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Nakayama S, Yoda E, Yamashita S, Takamatsu Y, Suzuki Y, Kondo Y, Hara S. Knockdown of iPLA 2γ enhances cisplatin-induced apoptosis by increasing ROS-dependent peroxidation of mitochondrial phospholipids in bladder cancer cells. Free Radic Biol Med 2024; 220:301-311. [PMID: 38734266 DOI: 10.1016/j.freeradbiomed.2024.05.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2024] [Revised: 05/02/2024] [Accepted: 05/08/2024] [Indexed: 05/13/2024]
Abstract
Cisplatin (CDDP) is a platinum-based drug with anti-cancer activity and is widely used as a standard therapy for bladder cancer. It is well known that CDDP causes cell death by increasing the generation of reactive oxygen species (ROS) and lipid peroxidation, but the mechanism of its anti-cancer effects has not been fully elucidated. There are still some problems such as chemoresistance in CDDP therapy. In the present study, we found the expression of Ca2+-independent phospholipase A2γ (iPLA2γ), which has been reported to regulate cellular redox homeostasis by inhibiting lipid peroxide accumulation, in human bladder cancer tissues. Thus, we investigated the effect of iPLA2γ knockdown on CDDP-induced bladder cancer cell death. As a result, we found that iPLA2γ knockdown significantly enhanced CDDP-induced apoptosis, intracellular and mitochondrial ROS production, cytochrome c release and caspase activation in bladder cancer cells. Moreover, mitochondrial membrane potential was decreased and peroxidation of mitochondrial phospholipids was increased by iPLA2γ knockdown. It was also shown that co-treatment of bromoenol lactone, an iPLA2 inhibitor, increased CDDP-induced apoptosis. These results indicated that iPLA2γ plays an important role in protecting bladder cancer cells from CDDP-induced apoptosis, and that iPLA2γ inhibitors might represent a novel strategy in CDDP-based multi-drug therapy.
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Affiliation(s)
- Satoko Nakayama
- Department of Urology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8602, Japan
| | - Emiko Yoda
- Division of Health Chemistry, Department of Healthcare and Regulatory Sciences, School of Pharmacy, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, 142-8555, Japan
| | - Saki Yamashita
- Division of Health Chemistry, Department of Healthcare and Regulatory Sciences, School of Pharmacy, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, 142-8555, Japan
| | - Yuka Takamatsu
- Division of Health Chemistry, Department of Healthcare and Regulatory Sciences, School of Pharmacy, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, 142-8555, Japan
| | - Yasutomo Suzuki
- Department of Urology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8602, Japan
| | - Yukihiro Kondo
- Department of Urology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8602, Japan
| | - Shuntaro Hara
- Division of Health Chemistry, Department of Healthcare and Regulatory Sciences, School of Pharmacy, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, 142-8555, Japan.
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2
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Wang Y, Song H, Miao Q, Wang Y, Qi J, Xu X, Sun J. PLA2G6 Silencing Suppresses Melanoma Progression and Affects Ferroptosis Revealed by Quantitative Proteomics. Front Oncol 2022; 12:819235. [PMID: 35340268 PMCID: PMC8948425 DOI: 10.3389/fonc.2022.819235] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Accepted: 02/04/2022] [Indexed: 12/28/2022] Open
Abstract
Although phospholipase A2 group VI (PLA2G6) is involved in oncogenesis in several human tumors, its expression and role in cutaneous malignant melanoma (CMM) pathogenesis remains unclear. Here, by using the Oncomine and CCLE online database, immunohistochemistry, RT-qPCR, and western blotting analysis, we revealed that PLA2G6 was markedly up-regulated in CMM tissues compared to nevus tissues, as well as remarkably increased in vitro in SK-MEL-28 and M14 melanoma cell lines compared to human melanocytes. In vivo, PLA2G6 was also elevated in nine melanoma tissues compared to adjacent tissues. To investigate the malignant behaviors of PLA2G6 in CMM, SK-MEL-28 and M14 cell lines with PLA2G6 stable knockdown by RNAi strategy were constructed. Through CCK8 and colony formation assays in vitro and xenograft tumor experiment in vivo, we found that knockdown of PLA2G6 dramatically inhibited cell proliferation. The results of scratch-wound and transwell assays suggested that the migration and invasion of melanoma cells were prominently suppressed after silencing PLA2G6. In addition, flow cytometry showed that the knockdown of PLA2G6 promoted the apoptosis rate of melanoma cells. To further explore the potential molecular mechanism, we used liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) proteomic and bioinformatics analysis. The GO and KEGG analysis suggested that the underlying mechanism of PLA2G6 in CMM might be associated with the ferroptosis pathway, and ferroptosis-related proteins were validated to be differentially expressed in PLA2G6 knockdown SK-MEL-28 and M14 cells. Together, these results suggested that PLA2G6 knockdown significantly inhibited cell proliferation, metastasis, and promoted apoptosis in melanoma. Our findings on the biological function of PLA2G6 and the underlying association between PLA2G6 and ferroptosis in melanoma may contribute to developing a potential therapeutic strategy for melanoma.
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Affiliation(s)
- Yifei Wang
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China
| | - Hao Song
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China
| | - Qiuju Miao
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China
| | - Yan Wang
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China
| | - Jinliang Qi
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Xiulian Xu
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China
| | - Jianfang Sun
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China
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3
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Cheng KJ, Liang WZ. Influence of a bearing-wastewater phenolic compound (3,4-dimethylphenol, 3,4-DMP) treatment on Ca 2+ homeostasis and its related cytotoxicity in human proximal renal tubular epithelial cells. Hum Exp Toxicol 2021; 40:1899-1908. [PMID: 33906515 DOI: 10.1177/09603271211013453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A lot of phenolic compounds are widespread in industrial effluents and they are considerable environmental pollutants. Being a compound commercially available, the effect of a bearing-wastewater phenolic compound 3,4-dimethylphenol (3,4-DMP) on Ca2+ homeostasis and its related physiology has not been explored in cultured human kidney cell models. The aim of this study was to explore the effect of 3,4-DMP on [Ca2+]i and viability in HK-2 human proximal renal tubular epithelial cells. In terms of Ca2+ signaling, 3,4-DMP (5-100 μM) induced [Ca2+]i rises only in HK-2 cells and Ca2+ removal reduced the signal by 40%. In Ca2+-containing medium, 3,4-DMP-induced Ca2+ entry was inhibited by 20% by a modulator of store-operated Ca2+ channels (2-APB), and by a PKC activator (PMA) and inhibitor (GF109203X). Moreover, 3,4-DMP-induced Mn2+ influx suggesting of Ca2+ entry. In Ca2+-free medium, inhibition of PLC with U73122 abolished 3,4-DMP-induced [Ca2+]i rises. Furthermore, treatment with the endoplasmic reticulum Ca2+ pump inhibitor thapsigargin abolished 3,4-DMP-evoked [Ca2+]i rises. Conversely, treatment with 3,4-DMP abolished thapsigargin-evoked [Ca2+]i rises. Regarding to cell viability, 3,4-DMP (60-140 μM) killed cells in a concentration-dependent fashion in HK-2 cells. Chelation of cytosolic Ca2+ with BAPTA-AM partially reversed cytotoxicity of 3,4-DMP. Collectively, our data suggest that in HK-2 cells, 3,4-DMP-induced [Ca2+]i rises by evoking Ca2+ entry via PKC-sensitive store-operated Ca2+ entry and PLC-dependent Ca2+ release from the endoplasmic reticulum. 3,4-DMP also caused cytotoxicity that was linked to preceding [Ca2+]i rises. Our findings provide new insight into the cytotoxic effects of 3,4-DMP and the possible mechanisms underlying these effects.
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Affiliation(s)
- K-J Cheng
- Department of Nephrology, 210825Kaohsiung Municipal United Hospital, Kaohsiung.,Department of Biological Sciences, National Sun Yat-Sen University, Kaohsiung
| | - W-Z Liang
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.,Department of Pharmacy and Master Program, College of Pharmacy and Health Care, 63299Tajen University, Pingtung County, Taiwan
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4
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The Impact of the Ca 2+-Independent Phospholipase A 2β (iPLA 2β) on Immune Cells. Biomolecules 2021; 11:biom11040577. [PMID: 33920898 PMCID: PMC8071342 DOI: 10.3390/biom11040577] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 04/06/2021] [Accepted: 04/12/2021] [Indexed: 12/31/2022] Open
Abstract
The Ca2+-independent phospholipase A2β (iPLA2β) is a member of the PLA2 family that has been proposed to have roles in multiple biological processes including membrane remodeling, cell proliferation, bone formation, male fertility, cell death, and signaling. Such involvement has led to the identification of iPLA2β activation in several diseases such as cancer, cardiovascular abnormalities, glaucoma, periodontitis, neurological disorders, diabetes, and other metabolic disorders. More recently, there has been heightened interest in the role that iPLA2β plays in promoting inflammation. Recognizing the potential contribution of iPLA2β in the development of autoimmune diseases, we review this issue in the context of an iPLA2β link with macrophages and T-cells.
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5
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Nelson AJ, Stephenson DJ, Cardona CL, Lei X, Almutairi A, White TD, Tusing YG, Park MA, Barbour SE, Chalfant CE, Ramanadham S. Macrophage polarization is linked to Ca 2+-independent phospholipase A 2β-derived lipids and cross-cell signaling in mice. J Lipid Res 2019; 61:143-158. [PMID: 31818877 DOI: 10.1194/jlr.ra119000281] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 11/27/2019] [Indexed: 12/27/2022] Open
Abstract
Phospholipases A2 (PLA2s) catalyze hydrolysis of the sn-2 substituent from glycerophospholipids to yield a free fatty acid (i.e., arachidonic acid), which can be metabolized to pro- or anti-inflammatory eicosanoids. Macrophages modulate inflammatory responses and are affected by Ca2+-independent phospholipase A2 (PLA2)β (iPLA2β). Here, we assessed the link between iPLA2β-derived lipids (iDLs) and macrophage polarization. Macrophages from WT and KO (iPLA2β-/-) mice were classically M1 pro-inflammatory phenotype activated or alternatively M2 anti-inflammatory phenotype activated, and eicosanoid production was determined by ultra-performance LC ESI-MS/MS. As a genotypic control, we performed similar analyses on macrophages from RIP.iPLA2β.Tg mice with selective iPLA2β overexpression in β-cells. Compared with WT, generation of select pro-inflammatory prostaglandins (PGs) was lower in iPLA2β-/- , and that of a specialized pro-resolving lipid mediator (SPM), resolvin D2, was higher; both changes are consistent with the M2 phenotype. Conversely, macrophages from RIP.iPLA2β.Tg mice exhibited an opposite landscape, one associated with the M1 phenotype: namely, increased production of pro-inflammatory eicosanoids (6-keto PGF1α, PGE2, leukotriene B4) and decreased ability to generate resolvin D2. These changes were not linked with secretory PLA2 or cytosolic PLA2α or with leakage of the transgene. Thus, we report previously unidentified links between select iPLA2β-derived eicosanoids, an SPM, and macrophage polarization. Importantly, our findings reveal for the first time that β-cell iPLA2β-derived signaling can predispose macrophage responses. These findings suggest that iDLs play critical roles in macrophage polarization, and we posit that they could be targeted therapeutically to counter inflammation-based disorders.
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Affiliation(s)
- Alexander J Nelson
- Department of Cell, Developmental, and Integrative Biology University of Alabama at Birmingham, Birmingham, AL 35294.,Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Daniel J Stephenson
- Department of Cell Biology, Microbiology, and Molecular Biology (CMMB), University of South Florida, Tampa, FL 33620
| | - Christopher L Cardona
- Department of Cell Biology, Microbiology, and Molecular Biology (CMMB), University of South Florida, Tampa, FL 33620
| | - Xiaoyong Lei
- Department of Cell, Developmental, and Integrative Biology University of Alabama at Birmingham, Birmingham, AL 35294.,Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Abdulaziz Almutairi
- Department of Cell, Developmental, and Integrative Biology University of Alabama at Birmingham, Birmingham, AL 35294.,Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Tayleur D White
- Department of Cell, Developmental, and Integrative Biology University of Alabama at Birmingham, Birmingham, AL 35294.,Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Ying G Tusing
- Department of Cell, Developmental, and Integrative Biology University of Alabama at Birmingham, Birmingham, AL 35294.,Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Margaret A Park
- Department of Cell Biology, Microbiology, and Molecular Biology (CMMB), University of South Florida, Tampa, FL 33620
| | - Suzanne E Barbour
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602
| | - Charles E Chalfant
- Department of Cell Biology, Microbiology, and Molecular Biology (CMMB), University of South Florida, Tampa, FL 33620.,Research Service, James A. Haley Veterans Hospital, Tampa, FL 33612
| | - Sasanka Ramanadham
- Department of Cell, Developmental, and Integrative Biology University of Alabama at Birmingham, Birmingham, AL 35294 .,Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
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Parra JPRLL, Crulhas BP, Basso CR, Delella FK, Castro GR, Pedrosa VA. Using an Electrochemical Aptasensor to Early Detect Prostate Specific and Free Prostate Specific Antigens Released by Cancer Cells. ELECTROANAL 2018. [DOI: 10.1002/elan.201800558] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
| | - Bruno P. Crulhas
- Chemistry and Biochemistry Department, Institute of BioscienceUNESP Botucatu, SP Brazil
| | - Caroline R. Basso
- Chemistry and Biochemistry Department, Institute of BioscienceUNESP Botucatu, SP Brazil
| | - Flávia K. Delella
- Chemistry and Biochemistry Department, Institute of BioscienceUNESP Botucatu, SP Brazil
| | - Gustavo R. Castro
- Chemistry and Biochemistry Department, Institute of BioscienceUNESP Botucatu, SP Brazil
| | - Valber A. Pedrosa
- Chemistry and Biochemistry Department, Institute of BioscienceUNESP Botucatu, SP Brazil
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7
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Positive associations between galectin-3 and PSA levels in prostate cancer patients: a prospective clinical study-I. Oncotarget 2018; 7:82266-82272. [PMID: 27741512 PMCID: PMC5347690 DOI: 10.18632/oncotarget.12619] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 09/20/2016] [Indexed: 01/28/2023] Open
Abstract
Galectin-3 (Gal-3), an oncogenic pro-inflammatory protein, has been suggested as a possible complementary diagnostic candidate to prostate specific antigen (PSA) blood test for prostate cancer patients. The presence of the proteins in the circulation (biomarkers) may elicit an intrinsic humoral immune reaction by generating autoantibodies, which consequently could alter the detection levels. Here, we report the associations of the two prostate cancer biomarkers, Gal-3 and PSA in patients at different clinical states of prostate cancer while taking into account the autoantibody levels. A blind, prospective, single institution, pilot study was conducted. A total of 95 men were classified into 5 groups: healthy controls (Group1), newly diagnosed patients (Group2), no recurrence after local therapy (Group3), rising PSA after local therapy (Group4), and metastatic patients (Group5). Gal-3 and PSA level were divided by their respective autoantibodies, which yielded relative PSA and relative Gal-3 levels. After the adjustments, Spearman's rank correlations and linear regression modeling revealed the positive associations between relative Gal-3 and relative PSA levels among all 95 men combined (rho = 0.446, P < 0.0001; fitted slope 0.448, P < 0.0001), in Group2 (rho = 0.616, P = 0.0050; fitted slope 0.438, P =0.0011), and Group3 (rho = 0.484, P = 0.0360; fitted slope 0.470, P = 0.0187). The data show positive associations of relative Gal-3 and relative PSA levels in prostate cancer patients, notably at early clinical time course. Allowing for the influence of autoantibodies, Gal-3 level might be considered as a potential biomarker since it is positively associated with PSA level.
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8
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The effect of magnolol on Ca 2+ homeostasis and its related physiology in human oral cancer cells. Arch Oral Biol 2018; 89:49-54. [PMID: 29471192 DOI: 10.1016/j.archoralbio.2018.02.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 02/08/2018] [Accepted: 02/11/2018] [Indexed: 11/21/2022]
Abstract
OBJECTIVE Magnolol, a polyphenol compound from herbal medicines, was shown to alter physiology in various cell models. However, the effect of magnolol on Ca2+ homeostasis and its related physiology in oral cancer cells is unclear. This study examined whether magnolol altered Ca2+ signaling and cell viability in OC2 human oral cancer cells. METHODS Cytosolic Ca2+ concentrations ([Ca2+]i) in suspended cells were measured by using the fluorescent Ca2+-sensitive dye fura-2. Cell viability was examined by 4-[3-[4-lodophenyl]-2-4(4-nitrophenyl)-2H-5-tetrazolio-1,3-benzene disulfonate] water soluble tetrazolium-1 (WST-1) assay. RESULTS Magnolol at concentrations of 20-100 μM induced [Ca2+]i rises. Ca2+ removal reduced the signal by approximately 50%. Magnolol (100 μM) induced Mn2+ influx suggesting of Ca2+ entry. Magnolol-induced Ca2+ entry was partially suppressed by protein kinase C (PKC) regulators, and inhibitors of store-operated Ca2+ channels. In Ca2+-free medium, treatment with the endoplasmic reticulum Ca2+ pump inhibitor 2,5-di-tert-butylhydroquinone (BHQ) abolished magnolol-evoked [Ca2+]i rises. Conversely, treatment with magnolol abolished BHQ-evoked [Ca2+]i rises. Inhibition of phospholipase C (PLC) with U73122 partially inhibited magnolol-induced [Ca2+]i rises. Magnolol at 20-100 μM decreased cell viability, which was not reversed by pretreatment with the Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester (BAPTA/AM). CONCLUSIONS Together, in OC2 cells, magnolol induced [Ca2+]i rises by evoking partially PLC-dependent Ca2+ release from the endoplasmic reticulum and Ca2+ entry via PKC-sensitive store-operated Ca2+ entry. Magnolol also caused Ca2+-independent cell death. Therefore, magnolol-induced cytotoxicity may not be involved in activation mechanisms associated with intracellular Ca2+ mobilization in oral cancer cells.
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9
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Crulhas BP, Karpik AE, Delella FK, Castro GR, Pedrosa VA. Electrochemical aptamer-based biosensor developed to monitor PSA and VEGF released by prostate cancer cells. Anal Bioanal Chem 2017; 409:6771-6780. [PMID: 29032455 DOI: 10.1007/s00216-017-0630-1] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 08/30/2017] [Accepted: 09/07/2017] [Indexed: 11/21/2022]
Abstract
Early prostate cancer (PCa) diagnostic is crucial to enhance patient survival rates; besides, non-invasive platforms have been developed worldwide in order to precisely detect PCa biomarkers. Therefore, the aim of the present study is to develop a new aptamer-based biosensor through the self-assembling of thiolated aptamers for PSA and VEGF on the top of gold electrodes. This biosensor was tested in three prostate cell lines (RWPE-1, LNCaP and PC3). The results evidenced a stable and sensitive sensor presenting wide linear detection ranges (0.08-100 ng/mL for PSA and 0.15 ng-100 ng/mL for VEGF). Therefore, the aptasensor was able to detect the patterns of PSA and VEGF released in vitro by PCa cells, which gave new insights about the prostate cancer protein dynamics. Thus, it could be used as a non-invasive PCa clinical diagnosis instrument in the near future. Graphical Abstract Overview of the experimental design applied to the aptamer-based electrochemical sensor self-assembled on the thiolated hairpin structure. A filter membrane was added on top of working electrode to provide the cell-attachment surface after aptamer incubation, without compromising the aptamer layer. The pore membrane allowed target proteins to pass to the aptamer surface; the MCH backfilling avoided unspecific protein binding to the gold electrode surface.
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Affiliation(s)
- Bruno P Crulhas
- Department of Chemistry and Biochemistry, Institute of Bioscience, UNESP-Botucatu, Distrito de Rubiao Jr, 18618-000 Botucatu, São Paulo, 18618-000, Brazil
| | - Agnieszka E Karpik
- Department of Chemistry and Biochemistry, Institute of Bioscience, UNESP-Botucatu, Distrito de Rubiao Jr, 18618-000 Botucatu, São Paulo, 18618-000, Brazil
| | - Flávia K Delella
- Department of Chemistry and Biochemistry, Institute of Bioscience, UNESP-Botucatu, Distrito de Rubiao Jr, 18618-000 Botucatu, São Paulo, 18618-000, Brazil
| | - Gustavo R Castro
- Department of Chemistry and Biochemistry, Institute of Bioscience, UNESP-Botucatu, Distrito de Rubiao Jr, 18618-000 Botucatu, São Paulo, 18618-000, Brazil
| | - Valber A Pedrosa
- Department of Chemistry and Biochemistry, Institute of Bioscience, UNESP-Botucatu, Distrito de Rubiao Jr, 18618-000 Botucatu, São Paulo, 18618-000, Brazil.
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Fang YC, Chou CT, Liang WZ, Kuo CC, Hsu SS, Wang JL, Jan CR. Effect of tetramethylpyrazine (TMP) on Ca 2+ signal transduction and cell viability in a model of renal tubular cells. J Biochem Mol Toxicol 2017; 31. [PMID: 28658523 DOI: 10.1002/jbt.21952] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 05/29/2017] [Accepted: 06/14/2017] [Indexed: 11/09/2022]
Abstract
Tetramethylpyrazine (TMP) is a compound purified from herb. Its effect on Ca2+ concentrations ([Ca2+ ]i ) in renal cells is unclear. This study examined whether TMP altered Ca2+ signaling in Madin-Darby canine kidney (MDCK) cells. TMP at 100-800 μM induced [Ca2+ ]i rises, which were reduced by Ca2+ removal. TMP induced Mn2+ influx implicating Ca2+ entry. TMP-induced Ca2+ entry was inhibited by 30% by modulators of protein kinase C (PKC) and store-operated Ca2+ channels. Treatment with the endoplasmic reticulum Ca2+ pump inhibitor 2,5-di-tert-butylhydroquinone (BHQ) inhibited 93% of TMP-evoked [Ca2+ ]i rises. Treatment with TMP abolished BHQ-evoked [Ca2+ ]i rises. Inhibition of phospholipase C (PLC) abolished TMP-induced responses. TMP at 200-1000 μM decreased viability, which was not reversed by pretreatment with the Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester. Together, in MDCK cells, TMP induced [Ca2+ ]i rises by evoking PLC-dependent Ca2+ release from endoplasmic reticulum and Ca2+ entry via PKC-sensitive store-operated Ca2+ entry. TMP also caused Ca2+ -independent cell death.
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Affiliation(s)
- Yi-Chien Fang
- Department of Laboratory Medicine, Zuoying Branch of Kaohsiung Armed Forces General Hospital, Kaohsiung, 81345, Taiwan
| | - Chiang-Ting Chou
- Department of Nursing, Division of Basic Medical Sciences, Chang Gung University of Science and Technology, Chia-Yi, 61363, Taiwan.,Chronic Diseases and Health Promotion Research Center, Chang Gung University of Science and Technology, Chia-Yi, 61363, Taiwan
| | - Wei-Zhe Liang
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, 81362, Taiwan
| | - Chun-Chi Kuo
- Department of Nursing, Tzu Hui Institute of Technology, Pingtung, 92641, Taiwan
| | - Shu-Shong Hsu
- Department of Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, 81362, Taiwan
| | - Jue-Long Wang
- Department of Rehabilitation, Kaohsiung Veterans General Hospital Tainan Branch, Tainan, 71051, Taiwan
| | - Chung-Ren Jan
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, 81362, Taiwan
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11
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Cheng HH, Chou CT, Liang WZ, Kuo CC, Shieh P, Wang JL, Jan CR. Effects of puerarin on intracellular Ca 2+ and cell viability of MDCK renal tubular cells. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2017; 52:83-89. [PMID: 28384516 DOI: 10.1016/j.etap.2017.03.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 03/20/2017] [Accepted: 03/21/2017] [Indexed: 06/07/2023]
Abstract
Puerarin is a natural compound and has been used as herb medication in a number of countries, especially in Asia. The effect of puerarin on Ca2+ signaling is unknown in renal cells. This study examined whether puerarin affected Ca2+ physiology in MDCK renal tubular cells. Cytosolic free Ca2+ levels ([Ca2+]i) were measured using the fluorescent dye fura-2. Cell viability was examined by using WST-1 assay. Puerarin induced [Ca2+]i rises and the response was reduced by removing extracellular Ca2+. Puerarin-induced Ca2+ entry was not altered by protein kinase C (PKC) activity, but was inhibited by nifedipine. In Ca2+-free medium, treatment with the endoplasmic reticulum Ca2+ pump inhibitor 2,5-di-tert-butylhydroquinone (BHQ) or thapsigargin partly inhibited puerarin-evoked [Ca2+]i rises. Inhibition of phospholipase C (PLC) with U73122 did not change puerarin-induced [Ca2+]i rises. Puerarin at 25-50μM caused cytotoxicity, which was not reversed by pretreatment with the Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester (BAPTA/AM). Collectively, in MDCK cells, puerarin induced [Ca2+]i rises by evoking PLC-independent Ca2+ release from the endoplasmic reticulum and other unknown stores, and Ca2+ entry via nifedipine-sensitive, PKC-insensitive Ca2+ entry pathways. Puerarin also caused Ca2+-independent cell death.
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Affiliation(s)
- He-Hsiung Cheng
- Department of Medicine, Chang Bing Show Chwan Memorial Hospital, Changhua County 50544, Taiwan
| | - Chiang-Ting Chou
- Department of Nursing, Division of Basic Medical Sciences, Chang Gung University of Science and Technology, Chia-Yi 61363, Taiwan; Chronic Diseases and Health Promotion Research Center, Chang Gung University of Science and Technology, Chia-Yi 61363, Taiwan
| | - Wei-Zhe Liang
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung 81362, Taiwan
| | - Chun-Chi Kuo
- Department of Nursing, Tzu Hui Institute of Technology, Pingtung 92641, Taiwan
| | - Pochuan Shieh
- Department of Pharmacy, Tajen University, Pingtung 90741, Taiwan.
| | - Jue-Long Wang
- Department of Rehabilitation, Kaohsiung Veterans General Hospital Tainan Branch, Tainan 71051, Taiwan.
| | - Chung-Ren Jan
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung 81362, Taiwan.
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Su CK, Chou CT, Lin KL, Liang WZ, Cheng JS, Chang HT, Chen IS, Lu T, Kuo CC, Yu CC, Shieh P, Kuo DH, Chen FA, Jan CR. Effect of protriptyline on [Ca2+]i and viability in MG63 human osteosarcoma cells. Toxicol Mech Methods 2016; 26:580-587. [DOI: 10.1080/15376516.2016.1216208] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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13
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The effect of the phenol compound ellagic acid on Ca2+ homeostasis and cytotoxicity in liver cells. Eur J Pharmacol 2016; 780:243-51. [DOI: 10.1016/j.ejphar.2016.03.057] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 03/24/2016] [Accepted: 03/29/2016] [Indexed: 01/21/2023]
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14
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Bromoenol Lactone Attenuates Nicotine-Induced Breast Cancer Cell Proliferation and Migration. PLoS One 2015; 10:e0143277. [PMID: 26588686 PMCID: PMC4654479 DOI: 10.1371/journal.pone.0143277] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2015] [Accepted: 11/03/2015] [Indexed: 12/18/2022] Open
Abstract
Objectives Calcium independent group VIA phospholipase A2 (iPLA2β) and Matrix Metalloproteinase-9 (MMP-9) are upregulated in many disease states; their involvement with cancer cell migration has been a recent subject for study. Further, the molecular mechanisms mediating nicotine-induced breast cancer cell progression have not been fully investigated. This study aims to investigate whether iPLA2β mediates nicotine-induced breast cancer cell proliferation and migration through both in-vitro and in-vivo techniques. Subsequently, the ability of Bromoenol Lactone (BEL) to attenuate the severity of nicotine-induced breast cancer was examined. Method and Results We found that BEL significantly attenuated both basal and nicotine-induced 4T1 breast cancer cell proliferation, via an MTT proliferation assay. Breast cancer cell migration was examined by both a scratch and transwell assay, in which, BEL was found to significantly decrease both basal and nicotine-induced migration. Additionally, nicotine-induced MMP-9 expression was found to be mediated in an iPLA2β dependent manner. These results suggest that iPLA2β plays a critical role in mediating both basal and nicotine-induced breast cancer cell proliferation and migration in-vitro. In an in-vivo mouse breast cancer model, BEL treatment was found to significantly reduce both basal (p<0.05) and nicotine-induced tumor growth (p<0.01). Immunohistochemical analysis showed BEL decreased nicotine-induced MMP-9, HIF-1alpha, and CD31 tumor tissue expression. Subsequently, BEL was observed to reduce nicotine-induced lung metastasis. Conclusion The present study indicates that nicotine-induced migration is mediated by MMP-9 production in an iPLA2β dependent manner. Our data suggests that BEL is a possible chemotherapeutic agent as it was found to reduce both nicotine-induced breast cancer tumor growth and lung metastasis.
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Chang HT, Chou CT, Yu CC, Tsai JY, Sun TK, Liang WZ, Lin KL, Tseng HW, Kuo CC, Chen FA, Kuo DH, Pan CC, Ho CM, Shieh P, Jan CR. The mechanism of protriptyline-induced Ca2+movement and non-Ca2+-triggered cell death in PC3 human prostate cancer cells. J Recept Signal Transduct Res 2015; 35:429-34. [DOI: 10.3109/10799893.2014.1000464] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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16
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Ramanadham S, Ali T, Ashley JW, Bone RN, Hancock WD, Lei X. Calcium-independent phospholipases A2 and their roles in biological processes and diseases. J Lipid Res 2015; 56:1643-68. [PMID: 26023050 DOI: 10.1194/jlr.r058701] [Citation(s) in RCA: 135] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Indexed: 12/24/2022] Open
Abstract
Among the family of phospholipases A2 (PLA2s) are the Ca(2+)-independent PLA2s (iPLA2s) and they are designated group VI iPLA2s. In relation to secretory and cytosolic PLA2s, the iPLA2s are more recently described and details of their expression and roles in biological functions are rapidly emerging. The iPLA2s or patatin-like phospholipases (PNPLAs) are intracellular enzymes that do not require Ca(2+) for activity, and contain lipase (GXSXG) and nucleotide-binding (GXGXXG) consensus sequences. Though nine PNPLAs have been recognized, PNPLA8 (membrane-associated iPLA2γ) and PNPLA9 (cytosol-associated iPLA2β) are the most widely studied and understood. The iPLA2s manifest a variety of activities in addition to phospholipase, are ubiquitously expressed, and participate in a multitude of biological processes, including fat catabolism, cell differentiation, maintenance of mitochondrial integrity, phospholipid remodeling, cell proliferation, signal transduction, and cell death. As might be expected, increased or decreased expression of iPLA2s can have profound effects on the metabolic state, CNS function, cardiovascular performance, and cell survival; therefore, dysregulation of iPLA2s can be a critical factor in the development of many diseases. This review is aimed at providing a general framework of the current understanding of the iPLA2s and discussion of the potential mechanisms of action of the iPLA2s and related involved lipid mediators.
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Affiliation(s)
- Sasanka Ramanadham
- Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294 Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Tomader Ali
- Undergraduate Research Office, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Jason W Ashley
- Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA 19104
| | - Robert N Bone
- Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294 Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
| | - William D Hancock
- Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294 Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Xiaoyong Lei
- Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294 Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, AL 35294
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Chien JM, Chou CT, Liang WZ, Cheng JS, Chang HT, Tseng HW, Kuo SY, Kuo CC, Chen FA, Shieh P, Ho CM, Lin JR, Kuo DH, Jan CR. Effect of deoxycholic acid on Ca2+ movement, cell viability and apoptosis in human gastric cancer cells. Toxicol Mech Methods 2014; 25:113-9. [PMID: 25406855 DOI: 10.3109/15376516.2014.990597] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Deoxycholic acid (DOA) is one of the secondary bile acids used as a mild detergent for the isolation of membrane associated proteins. This study examined whether the secondary bile acid, DOA, altered Ca(2+) movement, cell viability and apoptosis in SCM1 human gastric cancer cells. The Ca(2+)-sensitive fluorescent dye fura-2 was used to measure [Ca(2+)]i. DOA-evoked [Ca(2+)]i rises concentration dependently. The response was reduced by removing extracellular Ca(2+). DOA-evoked Ca(2+) entry was inhibited by store-operated Ca(2+) channel inhibitors (nifedipine, econazole and SKF96365), the protein kinase C (PKC) activator phorbol 12-myristate 13 acetate (PMA) and the PKC inhibitor GF109203X. In Ca(2+)-free medium, treatment with the endoplasmic reticulum Ca(2+) pump inhibitor thapsigargin (TG) abolished DOA-evoked [Ca(2+)]i rises. Conversely, treatment with DOA abolished TG-evoked [Ca(2+)]i rises. Inhibition of phospholipase C with U73122 abolished DOA-evoked [Ca(2+)]i rises. At 100-500 μM, DOA decreased cell viability, which was not changed by chelating cytosolic Ca(2+) with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester (BAPTA/AM). DOA between 100 and 300 μM also induced apoptosis. Collectively, in SCM1 cells, DOA-induced [Ca(2+)]i rises by evoking phospholipase C-dependent Ca(2+) release from the endoplasmic reticulum and Ca(2+) entry via store-operated Ca(2+) channels. DOA also caused Ca(2+)-independent apoptosis.
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Affiliation(s)
- Jau-Min Chien
- Department of Pediatrics, Ping Tung Christian Hospital , Ping Tung , Taiwan
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18
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Yu CC, Chou CT, Sun TK, Liang WZ, Cheng JS, Chang HT, Wang JL, Tseng HW, Kuo CC, Chen FA, Kuo DH, Shieh P, Jan CR. Effect of melamine on [Ca(2+)]i and viability in PC3 human prostate cancer cells. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2014; 38:800-806. [PMID: 25305741 DOI: 10.1016/j.etap.2014.09.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Accepted: 09/19/2014] [Indexed: 06/04/2023]
Abstract
Melamine is thought to be an endocrine disrupter that affects physiology in cells. This study examined the effect of melamine on cytosolic free Ca(2+) concentrations ([Ca(2+)]i) and viability in PC3 human prostate cancer cells. Melamine evoked [Ca(2+)]i rises concentration-dependently. Melamine-evoked Ca(2+) entry was inhibited by nifedipine, econazole, SKF96365, GF109203X and phorbol 12-myristate 13 acetate. In Ca(2+)-free medium, treatment with the endoplasmic reticulum Ca(2+) pump inhibitor thapsigargin inhibited melamine-evoked [Ca(2+)]i rise. Conversely, treatment with melamine abolished thapsigargin-evoked [Ca(2+)]i rise. Inhibition of phospholipase C with U73122 did not alter melamine-evoked [Ca(2+)]i rise. Melamine at 500-800μM decreased cell viability, which was not reversed by pretreatment with the Ca(2+) chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester (BAPTA/AM). Collectively, our data suggest that in PC3 cells, melamine induced [Ca(2+)]i rises by evoking phospholipase C-independent Ca(2+) release from the endoplasmic reticulum, and Ca(2+) entry via protein kinase C-regulated store-operated Ca(2+) entry. Melamine also caused Ca(2+)-independent cell death.
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Affiliation(s)
- Chia-Cheng Yu
- Department of Surgery, Kaohsiung Veterans General Hospital, Kaohsiung 81362, Taiwan
| | - Chiang-Ting Chou
- Department of Nursing, Division of Basic Medical Sciences, Chang Gung Institute of Technology, Chia-Yi 61363, Taiwan; Chronic Diseases and Health Promotion Research Center, Chang Gung Institute of Technology, Chia-Yi 61363, Taiwan
| | - Te-Kung Sun
- Division of Pediatrics, St. Joseph Hospital, Kaohsiung 80288, Taiwan
| | - Wei-Zhe Liang
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung 81362, Taiwan
| | - Jin-Shiung Cheng
- Department of Medicine, Kaohsiung Veterans General Hospital, Kaohsiung 81362, Taiwan
| | - Hong-Tai Chang
- Department of Surgery, Kaohsiung Veterans General Hospital, Kaohsiung 81362, Taiwan
| | - Jue-Long Wang
- Department of Rehabilitation, Kaohsiung Veterans General Hospital, Kaohsiung 81362, Taiwan
| | - Hui-Wen Tseng
- Department of Dermatology, Kaohsiung Veterans General Hospital, Kaohsiung 81362, Taiwan
| | - Chun-Chi Kuo
- Department of Nursing, Tzu Hui Institute of Technology, Pingtung 92641, Taiwan
| | - Fu-An Chen
- Department of Pharmacy, Tajen University, Pingtung 90741, Taiwan
| | - Daih-Huang Kuo
- Department of Pharmacy, Tajen University, Pingtung 90741, Taiwan
| | - Pochuen Shieh
- Department of Pharmacy, Tajen University, Pingtung 90741, Taiwan
| | - Chung-Ren Jan
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung 81362, Taiwan.
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Liang WZ, Chou CT, Chang HT, Cheng JS, Kuo DH, Ko KC, Chiang NN, Wu RF, Shieh P, Jan CR. The mechanism of honokiol-induced intracellular Ca(2+) rises and apoptosis in human glioblastoma cells. Chem Biol Interact 2014; 221:13-23. [PMID: 25106108 DOI: 10.1016/j.cbi.2014.07.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 07/15/2014] [Accepted: 07/25/2014] [Indexed: 12/21/2022]
Abstract
Honokiol, an active constituent of oriental medicinal herb Magnolia officinalis, caused Ca(2+) mobilization and apoptosis in different cancer cells. In vivo, honokiol crossed the blood-brain or -cerebrospinal fluid barrier, suggesting that it may be an effective drug for the treatment of brain tumors, including glioblastoma. This study examined the effect of honokiol on intracellular Ca(2+) concentration ([Ca(2+)]i) and apoptosis in DBTRG-05MG human glioblastoma cells. Honokiol concentration-dependently induced a [Ca(2+)]i rise. The signal was decreased partially by removal of extracellular Ca(2+). Honokiol-triggered [Ca(2+)]i rise was not suppressed by store-operated Ca(2+) channel blockers (nifedipine, econazole, SK&F96365) and the protein kinase C (PKC) activator phorbol 12-myristate 13 acetate (PMA), but was inhibited by the PKC inhibitor GF109203X. GF109203X-induced inhibition was not altered by removal of extracellular Ca(2+). In Ca(2+)-free medium, pretreatment with the endoplasmic reticulum Ca(2+) pump inhibitor thapsigargin (TG) or 2,5-di-tert-butylhydroquinone (BHQ) abolished honokiol-induced [Ca(2+)]i rise. Conversely, incubation with honokiol abolished TG or BHQ-induced [Ca(2+)]i rise. Inhibition of phospholipase C (PLC) with U73122 abolished honokiol-induced [Ca(2+)]i rise. Honokiol (20-80μM) reduced the cell viability, which was not reversed by prechelating cytosolic Ca(2+) with BAPTA-AM (1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester). Honokiol (20-60μM) enhanced reactive oxygen species (ROS) production, decreased mitochondrial membrane potential, released cytochrome c, and activated caspase-9/caspase-3. Together, honokiol induced a [Ca(2+)]i rise by inducing PLC-dependent Ca(2+) release from the endoplasmic reticulum and Ca(2+) entry via PKC-dependent, non store-operated Ca(2+) channels. Moreover, honokiol activated the mitochondrial pathway of apoptosis in DBTRG-05MG human glioblastoma cells.
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Affiliation(s)
- Wei-Zhe Liang
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung 813, Taiwan, ROC
| | - Chiang-Ting Chou
- Department of Nursing, Division of Basic Medical Sciences, Chang Gung University of Science and Technology, Chia-Yi 613, Taiwan, ROC; Chronic Diseases and Health Promotion Research Center, Chang Gung University of Science and Technology, Chia-Yi 613, Taiwan, ROC
| | - Hong-Tai Chang
- Department of Surgery, Kaohsiung Veterans General Hospital, Kaohsiung 813, Taiwan, ROC
| | - Jin-Shiung Cheng
- Department of Medicine, Kaohsiung Veterans General Hospital, Kaohsiung 813, Taiwan, ROC
| | - Daih-Huang Kuo
- Department of Pharmacy, Tajen University, Pingtung 907, Taiwan, ROC
| | - Kuang-Chung Ko
- Department of Gastroenterology, Kaohsiung Veterans General Hospital-Pingtung Branch 912, Taiwan, ROC
| | - Ni-Na Chiang
- Department of Pharmacy, Kaohsiung Veterans General Hospital-Pingtung Branch 912, Taiwan, ROC
| | - Ru-Fang Wu
- Department of Pharmacy, Kaohsiung Municipal Kai-Syuan Psychiatric Hospital, Kaohsiung 802, Taiwan, ROC
| | - Pochuen Shieh
- Department of Pharmacy, Tajen University, Pingtung 907, Taiwan, ROC
| | - Chung-Ren Jan
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung 813, Taiwan, ROC.
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20
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Dolega ME, Wagh J, Gerbaud S, Kermarrec F, Alcaraz JP, Martin DK, Gidrol X, Picollet-D’hahan N. Facile bench-top fabrication of enclosed circular microchannels provides 3D confined structure for growth of prostate epithelial cells. PLoS One 2014; 9:e99416. [PMID: 24945245 PMCID: PMC4063722 DOI: 10.1371/journal.pone.0099416] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 05/14/2014] [Indexed: 12/15/2022] Open
Abstract
We present a simple bench-top method to fabricate enclosed circular channels for biological experiments. Fabricating the channels takes less than 2 hours by using glass capillaries of various diameters (from 100 µm up to 400 µm) as a mould in PDMS. The inner surface of microchannels prepared in this way was coated with a thin membrane of either Matrigel or a layer-by-layer polyelectrolyte to control cellular adhesion. The microchannels were then used as scaffolds for 3D-confined epithelial cell culture. To show that our device can be used with several epithelial cell types from exocrine glandular tissues, we performed our biological studies on adherent epithelial prostate cells (non-malignant RWPE-1 and invasive PC3) and also on breast (non-malignant MCF10A) cells We observed that in static conditions cells adhere and proliferate to form a confluent layer in channels of 150 µm in diameter and larger, whereas cellular viability decreases with decreasing diameter of the channel. Matrigel and PSS (poly (sodium 4-styrenesulphonate)) promote cell adhesion, whereas the cell proliferation rate was reduced on the PAH (poly (allylamine hydrochloride))-terminated surface. Moreover infusing channels with a continuous flow did not induce any cellular detachment. Our system is designed to simply grow cells in a microchannel structure and could be easily fabricated in any biological laboratory. It offers opportunities to grow epithelial cells that support the formation of a light. This system could be eventually used, for example, to collect cellular secretions, or study cell responses to graduated hypoxia conditions, to chemicals (drugs, siRNA, …) and/or physiological shear stress.
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Affiliation(s)
- Monika E. Dolega
- Univ. Grenoble Alpes, iRTSV-BGE, Grenoble, France
- CEA, iRTSV-BGE, Grenoble, France
- INSERM, BGE, Grenoble, France
| | - Jayesh Wagh
- Univ. Grenoble Alpes, iRTSV-BGE, Grenoble, France
- CEA, iRTSV-BGE, Grenoble, France
- INSERM, BGE, Grenoble, France
| | - Sophie Gerbaud
- Univ. Grenoble Alpes, iRTSV-BGE, Grenoble, France
- CEA, iRTSV-BGE, Grenoble, France
- INSERM, BGE, Grenoble, France
| | - Frederique Kermarrec
- Univ. Grenoble Alpes, iRTSV-BGE, Grenoble, France
- CEA, iRTSV-BGE, Grenoble, France
- INSERM, BGE, Grenoble, France
| | | | - Donald K. Martin
- UJF-Grenoble 1, CNRS, TIMC-IMAG UMR 5525 (SyNaBi), Grenoble, France
| | - Xavier Gidrol
- Univ. Grenoble Alpes, iRTSV-BGE, Grenoble, France
- CEA, iRTSV-BGE, Grenoble, France
- INSERM, BGE, Grenoble, France
| | - Nathalie Picollet-D’hahan
- Univ. Grenoble Alpes, iRTSV-BGE, Grenoble, France
- CEA, iRTSV-BGE, Grenoble, France
- INSERM, BGE, Grenoble, France
- * E-mail:
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21
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Chang HJ, Chou CT, Chang HT, Liang WZ, Hung TY, Li YD, Fang YC, Kuo CC, Kuo DH, Shieh P, Jan CR. Mechanisms of resveratrol-induced changes in cytosolic free calcium ion concentrations and cell viability in OC2 human oral cancer cells. Hum Exp Toxicol 2014; 34:289-99. [PMID: 24925362 DOI: 10.1177/0960327114537536] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Resveratrol is a natural compound that affects cellular calcium (Ca(2+)) homeostasis and viability in different cells. This study examined the effect of resveratrol on cytosolic free Ca(2+) concentrations ([Ca(2+)]i) and viability in OC2 human oral cancer cells. The Ca(2+)-sensitive fluorescent dye fura-2 was used to measure [Ca(2+)]i, and water-soluble tetrazolium-1 was used to measure viability. Resveratrol evoked concentration-dependent increase in [Ca(2+)]i. The response was reduced by removing extracellular Ca(2+). Resveratrol also caused manganese-induced fura-2 fluorescence quench. Resveratrol-evoked Ca(2+) entry was inhibited by nifedipine and the protein kinase C (PKC) inhibitor GF109203X but was not altered by econazole, SKF96365, and the PKC activator phorbol 12-myristate 13 acetate. In Ca(2+)-free medium, treatment with the endoplasmic reticulum Ca(2+) pump inhibitor 2,5-di-tert-butylhydroquinone (BHQ) abolished resveratrol-evoked [Ca(2+)]i rise. Conversely, treatment with resveratrol inhibited BHQ-evoked [Ca(2+)]i rise. Inhibition of phospholipase C (PLC) with U73122 abolished resveratrol-evoked [Ca(2+)]i rise. At 20-100 μM, resveratrol decreased cell viability, which was not affected by chelating cytosolic Ca(2+)with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester. Annexin V-fluorescein isothiocyanate staining data suggest that resveratrol at 20-40 μM induced apoptosis in a concentration-dependent manner. Collectively, in OC2 cells, resveratrol induced [Ca(2+)]i rise by evoking PLC-dependent Ca(2+) release from the endoplasmic reticulum and by causing Ca(2+) entry via nifedipine-sensitive, PKC-regulated mechanisms. Resveratrol also caused Ca(2+)-independent apoptosis.
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Affiliation(s)
- H-J Chang
- Department of Dentistry, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - C-T Chou
- Department of Nursing, Division of Basic Medical Sciences, Chang Gung University of Science and Technology, Chia-Yi, Taiwan Chronic Diseases and Health Promotion Research Center, Chang Gung University of Science and Technology, Chia-Yi, Taiwan
| | - H-T Chang
- Department of Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan College of Management, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - W-Z Liang
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - T-Y Hung
- Department of Laboratory Medicine, Zuoying Armed Forces General Hospital, Kaohsiung, Taiwan
| | - Y-D Li
- Department of Laboratory Medicine, Zuoying Armed Forces General Hospital, Kaohsiung, Taiwan
| | - Y-C Fang
- Department of Laboratory Medicine, Zuoying Armed Forces General Hospital, Kaohsiung, Taiwan
| | - C-C Kuo
- Department of Nursing, Tzu Hui Institute of Technology, Pingtung, Taiwan
| | - D-H Kuo
- Department of Pharmacy, Tajen University, Pingtung, Taiwan
| | - P Shieh
- Department of Pharmacy, Tajen University, Pingtung, Taiwan
| | - C-R Jan
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
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22
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Chang HT, Chou CT, Chen IL, Liang WZ, Kuo DH, Huang JK, Shieh P, Jan CR. Mechanisms of resveratrol-induced changes in [Ca2+]iand cell viability in PC3 human prostate cancer cells. J Recept Signal Transduct Res 2013; 33:298-303. [DOI: 10.3109/10799893.2013.822886] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Callaghan CM, Johnson A, Neumann P, Leggett RE, Schuler C, Levin RM. The effect of partial outlet obstruction on calpain and phospholipase-2 activities: analyzed by severity and duration. Mol Cell Biochem 2013; 381:217-20. [PMID: 23737136 DOI: 10.1007/s11010-013-1705-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2013] [Accepted: 05/24/2013] [Indexed: 12/23/2022]
Abstract
In an attempt to better understand the two pathways that lead to bladder decompensation following partial obstruction in rabbits one of which is caused by calcium-activated enzymes and the other by oxidative stress, calpain and phospholipase A2 (PLA2) biochemical assays were conducted to see how bladder decompensation is mediated by these two calcium-activated enzymes. Partial outlet obstructions of varying durations (4, 8, and 12 weeks plus controls) were performed on 32 New Zealand white rabbits. The rabbits were also grouped by severity: control, mild, intermediate, and severe. The activities of Calpain and PLA2 on the muscle tissue of the bladders were analyzed. A stronger correlation was seen between activities and severities as opposed to between activities and durations for both PLA2 and calpain. The activity for PLA2 increased dramatically from control to mild and then stayed constant for both intermediate and severe obstructions. Calpain activity increased steadily from control to mild to intermediate to severe. Based on the increase in levels of the calcium-dependent enzymes, it was clearly shown that calcium levels increased in all stages of bladder decompensation most notably with the mild obstructions. Based on previous studies in which nitrotyrosine and dinitrophenol levels did not increase in mildly obstructed rabbits, the calcium overload pathway may predominate in mild decompensation because cells in mildly obstructed bladders are better able to cope with oxidative stress than increased calcium levels.
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Affiliation(s)
- Connor M Callaghan
- Pharmacy Practice, Albany College of Pharmacy and Health Sciences, Albany, NY 12208, USA
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24
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Caron D, Maaroufi H, Michaud S, Tanguay RM, Faure RL. Annexin A1 is regulated by domains cross-talk through post-translational phosphorylation and SUMOYlation. Cell Signal 2013; 25:1962-9. [PMID: 23727357 DOI: 10.1016/j.cellsig.2013.05.028] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Revised: 05/15/2013] [Accepted: 05/15/2013] [Indexed: 12/24/2022]
Abstract
Mouse prostate membrane-associated proteins of the annexin family showed changes in SUMOylation during androgen treatment. Among these the calcium-binding annexin A1 protein (ANXA1) was chosen for further characterization given its role in protein secretion and cancer. SUMOylation of ANXA1 was confirmed by overexpressing SUMO-1 in LNCaP cells. Site-directed mutagenesis indicated that K257 located in a SUMOylation consensus motif in the C-terminal calcium-binding DA3 repeat domain is SUMOylated. Mutation of the N-terminal Y21 decreased markedly the SUMOylation signal while EGF stimulation increased ANXA1 SUMOylation. A structural analysis of ANXA1 revealed that K257 is located in a hot spot where Ca(2+) and SUMO-1 bind and where a nuclear export signal and a polyubiquitination site are also present. Also, Y21 is buried inside an α-helix structure in the Ca(2+)-free conformation implying that Ca(2+) binding, and the subsequent expelling of the N-terminal α-helix in a disordered conformation, is permissive for its phosphorylation. These results show for the first time that SUMOylation can be regulated by an external signal (EGF) and indicate the presence of a cross-talk between the N-terminal and C-terminal domains of ANXA1 through post-translational modifications.
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Affiliation(s)
- Danielle Caron
- Department of Pediatrics, Laboratory of Cellular Biology, Centre de recherche du CHUQ Centre-Mère-Enfant Soleil, Canada
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Chang HT, Chen IL, Chou CT, Liang WZ, Kuo DH, Shieh P, Jan CR. Effect of caffeic acid on Ca2+ homeostasis and apoptosis in SCM1 human gastric cancer cells. Arch Toxicol 2013; 87:2141-50. [DOI: 10.1007/s00204-013-1075-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 05/06/2013] [Indexed: 10/26/2022]
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Horng CT, Chiang NN, Chen IL, Liang WZ, Chen IS, Kuo DH, Shieh PC, Jan CR. Effect of clotrimazole on cytosolic Ca2+rise and viability in HA59T human hepatoma cells. J Recept Signal Transduct Res 2013; 33:89-95. [DOI: 10.3109/10799893.2013.764321] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Hirsch J, Johnson CL, Nelius T, Kennedy R, Riese WD, Filleur S. PEDF inhibits IL8 production in prostate cancer cells through PEDF receptor/phospholipase A2 and regulation of NFκB and PPARγ. Cytokine 2011; 55:202-10. [PMID: 21570865 DOI: 10.1016/j.cyto.2011.04.010] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2010] [Revised: 03/02/2011] [Accepted: 04/15/2011] [Indexed: 11/19/2022]
Abstract
Interleukin-8 (IL8/CXCL8) has been described as a key effector in prostate cancer progression and resistance to standard chemotherapeutic drugs. In the present study, we investigated the effect of the natural, angio-inhibitory and anti-tumoral Pigment Epithelium-Derived Factor (PEDF) on the expression of IL8 cytokine by prostate cancer cells. Using a cytokine antibody array and ELISA, in addition to IL8 quantitative RT PCR, we showed that PEDF inhibits the production of IL8 in human hormone-refractory prostate cancer cells, and delays the growth of these cells in vitro. IL8 reduction was mimicked in cancer cells treated with PPARγ agonist and NFκB-specific inhibitors. Accordingly, PPARγ expression increased in response to PEDF, whereas RelA/p65 expression and nuclear localization, and NFκB transcriptional activity decreased. NFκB deactivation was reversed by the PPARγ antagonist GW9662 and PPARγ (Leu(468)/Glu(471)) dominant negative suggesting a PPARγ-dependent process. We also investigated PEDF Receptor/PLA2 as key player in this pathway by small interference RNA. PEDFR knock down in prostate cancer cells reversed PEDF-induced PPARγ up-regulation, and NFκB and IL8 inhibition compared to non-targeting control siRNA. We conclude that by binding to PEDFR, PEDF up-regulates PPARγ, leading subsequently to suppressed NFκB-mediated transcriptional activation, reduced production of IL8 and limited proliferation of prostate cancer cells. These results reinforce PEDF's therapeutic potential and imply that blocking IL8 could represent a novel alternative for prostate cancer treatment.
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Affiliation(s)
- Jennifer Hirsch
- Department of Urology, Texas Tech University-Health Sciences Center, Lubbock, TX 79430, USA.
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Li H, Zhang H, Wei G, Cai Q, Yan L, Xu Y. Tumor cell group via phospholipase A₂ is involved in prostate cancer development. Prostate 2011; 71:373-84. [PMID: 20812222 DOI: 10.1002/pros.21251] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2010] [Accepted: 07/22/2010] [Indexed: 11/11/2022]
Abstract
BACKGROUND Prostate cancer (PCa) is one of the most common malignancies among men in the United States. Further understanding of the molecular mechanisms underlying PCa tumorigenic development is critical for advancing treatment strategies for PCa. The role of Group VIA phospholipase A₂β (iPLA₂β) in cancers has recently emerged. However, the biological functions of iPLA₂β in PCa development have been minimally investigated and only in vitro studies have been reported. METHODS We tested the role of iPLA₂β in host cells using an iPLA₂β deficient mouse model and the role of iPLA₂β in tumor cells by comparing the proliferation, migration, and invasion in vitro and tumorigenesis in vivo. CONCLUSIONS iPLA₂β deficiency did not affect tumor development in C57BL/6 mice injected with syngeneic PCa cell line TRAMP-C1P3 in any of three models (subcutaneous, orthotopic, or intratibia injection) tested, suggesting that host cell iPLA₂β is not required for PCa tumorigenesis and metastasis. In contrast, when iPLA₂β was down-regulated in TRAMP-C1P3 cells, cell proliferation was reduced in vitro and tumor growth was suppressed in vivo compared to control cells. In particular, iPLA₂β was required for lysophosphatidic acid (LPA)-induced migration and invasion in TRAMP-C1P3 cells. We compared human and mouse PCa cells and showed that they shared high similarities in LPA-stimulated effects and signaling pathways. LPA stimulated cell migration and/or invasion via a PI3K-dependent pathway. Together, our results suggest that the tumor cell iPLA₂β-LPA axis may represent a novel target for PCa.
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Affiliation(s)
- Hui Li
- Department of Obstetrics and Gynecology, Indiana University, Indianapolis, Indiana 46202, USA
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McHowat J, Gullickson G, Hoover RG, Sharma J, Turk J, Kornbluth J. Platelet-activating factor and metastasis: calcium-independent phospholipase A2β deficiency protects against breast cancer metastasis to the lung. Am J Physiol Cell Physiol 2011; 300:C825-32. [PMID: 21228317 DOI: 10.1152/ajpcell.00502.2010] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We determined the contribution of calcium-independent phospholipase A(2)β (iPLA(2)β) to lung metastasis development following breast cancer injection into wild-type (WT) and iPLA(2)β-knockout (iPLA(2)β-KO) mice. WT and iPLA(2)β-KO mice were injected in the mammary pad with 200,000 E0771 breast cancer cells. There was no difference in primary tumor size between WT and iPLA(2)β-KO mice at 27 days postinjection. However, we observed an 11-fold greater number of breast cancer cells in the lungs of WT mice compared with iPLA(2)β-KO animals (P < 0.05). Isolated WT lung endothelial cells demonstrated a significant increase in platelet-activating factor (PAF) production when stimulated with thrombin [1 IU/ml, 10 min, 4,330 ± 555 vs. 15,227 ± 1,043 disintegrations per minute (dpm), P < 0.01] or TNF-α (10 ng/ml, 2 h, 16,532 ± 538 dpm, P < 0.01). Adherence of E0771 cells to WT endothelial cells was increased by thrombin (4.8 ± 0.3% vs. 70.9 ± 6.3, P < 0.01) or TNF-α (60.5 ± 4.3, P < 0.01). These responses were blocked by pretreatment with the iPLA(2)β-selective inhibitor (S)-bromoenol lactone and absent in lung endothelial cells from iPLA(2)β-KO mice. These data indicate that endothelial cell iPLA(2)β is responsible for PAF production and adherence of E0771 cells and may play a role in cancer cell migration to distal locations.
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Affiliation(s)
- Jane McHowat
- Department of Pathology, Saint Louis University School of Medicine, Missouri 63104, USA.
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Misra UK, Payne S, Pizzo SV. Ligation of prostate cancer cell surface GRP78 activates a proproliferative and antiapoptotic feedback loop: a role for secreted prostate-specific antigen. J Biol Chem 2010; 286:1248-59. [PMID: 21056970 DOI: 10.1074/jbc.m110.129767] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
GRP78, a well characterized chaperone in the endoplasmic reticulum, is critical to the unfolded protein response. More recently, it has been identified on the cell surface, where it has many roles. On cancer cells, it functions as a signaling receptor coupled to proproliferative/antiapoptotic and promigratory mechanisms. In the current study, we demonstrate that ligation of prostate cancer cell surface GRP78 by its natural ligand, activated α(2)-macroglobulin (α(2)M*), results in a 2-3-fold up-regulation in the synthesis of prostate-specific antigen (PSA). The PSA is secreted into the medium as an active proteinase, where it binds to native α(2)M. The resultant α(2)M·PSA complexes bind to GRP78, causing a 1.5-2-fold increase in the activation of MEK1/2, ERK1/2, S6K, and Akt, which is coupled with a 2-3-fold increase in DNA and protein synthesis. PSA is a marker for the progression of prostate cancer, but its mechanistic role in the disease is unclear. The present studies suggest that PSA may be involved in a signal transduction-dependent feedback loop, whereby it promotes a more aggressive behavior by human prostate cancer cells.
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Affiliation(s)
- Uma K Misra
- Department of Pathology, Duke University Medical Center, Durham, North Carolina 27710, USA
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Itagaki K, Menconi M, Antoniu B, Zhang Q, Gonnella P, Soybel D, Hauser C, Hasselgren PO. Dexamethasone stimulates store-operated calcium entry and protein degradation in cultured L6 myotubes through a phospholipase A(2)-dependent mechanism. Am J Physiol Cell Physiol 2010; 298:C1127-39. [PMID: 20107037 DOI: 10.1152/ajpcell.00309.2009] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Muscle wasting in various catabolic conditions is at least in part regulated by glucocorticoids. Increased calcium levels have been reported in atrophying muscle. Mechanisms regulating calcium homeostasis in muscle wasting, in particular the role of glucocorticoids, are poorly understood. Here we tested the hypothesis that glucocorticoids increase intracellular calcium concentrations in skeletal muscle and stimulate store-operated calcium entry (SOCE) and that these effects of glucocorticoids may at least in part be responsible for glucocorticoid-induced protein degradation. Treatment of cultured myotubes with dexamethasone, a frequently used in vitro model of muscle wasting, resulted in increased intracellular calcium concentrations determined by fura-2 AM fluorescence measurements. When SOCE was measured by using calcium "add-back" to muscle cells after depletion of intracellular calcium stores, results showed that SOCE was increased 15-25% by dexamethasone and that this response to dexamethasone was inhibited by the store-operated calcium channel blocker BTP2. Dexamethasone treatment stimulated the activity of calcium-independent phospholipase A(2) (iPLA(2)), and dexamethasone-induced increase in SOCE was reduced by the iPLA(2) inhibitor bromoenol lactone (BEL). In additional experiments, treatment of myotubes with the store-operated calcium channel inhibitor gadolinium ion or BEL reduced dexamethasone-induced increase in protein degradation. Taken together, the results suggest that glucocorticoids increase calcium concentrations in myocytes and stimulate iPLA(2)-dependent SOCE and that glucocorticoid-induced muscle protein degradation may at least in part be regulated by increased iPLA(2) activity, SOCE, and cellular calcium levels.
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Affiliation(s)
- Kiyoshi Itagaki
- Dept. of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
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Lei X, Barbour SE, Ramanadham S. Group VIA Ca2+-independent phospholipase A2 (iPLA2beta) and its role in beta-cell programmed cell death. Biochimie 2010; 92:627-37. [PMID: 20083151 DOI: 10.1016/j.biochi.2010.01.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2009] [Accepted: 01/11/2010] [Indexed: 01/09/2023]
Abstract
Activation of phospholipases A(2) (PLA(2)s) leads to the generation of biologically active lipid mediators that can affect numerous cellular events. The Group VIA Ca(2+)-independent PLA(2), designated iPLA(2)beta, is active in the absence of Ca(2+), activated by ATP, and inhibited by the bromoenol lactone suicide inhibitor (BEL). Over the past 10-15 years, studies using BEL have demonstrated that iPLA(2)beta participates in various biological processes and the recent availability of mice in which iPLA(2)beta expression levels have been genetically-modified are extending these findings. Work in our laboratory suggests that iPLA(2)beta activates a unique signaling cascade that promotes beta-cell apoptosis. This pathway involves iPLA(2)beta dependent induction of neutral sphingomyelinase, production of ceramide, and activation of the intrinsic pathway of apoptosis. There is a growing body of literature supporting beta-cell apoptosis as a major contributor to the loss of beta-cell mass associated with the onset and progression of Type 1 and Type 2 diabetes mellitus. This underscores a need to gain a better understanding of the molecular mechanisms underlying beta-cell apoptosis so that improved treatments can be developed to prevent or delay the onset and progression of diabetes mellitus. Herein, we offer a general review of Group VIA Ca(2+)-independent PLA(2) (iPLA(2)beta) followed by a more focused discussion of its participation in beta-cell apoptosis. We suggest that iPLA(2)beta-derived products trigger pathways which can lead to beta-cell apoptosis during the development of diabetes.
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Affiliation(s)
- Xiaoyong Lei
- Department of Medicine, Mass Spectrometry Resource and Division of Endocrinology, Metabolism, and Lipid Research, Washington University School of Medicine, St. Louis, MO 63110, USA
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