Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0596263 (carcinogenesis)
 64,820 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The dermatotoxicity of arsenic is well established and epidemiological studies identify an increased incidence of keratinocytic tumors (basal cell and squamous cell carcinoma) associated with arsenic exposure. Little is known about the underlying mechanisms of arsenic-mediated skin carcinogenesis, but activation of mitogen-activated protein (MAP) kinases and subsequent regulation of downstream target genes may contribute to tumor promotion and progression. In this study, we investigated activation of the extracellular signal regulated kinase (ERK) and the stress-associated kinase p38 by arsenite in HaCat cells, a spontaneously immortalized human keratinocyte cell line. Arsenite concentrations > or =100 microM stimulate rapid activation of p38 and ERK MAP kinases. However, upon extended exposure (24 h), persistent stimulation of p38 and ERK MAP kinases was detected at low micromolar concentrations of arsenite. Although ERK and p38 were activated with similar time and concentration dependence, the mechanism of activation differed for these two MAP kinases. ERK activation by arsenite was fully dependent on the catalytic activity of the epidermal growth factor (EGF) receptor and partially dependent on Src-family kinase activity. In contrast, p38 activation was independent of EGF receptor or Src-family kinase activity. Arsenite-stimulated MAP kinase signal transduction resulted in increased production of matrix metalloproteinase (MMP)-9, an AP-1 regulated gene product. MMP-9 induction by arsenite was prevented when EGF receptor or MAP kinase signaling was inhibited. These studies indicate that EGF receptor activation is a component of arsenite-mediated signal transduction and gene expression in keratinocytes and that low micromolar concentrations of arsenite stimulate key signaling pathways upon extended exposure. Stimulation of MAP kinase cascades by arsenic and subsequent regulation of genes including c-fos, c-jun, and the matrix degrading proteases may play an important role in arsenic-induced skin carcinogenesis.
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PMID:Roles of mitogen activated protein kinases and EGF receptor in arsenite-stimulated matrix metalloproteinase-9 production. 1550 54

Ultraviolet (UV) irradiation is the primary environmental insult responsible for the development of most common skin cancers. To better understand the multiple molecular events that contribute to the development of UV-induced skin cancer, in a first study, serial analysis of gene expression (SAGE) was used to compare the global gene expression profiles of normal SKH-1 mice epidermis with that of UV-induced squamous cell carcinomas (SCCs) from SKH-1 mice. More than 200 genes were found to be differentially expressed in SCCs compared to normal skin (P < 0.0005 level of significance). As expected, genes related to epidermal proliferation and differentiation were deregulated in SCCs relative to normal skin. However, various novel genes, not previously associated with skin carcinogenesis, were also identified as deregulated in SCCs. Northern blot analyses on various selected genes validated the SAGE findings: caspase-14 (reduced 8.5-fold in SCCs); cathepsins D and S (reduced 3-fold and increased 11.3-fold, respectively, in SCCs); decorin, glutathione S-transferase omega-1, hypoxia-inducible factor 1 alpha, insulin-like growth factor binding protein-7, and matrix metalloproteinase-13 (increased 18-, 12-, 12-, 18.3-, and 11-folds, respectively, in SCCs). Chemokine (C-C motif), ligand 27 (CCL27), which was found downregulated 12.7-fold in SCCs by SAGE, was also observed to be strongly downregulated 6-24 h after a single and multiple UV treatments. In a second independent study we compared the expression profile of UV-irradiated versus sham-treated SKH-1 epidermis. Interestingly, numerous genes determined to be deregulated 8 h after a single UV dose were also deregulated in SCCs. For instance, genes whose expression was upregulated both after acute UV-treated skin and SCCs included keratins 6 and 16, small proline-rich proteins, and S100 calcium binding protein A9. Studies like those described here do not only provide insights into genes and pathways involved in skin carcinogenesis but also allow us to identify early UV irradiation deregulated surrogate biomarkers of potential use in chemoprevention studies.
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PMID:SAGE profiling of UV-induced mouse skin squamous cell carcinomas, comparison with acute UV irradiation effects. 1554 21

Nearly a decade has passed since the hypothesis that the insulin-like growth factor (IGF) signalling cascade is involved in prostate carcinogenesis. Recent research has outlined the association of circulating IGF-1 and prostate cancer risk, and studies have elucidated the implication of the IGF network in the early stages of prostate carcinogenesis. Moreover, it has been suggested that IGF-1 induces ligand-independent activation of the androgen receptor and enhances the expression of matrix metalloproteinase-2 and urokinase plasminogen activator. Furthermore, progression to androgen independence has been linked to deregulation of the IGF-1-IGF-1-receptor axis. Here, we report on updated studies that contribute to the unravelling of the IGF 'circuitry' in prostate cancer cells, with the anticipation that relevant pharmacological 'rewiring' might offer novel therapeutic regimens.
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PMID:Novel insights into the implication of the IGF-1 network in prostate cancer. 1569 66

1alpha,25-Dihydroxyvitamin D(3) (1alpha,25-D(3)) has potent antiproliferative and anti-invasive properties in vitro in cancer cells. However, its calcemic effect in vivo limits its therapeutic applications. Here, we report the efficacy of 22-oxa-1alpha,25-dihydroxyvitamin D(3) (22-oxa-1alpha,25-D(3)), a low calcemic analog of vitamin D, against the development of metastatic lung carcinoma after an intravenous injection of green fluorescent protein-transfected Lewis lung carcinoma (LLC-GFP) cells in C57BL/6 mice. The mice injected with tumor cells were implanted simultaneously with osmotic minipumps containing either 1alpha,25-D(3), 22-oxa-1alpha,25-D(3) or vehicle. The 1alpha,25-D(3) treatment group had been hypercalcemic, but the 22-oxa-1alpha,25-D(3) and vehicle treatment groups remained normocalcemic for the duration of the experiment. The total number of lung metastases, lung weight and the expression of GFP mRNA in the lung were markedly decreased in 1alpha,25-D(3) and 22-oxa-1alpha,25-D(3)-treated mice. In the in vitro experiment, 1alpha,25-D(3) and 22-oxa-1alpha,25-D(3) reduced the expression of matrix metalloproteinase (MMP)-2, MMP-9, vascular endothelial growth factor and parathyroid hormone-related protein in LLC-GFP cells. Furthermore, in the angiogenesis assay, the number of tumor cells or basic fibroblast growth factor-induced angiogenesis was reduced in 1alpha,25-D(3) and 22-oxa-1alpha,25-D(3)-treated mice. Moreover, using a new experimental model of vitamin D receptor (VDR) null mutant (VDR(-/-)) mice with corrected hypocalcemia and hypervitaminosis D, we examine the anti-cancer effect of 22-oxa-1alpha,25-D(3) without other functions induced by 22-oxa-1alpha,25-D(3) in the host. In the VDR(-/-) mice, 22-oxa-1alpha,25-D(3) directly inhibited the metastatic activity of LLC-GFP cells in a dose-dependent manner without exerting a direct influence on the calcemic activity or other actions regulated by 22-oxa-1alpha,25-D(3) in the host. These results indicate that the inhibition of metastasis and angiogenesis-inducing activity in cancer cells seemed to be a major mechanism responsible for the anti-cancer effects of 22-oxa-1alpha,25-D(3). Our findings show that 22-oxa-1alpha,25-D(3) is beneficial for the prevention of metastasis in lung carcinoma.
Carcinogenesis 2005 Jun
PMID:22-Oxa-1alpha,25-dihydroxyvitamin D3 inhibits metastasis and angiogenesis in lung cancer. 1571 53

Expression of cyclooxygenase-2 (COX-2) and matrix metalloproteinase-2 (MMP-2) associates with reduced survival in human breast cancer. COX-2 may be directly involved with mammary carcinogenesis, since expression of COX-2 is sufficient for formation of breast tumors in transgenic mice, and COX-2 selective inhibitors can suppress tumorigenesis in rodent models of breast cancer. MMP-2 is an extracellular matrix degrading proteolytic enzyme that bas been linked to invasion and metastasis. A direct link between COX-2 and MMP-2 may exist, since inhibition of COX-2 activity can result in reduction of MMP-2 expression and activity. In this study we analyzed protein expression of COX-2 and MMP-2 in tissue array specimens of 278 invasive breast cancers by immunohistochemistry. Immunopositivity of these two markers was correlated with each other and with various clinicopathological parameters including survival. We found high COX-2 expression in 30% and high MMP-2 expression in 83% of the breast cancer specimens, and there was a positive association between the expression of these two factors (p = 0.003). It was especially evident that whenever COX-2 expression was high, MMP-2 expression was almost invariably high (95%). Furthermore, high expression of either COX-2 or MMP-2 associated with decreased disease specific survival when compared with the COX-2 or MPP-2 low group (p = 0.026 and p = 0.021, respectively). Taken together, our results indicate that expression of COX-2 protein is associated with expression of MMP-2 protein in human breast cancer and that both COX-2 and MMP-2 are markers of poor prognosis in breast cancer.
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PMID:Association of cyclooxygenase-2 and matrix metalloproteinase-2 expression in human breast cancer. 1575 18

Elevated expression of membrane type-1 matrix metalloproteinase (MT1-MMP) is closely associated with malignancies. There is a consensus among scientists that cell surface-associated MT1-MMP is a key player in pericellular proteolytic events. Now we have identified an intracellular, hitherto unknown, function of MT1-MMP. We demonstrated that MT1-MMP is trafficked along the tubulin cytoskeleton. A fraction of cellular MT1-MMP accumulates in the centrosomal compartment. MT1-MMP targets an integral centrosomal protein, pericentrin. Pericentrin is known to be essential to the normal functioning of centrosomes and to mitotic spindle formation. Expression of MT1-MMP stimulates mitotic spindle aberrations and aneuploidy in non-malignant cells. Volumes of data indicate that chromosome instability is an early event of carcinogenesis. In agreement, the presence of MT1-MMP activity correlates with degraded pericentrin in tumor biopsies, whereas normal tissues exhibit intact pericentrin. We believe that our data show a novel proteolytic pathway to chromatin instability and elucidate the close association of MT1-MMP with malignant transformation.
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PMID:Membrane type-1 matrix metalloproteinase (MT1-MMP) exhibits an important intracellular cleavage function and causes chromosome instability. 1587 69

An A to G transition at the 181 base pair position upstream of the transcription initiation site of the matrix metalloproteinase-7 (MMP-7) gene (-181A/G) may modify the development and progression of some diseases via influencing the transcription activity of the promoter. To assess the effects of the functional single nucleotide polymorphism on cancer susceptibility and progression, the MMP-7 -181A/G genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism analysis among 258 patients with esophageal squamous cell carcinoma (ESCC), 201 patients with gastric cardiac carcinoma (GCA), 243 patients with non-small cell lung carcinoma (NSCLC) and 350 healthy individuals without cancer. The result showed that the frequency of the -181G allele in ESCC, GCA and NSCLC patients was significantly higher than that in healthy controls (P = 0.019, 0.023 and 0.004, respectively). Compared with the A/A genotype, genotypes with the -181G allele (A/G + G/G) significantly increased susceptibility to all three tumors, with adjusted odds ratio of 1.83 (95% CI = 1.12-2.99) for ESCC, 1.96 (95% CI = 1.17-3.29) for GCA and 2.00 (95% CI = 1.23-3.24) for NSCLC. Stratification analysis showed that smoking did not significantly influence the association between the MMP-7-181A/G and GCA or NSCLC, while the -181G allele only significantly increased susceptibility to ESCC among smokers. In addition, association between the -181G allele and susceptibility to ESCC and GCA showed significance only among individuals with family history of upper gastrointestinal cancer. The correlation of the MMP-7-181A/G polymorphism with potential of lymphatic metastasis was not observed in all three tumors. The study suggested that, the MMP-7-181A/G polymorphism might be a candidate marker for predicting individuals who are at higher risk to certain tumors but might not be used to predict potential of lymphatic metastasis in ESCC, GCA and NSCLC.
Carcinogenesis 2005 Oct
PMID:The functional polymorphism in the matrix metalloproteinase-7 promoter increases susceptibility to esophageal squamous cell carcinoma, gastric cardiac adenocarcinoma and non-small cell lung carcinoma. 1593 31

A high dietary intake of cruciferous vegetables has been associated with a reduction in numerous human pathologies particularly cancer. In the current study, we examined the inhibitory effects of broccoli (Brassica oleracea var. italica) and watercress (Rorripa nasturtium aquaticum) extracts on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced cancer cell invasion and matrix metalloproteinase-9 activity using human MDA-MB-231 breast cancer cells. Aberrant overexpression of matrix metalloproteinases, including metalloproteinase-9, is associated with increased invasive potential in cancer cell lines. Our results demonstrate that extracts of broccoli and Rorripa suppressed TPA-induced MMP-9 activity and invasiveness in a concentration dependent manner as determined by zymographic analysis. Furthermore, fractionation of individual extracts followed by liquid chromatography mass spectroscopy analysis (LC-MS) revealed that the inhibitory effects of each vegetable were associated with the presence of 4-methysulfinylbutyl (sulforaphane) and 7-methylsulphinylheptyl isothiocyanates. Taken together, our data indicate that isothiocyanates derived form broccoli and Rorripa inhibit metalloproteinase 9 activities and also suppress the invasive potential of human MDA-MB-231 breast cancer cells in vitro. The inhibitory effects observed in the current study may contribute to the suppression of carcinogenesis by diets high in cruciferous vegetables.
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PMID:Broccoli and watercress suppress matrix metalloproteinase-9 activity and invasiveness of human MDA-MB-231 breast cancer cells. 1595 25

Inhibition of invasion and metastasis has become a new approach for treatment of advanced prostate cancer in which secondary hormone therapy has failed. Accumulating evidence indicates that 1alpha,25-dihydroxyvitamin D3 (1,25-VD) suppresses prostate cancer progression by inhibition of tumor growth and metastasis. However, the detailed mechanisms underlying these effects remain to be determined. Here, we used the in vitro cell invasion assay to demonstrate that 1,25-VD inhibits the invasive ability of human prostate cancer cell lines, LNCaP, PC-3 and DU 145. Three major groups of proteases, the matrix metalloproteinases (MMPs), the plasminogen activators (PAs) and the cathepsins (CPs), that are involved in tumor invasion were then examined for changes in activity and expression after 1,25-VD treatment. We found that 1,25-VD decreased MMP-9 and CPs, but not PAs activities, while it increased the activity of their counterparts, tissue inhibitors of metalloproteinase-1 (TIMP-1) and cathepsin inhibitors. Mechanistic studies showed that 1,25-VD did not suppress MMP-9 expression at the transcriptional level, but reduced its mRNA stability. In addition, 1,25-VD increased AP-1 complexes binding to TIMP-1 promoter, which contributed to the enhancement of TIMP-1 activity, and thus resulted in inhibition of MMP activity and tumor invasion. These findings support the idea that vitamin D-based therapies might be beneficial in the management of advanced prostate cancer, especially among patients who have higher MMP-9 and CPs activities.
Carcinogenesis 2006 Jan
PMID:1alpha,25-dihydroxyvitamin D3 inhibits prostate cancer cell invasion via modulation of selective proteases. 1598 15

MT1-MMP (membrane type 1 matrix metalloproteinase, or MMP-14) is a key enzyme in molecular carcinogenesis, tumour-cell growth, invasion and angiogenesis. Novel and potent MMP inhibitors with a mercaptosulphide zinc-binding functionality have been designed and synthesized, and tested against human MT1-MMP and other MMPs. Binding to the MT1-MMP active site was verified by the competitive-inhibition mechanism and stereochemical requirements. MT1-MMP preferred deep P1' substituents, such as homophenylalanine instead of phenylalanine. Novel inhibitors with a non-prime phthalimido substituent had K(i) values in the low-nanomolar range; the most potent of these inhibitors was tested and found to be stable against air-oxidation in calf serum for at least 2 days. To illustrate the molecular interactions of the inhibitor-enzyme complex, theoretical docking of the inhibitors into the active site of MT1-MMP and molecular minimization of the complex were performed. In addition to maintaining the substrate-specificity pocket (S1' site) van der Waals interactions, the P1' position side chain may be critical for the peptide-backbone hydrogen-bonding network. To test the inhibition of cell-mediated substrate cleavage, two human cancer-cell culture models were used. Two of the most potent inhibitors tested reached the target enzyme and effectively inhibited activation of proMMP-2 by endogenous MT1-MMP produced by HT1080 human fibrosarcoma cells, and blocked fibronectin degradation by prostate cancer LNCaP cells stably transfected with MT1-MMP. These results provide a model for mercaptosulphide inhibitor binding to MT1-MMP that may aid in the design of more potent and selective inhibitors for MT1-MMP.
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PMID:Inhibition of enzyme activity of and cell-mediated substrate cleavage by membrane type 1 matrix metalloproteinase by newly developed mercaptosulphide inhibitors. 1602 29


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