epidermal-growth-factor and Fibrosarcoma

Capsaicin is a cancer-suppressing agent. The aim of our study was to determine the effect of capsaicin on tumor invasion and migration; the possible mechanisms involved in this inhibition were investigated in human fibrosarcoma cells.. We employed invasion, migration and gelatin zymography assays to characterize the effect of capsaicin on HT-1080 cells. Transient transfection assays and immunoblot analysis were performed to study its molecular mechanisms of action. Capsaicin inhibited the epidermal growth factor (EGF)-induced activation of matrix metalloproteinase (MMP)-9 and MMP-2, and further inhibited cell invasion and migration. Capsaicin decreased the EGF-induced expression of MMP-9, MMP-2, and MT1-MMP, but did not alter TIMP-1 and TIMP-2 levels. Capsaicin suppressed EGF-induced c-Jun and c-Fos nuclear translocation, and also abrogated the EGF-induced phosphorylation of EGF receptor (EGFR), focal adhesion kinase (FAK), protein kinase C (PKC), phosphatidylinositol 3-Kinase (PI3K)/Akt, extracellular regulated kinase (ERK)1/2, and JNK1/2, an upstream modulator of AP-1. Furthermore, the EGFR inhibitor inhibited EGF-induced MMP-9 expression, as well as AP-1 activity and cell migration.. Capsaicin inhibited the EGF-induced invasion and migration of human fibrosarcoma cells via EGFR-dependent FAK/Akt, PKC/Raf/ERK, p38 mitogen-activated protein kinase (MAPK), and AP-1 signaling, leading to the down-regulation of MMP-9 expression. These results indicate the role of capsaicin as a potent anti-metastatic agent, which can markedly inhibit the metastatic and invasive capacity of fibrosarcoma cells.

Topics: Antineoplastic Agents, Phytogenic; Capsaicin; Cell Line, Tumor; Cell Movement; Cell Nucleus; Down-Regulation; Epidermal Growth Factor; ErbB Receptors; Fibrosarcoma; Gene Expression Regulation, Neoplastic; Hormone Antagonists; Humans; Matrix Metalloproteinase 14; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Neoplasm Invasiveness; Phosphorylation; Protein Transport; RNA, Messenger; Signal Transduction; Transcription Factor AP-1

The small GTPase RhoA and its downstream effectors, the Rho-associated kinase (Rho-kinase) family, are known to regulate cell morphology, motility, and tumor progression via the regulation of actin cytoskeleton rearrangement. In the present study, we evaluated the role of Rho-kinase in the intracellular endocytic trafficking of ligand-induced phosphorylated epidermal growth factor receptor (pEGFR). We investigated the time course of the internalization fate of EGF-induced pEGFR via the early/late endocytic pathway in human fibrosarcoma cell line HT1080 cells using Y-27632, a selective Rho-kinase inhibitor. We found, using confocal immunofluorescence microscopy and Western blot analysis, a large accumulation of pEGFR in the nuclei of HT1080 cells. In contrast, we observed decreased amounts of the pEGFR-positive staining in the nuclei along with an accumulation of cytosolic pEGFR staining when the cells were incubated for 15-30 min in the presence of Y-27632, implying that an aberrant endocytic trafficking mechanism of pEGFR occurs in HT1080 cells whereby pEGFR might be selectively translocated into the nucleus. Moreover, we demonstrated that after 15-min of stimulation with Texas Red-EGF, increasing numbers of pEGFR-positive staining that had colocalized with Texas Red-EGF-positive punctate staining were seen in the cytoplasm of HT1080 cells but after 30-min of stimulation, most of this staining had disappeared from the cytoplasm and a large accumulation of pEGFR-positive staining appeared in the nucleus. Thus, nuclear accumulation of pEGFR appears to occur in an EGF-dependent manner. In contrast, such nuclear pEGFR-positive staining was not seen in the Y-27632-treated cells. Furthermore, silencing of RhoA or Rho-kinases I/II by sequence specific siRNAs considerably inhibited the EGF-dependent nuclear accumulation of pEGFR. Collectively, these results provide the first evidence that Rho-kinase signaling pathway plays a suppressive role in the intracellular vesicle trafficking of pEGFR via the endocytic pathway and that an increased Rho-kinase activity leads to the attenuation of the normal endocytic vesicular traffic of pEGFR via the early/late endocytic pathway, instead causing pEGFR to be trafficked out of the endocytic vesicles into the nucleus.

Topics: Actin Cytoskeleton; Amides; Blotting, Western; Cell Line, Tumor; Cell Nucleus; Endocytosis; Epidermal Growth Factor; ErbB Receptors; Fibrosarcoma; Gene Silencing; Humans; Ligands; Phosphorylation; Protein Transport; Pyridines; rac1 GTP-Binding Protein; rho-Associated Kinases; RNA, Small Interfering; Signal Transduction

Epidermal growth factor (EGF) signaling is critical in normal and aberrant cellular behavior. Extracellular signal-regulated kinase (ERK) mediates important downstream aspects of EGF signaling. Additionally, EGFR undergoes MEK1-dependent ERK consensus site phosphorylation in response to EGF or cytokines such as growth hormone (GH) and prolactin (PRL). GH- or PRL-induced EGFR phosphorylation alters subsequent EGF-induced EGFR downregulation and signal characteristics in an ERK-dependent fashion. We now use reconstitution to study mutation of the sole EGFR ERK phosphorylation consensus residue, (669)T. CHO-GHR cells, which lack EGFR and express GHR, were stably transfected to express human wild-type or T669A ((669)T changed to alanine) EGFRs at similar abundance. Treatment of cells with GH or EGF caused phosphorylation of WT, but not T669A EGFR, in an ERK activity-dependent fashion that was detected with an antibody that recognizes phosphorylation of ERK consensus sites, indicating that (669)T is required for this phosphorylation. Notably, EGF-induced downregulation of EGFR abundance was much more rapid in cells expressing EGFR T669A vs. WT EGFR. Further, pretreatment with the MEK1/ERK inhibitor PD98059 enhanced EGF-induced EGFR loss in cells expressing WT EGFR, but not EGFR T669A, suggesting that the ERK-dependent effects on EGFR downregulation required phosphorylation of (669)T. In signaling experiments, EGFR T669A displayed enhanced acute (15 min) EGFR tyrosine phosphorylation (reflecting EGFR kinase activity) compared to WT EGFR. Further, acute EGF-induced ubiquitination of WT EGFR was markedly enhanced by PD98059 pretreatment and was increased in EGFR T669A-expressing cells independent of PD98059. These signaling data suggest that ERK-mediated (669)T phosphorylation negatively modulates EGF-induced EGFR kinase activity. We furthered these investigations using a human fibrosarcoma cell line that endogenously expresses EGFR and ErbB-2 and also harbors an activating Ras mutation. In these cells, EGFR was constitutively detected with the ERK consensus site phosphorylation-specific antibody and EGF-induced EGFR downregulation was modest, but was substantially enhanced by pretreatment with MEK1/ERK inhibitor. Collectively, these data indicate that ERK activity, by phosphorylation of a threonine residue in the EGFR juxtamembrane cytoplasmic domain, modulates EGFR trafficking and signaling.

Topics: Amino Acid Sequence; Animals; Antibodies, Monoclonal; CHO Cells; Cricetinae; Cricetulus; Down-Regulation; Epidermal Growth Factor; ErbB Receptors; Extracellular Signal-Regulated MAP Kinases; Fibrosarcoma; Humans; Molecular Sequence Data; Mutant Proteins; Phosphorylation; Phosphothreonine; Phosphotyrosine; Receptor, ErbB-2; Receptors, Somatotropin; Signal Transduction; Ubiquitination

Activation of growth factor receptors by ligand binding leads to an increased expression of c-Myc, a transcriptional regulator for cell proliferation. The activation of transcriptional factors via the activated receptors is thought to be the main role of c-Myc gene expression. We demonstrate here that epidermal growth factor receptor (EGFR)- and fibroblast growth factor receptor (FGFR)-mediated c-Myc induction and cell cycle progression in primary cultured mouse embryonic fibroblasts (MEFs) are abrogated by knockout of the heparin-binding EGF-like growth factor (Hb-egf) gene, or by a metalloproteinase inhibitor, although molecules downstream of the receptors are activated. Induction of c-Myc expression by EGF or basic FGF is recovered in Hb-egf-depleted MEFs by overexpression of wild-type proHB-EGF, but no recovery was observed with an uncleavable mutant of proHB-EGF. The uncleavable mutant also inhibited EGF-induced acetylation of histone H3 at the mouse c-Myc first intron region, which could negatively affect transcriptional activation. We conclude that signal transduction initiated by generation of the carboxyl-terminal fragment of proHB-EGF (HB-EGF-CTF) in the shedding event plays an important intermediary role between growth factor receptor activation and c-Myc gene induction.

Topics: Adenoviridae; Alkaline Phosphatase; Animals; Cell Culture Techniques; Cell Cycle; Cell Line, Tumor; Cells, Cultured; Chromatin Immunoprecipitation; Dose-Response Relationship, Drug; Embryo, Mammalian; Epidermal Growth Factor; Epigenesis, Genetic; ErbB Receptors; Fibroblast Growth Factor 2; Fibroblasts; Fibrosarcoma; Gene Expression; Genes, myc; Heparin; Humans; Keratinocytes; Mice; Mice, Transgenic; Microscopy, Fluorescence; Mutation; Promoter Regions, Genetic; Receptors, Fibroblast Growth Factor; Recombinant Proteins; Transfection

We developed a bioassay to evaluate the phosphorylation status of a fibrosarcoma following systemic administration of the protein tyrosine kinase inhibitor PKI 166. Samples of subcutaneous fibrosarcomas and distant skin were fixed in formalin, sectioned, and stained with several fluorescent antibodies against the epidermal growth factor receptor (EGF-R) and phosphorylated EGF-R. In mice given different doses of PKI 166, the dose-dependent inhibition of phosphorylation of EGF-R in epidermal keratinocytes paralleled that in fibrosarcomas growing subcutaneously, suggesting that skin biopsies can be used as surrogate tissues for distant neoplasms to determine the phosphorylation status of protein tyrosine kinase receptors.

Topics: Animals; Benzimidazoles; Biological Assay; Cell Line, Tumor; Dose-Response Relationship, Drug; Endocytosis; Epidermal Growth Factor; ErbB Receptors; Fibrosarcoma; Keratinocytes; Mice; Mice, Inbred C3H; Microscopy, Fluorescence; Neoplasm Transplantation; Phosphorylation; Pyrimidines; Pyrroles; Specific Pathogen-Free Organisms

Little is known about the regulation of sarcoma proliferation by hormones and/or growth factors. We therefore characterised the in vitro proliferative influence on eight sarcoma cell lines of the platelet-derived growth factor, the insulin-like growth factor 1, triiodothyronine, the epidermal growth factor, the luteinising-hormone-releasing hormone, progesterone, gastrin and 17 beta-oestradiol. The influence of the different factors on the proliferation of sarcoma cell lines was measured by the colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test. Two culture media were studied: (1) a nutritionally poor medium containing 2% of fetal calf serum and (2) a nutritionally rich one containing 5% or 10% FCS both with and without the addition of non-essential amino acids. The results were analysed either by conventional statistical analyses or by a classification method based on a decision-tree approach developed in Machine Learning. This latter method was also compared to other classifiers (such as logistic regression and k nearest neighbours) with respect to its accuracy of classification. Monovariate statistical analysis showed that each of the eight cell lines exhibited sensitivity to at least one factor, and each factor significantly modified the proliferation of five or six of the eight cell lines under study. Of these eight lines one of fibrosarcoma origin was the most "factor-sensitive". Decision-tree-related data analysis enabled the specific pattern of factor sensitivity to be characterised for the three histological types of cell line under study. The effects of hormone and growth factors are significantly influenced by the type of culture medium used. The method used appeared to be an accurate classifier for the kind of data analysed. Sarcoma proliferation can be modulated, at least in vitro, by various hormones and growth factors, and the proliferation of each histopathological type exhibited a distinct sensitivity to different hormone and/or growth-factors.

Topics: Cell Division; Colorimetry; Culture Media; Epidermal Growth Factor; Estradiol; Fibrosarcoma; Gastrins; Gonadotropin-Releasing Hormone; Growth Substances; Hormones; Humans; Insulin-Like Growth Factor I; Leiomyosarcoma; Platelet-Derived Growth Factor; Progesterone; Reproducibility of Results; Rhabdomyosarcoma; Sensitivity and Specificity; Tetrazolium Salts; Thiazoles; Triiodothyronine; Tumor Cells, Cultured

Repair of colonic epithelial erosions requires cell migration. This study aimed to examine the effects of physiologically relevant short-chain fatty acids on migration in colonic epithelial cell lines.. Butyrate, propionate, and acetate were added to confluent monolayers of LIM1215 colon cancer cells after wounding. Migration in circular wounds was assessed after 24 hours.. The migration of LIM1215 cells was stimulated in a concentration-dependent manner by all short-chain fatty acids. In four experiments, 2 mmol/L butyrate, 8 mmol/L propionate, and 16 mmol/L acetate induced 112.6% +/- 6.7%, 98.5% +/- 5.4%, and 63.4% +/- 7.2% (mean +/- SEM) stimulation above control migration, respectively. Their effects were additive at submaximal concentrations and reversible. Butyrate also stimulated migration in two other colon cancer cell lines, Caco-2 and LIM2405. However, butyrate failed to stimulate the migration of nongastrointestinal and nonepithelial cell lines. The stimulatory effect of butyrate required protein and RNA synthesis but was independent of cell proliferation, presence of serum, beta-oxidation, transforming growth factor beta, intracellular acidification, and substratum composition.. In wounded in vitro models of colonic epithelium, short-chain fatty acids promote cell migration. If such an effect occurs in vivo, it would have ramifications for the biology and pathobiology of the colonic mucosa.

Topics: Animals; Caco-2 Cells; Carbon Radioisotopes; Cell Division; Cell Movement; Colonic Neoplasms; Cycloheximide; Dose-Response Relationship, Drug; Epidermal Growth Factor; Epithelial Cells; Epithelium; Fatty Acids, Volatile; Fibroblast Growth Factors; Fibrosarcoma; Humans; Hydrogen-Ion Concentration; L-Lactate Dehydrogenase; Leucine; Lung; Mink; RNA; Thymidine; Transforming Growth Factor beta; Tritium; Tumor Cells, Cultured

The interplay between cyclic AMP (cAMP)-dependent protein kinase A (PKA)- and p21ras-mediated signaling pathways is expected to determine further loss, maintenance, or modulation of differentiation and proliferation of a particular cell. Therefore, the relationship and nature of the cross-talk between these two major signaling systems are of utmost importance to the understanding of these processes in both normal and neoplastic cells. In view of their paramount physiological importance, one would expect the existence of a well-controlled bidirectional interaction between these pathways, which would be more appropriate and in agreement with basic principles of cellular homeostasis. However, based on the discovery that activated PKA may inhibit ras-mediated translocation of c-Raf-1 to the plasma membrane, it is generally accepted that the cross-talk between cAMP/PKA and p21ras-mediated signal transduction pathways is unilateral, i.e., that the activation of PKA regulates growth factor receptor protein tyrosine kinase-mediated signaling. To challenge the validity of a unilateral approach, we decided to test the possible existence of cross-talk of a bidirectional nature between the aforementioned signaling pathways at different stages of malignant differentiation. For that purpose, we investigated the nature of the cross-talk existing between a known receptor protein tyrosine kinase-epidermal growth factor receptor (EGFR) and PKA in highly metastatic and nonmetastatic cloned variants of a murine fibrosarcoma (T-10). Our study revealed the existence of principal differences in PKA activity between metastatic and nonmetastatic cloned fibrosarcoma variants that may be due to the differential expression and membrane translocation of the p21(Ki-ras) small mass G-protein. Most importantly, our experiments have demonstrated the existence of a novel character of interactions between EGFR and PKA, because the ligation of the EGFR by epidermal growth factor in the metastatic variant induced a high activity of PKA. These findings are of prime importance, because they reveal the existence of a new relationship between two major signal transduction pathways in mammalian cells, i.e., the existence of a bilateral interaction between the ras- and cAMP/PKA-mediated signal transduction pathways. Furthermore, the fact that two tumor cell variants originating in the same tumor and differing in their metastatic capacity differ as well in the nature of the cross-talk between major

Topics: 3T3 Cells; Animals; Benzylidene Compounds; Bucladesine; Clone Cells; Culture Media, Serum-Free; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; Enzyme Induction; Enzyme Inhibitors; Epidermal Growth Factor; ErbB Receptors; Fibroblast Growth Factors; Fibrosarcoma; Genetic Variation; Mice; Mice, Inbred C3H; Mice, Inbred C57BL; Neoplasm Metastasis; Nitriles; Proto-Oncogene Proteins p21(ras); Recombinant Proteins; Signal Transduction; Transfection; Tumor Cells, Cultured; Tyrphostins

Overexpression of membrane-type matrix metalloproteinase (MT-MMP-1) results in the activation of both endogenous and exogenous 72-kDa gelatinase. To understand the effects of MT-MMP-1 on 72-kDa gelatinase activation, we analyzed its expression in human fibroblasts and HT-1080 fibrosarcoma cells. Both cell types expressed the MT-MMP-1 mRNA constitutively at a considerable level and treatment of cells with PMA enhanced the expression about 2-3-fold. Concanavalin A treatment increased MT-MMP-1 mRNA levels in fibroblasts about 4-fold. Induction of MT-MMP-1 by phorbol 12-myristate 13-acetate (PMA) required protein synthesis as shown by cycloheximide inhibition. The induction was also inhibited by dexamethasone. Analysis of MT-MMP-1 mRNA stability using actinomycin D indicated that the half-life was rather long and not affected by PMA, suggesting transcriptional regulation. Only HT-1080 cells had significant 72-kDa gelatinase processing activity after treatment with PMA or concanavalin A, while fibroblasts were virtually negative. Immunoblotting analysis of fibroblast lysates indicated that MT-MMP-1 was present mainly in a 60-kDa form. PMA and concanavalin A caused 2-4-fold increases in its protein levels, while in HT-1080 cells PMA, concanavalin A, or overexpression of MT-MMP-1 did not significantly enhance the level of the 60-kDa protein. Instead, an immunoreactive, proteolytically processed 43-kDa form was observed, and its appearance correlated to 72-kDa gelatinase processing activity. Thus 72-kDa gelatinase activation, while enhanced by MT-MMP-1 expression, needs additional co-operating factors.

Topics: Base Sequence; Calcimycin; Cell Line; Collagenases; Concanavalin A; Cycloheximide; Cytokines; Dexamethasone; DNA Primers; Enzyme Activation; Epidermal Growth Factor; Fibroblast Growth Factor 2; Fibroblasts; Fibrosarcoma; Gelatinases; Gene Expression Regulation, Enzymologic; Growth Substances; Humans; Immunoblotting; Interleukin-1; Lung; Matrix Metalloproteinase 1; Molecular Sequence Data; Polymerase Chain Reaction; Recombinant Proteins; RNA, Messenger; Tetradecanoylphorbol Acetate; Transcription, Genetic; Transforming Growth Factor beta; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha

Incubation of a human fibrosarcoma cell line HT-1080 in Li(+)-containing medium inhibited internalization of a fluid marker, horseradish peroxidase (HRP), by more than 80%. The ion inhibited the activity enhanced by Ca2+ or phorbol 12-myristate 13-acetate. We also found that wortmannin (WT), a potent inhibitor of phosphoinositide (PI) 3-kinase (PI 3-k), inhibited the non-stimulated and the two stimulated types of endocytosis to the same extent as Li+. In contrast, neither WT nor Li+ influenced the early internalization of transferrin (Tfn), EGF or platelet-derived growth factor. Neither targeting to early endosomes nor recycling of the once-internalized Tfn was influenced. When the cytoplasmic pH was lowered by chasing cells that had been preincubated with 25 mM NH4Cl in an amiloride-containing Na(+)-free medium, more than 90% of internalization of Tfn in HT-1080 cells was inhibited, while that of HRP was reduced by only 35%. In contrast, WT reduced the uptake of HRP by KB cells by 34%, while 60% of the activity was inhibited by the treatment for cytoplasmic acidification. Comparison of other cells i.e., A-549 and a human diploid cell line Miyajima, indicated that cells showing higher sensitivity to WT were less sensitive to low cytoplasmic pH. These results suggest that, in all the cells studied, bulk fluid is internalized either via a clathrin-independent/PI 3-k-dependent route or via a clathrin-dependent/PI 3-k-independent one, though the ratio varied among them. We also found that internalization of a mAb directed toward the 116 (100)-kDa subunit of vacuolar ATPase [OSW2; Sato and Toyama (1994) J. Cell Biol. 127, 39-53] in the fluid phase was inhibited by WT, but the antibody was still internalized in a surface-bound form. Regardless of the treatment with WT, most of the antibody was transported to endosomes that were associated with Tfn receptor. These results suggest that both internalization routes are targeted to the same early endosomal compartments.

Topics: Ammonium Chloride; Androstadienes; Antibodies, Monoclonal; Calcium; Cell Line; Clathrin; Endocytosis; Endosomes; Enzyme Inhibitors; Epidermal Growth Factor; Fibrosarcoma; Horseradish Peroxidase; Humans; Hydrogen-Ion Concentration; Lithium; Microscopy, Electron; Phosphatidylinositol 3-Kinases; Phosphotransferases (Alcohol Group Acceptor); Platelet-Derived Growth Factor; Proton-Translocating ATPases; Tetradecanoylphorbol Acetate; Transferrin; Tumor Cells, Cultured; Wortmannin

Prostaglandins may inhibit or promote tumor cell replication, depending on the cell system that is investigated. In our laboratory, we have established and characterized four different specific human cancer cell lines. The objectives of this study were to examine and compare the prostaglandin endoperoxide synthase (PG synthase, EC 1.14.99.1) activity of these cell lines by measuring the conversion of arachidonate to 3H-PGE2 and 3H-PGF2 alpha. We found that the oral epidermal carcinoma cell line (OEC-M1) had a moderate degree of PG synthase activity. Enzyme activity could be partially blocked (statistically significant) by the addition of epidermal growth factor (EGF) at 20 ng/mL and almost completely inhibited by platelet-derived growth factor at (PDGF) 20 mU/mL. By contrast, we discovered that the human breast adenocarcinoma cell line (BC-M1) did not contain significant PG synthase, and enzyme activity could be significantly activated by the addition of epidermal growth factor at 20 ng/mL and platelet-derived growth factor at 20 mU/mL. We also found that the human stomach adenocarcinoma cell line (SCM-1) had a significant amount of PG synthase activity, and these PG synthase activities were not activated or inhibited by EGF at 20 ng/mL or PDGF at 20 mU/mL. Furthermore, the human fibrosarcoma (FS-M1) cell line also contained a moderate degree of PG synthase activity, which could be significantly inhibited by PDGF at 20 mU/mL but was not inhibited by EGF at 20 ng/mL. The results suggest that EGF and PDGF may be involved in the regulation of the PG synthase activities of human oral, breast, stomach, and fibrosarcoma cancer cells.

Topics: Adenocarcinoma; Breast Neoplasms; Buttocks; Carcinoma, Squamous Cell; Chromatography, Thin Layer; Cyclooxygenase Inhibitors; Dinoprost; Dinoprostone; Enzyme Activation; Epidermal Growth Factor; Female; Fibrosarcoma; Gingival Neoplasms; Humans; Organ Specificity; Platelet-Derived Growth Factor; Prostaglandin-Endoperoxide Synthases; Stomach Neoplasms; Tumor Cells, Cultured

The effects of various glycosaminoglycans (GAGs) on the growth rate of normal fibroblasts and a fibrosarcoma cell line (HT 1080) were examined. Cells were grown in 96-well microplates in the absence or presence of serum mitogens, epidermal (EGF), platelet-derived (PDGF), acidic fibroblast (aFGF), or basic fibroblast growth factor (bFGF). Cell number was measured by using crystal violet to stain cell nuclei (Westergren-Thorsson, G., Onnervik, P.-O., Fransson, L.-A., and Malmström, A. J. Cell. Phys. 147, 523-530, 1991) and also by using a Coulter counter. In the presence of serum mitogens, L-iduronate (IdoA)-rich GAGs, such as dermatan sulfate, heparin, and highly sulfated heparan sulfate, inhibited proliferation of normal cells (25-35%), whereas HT 1080 cells were unaffected or slightly stimulated. Ham's F-12 supplemented with insulin and transferrin but without growth factors was able to support growth of both cell types. Under these conditions, the IdoA-rich GAGs still suppressed growth of normal cells (40-55%), whereas HT 1080 cells again responded poorly. When growth factors were added proliferation of normal fibroblasts was further stimulated, EGF being the most effective. In the presence of either EGF, PDGF, or bFGF, IdoA-rich GAGs had a sustained inhibitory effect on normal fibroblasts (30-50% at concentrations at or above 10 micrograms/ml). However, in the presence of aFGF, both IdoA-rich and IdoA-poor heparan sulfates enhanced growth (nearly twofold after prolonged exposure) suggesting a stabilization of this growth factor. In general, IdoA-rich GAGs appear to inhibit proliferation of normal cells irrespective of the type of growth factor used. Therefore, GAGs are likely to act directly on cell-derived regulatory components, either before or after internalization. As fibrosarcoma cells were much less sensitive to growth inhibition, they may contain altered receptors for GAGs.

Topics: Blood Proteins; Cell Division; Cells, Cultured; Dermatan Sulfate; Epidermal Growth Factor; Fibroblast Growth Factor 1; Fibroblast Growth Factor 2; Fibroblasts; Fibrosarcoma; Glycosaminoglycans; Growth Inhibitors; Growth Substances; Heparitin Sulfate; Humans; Iduronic Acid; Lung; Mitogens; Platelet-Derived Growth Factor; Tumor Cells, Cultured

Human fibrosarcoma cells derived from a patient with multiple metastases extensively degrade artificial basement membranes (BM) and secrete interstitial type of collagenase, a proteolytic enzyme responsible for degradation of type I collagen. Exposure of invasive cell line to TGF beta abrogates destruction of BM.TGF beta reduces collagenase activity and stimulates specific metalloproteinase inhibitor (TIMP) in invasive tumor cells. We preassume that TGF beta could play a protective role in tumor invasion.

Topics: Basement Membrane; Cells, Cultured; Epidermal Growth Factor; Fibroblast Growth Factors; Fibrosarcoma; Glycoproteins; Humans; Metalloendopeptidases; Microbial Collagenase; Neoplasm Invasiveness; Tissue Inhibitor of Metalloproteinases; Transforming Growth Factor beta; Tumor Cells, Cultured

Cell lines with varying tumorigenic and metastatic potentials have been obtained by transformation of 10T 1/2 fibroblasts using radiation or transfection with T-24 H-ras. We have observed an inverse relationship between metastatic potential and dependence on serum for growth. The effects of basic fibroblast growth factor, platelet-derived growth factor, epidermal growth factor, and transforming growth factor-beta 1 (TGF-beta 1) on these lines were then examined to determine if the changes in the serum dependence of metastatic cells may be due to altered responsiveness to specific growth factors (GFs). Cells were grown in monolayer culture and DNA synthesis was measured by [CH3-3H]thymidine incorporation experiments. Both metastatic and nonmetastatic cells were shown to be equivalent in their diminished responsiveness to basic fibroblast growth factor, platelet-derived growth factor, and epidermal growth factor as compared to their nontransformed, parental 10T 1/2 cells. However, a unique response of metastatic cells to TGF-beta 1 was identified. While TGF-beta 1 inhibited DNA synthesis in 10T 1/2 cells and a nonmetastatic tumor, cells with intermediate to high metastatic ability were stimulated up to 5.8-fold by TGF-beta 1. Interestingly, epidermal growth factor abrogated the TGF-beta 1 inhibition of the parental 10T 1/2 cells, but had no effect on the TGF-beta 1 response of any metastatic line. Therefore, metastatic but not nonmetastatic cells, demonstrated a dramatically altered sensitivity to TGF-beta 1, a response which may be important in determining metastatic potential.

Topics: Animals; Cell Line; Cell Transformation, Neoplastic; DNA Replication; Epidermal Growth Factor; Fibroblast Growth Factors; Fibroblasts; Fibrosarcoma; Genes, ras; Growth Substances; Mice; Mice, Inbred BALB C; Neoplasm Metastasis; Platelet-Derived Growth Factor; Transforming Growth Factors

We have studied the effect of laminin on type IV collagenolytic activity elaborated by malignant cells in culture. Laminin (at concentrations of 4-8 micrograms/ml) added to serum-free culture supernatants of subconfluent A2058 human melanoma cells significantly increased the release of the type IV collagenolytic activity (200-300%). The induction of type IV collagenase was more pronounced (580%) using a fragment of laminin which binds to the cell surface laminin receptor. A monoclonal antibody against the human laminin receptor blocked the effect of laminin on type IV collagenase, suggesting that occupation of the laminin receptor may be necessary for the effect. Increase in the type IV collagenolytic activity mediated by laminin was also demonstrated in two other malignant cell lines, HT fibrosarcoma (168%) and mouse melanoma (B16-F10) (271%). The increase in type IV collagenase was found to be specific for laminin because another cell-binding matrix protein, fibronectin, did not have any effect, and epidermal growth factor and transferrin actually decreased the type IV collagenase in human melanoma culture medium (epidermal growth factor, 50% at 20 ng/ml; and transferrin, 20% at 10 micrograms/ml). These studies suggest that tumor cell binding to laminin, which comprises the first step of basement membrane invasion, will induce the second step, namely the collagenolytic dissolution of the basement membrane.

Topics: Animals; Antibodies, Monoclonal; Cells, Cultured; Epidermal Growth Factor; Fibronectins; Fibrosarcoma; Humans; Laminin; Melanoma; Mice; Microbial Collagenase; Neoplasm Invasiveness; Neoplasm Proteins; Peptide Fragments; Receptors, Immunologic; Receptors, Laminin; Secretory Rate; Transferrin

Using HSDM1 C1 cell line derived from the mouse fibrosarcoma which synthesizes and secretes prostaglandin (PG) E2, specific binding sites for epidermal growth factor (EGF), a potent growth stimulator of many tissues, and its effect on PGE2 production by cultured tumor cells were studied. HSDM1 C1 cell line possessed specific, high-affinity receptors for EGF: Kd (5.5 X 10(-10 M) and binding capacity (17,650 sites/cell). EGF significantly stimulated PGE2 production in HSDM1 C1 line cultured in serum-free medium for 24 h in a dose-dependent manner; a 2.5-fold increase over control was induced by as little as 0.1 ng/ml and the maximal effect (3.5-fold increase) by 1 ng/ml. Its stimulatory effect on PGE2 production was completely blocked by indomethacin, an inhibitor of PG biosynthesis. These data suggest that EGF may be involved in modulation of synthesis and/or secretion of PGE2, a potent bone-resorbing factor, by the tumors which may partly contribute to hypercalcemia in certain types of neoplasms.

Topics: Animals; Cell Line; Dinoprostone; Epidermal Growth Factor; ErbB Receptors; Fibrosarcoma; Indomethacin; Kinetics; Mice; Prostaglandins E; Receptors, Cell Surface

We describe a mycoplasma-free human fibrosarcoma cell line, MR-83, which grows readily in liquid culture and as clones in semi-solid agar with a plating efficiency of about 0.5%. It has a stable karyotype consisting of a modal number of 49-51 chromosomes, with two translocations and a deletion. The cell line shows resistance to adriamycin in semi-solid agar assay, and responds to Epidermal Growth Factor (EGF) by increased DNA synthesis, as measured by thymidine uptake.

Topics: Cell Division; Cell Line; Cell Survival; Chromosome Aberrations; Clone Cells; Doxorubicin; Drug Resistance; Epidermal Growth Factor; Fibrosarcoma; Humans; Karyotyping

Topics: Binding, Competitive; Cell Line; Chromatography, Gel; Culture Media; DNA; Epidermal Growth Factor; Female; Fibrosarcoma; Growth Substances; Humans; Peptide Biosynthesis; Radioligand Assay; Receptors, Cell Surface; Thymidine

Topics: Cell Line; Cell Transformation, Neoplastic; Cells, Cultured; Epidermal Growth Factor; Fibroblasts; Fibrosarcoma; Gammaretrovirus; Growth Substances; Oncogenic Viruses; Peptides; Receptors, Drug; Sarcoma Viruses, Feline; Sarcoma Viruses, Murine