Search

Macrophages can undergo M1-like proinflammatory polarization with low oxidative phosphorylation (OXPHOS) and high glycolytic activities or M2-like anti-inflammatory polarization with the opposite metabolic activities. Here we show that M1-like macrophages induced by hepatitis B virus (HBV) display high OXPHOS and low glycolytic activities. This atypical metabolism induced by HBV attenuates the antiviral response of M1-like macrophages and is mediated by HBV e antigen (HBeAg), which induces death receptor 5 (DR5) via toll-like receptor 4 (TLR4) to induce death-associated protein 3 (DAP3). DAP3 then induces the expression of mitochondrial genes to promote OXPHOS. HBeAg also enhances the expression of glutaminases and increases the level of glutamate, which is converted to α-ketoglutarate, an important metabolic intermediate of the tricarboxylic acid cycle, to promote OXPHOS. The induction of DR5 by HBeAg leads to apoptosis of M1-like and M2-like macrophages, although HBeAg also induces pyroptosis of the former. These findings reveal novel activities of HBeAg, which can reprogram mitochondrial metabolism and trigger different programmed cell death responses of macrophages depending on their phenotypes to promote HBV persistence.

WNK lysine deficient protein kinase 4 (WNK4) has been shown to be significantly associated with cancer progression. Nevertheless, its involvement in gastric cancer (GC) is unclear. the objective of this work was to investigate the WNK4's regulatory mechanism in GC. Quantitative RT-PCR and immunoblots revealed that WNK4 expression was downregulated in GC and that low expression of WNK4 was strongly linked to poor prognosis. Functional assays including cell counting kit-8 assay and colony formation assay demonstrated that overexpression of WNK4 led to limited tumor proliferation both in vitro and in vivo, while the WNK4 reduction yielded to the opposite results. Gene Set Enrichment Analysis (GSEA) indicated a potential association between WNK4 and the signal transducer and activator of transcription (STAT3). WNK4 suppressed the phosphorylation of signal transducer and activator of transcription 3 (p-STAT3) in GC cells. the inhibition of the STAT3 pathway with Stattic reversed growth and proliferation induced by WNK4 knockdown in GC cells. these findings provide new insights for identifying key therapeutic targets for GC in the future. [ABSTRACT FROM AUTHOR]