DNA-PK phosphorylation of IGFBP-3 is required to Prevent Apoptosis in Retinal Endothelial cells cultured in High Glucose.

DNA-PK phosphorylation of IGFBP-3 is required to Prevent Apoptosis in Retinal Endothelial cells cultured in High Glucose.

Invest Ophthalmol Vis Sci. 2013 Apr 4;

Authors: Zhang Q, Steinle JJ

Abstract
PURPOSE: The goal of this study was to determine whether Compound 49b stimulates insulin-like growth factor binding protein-3 (IGFBP-3) activation in retinal endothelial cells (REC) through DNA-dependent protein kinase (DNA-PK). METHODS: REC were grown in normal glucose (5 mM) or high glucose medium (25 mM). Some cells were transfected with protein kinase A (PKA) siRNA, following treatment with 50 nM Compound 49b, a novel ?-adrenergic receptor agonist. Cell proteins were extracted and analyzed for DNA-PK expression by Western blotting. Additional cells were treated with or without NU7441 (a specific DNA-PK inhibitor) prior to Compound 49b treatment. Cell lysates were processed for IGFBP-3 ELISA analyses and Western blotting to measure casein kinase 2 (CK2). Immunoprecipitation for total and phospho-IGFBP-3 and cell death measurements were done after transfection with the S156A IGFBP-3 mutation (key phosphorylation site involved in DNA-PK) plasmid DNA. RESULTS: Compound 49b required DNA-PK to activate IGFBP-3 in REC. IGFBP-3 activation was significantly reduced following treatment with either the DNA-PK inhibitor or following transfection with the IGFBP-3 S156A mutant plasmid (p < 0.05). Significant increases in cell death were also observed in cells transfected with the IGFBP-3 S156A mutant plasmid (p < 0.05). Casein kinase levels were not altered after treatment with NU7741 or Compound 49b. CONCLUSIONS: Our finding suggested Compound 49b induces DNA-PK levels through PKA activity. DNA-PK is required for Compound 49b-induced activation of IGFBP-3, leading to inhibition of REC cell death.

PMID: 23557743 [PubMed - as supplied by publisher]

chir-258 dovitinib dna-pk

In Vivo c-Met Pathway Inhibition Depletes Human Glioma Xenografts of Tumor-Propagating Stem-Like Cells.

In Vivo c-Met Pathway Inhibition Depletes Human Glioma Xenografts of Tumor-Propagating Stem-Like Cells.

Transl Oncol. 2013 Apr;6(2):104-11

Authors: Rath P, Lal B, Ajala O, Li Y, Xia S, Kim J, Laterra J

Abstract
Solid malignancies contain sphere-forming stem-like cells that are particularly efficient in propagating tumors. Identifying agents that target these cells will advance the development of more effective therapies. Recent converging evidence shows that c-Met expression marks tumor-initiating stem-like cells and that c-Met signaling drives human glioblastoma multiforme (GBM) cell stemness in vitro. However, the degree to which tumor-propagating stem-like cells depend on c-Met signaling in histologically complex cancers remains unknown. We examined the effects of in vivo c-Met pathway inhibitor therapy on tumor-propagating stem-like cells in human GBM xenografts. Animals bearing pre-established tumor xenografts expressing activated c-Met were treated with either neutralizing anti- hepatocyte growth factor (HGF) monoclonal antibody L2G7 or with the c-Met kinase inhibitor PF2341066 (Crizotinib). c-Met pathway inhibition inhibited tumor growth, depleted tumors of sphere-forming cells, and inhibited tumor expression of stem cell markers CD133, Sox2, Nanog, and Musashi. Withdrawing c-Met pathway inhibitor therapy resulted in a substantial rebound in stem cell marker expression concurrent with tumor recurrence. Cells derived from xenografts treated with anti-HGF in vivo were depleted of tumor-propagating potential as determined by in vivo serial dilution tumor-propagating assay. Furthermore, daughter xenografts that did form were 12-fold smaller than controls. These findings show that stem-like tumor-initiating cells are dynamically regulated by c-Met signaling in vivo and that c-Met pathway inhibitors can deplete tumors of their tumor-propagating stem-like cells.

PMID: 23556031 [PubMed - in process]

ecdysone chir-258 dovitinib

In Vivo c-Met Pathway Inhibition Depletes Human Glioma Xenografts of Tumor-Propagating Stem-Like Cells.

In Vivo c-Met Pathway Inhibition Depletes Human Glioma Xenografts of Tumor-Propagating Stem-Like Cells.

Transl Oncol. 2013 Apr;6(2):104-11

Authors: Rath P, Lal B, Ajala O, Li Y, Xia S, Kim J, Laterra J

Abstract
Solid malignancies contain sphere-forming stem-like cells that are particularly efficient in propagating tumors. Identifying agents that target these cells will advance the development of more effective therapies. Recent converging evidence shows that c-Met expression marks tumor-initiating stem-like cells and that c-Met signaling drives human glioblastoma multiforme (GBM) cell stemness in vitro. However, the degree to which tumor-propagating stem-like cells depend on c-Met signaling in histologically complex cancers remains unknown. We examined the effects of in vivo c-Met pathway inhibitor therapy on tumor-propagating stem-like cells in human GBM xenografts. Animals bearing pre-established tumor xenografts expressing activated c-Met were treated with either neutralizing anti- hepatocyte growth factor (HGF) monoclonal antibody L2G7 or with the c-Met kinase inhibitor PF2341066 (Crizotinib). c-Met pathway inhibition inhibited tumor growth, depleted tumors of sphere-forming cells, and inhibited tumor expression of stem cell markers CD133, Sox2, Nanog, and Musashi. Withdrawing c-Met pathway inhibitor therapy resulted in a substantial rebound in stem cell marker expression concurrent with tumor recurrence. Cells derived from xenografts treated with anti-HGF in vivo were depleted of tumor-propagating potential as determined by in vivo serial dilution tumor-propagating assay. Furthermore, daughter xenografts that did form were 12-fold smaller than controls. These findings show that stem-like tumor-initiating cells are dynamically regulated by c-Met signaling in vivo and that c-Met pathway inhibitors can deplete tumors of their tumor-propagating stem-like cells.

PMID: 23556031 [PubMed - in process]

dovitinib dna-pk coxinhibitors

Optimizing megakaryocyte polyploidization by targeting multiple pathways of cytokinesis.

Related Articles

Optimizing megakaryocyte polyploidization by targeting multiple pathways of cytokinesis.

Transfusion. 2012 Nov;52(11):2406-13

Authors: Avanzi MP, Chen A, He W, Mitchell WB

Abstract
BACKGROUND: Large-scale in vitro production of platelets (PLTs) from cord blood stem cells is one goal of stem cell research. One step toward this goal will be to produce polyploid megakaryocytes capable of releasing high numbers of PLTs. Megakaryocyte polyploidization requires distinct cytoskeletal and cellular mechanisms, including actin polymerization, myosin activation, microtubule formation, and increased DNA production. In this study we variably combined inhibition of these principal mechanisms of cytokinesis with the goal of driving polyploidization in megakaryocytes.
STUDY DESIGN AND METHODS: Megakaryocytes were derived from umbilical cord blood and cultured with reagents that inhibit distinct mechanisms of cytokinesis: Rho-Rock inhibitor (RRI), Src inhibitor (SI), nicotinamide (NIC), aurora B inhibitor (ABI), and myosin light chain kinase inhibitor (MLCKI). Combinations of reagents were used to determine their interactions and to maximize megakaryocyte ploidy.
RESULTS: Treatment with RRI, NIC, SI, and ABI, but not with MLCKI, increased the final ploidy and RRI was the most effective single reagent. RRI and MLCKI, both inhibitors of MLC activation, resulted in opposite ploidy outcomes. Combinations of reagents also increased ploidy and the use of NIC, SI, and ABI was as effective as RRI alone. Addition of MLCKI to NIC, SI, and ABI reached the highest level of polyploidization.
CONCLUSION: Megakaryocyte polyploidization results from modulation of a combination of distinct cytokinesis pathways. Reagents targeting distinct cytoskeletal pathways produced additive effects in final megakaryocyte ploidy. The RRI, however, showed no additive effect but produced a high final ploidy due to overlapping inhibition of multiple cytokinesis pathways.

PMID: 22612069 [PubMed - indexed for MEDLINE]

coxinhibitors c-met inhibitors zm-447439

Semi-mechanistic modeling of the interaction between the central and peripheral effects in the antinociceptive response to lumiracoxib in rats.

Related Articles

Semi-mechanistic modeling of the interaction between the central and peripheral effects in the antinociceptive response to lumiracoxib in rats.

AAPS J. 2012 Dec;14(4):904-14

Authors: V�lez de Mendiz�bal N, V�squez-Bahena D, Jim�nez-Andrade JM, Ortiz MI, Casta�eda-Hern�ndez G, Troc�niz IF

Abstract
The model-based approach was undertaken to characterize the interaction between the peripheral and central antinociceptive effects exerted by lumiracoxib. The effects of intraplantar and intrathecal administrations and of fixed ratio combinations of lumiracoxib simultaneously administered by these two routes were evaluated using the formalin test in rats. Pain-related behavior data, quantified as the number of flinches of the injected paw, were analyzed using a population approach with NONMEM 7. The pain response during the first phase of the formalin test, which was insensitive to lumiracoxib, was modeled using a monoexponential decay. The second phase, which was sensitive to lumiracoxib, was described incorporating synthesis and degradation processes of pain mediators that were recruited locally after tissue injury. Upregulation at the local level and in the central nervous system (CNS) was set to be proportional to the predicted levels of pain mediators in the local (injured) compartment. Results suggest a greater role of upregulated COX-2(Local) in generating the pain response compared to COX-2(CNS). Drug effects were described as inhibition of upregulated COX-2. The model adequately described the time course of nociception after formalin injection in the absence or presence of lumiracoxib administered locally and/or spinally. Data suggest that the overall response is the additive outcome of drug effects at the peripheral and central compartments, with predominance of peripheral mechanisms. Application of modeling opens new perspectives for understanding the overall mechanism of action of analgesic drugs.

PMID: 22968496 [PubMed - indexed for MEDLINE]

coxinhibitors c-met inhibitors zm-447439

Extrarenal perivascular epithelioid cell tumors (PEComas) respond to mTOR inhibition: clinical and molecular correlates.

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Extrarenal perivascular epithelioid cell tumors (PEComas) respond to mTOR inhibition: clinical and molecular correlates.

Int J Cancer. 2013 Apr 1;132(7):1711-7

Authors: Dickson MA, Schwartz GK, Antonescu CR, Kwiatkowski DJ, Malinowska IA

Abstract
Perivascular epithelioid cell tumors (PEComas) are a group of rare mesenchymal tumors that typically show both melanocytic and smooth muscle cell features. Some types of PEComa are seen at high frequency in tuberous sclerosis complex (TSC). The TSC1 and TSC2 genes are commonly mutated in both TSC-associated and sporadic PEComas, and mTOR signaling pathway activation is also common in these tumors. Preliminary reports have indicated that the mTOR inhibitors sirolimus and related drugs have activity in some patients with non-TSC-associated PEComa. Here, we report on the use of these medications in the treatment of five consecutive patients with extrarenal nonpulmonary PEComas seen at one institution. Three complete responses, one partial response and one case of progression were seen. Molecular studies identified TSC2 aberrations in four of these patients, and TFE3 translocation was excluded in the resistant case. A review of all published cases as well as those reported here indicates that partial or complete response was seen in 6 of 11 PEComas, with 5 of 6 having a complete response. These findings highlight the consistent though incomplete activity of mTOR inhibitors in the treatment of PEComas.

PMID: 22927055 [PubMed - indexed for MEDLINE]

zm-447439 rad001 ecdysone

Association of a MET genetic variant with autism-associated maternal autoantibodies to fetal brain proteins and cytokine expression.

Related Articles

Association of a MET genetic variant with autism-associated maternal autoantibodies to fetal brain proteins and cytokine expression.

Transl Psychiatry. 2011;1:e48

Authors: Heuer L, Braunschweig D, Ashwood P, Van de Water J, Campbell DB

Abstract
The contribution of peripheral immunity to autism spectrum disorders (ASDs) risk is debated and poorly understood. Some mothers of children with ASD have autoantibodies that react to fetal brain proteins, raising the possibility that a subset of ASD cases may be associated with a maternal antibody response during gestation. The mechanism by which the maternal immune system breaks tolerance has not been addressed. We hypothesized that the mechanism may involve decreased expression of the MET receptor tyrosine kinase, an ASD risk gene that also serves as a key negative regulator of immune responsiveness. In a sample of 365 mothers, including 202 mothers of children with ASD, the functional MET promoter variant rs1858830 C allele was strongly associated with the presence of an ASD-specific 37+73-kDa band pattern of maternal autoantibodies to fetal brain proteins (P=0.003). To determine the mechanism of this genetic association, we measured MET protein and cytokine production in freshly prepared peripheral blood mononuclear cells from 76 mothers of ASD and typically developing children. The MET rs1858830 C allele was significantly associated with MET protein expression (P=0.025). Moreover, decreased expression of the regulatory cytokine IL-10 was associated with both the MET gene C allele (P=0.001) and reduced MET protein levels (P=0.002). These results indicate genetic distinction among mothers who produce ASD-associated antibodies to fetal brain proteins, and suggest a potential mechanism for how a genetically determined decrease in MET protein production may lead to a reduction in immune regulation.

PMID: 22833194 [PubMed - indexed for MEDLINE]

rad001 ecdysone chir-258

A purpose-synthesised anti-fibrotic agent attenuates experimental kidney diseases in the rat.

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A purpose-synthesised anti-fibrotic agent attenuates experimental kidney diseases in the rat.

PLoS One. 2012;7(10):e47160

Authors: Gilbert RE, Zhang Y, Williams SJ, Zammit SC, Stapleton DI, Cox AJ, Krum H, Langham R, Kelly DJ

Abstract
BACKGROUND AND PURPOSE: Locally-active growth factors have been implicated in the pathogenesis of many diseases in which organ fibrosis is a characteristic feature. In the setting of chronic kidney disease (CKD), two such pro-fibrotic factors, transforming growth factor-? (TGF-?) and platelet-derived growth factor (PDGF) have emerged as lead potential targets for intervention. Given the incomplete organ protection afforded by blocking the actions of TGF-? or PDGF individually, we sought to determine whether an agent that inhibited the actions of both may have broader effects in ameliorating the key structural and functional abnormalities of CKD.
EXPERIMENTAL APPROACH: Accordingly, we studied the effects of a recently described, small molecule anti-fibrotic drug, 3-methoxy-4-propargyloxycinnamoyl anthranilate (FT011, Fibrotech Therapeutics, Australia), which should have these effects.
KEY RESULTS: In the in vitro setting, FT011 inhibited both TGF-?1 and PDGF-BB induced collagen production as well as PDGF-BB-mediated mesangial proliferation. Consistent with these in vitro actions, when studied in a robust model of non-diabetic kidney disease, the 5/6 nephrectomised rat, FT011 attenuated the decline in GFR, proteinuria and glomerulosclerosis (p<0.05 for all). Similarly, in the streptozotocin-diabetic Ren-2 rat, a model of advanced diabetic nephropathy, FT011 reduced albuminuria, glomerulosclerosis and tubulointerstitial fibrosis.
CONCLUSIONS AND IMPLICATIONS: Together these studies suggest that broadly antagonising growth factor actions, including those of TGF-?1 and PDGF-BB, has the potential to protect the kidney from progressive injury in both the diabetic and non-diabetic settings.

PMID: 23071743 [PubMed - indexed for MEDLINE]

dovitinib dna-pk coxinhibitors

Optimized outcomes for renal allografts with cold ischemic times of 20 h or greater.

Related Articles

Optimized outcomes for renal allografts with cold ischemic times of 20 h or greater.

Int Urol Nephrol. 2012 Oct;44(5):1417-23

Authors: Gallinat A, Paul A, Minor T, Treckmann JW, Molmenti EP, Witzke O, Sotiropoulos GC

Abstract
BACKGROUND: Prolonged cold ischemia time (CIT) has been associated with inferior graft survival in kidney transplantation (KT). The aim of this study was to evaluate the impact of prolonged CIT on short- and long-term outcomes and to determine the possible ways to optimize the use of these organs.
METHODS: All kidney transplants from April 2001 to December 2010 with CIT ? 20 h were considered. Donor and recipient data were analyzed with uni- and multivariate Cox proportional hazard analyses. Graft and patient survival were calculated using the Kaplan-Meier method.
RESULTS: One hundred and eighty-one patients were transplanted with 184 grafts. Median recipient age and waiting time on dialysis were 52.5 and 4.9 years, respectively. After a median follow-up of 4.9 years, 148 of 181 patients are alive, 143 of them with functioning grafts. One-, three, and five-year graft and patient survival rates were 90, 87, and 79 %, and 96, 91, and 85 %, respectively. Donor age (p < 0.0001), retransplantation (p = 0.0025), and induction therapy with interleukin-2 antagonists (p = 0.0487) were predictors of graft survival by univariate analysis. Donor age and retransplantation remained significant by multivariate analysis (p < 0.001 and p = 0.0046, respectively). Donor age (p = 0.0176) and creatinine level at 1-month post-KT (p = 0.0271) were predictors of patient survival by univariate analysis. Only donor age reached multivariate significance (p = 0.0464). The calculated donor age cut off was 60 years.
CONCLUSIONS: Satisfactory long-term kidney transplant outcomes in the setting of CIT ? 20 h can be achieved with grafts from donors <60 years in first-time recipients. Induction therapy should preferably be with an interleukin-2 antagonist.

PMID: 22752500 [PubMed - indexed for MEDLINE]

rad001 ecdysone chir-258

Activity of the Fibroblast Growth Factor Receptor Inhibitors Dovitinib (TKI258) and NVP-BGJ398 in Human Endometrial Cancer Cells.

Activity of the Fibroblast Growth Factor Receptor Inhibitors Dovitinib (TKI258) and NVP-BGJ398 in Human Endometrial Cancer Cells.

Mol Cancer Ther. 2013 Feb 26;

Authors: Konecny GE, Kolarova T, O'Brien NA, Winterhoff B, Yang G, Qi J, Qi Z, Venkatesan N, Ayala R, Luo T, Finn RS, Kristof J, Galderisi C, Graus Porta D, Anderson L, Shi MM, Yovine A, Slamon DJ

Abstract
The recent identification of activating fibroblast growth factor receptor 2 (FGFR2) mutations in endometrial cancer (EC) has generated an opportunity for a novel target-based therapy. Here we explore the therapeutic potential of two FGFR inhibitors, the multi-kinase inhibitor dovitinib (TKI258) and the more selective FGFR inhibitor NVP-BGJ398 for the treatment of EC. We examined the effects of both inhibitors on tumor cell growth, FGFR2 signaling, cell cycle and apoptosis using a panel of 20 molecularly characterized human EC cell lines. Anchorage independent growth was studied using soft agar assays. In vivo studies were conducted using EC xenograft models. Cell lines with activating FGFR2 mutations (S252W, N550K) were more sensitive to dovitinib or NVP-BGJ398 when compared to their FGFR2 wild-type counterparts (p=0.073 and p=0.021, respectively). Both agents inhibited FGFR2 signaling, induced cell cycle arrest and significantly increased apoptosis in FGFR2 mutant lines. In vitro, dovitinib and NVP-BGJ398 were both potent at inhibiting cell growth of FGFR2 mutant EC cells but the activity of dovitinib was less restricted to FGFR2 mutant lines when compared to NVP-BGJ398. In vivo, dovitinib and NVP-BGJ398 significantly inhibited the growth of FGFR2 mutated EC xenograft models. In addition, dovitinib showed significant antitumor activity in FGFR2 wild-type EC xenograft models including complete tumor regressions in a long term in vivo study. Dovitinib and NVP-BGJ398 warrant further clinical evaluation in patients with FGFR2 mutated EC. Dovitinib may have antitumor activity in EC beyond FGFR2 mutated cases and may permit greater flexibility in patient selection.

PMID: 23443805 [PubMed - as supplied by publisher]

dovitinib dna-pk coxinhibitors

Activity of the Fibroblast Growth Factor Receptor Inhibitors Dovitinib (TKI258) and NVP-BGJ398 in Human Endometrial Cancer Cells.

Activity of the Fibroblast Growth Factor Receptor Inhibitors Dovitinib (TKI258) and NVP-BGJ398 in Human Endometrial Cancer Cells.

Mol Cancer Ther. 2013 Feb 26;

Authors: Konecny GE, Kolarova T, O'Brien NA, Winterhoff B, Yang G, Qi J, Qi Z, Venkatesan N, Ayala R, Luo T, Finn RS, Kristof J, Galderisi C, Graus Porta D, Anderson L, Shi MM, Yovine A, Slamon DJ

Abstract
The recent identification of activating fibroblast growth factor receptor 2 (FGFR2) mutations in endometrial cancer (EC) has generated an opportunity for a novel target-based therapy. Here we explore the therapeutic potential of two FGFR inhibitors, the multi-kinase inhibitor dovitinib (TKI258) and the more selective FGFR inhibitor NVP-BGJ398 for the treatment of EC. We examined the effects of both inhibitors on tumor cell growth, FGFR2 signaling, cell cycle and apoptosis using a panel of 20 molecularly characterized human EC cell lines. Anchorage independent growth was studied using soft agar assays. In vivo studies were conducted using EC xenograft models. Cell lines with activating FGFR2 mutations (S252W, N550K) were more sensitive to dovitinib or NVP-BGJ398 when compared to their FGFR2 wild-type counterparts (p=0.073 and p=0.021, respectively). Both agents inhibited FGFR2 signaling, induced cell cycle arrest and significantly increased apoptosis in FGFR2 mutant lines. In vitro, dovitinib and NVP-BGJ398 were both potent at inhibiting cell growth of FGFR2 mutant EC cells but the activity of dovitinib was less restricted to FGFR2 mutant lines when compared to NVP-BGJ398. In vivo, dovitinib and NVP-BGJ398 significantly inhibited the growth of FGFR2 mutated EC xenograft models. In addition, dovitinib showed significant antitumor activity in FGFR2 wild-type EC xenograft models including complete tumor regressions in a long term in vivo study. Dovitinib and NVP-BGJ398 warrant further clinical evaluation in patients with FGFR2 mutated EC. Dovitinib may have antitumor activity in EC beyond FGFR2 mutated cases and may permit greater flexibility in patient selection.

PMID: 23443805 [PubMed - as supplied by publisher]

chir-258 dovitinib dna-pk

Single nucleotide polymorphisms and risk of recurrence of renal-cell carcinoma: a cohort study.

Related Articles

Single nucleotide polymorphisms and risk of recurrence of renal-cell carcinoma: a cohort study.

Lancet Oncol. 2013 Jan;14(1):81-7

Authors: Schutz FA, Pomerantz MM, Gray KP, Atkins MB, Rosenberg JE, Hirsch MS, McDermott DF, Lampron ME, Lee GS, Signoretti S, Kantoff PW, Freedman ML, Choueiri TK

Abstract
BACKGROUND: Germline genetic polymorphisms might affect the risk of recurrence in patients with localised renal-cell carcinoma. We investigated the association between genetic polymorphisms and recurrence of renal-cell carcinoma.
METHODS: We analysed germline DNA samples extracted from patients with localised renal-cell carcinoma treated at the Dana-Farber/Harvard Cancer Center (Boston, MA, USA). We selected a discovery cohort from a prospective database at the Dana-Farber/Harvard Cancer Center and selected a validation cohort from department records at the Brigham and Women's Hospital (Boston, MA, USA). We validated the findings from the discovery cohort in the validation cohort. We genotyped 70 genes involved in the pathogenesis of renal-cell carcinoma (including the VHL/HIF/VEGF and PI3K/AKT/mTOR pathways, and genes involved in immune regulation and metabolism) for single nucleotide polymorphisms. We assessed the association between genotype and recurrence-free survival, adjusted for baseline characteristics, with the Cox proportional hazards model, the Kaplan-Meier method, and the log-rank test. We used a false discovery rate q value to adjust for multiple comparisons.
FINDINGS: We included 554 patients (403 in the discovery cohort and 151 in the validation cohort). We successfully genotyped 290 single nucleotide polymorphisms in the discovery cohort, but excluded five because they did not have a variant group for comparison. The polymorphism rs11762213, which causes a synonymous aminoacid change in MET (144G?A, located in exon 2), was associated with recurrence-free survival. Patients with one or two copies of the minor (risk) allele had an increased risk of recurrence or death (hazard ratio [HR] 1�86, 95% CI 1�17-2�95; p=0�0084) in multivariate analysis. Median recurrence-free survival for carriers of the risk allele was 19 months (95% CI 9-not reached) versus 50 months (95% CI 37-75) for patients without the risk allele. In the validation cohort the HR was 2�45 (95% CI 1�01-5�95; p=0�048).
INTERPRETATION: Patients with localised renal-cell carcinoma and the MET polymorphism rs11762213 might have an increased risk of recurrence after nephrectomy. If these results are further validated in a similar population, they could be incorporated into future prognostic instruments, potentially aiding the design of adjuvant clinical trials of MET inhibitors and management of renal-cell carcinoma.
FUNDING: Conquer Cancer Foundation and American Society of Clinical Oncology (Career Development Award); The Trust Family Research Fund for Kidney Cancer; US National Institutes of Health, National Cancer Institute Kidney Cancer Specialized Program of Research Excellence.

PMID: 23219378 [PubMed - indexed for MEDLINE]

dovitinib dna-pk coxinhibitors

Systemic treatment for hereditary cancers: a 2012 update.

Systemic treatment for hereditary cancers: a 2012 update.

Hered Cancer Clin Pract. 2013 Apr 1;11(1):2

Authors: Imyanitov EN, Byrski T

Abstract
: The history of specific therapy for hereditary tumors dates back to mid 1980s and involves a number of reports demonstrating regression of familial colon polyps upon administration of sulindac. Virtually no clinical studies on other hereditary cancer types were available until the year 2009, when Byrski et al. presented the data on unprecedented sensitivity of BRCA1-associated breast malignancies to cisplatin. This breakthrough has revived interest to the treatment of cancer in germ-line mutation carriers. Recent trials and clinical observations have confirmed the efficacy of platinating agents and PARP inhibitors in BRCA1/2-driven breast, ovarian and pancreatic carcinomas. Pegylated liposomal doxorubicin may be considered as a promising treatment option for BRCA1/2-related ovarian cancer after the failure of platinum-containing therapy. Several novel drugs have been recently introduced in the management of rare familial tumor syndromes. Vandetanib, a low-molecular weight RET kinase inhibitor, demonstrated substantial efficacy in the treatment of hereditary and sporadic medullary thyroid cancer. Vismodegib, an inhibitor of SMO oncoprotein, caused regression of basal-cell carcinomas in patients with Gorlin syndrome. Down-regulation of mTOR kinase by everolimus has been successfully used for the therapy of subependymal giant-cell astrocytomas in patients with tuberous sclerosis. The achievements in the prevention, diagnostics and treatment of hereditary cancers may serve as an excellent example of triumph of translational medicine.Graphical Abstract: <!-- [INSERT GRAPHICAL ABSTRACT TEXT HERE] -->

PMID: 23548133 [PubMed - as supplied by publisher]

c-met inhibitors zm-447439 rad001

Activity of the Fibroblast Growth Factor Receptor Inhibitors Dovitinib (TKI258) and NVP-BGJ398 in Human Endometrial Cancer Cells.

Activity of the Fibroblast Growth Factor Receptor Inhibitors Dovitinib (TKI258) and NVP-BGJ398 in Human Endometrial Cancer Cells.

Mol Cancer Ther. 2013 Feb 26;

Authors: Konecny GE, Kolarova T, O'Brien NA, Winterhoff B, Yang G, Qi J, Qi Z, Venkatesan N, Ayala R, Luo T, Finn RS, Kristof J, Galderisi C, Graus Porta D, Anderson L, Shi MM, Yovine A, Slamon DJ

Abstract
The recent identification of activating fibroblast growth factor receptor 2 (FGFR2) mutations in endometrial cancer (EC) has generated an opportunity for a novel target-based therapy. Here we explore the therapeutic potential of two FGFR inhibitors, the multi-kinase inhibitor dovitinib (TKI258) and the more selective FGFR inhibitor NVP-BGJ398 for the treatment of EC. We examined the effects of both inhibitors on tumor cell growth, FGFR2 signaling, cell cycle and apoptosis using a panel of 20 molecularly characterized human EC cell lines. Anchorage independent growth was studied using soft agar assays. In vivo studies were conducted using EC xenograft models. Cell lines with activating FGFR2 mutations (S252W, N550K) were more sensitive to dovitinib or NVP-BGJ398 when compared to their FGFR2 wild-type counterparts (p=0.073 and p=0.021, respectively). Both agents inhibited FGFR2 signaling, induced cell cycle arrest and significantly increased apoptosis in FGFR2 mutant lines. In vitro, dovitinib and NVP-BGJ398 were both potent at inhibiting cell growth of FGFR2 mutant EC cells but the activity of dovitinib was less restricted to FGFR2 mutant lines when compared to NVP-BGJ398. In vivo, dovitinib and NVP-BGJ398 significantly inhibited the growth of FGFR2 mutated EC xenograft models. In addition, dovitinib showed significant antitumor activity in FGFR2 wild-type EC xenograft models including complete tumor regressions in a long term in vivo study. Dovitinib and NVP-BGJ398 warrant further clinical evaluation in patients with FGFR2 mutated EC. Dovitinib may have antitumor activity in EC beyond FGFR2 mutated cases and may permit greater flexibility in patient selection.

PMID: 23443805 [PubMed - as supplied by publisher]

c-met inhibitors zm-447439 rad001

Activity of the Fibroblast Growth Factor Receptor Inhibitors Dovitinib (TKI258) and NVP-BGJ398 in Human Endometrial Cancer Cells.

Activity of the Fibroblast Growth Factor Receptor Inhibitors Dovitinib (TKI258) and NVP-BGJ398 in Human Endometrial Cancer Cells.

Mol Cancer Ther. 2013 Feb 26;

Authors: Konecny GE, Kolarova T, O'Brien NA, Winterhoff B, Yang G, Qi J, Qi Z, Venkatesan N, Ayala R, Luo T, Finn RS, Kristof J, Galderisi C, Graus Porta D, Anderson L, Shi MM, Yovine A, Slamon DJ

Abstract
The recent identification of activating fibroblast growth factor receptor 2 (FGFR2) mutations in endometrial cancer (EC) has generated an opportunity for a novel target-based therapy. Here we explore the therapeutic potential of two FGFR inhibitors, the multi-kinase inhibitor dovitinib (TKI258) and the more selective FGFR inhibitor NVP-BGJ398 for the treatment of EC. We examined the effects of both inhibitors on tumor cell growth, FGFR2 signaling, cell cycle and apoptosis using a panel of 20 molecularly characterized human EC cell lines. Anchorage independent growth was studied using soft agar assays. In vivo studies were conducted using EC xenograft models. Cell lines with activating FGFR2 mutations (S252W, N550K) were more sensitive to dovitinib or NVP-BGJ398 when compared to their FGFR2 wild-type counterparts (p=0.073 and p=0.021, respectively). Both agents inhibited FGFR2 signaling, induced cell cycle arrest and significantly increased apoptosis in FGFR2 mutant lines. In vitro, dovitinib and NVP-BGJ398 were both potent at inhibiting cell growth of FGFR2 mutant EC cells but the activity of dovitinib was less restricted to FGFR2 mutant lines when compared to NVP-BGJ398. In vivo, dovitinib and NVP-BGJ398 significantly inhibited the growth of FGFR2 mutated EC xenograft models. In addition, dovitinib showed significant antitumor activity in FGFR2 wild-type EC xenograft models including complete tumor regressions in a long term in vivo study. Dovitinib and NVP-BGJ398 warrant further clinical evaluation in patients with FGFR2 mutated EC. Dovitinib may have antitumor activity in EC beyond FGFR2 mutated cases and may permit greater flexibility in patient selection.

PMID: 23443805 [PubMed - as supplied by publisher]

ecdysone chir-258 dovitinib

Preclinical evaluation of combined TKI-258 and RAD001 in hepatocellular carcinoma.

Related Articles

Preclinical evaluation of combined TKI-258 and RAD001 in hepatocellular carcinoma.

Cancer Chemother Pharmacol. 2013 Apr 2;

Authors: Chan SL, Wong CH, Lau CP, Zhou Q, Hui CW, Lui VW, Ma BB, Chan AT, Yeo W

Abstract
PURPOSE: RAD001 targets at the mammalian target of rapamycin (mTOR), while TKI-258 is a potent tyrosine kinase inhibitor targeting at fibroblast growth factor receptor, vascular endothelial growth factor receptor, platelet-derived growth factor receptor and c-kit. We aim to study the activity of combined RAD001 and TKI-258 in cell lines and xenograft model of hepatocellular carcinoma (HCC), with reference to the parallel and upstream pathways of Akt-mTOR axis. METHODS: A panel of 4 human HCC cell lines HepG2, Hep3B, PLC/PRF/5 and Huh7 and the Hep3B-derived xenograft were treated with TKI-258 or/and RAD001, respectively. Related mechanistic studies (including apoptosis and angiogenesis) were conducted. RESULTS: There was an enhanced increase in suppression of cell proliferation with combined TKI-258 and RAD001 compared with either drug alone. The combination could significantly suppress the phosphorylation of mTOR, MEK1/2 and p38 MAPK. Although the addition of the TKI258 only slightly suppressed the phosphorylation of AKT induced by RAD001, the pi-mTOR and its downstream signaling pathways including pi-p70S6K, pi-S6 and pi-4EBP1 were lowered in the combination. In Hep3B-derived xenograft, TKI-258 and RAD001 had shown an enhanced inhibition of tumor growth without impact on the weight of animals. There was a reduction in microvessel density in the xenograft with the combination, which indicated an enhanced inhibition on angiogenesis. Pro-caspases-3 and PARP cleavage were slightly detected at 48�h after treatment, suggesting that the combination mainly increased the cytostatic arrest ability. CONCLUSIONS: The combination of RAD001 and TKI-258 was active in HCC via inhibition of both mTOR-mediated signaling and its parallel pathways.

PMID: 23546591 [PubMed - as supplied by publisher]

zm-447439 rad001 ecdysone

Antibody targeting of anaplastic lymphoma kinase induces cytotoxicity of human neuroblastoma.

Related Articles

Antibody targeting of anaplastic lymphoma kinase induces cytotoxicity of human neuroblastoma.

Oncogene. 2012 Nov 15;31(46):4859-67

Authors: Carpenter EL, Haglund EA, Mace EM, Deng D, Martinez D, Wood AC, Chow AK, Weiser DA, Belcastro LT, Winter C, Bresler SC, Vigny M, Mazot P, Asgharzadeh S, Seeger RC, Zhao H, Guo R, Christensen JG, Orange JS, Pawel BR, Lemmon MA, Moss� YP

Abstract
Anaplastic lymphoma kinase (ALK) is a receptor tyrosine kinase aberrantly expressed in neuroblastoma, a devastating pediatric cancer of the sympathetic nervous system. Germline and somatically acquired ALK aberrations induce increased autophosphorylation, constitutive ALK activation and increased downstream signaling. Thus, ALK is a tractable therapeutic target in neuroblastoma, likely to be susceptible to both small-molecule tyrosine kinase inhibitors and therapeutic antibodies-as has been shown for other receptor tyrosine kinases in malignancies such as breast and lung cancer. Small-molecule inhibitors of ALK are currently being studied in the clinic, but common ALK mutations in neuroblastoma appear to show de novo insensitivity, arguing that complementary therapeutic approaches must be developed. We therefore hypothesized that antibody targeting of ALK may be a relevant strategy for the majority of neuroblastoma patients likely to have ALK-positive tumors. We show here that an antagonistic ALK antibody inhibits cell growth and induces in vitro antibody-dependent cellular cytotoxicity of human neuroblastoma-derived cell lines. Cytotoxicity was induced in cell lines harboring either wild type or mutated forms of ALK. Treatment of neuroblastoma cells with the dual Met/ALK inhibitor crizotinib sensitized cells to antibody-induced growth inhibition by promoting cell surface accumulation of ALK and thus increasing the accessibility of antigen for antibody binding. These data support the concept of ALK-targeted immunotherapy as a highly promising therapeutic strategy for neuroblastomas with mutated or wild-type ALK.

PMID: 22266870 [PubMed - indexed for MEDLINE]

zm-447439 rad001 ecdysone

Cytomegalovirus-Positive Corneal Stromal Edema With Keratic Precipitates After Penetrating Keratoplasty: A Case-Control Study.

Cytomegalovirus-Positive Corneal Stromal Edema With Keratic Precipitates After Penetrating Keratoplasty: A Case-Control Study.

Cornea. 2013 Mar 27;

Authors: Chee SP, Jap A, Wen Ling EC, Ti SE

Abstract
PURPOSE:: To identify differences between cytomegalovirus (CMV)-positive and CMV-negative eyes presenting as suspected endothelial graft rejection after penetrating keratoplasty (PK). METHODS:: A retrospective consecutive case-control series. Aqueous humor samples of all eyes with corneal stromal edema and keratic precipitates (KPs) after PK, seen at the Singapore National Eye Centre from 2007 to 2010, were analyzed for CMV DNA by polymerase chain reaction. Their charts were reviewed for demographic data, medical and ocular history, best-corrected visual acuity, intraocular pressure, anterior segment clinical findings, and therapy. RESULTS:: Of 11 eligible eyes (11 patients), 7 were CMV positive. All eyes were negative for herpes simplex virus and varicella zoster virus. The 2 groups were similar in age, gender, and previous ocular surgery. The main differences were the presence of extensive heavily pigmented KPs, Descemet membrane folds, and the absence of vascularization of the donor in CMV-positive eyes (100% vs. 0%, P = 0.003, Fisher exact test). All the CMV-positive eyes were treated with ganciclovir (5 systemic, 2 topical), and the control eyes received immunosuppression. However, all the grafts failed. Best-corrected visual acuity at the last visit was worse than 20/400 in all except 1 control eye, which had a follow-up of 30 months. CONCLUSIONS:: There is a high prevalence of CMV infection in eyes that develop corneal stromal edema with KPs after PK. Heavy endothelial pigmentation, Descemet membrane folds, and the absence of donor vascularization may aid in the diagnosis of CMV in the event that aqueous analysis is not possible.

PMID: 23538617 [PubMed - as supplied by publisher]

rad001 ecdysone chir-258

Optimizing megakaryocyte polyploidization by targeting multiple pathways of cytokinesis.

Related Articles

Optimizing megakaryocyte polyploidization by targeting multiple pathways of cytokinesis.

Transfusion. 2012 Nov;52(11):2406-13

Authors: Avanzi MP, Chen A, He W, Mitchell WB

Abstract
BACKGROUND: Large-scale in vitro production of platelets (PLTs) from cord blood stem cells is one goal of stem cell research. One step toward this goal will be to produce polyploid megakaryocytes capable of releasing high numbers of PLTs. Megakaryocyte polyploidization requires distinct cytoskeletal and cellular mechanisms, including actin polymerization, myosin activation, microtubule formation, and increased DNA production. In this study we variably combined inhibition of these principal mechanisms of cytokinesis with the goal of driving polyploidization in megakaryocytes.
STUDY DESIGN AND METHODS: Megakaryocytes were derived from umbilical cord blood and cultured with reagents that inhibit distinct mechanisms of cytokinesis: Rho-Rock inhibitor (RRI), Src inhibitor (SI), nicotinamide (NIC), aurora B inhibitor (ABI), and myosin light chain kinase inhibitor (MLCKI). Combinations of reagents were used to determine their interactions and to maximize megakaryocyte ploidy.
RESULTS: Treatment with RRI, NIC, SI, and ABI, but not with MLCKI, increased the final ploidy and RRI was the most effective single reagent. RRI and MLCKI, both inhibitors of MLC activation, resulted in opposite ploidy outcomes. Combinations of reagents also increased ploidy and the use of NIC, SI, and ABI was as effective as RRI alone. Addition of MLCKI to NIC, SI, and ABI reached the highest level of polyploidization.
CONCLUSION: Megakaryocyte polyploidization results from modulation of a combination of distinct cytokinesis pathways. Reagents targeting distinct cytoskeletal pathways produced additive effects in final megakaryocyte ploidy. The RRI, however, showed no additive effect but produced a high final ploidy due to overlapping inhibition of multiple cytokinesis pathways.

PMID: 22612069 [PubMed - indexed for MEDLINE]

rad001 ecdysone chir-258

Optimizing megakaryocyte polyploidization by targeting multiple pathways of cytokinesis.

Related Articles

Optimizing megakaryocyte polyploidization by targeting multiple pathways of cytokinesis.

Transfusion. 2012 Nov;52(11):2406-13

Authors: Avanzi MP, Chen A, He W, Mitchell WB

Abstract
BACKGROUND: Large-scale in vitro production of platelets (PLTs) from cord blood stem cells is one goal of stem cell research. One step toward this goal will be to produce polyploid megakaryocytes capable of releasing high numbers of PLTs. Megakaryocyte polyploidization requires distinct cytoskeletal and cellular mechanisms, including actin polymerization, myosin activation, microtubule formation, and increased DNA production. In this study we variably combined inhibition of these principal mechanisms of cytokinesis with the goal of driving polyploidization in megakaryocytes.
STUDY DESIGN AND METHODS: Megakaryocytes were derived from umbilical cord blood and cultured with reagents that inhibit distinct mechanisms of cytokinesis: Rho-Rock inhibitor (RRI), Src inhibitor (SI), nicotinamide (NIC), aurora B inhibitor (ABI), and myosin light chain kinase inhibitor (MLCKI). Combinations of reagents were used to determine their interactions and to maximize megakaryocyte ploidy.
RESULTS: Treatment with RRI, NIC, SI, and ABI, but not with MLCKI, increased the final ploidy and RRI was the most effective single reagent. RRI and MLCKI, both inhibitors of MLC activation, resulted in opposite ploidy outcomes. Combinations of reagents also increased ploidy and the use of NIC, SI, and ABI was as effective as RRI alone. Addition of MLCKI to NIC, SI, and ABI reached the highest level of polyploidization.
CONCLUSION: Megakaryocyte polyploidization results from modulation of a combination of distinct cytokinesis pathways. Reagents targeting distinct cytoskeletal pathways produced additive effects in final megakaryocyte ploidy. The RRI, however, showed no additive effect but produced a high final ploidy due to overlapping inhibition of multiple cytokinesis pathways.

PMID: 22612069 [PubMed - indexed for MEDLINE]

chir-258 dovitinib dna-pk

Optimizing megakaryocyte polyploidization by targeting multiple pathways of cytokinesis.

Related Articles

Optimizing megakaryocyte polyploidization by targeting multiple pathways of cytokinesis.

Transfusion. 2012 Nov;52(11):2406-13

Authors: Avanzi MP, Chen A, He W, Mitchell WB

Abstract
BACKGROUND: Large-scale in vitro production of platelets (PLTs) from cord blood stem cells is one goal of stem cell research. One step toward this goal will be to produce polyploid megakaryocytes capable of releasing high numbers of PLTs. Megakaryocyte polyploidization requires distinct cytoskeletal and cellular mechanisms, including actin polymerization, myosin activation, microtubule formation, and increased DNA production. In this study we variably combined inhibition of these principal mechanisms of cytokinesis with the goal of driving polyploidization in megakaryocytes.
STUDY DESIGN AND METHODS: Megakaryocytes were derived from umbilical cord blood and cultured with reagents that inhibit distinct mechanisms of cytokinesis: Rho-Rock inhibitor (RRI), Src inhibitor (SI), nicotinamide (NIC), aurora B inhibitor (ABI), and myosin light chain kinase inhibitor (MLCKI). Combinations of reagents were used to determine their interactions and to maximize megakaryocyte ploidy.
RESULTS: Treatment with RRI, NIC, SI, and ABI, but not with MLCKI, increased the final ploidy and RRI was the most effective single reagent. RRI and MLCKI, both inhibitors of MLC activation, resulted in opposite ploidy outcomes. Combinations of reagents also increased ploidy and the use of NIC, SI, and ABI was as effective as RRI alone. Addition of MLCKI to NIC, SI, and ABI reached the highest level of polyploidization.
CONCLUSION: Megakaryocyte polyploidization results from modulation of a combination of distinct cytokinesis pathways. Reagents targeting distinct cytoskeletal pathways produced additive effects in final megakaryocyte ploidy. The RRI, however, showed no additive effect but produced a high final ploidy due to overlapping inhibition of multiple cytokinesis pathways.

PMID: 22612069 [PubMed - indexed for MEDLINE]

zm-447439 rad001 ecdysone

Nuclear receptors HR96 and Ultraspiracle from the fall armyworm (Spodoptera frugiperda), developmental expression and induction by xenobiotics.

Nuclear receptors HR96 and Ultraspiracle from the fall armyworm (Spodoptera frugiperda), developmental expression and induction by xenobiotics.

J Insect Physiol. 2013 Mar 19;

Authors: Giraudo M, Audant P, Feyereisen R, Goff GL

Abstract
The fall armyworm Spodoptera frugiperda is a major polyphagous pest in agriculture and little is known on how this insect can adapt to the diverse and potentially toxic plant allelochemicals that they ingest or to insecticides. To investigate the involvement of nuclear receptors in the response of Spodoptera frugiperda to its chemical environment, we cloned SfHR96, a nuclear receptor orthologous to the mammalian xenobiotic receptors, pregnane X receptor (PXR) and constitutive androstane receptor (CAR). We also cloned Ultraspiracle (USP), the ortholog of retinoid X receptor (RXR) that serves as partner of dimerization of PXR and CAR. Cloning of SfUSP revealed the presence of two isoforms, SfUSP-1 and SfUSP-2 in this species, that differ in their N-terminal region. The expression of these receptors as well as the ecdysone receptor was studied during specific steps of development in different tissues. SfHR96 was constitutively expressed in larval midgut, fat body and Malpighian tubules throughout the last two instars and pupal stage, as well as in Sf9 cells. EcR and SfUSP-2 showed peaks of expression before larval moults and during metamorphosis, whereas SfUSP-1 was mainly expressed in the pre-pupal stage. Receptor induction was followed after exposure of larvae or cells to eleven chemicals compounds. SfHR96 was not inducible by the tested compounds. EcR was significantly induced by the 20- hydroxyecdysone agonist, methoxyfenozide, and SfUSP showed an increase expression when exposed to the juvenile hormone analog, methoprene. The cloning of these nuclear receptors is a first step in the understanding of the important capacities of adaptation of this insect pest.

PMID: 23523827 [PubMed - as supplied by publisher]

coxinhibitors c-met inhibitors zm-447439

Image-based high-throughput screening for inhibitors of angiogenesis.

Related Articles

Image-based high-throughput screening for inhibitors of angiogenesis.

Methods Mol Biol. 2013;931:139-51

Authors: Evensen L, Link W, Lorens JB

Abstract
Automated multicolor fluorescence microscopy facilitates high-throughput quantitation of cellular parameters of complex, organotypic systems. In vitro co-cultured vascular cells form capillary-like networks that model facets of angiogenesis, making it an attractive alternative for anti-angiogenic drug discovery. We have adapted this angiogenesis assay system to a high-throughput format to enable automated image-based high-throughput screening of live primary human vascular cell co-cultures with chemical libraries for anti-angiogenic drug discovery. Protocols are described for setup of a fluorescence-based co-culture assay, live cell image acquisition, image analysis of morphological parameters, and screening data handling.

PMID: 23027002 [PubMed - indexed for MEDLINE]

dna-pk coxinhibitors c-met inhibitors

[Meloxicam-induced colitis revealed by acute abdominal pain].

[Meloxicam-induced colitis revealed by acute abdominal pain].

Ann Pharm Fr. 2013 Mar;71(2):119-22

Authors: Seddik H, Rabhi M

Abstract
Whether intestinal toxicity of preferential or selective COX-2�inhibitors is reduced compared with that of standard NSAIDs is controversial. A 26-year-old woman presented with acute abdominal pain and bloody diarrhoea a few days after beginning meloxicam treatment. Endoscopic examination of the colon showed erythematous and ulcerative lesions involving 15cm of the left colon. No aetiology has been found for colitis. Diarrhea disappeared 1week after meloxicam was stopped. Total colonoscopy 3�months and 2�years later was normal. The role of meloxicam in the etiology of colitis was considered plausible. This report and a few other cases in the literature suggest that cyclooxygenase-2�selective non-steroidal anti-inflammatory drug inhibitor toxicity should be investigated in case of unexplained acute colitis.

PMID: 23537413 [PubMed - in process]

dna-pk coxinhibitors c-met inhibitors

Effects of Prostaglandins and COX Inhibiting Drugs on Skeletal Muscle Adaptations to Exercise.

Effects of Prostaglandins and COX Inhibiting Drugs on Skeletal Muscle Adaptations to Exercise.

J Appl Physiol. 2013 Mar 28;

Authors: Trappe TA, Liu SZ

Abstract
It has been ~40 years since the discovery that prostaglandins are produced by exercising skeletal muscle, and since the discovery that inhibition of prostaglandin synthesis is the mechanism of action of what are now known as cyclooxygenase (COX)-inhibiting drugs. Since that time, it has been established that prostaglandins are made during and after aerobic and resistance exercise and have a potent paracrine/autocrine effect on muscle metabolism. Consequently, it has also been determined that orally consumed doses of COX-inhibitors can profoundly influence muscle prostaglandin synthesis, muscle protein metabolism, and numerous other cellular processes that regulate muscle adaptations to exercise loading. Although data from acute human exercise studies, as well as animal and cell culture data would predict regular consumption of a COX-inhibitor during exercise training would dampen the typical muscle adaptations, the chronic data do not support this conjecture. From the studies in young and older individuals lasting from 1.5-4 months, no interfering effects of COX-inhibitors on muscle adaptations to resistance exercise training have been noted. In fact, in older individuals a substantial enhancement of muscle mass and strength has been observed. The collective findings of the prostaglandin/COX pathway regulation of skeletal muscle responses and adaptations to exercise are compelling. Considering the discoveries in other areas of COX regulation of health and disease there is certainly an interesting future of investigation in this re-emerging area, especially as it pertains to older individuals and the condition of sarcopenia, as well as exercise training and performance of individuals of all ages.

PMID: 23539318 [PubMed - as supplied by publisher]

ecdysone chir-258 dovitinib

Optimizing megakaryocyte polyploidization by targeting multiple pathways of cytokinesis.

Related Articles

Optimizing megakaryocyte polyploidization by targeting multiple pathways of cytokinesis.

Transfusion. 2012 Nov;52(11):2406-13

Authors: Avanzi MP, Chen A, He W, Mitchell WB

Abstract
BACKGROUND: Large-scale in vitro production of platelets (PLTs) from cord blood stem cells is one goal of stem cell research. One step toward this goal will be to produce polyploid megakaryocytes capable of releasing high numbers of PLTs. Megakaryocyte polyploidization requires distinct cytoskeletal and cellular mechanisms, including actin polymerization, myosin activation, microtubule formation, and increased DNA production. In this study we variably combined inhibition of these principal mechanisms of cytokinesis with the goal of driving polyploidization in megakaryocytes.
STUDY DESIGN AND METHODS: Megakaryocytes were derived from umbilical cord blood and cultured with reagents that inhibit distinct mechanisms of cytokinesis: Rho-Rock inhibitor (RRI), Src inhibitor (SI), nicotinamide (NIC), aurora B inhibitor (ABI), and myosin light chain kinase inhibitor (MLCKI). Combinations of reagents were used to determine their interactions and to maximize megakaryocyte ploidy.
RESULTS: Treatment with RRI, NIC, SI, and ABI, but not with MLCKI, increased the final ploidy and RRI was the most effective single reagent. RRI and MLCKI, both inhibitors of MLC activation, resulted in opposite ploidy outcomes. Combinations of reagents also increased ploidy and the use of NIC, SI, and ABI was as effective as RRI alone. Addition of MLCKI to NIC, SI, and ABI reached the highest level of polyploidization.
CONCLUSION: Megakaryocyte polyploidization results from modulation of a combination of distinct cytokinesis pathways. Reagents targeting distinct cytoskeletal pathways produced additive effects in final megakaryocyte ploidy. The RRI, however, showed no additive effect but produced a high final ploidy due to overlapping inhibition of multiple cytokinesis pathways.

PMID: 22612069 [PubMed - indexed for MEDLINE]

chir-258 dovitinib dna-pk

Spirocyclic �-Site Amyloid Precursor Protein Cleaving Enzyme 1 (BACE1) Inhibitors: From Hit to Lowering of Cerebrospinal Fluid (CSF) Amyloid Beta in a Higher Species.

Spirocyclic �-Site Amyloid Precursor Protein Cleaving Enzyme 1 (BACE1) Inhibitors: From Hit to Lowering of Cerebrospinal Fluid (CSF) Amyloid Beta in a Higher Species.

J Med Chem. 2013 Mar 28;

Authors: Hunt KW, Cook AW, Watts RJ, Clark CT, Vigers G, Smith D, Metcalf AT, Gunawardana IW, Burkard M, Cox AA, Geck-Do M, Dutcher D, Thomas AA, Rana S, Kallan NC, Delisle RK, Rizzi JP, Regal K, Sammond D, Groneberg R, Siu M, Purkey H, Lyssikatos JP, Marlow A, Liu X, Tang TP

Abstract
A hallmark of Alzheimer's disease is the brain deposition of amyloid beta (A�), a peptide of 36-43 amino acids that is likely a primary driver of neurodegeneration. A� is produced by the sequential cleavage of APP by BACE1 and ?-secretase; therefore, inhibition of BACE1 represents an attractive therapeutic target to slow or prevent Alzheimer's disease. Herein we describe BACE1 inhibitors with limited molecular flexibility and molecular weight that decrease CSF A� in vivo, despite efflux. Starting with spirocycle 1a, we explore structure activity relationships of core changes, P3 moieties and Asp binding functional groups in order to optimize BACE1 affinity, cathepsin D selectivity, and blood-brain barrier (BBB) penetration. Using wild type guinea pig and rat, we demonstrate a PK/PD relationship between free drug concentrations in the brain and CSF A� lowering. Optimization of brain exposure led to the discovery of (R)-50 which reduced CSF A� in rodents and in monkey.

PMID: 23537249 [PubMed - as supplied by publisher]

dna-pk coxinhibitors c-met inhibitors

Anti-inflammatory and antioxidant activities of constituents isolated from Pueraria lobata roots.

Related Articles

Anti-inflammatory and antioxidant activities of constituents isolated from Pueraria lobata roots.

Arch Pharm Res. 2012 May;35(5):823-37

Authors: Jin SE, Son YK, Min BS, Jung HA, Choi JS

Abstract
In order to evaluate the anti-inflammatory and antioxidant activities of Pueraria lobata roots and its active components, in vitro inhibitory activities against lipopolysaccharide (LPS)-induced nitric oxide (NO) production, inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) protein expression, and tert-butylhydroperoxide (t-BHP)-induced reactive oxygen species (ROS) generation in RAW 264.7 cells, as well as in vitro scavenging activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH), peroxynitrite (ONOO(-)), nitric oxide (NO�), superoxide anion (�O(2)(-)) and total ROS, and inhibitory activities against ONOO(-)-mediated tyrosine nitration, were determined. Repeated column chromatography was performed to isolate four known compounds from the anti-inflammatory and antioxidant EtOAc fraction: daidzein; genistein; puerarin; (+)-puerarol B-2-O-glucopyranoside; four known compounds from the anti-inflammatory n-hexane fraction: lupenone; lupeol; puerarol; coumestrol; seven known compounds from the antioxidant n-BuOH fraction: allantoin; 3'-hydroxypuerarin; daidzein 8-C-apiosyl-(1?6)-glucoside; puerarin; genistin; 3'-methoxypuerarin; daidzin. Among these compounds, lupenone and lupeol reduced NO production, as well as iNOS and COX-2 protein levels in LPS-stimulated RAW 264.7 cells. Furthermore, lupeol showed significant inhibitory activity against intracellular ROS generation by t-BHP. Meanwhile, 3'-hydroxypuerarin showed marked ONOO(-), NO�, total ROS scavenging activities, and weak �O(2)(-) scavenging activity, while 3'-methoxypuerarin showed ONOO(-) scavenging activity and weak NO� and O(2)(-) scavenging activities, suggesting that existence of the 3'-hydroxyl group in puerarin plays an important role in the scavenging of ONOO(-), NO�, and total ROS, as well as inhibiting the ONOO(-)-mediated tyrosine nitration mechanism. These results indicate that P. lobata roots and its constituents may be a useful therapeutic and preventive approach to various inflammatory diseases and oxidative stress-related disease.

PMID: 22644850 [PubMed - indexed for MEDLINE]

chir-258 dovitinib dna-pk

Nuclear receptors HR96 and Ultraspiracle from the fall armyworm (Spodoptera frugiperda), developmental expression and induction by xenobiotics.

Nuclear receptors HR96 and Ultraspiracle from the fall armyworm (Spodoptera frugiperda), developmental expression and induction by xenobiotics.

J Insect Physiol. 2013 Mar 19;

Authors: Giraudo M, Audant P, Feyereisen R, Goff GL

Abstract
The fall armyworm Spodoptera frugiperda is a major polyphagous pest in agriculture and little is known on how this insect can adapt to the diverse and potentially toxic plant allelochemicals that they ingest or to insecticides. To investigate the involvement of nuclear receptors in the response of Spodoptera frugiperda to its chemical environment, we cloned SfHR96, a nuclear receptor orthologous to the mammalian xenobiotic receptors, pregnane X receptor (PXR) and constitutive androstane receptor (CAR). We also cloned Ultraspiracle (USP), the ortholog of retinoid X receptor (RXR) that serves as partner of dimerization of PXR and CAR. Cloning of SfUSP revealed the presence of two isoforms, SfUSP-1 and SfUSP-2 in this species, that differ in their N-terminal region. The expression of these receptors as well as the ecdysone receptor was studied during specific steps of development in different tissues. SfHR96 was constitutively expressed in larval midgut, fat body and Malpighian tubules throughout the last two instars and pupal stage, as well as in Sf9 cells. EcR and SfUSP-2 showed peaks of expression before larval moults and during metamorphosis, whereas SfUSP-1 was mainly expressed in the pre-pupal stage. Receptor induction was followed after exposure of larvae or cells to eleven chemicals compounds. SfHR96 was not inducible by the tested compounds. EcR was significantly induced by the 20- hydroxyecdysone agonist, methoxyfenozide, and SfUSP showed an increase expression when exposed to the juvenile hormone analog, methoprene. The cloning of these nuclear receptors is a first step in the understanding of the important capacities of adaptation of this insect pest.

PMID: 23523827 [PubMed - as supplied by publisher]

zm-447439 rad001 ecdysone

Role of prostaglandin receptor EP2 in the regulations of cancer cell proliferation, invasion, and inflammation.

Related Articles

Role of prostaglandin receptor EP2 in the regulations of cancer cell proliferation, invasion, and inflammation.

J Pharmacol Exp Ther. 2013 Feb;344(2):360-7

Authors: Jiang J, Dingledine R

Abstract
Population studies, preclinical, and clinical trials suggest a role for cyclooxygenase-2 (COX-2, PTGS2) in tumor formation and progression. The downstream prostanoid receptor signaling pathways involved in tumorigenesis are poorly understood, although prostaglandin E2 (PGE(2)), a major COX-2 metabolite which is usually upregulated in the involved tissues, presumably plays important roles in tumor biology. Taking advantage of our recently identified novel selective antagonist for the EP2 (PTGER2) subtype of PGE(2) receptor, we demonstrated that EP2 receptor activation could promote prostate cancer cell growth and invasion in vitro, accompanied by upregulation of the tumor-promoting inflammatory cytokines, such as IL-1? and IL-6. Our results suggest the involvement of prostaglandin receptor EP2 in cancer cell proliferation and invasion possibly via its inflammatory actions, and indicate that selective blockade of the PGE(2)-EP2 signaling pathway via small molecule antagonists might represent a novel therapy for tumorigenesis.

PMID: 23192657 [PubMed - indexed for MEDLINE]

c-met inhibitors zm-447439 rad001

Polycystic kidney disease: new horizons and therapeutic frontiers.

Polycystic kidney disease: new horizons and therapeutic frontiers.

Minerva Urol Nefrol. 2013 Mar;65(1):61-8

Authors: Czarnecki PG, Steinman TI

Abstract
Autosomal dominant polycystic kidney disease (ADPKD) represents the most prevalent inherited kidney disease, and an important contributor to renal and systemic morbidity. Almost 20 years after the discovery of the Pkd-1 and Pkd-2 genes, the exact molecular mechanisms of polycystic kidney disease pathogenesis still remain elusive. In the absence of a specific therapy for polycystic kidney disease, patients are treated for chronic kidney disease symptoms, like hypertension, anemia, hyperparathyroidism and pain. Intensive research on ADPKD and a variety of related complex cystic kidney disease syndromes revealed a network of intracellular signaling pathways that depend on ciliary function and include calcium- and cAMP-dependent mechanisms. Furthermore, proliferative and tissue patterning responses to mTOR, STAT, CDK and wnt signaling play an important role in various aspects of cystogenesis and represent further targets for therapy. Only a limited amount of clinical evidence from randomized controlled trials is currently available to evaluate treatment options. This includes ongoing trials of the vasopressin receptor-2 antagonist tolvaptan, as well as a set of studies that fail to show a clear therapeutic benefit of everolimus or sirolimus in PKD progression. Future research will involve the evaluation of small molecule inhibitors of growth factor receptor-, CDK- and STAT-pathways, as well as the characterization of novel biomarkers of disease progression and therapeutic response.

PMID: 23538311 [PubMed - in process]

ecdysone chir-258 dovitinib

Effects of Prostaglandins and COX Inhibiting Drugs on Skeletal Muscle Adaptations to Exercise.

Effects of Prostaglandins and COX Inhibiting Drugs on Skeletal Muscle Adaptations to Exercise.

J Appl Physiol. 2013 Mar 28;

Authors: Trappe TA, Liu SZ

Abstract
It has been ~40 years since the discovery that prostaglandins are produced by exercising skeletal muscle, and since the discovery that inhibition of prostaglandin synthesis is the mechanism of action of what are now known as cyclooxygenase (COX)-inhibiting drugs. Since that time, it has been established that prostaglandins are made during and after aerobic and resistance exercise and have a potent paracrine/autocrine effect on muscle metabolism. Consequently, it has also been determined that orally consumed doses of COX-inhibitors can profoundly influence muscle prostaglandin synthesis, muscle protein metabolism, and numerous other cellular processes that regulate muscle adaptations to exercise loading. Although data from acute human exercise studies, as well as animal and cell culture data would predict regular consumption of a COX-inhibitor during exercise training would dampen the typical muscle adaptations, the chronic data do not support this conjecture. From the studies in young and older individuals lasting from 1.5-4 months, no interfering effects of COX-inhibitors on muscle adaptations to resistance exercise training have been noted. In fact, in older individuals a substantial enhancement of muscle mass and strength has been observed. The collective findings of the prostaglandin/COX pathway regulation of skeletal muscle responses and adaptations to exercise are compelling. Considering the discoveries in other areas of COX regulation of health and disease there is certainly an interesting future of investigation in this re-emerging area, especially as it pertains to older individuals and the condition of sarcopenia, as well as exercise training and performance of individuals of all ages.

PMID: 23539318 [PubMed - as supplied by publisher]

chir-258 dovitinib dna-pk