Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The process of metastasis involves a series of sequential steps in which malignant cells are released from the primary tumor and metastasize to distant sites. Syndecan-1 is a cell surface proteoglycan that mediates cell adhesion and undergoes changes upon cell transformation of some cells that may contribute to the process of metastasis. To investigate the possible role of syndecan-1 in cell proliferation and metastatic potential, we employed a highly metastatic cell line (KLN 205) derived from mouse lung squamous cell carcinoma that expressed moderate amounts of syndecan-1. At first, endogenous syndecan-1 production was inhibited by an antisense oligodeoxynucleotides (ODNs). Since antisense ODNs of syndecan-1 inhibited cell growth, we established stable transfectants of syndecan-1 in this cell line to examine a proliferative advantage with the level of syndecan-1 expression. Overexpresser cells grew at a significantly faster rate than the vector-transfected control and showed greater incidence of tumor formation when injected subcutaneously into nude mice. Surprisingly, overexpresser cells enhanced pulmonary metastasis when injected intravenously. These results indicate that syndecan-1 expression plays a role in the control of cell proliferation and suggest that syndecan-1 expression may be involved in facilitating distant metastasis of tumor cells once they managed to enter the bloodstream (after intravasation steps).
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PMID:Altered proliferative and metastatic potential associated with increased expression of syndecan-1. 981 73

The distributions of hyaluronan (HA) and its CD44 receptor were studied in 24 normal, 27 dysplastic samples of laryngeal epithelium and in 172 squamous cell carcinomas (LSCC), using a specific probe prepared from cartilage proteoglycan (bHABC, biotinylated hyaluronan binding complex) and a monoclonal antibody (Hermes 3). HA and CD44 were expressed similarly in all normal and about 90% of dysplastic and neoplastic laryngeal epithelia. In the normal epithelium HA and CD44 were homogeneously distributed throughout the epithelium, whereas the most superficial layers were negative. This was in contrast to the picture in dysplastic epithelium and well-differentiated invasive carcinomas, which were entirely HA and CD44 positive. Local areas with a low signal for HA and CD44 were present in 11% and 22% of the samples with dysplasia, and in 27% and 28% of those with carcinoma, respectively. The presence of this staining irregularity was associated with poor differentiation of the carcinoma, a significantly elevated mitotic index and a high frequency of nodal spreading and metastases. Furthermore, the irregular staining showed a trend towards poor disease-free survival, suggesting that an altered metabolism of HA is a common feature in LSCC and is associated with an aggressive growth pattern.
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PMID:Irregular expression of hyaluronan and its CD44 receptor is associated with metastatic phenotype in laryngeal squamous cell carcinoma. 1007 Dec 33

Metastasis is a sequence of events including proliferation, migration, adhesion, invasion and subsequent metastatic growth of tumour cells in distant organs. We previously showed that highly metastatic variants of murine melanoma cells express higher levels of the basement membrane proteoglycan perlecan than low or non metastatic variants and expression of an antisense perlecan can reduce metastatic potential. In contrast, antisense expression of perlecan in fibrosarcoma cells was reported to enhance tumorigenesis. To better understand the role of perlecan in angiogenesis we have transfected KS-IMM, an immortalized cell line derived from a human Kaposi s sarcoma, with an antisense perlecan construct and investigated the positive/negative role of perlecan in KS. KS-IMM cells were transfected with either empty vector (neo) or the antisense perlecan construct and clones were isolated. Immuno-blot analysis showed a reduction of perlecan levels in two (AP3 and AP4) isolated clones, in Northern blot analysis endogenous perlecan was undetectable in the AP3 and AP4 clones, while it was present in the neo control clones. AP clones had a reduced migration to HGF in Boyden chambers as compared to neo clones. Proliferation in low serum or serum-free conditions was strongly reduced in the AP clones as compared to the neo control cells. The neotransfected cells showed rapid proliferation in low serum supplemented with HGF and VEGF, while antisense transfected clones showed little response. Finally, AP-trasfected KS-IMM cells had significantly reduced migration to VEGF and HGF with respect to controls. In contrast, when the AP transfected cells were injected in nude mice they paradoxically showed enhanced tumor growth as compared to controls. Our preliminary data indicate that perlecan reduction plays a crucial role on Kaposi s sarcoma cell migration and proliferation in vitro. However, in vivo KS-IMM depleted of perlecan had a growth advantage. A possible hypothesis is that perlecan is necessary for growth of KS-IMM cells in vitro, however its down-regulation might promote angiogenesis through increased angiogenic growth factor diffusion, resulting in enhanced tumor growth in vivo.
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PMID:Phenotypic alterations in Kaposi's sarcoma cells by antisense reduction of perlecan. 1074 82

Osteosarcoma cells are useful for investigating bone metabolism as malignant counterpart of osteoblasts. In hematogenous metastases of osteosarcoma cells, the cells need to adjust to various changes in pericellular environment. The changes in pericellular environment may change intracellular environment and consequently the secretion of matrix metalloproteinases (MMPs) which destroy extracellular matrices. In this report, a new cell line, KOS-1, derived from human osteoblastic osteosarcoma was established, and we assumed various culture conditions containing ingredients of the extracellular matrix to make a comparative study on MMPs detected from the culture supernatants. A wide spectrum of MMPs, including MMP-1 and -3 which were increased in the presence of interleukin 1 beta, was detected in this cell line. Production of MMP-1, the enzyme which decomposes types I, II, III and X collagen, by the cells, was increased in the presence of type I collagen. MMP-3 (stromelysin-1) which degrades types III and IV collagen, laminin, fibronectin, proteoglycan, etc. was produced more abundantly in the presence of type IV collagen. MMP-2 (72-kd type IV collagenase/gelatinase A) activity was found to be increased in the presence of gelatin and type IV collagen. The MMPs production in cultured osteosarcoma cells was changed depending on the culture conditions. This indicates that the same osteosarocma cells produce different amounts and kinds of enzymes involved in local infiltration and remote metastases and increase the production of the enzymes most required under a specific environment.
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PMID:Establishment of an osteoblastic osteosarcoma cell line and effects of cell culture conditions on secretion of matrix metalloproteinases from the cultured osteosarcoma cells. 1094 49

Because heparan sulfate proteoglycans mediate cell adhesion and control the activities of numerous growth and motility factors, they play a critical role in regulating the metastatic behavior of tumor cells. Due to their utilitarian nature, heparan sulfate proteoglycans may at times act as inhibitors of cell invasion and at other times as promoters of cell invasion, with their function being determined by their location (cell surface or extracellular matrix), the heparin-binding molecules they associate with, the presence of modifying enzymes (proteases, heparanases) and the precise structural characteristics of the proteoglycan. Also, the tissue type and pathophysiological state of the tumor influence proteogylcan function. This review summarizes our current knowledge of the role heparan sulfate proteoglycans play in regulating tumor cell metastasis, proposes mechanisms of how these molecules function and examines the potential for discovery of new therapeutic approaches designed to block metastatic cancer.
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PMID:Heparan sulfate proteoglycans in invasion and metastasis. 1129 74

Motility factors, e.g. SF/HGF (scatter factor/hepatocyte growth factor) or AMF (autocrine motility factor) can influence the migration of tumor cells in vitro and may facilitate invasive growth and metastases in vivo. The production of motility factors was studied in cell lines derived from human cholangiocarcinomas. Culture supernatants from 5 different cholangiocarcinoma cell lines (EGI-1, RPMI 7451, MZ CHA-1, MZ CHA-2 and MZ CHA-3) were analyzed in scatter assays with NRK and MDCK cells as indicator cells which react with cellular migration in the presence of motility factors. Culture supernatants from 4 of the 5 cell lines investigated induced migration of the indicator cells thus demonstrating the production of motility factors. Three of the cell lines (MZ CHA-1, MZ CHA-2, RPMI 7451) produced a factor with a molecular weight ranging between 50 and 100 kDa, EGI-1 cells secreted a factor with a molecular weight >100 kDa. None of the factors was identical to HGF as demonstrated by the lacking reactivity in a HGF specific ELISA and by the inability to induce scattering of HPAF indicator cells like HGF. Similar to SF/HGF, the activity of the EGI-1 factor was inhibited by the proteoglycan heparin and stimulated the chemotactic cell migration, but in contrast to SF/HGF it could not induce invasive growth of NRK cells. The production of scatter factors could be involved in tumor progression and formation of metastases of cholangiocarcinomas.
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PMID:Motility factors identified in supernatants of human cholangiocarcinoma cell lines. 1129 63

Heparanase-1 (HPR1) is an endoglycosidase that specifically degrades the heparan sulfate chains of proteoglycan, a component of blood vessel walls and the extracellular matrix. Recent studies demonstrated that HPR1 expression is increased in a variety of malignancies and may play a critical role in tumor metastases. The HPR1 gene and its genomic structure have been recently cloned and characterized. To understand the mechanisms of HPR1 gene expression and regulation, we first mapped the transcription start site of the HPR1 gene and found that HPR1 mRNA was transcribed from the nucleotide position 101 bp upstream of the ATG codon. A 3.5-kb promoter region of the HPR1 gene was cloned. Sequence analysis revealed that the TATA-less, GC-rich promoter of the HPR1 gene belongs to the family of housekeeping genes. This 3.5-kb promoter region exhibited strong promoter activity in two thyroid tumor cell lines. Truncation analysis of the HPR1 promoter identified a minimal 0.3-kb region that had strong basal promoter activity. Truncation and mutational analysis of the HPR1 promoter revealed three Sp1 sites and four Ets-relevant elements (ERE) significantly contributing to basal HPR1 promoter activity. Binding to the Sp1 sites by Sp1 and to the ERE sites by GA-binding protein (GABP) was confirmed by electrophoretic mobility shift assay and competition and supershift electrophoretic mobility shift assays. Cotransfection of Sp- and GABP-deficient Drosophila SL-2 cells with the HPR1 promoter-driven luciferase construct plus the expression vector encoding the Sp1, Sp3, or GABP gene induced luciferase gene expression. Mutation or truncation of the Sp1 or ERE sites reduced luciferase expression in both SL-2 cells and thyroid tumor cell lines. Coexpression of GABPalpha/beta and Sp1 or Sp3 further increased luciferase reporter gene expression. Our results collectively suggest that Sp1 cooperates with GABP to regulate HPR1 promoter activity.
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PMID:Cloning and characterization of the human heparanase-1 (HPR1) gene promoter: role of GA-binding protein and Sp1 in regulating HPR1 basal promoter activity. 1177 47

Melanoma is among the few cancers with rising incidence. Currently there is no effective treatment for metastatic disease, but improved detection of melanoma has the potential to benefit the management of patients with early disease. Radioimmunodection by imaging with single-chain Fv (scFv) antibody fragments is one such emerging diagnostic method. However, the amount of scFv that can be produced at a scale suitable for use in patients is limiting. We have previously shown that the bacterial expression of a scFv derived from a monoclonal antibody (MAb) specific for melanoma-associated proteoglycan can be increased by light chain shuffling. In this report we show that a further increase in expression yield can be obtained by reversing the usual V(H)-V(L) orientation of scFvs to V(L)-V(H). Such seemingly minor changes have previously been reported to have unexpected effects on the in vitro and in vivo binding properties of recombinant antibodies. Our results show that reversal of the V domain orientation of the scFv improves expression by 150% without an adverse effect on melanoma binding in vitro and tumor targeting in vivo. Therefore, our results show that alteration of V domain orientation can improve the production yield of clinically useful antibody fragments. When used in combination with other antibody engineering approaches for increased antibody production changing the domain orientation is a simple strategy to achieve significant improvements in the production of scFvs for tumor radioimmunodetection for patient studies.
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PMID:Improved production by domain inversion of single-chain Fv antibody fragment against high molecular weight proteoglycan for the radioimmunotargeting of melanoma. 1183 53

The mechanisms underlying the inflammatory and metastatic processes share a number of similar pathways, such as those involving adhesion, migration and extravasation. In this article, the effects of pro-inflammatory cytokines on metastatic-related activities of colon cancer cells were tested. The expression and biological activity of the proteoglycan CD44 in low (LS174T) and high metastatic (HM7) cell lines following exposure to TNFalpha and IL-8 were assessed. Treated cells expressed more CD44 splice variants (CD44v), while CD44 standard protein (CD44s) expression remained unchanged. Treatment with TNFalpha induced IL-8 secretion and IL-8 gene transcription in a time-dependent manner. Both cytokines enhanced the ability of the cells to adhere to the CD44-specific ligand hyaluronic acid, an effect that was specifically blocked by an anti-IL-8 antibody. These results suggest that the effect of TNFalpha on IL-8 is responsible for the regulation of the expression of CD44 isoforms. Additional experiments showed that neither of the cytokines tested regulate the expression of CD44 gene regulation via activation of a well-characterized specific 22-bp epidermal growth factor regulatory element present in the CD44 promoter sequence, suggesting that this is not the mechanism of activation. We conclude that immuno-modulatory mediators can modify the expression of cell-to-cell or cell-to-matrix adhesion proteins, implicated in the determination of phenotypes associated with aggressiveness and metastasis of colon cancer cells.
Clin Exp Metastasis 2002
PMID:TNFalpha and IL-8 regulate the expression and function of CD44 variant proteins in human colon carcinoma cells. 1209 Apr 73

In view of the rising melanoma incidence and the absence of effective treatments for metastatic disease, there is an urgent need for new methods that allow the early detection of melanoma. To this end, in vivo detection by patient imaging with single-chain Fv (scFv) antibody fragments is an attractive diagnostic approach. However, high non-specific accumulation of scFvs in the kidney reduces image quality in this body area and prevents the use of scFvs for melanoma radioimmunotherapy. We have tested the effect of coadministration of L-lysine with (125)I-labelled scFvs against melanoma-associated proteoglycan on kidney accumulation in a nude mouse xenograft model. Coadministration of L-lysine had no significant effect on tumour accumulation of scFvs or blood clearance, but decreased kidney accumulation by factors of 2.25, 2.3, 6.3 and 5.8, respectively, at 1, 3, 6 and 18 h post-injection, and improved tumour to muscle contrast. The reduction in kidney accumulation was maximal at time points that can be extrapolated to patient studies. The time dependence of the effect suggests that further improvements could be achieved with an optimized dosing regimen. When combined with other strategies to reduce kidney accumulation of scFvs, coadministration of L-lysine has the potential to significantly improve tumour to kidney contrast.
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PMID:Reducing renal accumulation of single-chain Fv against melanoma-associated proteoglycan by coadministration of L-lysine. 1217 Jan 87


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