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Ogbodu RO, Nitzsche B, Ma A, Atilla D, Gürek AG, Höpfner M. Photodynamic therapy of hepatocellular carcinoma using tetra-triethyleneoxysulfonyl zinc phthalocyanine as photosensitizer. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2020; 208:111915. [DOI: 10.1016/j.jphotobiol.2020.111915] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 04/15/2020] [Accepted: 05/19/2020] [Indexed: 02/07/2023]
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Dong Z, Wang J, Zhang H, Zhan T, Chen Y, Xu S. Identification of potential key genes in esophageal adenocarcinoma using bioinformatics. Exp Ther Med 2019; 18:3291-3298. [PMID: 31616504 PMCID: PMC6781836 DOI: 10.3892/etm.2019.7973] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Accepted: 11/07/2018] [Indexed: 12/29/2022] Open
Abstract
Esophageal adenocarcinoma (EAC) is the predominant pathological subtype of esophageal cancer in Europe and the USA. The present bioinformatics study analyzed a high-throughput sequencing dataset, GSE94869, to determine differentially expressed genes (DEGs) in order to identify key genes, biological processes and pathways associated with EAC. Functional enrichment analysis was performed using the Database for Annotation Visualization and Integrated Discovery. The co-expression network of the DEGs was established using Weighted Gene Co-Expression Network Analysis and visualized using Cytoscape. A Kaplan-Meier analysis based on The Cancer Genome Atlas (TCGA) database was used to identify prognosis-associated genes. Univariate and multivariate Cox proportional hazard models were used to identify genes with a prognostic value regarding relapse-free survival (RFS), while validation of the differential expression of prognosis-associated genes was performed using a box plot based on data from TCGA and another microarray dataset, GSE26886. A total of 130 DEGs, comprising 82 upregulated and 48 downregulated genes, were identified. The upregulated DEGs were significantly associated with extracellular matrix organization, disassembly, and the phosphoinositide-3 kinase/AKT, Rap1 and Ras signaling pathways, while the downregulated genes were associated with the Wnt signalling pathway. Subsequently, two co-expression modules were established and 20 hub genes were identified. The blue module was associated with the Rap1 signaling pathway, while the turquoise module was associated with the Ras and Rap1 signaling pathways. Among them, methyltransferase like 7B (METTL7B) was associated with RFS. Furthermore, the overexpression of METTL7B in EAC was successfully validated using data from TCGA and GSE26886. The present study identified key genes and provides potential biomarkers for the diagnosis and treatment of EAC.
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Affiliation(s)
- Zhiyu Dong
- Department of Gastroenterology, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, P.R. China
| | - Junwen Wang
- Department of Gastroenterology, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, P.R. China
| | - Haiqin Zhang
- Department of Gastroenterology, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, P.R. China
| | - Tingting Zhan
- Department of Gastroenterology, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, P.R. China
| | - Ying Chen
- Department of Gastroenterology, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, P.R. China
| | - Shuchang Xu
- Department of Gastroenterology, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, P.R. China
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Chen YF, Xie JD, Jiang YC, Chen DT, Pan JH, Chen YH, Yuan YF, Wen ZS, Zeng WA. The Prognostic Value of Peripheral Benzodiazepine Receptor in Patients with Esophageal Squamous Cell Carcinoma. J Cancer 2017; 8:3343-3355. [PMID: 29158807 PMCID: PMC5665051 DOI: 10.7150/jca.20739] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 08/06/2017] [Indexed: 01/06/2023] Open
Abstract
Background: The peripheral benzodiazepine receptor (PBR) has previously been reported as an oncogene in prostate, breast and colorectal cancers, but its prognostic value, biological behavior and function in esophageal squamous cell carcinoma (ESCC) has not been investigated. Methods: qRT-PCR, western blotting and immunohistochemistry (IHC) were used to detect PBR expression in ESCC and matched non-cancerous tissues. Based on all of the significantly independent factors, a nomogram was established to predict the prognosis of ESCC patients. In addition, we performed comprehensive in vitro experiments to study the functions of PBR in cell growth, colony formation, and migration ability, as well as its relationship with epithelial-mesenchymal transition (EMT) related proteins in ESCC cells. Results: The mRNA and protein expression levels of PBR in ESCC were higher than those in adjacent non-tumor esophageal epithelial tissues. The IHC results demonstrated that PBR expression was an independent prognostic factor in ESCC survival, patients with higher PBR expression had a poorer survival than those with low expression, and PBR expression was significantly associated with lymphoid nodal status. Furthermore, a nomogram was established to reliably predict the probability of death in ESCC patients, with a Harrell's c-index of 0.696. In the vitro experiments, knocking down the expression of PBR inhibited proliferation, colony formation and migration of ESCC cells, and regulated EMT-associated proteins (up-regulation of E-cadherin, ZO-1 and β-catenin and concomitant with down-regulation of Fibronectin and N-cadherin). Conclusions: PBR is an independent prognostic factor in ESCC, and it promotes ESCC progression and metastasis. Basing on PBR expression level, a nomogram is established and performs a well in predicting survival of ESCC patients.
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Affiliation(s)
- You-Fang Chen
- Department of Anesthesiology, Cancer Center, Sun Yat-Sen University, State Key Laboratory of Oncology in South China, Guangzhou510060, Guangdong, China
| | - Jing-Dun Xie
- Department of Anesthesiology, Cancer Center, Sun Yat-Sen University, State Key Laboratory of Oncology in South China, Guangzhou510060, Guangdong, China
| | - Yu-Chuan Jiang
- Department of Thoracic Oncology, Cancer Center, Sun Yat-Sen University, State Key Laboratory of Oncology in South China, Guangzhou510060, Guangdong, China
| | - Dong-Tai Chen
- Department of Anesthesiology, Cancer Center, Sun Yat-Sen University, State Key Laboratory of Oncology in South China, Guangzhou510060, Guangdong, China
| | - Jia-Hao Pan
- Department of Anesthesiology, Cancer Center, Sun Yat-Sen University, State Key Laboratory of Oncology in South China, Guangzhou510060, Guangdong, China
| | - Yong-Hua Chen
- Department of Anesthesiology, Cancer Center, Sun Yat-Sen University, State Key Laboratory of Oncology in South China, Guangzhou510060, Guangdong, China
| | - Yun-Fei Yuan
- Department of Hepatobiliary Oncology, Cancer Center, Sun Yat-Sen University, State Key Laboratory of Oncology in South China, Guangzhou510060, Guangdong, China
| | - Zhe-Sheng Wen
- Department of Thoracic Oncology, Cancer Center, Sun Yat-Sen University, State Key Laboratory of Oncology in South China, Guangzhou510060, Guangdong, China
| | - Wei-An Zeng
- Department of Anesthesiology, Cancer Center, Sun Yat-Sen University, State Key Laboratory of Oncology in South China, Guangzhou510060, Guangdong, China
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TSPO ligand residence time influences human glioblastoma multiforme cell death/life balance. Apoptosis 2015; 20:383-98. [PMID: 25413799 DOI: 10.1007/s10495-014-1063-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Ligands addressed to the mitochondrial Translocator Protein (TSPO) have been suggested as cell death/life and steroidogenesis modulators. Thus, TSPO ligands have been proposed as drug candidates in several diseases; nevertheless, a correlation between their binding affinity and in vitro efficacy has not been demonstrated yet, questioning the specificity of the observed effects. Since drug-target residence time is an emerging parameter able to influence drug pharmacological features, herein, the interaction between TSPO and irDE-MPIGA, a covalent TSPO ligand, was investigated in order to explore TSPO control on death/life processes in a standardized glioblastoma cell setting. After 90 min irDE-MPIGA cell treatment, 25 nM ligand concentration saturated irreversibly all TSPO binding sites; after 24 h, TSPO de-novo synthesis occurred and about 40 % TSPO binding sites resulted covalently bound to irDE-MPIGA. During cell culture treatments, several dynamic events were observed: (a) early apoptotic markers appeared, such as mitochondrial membrane potential collapse (at 3 h) and externalization of phosphatidylserine (at 6 h); (b) cell viability was reduced (at 6 h), without cell cycle arrest. After digitonin-permeabilized cell suspension treatment, a modulation of mitochondrial permeability transition pore was evidenced. Similar effects were elicited by the reversible TSPO ligand PIGA only when applied at micromolar dose. Interestingly, after 6 h, irDE-MPIGA cell exposure restored cell survival parameters. These results highlighted the ligand-target residence time and the cellular setting are crucial parameters that should be taken into account to understand the drug binding affinity and efficacy correlation and, above all, to translate efficiently cellular drug responses from bench to bedside.
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Han F, Huo Y, Huang CJ, Chen CL, Ye J. MicroRNA-30b promotes axon outgrowth of retinal ganglion cells by inhibiting Semaphorin3A expression. Brain Res 2015; 1611:65-73. [PMID: 25791621 DOI: 10.1016/j.brainres.2015.03.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 02/08/2015] [Accepted: 03/06/2015] [Indexed: 10/23/2022]
Abstract
Semaphorin3A (Sema3A) is a major inhibitory factor of optic nerve (ON) regeneration post-injury. Many microRNAs (miRNAs) are expressed specifically in the mammalian brain and retina and are dynamically regulated during development, suggesting that this group of miRNAs may be associated with neural development. We found that microRNA-30b (miR-30b) bound to the three prime untranslated region (3' UTR) of Sema3A and inhibited the expression of Sema3A mRNA. The mRNA expression level of miR-30b and the protein expression levels of Sema3A, Neuropilin1 (NRP1), PlexinA1 (PlexA1), phosphorylated p38MAPK (p-p38MAPK), and active caspase-3 were all upregulated in retinas from rats with a damaged ON relative to those with an intact ON. Transfection of cultured retinal ganglion cells (RGCs) with an miR-30b mimic led to decreased levels of Sema3A, NRP1, PlexA1, p-p38MAPK, and active caspase-3 protein expression, as well as axon elongation and reduced levels of apoptosis. These findings provide evidence that miR-30b inhibits Sema3A expression. Decreased Sema3A expression promotes axon outgrowth in RGCs due to reduced levels of Sema3A binding to NRP1 and PlexA1 and simultaneously reduces apoptosis by inhibiting the p38MAPK and caspase-3 pathways. Our findings provide the first evidence that miR-30b-mediated Sema3A downregulation may serve as a new strategy for the clinical treatment of ON injury.
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Affiliation(s)
- F Han
- Department of Ophthalmology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China
| | - Y Huo
- Department of Ophthalmology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China
| | - C-J Huang
- Department of Ophthalmology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China
| | - C-L Chen
- Department of Ophthalmology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China
| | - J Ye
- Department of Ophthalmology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, China.
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Krishnaraj C, Muthukumaran P, Ramachandran R, Balakumaran MD, Kalaichelvan PT. Acalypha indica Linn: Biogenic synthesis of silver and gold nanoparticles and their cytotoxic effects against MDA-MB-231, human breast cancer cells. ACTA ACUST UNITED AC 2014. [PMID: 28626661 PMCID: PMC5466127 DOI: 10.1016/j.btre.2014.08.002] [Citation(s) in RCA: 144] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This study reports the in vitro cytotoxic effect of biologically synthesized silver and gold nanoparticles against MDA-MB-231, human breast cancer cells. Formation of silver and gold nanoparticles was observed within 30 min and the various characterization techniques such as UV–vis spectrophotometer, FE-SEM, TEM and XRD studies were confirmed the synthesis of nanoparticles. Further, MTT, acridine orange and ethidium bromide (AO/EB) dual staining, caspase-3 and DNA fragmentation assays were carried out using various concentrations of silver and gold nanoparticles ranging from 1 to 100 μg/ml. At 100 μg/ml concentration, the plant extract derived nanoparticles exhibited significant cytotoxic effects and the apoptotic features were confirmed through caspase-3 activation and DNA fragmentation assays. Thus, the results of the present study indicate that biologically synthesized silver and gold nanoparticles might be used to treat breast cancer; however, it necessitates clinical studies to ascertain their potential as anticancer agents.
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Affiliation(s)
- C Krishnaraj
- Centre for Advanced Studies in Botany, University of Madras, Guindy Campus, Chennai 600 025, Tamil Nadu, India
| | - P Muthukumaran
- Centre for Biotechnology, Anna University, Guindy, Chennai 600 025, Tamil Nadu, India
| | - R Ramachandran
- Centre for Advanced Studies in Botany, University of Madras, Guindy Campus, Chennai 600 025, Tamil Nadu, India
| | - M D Balakumaran
- Centre for Advanced Studies in Botany, University of Madras, Guindy Campus, Chennai 600 025, Tamil Nadu, India
| | - P T Kalaichelvan
- Centre for Advanced Studies in Botany, University of Madras, Guindy Campus, Chennai 600 025, Tamil Nadu, India
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Rosenberg N, Rosenberg O, Weizman A, Veenman L, Gavish M. In vitro effect of FGIN-1-27, a ligand to 18 kDa mitochondrial translocator protein, in human osteoblast-like cells. J Bioenerg Biomembr 2014; 46:197-204. [DOI: 10.1007/s10863-014-9542-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 01/29/2014] [Indexed: 12/01/2022]
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Mendonça-Torres MC, Roberts SS. The translocator protein (TSPO) ligand PK11195 induces apoptosis and cell cycle arrest and sensitizes to chemotherapy treatment in pre- and post-relapse neuroblastoma cell lines. Cancer Biol Ther 2013; 14:319-26. [PMID: 23358477 DOI: 10.4161/cbt.23613] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
High-risk neuroblastoma (NB) has a poor prognosis. Even with intensive myeloablative chemotherapy, relapse is common and almost uniformly fatal, and new treatments are needed. Translocator protein 18kDa (TSPO) ligands have been studied as potential new therapeutic agents in many cancers, but not in NB. We studied the effects of TSPO ligands on cell proliferation, cell cycle progression and apoptosis using paired cell lines derived from the same patient at the time of initial surgery and again after development of progressive disease or relapse post-chemotherapy. We found that TSPO expression was significantly increased 2- to 10-fold in post-relapse cell lines compared with pre-treatment lines derived from the same individual. Subsequently, these cell lines were treated with the specific TSPO ligand 1-(2-chlorophenyl-N-methylpropyl)-3-isoquinolinecarboxamide (PK11195) (0-160µM) as a single agent, with cytotoxic chemotherapy agents alone (carboplatin, etoposide or melphalan), or with combinations of PK11195 and chemotherapy drugs. We found that PK11195 inhibited proliferation in a dose-dependent manner, induced apoptosis and caused G 1/S cell cycle arrest in all tested NB cell lines at micromolar concentrations. In addition, PK11195 significantly decreased mRNA expression of the chemotherapy resistance efflux pumps ABCA3, ABCB1 and ABCC1 in two post-relapse NB cell lines. We also found that pre-treatment with PK11195 sensitized these cell lines to treatment with cytotoxic chemotherapy agents. These results suggest that PK11195 alone or in combination with standard chemotherapeutic drugs warrants further study for the treatment of neuroblastoma.
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Affiliation(s)
- Maria C Mendonça-Torres
- Department of Pediatrics, Division of Hematology/Oncology, Uniformed Services University of the Health Sciences, Bethesda, MD USA
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9
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Alexandre L, Broughton T, Loke Y, Beales ILP. Meta-analysis: risk of esophageal adenocarcinoma with medications which relax the lower esophageal sphincter. Dis Esophagus 2012; 25:535-44. [PMID: 22129441 DOI: 10.1111/j.1442-2050.2011.01285.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Reasons for the rising annual incidence of esophageal adenocarcinoma (EAC) remain uncertain. Previous studies have given conflicting results, but some have suggested that drugs which relax the lower esophageal sphincter (LES) may increase the risk of EAC. This study is to determine systematically the risk of EAC associated with individual medications which relax the LES and compare risks with esophageal squamous cell carcinoma (ESCC) and gastric cardia adenocarcinoma (GCA). Relevant published studies were identified by systematic searching PubMed for case-control studies reporting on risk of EAC, ESCC or GCA with use of medications known to reduce LES pressure. Pooled odds ratios (ORs) were calculated for each malignancy. Data were analyzed from four case-control studies involving 9,412 participants. EAC was significantly associated with theophylline use (OR 1.55, 95% confidence interval [CI] 1.05-2.28; P= 0.03, I(2) = 0%) and anticholinergic medications (OR 1.66, 95% CI 1.13-2.44; P= 0.01, I(2) = 84%). This effect was not observed in cases of ESCC or GCA. Other drug groups including calcium channel modulators and nitrates did not increase the risk of EAC. An inverse relationship was observed between ESCC and nitrates and between GCA and benzodiazepines. The lack of increased EAC risk with many commonly used medications is reassuring. However, a significant correlation was found between EAC and the use of anticholinergics and theophyllines. This may reflect common causality between obstructive lung disease and EAC, and further studies to explore these relationships are warranted.
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Affiliation(s)
- L Alexandre
- Department of Gastroenterology, Norfolk and Norwich University Hospital, Norwich, UK
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10
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Denora N, Laquintana V, Trapani A, Lopedota A, Latrofa A, Gallo JM, Trapani G. Translocator protein (TSPO) ligand-Ara-C (cytarabine) conjugates as a strategy to deliver antineoplastic drugs and to enhance drug clinical potential. Mol Pharm 2010; 7:2255-69. [PMID: 20958082 DOI: 10.1021/mp100235w] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The aim of this work was to evaluate TSPO ligand-Ara-C conjugation as an approach for the selective delivery of the antineoplastic agent to brain tumors as well as for overcome P-gp resistance induction observed for the majority of cytotoxic agents, enhancing the drug clinical potential. To this end, the novel N-imidazopyridinacetyl-Ara-C conjugates 3a-c, 10 and 15 have been prepared and evaluated for their cytotoxicity against glioma cell lines. In contrast to that observed for 3a-c and 10, the conjugate 15 resulted stable in both phosphate buffer and physiological medium. In all cases, the release of free Ara-C from hydrolyzed conjugates was checked by HPLC and ESI-MS analysis. Conjugates 10 and 15 displayed very high in vitro TSPO affinity and selectivity, and, hence, they may possess potential for targeted brain delivery. Due to the favorable features displayed by the conjugate 15, it was further evaluated on glioma cell lines, expressing high levels of TSPO, in the presence and in the absence of specific nucleoside transport (NT) inhibitors. In contrast to that observed for the free Ara-C, the presence of NT inhibitors did not reduce the cytotoxic activity of 15. Moreover, conjugate 15, as N(4)-acyl derivative of Ara-C, should be resistant to inactivation by cytidine deaminase, and it may possess enhanced propensity to target brain tumor cells characterized by a reduced expression of NTs. In addition, this conjugate behaves as a clear P-gp modulator and thereby may be useful to reverse MDR. Transport studies across the MDCKII-MDR1 monolayer indicated that conjugate 15 should overcome the BBB by transcellular pathway. All these features may be useful for enhancing the clinical potential of the nucleoside drug Ara-C.
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Affiliation(s)
- Nunzio Denora
- Dipartimento Farmaco-Chimico, Facoltà di Farmacia, Università degli Studi di Bari, Via Orabona 4, 70125 Bari, Italy
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Sathya S, Sudhagar S, Vidhya Priya M, Bharathi Raja R, Muthusamy VS, Niranjali Devaraj S, Lakshmi BS. 3β-hydroxylup-20(29)-ene-27,28-dioic acid dimethyl ester, a novel natural product from Plumbago zeylanica inhibits the proliferation and migration of MDA-MB-231 cells. Chem Biol Interact 2010; 188:412-20. [PMID: 20670616 DOI: 10.1016/j.cbi.2010.07.019] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2010] [Revised: 07/20/2010] [Accepted: 07/20/2010] [Indexed: 10/19/2022]
Abstract
Plumbago zeylanica, a traditional Indian herb is being used for the therapy of rheumatism and has been approved for anti-tumor activity. However, the molecular mechanisms involved in the biological action are not very well understood. In this study, the anti-invasive activities of P. zeylanica methanolic extract (PME) and pure compound 3β-hydroxylup-20(29)-ene-27,28-dioic acid (PZP) isolated from it are investigated in vitro. PME and PZP were noted to have the ability to induce apoptosis as assessed by flow cytometry. Further, the molecular mechanism of apoptosis induced by PME and PZP was found by the loss of mitochondrial membrane potential with the down regulation of Bcl-2, increased expression of Bad, release of cytochrome c, activation of caspase-3 and cleavage of PARP leading to DNA fragmentation. Importantly, both PME and PZP were observed to suppress MDA-MB-231 cells adhesion to the fibronectin-coated substrate and also inhibited the wound healing migration and invasion of MDA-MB-231 cells through the reconstituted extracellular matrix. Gelatin zymography revealed that PME and PZP decreased the secretion of matrix metalloproteinases-2 (MMP-2) and metalloproteinases-9 (MMP-9). Interestingly both PME and PZP exerted an inhibitory effect on the protein levels of p-PI3K, p-Akt, p-JNK, p-ERK1/2, MMP-2, MMP-9, VEGF and HIF-1α that are consistent with the observed anti-metastatic effect. Collectively, these data provide the molecular basis of the anti-proliferative and anti-metastatic effects of PME and PZP.
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Laquintana V, Denora N, Musacchio T, Lasorsa M, Latrofa A, Trapani G. Peripheral benzodiazepine receptor ligand-PLGA polymer conjugates potentially useful as delivery systems of apoptotic agents. J Control Release 2009; 137:185-95. [PMID: 19374931 DOI: 10.1016/j.jconrel.2009.04.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2009] [Revised: 04/07/2009] [Accepted: 04/07/2009] [Indexed: 10/20/2022]
Abstract
Poly(d,l-lactic-co-glycolic acid) (PLGA) polymers having different average molecular weights were chemically conjugated to two imidazopyridinacetamides (1 and 2), chosen as model Peripheral Benzodiazepine Receptor (PBR) ligands, via an ester or amide linkage. It is in order to evaluate these conjugates as delivery systems of PBR ligands endowed with apoptosis inducing activity. Various coupling reaction conditions were tested to optimize the conjugation process. After purification by extensive dialysis procedures, the macromolecular conjugates were characterized by FT-IR, UV, (1)H NMR spectroscopy, DSC and the average molecular weights of synthesized conjugates were determined by GPC. PBR ligand released from these conjugates occurred in human serum and in 0.1 N HCl solution at a faster rate than that observed in phosphate buffer, pH 7.4. Moreover, the macromolecular conjugates displayed high affinity and selectivity for PBR. Cytotoxicity studies demonstrated that PBR ligand-PLGA polymer conjugates induce survival inhibition in rat C6 glioma cell line. Fluorescence microscopy studies evidenced the cellular uptake of FITC-conjugated probes 10 and 11 and moreover, the mitochondrial morphology modification induced by compounds 1 and 4a. Therefore, this study demonstrates that this PBR ligand-PLGA combination may provide a new mitochondrial targeted approach useful for improved cancer chemotherapy.
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Affiliation(s)
- Valentino Laquintana
- Pharmaco-Chemistry Department, Faculty of Pharmacy, University of Bari, 70125 Bari, Italy
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13
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Saha B, Mukherjee A, Santra CR, Chattopadhyay A, Ghosh AN, Choudhuri U, Karmakar P. Alprazolam Intercalates into DNA. J Biomol Struct Dyn 2009; 26:421-9. [DOI: 10.1080/07391102.2009.10507257] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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14
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Doucet C, Milin S, Favreau F, Desurmont T, Manguy E, Hébrard W, Yamamoto Y, Mauco G, Eugene M, Papadopoulos V, Hauet T, Goujon JM. A p38 mitogen-activated protein kinase inhibitor protects against renal damage in a non-heart-beating donor model. Am J Physiol Renal Physiol 2008; 295:F179-91. [PMID: 18448593 DOI: 10.1152/ajprenal.00252.2007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Ischemia-reperfusion injury is one of the central nonimmunologic processes involved in renal allograft dysfunction. Kidneys from non-heart beating donors (NHBD) exhibit higher rates of delayed graft function (DGF) than those from other donors. Primary nonfunction and DGF are the main barriers to the use of kidneys from NHBD. Using a pig model of NHBD transplantation, we studied the effect of FR167653 (a p38 MAP kinase inhibitor) on the recovery and reparation of kidneys exposed to both warm (WI: 1 h) and cold ischemia (24 h). Our results demonstrate that the addition of FR167653 increases the kinetics of proximal tubule cell regeneration after 60 min of WI. Hypoxia-inducible factor and vascular endothelial growth factor expression was also more important in FR167653-treated kidneys compared with those in nontreated groups. Also, expression of peripheral-type benzodiazepine receptor, involved in tissue repair, was increased in the FR167653-treated groups. At 3 mo, the protective effects of FR167653 were accompanied by a reduction of long-term inflammation process and tubulointerstitial fibrosis development associated with a limitation of ischemia-induced remodeling. This study suggests that such treatment may be useful in protocols aimed at improving the quality of renal transplants from NHBD. In addition, the beneficial role of FR167653 in limiting early injury is associated with secondary reduction in development of tubular atrophy and interstitial fibrosis which are together the hallmark of failing renal transplants. The more efficient effect was observed when FR167653 was added in combination before WI, during cold storage and reperfusion.
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Affiliation(s)
- Carole Doucet
- Institut National de la Santé et de la Recherche Médicale U927, Université de Poitiers, Poitiers, France
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15
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Shih RSM, Wong SHK, Schoene NW, Lei KY. Suppression of Gadd45 alleviates the G2/M blockage and the enhanced phosphorylation of p53 and p38 in zinc supplemented normal human bronchial epithelial cells. Exp Biol Med (Maywood) 2008; 233:317-27. [PMID: 18296737 DOI: 10.3181/0708-rm-220] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
An adequate zinc status is essential for optimal cellular functions and growth. Yet, excessive zinc supplementation can be cytotoxic and can impair cell growth. Gadd45 plays a vital role as cellular stress sensor in the modulation of cell signal transduction in response to stress. The present study was designed to determine the influence of zinc status on Gadd45 expression and cell cycle progression in zinc deficient and supplemented normal human bronchial epithelial (NHBE) cells, and to decipher the molecular mechanism(s) exerted by the suppression of Gadd45 expression on cell growth and cell cycle progression in this cell type. Cells were cultured for one passage in different concentration of zinc: <0.4 muM (ZD) as severe zinc deficient; 4 muM as normal zinc level in culture medium; 16 microM (ZA) as normal human plasma zinc level; and 32 muM (ZS) as the high end of plasma zinc attainable by oral supplementation. Inhibition of cell growth, upregulation of Gadd45 mRNA and protein expression, and blockage of G2/M cell cycle progression were observed in ZS cells. In contrast, little or no changes in these parameters were seen in ZD cells. The siRNA-mediated knocking down of Gadd45 was found to relieve G2/M blockage in ZS cells, which indicated that the blockage was Gadd45 dependent. Moreover, the enhanced phosphorylation of p38 and p53 (ser15) in ZS cells was normalized after suppression of Gadd45 by siRNA, implicating that the enhanced phosphorylation of these proteins was Gadd45 dependent. Thus, we demonstrated for the first time that an elevated zinc status modulated signal transduction to produce a delay at G2/M during cell cycle progression in NHBE cells.
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Affiliation(s)
- Rita S M Shih
- Department of Nutrition and Food Science, University of Maryland, College Park, MD 20742, USA
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Mukhopadhyay S, Rajaratnam V, Mukherjee S, Das SK. Control of peripheral benzodiazepine receptor-mediated breast cancer in rats by soy protein. Mol Carcinog 2008; 47:310-9. [PMID: 17932947 DOI: 10.1002/mc.20387] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Soy protein is known to have breast tumor suppressing activity. The expression of peripheral benzodiazepine receptors (PBRs), currently renamed as translocator protein (TSPO) and their associated functions, such as nuclear cholesterol uptake and content also have been shown to be increased in breast cancer. Here we investigated whether the breast tumor suppressing effects of soy protein is mediated by down-regulation of PBR expression and function. Breast tumors were induced by gavage administration of a single dose (80 mg/kg) of dimethylbenz[a]anthracene (DMBA) into 50-d old female Sprague Dawley rats, maintained on a standard AIN-76A diet containing either casein or soy protein. Approximately 120 d following DMBA administration, the animals were sacrificed. All tumors were detected by palpation and at autopsy biopsy specimens were taken for histological grading. The ligand binding capacity, expression, and protein levels of PBRs, their nuclear localization and function, such as nuclear cholesterol uptake and content, were significantly increased in the tumors. However, replacement of casein by soy protein in the diet caused a significant decrease in all of these parameters. These data suggest that soy protein inhibits breast tumor development by decreasing the expression of the tumor-promoting gene, which encodes PBRs.
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Affiliation(s)
- Sutapa Mukhopadhyay
- Department of Biomedical Science, Meharry Medical College, Nashville, Tennessee 37208, USA
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17
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Kim DH, Lee JT, Lee IK, Ha JH. Comparative anticancer effects of flavonoids and diazepam in cultured cancer cells. Biol Pharm Bull 2008; 31:255-9. [PMID: 18239283 DOI: 10.1248/bpb.31.255] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study examined the comparative anticancer effects of flavonoids and diazepam in the cultured cancer cells. In the SNU-C4 colorectal and MDA-MB-231 breast adenocarcinoma cells, apigenin and fisetin, flavonoids, and diazepam inhibited cancer cell survival concentration and incubation-time dependently. Diazepam consistently inhibited FAS activity, a known anticancer mechanism of flavonoids, in a concentration dependent manner. Unlike diazepam, in highly aggressive breast MDA-MB-231 cells known to have a nuclear/perinuclear located PBR, PK11195, a specific PBR ligand enhanced the proliferation of cells, and the proliferative effect of PK11195 was reversed by an addition of lovastatin, a HMG-CoA reductase inhibitor. Diazepam- and flavonoids-induced cytotoxic activity in both cancer cell lines was not reduced by the addition of 5-fluorouracil (5-FU), a chemotherapeutic agent. Like flavonoids, diazepam inhibited the release of vascular endothelial growth factor (VEGF) and granulocyte-macrophage-colony stimulating factor (GM-CSF) into supernatants of cultured in the SNU-C4 and MDA-MB-231 cells. In conclusion, this study provided in vitro information on the safe use of sedative in oncologic patients.
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Affiliation(s)
- Dae-Hyun Kim
- Nuclear Medicine, School of Medicine, Kyungpook National University, Jung-Gu, Daegu, Republic of Korea
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18
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Laquintana V, Denora N, Lopedota A, Suzuki H, Sawada M, Serra M, Biggio G, Latrofa A, Trapani G, Liso G. N-Benzyl-2-(6,8-dichloro-2-(4-chlorophenyl)imidazo[1,2-a]pyridin-3-yl)-N-(6- (7-nitrobenzo[c][1,2,5]oxadiazol-4-ylamino)hexyl)acetamide as a New Fluorescent Probe for Peripheral Benzodiazepine Receptor and Microglial Cell Visualization. Bioconjug Chem 2007; 18:1397-407. [PMID: 17722875 DOI: 10.1021/bc060393c] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The aim of this work was to develop new fluorescent probes for the localization and function of the peripheral benzodiazepine receptor (PBR). This receptor is primarily expressed on the mitochondria, and it is overexpressed in a variety of different states including glioma, breast cancer, Alzeheimer's disease, and activated microglia. For the mentioned purpose, imidazopyridine and imidazopyrimidine compounds 5-20 were synthesized, and their affinity for PBR was determined. Although some intrinsically fluorescent imidazopyrimidine compounds 12-20 possess good binding affinity, they cannot be used for visualizing PBR due to their unfavorable fluorescence characteristics. Among the imidazopyridine-7-nitrofurazan conjugates 5-11, compound 10 was the most active, and it was found to stain live Ra2 microglial cells effectively. An in vivo biodistribution study carried out on compound 10 showed that this imidazopyridine derivative, injected in the carotid artery, is able to penetrate to liver parenchyma, whereas fluorescein isothiocyanate labeled dextran (FITC-dextran), used as a control dye, hardly penetrated from blood vessels to tissues. On the other hand, as for the distribution to brain, the patterns of staining with 10 and FITC-dextran are similar, indicating that both of them hardly penetrate into the brain because of the existence of the blood-brain barrier. The obtained results indicate that compound 10 represents a new useful fluorescent probe for visualization of activated microglia and PBR.
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Affiliation(s)
- Valentino Laquintana
- Dipartimento Farmaco-Chimico, Facoltà di Farmacia, Università degli Studi di Bari, Via Orabona 4, 70125 Bari, Italy
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19
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Königsrainer I, Vogel UF, Beckert S, Sotlar K, Coerper S, Braun A, Lembert N, Steurer W, Königsrainer A, Kupka S. Increased Translocator Protein (TSPO) mRNA Levels in Colon but Not in Rectum Carcinoma. Eur Surg Res 2007; 39:359-63. [PMID: 17652962 DOI: 10.1159/000106380] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2007] [Accepted: 05/25/2007] [Indexed: 11/19/2022]
Abstract
BACKGROUND The peripheral-type benzodiazepine receptor or translocator protein (TSPO) is an 18-kDa protein involved in cell proliferation and apoptosis. TSPO was shown to be overexpressed in malignant tumors and cancer cell lines, correlating with enhanced malignant behavior. The present study analyzed the role of TSPO in patients with colorectal carcinomas. METHODS Tumor tissues and corresponding normal mucosa from 55 patients who underwent resection for colorectal carcinomas were analyzed for TSPO expression in correlation to GAPDH expression(glyceraldehyde-3-phosphate dehydrogenase) using a multiplex RT-PCR assay. RESULTS TSPO was overexpressed in 67% of the tumors in comparison to corresponding normal mucosa, and positivity as well as expression levels in colon carcinomas were significantly higher than in the rectum carcinomas. In contrast, TSPO expression was not different in intermediate versus high-grade tumors or in lymph node-positive versus -negative patients. CONCLUSION The differences in TSPO expression between colon and rectum carcinoma may imply that these tumors are of different biological behavior.
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Affiliation(s)
- I Königsrainer
- Department of General, Visceral and Transplant Surgery, Tübingen University Hospital, Tübingen, Germany.
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20
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Gourdeau H, McAlpine JB, Ranger M, Simard B, Berger F, Beaudry F, Farnet CM, Falardeau P. Identification, characterization and potent antitumor activity of ECO-4601, a novel peripheral benzodiazepine receptor ligand. Cancer Chemother Pharmacol 2007; 61:911-21. [PMID: 17622531 DOI: 10.1007/s00280-007-0544-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2007] [Accepted: 06/05/2007] [Indexed: 10/23/2022]
Abstract
PURPOSE ECO-4601 is a structurally novel farnesylated dibenzodiazepinone discovered through DECIPHER technology, Thallion's proprietary drug discovery platform. The compound was shown to have a broad cytotoxic activity in the low micromolar range when tested in the NCI 60 cell line panel. In the work presented here, ECO-4601 was further evaluated against brain tumor cell lines. Preliminary mechanistic studies as well as in vivo antitumor evaluation were performed. METHODS Since ECO-4601 has a benzodiazepinone moiety, we first investigated if it binds the central and/or peripheral benzodiazepine receptors. ECO-4601 was tested in radioligand binding assays on benzodiazepine receptors obtained from rat hearts. The ability of ECO-4601 to inhibit the growth of CNS cancers was evaluated on a panel of mouse, rat and human glioma cell lines using a standard MTT assay. Antitumor efficacy studies were performed on gliomas (rat and human), human breast and human prostate mouse tumor xenografts. Antitumor activity and pharmacokinetic analysis of ECO-4601 was evaluated following intravenous (i.v.), subcutaneous (s.c.), and intraperitoneal (i.p.) bolus administrations. RESULTS ECO-4601 was shown to bind the peripheral but not the central benzodiazepine receptor and inhibited the growth of CNS tumor cell lines. Bolus s.c. and i.p. administration gave rise to low but sustained drug exposure, and resulted in moderate to significant antitumor activity at doses that were well tolerated. In a rat glioma (C6) xenograft model, ECO-4601 produced up to 70% tumor growth inhibition (TGI) while in a human glioma (U-87MG) xenograft, TGI was 34%. Antitumor activity was highly significant in both human hormone-independent breast (MDA-MB-231) and prostate (PC-3) xenografts, resulting in TGI of 72 and 100%, respectively. On the other hand, i.v. dosing was followed by rapid elimination of the drug and was ineffective. CONCLUSIONS Antitumor efficacy of ECO-4601 appears to be associated with the exposure parameter AUC and/or sustained drug levels rather than C (max). These in vivo data constitute a rationale for clinical studies testing prolonged continuous administration of ECO-4601.
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Affiliation(s)
- Henriette Gourdeau
- Thallion Pharmaceuticals Inc., 7150 Alexander-Fleming, St Laurent, QC, Canada H4S 2C8.
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21
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Doucet C, Zhang K, Desurmont T, Hebrard W, Scepi M, Nadeau C, Cau J, Leyre P, Febrer G, Carretier M, Richer JP, Papadopoulos V, Hauet T, Burucoa C, Goujon JM. Influence of warm ischemia time on peripheral-type benzodiazepine receptor: a new aspect of the role of mitochondria. Nephron Clin Pract 2007; 107:e1-11. [PMID: 17622771 DOI: 10.1159/000105139] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2006] [Accepted: 01/11/2007] [Indexed: 11/19/2022] Open
Abstract
The peripheral benzodiazepine receptor (PBR) is located mainly in the outer mitochondrial membrane and many functions are associated directly or indirectly with the PBR. We have studied the influence of different durations of warm ischemia (WI) on renal function, tissue damage and PBR expression in a Large Whitepig model. After a midline incision, the renal pedicle was clamped for 10 (WI10), 30 (WI30), 45 (WI45), 60 (WI60) or 90 min (WI90), and blood and renal tissue samples were collected between 1 day and 2 weeks after reperfusion for assessment of renal function. Metabolite excretion associated with renal ischemia reperfusion injury such as trimethylamine-N-oxide (TMAO) was quantified in blood by magnetic resonance spectroscopy. PBR mRNA and protein expression were determined in renal tissue. TMAO levels rose progressively and significantly with increasing duration of WI. PBR mRNA expression was upregulated between 3 h and 1 day after reperfusion in WI30, WI45 and WI60. Its upregulation was noted 3 days after reperfusion in WI90. At day 14, PBR transcript expression was not different from basal level in any group. PBR protein followed the same pattern. These findings suggest a new role for PBR which could be a major target in the regeneration process during ischemia reperfusion.
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Affiliation(s)
- Carole Doucet
- Inserm, E0 324, Poitiers and Université Poitiers, Poitiers, France
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22
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Cleary J, Johnson KM, Opipari AW, Glick GD. Inhibition of the mitochondrial F1F0-ATPase by ligands of the peripheral benzodiazepine receptor. Bioorg Med Chem Lett 2007; 17:1667-70. [PMID: 17251020 DOI: 10.1016/j.bmcl.2006.12.102] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2006] [Accepted: 12/22/2006] [Indexed: 11/25/2022]
Abstract
Although PK11195 binds to the peripheral benzodiazepine receptor with nanomolar affinity, significant data exist which suggest that it has another cellular target distinct from the PBR. Here we demonstrate that PK11195 inhibits F(1)F(0)-ATPase activity in an OSCP-dependent manner, similar to the pro-apoptotic benzodiazepine Bz-423. Importantly, our data indicate that cellular responses observed with micromolar concentrations of PK11195, which are commonly attributed to modulation of the PBR, are likely a direct result of mitochondrial F(1)F(0)-ATPase inhibition.
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Affiliation(s)
- Joanne Cleary
- Department of Chemistry, University of Michigan, 930 N University Ave., Ann Arbor, MI 48109-1055, USA
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Vemuganti R, Kalluri H, Yi JH, Bowen KK, Hazell AS. Gene expression changes in thalamus and inferior colliculus associated with inflammation, cellular stress, metabolism and structural damage in thiamine deficiency. Eur J Neurosci 2006; 23:1172-88. [PMID: 16553781 DOI: 10.1111/j.1460-9568.2006.04651.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Identification of gene expression changes that promote focal neuronal death and neurological dysfunction can further our understanding of the pathophysiology of these disease states and could lead to new pharmacological and molecular therapies. Impairment of oxidative metabolism is a pathogenetic mechanism underlying neuronal death in many chronic neurodegenerative diseases as well as in Wernicke's encephalopathy (WE), a disorder induced by thiamine deficiency (TD). To identify functional pathways that lead to neuronal damage in this disorder, we have examined gene expression changes in the vulnerable thalamus and inferior colliculus of TD rats using Affymetrix Rat Genome GeneChip analysis in combination with gene ontology and functional categorization assessment utilizing the NetAffx GO Mining Tool. Of the 15 927 transcripts analysed, 125 in thalamus and 141 in inferior colliculus were more abundantly expressed in TD rats compared with control animals. In both regions, the major functional categories of transcripts that were increased in abundance after TD were those associated with inflammation (approximately 33%), stress (approximately 20%), cell death and repair ( approximately 26%), and metabolic perturbation (approximately 19%), together constituting approximately 98% of all transcripts up-regulated. These changes occurred against a background of neuronal cell loss and reactive astro- and microgliosis in both structures. Our results indicate that (i) TD produces changes in gene expression that are consistent with the observed dysfunction and pathology, and (ii) similar alterations in expression occur in thalamus and inferior colliculus, brain regions previously considered to differ in pathology. These findings provide important new insight into processes responsible for lesion development in TD, and possibly WE.
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Affiliation(s)
- Raghu Vemuganti
- Department of Neurological Surgery, University of Wisconsin, Madison, USA
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24
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Huether A, Hopfner M, Sutter AP, Baradari V, Schuppan D, Scherubl H. Signaling pathways involved in the inhibition of epidermal growth factor receptor by erlotinib in hepatocellular cancer. World J Gastroenterol 2006; 12:5160-7. [PMID: 16937526 PMCID: PMC4088013 DOI: 10.3748/wjg.v12.i32.5160] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To examine the underlying mechanisms of erlotinib-induced growth inhibition in hepatocellular carcinoma (HCC).
METHODS: Erlotinib-induced alterations in gene expression were evaluated using cDNA array technology; changes in protein expression and/or protein activation due to erlotinib treatment as well as IGF-1-induced EGFR transactivation were investigated using Western blotting.
RESULTS: Erlotinib treatment inhibited the mitogen activated protein (MAP)-kinase pathway and signal transducer of activation and transcription (STAT)-mediated signaling which led to an altered expression of apoptosis and cell cycle regulating genes as demonstrated by cDNA array technology. Overexpression of proapoptotic factors like caspases and gadds associated with a down-regulation of antiapoptotic factors like Bcl-2, Bcl-XL or jun D accounted for erlotinib's potency to induce apoptosis. Downregulation of cell cycle regulators promoting the G1/S-transition and overexpression of cyclin-dependent kinase inhibitors and gadds contributed to the induction of a G1/G0-arrest in response to erlotinib. Furthermore, we displayed the transactivation of EGFR-mediated signaling by the IGF-1-receptor and showed erlotinib’s inhibitory effects on the receptor-receptor cross talk.
CONCLUSION: Our study sheds light on the under-standing of the mechanisms of action of EGFR-TK-inhibition in HCC-cells and thus might facilitate the design of combination therapies that act additively or synergistically. Moreover, our data on the pathways responding to erlotinib treatment could be helpful in predicting the responsiveness of tumors to EGFR-TKIs in the future.
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Affiliation(s)
- Alexander Huether
- Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, Medical Clinic I, Gastroenterology/Infectious Diseases/Rheumatology, Berlin, Germany
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25
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Xu XH, Zhang HL, Han R, Gu ZL, Qin ZH. Enhancement of neuroprotection and heat shock protein induction by combined prostaglandin A1 and lithium in rodent models of focal ischemia. Brain Res 2006; 1102:154-62. [PMID: 16797496 DOI: 10.1016/j.brainres.2006.04.111] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2006] [Revised: 04/20/2006] [Accepted: 04/27/2006] [Indexed: 12/20/2022]
Abstract
Both prostaglandin A(1) (PGA(1)) and lithium have been reported to protect neurons against excitotoxic and ischemic injury. The present study was undertaken to examine the effects of lithium and PGA1 on heat shock proteins (HSP) and the growth arrest and DNA-damage-inducible gene (GADD153) and to evaluate if lithium could potentiate PGA(1)'s neuroprotective effects against cerebral ischemia. Rats were pretreated with a subcutaneous injection of lithium for 2 days and a single intracerebral ventricle administration of PGA(1) 15 min before ischemic insult. Brain ischemia was induced by a permanent middle cerebral artery occlusion. The infarct volume, motor behavior deficits and brain edema were analyzed 24 h after ischemic insult. The result showed that PGA(1) significantly reduced infarct volume, neurological deficits and brain edema. Except for neurological deficit, lithium enhanced PGA(1)'s neuroprotection. The neuroprotective effects of PGA(1) were associated with an up-regulation of cytoprotective heat shock proteins HSP70 and GRP78 in the ischemic brain hemisphere as determined by immunoblotting and immunofluorescence. The induction of HSP70 and GRP78 was enhanced by lithium. However, although the expression of GADD153 was enhanced significantly after pMCAO, it was not influenced by either PGA(1) or lithium or their combination. These studies suggest that lithium can potentiate PGA(1)'s neuroprotective effects and thus may have potential clinical value for the treatment of stroke in combination with other neuroprotective agents.
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Affiliation(s)
- Xi-Hui Xu
- Department of Pharmacology, Soochow University School of Medicine, Suzhou-Singopore Industrial Park, Suzhou, China
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26
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Höpfner M, Huether A, Sutter AP, Baradari V, Schuppan D, Scherübl H. Blockade of IGF-1 receptor tyrosine kinase has antineoplastic effects in hepatocellular carcinoma cells. Biochem Pharmacol 2006; 71:1435-48. [PMID: 16530734 DOI: 10.1016/j.bcp.2006.02.006] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2005] [Revised: 01/26/2006] [Accepted: 02/03/2006] [Indexed: 12/14/2022]
Abstract
UNLABELLED Hepatocellular carcinoma (HCC) is one of the most common cancer-related causes of death worldwide. Due to very poor 5-year-survival new therapeutic approaches are mandatory. Most HCCs express insulin-like growth factors and their receptors (IGF-R). As IGF-1R-mediated signaling promotes survival, oncogenic transformation and tumor growth and spread, it represents a potential target for innovative treatment strategies of HCC. Here we studied the antineoplastic effects of inhibiting IGF-1R signaling in HCC cells by the novel IGF-1R tyrosine kinase inhibitor NVP-AEW541. METHODS AND RESULTS NVP-AEW541 induced a time- and dose-dependent growth inhibition in the human hepatoblastoma and hepatocellular carcinoma cell lines SK-Hep-1, Hep-3B, Hep-G2 and Huh-7. Measurement of LDH-release showed that the antineoplastic effect of NVP-AEW541 was not due to cytotoxicity. Instead NVP-AEW541 induced apoptosis as evidenced by both caspase-3 and -8 activation as well as by apoptosis-specific morphological and mitochondrial changes. In addition, nuclear degradation was monitored by DNA-laddering. NVP-AEW541-treatment suppressed the expression of the antiapoptotic proteins Bcl-2 and survivin, while the expression of the proapoptotic protein BAX was stimulated in a dose-dependent manner. Moreover, NVP-AEW541 arrested the cell cycle at the G1/S checkpoint. When NVP-AEW541 was combined with cytotoxic chemotherapy or with a specific epidermal growth factor receptor antibody additive antiproliferative effects were observed. INTERPRETATION Inhibition of IGF-1R tyrosine kinase (IGF-1R-TK) by NVP-AEW541 induces growth inhibition, apoptosis and cell cycle arrest in human HCC cell lines without accompanying cytotoxicity. Thus, IGF-1R-TK inhibition may be a promising novel treatment approach in HCC.
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Affiliation(s)
- Michael Höpfner
- Charité, Universitätsmedizin Berlin, Campus Benjamin Franklin, Medical Clinic I, Gastroenterology/Infectious Diseases/Rheumatology, 12200 Berlin, Germany
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27
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Sutter AP, Maaser K, Höpfner M, Huether A, Schuppan D, Scherübl H. Cell cycle arrest and apoptosis induction in hepatocellular carcinoma cells by HMG-CoA reductase inhibitors. Synergistic antiproliferative action with ligands of the peripheral benzodiazepine receptor. J Hepatol 2005; 43:808-16. [PMID: 16083991 DOI: 10.1016/j.jhep.2005.04.010] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2004] [Revised: 03/03/2005] [Accepted: 04/04/2005] [Indexed: 12/04/2022]
Abstract
BACKGROUND/AIMS Hepatocellular carcinoma (HCC) is the fifth most common cause of cancer deaths worldwide. Inhibitors of cholesterol biosynthesis ('statins') have been proposed as promising adjunctive anticancer agents to treat HCC, but their mode of action is yet poorly characterized. We additionally investigated the potential benefit of a combination of peripheral benzodiazepine receptor (PBR) ligands and statins. METHODS We analyzed the growth inhibitory effects of PBR ligands, statins, and their combination in two human HCC cell lines. Moreover, we investigated the regulation of cellular cholesterol levels and the expression of 3-hydroxy-3-methylglutaryl coenzyme-A reductase (HMG-CoAR), the target of statins. RESULTS Statins inhibited the proliferation of HCC cells by inducing apoptosis and G1/S cell cycle arrest. Statin-induced apoptosis was characterized by a breakdown of the mitochondrial membrane potential, caspase activation and nuclear degradation. Furthermore, activation of ERK1/2 was downregulated while p38MAPK was activated. Synergistic growth inhibition was obtained by the combination of the PBR ligand FGIN-1-27 with statins. PBR ligands induced a decrease of HMG-CoAR expression. This downregulation may be responsible for the enhanced sensitivity of HCC cells to statins. CONCLUSIONS Our data shed light on the signaling cascades mediating statin-induced growth inhibition of HCC cells. Moreover, PBR ligands sensitized HCC cells to statins, suggesting a new strategy to treat HCC.
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Affiliation(s)
- Andreas P Sutter
- Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, Medical Clinic I, Berlin, Germany
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28
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Chelli B, Rossi L, Da Pozzo E, Costa B, Spinetti F, Rechichi M, Salvetti A, Lena A, Simorini F, Vanacore R, Scatena F, Da Settimo F, Gremigni V, Martini C. PIGA (N,N-Di-n-butyl-5-chloro-2-(4-chlorophenyl)indol-3-ylglyoxylamide), a new mitochondrial benzodiazepine-receptor ligand, induces apoptosis in C6 glioma cells. Chembiochem 2005; 6:1082-8. [PMID: 15883977 DOI: 10.1002/cbic.200400350] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Mitochondrial benzodiazepine-receptor (mBzR) ligands constitute a heterogeneous class of compounds that show a pleiotropic spectrum of effects within the cells, including the modulation of apoptosis. In this paper, a novel synthetic 2-phenylindol-3-ylglyoxylamide derivative, N,N-di-n-butyl-5-chloro-2-(4-chlorophenyl)indol-3-ylglyoxylamide (PIGA), which shows high affinity and selectivity for the mBzR, is demonstrated to induce apoptosis in rat C6 glioma cells. PIGA was able to dissipate mitochondrial transmembrane potential (DeltaPsim) and to cause a significant cytosolic accumulation of cytochrome c. Moreover, typical features of apoptotic cell death, such as caspase-3 activation and DNA fragmentation, were also detected in PIGA-treated cells. Our data expand the knowledge on mBzR ligand-mediated apoptosis and suggest PIGA as a novel proapoptotic compound with therapeutic potential against glial tumours, in which apoptosis resistance has been reported to be involved in carcinogenesis.
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Affiliation(s)
- Beatrice Chelli
- Department of Psychiatry, Neurobiology, Pharmacology and Biotechnology, University of Pisa, Via Bonanno 6, 56126 Pisa, Italy
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29
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Gonzalez-Polo RA, Carvalho G, Braun T, Decaudin D, Fabre C, Larochette N, Perfettini JL, Djavaheri-Mergny M, Youlyouz-Marfak I, Codogno P, Raphael M, Feuillard J, Kroemer G. PK11195 potently sensitizes to apoptosis induction independently from the peripheral benzodiazepin receptor. Oncogene 2005; 24:7503-13. [PMID: 16091749 DOI: 10.1038/sj.onc.1208907] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
1-(2-Chlorophenyl-N-methylpropyl)-3-isoquinolinecarboxamide (PK11195) is a prototypic ligand of the peripheral benzodiazepine receptor (PBR), a mitochondrial outer membrane protein. PK11195 can be used to chemosensitize tumor cells to a variety of chemotherapeutic agents, both in vitro and in vivo. PK11195 has been suggested to exert this effect via inhibition of the multiple drug resistance (MDR) pump and by direct mitochondrial effects which could be mediated by the PBR. Here, we established a model system in which PK11195 and another PBR ligand, 7-chloro-5-(4-chlorophenyl)-1,3-dihydro-1-methyl-2H-1,4-benzodiazepin-2-one (Ro5-4864), sensitize to nutrient depletion-induced cell death. In this MDR-independent model, PK11195 and Ro5-4864 are fully active even when the PBR is knocked down by small interfering RNA. Cells that lack PBR possess low-affinity binding sites for PK11195 and Ro5-4864. The starvation-sensitizing effects of PK11195 are not due to a modulation of the adaptive response of starved cells, namely autophagy and NF-kappaB activation. Rather, it appears that the combination of PK11195 with autophagy or NF-kappaB inhibitors has a potent synergistic death-inducing effect. Starved cells treated with PK11195 exhibit characteristics of apoptosis, including loss of the mitochondrial transmembrane potential, mitochondrial cytochrome c release, caspase activation and chromatin condensation. Accordingly, stabilization of mitochondria by overexpression of Bcl-2 or expression of the viral mitochondrial inhibitor (vMIA) from cytomegalovirus inhibits cell death induced by PK11195 plus starvation. Thus, PK11195 potently sensitizes to apoptosis via a pathway that involves mitochondria, yet does not involve the PBR.
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Affiliation(s)
- Rosa-Ana Gonzalez-Polo
- 1Centre National de la Recherche Scientifique, UMR8125, Institut Gustave Roussy, Pavillon de Recherche 1, 39 rue Camille-Desmoulins, 94805 Villejuif, France
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Gebicke-Haerter PJ. Microarrays and expression profiling in microglia research and in inflammatory brain disorders. J Neurosci Res 2005; 81:327-41. [PMID: 15948185 DOI: 10.1002/jnr.20479] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Expression profiling by using microarrays is a powerful tool for investigating transcriptional changes in a variety of diseases. In this survey, microarray data selected from the literature from in vivo and in vitro studies are scrutinized to find differentially expressed genes in common within specific inflammatory conditions in brain or microglial cell cultures, if there are at least two independent investigations available. Viral encephalitis, multiple sclerosis, epileptic seizures, ischemic lesions, and traumatic brain injury are the disorders covered. Moreover, by taking into account expression data obtained from cultured microglia, two examples are presented of how one can deal (or should not deal) with lists of candidate genes showing up in these kinds of studies without sophisticated software programs. Finally, some general remarks are made about pivotal issues when beginning to use microarray technology.
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Park SY, Cho N, Chang I, Chung JH, Min YK, Lee MK, Kim KW, Kim SJ, Lee MS. Effect of PK11195, a peripheral benzodiazepine receptor agonist, on insulinoma cell death and insulin secretion. Apoptosis 2005; 10:537-44. [PMID: 15909116 DOI: 10.1007/s10495-005-1884-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Functional role of peripheral benzodiazepine receptor on mitochondrial membrane in apoptosis and insulin secretion from insulinoma cells was studied. A prototypic peripheral benzodiazepine receptor agonist PK11195 induced insulinoma cell apoptosis, while a central benzodiazepine receptor agonist did not. Death of insulinoma cells by PK11195 was inhibited by cyclosporin A, a blocker of mitochondrial permeability transition pore. Caspase inhibitors further inhibited MIN6N8 cell death. PK11195 induced dissipation of mitochondrial potential and cytochrome c translocation to cytoplasm. PK11195 induced an increase in cytoplasmic [Ca(2+)], which was reversed by cyclosporin A. Rhod-2 staining showed decreased mitochondrial [Ca(2+)] after PK11195 treatment. PK11195 potentiated glucose-induced insulin secretion probably due to the increased cytoplasmic [Ca(2+)]. Calpain was activated following Ca(2+) release, and calpain inhibitors attenuated death of insulinoma cells by PK11195. These results suggest that PK11195 induces mitochondrial potential loss, cytochrome c translocation, increased insulin secretion in conjunction with an increase in cytoplasmic [Ca(2+)] and calpain activation, which collectively leads to apoptosis of insulinoma cells.
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Affiliation(s)
- S Y Park
- Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, Korea
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Maaser K, Grabowski P, Oezdem Y, Krahn A, Heine B, Stein H, Buhr H, Zeitz M, Scherübl H. Up-Regulation of the Peripheral Benzodiazepine Receptor during Human Colorectal Carcinogenesis and Tumor Spread. Clin Cancer Res 2005; 11:1751-6. [PMID: 15755996 DOI: 10.1158/1078-0432.ccr-04-1955] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The peripheral benzodiazepine receptor (PBR) is overexpressed in a variety of cancers. In Unio Internationale Contra Cancrum (UICC) III colorectal cancers, a high level of PBR overexpression correlates with poor prognosis. However, little is known about the role of PBR in the development and progression of colorectal cancer. This study addresses the up-regulation of PBR during colorectal carcinogenesis and tumor spread. One hundred sixteen consecutive patients undergoing surgery for colorectal cancer with either regional (59 patients) or distant metastases (57 patients) were followed-up for 5 years or until death. Twenty-four of the 59 patients with initial UICC stage III cancers later developed distant metastases. PBR overexpression in tumor specimens was determined by immunohistochemistry. UICC stage III patients with colorectal primaries highly overexpressing PBR developed metastases significantly more often than patients with low PBR overexpression in their primary carcinoma. In 54 of the 116 patients adenomas and/or metastases and/or recurrences were available to be studied for PBR up-regulation during colorectal carcinogenesis and tumor spread. PBR was found to be overexpressed in 86% of early and late adenomas. Furthermore, 85% of primaries and of 86% of metastases displayed PBR overexpression. PBR overexpression was also detected at the mRNA level as revealed by real-time PCR. The extent of PBR protein overexpression was equivalent in colorectal adenomas and carcinomas but slightly increased in metastases. These data suggest a functional role of PBR during colorectal carcinogenesis and tumor spread. Thus, PBR qualifies as a target for innovative diagnostic and therapeutic approaches.
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Affiliation(s)
- Kerstin Maaser
- Medical Clinic I, Institute of Pathology, and Department of Surgery, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12200 Berlin, Germany
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33
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Hans G, Wislet-Gendebien S, Lallemend F, Robe P, Rogister B, Belachew S, Nguyen L, Malgrange B, Moonen G, Rigo JM. Peripheral benzodiazepine receptor (PBR) ligand cytotoxicity unrelated to PBR expression. Biochem Pharmacol 2005; 69:819-30. [PMID: 15710359 DOI: 10.1016/j.bcp.2004.11.029] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2004] [Accepted: 11/29/2004] [Indexed: 10/25/2022]
Abstract
Some synthetic ligands of the peripheral-type benzodiazepine receptor (PBR), an 18 kDa protein of the outer mitochondrial membrane, are cytotoxic for several tumor cell lines and arise as promising chemotherapeutic candidates. However, conflicting results were reported regarding the actual effect of these drugs on cellular survival ranging from protection to toxicity. Moreover, the concentrations needed to observe such a toxicity were usually high, far above the affinity range for their receptor, hence questioning its specificity. In the present study, we have shown that micromolar concentrations of FGIN-1-27 and Ro 5-4864, two chemically unrelated PBR ligands are toxic for both PBR-expressing SK-N-BE neuroblastoma cells and PBR-deficient Jurkat lymphoma cells. We have thereby demonstrated that the cytotoxicity of these drugs is unrelated to their PBR-binding activity. Moreover, Ro 5-4864-induced cell death differed strikingly between both cell types, being apoptotic in Jurkat cells while necrotic in SK-N-BE cells. Again, this did not seem to be related to PBR expression since Ro 5-4864-induced death of PBR-transfected Jurkat cells remained apoptotic. Taken together, our results show that PBR is unlikely to mediate all the effects of these PBR ligands. They however confirm that some of these ligands are very effective cytotoxic drugs towards various cancer cells, even for reputed chemoresistant tumors such as neuroblastoma, and, surprisingly, also for PBR-lacking tumor cells.
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Affiliation(s)
- Gregory Hans
- Centre of Cellular and Molecular Neurobiology, Université de Liège, 17 Place Delcour, 4020 Liège 2, Belgium.
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Jordà EG, Jiménez A, Verdaguer E, Canudas AM, Folch J, Sureda FX, Camins A, Pallàs M. Evidence in favour of a role for peripheral-type benzodiazepine receptor ligands in amplification of neuronal apoptosis. Apoptosis 2005; 10:91-104. [PMID: 15711925 DOI: 10.1007/s10495-005-6064-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The mitochondrial peripheral benzodiazepine receptor (PBR) is involved in a functional structure designated as the mitochondrial permeability transition (MPT) pore, which controls apoptosis. PBR expression in nervous system has been reported in glial and immune cells. We now show expression of both PBR mRNA and protein, and the appearance of binding of a synthetic ligand fluo-FGIN-1-27 in mitochondria of rat cerebellar granule cells (CGCs). Additionally, the effect of PBR ligands on colchicine-induced apoptosis was investigated. Colchicine-induced neurotoxicity in CGCs was measured at 24 h. We show that, in vitro, PBR ligands 1-(2-chlorophenyl-N-methylpropyl)-3-isoquinolinecarboxamide (PK11195), 7-chloro-5-(4-chlorophenyl)-1,3-dihydro-1-methyl-2H-1,4- benzodiazepin-2-one (Ro5-4864) and diazepam (25- 50 microM) enhanced apoptosis induced by colchicine, as demonstrated by viability experiments, flow cytometry and nuclear chromatin condensation. Enhancement of colchicine-induced apoptosis was characterized by an increase in mitochondrial release of cytochrome c and AIF proteins and an enhanced activation of caspase-3, suggesting mitochondrion dependent mechanism that is involved in apoptotic process. Our results indicate that exposure of neural cells to PBR ligands generates an amplification of apoptotic process induced by colchicine and that the MPT pore may be involved in this process.
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Affiliation(s)
- E G Jordà
- Unitat de Farmacologia i Farmacognòsia, Facultat de Farmàcia, Universitat de Barcelona, Nucli Universitari de Pedralbes, E-08028, Barcelona, Spain
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Maaser K, Sutter AP, Krahn A, Höpfner M, Grabowski P, Scherübl H. Cell cycle-related signaling pathways modulated by peripheral benzodiazepine receptor ligands in colorectal cancer cells. Biochem Biophys Res Commun 2004; 324:878-86. [PMID: 15474510 DOI: 10.1016/j.bbrc.2004.09.127] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2004] [Indexed: 01/17/2023]
Abstract
Specific ligands of the peripheral benzodiazepine receptor (PBR) have been shown to induce both apoptosis and G1/G0 cell cycle arrest in colorectal cancers. The signaling pathways leading to cell cycle arrest are still unknown. Using cDNA array technology, we identified signaling molecules involved in cell cycle arrest induced by the PBR ligands FGIN-1-27 and PK 11195. Differential gene expression was confirmed by semi-quantitative RT-PCR or Western blot analysis of gene products. The PBR ligand-mediated signaling involved the upregulation of the cyclin-dependent kinase inhibitors p21WAF1/CIP1 and p27Kip1, cdc16, and the cell cycle inhibitors gadd45 and gadd153, the downregulation of the cyclins D1 and B1, as well as the inactivation of ERK1/2. The p21-deficient colorectal cancer cell line HCT116 p21-/- was significantly less sensitive to PBR ligands than the parental HCT116 wild-type cells, demonstrating the functional involvement of p21WAF1/CIP1 in PBR ligand-mediated G1 arrest. This study thus revealed PBR ligand-triggered signaling pathways leading to cell cycle arrest. Moreover, we showed the functional implication and interaction of differentially expressed gene products and provided a model of signaling pathways involved in PBR ligand-induced G1 arrest. These results form the basis for future PBR ligand-mediated therapeutic approaches.
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Affiliation(s)
- Kerstin Maaser
- Medical Clinic I, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, 12200 Berlin, Germany
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36
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Trapani G, Laquintana V, Denora N, Trapani A, Lopedota A, Latrofa A, Franco M, Serra M, Pisu MG, Floris I, Sanna E, Biggio G, Liso G. Structure−Activity Relationships and Effects on Neuroactive Steroid Synthesis in a Series of 2-Phenylimidazo[1,2-a]pyridineacetamide Peripheral Benzodiazepine Receptors Ligands. J Med Chem 2004; 48:292-305. [PMID: 15634024 DOI: 10.1021/jm049610q] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of 36 imidazopyridineacetamides (2-37) were designed and synthesized to evaluate the effects of structural changes on the amide nitrogen at both central (CBRs) and peripheral benzodiazepine receptors (PBRs). These changes include variations in the length and number of the alkyl groups as well as introduction of different aromatic, heteroaromatic, and conformationally constrained groups. The affinities of these compounds for CBRs and PBRs were determined, and the results indicate that bulkiness of the substituents, their branching, and length beyond an optimal value may cause hindrance to the ligand in its interaction with the receptor. The presence of aromatic or conformationally constrained substituents on the carboxamide nitrogen can be conducive to high affinity and selectivity. Furthermore, the ability of a subset of the most active ligands to stimulate synthesis of neuroactive steroids in plasma and brain was evaluated in vivo and in vitro. Compound 3 exhibited very marked effects on the peripheral and central synthesis of neuroactive steroids, while 36 (potent at subnanomolar level) showed a slight ability to affect neuroactive steroid content in the cerebral cortex.
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Affiliation(s)
- Giuseppe Trapani
- Dipartimento Farmaco-Chimico, Facoltà di Farmacia, Università degli Studi di Bari, Via Orabona 4, 70125 Bari, Italy.
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37
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Höpfner M, Sutter AP, Huether A, Schuppan D, Zeitz M, Scherübl H. Targeting the epidermal growth factor receptor by gefitinib for treatment of hepatocellular carcinoma. J Hepatol 2004; 41:1008-16. [PMID: 15582135 DOI: 10.1016/j.jhep.2004.08.024] [Citation(s) in RCA: 134] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2004] [Revised: 07/19/2004] [Accepted: 08/17/2004] [Indexed: 12/19/2022]
Abstract
BACKGROUND/AIMS Hepatocellular carcinoma (HCC) is one of the most common cancer-related causes of death worldwide. Due to very poor 5-year-survival new therapeutic approaches are mandatory. Gefitinib, an inhibitor of epidermal growth factor receptor tyrosine kinase (EGFR-TK), potently suppresses the growth of various tumors, but its effect on HCC remains unexplored. We therefore studied the antineoplastic potency of gefitinib in human HCC cells. RESULTS Gefitinib induced a time- and dose-dependent growth inhibition of the human HCC cell lines Huh-7 and HepG2. Gefitinib-treatment induced both mitochondria-dependent and -independent apoptosis. Changes in mitochondrial membrane potential and caspase-8 activation, followed by caspase-3 activation and nuclear degradation, were detected. Moreover, gefitinib induced cell cycle arrest at the G1/S checkpoint and decreased the phosphorylation of mitogen-activated protein kinase ERK1/2. Finally, gefitinib suppressed the expression of antiapoptotic Bcl-2 and Bcl-X(L), further rendering HCC cells prone to apoptosis. CONCLUSIONS Our data demonstrate that the inhibition of EGFR-TK by gefitinib induced growth inhibition, apoptosis and cell cycle arrest in human HCC cells. Thus, EGFR-TK inhibition appears to be a promising novel approach for future treatment strategies of HCC.
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Affiliation(s)
- Michael Höpfner
- Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, Medical Clinic I, Gastroenterology/Infectious Diseases/Rheumatology, Hindenburgdamm 30, 12200 Berlin, Germany
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38
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Sutter AP, Maaser K, Grabowski P, Bradacs G, Vormbrock K, Höpfner M, Krahn A, Heine B, Stein H, Somasundaram R, Schuppan D, Zeitz M, Scherübl H. Peripheral benzodiazepine receptor ligands induce apoptosis and cell cycle arrest in human hepatocellular carcinoma cells and enhance chemosensitivity to paclitaxel, docetaxel, doxorubicin and the Bcl-2 inhibitor HA14-1. J Hepatol 2004; 41:799-807. [PMID: 15519653 DOI: 10.1016/j.jhep.2004.07.015] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2004] [Revised: 06/21/2004] [Accepted: 07/12/2004] [Indexed: 12/12/2022]
Abstract
BACKGROUND/AIMS Hepatocellular carcinoma (HCC) is one of the most common causes of cancer deaths worldwide. Thus, novel therapies are urgently needed. A promising approach is the use of peripheral benzodiazepine receptor (PBR) ligands which inhibit the proliferation of various tumors. METHODS PBR expression both in human HCC cell lines and in tumor specimens of HCC patients was analyzed by RT-PCR and immunostaining. To evaluate PBR ligands for the treatment of HCC, we tested their effects on human HCC cells. RESULTS PBR was localized to the mitochondria both of HCC cell lines and tumor tissues of HCC patients. In contrast, normal liver did not express PBR. PBR ligands inhibited the proliferation of HCC cell lines by inducing apoptosis and cell cycle arrest. Apoptosis was characterized by a breakdown of the mitochondrial membrane potential, caspase-3 activation and nuclear degradation. Furthermore, pro-apoptotic Bax was overexpressed while anti-apoptotic Bcl-2 and Bcl-X(L) were suppressed. Cell cycle was arrested both at the G1/S- and G2/M-checkpoints. Synergistic anti-neoplastic effects were obtained by a combination of PBR ligands with cytostatic drugs (paclitaxel, docetaxel, doxorubicin), or with an experimental Bcl-2 inhibitor. CONCLUSIONS This is the first report on the induction of apoptosis and cell cycle arrest by PBR ligands in HCC cells. Moreover, PBR ligands sensitized HCC cells to taxans and doxorubicin.
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Affiliation(s)
- Andreas P Sutter
- Medical Clinic I, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12200 Berlin, Germany
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Yuan JP, Wang GH, Ling H, Su Q, Yang YH, Song Y, Tang RJ, Liu Y, Huang C. Diallyl disulfide-induced G2/M arrest of human gastric cancer MGC803 cells involves activation of p38 MAP kinase pathways. World J Gastroenterol 2004; 10:2731-4. [PMID: 15309729 PMCID: PMC4572203 DOI: 10.3748/wjg.v10.i18.2731] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
AIM: To determine the role of p38 MAP kinase signal transduction pathways in diallyl disulfide (DADS)-induced G2/M arrest in human gastric cancer MGC803 cells.
METHODS: MGC803 cell growth inhibition was measured by MTT assay. Phase distribution of cell cycle was analyzed by flow cytometry. Expression of Cdc25C, p38, phosphorylation of p38 (pp38) were determined by Western blotting.
RESULTS: MTT assay showed that SB203580, a specific p38 MAPK inhibitor blocked DADS-induced growth inhibition. Flow cytometry analysis revealed that treatment of MGC803 cells with 30 mg/L DADS increased the percentage of cells in the G2/M phase from 9.3% to 39.4% (P < 0.05), whereas inhibition of p38 activity by SB203580 abolished induction of G2/M arrest by DADS. Western blotting showed that phosphorylation of p38 was increased 3.52-fold following treatment of MGC803 cells with 30 mg/L DADS for 20 min (P < 0.05), whereas Cdc25C was decreased 68% following treatment of MGC803 cells with 30 mg/L DADS for 24 h (P < 0.05). Decreased Cdc25C protein expression by DADS was attenuated by SB203580 (P < 0.05).
CONCLUSION: DADS-induced G2/M arrest of MGC803 cells involves activation of p38 MAP kinase pathways. Decreased Cdc25C protein expression by p38 MAPK played a crucial role in G2/M arrest after treatment with DADS.
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Affiliation(s)
- Jing-Ping Yuan
- Department of Pathology, Central Hospital of Wuhan, Wuhan 430014, Hubei Province, China
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40
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Abstract
Tumor cell targeted therapies, by induction or enhancement of apoptosis, constitute recent promising approaches achieving more specific anti-tumor efficacy. The peripheral benzodiazepine receptor (PBR), which belongs to the permeability transition pore (PTP), the central regulatory complex of apoptosis, is a potential target. A number of findings argue in favor of the development of PBR targeting approaches: (i) overexpression of PBR has been described in a large range of human cancers, (ii) PTP-mediated regulation of programmed cell death is an apoptotic-inducing factor-independent check-point that could be modulated by various conventional cancer therapies, and (iii) PBR ligation enhances apoptosis induction in many types of tumors and reverses Bcl-2 cytoprotective effects. Altogether, these observations support the use of PBR-directed drugs, particularly PBR ligands such as Ro5-4864, in the treatment of human cancers.
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Affiliation(s)
- Didier Decaudin
- Department of Clinical Hematology, Institut Curie, Paris, France.
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Mak SK, Kültz D. Gadd45 Proteins Induce G2/M Arrest and Modulate Apoptosis in Kidney Cells Exposed to Hyperosmotic Stress. J Biol Chem 2004; 279:39075-84. [PMID: 15262964 DOI: 10.1074/jbc.m406643200] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Gadd45 proteins are induced by hyperosmolality in renal inner medullary (IM) cells, but their role for cell adaptation to osmotic stress is not known. We show that a cell line derived from murine renal IM cells responds to moderate hyperosmotic stress (540 mosmol/kg) by activation of G(2)/M arrest without significant apoptosis. If the severity of hyperosmotic stress exceeds the tolerance limit of this cell line (620 mosmol/kg) apoptosis is strongly induced. Using transient overexpression of ectopic Gadd45 proteins and simultaneous analysis of transfected versus non-transfected cells by laser-scanning cytometry, we were able to measure the effects of Gadd45 super-induction during hyperosmolality on G(2)/M arrest and apoptosis. Our results demonstrate that induction of all three Gadd45 isoforms inhibits mitosis and promotes G(2)/M arrest during moderate hyperosmotic stress but not in isosmotic controls. Furthermore, all three Gadd45 proteins are also involved in control of apoptosis during severe hyperosmotic stress. Under these conditions Gadd45gamma induction strongly potentiates apoptosis. In contrast, Gadd45alpha/beta induction transiently increases caspase 3/7 and annexin V binding before 12 h but inhibits later stages of apoptosis during severe hyperosmolality. These results show that Gadd45 isoforms function in common but also in distinct pathways during hyperosmolality and that their increased abundance contributes to the low mitotic index and protection of genomic integrity in cells of the mammalian renal inner medulla.
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Affiliation(s)
- Sally K Mak
- Physiological Genomics Group, Department of Animal Sciences, University of California, Davis, California 95616, USA
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Williamson AJK, Dibling BC, Boyne JR, Selby P, Burchill SA. Basic fibroblast growth factor-induced cell death is effected through sustained activation of p38MAPK and up-regulation of the death receptor p75NTR. J Biol Chem 2004; 279:47912-28. [PMID: 15310753 DOI: 10.1074/jbc.m409035200] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Basic fibroblast growth factor (bFGF) induces cell death in cells of the Ewing's sarcoma family of tumors in vivo and in vitro. In this study we demonstrate that this is dependent on the rapid and sustained activation of p38(MAPK), in contrast to the transient activation of p38(MAPK) associated with bFGF-induced cell proliferation. Stem cell factor-induced survival of TC-32 cells was also associated with transient activation of p38(MAPK). Inhibition of p38(MAPK) by SB202190 and p38(MAPK) small interfering RNA reduces bFGF-induced death in TC-32 cells, consistent with the hypothesis that activation of p38(MAPK) is essential for induction of death by bFGF. This appears to be dependent on sustained activation of p38(MAPK), demonstrated by inhibition of bFGF-induced cell death following addition of SB202190 to TC-32 cells 5 min after exposure to bFGF (20 ng/ml) and activation of p38(MAPK). Prolonged activation of p38(MAPK) is accompanied by a rapid and sustained phosphorylation of Ras and ERK; inhibition of ERK phosphorylation using the MEK-1 inhibitor PD98059 rescued approximately 30% of cells from bFGF-induced death suggesting ERK plays a secondary role in the induction of death. This hypothesis is supported by observations in the A673 cell line; bFGF induced sustained activation of ERK and transient activation of p38(MAPK), which was not associated with cell death. These data demonstrate that sustained activation of p38(MAPK) is essential for activation of the death cascade following exposure of Ewing's sarcoma family of tumors cells to bFGF and provide evidence that activation of p38(MAPK) results in an up-regulation of the death receptor p75(NTR).
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Affiliation(s)
- Andrew J K Williamson
- Candlelighter's Children's Cancer Research Laboratory, Cancer Research UK Clinical Centre, St. James's University Hospital, Leeds LS9 7TF, United Kingdom
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Chelli B, Lena A, Vanacore R, Da Pozzo E, Costa B, Rossi L, Salvetti A, Scatena F, Ceruti S, Abbracchio MP, Gremigni V, Martini C. Peripheral benzodiazepine receptor ligands: mitochondrial transmembrane potential depolarization and apoptosis induction in rat C6 glioma cells. Biochem Pharmacol 2004; 68:125-34. [PMID: 15183124 DOI: 10.1016/j.bcp.2004.03.008] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2003] [Accepted: 03/05/2004] [Indexed: 10/26/2022]
Abstract
The peripheral benzodiazepine receptor (PBR) is a component of a multiprotein complex, located at the contact site between the inner and outer mitochondrial membranes, which constitutes the mitochondrial permeability transition (MPT)-pore. The opening of the MPT-pore, leading to the transmembrane mitochondrial potential (DeltaPsi(m)) dissipation, is a critical event in the mechanism of apoptosis. In the present work, we investigated the ability of the specific PBR ligands, PK 11195 or Ro5-4864, to affect mitochondrial potential and to induce apoptotic cell death in rat C6 glioma cells. Both specific ligands inhibited cell survival in a dose- and time-dependent manner, as assessed by MTS conversion assay, whereas the non-site selective ligand Diazepam or the low-affinity benzodiazepine Clonazepam showed no significant effects. After cell exposure to PK 11195 or Ro5-4864 we evidenced typical alterations of apoptotic cell death such as DNA fragmentation and chromatin condensation assessed by flow cytometric and transmission electron microscopy (TEM) analysis, respectively. Activation of the "effector" caspase-3 confirmed the ability of specific PBR ligands to induce apoptosis. Moreover, PK 11195 and Ro5-4864 induced a decrease of DeltaPsi(m), as evidenced by JC-1 flow cytometry analysis. Our data demonstrate the pro-apoptotic effects of specific PBR ligands on rat C6 glioma cells.
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Affiliation(s)
- Beatrice Chelli
- Department of Psychiatry, Neurobiology, Pharmacology and Biotechnology, University of Pisa, Pisa, Italy
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Höpfner M, Sutter AP, Huether A, Ahnert-Hilger G, Scherübl H. A novel approach in the treatment of neuroendocrine gastrointestinal tumors: additive antiproliferative effects of interferon-gamma and meta-iodobenzylguanidine. BMC Cancer 2004; 4:23. [PMID: 15154969 PMCID: PMC442128 DOI: 10.1186/1471-2407-4-23] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2003] [Accepted: 05/21/2004] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Therapeutic options to effectively inhibit growth and spread of neuroendocrine gastrointestinal tumors are still limited. As both meta-iodobenzylguanidine (MIBG) and interferon-gamma (IFNgamma) cause antineoplastic effects in neuroendocrine gastrointestinal tumor cells, we investigated the antiproliferative effects of the combination of IFNgamma and non-radiolabeled MIBG in neuroendocrine gut STC-1 and pancreatic carcinoid BON tumor cells. METHODS AND RESULTS IFNgamma receptors were expressed in both models. IFNgamma dose- and time-dependently inhibited the growth of both STC-1 and of BON tumor cells with IC50-values of 95 +/- 15 U/ml and 135 +/- 10 U/ml, respectively. Above 10 U/ml IFNgamma induced apoptosis-specific caspase-3 activity in a time-dependent manner in either cell line and caused a dose-dependent arrest in the S-phase of the cell cycle. Furthermore, IFNgamma induced cytotoxic effects in NE tumor cells. The NE tumor-targeted drug MIBG is selectively taken up via norepinephrine transporters, thereby specifically inhibiting growth in NE tumor cells. Intriguingly, IFNgamma treatment induced an upregulation of norepinephrine transporter expression in neuroendocrine tumors cells, as determined by semi-quantitative RT-PCR. Co-application of sub-IC50 concentrations of IFNgamma and MIBG led to additive growth inhibitory effects, which were mainly due to increased cytotoxicity and S-phase arrest of the cell cycle. CONCLUSION Our data show that IFNgamma exerts antiproliferative effects on neuroendocrine gastrointestinal tumor cells by inducing cell cycle arrest, apoptosis and cytotoxicity. The combination of IFNgamma with the NE tumor-targeted agent MIBG leads to effective growth control at reduced doses of either drug. Thus, the administration of IFNgamma alone and more so, in combination with MIBG, is a promising novel approach in the treatment of neuroendocrine gastrointestinal tumors.
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Affiliation(s)
- Michael Höpfner
- Charité – Universitätsmedizin Berlin, Campus Benjamin Franklin, Medical Clinic I, Hindenburgdamm 30, 12200 Berlin, Germany
| | - Andreas P Sutter
- Charité – Universitätsmedizin Berlin, Campus Benjamin Franklin, Medical Clinic I, Hindenburgdamm 30, 12200 Berlin, Germany
| | - Alexander Huether
- Charité – Universitätsmedizin Berlin, Campus Benjamin Franklin, Medical Clinic I, Hindenburgdamm 30, 12200 Berlin, Germany
| | - Gudrun Ahnert-Hilger
- Charité – Universitätsmedizin Berlin, Campus Mitte, Institut für Anatomie, Philippstrasse 12, 10115 Berlin, Germany
| | - Hans Scherübl
- Charité – Universitätsmedizin Berlin, Campus Mitte, Institut für Anatomie, Philippstrasse 12, 10115 Berlin, Germany
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Sutter AP, Maaser K, Gerst B, Krahn A, Zeitz M, Scherübl H. Enhancement of peripheral benzodiazepine receptor ligand-induced apoptosis and cell cycle arrest of esophageal cancer cells by simultaneous inhibition of MAPK/ERK kinase. Biochem Pharmacol 2004; 67:1701-10. [PMID: 15081869 DOI: 10.1016/j.bcp.2004.01.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2003] [Accepted: 01/05/2004] [Indexed: 11/16/2022]
Abstract
Specific ligands of the peripheral benzodiazepine receptor (PBR) activate pro-apoptotic and anti-proliferative signaling pathways. Previously, we found that PBR ligands activated the p38 mitogen-activated protein kinase (MAPK) pathway in esophageal cancer cells, and that the activation of p38MAPK contributed to tumor cell apoptosis and cell cycle arrest. Here, we report that PBR ligands also activate the pro-survival MAPK/ERK kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway in esophageal cancer cells, which might compromise the efficacy of PBR ligands. Hence, a combination treatment of PBR ligands and MEK inhibitors, which are emerging as promising anticancer agents, was pursued to determine whether this treatment could lead to enhanced apoptosis and cell cycle arrest. Using Western blotting we demonstrated a time- and dose-dependent phosphorylation of ERK1/2 in response to PBR ligands. Apoptosis was investigated by assessment of mitochondrial alterations and caspase-3 activity. Cell cycle arrest was measured by flow cytometric analysis of stained isolated nuclei. The inhibition of MEK/ERK with a pharmacologic inhibitor, 2'-amino-3'-methoxyflavone (PD 98059), resulted in a synergistic enhancement of PBR-ligand-induced growth inhibition, apoptosis and cell cycle arrest. Specifity of the pharmacologic inhibitor was confirmed by the use of 1,4-diamino-2,3-dicyano-1,4-bis(2-aminophenylthio)butadiene (U 0126), a second MEK/ERK inhibitor, and 1,4-diamino-2,3-dicyano-1,4-bis(methylthio)butadiene (U 0124), a structural analogue of it which does not display any affinity to MEK. Enhanced pro-apoptotic and anti-proliferative effects were observed both in KYSE-140 esophageal squamous cancer and OE-33 adenocarcinoma cells, suggesting that this effect was not cell-type specific. In addition, the PBR-mediated overexpression of the stress response gene (growth arrest and DNA-damage-inducible gene gadd153) was synergistically enhanced by MEK inhibition. This is the first report of enhanced PBR-ligand-mediated apoptosis and cell cycle arrest by simultaneous MEK inhibition, suggesting a new anticancer strategy.
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Affiliation(s)
- Andreas P Sutter
- Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, Medical Clinic I, Berlin, Germany
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