Inflammasomes are intracellular sensors that couple detection of pathogens and cellular stress to activation of Caspase-1, and consequent IL-1β and IL-18 maturation and pyroptotic cell death. Here, we show that the absent in melanoma 2 (AIM2) and nucleotidebinding oligomerization domain-like receptor pyrin domain-containing protein 3 (NLRP3) inflammasomes trigger Caspase-1-dependent mitochondrial damage. Caspase-1 activates multiple pathways to precipitate mitochondrial disassembly, resulting in mitochondrial reactive oxygen species (ROS) production, dissipation of mitochondrial membrane potential, mitochondrial permeabilization, and fragmentation of the mitochondrial network. Moreover, Caspase-1 inhibits mitophagy to amplify mitochondrial damage, mediated in part by cleavage of the key mitophagy regulator Parkin. In the absence of Parkin activity, increased mitochondrial damage augments pyroptosis, as indicated by enhanced plasma membrane permeabilization and release of danger-associated molecular patterns (DAMPs). Therefore, like other initiator caspases, Caspase-1 activation by inflammasomes results in mitochondrial damage.inflammasomes | mitochondrial damage | pyroptosis | mitophagy

To examine transmission dynamics of Mtb isolated from TB patients in Ho Chi Minh City, Vietnam we sequenced whole genomes of 1,635 isolates and compared these with 3,144 isolates from elsewhere. The data reveal an underlying burden of disease caused by endemic Mtb Lineage 1 associated with activation of long-term latent infection, and a three-fold higher burden associated with more recently introduced Beijing lineage and Lineage 4 Mtb strains. We find that Beijing lineage Mtb is frequently transferred between Vietnam and other countries, and detect higher levels of transmission of Beijing lineage strains within this host population than endemic Lineage 1 Mtb. Screening for parallel evolution of Beijing lineage-associated SNPs in other Mtb lineages as a signal of positive selection, we identify a mutation in the ESX-5 type VII secreted protein EsxW, which could potentially contribute to the enhanced transmission of Beijing lineage Mtb in Vietnamese and other host populations.

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This study was conducted to clarify the role of cytoglobin (Cygb), a globin expressed in hepatic stellate cells (HSCs), in the development of liver fibrosis and cancer in nonalcoholic steatohepatitis (NASH). Cygb expression was assessed in patients with NASH and hepatocellular carcinoma. Mouse NASH model was generated in Cygb-deficient (Cygb(-/-)) or wild-type (WT) mice by giving a choline-deficient amino acid-defined diet and, in some of them, macrophage deletion and N-acetyl cysteine treatment were used. Primary-cultured mouse HSCs isolated from WT (HSCs(Cygb-wild)) or Cygb(-/-) (HSCs(Cygb-null)) mice were characterized. As results, the expression of CYGB was reduced in patients with NASH and hepatocellular carcinoma. Choline-deficient amino acid treatment for 8 weeks induced prominent inflammation and fibrosis in Cygb(-/-) mice, which was inhibited by macrophage deletion. Surprisingly, at 32 weeks, despite no tumor formation in the WT mice, all Cygb(-/-) mice developed liver cancer, which was ameliorated by N-acetyl cysteine treatment. Altered expression of 31 genes involved in the metabolism of reactive oxygen species was notable in Cygb(-/-) mice. Both HSCs(Cygb-null) and Cygb siRNA-transfected-HSCs(Cygb-wild) exhibited the preactivation condition. Our findings provide important insights into the role that Cygb, expressed in HSCs during liver fibrosis, plays in cancer development with NASH.

Liver cancer ranks sixth in cancer incidence, and is the third leading cause of cancer-related deaths worldwide. Hepatocellular carcinoma (HCC) is the most common type of liver cancer, which arises from hepatocytes and accounts for approximately 70%-85% of cases. Hepatitis B virus (HBV) frequently causes liver inflammation, hepatic damage and subsequent cirrhosis. Integrated viral DNA is found in 85%-90% of HBV-related HCCs. Its presence in tumors from non-cirrhotic livers of children or young adults further supports the role of viral DNA integration in hepatocarcinogenesis. Integration of subgenomic HBV DNA fragments into different locations within the host DNA is a significant feature of chronic HBV infection. Integration has two potential consequences: (1) the host genome becomes altered ("cis" effect); and (2) the HBV genome becomes altered ("trans" effect). The cis effect includes insertional mutagenesis, which can potentially disrupt host gene function or alter host gene regulation. Tumor progression is frequently associated with rearrangement and partial gain or loss of both viral and host sequences. However, the role of integrated HBV DNA in hepatocarcinogenesis remains controversial. Modern technology has provided a new paradigm to further our understanding of disease mechanisms. This review summarizes the role of HBV DNA integration in human carcinogenesis.

In hepatocellular carcinoma (HCC), the clinical significance of soluble immune checkpoint protein levels as predictors of patient outcomes or therapeutic responses has yet to be defined. This study profiled the baseline levels of sixteen soluble checkpoint proteins and their changes following sorafenib treatment for HCC. Plasma samples were obtained from 53 patients with advanced HCC at baseline, week 1, 2 and 4 of sorafenib treatment and tested the concentrations of 16 soluble checkpoint proteins using multiplexed fluorescent bead-based immunoassays. Multivariate analysis showed high sBTLA levels at baseline were an independent predictor of poor overall survival (p = 0.038). BTLA was highly expressed in T cells and macrophages in peritumoral areas. At week 2, sCD27 levels were decreased compared to baseline. By contrast, the concentrations of most inhibitory proteins, including sBTLA, sLAG-3, sCTLA-4, sPD-1, sCD80, sCD86 and sPD-L1, had significantly increased. The fold-changes of soluble checkpoint receptors and their ligands, including sCTLA-4 with sCD80/sCD86, sPD-1 with sPD-L1; and the foldchanges of sCTLA-4 with sBTLA or sPD-1 were positively correlated. sBTLA may be a good biomarker for predicting overall survival in HCC patients. Sorafenib treatment in patients with advanced HCC revealed dynamic changes of soluble checkpoint protein levels.

In this paper, molecular dynamics simulations of a simple Lennard-Jones fluid confined in narrow slit pores and undergoing shear have been performed. The aim is to investigate the effects of density inhomogeneities at the fluid-solid interfaces on the shear viscosity profiles. It has been found that the local viscosity was varying strongly with the distance from the solid walls for both dilute and dense fluid states with oscillations correlated to the density ones. To describe the computed viscosity profiles, we propose a scheme that uses the local average density model, combined with an adequate weight function, for the configurational viscosity and a semiempirical model for the translational viscosity. It is shown that the proposed approach is able to provide viscosity profiles in good agreement with those coming from simulations for different pore widths and for different fluid states (dilute to dense).

Using molecular dynamics simulations on inhomogeneous fluids, we have studied the effects of strong density inhomogeneities of varying wavelengths on the shear viscosity computed locally. For dense fluids, the local average density model combined with an adequate weight function yields a good description of the viscosity profiles obtained by simulations. However, for low density inhomogeneous fluids, the local average density model is unable to describe correctly the viscosity profiles obtained by simulations. It is shown that this weakness can be overcome by taking into account the density inhomogeneity in the local translational contribution to the viscosity using a density gradient like approach.