701
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Stolfi C, Fina D, Caruso R, Caprioli F, Fantini MC, Rizzo A, Sarra M, Pallone F, Monteleone G. Mesalazine negatively regulates CDC25A protein expression and promotes accumulation of colon cancer cells in S phase. Carcinogenesis 2008; 29:1258-66. [DOI: 10.1093/carcin/bgn122] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
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702
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Cycles within cycles. Menopause 2008; 15:412-3. [PMID: 18391835 DOI: 10.1097/gme.0b013e31816f70bd] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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703
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Martinez-Perez E, Moore G. To check or not to check? The application of meiotic studies to plant breeding. CURRENT OPINION IN PLANT BIOLOGY 2008; 11:222-7. [PMID: 18294901 DOI: 10.1016/j.pbi.2008.01.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2007] [Revised: 01/02/2008] [Accepted: 01/03/2008] [Indexed: 05/08/2023]
Abstract
Understanding the barriers that prevent pairing and recombination of the chromosomes from two parental species is important for crop improvement strategies. It had been generally thought that plants do not possess checkpoint mechanisms during meiosis. However, recent data may question this assumption and suggest that exploitation of such mechanisms could be crucial to breeding.
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Affiliation(s)
- Enrique Martinez-Perez
- Department of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, Sheffield S10 2TN, UK.
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704
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Liu L, Schwartz B, Tsubota Y, Raines E, Kiyokawa H, Yonekawa K, Harlan JM, Schnapp LM. Cyclin-dependent kinase inhibitors block leukocyte adhesion and migration. THE JOURNAL OF IMMUNOLOGY 2008; 180:1808-17. [PMID: 18209078 DOI: 10.4049/jimmunol.180.3.1808] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Leukocyte trafficking is a tightly regulated process essential for an appropriate inflammatory response. We now report a new adhesion pathway that allows unstimulated leukocytes to adhere to and migrate through exposed endothelial matrix or high-density ligand, a process we have termed ligand-induced adhesion. This ligand-induced adhesion is integrin mediated, but in contrast to phorbol ester-stimulated adhesion, it is not dependent on the small GTPase Rap-1 activity. Instead, we show a critical role for cyclin-dependent kinase (Cdk) 4 in ligand-induced adhesion by three independent lines of evidence: inhibition by pharmacological inhibitors of Cdk, inhibition by dominant-negative construct of Cdk4, and inhibition by Cdk4 small interfering RNA. The major substrate of Cdk4, Rb, is not required for ligand-induced adhesion, suggesting the involvement of a novel Cdk4 substrate. We also demonstrate that Cdk4(-/-) mice have impaired recruitment of lymphocytes to the lung following injury. The finding that Cdk inhibitors can block leukocyte adhesion and migration may expand the clinical indications for this emerging class of therapeutics.
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Affiliation(s)
- Li Liu
- Division of Hematology, Department of Medicine, University of Washington, Seattle, WA 98104, USA
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705
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Lee J, Choi H, Kim KH, Jeong S, Park JW, Baek CS, Lee SH. Synthesis and biological evaluation of 3,5-diaminoindazoles as cyclin-dependent kinase inhibitors. Bioorg Med Chem Lett 2008; 18:2292-5. [PMID: 18353638 DOI: 10.1016/j.bmcl.2008.03.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2007] [Revised: 02/29/2008] [Accepted: 03/03/2008] [Indexed: 11/15/2022]
Abstract
A novel series of 3,5-diaminoindazoles were prepared and found to be CDK inhibitors. Potent inhibitors against CDK1 and CDK2 were obtained by introduction of 1lambda(6)-isothiazolidine-1,1-dioxide at 5-position of indazole. Anti-proliferative activities of compounds were evaluated using EJ, HCT116, SW620, and A549 cancer cell lines.
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Affiliation(s)
- Jinho Lee
- Department of Chemistry, Keimyung University, 1000 Sindang-Dong, Dalseo-Gu, Daegu 704-701, South Korea.
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706
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Rixe O, Fojo T. Is cell death a critical end point for anticancer therapies or is cytostasis sufficient? Clin Cancer Res 2008; 13:7280-7. [PMID: 18094408 DOI: 10.1158/1078-0432.ccr-07-2141] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Since the discovery of conventional chemotherapy and the development of new target-based agents, the importance of cytostasis in anticancer activity has been debated. This review examines the relative importance of both cytostasis and cytotoxicity based on both preclinical data and clinical reports. Several limitations of our basic and clinical methods to evaluate cytostasis and cytotoxicity will be highlighted. Molecular mechanisms of cytostasis will be analyzed, including interference with the cell cycle as well as putative links with necrosis and autophagy. Finally, we will cite evidence that most older and newer compounds are both cytostatic and cytotoxic. The relative role of cytostasis and cytotoxicity on future drug screening and clinical development will be explored.
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Affiliation(s)
- Olivier Rixe
- Medical Oncology Department of the Salpêtrière Hospital, Pierre and Marie Curie University, Paris, France.
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707
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Freemantle SJ, Liu X, Feng Q, Galimberti F, Blumen S, Sekula D, Kitareewan S, Dragnev KH, Dmitrovsky E. Cyclin degradation for cancer therapy and chemoprevention. J Cell Biochem 2008; 102:869-77. [PMID: 17868090 DOI: 10.1002/jcb.21519] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cancer is characterized by uncontrolled cell division resulting from multiple mutagenic events. Cancer chemoprevention strategies aim to inhibit or reverse these events using natural or synthetic pharmacologic agents. Ideally, this restores normal growth control mechanisms. Diverse classes of compounds have been identified with chemopreventive activity. What unites many of them is an ability to inhibit the cell cycle by specifically modulating key components. This delays division long enough for cells to respond to mutagenic damage. In some cases, damage is repaired and in others cellular damage is sufficient to trigger apoptosis. It is now known that pathways responsible for targeting G1 cyclins for proteasomal degradation can be engaged pharmacologically. Emergence of induced cyclin degradation as a target for cancer therapy and chemoprevention in pre-clinical models is discussed in this article. Evidence for cyclin D1 as a molecular pharmacologic target and biological marker for clinical response is based on experience of proof of principle trials.
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Affiliation(s)
- Sarah J Freemantle
- Department of Pharmacology and Toxicology, Dartmouth Medical School, Hanover, New Hampshire 03755, USA.
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708
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Balk SP, Knudsen KE. AR, the cell cycle, and prostate cancer. NUCLEAR RECEPTOR SIGNALING 2008; 6:e001. [PMID: 18301781 PMCID: PMC2254330 DOI: 10.1621/nrs.06001] [Citation(s) in RCA: 239] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2007] [Accepted: 12/07/2007] [Indexed: 01/17/2023]
Abstract
The androgen receptor (AR) is a critical effector of prostate cancer development and progression. The dependence of this tumor type on AR activity is exploited in treatment of disseminated prostate cancers, wherein ablation of AR function (achieved either through ligand depletion and/or the use of AR antagonists) is the first line of therapeutic intervention. These strategies are initially effective, and induce a mixed response of cell cycle arrest or apoptosis in prostate cancer cells. However, recurrent, incurable tumors ultimately arise as a result of inappropriately restored AR function. Based on these observations, it is imperative to define the mechanisms by which AR controls cancer cell proliferation. Mechanistic investigation has revealed that AR acts as a master regulator of G1-S phase progression, able to induce signals that promote G1 cyclin-dependent kinase (CDK) activity, induce phosphorylation/inactivation of the retinoblastoma tumor suppressor (RB), and thereby govern androgen-dependent proliferation. These functions appear to be independent of the recently identified TMPRSS2-ETS fusions. Once engaged, several components of the cell cycle machinery actively modulate AR activity throughout the cell cycle, thus indicating that crosstalk between the AR and cell cycle pathways likely modulate the mitogenic response to androgen. As will be discussed, discrete aberrations in this process can alter the proliferative response to androgen, and potentially subvert hormonal control of tumor progression.
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Affiliation(s)
- Steven P Balk
- Cancer Biology Program-Hematology Oncology Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
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709
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Echalier A, Bettayeb K, Ferandin Y, Lozach O, Clément M, Valette A, Liger F, Marquet B, Morris JC, Endicott JA, Joseph B, Meijer L. Meriolins (3-(pyrimidin-4-yl)-7-azaindoles): synthesis, kinase inhibitory activity, cellular effects, and structure of a CDK2/cyclin A/meriolin complex. J Med Chem 2008; 51:737-51. [PMID: 18232649 DOI: 10.1021/jm700940h] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report the synthesis and biological characterization of 3-(pyrimidin-4-yl)-7-azaindoles (meriolins), a chemical hybrid between the natural products meridianins and variolins, derived from marine organisms. Meriolins display potent inhibitory activities toward cyclin-dependent kinases (CDKs) and, to a lesser extent, other kinases (GSK-3, DYRK1A). The crystal structures of 1e (meriolin 5) and variolin B (Bettayeb, K.; Tirado, O. M.; Marionneau-Lambert, S.; Ferandin, Y.; Lozach, O.; Morris, J.; Mateo-Lozano, S.; Drückes, P.; Schächtele, C.; Kubbutat, M.; Liger, F.; Marquet, B.; Joseph, B.; Echalier, A.; Endicott, J.; Notario, V.; Meijer, L. Cancer Res. 2007, 67, 8325-8334) in complex with CDK2/cyclin A reveal that the two inhibitors are orientated in very different ways inside the ATP-binding pocket of the kinase. A structure-activity relationship provides further insight into the molecular mechanism of action of this family of kinase inhibitors. Meriolins are also potent antiproliferative and proapoptotic agents in cells cultured either as monolayers or in spheroids. Proapoptotic efficacy of meriolins correlates best with their CDK2 and CDK9 inhibitory activity. Meriolins thus constitute a promising class of pharmacological agents to be further evaluated against the numerous human diseases that imply abnormal regulation of CDKs including cancers, neurodegenerative disorders, and polycystic kidney disease.
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Affiliation(s)
- Aude Echalier
- Laboratory of Molecular Biophysics, Department of Biochemistry, The Rex Richards Building, University of Oxford, UK
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710
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Inoue S, Walewska R, Dyer MJS, Cohen GM. Downregulation of Mcl-1 potentiates HDACi-mediated apoptosis in leukemic cells. Leukemia 2008; 22:819-25. [PMID: 18239621 DOI: 10.1038/leu.2008.1] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Mcl-1 is an antiapoptotic Bcl-2 family member, whose degradation is supposedly required for the induction of apoptosis. However, histone deacetylase inhibitors (HDACi) induce apoptosis primarily through the Bak/Mcl-1/Noxa and Bim pathways without decreasing Mcl-1. To investigate this discrepancy, we examined the role of Mcl-1 on HDACi-mediated apoptosis. Inhibition of either class I or class II HDAC by selective HDACi caused an upregulation of Mcl-1 mRNA and protein. Downregulation of Mcl-1 by three structurally unrelated cyclin-dependent kinase inhibitors potentiated HDACi-mediated apoptosis in primary chronic lymphocytic leukemic (CLL) cells and K562 cells. Sensitivity to HDACi-induced apoptosis was increased approximately 10-fold by the cyclin-dependent kinase inhibitors. Nanomolar concentrations of HDACi, approximately 300-fold lower than that required to induce apoptosis alone, sensitized cells to TRAIL, emphasizing that the mechanism(s) whereby HDACi induce apoptosis is clearly distinct from those by which they sensitize to TRAIL. Furthermore, knockdown of Mcl-1-potentiated HDACi-mediated apoptosis in K562 cells. Thus, HDACi-mediated Mcl-1 upregulation plays an important antiapoptotic regulatory role in limiting the efficacy of HDACi-induced apoptosis, which can be overcome by combination with an agent that downregulates Mcl-1. Thus, a clinical trial in some cancers is warranted using a combination of an HDACi with agents that downregulate Mcl-1.
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Affiliation(s)
- S Inoue
- MRC Toxicology Unit, University of Leicester, Leicester, UK
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711
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Abstract
Rigorous quality control steps, termed checkpoints, tightly regulate progression through the cell cycle. DNA-damaging chemotherapy and radiation activate functional cellular checkpoints. These checkpoints can facilitate DNA repair and promote cell death in unrepaired cells. There are at least three DNA damage checkpoints - at G1/S, S, and G2/M - as well as a mitotic spindle checkpoint. Most cancer cells harbour mutations in tumour suppressors and/or oncogenes, which impair certain cell checkpoints. Inhibiting the remaining cell checkpoints - particularly after exposure of cancer cells to chemotherapy and/or radiation - allows cell death, a strategy now being employed in cancer therapeutics. With our increasing knowledge of cell cycle regulation, many compounds have been developed to inhibit specific checkpoint components, particularly at the G2/M transition. One such target is checkpoint kinase-1 (Chk1). We review here the molecular framework of the cell cycle, the rationale for targeting Chk1, the preclinical concepts related to the development of Chk1 inhibitors, and the efficacy and safety results from Chk1 inhibitors now in phase I/II trials.
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712
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Benesch M, Urban C. Liposomal cytarabine for leukemic and lymphomatous meningitis: recent developments. Expert Opin Pharmacother 2008; 9:301-9. [DOI: 10.1517/14656566.9.2.301] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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713
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Ohta K, Maruyama T, Uchida H, Ono M, Nagashima T, Arase T, Kajitani T, Oda H, Morita M, Yoshimura Y. Glycodelin blocks progression to S phase and inhibits cell growth: a possible progesterone-induced regulator for endometrial epithelial cell growth. Mol Hum Reprod 2008; 14:17-22. [PMID: 18178606 DOI: 10.1093/molehr/gam081] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Prolonged exposure to unopposed estrogen in the absence of progesterone gives rise to endometrial hyperplasia and carcinoma. Post-ovulatory progesterone is necessary for the proper growth and differentiation of endometrial epithelial cells (EECs). Progesterone exposure induces the endometrial production of numerous bioactive substances, one of which is the glycoprotein, glycodelin (Gd). We investigated the role of Gd in cell cycle progression and cell growth to better understand how Gd affects EEC behavior and endometrial cancer pathogenesis. Ishikawa cells, a well-differentiated human endometrial epithelial cancer cell line, were transfected with expression plasmids encoding enhanced green fluorescent protein (EGFP) or EGFP-fused Gd (EGFP-Gd). They were then subjected to a cell proliferation assay, flow cytometry cell cycle analysis and RT-PCR analysis of cyclin-dependent kinase inhibitors (CDKIs) including p21, p27 and p16. Overexpression of EGFP-Gd resulted in a reduction of cell proliferation activity, an accumulation of G1-phase cells and up-regulation of p21, p27 and p16 mRNAs. Furthermore, progesterone-induced inhibition of Ishikawa cell growth was partially attenuated by Gd knockdown using siRNA. These results indicate that Gd causes inhibition of G1/S progression together with up-regulation of CDKIs thereby reducing cell growth. Thus, progesterone-induced expression of Gd may, at least in part, contribute to the suppression of endometrial epithelial growth observed during the secretory phase.
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Affiliation(s)
- Kuniaki Ohta
- Department of Obstetrics and Gynecology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo 160-8582, Japan
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714
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Lorenzo HK, Susin SA. Therapeutic potential of AIF-mediated caspase-independent programmed cell death. Drug Resist Updat 2008; 10:235-55. [PMID: 18180198 DOI: 10.1016/j.drup.2007.11.001] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2007] [Accepted: 11/01/2007] [Indexed: 01/15/2023]
Abstract
Resistance to anticancer drugs is often related to deficient cell death execution pathways in cancer cells. Apoptosis, which denotes a form of cell death executed by caspases, was traditionally considered as the only physiological and programmed form of cell death. However, recent evidence indicates that programmed cell death (PCD) can occur in complete absence of caspase activation. Indeed, a large number of caspase-independent models are now defined and a key protein implicated in this type of PCD, apoptosis-inducing factor (AIF), has been identified. AIF is a mitochondrial protein with two faces looking in opposite life/death directions. Recently, the identification of five different isoforms allowed a better characterization of AIFs life/mitochondrial versus death/nuclear functions, as well as definition of its pro-apoptotic region and some of its nuclear partners. Importantly, much work on caspase-independent PCD has revealed that AIF participates in more PCD systems than initially thought. A wider molecular knowledge of AIF, and of the caspase-independent PCDs in which it is involved, are key to provide new insights into the role of PCD. There is no doubt that these insights will lead to the development of more selective and efficient drugs against cancer, degenerative diseases, and other pathological disorders implicating AIF.
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Affiliation(s)
- Hans K Lorenzo
- INSERM U542, Institut André Lwoff, Lavoisier Building, 94803 Villejuif, France.
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715
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CDK inhibitors in cancer therapy: what is next? Trends Pharmacol Sci 2008; 29:16-21. [DOI: 10.1016/j.tips.2007.10.012] [Citation(s) in RCA: 199] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2007] [Revised: 10/19/2007] [Accepted: 10/23/2007] [Indexed: 01/04/2023]
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716
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Anticancer Drug Discovery and Development. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 610:19-42. [DOI: 10.1007/978-0-387-73898-7_3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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717
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Fischmann TO, Hruza A, Duca JS, Ramanathan L, Mayhood T, Windsor WT, Le HV, Guzi TJ, Dwyer MP, Paruch K, Doll RJ, Lees E, Parry D, Seghezzi W, Madison V. Structure-guided discovery of cyclin-dependent kinase inhibitors. Biopolymers 2008; 89:372-9. [DOI: 10.1002/bip.20868] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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718
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Liu XN, Zhang CY, Jin XD, Li YZ, Zheng XZ, Li L. Inhibitory effect of schisandrin B on gastric cancer cells in vitro. World J Gastroenterol 2007; 13:6506-11. [PMID: 18161920 PMCID: PMC4611289 DOI: 10.3748/wjg.v13.i48.6506] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the inhibitory effect and possible mechanism of action of schisandrin B in SC-B on gastric cancer cells in vitro.
METHODS: SC-B consisted of schisandrin B, aloe-emodin, and Astragalus polysaccharides. Exponentially growing human gastric cancer SGC-7901 cells were divided into six treatment groups: (1) control group (RPMI 1640 medium); (2) negative control group (2% DMSO); (3) positive control group (50 mg/L 5-Fluorouracil, 5-FU); (4) low-dose group (LSC, final concentration of schisandrin B, 25 mg/L); (5) moderate-dose group (MSC, final concentration of schisandrin B, 50 mg/L); (6) high-dose group (HSC, final concentration of schisandrin B, 100 mg/L). Follow-up was done at 12-48 h. An MTT (Methylthiazolyldiphenyl-tetrazolium bromide) assay was used to examine the inhibitory effect of SC-B on gastric cancer cells. The mitosis index was assessed using an inverted microscope. Flow cytometry was used to visualize the cell cycle. An RT-PCR (Reverse transcription-Polymerase chain reaction) -based assay was used to detect mRNA expression for cyclin D1 and glyceraldehyde-3-phosphate dehydrogenase (GAPDH).
RESULTS: The MTT assay showed that the number of living cells in the LSC, MSC and HSC groups was significantly smaller than that in the DMSO-treated group (P < 0.05) at 12-48 h. The inhibitory rate (IR) of the LSC group was 41.15% ± 3.86%, 59.24% ± 5.34% and 69.93% ± 7.81% at 12, 24 and 48 h, respectively. The IR of the MSC group was 42.82% ± 4.94%, 62.68% ± 7.58% and 71.79% ± 8.12% at 12, 24 and 48 h, respectively. The IR of the HSC group was 37.50% ± 3.21%, 40.34% ± 2.98% and 61.99% ± 4.88% at 12, 24 and 48 h, respectively. These results suggested that a moderate dosage had the most obvious inhibitory efficacy at 48 h. Compared to the DMSO group, the mitosis index of the LSC, MSC, HSC groups was greatly decreased (P < 0.05) at all time points. Any dose of SC-B suppressed mitosis within 12-48 h. Compared to the DMSO group, the percentage of cells in the G0/G1 phase of the MSC group was greatly increased, and that of the S + G2M phase was greatly decreased, while the percentage of cell inhibition (PCI) in the MSC group was greatly increased (P < 0.05). This suggested that SC-B could exclusively arrest cells in the G0/G1 phase. Cyclin D1 mRNA expression was lower in the MSC group than that in the DMSO group (P < 0.05).
CONCLUSION: SC-B can inhibit the proliferation and aberrant mitosis of human gastric cancer SCG-7901 cells in vitro. This inhibitory effect may be due to the down-regulation of cyclin D1 mRNA expression, which causes cell cycle arrest of gastric cancer cells.
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719
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Mother Nature's gifts to diseases of man: the impact of natural products on anti-infective, anticholestemics and anticancer drug discovery. PROGRESS IN DRUG RESEARCH. FORTSCHRITTE DER ARZNEIMITTELFORSCHUNG. PROGRES DES RECHERCHES PHARMACEUTIQUES 2007; 65:1, 3-44. [PMID: 18084912 DOI: 10.1007/978-3-7643-8117-2_1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
This chapter is designed to demonstrate that compounds derived from nature are still in the forefront of drug discovery in diseases such as microbial and parasitic infections, carcinomas of many types and control of cholesterol/lipids in man. In each disease area we have provided short discussions of past, present and future agents, in general only considering compounds currently in clinical Phase II or later, that were/are derived from nature's chemical skeletons. Finishing with a discussion of the current and evolving role(s) of microbes (bacteria and fungi) in the production of old and new agents ostensibly produced by higher organisms.
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720
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Jackson RC, Barnett AL, McClue SJ, Green SR. Seliciclib, a cell-cycle modulator that acts through the inhibition of cyclin-dependent kinases. Expert Opin Drug Discov 2007; 3:131-43. [DOI: 10.1517/17460441.3.1.131] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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721
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Mechanisms of transcriptional regulation by MLL and its disruption in acute leukemia. Int J Hematol 2007; 87:10-8. [DOI: 10.1007/s12185-007-0009-8] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2007] [Accepted: 07/20/2007] [Indexed: 10/22/2022]
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722
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Ovcharenko D, Kelnar K, Johnson C, Leng N, Brown D. Genome-scale microRNA and small interfering RNA screens identify small RNA modulators of TRAIL-induced apoptosis pathway. Cancer Res 2007; 67:10782-8. [PMID: 18006822 DOI: 10.1158/0008-5472.can-07-1484] [Citation(s) in RCA: 171] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) binds to death receptors 4/5 and selectively induces caspase-dependent apoptosis. The RNA interference screening approach has led to the discovery and characterization of several TRAIL pathway components in human cells. Here, libraries of synthetic small interfering RNA (siRNA) and microRNAs (miRNA) were used to probe the TRAIL pathway. In addition to known genes, siRNAs targeting CDK4, PTGS1, ALG2, CLCN3, IRAK4, and MAP3K8 altered TRAIL-induced caspase-3 activation responses. Introduction of the miRNAs let-7c, mir-10a, mir-144, mir-150, mir-155, and mir-193 also affected the activation of the caspase cascade. Putative targets of these endogenous miRNAs included genes encoding death receptors, caspases, and other apoptosis-related genes. Among the novel genes revealed in the screen, CDK4 was selected for further characterization. CDK4 was the only member of the cyclin-dependent kinase gene family that bore a unique function in apoptotic signal transduction.
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723
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Heat Shock Protein B8, a Cyclin-Dependent Kinase–Independent Cyclin D1 Target Gene, Contributes to Its Effects on Radiation Sensitivity. Cancer Res 2007; 67:10774-81. [DOI: 10.1158/0008-5472.can-07-1475] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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724
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Le Tourneau C, Faivre S, Siu LL. Molecular targeted therapy of head and neck cancer: Review and clinical development challenges. Eur J Cancer 2007; 43:2457-66. [PMID: 17904355 DOI: 10.1016/j.ejca.2007.08.016] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2007] [Accepted: 08/17/2007] [Indexed: 11/27/2022]
Abstract
Recently, new targets have been identified in head and neck squamous cell carcinomas (HNSCC) as playing key roles in tumour proliferation and metastases. The first target that has led to the approval of a molecularly based therapy in HNSCC has been the epidermal growth factor receptor (EGFR). Indeed, cetuximab, a monoclonal antibody directed against EGFR, has recently been approved in combination with radiation therapy in patients with locally advanced HNSCC, and in patients with platinum-refractory recurrent or metastatic (R/M) HNSCC. This review discusses novel targeted anticancer agents that do not exclusively target EGFR. The initial assessments of novel agents have typically been in patients with heavily pre-treated R/M HNSCC, with response rates and times to progression that are often disappointing. Evaluation of novel agents in the pre-operative 'window' setting, or as first-line therapy for R/M disease, may offer a more optimal understanding of their molecular and clinical effects.
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725
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Bettayeb K, Tirado OM, Marionneau-Lambot S, Ferandin Y, Lozach O, Morris JC, Mateo-Lozano S, Drueckes P, Schächtele C, Kubbutat MHG, Liger F, Marquet B, Joseph B, Echalier A, Endicott JA, Notario V, Meijer L. Meriolins, a new class of cell death inducing kinase inhibitors with enhanced selectivity for cyclin-dependent kinases. Cancer Res 2007; 67:8325-34. [PMID: 17804748 DOI: 10.1158/0008-5472.can-07-1826] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Protein kinases represent promising anticancer drug targets. We describe here the meriolins, a new family of inhibitors of cyclin-dependent kinases (CDK). Meriolins represent a chemical structural hybrid between meridianins and variolins, two families of kinase inhibitors extracted from various marine invertebrates. Variolin B is currently in preclinical evaluation as an antitumor agent. A selectivity study done on 32 kinases showed that, compared with variolin B, meriolins display enhanced specificity toward CDKs, with marked potency on CDK2 and CDK9. The structures of pCDK2/cyclin A/variolin B and pCDK2/cyclin A/meriolin 3 complexes reveal that the two inhibitors bind within the ATP binding site of the kinase, but in different orientations. Meriolins display better antiproliferative and proapoptotic properties in human tumor cell cultures than their parent molecules, meridianins and variolins. Phosphorylation at CDK1, CDK4, and CDK9 sites on, respectively, protein phosphatase 1alpha, retinoblastoma protein, and RNA polymerase II is inhibited in neuroblastoma SH-SY5Y cells exposed to meriolins. Apoptosis triggered by meriolins is accompanied by rapid Mcl-1 down-regulation, cytochrome c release, and activation of caspases. Meriolin 3 potently inhibits tumor growth in two mouse xenograft cancer models, namely, Ewing's sarcoma and LS174T colorectal carcinoma. Meriolins thus constitute a new CDK inhibitory scaffold, with promising antitumor activity, derived from molecules initially isolated from marine organisms.
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Affiliation(s)
- Karima Bettayeb
- Centre National de la Recherche Scientifique, Cell Cycle Group & UPS2682, Station Biologique, Roscoff, Bretagne, France
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726
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James MK, Ray A, Leznova D, Blain SW. Differential modification of p27Kip1 controls its cyclin D-cdk4 inhibitory activity. Mol Cell Biol 2007; 28:498-510. [PMID: 17908796 PMCID: PMC2223302 DOI: 10.1128/mcb.02171-06] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Whether p27 is a cyclin D-cdk4/6 inhibitor or not is controversial, and how it might switch between these two modes is unknown. Arguing for a two-state mechanism, we show that p27 bound to cyclin D-cdk4 can be both inhibitory and noninhibitory, due to its differential-growth-state-dependent tyrosine phosphorylation. We found that p27 from proliferating cells was noninhibitory but that p27 from arrested cells was inhibitory, and the transition from a bound noninhibitor to a bound inhibitor was not due to an increase in p27 concentration. Rather, two tyrosine residues (Y88 and Y89) in p27's cdk interaction domain were phosphorylated preferentially in proliferating cells, which converted p27 to a noninhibitor. Concordantly, mutation of these sites rendered p27 resistant to phosphorylation and locked it into the bound-inhibitor mode in vivo and in vitro. Y88 was directly phosphorylated in vitro by the tyrosine kinase Abl, which converted p27 to a cdk4-bound noninhibitor. These data show that the growth-state-dependent tyrosine phosphorylation of p27 modulates its inhibitory activity in vivo.
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Affiliation(s)
- Melissa K James
- Department of Pediatrics, SUNY Downstate Medical Center, 450 Clarkson Ave., Box 49, Brooklyn, NY 11203, USA.
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727
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Wen-Xin L, Xi-Shan H. Application of laser capture microdissection and differential display technique for screening of pathogenic genes involved in endometrial carcinoma. Int J Gynecol Cancer 2007; 17:1224-30. [PMID: 17451460 DOI: 10.1111/j.1525-1438.2007.00947.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The objective is to eliminate the interference from other cell types; gene fragments involved in endometrial carcinoma (EC) are screened and cloned. Human normal endometrial glandular epithelia and EC cells were harvested with laser capture microdissection (LCM). The purification and concentration of minimal RNA were used to screen differential expressed gene fragments involved in EC by fluoro differential display polymerase chain reaction (FDD-PCR). The differential gene fragments were cloned, sequenced, and then identified by reverse Northern blot hybridization. Positive fragments were analyzed with basic local alignment search tool (BLAST). Cyclin-dependent kinase 7 (CDK7) expressions in EC and normal endometrial tissue were tested by immunohistochemical staining. Of 38 differential bands, 3 bands were of high expression in normal endometrium and 35 in EC. Six positive differential gene fragments were obtained and BLAST analysis for them suggested that L1.1 was homologous (99% identical) to the CDK7; L1.9 had a 99% homology with protein phosphatase 1 regulatory (inhibitor) subunit 12 A (PPP1R12A); L1.21 and L1.22 showed a 100% homology with cellular repressor of E1A-stimulated genes 1 (CREG); and L1.25 and L1.26 indicated more than 98% homology with solute carrier family 39 (zinc transporter), member 10 (SLC39A10). Immunohistochemistry revealed that CDK7 expression was higher in EC than in normal endometrium. We conclude that pathogenic genes involved in EC are obtained with LCM and FDD-PCR. It has been first found that CDK7, PPP1R12A, CREG, and SLC39A10 are correlative with EC from gene level. CDK7 is strongly associated with EC and can be used as potential molecular marker of EC for further studies
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Affiliation(s)
- L Wen-Xin
- Department of Gynecological Tumor, Affiliated Cancer Hospital, Tianjin Medical University, Tianjin, China.
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728
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Abstract
✓ Although advances in surgery, radiation therapy, and stereotactic radiosurgery have significantly improved the treatment of meningiomas, there remains an important subset of patients whose tumors are refractory to conventional therapy. Treatment with traditional chemotherapeutic agents has provided minimal benefit. In this review, the role of targeted molecular therapies for recurrent or progressive meningiomas is discussed.
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729
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Leary A, Johnston SRD. Small molecule signal transduction inhibitors for the treatment of solid tumors. Cancer Invest 2007; 25:347-65. [PMID: 17661211 DOI: 10.1080/07357900701259694] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A greater understanding of the pathogenesis of malignancy has led to the development of novel therapies designed to target aberrant molecular pathways that characterize and distinguish cancer cells from normal tissue. Small molecules are being designed to interfere with specific steps along the deregulated signaling cascade from the cytoplasmic membrane to the nucleus. Viable targets include growth factor receptors and their downstream second messengers, modulators of the cell cycle or apoptosis, regulators of protein trafficking and degradation, and transcription regulators. This review will discuss the small molecule signal transduction inhibitors in various stages of development and address the strategic issues relating to clinical trial design with these novel targeted agents.
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730
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Lv W, Chen L. Current status and recent developments in molecular targeted therapy against gastric cancer. Shijie Huaren Xiaohua Zazhi 2007; 15:2672-2678. [DOI: 10.11569/wcjd.v15.i25.2672] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Gastric cancer (GC) is one of the most common malignancies of the digestive system and is a major cause of cancer death in China. Recent improvements in both surgical techniques and adjuvant/neoadjuvant chemotherapy, radiotherapy or both have increased the survival rate of patients with early-stage disease. However, most patients with GC have advanced disease at diagnosis. Thus, despite recent advances, these patients still do poorly. Understanding the molecular pathways that characterize cell growth, cell cycle, apoptosis, angiogenesis and invasion has enabled us to use new approaches to treat this disease in clinical situations. These therapeutic strategies include epidermal growth factor receptor inhibitors, angiogenesis inhibitors, cell cycle inhibitors, apoptosis promoters and matrix metalloproteinase inhibitors. This review presents a brief introduction to the current status and advancement of molecular targeted therapies in the treatment of GC.
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731
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Dwyer MP, Paruch K, Alvarez C, Doll RJ, Keertikar K, Duca J, Fischmann TO, Hruza A, Madison V, Lees E, Parry D, Seghezzi W, Sgambellone N, Shanahan F, Wiswell D, Guzi TJ. Versatile templates for the development of novel kinase inhibitors: Discovery of novel CDK inhibitors. Bioorg Med Chem Lett 2007; 17:6216-9. [PMID: 17904366 DOI: 10.1016/j.bmcl.2007.09.018] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2007] [Revised: 08/31/2007] [Accepted: 09/05/2007] [Indexed: 10/22/2022]
Abstract
A series of four bicyclic cores were prepared and evaluated as cyclin-dependent kinase-2 (CDK2) inhibitors. From the in-vitro and cell-based analysis, the pyrazolo[1,5-a]pyrimidine core (represented by 9) emerged as the superior core for further elaboration in the identification of novel CDK2 inhibitors.
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Affiliation(s)
- Michael P Dwyer
- Schering-Plough Research Institute, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA.
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732
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Woodard CL, Keenan SM, Gerena L, Welsh WJ, Geyer JA, Waters NC. Evaluation of broad spectrum protein kinase inhibitors to probe the architecture of the malarial cyclin dependent protein kinase Pfmrk. Bioorg Med Chem Lett 2007; 17:4961-6. [PMID: 17588749 DOI: 10.1016/j.bmcl.2007.06.032] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2007] [Revised: 06/07/2007] [Accepted: 06/07/2007] [Indexed: 10/23/2022]
Abstract
We tested Pfmrk against several naphthalene and isoquinoline sulfonamides previously reported as protein kinase A (PKA) inhibitors. Pfmrk is a Cyclin Dependent protein Kinase (CDK) from Plasmodium falciparum, the causative parasite of the most lethal form of malaria. We find that the isoquinoline sulfonamides are potent inhibitors of Pfmrk and that substitution on the 5 position of the isoquinoline ring greatly influences the degree of potency. Molecular modeling studies suggest that the nitrogen atom in the isoquinoline ring plays a key role in ligand-receptor interactions. Structural analysis suggests that even subtle differences in amino acid composition within the active sites are responsible for conferring specificity of these inhibitors for Pfmrk over PKA.
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Affiliation(s)
- Cassandra L Woodard
- Division of Experimental Therapeutics, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA
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733
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Sugaya N, Ikeda K, Tashiro T, Takeda S, Otomo J, Ishida Y, Shiratori A, Toyoda A, Noguchi H, Takeda T, Kuhara S, Sakaki Y, Iwayanagi T. An integrative in silico approach for discovering candidates for drug-targetable protein-protein interactions in interactome data. BMC Pharmacol 2007; 7:10. [PMID: 17705877 PMCID: PMC2045083 DOI: 10.1186/1471-2210-7-10] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2007] [Accepted: 08/20/2007] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Protein-protein interactions (PPIs) are challenging but attractive targets for small chemical drugs. Whole PPIs, called the 'interactome', have been emerged in several organisms, including human, based on the recent development of high-throughput screening (HTS) technologies. Individual PPIs have been targeted by small drug-like chemicals (SDCs), however, interactome data have not been fully utilized for exploring drug targets due to the lack of comprehensive methodology for utilizing these data. Here we propose an integrative in silico approach for discovering candidates for drug-targetable PPIs in interactome data. RESULTS Our novel in silico screening system comprises three independent assessment procedures: i) detection of protein domains responsible for PPIs, ii) finding SDC-binding pockets on protein surfaces, and iii) evaluating similarities in the assignment of Gene Ontology (GO) terms between specific partner proteins. We discovered six candidates for drug-targetable PPIs by applying our in silico approach to original human PPI data composed of 770 binary interactions produced by our HTS yeast two-hybrid (HTS-Y2H) assays. Among them, we further examined two candidates, RXRA/NRIP1 and CDK2/CDKN1A, with respect to their biological roles, PPI network around each candidate, and tertiary structures of the interacting domains. CONCLUSION An integrative in silico approach for discovering candidates for drug-targetable PPIs was applied to original human PPIs data. The system excludes false positive interactions and selects reliable PPIs as drug targets. Its effectiveness was demonstrated by the discovery of the six promising candidate target PPIs. Inhibition or stabilization of the two interactions may have potential therapeutic effects against human diseases.
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Affiliation(s)
- Nobuyoshi Sugaya
- PharmaDesign, Inc., 2-19-8 Hatchobori, Chuo-ku, Tokyo, 104-0032, Japan
| | - Kazuyoshi Ikeda
- PharmaDesign, Inc., 2-19-8 Hatchobori, Chuo-ku, Tokyo, 104-0032, Japan
| | - Toshiyuki Tashiro
- PharmaDesign, Inc., 2-19-8 Hatchobori, Chuo-ku, Tokyo, 104-0032, Japan
| | - Shizu Takeda
- Central Research Laboratory, Hitachi, Ltd., 1-280 Higashi-koigakubo, Kokubunji-shi, Tokyo, 185-8601, Japan
| | - Jun Otomo
- Central Research Laboratory, Hitachi, Ltd., 1-280 Higashi-koigakubo, Kokubunji-shi, Tokyo, 185-8601, Japan
| | - Yoshiko Ishida
- Central Research Laboratory, Hitachi, Ltd., 1-280 Higashi-koigakubo, Kokubunji-shi, Tokyo, 185-8601, Japan
| | - Akiko Shiratori
- Central Research Laboratory, Hitachi, Ltd., 1-280 Higashi-koigakubo, Kokubunji-shi, Tokyo, 185-8601, Japan
| | - Atsushi Toyoda
- Genomic Sciences Center, RIKEN, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan
| | - Hideki Noguchi
- Genomic Sciences Center, RIKEN, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan
| | - Tadayuki Takeda
- Genomic Sciences Center, RIKEN, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan
| | - Satoru Kuhara
- Graduate School of Genetic Resources Technology, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka, 812-8581, Japan
| | - Yoshiyuki Sakaki
- Genomic Sciences Center, RIKEN, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa, 230-0045, Japan
| | - Takao Iwayanagi
- Research & Development Group, Hitachi, Ltd., 1-6-1 Marunouchi, Chiyoda-ku, Tokyo, 100-8220, Japan
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734
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Gomez LA, de Las Pozas A, Reiner T, Burnstein K, Perez-Stable C. Increased expression of cyclin B1 sensitizes prostate cancer cells to apoptosis induced by chemotherapy. Mol Cancer Ther 2007; 6:1534-43. [PMID: 17513602 DOI: 10.1158/1535-7163.mct-06-0727] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Chemotherapeutic drugs ideally should take advantage of the differences between transformed and normal cells and induce apoptosis only in cancer cells. One such difference may be the overexpression of cyclin B1 protein in cancer cells, which is required for the proper progression through mitosis. Previously, we showed that treatment of human prostate cancer cells with 2-methoxyestradiol (2-ME) or docetaxel results in an accumulation of cyclin B1 protein and an increase in cyclin B1 kinase activity, followed by induction of apoptotic cell death. Inhibition of cyclin B1 kinase lowers apoptosis induced by 2-ME and docetaxel. In this study, we established a positive correlation between cyclin B1 protein and apoptosis induced by chemotherapy in prostate cancer cells. There is minimal cyclin B1 and induction of apoptosis by chemotherapy in nontransformed cells. LNCaP and PC-3 prostate cancer cells stably overexpressing cyclin B1 are more sensitive to apoptosis induced by chemotherapy. LNCaP cells expressing cyclin B1 small interfering RNA to lower cyclin B1 protein or dominant negative cyclin-dependent kinase 1 to inhibit cyclin B1 kinase show a decrease in apoptosis. Increased sensitivity to apoptosis by overexpression of cyclin B1 may be due to lower Bcl-2, higher p53, and decreased neuroendocrine differentiation. We suggest that a cancer-specific mechanism whereby 2-ME and docetaxel may exert anti-prostate cancer activity is the deregulated activation of cyclin B1 kinase, leading to the induction of apoptotic cell death. Our results also suggest that higher levels of cyclin B1 in prostate cancer cells may be a good prognostic marker for chemotherapy.
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Affiliation(s)
- Lourdes A Gomez
- Geriatric Research, Education, and Clinical Center and Research Service, VA Medical Center, University of Miami Miller School of Medicine, 1201 Northwest 16 Street, Miami, FL 33125, USA
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735
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Ali MA, Choy H, Habib AA, Saha D. SNS-032 prevents tumor cell-induced angiogenesis by inhibiting vascular endothelial growth factor. Neoplasia 2007; 9:370-81. [PMID: 17534442 PMCID: PMC1877978 DOI: 10.1593/neo.07136] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2007] [Revised: 03/22/2007] [Accepted: 03/23/2007] [Indexed: 12/28/2022] Open
Abstract
Cell proliferation, migration, and capillary network formation of endothelial cells are the fundamental steps for angiogenesis, which involves the formation of new blood vessels. The purpose of this study is to investigate the effect of a novel aminothiazole SNS-032 on these critical steps for in vitro angiogenesis using a coculture system consisting of human umbilical vein endothelial cells (HUVECs) and human glioblastoma cells (U87MG). SNS-032 is a potent selective inhibitor of cyclin-dependent kinases 2, 7, and 9, and inhibits both transcription and cell cycle. In this study, we examined the proliferation and viability of HUVECs and U87MG cells in the presence of SNS-032 and observed a dose-dependent inhibition of cellular proliferation in both cell lines. SNS-032 inhibited threedimensional capillary network formations of endothelial cells. In a coculture study, SNS-032 completely prevented U87MG cell-mediated capillary formation of HUVECs. This inhibitor also prevented the migration of HUVECs when cultured alone or cocultured with U87MG cells. In addition, SNS-032 significantly prevented the production of vascular endothelial growth factor (VEGF) in both cell lines, whereas SNS-032 was less effective in preventing capillary network formation and migration of endothelial cells when an active recombinant VEGF was added to the medium. In conclusion, SNS-032 prevents in vitro angiogenesis, and this action is attributable to blocking of VEGF.
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Affiliation(s)
- M. Aktar Ali
- Division of Molecular Radiation Biology, Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9187, USA
| | - Hak Choy
- Division of Molecular Radiation Biology, Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9187, USA
| | - Amyn A Habib
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9187, USA
| | - Debabrata Saha
- Division of Molecular Radiation Biology, Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9187, USA
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736
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Abstract
Cdk7, a member of the cyclin dependent protein kinase family, regulates the activities of other Cdks through phosphorylation on their activation segment, and hence contributes to control of the eukaryotic cell cycle. Cdk7 is itself phosphorylated on the activation segment. Cdk7 phosphorylates Cdk1, Cdk2, Cdk4, and Cdk6, but only Cdk1 and Cdk2 can phosphorylate Cdk7 and none of them is able to auto-phosphorylate. The activation segments of the Cdks are very similar in sequence. Their specificity does not appear to be dictated by the sequences surrounding the phosphorylation sites but by structural determinants at remote sites. Through mutagenesis studies, we have identified regions in Cdk2 responsible for its interaction with Cdk7. A model has been built that explains the molecular basis for the specificity observed in Cdk recognition. The two kinases are arranged in a quasi-symmetric head-to-tail arrangement in which the N-terminal lobe from one kinase docks against the C-terminal lobe from the other kinase, and the activation segments are within reach of the opposite catalytic sites. Further experiments demonstrate that cyclin A hydrophobic pocket is not a recruitment site for Cdk7.
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Affiliation(s)
- Graziano Lolli
- Laboratory of Molecular Biophysics, Department of Biochemistry, University of Oxford, Oxford OX1 3QU, United Kingdom
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737
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Marchetti F, Sayle KL, Bentley J, Clegg W, Curtin NJ, Endicott JA, Golding BT, Griffin RJ, Haggerty K, Harrington RW, Mesguiche V, Newell DR, Noble MEM, Parsons RJ, Pratt DJ, Wang LZ, Hardcastle IR. Structure-based design of 2-arylamino-4-cyclohexylmethoxy-5-nitroso-6-aminopyrimidine inhibitors of cyclin-dependent kinase 2. Org Biomol Chem 2007; 5:1577-85. [PMID: 17571187 DOI: 10.1039/b703241b] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An efficient synthesis of 2-substituted O(4)-cyclohexylmethyl-5-nitroso-6-aminopyrimidines from 6-amino-2-mercaptopyrimidin-4-ol has been developed and used to prepare a range of derivatives for evaluation as inhibitors of cyclin-dependent kinase 2 (CDK2). The structure-activity relationships (SARs) are similar to those observed for the corresponding O(6)-cyclohexylmethoxypurine series with the 2-arylsulfonamide and 2-arylcarboxamide derivatives showing excellent potency. Two compounds, 4-(6-amino-4-cyclohexylmethoxy-5-nitrosopyrimidin-2-ylamino)-N-(2-hydroxyethyl)benzenesulfonamide (7q) and 4-(6-amino-4-cyclohexylmethoxy-5-nitrosopyrimidin-2-ylamino)-N-(2,3-dihydroxypropyl)benzenesulfonamide (7s), were the most potent with IC50 values of 0.7 +/- 0.1 and 0.8 +/- 0.0 nM against CDK2, respectively. The SARs determined in this study are discussed with reference to the crystal structure of 4-(6-amino-4-cyclohexylmethoxy-5-nitrosopyrimidin-2-ylamino)-N-(2,3-dihydroxypropyl)benzenesulfonamide (7j) bound to phosphorylated CDK2/cyclin A.
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Affiliation(s)
- Francesco Marchetti
- Northern Institute for Cancer Research, School of Natural Sciences-Chemistry, Bedson Building, Newcastle University, Newcastle Upon Tyne, UKNE1 7RU
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738
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Annis DA, Shipps GW, Deng Y, Popovici-Müller J, Siddiqui MA, Curran PJ, Gowen M, Windsor WT. Method for Quantitative Protein−Ligand Affinity Measurements in Compound Mixtures. Anal Chem 2007; 79:4538-42. [PMID: 17500537 DOI: 10.1021/ac0702701] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This manuscript describes an affinity selection-mass spectrometry (AS-MS) method for quantitative protein-ligand binding affinity (Kd) measurements in large compound libraries. The ability of a titrant ligand to displace a target-bound library member-as measured by MS-reveals the affinity ranking of the mixture component relative to "internal affinity calibrants", compounds of known affinity for the target. This technique does not require that the precise concentration of each ligand is known; therefore, unpurified products of mixture-based combinatorial synthesis may be used for affinity optimization and developing structure-activity relationships. The method is demonstrated for a series of ligands to the important oncology target CDK2 that were discovered by AS-MS screening of combinatorial libraries against the basal form of the protein. AS-MS displacement curves for select hits were acquired over a range of compound concentrations, confirming that binding affinity measurement results are concentration-insensitive. These hits were evaluated in pools of purified compounds to verify the method's applicability to hit triage in large chemical libraries. The method was further tested using unpurified, mixture-based combinatorial libraries of >1000 compounds, yielding results that mirror those obtained from mixtures of purified compounds. The technique was then used to identify optimized CDK2 ligands from compound mixtures, quantitatively measure their affinities, and establish structure-activity relationships among these drug leads.
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Affiliation(s)
- D Allen Annis
- Schering-Plough Research Institute, 320 Bent Street, Cambridge, Massachusetts 02141, USA.
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739
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Abstract
Advances in the understanding of glioma pathogenesis have led to increasing interest in the development of targeted molecular agents, and especially kinase inhibitors, for treatment of malignant gliomas. Protein kinases are a large family of enzymes that function as key regulators of cellular signaling pathways governing diverse functions, such as cell proliferation, growth, differentiation, invasion, angiogenesis and apoptosis in malignant gliomas. Preliminary clinical results with kinase inhibitors suggest that they are generally well-tolerated but have shown only modest activity. However, valuable information was obtained from these early clinical trials that will help the future development of these agents. This article reviews the important protein kinases in malignant gliomas, summarizes the existing clinical development of kinase inhibitors and discusses strategies to improve their effectiveness.
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Affiliation(s)
- Andrew S Chi
- Center For Neuro-Oncology, Dana-Farber/Brigham and Women's Cancer Center, Shields-Warren 430D, 44 Binney Street, Boston, MA 02115, USA
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740
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Chang MC, Chang YT, Sun CT, Chiu YF, Lin JT, Tien YW. Differential Expressions of Cyclin D1 Associated with Better Prognosis of Cancers of Ampulla of Vater. World J Surg 2007; 31:1135-41. [PMID: 17420962 DOI: 10.1007/s00268-006-0032-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
BACKGROUND Periampullary cancers, the incidence of which increases gradually with industrialization, still pose a significant challenge to clinicians and researchers. Specifically, the role of cell-cycle proteins and tumor suppressor genes in these cancers is not yet clear. Recent studies have revealed that genes and proteins related to cell cycle and apoptosis regulation may be involved in pancreatic carcinogenesis. METHODS Tissue samples were obtained from patients with periampullary cancers who underwent surgery at the National Taiwan University Hospital without receiving previous chemotherapy or radiation therapy. All periampullary cancer tissue samples were examined by a pathologist, who was unaware of the parameters to be investigated. A total of 68 patients with periampullary cancers (29 ampulla of Vater cancers (AVCs) and 39 pancreatic ductal cancers (PDCs), including various stages and histological subtypes, were enrolled. The relevant demographic and clinicopathological information was obtained from medical records. RESULTS Cell-cycle proteins, including p16, Rb, cyclin D1, p53, and E2F1, were analyzed by immunohistochemical staining. Here, significant differences were noted between AVCs and PDCs with regard to the expression of cyclin D1. This corresponded to a poor prognosis in PDCs (P < 0.05); AVCs, on the other hand, showed a relatively high survival rate. There is no obvious statistical difference between the 2 groups with regard to the expression of p16, Rb, p53, and E2F1. The study also revealed that cyclin D1 plays different roles in the carcinogenesis of AVCs and PDCs. CONCLUSIONS The expression of cyclin D1 is more often correlated with prognosis in AVCs than in PDCs, and may serve as a biomarker for the disease.
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Affiliation(s)
- Ming-Chug Chang
- Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, No. 7, Chung-Shan, South Road, Taipei, Taiwan, ROC
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741
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Joshi KS, Rathos MJ, Mahajan P, Wagh V, Shenoy S, Bhatia D, Chile S, Sivakumar M, Maier A, Fiebig HH, Sharma S. P276-00, a novel cyclin-dependent inhibitor induces G1-G2 arrest, shows antitumor activity on cisplatin-resistant cells and significant in vivo efficacy in tumor models. Mol Cancer Ther 2007; 6:926-34. [PMID: 17363487 DOI: 10.1158/1535-7163.mct-06-0614] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
P276-00, a flavone that inhibits cyclin-dependent kinases, has been identified by us recently as a novel antineoplastic agent. In this study, we have selected a panel of human tumor cell lines and xenografts to allow determination of selectivity and efficacy of P276-00. When tested against a panel of 16 cisplatin-sensitive and cisplatin-resistant cell lines, the antiproliferative potential of P276-00 was found to be approximately 30-fold higher than cisplatin. Studies to show tumor sensitivity using clonogenic assay in 22 human xenografts indicated that P276-00 was approximately 26-fold more potent than cisplatin, and further, it was also found to be active against cisplatin-resistant tumors of central nervous system, melanoma, prostate, and renal cancers. Further, we studied the effects of P276-00 on cell cycle progression by flow cytometry using asynchronous and synchronous population of tumor and normal cells. Asynchronous population of human prostate carcinoma (PC-3) and human promyelocytic leukemia (HL-60) cells when exposed to P276-00 showed arrest of slow-growing PC-3 cells in G(2)-M with no significant apoptosis observed up to 72 h. Unlike PC-3, significant apoptosis was seen in fast-growing HL-60 cells at 6 h. However, synchronized human non-small cell lung carcinoma (H-460) and human normal lung fibroblast (WI-38) cells showed arrest of cells in G(1). H-460 cells undergo apoptosis, which increases with longer exposure to the compound and also after exposure to P276-00 for 48 h followed by recovery. In contrast, the normal cells (WI-38) remain arrested in G(1) with no significant apoptosis up to 72 h of exposure and also after 48 h of P276-00 treatment followed by recovery, confirming our previous results that P276-00 was less effective against normal cells compared with cancer cells. After promising in vitro results, P276-00 was checked for in vivo efficacy in murine tumor and human xenograft models. Growth inhibition of murine colon cancer (CA-51) was significant when P276-00 was administered i.p. at 50 mg/kg daily for 20 treatments. However, in murine lung carcinoma model (Lewis lung), an increased dose of 60 mg/kg (30 mg/kg twice daily) administered every alternate day i.p. for seven treatments showed significant inhibition in the growth. Further studies were undertaken to establish the efficacy profile of P276-00 in human tumor xenograft models. In the two xenograft models studied, P276-00 showed potent in vivo antitumor potential. Compound P276-00 at a dose of 35 mg/kg administered daily via the i.p. route for 10 days showed significant (P < 0.05) inhibition in the growth of human colon carcinoma HCT-116 xenograft. Furthermore, P276-00 at a dose of 50 mg/kg once daily and 30 mg/kg twice daily administered via i.p. route for 20 treatments significantly (P < 0.05) inhibited growth of human non-small cell lung carcinoma H-460 xenograft. Thus, the in vitro cellular potency, together with in vivo antitumor activity, confirms the potential of P276-00, a cyclin-dependent kinase inhibitor as an anticancer molecule.
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Affiliation(s)
- Kalpana S Joshi
- Department of Pharmacology, Nicholas Piramal Research Center, Nicholas Piramal India Ltd., 1-Nirlon Complex, Goregaon (East), Mumbai 400 063, India.
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742
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Joshi KS, Rathos MJ, Joshi RD, Sivakumar M, Mascarenhas M, Kamble S, Lal B, Sharma S. In vitro antitumor properties of a novel cyclin-dependent kinase inhibitor, P276-00. Mol Cancer Ther 2007; 6:918-25. [PMID: 17363486 DOI: 10.1158/1535-7163.mct-06-0613] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cyclin-dependent kinases (Cdk) and their associated pathways represent some of the most attractive targets for the development of anticancer therapeutics. Based on antitumor activity in animal models, a variety of Cdk inhibitors are undergoing clinical evaluation either as a single agent or in combination with other approved drugs. In our anticancer drug discovery program, a novel series of flavones have been synthesized for evaluation against the activity of Cdk4-D1. This enzyme catalyzes the phosphorylation of retinoblastoma protein, thus inhibiting its function. We have identified a series of potent Cdk4-D1 inhibitors with IC(50) below 250 nmol/L. In this report, we have described the properties of one of the best compound, P276-00 of the flavone's series. P276-00 shows 40-fold selectivity toward Cdk4-D1, compared with Cdk2-E. The specificity toward 14 other related and unrelated kinases was also determined. P276-00 was found to be more selective with IC(50)s <100 nmol/L for Cdk4-D1, Cdk1-B, and Cdk9-T1, as compared with other Cdks, and less selective for non-Cdk kinases. It showed potent antiproliferative effects against various human cancer cell lines, with an IC(50) ranging from 300 to 800 nmol/L and was further compared for its antiproliferative activity against cancer and normal fibroblast cell lines. P276-00 was found to be highly selective for cancer cells as compared with normal fibroblast cells. To delineate its mechanism of action, the effect of P276-00 on cell cycle proteins was studied in human breast cancer cell line (MCF-7) and human non-small cell lung carcinoma (H-460). A significant down-regulation of cyclin D1 and Cdk4 and a decrease in Cdk4-specific pRb Ser(780) phosphorylation was observed. P276-00 produced potent inhibition of Cdk4-D1 activity that was found to be competitive with ATP and not with retinoblastoma protein. The compound also induced apoptosis in human promyelocytic leukemia (HL-60) cells, as evidenced by the induction of caspase-3 and DNA ladder studies. These data suggest that P276-00 has the potential to be developed as an anti-Cdk chemotherapeutic agent.
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Affiliation(s)
- Kalpana S Joshi
- Department of Pharmacology, Nicholas Piramal Research Center, Nicholas Piramal India Limited, 1-Nirlon Complex, Goregaon (E), Mumbai 400 063, India.
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743
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Gleissner B, Chamberlain M. Treatment of CNS dissemination in systemic lymphoma. J Neurooncol 2007; 84:107-17. [PMID: 17332946 DOI: 10.1007/s11060-007-9353-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2006] [Accepted: 02/06/2007] [Indexed: 11/25/2022]
Abstract
The frequency of central nervous system (CNS) dissemination in non-Hodgkin's lymphoma (NHL) varies and is dependent on NHL histology. More than 50% of patients with CNS involvement have advanced and progressive systemic disease. While CNS involvement at initial diagnosis may be treated curatively, treatment of CNS involvement in systemic relapsing or refractory lymphoma is challenging and most often palliative. Due to a paucity of randomized trials, treatment of lymphomatous metastases is not standardized. Nonetheless, treatment of LM entails administration of both CNS-directed and systemic chemotherapy that often includes high-dose chemotherapy regimens with stem cell support.
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Affiliation(s)
- B Gleissner
- Internal Medicine I, University Saarland, Homburg, Germany.
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744
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Filomeni G, Cerchiaro G, Da Costa Ferreira AM, De Martino A, Pedersen JZ, Rotilio G, Ciriolo MR. Pro-apoptotic activity of novel Isatin-Schiff base copper(II) complexes depends on oxidative stress induction and organelle-selective damage. J Biol Chem 2007; 282:12010-21. [PMID: 17327230 DOI: 10.1074/jbc.m610927200] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
We characterized the pro-apoptotic activity of two new synthesized isatin-Schiff base copper(II) complexes, obtained from isatin and 1,3-diaminopropane or 2-(2-aminoethyl)pyridine: (Cu(isapn)) and (Cu(isaepy)(2)), respectively. We demonstrated that these compounds trigger apoptosis via the mitochondrial pathway. The early induction of the p53/p21 system indicates a role for p53 in cell death, however, experiments carried out with small interfering RNA against p53, or with cells lacking p53, support that a p53-independent mechanism can also occur. The extent of apoptosis mirrors the kinetics of intracellular copper uptake. Particularly, Cu(isaepy)(2) enters the cells more efficiently and specifically damages nuclei and mitochondria, as evidenced by atomic absorption analysis of copper content and by the extent of nuclear and mitochondrial integrity. Conversely, Cu(isapn), although less permeable, induces a wide-spread oxidative stress, as demonstrated by analyses of reactive oxygen species concentration, and oxidation of proteins and lipids. The increase of the antioxidant defense, through the overexpression of Cu,Zn-SOD, partially counteracts cell death; whereas retinoic acid-mediated differentiation completely rescues cells from apoptosis induced by both compounds. The activation of JNK- and Akt-mediated phosphorylative pathways has been found to be not functional for apoptosis induction. On the contrary, apoptosis significantly decreased when the analogous zinc complex was used or when Cu(isaepy)(2) was incubated in the presence of a copper chelator. Altogether, our data provide evidence for a dual role of these copper(II) complexes: they are able to vehicle copper into the cell, thus producing reactive oxygen species, and could behave as delocalized lipophilic cation-like molecules, thus specifically targeting organelles.
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Affiliation(s)
- Giuseppe Filomeni
- Department of Biology, University of Rome "Tor Vergata," Via della Ricerca Scientifica, 00133 Rome, Italy
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745
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Mohapatra S, Coppola D, Riker AI, Pledger WJ. Roscovitine Inhibits Differentiation and Invasion in a Three-Dimensional Skin Reconstruction Model of Metastatic Melanoma. Mol Cancer Res 2007; 5:145-51. [PMID: 17314272 DOI: 10.1158/1541-7786.mcr-06-0300] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The aim of this study was to investigate the therapeutic potential of a cyclin-dependent kinase inhibitor, roscovitine, in cultured melanoma cells and a three-dimensional skin reconstruction model of metastatic melanoma. The modulatory effects of roscovitine on the growth and survival of normal melanocytes and cultured melanoma cell lines were tested. Additionally, we investigated the potential of roscovitine to regulate the growth and differentiation of a metastatic melanoma cell line (A375) in a three-dimensional skin reconstruction culture consisting of A375 cells admixed with normal human keratinocytes embedded within a collagen-constricted fibroblast matrix. We show that roscovitine is able to induce apoptosis in the melanoma cell lines A375, 888, and 624 but not in normal human cultured epithelial melanocytes. The degree of apoptosis within these cell lines correlated with the accumulation of p53 protein and concomitant reduction of X-linked inhibitor of apoptosis protein, with no change in the proteins Bcl-2 and survivin. We also found that roscovitine inhibited the growth and differentiation of A375 melanoma cells within the dermal layer of the skin. The results of this study show that roscovitine has the potential to inhibit the differentiation and invasion of metastatic melanoma and may be useful as a therapy for the treatment of patients with metastatic melanoma.
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Affiliation(s)
- Subhra Mohapatra
- Department of Interdisciplinary Oncology, H. Lee Moffitt Cancer Center and Research Institute and the University of South Florida Medical Center, 12902 Magnolia Drive, Tampa, FL 33612, USA.
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746
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DePinto W, Chu XJ, Yin X, Smith M, Packman K, Goelzer P, Lovey A, Chen Y, Qian H, Hamid R, Xiang Q, Tovar C, Blain R, Nevins T, Higgins B, Luistro L, Kolinsky K, Felix B, Hussain S, Heimbrook D. In vitro and in vivo activity of R547: a potent and selective cyclin-dependent kinase inhibitor currently in phase I clinical trials. Mol Cancer Ther 2007; 5:2644-58. [PMID: 17121911 DOI: 10.1158/1535-7163.mct-06-0355] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The cyclin-dependent protein kinases are key regulators of cell cycle progression. Aberrant expression or altered activity of distinct cyclin-dependent kinase (CDK) complexes results in escape of cells from cell cycle control, leading to unrestricted cell proliferation. CDK inhibitors have the potential to induce cell cycle arrest and apoptosis in cancer cells, and identifying small-molecule CDK inhibitors has been a major focus in cancer research. Several CDK inhibitors are entering the clinic, the most recent being selective CDK2 and CDK4 inhibitors. We have identified a diaminopyrimidine compound, R547, which is a potent and selective ATP-competitive CDK inhibitor. In cell-free assays, R547 effectively inhibited CDK1/cyclin B, CDK2/cyclin E, and CDK4/cyclin D1 (K(i) = 1-3 nmol/L) and was inactive (K(i) > 5,000 nmol/L) against a panel of >120 unrelated kinases. In vitro, R547 effectively inhibited the proliferation of tumor cell lines independent of multidrug resistant status, histologic type, retinoblastoma protein, or p53 status, with IC(50)s </= 0.60 mumol/L. The growth-inhibitory activity is characterized by a cell cycle block at G(1) and G(2) phases and induction of apoptosis. R547 reduced phosphorylation of the cellular retinoblastoma protein at specific CDK phosphorylation sites at the same concentrations that induced cell cycle arrest, suggesting a potential pharmacodynamic marker for clinical use. In vivo, R547 showed antitumor activity in all of the models tested to date, including six human tumor xenografts and an orthotopic syngeneic rat model. R547 was efficacious with daily oral dosing as well as with once weekly i.v. dosing in established human tumor models and at the targeted efficacious exposures inhibited phosphorylation of the retinoblastoma protein in the tumors. The selective kinase inhibition profile and the preclinical antitumor activity of R547 suggest that it may be promising for development for use in the treatment of solid tumors. R547 is currently being evaluated in phase I clinical trials.
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Affiliation(s)
- Wanda DePinto
- Discovery Oncology, Hoffmann-La Roche, Inc., 340 Kingsland Street, Nutley, NJ 07110, USA.
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747
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Neue Therapieansätze in der pädiatrischen Onkologie. Monatsschr Kinderheilkd 2007. [DOI: 10.1007/s00112-006-1454-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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748
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Malumbres M, Barbacid M. Cell cycle kinases in cancer. Curr Opin Genet Dev 2007; 17:60-5. [PMID: 17208431 DOI: 10.1016/j.gde.2006.12.008] [Citation(s) in RCA: 246] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2006] [Accepted: 12/20/2006] [Indexed: 02/07/2023]
Abstract
Cell division in mammalian cells is driven by protein kinases that regulate progression through the various phases of the cell cycle. Cyclin-dependent kinases (Cdks) regulate cell cycle commitment, DNA synthesis and the onset of mitosis. Kinases of the Aurora, Polo and Nek families participate in the centrosome cycle and modulate spindle function. Additional kinases such as Bub1, BubR1 and Mps1 regulate the spindle assembly checkpoint. It has been well established that misregulation of Cdks is one of the most frequent alterations in human cancer. Recent evidence indicates that mutations involving mitotic kinases are also linked to tumor development. These findings suggest novel strategies to use cell cycle kinases as targets for therapeutic intervention.
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Affiliation(s)
- Marcos Malumbres
- Cell Division and Cancer, Molecular Oncology Programme, Centro Nacional de Investigaciones Oncológicas (CNIO), 28029 Madrid, Spain
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749
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Karamouzis MV, Konstantinopoulos PA, Papavassiliou AG. The role of STATs in lung carcinogenesis: an emerging target for novel therapeutics. J Mol Med (Berl) 2007; 85:427-36. [PMID: 17216202 DOI: 10.1007/s00109-006-0152-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2006] [Revised: 11/29/2006] [Accepted: 11/29/2006] [Indexed: 01/02/2023]
Abstract
The signal transducer and activator of transcription (STAT) proteins are a family of latent cytoplasmic transcription factors, which form dimers when activated by cytokine receptors, tyrosine kinase growth factor receptors as well as non-receptor tyrosine kinases. Dimeric STATs translocate to the nucleus, where they bind to specific DNA-response elements in the promoters of target genes, thereby inducing unique gene expression programs often in association with other transcription regulatory proteins. The functional consequence of different STAT proteins activation varies, as their target genes play diverse roles in normal cellular/tissue functions, including growth, apoptosis, differentiation and angiogenesis. Certain activated STATs have been implicated in human carcinogenesis, albeit only few studies have focused into their role in lung tumours. Converging evidence unravels their molecular interplays and complex multipartite regulation, rendering some of them appealing targets for lung cancer treatment with new developing strategies.
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Affiliation(s)
- Michalis V Karamouzis
- Department of Biological Chemistry, Medical School, University of Athens, 75, M. Asias Street, 11527, Athens, Greece
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750
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Jee SB, Park WC, Kim KW, Kim JI, Ahn CH, Lim KW, Oh SJ, Song BJ, Jung SS, Kim JS. Methylation Patterns of Cancer-Associated Genes in Breast Cancer. J Breast Cancer 2007. [DOI: 10.4048/jbc.2007.10.1.51] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- Sung-Bae Jee
- Department of Surgery, The Catholic University of Korea, College of Medicine, Seoul, Korea
| | - Woo-Chan Park
- Department of Surgery, The Catholic University of Korea, College of Medicine, Seoul, Korea
| | - Kee-Whan Kim
- Department of Surgery, The Catholic University of Korea, College of Medicine, Seoul, Korea
| | - Ji-Il Kim
- Department of Surgery, The Catholic University of Korea, College of Medicine, Seoul, Korea
| | - Chang-Hyeok Ahn
- Department of Surgery, The Catholic University of Korea, College of Medicine, Seoul, Korea
| | - Keun-Woo Lim
- Department of Surgery, The Catholic University of Korea, College of Medicine, Seoul, Korea
| | - Se-Jung Oh
- Department of Surgery, The Catholic University of Korea, College of Medicine, Seoul, Korea
| | - Byung-Joo Song
- Department of Surgery, The Catholic University of Korea, College of Medicine, Seoul, Korea
| | - Sang-Seol Jung
- Department of Surgery, The Catholic University of Korea, College of Medicine, Seoul, Korea
| | - Jeong-Soo Kim
- Department of Surgery, The Catholic University of Korea, College of Medicine, Seoul, Korea
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