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Hansel DE, Rahman A, House M, Ashfaq R, Berg K, Yeo CJ, Maitra A. Met proto-oncogene and insulin-like growth factor binding protein 3 overexpression correlates with metastatic ability in well-differentiated pancreatic endocrine neoplasms. Clin Cancer Res 2005; 10:6152-8. [PMID: 15448002 DOI: 10.1158/1078-0432.ccr-04-0285] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Pancreatic endocrine neoplasms are neoplastic proliferations of islet cells or islet cell precursors and are capable of secreting a variety of synthetic products, including insulin, glucagon, gastrin, and vasoactive intestinal peptide. The biological behavior of pancreatic endocrine neoplasms is often unpredictable, and there are few reliable histopathologic criteria reliably correlating with metastatic ability. We have used the Affymetrix U133 GeneChip set (HG_U133 A and B; Affymetrix; Santa Clara, CA) representing approximately 33,000 characterized transcripts to examine global gene expression profiles from well-differentiated nonmetastatic (n=5) and metastatic (n=7) pancreatic endocrine neoplasms to determine molecular markers that predict disease progression. Microarray hybridization data were normalized using the GeneLogic GeneExpress Software System to identify differentially up- and down-regulated genes in metastatic versus nonmetastatic pancreatic endocrine neoplasms. Using a 3-fold change in gene expression as a threshold, we have identified 65 overexpressed and 57 underexpressed genes in metastatic pancreatic endocrine neoplasms as compared with nonmetastatic pancreatic endocrine neoplasms. Several classes of genes, including growth factors and growth factor-related molecules (IGFBP1, IGFBP3, and MET), developmental factors (TBX3 and MEIS2), cytoskeletal factors (beta 1 tubulin and ACTN2), cholesterol homeostasis mediators (LRP5, SLC27A2, and RXRG), intracellular signaling pathway mediators (DYRK1A, PKIB, and AK2), methyltransferases (MGMT and GAMT), and DNA repair and regulatory molecules (CHEK1 and ZNF198), were identified as differentially over- or underexpressed via this method. Immunohistochemical validation of microarray data were performed for two overexpressed genes, namely, the met proto-oncogene (MET) and insulin-like growth factor binding protein 3 (IGFBP3) with tissue microarrays of nonmetastatic (n=24) and metastatic (n=15) pancreatic endocrine neoplasms. Increased expression of IGFBP3 was confirmed in metastatic versus nonmetastatic pancreatic endocrine neoplasms (12 of 15, 80% versus 10 of 24, 42%), as well as in lymph node (6 of 7, 86%) and liver (9 of 9, 100%) metastases. Similarly, overexpression of MET was confirmed in metastatic versus nonmetastatic pancreatic endocrine neoplasms (5 of 15, 33% versus 4 of 24, 17%), as well as in lymph node metastases (4 of 7, 57%) and liver metastases (5 of 9, 56%). The majority of genes that demonstrated altered expression has not been previously identified as differentially expressed in metastatic pancreatic endocrine neoplasm lesions and may therefore represent newly identified molecules in the progression of these lesions.
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Affiliation(s)
- Donna E Hansel
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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Chou CY, Lin YL, Huang YC, Sheu SY, Lin TH, Tsay HJ, Chang GG, Shiao MS. Structural variation in human apolipoprotein E3 and E4: secondary structure, tertiary structure, and size distribution. Biophys J 2004; 88:455-66. [PMID: 15475580 PMCID: PMC1305022 DOI: 10.1529/biophysj.104.046813] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Human apolipoprotein E (apoE) is a 299-amino-acid protein with a molecular weight of 34 kDa. The difference between the apoE3 and apoE4 isoforms is a single residue substitution involving a Cys-Arg replacement at residue 112. ApoE4 is positively associated with atherosclerosis and late-onset and sporadic Alzheimer's disease (AD). ApoE4 and its C-terminal truncated fragments have been found in the senile plaques and neurofibrillary tangles in the brain of AD patients. However, detail structural information regarding isoform and domain interaction remains poorly understood. We prepared full-length, N-, and C-terminal truncated apoE3 and apoE4 proteins and studied their structural variation. Sedimentation velocity and continuous size distribution analysis using analytical ultracentrifugation revealed apoE3(72-299) as consisting of a major species with a sedimentation coefficient of 5.9. ApoE4(72-299) showed a wider and more complicated species distribution. Both apoE3 and E4 N-terminal domain (1-191) existed with monomers as the major component together with some tetramer. The oligomerization and aggregation of apoE protein increased when the C-terminal domain (192-271) was incorporated. The structural influence of the C-terminal domain on apoE is to assist self-association with no significant isoform preference. Circular dichroism and fluorescence studies demonstrated that apoE4(72-299) possessed a more alpha-helical structure with more hydrophobic residue exposure. The structural variation of the N-terminal truncated apoE3 and apoE4 protein provides useful information that helps to explain the greater aggregation of the apoE4 isoform and thus has implication for the involvement of apoE4 in AD.
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Affiliation(s)
- Chi-Yuan Chou
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan; Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei 112, Taiwan; and Faculty of Life Sciences, Institute of Biochemistry, Institute of Neuroscience, and Structural Biology Program, National Yang-Ming University, Taipei 112, Taiwan
| | - Yi-Ling Lin
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan; Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei 112, Taiwan; and Faculty of Life Sciences, Institute of Biochemistry, Institute of Neuroscience, and Structural Biology Program, National Yang-Ming University, Taipei 112, Taiwan
| | - Yu-Chyi Huang
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan; Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei 112, Taiwan; and Faculty of Life Sciences, Institute of Biochemistry, Institute of Neuroscience, and Structural Biology Program, National Yang-Ming University, Taipei 112, Taiwan
| | - Sheh-Yi Sheu
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan; Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei 112, Taiwan; and Faculty of Life Sciences, Institute of Biochemistry, Institute of Neuroscience, and Structural Biology Program, National Yang-Ming University, Taipei 112, Taiwan
| | - Ta-Hsien Lin
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan; Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei 112, Taiwan; and Faculty of Life Sciences, Institute of Biochemistry, Institute of Neuroscience, and Structural Biology Program, National Yang-Ming University, Taipei 112, Taiwan
| | - Huey-Jen Tsay
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan; Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei 112, Taiwan; and Faculty of Life Sciences, Institute of Biochemistry, Institute of Neuroscience, and Structural Biology Program, National Yang-Ming University, Taipei 112, Taiwan
| | - Gu-Gang Chang
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan; Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei 112, Taiwan; and Faculty of Life Sciences, Institute of Biochemistry, Institute of Neuroscience, and Structural Biology Program, National Yang-Ming University, Taipei 112, Taiwan
| | - Ming-Shi Shiao
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei 114, Taiwan; Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei 112, Taiwan; and Faculty of Life Sciences, Institute of Biochemistry, Institute of Neuroscience, and Structural Biology Program, National Yang-Ming University, Taipei 112, Taiwan
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Mohr M, Klempt M, Rathkolb B, de Angelis MH, Wolf E, Aigner B. Hypercholesterolemia in ENU-induced mouse mutants. J Lipid Res 2004; 45:2132-7. [PMID: 15342683 DOI: 10.1194/jlr.m400236-jlr200] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Hypercholesterolemia is caused by multiple environmental factors and genetic predispositions, and plays an important role in the development and pathogenesis of various human diseases. In this study, we aimed to establish randomly mutant mouse lines showing hypercholesterolemia for their further use in the detection of novel causative alleles. In the Munich ENU Mouse Mutagenesis Project, clinical chemistry blood analysis was performed on more than 15,000 G1 mice and 230 G3 pedigrees of chemically mutagenized mice to detect dominant and recessive mutations leading to an increased plasma total cholesterol level. Using inbred C3HeB/FeJ mice we identified more than 100 animals consistently showing hypercholesterolemia. Transmission of the altered phenotype to the subsequent generations led to the production of nine hypercholesterolemic lines. A single line showed further obvious deviations in the analysis of additional clinical chemistry blood parameters. Thus, the lines produced will contribute to the search for alleles that selectively cause primary hypercholesterolemia.
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Affiliation(s)
- Manuela Mohr
- Institute of Molecular Animal Breeding and Biotechnology, Ludwig-Maximilians-University, Munich, Germany
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