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Hayat U, Elliott GT, Olszanski AJ, Altieri DC. Feasibility and safety of targeting mitochondria for cancer therapy – preclinical characterization of gamitrinib, a first-in-class, mitochondriaL-targeted small molecule Hsp90 inhibitor. Cancer Biol Ther 2022; 23:117-126. [PMID: 35129069 PMCID: PMC8820820 DOI: 10.1080/15384047.2022.2029132] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Mitochondria are key tumor drivers, but their suitability as a therapeutic target is unknown. Here, we report on the preclinical characterization of Gamitrinib (GA mitochondrial matrix inhibitor), a first-in-class anticancer agent that couples the Heat Shock Protein-90 (Hsp90) inhibitor 17-allylamino-geldanamycin (17-AAG) to the mitochondrial-targeting moiety, triphenylphosphonium. Formulated as a stable (≥24 weeks at −20°C) injectable suspension produced by microfluidization (<200 nm particle size), Gamitrinib (>99.5% purity) is heavily bound to plasma proteins (>99%), has intrinsic clearance from liver microsomes of 3.30 mL/min/g and minimally penetrates a Caco-2 intestinal monolayer. Compared to 17-AAG, Gamitrinib has slower clearance (85.6 ± 5.8 mL/min/kg), longer t1/2 (12.2 ± 1.55 h), mean AUC0-t of 783.1 ± 71.3 h∙ng/mL, and unique metabolism without generation of 17-AG. Concentrations of Gamitrinib that trigger tumor cell killing (IC50 ~1-4 µM) do not affect cytochrome P450 isoforms CYP1A2, CYP2A6, CYP2B6, CYP2C8 or ion channel conductance (Nav1.5, Kv4.3/KChIP2, Cav1.2, Kv1.5, KCNQ1/mink, HCN4, Kir2). Twice weekly IV administration of Gamitrinib to Sprague-Dawley rats or beagle dogs for up to 36 d is feasible. At dose levels of up to 5 (rats)- and 12 (dogs)-fold higher than therapeutically effective doses in mice (10 mg/kg), Gamitrinib treatment is unremarkable in dogs with no alterations in clinical-chemistry parameters, heart function, or tissue histology, and causes occasional inflammation at the infusion site and mild elevation of serum urea nitrogen in rats (≥10 mg/kg/dose). Therefore, targeting mitochondria for cancer therapy is feasible and well tolerated. A publicly funded, first-in-human phase I clinical trial of Gamitrinib in patients with advanced cancer is ongoing (ClinicalTrials.gov NCT04827810)
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Affiliation(s)
- Umar Hayat
- Pharmaceutical Advisors, LLC, Princeton, USA
| | | | - Anthony J. Olszanski
- Phase 1 Developmental Therapeutics Program, Department of Hematology/Oncology Fox Chase Cancer Center, Philadelphia
| | - Dario C. Altieri
- Immunology, Microenvironment and Metastasis Program, The Wistar Institute, Philadelphia, USA
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Hyperthermia enhances 17-DMAG efficacy in hepatocellular carcinoma cells with aggravated DNA damage and impaired G2/M transition. Sci Rep 2016; 6:38072. [PMID: 27909289 PMCID: PMC5133462 DOI: 10.1038/srep38072] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 10/20/2016] [Indexed: 02/06/2023] Open
Abstract
Due to the lack of effective treatment, hepatocellular carcinoma (HCC) is one of the malignancies with low survival rates worldwide. Combination of hyperthermia and chemotherapy has shown promising results in several abdominal tumours, but high expression of HSP90 in tumours attenuated the efficacy of hyperthermia. Thus a combination of hyperthermia and inhibition of HSP90 might be a feasible therapeutic strategy for HCC. One hepatic cell line (L02) and two HCC cell lines (Huh7 and HepG2) were heated at 42 °C for 0, 0.5 or 4 h with or without 100 nM 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG). HCC cells of the combination group exhibited more G2/M arrest and higher apoptotic rates which might result from suffering from more reactive oxygen species and serious DNA damage. Heat shock/17-DMAG co-treatment of HCC cells also destabilized CDK1, Cyclin B1 and CDC25C with a concomitant decreased proportion of cells in the M phase. Furthermore, co-treatment impaired the interaction of HSP90α with CDC37 and with CDK1, accompanied with decreased soluble CDK1. Combination of 17-DMAG with a 1.5-h whole body hyperthermia treatment attenuated tumour growth in xenograft mice models. These results suggest hyperthermia sensitize HCC to 17-DMAG, and combination of hyperthermia with 17-DMAG might be a potential therapeutic strategy for HCC.
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Anti-infective Activity of 2-Cyano-3-Acrylamide Inhibitors with Improved Drug-Like Properties against Two Intracellular Pathogens. Antimicrob Agents Chemother 2016; 60:4183-96. [PMID: 27139470 DOI: 10.1128/aac.03021-15] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 04/24/2016] [Indexed: 12/17/2022] Open
Abstract
Due to the rise of antibiotic resistance and the small number of effective antiviral drugs, new approaches for treating infectious diseases are urgently needed. Identifying targets for host-based therapies represents an emerging strategy for drug discovery. The ubiquitin-proteasome system is a central mode of signaling in the eukaryotic cell and may be a promising target for therapies that bolster the host's ability to control infection. Deubiquitinase (DUB) enzymes are key regulators of the host inflammatory response, and we previously demonstrated that a selective DUB inhibitor and its derivative promote anti-infective activities in host cells. To find compounds with anti-infective efficacy but improved toxicity profiles, we tested a library of predominantly 2-cyano-3-acrylamide small-molecule DUB inhibitors for anti-infective activity in macrophages against two intracellular pathogens: murine norovirus (MNV) and Listeria monocytogenes We identified compound C6, which inhibited DUB activity in human and murine cells and reduced intracellular replication of both pathogens with minimal toxicity in cell culture. Treatment with C6 did not significantly affect the ability of macrophages to internalize virus, suggesting that the anti-infective activity interferes with postentry stages of the MNV life cycle. Metabolic stability and pharmacokinetic assays showed that C6 has a half-life in mouse liver microsomes of ∼20 min and has a half-life of approximately 4 h in mice when administered intravenously. Our results provide a framework for targeting the host ubiquitin system in the development of host-based therapies for infectious disease. Compound C6 represents a promising tool with which to elucidate the role of DUBs in the macrophage response to infection.
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Hartman JH, Martin HC, Caro AA, Pearce AR, Miller GP. Subcellular localization of rat CYP2E1 impacts metabolic efficiency toward common substrates. Toxicology 2015; 338:47-58. [PMID: 26463279 DOI: 10.1016/j.tox.2015.10.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 09/22/2015] [Accepted: 10/06/2015] [Indexed: 01/12/2023]
Abstract
Cytochrome P450 2E1 (CYP2E1) detoxifies or bioactivates many low molecular-weight compounds. Most knowledge about CYP2E1 activity relies on studies of the enzyme localized to endoplasmic reticulum (erCYP2E1); however, CYP2E1 undergoes transport to mitochondria (mtCYP2E1) and becomes metabolically active. We report the first comparison of in vitro steady-state kinetic profiles for erCYP2E1 and mtCYP2E1 oxidation of probe substrate 4-nitrophenol and pollutants styrene and aniline using subcellular fractions from rat liver. For all substrates, metabolic efficiency changed with substrate concentration for erCYP2E1 reflected in non-hyperbolic kinetic profiles but not for mtCYP2E1. Hyperbolic kinetic profiles for the mitochondrial enzyme were consistent with Michaelis-Menten mechanism in which metabolic efficiency was constant. By contrast, erCYP2E1 metabolism of 4-nitrophenol led to a loss of enzyme efficiency at high substrate concentrations when substrate inhibited the reaction. Similarly, aniline metabolism by erCYP2E1 demonstrated negative cooperativity as metabolic efficiency decreased with increasing substrate concentration. The opposite was observed for erCYP2E1 oxidation of styrene; the sigmoidal kinetic profile indicated increased efficiency at higher substrate concentrations. These mechanisms and CYP2E1 levels in mitochondria and endoplasmic reticulum were used to estimate the impact of CYP2E1 subcellular localization on metabolic flux of pollutants. Those models showed that erCYP2E1 mainly carries out aniline metabolism at all aniline concentrations. Conversely, mtCYP2E1 dominates styrene oxidation at low styrene concentrations and erCYP2E1 at higher concentrations. Taken together, subcellular localization of CYP2E1 results in distinctly different enzyme activities that could impact overall metabolic clearance and/or activation of substrates and thus impact the interpretation and prediction of toxicological outcomes.
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Affiliation(s)
- Jessica H Hartman
- Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - H Cass Martin
- Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR, United States; Department of Chemistry, University of Central Arkansas, Conway, AR, United States
| | - Andres A Caro
- Department of Chemistry, Hendrix College, Conway, AR, United States
| | - Amy R Pearce
- Arkansas Biosciences Institute, United States; Psychology & Counseling, Arkansas State University, Jonesboro, AR, United States
| | - Grover P Miller
- Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR, United States.
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Lyu C, Zhou W, Zhang Y, Zhang S, Kou F, Wei H, Zhang N, Zuo Z. Identification and characterization of in vitro and in vivo metabolites of steroidal alkaloid veratramine. Biopharm Drug Dispos 2015; 36:308-24. [PMID: 25765359 DOI: 10.1002/bdd.1942] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2014] [Revised: 02/11/2015] [Accepted: 02/25/2015] [Indexed: 12/22/2022]
Abstract
Veratramine, a steroidal alkaloid originating from Veratrum nigrum L., has demonstrated distinct anti-tumor and anti-hypertension effects, however, its metabolism has rarely been explored. The objective of the current study was to provide a comprehensive investigation of its metabolic pathways. The in vitro metabolic profiles of veratramine were evaluated by incubating it with liver microsomes and cytosols. The in vivo metabolic profiles in plasma, bile, urine and feces were monitored by UPLC-MS/MS after oral (20 mg/kg) and i.v. (50 µg/kg) administration in rats. Meanwhile, related P450s inhibitors and recombinant P450s and SULTs were used to identify the isozymes responsible for its metabolism. Eleven metabolites of veratramine, including seven hydroxylated, two sulfated and two glucuronidated metabolites, were characterized. Unlike most alkaloids, the major reactive sites of veratramine were on ring A and B instead of on the amine moiety. CYP2D6 was the major isozyme mediating hydroxylation, and substrate inhibition was observed with a Vmax , Ki and Clint of 2.05 ± 0.53 nmol/min/mg, 33.08 ± 10.13 µ m and 13.58 ± 1.27 µL/min/mg. SULT2A1, with Km , Vmax and Clint values of 19.37 ± 0.87 µ m, 1.51 ± 0.02 nmol/min/mg and 78.19 ± 8.57 µL/min/mg, was identified as the major isozyme contributing to its sulfation. In conclusion, CYP2D6 and SULT2A1 mediating hydroxylation and sulfation were identified as the major biotransformation for veratramine.
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Affiliation(s)
- Chunming Lyu
- Technology Laboratory Center, Shanghai University of Traditional Chinese Medicine, Shanghai, PR China.,School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR
| | - Wenbin Zhou
- Center for Chinese Medical Therapy and Systems Biology, Shanghai University of Traditional Chinese Medicine, Shanghai, PR China
| | - Yufeng Zhang
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR
| | - Shen Zhang
- Department of Rehabilitation, Changzheng Hospital Affiliated to Second Military Medicine University, Shanghai, 200003, PR China
| | - Fang Kou
- Center for Chinese Medical Therapy and Systems Biology, Shanghai University of Traditional Chinese Medicine, Shanghai, PR China
| | - Hai Wei
- Center for Chinese Medical Therapy and Systems Biology, Shanghai University of Traditional Chinese Medicine, Shanghai, PR China
| | - Ning Zhang
- Technology Laboratory Center, Shanghai University of Traditional Chinese Medicine, Shanghai, PR China
| | - Zhong Zuo
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR
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Ambade A, Catalano D, Lim A, Kopoyan A, Shaffer SA, Mandrekar P. Inhibition of heat shock protein 90 alleviates steatosis and macrophage activation in murine alcoholic liver injury. J Hepatol 2014; 61:903-11. [PMID: 24859453 PMCID: PMC4169725 DOI: 10.1016/j.jhep.2014.05.024] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Revised: 03/28/2014] [Accepted: 05/12/2014] [Indexed: 12/17/2022]
Abstract
BACKGROUND & AIMS Heat shock protein 90 (hsp90) is an emerging therapeutic target in chronic liver diseases. Hsp90 plays an important role in liver immune cell activation; however its role in alcoholic liver disease (ALD) remains elusive. Here we hypothesize that hsp90 is crucial in alcohol induced steatosis and pro-inflammatory cytokine production. To test this hypothesis, we employed a pharmacological inhibitor of hsp90, 17-DMAG (17-Dimethylamino-ethylamino-17-demethoxygeldanamycin) in an in vivo mouse model of acute and chronic alcoholic liver injury. METHODS C57BL/6 mice were given either a single dose of ethanol via oral gavage (acute) or chronically fed alcohol for 2 weeks followed by oral gavage (chronic-binge). 17-DMAG was administered during or at the end of feeding. Liver injury parameters, inflammatory cytokines and lipid metabolism genes were analysed. RESULTS Our results reveal increased expression of hsp90 in human and mouse alcoholic livers. In vivo inhibition of hsp90, using 17-DMAG, not only prevented but also alleviated alcoholic liver injury, determined by lower serum ALT, AST and reduced hepatic triglycerides. Mechanistic analysis showed that 17-DMAG decreased alcohol mediated oxidative stress, reduced serum endotoxin, decreased inflammatory cells, and diminished sensitization of liver macrophages to LPS, resulting in downregulation of CD14, NFκB inhibition, and decreased pro-inflammatory cytokine production. Hsp90 inhibition decreased fatty acid synthesis genes via reduced nuclear SREBP-1 and favoured fatty acid oxidation genes via PPARα. CONCLUSIONS Inhibition of hsp90 decreased alcohol induced steatosis and pro-inflammatory cytokines and inhibited alcoholic liver injury. Hsp90 is therefore relevant in human alcoholic cirrhosis and a promising therapeutic target in ALD.
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Affiliation(s)
- Aditya Ambade
- Department of Medicine, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, United States
| | - Donna Catalano
- Department of Medicine, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, United States
| | - Arlene Lim
- Department of Medicine, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, United States
| | - Andre Kopoyan
- Proteomics and Mass Spectrometry Facility, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, United States
| | - Scott A Shaffer
- Proteomics and Mass Spectrometry Facility, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, United States
| | - Pranoti Mandrekar
- Department of Medicine, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, United States.
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Hu ZY, Lu J, Zhao Y. A physiologically based pharmacokinetic model of alvespimycin in mice and extrapolation to rats and humans. Br J Pharmacol 2014; 171:2778-89. [PMID: 24471734 PMCID: PMC4243854 DOI: 10.1111/bph.12609] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Revised: 11/10/2013] [Accepted: 01/09/2014] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND AND PURPOSE Alvespimycin, a new generation of heat shock protein 90 (Hsp90) inhibitor in clinical trial, is a promising therapeutic agent for cancer. Pharmacokinetic models of alvespimycin would help in the understanding of drug disposition, predicting drug exposure and interpreting dose-response relationship. In the present study we aimed to develop a physiologically based pharmacokinetic (PBPK) model of alvespimycin in mice and evaluate the utility of the model for predicting alvespimycin disposition in other species. EXPERIMENTAL APPROACH A literature search was performed to collect pharmacokinetic data for alvespimycin. A PBPK model was initially constructed to demonstrate the disposition of alvespimycin in mice, and then extrapolated to rats and humans by taking into account the interspecies differences in physiological- and chemical-specific parameters. KEY RESULTS A PBPK model, employing a permeability-limited model structure and saturable tissue binding, was built in mice. It successfully characterized the time course of the disposition of alvespimycin in mice. After extrapolation to rats, the model simulated the alvespimycin concentration-time profiles in rat tissues with acceptable accuracies. Likewise, a reasonable match was found between the observed and simulated human plasma pharmacokinetics of alvespimycin. CONCLUSIONS AND IMPLICATIONS The PBPK model described here is beneficial to the understanding and prediction of the effects of alvespimycin in different species. It also provides a good basis for further development, which necessitates additional studies, especially those needed to clarify the in-depth mechanism of alvespimycin elimination. A refined PBPK model would benefit the understanding of dose-response relationships and optimization of dosing regimens.
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Affiliation(s)
- Zhe-Yi Hu
- Department of Clinical Pharmacy, College of Pharmacy, University of Tennessee Health Science CenterMemphis, TN, USA
| | - Jingtao Lu
- The Hamner Institutes for Health SciencesResearch Triangle Park, NC, USA
| | - Yuansheng Zhao
- The Hamner Institutes for Health SciencesResearch Triangle Park, NC, USA
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Qu Z, Wang S, Teng R, Yi X. PU-H71 effectively induces degradation of IκB kinase β in the presence of TNF-α. Mol Cell Biochem 2013; 386:135-42. [PMID: 24114662 DOI: 10.1007/s11010-013-1852-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 09/27/2013] [Indexed: 12/29/2022]
Abstract
This study is to determine if PU-H71, a heat shock protein inhibitor, induces killing of malignant breast cells together with treatment of tumor necrosis factor-α (TNF-α). The related molecular mechanisms were also studied. A primary mammary epithelial cell line HMEC2595 cells and the highly metastatic breast cell line MDA-MB-231, the HER2-positive BT-474 cells, and the ER-positive MCF7 cells were treated with PU-H71 in the presence or absence of TNF-α. The effects of PU-H71 and TNF-α treatments on cells viabilities and on intracellular signaling pathway proteins were determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, apoptosis assays, immunoblot assays, and luciferase assays. It was found that TNF-α enhances the toxic effects of PU-H71 on tumor cells but not normal cells. PU-H71 treatments lead to degradation of IKKβ. Moreover, PU-H71 down-regulates the NF-κB transcriptional activity induced by TNF-α treatment. The experimental results indicated PU-H71 effectively induces cell killing of malignant breast cells in the presence of TNF-α, possibly through a mechanism related to degradation of IKKβ. It is suggested that combination of PU-H71 and TNF-α treatments might be an effective therapeutic strategy of breast malignancies.
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Affiliation(s)
- Zhuling Qu
- The Affiliated Hospital of Medical College, Qingdao University, Qingdao, 266021, Shandong Province, China,
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Tang C, Tang C, Zhan W, Du J, Wang Z, Peng X. Strategies for ascertaining the interference of phase II metabolites co-eluting with parent compounds using LC-MS/MS. J Sep Sci 2013; 36:2584-92. [PMID: 23868670 DOI: 10.1002/jssc.201300235] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 05/05/2013] [Accepted: 05/29/2013] [Indexed: 11/10/2022]
Abstract
LC-MS/MS is currently the most selective and efficient tool for the quantitative analysis of drugs and metabolites in the pharmaceutical industry and in clinical assays. However, phase II metabolites sometimes negatively affect the selectivity and efficiency of the LC-MS/MS method, especially for the metabolites that possess similar physicochemical characteristics and generate the same precursor ions as their parent compounds due to the in-source collision-induced dissociation during the ionization process. This paper proposes some strategies for examining co-eluting metabolites existing in real samples, and further assuring whether these metabolites could affect the selectivity and accuracy of the analytical methods. Strategies using precursor-ion scans and product-ion scans were applied in this study. An example drug, namely, caffeic acid phenethyl ester, which can generate many endogenous phase II metabolites, was selected to conduct this work. These metabolites, generated during the in vivo metabolic processes, can be in-source-dissociated to the precursor ions of their parent compounds. If these metabolites are not separated from their parent compounds, the quantification of the target analytes (parent compounds) would be influenced. Some metabolites were eluted closely to caffeic acid phenethyl ester on LC columns, although long columns and relatively long elution programs were used. The strategies can be utilized in quantitative methodologies that apply LC-MS/MS to assure the performance of selectivity, thus enhancing the reliability of the experimental data.
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Affiliation(s)
- Caiming Tang
- State key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, PR China.
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Qu Z, Dong H, Xu X, Feng W, Yi X. Combined effects of 17-DMAG and TNF on cells through a mechanism related to the NF-kappaB pathway. Diagn Pathol 2013; 8:70. [PMID: 23635099 PMCID: PMC3716826 DOI: 10.1186/1746-1596-8-70] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Accepted: 04/22/2013] [Indexed: 02/04/2023] Open
Abstract
Objective The tumor necrosis factor (TNF) and the cellular NF-κB pathway protein IKKβ play important roles in various cellular processes such as cell proliferation, survival, differentiation, and apoptosis. A heat shock protein 90 inhibitor, 17-DMAG, can induce apoptosis of some tumor cells. This study is to determine the combined effects of 17-DMAG and TNF on malignant cells and the related mechanisms. Methods We have determined effects of 17-DMAG, an Hsp90 inhibitor, and TNF treatments on the small cell lung cancer cell line (MS-1), the adenocarcinoma cell line (A549), the squamous-cell carcinoma cell line (LK-2), and the normal human bronchial epithelium cell line (NuLi-1) by using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrozolium bromide assay. To determine if 17-DMAG inhibit the expression of IKKβ in the normal human NuLi-1 cells, and the malignant MS-1, A549, and LK-2 cells, immunoblotting assays and luciferase assays were performed. Results It was found that the combined treatments resulted in synergistic killing of malignant cells, which was confirmed by the apoptosis determination using a fluorescence microscopic assay following staining of the drug-treated cells with Hoescht 33258. The immunoblotting results indicated that the synergistic killing due to 17-DMAG and TNF treatments may be related to the decreases in IKKβ levels in the presence of 17-DMAG. Conclusions The results suggest that combination of 17-DMAG and TNF treatments might be useful for treating malignancies upon further study in the further. Virtual slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2041198513886824
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Affiliation(s)
- Zhuling Qu
- Affiliated Hospital of Medical College, Qingdao University, Qingdao, Shandong province 266021, China.
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