A translocator protein ligand PK11195 shows antigrowth activity in human choriocarcinoma cells.

Related Articles

A translocator protein ligand PK11195 shows antigrowth activity in human choriocarcinoma cells.

Tumour Biol. 2012 Oct;33(5):1505-10

Authors: Takai N, Kira N, Ishii T, Yoshida T, Nishida M, Nishida Y, Nasu K, Takano M, Midori H, Koga S, Narahara H

Abstract
The potential anticancer agent 1-(2-chlorophenyl-N-methylpropyl)-3-isoquinolinecarboxamide (PK11195), a translocator protein ligand (initially described as a ligand for the peripheral benzodiazepine receptor), induces apoptosis in some lines of human tumor cells. We investigated the effect of PK11195 in the choriocarcinoma cell line, BeWo. BeWo cells were treated with various concentrations of PK11195, and changes in cell growth, the cell cycle, apoptosis, and related parameters were examined. A WST-1 assay showed that BeWo cells were sensitive to the growth inhibitory effect of PK11195. In contrast, the nonsite selective ligand diazepam has a little effect on these cells. Cell cycle analysis indicated that exposure to PK11195 decreased the proportion of cells in the S phase and increased the proportion in the G0/G1 phases of the cell cycle. Induction of apoptosis was confirmed by Annexin V staining of externalized phosphatidylserine, by the loss of mitochondrial transmembrane potential, and by antibodies directed against histones from fragmented DNA. This induction occurred in conjunction with the altered expression of genes related to cell growth, malignant phenotype, and apoptosis. These results suggest that PK11195 may serve as a therapeutic agent for the treatment of choriocarcinoma.

PMID: 22528948 [PubMed - indexed for MEDLINE]

ecdysone chir-258 dovitinib

Dovitinib preferentially targets endothelial cells rather than cancer cells for the inhibition of hepatocellular carcinoma growth and metastasis.

Dovitinib preferentially targets endothelial cells rather than cancer cells for the inhibition of hepatocellular carcinoma growth and metastasis.

J Transl Med. 2012 Dec 10;10(1):245

Authors: Chen ZY, Shi M, Peng LX, Wei W, Li XJ, Guo ZX, Li SH, Zhong C, Qian CN, Guo RP

Abstract
ABSTRACT: BACKGROUND: Dovitinib is a receptor tyrosine kinase (RTK) inhibitor targeting vascular endothelial growth factor receptors, fibroblast growth factor receptors and platelet-derived growth factor receptor beta. Dovitinib is currently in clinical trials for the treatment of hepatocellular carcinoma (HCC). METHOD: In this study, we used five HCC cell lines and five endothelial cell lines to validate molecular and cellular targets of dovitinib. RESULTS: Tumor growth and pulmonary metastasis were significantly suppressed in an orthotopic HCC model. Immunoblotting revealed that among known dovitinib targets, only PDGFR-beta was expressed in two HCC cell lines, while four of five endothelial lines expressed PDGFR-beta, FGFR-1, and VEGFR-2. Dovitinib inhibited endothelial cell proliferation and motility at 0.04 mumol/L, a pharmacologically relevant concentration; it was unable to inhibit the proliferation or motility of HCC cells at the same concentration. Immunohistochemical analyses showed that dovitinib significantly decreased the microvessel density of xenograft tumors, inhibiting proliferation and inducing apoptosis in HCC cells. CONCLUSION: Our findings indicate that dovitinib inhibits HCC growth and metastasis preferentially through an antiangiogenic mechanism, not through direct targeting of HCC cells.

PMID: 23228017 [PubMed - as supplied by publisher]

ecdysone chir-258 dovitinib

The Mammalian target of rapamycin inhibitors in breast cancer: current evidence and future directions.

The Mammalian target of rapamycin inhibitors in breast cancer: current evidence and future directions.

Anticancer Res. 2013 Jan;33(1):21-8

Authors: Malaguti P, Vari S, Cognetti F, Fabi A

Abstract
Mammalian target of rapamycin (mTOR) is a crucial mediator of tumor progression and may be a promising target in a significant proportion of patients with breast cancer. More specifically, the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT)/mTOR pathway plays a critical role in multiple cellular functions including metabolism, proliferation, growth and survival. This pathway is higly active in many types of cancer and is linked to resistance to many types of therapy. Direct blockade of the mTOR pathway is a new area in breast cancer therapy, with the potential to modulate growth factor- and estrogen-dependent and estrogen-independent pathways, which contribute to the pathogenesis and progression of tumors. Thus, inhibitors of mTOR are of interest as potential therapeutic agents for patients with breast cancer, everolimus and temsirolimus being the main representatives of this category. This review of the literature analyzes the available data emerging from trials and evaluates the efficacy and safety of mTOR inhibitors in all subtypes of breast cancer.

PMID: 23267124 [PubMed - in process]

rad001 ecdysone chir-258

Dovitinib preferentially targets endothelial cells rather than cancer cells for the inhibition of hepatocellular carcinoma growth and metastasis.

Dovitinib preferentially targets endothelial cells rather than cancer cells for the inhibition of hepatocellular carcinoma growth and metastasis.

J Transl Med. 2012 Dec 10;10(1):245

Authors: Chen ZY, Shi M, Peng LX, Wei W, Li XJ, Guo ZX, Li SH, Zhong C, Qian CN, Guo RP

Abstract
ABSTRACT: BACKGROUND: Dovitinib is a receptor tyrosine kinase (RTK) inhibitor targeting vascular endothelial growth factor receptors, fibroblast growth factor receptors and platelet-derived growth factor receptor beta. Dovitinib is currently in clinical trials for the treatment of hepatocellular carcinoma (HCC). METHOD: In this study, we used five HCC cell lines and five endothelial cell lines to validate molecular and cellular targets of dovitinib. RESULTS: Tumor growth and pulmonary metastasis were significantly suppressed in an orthotopic HCC model. Immunoblotting revealed that among known dovitinib targets, only PDGFR-beta was expressed in two HCC cell lines, while four of five endothelial lines expressed PDGFR-beta, FGFR-1, and VEGFR-2. Dovitinib inhibited endothelial cell proliferation and motility at 0.04 mumol/L, a pharmacologically relevant concentration; it was unable to inhibit the proliferation or motility of HCC cells at the same concentration. Immunohistochemical analyses showed that dovitinib significantly decreased the microvessel density of xenograft tumors, inhibiting proliferation and inducing apoptosis in HCC cells. CONCLUSION: Our findings indicate that dovitinib inhibits HCC growth and metastasis preferentially through an antiangiogenic mechanism, not through direct targeting of HCC cells.

PMID: 23228017 [PubMed - as supplied by publisher]

chir-258 dovitinib dna-pk

A validated tumorgraft model reveals activity of dovitinib against renal cell carcinoma.

Related Articles

A validated tumorgraft model reveals activity of dovitinib against renal cell carcinoma.

Sci Transl Med. 2012 Jun 6;4(137):137ra75

Authors: Sivanand S, Pe�a-Llopis S, Zhao H, Kucejova B, Spence P, Pavia-Jimenez A, Yamasaki T, McBride DJ, Gillen J, Wolff NC, Morlock L, Lotan Y, Raj GV, Sagalowsky A, Margulis V, Cadeddu JA, Ross MT, Bentley DR, Kabbani W, Xie XJ, Kapur P, Williams NS, Brugarolas J

Abstract
Most anticancer drugs entering clinical trials fail to achieve approval from the U.S. Food and Drug Administration. Drug development is hampered by the lack of preclinical models with therapeutic predictive value. Herein, we report the development and validation of a tumorgraft model of renal cell carcinoma (RCC) and its application to the evaluation of an experimental drug. Tumor samples from 94 patients were implanted in the kidneys of mice without additives or disaggregation. Tumors from 35 of these patients formed tumorgrafts, and 16 stable lines were established. Samples from metastatic sites engrafted at higher frequency than those from primary tumors, and stable engraftment of primary tumors in mice correlated with decreased patient survival. Tumorgrafts retained the histology, gene expression, DNA copy number alterations, and more than 90% of the protein-coding gene mutations of the corresponding tumors. As determined by the induction of hypercalcemia in tumorgraft-bearing mice, tumorgrafts retained the ability to induce paraneoplastic syndromes. In studies simulating drug exposures in patients, RCC tumorgraft growth was inhibited by sunitinib and sirolimus (the active metabolite of temsirolimus in humans), but not by erlotinib, which was used as a control. Dovitinib, a drug in clinical development, showed greater activity than sunitinib and sirolimus. The routine incorporation of models recapitulating the molecular genetics and drug sensitivities of human tumors into preclinical programs has the potential to improve oncology drug development.

PMID: 22674553 [PubMed - indexed for MEDLINE]

zm-447439 rad001 ecdysone

Improvement of pest resistance in transgenic tobacco plants expressing dsRNA of an insect-associated gene EcR.

Related Articles

Improvement of pest resistance in transgenic tobacco plants expressing dsRNA of an insect-associated gene EcR.

PLoS One. 2012;7(6):e38572

Authors: Zhu JQ, Liu S, Ma Y, Zhang JQ, Qi HS, Wei ZJ, Yao Q, Zhang WQ, Li S

Abstract
The adoption of pest-resistant transgenic plants to reduce yield loss and pesticide utilization has been successful in the past three decades. Recently, transgenic plant expressing double-stranded RNA (dsRNA) targeting pest genes emerges as a promising strategy for improving pest resistance in crops. The steroid hormone, 20-hydroxyecdysone (20E), predominately controls insect molting via its nuclear receptor complex, EcR-USP. Here we report that pest resistance is improved in transgenic tobacco plants expressing dsRNA of EcR from the cotton bollworm, Helicoverpa armigera, a serious lepidopteran pest for a variety of crops. When H. armigera larvae were fed with the whole transgenic tobacco plants expressing EcR dsRNA, resistance to H. armigera was significantly improved in transgenic plants. Meanwhile, when H. armigera larvae were fed with leaves of transgenic tobacco plants expressing EcR dsRNA, its EcR mRNA level was dramatically decreased causing molting defects and larval lethality. In addition, the transgenic tobacco plants expressing H. armigera EcR dsRNA were also resistant to another lepidopteran pest, the beet armyworm, Spodoptera exigua, due to the high similarity in the nucleotide sequences of their EcR genes. This study provides additional evidence that transgenic plant expressing dsRNA targeting insect-associated genes is able to improve pest resistance.

PMID: 22685585 [PubMed - indexed for MEDLINE]

ecdysone chir-258 dovitinib

Improvement of pest resistance in transgenic tobacco plants expressing dsRNA of an insect-associated gene EcR.

Related Articles

Improvement of pest resistance in transgenic tobacco plants expressing dsRNA of an insect-associated gene EcR.

PLoS One. 2012;7(6):e38572

Authors: Zhu JQ, Liu S, Ma Y, Zhang JQ, Qi HS, Wei ZJ, Yao Q, Zhang WQ, Li S

Abstract
The adoption of pest-resistant transgenic plants to reduce yield loss and pesticide utilization has been successful in the past three decades. Recently, transgenic plant expressing double-stranded RNA (dsRNA) targeting pest genes emerges as a promising strategy for improving pest resistance in crops. The steroid hormone, 20-hydroxyecdysone (20E), predominately controls insect molting via its nuclear receptor complex, EcR-USP. Here we report that pest resistance is improved in transgenic tobacco plants expressing dsRNA of EcR from the cotton bollworm, Helicoverpa armigera, a serious lepidopteran pest for a variety of crops. When H. armigera larvae were fed with the whole transgenic tobacco plants expressing EcR dsRNA, resistance to H. armigera was significantly improved in transgenic plants. Meanwhile, when H. armigera larvae were fed with leaves of transgenic tobacco plants expressing EcR dsRNA, its EcR mRNA level was dramatically decreased causing molting defects and larval lethality. In addition, the transgenic tobacco plants expressing H. armigera EcR dsRNA were also resistant to another lepidopteran pest, the beet armyworm, Spodoptera exigua, due to the high similarity in the nucleotide sequences of their EcR genes. This study provides additional evidence that transgenic plant expressing dsRNA targeting insect-associated genes is able to improve pest resistance.

PMID: 22685585 [PubMed - indexed for MEDLINE]

rad001 ecdysone chir-258

Tetraploidization increases sensitivity to Aurora B kinase inhibition.

Related Articles

Tetraploidization increases sensitivity to Aurora B kinase inhibition.

Cell Cycle. 2012 Jul 1;11(13):2567-77

Authors: Marxer M, Foucar CE, Man WY, Chen Y, Ma HT, Poon RY

Abstract
Aurora kinases are overexpressed in many cancers and are targets for anticancer drugs. The yeast homolog of Aurora B kinase, IPL1, was found to be a ploidy-specific lethality gene. Given that polyploidization is a common feature of many cancers, we hypothesized polyploidization also sensitizes mammalian cells to inhibition of Aurora kinases. Using two models of apparent diploid vs. tetraploid cell lines (one based on the hepatocellular carcinoma cell line Hep3B and another on untransformed mouse fibroblasts), we found that tetraploid cells were more sensitive to Aurora B inhibition than their diploid counterparts. Apoptosis could be induced in tetraploid cells by two different Aurora B inhibitors. Furthermore, tetraploid cells were sensitive to Aurora B inhibition but were not affected by Aurora A inhibition. Interestingly, the underlying mechanism was due to mitotic slippage and the subsequent excessive genome reduplication. In support of this, abolition of cytokinesis with dihydrocytochalasin B resulted in similar effects on tetraploid cells as Aurora B inhibition. These results indicate that inhibition of Aurora B or cytokinesis can promote apoptosis effectively in polyploid cancer cells.

PMID: 22722494 [PubMed - in process]

coxinhibitors c-met inhibitors zm-447439

Improvement of pest resistance in transgenic tobacco plants expressing dsRNA of an insect-associated gene EcR.

Related Articles

Improvement of pest resistance in transgenic tobacco plants expressing dsRNA of an insect-associated gene EcR.

PLoS One. 2012;7(6):e38572

Authors: Zhu JQ, Liu S, Ma Y, Zhang JQ, Qi HS, Wei ZJ, Yao Q, Zhang WQ, Li S

Abstract
The adoption of pest-resistant transgenic plants to reduce yield loss and pesticide utilization has been successful in the past three decades. Recently, transgenic plant expressing double-stranded RNA (dsRNA) targeting pest genes emerges as a promising strategy for improving pest resistance in crops. The steroid hormone, 20-hydroxyecdysone (20E), predominately controls insect molting via its nuclear receptor complex, EcR-USP. Here we report that pest resistance is improved in transgenic tobacco plants expressing dsRNA of EcR from the cotton bollworm, Helicoverpa armigera, a serious lepidopteran pest for a variety of crops. When H. armigera larvae were fed with the whole transgenic tobacco plants expressing EcR dsRNA, resistance to H. armigera was significantly improved in transgenic plants. Meanwhile, when H. armigera larvae were fed with leaves of transgenic tobacco plants expressing EcR dsRNA, its EcR mRNA level was dramatically decreased causing molting defects and larval lethality. In addition, the transgenic tobacco plants expressing H. armigera EcR dsRNA were also resistant to another lepidopteran pest, the beet armyworm, Spodoptera exigua, due to the high similarity in the nucleotide sequences of their EcR genes. This study provides additional evidence that transgenic plant expressing dsRNA targeting insect-associated genes is able to improve pest resistance.

PMID: 22685585 [PubMed - indexed for MEDLINE]

ecdysone chir-258 dovitinib

A translocator protein ligand PK11195 shows antigrowth activity in human choriocarcinoma cells.

Related Articles

A translocator protein ligand PK11195 shows antigrowth activity in human choriocarcinoma cells.

Tumour Biol. 2012 Oct;33(5):1505-10

Authors: Takai N, Kira N, Ishii T, Yoshida T, Nishida M, Nishida Y, Nasu K, Takano M, Midori H, Koga S, Narahara H

Abstract
The potential anticancer agent 1-(2-chlorophenyl-N-methylpropyl)-3-isoquinolinecarboxamide (PK11195), a translocator protein ligand (initially described as a ligand for the peripheral benzodiazepine receptor), induces apoptosis in some lines of human tumor cells. We investigated the effect of PK11195 in the choriocarcinoma cell line, BeWo. BeWo cells were treated with various concentrations of PK11195, and changes in cell growth, the cell cycle, apoptosis, and related parameters were examined. A WST-1 assay showed that BeWo cells were sensitive to the growth inhibitory effect of PK11195. In contrast, the nonsite selective ligand diazepam has a little effect on these cells. Cell cycle analysis indicated that exposure to PK11195 decreased the proportion of cells in the S phase and increased the proportion in the G0/G1 phases of the cell cycle. Induction of apoptosis was confirmed by Annexin V staining of externalized phosphatidylserine, by the loss of mitochondrial transmembrane potential, and by antibodies directed against histones from fragmented DNA. This induction occurred in conjunction with the altered expression of genes related to cell growth, malignant phenotype, and apoptosis. These results suggest that PK11195 may serve as a therapeutic agent for the treatment of choriocarcinoma.

PMID: 22528948 [PubMed - indexed for MEDLINE]

chir-258 dovitinib dna-pk

A new synthetic chalcone derivative, 2-hydroxy-3',5,5'-trimethoxychalcone (DK-139), suppresses the Toll-like receptor 4-mediated inflammatory response through inhibition of the Akt/NF-?B pathway in BV2 microglial cells.

Related Articles

A new synthetic chalcone derivative, 2-hydroxy-3',5,5'-trimethoxychalcone (DK-139), suppresses the Toll-like receptor 4-mediated inflammatory response through inhibition of the Akt/NF-?B pathway in BV2 microglial cells.

Exp Mol Med. 2012 Jun 30;44(6):369-77

Authors: Lee YH, Jeon SH, Kim SH, Kim C, Lee SJ, Koh D, Lim Y, Ha K, Shin SY

Abstract
Microglial cells are the resident innate immune cells that sense pathogens and tissue injury in the central nervous system (CNS). Microglial activation is critical for neuroinflammatory responses. The synthetic compound 2-hydroxy-3',5,5'-trimethoxychalcone (DK-139) is a novel chalcone-derived compound. In this study, we investigated the effects of DK-139 on Toll-like receptor 4 (TLR4)-mediated inflammatory responses in BV2 microglial cells. DK-139 inhibited lipopolysaccharide (LPS)-induced TLR4 activity, as determined using a cell-based assay. DK-139 blocked LPS-induced phosphorylation of I?B and p65/RelA NF-?B, resulting in inhibition of the nuclear translocation and trans-acting activity of NF-?B in BV2 microglial cells. We also found that DK-139 reduced the expression of NF-?B target genes, such as those for COX-2, iNOS, and IL-1?, in LPS-stimulated BV2 microglial cells. Interestingly, DK-139 blocked LPS-induced Akt phosphorylation. Inhibition of Akt abrogated LPS-induced phosphorylation of p65/RelA, while overexpression of dominant- active p110CAAX enhanced p65/RelA phosphorylation as well as iNOS and COX2 expression. These results suggest that DK-139 exerts an anti-inflammatory effect on microglial cells by inhibiting the Akt/I?B kinase (IKK)/NF-?B signaling pathway.

PMID: 22382990 [PubMed - indexed for MEDLINE]

dovitinib dna-pk coxinhibitors

Impact of 5-lipoxygenase inhibitors on the spatiotemporal distribution of inflammatory cells and neuronal COX-2 expression following experimental traumatic brain injury in rats.

Impact of 5-lipoxygenase inhibitors on the spatiotemporal distribution of inflammatory cells and neuronal COX-2 expression following experimental traumatic brain injury in rats.

Brain Res. 2012 Dec 22;

Authors: H�rtig W, Michalski D, Seeger G, Voigt C, Donat CK, Dulin J, Kacza J, Meixensberger J, Arendt T, Schuhmann MU

Abstract
The inflammatory response following traumatic brain injury (TBI) contributes to neuronal death with poor outcome. Although anti-inflammatory strategies were beneficial in experimental TBI, clinical translations mostly failed, probably caused by the complexity of involved cells and mediators. We recently showed in a rat model of controlled cortical impact (CCI) that leukotriene inhibitors (LIs) attenuate contusion growth and improve neuronal survival. This study focuses on spatiotemporal characteristics of macrophages and granulocytes, typically involved in inflammatory processes, and neuronal COX-2 expression. Effects of treatment with LIs (Boscari/MK-886), started prior trauma, were evaluated by quantifying CD68(+), CD43(+) and COX-2(+) cells 24h and 72h post-CCI in the parietal cortex (PC), CA3 region, dentate gyrus (DG) and visual/auditory cortex (v/aC). Correlations were applied to identify inter-cellular relationships. At 24h, untreated animals showed granulocyte invasion in all regions, decreasing towards 72h. Macrophages increased from 24h to 72h post-CCI in PC and v/aC. COX-2(+) neurones showed no temporal changes, except of an increase in the CA3 region at 72h. Treatment reduced granulocytes at 24h in the pericontusional zone and hippocampus, and macrophages at 72h in the PC and v/aC. COX-2 expression remained unaffected by LIs, except of time-specific changes in the DG (increase/decrease at 24/72h). Interrelations confirmed concomitant cellular reactions beyond the initial trauma site. In conclusion, LIs attenuated the cellular inflammatory response following CCI. Future studies have to clarify region-specific effects and explore the potential of a clinically more relevant therapeutic approach applying LIs after CCI.

PMID: 23268351 [PubMed - as supplied by publisher]

c-met inhibitors zm-447439 rad001

Tetraploidization increases sensitivity to Aurora B kinase inhibition.

Related Articles

Tetraploidization increases sensitivity to Aurora B kinase inhibition.

Cell Cycle. 2012 Jul 1;11(13):2567-77

Authors: Marxer M, Foucar CE, Man WY, Chen Y, Ma HT, Poon RY

Abstract
Aurora kinases are overexpressed in many cancers and are targets for anticancer drugs. The yeast homolog of Aurora B kinase, IPL1, was found to be a ploidy-specific lethality gene. Given that polyploidization is a common feature of many cancers, we hypothesized polyploidization also sensitizes mammalian cells to inhibition of Aurora kinases. Using two models of apparent diploid vs. tetraploid cell lines (one based on the hepatocellular carcinoma cell line Hep3B and another on untransformed mouse fibroblasts), we found that tetraploid cells were more sensitive to Aurora B inhibition than their diploid counterparts. Apoptosis could be induced in tetraploid cells by two different Aurora B inhibitors. Furthermore, tetraploid cells were sensitive to Aurora B inhibition but were not affected by Aurora A inhibition. Interestingly, the underlying mechanism was due to mitotic slippage and the subsequent excessive genome reduplication. In support of this, abolition of cytokinesis with dihydrocytochalasin B resulted in similar effects on tetraploid cells as Aurora B inhibition. These results indicate that inhibition of Aurora B or cytokinesis can promote apoptosis effectively in polyploid cancer cells.

PMID: 22722494 [PubMed - in process]

ecdysone chir-258 dovitinib

DREF is involved in the steroidogenesis via regulation of shadow gene.

DREF is involved in the steroidogenesis via regulation of shadow gene.

Am J Cancer Res. 2012;2(6):714-25

Authors: Park JS, Choi YJ, Thao DT, Kim YS, Yamaguchi M, Yoo MA

Abstract
The Drosophila DNA replication-related element-binding factor (dDREF) has been identified as a master regulator of cell proliferation-related genes via its binding to the DRE sequence, 5'-TATCGATA. However, the biological roles of DREF are still to be clarified. Here, we show that DREF mutant females have steroid hormone ecdysone-deficient phenotypes, such as the loss of vitellogenic egg chambers. Furthermore, DREF knockdown in the prothoracic gland of larva prevented pupation and this was rescued via 20-hydroxyecdysone treatment. We found a DRE-like sequence (-625 to -632) in the 5'-flanking region of the Drosophila shadow gene, which catalyzes the conversion of 2-deoxyecdysone to ecdysone, and demonstrated that shadow is a novel target gene of dDREF using quantitative RT-PCR and Chip assays. In addition, we show that the level of dDREF protein correlated with age-related changes in the level of shadow mRNA in the ovaries of wild-type flies. Taken together, our data indicate that dDREF plays a key role in steroid synthesis via regulation of the shadow gene.

PMID: 23226617 [PubMed]

zm-447439 rad001 ecdysone

Novel benzoxazole inhibitors of mPGES-1.

Novel benzoxazole inhibitors of mPGES-1.

Bioorg Med Chem Lett. 2012 Oct 16;

Authors: Kablaoui N, Patel S, Shao J, Demian D, Hoffmaster K, Berlioz F, Vazquez ML, Moore WM, Nugent RA

Abstract
A novel series of potent benzoxazole mPGES-1 inhibitors has been derived from a hit from a high throughput screen. Compound 37 displays mPGES-1 inhibition in an enzyme assay (0.018?M) and PGE-2 inhibition in a cell-based assay (0.034?M). It demonstrates 500- and 2500-fold selectivity for mPGES-1 over COX-2 and 6-keto PGF-1?, respectively. In vivo PK studies in dogs demonstrate 55% oral bioavailability and an 7h half-life.

PMID: 23266122 [PubMed - as supplied by publisher]

chir-258 dovitinib dna-pk

New insights into the roles of ATM and DNA-PKcs in the cellular response to oxidative stress.

Related Articles

New insights into the roles of ATM and DNA-PKcs in the cellular response to oxidative stress.

Cancer Lett. 2012 Dec 31;327(1-2):103-10

Authors: Chen BP, Li M, Asaithamby A

Abstract
Reactive oxygen species (ROS) are induced by a variety of endogenous and exogenous sources. At pathologically high levels, ROS cause damage to biological molecules, including DNA. The damage sustained by DNA likely plays a key role in the pathogenesis of aging and carcinogenesis. Extensive research has established in detail the mechanism of cellular response to oxidative stress. Attention is now focused on identifying the molecular contributions of the key DNA damage response kinases ataxia telangiectasia mutated (ATM), DNA-dependent protein kinase catalytic subunit (DNA-PKcs), and ATM- and Rad3-related (ATR) in the oxidative stress response. In this review, we will provide an update of the current evidence regarding the involvement of these related DNA damage response kinases in oxidative DNA lesion repair and signaling responses. The growing understanding of the involvement of ATM, DNA-PKcs, and ATR in the oxidative stress response will offer new possibilities for the treatment of ROS-related diseases.

PMID: 22155347 [PubMed - indexed for MEDLINE]

dovitinib dna-pk coxinhibitors

DREF is involved in the steroidogenesis via regulation of shadow gene.

DREF is involved in the steroidogenesis via regulation of shadow gene.

Am J Cancer Res. 2012;2(6):714-25

Authors: Park JS, Choi YJ, Thao DT, Kim YS, Yamaguchi M, Yoo MA

Abstract
The Drosophila DNA replication-related element-binding factor (dDREF) has been identified as a master regulator of cell proliferation-related genes via its binding to the DRE sequence, 5'-TATCGATA. However, the biological roles of DREF are still to be clarified. Here, we show that DREF mutant females have steroid hormone ecdysone-deficient phenotypes, such as the loss of vitellogenic egg chambers. Furthermore, DREF knockdown in the prothoracic gland of larva prevented pupation and this was rescued via 20-hydroxyecdysone treatment. We found a DRE-like sequence (-625 to -632) in the 5'-flanking region of the Drosophila shadow gene, which catalyzes the conversion of 2-deoxyecdysone to ecdysone, and demonstrated that shadow is a novel target gene of dDREF using quantitative RT-PCR and Chip assays. In addition, we show that the level of dDREF protein correlated with age-related changes in the level of shadow mRNA in the ovaries of wild-type flies. Taken together, our data indicate that dDREF plays a key role in steroid synthesis via regulation of the shadow gene.

PMID: 23226617 [PubMed]

ecdysone chir-258 dovitinib

Novel benzoxazole inhibitors of mPGES-1.

Novel benzoxazole inhibitors of mPGES-1.

Bioorg Med Chem Lett. 2012 Oct 16;

Authors: Kablaoui N, Patel S, Shao J, Demian D, Hoffmaster K, Berlioz F, Vazquez ML, Moore WM, Nugent RA

Abstract
A novel series of potent benzoxazole mPGES-1 inhibitors has been derived from a hit from a high throughput screen. Compound 37 displays mPGES-1 inhibition in an enzyme assay (0.018?M) and PGE-2 inhibition in a cell-based assay (0.034?M). It demonstrates 500- and 2500-fold selectivity for mPGES-1 over COX-2 and 6-keto PGF-1?, respectively. In vivo PK studies in dogs demonstrate 55% oral bioavailability and an 7h half-life.

PMID: 23266122 [PubMed - as supplied by publisher]

rad001 ecdysone chir-258

Dovitinib preferentially targets endothelial cells rather than cancer cells for the inhibition of hepatocellular carcinoma growth and metastasis.

Dovitinib preferentially targets endothelial cells rather than cancer cells for the inhibition of hepatocellular carcinoma growth and metastasis.

J Transl Med. 2012 Dec 10;10(1):245

Authors: Chen ZY, Shi M, Peng LX, Wei W, Li XJ, Guo ZX, Li SH, Zhong C, Qian CN, Guo RP

Abstract
ABSTRACT: BACKGROUND: Dovitinib is a receptor tyrosine kinase (RTK) inhibitor targeting vascular endothelial growth factor receptors, fibroblast growth factor receptors and platelet-derived growth factor receptor beta. Dovitinib is currently in clinical trials for the treatment of hepatocellular carcinoma (HCC). METHOD: In this study, we used five HCC cell lines and five endothelial cell lines to validate molecular and cellular targets of dovitinib. RESULTS: Tumor growth and pulmonary metastasis were significantly suppressed in an orthotopic HCC model. Immunoblotting revealed that among known dovitinib targets, only PDGFR-beta was expressed in two HCC cell lines, while four of five endothelial lines expressed PDGFR-beta, FGFR-1, and VEGFR-2. Dovitinib inhibited endothelial cell proliferation and motility at 0.04 mumol/L, a pharmacologically relevant concentration; it was unable to inhibit the proliferation or motility of HCC cells at the same concentration. Immunohistochemical analyses showed that dovitinib significantly decreased the microvessel density of xenograft tumors, inhibiting proliferation and inducing apoptosis in HCC cells. CONCLUSION: Our findings indicate that dovitinib inhibits HCC growth and metastasis preferentially through an antiangiogenic mechanism, not through direct targeting of HCC cells.

PMID: 23228017 [PubMed - as supplied by publisher]

coxinhibitors c-met inhibitors zm-447439

Improvement of pest resistance in transgenic tobacco plants expressing dsRNA of an insect-associated gene EcR.

Related Articles

Improvement of pest resistance in transgenic tobacco plants expressing dsRNA of an insect-associated gene EcR.

PLoS One. 2012;7(6):e38572

Authors: Zhu JQ, Liu S, Ma Y, Zhang JQ, Qi HS, Wei ZJ, Yao Q, Zhang WQ, Li S

Abstract
The adoption of pest-resistant transgenic plants to reduce yield loss and pesticide utilization has been successful in the past three decades. Recently, transgenic plant expressing double-stranded RNA (dsRNA) targeting pest genes emerges as a promising strategy for improving pest resistance in crops. The steroid hormone, 20-hydroxyecdysone (20E), predominately controls insect molting via its nuclear receptor complex, EcR-USP. Here we report that pest resistance is improved in transgenic tobacco plants expressing dsRNA of EcR from the cotton bollworm, Helicoverpa armigera, a serious lepidopteran pest for a variety of crops. When H. armigera larvae were fed with the whole transgenic tobacco plants expressing EcR dsRNA, resistance to H. armigera was significantly improved in transgenic plants. Meanwhile, when H. armigera larvae were fed with leaves of transgenic tobacco plants expressing EcR dsRNA, its EcR mRNA level was dramatically decreased causing molting defects and larval lethality. In addition, the transgenic tobacco plants expressing H. armigera EcR dsRNA were also resistant to another lepidopteran pest, the beet armyworm, Spodoptera exigua, due to the high similarity in the nucleotide sequences of their EcR genes. This study provides additional evidence that transgenic plant expressing dsRNA targeting insect-associated genes is able to improve pest resistance.

PMID: 22685585 [PubMed - indexed for MEDLINE]

chir-258 dovitinib dna-pk

Tetraploidization increases sensitivity to Aurora B kinase inhibition.

Related Articles

Tetraploidization increases sensitivity to Aurora B kinase inhibition.

Cell Cycle. 2012 Jul 1;11(13):2567-77

Authors: Marxer M, Foucar CE, Man WY, Chen Y, Ma HT, Poon RY

Abstract
Aurora kinases are overexpressed in many cancers and are targets for anticancer drugs. The yeast homolog of Aurora B kinase, IPL1, was found to be a ploidy-specific lethality gene. Given that polyploidization is a common feature of many cancers, we hypothesized polyploidization also sensitizes mammalian cells to inhibition of Aurora kinases. Using two models of apparent diploid vs. tetraploid cell lines (one based on the hepatocellular carcinoma cell line Hep3B and another on untransformed mouse fibroblasts), we found that tetraploid cells were more sensitive to Aurora B inhibition than their diploid counterparts. Apoptosis could be induced in tetraploid cells by two different Aurora B inhibitors. Furthermore, tetraploid cells were sensitive to Aurora B inhibition but were not affected by Aurora A inhibition. Interestingly, the underlying mechanism was due to mitotic slippage and the subsequent excessive genome reduplication. In support of this, abolition of cytokinesis with dihydrocytochalasin B resulted in similar effects on tetraploid cells as Aurora B inhibition. These results indicate that inhibition of Aurora B or cytokinesis can promote apoptosis effectively in polyploid cancer cells.

PMID: 22722494 [PubMed - in process]

c-met inhibitors zm-447439 rad001

Tetraploidization increases sensitivity to Aurora B kinase inhibition.

Related Articles

Tetraploidization increases sensitivity to Aurora B kinase inhibition.

Cell Cycle. 2012 Jul 1;11(13):2567-77

Authors: Marxer M, Foucar CE, Man WY, Chen Y, Ma HT, Poon RY

Abstract
Aurora kinases are overexpressed in many cancers and are targets for anticancer drugs. The yeast homolog of Aurora B kinase, IPL1, was found to be a ploidy-specific lethality gene. Given that polyploidization is a common feature of many cancers, we hypothesized polyploidization also sensitizes mammalian cells to inhibition of Aurora kinases. Using two models of apparent diploid vs. tetraploid cell lines (one based on the hepatocellular carcinoma cell line Hep3B and another on untransformed mouse fibroblasts), we found that tetraploid cells were more sensitive to Aurora B inhibition than their diploid counterparts. Apoptosis could be induced in tetraploid cells by two different Aurora B inhibitors. Furthermore, tetraploid cells were sensitive to Aurora B inhibition but were not affected by Aurora A inhibition. Interestingly, the underlying mechanism was due to mitotic slippage and the subsequent excessive genome reduplication. In support of this, abolition of cytokinesis with dihydrocytochalasin B resulted in similar effects on tetraploid cells as Aurora B inhibition. These results indicate that inhibition of Aurora B or cytokinesis can promote apoptosis effectively in polyploid cancer cells.

PMID: 22722494 [PubMed - in process]

dna-pk coxinhibitors c-met inhibitors

Dovitinib preferentially targets endothelial cells rather than cancer cells for the inhibition of hepatocellular carcinoma growth and metastasis.

Dovitinib preferentially targets endothelial cells rather than cancer cells for the inhibition of hepatocellular carcinoma growth and metastasis.

J Transl Med. 2012 Dec 10;10(1):245

Authors: Chen ZY, Shi M, Peng LX, Wei W, Li XJ, Guo ZX, Li SH, Zhong C, Qian CN, Guo RP

Abstract
ABSTRACT: BACKGROUND: Dovitinib is a receptor tyrosine kinase (RTK) inhibitor targeting vascular endothelial growth factor receptors, fibroblast growth factor receptors and platelet-derived growth factor receptor beta. Dovitinib is currently in clinical trials for the treatment of hepatocellular carcinoma (HCC). METHOD: In this study, we used five HCC cell lines and five endothelial cell lines to validate molecular and cellular targets of dovitinib. RESULTS: Tumor growth and pulmonary metastasis were significantly suppressed in an orthotopic HCC model. Immunoblotting revealed that among known dovitinib targets, only PDGFR-beta was expressed in two HCC cell lines, while four of five endothelial lines expressed PDGFR-beta, FGFR-1, and VEGFR-2. Dovitinib inhibited endothelial cell proliferation and motility at 0.04 mumol/L, a pharmacologically relevant concentration; it was unable to inhibit the proliferation or motility of HCC cells at the same concentration. Immunohistochemical analyses showed that dovitinib significantly decreased the microvessel density of xenograft tumors, inhibiting proliferation and inducing apoptosis in HCC cells. CONCLUSION: Our findings indicate that dovitinib inhibits HCC growth and metastasis preferentially through an antiangiogenic mechanism, not through direct targeting of HCC cells.

PMID: 23228017 [PubMed - as supplied by publisher]

chir-258 dovitinib dna-pk

Constitutively active c-Met kinase in PC-3 cells is autocrine-independent and can be blocked by the Met kinase inhibitor BMS-777607.

Related Articles

Constitutively active c-Met kinase in PC-3 cells is autocrine-independent and can be blocked by the Met kinase inhibitor BMS-777607.

BMC Cancer. 2012;12:198

Authors: Dai Y, Siemann DW

Abstract
BACKGROUND: The c-Met receptor tyrosine kinase is aberrantly activated in many solid tumors. In a prior study we showed that prostate cancer PC-3 cells exhibit constitutively activated c-Met without exogenous hepatocyte growth factor (HGF); however whether this characteristic is due to an endogenous HGF/c-Met autocrine loop remains controversial. In the current study we examined the response of PC-3 cells to an anti-HGF neutralizing antibody or a small molecule Met kinase inhibitor (BMS-777607).
METHODS: Cell scattering was tested by monitoring cell morphology after HGF stimulation. Cell migration was examined by both "wound-healing" and transwell assasy and invasion was detected by Matrigel-coated transwell assay. Proliferation, survival and anoikis were determined by MTT, colony formation and trypan blue exclusion assay, respectively. Gene and protein expression were assessed by real-time PCR and Western blot, respectively.
RESULTS: Although HGF mRNA could be detected in PC-3 cells, the molecular weight of secreted "HGF" protein was inconsistent with the functional recombinant HGF. Furthermore, conditioned medium from PC-3 cell cultures was ineffective at triggering either motogenic behavior or c-Met signaling in DU145, another prostate cancer cell line expressing c-Met but lacking basal c-Met activation. PC-3 cells also were not responsive to the anti-HGF neutralizing antibody in experiments assessing proliferation, migration, or c-Met signaling. BMS-777607 treatment with micromolar doses nonetheless led to significant inhibition of multiple PC-3 cell functions including proliferation, clonogenicity, migration and invasion. At the molecular level, BMS-777607 suppressed autophosphorylated c-Met and downstream c-Src and Akt pathways.
CONCLUSIONS: These results suggest that the constitutive c-Met activation in PC-3 is independent of autocrine stimulation. Because PC-3 cells were responsive to BMS-777607 but not the anti-HGF antibody, the findings also indicate that under circumstances where c-Met is constitutively hyperactive in the absence of functional HGF, targeting the c-Met receptor remains a viable therapeutic option to impede cancer progression.

PMID: 22639908 [PubMed - indexed for MEDLINE]

coxinhibitors c-met inhibitors zm-447439

Induction of P-glycoprotein and Bcrp at the rat blood-brain barrier following a subchronic morphine treatment is mediated through NMDA/COX-2 activation.

Related Articles

Induction of P-glycoprotein and Bcrp at the rat blood-brain barrier following a subchronic morphine treatment is mediated through NMDA/COX-2 activation.

J Neurochem. 2012 Nov;123(4):491-503

Authors: Yousif S, Chaves C, Potin S, Margaill I, Scherrmann JM, Decl�ves X

Abstract
Subchronic morphine treatment induces P-glycoprotein (P-gp) up-regulation at the blood-brain barrier. This study investigates the rate and extent to which P-gp and breast cancer-resistance protein (Bcrp) increase at the rat blood-brain barrier following subchronic morphine treatment. Rats were given increasing doses of morphine (10-40 mg/kg) or saline i.p. twice daily for 5 days. The brain cortex large vessels and microvessels were then mechanical isolated 6, 9, 12, 24, and 36 h after the last injection. The gene and protein expression of P-gp and Bcrp in morphine-treated and control rats were compared by qRT-PCR and western blotting. The levels of Mdr1a and Bcrp mRNAs were not significantly modified 6 h post morphine, but the Mdr1a mRNA increased 1.4-fold and Bcrp mRNA 2.4-fold at 24 h. P-gp and Bcrp protein expression in brain microvessels was unchanged 6 h post morphine and increased 1.5-fold at 24 h. This effect was more pronounced in large vessels than in microvessels. However, extracellular morphine concentrations of 0.01-10 ?M did not modify the expressions of the MDR1 and BCRP genes in hCMEC/D3 human endothelial brain cells in vitro. MK-801 (NMDA antagonist) and meloxicam (cyclo-oxygenase-2 inhibitor) given after morphine treatment completely blocked P-gp and Bcrp up-regulation. Interestingly, misoprostol and iloprost, two well-known agonists of prostaglandin E2 receptors induced both MDR1 and BCRP mRNA levels in hCMEC/D3. Thus, morphine does not directly stimulate P-gp and Bcrp expression by the brain endothelium, but glutamate released during morphine withdrawal may do so by activating the NMDA/cyclo-oxygenase-2 cascade.

PMID: 22845665 [PubMed - indexed for MEDLINE]

zm-447439 rad001 ecdysone

New insights into the roles of ATM and DNA-PKcs in the cellular response to oxidative stress.

Related Articles

New insights into the roles of ATM and DNA-PKcs in the cellular response to oxidative stress.

Cancer Lett. 2012 Dec 31;327(1-2):103-10

Authors: Chen BP, Li M, Asaithamby A

Abstract
Reactive oxygen species (ROS) are induced by a variety of endogenous and exogenous sources. At pathologically high levels, ROS cause damage to biological molecules, including DNA. The damage sustained by DNA likely plays a key role in the pathogenesis of aging and carcinogenesis. Extensive research has established in detail the mechanism of cellular response to oxidative stress. Attention is now focused on identifying the molecular contributions of the key DNA damage response kinases ataxia telangiectasia mutated (ATM), DNA-dependent protein kinase catalytic subunit (DNA-PKcs), and ATM- and Rad3-related (ATR) in the oxidative stress response. In this review, we will provide an update of the current evidence regarding the involvement of these related DNA damage response kinases in oxidative DNA lesion repair and signaling responses. The growing understanding of the involvement of ATM, DNA-PKcs, and ATR in the oxidative stress response will offer new possibilities for the treatment of ROS-related diseases.

PMID: 22155347 [PubMed - indexed for MEDLINE]

dovitinib dna-pk coxinhibitors

Clinical application of development of nonantibiotic macrolides that correct inflammation-driven immune dysfunction in inflammatory skin diseases.

Clinical application of development of nonantibiotic macrolides that correct inflammation-driven immune dysfunction in inflammatory skin diseases.

Mediators Inflamm. 2012;2012:563709

Authors: Rodriguez-Cerdeira C, Sanchez-Blanco E, Molares-Vila A

Abstract
Background. Inflammation-driven immune dysfunction supports the development of several chronic human disorders including skin diseases. Nonantibiotic macrolides have anti-inflammatory and/or immunomodulatory activity that suggests the exploitation of these in the treatment of skin diseases characterized by inflammatory disorders. Materials and Methods. We performed an extensive review of the nonantibiotic macrolide literature published between 2005 and 2012, including cross-references of any retrieved articles. We also included some data from our own experience. Results. Calcineurin antagonists such as tacrolimus and ascomycins (e.g., pimecrolimus) act by inhibiting the activation of the nuclear factor for activated T cells (NFAT). There are new applications for these macrolides that have been available for several years and have been applied to skin and hair disorders such as atopic dermatitis, oral lichen planus, vitiligo, chronic autoimmune urticaria, rosacea, alopecia areata, pyoderma gangrenosum, Behcet's disease, neutrophilic dermatosis, and lupus erythematosus. We also reviewed new macrolides, like rapamycin, everolimus, and temsirolimus. In addition to the literature review, we report a novel class of nonantibiotic 14-member macrocycle with anti-inflammatory and immunomodulatory effects. Conclusions. This paper summarizes the most important clinical studies and case reports dealing with the potential benefits of nonantibiotic macrolides which have opened new avenues in the development of anti-inflammatory strategies in the treatment of cutaneous disorders.

PMID: 23258954 [PubMed - in process]

c-met inhibitors zm-447439 rad001

Clinical application of development of nonantibiotic macrolides that correct inflammation-driven immune dysfunction in inflammatory skin diseases.

Clinical application of development of nonantibiotic macrolides that correct inflammation-driven immune dysfunction in inflammatory skin diseases.

Mediators Inflamm. 2012;2012:563709

Authors: Rodriguez-Cerdeira C, Sanchez-Blanco E, Molares-Vila A

Abstract
Background. Inflammation-driven immune dysfunction supports the development of several chronic human disorders including skin diseases. Nonantibiotic macrolides have anti-inflammatory and/or immunomodulatory activity that suggests the exploitation of these in the treatment of skin diseases characterized by inflammatory disorders. Materials and Methods. We performed an extensive review of the nonantibiotic macrolide literature published between 2005 and 2012, including cross-references of any retrieved articles. We also included some data from our own experience. Results. Calcineurin antagonists such as tacrolimus and ascomycins (e.g., pimecrolimus) act by inhibiting the activation of the nuclear factor for activated T cells (NFAT). There are new applications for these macrolides that have been available for several years and have been applied to skin and hair disorders such as atopic dermatitis, oral lichen planus, vitiligo, chronic autoimmune urticaria, rosacea, alopecia areata, pyoderma gangrenosum, Behcet's disease, neutrophilic dermatosis, and lupus erythematosus. We also reviewed new macrolides, like rapamycin, everolimus, and temsirolimus. In addition to the literature review, we report a novel class of nonantibiotic 14-member macrocycle with anti-inflammatory and immunomodulatory effects. Conclusions. This paper summarizes the most important clinical studies and case reports dealing with the potential benefits of nonantibiotic macrolides which have opened new avenues in the development of anti-inflammatory strategies in the treatment of cutaneous disorders.

PMID: 23258954 [PubMed - in process]

coxinhibitors c-met inhibitors zm-447439

Improvement of pest resistance in transgenic tobacco plants expressing dsRNA of an insect-associated gene EcR.

Related Articles

Improvement of pest resistance in transgenic tobacco plants expressing dsRNA of an insect-associated gene EcR.

PLoS One. 2012;7(6):e38572

Authors: Zhu JQ, Liu S, Ma Y, Zhang JQ, Qi HS, Wei ZJ, Yao Q, Zhang WQ, Li S

Abstract
The adoption of pest-resistant transgenic plants to reduce yield loss and pesticide utilization has been successful in the past three decades. Recently, transgenic plant expressing double-stranded RNA (dsRNA) targeting pest genes emerges as a promising strategy for improving pest resistance in crops. The steroid hormone, 20-hydroxyecdysone (20E), predominately controls insect molting via its nuclear receptor complex, EcR-USP. Here we report that pest resistance is improved in transgenic tobacco plants expressing dsRNA of EcR from the cotton bollworm, Helicoverpa armigera, a serious lepidopteran pest for a variety of crops. When H. armigera larvae were fed with the whole transgenic tobacco plants expressing EcR dsRNA, resistance to H. armigera was significantly improved in transgenic plants. Meanwhile, when H. armigera larvae were fed with leaves of transgenic tobacco plants expressing EcR dsRNA, its EcR mRNA level was dramatically decreased causing molting defects and larval lethality. In addition, the transgenic tobacco plants expressing H. armigera EcR dsRNA were also resistant to another lepidopteran pest, the beet armyworm, Spodoptera exigua, due to the high similarity in the nucleotide sequences of their EcR genes. This study provides additional evidence that transgenic plant expressing dsRNA targeting insect-associated genes is able to improve pest resistance.

PMID: 22685585 [PubMed - indexed for MEDLINE]

dovitinib dna-pk coxinhibitors

A validated tumorgraft model reveals activity of dovitinib against renal cell carcinoma.

Related Articles

A validated tumorgraft model reveals activity of dovitinib against renal cell carcinoma.

Sci Transl Med. 2012 Jun 6;4(137):137ra75

Authors: Sivanand S, Pe�a-Llopis S, Zhao H, Kucejova B, Spence P, Pavia-Jimenez A, Yamasaki T, McBride DJ, Gillen J, Wolff NC, Morlock L, Lotan Y, Raj GV, Sagalowsky A, Margulis V, Cadeddu JA, Ross MT, Bentley DR, Kabbani W, Xie XJ, Kapur P, Williams NS, Brugarolas J

Abstract
Most anticancer drugs entering clinical trials fail to achieve approval from the U.S. Food and Drug Administration. Drug development is hampered by the lack of preclinical models with therapeutic predictive value. Herein, we report the development and validation of a tumorgraft model of renal cell carcinoma (RCC) and its application to the evaluation of an experimental drug. Tumor samples from 94 patients were implanted in the kidneys of mice without additives or disaggregation. Tumors from 35 of these patients formed tumorgrafts, and 16 stable lines were established. Samples from metastatic sites engrafted at higher frequency than those from primary tumors, and stable engraftment of primary tumors in mice correlated with decreased patient survival. Tumorgrafts retained the histology, gene expression, DNA copy number alterations, and more than 90% of the protein-coding gene mutations of the corresponding tumors. As determined by the induction of hypercalcemia in tumorgraft-bearing mice, tumorgrafts retained the ability to induce paraneoplastic syndromes. In studies simulating drug exposures in patients, RCC tumorgraft growth was inhibited by sunitinib and sirolimus (the active metabolite of temsirolimus in humans), but not by erlotinib, which was used as a control. Dovitinib, a drug in clinical development, showed greater activity than sunitinib and sirolimus. The routine incorporation of models recapitulating the molecular genetics and drug sensitivities of human tumors into preclinical programs has the potential to improve oncology drug development.

PMID: 22674553 [PubMed - indexed for MEDLINE]

chir-258 dovitinib dna-pk

New insights into the roles of ATM and DNA-PKcs in the cellular response to oxidative stress.

Related Articles

New insights into the roles of ATM and DNA-PKcs in the cellular response to oxidative stress.

Cancer Lett. 2012 Dec 31;327(1-2):103-10

Authors: Chen BP, Li M, Asaithamby A

Abstract
Reactive oxygen species (ROS) are induced by a variety of endogenous and exogenous sources. At pathologically high levels, ROS cause damage to biological molecules, including DNA. The damage sustained by DNA likely plays a key role in the pathogenesis of aging and carcinogenesis. Extensive research has established in detail the mechanism of cellular response to oxidative stress. Attention is now focused on identifying the molecular contributions of the key DNA damage response kinases ataxia telangiectasia mutated (ATM), DNA-dependent protein kinase catalytic subunit (DNA-PKcs), and ATM- and Rad3-related (ATR) in the oxidative stress response. In this review, we will provide an update of the current evidence regarding the involvement of these related DNA damage response kinases in oxidative DNA lesion repair and signaling responses. The growing understanding of the involvement of ATM, DNA-PKcs, and ATR in the oxidative stress response will offer new possibilities for the treatment of ROS-related diseases.

PMID: 22155347 [PubMed - indexed for MEDLINE]

zm-447439 rad001 ecdysone

Improvement of pest resistance in transgenic tobacco plants expressing dsRNA of an insect-associated gene EcR.

Related Articles

Improvement of pest resistance in transgenic tobacco plants expressing dsRNA of an insect-associated gene EcR.

PLoS One. 2012;7(6):e38572

Authors: Zhu JQ, Liu S, Ma Y, Zhang JQ, Qi HS, Wei ZJ, Yao Q, Zhang WQ, Li S

Abstract
The adoption of pest-resistant transgenic plants to reduce yield loss and pesticide utilization has been successful in the past three decades. Recently, transgenic plant expressing double-stranded RNA (dsRNA) targeting pest genes emerges as a promising strategy for improving pest resistance in crops. The steroid hormone, 20-hydroxyecdysone (20E), predominately controls insect molting via its nuclear receptor complex, EcR-USP. Here we report that pest resistance is improved in transgenic tobacco plants expressing dsRNA of EcR from the cotton bollworm, Helicoverpa armigera, a serious lepidopteran pest for a variety of crops. When H. armigera larvae were fed with the whole transgenic tobacco plants expressing EcR dsRNA, resistance to H. armigera was significantly improved in transgenic plants. Meanwhile, when H. armigera larvae were fed with leaves of transgenic tobacco plants expressing EcR dsRNA, its EcR mRNA level was dramatically decreased causing molting defects and larval lethality. In addition, the transgenic tobacco plants expressing H. armigera EcR dsRNA were also resistant to another lepidopteran pest, the beet armyworm, Spodoptera exigua, due to the high similarity in the nucleotide sequences of their EcR genes. This study provides additional evidence that transgenic plant expressing dsRNA targeting insect-associated genes is able to improve pest resistance.

PMID: 22685585 [PubMed - indexed for MEDLINE]

chir-258 dovitinib dna-pk

Licofelone inhibits interleukin-18-induced pro-inflammatory cytokine release and cellular proliferation in human mesangial cells.

Related Articles

Licofelone inhibits interleukin-18-induced pro-inflammatory cytokine release and cellular proliferation in human mesangial cells.

Basic Clin Pharmacol Toxicol. 2012 Sep;111(3):166-72

Authors: Wu YJ, Xue M, Chen H

Abstract
Licofelone, a novel dual anti-inflammatory drug that inhibits 5-lipoxygenase (5-LOX) and cyclooxygenase (COX), has recently been defined to have therapeutic effects in osteoarthritis. Both 5-LOX and COX play functional roles in the pathogenesis of glomerulonephritis in children as well. Interleukin-18 is a pro-inflammatory cytokine. It remains unclear whether licofelone can ameliorate inflammatory response of human mesangial cells (HMC) exposed to interleukin-18. In this study, HMC were cultured and exposed to interleukin-18 with or without pre-treatment of licofelone. COX-2 and 5-LOX enzyme activities in mesangial cells were determined with chromometry or high-performance liquid chromatography. Prostaglandin E2, cysteinyl leukotriene, monocyte chemotactic protein-1 and interferon-? concentrations in culture medium were measured using an enzyme-linked immunosorbent assay. Western blotting was employed to detect phosphorylated mitogen-activated protein kinases ERK1/2, p38 and JNK1/2 in HMC. It was found that licofelone attenuated interleukin-18-induced COX-2 enzyme activity in HMC and prostaglandin E2 release in a dose-dependent manner. Similarly, licofelone inhibited interleukin-18-induced 5-LOX enzyme activity and leukotriene release. Licofelone reduced interleukin-18-induced phosphorylation of p38 mitogen-activated protein kinase and suppressed monocyte chemotactic protein-1 and interferon-? synthesis. Moreover, licofelone inhibited IL-18-induced proliferation of mesangial cells. We conclude that licofelone inhibits interleukin-18-induced pro-inflammatory cytokine release and cellular proliferation in HMC, which may represent a really interesting therapeutic approach for glomerulonephritis in children.

PMID: 22433003 [PubMed - indexed for MEDLINE]

coxinhibitors c-met inhibitors zm-447439

New insights into the roles of ATM and DNA-PKcs in the cellular response to oxidative stress.

Related Articles

New insights into the roles of ATM and DNA-PKcs in the cellular response to oxidative stress.

Cancer Lett. 2012 Dec 31;327(1-2):103-10

Authors: Chen BP, Li M, Asaithamby A

Abstract
Reactive oxygen species (ROS) are induced by a variety of endogenous and exogenous sources. At pathologically high levels, ROS cause damage to biological molecules, including DNA. The damage sustained by DNA likely plays a key role in the pathogenesis of aging and carcinogenesis. Extensive research has established in detail the mechanism of cellular response to oxidative stress. Attention is now focused on identifying the molecular contributions of the key DNA damage response kinases ataxia telangiectasia mutated (ATM), DNA-dependent protein kinase catalytic subunit (DNA-PKcs), and ATM- and Rad3-related (ATR) in the oxidative stress response. In this review, we will provide an update of the current evidence regarding the involvement of these related DNA damage response kinases in oxidative DNA lesion repair and signaling responses. The growing understanding of the involvement of ATM, DNA-PKcs, and ATR in the oxidative stress response will offer new possibilities for the treatment of ROS-related diseases.

PMID: 22155347 [PubMed - indexed for MEDLINE]

rad001 ecdysone chir-258