Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0178874 (tumor progression)
 40,807 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have previously demonstrated that neuroblastoma cells increase the expression of interleukin-6 by bone marrow stromal cells and that stimulation does not require cell-cell contact. In this study we report the purification and identification of a protein secreted by neuroblastoma cells that stimulates interleukin-6 production by stromal cells. Using a series of chromatographic purification steps including heparin-affinity, ion exchange, and molecular sieve chromatography followed by trypsin digestion and liquid chromatography tandem mass spectrometry, we identified in serum-free conditioned medium of neuroblastoma cells several secreted peptides including galectin-3-binding protein, also known as 90-kDa Mac-2-binding protein. We demonstrated the presence of the galectin-3-binding protein in the conditioned medium of several neuroblastoma cell lines and in chromatographic fractions with interleukin-6 stimulatory activity. Consistently, bone marrow stromal cells express galectin-3, the receptor for galectin-3-binding protein. Supporting a role for galectin-3-binding protein in stimulating interleukin-6 expression in bone marrow stromal cells, we observed that recombinant galectin-3-binding protein stimulated interleukin-6 expression in these cells and that interleukin-6 stimulation by neuroblastoma-conditioned medium was inhibited in the presence of lactose or a neutralizing anti-galectin-3 antibody. Down-regulation of galectin-3-binding protein expression in neuroblastoma cells also decreased the interleukin-6 stimulatory activity of the conditioned medium on bone marrow stromal cells. We also provide evidence that stimulation of interleukin-6 by galectin-3-binding protein involves activation of the Erk1/2 pathway. The data, thus, identifies galectin-3-binding protein as a factor secreted by neuroblastoma cells that stimulates the expression of interleukin-6 in bone marrow stromal cells and provides a novel function for this protein in cancer progression.
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PMID:Identification of galectin-3-binding protein as a factor secreted by tumor cells that stimulates interleukin-6 expression in the bone marrow stroma. 1845 Jul 43

The supporting role of proteases in tumor progression and invasion is well known; however, the use of proteases as therapeutic agents has also been demonstrated. In this article, the authors report on the differential effects of exogenous serine proteases on the motility of tumor and normal cells. The treatment of normal and tumor cells with a single dose of pancreatic serine proteases, trypsin (TR) and chymotrypsin (CH), leads to a concentration-dependent response by cells, first accelerating and then slowing mobility. Tumor cells are 10 to 20 times more sensitive to exogenous TR/CH, suggesting that a single dose of proteases may cause discordant movements of normal and tumor cells within the tumor environment. The inhibitory effects of TR on cell motility are contradicted by thrombin (TH), particularly in the regulation of normal cells' migration. The purpose of this investigation was to ascertain the role of protease-activated receptors (PARs) in terms of normal and tumor cell motility. Duplicate treatments with proteases resulted in diminished mobility of both normal and tumor cells. Repeated application of TR and TH in 1-hour treatment intervals initially desensitizes cell surface PARs. However, cell surface PARs reappear regardless of subsequent protease treatments in both normal and tumor cells. The resensitization process is retarded in tumor cells when compared with normal cells. This is evidenced by lower expression of PARs as well as by their relocalization at the tumor cell surfaces. Under these conditions, normal cells remain responsive to exogenous proteases in terms of cell motility. Exogenous proteases do not modulate motility of repeatedly stimulated tumor cells, and consequently, the migration of tumor cells appears disconnected from the PAR signaling pathways. The use of activating peptides in lieu of the cognate proteases for a given PAR system indicated that proteases may act through additional targets not regulated by PAR signaling. We hypothesize that the divergent migration patterns of normal and tumor cells due to exposure to proteases is in part mediated by PARs. Thus, treatment with exogenous proteases may cause rearrangement of the tumor and stromal cells within the tumor microenvironment. Such topographical effects may lead to the inhibition of tumor progression and metastasis development.
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PMID:Differential effects of serine proteases on the migration of normal and tumor cells: implications for tumor microenvironment. 1911 24

Mast cells (MCs) display a diversity of roles that may contribute to the stromal microenvironment alterations during tumor progression. The aim of this study was to investigate MC populations expressing tryptase and c-kit in lip squamous cell carcinoma (lip SCC) (n=37), actinic cheilitis (AC) (n=15) and normal lip mucosa (control) (n=6), as well as their relationship with microscopic parameters (collagen degeneration, elastin changes, angiogenesis and proliferative index). Tryptase, c-kit, CD31 and Ki-67 expressions were analyzed by means of immunohistochemistry and collagen and elastic fibers were visualized with Picrosirus and Verhoeff's stain, respectively. The numbers of tryptase+ MC were significantly higher in lip SCC when compared with control (P=0.01), while a similar density of these cells was observed in AC and lip SCC (P=0.09). The density of c-kit+ MC was similar in all groups examined (P=0.65). MC migration (c-kit+/Tryptase+ relationship) was 69% in lip SCC, 60% in AC and 100% in control. The number of CD31+ blood vessels was significantly higher in the lip SCC when compared with control and AC (P<0.01). The increase of MCs and angiogenesis in lip SCC may reflect an important modification in the tumor microenvironment during squamous photo-carcinogenesis.
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PMID:Density and migration of mast cells in lip squamous cell carcinoma and actinic cheilitis. 1922 48

Human serine proteinase inhibitor Kazal-type 2 (SPINK2) functions as a trypsin/acrosin inhibitor and is synthesized mainly in the testis and seminal vesicle where its activity is engaged in fertility. The SPINK2 protein contains a typical Kazal domain composed by six cysteine residues forming three disulfide bridges. The expression of SPINK2 is closely related to cancer such as lymphomas, in that a high transcript level of SPINK2 in patients with primary cutaneous follicle center cell lymphomas have better prognosis with lower mortality. To clarify the role of SPINK2 in cancer, we performed quantitative real-time PCR and showed that the expression level of SPINK2 is significantly elevated in most leukemia cell lines except B-lymphoblast TK-6 cells. The molecular function and structural features of SPINK2 were also investigated by employing the recombinant active and mutant inactive SPINK2 proteins to determine its key P2-P2' (Pro(23)-Arg(24)-His(25)-Phe(26)) active site. The inhibition assay results demonstrated that Arg(24) at the P1 site is crucial for the specificity of SPINK2 on target enzyme. Although His(25) at the P1' and Phe(26) at the P2' residues are also involved in trypsin-SPINK2 interaction, Pro(23) at the P2 site may not be directly participated in interacting with trypsin. In addition, we determined the 3D solution structure of SPINK2 and used this structure to predict the SPINK2-proteinase complex structure and binding properties. These studies not only provide critical information about the structural properties and biophysical features of the SPINK2 proteinase inhibitor, but also suggest its important role in tumor progression and response to treatment.
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PMID:Identification of trypsin-inhibitory site and structure determination of human SPINK2 serine proteinase inhibitor. 1942 58

Ecotin is a bidentate, fold-specific inhibitor of mammalian serine-proteases produced by Escherichia coli. This molecule may be engineered to increase and/or change its affinity and specificity providing significant biotechnological potential. Since ecotin binds tightly to serine proteases of the trypsin fold, it may help to identify the role of these enzymes in different biological processes. In this work, we tested ecotin variants as an affinity purification reagent for identifying enzymes in samples of tumor progression and mammary gland involution. Initially, we used a commercial source of urokinase-type plasminogen activator (u-PA) that remained fully active after elution from an affinity column of the ecotin variant (M84R, M85R). We then successfully identified u-PA from more complex mixtures including lysates from a prostate cancer cell line and involuting mouse mammary glands. Interestingly, a membrane-type serine protease 1 was isolated from the Triton X-100-solubilized PC-3 cell lysates, and surprisingly, haptoglobin, a serine-protease homolog protein, was also identified in mammary gland lysates and in blood. Haptoglobin does not prevent ecotin inhibition of u-PA, but it may act as a carrier within blood when ecotin is used in vivo. Finally, this affinity purification matrix was also able to identify a thrombin-like enzyme from snake venom using an ecotin variant directed against thrombin. Overall, the ecotin variants acted as robust tools for the isolation and characterization of proteins with a trypsin fold. Thus, they may assist in the understanding of the role of these serine proteases and homologous proteins in different biological processes.
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PMID:Engineering ecotin for identifying proteins with a trypsin fold. 1972 73

Protease-Activated Receptor-2 (PAR2) has been implicated through genetic knockout mice with cytokine regulation and arthritis development. Many studies have associated PAR2 with inflammatory conditions (arthritis, airways inflammation, IBD) and key events in tumor progression (angiogenesis, metastasis), but they have relied heavily on the use of single agonists to identify physiological roles for PAR2. However such probes are now known not to be highly selective for PAR2, and thus precisely what PAR2 does and what mechanisms of downstream regulation are truly affected remain obscure. Effects of PAR2 activation on gene expression in Human Embryonic Kidney cells (HEK293), a commonly studied cell line in PAR2 research, were investigated here by comparing 19,000 human genes for intersecting up- or down-regulation by both trypsin (an endogenous protease that activates PAR2) and a PAR2 activating hexapeptide (2f-LIGRLO-NH(2)). Among 2,500 human genes regulated similarly by both agonists, there were clear associations between PAR2 activation and cellular metabolism (1,000 genes), the cell cycle, the MAPK pathway, HDAC and sirtuin enzymes, inflammatory cytokines, and anti-complement function. PAR-2 activation up-regulated four genes more than 5 fold (DUSP6, WWOX, AREG, SERPINB2) and down-regulated another six genes more than 3 fold (TXNIP, RARG, ITGB4, CTSD, MSC and TM4SF15). Both PAR2 and PAR1 activation resulted in up-regulated expression of several genes (CD44, FOSL1, TNFRSF12A, RAB3A, COPEB, CORO1C, THBS1, SDC4) known to be important in cancer. This is the first widespread profiling of specific activation of PAR2 and provides a valuable platform for better understanding key mechanistic roles of PAR2 in human physiology. Results clearly support the development of both antagonists and agonists of human PAR2 as potential disease modifying therapeutic agents.
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PMID:Profiling gene expression induced by protease-activated receptor 2 (PAR2) activation in human kidney cells. 2107 96

In this study, we correlated the number of tryptase-reactive mast cells with the number of CD8-positive T cells in human endometrial adenocarcinoma biopsy specimens by means of immunohistochemical techniques. Results have shown that CD8-positive T cell counts correlate to tryptase-positive mast cell counts and that these parameters increase in accordance with the tumor progression of human endometrial carcinoma. These data suggest that inhibition of inflammation or manipulation of inflammatory resolution pathways may be a new therapeutic approach for the treatment of endometrial adenocarcinoma.
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PMID:Tryptase-positive mast cells and CD8-positive T cells in human endometrial cancer. 2170 49

Microvesicles (MVs) have been shown to affect the physiology of neighboring recipient cells in various ways. They play an important role in tumor progression/metastasis and angiogenesis in cancer and may be useful therapeutic tools, as well as a mechanism of cell-to-cell communication. They have been visioned as an important biomarker or biomarker source for the detection of different diseases. Human saliva is a biological fluid with enormous diagnostic potential, which harbors plenty of salivary MVs. The goal of this study is to investigate the proteomic profiling of MVs in human saliva through a simple preparation procedure by using filtration and centrifugation. Gel electrophoresis was combined with LC-MS/MS (liquid chromatography-mass spectrometry) for the proteomic analysis of MVs. After SDS-PAGE (sodium dodecyl sulfate polyacrylamide gel electrophoresis) protein separation, the whole lane was cut into 25 bands, and each band was subjected to in-gel trypsin digestion. The peptides extracted from each band were loaded to LC-MS/MS for protein identification. Through protein database search, 63 proteins were identified for human salivary MVs. Several members of different protein families were identified, including annexin, keratin, actin, immunoglobulin and S100. This study showed that although there was an overlap with the proteins from human saliva and salivary exosomes, salivary MVs contained their own unique proteins. These results will poise human salivary MVs as a non-invasive tool for the early detection of different diseases.
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PMID:Proteomic analysis of microvesicles in human saliva by gel electrophoresis with liquid chromatography-mass spectrometry. 2244 74

Studies on hereditary pancreatitis have provided evidence in favor of central role for trypsin activity in the disease. Identification of genetic variants of trypsinogen linked the protease to the onset of pancreatitis, and biochemical characterization proposed an enzymatic gain of function as the initiating mechanism. Mutations of serine protease inhibitor Kazal type 1 gene (SPINK1) are shown to be associated with hereditary pancreatitis. We previously reported that Spink3 (a mouse homolog gene of human SPINK1) deficient mice showed excessive autophagy, followed by inappropriate trypsinogen activation in the exocrine pancreas. These data indicate that the role of SPINK1/Spink3 is not only trypsin inhibitor, but also negative regulator of autophagy. On the other hand, recent studies showed that high levels of SPINK1 protein detected in a serum or urine were associated with adverse outcome in various cancer types. It has been suggested that expression of SPINK1 and trypsin is balanced in normal tissue, but this balance could be disrupted during tumor progression. Based on the structural similarity between SPINK1 and epidermal growth factor (EGF), we showed that SPINK1 protein binds and activates EGF receptor, thus acting as a growth factor on tumor cell lines. In this review, we summarize the old and new roles of SPINK1/Spink3 in trypsin inhibition, autophagy, and cancer cell growth. These new functions of SPINK1/Spink3 may be related to the development of chronic pancreatitis.
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PMID:Role of Intrapancreatic SPINK1/Spink3 Expression in the Development of Pancreatitis. 2258 7

Doxazolidine (doxaz) is a new anthracycline anticancer agent. While structurally similar to doxorubicin (dox), doxaz acts via a distinct mechanism to selectively enhance anticancer activity over cardiotoxicity, the most significant clinical impediment to successful anthracycline treatment. Here, we describe the synthesis and characterization of a prodrug platform designed for doxaz release mediated by secreted proteolytic activity, a common association with invasiveness and poor prognosis in cancer patients. GaFK-Doxaz is hydrolyzable by the proteases plasmin and cathepsin B, both strongly linked with cancer progression, as well as trypsin. We demonstrate that activation of GaFK-Doxaz releases highly potent doxaz that powerfully inhibits the growth of a wide variety of cancer cells (average IC(50) of 8 nM). GaFK-Doxaz is stable in human plasma and is poorly membrane permeable, thereby limiting activation to locally secreted proteolytic activity and reducing the likelihood of severe side effects.
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PMID:Synthesis and biological characterization of protease-activated prodrugs of doxazolidine. 2274 60


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