Effective clinical cancer immunotherapies, such as administration of the cytokine IL-2, adoptive cell transfer (ACT) and the recent success of blockade of the checkpoint modulators CTLA-4 and PD-1, ...have been developed without clear identification of the immunogenic targets expressed by human cancers in vivo. Immunotherapy of patients with cancer through the use of ACT with autologous lymphocytes has provided an opportunity to directly investigate the antigen recognition of lymphocytes that mediate cancer regression in humans. High-throughput immunological testing of such lymphocytes in combination with improvements in deep sequencing of the autologous cancer have provided new insight into the molecular characterization and incidence of anti-tumor lymphocytes present in patients with cancer. Here we highlight evidence suggesting that T cells that target tumor neoantigens arising from cancer mutations are the main mediators of many effective cancer immunotherapies in humans.
Extracellular vesicles, including exosomes, are small membrane vesicles derived from multivesicular bodies or from the plasma membrane. Most, if not all, cell types release extracellular vesicles, ...which then enter the bodily fluids. These vesicles contain a subset of proteins, lipids and nucleic acids that are derived from the parent cell. It is thought that extracellular vesicles have important roles in intercellular communication, both locally and systemically, as they transfer their contents, including proteins, lipids and RNAs, between cells. Extracellular vesicles are involved in numerous physiological processes, and vesicles from both non-immune and immune cells have important roles in immune regulation. Moreover, extracellular vesicle-based therapeutics are being developed and clinically tested for the treatment of inflammatory diseases, autoimmune disorders and cancer. Given the tremendous therapeutic potential of extracellular vesicles, this Review focuses on their role in modulating immune responses, as well as their potential therapeutic applications.
The Clinical Potential of Senolytic Drugs Kirkland, James L.; Tchkonia, Tamara; Zhu, Yi ...
Journal of the American Geriatrics Society,
October 2017, Letnik:
65, Številka:
10
Journal Article
Recenzirano
Odprti dostop
Senolytic drugs are agents that selectively induce apoptosis of senescent cells. These cells accumulate in many tissues with aging and at sites of pathology in multiple chronic diseases. In studies ...in animals, targeting senescent cells using genetic or pharmacological approaches delays, prevents, or alleviates multiple age‐related phenotypes, chronic diseases, geriatric syndromes, and loss of physiological resilience. Among the chronic conditions successfully treated by depleting senescent cells in preclinical studies are frailty, cardiac dysfunction, vascular hyporeactivity and calcification, diabetes mellitus, liver steatosis, osteoporosis, vertebral disk degeneration, pulmonary fibrosis, and radiation‐induced damage. Senolytic agents are being tested in proof‐of‐concept clinical trials. To do so, new clinical trial paradigms for testing senolytics and other agents that target fundamental aging mechanisms are being developed, because use of long‐term endpoints such as lifespan or healthspan is not feasible. These strategies include testing effects on multimorbidity, accelerated aging‐like conditions, diseases with localized accumulation of senescent cells, potentially fatal diseases associated with senescent cell accumulation, age‐related loss of physiological resilience, and frailty. If senolytics or other interventions that target fundamental aging processes prove to be effective and safe in clinical trials, they could transform geriatric medicine by enabling prevention or treatment of multiple diseases and functional deficits in parallel, instead of one at a time.
Cell penetrating peptides (CPP), also known as protein transduction domains (PTD), are small peptides able to carry peptides, proteins, nucleic acid, and nanoparticles, including viral particles, ...across the cellular membranes into cells, resulting in internalization of the intact cargo. In general, CPPs can be broadly classified into tissue-specific and non-tissue specific peptides, with the latter further sub-divided into three types: (1) cationic peptides of 6-12 amino acids in length comprised predominantly of arginine, lysine and/or ornithine residues; (2) hydrophobic peptides such as leader sequences of secreted growth factors or cytokines; and (3) amphipathic peptides obtained by linking hydrophobic peptides to nuclear localizing signals. Tissue-specific peptides are usually identified by screening of large peptide phage display libraries. These transduction peptides have the potential for a myriad of diagnostic as well as therapeutic applications, ranging from delivery of fluorescent or radioactive compounds for imaging, to delivery of peptides and proteins of therapeutic potential, and improving uptake of DNA, RNA, siRNA and even viral particles. Here we review the potential applications as well as hurdles to the tremendous potential of these CPPs, in particular the cell-type specific peptides.
The IGF/mTOR pathway, which is modulated by nutrients, growth factors, energy status and cellular stress regulates aging in various organisms. SIRT1 is a NAD+ dependent deacetylase that is known to ...regulate caloric restriction mediated longevity in model organisms, and has also been linked to the insulin/IGF signaling pathway. Here we investigated the potential regulation of mTOR signaling by SIRT1 in response to nutrients and cellular stress. We demonstrate that SIRT1 deficiency results in elevated mTOR signaling, which is not abolished by stress conditions. The SIRT1 activator resveratrol reduces, whereas SIRT1 inhibitor nicotinamide enhances mTOR activity in a SIRT1 dependent manner. Furthermore, we demonstrate that SIRT1 interacts with TSC2, a component of the mTOR inhibitory-complex upstream to mTORC1, and regulates mTOR signaling in a TSC2 dependent manner. These results demonstrate that SIRT1 negatively regulates mTOR signaling potentially through the TSC1/2 complex.
Almost all cell types release extracellular vesicles (EVs), which are derived either from multivesicular bodies or from the plasma membrane. EVs contain a subset of proteins, lipids, and nucleic ...acids from the cell from which they are derived. EV factors, particularly small RNAs such as miRNAs, likely play important roles in cell-to-cell communication both locally and systemically. Most of the functions associated with EVs are in the regulation of immune responses to pathogens and cancer, as well as in regulating autoimmunity. This Review will focus on the different modes of immune regulation, both direct and indirect, by EVs. The therapeutic utility of EVs for the regulation of immune responses will also be discussed.
Cellular senescence is a cell state implicated in various physiological processes and a wide spectrum of age-related diseases. Recently, interest in therapeutically targeting senescence to improve ...healthy aging and age-related disease, otherwise known as senotherapy, has been growing rapidly. Thus, the accurate detection of senescent cells, especially in vivo, is essential. Here, we present a consensus from the International Cell Senescence Association (ICSA), defining and discussing key cellular and molecular features of senescence and offering recommendations on how to use them as biomarkers. We also present a resource tool to facilitate the identification of genes linked with senescence, SeneQuest (available at http://Senequest.net). Lastly, we propose an algorithm to accurately assess and quantify senescence, both in cultured cells and in vivo.
The cellular state of “senescence” has proven difficult to define, presenting an obstacle for progress in the field. This perspective provides a consensus on the cellular and molecular features of senescence from 26 field leaders.
The concept of geroscience is that since ageing is the greatest risk factor for many diseases and conditions, targeting the ageing process itself will have the greatest impact on human health. Of the ...hallmarks of ageing, cellular senescence has emerged as a druggable therapeutic target for extending healthspan in model organisms. Cellular senescence is a cell state of irreversible proliferative arrest driven by different types of stress, including oncogene‐induced stress. Many senescent cells (SnCs) develop a senescent‐associated secretory phenotype (SASP) comprising pro‐inflammatory cytokines, chemokines, proteases, bioactive lipids, inhibitory molecules, extracellular vesicles, metabolites, lipids and other factors, able to promote chronic inflammation and tissue dysfunction. SnCs up‐regulate senescent cell anti‐apoptotic pathways (SCAPs) that prevent them from dying despite the accumulation of damage to DNA and other organelles. These SCAPs and other pathways altered in SnCs represent therapeutic targets for the development of senotherapeutic drugs that induce selective cell death of SnCs, specifically termed senolytics or suppress markers of senescence, in particular the SASP, termed senomorphics. Here, we review the current state of the development of senolytics and senomorphics for the treatment of age‐related diseases and disorders and extension of healthy longevity. In addition, the challenges of documenting senolytic and senomorphic activity in pre‐clinical models and the current state of the clinical application of the different senotherapeutics will be discussed.
Cellular senescence, a critical hallmark of ageing, has been shown to drive many age‐associated chronic diseases. Senescent cells (SnCs) up‐regulate pathways associated with evasion of apoptosis, survival, senescence‐associated secretory phenotype (SASP) development and others that are targeted using senotherapeutics. Senotherapeutics selectively target SnCs for their clearance (senolytics) or suppression of their SASP (senomorphics). Many studies have demonstrated the benefit of senotherapeutic treatment for the extension of health and lifespan.
Cellular senescence is a hallmark of aging defined by stable exit from the cell cycle in response to cellular damage and stress. Senescent cells (SnCs) can develop a characteristic pathogenic ...senescence-associated secretory phenotype (SASP) that drives secondary senescence and disrupts tissue homeostasis, resulting in loss of tissue repair and regeneration. The use of transgenic mouse models in which SnCs can be genetically ablated has established a key role for SnCs in driving aging and age-related disease. Importantly, senotherapeutics have been developed to pharmacologically eliminate SnCs, termed senolytics, or suppress the SASP and other markers of senescence, termed senomorphics. Based on extensive preclinical studies as well as small clinical trials demonstrating the benefits of senotherapeutics, multiple clinical trials are under way. This Review discusses the role of SnCs in aging and age-related diseases, strategies to target SnCs, approaches to discover and develop senotherapeutics, and preclinical and clinical advances of senolytics.
Immunotherapy using either checkpoint blockade or the adoptive transfer of antitumor lymphocytes has shown effectiveness in treating cancers with high levels of somatic mutations-such as melanoma, ...smoking-induced lung cancers and bladder cancer-with little effect in other common epithelial cancers that have lower mutation rates, such as those arising in the gastrointestinal tract, breast and ovary
. Adoptive transfer of autologous lymphocytes that specifically target proteins encoded by somatically mutated genes has mediated substantial objective clinical regressions in patients with metastatic bile duct, colon and cervical cancers
. We present a patient with chemorefractory hormone receptor (HR)-positive metastatic breast cancer who was treated with tumor-infiltrating lymphocytes (TILs) reactive against mutant versions of four proteins-SLC3A2, KIAA0368, CADPS2 and CTSB. Adoptive transfer of these mutant-protein-specific TILs in conjunction with interleukin (IL)-2 and checkpoint blockade mediated the complete durable regression of metastatic breast cancer, which is now ongoing for >22 months, and it represents a new immunotherapy approach for the treatment of these patients.
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