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Destroying the Shield of Cancer Stem Cells: Natural Compounds as Promising Players in Cancer Therapy. J Clin Med 2022; 11:jcm11236996. [PMID: 36498571 PMCID: PMC9737492 DOI: 10.3390/jcm11236996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 11/21/2022] [Accepted: 11/24/2022] [Indexed: 11/29/2022] Open
Abstract
In a scenario where eco-sustainability and a reduction in chemotherapeutic drug waste are certainly a prerogative to safeguard the biosphere, the use of natural products (NPs) represents an alternative therapeutic approach to counteract cancer diseases. The presence of a heterogeneous cancer stem cell (CSC) population within a tumor bulk is related to disease recurrence and therapy resistance. For this reason, CSC targeting presents a promising strategy for hampering cancer recurrence. Increasing evidence shows that NPs can inhibit crucial signaling pathways involved in the maintenance of CSC stemness and sensitize CSCs to standard chemotherapeutic treatments. Moreover, their limited toxicity and low costs for large-scale production could accelerate the use of NPs in clinical settings. In this review, we will summarize the most relevant studies regarding the effects of NPs derived from major natural sources, e.g., food, botanical, and marine species, on CSCs, elucidating their use in pre-clinical and clinical studies.
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Bio-Inspired Smart Nanoparticles in Enhanced Cancer Theranostics and Targeted Drug Delivery. J Funct Biomater 2022; 13:jfb13040207. [PMID: 36412848 PMCID: PMC9680339 DOI: 10.3390/jfb13040207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 10/23/2022] [Accepted: 10/24/2022] [Indexed: 12/14/2022] Open
Abstract
Globally, a significant portion of deaths are caused by cancer.Compared with traditional treatment, nanotechnology offers new therapeutic options for cancer due to its ability to selectively target and control drug release. Among the various routes of nanoparticle synthesis, plants have gained significant recognition. The tremendous potential of medicinal plants in anticancer treatments calls for a comprehensive review of existing studies on plant-based nanoparticles. The study examined various metallic nanoparticles obtained by green synthesis using medicinal plants. Plants contain biomolecules, secondary metabolites, and coenzymes that facilitate the reduction of metal ions into nanoparticles. These nanoparticles are believed to be potential antioxidants and cancer-fighting agents. This review aims at the futuristic intuitions of biosynthesis and applications of plant-based nanoparticles in cancer theranostics.
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Pósa SP, Dargó G, Nagy S, Kisszékelyi P, Garádi Z, Hámori L, Szakács G, Kupai J, Tóth S. Cytotoxicity of cinchona alkaloid organocatalysts against MES-SA and MES-SA/Dx5 multidrug-resistant uterine sarcoma cell lines. Bioorg Med Chem 2022; 67:116855. [PMID: 35640378 DOI: 10.1016/j.bmc.2022.116855] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 05/10/2022] [Accepted: 05/23/2022] [Indexed: 11/18/2022]
Abstract
Since the first application of natural quinine as an anti-malarial drug, cinchona alkaloids and their derivatives have been exhaustively studied for their biological activity. In our work, we tested 13 cinchona alkaloid organocatalysts, synthesised from quinine. These derivatives were screened against MES-SA and Dx5 uterine sarcoma cell lines for in vitro anticancer activity and to investigate their potential to overcome P-glycoprotein (P-gp) mediated multidrug resistance (MDR). Decorating quinine with hydrogen-bond donor units, such as thiourea and (thio)squaramide, resulted in decreased half-maximal growth inhibition values on both cell lines (1.3-21 µM) compared to quinine and other cinchona alcohols (47-111 µM). Further cytotoxicity studies conducted in the presence of the P-gp inhibitor tariquidar indicated that several analogues, especially cinchona amines and squaramides, but not thiosquaramide, were expelled from MDR cells by P-gp. Similarly to the established P-gp inhibitor quinine, 6 cinchona analogues were shown to inhibit calcein-AM efflux. Interestingly, quinine and didehydroquinine exhibited a marginally increased toxicity against the multidrug resistant Dx5 cells. Collateral sensitivity of the MDR cell line was more pronounced when the cinchona thiosquaramide was complexed with Cu(II) acetate. Based on the results, cinchona derivatives are good anticancer candidates for further drug development.
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Affiliation(s)
- Szonja Polett Pósa
- Department of Organic Chemistry & Technology, Budapest University of Technology & Economics, Műegyetem rakpart 3, H-1111 Budapest, Hungary; Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary
| | - Gyula Dargó
- Department of Organic Chemistry & Technology, Budapest University of Technology & Economics, Műegyetem rakpart 3, H-1111 Budapest, Hungary
| | - Sándor Nagy
- Department of Organic Chemistry & Technology, Budapest University of Technology & Economics, Műegyetem rakpart 3, H-1111 Budapest, Hungary
| | - Péter Kisszékelyi
- Department of Organic Chemistry & Technology, Budapest University of Technology & Economics, Műegyetem rakpart 3, H-1111 Budapest, Hungary
| | - Zsófia Garádi
- Department of Pharmacognosy Semmelweis University, Üllői út. 26, H-1085 Budapest, Hungary
| | - Lilla Hámori
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary
| | - Gergely Szakács
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary; Institute of Cancer Research, Medical University Vienna, Vienna, Austria
| | - József Kupai
- Department of Organic Chemistry & Technology, Budapest University of Technology & Economics, Műegyetem rakpart 3, H-1111 Budapest, Hungary.
| | - Szilárd Tóth
- Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary.
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Koudijs KKM, Terwisscha van Scheltinga AGT, Böhringer S, Schimmel KJM, Guchelaar HJ. Personalised drug repositioning for Clear Cell Renal Cell Carcinoma using gene expression. Sci Rep 2018; 8:5250. [PMID: 29588458 PMCID: PMC5869697 DOI: 10.1038/s41598-018-23195-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 03/07/2018] [Indexed: 02/02/2023] Open
Abstract
Reversal of cancer gene expression is predictive of therapeutic potential and can be used to find new indications for existing drugs (drug repositioning). Gene expression reversal potential is currently calculated, in almost all studies, by pre-aggregating all tumour samples into a single group signature or a limited number of molecular subtype signatures. Here, we investigate whether drug repositioning based on individual tumour sample gene expression signatures outperforms the use of tumour group and subtype signatures. The tumour signatures were created using 534 tumour samples and 72 matched normal samples from 530 clear cell renal cell carcinoma (ccRCC) patients. More than 20,000 drug signatures were extracted from the CMAP and LINCS databases. We show that negative enrichment of individual tumour samples correlated (Spearman's rho = 0.15) much better with the amount of differentially expressed genes in drug signatures than with the tumour group signature (Rho = 0.08) and the 4 tumour subtype signatures (Rho 0.036-0.11). Targeted drugs used against ccRCC, such as sirolimus and temsirolimus, which could not be identified with the pre-aggregated tumour signatures could be recovered using individual sample analysis. Thus, drug repositioning can be personalized by taking into account the gene expression profile of the individual's tumour sample.
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Affiliation(s)
- Karel K M Koudijs
- Department of Clinical Pharmacy & Toxicology, Leiden University Medical Centre, Leiden, The Netherlands
| | | | - Stefan Böhringer
- Department of Medical Statistics, Leiden University Medical Centre, Leiden, The Netherlands
| | - Kirsten J M Schimmel
- Department of Clinical Pharmacy & Toxicology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Henk-Jan Guchelaar
- Department of Clinical Pharmacy & Toxicology, Leiden University Medical Centre, Leiden, The Netherlands.
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5
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Khan T, Gurav P. PhytoNanotechnology: Enhancing Delivery of Plant Based Anti-cancer Drugs. Front Pharmacol 2018; 8:1002. [PMID: 29479316 PMCID: PMC5811929 DOI: 10.3389/fphar.2017.01002] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Accepted: 12/29/2017] [Indexed: 01/03/2023] Open
Abstract
Natural resources continue to be an invaluable source of new, novel chemical entities of therapeutic utility due to the vast structural diversity observed in them. The quest for new and better drugs has witnessed an upsurge in exploring and harnessing nature especially for discovery of antimicrobial, antidiabetic, and anticancer agents. Nature has historically provide us with potent anticancer agents which include vinca alkaloids [vincristine (VCR), vinblastine, vindesine, vinorelbine], taxanes [paclitaxel (PTX), docetaxel], podophyllotoxin and its derivatives [etoposide (ETP), teniposide], camptothecin (CPT) and its derivatives (topotecan, irinotecan), anthracyclines (doxorubicin, daunorubicin, epirubicin, idarubicin), and others. In fact, half of all the anti-cancer drugs approved internationally are either natural products or their derivatives and were developed on the basis of knowledge gained from small molecules or macromolecules that exist in nature. Three new anti-cancer drugs introduced in 2007, viz. trabectedin, epothilone derivative ixabepilone, and temsirolimus were obtained from microbial sources. Selective drug targeting is the need of the current therapeutic regimens for increased activity on cancer cells and reduced toxicity to normal cells. Nanotechnology driven modified drugs and drug delivery systems are being developed and introduced in the market for better cancer treatment and management with good results. The use of nanoparticulate drug carriers can resolve many challenges in drug delivery to the cancer cells that includes: improving drug solubility and stability, extending drug half-lives in the blood, reducing adverse effects in non-target organs, and concentrating drugs at the disease site. This review discusses the scientific ventures and explorations involving application of nanotechnology to some selected plant derived molecules. It presents a comprehensive review of formulation strategies of phytoconstituents in development of novel delivery systems like liposomes, functionalized nanoparticles (NPs), application of polymer conjugates, as illustrated in the graphical abstract along with their advantages over conventional drug delivery systems supported by enhanced biological activity in in vitro and in vivo anticancer assays.
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Affiliation(s)
- Tabassum Khan
- Pharmaceutical Chemistry and Quality Assurance, SVKM's Dr. Bhanuben Nanavati College of Pharmacy, Mumbai, India
| | - Pranav Gurav
- Quality Assurance, Alkem Laboratories Ltd., Mumbai, India
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Edwardson DW, Boudreau J, Mapletoft J, Lanner C, Kovala AT, Parissenti AM. Inflammatory cytokine production in tumor cells upon chemotherapy drug exposure or upon selection for drug resistance. PLoS One 2017; 12:e0183662. [PMID: 28915246 PMCID: PMC5600395 DOI: 10.1371/journal.pone.0183662] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Accepted: 08/08/2017] [Indexed: 01/08/2023] Open
Abstract
Tumor Necrosis Factor alpha (TNF-α) has been shown to be released by tumor cells in response to docetaxel, and lipopolysaccharides (LPS), the latter through activation of toll-like receptor 4 (TLR4). However, it is unclear whether the former involves TLR4 receptor activation through direct binding of the drug to TLR4 at the cell surface. The current study was intended to better understand drug-induced TNF-α production in tumor cells, whether from short-term drug exposure or in cells selected for drug resistance. ELISAs were employed to measure cytokine release from breast and ovarian tumor cells in response to several structurally distinct chemotherapy agents and/or TLR4 agonists or antagonists. Drug uptake and drug sensitivity studies were also performed. We observed that several drugs induced TNF-αrelease from multiple tumor cell lines. Docetaxel-induced cytokine production was distinct from that of LPS in both MyD88-positive (MCF-7) and MyD88-deficient (A2780) cells. The acquisition of docetaxel resistance was accompanied by increased constitutive production of TNF-αand CXCL1, which waned at higher levels of resistance. In docetaxel-resistant MCF-7 and A2780 cell lines, the production of TNF-α could not be significantly augmented by docetaxel without the inhibition of P-gp, a transporter protein that promotes drug efflux from tumor cells. Pretreatment of tumor cells with LPS sensitized MyD88-positive cells (but not MyD88-deficient) to docetaxel cytotoxicity in both drug-naive and drug-resistant cells. Our findings suggest that taxane-induced inflammatory cytokine production from tumor cells depends on the duration of exposure, requires cellular drug-accumulation, and is distinct from the LPS response seen in breast tumor cells. Also, stimulation of the LPS-induced pathway may be an attractive target for treatment of drug-resistant disease.
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Affiliation(s)
- Derek W. Edwardson
- Ph.D. Program in Biomolecular Science, Laurentian University, Sudbury, Ontario, Canada
| | - Justin Boudreau
- Department of Biology, Laurentian University, Sudbury, Ontario, Canada
| | - Jonathan Mapletoft
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Carita Lanner
- Ph.D. Program in Biomolecular Science, Laurentian University, Sudbury, Ontario, Canada
- Department of Biology, Laurentian University, Sudbury, Ontario, Canada
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
- Division of Medical Sciences, Northern Ontario School of Medicine, Sudbury, Ontario, Canada
| | - A. Thomas Kovala
- Ph.D. Program in Biomolecular Science, Laurentian University, Sudbury, Ontario, Canada
- Department of Biology, Laurentian University, Sudbury, Ontario, Canada
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
- Division of Medical Sciences, Northern Ontario School of Medicine, Sudbury, Ontario, Canada
| | - Amadeo M. Parissenti
- Ph.D. Program in Biomolecular Science, Laurentian University, Sudbury, Ontario, Canada
- Department of Biology, Laurentian University, Sudbury, Ontario, Canada
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
- Division of Medical Sciences, Northern Ontario School of Medicine, Sudbury, Ontario, Canada
- Health Sciences North Research Institute, Sudbury, Ontario, Canada
- Faculty of Medicine, Division of Oncology, University of Ottawa, Ottawa, Ontario, Canada
- * E-mail:
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Podolski-Renić A, Bősze S, Dinić J, Kocsis L, Hudecz F, Csámpai A, Pešić M. Ferrocene–cinchona hybrids with triazolyl-chalcone linkers act as pro-oxidants and sensitize human cancer cell lines to paclitaxel. Metallomics 2017; 9:1132-1141. [DOI: 10.1039/c7mt00183e] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Epimeric ferrocene–quinidine hybrids with triazolyl-chalcone linkers act as pro-oxidative agents and autophagy modulators in paclitaxel resistant cancer cells.
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Affiliation(s)
- Ana Podolski-Renić
- Department of Neurobiology
- Institute for Biological Research “Siniša Stanković” (IBISS)
- University of Belgrade
- Belgrade
- Serbia
| | - Szilvia Bősze
- MTA-ELTE Research Group of Peptide Chemistry
- Eötvös Loránd University
- Budapest
- Hungary
| | - Jelena Dinić
- Department of Neurobiology
- Institute for Biological Research “Siniša Stanković” (IBISS)
- University of Belgrade
- Belgrade
- Serbia
| | - László Kocsis
- Department of Organic Chemistry
- Eötvös Loránd University (ELTE)
- Budapest
- Hungary
| | - Ferenc Hudecz
- MTA-ELTE Research Group of Peptide Chemistry
- Eötvös Loránd University
- Budapest
- Hungary
- Department of Organic Chemistry
| | - Antal Csámpai
- Department of Inorganic Chemistry
- Eötvös Loránd University (ELTE)
- Budapest
- Hungary
| | - Milica Pešić
- Department of Neurobiology
- Institute for Biological Research “Siniša Stanković” (IBISS)
- University of Belgrade
- Belgrade
- Serbia
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8
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Kocsis L, Szabó I, Bősze S, Jernei T, Hudecz F, Csámpai A. Synthesis, structure and in vitro cytostatic activity of ferrocene-Cinchona hybrids. Bioorg Med Chem Lett 2015; 26:946-949. [PMID: 26739780 DOI: 10.1016/j.bmcl.2015.12.059] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2015] [Revised: 12/14/2015] [Accepted: 12/17/2015] [Indexed: 10/22/2022]
Abstract
Exploring copper(I)- and ruthenium(II)-catalyzed azide-alkyne cycloadditions and a Sonogashira protocol, novel cytostatic ferrocene-cinchona hybrids were synthetized displaying significant in vitro activity on HepG-2 and HT-29 cells. Preliminary SAR studies disclosed that compounds incorporating linkers with 1,2,3-triazole and chalchone residues can be considered as promising lead structures. According to the best of our knowledge this is the first letter on the incorporation of ferrocene nucleus in the reputed cinchona family via triazole and chalcone linkers with established pharmaceutical profile.
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Affiliation(s)
- László Kocsis
- MTA-ELTE Research Group of Peptide Chemistry, Budapest Pázmány P. sétány 1/A, H-1117, Hungary
| | - Ildikó Szabó
- Department of Organic Chemistry, Eötvös Loránd University (ELTE), Budapest Pázmány P. sétány 1/A, H-1117, Hungary
| | - Szilvia Bősze
- Department of Organic Chemistry, Eötvös Loránd University (ELTE), Budapest Pázmány P. sétány 1/A, H-1117, Hungary
| | - Tamás Jernei
- Department of Inorganic Chemistry, Eötvös Loránd University (ELTE), Budapest Pázmány P. sétány 1/A, H-1117, Hungary
| | - Ferenc Hudecz
- MTA-ELTE Research Group of Peptide Chemistry, Budapest Pázmány P. sétány 1/A, H-1117, Hungary; Department of Organic Chemistry, Eötvös Loránd University (ELTE), Budapest Pázmány P. sétány 1/A, H-1117, Hungary
| | - Antal Csámpai
- Department of Inorganic Chemistry, Eötvös Loránd University (ELTE), Budapest Pázmány P. sétány 1/A, H-1117, Hungary.
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Trendowski M, Christen TD, Acquafondata C, Fondy TP. Effects of cytochalasin congeners, microtubule-directed agents, and doxorubicin alone or in combination against human ovarian carcinoma cell lines in vitro. BMC Cancer 2015; 15:632. [PMID: 26357852 PMCID: PMC4566295 DOI: 10.1186/s12885-015-1619-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 08/21/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Although the actin cytoskeleton is vital for carcinogenesis and subsequent pathology, no microfilament-directed agent has been approved for cancer chemotherapy. One of the most studied classes of microfilament-directed agents has been the cytochalasins, mycotoxins known to disrupt the formation of actin polymers. In the present study, we sought to determine the effects of cytochalasin congeners toward human drug sensitive and multidrug resistant cell lines. METHODS SKOV3 human ovarian carcinoma and several multidrug resistant derivatives were tested for sensitivity against a panel of nine cytochalasin congeners, as well as three clinically approved chemotherapeutic agents (doxorubicin, paclitaxel, and vinblastine). In addition, verapamil, a calcium ion channel blocker known to reverse P-glycoprotein (P-gp) mediated drug resistance, was used in combination with multiple cytochalasin congeners to determine whether drug sensitivity could be increased. RESULTS While multidrug resistant SKVLB1 had increased drug tolerance (was more resistant) to most cytochalasin congeners in comparison to drug sensitive SKOV3, the level of resistance was 10 to 1000-fold less for the cytochalasins than for any of the clinically approved agents. While cytochalasins did not appear to alter the expression of ATP binding cassette (ABC) transporters, several cytochalasins appeared to inhibit the activity of ABC transporter-mediated efflux of rhodamine 123 (Rh123), suggesting that these congeners do have affinity for drug efflux pumps. Cytochalasins also appeared to significantly decrease the F/G-actin ratio in both drug sensitive and drug resistant cells, indicative of marked microfilament inhibition. The cytotoxicity of most cytochalasin congeners could be increased with the addition of verapamil, and the drug sensitivity of resistant SKVLB1 to the clinically approved antineoplastic agents could be increased with the addition of cytochalasins. As assessed by isobolographic analysis and Chou-Talalay statistics, cytochalasin B and 21,22-dihydrocytochalasin B (DiHCB) demonstrated notable synergy with doxorubicin and paclitaxel, warranting further investigation in a tumor-bearing mammalian model. CONCLUSION Cytochalasins appear to inhibit the activity of P-gp and potentially other ABC transporters, and may have novel activity against multidrug resistant neoplastic cells that overexpress drug efflux proteins.
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Affiliation(s)
- Matthew Trendowski
- Department of Biology, Syracuse University, 107 College Place, Syracuse, NY, 13244, USA.
| | - Timothy D Christen
- Department of Biology, Syracuse University, 107 College Place, Syracuse, NY, 13244, USA.
| | | | - Thomas P Fondy
- Department of Biology, Syracuse University, 107 College Place, Syracuse, NY, 13244, USA.
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Bhuiyan MPI, Aryal MP, Janic B, Karki K, Varma NRS, Ewing JR, Arbab AS, Ali MM. Concentration-independent MRI of pH with a dendrimer-based pH-responsive nanoprobe. CONTRAST MEDIA & MOLECULAR IMAGING 2015; 10:481-6. [PMID: 26173742 DOI: 10.1002/cmmi.1651] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Revised: 03/15/2015] [Accepted: 05/04/2015] [Indexed: 12/27/2022]
Abstract
The measurement of extracellular pH (pHe ) has significant clinical value for pathological diagnoses and for monitoring the effects of pH-altering therapies. One of the major problems of measuring pHe with a relaxation-based MRI contrast agent is that the longitudinal relaxivity depends on both pH and the concentration of the agent, requiring the use of a second pH-unresponsive agent to measure the concentration. Here we tested the feasibility of measuring pH with a relaxation-based dendritic MRI contrast agent in a concentration-independent manner at clinically relevant field strengths. The transverse and longitudinal relaxation times in solutions of the contrast agent (GdDOTA-4AmP)44 -G5, a G5-PAMAM dendrimer-based MRI contrast agent in water, were measured at 3 T and 7 T magnetic field strengths as a function of pH. At 3 T, longitudinal relaxivity (r1 ) increased from 7.91 to 9.65 mM(-1) s(-1) (on a per Gd(3+) basis) on changing pH from 8.84 to 6.35. At 7 T, r1 relaxivity showed pH response, albeit at lower mean values; transverse relaxivity (r2 ) remained independent of pH and magnetic field strengths. The longitudinal relaxivity of (GdDOTA-4AmP)44 -G5 exhibited a strong and reversible pH dependence. The ratio of relaxation rates R2 /R1 also showed a linear relationship in a pH-responsive manner, and this pH response was independent of the absolute concentration of (GdDOTA-4AmP)44 -G5 agent. Importantly, the nanoprobe (GdDOTA-4AmP)44 -G5 shows pH response in the range commonly found in the microenvironment of solid tumors.
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Affiliation(s)
| | | | | | | | | | | | - Ali S Arbab
- Department of Biochemistry and Molecular Biology, Georgia Regents University, Augusta, GA, USA
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11
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McCarthy M, Auda G, Agrawal S, Taylor A, Backstrom Z, Mondal D, Moroz K, Dash S. In vivo anticancer synergy mechanism of doxorubicin and verapamil combination treatment is impaired in BALB/c mice with metastatic breast cancer. Exp Mol Pathol 2014; 97:6-15. [DOI: 10.1016/j.yexmp.2014.04.013] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 04/21/2014] [Indexed: 11/28/2022]
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12
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Dual agent loaded PLGA nanoparticles enhanced antitumor activity in a multidrug-resistant breast tumor eenograft model. Int J Mol Sci 2014; 15:2761-72. [PMID: 24552875 PMCID: PMC3958880 DOI: 10.3390/ijms15022761] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Revised: 02/10/2014] [Accepted: 02/11/2014] [Indexed: 02/08/2023] Open
Abstract
Multidrug-resistant breast cancers have limited and ineffective clinical treatment options. This study aimed to develop PLGA nanoparticles containing a synergistic combination of vincristine and verapamil to achieve less toxicity and enhanced efficacy on multidrug-resistant breast cancers. The 1:250 molar ratio of VCR/VRP showed strong synergism with the reversal index of approximately 130 in the multidrug-resistant MCF-7/ADR cells compared to drug-sensitive MCF-7 cells. The lyophilized nanoparticles could get dispersed quickly with the similar size distribution, zeta potential and encapsulation efficiency to the pre-lyophilized nanoparticles suspension, and maintain the synergistic in vitro release ratio of drugs. The co-encapsulated nanoparticle formulation had lower toxicity than free vincristine/verapamil combinations according to the acute-toxicity test. Furthermore, the most effective tumor growth inhibition in the MCF-7/ADR human breast tumor xenograft was observed in the co-delivery nanoparticle formulation group in comparison with saline control, free vincristine, free vincristine/verapamil combinations and single-drug nanoparticle combinations. All the data demonstrated that PLGANPs simultaneously loaded with chemotherapeutic drug and chemosensitizer might be one of the most potential formulations in the treatment of multidrug-resistant breast cancer in clinic.
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Moon JW, Lee SK, Lee JO, Kim N, Lee YW, Kim SJ, Kang HJ, Kim J, Kim HS, Park SH. Identification of novel hypermethylated genes and demethylating effect of vincristine in colorectal cancer. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2014; 33:4. [PMID: 24393480 PMCID: PMC3923411 DOI: 10.1186/1756-9966-33-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 01/02/2014] [Indexed: 12/29/2022]
Abstract
BACKGROUND Colorectal cancer (CRC) arises as a consequence of genetic events such as gene mutation and epigenetic alteration. The aim of this study was to identify new hypermethylated candidate genes and methylation-based therapeutic targets using vincristine in CRC. METHODS We analyzed the methylation status of 27,578 CpG sites spanning more than 14,000 genes in CRC tissues compared with adjacent normal tissues and normal colon tissues using Illumina bead chip array. Twenty-one hypermethylated genes and 18 CpG island methylator phenotype markers were selected as candidate genes. The methylation status of 39 genes was validated by quantitative methylation-specific polymerase chain reaction in CRC tissues, adjacent normal tissues, normal colon cells, and three CRC cell lines. Of these, 29 hypermethylated candidate genes were investigated using the demethylating effects of 5-aza-2'-deoxycytidine (5-aza-dC) and vincristine in CRC cells. RESULTS Thirty-two out of 39 genes were hypermethylated in CRC tissues compared with adjacent normal tissues. Vincristine induced demethylation of methylated genes in CRC cells to the same extent as 5-aza-dC. The mRNA expression of AKR1B1, CHST10, ELOVL4, FLI1, SOX5, STK33, and ZNF304 was restored by treatment with 5-aza-dC and vincristine. CONCLUSION These results suggest that these novel hypermethylated genes AKR1B1, CHST10, ELOVL4, SOX5, STK33, and ZNF304 may be potential methylation biomarkers and therapeutic targets of vincristine in CRC.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Sun-Hwa Park
- Department of Anatomy, Institute of Human Genetics, Korea University College of Medicine, 126-1, Anam-dong 5-ga, Seongbuk-gu, Seoul 136-705, Republic of Korea.
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14
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Chemotherapy-induced peripheral neurotoxicity (CIPN): An update. Crit Rev Oncol Hematol 2012; 82:51-77. [DOI: 10.1016/j.critrevonc.2011.04.012] [Citation(s) in RCA: 377] [Impact Index Per Article: 31.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Revised: 04/21/2011] [Accepted: 04/28/2011] [Indexed: 11/21/2022] Open
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Károlyi BI, Bősze S, Orbán E, Sohár P, Drahos L, Gál E, Csámpai A. Acylated mono-, bis- and tris- cinchona-based amines containing ferrocene or organic residues: synthesis, structure and in vitro antitumor activity on selected human cancer cell lines. Molecules 2012; 17:2316-29. [PMID: 22367026 PMCID: PMC6269053 DOI: 10.3390/molecules17032316] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Revised: 02/13/2012] [Accepted: 02/14/2012] [Indexed: 11/24/2022] Open
Abstract
A series of novel functionalized mono-, bis- and tris-(S)-{[(2S,4R,8R)-8-ethyl-quinuclidin-2-yl](6-methoxyquinolin-4-yl)}methanamines including ferrocene-containing derivatives was obtained by the reaction of the precursor amine with a variety of acylation agents. Their in vitro antitumor activity was investigated against human leukemia (HL-60), human neuroblastoma (SH-SY5Y), human hepatoma (HepG2) and human breast cancer (MCF-7) cells by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)-assay and the 50% inhibitory concentration (IC50) values were determined. Our data indicate that the precursor amine has no antitumor activity in vitro, but the bis-methanamines with ureido-, thioureido and amide-type linkers display attractive in vitro cytotoxicity and cytostatic effects on HL-60, HepG2, MCF-7 and SH-SY5Y cells. Besides 1H- and 13C-NMR methods the structures of the new model compounds were also studied by DFT calculations.
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Affiliation(s)
- Benedek Imre Károlyi
- Institute of Chemistry, Eötvös Loránd University, P. O. B. 32, H-1518 Budapest-112, Hungary; (B.I.K.); (P.S.)
| | - Szilvia Bősze
- Research Group of Peptide Chemistry, Hungarian Academy of Sciences, Eötvös Loránd Universiy, P. O. B. 32, H-1518 Budapest-112, Hungary; (S.B.); (E.O.)
| | - Erika Orbán
- Research Group of Peptide Chemistry, Hungarian Academy of Sciences, Eötvös Loránd Universiy, P. O. B. 32, H-1518 Budapest-112, Hungary; (S.B.); (E.O.)
| | - Pál Sohár
- Institute of Chemistry, Eötvös Loránd University, P. O. B. 32, H-1518 Budapest-112, Hungary; (B.I.K.); (P.S.)
| | - László Drahos
- Chemres Institute of Structural Chemistry Chemical Research Center, Hungarian Academy of Sciences, H-1025 Budapest, Pusztaszeri str. 59-67, Hungary;
| | - Emese Gál
- Faculty of Chemistry and Chemical Engineering, Babes-Bolyai University, Arany János str. 11, 400028 Cluj-Napoca, Romania;
| | - Antal Csámpai
- Institute of Chemistry, Eötvös Loránd University, P. O. B. 32, H-1518 Budapest-112, Hungary; (B.I.K.); (P.S.)
- Author to whom correspondence should be addressed; ; Tel.: +36-1-372-2500 / 6591; Fax: +36-1-372-2592
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16
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Ling G, Zhang P, Sun J, Zhang W, Fu Q, Zhang T, Deng Y, He Z. An LC-MS/MS method for simultaneous determination of vincristine and verapamil in rat plasma after oral administration of a dual agent formulation. Biomed Chromatogr 2010; 25:963-9. [DOI: 10.1002/bmc.1565] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2010] [Revised: 09/25/2010] [Accepted: 09/28/2010] [Indexed: 11/11/2022]
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Patel KJ, Tannock IF. The influence of P-glycoprotein expression and its inhibitors on the distribution of doxorubicin in breast tumors. BMC Cancer 2009; 9:356. [PMID: 19807929 PMCID: PMC2770566 DOI: 10.1186/1471-2407-9-356] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2009] [Accepted: 10/06/2009] [Indexed: 11/10/2022] Open
Abstract
Background Anti-cancer drugs access solid tumors via blood vessels, and must penetrate tumor tissue to reach all cancer cells. Previous studies have demonstrated steep gradients of decreasing doxorubicin fluorescence with increasing distance from blood vessels, such that many tumor cells are not exposed to drug. Studies using multilayered cell cultures show that increased P-glycoprotein (PgP) is associated with better penetration of doxorubicin, while PgP inhibitors decrease drug penetration in tumor tissue. Here we evaluate the effect of PgP expression on doxorubicin distribution in vivo. Methods Mice bearing tumor sublines with either high or low expression of PgP were treated with doxorubicin, with or without pre-treatment with the PgP inhibitors verapamil or PSC 833. The distribution of doxorubicin in relation to tumor blood vessels was quantified using immunofluorescence. Results Our results indicate greater uptake of doxorubicin by cells near blood vessels in wild type as compared to PgP-overexpressing tumors, and pre-treatment with verapamil or PSC 833 increased uptake in PgP-overexpressing tumors. However, there were steeper gradients of decreasing doxorubicin fluorescence in wild-type tumors compared to PgP overexpressing tumors, and treatment of PgP overexpressing tumors with PgP inhibitors led to steeper gradients and greater heterogeneity in the distribution of doxorubicin. Conclusion PgP inhibitors increase uptake of doxorubicin in cells close to blood vessels, have little effect on drug uptake into cells at intermediate distances, and might have a paradoxical effect to decrease doxorubicin uptake into distal cells. This effect probably contributes to the limited success of PgP inhibitors in clinical trials.
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Affiliation(s)
- Krupa J Patel
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada.
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18
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Chen SZ, Jiang M, Zhen YS. HERG K+ channel expression-related chemosensitivity in cancer cells and its modulation by erythromycin. Cancer Chemother Pharmacol 2005; 56:212-20. [PMID: 15812674 DOI: 10.1007/s00280-004-0960-5] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2004] [Accepted: 10/15/2004] [Indexed: 11/25/2022]
Abstract
PURPOSE Previous studies have found that the HERG K+ channel is highly expressed in some cancers. In the study reported here, we investigated HERG expression in various cancer cell lines, its correlation with chemosensitivity to vincristine, paclitaxel, and hydroxy-camptothecin, and its biochemical modulation. METHODS The MTT assay and clonogenic assay were used to detect the cytotoxicity of anticancer drugs in vitro. HERG expression was analyzed by Western blotting or immunocytochemistry. Gene transfection was used to examine the changes in HERG-related chemosensitivity. Cell cycle phase distribution was detected by flow cytometry and drug combinations were evaluated by the MTT assay. RESULTS HERG expression levels differed widely between various human cancer cell lines and HT-29 cells expressing high levels of HERG were more sensitive than A549 cells expressing low levels of HERG to vincristine, paclitaxel, and hydroxy-camptothecin. In terms of IC50, the chemosensitivities of herg-transfected A549 cells to vincristine, paclitaxel and hydroxy-camptothecin were significantly increased. However, for cisplatin and 5-fluorouracil, no significant difference between herg-transfected A549 cells and parent A549 cells was detected. Erythromycin, a HERG K+ channel blocker, suppressed the growth of various cancer cells and the potency was correlated with HERG expression levels. Combinations of erythromycin and vincristine, paclitaxel or hydroxy-camptothecin showed synergy in cytotoxicity to HT-29 cells. Erythromycin also enhanced the G2/M arrest induced by vincristine in HT-29 cells. There were synergistic effects between erythromycin and vincristine, paclitaxel, and hydroxy-camptothecin, and chemosensitivity was correlated with HERG expression level. CONCLUSIONS HERG expression levels and chemosensitivity were positively correlated for vincristine, paclitaxel, and hydroxy-camptothecin. Erythromycin was active as a modulator. These results suggest that HERG may serve as a molecular marker and modulating target for individualized cancer therapy.
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Affiliation(s)
- Shu-Zhen Chen
- Department of Oncology, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, China,
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19
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Huang JB, Kindzelskii AL, Clark AJ, Petty HR. Identification of Channels Promoting Calcium Spikes and Waves in HT1080 Tumor Cells. Cancer Res 2004; 64:2482-9. [PMID: 15059902 DOI: 10.1158/0008-5472.can-03-3501] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Intracellular Ca(2+) signals have been associated with cell polarization and locomotion. As cell motility underlies metastasis, we have sought to better characterize the Ca(2+) signaling events in HT1080 fibrosarcoma cells. We have tested the hypothesis that low voltage-activated (LVA) and nonvoltage-gated (NVG) channels of HT1080 cells participate in dynamic Ca(2+)-signaling events leading to cell migration and invasion. Immunofluorescence microscopy has shown that HT1080 cells express LVA T-type Ca(2+) channels uniformly about the cell periphery, whereas the transient receptor potential-1 (a NVG cation channel) protein appears as punctate spots about a cell's periphery. HT1080 cells exhibit periodic intracellular Ca(2+) spikes. High-speed imaging revealed that the Ca(2+) spikes were composed of a single Ca(2+) wave traveling unidirectionally about the periphery of the cytoplasm in a clockwise fashion (as viewed from basal to apical surfaces). The T-type Ca(2+) channel blocker mibefradil inhibited Ca(2+) spikes and waves on cells and, in parallel, inhibited cell motility and invasion in a dose-dependent manner. Similar changes were noted with the NVG cation channel blockers Gd(3+) and carboxyamido-triazole. The combination of LVA and NVG blockers further reduced Matrigel invasiveness. However, the Ca(2+) channel blockers nicardipine, SKF96365, diltiazem, and verapamil had no effect at appropriate doses. These results indicate that certain LVA and NVG channels regulate HT1080 cell motility. In addition to providing novel information regarding cancer cell motility, we suggest that it may be possible to design drugs that inhibit a key Ca(2+) wave, thereby enhancing the efficacy of emerging therapeutic protocols.
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Affiliation(s)
- Ji-Biao Huang
- Department of Ophthalmology and Visual Sciences, The University of Michigan Medical School, Ann Arbor, Michigan 48105, USA
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20
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Mahoney BP, Raghunand N, Baggett B, Gillies RJ. Tumor acidity, ion trapping and chemotherapeutics. I. Acid pH affects the distribution of chemotherapeutic agents in vitro. Biochem Pharmacol 2003; 66:1207-18. [PMID: 14505800 DOI: 10.1016/s0006-2952(03)00467-2] [Citation(s) in RCA: 244] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Resistance to anti-cancer chemotherapies often leads to regional failure, and can be caused by biochemical and/or physiological mechanisms. Biochemical mechanisms include the overexpression of resistance-conferring proteins. In contrast, physiological resistance involves the tumor microenvironment, and can be caused by poor perfusion, hypoxia and/or acidity. This communication investigates the role of tumor acidity in resistance to a panel of chemotherapeutic agents commonly used against breast cancer, such as anthracyclines, taxanes, anti-metabolites and alkylating agents. The effects of pH on the cytotoxicity of these agents were determined, and ion trapping was confirmed by monitoring the effect of pH on the cellular uptake of radiolabeled anthracyclines. Furthermore, pH-dependent cytotoxicity and uptake were compared between parental drug sensitive MCF-7 cells and variants overexpressing p-glycoprotein (MDR-1) and Breast Cancer Resistance Protein. These data indicate that the magnitude of physiological resistance from pH-dependent ion trapping is comparable to biochemical resistance caused by overexpression of drug efflux pumps. Hence, microenvironment-based ion trapping is a significant barrier to anthracycline-based chemotherapy and can itself be a therapeutic target to enhance the efficacy of existing chemotherapies.
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Affiliation(s)
- Brent P Mahoney
- Department of Biochemistry and Cancer Biology Program, Arizona Cancer Center, University of Arizona Health Sciences Center, Tucson, AZ 85724-5024, USA
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Artym VV, Petty HR. Molecular proximity of Kv1.3 voltage-gated potassium channels and beta(1)-integrins on the plasma membrane of melanoma cells: effects of cell adherence and channel blockers. J Gen Physiol 2002; 120:29-37. [PMID: 12084773 PMCID: PMC2311400 DOI: 10.1085/jgp.20028607] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Tumor cell membranes have multiple components that participate in the process of metastasis. The present study investigates the physical association of beta1-integrins and Kv1.3 voltage-gated potassium channels in melanoma cell membranes using resonance energy transfer (RET) techniques. RET between donor-labeled anti-beta1-integrin and acceptor-labeled anti-Kv1.3 channels was detected on LOX cells adherent to glass and fibronectin-coated coverslips. However, RET was not observed on LOX cells in suspension, indicating that molecular proximity of these membrane molecules is adherence-related. Several K(+) channel blockers, including tetraethylammonium, 4-aminopyridine, and verapamil, inhibited RET between beta1-integrins and Kv1.3 channels. However, the irrelevant K(+) channel blocker apamin had no effect on RET between beta1-integrins and Kv1.3 channels. Based on these findings, we speculate that the lateral association of Kv1.3 channels with beta1-integrins contributes to the regulation of integrin function and that channel blockers might affect tumor cell behavior by influencing the assembly of supramolecular structures containing integrins.
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Affiliation(s)
- Vira V Artym
- Department of Biological Sciences, Wayne State University, Detroit, MI 48202, USA
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Mukanganyama S, Widersten M, Naik YS, Mannervik B, Hasler JA. Inhibition of glutathione S-transferases by antimalarial drugs possible implications for circumventing anticancer drug resistance. Int J Cancer 2002; 97:700-5. [PMID: 11807801 DOI: 10.1002/ijc.10054] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A strategy to overcome multidrug resistance in cancer cells involves treatment with a combination of the antineoplastic agent and a chemomodulator that inhibits the activity of the resistance-causing protein. The aim of our study was to investigate the effects of antimalarial drugs on human recombinant glutathione S-transferase (GSTs) activity in the context of searching for effective and clinically acceptable inhibitors of these enzymes. Human recombinant GSTs heterologously expressed in Escherichia coli were used for inhibition studies. GST A1-1 activity was inhibited by artemisinin with an IC(50) of 6 microM, whilst GST M1-1 was inhibited by quinidine and its diastereoisomer quinine with IC(50)s of 12 microM and 17 microM, respectively. GST M3-3 was inhibited by tetracycline only with an IC(50) of 47 microM. GST P1-1 was the most susceptible enzyme to inhibition by antimalarials with IC(50) values of 1, 2, 1, 4, and 13 microM for pyrimethamine, artemisinin, quinidine, quinine and tetracycline, respectively. The IC(50) values obtained for artemisinin, quinine, quinidine and tetracycline are below peak plasma concentrations obtained during therapy of malaria with these drugs. It seems likely, therefore, that GSTs may be inhibited in vivo at doses normally used in clinical practice. Using the substrate ethacrynic acid, a diuretic drug also used as a modulator to overcome drug resistance in tumour cells, GST P1-1 activity was inhibited by tetracycline, quinine, pyrimethamine and quinidine with IC(50) values of 18, 27, 45 and 70 microM, respectively. The ubiquitous expression of GSTs in different malignancies suggests that the addition of nontoxic reversing agents such as antimalarials could enhance the efficacy of a variety of alkylating agents.
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Lecci A, Meini S, Patacchini R, Tramontana M, Giuliani S, Criscuoli M, Maggi CA. Effect of dexamethasone on cyclophosphamide-induced cystitis in rats: lack of relation with bradykinin B1 receptor-mediated motor responses. Eur J Pharmacol 1999; 369:99-106. [PMID: 10204687 DOI: 10.1016/s0014-2999(99)00052-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We investigated the role of bradykinin B receptors in inducing urinary bladder contraction and maintaining bladder compliance in anaesthetized rats following cyclophosphamide-induced bladder inflammation and the influence of dexamethasone treatment on these responses. In the group treated with cyclophosphamide the amplitude of the contraction induced by the selective bradykinin B1 receptor agonist des-Arg9-bradykinin was larger than that in controls and dexamethasone prevented the up-regulation of this response induced by inflammation. The specific binding of [3H]des-Arg10-kallidin to bladder membranes was only detected in cyclophosphamide-treated rats: this binding was prevented by dexamethasone pretreatment. The bladder contraction induced by des-Arg9-bradykinin in cyclophosphamide-treated rats was antagonized by the bradykinin B1 receptor antagonist des-Arg9-D-Arg-[Hyp3,Thi5,D-Tic7,Oic8]bradykinin (des-Arg10-Hoe 140). Cyclophosphamide treatment increased the bladder weight and dexamethasone reversed this effect. Bladder compliance was decreased in the bladder inflammation group and this effect was partially reversed by dexamethasone pretreatment. Neither des-Arg10-Hoe 140 nor the combined administration of des-Arg10Hoe 140 and the selective bradykinin B2 receptor antagonist D-Arg-[Hyp3,Thi5,D-Tic7,Oic8]bradykinin (Hoe 140) affected bladder compliance, thus excluding a role of kinins in the maintenance of bladder tone during inflammation. These results indicate that: (1) dexamethasone pretreatment ameliorates cyclophosphamide-induced bladder inflammation: (2) dexamethasone pretreatment prevents cyclophosphamide-induced up-regulation of bradykinin B receptors; (3) kinins do not contribute to the increased vesical tone during inflammation.
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Affiliation(s)
- A Lecci
- Pharmacology Department, Menarini Ricerche, Florence, Italy
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Raghunand N, Altbach MI, van Sluis R, Baggett B, Taylor CW, Bhujwalla ZM, Gillies RJ. Plasmalemmal pH-gradients in drug-sensitive and drug-resistant MCF-7 human breast carcinoma xenografts measured by 31P magnetic resonance spectroscopy. Biochem Pharmacol 1999; 57:309-12. [PMID: 9890558 DOI: 10.1016/s0006-2952(98)00306-2] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
31p Magnetic resonance spectroscopy (MRS) was employed to investigate tumor pH in xenografts of drug-sensitive and drug-resistant MCF-7 human breast carcinoma cells. Measured extracellular pH values were found to be lower than the intracellular pH in all three tumor types investigated. The magnitude of this acid-outside plasmalemmal pH gradient increased with increasing tumor size in tumors of two drug-resistant variants of MCF-7 cells, but not in tumors of the parent (drug-sensitive) cells. The partitioning of weak-base or weak-acid drug molecules across the plasma membrane of a tumor cell is dependent upon the acid-dissociation constant (pKa) of the drug as well as the plasmalemmal pH gradient. A large acid-outside pH gradient, such as those seen in MCF-7 xenografts, can exert a protective effect on the cell from weak-base drugs such as anthracyclines and Vinca alkaloids, which have pKa values of 7.5 to 9.5. The possibility of enhancing the therapeutic efficacy of weak-base drugs by dietary or metabolic manipulation of the extracellular pH, in order to reduce or reverse the plasmalemmal pH gradient, deserves investigation.
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Affiliation(s)
- N Raghunand
- Department of Biochemistry, University of Arizona Health Sciences Center, Tucson 85724-5042, USA
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Paul D, Cowan KH. Drug Resistance in Breast Cancer. Breast Cancer 1999. [DOI: 10.1007/978-1-59259-456-6_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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