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Mammalian cells responding to specific perturbations of homeostasis can undergo a regulated variant of cell death that elicits adaptive immune responses. As immunogenic cell death (ICD) can only occur in a precise cellular and organismal context, it should be conceptually differentiated from instances of immunostimulation or inflammatory responses that do not mechanistically depend on cellular demise. Here, we critically discuss key conceptual and mechanistic aspects of ICD and its implications for cancer (immuno)therapy. [ABSTRACT FROM AUTHOR]

When cellular damage can be efficiently repaired and/or microenvironmental perturbations are limited in intensity and duration, cells can recover physiological functions in the context of re-established homeostasis [[2]]. These mechanisms encompass, but are not limited to: the DNA damage response [[4]], the unfolded protein response [[5]], and autophagy [[6]]. On the contrary, when damage is beyond repair and/or stressful stimuli are excessively intense or prolonged, the same pathways that initially attempt to restore physiological homeostasis instead engage signaling modules that actively promote cellular demise, a process that has been dubbed regulated cell death (RCD) [[1]]. Eukaryotic cells exposed to extreme perturbations of homeostasis, which are relatively rare in nature, succumb to the unregulated and virtually immediate physical breakdown of their components, a process that has been dubbed accidental cell death (ACD) [[1]]. [Extracted from the article]

Newly formed malignant cells must escape immunosurveillance to generate progressing neoplastic lesions of clinical relevance. Recent data indicate that the immunogenicity of nascent cancer cells, at least in some settings, is dictated by inherent epigenetic mechanisms rather than by immunoediting and the consequent Darwinian selection of poorly immunogenic phenotypes. [ABSTRACT FROM AUTHOR]

Mitochondrial outer membrane permeabilization (MOMP) is crucial for the cytosolic accumulation of mitochondrial DNA (mtDNA) species that are required to jumpstart innate and adaptive immunity. Recent data reported by Ghosh et al. suggest that tumor protein p53 regulates MOMP-dependent type I interferon (IFN) production, not only via MOMP-promoting effects, but also by directing mtDNA-degrading exonucleases to proteasomal processing. [ABSTRACT FROM AUTHOR]

Endoplasmic reticulum stress can stimulate calreticulin (CALR) presentation on the cell surface, promoting the phagocytic uptake of stressed cells by myeloid cells. Recent findings from Wattrus et al. demonstrate that zebrafish and mouse embryonic macrophages engulf CALR-exposing nascent hematopoietic stem cells to ensure the selective survival of stem cells apt for adult hematopoiesis. [ABSTRACT FROM AUTHOR]

Radiation therapy (RT) and cyclin-dependent kinase 4/6 (CDK4/6) inhibitors mediate poorly overlapping cytostatic and immunostimulatory effects, suggesting that combinatorial regimens may enable supra- additive tumor control. Our preclinical findings demonstrate that administration schedule stands out as a major determinant of efficacy when RT and CDK4/6 inhibitors are combined for breast cancer therapy. [ABSTRACT FROM AUTHOR]

Type I interferon (IFN) release by irradiated cancer cells is paramount for radiation therapy to elicit anticancer immunity. Our findings demonstrate that mitochondrial outer membrane permeabilization (MOMP) triggered by RT enables exposure of mitochondrial DNA to the cytosol, hence setting off CGAS-driven type I IFN synthesis. These data point to the existence of a therapeutically actionable mitochondrial checkpoint that restricts innate immune signaling in irradiated cancer cells. [ABSTRACT FROM AUTHOR]

Indoleamine 2,3-dioxygenase 1 (IDO1) catalyzes the first, rate-limiting step of the so-called "kynurenine pathway", which converts the essential amino acid L-tryptophan (Trp) into the immunosuppressive metabolite L-kynurenine (Kyn). While expressed constitutively by some tissues, IDO1 can also be induced in specific subsets of antigen-presenting cells that ultimately favor the establishment of immune tolerance to tumor antigens. At least in part, the immunomodulatory functions of IDO1 can be explained by depletion of Trp and accumulation of Kyn and its derivatives. In animal tumor models, genetic or pharmacological IDO1 inhibition can cause the (re)activation of anticancer immune responses. Similarly, neoplasms expressing high levels of IDO1 may elude anticancer immunosurveillance. Therefore, IDO1 inhibitors represent promising therapeutic candidates for cancer therapy, and some of them have already entered clinical evaluation. Here, we summarize preclinical and clinical studies testing IDO1-targeting interventions for oncologic indications. [ABSTRACT FROM AUTHOR]

Toll-like receptor 3 (TLR3) is a pattern recognition receptor that senses exogenous (viral) as well as endogenous (mammalian) double-stranded RNA in endosomes. On activation, TLR3 initiates a signal transduction pathway that culminates with the secretion of pro-inflammatory cytokines including type I interferon (IFN). The latter is essential not only for innate immune responses to infection but also for the initiation of antigen-specific immunity against viruses and malignant cells. These aspects of TLR3 biology have supported the development of various agonists for use as stand-alone agents or combined with other therapeutic modalities in cancer patients. Here, we review recent preclinical and clinical advances in the development of TLR3 agonists for oncological disorders. cDC, conventional dendritic cell; CMT, cytokine modulating treatment; CRC, colorectal carcinoma; CTL, cytotoxic T lymphocyte; DC, dendritic cell; dsRNA, double-stranded RNA; FLT3LG, fms-related receptor tyrosine kinase 3 ligand; HNSCC, head and neck squamous cell carcinoma; IFN, interferon; IL, interleukin; ISV, in situ vaccine; MUC1, mucin 1, cell surface associated; PD-1, programmed cell death 1; PD-L1, programmed death-ligand 1; polyA:U, polyadenylic:polyuridylic acid; polyI:C, polyriboinosinic:polyribocytidylic acid; TLR, Toll-like receptor [ABSTRACT FROM AUTHOR]

Deregulated WNT signaling has been shown to favor malignant transformation, tumor progression, and resistance to conventional cancer therapy in a variety of preclinical and clinical settings. Accumulating evidence suggests that aberrant WNT signaling may also subvert cancer immunosurveillance, hence promoting immunoevasion and resistance to multiple immunotherapeutics, including immune checkpoint blockers. Here, we discuss the molecular and cellular mechanisms through which WNT signaling influences cancer immunosurveillance and present potential therapeutic avenues to harness currently available WNT modulators for cancer immunotherapy. Highlights Canonical WNT signaling plays a central role in embryogenesis, tissue homeostasis, and wound repair. Deregulated WNT signaling is involved in virtually all stages of oncogenesis. Impaired anticancer immunity as a result of aberrant WNT signaling is emerging as a key contributor to tumor progression and resistance to treatment. Activation of canonical WNT signaling hampers T cell-mediated anticancer immune responses by multiple mechanisms including immune exclusion. [ABSTRACT FROM AUTHOR]

Carbohydrate-rich diets have been consistently associated with detrimental effects for human health, including diabetes and obesity. Moreover, high glucose levels appear to mediate immunosuppressive effects in preclinical tumor models. Recent data from Ferrere and colleagues point to the intriguing possibility that carbotoxicity may originate from the abolition of ketosis. [ABSTRACT FROM AUTHOR]

Unscheduled tetraploidy is a metastable state that rapidly evolves into aneuploidy. Recent findings reported by Gemble et al. demonstrate that freshly formed tetraploid cells fail to accumulate the required amounts of DNA replication factors during the first G 1 phase after whole-genome duplication (WGD), culminating in genetic instability in the subsequent S phase and extensive karyotypic alterations. [ABSTRACT FROM AUTHOR]

Although somatic KRAS mutations are common in human tumors, no inhibitor of mutant KRAS was clinically available until recently. Canon and colleagues describe the ability of a clinically available KRASG12C inhibitor to drive immunogenic cancer cell death, thus constituting a promising combinatorial partner for immune checkpoint blockers. [ABSTRACT FROM AUTHOR]

Over the past two decades, the molecular machinery that underlies autophagic responses has been characterized with ever increasing precision in multiple model organisms. Moreover, it has become clear that autophagy and autophagy-related processes have profound implications for human pathophysiology. However, considerable confusion persists about the use of appropriate terms to indicate specific types of autophagy and some components of the autophagy machinery, which may have detrimental effects on the expansion of the field. Driven by the overt recognition of such a potential obstacle, a panel of leading experts in the field attempts here to define several autophagy-related terms based on specific biochemical features. The ultimate objective of this collaborative exchange is to formulate recommendations that facilitate the dissemination of knowledge within and outside the field of autophagy research. [ABSTRACT FROM AUTHOR]

Several metabolic alterations accumulate over time along with a reduction in biological fitness, suggesting the existence of a “metabolic clock” that controls aging. Multiple inborn defects in metabolic circuitries accelerate aging, whereas genetic loci linked to exceptional longevity influence metabolism. Each of the nine hallmarks of aging is connected to undesirable metabolic alterations. The main features of the “westernized” lifestyle, including hypercaloric nutrition and sedentariness, can accelerate aging as they have detrimental metabolic consequences. Conversely, lifespan-extending maneuvers including caloric restriction impose beneficial pleiotropic effects on metabolism. The introduction of strategies that promote metabolic fitness may extend healthspan in humans. [ABSTRACT FROM AUTHOR]

Glucocorticoids (GCs) are widely used for the management of disease- or therapy-related complications in cancer patients. Recent data indicate that activation of GC receptors (GRs) precipitates breast cancer progression by favoring metastatic dissemination and cell survival at distant sites. These findings call for the re-evaluation of GC usage in patients with cancer. [ABSTRACT FROM AUTHOR]

Cytotoxic T lymphocytes recognize and kill cancer cells when the latter present antigenic epitopes complexed with MHC class I molecules on their surface. In a recent Science paper, Mangalhara et al. show that alterations of the mitochondrial electron flow upregulate multiple factors involved in antigen presentation via a succinate-dependent epigenetic mechanism. Cytotoxic T lymphocytes recognize and kill cancer cells when the latter present antigenic epitopes complexed with MHC class I molecules on their surface. In a Science paper, Mangalhara et al. show that alterations of the mitochondrial electron flow upregulate multiple factors involved in antigen presentation via a succinate-dependent epigenetic mechanism. [ABSTRACT FROM AUTHOR]

Eukaryotic cells react to potentially dangerous perturbations of the intracellular or extracellular microenvironment by activating rapid (transcription-independent) mechanisms that attempt to restore homeostasis. If such perturbations persist, cells may still try to cope with stress by activating delayed and robust (transcription-dependent) adaptive systems, or they may actively engage in cellular suicide. This regulated form of cell death can manifest with various morphological, biochemical and immunological correlates, and constitutes an ultimate attempt of stressed cells to maintain organismal homeostasis. Here, we dissect the general organization of adaptive cellular responses to stress, their intimate connection with regulated cell death, and how the latter operates for the preservation of organismal homeostasis. [ABSTRACT FROM AUTHOR]

Some forms of regulated cell death, such as apoptosis, are precipitated by the activation of cysteine proteases of the caspase family, including caspase 8, 9, and 3. Other caspases, such as caspase 1 and 4, are well known for their pro-inflammatory functions but regulate cell death in a limited number of pathophysiological settings. Accumulating evidence suggests that the most conserved function of mammalian caspases is not to control cell death sensu stricto, but to regulate inflammatory and immune reactions to dying cells and infectious challenges. Here, we review the molecular and cellular mechanisms though which mammalian caspases connect cell-death signaling to the maintenance of organismal homeostasis. [ABSTRACT FROM AUTHOR]

The tremendous clinical success of checkpoint blockers illustrates the potential of reestablishing latent immunosurveillance for cancer therapy. Although largely neglected in the clinical practice, accumulating evidence indicates that the efficacy of conventional and targeted anticancer agents does not only involve direct cytostatic/cytotoxic effects, but also relies on the (re)activation of tumor-targeting immune responses. Chemotherapy can promote such responses by increasing the immunogenicity of malignant cells, or by inhibiting immunosuppressive circuitries that are established by developing neoplasms. These immunological “side” effects of chemotherapy are desirable, and their in-depth comprehension will facilitate the design of novel combinatorial regimens with improved clinical efficacy. [ABSTRACT FROM AUTHOR]

Autophagy constitutes a prominent mechanism through which eukaryotic cells preserve homeostasis in baseline conditions and in response to perturbations of the intracellular or extracellular microenvironment. Autophagic responses can be relatively non-selective or target a specific subcellular compartment. At least in part, this depends on the balance between the availability of autophagic substrates (“offer”) and the cellular need of autophagic products or functions for adaptation (“demand”). Irrespective of cargo specificity, adaptive autophagy relies on a panel of sensors that detect potentially dangerous cues and convert them into signals that are ultimately relayed to the autophagic machinery. Here, we summarize the molecular systems through which specific subcellular compartments—including the nucleus, mitochondria, plasma membrane, reticular apparatus, and cytosol—convert homeostatic perturbations into an increased offer of autophagic substrates or an accrued cellular demand for autophagic products or functions. [ABSTRACT FROM AUTHOR]

Large BAX/BAK pores that form during apoptosis enable mitochondrial nucleoids to access the cytosol, potentially leading to inflammatory signaling via CGAS. Under physiological conditions, however, BAX/BAK-dependent caspase activation rapidly dismantles dying cells to prevent inflammatory responses. BAX and BAK operate at the interface between apoptotic signaling and innate immunity control. [ABSTRACT FROM AUTHOR]

Two recent genomic studies suggest that a large fraction of human tumors evolves in the presence of limited negative selection against somatic mutations. In this context, specific genetic defects enable the establishment of a hypermutant state that may constitute a target for immunotherapeutic interventions. [ABSTRACT FROM AUTHOR]

Demaria and colleagues have recently identified three prime repair exonuclease 1 (TREX1) as a key determinant for the limited immunogenicity of cancer cells responding to single high-dose radiation. TREX1 stands out as a promising target for the development of novel strategies to boost anticancer immune responses driven by radiation therapy (RT). [ABSTRACT FROM AUTHOR]

Two resource articles recently published in Cell demonstrate that the elevated phenotypic complexity of the immune infiltrate in human lung adenocarcinomas and renal cell carcinomas can be reliably dissected with mass cytometry. These findings may pave the way to a new era of precision cancer immunotherapy. [ABSTRACT FROM AUTHOR]

Type I interferons (IFNs) are known for their key role in antiviral immune responses. In this Review, we discuss accumulating evidence indicating that type I IFNs produced by malignant cells or tumour-infiltrating dendritic cells also control the autocrine or paracrine circuits that underlie cancer immunosurveillance. Many conventional chemotherapeutics, targeted anticancer agents, immunological adjuvants and oncolytic viruses are only fully efficient in the presence of intact type I IFN signalling. Moreover, the intratumoural expression levels of type I IFNs or of IFN-stimulated genes correlate with favourable disease outcome in several cohorts of patients with cancer. Finally, new anticancer immunotherapies are being developed that are based on recombinant type I IFNs, type I IFN-encoding vectors and type I IFN-expressing cells. [ABSTRACT FROM AUTHOR]

Autophagy plays a key role in the maintenance of cellular homeostasis. In healthy cells, such a homeostatic activity constitutes a robust barrier against malignant transformation. Accordingly, many oncoproteins inhibit, and several oncosuppressor proteins promote, autophagy. Moreover, autophagy is required for optimal anticancer immunosurveillance. In neoplastic cells, however, autophagic responses constitute a means to cope with intracellular and environmental stress, thus favoring tumor progression. This implies that at least in some cases, oncogenesis proceeds along with a temporary inhibition of autophagy or a gain of molecular functions that antagonize its oncosuppressive activity. Here, we discuss the differential impact of autophagy on distinct phases of tumorigenesis and the implications of this concept for the use of autophagy modulators in cancer therapy. [ABSTRACT FROM AUTHOR]

Macroautophagy (herein referred to as autophagy) is an evolutionarily conserved mechanism of adaptation to adverse microenvironmental conditions, including limited nutrient supplies. Several sensors interacting with the autophagic machinery have evolved to detect fluctuations in key metabolic parameters. The signal transduction cascades operating downstream of these sensors are highly interconnected to control a spatially and chronologically coordinated autophagic response that maintains the health and function of individual cells while preserving organismal homeostasis. Here, we discuss the physiological regulation of autophagy by metabolic circuitries, as well as alterations of such control in disease. [ABSTRACT FROM AUTHOR]

It is now clear that apoptosis does not constitute the sole genetically encoded form of cell death. Rather, cells can spontaneously undertake or exogenously be driven into a cell death subroutine that manifests with necrotic features, yet can be inhibited by pharmacological and genetic interventions. As regulated necrosis (RN) plays a major role in both physiological scenarios ( e.g. , embryonic development) and pathological settings ( e.g. , ischemic disorders), consistent efforts have been made throughout the last decade toward the characterization of the molecular mechanisms that underlie this cell death modality. Contrarily to initial beliefs, RN does not invariably result from the activation of a receptor interacting protein kinase 3 (RIPK3)-dependent signaling pathway, but may be ignited by distinct molecular networks. Nowadays, various types of RN have been characterized, including (but not limited to) necroptosis, mitochondrial permeability transition (MPT)-dependent RN and parthanatos. Of note, the inhibition of only one of these modules generally exerts limited cytoprotective effects in vivo , underscoring the degree of interconnectivity that characterizes RN. Here, we review the signaling pathways, pathophysiological relevance and therapeutic implications of the major molecular cascades that underlie RN. [ABSTRACT FROM AUTHOR]

In a majority of pathophysiological settings, cell death is not accidental - it is controlled by a complex molecular apparatus. Such a system operates like a computer: it receives several inputs that inform on the current state of the cell and the extracellular microenvironment, integrates them and generates an output. Thus, depending on a network of signals generated at specific subcellular sites, cells can respond to stress by attemptinwg to recover homeostasis or by activating molecular cascades that lead to cell death by apoptosis or necrosis. Here, we discuss the mechanisms whereby cellular compartments - including the nucleus, mitochondria, plasma membrane, endoplasmic reticulum, Golgi apparatus, lysosomes, cytoskeleton and cytosol - sense homeostatic perturbations and translate them into a cell-death-initiating signal. [ABSTRACT FROM AUTHOR]

Autophagy not only constitutes a robust barrier against malignant transformation at the cell-intrinsic level, but also contributes to the organismal control of potentially oncogenic cells. Recent data provide molecular insights into the mechanisms whereby oncogene hyperactivation induces autophagy to establish a permanent proliferative arrest commonly known as cellular senescence. [ABSTRACT FROM AUTHOR]

Recent findings demonstrate that transient genetic inhibition of autophagy promotes age-associated pathologies in mice. While autophagy restoration effectively counteracts such disorders, it also exacerbates the incidence of various solid and hematological tumors. These data may cast additional shadows on the clinical potential of autophagy inhibition for cancer therapy. [ABSTRACT FROM AUTHOR]

Calreticulin (CALR) exposure on the cell surface is known to deliver robust pro-phagocytic signals to myeloid cells. In Nature , Sen Santara et al. demonstrate that surface-exposed CALR also operates as an endogenous activator of natural killer (NK) cells. Collectively, these findings suggest that CALR exposure orchestrates multiple facets of innate immunosurveillance. [ABSTRACT FROM AUTHOR]

CTLA4 blockers have limited activity in patients with chemorefractory lung cancer. Recent clinical data demonstrate that radiation therapy combined with CTLA4 blockers enables disease control in a sizeable fraction of these patients, correlating with increased circulating levels of type I interferon and dynamic changes in the peripheral T cell repertoire. [ABSTRACT FROM AUTHOR]

Tumor progression and resistance to treatment are often accompanied by the polarization of malignant cells towards a mesenchymal or poorly differentiated state. Such a transition generates an accrued vulnerability to the induction of ferroptosis, potentially paving the way to novel therapeutic strategies for targeting residual disease in patients with cancer. [ABSTRACT FROM AUTHOR]

Recent findings from a prospective clinical study involving multiregion whole-exome sequencing suggest that driver mutations in cancer-relevant genes including EGFR and TP53 are often clonal and precede whole-genome duplication events in early lung carcinogenesis. This paves an expressway to extensive subclonal diversification, elevated intratumoral heterogeneity, and dismal disease outcome. [ABSTRACT FROM AUTHOR]

Macroautophagy/autophagy is a complex degradation process with a dual role in cell death that is influenced by the cell types that are involved and the stressors they are exposed to. Ferroptosis is an iron-dependent oxidative form of cell death characterized by unrestricted lipid peroxidation in the context of heterogeneous and plastic mechanisms. Recent studies have shed light on the involvement of specific types of autophagy (e.g. ferritinophagy, lipophagy, and clockophagy) in initiating or executing ferroptotic cell death through the selective degradation of anti-injury proteins or organelles. Conversely, other forms of selective autophagy (e.g. reticulophagy and lysophagy) enhance the cellular defense against ferroptotic damage. Dysregulated autophagy-dependent ferroptosis has implications for a diverse range of pathological conditions. This review aims to present an updated definition of autophagy-dependent ferroptosis, discuss influential substrates and receptors, outline experimental methods, and propose guidelines for interpreting the results.Abbreviation: 3-MA:3-methyladenine; 4HNE: 4-hydroxynonenal; ACD: accidentalcell death; ADF: autophagy-dependentferroptosis; ARE: antioxidant response element; BH2:dihydrobiopterin; BH4: tetrahydrobiopterin; BMDMs: bonemarrow-derived macrophages; CMA: chaperone-mediated autophagy; CQ:chloroquine; DAMPs: danger/damage-associated molecular patterns; EMT,epithelial-mesenchymal transition; EPR: electronparamagnetic resonance; ER, endoplasmic reticulum; FRET: Försterresonance energy transfer; GFP: green fluorescent protein;GSH: glutathione;IF: immunofluorescence; IHC: immunohistochemistry; IOP, intraocularpressure; IRI: ischemia-reperfusion injury; LAA: linoleamide alkyne;MDA: malondialdehyde; PGSK: Phen Green™ SK;RCD: regulatedcell death; PUFAs: polyunsaturated fatty acids; RFP: red fluorescentprotein;ROS: reactive oxygen species; TBA: thiobarbituricacid; TBARS: thiobarbituric acid reactive substances; TEM:transmission electron microscopy. [ABSTRACT FROM AUTHOR]

At odds with its nuclear counterpart, extranuclear promyelocytic leukemia constitutively inhibits autophagy, hence limiting cancer progression. These data raise the interesting possibility that some tumor suppressors have become specialized to operate at multiple subcellular compartments for counteracting different aspects of the oncogenic process. [ABSTRACT FROM AUTHOR]

The article discusses the etiological association of cystic fibrosis (CF) transmembrane conductance regulator (CFTR) in unrelated human diseases. Topics discussed include the involvement of CFTR in the pathogenesis of CF, the CFTR expression in mouse models, and the higher incidence of celiac disease (CD) in CF patients.

Somatic gain-of-function mutations in isocitrate dehydrogenase (NADP(+)) 1, cytosolic (IDH1) or isocitrate dehydrogenase (NADP(+)) 2, mitochondrial (IDH2) are bona fide oncogenic drivers of acute myeloid leukemia and glioma because the neomorphic enzymes catalyze the synthesis of R-2-hydroxylutarate (R-2-HG), an oncometabolite with robust epigenetic effects. Recent data indicate that R-2-HG released by malignant cells can accumulate in the extracellular space and be taken up by T lymphocytes, ultimately compromising their capacity to mediate anticancer immune responses. Thus, R-2-HG drives oncogenesis and tumor progression not only as a cancer cell-autonomous epigenetic modifier, but also as an immunosuppressive metabolite. Chemical inhibitors of mutant IDH1 and IDH2, which currently are under clinical evaluation, may therefore mediate dual anticancer effects by targeting cancer cells and, at the same time, relieving R-2-HG-mediated immunosuppression. [ABSTRACT FROM AUTHOR]

Autophagy is quintessential for the maintenance of cellular homeostasis in all eukaryotic cells, explaining why both normal and malignant cells benefit from proficient autophagic responses. Moreover, autophagy is intimately involved in the immunological control of malignant transformation, tumor progression and response to therapy. However, the net effect of autophagy activation or inhibition on the natural growth or therapeutic response of tumors evolving in immunocompetent hosts exhibits a considerable degree of context dependency. Here, we discuss the complex cross-talk between autophagy and immuno-oncology as delineated by genetic and pharmacological approaches in mouse models of cancer. Unlabelled Image [ABSTRACT FROM AUTHOR]

Summary: Cancer cells undergoing immunogenic cell death (ICD) can initiate adaptive immune responses against dead cell‐associated antigens, provided that (1) said antigens are not perfectly covered by central tolerance (antigenicity), (2) cell death occurs along with the emission of immunostimulatory cytokines and damage‐associated molecular patterns (DAMPs) that actively engage immune effector mechanisms (adjuvanticity), and (3) the microenvironment of dying cells is permissive for the initiation of adaptive immunity. Finally, ICD‐driven immune responses can only operate and exert cytotoxic effector functions if the microenvironment of target cancer cells enables immune cell infiltration and activity. Multiple forms of radiation, including non‐ionizing (ultraviolet) and ionizing radiation, elicit bona fide ICD as they increase both the antigenicity and adjuvanticity of dying cancer cells. Here, we review the molecular determinants of ICD as elicited by radiation as we critically discuss strategies to reinforce the immunogenicity of cancer cells succumbing to clinically available radiation strategies. [ABSTRACT FROM AUTHOR]

Summary: Type I interferon (IFN) is a class of proinflammatory cytokines with a dual role on malignant transformation, tumor progression, and response to therapy. On the one hand, robust, acute, and resolving type I IFN responses have been shown to mediate prominent anticancer effects, reflecting not only their direct cytostatic/cytotoxic activity on (at least some) malignant cells, but also their pronounced immunostimulatory functions. In line with this notion, type I IFN signaling has been implicated in the antineoplastic effects of various immunogenic therapeutics, including (but not limited to) immunogenic cell death (ICD)‐inducing agents and immune checkpoint inhibitors (ICIs). On the other hand, weak, indolent, and non‐resolving type I IFN responses have been demonstrated to support tumor progression and resistance to therapy, reflecting the ability of suboptimal type I IFN signaling to mediate cytoprotective activity, promote stemness, favor tolerance to chromosomal instability, and facilitate the establishment of an immunologically exhausted tumor microenvironment. Here, we review fundamental aspects of type I IFN signaling and their context‐dependent impact on malignant transformation, tumor progression, and response to therapy. [ABSTRACT FROM AUTHOR]

In this issue of Molecular Cell , Park et al. (2016) elegantly demonstrate that a partial defect in autophagy supports malignant transformation as it favors the production of genotoxic reactive oxygen species by mitochondria. [ABSTRACT FROM AUTHOR]

While chemotherapy and radiotherapy remain the first-line approaches for the management of most unresectable tumors, immunotherapy has emerged in the past two decades as a game-changing treatment, notably with the clinical success of immune checkpoint inhibitors. Immunotherapies aim at (re) activating anticancer immune responses which occur in two main steps: (1) the activation and expansion of tumor-specific T cells following cross-presentation of tumor antigens by specialized myeloid cells (priming phase); and (2) the immunological clearance of malignant cells by these antitumor T lymphocytes (effector phase). Therapeutic vaccines, adjuvants, monoclonal antibodies, cytokines, immunogenic cell death-inducing agents including oncolytic viruses, anthracycline-based chemotherapy and radio-therapy, as well as adoptive cell transfer, all act at different levels of this cascade to (re)instate cancer immunosurveillance. Intratumoral delivery of these immunotherapeutics is being tested in clinical trials to promote superior antitumor immune activity in the context of limited systemic toxicity. [ABSTRACT FROM AUTHOR]

Cancer stem cells (CSCs) are known for their superior tumor-initiating and tumor-repopulating potential, partly reflecting their pronounced ability to evade immune recognition. Liu and colleagues recently identified a new aldehyde dehydrogenase (ALDH)-dependent mechanism whereby triple-negative breast CSCs evade immunosurveillance upon recruitment of myeloid-derived suppressor cells. [ABSTRACT FROM AUTHOR]