Pathological Features of Kaposi's Sarcoma-Associated Herpesvirus Infection

The functions of herpesvirus shuttling proteins in the virus lifecycle

During viral infection, the transport of various proteins between the nucleus and cytoplasm plays an important role in the viral lifecycle. Shuttling proteins are key factors in the transmission of nucleocytoplasmic information within cells and usually contain nuclear localization signals and nuclear export signals to mediate correct positioning for themselves and other proteins. The nucleocytoplasmic transport process is carried out through the nuclear pore complex on the nuclear envelope and is mediated by specific protein carriers. The viral proteins that function through nucleocytoplasmic shuttling in herpesviruses have gradually been identified as research advances. This article provides an overview of how shuttling proteins utilize nucleocytoplasmic shuttling signals and nuclear transport receptors for nucleocytoplasmic transport, as well as discusses how herpesvirus shuttling proteins enhance the effective infection of viruses by affecting their lifecycle and participating in innate immunity, this review provides a reference for understanding the pathogenesis of herpesvirus infection and determining new antiviral strategies.

Impact of valganciclovir therapy on severe IRIS-Kaposi Sarcoma mortality: An open-label, parallel, randomized controlled trial

INTRODUCTION

High HHV-8 viral load (VL) in Kaposi Sarcoma (KS) has been associated with Severe Immune Reconstitution Inflammatory Syndrome (Severe-IRIS-KS), which can occur after initiating cART, and leads to high mortality, particularly in patients with pulmonary involvement. We investigate if valganciclovir (as an anti-HHV-8 agent) initiated before cART reduces the mortality associated with Severe-IRIS-KS and the incidence of Severe-IRIS-KS.

METHODS

Open-label parallel-group randomized clinical trial in AIDS cART naïve patients with disseminated KS (DKS) as defined by at least two of the following: pulmonary, lymph-node, or gastrointestinal involvement, lymphedema, or ≥30 skin lesions. In the experimental group (EG), patients received valganciclovir 900 mg BID four weeks before cART and continued until week 48; in the control group (CG), cART was initiated on week 0. Non-severe-IRIS-KS was defined as: an increase in the number of lesions plus a decrease of ≥one log10 HIV-VL, or an increase of ≥50cells/mm3 or ≥2-fold in baseline CD4+cells. Severe-IRIS-KS was defined as abrupt clinical worsening of KS lesions and/or fever after ruling out another infection following cART initiation, and at least three of the following: thrombocytopenia, anemia, hyponatremia, or hypoalbuminemia.

RESULTS

40 patients were randomized and 37 completed the study. In the ITT analysis, at 48 weeks, total mortality was the same in both groups (3/20), severe-IRIS-KS attributable mortality was 0/20 in the EG, compared with 3/20 in the CG (p = 0.09), similar to the per-protocol analysis: 0/18 in the EG, and 3/19 in the control group (p = 0.09). The crude incidence rate of severe-IRIS-KS was four patients developed a total of 12 episodes of Severe-IRIS-KS in the CG and two patients developed one episode each in the EG. Mortality in patients with pulmonary KS was nil in the EG (0/5) compared with 3/4 in the CG (P = 0.048). No difference was found between groups in the number of non-S-IRIS-KS events. Among survivors at week 48, 82% achieved >80% remission.

CONCLUSIONS

Although mortality attributable to KS was lower in the EG the difference was not statistically significant.

Network Pharmacology and Molecular Docking Analysis on Molecular Targets and Mechanisms of "Chuanxiong Rhizoma: Radix Salviae miltiorrhizae" Herb Couples in the Treatment of Preeclampsia

Objective

The aim of the study is to explore the molecular mechanism of activating blood circulation and dispersing stasis herbs in the treatment of pre-eclampsia with Chuanxiong Rhizoma-Radix Salvia miltiorrhiza.

Methods

The chemical composition and targets of Chuanxiong Rhizoma-Radix Salvia miltiorrhiza were retrieved from the TCMSP database, and a PPI network was constructed for common genes. Subsequently, a graph of the "active component-target-action pathway" was plotted by Cytoscape 3.7.2 and a KEGG pathway enrichment was performed using the R language cluster profiler package. Molecular docking was conducted between the top five PPI targets of Chuanxiong Rhizoma-Radix Salvia miltiorrhiza.

Results

According to network pharmacology, there were 32 target genes, 60 active components, and 59 pathways in Chuanxiong Rhizoma-Radix Salvia miltiorrhiza, and its most evident effects were exerted on G-protein-coupled amine receptors and the neuroactive ligand-receptor interaction signaling pathway. Molecular docking indicated that the target protein had a good binding ability with the drugs.

Conclusion

Chuanxiong Rhizoma-Radix Salvia miltiorrhiza have therapeutic effects in pre-eclampsia, as confirmed by the results of molecular biology analysis. Thus, the Chuanxiong Rhizoma-Radix Salvia miltiorrhiza regimen provides a basis for the treatment of pre-eclampsia using traditional Chinese medicine.

Oncopreventive and oncotherapeutic potential of licorice triterpenoid compound glycyrrhizin and its derivatives: Molecular insights

Licorice (Glycyrrhiza glabra) is a well-known natural herb used to treat different ailments since ancient times. Glycyrrhizin (GL), which is the primary triterpenoid compound of licorice extract, has been known to have broad-spectrum pharmacological effects. GL is cleaved into glucuronide and the aglycone, glycyrrhetinic acid (GA), which exists in two stereoisomeric forms: 18α- and 18β-GA. It is well documented that GL and GA have great potential as anti-inflammatory, anticancer, antiviral, anti-diabetic, antioxidant, and hepatoprotective agents. Studies undertaken during the coronavirus disease 2019 pandemic suggest that GL is effective at inhibiting the viral replication of severe acute respiratory syndrome coronavirus 2. The anticancer effects of GL and GA involve modulating various signaling pathways, such as the phosphatase and tensin homolog/phosphatidylinositol 3-kinase/protein kinase B pathway, the mitogen-activated protein kinase, and the mammalian target of rapamycin/signal transducer and activator of transcription 3, which are mainly involved in regulating cancer cell death, oxidative stress, and inflammation. The potential of GL and GA in preventing cancer development and suppressing the growth and invasion of different cancer types has been reviewed in this paper. This review also provides molecular insights on the mechanism of action for the oncopreventive and oncotherapeutic effects of GL and its derivative, GA, which could help develop more specific forms of these agents for clinical use.

Cellulitis in patients with chronic lower-limb lymphedema due to HIV-related Kaposi sarcoma

OBJECTIVE

Chronic Lower Limb Lymphedema (CL-LL) secondary to Kaposi sarcoma (KS) has not been recognized as a risk factor for cellulitis. The aim was to describe the clinical spectrum and use of antimicrobial prophylaxis in patients with cellulitis and CL-LL due to KS.

METHODS

HIV patients with KS, CL-LL, and at least one episode of cellulitis seen at the AIDS Cancer Clinic at INCan in Mexico from 2004 to 2019 were included. Demographic and clinical data were obtained from medical records.

RESULTS

Thirty-nine men all with CL-LL were included. Clinical factors associated with cellulitis were groin and/or lymph-node KS infiltration (69.2%), onychomycosis and/or tinea pedis (44.7%), ulcerated lesions (38.4%), and obesity (2.5%). Eighteen (46.1%) were hospitalized in the first episode and eight (20.5%) in recurrence. Six (25.3%) died, two of toxic shock syndrome (TSS), and one of septic shock. Fourteen (35.8%) had at least one recurrent episode of cellulitis. Twenty-five (64.1%) received prophylaxis. Patients without prophylaxis had significantly more unfavorable outcomes (hospitalization and recurrences) than those with prophylaxis.

CONCLUSIONS

CL-LL due to KS is a risk factor for cellulitis and severe complications in patients with a long life expectancy. Antimicrobial prophylaxis needs to be explored as it could prevent complications.

Latently KSHV-Infected Cells Promote Further Establishment of Latency upon Superinfection with KSHV

Kaposi’s sarcoma-associated herpesvirus (KSHV) is a cancer-related virus which engages in two forms of infection: latent and lytic. Latent infection allows the virus to establish long-term persistent infection, whereas the lytic cycle is needed for the maintenance of the viral reservoir and for virus spread. By using recombinant KSHV viruses encoding mNeonGreen and mCherry fluorescent proteins, we show that various cell types that are latently-infected with KSHV can be superinfected, and that the new incoming viruses establish latent infection. Moreover, we show that latency establishment is enhanced in superinfected cells compared to primary infected ones. Further analysis revealed that cells that ectopically express the major latency protein of KSHV, LANA-1, prior to and during infection exhibit enhanced establishment of latency, but not cells expressing LANA-1 fragments. This observation supports the notion that the expression level of LANA-1 following infection determines the efficiency of latency establishment and avoids loss of viral genomes. These findings imply that a host can be infected with more than a single viral genome and that superinfection may support the maintenance of long-term latency.

Cell Fusion and Syncytium Formation in Betaherpesvirus Infection

Cell–cell fusion is a fundamental and complex process that occurs during reproduction, organ and tissue growth, cancer metastasis, immune response, and infection. All enveloped viruses express one or more proteins that drive the fusion of the viral envelope with cellular membranes. The same proteins can mediate the fusion of the plasma membranes of adjacent cells, leading to the formation of multinucleated syncytia. While cell–cell fusion triggered by alpha- and gammaherpesviruses is well-studied, much less is known about the fusogenic potential of betaherpesviruses such as human cytomegalovirus (HCMV) and human herpesviruses 6 and 7 (HHV-6 and HHV-7). These are slow-growing viruses that are highly prevalent in the human population and associated with several diseases, particularly in individuals with an immature or impaired immune system such as fetuses and transplant recipients. While HHV-6 and HHV-7 are strictly lymphotropic, HCMV infects a very broad range of cell types including epithelial, endothelial, mesenchymal, and myeloid cells. Syncytia have been observed occasionally for all three betaherpesviruses, both during in vitro and in vivo infection. Since cell–cell fusion may allow efficient spread to neighboring cells without exposure to neutralizing antibodies and other host immune factors, viral-induced syncytia may be important for viral dissemination, long-term persistence, and pathogenicity. In this review, we provide an overview of the viral and cellular factors and mechanisms identified so far in the process of cell–cell fusion induced by betaherpesviruses and discuss the possible consequences for cellular dysfunction and pathogenesis.

Pulmonary involvement in acquired immunodeficiency syndrome-associated Kaposi's sarcoma: a descriptive analysis of thin-section manifestations in 29 patients

Background

Acquired immunodeficiency syndrome-associated Kaposi's sarcoma (AIDS-KS) was the first malignant neoplasm to be described as being related to AIDS. The lungs are the most common visceral site of AIDS-KS. This study aimed to analyze the computed tomography (CT) manifestations of pulmonary involvement in AIDS-KS.

Methods

Twenty-nine male patients were enrolled in this retrospective study. Imaging evaluation parameters included lesion distribution, the flame sign, interlobular septal thickening, peribronchovascular interstitium thickening, ground-glass opacity (GGO), dilated blood vessels in lesions, and pleural effusion.

Results

A peribronchovascular distribution was observed in all patients, predominantly in the lower lobes. Of the patients, 58.62% (17/29) exhibited the flame sign, 75.86% (22/29) had interlobular septal thickening, 72.41% (21/29) had peribronchovascular interstitium thickening, 82.76% (24/29) had GGO, and 34.48% (10/29) had pleural effusion. Enlarged lymph nodes with a short-axis diameter >1.0 cm were found in 41.38% (12/29) of the patients. Of the 12 patients who underwent contrast-enhanced CT (CECT), 90.91% (11/12) had dilated blood vessels, and nodules, consolidations, and lymph nodes were observed to be strongly enhanced. Intrapulmonary lesions decreased in size or number after appropriate treatment during follow-up.

Conclusions

Common CT manifestations of pulmonary AIDS-KS include the flame sign, peribronchovascular distribution, peribronchovascular interstitium thickening, interlobular septa thickening, GGO, dilated blood vessel, and strong enhancement of nodules, consolidations, and lymph nodes. It is helpful to follow up the therapeutic effect of pulmonary AIDS-KS by chest CT.

An Introduction to Virus Infections and Human Cancer

Approximately, 1.4 million virus-induced cancers occur annually, representing roughly 10% of the worldwide cancer burden, with the majority (> 85%) occurring in the lower- and middle-income countries. The viruses associated with the greatest number of cancer cases are human papillomaviruses (HPVs), which cause cervical cancer and several other epithelial malignancies, and hepatitis viruses HBV and HCV, which are responsible for the majority of hepatocellular cancer. Other oncoviruses include Epstein-Barr virus (EBV), Kaposi's sarcoma herpesvirus (KSHV), human T-cell leukemia virus (HTLV-I), and Merkel cell polyoma virus (MCPyV). These oncoviruses include various classes of DNA and RNA viruses and induce cancer by a variety of mechanisms. However, cancers develop in a minority of infected individuals and almost always after chronic infection of many year's duration. Identification of the oncoviruses has provided critical insights in human carcinogenesis and led to several interventions that may reduce the risk of developing the tumors they induce. These interventions include preventive vaccines against HBV and HPV, screening for persistent HPV and HCV infections, antivirals for the treatment of chronic HBV and HCV infection, and screening the blood supply for the presence of HBV and HCV. Further efforts to identify additional oncogenic viruses in human cancers and new insights into etiology and pathogenesis of virally induced cancers would likely lead to new approaches for prophylactic and therapeutic interventions.

Safety and efficacy of anti-il6-receptor tocilizumab use in severe and critical patients affected by coronavirus disease 2019: A comparative analysis

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Cytokine release syndrome seems to play a pivotal role in COVID-19 pathogenesis.

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Tocilizumab is one of the most promising drugs for COVID-19.

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Tocilizumab halved the mortality in critical patients compared to standard of care.

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A transient respiratory function worsening is observed soon after administration.

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Severe infective complications are more common than in rheumatologic setting.

Background

As the novel SARS-CoV-2 pandemic occurred, no specific treatment was yet available. Inflammatory response secondary to viral infection might be the driver of severe diseases. We report the safety and efficacy (in terms of overall survival and hospital discharge) of the anti-IL6 tocilizumab (TCZ) in subjects with COVID-19.

Methods

This retrospective, single-center analysis included all the patients consecutively admitted to our Hospital with severe or critical COVID-19 who started TCZ treatment from March 13th to April 03rd, 2020. A 1:2 matching to patients not treated with TCZ was performed according to age, sex, severity of disease, P/F, Charlson Comorbidity Index and length of time between symptoms onset and hospital admittance. Descriptive statistics and non-parametric tests to compare the groups were applied. Kaplan Meier probability curves and Cox regression models for survival, hospital discharge and orotracheal intubation were used.

Results

Seventy-four patients treated with TCZ were matched with 148 matched controls. They were mainly males (81.5%), Caucasian (82.0%) and with a median age of 59 years. The majority (69.8%) showed critical stage COVID-19 disease. TCZ use was associated with a better overall survival (HR 0.499 [95% CI 0.262–0.952], p = 0.035) compared to controls but with a longer hospital stay (HR 1.658 [95% CI 1.088–2.524], p = 0.019) mainly due to biochemical, respiratory and infectious adverse events.

Discussion

TCZ use resulted potentially effective on COVID-19 in terms of overall survival. Caution is warranted given the potential occurrence of adverse events.

Financial support

Some of the tocilizumab doses used in the subjects included in this analysis were provided by the “Multicenter study on the efficacy and tolerability of tocilizumab in the treatment of patients with COVID-19 pneumonia” (EudraCT Number: 2020-001110-38) supported by the Italian National Agency for Drugs (AIFA). No specific funding support was planned for study design, data collection and analysis and manuscript writing of this paper.

Translating traditional herbal formulas into modern drugs: a network-based analysis of Xiaoyao decoction

Background

Traditional Chinese medicine (TCM) encompasses numerous herbal formulas which play critical therapeutic roles through "multi-components, multi-targets and multi-pathways" mechanisms. Exploring the interaction among these mechanisms can certainly help to depict the core therapeutic function of herbal formulas. Xiaoyao decoction (XYD) is one of the most well-known traditional Chinese medicine formulas which has been widely applied to treat various diseases. In this study, taking XYD as an example, we proposed a network pharmacology-based method to identify the main therapeutic targets of this herbal concoctions.

Methods

Chemical data of XYD were retrieved from the Traditional Chinese Medicine Systems Pharmacology Database (TCMSP), Traditional Chinese Medicines Integrated Database (TCMID) and Compound Reference Database (CRD) and screened oral bioavailability attributes from SwissADME using Veber's filter. Targets of sample chemicals were identified using the online tool similarity ensemble approach (SEA), and pathways were enriched using STRING database. On the basis of targets-pathways interactions from the enrichment, a "targets-pathways-targets" (TPT) network was constructed. In the TPT network, the importance of each target was calculated by the declining value of network efficiency, which represents the influential strength of a specific set-off target on the whole network. Network-based predictive results were statistically validated with existing experimental evidence.

Results

The TPT network was comprised of 279 nodes and 6549 edges. The declining value of network efficiency of the sample targets was significantly correlated with their involvement frequency in existing studies of XYD using Spearman's test (p < 0.001). The top 10% of candidate targets, such as AKT1, PIK3R1, NFKB1 and RELA, etc., were chosen as XYD's main therapeutic targets, which further show pharmacological functions synergistically through 11 main pathways. These pathways are responsible for endocrine, nutritional or metabolic diseases, neoplasms and diseases of the nervous system, etc.

Conclusions

The network pharmacology-based approach in the present study shows promising potential for identifying the main therapeutic targets from TCM formulas. This study provides valuable information for TCM researchers and clinicians for better understanding the main therapeutic targets and therapeutic roles of herbal decoctions in clinical settings.

Approach to Peribronchovascular Disease on CT

Diseases that are predominantly peribronchovascular in distribution on computed tomography by definition involve the bronchi, adjacent vasculature, and associated lymphatics involving the central or axial lung interstitium. An understanding of diseases that can present with focal peribronchovascular findings is useful for establishing diagnoses and guiding patient management. This review will cover clinical and imaging features that may assist in differentiating amongst the various causes of primarily peribronchovascular disease.