Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0035412 (rhabdomyosarcoma)
 6,156 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cell surface receptors for echovirus, a common human pathogen, were identified with monoclonal antibodies that protected susceptible cells from infection with echovirus 1. These monoclonal antibodies, which prevented virus attachment to specific receptor sites, recognized the alpha and beta subunits of the integrin VLA-2 (alpha 2 beta 1), a receptor for collagen and laminin. RD rhabdomyosarcoma cells expressed little VLA-2, did not bind to 35S-labeled virus, and resisted infection until transfected with complementary DNA encoding the alpha 2 subunit of VLA-2. Thus, integrins, adhesion receptors important in interactions between cells and with the extracellular matrix, can mediate virus attachment and infection.
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PMID:Identification of the integrin VLA-2 as a receptor for echovirus 1. 155 54

Cloned integrin alpha 2 subunit complementary DNA was expressed on human rhabdomyosarcoma (RD) cells to give a functional VLA-2 (alpha 2 beta 1) adhesion receptor. The VLA-2-positive RDA2 cells not only showed increased adhesion to collagen and laminin in vitro, but also formed substantially more metastatic tumor colonies in nude mice after either intravenous or subcutaneous injection. These results show that a specific adhesion receptor (VLA-2) can markedly enhance both experimental and spontaneous metastasis. In contrast to the metastasis results, there was no difference in either the in vitro growth rate or apparent in vivo tumorigenicity of RD and RDA2 cells.
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PMID:In vitro and in vivo consequences of VLA-2 expression on rhabdomyosarcoma cells. 201 40

Integrin plays an important role in tumor metastasis through its interaction with extracellular matrix and endothelial cell. We have examined the role of each integrin in tumor metastasis by using transfection of integrin cDNA into various cells. Transfection of integrin alpha 2 subunit into RD cells, human rhabdomyosarcoma cells which do not express integrin alpha 2 beta 1, potentiated the frequency of metastases in various organs; lung, bone, adrenal gland, lymph node. alpha 4-transfectant of Chinese hamster ovary (CHO) cells, which do not have alpha 4 beta 1 on the cell surface, metastasized to bone through its interaction with VCAM-1 in the bone marrow stroma cells. On the other hand, alpha 5-transfectant of CHO cells was much less tumorgenic than parent CHO cells. These data suggest integrin influence tumor metastasis sometimes favorably and sometimes unfavorably according to the activity and the balance of various integrins.
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PMID:[Analysis of the mechanism of tumor metastasis by the transfection of integrin cDNA]. 763 1

To assess directly the functional role of the integrin VLA-3 (alpha 3 beta 1), we transfected human alpha 3 cDNA into erythroleukemia (K562) cells and rhabdomyosarcoma (RD) cells. The resulting transfectants (KA3 and RA3) expressed alpha 3 beta 1 on the cell surface as confirmed using a panel of nine anti-alpha 3 monoclonal antibodies. Neither of the transfected cells exhibited increased adhesion to the extracellular matrix proteins fibronectin, laminin, and collagen. However, the KA3 transfectants did bind strongly to the extracellular matrix deposited by epidermal and carcinoma cell lines, allowing the cells to attach and spread. Binding to this cell-deposited ligand, probably containing epiligrin/kalinin, was specific to VLA-3 and could be inhibited by anti-alpha 3 antibodies and by EDTA, but not by RGD peptides. In marked contrast to other integrins (VLA-2 and VLA-4), VLA-3 showed high constitutive activity in K562 cells, but was minimally active in RD cells. Also contrasting with other beta 1 integrins, VLA-3 was minimally stimulated by the anti-beta 1 monoclonal antibody TS/216 under normal conditions. VLA-3-mediated adhesive function was well supported by either Mg2+ or Mn2+, but was almost completely abolished by the presence of 1 mM Ca2+. Surprisingly, this negative Ca2+ effect was completely overcome by the addition of the stimulatory anti-beta 1 monoclonal antibody TS2/16. Together, these results point to markedly distinct regulation for VLA-3 function compared to other beta 1 integrins. Also, all anti-VLA-3 antibodies were able to induce temperature-dependent homotypic cell aggregation of KA3 cells, but not K562 cells. However, this aggregation did not appear to be directly mediated by VLA-3 since it was not inhibited by EDTA. In addition, no enhancement of heterotypic cell-cell adhesion was observed in alpha 3-transfected cells.
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PMID:The function and distinctive regulation of the integrin VLA-3 in cell adhesion, spreading, and homotypic cell aggregation. 847 8

Various beta 1 integrins (VLA-2, VLA-3, VLA-4) have been suggested to bind directly to themselves or to each other, thus mediating cell-cell adhesion. Here we expressed the human alpha 2 and alpha 3 subunits in three different cell lines (human erythroleukemia K562, human rhabdomyosarcoma RD and Chinese hamster ovary CHO cells). Although cell surface alpha 2 beta 1 and alpha 3 beta 1 in the transfectants mediated adhesion to matrix ligands (collagen or laminin 5, respectively), in no case did we observe enhanced cell-cell adhesion. In the presence of a range of different divalent cation concentrations, stimulatory anti-beta 1 antibodies or anti-alpha 3 antibodies, VLA-2 and VLA-3 still did not appear to interact directly, through either heterophilic (i.e. VLA-3/VLA-2) or homophilic (i.e. VLA-3/VLA-3) mechanisms, to mediate cell-cell adhesion. Furthermore, in some but not all alpha 3 transfectants we observed an unexpected decrease in cell-cell adhesion, suggesting a novel anti-adhesive function. This inhibitory effect was not observed for alpha 2 transfection nor when the alpha 3 cytoplasmic tail was exchanged with that of another integrin alpha subunit. Finally, no evidence for VLA-4/VLA-4 mediated cell-cell adhesion was observed using alpha 4-transfected K562 and CHO cells. In conclusion, using many different combinations of cell lines, we found that cell-cell adhesion mediated by direct integrin/integrin interaction is not a widespread phenomenon, and is not observable in standard cell-cell adhesion assays. Furthermore, in some cell combinations, alpha 3 expression may actually cause diminished cell-cell adhesion.
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PMID:Investigation of the role of beta 1 integrins in cell-cell adhesion. 858 74

It is now known that members of the selectin and integrin families are critical in the initial interaction of cells in circulation with endothelial surfaces. Also, platelet/endothelial cell adhesion molecule-1 has been shown to be involved in transendothelial migration of extravasating cells. Little is known about adhesion molecules involved in subsequent postextravasation events. In this study, the significance of VLA-2 (alpha2beta1) integrin in the movement of human rhabdomyosarcoma RD cells in the liver was characterized by in vivo videomicroscopy. Results show that after extravasation, the mock-transfected RDpF cells were able to migrate to the subcapsular region of the liver. Although the RDX2C2 transfectant expressing VLA-2 integrin extravasated equally well, a majority of RDX2C2 cells remained in close proximity to blood vessels and failed to reach the subcapsular region. The functional involvement of VLA-2 in affecting the ability of RD cells to reach the subcapsular region was verified by the preparation of an RD transfectant [RDX2C2(I-)] expressing a nonfunctional variant of VLA-2 lacking the inserted (I)-domain of alpha2 subunit. In vivo microscopy showed that RDX2C2(I-) cells migrated in a manner similar to control RDpF cells. To demonstrate that RDX2C2 cells that remained in dose proximity to blood vessels were due to VLA-2 function, a blocking monoclonal antibody against VLA-2 (BHA2.1) was prepared. Mice were injected with BHA2.1 or control monoclonal antibody P3 at the time when RDX2C2 cells completed their extravasation. Treatment with BHA2.1 increased the number of RDX2C2 cells that reached the subcapsular region and subsequently formed tumor foci. Therefore, VLA-2 integrin expression has major roles in postextravasation movement and affects tumor foci formation at the liver surface.
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PMID:Integrin VLA-2 (alpha2beta1) function in postextravasation movement of human rhabdomyosarcoma RD cells in the liver. 867 74

Integrins are the major family of cell surface receptors that mediate adhesion to the extracellular matrix and sometimes cell-cell adhesive interactions. These integrin-mediated adhesive interactions are involved in the regulation of many cellular functions, including embryonic development, tumor cell growth and metastasis, programmed cell death, hemostasis, inflammation, immune reaction, bone reabsorption, etc. Integrins are composed of alpha and beta transmembrane subunits selected from among 16 alpha and 8 beta subunits that heterodimerize to produce more than 20 different receptors which bind specific ligands. Integrins link to intracellular cytoskeletal complexes and bundles of actin filaments. There have been many reports about intracellular signaling pathways activated by integrin-ligand interactions. Integrin may play an important role in tumor metastasis through its interaction with extracellular matrix and endothelial cell. We have examined the role of each integrin in tumor metastasis by using transfection of integrin cDNA into various cells. Transfection of integrin alpha 2 subunit into RD cells, human rhabdomyosarcoma cells which do not express integrin alpha 2 beta 1, potentiated the frequency of metastases in various organs; lung, bone, adrenal gland, lymphnode. alpha 4-transfectant of Chinese hamster ovary (CHO) cells, which do not have alpha 4 beta 1 on the cell surface, metastasized to bone through its interaction with VCAM-1 in the bone marrow stroma cells. On the other hand, alpha 5-transfectant of CHO cells was much less tumorigenic than parent CHO cells. These data suggest integrin influence tumor metastasis sometimes favorably and sometimes unfavorably according to the activity and the balance of various integrins.
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PMID:[Adhesion molecules and cancer metastasis]. 930 10