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)

The effect on tumor progression produced by the injection of VCN-treated tumor cells in dogs with spontaneous mammary tumors was investigated. Untreated dogs of different races and different ages with at least two palpable spontaneous mammary tumors were selected. One of the tumors was left in the animal for further clinical examination whereas the other tumor(s) was (were) excised for preparation of a single-cell suspension by mechanical disintegration and enzymatic digestion with collagenase and trypsin. (1) In the first group, each animal was infected with 2 times 10-7 similarly prepared autologous, mitomycin-treated tumor cells; in 8 out of 12 dogs of this group the tumors progressed while so far 1 dog has died of metastasis. (2) In the second group, each animal received the same number of 2 times 10-7 tumor cells, which were mitomycin- and VCN-treated: 13 out of 15 dogs had a significant regression of their tumors to less than 10% of the original volume; in 1 dog the tumor remained unchanged and in 1 dog it progressed. (3) In the third group, 8 dogs received 1 times 10-8 mitomycin- and VCN-treated tumor cells: the application of this cell dose resulted in an accelerated tumor progression in all 8 dogs, 3 of which have already died of metastasis. The significance of these findings, with respect to potentiation and abrogation of the immunological response and with regard to immunotherapy in man, is discussed.
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PMID:Regression of spontaneous mammary tumors in dogs after injection of neuraminidase-treated tumor cells. 114 Aug 60

NIH-3T3 cells are non-tumorigenic when injected into athymic mice. If these cells are mixed with an extract of basement-membrane proteins (matrigel) and injected s.c., they form locally invasive and highly vascularized tumors. Cells cultured from the NIH-3T3-matrigel-induced tumors showed a transformed phenotype and lacked contact inhibition. When cultured in a gel of matrigel, they proliferated and formed branched and invasive colonies. In contrast, the parental NIH-3T3 cells cultured on matrigel remained as cell aggregates and were not invasive. I.V. injections of the tumor-derived NIH-3T3 cells produced many colonies on the surface of the lungs, whereas the parental NIH-3T3 cells were not metastatic. Zymographic analysis of the conditioned media obtained from both the tumor-derived and parental NIH-3T3 cells demonstrated higher amounts of the 72-kDa gelatinase (type-IV collagenase) enzyme in the tumor-derived cells. Also, tumor-derived NIH-3T3 cells, but not parental NIH-3T3 cells, secreted the 92-kDa type-IV collagenase. These studies suggest that the interaction of pre-malignant NIH-3T3 cells with extracellular matrix components may contribute to the process of tumor progression.
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PMID:Malignant transformation of NIH-3T3 cells after subcutaneous co-injection with a reconstituted basement membrane (matrigel). 131 8

Although the incidence of, and deaths due to, malignant melanoma are rising at a rapid rate, few experimental models mimic the highly metastatic properties associated with the pathogenesis of the human disease, making study of the disease difficult. Thus, new human models are required to understand melanoma biology, especially its metastatic properties. Here we describe C8161, a highly invasive and spontaneously metastatic human melanoma cell line, which grows progressively in the subcutis of athymic nude mice with an average doubling time of approximately 6 days. By the time the tumor reaches a diameter of 1 cm, amelanotic metastases in lymph nodes, skin, peritoneal wall, spleen and lungs have formed. By comparing C8161 to variants from other well-characterized human malignant melanomas (A375 and MeWo) with differing metastatic traits, properties presumed to be involved in metastatic propensity were examined. C8161 showed a 2- to 14-fold higher ability to invade reconstituted basement membrane barriers in the MICS and correspondingly high type-IV collagenase mRNA levels and collagenolytic activity, as compared with other melanoma cell lines. Likewise, differential adhesion to immobilized RBM or HUVEC monolayers was observed, but did not correlate to rank orders of malignant properties. Recently, a correlation between surface expression of ICAM-1 and secondary tumor formation by human melanomas has been described in several laboratories. Basal levels of ICAM-1 on C8161, A375 and MeWo human melanomas were compared, but no correlation with metastatic potential was noted. Proto-oncogene expression in C8161 cells was compared with A375P and A375M variants using Northern blot analysis. c-myc expression was 6-fold greater than both A375 variants; c-fos expression was 3.4-fold less than A375P and 1.7-fold less than A375M; c-jun in C8161 cells was 2.5-fold and 2.1-fold greater than expression in A375P and A375M, respectively. Because C8161 is so highly malignant, amenable to experimental manipulation, and its behavior in nude mice mimics the clinical course of malignant melanoma, this cell line will prove valuable for studying properties associated with human melanoma tumor progression.
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PMID:Characterization of a highly invasive and spontaneously metastatic human malignant melanoma cell line. 167 Oct 30

Recent studies of murine tumor models and certain human tumor cell lines have provided evidence for intratumor heterogeneity in expression of extracellular matrix receptors and in the elaboration of matrix-degrading enzymes. However, little is known about possible intratumoral heterogeneity in the production of matrix macromolecules. We have, therefore, examined the biosynthesis and secretion of matrix proteins by cells derived from a polyclonal human cell line (JH-17) established from a large cell undifferentiated carcinoma of the lung. For the present studies, we focused on the production of collagens and structural glycoproteins by two phenotypically different aneuploid clones, designated C13 and C22. These clones were distinctive in their inability to grow in soft agar or to form tumors in nude mice and had identical DNA contents. Tumor cells were labeled with [3H]proline and the newly synthesized proteins accumulating in the culture medium were identified using biochemical and immunologic techniques. Clone C13 secreted at least three genetically distinct collagens, including type V procollagen (PC), type IV procollagen, and a type VIII-like collagen. By contrast, the clone C22 synthesized fibronectin, and a single bacterial collagenase-sensitive and pepsin-resistant component consistent with type I trimer. These studies emphasize the potential diversity of matrix proteins synthesized by neoplastic cells and suggest that there is intratumoral heterogeneity in matrix protein biosynthesis in vivo. These studies further suggest that tumor-derived matrix may be altered during tumor progression or cell selection in vivo.
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PMID:Heterogeneity in the production of collagens and fibronectin by morphologically distinct clones of a human tumor cell line: evidence for intratumoral diversity in matrix protein biosynthesis. 282 40

Of five autonomous sublines established independently from the transplantable hormone-dependent mouse mammary tumor, TPDMT-4, three but not two acquired metastatic potential. In in vitro culture using collagen gels, actinonin, an antibiotic protease inhibitor exerted a stronger growth-inhibiting effect on the metastatic than on the parent and non-metastatic tumors. Zymographic analysis demonstrated the active forms of gelatinases in the metastatic but not in the non-metastatic sublines and the complete inhibition of the enzyme activities by actinonin. Gelatinases/type IV collagenases might play an important role in tumor progression towards metastatic phenotype and actinonin may suppress tumor growth through inhibiting collagenase.
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PMID:Effects of an antibiotic protease inhibitor, actinonin on the growth within collagen gels of non-metastatic and metastatic mouse mammary tumors of the same origin. 763 45

The expression of MMP-7 (pump-1) gene was examined in 10 cases of colorectal cancer by utilizing RT-PCR. In 9 out of 10 cases, MMP-7 mRNA was detected in cancerous tissue, whereas none was detected in adjacent normal colon tissue. However, this message was detected in only 1 out of 6 colon-cancer cell lines. In colonic mucosa from 3 patients with ulcerative colitis it was not detected. The expression of MMP-2 (72-kDa type-IV collagenase) mRNA was also investigated in the same tissue samples, and was detected in all samples, including cancerous and non-cancerous tissue. Our data suggest that MMP-7 is expressed in a tumor-associated manner in colorectal cancers and may play a role in tumor progression.
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PMID:Expression of MMP-7(PUMP-1) mRNA in human colorectal cancers. 851 52

Matrix proteases and the transcription factor c-Ets-1, which regulates in vitro stromelysin 1, collagenase 1, and urokinase type plasminogen activator gene promoters, are frequently expressed in invasive carcinomas. Using in situ hybridization and immunohistochemistry, we analyzed collagenase 1, stromelysins 1 and 3, matrilysin, urokinase type plasminogen activator, and c-Ets-1 gene expression on serial frozen sections of 39 intraepithelial bronchial lesions, including areas of hyperplasia, metaplasia, dysplasia, carcinoma in situ, and corresponding lung carcinomas in 13 patients. In intraepithelial lesions, expression of all matrix proteases was detected in epithelial cells. Conversely, in microinvasive or invasive lesions, a fibroblastic expression was observed. Collagenase 1 and matrilysin were expressed seldomly in intraepithelial lesions and frequently in carcinomas (p = 0.0016 and p < 0.0001, respectively). Stromelysin 1 was expressed inconsistently in 31% of intraepithelial lesions of all grades and in 50% of carcinomas. Stromelysin 3 and urokinase type plasminogen activator were expressed only, but frequently, in preinvasive lesions (dysplasia, carcinoma in situ) and in carcinomas. The expression of stromelysin 3 in fibroblasts started with dysplasia and carcinoma in situ, but was more frequent in invasive than preinvasive lesions (p = 0.0012). c-Ets-1 was more often expressed in carcinomas than in intraepithelial lesions (p < 0.0001) and was always expressed in fibroblasts. Comparing preinvasive lesions adjacent to or at a distance from squamous lung carcinoma, stromelysin 3 epithelial expression was more frequent in preinvasive lesions adjacent to invasive foci than in others (p = 0.036). We conclude that (a) both epithelial expression of matrix proteases in intraepithelial bronchial lesions and their stromal expression in microinvasive and invasive lesions suggest their role in lung tumor development; (b) c-Ets-1 does not act as a transcriptional activator for matrix proteases genes in preinvasion, although it might regulate collagenase 1 gene during lung tumor progression; and (c) matrix proteases might offer new therapeutic targets for chemoprevention of lung cancer.
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PMID:Changes in the expression of matrix proteases and of the transcription factor c-Ets-1 during progression of precancerous bronchial lesions. 868 34

Tumor progression to the stage of metastasis may result in part from the selection of certain primary tumor cell clones which are phenotypically competent for survival, invasion, and growth at secondary sites. Selection for traits such as loss of growth inhibitory responses, acquisition of increased adhesiveness, increased local immunosuppression, and enhanced motility and collagenase activities likely contribute to cancer progression and may be regulated through the action of growth factors. The transforming growth factors (TGF-beta) family of growth factors has often been associated with these traits and tumor progression; therefore, elimination or subversion of TGF-beta-responsive pathways should be considered as a mechanistic framework for metastatic events. In this report, we have compared growth and extracellular matrix responses to TGF-beta in six metastatic and six primary tumor-derived cell lines in a mouse model of prostate cancer. We have found that tumor cell lines derived from focal pulmonary metastasis secreted relatively greater quantities of total TGF-betas, lost most or all TGF-beta1 growth inhibition, but responded to TGF-beta1 through induction of the type IV collagenase matrix metalloproteinase-9, whereas cell lines derived from tumors which proliferated at the primary site retained the growth inhibition but lacked collagenase activity. Synthesis of another extracellular matrix protein, plasminogen activator inhibitor 1, was stimulated by TGF-beta1 in both primary as well as metastatic tumors. These results suggest that acquisition of differential responses to the TGF-beta family could result in phenotypic traits which facilitate tumor metastasis from certain primary site clones.
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PMID:Transforming growth factor beta1 stimulates contrasting responses in metastatic versus primary mouse prostate cancer-derived cell lines in vitro. 876 34

Matrix metalloproteinases (MMPs) are expressed in normal remodeling tissues in a generally tissue-restricted pattern. Transcripts for stromelysin-1 and collagenase are expressed primarily in stromal fibroblasts, whereas transcripts for matrilysin are expressed primarily in glandular epithelial cells. These expression patterns are maintained at carcinoma tumor sites until the late stages of tumor progression at which point many epithelially-derived tumors begin to express stromal fibroblast MMPs. Coincidentally, late stage carcinomas take on other characteristics of stromal fibroblasts, indicating that these tumor cells have "transdifferentiated', that is, they have begun to exhibit characteristics of cells from a separate developmental lineage. Despite their distinct expression patterns, many of the promoters for MMP genes show the same general arrangement of the nuclear proto-oncoprotein-binding sites, AP-1 and PEA3. However, the specific interaction between these cis-elements and different combinations of Fos, Jun, and Ets proteins which recognize these sites may be important in controlling both the positive and negative regulation involved in the tissue-restricted pattern of MMP expression in normal and neoplastic tissues.
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PMID:Mechanisms controlling the transcription of matrix metalloproteinase genes in normal and neoplastic cells. 879 95

Epithelial properties of thyrocytes are difficult to maintain in conventional cell culture systems. We used bicameral chambers (Transwell) in attempts to establish a functional epithelium of thyrocytes of human origin. Thyroid follicle segments were isolated by collagenase digestion of paradenomatous tissue obtained at surgery for follicular adenoma and of tissue from glands with Graves' disease. After careful separation from connective tissue and single cells by centrifugation, the follicles were plated at high density on the collagen-coated filter of the chambers and cultured in Eagle's essential medium (EMEM) containing 10% fetal calf serum (FCS) or Coon's modified Hams medium enriched with five or six factors (5H, 6H); the latter media contained 5% FCS without (5H) or with (6H) thyrotropin (TSH). The follicles were converted into a confluent cell layer, which had similar DNA content irrespective of type of medium, after 4-6 days. Cells grown in EMEM or 5H established a transepithelial electrical resistance (R) of 200-500 omega.cm2 and was impermeable to [3H]inulin, indicating the formation of epithelial junctions. Addition of 6H to confluent cells initially cultured in EMEM or 5H caused a further increase of R, maximally to 1500 omega.cm2, along with a rise of the transepithelial potential difference; 6H promoted the monolayer formation of cells, increased the number of apical microvilli and reinforced the junctional distribution of actin, cadherin and ZO-1; 6H also enhanced the polarized secretion of [3H]leucine-labeled thyroglobulin into the apical medium. Cells from Graves' thyroid tissue established an epithelium on the filter with similar characteristics to that of normal thyrocytes; some platings contained in addition large numbers of HLA-DR positive cells with a dendritic shape. HLA-DR expression was generally absent in EMEM-or 5H-grown thyrocytes, but appeared in limited areas of the cell layer after 6H and was expressed by all epithelial cells after interferon-gamma stimulation for 48 h. We conclude that human thyrocytes form a tight and polarized epithelium when cultured on permeable filters. The polarized structure and function of the cells are positively regulated by TSH. The culture system may be useful in studies addressing the role of the epithelial phenotype (cell polarity and tight barrier) in normal thyroid function as well as in pathological processes in the thyroid, such as autoimmunity, cell transformation and tumor progression.
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PMID:Primary culture of human thyrocytes in Transwell bicameral chamber: thyrotropin promotes polarization and epithelial barrier function. 892 31


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