Most (if not all) tumors emerge and progress under a strong evolutionary pressure imposed by trophic, metabolic, immunological, and therapeutic factors. The relative impact of these factors on tumor ...evolution changes over space and time, ultimately favoring the establishment of a neoplastic microenvironment that exhibits considerable genetic, phenotypic, and behavioral heterogeneity in all its components. Here, we discuss the main sources of intratumoral heterogeneity and its impact on the natural history of the disease, including sensitivity to treatment, as we delineate potential strategies to target such a detrimental feature of aggressive malignancies.
Full text
Available for:
GEOZS, IJS, IMTLJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK, ZAGLJ
Dying mammalian cells emit numerous signals that interact with the host to dictate the immunological correlates of cellular stress and death. In the absence of reactive antigenic determinants (which ...is generally the case for healthy cells), such signals may drive inflammation but cannot engage adaptive immunity. Conversely, when cells exhibit sufficient antigenicity, as in the case of infected or malignant cells, their death can culminate with adaptive immune responses that are executed by cytotoxic T lymphocytes and elicit immunological memory. Suggesting a key role for immunogenic cell death (ICD) in immunosurveillance, both pathogens and cancer cells evolved strategies to prevent the recognition of cell death as immunogenic. Intriguingly, normal cells succumbing to conditions that promote the formation of post-translational neoantigens (for example, oxidative stress) can also drive at least some degree of antigen-specific immunity, pointing to a novel implication of ICD in the etiology of non-infectious, non-malignant disorders linked to autoreactivity.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Autophagy contributes to the maintenance of intracellular homeostasis in most cells of cardiovascular origin, including cardiomyocytes, endothelial cells, and arterial smooth muscle cells. Mitophagy ...is an autophagic response that specifically targets damaged, and hence potentially cytotoxic, mitochondria. As these organelles occupy a critical position in the bioenergetics of the cardiovascular system, mitophagy is particularly important for cardiovascular homeostasis in health and disease. Consistent with this notion, genetic defects in autophagy or mitophagy have been shown to exacerbate the propensity of laboratory animals to spontaneously develop cardiodegenerative disorders. Moreover, pharmacological or genetic maneuvers that alter the autophagic or mitophagic flux have been shown to influence disease outcome in rodent models of several cardiovascular conditions, such as myocardial infarction, various types of cardiomyopathy, and atherosclerosis. In this review, we discuss the intimate connection between autophagy, mitophagy, and cardiovascular disorders.
Chemotherapy, radiation therapy, as well as targeted anticancer agents can induce clinically relevant tumor-targeting immune responses, which critically rely on the antigenicity of malignant cells ...and their capacity to generate adjuvant signals. In particular, immunogenic cell death (ICD) is accompanied by the exposure and release of numerous damage-associated molecular patterns (DAMPs), which altogether confer a robust adjuvanticity to dying cancer cells, as they favor the recruitment and activation of antigen-presenting cells. ICD-associated DAMPs include surface-exposed calreticulin (CALR) as well as secreted ATP, annexin A1 (ANXA1), type I interferon, and high-mobility group box 1 (HMGB1). Additional hallmarks of ICD encompass the phosphorylation of eukaryotic translation initiation factor 2 subunit-α (EIF2S1, better known as eIF2α), the activation of autophagy, and a global arrest in transcription and translation. Here, we outline methodological approaches for measuring ICD markers in vitro and ex vivo for the discovery of next-generation antineoplastic agents, the development of personalized anticancer regimens, and the identification of optimal therapeutic combinations for the clinical management of cancer.
Summary Inflammation can be either beneficial or detrimental to the liver, depending on multiple factors. Mild (i.e., limited in intensity and destined to resolve) inflammatory responses have indeed ...been shown to exert consistent hepatoprotective effects, contributing to tissue repair and promoting the re-establishment of homeostasis. Conversely, excessive (i.e., disproportionate in intensity and permanent) inflammation may induce a massive loss of hepatocytes and hence exacerbate the severity of various hepatic conditions, including ischemia-reperfusion injury, systemic metabolic alterations (e.g., obesity, diabetes, non-alcoholic fatty liver disorders), alcoholic hepatitis, intoxication by xenobiotics and infection, de facto being associated with irreversible liver damage, fibrosis, and carcinogenesis. Both liver-resident cells (e.g., Kupffer cells, hepatic stellate cells, sinusoidal endothelial cells) and cells that are recruited in response to injury (e.g., monocytes, macrophages, dendritic cells, natural killer cells) emit pro-inflammatory signals including – but not limited to – cytokines, chemokines, lipid messengers, and reactive oxygen species that contribute to the apoptotic or necrotic demise of hepatocytes. In turn, dying hepatocytes release damage-associated molecular patterns that-upon binding to evolutionary conserved pattern recognition receptors-activate cells of the innate immune system to further stimulate inflammatory responses, hence establishing a highly hepatotoxic feedforward cycle of inflammation and cell death. In this review, we discuss the cellular and molecular mechanisms that account for the most deleterious effect of hepatic inflammation at the cellular level, that is, the initiation of a massive cell death response among hepatocytes.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Tumor-associated macrophages (TAMs) constitute a plastic and heterogeneous cell population of the tumor microenvironment (TME) that can account for up to 50% of some solid neoplasms. Most often, TAMs ...support disease progression and resistance to therapy by providing malignant cells with trophic and nutritional support. However, TAMs can mediate antineoplastic effects, especially in response to pharmacological agents that boost their phagocytic and oxidative functions. Thus, TAMs and their impact on the overall metabolic profile of the TME have a major influence on tumor progression and resistance to therapy, de facto constituting promising targets for the development of novel anticancer agents. Here, we discuss the metabolic circuitries whereby TAMs condition the TME to support tumor growth and how such pathways can be therapeutically targeted.
Vitale et al. discuss the metabolic circuitries whereby tumor-associated macrophages condition their microenvironment to support the cancer growth, metastatic dissemination and resistance to treatment, and how such pathways can be therapeutically targeted.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Conventional chemotherapeutics have been developed into clinically useful agents based on their ability to preferentially kill malignant cells, generally owing to their elevated proliferation rate. ...Nonetheless, the clinical activity of various chemotherapies is now known to involve the stimulation of anticancer immunity either by initiating the release of immunostimulatory molecules from dying cancer cells or by mediating off-target effects on immune cell populations. Understanding the precise immunological mechanisms that underlie the efficacy of chemotherapy has the potential not only to enable the identification of superior biomarkers of response but also to accelerate the development of synergistic combination regimens that enhance the clinical effectiveness of immune checkpoint inhibitors (ICIs) relative to their effectiveness as monotherapies. Indeed, accumulating evidence supports the clinical value of combining appropriately dosed chemotherapies with ICIs. In this Review, we discuss preclinical and clinical data on the immunostimulatory effects of conventional chemotherapeutics in the context of ICI-based immunotherapy.
Full text
Available for:
FZAB, GEOZS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
8.
Calreticulin and cancer Fucikova, Jitka; Spisek, Radek; Kroemer, Guido ...
Cell research,
01/2021, Volume:
31, Issue:
1
Journal Article
Peer reviewed
Open access
Calreticulin (CALR) is an endoplasmic reticulum (ER)-resident protein involved in a spectrum of cellular processes. In healthy cells, CALR operates as a chaperone and Ca
buffer to assist correct ...protein folding within the ER. Besides favoring the maintenance of cellular proteostasis, these cell-intrinsic CALR functions support Ca
-dependent processes, such as adhesion and integrin signaling, and ensure normal antigen presentation on MHC Class I molecules. Moreover, cancer cells succumbing to immunogenic cell death (ICD) expose CALR on their surface, which promotes the uptake of cell corpses by professional phagocytes and ultimately supports the initiation of anticancer immunity. Thus, loss-of-function CALR mutations promote oncogenesis not only as they impair cellular homeostasis in healthy cells, but also as they compromise natural and therapy-driven immunosurveillance. However, the prognostic impact of total or membrane-exposed CALR levels appears to vary considerably with cancer type. For instance, while genetic CALR defects promote pre-neoplastic myeloproliferation, patients with myeloproliferative neoplasms bearing CALR mutations often experience improved overall survival as compared to patients bearing wild-type CALR. Here, we discuss the context-dependent impact of CALR on malignant transformation, tumor progression and response to cancer therapy.
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
It has recently become clear that the tumour microenvironment, and in particular the immune system, has a crucial role in modulating tumour progression and response to therapy. Indicators of an ...ongoing immune response, such as the composition of the intratumoural immune infiltrate, as well as polymorphisms in genes encoding immune modulators, have been correlated with therapeutic outcome. Moreover, several anticancer agents--including classical chemotherapeutics and targeted compounds--stimulate tumour-specific immune responses either by inducing the immunogenic death of tumour cells or by engaging immune effector mechanisms. Here, we discuss the molecular and cellular circuitries whereby cytotoxic agents can activate the immune system against cancer, and their therapeutic implications.
Full text
Available for:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK