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Wong DYQ, Ong WWF, Ang WH. Induction of Immunogenic Cell Death by Chemotherapeutic Platinum Complexes. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201500934] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Wong DYQ, Ong WWF, Ang WH. Induction of immunogenic cell death by chemotherapeutic platinum complexes. Angew Chem Int Ed Engl 2015; 54:6483-7. [PMID: 25873535 DOI: 10.1002/anie.201500934] [Citation(s) in RCA: 116] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2015] [Indexed: 12/22/2022]
Abstract
There is compelling evidence suggesting that the immune-modulating effects of many conventional chemotherapeutics, including platinum-based agents, play a crucial role in achieving clinical response. One way in which chemotherapeutics can engage a tumor-specific immune response is by triggering an immunogenic mode of tumor cell death (ICD), which then acts as an "anticancer vaccine". In spite of being a mainstay of chemotherapy, there has not been a systematic attempt to screen both existing and upcoming Pt agents for their ICD ability. A library of chemotherapeutically active Pt agents was evaluated in an in vitro phagocytosis assay, and no correlation between cytotoxicity and phagocytosis was observed. A Pt(II) N-heterocyclic carbene complex was found to display the characteristic hallmarks of a type II ICD inducer, namely focused oxidative endoplasmic reticulum (ER) stress, calreticulin exposure, and both HMGB1 and ATP release, and thus identified as the first small-molecule immuno-chemotherapeutic agent.
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Ong JX, Yap SQ, Wong DYQ, Chin CF, Ang WH. Platinum(IV) Carboxylate Prodrug Complexes as Versatile Platforms for Targeted Chemotherapy. Chimia (Aarau) 2015; 69:100-3. [DOI: 10.2533/chimia.2015.100] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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54
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Wong DYQ, Lim JH, Ang WH. Induction of targeted necrosis with HER2-targeted platinum(iv) anticancer prodrugs. Chem Sci 2015; 6:3051-3056. [PMID: 28706680 PMCID: PMC5490001 DOI: 10.1039/c5sc00015g] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2015] [Accepted: 03/16/2015] [Indexed: 01/07/2023] Open
Abstract
It is well-recognized that the failure of many chemotherapeutics arises due to an inability to induce apoptosis. Most cancers acquire a myriad of pro-survival adaptations, and the vast heterogeneity and accumulation of multiple often unrelated anti-apoptotic signaling pathways have been a major stumbling block towards the development of conventional chemotherapeutics, which can overcome drug resistance. We have developed highly potent and selective HER2-targeted Pt(iv) prodrugs bearing anti-HER2/neu peptides that induce targeted necrosis as a novel strategy to circumvent apoptosis-resistance. These Pt(iv)-peptide conjugates exhibit a unique biphasic mode of cytotoxicity comprising rapid killing of cancer cells via necrosis in the first phase followed by an extended and gradual phase of delayed cell death. We demonstrate that these Pt(iv)-peptide prodrugs are more potent than their Pt(ii) congeners in direct cell-killing and exhibit comparable long-term inhibition of proliferative capacity and with greater selectivity against HER2-positive cancer cells.
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55
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Muzi L, Ménard-Moyon C, Russier J, Li J, Chin CF, Ang WH, Pastorin G, Risuleo G, Bianco A. Diameter-dependent release of a cisplatin pro-drug from small and large functionalized carbon nanotubes. NANOSCALE 2015; 7:5383-94. [PMID: 25727105 DOI: 10.1039/c5nr00220f] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The use of platinum-based chemotherapeutic drugs in cancer therapy still suffers from severe disadvantages, such as lack of appropriate selectivity for tumor tissues and insurgence of multi-drug resistance. Moreover, drug efficacy can be attenuated by several mechanisms such as premature drug inactivation, reduced drug uptake inside cells and increased drug efflux once internalized. The use of functionalized carbon nanotubes (CNTs) as chemotherapeutic drug delivery systems is a promising strategy to overcome such limitations due to their ability to enhance cellular internalization of poorly permeable drugs and thus increase the drug bioavailability at the diseased site, compared to the free drug. Furthermore, the possibility to encapsulate agents in the nanotubes' inner cavity can protect the drug from early inactivation and their external functionalizable surface is useful for selective targeting. In this study, a hydrophobic platinum(IV) complex was encapsulated within the inner space of two different diameter functionalized multi-walled CNTs (Pt(IV)@CNTs). The behavior of the complexes, compared to the free drug, was investigated on both HeLa human cancer cells and RAW 264.7 murine macrophages. Both CNT samples efficiently induced cell death in HeLa cancer cells 72 hours after the end of exposure to CNTs. Although the larger diameter CNTs were more cytotoxic on HeLa cells compared to both the free drug and the smaller diameter nanotubes, the latter allowed a prolonged release of the encapsulated drug, thus increasing its anticancer efficacy. In contrast, both Pt(IV)@CNT constructs were poorly cytotoxic on macrophages and induced negligible cell activation and no pro-inflammatory cytokine production. Both CNT samples were efficiently internalized by the two types of cells, as demonstrated by transmission electron microscopy observations and flow cytometry analysis. Finally, the platinum levels found in the cells after Pt(IV)@CNT exposure demonstrate that they can promote drug accumulation inside cells in comparison with treatment with the free complex. To conclude, our study shows that CNTs are promising nanocarriers to improve the accumulation of a chemotherapeutic drug and its slow release inside tumor cells, by tuning the CNT diameter, without inducing a high inflammatory response.
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Chow MJ, Licona C, Yuan Qiang Wong D, Pastorin G, Gaiddon C, Ang WH. Discovery and investigation of anticancer ruthenium-arene Schiff-base complexes via water-promoted combinatorial three-component assembly. J Med Chem 2014; 57:6043-59. [PMID: 25023617 DOI: 10.1021/jm500455p] [Citation(s) in RCA: 109] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The structural diversity of metal scaffolds makes them a viable alternative to traditional organic scaffolds for drug design. Combinatorial chemistry and multicomponent reactions, coupled with high-throughput screening, are useful techniques in drug discovery, but they are rarely used in metal-based drug design. We report the optimization and validation of a new combinatorial, metal-based, three-component assembly reaction for the synthesis of a library of 442 Ru-arene Schiff-base (RAS) complexes. These RAS complexes were synthesized in a one-pot, on-a-plate format using commercially available starting materials under aqueous conditions. The library was screened for their anticancer activity, and several cytotoxic lead compounds were identified. In particular, [(η6-1,3,5-triisopropylbenzene)RuCl(4-methoxy-N-(2-quinolinylmethylene)aniline)]Cl (4) displayed low micromolar IC50 values in ovarian cancers (A2780, A2780cisR), breast cancer (MCF7), and colorectal cancer (HCT116, SW480). The absence of p53 activation or changes in IC50 value between p53+/+ and p53-/- cells suggests that 4 and possibly the other lead compounds may act independently of the p53 tumor suppressor gene frequently mutated in cancer.
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Wong DYQ, Yeo CHF, Ang WH. Immuno-chemotherapeutic platinum(IV) prodrugs of cisplatin as multimodal anticancer agents. Angew Chem Int Ed Engl 2014; 53:6752-6. [PMID: 24844571 DOI: 10.1002/anie.201402879] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Indexed: 12/22/2022]
Abstract
There is growing consensus that the clinical therapeutic efficacy of some chemotherapeutic agents depends on their off-target immune-modulating effects. Pt anticancer drugs have previously been identified to be potent immunomodulators of both the innate and the adaptive immune system. Nevertheless, there has been little development in the rational design of Pt-based chemotherapeutic agents to exploit their immune-activating capabilities. The FPR1/2 formyl peptide receptors are highly expressed in immune cells, as well as in many metastatic cancers. Herein, we report a rationally designed multimodal Pt(IV) prodrug containing a FPR1/2-targeting peptide that combines chemotherapy with immunotherapy to achieve therapeutic synergy and demonstrate the feasibility of this approach.
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Wong DYQ, Yeo CHF, Ang WH. Immuno-Chemotherapeutic Platinum(IV) Prodrugs of Cisplatin as Multimodal Anticancer Agents. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201402879] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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59
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Adhireksan Z, Davey GE, Campomanes P, Groessl M, Clavel CM, Yu H, Nazarov AA, Yeo CHF, Ang WH, Dröge P, Rothlisberger U, Dyson PJ, Davey CA. Ligand substitutions between ruthenium-cymene compounds can control protein versus DNA targeting and anticancer activity. Nat Commun 2014; 5:3462. [PMID: 24637564 PMCID: PMC3959212 DOI: 10.1038/ncomms4462] [Citation(s) in RCA: 237] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 02/18/2014] [Indexed: 01/06/2023] Open
Abstract
Ruthenium compounds have become promising alternatives to platinum drugs by displaying specific activities against different cancers and favourable toxicity and clearance properties. Nonetheless, their molecular targeting and mechanism of action are poorly understood. Here we study two prototypical ruthenium-arene agents-the cytotoxic antiprimary tumour compound [(η(6)-p-cymene)Ru(ethylene-diamine)Cl]PF6 and the relatively non-cytotoxic antimetastasis compound [(η(6)-p-cymene)Ru(1,3,5-triaza-7-phosphaadamantane)Cl2]-and discover that the former targets the DNA of chromatin, while the latter preferentially forms adducts on the histone proteins. Using a novel 'atom-to-cell' approach, we establish the basis for the surprisingly site-selective adduct formation behaviour and distinct cellular impact of these two chemically similar anticancer agents, which suggests that the cytotoxic effects arise largely from DNA lesions, whereas the protein adducts may be linked to the other therapeutic activities. Our study shows promise for developing new ruthenium drugs, via ligand-based modulation of DNA versus protein binding and thus cytotoxic potential, to target distinguishing epigenetic features of cancer cells.
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Li J, Pant A, Chin CF, Ang WH, Ménard-Moyon C, Nayak TR, Gibson D, Ramaprabhu S, Panczyk T, Bianco A, Pastorin G. In vivo biodistribution of platinum-based drugs encapsulated into multi-walled carbon nanotubes. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2014; 10:1465-75. [PMID: 24486857 DOI: 10.1016/j.nano.2014.01.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Revised: 01/08/2014] [Accepted: 01/17/2014] [Indexed: 02/04/2023]
Abstract
Carbon nanotubes (CNTs) are promising drug delivery systems due to their external functionalizable surface and their hollowed cavity that can encapsulate several bioactive molecules. In this study, the chemotherapeutic drug cisplatin or an inert platinum(IV) complex were entrapped inside functionalized-multi-walled-CNTs and intravenously injected into mice to investigate the influence of CNTs on the biodistribution of Pt-based molecules. The platinum levels in vital organs suggested that functionalized-CNTs did not affect cisplatin distribution, while they significantly enhanced the accumulation of Pt(IV) sample in some tissues (e.g. in the lungs, suggesting their potential application in lung cancer therapy) and reduced both kidney and liver accumulation (thus decreasing eventual nephrotoxicity, a typical side effect of cisplatin). Concurrently, CNTs did not induce any intrinsic abnormal immune response or inflammation, as confirmed by normal cytokine levels and histological evaluations. Therefore, functionalized nanotubes represent an efficient nano-carrier to improve accumulation of Pt species in targeted tissues/organs. From the clinical editor: In this preclinical study functionalized carbon nanotubes are reported to be safe and efficient for targeted delivery of platinum-containing compounds in rodents. Approaches like this may improve the treatment of specific cancers, since platinum based chemotherapies are commonly used, yet limited by toxicity and relatively poor target tissue concentration.
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Fei Z, Păunescu E, Ang WH, Scopelliti R, Dyson PJ. Phosphorylation of Diaminopyridines: Synthesis of a Compound Containing Both a Diphosphinoamine (P–N–P) and an Iminobiphosphine (N=P–P) Fragment. Eur J Inorg Chem 2014. [DOI: 10.1002/ejic.201301143] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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62
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Chin CF, Yap SQ, Li J, Pastorin G, Ang WH. Ratiometric delivery of cisplatin and doxorubicin using tumour-targeting carbon-nanotubes entrapping platinum(iv) prodrugs. Chem Sci 2014. [DOI: 10.1039/c3sc53106f] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A hydrophobic platinum(iv) prodrug was entrapped in tumour-targeting multiwalled carbon nanotubes for synchronous and ratiometric delivery of drug combinations.
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63
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Wong BS, Yoong SL, Jagusiak A, Panczyk T, Ho HK, Ang WH, Pastorin G. Carbon nanotubes for delivery of small molecule drugs. Adv Drug Deliv Rev 2013; 65:1964-2015. [PMID: 23954402 DOI: 10.1016/j.addr.2013.08.005] [Citation(s) in RCA: 326] [Impact Index Per Article: 29.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 08/01/2013] [Accepted: 08/05/2013] [Indexed: 11/30/2022]
Abstract
In the realm of drug delivery, carbon nanotubes (CNTs) have gained tremendous attention as promising nanocarriers, owing to their distinct characteristics, such as high surface area, enhanced cellular uptake and the possibility to be easily conjugated with many therapeutics, including both small molecules and biologics, displaying superior efficacy, enhanced specificity and diminished side effects. While most CNT-based drug delivery system (DDS) had been engineered to combat cancers, there are also emerging reports that employ CNTs as either the main carrier or adjunct material for the delivery of various non-anticancer drugs. In this review, the delivery of small molecule drugs is expounded, with special attention paid to the current progress of in vitro and in vivo research involving CNT-based DDSs, before finally concluding with some consideration on inevitable complications that hamper successful disease intervention with CNTs.
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Yoong SL, Wong BS, Zhou QL, Chin CF, Li J, Venkatesan T, Ho HK, Yu V, Ang WH, Pastorin G. Enhanced cytotoxicity to cancer cells by mitochondria-targeting MWCNTs containing platinum(IV) prodrug of cisplatin. Biomaterials 2013; 35:748-59. [PMID: 24140044 DOI: 10.1016/j.biomaterials.2013.09.036] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Accepted: 09/11/2013] [Indexed: 12/11/2022]
Abstract
Among the arsenal of nano-materials, carbon nanotubes (CNTs) are becoming more prominent due to favorable attributes including their unique shape, which promotes cellular-uptake, and large aspect-ratio that facilitates functionalization of bioactive molecules on their surface. In this study, multi-walled carbon nanotubes (MWCNTs) were functionalized with either mitochondrial-targeting fluorescent rhodamine-110 (MWCNT-Rho) or non-targeting fluorescein (MWCNT-Fluo). Despite structural similarities, MWCNT-Rho associated well with mitochondria (ca. 80% co-localization) in contrast to MWCNT-Fluo, which was poorly localized (ca. 21% co-localization). Additionally, MWCNT-Rho entrapping platinum(IV) pro-drug of cisplatin (PtBz) displayed enhanced potency (IC50 = 0.34 ± 0.07 μM) compared to a construct based on MWCNT-Fluo (IC50 ≥ 2.64 μM). Concurrently, preliminary in vitro toxicity evaluation revealed that empty MWCNT-Rho neither decreased cell viability significantly nor interfered with mitochondrial membrane-potential, while seemingly being partially expelled from cells. Due to its targeting capability and apparent lack of cytotoxicity, MWCNT-Rho complex was used to co-encapsulate PtBz and a chemo-potentiator, 3-bromopyruvate (BP), and the resulting MWCNT-Rho(PtBz+BP) construct demonstrated superior efficacy over PtBz free drug in several cancer cell lines tested. Importantly, a 2-fold decrease in mitochondrial potential was observed, implying that mitochondrial targeting of compounds indeed incurred additional intended damage to mitochondria.
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Montagner D, Yap SQ, Ang WH. A Fluorescent Probe for Investigating the Activation of Anticancer Platinum(IV) Prodrugs Based on the Cisplatin Scaffold. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201305734] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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66
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Montagner D, Yap SQ, Ang WH. A fluorescent probe for investigating the activation of anticancer platinum(IV) prodrugs based on the cisplatin scaffold. Angew Chem Int Ed Engl 2013; 52:11785-9. [PMID: 24105908 DOI: 10.1002/anie.201305734] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Indexed: 01/28/2023]
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67
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Paira P, Chow MJ, Venkatesan G, Kosaraju VK, Cheong SL, Klotz KN, Ang WH, Pastorin G. Organoruthenium Antagonists of Human A3Adenosine Receptors. Chemistry 2013; 19:8321-30. [DOI: 10.1002/chem.201203291] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Revised: 01/15/2013] [Indexed: 11/09/2022]
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68
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Ong JX, Yap CW, Ang WH. Rational Design of Selective Organoruthenium Inhibitors of Protein Tyrosine Phosphatase 1B. Inorg Chem 2012; 51:12483-92. [DOI: 10.1021/ic301884j] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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69
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Chin CF, Tian Q, Setyawati MI, Fang W, Tan ESQ, Leong DT, Ang WH. Tuning the Activity of Platinum(IV) Anticancer Complexes through Asymmetric Acylation. J Med Chem 2012; 55:7571-82. [DOI: 10.1021/jm300580y] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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70
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Tian Q, Wong W, Xu Y, Chan Y, Ho HK, Pastorin G, Ang WH. Immobilisation of quantum dots by bio-orthogonal PCR amplification and labelling for direct gene detection and quantitation. Chem Commun (Camb) 2012; 48:5467-9. [PMID: 22540122 DOI: 10.1039/c2cc30680h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A sensitive and versatile detection scheme based on quantum dot immobilisation on a solid support through bio-orthogonal PCR amplification and labelling has been developed for detection and quantification of gene targets in complex DNA mixtures.
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71
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Nazarov AA, Risse J, Ang WH, Schmitt F, Zava O, Ruggi A, Groessl M, Scopelitti R, Juillerat-Jeanneret L, Hartinger CG, Dyson PJ. Anthracene-Tethered Ruthenium(II) Arene Complexes as Tools To Visualize the Cellular Localization of Putative Organometallic Anticancer Compounds. Inorg Chem 2012; 51:3633-9. [DOI: 10.1021/ic202530j] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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72
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Chin CF, Wong DYQ, Jothibasu R, Ang WH. Anticancer platinum (IV) prodrugs with novel modes of activity. Curr Top Med Chem 2012; 11:2602-12. [PMID: 22039869 DOI: 10.2174/156802611798040778] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2010] [Accepted: 05/31/2010] [Indexed: 11/22/2022]
Abstract
Over the past four decades, the search for improved platinum drugs based on the classical platinum (II)-diam(m)ine pharmacophore has yielded only a handful of successful candidates. New methodologies centred on platinum (IV) complexes, with better stability and expanded coordination spheres, offer the possibility of overcoming limitations inherent to platinum (II) drugs. In this review, novel strategies of targeting and killing cancer cells using platinum (IV) constructs are discussed. These approaches exploit the unique electrochemical characteristics and structural attributes of platinum (IV) complexes as a means of developing anticancer prodrugs that can target and selectively destroy cancer cells. Anticancer platinum (IV) prodrugs represent promising new strategies as targeted chemotherapeutic agents in the ongoing battle against cancer.
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73
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Astarina A, Chow MJ, Ang WH. Transcription Inhibition by Organometallic Ruthenium - Arene Anticancer Complexes in Live Mammalian Cells. Aust J Chem 2012. [DOI: 10.1071/ch12059] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Organometallic ruthenium–arene RAPTA complexes, currently being actively pursued as potential anticancer agents, interact with intracellular biological targets to form covalent adducts. Because their mode of action is still unclear, we investigated their binding with DNA and the ability of ruthenated-DNA adducts to elicit cellular responses such as transcription inhibition and repair. To investigate the influence of the spectator arene ligands on RAPTA activity, a novel RAPTA complex containing the bulky 1,3,5-triisopropylbenzene ligand was synthesized and characterized. Transcription experiments carried out in live mammalian cells using ruthenated plasmid probes revealed that increasing steric bulk of the arene ligand did not improve its ability to arrest transcription.
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Wong DYQ, Lau JY, Ang WH. Harnessing chemoselective imine ligation for tethering bioactive molecules to platinum(iv) prodrugs. Dalton Trans 2012; 41:6104-11. [DOI: 10.1039/c2dt30264k] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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75
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Li J, Yap SQ, Chin CF, Tian Q, Yoong SL, Pastorin G, Ang WH. Platinum(iv) prodrugs entrapped within multiwalled carbon nanotubes: Selective release by chemical reduction and hydrophobicity reversal. Chem Sci 2012. [DOI: 10.1039/c2sc01086k] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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