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Showing papers in "MedComm in 2022"


Journal ArticleDOI
01 Mar 2022-MedComm
TL;DR: A comprehensive analysis and summary of the epidemiology and immune escape mechanisms of the Omicron variant is provided, which poses significant challenges for the clinical effectiveness of the current vaccines and therapeutic antibodies.
Abstract: Abstract New genetic variants of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) constantly emerge through unmitigated spread of the virus in the ongoing Coronavirus disease 2019 pandemic. Omicron (B.1.1.529), the latest variant of concern (VOC), has so far shown exceptional spread and infectivity and has established itself as the dominant variant in recent months. The SARS‐CoV‐2 spike glycoprotein is a key component for the recognition and binding to host cell angiotensin‐converting enzyme 2 receptors. The Omicron variant harbors a cluster of substitutions/deletions/insertions, and more than 30 mutations are located in spike. Some noticeable mutations, including K417N, T478K, N501Y, and P681H, are shared with the previous VOCs Alpha, Beta, Gamma, or Delta variants and have been proven to be associated with higher transmissibility, viral infectivity, and immune evasion potential. Studies have revealed that the Omicron variant is partially resistant to the neutralizing activity of therapeutic antibodies and convalescent sera, which poses significant challenges for the clinical effectiveness of the current vaccines and therapeutic antibodies. We provide a comprehensive analysis and summary of the epidemiology and immune escape mechanisms of the Omicron variant. We also suggest some therapeutic strategies against the Omicron variant. This review, therefore, aims to provide information for further research efforts to prevent and contain the impact of new VOCs during the ongoing pandemic.

55 citations


Journal ArticleDOI
11 Feb 2022-MedComm
TL;DR: A perspective article carefully and critically summarizes the Omicron's origin, structure, pathogenesis, impact health along with health systems, and experts’ recommendations to manage it successfully.
Abstract: Abstract Since early 2020, coronavirus diseases 2019 (COVID‐19) infection pandemic/endemic is constantly surprising health experts because of continuous variations in the structures of severe acute respiratory coronavirus 2 (SARS‐CoV‐2) in the form of newly emerged variants. Such mutations have exhibited high mortality and severity due to the newly emerged more infectious sites of SARS‐CoV‐2, making viral infection more transmissible, infectious, and severe. Recently, SARS‐CoV‐2 mutated to another variant, namely, Omicron (B.1.1.529), which is many times more transmissible and infectious than existed deadly Delta variants of the virus. This severity is closely correlated to a larger number of mutations observed in the receptor‐binding domain of the spike protein of the Omicron‐SARS‐CoV‐2. Considering severity, Omicron has been declared as variant of concerns by the World Health Organization and within days from its emergence, Omicron infection has spread globally, increased hospitalization, exhibited more severity for the young generation, invaded defense mechanism of natural immunity, not responsive to the available vaccines. Such circumstances resonated with the efficiency of available strategies established to manage COVID‐19 intelligently and successfully. To explore these aspects, this perspective article carefully and critically summarizes the Omicron's origin, structure, pathogenesis, impact health along with health systems, and experts’ recommendations to manage it successfully.

41 citations


Journal ArticleDOI
14 Jul 2022-MedComm
TL;DR: All information and knowledge presented here are very helpful for understanding the structural features and inhibitory mechanisms of SARS‐CoV‐2 3CLpro inhibitors, which offers new insights or inspiration to medicinal chemists for designing and developing more efficacious 3CL Pro inhibitors as novel anti‐coronavirus agents.
Abstract: Abstract The main proteases (Mpro), also termed 3‐chymotrypsin‐like proteases (3CLpro), are a class of highly conserved cysteine hydrolases in β‐coronaviruses. Increasing evidence has demonstrated that 3CLpros play an indispensable role in viral replication and have been recognized as key targets for preventing and treating coronavirus‐caused infectious diseases, including COVID‐19. This review is focused on the structural features and biological function of the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) main protease Mpro (also known as 3CLpro), as well as recent advances in discovering and developing SARS‐CoV‐2 3CLpro inhibitors. To better understand the characteristics of SARS‐CoV‐2 3CLpro inhibitors, the inhibition activities, inhibitory mechanisms, and key structural features of various 3CLpro inhibitors (including marketed drugs, peptidomimetic, and non‐peptidomimetic synthetic compounds, as well as natural compounds and their derivatives) are summarized comprehensively. Meanwhile, the challenges in this field are highlighted, while future directions for designing and developing efficacious 3CLpro inhibitors as novel anti‐coronavirus therapies are also proposed. Collectively, all information and knowledge presented here are very helpful for understanding the structural features and inhibitory mechanisms of SARS‐CoV‐2 3CLpro inhibitors, which offers new insights or inspiration to medicinal chemists for designing and developing more efficacious 3CLpro inhibitors as novel anti‐coronavirus agents.

37 citations


Journal ArticleDOI
31 Mar 2022-MedComm
TL;DR: The roles of ROS as multifaceted physiological modulators to mediate redox signaling and sustain redox homeostasis are revealed and two different therapeutic strategies to treat redox‐relevant diseases are suggested.
Abstract: Abstract Redox biology is at the core of life sciences, accompanied by the close correlation of redox processes with biological activities. Redox homeostasis is a prerequisite for human health, in which the physiological levels of nonradical reactive oxygen species (ROS) function as the primary second messengers to modulate physiological redox signaling by orchestrating multiple redox sensors. However, excessive ROS accumulation, termed oxidative stress (OS), leads to biomolecule damage and subsequent occurrence of various diseases such as type 2 diabetes, atherosclerosis, and cancer. Herein, starting with the evolution of redox biology, we reveal the roles of ROS as multifaceted physiological modulators to mediate redox signaling and sustain redox homeostasis. In addition, we also emphasize the detailed OS mechanisms involved in the initiation and development of several important diseases. ROS as a double‐edged sword in disease progression suggest two different therapeutic strategies to treat redox‐relevant diseases, in which targeting ROS sources and redox‐related effectors to manipulate redox homeostasis will largely promote precision medicine. Therefore, a comprehensive understanding of the redox signaling networks under physiological and pathological conditions will facilitate the development of redox medicine and benefit patients with redox‐relevant diseases.

30 citations


Journal ArticleDOI
02 Aug 2022-MedComm
TL;DR: How the HSPs keep the protein proteostasis and response to stresses, and their roles in diseases and the recent exploration of HSP related therapy and diagnosis to modulate diseases are discussed.
Abstract: Abstract The heat shock proteins (HSPs) are ubiquitous and conserved protein families in both prokaryotic and eukaryotic organisms, and they maintain cellular proteostasis and protect cells from stresses. HSP protein families are classified based on their molecular weights, mainly including large HSPs, HSP90, HSP70, HSP60, HSP40, and small HSPs. They function as molecular chaperons in cells and work as an integrated network, participating in the folding of newly synthesized polypeptides, refolding metastable proteins, protein complex assembly, dissociating protein aggregate dissociation, and the degradation of misfolded proteins. In addition to their chaperone functions, they also play important roles in cell signaling transduction, cell cycle, and apoptosis regulation. Therefore, malfunction of HSPs is related with many diseases, including cancers, neurodegeneration, and other diseases. In this review, we describe the current understandings about the molecular mechanisms of the major HSP families including HSP90/HSP70/HSP60/HSP110 and small HSPs, how the HSPs keep the protein proteostasis and response to stresses, and we also discuss their roles in diseases and the recent exploration of HSP related therapy and diagnosis to modulate diseases. These research advances offer new prospects of HSPs as potential targets for therapeutic intervention.

30 citations


Journal ArticleDOI
18 May 2022-MedComm
TL;DR: EMT confers cancer cells with increased metastatic potential and drug resistant capacity, which accounts for tumor recurrence in most clinic cases, and targeting EMT can be a therapeutic option providing a chance of cure for cancer patients.
Abstract: Abstract Epithelial–mesenchymal transition (EMT) is a program wherein epithelial cells lose their junctions and polarity while acquiring mesenchymal properties and invasive ability. Originally defined as an embryogenesis event, EMT has been recognized as a crucial process in tumor progression. During EMT, cell–cell junctions and cell–matrix attachments are disrupted, and the cytoskeleton is remodeled to enhance mobility of cells. This transition of phenotype is largely driven by a group of key transcription factors, typically Snail, Twist, and ZEB, through epigenetic repression of epithelial markers, transcriptional activation of matrix metalloproteinases, and reorganization of cytoskeleton. Mechanistically, EMT is orchestrated by multiple pathways, especially those involved in embryogenesis such as TGFβ, Wnt, Hedgehog, and Hippo, suggesting EMT as an intrinsic link between embryonic development and cancer progression. In addition, redox signaling has also emerged as critical EMT modulator. EMT confers cancer cells with increased metastatic potential and drug resistant capacity, which accounts for tumor recurrence in most clinic cases. Thus, targeting EMT can be a therapeutic option providing a chance of cure for cancer patients. Here, we introduce a brief history of EMT and summarize recent advances in understanding EMT mechanisms, as well as highlighting the therapeutic opportunities by targeting EMT in cancer treatment.

27 citations


Journal ArticleDOI
23 Mar 2022-MedComm
TL;DR: The history, research advances, and prospects concerning the STAT3 pathway in cancer, and the emerging development of inhibitors that target theSTAT3 pathway and novel drug delivery systems for delivering these inhibitors are introduced.
Abstract: Abstract Signal transducer and activator of transcription 3 (STAT3), a member of the STAT family, discovered in the cytoplasm of almost all types of mammalian cells, plays a significant role in biological functions. The duration of STAT3 activation in normal tissues is a transient event and is strictly regulated. However, in cancer tissues, STAT3 is activated in an aberrant manner and is induced by certain cytokines. The continuous activation of STAT3 regulates the expression of downstream proteins associated with the formation, progression, and metastasis of cancers. Thus, elucidating the mechanisms of STAT3 regulation and designing inhibitors targeting the STAT3 pathway are considered promising strategies for cancer treatment. This review aims to introduce the history, research advances, and prospects concerning the STAT3 pathway in cancer. We review the mechanisms of STAT3 pathway regulation and the consequent cancer hallmarks associated with tumor biology that are induced by the STAT3 pathway. Moreover, we summarize the emerging development of inhibitors that target the STAT3 pathway and novel drug delivery systems for delivering these inhibitors. The barriers against targeting the STAT3 pathway, the focus of future research on promising targets in the STAT3 pathway, and our perspective on the overall utility of STAT3 pathway inhibitors in cancer treatment are also discussed.

24 citations


Journal ArticleDOI
10 Jul 2022-MedComm
TL;DR: This review will focus on the latest development of autophagy research, covering molecular mechanisms in control of autphagosome biogenesis and autophagosome–lysosome fusion, and the upstream regulatory pathways including the AMPK and MTORC1 pathways.
Abstract: Abstract Macroautophagy/autophagy is an evolutionally conserved catabolic process in which cytosolic contents, such as aggregated proteins, dysfunctional organelle, or invading pathogens, are sequestered by the double‐membrane structure termed autophagosome and delivered to lysosome for degradation. Over the past two decades, autophagy has been extensively studied, from the molecular mechanisms, biological functions, implications in various human diseases, to development of autophagy‐related therapeutics. This review will focus on the latest development of autophagy research, covering molecular mechanisms in control of autophagosome biogenesis and autophagosome–lysosome fusion, and the upstream regulatory pathways including the AMPK and MTORC1 pathways. We will also provide a systematic discussion on the implication of autophagy in various human diseases, including cancer, neurodegenerative disorders (Alzheimer disease, Parkinson disease, Huntington's disease, and Amyotrophic lateral sclerosis), metabolic diseases (obesity and diabetes), viral infection especially SARS‐Cov‐2 and COVID‐19, cardiovascular diseases (cardiac ischemia/reperfusion and cardiomyopathy), and aging. Finally, we will also summarize the development of pharmacological agents that have therapeutic potential for clinical applications via targeting the autophagy pathway. It is believed that decades of hard work on autophagy research is eventually to bring real and tangible benefits for improvement of human health and control of human diseases.

21 citations


Journal ArticleDOI
17 Feb 2022-MedComm
TL;DR: This review covers almost all SARS‐CoV‐2‐related topics extensively to deepen the understanding of the latest achievements and comprehensively review and summarize different aspects of prevention, diagnosis, and treatment of COVID‐19.
Abstract: Abstract Since the rapid onset of the COVID‐19 or SARS‐CoV‐2 pandemic in the world in 2019, extensive studies have been conducted to unveil the behavior and emission pattern of the virus in order to determine the best ways to diagnosis of virus and thereof formulate effective drugs or vaccines to combat the disease. The emergence of novel diagnostic and therapeutic techniques considering the multiplicity of reports from one side and contradictions in assessments from the other side necessitates instantaneous updates on the progress of clinical investigations. There is also growing public anxiety from time to time mutation of COVID‐19, as reflected in considerable mortality and transmission, respectively, from delta and Omicron variants. We comprehensively review and summarize different aspects of prevention, diagnosis, and treatment of COVID‐19. First, biological characteristics of COVID‐19 were explained from diagnosis standpoint. Thereafter, the preclinical animal models of COVID‐19 were discussed to frame the symptoms and clinical effects of COVID‐19 from patient to patient with treatment strategies and in‐silico/computational biology. Finally, the opportunities and challenges of nanoscience/nanotechnology in identification, diagnosis, and treatment of COVID‐19 were discussed. This review covers almost all SARS‐CoV‐2‐related topics extensively to deepen the understanding of the latest achievements (last updated on January 11, 2022).

20 citations


Journal ArticleDOI
09 Feb 2022-MedComm
TL;DR: Important challenges and future perspectives of cancer therapy using G‐ and GO‐based nanosystems have been highlighted, and the recent advancements are deliberated.
Abstract: Abstract Graphene‐based materials have shown immense pertinence for sensing/imaging, gene/drug delivery, cancer therapy/diagnosis, and tissue engineering/regenerative medicine. Indeed, the large surface area, ease of functionalization, high drug loading capacity, and reactive oxygen species induction potentials have rendered graphene‐ (G‐) and graphene oxide (GO)‐based (nano)structures promising candidates for cancer therapy applications. Various techniques namely liquid‐phase exfoliation, Hummer's method, chemical vapor deposition, chemically reduced GO, mechanical cleavage of graphite, arc discharge of graphite, and thermal fusion have been deployed for the production of G‐based materials. Additionally, important criteria such as biocompatibility, bio‐toxicity, dispersibility, immunological compatibility, and inflammatory reactions of G‐based structures need to be systematically assessed for additional clinical and biomedical appliances. Furthermore, surface properties (e.g., lateral dimension, charge, corona influence, surface structure, and oxygen content), concentration, detection strategies, and cell types are vital for anticancer activities of these structures. Notably, the efficient accumulation of anticancer drugs in tumor targets/tissues, controlled cellular uptake properties, tumor‐targeted drug release behavior, and selective toxicity toward the cells are crucial criteria that need to be met for developing future anticancer G‐based nanosystems. Herein, important challenges and future perspectives of cancer therapy using G‐ and GO‐based nanosystems have been highlighted, and the recent advancements are deliberated.

17 citations


Journal ArticleDOI
09 Apr 2022-MedComm
TL;DR: Using VOCs and VOIs as immunogens, it was found that the antigenicity of variants could be divided into three clusters, and each cluster showed similar antigenicity to different immunogens.
Abstract: Abstract The severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) variants, particularly those with multiple mutations in receptor‐binding domain (RBD), pose a critical challenge to the efficacy of coronavirus disease 2019 (COVID‐19) vaccines and therapeutic neutralizing monoclonal antibodies (mAbs). Omicron sublineages BA.1, BA.2, BA.3, as well as the recent emergence of C.1.2, B.1.630, B.1.640.1, and B.1.640.2, have multiple mutations in RBD and may lead to severe neutralizing antibody evasion. It is urgent to evaluate the antigenic change of the above seven variants against mAbs and sera from guinea pigs immunized with variants of concern (VOCs) (Alpha, Beta, Gamma, Delta, Omicron) and variants of interest (VOIs) (Lambda, Mu) immunogens. Only seven out of the 24 mAbs showed no reduction in neutralizing activity against BA.1, BA.2, and BA.3. However, among these seven mAbs, the neutralization activity of XGv337 and XGv338 against C.1.2, B.1.630, B.1.640.1, and B.1.640.2 were decreased. Therefore, only five neutralizing mAbs showed no significant change against these seven variants. Using VOCs and VOIs as immunogens, we found that the antigenicity of variants could be divided into three clusters, and each cluster showed similar antigenicity to different immunogens. Among them, D614G, B.1.640.1, and B.1.630 formed a cluster, C.1.2 and B.1.640.2 formed a cluster, and BA.1, BA.2, and BA.3 formed a cluster.

Journal ArticleDOI
17 Jan 2022-MedComm
TL;DR: The results suggested the gut microbiome of COVID‐19 patients was in a state of oxidative stress, and healthy gut microbiota may enhance antiviral defenses via butyrate metabolism, whereas the accumulation of opportunistic and inflammatory bacteria may exacerbate CO VID‐19 progression.
Abstract: Abstract Specific roles of gut microbes in COVID‐19 progression are critical. However, the circumstantial mechanism remains elusive. In this study, shotgun metagenomic or metatranscriptomic sequencing was performed on fecal samples collected from 13 COVID‐19 patients and controls. We analyzed the structure of gut microbiota, identified the characteristic bacteria, and selected biomarkers. Further, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) annotations were employed to correlate the taxon alterations and corresponding functions. The gut microbiota of COVID‐19 patients was characterized by the enrichment of opportunistic pathogens and depletion of commensals. The abundance of Bacteroides spp. displayed an inverse relationship with COVID‐19 severity, whereas Actinomyces oris, Escherichia coli, and Streptococcus parasanguini were positively correlated with disease severity. The genes encoding oxidoreductase were significantly enriched in gut microbiome of COVID‐19 group. KEGG annotation indicated that the expression of ABC transporter was upregulated, while the synthesis pathway of butyrate was aberrantly reduced. Furthermore, increased metabolism of lipopolysaccharide, polyketide sugar, sphingolipids, and neutral amino acids were found. These results suggested the gut microbiome of COVID‐19 patients was in a state of oxidative stress. Healthy gut microbiota may enhance antiviral defenses via butyrate metabolism, whereas the accumulation of opportunistic and inflammatory bacteria may exacerbate COVID‐19 progression.

Journal ArticleDOI
12 May 2022-MedComm
TL;DR: A review of the biological functions and important clinical therapeutic implications of lnRNAs and circRNAs in neuroblastoma focuses on providing rationale and relevant references for novel biomarkers for neuroblastomas diagnosis, prognosis, and treatment.
Abstract: Abstract It is well known that noncoding RNAs (ncRNAs) cannot encode proteins, but they can play important regulatory roles in tumors by combining with proteins, RNAs, and DNAs. As more and more studies reveal the important roles and underlying mechanisms of long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs) in cancer, their huge application potential in cancer therapy cannot be ignored. For example, lncRNAs can be involved in tumor‐related signal transduction pathways, cell cycle control, DNA damage, epigenetic regulation, and microRNA control. A group of studies confirmed that abnormal expression of lncRNAs can affect cancer progression. Furthermore, as covalently closed continuous circular ncRNAs, many recent studies have shown that circRNAs have regulatory effects and other important biological significances in cancer. Interestingly, circRNAs were found to have translational functions. This has greatly attracted people's attention to circRNAs research. In this review, we introduce the important roles of lncRNAs and circRNAs in some representative cancers, respectively. Furthermore, we focus on the biological functions and important clinical therapeutic implications of lnRNAs and circRNAs in neuroblastoma. Our review also focuses on providing rationale and relevant references for novel biomarkers for neuroblastoma diagnosis, prognosis, and treatment.

Journal ArticleDOI
01 Jun 2022-MedComm
TL;DR: Recent advances of chemokine systems in protumor and antitumor immune responses are summarized and the prevailing understanding of how the chemokines system operates in inflammatory diseases is discussed.
Abstract: Abstract Chemokines are a large family of small secreted proteins that have fundamental roles in organ development, normal physiology, and immune responses upon binding to their corresponding receptors. The primary functions of chemokines are to coordinate and recruit immune cells to and from tissues and to participate in regulating interactions between immune cells. In addition to the generally recognized antimicrobial immunity, the chemokine/chemokine receptor axis also exerts a tumorigenic function in many different cancer models and is involved in the formation of immunosuppressive and protective tumor microenvironment (TME), making them potential prognostic markers for various hematologic and solid tumors. In fact, apart from its vital role in tumors, almost all inflammatory diseases involve chemokines and their receptors in one way or another. Modulating the expression of chemokines and/or their corresponding receptors on tumor cells or immune cells provides the basis for the exploitation of new drugs for clinical evaluation in the treatment of related diseases. Here, we summarize recent advances of chemokine systems in protumor and antitumor immune responses and discuss the prevailing understanding of how the chemokine system operates in inflammatory diseases. In this review, we also emphatically highlight the complexity of the chemokine system and explore its potential to guide the treatment of cancer and inflammatory diseases.

Journal ArticleDOI
19 Aug 2022-MedComm
TL;DR: Evidence shows that neutrophils can protect the host against pathogens in multiple ways, including the formation and release of neutrophil extracellular traps (NETs), and researchers have discovered that several NET inhibitors, such as toll‐like receptor inhibitors and reactive oxygen species scavengers, can prevent uncontrolled NET development.
Abstract: Abstract Evidence shows that neutrophils can protect the host against pathogens in multiple ways, including the formation and release of neutrophil extracellular traps (NETs). NETs are web‐like structures composed of fibers, DNA, histones, and various neutrophil granule proteins. NETs can capture and kill pathogens, including bacteria, viruses, fungi, and protozoa. The process of NET formation is called NETosis. According to whether they depend on nicotinamide adenine dinucleotide phosphate (NADPH), NETosis can be divided into two categories: “suicidal” NETosis and “vital” NETosis. However, NET components, including neutrophil elastase, myeloperoxidase, and cell‐free DNA, cause a proinflammatory response and potentially severe diseases. Compelling evidence indicates a link between NETs and the pathogenesis of a number of diseases, including sepsis, systemic lupus erythematosus, rheumatoid arthritis, small‐vessel vasculitis, inflammatory bowel disease, cancer, COVID‐19, and others. Therefore, targeting the process and products of NETosis is critical for treating diseases linked with NETosis. Researchers have discovered that several NET inhibitors, such as toll‐like receptor inhibitors and reactive oxygen species scavengers, can prevent uncontrolled NET development. This review summarizes the mechanism of NETosis, the receptors associated with NETosis, the pathology of NETosis‐induced diseases, and NETosis‐targeted therapy.

Journal ArticleDOI
01 Mar 2022-MedComm
TL;DR: Findings uncover a role for SHP2 in NET release and subsequent cell death known as NETosis in the progression of psoriasis and suggest that SHP 2 may be a promising therapeutic target for psoriatic patients.
Abstract: Abstract Psoriasis is a chronic inflammatory skin disease, often accompanied by increased infiltration of immune cells, especially neutrophils. However, the detailed mechanism of the neutrophil function in psoriasis progression remains unclear. Here, we found that both Src homology‐2 domain‐containing protein tyrosine phosphatase‐2 (SHP2) and neutrophils were highly correlated to developing psoriasis by single‐cell ribonucleic acid (RNA) sequencing and experiment verification. The deficiency of SHP2 in neutrophils significantly alleviated psoriasis‐like phenotype in an imiquimod‐induced murine model. Interestingly, high levels of neutrophil extracellular traps (NETs) were produced in the inflamed lesions of psoriatic patients. In addition, imiquimod‐induced psoriasis‐like symptoms were remarkably ameliorated in peptidyl arginine deiminase 4 (PAD4) knockout mice, which cannot form NETs. Mechanistically, RNA‐seq analysis revealed that SHP2 promoted the formation of NETs in neutrophils via the ERK5 pathway. Functionally, this mechanism resulted in the infiltration of pro‐inflammatory cytokines such as TNF‐α, IL‐1β, IL‐6, IL‐17A, and CXCL‐15, which enhances the inflammatory response in skin lesions and reinforces the cross‐talk between neutrophils and keratinocytes, ultimately aggravating psoriasis. Our findings uncover a role for SHP2 in NET release and subsequent cell death known as NETosis in the progression of psoriasis and suggest that SHP2 may be a promising therapeutic target for psoriasis.

Journal ArticleDOI
16 Aug 2022-MedComm
TL;DR: This review focuses on the Omicron variant's origin, transmission, main biological features, subvariants, mutations, immune escape, vaccination, and detection methods, and discusses the appropriate preventive and therapeutic measures that should be taken.
Abstract: Abstract Since the start of the coronavirus disease 2019 (COVID‐19) pandemic, new variants of severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) have emerged, accelerating the spread of the virus. Omicron was defined by the World Health Organization in November 2021 as the fifth “variant of concern” after Alpha, Beta, Gamma, and Delta. In recent months, Omicron has become the main epidemic strain. Studies have shown that Omicron carries more mutations than Alpha, Beta, Gamma, Delta, and wild‐type, facilitating immune escape and accelerating its transmission. This review focuses on the Omicron variant's origin, transmission, main biological features, subvariants, mutations, immune escape, vaccination, and detection methods. We also discuss the appropriate preventive and therapeutic measures that should be taken to address the new challenges posed by the Omicron variant. This review is valuable to guide the surveillance, prevention, and development of vaccines and other therapies for Omicron variants. It is desirable to develop a more efficient vaccine against the Omicron variant and take more effective measures to constrain the spread of the epidemic and promote public health.

Journal ArticleDOI
09 Aug 2022-MedComm
TL;DR: Current understanding of the hallmarks of COVID‐19 metabolism is summarized and remodeling of host metabolism creates metabolic vulnerability of SARS‐CoV‐2 replication, which could be explored to uncover new therapeutic targets.
Abstract: Abstract Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) dysregulates antiviral signaling, immune response, and cell metabolism in human body. Viral genome and proteins hijack host metabolic network to support viral biogenesis and propagation. However, the regulatory mechanism of SARS‐CoV‐2‐induced metabolic dysfunction has not been elucidated until recently. Multiomic studies of coronavirus disease 2019 (COVID‐19) revealed an intensive interaction between host metabolic regulators and viral proteins. SARS‐CoV‐2 deregulated cellular metabolism in blood, intestine, liver, pancreas, fat, and immune cells. Host metabolism supported almost every stage of viral lifecycle. Strikingly, viral proteins were found to interact with metabolic enzymes in different cellular compartments. Biochemical and genetic assays also identified key regulatory nodes and metabolic dependencies of viral replication. Of note, cholesterol metabolism, lipid metabolism, and glucose metabolism are broadly involved in viral lifecycle. Here, we summarized the current understanding of the hallmarks of COVID‐19 metabolism. SARS‐CoV‐2 infection remodels host cell metabolism, which in turn modulates viral biogenesis and replication. Remodeling of host metabolism creates metabolic vulnerability of SARS‐CoV‐2 replication, which could be explored to uncover new therapeutic targets. The efficacy of metabolic inhibitors against COVID‐19 is under investigation in several clinical trials. Ultimately, the knowledge of SARS‐CoV‐2‐induced metabolic reprogramming would accelerate drug repurposing or screening to combat the COVID‐19 pandemic.

Journal ArticleDOI
01 Aug 2022-MedComm
TL;DR: In this paper , the major inflammatory pathways in the pathogenesis of COVID-19, including induction, function, and downstream signaling, as well as existing and potential interventions targeting these cytokines or related signaling pathways are discussed.
Abstract: The 2019 coronavirus disease (COVID-19) pandemic has become a global crisis. In the immunopathogenesis of COVID-19, SARS-CoV-2 infection induces an excessive inflammatory response in patients, causing an inflammatory cytokine storm in severe cases. Cytokine storm leads to acute respiratory distress syndrome, pulmonary and other multiorgan failure, which is an important cause of COVID-19 progression and even death. Among them, activation of inflammatory pathways is a major factor in generating cytokine storms and causing dysregulated immune responses, which is closely related to the severity of viral infection. Therefore, elucidation of the inflammatory signaling pathway of SARS-CoV-2 is important in providing otential therapeutic targets and treatment strategies against COVID-19. Here, we discuss the major inflammatory pathways in the pathogenesis of COVID-19, including induction, function, and downstream signaling, as well as existing and potential interventions targeting these cytokines or related signaling pathways. We believe that a comprehensive understanding of the regulatory pathways of COVID-19 immune dysregulation and inflammation will help develop better clinical therapy strategies to effectively control inflammatory diseases, such as COVID-19.

Journal ArticleDOI
10 Sep 2022-MedComm
TL;DR: Cryo‐electron microscopy technology revealed that the extracellular loop2 of GPR17 occupied the orthosteric binding pocket to promote its self‐activation and may facilitate the pharmacological intervention for acute/chronic CNS injury.
Abstract: Abstract GPR17 is a class A orphan G protein‐coupled receptor (GPCR) expressed in neurons and oligodendrocyte progenitors of the central nervous system (CNS). The signalling of GPR17 occurs through the heterotrimeric Gi, but its activation mechanism is unclear. Here, we employed cryo‐electron microscopy (cryo‐EM) technology to elucidate the structure of activated GPR17‐Gi complex. The 3.02 Å resolution structure, together with mutagenesis studies, revealed that the extracellular loop2 of GPR17 occupied the orthosteric binding pocket to promote its self‐activation. The active GPR17 carried several typical microswitches like other class A GPCRs. Moreover, the Gi interacted with the key residues of transmembrane helix 3 (TM3), the amphipathic helix 8 (Helix8), and intracellular loops 3 (ICL3) in GPR17 to engage in the receptor core. In summary, our results highlight the activation mechanism of GPR17 from the structural basis. Elucidating the structural and activation mechanism of GPR17 may facilitate the pharmacological intervention for acute/chronic CNS injury.

Journal ArticleDOI
13 Oct 2022-MedComm
TL;DR: To better promote the development of small molecule inhibitor targeting cancers, a comprehensively reviewed small molecule inhibitors involved in all the approved agents and pivotal drug candidates in clinical trials arranged by the signaling pathways and the classification ofsmall molecule inhibitors.
Abstract: Abstract Compared with traditional therapies, targeted therapy has merits in selectivity, efficacy, and tolerability. Small molecule inhibitors are one of the primary targeted therapies for cancer. Due to their advantages in a wide range of targets, convenient medication, and the ability to penetrate into the central nervous system, many efforts have been devoted to developing more small molecule inhibitors. To date, 88 small molecule inhibitors have been approved by the United States Food and Drug Administration to treat cancers. Despite remarkable progress, small molecule inhibitors in cancer treatment still face many obstacles, such as low response rate, short duration of response, toxicity, biomarkers, and resistance. To better promote the development of small molecule inhibitors targeting cancers, we comprehensively reviewed small molecule inhibitors involved in all the approved agents and pivotal drug candidates in clinical trials arranged by the signaling pathways and the classification of small molecule inhibitors. We discussed lessons learned from the development of these agents, the proper strategies to overcome resistance arising from different mechanisms, and combination therapies concerned with small molecule inhibitors. Through our review, we hoped to provide insights and perspectives for the research and development of small molecule inhibitors in cancer treatment.

Journal ArticleDOI
17 Jun 2022-MedComm
TL;DR: An improved way to extract ctDNA, reduce background contamination, and build a whole‐genome bisulfite sequencing (WGBS) library from different stages of breast cancer is reported, identifying high specificity and sensitivity breast cancer‐specific methylation CpG site biomarkers.
Abstract: Abstract The changes in circulating tumor DNA (ctDNA) methylation are believed to be early events in breast cancer initiation, which makes them suitable as promising biomarkers for early diagnosis. However, applying ctDNA in breast cancer early diagnosis remains highly challenging due to the contamination of background DNA from blood and low DNA methylation signals. Here, we report an improved way to extract ctDNA, reduce background contamination, and build a whole‐genome bisulfite sequencing (WGBS) library from different stages of breast cancer. We first compared the DNA methylation data of 74 breast cancer patients with those of seven normal controls to screen candidate methylation CpG site biomarkers for breast cancer diagnosis. The obtained 26 candidate ctDNA methylation biomarkers produced high accuracy in breast cancer patients (area under the curve [AUC] = 0.889; sensitivity: 100%; specificity: 75%). Furthermore, we revealed potential ctDNA methylated CpG sites for detecting early‐stage breast cancer (AUC = 0.783; sensitivity: 93.44%; specificity: 50%). In addition, different subtypes of breast cancer could be well distinguished by the ctDNA methylome, which was obtained through our improved ctDNA‐WGBS method. Overall, we identified high specificity and sensitivity breast cancer‐specific methylation CpG site biomarkers, and they will be expected to have the potential to be translated to clinical practice.

Journal ArticleDOI
18 Aug 2022-MedComm
TL;DR: Different nanocarriers for controlled drug release and their routes of administration have been discussed in detail, especially for cancer treatment, with special emphasis on the design of drug delivery vehicles for sustained release and specific application methods for targeted delivery to the affected areas.
Abstract: Abstract The higher prevalence of cancer is related to high rates of mortality and morbidity worldwide. By virtue of the properties of matter at the nanoscale, nanomedicine is proven to be a powerful tool to develop innovative drug carriers with greater efficacies and fewer side effects than conventional therapies. In this review, different nanocarriers for controlled drug release and their routes of administration have been discussed in detail, especially for cancer treatment. Special emphasis has been given on the design of drug delivery vehicles for sustained release and specific application methods for targeted delivery to the affected areas. Different polymeric vehicles designed for the delivery of chemotherapeutics have been discussed, including graft copolymers, liposomes, hydrogels, dendrimers, micelles, and nanoparticles. Furthermore, the effect of dimensional properties on chemotherapy is vividly described. Another integral section of the review focuses on the modes of administration of nanomedicines and emerging therapies, such as photothermal, photodynamic, immunotherapy, chemodynamic, and gas therapy, for cancer treatment. The properties, therapeutic value, advantages, and limitations of these nanomedicines are highlighted, with a focus on their increased performance versus conventional molecular anticancer therapies.

Journal ArticleDOI
21 Jul 2022-MedComm
TL;DR: This review focused on the fast antidepressant treatment and clarified the safety, tolerability, and efficacy of ketamine and its metabolites for the MDD treatment, along with a review of the potential pharmacological mechanisms, research challenges, and future clinical prospects.
Abstract: Abstract Major depressive disorder (MDD) is a highly prevalent and disabling disorder. Despite the many hypotheses proposed to understand the molecular pathophysiology of depression, it is still unclear. Current treatments for depression are inadequate for many individuals, because of limited effectiveness, delayed efficacy (usually two weeks), and side effects. Consequently, novel drugs with increased speed of action and effectiveness are required. Ketamine has shown to have rapid, reliable, and long‐lasting antidepressant effects in treatment‐resistant MDD patients and represent a breakthrough therapy for patients with MDD; however, concerns regarding its efficacy, potential misuse, and side effects remain. In this review, we aimed to summarize molecular mechanisms and pharmacological treatments for depression. We focused on the fast antidepressant treatment and clarified the safety, tolerability, and efficacy of ketamine and its metabolites for the MDD treatment, along with a review of the potential pharmacological mechanisms, research challenges, and future clinical prospects.

Journal ArticleDOI
25 Aug 2022-MedComm
TL;DR: The clinical value of mRNA vaccines as potent candidates for therapeutic treatment and clinical progress in the treatment of cancer and coronavirus disease 2019 are highlighted and data suggest that mRNA vaccines, with several prominent advantages, have achieved encouraging results and increasing attention.
Abstract: Abstract Messenger ribonucleic acid (mRNA) vaccines made their successful public debut in the effort against the COVID‐19 outbreak starting in late 2019, although the history of mRNA vaccines can be traced back decades. This review provides an overview to discuss the historical course and present situation of mRNA vaccine development in addition to some basic concepts that underly mRNA vaccines. We discuss the general preparation and manufacturing of mRNA vaccines and also discuss the scientific advances in the in vivo delivery system and evaluate popular approaches (i.e., lipid nanoparticle and protamine) in detail. Next, we highlight the clinical value of mRNA vaccines as potent candidates for therapeutic treatment and discuss clinical progress in the treatment of cancer and coronavirus disease 2019. Data suggest that mRNA vaccines, with several prominent advantages, have achieved encouraging results and increasing attention due to tremendous potential in disease management. Finally, we suggest some potential directions worthy of further investigation and optimization. In addition to basic research, studies that help to facilitate storage and transportation will be indispensable for practical applications.

Journal ArticleDOI
22 Apr 2022-MedComm
TL;DR: Finding that loss of Trp53/Rb1 in Ctsk‐expressing cells significantly elevated Yes‐associated protein (YAP) expression and activity provides proof of principle that inhibition of YAP activity may be a potential strategy for osteosarcoma treatment.
Abstract: Abstract Glucose metabolism reprogramming is a critical factor in the progression of multiple cancers and is directly regulated by many tumor suppressors. However, how glucose metabolism regulates osteosarcoma development and progression is largely unknown. Cathepsin K (Ctsk) has been reported to express in chondroprogenitor cells and stem cells besides osteoclasts. Moreover, mutations in the tumor suppressors transformation‐related protein 53 (Trp53) and retinoblastoma protein (Rb1) are evident in approximately 50%–70% of human osteosarcoma. To understand how deletion of Trp53 and Rb1 in Ctsk‐expressing cells drives tumorigenesis, we generated the Ctsk‐Cre;Trp53f/f/Rb1f/f mouse model. Our data revealed that those mice developed osteosarcoma without formation of tumor in osteoclast lineage. The level of cortical bone destruction was gradually increased in parallel to the osteosarcoma progression rate. Through mechanistic studies, we found that loss of Trp53/Rb1 in Ctsk‐expressing cells significantly elevated Yes‐associated protein (YAP) expression and activity. YAP/TEAD1 complex binds to the glucose transporter 1 (Glut1) promoter to upregulate Glut1 expression. Upregulated Glut1 expression led to overactive glucose metabolism, increasing osteosarcoma progression. Ablation of YAP signaling inhibited energy metabolism and delayed osteosarcoma progression in Ctsk‐Cre;Trp53f/f/Rb1f/f mice. Collectively, these findings provide proof of principle that inhibition of YAP activity may be a potential strategy for osteosarcoma treatment.

Journal ArticleDOI
01 Mar 2022-MedComm
TL;DR: This is the first time to put forward the theory of Yin‐Yang balance to understand trained immunity, and it is envisioned that more efforts will be focused on developing novel immunotherapies targeting trained immunity in the coming years.
Abstract: Abstract Traditionally, immune memory is regarded as an exclusive hallmark of adaptive immunity. However, a growing body of evidence suggesting that innate immune cells show adaptive characteristics has challenged this dogma. In the past decade, trained immunity, a de facto innate immune memory, has been defined as a long‐term functional reprogramming of cells of the innate immune system: the reprogramming is evoked by endogenous or exogenous insults, the cells return to a nonactivated state and subsequently show altered inflammatory responses against a second challenge. Trained immunity became regarded as a mechanism selected in evolution to protect against infection; however, a maladaptive effect might result in hyperinflammation. This dual effect is consistent with the Yin‐Yang theory in traditional Chinese philosophy, in which Yang represents active, positive, and aggressive factors, whereas Yin represents passive, negative, and inhibitory factors. In this review, we give a brief overview of history and latest progress about trained immunity, including experimental models, inductors, molecular mechanisms, clinical application and so on. Moreover, this is the first time to put forward the theory of Yin‐Yang balance to understand trained immunity. We envision that more efforts will be focused on developing novel immunotherapies targeting trained immunity in the coming years.

Journal ArticleDOI
03 Nov 2022-MedComm
TL;DR: In this article , the authors analyzed 303 small-molecule protein phosphorylation kinase inhibitors (PKIs) registered and participated in clinical research obtained in a database named Protein Kinase Inhibitor Database (PKIDB), including 68 drugs approved by the Food and Drug Administration of the United States.
Abstract: Abstract Protein phosphorylation is an important post‐transcriptional modification involving an extremely wide range of intracellular signaling transduction pathways, making it an important therapeutic target for disease intervention. At present, numerous drugs targeting protein phosphorylation have been developed for the treatment of various diseases including malignant tumors, neurological diseases, infectious diseases, and immune diseases. In this review article, we analyzed 303 small‐molecule protein phosphorylation kinase inhibitors (PKIs) registered and participated in clinical research obtained in a database named Protein Kinase Inhibitor Database (PKIDB), including 68 drugs approved by the Food and Drug Administration of the United States. Based on previous classifications of kinases, we divided these human protein phosphorylation kinases into eight groups and nearly 50 families, and delineated their main regulatory pathways, upstream and downstream targets. These groups include: protein kinase A, G, and C (AGC) and receptor guanylate cyclase (RGC) group, calmodulin‐dependent protein kinase (CaMK) group, CMGC [Cyclin‐dependent kinases (CDKs), Mitogen‐activated protein kinases (MAPKs), Glycogen synthase kinases (GSKs), and Cdc2‐like kinases (CLKs)] group, sterile (STE)‐MAPKs group, tyrosine kinases (TK) group, tyrosine kinase‐like (TKL) group, atypical group, and other groups. Different groups and families of inhibitors stimulate or inhibit others, forming an intricate molecular signaling regulatory network. This review takes newly developed new PKIs as breakthrough point, aiming to clarify the regulatory network and relationship of each pathway, as well as their roles in disease intervention, and provide a direction for future drug development.

Journal ArticleDOI
01 Mar 2022-MedComm
TL;DR: In this paper , a generalized susceptible-infected-removed (SIR) model and a corresponding parameter identification procedure were used to simulate 13 epidemic waves for Ukraine and six pandemic waves for the whole world.
Abstract: Dear editor, The sharp increase in the number of new COVID19 cases in late 2021 and early 2022 associated with the SARS-CoV-2 omicron (B.1.1.529) strain made it necessary to update the forecasts. Comparative analysis yielded some preliminary predictions of time durations when the maximal number of new cases are expected.1 To estimate the duration of new pandemic waves and the number of infectious persons, different versions of susceptibleinfected-removed (SIR) model can be applied (see e.g.,2–4). In particular, generalized SIR model and a corresponding parameter identification procedure4 were used to simulate 13 epidemic waves for Ukraine and six pandemic waves for the whole world. Thus, we can hope for an accurate forecast for the omicron waves (14th in Ukraine and seventh in the world), to which this study is devoted. We will use the dataset regarding the accumulated numbers of laboratory-confirmed COVID-19 cases Vj in Ukraine and the whole world from the COVID-19 Data Repository by the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University (JHU)5 (Tables S1 and S2). To simulate the 14th wave in Ukraine and seventh wave in the world, we will use the datasets, corresponding to the period January 22 to February 4, 2022. Other values of Vj and corresponding moments of time tj (measured in days) will be used to control the accuracy of calculations only. The generalized SIR model relates the number of susceptible S(t), infectious I(t), and removed persons R(t) versus time t for a particular epidemic wave i.4 The exact solution of the set of nonlinear differential equations uses the function V(t) = I(t) + R(t), corresponding to the number of victims or the cumulative laboratory-confirmed number of cases (Supporting Methods4). Its derivative dV/dt yields the estimation of the average daily number of new cases. When the registered number of victims Vj is a random realization of its theoretical dependence, the exact

Journal ArticleDOI
05 Oct 2022-MedComm
TL;DR: An overview of the regulating networks and their immune interactions involved in CSC development is provided and the update on the development of CSC‐directed therapeutics is addressed, with a special focus on those with application approval or under clinical evaluation.
Abstract: Abstract Cancer stem cells (CSCs) are defined as a subpopulation of malignant tumor cells with selective capacities for tumor initiation, self‐renewal, metastasis, and unlimited growth into bulks, which are believed as a major cause of progressive tumor phenotypes, including recurrence, metastasis, and treatment failure. A number of signaling pathways are involved in the maintenance of stem cell properties and survival of CSCs, including well‐established intrinsic pathways, such as the Notch, Wnt, and Hedgehog signaling, and extrinsic pathways, such as the vascular microenvironment and tumor‐associated immune cells. There is also intricate crosstalk between these signal cascades and other oncogenic pathways. Thus, targeting pathway molecules that regulate CSCs provides a new option for the treatment of therapy‐resistant or ‐refractory tumors. These treatments include small molecule inhibitors, monoclonal antibodies that target key signaling in CSCs, as well as CSC‐directed immunotherapies that harness the immune systems to target CSCs. This review aims to provide an overview of the regulating networks and their immune interactions involved in CSC development. We also address the update on the development of CSC‐directed therapeutics, with a special focus on those with application approval or under clinical evaluation.