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The X90 pipeline steel pipe is expected to become the standard steel in future pipeline construction due to its high transmission efficiency and lower cost. However, little study has been conducted on corrosion on-line monitoring of X90 steel. To investigate the pitting development of X90 steel, a combined electrochemical device and acoustic emission (AE) system was set up in this work. The results reveal that the pitting process can be divided into three stages: activation response and passive film rupture, and corrosion pit propagation, and pitting reaction. In addition, the corrosion rate of metal is quite high during the activation reaction and passivation film rupture stage, and the characteristic parameters of the AE signal are very large. In the frequency domain, the frequency range is mostly centered between 100 and 200 kHz, with a peak frequency of about 150 kHz. The corrosion pit propagation stage is the transition stage from metal oxidation to metal pitting reaction. The activity of the signal is low, and the characteristic signal is diminished, and the frequency domain characteristics are comparable to the preceding stage. The signal activity rises, the total signal intensity increases, and several signals exceeding 55 dB arise during the pitting response stage.

Background & Aims: Exploiting key regulators responsible for hepatocarcinogenesis is of great importance for the prevention and treatment of hepatocellular carcinoma (HCC). However, the key players contributing to hepatocarcinogenesis remain poorly understood. We explored the molecular mechanisms underlying the carcinogenesis and progression of HCC for the development of potential new therapeutic targets. Methods: The Cancer Genome Atlas-Liver Hepatocellular Carcinoma (TCGA-LIHC) and Genotype-Tissue Expression (GTEx) databases were used to identify genes with enhanced expression in the liver associated with HCC progression. A murine liver-specific Ftcd knockout (Ftcd-LKO) model was generated to investigate the role of formimidoyltransferase cyclodeaminase (FTCD) in HCC. Multi-omics analysis of transcriptomics, metabolomics, and proteomics data were applied to further analyse the molecular effects of FTCD expression on hepatocarcinogenesis. Functional and biochemical studies were performed to determine the significance of loss of FTCD expression and the therapeutic potential of Akt inhibitors in FTCD-deficient cancer cells. Results: FTCD is highly expressed in the liver but significantly downregulated in HCC. Patients with HCC and low levels of FTCD exhibited worse prognosis, and patients with liver cirrhosis and low FTCD levels exhibited a notable higher probability of developing HCC. Hepatocyte-specific knockout of FTCD promoted both chronic diethylnitrosamine-induced and spontaneous hepatocarcinogenesis in mice. Multi-omics analysis showed that loss of FTCD affected fatty acid and cholesterol metabolism in hepatocarcinogenesis. Mechanistically, loss of FTCD upregulated peroxisome proliferator-activated receptor (PPAR)γ and sterol regulatory element–binding protein 2 (SREBP2) by regulating the PTEN/Akt/mTOR signalling axis, leading to lipid accumulation and hepatocarcinogenesis. Conclusions: Taken together, we identified a FTCD-regulated lipid metabolic mechanism involving PPARγ and SREBP2 signaling in hepatocarcinogenesis and provide a rationale for therapeutically targeting of HCC driven by downregulation of FTCD. Impact and implications: Exploiting key molecules responsible for hepatocarcinogenesis is significant for the prevention and treatment of HCC. Herein, we identified formimidoyltransferase cyclodeaminase (FTCD) as the top enhanced gene, which could serve as a predictive and prognostic marker for patients with HCC. We generated and characterised the first Ftcd liver-specific knockout murine model. We found loss of FTCD expression upregulated peroxisome proliferator-activated receptor (PPAR)γ and sterol regulatory element–binding protein 2 (SREBP2) by regulating the PTEN/Akt/mTOR signalling axis, leading to lipid accumulation and hepatocarcinogenesis, and provided a rationale for therapeutic targeting of HCC driven by downregulation of FTCD.

With the development of synthesis technology, modified messenger RNA (mRNA) has emerged as a novel category of therapeutic agents for a broad of diseases. However, effective intracellular delivery of mRNA remains challenging, especially for its sensitivity to enzymatic degradation. Here, we propose a polyphenol-assisted handy delivery strategy for efficient in vivo delivery of IL-10 mRNA. IL-10 mRNA binds to polyphenol ellagic acid through supramolecular binding to yield a negatively charged core, followed by complexing with linear polyetherimide and coating with bilirubin-modified hyaluronic acid to obtain a layer-by-layer nanostructure. The nanostructure specifically up-regulated the level of IL-10, effectively inhibited the expression of inflammatory factors, promoted mucosal repair, protected colonic epithelial cells against apoptosis, and exerted potent therapeutic efficacy in dextran sulfate sodium salt-induced acute and chronic murine models of colitis. The designed delivery system without systemic toxicity has the potential to facilitate the development of a promising platform for mRNA delivery in ulcerative colitis treatment.

Summary: Membraneless condensates, such as stress granules (SGs) and processing bodies (P-bodies), have attracted wide attention due to their unique feature of rapid response to stress without first requiring nuclear feedback. In this study, we identify diaphanous-related formin 3 (DIAPH3), an actin nucleator, as a scaffold protein to initiate liquid-liquid phase separation (LLPS) and form abundant cytosolic phase-separated DIAPH3 granules (D-granules) in mammalian cells such as HeLa, HEK293, and fibroblasts under various stress conditions. Neither mRNAs nor known stress-associated condensate markers, such as G3BP1, G3BP2, and TIA1 for SGs and DCP1A for P-bodies, are detected in D-granules. Using overexpression and knockout of DIAPH3, pharmacological interventions, and optogenetics, we further demonstrate that stress-induced D-granules spatially sequester DIAPH3 within the condensation to inhibit the assembly of actin filaments in filopodia. This study reveals that D-granules formed by LLPS act as a regulatory hub for actin cytoskeletal remodeling in response to stress.

Summary: Background: Identification of tumor dependencies is important for developing therapeutic strategies for liver cancer. Methods: A genome-wide CRISPR screen was performed for finding critical vulnerabilities in liver cancer cells. Compounds screen, RNA sequencing, and human phospho-receptor tyrosine kinase arrays were applied to explore mechanisms and search for synergistic drugs. Findings: We identified mitochondrial translation-related genes associated with proliferation for liver cancer cells. Tigecycline induced deficiency of respiratory chain by disturbing mitochondrial translation process and showed therapeutic potential in liver cancer. For liver cancer cells extremely insensitive to tigecycline, a compounds screen was applied to identify MEK inhibitors as synergistic drugs to tigecycline-insensitive liver cancer cells. Mechanistically, sustained activation of EGFR-ERK1/2-MYC cascade conferred the insensitivity to tigecycline, which was mediated by enhanced secretion of EREG and AREG. Moreover, glycolytic enzymes, such as HK2 and PKM2 were upregulated to stimulate glycolysisin a MYC-dependent manner. Tigecycline induced respiratory chain deficiency in combination with cutting off EGFR-ERK1/2-MYC cascade by MEK inhibitors or EGFR inhibitors, resulting in decrease of both oxidative phosphorylation and glycolysis in liver cancer cells. Interpretation: Our study proved that blocking EGFR-ERK1/2-MYC cascade combined with tigecycline could be a potential therapeutic strategy for liver cancer. Funding: This work was funded by grants from the National Natural Science Foundation of China (82073039, 82222047, 81920108025), Program of Shanghai Academic/Technology Research Leader (22XD1423100), Shanghai Municipal Science and Technology Project (20JC1411100), 111 Project (B21024), Innovative Research Team of High-level Local Universities in Shanghai (SHSMU-ZDCX20212700, SHSMU-ZDCX20210802) and Shanghai Jiao Tong University School of Medicine (YG2019GD01).