Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A tumor cell-derived, collagenase stimulatory factor (TCSF), previously isolated and purified from LX-1 human lung carcinoma cells and judged by immunoblotting and SDS-PAGE to contain a single protein of approximately 58 kDa, has been further analyzed for its biological activity and composition. Three significant new findings have been made. First, the biological activity of TCSF preparations was shown definitively to reside in the 58-kDa protein. This was achieved in two ways: (a) a polyclonal antibody was raised against the 58-kDa protein, after excision from an SDS-PAGE gel, and shown to inhibit the stimulation of fibroblast collagenase production by TCSF preparations; (b) the 58-kDa protein was eluted from a transblot of purified TCSF and shown to stimulate fibroblast collagenase production. Second, partial sequencing of the 58-kDa protein revealed no significant homologies with other known collagenase stimulatory factors. Third, purified TCSF was found, on transblotting to Immobilon, to contain a doublet of 58 kDa (TCSF1) and 54 kDa (TCSF2) proteins; the former was present in higher concentration than the latter. N-terminal amino acid sequencing of the two intact proteins and of four corresponding pairs of tryptic peptides derived from the two proteins showed identity in each case, indicating that TCSF1 and TCSF2 are very similar in composition. However, TCSF1 but not TCSF2 stimulated fibroblast collagenase production, confirming that the 58-kDa protein is the major active component of TCSF preparations.
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PMID:Partial sequencing and characterization of the tumor cell-derived collagenase stimulatory factor. 184 36

Laminin is a large multidomain glycoprotein with diverse biological activities which include stimulation of neurite outgrowth, enhancement of tumor metastasis, and promotion of cell growth, adhesion, and differentiation. A 19 amino acid synthetic peptide derived from the E8 fragment of the laminin A chain (Cys-Ser-Arg-Ala-Arg-Lys-Gln-Ala-Ala-Ser-Ile-Lys-Val-Ala-Val-Ser-Ala-Asp -Arg- NH2) was identified which promotes metastasis and stimulates collagenase IV activity in the culture medium of B16 melanoma cells (Kanemoto et al., 1990). We report that this peptide, here designated LamA2091-2108, is also a potent stimulator of tissue plasminogen activator (t-PA)-catalyzed plasminogen activation, resulting in a 22-fold increase in the kcat/Km of the activation reaction. The activity of purified type I and type IV collagenase was inhibited by LamA2091-2108 with IC50 values of 3 and 43 microM, respectively. These data support an alternative mechanism for the appearance of collagenase activity in the culture media of melanoma cells, namely, that the peptide stimulates plasminogen activation, subsequently generating collagenase activity.
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PMID:Modulation of plasminogen activation and type IV collagenase activity by a synthetic peptide derived from the laminin A chain. 184 24

Mouse colon 26 tumor cells were shown to produce collagenase inhibitor in culture. The inhibitor was purified more than 2,000-fold from the culture medium by passage through DE-52 cellulose, CM-52 cellulose, Ultrogel AcA 54, Con A-Sepharose, and Sephadex G-50 Superfine columns. The inhibitor did not bind to Con A-Sepharose as do most other collagenase inhibitors. The inhibitor showed a single band (Mr = 20.5 k) on sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis, and inhibitory activity against interstitial collagenases and gelatinases, except for bacterial collagenase. Double-immunodiffusion analysis using monospecific anti-serum against tissue inhibitor of metalloproteinases (TIMP) from bovine dental pulp showed that colon 26 inhibitor did not cross-react immunologically with the pulp inhibitor. NH2-Terminal protein sequence data were obtained for the first 36 residues of the colon 26 inhibitor, and the first 20 of them exhibited a sequence almost identical with that of a new TIMP recently designated as TIMP-2.
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PMID:Purification and characterization of a new tissue inhibitor of metalloproteinases (TIMP-2) from mouse colon 26 tumor cells. 166 27

The in vitro succinate dehydrogenase inhibition (SDI) test was adapted to be used with microtiter plates and this microtiter SDI (mSDI) test was evaluated for clinical use of chemosensitivity testing, as compared to findings with the SDI test. The optimal conditions of the mSDI test were determined: (1) 2-5 x 10(4) cells/well; (2) enzymatic disaggregation of solid tumors with the use of a mixture of 0.2% pronase, 0.25% collagenase, 0.1% DNase for 20 min at 37 degrees C; (3) addition of 10 mM sodium succinate in the colorimetric reaction; and (4) use of dimethyl sulfoxide (DMSO) as a solvent for extraction of formazan product. Good correlations were observed between the mSDI and the SDI tests when S-180 cells (r = 0.890-0.996) or 16 human fresh tumor cells (r = 0.731-0.999) were exposed to six anti-cancer drugs (carboquone, adriamycin, mitomycin C, aclacinomycin A, cisplatin, 5-fluorouracil). Thus, the mSDI test facilitates testing of a large number of drugs with minimal amounts of specimens, and is expected to replace the SDI test for chemosensitivity testing of clinical tumor cells.
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PMID:The microtiter SDI test is more advantageous than the SDI test for assessing the chemosensitivity of human tumor cells. 195 59

Human collagenase gene expression is regulated transcriptionally and is inducible by various mitogens in many cell types. To investigate the molecular mechanisms of this response, we examined the effects on collagenase gene expression of okadaic acid, a non-12-O-tetradecanoyl-phorbol-13-acetate (TPA)-type tumor promoter, which induces apparent "activation" of protein kinases by inhibition of protein phosphatases. Steady state levels of collagenase mRNA were markedly increased by okadaic acid treatment. We show that the AP-1 consensus sequence in the collagenase promoter is required for the induction of collagenase gene expression by okadaic acid, even though sequences upstream of the AP-1 consensus site have an additive effect. We also examined the regulation by okadaic acid of expression of the components of the AP-1 complex, c-fos and c-jun. c-fos expression is dramatically stimulated by okadaic acid, whereas c-jun expression is stimulated to a lesser extent. Induction of c-fos gene mRNA occurs through a region known to contain multiple regulatory elements. These results suggest that phosphorylation regulates collagenase gene expression mediated by an AP-1 binding site.
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PMID:Regulation of collagenase gene expression by okadaic acid, an inhibitor of protein phosphatases. 196 42

The hypothesis that activation of the signal transduction pathways by environmental stress may lead to genetic instability was tested. Mouse T-lymphoma cells, GRSL13, were treated with the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). The induction of transcription of c-fos, fosB, c-jun, junB and collagenase was studied as well as the mutation rate in the progeny of treated cells. It was found that mRNA levels of fosB, junB and collagenase, all known to be involved in the growth factor signal transduction pathway, were enhanced. No transcription of c-fos and c-jun was observed in control and TPA-treated cells. These results suggest that transcription of c-fos is not a prerequisite for the induction of transcription of collagenase. The degree of induction of the signal transduction pathway was dependent on culture conditions of the treated cells, growing cells having less response than stationary cells. The mutation rate was significantly enhanced in the progeny of TPA-treated cells from 4.2 X 10(-7) to 9.8 X 10(-7)/cell/generation. Fluctuation analysis showed that TPA leads to a temporary enhancement of the mutation rate up to the eighth generation after treatment. The enhancement of the mutation rate is less apparent in growing cells than in stationary cells (1.8- and 2.9-fold respectively) which, because the signal transduction pathways are less induced in growing cells than in stationary cells, is in agreement with the hypothesis that induction of the signal transduction pathway leads to genetic instability.
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PMID:Concomitant induction of signal transduction pathways and genetic instability by the tumor promoter 12-O-tetradecanoylphorbol-13-acetate. 200 94

Implantation is a crucial step in human reproduction. Disturbances of this process are responsible for pregnancy failure after both in vivo and in vitro fertilization. The endometrium provides the implanting embryo with a unique substratum where the embryo communicates with biochemical signals, attaches itself, penetrates and grows without blood circulation. The highly proliferative phase of the cytotrophoblast, during early human embryogenesis, may be due to endogenous production of growth factors that may establish autocrine/short range paracrine stimulator loops which explain the tumor-like properties of these tissues. Endometrial BM penetration and stroma invasion may be due to the proteolytic capability of the human embryo. It is suggested that collagenase and the urokinase-like plasminogen activator are responsible for this activity. To clarify the molecular mechanisms involved in human embryo implantation several models are suggested: culture of blastocysts, culture of endometrial cells, and endometrial explant co-culture. Human blastocysts cultured with whole perfused human uteri make it possible to recognize some aspects of the entire implantation process and give us the possibility of improving the benefits provided by new technologies in reproductive medicine and reducing embryonic loss at an early stage.
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PMID:Factors regulating interaction between trophoblast and human endometrium. 206 79

Isolated mouse calvarial cells having phenotypic characteristics of osteoblasts, mouse parietal bone segments, mouse serum, and control mouse lung fibroblasts were extracted in NaCl and ultrafiltered to recover final concentrates having nominal molecular weights between 50,000 and 1000 daltons. Final concentrates of osteoblasts and bone but not of serum or control fibroblasts were positive for the inhibition of trypsin degradation of fibrin. Osteoblast final concentrates inhibited trypsin hydrolysis of the synthetic substrate p-tosyl-L-arginine methyl ester. Osteoblast and bone final concentrates comigrated with Trasylol but were electrophoretically distinct from alpha 1-antiproteinase. Final concentrates of osteoblast and bone extracts did not inhibit tadpole collagenase using the [3H]glycine-labeled diffuse chick collagen fibril assay. High-performance liquid chromatography (HPLC) of osteoblast final concentrates after purification using immobilized trypsin affinity chromatography revealed the presence of a major peak that was positive for the inhibition of trypsin. Molecular weight determination by HPLC indicated that the inhibitor(s) range in nominal molecular weight from 4300 to 5100 daltons. The presence of low-molecular-weight serine proteinase inhibitory activity in bone suggests its participation in the regulation of bone resorption through the regulation of enzyme activation of collagenase, and possibly its role in defense against bone matrix enzymatic degradation during tumor cell invasion.
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PMID:Osteoblast low-molecular-weight proteinase inhibitor. I. Isolation and characterization of activity from osteoblastic cells and bone. 210 97

Over the past several years, many tumor markers, including cell surface antigens, T-antigen, ras p55, and ras p52 proteins, have been studied as potential tumor markers of bladder cancer. The lack of specificity and inconsistency of these markers led us to develop a new method for studying the urinary excretion of autocrine motility factor (uAMF) and tumor cell collagenase stimulating factor (TCSF) in 24-hour and first morning voided specimens. AMF is a glycoprotein secreted by the malignant cells and is responsible for cell locomotion, a key event in invasion and metastases of the malignant cells. TCSF is a membrane bound glycoprotein of tumor cells that stimulates fibroblast collagenase production. We have utilized an enzyme-linked immunoabsorption assay to detect the levels of uAMF and TCSF in urine samples collected from normal volunteers, patients with benign diseases, and patients with bladder cancer. Our data indicate that urinary concentrations of uAMF and TCSF are elevated in patients with bladder cancer. Furthermore, the levels of uAMF and TCSF are more elevated in invasive tumors as compared with benign counterparts. We have localized uAMF and TCSF in bladder cancer cells, utilizing immunohistologic techniques.
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PMID:A new method for evaluation of urinary autocrine motility factor and tumor cell collagenase stimulating factor as markers for urinary tract cancers. 212 27

Ten cases of malignant mesothelioma (MM), as diagnosed by clinical history and light and electron microscopy, were studied with polyclonal antibodies directed against the basement membrane-specific proteins, type IV collagen and laminin, as well as with monoclonal antibodies which recognize two epitopes of the laminin receptor (LR). All formalin-fixed, paraffin-embedded mesothelioma tissues examined demonstrated intracytoplasmic immunoreactivity for the basement membrane proteins. Extracellular staining was minimal, analogous to the staining reactions observed in adenocarcinomas of the breast and lung, which on light microscopy mimicked the morphologic appearance of MM. Similarly, LRs were identified on MM cells by intense positive staining. Immunoreactivity was also evident on nonneoplastic mesothelioma and adenocarcinoma cells but with greater heterogeneity and less intensity. It may be concluded from these results that (a) malignant mesotheliomas have the ability to synthesize components of the basement membrane; (b) enhanced attachment to extracellular matrix by MM would be anticipated as laminin receptors are present in large numbers on the surface of mesothelioma cells; (c) the reason for lack of intensiveness by MM cells remains speculative; type IV-specific collagenase may play a role in regulating this function in these tumor cells.
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PMID:Immunoreactivity in malignant mesotheliomas with antibodies to basement membrane components and their receptors. 213 26


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