Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Matrix metalloproteinase activity was assessed in culture fluids of organ-cultured human skin by gelatin zymography. Both the 92-kD gelatinase/type IV collagenase and the 72-kD gelatinase/type IV collagenase were detected. Production of the 92-kD enzyme was substantially increased in the presence of epidermal growth factor (EGF) and hepatocyte growth factor (HGF) as compared to control but not in the presence of insulin-like growth factor-1 (IGF-1) or keratinocyte growth factor (KGF). This is of interest because our recent studies have shown that EGF and HGF induce the epithelial cells to invade the underlying stroma while normal architecture is maintained in the presence of IGF-1 and KGF. Addition of tissue inhibitor of metalloproteinase-2 to the organ culture fluids blocked expression of the active forms of both enzymes and concomitantly blocked invasion. Epidermal keratinocytes, dermal fibroblasts and dermal endothelial cells were grown in monolayer culture and examined for matrix metalloproteinase production. The 92-kD enzyme accounted for most of the gelatinase activity in keratinocyte culture fluids while the 72-kD enzyme accounted for most of the activity in the dermal fibroblast and endothelial cell culture fluids. Increased production of the 92-kD enzyme was seen in keratinocytes upon exposure to the growth factors that induced invasion (EGF and HGF) while the two factors that did not induce invasion (IGF-1 and KGF) were much less effective. Production of the 72-kD enzyme in fibroblasts and endothelial cells was not upregulated by any of the four growth factors. Taken together, these data indicate that matrix metalloproteinase activity is increased in the epithelium under the influence of invasion-inducing growth factors and contributes to invasion.
Invasion Metastasis 1996
PMID:Growth factor-induced epidermal invasion of the dermis in human skin organ culture: expression and role of matrix metalloproteinases. 883 Jul 61

Prostate tumor initiation and progression to malignancy may involve upregulation of the androgen receptor known to stimulate prostate cell proliferation; other etiologic mechanisms may include dysfunction of the apoptotic pathway but also deregulation in signal transduction and control of the cell cycle in prostate tissue; such abnormalities could arise from overexpression or mutations in a number of oncogenes or down-regulation by inactivating mutations, allelic loss, or other epigenetic mechanisms in tumor suppressor genes. The advantages and drawbacks of various delivery systems (retroviral, adenoviral, liposomes) used for human gene therapy are being considered. Several ex vivo and in vivo as well as cell culture studies are suggested for the therapy of the human prostate cancer using transfer and expression of genes that might be implicated in prostate carcinogenesis especially of the tumor suppressor p53. Expression of suicidal genes in prostate cancer cells using prostate-specific promoter and enhancer elements as well as targeting of the androgen receptor or the insulin-like growth factor genes with triplex technology in prostate cancer cells and their metastases, is expected to be of therapeutic value.
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PMID:Gene therapy of prostate cancer: p53, suicidal genes, and other targets. 917 86

We used enzymatic activity and immunochemical quantifications to analyse the expression and secretion of cathepsin D by human breast cancer cell lines of different invasive potentials (MCF-7/6, MCF-7/AZ, MDA-MB-231). This study does not directly prove that cathepsin D or procathepsin D is involved in human breast cancer cell invasion and metastasis but it shows that the proportion of procathepsin D (activity and antigen) secreted by the human breast cancer cell lines tested correlates with their invasive potential. In the estrogen receptor-positive MCF-7 subclones, this proportion is increased by estradiol only in the invasive MCF-7/6 variant. The cell content in procathepsin D is increased by estrogens to a greater extent in MCF-7/6 cells as compared to non-invasive MCF-7/AZ cells. Tamoxifen appears to be an estrogen agonist concerning cathepsin D regulation, whereas ICI 182,780 is a true antagonist. Our results suggest that synthesis and secretion of cathepsin D are regulated at two distinct levels and differentially affected by estrogens. Synthesis only seems to be affected in non-invasive MCF-7/AZ cells, whereas in invasive MCF-7/6 cells, both synthesis and the efficiency of secretion are increased by estrogens. Our results also confirm that the key site of regulation leading to lysosomal enzyme oversecretion is the Golgi apparatus insulin-like growth factor-II/mannose 6-phosphate receptor.
Clin Exp Metastasis 1997 Jul
PMID:Western immunoblotting and enzymatic activity analysis of cathepsin D in human breast cancer cell lines of different invasive potential. Regulation by 17beta-estradiol, tamoxifen and ICI 182,780. 921 23

Toremifene is a chlorinated tamoxifen analogue that is indicated for the treatment of postmenopausal hormone-dependent breast cancer. It competes with estradiol for estrogen receptors and has growth-inhibitory effects on MCF-7 breast cancer cells. At concentrations < 10(-6) mol/L, this growth inhibition can be reversed by estradiol, but at higher concentrations toremifene is cytotoxic. In dimethylbenzanthracene (DMBA)-induced mammary cancer in rats, toremifene has been shown to decrease the number of new tumours and to inhibit the growth of existing tumours. Toremifene causes growth inhibition by suppressing mitosis and inducing apoptosis. The mechanism by which these events occur may involve the induction of transforming growth factor-beta 1 and inhibition of insulin-like growth factor-1 (mecasermin). Toremifene is primarily an antiestrogen, but it has some estrogen agonist properties in postmenopausal women. The latter are reflected by the fall in luteinising hormone and follicle-stimulating hormone levels and the rise in sex hormone-binding globulin levels that are associated with its use in most women. After estrogen priming, toremifene 68mg administered orally has been found to exert a similar antiestrogenic effect on the vaginal epithelium in postmenopausal women as tamoxifen 60mg. The half-life of toremifene in plasma is 5 days, and the drug is > 99% bound to plasma proteins. The main metabolites of toremifene are N-demethyl-toremifene and deaminohydroxy-toremifene. Altered liver, but not kidney, function affects the pharmacokinetics of toremifene. Toremifene 60mg daily is as effective as tamoxifen 20mg daily in the treatment of postmenopausal hormone-dependent breast cancer, producing a response in about 50% of patients. Soft tissue and visceral metastases respond better to toremifene than bone metastases. Most of the adverse effects of toremifene are related to its activity at estrogen receptors and include hot flashes, vaginal discharge and nausea. Although toremifene decreases antithrombin III levels slightly, the incidence of thromboembolic complications is low. Thus far, no carcinogenic effects have been noted in humans, and preclinical data are mostly reassuring. Toremifene has favourable effects on serum lipids, and thus has potential in preventing coronary heart disease. Although toremifene is somewhat more expensive to use than tamoxifen, toremifene is an effective and well tolerated alternative to tamoxifen in the treatment of postmenopausal women with hormone-dependent breast cancer. No formal pharmacoeconomic comparisons of toremifene and tamoxifen have yet been published. Toremifene is potentially safer than tamoxifen in relation to carcinogenic effects and effects on serum lipids.
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PMID:Toremifene in postmenopausal breast cancer. Efficacy, safety and cost. 934 56

The authors have previously shown that the type 1 insulin-like growth factor receptor (IGF-1R) is decreased in the transformation from benign to malignant human prostate epithelial cells in vivo. Further, in a well-described human SV40-T immortalized human epithelial cell system beginning with the immortalized, but rarely tumorigenic P69SV40-T cell line, to the highly tumorigenic and metastatic M12 subline, there is a similar decrease in IGF-1R number from 2.0 x 10(4) receptors per cell to 1.1 x 10(3) receptors per cell. When the IGF-1R was reexpressed in the M12 subline using a retroviral expression vector, M12-LISN, to a receptor number similar to that of the P69SV40-T parental cell line, the authors demonstrated a marked decrease in colony formation in soft agar in the M12-LISN cells vs the M12 control cells (p < or = 0.01), and a decrease in vivo tumor growth and metastases when injected either subcutaneously or an intraprostatic location (p < or = 0.01). This decrease in tumor volume was not because of a decrease in proliferative capacity, but was associated with an increase in apoptosis in baseline cultures and in response to the apoptotic-inducing agents 6-hydroxyurea, retinoic acid, and transforming growth factor beta 1.
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PMID:Type-1 insulin-like growth factor receptor reexpression in the malignant phenotype of SV40-T-immortalized human prostate epithelial cells enhances apoptosis. 944 47

The insulin-like growth factor II is mitogenic for a number of cell types and can inhibit apoptosis. The frequent expression of this gene in human and experimental animal tumors indicates that insulin-like growth factor-2 may play an important role in tumor development. It has also been hypothesized that overexpression of this growth factor may be responsible for the increased incidence of childhood tumors in patients with Beckwith-Wiedemann syndrome. To assess the effects of Igf2 on tumor development we produced six transgenic mouse lines that express the gene under the control of the H19 enhancers. Transgenic expression was initiated in the embryonic period but remained high in several adult tissues, including the mammary gland, lung, and liver. Adult transgenic females from five of the transgenic lines developed often multiple mammary tumors that had the ability to metastasize. Increased incidence of other solid tumors was also noted in older mice. These findings indicate that Igf2 expression increases the probability of malignant transformation and that the mammary gland is at a particularly high risk of tumor development in response to chronic increase in Igf2 gene dosage.
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PMID:Metastasizing mammary carcinomas in H19 enhancers-Igf2 transgenic mice. 957 68

We report a 22-yr-old male patient with chronic hepatitis B and a large, well differentiated hepatoma who developed episodes of symptomatic fasting hypoglycemia, which were caused by paraneoplastic secretion of unprocessed "big" insulin-like growth factor-II. Initially, the patient presented with normal liver function, which deteriorated during the clinical course. Therapeutic attempts to reduce tumor mass failed and the patient subsequently died because of metastases of the hepatoma. The pathophysiology of non-islet cell tumor hypoglycemia, differential diagnosis, and therapeutic options are discussed.
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PMID:Hepatoma with severe non-islet cell tumor hypoglycemia. 964 37

The limited proteolysis of insulin-like growth factor (IGF)-binding protein (IGFBP)-3 is a key event in the regulation of endocrine bioavailability of IGFs. Here, we investigated IGFBP-3 and IGFBP-3 proteolysis in serum from patients with colorectal cancer both before and at different times following surgery. In vivo IGFBP-3 proteolysis, estimated by immunoblot analysis of IGFBP-3 fragments in serum, and in vitro IGFBP-3 protease activity of serum, estimated by a 125I-IGFBP-3 degradation assay, allowed us to identify 2 groups of patients (IGF-M vs. IGF-NM) with respect to their status for mobilizing the IGF system. In IGF-M patients, in vivo and in vitro IGFBP-3 proteolysis were significantly elevated (156% and 181% of the age-matched control pool, respectively) and accompanied by a decrease in intact IGFBP-3 (38% of the control pool). The IGFBP-3 proteolytic processing was further increased in response to surgical ablation of the tumor (mean increase 45-55%), then gradually returned to levels comparable with controls. In contrast, IGF-NM patients exhibited a minimal alteration of in vitro IGFBP-3 protease activity and even an inhibition of in vivo IGFBP-3 proteolysis, whereas intact IGFBP-3 was unaltered when compared with controls. Moreover, this pattern was not further significantly altered in response to the surgical stress. None (0/6) of the IGF-M patients vs. 70% (5/7) of the IGF-NM patients developed a metastatic disease (median duration of follow-up 26 months). Neither elevated amounts of pro-IGF-II nor presence of detectable IGFBP-3 protease inhibitors in the circulation could explain the observed suppression of IGFBP-3 proteolytic processing in IGF-NM patients. These results indicate that inhibition of IGFBP-3 proteolysis and invasive properties of cancer cells are related in colorectal cancer patients.
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PMID:Insulin-like growth factor (IGF)-binding protein-3 (IGFBP-3) proteolysis in patients with colorectal cancer: possible association with the metastatic potential of the tumor. 976 Nov 13

The insulin-like growth factor-1 receptor (IGF-1R) and its possible protective effect on apoptotic cell death in malignant melanoma was analysed in four commercial melanoma cell lines. Inhibition of N-linked glycosylation by tunicamycin, which has previously been shown to block the translocation of IGF-1R to the cell surface, blocked cell growth and/or induced cell death in these cell lines. Treatment with alphaIR-3, an antibody blocking the binding domain of IGF-1R, also resulted in growth arrest and/or apoptosis. We also analysed lymph node metastases of malignant melanoma by Western blotting and immunohistochemistry. All these cases were shown to express IGF-1R at the cell surface. In three cases of lymph node metastases we had access to both tumour specimens and cultured cells. One of these exhibited a substantially higher expression of IGF-1R than the two other cases. The corresponding cell lines showed growth arrest and apoptosis following treatment with alphaIR-3. However, the two cell lines with low expression of IGF-1R were more sensitive in this respect. Furthermore, we demonstrated an inverse correlation between IGF-1R expression and the frequency of apoptotic cells in the tumour specimens. Our data suggest that IGF-1R is crucial for the viability of malignant melanoma cells in vitro as well as in vivo.
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PMID:Expression of the insulin-like growth factor-1 receptor and its anti-apoptotic effect in malignant melanoma: a potential therapeutic target. 983 51

Many of the alterations in the insulin-like growth factor (IGF) axis in prostatic disease have been associated with changes in the insulin-like growth factor binding proteins (IGFBPs), a multigene family of proteins that are thought to mediate the action of IGFs on target tissues. IGFBP-related protein 1 (rP1), also known as IGFBP-7 or mac25, is a recently described member of the IGFBP family, the biological function of which has yet to be completely ascertained. In this study, we analyzed the localization of IGFBP-rP1 in prostate cancer and benign prostate tissues using immunohistochemistry and a polyclonal antibody, T1A12, that is specific for IGFBP-rP1. The most intense staining was observed in nerves, whereas smooth muscle cells in the prostate stained weakly. Lymphocytes were always negative. When normal prostatic secretory epithelium was present, staining was usually absent. The lining secretory epithelium stained positively in 0 of 12 (0%) cases of benign prostatic hyperplasia, 57 of 63 (90.5%) primary adenocarcinomas, and 7 of 7 (100%) prostate cancer metastases. Prostatic intraepithelial neoplasia showed a similar pattern of staining to that observed for the invasive tumors. Analysis of Northern blots showed that none of the prostate cancer cell lines (LNCaP, C4, C4-2, C4-2B4, 9069E3, DU145, and PC3) expressed IGFBP-rP1 mRNA. This lack of expression was confirmed by immunohistochemistry of s.c.-generated tumor xenografts of LNCaP and C4-2 and by immunoblot on serum-free-conditioned media from all prostatic cell lines. In contrast to these results, tumor xenografts generated by direct intraosseous injection of LNCaP or C4-2 to bone marrow space resulted in tumors that stained positively for IGFBP-rP1. Our results show that IGFBP-rP1 is expressed in both in situ and invasive prostate neoplasms, but not typically in normal secretory or BPH epithelium; furthermore, the expression of IGFBP-rP1 can be induced in human prostate cancer cell lines in vivo on interaction with an appropriate host environment.
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PMID:Human prostate cancer expresses the low affinity insulin-like growth factor binding protein IGFBP-rP1. 1038 31


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