Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Amplification is one mechanism for activation of oncogenes and results in an excess of DNA template, which can lead to overproduction of oncogene-specific RNA and protein. Amplification of oncogenes has been observed in different tumor tissues. In certain cases amplification and overexpression of particular oncogenes have been correlated with tumor progression and clinical behavior. The best example is neuroblastoma in which the N-myc oncogene frequently is found to be amplified. Over 1,000 patients with breast cancer have been studied for amplification of the c-erbB-2 oncogene until now. The evidence from the studies that amplification of c-erbB-2 is correlated with poor prognosis is in our opinion not convincing. More and more investigations about oncogenes and disease prognosis will take place rather at the protein level than at the DNA level.
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PMID:Amplification of oncogenes and disease prognosis. 218 30

The neu gene in rat neuro/glioblastoma was found to be activated by a single point mutation in the DNA sequence encoding the transmembrane region of the neu-encoded p185 protein. The human homologue of the rat neu gene, termed c-erbB-2 or HER-2, can also be activated in vitro by a similar mutation in the corresponding region. Although the human neu gene was shown to be amplified/overexpressed in a large portion of human breast and ovarian cancer, no reports indicate that the human neu gene is activated by a point mutation in human tumor. To study the possible point mutation of neu gene in human tumors, we characterized the genomic structure in the transmembrane region of human neu gene, which in turn allowed us to determine DNA sequence in this region directly following DNA amplification by polymerase chain reaction. We analyzed 7 tumor cell lines (2 breast cancer, 1 neuroblastoma, 1 rhabdomyosarcoma, and 3 glioma) and 11 tumor tissue samples (8 breast and 3 ovarian cancers). No mutation was found in the transmembrane region of human neu gene. Our results suggest that unlike the rat neuro/glioblastoma, the single point mutation in the transmembrane region of the human neu gene is a rare event in human tumors. In this study, we developed a technique for direct DNA sequencing of the transmembrane region of the human neu gene. This technique makes it possible to screen a large number of tumor samples.
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PMID:Direct sequencing analysis of transmembrane region of human Neu gene by polymerase chain reaction. 220 83

To determine whether the amplification of the proto-neu oncogene (also called c-erbB-2) plays a role in tumorigenicity, we previously generated an NIH 3T3 transfectant (DHFR/G-8) that carried the amplified proto-neu gene. The DHFR/G-8 cells exhibited normal morphology. Their growth curve was similar to that of NIH 3T3 cells but was different from that of the B104-1 cell, and NIH 3T3 transfectant that carries the activated neu oncogene. When injected into nude mice, B104-1 cells produced tumors within 2 weeks, whereas the DHFR/G-8 cells did not produce tumors until 3 months after injection, and the NIH 3T3 cells did not produce any tumors even after 3 months. The tumors produced by the injection of the DHFR/G-8 cells were excised and grown in culture. The cells derived from the tumors were of transformed morphology and highly tumorigenic. The DNAs from the tumor cells were transfected into NIH 3T3 cells. The transfection resulted in foci on the NIH 3T3 monolayer. Southern analysis indicated that the foci derived from the transfection contained the neu gene. Using oligonucleotides as probes, the neu gene in the foci was found to carry a single-point mutation identical to the one previously found in the rat neuroblastoma and glioblastoma induced by the ethylnitrosourea. We conclude that the DNA region encoding the transmembrane domain of neu is a hot spot for converting the proto-neu gene into an activated oncogene and that amplification of the proto-neu gene facilitates mutation of the hot spot.
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PMID:Amplification of the proto-neu oncogene facilitates oncogenic activation by a single point mutation. 256 34

Alterations in the structure and/or expression of oncogenes have been examined to comprehend better the relationship between metastasis and oncogenes. There are reports that amplification and overexpression of N-myc (human neuroblastoma) and erbB-2 (human breast cancer) are closely related to malignant progression. On the other hand, DNA transfer experiments have also been done to assess involvement of oncogenes in metastasis. The active ras oncogenes, which are frequently used, show that transfer of the ras oncogenes endow and/or enhance the metastatic potential of the recipient cells. In addition to the phenomenological studies to determine whether an oncogene alters metastatic potential, increasing attention has been directed to possible phenotypic changes relating to metastasis and affected by oncogenes. It has been clarified that transfer of a certain oncogene, such as ras and fos, alters the expression of biomolecules, for example, metalloproteinases responsible for invasion, autocrine motility factors and cytoskeletal proteins related to cell motility, receptors of fibronectin for cell attachment, and histocompatibility antigens, such as H-2K and H2-D. While further characterization of the biomolecular changes induced by the oncogenes has to be done, the mechanisms of alteration in the expression and function of biomolecules directly involved in the metastatic potential also should be paid attention.
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PMID:[Cancer metastasis and oncogenes]. 267 90

Various kinds of lesions exist which should be discriminate from malignant or premalignant or borderline lesions. If there were a morphologic technical procedure on detection of malignant transformation of the cells at the initiation stage, before the lesion would develop a definitely identical with malignant lesion, such method must be most highly applicable for pathologists. DNA diagnosis has realized a warning of diagnosis of certain diseases or genetical maldevelopment prior to develop their clinical manifestation. Gene analysis has introduced in ++phragmatical screening test for certain diseases such as diabetes mellitus, thalassemia, T-cell leukemia or lymphoma, neuroblastoma, muscular dystrophy of Duchenne or Becker type, Ph' chromosome and so on. Immunohistochemical technology has provided an intracellular oncogene detection in some neoplastic malignancies such as n-myc in neuroblastoma. Amplification of c-erb B2 (also referred as neu and HER-2/neu) has indicated a higher malignant mammary carcinoma with poor-prognosis, even their size small and early stage. Oncogene analysis is expected to be available sperimposing on pathological morphology.
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PMID:[Detection of early stage cancer: pathological aspect with special reference to differential diagnosis]. 317 85

Neuroblastoma, a tumor of the sympathetic nervous system, is one of the most common solid malignancies in infants and represents 7% of all cases of childhood cancer outside of the central nervous system. Thirty-five samples of neuroblastoma from 31 patients were obtained from Duke University Medical Center between 1979 and 1991 and studied to determine the relative prognostic value of a number of clinical, histologic, nuclear, and oncogenic features. The features studied were: stage, Shimada classification, DNA ploidy, MIB-1-proliferation index and status for HER-2/neu, p53 and epidermal growth factor receptor (EGFr). Only age (P = .03), HER-2/neu (P = .01), and p53 (P = .02) reached statistical significance as prognostic indicators. The median survival for patients with HER-2/neu expression was 12 months; median survival for patients with no HER-2/neu expression was 138 months. Similarly, the median survival for patients with p53 expression was 12 months; patients with no p53 expression had a median survival was 144 months. The combination of either HER-2/neu or p53 positivity was especially strong as a prognostic indicator (P = .002).
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PMID:Prognostic indicators for neuroblastoma: stage, grade, DNA ploidy, MIB-1-proliferation index, p53, HER-2/neu and EGFr--a survival study. 774 72

Activation of cellular or c-oncogenes and loss of function of suppressor genes appears to be the key event in the formation of most human cancers. Altered forms of these genes or their protein products have the potential to provide a new generation of cancer markers. As cancer markers, the most useful application of c-oncogenes and suppressor genes so far, has been in providing prognostic information. The correlation of N-myc gene amplification with poor prognosis in neuroblastoma was one of the first examples of prognostic data supplied by a c-oncogene. Most, but not all investigators, find that either amplification or increased expression of c-erbB-2 gene correlates with poor prognosis in breast cancer. Other potential prognostic markers in breast cancer include amplification of the c-myc gene, and increased expression of both EGFR and p53 protein. Although c-oncogenes and suppressor genes have the potential to supply prognostic information in a broad range of cancers, many of the results are still preliminary with conflicting conclusions.
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PMID:Cellular oncogenes and suppressor genes as prognostic markers in cancer. 812 58

Twenty-four advanced (surgical stage III and IV) ovarian carcinomas and 15 borderline ovarian tumours were studied for the overexpression of nm23 and HER-2/neu (c-erb-B2) by means of immunohistochemistry on sections from routinely processed, paraffin-embedded, archival tumour blocks, using the NCL-nm23 and the NCL-CB11 monoclonal antibodies and the streptavidin-biotin-peroxidase technique. Significantly more advanced ovarian carcinomas (p = 0.034) expressed high levels of nm23 when compared to borderline tumours. HER-2/neu (c-erb-B2) expression, as could be expected, was also significantly more frequent in advanced ovarian carcinomas (p = 0.006). We were not able to find the previously reported association between nm23 and HER-2/neu overexpression in our tumours. Our results on nm23 overexpression in ovarian cancer are coincident with those previously reported using nm23-mRNA measurements on fresh ovarian tissues. Thus, ovarian carcinoma seems to belong to the group of tumours, like colon carcinoma and neuroblastoma, in which nm23 overexpression is associated with a more malignant phenotype. Immunohistochemistry performed on archival samples from ovarian carcinomas seems adequate for the demonstration of nm23 overexpression in ovarian cancer. This opens the possibility for larger studies on series of patients with a closed follow-up, which could help to establish the role of this gene in this kind of tumour.
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PMID:nm23 expression in advanced and borderline ovarian carcinoma. 870 36

Comparative genomic hybridization (CGH) was applied to 35 neuroblastomas to obtain a global view of genetic imbalances. Results were validated by means of Southern blot hybridization (detection of N-myc amplification), loss of heterozygosity (LOH) studies (detection of deletion 1p), and interphase cytogenetics [dual labelling fluorescence in situ hybridization (FISH) of centromeric 17 and erbB-2]. CGH allowed sensitive detection of N-myc amplification and chromosome 1p deletion, representing the most established prognostic markers of neuroblastoma. In addition, a high rate of chromosome 17 aberrations (63 per cent) with possible prognostic relevance was observed. Previously unreported high level copy number increases indicating oncogene amplification were mapped to chromosome subbands 2p13-14 and 3q24-26. Other recurrent regional chromosomal aberrations were localized on 11q, 12q, 13q, 14q, and 15q. CGH results were fully consistent with data of Southern blot analysis and LOH study, as well as interphase cytogenetics. These results show that CGH is a sensitive method for the detection of all prognostically relevant genetic alterations in neuroblastomas; that CGH considerably simplifies the detection of these alterations, resulting in a single methodological approach; and that CGH is a powerful tool to elucidate previously unknown genetic changes in neuroblastomas.
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PMID:Comparative genomic hybridization (CGH) analysis of neuroblastomas--an important methodological approach in paediatric tumour pathology. 919 36

The biodistribution of 11C-labeled 4-(3-bromoanilino)-6,7-dimethoxyquinazoline, an inhibitor of the epidermal growth factor (EGF) receptor tyrosine kinase, has been evaluated in vivo in rats using positron emission tomography (PET). Time-activity data obtained after i.v. administration in one rat revealed that the radiotracer rapidly cleared from plasma with subsequent uptake in major organs of the body (brain, heart, liver, gastrointestinal tract and bladder). Uptake in proliferating tissue in rats with human neuroblastoma xenografts indicate that [O-11C-methyl]PD153035 shows promise as a new agent for in vivo imaging of tumors with PET.
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PMID:In vivo evaluation of the biodistribution of 11C-labeled PD153035 in rats without and with neuroblastoma implants. 1041 22


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