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Showing papers by "Guido Kroemer published in 2012"


Journal ArticleDOI
TL;DR: These guidelines are presented for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes.
Abstract: In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field.

4,316 citations


Journal ArticleDOI
TL;DR: A functional classification of cell death subroutines is proposed that applies to both in vitro and in vivo settings and includes extrinsic apoptosis, caspase-dependent or -independent intrinsic programmed cell death, regulated necrosis, autophagic cell death and mitotic catastrophe.
Abstract: In 2009, the Nomenclature Committee on Cell Death (NCCD) proposed a set of recommendations for the definition of distinct cell death morphologies and for the appropriate use of cell death-related terminology, including 'apoptosis', 'necrosis' and 'mitotic catastrophe'. In view of the substantial progress in the biochemical and genetic exploration of cell death, time has come to switch from morphological to molecular definitions of cell death modalities. Here we propose a functional classification of cell death subroutines that applies to both in vitro and in vivo settings and includes extrinsic apoptosis, caspase-dependent or -independent intrinsic apoptosis, regulated necrosis, autophagic cell death and mitotic catastrophe. Moreover, we discuss the utility of expressions indicating additional cell death modalities. On the basis of the new, revised NCCD classification, cell death subroutines are defined by a series of precise, measurable biochemical features.

2,238 citations


Journal ArticleDOI
12 Apr 2012-Oncogene
TL;DR: A systematic discussion of the mechanisms that account for the cisplatin-resistant phenotype of tumor cells are described and the development of chemosensitization strategies constitute a goal with important clinical implications.
Abstract: Platinum-based drugs, and in particular cis-diamminedichloroplatinum(II) (best known as cisplatin), are employed for the treatment of a wide array of solid malignancies, including testicular, ovarian, head and neck, colorectal, bladder and lung cancers. Cisplatin exerts anticancer effects via multiple mechanisms, yet its most prominent (and best understood) mode of action involves the generation of DNA lesions followed by the activation of the DNA damage response and the induction of mitochondrial apoptosis. Despite a consistent rate of initial responses, cisplatin treatment often results in the development of chemoresistance, leading to therapeutic failure. An intense research has been conducted during the past 30 years and several mechanisms that account for the cisplatin-resistant phenotype of tumor cells have been described. Here, we provide a systematic discussion of these mechanism by classifying them in alterations (1) that involve steps preceding the binding of cisplatin to DNA (pre-target resistance), (2) that directly relate to DNA-cisplatin adducts (on-target resistance), (3) concerning the lethal signaling pathway(s) elicited by cisplatin-mediated DNA damage (post-target resistance) and (4) affecting molecular circuitries that do not present obvious links with cisplatin-elicited signals (off-target resistance). As in some clinical settings cisplatin constitutes the major therapeutic option, the development of chemosensitization strategies constitute a goal with important clinical implications.

2,026 citations


Journal ArticleDOI
TL;DR: Mitochondria can emit danger signals that alert the cell or the whole organism of perturbations in homeostasis, hence promoting the induction of cell-intrinsic or systemic adaptive responses, respectively, and can be considered as master regulators of danger signalling.
Abstract: Throughout more than 1.5 billion years of obligate endosymbiotic co-evolution, mitochondria have developed not only the capacity to control distinct molecular cascades leading to cell death but also the ability to sense (and react to) multiple situations of cellular stress, including viral infection. In addition, mitochondria can emit danger signals that alert the cell or the whole organism of perturbations in homeostasis, hence promoting the induction of cell-intrinsic or systemic adaptive responses, respectively. As such, mitochondria can be considered as master regulators of danger signalling.

611 citations


Journal ArticleDOI
TL;DR: The molecular and cellular circuitries whereby cytotoxic agents can activate the immune system against cancer, and their therapeutic implications, are discussed.
Abstract: A crucial role of the immune system in cancer progression and response to therapy has recently emerged. Here, Galluzzi and colleagues discuss the immune parameters that may predict the therapeutic response of patients to chemotherapeutics, and review the mechanisms by which current antineoplastic agents activate the immune system against cancer.

591 citations


Journal ArticleDOI
TL;DR: The inhibition of inflammasomes or neutralization of their products, mainly interleukin 1β (IL-1β) and IL-18, has profound effects on carcinogenesis and tumor progression and is promising therapeutic targets in cancer-related clinical conditions.
Abstract: In the complex interplay between malignant cells and their microenvironment, caspase-1 activation complexes (inflammasomes) have contrasting roles. Inflammasomes may operate at the cell-autonomous level to eliminate malignant precursors through programmed cell death or, conversely, may stimulate the production of trophic factors for cancer cells and their stroma. In inflammatory cells, caspase-1 activation can fuel a cycle that leads to sterile inflammation and carcinogenesis, whereas in antigen-presenting cells, inflammasomes can stimulate anticancer immune responses. The inhibition of inflammasomes or neutralization of their products, mainly interleukin 1β (IL-1β) and IL-18, has profound effects on carcinogenesis and tumor progression. Thus, inflammasomes are promising therapeutic targets in cancer-related clinical conditions. Here we discuss present and future indications for the clinical use of inflammasome inhibitors.

513 citations


Journal ArticleDOI
TL;DR: An overview of the molecular mechanisms that enable mitochondria to sustain cell survival, coordinate stress responses, and mediate cell death are provided, linking these pathways—whenever relevant—to cardiovascular health and disease.
Abstract: Since the discovery that mitochondrial membrane permeabilization represents a critical step in the regulation of intrinsic apoptosis, mitochondria have been viewed as pluripotent organelles, controlling cell death as well as several aspects of cell survival. Mitochondria constitute the most prominent source of ATP and are implicated in multiple anabolic and catabolic circuitries. In addition, mitochondria coordinate cell-wide stress responses, such as autophagy, and control nonapoptotic cell death routines, such as regulated necrosis. Thus, mitochondria seem to regulate a continuum of cellular functions, spanning from physiological metabolism to stress responses and death. The involvement of mitochondria in both vital and lethal processes is crucial for both embryonic and postembryonic development, as well as for the maintenance of adult tissue homeostasis. In line with this notion, primary mitochondrial defects or alterations in the signaling pathways that converge on or emanate from mitochondria underpin a large number of human diseases, including premature aging, neurodegenerative disorders, cardiovascular disorders, and cancer. Here, we provide an overview of the molecular mechanisms that enable mitochondria to sustain cell survival, coordinate stress responses, and mediate cell death, linking these pathways--whenever relevant--to cardiovascular health and disease.

422 citations


Journal ArticleDOI
Laura Senovilla1, Laura Senovilla2, Laura Senovilla3, Ilio Vitale1, Ilio Vitale2, Ilio Vitale3, Isabelle Martins1, Isabelle Martins2, Isabelle Martins3, Maximilien Tailler3, Maximilien Tailler2, Maximilien Tailler1, Claire Pailleret1, Claire Pailleret2, Claire Pailleret3, Mickaël Michaud1, Mickaël Michaud2, Mickaël Michaud3, Lorenzo Galluzzi3, Lorenzo Galluzzi2, Lorenzo Galluzzi1, Sandy Adjemian3, Sandy Adjemian2, Sandy Adjemian1, Oliver Kepp1, Oliver Kepp2, Oliver Kepp3, Mireia Niso-Santano1, Mireia Niso-Santano2, Mireia Niso-Santano3, Shensi Shen3, Shensi Shen2, Shensi Shen1, Guillermo Mariño3, Guillermo Mariño2, Guillermo Mariño1, Alfredo Criollo1, Alfredo Criollo2, Alfredo Criollo3, Alice Boilève3, Alice Boilève2, Alice Boilève1, Bastien Job1, Sylvain Ladoire2, François Ghiringhelli2, Antonella Sistigu1, Antonella Sistigu3, Antonella Sistigu2, Takahiro Yamazaki3, Takahiro Yamazaki2, Takahiro Yamazaki1, Santiago Rello-Varona3, Santiago Rello-Varona1, Santiago Rello-Varona2, Clara Locher1, Clara Locher2, Clara Locher3, Vichnou Poirier-Colame3, Vichnou Poirier-Colame2, Vichnou Poirier-Colame1, Monique Talbot1, Alexander Valent, Francesco Berardinelli4, Antonio Antoccia4, Fabiola Ciccosanti, Gian Maria Fimia, Mauro Piacentini5, Antonio Fueyo6, Nicole L Messina7, Nicole L Messina8, Ming Li7, Christopher J. Chan7, Christopher J. Chan9, Verena Sigl10, Guillaume Pourcher3, Guillaume Pourcher2, Christoph Ruckenstuhl, Didac Carmona-Gutierrez, Vladimir Lazar1, Josef M. Penninger10, Frank Madeo, Carlos López-Otín6, Mark J. Smyth7, Mark J. Smyth9, Laurence Zitvogel, Maria Castedo1, Maria Castedo2, Maria Castedo3, Guido Kroemer 
28 Sep 2012-Science
TL;DR: It is reported that hyperploid cancer cells become immunogenic because of a constitutive endoplasmic reticulum stress response resulting in the aberrant cell surface exposure of calreticulin, which causes recognition of cancer cells in mice by the host immune system.
Abstract: Cancer cells accommodate multiple genetic and epigenetic alterations that initially activate intrinsic (cell-autonomous) and extrinsic (immune-mediated) oncosuppressive mechanisms. Only once these barriers to oncogenesis have been overcome can malignant growth proceed unrestrained. Tetraploidization can contribute to oncogenesis because hyperploid cells are genomically unstable. We report that hyperploid cancer cells become immunogenic because of a constitutive endoplasmic reticulum stress response resulting in the aberrant cell surface exposure of calreticulin. Hyperploid, calreticulin-exposing cancer cells readily proliferated in immunodeficient mice and conserved their increased DNA content. In contrast, hyperploid cells injected into immunocompetent mice generated tumors only after a delay, and such tumors exhibited reduced DNA content, endoplasmic reticulum stress, and calreticulin exposure. Our results unveil an immunosurveillance system that imposes immunoselection against hyperploidy in carcinogen- and oncogene-induced cancers.

350 citations


Journal ArticleDOI
TL;DR: Rec retrospective clinical analyses revealed that the administration of the CG digoxin during chemotherapy had a positive impact on overall survival in cohorts of breast, colorectal, head and neck, and hepatocellular carcinoma patients, especially when they were treated with agents other than anthracyclines and oxaliplatin.
Abstract: Some successful chemotherapeutics, notably anthracyclines and oxaliplatin, induce a type of cell stress and death that is immunogenic, hence converting the patient's dying cancer cells into a vaccine that stimulates antitumor immune responses. By means of a fluorescence microscopy platform that allows for the automated detection of the biochemical hallmarks of such a peculiar cell death modality, we identified cardiac glycosides (CGs) as exceptionally efficient inducers of immunogenic cell death, an effect that was associated with the in- hibition of the plasma membrane Na + - and K + -dependent adenosine triphosphatase (Na + /K + -ATPase). CGs ex- acerbated the antineoplastic effects of DNA-damaging agents in immunocompetent but not immunodeficient mice. Moreover, cancer cells succumbing to a combination of chemotherapy plus CGs could vaccinate synge- neic mice against a subsequent challenge with living cells of the same type. Finally, retrospective clinical analy- ses revealed that the administration of the CG digoxin during chemotherapy had a positive impact on overall survival in cohorts of breast, colorectal, head and neck, and hepatocellular carcinoma patients, especially when they were treated with agents other than anthracyclines and oxaliplatin.

345 citations


Journal ArticleDOI
TL;DR: The therapeutic potential of agents that target PD-1 or its ligand PD-L1 in patients with advanced cancer, even individuals with lung or brain metastases is highlighted, and this clinical breakthrough will open novel avenues for cancer immunotherapy.
Abstract: Tumors have developed multiple immunosuppressive mechanisms to turn down the innate and the effector arms of the immune system, thus compromising most of the immunotherapeutic strategies that have been proposed during the last decade Right after the pioneering success of Ipilimumab (anti-CTLA4) in metastatic melanoma, several groups have conducted trials aiming at subverting other immune checkpoints Two articles that recently appeared in the New England Journal of Medicine1,2 highlight the therapeutic potential of agents that target PD-1 or its ligand PD-L1 in patients with advanced cancer, even individuals with lung or brain metastases If confirmed, this clinical breakthrough will open novel avenues for cancer immunotherapy

338 citations


Journal ArticleDOI
TL;DR: It is found that P2X7 exhibits significant growth-promoting effects in vivo, and immunohistochemistry revealed strong P2x7 positivity in several human cancers.
Abstract: The P2X7 receptor is an ATP-gated ion channel known for its cytotoxic activity. However, recent evidence suggests a role for P2X7 in cell proliferation. Here, we found that P2X7 exhibits significant growth-promoting effects in vivo. Human embryonic kidney cells expressing P2X7 exhibited a more tumorigenic and anaplastic phenotype than control cells in vivo, and the growth rate and size of these tumors were significantly reduced by intratumoral injection of the P2X7 inhibitor-oxidized ATP. The accelerated growth of P2X7-expressing tumors was characterized by increased proliferation, reduced apoptosis, and a high level of activated transcription factor NFATc1. These tumors also showed a more developed vascular network than control tumors and secreted elevated amounts of VEGF. The growth and neoangiogenesis of P2X7-expressing tumors was blocked by intratumoral injection of the VEGF-blocking antibody Avastin (bevacizumab), pharmacologic P2X7 blockade, or P2X7 silencing in vivo. Immunohistochemistry revealed strong P2X7 positivity in several human cancers. Together, our findings provide direct evidence that P2X7 promotes tumor growth in vivo.

Journal ArticleDOI
TL;DR: In this paper, the authors systematically evaluated whether established or prospective anticancer agents may induce autophagic cell death, and found that not a single one turned out to kill tumor cells through the induction of autophagy.
Abstract: In the mammalian system, cell death is often preceded or accompanied by autophagic vacuolization, a finding that initially led to the widespread belief that so-called "autophagic cell death" would be mediated by autophagy. Thanks to the availability of genetic tools to disable the autophagic machinery, it has become clear over recent years that autophagy usually constitutes a futile attempt of dying cells to adapt to lethal stress rather than a mechanism to execute a cell death program. Recently, we systematically addressed the question as to whether established or prospective anticancer agents may induce "autophagic cell death". Although a considerable portion among the 1,400 compounds that we evaluated induced autophagic puncta and actually increased autophagic flux, not a single one turned out to kill tumor cells through the induction of autophagy. Thus, knockdown of essential autophagy genes (such as ATG5 and ATG7) failed to prevent and rather accelerated chemotherapy-induced cell death, in spite of the fact that this manipulation efficiently inhibits autophagosome formation. Herein, we review these finding and--polemically--raise doubts as to the very existence of "autophagic cell death".

Journal ArticleDOI
TL;DR: The latest advances on the use of cyclophosphamide, doxorubicin, epirubic in, oxaliplatin, and mitoxantrone in cancer patients are summarized, discussing high-impact studies that have been published during the last 13 months as well as clinical trials that have be initiated in the same period to assess the antineoplastic profile of these immunogenic drugs as off-label therapeutic interventions.
Abstract: Accumulating evidence suggests that the clinical efficacy of selected anticancer drugs, including conventional chemotherapeutics as well as targeted anticancer agents, originates (at least in part) from their ability to elicit a novel or reinstate a pre-existing tumor-specific immune response. One of the mechanisms whereby chemotherapy can stimulate the immune system to recognize and destroy malignant cells is commonly known as immunogenic cell death (ICD). Cancer cells succumbing to ICD are de facto converted into an anticancer vaccine and as such elicit an adaptive immune response. Several common chemotherapeutics share the ability of triggering ICD, as demonstrated in vaccination experiments relying on immunocompetent mice and syngeneic cancer cells. A large number of ongoing clinical trials involve such ICD inducers, often (but not always) as they are part of the gold standard therapeutic approach against specific neoplasms. In this Trial Watch, we summarize the latest advances on the use of cyclophosphamide, doxorubicin, epirubicin, oxaliplatin, and mitoxantrone in cancer patients, discussing high-impact studies that have been published during the last 13 months as well as clinical trials that have been initiated in the same period to assess the antineoplastic profile of these immunogenic drugs as off-label therapeutic interventions.


Journal ArticleDOI
TL;DR: The results of recently completed clinical trials are summarized, the progress of ongoing studies that have evaluated/are evaluating DC-based interventions for cancer therapy are discussed and personalized combination strategies that would extend the benefit of DC- based immunotherapy to a larger patient population are discussed.
Abstract: Dendritic cells (DCs) occupy a privileged position at the interface between innate and adaptive immunity, orchestrating a large panel of responses to both physiological and pathological cues. In particular, whereas the presentation of antigens by immature DCs generally results in the development of immunological tolerance, mature DCs are capable of priming robust, and hence therapeutically relevant, adaptive immune responses. In line with this notion, functional defects in the DC compartment have been shown to etiologically contribute to pathological conditions including (but perhaps not limited to) infectious diseases, allergic and autoimmune disorders, graft rejection and cancer. Thus, the possibility of harnessing the elevated immunological potential of DCs for anticancer therapy has attracted considerable interest from both researchers and clinicians over the last decade. Alongside, several methods have been developed not only to isolate DCs from cancer patients, expand them, load them with tumor-associated antigens and hence generate highly immunogenic clinical grade infusion products, but also to directly target DCs in vivo. This intense experimental effort has culminated in 2010 with the approval by the US FDA of a DC-based preparation (sipuleucel-T, Provenge®) for the treatment of asymptomatic or minimally symptomatic metastatic castration-refractory prostate cancer. As an update to the latest Trial Watch dealing with this exciting field of research (October 2012), here we summarize recent advances in DC-based anticancer regimens, covering both high-impact studies that have been published during the last 13 mo and clinical trials that have been launched in the same period to assess the antineoplastic potential of this variant of cellular immunotherapy.

Journal ArticleDOI
TL;DR: The results of clinical trials that have evaluated/are evaluating the prognostic and predictive value of the immune infiltrate in the context of solid malignancies are summarized.
Abstract: Solid tumors are constituted of a variety of cellular components, including bona fide malignant cells as well as endothelial, structural and immune cells. On one hand, the tumor stroma exerts major pro-tumorigenic and immunosuppressive functions, reflecting the capacity of cancer cells to shape the microenvironment to satisfy their own metabolic and immunological needs. On the other hand, there is a component of tumor-infiltrating leucocytes (TILs) that has been specifically recruited in the attempt to control tumor growth. Along with the recognition of the critical role played by the immune system in oncogenesis, tumor progression and response to therapy, increasing attention has been attracted by the potential prognostic and/or predictive role of the immune infiltrate in this setting. Data from large clinical studies demonstrate indeed that a robust infiltration of neoplastic lesions by specific immune cell populations, including (but not limited to) CD8+ cytotoxic T lymphocytes, Th1 and Th17 CD4+ T cells, natural killer cells, dendritic cells, and M1 macrophages constitutes an independent prognostic indicator in several types of cancer. Conversely, high levels of intratumoral CD4+CD25+FOXP3+ regulatory T cells, Th2 CD4+ T cells, myeloid-derived suppressor cells, M2 macrophages and neutrophils have frequently been associated with dismal prognosis. So far, only a few studies have addressed the true predictive potential of TILs in cancer patients, generally comforting the notion that—at least in some clinical settings—the immune infiltrate can reliably predict if a specific patient will respond to therapy or not. In this Trial Watch, we will summarize the results of clinical trials that have evaluated/are evaluating the prognostic and predictive value of the immune infiltrate in the context of solid malignancies.

Journal ArticleDOI
TL;DR: This Trial Watch will summarize the results of recently completed clinical trials and discuss the progress of ongoing studies that have evaluated/are evaluating FDA-approved TLR agonists as off-label medications for cancer therapy.
Abstract: Toll-like receptors (TLRs) have first been characterized for their capacity to detect conserved microbial components like lipopolysaccharide (LPS) and double-stranded RNA, resulting in the elicitation of potent (innate) immune responses against invading pathogens. More recently, TLRs have also been shown to promote the activation of the cognate immune system against cancer cells. Today, only three TLR agonists are approved by FDA for use in humans: the bacillus Calmette-Guerin (BCG), monophosphoryl lipid A (MPL) and imiquimod. BCG (an attenuated strain of Mycobacterium bovis) is mainly used as a vaccine against tuberculosis, but also for the immunotherapy of in situ bladder carcinoma. MPL (derived from the LPS of Salmonella minnesota) is included in the formulation of Cervarix®, a vaccine against human papillomavirus-16 and -18. Imiquimod (a synthetic imidazoquinoline) is routinely employed for actinic keratosis, superficial basal cell carcinoma, and external genital warts (condylomata acuminata). In this Trial Watch, we will summarize the results of recently completed clinical trials and discuss the progress of ongoing studies that have evaluated/are evaluating FDA-approved TLR agonists as off-label medications for cancer therapy.

Journal ArticleDOI
TL;DR: The role of TLRs in innate and cognate immunity is presented and the progress of clinical studies evaluating the safety and efficacy of experimental TLR agonists as immunostimulatory agents for oncological indications is discussed.
Abstract: Toll-like receptors (TLRs) are prototypic pattern recognition receptors (PRRs) best known for their ability to activate the innate immune system in response to conserved microbial components such as lipopolysaccharide and double-stranded RNA. Accumulating evidence indicates that the function of TLRs is not restricted to the elicitation of innate immune responses against invading pathogens. TLRs have indeed been shown to participate in tissue repair and injury-induced regeneration as well as in adaptive immune responses against cancer. In particular, TLR4 signaling appears to be required for the efficient processing and cross-presentation of cell-associated tumor antigens by dendritic cells, which de facto underlie optimal therapeutic responses to some anticancer drugs. Thus, TLRs constitute prominent therapeutic targets for the activation/intensification of anticancer immune responses. In line with this notion, long-used preparations such as the Coley toxin (a mixture of killed Streptococcus pyogenes and Serratia marcescens bacteria) and the bacillus Calmette-Guerin (BCG, an attenuated strain of Mycobacterium bovis originally developed as a vaccine against tuberculosis), both of which have been associated with consistent anticancer responses, potently activate TLR2 and TLR4 signaling. Today, besides BCG, only one TLR agonist is FDA-approved for therapeutic use in cancer patients: imiquimod. In this Trial Watch, we will briefly present the role of TLRs in innate and cognate immunity and discuss the progress of clinical studies evaluating the safety and efficacy of experimental TLR agonists as immunostimulatory agents for oncological indications.

Journal ArticleDOI
TL;DR: The results of recent clinical trials that have evaluated/are evaluating purified peptides or full-length proteins as therapeutic interventions against cancer are summarized.
Abstract: Prophylactic vaccination constitutes one of the most prominent medical achievements of history. This concept was first demonstrated by the pioneer work of Edward Jenner, dating back to the late 1790s, after which an array of preparations that confer life-long protective immunity against several infectious agents has been developed. The ensuing implementation of nation-wide vaccination programs has de facto abated the incidence of dreadful diseases including rabies, typhoid, cholera and many others. Among all, the most impressive result of vaccination campaigns is surely represented by the eradication of natural smallpox infection, which was definitively certified by the WHO in 1980. The idea of employing vaccines as anticancer interventions was first theorized in the 1890s by Paul Ehrlich and William Coley. However, it soon became clear that while vaccination could be efficiently employed as a preventive measure against infectious agents, anticancer vaccines would have to (1) operate as therapeutic, rather than preventive, interventions (at least in the vast majority of settings), and (2) circumvent the fact that tumor cells often fail to elicit immune responses. During the past 30 y, along with the recognition that the immune system is not irresponsive to tumors (as it was initially thought) and that malignant cells express tumor-associated antigens whereby they can be discriminated from normal cells, considerable efforts have been dedicated to the development of anticancer vaccines. Some of these approaches, encompassing cell-based, DNA-based and purified component-based preparations, have already been shown to exert conspicuous anticancer effects in cohorts of patients affected by both hematological and solid malignancies. In this Trial Watch, we will summarize the results of recent clinical trials that have evaluated/are evaluating purified peptides or full-length proteins as therapeutic interventions against cancer.

Journal ArticleDOI
TL;DR: Results indicate that micron nuclei can be subjected to autophagic degradation and it can be speculated that removal of micronuclei may contribute to the genome-stabilizing effects of autophagy.
Abstract: Macroautophagy is known to participate in the quality control and turnover of cytoplasmic organelles, yet there is little evidence that macroautophagy targets nuclei in mammalian cells. Here, we investigated whether autophagy may target micronuclei, which arise as a result of deficient bipolar chromosome segregation in cells exposed to cell cycle perturbations. After removal of several distinct cell cycle blockers (nocodazole, cytochalasin D, hydroxyurea or SP600125), cells manifested an increase in the frequency of micronuclei (positive for histone H2B-RFP) as well as an increase in autophagic puncta (positive for GFP-LC3) over several days. A small but significant percentage of micronuclei co-localized with GFP-LC3 in autophagy-competent cells and this co-localization was lost after knockdown of ATG5 or ATG7. Electron microscopy analyses confirmed autophagic sequestration of micronuclei. "Autophagic micronuclei" (GFP-LC3⁺) were also decorated with p62/SQSTM1, while non-autophagic (GFP-LC3⁻) micronuclei where p62/SQSTM1 negative. In addition, GFP-LC3⁺ micronuclei exhibited signs of envelope degradation and γH2AX⁺ DNA damage foci, yet stained less intensively for chromatin markers, whereas GFP-LC3⁻ micronuclei were surrounded by an intact envelope and rarely exhibited markers or DNA damage. These results indicate that micronuclei can be subjected to autophagic degradation. Moreover, it can be speculated that removal of micronuclei may contribute to the genome-stabilizing effects of autophagy.

Journal ArticleDOI
TL;DR: This Trial Watch will review and discuss the clinical progress of the most important mAbs that are have entered clinical trials after January 2008 and some of these antibodies, which are thought to facilitate tumor eradication by initiating or sustaining a tumor-specific immune response, have already entering clinical trials.
Abstract: Since the advent of hybridoma technology, dating back to 1975, monoclonal antibodies have become an irreplaceable diagnostic and therapeutic tool for a wide array of human diseases. During the last 15 years, several monoclonal antibodies (mAbs) have been approved by FDA for cancer therapy. These mAbs are designed to (1) activate the immune system against tumor cells, (2) inhibit cancer cell-intrinsic signaling pathways, (3) bring toxins in the close proximity of cancer cells, or (4) interfere with the tumor-stroma interaction. More recently, major efforts have been made for the development of immunostimulatory mAbs that either enhance cancer-directed immune responses or limit tumor- (or therapy-) driven immunosuppression. Some of these antibodies, which are thought to facilitate tumor eradication by initiating or sustaining a tumor-specific immune response, have already entered clinical trials. In this Trial Watch, we will review and discuss the clinical progress of the most important mAbs that are have entered clinical trials after January 2008.

Journal ArticleDOI
TL;DR: A signalling pathway is delineated that leads to calreticulin (CRT) exposure and ATP release by cancer cells that succumb to photodynamic therapy (PTD), thereby providing fresh insights into the molecular regulation of immunogenic cell death (ICD).
Abstract: The textbook notion that apoptosis would always take place unrecognized by the immune system has recently been invalidated (Zitvogel et al, 2010; Galluzzi et al, 2012). Thus, in specific circumstances (in particular in response to anthracyclines, oxaliplatin, and γ irradiation), cancer cells can enter a lethal stress pathway linked to the emission of a spatiotemporally defined combination of signals that is decoded by the immune system to activate tumour-specific immune responses (Zitvogel et al, 2010). These signals include the pre-apoptotic exposure of intracellular proteins such as the endoplasmic reticulum (ER) chaperon CRT and the heat-shock protein HSP90 at the cell surface, the pre-apoptotic secretion of ATP, and the post-apoptotic release of the nuclear protein HMGB1 (Zitvogel et al, 2010). Together, these processes (and perhaps others) constitute the molecular determinants of ICD. In this issue of The EMBO Journal, Garg et al (2012) add hypericin-based PTD (Hyp-PTD) to the list of bona fide ICD inducers and convincingly link Hyp-PTD-elicited ICD to the functional activation of the immune system. Moreover, Garg et al (2012) demonstrate that Hyp-PDT stimulates ICD via signalling pathways that overlap with—but are not identical to—those elicited by anthracyclines, which constitute the first ICD inducers to be characterized (Casares et al, 2005; Zappasodi et al, 2010; Fucikova et al, 2011). Intrigued by the fact that the ER stress response is required for anthracycline-induced ICD (Panaretakis et al, 2009), Garg et al (2012) decided to investigate the immunogenicity of Hyp-PDT (which selectively targets the ER). Hyp-PDT potently stimulated CRT exposure and ATP release in human bladder carcinoma T24 cells. As a result, T24 cells exposed to Hyp-PDT (but not untreated cells) were engulfed by Mf4/4 macrophages and human dendritic cells (DCs), the most important antigen-presenting cells in antitumour immunity. Similarly, murine colon carcinoma CT26 cells succumbing to Hyp-PDT (but not cells dying in response to the unspecific ER stressor tunicamycin) were preferentially phagocytosed by murine JAWSII DCs, and efficiently immunized syngenic BALB/c mice against a subsequent challenge with living cells of the same type. Of note, contrarily to T24 cells treated with lipopolysaccharide (LPS) or dying from accidental necrosis, T24 cells exposed to Hyp-PDT activated DCs while eliciting a peculiar functional profile, featuring high levels of NO production and absent secretion of immunosuppressive interleukin-10 (IL-10) (Garg et al, 2012). Moreover upon co-culture with Hyp-PDT-treated T24 cells, human DCs were found to secrete high levels of IL-1β, a cytokine that is required for the adequate polarization of interferon γ (IFNγ)-producing antineoplastic CD8+ T cells (Aymeric et al, 2010). Taken together, these data demonstrate that Hyp-PDT induces bona fide ICD, eliciting an antitumour immune response. By combining pharmacological and genetic approaches, Garg et al (2012) then investigated the molecular cascades that are required for Hyp-PDT-induced CRT exposure and ATP release. They found that CRT exposure triggered by Hyp-PDT requires reactive oxygen species (as demonstrated with the 1O2 quencher L-histidine), class I phosphoinositide-3-kinase (PI3K) activity (as shown with the chemical inhibitor wortmannin and the RNAi-mediated depletion of the catalytic PI3K subunit p110), the actin cytoskeleton (as proven with the actin inhibitor latrunculin B), the ER-to-Golgi anterograde transport (as shown using brefeldin A), the ER stress-associated kinase PERK, the pro-apoptotic molecules BAX and BAK as well as the CRT cell surface receptor CD91 (as demonstrated by their knockout or RNAi-mediated depletion). However, there were differences in the signalling pathways leading to CRT exposure in response to anthracyclines (Panaretakis et al, 2009) and Hyp-PDT (Garg et al, 2012). In contrast to the former, the latter was not accompanied by the exposure of the ER chaperon ERp57, and did not require eIF2α phosphorylation (as shown with non-phosphorylatable eIF2α mutants), caspase-8 activity (as shown with the pan-caspase blocker Z-VAD.fmk, upon overexpression of the viral caspase inhibitor CrmA and following the RNAi-mediated depletion of caspase-8), and increased cytosolic Ca2+ concentrations (as proven with cytosolic Ca2+ chelators and overexpression of the ER Ca2+ pump SERCA). Moreover, Hyp-PDT induced the translocation of CRT at the cell surface irrespective of retrograde transport (as demonstrated with the microtubular poison nocodazole) and lipid rafts (as demonstrated with the cholesterol-depleting agent methyl-β-cyclodextrine). Of note, ATP secretion in response to Hyp-PDT depended on the ER-to-Golgi anterograde transport, PI3K and PERK activity (presumably due to their role in the regulation of secretory pathways), but did not require BAX and BAK (Garg et al, 2012). Since PERK can stimulate autophagy in the context of ER stress (Kroemer et al, 2010), it is tempting to speculate that autophagy is involved in Hyp-PDT-elicited ATP secretion, as this appears to be to the case during anthracycline-induced ICD (Michaud et al, 2011). Altogether, the intriguing report by Garg et al (2012) demonstrates that the stress signalling pathways leading to ICD depend—at least in part—on the initiating stimulus (Figure 1). Speculatively, this points to the coexistence of a ‘core' ICD signalling pathway (which would be common to several, if not all, ICD inducers) with ‘private' molecular cascades (which would be activated in a stimulus-dependent fashion). Irrespective of these details, the work by Garg et al (2012) further underscores the importance of anticancer immune responses elicited by established and experimental therapies. Figure 1 Molecular mechanisms of immunogenic cell death (ICD). At least three processes underlie the immunogenicity of cell death: the pre-apoptotic exposure of calreticulin (CRT) at the cell surface, the secretion of ATP, and the post-apoptotic release of HMGB1. ...

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Lorenzo Galluzzi1, Lorenzo Galluzzi2, Lorenzo Galluzzi3, Ilio Vitale3, Ilio Vitale1, Ilio Vitale2, Laura Senovilla3, Laura Senovilla1, Laura Senovilla2, Ken A. Olaussen1, Ken A. Olaussen3, Ken A. Olaussen2, Guillaume Pinna4, Guillaume Pinna1, Tobias Eisenberg5, Aicha Goubar1, Aicha Goubar2, Aicha Goubar3, Isabelle Martins2, Isabelle Martins3, Isabelle Martins1, Judith Michels3, Judith Michels2, Judith Michels1, Gueorgui Kratassiouk4, Gueorgui Kratassiouk1, Didac Carmona-Gutierrez5, Marie Scoazec2, Erika Vacchelli1, Erika Vacchelli3, Erika Vacchelli2, Frédéric Schlemmer2, Frédéric Schlemmer1, Frédéric Schlemmer3, Oliver Kepp1, Oliver Kepp3, Oliver Kepp2, Shensi Shen1, Shensi Shen3, Shensi Shen2, Maximilien Tailler1, Maximilien Tailler2, Maximilien Tailler3, Mireia Niso-Santano1, Mireia Niso-Santano3, Mireia Niso-Santano2, Eugenia Morselli1, Eugenia Morselli3, Eugenia Morselli2, Alfredo Criollo2, Alfredo Criollo3, Alfredo Criollo1, Sandy Adjemian2, Sandy Adjemian1, Sandy Adjemian3, Mohamed Jemaà3, Mohamed Jemaà1, Mohamed Jemaà2, Kariman Chaba2, Kariman Chaba3, Claire Pailleret1, Claire Pailleret3, Claire Pailleret2, Mickaël Michaud3, Mickaël Michaud1, Mickaël Michaud2, Federico Pietrocola1, Federico Pietrocola3, Federico Pietrocola2, Nicolas Tajeddine1, Nicolas Tajeddine3, Nicolas Tajeddine2, Thibault De La Motte Rouge, Natalia Araujo4, Natalia Araujo1, Nadya Morozova1, Nadya Morozova4, Thomas Robert2, Hugues Ripoche2, Hugues Ripoche4, Frédéric Commo2, Frédéric Commo3, Frédéric Commo1, Benjamin Besse2, Pierre Validire, Pierre Fouret6, Pierre Fouret3, Angélique Robin1, Angélique Robin2, Angélique Robin3, Nicolas Dorvault3, Nicolas Dorvault1, Nicolas Dorvault2, Philippe Girard, Sebastien Gouy2, Patricia Pautier2, Nora Jägemann, Ann Christin Nickel7, Sabrina Marsili, Caroline Paccard8, Caroline Paccard9, Caroline Paccard3, Nicolas Servant3, Nicolas Servant8, Nicolas Servant9, Philippe Hupé, Carmen Behrens10, Parviz Behnam-Motlagh11, Kimitoshi Kohno12, Isabelle Cremer, Diane Damotte13, Marco Alifano, Øivind Midttun, Per Magne Ueland14, Vladimir Lazar2, Philippe Dessen2, Philippe Dessen3, Hans Zischka, Etienne Chatelut, Maria Castedo2, Maria Castedo3, Maria Castedo1, Frank Madeo5, Emmanuel Barillot3, Emmanuel Barillot9, Emmanuel Barillot8, Juergen Thomale7, Ignacio I. Wistuba10, Catherine Sautès-Fridman13, Catherine Sautès-Fridman3, Laurence Zitvogel3, Laurence Zitvogel2, Jean-Charles Soria, Annick Harel-Bellan1, Annick Harel-Bellan4, Guido Kroemer 
TL;DR: Results indicate that PDXK expression levels constitute a biomarker for risk stratification among patients with NSCLC, in line with a general role of vitamin B6 in stress responses.

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TL;DR: It is concluded that a subset of BCL‐2 family members participates in a new UPR‐regulatory network, thus assuming apoptosis‐unrelated functions.
Abstract: Adaptation to endoplasmic reticulum (ER) stress depends on the activation of the unfolded protein response (UPR) stress sensor inositol-requiring enzyme 1α (IRE1α), which functions as an endoribonuclease that splices the mRNA of the transcription factor XBP-1 (X-box-binding protein-1). Through a global proteomic approach we identified the BCL-2 family member PUMA as a novel IRE1α interactor. Immun oprecipitation experiments confirmed this interaction and further detected the association of IRE1α with BIM, another BH3-only protein. BIM and PUMA double-knockout cells failed to maintain sustained XBP-1 mRNA splicing after prolonged ER stress, resulting in early inactivation. Mutation in the BH3 domain of BIM abrogated the physical interaction with IRE1α, inhibiting its effects on XBP-1 mRNA splicing. Unexpectedly, this regulation required BCL-2 and was antagonized by BAD or the BH3 domain mimetic ABT-737. The modulation of IRE1α RNAse activity by BH3-only proteins was recapitulated in a cell-free system suggesting a direct regulation. Moreover, BH3-only proteins controlled XBP-1 mRNA splicing in vivo and affected the ER stress-regulated secretion of antibodies by primary B cells. We conclude that a subset of BCL-2 family members participates in a new UPR-regulatory network, thus assuming apoptosis-unrelated functions.

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TL;DR: Novel aspects of γδ T cell function during the course of anticancer therapies, as well as new avenues for their clinical implementation are discussed.

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TL;DR: The latest developments in this area of clinical research are summarized, focusing on high impact studies that have been published during the last 13 mo and clinical trials launched in the same period to investigate which cytokines can be employed as safe and efficient immunostimulatory interventions against cancer.
Abstract: During the last two decades, a number of approaches for the activation of the immune system against cancer has been developed. These include highly specific interventions, such as monoclonal antibodies, vaccines and cell-based therapies, as well as relatively unselective strategies, such as the systemic administration of adjuvants and immunomodulatory cytokines. Cytokines constitute a huge group of proteins that, taken together, regulate not only virtually all the aspects of innate and cognate immunity, but also several other cellular and organismal functions. Cytokines operate via specific transmembrane receptors that are expressed on the plasma membrane of target cells and, depending on multiple variables, can engage autocrine, paracrine or endocrine signaling pathways. The most appropriate term for defining the cytokine network is “pleiotropic”: cytokines are produced by - and operate on - multiple, often overlapping, cell types, triggering context-depend biological outcomes as diverse as cell proliferation, chemotaxis, differentiation, inflammation, elimination of pathogens and cell death. Moreover, cytokines often induce the release of additional cytokines, thereby engaging self-amplificatory or self-inhibitory signaling cascades. In this Trial Watch, we will summarize the biological properties of cytokines and discuss the progress of ongoing clinical studies evaluating their safety and efficacy as immunomodulatory agents against cancer.

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TL;DR: The unconventional roles of the apoptotic core machinery from a functional perspective are summarized and their pathophysiological implications are discussed.
Abstract: During the past two decades, apoptotic cell death has been the subject of an intense wave of investigation, leading to the discovery of multiple gene products that govern both its induction and execution. In parallel, it has progressively become evident that most, if not all, proteins that had initially been discovered for their essential role in apoptosis also mediate a wide range of non-apoptotic functions. On the one hand, apoptotic regulators and executioners are involved in non-lethal physiological processes as diverse as cell cycle progression, differentiation, metabolism, autophagy and inflammation. On the other hand, pro-apoptotic proteins can control other modalities of programmed cell death, in particular regulated necrosis. In this review, we summarize the unconventional roles of the apoptotic core machinery from a functional perspective and discuss their pathophysiological implications.

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TL;DR: It appears that, at least in some instances, autophagy is required for NFκB activation, highlighting an intimate crosstalk between these two stress response signaling pathways.
Abstract: It is well-established that the activation of the inhibitor of NFκB (IκBα) kinase (IKK) complex is required for autophagy induction by multiple stimuli. Here, we show that in autophagy-competent mo...

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TL;DR: CD4+CD25+Foxp3+ regulatory T cells (Treg) have emerged as a dominant T cell population inhibiting anti-tumor effector T cells, and various drugs originally developed for other therapeutic indications have recently been discovered to inhibit Treg.
Abstract: CD4+CD25+Foxp3+ regulatory T cells (Treg) have emerged as a dominant T cell population inhibiting anti-tumor effector T cells. Initial strategies used for Treg-depletion (cyclophosphamide, anti-CD25 mAb…) also targeted activated T cells, as they share many phenotypic markers. Current, ameliorated approaches to inhibit Treg aim to either block their function or their migration to lymph nodes and the tumor microenvironment. Various drugs originally developed for other therapeutic indications (anti-angiogenic molecules, tyrosine kinase inhibitors,etc) have recently been discovered to inhibit Treg. These approaches are expected to be rapidly translated to clinical applications for therapeutic use in combination with immunomodulators.

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TL;DR: It is shown that IL-18 converts a subset of Kit(-) (CD11b(-)) into Kit(+) natural killer (NK) cells, which accumulate in all lymphoid organs of tumor bearers and mediate immunoablative functions.
Abstract: During cancer development, a number of regulatory cell subsets and immunosuppressive cytokines subvert adaptive immune responses. Although it has been shown that tumor-derived interleukin (IL)-18 participates in the PD-1–dependent tumor progression in NK cell–controlled cancers, the mechanistic cues underlying this immunosuppression remain unknown. Here, we show that IL-18 converts a subset of Kit− (CD11b−) into Kit+ natural killer (NK) cells, which accumulate in all lymphoid organs of tumor bearers and mediate immunoablative functions. Kit+ NK cells overexpressed B7-H1/PD-L1, a ligand for PD-1. The adoptive transfer of Kit+ NK cells promoted tumor growth in two pulmonary metastases tumor models and significantly reduced the dendritic and NK cell pools residing in lymphoid organs in a B7-H1–dependent manner. Neutralization of IL-18 by RNA interference in tumors or systemically by IL-18–binding protein dramatically reduced the accumulation of Kit+CD11b− NK cells in tumor bearers. Together, our findings show that IL-18 produced by tumor cells elicits Kit+CD11b− NK cells endowed with B7-H1–dependent immunoablative functions in mice. Cancer Res; 72(11); 2757–67. ©2012 AACR.