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Evidence-based Complementary and... 2020At present, the relationship between autophagosomes and the prognosis of various cancers has become a subject of active investigation. A series of studies have... (Review)
Review
OBJECTIVE
At present, the relationship between autophagosomes and the prognosis of various cancers has become a subject of active investigation. A series of studies have demonstrated the correlation between autophagy microtubule-associated protein light chain 3 (LC-3), Beclin-1, and colorectal cancer (CRC). Since autophagy has dual regulatory roles in tumors, the results of this correlation are also uncertain. Hence, we summarized the relationship between Beclin-1, LC-3, and CRC using systematic reviews and meta-analysis to clarify their prognostic significance in it.
METHODS
PubMed, EMBASE, Cochrane Library, and Web of Science databases were searched online up to April 1, 2019. The quality of the involving studies was assessed against the Newcastle-Ottawa Scale (NOS). Pooled hazard ratio (HR) and 95% confidence interval (CI) in a fixed or random effects model were used to assess the strength of correlation between Beclin-1, LC-3, and CRC.
RESULTS
A total of 9 articles were collected, involving 2,297 patients. Most literatures scored more than 6 points, suggesting that the quality of our including research was acceptable. Our finding suggested that the expression of Beclin-1 was not associated with overall survival (HR = 0.68, 95% CI (0.31-1.52), =0.351). Nonetheless, LC-3 expression exerted significant impact on OS (HR = 0.51, 95% CI (0.35-0.74), < 0.05). Subgroup analysis exhibited that Beclin-1 expression was associated with OS at TNM stage III (HR = 0.04, 95% CI = 0.02-0.08, < 0.05), surgical treatment (HR = 1.53, 95% CI (1.15-2.02), =0.003), and comprehensive treatment (HR = 0.27 95% CI (0.08-0.92), =0.036), respectively. Similarly, the results showed the increased LC-3 expression in CRC was related to OS in multivariate analyses (HR = 0.44, 95% CI (0.34-0.57), < 0.05), stages (HR = 0.51, 95% CI (0.35-0.74), < 0.05), and comprehensive treatment (HR = 0.44, 95% CI (0.34-0.57), < 0.05).
CONCLUSIONS
Autophagy-related proteins of LC-3 might be an important marker of CRC progression. However, since the number of the original studies was limited, more well-designed, large-scale, high-quality studies are warranted to provide more convincing and reliable information.
PubMed: 32280357
DOI: 10.1155/2020/8475840 -
Apoptosis : An International Journal on... Dec 2018Autophagy is an evolutionarily conserved catabolic process that plays an essential role in maintaining cellular homeostasis by degrading unneeded cell components. When... (Review)
Review
Autophagy is an evolutionarily conserved catabolic process that plays an essential role in maintaining cellular homeostasis by degrading unneeded cell components. When exposed to hostile environments, such as hypoxia or nutrient starvation, cells hyperactivate autophagy in an effort to maintain their longevity. In densely packed solid tumors, such as glioblastoma, autophagy has been found to run rampant due to a lack of oxygen and nutrients. In recent years, targeting autophagy as a way to strengthen current glioblastoma treatment has shown promising results. However, that protective autophagy inhibition or autophagy overactivation is more beneficial, is still being debated. Protective autophagy inhibition would lower a cell's previously activated defense mechanism, thereby increasing its sensitivity to treatment. Autophagy overactivation would cause cell death through lysosomal overactivation, thus introducing another cell death pathway in addition to apoptosis. Both methods have been proven effective in the treatment of solid tumors. This systematic review article highlights scenarios where both autophagy inhibition and activation have proven effective in combating chemoresistance and radioresistance in glioblastoma, and how autophagy may be best utilized for glioblastoma therapy in clinical settings.
Topics: Antineoplastic Agents; Autophagosomes; Autophagy; Brain Neoplasms; Cell Death; Drug Resistance, Neoplasm; Glioblastoma; Humans; Radiation-Sensitizing Agents; Temozolomide
PubMed: 30171377
DOI: 10.1007/s10495-018-1480-9 -
Nutrients Jan 2021Vitamin D is an essential component of immune function and childhood deficiency is associated with an increased risk of acute lower respiratory infections (ALRIs)....
Vitamin D is an essential component of immune function and childhood deficiency is associated with an increased risk of acute lower respiratory infections (ALRIs). Globally, the leading childhood respiratory pathogens are , respiratory syncytial virus and the influenza virus. There is a growing body of evidence describing the innate immunomodulatory properties of vitamin D during challenge with respiratory pathogens, but recent systematic and unbiased synthesis of data is lacking, and future research directions are unclear. We therefore conducted a systematic PubMed literature search using the terms "vitamin D" and "" or "Respiratory Syncytial Virus" or "Influenza". A priori inclusion criteria restricted the review to in vitro studies investigating the effect of vitamin D metabolites on human innate immune cells (primary, differentiated or immortalised) in response to stimulation with the specified respiratory pathogens. Eleven studies met our criteria. Despite some heterogeneity across pathogens and innate cell types, vitamin D modulated pathogen recognition receptor (PRRs: Toll-like receptor 2 (TLR2), TLR4, TLR7 and nucleotide-binding oligomerisation domain-containing protein 2 (NOD2)) expression; increased antimicrobial peptide expression (LL-37, human neutrophil peptide (HNP) 1-3 and β-defensin); modulated autophagosome production reducing apoptosis; and modulated production of inflammatory cytokines (Interleukin (IL) -1β, tumour necrosis factor-α (TNF-α), interferon-ɣ (IFN-ɣ), IL-12p70, IFN-β, Regulated on Activation, Normal T cell Expressed (RANTES), IL-10) and chemokines (IL-8 and C-X-C motif chemokine ligand 10 (CXCL10)). Differential modulation of PRRs and IL-1β was reported across immune cell types; however, this may be due to the experimental design. None of the studies specifically focused on immune responses in cells derived from children. In summary, vitamin D promotes a balanced immune response, potentially enhancing pathogen sensing and clearance and restricting pathogen induced inflammatory dysregulation. This is likely to be important in controlling both ALRIs and the immunopathology associated with poorer outcomes and progression to chronic lung diseases. Many unknowns remain and further investigation is required to clarify the nuances in vitamin D mediated immune responses by pathogen and immune cell type and to determine whether these in vitro findings translate into enhanced immunity and reduced ALRI in the paediatric clinical setting.
Topics: Child; Child, Preschool; Cytokines; Humans; Immunity, Innate; Immunomodulation; Infant; Influenza A virus; Influenza, Human; Pneumonia, Pneumococcal; Respiratory Syncytial Virus Infections; Respiratory Syncytial Viruses; Respiratory Tract Infections; Streptococcus pneumoniae; Vitamin D
PubMed: 33478006
DOI: 10.3390/nu13010276 -
Cells Sep 2020Autophagy, a conserved process in which cells break down and destroy old, damaged, or abnormal proteins and other substances in the cytoplasm through lysosomal...
Autophagy, a conserved process in which cells break down and destroy old, damaged, or abnormal proteins and other substances in the cytoplasm through lysosomal degradation, occurs via autophagosome formation and aids in the maintenance of intracellular homeostasis. Autophagy is closely associated with hepatitis B virus (HBV) replication and assembly. Currently, HBV infection is still one of the most serious public health issues worldwide. The unavailability of satisfactory therapeutic strategies for chronic HBV infection indicates an urgent need to elucidate the mechanisms underlying the pathogenesis of HBV infection. Increasing evidence has shown that HBV not only possesses the ability to induce incomplete autophagy but also evades autophagic degradation, indicating that HBV utilizes or hijacks the autophagy machinery for its own replication. Therefore, autophagy might be a crucial target pathway for controlling HBV infection. The definite molecular mechanisms underlying the association between cellular autophagy and HBV replication require further clarification. In this review, we have summarized and discussed the latest findings on the interplay between autophagy and HBV replication.
Topics: Animals; Antiviral Agents; Apoptosis; Autophagosomes; Autophagy; Hepatitis B virus; Hepatitis B, Chronic; Host Microbial Interactions; Humans; Lysosomes; Mice; Trans-Activators; Viral Regulatory and Accessory Proteins; Virion; Virus Replication
PubMed: 32942717
DOI: 10.3390/cells9092101 -
Frontiers in Molecular Neuroscience 2021A typical neuron consists of a soma, a single axon with numerous nerve terminals, and multiple dendritic trunks with numerous branches. Each of the 100 billion neurons...
A typical neuron consists of a soma, a single axon with numerous nerve terminals, and multiple dendritic trunks with numerous branches. Each of the 100 billion neurons in the brain has on average 7,000 synaptic connections to other neurons. The neuronal endolysosomal compartments for the degradation of axonal and dendritic waste are located in the soma region. That means that all autophagosomal and endosomal cargos from 7,000 synaptic connections must be transported to the soma region for degradation. For that reason, neuronal endolysosomal degradation is an extraordinarily demanding and dynamic event, and thus is highly susceptible to many pathological conditions. Dysfunction in the endolysosomal trafficking pathways occurs in virtually all neurodegenerative diseases. Most lysosomal storage disorders (LSDs) with defects in the endolysosomal system preferentially affect the central nervous system (CNS). Recently, significant progress has been made in understanding the role that the endolysosomal trafficking pathways play after brain ischemia. Brain ischemia damages the membrane fusion machinery co-operated by N-ethylmaleimide sensitive factor (NSF), soluble NSF attachment protein (SNAP), and soluble NSF attachment protein receptors (SNAREs), thus interrupting the membrane-to-membrane fusion between the late endosome and terminal lysosome. This interruption obstructs all incoming traffic. Consequently, both the size and number of endolysosomal structures, autophagosomes, early endosomes, and intra-neuronal protein aggregates are increased extensively in post-ischemic neurons. This cascade of events eventually damages the endolysosomal structures to release hydrolases leading to ischemic brain injury. Gene knockout and selective inhibition of key endolysosomal cathepsins protects the brain from ischemic injury. This review aims to provide an update of the current knowledge, future research directions, and the clinical implications regarding the critical role of the neuronal endolysosomal trafficking pathways in ischemic brain injury.
PubMed: 34650402
DOI: 10.3389/fnmol.2021.719100 -
European Review For Medical and... Feb 2021Autophagy is a main metabolic process in which eukaryotic cells use lysosomes to eliminate abnormal proteins and damaged organelles to maintain cell homeostasis. Studies...
Autophagy is a main metabolic process in which eukaryotic cells use lysosomes to eliminate abnormal proteins and damaged organelles to maintain cell homeostasis. Studies have revealed that neurodegenerative diseases, tumor, hepatic diseases, etc. are related to abnormal autophagy processes in recent years. Recent studies have shown that TFEB is a major transcription regulator of autophagy-lysosomal pathway (ALP) transcriptional regulation, which positively regulates the expression of autophagy and lysosomal biogenesis-related genes, thereby promoting autophagosome formation, autophagosome-lysosome fusion, and degradation of autophagy substrates. It has also been found that TFEB promotes clearance of intracellular substrates through lysosomal exocytosis. Therefore, the study of biological functions and related regulatory mechanisms of TFEB will provide important clues and theoretical basis for further explaining its physiological pathogenesis and the treatment of related diseases.
Topics: Animals; Autophagy; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; Humans; Lysosomes; Neoplasms; Neurodegenerative Diseases
PubMed: 33629334
DOI: 10.26355/eurrev_202102_24875 -
Frontiers in Genetics 2022Heparan sulfate modified proteins or proteoglycans (HSPGs) are an abundant class of cell surface and extracellular matrix molecules. They serve important co-receptor...
Heparan sulfate modified proteins or proteoglycans (HSPGs) are an abundant class of cell surface and extracellular matrix molecules. They serve important co-receptor functions in the regulation of signaling as well as membrane trafficking. Many of these activities directly affect processes associated with neurodegeneration including uptake and export of Tau protein, disposition of Amyloid Precursor Protein-derived peptides, and regulation of autophagy. In this review we focus on the impact of HSPGs on autophagy, membrane trafficking, mitochondrial quality control and biogenesis, and lipid metabolism. Disruption of these processes are a hallmark of Alzheimer's disease (AD) and there is evidence that altering heparan sulfate structure and function could counter AD-associated pathological processes. Compromising presenilin function in several systems has provided instructive models for understanding the molecular and cellular underpinnings of AD. Disrupting presenilin function produces a constellation of cellular deficits including accumulation of lipid, disruption of autophagosome to lysosome traffic and reduction in mitochondrial size and number. Inhibition of heparan sulfate biosynthesis has opposing effects on all these cellular phenotypes, increasing mitochondrial size, stimulating autophagy flux to lysosomes, and reducing the level of intracellular lipid. These findings suggest a potential mechanism for countering pathology found in AD and related disorders by altering heparan sulfate structure and influencing cellular processes disrupted broadly in neurodegenerative disease. Vertebrate and invertebrate model systems, where the cellular machinery of autophagy and lipid metabolism are conserved, continue to provide important translational guideposts for designing interventions that address the root cause of neurodegenerative pathology.
PubMed: 36699460
DOI: 10.3389/fgene.2022.1012706 -
Basic & Clinical Pharmacology &... Jan 2022Efficient delivery of brain-targeted drugs is highly important for the success of therapies in neurodegenerative diseases. Borneol has several biological activities,...
Efficient delivery of brain-targeted drugs is highly important for the success of therapies in neurodegenerative diseases. Borneol has several biological activities, such as anti-inflammatory and cell penetration enhancing effect, and can regulate processes in the neurovascular unit (NVU), such as protein toxic stress, autophagosome/lysosomal system, oxidative stress, programmed cell death and neuroinflammation. However, the influence of borneol on NVU in neurodegenerative diseases has not been fully explained. This study searched the keywords 'borneol', 'neurovascular unit', 'endothelial cell', 'astrocyte', 'neuron', 'blood-brain barrier', 'neurodegenerative diseases' and 'brain disease' in PubMed, BioMed Central, China National Knowledge Infrastructure (CNKI) and Bing search engines to explore the influence of borneol on NVU. In addition to the principle and mechanism of penetration of borneol in the brain, this study also showed its multiple regulation effects on NVU. Borneol was able to penetrate the blood-brain barrier (BBB), affecting the signal transmission between BBB and the microenvironment of the brain, downregulating the expression of inflammatory and oxidative stress proteins in NVU, especially in microglia and astrocytes. In summary, borneol is a potential drug delivery agent for drugs against neurodegenerative diseases.
Topics: Animals; Astrocytes; Blood-Brain Barrier; Brain; Camphanes; Drug Delivery Systems; Humans; Microglia; Neurodegenerative Diseases; Tissue Distribution
PubMed: 34491621
DOI: 10.1111/bcpt.13656