepts and beliefs--could generate different expectations (i.e., internal representations) of facial expression signals. To investigate, they used a powerful psychophysical technique (reverse correlation) to estimate the observer-specific internal representations of the 6 basic facial expressions of emotion (i.e., happy, surprise, fear, disgust, anger, and sad) in two culturally distinct groups (i.e., Western Caucasian [WC] and East Asian [EA]). Using complementary statistical image analyses, cultural specificity was directly revealed in these representations. Specifically, whereas WC internal representations predominantly featured the eyebrows and mouth, EA internal representations showed a preference for expressive information in the eye region. Closer inspection of the EA observer preference revealed a surprising feature: changes of gaze direction, shown primarily among the EA group. For the first time, it is revealed directly that culture can finely shape the internal representations of common facial expressions of emotion, challenging notions of a biologically hardwired "universal language of emotion."

  19. Can plant oncogenes inhibit programmed cell death? The rolB oncogene reduces apoptosis-like symptoms in transformed plant cells.

    PubMed

    Gorpenchenko, Tatiana Y; Aminin, Dmitry L; Vereshchagina, Yuliya V; Shkryl, Yuri N; Veremeichik, Galina N; Tchernoded, Galina K; Bulgakov, Victor P

    2012-09-01

    The rolB oncogene was previously identified as an important player in ROS metabolism in transformed plant cells. Numerous reports indicate a crucial role for animal oncogenes in apoptotic cell death. Whether plant oncogenes such as rolB can induce programmed cell death (PCD) in transformed plant cells is of particular importance. In this investigation, we used a single-cell assay based on confocal microscopy and fluorescent dyes capable of discriminating between apoptotic and necrotic cells. Our results indicate that the expression of rolB in plant cells was sufficient to decrease the proportion of apoptotic cells in steady-state conditions and diminish the rate of apoptotic cells during induced PCD. These data suggest that plant oncogenes, like animal oncogenes, may be involved in the processes mediating PCD.

  20. Metabolic rewiring by oncogenic BRAF V600E links ketogenesis pathway to BRAF-MEK1 signaling

    PubMed Central

    Elf, Shannon; Ji, Quanjiang; Zhao, Liang; Jin, Lingtao; Seo, Jae Ho; Shan, Changliang; Arbiser, Jack L.; Cohen, Cynthia; Brat, Daniel; Miziorko, Henry M.; Kim, Eunhee; Abdel-Wahab, Omar; Merghoub, Taha; Fröhling, Stefan; Scholl, Claudia; Tamayo, Pablo; Barbie, David A.; Zhou, Lu; Pollack, Brian P.; Fisher, Kevin; Kudchadkar, Ragini R.; Lawson, David H.; Sica, Gabriel; Rossi, Michael; Lonial, Sagar; Khoury, Hanna J.; Khuri, Fadlo R.; Lee, Benjamin H.; Boggon, Titus J.; He, Chuan; Kang, Sumin; Chen, Jing

    2015-01-01

    SUMMARY Many human cancers share similar metabolic alterations, including the Warburg effect. However, it remains unclear whether oncogene-specific metabolic alterations are required for tumor development. Here we demonstrate a “synthetic lethal” interaction between oncogenic BRAF V600E and a ketogenic enzyme 3-hydroxy-3-methylglutaryl-CoA lyase (HMGCL). HMGCL expression is upregulated in BRAF V600E-expressing human primary melanoma and hairy cell leukemia cells. Suppression of HMGCL specifically attenuates proliferation and tumor growth potential of human melanoma cells expressing BRAF V600E. Mechanistically, active BRAF upregulates HMGCL through an octamer transcription factor Oct-1, leading to increased intracellular levels of HMGCL product, acetoacetate, which selectively enhances binding of BRAF V600E but not BRAF wild type to MEK1 in V600E-positive cancer cells to promote activation of MEK-ERK signaling. These findings reveal a mutation-specific mechanism by which oncogenic BRAF V600E “rewires” metabolic and cell signaling networks and signals through the Oct-1-HMGCL-acetoacetate axis to selectively promote BRAF V600E-dependent tumor development. PMID:26145173

  1. Chemopreventive activity of plant flavonoid isorhamnetin in colorectal cancer is mediated by oncogenic Src and β-catenin.

    PubMed

    Saud, Shakir M; Young, Matthew R; Jones-Hall, Yava L; Ileva, Lilia; Evbuomwan, Moses O; Wise, Jennifer; Colburn, Nancy H; Kim, Young S; Bobe, Gerd

    2013-09-01

    Analysis of the Polyp Prevention Trial showed an association between an isorhamnetin-rich diet and a reduced risk of advanced adenoma recurrence; however, the mechanism behind the chemoprotective effects of isorhamnetin remains unclear. Here, we show that isorhamnetin prevents colorectal tumorigenesis of FVB/N mice treated with the chemical carcinogen azoxymethane and subsequently exposed to colonic irritant dextran sodium sulfate (DSS). Dietary isorhamnetin decreased mortality, tumor number, and tumor burden by 62%, 35%, and 59%, respectively. MRI, histopathology, and immunohistochemical analysis revealed that dietary isorhamnetin resolved the DSS-induced inflammatory response faster than the control diet. Isorhamnetin inhibited AOM/DSS-induced oncogenic c-Src activation and β-catenin nuclear translocation, while promoting the expression of C-terminal Src kinase (CSK), a negative regulator of Src family of tyrosine kinases. Similarly, in HT-29 colon cancer cells, isorhamnetin inhibited oncogenic Src activity and β-catenin nuclear translocation by inducing expression of csk, as verified by RNA interference knockdown of csk. Our observations suggest the chemoprotective effects of isorhamnetin in colon cancer are linked to its anti-inflammatory activities and its inhibition of oncogenic Src activity and consequential loss of nuclear β-catenin, activities that are dependent on CSK expression.

  2. Analysis of spatial-temporal gene expression patterns reveals dynamics and regionalization in developing mouse brain.

    PubMed

    Chou, Shen-Ju; Wang, Chindi; Sintupisut, Nardnisa; Niou, Zhen-Xian; Lin, Chih-Hsu; Li, Ker-Chau; Yeang, Chen-Hsiang

    2016-01-20

    Allen Brain Atlas (ABA) provides a valuable resource of spatial/temporal gene expressions in mammalian brains. Despite rich information extracted from this database, current analyses suffer from several limitations. First, most studies are either gene-centric or region-centric, thus are inadequate to capture the superposition of multiple spatial-temporal patterns. Second, standard tools of expression analysis such as matrix factorization can capture those patterns but do not explicitly incorporate spatial dependency. To overcome those limitations, we proposed a computational method to detect recurrent patterns in the spatial-temporal gene expression data of developing mouse brains. We demonstrated that regional distinction in brain development could be revealed by localized gene expression patterns. The patterns expressed in the forebrain, medullary and pontomedullary, and basal ganglia are enriched with genes involved in forebrain development, locomotory behavior, and dopamine metabolism respectively. In addition, the timing of global gene expression patterns reflects the general trends of molecular events in mouse brain development. Furthermore, we validated functional implications of the inferred patterns by showing genes sharing similar spatial-temporal expression patterns with Lhx2 exhibited differential expression in the embryonic forebrains of Lhx2 mutant mice. These analysis outcomes confirm the utility of recurrent expression patterns in studying brain development.

  3. Mouse Elk oncogene maps to chromosome X and a novel Elk oncogene (Elk3) maps to chromosome 10

    SciTech Connect

    Tamai, Yoshitaka; Taketo, Makoto; Nozaki, Masami

    1995-03-20

    The Elk protein is a member of the Ets family found in both vertebrates and invertebrates. Human ELK1 encoded by ELK1 binds alone or together with serum response factor to DNA and regulates gene expression in a variety of biological processes. Using a panel of interspecific backcross mice, we have mapped the Elk oncogene (Elk) and a novel type Elk oncogene (Elk3), closely related to ELK1. Elk maps to Chr X, and Elk3 maps to the proximal region of Chr 10. 18 refs., 1 fig., 1 tab.

  4. First in Vivo Batrachochytrium dendrobatidis Transcriptomes Reveal Mechanisms of Host Exploitation, Host-Specific Gene Expression, and Expressed Genotype Shifts

    PubMed Central

    Ellison, Amy R.; DiRenzo, Graziella V.; McDonald, Caitlin A.; Lips, Karen R.; Zamudio, Kelly R.

    2016-01-01

    For generalist pathogens, host species represent distinct selective environments, providing unique challenges for resource acquisition and defense from host immunity, potentially resulting in host-dependent differences in pathogen fitness. Gene expression modulation should be advantageous, responding optimally to a given host and mitigating the costs of generalism. Batrachochytrium dendrobatidis (Bd), a fungal pathogen of amphibians, shows variability in pathogenicity among isolates, and within-strain virulence changes rapidly during serial passages through artificial culture. For the first time, we characterize the transcriptomic profile of Bd in vivo, using laser-capture microdissection. Comparison of Bd transcriptomes (strain JEL423) in culture and in two hosts (Atelopus zeteki and Hylomantis lemur), reveals >2000 differentially expressed genes that likely include key Bd defense and host exploitation mechanisms. Variation in Bd transcriptomes from different amphibian hosts demonstrates shifts in pathogen resource allocation. Furthermore, expressed genotype variant frequencies of Bd populations differ between culture and amphibian skin, and among host species, revealing potential mechanisms underlying rapid changes in virulence and the possibility that amphibian community composition shapes Bd evolutionary trajectories. Our results provide new insights into how changes in gene expression and infecting population genotypes can be key to the success of a generalist fungal pathogen. PMID:27856699

  5. Comparative transcriptomics of three Poaceae species reveals patterns of gene expression evolution.

    PubMed

    Davidson, Rebecca M; Gowda, Malali; Moghe, Gaurav; Lin, Haining; Vaillancourt, Brieanne; Shiu, Shin-Han; Jiang, Ning; Robin Buell, C

    2012-08-01

    The Poaceae family, also known as the grasses, includes agronomically important cereal crops such as rice, maize, sorghum, and wheat. Previous comparative studies have shown that much of the gene content is shared among the grasses; however, functional conservation of orthologous genes has yet to be explored. To gain an understanding of the genome-wide patterns of evolution of gene expression across reproductive tissues, we employed a sequence-based approach to compare analogous transcriptomes in species representing three Poaceae subgroups including the Pooideae (Brachypodium distachyon), the Panicoideae (sorghum), and the Ehrhartoideae (rice). Our transcriptome analyses reveal that only a fraction of orthologous genes exhibit conserved expression patterns. A high proportion of conserved orthologs include genes that are upregulated in physiologically similar tissues such as leaves, anther, pistil, and embryo, while orthologs that are highly expressed in seeds show the most diverged expression patterns. More generally, we show that evolution of gene expression profiles and coding sequences in the grasses may be linked. Genes that are highly and broadly expressed tend to be conserved at the coding sequence level while genes with narrow expression patterns show accelerated rates of sequence evolution. We further show that orthologs in syntenic genomic blocks are more likely to share correlated expression patterns compared with non-syntenic orthologs. These findings are important for agricultural improvement because sequence information is transferred from model species, such as Brachypodium, rice, and sorghum to crop plants without sequenced genomes.

  6. Microarray analysis reveals altered circulating microRNA expression in mice infected with Coxsackievirus B3

    PubMed Central

    Sun, Chaoyu; Tong, Lei; Zhao, Wenran; Wang, Yan; Meng, Yuan; Lin, Lexun; Liu, Bingchen; Zhai, Yujia; Zhong, Zhaohua; Li, Xueqi

    2016-01-01

    Coxsackievirus B3 (CVB3) is a common causative agent in the development of inflammatory cardiomyopathy. However, whether the expression of peripheral blood microRNAs (miRNAs) is altered in this process is unknown. The present study investigated changes to miRNA expression in the peripheral blood of CVB3-infected mice. Utilizing miRNA microarray technology, differential miRNA expression was examined between normal and CVB3-infected mice. The present results suggest that specific miRNAs were differentially expressed in the peripheral blood of mice infected with CVB3, varying with infection duration. Using miRNA microarray analysis, a total of 96 and 89 differentially expressed miRNAs were identified in the peripheral blood of mice infected with CVB3 for 3 and 6 days, respectively. Quantitative polymerase chain reaction was used to validate differentially expressed miRNAs, revealing a consistency of these results with the miRNA microarray analysis results. The biological functions of the differentially expressed miRNAs were then predicted by bioinformatics analysis. The potential biological roles of differentially expressed miRNAs included hypertrophic cardiomyopathy, dilated cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy. These results may provide important insights into the mechanisms responsible for the progression of CVB3 infection. PMID:27698715

  7. IL-33 Facilitates Oncogene Induced Cholangiocarcinoma in Mice by an IL-6 Sensitive Mechanism

    PubMed Central

    Yamada, Daisaku; Rizvi, Sumera; Razumilava, Nataliya; Bronk, Steven F.; Davila, Jaime I.; Champion, Mia D.; Borad, Mitesh J.; Bezerra, Jorge A.; Chen, Xin; Gores, Gregory J.

    2015-01-01

    Cholangiocarcinoma (CCA) is a lethal hepatobiliary neoplasm originating from the biliary apparatus. In humans, CCA risk factors include hepatobiliary inflammation and fibrosis. The recently identified IL-1 family member, IL-33, has been shown to be a biliary mitogen which also promotes liver inflammation and fibrosis. Our aim was to generate a mouse model of CCA mimicking the human disease. Ectopic oncogene expression in the biliary tract was accomplished by the Sleeping Beauty transposon transfection system with transduction of constitutively active AKT (myr-AKT) and Yes-associated protein (YAP). Intrabiliary instillation of the transposon-transposase complex was coupled with lobar bile duct ligation in CL57BL/6 mice, followed by administration of IL-33 for three consecutive days. Tumors developed in 72% of the male mice receiving both oncogenes plus IL-33 by 10 weeks, but in only 20% of the male mice transduced with the oncogenes alone. Tumors expressed SOX9 and pancytokeratin (PanCK) [features of cholangiocarcinoma] but were negative for HepPar1 [a marker of hepatocellular carcinoma (HCC)]. RNA profiling revealed substantive overlap with human CCA specimens. Not only did IL-33 induce IL-6 expression by human cholangiocytes, but IL-33 likely facilitated tumor development in vivo by an IL-6 sensitive process, as tumor development was significantly attenuated in Il-6 -/- male animals. Furthermore, tumor formation occurred at a similar rate when IL-6 was substituted for IL-33 in this model. In conclusion, the transposase-mediated transduction of constitutively active AKT and YAP in the biliary epithelium coupled with lobar obstruction and IL-33 administration results in the development of CCA with morphological and biochemical features of the human disease. This model highlights the role of inflammatory cytokines in CCA oncogenesis. PMID:25580681

  8. A Computational Drug Repositioning Approach for Targeting Oncogenic Transcription Factors

    PubMed Central

    Gayvert, Kaitlyn; Dardenne, Etienne; Cheung, Cynthia; Boland, Mary Regina; Lorberbaum, Tal; Wanjala, Jackline; Chen, Yu; Rubin, Mark; Tatonetti, Nicholas P.; Rickman, David; Elemento, Olivier

    2016-01-01

    Summary Mutations in transcription factors (TFs) genes are frequently observed in tumors, often leading to aberrant transcriptional activity. Unfortunately, TFs are often considered undruggable due to the absence of targetable enzymatic activity. To address this problem, we developed CRAFTT, a Computational drug-Repositioning Approach For Targeting Transcription factor activity. CRAFTT combines ChIP-seq with drug-induced expression profiling to identify small molecules that can specifically perturb TF activity. Application to ENCODE ChIP-seq datasets revealed known drug-TF interactions and a global drug-protein network analysis further supported these predictions. Application of CRAFTT to ERG, a pro-invasive, frequently over-expressed oncogenic TF predicted that dexamethasone would inhibit ERG activity. Indeed, dexamethasone significantly decreased cell invasion and migration in an ERG-dependent manner. Furthermore, analysis of Electronic Medical Record data indicates a protective role for dexamethasone against prostate cancer. Altogether, our method provides a broadly applicable strategy to identify drugs that specifically modulate TF activity. PMID:27264179

  9. The bcl-2 candidate proto-oncogene product is a 24-kilodalton integral-membrane protein highly expressed in lymphoid cell lines and lymphomas carrying the t(14;18) translocation.

    PubMed Central

    Chen-Levy, Z; Nourse, J; Cleary, M L

    1989-01-01

    We have identified a 24-kilodalton protein that is the product of the human bcl-2 gene, implicated as an oncogene because of its presence at the site of t(14;18) translocation breakpoints. The Bcl-2 protein was detected by specific, highly sensitive rabbit antibodies and was shown to be present in a number of human lymphoid cell lines and tissues, as well as in mouse B cells transfected with a bcl-2 cDNA construct. Characterization of the Bcl-2 protein demonstrated that it has a lipophilic nature and is associated with membrane structures, probably by means of its hydrophobic carboxy-terminal membrane-spanning domain. In t(14;18)-carrying cell lines, the protein is predominantly localized to the perinuclear endoplasmic reticulum, with a minor fraction in the plasma membrane. These properties, together with the observations that Bcl-2 does not have a characteristic signal peptide and is not glycosylated, suggest that it is an integral-membrane protein that spans the bilayer at its C-terminal hydrophobic region but is exposed only at the cytoplasmic surface. The relative abundance of the Bcl-2 protein in various human lymphoid cell lines correlated with transcription of the bcl-2 gene. The protein was abundant in all t(14;18)-carrying cell lines and lymphomas and was also found at lower levels in pre-B-cell lines and nonmalignant lymphoid tissues that do not carry t(14;18) translocations. These results suggest that the Bcl-2 protein is functional in normal B lymphocytes and that a quantitative difference in its expression may play a role in the pathogenesis of lymphomas carrying the t(14;18) translocation. Images PMID:2651903

  10. Dynamic regulation of eve stripe 2 expression reveals transcriptional bursts in living Drosophila embryos.

    PubMed

    Bothma, Jacques P; Garcia, Hernan G; Esposito, Emilia; Schlissel, Gavin; Gregor, Thomas; Levine, Michael

    2014-07-22

    We present the use of recently developed live imaging methods to examine the dynamic regulation of even-skipped (eve) stripe 2 expression in the precellular Drosophila embryo. Nascent transcripts were visualized via MS2 RNA stem loops. The eve stripe 2 transgene exhibits a highly dynamic pattern of de novo transcription, beginning with a broad domain of expression during nuclear cycle 12 (nc12), and progressive refinement during nc13 and nc14. The mature stripe 2 pattern is surprisingly transient, constituting just ∼15 min of the ∼90-min period of expression. Nonetheless, this dynamic transcription profile faithfully predicts the limits of the mature stripe visualized by conventional in situ detection methods. Analysis of individual transcription foci reveals intermittent bursts of de novo transcription, with duration cycles of 4-10 min. We discuss a multistate model of transcription regulation and speculate on its role in the dynamic repression of the eve stripe 2 expression pattern during development.

  11. Antineoplastic Effects of siRNA against TMPRSS2-ERG Junction Oncogene in Prostate Cancer

    PubMed Central

    Urbinati, Giorgia; Ali, Hafiz Muhammad; Rousseau, Quentin; Chapuis, Hubert; Desmaële, Didier; Couvreur, Patrick; Massaad-Massade, Liliane

    2015-01-01

    TMPRSS2-ERG junction oncogene is present in more than 50% of patients with prostate cancer and its expression is frequently associated with poor prognosis. Our aim is to achieve gene knockdown by siRNA TMPRSS2-ERG and then to assess the biological consequences of this inhibition. First, we designed siRNAs against the two TMPRSS2-ERG fusion variants (III and IV), most frequently identified in patients’ biopsies. Two of the five siRNAs tested were found to efficiently inhibit mRNA of both TMPRSS2-ERG variants and to decrease ERG protein expression. Microarray analysis further confirmed ERG inhibition by both siRNAs TMPRSS2-ERG and revealed one common down-regulated gene, ADRA2A, involved in cell proliferation and migration. The siRNA against TMPRSS2-ERG fusion variant IV showed the highest anti-proliferative effects: Significantly decreased cell viability, increased cleaved caspase-3 and inhibited a cluster of anti-apoptotic proteins. To propose a concrete therapeutic approach, siRNA TMPRSS2-ERG IV was conjugated to squalene, which can self-organize as nanoparticles in water. The nanoparticles of siRNA TMPRSS2-ERG-squalene injected intravenously in SCID mice reduced growth of VCaP xenografted tumours, inhibited oncoprotein expression and partially restored differentiation (decrease in Ki67). In conclusion, this study offers a new prospect of treatment for prostate cancer based on siRNA-squalene nanoparticles targeting TMPRSS2-ERG junction oncogene. PMID:25933120

  12. Effect of cellular determination on oncogenic transformation by chemicals and oncogenes.

    PubMed Central

    Harrington, M A; Gonzales, F; Jones, P A

    1988-01-01

    Three developmentally determined myogenic cell lines derived from C3H 10T1/2 C18 (10T1/2) mouse embryo cells treated with 5-azacytidine were compared with the parental 10T1/2 line for their susceptibility to oncogenic transformation by 3-methylcholanthrene or the activated human c-Ha-ras oncogene. Neither the 10T1/2 cells nor the myogenic derivatives grew in soft agar or formed tumors in nude mice. In contrast to 10T1/2 cells, the three myogenic derivatives were not susceptible to transformation by 3-methylcholanthrene, so that cellular determination altered the response of 10T1/2 cells to chemical carcinogen. On the other hand, all cell types were transformed to a tumorigenic phenotype following transfection with the activated c-Ha-ras gene. The transfected myogenic cells expressed both the c-Ha-ras gene and the muscle determination gene MyoD1. In contrast to other reports, the presence of as many as six copies of the c-Ha-ras gene per genome did not prevent the formation of striated muscle cells which expressed immunologically detectable muscle-specific myosin. The expression of the c-Ha-ras gene does not therefore necessarily preclude the expression of the determination gene for myogenesis or prevent end-stage myogenic differentiation. Images PMID:2460742

  13. Expression of the nuclear factor-kappaB and proto-oncogenes c-fos and c-jun are induced by low extracellular Mg2+ in aortic and cerebral vascular smooth muscle cells: possible links to hypertension, atherogenesis, and stroke.

    PubMed

    Altura, Burton M; Kostellow, Adele B; Zhang, Aimin; Li, Wenyan; Morrill, Gene A; Gupta, Raj K; Altura, Bella T

    2003-09-01

    Proto-oncogene (c-fos, c-jun) and nuclear factor-kappa B (NF-kappaB) expression, as well as DNA synthesis, in aortic and cerebral vascular smooth muscle cells (VSMCs) were upregulated by a decrease in extracellular magnesium ions ([Mg2+]o). Upregulation of these transcriptional factors was inversely proportional to the [Mg2+]o and occurred over the pathophysiologic range of serum Mg2+ found in patients presenting with hypertension, ischemic heart disease, and stroke. Removal of extracellular Ca2+ ([Ca2+]o), use of nifedipine or protein kinase C (PKC) inhibitors prevented the upregulation of the proto-oncogenes and DNA synthesis in VSMCs. These data show that [Mg2+]o may be an important, heretofore, overlooked natural modulator of proto-oncogene and NF-kappaB expression in VSMCs and that Ca2+ and PKC may play critical roles in induction of c-fos and c-jun in VSMCs induced by a decrease in [Mg2+]o. These results point to a role for low serum Mg2+ in potential development of hypertension, atherogenesis, vascular disease, and stroke.

  14. A new engineering approach to reveal correlation of physiological change and spontaneous expression from video images

    NASA Astrophysics Data System (ADS)

    Yang, Fenglei; Hu, Sijung; Ma, Xiaoyun; Hassan, Harnani; Wei, Dongqing

    2015-03-01

    Spontaneous expression is associated with physiological states, i.e., heart rate, respiration, oxygen saturation (SpO2%), and heart rate variability (HRV). There have yet not sufficient efforts to explore correlation of physiological change and spontaneous expression. This study aims to study how spontaneous expression is associated with physiological changes with an approved protocol or through the videos provided from Denver Intensity of Spontaneous Facial Action Database. Not like a posed expression, motion artefact in spontaneous expression is one of evitable challenges to be overcome in the study. To obtain a physiological signs from a region of interest (ROI), a new engineering approach is being developed with an artefact-reduction method consolidated 3D active appearance model (AAM) based track, affine transformation based alignment with opto-physiological mode based imaging photoplethysmography. Also, a statistical association spaces is being used to interpret correlation of spontaneous expressions and physiological states including their probability densities by means of Gaussian Mixture Model. The present work is revealing a new avenue of study associations of spontaneous expressions and physiological states with its prospect of applications on physiological and psychological assessment.

  15. Integrated Analysis of Alzheimer's Disease and Schizophrenia Dataset Revealed Different Expression Pattern in Learning and Memory.

    PubMed

    Li, Wen-Xing; Dai, Shao-Xing; Liu, Jia-Qian; Wang, Qian; Li, Gong-Hua; Huang, Jing-Fei

    2016-01-01

    Alzheimer's disease (AD) and schizophrenia (SZ) are both accompanied by impaired learning and memory functions. This study aims to explore the expression profiles of learning or memory genes between AD and SZ. We downloaded 10 AD and 10 SZ datasets from GEO-NCBI for integrated analysis. These datasets were processed using RMA algorithm and a global renormalization for all studies. Then Empirical Bayes algorithm was used to find the differentially expressed genes between patients and controls. The results showed that most of the differentially expressed genes were related to AD whereas the gene expression profile was little affected in the SZ. Furthermore, in the aspects of the number of differentially expressed genes, the fold change and the brain region, there was a great difference in the expression of learning or memory related genes between AD and SZ. In AD, the CALB1, GABRA5, and TAC1 were significantly downregulated in whole brain, frontal lobe, temporal lobe, and hippocampus. However, in SZ, only two genes CRHBP and CX3CR1 were downregulated in hippocampus, and other brain regions were not affected. The effect of these genes on learning or memory impairment has been widely studied. It was suggested that these genes may play a crucial role in AD or SZ pathogenesis. The different gene expression patterns between AD and SZ on learning and memory functions in different brain regions revealed in our study may help to understand the different mechanism between two diseases.

  16. Authentic and Play-Acted Vocal Emotion Expressions Reveal Acoustic Differences

    PubMed Central

    Jürgens, Rebecca; Hammerschmidt, Kurt; Fischer, Julia

    2011-01-01

    Play-acted emotional expressions are a frequent aspect in our life, ranging from deception to theater, film, and radio drama, to emotion research. To date, however, it remained unclear whether play-acted emotions correspond to spontaneous emotion expressions. To test whether acting influences the vocal expression of emotion, we compared radio sequences of naturally occurring emotions to actors’ portrayals. It was hypothesized that play-acted expressions were performed in a more stereotyped and aroused fashion. Our results demonstrate that speech segments extracted from play-acted and authentic expressions differ in their voice quality. Additionally, the play-acted speech tokens revealed a more variable F0-contour. Despite these differences, the results did not support the hypothesis that the variation was due to changes in arousal. This analysis revealed that differences in perception of play-acted and authentic emotional stimuli reported previously cannot simply be attributed to differences in arousal, but by slight and implicitly perceptible differences in encoding. PMID:21847385

  17. Genome wide analysis of Silurana (Xenopus) tropicalis development reveals dynamic expression using network enrichment analysis.

    PubMed

    Langlois, Valérie S; Martyniuk, Christopher J

    2013-01-01

    Development involves precise timing of gene expression and coordinated pathways for organogenesis and morphogenesis. Functional and sub-network enrichment analysis provides an integrated approach for identifying networks underlying development. The objectives of this study were to characterize early gene regulatory networks over Silurana tropicalis development from NF stage 2 to 46 using a custom Agilent 4×44K microarray. There were >8000 unique gene probes that were differentially expressed between Nieuwkoop-Faber (NF) stage 2 and stage 16, and >2000 gene probes differentially expressed between NF 34 and 46. Gene ontology revealed that genes involved in nucleosome assembly, cell division, pattern specification, neurotransmission, and general metabolism were increasingly regulated throughout development, consistent with active development. Sub-network enrichment analysis revealed that processes such as membrane hyperpolarisation, retinoic acid, cholesterol, and dopamine metabolic gene networks were activated/inhibited over time. This study identifies RNA transcripts that are potentially maternally inherited in an anuran species, provides evidence that the expression of genes involved in retinoic acid receptor signaling may increase prior to those involved in thyroid receptor signaling, and characterizes novel gene expression networks preceding organogenesis which increases understanding of the spatiotemporal embryonic development in frogs.

  18. Gene expression profiling in equine polysaccharide storage myopathy revealed inflammation, glycogenesis inhibition, hypoxia and mitochondrial dysfunctions

    PubMed Central

    Barrey, Eric; Mucher, Elodie; Jeansoule, Nicolas; Larcher, Thibaut; Guigand, Lydie; Herszberg, Bérénice; Chaffaux, Stéphane; Guérin, Gérard; Mata, Xavier; Benech, Philippe; Canale, Marielle; Alibert, Olivier; Maltere, Péguy; Gidrol, Xavier

    2009-01-01

    Background Several cases of myopathies have been observed in the horse Norman Cob breed. Muscle histology examinations revealed that some families suffer from a polysaccharide storage myopathy (PSSM). It is assumed that a gene expression signature related to PSSM should be observed at the transcriptional level because the glycogen storage disease could also be linked to other dysfunctions in gene regulation. Thus, the functional genomic approach could be conducted in order to provide new knowledge about the metabolic disorders related to PSSM. We propose exploring the PSSM muscle fiber metabolic disorders by measuring gene expression in relationship with the histological phenotype. Results Genotypying analysis of GYS1 mutation revealed 2 homozygous (AA) and 5 heterozygous (GA) PSSM horses. In the PSSM muscles, histological data revealed PAS positive amylase resistant abnormal polysaccharides, inflammation, necrosis, and lipomatosis and active regeneration of fibers. Ultrastructural evaluation revealed a decrease of mitochondrial number and structural disorders. Extensive accumulation of an abnormal polysaccharide displaced and partially replaced mitochondria and myofibrils. The severity of the disease was higher in the two homozygous PSSM horses. Gene expression analysis revealed 129 genes significantly modulated (p < 0.05). The following genes were up-regulated over 2 fold: IL18, CTSS, LUM, CD44, FN1, GST01. The most down-regulated genes were the following: mitochondrial tRNA, SLC2A2, PRKCα, VEGFα. Data mining analysis showed that protein synthesis, apoptosis, cellular movement, growth and proliferation were the main cellular functions significantly associated with the modulated genes (p < 0.05). Several up-regulated genes, especially IL18, revealed a severe muscular inflammation in PSSM muscles. The up-regulation of glycogen synthase kinase-3 (GSK3β) under its active form could be responsible for glycogen synthase (GYS1) inhibition and hypoxia-inducible factor

  19. Genome-Wide Chromosomal Targets of Oncogenic Transcription Factors

    DTIC Science & Technology

    2005-04-01

    cancer. Cancer involves, at least in part, aberrant programs of gene expression often mediated by oncogenic transcription factors activating downstream...networks that underlie complex gene expression programs that are activated in cancer. Indeed, transcription factors have been proposed as targets of...some of the limitations of ChIP-chip analysis and can be applied to transcription factors important in breast cancer such as c-myc and ER ( estrogen

  20. Gene Expression Profiling Reveals New Potential Players of Gonad Differentiation in the Chicken Embryo

    PubMed Central

    Carré, Gwenn-Aël; Couty, Isabelle; Hennequet-Antier, Christelle; Govoroun, Marina S.

    2011-01-01

    Background In birds as in mammals, a genetic switch determines whether the undifferentiated gonad develops into an ovary or a testis. However, understanding of the molecular pathway(s) involved in gonad differentiation is still incomplete. Methodology/Principal Findings With the aim of improving characterization of the molecular pathway(s) involved in gonad differentiation in the chicken embryo, we developed a large scale real time reverse transcription polymerase chain reaction approach on 110 selected genes for evaluation of their expression profiles during chicken gonad differentiation between days 5.5 and 19 of incubation. Hierarchical clustering analysis of the resulting datasets discriminated gene clusters expressed preferentially in the ovary or the testis, and/or at early or later periods of embryonic gonad development. Fitting a linear model and testing the comparisons of interest allowed the identification of new potential actors of gonad differentiation, such as Z-linked ADAMTS12, LOC427192 (corresponding to NIM1 protein) and CFC1, that are upregulated in the developing testis, and BMP3 and Z-linked ADAMTSL1, that are preferentially expressed in the developing ovary. Interestingly, the expression patterns of several members of the transforming growth factor β family were sexually dimorphic, with inhibin subunits upregulated in the testis, and bone morphogenetic protein subfamily members including BMP2, BMP3, BMP4 and BMP7, upregulated in the ovary. This study also highlighted several genes displaying asymmetric expression profiles such as GREM1 and BMP3 that are potentially involved in different aspects of gonad left-right asymmetry. Conclusion/Significance This study supports the overall conservation of vertebrate sex differentiation pathways but also reveals some particular feature of gene expression patterns during gonad development in the chicken. In particular, our study revealed new candidate genes which may be potential actors of chicken gonad

  1. Compartmentalized gene expression profiling of receptive endometrium reveals progesterone regulated ENPP3 is differentially expressed and secreted in glycosylated form

    PubMed Central

    Boggavarapu, Nageswara Rao; Lalitkumar, Sujata; Joshua, Vijay; Kasvandik, Sergo; Salumets, Andres; Lalitkumar, Parameswaran Grace; Gemzell-Danielsson, Kristina

    2016-01-01

    The complexity of endometrial receptivity at the molecular level needs to be explored in detail to improve the management of infertility. Here, differential expression of transcriptomes in receptive endometrial glands and stroma revealed Ectonucleotide Pyrophosphatase/Phosphodiesterase 3 (ENPP3) as a progesterone regulated factor and confirmed by various methods, both at mRNA and protein level. The involvement of ENPP3 in embryo attachment was tested in an in vitro model for human embryo implantation. Interestingly, there was high expression of ENPP3 mRNA in stroma but not protein. Presence of N-glycosylated ENPP3 in receptive phase uterine fluid in women confirms its regulation by progesterone and makes it possible to use in a non-invasive test of endometrial receptivity. PMID:27665743

  2. Folate levels modulate oncogene-induced replication stress and tumorigenicity

    PubMed Central

    Lamm, Noa; Maoz, Karin; Bester, Assaf C; Im, Michael M; Shewach, Donna S; Karni, Rotem; Kerem, Batsheva

    2015-01-01

    Chromosomal instability in early cancer stages is caused by replication stress. One mechanism by which oncogene expression induces replication stress is to drive cell proliferation with insufficient nucleotide levels. Cancer development is driven by alterations in both genetic and environmental factors. Here, we investigated whether replication stress can be modulated by both genetic and non-genetic factors and whether the extent of replication stress affects the probability of neoplastic transformation. To do so, we studied the effect of folate, a micronutrient that is essential for nucleotide biosynthesis, on oncogene-induced tumorigenicity. We show that folate deficiency by itself leads to replication stress in a concentration-dependent manner. Folate deficiency significantly enhances oncogene-induced replication stress, leading to increased DNA damage and tumorigenicity in vitro. Importantly, oncogene-expressing cells, when grown under folate deficiency, exhibit a significantly increased frequency of tumor development in mice. These findings suggest that replication stress is a quantitative trait affected by both genetic and non-genetic factors and that the extent of replication stress plays an important role in cancer development. PMID:26197802

  3. RNA sequencing reveals differentially expressed genes as potential diagnostic and prognostic indicators of gallbladder carcinoma

    PubMed Central

    Jiang, Mingming; Fang, Meng; Ji, Jun; Wang, Aihua; Wang, Mengmeng; Jiang, Xiaoqing; Gao, Chunfang

    2015-01-01

    Gallbladder carcinoma (GBC) is a rare tumor with a dismal survival rate overall. Hence, there is an urgent need for exploring more specific and sensitive biomarkers for the diagnosis and treatment of GBC. At first, amplified total RNAs from two paired GBC tumors and adjacent non-tumorous tissues (ANTTs) were subjected to RNA sequencing. 161 genes were identified differentially expressed between tumors and ANTTs. Functional enrichment analysis indicated that the up-regulated genes in tumor were primarily associated with signaling molecules and enzyme modulators, and mainly involved in cell cycles and pathways in cancer. Twelve differentially expressed genes (DEGs) were further confirmed in another independent cohort of 35 GBC patients. Expression levels of BIRC5, TK1, TNNT1 and MMP9 were found to be positively related to postoperative relapse. There was also a significant correlation between BIRC5 expression and tumor-node-metastasis (TNM) stage. Besides, we observed a positive correlation between serum CA19–9 concentration and the expression levels of TNNT1, MMP9 and CLIC3. Survival analysis revealed that GBC patients with high TK1 and MMP9 expression levels had worse prognosis. These identified DEGs might not only be promising biomarkers for GBC diagnosis and prognosis, but also expedite the discovery of novel therapeutic strategies. PMID:25970782

  4. Testing the Oncogenic Relevance of Cell Adhesion and Cytosketal Genes Affected by DNA Deletions in Breast Cancer

    DTIC Science & Technology

    2010-07-01

    and hair follicle derived cells as targets for the v-rasHa oncogene in mouse skin carcinogenesis. Carcinogenesis 12, 1119–1124. Wicki, A., Lehembre, F...potential oncogenic significance of genes directly involved in cell adhesion and the cytoskeleton. The aim of this study was therefore to directly test ...expression of candidate cancer genes belonging to the cytoskeletal/cell adhesion category, (2) use these tools to test the oncogenic significance of

  5. Analysis of synaptic gene expression in the neocortex of primates reveals evolutionary changes in glutamatergic neurotransmission.

    PubMed

    Muntané, Gerard; Horvath, Julie E; Hof, Patrick R; Ely, John J; Hopkins, William D; Raghanti, Mary Ann; Lewandowski, Albert H; Wray, Gregory A; Sherwood, Chet C

    2015-06-01

    Increased relative brain size characterizes the evolution of primates, suggesting that enhanced cognition plays an important part in the behavioral adaptations of this mammalian order. In addition to changes in brain anatomy, cognition can also be regulated by molecular changes that alter synaptic function, but little is known about modifications of synapses in primate brain evolution. The aim of the current study was to investigate the expression patterns and evolution of 20 synaptic genes from the prefrontal cortex of 12 primate species. The genes investigated included glutamate receptors, scaffolding proteins, synaptic vesicle components, as well as factors involved in synaptic vesicle release and structural components of the nervous system. Our analyses revealed that there have been significant changes during primate brain evolution in the components of the glutamatergic signaling pathway in terms of gene expression, protein expression, and promoter sequence changes. These results could entail functional modifications in the regulation of specific genes related to processes underlying learning and memory.

  6. Analysis of Synaptic Gene Expression in the Neocortex of Primates Reveals Evolutionary Changes in Glutamatergic Neurotransmission

    PubMed Central

    Muntané, Gerard; Horvath, Julie E.; Hof, Patrick R.; Ely, John J.; Hopkins, William D.; Raghanti, Mary Ann; Lewandowski, Albert H.; Wray, Gregory A.; Sherwood, Chet C.

    2015-01-01

    Increased relative brain size characterizes the evolution of primates, suggesting that enhanced cognition plays an important part in the behavioral adaptations of this mammalian order. In addition to changes in brain anatomy, cognition can also be regulated by molecular changes that alter synaptic function, but little is known about modifications of synapses in primate brain evolution. The aim of the current study was to investigate the expression patterns and evolution of 20 synaptic genes from the prefrontal cortex of 12 primate species. The genes investigated included glutamate receptors, scaffolding proteins, synaptic vesicle components, as well as factors involved in synaptic vesicle release and structural components of the nervous system. Our analyses revealed that there have been significant changes during primate brain evolution in the components of the glutamatergic signaling pathway in terms of gene expression, protein expression, and promoter sequence changes. These results could entail functional modifications in the regulation of specific genes related to processes underlying learning and memory. PMID:24408959

  7. What has DNA sequencing revealed about the VSG expression sites of African trypanosomes?

    PubMed

    McCulloch, Richard; Horn, David

    2009-08-01

    Antigenic variation is crucial for the survival of African trypanosomes in mammals and involves switches in expression of variant surface glycoprotein genes, which are co-transcribed with a number of expression-site-associated genes (ESAGs) from loci termed 'bloodstream expression sites' (BESs). Trypanosomes possess multiple BESs, although the reason for this (and why ESAGs are resident in these loci) has remained a subject of debate. The genome sequence of Trypanosoma brucei, released in 2005, did not include the BESs because of their telomeric disposition. This gap in our knowledge has now been bridged by two new studies, which we discuss here, asking what has been revealed about the biological significance of BES multiplicity and ESAG function and evolution.

  8. Global analysis of gene expression in pulmonary fibrosis reveals distinct programs regulating lung inflammation and fibrosis

    NASA Astrophysics Data System (ADS)

    Kaminski, Naftali; Allard, John D.; Pittet, Jean F.; Zuo, Fengrong; Griffiths, Mark J. D.; Morris, David; Huang, Xiaozhu; Sheppard, Dean; Heller, Renu A.

    2000-02-01

    The molecular mechanisms of pulmonary fibrosis are poorly understood. We have used oligonucleotide arrays to analyze the gene expression programs that underlie pulmonary fibrosis in response to bleomycin, a drug that causes lung inflammation and fibrosis, in two strains of susceptible mice (129 and C57BL/6). We then compared the gene expression patterns in these mice with 129 mice carrying a null mutation in the epithelial-restricted integrin 6 subunit (6/-), which develop inflammation but are protected from pulmonary fibrosis. Cluster analysis identified two distinct groups of genes involved in the inflammatory and fibrotic responses. Analysis of gene expression at multiple time points after bleomycin administration revealed sequential induction of subsets of genes that characterize each response. The availability of this comprehensive data set should accelerate the development of more effective strategies for intervention at the various stages in the development of fibrotic diseases of the lungs and other organs.

  9. Co-expression network analysis reveals transcription factors associated to cell wall biosynthesis in sugarcane.

    PubMed

    Ferreira, Savio Siqueira; Hotta, Carlos Takeshi; Poelking, Viviane Guzzo de Carli; Leite, Debora Chaves Coelho; Buckeridge, Marcos Silveira; Loureiro, Marcelo Ehlers; Barbosa, Marcio Henrique Pereira; Carneiro, Monalisa Sampaio; Souza, Glaucia Mendes

    2016-05-01

    Sugarcane is a hybrid of Saccharum officinarum and Saccharum spontaneum, with minor contributions from other species in Saccharum and other genera. Understanding the molecular basis of cell wall metabolism in sugarcane may allow for rational changes in fiber quality and content when designing new energy crops. This work describes a comparative expression profiling of sugarcane ancestral genotypes: S. officinarum, S. spontaneum and S. robustum and a commercial hybrid: RB867515, linking gene expression to phenotypes to identify genes for sugarcane improvement. Oligoarray experiments of leaves, immature and intermediate internodes, detected 12,621 sense and 995 antisense transcripts. Amino acid metabolism was particularly evident among pathways showing natural antisense transcripts expression. For all tissues sampled, expression analysis revealed 831, 674 and 648 differentially expressed genes in S. officinarum, S. robustum and S. spontaneum, respectively, using RB867515 as reference. Expression of sugar transporters might explain sucrose differences among genotypes, but an unexpected differential expression of histones were also identified between high and low Brix° genotypes. Lignin biosynthetic genes and bioenergetics-related genes were up-regulated in the high lignin genotype, suggesting that these genes are important for S. spontaneum to allocate carbon to lignin, while S. officinarum allocates it to sucrose storage. Co-expression network analysis identified 18 transcription factors possibly related to cell wall biosynthesis while in silico analysis detected cis-elements involved in cell wall biosynthesis in their promoters. Our results provide information to elucidate regulatory networks underlying traits of interest that will allow the improvement of sugarcane for biofuel and chemicals production.

  10. Inhibition of the Pim1 Oncogene Results in Diminished Visual Function

    PubMed Central

    Yin, Jun; Shine, Lisa; Raycroft, Francis; Deeti, Sudhakar; Reynolds, Alison; Ackerman, Kristin M.; Glaviano, Antonino; O'Farrell, Sean; O'Leary, Olivia; Kilty, Claire; Kennedy, Ciaran; McLoughlin, Sarah; Rice, Megan; Russell, Eileen; Higgins, Desmond G.; Hyde, David R.; Kennedy, Breandan N.

    2012-01-01

    Our objective was to profile genetic pathways whose differential expression correlates with maturation of visual function in zebrafish. Bioinformatic analysis of transcriptomic data revealed Jak-Stat signalling as the pathway most enriched in the eye, as visual function develops. Real-time PCR, western blotting, immunohistochemistry and in situ hybridization data confirm that multiple Jak-Stat pathway genes are up-regulated in the zebrafish eye between 3–5 days post-fertilisation, times associated with significant maturation of vision. One of the most up-regulated Jak-Stat genes is the proto-oncogene Pim1 kinase, previously associated with haematological malignancies and cancer. Loss of function experiments using Pim1 morpholinos or Pim1 inhibitors result in significant diminishment of visual behaviour and function. In summary, we have identified that enhanced expression of Jak-Stat pathway genes correlates with maturation of visual function and that the Pim1 oncogene is required for normal visual function. PMID:23300608

  11. Gene expression analysis of endometrium reveals progesterone resistance and candidate susceptibility genes in women with endometriosis.

    PubMed

    Burney, Richard O; Talbi, Said; Hamilton, Amy E; Vo, Kim Chi; Nyegaard, Mette; Nezhat, Camran R; Lessey, Bruce A; Giudice, Linda C

    2007-08-01

    The identification of molecular differences in the endometrium of women with endometriosis is an important step toward understanding the pathogenesis of this condition and toward developing novel strategies for the treatment of associated infertility and pain. In this study, we conducted global gene expression analysis of endometrium from women with and without moderate/severe stage endometriosis and compared the gene expression signatures across various phases of the menstrual cycle. The transcriptome analysis revealed molecular dysregulation of the proliferative-to-secretory transition in endometrium of women with endometriosis. Paralleled gene expression analysis of endometrial specimens obtained during the early secretory phase demonstrated a signature of enhanced cellular survival and persistent expression of genes involved in DNA synthesis and cellular mitosis in the setting of endometriosis. Comparative gene expression analysis of progesterone-regulated genes in secretory phase endometrium confirmed the observation of attenuated progesterone response. Additionally, interesting candidate susceptibility genes were identified that may be associated with this disorder, including FOXO1A, MIG6, and CYP26A1. Collectively these findings provide a framework for further investigations on causality and mechanisms underlying attenuated progesterone response in endometrium of women with endometriosis.

  12. Comparison of larval and adult Drosophila astrocytes reveals stage-specific gene expression profiles.

    PubMed

    Huang, Yanmei; Ng, Fanny S; Jackson, F Rob

    2015-02-04

    The analysis of adult astrocyte glial cells has revealed a remarkable heterogeneity with regard to morphology, molecular signature, and physiology. A key question in glial biology is how such heterogeneity arises during brain development. One approach to this question is to identify genes with differential astrocyte expression during development; certain genes expressed later in neural development may contribute to astrocyte differentiation. We have utilized the Drosophila model and Translating Ribosome Affinity Purification (TRAP)-RNA-seq methods to derive the genome-wide expression profile of Drosophila larval astrocyte-like cells (hereafter referred to as astrocytes) for the first time. These studies identified hundreds of larval astrocyte-enriched genes that encode proteins important for metabolism, energy production, and protein synthesis, consistent with the known role of astrocytes in the metabolic support of neurons. Comparison of the larval profile with that observed for adults has identified genes with astrocyte-enriched expression specific to adulthood. These include genes important for metabolism and energy production, translation, chromatin modification, protein glycosylation, neuropeptide signaling, immune responses, vesicle-mediated trafficking or secretion, and the regulation of behavior. Among these functional classes, the expression of genes important for chromatin modification and vesicle-mediated trafficking or secretion is overrepresented in adult astrocytes based on Gene Ontology analysis. Certain genes with selective adult enrichment may mediate functions specific to this stage or may be important for the differentiation or maintenance of adult astrocytes, with the latter perhaps contributing to population heterogeneity.

  13. Oncogenicity of L-type amino-acid transporter 1 (LAT1) revealed by targeted gene disruption in chicken DT40 cells: LAT1 is a promising molecular target for human cancer therapy

    SciTech Connect

    Ohkawa, Mayumi; Ohno, Yoshiya; Masuko, Kazue; Takeuchi, Akiko; Suda, Kentaro; Kubo, Akihiro; Kawahara, Rieko; Okazaki, Shogo; Tanaka, Toshiyuki; Saya, Hideyuki; Seki, Masayuki; Enomoto, Takemi; Yagi, Hideki; Hashimoto, Yoshiyuki; Masuko, Takashi

    2011-03-25

    Highlights: {yields} We established LAT1 amino-acid transporter-disrupted DT40 cells. {yields} LAT1-disrupted cells showed slow growth and lost the oncogenicity. {yields} siRNA and mAb inhibited human tumor growth in vitro and in vivo. {yields} LAT1 is a promising target molecule for cancer therapy. -- Abstract: L-type amino-acid transporter 1 (LAT1) is the first identified light chain of CD98 molecule, disulfide-linked to a heavy chain of CD98. Following cDNA cloning of chicken full-length LAT1, we have constructed targeting vectors for the disruption of chicken LAT1 gene from genomic DNA of chicken LAT1 consisting of 5.4 kb. We established five homozygous LAT1-disrupted (LAT1{sup -/-}) cell clones, derived from a heterozygous LAT1{sup +/-} clone of DT40 chicken B cell line. Reactivity of anti-chicken CD98hc monoclonal antibody (mAb) with LAT1{sup -/-} DT40 cells was markedly decreased compared with that of wild-type DT40 cells. All LAT1{sup -/-} cells were deficient in L-type amino-acid transporting activity, although alternative-splice variant but not full-length mRNA of LAT1 was detected in these cells. LAT1{sup -/-} DT40 clones showed outstandingly slow growth in liquid culture and decreased colony-formation capacity in soft agar compared with wild-type DT40 cells. Cell-cycle analyses indicated that LAT1{sup -/-} DT40 clones have prolonged cell-cycle phases compared with wild-type or LAT1{sup +/-} DT40 cells. Knockdown of human LAT1 by small interfering RNAs resulted in marked in vitro cell-growth inhibition of human cancer cells, and in vivo tumor growth of HeLa cells in athymic mice was significantly inhibited by anti-human LAT1 mAb. All these results indicate essential roles of LAT1 in the cell proliferation and occurrence of malignant phenotypes and that LAT1 is a promising candidate as a molecular target of human cancer therapy.

  14. Astrocyte heterogeneity revealed by expression of a GFAP-LacZ transgene.

    PubMed

    Lee, Youngjin; Su, Mu; Messing, Albee; Brenner, Michael

    2006-05-01

    Glial fibrillary acidic protein (GFAP) is an intermediate filament protein present primarily in astrocytes. The gene is first expressed as astrocytes mature, and in the adult is strongly upregulated in response to CNS damage. Thus, in addition to its astrocyte specificity, transcriptional regulation of the GFAP gene is of interest as a reporter of CNS signaling during development and injury. Several laboratories have shown that approximately 2 kb of 5'-flanking DNA of the human or mouse GFAP gene is sufficient to direct transgene expression to astrocytes and to confer developmental and injury-induced regulation. Enhancer regions have been identified adjacent to the basal promoter and about 1500 bp upstream of the RNA start site. Juxtaposition of these two segments yielded a 447 bp promoter, gfa28, which strongly drove reporter activity in transfected glioma cells. We report here that in mice a gfa28-lacZ transgene expresses in only certain brain regions, revealing an unexpected heterogeneity among astrocytes. The restricted pattern of expression is present early in development, is not altered by injury, and is preserved in cultured astrocytes. However, astrocytes cultured from an inactive region strongly express a transiently transfected gfa28-lacZ construct, and activity of the embedded gfa28-lacZ transgene is partially restored by treatment with a histone deacetylase inhibitor. These results indicate that the absence of gfa28-lacZ expression in specific brain regions results from a developmental failure to remodel GFAP chromatin to an open structure. Thus, expression of the gfa28-lacZ transgene appears to serendipitously mark a distinct set of astrocyte precursors.

  15. State of the art address oncogenes and tumor-suppressing genes

    SciTech Connect

    Frazier, M.E.

    1989-05-01

    Cancer has a myriad of causes but, whatever the cause, the changes that result in neoplasia are usually genetic. Although not all DNA damage results in cancer, evidence implicates two broad classes of genes in carcinogenesis. The first class, oncogenes are genes that cause cancer. An oncogene results when there is increased and/or changed expression of the proto-oncogene. Oncogenes are dominant: when activated, they predominate over the activity of any normal alleles in the cell. Thus oncogenes act directly to cause cancer. The second class of genes associated with cancer are tumor-suppressing genes, which either code directly for, or control expression of a wide spectrum of tissue-specific differentiation antigens. Malignancy occurs in a specific cell type when expression of an appropriate tumor-suppressing gene is, homozygously, seriously distorted or completely lacking. Tumor suppressing genes also appear to regulate expression of a third, uncharacterized group of cancer-related genes that act in a recessive manner and are not expressed in the presence of the tumor-suppressing genes. We will first discuss oncogenes, then the tumor-suppressing genes. Experimental data will be used to illustrate key features of the carcinogenic process.

  16. Representing high throughput expression profiles via perturbation barcodes reveals compound targets.

    PubMed

    Filzen, Tracey M; Kutchukian, Peter S; Hermes, Jeffrey D; Li, Jing; Tudor, Matthew

    2017-02-01

    High throughput mRNA expression profiling can be used to characterize the response of cell culture models to perturbations such as pharmacologic modulators and genetic perturbations. As profiling campaigns expand in scope, it is important to homogenize, summarize, and analyze the resulting data in a manner that captures significant biological signals in spite of various noise sources such as batch effects and stochastic variation. We used the L1000 platform for large-scale profiling of 978 representative genes across thousands of compound treatments. Here, a method is described that uses deep learning techniques to convert the expression changes of the landmark genes into a perturbation barcode that reveals important features of the underlying data, performing better than the raw data in revealing important biological insights. The barcode captures compound structure and target information, and predicts a compound's high throughput screening promiscuity, to a higher degree than the original data measurements, indicating that the approach uncovers underlying factors of the expression data that are otherwise entangled or masked by noise. Furthermore, we demonstrate that visualizations derived from the perturbation barcode can be used to more sensitively assign functions to unknown compounds through a guilt-by-association approach, which we use to predict and experimentally validate the activity of compounds on the MAPK pathway. The demonstrated application of deep metric learning to large-scale chemical genetics projects highlights the utility of this and related approaches to the extraction of insights and testable hypotheses from big, sometimes noisy data.

  17. Representing high throughput expression profiles via perturbation barcodes reveals compound targets

    PubMed Central

    Kutchukian, Peter S.; Li, Jing; Tudor, Matthew

    2017-01-01

    High throughput mRNA expression profiling can be used to characterize the response of cell culture models to perturbations such as pharmacologic modulators and genetic perturbations. As profiling campaigns expand in scope, it is important to homogenize, summarize, and analyze the resulting data in a manner that captures significant biological signals in spite of various noise sources such as batch effects and stochastic variation. We used the L1000 platform for large-scale profiling of 978 representative genes across thousands of compound treatments. Here, a method is described that uses deep learning techniques to convert the expression changes of the landmark genes into a perturbation barcode that reveals important features of the underlying data, performing better than the raw data in revealing important biological insights. The barcode captures compound structure and target information, and predicts a compound’s high throughput screening promiscuity, to a higher degree than the original data measurements, indicating that the approach uncovers underlying factors of the expression data that are otherwise entangled or masked by noise. Furthermore, we demonstrate that visualizations derived from the perturbation barcode can be used to more sensitively assign functions to unknown compounds through a guilt-by-association approach, which we use to predict and experimentally validate the activity of compounds on the MAPK pathway. The demonstrated application of deep metric learning to large-scale chemical genetics projects highlights the utility of this and related approaches to the extraction of insights and testable hypotheses from big, sometimes noisy data. PMID:28182661

  18. A Balanced Tissue Composition Reveals New Metabolic and Gene Expression Markers in Prostate Cancer

    PubMed Central

    Tessem, May-Britt; Bertilsson, Helena; Angelsen, Anders; Bathen, Tone F.; Drabløs, Finn; Rye, Morten Beck

    2016-01-01

    Molecular analysis of patient tissue samples is essential to characterize the in vivo variability in human cancers which are not accessible in cell-lines or animal models. This applies particularly to studies of tumor metabolism. The challenge is, however, the complex mixture of various tissue types within each sample, such as benign epithelium, stroma and cancer tissue, which can introduce systematic biases when cancers are compared to normal samples. In this study we apply a simple strategy to remove such biases using sample selections where the average content of stroma tissue is balanced between the sample groups. The strategy is applied to a prostate cancer patient cohort where data from MR spectroscopy and gene expression have been collected from and integrated on the exact same tissue samples. We reveal in vivo changes in cancer-relevant metabolic pathways which are otherwise hidden in the data due to tissue confounding. In particular, lowered levels of putrescine are connected to increased expression of SRM, reduced levels of citrate are attributed to upregulation of genes promoting fatty acid synthesis, and increased succinate levels coincide with reduced expression of SUCLA2 and SDHD. In addition, the strategy also highlights important metabolic differences between the stroma, epithelium and prostate cancer. These results show that important in vivo metabolic features of cancer can be revealed from patient data only if the heterogeneous tissue composition is properly accounted for in the analysis. PMID:27100877

  19. A combined oncogenic pathway signature of BRAF, KRAS and PI3KCA mutation improves colorectal cancer classification and cetuximab treatment prediction

    PubMed Central

    Tian, Sun; Simon, Iris; Moreno, Victor; Roepman, Paul; Tabernero, Josep; Snel, Mireille; van't Veer, Laura; Salazar, Ramon; Bernards, Rene

    2013-01-01

    Objective To develop gene expression profiles that characterise KRAS-, BRAF- or PIK3CA-activated- tumours, and to explore whether these profiles might be helpful in predicting the response to the epidermal growth factor receptor (EGFR) pathway inhibitors better than mutation status alone. Design Fresh frozen tumour samples from 381 colorectal cancer (CRC) patients were collected and mutations in KRAS, BRAF and PIK3CA were assessed. Using microarray data, three individual oncogenic and a combined model were developed and validated in an independent set of 80 CRC patients, and in a dataset from metastatic CRC patients treated with cetuximab. Results 175 tumours (45.9%) harboured oncogenic mutations in KRAS (30.2%), BRAF (11.0%) and PIK3CA (11.5%). Activating mutation signatures for KRAS (75 genes), for BRAF (58 genes,) and for PIK3CA (49 genes) were developed. The development of a combined oncogenic pathway signature-classified tumours as ‘activated oncogenic’, or as ‘wildtype-like’ with a sensitivity of 90.3% and a specificity of 61.7%. The identified signature revealed other mechanisms that can activate ERK/MAPK pathway in KRAS, BRAF and PIK3CA wildtype patients. The combined signature is associated with response to cetuximab treatment in patients with metastatic CRC (HR 2.51, p<0.0009). Conclusion A combined oncogenic pathway signature allows the identification of patients with an active EGFR-signalling pathway that could benefit from downstream pathway inhibition. PMID:22798500

  20. Oncogenic cancer/testis antigens: prime candidates for immunotherapy.

    PubMed

    Gjerstorff, Morten F; Andersen, Mads H; Ditzel, Henrik J

    2015-06-30

    Recent developments have set the stage for immunotherapy as a supplement to conventional cancer treatment. Consequently, a significant effort is required to further improve efficacy and specificity, particularly the identification of optimal therapeutic targets for clinical testing. Cancer/testis antigens are immunogenic, highly cancer-specific, and frequently expressed in various types of cancer, which make them promising candidate targets for cancer immunotherapy, including cancer vaccination and adoptive T-cell transfer with chimeric T-cell receptors. Our current understanding of tumor immunology and immune escape suggests that targeting oncogenic antigens may be beneficial, meaning that identification of cancer/testis antigens with oncogenic properties is of high priority. Recent work from our lab and others provide evidence that many cancer/testis antigens, in fact, have oncogenic functions, including support of growth, survival and metastasis. This novel insight into the function of cancer/testis antigens has the potential to deliver more effective cancer vaccines. Moreover, immune targeting of oncogenic cancer/testis antigens in combination with conventional cytotoxic therapies or novel immunotherapies such as checkpoint blockade or adoptive transfer, represents a highly synergistic approach with the potential to improve patient survival.

  1. (Oncogenic action of ionizing radiation)

    SciTech Connect

    Not Available

    1990-01-01

    An extensive experiment involving approximately 400 rats exposed to the neon ion beam at the Bevalac in Berkeley, CA and to electrons is nearing completion. The carcinogenicity of energetic electrons was determined for comparison with the neon ion results. As in past reports we will describe progress in three areas corresponding to the specific aims of the proposal: (1) carcinogenesis and DNA strand breaks in rat skin following exposure by the neon ions or electrons; (2) DNA strand breaks in the epidermis as a function of radiation penetration; (3) oncogene activation in radiation-induced rat skin cancers. 72 refs., 6 tabs.

  2. mPGES-1 in prostate cancer controls stemness and amplifies epidermal growth factor receptor-driven oncogenicity.

    PubMed

    Finetti, Federica; Terzuoli, Erika; Giachetti, Antonio; Santi, Raffaella; Villari, Donata; Hanaka, Hiromi; Radmark, Olof; Ziche, Marina; Donnini, Sandra

    2015-08-01

    There is evidence that an inflammatory microenvironment is associated with the development and progression of prostate cancer (PCa), although the determinants of intrinsic inflammation in PCa cells are not completely understood. Here we investigated whether expression of intrinsic microsomal PGE synthase-1 (mPGES-1) enhanced aggressiveness of PCa cells and might be critical for epidermal growth factor receptor (EGFR)-mediated tumour progression. In PCa, overexpression of EGFR promotes metastatic invasion and correlates with a high Gleason score, while prostaglandin E2 (PGE2) has been reported to modulate oncogenic EGFR-driven oncogenicity. Immunohistochemical studies revealed that mPGES-1 in human prostate tissues is correlated with EGFR expression in advanced tumours. In DU145 and PC-3 cell lines expressing mPGES-1 (mPGES-1(SC) cells), we demonstrate that silencing or 'knock down' of mPGES-1 (mPGES-1(KD)) or pharmacological inhibition by MF63 strongly attenuates overall oncogenic drive. Indeed, mPGES-1(SC) cells express stem-cell-like features (high CD44, β1-integrin, Nanog and Oct4 and low CD24 and α6-integrin) as well as mesenchymal transition markers (high vimentin, high fibronectin, low E-cadherin). They also show increased capacity to survive irrespective of anchorage condition, and overexpress EGFR compared to mPGES-1(KD) cells. mPGES-1 expression correlates with increased in vivo tumour growth and metastasis. Although EGFR inhibition reduces mPGES-1(SC) and mPGES-1(KD) cell xenograft tumour growth, we show that mPGES-1/PGE2 signalling sensitizes tumour cells to EGFR inhibitors. We propose mPGES-1 as a possible new marker of tumour aggressiveness in PCa.

  3. mPGES-1 in prostate cancer controls stemness and amplifies epidermal growth factor receptor-driven oncogenicity

    PubMed Central

    Finetti, Federica; Terzuoli, Erika; Giachetti, Antonio; Santi, Raffaella; Villari, Donata; Hanaka, Hiromi; Radmark, Olof; Ziche, Marina; Donnini, Sandra

    2015-01-01

    There is evidence that an inflammatory microenvironment is associated with the development and progression of prostate cancer (PCa), although the determinants of intrinsic inflammation in PCa cells are not completely understood. Here we investigated whether expression of intrinsic microsomal PGE synthase-1 (mPGES-1) enhanced aggressiveness of PCa cells and might be critical for epidermal growth factor receptor (EGFR)-mediated tumour progression. In PCa, overexpression of EGFR promotes metastatic invasion and correlates with a high Gleason score, while prostaglandin E2 (PGE2) has been reported to modulate oncogenic EGFR-driven oncogenicity. Immunohistochemical studies revealed that mPGES-1 in human prostate tissues is correlated with EGFR expression in advanced tumours. In DU145 and PC-3 cell lines expressing mPGES-1 (mPGES-1SC cells), we demonstrate that silencing or ‘knock down’ of mPGES-1 (mPGES-1KD) or pharmacological inhibition by MF63 strongly attenuates overall oncogenic drive. Indeed, mPGES-1SC cells express stem-cell-like features (high CD44, β1-integrin, Nanog and Oct4 and low CD24 and α6-integrin) as well as mesenchymal transition markers (high vimentin, high fibronectin, low E-cadherin). They also show increased capacity to survive irrespective of anchorage condition, and overexpress EGFR compared to mPGES-1KD cells. mPGES-1 expression correlates with increased in vivo tumour growth and metastasis. Although EGFR inhibition reduces mPGES-1SC and mPGES-1KD cell xenograft tumour growth, we show that mPGES-1/PGE2 signalling sensitizes tumour cells to EGFR inhibitors. We propose mPGES-1 as a possible new marker of tumour aggressiveness in PCa. PMID:26113609

  4. Targeting Oncogenic Mutant p53 for Cancer Therapy.

    PubMed

    Parrales, Alejandro; Iwakuma, Tomoo

    2015-01-01

    Among genetic alterations in human cancers, mutations in the tumor suppressor p53 gene are the most common, occurring in over 50% of human cancers. The majority of p53 mutations are missense mutations and result in the accumulation of dysfunctional p53 protein in tumors. These mutants frequently have oncogenic gain-of-function activities and exacerbate malignant properties of cancer cells, such as metastasis and drug resistance. Increasing evidence reveals that stabilization of mutant p53 in tumors is crucial for its oncogenic activities, while depletion of mutant p53 attenuates malignant properties of cancer cells. Thus, mutant p53 is an attractive druggable target for cancer therapy. Different approaches have been taken to develop small-molecule compounds that specifically target mutant p53. These include compounds that restore wild-type conformation and transcriptional activity of mutant p53, induce depletion of mutant p53, inhibit downstream pathways of oncogenic mutant p53, and induce synthetic lethality to mutant p53. In this review article, we comprehensively discuss the current strategies targeting oncogenic mutant p53 in cancers, with special focus on compounds that restore wild-type p53 transcriptional activity of mutant p53 and those reducing mutant p53 levels.

  5. Proteomic analysis of MG132-treated germinating pollen reveals expression signatures associated with proteasome inhibition.

    PubMed

    Vannini, Candida; Bracale, Marcella; Crinelli, Rita; Marconi, Valerio; Campomenosi, Paola; Marsoni, Milena; Scoccianti, Valeria

    2014-01-01

    Chemical inhibition of the proteasome has been previously found to effectively impair pollen germination and tube growth in vitro. However, the mediators of these effects at the molecular level are unknown. By performing 2DE proteomic analysis, 24 differentially expressed protein spots, representing 14 unique candidate proteins, were identified in the pollen of kiwifruit (Actinidia deliciosa) germinated in the presence of the MG132 proteasome inhibitor. qPCR analysis revealed that 11 of these proteins are not up-regulated at the mRNA level, but are most likely stabilized by proteasome inhibition. These differentially expressed proteins are predicted to function in various pathways including energy and lipid metabolism, cell wall synthesis, protein synthesis/degradation and stress responses. In line with this evidence, the MG132-induced changes in the proteome were accompanied by an increase in ATP and ROS content and by an alteration in fatty acid composition.

  6. Gene expression profiles in granuloma tissue reveal novel diagnostic markers in sarcoidosis.

    PubMed

    Christophi, George P; Caza, Tiffany; Curtiss, Christopher; Gumber, Divya; Massa, Paul T; Landas, Steve K

    2014-06-01

    Sarcoidosis is an immune-mediated multisystem disease characterized by the formation of non-caseating granulomas. The pathogenesis of sarcoidosis is unclear, with proposed infectious or environmental antigens triggering an aberrant immune response in susceptible hosts. Multiple pro-inflammatory signaling pathways have been implicated in mediating macrophage activation and granuloma formation in sarcoidosis, including IFN-γ/STAT-1, IL-6/STAT-3, and NF-κB. It is difficult to distinguish sarcoidosis from other granulomatous diseases or assess disease severity and treatment response with histopathology alone. Therefore, development of improved diagnostic tools is imperative. Herein, we describe an efficient and reliable technique to classify granulomatous disease through selected gene expression and identify novel genes and cytokine pathways contributing to the pathogenesis of sarcoidosis. We quantified the expression of twenty selected mRNAs extracted from formalin-fixed paraffin embedded (FFPE) tissue (n = 38) of normal lung, suture granulomas, sarcoid granulomas, and fungal granulomas. Utilizing quantitative real-time RT-PCR we analyzed the expression of several genes, including IL-6, COX-2, MCP-1, IFN-γ, T-bet, IRF-1, Nox2, IL-33, and eotaxin-1 and revealed differential regulation between suture, sarcoidosis, and fungal granulomas. This is the first study demonstrating that quantification of target gene expression in FFPE tissue biopsies is a potentially effective diagnostic and research tool in sarcoidosis.

  7. Dynamic Changes in Amygdala Psychophysiological Connectivity Reveal Distinct Neural Networks for Facial Expressions of Basic Emotions

    PubMed Central

    Diano, Matteo; Tamietto, Marco; Celeghin, Alessia; Weiskrantz, Lawrence; Tatu, Mona-Karina; Bagnis, Arianna; Duca, Sergio; Geminiani, Giuliano; Cauda, Franco; Costa, Tommaso

    2017-01-01

    The quest to characterize the neural signature distinctive of different basic emotions has recently come under renewed scrutiny. Here we investigated whether facial expressions of different basic emotions modulate the functional connectivity of the amygdala with the rest of the brain. To this end, we presented seventeen healthy participants (8 females) with facial expressions of anger, disgust, fear, happiness, sadness and emotional neutrality and analyzed amygdala’s psychophysiological interaction (PPI). In fact, PPI can reveal how inter-regional amygdala communications change dynamically depending on perception of various emotional expressions to recruit different brain networks, compared to the functional interactions it entertains during perception of neutral expressions. We found that for each emotion the amygdala recruited a distinctive and spatially distributed set of structures to interact with. These changes in amygdala connectional patters characterize the dynamic signature prototypical of individual emotion processing, and seemingly represent a neural mechanism that serves to implement the distinctive influence that each emotion exerts on perceptual, cognitive, and motor responses. Besides these differences, all emotions enhanced amygdala functional integration with premotor cortices compared to neutral faces. The present findings thus concur to reconceptualise the structure-function relation between brain-emotion from the traditional one-to-one mapping toward a network-based and dynamic perspective. PMID:28345642

  8. Exon expression profiling reveals stimulus-mediated exon use in neural cells

    PubMed Central

    McKee, Adrienne E; Neretti, Nicola; Carvalho, Luis E; Meyer, Clifford A; Fox, Edward A; Brodsky, Alexander S; Silver, Pamela A

    2007-01-01

    Background: Neuronal cells respond to changes in intracellular calcium ([Ca2+]i) by affecting both the abundance and architecture of specific mRNAs. Although calcium-induced transcription and transcript variation have both been recognized as important sources of gene regulation, the interplay between these two phenomena has not been evaluated on a genome-wide scale. Results: Here, we show that exon-centric microarrays can be used to resolve the [Ca2+]i-modulated gene expression response into transcript-level and exon-level regulation. Global assessments of affected transcripts reveal modulation within distinct functional gene categories. We find that transcripts containing calcium-modulated exons exhibit enrichment for calcium ion binding, calmodulin binding, plasma membrane associated, and metabolic proteins. Additionally, we uncover instances of regulated exon use in potassium channels, neuroendocrine secretory proteins and metabolic enzymes, and demonstrate that regulated changes in exon expression give rise to distinct transcript variants. Conclusion: Our findings connect extracellular stimuli to specific exon behavior, and suggest that changes in transcript and exon abundance are reflective of a coordinated gene expression response to elevated [Ca2+]i. The technology we describe here lends itself readily to the resolution of stimulus-induced gene expression at both the transcript and exon levels. PMID:17683528

  9. Expression Profiling of Primary and Metastatic Ovarian Tumors Reveals Differences Indicative of Aggressive Disease

    PubMed Central

    Brodsky, Alexander S.; Fischer, Andrew; Miller, Daniel H.; Vang, Souriya; MacLaughlan, Shannon; Wu, Hsin-Ta; Yu, Jovian; Steinhoff, Margaret; Collins, Colin; Smith, Peter J. S.; Raphael, Benjamin J.; Brard, Laurent

    2014-01-01

    The behavior and genetics of serous epithelial ovarian cancer (EOC) metastasis, the form of the disease lethal to patients, is poorly understood. The unique properties of metastases are critical to understand to improve treatments of the disease that remains in patients after debulking surgery. We sought to identify the genetic and phenotypic landscape of metastatic progression of EOC to understand how metastases compare to primary tumors. DNA copy number and mRNA expression differences between matched primary human tumors and omental metastases, collected at the same time during debulking surgery before chemotherapy, were measured using microarrays. qPCR and immunohistochemistry validated findings. Pathway analysis of mRNA expression revealed metastatic cancer cells are more proliferative and less apoptotic than primary tumors, perhaps explaining the aggressive nature of these lesions. Most cases had copy number aberrations (CNAs) that differed between primary and metastatic tumors, but we did not detect CNAs that are recurrent across cases. A six gene expression signature distinguishes primary from metastatic tumors and predicts overall survival in independent datasets. The genetic differences between primary and metastatic tumors, yet common expression changes, suggest that the major clone in metastases is not the same as in primary tumors, but the cancer cells adapt to the omentum similarly. Together, these data highlight how ovarian tumors develop into a distinct, more aggressive metastatic state that should be considered for therapy development. PMID:24732363

  10. Dynamic Changes in Amygdala Psychophysiological Connectivity Reveal Distinct Neural Networks for Facial Expressions of Basic Emotions.

    PubMed

    Diano, Matteo; Tamietto, Marco; Celeghin, Alessia; Weiskrantz, Lawrence; Tatu, Mona-Karina; Bagnis, Arianna; Duca, Sergio; Geminiani, Giuliano; Cauda, Franco; Costa, Tommaso

    2017-03-27

    The quest to characterize the neural signature distinctive of different basic emotions has recently come under renewed scrutiny. Here we investigated whether facial expressions of different basic emotions modulate the functional connectivity of the amygdala with the rest of the brain. To this end, we presented seventeen healthy participants (8 females) with facial expressions of anger, disgust, fear, happiness, sadness and emotional neutrality and analyzed amygdala's psychophysiological interaction (PPI). In fact, PPI can reveal how inter-regional amygdala communications change dynamically depending on perception of various emotional expressions to recruit different brain networks, compared to the functional interactions it entertains during perception of neutral expressions. We found that for each emotion the amygdala recruited a distinctive and spatially distributed set of structures to interact with. These changes in amygdala connectional patters characterize the dynamic signature prototypical of individual emotion processing, and seemingly represent a neural mechanism that serves to implement the distinctive influence that each emotion exerts on perceptual, cognitive, and motor responses. Besides these differences, all emotions enhanced amygdala functional integration with premotor cortices compared to neutral faces. The present findings thus concur to reconceptualise the structure-function relation between brain-emotion from the traditional one-to-one mapping toward a network-based and dynamic perspective.

  11. Phaseolin expression in tobacco chloroplast reveals an autoregulatory mechanism in heterologous protein translation.

    PubMed

    De Marchis, Francesca; Bellucci, Michele; Pompa, Andrea

    2016-02-01

    Plastid DNA engineering is a well-established research area of plant biotechnology, and plastid transgenes often give high expression levels. However, it is still almost impossible to predict the accumulation rate of heterologous protein in transplastomic plants, and there are many cases of unsuccessful transgene expression. Chloroplasts regulate their proteome at the post-transcriptional level, mainly through translation control. One of the mechanisms to modulate the translation has been described in plant chloroplasts for the chloroplast-encoded subunits of multiprotein complexes, and the autoregulation of the translation initiation of these subunits depends on the availability of their assembly partners [control by epistasy of synthesis (CES)]. In Chlamydomonas reinhardtii, autoregulation of endogenous proteins recruited in the assembly of functional complexes has also been reported. In this study, we revealed a self-regulation mechanism triggered by the accumulation of a soluble recombinant protein, phaseolin, in the stroma of chloroplast-transformed tobacco plants. Immunoblotting experiments showed that phaseolin could avoid this self-regulation mechanism when targeted to the thylakoids in transplastomic plants. To inhibit the thylakoid-targeted phaseolin translation as well, this protein was expressed in the presence of a nuclear version of the phaseolin gene with a transit peptide. Pulse-chase and polysome analysis revealed that phaseolin mRNA translation on plastid ribosomes was repressed due to the accumulation in the stroma of the same soluble polypeptide imported from the cytosol. We suggest that translation autoregulation in chloroplast is not limited to heteromeric protein subunits but also involves at least some of the foreign soluble recombinant proteins, leading to the inhibition of plastome-encoded transgene expression in chloroplast.

  12. Homologous expression of the Caldicellulosiruptor bescii CelA reveals that the extracellular protein is glycosylated

    DOE PAGES

    Chung, Daehwan; Young, Jenna; Bomble, Yannick J.; ...

    2015-03-23

    Members of the bacterial genus Caldicellulosiruptor are the most thermophilic cellulolytic microbes described with ability to digest lignocellulosic biomass without conventional pretreatment. The cellulolytic ability of different species varies dramatically and correlates with the presence of the multimodular cellulase CelA, which contains both a glycoside hydrolase family 9 endoglucanase and a glycoside hydrolase family 48 exoglucanase known to be synergistic in their activity, connected by three cellulose-binding domains via linker peptides. This architecture exploits the cellulose surface ablation driven by its general cellulase processivity as well as excavates cavities into the surface of the substrate, revealing a novel paradigm formore » cellulase activity. We recently reported that a deletion of celA in C. bescii had a significant effect on its ability to utilize complex biomass. To analyze the structure and function of CelA and its role in biomass deconstruction, we constructed a new expression vector for C. bescii and were able, for the first time, to express significant quantities of full-length protein in vivo in the native host. The protein, which contains a Histidine tag, was active and excreted from the cell. Expression of CelA protein with and without its signal sequence allowed comparison of protein retained intracellularly to protein transported extracellularly. Analysis of protein in culture supernatants revealed that the extracellular CelA protein is glycosylated whereas the intracellular CelA is not, suggesting that either protein transport is required for this post-translational modification or that glycosylation is required for protein export. The mechanism and role of protein glycosylation in bacteria is poorly understood and the ability to express CelA in vivo in C. bescii will allow the study of the mechanism of protein glycosylation in this thermophile. Finally, it will also allow the study of glycosylation of CelA itself and its role

  13. Malignant transformation of diploid human fibroblasts by transfection of oncogenes

    SciTech Connect

    McCormick, J.J.

    1992-01-01

    This document consist of brief reports prepared by postdoctoral students supported by the project, each describing his accomplishments under the grant. Topics include (1) Malignant Transformation of MSU-1. 1 Cells by Gamma Radiation, (2) Correlation between Levels of ras Expression and Presence of Transformed Phenotypes Including Tumorigenicity, Using a Modulatable Promoter, (3) Relation between Specific rad Oncogene Expression, (4) Correlation of Genetic Changes in Fibroblastic Tumors with Malignancies, (5)Transformation of MSU-1.1 Cells by sis Oncogene, (6) Malignant Transformation of MSU-1.0 Cells, (7) Correlation of Urokinase Plasminogen Activation (mu-PA) with Malignant Phenotype, (8)Two Dimensional Gel Electrophoresis Studies of the Proteins of the Major Cell Strains of the MSU-1 Family of Cells, and (9) Correlation between Proteinase Activity Levels and Malignancy.

  14. Monoclonal antibodies reveal multiple forms of expression of human microsomal epoxide hydrolase

    SciTech Connect

    Duan, Hongying; Takagi, Akira; Kayano, Hidekazu; Koyama, Isamu; Morisseau, Christophe; Hammock, Bruce D.; Akatsuka, Toshitaka

    2012-04-01

    In a previous study, we developed five kinds of monoclonal antibodies against different portions of human mEH: three, anti-N-terminal; one, anti-C-terminal; one, anti-conformational epitope. Using them, we stained the intact and the permeabilized human cells of various kinds and performed flow cytometric analysis. Primary hepatocytes and peripheral blood mononuclear cells (PBMC) showed remarkable differences. On the surface, hepatocytes exhibited 4 out of 5 epitopes whereas PBMC did not show any of the epitopes. mEH was detected inside both cell types, but the most prominent expression was observed for the conformational epitope in the hepatocytes and the two N-terminal epitopes in PBMC. These differences were also observed between hepatocyte-derived cell lines and mononuclear cell-derived cell lines. In addition, among each group, there were several differences which may be related to the cultivation, the degree of differentiation, or the original cell subsets. We also noted that two glioblastoma cell lines reveal marked expression of the conformational epitope on the surface which seemed to correlate with the brain tumor-associated antigen reported elsewhere. Several cell lines also underwent selective permeabilization before flow cytometric analysis, and we noticed that the topological orientation of mEH on the ER membrane in those cells was in accordance with the previous report. However, the orientation on the cell surface was inconsistent with the report and had a great variation between the cells. These findings show the multiple mode of expression of mEH which may be possibly related to the multiple roles that mEH plays in different cells. -- Highlights: ► We examine expression of five mEH epitopes in human cells. ► Remarkable differences exist between hepatocytes and PBMC. ► mEH expression in cell lines differs depending on several factors. ► Some glioblastoma cell lines reveal marked surface expression of mEH. ► Topology of mEH on the cell

  15. K-ras oncogene mutation in pterygium.

    PubMed

    Ozturk, B T; Yıldırım, M S; Zamani, A; Bozkurt, B

    2017-03-01

    PurposePterygium is claimed to be a benign proliferation triggered by prolonged exposure to ultraviolet radiation. The frequency of K-ras oncogene mutation, which is among the initial mutations in tumorigenesis, is evaluated in this study.Patients and methodsIn this prospective randomized clinical, trial pterygium tissues and normal conjunctiva tissue specimens are obtained from the superotemporal quadrant of patients who underwent primary pterygium excision with autograft transplantation. DNA extraction from tissues was performed using the QIAamp DNA FFPE tissue kit. A PCR reaction was performed to amplify sequences containing codons 12, 13, and 61 of the K-ras gene in DNA. These PCR products then underwent the 'pyrosequencing' procedure for mutations at these codons.ResultsPterygium and normal conjunctival tissue samples of 25 patients (10 females, 15 males) were evaluated in the study. The mean age of the patients was 54.54±13.13 years. Genetic analysis revealed no K-ras mutations in normal conjunctival tissues, whereas pterygium tissues of the same cases demonstrated mutation at codon 12 in one case and mutations at codon 61 in seven cases, which was statistically significant (P<0.05). The point missense mutations at codon 61 were glutamine to arginine (Glu61Arg CAA>CGA) in four cases and glutamine to leucine (Glu61Leu CAA>CTA) in three cases.ConclusionThe significantly higher frequency of codon 61 mutation of the ras oncogene in primary and bilateral pterygium specimens compared with normal conjunctiva supports the tumoral origin of pterygium, and thus set the stage for research into a targeted therapy for pterygium with better outcomes than surgical excision.

  16. ARF and ATM/ATR cooperate in p53-mediated apoptosis upon oncogenic stress

    SciTech Connect

    Pauklin, Siim . E-mail: spauklin@ut.ee; Kristjuhan, Arnold; Maimets, Toivo; Jaks, Viljar

    2005-08-26

    Induction of apoptosis is pivotal for eliminating cells with damaged DNA or deregulated proliferation. We show that tumor suppressor ARF and ATM/ATR kinase pathways cooperate in the induction of apoptosis in response to elevated expression of c-myc, {beta}-catenin or human papilloma virus E7 oncogenes. Overexpression of oncogenes leads to the formation of phosphorylated H2AX foci, induction of Rad51 protein levels and ATM/ATR-dependent phosphorylation of p53. Inhibition of ATM/ATR kinases abolishes both induction of Rad51 and phosphorylation of p53, and remarkably reduces the level of apoptosis induced by co-expression of oncogenes and ARF. However, the induction of apoptosis is downregulated in p53-/- cells and does not depend on activities of ATM/ATR kinases, indicating that efficient induction of apoptosis by oncogene activation depends on coordinated action of ARF and ATM/ATR pathways in the regulation of p53.

  17. In vivo quantification and perturbation of Myc-Max interactions and the impact on oncogenic potential.

    PubMed

    Raffeiner, Philipp; Röck, Ruth; Schraffl, Andrea; Hartl, Markus; Hart, Jonathan R; Janda, Kim D; Vogt, Peter K; Stefan, Eduard; Bister, Klaus

    2014-10-15

    The oncogenic bHLH-LZ transcription factor Myc forms binary complexes with its binding partner Max. These and other bHLH-LZ-based protein-protein interactions (PPI) in the Myc-Max network are essential for the physiological and oncogenic activities of Myc. We have generated a genetically determined and highly specific protein-fragment complementation assay based on Renilla luciferase to analyze the dynamic interplay of bHLH-LZ transcription factors Myc, Max, and Mxd1 in vivo. We also applied this PPI reporter to quantify alterations of nuclear Myc-Max complexes in response to mutational events, competitive binding by the transcriptional repressor Mxd1, or perturbations by small-molecule Myc inhibitors, including recently identified potent PPI inhibitors from a Kröhnke pyridine library. We show that the specificity of Myc-Max PPI reduction by the pyridine inhibitors directly correlates with their efficient and highly specific potential to interfere with the proliferation of human and avian tumor cells displaying deregulated Myc expression. In a direct comparison with known Myc inhibitors using human and avian cell systems, the pyridine compounds reveal a unique inhibitory potential even at sub-micromolar concentrations combined with remarkable specificity for the inhibition of Myc-driven tumor cell proliferation. Furthermore, we show in direct comparisons using defined avian cell systems that different Max PPI profiles for the variant members of the Myc protein family (c-Myc, v-Myc, N-Myc, L-Myc) correlate with their diverse oncogenic potential and their variable sensitivity to the novel pyridine inhibitors.

  18. Molecular Expression Profile Reveals Potential Biomarkers and Therapeutic Targets in Canine Endometrial Lesions

    PubMed Central

    Voorwald, Fabiana Azevedo; Marchi, Fabio Albuquerque; Villacis, Rolando Andre Rios; Alves, Carlos Eduardo Fonseca; Toniollo, Gilson Hélio; Amorim, Renee Laufer

    2015-01-01

    Cystic endometrial hyperplasia (CEH), mucometra, and pyometra are common uterine diseases in intact dogs, with pyometra being a life threatening disease. This study aimed to determine the gene expression profile of these lesions and potential biomarkers for closed-cervix pyometra, the most severe condition. Total RNA was extracted from 69 fresh endometrium samples collected from 21 healthy female dogs during diestrus, 16 CEH, 15 mucometra and 17 pyometra (eight open and nine closed-cervixes). Global gene expression was detected using the Affymetrix Canine Gene 1.0 ST Array. Unsupervised analysis revealed two clusters, one mainly composed of diestrus and CEH samples and the other by 12/15 mucometra and all pyometra samples. When comparing pyometra with other groups, 189 differentially expressed genes were detected. SLPI, PTGS2/COX2, MMP1, S100A8, S100A9 and IL8 were among the top up-regulated genes detected in pyometra, further confirmed by external expression data. Notably, a particular molecular profile in pyometra from animals previously treated with exogenous progesterone compounds was observed in comparison with pyometra from untreated dogs as well as with other groups irrespective of exogenous hormone treatment status. In addition to S100A8 and S100A9 genes, overexpression of the inflammatory cytokines IL1B, TNF and IL6 as well as LTF were detected in the pyometra from treated animals. Interestingly, closed pyometra was more frequently detected in treated dogs (64% versus 33%), with IL1B, TNF, LBP and CXCL10 among the most relevant overexpressed genes. This molecular signature associated with potential biomarkers and therapeutic targets, such as CXCL10 and COX2, should guide future clinical studies. Based on the gene expression profile we suggested that pyometra from progesterone treated dogs is a distinct molecular entity. PMID:26222498

  19. Analysis of the interplay between methylation and expression reveals its potential role in cancer aetiology.

    PubMed

    Ozer, Bugra; Sezerman, Ugur

    2017-01-01

    With ongoing developments in technology, changes in DNA methylation levels have become prevalent to study cancer biology. Previous studies report that DNA methylation affects gene expression in a direct manner, most probably by blocking gene regulatory regions. In this study, we have studied the interplay between methylation and expression to improve our knowledge of cancer aetiology. For this purpose, we have investigated which genomic regions are of higher importance; hence, first exon, 5'UTR and 200 bp near the transcription start sites are proposed as being more crucial compared to other genomic regions. Furthermore, we have searched for a valid methylation level change threshold, and as a result, 25 % methylation change in previously determined genomic regions showed the highest inverse correlation with expression data. As a final step, we have examined the commonly affected genes and pathways by integrating methylation and expression information. Remarkably, the GPR115 gene and ErbB signalling pathway were found to be significantly altered for all cancer types in our analysis. Overall, combining methylation and expression information and identifying commonly affected genes and pathways in a variety of cancer types revealed new insights of cancer disease mechanisms. Moreover, compared to previous methylation-based studies, we have identified more important genomic regions and have defined a methylation change threshold level in order to obtain more reliable results. In addition to the novel analysis framework that involves the analysis of four different cancer types, our study exposes essential information regarding the contribution of methylation changes and its impact on cancer disease biology, which may facilitate the identification of new drug targets.

  20. Marker expression reveals heterogeneity of spermatogonia in the neonatal mouse testis.

    PubMed

    Niedenberger, Bryan A; Busada, Jonathan T; Geyer, Christopher B

    2015-04-01

    Prospermatogonia transition to type A spermatogonia, which provide the source for the spermatogonial stem cell (SSC) pool. A percentage of these type A spermatogonia then differentiate to enter meiosis as spermatocytes by ∼P10. It is currently unclear as to when these distinct populations are initially formed in the neonatal testis, and when the expression of markers both characteristic of and required for the adult undifferentiated and differentiating states is established. In this study, we compared expression of known spermatogonial cell fate markers during normal development and in response to the differentiation signal provided by retinoic acid (RA). We found that some markers for the undifferentiated state (ZBTB16/PLZF and CDH1) were expressed in nearly all spermatogonia from P1 through P7. In contrast, differentiation markers (STRA8 and KIT) appeared in a subset of spermatogonia at P4, coincident with the onset of RA signaling. GFRA1, which was present in nearly all prospermatogonia at P1, was only retained in STRA8/KIT- spermatogonia. From P4 through P10, there was a great deal of heterogeneity in the male germ cell population in terms of expression of markers, as markers characteristic of the undifferentiated (except GFRA1) and differentiating states were co-expressed through this interval. After P10, these fate markers diverged to mark distinct populations of undifferentiated and differentiating spermatogonia, and this pattern was maintained in juvenile (P18) and adult (P>60) testes. Taken together, these results reveal that the spermatogonia population is heterogeneous during the first wave of spermatogenesis, and indicate that neonatal spermatogonia may not serve as an ideal substitute for studying the function of adult spermatogonia.

  1. Gene expression analysis of biopsy samples reveals critical limitations of transcriptome‐based molecular classifications of hepatocellular carcinoma

    PubMed Central

    Makowska, Zuzanna; Boldanova, Tujana; Adametz, David; Quagliata, Luca; Vogt, Julia E.; Dill, Michael T.; Matter, Mathias S.; Roth, Volker; Terracciano, Luigi

    2016-01-01

    Abstract Molecular classification of hepatocellular carcinomas (HCC) could guide patient stratification for personalized therapies targeting subclass‐specific cancer ‘driver pathways’. Currently, there are several transcriptome‐based molecular classifications of HCC with different subclass numbers, ranging from two to six. They were established using resected tumours that introduce a selection bias towards patients without liver cirrhosis and with early stage HCCs. We generated and analyzed gene expression data from paired HCC and non‐cancerous liver tissue biopsies from 60 patients as well as five normal liver samples. Unbiased consensus clustering of HCC biopsy profiles identified 3 robust classes. Class membership correlated with survival, tumour size and with Edmondson and Barcelona Clinical Liver Cancer (BCLC) stage. When focusing only on the gene expression of the HCC biopsies, we could validate previously reported classifications of HCC based on expression patterns of signature genes. However, the subclass‐specific gene expression patterns were no longer preserved when the fold‐change relative to the normal tissue was used. The majority of genes believed to be subclass‐specific turned out to be cancer‐related genes differentially regulated in all HCC patients, with quantitative rather than qualitative differences between the molecular subclasses. With the exception of a subset of samples with a definitive β‐catenin gene signature, biological pathway analysis could not identify class‐specific pathways reflecting the activation of distinct oncogenic programs. In conclusion, we have found that gene expression profiling of HCC biopsies has limited potential to direct therapies that target specific driver pathways, but can identify subgroups of patients with different prognosis. PMID:27499918

  2. Immune responsive gene 1, a novel oncogene, increases the growth and tumorigenicity of glioma.

    PubMed

    Pan, Jun; Zhao, Xiaoyong; Lin, Chunnan; Xu, Hongchao; Yin, Zhilin; Liu, Tianzhu; Zhang, Shizhong

    2014-11-01

    Immune responsive gene 1 (IRG1) is highly expressed in mammalian macrophages during inflammation. However, the role of IRG1 in tumorigenesis remains unclear. In the present study, we aimed to clarify the epigenetic regulation and biological functions of IRG1 in glioma. We found that the expression level of IRG1 influenced the WHO stage in 140 glioma patients. Overexpression of IRG1 increased the growth, invasion, and tumorigenesis in U251 and SHG-44 glioma cells both in vitro and in vivo. Suppression of IRG1 expression by si-IRG1 decreased the levels of cell cycle regulatory proteins, namely, E2F1, p21, CDK4, CDK6 and cyclin D1. Knockdown of IRG1 expression by RNA interference increased E-cadherin expression and decreased the amounts of snail and vimentin. Furthermore, the suppression of IRG1 expression inhibited the expression of NF-κB and STAT3, suggesting a role of IRG1 in regulating the genes associated with these factors and thereby contributing to a decrease in glioma cell proliferation, migration and invasion. Collectively, our findings revealed that IRG1 is a candidate oncogene that is amplified in glioma and is involved in novel mechanisms that influence glioma pathogenesis.

  3. Differentially expressed genes and interacting pathways in bladder cancer revealed by bioinformatic analysis.

    PubMed

    Shen, Yinzhou; Wang, Xuelei; Jin, Yongchao; Lu, Jiasun; Qiu, Guangming; Wen, Xiaofei

    2014-10-01

    The goal of this study was to identify cancer-associated differentially expressed genes (DEGs), analyze their biological functions and investigate the mechanism(s) of cancer occurrence and development, which may provide a theoretical foundation for bladder cancer (BCa) therapy. We downloaded the mRNA expression profiling dataset GSE13507 from the Gene Expression Omnibus database; the dataset includes 165 BCa and 68 control samples. T‑tests were used to identify DEGs. To further study the biological functions of the identified DEGs, we performed a Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Next, we built a network of potentially interacting pathways to study the synergistic relationships among DEGs. A total of 12,105 genes were identified as DEGs, of which 5,239 were upregulated and 6,866 were downregulated in BCa. The DEGs encoding activator protein 1 (AP-1), nuclear factor of activated T-cells (NFAT) proteins, nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) and interleukin (IL)-10 were revealed to participate in the significantly enriched immune pathways that were downregulated in BCa. KEGG enrichment analysis revealed 7 significantly upregulated and 47 significantly downregulated pathways enriched among the DEGs. We found a crosstalk interaction among a total of 44 pathways in the network of BCa-affected pathways. In conclusion, our results show that BCa involves dysfunctions in multiple systems. Our study is expected to pave ways for immune and inflammatory research and provide molecular insights for cancer therapy.

  4. RNA-Seq profiling reveals novel hepatic gene expression pattern in aflatoxin B1 treated rats.

    PubMed

    Merrick, B Alex; Phadke, Dhiral P; Auerbach, Scott S; Mav, Deepak; Stiegelmeyer, Suzy M; Shah, Ruchir R; Tice, Raymond R

    2013-01-01

    Deep sequencing was used to investigate the subchronic effects of 1 ppm aflatoxin B1 (AFB1), a potent hepatocarcinogen, on the male rat liver transcriptome prior to onset of histopathological lesions or tumors. We hypothesized RNA-Seq would reveal more differentially expressed genes (DEG) than microarray analysis, including low copy and novel transcripts related to AFB1's carcinogenic activity compared to feed controls (CTRL). Paired-end reads were mapped to the rat genome (Rn4) with TopHat and further analyzed by DESeq and Cufflinks-Cuffdiff pipelines to identify differentially expressed transcripts, new exons and unannotated transcripts. PCA and cluster analysis of DEGs showed clear separation between AFB1 and CTRL treatments and concordance among group replicates. qPCR of eight high and medium DEGs and three low DEGs showed good comparability among RNA-Seq and microarray transcripts. DESeq analysis identified 1,026 differentially expressed transcripts at greater than two-fold change (p<0.005) compared to 626 transcripts by microarray due to base pair resolution of transcripts by RNA-Seq, probe placement within transcripts or an absence of probes to detect novel transcripts, splice variants and exons. Pathway analysis among DEGs revealed signaling of Ahr, Nrf2, GSH, xenobiotic, cell cycle, extracellular matrix, and cell differentiation networks consistent with pathways leading to AFB1 carcinogenesis, including almost 200 upregulated transcripts controlled by E2f1-related pathways related to kinetochore structure, mitotic spindle assembly and tissue remodeling. We report 49 novel, differentially-expressed transcripts including confirmation by PCR-cloning of two unique, unannotated, hepatic AFB1-responsive transcripts (HAfT's) on chromosomes 1.q55 and 15.q11, overexpressed by 10 to 25-fold. Several potentially novel exons were found and exon refinements were made including AFB1 exon-specific induction of homologous family members, Ugt1a6 and Ugt1a7c. We find the

  5. Comparative expression profiling reveals an essential role for raldh2 in epimorphic regeneration.

    PubMed

    Mathew, Lijoy K; Sengupta, Sumitra; Franzosa, Jill A; Perry, Jessica; La Du, Jane; Andreasen, Eric A; Tanguay, Robert L

    2009-11-27

    Zebrafish have the remarkable ability to regenerate body parts including the heart and fins by a process referred to as epimorphic regeneration. Recent studies have illustrated that similar to adult zebrafish, early life stage larvae also possess the ability to regenerate the caudal fin. A comparative microarray analysis was used to determine the degree of conservation in gene expression among the regenerating adult caudal fin, adult heart, and larval fin. Results indicate that these tissues respond to amputation/injury with strikingly similar genomic responses. Comparative analysis revealed raldh2, a rate-limiting enzyme for the synthesis of retinoic acid, as one of the most highly induced genes across the three regeneration platforms. In situ localization and functional studies indicate that raldh2 expression is critical for the formation of wound epithelium and blastema. Patterning during regenerative outgrowth was considered to be the primary function of retinoic acid signaling; however, our results suggest that it is also required for early stages of tissue regeneration. Expression of raldh2 is regulated by Wnt and fibroblast growth factor/ERK signaling.

  6. sdf1 Expression Reveals a Source of Perivascular-Derived Mesenchymal Stem Cells in Zebrafish

    PubMed Central

    Lund, Troy C.; Patrinostro, Xiaobai; Kramer, Ashley C.; Stadem, Paul; Higgins, LeeAnn; Markowski, Todd W.; Wroblewski, Matt S.; Lidke, Diane S.; Tolar, Jakub; Blazar, Bruce R.

    2014-01-01

    There is accumulating evidence that mesenchymal stem cells (MSC) have their origin as perivascular cells (PVC) in vivo, but precisely identifying them has been a challenge, as they have no single definitive marker and are rare. We have developed a fluorescent transgenic vertebrate model in which PVC can be visualized in vivo based upon sdf1 expression in the zebrafish. Prospective isolation and culture of sdf1DsRed PVC demonstrated properties consistent with MSC including prototypical cell surface marker expression; mesodermal differentiation into adipogenic, osteogenic and chondrogenic lineages; and the ability to support hematopoietic cells. Global proteomic studies performed by 2-dimensional liquid chromatography and tandem mass spectrometry revealed a high degree of similarity to human MSC and discovery of novel markers (CD99, CD151 and MYOF) that were previously unknown to be expressed by hMSC. Dynamic in vivo imaging during fin regeneration showed that PVC may arise from undifferentiated mesenchyme providing evidence of a PVC – MSC relationship. This is the first model, established in zebrafish, in which MSC can be visualized in vivo and will allow us to better understand their function in a native environment. PMID:24905975

  7. Comparative expression profiling reveals gene functions in female meiosis and gametophyte development in Arabidopsis.

    PubMed

    Zhao, Lihua; He, Jiangman; Cai, Hanyang; Lin, Haiyan; Li, Yanqiang; Liu, Renyi; Yang, Zhenbiao; Qin, Yuan

    2014-11-01

    Megasporogenesis is essential for female fertility, and requires the accomplishment of meiosis and the formation of functional megaspores. The inaccessibility and low abundance of female meiocytes make it particularly difficult to elucidate the molecular basis underlying megasporogenesis. We used high-throughput tag-sequencing analysis to identify genes expressed in female meiocytes (FMs) by comparing gene expression profiles from wild-type ovules undergoing megasporogenesis with those from the spl mutant ovules, which lack megasporogenesis. A total of 862 genes were identified as FMs, with levels that are consistently reduced in spl ovules in two biological replicates. Fluorescence-assisted cell sorting followed by RNA-seq analysis of DMC1:GFP-labeled female meiocytes confirmed that 90% of the FMs are indeed detected in the female meiocyte protoplast profiling. We performed reverse genetic analysis of 120 candidate genes and identified four FM genes with a function in female meiosis progression in Arabidopsis. We further revealed that KLU, a putative cytochrome P450 monooxygenase, is involved in chromosome pairing during female meiosis, most likely by affecting the normal expression pattern of DMC1 in ovules during female meiosis. Our studies provide valuable information for functional genomic analyses of plant germline development as well as insights into meiosis.

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

    PubMed

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

    2017-02-17

    RUNX3, runt-domain transcription factor, is a master regulator of gene expression in major developmental pathways. It acts as a tumor suppressor in many cancers but is oncogenic in certain tumors. We observed upregulation of RUNX3 mRNA and protein expression in nasal-type extranodal natural killer (NK)/T-cell lymphoma (NKTL) patient samples and NKTL cell lines compared to normal NK cells. RUNX3 silenced NKTL cells showed increased apoptosis and reduced cell proliferation. Potential binding sites for MYC were identified in the RUNX3 enhancer region. Chromatin immunoprecipitation-quantitative PCR revealed binding activity between MYC and RUNX3. Co-transfection of the MYC expression vector with RUNX3 enhancer reporter plasmid resulted in activation of RUNX3 enhancer indicating that MYC positively regulates RUNX3 transcription in NKTL cell lines. Treatment with a small-molecule MYC inhibitor (JQ1) caused significant downregulation of MYC and RUNX3, leading to apoptosis in NKTL cells. The growth inhibition resulting from depletion of MYC by JQ1 was rescued by ectopic MYC expression. In summary, our study identified RUNX3 overexpression in NKTL with functional oncogenic properties. We further delineate that MYC may be an important upstream driver of RUNX3 upregulation and since MYC is upregulated in NKTL, further study on the employment of MYC inhibition as a therapeutic strategy is warranted.Leukemia advance online publication, 17 February 2017; doi:10.1038/leu.2017.40.

  9. Oncogenic K-Ras and Basic Fibroblast Growth Factor Prevent FAS-Mediated Apoptosis in Fibroblasts through Activation of Mitogen-Activated Protein Kinase

    PubMed Central

    Kazama, Hirotaka; Yonehara, Shin

    2000-01-01

    By an expression cloning method using Fas-transgenic Balb3T3 cells, we tried to obtain inhibitory genes against Fas-mediated apoptosis and identified proto-oncogene c-K-ras. Transient expression of K-Ras mutants revealed that oncogenic mutant K-Ras (RasV12) strongly inhibited, whereas dominant-inhibitory mutant K-Ras (RasN17) enhanced, Fas-mediated apoptosis by inhibiting Fas-triggered activation of caspases without affecting an expression level of Fas. Among the target molecules of Ras, including Raf (mitogen-activated protein kinase kinase kinase [MAPKKK]), phosphatidylinositol 3 (PI-3) kinase, and Ral guanine nucleotide exchange factor (RalGDS), only the constitutively active form of Raf (Raf-CAAX) could inhibit Fas-mediated apoptosis. In addition, the constitutively active form of MAPKK (SDSE-MAPKK) suppressed Fas-mediated apoptosis, and MKP-1, a phosphatase specific for classical MAPK, canceled the protective activity of oncogenic K-Ras (K-RasV12), Raf-CAAX, and SDSE-MAPKK. Furthermore, physiological activation of Ras by basic fibroblast growth factor (bFGF) protected Fas-transgenic Balb3T3 cells from Fas-mediated apoptosis. bFGF protection was also dependent on the activation of the MAPK pathway through Ras. All the results indicate that the activation of MAPK through Ras inhibits Fas-mediated apoptosis in Balb3T3 cells, which may play a role in oncogenesis. PMID:10662780

  10. Oncogenic effects of evolutionarily conserved noncoding RNA ECONEXIN on gliomagenesis.

    PubMed

    Deguchi, S; Katsushima, K; Hatanaka, A; Shinjo, K; Ohka, F; Wakabayashi, T; Zong, H; Natsume, A; Kondo, Y

    2017-04-03

    Accumulating studies have demonstrated the importance of long noncoding RNAs (lncRNAs) during oncogenic transformation. However, because most lncRNAs are currently uncharacterized, the identification of novel oncogenic lncRNAs is difficult. Given that intergenic lncRNA have substantially less sequence conservation patterns than protein-coding genes across species, evolutionary conserved intergenic lncRNAs are likely to be functional. The current study identified a novel intergenic lncRNA, LINC00461 (ECONEXIN) using a combined approach consisting of searching lncRNAs by evolutionary conservation and validating their expression in a glioma mouse model. ECONEXIN was the most highly conserved intergenic lncRNA containing 83.0% homology with the mouse ortholog (C130071C03Rik) for a region over 2500 bp in length within its exon 3. Expressions of ECONEXIN and C130071C03Rik were significantly upregulated in both human and mouse glioma tissues. Moreover, the expression of C130071C03Rik was upregulated even in precancerous conditions and markedly increased during glioma progression. Functional analysis of ECONEXIN in glioma cell lines, U87 and U251, showed it was dominantly located in the cytoplasm and interacted with miR-411-5p via two binding sites within ECONEXIN. Inhibition of ECONEXIN upregulated miR-411-5p together with the downregulation of its target, Topoisomerase 2 alpha (TOP2A), in glioma cell lines, resulting in decreased cell proliferation. Our data demonstrated that ECONEXIN is a potential oncogene that regulates TOP2A by sponging miR-411-5p in glioma. In addition, our investigative approaches to identify conserved lncRNA and their molecular characterization by validation in mouse tumor models may be useful to functionally annotate novel lncRNAs, especially cancer-associated lncRNAs.Oncogene advance online publication, 3 April 2017; doi:10.1038/onc.2017.88.

  11. RUNX3 is a novel negative regulator of oncogenic TEAD-YAP complex in gastric cancer.

    PubMed

    Qiao, Y; Lin, S J; Chen, Y; Voon, D C-C; Zhu, F; Chuang, L S H; Wang, T; Tan, P; Lee, S C; Yeoh, K G; Sudol, M; Ito, Y

    2016-05-19

    Runt-related transcription factor 3 (RUNX3) is a well-documented tumour suppressor that is frequently inactivated in gastric cancer. Here, we define a novel mechanism by which RUNX3 exerts its tumour suppressor activity involving the TEAD-YAP complex, a potent positive regulator of proliferative genes. We report that the TEAD-YAP complex is not only frequently hyperactivated in liver and breast cancer, but also confers a strong oncogenic activity in gastric epithelial cells. The increased expression of TEAD-YAP in tumour tissues significantly correlates with poorer overall survival of gastric cancer patients. Strikingly, RUNX3 physically interacts with the N-terminal region of TEAD through its Runt domain. This interaction markedly reduces the DNA-binding ability of TEAD that attenuates the downstream signalling of TEAD-YAP complex. Mutation of RUNX3 at Arginine 122 to Cysteine, which was previously identified in gastric cancer, impairs the interaction between RUNX3 and TEAD. Our data reveal that RUNX3 acts as a tumour suppressor by negatively regulating the TEAD-YAP oncogenic complex in gastric carcinogenesis.

  12. Activation of the JNK pathway is essential for transformation by the Met oncogene.

    PubMed Central

    Rodrigues, G A; Park, M; Schlessinger, J

    1997-01-01

    The Met/Hepatocyte Growth Factor (HGF) receptor tyrosine kinase is oncogenically activated through a rearrangement that creates a hybrid gene Tpr-Met. The resultant chimeric p65(Tpr-Met) protein is constitutively phosphorylated on tyrosine residues in vivo and associates with a number of SH2-containing signaling molecules including the p85 subunit of PI-3 kinase and the Grb2 adaptor protein, which couples receptor tyrosine kinases to the Ras signaling pathway. Mutation of the binding site for Grb2 impairs the ability of Tpr-Met oncoprotein to transform fibroblasts, suggesting that the activation of the Ras/MAP kinase signaling pathway through Grb2 may be essential for cellular transformation. To test this hypothesis dominant-negative mutants of Grb2 with deletions of the SH3 domains were introduced into Tpr-Met transformed fibroblasts. Cells overexpressing the mutants were found to be morphologically reverted and exhibited reduced growth in soft agar. Surprisingly, the Grb2 mutants blocked activation of the JNK/SAPK but not MAP kinase activity induced by the Tpr-Met oncoprotein. Additionally, cells expressing dominant-negative Grb2 mutants had reduced PI-3-kinase activity and dominant-negative mutants of Rac1 blocked both Tpr-Met-induced transformation and activation of JNK. These experiments reveal a novel link between Met and the JNK pathway, which is essential for transformation by this oncogene. PMID:9184210

  13. Genome-wide gene expression profiling reveals unsuspected molecular alterations in pemphigus foliaceus

    PubMed Central

    Malheiros, Danielle; Panepucci, Rodrigo A; Roselino, Ana M; Araújo, Amélia G; Zago, Marco A; Petzl-Erler, Maria Luiza

    2014-01-01

    Pemphigus foliaceus (PF) is a complex autoimmune disease characterized by bullous skin lesions and the presence of antibodies against desmoglein 1. In this study we sought to contribute to a better understanding of the molecular processes in endemic PF, as the identification of factors that participate in the pathogenesis is a prerequisite for understanding its biological basis and may lead to novel therapeutic interventions. CD4+ T lymphocytes are central to the development of the disease. Therefore, we compared genome-wide gene expression profiles of peripheral CD4+ T cells of various PF patient subgroups with each other and with that of healthy individuals. The patient sample was subdivided into three groups: untreated patients with the generalized form of the disease, patients submitted to immunosuppressive treatment, and patients with the localized form of the disease. Comparisons between different subgroups resulted in 135, 54 and 64 genes differentially expressed. These genes are mainly related to lymphocyte adhesion and migration, apoptosis, cellular proliferation, cytotoxicity and antigen presentation. Several of these genes were differentially expressed when comparing lesional and uninvolved skin from the same patient. The chromosomal regions 19q13 and 12p13 concentrate differentially expressed genes and are candidate regions for PF susceptibility genes and disease markers. Our results reveal genes involved in disease severity, potential therapeutic targets and previously unsuspected processes involved in the pathogenesis. Besides, this study adds original information that will contribute to the understanding of PF's pathogenesis and of the still poorly defined in vivo functions of most of these genes. PMID:24813052

  14. Gene expression profiling of epithelial ovarian cancer reveals key genes and pathways associated with chemotherapy resistance.

    PubMed

    Zhang, M; Luo, S C

    2016-01-22

    The aim of this study is to analyze gene expression data to identify key genes and pathways associated with resistance to platinum-based chemotherapy in epithelial ovarian cancer (EOC) and to improve clinical treatment strategies. The gene expression data set was downloaded from Gene Expression Omnibus and included 12 chemotherapy-resistant EOC samples and 16 chemotherapy-sensitive EOC samples. A differential analysis was performed to screen out differentially expressed genes (DEGs). A functional enrichment analysis was conducted for the DEGs using the database for annotation, visualization, and integration discovery. A protein-protein interaction (PPI) network was constructed with information from the human protein reference database. Pathway-pathway interactions were determined with a test based on the hypergeometric distribution. A total of 1564 DEGs were identified in chemotherapy-sensitive EOC, including 654 upregulated genes and 910 downregulated genes. The top three upregulated genes were HIST1H3G, AKT3, and RTN3, while the top three downregulated genes were NBLA00301, TRIM62, and EPHA5. A Gene Ontology enrichment analysis showed that cell adhesion, biological adhesion, and intracellular signaling cascades were significantly enriched in the DEGs. A KEGG pathway enrichment analysis revealed that the calcium, mitogen-activated protein kinase, and B cell receptor signaling pathways were significantly over-represented in the DEGs. A PPI network containing 101 interactions was acquired. The top three hub genes were RAC1, CAV1, and BCL2. Five modules were identified from the PPI network. Taken together, these findings could advance the understanding of the molecular mechanisms underlying intrinsic chemotherapy resistance in EOC.

  15. Subtractive transcriptome analysis of leaf and rhizome reveals differentially expressed transcripts in Panax sokpayensis.

    PubMed

    Gurung, Bhusan; Bhardwaj, Pardeep K; Talukdar, Narayan C

    2016-11-01

    In the present study, suppression subtractive hybridization (SSH) strategy was used to identify rare and differentially expressed transcripts in leaf and rhizome tissues of Panax sokpayensis. Out of 1102 randomly picked clones, 513 and 374 high quality expressed sequenced tags (ESTs) were generated from leaf and rhizome subtractive libraries, respectively. Out of them, 64.92 % ESTs from leaf and 69.26 % ESTs from rhizome SSH libraries were assembled into different functional categories, while others were of unknown function. In particular, ESTs encoding galactinol synthase 2, ribosomal RNA processing Brix domain protein, and cell division cycle protein 20.1, which are involved in plant growth and development, were most abundant in the leaf SSH library. Other ESTs encoding protein KIAA0664 homologue, ubiquitin-activating enzyme e11, and major latex protein, which are involved in plant immunity and defense response, were most abundant in the rhizome SSH library. Subtractive ESTs also showed similarity with genes involved in ginsenoside biosynthetic pathway, namely farnesyl pyrophosphate synthase, squalene synthase, and dammarenediol synthase. Expression profiles of selected ESTs validated the quality of libraries and confirmed their differential expression in the leaf, stem, and rhizome tissues. In silico comparative analyses revealed that around 13.75 % of unigenes from the leaf SSH library were not represented in the available leaf transcriptome of Panax ginseng. Similarly, around 18.12, 23.75, 25, and 6.25 % of unigenes from the rhizome SSH library were not represented in available root/rhizome transcriptomes of P. ginseng, Panax notoginseng, Panax quinquefolius, and Panax vietnamensis, respectively, indicating a major fraction of novel ESTs. Therefore, these subtractive transcriptomes provide valuable resources for gene discovery in P. sokpayensis and would complement the available transcriptomes from other Panax species.

  16. Multiple oncogenic mutations and clonal relationship in spatially distinct benign human epidermal tumors

    PubMed Central

    Hafner, Christian; Toll, Agustí; Fernández-Casado, Alejandro; Earl, Julie; Marqués, Miriam; Acquadro, Francesco; Méndez-Pertuz, Marinela; Urioste, Miguel; Malats, Núria; Burns, Julie E.; Knowles, Margaret A.; Cigudosa, Juan C.; Hartmann, Arndt; Vogt, Thomas; Landthaler, Michael; Pujol, Ramón M.; Real, Francisco X.

    2010-01-01

    Malignant tumors result from the accumulation of genetic alterations in oncogenes and tumor suppressor genes. Much less is known about the genetic changes in benign tumors. Seborrheic keratoses (SK) are very frequent benign human epidermal tumors without malignant potential. We performed a comprehensive mutational screen of genes in the FGFR3-RAS-MAPK and phosphoinositide 3-kinase (PI3K)-AKT pathways from 175 SK, including multiple lesions from each patient. SK commonly harbored multiple bona fide oncogenic mutations in FGFR3, PIK3CA, KRAS, HRAS, EGFR, and AKT1 oncogenes but not in tumor suppressor genes TSC1 and PTEN. Despite the occurrence of oncogenic mutations and the evidence for downstream ERK/MAPK and PI3K pathway signaling, we did not find induction of senescence or a DNA damage response. Array comparative genomic hybridization (aCGH) analysis revealed that SK are genetically stable. The pattern of oncogenic mutations and X chromosome inactivation departs significantly from randomness and indicates that spatially independent lesions from a given patient share a clonal relationship. Our findings show that multiple oncogenic mutations in the major signaling pathways involved in cancer are not sufficient to drive malignant tumor progression. Furthermore, our data provide clues on the origin and spread of oncogenic mutations in tissues, suggesting that apparently independent (multicentric) adult benign tumors may have a clonal origin. PMID:21078999

  17. In situ Expression of Functional Genes Reveals Nitrogen Cycling at High Temperatures in Terrestrial Hydrothermal Systems

    NASA Astrophysics Data System (ADS)

    Loiacono, S. T.; Meyer-Dombard, D. R.

    2011-12-01

    An essential element for life, nitrogen occurs in all living organisms and is critical for the synthesis of amino acids, proteins, nucleic acids, and other forms of biomass. Thus, nitrogen cycling likely plays a vital role in microbial metabolic processes as well as nutrient availability. For microorganisms in "extreme" environments, this means developing adaptations that allow them to survive in harsh conditions and still perform the metabolisms essential to sustain life. Recent studies have screened biofilms and thermal sediments of Yellowstone National Park (YNP) thermal features for the presence of nifH genes, which code for a key enzyme in the nitrogen fixation process [1-4]. Furthermore, analysis of nitrogen isotopes in biofilms across a temperature and chemical gradient revealed that nitrogen fixation likely varies across the chemosynthetic/photosynthetic ecotone [5]. Although research has evaluated and confirmed the presence of nifH genes in various thermophilic microbial communities, the existence of a gene in the DNA of an organism does not verify its use. Instead, other methods, such as culturing, isotope tracer assays, and gene expression studies are required to provide direct evidence of biological nitrogen fixation. Culturing and isotope tracer approaches have successfully revealed high-temperature biological nitrogen fixation in both marine hydrothermal vent microbial communities [6] and in acidic, terrestrial hydrothermal sediment [3]. Transcriptomics-based techniques (using mRNA extracted from samples to confirm in situ expression of targeted genes) have been much more limited in number, and only a few studies have, to date, investigated in situ expression of the nifH gene in thermophilic microbial communities [2, 7]. This study explores the presence and expression of nifH genes in several features of the Lower Geyser Basin (LGB) of YNP. Nucleic acids from chemosynthetic and photosynthetic microbial communities were extracted and then amplified

  18. Oncogenic role of KIAA0101 interacting with proliferating cell nuclear antigen in pancreatic cancer.

    PubMed

    Hosokawa, Masayo; Takehara, Akio; Matsuda, Koichi; Eguchi, Hidetoshi; Ohigashi, Hiroaki; Ishikawa, Osamu; Shinomura, Yasuhisa; Imai, Kohzoh; Nakamura, Yusuke; Nakagawa, Hidewaki

    2007-03-15

    To isolate novel diagnostic markers and therapeutic targets for pancreatic cancer, we earlier did expression profile analysis of pancreatic cancer cells using a genome-wide cDNA microarray combined with microdissection. Among dozens of trans-activated genes in pancreatic cancer cells, this study focused on KIAA0101 whose overexpression in pancreatic cancer cells was validated by immunohistochemical analysis. KIAA0101 was previously identified as p15(PAF) [proliferating cell nuclear antigen (PCNA)-associated factor] to bind with PCNA; however, its function remains unknown. To investigate for the biological significance of KIAA0101 overexpression in cancer cells, we knocked down KIAA0101 by small interfering RNA (siRNA) in pancreatic cancer cells and found that the reduced expression by siRNA caused drastic attenuation of their proliferation as well as significant decrease in DNA replication rate. Concordantly, exogenous overexpression of KIAA0101 enhanced cancer cell growth, and NIH3T3 derivative cells expressing KIAA0101 revealed in vivo tumor formation, implying its growth-promoting and oncogenic property. We also showed that the expression of KIAA0101 was regulated tightly by the p53-p21 pathway. To consider the KIAA0101/PCNA interaction as a therapeutic target, we designed the cell-permeable 20-amino-acid dominant-negative peptide and found that it could effectively inhibit the KIAA0101/PCNA interaction and resulted in the significant growth suppression of cancer cells. Our results clearly implicated that suppression of the KIAA0101 and PCNA oncogenic activity, or the inhibition of KIAA0101/PCNA interaction, is likely to be a promising strategy to develop novel cancer therapeutic drugs.

  19. Mars surface diversity as revealed by the OMEGA/Mars Express observations.

    PubMed

    Bibring, Jean-Pierre; Langevin, Yves; Gendrin, Aline; Gondet, Brigitte; Poulet, François; Berthé, Michel; Soufflot, Alain; Arvidson, Ray; Mangold, Nicolas; Mustard, John; Drossart, P

    2005-03-11

    The Observatoire pour la Minéralogie, l'Eau, les Glaces, et l'Activité (OMEGA) investigation, on board the European Space Agency Mars Express mission, is mapping the surface composition of Mars at a 0.3- to 5-kilometer resolution by means of visible-near-infrared hyperspectral reflectance imagery. The data acquired during the first 9 months of the mission already reveal a diverse and complex surface mineralogy, offering key insights into the evolution of Mars. OMEGA has identified and mapped mafic iron-bearing silicates of both the northern and southern crust, localized concentrations of hydrated phyllosilicates and sulfates but no carbonates, and ices and frosts with a water-ice composition of the north polar perennial cap, as for the south cap, covered by a thin carbon dioxide-ice veneer.

  20. Spaceflight Alters Bacterial Gene Expression and Virulence and Reveals Role for Global Regulator Hfq

    NASA Technical Reports Server (NTRS)

    Wilson, J. W.; Ott, C. M.; zuBentrup, K. Honer; Ramamurthy R.; Quick, L.; Porwollik, S.; Cheng, P.; McClellan, M.; Tsaprailis, G.; Radabaugh, T.; Hunt, A.; Fernandez, D.; Richter, E.; Shah, M.; Kilcoyne, M.; Joshi, L.; Nelman-Gonzalez, M.; Hing, S.; Parra, M.; Dumaras, P.; Norwood, K.; Nickerson, C. A.; Bober, R.; Devich, J.; Ruggles, A.

    2007-01-01

    A comprehensive analysis of both the molecular genetic and phenotypic responses of any organism to the spaceflight environment has never been accomplished due to significant technological and logistical hurdles. Moreover, the effects of spaceflight on microbial pathogenicity and associated infectious disease risks have not been studied. The bacterial pathogen Salmonella typhimurium was grown aboard Space Shuttle mission STS-115 and compared to identical ground control cultures. Global microarray and proteomic analyses revealed 167 transcripts and 73 proteins changed expression with the conserved RNA-binding protein Hfq identified as a likely global regulator involved in the response to this environment. Hfq involvement was confirmed with a ground based microgravity culture model. Spaceflight samples exhibited enhanced virulence in a murine infection model and extracellular matrix accumulation consistent with a biofilm. Strategies to target Hfq and related regulators could potentially decrease infectious disease risks during spaceflight missions and provide novel therapeutic options on Earth.

  1. The chemodiversity of wines can reveal a metabologeography expression of cooperage oak wood

    PubMed Central

    Gougeon, Régis D.; Lucio, Marianna; Frommberger, Moritz; Peyron, Dominique; Chassagne, David; Alexandre, Hervé; Feuillat, François; Voilley, Andrée; Cayot, Philippe; Gebefügi, Istvan; Hertkorn, Norbert; Schmitt-Kopplin, Philippe

    2009-01-01

    Wine chemical compositions, which result from a complex interplay between environmental factors, genetic factors, and viticultural practices, have mostly been studied using targeted analyses of selected families of metabolites. Detailed studies have particularly concerned volatile and polyphenolic compounds because of their acknowledged roles in the organoleptic and therapeutic properties. However, we show that an unprecedented chemical diversity of wine composition can be unraveled through a nontargeted approach by ultrahigh-resolution mass spectrometry, which provides an instantaneous image of complex interacting processes, not easily or possibly resolvable into their unambiguous individual contributions. In particular, the statistical analysis of a series of barrel-aged wines revealed that 10-year-old wines still express a metabologeographic signature of the forest location where oaks of the barrel in which they were aged have grown. PMID:19470460

  2. Meta-Analysis of Gene Expression Profiles in Acute Promyelocytic Leukemia Reveals Involved Pathways

    PubMed Central

    Jalili, Mahdi; Salehzadeh-Yazdi, Ali; Mohammadi, Saeed; Yaghmaie, Marjan; Ghavamzadeh, Ardeshir; Alimoghaddam, Kamran

    2017-01-01

    Background: Acute promyelocytic leukemia (APL) is a unique subtype of acute leukemia. APL is a curable disease; however, drug resistance, early mortality, disease relapse and treatment-related complications remain challenges in APL patient management. One issue underlying these challenges is that the molecular mechanisms of the disease are not sufficiently understood. Materials and Methods: In this study, we performed a meta-analysis of gene expression profiles derived from microarray experiments and explored the background of disease by functional and pathway analysis. Results: Our analysis revealed a gene signature with 406 genes that are up or down-regulated in APL. The pathway analysis determined that MAPK pathway and its involved elements such as JUN gene and AP-1 play important roles in APL pathogenesis along with insulin-like growth factor–binding protein-7. Conclusion: The results of this meta-analysis could be useful for developing more effective therapy strategies and new targets for diagnosis and drugs. PMID:28286608

  3. The crystal structure of the DNA-binding domain of vIRF-1 from the oncogenic KSHV reveals a conserved fold for DNA binding and reinforces its role as a transcription factor

    PubMed Central

    Hew, Kelly; Venkatachalam, Rajakannan; Nasertorabi, Fariborz; Lim, Bee Ting; Cornvik, Tobias; Nordlund, Pär

    2013-01-01

    Kaposi’s sarcoma-associated herpesvirus encodes four viral homologues to cellular interferon regulatory factors (IRFs), where the most studied is vIRF-1. Even though vIRF-1 shows sequence homology to the N-terminal DNA-binding domain (DBD) of human IRFs, a specific role for this domain in vIRF-1’s function has remained uncertain. To provide insights into the function of the vIRF-1 DBD, we have determined the crystal structure of it in complex with DNA and in its apo-form. Using a thermal stability shift assay (TSSA), we show that the vIRF-1 DBD binds DNA, whereas full-length vIRF-1 does not, suggesting a cis-acting regulatory mechanism in similarity to human IRFs. The complex structure of vIRF-1 DBD reveals interactions with the DNA backbone and the positioning of two arginines for specific recognition in the major grove. A superimposition with human IRF-3 reveals a similar positioning of the two specificity-determining arginines, and additional TSSAs indicate binding of vIRF-1 to an IRF-3 operator consensus sequence. The results from this study, therefore, provide support that vIRF-1 has evolved to bind DNA and plays a role in DNA binding in the context of transcriptional regulation and might act on some of the many operator sequences controlled by human IRF-3. PMID:23435230

  4. The DNA rearrangement that generates the TRK-T3 oncogene involves a novel gene on chromosome 3 whose product has a potential coiled-coil domain.

    PubMed Central

    Greco, A; Mariani, C; Miranda, C; Lupas, A; Pagliardini, S; Pomati, M; Pierotti, M A

    1995-01-01

    Oncogenic rearrangements of the NTRK1 gene (also designated TRKA), encoding one of the receptors for the nerve growth factor, are frequently detected in thyroid carcinomas. Such rearrangements fuse the NTRK1 tyrosine kinase domain to 5'-end sequences belonging to different genes. In previously reported studies we have demonstrated that NTRK1 oncogenic activation involves two genes, TPM3 and TPR, both localized similarly to the receptor tyrosine kinase, on the q arm of chromosome 1. Here we report the characterization of a novel NTRK1-derived thyroid oncogene, named TRK-T3. A cDNA clone, capable of transforming activity, was isolated from a transformant cell line. Sequence analysis revealed that TRK-T3 contains 1,412 nucleotides of NTRK1 preceded by 598 nucleotides belonging to a novel gene that we have named TFG (TRK-fused gene). The TRK-T3 amino acid sequence displays, within the TFG region, a coiled-coil motif that could endow the oncoprotein with the capability to form complexes. The TRK-T3 oncogene encodes a 68-kDa cytoplasmic protein reacting with NTRK1-specific antibodies. By sedimentation gradient experiments the TRK-T3 oncoprotein was shown to form, in vivo, multimeric complexes, most likely trimers or tetramers. The TFG gene is ubiquitously expressed and is located on chromosome 3. The breakpoint producing the TRK-T3 oncogene occurs within exons of both the TFG gene and the NTRK1 gene and produces a chimeric exon that undergoes alternative splicing. Molecular analysis of the NTRK1 rearranged fragments indicated that the chromosomal rearrangement is reciprocal and balanced and involves loss of a few nucleotides of germ line sequences. PMID:7565764

  5. Differential Gene Expression Reveals Candidate Genes for Drought Stress Response in Abies alba (Pinaceae).

    PubMed

    Behringer, David; Zimmermann, Heike; Ziegenhagen, Birgit; Liepelt, Sascha

    2015-01-01

    Increasing drought periods as a result of global climate change pose a threat to many tree species by possibly outpacing their adaptive capabilities. Revealing the genetic basis of drought stress response is therefore implemental for future conservation strategies and risk assessment. Access to informative genomic regions is however challenging, especially for conifers, partially due to their large genomes, which puts constraints on the feasibility of whole genome scans. Candidate genes offer a valuable tool to reduce the complexity of the analysis and the amount of sequencing work and costs. For this study we combined an improved drought stress phenotyping of needles via a novel terahertz water monitoring technique with Massive Analysis of cDNA Ends to identify candidate genes for drought stress response in European silver fir (Abies alba Mill.). A pooled cDNA library was constructed from the cotyledons of six drought stressed and six well-watered silver fir seedlings, respectively. Differential expression analyses of these libraries revealed 296 candidate genes for drought stress response in silver fir (247 up- and 49 down-regulated) of which a subset was validated by RT-qPCR of the twelve individual cotyledons. A majority of these genes code for currently uncharacterized proteins and hint on new genomic resources to be explored in conifers. Furthermore, we could show that some traditional reference genes from model plant species (GAPDH and eIF4A2) are not suitable for differential analysis and we propose a new reference gene, TPC1, for drought stress expression profiling in needles of conifer seedlings.

  6. Differential Gene Expression Reveals Candidate Genes for Drought Stress Response in Abies alba (Pinaceae)

    PubMed Central

    Ziegenhagen, Birgit; Liepelt, Sascha

    2015-01-01

    Increasing drought periods as a result of global climate change pose a threat to many tree species by possibly outpacing their adaptive capabilities. Revealing the genetic basis of drought stress response is therefore implemental for future conservation strategies and risk assessment. Access to informative genomic regions is however challenging, especially for conifers, partially due to their large genomes, which puts constraints on the feasibility of whole genome scans. Candidate genes offer a valuable tool to reduce the complexity of the analysis and the amount of sequencing work and costs. For this study we combined an improved drought stress phenotyping of needles via a novel terahertz water monitoring technique with Massive Analysis of cDNA Ends to identify candidate genes for drought stress response in European silver fir (Abies alba Mill.). A pooled cDNA library was constructed from the cotyledons of six drought stressed and six well-watered silver fir seedlings, respectively. Differential expression analyses of these libraries revealed 296 candidate genes for drought stress response in silver fir (247 up- and 49 down-regulated) of which a subset was validated by RT-qPCR of the twelve individual cotyledons. A majority of these genes code for currently uncharacterized proteins and hint on new genomic resources to be explored in conifers. Furthermore, we could show that some traditional reference genes from model plant species (GAPDH and eIF4A2) are not suitable for differential analysis and we propose a new reference gene, TPC1, for drought stress expression profiling in needles of conifer seedlings. PMID:25924061

  7. Pharmacological strategies to target oncogenic KRAS signaling in pancreatic cancer.

    PubMed

    Chuang, Hsiao-Ching; Huang, Po-Hsien; Kulp, Samuel K; Chen, Ching-Shih

    2017-03-01

    The clear importance of mutated KRAS as a therapeutic target has driven the investigation of multiple approaches to inhibit oncogenic KRAS signaling at different molecular levels. However, no KRAS-targeted therapy has reached the clinic to date, which underlies the intrinsic difficulty in developing effective, direct inhibitors of KRAS. Thus, this article provides an overview of the history and recent progress in the development of pharmacological strategies to target oncogenic KRAS with small molecule agents. Mechanistically, these KRAS-targeted agents can be classified into the following four categories. (1) Small-molecule RAS-binding ligands that prevent RAS activation by binding within or outside the nucleotide-binding motif. (2) Inhibitors of KRAS membrane anchorage. (3) Inhibitors that bind to RAS-binding domains of RAS-effector proteins. (4) Inhibitors of KRAS expression. The advantage and limitation of each type of these anti-KRAS agents are discussed.

  8. SUMOylated IRF-1 shows oncogenic potential by mimicking IRF-2

    SciTech Connect

    Park, Sun-Mi; Chae, Myounghee; Kim, Bo-Kyoung; Seo, Taegun; Jang, Ik-Soon; Choi, Jong-Soon; Kim, Il-Chul; Lee, Je-Ho; Park, Junsoo

    2010-01-01

    Interferon regulatory factor-1 (IRF-1) is an interferon-induced transcriptional activator that suppresses tumors by impeding cell proliferation. Recently, we demonstrated that the level of SUMOylated IRF-1 is elevated in tumor cells, and that SUMOylation of IRF-1 attenuates its tumor-suppressive function. Here we report that SUMOylated IRF-1 mimics IRF-2, an antagonistic repressor, and shows oncogenic potential. To demonstrate the role of SUMOylated IRF-1 in tumorigenesis, we used SUMO-IRF-1 recombinant protein. Stable expression of SUMO-IRF-1 in NIH3T3 cells resulted in focus formation and anchorage-independent growth in soft agar. Inoculation of SUMO-IRF-1-transfected cells into athymic nude mice resulted in tumor formation and infiltration of adipose tissues. Finally, we demonstrated that SUMO-IRF-1 transforms NIH3T3 cells in a dose-dependent manner suggesting that SUMOylated IRF-1 may act as an oncogenic protein in tumor cells.

  9. Spectral sensitivity in Onychophora (velvet worms) revealed by electroretinograms, phototactic behaviour and opsin gene expression.

    PubMed

    Beckmann, Holger; Hering, Lars; Henze, Miriam J; Kelber, Almut; Stevenson, Paul A; Mayer, Georg

    2015-03-01

    Onychophorans typically possess a pair of simple eyes, inherited from the last common ancestor of Panarthropoda (Onychophora+Tardigrada+Arthropoda). These visual organs are thought to be homologous to the arthropod median ocelli, whereas the compound eyes probably evolved in the arthropod lineage. To gain insights into the ancestral function and evolution of the visual system in panarthropods, we investigated phototactic behaviour, opsin gene expression and the spectral sensitivity of the eyes in two representative species of Onychophora: Euperipatoides rowelli (Peripatopsidae) and Principapillatus hitoyensis (Peripatidae). Our behavioural analyses, in conjunction with previous data, demonstrate that both species exhibit photonegative responses to wavelengths ranging from ultraviolet to green light (370-530 nm), and electroretinograms reveal that the onychophoran eye is maximally sensitive to blue light (peak sensitivity ∼480 nm). Template fits to these sensitivities suggest that the onychophoran eye is monochromatic. To clarify which type of opsin the single visual pigment is based on, we localised the corresponding mRNA in the onychophoran eye and brain using in situ hybridization. Our data show that the r-opsin gene (onychopsin) is expressed exclusively in the photoreceptor cells of the eye, whereas c-opsin mRNA is confined to the optic ganglion cells and the brain. Together, our findings suggest that the onychopsin is involved in vision, whereas c-opsin might have a photoreceptive, non-visual function in onychophorans.

  10. Comparative Transcriptome Analysis Reveals Early Pregnancy-Specific Genes Expressed in Peripheral Blood of Pregnant Sows

    PubMed Central

    Zhu, Shien; Shi, Wenqing; Hu, Maishun; Fu, Xiangwei; Wang, Chuduan; Wang, Yachun; Zhang, Qin; Yu, Ying

    2014-01-01

    Early and accurate diagnosis of pregnancy is important for effective management of an economical pig farm. Besides the currently available methods used in early diagnosis of sows, circulating nucleic acids in peripheral blood may contain some early pregnancy-specific molecular markers. For the first time, microarray analysis of peripheral blood from pregnant sows versus non-pregnant sows identified 127 up-regulated and 56 down-regulated genes at day 14 post-insemination. Gene Ontology annotation grouped the total differently expressed genes into 3 significantly enriched terms, cell surface receptor linked signal transduction, G-protein coupled receptor protein signaling pathway and regulation of vesicle-mediated transport. Signaling pathway analysis revealed the only one significantly changed pathway was arachidonic acid metabolism. Of the differently expressed genes, nine (including LPAR3, RXFP4, GALP, CBR1, CBR2, GPX6, USP18, LHB and NR5A1) were found to exert function related to early pregnancy processes. This study provides a clue that differentially abundant RNAs in maternal peripheral blood can help to identify the molecular markers of early pregnancy in pigs. PMID:25479131

  11. Dietary switch reveals fast coordinated gene expression changes in Drosophila melanogaster

    PubMed Central

    Ding, Feifei; Tatar, Marc; Helfand, Stephen L.; Neretti, Nicola

    2014-01-01

    Dietary restriction (DR) reduces age-specific mortality and increases lifespan in many organisms. DR elicits a large number of physiological changes, however many are undoubtedly not related to longevity. Whole-genome gene expression studies have typically revealed hundreds to thousands of differentially expressed genes in response to DR, and a key open question is which subset of genes mediates longevity. Here we performed transcriptional profiling of fruit flies in a closely spaced time series immediately following a switch to the DR regime and identified four patterns of transcriptional dynamics. Most informatively we find 144 genes rapidly switched to the same level observed in the DR cohort and are hence strong candidates as proximal mediators of reduced mortality upon DR. This class was enriched for genes involved in carbohydrate and fatty acid metabolism. Folate biosynthesis was the only pathway enriched for gene up-regulated upon DR. Four among the down-regulated genes are involved in key regulatory steps within the pentose phosphate pathway, which has been previously associated with lifespan extension in Drosophila. Combined analysis of dietary switch with whole-genome time-course profiling can identify transcriptional responses that are closely associated with and perhaps causal to longevity assurance conferred by dietary restriction. PMID:24864304

  12. Expression of secreted Wnt pathway components reveals unexpected complexity of the planarian amputation response.

    PubMed

    Gurley, Kyle A; Elliott, Sarah A; Simakov, Oleg; Schmidt, Heiko A; Holstein, Thomas W; Sánchez Alvarado, Alejandro

    2010-11-01

    Regeneration is widespread throughout the animal kingdom, but our molecular understanding of this process in adult animals remains poorly understood. Wnt/β-catenin signaling plays crucial roles throughout animal life from early development to adulthood. In intact and regenerating planarians, the regulation of Wnt/β-catenin signaling functions to maintain and specify anterior/posterior (A/P) identity. Here, we explore the expression kinetics and RNAi phenotypes for secreted members of the Wnt signaling pathway in the planarian Schmidtea mediterranea. Smed-wnt and sFRP expression during regeneration is surprisingly dynamic and reveals fundamental aspects of planarian biology that have been previously unappreciated. We show that after amputation, a wounding response precedes rapid re-organization of the A/P axis. Furthermore, cells throughout the body plan can mount this response and reassess their new A/P location in the complete absence of stem cells. While initial stages of the amputation response are stem cell independent, tissue remodeling and the integration of a new A/P address with anatomy are stem cell dependent. We also show that WNT5 functions in a reciprocal manner with SLIT to pattern the planarian mediolateral axis, while WNT11-2 patterns the posterior midline. Moreover, we perform an extensive phylogenetic analysis on the Smed-wnt genes using a method that combines and integrates both sequence and structural alignments, enabling us to place all nine genes into Wnt subfamilies for the first time.

  13. Global absolute quantification reveals tight regulation of protein expression in single Xenopus eggs

    PubMed Central

    Smits, Arne H.; Lindeboom, Rik G.H.; Perino, Matteo; van Heeringen, Simon J.; Veenstra, Gert Jan C.; Vermeulen, Michiel

    2014-01-01

    While recent developments in genomic sequencing technology have enabled comprehensive transcriptome analyses of single cells, single cell proteomics has thus far been restricted to targeted studies. Here, we perform global absolute protein quantification of fertilized Xenopus laevis eggs using mass spectrometry-based proteomics, quantifying over 5800 proteins in the largest single cell proteome characterized to date. Absolute protein amounts in single eggs are highly consistent, thus indicating a tight regulation of global protein abundance. Protein copy numbers in single eggs range from tens of thousands to ten trillion copies per cell. Comparison between the single-cell proteome and transcriptome reveal poor expression correlation. Finally, we identify 439 proteins that significantly change in abundance during early embryogenesis. Downregulated proteins include ribosomal proteins and upregulated proteins include basal transcription factors, among others. Many of these proteins do not show regulation at the transcript level. Altogether, our data reveal that the transcriptome is a poor indicator of the proteome and that protein levels are tightly controlled in X. laevis eggs. PMID:25056316

  14. Global absolute quantification reveals tight regulation of protein expression in single Xenopus eggs.

    PubMed

    Smits, Arne H; Lindeboom, Rik G H; Perino, Matteo; van Heeringen, Simon J; Veenstra, Gert Jan C; Vermeulen, Michiel

    2014-09-01

    While recent developments in genomic sequencing technology have enabled comprehensive transcriptome analyses of single cells, single cell proteomics has thus far been restricted to targeted studies. Here, we perform global absolute protein quantification of fertilized Xenopus laevis eggs using mass spectrometry-based proteomics, quantifying over 5800 proteins in the largest single cell proteome characterized to date. Absolute protein amounts in single eggs are highly consistent, thus indicating a tight regulation of global protein abundance. Protein copy numbers in single eggs range from tens of thousands to ten trillion copies per cell. Comparison between the single-cell proteome and transcriptome reveal poor expression correlation. Finally, we identify 439 proteins that significantly change in abundance during early embryogenesis. Downregulated proteins include ribosomal proteins and upregulated proteins include basal transcription factors, among others. Many of these proteins do not show regulation at the transcript level. Altogether, our data reveal that the transcriptome is a poor indicator of the proteome and that protein levels are tightly controlled in X. laevis eggs.

  15. Genome-Wide Expression Profiling Reveals S100B as Biomarker for Invasive Aspergillosis

    PubMed Central

    Dix, Andreas; Czakai, Kristin; Springer, Jan; Fliesser, Mirjam; Bonin, Michael; Guthke, Reinhard; Schmitt, Anna L.; Einsele, Hermann; Linde, Jörg; Löffler, Jürgen

    2016-01-01

    Invasive aspergillosis (IA) is a devastating opportunistic infection and its treatment constitutes a considerable burden for the health care system. Immunocompromised patients are at an increased risk for IA, which is mainly caused by the species Aspergillus fumigatus. An early and reliable diagnosis is required to initiate the appropriate antifungal therapy. However, diagnostic sensitivity and accuracy still needs to be improved, which can be achieved at least partly by the definition of new biomarkers. Besides the direct detection of the pathogen by the current diagnostic methods, the analysis of the host response is a promising strategy toward this aim. Following this approach, we sought to identify new biomarkers for IA. For this purpose, we analyzed gene expression profiles of hematological patients and compared profiles of patients suffering from IA with non-IA patients. Based on microarray data, we applied a comprehensive feature selection using a random forest classifier. We identified the transcript coding for the S100 calcium-binding protein B (S100B) as a potential new biomarker for the diagnosis of IA. Considering the expression of this gene, we were able to classify samples from patients with IA with 82.3% sensitivity and 74.6% specificity. Moreover, we validated the expression of S100B in a real-time reverse transcription polymerase chain reaction (RT-PCR) assay and we also found a down-regulation of S100B in A. fumigatus stimulated DCs. An influence on the IL1B and CXCL1 downstream levels was demonstrated by this S100B knockdown. In conclusion, this study covers an effective feature selection revealing a key regulator of the human immune response during IA. S100B may represent an additional diagnostic marker that in combination with the established techniques may improve the accuracy of IA diagnosis. PMID:27047454

  16. Comprehensive Gene Expression Profiling Reveals Synergistic Functional Networks in Cerebral Vessels after Hypertension or Hypercholesterolemia

    PubMed Central

    Ong, Wei-Yi; Ng, Mary Pei-Ern; Loke, Sau-Yeen; Jin, Shalai; Wu, Ya-Jun; Tanaka, Kazuhiro; Wong, Peter Tsun-Hon

    2013-01-01

    Atherosclerotic stenosis of cerebral arteries or intracranial large artery disease (ICLAD) is a major cause of stroke especially in Asians, Hispanics and Africans, but relatively little is known about gene expression changes in vessels at risk. This study compares comprehensive gene expression profiles in the middle cerebral artery (MCA) of New Zealand White rabbits exposed to two stroke risk factors i.e. hypertension and/or hypercholesterolemia, by the 2-Kidney-1-Clip method, or dietary supplementation with cholesterol. Microarray and Ingenuity Pathway Analyses of the MCA of the hypertensive rabbits showed up-regulated genes in networks containing the node molecules: UBC (ubiquitin), P38 MAPK, ERK, NFkB, SERPINB2, MMP1 and APP (amyloid precursor protein); and down-regulated genes related to MAPK, ERK 1/2, Akt, 26 s proteasome, histone H3 and UBC. The MCA of hypercholesterolemic rabbits showed differentially expressed genes that are surprisingly, linked to almost the same node molecules as the hypertensive rabbits, despite a relatively low percentage of ‘common genes’ (21 and 7%) between the two conditions. Up-regulated common genes were related to: UBC, SERPINB2, TNF, HNF4A (hepatocyte nuclear factor 4A) and APP, and down-regulated genes, related to UBC. Increased HNF4A message and protein were verified in the aorta. Together, these findings reveal similar nodal molecules and gene pathways in cerebral vessels affected by hypertension or hypercholesterolemia, which could be a basis for synergistic action of risk factors in the pathogenesis of ICLAD. PMID:23874591

  17. Genetic disruption of oncogenic Kras sensitizes lung cancer cells to Fas receptor-mediated apoptosis.

    PubMed

    Mou, Haiwei; Moore, Jill; Malonia, Sunil K; Li, Yingxiang; Ozata, Deniz M; Hough, Soren; Song, Chun-Qing; Smith, Jordan L; Fischer, Andrew; Weng, Zhiping; Green, Michael R; Xue, Wen

    2017-04-04

    Genetic lesions that activate KRAS account for ∼30% of the 1.6 million annual cases of lung cancer. Despite clinical need, KRAS is still undruggable using traditional small-molecule drugs/inhibitors. When oncogenic Kras is suppressed by RNA interference, tumors initially regress but eventually recur and proliferate despite suppression of Kras Here, we show that tumor cells can survive knockout of oncogenic Kras, indicating the existence of Kras-independent survival pathways. Thus, even if clinical KRAS inhibitors were available, resistance would remain an obstacle to treatment. Kras-independent cancer cells exhibit decreased colony formation in vitro but retain the ability to form tumors in mice. Comparing the transcriptomes of oncogenic Kras cells and Kras knockout cells, we identified 603 genes that were specifically up-regulated in Kras knockout cells, including the Fas gene, which encodes a cell surface death receptor involved in physiological regulation of apoptosis. Antibodies recognizing Fas receptor efficiently induced apoptosis of Kras knockout cells but not oncogenic Kras-expressing cells. Increased Fas expression in Kras knockout cells was attributed to decreased association of repressive epigenetic marks at the Fas promoter. Concordant with this observation, treating oncogenic Kras cells with histone deacetylase inhibitor and Fas-activating antibody efficiently induced apoptosis, thus bypassing the need to inhibit Kras. Our results suggest that activation of Fas could be exploited as an Achilles' heel in tumors initiated by oncogenic Kras.

  18. Oncogenic signals of HER-2/neu in regulating the stability of the cyclin-dependent kinase inhibitor p27.

    PubMed

    Yang, H Y; Zhou, B P; Hung, M C; Lee, M H

    2000-08-11

    Overexpression and activation of HER-2/neu, a proto-oncogene, play a pivotal role in cancer formation. Strong expression of HER-2/neu in cancers has been associated with poor prognosis. Reduced expression of p27(Kip1), a cyclin-dependent kinase inhibitor, correlates with poor clinical outcome in many types of carcinomas. Because many cancers with the overexpression of HER-2/neu overlap with those affected by reduced p27 expression, we studied the link between HER-2/neu oncogenic signals and p27 regulation. We found that down-regulation of p27 correlates with HER-2/neu overexpression. To address the molecular mechanism of this inverse correlation, we found that reduction of p27 is caused by enhanced ubiquitin-mediated degradation, and the HER-2/Grb2/MAPK pathway is involved in the decrease of p27 stability. Also, HER-2/neu activity causes mislocation of p27 and Jun activation domain-binding protein 1 (JAB1), an exporter of p27, into the cytoplasm, thereby facilitating p27 degradation. These results reveal that HER-2/neu signals reduce p27 stability and thus present potential points for therapeutic intervention in HER-2/neu-associated cancers.

  19. MiR-205 functions as a tumor suppressor in adenocarcinoma and an oncogene in squamous cell carcinoma of esophagus.

    PubMed

    Hezova, Renata; Kovarikova, Alena; Srovnal, Josef; Zemanova, Milada; Harustiak, Tomas; Ehrmann, Jiri; Hajduch, Marian; Sachlova, Milana; Svoboda, Marek; Slaby, Ondrej

    2016-06-01

    Esophageal cancer is a malignant disease with poor prognosis, increasing incidence, and ineffective treatment options. MicroRNAs are post-transcriptional regulators of gene expression involved in many biological processes including carcinogenesis. We determined miR-205 expression levels in tumor/non-tumor tissues of 45 esophageal cancer patients using qPCR and found that decreased level of miR-205 in tumor tissue correlates with poor overall survival in esophageal adenocarcinoma patients. Further, we observed significantly higher levels of miR-205 in tumor tissue of esophageal squamous cell carcinoma. Ectopic overexpression of miR-205 in adenocarcinoma cell line SK-GT-4 led to decreased cell proliferation, cell cycle arrest in G1, and decreased migration ability. Conversely, in squamous cell line KYSE-150, same effects like inhibition of proliferation, migration, and colony-forming potential and cell cycle arrest in G2 were observed after silencing of miR-205. We performed global gene expression profiling and revealed that suppressive functioning of miR-205 in adenocarcinoma could be realized through regulation of epithelial-mesenchymal transition (EMT), whereas oncogenic in squamous cell carcinoma by regulation of metalloproteinase 10. Our results suggest that miR-205 could serve as biomarker in esophageal cancer and acts as a tumor suppressor in esophageal adenocarcinoma and oncogene in esophageal squamous cell carcinoma.

  20. Oncogene addiction: sometimes a temporary slavery.

    PubMed

    Jonkers, Jos; Berns, Anton

    2004-12-01

    Tumors induced in conditional oncomice can show remarkable different responses to subsequent oncogene deprivation. Complete sustained regression, concomitant with massive differentiation and/or apoptosis, and partial regression are both observed. In the latter case, tumor growth either resumes without being dependent any longer on the oncogene, or requires reactivation of the oncogene in cells that have become dormant. These models reflect many of the features we also witness in human cancer and can therefore assist us in understanding the underlying mechanisms and in designing more effective treatment protocols.

  1. Interferon-Tau has Antiproliferative effects, Represses the Expression of E6 and E7 Oncogenes, Induces Apoptosis in Cell Lines Transformed with HPV16 and Inhibits Tumor Growth In Vivo

    PubMed Central

    Padilla-Quirarte, Herbey Oswaldo; Trejo-Moreno, Cesar; Fierros-Zarate, Geny; Castañeda, Jhoseline Carnalla; Palma-Irizarry, Marie; Hernández-Márquez, Eva; Burguete-Garcia, Ana Isabel; Peralta-Zaragoza, Oscar; Madrid-Marina, Vicente; Torres-Poveda, Kirvis; Bermúdez-Morales, Victor Hugo

    2016-01-01

    Interferon tau (IFN-τ) is a promising alternative antiviral and immunotherapeutic agent in a wide variety of diseases including infectious, neurodegenerative, autoimmune and cancer due to its low toxicity in comparison with other type I interferon´s. The objective of our study was established the effect of the bovine IFN-τ on human (SiHa) and murine (BMK-16/myc) cells transformed with HPV 16 and evaluates the antitumor effect in a murine tumor model HPV 16 positive. We determine that bovine IFN-τ has antiproliferative effects, pro-apoptotic activity and induces repression of viral E6 and E7 oncogenes (time- and dose-dependent) on human and murine cells transformed with HPV 16 similar to the effects of IFN-β. However, IFN-τ induces greater antiproliferative effect, apoptosis and repression of both oncogenes in BMK-16/myc cells compared to SiHa cells. The differences were explained by the presence and abundance of the type I interferon receptor (IFNAR) in each cell line. On the other hand, we treated groups of tumor-bearing mice (HPV16 positive) with IFN-τ and showed the inhibition tumor growth effect in vivo. Our finding indicates that bovine IFN-τ may be a good candidate for immunotherapy against cervical cancer. PMID:27994659

  2. Sensitizers, protectors and oncogenic transformation in vitro

    SciTech Connect

    Miller, R.C.; Osmak, R.; Zimmerman, M.; Hall, E.J.

    1982-03-01

    Systems developed to assay oncogenic transformation in vitro represent a rapid and powerful tool to screen and compare new radiosensitizers in their carcinogenic potential, and to search for compounds that reduce or inhibit carcinogenesis produced by both radiation and sensitizers. An established line of mouse embryo fibroblasts (C3H/10T1/2 cells) has been used to determine the incidence of transformation produced by a variety of 2 and 5 substituted nitroimidazoles; these include metronidazole, desmethylmisonidazle, misonidazole, SR 2508, SR 2555, R0-07-0741, RSU-1047 and RSU-1021. Most of these sensitizers produce a similar level of transformation; for example a three day exposure of aerated cells to a concentration of 1 mM of the drug results in a transformation incidence comparable to 1 Gy of X rays. The notable exception is SR 2508 which produces a five-fold higher incidence of transformation. The potential carcinogenicity of sensitizers must be considered in choosing which of the currently available new drugs is to be used in clinical trials as an alternative to misonidazle. Superoxide dismutase (SOD), a known free radical scavenger, has been shown to reduce the level of transformation produced by radiation and sensitizers. To be effective, SOD must be present for prolonged periods during the fixation and expression period of the transformation process.

  3. Analysis of gene expression during parabolic flights reveals distinct early gravity responses in Arabidopsis roots.

    PubMed

    Aubry-Hivet, D; Nziengui, H; Rapp, K; Oliveira, O; Paponov, I A; Li, Y; Hauslage, J; Vagt, N; Braun, M; Ditengou, F A; Dovzhenko, A; Palme, K

    2014-01-01

    Plant roots are among most intensively studied biological systems in gravity research. Altered gravity induces asymmetric cell growth leading to root bending. Differential distribution of the phytohormone auxin underlies root responses to gravity, being coordinated by auxin efflux transporters from the PIN family. The objective of this study was to compare early transcriptomic changes in roots of Arabidopsis thaliana wild type, and pin2 and pin3 mutants under parabolic flight conditions and to correlate these changes to auxin distribution. Parabolic flights allow comparison of transient 1-g, hypergravity and microgravity effects in living organisms in parallel. We found common and mutation-related genes differentially expressed in response to transient microgravity phases. Gene ontology analysis of common genes revealed lipid metabolism, response to stress factors and light categories as primarily involved in response to transient microgravity phases, suggesting that fundamental reorganisation of metabolic pathways functions upstream of a further signal mediating hormonal network. Gene expression changes in roots lacking the columella-located PIN3 were stronger than in those deprived of the epidermis and cortex cell-specific PIN2. Moreover, repetitive exposure to microgravity/hypergravity and gravity/hypergravity flight phases induced an up-regulation of auxin responsive genes in wild type and pin2 roots, but not in pin3 roots, suggesting a critical function of PIN3 in mediating auxin fluxes in response to transient microgravity phases. Our study provides important insights towards understanding signal transduction processes in transient microgravity conditions by combining for the first time the parabolic flight platform with the transcriptome analysis of different genetic mutants in the model plant, Arabidopsis.

  4. miRNA and mRNA expression analysis reveals potential sex-biased miRNA expression

    PubMed Central

    Guo, Li; Zhang, Qiang; Ma, Xiao; Wang, Jun; Liang, Tingming

    2017-01-01

    Recent studies suggest that mRNAs may be differentially expressed between males and females. This study aimed to perform expression analysis of mRNA and its main regulatory molecule, microRNA (miRNA), to discuss the potential sex-specific expression patterns using abnormal expression profiles from The Cancer Genome Atlas database. Generally, deregulated miRNAs and mRNAs had consistent expression between males and females, but some miRNAs may be oppositely expressed in specific diseases: up-regulated in one group and down-regulated in another. Studies of miRNA gene families and clusters further confirmed that these sequence or location related miRNAs might have opposing expression between sexes. The specific miRNA might have greater expression divergence across different groups, suggesting flexible expression across different individuals, especially in tumor samples. The typical analysis regardless of the sex will ignore or balance these sex-specific deregulated miRNAs. Compared with flexible miRNAs, their targets of mRNAs showed relative stable expression between males and females. These relevant results provide new insights into miRNA-mRNA interaction and sex difference. PMID:28045090

  5. Oncogenic transformation of diverse gastrointestinal tissues in primary organoid culture

    PubMed Central

    Li, Xingnan; Nadauld, Lincoln; Ootani, Akifumi; Corney, David C.; Pai, Reetesh K.; Gevaert, Olivier; Cantrell, Michael A.; Rack, Paul G.; Neal, James T.; Chan, Carol W-M.; Yeung, Trevor; Gong, Xue; Yuan, Jenny; Wilhelmy, Julie; Robine, Sylvie; Attardi, Laura D.; Plevritis, Sylvia K.; Hung, Kenneth E.; Chen, Chang-Zheng; Ji, Hanlee P.; Kuo, Calvin J.

    2014-01-01

    The application of primary organoid cultures containing epithelial and mesenchymal elements to cancer modeling holds promise for combining the accurate multilineage differentiation and physiology of in vivo systems with the facile in vitro manipulation of transformed cell lines. Here, a single air-liquid interface culture method was used without modification to engineer oncogenic mutations into primary epithelial/mesenchymal organoids from mouse colon, stomach and pancreas. Pancreatic and gastric organoids exhibited dysplasia upon KrasG12D expression and/or p53 loss, and readily generated adenocarcinoma upon in vivo transplantation. In contrast, primary colon organoids required combinatorial Apc, p53, KrasG12D and Smad4 mutations for progressive transformation to invasive adenocarcinoma-like histology in vitro and tumorigenicity in vivo, recapitulating multi-hit models of colorectal cancer (CRC), and versus more promiscuous transformation of small intestinal organoids. Colon organoid culture functionally validated the microRNA miR-483 as a dominant driver oncogene at the Insulin-like growth factor-2 (IGF2) 11p15.5 CRC amplicon, inducing dysplasia in vitro and tumorigenicity in vivo. These studies demonstrate the general utility of a highly tractable primary organoid system for cancer modeling and driver oncogene validation in diverse gastrointestinal tissues. PMID:24859528

  6. PRG3 induces Ras-dependent oncogenic cooperation in gliomas

    PubMed Central

    Yakubov, Eduard; Chen, Daishi; Broggini, Thomas; Sehm, Tina; Majernik, Gökce Hatipoglu; Hock, Stefan W.; Schwarz, Marc; Engelhorn, Tobias; Doerfler, Arnd; Buchfelder, Michael; Eyupoglu, Ilker Y.; Savaskan, Nicolai E.

    2016-01-01

    Malignant gliomas are one of the most devastating cancers in humans. One characteristic hallmark of malignant gliomas is their cellular heterogeneity with frequent genetic lesions and disturbed gene expression levels conferring selective growth advantage. Here, we report on the neuronal-associated growth promoting gene PRG3 executing oncogenic cooperation in gliomas. We have identified perturbed PRG3 levels in human malignant brain tumors displaying either elevated or down-regulated PRG3 levels compared to non-transformed specimens. Further, imbalanced PRG3 levels in gliomas foster Ras-driven oncogenic amplification with increased proliferation and cell migration although angiogenesis was unaffected. Hence, PRG3 interacts with RasGEF1 (RasGRF1/CDC25), undergoes Ras-induced challenges, whereas deletion of the C-terminal domain of PRG3 (PRG3ΔCT) inhibits Ras. Moreover PRG3 silencing makes gliomas resistant to Ras inhibition. In vivo disequilibrated PRG3 gliomas show aggravated proliferation, invasion, and deteriorate clinical outcome. Thus, our data show that the interference with PRG3 homeostasis amplifies oncogenic properties and foster the malignancy potential in gliomas. PMID:27058420

  7. CRAF R391W is a melanoma driver oncogene

    PubMed Central

    Atefi, Mohammad; Titz, Bjoern; Tsoi, Jennifer; Avramis, Earl; Le, Allison; Ng, Charles; Lomova, Anastasia; Lassen, Amanda; Friedman, Michael; Chmielowski, Bartosz; Ribas, Antoni; Graeber, Thomas G.

    2016-01-01

    Approximately 75% of melanomas have known driver oncogenic mutations in BRAF, NRAS, GNA11 or GNAQ, while the mutations providing constitutive oncogenic signaling in the remaining melanomas are not known. We established a melanoma cell line from a tumor with none of the common driver mutations. This cell line demonstrated a signaling profile similar to BRAF-mutants, but lacked sensitivity to the BRAF inhibitor vemurafenib. RNA-seq mutation data implicated CRAF R391W as the alternative driver mutation of this melanoma. CRAF R391W was homozygous and over expressed. These melanoma cells were highly sensitive to CRAF, but not BRAF knockdown. In reconstitution experiments, CRAF R391W, but not CRAF WT, transformed NIH3T3 cells in soft-agar colony formation assays, increased kinase activity in vitro, induced MAP kinase signaling and conferred vemurafenib resistance. MAP kinase inducing activity was dependent on CRAF dimerization. Thus, CRAF is a bona fide alternative oncogene for BRAF/NRAS/GNAQ/GNA11 wild type melanomas. PMID:27273450

  8. PERK Integrates Oncogenic Signaling and Cell Survival During Cancer Development.

    PubMed

    Bu, Yiwen; Diehl, J Alan

    2016-10-01

    Unfolded protein responses (UPR), consisting of three major transducers PERK, IRE1, and ATF6, occur in the midst of a variety of intracellular and extracellular challenges that perturb protein folding in the endoplasmic reticulum (ER). ER stress occurs and is thought to be a contributing factor to a number of human diseases, including cancer, neurodegenerative disorders, and various metabolic syndromes. In the context of neoplastic growth, oncogenic stress resulting from dysregulation of oncogenes such as c-Myc, Braf(V600E) , and HRAS(G12V) trigger the UPR as an adaptive strategy for cancer cell survival. PERK is an ER resident type I protein kinase harboring both pro-apoptotic and pro-survival capabilities. PERK, as a coordinator through its downstream substrates, reprograms cancer gene expression to facilitate survival in response to oncogenes and microenvironmental challenges, such as hypoxia, angiogenesis, and metastasis. Herein, we discuss how PERK kinase engages in tumor initiation, transformation, adaption microenvironmental stress, chemoresistance and potential opportunities, and potential opportunities for PERK targeted therapy. J. Cell. Physiol. 231: 2088-2096, 2016. © 2016 Wiley Periodicals, Inc.

  9. Transcriptome Analysis Reveals Regulation of Gene Expression for Lipid Catabolism in Young Broilers by Butyrate Glycerides

    PubMed Central

    Yin, Fugui; Yu, Hai; Lepp, Dion; Shi, Xuejiang; Yang, Xiaojian; Hu, Jielun; Leeson, Steve; Yang, Chengbo; Nie, Shaoping; Hou, Yongqing; Gong, Joshua

    2016-01-01

    indicated that dietary BG intervention induced 79 and 205 characterized DEGs in the jejunum and liver, respectively. In addition, 255 and 165 TSEGs were detected in the liver and jejunum of BG-fed group, while 162 and 211 TSEGs genes were observed in the liver and jejunum of BD-fed birds, respectively. Bioinformatic analysis with both IPA and DAVID-BR further revealed a significant enrichment of DEGs and TSEGs in the biological processes for reducing the synthesis, storage, transportation and secretion of lipids in the jejunum, while those in the liver were for enhancing the oxidation of ingested lipids and fatty acids. In particular, transcriptional regulators of THRSP and EGR-1 as well as several DEGs involved in the PPAR-α signaling pathway were significantly induced by dietary BG intervention for lipid catabolism. Conclusions Our results demonstrate that BG reduces body fat deposition via regulation of gene expression, which is involved in the biological events relating to the reduction of synthesis, storage, transportation and secretion, and improvement of oxidation of lipids and fatty acids. PMID:27508934

  10. KRAS insertion mutations are oncogenic and exhibit distinct functional properties

    PubMed Central

    White, Yasmine; Bagchi, Aditi; Van Ziffle, Jessica; Inguva, Anagha; Bollag, Gideon; Zhang, Chao; Carias, Heidi; Dickens, David; Loh, Mignon; Shannon, Kevin; Firestone, Ari J.

    2016-01-01

    Oncogenic KRAS mutations introduce discrete amino acid substitutions that reduce intrinsic Ras GTPase activity and confer resistance to GTPase-activating proteins (GAPs). Here we discover a partial duplication of the switch 2 domain of K-Ras encoding a tandem repeat of amino acids G60_A66dup in a child with an atypical myeloproliferative neoplasm. K-Ras proteins containing this tandem duplication or a similar five amino acid E62_A66dup mutation identified in lung and colon cancers transform the growth of primary myeloid progenitors and of Ba/F3 cells. Recombinant K-RasG60_A66dup and K-RasE62_A66dup proteins display reduced intrinsic GTP hydrolysis rates, accumulate in the GTP-bound conformation and are resistant to GAP-mediated GTP hydrolysis. Remarkably, K-Ras proteins with switch 2 insertions are impaired for PI3 kinase binding and Akt activation, and are hypersensitive to MEK inhibition. These studies illuminate a new class of oncogenic KRAS mutations and reveal unexpected plasticity in oncogenic Ras proteins that has diagnostic and therapeutic implications. PMID:26854029

  11. Incorporating Motif Analysis into Gene Co-expression Networks Reveals Novel Modular Expression Pattern and New Signaling Pathways

    PubMed Central

    Ma, Shisong; Shah, Smit; Bohnert, Hans J.; Snyder, Michael; Dinesh-Kumar, Savithramma P.

    2013-01-01

    Understanding of gene regulatory networks requires discovery of expression modules within gene co-expression networks and identification of promoter motifs and corresponding transcription factors that regulate their expression. A commonly used method for this purpose is a top-down approach based on clustering the network into a range of densely connected segments, treating these segments as expression modules, and extracting promoter motifs from these modules. Here, we describe a novel bottom-up approach to identify gene expression modules driven by known cis-regulatory motifs in the gene promoters. For a specific motif, genes in the co-expression network are ranked according to their probability of belonging to an expression module regulated by that motif. The ranking is conducted via motif enrichment or motif position bias analysis. Our results indicate that motif position bias analysis is an effective tool for genome-wide motif analysis. Sub-networks containing the top ranked genes are extracted and analyzed for inherent gene expression modules. This approach identified novel expression modules for the G-box, W-box, site II, and MYB motifs from an Arabidopsis thaliana gene co-expression network based on the graphical Gaussian model. The novel expression modules include those involved in house-keeping functions, primary and secondary metabolism, and abiotic and biotic stress responses. In addition to confirmation of previously described modules, we identified modules that include new signaling pathways. To associate transcription factors that regulate genes in these co-expression modules, we developed a novel reporter system. Using this approach, we evaluated MYB transcription factor-promoter interactions within MYB motif modules. PMID:24098147

  12. SOX2 gene regulates the transcriptional network of oncogenes and affects tumorigenesis of human lung cancer cells.

    PubMed

    Chen, Si; Xu, Yingxi; Chen, Yanan; Li, Xuefei; Mou, Wenjun; Wang, Lina; Liu, Yanhua; Reisfeld, Ralph A; Xiang, Rong; Lv, Dan; Li, Na

    2012-01-01

    Recent studies demonstrated that cancer stem cells (CSCs) have higher tumorigenesis properties than those of differentiated cancer cells and that transcriptional factor-SOX2 plays a vital role in maintaining the unique properties of CSCs; however, the function and underlying mechanism of SOX2 in carcinogenesis of lung cancer are still elusive. This study applied immunohistochemistry to analyze the expression of SOX2 in human lung tissues of normal individuals as well as patients with adenocarcinoma, squamous cell carcinoma, and large cell and small cell carcinoma and demonstrated specific overexpression of SOX2 in all types of lung cancer tissues. This finding supports the notion that SOX2 contributes to the tumorigenesis of lung cancer cells and can be used as a diagnostic probe. In addition, obviously higher expression of oncogenes c-MYC, WNT1, WNT2, and NOTCH1 was detected in side population (SP) cells than in non-side population (NSP) cells of human lung adenocarcinoma cell line-A549, revealing a possible mechanism for the tenacious tumorigenic potential of CSCs. To further elucidate the function of SOX2 in tumorigenesis of cancer cells, A549 cells were established with expression of luciferase and doxycycline-inducible shRNA targeting SOX2. We found silencing of SOX2 gene reduces the tumorigenic property of A549 cells with attenuated expression of c-MYC, WNT1, WNT2, and NOTCH1 in xenografted NOD/SCID mice. By using the RNA-Seq method, an additional 246 target cancer genes of SOX2 were revealed. These results present evidence that SOX2 may regulate the expression of oncogenes in CSCs to promote the development of human lung cancer.

  13. Systems-level analysis reveals selective regulation of Aqp2 gene expression by vasopressin

    PubMed Central

    Sandoval, Pablo C.; Claxton, J’Neka S.; Lee, Jae Wook; Saeed, Fahad; Hoffert, Jason D.; Knepper, Mark A.

    2016-01-01

    Vasopressin-mediated regulation of renal water excretion is defective in a variety of water balance disorders in humans. It occurs in part through long-term mechanisms that regulate the abundance of the aquaporin-2 water channel in renal collecting duct cells. Here, we use deep DNA sequencing in mouse collecting duct cells to ask whether vasopressin signaling selectively increases Aqp2 gene transcription or whether it triggers a broadly targeted transcriptional network. ChIP-Seq quantification of binding sites for RNA polymerase II was combined with RNA-Seq quantification of transcript abundances to identify genes whose transcription is regulated by vasopressin. (View curated dataset at https://helixweb.nih.gov/ESBL/Database/Vasopressin/). The analysis revealed only 35 vasopressin-regulated genes (of 3659) including Aqp2. Increases in RNA polymerase II binding and mRNA abundances for Aqp2 far outstripped corresponding measurements for all other genes, consistent with the conclusion that vasopressin-mediated transcriptional regulation is highly selective for Aqp2. Despite the overall selectivity of the net transcriptional response, vasopressin treatment was associated with increased RNA polymerase II binding to the promoter proximal region of a majority of expressed genes, suggesting a nearly global positive regulation of transcriptional initiation with transcriptional pausing. Thus, the overall net selectivity appears to be a result of selective control of transcriptional elongation. PMID:27725713

  14. Changes in cecal microbiota and mucosal gene expression revealed new aspects of epizootic rabbit enteropathy.

    PubMed

    Bäuerl, Christine; Collado, M Carmen; Zúñiga, Manuel; Blas, Enrique; Pérez Martínez, Gaspar

    2014-01-01

    Epizootic Rabbit Enteropathy (ERE) is a severe disease of unknown aetiology that mainly affects post-weaning animals. Its incidence can be prevented by antibiotic treatment suggesting that bacterial elements are crucial for the development of the disease. Microbial dynamics and host responses during the disease were studied. Cecal microbiota was characterized in three rabbit groups (ERE-affected, healthy and healthy pretreated with antibiotics), followed by transcriptional analysis of cytokines and mucins in the cecal mucosa and vermix by q-rtPCR. In healthy animals, cecal microbiota with or without antibiotic pretreatment was very similar and dominated by Alistipes and Ruminococcus. Proportions of both genera decreased in ERE rabbits whereas Bacteroides, Akkermansia and Rikenella increased, as well as Clostridium, γ-Proteobacteria and other opportunistic and pathogenic species. The ERE group displayed remarkable dysbiosis and reduced taxonomic diversity. Transcription rate of mucins and inflammatory cytokines was very high in ERE rabbits, except IL-2, and its analysis revealed the existence of two clearly different gene expression patterns corresponding to Inflammatory and (mucin) Secretory Profiles. Furthermore, these profiles were associated to different bacterial species, suggesting that they may correspond to different stages of the disease. Other data obtained in this work reinforced the notion that ERE morbidity and mortality is possibly caused by an overgrowth of different pathogens in the gut of animals whose immune defence mechanisms seem not to be adequately responding.

  15. Changes in Cecal Microbiota and Mucosal Gene Expression Revealed New Aspects of Epizootic Rabbit Enteropathy

    PubMed Central

    Zúñiga, Manuel; Blas, Enrique; Pérez Martínez, Gaspar

    2014-01-01

    Epizootic Rabbit Enteropathy (ERE) is a severe disease of unknown aetiology that mainly affects post-weaning animals. Its incidence can be prevented by antibiotic treatment suggesting that bacterial elements are crucial for the development of the disease. Microbial dynamics and host responses during the disease were studied. Cecal microbiota was characterized in three rabbit groups (ERE-affected, healthy and healthy pretreated with antibiotics), followed by transcriptional analysis of cytokines and mucins in the cecal mucosa and vermix by q-rtPCR. In healthy animals, cecal microbiota with or without antibiotic pretreatment was very similar and dominated by Alistipes and Ruminococcus. Proportions of both genera decreased in ERE rabbits whereas Bacteroides, Akkermansia and Rikenella increased, as well as Clostridium, γ-Proteobacteria and other opportunistic and pathogenic species. The ERE group displayed remarkable dysbiosis and reduced taxonomic diversity. Transcription rate of mucins and inflammatory cytokines was very high in ERE rabbits, except IL-2, and its analysis revealed the existence of two clearly different gene expression patterns corresponding to Inflammatory and (mucin) Secretory Profiles. Furthermore, these profiles were associated to different bacterial species, suggesting that they may correspond to different stages of the disease. Other data obtained in this work reinforced the notion that ERE morbidity and mortality is possibly caused by an overgrowth of different pathogens in the gut of animals whose immune defence mechanisms seem not to be adequately responding. PMID:25147938

  16. Oncogenic potential of bifunctional bioreductive drugs.

    PubMed

    Hei, T K; Liu, S X; Hall, E J

    1996-07-01

    Potential oncogenicity must be a factor of concern in the design and development of novel bioreductive drugs. In the present studies, the cytotoxicity and oncogenic transforming potential of a series of heterocyclic mono-N-oxides, designed to be used as bioreductive drugs, were examined using the mouse C3H 10T1/2 cell system. Exponential phase cultures of 10T1/2 cells were treated with graded doses of the bioreductive drugs for a 4 h period, either in air or hypoxia, at 37 degrees C. After treatment, cultures were replated for both survival and transformation assays. The fused pyrazine mono-N-oxide RB 90740 and its N-deoxy analogue, RB 92816, demonstrated a dose-dependent cytotoxicity and oncogenic transforming potency under aerobic conditions. Similarly, the indoloquinone E09 and the structurally related mitomycin C demonstrated dose dependence in both toxicity and oncogenic transforming potential. The most cytotoxic aromatic-N-oxides tested, RB 92816, also demonstrated the highest oncogenic transformation incidence. In hypoxia, the bioreductive metabolites of RB 90740 were substantially more cytotoxic and induced a higher oncogenic transformation yield than the drug in air. These data are consistent with the structure-activity relationship for bioreductive drugs in that heterocyclic-N-oxides with reactive side chains such as RB 92816 are cytotoxic and potentially carcinogenic.

  17. Characterization of the human oncogene SCL/TAL1 interrupting locus (Stil) mediated Sonic hedgehog (Shh) signaling transduction in proliferating mammalian dopaminergic neurons

    SciTech Connect

    Sun, Lei; Carr, Aprell L.; Li, Ping; Lee, Jessica; McGregor, Mary; Li, Lei

    2014-07-11

    Highlights: • Stil is a human oncogene that is conserved in vertebrate species. • Stil functions in the Shh pathway in mammalian cells. • The expression of Stil is required for mammalian dopaminergic cell proliferation. - Abstract: The human oncogene SCL/TAL1 interrupting locus (Stil) is highly conserved in all vertebrate species. In humans, the expression of Stil is involved in cancer cell survival, apoptosis and proliferation. In this research, we investigated the roles of Stil expression in cell proliferation of mammalian dopaminergic (DA) PC12 cells. Stil functions through the Sonic hedgehog (Shh) signal transduction pathway. Co-immunoprecipitation tests revealed that STIL interacts with Shh downstream components, which include SUFU and GLI1. By examining the expression of Stil, Gli1, CyclinD2 (cell-cycle marker) and PCNA (proliferating cell nuclear antigen), we found that up-regulation of Stil expression (transfection with overexpression plasmids) increased Shh signaling transduction and PC12 cell proliferation, whereas down-regulation of Stil expression (by shRNA) inhibited Shh signaling transduction, and thereby decreased PC12 cell proliferation. Transient transfection of PC12 cells with Stil knockdown or overexpression plasmids did not affect PC12 cell neural differentiation, further indicating the specific roles of Stil in cell proliferation. The results from this research suggest that Stil may serve as a bio-marker for neurological diseases involved in DA neurons, such as Parkinson’s disease.

  18. Analysis of global gene expression in Brachypodium distachyon reveals extensive network plasticity in response to abiotic stress.

    PubMed

    Priest, Henry D; Fox, Samuel E; Rowley, Erik R; Murray, Jessica R; Michael, Todd P; Mockler, Todd C

    2014-01-01

    Brachypodium distachyon is a close relative of many important cereal crops. Abiotic stress tolerance has a significant impact on productivity of agriculturally important food and feedstock crops. Analysis of the transcriptome of Brachypodium after chilling, high-salinity, drought, and heat stresses revealed diverse differential expression of many transcripts. Weighted Gene Co-Expression Network Analysis revealed 22 distinct gene modules with specific profiles of expression under each stress. Promoter analysis implicated short DNA sequences directly upstream of module members in the regulation of 21 of 22 modules. Functional analysis of module members revealed enrichment in functional terms for 10 of 22 network modules. Analysis of condition-specific correlations between differentially expressed gene pairs revealed extensive plasticity in the expression relationships of gene pairs. Photosynthesis, cell cycle, and cell wall expression modules were down-regulated by all abiotic stresses. Modules which were up-regulated by each abiotic stress fell into diverse and unique gene ontology GO categories. This study provides genomics resources and improves our understanding of abiotic stress responses of Brachypodium.

  19. Potential role of O-GlcNAcylation and involvement of PI3K/Akt1 pathway in the expression of oncogenic phenotypes of gastric cancer cells in vitro.

    PubMed

    Zhang, Nuobei; Chen, Xin

    2016-11-01

    O-GlcNAcylation is a monosaccharide modification by a residue of N-acetylglucosamine (GlcNAc) attached to serine or threonine moieties on nuclear and cytoplasmic proteins. O-GlcNAcylation is dynamically regulated by O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA). Increasing evidence suggests that O-GlcNAcylation is involved in a variety of human cancers. However, the exact role of O-GlcNAcylation in tumor progression remains unclear. Here, we show that O-GlcNAcylation accelerates oncogenic phenotypes of gastric cancer. First, cell models with increased or decreased O-GlcNAcylation were constructed by OGT overexpression, downregulation of OGA activity with specific inhibitor Thiamet-G, or silence of OGT. MTT assays indicated that O-GlcNAcylation increased proliferation of gastric cancer cells. Soft agar assay and Transwell assays showed that O-GlcNAcylation significantly enhanced cellular colony formation, migration, and invasion in vitro. Akt1 activity was stimulated by upregulation of phosphorylation at Ser473 mediated by elevated O-GlcNAcylation. The enhanced cell invasion by Thiamet-G treatment was suppressed by PI3K inhibitor LY294002. Although the cell invasion induced by Thiamet-G was reduced by Akt1 shRNA, it was still higher in comparison with that to the control (cells with Akt1 shRNA alone). And Akt1 overexpression promoted Thiamet-G-induced cell invasion. These results suggested that O-GlcNAcylation enhanced oncogenic phenotypes possibly partially involving PI3K/Akt signaling pathway.

  20. Single-cell RNA-seq reveals dynamic, random monoallelic gene expression in mammalian cells.

    PubMed

    Deng, Qiaolin; Ramsköld, Daniel; Reinius, Björn; Sandberg, Rickard

    2014-01-10

    Expression from both alleles is generally observed in analyses of diploid cell populations, but studies addressing allelic expression patterns genome-wide in single cells are lacking. Here, we present global analyses of allelic expression across individual cells of mouse preimplantation embryos of mixed background (CAST/EiJ × C57BL/6J). We discovered abundant (12 to 24%) monoallelic expression of autosomal genes and that expression of the two alleles occurs independently. The monoallelic expression appeared random and dynamic because there was considerable variation among closely related embryonic cells. Similar patterns of monoallelic expression were observed in mature cells. Our allelic expression analysis also demonstrates the de novo inactivation of the paternal X chromosome. We conclude that independent and stochastic allelic transcription generates abundant random monoallelic expression in the mammalian cell.

  1. Minimal contribution of ERK1/2-MAPK signalling towards the maintenance of oncogenic GNAQQ209P-driven uveal melanomas in zebrafish

    PubMed Central

    Mouti, Mai Abdel; Dee, Christopher; Coupland, Sarah E.; Hurlstone, Adam F.L.

    2016-01-01

    Mutations affecting Gαq proteins are pervasive in uveal melanoma (UM), suggesting they ‘drive’ UM pathogenesis. The ERK1/2-MAPK pathway is critical for cutaneous melanoma development and consequently an important therapeutic target. Defining the contribution of ERK1/2-MAPK signalling to UM development has been hampered by the lack of an informative animal model that spontaneously develops UM. Towards this end, we engineered transgenic zebrafish to express oncogenic GNAQQ209P in the melanocyte lineage. This resulted in hyperplasia of uveal melanocytes, but with no evidence of malignant progression, nor perturbation of skin melanocytes. Combining expression of oncogenic GNAQQ209P with p53 inactivation resulted in earlier onset and even more extensive hyperplasia of uveal melanocytes that progressed to UM. Immunohistochemistry revealed only weak immunoreactivity to phosphorylated (p)ERK1/2 in established uveal tumours—in contrast to strong immunoreactivity in oncogenic RAS-driven skin lesions—but ubiquitous positive staining for nuclear Yes-associated protein (YAP). Moreover, no changes were observed in pERK1/2 levels upon transient knockdown of GNAQ or phospholipase C-beta (PLC-β) inhibition in the majority of human UM cell lines we tested harbouring GNAQ mutations. In summary, our findings demonstrate a weak correlation between oncogenic GNAQQ209P mutation and sustained ERK1/2-MAPK activation, implying that ERK1/2 signalling is unlikely to be instrumental in the maintenance of GNAQQ209P-driven UMs. PMID:27166257

  2. REST regulates oncogenic properties of glioblastoma stem cells

    PubMed Central

    Kamal, Mohamed M.; Sathyan, Pratheesh; Singh, Sanjay K.; Zinn, Pascal O.; Marisetty, Anantha L.; Liang, Shoudan; Gumin, Joy; El-Mesallamy, Hala Osman; Suki, Dima; Colman, Howard; Fuller, Gregory N.; Lang, Frederick F.; Majumder, Sadhan

    2013-01-01

    Glioblastoma multiforme (GBM) tumors are the most common malignant primary brain tumors in adults. Although many GBM tumors are believed to be caused by self-renewing, glioblastoma-derived stem-like cells (GSCs), the mechanisms that regulate self-renewal and other oncogenic properties of GSCs are only now being unraveled. Here we showed that GSCs derived from GBM patient specimens express varying levels of the transcriptional repressor REST, suggesting heterogeneity across different GSC lines. Loss- and gain-of-function experiments indicated that REST maintains self-renewal of GSCs. High REST-expressing GSCs (HR-GSCs) produced tumors histopathologically distinct from those generated by low REST-expressing GSCs (LR-GSCs) in orthotopic mouse brain tumor models. Knockdown of REST in HR-GSCs resulted in increased survival in GSC-transplanted mice and produced tumors with higher apoptotic and lower invasive properties. Conversely, forced expression of exogenous REST in LR-GSCs produced decreased survival in mice and produced tumors with lower apoptotic and higher invasive properties, similar to HR-GSCs. Thus, based on our results, we propose that a novel function of REST is to maintain self-renewal and other oncogenic properties of GSCs and that REST can play a major role in mediating tumorigenicity in GBM. PMID:22228704

  3. Expression Profile of the Schistosoma japonicum Degradome Reveals Differential Protease Expression Patterns and Potential Anti-schistosomal Intervention Targets

    PubMed Central

    Liu, Shuai; Cai, Pengfei; Piao, Xianyu; Hou, Nan; Zhou, Xiaosu; Wu, Chuang; Wang, Heng; Chen, Qijun

    2014-01-01

    Blood fluke proteases play pivotal roles in the processes of invasion, nutrition acquisition, immune evasion, and other host-parasite interactions. Hundreds of genes encoding putative proteases have been identified in the recently published schistosome genomes. However, the expression profiles of these proteases in Schistosoma species have not yet been systematically analyzed. We retrieved and culled the redundant protease sequences of Schistosoma japonicum, Schistosoma mansoni, Echinococcus multilocularis, and Clonorchis sinensis from public databases utilizing bioinformatic approaches. The degradomes of the four parasitic organisms and Homo sapiens were then comparatively analyzed. A total of 262 S. japonicum protease sequences were obtained and the expression profiles generated using whole-genome microarray. Four main clusters of protease genes with different expression patterns were identified: proteases up-regulated in hepatic schistosomula and adult worms, egg-specific or predominantly expressed proteases, cercaria-specific or predominantly expressed proteases, and constantly expressed proteases. A subset of protease genes with different expression patterns were further validated using real-time quantitative PCR. The present study represents the most comprehensive analysis of a degradome in Schistosoma species to date. These results provide a firm foundation for future research on the specific function(s) of individual proteases and may help to refine anti-proteolytic strategies in blood flukes. PMID:25275570

  4. Genes Expressed in Grapevine Leaves Reveal Latent Wood Infection by the Fungal Pathogen Neofusicoccum parvum

    PubMed Central

    Czemmel, Stefan; Galarneau, Erin R.; Travadon, Renaud; McElrone, Andrew J.; Cramer, Grant R.; Baumgartner, Kendra

    2015-01-01

    Some pathogenic species of the Botryosphaeriaceae have a latent phase, colonizing woody tissues while perennial hosts show no apparent symptoms until conditions for disease development become favorable. Detection of these pathogens is often limited to the later pathogenic phase. The latent phase is poorly characterized, despite the need for non-destructive detection tools and effective quarantine strategies, which would benefit from identification of host-based markers in leaves. Neofusicoccum parvum infects the wood of grapevines and other horticultural crops, killing the fruit-bearing shoots. We used light microscopy and high-resolution computed tomography (HRCT) to examine the spatio-temporal relationship between pathogen colonization and anatomical changes in stem sections. To identify differentially-expressed grape genes, leaves from inoculated and non-inoculated plants were examined using RNA-Seq. The latent phase occurred between 0 and 1.5 months post-inoculation (MPI), during which time the pathogen did not spread significantly beyond the inoculation site nor were there differences in lesion lengths between inoculated and non-inoculated plants. The pathogenic phase occurred between 1.5 and 2 MPI, when recovery beyond the inoculation site increased and lesion lengths of inoculated plants tripled. By 2 MPI, inoculated plants also had decreased starch content in xylem fibers and rays, and increased levels of gel-occluded xylem vessels, the latter of which HRCT revealed at a higher frequency than microscopy. RNA-Seq and screening of 21 grape expression datasets identified 20 candidate genes that were transcriptionally-activated by infection during the latent phase, and confirmed that the four best candidates (galactinol synthase, abscisic acid-induced wheat plasma membrane polypeptide-19 ortholog, embryonic cell protein 63, BURP domain-containing protein) were not affected by a range of common foliar and wood pathogens or abiotic stresses. Assuming such host

  5. Genes expressed in grapevine leaves reveal latent wood infection by the fungal pathogen Neofusicoccum parvum.

    PubMed

    Czemmel, Stefan; Galarneau, Erin R; Travadon, Renaud; McElrone, Andrew J; Cramer, Grant R; Baumgartner, Kendra

    2015-01-01

    Some pathogenic species of the Botryosphaeriaceae have a latent phase, colonizing woody tissues while perennial hosts show no apparent symptoms until conditions for disease development become favorable. Detection of these pathogens is often limited to the later pathogenic phase. The latent phase is poorly characterized, despite the need for non-destructive detection tools and effective quarantine strategies, which would benefit from identification of host-based markers in leaves. Neofusicoccum parvum infects the wood of grapevines and other horticultural crops, killing the fruit-bearing shoots. We used light microscopy and high-resolution computed tomography (HRCT) to examine the spatio-temporal relationship between pathogen colonization and anatomical changes in stem sections. To identify differentially-expressed grape genes, leaves from inoculated and non-inoculated plants were examined using RNA-Seq. The latent phase occurred between 0 and 1.5 months post-inoculation (MPI), during which time the pathogen did not spread significantly beyond the inoculation site nor were there differences in lesion lengths between inoculated and non-inoculated plants. The pathogenic phase occurred between 1.5 and 2 MPI, when recovery beyond the inoculation site increased and lesion lengths of inoculated plants tripled. By 2 MPI, inoculated plants also had decreased starch content in xylem fibers and rays, and increased levels of gel-occluded xylem vessels, the latter of which HRCT revealed at a higher frequency than microscopy. RNA-Seq and screening of 21 grape expression datasets identified 20 candidate genes that were transcriptionally-activated by infection during the latent phase, and confirmed that the four best candidates (galactinol synthase, abscisic acid-induced wheat plasma membrane polypeptide-19 ortholog, embryonic cell protein 63, BURP domain-containing protein) were not affected by a range of common foliar and wood pathogens or abiotic stresses. Assuming such host

  6. Oncogenes and inflammation rewire host energy metabolism in the tumor microenvironment

    PubMed Central

    Martinez-Outschoorn, Ubaldo E; Curry, Joseph M; Ko, Ying-Hui; Lin, Zhao; Tuluc, Madalina; Cognetti, David; Birbe, Ruth C; Pribitkin, Edmund; Bombonati, Alessandro; Pestell, Richard G; Howell, Anthony; Sotgia, Federica; Lisanti, Michael P

    2013-01-01

    Here, we developed a model system to evaluate the metabolic effects of oncogene(s) on the host microenvironment. A matched set of “normal” and oncogenically transformed epithelial cell lines were co-cultured with human fibroblasts, to determine the “bystander” effects of oncogenes on stromal cells. ROS production and glucose uptake were measured by FACS analysis. In addition, expression of a panel of metabolic protein biomarkers (Caveolin-1, MCT1, and MCT4) was analyzed in parallel. Interestingly, oncogene activation in cancer cells was sufficient to induce the metabolic reprogramming of cancer-associated fibroblasts toward glycolysis, via oxidative stress. Evidence for “metabolic symbiosis” between oxidative cancer cells and glycolytic fibroblasts was provided by MCT1/4 immunostaining. As such, oncogenes drive the establishment of a stromal-epithelial “lactate-shuttle”, to fuel the anabolic growth of cancer cells. Similar results were obtained with two divergent oncogenes (RAS and NFκB), indicating that ROS production and inflammation metabolically converge on the tumor stroma, driving glycolysis and upregulation of MCT4. These findings make stromal MCT4 an attractive target for new drug discovery, as MCT4 is a shared endpoint for the metabolic effects of many oncogenic stimuli. Thus, diverse oncogenes stimulate a common metabolic response in the tumor stroma. Conversely, we also show that fibroblasts protect cancer cells against oncogenic stress and senescence by reducing ROS production in tumor cells. Ras-transformed cells were also able to metabolically reprogram normal adjacent epithelia, indicating that cancer cells can use either fibroblasts or epithelial cells as “partners” for metabolic symbiosis. The antioxidant N-acetyl-cysteine (NAC) selectively halted mitochondrial biogenesis in Ras-transformed cells, but not in normal epithelia. NAC also blocked stromal induction of MCT4, indicating that NAC effectively functions as an “MCT4

  7. Gene expression analysis of tuberous sclerosis complex cortical tubers reveals increased expression of adhesion and inflammatory factors

    PubMed Central

    Boer, Karin; Crino, Peter B.; Gorter, Jan A.; Nellist, Mark; Jansen, Floor E.; Spliet, Wim G.M.; van Rijen, Peter C.; Wittink, Floyd R.A.; Breit, Timo M.; Troost, Dirk; Wadman, Wytse J.; Aronica, Eleonora

    2009-01-01

    Cortical tubers in patients with tuberous sclerosis complex are associated with disabling neurological manifestations, including intractable epilepsy. While these malformations are believed to result from the effects of TSC1 or TSC2 gene mutations, the molecular mechanisms leading to tuber formation, as well as the onset of seizures remain largely unknown. We used the Affymetrix Gene Chip platform to provide the first genome wide investigation of gene expression in surgically resected tubers, compared with histological normal perituberal tissue from the same patients or autopsy control tissue. We identified 2501 differentially expressed genes in cortical tubers compared with autopsy controls. Expression of genes associated with cell adhesion e.g., VCAM1, integrins and CD44, or with the inflammatory response, including complement factors, serpinA3, CCL2 and several cytokines, was increased in cortical tubers, whereas genes related to synaptic transmission e.g., the glial glutamate transporter GLT-1, and voltage-gated channel activity, exhibited lower expression. Gene expression in perituberal cortex was distinct from autopsy control cortex suggesting that even in the absence of tissue pathology the transcriptome is altered in TSC. Changes in gene expression yield insights into new candidate genes that may contribute to tuber formation or seizure onset, representing new targets for potential therapeutic development. PMID:19912235

  8. BCL3 exerts an oncogenic function by regulating STAT3 in human cervical cancer

    PubMed Central

    Zhao, Hu; Wang, Wuliang; Zhao, Qinghe; Hu, Guiming; Deng, Kehong; Liu, Yuling

    2016-01-01

    Aberrant expression of oncogenes and/or tumor suppressors play a fundamental effect on the pathogenesis and tumorigenicity of cervical cancer (CC). B-cell CLL/lymphoma 3 (BCL3) was previously found to be a putative proto-oncogene in human cancers and regulated signal transducer and activator of transcription 3 (STAT3), a critical oncogene, in CC cell line. However, its expression status, clinical significance and biological functions in CC remain largely unclear. The expressions of BCL3 and STAT3 in CC specimens were determined by immunohistochemistry. MTT, colony formation assays and flow cytometry analysis were carried out to test proliferation and cell cycle of CC cells. Here, the levels of BCL3 were overexpressed in CC compared to adjacent cervical tissues. Furthermore, high levels of BCL3 protein were confirmed by immunoblotting in CC cells as compared with normal cervical epithelial cells. The positive expression of BCL3 was correlated with adverse prognostic features and reduced survival rate. In addition, BCL3 regulated STAT3 abundance in CC cells. STAT3 was found to be upregulated and positively correlated with BCL3 expression in CC specimens. BCL3 overexpression resulted in prominent increased proliferation and cell cycle progression in Hela cells. By contrast, inhibition of BCL3 in CaSki cells remarkably suppressed proliferative ability and cell cycle progression. In vivo studies showed that knockdown of BCL3 inhibited tumor growth of CC in mice xenograft model. Notably, we confirmed that STAT3 mediated the oncogenic roles of BCL3 in CC. In conclusion, we suggest that BCL3 serves as an oncogene in CC by modulating proliferation and cell cycle progression, and its oncogenic effect is mediated by its downstream target gene, STAT3. PMID:27822067

  9. Oncogenic PTEN functions and models in T-cell malignancies.

    PubMed

    Tesio, M; Trinquand, A; Macintyre, E; Asnafi, V

    2016-07-28

    PTEN is a protein phosphatase that is crucial to prevent the malignant transformation of T-cells. Although a numerous mechanisms regulate its expression and function, they are often altered in T-cell acute lymphoblastic leukaemias and T-cell lymphomas. As such, PTEN inactivation frequently occurs in these malignancies, where it can be associated with chemotherapy resistance and poor prognosis. Different Pten knockout models recapitulated the development of T-cell leukaemia/lymphoma, demonstrating that PTEN loss is at the center of a complex oncogenic network that sustains and drives tumorigenesis via the activation of multiple signalling pathways. These aspects and their therapeutic implications are discussed in this review.

  10. The activating transcription factor 3 protein suppresses the oncogenic function of mutant p53 proteins.

    PubMed

    Wei, Saisai; Wang, Hongbo; Lu, Chunwan; Malmut, Sarah; Zhang, Jianqiao; Ren, Shumei; Yu, Guohua; Wang, Wei; Tang, Dale D; Yan, Chunhong

    2014-03-28

    Mutant p53 proteins (mutp53) often acquire oncogenic activities, conferring drug resistance and/or promoting cancer cell migration and invasion. Although it has been well established that such a gain of function is mainly achieved through interaction with transcriptional regulators, thereby modulating cancer-associated gene expression, how the mutp53 function is regulated remains elusive. Here we report that activating transcription factor 3 (ATF3) bound common mutp53 (e.g. R175H and R273H) and, subsequently, suppressed their oncogenic activities. ATF3 repressed mutp53-induced NFKB2 expression and sensitized R175H-expressing cancer cells to cisplatin and etoposide treatments. Moreover, ATF3 appeared to suppress R175H- and R273H-mediated cancer cell migration and invasion as a consequence of preventing the transcription factor p63 from inactivation by mutp53. Accordingly, ATF3 promoted the expression of the metastasis suppressor SHARP1 in mutp53-expressing cells. An ATF3 mutant devoid of the mutp53-binding domain failed to disrupt the mutp53-p63 binding and, thus, lost the activity to suppress mutp53-mediated migration, suggesting that ATF3 binds to mutp53 to suppress its oncogenic function. In line with these results, we found that down-regulation of ATF3 expression correlated with lymph node metastasis in TP53-mutated human lung cancer. We conclude that ATF3 can suppress mutp53 oncogenic function, thereby contributing to tumor suppression in TP53-mutated cancer.

  11. Large Scale Gene Expression Meta-Analysis Reveals Tissue-Specific, Sex-Biased Gene Expression in Humans

    PubMed Central

    Mayne, Benjamin T.; Bianco-Miotto, Tina; Buckberry, Sam; Breen, James; Clifton, Vicki; Shoubridge, Cheryl; Roberts, Claire T.

    2016-01-01

    The severity and prevalence of many diseases are known to differ between the sexes. Organ specific sex-biased gene expression may underpin these and other sexually dimorphic traits. To further our understanding of sex differences in transcriptional regulation, we performed meta-analyses of sex biased gene expression in multiple human tissues. We analyzed 22 publicly available human gene expression microarray data sets including over 2500 samples from 15 different tissues and 9 different organs. Briefly, by using an inverse-variance method we determined the effect size difference of gene expression between males and females. We found the greatest sex differences in gene expression in the brain, specifically in the anterior cingulate cortex, (1818 genes), followed by the heart (375 genes), kidney (224 genes), colon (218 genes), and thyroid (163 genes). More interestingly, we found different parts of the brain with varying numbers and identity of sex-biased genes, indicating that specific cortical regions may influence sexually dimorphic traits. The majority of sex-biased genes in other tissues such as the bladder, liver, lungs, and pancreas were on the sex chromosomes or involved in sex hormone production. On average in each tissue, 32% of autosomal genes that were expressed in a sex-biased fashion contained androgen or estrogen hormone response elements. Interestingly, across all tissues, we found approximately two-thirds of autosomal genes that were sex-biased were not under direct influence of sex hormones. To our knowledge this is the largest analysis of sex-biased gene expression in human tissues to date. We identified many sex-biased genes that were not under the direct influence of sex chromosome genes or sex hormones. These may provide targets for future development of sex-specific treatments for diseases. PMID:27790248

  12. Spi-1, Fli-1 and Fli-3 (miR-17-92) Oncogenes Contribute to a Single Oncogenic Network Controlling Cell Proliferation in Friend Erythroleukemia

    PubMed Central

    Kayali, Samer; Giraud, Guillaume; Morlé, François; Guyot, Boris

    2012-01-01

    Clonal erythroleukemia developing in susceptible mice infected by Friend virus complex are associated with highly recurrent proviral insertions at one of three loci called Spi-1, Fli-1 or Fli-3, leading to deregulated expression of oncogenic Spi-1 or Fli-1 transcription factors or miR-17-92 miRNA cluster, respectively. Deregulated expression of each of these three oncogenes has been independently shown to contribute to cell proliferation of erythroleukemic clones. Previous studies showed a close relationship between Spi-1 and Fli-1, which belong to the same ETS family, Spi-1 activating fli-1 gene, and both Spi-1 and Fli-1 activating multiple common target genes involved in ribosome biogenesis. In this study, we demonstrated that Spi-1 and Fli-1 are also involved in direct miR-17-92 transcriptional activation through their binding to a conserved ETS binding site in its promoter. Moreover, we demonstrated that physiological re-expression of exogenous miR-17 and miR-20a are able to partially rescue the proliferation loss induced by Fli-1 knock-down and identified HBP1 as a target of these miRNA in erythroleukemic cells. These results establish that three of the most recurrently activated oncogenes in Friend erythroleukemia are actually involved in a same oncogenic network controlling cell proliferation. The putative contribution of a similar ETS-miR-17-92 network module in other normal or pathological proliferative contexts is discussed. PMID:23056458

  13. Spi-1, Fli-1 and Fli-3 (miR-17-92) oncogenes contribute to a single oncogenic network controlling cell proliferation in friend erythroleukemia.

    PubMed

    Kayali, Samer; Giraud, Guillaume; Morlé, François; Guyot, Boris

    2012-01-01

    Clonal erythroleukemia developing in susceptible mice infected by Friend virus complex are associated with highly recurrent proviral insertions at one of three loci called Spi-1, Fli-1 or Fli-3, leading to deregulated expression of oncogenic Spi-1 or Fli-1 transcription factors or miR-17-92 miRNA cluster, respectively. Deregulated expression of each of these three oncogenes has been independently shown to contribute to cell proliferation of erythroleukemic clones. Previous studies showed a close relationship between Spi-1 and Fli-1, which belong to the same ETS family, Spi-1 activating fli-1 gene, and both Spi-1 and Fli-1 activating multiple common target genes involved in ribosome biogenesis. In this study, we demonstrated that Spi-1 and Fli-1 are also involved in direct miR-17-92 transcriptional activation through their binding to a conserved ETS binding site in its promoter. Moreover, we demonstrated that physiological re-expression of exogenous miR-17 and miR-20a are able to partially rescue the proliferation loss induced by Fli-1 knock-down and identified HBP1 as a target of these miRNA in erythroleukemic cells. These results establish that three of the most recurrently activated oncogenes in Friend erythroleukemia are actually involved in a same oncogenic network controlling cell proliferation. The putative contribution of a similar ETS-miR-17-92 network module in other normal or pathological proliferative contexts is discussed.

  14. Hedgehog Signal Transduction: Key Players, Oncogenic Drivers, and Cancer Therapy.

    PubMed

    Pak, Ekaterina; Segal, Rosalind A

    2016-08-22

    The Hedgehog (Hh) signaling pathway governs complex developmental processes, including proliferation and patterning within diverse tissues. These activities rely on a tightly regulated transduction system that converts graded Hh input signals into specific levels of pathway activity. Uncontrolled activation of Hh signaling drives tumor initiation and maintenance. However, recent entry of pathway-specific inhibitors into the clinic reveals mixed patient responses and thus prompts further exploration of pathway activation and inhibition. In this review, we share emerging insights into regulated and oncogenic Hh signaling, supplemented with updates on the development and use of Hh pathway-targeted therapies.

  15. Comparative gene expression analysis among vocal learners (bengalese finch and budgerigar) and non-learners (quail and ring dove) reveals variable cadherin expressions in the vocal system.

    PubMed

    Matsunaga, Eiji; Okanoya, Kazuo

    2011-01-01

    Birds use various vocalizations to communicate with one another, and some are acquired through learning. So far, three families of birds (songbirds, parrots, and hummingbirds) have been identified as having vocal learning ability. Previously, we found that cadherins, a large family of cell-adhesion molecules, show vocal control-area-related expression in a songbird, the Bengalese finch. To investigate the molecular basis of evolution in avian species, we conducted comparative analysis of cadherin expressions in the vocal and other neural systems among vocal learners (Bengalese finch and budgerigar) and a non-learner (quail and ring dove). The gene expression analysis revealed that cadherin expressions were more variable in vocal and auditory areas compared to vocally unrelated areas such as the visual areas among these species. Thus, it appears that such diverse cadherin expressions might have been related to generating species diversity in vocal behavior during the evolution of avian vocal learning.

  16. Gene Expression Profiling Reveals Early Cellular Responses to Intracellular Magnetic Labeling with Superparamagnetic Iron Oxide Nanoparticles

    PubMed Central

    Kedziorek, Dorota A.; Muja, Naser; Walczak, Piotr; Ruiz-Cabello, Jesus; Gilad, Assaf A.; Jie, Chunfa C.; Bulte, Jeff W. M.

    2010-01-01

    With MRI (stem) cell tracking having entered the clinic, studies on the cellular genomic response toward labeling are warranted. Gene expression profiling was applied to C17.2 neural stem cells following superparamagnetic iron oxide/PLL (poly-L-lysine) labeling over the course of 1 week. Relative to unlabeled cells, less than 1% of genes (49 total) exhibited greater than 2-fold difference in expression in response to superparamagnetic iron oxide/PLL labeling. In particular, transferrin receptor 1 (Tfrc) and heme oxygenase 1 (Hmox1) expression was downregulated early, whereas genes involved in lysosomal function (Sulf1) and detoxification (Clu, Cp, Gstm2, Mgst1) were upregulated at later time points. Relative to cells treated with PLL only, cells labeled with superparamagnetic iron oxide/PLL complexes exhibited differential expression of 1399 genes. Though these differentially expressed genes exhibited altered expression over time, the overall extent was limited. Gene ontology analysis of differentially expressed genes showed that genes encoding zinc-binding proteins are enriched after superparamagnetic iron oxide/PLL labeling relative to PLL only treatment, whereas members of the apoptosis/ programmed cell death pathway did not display increased expression. Overexpression of the differentially expressed genes Rnf138 and Abcc4 were confirmed by quantitative real-time polymerase chain reaction. These results demonstrate that, although early reactions responsible for iron homeostasis are induced, overall neural stem cell gene expression remains largely unaltered following superparamagnetic iron oxide/PLL labeling. PMID:20373404

  17. Oncogenicity of the developmental transcription factor Sox9

    PubMed Central

    Matheu, Ander; Collado, Manuel; Wise, Clare; Manterola, Lorea; Cekaite, Lina; Tye, Angela J.; Canamero, Marta; Bujanda, Luis; Schedl, Andreas; Cheah, Kathryn S.E.; Skotheim, Rolf I.; Lothe, Ragnhild A.; de Munain, Adolfo López; Briscoe, James; Serrano, Manuel; Lovell-Badge, Robin

    2012-01-01

    SOX9, a high mobility group (HMG) box transcription factor, plays critical roles during embryogenesis and its activity is required for development, differentiation and lineage commitment in various tissues including the intestinal epithelium. Here, we present functional and clinical data of a broadly important role for SOX9 in tumorigenesis. SOX9 was overexpressed in a wide range of human cancers, where its expression correlated with malignant character and progression. Gain of SOX9 copy number is detected in some primary colorectal cancers. SOX9 exhibited several pro-oncogenic properties, including the ability to promote proliferation, inhibit senescence and collaborate with other oncogenes in neoplastic transformation. In primary MEFs and colorectal cancer cells, SOX9 expression facilitated tumor growth and progression whilst its inactivation reduced tumorigenicity. Mechanistically, we have found that Sox9 directly binds and activates the promoter of the polycomb protein Bmi1, whose upregulation represses the tumor suppressor Ink4a/Arf locus. In agreement with this, human colorectal cancers showed a positive correlation between expression levels of SOX9 and BMI1 and a negative correlation between SOX9 and ARF in clinical samples. Taken together, our findings provide direct mechanistic evidence of the involvement of SOX9 in neoplastic pathobiology, particularly in colorectal cancer. PMID:22246670

  18. Oncogenes Activate an Autonomous Transcriptional Regulatory Circuit That Drives Glioblastoma.

    PubMed

    Singh, Dinesh K; Kollipara, Rahul K; Vemireddy, Vamsidara; Yang, Xiao-Li; Sun, Yuxiao; Regmi, Nanda; Klingler, Stefan; Hatanpaa, Kimmo J; Raisanen, Jack; Cho, Steve K; Sirasanagandla, Shyam; Nannepaga, Suraj; Piccirillo, Sara; Mashimo, Tomoyuki; Wang, Shan; Humphries, Caroline G; Mickey, Bruce; Maher, Elizabeth A; Zheng, Hongwu; Kim, Ryung S; Kittler, Ralf; Bachoo, Robert M

    2017-01-24

    Efforts to identify and target glioblastoma (GBM) drivers have primarily focused on receptor tyrosine kinases (RTKs). Clinical benefits, however, have been elusive. Here, we identify an SRY-related box 2 (SOX2) transcriptional regulatory network that is independent of upstream RTKs and capable of driving glioma-initiating cells. We identified oligodendrocyte lineage transcription factor 2 (OLIG2) and zinc-finger E-box binding homeobox 1 (ZEB1), which are frequently co-expressed irrespective of driver mutations, as potential SOX2 targets. In murine glioma models, we show that different combinations of tumor suppressor and oncogene mutations can activate Sox2, Olig2, and Zeb1 expression. We demonstrate that ectopic co-expression of the three transcription factors can transform tumor-suppressor-deficient astrocytes into glioma-initiating cells in the absence of an upstream RTK oncogene. Finally, we demonstrate that the transcriptional inhibitor mithramycin downregulates SOX2 and its target genes, resulting in markedly reduced proliferation of GBM cells in vivo.

  19. Systematic expression analysis of Hox genes at adulthood reveals novel patterns in the central nervous system.

    PubMed

    Hutlet, Bertrand; Theys, Nicolas; Coste, Cécile; Ahn, Marie-Thérèse; Doshishti-Agolli, Konstantin; Lizen, Benoît; Gofflot, Françoise

    2016-04-01

    Hox proteins are key regulators of animal development, providing positional identity and patterning information to cells along the rostrocaudal axis of the embryo. Although their embryonic expression and function are well characterized, their presence and biological importance in adulthood remains poorly investigated. We provide here the first detailed quantitative and neuroanatomical characterization of the expression of the 39 Hox genes in the adult mouse brain. Using RT-qPCR we determined the expression of 24 Hox genes mainly in the brainstem of the adult brain, with low expression of a few genes in the cerebellum and the forebrain. Using in situ hybridization (ISH) we have demonstrated that expression of Hox genes is maintained in territories derived from the early segmental Hox expression domains in the hindbrain. Indeed, we show that expression of genes belonging to paralogy groups PG2-8 is maintained in the hindbrain derivatives at adulthood. The spatial colinearity, which characterizes the early embryonic expression of Hox genes, is still observed in sequential antero-posterior boundaries of expression. Moreover, the main mossy and climbing fibres precerebellar nuclei express PG2-8 Hox genes according to their migration origins. Second, ISH confirms the presence of Hox gene transcripts in territories where they are not detected during development, suggesting neo-expression in these territories in adulthood. Within the forebrain, we have mapped Hoxb1, Hoxb3, Hoxb4, Hoxd3 and Hoxa5 expression in restricted areas of the sensory cerebral cortices as well as in specific thalamic relay nuclei. Our data thus suggest a requirement of Hox genes beyond their role of patterning genes, providing a new dimension to their functional relevance in the central nervous system.

  20. Human gene control by vital oncogenes: revisiting a theoretical model and its implications for targeted cancer therapy.

    PubMed

    Willis, Rudolph E

    2012-01-01

    An important assumption of our current understanding of the mechanisms of carcinogenesis has been the belief that clarification of the cancer process would inevitably reveal some of the crucial mechanisms of normal human gene regulation. Since the momentous work of Bishop and Varmus, both the molecular and the biochemical processes underlying the events in the development of cancer have become increasingly clear. The identification of cellular signaling pathways and the role of protein kinases in the events leading to gene activation have been critical to our understanding not only of normal cellular gene control mechanisms, but also have clarified some of the important molecular and biochemical events occurring within a cancer cell. We now know that oncogenes are dysfunctional proto-oncogenes and that dysfunctional tumor suppressor genes contribute to the cancer process. Furthermore, Weinstein and others have hypothesized the phenomenon of oncogene addiction as a distinct characteristic of the malignant cell. It can be assumed that cancer cells, indeed, become dependent on such vital oncogenes. The products of these vital oncogenes, such as c-myc, may well be the Achilles heel by which targeted molecular therapy may lead to truly personalized cancer therapy. The remaining problem is the need to introduce relevant molecular diagnostic tests such as genome microarray analysis and proteomic methods, especially protein kinase identification arrays, for each individual patient. Genome wide association studies on cancers with gene analysis of single nucleotide and other mutations in functional proto-oncogenes will, hopefully, identify dysfunctional proto-oncogenes and allow the development of more specific targeted drugs directed against the protein products of these vital oncogenes. In 1984 Willis proposed a molecular and biochemical model for eukaryotic gene regulation suggesting how proto-oncogenes might function within the normal cell. That model predicted the

  1. Comprehensive Expression Map of Transcription Regulators in the Adult Zebrafish Telencephalon Reveals Distinct Neurogenic Niches

    PubMed Central

    Diotel, Nicolas; Rodriguez Viales, Rebecca; Armant, Olivier; März, Martin; Ferg, Marco; Rastegar, Sepand; Strähle, Uwe

    2015-01-01

    The zebrafish has become a model to study adult vertebrate neurogenesis. In particular, the adult telencephalon has been an intensely studied structure in the zebrafish brain. Differential expression of transcriptional regulators (TRs) is a key feature of development and tissue homeostasis. Here we report an expression map of 1,202 TR genes in the telencephalon of adult zebrafish. Our results are summarized in a database with search and clustering functions to identify genes expressed in particular regions of the telencephalon. We classified 562 genes into 13 distinct patterns, including genes expressed in the proliferative zone. The remaining 640 genes displayed unique and complex patterns of expression and could thus not be grouped into distinct classes. The neurogenic ventricular regions express overlapping but distinct sets of TR genes, suggesting regional differences in the neurogenic niches in the telencephalon. In summary, the small telencephalon of the zebrafish shows a remarkable complexity in TR gene expression. The adult zebrafish telencephalon has become a model to study neurogenesis. We established the expression pattern of more than 1200 transcription regulators (TR) in the adult telencephalon. The neurogenic regions express overlapping but distinct sets of TR genes suggesting regional differences in the neurogenic potential. J. Comp. Neurol. 523:1202–1221, 2015. © 2015 Wiley Periodicals, Inc. PMID:25556858

  2. Stochastic Resonance Reveals “Pilot Light” Expression in Mammalian Genes

    PubMed Central

    Ptitsyn, Andrey

    2008-01-01

    Background Microarrays are widely used for estimation of expression of thousands of genes in a biological sample. The resolution ability of this method is limited by the background noise. Low expressed genes are detected with insufficient reliability and expression of many genes is never detected at all. Methodology/Principal Findings We have applied the principles of stochastic resonance to detect expression of genes from microarray signals below the background noise level. We report the periodic pattern detected in genes called “Absent” by traditional analysis. The pattern is consistent with expression of the conventionally detected genes and specific to the tissue of origin. This effect is corroborated by the analysis of oscillating gene expression in mouse (M.musculus) and yeast (S. cerevisae). Conclusion/Significance Most genes usually considered silent are in fact expressed at a very low level. Stochastic resonance can be applied to detect changes in expression pattern of low-expressed genes as well as for the validation of the probe performance in microarrays. PMID:18365000

  3. LEO1 is regulated by PRL-3 and mediates its oncogenic properties in acute myelogenous leukemia.

    PubMed

    Chong, Phyllis S Y; Zhou, Jianbiao; Cheong, Lip-Lee; Liu, Shaw-Cheng; Qian, Jingru; Guo, Tiannan; Sze, Siu Kwan; Zeng, Qi; Chng, Wee Joo

    2014-06-01

    PRL-3, an oncogenic dual-specificity phosphatase, is overexpressed in 50% of acute myelogenous leukemia (AML) and associated with poor survival. We found that stable expression of PRL-3 confers cytokine independence and growth advantage of AML cells. However, how PRL-3 mediates these functions in AML is not known. To comprehensively screen for PRL3-regulated proteins in AML, we performed SILAC-based quantitative proteomics analysis and discovered 398 significantly perturbed proteins after PRL-3 overexpression. We show that Leo1, a component of RNA polymerase II-associated factor (PAF) complex, is a novel and important mediator of PRL-3 oncogenic activities in AML. We described a novel mechanism where elevated PRL-3 protein increases JMJD2C histone demethylase occupancy on Leo1 promoter, thereby reducing the H3K9me3 repressive signals and promoting Leo1 gene expression. Furthermore, PRL-3 and Leo1 levels were positively associated in AML patient samples (N=24; P<0.01). On the other hand, inhibition of Leo1 reverses PRL-3 oncogenic phenotypes in AML. Loss of Leo1 leads to destabilization of the PAF complex and downregulation of SOX2 and SOX4, potent oncogenes in myeloid transformation. In conclusion, we identify an important and novel mechanism by which PRL-3 mediates its oncogenic function in AML.

  4. Viral Oncogenes, Noncoding RNAs, and RNA Splicing in Human Tumor Viruses

    PubMed Central

    Zheng, Zhi-Ming

    2010-01-01

    Viral oncogenes are responsible for oncogenesis resulting from persistent virus infection. Although different human tumor viruses express different viral oncogenes and induce different tumors, their oncoproteins often target similar sets of cellular tumor suppressors or signal pathways to immortalize and/or transform infected cells. Expression of the viral E6 and E7 oncogenes in papillomavirus, E1A and E1B oncogenes in adenovirus, large T and small t antigen in polyomavirus, and Tax oncogene in HTLV-1 are regulated by alternative RNA splicing. However, this regulation is only partially understood. DNA tumor viruses also encode noncoding RNAs, including viral microRNAs, that disturb normal cell functions. Among the determined viral microRNA precursors, EBV encodes 25 from two major clusters (BART and BHRF1), KSHV encodes 12 from a latent region, human polyomavirus MCV produce only one microRNA from the late region antisense to early transcripts, but HPVs appears to produce no viral microRNAs. PMID:21152115

  5. Transcriptome Sequencing Reveals Wide Expression Reprogramming of Basal and Unknown Genes in Leptospira biflexa Biofilms

    PubMed Central

    Spangenberg, Lucía; Lopes Bastos, Bruno; Graña, Martín; Vasconcelos, Larissa; Almeida, Áurea; Greif, Gonzalo; Robello, Carlos; Ristow, Paula

    2016-01-01

    ABSTRACT The genus Leptospira is composed of pathogenic and saprophytic spirochetes. Pathogenic Leptospira is the etiological agent of leptospirosis, a globally spread neglected disease. A key ecological feature of some pathogenic species is their ability to survive both within and outside the host. For most leptospires, the ability to persist outside the host is associated with biofilm formation, a most important bacterial strategy to face and overcome hostile environmental conditions. The architecture and biochemistry of leptospiral biofilms are rather well understood; however, the genetic program underpinning biofilm formation remains mostly unknown. In this work, we used the saprophyte Leptospira biflexa as a model organism to assess over- and underrepresented transcripts during the biofilm state, using transcriptome sequencing (RNA-seq) technology. Our results showed that some basal biological processes like DNA replication and cell division are downregulated in the mature biofilm. Additionally, we identified significant expression reprogramming for genes involved in motility, sugar/lipid metabolism, and iron scavenging, as well as for outer membrane-encoding genes. A careful manual annotation process allowed us to assign molecular functions to many previously uncharacterized genes that are probably involved in biofilm metabolism. We also provided evidence for the presence of small regulatory RNAs in this species. Finally, coexpression networks were reconstructed to pinpoint functionally related gene clusters that may explain how biofilm maintenance is regulated. Beyond elucidating some genetic aspects of biofilm formation, this work reveals a number of pathways whose functional dissection may impact our understanding of leptospiral biology, in particular how these organisms adapt to environmental changes. IMPORTANCE In this work, we describe the first transcriptome based on RNA-seq technology focused on studying transcriptional changes associated with biofilm

  6. Integrative analysis of lung development-cancer expression associations reveals the roles of signatures with inverse expression patterns.

    PubMed

    Zhang, Chunlong; Li, Chunquan; Xu, Yanjun; Feng, Li; Shang, Desi; Yang, Xinmiao; Han, Junwei; Sun, Zeguo; Li, Yixue; Li, Xia

    2015-05-01

    Recent studies have focused on exploring the associations between organ development and malignant tumors; however, the clinical relevance of the development signatures was inadequately addressed in lung cancer. In this study, we explored the associations between lung development and lung cancer progression by analyzing a total of two development and seven cancer datasets. We identified representative expression patterns (continuously up- and down-regulated) from development and cancer profiles, and inverse pattern associations were observed at both the gene and functional levels. Furthermore, we dissected the biological processes dominating the associations, and found that proliferation and immunity were respectively involved in the two inverse development-cancer expression patterns. Through sub-pathway analysis of the signatures with inverse expression patterns, we finally identified a 13-gene risk signature from the cell cycle sub-pathway, and evaluated its predictive performance for lung cancer patient clinical outcome using independent cohorts. Our findings indicated that the integrative analysis of development and cancer expression patterns provided a framework for identifying effective molecular signatures for clinical utility.

  7. Generation of fibrosarcomas in vivo by a retrovirus that expresses the normal B chain of platelet-derived growth factor and mimics the alternative splice pattern of the v-sis oncogene

    SciTech Connect

    Pech, M.; Gazit, A.; Arnstein, P.; Aaronson, S.A. )

    1989-04-01

    A retrovirus containing the entire human platelet-derived growth factor B-chain (PDGF-B) gene was constructed in order to investigate the in vivo biological activity of its encoded growth factor. When this virus was introduced into newborn mice, it reproducibly generated fibrosarcomas at the site of inoculation. Proviruses in each fibrosarcoma analyzed had lost 149 nucleotides downstream of the PDGF-B coding region. This deletion originated from an alternative or aberrant splice event that occurred within exon 7 of the PDGF-B gene and mimicked the v-sis oncogene. Thus, deletion of this region may be necessary for efficient retrovirus replication or for more potent transforming function. Evidence that the normal growth factor coding sequence was unaltered derived from RNase protection studies and immunoprecipitation analysis. Tumors were generally polyclonal but demonstrated clonal subpopulations. Moreover, tumor-derived cell lines became monoclonal within a few tissue culture passages and rapidly formed tumors in vivo. These findings argue that overexpression of the normal human PDGF-B gene product under retrovirus control can induce the fully malignant phenotype.

  8. Correlating chemical sensitivity and basal gene expression reveals mechanism of action | Office of Cancer Genomics

    Cancer.gov

    Changes in cellular gene expression in response to small-molecule or genetic perturbations have yielded signatures that can connect unknown mechanisms of action (MoA) to ones previously established. We hypothesized that differential basal gene expression could be correlated with patterns of small-molecule sensitivity across many cell lines to illuminate the actions of compounds whose MoA are unknown.

  9. Automated decoding of facial expressions reveals marked differences in children when telling antisocial versus prosocial lies.

    PubMed

    Zanette, Sarah; Gao, Xiaoqing; Brunet, Megan; Bartlett, Marian Stewart; Lee, Kang

    2016-10-01

    The current study used computer vision technology to examine the nonverbal facial expressions of children (6-11years old) telling antisocial and prosocial lies. Children in the antisocial lying group completed a temptation resistance paradigm where they were asked not to peek at a gift being wrapped for them. All children peeked at the gift and subsequently lied about their behavior. Children in the prosocial lying group were given an undesirable gift and asked if they liked it. All children lied about liking the gift. Nonverbal behavior was analyzed using the Computer Expression Recognition Toolbox (CERT), which employs the Facial Action Coding System (FACS), to automatically code children's facial expressions while lying. Using CERT, children's facial expressions during antisocial and prosocial lying were accurately and reliably differentiated significantly above chance-level accuracy. The basic expressions of emotion that distinguished antisocial lies from prosocial lies were joy and contempt. Children expressed joy more in prosocial lying than in antisocial lying. Girls showed more joy and less contempt compared with boys when they told prosocial lies. Boys showed more contempt when they told prosocial lies than when they told antisocial lies. The key action units (AUs) that differentiate children's antisocial and prosocial lies are blink/eye closure, lip pucker, and lip raise on the right side. Together, these findings indicate that children's facial expressions differ while telling antisocial versus prosocial lies. The reliability of CERT in detecting such differences in facial expression suggests the viability of using computer vision technology in deception research.

  10. Identical expression profiling of human and murine TIPE3 protein reveals links to its functions.

    PubMed

    Cui, Jian; Hao, Chunyan; Zhang, Wenqian; Shao, Jie; Zhang, Na; Zhang, Guizhong; Liu, Suxia

    2015-03-01

    Tumor necrosis factor-alpha-induced protein-8 like-3 (TNFAIP8L3, TIPE3) is a newly discovered member of TNFAIP8 family and regarded as a lipid second messenger transfer protein that promotes cancer. Yet the nature of the cells and tissues that express TIPE3 protein has not been determined. In this study, we examined TIPE3 expression in various murine and human tissues by immunohistochemistry and quantitative PCR. We found that TIPE3 expression was almost identical in most organs from human and mice. TIPE3 is a cytoplasmic protein expressed preferentially in epithelial-derived cells with secretory functions. Furthermore, TIPE3 protein is highly expressed in most human carcinoma cell lines. These results suggest that TIPE3 may play important roles in carcinogenesis and cell secretion.

  11. Identical Expression Profiling of Human and Murine TIPE3 Protein Reveals Links to Its Functions

    PubMed Central

    Cui, Jian; Hao, Chunyan; Zhang, Wenqian; Shao, Jie; Zhang, Na; Zhang, Guizhong

    2015-01-01

    Tumor necrosis factor-alpha-induced protein-8 like-3 (TNFAIP8L3, TIPE3) is a newly discovered member of TNFAIP8 family and regarded as a lipid second messenger transfer protein that promotes cancer. Yet the nature of the cells and tissues that express TIPE3 protein has not been determined. In this study, we examined TIPE3 expression in various murine and human tissues by immunohistochemistry and quantitative PCR. We found that TIPE3 expression was almost identical in most organs from human and mice. TIPE3 is a cytoplasmic protein expressed preferentially in epithelial-derived cells with secretory functions. Furthermore, TIPE3 protein is highly expressed in most human carcinoma cell lines. These results suggest that TIPE3 may play important roles in carcinogenesis and cell secretion. PMID:25479791

  12. Gene targeting study reveals unexpected expression of brain-expressed X-linked 2 in endocrine and tissue stem/progenitor cells in mice.

    PubMed

    Ito, Keiichi; Yamazaki, Satoshi; Yamamoto, Ryo; Tajima, Yoko; Yanagida, Ayaka; Kobayashi, Toshihiro; Kato-Itoh, Megumi; Kakuta, Shigeru; Iwakura, Yoichiro; Nakauchi, Hiromitsu; Kamiya, Akihide

    2014-10-24

    Identification of genes specifically expressed in stem/progenitor cells is an important issue in developmental and stem cell biology. Genome-wide gene expression analyses in liver cells performed in this study have revealed a strong expression of X-linked genes that include members of the brain-expressed X-linked (Bex) gene family in stem/progenitor cells. Bex family genes are expressed abundantly in the neural cells and have been suggested to play important roles in the development of nervous tissues. However, the physiological role of its individual members and the precise expression pattern outside the nervous system remain largely unknown. Here, we focused on Bex2 and examined its role and expression pattern by generating knock-in mice; the enhanced green fluorescence protein (EGFP) was inserted into the Bex2 locus. Bex2-deficient mice were viable and fertile under laboratory growth conditions showing no obvious phenotypic abnormalities. Through an immunohistochemical analysis and flow cytometry-based approach, we observed unique EGFP reporter expression patterns in endocrine and stem/progenitor cells of the liver, pyloric stomach, and hematopoietic system. Although Bex2 seems to play redundant roles in vivo, these results suggest the significance and potential applications of Bex2 in studies of endocrine and stem/progenitor cells.

  13. Evolution of the insect body plan as revealed by the Sex combs reduced expression pattern.

    PubMed

    Rogers, B T; Peterson, M D; Kaufman, T C

    1997-01-01

    The products of the HOM/Hox homeotic genes form a set of evolutionarily conserved transcription factors that control elaborate developmental processes and specify cell fates in many metazoans. We examined the expression of the ortholog of the homeotic gene Sex combs reduced (Scr) of Drosophila melanogaster in insects of three divergent orders: Hemiptera, Orthoptera and Thysanura. Our data reflect how the conservation and variation of Scr expression has affected the morphological evolution of insects. Whereas the anterior epidermal expression of Scr, in a small part of the posterior maxillary and all of the labial segment, is found to be in common among all four insect orders, the posterior (thoracic) expression domains vary. Unlike what is observed in flies, the Scr orthologs of other insects are not expressed broadly over the first thoracic segment, but are restricted to small patches. We show here that Scr is required for suppression of wings on the prothorax of Drosophila. Moreover, Scr expression at the dorsal base of the prothoracic limb in two other winged insects, crickets (Orthoptera) and milkweed bugs (Hemiptera), is consistent with Scr acting as a suppressor of prothoracic wings in these insects. Scr is also expressed in a small patch of cells near the basitarsal-tibial junction of milkweed bugs, precisely where a leg comb develops, suggesting that Scr promotes comb formation, as it does in Drosophila. Surprisingly, the dorsal prothoracic expression of Scr is also present in the primitively wingless firebrat (Thysanura) and the leg patch is seen in crickets, which have no comb. Mapping both gene expression patterns and morphological characters onto the insect phylogenetic tree demonstrates that in the cases of wing suppression and comb formation the appearance of expression of Scr in the prothorax apparently precedes these specific functions.

  14. Primary structure of the human fgr proto-oncogene product p55/sup c-fgr/

    SciTech Connect

    Katamine, S.; Notario, V.; Rao, C.D.; Miki, T.; Cheah, M.S.C.; Tronick, S.R.; Robbins, K.C.

    1988-01-01

    Normal human c-fgr cDNA clones were constructed by using normal peripheral blood mononuclear cell mRNA as a template. Nucleotide sequence analysis of two such clones revealed a 1,587-base-pair-long open reading frame which predicted the primary amino acid sequence of the c-fgr translational product. Homology of this protein with the v-fgr translational product stretched from codons 128 to 516, where 32 differences among 388 codons were observed. Sequence similarity with human c-src, c-yes, and fyn translations products began at amino acid position 76 of the predicted c-fgr protein and extended nearly to its C-terminus. In contrast, the stretch of 75 amino acids at the N-terminus demonstrated a greatly reduced degree of relatedness to these same proteins. To verify the deduced amino acid sequence, antibodies were prepared against peptides representing amino- and carboxy-terminal regions of the predicted c-fgr translational product. Both antibodies specifically recognized a 55-kilodalton protein expressed in COS-1 cells transfected with a c-fgr cDNA expression plasmid. Moreover, the same protein was immunoprecipitated from an Epstein-Barr virus-infected Burkitt's lymphoma cell line which expressed c-fgr mRNA but not in its uninfected fgr mRNA-negative counterpart. These findings identified the 55-kilodalton protein as the product of the human fgr proto-oncogene.

  15. Oncogenic KRAS activates an embryonic stem cell-like program in human colon cancer initiation.

    PubMed

    Le Rolle, Anne-France; Chiu, Thang K; Zeng, Zhaoshi; Shia, Jinru; Weiser, Martin R; Paty, Philip B; Chiu, Vi K

    2016-01-19

    Colorectal cancer is the third most frequently diagnosed cancer worldwide. Prevention of colorectal cancer initiation represents the most effective overall strategy to reduce its associated morbidity and mortality. Activating KRAS mutation (KRASmut) is the most prevalent oncogenic driver in colorectal cancer development, and KRASmut inhibition represents an unmet clinical need. We apply a systems-level approach to study the impact of KRASmut on stem cell signaling during human colon cancer initiation by performing gene set enrichment analysis on gene expression from human colon tissues. We find that KRASmut imposes the embryonic stem cell-like program during human colon cancer initiation from colon adenoma to stage I carcinoma. Expression of miR145, an embryonic SC program inhibitor, promotes cell lineage differentiation marker expression in KRASmut colon cancer cells and significantly suppresses their tumorigenicity. Our data support an in vivo plasticity model of human colon cancer initiation that merges the intrinsic stem cell properties of aberrant colon stem cells with the embryonic stem cell-like program induced by KRASmut to optimize malignant transformation. Inhibition of the embryonic SC-like program in KRASmut colon cancer cells reveals a novel therapeutic strategy to programmatically inhibit KRASmut tumors and prevent colon cancer.

  16. Gene expression profiling by mRNA array reveals different pattern in Chinese glioblastoma patients between Uygur and Han populations

    PubMed Central

    Liu, Liang; Xia, Haichen; Luan, Xinping; Dun, Zhiping; Zhu, Zhengquan; Dushan, Bieke; Li, Wenting

    2015-01-01

    Objective: To identify differentially expressed genes in Chinese glioblastoma patients of Uygur and Han populations, and investigate their potential clinical value for pathogenesis determination and progress prediction. Methods: Gene expression profiling was obtained from three patients of each Uygur and Han nationalities, respectively, by mRNA expression array. Data were processed by the GenomeStudio software and language R of the Lumi package, followed by GO (Gene Ontology) term and KEGG pathway annotation analysis by the Web Gestalt software. Results: The comparative analysis of genome-scale gene expression in glioblastomas revealed 1,475 differentially expressed genes, with 669 and 807 genes up-regulated and down-regulated, respectively. These included the STRC gene, which has two transcripts, one up-regulated and one down-regulated. GO term analysis suggested that 1,175 out of 1,475 key genes were involved in small GTPase mediated signal transduction, Ras protein signal transduction, bioprocess of neuronal response regulation, and central nervous system myelination. The KEGG pathway enrichment analysis showed that the differentially expressed genes were covered by 28 signaling pathways associated with tumorigenesis, including metabolic pathways, tumor suppressor pathways, MAP kinase signaling pathways, TGF-β signaling pathway, neurotrophin signaling pathways, and mTOR signaling pathway. Conclusion: The comparative study of gene expression profiling in glioblastomas between Uygur and Han nationalities revealed differentially expressed genes, whose functions and expression localization were analyzed by GO term analysis and KEGG pathway enrichment analysis. Different pathogenesis mechanisms were proposed for glioblastomas in Chinese patients of Uygur and Han nationalities from a molecular biology perspective. PMID:26309555

  17. Global Gene Expression and Focused Knockout Analysis Reveals Genes Associated with Fungal Fruiting Body Development in Neurospora crassa

    PubMed Central

    Wang, Zheng; Lopez-Giraldez, Francesc; Lehr, Nina; Farré, Marta; Common, Ralph; Trail, Frances

    2014-01-01

    Fungi can serve as highly tractable models for understanding genetic basis of sexual development in multicellular organisms. Applying a reverse-genetic approach to advance such a model, we used random and multitargeted primers to assay gene expression across perithecial development in Neurospora crassa. We found that functionally unclassified proteins accounted for most upregulated genes, whereas downregulated genes were enriched for diverse functions. Moreover, genes associated with developmental traits exhibited stage-specific peaks of expression. Expression increased significantly across sexual development for mating type gene mat a-1 and for mat A-1 specific pheromone precursor ccg-4. In addition, expression of a gene encoding a protein similar to zinc finger, stc1, was highly upregulated early in perithecial development, and a strain with a knockout of this gene exhibited arrest at the same developmental stage. A similar expression pattern was observed for genes in RNA silencing and signaling pathways, and strains with knockouts of these genes were also arrested at stages of perithecial development that paralleled their peak in expression. The observed stage specificity allowed us to correlate expression upregulation and developmental progression and to identify regulators of sexual development. Bayesian networks inferred from our expression data revealed previously known and new putative interactions between RNA silencing genes and pathways. Overall, our analysis provides a fine-scale transcriptomic landscape and novel inferences regarding the control of the multistage development process of sexual crossing and fruiting body development in N. crassa. PMID:24243796

  18. Single-cell nucleosome mapping reveals the molecular basis of gene expression heterogeneity.

    PubMed

    Small, Eliza C; Xi, Liqun; Wang, Ji-Ping; Widom, Jonathan; Licht, Jonathan D

    2014-06-17

    Nucleosomes, the basic unit of chromatin, have a critical role in the control of gene expression. Nucleosome positions have generally been determined by examining bulk populations of cells and then correlated with overall gene expression. Here, we describe a technique to determine nucleosome positioning in single cells by virtue of the ability of the nucleosome to protect DNA from GpC methylation. In the acid phosphatase inducible PHO5 gene, we find that there is significant cell-to-cell variation in nucleosome positions and shifts in nucleosome positioning correlate with changes in gene expression. However, nucleosome positioning is not absolute, and even with major shifts in gene expression, some cells fail to change nucleosome configuration. Mutations of the PHO5 promoter that introduce a poly(dA:dT) tract-stimulated gene expression under nonpermissive conditions led to shifts of positioned nucleosomes similar to induction of PHO5. By contrast, mutations that altered AA/TT/AT periodicity reduced gene expression upon PHO5 induction and stabilized nucleosomes in most cells, suggesting that enhanced nucleosome affinity for DNA antagonizes chromatin remodelers. Finally, we determined nucleosome positioning in two regions described as "fuzzy" or nucleosome-free when examined in a bulk assay. These regions consisted of distinct nucleosomes with a larger footprint for potential location and an increase population of cells lacking a nucleosome altogether. These data indicate an underlying complexity of nucleosome positioning that may contribute to the flexibility and heterogeneity of gene expression.

  19. Noncanonical role of Hox14 revealed by its expression patterns in lamprey and shark.

    PubMed

    Kuraku, Shigehiro; Takio, Yoko; Tamura, Koji; Aono, Hideaki; Meyer, Axel; Kuratani, Shigeru

    2008-05-06

    Hox genes are arranged in uninterrupted clusters in vertebrate genomes, and the nested patterns of their expression define spatial identities in multiple embryonic tissues. The ancestral Hox cluster of vertebrates has long been thought to consist of, maximally, 13 Hox genes. However, recently, Hox14 genes were discovered in three chordate lineages, the coelacanth, cartilaginous fishes, and amphioxus, but their expression patterns have not yet been analyzed. We isolated Hox14 cDNAs from the Japanese lamprey and cloudy catshark. These genes were not expressed in the central nervous systems, somites, or fin buds/folds but were expressed in a restricted cell population surrounding the hindgut. The lack of Hox14 expression in most of the embryonic axial elements, where nested Hox expressions define spatial identities, suggests a decoupling of Hox14 genes' regulation from the ancestral regulatory mechanism. The relaxation of preexisting constraint for collinear expression may have permitted the secondary losses of this Hox member in the tetrapod and teleost lineages.

  20. CRISPR Perturbation of Gene Expression Alters Bacterial Fitness under Stress and Reveals Underlying Epistatic Constraints.

    PubMed

    Otoupal, Peter B; Erickson, Keesha E; Escalas-Bordoy, Antoni; Chatterjee, Anushree

    2017-01-20

    The evolution of antibiotic resistance has engendered an impending global health crisis that necessitates a greater understanding of how resistance emerges. The impact of nongenetic factors and how they influence the evolution of resistance is a largely unexplored area of research. Here we present a novel application of CRISPR-Cas9 technology for investigating how gene expression governs the adaptive pathways available to bacteria during the evolution of resistance. We examine the impact of gene expression changes on bacterial adaptation by constructing a library of deactivated CRISPR-Cas9 synthetic devices to tune the expression of a set of stress-response genes in Escherichia coli. We show that artificially inducing perturbations in gene expression imparts significant synthetic control over fitness and growth during stress exposure. We present evidence that these impacts are reversible; strains with synthetically perturbed gene expression regained wild-type growth phenotypes upon stress removal, while maintaining divergent growth characteristics under stress. Furthermore, we demonstrate a prevailing trend toward negative epistatic interactions when multiple gene perturbations are combined simultaneously, thereby posing an intrinsic constraint on gene expression underlying adaptive trajectories. Together, these results emphasize how CRISPR-Cas9 can be employed to engineer gene expression changes that shape bacterial adaptation, and present a novel approach to synthetically control the evolution of antimicrobial resistance.

  1. Neurotoxic protein expression reveals connections between the circadian clock and mating behavior in Drosophila

    PubMed Central

    Kadener, Sebastian; Villella, Adriana; Kula, Elzbieta; Palm, Kristyna; Pyza, Elzbieta; Botas, Juan; Hall, Jeffrey C.; Rosbash, Michael

    2006-01-01

    To investigate the functions of circadian neurons, we added two strategies to the standard Drosophila behavioral genetics repertoire. The first was to express a polyglutamine-expanded neurotoxic protein (MJDtr78Q; MJD, Machado–Joseph disease) in the major timeless (tim)-expressing cells of the adult brain. These Tim-MJD flies were viable, in contrast to the use of cell-death gene expression for tim neuron inactivation. Moreover, they were more arrhythmic than flies expressing other neurotoxins and had low but detectable tim mRNA levels. The second extended standard microarray technology from fly heads to dissected fly brains. By combining the two approaches, we identified a population of Tim-MJD-affected mRNAs. Some had been previously identified as sex-specific and relevant to courtship, including mRNAs localized to brain-proximal fat-body tissue and brain courtship centers. Finally, we found a decrease in the number of neurons that expressed male-specific forms of the fruitless protein in the laterodorsal region of the brain. The decrease was not a consequence of toxic protein expression within these specialized cells but a likely effect of communication with neighboring TIM-expressing neurons. The data suggest a functional interaction between adjacent circadian and mating circuits within the fly brain, as well as an interaction between circadian circuits and brain-proximal fat body. PMID:16938865

  2. Gene expression during normal and malignant differentiation

    SciTech Connect

    Andersson, L.C.; Gahmberg, C.G.; Ekblom, P.

    1985-01-01

    This book contains 18 selections. Some of the titles are: Exploring Carcinogenesis with Retroviral and Cellular Oncogenes; Retroviruses, Oncogenes and Evolution; HTLV and Human Neoplasi; Modes of Activation of cMyc Oncogene in B and T Lymphoid Tumors; The Structure and Function of the Epidermal Growth Factor Receptor: Its Relationship to the Protein Product of the V-ERB-B Oncogene; and Expression of Human Retrovirus Genes in Normal and Neoplastic Epithelial Cells.

  3. An analysis of the expression of cyclophilin C reveals tissue restriction and an intriguing pattern in the mouse kidney.

    PubMed Central

    Friedman, J.; Weissman, I.; Friedman, J.; Alpert, S.

    1994-01-01

    Cyclophilin C (cyp C) is a cyclosporin A (CsA) binding protein originally isolated from a mouse bone marrow stromal cell line. We have compared the expression patterns of the mammalian cyclophilins A, B, and C in mouse tissues using in situ hybridization. These studies reveal that cyp C is expressed in a restricted subset of tissues including mouse ovary, testis, bone marrow, and kidney. Within the kidney, cyp C is highly expressed in a narrow zone in the outer medulla. Using monoclonal antibodies reactive against cyp C, we find that the kidney cells expressing cyp C correspond to the S3 segment of the nephron. The S3 segment has been shown to sustain histopathological damage from high dosages of CsA, raising the possibility that cyp C may be involved in mediating this damage. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:8203464

  4. The roles of oncogenic miRNAs and their therapeutic importance in breast cancer.

    PubMed

    O'Bryan, Samia; Dong, Shengli; Mathis, J Michael; Alahari, Suresh K

    2017-02-01

    Since the discovery of tumour suppressive miRNA in 2002, the dysregulation of miRNAs was implicated in many cancers, exhibiting both tumour suppressive and oncogenic roles. Dysregulation of miRNAs was found to be involved in the initiation of oncogenesis, as well as the progression, invasion and metastasis of cancers. While normal miRNA inhibitory functions help regulate gene expression in the cell, oncogenic miRNA, when dysregulated can lead to suppression of critical pathways that control apoptosis, cell cycle progression, growth and proliferation. This suppression allows for the upregulation of pro-oncogenic factors that drive cell survival, growth and proliferation. Due to emerging discoveries, oncogenic miRNAs are proving to be a critical component in cancers, such as breast cancer, and may provide novel avenues for cancer treatment. In this article, we discuss the roles of the most studied oncogenic miRNAs in breast cancer including clusters and families involved as well as the less studied and recently discovered oncogenic miRNAs. These miRNAs provide valuable information into the complexity of regulatory elements affected by their overexpression and the overall impact in the progression of breast cancer. Also, identifying miRNAs causing or leading to resistance or sensitivity to current anti-cancer drugs prior to treatment may lead to an improvement in treatment selection and overall patient response. This review summarizes known and recently discovered miRNAs in literature found to have oncogenic roles in breast cancer initiation and the progression, invasion and metastasis of the disease.

  5. Gene expression analysis reveals the dysregulation of immune and metabolic pathways in Alzheimer's disease

    PubMed Central

    Li, Zhiyan; Xu, Panpan; Yao, Lifen

    2016-01-01

    In recent years, several pathway analyses of genome-wide association studies reported the involvement of metabolic and immune pathways in Alzheimer's disease (AD). Until now, the exact mechanisms of these pathways in AD are still unclear. Here, we conducted a pathway analysis of a whole genome AD case-control expression dataset (n=41, 25 AD cases and 16 controls) from the human temporal cortex tissue. Using the differently expressed AD genes, we identified significant KEGG pathways related to metabolism and immune processes. Using the up- and down- regulated AD gene list, we further found up-regulated AD gene were significantly enriched in immune and metabolic pathways. We further compare the immune and metabolic KEGG pathways from the expression dataset with those from previous GWAS datasets, and found that most of these pathways are shared in both GWAS and expression datasets. PMID:27732949

  6. EXPRESSION PROFILING OF FIVE RAT STRAINS REVEAL TRANSCRIPTIONAL MODES IN THE ANTIGEN PROCESSING PATHWAY

    EPA Science Inventory

    Comparative gene expression profiling of rat strains with genetic predisposition to diverse cardiovascular diseases can help decode the transcriptional program that governs cellular behavior. We hypothesized that co-transcribed, intra-pathway, functionally coherent genes can be r...

  7. Metastatic Pancreatic Cancer Is Dependent on Oncogenic Kras in Mice

    PubMed Central

    Collins, Meredith A.; Brisset, Jean-Christophe; Zhang, Yaqing; Bednar, Filip; Pierre, Josette; Heist, Kevin A.; Galbán, Craig J.; Galbán, Stefanie; di Magliano, Marina Pasca

    2012-01-01

    Pancreatic cancer is one of the deadliest human malignancies, and its prognosis has not improved over the past 40 years. Mouse models that spontaneously develop pancreatic adenocarcinoma and mimic the progression of the human disease are emerging as a new tool to investigate the basic biology of this disease and identify potential therapeutic targets. Here, we describe a new model of metastatic pancreatic adenocarcinoma based on pancreas-specific, inducible and reversible expression of an oncogenic form of Kras, together with pancreas-specific expression of a mutant form of the tumor suppressor p53. Using high-resolution magnetic resonance imaging to follow individual animals in longitudinal studies, we show that both primary and metastatic lesions depend on continuous Kras activity for their maintenance. However, re-activation of Kras* following prolonged inactivation leads to rapid tumor relapse, raising the concern that Kras*-resistance might eventually be acquired. Thus, our data identifies Kras* as a key oncogene in pancreatic cancer maintenance, but raises the possibility of acquired resistance should Kras inhibitors become available for use in pancreatic cancer. PMID:23226501

  8. Eukaryotic Elongation Factor 2 Kinase Activity Is Controlled by Multiple Inputs from Oncogenic Signaling

    PubMed Central

    Wang, Xuemin; Regufe da Mota, Sergio; Liu, Rui; Moore, Claire E.; Xie, Jianling; Lanucara, Francesco; Agarwala, Usha; Pyr dit Ruys, Sébastien; Vertommen, Didier; Rider, Mark H.; Eyers, Claire E.

    2014-01-01

    Eukaryotic elongation factor 2 kinase (eEF2K), an atypical calmodulin-dependent protein kinase, phosphorylates and inhibits eEF2, slowing down translation elongation. eEF2K contains an N-terminal catalytic domain, a C-terminal α-helical region and a linker containing several regulatory phosphorylation sites. eEF2K is expressed at high levels in certain cancers, where it may act to help cell survival, e.g., during nutrient starvation. However, it is a negative regulator of protein synthesis and thus cell growth, suggesting that cancer cells may possess mechanisms to inhibit eEF2K under good growth conditions, to allow protein synthesis to proceed. We show here that the mTORC1 pathway and the oncogenic Ras/Raf/MEK/extracellular signal-regulated kinase (ERK) pathway cooperate to restrict eEF2K activity. We identify multiple sites in eEF2K whose phosphorylation is regulated by mTORC1 and/or ERK, including new ones in the linker region. We demonstrate that certain sites are phosphorylated directly by mTOR or ERK. Our data reveal that glycogen synthase kinase 3 signaling also regulates eEF2 phosphorylation. In addition, we show that phosphorylation sites remote from the N-terminal calmodulin-binding motif regulate the phosphorylation of N-terminal sites that control CaM binding. Mutations in the former sites, which occur in cancer cells, cause the activation of eEF2K. eEF2K is thus regulated by a network of oncogenic signaling pathways. PMID:25182533

  9. RNA sequencing reveals small RNAs differentially expressed between incipient Japanese threespine sticklebacks

    PubMed Central

    2013-01-01

    Background Non-coding small RNAs, ranging from 20 to 30 nucleotides in length, mediate the regulation of gene expression and play important roles in many biological processes. One class of small RNAs, microRNAs (miRNAs), are highly conserved across taxa and mediate the regulation of the chromatin state and the post-transcriptional regulation of messenger RNA (mRNA). Another class of small RNAs is the Piwi-interacting RNAs, which play important roles in the silencing of transposons and other functional genes. Although the biological functions of the different small RNAs have been elucidated in several laboratory animals, little is known regarding naturally occurring variation in small RNA transcriptomes among closely related species. Results We employed next-generation sequencing technology to compare the expression profiles of brain small RNAs between sympatric species of the Japanese threespine stickleback (Gasterosteus aculeatus). We identified several small RNAs that were differentially expressed between sympatric Pacific Ocean and Japan Sea sticklebacks. Potential targets of several small RNAs were identified as repetitive sequences. Female-biased miRNA expression from the old X chromosome was also observed, and it was attributed to the degeneration of the Y chromosome. Conclusions Our results suggest that expression patterns of small RNA can differ between incipient species and may be a potential mechanism underlying differential mRNA expression and transposon activity. PMID:23547919

  10. cDNA-AFLP transcriptional profiling reveals genes expressed during flower development in Oncidium Milliongolds.

    PubMed

    Qian, X; Gong, M J; Wang, C X; Tian, M

    2014-02-21

    The flower developmental process, which is crucial to the whole lifecycle of higher plants, is influenced by both environmental and endogenous factors. The genus Oncidium is commercially important for cut flower and houseplant industry and is ideal for flower development studies. Using cDNA-amplified restriction fragment length polymorphism analysis, we profiled transcripts that are differentially expressed during flower development of Oncidium Milliongolds. A total of 15,960 transcript-derived fragments were generated, with 114 primer sets. Of these, 1248 were sequenced, producing 993 readable sequences. BLASTX/N analysis showed that 833 of the 993 transcripts showed homology to genes in the NCBI databases, exhibiting functions involved in various processes, such as signal transduction, energy conversion, metabolism, and gene expression regulation. The full-length mRNAs of SUCROSE SYNTHASE 1 (SUS1) and LEAFY (LFY) were cloned, and their expression patterns were characterized. The results showed that the expression levels of SUS1 and LFY were similar during flower development. To confirm the function of SUS1 in flower buds, carbohydrate content and sucrose synthase activity were determined. The results showed that changes in sucrose content and sucrose synthase activity reflected SUS1 expression levels. Collectively, these results indicate that SUS1 influences flower development by regulating LFY expression levels through changing the sucrose content of flower buds.

  11. A novel method testing the ability to imitate composite emotional expressions reveals an association with empathy.

    PubMed

    Williams, Justin H G; Nicolson, Andrew T A; Clephan, Katie J; de Grauw, Haro; Perrett, David I

    2013-01-01

    Social communication relies on intentional control of emotional expression. Its variability across cultures suggests important roles for imitation in developing control over enactment of subtly different facial expressions and therefore skills in emotional communication. Both empathy and the imitation of an emotionally communicative expression may rely on a capacity to share both the experience of an emotion and the intention or motor plan associated with its expression. Therefore, we predicted that facial imitation ability would correlate with empathic traits. We built arrays of visual stimuli by systematically blending three basic emotional expressions in controlled proportions. Raters then assessed accuracy of imitation by reconstructing the same arrays using photographs of participants' attempts at imitations of the stimuli. Accuracy was measured as the mean proximity of the participant photographs to the target stimuli in the array. Levels of performance were high, and rating was highly reliable. More empathic participants, as measured by the empathy quotient (EQ), were better facial imitators and, in particular, performed better on the more complex, blended stimuli. This preliminary study offers a simple method for the measurement of facial imitation accuracy and supports the hypothesis that empathic functioning may utilise motor control mechanisms which are also used for emotional expression.

  12. A Novel Method Testing the Ability to Imitate Composite Emotional Expressions Reveals an Association with Empathy

    PubMed Central

    Williams, Justin H. G.; Nicolson, Andrew T. A.; Clephan, Katie J.; de Grauw, Haro; Perrett, David I.

    2013-01-01

    Social communication relies on intentional control of emotional expression. Its variability across cultures suggests important roles for imitation in developing control over enactment of subtly different facial expressions and therefore skills in emotional communication. Both empathy and the imitation of an emotionally communicative expression may rely on a capacity to share both the experience of an emotion and the intention or motor plan associated with its expression. Therefore, we predicted that facial imitation ability would correlate with empathic traits. We built arrays of visual stimuli by systematically blending three basic emotional expressions in controlled proportions. Raters then assessed accuracy of imitation by reconstructing the same arrays using photographs of participants’ attempts at imitations of the stimuli. Accuracy was measured as the mean proximity of the participant photographs to the target stimuli in the array. Levels of performance were high, and rating was highly reliable. More empathic participants, as measured by the empathy quotient (EQ), were better facial imitators and, in particular, performed better on the more complex, blended stimuli. This preliminary study offers a simple method for the measurement of facial imitation accuracy and supports the hypothesis that empathic functioning may utilise motor control mechanisms which are also used for emotional expression. PMID:23626756

  13. Serial bone marrow transplantation reveals in vivo expression of the pCLPG retroviral vector

    PubMed Central

    2010-01-01

    Background Gene therapy in the hematopoietic system remains promising, though certain aspects of vector design, such as transcriptional control elements, continue to be studied. Our group has developed a retroviral vector where transgene expression is controlled by p53 with the intention of harnessing the dynamic and inducible nature of this tumor suppressor and transcription factor. We present here a test of in vivo expression provided by the p53-responsive vector, pCLPG. For this, we used a model of serial transplantation of transduced bone marrow cells. Results We observed, by flow cytometry, that the eGFP transgene was expressed at higher levels when the pCLPG vector was used as compared to the parental pCL retrovirus, where expression is directed by the native MoMLV LTR. Expression from the pCLPG vector was longer lasting, but did decay along with each sequential transplant. The detection of eGFP-positive cells containing either vector was successful only in the bone marrow compartment and was not observed in peripheral blood, spleen or thymus. Conclusions These findings indicate that the p53-responsive pCLPG retrovirus did offer expression in vivo and at a level that surpassed the non-modified, parental pCL vector. Our results indicate that the pCLPG platform may provide some advantages when applied in the hematopoietic system. PMID:20096105

  14. Gene expression profiling of craniofacial fibrous dysplasia reveals ADAMTS2 overexpression as a potential marker.

    PubMed

    Zhou, Shang-Hui; Yang, Wen-Jun; Liu, Sheng-Wen; Li, Jiang; Zhang, Chun-Ye; Zhu, Yun; Zhang, Chen-Ping

    2014-01-01

    Fibrous dysplasia (FD) as an abnormal bone growth is one of the common fibro-osseous leasions (FOL) in oral and maxillofacial region, however, its etiology still remains unclear. Here, we performed gene expression profiling of FD using microarray analysis to explore the key molecule events in FD development, and develop potential diagnostic markers or therapeutic targets for FD. We found that 1,881 genes exhibited differential expression with more than two-fold changes in FD compared to normal bone tissues, including 1,200 upregulated genes and 681 downregulated genes. Pathway analysis indicated that obviously activated pathways are Ribosome and ECM-receptor interaction pathways; downregulated pathways are "Hepatitis C" and "cancer" signaling pathways. We further validated the expression of ADAMTS2, one of most differentiated expressed genes, by Immunohistochemistry (IHC) in 40 of FD cases. Results showed that ADAMTS2 was significantly overexpressed in FD tissues, but rarely expressed in normal bone tissues, suggesting that ADAMTS2 could be a potential biomarker for FD. Thus, this study uncovered differentially expressed candidate genes in FD, which provides pilot data for understanding FD pathogenesis, and developing novel biomarkers for diagnosis and targeting of FD.

  15. A reporter mouse reveals lineage-specific and heterogeneous expression of IRF8 during lymphoid and myeloid cell differentiation1

    PubMed Central

    Wang, Hongsheng; Yan, Ming; Sun, Jiafang; Jain, Shweta; Yoshimi, Ryusuke; Abolfath, Sanaz Momben; Ozato, Keiko; Coleman, William G.; Ng, Ashley P.; Metcalf, Donald; DiRago, Ladina; Nutt, Stephen L.; Morse, Herbert C.

    2014-01-01

    The interferon regulatory factor family member 8 (IRF8) regulates differentiation of lymphoid and myeloid lineage cells by promoting or suppressing lineage-specific genes. How IRF8 promotes hematopoietic progenitors to commit to one lineage while preventing the development of alternative lineages is not known. Here we report an IRF8-EGFP fusion protein reporter mouse that revealed previously unrecognized patterns of IRF8 expression. Differentiation of hematopoietic stem cells into oligopotent progenitors is associated with progressive increases in IRF8-EGFP expression. However, significant induction of IRF8-EGFP is found in granulocyte-myeloid progenitors (GMPs) and the common lymphoid progenitors (CLPs) but not the megakaryocytic-erythroid progenitors. Surprisingly, IRF8-EGFP identifies three subsets of the seemingly homogeneous GMPs with an intermediate level of expression of EGFP defining bipotent progenitors that differentiation into either EGFPhi monocytic progenitors or EGFPlo granulocytic progenitors. Also surprisingly, IRF8-EGFP revealed a highly heterogeneous pre-pro-B population with a fluorescence intensity ranging from background to 4 orders above background. Interestingly, IRF8-EGFP readily distinguishes true B cell-committed (EGFPint) from those that are non-committed. Moreover, dendritic cell progenitors expressed extremely high levels of IRF8-EGFP. Taken together, the IRF8-EGFP reporter revealed previously unrecognized subsets with distinct developmental potentials in phenotypically well-defined oligopotent progenitors, providing new insights into the dynamic heterogeneity of developing hematopoietic progenitors. PMID:25024380

  16. Dissecting the signaling pathways associated with the oncogenic activity of MLK3 P252H mutation

    PubMed Central

    2014-01-01

    Background MLK3 gene mutations were described to occur in about 20% of microsatellite unstable gastrointestinal cancers and to harbor oncogenic activity. In particular, mutation P252H, located in the kinase domain, was found to have a strong transforming potential, and to promote the growth of highly invasive tumors when subcutaneously injected in nude mice. Nevertheless, the molecular mechanism underlying the oncogenic activity of P252H mutant remained elusive. Methods In this work, we performed Illumina Whole Genome arrays on three biological replicas of human HEK293 cells stably transfected with the wild-type MLK3, the P252H mutation and with the empty vector (Mock) in order to identify the putative signaling pathways associated with P252H mutation. Results Our microarray results showed that mutant MLK3 deregulates several important colorectal cancer- associated signaling pathways such as WNT, MAPK, NOTCH, TGF-beta and p53, helping to narrow down the number of potential MLK3 targets responsible for its oncogenic effects. A more detailed analysis of the alterations affecting the WNT signaling pathway revealed a down-regulation of molecules involved in the canonical pathway, such as DVL2, LEF1, CCND1 and c-Myc, and an up-regulation of DKK, a well-known negative regulator of canonical WNT signaling, in MLK3 mutant cells. Additionally, FZD6 and FZD10 genes, known to act as negative regulators of the canonical WNT signaling cascade and as positive regulators of the planar cell polarity (PCP) pathway, a non-canonic WNT pathway, were found to be up-regulated in P252H cells. Conclusion The results provide an overall view of the expression profile associated with mutant MLK3, and they support the functional role of mutant MLK3 by showing a deregulation of several signaling pathways known to play important roles in the development and progression of colorectal cancer. The results also suggest that mutant MLK3 may be a novel modulator of WNT signaling, and pinpoint the

  17. The RUNX Genes as Conditional Oncogenes: Insights from Retroviral Targeting and Mouse Models.

    PubMed

    Neil, James C; Gilroy, Kathryn; Borland, Gillian; Hay, Jodie; Terry, Anne; Kilbey, Anna

    2017-01-01

    The observation that the Runx genes act as targets for transcriptional activation by retroviral insertion identified a new family of dominant oncogenes. However, it is now clear that Runx genes are 'conditional' oncogenes whose over-expression is growth inhibitory unless accompanied by another event such as concomitant over-expression of MYC or loss of p53 function. Remarkably, while the oncogenic activities of either MYC or RUNX over-expression are suppressed while p53 is intact, the combination of both neutralises p53 tumour suppression in vivo by as yet unknown mechanisms. Moreover, there is emerging evidence that endogenous, basal RUNX activity is important to maintain the viability and proliferation of MYC-driven lymphoma cells. There is also growing evidence that the human RUNX genes play a similar conditional oncogenic role and are selected for over-expression in end-stage cancers of multiple types. Paradoxically, reduced RUNX activity can also predispose to cell immortalisation and transformation, particularly by mutant Ras. These apparently conflicting observations may be reconciled in a stage-specific model of RUNX involvement in cancer. A question that has yet to be fully addressed is the extent to which the three Runx genes are functionally redundant in cancer promotion and suppression.

  18. Resistance to oncogenic transformation in revertant R1 of human ras-transformed NIH 3T3 cells

    SciTech Connect

    Kuzumaki, N.; Ogiso, Y.; Oda, A.; Fujita, H.; Suzuki, H.; Sato, C.; Mullauer, L.

    1989-05-01

    A flat revertant, R1, was isolated from human activated c-Ha-ras-1 (hu-ac-Ha-ras) gene-transformed NIH 3T3 cells (EJ-NIH 3T3) treated with mutagens. R1 contained unchanged transfected hu-ac-Ha-ras DNA and expressed high levels of hu-ac-Ha-ras-specific mRNA and p21 protein. Transfection experiments revealed that NIH 3T3 cells could be transformed by DNA from R1 cells but R1 cells could not be retransformed by Kirsten sarcoma virus, DNA from EJ-NIH 3T3 cells, hu-ac-Ha-ras, v-src, v-mos, simian virus 40 large T antigen, or polyomavirus middle T antigen. Somatic cell hybridization studies showed that R1 was not retransformed by fusion with NIH 3T3 cells and suppressed anchorage independence of EJ-NIH 3T3 and hu-ac-Ha-ras gene-transformed rat W31 cells in soft agar. These results suggest that the reversion and resistance to several oncogenes in R1 is due n not to cellular defects in the production of the transformed phenotype but rather to enhancement of cellular mechanisms that suppress oncogenic transformation.

  19. Distinct growth factor-induced dynamic mass redistribution (DMR) profiles for monitoring oncogenic signaling pathways in various cancer cells.

    PubMed

    Du, Yuhong; Li, Zijian; Li, Lian; Chen, Zhuo Georgia; Sun, Shi-Yong; Chen, Peifang; Shin, Dong M; Khuri, Fadlo R; Fu, Haian

    2009-01-01

    Targeting dysregulated signaling pathways in tumors has led to the development of a novel class of signal transduction inhibitors, including inhibitors of the epidermal growth factor (EGF) receptor (EGFR). To dissect oncogenic pathways, identify key pathway determinants, and evaluate the efficacy of targeted agents, it is vital to develop technologies that allow the detection of temporal signaling events under physiological conditions. Here we report the application of a label-free optical biosensor to reveal the rapid response of cancer cells to EGF, expressed as a dynamic mass redistribution (DMR) signal. In response to EGF, squamous cell carcinoma of the head and neck cells exhibited a rapid rise in DMR signal, whereas lung adenocarcinoma cells showed a biphasic DMR profile, suggesting a cell type-dependent DMR response. Pharmacological studies suggested the importance of EGFR and the phosphatidylinositol-3 kinase pathway in mediating the EGF-induced DMR response. The defined DMR signatures offer a simple yet sensitive tool for evaluating EGFR-targeted agents, as shown with gefitinib and erlotinib. The assay can also be used for cell-based high-throughput screening of EGF pathway inhibitors, as demonstrated by its robust performance in a 384-well plate format (Z' > 0.5). This technology is applicable to other oncogenic pathways for the discovery of novel therapeutic agents for the treatment of various cancers.

  20. Analysis of gene expression profiles reveals novel correlations with the clinical course of colorectal cancer.

    PubMed

    Cavalieri, Duccio; Dolara, Piero; Mini, Enrico; Luceri, Cristina; Castagnini, Cinzia; Toti, Simona; Maciag, Karolina; De Filippo, Carlotta; Nobili, Stefania; Morganti, Maria; Napoli, Cristina; Tonini, Giulia; Baccini, Michela; Biggeri, Annibale; Tonelli, Francesco; Valanzano, Rosa; Orlando, Claudio; Gelmini, Stefania; Cianchi, Fabio; Messerini, Luca; Luzzatto, Lucio

    2007-01-01

    In order to discover potential markers of prognosis in colorectal cancer (CRC) we have determined gene expression profiles, using cDNA microarrays in CRC samples obtained from 19 patients in Dukes stages C and D, with favorable clinical course (Dukes C patients, survival >5 years after surgery, group A, n=7) or unfavorable clinical course (Dukes stage C and D patients, survival <5 years after surgery, group B, n=12). Gene expression was measured in RNA from each tumor, using a pool of equal amounts of RNA from all tumors as a reference. To identify and rank differentially expressed genes we used three different analytical methods: (i) Significance Analysis of Microarrays (SAM), (ii) Cox's Proportional Hazard Model, and (iii) Trend Filter (a mathematical method for the assessment of numerical trends). The level of expression of a gene in an individual tumor was regarded as of interest when that gene was identified as differentially expressed by at least two of these three methods. By these stringent criteria we identified eight genes (ITGB2, MRPS11, NPR1, TXNL2, PHF10, PRSS8, KCNK3, JAK3) that were correlated with prolonged survival after surgery. Pathway analysis showed that patients with favorable prognosis had several activated metabolic pathways (carbon metabolism, transcription, amino acid and nitrogen metabolism, signaling and fibroblast growth factor receptor pathways). To further validate individual gene expression findings, the RNA level of each gene identified as a marker with microarrays was measured by real-time RT-PCR in CRC samples from an independent group of 55 patients. In this set of patients the Cox Proportional Hazard Model analysis demonstrated a significant association between increased patient survival and low expression of ITGB2 (p = 0.011) and NPR1 (p = 0.023) genes.

  1. Expression of the Retrotransposon Helena Reveals a Complex Pattern of TE Deregulation in Drosophila Hybrids

    PubMed Central

    Romero-Soriano, Valèria; Garcia Guerreiro, Maria Pilar

    2016-01-01

    Transposable elements (TEs), repeated mobile sequences, are ubiquitous in the eukaryotic kingdom. Their mobilizing capacity confers on them a high mutagenic potential, which must be strongly regulated to guarantee genome stability. In the Drosophila germline, a small RNA-mediated silencing system, the piRNA (Piwi-interacting RNA) pathway, is the main responsible TE regulating mechanism, but some stressful conditions can destabilize it. For instance, during interspecific hybridization, genomic stress caused by the shock of two different genomes can lead, in both animals and plants, to higher transposition rates. A recent study in D. buzatii—D. koepferae hybrids detected mobilization of 28 TEs, yet little is known about the molecular mechanisms explaining this transposition release. We have characterized one of the mobilized TEs, the retrotransposon Helena, and used quantitative expression to assess whether its high transposition rates in hybrids are preceded by increased expression. We have also localized Helena expression in the gonads to see if cellular expression patterns have changed in the hybrids. To give more insight into changes in TE regulation in hybrids, we analysed Helena-specific piRNA populations of hybrids and parental species. Helena expression is not globally altered in somatic tissues, but male and female gonads have different patterns of deregulation. In testes, Helena is repressed in F1, increasing then its expression up to parental values. This is linked with a mislocation of Helena transcripts along with an increase of their specific piRNA levels. Ovaries have additive levels of Helena expression, but the ping-pong cycle efficiency seems to be reduced in F1 hybrids. This could be at the origin of new Helena insertions in hybrids, which would be transmitted to F1 hybrid female progeny. PMID:26812285

  2. Single-cell gene expression analyses of cellular reprogramming reveal a stochastic early and hierarchic late phase

    PubMed Central

    Buganim, Yosef; Faddah, Dina A.; Cheng, Albert W.; Itskovich, Elena; Markoulaki, Styliani; Ganz, Kibibi; Klemm, Sandy L.; van Oudenaarden, Alexander; Jaenisch, Rudolf

    2012-01-01

    During cellular reprogramming only a small fraction of cells become induced pluripotent stem cells (iPSCs). Previous analyses of gene expression during reprogramming were based on populations of cells, impeding single-cell level identification of reprogramming events. We utilized two gene expression technologies to profile 48 genes in single cells at various stages during the reprogramming process. Analysis of early stages revealed considerable variation in gene expression between cells in contrast to late stages. Expression of Esrrb, Utf1, Lin28, and Dppa2 is a better predictor for cells to progress into iPSCs than expression of Fbxo15, Fgf4, and Oct4 previously suggested to be reprogramming markers. Stochastic gene expression early in reprogramming is followed by a late hierarchical phase with Sox2 being the upstream factor in a gene expression hierarchy. Finally, downstream factors derived from the late phase, which do not include Oct4, Sox2, Klf4, c-Myc and Nanog, can activate the pluripotency circuitry. PMID:22980981

  3. Major heat shock protein Hsp72 controls oncogene-induced senescence.

    PubMed

    Sherman, Michael

    2010-06-01

    Various heat shock proteins, including Hsp72, are strongly upregulated in cancers, but their significance for tumor emergence and growth is poorly understood. Here we review recent data from several labs to indicate that Hsps, including Hsp72, are critical for growth of transformed but not normal cells. By manipulating expression and activity of Hsp72 and several oncogenes, it was shown that Hsp72 suppresses oncogene-induced senescence, thus allowing proliferation of cancer cells. Importantly, Hsp72 is able to suppress both p53-dependent and p53-independent senescence pathways. We propose that targeting Hsp72 may be a promising approach toward development of novel cancer therapies.

  4. Single-Cell Expression Profiling Reveals a Dynamic State of Cardiac Precursor Cells in the Early Mouse Embryo.

    PubMed

    Kokkinopoulos, Ioannis; Ishida, Hidekazu; Saba, Rie; Ruchaya, Prashant; Cabrera, Claudia; Struebig, Monika; Barnes, Michael; Terry, Anna; Kaneko, Masahiro; Shintani, Yasunori; Coppen, Steven; Shiratori, Hidetaka; Ameen, Torath; Mein, Charles; Hamada, Hiroshi; Suzuki, Ken; Yashiro, Kenta

    2015-01-01

    In the early vertebrate embryo, cardiac progenitor/precursor cells (CPs) give rise to cardiac structures. Better understanding their biological character is critical to understand the heart development and to apply CPs for the clinical arena. However, our knowledge remains incomplete. With the use of single-cell expression profiling, we have now revealed rapid and dynamic changes in gene expression profiles of the embryonic CPs during the early phase after their segregation from the cardiac mesoderm. Progressively, the nascent mesodermal gene Mesp1 terminated, and Nkx2-5+/Tbx5+ population rapidly replaced the Tbx5low+ population as the expression of the cardiac genes Tbx5 and Nkx2-5 increased. At the Early Headfold stage, Tbx5-expressing CPs gradually showed a unique molecular signature with signs of cardiomyocyte differentiation. Lineage-tracing revealed a developmentally distinct characteristic of this population. They underwent progressive differentiation only towards the cardiomyocyte lineage corresponding to the first heart field rather than being maintained as a progenitor pool. More importantly, Tbx5 likely plays an important role in a transcriptional network to regulate the distinct character of the FHF via a positive feedback loop to activate the robust expression of Tbx5 in CPs. These data expands our knowledge on the behavior of CPs during the early phase of cardiac development, subsequently providing a platform for further study.

  5. Proteomics identification of differentially expressed proteins associated with pollen germination and tube growth reveals characteristics of germinated Oryza sativa pollen.

    PubMed

    Dai, Shaojun; Chen, Taotao; Chong, Kang; Xue, Yongbiao; Liu, Siqi; Wang, Tai

    2007-02-01

    Mature pollen from most plant species is metabolically quiescent; however, after pollination, it germinates quickly and gives rise to a pollen tube to transport sperms into the embryo sac. Because methods for collecting a large amount of in vitro germinated pollen grains for transcriptomics and proteomics studies from model plants of Arabidopsis and rice are not available, molecular information about the germination developmental process is lacking. Here we describe a method for obtaining a large quantity of in vitro germinating rice pollen for proteomics study. Two-dimensional electrophoresis of approximately 2300 protein spots revealed 186 that were differentially expressed in mature and germinated pollen. Most showed a changed level of expression, and only 66 appeared to be specific to developmental stages. Furthermore 160 differentially expressed protein spots were identified on mass spectrometry to match 120 diverse protein species. These proteins involve different cellular and metabolic processes with obvious functional skew toward wall metabolism, protein synthesis and degradation, cytoskeleton dynamics, and carbohydrate/energy metabolism. Wall metabolism-related proteins are prominently featured in the differentially expressed proteins and the pollen proteome as compared with rice sporophytic proteomes. Our study also revealed multiple isoforms and differential expression patterns between isoforms of a protein. These results provide novel insights into pollen function specialization.

  6. Transcriptome analysis of neo-tetraploid rice reveals specific differential gene expressions associated with fertility and heterosis.

    PubMed

    Guo, Haibin; Mendrikahy, Jean Nestor; Xie, Lei; Deng, Junfeng; Lu, Zijun; Wu, Jinwen; Li, Xiang; Shahid, Muhammad Qasim; Liu, Xiangdong

    2017-01-10

    Polyploid rice hybrids have a powerful biological and yield potential that may become a new way for rice breeding; however, low fertility is major hindrance in commercial utilization. Here, we developed a neo-tetraploid rice that could overcome the sterility of autotetraploid rice and produce high heterosis. Transcriptome analysis of F1 hybrid developed by crossing neo-tetraploid with autotetraploid rice displayed 807, 663 and 866 differentially expressed genes that uniquely associated with F1 and specific to (DEGFu-sp) anther, ovary and leaf, respectively. Of the DEGFu-sp, 1224 genes displayed nonadditive expression; 44 and 10 genes were annotated as TFs and methyltransferase or hydroxymethyltransferase, respectively. Gene ontology enrichment and co-expression analysis revealed specific differential gene expressions in the DEGFu-sp to leaf, anther and ovary, such as genes related to photosynthesis, metabolic process and transport, and co-expression network including fertility, resistance and epigenetic elements. Of the DEGFu-sp to anther, 42 meiosis stage-specific genes, eight meiosis-related genes, such as RAD51 and SMC2, were identified. We identified 38 miRNAs from DEGFu-sp to anther, and their targets were associated with pollen fertility and retrotransposon protein. Our study provides new germplasm for polyploid rice breeding, and revealed complex regulatory mechanisms that might be associated with heterosis and fertility.

  7. Transcriptome analysis of neo-tetraploid rice reveals specific differential gene expressions associated with fertility and heterosis

    PubMed Central

    Guo, Haibin; Mendrikahy, Jean Nestor; Xie, Lei; Deng, Junfeng; Lu, Zijun; Wu, Jinwen; Li, Xiang; Shahid, Muhammad Qasim; Liu, Xiangdong

    2017-01-01

    Polyploid rice hybrids have a powerful biological and yield potential that may become a new way for rice breeding; however, low fertility is major hindrance in commercial utilization. Here, we developed a neo-tetraploid rice that could overcome the sterility of autotetraploid rice and produce high heterosis. Transcriptome analysis of F1 hybrid developed by crossing neo-tetraploid with autotetraploid rice displayed 807, 663 and 866 differentially expressed genes that uniquely associated with F1 and specific to (DEGFu-sp) anther, ovary and leaf, respectively. Of the DEGFu-sp, 1224 genes displayed nonadditive expression; 44 and 10 genes were annotated as TFs and methyltransferase or hydroxymethyltransferase, respectively. Gene ontology enrichment and co-expression analysis revealed specific differential gene expressions in the DEGFu-sp to leaf, anther and ovary, such as genes related to photosynthesis, metabolic process and transport, and co-expression network including fertility, resistance and epigenetic elements. Of the DEGFu-sp to anther, 42 meiosis stage-specific genes, eight meiosis-related genes, such as RAD51 and SMC2, were identified. We identified 38 miRNAs from DEGFu-sp to anther, and their targets were associated with pollen fertility and retrotransposon protein. Our study provides new germplasm for polyploid rice breeding, and revealed complex regulatory mechanisms that might be associated with heterosis and fertility. PMID:28071676

  8. Gene expression analysis of zebrafish melanocytes, iridophores, and retinal pigmented epithelium reveals indicators of biological function and developmental origin.

    PubMed

    Higdon, Charles W; Mitra, Robi D; Johnson, Stephen L

    2013-01-01

    In order to facilitate understanding of pigment cell biology, we developed a method to concomitantly purify melanocytes, iridophores, and retinal pigmented epithelium from zebrafish, and analyzed their transcriptomes. Comparing expression data from these cell types and whole embryos allowed us to reveal gene expression co-enrichment in melanocytes and retinal pigmented epithelium, as well as in melanocytes and iridophores. We found 214 genes co-enriched in melanocytes and retinal pigmented epithelium, indicating the shared functions of melanin-producing cells. We found 62 genes significantly co-enriched in melanocytes and iridophores, illustrative of their shared developmental origins from the neural crest. This is also the first analysis of the iridophore transcriptome. Gene expression analysis for iridophores revealed extensive enrichment of specific enzymes to coordinate production of their guanine-based reflective pigment. We speculate the coordinated upregulation of specific enzymes from several metabolic pathways recycles the rate-limiting substrate for purine synthesis, phosphoribosyl pyrophosphate, thus constituting a guanine cycle. The purification procedure and expression analysis described here, along with the accompanying transcriptome-wide expression data, provide the first mRNA sequencing data for multiple purified zebrafish pigment cell types, and will be a useful resource for further studies of pigment cell biology.

  9. Single-trial ERP analysis reveals facial expression category in a three-stage scheme.

    PubMed

    Zhang, Dandan; Luo, Wenbo; Luo, Yuejia

    2013-05-28

    Emotional faces are salient stimuli that play a critical role in social interactions. Following up on previous research suggesting that the event-related potentials (ERPs) show differential amplitudes in response to various facial expressions, the current study used trial-to-trial variability assembled from six discriminating ERP components to predict the facial expression categories in individual trials. In an experiment involved 17 participants, fearful trials were differentiated from non-fearful trials as early as the intervals of N1 and P1, with a mean predictive accuracy of 87%. Single-trial features in the occurrence of N170 and vertex positive potential could distinguish between emotional and neutral expressions (accuracy=90%). Finally, the trials associated with fearful, happy, and neutral faces were completely separated during the window of N3 and P3 (accuracy=83%). These categorization findings elucidated the temporal evolution of facial expression extraction, and demonstrated that the spatio-temporal characteristics of single-trial ERPs can distinguish facial expressions according to a three-stage scheme, with "fear popup," "emotional/unemotional discrimination," and "complete separation" as processing stages. This work constitutes the first examination of neural processing dynamics beyond multitrial ERP averaging, and directly relates the prediction performance of single-trial classifiers to the progressive brain functions of emotional face discrimination.

  10. 40 CFR 798.3300 - Oncogenicity.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... clinical abnormalities), gross lesions, identified target organs, body weight changes, effects on mortality... (CONTINUED) HEALTH EFFECTS TESTING GUIDELINES Chronic Exposure § 798.3300 Oncogenicity. (a) Purpose. The... of chronic effects. (ii) The high dose level should elicit signs of minimal toxicity...

  11. 40 CFR 798.3300 - Oncogenicity.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... clinical abnormalities), gross lesions, identified target organs, body weight changes, effects on mortality...) HEALTH EFFECTS TESTING GUIDELINES Chronic Exposure § 798.3300 Oncogenicity. (a) Purpose. The objective of... of chronic effects. (ii) The high dose level should elicit signs of minimal toxicity...

  12. Oncogenic mutations of thyroid hormone receptor β

    PubMed Central

    Park, Jeong Won; Zhao, Li; Willingham, Mark; Cheng, Sheue-yann

    2015-01-01

    The C-terminal frame-shift mutant of the thyroid hormone receptor TRβ1, PV, functions as an oncogene. An important question is whether the oncogenic activity of mutated TRβ1 is uniquely dependent on the PV mutated sequence. Using four C-terminal frame-shift mutants—PV, Mkar, Mdbs, and AM—we examined that region in the oncogenic actions of TRβ1 mutants. Remarkably, these C-terminal mutants induced similar growth of tumors in mouse xenograft models. Molecular analyses showed that they physically interacted with the p85α regulatory subunit of PI3K similarly in cells. In vitro GST-binding assay showed that they bound to the C-terminal Src-homology 2 (CSH2) of p85α with markedly higher avidity. The sustained association of mutants with p85α led to activation of the common PI3K-AKT-ERK/STAT3 signaling to promote cell proliferation and invasion and to inhibit apoptosis. Thus, these results argue against the oncogenic activity of PV being uniquely dependent on the PV mutated sequence. Rather, these four mutants could favor a C-terminal conformation that interacted with the CSH2 domain of p85α to initiate activation of PI3K to relay downstream signaling to promote tumorigenesis. Thus, we propose that the mutated C-terminal region of TRβ1 could function as an “onco-domain” and TRβ1 is a potential therapeutic target. PMID:25924236

  13. Novel Oncogenes in Breast Cancer Development

    DTIC Science & Technology

    2002-07-01

    determinants that contribute to the development of breast cancer remain unknown We have developed and applied a novel retrovirus-based library ... screening strategy coupled to a biological assay for growth transformation, to identify novel oncogenes in breast cancer development The approach involves the

  14. Global gene expression profiles reveal significant nuclear reprogramming by the blastocyst stage after cloning.

    PubMed

    Smith, Sadie L; Everts, Robin E; Tian, X Cindy; Du, Fuliang; Sung, Li-Ying; Rodriguez-Zas, Sandra L; Jeong, Byeong-Seon; Renard, Jean-Paul; Lewin, Harris A; Yang, Xiangzhong

    2005-12-06

    Nuclear transfer (NT) has potential applications in agriculture and biomedicine, but the technology is hindered by low efficiency. Global gene expression analysis of clones is important for the comprehensive study of nuclear reprogramming. Here, we compared global gene expression profiles of individual bovine NT blastocysts with their somatic donor cells and fertilized control embryos using cDNA microarray technology. The NT embryos' gene expression profiles were drastically different from those of their donor cells and closely resembled those of the naturally fertilized embryos. Our findings demonstrate that the NT embryos have undergone significant nuclear reprogramming by the blastocyst stage; however, problems may occur during redifferentiation for tissue genesis and organogenesis, and small reprogramming errors may be magnified downstream in development.

  15. Viral oncogenes, proto-oncogenes and homoeotic genes related to cell proliferation and differentiation.

    PubMed

    Antohi, S; Antohi-Talle, O

    1987-01-01

    Molecular studies on viral oncogenes and their products have led to the discovery of physiological proto-oncogenes, involved in the control of cell proliferation and gene activation. Other genetic and molecular investigations, initiated in Drosophila melanogaster and continued in different multicellular eukaryotes, have made evident the homoeotic genes, which are directly correlated with cell specialization, in the complex processes of differentiation and morphogenesis. Both gene classes are conserved to a high extent during evolution. They are involved in the eukaryotic mechanisms of differentiation control and proto-oncogenes, in particular, are related to malignant transformation. Some available data suggest a certain extent of relatedness between the gene products of both gene classes. A differentiation trigger model, including retroviral transposition, homoeotic genes and proto-oncogenes is discussed.

  16. Transcriptomic Analysis of Thermally Stressed Symbiodinium Reveals Differential Expression of Stress and Metabolism Genes.

    PubMed

    Gierz, Sarah L; Forêt, Sylvain; Leggat, William

    2017-01-01

    Endosymbioses between dinoflagellate algae (Symbiodinium sp.) and scleractinian coral species form the foundation of coral reef ecosystems. The coral symbiosis is highly susceptible to elevated temperatures, resulting in coral bleaching, where the algal symbiont is released from host cells. This experiment aimed to determine the transcriptional changes in cultured Symbiodinium, to better understand the response of cellular mechanisms under future temperature conditions. Cultures were exposed to elevated temperatures (average 31°C) or control conditions (24.5°C) for a period of 28 days. Whole transcriptome sequencing of Symbiodinium cells on days 4, 19, and 28 were used to identify differentially expressed genes under thermal stress. A large number of genes representing 37.01% of the transcriptome (∼23,654 unique genes, FDR < 0.05) with differential expression were detected at no less than one of the time points. Consistent with previous studies of Symbiodinium gene expression, fold changes across the transcriptome were low, with 92.49% differentially expressed genes at ≤2-fold change. The transcriptional response included differential expression of genes encoding stress response components such as the antioxidant network and molecular chaperones, cellular components such as core photosynthesis machinery, integral light-harvesting protein complexes and enzymes such as fatty acid desaturases. Differential expression of genes encoding glyoxylate cycle enzymes were also found, representing the first report of this in Symbiodinium. As photosynthate transfer from Symbiodinium to coral hosts provides up to 90% of a coral's daily energy requirements, the implications of altered metabolic processes from exposure to thermal stress found in this study on coral-Symbiodinium associations are unknown and should be considered when assessing the stability of the symbiotic relationship under future climate conditions.

  17. Gene and microRNA expression reveals sensitivity to paclitaxel in laryngeal cancer cell line

    PubMed Central

    Xu, Cheng-Zhi; Xie, Jin; Jin, Bin; Chen, Xin-Wei; Sun, Zhen-Feng; Wang, Bao-Xing; Dong, Pin

    2013-01-01

    Paclitaxel is a widely used chemotherapy drug for advanced laryngeal cancer patients. However, the fact that there are 20-40% of advanced laryngeal cancer patients do not response to paclitaxel makes it necessary to figure out potential biomarkers for paclitaxel sensitivity prediction. In this work, Hep2, a laryngeal cancer cell line, untreated or treated with lower dose of paclitaxel for 24 h, was applied to DNA microarray chips for gene and miR expression profile analysis. Expression of eight genes altered significantly following paclitaxel treatment, which was further validated by quantitative real-time PCR. Four up-regulated genes were ID2, BMP4, CCL4 and ACTG2, in which ID2 and BMP4 were implicated to be involved in several drugs sensitivity. While the down-regulated four genes, MAPK4, FASN, INSIG1 and SCD, were mainly linked to the endoplasmic reticulum and fatty acid biosynthesis, these two cell processes that are associated with drug sensitivity by increasing evidences. After paclitaxel treatment, expression of 49 miRs was significantly altered. Within these miRs, the most markedly expression-changed were miR-31-star, miR-1264, miR-3150b-5p and miR-210. While the miRs putatively modulated the mRNA expression of the most significantly expression-altered genes were miR-1264, miR-130a, miR-27b, miR-195, miR-1291, miR-214, miR-1277 and miR-1265, which were obtained by miR target prediction and miRNA target correlation. Collectively, our study might provide potential biomarkers for paclitaxel sensitivity prediction and drug resistance targets in laryngeal cancer patients. PMID:23826416

  18. Ultra-Deep Sequencing Reveals the microRNA Expression Pattern of the Human Stomach

    PubMed Central

    Ribeiro-dos-Santos, Ândrea; Khayat, André S.; Silva, Artur; Alencar, Dayse O.; Lobato, Jessé; Luz, Larissa; Pinheiro, Daniel G.; Varuzza, Leonardo; Assumpção, Monica; Assumpção, Paulo; Santos, Sidney; Zanette, Dalila L.; Silva, Wilson A.; Burbano, Rommel; Darnet, Sylvain

    2010-01-01

    Background While microRNAs (miRNAs) play important roles in tissue differentiation and in maintaining basal physiology, little is known about the miRNA expression levels in stomach tissue. Alterations in the miRNA profile can lead to cell deregulation, which can induce neoplasia. Methodology/Principal Findings A small RNA library of stomach tissue was sequenced using high-throughput SOLiD sequencing technology. We obtained 261,274 quality reads with perfect matches to the human miRnome, and 42% of known miRNAs were identified. Digital Gene Expression profiling (DGE) was performed based on read abundance and showed that fifteen miRNAs were highly expressed in gastric tissue. Subsequently, the expression of these miRNAs was validated in 10 healthy individuals by RT-PCR showed a significant correlation of 83.97% (P<0.05). Six miRNAs showed a low variable pattern of expression (miR-29b, miR-29c, miR-19b, miR-31, miR-148a, miR-451) and could be considered part of the expression pattern of the healthy gastric tissue. Conclusions/Significance This study aimed to validate normal miRNA profiles of human gastric tissue to establish a reference profile for healthy individuals. Determining the regulatory processes acting in the stomach will be important in the fight against gastric cancer, which is the second-leading cause of cancer mortality worldwide. PMID:20949028

  19. Transcriptomic Analysis of Thermally Stressed Symbiodinium Reveals Differential Expression of Stress and Metabolism Genes

    PubMed Central

    Gierz, Sarah L.; Forêt, Sylvain; Leggat, William

    2017-01-01

    Endosymbioses between dinoflagellate algae (Symbiodinium sp.) and scleractinian coral species form the foundation of coral reef ecosystems. The coral symbiosis is highly susceptible to elevated temperatures, resulting in coral bleaching, where the algal symbiont is released from host cells. This experiment aimed to determine the transcriptional changes in cultured Symbiodinium, to better understand the response of cellular mechanisms under future temperature conditions. Cultures were exposed to elevated temperatures (average 31°C) or control conditions (24.5°C) for a period of 28 days. Whole transcriptome sequencing of Symbiodinium cells on days 4, 19, and 28 were used to identify differentially expressed genes under thermal stress. A large number of genes representing 37.01% of the transcriptome (∼23,654 unique genes, FDR < 0.05) with differential expression were detected at no less than one of the time points. Consistent with previous studies of Symbiodinium gene expression, fold changes across the transcriptome were low, with 92.49% differentially expressed genes at ≤2-fold change. The transcriptional response included differential expression of genes encoding stress response components such as the antioxidant network and molecular chaperones, cellular components such as core photosynthesis machinery, integral light-harvesting protein complexes and enzymes such as fatty acid desaturases. Differential expression of genes encoding glyoxylate cycle enzymes were also found, representing the first report of this in Symbiodinium. As photosynthate transfer from Symbiodinium to coral hosts provides up to 90% of a coral’s daily energy requirements, the implications of altered metabolic processes from exposure to thermal stress found in this study on coral-Symbiodinium associations are unknown and should be considered when assessing the stability of the symbiotic relationship under future climate conditions. PMID:28293249

  20. Characterization of gonadal transcriptomes from Nile tilapia (Oreochromis niloticus) reveals differentially expressed genes.

    PubMed

    Tao, Wenjing; Yuan, Jing; Zhou, Linyan; Sun, Lina; Sun, Yunlv; Yang, Shijie; Li, Minghui; Zeng, Sheng; Huang, Baofeng; Wang, Deshou

    2013-01-01

    Four pairs of XX and XY gonads from Nile tilapia were sequenced at four developmental stages, 5, 30, 90, and 180 days after hatching (dah) using Illumina Hiseq(TM) technology. This produced 28 Gb sequences, which were mapped to 21,334 genes. Of these, 259 genes were found to be specifically expressed in XY gonads, and 69 were found to be specific to XX gonads. Totally, 187 XX- and 1,358 XY-enhanced genes were identified, and 2,978 genes were found to be co-expressed in XX and XY gonads. Almost all steroidogenic enzymes, including cyp19a1a, were up-regulated in XX gonads at 5 dah; but in XY gonads these enzymes, including cyp11b2, were significantly up-regulated at 90 dah, indicating that, at a time critical to sex determination, the XX fish produced estrogen and the XY fish did not produce androgens. The most pronounced expression of steroidogenic enzyme genes was observed at 30 and 90 dah for XX and XY gonads, corresponding to the initiation of germ cell meiosis in the female and male gonads, respectively. Both estrogen and androgen receptors were found to be expressed in XX gonads, but only estrogen receptors were expressed in XY gonads at 5 dah. This could explain why exogenous steroid treatment induced XX and XY sex reversal. The XX-enhanced expression of cyp19a1a and cyp19a1b at all stages suggests an important role for estrogen in female sex determination and maintenance of phenotypic sex. This work is the largest collection of gonadal transcriptome data in tilapia and lays the foundation for future studies into the molecular mechanisms of sex determination and maintenance of phenotypic sex in non-model teleosts.

  1. Role of papillomavirus oncogenes in human cervical cancer: Transgenic animal studies

    SciTech Connect

    Griep, A.E.; Lambert, P.F.

    1994-05-01

    Human papillomaviruses are believed to be etiologic agents for the majority of human cervical carcinoma, a common cancer that is a leading cause of death by cancer among women worldwide. In cervical carcinoma, a subset of papillomaviral genes, namely E6 and E7, are expressed. In vitro tissue culture studies indicate that HPV E6 and E7 are oncogenes, and that their oncogenicity is due in part to their capacity to inactivate cellular tumor suppressor genes. The behavior of E6 and E7 in vitro and the genetic evidence from analysis of human cancers suggest that the E6 and E7 genes play a significant role in the development of cervical cancer. This hypothesis is now being tested using animal models. In this review, we summarize our current knowledge of the oncogenicity of papillomavirus genes that has been generated through their study in transgenic mice. 82 refs., 4 figs., 1 tab.

  2. Pten Inactivation Accelerates Oncogenic K-ras-Initiated Tumorigenesis in a Mouse Model of Lung Cancer

    PubMed Central

    Iwanaga, Kentaro; Yang, Yanan; Raso, Maria Gabriela; Ma, Lijiang; Hanna, Amy E.; Thilaganathan, Nishan; Moghaddam, Seyed; Evans, Christopher M.; Li, Huaiguang; Cai, Wei-Wen; Sato, Mitsuo; Minna, John D.; Wu, Hong; Creighton, Chad J.; Demayo, Francesco J.; Wistuba, Ignacio I.; Kurie, Jonathan M.

    2009-01-01

    Phosphatase and tensin homologue deleted from chromosome 10 (Pten) is expressed aberrantly in non-small cell lung cancer cells, but the role of Pten in lung neoplasia has not been fully elucidated. In this study, we used a genetic approach to inactivate Pten in the bronchial epithelium of mice. Although, by itself, Pten inactivation had no discernible effect on bronchial epithelial histology, it accelerated lung tumorigenesis initiated by oncogenic K-ras, causing more rapid lethality than that induced by oncogenic K-ras alone (8 weeks versus 24 weeks of median duration of survival, respectively). Lung tumors arose in K-ras mutant, Pten-deficient mice that rapidly obstructed bronchial lumina and replaced alveolar spaces. Relative to K-ras mutant tumors, the K-ras mutant, Pten-deficient tumors exhibited more advanced histologic severity and more prominent inflammation and vascularity. Thus, Pten inactivation cooperated with oncogenic K-ras in promoting lung tumorigenesis. PMID:18281487

  3. Pancreatitis-induced Inflammation Contributes to Pancreatic Cancer by Inhibiting Oncogene-Induced Senescence

    PubMed Central

    Guerra, Carmen; Collado, Manuel; Navas, Carolina; Schuhmacher, Alberto J; Hernández-Porras, Isabel; Cañamero, Marta; Rodriguez-Justo, Manuel; Serrano, Manuel; Barbacid, Mariano

    2016-01-01

    Pancreatic acinar cells of adult mice (≥P60) are resistant to transformation by some of the most robust oncogenic insults including expression of K-Ras oncogenes and loss of p16Ink4a/p19Arf or Trp53 tumor suppressors. Yet, these acinar cells yield pancreatic intraepithelial neoplasias (mPanIN) and ductal adenocarcinomas (mPDAC) if exposed to limited bouts of non-acute pancreatitis, providing they harbor K-Ras oncogenes. Pancreatitis contributes to tumor progression by abrogating the senescence barrier characteristic of low-grade mPanINs. Attenuation of pancreatitis-induced inflammation also accelerates tissue repair and thwarts mPanIN expansion. Patients with chronic pancreatitis display senescent PanINs, if they have received anti-inflammatory drugs. These results put forward the concept that anti-inflammatory treatment of people diagnosed with pancreatitis may reduce their risk of developing PDAC. PMID:21665147

  4. Monoclonal antibodies to murine thrombospondin-1 and thrombospondin-2 reveal differential expression patterns in cancer and low antigen expression in normal tissues

    SciTech Connect

    Bujak, Emil; Pretto, Francesca; Ritz, Danilo; Gualandi, Laura; Wulhfard, Sarah; Neri, Dario

    2014-09-10

    There is a considerable interest for the discovery and characterization of tumor-associated antigens, which may facilitate antibody-based pharmacodelivery strategies. Thrombospondin-1 and thrombospondin-2 are homologous secreted proteins, which have previously been reported to be overexpressed during remodeling typical for wound healing and tumor progression and to possibly play a functional role in cell proliferation, migration and apoptosis. To our knowledge, a complete immunohistochemical characterization of thrombospondins levels in normal rodent tissues has not been reported so far. Using antibody phage technology, we have generated and characterized monoclonal antibodies specific to murine thrombospondin-1 and thrombospondin-2, two antigens which share 62% aminoacid identity. An immunofluorescence analysis revealed that both antigens are virtually undetectable in normal mouse tissues, except for a weak staining of heart tissue by antibodies specific to thrombospondin-1. The analysis also showed that thrombospondin-1 was strongly expressed in 5/7 human tumors xenografted in nude mice, while it was only barely detectable in 3/8 murine tumors grafted in immunocompetent mice. By contrast, a high-affinity antibody to thrombospondin-2 revealed a much lower level of expression of this antigen in cancer specimens. Our analysis resolves ambiguities related to conflicting reports on thrombosponding expression in health and disease. Based on our findings, thrombospondin-1 (and not thrombospondin-2) may be considered as a target for antibody-based pharmacodelivery strategies, in consideration of its low expression in normal tissues and its upregulation in cancer. - Highlights: • High affinity monoclonal antibodies to murine and human TSP1 and 2 were raised. • Both antigens are virtually undetectable in normal mouse tissues. • Strong positivity of human tumor xenografts for TSP1 was detected. • Study revealed much lower level of TSP2 expression in cancer specimens

  5. Analysis of NUAK1 and NUAK2 expression during early chick development reveals specific patterns in the developing head.

    PubMed

    Bekri, Abdelhamid; Billaud, Marc; Thélu, Jacques

    2014-01-01

    Several human diseases are associated with the NUAK1 and NUAK2 genes. These genes encode kinases, members of the AMPK-related kinases (ARK) gene family. Both NUAK1 and NUAK2 are known targets of the serine threonine kinase LKB1, a tumor suppressor involved in regulating cell polarity. While much is known about their functions in disease, their expression pattern in normal development has not been extensively studied. Here, we present the expression patterns for NUAK1 and NUAK2 in the chick during early-stage embryogenesis, until day 3 (Hamburger and Hamilton stage HH20). Several embryonic structures, in particular the nascent head, showed distinct expression levels. NUAK1 expression was first detected at stage HH6 in the rostral neural folds. It was then expressed (HH7-11) throughout the encephalalon, predominantly in the telencephalon and mesencephalon. NUAK1 expression was also detected in the splanchnic endoderm area at HH8-10, and in the vitellin vein derived from this area, but not in the heart. NUAK2 expression was first detected at stage HH6 in the neural folds. It was then found throughout the encephalon at stage HH20. Particular attention was paid in this study to the dorsal ectoderm at stages HH7 and HH8, where a local deficit or accumulation of NUAK2 mRNA were found to correlate with the direction of curvature of the neural plate. This is the first description of NUAK1 and NUAK2 expression patterns in the chick during early development; it reveals non-identical expression profiles for both genes in neural development.

  6. Novel middle-type Kenyon cells in the honeybee brain revealed by area-preferential gene expression analysis.

    PubMed

    Kaneko, Kumi; Ikeda, Tsubomi; Nagai, Mirai; Hori, Sayaka; Umatani, Chie; Tadano, Hiroto; Ugajin, Atsushi; Nakaoka, Takayoshi; Paul, Rajib Kumar; Fujiyuki, Tomoko; Shirai, Kenichi; Kunieda, Takekazu; Takeuchi, Hideaki; Kubo, Takeo

    2013-01-01

    The mushroom bodies (a higher center) of the honeybee (Apis mellifera L) brain were considered to comprise three types of intrinsic neurons, including large- and small-type Kenyon cells that have distinct gene expression profiles. Although previous neural activity mapping using the immediate early gene kakusei suggested that small-type Kenyon cells are mainly active in forager brains, the precise Kenyon cell types that are active in the forager brain remain to be elucidated. We searched for novel gene(s) that are expressed in an area-preferential manner in the honeybee brain. By identifying and analyzing expression of a gene that we termed mKast (middle-type Kenyon cell-preferential arrestin-related protein), we discovered novel 'middle-type Kenyon cells' that are sandwiched between large- and small-type Kenyon cells and have a gene expression profile almost complementary to those of large- and small-type Kenyon cells. Expression analysis of kakusei revealed that both small-type Kenyon cells and some middle-type Kenyon cells are active in the forager brains, suggesting their possible involvement in information processing during the foraging flight. mKast expression began after the differentiation of small- and large-type Kenyon cells during metamorphosis, suggesting that middle-type Kenyon cells differentiate by modifying some characteristics of large- and/or small-type Kenyon cells. Interestingly, CaMKII and mKast, marker genes for large- and middle-type Kenyon cells, respectively, were preferentially expressed in a distinct set of optic lobe (a visual center) neurons. Our findings suggested that it is not simply the Kenyon cell-preferential gene expression profiles, rather, a 'clustering' of neurons with similar gene expression profiles as particular Kenyon cell types that characterize the honeybee mushroom body structure.

  7. Novel Middle-Type Kenyon Cells in the Honeybee Brain Revealed by Area-Preferential Gene Expression Analysis

    PubMed Central

    Kaneko, Kumi; Umatani, Chie; Tadano, Hiroto; Ugajin, Atsushi; Nakaoka, Takayoshi; Paul, Rajib Kumar; Fujiyuki, Tomoko; Shirai, Kenichi; Kunieda, Takekazu; Takeuchi, Hideaki; Kubo, Takeo

    2013-01-01

    The mushroom bodies (a higher center) of the honeybee (Apis mellifera L) brain were considered to comprise three types of intrinsic neurons, including large- and small-type Kenyon cells that have distinct gene expression profiles. Although previous neural activity mapping using the immediate early gene kakusei suggested that small-type Kenyon cells are mainly active in forager brains, the precise Kenyon cell types that are active in the forager brain remain to be elucidated. We searched for novel gene(s) that are expressed in an area-preferential manner in the honeybee brain. By identifying and analyzing expression of a gene that we termed mKast (middle-type Kenyon cell-preferential arrestin-related protein), we discovered novel ‘middle-type Kenyon cells’ that are sandwiched between large- and small-type Kenyon cells and have a gene expression profile almost complementary to those of large– and small-type Kenyon cells. Expression analysis of kakusei revealed that both small-type Kenyon cells and some middle-type Kenyon cells are active in the forager brains, suggesting their possible involvement in information processing during the foraging flight. mKast expression began after the differentiation of small- and large-type Kenyon cells during metamorphosis, suggesting that middle-type Kenyon cells differentiate by modifying some characteristics of large– and/or small-type Kenyon cells. Interestingly, CaMKII and mKast, marker genes for large– and middle-type Kenyon cells, respectively, were preferentially expressed in a distinct set of optic lobe (a visual center) neurons. Our findings suggested that it is not simply the Kenyon cell-preferential gene expression profiles, rather, a ‘clustering’ of neurons with similar gene expression profiles as particular Kenyon cell types that characterize the honeybee mushroom body structure. PMID:23990981

  8. Expression of progerin in aging mouse brains reveals structural nuclear abnormalities without detectible significant alterations in gene expression, hippocampal stem cells or behavior.

    PubMed

    Baek, Jean-Ha; Schmidt, Eva; Viceconte, Nikenza; Strandgren, Charlotte; Pernold, Karin; Richard, Thibaud J C; Van Leeuwen, Fred W; Dantuma, Nico P; Damberg, Peter; Hultenby, Kjell; Ulfhake, Brun; Mugnaini, Enrico; Rozell, Björn; Eriksson, Maria

    2015-03-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a segmental progeroid syndrome with multiple features suggestive of premature accelerated aging. Accumulation of progerin is thought to underlie the pathophysiology of HGPS. However, despite ubiquitous expression of lamin A in all differentiated cells, the HGPS mutation results in organ-specific defects. For example, bone and skin are strongly affected by HGPS, while the brain appears to be unaffected. There are no definite explanations as to the variable sensitivity to progeria disease among different organs. In addition, low levels of progerin have also been found in severa