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Query: UMLS:C0677930 (
primary tumor
)
20,210
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
A recognized model of tumor invasion requires cells to adhere to epithelial basement membrane and extracellular matrix components triggering release of proteases thus allowing cancer cells to invade the substrate. This adhesion is mediated by beta 1 integrins, a family of receptors to substrates such as collagen, laminin, and
fibronectin
. In order to study tumor invasion in follicular thyroid cancer (FTC), we used cell lines derived from a single patient's FTC
primary tumor
(FTC-133), neck lymph node metastases (FTC-236), and lung metastases (FTC-238). In vitro invasion as determined by the ability of the tumor cells to penetrate Matrigel was assessed by scanning electron microscopy. FTC-133 did not invade, FTC-236 was moderately invasive, and FTC-238 was highly invasive. Immunoprecipation with a monoclonal antibody to beta 1 integrin subunits and SDS-PAGE showed increased synthesis and flow cytometry showed increased expression of this subunit in FTC-236 and FTC-238 compared to FTC-133. Proteolytic activity was assessed by gelatin zymography. FTC-238 cell extract and conditioned media exhibited a more complex array of proteases consistent with activated type I collagenase and stromelysin compared to the less invasive clones, however 72 and 92 kd gelatinases consistent with type IV collagenases were present in the conditioned media from all three lines. In conclusion, in vitro invasion parallels in vivo metastasis by the source cells in the FTC-133/236/238 cell-lines. The ability to invade basement membrane preparation correlates with increased synthesis and expression of beta 1 integrins and activation of tumor proteases.
...
PMID:Invasion by cultured human follicular thyroid cancer correlates with increased beta 1 integrins and production of proteases. 138 45
The possible mitogenic activity of
fibronectin
(FN) in human primary and metastatic melanoma lines and clones and the involvement of integrins in mediating this effect were evaluated. Quescent human melanoma cells cultured in serum-free medium proliferated in a dose- and time-dependent fashion to immobilized FN as indicated by [3H]thymidine incorporation, increment of cell number, and cell cycle analysis. This response to FN was observed with tumor clones isolated from a subcutaneous metastasis and with primary or metastatic melanomas from different patients, but only when tumor cells expressed the alpha 5 subunit of the FN receptor (i.e., VLA-5). Proliferation to FN by a
primary tumor
(Me4405) expressing all FN receptors and by a tumor clone (2/60) lacking only the alpha 4 subunit was inhibited by monoclonal antibodies to the alpha 5 and beta 1 but not by monoclonal antibodies to other subunits of FN receptors. Mapping of FN regions responsible for the proliferative signal was performed by stimulating melanoma cells with different FN proteolytic fragments and indicated that a significant mitogenic signal was provided by the M(r) 120,000 alpha-chymotrypsin fragment containing the Arg-Gly-Asp sequence. The proliferation of melanoma cells to FN and to FN fragments was also significantly inhibited by peptides containing the Arg-Gly-Asp sequence. These data indicate that FN can stimulate the proliferation of quiescent melanoma cells and that integrins as alpha 5 beta 1 are involved in the response of tumor cells to this extracellular matrix protein.
...
PMID:Role of the alpha 5 beta 1 integrin receptor in the proliferative response of quiescent human melanoma cells to fibronectin. 138 57
Cancer metastasis poses the greatest challenge to the eradication of malignancy. The majority of clinical and experimental evidence indicates that metastasis is a non-random, organ-specific process. Tumor cell interaction with endothelium and subendothelial matrix constitutes the most crucial factor in determining the organ preference of metastasis. A plethora of cell surface adhesion molecules, which encompass four major families (i.e., integrins, cadherins, immunoglobulins and selectins) and many other unclassified molecules, mediate tumor-host interactions. Adhesion molecules and adhesion processes are involved in most, if not all, of the intermediate steps of the metastatic cascade. Decreased E-cadherin expression and increased CD44 expression are clearly correlated with the acquisition of the invasive capacity of
primary tumor
cells. Similarly, altered expression pattern of many other adhesion molecules such as upregulated expression of the laminin receptors and depressed expression of
fibronectin
receptors (alpha 5 beta 1) appears to be involved in tumor cell invasion into the subendothelial matrix. Tumor cell-endothelium interactions involve several well-defined sequential steps that can be analyzed by the 'Docking and Locking' hypothesis at the molecular level. Tumor cell-matrix interactions are determined by the repertoire of adhesion receptors of tumor cells and the unique composition of organ-specific matrices. Our experimental data, together with others', suggest that the integrin alpha IIb beta 3 is one of the major players in these tumor-host interactions. Tumor-host interaction is a dynamic process which is constantly modulated by a host of factors including various cytokines, growth factors and arachidonate metabolites such as 12(S)-HETE. Delineation of the molecular mechanisms of tumor-host interactions may provide additional means to intervene in the metastatic process.
...
PMID:Adhesion molecules and tumor cell interaction with endothelium and subendothelial matrix. 142 22
We have investigated the anti-angiogenic effect of a polymeric peptide based on the Arg-Gly-Asp (RGD) core sequence of
fibronectin
as a monomer unit, i.e., poly(RGD), in syngeneic mice and in vitro. Single intratumoral administration of poly(RGD) on day 0, 1 or 7 after tumor implantation achieved a significant reduction of B16-BL6 melanoma colonization in the lungs, but did not affect the size of the
primary tumor
at the time of amputation. The number of capillary blood vessels oriented toward the tumor mass increased during the early growth phase after the intradermal inoculation of the tumor. Poly(RGD) significantly inhibited the formation of tumor neovascularization when co-injected with the tumor cells or separately injected intratumorally or intravenously on day 1 or 3 after tumor inoculation. This inhibitory effect of poly(RGD) was dose-dependent. Poly(RGD) was able to inhibit the haptotactic migration of endothelial cells along a gradient of substratum-immobilized
fibronectin
but not laminin. Tumor-conditioned medium (CM) by itself did not act as a chemoattractant when it was added in the lower compartment of a Transwell chamber, but promoted the endothelial cell migration to immobilized
fibronectin
or laminin. Poly(RGD) inhibited the enhanced cell migration to
fibronectin
but not to laminin in response to CM. Thus, poly(RGD)-mediated inhibition of tumor metastasis may be partly due to the inhibition of tumor-induced angiogenesis at primary and secondary sites.
...
PMID:Inhibition of tumor angiogenesis by a synthetic cell-adhesive polypeptide containing the Arg-Gly-Asp (RGD) sequence of fibronectin, poly(RGD). 169 94
Antigen expression in a human glioblastoma was investigated by immunochemical methods in the
primary tumor
, the first and second recurrence, a permanent cell line derived from the first recurrence and in its xenotransplantation tumors. In the
primary tumor
, GFAP, vimentin, S100, Leu-7 and glioma-associated antigens (GAA) as defined by the monoclonal antibodies (mAbs) MUC 2-39, MUC 8-22 and MUC 2-63 were markedly expressed. In the recurrences, gradual loss of GFAP and Leu-7 could be observed, whereas S100, vimentin and GAA gave similar results to those in the
primary tumor
. In contrast,
fibronectin
and collagen IV, which were restricted to the vessel walls in the
primary tumor
, were represented in sarcomatous areas of the recurrences. In some of these areas, co-expression of glial cell markers was observed. In short-term cell cultures, expression of glia- and glioma-associated antigens as well as
fibronectin
and collagen IV was comparable to that of the recurrent tumor tissue. In long-term passages, immunoreactivity of GFAP, Leu-7 and S100 decreased, whereas GAA, vimentin and
fibronectin
increased. Collagen IV positive cells were not visible beyond passage 15. Transplantation tumors were only partly positive for glial cell markers, but revealed strong immunoreactivity for GAA,
fibronectin
and collagen IV. With these observations we confirm that the phenotypic variability of glioma cells makes it difficult to identify the origin of cells in human glioblastomas from their antigenicity.
...
PMID:Antigen variation in a human glioblastoma: from the primary tumor to the second recurrence, permanent cell line and xenotransplantation tumors. 206 11
We have investigated the anti-metastatic and anti-invasive activities of polypeptide analogues based on the Arg-Gly-Asp (RGD) adhesive signal in
fibronectin
, poly(RGD), poly(RGDS)[Arg-Gly-Asp-Ser] and poly(RGDT)[Arg-Gly-Asp-Thr]. These polypeptides containing repetitive RGD sequences were able to inhibit experimental and spontaneous lung metastases of B16-BL6 cells more effectively than the corresponding monomer peptides. In the spontaneous metastasis model, multiple i.v. administrations of these polymeric peptides before or after surgical excision of the
primary tumor
resulted in a significant reduction of lung tumor colonies. However, there was no significant difference in ability to inhibit spontaneous lung metastasis among poly(RGD), poly(RGDS) and poly(RGDT), although the carboxy-terminal amino acid residue (i.e., Xaa in -RGDXaa-) has been shown to play an important role in the expression of cell adhesive character. The treatment with poly(RGD) substantially prolonged the survival time for mice injected s.c. with B16-BL6 melanoma as compared with the untreated control. We also found that the polypeptides were potently able to inhibit the invasion and migration of tumor cells in vitro. Since these polypeptide analogues showed no antigenicity in the host and had no toxic effect on tumor cells in vitro, they may be potentially useful in the prevention of cancer metastasis.
...
PMID:Anti-metastatic and anti-invasive effects of polymeric Arg-Gly-Asp (RGD) peptide, poly(RGD), and its analogues. 211 67
In a serum-free medium we have established two new human breast carcinoma cell lines from a single
primary tumor
. Cultures were maintained on chemically defined medium CDM3 or on minor modifications of this medium, Dulbecco's modified Eagle medium-Ham's F12 supplemented with epidermal growth factor, insulin, transferrin, estradiol, hydrocortisone, triiodothyronine, cyclic AMP, phosphoethanolamine, ethanolamine,
fibronectin
, fetuin, ascorbic acid, bovine serum albumin, and trace element salts including selenite (Petersen and van Deurs, Cancer Res., 47: 856-866, 1987). Primary cultures comprised both NADPH-neotetrazolium reductase-positive carcinoma cells and NADPH-neotetrazolium reductase-negative cells of stromal appearance, as well as normal epithelial cells (Petersen and van Deurs, Cancer Res., 46: 2013-2020, 1986). In subsequent passages the cells were monitored exclusively using the tumorigenicity assay on nude mice. Two cell lines, one nontumorigenic, HMT-3909S1, and one tumorigenic, HMT-3909S8, were selected from the primary cultures. Selection of S8 through subline S4 required transient supplementation of CDM3 with fetal calf serum. Permanent lines S1 and S8 were maintained on serum-free medium. Further characterization of the two cell lines in terms of normal breast gland differentiation (Petersen and van Deurs, Differentiation, 39: 197-215, 1988) was carried out using immunocytochemistry, immunochemistry, electron microscopy, and cytogenetics. S8 appeared to be identical with the NADPH-neotetrazolium reductase-positive carcinoma cells of the primary cultures, with a particular subpopulation of carcinoma cells in the tumor of origin, and with the tumorigenic cells of the nude mice. This subline was aneuploid, typically epithelial in morphology, and expressed keratins K8 and K18 and the glycoprotein MAM-6, typical of luminal epithelial cells in the normal breast gland. Subline S1 appeared more like the elongated cells in the primary cultures and like a second subpopulation of cells in the carcinoma of origin. However, S1 cells were in fact epithelial, since they expressed keratins. Also, S1 cells seemed to be a triploidation of a cell with close resemblance to S4, while only few cytogenetic differences were found between S4 and S8, suggesting an origin of S1 and S8 via S4 from a single hypothetical stem cell.
...
PMID:Differential tumorigenicity of two autologous human breast carcinoma cell lines, HMT-3909S1 and HMT-3909S8, established in serum-free medium. 215 55
Adhesion has been evaluated for tumor cell populations derived from Kirsten murine sarcoma virus (KiMSV)-transformed BALB/c 3T3 cells responding to substrata coated with intact plasma
fibronectin
(pFN), a family of related proteolytic fragments from pFN or cellular fibronectins (FNs), and the heparan sulfate-binding platelet factor-4 (PF4). Both early-passage KiMSV cells, harboring the viral Kirsten ras oncogene (v-Ki-ras+), and late-passage KiMSV cells, in which most cells have lost the oncogene (v-Ki-ras-), are compared with
primary tumor
and lung metastatic tumor cells after three routes of injection into nude mice; nontumorigenic v-Ki-ras- revertant cells have been cloned from the late-passage KiMSV population. Attachment of early-passage KiMSV,
primary tumor
, and lung metastatic tumor cells was optimal and resistant to soluble RGDS peptide in the medium on intact pFN, on fragment F-155 from pFN containing the RGDS cell-binding domain and the heparinII domain, and on PF4 but decreased for metastatic cells on F110 containing only the RGDS domain (and sensitive to RGDS peptide). Cytoplasmic spreading of early-passage KiMSV and all tumor cells was good to excellent in polygonal patterns on pFN and on F155, while most cells remained round on F110. Responses for KiMSV and tumor cells varied on different heparin-binding proteins; cells remained rounded or detached on F38 derived from pFN or on PF4 but spread effectively with long linear process extension on cellular FN-derived fragments F44 + 47 harboring the extra domaina sequence. That F44 + 47 may contain a new cell-binding site for v-Ki-ras+ cells was also indicated by resistance to bacterial heparitanase in cell responses on F44 + 47 but not on PF4 and extensive catabolism of proteoglycans in the substratum-attached material of these cells. v-Ki-ras- revertant cells, nontumorigenic in nude mice, have reacquired 3T3-like responses to proteolytic fragments, including much more effective spreading on PF4 or on F38 substrata, and have reverted in generating microfilament stress fibers on pFN, a competence lacking in all v-Ki-ras+ cells. These results indicate that (a) v-Ki-ras+ primary and metastatic tumor cells respond similarly to most proteolytic fragments of FNs harboring known binding domains, with a few exceptions; (b) v-Ki-ras gene expression correlates with a new cell surface receptor activity recognized by extra domaina-containing fragments from cellular FNs; and (c) loss of the viral oncogene to generate v-Ki-ras- revertant cells reverts their FN-mediated adhesion responses.
...
PMID:Adhesion of Kirsten-ras+ tumor-progressing and Kirsten-ras- revertant 3T3 cells on fibronectin proteolytic fragments. 216 49
Tumor angiogenesis is a very important process for growth and proliferation of most solid tumors. It insures the delivery of feeding molecules as well as the elimination of degradation products and allows tumoral cells to escape from the
primary tumor
site and the further establishment of metastases. Tumor neovascularisation is the result of a cascade of events primarily related to the properties of endothelial cells of capillaries. The main steps are: a) degradation of capillary basal lamina and destruction of the surrounding tissues, b) endothelial cell proliferation and c) endothelial cell migration towards the tumor site. A number of substances either synthetic or of natural origin are known to stimulate one of the above mentioned steps and/or to induce the production of factors which, in turn, stimulate one or several steps of the cascade. Such molecules can also be synthesized by tumoral cells; indeed they have often been evidenced in the fluids surrounding the tumor site. Many factors remain to be identified and their mechanism of action wait to be elucidated. However, it is already clear that several molecules are involved in the various steps of tumor angiogenesis. They display a coordinated sequential action and their synthesis is induced and controlled by the tumor itself. Amongst others, the following molecules play a role in tumor angiogenesis: degradative enzymes, E-prostaglandins, specific oligopeptides,
fibronectin
and heparin. Furthermore, several metal cations are also involved in tumor angiogenesis.
...
PMID:[Tumor angiogenesis]. 242 24
We investigated that the antimetastatic and antiadhesive activities of peptides based on Arg-Gly-Asp adhesive signal in
fibronectin
could be augmented by their polymerization. Poly(Arg-Gly-Asp), which consists of a repetitive sequence of Arg-Gly-Asp, inhibited lung metastases in C57BL/6 mice more effectively than Arg-Gly-Asp tripeptide was able to do, when coinjected or separately injected with B16-BL6 cells. The adhesion of tumor cells to
fibronectin
was specifically inhibited by adding poly(Arg-Gly-Asp) but not unrelated peptides. In contrast, poly(Arg, Gly, Asp), in which three amino acids are randomly arranged, showed neither inhibition of lung metastases nor any adhesive ability to attach to tumor cells. The inhibitory effect of polymeric peptides containing the Arg-Gly-Asp sequence on lung metastases decreased according to the decreasing repeat units of the Arg-Gly-Asp core sequence. Polymeric peptides with Arg-Gly-Asp entrapped within the liposome membranes also caused a remarkable reduction of metastatic colonies. In a spontaneous metastasis model, multiple i.v. administrations of poly(Arg-Gly-Asp) after tumor inoculation caused the significant reduction of metastatic colonies in the lung but did not affect the growth (size) of
primary tumor
. We found that the polymerization (multivalency) of the Arg-Gly-Asp core sequence was able to augment the inhibition of tumor lung metastases in experimental and spontaneous metastasis models as well as the cell-adhesive property more effectively than a monovalent unit of Arg-Gly-Asp peptide.
...
PMID:Inhibition of the metastasis of murine malignant melanoma by synthetic polymeric peptides containing core sequences of cell-adhesive molecules. 273 23
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