Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
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Gene/Protein
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Query: EC:2.7.10.2 (
focal adhesion kinase
)
44,029
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
PTEN is a tumor suppressor frequently inactivated in brain, prostate, and uterine cancers that acts as a phosphatase on phosphatidylinositol-3,4,5-trisphosphate, antagonizing the activity of the phosphatidylinositol 3'-OH kinase. PTEN manifests its tumor suppressor function in most tumor cells by inducing G(1)-phase cell cycle arrest. To study the mechanism of cell cycle arrest, we established a tetracycline-inducible expression system for PTEN in cell lines lacking this gene. Expression of wild-type PTEN but not of mutant forms unable to dephosphorylate phosphoinositides reduced the expression of cyclin D1. Cyclin D1 reduction was accompanied by a marked decrease in endogenous
retinoblastoma
(Rb) protein phosphorylation on cyclin D/CDK4-specific sites, showing an early negative effect of PTEN on Rb inactivation. PTEN expression also prevented cyclin D1 from localizing to the nucleus during the G(1)- to S-phase cell cycle transition. The PTEN-induced localization defect and the cell growth arrest could be rescued by the expression of a nucleus-persistent mutant form of cyclin D1, indicating that an important effect of PTEN is at the level of nuclear availability of cyclin D1. Constitutively active Akt/
PKB
kinase counteracted the effect of PTEN on cyclin D1 translocation. The data are consistent with an oncogenesis model in which a lack of PTEN fuels the cell cycle by increasing the nuclear availability of cyclin D1 through the Akt/
PKB
pathway.
...
PMID:PTEN induces cell cycle arrest by decreasing the level and nuclear localization of cyclin D1. 1291 36
The specific targeting of critical signaling molecules may provide efficient therapies for T-cell acute lymphoblastic leukemia (T-ALL). However, target identification and drug development are limited by insufficient numbers of primary T-ALL cells and by their high rate of spontaneous apoptosis. We established a human interleukin-7 (IL-7)-dependent T-ALL cell line, TAIL7, that maintains several biologic and signaling properties of its parental leukemia cells. TAIL7 cells are pre-T-ALL cells that proliferate in response to IL-7 and IL-4. IL-7 stimulation of TAIL7 cells prevents spontaneous in vitro apoptosis and induces cell activation and cell cycle progression. The signaling events triggered by IL-7 include down-regulation of p27(kip1) and hyperphosphorylation of
retinoblastoma
protein (Rb). Stimulation of TAIL7 cells by IL-7 leads to phosphorylation of
Janus kinase 3
(
JAK3
), signal transducer and activator of transcription 5 (STAT5), Akt/
PKB
(protein kinase B), and extracellular-regulated kinase 1 and 2 (Erk1/2). Importantly, specific blockade of
JAK3
by its inhibitor WHI-P131 abrogates the IL-7-mediated proliferation and survival of TAIL7 cells, suggesting that activation of
JAK3
is critical for IL-7 responsiveness by these cells. Because TAIL7 cells seem to be a biologic surrogate for primary leukemia T cells, this cell line constitutes a valuable tool for the study of the signaling pathways implicated in T-ALL. Exploitation of this cell line should allow the identification of molecular targets and promote the rational design and validation of antileukemia signaling inhibitors.
...
PMID:IL-7-dependent human leukemia T-cell line as a valuable tool for drug discovery in T-ALL. 1461 84
Capsaicin (trans-8-methyl-N-vanillyl-6-nonenamide), a natural product of Capsicum species, is known to induce excitation of nociceptive terminals involved in pain perception. Recent studies have also shown that capsaicin not only has chemopreventive properties against certain carcinogens and mutagens but also exerts anticancer activity. Here, we demonstrated the antiangiogenic activity of capsaicin using in vitro and in vivo assay systems. In vitro, capsaicin inhibited vascular endothelial growth factor (VEGF) -induced proliferation, DNA synthesis, chemotactic motility, and capillary-like tube formation of primary cultured human endothelial cells. Capsaicin inhibited both VEGF-induced vessel sprouting in rat aortic ring assay and VEGF-induced vessel formation in the mouse Matrigel plug assay. Moreover, capsaicin was able to suppress tumor-induced angiogenesis in chick chorioallantoic membrane assay. Capsaicin caused G(1) arrest in endothelial cells. This effect correlated with the down-regulation of the expression of cyclin D1 that led to inhibition of cyclin-dependent kinase 4-mediated phosphorylation of
retinoblastoma
protein. Signaling experiments show that capsaicin inhibits VEGF-induced p38 mitogen-activated protein kinase, p125(
FAK
), and AKT activation, but its molecular target is distinct from the VEGF receptor KDR/Flk-1. Taken together, these results demonstrate that capsaicin is a novel inhibitor of angiogenesis and suggest that it may be valuable to develop pharmaceutical drugs for treatment of angiogenesis-dependent human diseases such as tumors.
...
PMID:Capsaicin inhibits in vitro and in vivo angiogenesis. 1474 80
Smooth muscle cell (SMC) proliferation is suppressed in intact blood vessels but stimulated in atherosclerosis, restenosis after angioplasty, and vein graft disease. The cyclin-dependent kinase inhibitors, including p27(Kip1), play important roles in maintaining SMC quiescence. Levels of p27(Kip1) are dependent on attachment to and the composition of the extracellular matrix (ECM). Here we sought to elucidate mechanisms underlying the ECM-dependent regulation of p27(Kip1) and hence, SMC proliferation. Serum stimulation decreased p27(Kip1) levels in isolated SMC but not in rat aorta. The effect was post-translational and mediated by proteasomal degradation. We studied the S-phase-associated kinase protein-2 (Skp-2), an F-box protein involved in ubiquitination and proteasome-mediated degradation. Skp-2 protein is strongly induced by serum from undetectable levels in isolated SMCs but remains undetectable in aorta; Skp-2 mRNA is also lower in aorta. Overexpression of wild-type Skp-2 in SMCs decreased p27(Kip1) levels, whereas dominant negative F-box deleted mutant (DeltaF-Skp-2) Skp-2 increased p27(Kip1) levels. Furthermore, hyperphosphorylation of
retinoblastoma
protein and SMC proliferation were also reciprocally affected by wild-type and dominant negative Skp-2. Skp-2 expression was absolutely dependent on cell attachment to the ECM and was inhibited by laminin and type-1 fibrillar collagen but increased by fibronectin. Expression of Skp-2 protein, but not mRNA, was associated with
focal adhesion kinase
(
FAK
) activity and inhibited by overexpression of
FAK
-related non-kinase and a dominant negative
FAK
(Y397F) mutant. Furthermore, the inhibition of Skp-2 expression by dominant negative
FAK
was reversed by the proteasome inhibitor MG-132. Taken together, these data demonstrate that the vascular ECM controls SMC proliferation via
FAK
-dependent regulation of Skp-2 protein stability.
...
PMID:Focal adhesion kinase (FAK)-dependent regulation of S-phase kinase-associated protein-2 (Skp-2) stability. A novel mechanism regulating smooth muscle cell proliferation. 1520 31
Mouse Formin (Fmn1) is an actin regulator interacting with Profilin,
SRC
, EMS1, FNBP1, FNBP2, FNBP3, FNBP4, WBP4 and alpha-catenin. FMN1, FHOD1, FHOD3, GRID2IP and FHDC1 are non-FDD-type Formin homology proteins, while FMNL1, FMNL2, FMNL3, DIAPH1, DIAPH2, DIAPH3, DAAM1 and DAAM2 are FDD-type Formin homology proteins. Here, we characterized human FMN2 gene by using bioinformatics. Complete coding sequence of human FMN2 cDNA was determined by assembling AL359918, AL513342, AL590490, AL646016 genome sequences, AF218941 partial cDNA, and AF218942 partial cDNA. FMN2 mRNA was expressed in fetal brain, adult whole brain, hypothalamus, retina, pancreatic islet and germinal-center B cells. Among various human tumors, FMN2 mRNA was expressed in parathyloid tumor, glioblastoma,
retinoblastoma
and chondrosarcoma. Human FMN2 (1722 aa) showed 74.7% total-amino-acid identity with mouse Fmn2, and 31.9% total-amino-acid identity with human FMN1. Although N-terminal half was divergent between FMN2 orthologs and FMN1 orthologs, FH1 and FH2 domains were conserved among FMN2 and FMN1 orthologs. Exon-intron structure was conserved between FMN2 and FMN1 genes. RYR2-FMN2-CKTSF1B2 (PRDC) locus at human chromosome 1q43 and RYR3-FMN1-CKTSF1B1 (Gremlin) locus at human chromosome 15q13-q14 were paralogous regions (paralogons) within the human genome. This is the first report on comprehensive characterization of the human FMN2 gene.
...
PMID:Characterization of FMN2 gene at human chromosome 1q43. 1528 2
The review by D.T. Hughes examined the role of cytogenetics in cancer research in 1964. Despite the technical limitations of the day, he highlighted a number of known abnormalities which were to turn out to be crucial in our understanding of cancer genetics over the subsequent 40 years. These included the Philadelphia translocation and the Burkitt's lymphoma-associated marker chromosomes. In addition, he mentioned that a deleted chromosome had been observed in an example of
retinoblastoma
and double-minute chromosomes in neuroblastoma. The study of these events led to the identification of the key genes involved (BCR,
ABL
, C-MYC, RB1 and N-MYC) and served as models for substantial further work. We review some of the technical advances in the field of molecular cytogenetics and show how they can be applied to the events reviewed by Hughes.
...
PMID:Understanding cancer at the chromosome level: 40 years of progress. 587 19
Rho GTPases are major regulators of cytoskeletal dynamics, but they also affect cell proliferation, transformation, and oncogenesis. RhoE, a member of the Rnd subfamily that does not detectably hydrolyze GTP, inhibits RhoA/ROCK signaling to promote actin stress fiber and focal adhesion disassembly. We have generated fibroblasts with inducible RhoE expression to investigate the role of RhoE in cell proliferation. RhoE expression induced a loss of stress fibers and cell rounding, but these effects were only transient. RhoE induction inhibited cell proliferation and serum-induced S-phase entry. Neither ROCK nor RhoA inhibition accounted for this response. Consistent with its inhibitory effect on cell cycle progression, RhoE expression was induced by cisplatin, a DNA damage-inducing agent. RhoE-expressing cells failed to accumulate cyclin D1 or p21(cip1) protein or to activate E2F-regulated genes in response to serum, although ERK, PI3-K/Akt,
FAK
, Rac, and cyclin D1 transcription was activated normally. The expression of proteins that bypass the
retinoblastoma
(pRb) family cell cycle checkpoint, including human papillomavirus E7, adenovirus E1A, and cyclin E, rescued cell cycle progression in RhoE-expressing cells. RhoE also inhibited Ras- and Raf-induced fibroblast transformation. These results indicate that RhoE inhibits cell cycle progression upstream of the pRb checkpoint.
...
PMID:RhoE inhibits cell cycle progression and Ras-induced transformation. 1534 47
We report a mechanism by which the adapter protein Gene 33 (also called RALT and MIG6) regulates epidermal growth factor receptor (EGFR) signaling. We find that Gene 33 inhibits EGFR autophosphorylation and specifically blunts epidermal growth factor (EGF)-induced activation and/or phosphorylation of Ras, ERK, JNK, Akt/
PKB
, and
retinoblastoma
protein. The Ack homology domain of Gene 33, which contains the previously identified EGFR binding domain, is both necessary and sufficient for this inhibition of EGFR autophosphorylation. The endogenous Gene 33 polypeptide is induced by EGF, platelet-derived growth factor, serum, and dexamethasone (Dex) in Rat 2 rat fibroblasts. Dex induces Gene 33 expression and inhibits EGFR phosphorylation and EGF signaling. RNA interference-mediated silencing of Gene 33 significantly reverses this effect. Overexpression of Gene 33 completely blocks EGF-induced protein and DNA synthesis in Rat 2 cells, whereas gene 33 RNA interference substantially enhances EGF-induced protein and DNA synthesis in Rat 2 cells. Our results indicate that Gene 33 is a physiological feedback inhibitor of the EGFR, functioning to inhibit EGFR phosphorylation and all events induced by EGFR activation. Our results also indicate a role for Gene 33 in the suppression, by Dex, of EGF signaling pathways. We propose that Gene 33 may function in the cross-talk between EGF signaling and other mitogenic and/or stress signaling pathways.
...
PMID:Gene 33 is an endogenous inhibitor of epidermal growth factor (EGF) receptor signaling and mediates dexamethasone-induced suppression of EGF function. 1555 44
We studied in vitro effects of glycogen synthase kinase 3beta (GSK3beta)-inhibitor lithium on the growth of hepatocellular carcinoma (HCC) cells. Lithium induced strong growth inhibition (> 70%) in 75% (n = 9 of 12) of cell lines, apparently independent from the status of major genes that are mutated in HCC including p53, p16(INK4a), beta-catenin and Axin1. Comparative studies with a growth-sensitive Huh7 and growth-resistant Hep40 cell lines showed that lithium induces growth arrest in Huh7 cells but not in Hep40 cells. Lithium induced the accumulation of N-terminally phosphorylated inactive form of GSK3beta with concomitant increase in beta-catenin and beta-catenin/TCF transcriptional activity in both cell lines. This suggests that lithium-mediated HCC growth inhibition is independent of its well-known stimulatory effect on Wnt-beta-catenin signaling. The main differences between Huh7 and Hep40 responses to lithium treatment were observed at the levels
PKB
/Akt and cyclin E proteins. Lithium induced depletion of both proteins in growth-sensitive Huh7, but not in growth-resistant Hep40 cells.
PKB
/Akt and Cyclin E are 2 major proteins that are known to be constitutively active in HCC. The targeting of both proteins with lithium may be the main reason why most HCC cells are responsive to lithium-mediated growth inhibition, independent of their p53,
retinoblastoma
and Wnt-beta-catenin pathways. The exploration of molecular mechanisms involved in lithium-mediated growth inhibition in relation with
PKB
/Akt and cyclin E downregulation may provide new insights for therapy of liver tumors.
...
PMID:Lithium-mediated downregulation of PKB/Akt and cyclin E with growth inhibition in hepatocellular carcinoma cells. 1572 55
The
retinoblastoma
tumor suppressor protein (Rb) is best known as a repressor of genes involved in cell cycle progression. Rb has also been implicated in activation of transcription, in particular by nuclear receptors (NRs) and by differentiation-related transcription factors, but the relevance of this activity is unclear. We show that Rb and the related proteins p107 and p130 enhance the activity of NRs related to NGFI-B (Nur factors) through direct interactions with NGFI-B and
SRC
-2. Although recruitment of
SRC
/p160 coactivators to the NGFI-B AF1 domain is independent of Rb, its presence enhances
SRC
-dependent transcription. Rb potentiation of
SRC
coactivators is exerted on a subset (Nur factors, hepatocyte nuclear factor-4 (HNF-4), SF-1, and ER) but not all NRs. The levels of Rb-related proteins modulate hormone responsiveness of the NGFI-B-dependent pituitary proopiomelanocortin gene and HNF-4-dependent transcription during enterocyte differentiation. Increased Rb expression upon cell differentiation may promote differentiated functions, at least in part, by potentiation of NR activity.
...
PMID:Rb enhances p160/SRC coactivator-dependent activity of nuclear receptors and hormone responsiveness. 1576 62
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