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 reported that down-modulation of tissue inhibitor of metalloproteinases (TIMP) by means of antisense RNA converts non-tumorigenic Swiss 3T3 cells into malignant cells capable of forming metastasizing tumors in nude mice [Science 243:947 (1989)]. We now describe changes in the expression of specific genes associated with tumor progression of two lines down-modulated with TIMP, LA1 and LA7. Six independent variant cell lines, generated from different primary tumors produced by LA1 and LA7, lacked (like LA1 and LA7) many characteristics of typical transformed cells. However, their tumorigenicity in nude mice was enhanced; tumors appeared with a shorter lag (1-3 weeks versus 8-10 weeks for the parental clones, LA1 and LA7) and grew very rapidly. Increases, substantial in some cases, in the expression of a cysteine proteinase, cathepsin L, and metalloproteinases homologous to rat transin (stromelysin) and transin-2 were characteristic of these variant clones. The mRNA levels encoding the transformation-associated secreted phosphoprotein (osteopontin) and the calcium-binding protein calcyclin were also augmented. No evidence for gene amplification was found, and we did not detect any change in the mRNA levels of the proto-oncogenes that were examined. These novel cell lines represent a new paradigm for the transformed cell. Our data suggest that a reduction in TIMP secretion enhances the cell's oncogenic capacity by altering the extracellular environment in a way conducive to further changes in gene expression necessary for tumor progression.
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PMID:Increased proteinase expression during tumor progression of cell lines down-modulated for TIMP levels: a new transformation paradigm? [corrected]. 206 53

Transfected ras oncogenes have been shown to induce metastatic properties in some cells. Clarification of the mechanisms by which ras is able to increase the metastatic ability in model systems will improve our understanding of tumor progression to metastasis, even in those cells in which ras activation has not been implicated. Many of the consequences of ras expression also have been detected in cells that have become metastatic in the apparent absence of an altered ras gene, suggesting that there is a set of common changes that can lead to metastasis with multiple signals capable of eliciting these changes. These changes, which have been documented for some ras-transformed cells, include increased expression or activity of various degradative enzymes, including metalloproteinases (type IV collagenases) and cysteine proteinases (cathepsins L and B), as well as decreased expression or activity of their inhibitors (TIMPs and cystatins, respectively). In addition, some metastatic ras-transformed cells have an increased expression of calcyclin, a cytoplasmic calcium-binding protein, and osteopontin, a secreted calcium-binding protein with possible adhesive function. Not all cells, however, respond in the same fashion to a ras oncogene signal. Some cells are resistant to ras-mediated tumor progression to metastasis. Understanding the mechanism by which these cells fail to respond to a specific oncogene signal may provide clues with broader applicability and potential therapeutic relevance. In this review, we summarize some of the studies in which ras has been used as a tool to learn about the molecular requirements for metastasis. We discuss ras-mediated changes in gene expression and how these may contribute to metastatic ability, as well as some possible mechanisms by which ras expression may result in altered expression of other genes. We also consider some cell lines which appear to be resistant to an oncogenic ras signal and possible mechanisms for this nonresponsiveness. These studies are providing insights into the molecular mechanisms of tumor metastasis and the responses of cells to oncogenic signals.
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PMID:Ras-responsive genes and tumor metastasis. 842 May 73

Tumor cells are characterized by uncontrolled growth, invasion to surrounding tissues, and metastatic spread to distant sites. Mortality from cancer is often due to metastasis since surgical removal of tumors can enhance and prolong survival. The integrins constitute a family of transmembrane receptor proteins composed of heterodimeric complexes of noncovalently linked alpha and beta chains. Integrins function in cell-to-cell and cell-to-extracellular matrix (ECM) adhesive interactions and transduce signals from the ECM to the cell interior and vice versa. Hence, the integrins mediate the ECM influence on cell growth and differentiation. Since these properties implicate integrin involvement in cell migration, invasion, intra- and extra-vasation, and platelet interaction, a role for integrins in tumor growth and metastasis is obvious. These findings are underpinned by observations that the integrins are linked to the actin cytoskeleton involving talin, vinculin, and alpha-actinin as intermediaries. Such cytoskeletal changes can be manifested by rounded cell morphology, which is often coincident with tumor transformation via decreased or increased integrin expression patterns. For the various types of cancers, different changes in integrin expression are further associated with tumor growth and metastasis. Tumor progression leading to metastasis appears to involve equipping cancer cells with the appropriate adhesive (integrin) phenotype for interaction with the ECM. Therapies directed at influencing integrin cell expression and function are presently being explored for inhibition of tumor growth, metastasis, and angiogenesis. Such therapeutic strategies include anti-integrin monoclonal antibodies, peptidic inhibitors (cyclic and linear), calcium-binding protein antagonists, proline analogs, apoptosis promotors, and antisense oligonucleotides. Moreover, platelet aggregation induced by tumor cells, which facilitates metastatic spread, can be inhibited by the disintegrins, a family of viper venom-like peptides. Therefore, adhesion molecules from the integrin family and components of angiogenesis might be useful as tumor progression markers for prognostic and for diagnostic purposes. Development of integrin cell expression profiles for individual tumors may have further potential in identifying a cell surface signature for a specific tumor type and/or stage. Thus, recent advances in elucidating the structure, function, ECM binding, and signaling pathways of the integrins have led to new and exciting modalities for cancer therapeutics and diagnoses.
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PMID:Role of integrins in cancer: survey of expression patterns. 1056 36

The mechanism of cell immortalization of human breast epithelial cells leading to neoplastic transformation is not clear. The isolation and characterization of a spontaneously immortalized human breast epithelial cell line, MCF-10F, have provided a valuable tool to identify genes involved in this process. Using the technique of differential display, we have identified seven cDNA bands differentially displayed in the MCF-10F cells when compared with the mortal S130 cells from which MCF-10F was originated. One of these bands was isolated and cloned. Sequence analysis revealed 99% homology to the EF-hand calcium-binding protein S100P (Placental). The clone was overexpressed in the immortal cell line MCF-10F when compared to the mortal counterpart S130 or other primary cultures of human breast epithelial cells. In addition, it was highly expressed in chemically transformed breast epithelial cell lines (BP1E and D3. 1), breast cancer cell line T47D, as well as in three invasive ductal carcinomas when compared to their normal adjacent tissue. The S100P protein was localized by immunohistochemistry, using a monoclonal antibody against the same amino acid sequence of the gene cloned, in ductal hyperplasias, in situ and invasive ductal carcinoma, but not in the normal tissues. We concluded that S100P overexpression is an early event that might play an important role in the immortalization of human breast epithelial cells in vitro and tumor progression in vivo.
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PMID:S100P calcium-binding protein overexpression is associated with immortalization of human breast epithelial cells in vitro and early stages of breast cancer development in vivo. 1063 64

Elevated S100A4 protein expression is associated with metastatic tumor progression and appears to be a strong molecular marker for clinical prognosis. S100A4 is a calcium-binding protein that is known to form homodimers and interacts with several proteins in a calcium-dependent manner. Here we show that S100A4 localizes to lamellipodia structures in a migrating breast cancer-derived cell line and colocalizes with a known S100A4-interacting protein, myosin heavy chain IIA, at the leading edge. We demonstrate that S100A4 mutants that are defective in either their ability to dimerize or in calcium binding are unable to interact with myosin heavy chain IIA. An S100A4 mutant that is deficient for calcium binding retains the ability to form homodimers, suggesting that S100A4 can exist as calcium-free or calcium-bound dimers in vivo. However, a calcium-bound S100A4 monomer only interacts with another calcium-bound monomer and not with an S100A4 mutant that does not bind calcium. Interestingly, despite the calcium dependence for interaction with known protein partners, calcium binding is not necessary for localization to lamellipodia. Both wild type and a mutant that is deficient for calcium binding colocalize with known markers of actively forming leading edges of lamellipodia, Arp3 and neuronal Wiskott-Aldrich syndrome protein. These data suggest that S100A4 localizes to the leading edge in a calcium-independent manner, and identification of the proteins that are involved in localizing S100A4 to the lamellipodial structures may provide novel insight into the mechanism by which S100A4 regulates metastasis.
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PMID:Characterization of the metastasis-associated protein, S100A4. Roles of calcium binding and dimerization in cellular localization and interaction with myosin. 1275 52

Mts1 (S100A4) is a calcium-binding protein of the EF-hand type, belonging to the S100 family of proteins. The mts1/S100A4 gene was originally isolated from tumor cell lines, and the protein is believed to play an important role in tumor progression. More recently, oligomeric, but not dimeric, forms of Mts1 have been shown to have a neuritogenic effect when added extracellularly to hippocampal neurons. Here we show increased neurite outgrowth in two other cell types, dopaminergic and cerebellar neurons, in response to treatment with Mts1 oligomers. Moreover, we demonstrate that Mts1 acts as a neuroprotectant in primary cerebellar, dopaminergic, and hippocampal neurons induced to undergo cell death. Interestingly, the survival of the cerebellar and hippocampal neurons increased as a result of treatment with Mts1 not only in oligomeric form but also--although to a lesser extent--in dimeric form. The inhibition of death in cerebellar neurons by Mts1 was accompanied by an inhibition of DNA fragmentation, but Mts1 did not affect the activity of caspases-3 and -6. In hippocampal neurons, cell death induced by the amyloid-beta peptide (Abeta(25-35)) was characterized by an increase in caspase-3 and -6 activity, but no DNA fragmentation was observed. As in cerebellar neurons, the induced increase in caspase activity in hippocampal neurons was not affected by Mts1.
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PMID:The Mts1/S100A4 protein is a neuroprotectant. 1533 97

Tumour cell invasion and metastasis are the hallmark of malignant neoplasm. S100A4 is a member of small calcium-binding protein family and is involved in the cell proliferation and cancer progression. S100A4 is capable of inducing metastasis in animal models and is associated with aggressive phenotype of human tumours. We previously identified S100A4 as a candidate gene involved in anaplastic thyroid cancer metastasis by microarray analysis. To further determine whether S100A4 overexpression is associated with thyroid tumour invasion and metastasis, in the present study, we examined S100A4 gene expression in six benign multinodular goitres (MNG) and 28 matched samples of adjacent normal thyroid tissue (N), primary (T) and metastatic (M) papillary thyroid carcinomas (PTC) by immunohistochemistry and real-time reverse transcription-polymerase chain reaction (RT-PCR) analysis. This gave us the advantage of directly comparing levels of S100A4 expression within the same genetic background. Using immunohistochemistry, we found that high levels of S100A4 were detected in 24 of 28 (86%) PTC specimens and their local regional lymph node or distant metastases. No S100A4 staining was observed in normal thyroid tissues and simple MNG. However, in MNG coexistent with PTC, moderate focal staining could be found in 11 of 15 MNG adjacent to PTC. The S100A4 was stained more intensely in invading fronts than in central portions of both T and M. Real-time RT-PCR analysis of primary tumours and their matched lymph node metastasis demonstrated that significantly higher S100A4 transcripts were present in metastatic tumours as compared to the primary tumours (P<0.01). These data suggest that overexpression of S100A4 is associated with thyroid tumour invasion and metastasis and it may be a potential target for therapeutic intervention.
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PMID:S100A4 (Mts1) gene overexpression is associated with invasion and metastasis of papillary thyroid carcinoma. 1626 47

The calcium-binding protein, S100A4, with an inverse association of E-cadherin, is known to correlate with prognosis in various cancers. In this study, we investigated the expression of the S100A4 and E-cadherin status in relation to the clinicopathological parameters of pancreatic cancer. The expression status of these two proteins was examined in 72 specimens of primary pancreatic carcinoma with immunohistochemistry. Fifty-six of 72 (78%) surgical specimens of primary pancreatic cancer were positive for S100A4 according to immunohistochemistry. Thirty-one (43%) specimens of pancreatic cancer showed positive expression of E-cadherin. The inverse association of S100A4 and E-cadherin expression was significant in the cancers (p < 0.0001). The S100A4 expression correlated significantly with the pathological T stage and poorer prognosis (p = 0.024). The 41 E-cadherin-negative cases showed poorer prognoses and a higher incidence of liver metastasis (p = 0.0344, p = 0.027). The 10 cases with S100A4-negative/E-cadherin-positive cancers showed a significantly better prognosis than the others (p < 0.05). The histological grade (p = 0.004), nodal status (p < 0.0001) and S100A4-positive status (p = 0.048) were highly significant independent prognostic predictors (p < 0.05). These results suggest that S100A4 overexpression combined with reduced E-cadherin expression play important roles in tumor progression and metastasis in pancreatic cancer. The combined examination of these two molecules is useful in evaluating the outcome of pancreatic cancer patient.
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PMID:Increased S100A4 expression combined with decreased E-cadherin expression predicts a poor outcome of patients with pancreatic cancer. 1686 43

Overexpression of S100A7 (psoriasin), a small calcium-binding protein, has been associated with the development of psoriasis and carcinomas in different types of epithelia, but its precise functions are still unknown. Using human tissue specimens, cultured cell lines, and a mouse model, we found that S100A7 is highly expressed in preinvasive, well-differentiated and early staged human squamous cell carcinoma of the oral cavity (SCCOC), but little or no expression was found in poorly differentiated, later-staged invasive tumors. Interestingly, our results showed that S100A7 inhibits both SCCOC cell proliferation in vitro and tumor growth/invasion in vivo. Furthermore, we demonstrated that S100A7 is associated with the beta-catenin complex, and inhibits beta-catenin signaling by targeting beta-catenin degradation via a noncanonical mechanism that is independent of GSK3beta-mediated phosphorylation. More importantly, our results also indicated that beta-catenin signaling negatively regulates S100A7 expression. Thus, this reciprocal negative regulation between S100A7 and beta-catenin signaling implies their important roles in tumor development and progression. Despite its high levels of expression in early stage SCCOC tumorigenesis, S100A7 actually inhibits SCCOC tumor growth/invasion as well as tumor progression. Downregulation of S100A7 in later stages of tumorigenesis increases beta-catenin signaling, leading to promotion of tumor growth and tumor progression.
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PMID:Reciprocal negative regulation between S100A7/psoriasin and beta-catenin signaling plays an important role in tumor progression of squamous cell carcinoma of oral cavity. 1822 93

Comparative microarray analyses provided insight into understanding transcript changes during cancer progression; however, a reproducible signature underlying breast carcinogenesis has yet to be little available. We utilized gene expression profiling to define molecular signatures associated with transformation and cancer progression in a series of isogenic human breast cancer cell lines including a normal, benign, noninvasive and invasive carcinoma. Clustering analysis revealed four distinct expression patterns based on upregulation or downregulation patterns. These profiles proved quite useful for describing breast cancer tumorigenesis and invasiveness. Downregulation of TNFSF7, S100A4, S100A7, S100A8, and S100A9 (calcium-binding protein family), and upregulation of kallikrein-5 and thrombospondin-1 were associated with transformation and progression of breast cancer cells. Importantly, downregulation of the genes was reversed by treatment with silencing inhibitors, implying the potential roles of epigenetic inactivation in breast carcinogenesis. Exogenous expressions of S100A8 and S100A9 inhibit growth in benign and noninvasive carcinoma cells, suggesting their negative role in cell proliferation. The data presented here may facilitate the identification and functional analyses of prognostic biomarkers for breast cancer.
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PMID:Molecular signatures associated with transformation and progression to breast cancer in the isogenic MCF10 model. 1880 27


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