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Tsai TH. Analytical approaches for traditional chinese medicines exhibiting antineoplastic activity. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2001; 764:27-48. [PMID: 11817032 DOI: 10.1016/s0378-4347(01)00277-8] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Traditional Chinese medicines have attracted great interest in recent researchers as alternative antineoplastic therapies. This review focuses on analytical approaches to various aspects of the antineoplastic ingredients of traditional Chinese medicines. Emphasis will be put on the processes of biological sample extraction, separation, clean-up steps and the detection. The problems of the extraction solvent selection and different types of column chromatography are also discussed. The instruments considered are gas chromatography, capillary electrophoresis (CE) and high-performance liquid chromatography (HPLC) connected with various detectors (ultraviolet, fluorescence, electrochemistry, mass, etc.). In addition, determinations of antineoplastic herbal ingredients, including camptothecin, taxol (paclitaxel), vinblastine. vincristine, podophyllotoxin, colchicine, and their related compounds, such as irinotecan, SN-38, topotecan, 9-aminocamptothecin, docetaxel (taxotere) and etoposide, are briefly summarized. These drugs are structurally based on the herbal ingredients, and some of them are in trials for clinical use. Evaluation of potential antineoplastic herbal ingredients, such as harringtonine, berberine, emodin, genistein, berbamine, daphnoretin, and irisquinone, are currently investigated in laboratories. Other folk medicines are excluded from this paper because their antineoplastic ingredients are unknown.
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Affiliation(s)
- T H Tsai
- National Research Institute of Chinese Medicine, Taipei, Taiwan.
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102
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Bocca C, Gabriel L, Miglietta A. Cytoskeleton-interacting activity of geiparvarin, diethylstilbestrol and conjugates. Chem Biol Interact 2001; 137:285-305. [PMID: 11566295 DOI: 10.1016/s0009-2797(01)00261-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Geiparvarin, a natural compound isolated from the leaves of Geijera parviflora, inhibits the growth of various tumor cell lines with a mode of action which may be attributed to its anti-microtubular activity. Our previous findings indicated that geiparvarin is able to inhibit the in vitro polymerization of tubulin and to derange the microtubular network in fibroblasts more effectively in the presence of paclitaxel. To further explore its biological activity here we have studied the effects exerted on the other components of the cytoskeleton by geiparvarin and two derivatives obtained by conjugating the 3(2H)-furanone ring of geiparvarin with diethylstilbestrol (DES). Firstly, observations by electron microscopy confirmed anti-microtubular properties, a near-total absence of microtubules is detected when tubulin is incubated with drugs in the presence of paclitaxel, whereas microtubule formation is not inhibited by drugs when assembly is induced by guanosine 5'-triphosphate (GTP). Immunofluorescence assays demonstrated that geiparvarin and DES act in a vinblastine-like fashion, causing a marked depletion of intermediate filaments while the network of microfilaments is not affected. Both the conjugates alter the 'stress fibers' organization of actin and disrupt the vimentin pattern; generally they derange cytoskeleton more markedly than the parent compounds. The cell growth inhibiting effects of geiparvarin and derivatives are dose-dependent; they vary according to the cell line used, when compounds were administered either alone or simultaneously with paclitaxel. Unlike other anti-microtubule agents, they do not exhibit cell-cycle compartment specificity and do not influence thymidine uptake in the cell.
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Affiliation(s)
- C Bocca
- Department of Experimental Medicine and Oncology, University of Torino, Corso Raffaello 30, 10125, Torino, Italy.
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103
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Flynn BL, Flynn GP, Hamel E, Jung MK. The synthesis and tubulin binding activity of thiophene-based analogues of combretastatin A-4. Bioorg Med Chem Lett 2001; 11:2341-3. [PMID: 11527727 DOI: 10.1016/s0960-894x(01)00436-x] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A number of analogues of combretastatin A-4 (1), containing a thiophene ring interposed between the two phenyl groups, have been prepared. The synthesis of these compounds employed a combination of palladium-mediated coupling and iodocyclization techniques. The thiophene compounds 11, 14, 18, and 19 also represent non-benzofused analogues of some recently described tubulin binding benzo[b]thiophenes 3-5. The most active thiophene compounds identified in this study were 11, 14, and 18. Overall they are less active than 1 but exhibit comparable activity to the most active of the benzo[b]thiophenes 3-5. A structure-activity relationship of these compounds is considered.
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Affiliation(s)
- B L Flynn
- Department of Chemistry, The Faculties, Australian National University, Canberra, ACT 0200, Australia.
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104
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Miglietta A, Bocca C, Gabriel L, Rampa A, Bisi A, Valenti P. Antimicrotubular and cytotoxic activity of geiparvarin analogues, alone and in combination with paclitaxel. Cell Biochem Funct 2001; 19:181-9. [PMID: 11494307 DOI: 10.1002/cbf.919] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Geiparvarin is an antiproliferative compound isolated from the leaves of Geijera parviflora, and may represent a new drug which targets tubulin. To better explore the potential use of this agent, we investigated the antimicrotubular and cytotoxic effects of new synthetic aromatic derivatives of geiparvarin. These drugs inhibited polymerization of microtubular protein, particularly when the assembly was induced by paclitaxel. The microtubular network organization of fibroblasts was altered more effectively by some drugs. Normal microtubule architecture completely disappeared when the cells were treated simultaneously with drugs and paclitaxel: microtubules depolymerized or were reorganized into bundles, in a similar but more disarrayed fashion than that observed after treatment with paclitaxel alone. Cytotoxicity studies showed a dose-dependent effect, whereas combined administration of drugs and paclitaxel increased cytotoxicity, more effectively in paclitaxel versus derivatives administration alone.
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Affiliation(s)
- A Miglietta
- Department of Experimental Medicine and Oncology, University of Torino, Corso Raffaello 30, 10125 Torino, Italy.
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105
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Flynn BL, Verdier-Pinard P, Hamel E. A novel palladium-mediated coupling approach to 2,3-disubstituted benzo(b)thiophenes and its application to the synthesis of tubulin binding agents. Org Lett 2001; 3:651-4. [PMID: 11259028 DOI: 10.1021/ol0067179] [Citation(s) in RCA: 182] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[structure: see text]. Flexible, convergent access to 2,3-disubstituted benzo[b]thiophenes has been developed. The most concise approach involves sequential coupling of o-bromoiodobenzenes with benzylmercaptan and zinc acetylides to give benzyl o-ethynylphenyl sulfides which react with iodine to give 3-iodobenzo[b]thiophenes in a 5-endo-dig iodocyclization. These iodides can be further elaborated using palladium-mediated coupling and/or metalation techniques. This method has been applied to the synthesis of some novel tubulin binding agents.
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Affiliation(s)
- B L Flynn
- Department of Chemistry, The Faculties, Australian National University, Canberra, ACT, 0200, Australia.
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106
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Pugh N, Khan IA, Moraes RM, Pasco DS. Podophyllotoxin lignans enhance IL-1beta but suppress TNF-alpha mRNA expression in LPS-treated monocytes. Immunopharmacol Immunotoxicol 2001; 23:83-95. [PMID: 11322652 DOI: 10.1081/iph-100102570] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
There exists a growing body of research which indicates that antimitotics such as taxol and colchicine influence cytokine gene expression. In the present study we examined the effect of podophyllotoxin and six analogs on nuclear factor kappa B (NF-kappa B) activation, and on interleukin-1 beta (IL-1beta) and tumor necrosis factor alpha (TNF-alpha) mRNA expression in human THP-1 monocytes. All compounds were inactive between 0.001microM and 10microM when tested alone. However, podophyllotoxin (0.1 microM) enhanced LPS-induced NF-kappa B activation and IL-1beta mRNA expression between 2 and 3-fold. In contrast, LPS-induced TNF-alpha mRNA expression was decreased between 3 and 6-fold. Comparable results were also observed with the three analogs acetylpodophyllotoxin, 4'-demethylpodophyllotoxin and alpha-peltatin. The remaining three analogs (podophyllotoxin-4-O-glucoside, beta-peltatin-beta-D-glucopyransoide and 1,2,3,4-dehydrodesoxypodophyllotoxin) were inactive. Clearly certain structural features such as the presence of a glycosidic group or ring aromatization results in loss of biological activity. Interestingly, the analogs that were inactive in our assays have also been previously shown to lack affinity for tubulin binding. These results suggest that during the initial hours of exposure to podophyllotoxin or specific analogs these compounds do not act as independent stimulants of human monocyte activation, but can selectively enhance or suppress LPS-induced cytokine gene expression.
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Affiliation(s)
- N Pugh
- Department of Pharmacognosy, Research Institute of Pharmaceutical Sciences, School of Pharmacy, The University of Mississippi, University 38677, USA
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107
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Pettit GR, Lippert JW, Herald DL. A pinacol rearrangement/oxidation synthetic route to hydroxyphenstatin. J Org Chem 2000; 65:7438-44. [PMID: 11076601 DOI: 10.1021/jo000705j] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In an attempt to develop biologically active compounds from the inactive trans isomer (3a) of stilbene 1a, after asymmetric dihydroxylation to optically pure (R,R)-diol 8 the unexpected racemic diphenylacetaldehyde (9) was generated via a Pinacol rearrangement. Several derivatives of diphenylacetaldehyde 9 were synthesized (11-15) and reported. Further reaction of aldehyde 9 during desilylation through autoxidative decarbonylation afforded benzophenone 2b, designated hydroxyphenstatin, a potent antitumor and antimitotic agent. Hydroxyphenstatin showed potent inhibition of the tubulin assembly (IC(50) 0.82 microM) and exhibited an ED(50) of 2.5 microg/mL against the P388 lymphocytic leukemia cell line.
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Affiliation(s)
- G R Pettit
- Cancer Research Institute and Department of Chemistry, Arizona State University, Tempe, Arizona 87287-2404, USA
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108
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109
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Pettit GR, Lippert JW, Herald DL, Hamel E, Pettit RK. Antineoplastic agents 440. Asymmetric synthesis and evaluation of the combretastatin A-1 SAR probes (1S,2S)- and (1R,2R)-1, 2-dihydroxy- 1-(2',3'-dihydroxy-4'-methoxyphenyl)-2-(3' ',4' ',5' '-trimethoxyphenyl)-ethane. JOURNAL OF NATURAL PRODUCTS 2000; 63:969-974. [PMID: 10924176 DOI: 10.1021/np0000623] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The synthetic (E)-isomer (3b) of natural combretastatin A-1 (1a) isolated from the African bushwillow Combretum caffrum was the focus of chiral hydroxylation (Sharpless) reactions as part of a structure-activity relationship study. The resulting (R,R)- and (S,S, )-diols (6 and 7) and synthetic intermediates were evaluated against a series of cancer cell lines, microorganisms, and tubulin. Chiral diols 6 and 7 showed increased activity against the P-388 murine lymphocytic leukemia cell line with ED(50) values of 3.9 and 2.9 microg/mL, respectively, when compared to the precursor (E)-stilbene 3b. In contrast, (E)-stilbene 3b exhibited more potent antibiotic activity than the chiral diols (6 and 7). Both diols, (R,R)-6 and (S, S)-7, displayed less cancer cell growth inhibition and less antibiotic activity than did natural combretastatin A-1 (1a) (P-388 ED(50) 0.25 microg/mL).
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Affiliation(s)
- G R Pettit
- Cancer Research Institute and Department of Chemistry Arizona State University, Tempe, Arizona 85287-2404, USA
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110
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111
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Brecht R, Seitz G, Guénard D, Thoret S. Novel allocolchicinoids with an eight membered B-ring: design, synthesis and inhibition of tubulin assembly. Bioorg Med Chem 2000; 8:557-62. [PMID: 10732972 DOI: 10.1016/s0968-0896(99)00318-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Several B-ring variations of O-methyl androbiphenyline (8), newly accessible from (-)-(M,7S)-colchicine via photooxygenation and subsequent endoperoxide-transformation, were synthesized and evaluated for their inhibitory effects on tubulin assembly in vitro. The amino-allocolchicinoid (9), a key compound in this study, was transformed to the highly potent ketone 10 and by oxidation with H2O2/Na2WO4 to a mixture of syn/anti-oximes, like 11 and 12. These could easily be transformed to hitherto unknown allocolchicinoids 13 and 14 with an eight membered B-ring lactam obtained via a Beckmann rearrangement. Surprisingly both do not notably affect tubulin assembly, despite obvious structural similarities with active analogues of the thiocolchicine- and azasteganacin-series.
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Affiliation(s)
- R Brecht
- Pharmazeutisch-Chemisches Institut der Philipps-Universität, Marburg, Germany
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112
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Polański J. The non-grid technique for modeling 3D QSAR using self-organizing neural network (SOM) and PLS analysis: application to steroids and colchicinoids. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2000; 11:245-261. [PMID: 10969874 DOI: 10.1080/10629360008033234] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A novel method for modeling 3D QSAR has been developed. The method involves a multiple training of a series of self-organizing networks (SOM). The obtained networks have been used for processing the data of one reference molecule. A scheme for the analysis of such data with the PLS analysis has been proposed and tested using the steroids data with corticosteroid binding globulin (CBG) affinity. The predictivity of the CBG models measured with the SDEP parameter is among the best one reported. Although 3-D QSAR models for colchicinoid series is far less predictive, it allows for a discussion on the relative influence of the structural motifs of these compounds.
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Affiliation(s)
- J Polański
- Department of Organic Chemistry, Institute of Chemistry, University of Silesia, Katowice, Poland.
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113
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Schönbrunn E, Phlippen W, Trinczek B, Sack S, Eschenburg S, Mandelkow EM, Mandelkow E. Crystallization of a macromolecular ring assembly of tubulin liganded with the anti-mitotic drug podophyllotoxin. J Struct Biol 1999; 128:211-5. [PMID: 10600574 DOI: 10.1006/jsbi.1999.4183] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The interaction of the anti-cancer drug podophyllotoxin with a high-molecular-weight assembly of tubulin has been employed to produce three-dimensional crystals from avian erythrocyte tubulin as well as from pig brain tubulin. Avian erythrocyte tubulin crystals belong to the space group C2 with unit cell dimensions a = 740 A, b = 330 A, c = 460 A, beta = 128 degrees. The basis of these crystals is ring oligomers with a molecular mass of approximately 6 x 10(6) Da. So far, the crystals diffract to 8-A resolution and a first complete data set to 12-A resolution has been collected under cryogenic conditions. The crystals grew from conventionally purified tubulin consisting of multiple isoforms and different posttranslational modifications. Thus, the use of highly homogeneous tubulin preparations should improve the diffraction quality of these crystals.
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Affiliation(s)
- E Schönbrunn
- Max-Planck-Unit for Structural Molecular Biology, c/o DESY, Hamburg, 22603, Germany.
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114
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Greenwald RB, Conover CD, Pendri A, Choe YH, Martinez A, Wu D, Guan S, Yao Z, Shum KL. Drug delivery of anticancer agents: water soluble 4-poly (ethylene glycol) derivatives of the lignan, podophyllotoxin. J Control Release 1999; 61:281-94. [PMID: 10477801 DOI: 10.1016/s0168-3659(99)00153-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This paper reports on the synthesis and in vivo oncolytic activity of a series of water-soluble acyl derivatives of polyethylene glycol (PEG) conjugated podophyllotoxin. Some analogs of the polymer conjugate showed significantly better activity in a murine leukemia model than native podophyllotoxin suspended in an intralipid emulsion. Additionally, when tested intravenously against a solid lung tumor (A549) model, some conjugated analogs were equivalent to the podophyllotoxin/intralipid emulsion, while those compounds demonstrating slower rates of plasma hydrolysis (in vitro) appeared to cause greater toxicity. There appeared to be an overall correlation between the in vivo antitumor activity of the conjugate and its rate of hydrolysis in vitro, with those showing faster release possessing greater antitumor activity. In conclusion, the solubilization and predictable release of podophyllotoxin from a PEG carrier was achieved and resulted in some derivatives demonstrating, at a minimum, equivalency with podophyllotoxin when administered on an equal molar basis. Further studies may be warranted to assess the PEG-conjugates pharmacokinetics and therapeutic indices in leukemic models.
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Affiliation(s)
- R B Greenwald
- Department of Organic and Medicinal Chemistry, Research and Development, Enzon, Inc., 20 Kingsbridge Road, Piscataway, NJ 08854, USA
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115
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Shan B, Medina JC, Santha E, Frankmoelle WP, Chou TC, Learned RM, Narbut MR, Stott D, Wu P, Jaen JC, Rosen T, Timmermans PB, Beckmann H. Selective, covalent modification of beta-tubulin residue Cys-239 by T138067, an antitumor agent with in vivo efficacy against multidrug-resistant tumors. Proc Natl Acad Sci U S A 1999; 96:5686-91. [PMID: 10318945 PMCID: PMC21921 DOI: 10.1073/pnas.96.10.5686] [Citation(s) in RCA: 128] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Microtubules are linear polymers of alpha- and beta-tubulin heterodimers and are the major constituents of mitotic spindles, which are essential for the separation of chromosomes during mitosis. Here we describe a synthetic compound, 2-fluoro-1-methoxy-4-pentafluorophenylsulfonamidobenzene (T138067), which covalently and selectively modifies the beta1, beta2, and beta4 isotypes of beta-tubulin at a conserved cysteine residue, thereby disrupting microtubule polymerization. Cells exposed to T138067 become altered in shape, indicating a collapse of the cytoskeleton, and show an increase in chromosomal ploidy. Subsequently, these cells undergo apoptosis. Furthermore, T138067 exhibits cytotoxicity against tumor cell lines that exhibit substantial resistance to vinblastine, paclitaxel, doxorubicin, and actinomycin D. T138067 is also equally efficacious in inhibiting the growth of sensitive and multidrug-resistant human tumor xenografts in athymic nude mice. These observations suggest that T138067 may be clinically useful for the treatment of multidrug-resistant tumors.
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Affiliation(s)
- B Shan
- Tularik Inc., Two Corporate Drive, South San Francisco, CA 94080, USA
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116
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Daley L, Guminski Y, Demerseman P, Kruczynski A, Etiévant C, Imbert T, Hill BT, Monneret C. Synthesis and antitumor activity of new glycosides of epipodophyllotoxin, analogues of etoposide, and NK 611. J Med Chem 1998; 41:4475-85. [PMID: 9804687 DOI: 10.1021/jm9800752] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of 3-amino- and 3-alkylamino-2-deoxy-beta-D-ribo- and beta-D-arabino-glycosides of 4'-demethylepipodophyllotoxin have been synthesized by means of an improved trimethylsilyliodide procedure for the podophyllotoxin-4'-demethylepipodophyllotoxin conversion, an efficient and high yielding synthesis of silyl glycoside donors of 3-azido-2,3-dideoxy-beta-D-ribo- and beta-D-arabino-hexopyranosides and stereoselective glycosylations. In vitro evaluation of cytotoxic effects against murine L1210 leukemia critically demonstrates the essential role played by a 4,6-acetal for biological activity. Among the most cytotoxic compounds, 3-amino-2,3-dideoxy- and 3-N, N-(dimethylamino)-2,3-dideoxy etoposide analogues, 17 and 27-29 are at least as potent as etoposide on the in vivo P388 (iv/ip) murine leukemia models. However, surprisingly enough, none of these compounds inhibits the human DNA topoisomerases I or II or binds to tubulin to prevent its polymerization and microtubule assembly. Therefore, their mechanism of action remains to be cleared up.
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Affiliation(s)
- L Daley
- UMR 176 CNRS/Institut Curie, Section Recherche, 26 rue d'Ulm, F-75248 Paris Cedex 05, France
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117
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Li L, Rojiani A, Siemann DW. Targeting the tumor vasculature with combretastatin A-4 disodium phosphate: effects on radiation therapy. Int J Radiat Oncol Biol Phys 1998; 42:899-903. [PMID: 9845118 DOI: 10.1016/s0360-3016(98)00320-4] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
PURPOSE The aim of this study was to evaluate the antitumor efficacy of combretastatin A-4 disodium phosphate (combretastatin prodrug) in the rodent KHT sarcoma model either alone or in combination with radiation therapy. METHODS KHT tumors were grown in C3H/HeJ mice. Combretastatin A-4 prodrug was injected intraperitoneally at doses ranging from 10 to 100 mg/kg. Tumors were irradiated in unanesthetized mice using a 137Cs source. Tumor response to combretastatin A-4 prodrug was assessed by histological evaluations as well as an in vivo to in vitro cell survival assay. RESULTS Histological evaluation showed morphological damage of tumor cells within a few hours after drug treatment, followed by extensive central necrosis. Administering increasing doses of combretastatin A-4 prodrug to tumor-bearing mice resulted in a dose-dependent increase in cell killing irrespective of whether the tumors were irradiated or not. When combined with radiation, a 100 mg/kg dose of combretastatin A-4 prodrug reduced tumor cell survival 10-500-fold lower than that seen with radiation alone. Further, the shape of the cell survival curve observed following the combination therapy suggested that including combretastatin in the treatment had a major effect on the radiation-resistant hypoxic cell subpopulation associated with this tumor. CONCLUSION The present results demonstrated that in the KHT sarcoma, combretastatin A-4 prodrug caused rapid vascular shutdown, a concentration-dependent direct cell killing, and effective enhancement of the antitumor effects of radiation therapy.
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Affiliation(s)
- L Li
- Department of Pharmacology and Experimental Therapeutics, University of Florida, Gainesville 32610, USA
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118
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119
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Jordan A, Hadfield JA, Lawrence NJ, McGown AT. Tubulin as a target for anticancer drugs: agents which interact with the mitotic spindle. Med Res Rev 1998; 18:259-96. [PMID: 9664292 DOI: 10.1002/(sici)1098-1128(199807)18:4<259::aid-med3>3.0.co;2-u] [Citation(s) in RCA: 496] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Tubulin is the biochemical target for several clinically used anticancer drugs, including paclitaxel and the vinca alkaloids vincristine and vinblastine. This review describes both the natural and synthetic agents which are known to interact with tubulin. Syntheses of the more complex agents are referenced and the potential clinical use of the compounds is discussed. This review describes the biochemistry of tubulin, microtubules, and the mitotic spindle. The agents are discussed in relation to the type of binding site on the protein with which they interact. These are the colchicine, vinca alkaloid, rhizoxin/maytansine, and tubulin sulfhydryl binding sites. Also included are the agents which either bind at other sites or unknown sites on tubulin. The literature is reviewed up to October 1997.
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Affiliation(s)
- A Jordan
- Department of Chemistry, University of Manchester Institute of Science and Technology, UK
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120
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Synthesis of (±)-7-(3,4,5-trimethoxyphenyl)-7-deoxyidarubicinone. A new family of anthracycline analogues. Tetrahedron 1998. [DOI: 10.1016/s0040-4020(98)00304-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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121
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Abstract
This review deals with the historical discovery of particularly important lignan derivatives used in cancer chemotherapy. From isolation of the naturally occurring podophyllotoxin, an inhibitor of microtubule assembly, to hemisynthesis of the clinically important anticancer drugs etoposide and teniposide, it will be demonstrated how the activities and the ability of this class of compounds to inhibit topoisomerase II were discovered by different research teams. By virtue of these discoveries, new hemisynthetic derivatives, with different mechanisms of action, are bringing improvements in the ability to treat cancer.
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Affiliation(s)
- T F Imbert
- Division of Medicinal Chemistry, Centre de Recherche Pierre Fabre, Castres, France
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122
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Acosta J, Caballero E, Grávalos D, Medarde M, Sahagún H, Stoodley R, Tomé F. New 7-aryl analogues of anthracyclines: Synthesis and cytotoxic activity of (±)-7-(3,4,5-trimethoxyphenyl)-7-deoxyidarubicinone. Bioorg Med Chem Lett 1997. [DOI: 10.1016/s0960-894x(97)10122-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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123
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Brecht R, Haenel F, Seitz G. Dihydrocolchicine 8,12-Endoperoxide: A Novel Starting Material for Convenient Syntheses of the AllocolchicinoidsN-AcetylcolchinolO-Methyl Ether and Androbiphenyline. ACTA ACUST UNITED AC 1997. [DOI: 10.1002/jlac.199719971115] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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124
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Fürstner A, Nikolakis K. Ethynylation of Aryl Halides by a Modified Suzuki Reaction: Application to the Syntheses of Combretastatin A-4, A-5 and Lunularic Acid. ACTA ACUST UNITED AC 1996. [DOI: 10.1002/jlac.199619961224] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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125
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ter Haar E, Rosenkranz HS, Hamel E, Day BW. Computational and molecular modeling evaluation of the structural basis for tubulin polymerization inhibition by colchicine site agents. Bioorg Med Chem 1996; 4:1659-71. [PMID: 8931935 DOI: 10.1016/0968-0896(96)00158-7] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The computer-automated structure evaluation programs MultiCASE and CASE were used to perform a quantitative structure-activity relationship study on tubulin polymerization inhibitors. A learning set of 536 chemicals (202 active. 27 marginal, and 307 inactive), built using IC50 values for inhibition of tubulin polymerization or mitosis from this and previous studies, was used for artificial intelligence self-teaching. The algorithms successfully predicted the activity of agents in the learning set with > 90% accuracy. Seventeen MultiCASE and twelve CASE (mostly included in the MultiCASE set) biophores (substructures significantly correlated with activity) were identified with a probability > 0.95. Here we present the biophores of podophyllotoxins, colchicinoids, and certain combretastatins, each examined for structure-activity relationships. For the podophyllotoxins and colchicinoids in the learning set, the correlations between observed and predicted potencies were > 0.85. The algorithms recognized the importance of several known site, electronic, and steric effects in the two classes. A predictive QSAR (R2 = 0.98) was developed for combretastain A-2 and dihydrocombretastatin analogues. The MultiCASE/CASE analyzes were used in combination with molecular models to study relative orientations of colchicine, podophyllotoxin, combretastatin A-4, and steganacin at the colchicine site. This resulted in a new hypothesis, consistent with extensive published experimental data, in which the C-ring and part of the B-ring of colchicine overlap with the A- and B-rings of podophyllotoxin. Consequently, the trimethoxyphenyl rings of colchicine and podophyllotoxin occupied different regions of space, each pointing out from a hydrophobic 'core' occupied by the overlapping biophores. The molecular model of the highly potent combretastatin A-4 could fit into the model binding site in at least three different ways. The developed QSARs were used to identify the potent microtubule stabilizer discodermolide. Its identification, in concert with recently reported findings, suggest potential overlap in the colchicine and paclitaxel binding sites on tubulin.
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Affiliation(s)
- E ter Haar
- Department of Environmental and Occupational Health, University of Pittsburgh Cancer Institute, University of Pittsburgh, PA 15238, USA
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Mooberry SL, Taoka CR, Busquets L. Cryptophycin 1 binds to tubulin at a site distinct from the colchicine binding site and at a site that may overlap the vinca binding site. Cancer Lett 1996; 107:53-7. [PMID: 8913266 DOI: 10.1016/0304-3835(96)04342-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Cryptophycin 1 is a new cytotoxic antimicrotubule agent with excellent antitumor activity. The methods of Sackett (Biochemistry, 34, 7010-7019, 1995), utilizing the selective and specific proteolysis of alpha- and beta-tubulin by trypsin and chymotrypsin, was used to identify the cryptophycin 1 binding site on tubulin. Occupancy of the colchicine or vinca binding sites causes changes in the structure of tubulin that can be detected by proteolysis with trypsin and chymotrypsin. The addition of cryptophycin 1 to tubulin causes changes in both the tryptic and chymotryptic cleavage of tubulin consistent with occupation of the vinca binding site and distinct from occupation of the colchicine binding site. The effects of cryptophycin 1 on the tryptic digests are identical to the effects seen with vinblastine and differ saliently from the effects of maytansine and rhizoxin, other agents known to bind to the vinca site. The data suggest that the binding site of cryptophycin 1 may overlap the vinca binding site on tubulin.
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Affiliation(s)
- S L Mooberry
- Cancer Research Center of Hawaii, University of Hawaii at Manoa, Honolulu 96813, USA
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128
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Cho SJ, Kashiwada Y, Bastow KF, Cheng YC, Lee KH. Antitumor agents. 164. Podophenazine, 2'',3''-dichloropodophenazine, benzopodophenazine, and their 4 beta-p-nitroaniline derivatives as novel DNA topoisomerase II inhibitors. J Med Chem 1996; 39:1396-402. [PMID: 8691469 DOI: 10.1021/jm950548u] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We report here the synthesis and biological evaluation of novel DNA topoisomerase II inhibitors, podophenazine (8), 2'',3'' "-dichloropodophenazine (9), and benzopodophenazine (10), and their 4beta-p-nitroaniline derivatives 13-15. Among these, 4'-0-demethyl-4beta-(4'''- nitroanilino)-4-desoxypodophenazine (13) and 4'-O-demethyl-2'',3''-dichloro-4beta-(4-'''-nitroanilino)-4- desoxypodophenazine (14) were found to inhibit KB cells at sub-micromolar concentrations (IC50 = 0.11 +/- 0.03 and 0.48 +/- 0.17 microM, respectively. Against KB/7d cells (a pleiotrophic multiple drug-resistant subclone selected with etoposide which has reduced level of topoisomerase II), only compound 13 out of a target series maintained activity in the sub-micromolar concentration range with a IC 50 value of 0.56 +/- 0.13 mu M. The differential toxicity ratio for 13 [IC 50 (KB/7d)/IC 50 (KB)] was approximately 5. Unlike etoposide and its congeners, compounds 13 and 14 were found to be weak inhibitors of the catalytic activity of topoisomerase II (IC100 = > 100 and > 150 microM, respectively). In vitro protein-linked DNA complex formation assay revealed that 13 and 14, respectively, induced marginal response (13 at 1 microM, 320.3 +/- 124.5 cpm; 13 at 50 microM, 308.8 +/- 139.9 cpm; 13 at 100 mu M, 446.0 +/- 153.5 cpm) and no response (14 at 1 microM, 104.9 +/- 52.6 cpm; 14 at 50 microM, 103.3 +/- 42.6 cpm; 14 at 100 microM, 101.4 +/- 35.2 cpm) compared to the enzyme control. On the basis of these results, we conclude that the mechanism of enzyme inhibition of these compounds is distinct from that of etoposide and its congeners. We are currently investigating the mechanism(s) of action of compounds 13 and 14 as well as synthesizing other derivatives in order to better characterize structure-activity relationships of this series of compounds.
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Affiliation(s)
- S J Cho
- Division of Medicinal Chemistry and Natural Products, School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599, USA
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Cho SJ, Tropsha A, Suffness M, Cheng YC, Lee KH. Antitumor agents. 163. Three-dimensional quantitative structure-activity relationship study of 4'-O-demethylepipodophyllotoxin analogs using the modified CoMFA/q2-GRS approach. J Med Chem 1996; 39:1383-95. [PMID: 8691468 DOI: 10.1021/jm9503052] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Analogs of 4'O-demethylepipodophyllotoxin are considered as potential anticancer agents. We have applied comparative molecular field analysis (CoMFA) and a novel CoMFA/q2-GRS technique recently developed in our group to identify the essential structural requirements for increasing the ability of these compounds to form cellular protein-DNA complex. In addition, a new method to incorporate different types of probe atoms as part of q2-GRS routine has been developed. The best final model with 101 compounds using a combination of four different sets of probe atoms and charges [C (sp3, +1), C (sp3, 0), H (+1), and O (sp3, -1)] yielded a q 2 of 0.584 and the standard error of prediction of 0.660 at 5 principal components. The steric and electrostatic contour plots of the final model were compared with the DNA phosphate backbone environment of the DNA-4'O-demethylepipodophylltoxin analog complex, which was generated using the X-ray structure of the DNA-nogalamycin complex. The comparison reveals that the CoMFA steric and electrostatic fields are compatible with stereochemical properties of the DNA backbone. The results obtained from this study shall guide our future synthetic efforts.
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Affiliation(s)
- S J Cho
- Division of Medicinal Chemistry and Natural Products, School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina, 27599, USA
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Abstract
Microtubule research is becoming increasingly diverse, reflecting the many isoforms and modifications of tubulin and the many proteins with which microtubules interact. Recent advances are particularly visible in four areas: microtubule motor proteins (their structures, stepping modes, and forces); microtubule nucleation (the roles of centrosomes and gamma-tubulin); tubulin folding (mediated by cytoplasmic chaperones); and the expanding list of microtubule-associated proteins, knowledge of their phosphorylation states, and information on their effects on microtubule dynamics.
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Affiliation(s)
- E Mandelkow
- Max Planck Unit for Structural Molecular Biology, Hamburg, Germany
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Sackett DL. Structure and function in the tubulin dimer and the role of the acidic carboxyl terminus. Subcell Biochem 1995; 24:255-302. [PMID: 7900178 DOI: 10.1007/978-1-4899-1727-0_9] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- D L Sackett
- Laboratory of Biochemical Pharmacology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
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