101
|
Stress-induced cell death is mediated by ceramide synthesis in Neurospora crassa. EUKARYOTIC CELL 2008; 7:2147-59. [PMID: 18952903 DOI: 10.1128/ec.00147-08] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The combined stresses of moderate heat shock (45 degrees C) and analog-induced glucose deprivation constitute a lethal stress for Neurospora crassa. We found that this cell death requires fatty acid synthesis and the cofactor biotin. In the absence of the cofactor, the stressed cells are particularly sensitive to exogenous ceramide, which is lethal at low concentrations. When we extracted endogenous sphingolipids, we found that unique ceramides were induced (i) by the inhibitory glucose analog 2-deoxyglucose and (ii) by combined heat shock and 2-deoxyglucose. We determined that the former is a 2-deoxyglucose-modified ceramide. By structural analysis, we identified the latter, induced by dual stress, as C(18)(OH)-phytoceramide. We also identified C(24)(OH)-phytoceramide as a constitutive ceramide that continues to be produced during the combined stresses. The unusual C(18)(OH)-phytoceramide is not made by germinating asexual spores subjected to the same heat and carbon stress. Since these spores, unlike growing cells, do not die from the stresses, this suggests a possible connection between synthesis of the dual-stress-induced ceramide and cell death. This connection is supported by the finding that a (dihydro)ceramide synthase inhibitor, australifungin, renders cells resistant to death from these stresses. The OS-2 mitogen-activated protein kinase, homologous to mammalian p38, may be involved in the cell death signaling pathway. Strains lacking OS-2 survived the combined stresses better than the wild type, and phosphorylated OS-2 increased in wild-type cells in response to heat shock and combined heat and carbon stress.
Collapse
|
102
|
Acetyl-l-carnitine suppresses apoptosis of thioredoxin 2-deficient DT40 cells. Arch Biochem Biophys 2008; 478:154-60. [DOI: 10.1016/j.abb.2008.07.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2008] [Revised: 07/30/2008] [Accepted: 07/31/2008] [Indexed: 11/23/2022]
|
103
|
Acid Sphingomyelinase Overexpression Enhances the Antineoplastic Effects of Irradiation In Vitro and In Vivo. Mol Ther 2008; 16:1565-71. [DOI: 10.1038/mt.2008.145] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
|
104
|
Ruckhäberle E, Karn T, Hanker L, Gätje R, Metzler D, Holtrich U, Kaufmann M, Rody A. Prognostic relevance of glucosylceramide synthase (GCS) expression in breast cancer. J Cancer Res Clin Oncol 2008; 135:81-90. [PMID: 18560890 DOI: 10.1007/s00432-008-0436-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2008] [Accepted: 06/03/2008] [Indexed: 12/14/2022]
Abstract
PURPOSE Multidrug resistance (MDR) has been linked to sphingolipid metabolism and preclinical data ascribe glucosylceramide synthase (GCS) a major role for MDR especially in breast cancer cells but no profound data are available on the expression of this potential therapeutic target in clinical breast cancer specimens. METHODS We analyzed microarray data of GCS expression in a large cohort of 1,681 breast tumors. RESULTS Expression of GCS was associated with a positive estrogen receptor (ER) status, lower histological grading, low Ki67 levels and ErbB2 negativity (P < 0.001 for all). In univariate analysis there was a benefit for disease free survival for patients with tumors displaying low levels of GCS expression but this significance was lost in multivariate Cox regression. CONCLUSIONS Our results suggest ER positive tumors may be the most promising candidates for a potential therapeutic application of GCS inhibitors.
Collapse
MESH Headings
- Adolescent
- Adult
- Aged
- Aged, 80 and over
- Biomarkers, Tumor/genetics
- Biomarkers, Tumor/metabolism
- Breast Neoplasms/enzymology
- Breast Neoplasms/genetics
- Breast Neoplasms/pathology
- Carcinoma, Ductal, Breast/enzymology
- Carcinoma, Ductal, Breast/genetics
- Carcinoma, Ductal, Breast/secondary
- Carcinoma, Lobular/enzymology
- Carcinoma, Lobular/genetics
- Carcinoma, Lobular/secondary
- Cell Proliferation
- Child
- Female
- Gene Expression Profiling
- Glucosyltransferases/genetics
- Glucosyltransferases/metabolism
- Humans
- Ki-67 Antigen/genetics
- Ki-67 Antigen/metabolism
- Middle Aged
- Oligonucleotide Array Sequence Analysis
- Prognosis
- Receptor, ErbB-2/genetics
- Receptor, ErbB-2/metabolism
- Receptors, Estrogen/genetics
- Receptors, Estrogen/metabolism
- Survival Rate
- Young Adult
Collapse
Affiliation(s)
- Eugen Ruckhäberle
- Department of Gynecology, J. W. Goethe-University, Frankfurt, Germany
| | | | | | | | | | | | | | | |
Collapse
|
105
|
Charruyer A, Bell SM, Kawano M, Douangpanya S, Yen TY, Macher BA, Kumagai K, Hanada K, Holleran WM, Uchida Y. Decreased ceramide transport protein (CERT) function alters sphingomyelin production following UVB irradiation. J Biol Chem 2008; 283:16682-92. [PMID: 18411267 DOI: 10.1074/jbc.m800799200] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Increased cellular ceramide accounts in part for UVB irradiation-induced apoptosis in cultured human keratinocytes with concurrent increased glucosylceramide but not sphingomyelin generation in these cells. Given that conversion of ceramide to non-apoptotic metabolites such as sphingomyelin and glucosylceramide protects cells from ceramide-induced apoptosis, we hypothesized that failed up-regulation of sphingomyelin generation contributes to ceramide accumulation following UVB irradiation. Because both sphingomyelin synthase and glucosylceramide synthase activities were significantly decreased in UVB-irradiated keratinocytes, we investigated whether alteration(s) in the function of ceramide transport protein (or CERT) required for sphingomyelin synthesis occur(s) in UVB-irradiated cells. Fluorescently labeled N-(4,4-difluoro-5,7-dimethyl-4-bora-3a,4a-diaza-s-indacene-3-pentanoyl)-d-erythro-sphingosine (C(5)-DMB-ceramide) relocation to the Golgi was diminished after irradiation, consistent with decreased CERT function, whereas the CERT inhibitor N-(3-hydroxy-1-hydroxymethyl-3-phenylpropyl)dodecanamide (1R,3R isomer) (HPA-12) produced an equivalent effect. UVB irradiation also induced the rapid formation of a stable CERT homotrimer complex in keratinocytes as determined by Western immunoblot and mass spectrometry analyses, a finding replicated in HeLa, HEK293T, and HaCaT cells and in murine epidermis. Ceramide binding activity was decreased in recombinant CERT proteins containing the UVB-induced homotrimer. The middle region domain of the CERT protein was required for the homotrimer formation, whereas neither the pleckstrin homology (Golgi-binding) nor the START (ceramide-binding) domains were involved. Finally like UVB-treated keratinocytes, HPA-12 blockade of CERT function increased keratinocyte apoptosis, decreased sphingomyelin synthesis, and led to accumulation of ceramide. Thus, UVB-induced CERT homotrimer formation accounts, at least in part, for apoptosis and failed up-regulation of sphingomyelin synthesis following UVB irradiation, revealing that inactive CERT can attenuate a key metabolic protective mechanism against ceramide-induced apoptosis in keratinocytes.
Collapse
Affiliation(s)
- Alexandra Charruyer
- Department of Dermatology, School of Medicine, University of California, Northern California Institute for Research and Education, and Veterans Affairs Medical Center, San Francisco, California 94121, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
106
|
Liu YY, Yu JY, Yin D, Patwardhan GA, Gupta V, Hirabayashi Y, Holleran WM, Giuliano AE, Jazwinski SM, Gouaze-Andersson V, Consoli DP, Cabot MC. A role for ceramide in driving cancer cell resistance to doxorubicin. FASEB J 2008; 22:2541-51. [PMID: 18245173 DOI: 10.1096/fj.07-092981] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Advanced cancers acquire resistance to chemotherapy, and this results in treatment failure. The cellular mechanisms of chemotherapy resistance are not well understood. Here, for the first time, we show that ceramide contributes to cellular resistance to doxorubicin through up-regulating the gene expression of glucosylceramide synthase (GCS). Ceramide, a cellular lipid messenger, modulates doxorubicin-induced cell death. GCS catalyzes ceramide glycosylation, converting ceramide to glucosylceramide; this process hastens ceramide clearance and limits ceramide-induced apoptosis. In the present study, we evaluated the role of the GCS gene in doxorubicin resistance using several paired wild-type and drug-resistant (doxorubicin-selected) cancer cell lines, including breast, ovary, cervical, and colon. GCS was overexpressed in all drug-resistant counterparts, and suppressing GCS overexpression using antisense oligonucleotide restored doxorubicin sensitivity. Characterizing the effect mechanism showed that doxorubicin exposure increased ceramide levels, enhanced GCS expression, and imparted cellular resistance. Exogenous C(6)-ceramide and sphingomyelinase treatments mimicked the influence of doxorubicin on GCS, activating the GCS promoter and up-regulating GCS gene expression. Fumonisin B(1), an inhibitor of ceramide synthesis, significantly suppressed doxorubicin-up-regulated GCS expression. Promoter truncation, point mutation, gel-shift, and protein-DNA ELISA analysis showed that transcription factor Sp1 was essential for ceramide-induced GCS up-regulation. These data indicate that ceramide-governed GCS gene expression drives cellular resistance to doxorubicin.
Collapse
Affiliation(s)
- Yong-Yu Liu
- Department of Basic Pharmaceutical Sciences, University of Louisiana at Monroe, 700 University Ave., Monroe, LA 71209, USA.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
107
|
Glucosylceramide synthase decrease in frontal cortex of Alzheimer brain correlates with abnormal increase in endogenous ceramides: Consequences to morphology and viability on enzyme suppression in cultured primary neurons. Brain Res 2008; 1191:136-47. [DOI: 10.1016/j.brainres.2007.10.066] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2007] [Revised: 10/22/2007] [Accepted: 10/26/2007] [Indexed: 02/02/2023]
|
108
|
Devalapally H, Duan Z, Seiden MV, Amiji MM. Paclitaxel and ceramide co-administration in biodegradable polymeric nanoparticulate delivery system to overcome drug resistance in ovarian cancer. Int J Cancer 2007; 121:1830-8. [PMID: 17557285 DOI: 10.1002/ijc.22886] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The objective of this study was to overcome drug resistance upon systemic administration of combination paclitaxel (PTX) and the apoptotic signaling molecule C(6)-ceramide (CER) in biodegradable poly(ethylene oxide)-modified poly(epsilon-caprolactone (PEO-PCL) nanoparticles. Subcutaneous sensitive (wild-type) and multidrug resistant (MDR-1 positive) SKOV-3 human ovarian adenocarcinoma xenografts were established in female Nu/Nu mice. PTX and CER were administered intravenously either as a single agent or in combination in aqueous solution and in PEO-PCL nanoparticles to the tumor-bearing mice. There was significant (p< 0.05) tumor growth suppression in both wild-type SKOV-3 and multidrug resistant SKOV-3(TR) models upon single dose co-administration of PTX (20 mg/kg) and CER (100 mg/kg) in nanoparticle formulations as compared to the individual agents and administration in aqueous solutions. For instance, in SKOV-3 wild-type model, more than 4.3-fold increase (p < 0.05) in tumor growth delay and 3.6-fold (p < 0.05) increase in tumor volume doubling time (DT) were observed with the combination treatment in nanoparticles as compared to untreated animals. Similarly, 3-fold increase (p < 0.05) in tumor growth delay and tumor volume DT was observed in SKOV-3(TR) model. Body weight changes and blood cells counts were used as measures of safety and, except for an increase in platelet counts (p < 0.05) in PTX + CER treated animals, there was no difference between various treatment strategies. The results of this study show that combination of PTX and CER in biodegradable polymeric nanoparticles can serve as a very effective therapeutic strategy to overcome drug resistance in ovarian cancer.
Collapse
Affiliation(s)
- Harikrishna Devalapally
- Department of Pharmaceutical Sciences, School of Pharmacy, Northeastern University, Boston, MA 02115, USA
| | | | | | | |
Collapse
|
109
|
Xie P, Shen YF, Shi YP, Ge SM, Gu ZH, Wang J, Mu HJ, Zhang B, Qiao WZ, Xie KM. Overexpression of glucosylceramide synthase in associated with multidrug resistance of leukemia cells. Leuk Res 2007; 32:475-80. [PMID: 17709137 DOI: 10.1016/j.leukres.2007.07.006] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2007] [Revised: 07/05/2007] [Accepted: 07/06/2007] [Indexed: 11/27/2022]
Abstract
Ceramide, as a second messenger, initiates one of the major signal transduction pathways in tumor apoptosis. Glucosylceramide synthase (GCS) catalyzes glycosylation of ceramide and produces glucosylceramide. Through GCS, ceramide glycosylation allows cellular escape from ceramide-induced programmed cell death. Here we investigated the expression of GCS in human leukemia cells and an association between GCS and multidrug resistance of leukemia cells. Using RT-PCR technique the level of GCS gene was detected in 65 clinical multidrug resistance/non-resistance cases with leukemia, and in K562 and K562/A02 cell lines. AlamarBlue Assay was applied to confirm the multidrug resistant of K562/A02 cells. PPMP, which is a chemical inhibitor for GCS, was used to determine the relationship between GCS and drug-resistance in K562/A02 cells. In addition, multidrug resistance gene (mdr1), Bcl-2 and Bax mRNA was also analyzed by RT-PCR. The expression of GCS and mdr1 mRNA in clinic multidrug resistance samples exhibited significantly increased compared with clinic drug sensitive group (P<0.05). There was the positive correlation both the expression of GCS and mdr1 genes in leukemia samples (P<0.01, gamma=0.7). AlamarBlue Assay showed that the K562/A02 cell line was 115-fold more resistant to adriamycin and 36-fold more resistant to vincristine compared with drug-sensitive K562 cell line. There also was significant expression difference of GCS and mdr1 genes between K562 and K562/A02 cells. Bcl-2 gene exhibited higher expressions whatever in clinic drug-resistance samples or K562/A02 cells, whereas the expressions of Bax gene were higher in drug-sensitive samples and K562 cells. PPMP increased sensitivity to adriamycin toxicity by inhibiting GCS in K562/A02 cells. Therefore, it is suggested that a high level of GCS in leukemia is possible contributed to multidrug resistance of leukemia cells. Abnormally expressions of the genes in associated with cell apoptosis might be one of the main molecular pathology mechanisms of multidrug resistance caused by GCS gene.
Collapse
Affiliation(s)
- Ping Xie
- Central Laboratory, No. 1 Hospital of Wuxi, Wuxi, Jiangsu 214002, China.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
110
|
Saito M, Horikawa M, Iwamori Y, Sakakihara Y, Mizuguchi M, Igarashi T, Fujiki Y, Iwamori M. Alterations in the molecular species of plasmalogen phospholipids and glycolipids due to peroxisomal dysfunction in Chinese hamster ovary-mutant Z65 cells by FABMS method. J Chromatogr B Analyt Technol Biomed Life Sci 2007; 852:367-73. [PMID: 17383243 DOI: 10.1016/j.jchromb.2007.01.048] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2006] [Revised: 01/24/2007] [Accepted: 01/28/2007] [Indexed: 10/23/2022]
Abstract
Changes in the molecular species of lipids associated with Pex2 gene-mutation were investigated to elucidate the pathogeneses of peroxisome biogenesis disorders. Although no differences were observed in the concentrations of cholesterol and phosphatidyl choline between mutated Z65 and control CHO-K1 cells, the amounts of cholesterol esters and glycolipids in Z65 cells were twice those in CHO-K1 cells, but phosphatidyl ethanolamine (PE), particularly 1-O-octadec-1'-enyl-2-oleoyl PE, was absent in Z65 cells by FABMS. Enhanced synthesis of glycolipids in Z65 cells was associated with an abundance of lignoceric acid-containing ones, suggesting a role of glycolipids in the retention of longer saturated fatty acids.
Collapse
Affiliation(s)
- Makiko Saito
- Department of Pediatrics, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
| | | | | | | | | | | | | | | |
Collapse
|
111
|
Baritaki S, Apostolakis S, Kanellou P, Dimanche-Boitrel MT, Spandidos DA, Bonavida B. Reversal of tumor resistance to apoptotic stimuli by alteration of membrane fluidity: therapeutic implications. Adv Cancer Res 2007; 98:149-90. [PMID: 17433910 DOI: 10.1016/s0065-230x(06)98005-1] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
In recent years, significant development and improvement have been observed in the treatment of cancer; however, relapses and recurrences occur frequently and there have not been any current therapies to treat such cancers. Cancers resistant to conventional therapies develop several mechanisms to escape death-inducing stimuli. A poorly understood mechanism is the involvement of the cancer cell plasma membrane composition and architecture and their involvement in regulating drug-inducing stimuli leading to cell death. Although the basic structure of the biological membrane was established 80 years ago, study of the physical properties of lipid bilayers still provides significant information regarding membrane organization and dynamics. Membrane fluidity is probably the most important physicochemical property of cell membranes. Alterations of membrane fluidity can seriously affect functional properties of the cell and induction of apoptotic pathways resulting in cell death. The role of membrane fluidity in the apoptotic process is clearly exemplified as it is seriously disrupted as a result of cell injury. The molecular signaling pathways leading to apoptosis are currently promising areas of research investigation and lead to unravel the underlying molecular mechanisms of tumor cells resistance to apoptotic stimuli and hence the development of new effective therapeutic agents. Recent findings indicate that most anticancer agents induce apoptosis, directly or indirectly, through alterations of tumor cell membrane fluidity. The present chapter summarizes the relationship between alterations of tumor cell membrane fluidity and tumor cell response to apoptotic-inducing stimuli. Several potential therapeutic applications directed at tumor cell membrane fluidity are proposed.
Collapse
Affiliation(s)
- Stavroula Baritaki
- Department of Microbiology, Immunology, and Molecular Genetics, Jonsson Comprehensive Cancer Center, David Geffen School of Medicine at UCLA, University of California, Los Angeles, California 90095, USA
| | | | | | | | | | | |
Collapse
|
112
|
Kiguchi K, Iwamori Y, Suzuki N, Kobayashi Y, Ishizuka B, Ishiwata I, Kita T, Kikuchi Y, Iwamori M. Characteristic expression of globotriaosyl ceramide in human ovarian carcinoma-derived cells with anticancer drug resistance. Cancer Sci 2006; 97:1321-6. [PMID: 16995873 PMCID: PMC11159370 DOI: 10.1111/j.1349-7006.2006.00326.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The transporter protein genes and lipids in human ovarian carcinoma-derived KF28 cells with anticancer-drug-sensitive properties were compared with those in resistant cells, taxol-resistant KF28TX, cisplatin-resistant KFr13, and taxol- and cisplatin-resistant KFr13TX, to identify the molecules required for anticancer-drug resistance. In accordance with previous reports, taxol and cisplatin resistance was closely correlated with expression of the multidrug resistance 1 and bile acid export pump, and multidrug resistance-associated protein 2 genes, respectively. In addition, we found a distinct difference in glycosphingolipids between the sensitive and resistant cells. Although GlcCer was the major glycolipid (83.0%) in sensitive cells, GalCer, LacCer and, particularly, Gb(3)Cer were characteristically increased in all resistant cells, irrespective of whether the resistance was to taxol or cisplatin, and comprised 65-84% of total glycosphingolipids. GM3, which was present at 0.04 microg/mg dry weight in the sensitive cells, showed a twofold increase in the taxol-resistant cells, but was absent in the cisplatin-resistant cells. The altered glycolipid composition was proven to be due to enhanced or suppressed expression of the respective sugar transferase genes. In addition, the ceramide moiety of ceramide monohexoside in the sensitive cells constituted 83% of non-hydroxy fatty acids, but that in the resistant cells comprised 67-74% of alpha-hydroxy fatty acids. Thus, cells containing Gb(3)Cer with alpha-hydroxy fatty acids were found to survive selectively in the presence of taxol and cisplatin, and modification of the glycolipid structure was revealed to occur in association with anticancer-drug resistance.
Collapse
Affiliation(s)
- Kazushige Kiguchi
- Department of Obstetrics and Gynecology, St Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
113
|
Gouaze-Andersson V, Cabot MC. Glycosphingolipids and drug resistance. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2006; 1758:2096-103. [PMID: 17010304 DOI: 10.1016/j.bbamem.2006.08.012] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2006] [Revised: 08/23/2006] [Accepted: 08/23/2006] [Indexed: 01/31/2023]
Abstract
Drug resistance, an all too frequent characteristic of cancer, represents a serious barrier to successful treatment. Although many resistance mechanisms have been described, those that involve membrane-resident proteins belonging to the ABC (ATP binding cassette) transporter superfamily are of particular interest. In addition to cancer, the ABC transporter proteins are active in diseases such as malaria and leishmaniasis. A recent renaissance in lipid metabolism, specifically ceramide and sphingolipids, has fueled research and provided insight into the role of glycosphingolipids in multidrug resistance. This article reviews current knowledge on ceramide, glucosylceramide synthase and cerebrosides, and the relationship of these lipids to cellular response to anticancer agents.
Collapse
Affiliation(s)
- Valerie Gouaze-Andersson
- Department of Experimental Therapeutics, The John Wayne Cancer Institute at Saint John's Health Center, 2200 Santa Monica Blvd., Santa Monica, CA 90404, USA
| | | |
Collapse
|
114
|
Curfman CL, Kirkland K, Merrill AH. Recent anticancer agents targeting sphingolipid pathways. Expert Opin Ther Pat 2006. [DOI: 10.1517/13543776.16.8.1129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
115
|
Ségui B, Andrieu-Abadie N, Jaffrézou JP, Benoist H, Levade T. Sphingolipids as modulators of cancer cell death: potential therapeutic targets. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2006; 1758:2104-20. [PMID: 16925980 DOI: 10.1016/j.bbamem.2006.05.024] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2006] [Revised: 05/04/2006] [Accepted: 05/06/2006] [Indexed: 02/07/2023]
Abstract
Through modifications in the fine membrane structure, cell-cell or cell-matrix interactions, and/or modulation of intracellular signaling pathways, sphingolipids can affect the tumorigenic potential of numerous cell types. Whereas ceramide and its metabolites have been described as regulators of cell growth and apoptosis, these lipids as well as other sphingolipid molecules can modulate the ability of malignant cells to grow and resist anticancer treatments, and their susceptibility to non-apoptotic cell deaths. This review summarizes our current knowledge on the properties of sphingolipids in the regulation of cancer cell death and tumor development. It also provides an update on the potential perspectives of manipulating sphingolipid metabolism and using sphingolipid analogues in anticancer therapy.
Collapse
Affiliation(s)
- Bruno Ségui
- INSERM U.466, Laboratoire de Biochimie, Institut Louis Bugnard, Centre Hospitalier Universitaire de Rangueil, BP 84225, 31432 Toulouse Cedex 4, France
| | | | | | | | | |
Collapse
|
116
|
Chan SYV, Hilchie AL, Brown MG, Anderson R, Hoskin DW. Apoptosis induced by intracellular ceramide accumulation in MDA-MB-435 breast carcinoma cells is dependent on the generation of reactive oxygen species. Exp Mol Pathol 2006; 82:1-11. [PMID: 16624283 DOI: 10.1016/j.yexmp.2006.03.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2006] [Revised: 02/28/2006] [Accepted: 03/01/2006] [Indexed: 10/24/2022]
Abstract
Strategies to promote intracellular ceramide accumulation in cancer cells may have therapeutic utility because ceramide is an important second messenger during apoptosis. Exposure to cell-permeable C(6) ceramide or tricyclodecan-9-yl-xanthate (an inducer of de novo ceramide synthesis and an inhibitor of sphingomyelin synthase) caused MDA-MB-435 human breast carcinoma cells to die by apoptosis. Concomitant treatment with the ceramidase inhibitor D-erythro-2-(N-myristoylamino)-1-phenyl-1-propanol (MAPP) or the glucosylceramide synthase inhibitor 1-phenyl-2-palmitoylamino-3-morpholino-1-propanol (PPMP) potentiated the cytotoxic effect of C(6) ceramide, indicating that C(6) ceramide-mediated cytotoxicity was antagonized by the action of ceramidases and glucosylceramide synthase. Interestingly, treatment with PPMP alone, but not MAPP alone, also induced apoptosis in MDA-MB-435 cells, suggesting that conversion to glucosylceramide rather than catabolism by ceramidases prevented endogenous ceramide from reaching cytotoxic levels. C(6) ceramide-induced apoptosis in MDA-MB-435 cells was associated with the generation of reactive oxygen species, and was inhibited by the antioxidants N-acetylcysteine and glutathione. Although mitochondrial membrane integrity was disrupted in C(6) ceramide-treated MDA-MB-435 cells, apoptosis was not mediated by caspases because there was no protective effect by the pan-caspase inhibitor z-VAD-fmk. Collectively, these findings indicate that strategies to enhance intracellular ceramide accumulation in malignant cells might offer a novel approach to the treatment of breast cancer.
Collapse
Affiliation(s)
- S Y Velda Chan
- Department of Pathology, Faculty of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada B3H 1X5
| | | | | | | | | |
Collapse
|
117
|
Prinetti A, Millimaggi D, D'Ascenzo S, Clarkson M, Bettiga A, Chigorno V, Sonnino S, Pavan A, Dolo V. Lack of ceramide generation and altered sphingolipid composition are associated with drug resistance in human ovarian carcinoma cells. Biochem J 2006; 395:311-8. [PMID: 16356169 PMCID: PMC1422777 DOI: 10.1042/bj20051184] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
PTX (Paclitaxel) is an antimitotic agent used in the treatment of a number of major solid tumours, particularly in breast and ovarian cancer. This study was undertaken to gain insight into the molecular alterations producing PTX resistance in ovarian cancer. PTX treatment is able to induce apoptosis in the human ovarian carcinoma cell line, CABA I. PTX-induced apoptosis in CABA I cells was accompanied by an increase in the cellular Cer (ceramide) levels and a decrease in the sphingomyelin levels, due to the activation of sphingomyelinases. The inhibition of acid sphingomyelinase decreased PTX-induced apoptosis. Under the same experimental conditions, PTX had no effect on Cer and sphingomyelin levels in the stable PTX-resistant ovarian carcinoma cell line, CABA-PTX.The acquisition of the PTX-resistant phenotype is accompanied by unique alterations in the complex sphingolipid pattern found on lipid extraction. In the drug-resistant cell line, the levels of sphingomyelin and neutral glycosphingolipids were unchanged compared with the drug-sensitive cell line. The ganglioside pattern in CABA I cells is more complex compared with that of CABA-PTX cells. Specifically, we found that the total ganglioside content in CABA-PTX cells was approximately half of that in CABA I cells, and GM3 ganglioside content was remarkably higher in the drug-resistant cell line. Taken together our findings indicate that: i) Cer generated by acid sphingomyelinase is involved in PTX-induced apoptosis in ovarian carcinoma cells, and PTX-resistant cells are characterized by their lack of increased Cer upon drug treatment, ii) PTX resistance might be correlated with an alteration in metabolic Cer patterns specifically affecting cellular ganglioside composition.
Collapse
Affiliation(s)
- Alessandro Prinetti
- *Centre of Excellence for Neurodegenerative Disease, Department of Medical Chemistry, Biochemistry and Biotechnology, University of Milan, 20090 Segrate, Italy
| | - Danilo Millimaggi
- †Department of Experimental Medicine, University of L'Aquila, 67100 L'Aquila, Italy
| | - Sandra D'Ascenzo
- †Department of Experimental Medicine, University of L'Aquila, 67100 L'Aquila, Italy
| | - Matilda Clarkson
- †Department of Experimental Medicine, University of L'Aquila, 67100 L'Aquila, Italy
| | - Arianna Bettiga
- *Centre of Excellence for Neurodegenerative Disease, Department of Medical Chemistry, Biochemistry and Biotechnology, University of Milan, 20090 Segrate, Italy
| | - Vanna Chigorno
- *Centre of Excellence for Neurodegenerative Disease, Department of Medical Chemistry, Biochemistry and Biotechnology, University of Milan, 20090 Segrate, Italy
| | - Sandro Sonnino
- *Centre of Excellence for Neurodegenerative Disease, Department of Medical Chemistry, Biochemistry and Biotechnology, University of Milan, 20090 Segrate, Italy
| | - Antonio Pavan
- †Department of Experimental Medicine, University of L'Aquila, 67100 L'Aquila, Italy
| | - Vincenza Dolo
- †Department of Experimental Medicine, University of L'Aquila, 67100 L'Aquila, Italy
- To whom correspondence should be addressed (email )
| |
Collapse
|
118
|
Ozben T. Mechanisms and strategies to overcome multiple drug resistance in cancer. FEBS Lett 2006; 580:2903-9. [PMID: 16497299 DOI: 10.1016/j.febslet.2006.02.020] [Citation(s) in RCA: 292] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2006] [Accepted: 02/09/2006] [Indexed: 10/25/2022]
Abstract
One of the major problems in chemotherapy is multidrug resistance (MDR) against anticancer drugs. ATP-binding cassette (ABC) transporters are a family of proteins that mediate MDR via ATP-dependent drug efflux pumps. Many MDR inhibitors have been identified, but none of them have been proven clinically useful without side effects. Efforts continue to discover not toxic MDR inhibitors which lack pharmacokinetic interactions with anticancer drugs. Novel approaches have also been designed to inhibit or circumvent MDR. In this review, the structure and function of ABC transporters and development of MDR inhibitors are described briefly including various approaches to suppress MDR mechanisms.
Collapse
Affiliation(s)
- Tomris Ozben
- Akdeniz University, Faculty of Medicine, Department of Biochemistry, 07070 Antalya, Turkey.
| |
Collapse
|
119
|
Faugeroux V, Génisson Y, Andrieu-Abadie N, Colié S, Levade T, Baltas M. C-Alkyl 5-membered ring imino sugars as new potent cytotoxic glucosylceramide synthase inhibitors. Org Biomol Chem 2006; 4:4437-9. [PMID: 17268635 DOI: 10.1039/b613460b] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The stereoselective preparation of novel C-alkyl 5-membered ring imino sugars and their biological evaluation with regard to GCS inhibition and cytotoxicity in a murine melanoma model are reported.
Collapse
Affiliation(s)
- Vanessa Faugeroux
- Laboratoire de Synthèse et Physicochimie de Molécules d'Intérêt Biologique, UMR 5068CNRS/Université Paul Sabatier, 118 route de Narbonne, 31062, Toulouse Cedex 9, France
| | | | | | | | | | | |
Collapse
|
120
|
Hinrichs JWJ, Klappe K, van Riezen M, Kok JW. Drug resistance-associated changes in sphingolipids and ABC transporters occur in different regions of membrane domains. J Lipid Res 2005; 46:2367-76. [PMID: 16150833 DOI: 10.1194/jlr.m500070-jlr200] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We have recently shown that two ATP binding cassette (ABC) transporters are enriched in Lubrol-resistant noncaveolar membrane domains in multidrug-resistant human cancer cells [Hinrichs, J. W. J., K. Klappe, I. Hummel, and J. W. Kok. 2004. ATP-binding cassette transporters are enriched in non-caveolar detergent-insoluble glycosphingolipid-enriched membrane domains (DIGs) in human multidrug-resistant cancer cells. J. Biol. Chem. 279: 5734-5738]. Here, we show that aminophospholipids are relatively enriched in Lubrol-resistant membrane domains compared with Triton X-100-resistant membrane domains, whereas sphingolipids are relatively enriched in the latter. Moreover, Lubrol-resistant membrane domains contain more protein and lipid mass. Based on these results, we postulate a model for detergent-insoluble glycosphingolipid-enriched membrane domains consisting of a Lubrol-insoluble/Triton X-100-insoluble region and a Lubrol-insoluble/Triton X-100-soluble region. The latter region contains most of the ABC transporters as well as lipids known to be necessary for their efflux activity. Compared with drug-sensitive cells, the detergent-insoluble glycosphingolipid-enriched membrane domains (DIGs) in drug-resistant cells differ specifically in sphingolipid content and not in protein, phospholipid, or cholesterol content. In drug-resistant cells, sphingolipids with specific fatty acids (especially C24:1) are enriched in these membrane domains. Together, these data show that multidrug resistance-associated changes in both sphingolipids and ABC transporters occur in DIGs, but in different regions of these domains.
Collapse
Affiliation(s)
- John W J Hinrichs
- Department of Cell Biology, Section of Membrane Cell Biology, University Medical Center Groningen, Groningen, The Netherlands
| | | | | | | |
Collapse
|
121
|
Saito K, Takakuwa N, Ohnishi M, Oda Y. Presence of glucosylceramide in yeast and its relation to alkali tolerance of yeast. Appl Microbiol Biotechnol 2005; 71:515-21. [PMID: 16228202 DOI: 10.1007/s00253-005-0187-3] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2005] [Revised: 09/05/2005] [Accepted: 09/07/2005] [Indexed: 11/28/2022]
Abstract
Glycosylceramide is a membrane lipid that has physiological functions in eukaryotic organisms. The presence of glucosylceramide has been confirmed in some yeast; however, the extent of the role of glucosylceramide in yeast is unknown. Thus, the extent of presence of glucosylceramide in yeast was surveyed using 90 strains of 24 genera. The strains were divided into two groups according to whether they had glucosylceramide (45 strains) or not (45 strains). The distribution of the ceramide glucosyltransferase gene (EC 2.4.1.80), which catalyzes glucosylation to a sphingoid lipid in glucosylceramide synthesis, and the phylogenetic classification of the strains were in agreement with those of glucosylceramide. Thus, the presence of glucosylceramide in yeast was caused by the presence of the gene involved in glucosylceramide synthesis and was closely associated with yeast evolution. Furthermore, the relationship between glucosylceramide presence and alkali tolerance of yeast was evaluated. The yeast with glucosylceramide tended to grow at higher pH, and a ceramide-glucosyltransferase-defective mutant from Kluyveromyces lactis did not grow at pH 8.5 even though the parent strain could grow under the same conditions. These results indicate that glucosylceramide in yeast might be a component that enables yeast to grow under alkali conditions.
Collapse
Affiliation(s)
- Katsuichi Saito
- Department of Upland Agriculture, National Agricultural Research Center for Hokkaido Region, Memuro, Kasai, Hokkaido, 082-0071, Japan.
| | | | | | | |
Collapse
|
122
|
Aouali N, Eddabra L, Macadré J, Morjani H. Immunosuppressors and reversion of multidrug-resistance. Crit Rev Oncol Hematol 2005; 56:61-70. [PMID: 15978826 DOI: 10.1016/j.critrevonc.2004.12.010] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2004] [Revised: 11/30/2004] [Accepted: 12/10/2004] [Indexed: 11/25/2022] Open
Abstract
Drug resistance is the major reason for failure of cancer therapy. When one drug elicits a response in tumour cells resulting in resistance to a large variety of chemically unrelated drugs, this is called multidrug-resistance (MDR). ATP-binding cassette (ABC) transporters contribute to drug resistance via ATP-dependent drug efflux. P-glycoprotein (Pgp) encoded by MDR1 gene, confers resistance to certain anticancer agents. The development of agents able to modulate MDR mediated by Pgp and ABC transporters remained a major goal for the past 10 years. Immunosuppressors, cyclosporin A (CSA) in particular, were shown to modulate Pgp activity in laboratory models and entered very early into clinical trials for reversal of MDR. The proof of reversing activity of CSA was found in phase II studies with myeloma and acute leukaemia. In phase III studies, the results were less convincing regarding the response rate, progression-free survival and overall survival were detected in advanced refractory myeloma. The non-immunosuppressive derivative PSC833 was then extensively studied. This compound shows 10-fold higher potency in reversal of MDR mediated by Pgp. Results from clinical trials with this modulator are still emerging and the notable finding was the need to reduce the dose of anticancer agent used in combination with it. Other effects of CSA and PSC833 on MDR have been described. These two molecules have been shown to have an action on the metabolism of ceramide which stands as second messenger of anticancer agents-induced apoptosis. PSC833 stimulates de novo ceramide synthesis and enhances cell death induced by anticancer agents, such as camptothecins and anthracyclines. In addition, ceramide glycosylation and storage in some cell lines have been described to play a crucial role in resistance to anticancer drugs. CSA is able to inhibit ceramide glucosylation and modulate MDR phenotype. The emergence of other modulators with several ABC protein targets like VX710 are of clinical interest in malignancies expressing several efflux pumps.
Collapse
Affiliation(s)
- Nassera Aouali
- Roswell Park Cancer Institute, Department of Cancer Genetique, Elm and Carlton Streets, Buffalo, NY 14263, USA
| | | | | | | |
Collapse
|
123
|
Hinrichs JWJ, Klappe K, Kok JW. Rafts as missing link between multidrug resistance and sphingolipid metabolism. J Membr Biol 2005; 203:57-64. [PMID: 15981711 DOI: 10.1007/s00232-004-0733-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- J W J Hinrichs
- Groningen University Institute for Drug Exploration, Department of Membrane Cell Biology, University of Groningen, 9713 AV Groningen, The Netherlands
| | | | | |
Collapse
|
124
|
Ravindranath MH, Muthugounder S, Presser N, Ye X, Brosman S, Morton DL. Endogenous immune response to gangliosides in patients with confined prostate cancer. Int J Cancer 2005; 116:368-77. [PMID: 15818621 DOI: 10.1002/ijc.21023] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Our study investigated whether endogenous IgM antibodies to gangliosides occur in patients with early stages of prostate cancer (CaP) patients, after defining ganglioside profiles of CaP cell lines. Immune and resorcinol staining detected the presence of gangliosides GM3, GM2, GD3, GD2 and GD1a but not GM1a, GD1b or GT1b in the extracts of normal prostatic epithelial cells (PrEC) and neoplastic androgen-insensitive (PC-3, DU145) and -sensitive (LNCaP-FGC and LNCaP-FGC-10) CaP cells. Using a sensitive ELISA, developed and validated in our laboratory, the titers of IgM against 8 gangliosides from sera of patients with benign prostatic hyperplasia (BPH) (n = 11), organ-confined (T1/T2, n = 36) and unconfined (T3/T4, n = 27) CaP and age-matched healthy men (n = 11) were determined double-blinded. Using ANOVA and Fisher's least significant difference (LSD) methods, the log-titers among different groups were compared. CaP patients differed from healthy and BPH patients in increased titers against GD1a and decreased titers against GD3. Titers of antibodies to other gangliosides exhibited no difference between CaP patients and others. The specific augmentation of anti-GD1a IgM in patients with organ-confined CaP (stage T1/T2) but not in patients with unconfined CaP (stage T3/T4) or BPH or in healthy controls is striking. This finding together with identification of GD1a as a major ganglioside in CaP cell lines and with the accruing studies on the immunosuppressive nature of GD1a indicates that augmentation of anti-GD1a IgM in confined CaP may signify an early endogenous immune response to eliminate a "danger signal" from tumor microenvironment and circulation.
Collapse
Affiliation(s)
- Mepur H Ravindranath
- Laboratory of Glycoimmunotherapy, John Wayne Cancer Institute, Santa Monica, CA 90404, USA.
| | | | | | | | | | | |
Collapse
|
125
|
Hahn HP, Pang M, He J, Hernandez JD, Yang RY, Li LY, Wang X, Liu FT, Baum LG. Galectin-1 induces nuclear translocation of endonuclease G in caspase- and cytochrome c-independent T cell death. Cell Death Differ 2005; 11:1277-86. [PMID: 15297883 PMCID: PMC1201488 DOI: 10.1038/sj.cdd.4401485] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Galectin-1, a mammalian lectin expressed in many tissues, induces death of diverse cell types, including lymphocytes and tumor cells. The galectin-1 T cell death pathway is novel and distinct from other death pathways, including those initiated by Fas and corticosteroids. We have found that galectin-1 binding to human T cell lines triggered rapid translocation of endonuclease G from mitochondria to nuclei. However, endonuclease G nuclear translocation occurred without cytochrome c release from mitochondria, without nuclear translocation of apoptosis-inducing factor, and prior to loss of mitochondrial membrane potential. Galectin-1 treatment did not result in caspase activation, nor was death blocked by caspase inhibitors. However, galectin-1 cell death was inhibited by intracellular expression of galectin-3, and galectin-3 expression inhibited the eventual loss of mitochondrial membrane potential. Galectin-1-induced cell death proceeds via a caspase-independent pathway that involves a unique pattern of mitochondrial events, and different galectin family members can coordinately regulate susceptibility to cell death.
Collapse
Affiliation(s)
- Hejin P. Hahn
- Dept. of Pathology and Laboratory Medicine, UCLA School of Medicine, Los Angeles, California, USA 90095
| | - Mabel Pang
- Dept. of Pathology and Laboratory Medicine, UCLA School of Medicine, Los Angeles, California, USA 90095
| | - Jiale He
- Dept. of Pathology and Laboratory Medicine, UCLA School of Medicine, Los Angeles, California, USA 90095
| | - Joseph D. Hernandez
- Dept. of Pathology and Laboratory Medicine, UCLA School of Medicine, Los Angeles, California, USA 90095
| | - Ri-Yao Yang
- Dept. of Dermatology, UC Davis School of Medicine, Davis, California, USA 95616
| | - Lily Y. Li
- Howard Hughes Medical Institute & Dept. of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, USA 75390
| | - Xiaodong Wang
- Howard Hughes Medical Institute & Dept. of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, USA 75390
| | - Fu-Tong Liu
- Dept. of Dermatology, UC Davis School of Medicine, Davis, California, USA 95616
| | - Linda G. Baum
- Dept. of Pathology and Laboratory Medicine, UCLA School of Medicine, Los Angeles, California, USA 90095
- Correspondence should be addressed to L.G.B., Dept. of Pathology and Laboratory Medicine, UCLA School of Medicine, 10833 LeConte Ave., Los Angeles, California, USA 90095-1732, phone 310-206-5985, fax 310-206-0657,
| |
Collapse
|
126
|
Gouazé V, Liu YY, Prickett CS, Yu JY, Giuliano AE, Cabot MC. Glucosylceramide synthase blockade down-regulates P-glycoprotein and resensitizes multidrug-resistant breast cancer cells to anticancer drugs. Cancer Res 2005; 65:3861-7. [PMID: 15867385 DOI: 10.1158/0008-5472.can-04-2329] [Citation(s) in RCA: 130] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Overexpression of glucosylceramide synthase (GCS), a pivotal enzyme in glycolipid biosynthesis, contributes to cancer cell resistance to chemotherapy. We previously showed that transfection of doxorubicin-resistant MCF-7-AdrR cells with GCS antisense restored cell sensitivity to doxorubicin and greatly enhanced sensitivity to vinblastine and paclitaxel. In that study, doxorubicin promoted generation of ceramide in MCF-7-AdrR/GCS antisense cells; the present study implicates factors in addition to ceramide that augment sensitivity to chemotherapy. Although GCS antisense cells showed enhanced ceramide formation compared with MCF-7-AdrR when challenged with paclitaxel, GCS antisense cells also showed a 10-fold increase in levels of intracellular drug (paclitaxel and vinblastine). In addition, transfected cells had dramatically decreased expression (80%) of P-glycoprotein and a 4-fold decrease in the level of cellular gangliosides. Chemical inhibition of GCS produced the same effects as antisense transfection: exposure of MCF-7-AdrR cells to the GCS inhibitor 1-phenyl-2-palmitoylamino-3-morpholino-1-propanol (PPMP, 5.0 micromol/L, 4 days) decreased ganglioside levels, restored sensitivity to vinblastine, enhanced vinblastine uptake 3-fold, and diminished expression of MDR1 by 58%, compared with untreated controls. A similar effect was shown in vinblastin-resistant KB-V0.01 cells; after 7 days with PPMP (10 micromol/L), MDR1 expression fell by 84% and P-glycoprotein protein levels decreased by 50%. MCF-7-AdrR cells treated with small interfering RNAs to specifically block GCS also showed a dramatic decrease in MDR1 expression. This work shows that limiting GCS activity down-regulates the expression of MDR1, a phenomenon that may drive the chemosensitization associated with blocking ceramide metabolism. The data suggest that lipids play a role in the expression of multidrug resistance.
Collapse
MESH Headings
- ATP Binding Cassette Transporter, Subfamily B, Member 1/antagonists & inhibitors
- ATP Binding Cassette Transporter, Subfamily B, Member 1/biosynthesis
- ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics
- Adenocarcinoma/drug therapy
- Adenocarcinoma/enzymology
- Adenocarcinoma/genetics
- Adenocarcinoma/metabolism
- Breast Neoplasms/drug therapy
- Breast Neoplasms/enzymology
- Breast Neoplasms/genetics
- Breast Neoplasms/metabolism
- Cell Line, Tumor
- Down-Regulation
- Doxorubicin/pharmacology
- Drug Resistance, Multiple
- Drug Resistance, Neoplasm
- Gangliosides/metabolism
- Glucosyltransferases/antagonists & inhibitors
- Glucosyltransferases/genetics
- Humans
- Morpholines/pharmacology
- Oligonucleotides, Antisense/genetics
- Paclitaxel/pharmacology
- Sphingolipids/pharmacology
- Transfection
- Vinblastine/pharmacology
Collapse
Affiliation(s)
- Valérie Gouazé
- John Wayne Cancer Institute at Saint John's Health Center, Santa Monica, California 90404, USA
| | | | | | | | | | | |
Collapse
|
127
|
Hummel I, Klappe K, Kok JW. Up-regulation of lactosylceramide synthase in MDR1 overexpressing human liver tumour cells. FEBS Lett 2005; 579:3381-4. [PMID: 15936020 DOI: 10.1016/j.febslet.2005.05.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2005] [Revised: 04/27/2005] [Accepted: 05/02/2005] [Indexed: 10/25/2022]
Abstract
HepG2 cells, stably transfected with MDR1 cDNA, encoding the P-glycoprotein multidrug resistance efflux pump, display an altered sphingolipid composition compared to control cells, stably transfected with empty vector. The MDR1 overexpressing cells display a approximately 3-fold increased level of lactosylceramide and an increased ganglioside mass. Both the mRNA and the activity of lactosylceramide synthase were increased in HepG2/MDR1 cells. In conclusion, the increased glycolipid content in MDR1-transfected HepG2 cells is caused by a transcriptional up-regulation of the enzyme lactosylceramide synthase.
Collapse
Affiliation(s)
- Ina Hummel
- University Medical Center Groningen, Department of Cell Biology, Section Membrane Cell Biology, A. Deusinglaan 1, Bldg 3215, 10th fl, 9713 AV Groningen, The Netherlands.
| | | | | |
Collapse
|
128
|
Bieberich E. Integration of glycosphingolipid metabolism and cell-fate decisions in cancer and stem cells: review and hypothesis. Glycoconj J 2005; 21:315-27. [PMID: 15514480 DOI: 10.1023/b:glyc.0000046274.35732.47] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The metabolism of glycosphingolipids is strictly regulated during the mitotic cell cycle. Before the G1-to-S transition, the ceramide and glucosylceramide concentration is elevated. Ceramide induces apoptosis synergistically with the pro-apoptotic protein prostate apoptosis response 4 (PAR-4) that may be asymmetrically inherited during cell division. Only one daughter cell dies shortly after mitosis, a mechanism we suggested to regulate the number of neural stem cells during embryonic development. The progeny cells, however, may protect themselves by converting ceramide to glucosylceramide and other glycosphingolipids. In particular, complex gangliosides have been found to sustain cell survival and differentiation. The cell cycle may thus be a turning point for (glyco)sphingolipid metabolism and explain rapid changes of the sphingolipid composition in cells that undergo mitotic cell-fate decisions. In the proposed model termed "Shiva cycle", progression through the cell cycle, differentiation, or apoptosis may rely on a delicate balance of (glyco)sphingolipid second messengers that modulate the retinoblastoma-dependent G1-to-S transition or caspase-dependent G1-to-apoptosis program. Ceramide-induced cell cycle delay at G0/G1 is either followed by ceramide-induced apoptosis or by conversion of ceramide to glucosylceramide, a proposed key regulatory rheostat that rescues cells from re-entry into a life/death decision at G1-to-S. We propose a mechanistic model for sphingolpid-induced protein scaffolds ("slip") that regulate cell-fate decisions and will discuss the biological consequences and pharmacological potential of manipulating the (glyco)sphingolipid-dependent cell fate program in cancer and stem cells.
Collapse
Affiliation(s)
- Erhard Bieberich
- Institute of Molecular Medicine and Genetics, School of Medicine, Medical College of Georgia, 1120 15th Street Room CB-2803, Augusta, GA 30912, USA.
| |
Collapse
|
129
|
Morales A, Colell A, Mari M, Garcia-Ruiz C, Fernandez-Checa JC. Glycosphingolipids and mitochondria: role in apoptosis and disease. Glycoconj J 2005; 20:579-88. [PMID: 15454696 DOI: 10.1023/b:glyc.0000043294.62504.2c] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Glycosphingolipids (GSLs) comprise a class of lipids with important structural and signaling functions. Synthesized from ceramide in the Golgi, they are subsequently distributed to different compartments, most predominantly in the plasma membrane where they integrate signaling platforms. A recently characterized trafficking of ganglioside GD3 (GD3), a GSLs with two sialic-acid residues, to mitochondria has revealed a novel function of this lipid as a death effector. In addition to the interaction of GD3 with mitochondria recruiting these organelles to apoptotic pathways, GD3 disables survival paths dependent on NF-kappaB, thus favoring the balance towards cell death. The present review gathers the evidence documenting this emerging function of GSLs in cell death and their involvement in pathological states.
Collapse
Affiliation(s)
- Albert Morales
- Liver Unit, Instituto de Malalties Digestives, Hospital Clinic i Provincial, Instituto Investigaciones Biomédicas August Pi i Sunyer, Barcelona 08036, Spain
| | | | | | | | | |
Collapse
|
130
|
Modrak DE, Cardillo TM, Newsome GA, Goldenberg DM, Gold DV. Synergistic interaction between sphingomyelin and gemcitabine potentiates ceramide-mediated apoptosis in pancreatic cancer. Cancer Res 2005; 64:8405-10. [PMID: 15548711 DOI: 10.1158/0008-5472.can-04-2988] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We have examined the mechanism by which sphingomyelin (SM) enhances chemotherapy in human pancreatic cancer cells, focusing on the correlation between ceramide metabolism and apoptosis. Dose response curves for gemcitabine in the absence or presence of 0.2 mg/mL SM provided IC(50) values of 78.3 +/- 13.7 and 13.0 +/- 3.0 nmol/L, respectively. The cytotoxic effect of the combined treatment was synergistic (combination index = 0.36). Using annexin-V staining, the percentage of apoptotic cells was 3.6 +/- 2.6% for the untreated cells, 6.5 +/- 3.8% for the 0.2 mg/mL SM-treated cells, and 19.9 +/- 12.9% for the 100 nmol/L gemcitabine-treated cells, but increased significantly to 42.1 +/- 12.7% with the combined treatment (P < 0.001, compared with gemcitabine-treated group). The percentage of cells losing mitochondrial membrane potential followed a similar trend. The ceramide content of untreated and gemcitabine-treated cells was not significantly different (0.46 +/- 0.29 and 0.59 +/- 0.34 pmol ceramide/nmole PO(4)). However, when 0.2 mg/mL SM was added, ceramide levels were 1.09 +/- 0.42 and 1.58 +/- 0.55 pmol ceramide/nmol PO(4), for the SM alone and SM with gemcitabine-treated cells, respectively (P = 0.038). Acidic SMase was activated by exposure to gemcitabine but not SM, whereas the activities of neutral SMase and glycosylceramide synthase did not change with either gemcitabine or SM. The data are consistent with gemcitabine-induced activation of acidic SMase and indicate that the addition of SM can yield increased production of ceramide, mitochondrial depolarization, apoptosis, and cell death. Because SM by itself is relatively nontoxic, addition of this lipid to agents that induce apoptosis may prove useful to enhance apoptosis and increase cytotoxicity in cancer cells.
Collapse
Affiliation(s)
- David E Modrak
- Garden State Cancer Center, Center for Molecular Medicine and Immunology, Belleville, New Jersey 07109, USA.
| | | | | | | | | |
Collapse
|
131
|
Kasperzyk JL, d'Azzo A, Platt FM, Alroy J, Seyfried TN. Substrate reduction reduces gangliosides in postnatal cerebrum-brainstem and cerebellum in GM1 gangliosidosis mice. J Lipid Res 2005; 46:744-51. [PMID: 15687347 DOI: 10.1194/jlr.m400411-jlr200] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
II3NeuAc-GgOse4Cer (GM1) gangliosidosis is an incurable lysosomal storage disease caused by a deficiency in acid beta-galactosidase (beta-gal), resulting in the accumulation of ganglioside GM1 and its asialo derivative GgOse4Cer (GA1) in the central nervous system, primarily in the brain. In this study, we investigated the effects of N-butyldeoxygalacto-nojirimycin (N B-DGJ), an imino sugar that inhibits ganglioside biosynthesis, in normal C57BL/6J mice and in beta-gal knockout (beta-gal-/-) mice from postnatal day 9 (p-9) to p-15. This is a period of active cerebellar development and central nervous system (CNS) myelinogenesis in the mouse and would be comparable to late-stage embryonic and early neonatal development in humans. N B-DGJ significantly reduced total ganglioside and GM1 content in cerebrum-brainstem (C-BS) and in cerebellum of normal and beta-gal-/- mice. N B-DGJ had no adverse effects on body weight or C-BS/cerebellar weight, water content, or thickness of the external cerebellar granule cell layer. Sphingomyelin was increased in C-BS and cerebellum, but no changes were found for cerebroside (a myelin-enriched glycosphingolipid), neutral phospholipids, or GA1 in the treated mice. Our findings indicate that the effects of N B-DGJ in the postnatal CNS are largely specific to gangliosides and suggest that N B-DGJ may be an effective early intervention therapy for GM1 gangliosidosis and other ganglioside storage disorders.
Collapse
Affiliation(s)
- J L Kasperzyk
- Department of Biology, Boston College, Chestnut Hill, MA 02467, USA
| | | | | | | | | |
Collapse
|
132
|
Turzanski J, Grundy M, Shang S, Russell N, Pallis M. P-glycoprotein is implicated in the inhibition of ceramide-induced apoptosis in TF-1 acute myeloid leukemia cells by modulation of the glucosylceramide synthase pathway. Exp Hematol 2005; 33:62-72. [PMID: 15661399 DOI: 10.1016/j.exphem.2004.10.005] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2004] [Revised: 09/23/2004] [Accepted: 10/06/2004] [Indexed: 11/18/2022]
Abstract
OBJECTIVE Ceramide, an intermediate of apoptosis induction in response to chemotherapy, can be detoxified by glycosylation at the cytoplasmic surface of the Golgi membrane. P-glycoprotein (p-gp) might augment ceramide glycosylation by translocating glucosylceramide (GC) across the Golgi membrane. We aimed to show that glucosylceramide synthase (GCS) activity is linked to p-gp expression and resistance to ceramide-induced apoptosis in acute myeloid leukemia (AML). METHODS Apoptosis and cell-cycle analysis were measured using propidium iodide staining and flow cytometry. Fluorescent microscopy assessed p-gp expression in, and rhodamine 123 uptake by, the Golgi. P-gp interaction with GC was assessed by modulation of rhodamine accumulation. The GCS activity assay was based upon the transfer of UDP-(3)H-glucose to C8-ceramide to form radiolabeled GC, by rate-limiting cell-derived GCS. TLC and fluorimetry were used to measure the metabolites of fluorescent ceramide. Cell viability was measured using 7-amino-actinomycin D staining and flow cytometry with an internal standard for cell enumeration. RESULTS P-gp(+) cell lines (KG1a, TF-1) were resistant to C8-ceramide-induced apoptosis compared to p-gp(-) cell lines (HL-60, U937). P-gp inhibitors GF120918 and cyclosporin A enhanced ceramide-induced apoptosis in the p-gp expressing cells. P-gp expression was identified in the Golgi of these cells. Pgp's efflux function in TF-1 but not KG1a cells was inhibited by glucosylceramide. In the presence of p-gp inhibitors, R123 accumulation in the Golgi of TF-1 cells was lost, and GCS activity and lactosylceramide formation were downregulated. Intact cells were necessary for the involvement of p-gp in the regulation of GCS activity. CONCLUSION Our data suggests that ceramide induces apoptosis in AML cells and that p-gp confers resistance to ceramide-induced apoptosis, with modulation of the ceramide-glucosylceramide pathway making a marked contribution to this resistance in TF-1 cells.
Collapse
Affiliation(s)
- Julie Turzanski
- Division of Haematology, University of Nottingham and Nottingham City Hospital, Nottingham, UK
| | | | | | | | | |
Collapse
|
133
|
Pannu R, Won JS, Khan M, Singh AK, Singh I. A novel role of lactosylceramide in the regulation of lipopolysaccharide/interferon-gamma-mediated inducible nitric oxide synthase gene expression: implications for neuroinflammatory diseases. J Neurosci 2004; 24:5942-54. [PMID: 15229242 PMCID: PMC6729229 DOI: 10.1523/jneurosci.1271-04.2004] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In the present study a possible role of glycosphingolipids (GSLs) in inducible nitric oxide synthase (iNOS) gene expression and nitric oxide (NO) production after spinal cord injury (SCI) in rats has been established. In primary rat astrocytes lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma) treatment increased the intracellular levels of lactosylceramide (LacCer) and induced iNOS gene expression. d-Threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol.HCI (PDMP), a glucosylceramide synthase and LacCer synthase (galactosyltransferase, GalT-2) inhibitor, inhibited LPS/IFN-gamma induced iNOS expression, which was reversed by exogenously supplied LacCer, but not by other glycosphingolipids. LPS/IFN-gamma caused a rapid increase in the activity of GalT-2 and synthesis of LacCer. Silencing of GalT-2 gene with the use of antisense oligonucleotides resulted in decreased LPS/IFN-gamma-induced iNOS, TNF-alpha, and IL-1beta gene expression. The PDMP-mediated reduction in LacCer production and inhibition of iNOS expression correlated with decreased Ras and ERK1/2 activation along with decreased IkappaB phosphorylation, NF-kappaB DNA binding activity, and NF-kappaB-luciferase reporter activity. LacCer-mediated Ras activation was redox-mediated and was attenuated by antioxidants N-acetyl cysteine (NAC) and pyrrolidine dithiocarbamate (PDTC). In vivo administration of PDMP after SCI resulted in improved functional outcome (Basso, Beattie, Bresnahan score); inhibition of iNOS, TNF-alpha, and IL-1beta expression; decreased neuronal apoptosis; and decreased tissue necrosis and demyelination. The in vivo studies supported the conclusions drawn from cell culture studies and provided evidence for the possible role of GalT-2 and LacCer in SCI-induced inflammation and pathology. To our knowledge this is the first report of a role of LacCer in iNOS expression and the advantage of GSL depletion in attenuating post-SCI inflammation to improve the outcome of SCI.
Collapse
Affiliation(s)
- Ravinder Pannu
- Department of Pediatrics, Medical University of South Carolina, Charleston, South Carolina 29425, USA
| | | | | | | | | |
Collapse
|
134
|
Taguchi Y, Kondo T, Watanabe M, Miyaji M, Umehara H, Kozutsumi Y, Okazaki T. Interleukin-2-induced survival of natural killer (NK) cells involving phosphatidylinositol-3 kinase-dependent reduction of ceramide through acid sphingomyelinase, sphingomyelin synthase, and glucosylceramide synthase. Blood 2004; 104:3285-93. [PMID: 15271800 DOI: 10.1182/blood-2004-03-0900] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
AbstractInterleukin 2 (IL-2) rescued human natural killer (NK) KHYG-1 cells from apoptosis along with a reduction of ceramide. Conversely, an increase of ceramide inhibited IL-2-rescued survival. IL-2 deprivation-induced activation of acid sphingomyelinase (SMase) and inhibition of glucosylceramide synthase (GCS) and sphingomyelin synthase (SMS) were normalized by IL-2 supplementation. A phosphatidyl inositol-3 (PI-3) kinase inhibitor, LY294002, inhibited IL-2-rescued survival, but a mitogen-activated protein kinase inhibitor, PD98059, and an inhibitor of Janus tyrosine kinase/signal transducer and activator of transcription pathway, AG490, did not. LY294002 inhibited IL-2-induced reduction of ceramide through activation of acid SMase and inhibition of GCS and SMS, suggesting the positive involvement of PI-3 kinase in ceramide reduction through enzymatic regulation. Indeed, a constitutively active PI-3 kinase enhanced growth rate and ceramide reduction through inhibition of acid SMase and activation of GCS and SMS. Further, LY294002 inhibited IL-2-induced changes of transcriptional level as well as mRNA and protein levels in acid SMase and GCS but did not affect the stability of the mRNAs. These results suggest that PI-3 kinase-dependent reduction of ceramide through regulation of acid SMase, GCS, and SMS plays a role in IL-2-rescued survival of NK cells. (Blood. 2004;104:3285-3293)
Collapse
Affiliation(s)
- Yoshimitsu Taguchi
- Department of Hematology and Oncology, Graduate School of Medicine, Kyoto University, 54 Syogoin-Kawaramachi, Sakyo-ku, Kyoto 606-8507, Japan
| | | | | | | | | | | | | |
Collapse
|
135
|
Uchida Y, Itoh M, Taguchi Y, Yamaoka S, Umehara H, Ichikawa SI, Hirabayashi Y, Holleran WM, Okazaki T. Ceramide reduction and transcriptional up-regulation of glucosylceramide synthase through doxorubicin-activated Sp1 in drug-resistant HL-60/ADR cells. Cancer Res 2004; 64:6271-9. [PMID: 15342415 DOI: 10.1158/0008-5472.can-03-1476] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Treatment with doxorubicin (DOX) induced apoptosis with an increase of ceramide content in drug-sensitive HL-60 cells, but not in drug-resistant HL-60/ADR cells. In HL-60/ADR cells (but not in HL-60 cells), the levels of mRNA, protein, and activity in glucosylceramide synthase (GCS), which converts ceramide to glucosylceramide, were up-regulated in response to DOX. Thus, abrogation of apoptosis in HL-60/ADR cells might be involved in ceramide reduction through DOX-induced up-regulation of GCS function. Because we reported that a GC-rich/Sp1 promoter binding region was of importance in the regulation of GCS expression, the role of Sp1 in DOX-induced up-regulation of GCS and apoptosis was investigated. DOX induced Sp1 activation in HL-60/ADR cells, as assessed by Sp1 gel shift and promoter-luciferase reporter assays, whereas transfection of double-stranded oligodeoxynucleotides (ODNs) containing a GC-rich/Sp1 region (Sp1 decoy ODNs) inhibited DOX-induced Sp1 activation. In addition, DOX-increased mRNA and enzyme activity in GCS were inhibited by Sp1 decoy, in conjunction with corresponding elevations of ceramide content. Moreover, DOX-induced apoptotic cell death was significantly increased in Sp1 decoy ODN-transfected HL-60/ADR cells over mock-transfected HL-60/ADR cells. Together, the results suggest that transcriptional up-regulation of GCS through DOX-induced activation of Sp1 is one potential mechanism to regulate ceramide increase and apoptosis in HL-60/ADR cells.
Collapse
Affiliation(s)
- Yoshikazu Uchida
- Department of Hematology and Oncology, Clinical Sciences for Pathological Organs, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
136
|
Batra S, Reynolds CP, Maurer BJ. Fenretinide Cytotoxicity for Ewing’s Sarcoma and Primitive Neuroectodermal Tumor Cell Lines Is Decreased by Hypoxia and Synergistically Enhanced by Ceramide Modulators. Cancer Res 2004; 64:5415-24. [PMID: 15289350 DOI: 10.1158/0008-5472.can-04-0377] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Patients with disseminated Ewing's family of tumors (ESFT) often experience drug-resistant relapse. We hypothesize that targeting minimal residual disease with the cytotoxic retinoid N-(4-hydroxyphenyl) retinamide (4-HPR; fenretinide) may decrease relapse. We determined the following: (a) 4-HPR cytotoxicity against 12 ESFT cell lines in vitro; (b) whether 4-HPR increased ceramide species (saturated and desaturated ceramides); (c) whether physiological hypoxia (2% O(2)) affected cytotoxicity, mitochondrial membrane potential (DeltaPsi(m)) change, or ceramide species or reactive oxygen species levels; (d) whether cytotoxicity was enhanced by l-threo-dihydrosphingosine (safingol); (e) whether physiological hypoxia increased acid ceramidase (AC) expression; and (f) the effect of the AC inhibitor N-oleoyl-ethanolamine (NOE) on cytotoxicity and ceramide species. Ceramide species were quantified by thin-layer chromatography and scintillography. Cytotoxicity was measured by a fluorescence-based assay using digital imaging microscopy (DIMSCAN). Gene expression profiling was performed by oligonucleotide array analysis. We observed, in 12 cell lines tested in normoxia (20% O(2)), that the mean 4-HPR LC(99) (the drug concentration lethal to 99% of cells) = 6.1 +/- 5.4 microm (range, 1.7-21.8 microm); safingol (1-3 microm) synergistically increased 4-HPR cytotoxicity and reduced the mean 4-HPR LC(99) to 3.2 +/- 1.7 microm (range, 2.0-8.0 microm; combination index < 1). 4-HPR increased ceramide species in the three cell lines tested (up to 9-fold; P < 0.05). Hypoxia (2% O(2)) reduced ceramide species increase, DeltaPsi(m) loss, reactive oxygen species increase (P < 0.05), and 4-HPR cytotoxicity (P = 0.05; 4-HPR LC(99), 19.7 +/- 23.9 microm; range, 2.3-91.4). However, hypoxia affected 4-HPR + safingol cytotoxicity to a lesser extent (P = 0.04; 4-HPR LC(99), 4.9 +/- 2.3 microm; range, 2.0-8.2). Hypoxia increased AC RNA expression; the AC inhibitor NOE enhanced 4-HPR-induced ceramide species increase and cytotoxicity. The antioxidant N-acetyl-l-cysteine somewhat reduced 4-HPR cytotoxicity but did not affect ceramide species increase. We conclude the following: (a) 4-HPR was active against ESFT cell lines in vitro at concentrations achievable clinically, but activity was decreased in hypoxia; and (b) combining 4-HPR with ceramide modulators synergized 4-HPR cytotoxicity in normoxia and hypoxia.
Collapse
Affiliation(s)
- Sandeep Batra
- Division of Hematology-Oncology, Children's Hospital Los Angeles, 4650 Sunset Boulevard, Los Angeles, CA 90027, USA
| | | | | |
Collapse
|
137
|
Norris-Cervetto E, Callaghan R, Platt FM, Dwek RA, Butters TD. Inhibition of glucosylceramide synthase does not reverse drug resistance in cancer cells. J Biol Chem 2004; 279:40412-8. [PMID: 15263008 DOI: 10.1074/jbc.m404466200] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The multidrug-resistant cancer cell lines NCI/AdR(RES) and MES-SA/DX-5 have higher glycolipid levels and higher P-glycoprotein expression than the chemosensitive cell lines MCF7-wt and MES-SA. Inhibiting glycolipid biosynthesis by blocking glucosylceramide synthase has been proposed to reverse drug resistance in MDR cells by causing an increased accumulation of proapoptotic ceramide during treatment of cells with cytotoxic drugs. We treated both multidrug-resistant cell lines with the glucosylceramide synthase inhibitors PDMP (d-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol), C9DGJ (N-nonyl-deoxygalactonojirimycin) or C4DGJ (N-butyl-deoxygalactonojirimycin). PDMP achieved a significant reversal of drug resistance in agreement with previous reports. However, the N-alkylated iminosugars C9DGJ and C4DGJ, which are more selective glucosylceramide synthase inhibitors than PDMP, failed to cause any reversal of drug resistance despite depleting glycolipids to the same extent as PDMP. Our results suggest that (a) inhibition of glucosylceramide synthase does not reverse multidrug resistance and (b) the chemosensitization achieved by PDMP cannot be caused by inhibition of glucosylceramide synthase alone.
Collapse
MESH Headings
- 1-Deoxynojirimycin/analogs & derivatives
- ATP Binding Cassette Transporter, Subfamily B/metabolism
- ATP Binding Cassette Transporter, Subfamily B, Member 1/antagonists & inhibitors
- Antineoplastic Agents, Phytogenic/pharmacology
- Cell Line, Tumor
- Ceramides/metabolism
- Chromatography, High Pressure Liquid
- Chromatography, Thin Layer
- Dose-Response Relationship, Drug
- Drug Resistance, Multiple
- Drug Resistance, Neoplasm
- Enzyme Inhibitors/pharmacology
- Flow Cytometry
- Glucosamine/analogs & derivatives
- Glucosamine/pharmacology
- Glucosylceramides/chemistry
- Glucosyltransferases/antagonists & inhibitors
- Glucosyltransferases/chemistry
- Glycolipids/chemistry
- Glycolipids/metabolism
- Humans
- Imino Sugars
- Lipids/chemistry
- Morpholines/pharmacology
- Quinolines/pharmacology
- Time Factors
- Vinblastine/pharmacology
Collapse
Affiliation(s)
- Edward Norris-Cervetto
- Oxford Glycobiology Institute, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | | | | | | | | |
Collapse
|
138
|
Smoleńska-Sym G, Spychalska J, Zdebska E, Woźniak J, Traczyk Z, Pszenna E, Maj S, Danikiewicz W, Bieńkowski T, Kościelak J. Ceramides and glycosphingolipids in maturation process: leukemic cells as an experimental model. Blood Cells Mol Dis 2004; 33:68-76. [PMID: 15223014 DOI: 10.1016/j.bcmd.2004.04.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2004] [Indexed: 11/25/2022]
Abstract
Leukemic cells were used as experimental material to demonstrate changes in the content of GSLs during the development and maturation of neutrophils. The most abundant cellular GSL is LacCer. An elevation in the LacCer level occurs twice during the maturation process: initially, on formation of azurophil granules, and subsequently, (a more significant rise) on formation of specific granules. The formation of the latter is accompanied by an increase in the level of GalGalCer. During the maturation of myeloblasts, there is a simultaneous growth in the content of LacCer and GM3 as well as that of their common precursors, that is, free ceramides. Like other tumor cells, GM3 rich myeloblasts in the peripheral blood from patients with AML are characterized by shedding of gangliosides. The quantitative Cer/GlcCer ratio in these cells seems to be advantageous for the efficacy of chemotherapy in the induction of apoptosis. Myelo- and metamyelocytes achieve the highest level of GSLs. Their entry into the full maturity stage is accompanied by a decrease in the level of GSLs. Patterns of GSLs expression change greatly during development and maturation. However, with respect to the composition and content of GSLs, there are no significant differences between normal and leukemic mature neutrophils. At each stage of the development and maturation of myelogenous leukemic cells, as well as in normal mature neutrophils, there occurs the synthesis of the same molecular species both free ceramides and ceramide portions of LacCer, precursor of more complex GSLs.
Collapse
Affiliation(s)
- Gabriela Smoleńska-Sym
- Department of Biochemistry, Institute of Hematology and Blood Transfusion Warsaw, Poland.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
139
|
Kohyama-Koganeya A, Sasamura T, Oshima E, Suzuki E, Nishihara S, Ueda R, Hirabayashi Y. Drosophila glucosylceramide synthase: a negative regulator of cell death mediated by proapoptotic factors. J Biol Chem 2004; 279:35995-6002. [PMID: 15210713 DOI: 10.1074/jbc.m400444200] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Glucosylceramide synthase (GlcT-1) catalyzes the formation of glucosylceramide (GlcCer), the core structure of major glycosphingolipids (GSLs), from ceramide and UDP-glucose. Ceramide and its metabolites, such as sphingosine-1-phosphate, are now known to be important mediators of apoptosis and cell survival. Recently, we have shown that GlcT-1 functions to regulate intracellular ceramide levels via glycosylation of ceramide. In this study, we employ the fruit fly Drosophila melanogaster as a model system for understanding the in vivo roles of GlcT-1. We isolated and characterized a GlcT-1 homologue (DGlcT-1) from Drosophila. When DGlcT-1 was expressed in GM-95 cells deficient in GSLs (because of the absence of GlcT-1 activity), these cells regained the ability to synthesize GSLs. Northern blot and in situ hybridization analyses revealed that the expression of DGlcT-1 mRNA was ubiquitous throughout development, suggesting that DGlcT-1 is important for development and differentiation. Indeed, RNA interference experiments demonstrated that the loss of GlcT-1 function enhances apoptotic cell death. Conversely, targeted expression of GlcT-1 partially rescued cell death caused by the proapoptotic factors Reaper and Grim, suggesting that ceramide generation might be one signal pathway that executes the cell death program. We also found that GlcT-1 localized not only in the Golgi apparatus but also in the perinuclear endoplasmic reticulum, providing the first visual evidence of GlcT-1 in membranes. These results indicate that GlcT-1 might down-regulate ceramide generated in these membranes.
Collapse
Affiliation(s)
- Ayako Kohyama-Koganeya
- Neuronal Circuit Mechanisms Research Group, Brain Science Institute, The Institute of Physical and Chemical Research (RIKEN), Wako-shi, Saitama 351-0198, Japan
| | | | | | | | | | | | | |
Collapse
|
140
|
Gouazé V, Yu JY, Bleicher RJ, Han TY, Liu YY, Wang H, Gottesman MM, Bitterman A, Giuliano AE, Cabot MC. Overexpression of glucosylceramide synthase and P-glycoprotein in cancer cells selected for resistance to natural product chemotherapy. Mol Cancer Ther 2004. [DOI: 10.1158/1535-7163.633.3.5] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Resistance to natural product chemotherapy drugs is a major obstacle to successful cancer treatment. This type of resistance is often acquired in response to drug exposure; however, the mechanisms of this adverse reaction are complex and elusive. Here, we have studied acquired resistance to Adriamycin, Vinca alkaloids, and etoposide in MCF-7 breast cancer cells, KB-3-1 epidermoid carcinoma cells, and other cancer cell lines to determine if there is an association between expression of glucosylceramide synthase, the enzyme catalyzing ceramide glycosylation to glucosylceramide, and the multidrug-resistant (MDR) phenotype. This work shows that glucosylceramide levels increase concomitantly with increased drug resistance in the KB-3-1 vinblastine-resistant sublines KB-V.01, KB-V.1, and KB-V1 (listed in order of increasing MDR). The levels of glucosylceramide synthase mRNA, glucosylceramide synthase protein, and P-glycoprotein (P-gp) also increased in parallel. Increased glucosylceramide levels were also present in Adriamycin-resistant KB-3-1 sublines KB-A.05 and KB-A1. In breast cancer, detailed analysis of MCF-7 wild-type and MCF-7-AdrR cells (Adriamycin-resistant) demonstrated enhanced glucosylceramide synthase message and protein, P-gp message and protein, and high levels of glucosylceramide in resistant cells. Similar results were seen in vincristine-resistant leukemia, etoposide-resistant melanoma, and Adriamycin-resistant colon cancer cell lines. Cell-free glucosylceramide synthase activity was higher in lysates obtained from drug-resistant cells. Lastly, glucosylceramide synthase promoter activity was 15-fold higher in MCF-7-AdrR compared with MCF-7 cells. We conclude that selection pressure for resistance to natural product chemotherapy drugs selects for enhanced ceramide metabolism through glucosylceramide synthase in addition to enhanced P-gp expression. A possible connection between glucosylceramide synthase and P-gp in drug resistance biology is suggested.
Collapse
Affiliation(s)
- Valerie Gouazé
- 1John Wayne Cancer Institute at Saint John's Health Center, Santa Monica, California
| | - Jing Y. Yu
- 1John Wayne Cancer Institute at Saint John's Health Center, Santa Monica, California
| | | | - Tie-Yan Han
- 1John Wayne Cancer Institute at Saint John's Health Center, Santa Monica, California
| | - Yong-Yu Liu
- 1John Wayne Cancer Institute at Saint John's Health Center, Santa Monica, California
| | - Hongtao Wang
- 1John Wayne Cancer Institute at Saint John's Health Center, Santa Monica, California
| | | | - Arie Bitterman
- 3Department of Surgery A, Carmel Medical Center, Haifa, Israel; and
| | - Armando E. Giuliano
- 1John Wayne Cancer Institute at Saint John's Health Center, Santa Monica, California
| | - Myles C. Cabot
- 1John Wayne Cancer Institute at Saint John's Health Center, Santa Monica, California
| |
Collapse
|
141
|
Liu YY, Han TY, Yu JY, Bitterman A, Le A, Giuliano AE, Cabot MC. Oligonucleotides blocking glucosylceramide synthase expression selectively reverse drug resistance in cancer cells. J Lipid Res 2004; 45:933-40. [PMID: 14967819 DOI: 10.1194/jlr.m300486-jlr200] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
High glucosylceramide synthase (GCS) activity is one factor contributing to multidrug resistance (MDR) in breast cancer. Enforced GCS overexpression has been shown to disrupt ceramide-induced apoptosis and to confer resistance to doxorubicin. To examine whether GCS is a target for cancer therapy, we have designed and tested the effects of antisense oligodeoxyribonucleotides (ODNs) to GCS on gene expression and chemosensitivity in multidrug-resistant cancer cells. Here, we demonstrate that antisense GCS (asGCS) ODN-7 blocked cellular GCS expression and selectively increased the cytotoxicity of anticancer agents. Pretreatment with asGCS ODN-7 increased doxorubicin sensitivity by 17-fold in MCF-7-AdrR (doxorubicin-resistant) breast cancer cells and by 10-fold in A2780-AD (doxorubicin-resistant) ovarian cancer cells. In MCF-7 drug-sensitive breast cancer cells, asGCS ODN-7 only increased doxorubicin sensitivity by 3-fold, and it did not influence doxorubicin cytotoxicity in normal human mammary epithelial cells. asGCS ODN-7 was shown to be more efficient in reversing drug resistance than either the GCS chemical inhibitor d-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol or the P-glycoprotein blocking agents verapamil and cyclosporin A. Experiments defining drug transport and lipid metabolism parameters showed that asGCS ODN-7 overcomes drug resistance mainly by enhancing drug uptake and ceramide-induced apoptosis. This study demonstrates that a 20-mer asGCS oligonucleotide effectively reverses MDR in human cancer cells.
Collapse
Affiliation(s)
- Yong-Yu Liu
- John Wayne Cancer Institute at Saint John's Health Center, Santa Monica, CA, USA.
| | | | | | | | | | | | | |
Collapse
|
142
|
Grazide S, Terrisse AD, Lerouge S, Laurent G, Jaffrézou JP. Cytoprotective effect of glucosylceramide synthase inhibition against daunorubicin-induced apoptosis in human leukemic cell lines. J Biol Chem 2004; 279:18256-61. [PMID: 14766899 DOI: 10.1074/jbc.m314105200] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Several studies have shown that ceramide (CER) glucosylation contributes to drug resistance in multidrug-resistant cells and that inhibition of glucosylceramide synthase sensitizes cells to various drug treatments. However, the role of glucosylceramide synthase has not been studied in drug-sensitive cancer cells. We have demonstrated previously that the anthracycline daunorubicin (DNR) rapidly induces interphasic apoptosis through neutral sphingomyelinase-mediated CER generation in human leukemic cell lines. We now report that inhibition of glucosylceramide synthase using d,l-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP) or 1-phenyl-2-palmitoylamino-3-morpholino-1-propanol (PPMP) protected U937 and HL-60 cells from DNR-induced apoptosis. Moreover, blocking CER glucosylation did not lead to increased CER levels but to increased CER galactosylation. We also observed that pretreating cells with galactosylceramide (GalCER) significantly inhibited DNR-induced apoptosis. Finally, we show that GalCER-enriched lymphoblast cells (Krabbe's disease) were significantly more resistant to DNR- and cytosine arabinoside-induced apoptosis as compared with normal lymphoblasts, whereas glucosylceramide-enriched cells (Gaucher's disease) were more sensitive. In conclusion, this study suggests that sphingomyelin-derived CER in itself is not a second messenger but rather a precursor of both an apoptosis second messenger (GD3) and an apoptosis "protector" (GalCER).
Collapse
Affiliation(s)
- Solène Grazide
- INSERM U563-Centre de Physiopathologie Toulouse Purpan, Institut Claudius Régaud, Toulouse 31052, France
| | | | | | | | | |
Collapse
|
143
|
Morris R, Cox H, Mombelli E, Quinn PJ. Rafts, little caves and large potholes: how lipid structure interacts with membrane proteins to create functionally diverse membrane environments. Subcell Biochem 2004; 37:35-118. [PMID: 15376618 DOI: 10.1007/978-1-4757-5806-1_2] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
This chapter reviews how diverse lipid microdomains form in the membrane and partition proteins into different functional units that regulate cell trafficking, signalling and movement. We will concentrate upon five major issues: 1. the diversity of lipid structure that produces diverse microenvironments into which different subsets of proteins partition; 2. why ordered lipid domains exclude proteins, and the conditions required for select subsets of proteins to enter these domains; 3. the coupling of the inner and outer leaflets within ordered microdomains; 4. the effect of ordered lipid domains upon membrane properties including curvature and hydrophobicity that affect membrane fission, fusion and extension of filopodia; 5. the biological effects of these structural constraints; in particular how the properties of these domains combine to provide a very different signalling, trafficking and membrane fusion environment to that found in disordered (fluid mosaic) membrane. In addressing these problems, the review draws upon studies ranging from molecular dynamic modelling of lipid interactions, through physical studies of model membrane systems to structural and biological studies of whole cells, examining in the process problems inherent in visualising and purifying these microdomains. While the diversity of structure and function of ordered lipid microdomains is emphasised, some general roles emerge. In particular, the basis for having quite different, non-interacting ordered lipid domains on the same membrane is evident in the diversity of lipid structure and plays a key role in sorting signalling systems. The exclusion of ordered membrane from coated pits, and hence rapid endocytosis, is suggested to underlie the ability of highly ordered domains to establish stable secondary signalling systems required, for instance, in T cell receptor, insulin and neurotrophin signalling.
Collapse
Affiliation(s)
- Roger Morris
- Molecular Neurobiology Group, MRC Centre for Developmental Neurobiology, King's College, London, UK
| | | | | | | |
Collapse
|
144
|
De Rosa MF, Sillence D, Ackerley C, Lingwood C. Role of multiple drug resistance protein 1 in neutral but not acidic glycosphingolipid biosynthesis. J Biol Chem 2003; 279:7867-76. [PMID: 14662772 DOI: 10.1074/jbc.m305645200] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Transfection studies have implicated the multiple drug resistance pump, MDR1, as a glucosyl ceramide translocase within the Golgi complex (Lala, P., Ito, S., and Lingwood, C. A. (2000) J. Biol. Chem. 275, 6246-6251). We now show that MDR1 inhibitors, cyclosporin A or ketoconazole, inhibit neutral glycosphingolipid biosynthesis in 11 of 12 cell lines tested. The exception, HeLa cells, do not express MDR1. Microsomal lactosyl ceramide and globotriaosyl ceramide synthesis from endogenous or exogenously added liposomal glucosyl ceramide was inhibited by cyclosporin A, consistent with a direct role for MDR1/glucosyl ceramide translocase activity in their synthesis. In contrast, cellular ganglioside synthesis in the same cells, was unaffected by MDR1 inhibition, suggesting neutral and acid glycosphingolipids are synthesized from distinct precursor glycosphingolipid pools. Metabolic labeling in wild type and knock-out (MDR1a, 1b, MRP1) mouse fibroblasts showed the same loss of neutral glycosphingolipid (glucosyl ceramide, lactosyl ceramide) but not ganglioside (GM3) synthesis, confirming the proposed role for MDR1 translocase activity. Cryo-immunoelectron microscopy showed MDR1 was predominantly intracellular, largely in rab6-containing Golgi vesicles and Golgi cisternae, the site of glycosphingolipid synthesis. These studies identify MDR1 as the major glucosyl ceramide flippase required for neutral glycosphingolipid anabolism and demonstrate a previously unappreciated dichotomy between neutral and acid glycosphingolipid synthesis.
Collapse
Affiliation(s)
- María Fabiana De Rosa
- Research Institute and Department of Pediatric Laboratory Medicine, Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada
| | | | | | | |
Collapse
|
145
|
Dagan A, Wang C, Fibach E, Gatt S. Synthetic, non-natural sphingolipid analogs inhibit the biosynthesis of cellular sphingolipids, elevate ceramide and induce apoptotic cell death. Biochim Biophys Acta Mol Cell Biol Lipids 2003; 1633:161-9. [PMID: 14499735 DOI: 10.1016/s1388-1981(03)00122-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Numerous studies have demonstrated the participation of sphingolipids in signal transduction and regulation of cell growth. Several cellular stress agents have been shown to elevate ceramide, the basic precursor of all sphingolipids, initiating a cascade of events leading to arrest of the cell cycle, apoptosis and cell death. Aiming at inhibiting metabolic pathways of sphingolipid metabolism that might lead to an increase of cellular ceramide, we have synthesized non-natural analogs of ceramide, sphingosine and trimethylsphingosine. When the respective analogs were applied to HL60 human myeloid leukemic cells they inhibited the biosynthesis of sphingomyelin (SPM) and glycosphingolipids and induced apoptosis that led to cell death. A fluorescent procedure which has been developed for quantifying the biosynthesis of cellular ceramide indicated an increase in the ceramide content following an incubation with the synthetic analogs. These results suggest that the newly synthesized sphingolipid analogs might be valuable for potential application as a therapeutic modality in leukemia and other malignancies.
Collapse
Affiliation(s)
- Arie Dagan
- Department of Biochemistry, Hebrew University-Hadassah School of Medicine, Jerusalem, Israel.
| | | | | | | |
Collapse
|
146
|
Mohan RR, Possin DE, Mohan RR, Sinha S, Wilson SE. Development of genetically engineered tet HPV16-E6/E7 transduced human corneal epithelial clones having tight regulation of proliferation and normal differentiation. Exp Eye Res 2003; 77:395-407. [PMID: 12957140 DOI: 10.1016/s0014-4835(03)00175-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Lack of an optimal in vitro model of human corneal epithelial (HCE) cells is a major limitation in studying normal functions and gene regulations in HCE. Moreover, availability of a multi-layered HCE culture can reduce the usage of animals in the toxicity testing of consumer products. We have developed tetracycline-responsive human papilloma virus (HPV) 16-E6/E7 transduced HCE clones showing tight regulation of proliferation and normal differentiation. Expression of HPV16-E6/E7 mRNA and HPV16-E7 and keratin K3 proteins was examined by RNase protection assay and western blotting, respectively, in presence and absence (+/-) of Dox in identified clones. Localization of cornea-specific keratin k3 in +/- of Dox was evaluated by immunocytochemistry. The response of growth factors such as hepatocyte growth factor (HGF) and epidermal growth factor to the cellular proliferation in +/- of Dox in the newly identified clones was measured by cell counting. Cellular morphology, formation of multi-layered cultures at air-liquid interface and ultrastructural features were evaluated by light and transmission electron microscopy. The physical barrier established by the newly developed clones was determined by the transepithelial permeability to sodium fluorescein and transepithelial electrical resistance assays in the airlifted-stratified cultures.
Collapse
Affiliation(s)
- Rajiv R Mohan
- Department of Ophthalmology, School of Medicine, University of Washington, Seattle 98195 6485, USA.
| | | | | | | | | |
Collapse
|
147
|
Dijkhuis AJ, Douwes J, Kamps W, Sietsma H, Kok JW. Differential expression of sphingolipids in P-glycoprotein or multidrug resistance-related protein 1 expressing human neuroblastoma cell lines. FEBS Lett 2003; 548:28-32. [PMID: 12885402 DOI: 10.1016/s0014-5793(03)00721-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The sphingolipid composition and multidrug resistance status of three human neuroblastoma cell lines were established. SK-N-FI cells displayed high expression and functional (efflux) activity of P-glycoprotein, while multidrug resistance-related protein 1 was relatively abundant and most active in SK-N-AS cells. These two cell lines exhibited higher sphingolipid levels, compared to SK-N-DZ, which had the lowest activity of either ATP-binding cassette transporter protein. SK-N-DZ cells also differed in ganglioside composition with predominant expression of b-series gangliosides. In conclusion, these three neuroblastoma cell lines offer a good model system to study sphingolipid metabolism in relation to ATP-binding cassette transporter protein function.
Collapse
Affiliation(s)
- Anne-Jan Dijkhuis
- Department of Membrane Cell Biology, Groningen University Institute for Drug Exploration (GUIDE), University of Groningen, A. Deusinglaan 1, Bldg. 3215, 10th Fl., 9713 AV, Groningen, The Netherlands.
| | | | | | | | | |
Collapse
|
148
|
Affiliation(s)
- David K Perry
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC 29425, USA
| | | |
Collapse
|
149
|
Ermak G, Cancasci VJ, Davies KJA. Cytotoxic effect of doxycycline and its implications for tet-on gene expression systems. Anal Biochem 2003; 318:152-4. [PMID: 12782044 DOI: 10.1016/s0003-2697(03)00166-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Gennady Ermak
- Ethel Percy Andrus Gerontology Center, The University of Southern California, Los Angeles, CA 90089-0191, USA.
| | | | | |
Collapse
|
150
|
Veldman RJ, Mita A, Cuvillier O, Garcia V, Klappe K, Medin JA, Campbell JD, Carpentier S, Kok JW, Levade T. The absence of functional glucosylceramide synthase does not sensitize melanoma cells for anticancer drugs. FASEB J 2003; 17:1144-6. [PMID: 12692077 DOI: 10.1096/fj.02-1053fje] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Conversion of ceramide, a putative mediator of anticancer drug-induced apoptosis, into glucosylceramide, by the action of glucosylceramide synthase (GCS), has been implicated in drug resistance. Herein, we compared GM95 mouse melanoma cells deficient in GCS activity, with cells stably transfected with a vector encoding GCS (GM95/GCS). Enzymatic and metabolic analysis demonstrated that GM95/GCS cells expressed a fully functional enzyme, resulting in normal ceramide glycosylation. However, cytotoxicity assays, as well as caspase activation and cytochrome c release studies, did not reveal any difference between the two cell lines with respect to their sensitivity toward doxorubicin, vinblastine, paclitaxel, cytosine arabinoside, or short-chain ceramide analogs. Administration of doxorubicin resulted in ceramide accumulation in both cell lines, with similar kinetics and amplitude. Although glucosylceramide formation was detected in doxorubicin-treated GM95/GCS cells, metabolism of drug-induced ceramide did not appear to be instrumental in cell survival. Furthermore, N-(n-butyl)deoxynojirimycin, a potent and non-toxic GCS inhibitor, had no chemosensitizing effect on wild-type melanoma cells. Altogether, both genetic and pharmacological alterations of the cellular ceramide glycosylation capacity failed to sensitize melanoma cells to anticancer drugs, therefore moderating the importance of ceramide glucosylation in drug-resistance mechanisms.
Collapse
Affiliation(s)
- Robert Jan Veldman
- INSERM U.466, Laboratoire de Biochimie, Institut Louis Bugnard, CHU Rangueil, 1 avenue Jean Poulhès, TSA 50032, 31059 Toulouse Cedex 9, France
| | | | | | | | | | | | | | | | | | | |
Collapse
|