151
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Hornick JR, Vangveravong S, Spitzer D, Abate C, Berardi F, Goedegebuure P, Mach RH, Hawkins WG. Lysosomal membrane permeabilization is an early event in Sigma-2 receptor ligand mediated cell death in pancreatic cancer. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2012; 31:41. [PMID: 22551149 PMCID: PMC3414770 DOI: 10.1186/1756-9966-31-41] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/01/2012] [Accepted: 05/02/2012] [Indexed: 01/13/2023]
Abstract
Background Sigma-2 receptor ligands have been studied for treatment of pancreatic cancer because they are preferentially internalized by proliferating cells and induce apoptosis. This mechanism of apoptosis is poorly understood, with varying reports of caspase-3 dependence. We evaluated multiple sigma-2 receptor ligands in this study, each shown to decrease tumor burden in preclinical models of human pancreatic cancer. Results Fluorescently labeled sigma-2 receptor ligands of two classes (derivatives of SW43 and PB282) localize to cell membrane components in Bxpc3 and Aspc1 pancreatic cancer cells and accumulate in lysosomes. We found that interactions in the lysosome are critical for cell death following sigma-2 ligand treatment because selective inhibition of a protective lysosomal membrane glycoprotein, LAMP1, with shRNA greatly reduced the viability of cells following treatment. Sigma-2 ligands induced lysosomal membrane permeabilization (LMP) and protease translocation triggering downstream effectors of apoptosis. Subsequently, cellular oxidative stress was greatly increased following treatment with SW43, and the hydrophilic antioxidant N-acetylcysteine (NAC) gave greater protection against this than a lipophilic antioxidant, α-tocopherol (α-toco). Conversely, PB282-mediated cytotoxicity relied less on cellular oxidation, even though α-toco did provide protection from this ligand. In addition, we found that caspase-3 induction was not as significantly inhibited by cathepsin inhibitors as by antioxidants. Both NAC and α-toco protected against caspase-3 induction following PB282 treatment, while only NAC offered protection following SW43 treatment. The caspase-3 inhibitor DEVD-FMK offered significant protection from PB282, but not SW43. Conclusions Sigma-2 ligand SW43 commits pancreatic cancer cells to death by a caspase-independent process involving LMP and oxidative stress which is protected from by NAC. PB282 however undergoes a caspase-dependent death following LMP protected by DEVD-FMK and α-toco, which is also known to stabilize the mitochondrial membrane during apoptotic stimuli. These differences in mechanism are likely dependent on the structural class of the compounds versus the inherent sigma-2 binding affinity. As resistance of pancreatic cancers to specific apoptotic stimuli from chemotherapy is better appreciated, and patient-tailored treatments become more available, ligands with high sigma-2 receptor affinity should be chosen based on sensitivities to apoptotic pathways.
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Affiliation(s)
- John R Hornick
- Department of Surgery, Washington University School of Medicine, S, Euclid Avenue, St, Louis, MO, USA
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152
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Transient elevation of serum cystatin C concentrations during perioperative cisplatin-based chemotherapy in esophageal cancer patients. Cancer Chemother Pharmacol 2012; 69:1537-44. [DOI: 10.1007/s00280-012-1860-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Accepted: 03/05/2012] [Indexed: 10/28/2022]
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153
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Nyman U, Muppani NR, Zhivotovsky B, Joseph B. Hsp72 mediates TAp73α anti-apoptotic effects in small cell lung carcinoma cells. J Cell Mol Med 2012; 15:1757-68. [PMID: 20807285 PMCID: PMC4373366 DOI: 10.1111/j.1582-4934.2010.01166.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The transcription factor p73, a member of the p53 family of proteins, is involved in the regulation of cell cycle progression and apoptosis. Due to alternative promoters and carboxy-terminal splicing, the P73 gene gives rise to a range of different isoforms. Interestingly, a particular increase in expression of the TAp73α isoform has been reported in various tumours. In addition, TAp73α has been shown to inhibit Bax activation and mitochondrial dysfunctions and thereby to confer small cell lung carcinoma (SCLC) cells resistance to drug-induced apoptosis. However, the precise mechanism by which TAp73α exerts its pro-survival effect is yet unclear. Here we report that TAp73α, but not TAp73β, regulates the expression of inducible Hsp72/HSPA1A. Hsp72 proved to be required for the survival effects of TAp73α as antisense knockdown of Hsp72 resulted in an abolishment of the anti-apoptotic effect of TAp73α in SCLC cells upon Etoposide treatment. Importantly, depletion of Hsp72 allowed activation of Bax, loss of mitochondrial membrane potential and lysosomal membrane permeabilization in SCLC cells even in the presence of TAp73α. Finally, we revealed that TAp73β counteracts the anti-apoptotic effect of TAp73α by preventing Hsp72 induction. Our results thus provide additional evidence for the potential oncogenic role of TAp73α, and extend the understanding of the mechanism for its anti-apoptotic effect.
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Affiliation(s)
- Ulrika Nyman
- Department of Oncology-Pathology, Cancer Centrum Karolinska, Karolinska Institutet, Stockholm, Sweden
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154
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Moles A, Tarrats N, Fernández-Checa JC, Marí M. Cathepsin B overexpression due to acid sphingomyelinase ablation promotes liver fibrosis in Niemann-Pick disease. J Biol Chem 2011; 287:1178-88. [PMID: 22102288 DOI: 10.1074/jbc.m111.272393] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Niemann-Pick disease (NPD) is a lysosomal storage disease caused by the loss of acid sphingomyelinase (ASMase) that features neurodegeneration and liver disease. Because ASMase-knock-out mice models NPD and our previous findings revealed that ASMase activates cathepsins B/D (CtsB/D), our aim was to investigate the expression and processing of CtsB/D in hepatic stellate cells (HSCs) from ASMase-null mice and their role in liver fibrosis. Surprisingly, HSCs from ASMase-knock-out mice exhibit increased basal level and activity of CtsB as well as its in vitro processing in culture, paralleling the enhanced expression of fibrogenic markers α-smooth muscle actin (α-SMA), TGF-β, and pro-collagen-α1(I) (Col1A1). Moreover, pharmacological inhibition of CtsB blunted the expression of α-SMA and Col1A1 and proliferation of HSCs from ASMase-knock-out mice. Consistent with the enhanced activation of CtsB in HSCs from ASMase-null mice, the in vivo liver fibrosis induced by chronic treatment with CCl(4) increased in ASMase-null compared with wild-type mice, an effect that was reduced upon CtsB inhibition. In addition to liver, the enhanced proteolytic processing of CtsB was also observed in brain and lung of ASMase-knock-out mice, suggesting that the overexpression of CtsB may underlie the phenotype of NPD. Thus, these findings reveal a functional relationship between ASMase and CtsB and that the ablation of ASMase leads to the enhanced processing and activation of CtsB. Therefore, targeting CtsB may be of relevance in the treatment of liver fibrosis in patients with NPD.
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Affiliation(s)
- Anna Moles
- Liver Unit-Hospital Clínic, Centro de Investigación Biomédica en Red en el Área Temática de Entermedades Hepáticas y Digestivas, and Department of Cell Death and Proliferation, Instituto de Investigaciones Biomédicas de Barcelona, Consejo Superior de Investigaciones Científicas, 08036 Barcelona, Spain
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155
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Repnik U, Stoka V, Turk V, Turk B. Lysosomes and lysosomal cathepsins in cell death. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2011; 1824:22-33. [PMID: 21914490 DOI: 10.1016/j.bbapap.2011.08.016] [Citation(s) in RCA: 292] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Revised: 08/24/2011] [Accepted: 08/26/2011] [Indexed: 12/30/2022]
Abstract
Lysosomes are the key degradative compartments of the cell. Lysosomal cathepsins, which are enclosed in the lysosomes, help to maintain the homeostasis of the cell's metabolism by participating in the degradation of heterophagic and autophagic material. Following the targeted lysosomal membrane's destabilization, the cathepsins can be released into the cytosol and initiate the lysosomal pathway of apoptosis through the cleavage of Bid and the degradation of the anti-apoptotic Bcl-2 homologues. Cathepsins can also amplify the apoptotic signaling, when the lysosomal membranes are destabilized at a later stage of apoptosis, initiated by other stimuli. However, the functional integrity of the lysosomal compartment during apoptosis enables efficient autophagy, which can counteract apoptosis by providing the energy source and by disposing the damaged mitochondria, which generate the ROS. Impairing autophagy by disabling the lysosome function is being investigated as an adjuvant therapeutic approach to sensitize cells to apoptosis-inducing agents. Destabilization of the lysosomal membranes by the lysosomotropic detergents seems to be a promising strategy in this context as it would not only disable autophagy, but also promote apoptosis through the initiation of the lysosomal pathway. In contrast, the impaired autophagy and lysosomal degradation linked with the increased oxidative stress underlie degenerative changes in the aging neurons. This further suggests that lysosomes and lysosomal cathepsins have a dual role in cell death. This article is part of a Special Issue entitled: Proteolysis 50 years after the discovery of lysosome.
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Affiliation(s)
- Urška Repnik
- Department of Biochemistry and Molecular and Structural Biology, J. Stefan Institute, Jamova, Ljubljana, Slovenia
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156
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SerpinB3, a new prognostic tool in breast cancer patients treated with neoadjuvant chemotherapy. Breast Cancer Res Treat 2011; 132:807-18. [PMID: 21695460 DOI: 10.1007/s10549-011-1625-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2011] [Accepted: 06/02/2011] [Indexed: 10/18/2022]
Abstract
It is unclear which patients with breast cancer benefit from anthracycline-based neoadjuvant chemotherapy and whether taxanes increase survival. Hsp70 and serpinB3 inhibit a lysosomal cell death pathway induced in anthracycline and taxane treated cells, which may be critical for breast cancer cell survival. Thus we evaluated serpinB3 and Hsp70 as putative prognostic biomarkers in breast cancer patients treated with neoadjuvant chemotherapy. SerpinB3 and Hsp70 were measured by immunohistochemistry in residual breast tumours of patients without a complete pathological response [pCR] (n = 250), from a retrospective cohort of 296 patients treated with anthracycline-based chemotherapy with or without sequential docetaxel prior to surgical resection. SerpinB3 (P = 0.02) and Hsp70 (P = 0.008) positivity in residual tumour were associated with a poor pathological response and serpinB3 was an independent prognostic biomarker (HR 2.1 (95% CI 1.2-3.8), P = 0.02). Docetaxel significantly improved overall survival of breast cancer patients treated with neoadjuvant chemotherapy. Furthermore, serpinB3 positivity predicted poor survival in patients treated with anthracycline-based chemotherapy alone (P = 0.02), but those with serpinB3 negative tumours had as equally good survival as those also treated with docetaxel (P = 0.7). Survival was independent of serpinB3 expression in patients who received sequential docetaxel. The Nottingham prognostic index (NPI), calculated at surgical resection, predicted overall survival in these neoadjuvantly treated patients (P < 0.001) and serpinB3 status segregated patients with a moderate NPI into distinct prognostic subgroups. The use of clinical (NPI) and molecular (serpinB3) biomarkers measured at surgical resection to provide accurate prognostication in patients who do not achieve a pCR following neoadjuvant chemotherapy could facilitate optimal post-operative clinical management of these patients and is of significant clinical value. Furthermore, serpinB3 status in residual tumour is a biomarker of neoadjuvant docetaxel benefit in patients not achieving a pCR and use of serpinB3 molecular subtyping for adjuvant docetaxel treatment planning warrants further investigation.
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157
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Nylandsted J, Becker AC, Bunkenborg J, Andersen JS, Dengjel J, Jäättelä M. ErbB2-associated changes in the lysosomal proteome. Proteomics 2011; 11:2830-8. [DOI: 10.1002/pmic.201000734] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2010] [Revised: 04/01/2011] [Accepted: 04/20/2011] [Indexed: 01/01/2023]
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158
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Appelqvist H, Nilsson C, Garner B, Brown AJ, Kågedal K, Ollinger K. Attenuation of the lysosomal death pathway by lysosomal cholesterol accumulation. THE AMERICAN JOURNAL OF PATHOLOGY 2011; 178:629-39. [PMID: 21281795 DOI: 10.1016/j.ajpath.2010.10.030] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Revised: 09/24/2010] [Accepted: 10/21/2010] [Indexed: 10/18/2022]
Abstract
In the past decade, lysosomal membrane permeabilization (LMP) has emerged as a significant component of cell death signaling. The mechanisms by which lysosomal stability is regulated are not yet fully understood, but changes in the lysosomal membrane lipid composition have been suggested to be involved. Our aim was to investigate the importance of cholesterol in the regulation of lysosomal membrane permeability and its potential impact on apoptosis. Treatment of normal human fibroblasts with U18666A, an amphiphilic drug that inhibits cholesterol transport and causes accumulation of cholesterol in lysosomes, rescued cells from lysosome-dependent cell death induced by the lysosomotropic detergent O-methyl-serine dodecylamide hydrochloride (MSDH), staurosporine (STS), or cisplatin. LMP was decreased by pretreating cells with U18666A, and there was a linear relationship between the cholesterol content of lysosomes and their resistance to permeabilization induced by MSDH. U18666A did not induce changes in expression or localization of 70-kDa heat shock proteins (Hsp70) or antiapoptotic Bcl-2 proteins known to protect the lysosomal membrane. Induction of autophagy also was excluded as a contributor to the protective mechanism. By using Chinese hamster ovary (CHO) cells with lysosomal cholesterol overload due to a mutation in the cholesterol transporting protein Niemann-Pick type C1 (NPC1), the relationship between lysosomal cholesterol accumulation and protection from lysosome-dependent cell death was confirmed. Cholesterol accumulation in lysosomes attenuates apoptosis by increasing lysosomal membrane stability.
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Affiliation(s)
- Hanna Appelqvist
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden.
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159
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Luke CJ, Silverman GA. Necrotic cell death: harnessing the Dark side of the Force in mammary gland involution. Nat Cell Biol 2011; 13:197-9. [PMID: 21364568 DOI: 10.1038/ncb0311-197] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
In response to major cellular insults, a massive increase in lysosomal membrane permeability (LMP) leads to necrosis. Data now reveal that this potent lysosomal-mediated necrotic cell-death machinery can also be harnessed for complex physiological processes, such as post-lactation mammary gland involution.
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160
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Stat3 controls lysosomal-mediated cell death in vivo. Nat Cell Biol 2011; 13:303-9. [PMID: 21336304 DOI: 10.1038/ncb2171] [Citation(s) in RCA: 236] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2010] [Accepted: 12/15/2010] [Indexed: 01/05/2023]
Abstract
It is well established that lysosomes play an active role during the execution of cell death. A range of stimuli can lead to lysosomal membrane permeabilization (LMP), thus inducing programmed cell death without involvement of the classical apoptotic programme. However, these lysosomal pathways of cell death have mostly been described in vitro or under pathological conditions. Here we show that the physiological process of post-lactational regression of the mammary gland is accomplished through a non-classical, lysosomal-mediated pathway of cell death. We found that, during involution, lysosomes in the mammary epithelium undergo widespread LMP. Furthermore, although cell death through LMP is independent of executioner caspases 3, 6 and 7, it requires Stat3, which upregulates the expression of lysosomal proteases cathepsin B and L, while downregulating their endogenous inhibitor Spi2A (ref. 8). Our findings report a previously unknown, Stat3-regulated lysosomal-mediated pathway of cell death under physiological circumstances. We anticipate that these findings will be of major importance in the design of treatments for cancers such as breast, colon and liver, where cathepsins and Stat3 are commonly overexpressed and/or hyperactivated respectively.
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161
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Reiners JJ, Kleinman M, Kessel D, Mathieu PA, Caruso JA. Nonesterified cholesterol content of lysosomes modulates susceptibility to oxidant-induced permeabilization. Free Radic Biol Med 2011; 50:281-94. [PMID: 21074609 PMCID: PMC3018561 DOI: 10.1016/j.freeradbiomed.2010.11.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2010] [Revised: 10/06/2010] [Accepted: 11/04/2010] [Indexed: 11/21/2022]
Abstract
Reactive oxygen species (ROS) can induce lysosomal membrane permeabilization (LMP). Photoirradiation of murine hepatoma 1c1c7 cultures preloaded with the photosensitizer NPe6 generates singlet oxygen within acidic organelles and causes LMP and the activation of procaspases. Treatment with the cationic amphiphilic drugs (CADs) U18666A, imipramine, and clozapine stimulated the accumulation of filipin-stainable nonesterified cholesterol/sterols in late endosomes/lysosomes, but not in mitochondria. Concentration-response studies demonstrated an inverse relationship between lysosomal nonesterified cholesterol/sterol contents and susceptibility to NPe6 photoirradiation-induced intracellular membrane oxidation, LMP, and activation of procaspase-9 and -3. Similarly, the kinetics of restoration of NPe6 photoirradiation-induced LMP paralleled the losses of lysosomal cholesterol that occurred upon replating U18666A-treated cultures in CAD-free medium. Consistent with the oxidation of lysosomal cholesterol, filipin staining in U18666A-treated cultures progressively decreased with increasing photoirradiating light dose. U18666A also suppressed the induction of LMP and procaspase activation by exogenously added hydrogen peroxide. However, neither U18666A nor imipramine suppressed the induction of apoptosis by agents that did not directly induce LMP. These studies indicate that lysosomal nonesterified cholesterol/sterol content modulates susceptibility to ROS-induced LMP and possibly does so by being an alternative target for oxidants and lowering the probability of damage to other lysosomal membrane lipids and/or proteins.
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Affiliation(s)
- John J Reiners
- Institute of Environmental Health Sciences, Wayne State University, Detroit, MI 48201, USA.
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162
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Turner LS, Cheng JC, Beckham TH, Keane TE, Norris JS, Liu X. Autophagy is increased in prostate cancer cells overexpressing acid ceramidase and enhances resistance to C6 ceramide. Prostate Cancer Prostatic Dis 2010; 14:30-7. [PMID: 21116286 PMCID: PMC4203650 DOI: 10.1038/pcan.2010.47] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Acid ceramidase (AC) overexpression has been observed in prostate cancer cell lines and primary tumors, and contributes to resistance to chemotherapy and radiation. The consequence of AC overexpression is the ability to convert ceramide, which is often produced as a proapoptotic response to stress, to sphingosine, which can then be converted to the prosurvival molecule sphingosine-1-phosphate. In addition to their ability to metabolize ceramide produced in response to stress, we show here that prostate cancer cell lines overexpressing AC also have increased lysosomal density and increased levels of autophagy. Furthermore, pretreatment with 3-methyladenine restores sensitivity of these cells to treatment with C(6) ceramide. We also observed increased expression of the lysosomal stabilizing protein KIF5B and increased sensitivity to the lysosomotropic agent LCL385. Thus, we conclude that AC overexpression increases autophagy in prostate cancer cells, and that increased autophagy enhances resistance to ceramide.
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Affiliation(s)
- L S Turner
- Department of Biology, Francis Marion University, Florence, SC, USA.
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163
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Repnik U, Turk B. Lysosomal-mitochondrial cross-talk during cell death. Mitochondrion 2010; 10:662-9. [PMID: 20696281 DOI: 10.1016/j.mito.2010.07.008] [Citation(s) in RCA: 134] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2010] [Revised: 07/15/2010] [Accepted: 07/23/2010] [Indexed: 12/25/2022]
Abstract
Lysosomes are membrane-bound organelles, which contain an arsenal of different hydrolases, enabling them to act as the terminal degradative compartment of the endocytotic, phagocytic and autophagic pathways. During the last decade, it was convincingly shown that destabilization of lysosomal membrane and release of lysosomal content into the cytosol can initiate the lysosomal apoptotic pathway, which is dependent on mitochondria destabilization. The cleavage of BID to t-BID and degradation of anti-apoptotic BCL-2 proteins by lysosomal cysteine cathepsins were identified as links to the mitochondrial cytochrome c release, which eventually leads to caspase activation. There have also been reports about the involvement of lysosome destabilization and lysosomal proteases in the extrinsic apoptotic pathway, although the molecular mechanism is still under debate. In the present article, we discuss the cross-talk between lysosomes and mitochondria during apoptosis and its consequences for the fate of the cell.
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Affiliation(s)
- Urška Repnik
- Department of Biochemistry and Molecular and Structural Biology, Jozef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia.
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164
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Megalizzi V, Le Mercier M, Decaestecker C. Sigma receptors and their ligands in cancer biology: overview and new perspectives for cancer therapy. Med Res Rev 2010; 32:410-27. [DOI: 10.1002/med.20218] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Marie Le Mercier
- Department of Pathology; Erasme University Hospital; Brussels Belgium
| | - Christine Decaestecker
- Laboratory of Toxicology; Institute of Pharmacy; Brussels Belgium
- Laboratory of Image Synthesis and Analysis; Faculty of Applied Sciences; Université Libre de Bruxelles (ULB); Brussels Belgium
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165
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Groth-Pedersen L, Jäättelä M. Combating apoptosis and multidrug resistant cancers by targeting lysosomes. Cancer Lett 2010; 332:265-74. [PMID: 20598437 DOI: 10.1016/j.canlet.2010.05.021] [Citation(s) in RCA: 140] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2010] [Revised: 05/27/2010] [Accepted: 05/27/2010] [Indexed: 11/28/2022]
Abstract
Acquired therapy resistance is one of the prime obstacles for successful cancer treatment. Partial resistance is often acquired already during an early face of tumor development when genetic changes causing defects in classical caspase-dependent apoptosis pathway provide transformed cells with a growth advantage by protecting them against various apoptosis inducing stimuli including transforming oncogenes themselves and host immune system. Apoptosis defective cells are further selected during tumor progression and finally by apoptosis inducing treatments. Another form of resistance, multidrug resistance, arises during cancer treatment when cancer cells with effective efflux of cytotoxic agents escape the therapy. Remarkably, induction of lysosomal membrane permeabilization has recently emerged as an effective way to kill apoptosis resistant cancer cells and some lysosome targeting drugs can also re-sensitize multidrug resistant cells to classical chemotherapy. In this review, we highlight recent data on lysosomal cell death pathways and their implications for the future treatment of apoptosis defective and multidrug resistant aggressive tumors.
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Affiliation(s)
- Line Groth-Pedersen
- Pediatrics and Adolescent Medicine, The Juliane Marie Centre, University Hospital Rigshospitalet, Copenhagen, Denmark
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166
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Autophagy as a basis for the health-promoting effects of vitamin D. Trends Mol Med 2010; 16:295-302. [DOI: 10.1016/j.molmed.2010.04.005] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2010] [Revised: 04/19/2010] [Accepted: 04/20/2010] [Indexed: 12/31/2022]
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167
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Johansson AC, Appelqvist H, Nilsson C, Kågedal K, Roberg K, Ollinger K. Regulation of apoptosis-associated lysosomal membrane permeabilization. Apoptosis 2010; 15:527-40. [PMID: 20077016 PMCID: PMC2850995 DOI: 10.1007/s10495-009-0452-5] [Citation(s) in RCA: 340] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Lysosomal membrane permeabilization (LMP) occurs in response to a large variety of cell death stimuli causing release of cathepsins from the lysosomal lumen into the cytosol where they participate in apoptosis signaling. In some settings, apoptosis induction is dependent on an early release of cathepsins, while under other circumstances LMP occurs late in the cell death process and contributes to amplification of the death signal. The mechanism underlying LMP is still incompletely understood; however, a growing body of evidence suggests that LMP may be governed by several distinct mechanisms that are likely engaged in a death stimulus- and cell-type-dependent fashion. In this review, factors contributing to permeabilization of the lysosomal membrane including reactive oxygen species, lysosomal membrane lipid composition, proteases, p53, and Bcl-2 family proteins, are described. Potential mechanisms to safeguard lysosomal integrity and confer resistance to lysosome-dependent cell death are also discussed.
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168
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Gottlieb RA, Mentzer RM. Autophagy during cardiac stress: joys and frustrations of autophagy. Annu Rev Physiol 2010; 72:45-59. [PMID: 20148666 DOI: 10.1146/annurev-physiol-021909-135757] [Citation(s) in RCA: 207] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The study of autophagy has been transformed by the cloning of most genes in the pathway and the introduction of GFP-LC3 as a reporter to allow visual assessment of autophagy. The field of cardiac biology is not alone in attempting to understand the implications of autophagy. The purpose of this review is to address some of the controversies and conundrums associated with the evolving studies of autophagy in the heart. Autophagy is a cellular process involving a complex orchestration of regulatory gene products as well as machinery for assembly, selective targeting, and degradation of autophagosomes and their contents. Our understanding of the role of autophagy in human disease is rapidly evolving as investigators examine the process in different tissues and different pathophysiological contexts. In the field of heart disease, autophagy has been examined in the settings of ischemia and reperfusion, preconditioning, cardiac hypertrophy, and heart failure. This review addresses the role of autophagy in cardioprotection, the balance of catabolism and anabolism, the concept of mitochondrial quality control, and the implications of impaired autophagic flux or frustrated autophagy.
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Affiliation(s)
- Roberta A Gottlieb
- The BioScience Center, San Diego State University, San Diego, CA 92182, USA.
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169
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170
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Cagnol S, Chambard JC. ERK and cell death: mechanisms of ERK-induced cell death--apoptosis, autophagy and senescence. FEBS J 2009; 277:2-21. [PMID: 19843174 DOI: 10.1111/j.1742-4658.2009.07366.x] [Citation(s) in RCA: 999] [Impact Index Per Article: 66.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The Ras/Raf/extracellular signal-regulated kinase (ERK) signaling pathway plays a crucial role in almost all cell functions and therefore requires exquisite control of its spatiotemporal activity. Depending on the cell type and stimulus, ERK activity will mediate different antiproliferative events, such as apoptosis, autophagy and senescence in vitro and in vivo. ERK activity can promote either intrinsic or extrinsic apoptotic pathways by induction of mitochondrial cytochrome c release or caspase-8 activation, permanent cell cycle arrest or autophagic vacuolization. These unusual effects require sustained ERK activity in specific subcellular compartments and could depend on the presence of reactive oxygen species. We will summarize the mechanisms involved in Ras/Raf/ERK antiproliferative functions.
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Affiliation(s)
- Sebastien Cagnol
- Department of Anatomy and Cellular Biology, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, Quebec, Canada.
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171
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Abstract
Ras proteins traffic between the plasma membrane and endomembranes and signal from the cytosolic face of a variety of organelles. Palmitoylated N-Ras and H-Ras signal from early endosomes. A recent study reports that K-Ras resides on and signals from various types of endosomes, including late endosomes/lysosomes and multivesicular bodies.
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172
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Inoue J, Misawa A, Tanaka Y, Ichinose S, Sugino Y, Hosoi H, Sugimoto T, Imoto I, Inazawa J. Lysosomal-associated protein multispanning transmembrane 5 gene (LAPTM5) is associated with spontaneous regression of neuroblastomas. PLoS One 2009; 4:e7099. [PMID: 19787053 PMCID: PMC2746316 DOI: 10.1371/journal.pone.0007099] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2009] [Accepted: 08/05/2009] [Indexed: 01/07/2023] Open
Abstract
Background Neuroblastoma (NB) is the most frequently occurring solid tumor in children, and shows heterogeneous clinical behavior. Favorable tumors, which are usually detected by mass screening based on increased levels of catecholamines in urine, regress spontaneously via programmed cell death (PCD) or mature through differentiation into benign ganglioneuroma (GN). In contrast, advanced-type NB tumors often grow aggressively, despite intensive chemotherapy. Understanding the molecular mechanisms of PCD during spontaneous regression in favorable NB tumors, as well as identifying genes with a pro-death role, is a matter of urgency for developing novel approaches to the treatment of advanced-type NB tumors. Principal Findings We found that the expression of lysosomal associated protein multispanning transmembrane 5 (LAPTM5) was usually down-regulated due to DNA methylation in an NB cell-specific manner, but up-regulated in degenerating NB cells within locally regressing areas of favorable tumors detected by mass-screening. Experiments in vitro showed that not only a restoration of its expression but also the accumulation of LAPTM5 protein, was required to induce non-apoptotic cell death with autophagic vacuoles and lysosomal destabilization with lysosomal-membrane permeabilization (LMP) in a caspase-independent manner. While autophagy is a membrane-trafficking pathway to degrade the proteins in lysosomes, the LAPTM5-mediated lysosomal destabilization with LMP leads to an interruption of autophagic flux, resulting in the accumulation of immature autophagic vacuoles, p62/SQSTM1, and ubiqitinated proteins as substrates of autophagic degradation. In addition, ubiquitin-positive inclusion bodies appeared in degenerating NB cells. Conclusions We propose a novel molecular mechanism for PCD with the accumulation of autophagic vacuoles due to LAPTM5-mediated lysosomal destabilization. LAPTM5-induced cell death is lysosomal cell death with impaired autophagy, not cell death by autophagy, so-called autophagic cell death. Thus LAPTM5-mediated PCD is closely associated with the spontaneous regression of NBs and opens new avenues for exploring innovative clinical interventions for this tumor.
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Affiliation(s)
- Jun Inoue
- Department of Molecular Cytogenetics, Medical Research Institute and School of Biomedical Science, Tokyo Medical and Dental University, Tokyo, Japan
- Core Research for Evolutionary Science and Technology of the Japan Science and Technology Corporation, Saitama, Japan
| | - Akiko Misawa
- Department of Molecular Cytogenetics, Medical Research Institute and School of Biomedical Science, Tokyo Medical and Dental University, Tokyo, Japan
- Core Research for Evolutionary Science and Technology of the Japan Science and Technology Corporation, Saitama, Japan
| | - Yukichi Tanaka
- Division of Pathology, Kanagawa Children's Medical Center, Kanagawa, Japan
| | - Shizuko Ichinose
- Instrumental Analysis Research Center, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yuriko Sugino
- Department of Molecular Cytogenetics, Medical Research Institute and School of Biomedical Science, Tokyo Medical and Dental University, Tokyo, Japan
- Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Hajime Hosoi
- Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Tohru Sugimoto
- Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
- Saiseikai Shiga Hospital, Shiga, Japan
| | - Issei Imoto
- Department of Molecular Cytogenetics, Medical Research Institute and School of Biomedical Science, Tokyo Medical and Dental University, Tokyo, Japan
- Hard Tissue Genome research Center, Tokyo Medical and Dental University, Tokyo, Japan
- Core Research for Evolutionary Science and Technology of the Japan Science and Technology Corporation, Saitama, Japan
| | - Johji Inazawa
- Department of Molecular Cytogenetics, Medical Research Institute and School of Biomedical Science, Tokyo Medical and Dental University, Tokyo, Japan
- Hard Tissue Genome research Center, Tokyo Medical and Dental University, Tokyo, Japan
- 21st Century Center of Excellence Program for Molecular Destruction and Reconstitution of Tooth and Bone, Tokyo Medical and Dental University, Tokyo, Japan
- Global Center of Excellence (GCOE) Program, International Research Center for Molecular Science in Tooth and Bone Disease, Saitama, Japan
- Core Research for Evolutionary Science and Technology of the Japan Science and Technology Corporation, Saitama, Japan
- * E-mail:
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173
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Corcelle EA, Puustinen P, Jäättelä M. Apoptosis and autophagy: Targeting autophagy signalling in cancer cells -'trick or treats'? FEBS J 2009; 276:6084-96. [PMID: 19788415 DOI: 10.1111/j.1742-4658.2009.07332.x] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Macroautophagy (hereafter referred to as autophagy) is a tightly regulated lysosome-dependent catabolic pathway. During this process, cytosolic constituents are sequestered into autophagosomes, which subsequently fuse with lysosomes to become autolysosomes, where their contents are degraded. Autophagy contributes to the maintenance of the cellular energy homeostasis, to the clearance of damaged organelles and to adaptation to environmental stresses. Accordingly, autophagy defects have been linked to a wide range of human pathologies, including cancer. The recent discovery of several evolutionarily conserved genes involved in autophagosome formation has greatly stimulated the autophagy research, and the complex signalling networks regulating mammalian autophagy have begun to emerge. Here, we draw the current picture of signalling pathways connecting mitogenic and stress-induced signals to the initiation and maturation of autophagosomes and discuss the possibilities of their targeting as therapeutic adjuvants in anticancer therapy.
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Affiliation(s)
- Elisabeth A Corcelle
- Apoptosis Department and Centre for Genotoxic Stress Research, Institute of Cancer Biology, Danish Cancer Society, Copenhagen, Denmark
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174
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Saftig P, Klumperman J. Lysosome biogenesis and lysosomal membrane proteins: trafficking meets function. Nat Rev Mol Cell Biol 2009; 10:623-35. [PMID: 19672277 DOI: 10.1038/nrm2745] [Citation(s) in RCA: 1162] [Impact Index Per Article: 77.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Lysosomes are the primary catabolic compartments of eukaryotic cells. They degrade extracellular material that has been internalized by endocytosis and intracellular components that have been sequestered by autophagy. In addition, specialized cells contain lysosome-related organelles that store and secrete proteins for cell-type-specific functions. The functioning of a healthy cell is dependent on the proper targeting of newly synthesized lysosomal proteins. Accumulating evidence suggests that there are multiple lysosomal delivery pathways that together allow the regulated and sequential deposition of lysosomal components. The importance of lysosomal trafficking pathways is emphasized by recent findings that reveal new roles for lysosomal membrane proteins in cellular physiology and in an increasing number of diseases that are characterized by defects in lysosome biogenesis.
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Affiliation(s)
- Paul Saftig
- Department of Biochemistry, Christian-Albrechts University, Kiel, Germany.
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175
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Grønbaek K, Jäättelä M. Engaging the lysosomal compartment to combat B cell malignancies. J Clin Invest 2009; 119:2133-6. [PMID: 19620776 DOI: 10.1172/jci40259] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The combination of rituximab, a type I anti-CD20 mAb, with conventional chemotherapy has significantly improved the outcome of patients with B cell malignancies. Regardless of this success, many patients still relapse with therapy-resistant disease, highlighting the need for the development of mAbs with higher capacity to induce programmed cell death. The so-called type II anti-CD20 mAbs (e.g., tositumomab) that trigger caspase-independent B cell lymphoma cell death in vitro and show superior efficacy as compared with rituximab in eradicating target cells in mouse models are emerging as the next generation of therapeutic anti-CD20 mAbs. In this issue of the JCI, Ivanov and colleagues identify the lysosomal compartment as a target for type II mAbs (see the related article beginning on page 2143). These data encourage the further clinical development of type II mAbs as well as other lysosome-targeting drugs in the treatment of B cell malignancies.
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176
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Fehrenbacher N, Bar-Sagi D, Philips M. Ras/MAPK signaling from endomembranes. Mol Oncol 2009; 3:297-307. [PMID: 19615955 DOI: 10.1016/j.molonc.2009.06.004] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Accepted: 06/10/2009] [Indexed: 12/15/2022] Open
Abstract
Signal transduction along the Ras/MAPK pathway has been generally thought to take place at the plasma membrane. It is now evident that the plasma membrane is not the only platform capable of Ras/MAPK signal induction. Fusion of Ras with green fluorescent protein and the development of genetically encoded fluorescent probes for Ras activation have revealed signaling events on a variety of intracellular membranes including endosomes, the Golgi apparatus and the endoplasmic reticulum. Thus, the Ras/MAPK pathway is spatially compartmentalized within cells and this may afford greater complexity of signal output.
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177
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Aslan JE, You H, Williamson DM, Endig J, Youker RT, Thomas L, Shu H, Du Y, Milewski RL, Brush MH, Possemato A, Sprott K, Fu H, Greis KD, Runckel DN, Vogel A, Thomas G. Akt and 14-3-3 control a PACS-2 homeostatic switch that integrates membrane traffic with TRAIL-induced apoptosis. Mol Cell 2009; 34:497-509. [PMID: 19481529 DOI: 10.1016/j.molcel.2009.04.011] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2008] [Revised: 02/23/2009] [Accepted: 04/08/2009] [Indexed: 01/07/2023]
Abstract
TRAIL selectively kills diseased cells in vivo, spurring interest in this death ligand as a potential therapeutic. However, many cancer cells are resistant to TRAIL, suggesting the mechanism mediating TRAIL-induced apoptosis is complex. Here we identify PACS-2 as an essential TRAIL effector, required for killing tumor cells in vitro and virally infected hepatocytes in vivo. PACS-2 is phosphorylated at Ser437 in vivo, and pharmacologic and genetic studies demonstrate Akt is an in vivo Ser437 kinase. Akt cooperates with 14-3-3 to regulate the homeostatic and apoptotic properties of PACS-2 that mediate TRAIL action. Phosphorylated Ser437 binds 14-3-3 with high affinity, which represses PACS-2 apoptotic activity and is required for PACS-2 to mediate trafficking of membrane cargo. TRAIL triggers dephosphorylation of Ser437, reprogramming PACS-2 to promote apoptosis. Together, these studies identify the phosphorylation state of PACS-2 Ser437 as a molecular switch that integrates cellular homeostasis with TRAIL-induced apoptosis.
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Affiliation(s)
- Joseph E Aslan
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
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178
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Abstract
Apoptosis proceeds through a set of evolutionarily conserved processes that co-ordinate the elimination of damaged or unneeded cells. This program of cell death is carried out by organelle-directed regulators, including the Bcl-2 proteins, and ultimately executed by proteases of the caspase family. Although the biochemical mechanisms of apoptosis are increasingly understood, the underlying cell biology orchestrating programmed cell death remains enigmatic. In this review, we summarize the current understanding of Bcl-2 protein regulation and caspase activation while examining cell biological mechanisms and consequences of apoptotic induction. Organellar contributions to apoptotic induction include death receptor endocytosis, mitochondrial and lysosomal permeabilization, endoplasmic reticulum calcium release and fragmentation of the Golgi apparatus. These early apoptotic events are accompanied by stabilization of the microtubule cytoskeleton and translocation of organelles to the microtubule organizing center. Together, these phenomena establish a model of apoptotic induction whereby a cytoskeletal-dependent coalescence and 'scrambling' of organelles in the paranuclear region co-ordinates apoptotic communication, caspase activation and cell death.
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Affiliation(s)
- Joseph E Aslan
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
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179
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Watson CJ, Kreuzaler PA. The role of cathepsins in involution and breast cancer. J Mammary Gland Biol Neoplasia 2009; 14:171-9. [PMID: 19437107 DOI: 10.1007/s10911-009-9126-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2009] [Accepted: 04/23/2009] [Indexed: 12/13/2022] Open
Abstract
Cysteine cathepsins are proteolytic enzymes that reside in endolysosomal vesicles. Some are expressed constitutively while others are transcriptionally regulated. However, the expression and subcellular localization of cathepsins changes during cancer progression and cathepsins have been shown to be causally involved in various aspects of tumorigenesis including metastasis. The use of mouse models of breast cancer genetically ablated for cathepsin B has shown that both the growth of the primary tumor and the extend of lung metastasis is reduced by the loss of cathepsin B. The role of cathepsins in involution of the mammary gland has received little attention although it is clear that cathepsins are involved in tissue remodeling in the second phase of involution. We discuss here the roles of cathepsins and their endogenous inhibitors in breast tumorigenesis and post-lactational involution.
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180
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Cardoso CMP, Groth-Pedersen L, Høyer-Hansen M, Kirkegaard T, Corcelle E, Andersen JS, Jäättelä M, Nylandsted J. Depletion of kinesin 5B affects lysosomal distribution and stability and induces peri-nuclear accumulation of autophagosomes in cancer cells. PLoS One 2009; 4:e4424. [PMID: 19242560 PMCID: PMC2647799 DOI: 10.1371/journal.pone.0004424] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2008] [Accepted: 12/18/2008] [Indexed: 11/30/2022] Open
Abstract
Background Enhanced lysosomal trafficking is associated with metastatic cancer. In an
attempt to discover cancer relevant lysosomal motor proteins, we compared
the lysosomal proteomes from parental MCF-7 breast cancer cells with those
from highly invasive MCF-7 cells that express an active form of the ErbB2
(ΔN-ErbB2). Methodology/Principal Findings Mass spectrometry analysis identified kinesin heavy chain protein KIF5B as
the only microtubule motor associated with the lysosomes in MCF-7 cells, and
ectopic ΔN-ErbB2 enhanced its lysosomal association. KIF5B
associated with lysosomes also in HeLa cervix carcinoma cells as analyzed by
subcellular fractionation. The depletion of KIF5B triggered peripheral
aggregations of lysosomes followed by lysosomal destabilization, and cell
death in HeLa cells. Lysosomal exocytosis in response to plasma membrane
damage as well as fluid phase endocytosis functioned, however, normally in
these cells. Both HeLa and MCF-7 cells appeared to express similar levels of
the KIF5B isoform but the death phenotype was weaker in KIF5B-depleted MCF-7
cells. Surprisingly, KIF5B depletion inhibited the rapamycin-induced
accumulation of autophagosomes in MCF-7 cells. In KIF5B-depleted cells the
autophagosomes formed and accumulated in the close proximity to the Golgi
apparatus, whereas in the control cells they appeared uniformly distributed
in the cytoplasm. Conclusions/Significance Our data identify KIF5B as a cancer relevant lysosomal motor protein with
additional functions in autophagosome formation.
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Affiliation(s)
- Carla M P Cardoso
- Center for Neuroscience and Cell Biology, Faculty of Medicine, University of Coimbra, Coimbra, Portugal
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181
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Kirkegaard T, Jäättelä M. Lysosomal involvement in cell death and cancer. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2008; 1793:746-54. [PMID: 18948147 DOI: 10.1016/j.bbamcr.2008.09.008] [Citation(s) in RCA: 285] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2008] [Revised: 07/10/2008] [Accepted: 09/17/2008] [Indexed: 11/16/2022]
Abstract
Lysosomes, with their arsenal of degradative enzymes are increasingly becoming an area of interest in the field of oncology. The changes induced in this compartment upon transformation are numerous and whereas most are viewed as pro-oncogenic the same processes also render cancer cells susceptible to lysosomal death pathways. This review will provide an overview of the pro- and anti-oncogenic potential of this compartment and how these might be exploited for cancer therapy, with special focus on lysosomal death pathways.
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Affiliation(s)
- Thomas Kirkegaard
- Danish Cancer Society, Department of Apoptosis, Institute of Cancer Biology, Copenhagen, Denmark
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