Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0178874 (tumor progression)
 40,807 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Alpha-dystroglycan (alpha-DG) represents a highly glycosylated cell surface molecule that is expressed in the epithelial cell-basement membrane (BM) interface and plays an essential role in epithelium development and tissue organization. The alpha-DG-mediated epithelial cell-BM interaction is often impaired in invasive carcinomas, yet roles and underlying mechanisms of such an impaired interaction in tumor progression remain unclear. We report here a suppressor function of laminin-binding glycans on alpha-DG in tumor progression. In aggressive prostate and breast carcinoma cell lines, laminin-binding glycans are dramatically decreased, although the amount of alpha-DG and beta-dystroglycan is maintained. The decrease of laminin-binding glycans and consequent increased cell migration were associated with the decreased expression of beta3-N-acetylglucosaminyltransferase-1 (beta3GnT1). Forced expression of beta3GnT1 in aggressive cancer cells restored the laminin-binding glycans and decreased tumor formation. beta3GnT1 was found to be required for laminin-binding glycan synthesis through formation of a complex with LARGE, thus regulating the function of LARGE. Interaction of the laminin-binding glycans with laminin and other adhesive molecules in BM attenuates tumor cell migratory potential by antagonizing ERK/AKT phosphorylation induced by the components in the ECM. These results identify a previously undescribed role of carbohydrate-dependent cell-BM interaction in tumor suppression and its control by beta3GnT1 and LARGE.
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PMID:Tumor suppressor function of laminin-binding alpha-dystroglycan requires a distinct beta3-N-acetylglucosaminyltransferase. 1958 35

The mammalian target of rapamycin(mTOR)and its molecular pathways are supposed to be activated frequently in human renal cell carcinoma as well as other cancers. It has a kinase activity for 40S ribosomal protein kinase and eukaryotic translation initiation factor 4E-binding protein 1. These proteins, when phosphorylated, promote protein translation and RNA transcription in the nutrient-rich condition. mTOR inhibitors such as Temsirolimus (CCI779) and Everolimus (RAD001) are effective for suppressing cell growth with inhibiting mTOR kinase activity. Rapamycin and its related analogs such as Temsirolimus and Everolimus are less toxic for humans compared with other anti-VEGFR inhibitors and has been used as an immunosuppressive agent. These agents have an inhibitory activity against the mTORC1 complex. Since they do not have inhibitory activity against mTORC2 complex, the ability of mTOR inhibition by Temsirolimus is supposed to be 40 to 50% of full inhibition in mTOR kinase. Temsirolimus has modest anticancer activity against advanced clinical RCC patients with poor risk. The objective response rate was only 7%, 26% of patients experienced minor responses and another 17% of patients had stable disease that lasted 6 months. The median time to tumor progression and median survival for the study patients were 5.8 and 15.0 months, respectively. The overall survival of patients treated with Temsirolimus alone was statistically longer than in those treated with IFN alone in the 626 cases in phase II study. Combinations of mTOR with other anti- VEGFR agents were not effective. Vertical therapies of mTOR inhibitor in combination with AKT inhibitors, or newly development of stronger mTOR kinase which can suppress both mTORC1 and mTORC2 are planned at present.
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PMID:[Mammalian target of rapamycin, its mode of action and clinical response in metastatic clear cell carcinoma]. 1962 Jul 95

Osteopontin (OPN) is highly expressed in cancer patients and plays important roles in many stages of tumor progression, such as anti-apoptosis, proliferation, and metastasis. From functional screening of human cDNA library, we isolated OPN as a caspase-8 substrate that regulates cell death during hypoxia/reoxygenation (Hyp/RO). In vitro cleavage assays demonstrate that OPN is cleaved at Asp-135 and Asp-157 by caspase-8. Cellular cleavage of OPN is observed in apoptotic cells exposed to Hyp/RO among various apoptotic stimuli and its cleavage is blocked by zVAD or IETD caspase inhibitor. Further, over-expression of OPN, the form with secretion signal, inhibits Hyp/RO-induced cell death. Caspase cleavage-defective OPN mutant (OPN D135A/D157A) is more efficient to suppress Hyp/RO-induced cell death than wild-type OPN. OPN D135A/D157A sustains AKT activity to increase cell viability through inhibition of caspase-9 during Hyp/RO. In addition, OPN is highly induced in some tumor cells during Hyp/RO, such as HeLa and Huh-7 cells, which is associated with their resistance to Hyp/RO by sustaining AKT activity. Notably, OPN C-terminal cleavage fragment produced by caspase-8 is detected in the nucleus. Plasmid-encoded expression of OPN C-terminal cleavage fragment increases p53 protein level and induces apoptosis of wild-type mouse embryonic fibroblast cells, but not p53(-/-) mouse embryonic fibroblast cells. These observations suggest that the protective function of OPN during Hyp/RO is inactivated via the proteolytic cleavage by caspase-8 and its cleavage product subsequently induces cell death via p53, postulating caspase-8 as a negative regulator of tumorigenic activity of OPN.
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PMID:Intracellular cleavage of osteopontin by caspase-8 modulates hypoxia/reoxygenation cell death through p53. 1970 14

The role of PI-3-K in the regulation of mitochondrial functions is becoming a field that draws attentions from cancer as well as metabolic diseases. In this review, we focus on the action of the major downstream target of PI-3-K, the serine/threonine kinase AKT, a proto-oncoprotein. We reviewed the functions of AKT in the mitochondrial intrinsic apoptosis pathway. We analyzed how AKT regulates the different factors in the Bcl-2 family of anti- and pro-apoptotic factors either directly or indirectly. We further reviewed the role of AKT in regulating mitochondrial coupled glycolysis through hexokinase II and VDAC. This review is focused on the function of PI-3-K and AKT at the mitochondrial. These interactions between the mitogenic PI-3-K/AKT and the mitochondrial function may provide clues on how tumors overcome the ongoing need for nutrient supply. Such characterizations can provide new targets for drug discoveries targeted at blocking tumor progression.
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PMID:PI-3-K and AKT: Onto the mitochondria. 1972 99

In the past 3 years, altered expression of the HEF1/CAS-L/NEDD9 scaffolding protein has emerged as contributing to cancer metastasis in multiple cancer types. However, whereas some studies have identified elevated NEDD9 expression as prometastatic, other work has suggested a negative role in tumor progression. We here show that the Nedd9-null genetic background significantly limits mammary tumor initiation in the MMTV-polyoma virus middle T genetic model. Action of NEDD9 is tumor cell intrinsic, with immune cell infiltration, stroma, and angiogenesis unaffected. The majority of the late-appearing mammary tumors of MMTV-polyoma virus middle T;Nedd9(-/-) mice are characterized by depressed activation of proteins including AKT, Src, FAK, and extracellular signal-regulated kinase, emphasizing an important role of NEDD9 as a scaffolding protein for these prooncogenic proteins. Analysis of cells derived from primary Nedd9(+/+) and Nedd9(-/-) tumors showed persistently reduced FAK activation, attachment, and migration, consistent with a role for NEDD9 activation of FAK in promoting tumor aggressiveness. This study provides the first in vivo evidence of a role for NEDD9 in breast cancer progression and suggests that NEDD9 expression may provide a biomarker for tumor aggressiveness.
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PMID:NEDD9 promotes oncogenic signaling in mammary tumor development. 1973 60

Aberrant activation of the PI3K/Akt/mTOR pathway is found in many types of cancer and thus plays a major role in breast cancer cell proliferation and anti-cancer drug resistance. The mechanisms involved in the activation of this pathway include: constitutively activated receptor tyrosine kinases (IGF/IGFR, ErbB, FGF/FGFR systems) leading to constitutive activation of PI3K; loss of PTEN function; PI3K mutations; aberrant activation of Akt, eIF4E, 4E-BP1 and p70S6K. These alterations trigger a cascade of biological events, from cell growth and proliferation to survival and migration, which contribute to tumor progression. Therefore, the PI3K/AKT/mTOR pathway is considered an attractive target for the development of novel anti-cancer molecules, and several specific tyrosine kinase inhibitors and signal transduction inhibitors specifically targeting the kinases involved in this pathway have been developed. Many of these inhibitors currently under clinical evaluation represent a promising approach for the treatment of breast cancer patients. This review provides an overview of the most recent patents, of pre-clinical and clinical studies of inhibitors targeting the different members and/or activators of the PI3K/Akt/mTOR pathway, used alone or in combination with other targeted agents for the treatment of breast cancer.
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PMID:Inhibitors of the PI3K/Akt/mTOR pathway: new hope for breast cancer patients. 1975 Dec 11

Mutations of SMAD4/DPC4 are found in about 60% of human invasive pancreatic ductal adenocarcinomas (PDACs); yet, the manner in which SMAD4 deficiency enhances tumorigenesis remains elusive. Using a Cre-LoxP approach, we generated a mutant mouse carrying a targeted deletion of Smad4 in the pancreas. We showed that the absence of Smad4 alone did not trigger pancreas tumor formation; however, it increased the expression of an inactivated form of Pten, suggesting a role of Pten in preventing Smad4-/- cells from undergoing malignancy. To investigate this, we disrupted both Pten and Smad4. We showed that Pten deficiency initiated widespread premalignant lesions, and a low tumor incidence that was significantly accelerated by Smad4-deficiency. The absence of Smad4 in a Pten-mutant background enhanced cell proliferation and triggered transdifferentiation from acinar, centroacinar and islet cells, accompanied by activation of Notch1 signaling. We showed that all tumors developed in the Smad4/Pten-mutant pancreas exhibited high levels of pAKT and mTOR, and that about 50 and 83% of human pancreatic cancers examined showed increased pAKT and pmTOR, respectively. Besides the similarity in gene expression, the pAKT and/or pmTOR-positive human PDACs and mouse pancreatic tumors also shared some histopathological similarities. These observations indicate that Smad4/Pten-mutant mice mimic the tumor progression of human pancreatic cancers that are driven by activation of the AKT-mTOR pathway, and uncovered a synergistic action of Smad4 and Pten in repressing pancreatic tumorigenesis.
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PMID:Synergistic action of Smad4 and Pten in suppressing pancreatic ductal adenocarcinoma formation in mice. 1990 70

The identification of genes involved in carcinogenesis and tumor progression is of great interest since these genes might be feasible as candidates for new tumor-targeted therapy strategies. Chimeric tumor suppressor-1 (CTS-1), an artificial synthetic variant of p53, resists common p53 inactivation and could therefore be defined as a dominant-positive p53 variant. Overexpression of CTS-1 induces caspase-independent cell death. We used whole-genome microarray expression analysis in a parental (229(P)) and a CTS-1-resistant glioma cell line (229(Res)) to analyze alterations in gene expression in Ad-CTS-1-infected and in uninfected parental and resistant cells. In total, 700 genes were differentially expressed in infected and 313 genes in uninfected 229(Res) versus 229(P) cells. Ingenuity Pathway Analysis determined a variety of differentially expressed genes in Ad-CTS-1-infected cells that were members of intracellular networks with central tumor-involved players such as nuclear factor-kappaB (NFkappaB), protein kinase B/AKT or transforming growth factor-beta. Here we focused on the function of NFkappaB in Ad-CTS-1-mediated cell death in glioma. NFkappaB was activated in Ad-CTS-1-infected 229(P) but not 229(Res) cells. NFkappaB activation was accompanied by the induction of cell death in parental cells. Inhibition of NFkappaB activity by expression of an IkappaB super repressor or upregulation of the NFkappaB-linked gene Bex protected parental cells to Ad-CTS-1-induced cell death, whereas knockdown of Bex sensitized both parental and resistant cells. Taken together, these data suggest that activation of the normally antiapoptotic protein NFkappaB does not always necessarily protect cells from apoptosis but, in the glioma cell lines tested so far, and in an environment where p53 is constitutively active, also leads to the induction of cell death.
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PMID:Gene expression profile in a glioma cell line resistant to cell death induced by the chimeric tumor suppressor-1 (CTS-1), a dominant-positive variant of p53--the role of NFkappaB. 2001 65

Aberrant expression and mutations of thyroid hormone receptor genes (TRs) are closely associated with several types of human cancers. To test the hypothesis that TRs could function as tumor suppressors, we took advantage of mice with deletion of all functional TRs (TRalpha1(-/-)TRbeta(-/-) mice). As these mice aged, they spontaneously developed follicular thyroid carcinoma with pathological progression from hyperplasia to capsular invasion, vascular invasion, anaplasia and metastasis to the lung, similar to human thyroid cancer. Detailed molecular analysis revealed that known tumor promoters such as pituitary tumor-transforming gene were activated and tumor suppressors such as peroxisome proliferator-activated receptor gamma and p53 were suppressed during carcinogenesis. In addition, consistent with the human cancer, AKT-mTOR-p70(S6K) signaling and vascular growth factor and its receptor were activated to facilitate tumor progression. This report presents in vivo evidence that functional loss of both TRalpha1 and TRbeta genes promotes tumor development and metastasis. Thus, TRs could function as tumor suppressors in a mouse model of metastatic follicular thyroid cancer.
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PMID:Thyroid hormone receptors are tumor suppressors in a mouse model of metastatic follicular thyroid carcinoma. 2006 85

Angiogenesis is observed in many diseases, such as tumor progression, diabetes and rheumatoid arthritis; it is a process that involves proliferation, migration, differentiation and tube formation of endothelial cells. Vascular endothelial growth factor (VEGF) plays an important role in angiogenesis by induction of these endothelial functions. Thus, inhibition of these critical angiogenic steps is a practical therapeutic strategy for those diseases. NP-184 is a substituted benzimidazole analogue which exhibits a potent anti-thrombotic activity. In this report, NP-184 inhibited the viability of human umbilical vascular endothelial cells (HUVEC) in a concentration-dependent manner, and caused cell apoptosis as examined by cell-cycle analysis and Annexin V staining with flow cytometry. NP-184 also concentration-dependently inhibited the HUVEC migration, tube formation on Matrigel, and rat aortic ring sprouting stimulated by VEGF. Regarding the intracellular signal transduction, NP-184 concentration-dependently interfered with the activation of AKT, ERK and the nuclear translocation of NF-kappaB. In vivo study showed that NP-184 dose-dependently reduced angiogenesis in Matrigel plug assay. These results indicate that NP-184 is a potential candidate for developing the treatment of angiogenesis related-diseases.
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PMID:A novel compound, NP-184, inhibits the vascular endothelial growth factor induced angiogenesis. 2006 87


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