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)

Recently we reported that human dermal fibroblasts, or conditioned media obtained from such cells, affect the growth of human melanoma cells as a direct function of tumor progression: melanoma cells obtained from early-stage (metastatically incompetent) primary lesions were growth inhibited, whereas cells obtained from more advanced (metastatically competent) primary lesions, or metastases, were growth stimulated. Ion-exchange and gel-filtration chromatography of fibroblast conditioned medium revealed the inhibitor to be a protein of molecular mass between 20 and 30 kDa and distinct from the stimulator. This is the approximate molecular mass of interleukin 6 (IL-6), a ubiquitous multifunctional cytokine known to affect in particular many kinds of hemopoietic and lymphoid cells. Since this cytokine is known to be made by fibroblasts, we attempted to determine if the human fibroblast-derived growth inhibitor (hFDGI) was identical to IL-6. Neutralizing antibodies specific for IL-6 completely eliminated the inhibitory activity of hFDGI. Moreover, exposure to human recombinant IL-6 was found to inhibit the growth of early-stage melanoma cells obtained from radial growth phase (RGP) or early vertical growth phase (VGP) primary lesions in three of four cases. In contrast, melanoma cells from a number of more advanced VGP primary lesions, or from distant metastases, were completely resistant to this IL-6-mediated growth inhibition. Acquisition of an "IL-6-resistant" phenotype by metastatically competent melanoma cell variants may provide such cells with a proliferative advantage within the dermal mesenchyme (a hallmark of melanoma cells that are malignant), helping them eventually to dominate advanced primary lesions and to establish secondary growths elsewhere.
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PMID:Interleukin 6: a fibroblast-derived growth inhibitor of human melanoma cells from early but not advanced stages of tumor progression. 140 27

A human multiple myeloma (MM) cell line, U-266, has developed the ability to grow independently of exogenous interleukin 6 (IL-6) during long-term cultivation in vitro. The early passage, feeder-cell dependent U-266 cell line (U-266-1970) was compared with the late passage U-266-1984 cell line with respect to response to IL-6, IL-1 beta and tumour necrosis factor alpha and expression of IL-6 and IL-6 receptor (IL-6R) mRNA and protein. The results showed that; (a) only the U-266-1970 cell line was stimulated to growth by IL-6, (b) IL-6 and IL-6R mRNA were expressed in both cell lines, (c) the level of IL-6 mRNA was increased in the U-266-1984 cell line and only this line produced IL-6 and, (d) the level of IL-6R mRNA was highest in the U-266-1984 cell line and the number of IL-6R about ten times higher than in U-266-1970. The growth of the IL-6-producing U-266-1984 cell line was inhibited by 30% by anti-IL-6R antibodies suggesting the possibility that an autocrine IL-6 loop might have developed during the long-term cultivation. In addition to many other phenotypic alterations of the U-266 cell line, having developed as a consequence of tumor progression in vitro, its growth factor requirement seems to have evolved from a dependence on IL-6 as a paracrine growth factor to a capacity for autonomous growth, dependent on autocrine IL-6 stimulation. Whether such a development also may take place in MM clones in vivo remains to be established.
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PMID:Increase in interleukin 6 (IL-6) and IL-6 receptor expression in a human multiple myeloma cell line, U-266, during long-term in vitro culture and the development of a possible autocrine IL-6 loop. 158 93

The growth of solid tumors to a clinically relevant size is dependent upon an adequate blood supply. This is achieved by the process of tumor stroma generation where the formation of new capillaries is a central event. Progressive recruitment of blood vessels to the tumor site and reciprocal support of tumor expansion by the resulting neovasculature are thought to result in a self-perpetuating loop helping to drive the growth of solid tumors. The development of new vasculature also allows an 'evacuation route' for metastatically-competent tumor cells, enabling them to depart from the primary site and colonize initially unaffected organs. Several molecular and cellular mechanisms have been identified by which tumor parenchyma may exert its angiogenic effect on host endothelial cells. As a result of this paracrine influence, tumor-associated endothelial cells acquire an 'immature' phenotype manifested by rapid proliferation, migration, release of proteases and expression of cytokines, endothelial-specific tyrosine kinases (e.g. flk-1, tek and others) as well as numerous other molecular alterations. Consequently a network of structurally and functionally aberrant blood vessels is formed within the tumor mass. There is also evidence that endothelial cells themselves, and likewise other stromal cells, may act reciprocally to alter the behavior of adjacent tumor cells in a paracrine or cell contact mediated fashion. For example, production of interleukin 6(IL-6) by endothelial cells may have a differential effect on human melanoma cells expressing different degrees of aggressiveness. In this manner endothelial derived cytokines could conceivably contribute to tumor progression by suppressing the growth of the less aggressive tumor cells and promoting dominance of their malignant counterparts in 'strategic' perivascular zones. Distinct biological features expressed by tumor-associated vasculature may serve as potential prognostic markers of disease progression as well as novel targets for therapeutic intervention.
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PMID:Consequences of angiogenesis for tumor progression, metastasis and cancer therapy. 753 29

Cell-to-cell interaction between tumors and host inflammatory cells is important for the subsequent cancer progression or regression. We examined the expressions of mRNAs for various proinflammatory cytokines by nine human lung cancer cell lines and the influences of cytokines on their gene expressions. The cytokines used were interleukin 1 beta (IL-1 beta), interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha), granulocyte-macrophage colony stimulating factor (GM-CSF) and monocyte chemotactic and activating factor. Gene expressions of cytokines were measured by Northern blot analysis. Substantial expressions of cytokine genes were detected in several lung cancer cell lines such as RERF-LC-MS, RERF-LC-OK and VMRC-LCD, although the levels of expression of each cytokine varied in different cell lines. Four lung cancer cell lines (RERF-LC-MS, RERF-LC-OK, A549 and YO-88) were used to examine the effects of exogenous cytokines (IL-1 beta, TNF-alpha and GM-CSF) on cytokine gene expressions by the cells. TNF-alpha and IL-1 beta caused significant changes in the levels of mRNA expressions of certain cytokines. Moreover, on stimulation with TNF-alpha, RERF-LC-OK cells produced IL-6 extracellularly. These extensive differences in the levels of gene expressions and productions of cytokines could have profound effects on the interactions between human lung cancer cells and the corresponding host cells.
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PMID:Autonomous expressions of cytokine genes by human lung cancer cells and their paracrine regulation. 814 99

Attempts to grow primary murine plasmacytomas in vitro have, to date, been largely unsuccessful. In this study, we demonstrate that long-term in vitro growth of primary plasmacytomas is accomplished by using feeder layers composed of stromal cells from the initial site of plasmacytomagenesis. The early neoplastic lines established in this manner are dependent on physical contact with the stromal layer, which is mediated in part by CD44, for growth and survival. The stromal cells provide at least two stimuli for the plasma cells, one being interleukin 6 and the second, of unknown nature, resulting from direct physical interaction that cannot be replaced by soluble factors. These plasma cell lines have been passaged for as long as 20 months yet still maintain characteristics associated with primary plasmacytomas as they will grow in vivo only in pristane-primed animals, indicating a continued dependence on the pristane-induced microenvironment characteristic of early-stage tumors. The ability to grow primary plasmacytomas in culture and maintain their "primary" properties provides a model system for detailed analysis of early events in plasma cell tumor progression involving neoplastic cells completely dependent on physical contact with a stromal feeder layer for survival and expansion.
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PMID:In vitro culture of primary plasmacytomas requires stromal cell feeder layers. 844 28

Prediction of survival for patients with metastatic breast cancer is often inaccurate and may be helped by new biological parameters. Tumour growth being angiogenesis-dependent, it has been hypothesised that the assessment of angiogenic factor production might reflect the clinical behaviour of cancer progression. This study was designed to investigate the clinical significance of vascular endothelial growth factor (VEGF) and interleukin 6 (IL-6) in hormone-refractory metastatic breast cancer. Serum and plasma concentrations of VEGF and serum concentration of IL-6 were measured in 87 patients with a fully documented history of metastatic breast cancer using an enzyme-linked immunoassay. All patients had detectable levels of VEGF, whereas 39% patients had detectable serum levels of IL-6. There was a positive correlation between IL-6 levels and the theoretical VEGF load of platelets (P<0.001). The presence of high levels of serum IL-6, but not VEGF, was significantly correlated to a shorter survival. In a multivariate analysis along with clinical prognostic parameters, serum IL-6 was identified as an independent adverse prognostic variable for overall survival (P&<0.001). These results indicate that serum IL-6 levels correlate to poor survival in patients with hormone-refractory metastatic breast cancer. Vascular endothelial growth factor serum and plasma levels are not useful indicators of prognosis for these patients.
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PMID:Prognostic value of serum levels of interleukin 6 and of serum and plasma levels of vascular endothelial growth factor in hormone-refractory metastatic breast cancer patients. 1277 87

We investigated the biologic meaning of tumor-associated macrophages (TAM) in renal cell carcinoma (RCC). The study group comprised of 83 patients with RCC. TAM was isolated by plastic adherence following enzymatic digestion of surgically removed tumor tissues. In some of the patients, monocytes were also isolated from peripheral blood mononuclear cells by plastic adherence. When TAM and monocytes were compared in the same patients, TAM produced interleukin 6 (IL-6), tumor necrosis factor alpha (TNFalpha) and interleukin 1beta (IL-1beta) without lipopolysaccharide (LPS) stimulation, while monocytes hardly produced IL-6, TNFalpha and IL-1beta without LPS stimulation. However, with LPS stimulation, monocytes produced more IL-6, TNFalpha and IL-1beta than TAM. In stage T1 RCC patients, there was a significant positive correlation between TNFalpha production of TAM and tumor size. In order to investigate the effects of TAM on cancer cells, TAM was co-cultured with A498, K562 and in some cases, with short-term established RCC lines for 96 h. As a result, TAM largely enhanced cell proliferation. These results suggested that TAM may play an important role in certain steps of tumor progression.
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PMID:Role of tumor-associated macrophages in renal cell carcinoma. 1453 6

Although numerous studies have implicated vitamin D in preventing prostate cancer, the underlying mechanism(s) remains unclear. Using normal human prostatic epithelial cells, we examined the role of mitogen-activated protein kinase phosphatase 5 (MKP5) in mediating cancer preventive activities of vitamin D. Up-regulation of MKP5 mRNA by 1,25-dihydroxyvitamin-D3 (1,25D) was dependent on the vitamin D receptor. We also identified a putative positive vitamin D response element within the MKP5 promoter that associated with the vitamin D receptor following 1,25D treatment. MKP5 dephosphorylates/inactivates the stress-activated protein kinase p38. Treatment of prostate cells with 1,25D inhibited p38 phosphorylation, and MKP5 small interfering RNA blocked this effect. Activation of p38 and downstream production of interleukin 6 (IL-6) are proinflammatory. Inflammation and IL-6 overexpression have been implicated in the initiation and progression of prostate cancer. 1,25D pretreatment inhibited both UV- and tumor necrosis factor alpha-stimulated IL-6 production in normal cells via p38 inhibition. Consistent with inhibition of p38, 1,25D decreased UV-stimulated IL-6 mRNA stabilization. The ability of 1,25D to up-regulate MKP5 was maintained in primary prostatic adenocarcinoma cells but was absent in metastases-derived prostate cancer cell lines. The inability of 1,25D to regulate MKP5 in the metastasis-derived cancer cells suggests there may be selective pressure to eliminate key tumor suppressor functions of vitamin D during cancer progression. These studies reveal MKP5 as a mediator of p38 inactivation and decreased IL-6 expression by 1,25D in primary prostatic cultures of normal and adenocarcinoma cells, implicating decreased prostatic inflammation as a potential mechanism for prostate cancer prevention by 1,25D.
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PMID:Inhibition of p38 by vitamin D reduces interleukin-6 production in normal prostate cells via mitogen-activated protein kinase phosphatase 5: implications for prostate cancer prevention by vitamin D. 1661 80

Focal adhesion kinase (FAK) is a cytoplasmic protein-tyrosine kinase that promotes cell migration, survival, and gene expression. Here we show that FAK signaling is important for tumor necrosis factor-alpha (TNFalpha)-induced interleukin 6 (IL-6) mRNA and protein expression in breast (4T1), lung (A549), prostate (PC-3), and neural (NB-8) tumor cells by FAK short hairpin RNA knockdown and by comparisons of FAK-null (FAK(-/-)) and FAK(+/+) mouse embryo fibroblasts. FAK promoted TNFalpha-stimulated MAPK activation needed for maximal IL-6 production. FAK was not required for TNFalpha-mediated nuclear factor-kappaB or c-Jun N-terminal kinase activation. TNFalpha-stimulated FAK catalytic activation and IL-6 production were inhibited by FAK N-terminal but not FAK C-terminal domain overexpression. Analysis of FAK(-/-) fibroblasts stably reconstituted with wild type or various FAK point mutants showed that FAK catalytic activity, Tyr-397 phosphorylation, and the Pro-712/713 proline-rich region of FAK were required for TNFalpha-stimulated MAPK activation and IL-6 production. Constitutively activated MAPK kinase-1 (MEK1) expression in FAK(-/-) and A549 FAK short hairpin RNA-expressing cells rescued TNFalpha-stimulated IL-6 production. Inhibition of Src protein-tyrosine kinase activity or mutation of Src phosphorylation sites on FAK (Tyr-861 or Tyr-925) did not affect TNFalpha-stimulated IL-6 expression. Moreover, analyses of Src(-/-), Yes(-/-), and Fyn(-/-) fibroblasts showed that Src expression was inhibitory to TNFalpha-stimulated IL-6 production. These studies provide evidence for a novel Src-independent FAK to MAPK signaling pathway regulating IL-6 expression with potential importance to inflammation and tumor progression.
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PMID:Tumor necrosis factor-alpha stimulates focal adhesion kinase activity required for mitogen-activated kinase-associated interleukin 6 expression. 1743 36

Recent studies have demonstrated that chronic stress promotes tumor growth, angiogenesis, and metastasis. In ovarian cancer, levels of the pro-angiogenic cytokine, interleukin 6 (IL-6), are known to be elevated in individuals experiencing chronic stress, but the mechanism(s) by which this cytokine is regulated and its role in tumor growth remain under investigation. Here we show that stress hormones such as norepinephrine lead to increased expression of IL-6 mRNA and protein levels in ovarian carcinoma cells. Furthermore, we demonstrate that norepinephrine stimulation activates Src tyrosine kinase and this activation is required for increased IL-6 expression. These results demonstrate that stress hormones activate signaling pathways known to be critical in ovarian tumor progression.
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PMID:Stress hormones regulate interleukin-6 expression by human ovarian carcinoma cells through a Src-dependent mechanism. 1771 80


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