Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0178874 (tumor progression)
 40,807 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The determination and comparison of genotypic combinations at genomic loci in constitutional and tumor tissues from patients with various types of cancer have defined the chromosomal locations of loci in which recessive mutations play a role in disease development. The predisposing nature of some of these mutant alleles is exemplified by studies of retinoblastoma and osteogenic sarcoma, two clinically associated diseases that share a pathogenetically causal predisposition mapping to 13q14. Genomic alteration of chromosome 10 is apparent in glioblastomas and mixed tumors of glioblastoma/astrocytoma grade III but not in homogeneous astrocytoma grades II or III; this suggests the definition of a locus involved in tumor progression and, perhaps, an approach to molecular genetic staging of tumors.
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PMID:Loss of heterozygosity in stages of malignancy. 266 35

The role of chemotherapy in the treatment of retinoblastoma (RB) is unsatisfactory and clinical research is severely limited. A xenograft model for testing chemotherapeutic and other agents has been developed by the heterotransplantation of human RB cells into the anterior chamber of the nude mouse eye. A grading system for visually monitored tumor growth was designed to allow serial observations and documentation of the response to therapy in the model. This method of monitoring compared favorably with histopathologic, photographic, or other criteria in the reproducible, sequential evaluation of tumor status. Six chemotherapeutic agents [vincristine (VCR), doxorubicin (DOX), actinomycin D (ACT-D), dimethyltriazeno-imidazole carboxamide (DTIC), cyclophosphamide (CPM), and diaziquone (AZQ)] were then tested in the model against a patient-derived xenograft line. Results were expressed as the delay in tumor progression judged by serial grading. CPM produced a consistent response in all treated tumors, as did DTIC to a lesser, more variable extent. In 3 of 10 tumors treated with CPM and in 1 of 18 treated with DTIC, complete responses were maintained for at least 20 weeks. VCR, DOX, and ACT-D were ineffective, producing patterns of tumor progression no different from those in the control group. AZQ was most effective, producing responses far exceeding those of conventional agents. The model allows quantitative documentation of the response to therapy in heterotransplanted human RB. Further testing of new agents and combinations is warranted. AZQ may be active against RB.
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PMID:Evaluation of response to chemotherapy in retinoblastoma heterotransplanted to the eyes of nude mice. 291 May 12

Isochromosome (6p) represents a highly characteristic cytogenetic abnormality of human retinoblastoma (RB) cells and may be important for tumor progression. To elucidate the mechanism by which this abnormal chromosome is formed, 24 RB tumors and three cell lines were studied by means of DNA polymorphisms specific for the short arm and the long arm of chromosome 6. Our results indicate that mitotic nondisjunction leading to trisomy 6 precedes the isochromosome formation. The isochromosome may then be formed by transverse division of the centromere or intrachromosomal chromatid exchange.
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PMID:Mechanism of i(6p) formation in retinoblastoma tumor cells. 291 37

Normal skin fibroblasts from patients genetically predisposed for cancer express certain phenotypic properties usually associated with transformed cells, suggesting that these cells are engaged in a cancer progression process. Previously, we have shown that a subgenomic fraction, which we called Ta DNA ('tumor-activated DNA') was preferentially expressed in all human tumor cells (Hanania et al., Proc. Natl. Acad. Sci. U.S.A., 78 (1981) 6504-6508; Hanania et al, EMBO J., 2 (1983) 1621-1624). Here, we show that Ta DNA transcripts are present in Fanconi's anemia (FA) and retinoblastoma (Rb) fibroblasts, at a level hardly lower than in tumor cells. In contrast, a few Ta DNA transcripts can be detected in normal cells.
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PMID:An abnormal expression of a tumor-activated multigenic set in cells from cancer prone patients with inherited Fanconi's anemia (FA) and retinoblastoma (Rb). 335 23

Neoplastic diseases are characterized by uncoordinated cell growth. Cellular proliferation follows an orderly progression through the cell cycle, which is governed by protein complexes composed of cyclins and cyclin-dependent kinases. These complexes exert their regulatory function by phosphorylation of key proteins involved in cell cycle transitions, such as the product encoded by the retinoblastoma gene (pRB). Mutations and overexpression of cyclins and cyclin-dependent kinases, mainly cyclin D1 and Cdk4, have been reported and proposed to be oncogenic events. More recently, a new family of negative regulators functioning as Cdk-inhibitory molecules has been identified. Because of their recessive nature in cell cycle control and the fact that some of them are mutated in human tumors, it has been suggested that they may also function as tumor suppressor genes. It appears that the molecular networking of these proteins and complexes impact on two fundamental cell cycle regulators: p53 and pRB. Cross-talk pathways between these two nuclear proteins are being delineated, implying potential links between p53 and pRB in cell cycle control, apoptosis, and tumor progression. In addition, the high rate and mutation pattern of TP53 and RB in primary tumors have rendered them prototype tumor suppressor genes. Furthermore, detection of TP53 and RB mutations and altered expression of their encoded products appear to be of clinical significance, often correlating with prognosis, when identified in specific cancers. Based on these findings, new strategies are being developed in the emerging field of gene replacement-therapy.
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PMID:Mutations of cell cycle regulators. Biological and clinical implications for human neoplasia. 767 68

The reactivity of a mAb (M16) raised against a small cell lung carcinoma line is described. M16 identifies a surface antigen expressed on cells of neuroectodermal origin following activation, as well as neoplastic transformation. M16 antigen expression is increased on retinoblastoma and neuroblastoma cell lines upon 'in vitro' stimulation and it is induced 'in vivo' on glial cells activated following brain injury. Furthermore, glial tumors show levels of M16 molecule expression increasing with the degree of malignancy, and in a retinoblastoma cell line, the expression of M16 was inversely related to the level of HLA-Class I and N-CAM antigens. The M16 antigen may represent a marker of both activation and neoplastic progression for neuroectodermal cells.
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PMID:Biochemical characterization and membrane expression of an antigen shared by activated and neoplastic cells of neuroectodermal origin. 770 33

Analysis of bovine interphotoreceptor matrix and conditioned medium from human Y-79 retinoblastoma cells by gelatin SDS-PAGE zymography reveals abundant activity of a 72-kDa M(r) gelatinase. The 72-kDa gelatinase from either source is inhibited by EDTA but not aprotinin or NEM, indicating that it is a metalloproteinase (MMP). The 72-kDa MMP is converted to a 62-kDa species with APMA treatment after gelatin sepharose affinity purification, typical of previously described gelatinase MMP-2. The latent 72-kDa gelatinase from either bovine IPM or Y-79 media autoactivates without APMA in the presence of calcium and zinc after 72 hr at 37 degrees C, producing a fully active mixture of proteinase species, 50 (48 in Y-79 medium), 38 and 35 kDa in size. The presence of inhibitory activity was examined in both whole bovine IPM and IPM fractions separated by SDS-PAGE. Whole IPM inhibited gelatinolytic activity of autoactivated Y-79-derived MMP in a dose-dependent manner. Inhibitory activities are observed in two protein fractions of 27-42 and 20-25 kDa. Western blots using antibodies to human tissue inhibitor of metalloproteinase 1 and 2 (TIMP-1 and -2) reveal the presence of two TIMP-1-like proteins at 21 and 29 kDa in inhibitory fractions of the bovine IPM. TIMP-2 was not detected in the inhibitory IPM fractions, consistent with the observed autoactivation of bovine IPM 72-kDa gelatinase. Potential roles for this IPM MMP-TIMP system include physiologic remodelling of the neural retina-RPE cell interface and digestion of shed rod outer segment as well as pathological processes such as retinal detachment, PE cell migration, neovascularization and tumor progression. Cultured Y-79 cells appear to be a good model for studying the production and regulation of this proteinase system.
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PMID:Characterization and novel activation of 72-kDa metalloproteinase in retinal interphotoreceptor matrix and Y-79 cell culture medium. 782 70

Molecular and genetic analyses of tumor cell show that cellular oncogenes and suppressor genes are involved in neoplastic transformation. In pediatric tumors oncogenes as N-myc play an important role in the tumor progression. In retinoblastoma, neuroblastoma, Wilms' tumor, and rhabdomyosarcoma loss of heterozygosity for specific chromosome loci has been suggested to be a critical step in cancer development. Oncogene abnormalities can also be useful as a molecular tumor factor to foresee the prognosis of the disease. The present article is a review on the role of the oncogenes and suppressor genes in pediatric solid tumors.
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PMID:[Oncogenes and suppressor genes in the genesis and progression of solid tumors in children]. 797 41

Our recent allelic analysis of head and neck squamous cell carcinomas identified a high incidence of chromosomal loss on 13q. To further define an area of minimal loss, we tested 60 primary head and neck squamous cell carcinomas in 59 patients for loss of heterozygosity (LOH) by using 10 polymorphic microsatellite markers spanning the long arm of chromosome 13. We examined the same primary tumors for inactivation of the retinoblastoma (Rb) gene by immunohistochemical analysis of paraffin-embedded specimens. Thirty-one of 60 (52%) tumors demonstrated LOH in at least one 13q marker. Twenty-nine of 31 (94%) lost a portion of 13q that included D13s133, which lies just telomeric to the Rb gene at 13q14.3. However, immunohistochemical staining revealed absence of Rb protein in only 6 of these 31 tumors (19.4%) with LOH. All but one tumor without LOH on 13q displayed normal Rb protein staining. Although Rb may be inactivated by an unusual mechanism in some head and neck squamous cell carcinomas, our data suggest that another tumor suppressor gene locus at 13q14 is likely to be involved in head and neck tumor progression.
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PMID:Infrequent inactivation of the retinoblastoma gene despite frequent loss of chromosome 13q in head and neck squamous cell carcinoma. 806 50

The nuclear phosphoprotein encoded by the retinoblastoma gene (pRB) appears to play a central role in control of cell division and differentiation. It is generally accepted that pRB is ubiquitously expressed. We investigated the expression of pRB in normal human tissues using immunochemical techniques to determine the expression of pRB in specific cell types. Maturing cells, both proliferating and nonproliferating, rather than their progenitors possess the highest levels of pRB. Cells of stratified epithelia, such as those from cervix, display strong immunostaining in the nondividing maturing suprabasal layer, whereas basal cells showed low to undetectable levels of pRB. Similar patterns of expression were observed in simple epithelia and hematopoietic cells contained within distinguishable proliferating compartments and in germ cell development. These studies are crucial to our understanding of processes involved in control of differentiation (tumorigenesis) as well as tumor progression.
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PMID:Expression of the retinoblastoma protein is regulated in normal human tissues. 812 35


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