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)

Expression of the endothelial adhesion molecule VCAM-1 was studied in human malignant melanoma lines by flow cytometry. Clones 2/4 and 2/14 (derived from the same lesion) had appreciable levels of VCAM-1 expression, whereas clone 2/21 and the lines A2058, Mel24, and A375 were negative. Clone 2/14 was selected for further analysis. Exposure to tumor necrosis factor (TNF) markedly augmented VCAM-1 on melanoma cells. Surface VCAM-1 was associated with expression of specific transcripts that were augmented by TNF. Analysis by reverse transcriptase and polymerase chain reaction using appropriate primers revealed that TNF-stimulated melanoma cells expressed both 7 and 6 immunoglobulin domain transcripts with predominance of the longer species. Tumor necrosis factor--stimulated melanoma cells bound more VLA-4-expressing cells (melanoma and monocytes) than resting tumor cells and anti-VCAM-1 monoclonal antibodies significantly inhibited binding, thus suggesting that surface VCAM-1 on melanoma is functional. Analysis of melanoma tissue sections demonstrated that VCAM-1 is not a marker of transformation of melanocytes because it can be detected in benign nevi. Although, unlike ICAM-1, VCAM-1 is not correlated with tumor progression, its expression in a fraction of primary melanomas indicates that it may play a role in regulating host immune response and homotypic interactions in some malignant melanomas.
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PMID:Regulated expression of vascular cell adhesion molecule-1 in human malignant melanoma. 128 17

The reactivity of four monoclonal antibodies (MAbs) directed against IFN-gamma inducible antigens with melanocytic cells was investigated in the course of local and systemic tumor progression of human malignant melanoma. Frozen sections of histologically defined melanocytic tissues at different stages of progression were stained with these MAbs using an indirect immunoperoxidase technique. The reactivity of MAbs Me15/B3 and Me15/F9, directed against two different epitopes of a 90-kDa molecule, was found to correlate with melanoma progression. Indeed, a significantly lower percentage of small than of advanced primary melanomas or metastases stained positively. A differential staining of nevocytic and dysplastic nevi was further observed for these two MAbs, which were also non-reactive with normal skin melanocytes. The reactivity of MAb Me14/D12, which identifies the intercellular adhesion molecule ICAM-1 and MAb Mel14/F12, directed against a 40-kDa molecule, was found to be independent of the Breslow thickness of primary melanomas. Both the latter MAbs stained a high proportion of nevocytic and dysplastic nevi. The co-expression of the surface molecules defined by MAbs Me14/D12, Me15/B3 and Me15/F9 in the course of melanoma progression was also analyzed. The frequency of this co-expression increased according to the Breslow thickness of primary melanomas. In addition, up to 100% of metastases, as opposed to 20% of dysplastic nevi, were found to be simultaneously stained by these three MAbs. It is therefore conceivable that high-risk melanocytic lesions might be identified by the use of a combination of MAbs directed against IFN-gamma regulated antigens.
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PMID:The differential reactivity of cells of the melanocytic lineage with four monoclonal antibodies against IFN-gamma inducible molecules. 134 19

The 89-kDa cell surface glycoprotein, P3.58, is detectable on advanced human melanomas in situ but not on benign melanocytes or early melanomas. cDNA cloning of P3.58 from melanoma cells was accomplished by screening a lambda zap expression vector library with monoclonal antibodies produced against the denatured antigen. Nucleotide sequencing of the clones revealed that P3.58 is identical to the intercellular-adhesion molecule 1. No qualitative differences in P3.58 mRNA species could be seen between melanoma cells and hematopoietic cells and no differences in gene organization were observed between peripheral blood leukocytes and melanoma cells. Inspection of the deduced amino acid sequence of P3.58 indicated the presence of the consensus sequence characteristic for complement-binding proteins. The acquisition of this cell-adhesion molecule during the process of tumor progression is speculated to contribute to the development of metastasis in melanoma.
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PMID:De novo expression of intercellular-adhesion molecule 1 in melanoma correlates with increased risk of metastasis. 264 20

Expression of carbohydrate ABH blood group antigens is oncodevelopmentally regulated and their presence on tumor cells constitutes a prognostic factor. However, it is not clear whether they directly affect tumor behavior. Using a rat model of colon carcinoma, we previously observed an association between the presence of H blood group antigens and tumorigenicity in syngeneic animals. In the present study, we show by immunoprecipitation experiments that cell surface H blood group antigens of a highly tumorigenic clone (PROb) are essentially carried by splice variants of the CD44 molecule containing exon V6. PROb cells were then transfected with an antisense fragment of the gene coding for a rat alpha (1-2)fucosyltransferase. This enzyme allows synthesis of H antigens from various beta-galactoside precursors. Transfected subclones of PROb cells were obtained which had significantly decreased enzymatic activity and H antigenic cell surface levels. In contrast, no such changes were observed in control cells transfected with either the empty vector or with a sense fragment of the gene. Compared to controls, the antisense-transfected cells were far less tumorigenic in syngeneic animals. These results show that H blood group antigens at the surface of PROb colon carcinoma cells contribute to tumor progression. The presence of the fucosylated structures on CD44 could modulate the functions of this adhesion molecule.
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PMID:H blood group antigen carried by CD44V modulates tumorigenicity of rat colon carcinoma cells. 752 57

In this study, we examined the expression of c-fos, c-myc, mutant c-Ha-ras and mutant p53 proteins in three normal human melanocyte cell lines and the following 12 melanoma cell lines: M5, Mewo, A375, Bro, Mel 2a, O-Mel II, IgR 39, SkMel-13, -19, -28 Mel-57 and NKI-4, using an immunohistochemical assay (APAAP). An effort was made to correlate oncogene expression with growth parameters, differentiation antigens (HMB-45, vla-2, k.1.2.58, HLA-DR, HLA-I), and pigmentation. All melanocyte cell lines were negative for the oncogenes examined, whereas six of the melanoma cell lines were found also positive (three for c-fos, two for c-myc, one for c-Ha-ras, and four for p53). Three melanoma cell lines expressed one oncogene and three the combination c-fos/p53. These three melanoma cell lines were positive for the "late" tumor progression marker A. 1.43 (vla-2 adhesion molecule) and negative for the differentiation marker k. 1. 2. 58. Positivity for A. 1. 43 combined with negative staining for k. 1. 2. 58 was found in six out of the 12 cell lines. The observed oncogene expression correlated neither with growth parameters nor melanin content. The present findings revealed a coexpression of mutant p53 and c-fos proteins being associated with a highly malignant phenotype in melanoma cell lines. Further studies are necessary to clarify the significance of the above findings.
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PMID:P53 mutation and c-fos overexpression are associated with detection of the antigen VLA-2 in human melanoma cell lines. 788 7

Down-regulation of E-cadherin, an intercellular adhesion molecule, and up-regulation of autocrine motility factor receptor (gp78) expressions have been shown to play a role in tumor cell invasion and metastasis. Monoclonal antibodies against E-cadherin and gp78 were used to stain serial snap-frozen sections of 12 normal bladder and 83 bladder carcinoma specimens (27 noninvasive, 53 invasive, and 3 metastases). In normal urothelium, E-cadherin is expressed while gp78 is not. Positive expression of E-cadherin and negative expression of gp78 were found to be associated with a low risk of clinical progression in the superficial bladder carcinoma patient group. While reduction in E-cadherin concomitantly with an increase in gp78 expression was associated with poor prognosis, 71% of the patients (n = 30) underwent rapid cancer progression, and 32% of the patients died of cancer-related disease at a median of 2 years after initial diagnosis. Thus, it is suggested that reduction of E-cadherin expression associated with an increase in the level of gp78 in bladder cancers may define a high risk group of patients. The dual use of these two antigens may improve early diagnosis of high risk bladder cancer patients and influence treatment decisions.
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PMID:Inverse relation of E-cadherin and autocrine motility factor receptor expression as a prognostic factor in patients with bladder carcinomas. 820 27

To investigate the cellular mechanisms of ovarian epithelial carcinogenesis, a series of progressively transformed rat ovarian surface epithelial (ROSE) cell lines were developed and studied. Transfection of primary ROSE cells and an immortalized ROSE line (ROSE 199) with the pSV3neo plasmid (SV40 T-antigen) yielded transformed lines which retained epithelial morphology. In vivo selection of these pSV3neo cell populations resulted in further phenotypic transformation. Transfection of ROSE 199 with pSV2neo/c-H-rasEJ (rasEJp21) resulted in a malignant line which appeared fibroblast-like and formed invasive sarcomas both in athymic mice and in immunocompetent rats. Gap junctional intercellular communication (GJIC) and cell-cell adhesion were studied in this series of ROSE lines. Both c-H-rasEJ-transformation and in vivo selection resulted in a significant reduction of GJIC between adjoining cells and a transition of in vitro migration as continuous epithelial sheets to the dissociation of individual cells. This apparent shift in cell adhesiveness was associated with reduced expression of the E-cadherin adhesion molecule. Our data suggest that neoplastic progression of the ovarian surface epithelium may be associated with concomitant reductions in GJIC, E-cadherin expression and functional adhesiveness.
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PMID:An in vitro model of ovarian epithelial carcinogenesis: changes in cell-cell communication and adhesion occurring during neoplastic progression. 832 8

The cell surface glycoprotein MUC18, a member of the immunoglobulin superfamily and homologous to several cell adhesion molecules, is associated with tumor progression and the development of metastasis in human malignant melanoma. Immunohistochemical and Northern blot analysis revealed that expression of the antigen is restricted to advanced primary and metastatic melanomas and to cell lines of the neuroectodermal lineage. The genomic sequence encoding the cell surface antigen spans approximately 14 kb and consists of 16 exons. The organization of the gene, which is related to that of the neural cell adhesion molecule N-CAM, shows a structure where each immunoglobulin-related domain is encoded by more than one exon. Sequencing of the putative MUC18 promoter region revealed a G + C-rich promoter lacking conventional TATA and CAAT boxes. Several motifs for binding of transcription factor Sp1 are present in the regulatory region, and only a single transcription start site within a presumed initiator sequence was identified. Sequence elements which might confer melanocyte-specific expression were not detected. Instead, recognition sequences for the transcription factors CREB, AP-2, and c-Myb, as well as CArG-box motifs, were observed. These elements may contribute to the differential regulation of the MUC18 gene in normal and malignant tissues and suggest a role for this putative adhesion molecule in neural crest cells during embryonic development.
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PMID:Genomic organization of the melanoma-associated glycoprotein MUC18: implications for the evolution of the immunoglobulin domains. 837 24

Carcinogenesis requires a complex series of genetic changes often involving multiple oncogenes and the inactivation of multiple tumor-suppressor genes. We presently examined the effect of the Krev-1 tumor-suppressor gene on the tumorigenic and metastatic potential of Ha-ras-transformed cloned rat embryo fibroblast (CREF) cells. Ha-ras-transformed CREF cells are morphologically transformed and anchorage independent; produce reduced levels of nm23-H1 (a putative metastasis-suppressor gene product) and TIMP-1 (tissue inhibitor of metalloproteinase 1) transcripts and mRNA compared with CREF cells; produce increased levels of cripto, 94-kDa gelatinase/type IV collagenase (94-kDa GEL), osteopontin (OPN) and transin/stromelysin transcripts and mRNA compared with CREF cells; and are tumorigenic and metastatic in both nude mice and syngeneic rats. Ha-ras-transformed CREF cells coexpressing the Krev-1 gene display a reversion in cellular phenotype and gene expression to that of untransformed CREF cells. However, Ha-ras/Krev-1-coexpressing CREF cells retain, albeit with extended latency periods, both tumorigenic and metastatic potential that is not related directly to the final level of Ha-ras or Krev-1 mRNA or the Ha-ras p21 transforming protein. Development of metastatic potential is, however, directly correlated with a reduction in nm23-H1 and TIMP-1 transcription and mRNA levels and an enhanced expression of cripto, 94-kDa GEL, osteopontin and transin. In contrast, expression of additional tumor-suppressor genes, such as the RB gene and p53, or genes associated with tumorigenesis in other model systems, such as major excreted glycoprotein (MEP), 72-kDa gelatinase/type IV collagenase (72-kDa GEL), fibronectin (FIB), tenascin and intracellular adhesion molecule 1 (ICAM-1) is not altered in a consistent manner during in vitro transformation suppression or escape from tumorigenic and metastatic suppression. These results indicate that Krev-1 suppression of the Ha-ras-transformed/oncogenic phenotype is associated with a distinct program of gene expression changes manifested by altered rates of transcription and steady-state mRNA levels of specific oncogenic-suppressing and oncogenic-inducing genes. These data support a model of Ha-ras-induced metastasis in CREF cells that involves a direct modulation in the expression/suppression of specific combinations of oncogenic-suppressor genes and metastasis-promoting genes that are regulated coordinately in the process of tumor progression.
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PMID:Defining the critical gene expression changes associated with expression and suppression of the tumorigenic and metastatic phenotype in Ha-ras-transformed cloned rat embryo fibroblast cells. 847 44

Homeobox-containing genes comprise a gene family coding for transcription factors involved in normal development. Class I human homeobox (HOX) genes display a peculiar chromosomal organization, perhaps directly related to their function. Aberrant expression of homeobox genes has been associated with both morphological abnormalities and oncogenesis. We have reported that HOX gene expression is (i) specific for normal adult human organs (kidney, colon, lung) and (ii) altered in cancer specimens according to their histological type and stage of tumor progression. Here, we have investigated whether patterns of HOX gene expression are associated with tumor heterogeneity by analyzing the expression of the entire panel of 38 HOX genes in clones isolated from a single human metastatic melanoma call line (Me 665/2). The differential expression of a block of genes located at the 5' end of the HOX C locus allows melanoma clones to be classified into 2 major groups. The 2 patterns of HOX gene expression are inversely associated with 2 distinct surface phenotypes for integrins (VLA-2, VLA-5 and VLA-6) and the adhesion molecule ICAM-1. The genes of the HOX C locus are silent in the clones with high levels of integrins VLA-2, VLA-5 and VLA-6 and of the adhesion molecule ICAM-1 but actively expressed in the clones with low levels of ICAM-1 and lacking VLA-2, VLA-5 and VLA-6. Our results indicate that HOX gene expression reflects the intra-tumor heterogeneity of melanoma clones and suggest that the expression of surface molecules involved in cell-cell and cell-matrix interactions may be related to the patterns of HOX gene expression.
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PMID:Differential patterns of HOX gene expression are associated with specific integrin and ICAM profiles in clonal populations isolated from a single human melanoma metastasis. 864 34


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