Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0677930 (primary tumor)
 20,210 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Metastases result from the implantation of tumor cells into various organs, distant from the primary tumor. Among primary tumor cells, a small number undergo genetic events determining metastatic function acquisition. The metastatic function comprises the lack of homotypic intercellular connections, due to proteolytic enzyme effects and/or lack of adhesion molecule synthesis, stimulation of peri- and intratumoral angiogenesis, motility adhesion molecule synthesis, stimulation of peri- and intratumoral angiogenesis, motility and invasiveness, adhesiveness to acellular substrates or heterotypic cells, resistance to immune defenses, alteration of growth factor receptivity, and even growth autonomy. Formation of metastatic foci needs the establishment of an ecosystem born from the contribution of both host and tumor and in which respective cells interact.
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PMID:[Cancer metastasis]. 754 47

It is now clear that adhesive interactions play a critical role in the process of metastatic tumor dissemination. Adhesion molecules act as both positive and negative modulators of the metastatic process. Molecules such as E-cadherin that promote homotypic tumor cell adhesion function to maintain intercellular contacts that confine cells to the primary tumor site and are negatively correlated with metastatic potential. Because tumor cells are rapidly eliminated from the circulation, those cells that can quickly arrest in the vasculature at a secondary site and pass through the vessel wall into the surrounding tissue will have a selective advantage toward establishing new metastatic colonies. The first step in this process is specific adhesion to venular endothelial cells in selected organs, a process mediated by tumor cell surface molecules such as Sialyl LewisX or the VLA-4 (alpha 4 beta 1) integrin that mediate binding to endothelial adhesion molecules such as the E-selectin or the vascular cell adhesion molecule, VCAM-1. Site-specific endothelial determinants such as the lung endothelial cell adhesion molecule, LuECAM, may additionally specify particular sites for preferential adhesion and subsequent site-specific metastasis of particular tumor types. After adherence to endothelial cells and subsequent endothelial retraction, metastatic tumor cells must adhere to elements of the subendothelial basement membrane such as laminin and types IV and V collagen, interactions frequently mediated by members of the beta 1 and beta 4 integrin families. Finally, metastatic tumor cell adhesion to connective tissue elements such as fibronectin, type I collagen and hyaluronan, mediated by molecules such as the beta 1 integrins and by the CD44 cell surface adhesion molecule, are required for movement of tumor cells into the subendothelial stroma and subsequent growth at these new sites. Thus, metastatic potential can be influenced both positively and negatively by a variety of cell surface adhesive molecules that act both independently and in concert to direct tumor cells to particular tissues, allowing them to arrest in those tissues, migrate across the vessel wall and grow at the secondary site. In the current review, I discuss the nature of the adhesion molecules that have been implicated in the metastatic process, emphasizing those molecules that have been shown to correlate with metastasis in clinical human tumors or that have been shown to influence metastatic potential in in vivo experimental assays.
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PMID:Adhesion molecules in tumor metastasis. 840 Jan 43

Recent molecular biology investigations have demonstrated that tumor progression and dissemination in bladder cancer is a highly complicated phenomenon, consisting of multiple distinct steps and regulated by a great number of different genes. Some of these genes involved in the specific steps of tumor progression and dissemination have been identified. Several oncogenes, e.g., the epithelial growth factor receptor (EGF-R), and tumor-suppressor genes, e.g., the p53 gene, have been found to correlate significantly with tumor progression. The decreased expression of cell-adhesion molecules such as E-cadherin appears to facilitate tumor-cell detachment in the primary tumor, whereas expression of the intercellular adhesion molecule (ICAM)-1 might be of relevance for cell attachment at the metastatic site. Tumor invasion through the basement membrane has been correlated with a decreased expression of laminin and elevated urinary levels of acidic fibroblast growth factor. Although the complex processes related to dissemination are far from being completely understood, the finding of differential expression of distinct genes appears to provide the first targets for therapeutic intervention.
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PMID:Molecular biology of dissemination in bladder cancer--laboratory findings and clinical significance. 880 98

The adhesive interaction between tumor cells and host cells or the extracellular matrix plays a crucial role in metastasis formation. Therefore, understanding the mechanism controlling metastasis may assist in the development of antimetastatic therapy. We have used synthetic or recombinant polypeptide analogues containing the Arg-Gly-Asp (RGD) sequence found in the functional domains of fibronectin, such as poly(RGD) or CH-271, to regulate the mechanisms involved in cell adhesion during the metastatic process. Poly(RGD) inhibited experimental lung and liver metastasis effectively when coinjected i.v. with various types of tumors. In a model of spontaneous lung metastasis using the B16-BL6 melanoma, repeated administration of this polypeptide before or after surgical excision of the primary tumor resulted in a significant inhibition of tumor metastasis without affecting the growth of the primary tumor and substantially prolonged the survival time of mice. The mechanism responsible for the inhibition of tumor metastasis by the polypeptides is at least partly associated with the ability to interfere with cellular functions such as adhesiveness, motility and invasiveness in the process of metastasis. Combined treatment of the CH-271 fusion polypeptide and anticancer drugs, i.e., anti-adhesion therapy combined with chemotherapy, caused a marked inhibition of lung and liver metastasis of tumors as compared with either treatment alone or with the control. In contrast, the promotion of tumor cell interaction with immune cells via cell adhesion molecules, which differs from the anti-adhesive mechanism, may lead to the induction of anti-tumor immune responses and, consequently, to the inhibition of tumor metastasis. The transfection of the gene of the B7-1 adhesion molecule into tumor cells (B16-BL6 or K1735-M2 melanoma) resulted in the remarkable reduction of lung metastasis caused by the i.v. injection into mice. Immunization of B7-transfected tumor was effective as a tumor vaccine for preventing the metastasis of B7 negative original tumor cells. Thus, the regulation of the adhesive interaction with tumor cells may provide a new and promising approach for the control and prevention of cancer metastasis.
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PMID:Cell adhesion molecules and cancer metastasis. 943 54

One of the principle targets for metastasis of follicular thyroid carcinoma (FTC) is the skeleton. Because no data are available on the role of the integrin adhesion molecule family in the attachment of FTC to bone, we studied the attachment characteristics of three FTC cell lines to bone and the role of integrins. Three cell lines were used from the same patient, one (FTC-133) from the primary tumor and two (FTC-236 and FTC-238) from metastases. Attachment of FTC cell lines to bone was assessed on conditioned medium of an osteoblastic cell line, coated onto plastic, as an in vitro model of bone matrix. The synthetic RGD (Arg-Gly-Asp) peptide GRGDS impaired attachment of the FTC cell lines to bone matrix, demonstrating the role of integrins in the attachment of FTC to bone. Attachment of FTC-133 to bone matrix was blocked completely by GRGDS, whereas attachment of FTC-236 and FTC-238 could not be impaired completely. Semiquantitative polymerase chain reaction (PCR) of cDNA from the cell lines indicated stronger expression of alpha5 integrin mRNA in FTC-133 than in the other cell lines. In line with this, attachment of FTC-133 to bone matrix could be inhibited almost completely by anti alpha5 and beta1 integrin antibodies, indicating the importance of the fibronectin receptor in the attachment of FTC-133 to bone. Binding of FTC-236 and FTC-238 to bone matrix could not be inhibited completely by anti-integrin antibodies, suggesting an additional role of nonintegrin adhesion molecules in the attachment of FTC-236 and FTC-238 to bone. The synthetic bone sialoprotein cyclic peptide, CNB, revealed antiadhesive effects in the binding of FTC to bone. In conclusion, integrins play an important role in the attachment of metastatic FTC to bone. Differences in the functional involvement of integrins in the attachment to bone are observed between the three cell lines studied. From the present results, antiadhesive interventions with synthetic RGD peptides in FTC may be designed.
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PMID:Role of integrins in the attachment of metastatic follicular thyroid carcinoma cell lines to bone. 949 50

Angiogenesis has an important role in the progression of solid tumors. Therefore, we measured the blood levels (ELISA) of angiogenic factors [basic fibroblast growth factor (bFGF), hepatocyte growth factor/scatter factor, and vascular endothelial growth factor (VEGF)] and soluble adhesion molecules [E-selectin, intercellular adhesion molecule (ICAM-1), platelet endothelial cell adhesion molecule-1, and vascular cell adhesion molecule-1] in 76 consecutive patients with untreated renal cell carcinoma and 41 healthy controls to evaluate their prognostic value. The serum levels of bFGF, hepatocyte growth factor, and VEGF were significantly higher in patients with renal cancer than they were in healthy subjects. bFGF and VEGF values were significantly higher in patients with disseminated cancer (N+ and/or M+) than they were in those with undisseminated (M-N-) cancer: median = 27 pg/ml, range = 5-118, n = 15 versus median = 8 pg/ml, range = 1-149, n = 61 (P = 10(-4)) for bFGF; and median = 883 pg/ml, range = 200-2317, n = 15 versus median = 278 pg/ml, range = 0-1704, n = 61 (P = 0.006) for VEGF. The blood levels of ICAM-1 and vascular cell adhesion molecule-1 were significantly higher, and the levels of E-selectin and platelet endothelial cell adhesion molecule-1 were significantly lower in patients with renal cancer than they were in controls. Plasma ICAM-1 was higher in metastatic patients (M+) than they were in nonmetastatic (M-) patients: median = 687 ng/ml, range = 294-1091, n = 12 versus median = 408 ng/ml, range = 217-1375, n = 64 (P = 10(-4)). ICAM-1 and bFGF blood values were correlated with the size of the primary tumor. The interleukin 6 and tumor necrosis factor-alpha (TNF-alpha) values of these patients have been previously published and are included in the survival analysis. Univariate analysis showed that bFGF, ICAM-1, interleukin 6, and TNF-alpha, before treatment, were prognostic factors. In multivariate analysis for proportional hazard regression, only TNF-alpha was an independent prognostic indicator, with a normal plasma TNF-alpha being highly predictive for a good prognosis in patients with untreated renal cell carcinoma.
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PMID:Are angiogenic factors, cytokines, and soluble adhesion molecules prognostic factors in patients with renal cell carcinoma? 981 46

Although intradermal primary tumor growth and spontaneous liver metastasis of ESbL-lacZ lymphoma in syngeneic DBA/2 mice are progressive and malignant, they are characterized by a transient plateau period with a constant tumor diameter and a low number of metastasized cells in the liver. This period, which was shown to be immune dependent, was followed by a second expansion phase characterized by a preferential localization of tumor cells in the periportal areas of liver lobules (mosaic phenotype). To elucidate possible mechanisms leading to the plateau period as well as for the mosaic-like metastasis pattern, we investigated, using flow cytometry analysis, alterations in costimulatory and adhesion molecule expression in liver sinusoidal cells as well as in tumor cells isolated directly ex vivo throughout the kinetics of metastasis. In tumor and sinusoidal cells, we found up-regulation in the expression of MHC class II and B7 molecules during the plateau period. These molecules, which facilitate cell-mediated immune responses, were again down-regulated during the final exponential tumor growth and metastasis. In the final expansion phase, in which the mosaic phenotype of liver metastasis is seen, we detected a significant increase of leukocyte function-associated antigen-1/intercellular adhesion molecule-1 expression in both tumor and sinusoidal cells, suggesting tumor cell-sinusoidal cell interactions. vascular cell adhesion molecule-1/very late activated antigen-4 did not show any modification during the whole metastatic process. In vivo application of monoclonal antibodies directed to leukocyte function-associated antigen-1 and intercellular adhesion molecule-1 appeared to block the spread of metastasis, while no effect was seen with monoclonal antibodies directed to vascular cell adhesion molecule-1 and very late activated antigen-4. This study reveals in situ expression changes of cell surface molecules in tumor and host cells during metastasis. The changes seen during the plateau phase and during the second expansion phase differ, suggesting associations with mechanisms of immune control and tumor immune evasion, respectively.
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PMID:Dynamic expression changes in vivo of adhesion and costimulatory molecules determine load and pattern of lymphoma liver metastasis. 981 35

The outcome of breast carcinoma is usually determined by multiple factors. Aberrant expression of the cell adhesion molecule CD 44 has been claimed to be associated with poor prognosis in various human malignancies. This study was designed to investigate any correlation between the soluble adhesion molecule CD 44 and the clinicopathologic variables and to evaluate the possible prognostic significance of soluble CD 44. Venous blood samples were preoperatively collected from 100 patients with invasive breast carcinoma. The serum levels of different soluble CD 44 molecules (CD 44 standard form and CD 44 splice variant V6) were measured with an enzyme immunoassay method. The data of primary tumor status, age, estrogen receptor status, lymph node status, histologic grading, distant metastases status, TNM staging, S-phase fraction, and ploidy pattern were collected and evaluated simultaneously with the serum levels of soluble CD 44 st and CD 44 V6. Twenty healthy subjects were used as the control group. The serum levels of soluble CD 44 st showed no significant elevation in patient group. The mean value of soluble CD 44 V6 in patient group was 269.2 +/- 94.3 ng/ml and that of the control group was 179.5 +/- 50.7 ng/ml; the difference was significant (p < 0.01). In multivariate analysis, distant metastasis (p < 0.05) and TNM staging (p < 0.01) appeared as independent factors regarding the significant higher serum levels of soluble CD 44 V6. Based on our preliminary results, preoperative serum soluble CD 44 V6 is closely related to distant metastases and TNM staging. The possible role of soluble CD 44 V6 in the prognostic value of breast carcinoma deserves further elucidation and evaluation with long-term patient follow-up.
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PMID:Evaluation of the prognostic value of serum soluble CD 44 in patients with breast cancer. 1059 65

Changes in the expression of integrins and cadherins might contribute to the progression, invasion and metastasis of transitional cell cancer of the bladder and of melanomas. The expression of alpha5 (P < 0.001), alpha2 and beta1 (P < 0.05 - P < 0.001) integrin subunits in melanoma cells from noncutaneous metastatic sites (WM9, A375) were significantly increased as compared to cutaneous primary tumor (WM35) and metastatic (WM239) cell lines. These differences might be ascribed to the invasive character of melanoma cells and their metastasis to the noncutaneous locations. The significantly heterogeneous expression of beta1 integrin subunit in two malignant bladder cancer cell lines (T24 and Hu456) and nonsignificant differences in the expression of alpha2, alpha3, and alpha5 subunits between malignant and non-malignant human bladder cell lines do not allow an unanimous conclusion on the role of these intergrin subunits in the progression of transitional cancer of bladder. The adhesion molecule, expressed in all studied melanoma and bladder cell lines, that reacted with anti-Pan cadherin monoclonal antibodies was identified as N-cadherin except in the HCV29 non-malignant ureter cell line. However, neither this nor any other bladder or melanoma cell line expressed E-cadherin. The obtained results imply that the replacement of E-cadherin by N-cadherin accompanied by a simultaneous increase in expression of alpha2, alpha3 and alpha5 integrin subunits clearly indicates an increase of invasiveness of melanoma and, to a lesser extent, of transitional cell cancer of bladder. High expression of N-cadherin and alpha5 integrin subunit seems to be associated with the most invasive melanoma phenotype.
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PMID:Expression of beta1-integrins and N-cadherin in bladder cancer and melanoma cell lines. 1199 5

The immunocytochemical detection of isolated disseminated tumor cells (ITC) in the bone marrow of breast cancer patients, what is called minimal residual disease (MRD), has been demonstrated to be of prognostic value in all stages of the disease. In order to definitely prove the origin of these cells from the primary tumor it is necessary to identify common factors on both tumor tissue and ITC, furthermore a more detailed characterization could help to improve their prognostic impact by defining certain subgroups and possibly establish new therapeutic strategies. We examined the expression/amplification of HER2neu, CD 44 adhesion molecule and CD 31 angiogenetic factor on more than 200 primary tumor tissues by immunohistochemistry or fluorescence in situ hybridisation, resp., and found no sign. correlation with the detection of ITC. After a median follow-up of 32 months only ITC in the bone marrow were of prognostic significance. In a small number of patients we examined the expression of topoisomerase II alpha, a key enzyme of DNA replication, and its predictive value of eliminating ITC by anthracyclin based chemotherapy. No correlation with the presence of ITC before or after chemotherapy could be found, yet pat. with topoisomerase II alpha neg. tumors showed a trend to reduced disease free survival. Because of the very low number of ITC per bone marrow sample, the direct characterization of these factors on ITC stays difficult without the possibility of tumor cell enrichment or cell culture. Preliminary results on multi colour stained samples indicate that a selection of certain biological factors takes place during tumor cell dissemination.
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PMID:[Tumor biology of primary breast cancer and minimal residual disease]. 1250 57


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