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Zakaria Z, Zulkifle MF, Wan Hasan WAN, Azhari AK, Abdul Raub SH, Eswaran J, Soundararajan M, Syed Husain SNA. Epidermal growth factor receptor ( EGFR) gene alteration and protein overexpression in Malaysian triple-negative breast cancer (TNBC) cohort. Onco Targets Ther 2019; 12:7749-7756. [PMID: 31571924 PMCID: PMC6759283 DOI: 10.2147/ott.s214611] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 07/18/2019] [Indexed: 12/24/2022] Open
Abstract
Background Epidermal growth factor receptor (EGFR) is a member of the ErbB family of tyrosine kinase receptor proteins that plays important roles in tumour cell survival and proliferation. EGFR has been reported to be overexpressed in up to 78% of triple-negative breast cancer (TNBC) cases suggesting it as a potential therapeutic target. The clinical trials of anti-EGFR agents in breast cancer showed low response rates. However, a subgroup of patients demonstrated response to EGFR inhibitors highlighting the necessity to stratify patients, who might benefit from effective combination therapy that could include anti EGFR-agents. Population variability in EGFR expression warrants systematic evaluation in specific populations. Purpose To study EGFR alterations and expressions in a multi ethnic Malaysian TNBC patient cohort to determine the possibility of using anti-EGFR combinatorial therapy for this population. Patients and methods In this study, we evaluated 58 cases of Malaysian TNBC patient samples for EGFR gene copy number alteration and EGFR protein overexpression using fluorescence in-situ hybridization (FISH) and immunohistochemistry (IHC) methods, respectively. Results EGFR protein overexpression was observed in about 30% while 15.5% displayed high EGFR copy number including 5.17% gene amplification and over 10% high polysomy. There is a positive correlation between EGFR protein overexpression and gene copy number and over expression of EGFR is observed in ten out of the 48 low copy number cases (20.9%) without gene amplification. Conclusion This study provides the first glimpse of EGFR alterations and expressions in a multi ethnic Malaysian TNBC patient cohort emphasising the need for the nationwide large scale EGFR expression evaluation in Malaysia.
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Affiliation(s)
- Zubaidah Zakaria
- Cancer Research Centre (CaRC), Institute for Medical Research (IMR), National Institutes of Health (NIH), Ministry of Health (MOH), Setia Alam, Shah Alam 40170, Selangor Darul Ehsan, Malaysia
| | - Muhamad Farid Zulkifle
- Cancer Research Centre (CaRC), Institute for Medical Research (IMR), National Institutes of Health (NIH), Ministry of Health (MOH), Setia Alam, Shah Alam 40170, Selangor Darul Ehsan, Malaysia.,Department of Pathology, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre (UKMMC), Cheras, Kuala Lumpur 56000, Malaysia.,Nutrition, Metabolism and Cardiovascular Research Centre (NMCRC), Institute for Medical Research (IMR), National Institutes of Health (NIH), Ministry of Health (MOH), Setia Alam, 40170 Shah Alam, Selangor Darul Ehsan, Malaysia
| | - Wan Atiqah Najiah Wan Hasan
- Cancer Research Centre (CaRC), Institute for Medical Research (IMR), National Institutes of Health (NIH), Ministry of Health (MOH), Setia Alam, Shah Alam 40170, Selangor Darul Ehsan, Malaysia
| | - Azlah Kamilah Azhari
- Department of Pathology, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre (UKMMC), Cheras, Kuala Lumpur 56000, Malaysia.,Reference Specialised Laboratory, Pantai Premier Pathology Sdn. Bhd., Kuala Lumpur 59100, Malaysia
| | - Sayyidi Hamzi Abdul Raub
- Department of Pathology, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre (UKMMC), Cheras, Kuala Lumpur 56000, Malaysia.,Reference Specialised Laboratory, Pantai Premier Pathology Sdn. Bhd., Kuala Lumpur 59100, Malaysia
| | - Jeyanthy Eswaran
- Northern Institute for Cancer Research, Newcastle University, Newcastle-upon-Tyne, NE1 7RU, UK.,Newcastle University Medicine Malaysia, Gelang Patah, Johor 79200, Malaysia
| | - Meera Soundararajan
- Department of Applied Sciences, Faculty of Health and Life Sciences, Northumbria University, Newcastle-upon-Tyne NE1 8ST, UK
| | - Sharifah Noor Akmal Syed Husain
- Department of Pathology, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre (UKMMC), Cheras, Kuala Lumpur 56000, Malaysia.,Reference Specialised Laboratory, Pantai Premier Pathology Sdn. Bhd., Kuala Lumpur 59100, Malaysia
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2
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Mahas A, Potluri K, Kent MN, Naik S, Markey M. Copy number variation in archival melanoma biopsies versus benign melanocytic lesions. Cancer Biomark 2017; 16:575-97. [PMID: 27002761 DOI: 10.3233/cbm-160600] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Skin melanocytes can give rise to benign and malignant neoplasms. Discrimination of an early melanoma from an unusual/atypical benign nevus can represent a significant challenge. However, previous studies have shown that in contrast to benign nevi, melanoma demonstrates pervasive chromosomal aberrations. OBJECTIVE This substantial difference between melanoma and benign nevi can be exploited to discriminate between melanoma and benign nevi. METHODS Array-comparative genomic hybridization (aCGH) is an approach that can be used on DNA extracted from formalin-fixed paraffin-embedded (FFPE) tissues to assess the entire genome for the presence of changes in DNA copy number. In this study, high resolution, genome-wide single-nucleotide polymorphism (SNP) arrays were utilized to perform comprehensive and detailed analyses of recurrent copy number aberrations in 41 melanoma samples in comparison with 21 benign nevi. RESULTS We found statistically significant copy number gains and losses within melanoma samples. Some of the identified aberrations are previously implicated in melanoma. Moreover, novel regions of copy number alterations were identified, revealing new candidate genes potentially involved in melanoma pathogenesis. CONCLUSIONS Taken together, these findings can help improve melanoma diagnosis and introduce novel melanoma therapeutic targets.
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Affiliation(s)
- Ahmed Mahas
- Department of Biochemistry and Molecular Biology, Wright State University, Dayton, OH, USA
| | - Keerti Potluri
- Department of Biochemistry and Molecular Biology, Wright State University, Dayton, OH, USA
| | - Michael N Kent
- Department of Dermatology, Wright State University Boonshoft School of Medicine, Dayton, OH, USA.,Dermatopathology Laboratory of Central States, Dayton, OH, USA
| | - Sameep Naik
- Dermatopathology Laboratory of Central States, Dayton, OH, USA
| | - Michael Markey
- Department of Biochemistry and Molecular Biology, Wright State University, Dayton, OH, USA
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3
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Multicolor FISHs for simultaneous detection of genes and DNA segments on human chromosomes. Chromosome Res 2015; 23:649-62. [PMID: 25947045 DOI: 10.1007/s10577-015-9473-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Revised: 02/16/2015] [Accepted: 03/03/2015] [Indexed: 10/23/2022]
Abstract
We have developed a convenient multicolor fluorescent in situ hybridization (FISH) (five-, four-, three-, and two-color FISHs) for detecting specific genes/DNA segments on the human chromosomes. As a foundation of multicolor FISH, we first isolated 80 bacterial artificial chromosome (BAC) probes that specifically detect the peri-centromeres (peri-CEN) and subtelomeres (subTEL) of 24 different human chromosomes (nos. 1~22, X, and Y) by screening our homemade BAC library (Keio BAC library) consisting of 200,000 clones. Five-color FISH was performed using human DNA segments specific for peri-CEN or subTEL, which were labeled with five different fluorescent dyes [7-diethylaminocoumarin (DEAC): blue, fluorescein isothiocyanate (FITC): green, rhodamine 6G (R6G): yellow, TexRed: red, and cyanine5 (Cy5): purple]. To observe FISH signals under a fluorescence microscope, five optic filters were carefully chosen to avoid overlapping fluorescence emission. Five-color FISH and four-color FISH enabled us to accurately examine the numerical anomaly of human chromosomes. Three-color FISH using two specific BAC clones, that distinguish 5' half of oncogene epidermal growth factor receptor (EGFR) from its 3' half, revealed the amplification and truncation of EGFR in EGFR-overproducing cancer cells. Moreover, two-color FISH readily detected a fusion gene in leukemia cells such as breakpoint cluster region (BCR)/Abelson murine leukemia viral oncogene homologue (ABL) on the Philadelphia (Ph') chromosome with interchromosomal translocation. Some other successful cases such as trisomy 21 of Down syndrome are presented. Potential applications of multicolor FISH will be discussed.
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4
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Lauand C, Niero EL, Dias VM, Machado-Santelli GM. Cell cycle synchronization and BrdU incorporation as a tool to study the possible selective elimination of ErbB1 gene in the micronuclei in A549 cells. ACTA ACUST UNITED AC 2015; 48:382-91. [PMID: 25760027 PMCID: PMC4445660 DOI: 10.1590/1414-431x20144262] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Accepted: 12/10/2014] [Indexed: 11/22/2022]
Abstract
Lung cancer often exhibits molecular changes, such as the overexpression of the
ErbB1 gene that encodes epidermal growth factor receptor (EGFR).
ErbB1 amplification and mutation are associated with tumor
aggressiveness and low response to therapy. The aim of the present study was to
design a schedule to synchronize the cell cycle of A549 cell line (a non-small cell
lung cancer) and to analyze the possible association between the micronuclei (MNs)
and the extrusion of ErbB1 gene extra-copies. After double blocking,
by the process of fetal bovine serum deprivation and vincristine treatment, MNs
formation was monitored with 5-bromo-2-deoxyuridine (BrdU) incorporation, which is an
S-phase marker. Statistical analyses allowed us to infer that MNs may arise both in
mitosis as well as in interphase. The MNs were able to replicate their DNA and this
process seemed to be non-synchronous with the main cell nuclei. The presence of
ErbB1 gene in the MNs was evaluated by fluorescent in
situ hybridization (FISH). ErbB1 sequences were detected
in the MNs, but a relation between the MNs formation and extrusion of amplified
ErbB1could not be established. The present study sought to
elucidate the meaning of MNs formation and its association with the elimination of
oncogenes or other amplified sequences from the tumor cells.
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Affiliation(s)
- C Lauand
- Departamento de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
| | - E L Niero
- Departamento de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
| | - V M Dias
- Departamento de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
| | - G M Machado-Santelli
- Departamento de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
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Ceresa BP, Peterson JL. Cell and molecular biology of epidermal growth factor receptor. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2014; 313:145-78. [PMID: 25376492 DOI: 10.1016/b978-0-12-800177-6.00005-0] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The epidermal growth factor receptor (EGFR) has been one of the most intensely studied cell surface receptors due to its well-established roles in developmental biology, tissue homeostasis, and cancer biology. The EGFR has been critical for creating paradigms for numerous aspects of cell biology, such as ligand binding, signal transduction, and membrane trafficking. Despite this history of discovery, there is a continual stream of evidence that only the surface has been scratched. New ways of receptor regulation continue to be identified, each of which is a potential molecular target for manipulating EGFR signaling and the resultant changes in cell and tissue biology. This chapter is an update on EGFR-mediated signaling, and describes some recent developments in the regulation of receptor biology.
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Affiliation(s)
- Brian P Ceresa
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, USA
| | - Joanne L Peterson
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, USA
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6
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Lauand C, Rezende-Teixeira P, Cortez BA, Niero ELDO, Machado-Santelli GM. Independent of ErbB1 gene copy number, EGF stimulates migration but is not associated with cell proliferation in non-small cell lung cancer. Cancer Cell Int 2013; 13:38. [PMID: 23631593 PMCID: PMC3655000 DOI: 10.1186/1475-2867-13-38] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Accepted: 04/23/2013] [Indexed: 12/27/2022] Open
Abstract
Background Lung cancer often exhibits molecular changes, such as the overexpression of the ErbB1 gene. ErbB1 encodes epidermal growth factor receptor (EGFR), a tyrosine kinase receptor, involved mainly in cell proliferation and survival. EGFR overexpression has been associated with more aggressive disease, poor prognosis, low survival rate and low response to therapy. ErbB1 amplification and mutation are associated with tumor development and are implicated in ineffective treatment. The aim of the present study was to investigate whether the ErbB1 copy number affects EGFR expression, cell proliferation or cell migration by comparing two different cell lines. Methods The copies of ErbB1 gene was evaluated by FISH. Immunofluorescence and Western blotting were performed to determine location and expression of proteins mentioned in the present study. Proliferation was studied by flow cytometry and cell migration by wound healing assay and time lapse. Results We investigated the activation and function of EGFR in the A549 and HK2 lung cancer cell lines, which contain 3 and 6 copies of ErbB1, respectively. The expression of EGFR was lower in the HK2 cell line. EGFR was activated after stimulation with EGF in both cell lines, but this activation did not promote differences in cellular proliferation when compared to control cells. Inhibiting EGFR with AG1478 did not modify cellular proliferation, confirming previous data. However, we observed morphological alterations, changes in microfilament organization and increased cell migration upon EGF stimulation. However, these effects did not seem to be consequence of an epithelial-mesenchymal transition. Conclusion EGFR expression did not appear to be associated to the ErbB1 gene copy number, and neither of these aspects appeared to affect cell proliferation. However, EGFR activation by EGF resulted in cell migration stimulation in both cell lines.
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Affiliation(s)
- Camila Lauand
- Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of Sao Paulo, Av, Prof, Lineu Prestes, 1524, Butantã, São Paulo, SP 05508-000, Brazil.
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7
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Shao MM, Zhang F, Meng G, Wang XX, Xu H, Yu XW, Chen LY, Tse GM. Epidermal growth factor receptor gene amplification and protein overexpression in basal-like carcinoma of the breast. Histopathology 2011; 59:264-73. [DOI: 10.1111/j.1365-2559.2011.03921.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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8
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Zuo Q, Shi M, Chen J, Liao W. The Ras signaling pathway mediates cetuximab resistance in nasopharyngeal carcinoma. Biomed Pharmacother 2011; 65:168-74. [DOI: 10.1016/j.biopha.2011.02.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Accepted: 02/08/2011] [Indexed: 11/25/2022] Open
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9
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Matsuki E, Miyakawa Y, Asakawa S, Tsukada Y, Yamada T, Yokoyama K, Kudoh J, Ikeda Y, Okamoto S. Identification of Loss of p16 Expression and Upregulation of MDR-1 as Genetic Events Resulting from Two Novel Chromosomal Translocations Found in a Plasmablastic Lymphoma of the Uterus. Clin Cancer Res 2011; 17:2101-9. [DOI: 10.1158/1078-0432.ccr-10-2945] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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10
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Development of cetuximab-resistant human nasopharyngeal carcinoma cell lines and mechanisms of drug resistance. Biomed Pharmacother 2010; 64:550-8. [PMID: 20630698 DOI: 10.1016/j.biopha.2010.03.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2010] [Accepted: 03/26/2010] [Indexed: 11/21/2022] Open
Abstract
This work aimed to explore the induction of cetuximab-resistant human nasopharyngeal carcinoma (hNPC) 5-8F/Erbitux cells and the mechanisms of drug resistance. The 5-8F cells with high EGFR expression and cetuximab sensitivity were screened and then induced by stepwise exposure to increasing doses of cetuximab. Western blot was conducted to detect protein levels. Our results are as follows: we successfully induced the cetuximab-resistant 5-8F/Erbitux hNPC cells. After treatment with cetuximab for 3 and 5 days, the RI was 1.2 and 1.1, respectively. The 5-8F/Erbitux cells showed cross-resistance to 5-FU (P<0.01) and some resistance to Taxol (P>0.05) as well as enhanced sensitivity to DDP (P>0.05). The cells had increased levels of P-gP, IGF-1R, P-IGF-1R, K-ras, H-ras, and PTEN protein expression (P<0.001), while survivin decreased (P<0.001). Through sequence alignments, gene mutations in the PTEN gene at exons 5, 7, and 8, as well as the H-ras and K-ras genes in codons 12, 13, 59, and 61, were not observed. After transfection with H-ras-shRNA plasmid, the 5-8F/Erbitux cells showed reduced levels of gene and protein expression of H-ras and elevated sensitivity to cetuximab. In conclusion, gene amplification and overexpression of H-ras was the major mechanism that caused resistance of 5-8F/Erbitux cells to cetuximab, while the overexpression of the H-ras gene was probably associated with the over-activity of the IGF-1R signaling pathway. Gene deletion or mutation of PTEN was not associated with resistance of 5-8F/Erbitux cells to cetuximab.
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Buckley AF, Burgart LJ, Sahai V, Kakar S. Epidermal growth factor receptor expression and gene copy number in conventional hepatocellular carcinoma. Am J Clin Pathol 2008; 129:245-51. [PMID: 18208805 DOI: 10.1309/wf10qaaed3pp93bh] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Epidermal growth factor receptor (EGFR) is frequently overexpressed in hepatocellular carcinoma, but its relationship with EGFR gene copy number has not been studied. This study examined EGFR expression and gene copy number in hepatocellular carcinoma and evaluated their relationship to clinicopathologic features in 76 tumors. Moderate to strong expression of EGFR was observed by immunohistochemical analysis in 50 (66%) of 76 hepatocellular carcinomas. Fluorescence in situ hybridization (FISH) showed extra EGFR gene copies in 17 (45%) of 38 tumors. This was accompanied by gains of chromosome 7, indicating that this was the result of balanced polysomy rather than gene amplification. There was no correlation between EGFR expression by immunohistochemical analysis and gene copy number by FISH. EGFR expression showed borderline association with cirrhosis but not with other clinicopathologic parameters examined. EGFR overexpression is present in a majority of hepatocellular carcinomas, suggesting a role for EGFR antagonists in therapy. The increased expression does not correlate with an increase in the EGFR gene copy number.
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Affiliation(s)
- Anne F Buckley
- Departments of Pathology, UCSF and Veteran Affairs Medical Centers, San Francisco, CA 94121, USA
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Abd El All HS, Mishriky AM, Mohamed FA. Epidermal growth factor receptor in colorectal carcinoma: correlation with clinico-pathological prognostic factors. Colorectal Dis 2008; 10:170-8. [PMID: 17711501 DOI: 10.1111/j.1463-1318.2007.01306.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
OBJECTIVE This study was undertaken to determine the relationship between epidermal growth factor receptor (EGFR) status in primary colorectal cancer (CRC) to different clinico-pathological prognostic factors. METHOD Seventy-nine primary CRC were studied using four scoring systems: 1- EGFR pharmDx score, 2- score modified from the Hercept test [J Histo cytochem, 52 (2004) 893], 3- two additive scores with different cutoff points [Mod Pathol, 11 (1998) 155], 4- two multiplicative scores with different cutoff points [Ann Oncol, 16 (2005) 102]. RESULTS More than 10% membranous EGFR reactivity was identified in 46.8% (37/79) of the tumours. The intensity was classified as mild, moderate and strong representing 8.9%, 20.3% and 17.7% respectively. Strong correlation was found between the EGFR pharmDx and the proposed scores, at different cutoff points (P < 0.01). A strong correlation was found between EGFR expression, advanced clinical stage (P < 0.01), nodal involvement (P < 0.01) and lympho-vascular invasion (LV) (P < 0.05) in category I factors, poorly differentiated tumours in IIA (P < 0.05), infiltrative border configuration in IIB (P < 0.01), perineural invasion (PN) in III (P < 0.01), and larger tumours in IV (P < 0.01). Heterogenous staining was present in 46.3% of tumours and was associated with an increased score, LV and PN invasion and advanced clinical stage (P < 0.05). CONCLUSION Using a cut-off point of 10%, similar results with different scoring systems were obtained, representing standardization for EGFR interpretation. EGFR expression is correlated with conventional clinico-pathological prognostic factors.
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Affiliation(s)
- H S Abd El All
- Faculty of Medicine, Pathology, Suez Canal University, Ismailia, Egypt.
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Okabe T, Okamoto I, Tamura K, Terashima M, Yoshida T, Satoh T, Takada M, Fukuoka M, Nakagawa K. Differential constitutive activation of the epidermal growth factor receptor in non-small cell lung cancer cells bearing EGFR gene mutation and amplification. Cancer Res 2007; 67:2046-53. [PMID: 17332333 DOI: 10.1158/0008-5472.can-06-3339] [Citation(s) in RCA: 138] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The identification of somatic mutations in the tyrosine kinase domain of the epidermal growth factor receptor (EGFR) in patients with non-small cell lung cancer (NSCLC) and the association of such mutations with the clinical response to EGFR tyrosine kinase inhibitors (TKI), such as gefitinib and erlotinib, have had a substantial effect on the treatment of this disease. EGFR gene amplification has also been associated with an increased therapeutic response to EGFR-TKIs. The effects of these two types of EGFR alteration on EGFR function have remained unclear, however. We have now examined 16 NSCLC cell lines, including eight newly established lines from Japanese NSCLC patients, for the presence of EGFR mutations and amplification. Four of the six cell lines that harbor EGFR mutations were found to be positive for EGFR amplification, whereas none of the 10 cell lines negative for EGFR mutation manifested EGFR amplification, suggesting that these two types of EGFR alteration are closely associated. Endogenous EGFRs expressed in NSCLC cell lines positive for both EGFR mutation and amplification were found to be constitutively activated as a result of ligand-independent dimerization. Furthermore, the patterns of both EGFR amplification and EGFR autophosphorylation were shown to differ between cell lines harboring the two most common types of EGFR mutation (exon 19 deletion and L858R point mutation in exon 21). These results reveal distinct biochemical properties of endogenous mutant forms of EGFR expressed in NSCLC cell lines and may have implications for treatment of this condition.
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Affiliation(s)
- Takafumi Okabe
- Department of Medical Oncology, Kinki University School of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka 589-8511, Japan
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14
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Breuer RHJ, Postmus PE, Smit EF. Molecular pathology of non-small-cell lung cancer. Respiration 2005; 72:313-30. [PMID: 15942304 DOI: 10.1159/000085376] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2003] [Accepted: 07/29/2004] [Indexed: 01/22/2023] Open
Abstract
The molecular basis of lung carcinogenesis must be understood more fully and exploited to enhance survival rates of patients suffering from lung cancer. In this review we will discuss the major molecular alterations that occur in lung cancer. Emphasis is placed on alterations that occur early during carcinogenesis since they might be relevant for future screening programs. Finally we will shortly review new approaches that are used to study the molecular pathology of lung cancer and how they can be applied in a clinical setting.
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Affiliation(s)
- R H J Breuer
- Department of Pulmonology, Free University Medical Center, Amsterdam, The Netherlands
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Sauer T, Beraki K, Noren T, Garred O, Naess O. EGFR gene copy number heterogeneity in fine-needle aspiration cytology from breast carcinomas determined by chromogenic in situ hybridization. Diagn Cytopathol 2005; 33:228-32. [PMID: 16138375 DOI: 10.1002/dc.20338] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Most studies have shown epidermal growth factor receptor (EGFR) overexpression to be associated with poor prognostic factors in breast carcinomas. The relationship to EGFR gene copy number is unclear. The aim of our study was to investigate the heterogeneity of the EGFR gene copy number in breast carcinomas. The material consisted of air-dried smears from 29 breast carcinomas and 3 breast cancer cell lines (MCF-7, SKBR3, and T47D). Chromogenic in situ hybridization (CISH) was done using chromogenic detection. The mean signal numbers for EGFR gene and chromosome 7 as well as the EGFR gene/chromosome 7 centromere probe (CEP7) ratio were recorded. Immunohistochemical (IHC) staining was done on the corresponding paraffin sections. The copy number of the EGFR gene in each tumor/cell line ranged from 1.2 to 5.6. The EGFR gene/CEP7 ratio showed a biological continuum ranging from 0.59 to 1.94 with a mean of 1.04. EGFR gene copy loss was found in 16.6% of cases whereas copy gain was demonstrated in 19.4%. There was no relationship between IHC protein expression of EGFR and EGFR gene copy number or EGFR gene/CEP7 ratio.In conclusion, most breast carcinomas had a balanced EGFR gene/CEP7 copy number with a mean ratio of 1.04. Almost equal subpopulations revealed limited copy gain and copy loss. EGFR high dosage amplification, like in HER-2, was not demonstrated. Demonstration of EGFR gene copy loss might have a potential as a surrogate marker for EGFR gene mutation and/or deletion.
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Affiliation(s)
- Torill Sauer
- Department of Pathology, Ullevål University Hospital, Oslo, Norway.
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16
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Hirsch FR, Varella-Garcia M, Bunn PA, Di Maria MV, Veve R, Bremmes RM, Barón AE, Zeng C, Franklin WA. Epidermal growth factor receptor in non-small-cell lung carcinomas: correlation between gene copy number and protein expression and impact on prognosis. J Clin Oncol 2003; 21:3798-807. [PMID: 12953099 DOI: 10.1200/jco.2003.11.069] [Citation(s) in RCA: 1104] [Impact Index Per Article: 52.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
PURPOSE The epidermal growth factor receptor (EGFR) is frequently overexpressed in non-small-cell lung carcinoma (NSCLC), and EGFR inhibitors are promising new therapeutic agents. The molecular mechanisms responsible for EGFR overexpression are poorly understood. MATERIALS AND METHODS Gene copy number and protein status of EGFR were investigated in microarrayed tumors from 183 NSCLC patients, including squamous cell carcinoma (SCC; 89 patients) and non-SCC (94 patients) histologies. Protein expression was assessed by immunohistochemistry on a scale from 0 to 400 (percentage of positive cells x staining intensity). Gene and chromosome 7 copy numbers were identified by fluorescent in situ hybridization (FISH). RESULTS EGFR protein overexpression was observed in 62% of the NSCLC (25% scored 201 to 300; 37% scored 301 to 400), more frequently in SCC than non-SCC (82% v 44%; P <.001), and in 80% of the bronchioloalveolar carcinomas. The prevalent FISH patterns were balanced disomy (40%) and trisomy (38%) for EGFR gene and chromosome 7 (40%), whereas balanced polysomy was seen in 13% and gene amplification was seen in 9% of the patients. Gene copy number correlated with protein expression (r = 0.4; P <.001). EGFR overexpression or high gene copy numbers had no significant influence on prognosis. CONCLUSION EGFR overexpression is frequent in NSCLC, is most prominent in SCC, and correlates with increased gene copy number per cell. High gene copy numbers per cell showed a trend toward poor prognosis. It will be important to evaluate EGFR gene and EGFR protein status and signal protein expression to properly interpret future clinical trials using EGFR inhibitors.
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Affiliation(s)
- Fred R Hirsch
- Department of Pathology, University of Colorado Health Sciences Center, Denver, CO 80262, USA.
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Schulten HJ, Gunawan B, Otto F, Hassmann R, Hallermann C, Noebel A, Füzesi L. Cytogenetic characterization of complex karyotypes in seven established melanoma cell lines by multiplex fluorescence in situ hybridization and DAPI banding. CANCER GENETICS AND CYTOGENETICS 2002; 133:134-41. [PMID: 11943340 DOI: 10.1016/s0165-4608(01)00584-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We report the use of multiplex fluorescence in situ hybridization (M-FISH) to resolve chromosomal aberrations in seven established melanoma cell lines with hypotriploid to hypertetraploid complex karyotypes. By simultaneous identification of all human chromosomes in single FISH experiments using a set of 52 directly labeled, whole chromosome painting probes, cryptic chromosomal translocations and the origin of unclear chromosomal material in structural rearranged and marker chromosomes could be identified, refining the tumor karyotypes in all seven cell lines. The number of structural aberrations in each cell line assigned with combined M-FISH and DAPI banding analysis ranged from 15 to 45. Altogether, 275 breakpoints could be assigned to defined chromosomal regions or bands. The chromosome arms 1p, 6q, 7p, 9p, and 11q which are known to be nonrandomly associated with melanoma tumorigenesis, were frequently involved in chromosomal breaks and/or copy number changes. This study also demonstrated the practical usefulness of combining M-FISH with conventional cytogenetic banding techniques for the characterization of complex tumor karyotypes with massive genomic alterations.
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18
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Fosslien E. Biochemistry of cyclooxygenase (COX)-2 inhibitors and molecular pathology of COX-2 in neoplasia. Crit Rev Clin Lab Sci 2000; 37:431-502. [PMID: 11078056 DOI: 10.1080/10408360091174286] [Citation(s) in RCA: 187] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Several types of human tumors overexpress cyclooxygenase (COX) -2 but not COX-1, and gene knockout transfection experiments demonstrate a central role of COX-2 in experimental tumorigenesis. COX-2 produces prostaglandins that inhibit apoptosis and stimulate angiogenesis and invasiveness. Selective COX-2 inhibitors reduce prostaglandin synthesis, restore apoptosis, and inhibit cancer cell proliferation. In animal studies they limit carcinogen-induced tumorigenesis. In contrast, aspirin-like nonselective NSAIDs such as sulindac and indomethacin inhibit not only the enzymatic action of the highly inducible, proinflammatory COX-2 but the constitutively expressed, cytoprotective COX-1 as well. Consequently, nonselective NSAIDs can cause platelet dysfunction, gastrointestinal ulceration, and kidney damage. For that reason, selective inhibition of COX-2 to treat neoplastic proliferation is preferable to nonselective inhibition. Selective COX-2 inhibitors, such as meloxicam, celecoxib (SC-58635), and rofecoxib (MK-0966), are NSAIDs that have been modified chemically to preferentially inhibit COX-2 but not COX-1. For instance, meloxicam inhibits the growth of cultured colon cancer cells (HCA-7 and Moser-S) that express COX-2 but has no effect on HCT-116 tumor cells that do not express COX-2. NS-398 induces apoptosis in COX-2 expressing LNCaP prostate cancer cells and, surprisingly, in colon cancer S/KS cells that does not express COX-2. This effect may due to induction of apoptosis through uncoupling of oxidative phosphorylation and down-regulation of Bcl-2, as has been demonstrated for some nonselective NSAIDs, for instance, flurbiprofen. COX-2 mRNA and COX-2 protein is constitutively expressed in the kidney, brain, spinal cord, and ductus deferens, and in the uterus during implantation. In addition, COX-2 is constitutively and dominantly expressed in the pancreatic islet cells. These findings might somewhat limit the use of presently available selective COX-2 inhibitors in cancer prevention but will probably not deter their successful application for the treatment of human cancers.
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Affiliation(s)
- E Fosslien
- Department of Pathology, College of Medicine, University of Illinois at Chicago, 60612, USA.
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19
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Okada K, Sugihara H, Bamba M, Bamba T, Hattori T. Sequential numerical changes of chromosomes 7 and 18 in diffuse-type stomach cancer cell lines: combined comparative genomic hybridization, fluorescence in situ hybridization, and ploidy analyses. CANCER GENETICS AND CYTOGENETICS 2000; 118:99-107. [PMID: 10748289 DOI: 10.1016/s0165-4608(99)00182-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Sequential changes of chromosomal copy number were analyzed retrospectively in five diffuse-type gastric cancer cell lines by comparative genomic hybridization (CGH), DNA cytometry, and fluorescence in situ hybridization (FISH) with centromeric and painting probes. By CGH, we found loss of 18q21 in all of the cell lines and gains of 7p11-q31, 20q, and 22 in four of the five cell lines. Actual copy numbers of chromosomes 7 and 18 were determined by FISH: disomy 18 with (partial) loss of 18q in the two DNA-diploid cell lines (AGS and MKN-45), trisomy 7 in MKN-45, disomy 18 and tetrasomy 7 with one-copy loss of 7p and one-copy gain of 7q tip in DNA-triploid HSC-39/40A, and trisomy 18 and hexasomy 7 with one-copy loss of 7q in DNA-tetraploid KATO-III. Because the DNA aneuploidy is thought to result through tetraploidization, and the duplicated chromosomal changes in DNA aneuploid tumors seem to precede tetraploidization, the duplicated gain of chromosome 7 and one-copy loss of 7q in KATO-III were inferred to have occurred before and after tetraploidization, respectively. Similarly, HSC-39/40A were inferred to be preceded by the DNA-diploid stage with disomy 7 and monosomy 18. As the loss of 18q21 and the gain of 7p11-q31 were inferred to have occurred already in the DNA diploid stage in at least four and two of the cell lines, respectively, the 18q21 loss may be more important than the 7q gain as an earlier event in the genesis of diffuse-type stomach cancer. The combined CGH, FISH, and ploidy analyses thus give us a clue to extract important earlier events from the chromosomal changes that were screened by CGH alone.
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Affiliation(s)
- K Okada
- First Department of Pathology, Shiga University of Medical Science, Ohtsu, Shiga, Japan
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20
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Affiliation(s)
- L Chin
- Department of Dermatology, Harvard Medical School, Department of Adult Oncology, Dana-Farber Cancer Institute, 44 Binney Street, M413 Boston, Massachusetts, MA 02115, USA
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21
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Sauer T, Beraki K, Jebsen PW, Naess O. Numerical abnormalities of chromosome 7 in interphase cell nuclei of breast carcinoma have no impact on immunohistochemically determined EGFR status. APMIS 1999; 107:211-6. [PMID: 10225319 DOI: 10.1111/j.1699-0463.1999.tb01546.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIM OF STUDY To investigate the relationship between epidermal growth factor receptor (EGFR) status and numerical aberrations of chromosome 7 in breast carcinomas. DESIGN In situ hybridization (ISH) of interphase cell nuclei on air-dried fine-needle aspirates (FNAC) from 33 breast carcinomas was evaluated for numerical abnormalities in chromosome 6, 7, 12 and 17. Immunohistochemical staining of EGFR was performed on corresponding histological specimens. RESULTS 78% of the tumours were aneuploid by ISH. Aneusomy of chromosome 7 was found in 18 cases (60%). EGFR overexpression was observed in 30% of the carcinomas, and seven of nine were aneuploid by ISH. The same percentage of chromosome 7 aneusomy was found in both EGFR-positive and -negative cases. Five of seven EGFR-positive tumours revealed aneusomy of chromosome 7. CONCLUSION Numerical gain of chromosome 7 is a common finding, occurring in about 60% of breast carcinomas. Most EGFR-positive tumours are aneuploid and show numerical gain of chromosome 7, but abnormal numbers of chromosome 7 have no impact on the EGFR status.
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Affiliation(s)
- T Sauer
- Department of Pathology, Ullevaal University Hospital, Oslo, Norway
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22
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Nagasawa A, Kubota R, Imamura Y, Nagamine K, Wang Y, Asakawa S, Kudoh J, Minoshima S, Mashima Y, Oguchi Y, Shimizu N. Cloning of the cDNA for a new member of the immunoglobulin superfamily (ISLR) containing leucine-rich repeat (LRR). Genomics 1997; 44:273-9. [PMID: 9325048 DOI: 10.1006/geno.1997.4889] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We isolated cDNAs for a novel protein with a calculated molecular mass of 46 kDa, containing a leucine-rich repeat (LRR) with conserved flanking sequences and a C2-type immunoglobulin (Ig)-like domain. This novel protein was considered to be a new member of the Ig superfamily and was named ISLR (immunoglobulin superfamily containing LRR). These domains are known to be important for protein-protein interaction or cell adhesion, and therefore it is possible that the novel protein ISLR may also interact with other proteins or cells. Northern blot analysis showed the presence of a 2.4-kb transcript in various human tissues including retina, heart, skeletal muscle, prostate, ovary, small intestine, thyroid, adrenal cortex, testis, stomach, and spinal cord as well as fetal lung and fetal kidney. The ISLR gene was mapped on human chromosome 15q23-q24 by fluorescence in situ hybridization.
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Affiliation(s)
- A Nagasawa
- Department of Molecular Biology, Keio University School of Medicine, Tokyo, Japan
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23
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Kubota R, Noda S, Wang Y, Minoshima S, Asakawa S, Kudoh J, Mashima Y, Oguchi Y, Shimizu N. A novel myosin-like protein (myocilin) expressed in the connecting cilium of the photoreceptor: molecular cloning, tissue expression, and chromosomal mapping. Genomics 1997; 41:360-9. [PMID: 9169133 DOI: 10.1006/geno.1997.4682] [Citation(s) in RCA: 164] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We have isolated a human cDNA clone encoding a novel acidic protein of MW 55,000 that we designated "myocilin" since it has homology to myosin and is localized preferentially in the ciliary rootlet and basal body of the connecting cilium of photoreceptor cells. The deduced amino acid sequence of human myocilin showed significant homologies with nonmuscle myosin of Dictyostelium discoideum in the N-terminal region and also with olfactomedin of bullfrog in the C-terminal region. Myocilin contained a leucine zipper-like motif similar to that seen in kinectin and other cytoskeletal proteins. These findings suggest that myocilin is a novel cytoskeletal protein involved in the morphogenesis of ciliated neuroepithelium such as photoreceptor cells. The myocilin gene (MYOC) was mapped to human chromosome 1q23-q24 by fluorescence in situ hybridization.
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Affiliation(s)
- R Kubota
- Department of Molecular Biology, Keio University School of Medicine, Tokyo, Japan
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24
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Imamura Y, Kubota R, Wang Y, Asakawa S, Kudoh J, Mashima Y, Oguchi Y, Shimizu N. Human retina-specific amine oxidase (RAO): cDNA cloning, tissue expression, and chromosomal mapping. Genomics 1997; 40:277-83. [PMID: 9119395 DOI: 10.1006/geno.1996.4570] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
In search of candidate genes for hereditary retinal disease, we have employed a subtractive and differential cDNA cloning strategy and isolated a novel retina-specific cDNA. Nucleotide sequence analysis revealed an open reading frame of 2187 bp, which encodes a 729-amino-acid protein with a calculated molecular mass of 80,644 Da. The putative protein contained a conserved domain of copper amine oxidase, which is found in various species from bacteria to mammals. It showed the highest homology to bovine serum amine oxidase, which is believed to control the level of serum biogenic amines. Northern blot analysis of human adult and fetal tissues revealed that the protein is expressed abundantly and specifically in retina as a 2.7-kb transcript. Thus, we considered this protein a human retina-specific amine oxidase (RAO). The RAO gene (AOC2) was mapped by fluorescence in situ hybridization to human chromosome 17q21. We propose that AOC2 may be a candidate gene for hereditary ocular diseases.
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Affiliation(s)
- Y Imamura
- Department of Molecular Biology, Keio University School of Medicine, Tokyo, Japan
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25
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Muratake T, Hayashi S, Ichikawa T, Kumanishi T, Ichimura Y, Kuwano R, Minoshima S, Shimizu N, Takahashi Y. Structure, 5'-upstream sequence and chromosomal assignment of the human 14.3.3 eta chain gene in relation to the effects of methamphetamine. Ann N Y Acad Sci 1996; 801:64-75. [PMID: 8959024 DOI: 10.1111/j.1749-6632.1996.tb17432.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- T Muratake
- National Saigata Hospital, Niigata Prefecture, Japan
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26
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Wang Y, Minoshima S, Shimizu N. Cot-1 banding of human chromosomes using fluorescence in situ hybridization with Cy3 labeling. THE JAPANESE JOURNAL OF HUMAN GENETICS 1995; 40:243-52. [PMID: 8527798 DOI: 10.1007/bf01876182] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We developed a new chromosome banding method by in situ hybridization of human Cot-1 DNA as a probe. Clear banding was produced on metaphase chromosomes of lymphoblastoid cells after probe detection with a fluorescent dye Cy3. Comparison with the known banding patterns revealed a similarity to the R-banding with some significant differences: some centromeric heterochromatin regions show Cot-1 positive bands. This suggests that some repetitive sequences from the heterochromatin regions constitute a major component of Cot-1 DNA. This unique chromosome banding method, Cot-1 banding, may be used as a supplement to the conventional karyotype analysis. Scanning analysis of the fluorescence intensities of Cot-1 banding and Q-banding are useful for objectively analyzing the banding pattern including a detection of chromosome aberrations. The Cot-1 banding with Cy3 is particularly powerful when applied for the gene mapping by fluorescence in situ hybridization (FISH) because red fluorescence of Cy3 for chromosome staining can be readily distinguished from green fluorescence of fluorescein isothiocyanate (FITC) for probe labeling. Using this novel method, we mapped a 4 kb-DNA fragment from myelin protein zero (MPZ) gene on the chromosome 1q22 to q23.
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Affiliation(s)
- Y Wang
- Department of Molecular Biology, Keio University School of Medicine, Tokyo, Japan
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27
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Sakai K, Ohta T, Minoshima S, Kudoh J, Wang Y, de Jong PJ, Shimizu N. Human ribosomal RNA gene cluster: identification of the proximal end containing a novel tandem repeat sequence. Genomics 1995; 26:521-6. [PMID: 7607675 DOI: 10.1016/0888-7543(95)80170-q] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Human ribosomal RNA genes (rDNA) are arranged as tandem repeat clusters on the short arms of five pairs of acrocentric chromosomes. We have demonstrated that a majority of the rDNA clusters are detected as 3-Mb DNA fragments when released from human genomic DNA by EcoRV digestion. This indicated the absence of the EcoRV restriction site within the rDNA clusters. We then screened for rDNA-positive cosmid clones using a chromosome 22-specific cosmid library that was constructed from MboI partial digests of the flow-sorted chromosomes. Three hundred twenty rDNA-positive clones negative for the previously reported distal flanking sequence (pACR1) were chosen and subjected to EcoRV digestion. Seven clones susceptible to EcoRV were further characterized as candidate clones that might have been derived from the junctions of the 3-Mb rDNA cluster. We identified one clone containing part of the rDNA unit sequence and a novel flanking sequence. Detailed analysis of this unique clone revealed that the coding region of the last rRNA gene located at the proximal end of the cluster is interrupted with a novel sequence of approximately 147 bp that is tandemly repeated and is connected with an intervening 68-bp unique sequence. This junction sequence was readily amplified from chromosomes 21 and 15 as well as 22 using the polymerase chain reaction. Fluorescence in situ hybridization further indicated that the approximately 147-bp sequence repeat is commonly distributed among all the acrocentric short arms.
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Affiliation(s)
- K Sakai
- Department of Molecular Biology, Keio University School of Medicine, Tokyo, Japan
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28
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Kubota R, Wang Y, Minoshima S, Kudoh J, Mashima Y, Oguchi Y, Shimizu N. Mapping of the human gene for a melanocyte protein Pmel 17 (D12S53E) to chromosome 12q13-q14. Genomics 1995; 26:430-1. [PMID: 7601481 DOI: 10.1016/0888-7543(95)80239-i] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- R Kubota
- Department of Molecular Biology, Keio University School of Medicine, Tokyo, Japan
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29
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Shimizu N, Wang Y, Minoshima S, Ishitoya J. Detection of epidermal growth factor receptor gene amplification in human squamous cell carcinomas using fluorescence in situ hybridization. Jpn J Cancer Res 1994; 85:567-71. [PMID: 8063608 PMCID: PMC5919517 DOI: 10.1111/j.1349-7006.1994.tb02397.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The gene for epidermal growth factor receptor (EGFR) is associated with development of certain human cancers. In this study, we employed the improved fluorescence in situ hybridization technique to detect EGFR gene amplification in cell lines and tissue sections from human squamous cell carcinomas. We detected multiple distinct signals as arrayed amplicons on metaphase chromosomes and interphase nuclei of tumor cells. Our results provide a basis for rapid and quantitative DNA diagnosis of the EGFR gene amplification in individual cells of tumor specimens.
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Affiliation(s)
- N Shimizu
- Department of Molecular Biology, Keio University School of Medicine, Tokyo
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