1
|
Yao Q, Zhang H, Standish C, Grube J, Mañas A, Xiang J. Expression profile of the proapoptotic protein Bax in the human brain. Histochem Cell Biol 2023; 159:209-220. [PMID: 35951115 DOI: 10.1007/s00418-022-02146-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/27/2022] [Indexed: 11/27/2022]
Abstract
Bax is a well-known universal proapoptotic protein. Bax protein is detected in almost all human organs, and its expression levels can be correlated with disease progression and therapeutic efficacy in certain settings. Interestingly, increasing evidence has shown that mature neuronal cell death is often not typical apoptosis. Most results on the expression of Bax proteins (predominantly Baxα) in the human brain come from disease-oriented studies, and the data on Bax protein expression in the normal brain are limited and lack consistency due to many variable factors. Here, we analyzed Bax RNA and protein expression data from multiple databases and performed immunostaining of over 80 samples from 25 healthy subjects across 7 different brain regions. We found that Bax protein expression was heterogeneous across brain regions and individual subjects. Both neurons and glial cells, such as astrocytes, could be Bax positive, but Bax positivity appeared to be highly selective, even within the same cell type in the same region. Furthermore, Bax proteins could be localized in the cytosol (evenly spread or concentrated to one region), nucleus or nucleolus depending on the cell type. Such variation and distribution in Bax expression suggest that Bax may function differently in the human brain than in other organs.
Collapse
Affiliation(s)
- Qi Yao
- Department of Biology, Lewis College of Science and Letters, Illinois Institute of Technology, 3101 South Dearborn Street, Chicago, IL, 60616, USA
| | - Huaiyuan Zhang
- Department of Biology, Lewis College of Science and Letters, Illinois Institute of Technology, 3101 South Dearborn Street, Chicago, IL, 60616, USA
| | - Collin Standish
- Department of Biology, Lewis College of Science and Letters, Illinois Institute of Technology, 3101 South Dearborn Street, Chicago, IL, 60616, USA
| | - Joshua Grube
- Department of Biology, Lewis College of Science and Letters, Illinois Institute of Technology, 3101 South Dearborn Street, Chicago, IL, 60616, USA
| | - Adriana Mañas
- Department of Biology, Lewis College of Science and Letters, Illinois Institute of Technology, 3101 South Dearborn Street, Chicago, IL, 60616, USA
| | - Jialing Xiang
- Department of Biology, Lewis College of Science and Letters, Illinois Institute of Technology, 3101 South Dearborn Street, Chicago, IL, 60616, USA.
| |
Collapse
|
2
|
Saquib Q, Xia P, Siddiqui MA, Zhang J, Xie Y, Faisal M, Ansari SM, Alwathnani HA, Alatar AA, Al-Khedhairy AA, Zhang X. High-throughput transcriptomics: An insight on the pathways affected in HepG2 cells exposed to nickel oxide nanoparticles. CHEMOSPHERE 2020; 244:125488. [PMID: 31812053 DOI: 10.1016/j.chemosphere.2019.125488] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 11/24/2019] [Accepted: 11/26/2019] [Indexed: 06/10/2023]
Abstract
Nickel oxide nanoparticles (NiO-NPs) have been used in several consumer goods, reported to demonstrate the hepatotoxic effects in vitro and in vivo test models. Nonetheless the molecular mechanism of hepatotoxicity is still missing. Hence, a toxicogenomic approach integrating microscopic techniques and high-throughput RNA sequencing (RNA-Seq) was applied to reveal hepatotoxicity in human hepatocellular carcinoma cells (HepG2). NiO-NPs induced a concentration dependent (5-100 μg/ml) cytotoxicity, with a No observed effect level (NOEL) of 5 μg/ml. Hypoxia-inducible transcription factor-1α (HIF-1α) and miR-210 microRNA were upregulated at 25 and 100 μg/ml, while significant alteration on transcriptome at mRNA and pathway level was observed at non-toxic level of NiO-NPs treatment. The treated cells also showed activation of glycolysis, glutathione, lysosomes and autophagy pathways by a pathway-driven analysis. Flow cytometric analysis affirmed the elevation in nitric oxide (NO), Ca++ influx, esterase, and disruption of mitochondrial membrane potential (ΔΨm). Cell cycle dysregulation was affirmed by the appearance of 30.5% subG1 apoptotic peak in NiO-NPs (100 μg/ml) treated cells. The molecular responses were consistent with the microscopic observation that NiO-NPs induced subcellular alterations in HepG2 cells. We conclude that hypoxia stress played a pivotal role in NiO-NPs induced hepatoxicity in HepG2 cells. Concentration dependent effects on transcriptomics specify a powerful tool to evaluate the molecular mechanisms of nanoparticle induced cytotoxicity. Overall our study unequivocally affirmed the transcriptomic alterations in human cells, consequently the prevalent usage of NiO-NPs should be given subtle consideration owing to its effects on biological processes.
Collapse
Affiliation(s)
- Quaiser Saquib
- Zoology Department, College of Sciences, King Saud University, P.O. Box 2455, Riyadh, 11451, Saudi Arabia; A.R. Al-Jeraisy Chair for DNA Research, Zoology Department, College of Sciences, King Saud University, P.O. Box 2455, Riyadh, 11451, Saudi Arabia
| | - Pu Xia
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - Maqsood A Siddiqui
- A.R. Al-Jeraisy Chair for DNA Research, Zoology Department, College of Sciences, King Saud University, P.O. Box 2455, Riyadh, 11451, Saudi Arabia
| | - Junjiang Zhang
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - Yuwei Xie
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - Mohammad Faisal
- Department of Botany & Microbiology, College of Sciences, King Saud University, P.O Box 2455, Riyadh, 11451, Saudi Arabia
| | - Sabiha M Ansari
- Department of Botany & Microbiology, College of Sciences, King Saud University, P.O Box 2455, Riyadh, 11451, Saudi Arabia
| | - Hend A Alwathnani
- Department of Botany & Microbiology, College of Sciences, King Saud University, P.O Box 2455, Riyadh, 11451, Saudi Arabia
| | - Abdulrahman A Alatar
- Department of Botany & Microbiology, College of Sciences, King Saud University, P.O Box 2455, Riyadh, 11451, Saudi Arabia
| | - Abdulaziz A Al-Khedhairy
- Zoology Department, College of Sciences, King Saud University, P.O. Box 2455, Riyadh, 11451, Saudi Arabia
| | - Xiaowei Zhang
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China.
| |
Collapse
|
3
|
McConnell DD, Carr SB, Litofsky NS. Potential effects of nicotine on glioblastoma and chemoradiotherapy: a review. Expert Rev Neurother 2019; 19:545-555. [PMID: 31092064 DOI: 10.1080/14737175.2019.1617701] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Introduction: Glioblastoma multiforme (GBM) has a poor prognosis despite maximal surgical resection with subsequent multi-modal radiation and chemotherapy. Use of tobacco products following diagnosis and during the period of treatment for non-neural tumors detrimentally affects treatment and prognosis. Approximately, 16-28% of patients with glioblastoma continue to smoke after diagnosis and during treatment. The literature is sparse for information-pertaining effects of smoking and nicotine on GBM treatment and prognosis. Areas covered: This review discusses cellular pathways involved in GBM progression that might be affected by nicotine, as well as how nicotine may contribute to resistance to treatment. Similarities of GBM pathways to those in non-neural tumors are investigated for potential effects by nicotine. English language papers were identified using PubMed, Medline and Scopus databases using a combination of keywords including but not limited to the following: nicotine, vaping, tobacco, e-cigarettes, smoking, vaping AND glioblastoma or brain cancer OR/AND temozolomide, carmustine, methotrexate, procarbazine, lomustine, vincristine, and neural tumor cell lines. Expert opinion: Understanding the impact of nicotine on treatment and resistance to chemotherapeutics should allow physicians to educate their patients with GBM with evidence-based recommendations about the effects of continuing to use nicotine-containing products after diagnosis and during treatment.
Collapse
Affiliation(s)
- Diane D McConnell
- a Division of Neurological Surgery , University of Missouri School of Medicine , Columbia , MO , USA
| | - Steven B Carr
- a Division of Neurological Surgery , University of Missouri School of Medicine , Columbia , MO , USA
| | - N Scott Litofsky
- a Division of Neurological Surgery , University of Missouri School of Medicine , Columbia , MO , USA
| |
Collapse
|
4
|
Abstract
B-cell lymphoma 2 (BCL-2) family proteins gather at the biologic cross-roads of renal cell survival: the outer mitochondrial membrane. Despite shared sequence and structural features, members of this conserved protein family constantly antagonize each other in a life-and-death battle. BCL-2 members innocently reside within renal cells until activated or de-activated by physiologic stresses caused by common nephrotoxins, transient ischemia, or acute glomerulonephritis. Recent experimental data not only illuminate the intricate mechanisms of apoptosis, the most familiar form of BCL-2-mediated cell death, but emphasizes their newfound roles in necrosis, necroptosis, membrane pore transition regulated necrosis, and other forms of acute cell demise. A major paradigm shift in non-cell death roles of the BCL-2 family has occurred. BCL-2 proteins also regulate critical daily renal cell housekeeping functions including cell metabolism, autophagy (an effective means for recycling cell components), mitochondrial morphology (organelle fission and fusion), as well as mitochondrial biogenesis. This article considers new concepts in the biochemical and structural regulation of BCL-2 proteins that contribute to membrane pore permeabilization, a universal feature of cell death. Despite these advances, persistent BCL-2 family mysteries continue to challenge cell biologists. Given their interface with many intracellular functions, it is likely that BCL-2 proteins determine cell viability under many pathologic circumstances relevant to the nephrologist and, as a consequence, represent an ideal therapeutic target.
Collapse
Affiliation(s)
- Steven C Borkan
- Evans Biomedical Research Center, Boston University Medical Center, Boston, MA.
| |
Collapse
|
5
|
Kim SJ, Hwang E, Yi SS, Song KD, Lee HK, Heo TH, Park SK, Jung YJ, Jun HS. Sea Buckthorn Leaf Extract Inhibits Glioma Cell Growth by Reducing Reactive Oxygen Species and Promoting Apoptosis. Appl Biochem Biotechnol 2017; 182:1663-1674. [PMID: 28181191 DOI: 10.1007/s12010-017-2425-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 01/24/2017] [Indexed: 02/07/2023]
Abstract
Hippophae rhamnoides L., also known as sea buckthorn (SBT), possesses a wide range of biological and pharmacological activities. However, the underlying mechanism is largely unknown. The present study examined whether SBT leaf extract could inhibit proliferation and promote apoptosis of rat glioma C6 cells. The results revealed that the treatment with SBT leaf extract inhibited proliferation of rat C6 glioma cells in a dose-dependent manner. SBT-induced reduction of C6 glioma cell proliferation and viability was accompanied by a decrease in production of reactive oxygen species (ROS), which are critical for the proliferation of tumor cells. SBT treatment not only significantly upregulated the expression of the pro-apoptotic protein Bcl-2-associated X (Bax) but also promoted its localization in the nucleus. Although increased expression and nuclear translocation of Bax were observed in SBT-treated C6 glioma cells, the induced nuclear morphological change was distinct from that of typical apoptotic cells in that most of SBT-treated cells were characterized by convoluted nuclei with cavitations and clumps of chromatin. All of these results suggest that SBT leaf extract could inhibit the rapid proliferation of rat C6 glioma cells, possibly by inducing the early events of apoptosis. Thus, SBT may serve as a potential therapeutic candidate for the treatment of glioma.
Collapse
Affiliation(s)
- Sung-Jo Kim
- Department of Biotechnology, Hoseo University, 165, Baebang, Asan, Chungnam, 31499, Republic of Korea
| | - Eunmi Hwang
- Department of Biotechnology, Hoseo University, 165, Baebang, Asan, Chungnam, 31499, Republic of Korea
| | - Sun Shin Yi
- Department of Biomedical Laboratory Science, College of Biomedical Sciences, Soonchunhyang University, Asan, 31538, Republic of Korea
| | - Ki Duk Song
- Department of Animal Biotechnology, Chonbuk National University, Jeonju, 54896, Republic of Korea
| | - Hak-Kyo Lee
- Department of Animal Biotechnology, Chonbuk National University, Jeonju, 54896, Republic of Korea
| | - Tae-Hwe Heo
- Laboratory of Immunology, Integrated Research Institute of Pharmaceutical Sciences, College of Pharmacy, The Catholic University of Korea, Bucheon, 14662, Republic of Korea
| | - Sang-Kyu Park
- Department of Medical Biotechnology, College of Medical Sciences, Soonchunhyang University, Asan, 31538, Republic of Korea
| | - Yun Joo Jung
- Corea Cosmedical Center, 3-103, 38, Wolgok-gil, Gangnae-myeon, Heungdeok-gu, Cheongju-si, Chungcheongbuk-do, 28171, Republic of Korea.
| | - Hyun Sik Jun
- Department of Biotechnology and Bioinformatics, College of Science and Technology, Korea University, Sejong, 30019, Republic of Korea.
| |
Collapse
|
6
|
Xie Q, Yan Y, Huang Z, Zhong X, Huang L. MicroRNA-221 targeting PI3-K/Akt signaling axis induces cell proliferation and BCNU resistance in human glioblastoma. Neuropathology 2014; 34:455-64. [PMID: 24780067 DOI: 10.1111/neup.12129] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 04/10/2014] [Indexed: 01/10/2023]
Abstract
MicroRNAs (miRNAs) are short regulatory RNAs that negatively regulate protein biosynthesis at the post-transcriptional level and participate in the pathogenesis of different types of human cancers, including glioblastoma. In particular, the levels of miRNA-221 are overexpressed in many cancers and miRNA-221 exerts its functions as an oncogene. Nevertheless, the roles of miRNA-221 in carmustine (BCNU)-resistant glioma cells have not been totally elucidated. In the present study, we explored the effects of miRNA-221 on BCNU-resistant glioma cells and the possible molecular mechanisms by which miRNA-221 mediated the cell proliferation, survival, apoptosis and BCNU resistance were investigated. We found that miR-221 was overexpressed in glioma cells, including BCNU-resistant cells. Moreover, we found that miR-221 regulated cell proliferation and BCNU resistance in glioma cells. Overexpression of miR-221 led to cell survival and BCNU resistance and reduced cell apoptosis induced by BCNU, whereas knockdown of miR-221 inhibited cell proliferation and prompted BCNU sensitivity and cell apoptosis. Further investigation revealed that miR-221 down-regulated PTEN and activated Akt, which resulted in cell survival and BCNU resistance. Overexpression of PTEN lacking 3'UTR or PI3-K/Akt specific inhibitor wortmannin attenuated miR-221-mediated BCNU resistance and prompted cell apoptosis. We propose that miR-221 regulated cell proliferation and BCNU resistance in glioma cells by targeting PI3-K/PTEN/Akt signaling axis. Our findings may provide a new potential therapeutic target for treatment of glioblastoma.
Collapse
Affiliation(s)
- Qiang Xie
- Department of Oncology, Armed Police Corps Hospital, Guangzhou, China; Department of Pathology, School of Medicine, Jinan University, Guangzhou, China
| | | | | | | | | |
Collapse
|
7
|
Lindenboim L, Borner C, Stein R. Nuclear proteins acting on mitochondria. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2010; 1813:584-96. [PMID: 21130123 DOI: 10.1016/j.bbamcr.2010.11.016] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2010] [Revised: 11/08/2010] [Accepted: 11/23/2010] [Indexed: 12/23/2022]
Abstract
An important mechanism in apoptotic regulation is changes in the subcellular distribution of pro- and anti-apoptotic proteins. Among the proteins that change in their localization and may promote apoptosis are nuclear proteins. Several of these nuclear proteins such as p53, Nur77, histone H1.2, and nucleophosmin were reported to accumulate in the cytosol and/or mitochondria and to promote the mitochondrial apoptotic pathway in response to apoptotic stressors. In this review, we will discuss the functions of these and other nuclear proteins in promoting the mitochondrial apoptotic pathway, the mechanisms that regulate their accumulation in the cytosol and/or mitochondria and the potential role of Bax and Bak in this process. This article is part of a Special Issue entitled Mitochondria: the deadly organelle.
Collapse
Affiliation(s)
- Liora Lindenboim
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Tel Aviv University, 69978 Ramat Aviv, Israel
| | | | | |
Collapse
|
8
|
Bim nuclear translocation and inactivation by viral interferon regulatory factor. PLoS Pathog 2010; 6:e1001031. [PMID: 20700448 PMCID: PMC2916877 DOI: 10.1371/journal.ppat.1001031] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2010] [Accepted: 07/08/2010] [Indexed: 11/19/2022] Open
Abstract
Viral replication efficiency is in large part governed by the ability of viruses to counteract pro-apoptotic signals induced by infection of the host cell. Human herpesvirus 8 (HHV-8) uses several strategies to block the host's innate antiviral defenses via interference with interferon and apoptotic signaling. Contributors include the four viral interferon regulatory factors (vIRFs 1–4), which function in dominant negative fashion to block cellular IRF activities in addition to targeting IRF signaling-induced proteins such as p53 and inhibiting other inducers of apoptosis such as TGFβ receptor-activated Smad transcription factors. Here we identify direct targeting by vIRF-1 of BH3-only pro-apoptotic Bcl-2 family member Bim, a key negative regulator of HHV-8 replication, to effect its inactivation via nuclear translocation. vIRF-1-mediated relocalization of Bim was identified in transfected cells, by both immunofluorescence assay and western analysis of fractionated cell extracts. Also, co-localization of vIRF-1 and Bim was detected in nuclei of lytically infected endothelial cells. In vitro co-precipitation assays using purified vIRF-1 and Bim revealed direct interaction between the proteins, and Bim-binding residues of vIRF-1 were mapped by deletion and point mutagenesis. Generation and experimental utilization of Bim-refractory vIRF-1 variants revealed the importance of vIRF-1:Bim interaction, specifically, in pro-replication and anti-apoptotic activity of vIRF-1. Furthermore, blocking of the interaction with cell-permeable peptide corresponding to the Bim-binding region of vIRF-1 confirmed the relevance of vIRF-1:Bim association to vIRF-1 pro-replication activity. To our knowledge, this is the first report of an IRF protein that interacts with a Bcl-2 family member and of nuclear sequestration of Bim or any other member of the family as a means of inactivation. The data presented reveal a novel mechanism utilized by a virus to control replication-induced apoptosis and suggest that inhibitory targeting of vIRF-1:Bim interaction may provide an effective antiviral strategy. Human herpesvirus 8 (HHV-8) is a pathogen associated with cancers Kaposi's sarcoma (KS), an endothelial cell disease, and B cell malignancies primary effusion lymphoma and multicentric Castleman's disease. KS is particularly prevalent amongst HIV-positive populations in Africa and is a major health concern. Virus productive replication, in addition to latency, is important for maintaining viral load within the host and also for KS pathogenesis. Essential to HHV-8 and other virus replication is the control of innate host defenses, which comprise stress-sensing cellular signaling pathways that result ultimately in programmed cell death (apoptosis). Here we identify a novel mechanism whereby a viral protein, viral interferon regulatory factor-1 (vIRF-1), mediates inhibition of a stress sensor and initiator of apoptosis, Bim, by inducing its translocation to the cell nucleus and thereby sequestration away from the cytoplasmic compartment where it exerts its pro-death activity. We show that vIRF-1:Bim interaction is necessary for efficient HHV-8 productive replication and that it can be blocked using a cell-permeable antagonist of vIRF-1:Bim binding. Our data not only identify previously unsuspected mechanisms of Bim inactivation and vIRF-1 function, but suggest that inhibitory targeting of vIRF-1 interaction with Bim may be of therapeutic benefit.
Collapse
|
9
|
Schor NF. Pharmacotherapy for adults with tumors of the central nervous system. Pharmacol Ther 2008; 121:253-64. [PMID: 19091301 DOI: 10.1016/j.pharmthera.2008.11.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2008] [Accepted: 11/07/2008] [Indexed: 11/18/2022]
Abstract
Tumors of the adult central nervous system are among the most common and most chemoresistant neoplasms. Malignant tumors of the brain and spinal cord collectively account for approximately 1.3% of all cancers and 2.2% of all cancer-related deaths. Novel pharmacological approaches to nervous system tumors are urgently needed. This review presents the current approaches and challenges to successful pharmacotherapy of adults with malignant tumors of the central nervous system and discusses novel approaches aimed at overcoming these challenges.
Collapse
Affiliation(s)
- Nina F Schor
- Departments of Pediatrics, Neurology, and Neurobiology & Anatomy, University of Rochester Medical Center, Rochester, NY, USA.
| |
Collapse
|
10
|
Schepkin VD, Lee KC, Kuszpit K, Muthuswami M, Johnson TD, Chenevert TL, Rehemtulla A, Ross BD. Proton and sodium MRI assessment of emerging tumor chemotherapeutic resistance. NMR IN BIOMEDICINE 2006; 19:1035-42. [PMID: 16894643 PMCID: PMC3140794 DOI: 10.1002/nbm.1074] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The ultimate goal of any cancer therapy is to target the elimination of neoplastic cells. Although newer therapeutic strategies are in constant development, therapeutic assessment has been hampered by the inability to assess, rapidly and quantitatively, efficacy in vivo. Diffusion imaging and, more recently, sodium MRI have demonstrated their distinct abilities to detect therapy-induced alterations in tumor cellularity, which has been demonstrated to be indicative of therapeutic efficacy. More importantly, both imaging modalities detect tumor response much earlier than traditional methodologies that rely on macroscopic volumetric changes. In this study, the correlation between tumor sodium and diffusion was further tested to demonstrate the sensitivity of sodium imaging to gauge tumor response to therapy by using a 9L rat gliosarcoma treated with varying doses of BCNU [1,3-bis(2-chloroethyl)-1-nitrosourea]. This orthotopic model has been demonstrated to display variability in response to BCNU therapy where initial insult has been shown to lead to drug-resistance. In brief, a single 26.6 mg/kg BCNU dose yielded dramatic responses in both diffusion and sodium MRI. However, a second equivalent BCNU dose yielded a much smaller change in diffusion and sodium, suggesting a drop in tumor sensitivity to BCNU. The MRI responses of animals treated with 13.3 mg/kg BCNU were much lower and similar responses were observed after the initial and secondary applications of BCNU. Furthermore, these results were further validated using volumetric measurements of the tumor and also ex vivo determination of tumor sensitivity to BCNU. Overall, these experiments demonstrate the sensitivity and applicability of sodium and diffusion MRI as tools for dynamic assessment of tumor response to therapy.
Collapse
Affiliation(s)
- Victor D. Schepkin
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA
- Department of Radiology, Center for Molecular Imaging, University of Michigan Medical School, Ann Arbor, MI 48109-0503, USA
| | - Kuei C. Lee
- Department of Radiology, Center for Molecular Imaging, University of Michigan Medical School, Ann Arbor, MI 48109-0503, USA
| | - Kyle Kuszpit
- Department of Radiology, Center for Molecular Imaging, University of Michigan Medical School, Ann Arbor, MI 48109-0503, USA
| | - Mukilan Muthuswami
- Department of Radiology, Center for Molecular Imaging, University of Michigan Medical School, Ann Arbor, MI 48109-0503, USA
| | - Timothy D. Johnson
- Department of Biostatistics, Center for Molecular Imaging, University of Michigan Medical School, Ann Arbor, MI 48109-0503, USA
| | - Thomas L. Chenevert
- Department of Radiology, Center for Molecular Imaging, University of Michigan Medical School, Ann Arbor, MI 48109-0503, USA
| | - Alnawaz Rehemtulla
- Department of Radiology, Center for Molecular Imaging, University of Michigan Medical School, Ann Arbor, MI 48109-0503, USA
| | - Brian D. Ross
- Department of Radiology, Center for Molecular Imaging, University of Michigan Medical School, Ann Arbor, MI 48109-0503, USA
| |
Collapse
|
11
|
Borrego A, Zamora ZB, González R, Romay C, Menéndez S, Hernández F, Berlanga J, Montero T. Ozone/Oxygen Mixture Modifies the Subcellular Redistribution of Bax Protein in Renal Tissue from Rats Treated with Cisplatin. Arch Med Res 2006; 37:717-22. [PMID: 16824930 DOI: 10.1016/j.arcmed.2006.02.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2005] [Accepted: 02/24/2006] [Indexed: 11/27/2022]
Abstract
BACKGROUND Cellular events in cisplatin-mediated nephrotoxicity include apoptosis induction, decreased protein synthesis, changes in the subcellular redistribution of Bax mitochondrial dysfunction, DNA injury, increased lipid peroxidation, depletion of glutathione and decrease in enzymatic activity of renal antioxidant enzymes. In previous papers we have shown that intra-rectal (i.r.) ozone/oxygen mixture protected and induced a significant recovery in cisplatin-induced renal damage and was related to a significant increase in the antioxidant system in renal tissue. METHODS This study was undertaken to examine the effect of the ir applications of ozone/oxygen mixture in the renal expression pattern of Bax proteins in rats treated with cisplatin. A group of male Sprague-Dawley rats was pretreated with 15 i.r. applications of ozone/oxygen (1.1 mg/kg) before intraperitoneal injection of cisplatin (6 mg/kg). Another group was treated with five i.r. applications of ozone/oxygen mixture after cisplatin administration. Serum creatinine was measured thereafter. Subcellular distribution of Bax in renal tissue was analyzed by immunohistochemistry. RESULTS Ozone pretreatment prevented the increase in serum creatinine levels and completely inhibited the acute tubular necrosis induced by cisplatin in renal tissue, diminishing the expression of Bax. Ozone treatment after cisplatin application reduced the increase in serum creatinine levels and the renal necrosis, inducing a lesser decrease of the Bax expression in cisplatin-treated kidneys. CONCLUSIONS Expression of Bax in renal tissue seems to play an important role in the protection and recovery in cisplatin-nephrotoxicity achieved by ozone/oxygen mixture.
Collapse
Affiliation(s)
- Aluet Borrego
- National Laboratory for the Control of Drugs, Center for the Control and Development of Drugs, Havana, Cuba.
| | | | | | | | | | | | | | | |
Collapse
|
12
|
Newton HB. Molecular neuro-oncology and the development of targeted therapeutic strategies for brain tumors. Part 5: apoptosis and cell cycle. Expert Rev Anticancer Ther 2006; 5:355-78. [PMID: 15877531 DOI: 10.1586/14737140.5.2.355] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Brain tumors are a diverse group of malignancies that remain refractory to conventional treatment approaches. Molecular neuro-oncology has now begun to clarify the transformed phenotype of brain tumors and identify oncogenic pathways that might be amenable to targeted therapy. Abnormalities of the apoptotic and cell cycle signaling pathways are key molecular features of many brain tumors and are currently under evaluation for potential therapeutic intervention. The apoptosis pathway has numerous targets for molecular therapeutic development, including p53, Bax, Bcl-2, cFLIP, effector caspases, growth factor receptors, phosphatidylinositol-3-kinase, Akt and apoptosis inhibitors. Current molecular treatment approaches include antisense techniques, gene therapy and small-molecule modulators and inhibitors. Potential targets of the cell cycle pathway include the cyclins, cyclin-dependent kinases, p53, retinoblastoma, E2F and the cyclin-dependent kinase inhibitors. Developmental molecular therapeutics for this pathway include adenoviral and gene therapy, small-peptide cyclin-dependent kinase modulators, proteasomal inhibitors and small-molecule cyclin-dependent kinase inhibitors. Several of these recently identified agents have begun evaluation in clinical trials. Further development of targeted therapies designed to modulate apoptosis and the cell cycle, and evaluation of these new agents in clinical trials, will be needed to improve survival and quality of life for patients with brain tumors.
Collapse
Affiliation(s)
- Herbert B Newton
- Dardinger Neuro-Oncology Center, Department of Neurology, The Ohio State University Hospitals, 465 Means Hall, 1654 Upham Drive, Columbus, OH 43210, USA.
| |
Collapse
|
13
|
Schepkin VD, Ross BD, Chenevert TL, Rehemtulla A, Sharma S, Kumar M, Stojanovska J. Sodium magnetic resonance imaging of chemotherapeutic response in a rat glioma. Magn Reson Med 2005; 53:85-92. [PMID: 15690506 PMCID: PMC3121241 DOI: 10.1002/mrm.20332] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This study investigates the comparative changes in the sodium MRI signal and proton diffusion following treatment using a 9L rat glioma model to develop markers of earliest response to cancer therapy. Sodium MRI and proton diffusion mapping were performed on untreated (n = 5) and chemotherapy 1,3-bis(2-chloroethyl)-1-nitrosourea-treated rats (n = 5). Animals were scanned serially at 2- to 3-day intervals for up to 30 days following therapy. The time course of Na concentration in a tumor showed a dramatic increase in the treated brain tumor compared to the untreated tumor, which correlates in time with an increase in tumor water diffusion. The largest posttreatment increase in sodium signal occurred 7-9 days following treatment and correlated to the period of the greatest chemotherapy-induced cellular necrosis based on diffusion and histopathology. Both Na MRI and proton ADC mapping revealed early changes in tumor sodium content and cellularity. This study demonstrates the possibility of Na MRI to function as a biomarker for monitoring early tumor treatment and validates the use of monitoring changes in diffusion MRI values for assessing tumor cellularity.
Collapse
Affiliation(s)
- Victor D Schepkin
- Department of Radiology, Center for Molecular Imaging, University of Michigan Medical School, Kresge II Research Building, R3028, 200 Zina Pitcher Place, Ann Arbor, MI 48109, USA.
| | | | | | | | | | | | | |
Collapse
|
14
|
Kaufmann JA, Perez M, Zhang W, Bickford PC, Holmes DB, Taglialatela G. Free radical-dependent nuclear localization of Bcl-2 in the central nervous system of aged rats is not associated with Bcl-2-mediated protection from apoptosis. J Neurochem 2004; 87:981-94. [PMID: 14622128 DOI: 10.1046/j.1471-4159.2003.02092.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have previously reported that Bcl-2 is up-regulated in the CNS of aged F344 rats as a consequence of oxidative stress. In addition to increased levels of expression, we now report that there is a subcellular redistribution of Bcl-2 in the CNS of aged F344 rats. Using western blotting, we found Bcl-2 predominantly located in the cytosol of young rats. However, in aged rats Bcl-2 was found primarily in the nucleus. This distribution, in the hippocampus and cerebellum, was reversed by treatment with the nitrone spin trap N-tert-butyl-alpha-phenylnitrone (PBN). Paradoxically, PBN treatment in young rats had the opposite effect, changing Bcl-2 from predominantly cytosolic to nuclear. We also detected an increase in Bax in aged hippocampal samples (both nuclear and cytosolic), which was reversed by treatment with PBN. The distribution of Bcl-2 and Bax in the cytosol of aged rats dramatically decreased the Bcl-2/Bax ratio, a probable indicator of neuronal vulnerability, which was restored upon treatment with PBN. In order to assess the effect of nuclear association of Bcl-2 we used PC12 cells stably transfected with a Bcl-2 construct to which we added the nuclear localization sequence of the SV40 large T antigen to the N-terminus which resulted in nuclear targeting of Bcl-2. Measurement of cell death using lactate dehydrogenase assays showed that, contrary to wild-type Bcl-2, Bcl-2 localized to the nucleus was not effective in protecting cells from treatment with 250 microm H2O2. These results suggest that nuclear localization of Bcl-2 observed in the aged CNS may not reflect a protective mechanism against oxidative stress, a major component of age-associated CNS impairments.
Collapse
Affiliation(s)
- Joel A Kaufmann
- Department of Anatomy and Neurosciences, University of Texas Medical Branch at Galveston, Galveston, Texas 77555-1043, USA
| | | | | | | | | | | |
Collapse
|
15
|
Abstract
Betanodavirus greasy grouper (Epinephelus tauvina) nervous necrosis viruses (GGNNV) protein alpha, a virus capsid protein, was detected in both nucleolus and cytoplasm of infected cells of Asian sea bass (SB) and transfected cells of SB and Cos-7 with pcDNA3.1/RNA2. To study its subcellular localization, ORF of protein alpha with 338 aa was fused with enhanced green fluorescent protein (EGFP) gene and was detected in transfected cells in the absence of other viral proteins. In both SB and Cos-7 cells, protein alpha was found to localize EGFP to the nucleolus and cytoplasm. Deletion mutants of protein alpha indicated that N-terminal 43 amino acid residues were required to import EGFP-alpha protein into the nucleolus. Further deletions within the 43 amino acid backbone, EGFP/33aa(1-33) and EGFP/30aa(14-43), localized to the nucleolus, suggesting that the 20 amino acids from 14 to 33 of protein alpha were the domain of nucleolus localization. To further determine the nucleolus targeting sequence, deletion mutations within the 20 amino acids of protein alpha were constructed. It was found that the deletion of (23)RRR(25), (29)RRR(31), or (23)RRRANNRRR(31) prevented the accumulation of EGFP fusion proteins into the nucleolus, demonstrating that (23)RRRANNRRR(31) contain the signal required for nucleolar localization. A similar distribution pattern of localization of protein alpha and its deletion mutants in SB and Cos-7 cells suggested that N-terminal residues of protein alpha (23)RRRANNRRR(31) constitute a nucleolus localization signal that functions in both fish and mammalian cells.
Collapse
Affiliation(s)
- Yan Xiang Guo
- Temasek Life Sciences Laboratory, The National University of Singapore, 117604, Singapore
| | | | | |
Collapse
|
16
|
Colombaioni L, Colombini L, Garcia-Gil M. Role of mitochondria in serum withdrawal-induced apoptosis of immortalized neuronal precursors. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 2002; 134:93-102. [PMID: 11947940 DOI: 10.1016/s0165-3806(01)00326-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The intracellular mechanisms controlling apoptosis in immature neurons are still largely unknown. Taking immortalized hippocampal neuronal precursors (mouse cell line HN9.10e) as a model, we have analyzed the cellular events associated to apoptosis induced by serum deprivation. We observed translocation of Bax from cytosol to mitochondria after 1 h of serum withdrawal followed, 2 h later, by cytochrome c release from mitochondria. These events occurred without mitochondrial membrane potential loss nor mitochondrial calcium raise. As calcium is implicated in several cell death pathways, we analyzed intracellular calcium levels after longer periods of serum deprivation. After 6 h, an increase of cytosolic Ca2+ was detected in HN9.10e cells loaded with the Ca2+ indicator Fluo3-AM. This increase of calcium preceded morphological signs of apoptosis such as cell shrinkage and nuclear fragmentation, and was followed by a more pronounced raise that persisted until the terminal phases of the apoptotic process. Cells serum-deprived for 4 h and then grown in complete medium for 20 h fully recovered viability. Summarizing, in HN9.10e cells, calcium deregulation occurs in the late phases of apoptosis; earlier events involve translocation of Bax, release of cytochrome c, and maintenance of mitochondrial functionality. This allows an enlargement of the temporal window in which commitment to death is reversible.
Collapse
Affiliation(s)
- Laura Colombaioni
- Institute of Neurophysiology of CNR, Italian National Research Council, Area della Ricerca CNR, Via G. Moruzzi, 1, Pisa, Italy.
| | | | | |
Collapse
|
17
|
SAEKI K, MATSUMOTO T, TANABE K, AMANO T. Rapid discrimination of polyethylene grades by combining a near-infrared spectra measurement and a neural network analysis. BUNSEKI KAGAKU 2001. [DOI: 10.2116/bunsekikagaku.50.223] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|