1
|
Tsuchida N, Murugan AK, Grieco M. Kirsten Ras* oncogene: significance of its discovery in human cancer research. Oncotarget 2018; 7:46717-46733. [PMID: 27102293 PMCID: PMC5216832 DOI: 10.18632/oncotarget.8773] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 04/10/2016] [Indexed: 12/24/2022] Open
Abstract
The KRAS/ K-RAS oncogene is crucially involved in human cancer. The term "oncogene" -- i.e., a gene able to transform a normal cell into a tumor cell - was introduced in 1969, but the word was not used in the human carcinogenesis literature until much later. Transforming Kras and Hras oncogenes from the Kirsten and Harvey sarcoma viruses were not identified until the early 1980s due to the complicated structures of the viral genomes. Orthologs of these viral oncogenes were then found in transforming DNA fragments in human cancers in the form of mutated versions of the HRAS and KRAS proto-oncogenes. Thus, RAS genes were the first human oncogenes to be identified. Subsequent studies showed that mutated KRAS acted as an in vivo oncogenic driver, as indicated by studies of anti-EGFR therapy for metastatic colorectal cancers. This review addresses the historical background and experimental studies that led to the discovery of Kirsten Ras as an oncogene, the role of mutated KRAS in human carcinogenesis, and recent therapeutic studies of cancer cells with KRAS mutations.
Collapse
Affiliation(s)
- Nobuo Tsuchida
- Graduate School of Medical and Dental Sciences, Tokyo Medical Dental University, Yushima, Bunkyo-ku, Tokyo, Japan
| | | | - Michele Grieco
- DiSTABiF, Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Seconda Università di Napoli, Caserta, Italy
| |
Collapse
|
2
|
Ghanam AR, Xu Q, Ke S, Azhar M, Cheng Q, Song X. Shining the Light on Senescence Associated LncRNAs. Aging Dis 2017; 8:149-161. [PMID: 28400982 PMCID: PMC5362175 DOI: 10.14336/ad.2016.0810] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 08/10/2016] [Indexed: 12/12/2022] Open
Abstract
Cellular senescence can be described as a complex stress response that leads to irreversible cell cycle arrest. This process was originally described as an event that primary cells go through after many passages of cells during cell culture. More recently, cellular senescence is viewed as a programmed process by which the cell displays a senescence phenotype when exposed to a variety of stresses. Cellular senescence has been implicated in tumor suppression and aging such that senescence may contribute to both tumor progression and normal tissue repair. Here, we review different forms of cellular senescence, as well as current biomarkers used to identify senescent cells in vitro and in vivo. Additionally, we highlight the role of senescence-associated long noncoding RNAs (lncRNAs).
Collapse
Affiliation(s)
- A R Ghanam
- 1CAS Key Laboratory of Brain Function and Disease, CAS Center for Excellence in Molecular Cell Science, Collaborative Innovation Center of Chemistry for Life Sciences, School of Life Sciences, University of Science and Technology of China, Hefei 230027, China.; 2Collage of Veterinary Medicine, Suez Canal University, Ismailia 41522, Egypt
| | - Qianlan Xu
- 1CAS Key Laboratory of Brain Function and Disease, CAS Center for Excellence in Molecular Cell Science, Collaborative Innovation Center of Chemistry for Life Sciences, School of Life Sciences, University of Science and Technology of China, Hefei 230027, China
| | - Shengwei Ke
- 1CAS Key Laboratory of Brain Function and Disease, CAS Center for Excellence in Molecular Cell Science, Collaborative Innovation Center of Chemistry for Life Sciences, School of Life Sciences, University of Science and Technology of China, Hefei 230027, China
| | - Muhammad Azhar
- 1CAS Key Laboratory of Brain Function and Disease, CAS Center for Excellence in Molecular Cell Science, Collaborative Innovation Center of Chemistry for Life Sciences, School of Life Sciences, University of Science and Technology of China, Hefei 230027, China
| | - Qingyu Cheng
- 1CAS Key Laboratory of Brain Function and Disease, CAS Center for Excellence in Molecular Cell Science, Collaborative Innovation Center of Chemistry for Life Sciences, School of Life Sciences, University of Science and Technology of China, Hefei 230027, China
| | - Xiaoyuan Song
- 1CAS Key Laboratory of Brain Function and Disease, CAS Center for Excellence in Molecular Cell Science, Collaborative Innovation Center of Chemistry for Life Sciences, School of Life Sciences, University of Science and Technology of China, Hefei 230027, China
| |
Collapse
|
3
|
Athuluri-Divakar SK, Vasquez-Del Carpio R, Dutta K, Baker SJ, Cosenza SC, Basu I, Gupta YK, Reddy MVR, Ueno L, Hart JR, Vogt PK, Mulholland D, Guha C, Aggarwal AK, Reddy EP. A Small Molecule RAS-Mimetic Disrupts RAS Association with Effector Proteins to Block Signaling. Cell 2016; 165:643-55. [PMID: 27104980 PMCID: PMC5006944 DOI: 10.1016/j.cell.2016.03.045] [Citation(s) in RCA: 206] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 12/09/2015] [Accepted: 03/28/2016] [Indexed: 02/07/2023]
Abstract
Oncogenic activation of RAS genes via point mutations occurs in 20%-30% of human cancers. The development of effective RAS inhibitors has been challenging, necessitating new approaches to inhibit this oncogenic protein. Functional studies have shown that the switch region of RAS interacts with a large number of effector proteins containing a common RAS-binding domain (RBD). Because RBD-mediated interactions are essential for RAS signaling, blocking RBD association with small molecules constitutes an attractive therapeutic approach. Here, we present evidence that rigosertib, a styryl-benzyl sulfone, acts as a RAS-mimetic and interacts with the RBDs of RAF kinases, resulting in their inability to bind to RAS, disruption of RAF activation, and inhibition of the RAS-RAF-MEK pathway. We also find that ribosertib binds to the RBDs of Ral-GDS and PI3Ks. These results suggest that targeting of RBDs across multiple signaling pathways by rigosertib may represent an effective strategy for inactivation of RAS signaling.
Collapse
Affiliation(s)
- Sai Krishna Athuluri-Divakar
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029, USA; Department of Structural and Chemical Biology, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029, USA
| | - Rodrigo Vasquez-Del Carpio
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029, USA; Department of Structural and Chemical Biology, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029, USA
| | - Kaushik Dutta
- New York Structural Biology Center, 89 Convent Avenue, New York, NY 10027, USA
| | - Stacey J Baker
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029, USA; Department of Structural and Chemical Biology, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029, USA
| | - Stephen C Cosenza
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029, USA; Department of Structural and Chemical Biology, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029, USA
| | - Indranil Basu
- Department of Radiation Oncology, Albert Einstein College of Medicine of Yeshiva University, 1300 Morris Park Avenue, Bronx, NY 10461, USA
| | - Yogesh K Gupta
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029, USA; Department of Structural and Chemical Biology, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029, USA
| | - M V Ramana Reddy
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029, USA; Department of Structural and Chemical Biology, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029, USA
| | - Lynn Ueno
- The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Jonathan R Hart
- The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Peter K Vogt
- The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - David Mulholland
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029, USA; Department of Structural and Chemical Biology, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029, USA
| | - Chandan Guha
- Department of Radiation Oncology, Albert Einstein College of Medicine of Yeshiva University, 1300 Morris Park Avenue, Bronx, NY 10461, USA
| | - Aneel K Aggarwal
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029, USA; Department of Structural and Chemical Biology, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029, USA
| | - E Premkumar Reddy
- Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029, USA; Department of Structural and Chemical Biology, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, NY 10029, USA.
| |
Collapse
|
4
|
Abstract
The search for specificity in cancers has been a holy grail in cancer immunology. Cancer geneticists have long known that cancers harbor transforming and other mutations. Immunologists have long known that inbred mice can be immunized against syngeneic cancers, indicating the existence of cancer-specific antigens. With the technological advances in high-throughput DNA sequencing and bioinformatics, the genetic and immunologic lines of inquiry are now converging to provide definitive evidence that human cancers are vastly different from normal tissues at the genetic level, and that some of these differences are recognized by the immune system. The very vastness of genetic changes in cancers now raises different question. Which of the many cancer-specific genetic (genomic) changes are actually recognized by the immune system, and why? New observations are now beginning to probe these vital issues with unprecedented resolution and are informing a new generation of studies in human cancer immunotherapy.
Collapse
Affiliation(s)
- Pramod K Srivastava
- Carole and Ray Neag Comprehensive Cancer Center and the Department of Immunology, University of Connecticut School of Medicine, Farmington, Connecticut.
| |
Collapse
|
5
|
Lim YH, Ovejero D, Sugarman JS, Deklotz CMC, Maruri A, Eichenfield LF, Kelley PK, Jüppner H, Gottschalk M, Tifft CJ, Gafni RI, Boyce AM, Cowen EW, Bhattacharyya N, Guthrie LC, Gahl WA, Golas G, Loring EC, Overton JD, Mane SM, Lifton RP, Levy ML, Collins MT, Choate KA. Multilineage somatic activating mutations in HRAS and NRAS cause mosaic cutaneous and skeletal lesions, elevated FGF23 and hypophosphatemia. Hum Mol Genet 2013; 23:397-407. [PMID: 24006476 DOI: 10.1093/hmg/ddt429] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Pathologically elevated serum levels of fibroblast growth factor-23 (FGF23), a bone-derived hormone that regulates phosphorus homeostasis, result in renal phosphate wasting and lead to rickets or osteomalacia. Rarely, elevated serum FGF23 levels are found in association with mosaic cutaneous disorders that affect large proportions of the skin and appear in patterns corresponding to the migration of ectodermal progenitors. The cause and source of elevated serum FGF23 is unknown. In those conditions, such as epidermal and large congenital melanocytic nevi, skin lesions are variably associated with other abnormalities in the eye, brain and vasculature. The wide distribution of involved tissues and the appearance of multiple segmental skin and bone lesions suggest that these conditions result from early embryonic somatic mutations. We report five such cases with elevated serum FGF23 and bone lesions, four with large epidermal nevi and one with a giant congenital melanocytic nevus. Exome sequencing of blood and affected skin tissue identified somatic activating mutations of HRAS or NRAS in each case without recurrent secondary mutation, and we further found that the same mutation is present in dysplastic bone. Our finding of somatic activating RAS mutation in bone, the endogenous source of FGF23, provides the first evidence that elevated serum FGF23 levels, hypophosphatemia and osteomalacia are associated with pathologic Ras activation and may provide insight in the heretofore limited understanding of the regulation of FGF23.
Collapse
|
6
|
Nandan MO, Yang VW. An Update on the Biology of RAS/RAF Mutations in Colorectal Cancer. CURRENT COLORECTAL CANCER REPORTS 2011; 7:113-120. [PMID: 21625338 DOI: 10.1007/s11888-011-0086-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Deaths caused by colorectal cancer (CRC) are among the leading causes of cancer-related death in the United States and around the world. Approximately 150,000 Americans are diagnosed with CRC each year and around 50,000 will die from it. Mutations in many key genes have been identified that are important to the pathogenesis of CRC. Among the genes mutated in CRC, RAS and RAF mutations are common events. Both RAS and RAF are critical mediators of the mitogen-activated protein kinase (MAPK) pathway that is involved in regulating cellular homeostasis, including proliferation, survival, and differentiation. In this review, we provide a historical perspective and update on RAS/RAF mutations as related to colorectal cancer. Additionally, we will review recent mouse models of RAS and RAF mutations that have an impact on CRC research.
Collapse
Affiliation(s)
- Mandayam O Nandan
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | | |
Collapse
|
7
|
Zeidler W, Egle C, Ribeiro S, Wagner A, Katunin V, Kreutzer R, Rodnina M, Wintermeyer W, Sprinzl M. Site-Directed Mutagenesis of Thermus thermophilus Elongation Factor Tu. ACTA ACUST UNITED AC 2008. [DOI: 10.1111/j.1432-1033.1995.0596j.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
8
|
Kilbey A, Terry A, Cameron ER, Neil JC. Oncogene-induced senescence: an essential role for Runx. Cell Cycle 2008; 7:2333-40. [PMID: 18677118 DOI: 10.4161/cc.6368] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Affiliation(s)
- Anna Kilbey
- Molecular Oncology Laboratory, Institute of Comparative Medicine, Faculty of Veterinary Medicine, University of Glasgow, Glasgow, United Kingdom.
| | | | | | | |
Collapse
|
9
|
Mildvan AS, Fry DC. NMR studies of the mechanism of enzyme action. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2006; 59:241-313. [PMID: 3544711 DOI: 10.1002/9780470123058.ch6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|
10
|
Fryer BH, Field J. Rho, Rac, Pak and angiogenesis: old roles and newly identified responsibilities in endothelial cells. Cancer Lett 2005; 229:13-23. [PMID: 16157214 DOI: 10.1016/j.canlet.2004.12.009] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2004] [Accepted: 12/03/2004] [Indexed: 01/09/2023]
Abstract
Angiogenesis-the develoment of microvasculature-requires, in part, directed endothelial cell motility and responsiveness to external signals. Several of the proteins, which modulate and/or direct endothelial cell motility and morphology in angiogenesis are the Rho GTPases (Rho, Rac, and Cdc42) and Pak (a downstream effector of Rac and Cdc42). Previously, overexpression and activation of Rho GTPases and Pak had been implicated in the development of cancer, through their roles in cancer cell transformation, stimulation of proliferation, inhibition of apoptosis, and migration. Yet regardless of the transformed status of cells within a tumor, without a blood supply most tumors cannot grow larger than 1-2 mm. The blood supply in tumors is provided by capillaries formed of endothelial cells in a process called angiogenesis. Consequently, there is enormous interest in the role of the wild type endothelial cells-and the signaling mechanisms required to support angiogenesis and subsequent growth of metastatic and aggressive cancers. Recent work has begun to uncover the roles of the Rho GTPases and Pak in the regulation of normal endothelial cell function. This review will discuss the current literature regarding the roles of Rho and Rac, and the Rac effector-Pak, in endothelial cells, and we will propose new avenues of research for interaction of the AGC kinase-PKG, with the Rho GTPases and Pak in the cell motility and cell morphology of endothelial cells.
Collapse
Affiliation(s)
- Benjamin H Fryer
- Department of Pharmacology, School of Medicine, University of Pennsylvania, 3620 Hamilton Walk, Philadelphia, PA 19104-6084, USA
| | | |
Collapse
|
11
|
Abstract
Slow transforming retroviruses, such as the Moloney murine leukemia virus (M-MuLV), induce tumors upon infection of a host after a relatively long latency period. The underlying mechanism leading to cell transformation is the activation of proto-oncogenes or inactivation of tumor suppressor genes as a consequence of proviral insertions into the host genome. Cells carrying proviral insertions that confer a selective advantage will preferentially grow out. This means that proviral insertions mark genes contributing to tumorigenesis, as was demonstrated by the identification of numerous proto-oncogenes in retrovirally induced tumors in the past. Since cancer is a complex multistep process, the proviral insertions in one clone of tumor cells also represent oncogenic events that cooperate in tumorigenesis. Novel advances, such as the launch of the complete mouse genome, high-throughput isolation of proviral flanking sequences, and genetically modified animals have revolutionized proviral tagging into an elegant and efficient approach to identify signaling pathways that collaborate in cancer.
Collapse
Affiliation(s)
- Harald Mikkers
- Division of Molecular Genetics and Centre of Biomedical Genetics, Netherlands Cancer Institute 1066 CX, Amsterdam, The Netherlands
| | | |
Collapse
|
12
|
Fukami T, Fukuhara H, Kuramochi M, Maruyama T, Isogai K, Sakamoto M, Takamoto S, Murakami Y. Promoter methylation of the TSLC1 gene in advanced lung tumors and various cancer cell lines. Int J Cancer 2003; 107:53-9. [PMID: 12925956 DOI: 10.1002/ijc.11348] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We previously identified TSLC1, a tumor suppressor gene in human nonsmall cell lung cancer (NSCLC). TSLC1 belongs to immunoglobulin superfamily molecules and is involved in cell adhesion. Loss of TSLC1 expression was strongly correlated with the promoter hypermethylation in several NSCLC cell lines. Here, we examined the methylation status of the TSLC1 gene promoter in 48 primary NSCLC tumors by bisulfite SSCP in combination with bisulfite sequencing. Six CpG sites around the promoter regions were significantly methylated in 21 of 48 primary NSCLC tumors (44%). Promoter methylation was more likely to be observed in relatively advanced tumors with TNM classification of pT2, pT3 or pT4 (19 of 33, 58%) than in those with pT1 (2 of 15, 13%), suggesting that alteration of TSLC1 would be involved in the progression of human NSCLC. Loss of TSLC1 expression was also observed in 20 of 46 (43%) human cancer cell lines, including those from esophageal (3 of 3), gastric (8 of 9), ovarian (2 of 5), endometrial (2 of 2), breast (1 of 3), colorectal (2 of 8) and small cell lung cancers (2 of 10). Combined analysis of promoter methylation and the allelic state in these cell lines indicated that the TSLC1 gene was often silenced not only by mono-allelic methylation associated with loss of the other allele but also through bi-allelic methylation. These results suggest that alteration of TSLC1 would be involved in advanced NSCLC as well as in many other human cancers.
Collapse
Affiliation(s)
- Takeshi Fukami
- Tumor Suppression & Functional Genomics Project, University of Tokyo, School of Medicine, Tokyo, Japan
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Ferbeyre G, de Stanchina E, Lin AW, Querido E, McCurrach ME, Hannon GJ, Lowe SW. Oncogenic ras and p53 cooperate to induce cellular senescence. Mol Cell Biol 2002; 22:3497-508. [PMID: 11971980 PMCID: PMC133786 DOI: 10.1128/mcb.22.10.3497-3508.2002] [Citation(s) in RCA: 218] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Oncogenic activation of the mitogen-activated protein (MAP) kinase cascade in murine fibroblasts initiates a senescence-like cell cycle arrest that depends on the ARF/p53 tumor suppressor pathway. To investigate whether p53 is sufficient to induce senescence, we introduced a conditional murine p53 allele (p53(val135)) into p53-null mouse embryonic fibroblasts and examined cell proliferation and senescence in cells expressing p53, oncogenic Ras, or both gene products. Conditional p53 activation efficiently induced a reversible cell cycle arrest but was unable to induce features of senescence. In contrast, coexpression of oncogenic ras or activated mek1 with p53 enhanced both p53 levels and activity relative to that observed for p53 alone and produced an irreversible cell cycle arrest that displayed features of cellular senescence. p19(ARF) was required for this effect, since p53(-/-) ARF(-/-) double-null cells were unable to undergo senescence following coexpression of oncogenic Ras and p53. Although the levels of exogenous p53 achieved in ARF-null cells were relatively low, the stabilizing effects of p19(ARF) on p53 could not explain the cooperation between oncogenic Ras and p53 in promoting senescence. Hence, enforced p53 expression without oncogenic ras in p53(-/-) mdm2(-/-) double-null cells produced extremely high p53 levels but did not induce senescence. Taken together, our results indicate that oncogenic activation of the MAP kinase pathway in murine fibroblasts converts p53 into a senescence inducer through both quantitative and qualitative mechanisms.
Collapse
Affiliation(s)
- Gerardo Ferbeyre
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA
| | | | | | | | | | | | | |
Collapse
|
14
|
Beránek M, Bures J, Palicka V, Jandík P, Langr F, Nejedlá E. A relationship between K-ras gene mutations and some clinical and histologic variables in patients with primary colorectal carcinoma. Clin Chem Lab Med 1999; 37:723-7. [PMID: 10510729 DOI: 10.1515/cclm.1999.111] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Mutations in the Kirsten ras 2 (K-ras) gene were described as early events in the process of colorectal carcinogenesis. The aim of this study was to find a possible relationship between the presence of K-ras mutation in samples of primary colorectal carcinomas and the clinico-pathological data of the investigated patients. Mutation in codon 12 of the K-ras gene was determined in 18 of 53 colorectal carcinomas (34%) in our group of patients. The presence of K-ras gene mutations was not related to gender, age of subject at diagnosis, staging or cancer location (p > 0.05). Sixteen of the 42 (38%) moderately differentiated carcinomas, and two of the eight (25%) well differentiated carcinomas contained K-ras mutation in codon 12, but none of the three poorly differentiated carcinomas contained the mutation. Moderately differentiated tumours contained an aspartate code GAT (in eight cases), a valine code GTT (in six cases), an alanine code GCT (in one case) and a serine code AGT (in one case) in codon 12. Well differentiated tumours contained only the valine code GTT (two cases). Our results show that the frequency of mutations in the K-ras gene in carcinomas in Central Europe is not different from the frequencies found in other parts of the world. The homogeneous incidence of K-ras mutation does not seem to be related to ethnic factors, dietary habits, or the composition of the diet.
Collapse
Affiliation(s)
- M Beránek
- Institute of Clinical Biochemistry and Diagnostics, University Hospital, Hradec Králové, Czech Republic
| | | | | | | | | | | |
Collapse
|
15
|
Andreú T, Beckers T, Thoenes E, Hilgard P, von Melchner H. Gene trapping identifies inhibitors of oncogenic transformation. The tissue inhibitor of metalloproteinases-3 (TIMP3) and collagen type I alpha2 (COL1A2) are epidermal growth factor-regulated growth repressors. J Biol Chem 1998; 273:13848-54. [PMID: 9593730 DOI: 10.1074/jbc.273.22.13848] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A gene trap strategy has been used to identify genes that are repressed in cells transformed by an activated epidermal growth factor (EGF)/EGF receptor signal transduction pathway. EGF receptor-expressing NIH3T3 cells (HER1 cells) were infected with a retrovirus containing coding sequences for the human CD2 antigen and for secreted alkaline phosphatase in the U3 region. By selecting for and against CD2 expression, we obtained clones in which the gene trap had integrated into genes selectively repressed by EGF. Two of these clones encoded for the secreted extracellular matrix proteins TIMP3 and COL1A2. We show here that both genes are downstream targets of RAS and are specifically repressed by EGF-induced transformation. Moreover, this strategy tags tumor suppressor genes in their normal chromosomal location, thereby improving target-specific screens for antineoplastic drugs.
Collapse
Affiliation(s)
- T Andreú
- Laboratory for Molecular Hematology, Department of Hematology, University of Frankfurt Medical School, Weismüllerstrasse 45, Frankfurt am Main, Germany
| | | | | | | | | |
Collapse
|
16
|
Abstract
In order to investigate whether two common types of colorectal cancer with different gross appearances share the same incidence of K-ras mutation, the occurrence of a point mutation in codon 12 or codon 13 of the K-ras oncogene was determined in 50 cases of colorectal carcinoma. The PCR technique was employed, followed by RFLP analysis and sequencing to identify specific point mutations. No correlation was found between the presence of a K-ras gene mutation and histological parameters. A strong association was found between K-ras mutations and the gross polypoid appearance of colorectal carcinoma (polypoid 73% versus ulcerative 8%). The results indicate a preferential association with the K-ras oncogene involved in polypoid type colorectal carcinoma.
Collapse
Affiliation(s)
- J M Chiang
- Division of Colon and Rectal Surgery, Chang Gung Memorial Hospital, Taipei, Taiwan
| |
Collapse
|
17
|
Corbley MJ. Transformation by ras suppresses expression of the neurotrophic growth factor pleiotrophin. J Biol Chem 1997; 272:24696-702. [PMID: 9305941 DOI: 10.1074/jbc.272.39.24696] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
An 18-kDa protein (p18) was detected in lysates and conditioned medium from contact-arrested NIH 3T3 fibroblasts, but was not detected when the cells were transformed by the oncogene ras. Analysis of transformation-defective cell clones generated after mutagenesis of the ras-retroviral vector used to transduce the ras gene showed an inverse correlation between p18 expression and the degree of transformation. p18 expression was high in non-transformed clones, intermediate in a partially transformed clone, undetectable in fully transformed clones, and detectable only at the non-permissive temperature in a clone which was cold-sensitive for ras transformation. In non-transformed cells, p18 expression varied with the degree of confluence. It was almost undetectable in medium from sparse, proliferating cells, but increased as the cells approached confluence and peaked 2-4 days after confluence. Microsequencing of partially purified p18 identified it as the developmentally regulated neurotrophic factor pleiotrophin. In further experiments, pleiotrophin was undetectable or almost undetectable in medium from fully transformed cells expressing the oncogenes v-src, truncated c-raf, activated c-fms, or polyomavirus middle tumor antigen; it was low but easily detectable in medium from SV40 large tumor antigen-expressing cells, which form soft agar colonies but not foci. Thus, pleiotrophin expression in NIH 3T3 cells is associated with quiescence, and suppression of pleiotrophin is related to oncogenic transformation.
Collapse
Affiliation(s)
- M J Corbley
- Division of Cellular and Molecular Biology, Dana-Farber Cancer Institute, Boston, Massachusetts 02115, USA.
| |
Collapse
|
18
|
Affiliation(s)
- D M Leonard
- Parke-Davis Pharmaceutical Research, Division of Warner-Lambert Company, Ann Arbor, Michigan 48105, USA
| |
Collapse
|
19
|
Guinn BA, Mills KI. p53 mutations, methylation and genomic instability in the progression of chronic myeloid leukaemia. Leuk Lymphoma 1997; 26:211-26. [PMID: 9322884 DOI: 10.3109/10428199709051771] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In chronic myeloid leukaemia (CML), as with other tumour types, mutations of the p53 gene are associated with disease progression. Changes in regional methylation of DNA with CML tumour development have also been demonstrated. Methylation is one mechanism by which gene expression is controlled and the CpG sites, which are the targets of DNA methylation, are also the sites of a number of the mutations found in the p53 gene. Cells harbouring mutant p53 have been shown to accumulate further genomic and genetic aberrations and methylation which alters the conformation of DNA is also believed to play a role in genomic stability. There appears to be an interplay between p53 deregulation and changing methylation patterns with the progression of CML. The cause and effect of changes in both of these critical gene regulating, DNA repair and genomic stability factors and their deviation during the progression of CML will be discussed.
Collapse
MESH Headings
- Animals
- DNA Methylation
- DNA, Neoplasm/genetics
- DNA, Neoplasm/metabolism
- Disease Progression
- Genes, p53
- Genome
- Genome, Human
- Humans
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology
- Mutation
Collapse
Affiliation(s)
- B A Guinn
- Oncology Research Program, Toronto General Hospital, Ontario, Canada.
| | | |
Collapse
|
20
|
Abstract
Human herpesvirus 6 variant A (HHV-6A) and human herpesvirus 6 variant B (HHV-6B) are two closely related yet distinct viruses. These visuses belong to the Roseolovirus genus of the betaherpesvirus subfamily; they are most closely related to human herpesvirus 7 and then to human cytomegalovirus. Over 95% of people older than 2 years of age are seropositive for either or both HHV-6 variants, and current serologic methods are incapable of discriminating infection with one variant from infection with the other. HHV-6A has not been etiologically linked to any human disease, but such an association will probably be found soon. HHV-6B is the etiologic agent of the common childhood illness exanthem subitum (roseola infantum or sixth disease) and related febrile illnesses. These viruses are frequently active and associated with illness in immunocompromised patients and may play a role in the etiology of Hodgkin's disease and other malignancies. HHV-6 is a commensal inhabitant of brains; various neurologic manifestations, including convulsions and encephalitis, can occur during primary HHV-6 infection or in immunocompromised patients. HHV-6 and distribution in the central nervous system are altered in patients with multiple sclerosis; the significance of this is under investigation.
Collapse
Affiliation(s)
- D K Braun
- Eli Lilly, Lilly Corporate Center, Indianapolis, Indiana 46285, USA
| | | | | |
Collapse
|
21
|
Inoue R, Ushijima T, Katami M, Kushida H, Wakabayashi K, Sato H, Asamoto M, Katsuki M, Sugimura T, Nagao M. Rare activation of the human c-Ha-ras transgene of mice in hemangioendothelial sarcomas and liver tumors induced by Glu-P-1. Jpn J Cancer Res 1996; 87:583-8. [PMID: 8766521 PMCID: PMC5921135 DOI: 10.1111/j.1349-7006.1996.tb00263.x] [Citation(s) in RCA: 6] [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: 02/02/2023] Open
Abstract
A transgenic mouse (Tg), having the human c-Ha-ras proto-oncogene, has been demonstrated to develop hemangioendothelial sarcomas (HESs) which are associated with the transgene mutation, but not to develop liver tumors. In this study, we examined the effects of 2-amino-6-methyldipyrido [1,2-a:3',2'-d] imidazole (Glu-P-1), a food-borne carcinogen, which has been demonstrated to induce HESs and liver tumors in CDF1 mice, on Tg mice. Chronic administration of 0.05% Glu-P-1 in the diet induced HESs in Tg (7/17), but not in 18 non-transgenic mice (N-Tg). With basal diet, two out of 17 Tg but none of 22 N-Tg, developed HESs. In contrast, Glu-P-1 administration induced liver tumors, both in Tg and in N-Tg; 16/17 in Tg and 13/18 in N-Tg. The incidence of hepatocellular carcinomas in Tg was higher than that in N-Tg (8/17 versus 3/18). With basal diet, only one out of 17 Tg and none of 22 N-Tg developed liver tumors. The Ha-ras mutation in tumors developed by the groups administered Glu-P-1, was examined. No mutations were detected in the transgene and mouse c-Ha-ras genes in all three HESs examined. In contrast, when 29 liver tumors taken from Tg were examined, two mutations of the transgene were detected in two HCCs. No mouse c-Ha-ras gene mutations were detected in any of the 47 liver tumors examined, which had developed in Tg and N-Tg mice. These results suggest that the transgene plays a role in the development of HESs induced by Glu-P-1, but not as a result of its mutation. Further, the transgene plays no significant role in the development of liver tumors induced by Glu-P-1, but does play a role in the malignant conversion of some liver tumors, as a result of its mutation.
Collapse
Affiliation(s)
- R Inoue
- Carcinogenesis Division, National Cancer Center Research Institute, Tokyo, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Dieken ES, Epner EM, Fiering S, Fournier RE, Groudine M. Efficient modification of human chromosomal alleles using recombination-proficient chicken/human microcell hybrids. Nat Genet 1996; 12:174-82. [PMID: 8563756 DOI: 10.1038/ng0296-174] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Targeted modification of human chromosomal alleles by homologous recombination is a powerful approach to study gene function, but gene targeting in mammalian cells is an inefficient process. In contrast, gene targeting in a chicken pre-B cell line, DT40, is highly efficient. We have transferred human chromosome 11 into DT40 cells by microcell fusion, and find that the resulting hybrids are recombination-proficient. In these cells, targeting efficiencies into the chicken ovalbumin locus were > 90% and into the human beta-globin and Ha-ras loci were 10-15%. These modified human chromosomes can be transferred subsequently to mammalian cells for functional tests. This chromosome shuttle system allows for the efficient homologous modification of human chromosomal genes, and for subsequent phenotypic analyses of the modified alleles in different mammalian cell types.
Collapse
Affiliation(s)
- E S Dieken
- Division of Molecular Medicine, Fred Hutchinson Cancer Research Center, Seattle, Washington 98104, USA
| | | | | | | | | |
Collapse
|
23
|
Araujo JC, Doniger J, Kashanchi F, Hermonat PL, Thompson J, Rosenthal LJ. Human herpesvirus 6A ts suppresses both transformation by H-ras and transcription by the H-ras and human immunodeficiency virus type 1 promoters. J Virol 1995; 69:4933-40. [PMID: 7609062 PMCID: PMC189308 DOI: 10.1128/jvi.69.8.4933-4940.1995] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Human herpesvirus 6 strain U1102 (HHV-6A) was shown to contain a 1,473-bp functional transformation suppressor gene (ts). ts exhibited 24% identity and 51% similarity to adeno-associated virus type 2 Rep68/78. Like adeno-associated virus type 2 Rep68/78, HHV-6A ts suppressed H-ras transformation of NIH 3T3 cells. Suppression of H-ras transformation was eliminated by translation termination linker mutation at amino acid 25, 125, or 245. These data indicated the importance of the C-terminal portion of the ts protein. H-ras transformation was suppressed by ts only when H-ras was expressed by its endogenous H-ras promoter and not when it was expressed by the heterologous murine osteosarcoma virus long terminal repeat (LTR). Furthermore, ts suppressed chloramphenicol acetyltransferase (CAT) activity when the CAT gene was expressed from the H-ras promoter but not the murine osteosarcoma virus LTR promoter. Taken together, the data showed that ts suppressed H-ras transformation at the level of the H-ras promoter. To further identify the interaction of ts with transcriptional regulatory elements, the human immunodeficiency virus type 1 (HIV-1) LTR was used. This promoter was selected because it has well-defined transcriptional regulatory elements for both basal and activated transcription, because its activity is inhibited by the Rep68/78 gene, and because both HHV-6 and HIV-1 naturally infect CD4+ T cells in vivo and have been shown to infect the same cell in vitro. ts suppressed expression from both wild-type and upstream mutant HIV-1 LTR-CAT constructs. However, downstream HIV-1 TAR mutations reversed ts suppression, indicating that TAR is one of the critical elements involved. The data presented demonstrated that HHV-6A ts functionally suppressed H-ras transformation and HIV-1 LTR expression and thus that it may be useful in future gene therapy.
Collapse
Affiliation(s)
- J C Araujo
- Department of Microbiology and Immunology, Georgetown University Medical Center, Washington, D.C. 20007, USA
| | | | | | | | | | | |
Collapse
|
24
|
Zeidler W, Egle C, Ribeiro S, Wagner A, Katunin V, Kreutzer R, Rodnina M, Wintermeyer W, Sprinzl M. Site-directed mutagenesis of Thermus thermophilus elongation factor Tu. Replacement of His85, Asp81 and Arg300. EUROPEAN JOURNAL OF BIOCHEMISTRY 1995; 229:596-604. [PMID: 7758452 DOI: 10.1111/j.1432-1033.1995.tb20503.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
His85 in Thermus thermophilus elongation factor Tu (EF-Tu) was replaced by glutamine, leucine and glycine residues, leading to [H85Q]EF-Tu, [H85L] EF-Tu and [H85G]EF-Tu, respectively. Asp81 was replaced by alanine leading to [D81A]EF-Tu, and replacement of Arg300 provided [R300I]EF-Tu. Glycine in position 85 of domain I induces a protease-sensitive site in domain II and causes complete protein degradation in vivo. A similar effect was observed when Asp81 was replaced by alanine or Arg300 by isoleucine. Degradation is probably due to disturbed interactions between the domains of EF-Tu.GTP, inducing a protease-sensitive cleavage site in domain II. [H85Q]EF-Tu, which can be effectively overproduced in Escherichia coli, is slower in poly(U)-dependent poly(Phe) synthesis, has lower affinity to aminoacyl-tRNA but shows only a slightly reduced rate of intrinsic GTP hydrolysis compared to the native protein. The GTPase of this protein variant is not efficiently stimulated by aminoacyl-tRNA and ribosomes. The slow GTPase of [H85Q]EF-Tu increases the fidelity of translation as measured by leucine incorporation into poly(Phe) in in vitro poly(U)-dependent ribosomal translation. Replacement of His85 in T. thermophilus EF-Tu by leucine completely deactivates the GTPase activity but does not substantially influence the aminoacyl-tRNA binding. [H85L]EF-Tu is inactive in poly(U)-dependent poly(Phe)-synthesis. The rate of nucleotide dissociation is highest for [H85L]EF-Tu, followed by [H85Q]EF-Tu and native T. thermophilus EF-Tu. Mutation of His85, a residue which is not directly involved in the nucleotide binding, thus influences the interaction of EF-Tu domains, nucleotide binding and the efficiency and rate of GTPase activity.
Collapse
Affiliation(s)
- W Zeidler
- Laboratorium für Biochemie, Universität Bayreuth, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Telliez JB, Plumb M, Balmain A, Bailleul B. Regulatory elements in the first intron of the mouse Ha-ras gene. Mol Carcinog 1995; 12:137-45. [PMID: 7893367 DOI: 10.1002/mc.2940120305] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The Ha-ras gene is one of the three oncogenes (Ha-ras, Ki-ras, and N-ras) of the ras superfamily of small G proteins. The p21ras proteins encoded by the ras genes are key proteins involved in the transduction of signals from membrane receptor-tyrosine kinases to downstream targets. The ras genes seem to play a ubiquitous role in the control of cell proliferation and cell differentiation. At the same time, ras genes may perform specific differentiated functions in certain cell types. Little is known about the regulation of expression of the Ha-ras gene. The first intron of the Ha-ras gene has been reported to be highly conserved between human and rodent. We investigated the role that this intron may play in the regulation of expression of Ha-ras. The promoter region of the Ha-ras gene exhibits characteristics of a housekeeping gene. Deletion analysis shows the existence of an enhancer-type element in the 5' region of the first intron (intron 0). DNase 1 footprinting experiments reveal five sites that interact with nuclear proteins from fibroblast and epithelial cell lines. Deletion and site-directed mutagenesis of three of these sites show that two are involved in a positive effect and one in a negative effect on the regulation of expression of the mouse Ha-ras gene.
Collapse
Affiliation(s)
- J B Telliez
- INSERM Unite 124, Institut de Recherches sur le Cancer de Lille, France
| | | | | | | |
Collapse
|
26
|
Sato M, Nishigori C, Lu Y, Zghal M, Yagi T, Takebe H. Far less frequent mutations in ras genes than in the p53 gene in skin tumors of xeroderma pigmentosum patients. Mol Carcinog 1994; 11:98-105. [PMID: 7916998 DOI: 10.1002/mc.2940110207] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Mutations in Ha-ras, Ki-ras, and N-ras genes in squamous and basal cell carcinomas in patients with xeroderma pigmentosum (XP) were examined by the polymerase chain reaction followed by single-strand conformation polymorphism analysis and direct base sequencing. No mutation was detected in codons 12, 13, and 61 of the ras genes in XP skin tumors. This was in contrast with previous findings of a high frequency of mutation in the p53 gene in skin tumors in XP patients. A novel mutation in codon 6 of the Ki-ras gene was detected in a squamous cell carcinoma. The mutation was a C-->T transition at a dipyrimidine (5'-CT) sequence and could have been produced by solar ultraviolet light. The mutated ras gene did not have the ability to transform NIH/3T3 cells. In three tumors, multiple base substitutions were detected in exon 1 of the Ki-ras and N-ras genes. These results and our previous work on p53 gene mutations suggest that mutations in ras genes are far less frequent than in the p53 gene in the skin tumors in XP patients and that ras genes are less important in skin tumorigenesis in XP patients than is the p53 gene.
Collapse
Affiliation(s)
- M Sato
- Department of Experimental Radiology, Faculty of Medicine, Kyoto University, Japan
| | | | | | | | | | | |
Collapse
|
27
|
Chan AM, Miki T, Meyers KA, Aaronson SA. A human oncogene of the RAS superfamily unmasked by expression cDNA cloning. Proc Natl Acad Sci U S A 1994; 91:7558-62. [PMID: 8052619 PMCID: PMC44441 DOI: 10.1073/pnas.91.16.7558] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
As an approach to identify human oncogenes, we generated an expression cDNA library from an ovarian carcinoma line. A potent transforming gene was detected by transfection analysis and identified as TC21, a recently cloned member of the RAS gene superfamily. A single point mutation substituting glutamine for leucine at position 72 was shown to be responsible for activation of transforming properties. While the cDNA clone possessed high transforming activity, the ovarian tumor genomic DNA, which contained the mutated TC21 allele, failed to induce transformed foci. Thus, expression cDNA cloning made it possible to identify and isolate a human oncogene that has evaded detection by conventional approaches.
Collapse
Affiliation(s)
- A M Chan
- Laboratory of Cellular and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | | | | | | |
Collapse
|
28
|
Oka T, Matsunaga H, Tokunaga K, Mitsunaga S, Juji T, Yamane A. A simple method for detecting single base substitutions and its application to HLA-DPB1 typing. Nucleic Acids Res 1994; 22:1541-7. [PMID: 8202352 PMCID: PMC308027 DOI: 10.1093/nar/22.9.1541] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
We have developed a simple and reliable method, PCR-PHFA (polymerase chain reaction dependent preferential homoduplex formation assay), for detection of single base substitutions within PCR amplicons. This technique is based upon strand competition during hybridization between a double labeled amplicon, prepared from biotin and DNP labeled primers, and an unlabeled amplicon. Under the precisely controlled temperature gradient, the preferential formation of a homoduplex over a heteroduplex occurs. After annealing, the identical sequence of the double labeled and unlabeled amplicon resulted in a low population of regenerated double labeled dsDNA due to strand exchange between them. Even when the two differed by only a single base substitution, double labeled molecule was regenerated efficiently because of preferential homoduplex formation. The regenerated double labeled molecule was captured onto a streptavidin coated microtiter plate and quantified enzymatically with a chromogenic substrate. The technique has been successfully applied in HLA-DPB1 typing. Furthermore, we detected a mutated gene even in the presence of a large excess of the corresponding normal gene.
Collapse
Affiliation(s)
- T Oka
- Institute for Biotechnology Research, Wakunaga Pharmaceutical Co. Ltd., Hiroshima, Japan
| | | | | | | | | | | |
Collapse
|
29
|
Deng G, Eh Z, Xu Y, Lu Y. Activation of oncogene c-Ha-ras in gastric cancer of Chinese patients. SEMINARS IN SURGICAL ONCOLOGY 1994; 10:83-7. [PMID: 8052787 DOI: 10.1002/ssu.2980100204] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A transforming gene was cloned from a focus of rat fibroblast cell line Rat 1 transfected with DNA of a gastrocarcinoma cell line. The transforming gene is the activated form of oncogene c-Ha-ras, and the lesion was identified as a single nucleotide substitution at codon 12 by sequencing. We further used polymerase chain reaction (PCR)-restriction analysis to detect the mutations at codon 12 of c-Ha-ras. By using this method, 11 cases out of 24 solid tumors and 3 cell lines of gastric cancer were shown to contain mutations, and there was a strong correlation between mutations and metastasis and survival of the patients. The role of the activated c-Ha-ras in tumorigenesis of stomach cancer was further proved through the assay in which the malignant phenotypes of the c-Ha-ras-transformed cells were partially inhibited by blocking the c-Ha-ras expression with antisense oligonucleotides or exogenous plasmid expressing antisense RNA.
Collapse
Affiliation(s)
- G Deng
- Department of Biochemistry and Molecular Biology, Beijing Institute for Cancer Research, China
| | | | | | | |
Collapse
|
30
|
Kocabivik S, Perlin MH. Amino acid substitutions within the analogous nucleotide binding loop (P-loop) of aminoglycoside 3'-phosphotransferase-II. THE INTERNATIONAL JOURNAL OF BIOCHEMISTRY 1994; 26:61-6. [PMID: 8138049 DOI: 10.1016/0020-711x(94)90196-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
1. Oligonucleotide-directed mutagenesis of APH(3')-II was used to investigate the functions of key amino acids in the P-loop analogous motif of the enzyme. 2. The mutations of Gly205-->Glu, Gly210-->Ala and Arg211-->Pro considerably reduced the resistance of the resulting strains to KM and to related drugs, e.g. G418. 3. Similarly, enzyme activity in the crude extracts of these mutants was substantially reduced as well as the enzyme's affinity for Mg2+ ATP. 4. Alternatively substitutions at a highly conserved basic residue (Arg211-->Lys and Arg211-->His) were not sufficient for the enzyme to sustain the activity at a level comparable to that of the wildtype. 5. Moreover, an Arg211-->His mutation drastically reduced affinity of the enzyme for Mg2+ ATP. 6. This argues the importance of Arg211 residue in contributing to the formation of the P-loop structure in addition to its involvement in phosphoryl transfer reaction. 7. Computer analysis of the secondary structure predicted that the APH(3')-II loop connects a beta-strand to an alpha-helix and that the above mutations caused varying degrees of structural distortions at the corresponding regions of the protein.
Collapse
Affiliation(s)
- S Kocabivik
- Department of Biology, Middle East Technical University, Ankara, Turkey
| | | |
Collapse
|
31
|
Zhang PL, Calaf G, Russo J. Allele loss and point mutation in codons 12 and 61 of the c-Ha-ras oncogene in carcinogen-transformed human breast epithelial cells. Mol Carcinog 1994; 9:46-56. [PMID: 8297485 DOI: 10.1002/mc.2940090109] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
There is significant evidence that the ras oncogene plays a role in experimental mammary carcinogenesis; the evidence in human breast cancer, however, is more limited. We induced the expression of transformation phenotypes in the human breast epithelial cell line MCF-10F with the chemical carcinogens 7,12-dimethylbenz[a]anthracene, N-methyl-N-nitrosourea, N-methyl-N-nitro-N'-nitrosoguanidine, and benzo[a]pyrene. This work was designed to clarify whether chemically induced neoplastic transformation correlates with alterations in the ras gene. MCF-10F cells have two c-Ha-ras alleles, identified by 1.0-kb and 1.2-kb restriction fragments. Treatment with carcinogens resulted in the loss of one of the alleles (1.0 kb). Polymerase chain reaction-amplified DNA from all carcinogen-treated cells was analyzed for point mutations in c-Ha-ras at codons 12 and 61. All of the carcinogens induced a mutation of the remaining allele at the first position of codon 12 (GGC-->AGC). Another frequent mutation occurred at the first position of codon 61 (CAG-->GAG). The changes in c-Ha-ras were associated with the emergence of colony formation in agar-methocel, but no specific changes in this gene correlated with the emergence of invasiveness or tumorigenesis, indicating that other genes may be involved in the process.
Collapse
Affiliation(s)
- P L Zhang
- Department of Pathology, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111
| | | | | |
Collapse
|
32
|
Jahan I, Mihara K, Bai L, Namba M. Neoplastic transformation and characterization of human fibroblasts by treatment with 60Co gamma rays and the human c-Ha-ras oncogene. In Vitro Cell Dev Biol Anim 1993; 29A:763-7. [PMID: 8118610 DOI: 10.1007/bf02634342] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Human fibroblasts (KMST-6) immortalized by treatment with 60Co gamma rays were further neoplastically transformed by transfection of the c-Ha-ras oncogene from human lung cancer. The ras-transfected cells formed undifferentiated fibrosarcoma in nude mice. One of the tumors was recultured and a neoplastic human fibroblast line, KMST-6/RAS, was established. To analyze multistep carcinogenesis of human cells, the cellular characteristics of these genetically matched immortalized (KMST-6) and neoplastic (KMST-6/RAS) cell lines were studied in detail. KMST-6/RAS cells showed an increased saturation density, colony formation on confluent monolayers of normal human fibroblasts, proliferation in neomycin-containing medium, anchorage-independent growth, and enhanced expression of the transfected c-Ha-ras oncogene, whereas the immortalized cells did not demonstrate these characteristics. Unexpectedly, growth of KMST-6/RAS cells was serum-dependent, although they were neoplastic. Interestingly, the neoplastic cells did not show the criss-crossing or piling up growth pattern characteristic of transformed rodent fibroblasts.
Collapse
Affiliation(s)
- I Jahan
- Department of Cell Biology, Okayama University Medical School, Japan
| | | | | | | |
Collapse
|
33
|
Yaginuma Y, Fujita M, Saitoh S, Hayakawa K, Kuzumaki N, Ishikawa M. Immunohistochemical analysis of ras oncogene product p21 in human endometrial carcinoma. Acta Histochem 1993; 95:23-9. [PMID: 8279232 DOI: 10.1016/s0065-1281(11)80383-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Monoclonal antibody rp-28 directed against the ras gene product p21 has been used to evaluate ras p21 expression in endometrial lesions. Endometrial cancer showed a variable reactivity according to histological type: in well differentiated adenocarcinoma 63% were positive (12/19); in moderately differentiated adenocarcinoma 53% were positive (8/15); in poorly differentiated adenocarcinoma 40% were positive (2/5). The staining intensity of ras p21 seemed to be stronger in the more differentiated types of endometrial carcinoma. In endometrial carcinoma with premenopausal women, 27% were positive (3/11), and with postmenopausal women 71% were positive (20/28). The difference between premenopausal and postmenopausal groups was statistically significant (Mantel-Haenszel procedure, M-H chi 2 = 6.765, P < 0.01). The results suggest the existence of different carcinogenetic mechanisms in these two groups of endometrial cancer.
Collapse
Affiliation(s)
- Y Yaginuma
- Department of Obstetrics and Gynecology, Asahikawa Medical College, Japan
| | | | | | | | | | | |
Collapse
|
34
|
Pogrebniak HW, Matthews W, Black C, Russo A, Mitchell JB, Smith P, Roth JA, Pass HI. Targetted phototherapy with sensitizer-monoclonal antibody conjugate and light. Surg Oncol 1993; 2:31-42. [PMID: 8252191 DOI: 10.1016/0960-7404(93)90042-w] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Photodynamic therapy (PDT) was performed in vitro and in vivo using monoclonal antibody conjugated to hematoporphyrin (HP). The antibody (45-2D9) recognized a cell surface glycoprotein on cells derived from NIH 3T3 cells which were transformed with the ras oncogene (45-342). Radionuclide imaging with either In111 or I125 chelated to 45-2D9 or the isotype identical (IgG1) antibody MOPPC-21 revealed selectivity of 45-2D9 for 45-342 flank tumours in nude mice, and minimal targetting for a 45-342 clone which did not express the cell surface glycoprotein. The 45-2D9-HP conjugate resulted in selective killing of the 45-342 line compared with the parent line in vitro. At HP concentrations of 76 micrograms ml-1, the 45-2D9-HP conjugate resulted in significantly more long-term cures of PDT treated flank tumours compared with free HP at the same concentration. 45-2D9 alone had no effect on tumour growth. The antibody-HP conjugate resulted in significantly less local toxicity compared with standard Photofrin II PDT, and also achieved a greater number of long-term cures. This 'photoimmunotherapy' demonstrates the ability to treat established tumours with greater efficacy and decreased morbidity, probably due to specific sensitizer targetting which allows normal surrounding tissue to be spared upon illumination.
Collapse
Affiliation(s)
- H W Pogrebniak
- Thoracic Oncology Section, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | | | | | | | | | | | | | | |
Collapse
|
35
|
Iwamoto Y, Sugioka Y. Use of a reconstituted basement membrane to study the invasiveness of tumor cells. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1992; 324:141-9. [PMID: 1283496 DOI: 10.1007/978-1-4615-3398-6_14] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
We have used an extract of basement membranes which can be reconstituted into a biologically active gel matrix composed predominantly of collagen IV, laminin, nidogen, and heparin sulfate proteoglycan, in order to study the mechanisms involved in tumor cell invasion. When layered onto a porous filter in a Boyden chamber, the gel forms a barrier to the passage of normal cells. Malignant cells are able to cross this layer when the conditioned medium of NIH 3T3 cells is used as a chemoattractant to stimulate cell migration. A variety of human tumor cells have thus been studied in this system and we find a high correlation between their invasiveness in vitro and their malignant behavior as exhibited in vivo. We have used this in vitro invasion assay to test for factors which might inhibit tumor cell invasion. Collagenase IV is produced by malignant cells and is thought to be required for invasion. Indeed, inhibitors of this enzyme have demonstrated reduced tumor cell invasiveness. One site of five amino acids, on the B1 chain, which has been shown to promote cell adhesion, migration and binding to laminin receptor, was found to inhibit the invasion of tumor cells. In addition, factors which elevated cAMP levels were also able to suppress the invasiveness of tumor cells. These data suggest that the assay system described herein can be successfully utilized to study the invasive activity of tumor cells and those factors that may inhibit the spread of malignant cells.
Collapse
Affiliation(s)
- Y Iwamoto
- Department of Orthopaedic Surgery, Faculty of Medicine, Kyushu University, Fukuoka, Japan
| | | |
Collapse
|
36
|
Gonen B, Kahana O, Witz IP. In vivo tumorigenicity and in vitro sensitivity to tumor-necrosis-factor alpha mediated killing of c-Ha-ras-transformed cells. Cancer Immunol Immunother 1992; 35:388-94. [PMID: 1327528 PMCID: PMC11038314 DOI: 10.1007/bf01789017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/1992] [Accepted: 06/24/1992] [Indexed: 12/26/2022]
Abstract
Cellular subclones of high and low tumorigenicity obtained from a mouse c-Ha-ras-transformed clone, were examined for their sensitivity to tumor-necrosis-factor (TNF)-mediated cytotoxicity. Cells of the highly tumorigenic subclones showed a significantly enhanced resistance to the cytotoxic effect of TNF plus cyclohexamide (CHI) as compared to cells of the low-tumorigenic subclones. The enhanced resistance to TNF+CHI was not due to a lower expression of TNF receptors on the cells. The c-Ha-ras-transfected cells were transformed and maintained in culture only (C cells). In vivo passage of cells of the initially low-tumorigenic c-Ha-ras subclones through the mouse significantly enhanced the tumorigenic potential of these CTC cells (culture/tumor/culture). In correlation with their enhanced tumorigenicity, the CTC cells were highly resistant to TNF-mediated cytotoxicity as compared to C cells of the same subclone. Furthermore, the involvement of TNF in determining the tumorigenic phenotype of the c-Ha-ras-transformed cells was demonstrated in a more direct manner. Cells of a c-Ha-ras-transformed low-tumorigenic, highly TNF-sensitive subclone were selected by repeated cycles of in vitro exposure to TNF alpha. As a result, a stable, highly TNF-resistant population of cells emerged. These TNF-resistant cells caused more tumors in mice as compared to their original TNF-sensitive cells. These results show that the resistance to the cytotoxic effect of TNF plus cyclohexamide may be involved, at least partially, in the tumorigenic potential of c-Ha-ras-transformed cells and suggest a possible role for TNF in the enhancement of the tumorigenic potential of these cells in mice.
Collapse
Affiliation(s)
- B Gonen
- Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Israel
| | | | | |
Collapse
|
37
|
Anai T, Hasegawa K, Watanabe Y, Uchimiya H, Ishizaki R, Matsui M. Isolation and analysis of cDNAs encoding small GTP-binding proteins of Arabidopsis thaliana. Gene 1991; 108:259-64. [PMID: 1748311 DOI: 10.1016/0378-1119(91)90442-e] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We previously isolated a DNA fragment from Arabidopsis thaliana homologous to the mammalian ras gene and named it ara [Matsui et al., Gene 76 (1989) 313-319]. Screening of cDNA clones homologous to ara in A. thaliana resulted in the isolation of four homologous genes. The products of these genes, ARA-2, ARA-3, ARA-4 and ARA-5, showed conservation of amino acids (aa) in four regions, all of which are present in small GTP-binding proteins, and are important for GTPase/GTP-binding activities. These products were highly homologous to those of the YPT genes of Saccharomyces cerevisiae and the ypt gene of Schizosaccharomyces pombe in the regions around aa 45, which is thought to be the site interacting with effector molecules. The products of these four genes showed characteristic aa sequence at their C termini, Cys-Cys-Xaa-Xaa. Another characteristic of this family is presence of Ser in place of Gly in the first conserved region (Gly12 of mammalian GTP-binding Ras protein).
Collapse
Affiliation(s)
- T Anai
- Faculty of Science, Kagoshima University, Japan
| | | | | | | | | | | |
Collapse
|
38
|
McKenzie SJ. Diagnostic utility of oncogenes and their products in human cancer. BIOCHIMICA ET BIOPHYSICA ACTA 1991; 1072:193-214. [PMID: 1684291 DOI: 10.1016/0304-419x(91)90014-c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The first clear cut association of an oncogene with a specific cancer is the c-abl translocation in chronic myelogenous leukemia and acute lymphocytic leukemia; it has been observed in 90% of CML cases examined. This is the major contributing factor to its being the target of the first oncogene-based FDA-approved diagnostic test. Although the role of the abl translocation in the tumorigenic process is not yet understood, it is clear that somehow it must be causally related to the disease, and thus is an ideal target for a diagnostic test. The association of this oncogene with a specific cancer is the model on which all others may be based in the future. Second generation tests could easily include PCR on mRNA, and/or in situ hybridization, both of which could be performed using blood samples. Both methods would provide a faster means of testing a large number of cells, however, the methodologies must be improved through automation and computer-aided image analysis, respectively, in order to become useful routine tests. Both neu and epidermal growth factor receptor (EGFR) appear to have a close correlation between overexpression of the gene product and outcome of disease in breast cancer; valuable information for prognosis of the disease. And again, although the actual mechanism of action of these molecules and how this relates to the tumorigenic process is not yet known, it is believed from the very nature of the molecules that they must in some way contribute to the progression of the disease. In both cases, the protein products are overexpressed in tissue, and in the case of Neu, it appears as through at least some of the patients have a Neu-related protein in their serum. These molecules present relatively easy targets for the development of diagnostic/prognostic assays, as antibodies are easily made and can be incorporated into a variety of assay formats. Current assays available, an ELISA for Neu and a radio-ligand binding assay for EGFR, are highly sensitive, reproducible and relatively easy to perform. Only the ELISA is commercially available, however, and hence allows for easy comparison between laboratories. An abvious step towards the routine measurement of EGFR then is the development of a comparable commercially available test. An improvement for both types of assay would be the incorporation of an internal control to gauge the cellular component of the tissue samples that are tested. The outcome of the applications of myc and ras to cancer diagnostics is not so easily predictable, with a couple of exceptions.(ABSTRACT TRUNCATED AT 400 WORDS)
Collapse
Affiliation(s)
- S J McKenzie
- Applied bioTechnology, Inc., Cambridge, MA 02142
| |
Collapse
|
39
|
|
40
|
Lieu FM, Yamanishi K, Konishi K, Kishimoto S, Yasuno H. Low incidence of Ha-ras oncogene mutations in human epidermal tumors. Cancer Lett 1991; 59:231-5. [PMID: 1913619 DOI: 10.1016/0304-3835(91)90146-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Activation of the Ha-ras oncogene by point mutations has been suggested to play a role in animal skin carcinogenesis models. In this study, we investigated the significance of the Ha-ras mutations in human epidermal tumors. DNAs from paraffin-embedded tissues of benign and malignant human epidermal tumors (27 samples from 25 patients) were prepared and examined for point mutations of codons 12, 13 and 61 of Ha-ras gene by polymerase chain reaction and oligonucleotide hybridization. Only one sample of basal cell carcinoma and one sample of keratoacanthoma were found to carry an A to T transversion at the second position of codon 61. This low incidence of Ha-ras mutations suggests that the mutational activation of the gene may not be primarily involved in human epidermal tumorigenesis.
Collapse
Affiliation(s)
- F M Lieu
- Department of Dermatology, Kyoto Prefectural University of Medicine, Japan
| | | | | | | | | |
Collapse
|
41
|
Yura Y, Azuma M, Uchida K, Momose H, Oyasu R. ras gene alterations in invasive and non-invasive rat bladder carcinomas induced by N-methyl-N-nitrosourea. Br J Cancer 1991; 64:10-4. [PMID: 1854607 PMCID: PMC1977327 DOI: 10.1038/bjc.1991.231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
We have established a reliable method to induce invasive and non-invasive carcinomas in the heterotopically transplanted urinary bladder of rats by repeated injection of N-methyl-N-nitrosourea (MNU), and examined the alterations of the ras oncogenes and ras oncogene product (p21) in the induced tumours. The incidence of muscle-invasive carcinomas was proportional to the total dose of MNU. When 5, 6 or 12 doses of MNU were used, muscle invasive carcinomas developed in 22, 58 or 45% of animals, respectively, after a mean observation period, respectively, of 54 +/- 9, 45 +/- 13 and 38 +/- 3 weeks. Whereas activated H-ras gene was detected in only one non-invasive carcinoma by DNA transfection assay, seven of 18 non-invasive and invasive carcinomas showed activated ras p21 when examined by immunoblot analysis. Amplification or rearrangement of myc or epidermal growth factor (EGF) receptor gene was not observed. The results indicate that alterations of ras gene may be involved in the development of rat bladder carcinomas but not of invasiveness.
Collapse
Affiliation(s)
- Y Yura
- Department of Pathology, Northwestern University Medical School, Chicago, Illinois 60611
| | | | | | | | | |
Collapse
|
42
|
Abstract
Squamous, large cell, and adenocarcinoma, collectively termed non-small cell lung cancer (NSCLC), are diagnosed in approximately 75% of patients with lung cancer in the United States. The treatment of these three tumor cell types is approached in virtually identical fashion because, in contrast to small cell carcinoma of the lung, NSCLC more frequently presents with localized disease at the time of diagnosis and is thus more often amenable to surgical resection but less frequently responds to chemotherapy and irradiation. Cigarette smoking is etiologically related to the development of NSCLC in the great majority of cases. Genetic mutations in dominant oncogenes such as K-ras, loss of genetic material on chromosomes 3p, 11p, and 17p, and deletions or mutations in tumor suppressor genes such as rb and p53 have been documented in NSCLC tumors and tumor cell lines. NSCLC is diagnosed because of symptoms related to the primary tumor or regional or distant metastases, as an incidental finding on chest radiograph, or rarely because of a paraneoplastic syndrome such as hypercalcemia or hypertrophic pulmonary osteoarthropathy. Screening smokers with periodic chest radiographs and sputum cytologic examination has not been shown to reduce mortality. The diagnosis of NSCLC is usually established by fiberoptic bronchoscopy or percutaneous fine-needle aspiration, by biopsy of a regional or distant metastatic site, or at the time of thoracotomy. Pathologically, NSCLC arises in a setting of bronchial mucosal metaplasia and dysplasia that progressively increase over time. Squamous carcinoma more often presents as a central endobronchial lesion, while large cell and adenocarcinoma have a tendency to arise in the lung periphery and invade the pleura. Once the diagnosis is made, the extent of tumor dissemination is determined. Since most NSCLC patients who survive 5 years or longer have undergone surgical resection of their cancers, the focus of the staging process is to determine whether the patient is a candidate for thoracotomy with curative intent. The dominant prognostic factors in NSCLC are extent of tumor dissemination, ambulatory or performance status, and degree of weight loss. Stages I and II NSCLC, which are confined within the pleural reflection, are managed by surgical resection whenever possible, with approximate 5-year survival of 45% and 25%, respectively. Patients with stage IIIa cancers, in which the primary tumor has extended through the pleura or metastasized to ipsilateral or subcarinal lymph nodes, can occasionally be surgically resected but are often managed with definitive thoracic irradiation and have 5-year survival of approximately 15%.(ABSTRACT TRUNCATED AT 400 WORDS)
Collapse
Affiliation(s)
- D C Ihde
- Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | | |
Collapse
|
43
|
Tong LA, de Vos AM, Milburn MV, Kim SH. Crystal structures at 2.2 A resolution of the catalytic domains of normal ras protein and an oncogenic mutant complexed with GDP. J Mol Biol 1991; 217:503-16. [PMID: 1899707 DOI: 10.1016/0022-2836(91)90753-s] [Citation(s) in RCA: 196] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The biological functions of ras proteins are controlled by the bound guanine nucleotide GDP or GTP. The GTP-bound conformation is biologically active, and is rapidly deactivated to the GDP-bound conformation through interaction with GAP (GTPase Activating Protein). Most transforming mutants of ras proteins have drastically reduced GTP hydrolysis rates even in the presence of GAP. The crystal structures of the GDP complexes of ras proteins at 2.2 A resolution reveal the detailed interaction between the ras proteins and the GDP molecule. All the currently known transforming mutation positions are clustered around the bound guanine nucleotide molecule. The presumed "effector" region and the GAP recognition region are both highly exposed. No significant structural differences were found between the GDP complexes of normal ras protein and the oncogenic mutant with valine at position 12, except the side-chain of the valine residue. However, comparison with GTP-analog complexes of ras proteins suggests that the valine side-chain may inhibit GTP hydrolysis in two possible ways: (1) interacting directly with the gamma-phosphate and altering its orientation or the conformation of protein residues around the phosphates; and/or (2) preventing either the departure of gamma-phosphate on GTP hydrolysis or the entrance of a nucleophilic group to attack the gamma-phosphate. The structural similarity between ras protein and the bacterial elongation factor Tu suggests that their common structural motif might be conserved for other guanine nucleotide binding proteins.
Collapse
Affiliation(s)
- L A Tong
- Department of Chemistry, University of California, Berkeley 94720
| | | | | | | |
Collapse
|
44
|
Transforming activity of DNA from human esophageal cancer and the identification of the transforming gene. Chin J Cancer Res 1990. [DOI: 10.1007/bf02997554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
|
45
|
Abstract
This investigation has employed the NIH 3T3 cell transfection assay in an effort to detect transforming genes in DNA from squamous carcinomas of the head and neck. Of 11 tumor DNAs tested, 1 DNA sample from a gingival squamous carcinoma was able to produce primary and secondary transformants containing the human K-ras oncogene. This is the first report of an activated ras oncogene derived from a carcinoma of the head and neck. Head and neck cancers may possess activated ras oncogenes more often than is indicated by this study because of the relative inefficiency of transfection assays in detecting large transforming genes such as K-ras.
Collapse
Affiliation(s)
- R E Howell
- Department of Oral Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | | | | |
Collapse
|
46
|
Yuasa Y, Yamazaki H, Maruo K, Ueyama Y, Shibuya M, Tamaoki N. Alterations of mouse proto-oncogenes in sarcomas induced after transplantation of human tumors in athymic nude mice. Jpn J Cancer Res 1990; 81:333-9. [PMID: 2114387 PMCID: PMC5918048 DOI: 10.1111/j.1349-7006.1990.tb02572.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
During serial subcutaneous transplantation of several types of human tumors into nude mice, the local development of malignant mouse-specific sarcomas has been observed. Although the frequency of sarcoma induction is low, this phenomenon is very important because the mouse-specific sarcomas completely replaced the human tumors during serial transplantation. The DNA of five independently induced mouse-specific sarcomas was transfected into NIH/3T3 cells in order to detect oncogenes associated with mouse-specific sarcoma induction. Two of these DNAs were found to carry activated mouse c-N-ras and c-Ki-ras genes. The sequence analysis of the molecularly cloned mouse c-N-ras oncogene showed a single nucleotide transition from G to A at the 12th codon. This results in substitution of aspartic acid for glycine at this position. The mouse c-myc gene was also found to be amplified in a sarcoma. In these mouse sarcoma DNAs, human Alu sequences were not detected. These data strongly suggest that the mouse-specific sarcomas were not induced by the transfer of human transforming sequences but by the alterations of mouse proto-oncogenes.
Collapse
Affiliation(s)
- Y Yuasa
- Department of Hygiene and Oncology, Tokyo Medical and Dental University School of Medicine
| | | | | | | | | | | |
Collapse
|
47
|
Identification of lysine 15 at the active site in Escherichia coli glycogen synthase. Conservation of Lys-X-Gly-Gly sequence in the bacterial and mammalian enzymes. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(19)39943-0] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
|
48
|
Kato M, Toguchida J, Honda K, Sasaki MS, Ikenaga M, Sugimoto M, Yamaguchi T, Kotoura Y, Yamamuro T, Ishizaki K. Elevated frequency of a specific allele of the L-myc gene in male patients with bone and soft-tissue sarcomas. Int J Cancer 1990; 45:47-9. [PMID: 1967596 DOI: 10.1002/ijc.2910450110] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Restriction fragment length polymorphisms (RFLPs) of 2 oncogenes, c-Ha-ras and L-myc, have been analyzed in 101 patients with bone and soft-tissue sarcoma and in 98 normal individuals. The c-Ha-ras gene was highly polymorphic both in sarcoma patients and in normal individuals. In contrast to our previous observation in breast cancer patients (Honda et al., 1988), no significant difference in allele frequencies between normal and sarcoma populations was observed. The L-myc locus revealed 2-allele polymorphism, allele L (10-kb) and S (6.6-kb), after digestion with Eco RI. The allele frequencies of L and S in sarcoma patients were 0.381 and 0.619, respectively, and those in normal individuals were 0.485 and 0.515, respectively. While the distributions of alleles in both populations fitted well with the Hardy-Weinberg equilibrium, the frequency of the S allele was significantly higher in sarcoma patients than in normal individuals (p less than 0.05). When sarcoma patients were divided into male and female subpopulations, this difference was highly significant only in males (p less than 0.01) but not in females. Our results suggest that males carrying the S allele may be prone to develop sarcoma.
Collapse
Affiliation(s)
- M Kato
- Radiation Biology Center, Kyoto University, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
49
|
Affiliation(s)
- J R Broach
- Department of Biology, Princeton University, New Jersey 08544
| | | |
Collapse
|
50
|
Kiefer PE, Wegmann B, Bacher M, Erbil C, Heidtmann H, Havemann K. Different pattern of expression of cellular oncogenes in human non-small-cell lung cancer cell lines. J Cancer Res Clin Oncol 1990; 116:29-37. [PMID: 1690210 DOI: 10.1007/bf01612637] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Altered and deregulated cellular oncogenes were found in many human solid tumors. Except for a few types of tumors that consistently exhibited specific altered proto-oncogenes, the majority of tumors are associated with a number of transcriptionally activated cellular oncogenes. In the heterologous group of non-small-cell lung cancer (NSCLC), nothing about a specific pattern of proto-oncogene expression is known. Therefore, we investigated the expression of a panel of cellular oncogenes in NSCLC cell lines. DNA and RNA from 11 established NSCLC cell lines (4 adenocarcinoma cell lines, 3 squamous cell carcinoma cell lines, 3 large-cell carcinoma cell lines and 1 mesothelioma cell line) were isolated and analysed using the Southern, dot blot and Northern hybridization technique. c-myc RNA expression was found in all NSCLC cell line, L-myc expression only in 1 adenocarcinoma cell line, N-myc and c-myb expression in none of the 11 cell lines examined. No c-myc amplification could be detected in the DNAs. v-sis-related mRNA was observed in 5/11 cell lines without association to a specific NSCLC subtype. v-src-related mRNA, found in all tested cells, exhibited increased levels in 1 adenocarcinoma cell line (A-549) compared to the other cell lines. Binding sites for epidermal growth factor (EGF) had been described previously in NSCL, therefore we found erbB homologue transcripts coding for the EGF receptor in all NSCLC cell lines. Also, c-raf1-, N-ras-, Ki-ras-, and H-ras-related RNA expression was observed in all lines. We conclude that L-myc, N-myc, and c-myb expression does occur less frequently in NSCLC than in SCLC. Also amplification does not appear to be an important mechanism by which the c-myc proto-oncogene is activated in NSCLC. A specific pattern of oncogene expression could not be detected in NSCLC cells; each cell line examined showed its own pattern. However, transcriptional activation of a proto-oncogene like erbB, ras, raf, src, and c-myc, which are all involved in the progression pathway of EGF, may be a common feature of NSCLC.
Collapse
Affiliation(s)
- P E Kiefer
- Philipps-University Marburg/Department of Internal Medicine, Federal Republic of Germany
| | | | | | | | | | | |
Collapse
|