Macroautophagy (autophagy) is a lysosomal degradation pathway for the breakdown of intracellular proteins and organelles. Although constitutive autophagy is a homeostatic mechanism for intracellular ...recycling and metabolic regulation, autophagy is also stress responsive, in which it is important for the removal of damaged proteins and organelles. Autophagy thereby confers stress tolerance, limits damage, and sustains viability under adverse conditions. Autophagy is a tumor-suppression mechanism, yet it enables tumor cell survival in stress. Reconciling how loss of a prosurvival function can promote tumorigenesis, emerging evidence suggests that preservation of cellular fitness by autophagy may be key to tumor suppression. As autophagy is such a fundamental process, establishing how the functional status of autophagy influences tumorigenesis and treatment response is important. This is especially critical as many current cancer therapeutics activate autophagy. Therefore, efforts to understand and modulate the autophagy pathway will provide new approaches to cancer therapy and prevention.
Chronic liver disease due to alcohol-use disorder contributes markedly to the global burden of disease and mortality
. Alcoholic hepatitis is a severe and life-threatening form of alcohol-associated ...liver disease. The gut microbiota promotes ethanol-induced liver disease in mice
, but little is known about the microbial factors that are responsible for this process. Here we identify cytolysin-a two-subunit exotoxin that is secreted by Enterococcus faecalis
-as a cause of hepatocyte death and liver injury. Compared with non-alcoholic individuals or patients with alcohol-use disorder, patients with alcoholic hepatitis have increased faecal numbers of E. faecalis. The presence of cytolysin-positive (cytolytic) E. faecalis correlated with the severity of liver disease and with mortality in patients with alcoholic hepatitis. Using humanized mice that were colonized with bacteria from the faeces of patients with alcoholic hepatitis, we investigated the therapeutic effects of bacteriophages that target cytolytic E. faecalis. We found that these bacteriophages decrease cytolysin in the liver and abolish ethanol-induced liver disease in humanized mice. Our findings link cytolytic E. faecalis with more severe clinical outcomes and increased mortality in patients with alcoholic hepatitis. We show that bacteriophages can specifically target cytolytic E. faecalis, which provides a method for precisely editing the intestinal microbiota. A clinical trial with a larger cohort is required to validate the relevance of our findings in humans, and to test whether this therapeutic approach is effective for patients with alcoholic hepatitis.
A Highly Durable RNAi Therapeutic Inhibitor of PCSK9 Fitzgerald, Kevin; White, Suellen; Borodovsky, Anna ...
New England journal of medicine/The New England journal of medicine,
01/2017, Letnik:
376, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Inclisiran (ALN-PCSsc) is a long-acting RNA interference (RNAi) therapeutic agent that inhibits the synthesis of proprotein convertase subtilisin-kexin type 9 (PCSK9), a target for the lowering of ...low-density lipoprotein (LDL) cholesterol.
In this phase 1 trial, we randomly assigned healthy volunteers with an LDL cholesterol level of at least 100 mg per deciliter in a 3:1 ratio to receive a subcutaneous injection of inclisiran or placebo in either a single-ascending-dose phase (at a dose of 25, 100, 300, 500, or 800 mg) or a multiple-dose phase (125 mg weekly for four doses, 250 mg every other week for two doses, or 300 or 500 mg monthly for two doses, with or without concurrent statin therapy); each dose cohort included four to eight participants. Safety, the side-effect profile, and pharmacodynamic measures (PCSK9 level, LDL cholesterol level, and exploratory lipid variables) were evaluated.
The most common adverse events were cough, musculoskeletal pain, nasopharyngitis, headache, back pain, and diarrhea. All the adverse events were mild or moderate in severity. There were no serious adverse events or discontinuations due to adverse events. There was one grade 3 elevation in the γ-glutamyltransferase level, which was considered by the investigator to be related to statin therapy. In the single-dose phase, inclisiran doses of 300 mg or more reduced the PCSK9 level (up to a least-squares mean reduction of 74.5% from baseline to day 84), and doses of 100 mg or more reduced the LDL cholesterol level (up to a least-squares mean reduction of 50.6% from baseline). Reductions in the levels of PCSK9 and LDL cholesterol were maintained at day 180 for doses of 300 mg or more. All multiple-dose regimens reduced the levels of PCSK9 (up to a least-squares mean reduction of 83.8% from baseline to day 84) and LDL cholesterol (up to a least-squares mean reduction of 59.7% from baseline to day 84).
In this phase 1 trial, no serious adverse events were observed with inclisiran. Doses of 300 mg or more (in single or multiple doses) significantly reduced levels of PCSK9 and LDL cholesterol for at least 6 months. (Funded by Alnylam Pharmaceuticals and the Medicines Company; ClinicalTrials.gov number, NCT02314442 .).
Summary Background Cangrelor is a potent, rapid-acting, reversible intravenous platelet inhibitor that was tested for percutaneous coronary intervention (PCI) in three large, double-blind, randomised ...trials. We did a pooled analysis of data from three trials that assessed the effectiveness of cangrelor against either clopidogrel or placebo in PCI. Methods This prespecified, pooled analysis of patient-level data from three trials (CHAMPION-PCI, CHAMPION-PLATFORM, and CHAMPION-PHOENIX) compared cangrelor with control (clopidogrel or placebo) for prevention of thrombotic complications during and after PCI. Trial participants were patients undergoing PCI for ST-elevation myocardial infarction (11·6%), non-ST-elevation acute coronary syndromes (57·4%), and stable coronary artery disease (31·0%). Efficacy was assessed in the modified intention-to-treat population of 24 910 patients, with a prespecified primary efficacy composite of death, myocardial infarction, ischaemia-driven revascularisation, or stent thrombosis at 48 h. The primary safety outcome was non-coronary artery bypass graft-related GUSTO (Global Use of Strategies to Open Occluded Coronary Arteries) severe or life-threatening bleeding at 48 h. Findings Cangrelor reduced the odds of the primary outcome by 19% (3·8% for cangrelor vs 4·7% for control; odds ratio OR 0·81, 95% CI 0·71–0·91, p=0·0007), and stent thrombosis by 41% (0·5% vs 0·8%, OR 0·59, 95% CI 0·43–0·80, p=0·0008). Cangrelor reduced the odds of the secondary triple composite (all-cause death, myocardial infarction, or ischaemia-driven revascularisation at 48 h) by 19% (3·6% vs 4·4%, OR 0·81, 95% CI 0·71–0·92, p=0·0014). Efficacy outcomes were consistent across the trials and main patient subsets. These benefits were maintained at 30 days. There was no difference in the primary safety outcome (0·2% in both groups), in GUSTO moderate bleeding (0·6% vs 0·4%), or in transfusion (0·7% vs 0·6%), but cangrelor increased GUSTO mild bleeding (16·8% vs 13·0%, p<0·0001). Interpretation Compared with control (clopidogrel or placebo), cangrelor reduced PCI periprocedural thrombotic complications, at the expense of increased bleeding. Funding The Medicines Company.
Antibodies that target the immune checkpoint receptor programmed cell death protein 1 (PD-1) have resulted in prolonged and beneficial responses toward a variety of human cancers. However, anti-PD-1 ...therapy in some patients provides no benefit and/or results in adverse side effects. The factors that determine whether patients will be drug sensitive or resistant are not fully understood; therefore, genomic assessment of exceptional responders can provide important insight into patient response. Here, we identified a patient with endometrial cancer who had an exceptional response to the anti-PD-1 antibody pembrolizumab. Clinical grade targeted genomic profiling of a pretreatment tumor sample from this individual identified a mutation in DNA polymerase epsilon (POLE) that associated with an ultramutator phenotype. Analysis of The Cancer Genome Atlas (TCGA) revealed that the presence of POLE mutation associates with high mutational burden and elevated expression of several immune checkpoint genes. Together, these data suggest that cancers harboring POLE mutations are good candidates for immune checkpoint inhibitor therapy.
Infections, inflammation and epilepsy Vezzani, Annamaria; Fujinami, Robert S.; White, H. Steve ...
Acta Neuropathologica,
02/2016, Letnik:
131, Številka:
2
Journal Article, Book Review
Recenzirano
Odprti dostop
Epilepsy is the tendency to have unprovoked epileptic seizures. Anything causing structural or functional derangement of brain physiology may lead to seizures, and different conditions may express ...themselves solely by recurrent seizures and thus be labelled “epilepsy.” Worldwide, epilepsy is the most common serious neurological condition. The range of risk factors for the development of epilepsy varies with age and geographic location. Congenital, developmental and genetic conditions are mostly associated with the development of epilepsy in childhood, adolescence and early adulthood. Head trauma, infections of the central nervous system (CNS) and tumours may occur at any age and may lead to the development of epilepsy. Infections of the CNS are a major risk factor for epilepsy. The reported risk of unprovoked seizures in population-based cohorts of survivors of CNS infections from developed countries is between 6.8 and 8.3 %, and is much higher in resource-poor countries. In this review, the various viral, bacterial, fungal and parasitic infectious diseases of the CNS which result in seizures and epilepsy are discussed. The pathogenesis of epilepsy due to brain infections, as well as the role of experimental models to study mechanisms of epileptogenesis induced by infectious agents, is reviewed. The sterile (non-infectious) inflammatory response that occurs following brain insults is also discussed, as well as its overlap with inflammation due to infections, and the potential role in epileptogenesis. Furthermore, autoimmune encephalitis as a cause of seizures is reviewed. Potential strategies to prevent epilepsy resulting from brain infections and non-infectious inflammation are also considered.
Antisemitism: A psychoanalytic theory White, Robert S.
International journal of applied psychoanalytic studies,
04/2024, Letnik:
21, Številka:
1
Journal Article
Recenzirano
Abstract Antisemitism has been a persistent and growing prejudice for millenniums against the Jewish people. This paper offers a general theory of group hatred appliable to antisemitism and other ...religious or racial prejudices. Theories of prejudice tend either to postulate an internal psychic template of hatred that is projected or postulate a social origin of hatred that is internalized. Rather there is a dialectic where there is a reciprocal movement between internal and external. The tendency to hate and project is a part of the human psyche, here called internal racism. Anxieties which cannot be contained internally can be stabilized by large‐group identity. When internal racism cannot be contained or the external social groups are weak, the result is pathological large‐group formations. A distinction can be made between personal antisemitism in which the hatred is projected onto a known person and impersonal antisemitism in which hatred is projected into groups. A fairy tale by the brother's Grimm, “The Jew among Thorns” is used to illustrate a number of personal antisemitic attitudes. “The Protocols of the Elders of Zion,” a forged document that appeared in pre‐revolutionary Russia, is used to illustrate impersonal antisemitism.
Heterozygous somatic mutations in the spliceosome gene U2AF1 occur in ∼11% of patients with myelodysplastic syndromes (MDS), the most common adult myeloid malignancy. It is unclear how these ...mutations contribute to disease. We examined in vivo hematopoietic consequences of the most common U2AF1 mutation using a doxycycline-inducible transgenic mouse model. Mice expressing mutant U2AF1(S34F) display altered hematopoiesis and changes in pre-mRNA splicing in hematopoietic progenitor cells by whole transcriptome analysis (RNA-seq). Integration with human RNA-seq datasets determined that common mutant U2AF1-induced splicing alterations are enriched in RNA processing genes, ribosomal genes, and recurrently mutated MDS and acute myeloid leukemia-associated genes. These findings support the hypothesis that mutant U2AF1 alters downstream gene isoform expression, thereby contributing to abnormal hematopoiesis in patients with MDS.
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•U2AF1 mutant mice develop leukopenia and hematopoietic progenitor cell expansion•U2AF1 mutant stem cells are outcompeted by wild-type stem cells in vivo•Mutant U2AF1 alters splicing similarly in mouse and human hematopoietic cells•Mutant U2AF1 alters splicing of RNA processing and recurrently mutated MDS/AML genes
Shirai et al. show that the U2AF1 mutation most commonly found in myelodysplastic syndromes (MDS) alters pre-mRNA splicing in RNA processing genes, ribosomal genes, and recurrently mutated MDS and acute myeloid leukemia-associated genes in hematopoietic progenitor cells and affects hematopoiesis.
Macroautophagy (autophagy hereafter) degrades and recycles proteins and organelles to support metabolism and survival in starvation. Oncogenic Ras up-regulates autophagy, and Ras-transformed cell ...lines require autophagy for mitochondrial function, stress survival, and engrafted tumor growth. Here, the essential autophagy gene autophagy-related-7 (atg7) was deleted concurrently with K-ras(G12D) activation in mouse models for non-small-cell lung cancer (NSCLC). atg7-deficient tumors accumulated dysfunctional mitochondria and prematurely induced p53 and proliferative arrest, which reduced tumor burden that was partly relieved by p53 deletion. atg7 loss altered tumor fate from adenomas and carcinomas to oncocytomas-rare, predominantly benign tumors characterized by the accumulation of defective mitochondria. Surprisingly, lipid accumulation occurred in atg7-deficient tumors only when p53 was deleted. atg7- and p53-deficient tumor-derived cell lines (TDCLs) had compromised starvation survival and formed lipidic cysts instead of tumors, suggesting defective utilization of lipid stores. atg7 deficiency reduced fatty acid oxidation (FAO) and increased sensitivity to FAO inhibition, indicating that with p53 loss, Ras-driven tumors require autophagy for mitochondrial function and lipid catabolism. Thus, autophagy is required for carcinoma fate, and autophagy defects may be a molecular basis for the occurrence of oncocytomas. Moreover, cancers require autophagy for distinct roles in metabolism that are oncogene- and tumor suppressor gene-specific.
Autophagy is a catabolic pathway used by cells to support metabolism in response to starvation and to clear damaged proteins and organelles in response to stress. We report here that expression of a ...H-ras(V12) or K-ras(V12) oncogene up-regulates basal autophagy, which is required for tumor cell survival in starvation and in tumorigenesis. In Ras-expressing cells, defective autophagosome formation or cargo delivery causes accumulation of abnormal mitochondria and reduced oxygen consumption. Autophagy defects also lead to tricarboxylic acid (TCA) cycle metabolite and energy depletion in starvation. As mitochondria sustain viability of Ras-expressing cells in starvation, autophagy is required to maintain the pool of functional mitochondria necessary to support growth of Ras-driven tumors. Human cancer cell lines bearing activating mutations in Ras commonly have high levels of basal autophagy, and, in a subset of these, down-regulating the expression of essential autophagy proteins impaired cell growth. As cancers with Ras mutations have a poor prognosis, this "autophagy addiction" suggests that targeting autophagy and mitochondrial metabolism are valuable new approaches to treat these aggressive cancers.
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