Molecular analysis of aniridia patients for deletions involving the Wilms' tumor gene

NARCIS (Netherlands)

Drechsler, M.; Meijers-Heijboer, E. J.; Schneider, S.; Schurich, B.; Grond-Ginsbach, C.; Tariverdian, G.; Kantner, G.; Blankenagel, A.; Kaps, D.; Schroeder-Kurth, T.

1994-01-01

A human aniridia candidate (AN) gene on chromosome 11p13 has been cloned and characterized. The AN gene is the second cloned gene of the contiguous genes syndrome WAGR (Wilms' tumor, aniridia, genitourinary malformations, mental retardation) on chromosome 11p13, WT1 being the first gene cloned.

Structures of native and affinity-enhanced WT1 epitopes bound to HLA-A*0201: Implications for WT1-based cancer therapeutics

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Borbulevych, Oleg Y.; Do, Priscilla; Baker, Brian M. (Notre)

2010-09-07

Presentation of peptides by class I or class II major histocompatibility complex (MHC) molecules is required for the initiation and propagation of a T cell-mediated immune response. Peptides from the Wilms Tumor 1 transcription factor (WT1), upregulated in many hematopoetic and solid tumors, can be recognized by T cells and numerous efforts are underway to engineer WT1-based cancer vaccines. Here we determined the structures of the class I MHC molecule HLA-A*0201 bound to the native 126-134 epitope of the WT1 peptide and a recently described variant (R1Y) with improved MHC binding. The R1Y variant, a potential vaccine candidate, alters the positions of MHC charged side chains near the peptide N-terminus and significantly reduces the peptide/MHC electrostatic surface potential. These alterations indicate that the R1Y variant is an imperfect mimic of the native WT1 peptide, and suggest caution in its use as a therapeutic vaccine. Stability measurements revealed how the R1Y substitution enhances MHC binding affinity, and together with the structures suggest a strategy for engineering WT1 variants with improved MHC binding that retain the structural features of the native peptide/MHC complex.

Development of oral cancer vaccine using recombinant Bifidobacterium displaying Wilms' tumor 1 protein.

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Kitagawa, Koichi; Oda, Tsugumi; Saito, Hiroki; Araki, Ayame; Gonoi, Reina; Shigemura, Katsumi; Hashii, Yoshiko; Katayama, Takane; Fujisawa, Masato; Shirakawa, Toshiro

2017-06-01

Several types of vaccine-delivering tumor-associated antigens (TAAs) have been developed in basic and clinical research. Wilms' tumor 1 (WT1), identified as a gene responsible for pediatric renal neoplasm, is one of the most promising TAA for cancer immunotherapy. Peptide and dendritic cell-based WT1 cancer vaccines showed some therapeutic efficacy in clinical and pre-clinical studies but as yet no oral WT1 vaccine can be administrated in a simple and easy way. In the present study, we constructed a novel oral cancer vaccine using a recombinant Bifidobacterium longum displaying WT1 protein. B. longum 420 was orally administered into mice inoculated with WT1-expressing tumor cells for 4 weeks to examine anti-tumor effects. To analyze the WT1-specific cellular immune responses to oral B. longum 420, mice splenocytes were isolated and cytokine production and cytotoxic activities were determined. Oral administrations of B. longum 420 significantly inhibited WT1-expressing tumor growth and prolonged survival in mice. Immunohistochemical study and immunological assays revealed that B. longum 420 substantially induced tumor infiltration of CD4 + T and CD8 + T cells, systemic WT1-specific cytokine production, and cytotoxic activity mediated by WT1-epitope specific cytotoxic T lymphocytes, with no apparent adverse effects. Our novel oral cancer vaccine safely induced WT1-specific cellular immunity via activation of the gut mucosal immune system and achieved therapeutic efficacy with several practical advantages over existing non-oral vaccines.

Overexpression of Wilms Tumor 1 Gene as a Negative Prognostic Indicator in Acute Myeloid Leukemia

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Mi, Ruihua; Ding, Jing; Wang, Xianwei; Hu, Jieying; Fan, Ruihua; Wei, Xudong; Song, Yongping; Zhao, Richard Y.

2014-01-01

Chromosomal aberrations are useful in assessing treatment options and clinical outcomes of acute myeloid leukemia (AML) patients. However, 40∼50% of the AML patients showed no chromosomal abnormalities, i.e., with normal cytogenetics aka the CN-AML patients. Testing of molecular aberrations such as FLT3 or NPM1 can help to define clinical outcomes in the CN-AML patients but with various successes. Goal of this study was to test the possibility of Wilms’ tumor 1 (WT1) gene overexpression as an additional molecular biomarker. A total of 103 CN-AML patients, among which 28% had overexpressed WT1, were studied over a period of 38 months. Patient’s response to induction chemotherapy as measured by the complete remission (CR) rate, disease-free survival (DFS) and overall survival (OS) were measured. Our data suggested that WT1 overexpression correlated negatively with the CR rate, DFS and OS. Consistent with previous reports, CN-AML patients can be divided into three different risk subgroups based on the status of known molecular abnormalities, i.e., the favorable (NPM1mt/no FLT3ITD), the unfavorable (FLT3ITD) and the intermediate risk subgroups. The WT1 overexpression significantly reduced the CR, DFS and OS in both the favorable and unfavorable groups. As the results, patients with normal WT1 gene expression in the favorable risk group showed the best clinical outcomes and all survived with complete remission and disease-free survival over the 37 month study period; in contrast, patients with WT1 overexpression in the unfavorable risk group displayed the worst clinical outcomes. WT1 overexpression by itself is an independent and negative indicator for predicting CR rate, DFS and OS of the CN-AML patients; moreover, it increases the statistical power of predicting the same clinical outcomes when it is combined with the NPM1 mt or the FLT3 ITD genotypes that are the good or poor prognostic markers of CN-AML. PMID:24667279

Regulation of radiation-induced apoptosis by early growth response-1 gene in solid tumors

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Ahmed, M.

2003-01-01

Ionizing radiation exposure is associated with activation of certain immediate-early genes that function as transcription factors. These include members of jun or fos and early growth response (EGR) gene families. In particular, the functional role of EGR-1 in radiation-induced signaling is pivotal since the promoter of EGR-1 contains radiation-inducible CArG DNA sequences. The Egr-1 gene belongs to a family of Egr genes that includes EGR-2, EGR-3, EGR-4, EGR-α and the tumor suppressor, Wilms' tumor gene product, WT1. The Egr-1 gene product, EGR-1, is a nuclear protein that contains three zinc fingers of the C 2 H 2 subtype. The EGR-1 GC-rich consensus target sequence, 5'-GCGT/GGGGCG-3' or 5'-TCCT/ACCTCCTCC-3', has been identified in the promoter regions of transcription factors, growth factors, receptors, cell cycle regulators and pro-apoptotic genes. The gene targets mediated by Egr-1 in response to ionizing radiation include TNF-α , p53, Rb and Bax, all these are effectors of apoptosis. Based on these targets, Egr-1 is a pivotal gene that initiates early signal transduction events in response to ionizing radiation leading to either growth arrest or cell death in tumor cells. There are two potential application of Egr-1 gene in therapy of cancer. First, the Egr-1 promoter contains information for appropriate spatial and temporal expression in-vivo that can be regulated by ionizing radiation to control transcription of genes that have pro-apoptotic and suicidal function. Secondly, EGR-1 protein can eliminate 'induced-radiation resistance' by inhibiting the functions of radiation-induced pro-survival genes (NFκB activity and bcl-2 expression) and activate pro-apoptotic genes (such as bax) to confer a significant radio-sensitizing effect. Together, the reported findings from my laboratory demonstrate clearly that EGR-1 is an early central gene that confers radiation sensitivity and its pro-apoptotic functions are synergized by abrogation of induced radiation

Physical interaction between Wilms tumor 1 and p73 proteins modulates their functions

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Scharnhorst, V.; Dekker, P.; Eb, van der A.J.; Jochemsen, A.G.

2014-01-01

The WT1 gene, which is heterozygously mutated or deleted in congenital anomaly syndromes and homozygously mutated in about 15% of all Wilms tumors, encodes tissue-specific developmental regulators. Through alternative mRNA splicing, four main WT1 protein isoforms are synthesized. All isoforms can

Regulation of HtrA2 on WT1 gene expression under imatinib stimulation and its effects on the cell biology of K562 cells.

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Zhang, Lixia; Li, Yan; Li, Xiaoyan; Zhang, Qing; Qiu, Shaowei; Zhang, Qi; Wang, Min; Xing, Haiyan; Rao, Qing; Tian, Zheng; Tang, Kejing; Wang, Jianxiang; Mi, Yingchang

2017-09-01

The aim of the present study was to investigate the regulation of Wilms Tumor 1 (WT1) by serine protease high-temperature requirement protein A2 (HtrA2), a member of the Htr family, in K562 cells. In addition, the study aimed to observe the effect of this regulation on cell biological functions and its associated mechanisms. Expression of WT1 and HtrA2 mRNA, and proteins following imatinib and the HtrA2 inhibitor 5-[5-(2-nitrophenyl) furfuryl iodine]-1, 3-diphenyl-2-thiobarbituric acid (UCF-101) treatment was detected with reverse transcription-quantitative polymerase chain reaction and western blot analysis. Subsequent to treatment with drugs and UCF-101, the proliferative function of K562 cells was detected using MTT assays, and the rate of apoptosis was detected using Annexin V with propidium iodide flow cytometry in K562 cells. The protein levels in the signaling pathway were analyzed using western blotting following treatment with imatinib and UCF-101. In K562 cells, imatinib treatment activated HtrA2 gene at a transcription level, while the WT1 gene was simultaneously downregulated. Following HtrA2 inhibitor (UCF-101) treatment, the downregulation of WT1 increased gradually. At the protein level, imatinib induced the increase in HtrA2 protein level and concomitantly downregulated WT1 protein level. Subsequent to HtrA2 inhibition by UCF-101, the WT1 protein level decreased temporarily, but eventually increased. Imatinib induced apoptosis in K562 cells, but this effect was attenuated by the HtrA2 inhibitor UCF-101, resulting in the upregulation of the WT1 protein level. However; UCF-101 did not markedly change the proliferation inhibition caused by imatinib. Imatinib activated the p38 mitogen activated protein kinase (p38 MAPK) signaling pathway in K562 cells, and UCF-101 affected the activation of imatinib in the p38 MAPK signaling pathway. Imatinib inhibited the extracellular signal-related kinase (ERK1/2) pathway markedly and persistently, but UCF-101

Gene expression profiles in primary pancreatic tumors and metastatic lesions of Ela-c-myc transgenic mice

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Liao Dezhong J

2008-01-01

Full Text Available Abstract Background Pancreatic carcinoma usually is a fatal disease with no cure, mainly due to its invasion and metastasis prior to diagnosis. We analyzed the gene expression profiles of paired primary pancreatic tumors and metastatic lesions from Ela-c-myc transgenic mice in order to identify genes that may be involved in the pancreatic cancer progression. Differentially expressed selected genes were verified by semi-quantitative and quantitative RT-PCR. To further evaluate the relevance of some of the selected differentially expressed genes, we investigated their expression pattern in human pancreatic cancer cell lines with high and low metastatic potentials. Results Data indicate that genes involved in posttranscriptional regulation were a major functional category of upregulated genes in both primary pancreatic tumors (PT and liver metastatic lesions (LM compared to normal pancreas (NP. In particular, differential expression for splicing factors, RNA binding/pre-mRNA processing factors and spliceosome related genes were observed, indicating that RNA processing and editing related events may play critical roles in pancreatic tumor development and progression. High expression of insulin growth factor binding protein-1 (Igfbp1 and Serine proteinase inhibitor A1 (Serpina1, and low levels or absence of Wt1 gene expression were exclusive to liver metastatic lesion samples. Conclusion We identified Igfbp1, Serpina1 and Wt1 genes that are likely to be clinically useful biomarkers for prognostic or therapeutic purposes in metastatic pancreatic cancer, particularly in pancreatic cancer where c-Myc is overexpressed.

Gene expression profiles in primary pancreatic tumors and metastatic lesions of Ela-c-myc transgenic mice.

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Thakur, Archana; Bollig, Aliccia; Wu, Jiusheng; Liao, Dezhong J

2008-01-24

Pancreatic carcinoma usually is a fatal disease with no cure, mainly due to its invasion and metastasis prior to diagnosis. We analyzed the gene expression profiles of paired primary pancreatic tumors and metastatic lesions from Ela-c-myc transgenic mice in order to identify genes that may be involved in the pancreatic cancer progression. Differentially expressed selected genes were verified by semi-quantitative and quantitative RT-PCR. To further evaluate the relevance of some of the selected differentially expressed genes, we investigated their expression pattern in human pancreatic cancer cell lines with high and low metastatic potentials. Data indicate that genes involved in posttranscriptional regulation were a major functional category of upregulated genes in both primary pancreatic tumors (PT) and liver metastatic lesions (LM) compared to normal pancreas (NP). In particular, differential expression for splicing factors, RNA binding/pre-mRNA processing factors and spliceosome related genes were observed, indicating that RNA processing and editing related events may play critical roles in pancreatic tumor development and progression. High expression of insulin growth factor binding protein-1 (Igfbp1) and Serine proteinase inhibitor A1 (Serpina1), and low levels or absence of Wt1 gene expression were exclusive to liver metastatic lesion samples. We identified Igfbp1, Serpina1 and Wt1 genes that are likely to be clinically useful biomarkers for prognostic or therapeutic purposes in metastatic pancreatic cancer, particularly in pancreatic cancer where c-Myc is overexpressed.

Monitoring therapy with MEK inhibitor U0126 in a novel Wilms tumor model in Wt1 knockout Igf2 transgenic mice using 18F-FDG PET with dual-contrast enhanced CT and MRI: early metabolic response without inhibition of tumor growth.

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Flores, Leo G; Yeh, Hsin-Hsien; Soghomonyan, Suren; Young, Daniel; Bankson, James; Hu, Qianghua; Alauddin, Mian; Huff, Vicki; Gelovani, Juri G

2013-04-01

The understanding of the role of genetic alterations in Wilms tumor development could be greatly advanced using a genetically engineered mouse models that can replicate the development and progression of this disease in human patients and can be monitored using non-invasive structural and molecular imaging optimized for renal tumors. Repetitive dual-contrast computed tomography (CT; intravenous and intraperitoneal contrast), T2-weighted magnetic resonance imaging (MRI), and delayed 2-deoxy-2-[(18)F]fluoro-D-glucose ((18)F-FDG) positron emission tomography (PET) were utilized for characterization of Igf2 biallelic expression/Wt1 knockout mouse model of Wilms tumor. For CT imaging, Ioversol 678 mg/ml in 200 μl was administered i.p. followed by 100 μl injected intravenously at 20 and 15 min prior to imaging, respectively. Static PET imaging studies were acquired at 1, 2, and 3 h after i.v. administration of (18)F-FDG (400 μCi). Coronal and sagittal T1-weighted images (TE/TR 8.5/620 ms) were acquired before and immediately after i.v. injection of 0.4 ml/kg gadopentetate dimeglumine followed by T2-weighted images (TE/TR 60/300 ms). Tumor tissue samples were characterized by histopathology and immunohistochemistry for Glut1, FASN, Ki67, and CD34. In addition, six Wt1-Igf2 mice were treated with a mitogen-activated protein kinase (MEK) inhibitor U0126 (50 μmol/kg i.p.) every 4 days for 6 weeks. (18)F-FDG PET/CT imaging was repeated at different days after initiation of therapy with U0126. The percent change of initial tumor volume and SUV was compared to non-treated historic control animals. Overall, the best tumor-to-adjacent kidney contrast as well as soft tissue contrast for other abdominal organs was achieved using T2-weighted MRI. Delayed (18)F-FDG PET (3-h post (18)F-FDG administration) and dual-contrast CT (intravenous and intraperitoneal contrast) provided a more accurate anatomic and metabolic characterization of Wilms tumors in Wt1-Igf2 mice

Osr1 Interacts Synergistically with Wt1 to Regulate Kidney Organogenesis.

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Jingyue Xu

Full Text Available Renal hypoplasia is a common cause of pediatric renal failure and several adult-onset diseases. Recent studies have associated a variant of the OSR1 gene with reduction of newborn kidney size and function in heterozygotes and neonatal lethality with kidney defects in homozygotes. How OSR1 regulates kidney development and nephron endowment is not well understood, however. In this study, by using the recently developed CRISPR genome editing technology, we genetically labeled the endogenous Osr1 protein and show that Osr1 interacts with Wt1 in the developing kidney. Whereas mice heterozygous for either an Osr1 or Wt1 null allele have normal kidneys at birth, most mice heterozygous for both Osr1 and Wt1 exhibit defects in metanephric kidney development, including unilateral or bilateral kidney agenesis or hypoplasia. The developmental defects in the Osr1+/-Wt1+/- mouse embryos were detected as early as E10.5, during specification of the metanephric mesenchyme, with the Osr1+/-Wt1+/- mouse embryos exhibiting significantly reduced Pax2-positive and Six2-positive nephron progenitor cells. Moreover, expression of Gdnf, the major nephrogenic signal for inducing ureteric bud outgrowth, was significantly reduced in the metanephric mesenchyme in Osr1+/-Wt1+/- embryos in comparison with the Osr1+/- or Wt1+/- littermates. By E11.5, as the ureteric buds invade the metanephric mesenchyme and initiate branching morphogenesis, kidney morphogenesis was significantly impaired in the Osr1+/-Wt1+/- embryos in comparison with the Osr1+/- or Wt1+/- embryos. These results indicate that Osr1 and Wt1 act synergistically to regulate nephron endowment by controlling metanephric mesenchyme specification during early nephrogenesis.

The progress of tumor gene-radiotherapy induced by Egr-1 promoter

International Nuclear Information System (INIS)

Guo Rui; Li Biao

2010-01-01

The promoter of early growth response gene-1 (Egr-1) is a cis-acting element of Egr-1, and its activity is regulated by inducers such as ionizing radiation, free radical. In designated gene-radiotherapy system, radiation combined with therapeutic gene (such as tumor necrosis factor-α gene, suicide gene) can spatially and temporally regulate therapeutic gene expression in the irradiated field, produced a marked effect, while little systemic toxicities were observed. The combination of radiotherapy and gene therapy is promising in tumor therapy. (authors)

Human Langerhans cells use an IL-15R-α/IL-15/pSTAT5-dependent mechanism to break T-cell tolerance against the self-differentiation tumor antigen WT1.

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Romano, Emanuela; Cotari, Jesse W; Barreira da Silva, Rosa; Betts, Brian C; Chung, David J; Avogadri, Francesca; Fink, Mitsu J; St Angelo, Erin T; Mehrara, Babak; Heller, Glenn; Münz, Christian; Altan-Bonnet, Gregoire; Young, James W

2012-05-31

Human CD34(+) progenitor-derived Langerhans-type dendritic cells (LCs) are more potent stimulators of T-cell immunity against tumor and viral antigens in vitro than are monocyte-derived DCs (moDCs). The exact mechanisms have remained elusive until now, however. LCs synthesize the highest amounts of IL-15R-α mRNA and protein, which binds IL-15 for presentation to responder lymphocytes, thereby signaling the phosphorylation of signal transducer and activator of transcription 5 (pSTAT5). LCs electroporated with Wilms tumor 1 (WT1) mRNA achieve sufficiently sustained presentation of antigenic peptides, which together with IL-15R-α/IL-15, break tolerance against WT1 by stimulating robust autologous, WT1-specific cytolytic T-lymphocytes (CTLs). These CTLs develop from healthy persons after only 7 days' stimulation without exogenous cytokines and lyse MHC-restricted tumor targets, which include primary WT1(+) leukemic blasts. In contrast, moDCs require exogenous rhuIL-15 to phosphorylate STAT5 and attain stimulatory capacity comparable to LCs. LCs therefore provide a more potent costimulatory cytokine milieu for T-cell activation than do moDCs, thus accounting for their superior stimulation of MHC-restricted Ag-specific CTLs without need for exogenous cytokines. These data support the use of mRNA-electroporated LCs, or moDCs supplemented with exogenous rhuIL-15, as vaccines for cancer immunotherapy to break tolerance against self-differentiation antigens shared by tumors.

Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context.

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Chiu, Hua-Sheng; Somvanshi, Sonal; Patel, Ektaben; Chen, Ting-Wen; Singh, Vivek P; Zorman, Barry; Patil, Sagar L; Pan, Yinghong; Chatterjee, Sujash S; Sood, Anil K; Gunaratne, Preethi H; Sumazin, Pavel

2018-04-03

Long noncoding RNAs (lncRNAs) are commonly dysregulated in tumors, but only a handful are known to play pathophysiological roles in cancer. We inferred lncRNAs that dysregulate cancer pathways, oncogenes, and tumor suppressors (cancer genes) by modeling their effects on the activity of transcription factors, RNA-binding proteins, and microRNAs in 5,185 TCGA tumors and 1,019 ENCODE assays. Our predictions included hundreds of candidate onco- and tumor-suppressor lncRNAs (cancer lncRNAs) whose somatic alterations account for the dysregulation of dozens of cancer genes and pathways in each of 14 tumor contexts. To demonstrate proof of concept, we showed that perturbations targeting OIP5-AS1 (an inferred tumor suppressor) and TUG1 and WT1-AS (inferred onco-lncRNAs) dysregulated cancer genes and altered proliferation of breast and gynecologic cancer cells. Our analysis indicates that, although most lncRNAs are dysregulated in a tumor-specific manner, some, including OIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergistically dysregulate cancer pathways in multiple tumor contexts. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Feasibility of Cancer Immunotherapy with WT1 Peptide Vaccination for Solid and Hematological Malignancies in Children.

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Sawada, Akihisa; Inoue, Masami; Kondo, Osamu; Yamada-Nakata, Kayo; Ishihara, Takashi; Kuwae, Yuko; Nishikawa, Masanori; Ammori, Yasuhiro; Tsuboi, Akihiro; Oji, Yusuke; Koyama-Sato, Maho; Oka, Yoshihiro; Yasui, Masahiro; Sugiyama, Haruo; Kawa, Keisei

2016-02-01

Advances in cancer immunotherapy in the pediatric field are needed in order to improve the prognosis of children with malignancies. We conducted a prospective phase I/II study of WT1 peptide vaccination for children with relapsed or refractory malignancies. The main eligibility criteria were affected tissues or leukemic cells expressing the WT1 gene, and patients (and donors for allogeneic hematopoietic stem cell transplantation) having HLA-A*24:02. Vaccination using the WT1 peptide (CYTWNQMNL), which was modified for higher affinity to this HLA-type molecule with the adjuvant Montanide ISA51, was performed weekly 12 times. Twenty-six patients were enrolled and 13 (50.0%) completed the vaccination 12 times. Evidence for the induction of WT1-specific cytotoxic T-lymphocyte (CTL) responses without severe systemic side effects was obtained. Two out of 12 patients with bulky disease exhibited a transient clinical effect (one mixed response and one stable disease), three out of six patients with minimal residual disease achieved transient molecular remission, and five out of eight patients without a detectable level of the molecular marker, but with a high risk of relapse, had the best outcome of long-term continuous complete remission. WT1 vaccination is a safe immunotherapy and induced WT1-specific CTL responses in children; however, as a single agent, vaccination only provided patients in remission, but with a high risk of relapse, with "long-term benefits" in the context of its use for relapse prevention. WT1 peptide-based treatments in combination with other modalities, such as anti-tumor drugs or immunomodulating agents, need to be planned. © 2015 Wiley Periodicals, Inc.

Expression of the tumor suppressor genes NF2, 4.1B, and TSLC1 in canine meningiomas.

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Dickinson, P J; Surace, E I; Cambell, M; Higgins, R J; Leutenegger, C M; Bollen, A W; LeCouteur, R A; Gutmann, D H

2009-09-01

Meningiomas are common primary brain tumors in dogs; however, little is known about the molecular genetic mechanisms involved in their tumorigenesis. Several tumor suppressor genes have been implicated in meningioma pathogenesis in humans, including the neurofibromatosis 2 (NF2), protein 4.1B (4.1 B), and tumor suppressor in lung cancer-1 (TSLC1) genes. We investigated the expression of these tumor suppressor genes in a series of spontaneous canine meningiomas using quantitative real-time reverse transcription polymerase chain reaction (RT-PCR) (NF2; n = 25) and western blotting (NF2/merlin, 4.1B, TSLC1; n = 30). Decreased expression of 4.1B and TSLC1 expression on western blotting was seen in 6/30 (20%) and in 15/30 (50%) tumors, respectively, with 18/30 (60%) of meningiomas having decreased or absent expression of one or both proteins. NF2 gene expression assessed by western blotting and RT-PCR varied considerably between individual tumors. Complete loss of NF2 protein on western blotting was not seen, unlike 4.1B and TSLC1. Incidence of TSLC1 abnormalities was similar to that seen in human meningiomas, while perturbation of NF2 and 4.1B appeared to be less common than reported for human tumors. No association was observed between tumor grade, subtype, or location and tumor suppressor gene expression based on western blot or RT-PCR. These results suggest that loss of these tumor suppressor genes is a frequent occurrence in canine meningiomas and may be an early event in tumorigenesis in some cases. In addition, it is likely that other, as yet unidentified, genes play an important role in canine meningioma formation and growth.

Wilms’ Tumor Blastemal Stem Cells Dedifferentiate to Propagate the Tumor Bulk

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Shukrun, Rachel; Pode-Shakked, Naomi; Pleniceanu, Oren; Omer, Dorit; Vax, Einav; Peer, Eyal; Pri-Chen, Sara; Jacob, Jasmine; Hu, Qianghua; Harari-Steinberg, Orit; Huff, Vicki; Dekel, Benjamin

2014-01-01

Summary An open question remains in cancer stem cell (CSC) biology whether CSCs are by definition at the top of the differentiation hierarchy of the tumor. Wilms’ tumor (WT), composed of blastema and differentiated renal elements resembling the nephrogenic zone of the developing kidney, is a valuable model for studying this question because early kidney differentiation is well characterized. WT neural cell adhesion molecule 1-positive (NCAM1+) aldehyde dehydrogenase 1-positive (ALDH1+) CSCs have been recently isolated and shown to harbor early renal progenitor traits. Herein, by generating pure blastema WT xenografts, composed solely of cells expressing the renal developmental markers SIX2 and NCAM1, we surprisingly show that sorted ALDH1+ WT CSCs do not correspond to earliest renal stem cells. Rather, gene expression and proteomic comparative analyses disclose a cell type skewed more toward epithelial differentiation than the bulk of the blastema. Thus, WT CSCs are likely to dedifferentiate to propagate WT blastema. PMID:25068119

Clinically Relevant Subsets Identified by Gene Expression Patterns Support a Revised Ontogenic Model of Wilms Tumor: A Children's Oncology Group Study

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Samantha Gadd

2012-08-01

Full Text Available Wilms tumors (WT have provided broad insights into the interface between development and tumorigenesis. Further understanding is confounded by their genetic, histologic, and clinical heterogeneity, the basis of which remains largely unknown. We evaluated 224 WT for global gene expression patterns; WT1, CTNNB1, and WTX mutation; and 11p15 copy number and methylation patterns. Five subsets were identified showing distinct differences in their pathologic and clinical features: these findings were validated in 100 additional WT. The gene expression pattern of each subset was compared with published gene expression profiles during normal renal development. A novel subset of epithelial WT in infants lacked WT1, CTNNB1, and WTX mutations and nephrogenic rests and displayed a gene expression pattern of the postinduction nephron, and none recurred. Three subsets were characterized by a low expression of WT1 and intralobar nephrogenic rests. These differed in their frequency of WT1 and CTNNB1 mutations, in their age, in their relapse rate, and in their expression similarities with the intermediate mesoderm versus the metanephric mesenchyme. The largest subset was characterized by biallelic methylation of the imprint control region 1, a gene expression profile of the metanephric mesenchyme, and both interlunar and perilobar nephrogenic rests. These data provide a biologic explanation for the clinical and pathologic heterogeneity seen within WT and enable the future development of subset-specific therapeutic strategies. Further, these data support a revision of the current model of WT ontogeny, which allows for an interplay between the type of initiating event and the developmental stage in which it occurs.

Effect of superimposed low frequency oscillations on the static creep behaviour of Al-1 wt%Si and Al-1 wt%Si-0.1 wt%Zr-0.1 wt%Ti alloys

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Beshai, M.H.N. [Ain Shams Univ., Cairo (Egypt). Dept. of Physics; Deaf, G.H. [Ain Shams Univ., Cairo (Egypt). Dept. of Physics; Abd El Khalek, A.M. [Ain Shams Univ., Cairo (Egypt). Dept. of Physics; Graiss, G. [Ain Shams Univ., Cairo (Egypt). Dept. of Physics; Kenawy, M.A. [Physics Dept., University Coll. for Women, Ain Shams Univ., Cairo (Egypt)

1997-05-16

Torsional oscillations of increasing frequencies with constant torsional strain amplitude, {theta}, of 3.1 x 10{sup -4} were superimposed on wires of Al-1 wt% Si and Al-1 wt% Si-0.1 wt% Zr-0.1 wt% Ti alloys, while being crept under constant stress (52.3 MPa) and different testing temperatures. It was found that increasing the frequency of oscillations resulted in an increase of both transient and steady state creep. In the transient stage, while the exponent n is increasing with frequency v, the parameter {beta} decreases. Zirconium and titanium addition generally reduced the rate of creep. A value of 20 kJ/mol was found for the activation energy of the mechanism operating in the transient and steady state stages which was ascribed as being due to dislocation intersection. (orig.)

Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context

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Hua-Sheng Chiu

2018-04-01

Full Text Available Summary: Long noncoding RNAs (lncRNAs are commonly dysregulated in tumors, but only a handful are known to play pathophysiological roles in cancer. We inferred lncRNAs that dysregulate cancer pathways, oncogenes, and tumor suppressors (cancer genes by modeling their effects on the activity of transcription factors, RNA-binding proteins, and microRNAs in 5,185 TCGA tumors and 1,019 ENCODE assays. Our predictions included hundreds of candidate onco- and tumor-suppressor lncRNAs (cancer lncRNAs whose somatic alterations account for the dysregulation of dozens of cancer genes and pathways in each of 14 tumor contexts. To demonstrate proof of concept, we showed that perturbations targeting OIP5-AS1 (an inferred tumor suppressor and TUG1 and WT1-AS (inferred onco-lncRNAs dysregulated cancer genes and altered proliferation of breast and gynecologic cancer cells. Our analysis indicates that, although most lncRNAs are dysregulated in a tumor-specific manner, some, including OIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergistically dysregulate cancer pathways in multiple tumor contexts. : Chiu et al. present a pan-cancer analysis of lncRNA regulatory interactions. They suggest that the dysregulation of hundreds of lncRNAs target and alter the expression of cancer genes and pathways in each tumor context. This implies that hundreds of lncRNAs can alter tumor phenotypes in each tumor context. Keywords: lncRNA, regulation, modulation, cancer gene, pan-cancer, noncoding RNA, microRNA, RNA-binding proteins, interactome

Tumor necrosis factor-alpha-independent downregulation of hepatic cholesterol 7alpha-hydroxylase gene in mice treated with lead nitrate.

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Kojima, Misaki; Sekikawa, Kenji; Nemoto, Kiyomitsu; Degawa, Masakuni

2005-10-01

We previously reported that lead nitrate (LN), an inducer of hepatic tumor necrosis factor-alpha (TNF-alpha), downregulated gene expression of cholesterol 7alpha-hydroxylase. Herein, to clarify the role of TNF-alpha in LN-induced downregulation of cholesterol 7alpha-hydroxylase, effects of LN on gene expression of hepatic cholesterol 7alpha-hydroxylase (Cyp7a1) in TNF-alpha-knockout (KO) and TNF-alpha-wild-type (WT) mice were comparatively examined. Gene expression of hepatic Cyp7a1 in both WT and KO mice decreased to less than 5% of the corresponding controls at 6-12 h after treatment with LN (100 mumol/kg body weight, iv). Levels of hepatic TNF-alpha protein in either WT or KO mice were below the detection limit, although expression levels of the TNF-alpha gene markedly increased at 6 h in WT mice by LN treatment, but not in KO mice. In contrast, in both WT and KO mice, levels of hepatic IL-1beta protein, which is known to be a suppressor of the cholesterol 7alpha-hydroxylase gene in hamsters, were significantly increased 3-6 h after LN treatment. Furthermore, LN-induced downregulation of the Cyp7a1 gene did not necessarily result from altered gene expression of hepatic transcription factors, including positive regulators (liver X receptor alpha, retinoid X receptor alpha, fetoprotein transcription factor, and hepatocyte nuclear factor 4alpha) and a negative regulator small heterodimer partner responsible for expression of the Cyp7a1 gene. The present findings indicated that LN-induced downregulation of the Cyp7a1 gene in mice did not necessarily occur through a TNF-alpha-dependent pathway and might occur mainly through an IL-1beta-dependent pathway.

The inflammatory cytokine TNFα cooperates with Ras in elevating metastasis and turns WT-Ras to a tumor-promoting entity in MCF-7 cells

International Nuclear Information System (INIS)

Leibovich-Rivkin, Tal; Liubomirski, Yulia; Meshel, Tsipi; Abashidze, Anastasia; Brisker, Daphna; Solomon, Hilla; Rotter, Varda; Weil, Miguel; Ben-Baruch, Adit

2014-01-01

In the present study we determined the relative contribution of two processes to breast cancer progression: (1) Intrinsic events, such as activation of the Ras pathway and down-regulation of p53; (2) The inflammatory cytokines TNFα and IL-1β, shown in our published studies to be highly expressed in tumors of >80% of breast cancer patients with recurrent disease. Using MCF-7 human breast tumor cells originally expressing WT-Ras and WT-p53, we determined the impact of the above-mentioned elements and cooperativity between them on the expression of CXCL8 (ELISA, qRT-PCR), a member of a “cancer-related chemokine cluster” that we have previously identified. Then, we determined the mechanisms involved (Ras-binding-domain assays, Western blot, luciferase), and tested the impact of Ras + TNFα on angiogenicity (chorioallantoic membrane assays) and on tumor growth at the mammary fat pad of mice and on metastasis, in vivo. Using Ras G12V that recapitulates multiple stimulations induced by receptor tyrosine kinases, we found that Ras G12V alone induced CXCL8 expression at the mRNA and protein levels, whereas down-regulation of p53 did not. TNFα and IL-1β potently induced CXCL8 expression and synergized with Ras G12V , together leading to amplified CXCL8 expression. Testing the impact of WT-Ras, which is the common form in breast cancer patients, we found that WT-Ras was not active in promoting CXCL8; however, TNFα has induced the activation of WT-Ras: joining these two elements has led to cooperative induction of CXCL8 expression, via the activation of MEK, NF-κB and AP-1. Importantly, TNFα has led to increased expression of WT-Ras in an active GTP-bound form, with properties similar to those of Ras G12V . Jointly, TNFα + Ras activities have given rise to increased angiogenesis and to elevated tumor cell dissemination to lymph nodes. TNFα cooperates with Ras in promoting the metastatic phenotype of MCF-7 breast tumor cells, and turns WT-Ras into a tumor

[Correlation analysis of G870A CCND1 gene polymorphism with digestive system tumors].

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Yang, Shu-Min; Shi, Ya-Lin

2016-11-20

To study the correlation of G870A CCND1 gene polymorphism and digestive system tumors. From August 2010 to August 2014, 164 digestive system cancer patients (including 82 patients with gastric cancer and 82 with colorectal cancer) and 82 healthy subjects (control group) were examined with PCR-restriction fragment length polymorphism (PCR-RFLP). The distribution of CCND1 gene G870A frequency in the 3 groups and its association with tumor staging and grading were analyzed. The frequencies of the GG, GA and AA genotypes in G870A CCND1 gene loci in patients with gastric cancer and colorectal cancer differed significantly from those in the control group (Pdigestive system tumors (Pdigestive system cancer risk than the GG genotype (Pdigestive system tumors. The allele A is associated with an increased risk of digestive system tumors and correlated with the tumor differentiation and staging of the tumor.

Anaplasia and drug selection-independent overexpression of the multidrug resistance gene, MDR1, in Wilms' tumor.

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Re, G G; Willingham, M C; el Bahtimi, R; Brownlee, N A; Hazen-Martin, D J; Garvin, A J

1997-02-01

One reason for the failure of chemotherapy is the overexpression of the multidrug resistance gene, MDR1. The product of this gene is the multidrug transporter P-glycoprotein, an ATP-dependent pump that extrudes drugs from the cytoplasm. Some tumors inherently express P-glycoprotein, whereas others acquire the ability to do so after exposure to certain chemotherapeutic agents, often by the mechanism of gene amplification. Classical Wilms' tumors (nephroblastoma) typically respond to therapy and have a good prognosis. On the contrary, anaplastic Wilms' tumors are generally refractory to chemotherapy. These anaplastic variants are rare (4.5% of all Wilms' tumors reported in the United States), aggressive, and often fatal forms of tumor, which are commonly thought to result from the progression of classical Wilms' tumors. To investigate the basis for this differential response to therapy, we examined a number of classical and anaplastic Wilms' tumors for the expression of the MDR1 gene by immunohistochemical and mRNA analysis. Classical Wilms' tumors consistently did not express P-glycoprotein except in areas of tubular differentiation, as in normal kidney. Similarly, two of three anaplastic tumors failed to show P-glycoprotein expression. In contrast, cultured cells derived from a third anaplastic tumor, W4, exhibited strong P-glycoprotein expression and were drug resistant in vitro. Southern analysis revealed that W4 cells contained a single copy of the MDR1 gene per haploid genome similar to normal cells, demonstrating that the overexpression of MDR1 was not caused by gene amplification. Transcriptional activation of the MDR1 gene would be in keeping with the concept that p53 might act as a transcriptional repressor of the MDR1 gene.

Wilms’ Tumor 1 Gene Mutations Independently Predict Poor Outcome in Adults With Cytogenetically Normal Acute Myeloid Leukemia: A Cancer and Leukemia Group B Study

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Paschka, Peter; Marcucci, Guido; Ruppert, Amy S.; Whitman, Susan P.; Mrózek, Krzysztof; Maharry, Kati; Langer, Christian; Baldus, Claudia D.; Zhao, Weiqiang; Powell, Bayard L.; Baer, Maria R.; Carroll, Andrew J.; Caligiuri, Michael A.; Kolitz, Jonathan E.; Larson, Richard A.; Bloomfield, Clara D.

2008-01-01

Purpose To analyze the prognostic impact of Wilms’ tumor 1 (WT1) gene mutations in cytogenetically normal acute myeloid leukemia (CN-AML). Patients and Methods We studied 196 adults younger than 60 years with newly diagnosed primary CN-AML, who were treated similarly on Cancer and Leukemia Group B (CALGB) protocols 9621 and 19808, for WT1 mutations in exons 7 and 9. The patients also were assessed for the presence of FLT3 internal tandem duplications (FLT3-ITD), FLT3 tyrosine kinase domain mutations (FLT3-TKD), MLL partial tandem duplications (MLL-PTD), NPM1 and CEBPA mutations, and for the expression levels of ERG and BAALC. Results Twenty-one patients (10.7%) harbored WT1 mutations. Complete remission rates were not significantly different between patients with WT1 mutations and those with unmutated WT1 (P = .36; 76% v 84%). Patients with WT1 mutations had worse disease-free survival (DFS; P < .001; 3-year rates, 13% v 50%) and overall survival (OS; P < .001; 3-year rates, 10% v 56%) than patients with unmutated WT1. In multivariable analyses, WT1 mutations independently predicted worse DFS (P = .009; hazard ratio [HR] = 2.7) when controlling for CEBPA mutational status, ERG expression level, and FLT3-ITD/NPM1 molecular-risk group (ie, FLT3-ITDnegative/NPM1mutated as low risk v FLT3-ITDpositive and/or NPM1wild-type as high risk). WT1 mutations also independently predicted worse OS (P < .001; HR = 3.2) when controlling for CEBPA mutational status, FLT3-ITD/NPM1 molecular-risk group, and white blood cell count. Conclusion We report the first evidence that WT1 mutations independently predict extremely poor outcome in intensively treated, younger patients with CN-AML. Future trials should include testing for WT1 mutations as part of molecularly based risk assessment and risk-adapted treatment stratification of patients with CN-AML. PMID:18559874

Wilms Tumor 1b defines a wound-specific sheath cell subpopulation associated with notochord repair

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Lopez-Baez, Juan Carlos; Zeng, Zhiqiang; Brunsdon, Hannah; Salzano, Angela; Brombin, Alessandro; Wyatt, Cameron; Rybski, Witold; Huitema, Leonie F A; Dale, Rodney M; Kawakami, Koichi; Englert, Christoph; Chandra, Tamir; Schulte-Merker, Stefan

2018-01-01

Regenerative therapy for degenerative spine disorders requires the identification of cells that can slow down and possibly reverse degenerative processes. Here, we identify an unanticipated wound-specific notochord sheath cell subpopulation that expresses Wilms Tumor (WT) 1b following injury in zebrafish. We show that localized damage leads to Wt1b expression in sheath cells, and that wt1b+cells migrate into the wound to form a stopper-like structure, likely to maintain structural integrity. Wt1b+sheath cells are distinct in expressing cartilage and vacuolar genes, and in repressing a Wt1b-p53 transcriptional programme. At the wound, wt1b+and entpd5+ cells constitute separate, tightly-associated subpopulations. Surprisingly, wt1b expression at the site of injury is maintained even into adult stages in developing vertebrae, which form in an untypical manner via a cartilage intermediate. Given that notochord cells are retained in adult intervertebral discs, the identification of novel subpopulations may have important implications for regenerative spine disorder treatments. PMID:29405914

Early Death in Two Patients with Acute Promyelocytic Leukemia Presenting the bcr3 Isoform, FLT3-ITD Mutation, and Elevated WT1 Level

Directory of Open Access Journals (Sweden)

Marianna Greco

2013-01-01

Full Text Available Despite major advances in the treatment of acute promyelocytic leukemia (APL, the problem of early death (ED remains unsolved. Alongside the currently known clinical and hematological risk factors, prognostic significance has been attributed to internal tandem duplication mutations of the fms-like tyrosine kinase-3 (FLT3-ITD, hypogranular variant morphology, and the bcr-3 isoform of PML-RARα. We describe premature death of two patients with the hypogranular variant of APL who presented remarkably high expression levels of Wilms' tumor gene (WT1. Our results point to WT1 as an important prognostic factor of ED that needs to be promptly evaluated in all newly diagnosed cases of APL.

Evidence that WT1 mutations in Denys-Drash syndrome patients may act in a dominant-negative fashion

NARCIS (Netherlands)

Little, M. H.; Williamson, K. A.; Mannens, M.; Kelsey, A.; Gosden, C.; Hastie, N. D.; van Heyningen, V.

1993-01-01

The triad of nephropathy, partial gonadal dysgenesis and Wilms' tumour (WT) is known as Denys-Drash syndrome (DDS). The WT predisposition gene WT1, which plays a vital role in both genital and renal development, is known to be mutated in DDS patients. The WT1 mutations in these patients are

Analysis list: Wt1 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Wt1 Embryo,Kidney + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Wt1.1....tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Wt1.5.tsv http://dbarchive.biosciencedbc.jp/kyush...u-u/mm9/target/Wt1.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Wt1.Embryo.tsv,http://dbarchive.bioscience...dbc.jp/kyushu-u/mm9/colo/Wt1.Kidney.tsv http://dbarchive.biosciencedb...c.jp/kyushu-u/mm9/colo/Embryo.gml,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Kidney.gml ...

Tumor targeted gene therapy

International Nuclear Information System (INIS)

Kang, Joo Hyun

2006-01-01

Knowledge of molecular mechanisms governing malignant transformation brings new opportunities for therapeutic intervention against cancer using novel approaches. One of them is gene therapy based on the transfer of genetic material to an organism with the aim of correcting a disease. The application of gene therapy to the cancer treatment had led to the development of new experimental approaches such as suicidal gene therapy, inhibition of oncogenes and restoration of tumor-suppressor genes. Suicidal gene therapy is based on the expression in tumor cells of a gene encoding an enzyme that converts a prodrug into a toxic product. Representative suicidal genes are Herpes simplex virus type 1 thymidine kinase (HSV1-tk) and cytosine deaminase (CD). Especially, physicians and scientists of nuclear medicine field take an interest in suicidal gene therapy because they can monitor the location and magnitude, and duration of expression of HSV1-tk and CD by PET scanner

Simultaneous analysis of the expression of 14 genes with individual prognostic value in myelodysplastic syndrome patients at diagnosis: WT1 detection in peripheral blood adversely affects survival.

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Santamaría, Carlos; Ramos, Fernando; Puig, Noemi; Barragán, Eva; de Paz, Raquel; Pedro, Carme; Insunza, Andrés; Tormo, Mar; Del Cañizo, Consuelo; Diez-Campelo, María; Xicoy, Blanca; Salido, Eduardo; Sánchez del Real, Javier; Hernández, Montserrat; Chillón, Carmen; Sanz, Guillermo F; García-Sanz, Ramón; San Miguel, Jesús F; González, Marcos

2012-12-01

Several studies have evaluated the prognostic value of the individual expression of certain genes in patients with myelodysplastic syndromes (MDS). However, none of them includes their simultaneous analysis by quantitative polymerase chain reaction (PCR). We evaluated relative expression levels of 14 molecular markers in 193 peripheral blood samples from untreated MDS patients using real-time PCR. Detectable WT1 expression levels, low TET2, and low IER3 gene expression were the only markers showing in univariate analysis a poor prognostic value for all treatment-free (TFS), progression-free (PFS), and overall survival (OS). In multivariate analysis, molecular parameters associated with a shorter TFS were: WT1 detection (p = 0.014), low TET2 (p = 0.002), and low IER3 expression (p = 0.025). WT1 detection (p = 0.006) and low TET2 (p = 0.006) expression were associated with a shorter PFS when multivariate analysis was carried out by including only molecular markers. Molecular values with an independent value in OS were: WT1 detection (p = 0.003), high EVI1 expression (p = 0.001), and undetectatable p15-CDKN2B (p = 0.037). WT1 expressers were associated with adverse clinical-biological features, high IPSS and WPSS scoring, and unfavorable molecular expression profile. In summary, detectable WT1 expression levels, and low TET2 and low IER3 expression in peripheral blood showed a strong association with adverse prognosis in MDS patients at diagnosis. However, WT1 was the only molecular marker displaying an independent prognostic value in both OS and TFS.

Analysis of SNP rs16754 of WT1 gene in a series of de novo acute myeloid leukemia patients.

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Luna, Irene; Such, Esperanza; Cervera, Jose; Barragán, Eva; Jiménez-Velasco, Antonio; Dolz, Sandra; Ibáñez, Mariam; Gómez-Seguí, Inés; López-Pavía, María; Llop, Marta; Fuster, Óscar; Oltra, Silvestre; Moscardó, Federico; Martínez-Cuadrón, David; Senent, M Leonor; Gascón, Adriana; Montesinos, Pau; Martín, Guillermo; Bolufer, Pascual; Sanz, Miguel A

2012-12-01

The single nucleotide polymorphism (SNP) rs16754 of the WT1 gene has been previously described as a possible prognostic marker in normal karyotype acute myeloid leukemia (AML) patients. Nevertheless, the findings in this field are not always reproducible in different series. One hundred and seventy-five adult de novo AML patients were screened with two different methods for the detection of SNP rs16754: high-resolution melting (HRM) and FRET hybridization probes. Direct sequencing was used to validate both techniques. The SNP was detected in 52 out of 175 patients (30 %), both by HRM and hybridization probes. Direct sequencing confirmed that every positive sample in the screening methods had a variation in the DNA sequence. Patients with the wild-type genotype (WT1(AA)) for the SNP rs16754 were significantly younger than those with the heterozygous WT1(AG) genotype. No other difference was observed for baseline characteristic or outcome between patients with or without the SNP. Both techniques are equally reliable and reproducible as screening methods for the detection of the SNP rs16754, allowing for the selection of those samples that will need to be sequenced. We were unable to confirm the suggested favorable outcome of SNP rs16754 in de novo AML.

Genetic and epigenetic silencing of the beclin 1 gene in sporadic breast tumors

International Nuclear Information System (INIS)

Li, Zidong; Chen, Bo; Wu, Yiqing; Jin, Feng; Xia, Yongjing; Liu, Xiangjun

2010-01-01

Beclin 1, an important autophagy-related protein in human cells, is involved in cell death and cell survival. Beclin 1 mapped to human chromosome 17q21. It is widely expressed in normal mammary epithelial cells. Although down-regulated expression with mono-allelic deletions of beclin 1 gene was frequently observed in breast tumors, whether there was other regulatory mechanism of beclin 1 was to be investigated. We studied the expression of beclin 1 and explored the possible regulatory mechanisms on its expression in breast tumors. 20 pairs of tumors and adjacent normal tissues from patients with sporadic breast invasive ductal cancer (IDCs) were collected. The mRNA expression of beclin 1 was detected by real-time quantitative RT-PCR. Loss of heterozygosity (LOH) was determined by real-time quantitative PCR and microsatellite methods. The protein expression of beclin 1, p53, BRCA1 and BRCA2 was assessed by immunohistochemistry. CpG islands in 5' genomic region of beclin 1 gene were identified using MethylPrimer Program. Sodium bisulfite sequencing was used in examining the methylation status of each CpG island. Decreased beclin 1 mRNA expression was detected in 70% of the breast tumors, and the protein levels were co-related to the mRNA levels. Expression of beclin 1 mRNA was demonstrated to be much higher in the BRCA1 positive tumors than that in the BRCA1 negative ones. Loss of heterozygosity was detected in more than 45% of the breast tumors, and a dense cluster of CpG islands was found from the 5' end to the intron 2 of the beclin 1 gene. Methylation analysis showed that the promoter and the intron 2 of beclin 1 were aberrantly methylated in the tumors with decreased expression. These data indicated that LOH and aberrant DNA methylation might be the possible reasons of the decreased expression of beclin 1 in the breast tumors. The findings here shed some new light on the regulatory mechanisms of beclin 1 in breast cancer

Tissue expression of MLH1, PMS2, MSH2, and MSH6 proteins and prognostic value of microsatellite instability in Wilms tumor: experience of 45 cases.

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Diniz, Gulden; Aktas, Safiye; Cubuk, Cankut; Ortac, Ragip; Vergin, Canan; Olgun, Nur

2013-05-01

Although the importance of microsatellite instability (MSI) and mismatch repair genes (MMR) is strongly established in colorectal cancer seen in the Lynch syndrome, its significance has not been fully established in Wilms tumor (WT). The aim of this study was to determine the prognostic value of MSI and MMR proteins in WT. This study included 45 pediatric cases with nephroblastoma. Protein expression was analyzed by immunohistochemistry of archival tissue sections. Real-time PCR melting analysis and fluorescence capillary electrophoresis (FCE) were performed to evaluate the MSI markers BAT25, BAT26, NR21, NR24, MONO27, penta D, and penta C in DNA extracted from tumor and normal tissues. Lower levels of MSI were observed in six cases (13.3%). There were no statistically significant correlations between MSI and some clinical prognostic factors such as stage of the tumors, and survival rates. Nineteen tumors (42.2%) showed loss of protein expression of MLH1, PMS2, MSH2, or MSH6. MMR protein defects were correlated with size (P = .021), and stage (P = .019) of the tumor, and survival rates (P < .01).Similarly MSI was also correlated with the size of the tumor (P = .046). This study showed that a small proportion of WT might be associated with the presence of MSI, as is the case with defects of DNA mismatch repair genes in the pathogenesis of WT. However, there was no concordance with the frequency of tissue expression of MMR proteins and MSI. These findings suggest that MMR genes may play an important role in the development of WT via different pathways.

Tumor-produced, active Interleukin-1 β regulates gene expression in carcinoma-associated fibroblasts

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Dudas, Jozsef; Fullar, Alexandra; Bitsche, Mario; Schartinger, Volker; Kovalszky, Ilona; Sprinzl, Georg Mathias; Riechelmann, Herbert

2011-01-01

Recently we described a co-culture model of periodontal ligament (PDL) fibroblasts and SCC-25 lingual squamous carcinoma cells, which resulted in conversion of normal fibroblasts into carcinoma-associated fibroblasts (CAFs), and in epithelial-mesenchymal transition (EMT) of SCC-25 cells. We have found a constitutive high interleukin-1β (IL1-β) expression in SCC-25 cells in normal and in co-cultured conditions. In our hypothesis a constitutive IL1-β expression in SCC-25 regulates gene expression in fibroblasts during co-culture. Co-cultures were performed between PDL fibroblasts and SCC-25 cells with and without dexamethasone (DEX) treatment; IL1-β processing was investigated in SCC-25 cells, tumor cells and PDL fibroblasts were treated with IL1-β. IL1-β signaling was investigated by western blot and immunocytochemistry. IL1-β-regulated genes were analyzed by real-time qPCR. SCC-25 cells produced 16 kD active IL1-β, its receptor was upregulated in PDL fibroblasts during co-culture, which induced phosphorylation of interleukin-1 receptor-associated kinase-1 (IRAK-1), and nuclear translocalization of NFκBα. Several genes, including interferon regulatory factor 1 (IRF1) interleukin-6 (IL-6) and prostaglandin-endoperoxide synthase 2 (COX-2) were induced in CAFs during co-culture. The most enhanced induction was found for IL-6 and COX-2. Treatment of PDL fibroblasts with IL1-β reproduced a time- and dose-dependent upregulation of IL1-receptor, IL-6 and COX-2. A further proof was achieved by DEX inhibition for IL1-β-stimulated IL-6 and COX-2 gene expression. Constitutive expression of IL1-β in the tumor cells leads to IL1-β-stimulated gene expression changes in tumor-associated fibroblasts, which are involved in tumor progression. -- Graphical abstract: SCC-25 cells produce active, processed IL1-β. PDL fibroblasts possess receptor for IL1-β, and its expression is increased 4.56-times in the presence of SCC-25 tumor cells. IL1-β receptor expression in

Tumor-produced, active Interleukin-1 {beta} regulates gene expression in carcinoma-associated fibroblasts

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Dudas, Jozsef, E-mail: Jozsef.Dudas@i-med.ac.at [Department of Otorhinolaryngology, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Fullar, Alexandra, E-mail: fullarsz@gmail.com [Department of Otorhinolaryngology, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); 1st Institute of Pathology and Experimental Cancer Research, Semmelweis University, Ulloei ut 26, H-1085 Budapest (Hungary); Bitsche, Mario, E-mail: Mario.Bitsche@i-med.ac.at [Department of Otorhinolaryngology, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Schartinger, Volker, E-mail: Volker.Schartinger@i-med.ac.at [Department of Otorhinolaryngology, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Kovalszky, Ilona, E-mail: koval@korb1.sote.hu [1st Institute of Pathology and Experimental Cancer Research, Semmelweis University, Ulloei ut 26, H-1085 Budapest (Hungary); Sprinzl, Georg Mathias, E-mail: Georg.Sprinzl@i-med.ac.at [Department of Otorhinolaryngology, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Riechelmann, Herbert, E-mail: Herbert.Riechelmann@i-med.ac.at [Department of Otorhinolaryngology, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria)

2011-09-10

Recently we described a co-culture model of periodontal ligament (PDL) fibroblasts and SCC-25 lingual squamous carcinoma cells, which resulted in conversion of normal fibroblasts into carcinoma-associated fibroblasts (CAFs), and in epithelial-mesenchymal transition (EMT) of SCC-25 cells. We have found a constitutive high interleukin-1{beta} (IL1-{beta}) expression in SCC-25 cells in normal and in co-cultured conditions. In our hypothesis a constitutive IL1-{beta} expression in SCC-25 regulates gene expression in fibroblasts during co-culture. Co-cultures were performed between PDL fibroblasts and SCC-25 cells with and without dexamethasone (DEX) treatment; IL1-{beta} processing was investigated in SCC-25 cells, tumor cells and PDL fibroblasts were treated with IL1-{beta}. IL1-{beta} signaling was investigated by western blot and immunocytochemistry. IL1-{beta}-regulated genes were analyzed by real-time qPCR. SCC-25 cells produced 16 kD active IL1-{beta}, its receptor was upregulated in PDL fibroblasts during co-culture, which induced phosphorylation of interleukin-1 receptor-associated kinase-1 (IRAK-1), and nuclear translocalization of NF{kappa}B{alpha}. Several genes, including interferon regulatory factor 1 (IRF1) interleukin-6 (IL-6) and prostaglandin-endoperoxide synthase 2 (COX-2) were induced in CAFs during co-culture. The most enhanced induction was found for IL-6 and COX-2. Treatment of PDL fibroblasts with IL1-{beta} reproduced a time- and dose-dependent upregulation of IL1-receptor, IL-6 and COX-2. A further proof was achieved by DEX inhibition for IL1-{beta}-stimulated IL-6 and COX-2 gene expression. Constitutive expression of IL1-{beta} in the tumor cells leads to IL1-{beta}-stimulated gene expression changes in tumor-associated fibroblasts, which are involved in tumor progression. -- Graphical abstract: SCC-25 cells produce active, processed IL1-{beta}. PDL fibroblasts possess receptor for IL1-{beta}, and its expression is increased 4.56-times in the

Mice lacking pituitary tumor transforming gene show elevated exposure of DGalNAc carbohydrate determinants

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Lutsyk A. D.

2012-04-01

Full Text Available Aim. To investigate the influence of pituitary tumor transforming gene (pttg-1 knockout on glycome of parenchimal organs by means of lectin histochemistry. Methods. DGalNAc, DGlcNAc, NeuNAc carbohydrate determinants were labelled with soybean agglutinin (SBA and wheat germ agglutinin (WGA, conjugated to peroxidase, with subsequent visualization of the lectin-binding sites with diaminobenzidine. The testes and kidneys of murine strain BL6/C57 with the pttg-1 gene knockout (PTTG-KO were compared to the wild type (PTTG-WT animals, both groups 1 month of age. Results. Knockout of the pttg-1 gene was accompanied by enhanced exposure of the DGalNAc sugar residues within the Golgi complex of secondary spermatocytes, in a brush border of renal tubules and on the lumenal surface of collecting ducts. Conclusions. This study suggests that knockout of the pttg-1 gene may lead to the changes in carbohydrate processing in mammalian organism.

Transcriptomic characterization of MRI contrast with focus on the T1-w/T2-w ratio in the cerebral cortex.

Science.gov (United States)

Ritchie, Jacob; Pantazatos, Spiro P; French, Leon

2018-07-01

Magnetic resonance (MR) images of the brain are of immense clinical and research utility. At the atomic and subatomic levels, the sources of MR signals are well understood. However, we lack a comprehensive understanding of the macromolecular correlates of MR signal contrast. To address this gap, we used genome-wide measurements to correlate gene expression with MR signal intensity across the cerebral cortex in the Allen Human Brain Atlas (AHBA). We focused on the ratio of T1-weighted and T2-weighted intensities (T1-w/T2-w ratio image), which is considered to be a useful proxy for myelin content. As expected, we found enrichment of positive correlations between myelin-associated genes and the ratio image, supporting its use as a myelin marker. Genome-wide, there was an association with protein mass, with genes coding for heavier proteins expressed in regions with high T1-w/T2-w values. Oligodendrocyte gene markers were strongly correlated with the T1-w/T2-w ratio, but this was not driven by myelin-associated genes. Mitochondrial genes exhibit the strongest relationship, showing higher expression in regions with low T1-w/T2-w ratio. This may be due to the pH gradient in mitochondria as genes up-regulated by pH in the brain were also highly correlated with the ratio. While we corroborate associations with myelin and synaptic plasticity, differences in the T1-w/T2-w ratio across the cortex are more strongly linked to molecule size, oligodendrocyte markers, mitochondria, and pH. We evaluate correlations between AHBA transcriptomic measurements and a group averaged T1-w/T2-w ratio image, showing agreement with in-sample results. Expanding our analysis to the whole brain results in strong positive T1-w/T2-w correlations for immune system, inflammatory disease, and microglia marker genes. Genes with negative correlations were enriched for neuron markers and synaptic plasticity genes. Lastly, our findings are similar when performed on T1-w or inverted T2-w intensities alone

Analysis of gene expression in prostate cancer epithelial and interstitial stromal cells using laser capture microdissection

International Nuclear Information System (INIS)

Gregg, Jennifer L; Brown, Kathleen E; Mintz, Eric M; Piontkivska, Helen; Fraizer, Gail C

2010-01-01

The prostate gland represents a multifaceted system in which prostate epithelia and stroma have distinct physiological roles. To understand the interaction between stroma and glandular epithelia, it is essential to delineate the gene expression profiles of these two tissue types in prostate cancer. Most studies have compared tumor and normal samples by performing global expression analysis using a mixture of cell populations. This report presents the first study of prostate tumor tissue that examines patterns of differential expression between specific cell types using laser capture microdissection (LCM). LCM was used to isolate distinct cell-type populations and identify their gene expression differences using oligonucleotide microarrays. Ten differentially expressed genes were then analyzed in paired tumor and non-neoplastic prostate tissues by quantitative real-time PCR. Expression patterns of the transcription factors, WT1 and EGR1, were further compared in established prostate cell lines. WT1 protein expression was also examined in prostate tissue microarrays using immunohistochemistry. The two-step method of laser capture and microarray analysis identified nearly 500 genes whose expression levels were significantly different in prostate epithelial versus stromal tissues. Several genes expressed in epithelial cells (WT1, GATA2, and FGFR-3) were more highly expressed in neoplastic than in non-neoplastic tissues; conversely several genes expressed in stromal cells (CCL5, CXCL13, IGF-1, FGF-2, and IGFBP3) were more highly expressed in non-neoplastic than in neoplastic tissues. Notably, EGR1 was also differentially expressed between epithelial and stromal tissues. Expression of WT1 and EGR1 in cell lines was consistent with these patterns of differential expression. Importantly, WT1 protein expression was demonstrated in tumor tissues and was absent in normal and benign tissues. The prostate represents a complex mix of cell types and there is a need to analyze

Gene expression in tumor cells and stroma in dsRed 4T1 tumors in eGFP-expressing mice with and without enhanced oxygenation

International Nuclear Information System (INIS)

Moen, Ingrid; Øyan, Anne M; Stuhr, Linda EB; Jevne, Charlotte; Wang, Jian; Kalland, Karl-Henning; Chekenya, Martha; Akslen, Lars A; Sleire, Linda; Enger, Per Ø; Reed, Rolf K

2012-01-01

The tumor microenvironment is pivotal in tumor progression. Thus, we aimed to develop a mammary tumor model to elucidate molecular characteristics in the stroma versus the tumor cell compartment by global gene expression. Secondly, since tumor hypoxia influences several aspects of tumor pathophysiology, we hypothesized that hyperoxia might have an inhibitory effect on tumor growth per se. Finally, we aimed to identify differences in gene expression and key molecular mechanisms, both in the native state and following treatment. 4T1 dsRed breast cancer cells were injected into eGFP expressing NOD/SCID mice. Group 1 was exposed to 3 intermittent HBO treatments (Day 1, 4 and 7), Group 2 to 7 daily HBO treatments (both 2.5bar, 100% O 2 , à 90 min), whereas the controls were exposed to a normal atmosphere. Tumor growth, histology, vascularisation, cell proliferation, cell death and metastasis were assessed. Fluorescence-activated cell sorting was used to separate tumor cells from stromal cells prior to gene expression analysis. The purity of sorted cells was verified by fluorescence microscopy. Gene expression profiling demonstrated that highly expressed genes in the untreated tumor stroma included constituents of the extracellular matrix and matrix metalloproteinases. Tumor growth was significantly inhibited by HBO, and the MAPK pathway was found to be significantly reduced. Immunohistochemistry indicated a significantly reduced microvessel density after intermittent HBO, whereas daily HBO did not show a similar effect. The anti-angiogenic response was reflected in the expression trends of angiogenic factors. The present in vivo mammary tumor model enabled us to separate tumor and stromal cells, and demonstrated that the two compartments are characterized by distinct gene expressions, both in the native state and following HBO treatments. Furthermore, hyperoxia induced a significant tumor growth-inhibitory effect, with significant down-regulation of the MAPK pathway

Denys-Drash syndrome associated WT1 glutamine 369 mutants have altered sequence-preferences and altered responses to epigenetic modifications

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Hashimoto, Hideharu; Zhang, Xing; Zheng, Yu; Wilson, Geoffrey G.; Cheng, Xiaodong

2016-09-04

Mutations in human zinc-finger transcription factor WT1 result in abnormal development of the kidneys and genitalia and an array of pediatric problems including nephropathy, blastoma, gonadal dysgenesis and genital discordance. Several overlapping phenotypes are associated with WT1 mutations, including Wilms tumors, Denys-Drash syndrome (DDS), Frasier syndrome (FS) and WAGR syndrome (Wilms tumor, aniridia, genitourinary malformations, and mental retardation). These conditions vary in severity from individual to individual; they can be fatal in early childhood, or relatively benign into adulthood. DDS mutations cluster predominantly in zinc fingers (ZF) 2 and 3 at the C-terminus of WT1, which together with ZF4 determine the sequence-specificity of DNA binding. We examined three DDS associated mutations in ZF2 of human WT1 where the normal glutamine at position 369 is replaced by arginine (Q369R), lysine (Q369K) or histidine (Q369H). These mutations alter the sequence-specificity of ZF2, we find, changing its affinity for certain bases and certain epigenetic forms of cytosine. X-ray crystallography of the DNA binding domains of normal WT1, Q369R and Q369H in complex with preferred sequences revealed the molecular interactions responsible for these affinity changes. DDS is inherited in an autosomal dominant fashion, implying a gain of function by mutant WT1 proteins. This gain, we speculate, might derive from the ability of the mutant proteins to sequester WT1 into unproductive oligomers, or to erroneously bind to variant target sequences.

ELFN1-AS1: A Novel Primate Gene with Possible MicroRNA Function Expressed Predominantly in Human Tumors

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Dmitrii E. Polev

2014-01-01

Full Text Available Human gene LOC100505644 uncharacterized LOC100505644 [Homo sapiens] (Entrez Gene ID 100505644 is abundantly expressed in tumors but weakly expressed in few normal tissues. Till now the function of this gene remains unknown. Here we identified the chromosomal borders of the transcribed region and the major splice form of the LOC100505644-specific transcript. We characterised the major regulatory motifs of the gene and its splice sites. Analysis of the secondary structure of the major transcript variant revealed a hairpin-like structure characteristic for precursor microRNAs. Comparative genomic analysis of the locus showed that it originated in primates de novo. Taken together, our data indicate that human gene LOC100505644 encodes some non-protein coding RNA, likely a microRNA. It was assigned a gene symbol ELFN1-AS1 (ELFN1 antisense RNA 1 (non-protein coding. This gene combines features of evolutionary novelty and predominant expression in tumors.

Expression of the BRCA1 gene in a breast tumor: Correlation with the effect of neoadjuvant chemotherapy

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Tsyganov, M. M.; Ibragimova, M. K.; Deryusheva, I. V.; Slonimskaya, E. M.; Litviakov, N. V.

2017-09-01

Most current research is limited by only germinal mutations of the BRCA1 gene (more often 5382insC) and the number of studies, which characterize various somatic alterations of the BRCA1 gene in a tumor, namely the expression of this gene and its correlation with the efficiency of chemotherapy, which is scarce. Taking into account the data on the connection between the genetic mutation of BRCA1 with the high efficiency of the platinum medication one may suggest that the expression of the BRCA1 gene is also associated with the high sensitivity of the tumor to the platinum medication. Aim: to evaluate the correlation between the expression of the BRCA1 gene in a breast tumor with the neoadjuvant chemotherapy (NACT) efficiency. The research included 86 patients with BC. We evaluated the expression of BRCA1 in the tumor material before and after NACT. We established that objective response to NACT is connected with a high level of BRCA1 in the general group of patients (p = 0.01) and in case of docetaxel monotherapy (p < 0.05).

Galectin-3 disruption impaired tumoral angiogenesis by reducing VEGF secretion from TGFβ1-induced macrophages

International Nuclear Information System (INIS)

Machado, Camila Maria Longo; Andrade, Luciana Nogueira Sousa; Teixeira, Verônica Rodrigues; Costa, Fabrício Falconi; Melo, Camila Morais; Santos, Sofia Nascimento dos; Nonogaki, Suely; Liu, Fu-Tong; Bernardes, Emerson Soares; Camargo, Anamaria Aranha; Chammas, Roger

2014-01-01

In order to study the role of galectin-3 in tumor angiogenesis associated with tumor-associated macrophages (TAM) and tumor parenchyma, the galectin-3 expression was reconstituted in Tm1 melanoma cell line that lacks this protein. Galectin-3-expressing cells (Tm1G3) and mock-vector transfected cells (Tm1N3) were injected into wild-type (WT) and galectin-3 knockout (KO) C57Bl/6 mice. Tumors originated from Tm1G3 were larger in tumor volume with enlarged functional vessels, decreased necrotic areas, and increased vascular endothelial growth factor (VEGF) protein levels. Galectin-3-nonexpressing-cells injected into WT and KO showed increased levels of transforming growth factor beta 1 (TGFβ1) and, in WT animals this feature was also accompanied by increased VEGFR2 expression and its phosphorylation. In KO animals, tumors derived from galectin-3-expressing cells were infiltrated by CD68 + -cells, whereas in tumors derived from galectin-3-nonexpressing-cells, CD68 + cells failed to infiltrate tumors and accumulated in the periphery of the tumor mass. In vitro studies showed that Tm1G3 secreted more VEGF than Tm1N3 cells. In the latter case, TGFβ1 induced VEGF production. Basal secretion of VEGF was higher in WT-bone marrow-derived macrophages (BMDM) than in KO-BMDM. TGFβ1 induced secretion of VEGF only in WT-BMDM. Tm1G3-induced tumors had the Arginase I mRNA increased, which upregulated alternative macrophage (M2)/TAM induction. M2 stimuli, such as interleukin-4 (IL4) and TGFβ1, increased Arginase I protein levels and galectin-3 expression in WT- BMDM, but not in cells from KO mice. Hence, we report that galectin-3 disruption in tumor stroma and parenchyma decreases angiogenesis through interfering with the responses of macrophages to the interdependent VEGF and TGFβ1 signaling pathways

Clonal expansion to anaplasia in Wilms` tumors is associated with p53 mutations

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Pelletier, J.; Beckwith, B.; Bardeesy, N. [Loma Linda Univ., CA (United States)]|[McGill Univ., Montreal (Canada)

1994-09-01

The genetics of Wilms` tumor (WT), a pediatric malignancy of the kidney, is complex. Three loci are implicated in WT initiation and include the WT1 tumor suppressor gene (residing at 11p13), an 11p15 locus, and a non-11p locus. As well, allelic loss at 16q24 in {approximately}20% of sporadic WTs suggests the location of (an) additional gene(s) involved in tumor progression. Initiation and progression in WTs is associated with multiple histological variants. Anaplasia is a rare WT subtype associated with poor prognosis and defined by enlarged and multipolar mitotic figures, a threefold nuclear enlargement (compared with adjacent nuclei of the same cell type), and hyperchromasia of the enlarged nuclei. We have previously demonstrated that p53 gene mutations are exclusively associated with anaplastic WTs, being absent from a large number of non-anaplastic WTs analyzed. To determine if such mutations are involved in clonal progression to anaplasia, we performed a retrospective analysis of histologically defined sections from tumor specimens. Six of ten WTs demonstrated p53 mutations by PCR-single stranded conformational polymorphism analysis. Two of these samples were paired, consisting of geographically demarcated anaplastic cells embedded within a non-anaplastic tumor bed. In these cases, p53 mutations were only present in the anaplastic region of the tumor. An overall decrease in the number of apoptotic cells was found associated with the anaplastic tumor region, compared to adjacent non-anaplastic tumor bed. These results indicate that p53 mutations arise during progression to anaplasia late in Wilms` tumor etiology and are associated with a more aggressive form of this cancer.

Constitutional and somatic methylation status of DMRH19 and KvDMR in Wilms tumor patients

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Leila C.A. Cardoso

2012-01-01

Full Text Available The most frequent epigenetic alterations in Wilms tumor (WT occur at WT2, assigned to 11p15. WT2 consists of two domains: telomeric domain 1 (DMRH19 that contains the IGF2 gene and an imprinted maternally expressed transcript (H19 and centromeric domain 2 (KvDMR that contains the genes KCNQ1, KCNQ1OT1 and CDKN1C. In this work, we used pyrosequencing and MS-MLPA to compare the methylation patterns of DMRH19/KvDMR in blood and tumor samples from 40 WT patients. Normal constitutional KvDMR methylation indicated that most of the epigenetic alterations in WT occur at DMRH19. Constitutional DMRH19 hypermethylation (HM DMRH19 was observed in two patients with Beckwith-Wiedemann syndrome. Pyrosequencing and MS-MLPA showed HM DMRH19 in 28/34 tumor samples: 16/34 with isolated HM DMRH19 and 12/34 with concomitant HM DMRH19 and KvDMR hypomethylation, indicating paternal uniparental disomy. With the exception of one blood sample, the MS-MLPA and pyrosequencing findings were concordant. Diffuse or focal anaplasia was present in five tumor samples and was associated with isolated somatic HM DMRH19 in four of them. Constitutional 11p15 methylation abnormalities were present in 5% of the samples and somatic abnormalities in the majority of tumors. Combined analysis of DMRH19/KvDMR by pyrosequencing and MS-MLPA is beneficial for characterizing epigenetic anomalies in WT, and MS-MLPA is useful and reliable for estimation of DNA methylation in a clinical setting.

WT1 Is Necessary for the Proliferation and Migration of Cells of Renin Lineage Following Kidney Podocyte Depletion

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Natalya V. Kaverina

2017-10-01

Full Text Available Wilms' tumor suppressor 1 (WT1 plays an important role in cell proliferation and mesenchymal-epithelial balance in normal development and disease. Here, we show that following podocyte depletion in three experimental models, and in patients with focal segmental glomerulosclerosis (FSGS and membranous nephropathy, WT1 increased significantly in cells of renin lineage (CoRL. In an animal model of FSGS in RenWt1fl/fl reporter mice with inducible deletion of WT1 in CoRL, CoRL proliferation and migration to the glomerulus was reduced, and glomerular disease was worse compared with wild-type mice. To become podocytes, CoRL undergo mesenchymal-to-epithelial transformation (MET, typified by reduced staining for mesenchymal markers (MYH11, SM22, αSMA and de novo expression of epithelial markers (E-cadherin and cytokeratin18. Evidence for changes in MET markers was barely detected in RenWt1fl/fl mice. Our results show that following podocyte depletion, WT1 plays essential roles in CoRL proliferation and migration toward an adult podocyte fate.

Molecular characterization of the porcine deleted in malignant brain tumors 1 gene (DMBT1)

DEFF Research Database (Denmark)

Haase, Bianca; Humphray, Sean J; Lyer, Stefan

2006-01-01

The human gene deleted in malignant brain tumors 1 (DMBT1) is considered to play a role in tumorigenesis and pathogen defense. It encodes a protein with multiple scavenger receptor cysteine-rich (SRCR) domains, which are involved in recognition and binding of a broad spectrum of bacterial pathogens...

The molecular mechanism of gene-radiotherapy of tumor

International Nuclear Information System (INIS)

Zhu Xian

2004-01-01

Gene-radiotherapy of tumor is a new method which is induced by ionizing radiation. The molecular mechanism is to activate various molecular target by many ways and induce the apoptosis of tumor cell. It is a gene therapy based on the radiation-inducible property of the Egr-1 gene. It has good application prospect in therapy of tumor

[Methylation of selected tumor-supressor genes in benign and malignant ovarian tumors].

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Cul'bová, M; Lasabová, Z; Stanclová, A; Tilandyová, P; Zúbor, P; Fiolka, R; Danko, J; Visnovský, J

2011-09-01

To evaluate the usefullness of examination of methylation status of selected tumor-supressor genes in early diagnosis of ovarian cancer. Prospective clinical study. Department of Gynecology and Obstetrics, Department of Molecular Biology, Jessenius Medical Faculty, Commenius University, Martin, Slovak Republic. In this study we analyzed hypermethylation of 5 genes RASSF1A, GSTP, E-cadherin, p16 and APC in ovarian tumor samples from 34 patients - 13 patients with epithelial ovarian cancer, 2 patients with border-line ovarian tumors, 12 patients with benign lesions of ovaries and 7 patients with healthy ovarian tissue. The methylation status of promoter region of tumor-supressor genes was determined by Methylation Specific Polymerase Chain Reaction (MSP) using a nested two-step approach with bisulfite modified DNA template and specific primers. Gene methylation analysis revealed hypermethylation of gene RASSF1A (46%) and GSTP (8%) only in malignant ovarian tissue samples. Ecad, p16 and APC genes were methylated both in maignant and benign tissue samples. Methylation positivity in observed genes was present independently to all clinical stages of ovarian cancer and to tumor grades. However, there was observed a trend of increased number and selective involvement of methylated genes with increasing disease stages. Furthermore, there was no association between positive methylation status and histological subtypes of ovarian carcinomas. RASSF1A and GSTP promoter methylation positivity is associated with ovarian cancer. The revealed gene-selective methylation positivity and the increased number of methylated genes with advancing disease stages could be considered as a useful molecular marker for early detection of ovarian cancer. However, there is need to find diagnostic approach of specifically and frequently methylated genes to determining a methylation phenotype for early detection of ovarian malignancies.

NUTM1 Gene Fusions Characterize a Subset of Undifferentiated Soft Tissue and Visceral Tumors.

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Dickson, Brendan C; Sung, Yun-Shao; Rosenblum, Marc K; Reuter, Victor E; Harb, Mohammed; Wunder, Jay S; Swanson, David; Antonescu, Cristina R

2018-05-01

NUT midline carcinoma is an aggressive tumor that occurs mainly in the head and neck and, less frequently, the mediastinum and lung. Following identification of an index case of a NUTM1 fusion positive undifferentiated soft tissue tumor, we interrogated additional cases of primary undifferentiated soft tissue and visceral tumors for NUTM1 abnormalities. Targeted next-generation sequencing was performed on RNA extracted from formalin-fixed paraffin-embedded tissue, and results validated by fluorescence in situ hybridization using custom bacterial artificial chromosome probes. Six patients were identified: mean age of 42 years (range, 3 to 71 y); equal sex distribution; and, tumors involved the extremity soft tissues (N=2), kidney (N=2), stomach, and brain. On systemic work-up at presentation all patients lacked a distant primary tumor. Morphologically, the tumors were heterogenous, with undifferentiated round-epithelioid-rhabdoid cells arranged in solid sheets, nests, and cords. Mitotic activity was generally brisk. Four cases expressed pancytokeratin, but in only 2 cases was this diffuse. Next-generation sequencing demonstrated the following fusions: BRD4-NUTM1 (3 cases), BRD3-NUTM1, MXD1-NUTM1, and BCORL1-NUTM1. Independent testing by fluorescence in situ hybridization confirmed the presence of NUTM1 and partner gene rearrangement. This study establishes that NUT-associated tumors transgress the midline and account for a subset of primitive neoplasms occurring in soft tissue and viscera. Tumors harboring NUTM1 gene fusions are presumably underrecognized, and the extent to which they account for undifferentiated mesenchymal, neuroendocrine, and/or epithelial neoplasms is unclear. Moreover, the relationship, if any, between NUT-associated tumors in soft tissue and/or viscera, and conventional NUT carcinoma, remains to be elucidated.

Acute WT1-positive promyelocytic leukemia with hypogranular variant morphology, bcr-3 isoform of PML-RARα and Flt3-ITD mutation: a rare case report

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Xi Zhang

Full Text Available ABSTRACT CONTEXT: Acute promyelocytic leukemia (APL accounts for 8% to 10% of cases of acute myeloid leukemia (AML. Remission in cases of high-risk APL is still difficult to achieve, and relapses occur readily. CASE REPORT: Here, we describe a case of APL with high white blood cell counts in blood tests and hypogranular variant morphology in bone marrow, together with fms-like tyrosine kinase-3 with internal tandem duplication mutations (FLT3-ITD, and bcr-3 isoform of PML-RARα. Most importantly, we detected high level of Wilms’ tumor gene (WT1 in marrow blasts, through the reverse transcription polymerase chain reaction (RT-PCR. To date, no clear conclusions about an association between WT1 expression levels and APL have been reached. This patient successively received a combined treatment regimen consisting of hydroxycarbamide, arsenic trioxide and idarubicin plus cytarabine, which ultimately enabled complete remission. Unfortunately, he subsequently died of sudden massive hemoptysis because of pulmonary infection. CONCLUSION: Based on our findings and a review of the literature, abnormal functioning of WT1 may be a high-risk factor in cases of APL. Further studies aimed towards evaluating the impact of WT1 expression on the prognosis for APL patients are of interest.

Down-regulation of HSP40 gene family following OCT4B1 suppression in human tumor cell lines

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Mohammad Reza Mirzaei

2016-02-01

Full Text Available Objective(s: The OCT4B1, as one of OCT4 variants, is expressed in cancer cell lines and tissues more than other variants and plays an important role in apoptosis and stress (heat shock protein pathways. The present study was designed to determine the effects of OCT4B1 silencing on expressional profile of HSP40 gene family expression in three different human tumor cell lines. Materials and Methods: The OCT4B1 expression was suppressed by specific siRNA transfection in AGS (gastric adenocarcinoma, 5637 (bladder tumor and U-87MG (brain tumor cell lines employing Lipofectamine reagent. Real-time PCR array technique was employed for RNA qualification. The fold changes were calculated using RT2 Profiler PCR array data analysis software version 3.5. Results: Our results indicated that fifteen genes (from 36 studied genes were down-regulated and two genes (DNAJC11 and DNAJC5B were up-regulated in all three studied tumor cell lines by approximately more than two folds. The result of other studied genes (19 genes showed different expressional pattern (up or down-expression based on tumor cell lines. Conclusion: According to the findings of the present study, we may suggest that there is a direct correlation between OCT4B1 expression in tumor cell lines (and tissues and HSP40 family gene expressions to escape from apoptosis and cancer expansion.

Mechanic effect of pulsed focused ultrasound in tumor and muscle tissue evaluated by MRI, histology, and microarray analysis

International Nuclear Information System (INIS)

Hundt, Walter; Yuh, Esther L.; Steinbach, Silke; Bednarski, Mark D.; Guccione, Samira

2010-01-01

The purpose of this study was to investigate the effect of pulsed high-intensity focused ultrasound (HIFU) to tumor and muscle tissue. Pulsed HIFU was applied to tumor and muscle tissue in C3H/Km mice. Three hours after HIFU treatment pre- and post-contrast T1-wt, T2-wt images and a diffusion-wt STEAM-sequence were obtained. After MR imaging, the animals were euthenized and the treated tumor and muscle was taken out for histology and functional genomic analysis. In the tumor tissue a slight increase of the diffusion coefficient could be found. In the muscle tissue T2 images showed increased signal intensity and post-contrast T1 showed a decreased contrast uptake in the center and a severe contrast uptake in the surrounding muscle tissue. A significant increase of the diffusion coefficient was found. Gene expression analysis revealed profound changes in the expression levels of 29 genes being up-regulated and 3 genes being down-regulated in the muscle tissue and 31 genes being up-regulated and 15 genes being down-regulated in the SCCVII tumor tissue. Seven genes were up-regulated in both tissue types. The highest up-regulated gene in the tumor and muscle tissue encoded for Mouse histone H2A.1 gene (FC = 13.2 ± 20.6) and Apolipoprotein E (FC = 12.8 ± 27.4) respectively MHC class III (FC = 83.7 ± 67.4) and hsp70 (FC = 75.3 ± 85.0). Immunoblot confirmed the presence of HSP70 protein in the muscle tissue. Pulsed HIFU treatment on tumor and muscle tissue results in dramatic changes in gene expression, indicating that the effect of pulsed HIFU is in some regard dependent and also independent of the tissue type.

Characterization of TEM1/endosialin in human and murine brain tumors

International Nuclear Information System (INIS)

Carson-Walter, Eleanor B; Walter, Kevin A; Winans, Bethany N; Whiteman, Melissa C; Liu, Yang; Jarvela, Sally; Haapasalo, Hannu; Tyler, Betty M; Huso, David L; Johnson, Mahlon D

2009-01-01

TEM1/endosialin is an emerging microvascular marker of tumor angiogenesis. We characterized the expression pattern of TEM1/endosialin in astrocytic and metastatic brain tumors and investigated its role as a therapeutic target in human endothelial cells and mouse xenograft models. In situ hybridization (ISH), immunohistochemistry (IH) and immunofluorescence (IF) were used to localize TEM1/endosialin expression in grade II-IV astrocytomas and metastatic brain tumors on tissue microarrays. Changes in TEM1/endosialin expression in response to pro-angiogenic conditions were assessed in human endothelial cells grown in vitro. Intracranial U87MG glioblastoma (GBM) xenografts were analyzed in nude TEM1/endosialin knockout (KO) and wildtype (WT) mice. TEM1/endosialin was upregulated in primary and metastatic human brain tumors, where it localized primarily to the tumor vasculature and a subset of tumor stromal cells. Analysis of 275 arrayed grade II-IV astrocytomas demonstrated TEM1/endosialin expression in 79% of tumors. Robust TEM1/endosialin expression occurred in 31% of glioblastomas (grade IV astroctyomas). TEM1/endosialin expression was inversely correlated with patient age. TEM1/endosialin showed limited co-localization with CD31, αSMA and fibronectin in clinical specimens. In vitro, TEM1/endosialin was upregulated in human endothelial cells cultured in matrigel. Vascular Tem1/endosialin was induced in intracranial U87MG GBM xenografts grown in mice. Tem1/endosialin KO vs WT mice demonstrated equivalent survival and tumor growth when implanted with intracranial GBM xenografts, although Tem1/endosialin KO tumors were significantly more vascular than the WT counterparts. TEM1/endosialin was induced in the vasculature of high-grade brain tumors where its expression was inversely correlated with patient age. Although lack of TEM1/endosialin did not suppress growth of intracranial GBM xenografts, it did increase tumor vascularity. The cellular localization of TEM1

G-protein inwardly rectifying potassium channel 1 (GIRK 1) gene expression correlates with tumor progression in non-small cell lung cancer

International Nuclear Information System (INIS)

Takanami, Iwao; Inoue, Yoshimasa; Gika, Masatoshi

2004-01-01

G-protein inwardly rectifying potassium channel 1 (GIRK1) is thought to play a role in cell proliferation in cancer, and GIRK1 gene expression level may define a more aggressive phenotype. We detected GIRK1 expression in tissue specimens from patients with non-small cell lung cancers (NSCLCs) and assessed their clinical characteristics. Using reverse transcription-polymerase chain reaction (RT-PCR) analyses, we quantified the expression of GIRK1 in 72 patients with NSCLCs to investigate the relationship between GIRK1 expression and clinicopathologic factors and prognosis. In 72 NSCLC patients, 50 (69%) samples were evaluated as having high GIRK1 gene expression, and 22 (31%) were evaluated as having low GIRK1 gene expression. GIRK1 gene expression was significantly associated with lymph node metastasis, stage (p = 0.0194 for lymph node metastasis; p = 0.0207 for stage). The overall and stage I survival rates for patients with high GIRK1 gene expressed tumors was significantly worse than for those individuals whose tumors had low GIRK1 expression (p = 0.0004 for the overall group; p = 0.0376 for stage I). These data indicate that GIRK1 may contribute to tumor progression and GIRK1 gene expression can serve as a useful prognostic marker in the overall and stage I NSCLCs

Gene Expression of Glucose Transporter 1 (GLUT1), Hexokinase 1 and Hexokinase 2 in Gastroenteropancreatic Neuroendocrine Tumors

DEFF Research Database (Denmark)

Binderup, Tina; Knigge, Ulrich; Federspiel, Birgitte Hartnack

2013-01-01

-associated genes and to compare this with FDG-PET imaging as well as with the cellular proliferation index in two cancer entities with different malignant potential. Using real-time PCR, gene expression of GLUT1, HK1 and HK2 were studied in 34 neuroendocrine tumors (NETs) in comparison with 14 colorectal...... adenocarcinomas (CRAs). The Ki67 proliferation index and, when available, FDG-PET imaging was compared with gene expression. Overexpression of GLUT1 gene expression was less frequent in NETs (38%) compared to CRAs (86%), P = 0.004. HK1 was overexpressed in 41% and 71% of NETs and CRAs, respectively (P = 0.......111) and HK2 was overexpressed in 50% and 64% of NETs and CRAs, respectively (P = 0.53). There was a significant correlation between the Ki67 proliferation index and GLUT1 gene expression for the NETs (R = 0.34, P = 0.047), but no correlation with the hexokinases. FDG-PET identified foci in significantly...

The Use of cDNA Microarray to Study Gene Expression in Wnt-1 Induced Mammary Tumors

National Research Council Canada - National Science Library

Huang, Shixia

2002-01-01

.... Specifically, we have collected tissue samples from virgin mammary glands, hyperplastic mammary glands, Wnt- 1 mammary tumors, and tumors metastasized to the lung, and compared their gene expression patterns...

Intra-Tumor Genetic Heterogeneity in Wilms Tumor: Clonal Evolution and Clinical Implications

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George D. Cresswell

2016-07-01

Full Text Available The evolution of pediatric solid tumors is poorly understood. There is conflicting evidence of intra-tumor genetic homogeneity vs. heterogeneity (ITGH in a small number of studies in pediatric solid tumors. A number of copy number aberrations (CNA are proposed as prognostic biomarkers to stratify patients, for example 1q+ in Wilms tumor (WT; current clinical trials use only one sample per tumor to profile this genetic biomarker. We multisampled 20 WT cases and assessed genome-wide allele-specific CNA and loss of heterozygosity, and inferred tumor evolution, using Illumina CytoSNP12v2.1 arrays, a custom analysis pipeline, and the MEDICC algorithm. We found remarkable diversity of ITGH and evolutionary trajectories in WT. 1q+ is heterogeneous in the majority of tumors with this change, with variable evolutionary timing. We estimate that at least three samples per tumor are needed to detect >95% of cases with 1q+. In contrast, somatic 11p15 LOH is uniformly an early event in WT development. We find evidence of two separate tumor origins in unilateral disease with divergent histology, and in bilateral WT. We also show subclonal changes related to differential response to chemotherapy. Rational trial design to include biomarkers in risk stratification requires tumor multisampling and reliable delineation of ITGH and tumor evolution.

Tumor-extrinsic discoidin domain receptor 1 promotes mammary tumor growth by regulating adipose stromal interleukin 6 production in mice.

Science.gov (United States)

Sun, Xiujie; Gupta, Kshama; Wu, Bogang; Zhang, Deyi; Yuan, Bin; Zhang, Xiaowen; Chiang, Huai-Chin; Zhang, Chi; Curiel, Tyler J; Bendeck, Michelle P; Hursting, Stephen; Hu, Yanfen; Li, Rong

2018-02-23

Discoidin domain receptor 1 (DDR1) is a collagen receptor that mediates cell communication with the extracellular matrix (ECM). Aberrant expression and activity of DDR1 in tumor cells are known to promote tumor growth. Although elevated DDR1 levels in the stroma of breast tumors are associated with poor patient outcome, a causal role for tumor-extrinsic DDR1 in cancer promotion remains unclear. Here we report that murine mammary tumor cells transplanted to syngeneic recipient mice in which Ddr1 has been knocked out (KO) grow less robustly than in WT mice. We also found that the tumor-associated stroma in Ddr1- KO mice exhibits reduced collagen deposition compared with the WT controls, supporting a role for stromal DDR1 in ECM remodeling of the tumor microenvironment. Furthermore, the stromal-vascular fraction (SVF) of Ddr1 knockout adipose tissue, which contains committed adipose stem/progenitor cells and preadipocytes, was impaired in its ability to stimulate tumor cell migration and invasion. Cytokine array-based screening identified interleukin 6 (IL-6) as a cytokine secreted by the SVF in a DDR1-dependent manner. SVF-produced IL-6 is important for SVF-stimulated tumor cell invasion in vitro , and, using antibody-based neutralization, we show that tumor promotion by IL-6 in vivo requires DDR1. In conclusion, our work demonstrates a previously unrecognized function of DDR1 in promoting tumor growth. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Real-time PCR analysis of genes encoding tumor antigens in esophageal tumors and a cancer vaccine

DEFF Research Database (Denmark)

Weinert, Brian T; Krishnadath, Kausilia K; Milano, Francesca

2009-01-01

Tumor antigens are the primary target of therapeutic cancer vaccines. We set out to define and compare the expression pattern of tumor antigen genes in esophagus carcinoma biopsies and in an allogeneic tumor lysate-based cancer vaccine, MelCancerVac. Cells used for vaccine production were treated...... in the production of the vaccine. Quantitative PCR was used to assay 74 tumor antigen genes in patients with squamous cell carcinoma of the esophagus. 81% (13/16) of tumors expressed more than five cancer/testis (CT) antigens. A total of 96 genes were assayed in the tumor cell clone (DDM1.7) used to make tumor cell...

Quantitative analysis of MDR1 (multidrug resistance) gene expression in human tumors by polymerase chain reaction

International Nuclear Information System (INIS)

Noonan, K.E.; Beck, C.; Holzmayer, T.A.; Chin, J.E.; Roninson, I.B.; Wunder, J.S.; Andrulis, I.L.; Gazdar, A.F.; Willman, C.L.; Griffith, B.; Von Hoff, D.D.

1990-01-01

The resistance of tumor cells ot chemotheraprutic drugs is a major obstacle to successful cancer chemotherapy. In human cells, expression of the MDR1 gene, encoding a transmembrane efflux pump (P-glycoprotein), leads to decreased intracellular accumulation and resistance to a variety of lipophilic drugs (multidrug resistance; MDR). The levels of MDR in cell lines selected in bitro have been shown to correlate with the steady-state levels of MDR1 mRNA and P-glycoprotein. In cells with a severalfold increase in cellular drug resistance, MDR1 expression levels are close to the limits of detection by conventional assays. MDR1 expression has been frequently observed in human tumors after chemotherapy and in some but not all types of clinically refactory tumors untreated with chemotherapeutic drugs. The authors have devised a highly sensitive, specific, and quantitative protocol for measuring the levels of MDR1 mRNA in clincal samples, based on the polymerase chain reaction. They have used this assay to measure MDR1 gene expression in MDR cell lines and >300 normal tissues, tumor-derived cell lines, and clinical specimens of untreated tumors of the types in which MDR1 expression was rarely observed by standard assays. Low levels of MDR1 expression were found by polymerase chain reaction in most solid tumors and leukemias tested. The frequency of samples without detectable MDR1 expression varied among different types of tumors; MDR1-negative samples were ost common among tumor types known to be relatively responsive to chemotherapy

Centrosome clustering and cyclin D1 gene amplification in double minutes are common events in chromosomal unstable bladder tumors

International Nuclear Information System (INIS)

Rey, Javier del; Prat, Esther; Ponsa, Immaculada; Lloreta, Josep; Gelabert, Antoni; Algaba, Ferran; Camps, Jordi; Miró, Rosa

2010-01-01

Aneuploidy, centrosome abnormalities and gene amplification are hallmarks of chromosome instability (CIN) in cancer. Yet there are no studies of the in vivo behavior of these phenomena within the same bladder tumor. Twenty-one paraffin-embedded bladder tumors were analyzed by conventional comparative genome hybridization and fluorescence in situ hybridization (FISH) with a cyclin D1 gene (CCND1)/centromere 11 dual-color probe. Immunofluorescent staining of α, β and γ tubulin was also performed. Based on the CIN index, defined as the percentage of cells not displaying the modal number for chromosome 11, tumors were classified as CIN-negative and CIN-positive. Fourteen out of 21 tumors were considered CIN-positive. All T1G3 tumors were included in the CIN-positive group whereas the majority of Ta samples were classified as CIN-negative tumors. Centrosome clustering was observed in six out of 12 CIN-positive tumors analyzed. CCND1 amplification in homogeneously staining regions was present in six out of 14 CIN-positive tumors; three of them also showed amplification of this gene in double minutes. Complex in vivo behavior of CCND1 amplicon in bladder tumor cells has been demonstrated by accurate FISH analysis on paraffin-embedded tumors. Positive correlation between high heterogeneity, centrosome abnormalities and CCND1 amplification was found in T1G3 bladder carcinomas. This is the first study to provide insights into the coexistence of CCND1 amplification in homogeneously staining regions and double minutes in primary bladder tumors. It is noteworthy that those patients whose tumors showed double minutes had a significantly shorter overall survival rate (p < 0.001)

Coamplification in tumors of KRAS2, type 2 inositol 1,4,5 triphosphate receptor gene, and a novel human gene, KRAG

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Heighway, J.; Betticher, D.C.; Altermatt, H.J. [Univ. Hospital of Berne (Switzerland)] [and others

1996-07-01

Analysis of a region of DNA, coamplified in tumors with KRAS2, resulted in the identification of the human homologue of the mouse KRAG gene. The gene was widely expressed in range of cell lines, tumors, and normal tissue and demonstrated a high degree of alternate splicing. A human KRAG cDNA sequence, with a structure similar to that encoded by the amplified gene in mouse Y1 adrenal carcinoma cells, was isolated by RT-PCR. The predicted amino acid similarity between the two sequences was 91%, and hydrophobicity plots suggested a structure closely resembling that of transmembrane 4 superfamily members. Identification of a PCR-based restriction fragment length polymorphism allele-specific splicing differences in tumors. Northern analysis of mRNA derived from a range of tissues suggested high level expression in muscle and confirmed alternate splicing. To facilitate the analysis of exon junctions, a YAC clone encoding the genomic sequence was identified. This allowed the localization of KRAG to human chromosome 12p11.2. Isolation of one end of this nonchimeric clone demonstrated a perfect match with a 247-bp sequence within the 3{prime} untranslated region of the type 2 1,4,5-inositol triphosphate receptor gene. Multiplex PCR confirmed the inclusion of both genes. Multiplex PCR confirmed the inclusion of both genes in the KRAS2 amplicon in human malignancy, suggesting that either may contribute to the malignant phenotypes. 35 refs., 6 figs., 1 tab.

Effect of Pre-Aging Conditions on Bake-Hardening Response of Al-0.4 wt%Mg-1.2 wt%Si-0.1 wt%Mn Alloy Sheets

International Nuclear Information System (INIS)

Lee, Kwang-jin; Woo, Kee-do

2011-01-01

Pre-aging heat treatment after solution heat treatment (SHT) of Al-0.4 wt%Mg-1.2 wt%Si-0.1 wt%Mn alloy sheets for auto-bodies was carried out to investigate the effect of pre-aging and its conditions on the bake-hardening response. Mechanical properties were evaluated by a tensile and Vickers hardness test. Microstructural observation was also performed using a transmission electron microscope (TEM). It was revealed that pre-aging treatments play a great role in the bake-hardening response. In addition, it was found that the sphere-shaped nanosized clusters that can directly transit to the needle-shaped β” phase during the paint-bake process, not being dissolved into the matrix, are formed at 343 K. The result, reveals that the dominant factor of the bake-hardening response is the pre-aging temperature rather than the pre-aging time.

11p Microdeletion including WT1 but not PAX6, presenting with cataract, mental retardation, genital abnormalities and seizures: a case report

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Baekgaard Peter

2009-02-01

Full Text Available Abstract WAGR syndrome (Wilms' tumor, aniridia, genitourinary abnormalities and mental retardation and Potocki-Shaffer syndrome are rare contiguous gene deletion syndromes caused by deletions of the 11p14-p12 chromosome region. We present a patient with mental retardation, unilateral cataract, bilateral ptosis, genital abnormalities, seizures and a dysmorphic face. Cytogenetic analysis showed a deletion on 11p that was further characterized using FISH and MLPA analyses. The deletion (11p13-p12 located in the area between the deletions associated with the WAGR and Potocki-Shaffer syndromes had a maximum size of 8.5 Mb and encompasses 44 genes. Deletion of WT1 explains the genital abnormalities observed. As PAX6 was intact the cataract observed cannot be explained by a deletion of this gene. Seizures have been described in Potocki-Shaffer syndrome while mental retardation has been described in both WAGR and Potocki-Shaffer syndrome. Characterization of this patient contributes further to elucidate the function of the genes in the 11p14-p12 chromosome region.

WT1 isoform expression pattern in acute myeloid leukemia.

Science.gov (United States)

Luna, Irene; Such, Esperanza; Cervera, Jose; Barragán, Eva; Ibañez, Mariam; Gómez-Seguí, Inés; López-Pavía, María; Llop, Marta; Fuster, Oscar; Dolz, Sandra; Oltra, Silvestre; Alonso, Carmen; Vera, Belén; Lorenzo, Ignacio; Martínez-Cuadrón, David; Montesinos, Pau; Senent, M Leonor; Moscardó, Federico; Bolufer, Pascual; Sanz, Miguel A

2013-12-01

WT1 plays a dual role in leukemia development, probably due to an imbalance in the expression of the 4 main WT1 isoforms. We quantify their expression and evaluate them in a series of AML patients. Our data showed a predominant expression of isoform D in AML, although in a lower quantity than in normal CD34+ cells. We found a positive correlation between the total WT1 expression and A, B and C isoforms. The overexpression of WT1 in AML might be due to a relative increase in A, B and C isoforms, together with a relative decrease in isoform D expression. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effects of concomitant temozolomide and radiation therapies on WT1-specific T-cells in malignant glioma

International Nuclear Information System (INIS)

Chiba, Yasuyoshi; Hashimoto, Naoya; Tsuboi, Akihiro

2010-01-01

Immunotherapy targeting the Wilms' tumour 1 gene product has been proven safe and effective for treating malignant glioma in a phase II clinical study. Currently, radiation/temozolomide therapy is the standard treatment with only modest benefit. Whether combining radiation/temozolomide therapy with WT1 immunotherapy will have a negating effect on immunotherapy is still controversial because of the significant lymphocytopaenia induced by the former therapy. To address this issue, we investigated the changes in frequency and number of WT1-specific T-cells in patients with malignant gliomas. Twenty-two patients with newly diagnosed malignant glioma who received standard radiation/temozolomide therapy were recruited for the study. Blood samples were collected before treatment and on the sixth week of therapy. The frequencies and numbers of lymphocytes, CD8 + T-cells, WT1-specific T-cells, regulatory T-cells, natural killer cells and natural killer T-cells were measured and analysed using T-tests. Analysis of the frequency of T lymphocytes and its subpopulation showed an increase in regulatory T-cells, but no significant change was noted in the populations of T-cells, WT1-specific T-cells, natural killer (NK) cells and natural killer T (NKT) cells. Reductions in the total numbers of T-cells, WT1-specific T-cells, NK cells and NKT cells were mainly a consequence of the decrease in the total lymphocyte count. Radiation/temozolomide therapy did not significantly affect the frequency of WT1-specific T-cells, suggesting that the combination with WT1 immunotherapy may be possible, although further assessment in the clinical setting is warranted. (author)

OFFICIAL MEDICATIONS FOR ANTI-TUMOR GENE THERAPY

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E. R. Nemtsova

2016-01-01

Full Text Available This is a review of modern literature data of official medications for anti-tumor gene therapy as well as of medications that finished clinical trials.The article discusses the concept of gene therapy, the statistical analysis results of initiated clinical trials of gene products, the most actively developing directions of anticancer gene therapy, and the characteristics of anti-tumor gene medications.Various delivery systems for gene material are being examined, including viruses that are defective in  replication (Gendicine™ and Advexin and oncolytic (tumor specific conditionally replicating viruses (Oncorine™, ONYX-015, Imlygic®.By now three preparations for intra-tumor injection have been introduced into oncology clinical practice: two of them – Gendicine™ and Oncorine™ have been registered in China, and one of them – Imlygic® has been registered in the USA. Gendicine™ and Oncorine™ are based on the wild type p53 gene and are designed for treatment of patients with head and neck malignancies. Replicating adenovirus is the delivery system in Gendicine™, whereas oncolytic adenovirus is the vector for gene material in Oncorine™. Imlygic® is based on the  recombinant replicating HSV1 virus with an introduced GM–CSF gene and is designed for treatment of  melanoma patients. These medications are well tolerated and do not cause any serious adverse events. Gendicine™ and Oncorine™ are not effective in monotherapy but demonstrate pronounced synergism with chemoand radiation therapy. Imlygic® has just started the post marketing trials.

Expression of the p16{sup INK4a} tumor suppressor gene in rodent lung tumors

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Swafford, D.S.; Tesfaigzi, J.; Belinsky, S.A.

1995-12-01

Aberrations on the short arm of chromosome 9 are among the earliest genetic changes in human cancer. p16{sup INK4a} is a candidate tumor suppressor gene that lies within human 9p21, a chromosome region associated with frequent loss of heterozygosity in human lung tumors. The p16{sup INK4a} protein functions as an inhibitor of cyclin D{sub 1}-dependent kinases that phosphorylate the retinoblastoma (Rb) tumor suppressor gene product enabling cell-cycle progression. Thus, overexpression of cyclin D{sub 1}, mutation of cyclin-dependent kinase genes, or loss of p16{sup INK4a} function, can all result in functional inactivation of Rb. Inactivation of Rb by mutation or deletion can result in an increase in p16{sup INK4a} transcription, suggesting that an increased p16{sup INK4a} expression in a tumor cell signals dysfunction of the pathway. The p16{sup (INK4a)} gene, unlike some tumor suppressor genes, is rarely inactivated by mutation. Instead, the expression of this gene is suppressed in some human cancers by hypermethylation of the CpG island within the first exon or by homozygous deletion: 686. Chromosome losses have been observed at 9p21 syntenic loci in tumors of the mouse and rat, two species often used as animal models for pulmonary carcinogenesis. Expression of p16{sup INK4a} is lost in some mouse tumor cell lines, often due to homozygous deletion. These observations indicate that p16{sup INK4a} dysfunction may play a role in the development of neoplasia in rodents as well as humans. The purpose of the current investigation was to define the extent to which p16{sup INK4a} dysfunction contributes to the development of rodent lung tumors and to determine the mechanism of inactivation of the gene. There is no evidence to suggest a loss of function of the p16{sup INK4a} tumor suppressor gene in these primary murine lung tumors by mutation, deletion, or methylation.

Kras gene mutation and RASSF1A, FHIT and MGMT gene promoter hypermethylation: indicators of tumor staging and metastasis in adenocarcinomatous sporadic colorectal cancer in Indian population.

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Rupal Sinha

Full Text Available Colorectal cancer (CRC development involves underlying modifications at genetic/epigenetic level. This study evaluated the role of Kras gene mutation and RASSF1A, FHIT and MGMT gene promoter hypermethylation together/independently in sporadic CRC in Indian population and correlation with clinicopathological variables of the disease.One hundred and twenty four consecutive surgically resected tissues (62 tumor and equal number of normal adjacent controls of primary sporadic CRC were included and patient details including demographic characteristics, lifestyle/food or drinking habits, clinical and histopathological profiles were recorded. Polymerase chain reaction - Restriction fragment length polymorphism and direct sequencing for Kras gene mutation and Methylation Specific-PCR for RASSF1A, FHIT and MGMT genes was performed.Kras gene mutation at codon 12 & 13 and methylated RASSF1A, FHIT and MGMT gene was observed in 47%, 19%, 47%, 37% and 47% cases, respectively. Alcohol intake and smoking were significantly associated with presence of Kras mutation (codon 12 and MGMT methylation (p-value <0.049. Tumor stage and metastasis correlated with presence of mutant Kras codon 12 (p-values 0.018, 0.044 and methylated RASSF1A (p-values 0.034, 0.044, FHIT (p-values 0.001, 0.047 and MGMT (p-values 0.018, 0.044 genes. Combinatorial effect of gene mutation/methylation was also observed (p-value <0.025. Overall, tumor stage 3, moderately differentiated tumors, presence of lymphatic invasion and absence of metastasis was more frequently observed in tumors with mutated Kras and/or methylated RASSF1A, FHIT and MGMT genes.Synergistic interrelationship between these genes in sporadic CRC may be used as diagnostic/prognostic markers in assessing the overall pathological status of CRC.

Hsf-1 affects podocyte markers NPHS1, NPHS2 and WT1 in a transgenic mouse model of TTRVal30Met-related amyloidosis.

Science.gov (United States)

Petrakis, Ioannis; Mavroeidi, Vasiliki; Stylianou, Kostas; Andronikidi, Eva; Lioudaki, Eirini; Perakis, Kostas; Stratigis, Spyridon; Vardaki, Eleftheria; Zafeiri, Maria; Giannakakis, Kostantinos; Plaitakis, Andreas; Amoiridis, George; Saraiva, Maria Joao; Daphnis, Eugene

2013-09-01

Familial amyloid polyneuropathy is characterized by transthyretin (TTR) deposition in various tissues, including the kidneys. While deposition induces organ dysfunction, renal involvement in TTR-related amyloidosis could manifest from proteinuria to end-stage kidney failure. As proteinuria is considered result of glomerular filtration barrier injury we investigated whether TTR deposition affects either glomerular basement membrane (GBM) or podocytes. Immunohistochemistry, immunoblot and gene expression studies for nephrin, podocin and WT1 were run on renal tissue from human-TTRV30M transgenic mice hemizygous or homozygous for heat shock factor one (Hsf-1). Transmission electron microscopy was used for evaluation of podocyte foot process width (PFW) and GBM thickness in Hsf-1 hemizygous mice with or without TTRV30M or amyloid deposition. Glomeruli of hsf-1 hemizygous transgenic mice showed lower nephrin and podocin protein levels but an increased podocyte number when compared to Hsf-1 homozygous transgenic mice. Nephrin, podocin and WT1 gene expression levels were unaffected by the Hsf-1 carrier status. TTRV30M deposition was associated with increased PFW and GBM thickness. Under the effect of Hsf-1 hemizygosity, TTRV30M deposition has deleterious effects on GBM thickness, PFW and slit diaphragm composition, without affecting nephrin and podocin gene expression.

A t (11; 22 (p13; q12 EWS-WT 1 positive desmoplastic small round cell tumor of the maxilla: An unusual case indicating the role of molecular diagnosis in round cell sarcomas

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Rekhi B

2010-01-01

Full Text Available A desmoplastic small round cell tumor (DSRCT is an uncommon tumor characterized by polyphenotypic expression and a specific reciprocal translocation t (11; 22 (p13; q12. It has been rarely identified in the head and neck region. Herein, we describe a DSRCT in the maxilla of a young man, who was initially diagnosed with a primitive neuroectodermal tumor (PNET, based on histopathological appearance of a round cell tumor, with MIC2 and -FLI-1 positivity, on immunohistochemistry (IHC. Diagnosis of a DSRCT was confirmed on molecular analysis with positive -RT-PCR and sequencing results for EWS-WT1 transcript and negativity for EWS-FL1. The case is presented to highlight the value of molecular diagnosis in round cell sarcomas at uncommon sites, especially when similar IHC markers can be expressed in a PNET and a DSRCT. An exact diagnosis of a round cell sarcoma has a therapeutic relevance.

A Children's Oncology Group and TARGET initiative exploring the genetic landscape of Wilms tumor. | Office of Cancer Genomics

Science.gov (United States)

We performed genome-wide sequencing and analyzed mRNA and miRNA expression, DNA copy number, and DNA methylation in 117 Wilms tumors, followed by targeted sequencing of 651 Wilms tumors. In addition to genes previously implicated in Wilms tumors (WT1, CTNNB1, AMER1, DROSHA, DGCR8, XPO5, DICER1, SIX1, SIX2, MLLT1, MYCN, and TP53), we identified mutations in genes not previously recognized as recurrently involved in Wilms tumors, the most frequent being BCOR, BCORL1, NONO, MAX, COL6A3, ASXL1, MAP3K4, and ARID1A.

Pathologically decreased expression of miR-193a contributes to metastasis by targeting WT1-E-cadherin axis in non-small cell lung cancers

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Junjie Chen

2016-11-01

Full Text Available Abstract Background The metastatic cascade is a complex and multistep process with many potential barriers. Recently, miR-193a has been reported to be a suppressive miRNA in multiple types of cancers, but its underlying anti-oncogenic activity in non-small cell lung cancers (NSCLC is not fully elucidated. Methods The expressions of miR-193a (miR-193a-5p in human lung cancer tissues and cell lines were detected by real-time PCR. Dual-luciferase reporter assay was used to identify the direct target of miR-193a. Cell proliferation, apoptosis, and metastasis were assessed by CCK-8, flow cytometry, and Transwell assay, respectively. Results The expression of miR-193a in lung cancer tissues was decreased comparing to adjacent non-tumor tissues due to DNA hypermethylation in lung cancer tissues. Ectopic expression of miR-193a inhibited cell proliferation, colony formation, migration, and invasion in A549 and H1299 cells. Moreover, overexpression of miR-193a partially reversed tumor growth factor-β1 (TGF-β1-induced epithelial-to-mesenchymal transition (EMT in NSCLC cells. Mechanistically, miR-193a reduced the expression of WT1, which negatively regulated the protein level of E-cadherin, suggesting that miR-193a might prevent EMT via modulating WT1-E-cadherin axis. Importantly, knockdown of WT1 resembled the anti-cancer activity by miR-193a and overexpression of WT1 partially reversed miR-193a-induced anti-cancer activity, indicating that WT1 plays an important role in miR-193a-induced anti-cancer activity. Finally, overexpression of miR-193a decreased the growth of tumor xenografts in mice. Conclusion Collectively, our results have revealed an important role of miR-193a-WT1-E-cadherin axis in metastasis, demonstrated an important molecular cue for EMT, and suggested a therapeutic strategy of restoring miR-193a expression in NSCLC.

Differentiation-inducing factor-1 suppresses gene expression of cyclin D1 in tumor cells

International Nuclear Information System (INIS)

Yasmin, Tania; Takahashi-Yanaga, Fumi; Mori, Jun; Miwa, Yoshikazu; Hirata, Masato; Watanabe, Yutaka; Morimoto, Sachio; Sasaguri, Toshiyuki

2005-01-01

To determine the mechanism by which differentiation-inducing factor-1 (DIF-1), a morphogen of Dictyostelium discoideum, inhibits tumor cell proliferation, we examined the effect of DIF-1 on the gene expression of cyclin D1. DIF-1 strongly reduced the expression of cyclin D1 mRNA and correspondingly decreased the amount of β-catenin in HeLa cells and squamous cell carcinoma cells. DIF-1 activated glycogen synthase kinase-3β (GSK-3β) and inhibition of GSK-3β attenuated the DIF-1-induced β-catenin degradation, indicating the involvement of GSK-3β in this effect. Moreover, DIF-1 reduced the activities of T-cell factor (TCF)/lymphoid enhancer factor (LEF) reporter plasmid and a reporter gene driven by the human cyclin D1 promoter. Eliminating the TCF/LEF consensus site from the cyclin D1 promoter diminished the effect of DIF-1. These results suggest that DIF-1 inhibits Wnt/β-catenin signaling, resulting in the suppression of cyclin D1 promoter activity

Tumor Microenvironment Gene Signature as a Prognostic Classifier and Therapeutic Target

Science.gov (United States)

2016-06-01

AWARD NUMBER: W81XWH-14-1-0107 TITLE: Tumor Microenvironment Gene Signature as a Prognostic Classifier and Therapeutic Target PRINCIPAL...AND SUBTITLE Tumor Microenvironment Gene Signature as a 5a. CONTRACT NUMBER W81XWH-14-1-0107 Prognostic Classifier and Therapeutic Target 5b...gene signature that correlates with poor survival in ovarian cancer patients. We are refining this gene signature to develop biomarkers for the

Frequency of WT1 and 11p15 constitutional aberrations and phenotypic correlation in childhood Wilms tumour patients.

Science.gov (United States)

Segers, H; Kersseboom, R; Alders, M; Pieters, R; Wagner, A; van den Heuvel-Eibrink, M M

2012-11-01

In 9-17% of Wilms tumour patients a predisposing syndrome is present, in particular WT1-associated syndromes and overgrowth syndromes. Constitutional WT1 mutations or epigenetic changes on chromosome 11p15 have also been described in Wilms tumour patients without phenotypic abnormalities. Thus, the absence of phenotypic abnormalities does not exclude the presence of a genetic predisposition, suggesting that more Wilms tumour patients may have a constitutional abnormality. Therefore, we investigated the frequency of constitutional aberrations in combination with phenotype. Clinical genetic assessment, as well as molecular analysis of WT1 and locus 11p15 was offered to a single-centre cohort of 109 childhood Wilms tumour patients. Twelve patients (11%) had a WT1 aberration and eight patients (8%) had an 11p15 aberration. Of the 12 patients with a WT1 aberration, four had WAGR syndrome (Wilms tumor, aniridia, genitourinary malformations and mental retardation), one had Denys-Drash syndrome, four had genitourinary anomalies without other syndromic features and three had bilateral disease with stromal-predominant histology at young age without congenital anomalies. Of the eight patients with an 11p15 aberration, four had Beckwith-Wiedemann syndrome (BWS), two had minor features of BWS and two had no stigmata of BWS or hemihypertrophy. Constitutional WT1 or 11p15 aberrations are frequent in Wilms tumour patients and careful clinical assessment can identify the majority of these patients. Therefore, we would recommend offering clinical genetic counselling to all Wilms tumour patients, as well as molecular analysis to patients with clinical signs of a syndrome or with features that may indicate a constitutional WT1 or 11p15 aberration. Copyright © 2012 Elsevier Ltd. All rights reserved.

P53 function influences the effect of fractionated radiotherapy on glioblastoma tumors

International Nuclear Information System (INIS)

Haas-Kogan, Daphne A.; Kogan, Scott S.; Yount, Garret; Hsu, Jennie; Haas, Martin; Deen, Dennis F.; Israel, Mark A.

1999-01-01

Purpose: Glioblastoma multiforme brain tumors (GM) are treated with a spectrum of fractionation regimens based on the clinical and anatomical characteristics of the tumor but rarely based on the molecular characteristics of the individual neoplasm. This study tests the hypothesis that the response of cell lines derived from GM to fractionated radiotherapy depends on the function of wild-type p53 (wt p53), a tumor suppressor gene frequently mutated in GM tumors. Methods and Materials: Isogenic derivatives of glioblastoma cells differing only in p53 function were prepared using a retroviral vector expressing a dominant negative mutant of p53 (mt p53). Radiation survival in vitro was quantitated using linear quadratic and repair-saturation mathematical models. Apoptosis was assayed by a terminal deoxynucleotide transferase-labeling technique and chromatin morphology. Results: We have previously reported the generation of isogenic GM cell lines differing only in p53 function. U87-175.4, lacking wt p53 function, had a significantly lower α/β value than U87-LUX.8, expressing functional wt p53, leading us to hypothesize that fractionated irradiation would preferentially spare GM cells harboring mt p53 compared with those expressing functional, wt p53. Survival curves following either 2.0 Gy or 3.5 Gy/fraction demonstrated that lack of functional wt p53 was associated with resistance to fractionated irradiation. Radiation-induced apoptosis could not account for the observed differences in clonogenic survival. Rather, our data suggested that a deficit in the G1-checkpoint contributed to increased resistance to fractionated irradiation of cells expressing mutant p53. Conclusions: The effect of fractionated radiotherapy in GM may depend on the function of the tumor suppressor gene p53. A potential clinical consequence of these findings is that hyperfractionation regimens may provide a therapeutic advantage specifically for tumors expressing wt p53 whereas a radiotherapy

Generation of two modified mouse alleles of the Hic1 tumor suppressor gene

Czech Academy of Sciences Publication Activity Database

Pospíchalová, Vendula; Turečková, Jolana; Fafílek, Bohumil; Vojtěchová, Martina; Krausová, Michaela; Lukáš, Jan; Šloncová, Eva; Takacova, S.; Divoký, V.; Leprince, D.; Plachý, Jiří; Kořínek, Vladimír

2011-01-01

Roč. 49, č. 3 (2011), s. 142-151 ISSN 1526-954X R&D Projects: GA ČR(CZ) GA204/07/1567; GA ČR(CZ) GD204/09/H058 Institutional research plan: CEZ:AV0Z50520514 Keywords : Hypermethylated In Cancer 1 * Hic1 tumor suppressor * gene targeting Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.527, year: 2011

Steady state creep during metastable phase transition in Al-16 wt% Ag and Al-16 wt% Ag-0.1 wt% Zr alloys

Energy Technology Data Exchange (ETDEWEB)

Deaf, G.H.; Youssef, S.B.; Mahmoud, M.A. [Ain Shams Univ., Cairo (Egypt). Dept. of Physics

1998-08-16

The early stages of decomposition of Guinier-Preston zones (G.P. zones) in Al-16 wt% Ag and Al-16 wt% Ag-0.1 wt% Zr alloys were investigated through creep measurements and electron microscopy observations. It was found that the strengthening and softening of the alloys has been achieved during the formation of metastable phases (G.P. zones and {gamma}`-phase) in the ageing temperature range (428 to 498 K). TEM investigations confirmed that the addition of zirconium to the Al-Ag alloy accelerates the formation and coarsening of the metastable phases. The mean values of activation energy of both alloys were found to be equal to that quoted for precipitate-dislocation interactions. (orig.) 23 refs.

Differential evolution of a CXCR4-using HIV-1 strain in CCR5wt/wt and CCR5∆32/∆32 hosts revealed by longitudinal deep sequencing and phylogenetic reconstruction.

Science.gov (United States)

Le, Anh Q; Taylor, Jeremy; Dong, Winnie; McCloskey, Rosemary; Woods, Conan; Danroth, Ryan; Hayashi, Kanna; Milloy, M-J; Poon, Art F Y; Brumme, Zabrina L

2015-12-03

Rare individuals homozygous for a naturally-occurring 32 base pair deletion in the CCR5 gene (CCR5∆32/∆32) are resistant to infection by CCR5-using ("R5") HIV-1 strains but remain susceptible to less common CXCR4-using ("X4") strains. The evolutionary dynamics of X4 infections however, remain incompletely understood. We identified two individuals, one CCR5wt/wt and one CCR5∆32/∆32, within the Vancouver Injection Drug Users Study who were infected with a genetically similar X4 HIV-1 strain. While early-stage plasma viral loads were comparable in the two individuals (~4.5-5 log10 HIV-1 RNA copies/ml), CD4 counts in the CCR5wt/wt individual reached a nadir of 250 cells/mm(3) in the CCR5∆32/∆32 individual. Ancestral phylogenetic reconstructions using longitudinal envelope-V3 deep sequences suggested that both individuals were infected by a single transmitted/founder (T/F) X4 virus that differed at only one V3 site (codon 24). While substantial within-host HIV-1 V3 diversification was observed in plasma and PBMC in both individuals, the CCR5wt/wt individual's HIV-1 population gradually reverted from 100% X4 to ~60% R5 over ~4 years whereas the CCR5∆32/∆32 individual's remained consistently X4. Our observations illuminate early dynamics of X4 HIV-1 infections and underscore the influence of CCR5 genotype on HIV-1 V3 evolution.

Comparison of electrochemical performance of as-cast Pb-1 wt.% Sn and Pb-1 wt.% Sb alloys for lead-acid battery components

Energy Technology Data Exchange (ETDEWEB)

Osorio, Wislei R.; Peixoto, Leandro C.; Garcia, Amauri [Department of Materials Engineering, University of Campinas - UNICAMP, PO Box 612, 13083-970 Campinas, SP (Brazil)

2010-03-15

A comparative experimental study of the electrochemical features of as-cast Pb-1 wt.% Sn and Pb-1 wt.% Sb alloys is carried out with a view to applications in the manufacture of lead-acid battery components. The as-cast samples are obtained using a water-cooled unidirectional solidification system. Pb-Sn and Pb-Sb alloy samples having similar coarse cell arrays are subjected to corrosion tests in order to assess the effect of Sn or Sb segregation in the cell boundary on the electrochemical performance. Electrochemical impedance spectroscopy (EIS) diagrams, potentiodynamic polarization curves and an equivalent circuit analysis are used to evaluate the electrochemical parameters in a 0.5 M H{sub 2}SO{sub 4} solution at 25 C. Both the experimental and simulated EIS parameters evidence different kinetics of corrosion. The Pb-1 wt.% Sn alloy is found to have a current density which is of about three times lower than that of the Pb-1 wt.% Sb alloy which indicates that dilute Pb-Sn alloys have higher potential for application as positive grid material in maintenance-free Pb-acid batteries. (author)

ETS transcription factors control transcription of EZH2 and epigenetic silencing of the tumor suppressor gene Nkx3.1 in prostate cancer.

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Paolo Kunderfranco

2010-05-01

Full Text Available ETS transcription factors regulate important signaling pathways involved in cell differentiation and development in many tissues and have emerged as important players in prostate cancer. However, the biological impact of ETS factors in prostate tumorigenesis is still debated.We performed an analysis of the ETS gene family using microarray data and real-time PCR in normal and tumor tissues along with functional studies in normal and cancer cell lines to understand the impact in prostate tumorigenesis and identify key targets of these transcription factors. We found frequent dysregulation of ETS genes with oncogenic (i.e., ERG and ESE1 and tumor suppressor (i.e., ESE3 properties in prostate tumors compared to normal prostate. Tumor subgroups (i.e., ERG(high, ESE1(high, ESE3(low and NoETS tumors were identified on the basis of their ETS expression status and showed distinct transcriptional and biological features. ERG(high and ESE3(low tumors had the most robust gene signatures with both distinct and overlapping features. Integrating genomic data with functional studies in multiple cell lines, we demonstrated that ERG and ESE3 controlled in opposite direction transcription of the Polycomb Group protein EZH2, a key gene in development, differentiation, stem cell biology and tumorigenesis. We further demonstrated that the prostate-specific tumor suppressor gene Nkx3.1 was controlled by ERG and ESE3 both directly and through induction of EZH2.These findings provide new insights into the role of the ETS transcriptional network in prostate tumorigenesis and uncover previously unrecognized links between aberrant expression of ETS factors, deregulation of epigenetic effectors and silencing of tumor suppressor genes. The link between aberrant ETS activity and epigenetic gene silencing may be relevant for the clinical management of prostate cancer and design of new therapeutic strategies.

[Experimental study of interleukin-12 gene vaccines in the treatment of low-load malignant lymphoma (EL4)].

Science.gov (United States)

Jiang, Q; Da, W; Ou, Y

2001-11-01

Two kinds of murine interleukin-12 (mIL-12) fusion gene vaccines were used to treat the murine low-load malignant T cell lymphoma EL4 as minimal residual disease (MRD) model. C57BL/6 synergistical mice were subcutaneously inoculated with 1 x 10(6) wild-type (wt) EL4 tumor cells as low-load lymphoma model treated with two mIL-12 gene vaccines. Package cell line PA317/12 producing mIL-12 retrovirus (RV) was used as in vivo vaccine and EL4 tumor cells transferred with mIL-12 gene as ex vivo vaccine. In both mIL-12 gene vaccine-treated groups, there was no tumor growth in 50% mice 60 days after inoculation. Nine of these no tumor growth mice were re-challenged with 5 x 10(5) wt EL4 cells, and 5 of them survived without tumors in another 60 days. All control mice died with tumors within one month after inoculation. Among those developed tumors in both vaccine-treated groups, the development of tumors was delayed, the survival period prolonged (P EL4 MRD in C57BL/6 mice.

Tumor SHB gene expression affects disease characteristics in human acute myeloid leukemia.

Science.gov (United States)

Jamalpour, Maria; Li, Xiujuan; Cavelier, Lucia; Gustafsson, Karin; Mostoslavsky, Gustavo; Höglund, Martin; Welsh, Michael

2017-10-01

The mouse Shb gene coding for the Src Homology 2-domain containing adapter protein B has recently been placed in context of BCRABL1-induced myeloid leukemia in mice and the current study was performed in order to relate SHB to human acute myeloid leukemia (AML). Publicly available AML databases were mined for SHB gene expression and patient survival. SHB gene expression was determined in the Uppsala cohort of AML patients by qPCR. Cell proliferation was determined after SHB gene knockdown in leukemic cell lines. Despite a low frequency of SHB gene mutations, many tumors overexpressed SHB mRNA compared with normal myeloid blood cells. AML patients with tumors expressing low SHB mRNA displayed longer survival times. A subgroup of AML exhibiting a favorable prognosis, acute promyelocytic leukemia (APL) with a PMLRARA translocation, expressed less SHB mRNA than AML tumors in general. When examining genes co-expressed with SHB in AML tumors, four other genes ( PAX5, HDAC7, BCORL1, TET1) related to leukemia were identified. A network consisting of these genes plus SHB was identified that relates to certain phenotypic characteristics, such as immune cell, vascular and apoptotic features. SHB knockdown in the APL PMLRARA cell line NB4 and the monocyte/macrophage cell line MM6 adversely affected proliferation, linking SHB gene expression to tumor cell expansion and consequently to patient survival. It is concluded that tumor SHB gene expression relates to AML survival and its subgroup APL. Moreover, this gene is included in a network of genes that plays a role for an AML phenotype exhibiting certain immune cell, vascular and apoptotic characteristics.

[Study on genetic instability of nm23H1 gene in Chinese with original gallbladder tumor].

Science.gov (United States)

Lu, Hai Ying; Zhang, Guo Qiang; Li, Ji Cheng

2006-06-01

The aim of this study was to examine the microsatellite instability (MSI) and loss of heterozygosity (LOH) of locus D17S396 on chromosome 17 and their influence on the expression of nm23H1 in gallbladder tumors, which may provide experimental basis for the tumor occurrence and metastasis. Techniques such as DNA extraction from formalin-fixed paraffin-embedded tissues, polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP), ordinary silver stain were used to study MSI and LOH of locus D17S396. Envision immunohistochemistry and Leica-Qwin computer imaging techniques were used to assess the expression of gene nm23H1. In our experiment, the frequency of genetic instability of malignant gallbladder tumors was 42.55%, which was higher than that of gallbladder adenomas, while there were no genetic instability occurred in chronic cholecystitis tissue. The frequency of LOH seemed higher with the deteriorism of gallbladder tumor. Among 47 gallbladder carcinomas, the frequency of LOH and MSI were different between different differentiation cases (P gallbladder carcinoma, gallbladder adenoma and chronic cholecystitis tissue were different (P gallbladder carcinomas, the positive frequency of nm23H1 protein in LOH positive group was lower than that of LOH negative group (P gallbladder tumor. Both MSI and LOH of nm23H1 gene controlled the development of gallbladder tumor independently in different paths. MSI may be an early stage molecule marker of gallbladder carcinoma. LOH may be molecule marker for the deteriorism of gallbladder tissue, which could inhibit the expression of nm23H1 in local tissue of gallbladder carcinoma and endow it with high aggressive and poor prognosis. Increasing the amount of nm23H1 protein expression could effectively restrain gallbladder carcinoma metastasis and improve prognosis of patients.

Alternative polyadenylation of tumor suppressor genes in small intestinal neuroendocrine tumors.

Science.gov (United States)

Rehfeld, Anders; Plass, Mireya; Døssing, Kristina; Knigge, Ulrich; Kjær, Andreas; Krogh, Anders; Friis-Hansen, Lennart

2014-01-01

The tumorigenesis of small intestinal neuroendocrine tumors (SI-NETs) is poorly understood. Recent studies have associated alternative polyadenylation (APA) with proliferation, cell transformation, and cancer. Polyadenylation is the process in which the pre-messenger RNA is cleaved at a polyA site and a polyA tail is added. Genes with two or more polyA sites can undergo APA. This produces two or more distinct mRNA isoforms with different 3' untranslated regions. Additionally, APA can also produce mRNAs containing different 3'-terminal coding regions. Therefore, APA alters both the repertoire and the expression level of proteins. Here, we used high-throughput sequencing data to map polyA sites and characterize polyadenylation genome-wide in three SI-NETs and a reference sample. In the tumors, 16 genes showed significant changes of APA pattern, which lead to either the 3' truncation of mRNA coding regions or 3' untranslated regions. Among these, 11 genes had been previously associated with cancer, with 4 genes being known tumor suppressors: DCC, PDZD2, MAGI1, and DACT2. We validated the APA in three out of three cases with quantitative real-time-PCR. Our findings suggest that changes of APA pattern in these 16 genes could be involved in the tumorigenesis of SI-NETs. Furthermore, they also point to APA as a new target for both diagnostic and treatment of SI-NETs. The identified genes with APA specific to the SI-NETs could be further tested as diagnostic markers and drug targets for disease prevention and treatment.

Evaluation of promoter methylation status of MLH1 gene in Iranian patients with colorectal tumors and adenoma polyps.

Science.gov (United States)

Zarandi, Ashkan; Irani, Shiva; Savabkar, Sanaz; Chaleshi, Vahid; Ghavideldarestani, Maryam; Mirfakhraie, Reza; Khodadoostan, Mahsa; Nazemalhosseini-Mojarad, Ehsan; Asadzadeh Aghdaei, Hamid

2017-01-01

The aim of this study was to evaluate the methylation status of the promoter region of MLH1 gene in colorectal cancer (CRC) and its precursor lesions as well as elucidate its association with various clinicopathological characteristics among Iranian population. Epigenetic silencing of mismatch repair genes, such as MLH1 , by methylation of CpG islands of their promoter region has been proved to be an important mechanism in colorectal carcinogenesis. Fifty colorectal cancer and polyp tissue samples including 13 Primary colorectal tumor and 37 Adenoma polyp samples were enrolled in this study. Methylation-specific polymerase chain reaction (MSP) was performed to find the frequency of MLH1 Promoter Methylation. Promoter methylation of MLH1 gene was detected in 5 out of 13 tumor tissues and 4 out of 37 adenoma polyp. The frequency of MLH1 methylation in tumor samples was significantly higher compared to that in polyp tissues (P= 0.026). No significant association was observed between MLH1 promoter methylation and clinicopathological characteristics of the patients. The frequency of  MLH1  promoter methylation in CRC and colon polyp was 18%. Our findings indicated that methylation of MLH1 promoter region alone cannot be considered as a biomarker for early detection of CRC.

Assessment of Tumor Heterogeneity, as Evidenced by Gene Expression Profiles, Pathway Activation, and Gene Copy Number, in Patients with Multifocal Invasive Lobular Breast Tumors

Science.gov (United States)

Norton, Nadine; Advani, Pooja P.; Serie, Daniel J.; Geiger, Xochiquetzal J.; Necela, Brian M.; Axenfeld, Bianca C.; Kachergus, Jennifer M.; Feathers, Ryan W.; Carr, Jennifer M.; Crook, Julia E.; Moreno-Aspitia, Alvaro; Anastasiadis, Panos Z.; Perez, Edith A.; Thompson, E. Aubrey

2016-01-01

Background Invasive lobular carcinoma (ILC) comprises approximately ~10–20% of breast cancers. In general, multifocal/multicentric (MF/MC) breast cancer has been associated with an increased rate of regional lymph node metastases. Tumor heterogeneity between foci represents a largely unstudied source of genomic variation in those rare patients with MF/MC ILC. Methods We characterized gene expression and copy number in 2 or more foci from 11 patients with MF/MC ILC (all ER+, HER2-) and adjacent normal tissue. RNA and DNA were extracted from 3x1.5mm cores from all foci. Gene expression (730 genes) and copy number (80 genes) were measured using Nanostring PanCancer and Cancer CNV panels. Linear mixed models were employed to compare expression in tumor versus normal samples from the same patient, and to assess heterogeneity (variability) in expression among multiple ILC within an individual. Results 35 and 34 genes were upregulated (FC>2) and down-regulated (FC<0.5) respectively in ILC tumor relative to adjacent normal tissue, q<0.05. 9/34 down-regulated genes (FIGF, RELN, PROM1, SFRP1, MMP7, NTRK2, LAMB3, SPRY2, KIT) had changes larger than CDH1, a hallmark of ILC. Copy number changes in these patients were relatively few but consistent across foci within each patient. Amplification of three genes (CCND1, FADD, ORAOV1) at 11q13.3 was present in 2/11 patients in both foci. We observed significant evidence of within-patient between-foci variability (heterogeneity) in gene expression for 466 genes (p<0.05 with FDR 8%), including CDH1, FIGF, RELN, SFRP1, MMP7, NTRK2, LAMB3, SPRY2 and KIT. Conclusions There was substantial variation in gene expression between ILC foci within patients, including known markers of ILC, suggesting an additional level of complexity that should be addressed. PMID:27078887

Gene therapy and radiotherapy in malignant tumor

International Nuclear Information System (INIS)

Zhang Yaowen; Cao Yongzhen; Li Jin; Wang Qin

2008-01-01

Tumor treatment is one of the most important fields in medical research. Nowadays, a novel method which is combined gene therapy with radiotherapy plays an important role in the field of cancer research, and mainly includes immune gene therapy combined with radiotherapy, suicide gene therapy or tumor suppressor gene therapy combined with radiotherapy, antiangiogenesis gene therapy combined with radiotherapy and protective gene therapy combined with radiotherapy based on the technical features. This review summarized the current status of combined therapies of gene therapy and radiotherapy and possible mechanism. (authors)

ADAMS/WT advanced development - version 1.4 and beyond

Energy Technology Data Exchange (ETDEWEB)

Elliott, A.S.; Depauw, T.R. [Mechanical Dynamics, Inc., Mesa, AZ (United States)

1996-12-31

ADAMS/WT is an wind-turbine-specific shell for the general-purpose mechanical system simulation package ADAMS5. It was developed under the guidance of the National Renewable Energy Laboratory to give engineers and analysts in the wind turbine community access to the analytical power of ADAMS, without having to become expert in its particular technology. The 1.4 version of ADAMS/WT is the most recent upgrade to the package, incorporating the most up-to-date version of the AeroDyn aerodynamic forcing subroutines from the University of Utah. It is also the first version to be made available on the Windows/NT platform. In version 1.4, ADAMS/WT has been significantly improved throughout and runs much faster. Automatic generation of standardized output has been added. The documentation has been extensively augmented with more detailed descriptions, more figures and more examples. ADAMS/WT remains the most powerful analytical tool available for horizontal-axis wind turbine development. 10 figs.

A Children's Oncology Group and TARGET initiative exploring the genetic landscape of Wilms tumor.

Science.gov (United States)

Gadd, Samantha; Huff, Vicki; Walz, Amy L; Ooms, Ariadne H A G; Armstrong, Amy E; Gerhard, Daniela S; Smith, Malcolm A; Auvil, Jaime M Guidry; Meerzaman, Daoud; Chen, Qing-Rong; Hsu, Chih Hao; Yan, Chunhua; Nguyen, Cu; Hu, Ying; Hermida, Leandro C; Davidsen, Tanja; Gesuwan, Patee; Ma, Yussanne; Zong, Zusheng; Mungall, Andrew J; Moore, Richard A; Marra, Marco A; Dome, Jeffrey S; Mullighan, Charles G; Ma, Jing; Wheeler, David A; Hampton, Oliver A; Ross, Nicole; Gastier-Foster, Julie M; Arold, Stefan T; Perlman, Elizabeth J

2017-10-01

We performed genome-wide sequencing and analyzed mRNA and miRNA expression, DNA copy number, and DNA methylation in 117 Wilms tumors, followed by targeted sequencing of 651 Wilms tumors. In addition to genes previously implicated in Wilms tumors (WT1, CTNNB1, AMER1, DROSHA, DGCR8, XPO5, DICER1, SIX1, SIX2, MLLT1, MYCN, and TP53), we identified mutations in genes not previously recognized as recurrently involved in Wilms tumors, the most frequent being BCOR, BCORL1, NONO, MAX, COL6A3, ASXL1, MAP3K4, and ARID1A. DNA copy number changes resulted in recurrent 1q gain, MYCN amplification, LIN28B gain, and MIRLET7A loss. Unexpected germline variants involved PALB2 and CHEK2. Integrated analyses support two major classes of genetic changes that preserve the progenitor state and/or interrupt normal development.

A Children's Oncology Group and TARGET initiative exploring the genetic landscape of Wilms tumor

KAUST Repository

Gadd, Samantha

2017-08-21

We performed genome-wide sequencing and analyzed mRNA and miRNA expression, DNA copy number, and DNA methylation in 117 Wilms tumors, followed by targeted sequencing of 651 Wilms tumors. In addition to genes previously implicated in Wilms tumors (WT1, CTNNB1, AMER1, DROSHA, DGCR8, XPO5, DICER1, SIX1, SIX2, MLLT1, MYCN, and TP53), we identified mutations in genes not previously recognized as recurrently involved in Wilms tumors, the most frequent being BCOR, BCORL1, NONO, MAX, COL6A3, ASXL1, MAP3K4, and ARID1A. DNA copy number changes resulted in recurrent 1q gain, MYCN amplification, LIN28B gain, and MIRLET7A loss. Unexpected germline variants involved PALB2 and CHEK2. Integrated analyses support two major classes of genetic changes that preserve the progenitor state and/or interrupt normal development.

A Children's Oncology Group and TARGET initiative exploring the genetic landscape of Wilms tumor

KAUST Repository

Gadd, Samantha; Huff, Vicki; Walz, Amy L; Ooms, Ariadne H A G; Armstrong, Amy E; Gerhard, Daniela S; Smith, Malcolm A; Auvil, Jaime M Guidry; Meerzaman, Daoud; Chen, Qing-Rong; Hsu, Chih Hao; Yan, Chunhua; Nguyen, Cu; Hu, Ying; Hermida, Leandro C; Davidsen, Tanja; Gesuwan, Patee; Ma, Yussanne; Zong, Zusheng; Mungall, Andrew J; Moore, Richard A; Marra, Marco A; Dome, Jeffrey S; Mullighan, Charles G; Ma, Jing; Wheeler, David A; Hampton, Oliver A; Ross, Nicole; Gastier-Foster, Julie M; Arold, Stefan T.; Perlman, Elizabeth J

2017-01-01

We performed genome-wide sequencing and analyzed mRNA and miRNA expression, DNA copy number, and DNA methylation in 117 Wilms tumors, followed by targeted sequencing of 651 Wilms tumors. In addition to genes previously implicated in Wilms tumors (WT1, CTNNB1, AMER1, DROSHA, DGCR8, XPO5, DICER1, SIX1, SIX2, MLLT1, MYCN, and TP53), we identified mutations in genes not previously recognized as recurrently involved in Wilms tumors, the most frequent being BCOR, BCORL1, NONO, MAX, COL6A3, ASXL1, MAP3K4, and ARID1A. DNA copy number changes resulted in recurrent 1q gain, MYCN amplification, LIN28B gain, and MIRLET7A loss. Unexpected germline variants involved PALB2 and CHEK2. Integrated analyses support two major classes of genetic changes that preserve the progenitor state and/or interrupt normal development.

Telomere 1 (POT1) gene expression and its association with telomerase activity in colorectal tumor samples with different pathological features.

Science.gov (United States)

Izgi, Ahu; Gunal, Armagan; Yalcin, Serap; Gunduz, Ufuk

2014-09-01

The ends of chromosoms, telomeres are bound with a number of proteins which protect and stabilize telomeres against degredation, end to end fusion and aberrant recombinations. Telomeric DNA is bound of two groups of proteins, which are double-stranded telomeric DNA bindings proteins, and single stranded telomeric binding proteins. Among telomere binding proteins, protections of telomere 1 protein is a single stranded telomere binding proteins and suggested to be a significant player for telomere elongation and has an association with an enzyme called as telomerase which is an intrinsic reverse transcriptase. Telomerase synthesizes hexameric telomeric repeats onto the chromosomes thereby compansating telomere loss in immortal cells, such as tumor cells, whereas telomeres are shorthened with each division in normal cells. PCR-based TRAP (telomeric repeat amplification protocol) assay is a very sensitive assay for the detection of enzymatic activity of telomerase even if a few numbers of cancerous cells are available. The association between telomerase activity and hPOT1 expression in colorectal cancer is still unclear. Protein extraction was performed from specimens of matched normal and colorectal cancer specimens. Protein concentrations were determined by Bradford assay. Optimized protein concentrations were used for TRAP Assay. TRAP products were seperated by vertical gel electrophoresis on 12.5% polyacrylamide gels and visualized by silver staining. Gene expression of hPOT1 was determined by qPCR analysis. The results demonstrated that all tumor tissues were telomerase positive whereas all corresponding normal tissue was telomerase negative. Among clinicopathological findings, telomerase activity was found to be associated with stage, histology, localization, distant metastasis and lymph node metastasis of tumor in the current study. Although all of the clinicopathological findings differed in the expression of hPOT1 compared to normal tissues, they did not

Dose-dependent effects of calorie restriction on gene expression, metabolism, and tumor progression are partially mediated by insulin-like growth factor-1

International Nuclear Information System (INIS)

Nogueira, Leticia M; Lavigne, Jackie A; Chandramouli, Gadisetti V R; Lui, Huaitian; Barrett, J Carl; Hursting, Stephen D

2012-01-01

The prevalence of obesity, an established risk and progression factor for breast and many other cancer types, remains very high in the United States and throughout the world. Calorie restriction (CR), a reduced-calorie dietary regimen typically involving a 20–40% reduction in calorie consumption, prevents or reverses obesity, and inhibits mammary and other types of cancer in multiple tumor model systems. Unfortunately, the mechanisms underlying the tumor inhibitory effects of CR are poorly understood, and a better understanding of these mechanisms may lead to new intervention targets and strategies for preventing or controlling cancer. We have previously shown that the anticancer effects of CR are associated with decreased systemic levels of insulin-like growth factor-1 (IGF-1), the primary source of which is liver. We have also reported that CR strongly suppresses tumor development and growth in multiple mammary cancer models. To identify CR-responsive genes and pathways, and to further characterize the role of IGF-1 as a mediator of the anticancer effects of CR, we assessed hepatic and mammary gland gene expression, hormone levels and growth of orthotopically transplanted mammary tumors in control and CR mice with and without exogenous IGF-1. C57BL/6 mice were fed either control AIN-76A diet ad libitum (AL), subjected to 20%, 30%, or 40% CR plus placebo timed-release pellets, or subjected to 30% or 40% CR plus timed-release pellets delivering murine IGF-1 (mIGF-1, 20 μg/day). Compared with AL-fed controls, body weights were decreased 14.3% in the 20% CR group, 18.5% in the 30% CR group, and 38% in the 40% CR group; IGF-1 infusion had no effect on body weight. Hepatic transcriptome analyses indicated that compared with 20% CR, 30% CR significantly modulated more than twice the number of genes and 40% CR more than seven times the number of genes. Many of the genes specific to the 40% CR regimen were hepatic stress-related and/or DNA damage-related genes

Gene expression profile analysis of Ligon lintless-1 (Li1) mutant reveals important genes and pathways in cotton leaf and fiber development.

Science.gov (United States)

Ding, Mingquan; Jiang, Yurong; Cao, Yuefen; Lin, Lifeng; He, Shae; Zhou, Wei; Rong, Junkang

2014-02-10

Ligon lintless-1 (Li1) is a monogenic dominant mutant of Gossypium hirsutum (upland cotton) with a phenotype of impaired vegetative growth and short lint fibers. Despite years of research involving genetic mapping and gene expression profile analysis of Li1 mutant ovule tissues, the gene remains uncloned and the underlying pathway of cotton fiber elongation is still unclear. In this study, we report the whole genome-level deep-sequencing analysis of leaf tissues of the Li1 mutant. Differentially expressed genes in leaf tissues of mutant versus wild-type (WT) plants are identified, and the underlying pathways and potential genes that control leaf and fiber development are inferred. The results show that transcription factors AS2, YABBY5, and KANDI-like are significantly differentially expressed in mutant tissues compared with WT ones. Interestingly, several fiber development-related genes are found in the downregulated gene list of the mutant leaf transcriptome. These genes include heat shock protein family, cytoskeleton arrangement, cell wall synthesis, energy, H2O2 metabolism-related genes, and WRKY transcription factors. This finding suggests that the genes are involved in leaf morphology determination and fiber elongation. The expression data are also compared with the previously published microarray data of Li1 ovule tissues. Comparative analysis of the ovule transcriptomes of Li1 and WT reveals that a number of pathways important for fiber elongation are enriched in the downregulated gene list at different fiber development stages (0, 6, 9, 12, 15, 18dpa). Differentially expressed genes identified in both leaf and fiber samples are aligned with cotton whole genome sequences and combined with the genetic fine mapping results to identify a list of candidate genes for Li1. Copyright © 2013 Elsevier B.V. All rights reserved.

Primary microcephaly gene MCPH1 shows signatures of tumor suppressors and is regulated by miR-27a in oral squamous cell carcinoma.

Directory of Open Access Journals (Sweden)

Thejaswini Venkatesh

Full Text Available Mutations in the MCPH1 (microcephalin 1 gene, located at chromosome 8p23.1, result in two autosomal recessive disorders: primary microcephaly and premature chromosome condensation syndrome. MCPH1 has also been shown to be downregulated in breast, prostate and ovarian cancers, and mutated in 1/10 breast and 5/41 endometrial tumors, suggesting that it could also function as a tumor suppressor (TS gene. To test the possibility of MCPH1 as a TS gene, we first performed LOH study in a panel of 81 matched normal oral tissues and oral squamous cell carcinoma (OSCC samples, and observed that 14/71 (19.72% informative samples showed LOH, a hallmark of TS genes. Three protein truncating mutations were identified in 1/15 OSCC samples and 2/5 cancer cell lines. MCPH1 was downregulated at both the transcript and protein levels in 21/41 (51.22% and 19/25 (76% OSCC samples respectively. A low level of MCPH1 promoter methylation was also observed in 4/40 (10% tumor samples. We further observed that overexpression of MCPH1 decreased cellular proliferation, anchorage-independent growth in soft agar, cell invasion and tumor size in nude mice, indicating its tumor suppressive function. Using bioinformatic approaches and luciferase assay, we showed that the 3'-UTR of MCPH1 harbors two non-overlapping functional seed regions for miR-27a which negatively regulated its level. The expression level of miR-27a negatively correlated with the MCPH1 protein level in OSCC. Our study indicates for the first time that, in addition to its role in brain development, MCPH1 also functions as a tumor suppressor gene and is regulated by miR-27a.

Partial loss of heterozygosity events at the mutated gene in tumors from MLH1/MSH2 large genomic rearrangement carriers

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Zavodna, Katarina; Krivulcik, Tomas; Bujalkova, Maria Gerykova [Laboratory of Cancer Genetics, Cancer Research Institute of Slovak Academy of Sciences, Vlarska 7, 833 91 Bratislava (Slovakia); Slamka, Tomas; Martinicky, David; Ilencikova, Denisa [National Cancer Institute, Department of Oncologic Genetics, Klenova 1, 833 01 Bratislava (Slovakia); Bartosova, Zdena [Laboratory of Cancer Genetics, Cancer Research Institute of Slovak Academy of Sciences, Vlarska 7, 833 91 Bratislava (Slovakia)

2009-11-20

Depending on the population studied, large genomic rearrangements (LGRs) of the mismatch repair (MMR) genes constitute various proportions of the germline mutations that predispose to hereditary non-polyposis colorectal cancer (HNPCC). It has been reported that loss of heterozygosity (LOH) at the LGR region occurs through a gene conversion mechanism in tumors from MLH1/MSH2 deletion carriers; however, the converted tracts were delineated only by extragenic microsatellite markers. We sought to determine the frequency of LGRs in Slovak HNPCC patients and to study LOH in tumors from LGR carriers at the LGR region, as well as at other heterozygous markers within the gene to more precisely define conversion tracts. The main MMR genes responsible for HNPCC, MLH1, MSH2, MSH6, and PMS2, were analyzed by MLPA (multiplex ligation-dependent probe amplification) in a total of 37 unrelated HNPCC-suspected patients whose MLH1/MSH2 genes gave negative results in previous sequencing experiments. An LOH study was performed on six tumors from LGR carriers by combining MLPA to assess LOH at LGR regions and sequencing to examine LOH at 28 SNP markers from the MLH1 and MSH2 genes. We found six rearrangements in the MSH2 gene (five deletions and dup5-6), and one aberration in the MLH1 gene (del5-6). The MSH2 deletions were of three types (del1, del1-3, del1-7). We detected LOH at the LGR region in the single MLH1 case, which was determined in a previous study to be LOH-negative in the intragenic D3S1611 marker. Three tumors displayed LOH of at least one SNP marker, including two cases that were LOH-negative at the LGR region. LGRs accounted for 25% of germline MMR mutations identified in 28 Slovakian HNPCC families. A high frequency of LGRs among the MSH2 mutations provides a rationale for a MLPA screening of the Slovakian HNPCC families prior scanning by DNA sequencing. LOH at part of the informative loci confined to the MLH1 or MSH2 gene (heterozygous LGR region, SNP, or

Partial loss of heterozygosity events at the mutated gene in tumors from MLH1/MSH2 large genomic rearrangement carriers

Directory of Open Access Journals (Sweden)

Ilencikova Denisa

2009-11-01

Full Text Available Abstract Background Depending on the population studied, large genomic rearrangements (LGRs of the mismatch repair (MMR genes constitute various proportions of the germline mutations that predispose to hereditary non-polyposis colorectal cancer (HNPCC. It has been reported that loss of heterozygosity (LOH at the LGR region occurs through a gene conversion mechanism in tumors from MLH1/MSH2 deletion carriers; however, the converted tracts were delineated only by extragenic microsatellite markers. We sought to determine the frequency of LGRs in Slovak HNPCC patients and to study LOH in tumors from LGR carriers at the LGR region, as well as at other heterozygous markers within the gene to more precisely define conversion tracts. Methods The main MMR genes responsible for HNPCC, MLH1, MSH2, MSH6, and PMS2, were analyzed by MLPA (multiplex ligation-dependent probe amplification in a total of 37 unrelated HNPCC-suspected patients whose MLH1/MSH2 genes gave negative results in previous sequencing experiments. An LOH study was performed on six tumors from LGR carriers by combining MLPA to assess LOH at LGR regions and sequencing to examine LOH at 28 SNP markers from the MLH1 and MSH2 genes. Results We found six rearrangements in the MSH2 gene (five deletions and dup5-6, and one aberration in the MLH1 gene (del5-6. The MSH2 deletions were of three types (del1, del1-3, del1-7. We detected LOH at the LGR region in the single MLH1 case, which was determined in a previous study to be LOH-negative in the intragenic D3S1611 marker. Three tumors displayed LOH of at least one SNP marker, including two cases that were LOH-negative at the LGR region. Conclusion LGRs accounted for 25% of germline MMR mutations identified in 28 Slovakian HNPCC families. A high frequency of LGRs among the MSH2 mutations provides a rationale for a MLPA screening of the Slovakian HNPCC families prior scanning by DNA sequencing. LOH at part of the informative loci confined to the MLH1

Partial loss of heterozygosity events at the mutated gene in tumors from MLH1/MSH2 large genomic rearrangement carriers

International Nuclear Information System (INIS)

Zavodna, Katarina; Krivulcik, Tomas; Bujalkova, Maria Gerykova; Slamka, Tomas; Martinicky, David; Ilencikova, Denisa; Bartosova, Zdena

2009-01-01

Depending on the population studied, large genomic rearrangements (LGRs) of the mismatch repair (MMR) genes constitute various proportions of the germline mutations that predispose to hereditary non-polyposis colorectal cancer (HNPCC). It has been reported that loss of heterozygosity (LOH) at the LGR region occurs through a gene conversion mechanism in tumors from MLH1/MSH2 deletion carriers; however, the converted tracts were delineated only by extragenic microsatellite markers. We sought to determine the frequency of LGRs in Slovak HNPCC patients and to study LOH in tumors from LGR carriers at the LGR region, as well as at other heterozygous markers within the gene to more precisely define conversion tracts. The main MMR genes responsible for HNPCC, MLH1, MSH2, MSH6, and PMS2, were analyzed by MLPA (multiplex ligation-dependent probe amplification) in a total of 37 unrelated HNPCC-suspected patients whose MLH1/MSH2 genes gave negative results in previous sequencing experiments. An LOH study was performed on six tumors from LGR carriers by combining MLPA to assess LOH at LGR regions and sequencing to examine LOH at 28 SNP markers from the MLH1 and MSH2 genes. We found six rearrangements in the MSH2 gene (five deletions and dup5-6), and one aberration in the MLH1 gene (del5-6). The MSH2 deletions were of three types (del1, del1-3, del1-7). We detected LOH at the LGR region in the single MLH1 case, which was determined in a previous study to be LOH-negative in the intragenic D3S1611 marker. Three tumors displayed LOH of at least one SNP marker, including two cases that were LOH-negative at the LGR region. LGRs accounted for 25% of germline MMR mutations identified in 28 Slovakian HNPCC families. A high frequency of LGRs among the MSH2 mutations provides a rationale for a MLPA screening of the Slovakian HNPCC families prior scanning by DNA sequencing. LOH at part of the informative loci confined to the MLH1 or MSH2 gene (heterozygous LGR region, SNP, or

Expression of the MDR1 gene and P-glycoprotein in canine mast cell tumor cell lines

OpenAIRE

NAKAICHI, Munekazu; TAKESHITA, Yoko; OKUDA, Masaru; NAKAMOTO, Yuya; ITAMOTO, Kazuhito; UNE, Satoshi; SASAKI, Nobuo; KADOSAWA, Tsuyoshi; TAKAHASHI, Tomoko; TAURA, Yasuho

2007-01-01

Cellular drug resistance to antineoplastic drugs is often due to the presence of a drug efflux pump that reduces intracellular drug accumulation and chemosensitivity. P-glycoprotein (P-gp), which is encoded by the MDR1 gene, is considered to function as an ATP-driven membrane drug efflux pump and appears to play an important role in tumor cell resistance. In the present report, we assessed the expression of MDR1 by RT-PCR in three canine mast cell tumor cell lines, TiMC, CoMS and LuMC, origin...

Inhibition of TC-1 tumor progression by cotransfection of Saxatilin and IL-12 genes mediated by lipofection or electroporation.

Science.gov (United States)

Park, Y S; Kim, K S; Lee, Y K; Kim, J S; Baek, J Y; Huang, L

2009-01-01

Recently, a number of reports have demonstrated that coexpression of therapeutic genes having different anticancer mechanisms is a more effective strategy for anticancer gene therapy than single gene expression. Saxatilin, a novel disintegrin from snake venom, has recently been shown to have potent antiangiogenic functions, such as inhibition of platelet aggregation, bFGF-induced proliferation of HUVEC, and vitronectin-induced smooth muscle cell migration. IL-12 is a well-known immune modulator that promotes Thl-type antitumor immune responses and inhibits angiogenesis as well. The saxatilin and/or IL-12 genes were transfected intratumorally into C57BL/6 mice carrying TC-1 transformed mouse lung endothelial cells by either lipofection or electroporation. The plasmids encoding saxatilin and IL-12 were administered to tumor tissues via novel cationic liposomes consisting of dimyristyl-glutamyl-lysine (DMKE). On the other hand, expression of the genes was also induced by electroporation after naked pDNA injection to the tumor tissues. Lipofection of saxatilin and/or IL-12 genes appeared to be slightly more effective in inhibition of tumor growth than electroporation of the same genes. Cotransfection of saxatilin and IL-12 genes was clearly more effective than individual administration of either gene. This result implies that cotransfection of saxatilin and IL-12 genes represents an innovative modality for anticancer gene therapy.

Transcriptional profiles of SHH pathway genes in keratocystic odontogenic tumor and ameloblastoma.

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Gurgel, Clarissa Araújo Silva; Buim, Marcilei Eliza Cavichiolli; Carvalho, Kátia Cândido; Sales, Caroline Brandi Schlaepfer; Reis, Mitermayer Galvão; de Souza, Renata Oliveira; de Faro Valverde, Ludmila; de Azevedo, Roberto Almeida; Dos Santos, Jean Nunes; Soares, Fernando Augusto; Ramos, Eduardo Antônio Gonçalves

2014-09-01

Sonic hedgehog (SHH) pathway activation has been identified as a key factor in the development of many types of tumors, including odontogenic tumors. Our study examined the expression of genes in the SHH pathway to characterize their roles in the pathogenesis of keratocystic odontogenic tumors (KOT) and ameloblastomas (AB). We quantified the expression of SHH, SMO, PTCH1, SUFU, GLI1, CCND1, and BCL2 genes by qPCR in a total of 23 KOT, 11 AB, and three non-neoplastic oral mucosa (NNM). We also measured the expression of proteins related to this pathway (CCND1 and BCL2) by immunohistochemistry. We observed overexpression of SMO, PTCH1, GLI1, and CCND1 genes in both KOT (23/23) and AB (11/11). However, we did not detect expression of the SHH gene in 21/23 KOT and 10/11 AB tumors. Low levels of the SUFU gene were expressed in KOT (P = 0.0199) and AB (P = 0.0127) relative to the NNM. Recurrent KOT exhibited high levels of SMO (P = 0.035), PTCH1 (P = 0.048), CCND1 (P = 0.048), and BCL2 (P = 0.045) transcripts. Using immunolabeling of CCND1, we observed no statistical difference between primary and recurrent KOT (P = 0.8815), sporadic and NBCCS-KOT (P = 0.7688), and unicystic and solid AB (P = 0.7521). Overexpression of upstream (PTCH1 and SMO) and downstream (GLI1, CCND1 and BCL2) genes in the SHH pathway leads to the constitutive activation of this pathway in KOT and AB and may suggest a mechanism for the development of these types of tumors. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Brain metastasis of Wilms tumor with diffuse anaplasia and complex cytogenetic phenotype in a child with neurofibromatosis Type 1.

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Shvartsbeyn, Marianna; Bassani, Luigi; Mikolaenko, Irina; Wisoff, Jeffrey H

2011-10-01

The authors report the first case of a Wilms tumor (WT) with diffuse anaplasia metastatic to the brain in a 13-year-old girl with a history of neurofibromatosis Type 1. At presentation, the metastatic tumor had radiological features that suggested a meningioma. Histologically it was characterized by striking anaplasia and features similar to the patient's previously resected WT with diffuse anaplasia.

Thrombospondin-1 in a Murine Model of Colorectal Carcinogenesis.

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Zenaida P Lopez-Dee

Full Text Available Colorectal Cancer (CRC is one of the late complications observed in patients suffering from inflammatory bowel diseases (IBD. Carcinogenesis is promoted by persistent chronic inflammation occurring in IBD. Understanding the mechanisms involved is essential in order to ameliorate inflammation and prevent CRC. Thrombospondin 1 (TSP-1 is a multidomain glycoprotein with important roles in angiogenesis. The effects of TSP-1 in colonic tumor formation and growth were analyzed in a model of inflammation-induced carcinogenesis. WT and TSP-1 deficient mice (TSP-1-/- of the C57BL/6 strain received a single injection of azoxymethane (AOM and multiple cycles of dextran sodium sulfate (DSS to induce chronic inflammation-related cancers. Proliferation and angiogenesis were histologically analyzed in tumors. The intestinal transcriptome was also analyzed using a gene microarray approach. When the area containing tumors was compared with the entire colonic area of each mouse, the tumor burden was decreased in AOM/DSS-treated TSP-1-/- versus wild type (WT mice. However, these lesions displayed more angiogenesis and proliferation rates when compared with the WT tumors. AOM-DSS treatment of TSP-1-/- mice resulted in significant deregulation of genes involved in transcription, canonical Wnt signaling, transport, defense response, regulation of epithelial cell proliferation and metabolism. Microarray analyses of these tumors showed down-regulation of 18 microRNAs in TSP-1-/- tumors. These results contribute new insights on the controversial role of TSP-1 in cancer and offer a better understanding of the genetics and pathogenesis of CRC.

The prognostic value of ERCC1 and RRM1 gene expression in completely resected non-small cell lung cancer: tumor recurrence and overall survival

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Tantraworasin, Apichat; Saeteng, Somcharoen; Lertprasertsuke, Nirush; Arayawudhikul, Nuttapon; Kasemsarn, Choosak; Patumanond, Jayanton

2013-01-01

The roles of excision repair cross-complementing group 1 gene (ERCC1) expression and ribonucleotide reductase subunit M1 gene (RRM1) expression in completely resected non-small cell lung cancer (NSCLC) are still debatable. Previous studies have shown that both genes affected the overall survival and outcomes of patients who received platinum-based chemotherapy; however, some studies did not show this correlation. The aim of this study was to evaluate the prognostic values of ERCC1 and RRM1 gene expression in predicting tumor recurrence and overall survival in patients with completely resected NSCLC who received adjuvant chemotherapy and in those who did not. A retrospective cohort study was conducted in 247 patients with completely resected NSCLC. All patients had been treated with anatomic resection (lobectomy or pneumonectomy) with systematic mediastinal lymphadenectomy between January 2002 and December 2011 at Chiang Mai University Hospital, Chiang Mai, Thailand. They were divided into two groups: recurrence and no recurrence. Protein expression of ERCC1 and RRM1 was determined by immunohistochemistry. Correlations between clinicopathologic variables, including ERCC1 and RRM1 expression and tumor recurrence, were analyzed. Univariate and multivariate Cox proportional hazards regression analysis stratified by nodal involvement, tumor staging, intratumoral blood vessel invasion, intratumoral lymphatic invasion, and tumor necrosis was used to identify the prognostic roles of ERCC1 and RRM1. ERCC1 and RRM1 expression did not demonstrate prognostic value for tumor recurrence and overall survival in patients with completely resected NSCLC. In patients who did not receive adjuvant chemotherapy treatment, those with high ERCC1 and high RRM1 expression seemed to have greater potential for tumor recurrence and shorter overall survival than did those who had low ERCC1 and low RRM1 (hazard ratio [HR] =1.7, 95% confidence interval [CI] =0.6–4.3, P=0.292 and HR =1.6, 95% CI

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

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Tsujiuchi, Toshifumi; Shimizu, Kyoko; Onishi, Mariko; Sugata, Eriko; Fujii, Hiromasa; Mori, Toshio; Honoki, Kanya; Fukushima, Nobuyuki

2006-01-01

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

Tumor slices as a model to evaluate doxorubicin in vitro treatment and expression of trios of genes PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2 in canine mammary gland cancer

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Patrão Diogo FC

2008-07-01

Full Text Available Abstract Background In women with breast cancer submitted to neoadjuvant chemotherapy based in doxorubicin, tumor expression of groups of three genes (PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2 have classified them as responsive or resistant. We have investigated whether expression of these trios of genes could predict mammary carcinoma response in dogs and whether tumor slices, which maintain epithelial-mesenchymal interactions, could be used to evaluate drug response in vitro. Methods Tumors from 38 dogs were sliced and cultured with or without doxorubicin 1 μM for 24 h. Tumor cells were counted by two observers to establish a percentage variation in cell number, between slices. Based on these results, a reduction in cell number between treated and control samples ≥ 21.7%, arbitrarily classified samples, as drug responsive. Tumor expression of PRSS11, MTSS1, CLPTM1 and SMYD2, was evaluated by real time PCR. Relative expression results were then transformed to their natural logarithm values, which were spatially disposed according to the expression of trios of genes, comprising PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2. Fisher linear discrimination test was used to generate a separation plane between responsive and non-responsive tumors. Results Culture of tumor slices for 24 h was feasible. Nine samples were considered responsive and 29 non-responsive to doxorubicin, considering the pre-established cut-off value of cell number reduction ≥ 21.7%, between doxorubicin treated and control samples. Relative gene expression was evaluated and tumor samples were then spatially distributed according to the expression of the trios of genes: PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2. A separation plane was generated. However, no clear separation between responsive and non-responsive samples could be observed. Conclusion Three-dimensional distribution of samples according to the expression of the trios of genes PRSS11, MTSS1, CLPTM1 and

Von Hippel-Lindau tumor suppressor gene loss in renal cell carcinoma promotes oncogenic epidermal growth factor receptor signaling via Akt-1 and MEK-1.

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Lee, S Justin; Lattouf, Jean-Baptiste; Xanthopoulos, Julie; Linehan, W Marston; Bottaro, Donald P; Vasselli, James R

2008-10-01

Clear-cell renal cell carcinoma (RCC) is the most prevalent form of kidney cancer and is frequently associated with loss of von Hippel-Lindau (VHL) gene function, resulting in the aberrant transcriptional activation of genes that contribute to tumor growth and metastasis, including transforming growth factor-alpha (TGF-alpha), a ligand of the epidermal growth factor receptor (EGFR) tyrosine kinase. To determine the functional impact of EGFR activation on RCC, we suppressed critical components of this pathway: EGFR, Akt-1, and MEK-1. Stable transfection of RCC cells with plasmids bearing shRNA directed against each of these genes was used to individually suppress their expression. Transfectants were characterized for growth and invasiveness in vitro and tumorigenesis in vivo. RCC cell transfectants displayed significantly reduced growth rate and matrix invasion in vitro and RCC tumor xenograft growth rate in vivo. Analysis of tumor cells that emerged after extended periods in each model showed that significant EGFR suppression was sustained, whereas Akt-1 and MEK-1 knock-down cells had escaped shRNA suppression. EGFR, Akt-1, and MEK-1 are individually critical for RCC cell invasiveness in vitro and tumorigenicity in vivo, and even partial suppression of each can have a significant impact on tumor progression. The emergence of transfectants that had escaped Akt-1 and MEK-1 suppression during tumorigenicity experiments suggests that these effectors may each be more critical than EGFR for RCC tumorigenesis, consistent with results from clinical trials of EGFR inhibitors for RCC, where durable clinical responses have not been seen.

Von Hippel-Lindau Tumor Suppressor Gene Loss in Renal Cell Carcinoma Promotes Oncogenic Epidermal Growth Factor Receptor Signaling via Akt-1 and MEK1

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Lee, S. Justin; Lattouf, Jean-Baptiste; Xanthopoulos, Julie; Linehan, W. Marston; Bottaro, Donald P.; Vasselli, James R.

2008-01-01

Objectives Clear-cell renal cell carcinoma (RCC) is the most prevalent form of kidney cancer and is frequently associated with loss of von Hippel-Lindau (VHL) gene function, resulting in the aberrant transcriptional activation of genes that contribute to tumor growth and metastasis, including transforming growth factor-α (TGF-α), a ligand of the epidermal growth factor receptor (EGFR) tyrosine kinase. To determine the functional impact of EGFR activation on RCC, we suppressed critical components of this pathway: EGFR, Akt-1, and MEK-1. Methods Stable transfection of RCC cells with plasmids bearing shRNA directed against each of these genes was used to individually suppress their expression. Transfectants were characterized for growth and invasiveness in vitro and tumorigenesis in vivo. Results RCC cell transfectants displayed significantly reduced growth rate and matrix invasion in vitro and RCC tumor xenograft growth rate in vivo. Analysis of tumor cells that emerged after extended periods in each model showed that significant EGFR suppression was sustained, whereas Akt-1 and MEK-1 knockdown cells had escaped shRNA suppression. Conclusions EGFR, Akt-1, and MEK-1 are individually critical for RCC cell invasiveness in vitro and tumorigenicity in vivo, and even partial suppression of each can have a significant impact on tumor progression. The emergence of transfectants that had escaped Akt-1 and MEK-1 suppression during tumorigenicity experiments suggests that these effectors may each be more critical than EGFR for RCC tumorigenesis, consistent with results from clinical trials of EGFR inhibitors for RCC, where durable clinical responses have not been seen. PMID:18243508

AZU-1: A Candidate Breast Tumor Suppressor and Biomarker for Tumor Progression

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Chen, Huei-Mei; Schmeichel, Karen L; Mian, I. Saira; Lelie`vre, Sophie; Petersen, Ole W; Bissell, Mina J

2000-02-04

To identify genes misregulated in the final stages of breast carcinogenesis, we performed differential display to compare the gene expression patterns of the human tumorigenic mammary epithelial cells, HMT-3522-T4-2, with those of their immediate premalignant progenitors, HMT-3522-S2. We identified a novel gene, called anti-zuai-1 (AZU-1), that was abundantly expressed in non- and premalignant cells and tissues but was appreciably reduced in breast tumor cell types and in primary tumors. The AZU-1 gene encodes an acidic 571-amino-acid protein containing at least two structurally distinct domains with potential protein-binding functions: an N-terminal serine and proline-rich domain with a predicted immunoglobulin-like fold and a C-terminal coiled-coil domain. In HMT-3522 cells, the bulk of AZU-1 protein resided in a detergent-extractable cytoplasmic pool and was present at much lower levels in tumorigenic T4-2 cells than in their nonmalignant counterparts. Reversion of the tumorigenic phenotype of T4-2 cells, by means described previously, was accompanied by the up-regulation of AZU-1. In addition, reexpression of AZU-1 in T4-2 cells, using viral vectors, was sufficient to reduce their malignant phenotype substantially, both in culture and in vivo. These results indicate that AZU-1 is a candidate breast tumor suppressor that may exert its effects by promoting correct tissue morphogenesis.

Expression Profile of Genes Related to Drug Metabolism in Human Brain Tumors.

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Pantelis Stavrinou

Full Text Available Endogenous and exogenous compounds as well as carcinogens are metabolized and detoxified by phase I and II enzymes, the activity of which could be crucial to the inactivation and hence susceptibility to carcinogenic factors. The expression of these enzymes in human brain tumor tissue has not been investigated sufficiently. We studied the association between tumor pathology and the expression profile of seven phase I and II drug metabolizing genes (CYP1A1, CYP1B1, ALDH3A1, AOX1, GSTP1, GSTT1 and GSTM3 and some of their proteins.Using qRT-PCR and western blotting analysis the gene and protein expression in a cohort of 77 tumors were investigated. The major tumor subtypes were meningioma, astrocytoma and brain metastases, -the later all adenocarcinomas from a lung primary.Meningeal tumors showed higher expression levels for AOX1, CYP1B1, GSTM3 and GSTP1. For AOX1, GSTM and GSTP1 this could be verified on a protein level as well. A negative correlation between the WHO degree of malignancy and the strength of expression was identified on both transcriptional and translational level for AOX1, GSTM3 and GSTP1, although the results could have been biased by the prevalence of meningiomas and glioblastomas in the inevitably bipolar distribution of the WHO grades. A correlation between the gene expression and the protein product was observed for AOX1, GSTP1 and GSTM3 in astrocytomas.The various CNS tumors show different patterns of drug metabolizing gene expression. Our results suggest that the most important factor governing the expression of these enzymes is the histological subtype and to a far lesser extent the degree of malignancy itself.

Efficacy of ONC201 in Desmoplastic Small Round Cell Tumor.

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Hayes-Jordan, Andrea A; Ma, Xiao; Menegaz, Brian A; Lamhamedi-Cherradi, Salah-Eddine; Kingsley, Charles V; Benson, Jalen A; Camacho, Pamela E; Ludwig, Joseph A; Lockworth, Cynthia R; Garcia, Gloria E; Craig, Suzanne L

2018-05-01

Desmoplastic Small Round Cell Tumor (DSRCT) is a rare sarcoma tumor of adolescence and young adulthood, which harbors a recurrent chromosomal translocation between the Ewing's sarcoma gene (EWSR1) and the Wilms' tumor suppressor gene (WT1). Patients usually develop multiple abdominal tumors with liver and lymph node metastasis developing later. Survival is poor using a multimodal therapy that includes chemotherapy, radiation and surgical resection, new therapies are needed for better management of DSRCT. Triggering cell apoptosis is the scientific rationale of many cancer therapies. Here, we characterized for the first time the expression of pro-apoptotic receptors, tumor necrosis-related apoptosis-inducing ligand receptors (TRAILR1-4) within an established human DSRCT cell line and clinical samples. The molecular induction of TRAIL-mediated apoptosis using agonistic small molecule, ONC201 in vitro cell-based proliferation assay and in vivo novel orthotopic xenograft animal models of DSRCT, was able to inhibit cell proliferation that was associated with caspase activation, and tumor growth, indicating that a cell-based delivery of an apoptosis-inducing factor could be relevant therapeutic agent to control DSRCT. Copyright © 2018. Published by Elsevier Inc.

Efficacy of ONC201 in Desmoplastic Small Round Cell Tumor

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Andrea A. Hayes-Jordan

2018-05-01

Full Text Available Desmoplastic Small Round Cell Tumor (DSRCT is a rare sarcoma tumor of adolescence and young adulthood, which harbors a recurrent chromosomal translocation between the Ewing’s sarcoma gene (EWSR1 and the Wilms’ tumor suppressor gene (WT1. Patients usually develop multiple abdominal tumors with liver and lymph node metastasis developing later. Survival is poor using a multimodal therapy that includes chemotherapy, radiation and surgical resection, new therapies are needed for better management of DSRCT. Triggering cell apoptosis is the scientific rationale of many cancer therapies. Here, we characterized for the first time the expression of pro-apoptotic receptors, tumor necrosis-related apoptosis-inducing ligand receptors (TRAILR1-4 within an established human DSRCT cell line and clinical samples. The molecular induction of TRAIL-mediated apoptosis using agonistic small molecule, ONC201 in vitro cell-based proliferation assay and in vivo novel orthotopic xenograft animal models of DSRCT, was able to inhibit cell proliferation that was associated with caspase activation, and tumor growth, indicating that a cell-based delivery of an apoptosis-inducing factor could be relevant therapeutic agent to control DSRCT.

Gene expression patterns in pancreatic tumors, cells and tissues.

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Anson W Lowe

2007-03-01

Full Text Available Cancers of the pancreas originate from both the endocrine and exocrine elements of the organ, and represent a major cause of cancer-related death. This study provides a comprehensive assessment of gene expression for pancreatic tumors, the normal pancreas, and nonneoplastic pancreatic disease.DNA microarrays were used to assess the gene expression for surgically derived pancreatic adenocarcinomas, islet cell tumors, and mesenchymal tumors. The addition of normal pancreata, isolated islets, isolated pancreatic ducts, and pancreatic adenocarcinoma cell lines enhanced subsequent analysis by increasing the diversity in gene expression profiles obtained. Exocrine, endocrine, and mesenchymal tumors displayed unique gene expression profiles. Similarities in gene expression support the pancreatic duct as the origin of adenocarcinomas. In addition, genes highly expressed in other cancers and associated with specific signal transduction pathways were also found in pancreatic tumors.The scope of the present work was enhanced by the inclusion of publicly available datasets that encompass a wide spectrum of human tissues and enabled the identification of candidate genes that may serve diagnostic and therapeutic goals.

Tumor-specific loss of 11p15.5 alleles in del11p13 Wilms tumor and in familial adrenocortical carcinoma

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Henry, I.; Grandjouan, S.; Couillin, P.

1989-01-01

The authors have compared constitutional and tumor genotypes in nine cases of hereditary Wilms tumor (WT) and in three unrelated cases of familial adrenocortical carcinoma (ADCC). Since susceptibility to these tumors can be observed in malformation syndromes associated with a constitutional deletion of band 11p13 (WT) and with a constitutional duplication of band 11p15.5 (WT, ADCC), they investigated these two candidate regions by using 11p polymorphic markers. As expected, somatic chromosomal events, resulting in a loss of heterozygosity limited to region 11p15.5, were observed in the tumor of two familial cases of adrenocortical carcinoma. Surprisingly, however, analysis of the WT of two patients with a constitutional deletion of band 11p13, associated with aniridia, genitourinary abnormalities, and mental retardation (WAGR syndrome), revealed a loss of heterozygosity limited to region 11p15.5. These data therefore suggest that observation of a specific loss of heterozygosity may not necessarily point to the site of the initial germinal mutation. Together with previous similar observations of a loss of heterozygosity limited to 11p15.5 in breast cancer and in rhabdomyosarcoma, the data suggest that region 11p15.5 may carry a non-tissue-specific gene that could be involved in genetic predisposition, in tumor progression, or in both

Can T1 w/T2 w ratio be used as a myelin-specific measure in subcortical structures? Comparisons between FSE-based T1 w/T2 w ratios, GRASE-based T1 w/T2 w ratios and multi-echo GRASE-based myelin water fractions.

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Uddin, Md Nasir; Figley, Teresa D; Marrie, Ruth Ann; Figley, Chase R

2018-03-01

Given the growing popularity of T 1 -weighted/T 2 -weighted (T 1 w/T 2 w) ratio measurements, the objective of the current study was to evaluate the concordance between T 1 w/T 2 w ratios obtained using conventional fast spin echo (FSE) versus combined gradient and spin echo (GRASE) sequences for T 2 w image acquisition, and to compare the resulting T 1 w/T 2 w ratios with histologically validated myelin water fraction (MWF) measurements in several subcortical brain structures. In order to compare these measurements across a relatively wide range of myelin concentrations, whole-brain T 1 w magnetization prepared rapid acquisition gradient echo (MPRAGE), T 2 w FSE and three-dimensional multi-echo GRASE data were acquired from 10 participants with multiple sclerosis at 3 T. Then, after high-dimensional, non-linear warping, region of interest (ROI) analyses were performed to compare T 1 w/T 2 w ratios and MWF estimates (across participants and brain regions) in 11 bilateral white matter (WM) and four bilateral subcortical grey matter (SGM) structures extracted from the JHU_MNI_SS 'Eve' atlas. Although the GRASE sequence systematically underestimated T 1 w/T 2 w values compared to the FSE sequence (revealed by Bland-Altman and mountain plots), linear regressions across participants and ROIs revealed consistently high correlations between the two methods (r 2 = 0.62 for all ROIs, r 2 = 0.62 for WM structures and r 2 = 0.73 for SGM structures). However, correlations between either FSE-based or GRASE-based T 1 w/T 2 w ratios and MWFs were extremely low in WM structures (FSE-based, r 2 = 0.000020; GRASE-based, r 2 = 0.0014), low across all ROIs (FSE-based, r 2 = 0.053; GRASE-based, r 2 = 0.029) and moderate in SGM structures (FSE-based, r 2 = 0.20; GRASE-based, r 2 = 0.17). Overall, our findings indicated a high degree of correlation (but not equivalence) between FSE-based and GRASE-based T 1 w/T 2 w ratios, and low correlations between T 1 w/T 2 w ratios and MWFs. This

Genetic and Genomic Characterization of 462 Melanoma Patient-Derived Xenografts, Tumor Biopsies, and Cell Lines

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Bradley Garman

2017-11-01

Full Text Available Summary: Tumor-sequencing studies have revealed the widespread genetic diversity of melanoma. Sequencing of 108 genes previously implicated in melanomagenesis was performed on 462 patient-derived xenografts (PDXs, cell lines, and tumors to identify mutational and copy number aberrations. Samples came from 371 unique individuals: 263 were naive to treatment, and 108 were previously treated with targeted therapy (34, immunotherapy (54, or both (20. Models of all previously reported major melanoma subtypes (BRAF, NRAS, NF1, KIT, and WT/WT/WT were identified. Multiple minor melanoma subtypes were also recapitulated, including melanomas with multiple activating mutations in the MAPK-signaling pathway and chromatin-remodeling gene mutations. These well-characterized melanoma PDXs and cell lines can be used not only as reagents for a large array of biological studies but also as pre-clinical models to facilitate drug development. : Garman et al. have characterized melanoma PDXs and cell lines described in Krepler et al. (see the related paper in this issue of Cell Reports, identifying major and minor subtypes, some of which were previously not well defined, targeted and immunotherapy resistance, and tumor heterogeneity, creating a set of reagents for future drug discovery and biological studies. Keywords: melanoma, patient-derived xenografts, massively parallel sequencing, cell lines

Expression of iron-related genes in human brain and brain tumors

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Britton Robert S

2009-04-01

Full Text Available Abstract Background Defective iron homeostasis may be involved in the development of some diseases within the central nervous system. Although the expression of genes involved in normal iron balance has been intensively studied in other tissues, little is known about their expression in the brain. We investigated the mRNA levels of hepcidin (HAMP, HFE, neogenin (NEO1, transferrin receptor 1 (TFRC, transferrin receptor 2 (TFR2, and hemojuvelin (HFE2 in normal human brain, brain tumors, and astrocytoma cell lines. The specimens included 5 normal brain tissue samples, 4 meningiomas, one medulloblastoma, 3 oligodendrocytic gliomas, 2 oligoastrocytic gliomas, 8 astrocytic gliomas, and 3 astrocytoma cell lines. Results Except for hemojuvelin, all genes studied had detectable levels of mRNA. In most tumor types, the pattern of gene expression was diverse. Notable findings include high expression of transferrin receptor 1 in the hippocampus and medulla oblongata compared to other brain regions, low expression of HFE in normal brain with elevated HFE expression in meningiomas, and absence of hepcidin mRNA in astrocytoma cell lines despite expression in normal brain and tumor specimens. Conclusion These results indicate that several iron-related genes are expressed in normal brain, and that their expression may be dysregulated in brain tumors.

Predicting survival in patients with metastatic kidney cancer by gene-expression profiling in the primary tumor.

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Vasselli, James R; Shih, Joanna H; Iyengar, Shuba R; Maranchie, Jodi; Riss, Joseph; Worrell, Robert; Torres-Cabala, Carlos; Tabios, Ray; Mariotti, Andra; Stearman, Robert; Merino, Maria; Walther, McClellan M; Simon, Richard; Klausner, Richard D; Linehan, W Marston

2003-06-10

To identify potential molecular determinants of tumor biology and possible clinical outcomes, global gene-expression patterns were analyzed in the primary tumors of patients with metastatic renal cell cancer by using cDNA microarrays. We used grossly dissected tumor masses that included tumor, blood vessels, connective tissue, and infiltrating immune cells to obtain a gene-expression "profile" from each primary tumor. Two patterns of gene expression were found within this uniformly staged patient population, which correlated with a significant difference in overall survival between the two patient groups. Subsets of genes most significantly associated with survival were defined, and vascular cell adhesion molecule-1 (VCAM-1) was the gene most predictive for survival. Therefore, despite the complex biological nature of metastatic cancer, basic clinical behavior as defined by survival may be determined by the gene-expression patterns expressed within the compilation of primary gross tumor cells. We conclude that survival in patients with metastatic renal cell cancer can be correlated with the expression of various genes based solely on the expression profile in the primary kidney tumor.

MDM2 SNP309, gene-gene interaction, and tumor susceptibility: an updated meta-analysis

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Wu Wei

2011-05-01

Full Text Available Abstract Background The tumor suppressor gene p53 is involved in multiple cellular pathways including apoptosis, transcriptional control, and cell cycle regulation. In the last decade it has been demonstrated that the single nucleotide polymorphism (SNP at codon 72 of the p53 gene is associated with the risk for development of various neoplasms. MDM2 SNP309 is a single nucleotide T to G polymorphism located in the MDM2 gene promoter. From the time that this well-characterized functional polymorphism was identified, a variety of case-control studies have been published that investigate the possible association between MDM2 SNP309 and cancer risk. However, the results of the published studies, as well as the subsequent meta-analyses, remain contradictory. Methods To investigate whether currently published epidemiological studies can clarify the potential interaction between MDM2 SNP309 and the functional genetic variant in p53 codon72 (Arg72Pro and p53 mutation status, we performed a meta-analysis of the risk estimate on 27,813 cases with various tumor types and 30,295 controls. Results The data we reviewed indicated that variant homozygote 309GG and heterozygote 309TG were associated with a significant increased risk of all tumor types (homozygote comparison: odds ratio (OR = 1.25, 95% confidence interval (CI = 1.13-1.37; heterozygote comparison: OR = 1.10, 95% CI = 1.03-1.17. We also found that the combination of GG and Pro/Pro, TG and Pro/Pro, GG and Arg/Arg significantly increased the risk of cancer (OR = 3.38, 95% CI = 1.77-6.47; OR = 1.88, 95% CI = 1.26-2.81; OR = 1.96, 95% CI = 1.01-3.78, respectively. In a stratified analysis by tumor location, we also found a significant increased risk in brain, liver, stomach and uterus cancer (OR = 1.47, 95% CI = 1.06-2.03; OR = 2.24, 95%CI = 1.57-3.18; OR = 1.54, 95%CI = 1.04-2.29; OR = 1.34, 95%CI = 1.07-1.29, respectively. However, no association was seen between MDM2 SNP309 and tumor susceptibility

Molecular biology III - Oncogenes and tumor suppressor genes

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Giaccia, Amato J.

1996-01-01

Purpose: The purpose of this course is to introduce to radiation oncologists the basic concepts of tumorigenesis, building on the information that will be presented in the first and second part of this series of lectures. Objective: Our objective is to increase the current understanding of radiation oncologists with the process of tumorigenesis, especially focusing on genes that are altered in many tumor types that are potential candidates for novel molecular strategies. As strategies to treat cancer of cancer are becoming more sophisticated, it will be important for both the practitioner and academician to develop a basic understanding of the function of cancer 'genes'. This will be the third in a series of refresher courses that are meant to address recent advances in Cancer Biology in a way that both clinicians without previous knowledge of molecular biology or experienced researchers will find interesting. The lecture will begin with a basic overview of tumorigenesis; methods of detecting chromosome/DNA alterations, approaches used to isolate oncogenes and tumor suppressor genes, and their role in cell killing by apoptosis. Special attention will be given to oncogenes and tumor suppressor genes that are modulated by ionizing radiation and the tumor microenvironment. We will relate the biology of oncogenes and tumor suppressor genes to basic aspects of radiation biology that would be important in clinical practice. Finally, we will review recent studies on the prognostic significance of p53 mutations and apoptosis in tumor specimens. The main point of this lecture is to relate both researcher and clinician what are the therapeutic ramifications of oncogene and tumor suppressor gene mutations found in human neoptasia

Hypoxic resistance of KRAS mutant tumor cells to 3-Bromopyruvate is counteracted by Prima-1 and reversed by N-acetylcysteine.

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Orue, Andrea; Chavez, Valery; Strasberg-Rieber, Mary; Rieber, Manuel

2016-11-18

The metabolic inhibitor 3-bromopyruvate (3-BrPA) is a promising anti-cancer alkylating agent, shown to inhibit growth of some colorectal carcinoma with KRAS mutation. Recently, we demonstrated increased resistance to 3-BrPA in wt p53 tumor cells compared to those with p53 silencing or mutation. Since hypoxic microenvironments select for tumor cells with diminished therapeutic response, we investigated whether hypoxia unequally increases resistance to 3-BrPA in wt p53 MelJuso melanoma harbouring (Q61L)-mutant NRAS and wt BRAF, C8161 melanoma with (G12D)-mutant KRAS (G464E)-mutant BRAF, and A549 lung carcinoma with a KRAS (G12S)-mutation. Since hypoxia increases the toxicity of the p53 activator, Prima-1 against breast cancer cells irrespective of their p53 status, we also investigated whether Prima-1 reversed hypoxic resistance to 3-BrPA. In contrast to the high susceptibility of hypoxic mutant NRAS MelJuso cells to 3-BrPA or Prima-1, KRAS mutant C8161 and A549 cells revealed hypoxic resistance to 3-BrPA counteracted by Prima-1. In A549 cells, Prima-1 increased p21CDKN1mRNA, and reciprocally inhibited mRNA expression of the SLC2A1-GLUT1 glucose transporter-1 and ALDH1A1, gene linked to detoxification and stem cell properties. 3-BrPA lowered CAIX and VEGF mRNA expression. Death from joint Prima-1 and 3-BrPA treatment in KRAS mutant A549 and C8161 cells seemed mediated by potentiating oxidative stress, since it was antagonized by the anti-oxidant and glutathione precursor N-acetylcysteine. This report is the first to show that Prima-1 kills hypoxic wt p53 KRAS-mutant cells resistant to 3-BrPA, partly by decreasing GLUT-1 expression and exacerbating pro-oxidant stress.

Basic fibroblast growth factor in an animal model of spontaneous mammary tumor progression.

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Kao, Steven; Mo, Jeffrey; Baird, Andrew; Eliceiri, Brian P

2012-06-01

Although basic fibroblast growth factor (FGF2) was the first pro-angiogenic molecule discovered, it has numerous activities on the growth and differentiation of non-vascular cell types. FGF2 is both stimulatory and inhibitory, depending on the cell type evaluated, the experimental design used and the context in which it is tested. Here, we investigated the effects of manipulating endogenous FGF2 on the development of mammary cancer to determine whether its endogenous contribution in vivo is pro- or anti-tumorigenic. Specifically, we examined the effects of FGF2 gene dosing in a cross between a spontaneous breast tumor model (PyVT+ mice) and FGF2-/- (FGF KO) mice. Using these mice, the onset and progression of mammary tumors was determined. As predicted, female FGF2 WT mice developed mammary tumors starting around 60 days after birth and by 80 days, 100% of FGF2 WT female mice had mammary tumors. In contrast, 80% of FGF2 KO female mice had no palpable tumors until nearly three weeks later (85 days) at times when 100% of the WT cohort was tumor positive. All FGF KO mice were tumor-bearing by 115 days. When we compared the onset of mammary tumor development and the tumor progression curves between FGF het and FGF KO mice, we observed a difference, which suggested a gene dosing effect. Analysis of the tumors demonstrated that there were significant differences in tumor size depending on FGF2 status. The delay in tumor onset supports a functional role for FGF2 in mammary tumor progression, but argues against an essential role for FGF2 in overall mammary tumor progression.

DNA Methylation and Gene Expression Profiling of Ewing Sarcoma Primary Tumors Reveal Genes That Are Potential Targets of Epigenetic Inactivation

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Nikul Patel

2012-01-01

Full Text Available The role of aberrant DNA methylation in Ewing sarcoma is not completely understood. The methylation status of 503 genes in 52 formalin-fixed paraffin-embedded EWS tumors and 3 EWS cell lines was compared to human mesenchymal stem cell primary cultures (hMSCs using bead chip methylation analysis. Relative expression of methylated genes was assessed in 5-Aza-2-deoxycytidine-(5-AZA-treated EWS cell lines and in a cohort of primary EWS samples and hMSCs by gene expression and quantitative RT-PCR. 129 genes demonstrated statistically significant hypermethylation in EWS tumors compared to hMSCs. Thirty-six genes were profoundly methylated in EWS and unmethylated in hMSCs. 5-AZA treatment of EWS cell lines resulted in upregulation of expression of hundreds of genes including 162 that were increased by at least 2-fold. The expression of 19 of 36 candidate hypermethylated genes was increased following 5-AZA. Analysis of gene expression from an independent cohort of tumors confirmed decreased expression of six of nineteen hypermethylated genes (AXL, COL1A1, CYP1B1, LYN, SERPINE1, and VCAN. Comparing gene expression and DNA methylation analyses proved to be an effective way to identify genes epigenetically regulated in EWS. Further investigation is ongoing to elucidate the role of these epigenetic alterations in EWS pathogenesis.

Combining miRNA and mRNA Expression Profiles in Wilms Tumor Subtypes

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Nicole Ludwig

2016-03-01

Full Text Available Wilms tumor (WT is the most common childhood renal cancer. Recent findings of mutations in microRNA (miRNA processing proteins suggest a pivotal role of miRNAs in WT genesis. We performed miRNA expression profiling of 36 WTs of different subtypes and four normal kidney tissues using microarrays. Additionally, we determined the gene expression profile of 28 of these tumors to identify potentially correlated target genes and affected pathways. We identified 85 miRNAs and 2107 messenger RNAs (mRNA differentially expressed in blastemal WT, and 266 miRNAs and 1267 mRNAs differentially expressed in regressive subtype. The hierarchical clustering of the samples, using either the miRNA or mRNA profile, showed the clear separation of WT from normal kidney samples, but the miRNA pattern yielded better separation of WT subtypes. A correlation analysis of the deregulated miRNA and mRNAs identified 13,026 miRNA/mRNA pairs with inversely correlated expression, of which 2844 are potential interactions of miRNA and their predicted mRNA targets. We found significant upregulation of miRNAs-183, -301a/b and -335 for the blastemal subtype, and miRNAs-181b, -223 and -630 for the regressive subtype. We found marked deregulation of miRNAs regulating epithelial to mesenchymal transition, especially in the blastemal subtype, and miRNAs influencing chemosensitivity, especially in regressive subtypes. Further research is needed to assess the influence of preoperative chemotherapy and tumor infiltrating lymphocytes on the miRNA and mRNA patterns in WT.

Oncogenic driver genes and the inflammatory microenvironment dictate liver tumor phenotype

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Matter, Matthias S; Marquardt, Jens U; Andersen, Jesper B

2016-01-01

The majority of hepatocellular carcinoma (HCC) develops in the background of chronic liver inflammation caused by viral hepatitis and alcoholic or non-alcoholic steatohepatitis. However, the impact of different types of chronic inflammatory microenvironments on the phenotypes of tumors generated...... with transcriptome profiles from human HCCs further demonstrated that AKT-CAT tumors generated in the context of chronic liver inflammation showed enrichment of poor prognosis gene sets or decrease of good prognosis gene sets. In contrast, DDC had a more subtle effect on AKT-NRAS(G12V) tumors and primarily enhanced...... by distinct oncogenes is largely unresolved. To address this issue, we generated murine liver tumors by constitutively active AKT-1 (AKT) and β-catenin (CAT) followed by induction of chronic liver inflammation by 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) and carbon tetrachloride (CCl4 ). Also...

Tumor heterogeneity is an active process maintained by a mutant EGFR-induced cytokine circuit in glioblastoma.

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Inda, Maria-del-Mar; Bonavia, Rudy; Mukasa, Akitake; Narita, Yoshitaka; Sah, Dinah W Y; Vandenberg, Scott; Brennan, Cameron; Johns, Terrance G; Bachoo, Robert; Hadwiger, Philipp; Tan, Pamela; Depinho, Ronald A; Cavenee, Webster; Furnari, Frank

2010-08-15

Human solid tumors frequently have pronounced heterogeneity of both neoplastic and normal cells on the histological, genetic, and gene expression levels. While current efforts are focused on understanding heterotypic interactions between tumor cells and surrounding normal cells, much less is known about the interactions between and among heterogeneous tumor cells within a neoplasm. In glioblastoma multiforme (GBM), epidermal growth factor receptor gene (EGFR) amplification and mutation (EGFRvIII/DeltaEGFR) are signature pathogenetic events that are invariably expressed in a heterogeneous manner. Strikingly, despite its greater biological activity than wild-type EGFR (wtEGFR), individual GBM tumors expressing both amplified receptors typically express wtEGFR in far greater abundance than the DeltaEGFR lesion. We hypothesized that the minor DeltaEGFR-expressing subpopulation enhances tumorigenicity of the entire tumor cell population, and thereby maintains heterogeneity of expression of the two receptor forms in different cells. Using mixtures of glioma cells as well as immortalized murine astrocytes, we demonstrate that a paracrine mechanism driven by DeltaEGFR is the primary means for recruiting wtEGFR-expressing cells into accelerated proliferation in vivo. We determined that human glioma tissues, glioma cell lines, glioma stem cells, and immortalized mouse Ink4a/Arf(-/-) astrocytes that express DeltaEGFR each also express IL-6 and/or leukemia inhibitory factor (LIF) cytokines. These cytokines activate gp130, which in turn activates wtEGFR in neighboring cells, leading to enhanced rates of tumor growth. Ablating IL-6, LIF, or gp130 uncouples this cellular cross-talk, and potently attenuates tumor growth enhancement. These findings support the view that a minor tumor cell population can potently drive accelerated growth of the entire tumor mass, and thereby actively maintain tumor cell heterogeneity within a tumor mass. Such interactions between genetically

Application of Adoptive T-Cell Therapy Using Tumor Antigen-Specific T-Cell Receptor Gene Transfer for the Treatment of Human Leukemia

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Toshiki Ochi

2010-01-01

Full Text Available The last decade has seen great strides in the field of cancer immunotherapy, especially the treatment of melanoma. Beginning with the identification of cancer antigens, followed by the clinical application of anti-cancer peptide vaccination, it has now been proven that adoptive T-cell therapy (ACT using cancer antigen-specific T cells is the most effective option. Despite the apparent clinical efficacy of ACT, the timely preparation of a sufficient number of cancer antigen-specific T cells for each patient has been recognized as its biggest limitation. Currently, therefore, attention is being focused on ACT with engineered T cells produced using cancer antigen-specific T-cell receptor (TCR gene transfer. With regard to human leukemia, ACT using engineered T cells bearing the leukemia antigen-specific TCR gene still remains in its infancy. However, several reports have provided preclinical data on TCR gene transfer using Wilms' tumor gene product 1 (WT1, and also preclinical and clinical data on TCR gene transfer involving minor histocompatibility antigen, both of which have been suggested to provide additional clinical benefit. In this review, we examine the current status of anti-leukemia ACT with engineered T cells carrying the leukemia antigen-specific TCR gene, and discuss the existing barriers to progress in this area.

P18 tumor suppressor gene and progression of oligodendrogliomas to anaplasia.

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He, J; Hoang-Xuan, K; Marie, Y; Leuraud, P; Mokhtari, K; Kujas, M; Delattre, J Y; Sanson, M

2000-09-26

P18INK4C is a good candidate to be the tumor suppressor gene involved in oligodendrogliomas on 1p32. Loss of heterozygosity on 1p, mutation(s), homozygous deletion(s), and expression of p18 in 30 oligodendroglial tumors were investigated. Loss of heterozygosity on 1p was found in 15 tumors. A p18 mutation was found at an recurrence of an anaplastic oligodendroglioma, but not in the primary, low-grade tumor. No homozygous deletions were found and p18 was expressed in all cases. These results show that p18 alteration is involved in tumor progression in a subset of oligodendrogliomas.

Alterations in the K-ras and p53 genes in rat lung tumors

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Belinsky, S.A.; Swafford, D.S.; Finch, G.L.; Mitchell, C.E. [Inhalation Toxicology Research Institute, Albuquerque, NM (United States)] [and others

1997-06-01

Activation of the K-ras protooncogene and inactivation of the p53 tumor suppressor gene are events common to many types of human cancers. Molecular epidemiology studies have associated mutational profiles in these genes with specific exposures. The purpose of this paper is to review investigations that have examined the role of the K-ras and p53 genes in lung tumors induced in the F344 rat by mutagenic and nonmutagenic exposures. Mutation profiles within the K-ras and p53 genes, if present in rat lung tumors, would help to define some of the molecular mechanisms underlying cancer induction by various environmental agents. Pulmonary adenocarcinomas or squamous cell carcinomas were induced by tetranitromethane (TNM), 4-methylnitrosamino-1-(3-pyridyl)-1-butanone (NNK), beryllium metal, plutonium-239, X-ray, diesel exhaust, or carbon black. These agents were chosen because the tumors they produced could arise via different types of DNA damage. Mutation of the K-ras gene was determined by approaches that included DNA transfection, direct sequencing, mismatch hybridization, and restriction fragment length polymorphism analysis. The frequency for mutation of the K-ras gene was exposure dependent. The transition mutations formed could have been derived from deamination of cytosine. Alteration in the p53 gene was assessed by immunohistochemical analysis for p53 protein and single-strand conformation polymorphism (SSCP) analysis of exons 4 to 9. None of the 93 adenocarinomas examined was immunoreactive toward the anti-p53 antibody CM1. In contrast, 14 of 71 squamous cell carcinomas exhibited nuclear p53 immunoreactivity with no correlation to type of exposure. However, SSCP analysis only detected mutations in 2 of 14 squamous cell tumors that were immunoreactive, suggesting that protein stabilization did not stem from mutations within the p53 gene. Thus, the p53 gene does not appear to be involved in the genesis of most rat lung tumors. 2 figs., 2 tabs., 48 refs.

Cancer tumors as Metazoa 1.0: tapping genes of ancient ancestors

International Nuclear Information System (INIS)

Davies, P C W; Lineweaver, C H

2011-01-01

The genes of cellular cooperation that evolved with multicellularity about a billion years ago are the same genes that malfunction to cause cancer. We hypothesize that cancer is an atavistic condition that occurs when genetic or epigenetic malfunction unlocks an ancient 'toolkit' of pre-existing adaptations, re-establishing the dominance of an earlier layer of genes that controlled loose-knit colonies of only partially differentiated cells, similar to tumors. The existence of such a toolkit implies that the progress of the neoplasm in the host organism differs distinctively from normal Darwinian evolution. Comparative genomics and the phylogeny of basal metazoans, opisthokonta and basal multicellular eukaryotes should help identify the relevant genes and yield the order in which they evolved. This order will be a rough guide to the reverse order in which cancer develops, as mutations disrupt the genes of cellular cooperation. Our proposal is consistent with current understanding of cancer and explains the paradoxical rapidity with which cancer acquires a suite of mutually-supportive complex abilities. Finally we make several predictions and suggest ways to test this model

Molecular Imaging of Gene Expression and Efficacy following Adenoviral-Mediated Brain Tumor Gene Therapy

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Alnawaz Rehemtulla

2002-01-01

Full Text Available Cancer gene therapy is an active area of research relying upon the transfer and subsequent expression of a therapeutic transgene into tumor cells in order to provide for therapeutic selectivity. Noninvasive assessment of therapeutic response and correlation of the location, magnitude, and duration of transgene expression in vivo would be particularly useful in the development of cancer gene therapy protocols by facilitating optimization of gene transfer protocols, vector development, and prodrug dosing schedules. In this study, we developed an adenoviral vector containing both the therapeutic transgene yeast cytosine deaminase (yCD along with an optical reporter gene (luciferase. Following intratumoral injection of the vector into orthotopic 9L gliomas, anatomical and diffusion-weighted MR images were obtained over time in order to provide for quantitative assessment of overall therapeutic efficacy and spatial heterogeneity of cell kill, respectively. In addition, bioluminescence images were acquired to assess the duration and magnitude of gene expression. MR images revealed significant reduction in tumor growth rates associated with yCD/5-fluorocytosine (5FC gene therapy. Significant increases in mean tumor diffusion values were also observed during treatment with 5FC. Moreover, spatial heterogeneity in tumor diffusion changes were also observed revealing that diffusion magnetic resonance imaging could detect regional therapeutic effects due to the nonuniform delivery and/or expression of the therapeutic yCD transgene within the tumor mass. In addition, in vivo bioluminescence imaging detected luciferase gene expression, which was found to decrease over time during administration of the prodrug providing a noninvasive surrogate marker for monitoring gene expression. These results demonstrate the efficacy of the yCD/5FC strategy for the treatment of brain tumors and reveal the feasibility of using multimodality molecular and functional imaging

Neurospora crassa glucose - repressible gene -1(Grg-1) promoter controls the expression of neurospora tyrosinase gene in a clock-controlled manner

International Nuclear Information System (INIS)

Tarawneh, A. K

1997-01-01

In this study sphareroplastes of white Neurospora crassa mutant auxotroph for aromatic am no acids a rom 9 q a-2 inv, was transformed by the pKF-Tyr7-wt DNA construct. This construct contains the promoter of neurospora crassa glucose-repressible gene-1 (G rg-1) usp stream of Neurospora tyrosinase gene. The co transformation of this mutant with pKF-Tyr-7-wt cincture's and the pKAL-1, a plasmid which contains the Neurospora q a-2+ gene transform it to photophor. The transform ant contains the tyrosinase gene which catalyzes the unique step in the synthesis of the black pigment melanin. The activity of the tyrosinase in this transform ant was followed by measuring the absorbance of the dark coloured pigment at 332 nm. The maximum of the tyrosinase activity was shown at 16.36 and 56 hours after the shift of the transformed mycelia from constant light (L L) to constant dark (Dd). The rate of the enzyme activity was changed according to ci radian cycle of 20 hours. This G rg 1/tyrosinase construct provides a good system to study to study the temporal control of gene expression and the interaction between the different environmental c uses that affects gene expression. (author). 20 refs., 4 figs

Cytokine Gene Polymorphisms in Egyptian Cases with Brain Tumors

International Nuclear Information System (INIS)

Badr El-Din, N.K.; Abdel-Hady, E.K.; Salem, F.K.; Settin, A.; ALI, N.

2009-01-01

Background: Cytokines are proposed to play important roles in brain tumor biology as well as neuro degeneration or impaired neuronal function. Objectives: This work aimed to check the association of polymorphisms of cytokine genes in Egyptian cases with brain tumors. Methods: This work included 45 cases affected by brain tumors diagnosed as 24 benign and 21 malignant. Their median age was 45 years, and they were 20 males and 25 females. These cases were taken randomly from the Neurosurgery Department of Mansoura University Hospital, Egypt. Case genotypes were compared to 98 healthy unrelated controls from the same locality. DNA was amplified using PCR utilizing sequence specific primers (SSP) for detection of polymorphisms related to TNF-a-308 (G/A), IL-10-1082 (G/A), IL-6-174 (G/C) and IL-1Ra (VNTR) genes. Results: Cases affected with benign brain tumors showed a significant higher frequency of IL-10-1082 A/A [odds ratio (OR=8.0), p<0.001] and IL-6-174 C/C (OR=6.3, p=0.002) homozygous genotypes as compared to controls. Malignant cases, on the other hand, showed significantly higher frequency of IL-6-174 C/C (OR =4.8, p=0.002) homozygous genotype and TNF-a-308 A/A (OR=4.9, p<0.001) homozygous genotype when compared to controls. In the meantime, all cases showed no significant difference regarding the distribution of IL-1Ra VNTR genotype polymorphism compared to controls. Conclusions: Cytokine gene polymorphisms showed a pattern of association with brain tumors which may have potential impact on family counseling and disease management.

¹¹¹In-DOTA-Annexin V for imaging of apoptosis during HSV1-tk/GCV prodrug activation gene therapy in mice with NG4TL4 sarcoma.

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Lin, Ming-Hsien; Wu, Shih-Yen; Wang, Hsin-Ell; Liu, Ren-Shyan; Chen, Jyh-Cheng

2016-02-01

Apoptosis has been suggested as a cytocidal mechanism of the HSV1-tk-expressing cells when exposed to ganciclovir (GCV). This study evaluated the efficacy of (111)In-labeled Annexin V for monitoring tumor responses during prodrug activation gene therapy with HSV1-tk and GCV. Annexin V was conjugated to DOTA using N-hydroxysulfosuccinimide (sulfo-NHS) and 1-ethyl-3-[3-(dimethylamino)propyl]carbodiimide (EDC), labeled with (111)In-InCl3 and purified using size exclusion chromatography to give (111)In-DOTA-Annexin V conjugate. The radiochemical yield and the radiochemical purity of (111)In-DOTA-Annexin V were 74±12% and 98±3%, respectively (n=10). (111)In-DOTA-BSA was prepared similarly. An in vitro study to demonstrate the apoptosis of NG4TL4-STK cells after GCV treatment has been performed. Mice bearing NG4TL4-STK and NG4TL4-WT tumors were treated with GCV (10 mg/kg daily) by i.p. injection for 7 consecutive days. Before and during the GCV treatment, biodistribution studies and scintigraphic imaging were performed at 2h post injection of the radiotracers. The uptake of (111)In-DOTA-Annexin V in treated cells (13.41±1.30%) was 4.1 times higher than that in untreated cells (3.21±0.37%). The GCV-induced cell apoptosis in NG4TL4-STK tumor resulted in a significantly increasing accumulation of (111)In-DOTA-Annexin V (1.92±0.32%ID/g at day 0, 4.79±0.86%ID/g at day 2, 4.56±0.58%ID/g at day 4) was observed, but not for that of (111)In-DOTA-BSA. During consecutive GCV treatment, scintigraphic imaging with (111)In-DOTA-Annexin V revealed high uptake in NG4TL4-STK tumor compared with that in NG4TL4-WT tumor. However, no specific (111)In-DOTA-BSA accumulation in NG4TL4-STK and NG4TL4-WT tumors was observed throughout the course of GCV treatment. This study demonstrated that (111)In-DOTA-Annexin V can be used for monitoring tumor cell apoptosis during prodrug activation gene therapy with HSV1-tk and GCV for cancer treatment. Copyright © 2015 Elsevier Ltd. All rights

Genes that cooperate with tumor promoters in transformation

International Nuclear Information System (INIS)

Colburn, N.H.; Smith, B.M.

1988-01-01

Tumor-promoting phorbol esters, like growth factors, elicit pleiotropic responses involving biochemical pathways that lead to different biological responses. Genetic variant cell lines that are resistant to mitogenic, differentiation, or transformation responses to tumor promoters have been valuable tools for understanding the molecular bases of these responses. Studies using the mouse epidermal JB6 cell lines that are sensitive or resistant to tumor promoter-induced transformation have yielded new understanding of genetic and signal transduction events involved in neoplastic transformation. The isolation and characterization of cloned mouse promotion sensitivity genes pro-1 and pro-2 is reviewed. A new activity of pro-1 has been identified: when transfected into human cancer prone basal cell nevus syndrome fibroblasts but not normal fibroblasts mouse pro-1 confers lifespan extension of these cells. Recently, we have found tat a pro-1 homolog from a library of nasopharyngeal carcinoma, but not the homolog from a normal human library, is activated for transferring promotion sensitivity. The many genetic variants for responses to tumor promoters have also proved valuable for signal transduction studies. JPB P- cells fail to show the 12-O-tetradecanoyl-phorbol-13-acetate (TPA)-induced syntheses of two proteins of 15 and 16 kD seen in P+ cells. P-, P+, and TPA transformed cells show a progressive decrease in both basal and TPA-inducible levels of a protein kinase C substrate of 80 kD. P- cells are relatively resistant both to anchorage-independent transformation and to a protein band shift induced by the calcium analog lanthanum. It appears that one or more calcium-binding proteins and one or more pro genes may be critical determinants of tumor promoter-induced neoplastic transformation

A Biphasic Pleural Tumor with Features of an Epithelioid and Small Cell Mesothelioma: Morphologic and Molecular Findings

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Sarah Hackman

2016-01-01

Full Text Available Malignant mesotheliomas are generally classified into epithelioid, sarcomatoid, desmoplastic, and biphasic types with rare reports of a small cell form. These small cell variants display some morphologic overlap with desmoplastic small round cell tumors (DSRCTs which generally occur within the abdominal cavity of young males and are defined by a characteristic t(11;22(p13;q12 translocation. However, there are rare reports of DSRCTs lacking this translocation. We present a 78-year-old man with a pleura-based biphasic neoplasm with features of both epithelioid mesothelioma and a small cell blastema-like neoplasm. The epithelioid portion showed IHC reactivity for pan cytokeratin, CK5/6, D2-40, and calretinin and the small cell portion marked with CD99, pan cytokeratin, WT1, FLI1, S100, CD200, MyoD1, and CD15. Fluorescence in situ hybridization testing for the t(11;22(p13;q12 translocation disclosed loss of the EWSR1 gene in 94% of tumor cell nuclei, but there was no evidence of the classic translocation. Array based-comparative genomic hybridization (a-CGH confirmed the tumor had numerous chromosome copy number losses, including 11p15.5-p11.12 and 22q12.1-q13.33, with loss of the EWSR1 and WT1 gene regions. Herein, we report novel complex CGH findings in a biphasic tumor and review the molecular genetic alterations in both mesothelioma and DSRCTs.

Novel fusion genes and chimeric transcripts in ependymal tumors

DEFF Research Database (Denmark)

Olsen, Thale Kristin; Panagopoulos, Ioannis; Gorunova, Ludmila

2016-01-01

with subsequent Sanger sequencing was used to validate the potential fusions. Fluorescent in situ hybridization (FISH) using locus-specific probes was also performed. A total of 841 candidate chimeric transcripts were identified in the 12 tumors, with an average of 49 unique candidate fusions per tumor. After...... infratentorial anaplastic ependymoma. Our previously reported ALK rearrangements and the RELA and YAP1 fusions found in supratentorial ependymomas were until now the only known fusion genes present in ependymal tumors. The chimeric transcripts presented here are the first to be reported in infratentorial...

Gene Expression of Glucose Transporter 1 (GLUT1, Hexokinase 1 and Hexokinase 2 in Gastroenteropancreatic Neuroendocrine Tumors: Correlation with F-18-fluorodeoxyglucose Positron Emission Tomography and Cellular Proliferation

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Andreas Kjaer

2013-10-01

Full Text Available Neoplastic tissue exhibits high glucose utilization and over-expression of glucose transporters (GLUTs and hexokinases (HKs, which can be imaged by 18F-Fluorodeoxyglucose-positron emission tomography (FDG-PET. The aim of the present study was to investigate the expression of glycolysis-associated genes and to compare this with FDG-PET imaging as well as with the cellular proliferation index in two cancer entities with different malignant potential. Using real-time PCR, gene expression of GLUT1, HK1 and HK2 were studied in 34 neuroendocrine tumors (NETs in comparison with 14 colorectal adenocarcinomas (CRAs. The Ki67 proliferation index and, when available, FDG-PET imaging was compared with gene expression. Overexpression of GLUT1 gene expression was less frequent in NETs (38% compared to CRAs (86%, P = 0.004. HK1 was overexpressed in 41% and 71% of NETs and CRAs, respectively (P = 0.111 and HK2 was overexpressed in 50% and 64% of NETs and CRAs, respectively (P = 0.53. There was a significant correlation between the Ki67 proliferation index and GLUT1 gene expression for the NETs (R = 0.34, P = 0.047, but no correlation with the hexokinases. FDG-PET identified foci in significantly fewer NETs (36% than CRAs (86%, (P = 0.04. The gene expression results, with less frequent GLUT1 and HK1 upregulation in NETs, confirmed the lower metabolic activity of NETs compared to the more aggressive CRAs. In accordance with this, fewer NETs were FDG-PET positive compared to CRA tumors and FDG uptake correlated with GLUT1 gene expression.

The pituitary tumor transforming gene 1 (PTTG-1: An immunological target for multiple myeloma

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Gagliano Nicoletta

2008-04-01

Full Text Available Abstract Background Multiple Myeloma is a cancer of B plasma cells, which produce non-specific antibodies and proliferate uncontrolled. Due to the potential relapse and non-specificity of current treatments, immunotherapy promises to be more specific and may induce long-term immunity in patients. The pituitary tumor transforming gene 1 (PTTG-1 has been shown to be a novel oncogene, expressed in the testis, thymus, colon, lung and placenta (undetectable in most other tissues. Furthermore, it is over expressed in many tumors such as the pituitary adenoma, breast, gastrointestinal cancers, leukemia, lymphoma, and lung cancer and it seems to be associated with tumorigenesis, angiogenesis and cancer progression. The purpose was to investigate the presence/rate of expression of PTTG-1 in multiple myeloma patients. Methods We analyzed the PTTG-1 expression at the transcriptional and the protein level, by PCR, immunocytochemical methods, Dot-blot and ELISA performed on patient's sera in 19 multiple myeloma patients, 6 different multiple myeloma cell lines and in normal human tissue. Results We did not find PTTG-1 presence in the normal human tissue panel, but PTTG-1 mRNA was detectable in 12 of the 19 patients, giving evidence of a 63% rate of expression (data confirmed by ELISA. Four of the 6 investigated cell lines (66.6% were positive for PTTG-1. Investigations of protein expression gave evidence of 26.3% cytoplasmic expression and 16% surface expression in the plasma cells of multiple myeloma patients. Protein presence was also confirmed by Dot-blot in both cell lines and patients. Conclusion We established PTTG-1's presence at both the transcriptional and protein levels. These data suggest that PTTG-1 is aberrantly expressed in multiple myeloma plasma cells, is highly immunogenic and is a suitable target for immunotherapy of multiple myeloma.

Tumor suppressor genes that escape from X-inactivation contribute to cancer sex bias

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Dunford, Andrew; Weinstock, David M.; Savova, Virginia; Schumacher, Steven E.; Cleary, John P.; Yoda, Akinori; Sullivan, Timothy J.; Hess, Julian M.; Gimelbrant, Alexander A.; Beroukhim, Rameen; Lawrence, Michael S.; Getz, Gad; Lane, Andrew A.

2016-01-01

There is a striking and unexplained male predominance across many cancer types. A subset of X chromosome (chrX) genes can escape X-inactivation, which would protect females from complete functional loss by a single mutation. To identify putative “Escape from X-Inactivation Tumor Suppressor” (EXITS) genes, we compared somatic alterations from >4100 cancers across 21 tumor types for sex bias. Six of 783 non-pseudoautosomal region (PAR) chrX genes (ATRX, CNKSR2, DDX3X, KDM5C, KDM6A, and MAGEC3) more frequently harbored loss-of-function mutations in males (based on false discovery rate <0.1), compared to zero of 18,055 autosomal and PAR genes (P<0.0001). Male-biased mutations in genes that escape X-inactivation were observed in combined analysis across many cancers and in several individual tumor types, suggesting a generalized phenomenon. We conclude that biallelic expression of EXITS genes in females explains a portion of the reduced cancer incidence compared to males across a variety of tumor types. PMID:27869828

Tumor-suppressor genes that escape from X-inactivation contribute to cancer sex bias.

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Dunford, Andrew; Weinstock, David M; Savova, Virginia; Schumacher, Steven E; Cleary, John P; Yoda, Akinori; Sullivan, Timothy J; Hess, Julian M; Gimelbrant, Alexander A; Beroukhim, Rameen; Lawrence, Michael S; Getz, Gad; Lane, Andrew A

2017-01-01

There is a striking and unexplained male predominance across many cancer types. A subset of X-chromosome genes can escape X-inactivation, which would protect females from complete functional loss by a single mutation. To identify putative 'escape from X-inactivation tumor-suppressor' (EXITS) genes, we examined somatic alterations from >4,100 cancers across 21 tumor types for sex bias. Six of 783 non-pseudoautosomal region (PAR) X-chromosome genes (ATRX, CNKSR2, DDX3X, KDM5C, KDM6A, and MAGEC3) harbored loss-of-function mutations more frequently in males (based on a false discovery rate < 0.1), in comparison to zero of 18,055 autosomal and PAR genes (Fisher's exact P < 0.0001). Male-biased mutations in genes that escape X-inactivation were observed in combined analysis across many cancers and in several individual tumor types, suggesting a generalized phenomenon. We conclude that biallelic expression of EXITS genes in females explains a portion of the reduced cancer incidence in females as compared to males across a variety of tumor types.

The von Hippel-Lindau tumor suppressor gene inhibits hepatocyte growth factor/scatter factor-induced invasion and branching morphogenesis in renal carcinoma cells.

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Koochekpour, S; Jeffers, M; Wang, P H; Gong, C; Taylor, G A; Roessler, L M; Stearman, R; Vasselli, J R; Stetler-Stevenson, W G; Kaelin, W G; Linehan, W M; Klausner, R D; Gnarra, J R; Vande Woude, G F

1999-09-01

Loss of function in the von Hippel-Lindau (VHL) tumor suppressor gene occurs in familial and most sporadic renal cell carcinomas (RCCs). VHL has been linked to the regulation of cell cycle cessation (G(0)) and to control of expression of various mRNAs such as for vascular endothelial growth factor. RCC cells express the Met receptor tyrosine kinase, and Met mediates invasion and branching morphogenesis in many cell types in response to hepatocyte growth factor/scatter factor (HGF/SF). We examined the HGF/SF responsiveness of RCC cells containing endogenous mutated (mut) forms of the VHL protein (VHL-negative RCC) with that of isogenic cells expressing exogenous wild-type (wt) VHL (VHL-positive RCC). We found that VHL-negative 786-0 and UOK-101 RCC cells were highly invasive through growth factor-reduced (GFR) Matrigel-coated filters and exhibited an extensive branching morphogenesis phenotype in response to HGF/SF in the three-dimensional (3D) GFR Matrigel cultures. In contrast, the phenotypes of A498 VHL-negative RCC cells were weaker, and isogenic RCC cells ectopically expressing wt VHL did not respond at all. We found that all VHL-negative RCC cells expressed reduced levels of tissue inhibitor of metalloproteinase 2 (TIMP-2) relative to the wt VHL-positive cells, implicating VHL in the regulation of this molecule. However, consistent with the more invasive phenotype of the 786-0 and UOK-101 VHL-negative RCC cells, the levels of TIMP-1 and TIMP-2 were reduced and levels of the matrix metalloproteinases 2 and 9 were elevated compared to the noninvasive VHL-positive RCC cells. Moreover, recombinant TIMPs completely blocked HGF/SF-mediated branching morphogenesis, while neutralizing antibodies to the TIMPs stimulated HGF/SF-mediated invasion in vitro. Thus, the loss of the VHL tumor suppressor gene is central to changes that control tissue invasiveness, and a more invasive phenotype requires additional genetic changes seen in some but not all RCC lines. These

Clinical Utility of promoter methylation of the tumor suppressor genes DKK3, and RASSF1A in breast cancer patients

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Marwa H. Saied

2018-04-01

Full Text Available Background: DNA methylation is the commonest known epigenetic change that results in silencing of tumor suppressor genes. Promoter methylation of tumor suppressor genes has the potential for early detection of breast cancer. Aim: Aim is to examine the potential usefulness of blood based methylation specific polymerase chain reaction (MSP of methylated DKK3 and RASSF1A genes in early detection of breast cancer. Method: Methylation status of DKK3 and RASSF1 was investigated in forty breast cancer patients, twenty fibroadenoma patients and twenty healthy ladies as control group using MSP. Results: Methylation of DKK3 promoter was found in 22.5% of breast cancer patients, while DKK3 methylation was absent in both fibroadenoma patients and control group. Similarly, methylation of RASSF1 promoter was found in 17.5% of breast cancer patients and in none of fibroadenoma and control group. Conclusion: Promoter methylation of DKK3 and RASSF1 was found in breast cancer patients while absent in control group suggesting that tumorspecific methylation of the two genes (DKK3 and RASSF1A might be a valuable biomarker for the early detection of breast cancer. Keywords: DNA methylation, Breast cancer, DKK3, RASSF1

A Catalog of Genes Homozygously Deleted in Human Lung Cancer and the Candidacy of PTPRD as a Tumor Suppressor Gene

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Kohno, Takashi; Otsuka, Ayaka; Girard, Luc; Sato, Masanori; Iwakawa, Reika; Ogiwara, Hideaki; Sanchez-Cespedes, Montse; Minna, John D.; Yokota, Jun

2010-01-01

A total of 176 genes homozygously deleted in human lung cancer were identified by DNA array-based whole genome scanning of 52 lung cancer cell lines and subsequent genomic PCR in 74 cell lines, including the 52 cell lines scanned. One or more exons of these genes were homozygously deleted in one (1%) to 20 (27%) cell lines. These genes included known tumor suppressor genes, e.g., CDKN2A/p16, RB1, and SMAD4, and candidate tumor suppressor genes whose hemizygous or homozygous deletions were reported in several types of human cancers, such as FHIT, KEAP1, and LRP1B/LRP-DIP. CDKN2A/p16 and p14ARF located in 9p21 were most frequently deleted (20/74, 27%). The PTPRD gene was most frequently deleted (8/74, 11%) among genes mapping to regions other than 9p21. Somatic mutations, including a nonsense mutation, of the PTPRD gene were detected in 8/74 (11%) of cell lines and 4/95 (4%) of surgical specimens of lung cancer. Reduced PTPRD expression was observed in the majority (>80%) of cell lines and surgical specimens of lung cancer. Therefore, PTPRD is a candidate tumor suppressor gene in lung cancer. Microarray-based expression profiling of 19 lung cancer cell lines also indicated that some of the 176 genes, such as KANK and ADAMTS1, are preferentially inactivated by epigenetic alterations. Genetic/epigenetic as well as functional studies of these 176 genes will increase our understanding of molecular mechanisms behind lung carcinogenesis. PMID:20073072

Quantitative Methylation Profiles for Multiple Tumor Suppressor Gene Promoters in Salivary Gland Tumors

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Durr, Megan L.; Mydlarz, Wojciech K.; Shao, Chunbo; Zahurak, Marianna L.; Chuang, Alice Y.; Hoque, Mohammad O.; Westra, William H.; Liegeois, Nanette J.; Califano, Joseph A.; Sidransky, David; Ha, Patrick K.

2010-01-01

Background Methylation profiling of tumor suppressor gene (TSGs) promoters is quickly becoming a powerful diagnostic tool for the early detection, prognosis, and even prediction of clinical response to treatment. Few studies address this in salivary gland tumors (SGTs); hence the promoter methylation profile of various TSGs was quantitatively assessed in primary SGT tissue to determine if tumor-specific alterations could be detected. Methodology DNA isolated from 78 tumor and 17 normal parotid gland specimens was assayed for promoter methylation status of 19 TSGs by fluorescence-based, quantitative methylation-specific PCR (qMSP). The data were utilized in a binary fashion as well as quantitatively (using a methylation quotient) allowing for better profiling and interpretation of results. Principal Findings The average number of methylation events across the studied genes was highest in salivary duct carcinoma (SDC), with a methylation value of 9.6, compared to the normal 4.5 (ptrend for increasing methylation in APC, Mint 1, PGP9.5, RAR-β, and Timp3. Conclusions/Significance Screening promoter methylation profiles in SGTs showed considerable heterogeneity. The methylation status of certain markers was surprisingly high in even normal salivary tissue, confirming the need for such controls. Several TSGs were found to be associated with malignant SGTs, especially SDC. Further study is needed to evaluate the potential use of these associations in the detection, prognosis, and therapeutic outcome of these rare tumors. PMID:20520817

Partial least squares based gene expression analysis in estrogen receptor positive and negative breast tumors.

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Ma, W; Zhang, T-F; Lu, P; Lu, S H

2014-01-01

Breast cancer is categorized into two broad groups: estrogen receptor positive (ER+) and ER negative (ER-) groups. Previous study proposed that under trastuzumab-based neoadjuvant chemotherapy, tumor initiating cell (TIC) featured ER- tumors response better than ER+ tumors. Exploration of the molecular difference of these two groups may help developing new therapeutic strategies, especially for ER- patients. With gene expression profile from the Gene Expression Omnibus (GEO) database, we performed partial least squares (PLS) based analysis, which is more sensitive than common variance/regression analysis. We acquired 512 differentially expressed genes. Four pathways were found to be enriched with differentially expressed genes, involving immune system, metabolism and genetic information processing process. Network analysis identified five hub genes with degrees higher than 10, including APP, ESR1, SMAD3, HDAC2, and PRKAA1. Our findings provide new understanding for the molecular difference between TIC featured ER- and ER+ breast tumors with the hope offer supports for therapeutic studies.

Wilms' Tumor 1 Overexpression in Granulosa Cells Is Associated with Polycystic Ovaries in Polycystic Ovary Syndrome Patients.

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Wang, Qun; Huang, Tao; Shu, Xin; Zhao, Shi-Gang; Liang, Yu; Muhammad, Tahir; Gao, Fei; Zhao, Han; Liu, Hong-Bin

2018-01-01

Polycystic ovary syndrome (PCOS) is a heterogeneous disorder characterized by chronic ovulatory dysfunction, hyperandrogenism, and polycystic ovaries. Wilms' tumor 1 (WT1) encoding a transcription factor involved in the differentiation of granulosa cells (GCs) regulates androgen receptor in the development of male genitalia. However, the expression pattern and possible role of WT1 in ovaries of PCOS patients are still unknown. GCs from 95 PCOS patients (PCOS group) and 62 healthy controls (control group) were isolated. The expression of WT1 in GCs was quantified using the reverse transcription-polymerase chain reaction. The correlation between WT1 expression and clinical characteristics was evaluated in PCOS patients. WT1 expression was increased in PCOS patients compared with the normal controls. The expression of WT1 was moderately correlated with testosterone (r = 0.334, p = 0.001) and luteinizing hormone (r = 0.357, p = 0.001) levels and the antral follicle counts (r = 0.337, p = 0.001). Our study provided novel insights into the relationship between hyperandrogenism and polycystic ovaries of PCOS and WT1. © 2018 S. Karger AG, Basel.

Epithelial-stromal interaction 1 (EPSTI1) substitutes for peritumoral fibroblasts in the tumor microenvironment

DEFF Research Database (Denmark)

De Neergaard, Michala; Kim, Jiyoung; Villadsen, René

2010-01-01

Tumor cells can activate stroma, yet the implication of this activation in terms of reciprocal induction of gene expression in tumor cells is poorly understood. Epithelial Stromal Interaction 1 (EPSTI1) is an interferon response gene originally isolated from heterotypic recombinant cultures...... of human breast cancer cells and activated breast myofibroblasts. Here we describe the first immunolocalization of EPSTI1 in normal and cancerous breast tissue, and we provide evidence for a role of this molecule in the regulation of tumor cell properties and epithelial-mesenchymal transition. In general...... cell line and silenced endogenous EPSTI1 by RNA interference in another. Irrespective of the experimental approach, EPSTI1 expression led to an increase in tumorsphere formation-a property associated with breast stem/progenitor cells. Most remarkably, we show that EPSTI1, by conveying spread of tumor...

Quantitative promoter methylation analysis of multiple cancer-related genes in renal cell tumors

International Nuclear Information System (INIS)

Costa, Vera L; Henrique, Rui; Ribeiro, Franclim R; Pinto, Mafalda; Oliveira, Jorge; Lobo, Francisco; Teixeira, Manuel R; Jerónimo, Carmen

2007-01-01

Aberrant promoter hypermethylation of cancer-associated genes occurs frequently during carcinogenesis and may serve as a cancer biomarker. In this study we aimed at defining a quantitative gene promoter methylation panel that might identify the most prevalent types of renal cell tumors. A panel of 18 gene promoters was assessed by quantitative methylation-specific PCR (QMSP) in 85 primarily resected renal tumors representing the four major histologic subtypes (52 clear cell (ccRCC), 13 papillary (pRCC), 10 chromophobe (chRCC), and 10 oncocytomas) and 62 paired normal tissue samples. After genomic DNA isolation and sodium bisulfite modification, methylation levels were determined and correlated with standard clinicopathological parameters. Significant differences in methylation levels among the four subtypes of renal tumors were found for CDH1 (p = 0.0007), PTGS2 (p = 0.002), and RASSF1A (p = 0.0001). CDH1 hypermethylation levels were significantly higher in ccRCC compared to chRCC and oncocytoma (p = 0.00016 and p = 0.0034, respectively), whereas PTGS2 methylation levels were significantly higher in ccRCC compared to pRCC (p = 0.004). RASSF1A methylation levels were significantly higher in pRCC than in normal tissue (p = 0.035). In pRCC, CDH1 and RASSF1A methylation levels were inversely correlated with tumor stage (p = 0.031) and nuclear grade (p = 0.022), respectively. The major subtypes of renal epithelial neoplasms display differential aberrant CDH1, PTGS2, and RASSF1A promoter methylation levels. This gene panel might contribute to a more accurate discrimination among common renal tumors, improving preoperative assessment and therapeutic decision-making in patients harboring suspicious renal masses

Tumoral Environment Triggers Transcript Anomalies in Established Tumors: Induction of Altered Gene Expression and of Aberrant, Truncated and B2 Repeat-Containing Gene Transcripts

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Pieter Rottiers

1999-12-01

Full Text Available In addition to eugenetic changes, cancerous cells exhibit extensive modifications in the expression levels of a variety of genes. The phenotypic switch observed after inoculation of T lymphoma cells into syngenic mice illustrates the active participation of tumoral environment in the induction of an aberrant gene expression pattern. To further substantiate this contribution, we performed polymerase chain reaction (PCR-based subtraction suppression hybridization (SSH to identify genes that are differentially expressed in tumor-derived EL4/13.3 cells compared to the same cells isolated from cultures. Besides a number of unknown genes, the subtracted library contained several known genes that have been reported to be expressed at increased levels in tumors and/or to contribute to carcinogenesis. Apart from clones representing translated transcripts, the subtracted library also contained a high number of clones representing B2 repeat elements, viz. short interspersed repetitive elements that are transcribed by RNA polymerase III. Northern blotting confirmed the induction of B2 transcripts in tumor tissue and also revealed induction of chimeric, B2 repeat-containing mRNA. The appearance of chimeric transcripts was accompanied by aberrant, shorter-than-full-length transcripts, specifically from upregulated genes. Accordingly, in addition to altered gene expression, tumoral environmental triggers constitute a potent mechanism to create an epigenetic diversity in cancers by inducing extensive transcript anomalies.

Comparison of ESR1 Mutations in Tumor Tissue and Matched Plasma Samples from Metastatic Breast Cancer Patients

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Takashi Takeshita

2017-10-01

Full Text Available BACKGROUND: ESR1 mutation in circulating cell-free DNA (cfDNA is emerging as a noninvasive biomarker of acquired resistance to endocrine therapy, but there is a paucity of data comparing the status of ESR1 gene in cfDNA with that in its corresponding tumor tissue. The objective of this study is to validate the degree of concordance of ESR1 mutations between plasma and tumor tissue. METHODS: ESR1 ligand-binding domain mutations Y537S, Y537N, Y537C, and D538G were analyzed using droplet digital PCR in 35 patients with metastatic breast cancer (MBC (35 tumor tissue samples and 67 plasma samples. RESULTS: Of the 35 paired samples, 26 (74.3% were concordant: one patient had detectable ESR1 mutations both plasma (ESR1 Y537S/Y537N and tumor tissue (ESR1 Y537S/Y537C, and 25 had WT ESR1 alleles in both. Nine (25.7% had discordance between the plasma and tissue results: five had mutations detected only in their tumor tissue (two Y537S, one Y537C, one D538G, and one Y537S/Y537N/D538G, and four had mutations detected only in their plasma (one Y537S, one Y537N, and two Y537S/Y537N/D538G. Furthermore, longitudinal plasma samples from 19 patients were used to assess changes in the presence of ESR1 mutations during treatment. Eleven patients had cfDNA ESR1 mutations over the course of treatment. A total of eight of 11 patients with MBC with cfDNA ESR1 mutations (72.7% had the polyclonal mutations. CONCLUSION: We have shown the independent distribution of ESR1 mutations between plasma and tumor tissue in 35 patients with MBC.

Effect of homeopathic treatment on gene expression in Copenhagen rat tumor tissues.

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Thangapazham, Rajesh L; Rajeshkumar, N V; Sharma, Anuj; Warren, Jim; Singh, Anoop K; Ives, John A; Gaddipati, Jaya P; Maheshwari, Radha K; Jonas, Wayne B

2006-12-01

Increasing evidence suggests that the inability to undergo apoptosis is an important factor in the development and progression of prostate cancer. Agents that induce apoptosis may inhibit tumor growth and provide therapeutic benefit. In a recent study, the authors found that certain homeopathic treatments produced anticancer effects in an animal model. In this study, the authors examined the immunomodulating and apoptotic effects of these remedies. The authors investigated the effect of a homeopathic treatment regimen containing Conium maculatum, Sabal serrulata, Thuja occidentalis, and a MAT-LyLu Carcinosin nosode on the expression of cytokines and genes that regulate apoptosis. This was assessed in prostate cancer tissues, extracted from animals responsive to these drugs, using ribonuclease protection assay or reverse transcription polymerase chain reaction. There were no significant changes in mRNA levels of the apoptotic genes bax, bcl-2, bcl-x, caspase-1, caspase-2, caspase-3, Fas, FasL, or the cytokines interleukin (IL)-1alpha, IL-1beta, tumor necrosis factor (TNF)-beta, IL-3, IL-4, IL-5, IL-6, IL-10, TNF-alpha, IL-2, and interferon-gamma in prostate tumor and lung metastasis after treatment with homeopathic medicines. This study indicates that treatment with the highly diluted homeopathic remedies does not alter the gene expression in primary prostate tumors or in lung metastasis. The therapeutic effect of homeopathic treatments observed in the in vivo experiments cannot be explained by mechanisms based on distinct alterations in gene expression related to apoptosis or cytokines. Future research should explore subtle modulations in the expression of multiple genes in different biological pathways.

Cloning of the rat Waf1/Cip1 gene

International Nuclear Information System (INIS)

Belinsky, S.A.; Middleton, S.K.

1994-01-01

The progression of eukaryotic cells through the cell cycle involves the sequential expression of specific genes. This process is regulated by both external and internal stimuli that prevent the cell from prematurely entering the next phase before all macromolecular events have been completed. The activation and subsequent inactivation of cyclin dependent kinases (Cdks) represent one internal stimuli required to regulate the transit of cells from one stage of the cell cycle to the next. Another member of this regulatory cascade is the p53 tumor suppressor gene, which controls a G 1 checkpoint at which the cell cycle can be arrested prior to the initiation of DNA synthesis. Following DNA damage, p53 protein levels rise, and entry into S phase is delayed, presumably to allow time for repair of the lesions. When p53 function is lost, cells containing damaged DNA template enter S phase leading to fixation and propagation of genetic alterations. Recently, evidence linking the growth-suppressing activity of p53 and inactivation of Cdks has been provided by the cloning of the Waf1/Cip1 gene. Waf1/Cip1 encodes a protein of M r 21,000 (p21), which inhibits Cdks in vitro. The overexpression of Waf1/Cip1 in cells inhibits cell growth, suggesting that p21 is a downstream mediator of p53 function. Loss of Waf1/Cip1 gene function could lead to deregulation of the cell cycle and contribute to the development of the neoplastic phenotype in tumors that do not contain mutations in the p53 gene. The purpose of the present investigation was to clone the rat Waf1/Cip1 gene,then determine the frequency for alteration of this gene in lung tumors induced by X-rays

Proto-oncogene FBI-1 (Pokemon/ZBTB7A) Represses Transcription of the Tumor Suppressor Rb Gene via Binding Competition with Sp1 and Recruitment of Co-repressors*S⃞

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Jeon, Bu-Nam; Yoo, Jung-Yoon; Choi, Won-Il; Lee, Choong-Eun; Yoon, Ho-Geun; Hur, Man-Wook

2008-01-01

FBI-1 (also called Pokemon/ZBTB7A) is a BTB/POZ-domain Krüppel-like zinc-finger transcription factor. Recently, FBI-1 was characterized as a proto-oncogenic protein, which represses tumor suppressor ARF gene transcription. The expression of FBI-1 is increased in many cancer tissues. We found that FBI-1 potently represses transcription of the Rb gene, a tumor suppressor gene important in cell cycle arrest. FBI-1 binds to four GC-rich promoter elements (FREs) located at bp –308 to –188 of the Rb promoter region. The Rb promoter also contains two Sp1 binding sites: GC-box 1 (bp –65 to –56) and GC-box 2 (bp –18 to –9), the latter of which is also bound by FBI-1. We found that FRE3 (bp –244 to –236) is also a Sp1 binding element. FBI-1 represses transcription of the Rb gene not only by binding to the FREs, but also by competing with Sp1 at the GC-box 2 and the FRE3. By binding to the FREs and/or the GC-box, FBI-1 represses transcription of the Rb gene through its POZ-domain, which recruits a co-repressor-histone deacetylase complex and deacetylates histones H3 and H4 at the Rb gene promoter. FBI-1 inhibits C2C12 myoblast cell differentiation by repressing Rb gene expression. PMID:18801742

Differential Gene Expression in Primary Breast Tumors Associated with Lymph Node Metastasis

International Nuclear Information System (INIS)

Ellsworth, R.E.; Field, L.A.; Kane, J.L.; Love, B.; Hooke, J.A.; Shriver, C.D.

2011-01-01

Lymph node status remains one of the most useful prognostic indicators in breast cancer; however, current methods to assess nodal status disrupt the lymphatic system and may lead to secondary complications. Identification of molecular signatures discriminating lymph node-positive from lymph node-negative primary tumors would allow for stratification of patients requiring surgical assesment of lymph nodes. Primary breast tumors from women with negative (n=41) and positive (n=35) lymph node status matched for possible confounding factors were subjected to laser micro dissection and gene expression data generated. Although ANOVA analysis (P 1.5) revealed 13 differentially expressed genes, hierarchical clustering classified 90% of node-negative but only 66% of node-positive tumors correctly. The inability to derive molecular profiles of metastasis in primary tumors may reflect tumor heterogeneity, paucity of cells within the primary tumor with metastatic potential, influence of the microenvironment, or inherited host susceptibility to metastasis

Differential Gene Expression in Primary Breast Tumors Associated with Lymph Node Metastasis

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Ellsworth, Rachel E.; Field, Lori A.; Love, Brad; Kane, Jennifer L.; Hooke, Jeffrey A.; Shriver, Craig D.

2011-01-01

Lymph node status remains one of the most useful prognostic indicators in breast cancer; however, current methods to assess nodal status disrupt the lymphatic system and may lead to secondary complications. Identification of molecular signatures discriminating lymph node-positive from lymph node-negative primary tumors would allow for stratification of patients requiring surgical assesment of lymph nodes. Primary breast tumors from women with negative (n = 41) and positive (n = 35) lymph node status matched for possible confounding factors were subjected to laser microdissection and gene expression data generated. Although ANOVA analysis (P 1.5) revealed 13 differentially expressed genes, hierarchical clustering classified 90% of node-negative but only 66% of node-positive tumors correctly. The inability to derive molecular profiles of metastasis in primary tumors may reflect tumor heterogeneity, paucity of cells within the primary tumor with metastatic potential, influence of the microenvironment, or inherited host susceptibility to metastasis. PMID:22295210

Differential Gene Expression in Primary Breast Tumors Associated with Lymph Node Metastasis

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Rachel E. Ellsworth

2011-01-01

Full Text Available Lymph node status remains one of the most useful prognostic indicators in breast cancer; however, current methods to assess nodal status disrupt the lymphatic system and may lead to secondary complications. Identification of molecular signatures discriminating lymph node-positive from lymph node-negative primary tumors would allow for stratification of patients requiring surgical assesment of lymph nodes. Primary breast tumors from women with negative (=41 and positive (=35 lymph node status matched for possible confounding factors were subjected to laser microdissection and gene expression data generated. Although ANOVA analysis (1.5 revealed 13 differentially expressed genes, hierarchical clustering classified 90% of node-negative but only 66% of node-positive tumors correctly. The inability to derive molecular profiles of metastasis in primary tumors may reflect tumor heterogeneity, paucity of cells within the primary tumor with metastatic potential, influence of the microenvironment, or inherited host susceptibility to metastasis.

In vivo comparison of IVDU and IVFRU in HSV1-TK gene expressing tumor bearing rats

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Choi, T.H.Tae Hyun; Ahn, S.H.Soon Hyuk; Kwon, H.-C.Hee-Chung; Choi, C.W.Chang Woon; Awh, O.D.Ok Doo; Lim, S.M.Sang Moo. E-mail: smlim328@kcch.re.kr

2004-01-01

(E)-5-(2-Iodovinyl)-2'-deoxyuridine (IVDU) and (E)-5-(2-iodovinyl)-2'-fluoro-2'-deoxyuridine (IVFRU) are potential substrates of Herpes Simplex Virus type 1thymidine kinase (HSV-TK). In the present study, cellular uptake of radioiodinated substrates was found to be low in wild type MCA cells, but high in HSV-TK gene expressing cells. The carrier-free substrates, in particular, showed higher cellular uptake than carrier-added compounds. Biodistribution showed that the %ID/g of the MCA-TK/MCA tumor ratio of IVDU injected at 1, 4, and 24 h were 1.1, 0.9 and 1.3, and those of IVFRU were 1.7, 1.7 and 1.8 respectively. Therefore, both IVDU and IVFRU could possibly be used as radiopharmaceuticals to evaluate reporter gene expression. However, IVFRU was more specific and stable than IVDU for selective non-invasive imaging of HSV-TK expression.

Quantitative promoter methylation analysis of multiple cancer-related genes in renal cell tumors

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Oliveira Jorge

2007-07-01

Full Text Available Abstract Background Aberrant promoter hypermethylation of cancer-associated genes occurs frequently during carcinogenesis and may serve as a cancer biomarker. In this study we aimed at defining a quantitative gene promoter methylation panel that might identify the most prevalent types of renal cell tumors. Methods A panel of 18 gene promoters was assessed by quantitative methylation-specific PCR (QMSP in 85 primarily resected renal tumors representing the four major histologic subtypes (52 clear cell (ccRCC, 13 papillary (pRCC, 10 chromophobe (chRCC, and 10 oncocytomas and 62 paired normal tissue samples. After genomic DNA isolation and sodium bisulfite modification, methylation levels were determined and correlated with standard clinicopathological parameters. Results Significant differences in methylation levels among the four subtypes of renal tumors were found for CDH1 (p = 0.0007, PTGS2 (p = 0.002, and RASSF1A (p = 0.0001. CDH1 hypermethylation levels were significantly higher in ccRCC compared to chRCC and oncocytoma (p = 0.00016 and p = 0.0034, respectively, whereas PTGS2 methylation levels were significantly higher in ccRCC compared to pRCC (p = 0.004. RASSF1A methylation levels were significantly higher in pRCC than in normal tissue (p = 0.035. In pRCC, CDH1 and RASSF1A methylation levels were inversely correlated with tumor stage (p = 0.031 and nuclear grade (p = 0.022, respectively. Conclusion The major subtypes of renal epithelial neoplasms display differential aberrant CDH1, PTGS2, and RASSF1A promoter methylation levels. This gene panel might contribute to a more accurate discrimination among common renal tumors, improving preoperative assessment and therapeutic decision-making in patients harboring suspicious renal masses.

Loss of the α2β1 integrin alters human papilloma virus-induced squamous carcinoma progression in vivo and in vitro.

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Thuy Tran

Full Text Available Expression of the α2β1 integrin, a receptor for collagens and laminin, is altered during tumor progression. Recent studies have linked polymorphisms in the α2 integrin gene with oral, squamous cell carcinoma (SCC. To determine the α2β1 integrin's role in SCC progression, we crossed α2-null mice with K14-HPV16 transgenic animals. Pathological progression to invasive carcinoma was evaluated in HPV-positive, α2-null (HPV/KO and HPV-positive, wild-type (HPV/WT animals. α2β1 integrin expression stimulated progression from hyperplasia and papillomatosis to dysplasia with concomitant dermal mast cell infiltration. Moreover, lymph node metastasis was decreased by 31.3% in HPV/KO, compared to HPV/WT, animals. To evaluate the integrin-specific impact on the malignant epithelium versus the microenvironment, we developed primary tumor cell lines. Although transition from dysplasia to carcinoma was unaltered during spontaneous tumor development, isolated primary HPV/KO SCC cell lines demonstrated decreased migration and invasion, compared to HPV/WT cells. When HPV/WT and HPV/KO SCC cells were orthotopically injected into WT or KO hosts, tumor α2β1 integrin expression resulted in decreased tumor latency, regardless of host integrin status. HPV/WT SCC lines failed to demonstrate a proliferative advantage in vitro, however, the HPV/WT tumors demonstrated increased growth compared to HPV/KO SCC lines in vivo. Although contributions of the integrin to the microenvironment cannot be excluded, our studies indicate that α2β1 integrin expression by HPV-transformed keratinocytes modulates SCC growth and progression.

White Matter Fiber-based Analysis of T1w/T2w Ratio Map.

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Chen, Haiwei; Budin, Francois; Noel, Jean; Prieto, Juan Carlos; Gilmore, John; Rasmussen, Jerod; Wadhwa, Pathik D; Entringer, Sonja; Buss, Claudia; Styner, Martin

2017-02-01

To develop, test, evaluate and apply a novel tool for the white matter fiber-based analysis of T1w/T2w ratio maps quantifying myelin content. The cerebral white matter in the human brain develops from a mostly non-myelinated state to a nearly fully mature white matter myelination within the first few years of life. High resolution T1w/T2w ratio maps are believed to be effective in quantitatively estimating myelin content on a voxel-wise basis. We propose the use of a fiber-tract-based analysis of such T1w/T2w ratio data, as it allows us to separate fiber bundles that a common regional analysis imprecisely groups together, and to associate effects to specific tracts rather than large, broad regions. We developed an intuitive, open source tool to facilitate such fiber-based studies of T1w/T2w ratio maps. Via its Graphical User Interface (GUI) the tool is accessible to non-technical users. The framework uses calibrated T1w/T2w ratio maps and a prior fiber atlas as an input to generate profiles of T1w/T2w values. The resulting fiber profiles are used in a statistical analysis that performs along-tract functional statistical analysis. We applied this approach to a preliminary study of early brain development in neonates. We developed an open-source tool for the fiber based analysis of T1w/T2w ratio maps and tested it in a study of brain development.

White matter fiber-based analysis of T1w/T2w ratio map

Science.gov (United States)

Chen, Haiwei; Budin, Francois; Noel, Jean; Prieto, Juan Carlos; Gilmore, John; Rasmussen, Jerod; Wadhwa, Pathik D.; Entringer, Sonja; Buss, Claudia; Styner, Martin

2017-02-01

Purpose: To develop, test, evaluate and apply a novel tool for the white matter fiber-based analysis of T1w/T2w ratio maps quantifying myelin content. Background: The cerebral white matter in the human brain develops from a mostly non-myelinated state to a nearly fully mature white matter myelination within the first few years of life. High resolution T1w/T2w ratio maps are believed to be effective in quantitatively estimating myelin content on a voxel-wise basis. We propose the use of a fiber-tract-based analysis of such T1w/T2w ratio data, as it allows us to separate fiber bundles that a common regional analysis imprecisely groups together, and to associate effects to specific tracts rather than large, broad regions. Methods: We developed an intuitive, open source tool to facilitate such fiber-based studies of T1w/T2w ratio maps. Via its Graphical User Interface (GUI) the tool is accessible to non-technical users. The framework uses calibrated T1w/T2w ratio maps and a prior fiber atlas as an input to generate profiles of T1w/T2w values. The resulting fiber profiles are used in a statistical analysis that performs along-tract functional statistical analysis. We applied this approach to a preliminary study of early brain development in neonates. Results: We developed an open-source tool for the fiber based analysis of T1w/T2w ratio maps and tested it in a study of brain development.

Microenvironment alters epigenetic and gene expression profiles in Swarm rat chondrosarcoma tumors

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Hamm, Christopher A; Wang, Deli; Malchenko, Sergey; Fatima Bonaldo, Maria de; Casavant, Thomas L; Hendrix, Mary JC; Soares, Marcelo B; Stevens, Jeff W; Xie, Hehuang; Vanin, Elio F; Morcuende, Jose A; Abdulkawy, Hakeem; Seftor, Elisabeth A; Sredni, Simone T; Bischof, Jared M

2010-01-01

Chondrosarcomas are malignant cartilage tumors that do not respond to traditional chemotherapy or radiation. The 5-year survival rate of histologic grade III chondrosarcoma is less than 30%. An animal model of chondrosarcoma has been established - namely, the Swarm Rat Chondrosarcoma (SRC) - and shown to resemble the human disease. Previous studies with this model revealed that tumor microenvironment could significantly influence chondrosarcoma malignancy. To examine the effect of the microenvironment, SRC tumors were initiated at different transplantation sites. Pyrosequencing assays were utilized to assess the DNA methylation of the tumors, and SAGE libraries were constructed and sequenced to determine the gene expression profiles of the tumors. Based on the gene expression analysis, subsequent functional assays were designed to determine the relevancy of the specific genes in the development and progression of the SRC. The site of transplantation had a significant impact on the epigenetic and gene expression profiles of SRC tumors. Our analyses revealed that SRC tumors were hypomethylated compared to control tissue, and that tumors at each transplantation site had a unique expression profile. Subsequent functional analysis of differentially expressed genes, albeit preliminary, provided some insight into the role that thymosin-β4, c-fos, and CTGF may play in chondrosarcoma development and progression. This report describes the first global molecular characterization of the SRC model, and it demonstrates that the tumor microenvironment can induce epigenetic alterations and changes in gene expression in the SRC tumors. We documented changes in gene expression that accompany changes in tumor phenotype, and these gene expression changes provide insight into the pathways that may play a role in the development and progression of chondrosarcoma. Furthermore, specific functional analysis indicates that thymosin-β4 may have a role in chondrosarcoma metastasis

Microenvironment alters epigenetic and gene expression profiles in Swarm rat chondrosarcoma tumors

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Hamm Christopher A

2010-09-01

Full Text Available Abstract Background Chondrosarcomas are malignant cartilage tumors that do not respond to traditional chemotherapy or radiation. The 5-year survival rate of histologic grade III chondrosarcoma is less than 30%. An animal model of chondrosarcoma has been established - namely, the Swarm Rat Chondrosarcoma (SRC - and shown to resemble the human disease. Previous studies with this model revealed that tumor microenvironment could significantly influence chondrosarcoma malignancy. Methods To examine the effect of the microenvironment, SRC tumors were initiated at different transplantation sites. Pyrosequencing assays were utilized to assess the DNA methylation of the tumors, and SAGE libraries were constructed and sequenced to determine the gene expression profiles of the tumors. Based on the gene expression analysis, subsequent functional assays were designed to determine the relevancy of the specific genes in the development and progression of the SRC. Results The site of transplantation had a significant impact on the epigenetic and gene expression profiles of SRC tumors. Our analyses revealed that SRC tumors were hypomethylated compared to control tissue, and that tumors at each transplantation site had a unique expression profile. Subsequent functional analysis of differentially expressed genes, albeit preliminary, provided some insight into the role that thymosin-β4, c-fos, and CTGF may play in chondrosarcoma development and progression. Conclusion This report describes the first global molecular characterization of the SRC model, and it demonstrates that the tumor microenvironment can induce epigenetic alterations and changes in gene expression in the SRC tumors. We documented changes in gene expression that accompany changes in tumor phenotype, and these gene expression changes provide insight into the pathways that may play a role in the development and progression of chondrosarcoma. Furthermore, specific functional analysis indicates that

Tumor Restrictive Suicide Gene Therapy for Glioma Controlled by the FOS Promoter.

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Jianqing Pan

Full Text Available Effective suicide gene delivery and expression are crucial to achieving successful effects in gene therapy. An ideal tumor-specific promoter expresses therapeutic genes in tumor cells with minimal normal tissue expression. We compared the activity of the FOS (FBJ murine osteosarcoma viral oncogene homolog promoter with five alternative tumor-specific promoters in glioma cells and non-malignant astrocytes. The FOS promoter caused significantly higher transcriptional activity in glioma cell lines than all alternative promoters with the exception of CMV. The FOS promoter showed 13.9%, 32.4%, and 70.8% of the transcriptional activity of CMV in three glioma cell lines (U87, U251, and U373. Importantly, however, the FOS promoter showed only 1.6% of the transcriptional activity of CMV in normal astrocytes. We also tested the biologic activity of recombinant adenovirus containing the suicide gene herpes simplex virus thymidine kinase (HSV-tk driven by the FOS promoter, including selective killing efficacy in vitro and tumor inhibition rate in vivo. Adenoviral-mediated delivery of the HSV-tk gene controlled by the FOS promoter conferred a cytotoxic effect on human glioma cells in vitro and in vivo. This study suggests that use of the FOS-tk adenovirus system is a promising strategy for glioma-specific gene therapy but still much left for improvement.

Tumor-directed gene therapy in mice using a composite nonviral gene delivery system consisting of the piggyBac transposon and polyethylenimine

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Kang, Yu; Zhang, Xiaoyan; Jiang, Wei; Wu, Chaoqun; Chen, Chunmei; Zheng, Yufang; Gu, Jianren; Xu, Congjian

2009-01-01

Compared with viral vectors, nonviral vectors are less immunogenic, more stable, safer and easier to replication for application in cancer gene therapy. However, nonviral gene delivery system has not been extensively used because of the low transfection efficiency and the short transgene expression, especially in vivo. It is desirable to develop a nonviral gene delivery system that can support stable genomic integration and persistent gene expression in vivo. Here, we used a composite nonviral gene delivery system consisting of the piggyBac (PB) transposon and polyethylenimine (PEI) for long-term transgene expression in mouse ovarian tumors. A recombinant plasmid PB [Act-RFP, HSV-tk] encoding both the herpes simplex thymidine kinase (HSV-tk) and the monomeric red fluorescent protein (mRFP1) under PB transposon elements was constructed. This plasmid and the PBase plasmid were injected into ovarian cancer tumor xenografts in mice by in vivo PEI system. The antitumor effects of HSV-tk/ganciclovir (GCV) system were observed after intraperitoneal injection of GCV. Histological analysis and TUNEL assay were performed on the cryostat sections of the tumor tissue. Plasmid construction was confirmed by PCR analysis combined with restrictive enzyme digestion. mRFP1 expression could be visualized three weeks after the last transfection of pPB/TK under fluorescence microscopy. After GCV admission, the tumor volume of PB/TK group was significantly reduced and the tumor inhibitory rate was 81.96% contrasted against the 43.07% in the TK group. Histological analysis showed that there were extensive necrosis and lymphocytes infiltration in the tumor tissue of the PB/TK group but limited in the tissue of control group. TUNEL assays suggested that the transfected cells were undergoing apoptosis after GCV admission in vivo. Our results show that the nonviral gene delivery system coupling PB transposon with PEI can be used as an efficient tool for gene therapy in ovarian cancer

Tumor suppressor genes are frequently methylated in lymph node metastases of breast cancers

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Xu Jia

2010-07-01

Full Text Available Abstract Introduction Metastasis represents a major adverse step in the progression of breast carcinoma. Lymph node invasion is the most relevant prognostic factor; however little is known on the molecular events associated with lymph node metastasis process. This study is to investigate the status and role of methylation in lymph node metastatic tumors. Materials and methods Bisulfite pyrosequencing is used to screen 6 putative tumor suppressor genes (HIN-1, RASSF1A, RIL, CDH13, RARβ2 and E-cadherin in 38 pairs of primary breast tumors and lymph node metastases. Results We found that HIN-1, CDH13, RIL, RASSF1A and RARβ2 were frequently methylated both in primary and metastatic tissues (range: 55.3%~89.5%. E-cadherin was not frequently methylated in either setting (range: 18.4%~23.7%. The methylation status of HIN-1, CDH13, RIL, and RARβ2 in lymph nodes metastasis were correlated with that in primary tumors. The Pearson correlation values ranged from 0.624 to 0.472 (p values HIN-1 methylation and hormone status in metastatic lymph nodes. Hypermethylation of HIN-1 in metastasis lymph nodes was significantly associated with expression of ER (odds ratio, 1.070; P = 0.024 and with PR (odds ratio, 1.046; P = 0.026. Conclusions This study suggests that hypermethylation of tumor suppressor genes is extended from primary to metastatic tumors during tumor progression.

Intersection of FOXO- and RUNX1-mediated gene expression programs in single breast epithelial cells during morphogenesis and tumor progression.

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Wang, Lixin; Brugge, Joan S; Janes, Kevin A

2011-10-04

Gene expression networks are complicated by the assortment of regulatory factors that bind DNA and modulate transcription combinatorially. Single-cell measurements can reveal biological mechanisms hidden by population averages, but their value has not been fully explored in the context of mRNA regulation. Here, we adapted a single-cell expression profiling technique to examine the gene expression program downstream of Forkhead box O (FOXO) transcription factors during 3D breast epithelial acinar morphogenesis. By analyzing patterns of mRNA fluctuations among individual matrix-attached epithelial cells, we found that a subset of FOXO target genes was jointly regulated by the transcription factor Runt-related transcription factor 1 (RUNX1). Knockdown of RUNX1 causes hyperproliferation and abnormal morphogenesis, both of which require normal FOXO function. Down-regulating RUNX1 and FOXOs simultaneously causes widespread oxidative stress, which arrests proliferation and restores normal acinar morphology. In hormone-negative breast cancers lacking human epidermal growth factor receptor 2 (HER2) amplification, we find that RUNX1 down-regulation is strongly associated with up-regulation of FOXO1, which may be required to support growth of RUNX1-negative tumors. The coordinate function of these two tumor suppressors may provide a failsafe mechanism that inhibits cancer progression.

Dendritic Cell-Based Adjuvant Vaccination Targeting Wilms’ Tumor 1 in Patients with Advanced Colorectal Cancer

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Shigetaka Shimodaira

2015-12-01

Full Text Available Despite significant recent advances in the development of immune checkpoint inhibitors, the treatment of advanced colorectal cancer involving metastasis to distant organs remains challenging. We conducted a phase I study to investigate the safety and immunogenicity of Wilms’ tumor (WT1 class I/II peptides-pulsed dendritic cell DC vaccination for patients with advanced colorectal cancer. Standard treatment comprising surgical resection and chemotherapy was followed by one course of seven biweekly administrations of 1–2 × 107 DCs with 1–2 KE of OK-432 (streptococcal preparation in three patients. Clinical efficacy was confirmed based on WT1 expression using immunohistochemistry on paraffin-embedded tissues and immune monitoring using tetramer analysis and enzyme-linked immunosorbent spot (ELISPOT assays. WT1 expression with human leukocyte antigen (HLA-class I molecules was detected in surgical resected tissues. Adverse reactions to DC vaccinations were tolerable under an adjuvant setting. WT1-specific cytotoxic T cells were detected by both modified WT1-peptide/HLA-A*24:02 tetramer analysis and/or interferon-γ-producing cells through the use of ELISPOT assays after the first DC vaccination. Immunity acquired from DC vaccination persisted for two years with prolonged disease-free and overall survival. The present study indicated that DC vaccination targeting WT1 demonstrated the safety and immunogenicity as an adjuvant therapy in patients with resectable advanced colorectal cancer.

Gene methylation profiles of normal mucosa, and benign and malignant colorectal tumors identify early onset markers

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Vatn Morten

2008-12-01

Full Text Available Abstract Background Multiple epigenetic and genetic changes have been reported in colorectal tumors, but few of these have clinical impact. This study aims to pinpoint epigenetic markers that can discriminate between non-malignant and malignant tissue from the large bowel, i.e. markers with diagnostic potential. The methylation status of eleven genes (ADAMTS1, CDKN2A, CRABP1, HOXA9, MAL, MGMT, MLH1, NR3C1, PTEN, RUNX3, and SCGB3A1 was determined in 154 tissue samples including normal mucosa, adenomas, and carcinomas of the colorectum. The gene-specific and widespread methylation status among the carcinomas was related to patient gender and age, and microsatellite instability status. Possible CIMP tumors were identified by comparing the methylation profile with microsatellite instability (MSI, BRAF-, KRAS-, and TP53 mutation status. Results The mean number of methylated genes per sample was 0.4 in normal colon mucosa from tumor-free individuals, 1.2 in mucosa from cancerous bowels, 2.2 in adenomas, and 3.9 in carcinomas. Widespread methylation was found in both adenomas and carcinomas. The promoters of ADAMTS1, MAL, and MGMT were frequently methylated in benign samples as well as in malignant tumors, independent of microsatellite instability. In contrast, normal mucosa samples taken from bowels without tumor were rarely methylated for the same genes. Hypermethylated CRABP1, MLH1, NR3C1, RUNX3, and SCGB3A1 were shown to be identifiers of carcinomas with microsatellite instability. In agreement with the CIMP concept, MSI and mutated BRAF were associated with samples harboring hypermethylation of several target genes. Conclusion Methylated ADAMTS1, MGMT, and MAL are suitable as markers for early tumor detection.

Bioinformatics Analysis Reveals Genes Involved in the Pathogenesis of Ameloblastoma and Keratocystic Odontogenic Tumor.

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Santos, Eliane Macedo Sobrinho; Santos, Hércules Otacílio; Dos Santos Dias, Ivoneth; Santos, Sérgio Henrique; Batista de Paula, Alfredo Maurício; Feltenberger, John David; Sena Guimarães, André Luiz; Farias, Lucyana Conceição

2016-01-01

Pathogenesis of odontogenic tumors is not well known. It is important to identify genetic deregulations and molecular alterations. This study aimed to investigate, through bioinformatic analysis, the possible genes involved in the pathogenesis of ameloblastoma (AM) and keratocystic odontogenic tumor (KCOT). Genes involved in the pathogenesis of AM and KCOT were identified in GeneCards. Gene list was expanded, and the gene interactions network was mapped using the STRING software. "Weighted number of links" (WNL) was calculated to identify "leader genes" (highest WNL). Genes were ranked by K-means method and Kruskal-Wallis test was used (Preview data was used to corroborate the bioinformatics data. CDK1 was identified as leader gene for AM. In KCOT group, results show PCNA and TP53 . Both tumors exhibit a power law behavior. Our topological analysis suggested leader genes possibly important in the pathogenesis of AM and KCOT, by clustering coefficient calculated for both odontogenic tumors (0.028 for AM, zero for KCOT). The results obtained in the scatter diagram suggest an important relationship of these genes with the molecular processes involved in AM and KCOT. Ontological analysis for both AM and KCOT demonstrated different mechanisms. Bioinformatics analyzes were confirmed through literature review. These results may suggest the involvement of promising genes for a better understanding of the pathogenesis of AM and KCOT.

Expanding the Molecular Signature of Ossifying Fibromyxoid Tumors with 2 Novel Gene Fusions: CREBBP-BCORL1 and KDM2A-WWTR1

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Kao, Yu-Chien; Sung, Yun-Shao; Zhang, Lei; Chen, Chun-Liang; Huang, Shih-Chiang; Antonescu, Cristina R.

2017-01-01

Ossifying fibromyxoid tumor (OFMT) is an uncommon mesenchymal neoplasm of uncertain differentiation and intermediate malignant potential. Recurrent gene fusions involving either PHF1 or BCOR have been found in 85% of OFMT, including typical and malignant examples. As a subset of OFMT still lack known genetic abnormalities, we identified two OFMTs negative for PHF1 and BCOR rearrangements, which were subjected to transcriptome analysis for fusion discovery. The RNA sequencing found a novel CREBBP-BCORL1 fusion candidate in an axillary mass of a 51 year-old male and a KDM2A-WWTR1 in a thigh mass of a 36 year-old male. The gene fusions were validated by RT-PCR and FISH in the index cases and then screened by FISH on 4 additional OFMTs lacking known fusions. An identical CREBBP-BCORL1 fusion was found in an elbow tumor from a 30 year-old male. Both OFMTs with CREBBP-BCORL1 fusions had areas of typical OFMT morphology, exhibiting uniform round to epithelioid cells arranged in cords or nesting pattern in a fibromyxoid stroma. The OFMT with KDM2A-WWTR1 fusion involved dermis and superficial subcutis, being composed of ovoid cells in a fibromyxoid background with hyalinized giant rosettes. The S100 immunoreactivity ranged from very focal to absent. Similar to other known fusion genes in OFMT, BCORL1, CREBBP and KDM2A are also involved in histone modification. In summary, we expand the spectrum of molecular abnormalities in OFMT with 2 novel fusions, CREBBP-BCORL1 and KDM2A-WWTR1, further implicating the epigenetic deregulation as the leading pathogenetic mechanism in OFMT. PMID:27537276

Cloning and Characterizing Genes Involved in Monoterpene Induced Mammary Tumor Regression.

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1996-10-01

AD GRANT NUMBER DAMDI7-94-J-4041 TITLE: Cloning and Characterizing Genes Involved in Monoterpene Induced Mammary Tumor Regression PRINCIPAL...October 1996 Annual (1 Sep 95 - 31 Aug 96) 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS Cloning and Characterizing Genes Involved in Monoterpene Induced... Monoterpene -induced/repressed genes were identified in regressing rat mammary carcinomas treated with dietary limonene using a newly developed method

Microdissecting the Genetic Events in Nephrogenic Rests and Wilms’ Tumor Development

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Charles, Adrian K.; Brown, Keith W.; Berry, P. Jeremy

1998-01-01

Nephrogenic rests are precursor lesions associated with about 40% of Wilms’ tumors. This study identifies genetic steps occurring in the development of Wilms’ tumor. Thirty-four Wilms’ tumors with nephrogenic rests and/or areas of anaplasia were microdissected from paraffin sections to determine whether and at what stage loss of heterozygosity (LOH) occurred, using polymerase chain reaction-based polymorphic markers at 11p13, 11p15, and 16q. LOH at these loci have been identified in Wilms’ tumors and are associated with identified or putative tumor suppressor genes. Three cystic nephromas/cystic partially differentiated nephroblastomas were also examined. LOH was detected in six cases at 11p13 and in six cases at 11p15, and two of these cases had LOH at both loci. All intralobar rests showing LOH also showed LOH in the tumor. A case with a small perilobar rest showed LOH of 11p13 only in the tumor. Five cases showing LOH at 16q were identified (this was identified only in the tumor, and not in the associated rest), and three of these had recurrence of the tumor. Two cases had a WT1 mutation (one germline and the other somatic), as well as LOH in both the intralobar rest and the tumor. A cystic partially differentiated nephroblastoma showed loss at 11p13 and 11p15, as well as at 16q. This study suggests that LOH at 11p13 and 11p15 and WT1 mutations are early events but that LOH at 16q occurs late in the pathogenesis of Wilms’ tumor. Intralobar and perilobar nephrogenic rests are known to have different biological behaviors, and this study suggests that they are genetically different. A multistep model of Wilms’ tumor pathogenesis is supported by these findings. PMID:9736048

Experimental study on anti-tumor effect of pcEgr-IFNγ gene-radiotherapy

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Wu Congmei; Li Xiuyi; Liu Shuzheng

2001-01-01

Objective: To study the anti-tumor effect of IFN γ gene-radiotherapy to murine melanoma and its immunologic mechanism. Methods: pcEgr-IFNγ plasmids were injected locally into tumor, and 36 hours later, the tumors were given 20 Gy X-ray irradiation. Tumor growth at different time, IFN γ expression 3 days later and immunologic indexes 15 days later were detected. Results: At 3-15 days after pcEgr-IFNγ gene-radiotherapy, the tumor growth rate was lower than that of irradiation alone group. It was also lower than that of gene therapy alone group and control plasmid combined with X-ray irradiation group significantly. Day 3 tumor IFN γ expression was higher than that of plasmid treatment alone group. NK activity, IL-2 and IFN γ secretion activities were higher than those of gene therapy alone and irradiation alone groups significantly. Conclusion: The antitumor effect of IFN γ gene-radiotherapy is better than that of either of them applied solely. Its mechanism might be concerned with the higher expression of IFN γ induced by irradiation in tumors and activation of anti-tumor immunologic functions

Association Study of Tumor Necrosis Factor Receptor 1 (TNFR1 Gene Polymorphisms with Schizophrenia in the Polish Population

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Renata Suchanek-Raif

2017-01-01

Full Text Available Schizophrenia is a devastating mental disorder with undetermined aetiology. Previous research has suggested that dysregulation of proinflammatory cytokines and their receptors plays a role in developing schizophrenia. We examined the association of the three single nucleotide polymorphisms (SNPs; rs4149576, rs4149577, and rs1860545 in the tumor necrosis factor receptor 1 (TNFR1 gene with the development and psychopathology of paranoid schizophrenia in the Polish Caucasian sample consisting of 388 patients and 657 control subjects. The psychopathology was assessed using a five-factor model of the Positive and Negative Syndrome Scale (PANSS. SNPs were genotyped using the TaqMan 5′-exonuclease allelic discrimination assay. The SNPs tested were not associated with a predisposition to paranoid schizophrenia in either the entire sample or after stratification according to gender. However, rs4149577 and rs1860545 SNPs were associated with the intensity of the PANSS excitement symptoms in men, which may contribute to the risk of violent behavior. Polymorphisms in the TNFR1 gene may have an impact on the symptomatology of schizophrenia in men.

Down-regulation of SFRP1 as a putative tumor suppressor gene can contribute to human hepatocellular carcinoma

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Huang, Jian; Zhang, Yun-Li; Teng, Xiao-Mei; Lin, Yun; Zheng, Da-Li; Yang, Peng-Yuan; Han, Ze-Guang

2007-01-01

Hepatocellular carcinoma (HCC) is one of the most common cancers in the world. SFRP1 (the secreted frizzled-related protein 1), a putative tumor suppressor gene mapped onto chromosome 8p12-p11.1, the frequent loss of heterozygosity (LOH) region in human HCC, encodes a Wingless-type (Wnt) signaling antagonist and is frequently inactivated by promoter methylation in many human cancers. However, whether the down-regulation of SFRP1 can contribute to hepatocarcinogenesis still remains unclear. We investigated the expression of SFRP1 through real time RT-PCR and immunohistochemistry staining. The cell growth and colony formation were observed as the overexpression and knockdown of SFRP1. The DNA methylation status within SFRP1 promoter was analyzed through methylation-specific PCR or bisulphate-treated DNA sequencing assays. Loss of heterozygosity was here detected with microsatellite markers. SFRP1 was significantly down-regulated in 76.1% (35/46) HCC specimens at mRNA level and in 30% (30/100) HCCs indicated by immunohistochemistry staining, as compared to adjacent non-cancerous livers. The overexpression of SFRP1 can significantly inhibit the cell growth and colony formation of YY-8103, SMMC7721, and Hep3B cells. The RNA interference against the constitutional SFRP1 in the offspring SMMC7721 cells, which were stably transfected by ectopic SFRP1, can markedly promote cell growth of these cells. LOH of both microsatellite markers D8S532 and D8SAC016868 flanking the gene locus was found in 13% (6 of 46 HCCs) and 6.5% (3 of 46 HCCs) of the informative cases, respectively, where 5 of 8 HCC specimens with LOH showed the down-regulation of SFRP1. DNA hypermethylation within SFRP1 promoter was identified in two of three HCC specimens without SFRP1 expression. Moreover, the DNA methylation of SFRP1 promoter was significantly reduced, along with the re-expression of the gene, in those HCC cell lines, Bel7404, QGY7701, and MHCC-H, as treated by DAC. Our data suggested that the

Correlation of Dynamic PET and Gene Array Data in Patients with Gastrointestinal Stromal Tumors

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Ludwig G. Strauss

2012-01-01

Full Text Available Introduction. The results obtained with dynamic PET (dPET were compared to gene expression data obtained in patients with gastrointestinal stromal tumors (GIST. The primary aim was to assess the association of the dPET results and gene expression data. Material and Methods. dPET was performed following the injection of F-18-fluorodeoxyglucose (FDG in 22 patients with GIST. All patients were examined prior to surgery for staging purpose. Compartment and noncompartment models were used for the quantitative evaluation of the dPET examinations. Gene array data were based on tumor specimen obtained by surgery after the PET examinations. Results. The data analysis revealed significant correlations for the dPET parameters and the expression of zinc finger genes (znf43, znf85, znf91, znf189. Furthermore, the transport of FDG (k1 was associated with VEGF-A. The cell cycle gene cyclin-dependent kinase inhibitor 1C was correlated with the maximum tracer uptake (SUVmax in the tumors. Conclusions. The data demonstrate a dependency of the tracer kinetics on genes associated with prognosis in GIST. Furthermore, angiogenesis and cell proliferation have an impact on the tracer uptake.

Connexin 43 Gene Therapy Delivered by Polymer-Modified Salmonella in Murine Tumor Models

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Wei-Kuang Wang

2014-04-01

Full Text Available The use of preferentially tumor-targeting bacteria as vectors is one of the most innovative approaches for the treatment of cancer. This method is based on the observation that some obligate or facultative anaerobic bacteria are capable of selectively multiplying in tumors and inhibiting their growth. Previously, we found that the tumor-targeting efficiency of Salmonella could be modulated by modifying the immune response to these bacteria by coating them with poly(allylamine hydrochloride (PAH, and these organisms are designated PAH-S.C. (S. choleraesuis. PAH can provide a useful platform for the chemical modification of Salmonella, perhaps by allowing a therapeutic gene to bind to tumor-targeting Salmonella. This study aimed to investigate the benefits of the use of PAH-S.C. for gene delivery. To evaluate this modulation, the invasion activity and gene transfer of DNA-PAH-S.C. were measured in vitro and in vivo. Treatment with PAH-S.C. carrying a tumor suppressor gene (connexin 43 resulted in inhibition of tumor growth, which suggested that tumor-targeted gene therapy using PAH-S.C. carrying a therapeutic gene could exert antitumor activities. This technique represents a promising strategy for the treatment of tumors.

A case of pancreatic neuroendocrine tumor in a patient with neurofibromatosis-1

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Nishi Takeshi

2012-07-01

Full Text Available Abstract Patients with neurofibromatosis-1 (NF-1 sometime develop neuroendocrine tumors (NET. Although these NETs usually occur in the duodenum or peri-ampullary region, they occasionally grow in the pancreas (PNET. A 62-year-old man with NF-1 had mild liver dysfunction and was admitted to our hospital for further examination. An abdominal contrast-enhanced computed tomography scan demonstrated a 30-mm tumor in the head of the pancreas. The scan showed an invasion of the tumor into the duodenum, and biopsy under an endoscopic ultrasonography indicated that the tumor was a NET. A subtotal stomach-preserving pancreaticoduodenectomy was performed. Macroscopically, the pancreatic tumor was white and elastic hard. Microscopically, tumor cells were composed of ribbons, cords, and solid nests with an acinus-like structure. The tumor was diagnosed as NET G2 according to the WHO classification (2010. The product of theNF-1 gene, i.e., neurofibromin, was weakly positive in the tumor cells, suggesting that the tumor was induced by a mutation in the NF-1 gene. This is the seventh case of PNET arising in NF-1 patients worldwide.

Expanding the Molecular Signature of Ossifying Fibromyxoid Tumors with 2 Novel Gene Fusions: CREBBP-BCORL1 and KDM2A-WWTR1

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Kao, Yu-Chien; Sung, Yun-Shao; Zhang, Lei; Chen, Chun-Liang; Huang, Shih-Chiang; Antonescu, Cristina R.

2016-01-01

Ossifying fibromyxoid tumor (OFMT) is an uncommon mesenchymal neoplasm of uncertain differentiation and intermediate malignant potential. Recurrent gene fusions involving either PHF1 or BCOR have been found in 85% of OFMT, including typical and malignant examples. As a subset of OFMT still lack known genetic abnormalities, we identified two OFMTs negative for PHF1 and BCOR rearrangements, which were subjected to transcriptome analysis for fusion discovery. The RNA sequencing found a novel CRE...

CRISPR/Cas9 Engineering of Adult Mouse Liver Demonstrates That the Dnajb1-Prkaca Gene Fusion Is Sufficient to Induce Tumors Resembling Fibrolamellar Hepatocellular Carcinoma.

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Engelholm, Lars H; Riaz, Anjum; Serra, Denise; Dagnæs-Hansen, Frederik; Johansen, Jens V; Santoni-Rugiu, Eric; Hansen, Steen H; Niola, Francesco; Frödin, Morten

2017-12-01

Fibrolamellar hepatocellular carcinoma (FL-HCC) is a primary liver cancer that predominantly affects children and young adults with no underlying liver disease. A somatic, 400 Kb deletion on chromosome 19 that fuses part of the DnaJ heat shock protein family (Hsp40) member B1 gene (DNAJB1) to the protein kinase cAMP-activated catalytic subunit alpha gene (PRKACA) has been repeatedly identified in patients with FL-HCC. However, the DNAJB1-PRKACA gene fusion has not been shown to induce liver tumorigenesis. We used the CRISPR/Cas9 technique to delete in mice the syntenic region on chromosome 8 to create a Dnajb1-Prkaca fusion and monitored the mice for liver tumor development. We delivered CRISPR/Cas9 vectors designed to juxtapose exon 1 of Dnajb1 with exon 2 of Prkaca to create the Dnajb1-Prkaca gene fusion associated with FL-HCC, or control Cas9 vector, via hydrodynamic tail vein injection to livers of 8-week-old female FVB/N mice. These mice did not have any other engineered genetic alterations and were not exposed to liver toxins or carcinogens. Liver tissues were collected 14 months after delivery; genomic DNA was analyzed by PCR to detect the Dnajb1-Prkaca fusion, and tissues were characterized by histology, immunohistochemistry, RNA sequencing, and whole-exome sequencing. Livers from 12 of the 15 mice given the vectors to induce the Dnajb1-Prkaca gene fusion, but none of the 11 mice given the control vector, developed neoplasms. The tumors contained the Dnajb1-Prkaca gene fusion and had histologic and cytologic features of human FL-HCCs: large polygonal cells with granular, eosinophilic, and mitochondria-rich cytoplasm, prominent nucleoli, and markers of hepatocytes and cholangiocytes. In comparing expression levels of genes between the mouse tumor and non-tumor liver cells, we identified changes similar to those detected in human FL-HCC, which included genes that affect cell cycle and mitosis regulation. Genomic analysis of mouse neoplasms induced by

The tumor suppressor PTEN inhibits EGF-induced TSP-1 and TIMP-1 expression in FTC-133 thyroid carcinoma cells

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Soula-Rothhut, Mahdhia; Coissard, Cyrille; Sartelet, Herve; Boudot, Cedric; Bellon, Georges; Martiny, Laurent; Rothhut, Bernard

2005-01-01

Thrombospondin-1 (TSP-1) is a multidomain extracellular macromolecule that was first identified as natural modulator of angiogenesis and tumor growth. In the present study, we found that epidermal growth factor (EGF) up-regulated TSP-1 expression in FTC-133 (primary tumor) but not in FTC-238 (lung metastasis) thyroid cancer cells. Both EGF and TSP-1 induced expression of tissue inhibitor of metalloproteinase-1 (TIMP-1) in a mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) and phosphatidylinositol 3-kinase (PI3-kinase)-dependent manner. In FTC-133 cells, EGF induced proliferation in a TSP-1- and TIMP-1-dependent manner. In addition, we determined that re-expression of the tumor suppressor protein PTEN induced cell death, an effect that correlated with a block of Akt kinase phosphorylation. EGF-induced TSP-1 and TIMP-1 promoter activity and protein expression were inhibited in FTC-133 cells stably expressing wtPTEN but not in cells expressing mutant PTEN. Furthermore, we found that wtPTEN inhibited EGF-but not TSP-1-stimulated FTC-133 cell migration and also inhibited invasion induced by EGF and by TSP-1. Finally, an antibody against TSP-1 reversed EGF-stimulated FTC-133 cell invasion as well as the constitutive invasive potential of FTC-238 cells. Overall, our results suggest that PTEN can function as an important modulator of extracellular matrix proteins in thyroid cancer. Therefore, analyzing differential regulation of TSP-1 by growth factors such as EGF can be helpful in understanding thyroid cancer development

Expanding the molecular signature of ossifying fibromyxoid tumors with two novel gene fusions: CREBBP-BCORL1 and KDM2A-WWTR1.

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Kao, Yu-Chien; Sung, Yun-Shao; Zhang, Lei; Chen, Chun-Liang; Huang, Shih-Chiang; Antonescu, Cristina R

2017-01-01

Ossifying fibromyxoid tumor (OFMT) is an uncommon mesenchymal neoplasm of uncertain differentiation and intermediate malignant potential. Recurrent gene fusions involving either PHF1 or BCOR have been found in 85% of OFMT, including typical and malignant examples. As a subset of OFMT still lack known genetic abnormalities, we identified two OFMTs negative for PHF1 and BCOR rearrangements, which were subjected to transcriptome analysis for fusion discovery. The RNA sequencing found a novel CREBBP-BCORL1 fusion candidate in an axillary mass of a 51 year-old male and a KDM2A-WWTR1 in a thigh mass of a 36 year-old male. The gene fusions were validated by RT-PCR and FISH in the index cases and then screened by FISH on 4 additional OFMTs lacking known fusions. An identical CREBBP-BCORL1 fusion was found in an elbow tumor from a 30 year-old male. Both OFMTs with CREBBP-BCORL1 fusions had areas of typical OFMT morphology, exhibiting uniform round to epithelioid cells arranged in cords or nesting pattern in a fibromyxoid stroma. The OFMT with KDM2A-WWTR1 fusion involved dermis and superficial subcutis, being composed of ovoid cells in a fibromyxoid background with hyalinized giant rosettes. The S100 immunoreactivity ranged from very focal to absent. Similar to other known fusion genes in OFMT, BCORL1, CREBBP and KDM2A are also involved in histone modification. In summary, we expand the spectrum of molecular abnormalities in OFMT with 2 novel fusions, CREBBP-BCORL1 and KDM2A-WWTR1, further implicating the epigenetic deregulation as the leading pathogenetic mechanism in OFMT. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Comparative analyses of gene copy number and mRNA expression in GBM tumors and GBM xenografts

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Hodgson, J. Graeme; Yeh, Ru-Fang; Ray, Amrita; Wang, Nicholas J.; Smirnov, Ivan; Yu, Mamie; Hariono, Sujatmi; Silber, Joachim; Feiler, Heidi S.; Gray, Joe W.; Spellman, Paul T.; Vandenberg, Scott R.; Berger, Mitchel S.; James, C. David

2009-04-03

Development of model systems that recapitulate the molecular heterogeneity observed among glioblastoma multiforme (GBM) tumors will expedite the testing of targeted molecular therapeutic strategies for GBM treatment. In this study, we profiled DNA copy number and mRNA expression in 21 independent GBM tumor lines maintained as subcutaneous xenografts (GBMX), and compared GBMX molecular signatures to those observed in GBM clinical specimens derived from the Cancer Genome Atlas (TCGA). The predominant copy number signature in both tumor groups was defined by chromosome-7 gain/chromosome-10 loss, a poor-prognosis genetic signature. We also observed, at frequencies similar to that detected in TCGA GBM tumors, genomic amplification and overexpression of known GBM oncogenes, such as EGFR, MDM2, CDK6, and MYCN, and novel genes, including NUP107, SLC35E3, MMP1, MMP13, and DDX1. The transcriptional signature of GBMX tumors, which was stable over multiple subcutaneous passages, was defined by overexpression of genes involved in M phase, DNA replication, and chromosome organization (MRC) and was highly similar to the poor-prognosis mitosis and cell-cycle module (MCM) in GBM. Assessment of gene expression in TCGA-derived GBMs revealed overexpression of MRC cancer genes AURKB, BIRC5, CCNB1, CCNB2, CDC2, CDK2, and FOXM1, which form a transcriptional network important for G2/M progression and/or checkpoint activation. Our study supports propagation of GBM tumors as subcutaneous xenografts as a useful approach for sustaining key molecular characteristics of patient tumors, and highlights therapeutic opportunities conferred by this GBMX tumor panel for testing targeted therapeutic strategies for GBM treatment.

Radiolabeled Probes Targeting Hypoxia-Inducible Factor-1-Active Tumor Microenvironments

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Masashi Ueda

2014-01-01

Full Text Available Because tumor cells grow rapidly and randomly, hypoxic regions arise from the lack of oxygen supply in solid tumors. Hypoxic regions in tumors are known to be resistant to chemotherapy and radiotherapy. Hypoxia-inducible factor-1 (HIF-1 expressed in hypoxic regions regulates the expression of genes related to tumor growth, angiogenesis, metastasis, and therapy resistance. Thus, imaging of HIF-1-active regions in tumors is of great interest. HIF-1 activity is regulated by the expression and degradation of its α subunit (HIF-1α, which is degraded in the proteasome under normoxic conditions, but escapes degradation under hypoxic conditions, allowing it to activate transcription of HIF-1-target genes. Therefore, to image HIF-1-active regions, HIF-1-dependent reporter systems and injectable probes that are degraded in a manner similar to HIF-1α have been recently developed and used in preclinical studies. However, no probe currently used in clinical practice directly assesses HIF-1 activity. Whether the accumulation of 18F-FDG or 18F-FMISO can be utilized as an index of HIF-1 activity has been investigated in clinical studies. In this review, the current status of HIF-1 imaging in preclinical and clinical studies is discussed.

Downregulation of ATM Gene and Protein Expression in Canine Mammary Tumors.

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Raposo-Ferreira, T M M; Bueno, R C; Terra, E M; Avante, M L; Tinucci-Costa, M; Carvalho, M; Cassali, G D; Linde, S D; Rogatto, S R; Laufer-Amorim, R

2016-11-01

The ataxia telangiectasia mutated (ATM) gene encodes a protein associated with DNA damage repair and maintenance of genomic integrity. In women, ATM transcript and protein downregulation have been reported in sporadic breast carcinomas, and the absence of ATM protein expression has been associated with poor prognosis. The aim of this study was to evaluate ATM gene and protein expression in canine mammary tumors and their association with clinical outcome. ATM gene and protein expression was evaluated by reverse transcription-quantitative polymerase chain reaction and immunohistochemistry, respectively, in normal mammary gland samples (n = 10), benign mammary tumors (n = 11), nonmetastatic mammary carcinomas (n = 19), and metastatic mammary carcinomas (n = 11). Lower ATM transcript levels were detected in benign mammary tumors and carcinomas compared with normal mammary glands (P = .011). Similarly, lower ATM protein expression was observed in benign tumors (P = .0003), nonmetastatic mammary carcinomas (P ATM gene or protein levels were detected among benign tumors and nonmetastatic and metastatic mammary carcinomas (P > .05). The levels of ATM gene or protein expression were not significantly associated with clinical and pathological features or with survival. Similar to human breast cancer, the data in this study suggest that ATM gene and protein downregulation is involved in canine mammary gland tumorigenesis. © The Author(s) 2016.

Differential peripheral blood gene expression profile based on Her2 expression on primary tumors of breast cancer patients.

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Oana Tudoran

Full Text Available Breast cancer prognosis and treatment is highly dependent on the molecular features of the primary tumors. These tumors release specific molecules into the environment that trigger characteristic responses into the circulatory cells. In this study we investigated the expression pattern of 84 genes known to be involved in breast cancer signaling in the peripheral blood of breast cancer patients with ER-, PR- primary tumors. The patients were grouped according to Her2 expression on the primary tumors in Her2+ and Her2- cohorts. Transcriptional analysis revealed 15 genes to be differentially expressed between the two groups highlighting that Her2 signaling in primary tumors could be associated with specific blood gene expression. We found CCNA1 to be up-regulated, while ERBB2, RASSF1, CDH1, MKI67, GATA3, GLI1, SFN, PTGS2, JUN, NOTCH1, CTNNB1, KRT8, SRC, and HIC1 genes were down-regulated in the blood of triple negative breast cancer patients compared to Her2+ cohort. IPA network analysis predicts that the identified genes are interconnected and regulate each other. These genes code for cell cycle regulators, cell adhesion molecules, transcription factors or signal transducers that modulate immune signaling, several genes being also associated with cancer progression and treatment response. These results indicate an altered immune signaling in the peripheral blood of triple negative breast cancer patients. The involvement of the immune system is necessary in favorable treatment response, therefore these results could explain the low response rates observed for triple negative breast cancer patients.

MUTATIONS OF THE SMARCB1 GENE IN HUMAN CANCERS

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D. S. Mikhaylenko

2016-01-01

Full Text Available In the recent years, the full exome sequencing helped to reveal a  set of mutations in the genes that are not oncogenes or tumor suppressor genes by definition, but play an important role in carcinogenesis and encode proteins involved in chromatin remodeling. Among chromatin remodeling systems, which operate through the ATP-dependent mechanism, the complex SWI/ SNF attracts the great attention. The complex consists of the catalytic ATPase (SMARCA2/4, a group of conservative core subunits (SMARCB1, SMARCC1/2, and variant subunits. Abnormalities in the genes coding for each of these components have been identified as driver mutations in various human tumors. The SMARCB1 gene is of interest for practical oncogenetics, with its typical genotype-phenotype correlations. Germinal inactivating mutations (frameshift insertions/deletions, full deletions of the gene, nonsense mutations lead to development of rhabdoid tumors in the kidneys and the brain in children in their first years of life, or even in utero. These tumors are highly malignant (Rhabdoid Tumor Predisposition Syndrome 1 – RTPS1. If a mutation carrier survives his/hers four years of life without manifestation RTPS1 with a missense mutation or has the mutation in the "hot spot" of the first or the last exon, then he/she will not develop rhabdoid tumors, but after 20 years of life, shwannomatosis may develop as multiple benign tumors of peripheral nerves. Finally, some point mutations in the exons 8–9 can result in Coffin-Siris syndrome characterized by mental retardation and developmental disorders, but no neoplasms. In this regard, rational referral of patients for direct DNA diagnostics of each of the described disease entities plays an important role, based on respective minimal criteria, as well as necessity of further development of NGS technologies (full genome and full exome sequencing that are able to sequence not only individual exons, but all candidate genes of the

Gene Discovery in Prostate Cancer: Functional Identification and Isolation of PAC-1, a Novel Tumor Suppressor Gene Within Chromosome 10p

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1999-09-01

I.. Zbar. B.. androle for the VHL gene in the development of hyperplasia in a number Lerman. I. I. Identification of the son Hippel-Lindau disease...of heterozy- gosity of chromosome 3p markers in small-cell lung cancer. Nature (Lond.). 329: eleguns produced hyperplasia in all tissues (26...central fibrovascular core lined by cuboidal tumor cells. Tumor weights were determined (Fig. 2d). At the end of 47 days after cells were

15-Hydroxyprostaglandin dehydrogenase inactivation as a mechanism of resistance to celecoxib chemoprevention of colon tumors.

LENUS (Irish Health Repository)

Yan, Min

2009-06-09

Pharmacologic inhibitors of the prostaglandin-synthesizing COX-2 oncogene prevent the development of premalignant human colon adenomas. However, resistance to treatment is common. In this study, we show that the adenoma prevention activity of the COX-2 inhibitor celecoxib requires the concomitant presence of the 15-hydroxyprostaglandin dehydrogenase (15-PGDH) tumor suppressor gene, and that loss of 15-PGDH expression imparts resistance to celecoxib\\'s anti-tumor effects. We first demonstrate that the adenoma-preventive activity of celecoxib is abrogated in mice genetically lacking 15-PGDH. In FVB mice, celecoxib prevents 85% of azoxymethane-induced tumors >1 mm in size, but is essentially inactive in preventing tumor induction in 15-PGDH-null animals. Indeed, celecoxib treated 15-PGDH null animals develop more tumors than do celecoxib naive WT mice. In parallel with the loss of tumor prevention activity, celecoxib-mediated suppression of colonic PGE(2) levels is also markedly attenuated in 15-PGDH-null versus WT mice. Finally, as predicted by the murine models, humans with low colonic 15-PGDH levels also exhibit celecoxib resistance. Specifically, in a colon adenoma prevention trial, in all cases tested, individuals who developed new adenomas while receiving celecoxib treatment were also found as having low colonic 15-PGDH levels.

Heme oxygenase-1 accelerates tumor angiogenesis of human pancreatic cancer.

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Sunamura, Makoto; Duda, Dan G; Ghattas, Maivel H; Lozonschi, Lucian; Motoi, Fuyuhiko; Yamauchi, Jun-Ichiro; Matsuno, Seiki; Shibahara, Shigeki; Abraham, Nader G

2003-01-01

Angiogenesis is necessary for the continued growth of solid tumors, invasion and metastasis. Several studies clearly showed that heme oxygenase-1 (HO-1) plays an important role in angiogenesis. In this study, we used the vital microscope system, transparent skinfold model, lung colonization model and transduced pancreatic cancer cell line (Panc-1)/human heme oxygenase-1 (hHO-1) cells, to precisely analyze, for the first time, the effect of hHO-1 gene on tumor growth, angiogenesis and metastasis. Our results revealed that HO-1 stimulates angiogenesis of pancreatic carcinoma in severe combined immune deficient mice. Overexpression of human hHO-1 after its retroviral transfer into Panc-1 cells did not interfere with tumor growth in vitro. While in vivo the development of tumors was accelerated upon transfection with hHO-1. On the other hand, inhibition of heme oxygenase (HO) activity by stannous mesoporphyrin was able transiently to delay tumor growth in a dose dependent manner. Tumor angiogenesis was markedly increased in Panc-1/hHO-1 compared to mock transfected and wild type. Lectin staining and Ki-67 proliferation index confirmed these results. In addition hHO-1 stimulated in vitro tumor angiogenesis and increased endothelial cell survival. In a lung colonization model, overexpression of hHO-1 increased the occurrence of metastasis, while inhibition of HO activity by stannous mesoporphyrin completely inhibited the occurrence of metastasis. In conclusion, overexpression of HO-1 genes potentiates pancreatic cancer aggressiveness, by increasing tumor growth, angiogenesis and metastasis and that the inhibition of the HO system may be of useful benefit for the future treatment of the disease.

Dissecting Time- from Tumor-Related Gene Expression Variability in Bilateral Breast Cancer

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Maurizio Callari

2018-01-01

Full Text Available Metachronous (MBC and synchronous bilateral breast tumors (SBC are mostly distinct primaries, whereas paired primaries and their local recurrences (LRC share a common origin. Intra-pair gene expression variability in MBC, SBC, and LRC derives from time/tumor microenvironment-related and tumor genetic background-related factors and pairs represents an ideal model for trying to dissect tumor-related from microenvironment-related variability. Pairs of tumors derived from women with SBC (n = 18, MBC (n = 11, and LRC (n = 10 undergoing local-regional treatment were profiled for gene expression; similarity between pairs was measured using an intraclass correlation coefficient (ICC computed for each gene and compared using analysis of variance (ANOVA. When considering biologically unselected genes, the highest correlations were found for primaries and paired LRC, and the lowest for MBC pairs. By instead limiting the analysis to the breast cancer intrinsic genes, correlations between primaries and paired LRC were enhanced, while lower similarities were observed for SBC and MBC. Focusing on stromal-related genes, the ICC values decreased for MBC and were significantly different from SBC. These findings indicate that it is possible to dissect intra-pair gene expression variability into components that are associated with genetic origin or with time and microenvironment by using specific gene subsets.

Enhancement of anticancer effect of interferon-γ gene transfer against interferon-γ-resistant tumor by depletion of tumor-associated macrophages.

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Kiyota, Tsuyoshi; Takahashi, Yuki; Watcharanurak, Kanitta; Nishikawa, Makiya; Ohara, Saori; Ando, Mitsuru; Watanabe, Yoshihiko; Takakura, Yoshinobu

2014-05-05

Tumor-associated macrophages (TAMs) negatively affect the therapeutic effects of anticancer agents. To examine the role of TAMs in interferon (IFN)-γ gene therapy, we selected two types of solid tumors, which varied in the number of TAMs, and investigated the effects of IFN-γ gene transfer on tumor growth. Many TAMs were detected in the solid tumors of murine adenocarcinoma colon-26 cells, whereas few TAMs were detected in murine melanoma B16-BL6 cells. IFN-γ gene transfer hardly suppressed the growth of colon-26 tumors, whereas it was effective in suppressing the growth of B16-BL6 tumors. The antiproliferative effects of IFN-γ on cultured colon-26 cells were similar to those on cultured B16-BL6 cells. To evaluate the role of TAMs, we injected clodronate liposomes (CLs) modified with poly(ethylene glycol) (PEG) to functionally deplete TAMs in tumor-bearing mice. Repeated injections of PEG-CLs significantly retarded the growth of colon-26 tumors and combination with IFN-γ gene transfer further inhibited the growth. In contrast, PEG-CLs hardly retarded the growth of B16-BL6 tumors. These results clearly indicate that TAM depletion is effective in enhancing the therapeutic effect of IFN-γ in TAM-repleted and IFN-γ-resistant tumors.

Andrographolide promotes vincristine-induced SK-NEP-1 tumor cell death via PI3K-AKT-p53 signaling pathway

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Zhang, Mingsheng; Xue, Enda; Shao, Wei

2016-01-01

Background Nephroblastoma (Wilms’ tumor [WT]) is the most common malignant renal cancer in children. Although the outcome of WT has significantly improved as a result of the combination of surgery, chemotherapy, and radiotherapy; in some cases WT results in severe complications. Thus, novel strategies that would decrease treatment burden are required. The aim of the current study was to investigate the synergistic antitumor effect of andrographolide (AND) in combination with vincristine (VCR) on WT cells. Methods Cell Counting Kit-8 assay was used to investigate the synergistic antiproliferation effect of AND and/or VCR on SK-NEP-1 cells in vitro. Meanwhile, SK-NEP-1 xenografts were used to detect the antitumor effect in vivo. Apoptosis and autophagy were then detected by Annexin V, monodansylcadaverine staining. Finally, the underlying signaling transduction was determined with Western blotting. Results The combination of AND with VCR significantly suppressed SK-NEP-1 cell proliferation in vitro and inhibited xenograft tumor growth in vivo, compared with AND or VCR treatment alone. In addition, the synergistic antitumor effect of AND on the cells was due to an increased apoptosis, not autophagy. Moreover, PI3K-AKT-p53 signaling pathway was involved in the process of combination treatment, which was confirmed when a selective AKT activator was applied. Conclusion The combination of AND with VCR has a strong synergistic antitumor effect on WT via PI3K-AKT-p53 signaling pathway, thereby representing a potential treatment for WT in the near future. PMID:27729773

Hypoxic inactivation of glycogen synthase kinase-3β promotes gastric tumor growth and angiogenesis by facilitating hypoxia-inducible factor-1 signaling.

Science.gov (United States)

Ko, Young San; Cho, Sung Jin; Park, Jinju; Choi, Yiseul; Lee, Jae-Seon; Youn, Hong-Duk; Kim, Woo Ho; Kim, Min A; Park, Jong-Wan; Lee, Byung Lan

2016-09-01

Since the molecular mechanism of hypoxic adaptation in cancer cells is cell-type specific, we investigated whether glycogen synthase kinase-3β (GSK-3β) activation is involved in hypoxia-induced gastric tumor promotion. Stable gastric cancer cell lines (SNU-638, SNU-484, MKN1, and MKN45) were cultured under hypoxic conditions. Cells overexpressing wild-type GSK-3β (WT-GSK-3β) or kinase-dead mutant of GSK-3β (KD-GSK-3β) were generated and used for cell culture and animal studies. In cell culture experiments, hypoxia decreased GSK-3β activation in gastric cancer cells. Cell viability and the expressions of HIF-1α protein and VEGF mRNA in gastric cancer cells were higher in KD-GSK-3β transfectants than in WT-GSK-3β transfectants under hypoxic conditions, but not under normoxic conditions. Gastric cancer xenografts showed that tumor growth, microvessel area, HIF-1α activation, and VEGF expression were higher in KD-GSK-3β tumors than in WT-GSK-3β tumors in vivo. In addition, the expression of hypoxia-induced HIF-1α protein was regulated by GSK-3β at the translational level. Our data suggest that GSK-3β is involved in hypoxic adaptation of gastric cancer cells as an inhibitory upstream regulator of the HIF-1α/VEGF signaling pathway. © 2016 APMIS. Published by John Wiley & Sons Ltd.

Tandem duplication of 11p12-p13 in a child with borderline development delay and eye abnormalities: dose effect of the PAX6 gene product?

NARCIS (Netherlands)

Aalfs, C. M.; Fantes, J. A.; Wenniger-Prick, L. J.; Sluijter, S.; Hennekam, R. C.; van Heyningen, V.; Hoovers, J. M.

1997-01-01

We report on a girl with a duplication of chromosome band 11p12-->13, which includes the Wilms tumor gene (WT1) and the aniridia gene (PAX6). The girl had borderline developmental delay, mild facial anomalies, and eye abnormalities. Eye findings were also present in most of the 11 other published

The effect of endostatin gene in combination with radiotherapy on rats with implanted tumor

International Nuclear Information System (INIS)

Li Yong; Jin Ning; Yang Haishan; Piao Chunji; Lv Zhe

2005-01-01

Objective: To study the combination therapy effect of the radiotherapy with endostatin gene therapy on the rats with implanted tumor. Methods: Immediate Walker-256 cancerous ascetic injection method was used to make a rat tumor-bearing model, then the tumor was treated with saline, endostatin gene, irradiation or endostatin gene plus irradiation. The tumor growth rate and weight were observed, Western blot and RT-PCR were adopted to check the expressions of endostatin mRNA and protein. Results: The expressions of endostatin mRNA and protein were significant in the gene therapy group and the gene plus radiotherapy group, but there was a significant difference between these two groups. As compared with the control group, the tumor growth rate and weight decreased significantly in all the therapy groups (P 0.05). Conclusion: After the pCMV-Endostatin was induced, the expressions of endostatin mRNA and protein was significant in Walker-256 tumor and the tumor growth was inhibited. However, the effect of the endostatin gene plus radiotherapy was obviously better than that of the endostatin gene therapy group or the radiotherapy group for inhibiting tumor growth. (authors)

Expression of multidrug resistance-related protein (MRP-1), lung resistance-related protein (LRP) and topoisomerase-II (TOPO-II) in Wilms' tumor: immunohistochemical study using TMA methodology.

Science.gov (United States)

Fridman, Eduard; Skarda, Jozef; Pinthus, Jonatan H; Ramon, Jonathan; Mor, Yoran

2008-06-01

MRP-1, LRP and TOPO-II are all associated with protection of the cells from the adverse effects of various chemotherapeutics. The aim of this study was to measure the expression of these proteins in Wilms' tumor (WT). TMA block was constructed from 14 samples of WT's and from xenografts derived from them. Sections of the TMA were used for immunostaining against MRP-1, LRP and TOPO-IIa. All normal kidneys expressed MRP-1 but were either weakly or negatively stained for LRP and TOPO-IIa. In WT samples, MRP-1 was universally expressed, exclusively in the tubular component, while there was no expression of LRP and TOPO-IIa showed heterogeneous distribution. The xenografts varied in their MRP-1 and TOPO-IIa expression and exhibited weak/negative staining of LRP. This study shows that although all the proteins evaluated, had different expression patterns in the tumor samples, the most prominent changes in expression were found for MRP-1. The exact clinical implications of these changes in expression and their relevance to the resistance of these tumors to chemotherapy requires further investigation. The finding of different expression profiles for the multidrug resistance proteins in the original WT's and their xenografts suggests that the results of animal cancer models may be difficult to interpret.

A constitutional translocation t(1;17(p36.2;q11.2 in a neuroblastoma patient disrupts the human NBPF1 and ACCN1 genes.

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Karl Vandepoele

Full Text Available The human 1p36 region is deleted in many different types of tumors, and so it probably harbors one or more tumor suppressor genes. In a Belgian neuroblastoma patient, a constitutional balanced translocation t(1;17(p36.2;q11.2 may have led to the development of the tumor by disrupting or activating a gene. Here, we report the cloning of both translocation breakpoints and the identification of a novel gene that is disrupted by this translocation. This gene, named NBPF1 for Neuroblastoma BreakPoint Family member 1, belongs to a recently described gene family encoding highly similar proteins, the functions of which are unknown. The translocation truncates NBPF1 and gives rise to two chimeric transcripts of NBPF1 sequences fused to sequences derived from chromosome 17. On chromosome 17, the translocation disrupts one of the isoforms of ACCN1, a potential glioma tumor suppressor gene. Expression of the NBPF family in neuroblastoma cell lines is highly variable, but it is decreased in cell lines that have a deletion of chromosome 1p. More importantly, expression profiling of the NBPF1 gene showed that its expression is significantly lower in cell lines with heterozygous NBPF1 loss than in cell lines with a normal 1p chromosome. Meta-analysis of the expression of NBPF and ACCN1 in neuroblastoma tumors indicates a role for the NBPF genes and for ACCN1 in tumor aggressiveness. Additionally, DLD1 cells with inducible NBPF1 expression showed a marked decrease of clonal growth in a soft agar assay. The disruption of both NBPF1 and ACCN1 genes in this neuroblastoma patient indicates that these genes might suppress development of neuroblastoma and possibly other tumor types.

Methylation of the RASSF1A, RARβ2, and SEMA3B genes in epithelial breast and ovarian tumors, and in patients with polyneoplasia

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T. P. Kazubskaya

2012-01-01

Full Text Available The methylation status of the tumor suppressor genes RASSF1A, RARβ2, and SEMA3B was studied in the samples of cancer and its histologically normal tissue of the breast and ovaries. The high rate of abnormal methylation of the CpG islet in the RASSF1A, RARβ2, and SEMA3B genes was found in the tumors of the breast (78% (32/41, 46% (26/56, and 35% (22/65, respectively and ovaries 73% (33/45, 30% (15/50, and 50% (25/51. Hypermethylation in the CpG islets belonging to the RASSF1A and RARβ2 genes was first ascertained in 90% of the patients with polyneoplasms involving the breast and ovaries. Abnormal methylation of the promotor region of the RASSF1A gene was shown to be detectable in preclinical-stage and anaplasia-degree breast and ovarian cancer. There was a correlation of the rate of methylation in the promoter regions of the RARβ2 and SEMA3B genes with clinical-stage and anaplasia-degree breast and ovarian cancer. Analysis of gene methylation in biological fluids provides considerable opportunity to use methylation of DNA as a marker in clinical practice.

PPB | What is the DICER1 gene?

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DICER1 is a gene that manages the function of other genes. Inherited changes in DICER1 can result in a variety of tumors, including pleuropulmonary blastoma (PPB). The PPB DICER1 Syndrome Study ‹an observational clinical research study is enrolling children with PPB and their families.

Real-time PCR analysis of genes encoding tumor antigens in esophageal tumors and a cancer vaccine

NARCIS (Netherlands)

Weinert, Brian T.; Krishnadath, Kausilia K.; Milano, Francesca; Pedersen, Ayako W.; Claesson, Mogens H.; Zocca, Mai-Britt

2009-01-01

Tumor antigens are the primary target of therapeutic cancer vaccines. We set out to define and compare the expression pattern of tumor antigen genes in esophagus carcinoma biopsies and in an allogeneic tumor lysate-based cancer vaccine, MelCancerVac. Cells used for vaccine production were treated

Alterations of tumor suppressor genes (Rb, p16, p27 and p53) and an increased FDG uptake in lung cancer

International Nuclear Information System (INIS)

Sasaki, Masayuki; Sugio, Kenji; Kuwabara, Yasuo

2003-01-01

The FDG uptake in lung cancer is considered to reflect the degree of malignancy, while alterations of some tumor suppressor genes are considered to be related to the malignant biological behavior of tumors. The aim of this study is to examine the relationship between FDG-PET and alterations in the tumor suppression genes of lung cancer. We examined 28 patients with primary lung cancer who underwent FDG-PET before surgery consisting of 17 patients with adenocarcinoma, 10 with squamous cell carcinoma and 1 with large cell carcinoma. The FDG-PET findings were evaluated based on the standardized uptake value (SUV). Alterations in the tumor suppressor genes, Rb, p16, p27 and p53, were evaluated immunohistochemically. The FDG uptake in lung cancer with alteration in each tumor suppressor gene tended to be higher than in those genes without alterations, although the differences were not significant. In 15 tumors with alterations in either tumor suppressor genes, the FDG uptake was 6.83±3.21. On the other hand, the mean FDG uptake was 1.95 in 2 tumors without alterations in any genes. The difference in the FDG uptake between the 2 groups was statistically significant (p<0.001). In conclusion, the presence of abnormalities in the tumor suppressor genes, which results in an accelerated cell proliferation, is thus considered to increase the FDG uptake in lung cancer. (author)

p53 and PTEN/MMAC1/TEP1 gene therapy of human prostate PC-3 carcinoma xenograft, using transferrin-facilitated lipofection gene delivery strategy.

Science.gov (United States)

Seki, Masafumi; Iwakawa, Jun; Cheng, Helen; Cheng, Pi-Wan

2002-04-10

We previously reported that supplementation of a cationic liposome with transferrin (Tf) greatly enhanced lipofection efficiency (P.-W. Cheng, Hum. Gene Ther. 1996;7:275-282). In this study, we examined the efficacy of p53 and PTEN tumor suppressor gene therapy in a mouse xenograft model of human prostate PC-3 carcinoma cells, using a vector consisting of dimyristoyloxypropyl-3-dimethylhydroxyethyl ammonium bromide (DMRIE)-cholesterol (DC) and Tf. When the volume of the tumors grown subcutaneously in athymic nude mice reached 50-60 mm(3), three intratumoral injections of the following four formulations were performed during week 1 and then during week 3: (1) saline, (2) DC + Tf + pCMVlacZ, (3) DC + Tf + pCMVPTEN, and (4) DC + Tf + pCMVp53 (standard formulation). There was no significant difference in tumor volume and survival between group 1 and group 2 animals. As compared with group 1 controls, group 3 animals had slower tumor growth during the first 3 weeks but thereafter their tumor growth rate was similar to that of the controls. By day 2 posttreatment, group 4 animals had significantly lower tumor volume relative to initial tumor volume as well as controls at the comparable time point. Also, animals treated with p53 survived longer. Treatment with DC, Tf, pCMVp53, DC + pCMVp53, or Tf + pCMVp53 had no effect on tumor volume or survival. Expression of p53 protein and apoptosis were detected in tumors treated with the standard formulation, thus associating p53 protein expression and apoptosis with efficacy. However, p53 protein was expressed in only a fraction of the tumor cells, suggesting a role for bystander effects in the efficacy of p53 gene therapy. We conclude that intratumoral gene delivery by a nonviral vector consisting of a cationic liposome and Tf can achieve efficacious p53 gene therapy of prostate cancer.

The Quest for the 1p36 Tumor Suppressor

Science.gov (United States)

Bagchi, Anindya; Mills, Alea A.

2010-01-01

Genomic analyses of late-stage human cancers have uncovered deletions encompassing 1p36, thereby providing an extensive body of literature supporting the idea that a potent tumor suppressor resides in this interval. Although a number of genes have been proposed as 1p36 candidate tumor suppressors, convincing evidence that their encoded products protect from cancer has been scanty. A recent functional study identified CHD5 as a novel tumor suppressor mapping to 1p36. Here we discuss evidence supporting CHD5’s tumor suppressive role. Together, these findings suggest that strategies designed to enhance CHD5 activity could provide novel approaches for treating a broad range of human malignancies. PMID:18413720

Effect of strain on evolution of dynamic recrystallization in Nb-1 wt%Zr-0.1 wt%C alloy at 1500 and 1600 °C

Energy Technology Data Exchange (ETDEWEB)

Behera, A.N. [Mechanical Metallurgy Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Homi Bhabha National Institute, Anushakti Nagar, Mumbai 400094 (India); Kapoor, R., E-mail: rkapoor@barc.gov.in [Mechanical Metallurgy Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Homi Bhabha National Institute, Anushakti Nagar, Mumbai 400094 (India); Paul, B. [Materials Processing & Corrosion Engineering Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Chakravartty, J.K. [Mechanical Metallurgy Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

2017-04-15

Uniaxial compression tests were carried out on Nb-1 wt%Zr-0.1 wt%C alloy at temperature of 1500 and 1600 °C and strain rate of 0.1 s{sup −1} to study the evolution of dynamic recrystallization with strain. Electron back scatter diffraction was used to quantify the microstructural evolution. Nb-1Zr-0.1C alloy showed a necklace structure at a strain of 0.9 when deformed at 1500 °C and at strain of 0.6 when deformed at 1600 °C, both at strain rate of 0.1 s{sup −1}. This suggested the occurrence of dynamic recrystallization. At 1500 °C and strain of 0.9 the local average misorientation and the grain orientation spread was low confirming the presence of dynamic recrystallization at this deformation condition. At both 1500 and 1600 °C and all measured strains the recrystallized grains had a strong fiber component of <001>. - Highlights: • Necklace formation of dynamically recrystallized grains occurred at strain of 0.6 and 0.9 for 1500 and 1600 °C, respectively. • Equiaxed microstructures were seen with increase in strain for both 1500 and 1600 °C. • At large strains the predominant recrystallized texture evolved to <001> pole.

Acute lymphoblastic leukemia mimicking Wilms tumor at presentation.

Science.gov (United States)

Singh, Amitabh; Mandal, Anirban; Guru, Vijay; Seth, Rachna

2016-09-01

Acute lymphoblastic leukemia (ALL), the commonest malignancy of childhood, is known to manifest with a myriad of atypical presentations. Nephromegaly is a rare presentation of childhood ALL with hepatic mass being even rarer. We present a 3 year-old child with unilateral renal mass and hepatic mass lesion with normal blood counts, initially suspected to have metastatic Wilms tumor based on clinical, radiological and WT1 positivity on immunocytochemistry of renal mass. He was later diagnosed as ALL with peripheral blood flowcytometry and bone marrow examination. Renomegaly at presentation of acute leukemia is not necessarily due to leukemic infiltration and rarely leads to renal impairment. The radiological differential of such a renal mass includes both benign and malignant entities including metastasis. Over-expression of WT1 mRNA has been found in a number of solid tumors and hematological malignancies and is far from being diagnostic of Wilms tumor. Again, a small number of children with acute leukemia may have a deceptively normal complete blood count at presentation. Though, initial all (clinical, radiological, hematological, and immunocytological) parameters pointed towards a diagnosis of Wilms tumor in our case, the subsequent development of thrombocytopenia and lymphocytic leukocytosis prompted further investigation and final diagnosis of ALL. WT1 positivity is a known phenomenon in childhood ALL and undifferentiated lymphoblasts may be positive for WT1 and negative for Leucocyte common antigen. Acute leukemia with renal and hepatic mass with normal blood counts at presentation is a diagnostic challenge.

Gene expression profiles of cell adhesion molecules, matrix metalloproteinases and their tissue inhibitors in canine oral tumors.

Science.gov (United States)

Pisamai, Sirinun; Rungsipipat, Anudep; Kalpravidh, Chanin; Suriyaphol, Gunnaporn

2017-08-01

Perturbation of cell adhesion can be essential for tumor cell invasion and metastasis, but the current knowledge on the gene expression of molecules that mediate cell adhesion in canine oral tumors is limited. The present study aimed to investigate changes in the gene expression of cell adhesion molecules (E-cadherin or CDH1, syndecan 1 or SDC1, NECTIN2 and NECTIN4), matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs), in canine oral tumors, including benign tumors, oral melanoma (OM) and non-tonsillar oral squamous cell carcinoma (OSCC), by quantitative real-time reverse transcription PCR. When compared with the normal gingival controls, decreased CDH1, SDC1 and NECTIN4 expression levels were observed in OSCC and OM, reflecting a possible role as cell adhesion molecules and tumor suppressors in canine oral cancers in contrast to the upregulation of MMP2 expression. Downregulated MMP7 was specifically revealed in the OM group. In the late-stage OM, the positive correlation of MMP7 and CDH1 expression was noticed as well as that of SDC1 and NECTIN4. Enhanced TIMP1 expression was shown in all tumor groups with prominent expression in the benign tumors and the early-stage OM. MMP14 expression was notable in the early-stage OM. Higher MMP9 and TIMP1 expression was observed in the acanthomatous ameloblastoma. In conclusion, this study revealed that the altered expression of cell adhesion molecules, MMP7 and MMP2 was correlated with clinicopathologic features in canine oral cancers whereas TIMP1 and MMP14 expression was probably associated with early-stage tumors; therefore, these genes might serve as molecular markers for canine oral tumors. Copyright © 2017 Elsevier Ltd. All rights reserved.

RET is a potential tumor suppressor gene in colorectal cancer

Science.gov (United States)

Luo, Yanxin; Tsuchiya, Karen D.; Park, Dong Il; Fausel, Rebecca; Kanngurn, Samornmas; Welcsh, Piri; Dzieciatkowski, Slavomir; Wang, Jianping; Grady, William M.

2012-01-01

Cancer arises as the consequence of mutations and epigenetic alterations that activate oncogenes and inactivate tumor suppressor genes. Through a genome-wide screen for methylated genes in colon neoplasms, we identified aberrantly methylated RET in colorectal cancer. RET, a transmembrane receptor tyrosine kinase and a receptor for the GDNF-family ligands, was one of the first oncogenes to be identified and has been shown to be an oncogene in thyroid cancer and pheochromocytoma. However, unexpectedly, we found RET is methylated in 27% of colon adenomas and in 63% of colorectal cancers, and now provide evidence that RET has tumor suppressor activity in colon cancer. The aberrant methylation of RET correlates with decreased RET expression, whereas the restoration of RET in colorectal cancer cell lines results in apoptosis. Furthermore, in support of a tumor suppressor function of RET, mutant RET has also been found in primary colorectal cancer. We now show that these mutations inactivate RET, which is consistent with RET being a tumor suppressor gene in the colon. These findings suggest that the aberrant methylation of RET and the mutational inactivation of RET promote colorectal cancer formation and that RET can serve as a tumor suppressor gene in the colon. Moreover, the increased frequency of methylated RET in colon cancers compared to adenomas suggests RET inactivation is involved in the progression of colon adenomas to cancer. PMID:22751117

Synergistic gene and drug tumor therapy using a chimeric peptide.

Science.gov (United States)

Han, Kai; Chen, Si; Chen, Wei-Hai; Lei, Qi; Liu, Yun; Zhuo, Ren-Xi; Zhang, Xian-Zheng

2013-06-01

Co-delivery of gene and drug for synergistic therapy has provided a promising strategy to cure devastating diseases. Here, an amphiphilic chimeric peptide (Fmoc)2KH7-TAT with pH-responsibility for gene and drug delivery was designed and fabricated. As a drug carrier, the micelles self-assembled from the peptide exhibited a much faster doxorubicin (DOX) release rate at pH 5.0 than that at pH 7.4. As a non-viral gene vector, (Fmoc)(2)KH(7)-TAT peptide could satisfactorily mediate transfection of pGL-3 reporter plasmid with or without the existence of serum in both 293T and HeLa cell-lines. Besides, the endosome escape capability of peptide/DNA complexes was investigated by confocal laser scanning microscopy (CLSM). To evaluate the co-delivery efficiency and the synergistic anti-tumor effect of gene and drug, p53 plasmid and DOX were simultaneously loaded in the peptide micelles to form micelleplexes during the self-assembly of the peptide. Cellular uptake and intracellular delivery of gene and drug were studied by CLSM and flow cytometry respectively. And p53 protein expression was determined via Western blot analysis. The in vitro cytotoxicity and in vivo tumor inhibition effect were also studied. Results suggest that the co-delivery of gene and drug from peptide micelles resulted in effective cell growth inhibition in vitro and significant tumor growth restraining in vivo. The chimeric peptide-based gene and drug co-delivery system will find great potential for tumor therapy. Copyright © 2013 Elsevier Ltd. All rights reserved.

Alternative polyadenylation of tumor suppressor genes in small intestinal neuroendocrine tumors

DEFF Research Database (Denmark)

Rehfeld, Anders Aagaard; Plass, Mireya; Døssing, Kristina

2014-01-01

The tumorigenesis of small intestinal neuroendocrine tumors (SI-NETs) is poorly understood. Recent studies have associated alternative polyadenylation (APA) with proliferation, cell transformation, and cancer. Polyadenylation is the process in which the pre-messenger RNA is cleaved at a polyA site...... and a polyA tail is added. Genes with two or more polyA sites can undergo APA. This produces two or more distinct mRNA isoforms with different 3' untranslated regions. Additionally, APA can also produce mRNAs containing different 3'-terminal coding regions. Therefore, APA alters both the repertoire...... and the expression level of proteins. Here, we used high-throughput sequencing data to map polyA sites and characterize polyadenylation genome-wide in three SI-NETs and a reference sample. In the tumors, 16 genes showed significant changes of APA pattern, which lead to either the 3' truncation of mRNA coding regions...

The potential for tumor suppressor gene therapy in head and neck cancer.

Science.gov (United States)

Birkeland, Andrew C; Ludwig, Megan L; Spector, Matthew E; Brenner, J Chad

2016-01-01

Head and neck squamous cell carcinoma remains a highly morbid and fatal disease. Importantly, genomic sequencing of head and neck cancers has identified frequent mutations in tumor suppressor genes. While targeted therapeutics increasingly are being investigated in head and neck cancer, the majority of these agents are against overactive/overexpressed oncogenes. Therapy to restore lost tumor suppressor gene function remains a key and under-addressed niche in trials for head and neck cancer. Recent advances in gene editing have captured the interest of both the scientific community and the public. As our technology for gene editing and gene expression modulation improves, addressing lost tumor suppressor gene function in head and neck cancers is becoming a reality. This review will summarize new techniques, challenges to implementation, future directions, and ethical ramifications of gene therapy in head and neck cancer.

Tumor-specific apoptotic gene targeting overcomes radiation resistance in esophageal adenocarcinoma

International Nuclear Information System (INIS)

Chang, Joe Y.; Zhang Xiaochun; Komaki, Ritsuko; Cheung, Rex; Fang Bingliang

2006-01-01

Purpose: To overcome radiation resistance in esophageal adenocarcinoma by tumor-specific apoptotic gene targeting using tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). Methods and Materials: Adenoviral vector Ad/TRAIL-F/RGD with a tumor-specific human telomerase reverse transcription promoter was used to transfer TRAIL gene to human esophageal adenocarcinoma and normal human lung fibroblastic cells (NHLF). Activation of apoptosis was analyzed by Western blot, fluorescent activated cell sorting, and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate labeling (TUNEL) assay. A human esophageal adenocarcinoma mouse model was treated with intratumoral injections of Ad/TRAIL-F/RGD plus local radiotherapy. Results: The combination of Ad/TRAIL-F/RGD and radiotherapy increased the cell-killing effect in all esophageal adenocarcinoma cell lines but not in NHLF cells. This combination also significantly reduced clonogenic formation (p < 0.05) and increased sub-G1 deoxyribonucleic acid accumulation in cancer cells (p < 0.05). Activation of apoptosis by Ad/TRAIL-F/RGD plus radiotherapy was demonstrated by activation of caspase-9, caspase-8, and caspase-3 and cleaved poly (adenosine diphosphate-ribose) polymerase in vitro and TUNEL assay in vivo. Combined Ad/TRAIL-F/RGD and radiotherapy dramatically inhibited tumor growth and prolonged mean survival in the esophageal adenocarcinoma model to 31.6 days from 16.7 days for radiotherapy alone and 21.5 days for Ad/TRAIL-F/RGD alone (p < 0.05). Conclusions: The combination of tumor-specific TRAIL gene targeting and radiotherapy enhances the effect of suppressing esophageal adenocarcinoma growth and prolonging survival

HRAS1-selected chromosome transfer generates markers that colocalize aniridia- and genitourinary dysplasia-associated translocation breakpoints and the Wilms tumor gene within band 11p13.

OpenAIRE

Porteous, D J; Bickmore, W; Christie, S; Boyd, P A; Cranston, G; Fletcher, J M; Gosden, J R; Rout, D; Seawright, A; Simola, K O

1987-01-01

We show that chromosome-mediated gene transfer can provide an enriched source of DNA markers for predetermined, subchromosomal regions of the human genome. Forty-four human DNA recombinants isolated from a HRAS1-selected chromosome-mediated gene transformant map exclusively to chromosome 11, with several sublocalizing to the Wilms tumor region at 11p13. We present a detailed molecular map of the deletion chromosomes 11 from five WAGR (Wilms tumor/aniridia/genitourinary abnormalities/mental re...

Electrochemical corrosion of Pb-1 wt% Sn and Pb-2.5 wt% Sn alloys for lead-acid battery applications

Energy Technology Data Exchange (ETDEWEB)

Osorio, Wislei R.; Peixoto, Leandro C.; Garcia, Amauri [Department of Materials Engineering, State University of Campinas - UNICAMP, PO Box 612, 13083-970 Campinas, SP (Brazil)

2009-12-01

The aim of this study was to compare the electrochemical corrosion behavior of as-cast Pb-1 wt% Sn and Pb-2.5 wt% Sn alloy samples in a 0.5 M H{sub 2}SO{sub 4} solution at 25 C. A water-cooled unidirectional solidification system was used to obtain the as-cast samples. Electrochemical impedance spectroscopy (EIS) diagrams, potentiodynamic polarization curves and an equivalent circuit analysis were used to evaluate the electrochemical corrosion response. It was found that a coarse cellular array has a better electrochemical corrosion resistance than fine cells. The pre-programming of microstructure cell size of Pb-Sn alloys can be used as an alternative way to produce as-cast components of lead-acid batteries with higher corrosion resistance associated with environmental and economical aspects. (author)

Codon 61 mutations in the c-Harvey-ras gene in mouse skin tumors induced by 7,12-dimethylbenz[a]anthracene plus okadaic acid class tumor promoters.

Science.gov (United States)

Fujiki, H; Suganuma, M; Yoshizawa, S; Kanazawa, H; Sugimura, T; Manam, S; Kahn, S M; Jiang, W; Hoshina, S; Weinstein, I B

1989-01-01

Three okadaic acid class tumor promoters, okadaic acid, dinophysistoxin-1, and calyculin A, have potent tumor-promoting activity in two-stage carcinogenesis experiments on mouse skin. DNA isolated from tumors induced by 7,12-dimethylbenz[a]anthracene (DMBA) and each of these tumor promoters revealed the same mutation at the second nucleotide of codon 61 (CAA----CTA) in the c-Ha-ras gene, determined by the polymerase chain reaction procedure and DNA sequencing. Three potent 12-O-tetradecanoylphorbol-13-acetate (TPA)-type tumor promoters, TPA, teleocidin, and aplysiatoxin, showed the same effects. These results provide strong evidence that this mutation in the c-Ha-ras gene is due to a direct effect of DMBA rather than a selective effect of specific tumor promoters.

MUC1-C activates polycomb repressive complexes and downregulates tumor suppressor genes in human cancer cells.

Science.gov (United States)

Rajabi, Hasan; Hiraki, Masayuki; Kufe, Donald

2018-04-01

The PRC2 and PRC1 complexes are aberrantly expressed in human cancers and have been linked to decreases in patient survival. MUC1-C is an oncoprotein that is also overexpressed in diverse human cancers and is associated with a poor prognosis. Recent studies have supported a previously unreported function for MUC1-C in activating PRC2 and PRC1 in cancer cells. In the regulation of PRC2, MUC1-C (i) drives transcription of the EZH2 gene, (ii) binds directly to EZH2, and (iii) enhances occupancy of EZH2 on target gene promoters with an increase in H3K27 trimethylation. Regarding PRC1, which is recruited to PRC2 sites in the hierarchical model, MUC1-C induces BMI1 transcription, forms a complex with BMI1, and promotes H2A ubiquitylation. MUC1-C thereby contributes to the integration of PRC2 and PRC1-mediated repression of tumor suppressor genes, such as CDH1, CDKN2A, PTEN and BRCA1. Like PRC2 and PRC1, MUC1-C is associated with the epithelial-mesenchymal transition (EMT) program, cancer stem cell (CSC) state, and acquisition of anticancer drug resistance. In concert with these observations, targeting MUC1-C downregulates EZH2 and BMI1, inhibits EMT and the CSC state, and reverses drug resistance. These findings emphasize the significance of MUC1-C as a therapeutic target for inhibiting aberrant PRC function and reprogramming the epigenome in human cancers.

Focal versus diffuse anaplasia in Wilms tumor--new definitions with prognostic significance: a report from the National Wilms Tumor Study Group.

Science.gov (United States)

Faria, P; Beckwith, J B; Mishra, K; Zuppan, C; Weeks, D A; Breslow, N; Green, D M

1996-08-01

Anaplasia, defined by the presence of extreme nuclear and mitotic atypia, is a potent marker of adverse prognosis in Wilms tumor (WT). Anaplastic WT cells apparently have increased resistance to therapy rather than increased aggressiveness. The distribution of anaplasia should therefore have critical prognostic relevance. The original definitions for focal anaplasia (FA) and diffuse anaplasia (DA) were based on quantitative rather than topographical criteria and lacked prognostic significance. A new definition was developed based on the distribution of anaplastic changes within the tumor: FA applies only to tumors with anaplasia confined to one or a few discrete loci within the primary tumor, with no anaplasia or marked nuclear atypia elsewhere. This revised definition was evaluated in 165 cases with anaplastic WT entered on the third and fourth National Wilms Tumor Study. Only three relapses and one death occurred among 39 cases with FA, regardless of tumor stage, a result comparable to that for nonanaplastic WT. Eight children with metastases at diagnosis and FA in the primary tumor were alive and free of relapse; 22 of 23 children with stage IV DA WT died of tumor. This new definition reinforces the importance of carefully documenting the exact site from which each tumor section is obtained.

Contribution of MLH1 constitutional methylation for Lynch syndrome diagnosis in patients with tumor MLH1 downregulation.

Science.gov (United States)

Pinto, Diana; Pinto, Carla; Guerra, Joana; Pinheiro, Manuela; Santos, Rui; Vedeld, Hege Marie; Yohannes, Zeremariam; Peixoto, Ana; Santos, Catarina; Pinto, Pedro; Lopes, Paula; Lothe, Ragnhild; Lind, Guro Elisabeth; Henrique, Rui; Teixeira, Manuel R

2018-02-01

Constitutional epimutation of the two major mismatch repair genes, MLH1 and MSH2, has been identified as an alternative mechanism that predisposes to the development of Lynch syndrome. In the present work, we aimed to investigate the prevalence of MLH1 constitutional methylation in colorectal cancer (CRC) patients with abnormal expression of the MLH1 protein in their tumors. In a series of 38 patients who met clinical criteria for Lynch syndrome genetic testing, with loss of MLH1 expression in the tumor and with no germline mutations in the MLH1 gene (35/38) or with tumors presenting the BRAF p.Val600Glu mutation (3/38), we screened for constitutional methylation of the MLH1 gene promoter using methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) in various biological samples. We found four (4/38; 10.5%) patients with constitutional methylation in the MLH1 gene promoter. RNA studies demonstrated decreased MLH1 expression in the cases with constitutional methylation when compared with controls. We could infer the mosaic nature of MLH1 constitutional hypermethylation in tissues originated from different embryonic germ layers, and in one family we could show that it occurred de novo. We conclude that constitutional MLH1 methylation occurs in a significant proportion of patients who have loss of MLH1 protein expression in their tumors and no MLH1 pathogenic germline mutation. Furthermore, we provide evidence that MLH1 constitutional hypermethylation is the molecular mechanism behind about 3% of Lynch syndrome families diagnosed in our institution, especially in patients with early onset or multiple primary tumors without significant family history. © 2018 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Trojan horse at cellular level for tumor gene therapies.

Science.gov (United States)

Collet, Guillaume; Grillon, Catherine; Nadim, Mahdi; Kieda, Claudine

2013-08-10

Among innovative strategies developed for cancer treatments, gene therapies stand of great interest despite their well-known limitations in targeting, delivery, toxicity or stability. The success of any given gene-therapy is highly dependent on the carrier efficiency. New approaches are often revisiting the mythic trojan horse concept to carry therapeutic nucleic acid, i.e. DNAs, RNAs or small interfering RNAs, to pathologic tumor site. Recent investigations are focusing on engineering carrying modalities to overtake the above limitations bringing new promise to cancer patients. This review describes recent advances and perspectives for gene therapies devoted to tumor treatment, taking advantage of available knowledge in biotechnology and medicine. Copyright © 2013 Elsevier B.V. All rights reserved.

Hypoxia-Inducible Regulation of a Prodrug-Activating Enzyme for Tumor-Specific Gene Therapy

Directory of Open Access Journals (Sweden)

Toru Shibata

2002-01-01

Full Text Available Previous studies have suggested that tumor hypoxia could be exploited for cancer gene therapy. Using hypoxia-responsive elements derived from the human vascular endothelial growth factor gene, we have generated vectors expressing a bacterial nitroreductase. (20NTR gene that can activate the anticancer prodrug CB1954. Stable transfectants of human HT1080 tumor cells with hypoxia-inducible vectors were established with G418 selection. Hypoxic induction of NTR protein correlated with increased sensitivity to in vitro exposure of HT 1080 cells to the prodrug. Growth delay assays were performed with established tumor xenografts derived from the same cells to detect the in vivo efficacy of CB1954 conversion to its cytotoxic form. Significant antitumor effects were achieved with intraperitoneal injections of CB1954 both in tumors that express NTR constitutively or with a hypoxia-inducible promoter. In addition, respiration of 10% O2 increased tumor hypoxia in vivo and enhanced the antitumor effects. Taken together, these results demonstrate that hypoxia-inducible vectors may be useful for tumor-selective gene therapy, although the problem of delivery of the vector to the tumors, particularly to the hypoxic cells in the tumors, is not addressed by these studies.

Genes Associated With Prognosis After Surgery For Malignant Pleural Mesothelioma Promote Tumor Cell Survival In Vitro

International Nuclear Information System (INIS)

Gordon, Gavin J; Bueno, Raphael; Sugarbaker, David J

2011-01-01

Mesothelioma is an aggressive neoplasm with few effective treatments, one being cytoreductive surgery. We previously described a test, based on differential expression levels of four genes, to predict clinical outcome in prospectively consented mesothelioma patients after surgery. In this study, we determined whether any of these four genes could be linked to a cancer relevant phenotype. We conducted a high-throughput RNA inhibition screen to knockdown gene expression levels of the four genes comprising the test (ARHGDIA, COBLL1, PKM2, TM4SF1) in both a human lung-derived normal and a tumor cell line using three different small inhibitory RNA molecules per gene. Successful knockdown was confirmed using quantitative RT-PCR. Detection of statistically significant changes in apoptosis and mitosis was performed using immunological assays and quantified using video-assisted microscopy at a single time-point. Changes in nuclear shape, size, and numbers were used to provide additional support of initial findings. Each experiment was conducted in triplicate. Specificity was assured by requiring that at least 2 different siRNAs produced the observed change in each cell line/time-point/gene/assay combination. Knockdown of ARHGDIA, COBLL1, and TM4SF1 resulted in 2- to 4-fold increased levels of apoptosis in normal cells (ARHGDIA only) and tumor cells (all three genes). No statistically significant changes were observed in apoptosis after knockdown of PKM2 or for mitosis after knockdown of any gene. We provide evidence that ARHGDIA, COBLL1, and TM4SF1 are negative regulators of apoptosis in cultured tumor cells. These genes, and their related intracellular signaling pathways, may represent potential therapeutic targets in mesothelioma

TP53, STK11 and EGFR Mutations Predict Tumor Immune Profile and the Response to anti-PD-1 in Lung Adenocarcinoma.

Science.gov (United States)

Biton, Jerome; Mansuet-Lupo, Audrey; Pécuchet, Nicolas; Alifano, Marco; Ouakrim, Hanane; Arrondeau, Jennifer; Boudou-Rouquette, Pascaline; Goldwasser, Francois; Leroy, Karen; Goc, Jeremy; Wislez, Marie; Germain, Claire; Laurent-Puig, Pierre; Dieu-Nosjean, Marie-Caroline; Cremer, Isabelle; Herbst, Ronald; Blons, Hélène F; Damotte, Diane

2018-05-15

By unlocking anti-tumor immunity, antibodies targeting programmed cell death 1 (PD-1) exhibit impressive clinical results in non-small cell lung cancer, underlining the strong interactions between tumor and immune cells. However, factors that can robustly predict long-lasting responses are still needed. We performed in depth immune profiling of lung adenocarcinoma using an integrative analysis based on immunohistochemistry, flow-cytometry and transcriptomic data. Tumor mutational status was investigated using next-generation sequencing. The response to PD-1 blockers was analyzed from a prospective cohort according to tumor mutational profiles and to PD-L1 expression, and a public clinical database was used to validate the results obtained. We showed that distinct combinations of STK11 , EGFR and TP53 mutations, were major determinants of the tumor immune profile (TIP) and of the expression of PD-L1 by malignant cells. Indeed, the presence of TP53 mutations without co-occurring STK11 or EGFR alterations ( TP53 -mut/ STK11 - EGFR -WT), independently of KRAS mutations, identified the group of tumors with the highest CD8 T cell density and PD-L1 expression. In this tumor subtype, pathways related to T cell chemotaxis, immune cell cytotoxicity, and antigen processing were up-regulated. Finally, a prolonged progression-free survival (PFS: HR=0.32; 95% CI, 0.16-0.63, p <0.001) was observed in anti-PD-1 treated patients harboring TP53 -mut/ STK11 - EGFR -WT tumors. This clinical benefit was even more remarkable in patients with associated strong PD-L1 expression. Our study reveals that different combinations of TP53 , EGFR and STK11 mutations , together with PD-L1 expression by tumor cells, represent robust parameters to identify best responders to PD-1 blockade. Copyright ©2018, American Association for Cancer Research.

Regional and temporal differences in gene expression of LH(BETA)T(AG) retinoblastoma tumors.

Science.gov (United States)

Houston, Samuel K; Pina, Yolanda; Clarke, Jennifer; Koru-Sengul, Tulay; Scott, William K; Nathanson, Lubov; Schefler, Amy C; Murray, Timothy G

2011-07-23

The purpose of this study was to evaluate by microarray the hypothesis that LH(BETA)T(AG) retinoblastoma tumors exhibit regional and temporal variations in gene expression. LH(BETA)T(AG) mice aged 12, 16, and 20 weeks were euthanatized (n = 9). Specimens were taken from five tumor areas (apex, anterior lateral, center, base, and posterior lateral). Samples were hybridized to gene microarrays. The data were preprocessed and analyzed, and genes with a P 2.5 were considered to be differentially expressed. Differentially expressed genes were analyzed for overlap with known networks by using pathway analysis tools. There were significant temporal (P regional differences in gene expression for LH(BETA)T(AG) retinoblastoma tumors. At P 2.5, there were significant changes in gene expression of 190 genes apically, 84 genes anterolaterally, 126 genes posteriorly, 56 genes centrally, and 134 genes at the base. Differentially expressed genes overlapped with known networks, with significant involvement in regulation of cellular proliferation and growth, response to oxygen levels and hypoxia, regulation of cellular processes, cellular signaling cascades, and angiogenesis. There are significant temporal and regional variations in the LH(BETA)T(AG) retinoblastoma model. Differentially expressed genes overlap with key pathways that may play pivotal roles in murine retinoblastoma development. These findings suggest the mechanisms involved in tumor growth and progression in murine retinoblastoma tumors and identify pathways for analysis at a functional level, to determine significance in human retinoblastoma. Microarray analysis of LH(BETA)T(AG) retinal tumors showed significant regional and temporal variations in gene expression, including dysregulation of genes involved in hypoxic responses and angiogenesis.

Loss of heterozygosity of CDKN2A (p16INK4a) and RB1 tumor suppressor genes in testicular germ cell tumors

International Nuclear Information System (INIS)

Vladusic, Tomislav; Hrascan, Reno; Pecina-Slaus, Nives; Vrhovac, Ivana; Gamulin, Marija; Franekic, Jasna; Kruslin, Bozo

2010-01-01

Testicular germ cell tumors (TGCTs) are the most frequent malignances in young adult men. The two main histological forms, seminomas and nonseminomas, differ biologically and clinically. pRB protein and its immediate upstream regulator p16INK4a are involved in the RB pathway which is deregulated in most TGCTs. The objective of this study was to evaluate the occurrence of loss of heterozygosity (LOH) of the CDKN2A (p16INK4a) and RB1 tumor suppressor genes in TGCTs. Forty TGCTs (18 seminomas and 22 nonseminomas) were analyzed by polymerase chain reaction using the restriction fragment length polymorphism or the nucleotide repeat polymorphism method. LOH of the CDKN2A was found in two (6%) out of 34 (85%) informative cases of our total TGCT sample. The observed changes were assigned to two (11%) nonseminomas out of 18 (82%) informative samples. Furthermore, LOH of the RB1 was detected in two (6%) out of 34 (85%) informative cases of our total TGCT sample. Once again, the observed changes were assigned to two (10.5%) nonseminomas out of 19 (86%) informative samples. Both LOHs of the CDKN2A were found in nonseminomas with a yolk sac tumor component, and both LOHs of the RB1 were found in nonseminomas with an embryonal carcinoma component. The higher incidence of observed LOH in nonseminomas may provide a clue to their invasive behavior

A expressão de genes reparadores do DNA nos tumores sincrônicos de câncer colorretal esporádico DNA repair gene expression in synchronic tumors of sporadic colorectal cancer

Directory of Open Access Journals (Sweden)

Igor Proscurshim

2007-03-01

Full Text Available RACIONAL: Um dos mecanismos genéticos presentes em aproximadamente 80% dos pacientes com síndrome hereditária não-polipóide do câncer colorretal (HNPCC são os defeitos nos genes reparadores de DNA, como o MSH2, MSH6 e MLH1, onde os tumores sincrônicos são relativamente freqüentes. Já no câncer colorretal esporádico as lesões sincrônicas são raras. OBJETIVO: Verificar se o mesmo mecanismo genético presente no HNPCC está presente no câncer colorretal esporádico que apresentam com lesões sincrônicas. MÉTODOS: Foram incluídos no estudo todos os pacientes com câncer colorretal sincrônico não HNPCC. Imunoistoquímica com anticorpos para MSH2,MSH6, e MLH1 foi realizada para cada tumor. RESULTADOS: Todos os pacientes apresentaram expressão normal de MSH2 e MLH1. O único gene com imunoexpressão alterada foi o MSH6. CONCLUSÃO: Possivelmente outro mecanismo genético seja responsável pelo surgimento de dois tumores sincrônicos no câncer colorretal esporádico.BACKGROUND: Mismatch repair genes (such as MSH2, MLH1 and MSH6 mutations are present in over 80% of hereditary non-polyposis colorectal cancer (HNPCC tumors, which frequently exhibit synchronous lesions. Sporadic colorectal cancer is rarely associated with synchronous lesions. AIM: To investigate the role of mismatch repair gene mutation in synchronous sporadic colorectal cancer. METHODS: Patients with sporadic synchronous colorectal adenocarcinomas were included in the study. Immunohistochemistry was performed using MSH2, MLH1 and MSH6 antibodies. RESULTS: All patients had two synchoronous lesions. None of them had altered MSH2 or MLH1 expression. One patient had altered MSH6 expression in both tumors. CONCLUSION: Possibly, other molecular mechanisms are involved in carcinogenesis of sporadic synchronous colorectal cancer.

Simultaneous down-regulation of tumor suppressor genes RBSP3/CTDSPL, NPRL2/G21 and RASSF1A in primary non-small cell lung cancer

International Nuclear Information System (INIS)

Senchenko, Vera N; Zabarovsky, Eugene R; Anedchenko, Ekaterina A; Kondratieva, Tatiana T; Krasnov, George S; Dmitriev, Alexei A; Zabarovska, Veronika I; Pavlova, Tatiana V; Kashuba, Vladimir I; Lerman, Michael I

2010-01-01

The short arm of human chromosome 3 is involved in the development of many cancers including lung cancer. Three bona fide lung cancer tumor suppressor genes namely RBSP3 (AP20 region),NPRL2 and RASSF1A (LUCA region) were identified in the 3p21.3 region. We have shown previously that homozygous deletions in AP20 and LUCA sub-regions often occurred in the same tumor (P < 10 -6 ). We estimated the quantity of RBSP3, NPRL2, RASSF1A, GAPDH, RPN1 mRNA and RBSP3 DNA copy number in 59 primary non-small cell lung cancers, including 41 squamous cell and 18 adenocarcinomas by real-time reverse transcription-polymerase chain reaction based on TaqMan technology and relative quantification. We evaluated the relationship between mRNA level and clinicopathologic characteristics in non-small cell lung cancer. A significant expression decrease (≥2) was found for all three genes early in tumor development: in 85% of cases for RBSP3; 73% for NPRL2 and 67% for RASSF1A (P < 0.001), more strongly pronounced in squamous cell than in adenocarcinomas. Strong suppression of both, NPRL2 and RBSP3 was seen in 100% of cases already at Stage I of squamous cell carcinomas. Deregulation of RASSF1A correlated with tumor progression of squamous cell (P = 0.196) and adenocarcinomas (P < 0.05). Most likely, genetic and epigenetic mechanisms might be responsible for transcriptional inactivation of RBSP3 in non-small cell lung cancers as promoter methylation of RBSP3 according to NotI microarrays data was detected in 80% of squamous cell and in 38% of adenocarcinomas. With NotI microarrays we tested how often LUCA (NPRL2, RASSF1A) and AP20 (RBSP3) regions were deleted or methylated in the same tumor sample and found that this occured in 39% of all studied samples (P < 0.05). Our data support the hypothesis that these TSG are involved in tumorigenesis of NSCLC. Both genetic and epigenetic mechanisms contribute to down-regulation of these three genes representing two tumor suppressor clusters in 3p21

Reduced rates of gene loss, gene silencing, and gene mutation in Dnmt1-deficient embryonic stem cells

NARCIS (Netherlands)

Chan, M.F.; van Amerongen, R.; Nijjar, T.; Cuppen, E.; Jones, P.A.; Laird, P.W.

2001-01-01

Tumor suppressor gene inactivation is a crucial event in oncogenesis. Gene inactivation mechanisms include events resulting in loss of heterozygosity (LOH), gene mutation, and transcriptional silencing. The contribution of each of these different pathways varies among tumor suppressor genes and by

Irradiation promotes Akt-targeting therapeutic gene delivery to the tumor vasculature

International Nuclear Information System (INIS)

Sonveaux, Pierre; Frerart, Francoise; Bouzin, Caroline; Brouet, Agnes; Wever, Julie de; Jordan, Benedicte F.; Gallez, Bernard; Feron, Olivier

2007-01-01

Purpose: To determine whether radiation-induced increases in nitric oxide (NO) production can influence tumor blood flow and improve delivery of Akt-targeting therapeutic DNA lipocomplexes to the tumor. Methods and Materials: The contribution of NO to the endothelial response to radiation was identified using NO synthase (NOS) inhibitors and endothelial NOS (eNOS)-deficient mice. Reporter-encoding plasmids complexed with cationic lipids were used to document the tumor vascular specificity and the efficacy of in vivo lipofection after irradiation. A dominant-negative Akt gene construct was used to evaluate the facilitating effects of radiotherapy on the therapeutic transgene delivery. Results: The abundance of eNOS protein was increased in both irradiated tumor microvessels and endothelial cells, leading to a stimulation of NO release and an associated increase in tumor blood flow. Transgene expression was subsequently improved in the irradiated vs. nonirradiated tumor vasculature. This effect was not apparent in eNOS-deficient mice and could not be reproduced in irradiated cultured endothelial cells. Finally, we combined low-dose radiotherapy with a dominant-negative Akt gene construct and documented synergistic antitumor effects. Conclusions: This study offers a new rationale to combine radiotherapy with gene therapy, by directly exploiting the stimulatory effects of radiation on NO production by tumor endothelial cells. The preferential expression of the transgene in the tumor microvasculature underscores the potential of such an adjuvant strategy to limit the angiogenic response of irradiated tumors

Experimental determination of the H2O + 15 wt% NaCl and H2O + 25 wt% NaCl liquidi to 1.4 GPa

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Valenti, P.; Schmidt, C.

2009-12-01

The binary H2O+NaCl is one of the most important model systems for chloridic fluids in many geologic environments such as the Earth’s crust, upper mantle, and subducting slabs, and is also applicable to extraterrestrial icy planetary bodies (e.g., Manning 2004, Zolensky et al., 1999). The knowledge on phase equilibria and PVTx properties of this system is still fragmentary at high pressures, e.g., very little has been reported on liquidi at compositions Daniel 2008). In this study, we investigated the liquidus of 15 and 25 wt% NaCl solutions at pressures up to 1.4 GPa. The experiments were performed using a hydrothermal diamond-anvil cell (Bassett et al. 1993) modified for Raman spectroscopy and accurate temperature measurements. A quartz chip, halite, and water were loaded into the sample chamber, which also contained a small trapped air bubble (10 vol%) when it was sealed. The actual salinity was then determined from measurement of the vapor-saturated liquidus temperature. The sample chamber was then compressed until the bubble disappeared. After freezing, phase transitions occurring with increasing temperature were observed optically, and the pressure was determined from the frequency shift of the 464 cm-1 Raman line of quartz (Schmidt and Ziemann 2000). The sample chamber was then compressed further, and the experiment was repeated at various bulk densities until a pressure of ~1.4 GPa was attained. At some conditions, Raman spectra were acquired for identification of the phase assemblage. The solution always crystallized to a single phase upon cooling above ~0.15 GPa at 25 wt% NaCl and above ~1 GPa at 15 wt% NaCl. Raman spectra in the OH stretching region indicate that this phase contains or is a NaCl hydrate other than hydrohalite, probably in solid solution with ice. Melting of this phase produced liquid and hydrohalite and/or ice VI. Ice VI was the last solid that dissolved upon heating, between 1100 MPa, 3 °C and 1370 MPa, 17 °C for 15 wt% NaCl and at

Radiation-associated breast tumors display a distinct gene expression profile

DEFF Research Database (Denmark)

Broeks, Annegien; Braaf, Linde M; Wessels, Lodewyk F A

2010-01-01

PURPOSE: Women who received irradiation for Hodgkin's lymphoma have a strong increased risk for developing breast cancer. Approximately 90% of the breast cancers in these patients can be attributed to their radiation treatment, rendering such series extremely useful to determine whether a common...... radiation-associated cause underlies the carcinogenic process. METHODS AND MATERIALS: In this study we used gene expression profiling technology to assess gene expression changes in radiation-associated breast tumors compared with a set of control breast tumors of women unexposed to radiation, diagnosed...... at the same age. RNA was obtained from fresh frozen tissue samples from 22 patients who developed breast cancer after Hodgkin's lymphoma (BfHL) and from 20 control breast tumors. RESULTS: Unsupervised hierarchical clustering of the profile data resulted in a clustering of the radiation-associated tumors...

Changes in oil content of transgenic soybeans expressing the yeast SLC1 gene.

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Rao, Suryadevara S; Hildebrand, David

2009-10-01

The wild type (Wt) and mutant form of yeast (sphingolipid compensation) genes, SLC1 and SLC1-1, have been shown to have lysophosphatidic acid acyltransferase (LPAT) activities (Nageic et al. in J Biol Chem 269:22156-22163, 1993). Expression of these LPAT genes was reported to increase oil content in transgenic Arabidopsis and Brassica napus. It is of interest to determine if the TAG content increase would also be seen in soybeans. Therefore, the wild type SLC1 was expressed in soybean somatic embryos under the control of seed specific phaseolin promoter. Some transgenic somatic embryos and in both T2 and T3 transgenic seeds showed higher oil contents. Compared to controls, the average increase in triglyceride values went up by 1.5% in transgenic somatic embryos. A maximum of 3.2% increase in seed oil content was observed in a T3 line. Expression of the yeast Wt LPAT gene did not alter the fatty acid composition of the seed oil.

Type I collagen gene suppresses tumor growth and invasion of malignant human glioma cells

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Miyata Teruo

2007-06-01

Full Text Available Abstract Background Invasion is a hallmark of a malignant tumor, such as a glioma, and the progression is followed by the interaction of tumor cells with an extracellular matrix (ECM. This study examined the role of type I collagen in the invasion of the malignant human glioma cell line T98G by the introduction of the human collagen type I α1 (HCOL1A1 gene. Results The cells overexpressing HCOL1A1 were in a cluster, whereas the control cells were scattered. Overexpression of HCOL1A1 significantly suppressed the motility and invasion of the tumor cells. The glioma cell growth was markedly inhibited in vitro and in vivo by the overexpression of HCOL1A1; in particular, tumorigenicity completely regressed in nude mice. Furthermore, the HCOL1A1 gene induced apoptosis in glioma cells. Conclusion These results indicate that HCOL1A1 have a suppressive biological function in glioma progression and that the introduction of HCOL1A1 provides the basis of a novel therapeutic approach for the treatment of malignant human glioma.

Anomalous precipitation hardening in Al-(1 wt%)Cu thin films

NARCIS (Netherlands)

Bergers, L. J. C.; De Hosson, J. Th. M.; Geers, M. G. D.; Hoefnagels, J. P. M.

2018-01-01

This paper concentrates on the precipitation hardening of Al-(1 wt%)Cu thin films. It is shown that in contrast to bulk, the well-known approach of precipitation hardening in confined systems like thin layers and thin films does not operate in the conventional way. This work analyses and discusses

Andrographolide promotes vincristine-induced SK-NEP-1 tumor cell death via PI3K-AKT-p53 signaling pathway

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Zhang M

2016-09-01

Full Text Available Mingsheng Zhang, Enda Xue, Wei Shao Department of Pediatric Surgery, Liaocheng People’s Hospital, Liaocheng, Shandong Province, People’s Republic of China Background: Nephroblastoma (Wilms’ tumor [WT] is the most common malignant renal cancer in children. Although the outcome of WT has significantly improved as a result of the combination of surgery, chemotherapy, and radiotherapy; in some cases WT results in severe complications. Thus, novel strategies that would decrease treatment burden are required. The aim of the current study was to investigate the synergistic antitumor effect of andrographolide (AND in combination with vincristine (VCR on WT cells.Methods: Cell Counting Kit-8 assay was used to investigate the synergistic antiproliferation effect of AND and/or VCR on SK-NEP-1 cells in vitro. Meanwhile, SK-NEP-1 xenografts were used to detect the antitumor effect in vivo. Apoptosis and autophagy were then detected by Annexin V, monodansylcadaverine staining. Finally, the underlying signaling transduction was determined with Western blotting.Results: The combination of AND with VCR significantly suppressed SK-NEP-1 cell proliferation in vitro and inhibited xenograft tumor growth in vivo, compared with AND or VCR treatment alone. In addition, the synergistic antitumor effect of AND on the cells was due to an increased apoptosis, not autophagy. Moreover, PI3K-AKT-p53 signaling pathway was involved in the process of combination treatment, which was confirmed when a selective AKT activator was applied.Conclusion: The combination of AND with VCR has a strong synergistic antitumor effect on WT via PI3K-AKT-p53 signaling pathway, thereby representing a potential treatment for WT in the near future. Keywords: andrographolide, vincristine, p53, drug combination

Microstructure and adhesion strength of Sn-9Zn-1.5Ag-xBi (x = 0 wt% and 2 wt%)/Cu after electrochemical polarization in a 3.5 wt% NaCl solution

Energy Technology Data Exchange (ETDEWEB)

Li, W.-L. [Department of Mechanical Engineering, National Kaohsiung University of Applied Sciences, 415 Chien-Kung Road, Kaohsiung 80782, Taiwan (China); Institute of Nanotechnology and Microsystems Engineering, National Cheng Kung University, 1 Ta-Hsueh Road, Tainan 70101, Taiwan (China); Chen, Y.-R.; Chang, K.-M. [Department of Mechanical Engineering, National Kaohsiung University of Applied Sciences, 415 Chien-Kung Road, Kaohsiung 80782, Taiwan (China); Liu, C.-Y.; Hon, M.-H. [Department of Materials Science and Engineering, National Cheng Kung University, 1 Ta-Hsueh Road, Tainan 70101, Taiwan (China); Wang, M.-C. [Faculty of Fragrance and Cosmetics, Kaohsiung Medical University, 100 Shihchuan 1st Road, Kaohsiung 80728, Taiwan (China)], E-mail: mcwang@kmu.edu.tw

2008-08-11

The microstructure and adhesion strength of the Sn-9Zn-1.5Ag-xBi (x = 0 wt% and 2 wt%)/Cu interface after electrochemical polarization have been studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and pull-off testing. The equilibrium potentials of Sn-9Zn-1.5Ag/Cu and Sn-9Zn-1.5Ag-2Bi/Cu are -1.31 V{sub sce} and -1.22 V{sub sce}, respectively, indicating that Sn-9Zn-1.5Ag-2Bi/Cu has a better corrosion resistance than that of Sn-9Zn-1.5Ag/Cu. The intermetallic compounds of Cu{sub 6}Sn{sub 5}, Cu{sub 5}Zn{sub 8} and Ag{sub 3}Sn are formed at the soldered interface between the Sn-9Zn-1.5Ag-xBi solder alloy and the Cu substrate. The scallop-shaped Cu{sub 6}Sn{sub 5} is close to the Cu substrate and the scallop-shaped Cu{sub 5}Zn{sub 8} is found at the interface in the solder matrix after soldering at 250 deg. C for 10 s. The corrosion products are ZnCl{sub 2}, SnCl{sub 2} and ZnO. On the other hand, pits are also formed on the surface of both solder alloys. The interfacial adhesion strength of the Sn-9Zn-1.5Ag/Cu and Sn-9Zn-1.5Ag-2Bi/Cu decreases from 8.27 {+-} 0.56 MPa and 12.67 {+-} 0.45 MPa to 4.78 {+-} 0.45 MPa and 8.14 {+-} 0.38 MPa, respectively, after electrochemical polarization in a 3.5 wt% NaCl solution. The fracture path of the Sn-9Zn-1.5Ag-2Bi/Cu is along the solder alloy/ZnO and solder/Cu{sub 6}Sn{sub 5} interfaces.

Gene alterations in radiation-induced F344 rat lung tumors

International Nuclear Information System (INIS)

Kelly, G.; Hahn, F.F.

1994-01-01

The p53 tumor suppressor gene is frequently altered in all major histopathologic types of human lung tumors. Reported p53 mutations include base substitutions, allelic loss, rearrangements, and deletions. Point mutations resulting in base substitutions are clustered within a highly conserved region of the gene encoding exons 508, and mutations in this region substantially extend the half-life of the p53 protein. In addition to its prominent importance in lung carcinogenesis, the p53 gene plays a critical role in the cellular response to genetic damage caused by radiation. Specifically, the protein product of p53 induces a pause or block at the G 1 to S boundary of the cell cycle following radiation-caused DNA damage. This G 1 block may allow the cell time to repair the damaged DNA prior to replication. Cells lacking a functional p53 protein fail to pause for repair and consequently accumulate mutations in the genome at an accelerated rate. p53 has also been implicated as a controlling factor in apoptosis or in programmed cell death induced by DNA-damaging agents, such as ionizing radiation. The p53 gene is mutated in approximately 50% of squamous cell carcinomas from uranium miners who inhaled high doses of radon daughters. The purpose of the present study was to determine if a similar percentage of squamous cell carcinomas with p53 mutations developed in the lungs of rats exposed to aerosols of 239 PuO 2

Rrp1b, a new candidate susceptibility gene for breast cancer progression and metastasis.

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Nigel P S Crawford

2007-11-01

Full Text Available A novel candidate metastasis modifier, ribosomal RNA processing 1 homolog B (Rrp1b, was identified through two independent approaches. First, yeast two-hybrid, immunoprecipitation, and functional assays demonstrated a physical and functional interaction between Rrp1b and the previous identified metastasis modifier Sipa1. In parallel, using mouse and human metastasis gene expression data it was observed that extracellular matrix (ECM genes are common components of metastasis predictive signatures, suggesting that ECM genes are either important markers or causal factors in metastasis. To investigate the relationship between ECM genes and poor prognosis in breast cancer, expression quantitative trait locus analysis of polyoma middle-T transgene-induced mammary tumor was performed. ECM gene expression was found to be consistently associated with Rrp1b expression. In vitro expression of Rrp1b significantly altered ECM gene expression, tumor growth, and dissemination in metastasis assays. Furthermore, a gene signature induced by ectopic expression of Rrp1b in tumor cells predicted survival in a human breast cancer gene expression dataset. Finally, constitutional polymorphism within RRP1B was found to be significantly associated with tumor progression in two independent breast cancer cohorts. These data suggest that RRP1B may be a novel susceptibility gene for breast cancer progression and metastasis.

Genes Associated With Prognosis After Surgery For Malignant Pleural Mesothelioma Promote Tumor Cell Survival In Vitro

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Sugarbaker David J

2011-05-01

Full Text Available Abstract Background Mesothelioma is an aggressive neoplasm with few effective treatments, one being cytoreductive surgery. We previously described a test, based on differential expression levels of four genes, to predict clinical outcome in prospectively consented mesothelioma patients after surgery. In this study, we determined whether any of these four genes could be linked to a cancer relevant phenotype. Methods We conducted a high-throughput RNA inhibition screen to knockdown gene expression levels of the four genes comprising the test (ARHGDIA, COBLL1, PKM2, TM4SF1 in both a human lung-derived normal and a tumor cell line using three different small inhibitory RNA molecules per gene. Successful knockdown was confirmed using quantitative RT-PCR. Detection of statistically significant changes in apoptosis and mitosis was performed using immunological assays and quantified using video-assisted microscopy at a single time-point. Changes in nuclear shape, size, and numbers were used to provide additional support of initial findings. Each experiment was conducted in triplicate. Specificity was assured by requiring that at least 2 different siRNAs produced the observed change in each cell line/time-point/gene/assay combination. Results Knockdown of ARHGDIA, COBLL1, and TM4SF1 resulted in 2- to 4-fold increased levels of apoptosis in normal cells (ARHGDIA only and tumor cells (all three genes. No statistically significant changes were observed in apoptosis after knockdown of PKM2 or for mitosis after knockdown of any gene. Conclusions We provide evidence that ARHGDIA, COBLL1, and TM4SF1 are negative regulators of apoptosis in cultured tumor cells. These genes, and their related intracellular signaling pathways, may represent potential therapeutic targets in mesothelioma.

MEPE, a new gene expressed in bone marrow and tumors causing osteomalacia.

Science.gov (United States)

Rowe, P S; de Zoysa, P A; Dong, R; Wang, H R; White, K E; Econs, M J; Oudet, C L

2000-07-01

Oncogenic hypophosphatemic osteomalacia (OHO) is characterized by a renal phosphate leak, hypophosphatemia, low-serum calcitriol (1,25-vitamin-D3), and abnormalities in skeletal mineralization. Resection of OHO tumors results in remission of the symptoms, and there is evidence that a circulating phosphaturic factor plays a role in the bone disease. This paper describes the characterization and cloning of a gene that is a candidate for the tumor-secreted phosphaturic factor. This new gene has been named MEPE (matrix extracellular phosphoglycoprotein) and has major similarities to a group of bone-tooth mineral matrix phospho-glycoproteins (osteopontin (OPN; HGMW-approved symbol SPP1), dentin sialo phosphoprotein (DSPP), dentin matrix protein 1 (DMP1), bone sialoprotein II (IBSP), and bone morphogenetic proteins (BMP). All the proteins including MEPE contain RGD sequence motifs that are proposed to be essential for integrin-receptor interactions. Of further interest is the finding that MEPE, OPN, DSPP, DMP1, IBSP, and BMP3 all map to a defined region in chromosome 4q. Refined mapping localizes MEPE to 4q21.1 between ESTs D4S2785 (WI-6336) and D4S2844 (WI-3770). MEPE is 525 residues in length with a short N-terminal signal peptide. High-level expression of MEPE mRNA occurred in all four OHO tumors screened. Three of 11 non-OHO tumors screened contained trace levels of MEPE expression (detected only after RT-PCR and Southern 32P analysis). Normal tissue expression was found in bone marrow and brain with very-low-level expression found in lung, kidney, and human placenta. Evidence is also presented for the tumor secretion of clusterin (HGMW-approved symbol CLU) and its possible role as a cytotoxic factor in one of the OHO patients described.

Three-dimensional tumor spheroids for in vitro analysis of bacteria as gene delivery vectors in tumor therapy.

Science.gov (United States)

Osswald, Annika; Sun, Zhongke; Grimm, Verena; Ampem, Grace; Riegel, Karin; Westendorf, Astrid M; Sommergruber, Wolfgang; Otte, Kerstin; Dürre, Peter; Riedel, Christian U

2015-12-12

Several studies in animal models demonstrated that obligate and facultative anaerobic bacteria of the genera Bifidobacterium, Salmonella, or Clostridium specifically colonize solid tumors. Consequently, these and other bacteria are discussed as live vectors to deliver therapeutic genes to inhibit tumor growth. Therapeutic approaches for cancer treatment using anaerobic bacteria have been investigated in different mouse models. In the present study, solid three-dimensional (3D) multicellular tumor spheroids (MCTS) of the colorectal adenocarcinoma cell line HT-29 were generated and tested for their potential to study prodrug-converting enzyme therapies using bacterial vectors in vitro. HT-29 MCTS resembled solid tumors displaying all relevant features with an outer zone of proliferating cells and hypoxic and apoptotic regions in the core. Upon incubation with HT-29 MCTS, Bifidobacterium bifidum S17 and Salmonella typhimurium YB1 selectively localized, survived and replicated in hypoxic areas inside MCTS. Furthermore, spores of the obligate anaerobe Clostridium sporogenes germinated in these hypoxic areas. To further evaluate the potential of MCTS to investigate therapeutic approaches using bacteria as gene delivery vectors, recombinant bifidobacteria expressing prodrug-converting enzymes were used. Expression of a secreted cytosine deaminase in combination with 5-fluorocytosine had no effect on growth of MCTS due to an intrinsic resistance of HT-29 cells to 5-fluorouracil, i.e. the converted drug. However, a combination of the prodrug CB1954 and a strain expressing a secreted chromate reductase effectively inhibited MCTS growth. Collectively, the presented results indicate that MCTS are a suitable and reliable model to investigate live bacteria as gene delivery vectors for cancer therapy in vitro.

Liver tumor formation by a mutant retinoblastoma protein in the transgenic mice is caused by an upregulation of c-Myc target genes

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Wang, Bo; Hikosaka, Keisuke; Sultana, Nishat; Sharkar, Mohammad Tofael Kabir [Department of Biochemistry, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan); Noritake, Hidenao [Department of Biochemistry, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan); Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan); Kimura, Wataru; Wu, Yi-Xin [Department of Biochemistry, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan); Kobayashi, Yoshimasa [Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan); Uezato, Tadayoshi [Department of Biochemistry, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan); Miura, Naoyuki, E-mail: nmiura@hama-med.ac.jp [Department of Biochemistry, Hamamatsu University School of Medicine, 1-20-1 Handa-yama, Higashi-ku, Hamamatsu 431-3192 (Japan)

2012-01-06

Highlights: Black-Right-Pointing-Pointer Fifty percent of the mutant Rb transgenic mice produced liver tumors. Black-Right-Pointing-Pointer In the tumor, Foxm1, Skp2, Bmi1 and AP-1 mRNAs were up-regulated. Black-Right-Pointing-Pointer No increase in expression of the Myc-target genes was observed in the non-tumorous liver. Black-Right-Pointing-Pointer Tumor formation depends on up-regulation of the Myc-target genes. -- Abstract: The retinoblastoma (Rb) tumor suppressor encodes a nuclear phosphoprotein that regulates cellular proliferation, apoptosis and differentiation. In order to adapt itself to these biological functions, Rb is subjected to modification cycle, phosphorylation and dephosphorylation. To directly determine the effect of phosphorylation-resistant Rb on liver development and function, we generated transgenic mice expressing phosphorylation-resistant human mutant Rb (mt-Rb) under the control of the rat hepatocyte nuclear factor-1 gene promoter/enhancer. Expression of mt-Rb in the liver resulted in macroscopic neoplastic nodules (adenomas) with {approx}50% incidence within 15 months old. Interestingly, quantitative reverse transcriptase-PCR analysis showed that c-Myc was up-regulated in the liver of mt-Rb transgenic mice irrespective of having tumor tissues or no tumor. In tumor tissues, several c-Myc target genes, Foxm1, c-Jun, c-Fos, Bmi1 and Skp2, were also up-regulated dramatically. We determined whether mt-Rb activated the Myc promoter in the HTP9 cells and demonstrated that mt-Rb acted as an inhibitor of wild-type Rb-induced repression on the Myc promoter. Our results suggest that continued upregulation of c-Myc target genes promotes the liver tumor formation after about 1 year of age.

Tumor growth reduction is regulated at the gene level in Walker 256 tumor-bearing rats supplemented with fish oil rich in EPA and DHA

Energy Technology Data Exchange (ETDEWEB)

Borghetti, G.; Yamazaki, R.K.; Coelho, I.; Pequito, D.C.T.; Schiessel, D.L.; Kryczyk, M.; Mamus, R.; Naliwaiko, K.; Fernandes, L.C. [Departamento de Fisiologia, Setor de Ciências Biológicas, Universidade Federal do Paraná, Curitiba, PR (Brazil)

2013-08-23

We investigated the effect of fish oil (FO) supplementation on tumor growth, cyclooxygenase 2 (COX-2), peroxisome proliferator-activated receptor gamma (PPARγ), and RelA gene and protein expression in Walker 256 tumor-bearing rats. Male Wistar rats (70 days old) were fed with regular chow (group W) or chow supplemented with 1 g/kg body weight FO daily (group WFO) until they reached 100 days of age. Both groups were then inoculated with a suspension of Walker 256 ascitic tumor cells (3×10{sup 7} cells/mL). After 14 days the rats were killed, total RNA was isolated from the tumor tissue, and relative mRNA expression was measured using the 2{sup -ΔΔCT} method. FO significantly decreased tumor growth (W=13.18±1.58 vs WFO=5.40±0.88 g, P<0.05). FO supplementation also resulted in a significant decrease in COX-2 (W=100.1±1.62 vs WFO=59.39±5.53, P<0.001) and PPARγ (W=100.4±1.04 vs WFO=88.22±1.46, P<0.05) protein expression. Relative mRNA expression was W=1.06±0.022 vs WFO=0.31±0.04 (P<0.001) for COX-2, W=1.08±0.02 vs WFO=0.52±0.08 (P<0.001) for PPARγ, and W=1.04±0.02 vs WFO=0.82±0.04 (P<0.05) for RelA. FO reduced tumor growth by attenuating inflammatory gene expression associated with carcinogenesis.

Cholesterol-Containing Nuclease-Resistant siRNA Accumulates in Tumors in a Carrier-free Mode and Silences MDR1 Gene

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Ivan V. Chernikov

2017-03-01

Full Text Available Chemical modifications are an effective way to improve the therapeutic properties of small interfering RNAs (siRNAs, making them more resistant to degradation in serum and ensuring their delivery to target cells and tissues. Here, we studied the carrier-free biodistribution and biological activity of a nuclease-resistant anti-MDR1 cholesterol-siRNA conjugate in healthy and tumor-bearing severe combined immune deficiency (SCID mice. The attachment of cholesterol to siRNA provided its efficient accumulation in the liver and in tumors, and reduced its retention in the kidneys after intravenous and intraperitoneal injection. The major part of cholesterol-siRNA after intramuscular and subcutaneous injections remained in the injection place. Confocal microscopy data demonstrated that cholesterol-siRNA spread deep in the tissue and was present in the cytoplasm of almost all the liver and tumor cells. The reduction of P-glycoprotein level in human KB-8-5 xenograft overexpressing the MDR1 gene by 60% was observed at days 5–6 after injection. Then, its initial level recovered by the eighth day. The data showed that, regardless of the mode of administration (intravenous, intraperitoneal, or peritumoral, cholesterol-siMDR efficiently reduced the P-glycoprotein level in tumors. The designed anti-MDR1 conjugate has potential as an adjuvant therapeutic for the reversal of multiple drug resistance of cancer cells.

Significance of TP53 Mutation in Wilms Tumors with Diffuse Anaplasia: A Report from the Children’s Oncology Group

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Ooms, Ariadne H.A.G.; Gadd, Samantha; Gerhard, Daniela S.; Smith, Malcolm A.; Guidry Auvil, Jaime M.; Meerzaman, Daoud; Chen, Qing-Rong; Hsu, Chih Hao; Yan, Chunhua; Nguyen, Cu; Hu, Ying; Ma, Yussanne; Zong, Zusheng; Mungall, Andrew J.; Moore, Richard A.; Marra, Marco A.; Huff, Vicki; Dome, Jeffrey S.; Chi, Yueh-Yun; Tian, Jing; Geller, James I.; Mullighan, Charles G.; Ma, Jing; Wheeler, David A.; Hampton, Oliver A.; Walz, Amy L.; van den Heuvel-Eibrink, Marry M.; de Krijger, Ronald R.; Ross, Nicole; Gastier-Foster, Julie M.; Perlman, Elizabeth J.

2016-01-01

Purpose To investigate the role and significance of TP53 mutation in diffusely anaplastic Wilms tumor (DAWT). Experimental Design All DAWTs registered on National Wilms Tumor Study-5 (n=118) with available samples were analyzed for TP53 mutations and copy loss. Integrative genomic analysis was performed on 39 selected DAWTs. Results Following analysis of a single random sample, 57 DAWT (48%) demonstrated TP53 mutations, 13(11%) copy loss without mutation, and 48(41%) lacked both (defined as TP53-wildtype (wt)). Patients with Stage III/IV TP53-wt DAWTs (but not those with Stage I/II disease) had significantly lower relapse and death rates than those with TP53 abnormalities. In-depth analysis of a subset of 39 DAWT showed 7(18%) to be TP53-wt: these demonstrated gene expression evidence of an active p53 pathway. Retrospective pathology review of TP53-wt DAWT revealed no or very low volume of anaplasia in 6/7 tumors. When samples from TP53-wt tumors known to contain anaplasia histologically were available, abnormal p53 protein accumulation was observed by immunohistochemistry. Conclusion These data support the key role of TP53 loss in the development of anaplasia in WT, and support its significant clinical impact in patients with residual anaplastic tumor following surgery. These data also suggest that most DAWTs will show evidence of TP53 mutation when samples selected for the presence of anaplasia are analyzed. This suggests that modifications of the current criteria to also consider volume of anaplasia and documentation of TP53 aberrations may better reflect the risk of relapse and death and enable optimization of therapeutic stratification. PMID:27702824

Hypoxia in Tumor Angiogenesis and Metastasis: Evaluation of VEGF and MMP Over-expression and Down-Regulation of HIF-1alpha with RNAi in Hypoxic Tumor Cells

Science.gov (United States)

Shah, Shruti

Background: As tumor mass grows beyond a few millimeters in diameter, the angiogenic "switch" is turned on leading to recruitment of blood vessels from surrounding artery and veins. However, the tumor mass is poorly perfused and there are pockets of hypoxia or lower oxygen concentrations relative to normal tissue. Hypoxia-inducing factor-1a (HIF-1a), a transcription factor, is activated when the oxygen concentration is low. Upon activation of HIF-1a, a number of other genes also turn on that allows the tumor to become more aggressive and resistant to therapy. Purpose: The main objectives of this study were to evaluate the effect of hypoxia-induced HIF-1a followed by over-expression of angiogenic and metastatic markers in tumor cells and down-regulation of HIF-1a using nanoparticle-delivered RNA interference therapy. Methods: Human ovarian (SKOV3) and breast (MDA-MB-231) adenocarcinoma cells were incubated under normoxic and hypoxic conditions. Following hypoxia treatment of the cells, HIF-1α, vascular endothelial growth factor (VEGF), matrix metalloproteinase 2 (MMP-2), and MMP-9 expression was analyzed qualitatively and quantitatively. For intracellular delivery of HIF-1a gene silencing small interfering RNA (siRNA), type B gelatin nanoparticles were fabricated using the solvent displacement method and the surface was modified with poly(ethylene glycol) (PEG, Mol. wt. 2kDa). Cellular uptake and distribution of the nanoparticles was observed with Cy3-siRNA loaded, FITC-conjugated gelatin nanoparticles. Cytotoxicity of the nanoparticle formulations was evaluated in both the cell lines. siRNA was transfected in the gelatin nanoparticles under hypoxic conditions. Total cellular protein and RNA were extracted for analysis of HIF1a, VEGF, MMP-2 and MMP-9 expression. Results: MDA-MB-231 and SKOV3 cells show increased expression of HIF1a under hypoxic conditions compared to baseline levels at normoxic conditions. ELISA and western blots of VEGF, MMP-2 and MMP-9 appear to

THE EFFECTS OF Jatropha curcas L SEED EXTRACT IN REGULATION EXPRESSION TUMOR MARKER OF TGF- β1 GENE

Directory of Open Access Journals (Sweden)

Endah Wulandari

2017-04-01

Full Text Available The role of TGF-β1 is known as the main immunosuppresor associated with tumor, but on the other opinion, it is associated with proliferation and tumor invasion. The increase and decrease of the secretion of TGF-β is to regulate the proliferation, differentiation, and death of various cell types. Now we all know the extract of Jatropha curcas L seed serves as antitumor. Allegedly, it can regulate the expression of TGF-β1 in control of cell number. The purpose of this study is to determine the effects of Jatropha seeds to the regulation of gene expression of TGF-β1 as a tumor marker. The method is performed by giving a dose groups the extract of jatropha seed (0, 5, 25, 50, 250 mg/BB in mice. Then measurement of mRNA expression (RT-PCR, the protein of TGF-β1 levels (ELISA, and qualitative observations of liver histology were done. The expression of TGF-β1 mRNA is significantly 4.39 to 7.34 times higher than (ANOVA, p 0.05 than the control. Histological observation of liver showed the extract of jatropha seed induces damage nucleus of hepatocytes cell and sinusoidal. The effects extract of jatropha seed increased the level of TGF-β1 mRNA but not followed by increasing protein of TGF-β1 levels, and it was stimulated necrosis and apoptosis of hepatocytes cell.

Direct visualization of electroporation-assisted in vivo gene delivery to tumors using intravital microscopy – spatial and time dependent distribution

International Nuclear Information System (INIS)

Cemazar, Maja; Wilson, Ian; Dachs, Gabi U; Tozer, Gillian M; Sersa, Gregor

2004-01-01

Electroporation is currently receiving much attention as a way to increase drug and DNA delivery. Recent studies demonstrated the feasibility of electrogene therapy using a range of therapeutic genes for the treatment of experimental tumors. However, the transfection efficiency of electroporation-assisted DNA delivery is still low compared to viral methods and there is a clear need to optimize this approach. In order to optimize treatment, knowledge about spatial and time dependency of gene expression following delivery is of utmost importance in order to improve gene delivery. Intravital microscopy of tumors growing in dorsal skin fold window chambers is a useful method for monitoring gene transfection, since it allows non-invasive dynamic monitoring of gene expression in tumors in a live animal. Intravital microscopy was used to monitor real time spatial distribution of the green fluorescent protein (GFP) and time dependence of transfection efficiency in syngeneic P22 rat tumor model. DNA alone, liposome-DNA complexes and electroporation-assisted DNA delivery using two different sets of electric pulse parameters were compared. Electroporation-assisted DNA delivery using 8 pulses, 600 V/cm, 5 ms, 1 Hz was superior to other methods and resulted in 22% increase in fluorescence intensity in the tumors up to 6 days post-transfection, compared to the non-transfected area in granulation tissue. Functional GFP was detected within 5 h after transfection. Cells expressing GFP were detected throughout the tumor, but not in the surrounding tissue that was not exposed to electric pulses. Intravital microscopy was demonstrated to be a suitable method for monitoring time and spatial distribution of gene expression in experimental tumors and provided evidence that electroporation-assisted gene delivery using 8 pulses, 600 V/cm, 5 ms, 1 Hz is an effective method, resulting in early onset and homogenous distribution of gene expression in the syngeneic P22 rat tumor model

Mechanical Properties of 0.14wt%C – 0.56wt%Mn – 0.13wt%Si ...

African Journals Online (AJOL)

Effect of intercritical heat treatment on 0.14wt%C – 0.56wt%Mn – 0.13wt%Si structural steel has been investigated. Specimens for single quenching and those for double quenching were prepared for intercritical heat treatment. The heat treatment of the experimental steel was based on intercritical annealing in the ferrite + ...

Molecular characterization of Wilms tumor from a resource-constrained region of sub-Saharan Africa