ACAT2 suppresses the ubiquitination of YAP1 to enhance the proliferation and metastasis ability of gastric cancer via the upregulation of SETD7.

The contributions of aberrantly expressed metabolic enzymes to gastric cancer (GC) initiation and progression have been widely appreciated in recent years. Acetyl-CoA acetyltransferase 2 (ACAT2) is one member of the acetyl- CoA thiolase family. Previous studies demonstrated that ACAT2 either promotes or suppresses tumor progression in different conditions. However, the function and mechanisms of ACAT2 in GC remain unknown. We found that the expression of this enzyme was significantly increased in GC tissues compared with normal counterparts, which prompted us to further investigate the roles of this protein in GC biology. In vitro functional studies showed that ACAT2 knockdown markedly halted the proliferation and the motility of GC cells; these functions favoring malignant phenotypes of GC cells were further validated in animal experiments. Mechanistically, ACAT2 depletion significantly reduced the transcription of SETD7, which is a histone methyltransferase and plays critical roles in GC cells. We found that the pro-tumoral functions of ACAT2 were largely dependent on SETD7. Moreover, SETD7 decreased the ubiquitination level of Yes-associated protein 1 (YAP1), thereby protecting YAP1 from proteasome degradation. Increased YAP1 protein expression remarkably activated the YAP1/TAZ-TEAD1 signaling pathway, which further boosted the malignant phenotypes in GC cells. In conclusion, these findings highlight the pro-tumoral functions and molecular underpinnings of ACAT2 in GC cells, and suggest that ACAT2 could be a promising target in GC treatment.

Progranulin inhibits fibrosis by interacting with and up-regulating DNAJC3 during mouse skin wound healing.

Scars place a heavy burden on both individuals and society. Our previous study found that reduction of progranulin (PGRN) promotes fibrogenesis in mouse skin wound healing. However, the underlying mechanisms have not been elucidated. Here, we report that PGRN overexpression decreases the expression of profibrotic genes alpha-smooth muscle actin (αSMA), serum response factor (SRF), and connective tissue growth factor (CTGF), thereby inhibiting skin fibrosis during wound repair. Bioinformatics analysis suggested that the heat shock protein (Hsp) 40 superfamily C3 (DNAJC3) is a potential downstream molecule of PGRN. Further experiments showed that PGRN interacts with and upregulates DNAJC3. Moreover, this antifibrotic effect was rescued by DNAJC3 knockdown. In summary, our study suggests that PGRN inhibits fibrosis by interacting with and upregulating DNAJC3 during wound healing in mouse skin. Our study provides a mechanistic explanation of the effect of PGRN on fibrogenesis in skin wound healing.

Initial clinical and experimental analyses of ALDOA in gastric cancer, as a novel prognostic biomarker and potential therapeutic target.

The effect of ALDOA, an important regulator of tumor metabolism and immune cell function, on gastric cancer (GC) immune infiltration has not been elucidated. Hence, we explored the feasibility of using ALDOA combined with immune molecular markers as novel prognostic or therapeutic targets for GC patients. Bioinformatic analyses were initially performed in multiple databases to assess the prognostic prediction values of ALDOA expression in GC. Subsequently, both ALDOA expression and the clinicopathological characteristics of a total of 114 GC patients who underwent curative gastrectomy were collected to demonstrate the potential association between ALDOA expression and the biological behaviors of GC. Next, the expression of ALDOA and its effect on prognosis were determined at the mRNA and protein levels, respectively, using tissue microarrays and cellular experiments. Subsequently, several molecular mechanisms were revealed based on elaborate analyses, indicating that ALDOA expression was potentially involved in the progression of GC and could be considered a promising biomarker for evaluating the prognosis of GC. High ALDOA expression was frequently found in GC cells and GC tissues at the mRNA and protein levels. Based on survival analysis, the expression of ALDOA indicated comparatively poor overall survival (OS) in GC and was identified as an independent prognostic predictor of GC. Correlation analysis showed that ALDOA expression had a positive association with lymph node metastasis in GC patients. Additionally, microRNA-1179 was found to play a key role in inhibiting the expression of ALDOA in the metabolic pathways of GC cells, which might disrupt the expression of various immune molecules and be detrimental to the prognosis of GC. ALDOA should be considered a promising molecular target for evaluating the prognosis of GC, owing to its potential role in immune regulation.

MiR-574-5p promotes cell proliferation by negatively regulating small C-terminal domain phosphatase 1 in esophageal squamous cell carcinoma.

Objectives: Esophageal cancer is one of the most common cancers with high incidence and mortality rates, especially in China. MicroRNA (miRNA) can be used as a prognostic marker for various human cancers. This study aims to detect suitable miRNA markers for esophageal squamous cell carcinoma (ESCC). Materials and Methods: Our previous gene expression data of ESCC cells and the data from GSE43732 and GSE112840 were analyzed. The expression of miR-574-5p in ESCC patients and controls was analyzed by real-time quantitative PCR. The effect of miR-574-5p on proliferation was detected by real-time cell analysis (RTCA) and EdU proliferation assay after cell transfections. The target gene small C-terminal domain phosphatase 1 (CTDSP1) of miR-574-5p was validated by luciferase reporter assay and western blotting. Results: In the current study, the bioinformatics analysis found miR-574-5p up-regulated in ESCC. The qPCR assay of 26 ESCC and 13 adjacent/ normal tissues confirmed these results. We further demonstrated that miR-574-5p overexpression promoted cell proliferation. Then the dual-luciferase reporter assay and the rescue experiment suggested that CTDSP1 was a direct target of miR-574-5p. Conclusion: MiR-574-5p played an oncological role in ESCC by interacting and negatively regulating CTDSP1. These results provided a deeper understanding of the effect of miR-574-5p on ESCC.

miR-351 promotes atherosclerosis in diabetes by inhibiting the ITGB3/PIK3R1/Akt pathway and induces endothelial cell injury and lipid accumulation.

BACKGROUND: The miR-351 gene is significantly upregulated in diabetic mice with atherosclerosis. However, the mechanism by which its presence is important for the overall disease has not been elucidated. Therefore, this study will investigate the mechanism of miR-351 in the process of diabetes mellitus with atherosclerosis through miR-351 gene knockout mice. METHODS: In this study, miR-351-/- C57BL/6 mice were first induced to form a type 2 diabetes mellitus model with atherosclerosis by STZ injection and a high-fat diet. Pathological tests (oil red O, HE, and Masson staining) combined with biochemical indices (TC, TG, LDL-C, HDL-C, TNF-α, hs-CRP, NO, SOD, MDA, CAT, and GSH-Px) were performed to evaluate the pathological degree of atherosclerosis in each group. Mouse aortic endothelial cells were treated with oxidized low-density lipoprotein (ox-LDL) and 30 mM glucose to establish a diabetic atherosclerosis cell model. Combined with cell oil red O staining and flow cytometry, the effects of silencing miR-351 on lipid accumulation and cell apoptosis in the diabetic atherosclerosis cell model were determined. Fluorescence in situ hybridization was used to detect the localization and transcription levels of miR-351 in cells. The target genes of miR-351 were predicted by bioinformatics and verified by dual-luciferase activity reporting. Western blotting was used to detect the expression levels of phosphorylated inosine 3-kinase regulatory subunit 1 (PIK3R1)/serine/threonine kinase 1 (Akt) and apoptosis-related proteins after transfection with integrin subunit ß3 (ITGB3) small interfering ribonucleic acid (siRNA). RESULTS: The expression of the miR-351 gene was significantly increased in the high-fat wild-type (HWT) group, and its expression was significantly decreased in the knockout mice. Silencing miR-351 effectively alleviated atherosclerosis in mice. The levels of miR-351 expression, apoptosis, lipid accumulation, and oxidative stress in ox-LDL + high glucose-induced endothelial cells were significantly increased. These phenomena were effectively inhibited in lentivirus-infected miR-351-silenced cell lines. Bioinformatics predicted that miR-351-5p could directly target the ITGB3 gene. Transfection of ITGB3 siRNA reversed the downregulation of apoptosis, decreased oil accumulation, and decreased oxidative stress levels induced by miR-351 silencing. In addition, it inhibited the activation of the PIK3R1/Akt pathway. CONCLUSION: Silencing miR-351 upregulates ITGB3 and activates the PIK3R1/Akt pathway, thereby exerting anti-apoptosis and protective effects on endothelial cells.

Establishment and verification of prognostic model for gastric cancer based on autophagy-related genes.

Autophagy played a significant role in the development of cancer. In this study, we explored the value of autophagy-associated genes in gastric cancer. RNA sequencing and clinical information containing 375 gastric cancer and 32 normal tissues were gathered from the TCGA portal. Then we stochastically allocated the autophagy-associated genes (AAGs) to training and testing groups. Next, we screened the discrepantly expressed AAGs and the prognostic AAGs by Cox regression analysis and Lasso regression analysis. Afterwards, we structured the model by using the prognostic AAGs and plotted Kaplan-Meier (KM) and receiver operating characteristic (ROC) curves to verify the performance of models in both groups. Besides, we utilized Gene Ontology (GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses to explore the molecular mechanisms of AAGs in gastric cancer. Finally, we demonstrated discrepant expression of AAGs within gastric cancer and non-tumor tissues at protein level with immunohistochemistry. 28 discrepantly expressed AAGs were screened from the TCGA database which contained 375 gastric cancer and 32 non-tumor samples. Cox and Lasso regression analyses were performed in training group and then we got 5 prognostic AAGs to establish the prognostic model. The patients who had high risk possessed worse overall survival (OS) both in training group (5-year OS, 47.6% vs 23.1%; P < 0.0001) and test group (5-year OS, 49.2% vs 0%, P=0.019). The proportion under ROC curves (AUC) were significant both in training group and test group (5-year AUC, 0.736 vs 0.809). Through this study, we constructed a model for gastric cancer patients which may provide individual treatment and superior prognosis.

Identification of a clinical compound losmapimod that blocks Lassa virus entry.

Lassa virus (LASV) causes Lassa hemorrhagic fever in humans and poses a significant threat to public health in West Africa. Current therapeutic treatments for Lassa fever are limited, making the development of novel countermeasures an urgent priority. In this study, we identified losmapimod, a p38 mitogen-activated protein kinase (MAPK) inhibitor, from 102 screened compounds as an inhibitor of LASV infection. Losmapimod exerted its inhibitory effect against LASV after p38 MAPK down-regulation, and, interestingly, had no effect on other arenaviruses capable of causing viral hemorrhagic fever. Mechanistic studies showed that losmapimod inhibited LASV entry by affecting the stable signal peptide (SSP)-GP2 subunit interface of the LASV glycoprotein, thereby blocking pH-dependent viral fusion. As an aryl heteroaryl bis-carboxyamide derivative, losmapimod represents a novel chemical scaffold with anti-LASV activity, and it provides a new lead structure for the future development of LASV fusion inhibitors.

Microbial Natural Product Alternariol 5-O-Methyl Ether Inhibits HIV-1 Integration by Blocking Nuclear Import of the Pre-Integration Complex.

While Highly Active Antiretroviral Therapy (HAART) has significantly decreased the mortality of human immunodeficiency virus (HIV)-infected patients, emerging drug resistance to approved HIV-1 integrase inhibitors highlights the need to develop new antivirals with novel mechanisms of action. In this study, we screened a library of microbial natural compounds from endophytic fungus Colletotrichum sp. and identified alternariol 5-O-methyl ether (AME) as a compound that inhibits HIV-1 pre-integration steps. Time-of addition analysis, quantitative real-time PCR, confocal microscopy, and WT viral replication assay were used to elucidate the mechanism. As opposed to the approved integrase inhibitor Raltegravir, AME reduced both the integrated viral DNA and the 2-long terminal repeat (2-LTR) circular DNA, which suggests that AME impairs the nuclear import of viral DNA. Further confocal microscopy studies showed that AME specifically blocks the nuclear import of HIV-1 integrase and pre-integration complex without any adverse effects on the importin α/ß and importin ß-mediated nuclear import pathway in general. Importantly, AME inhibited Raltegravir-resistant HIV-1 strains and exhibited a broad anti-HIV-1 activity in diverse cell lines. These data collectively demonstrate the potential of AME for further development into a new HIV inhibitor, and suggest the utility of viral DNA nuclear import as a target for anti-HIV drug discovery.

Neurofibromin Regulates Seizure Attacks in the Rat Pilocarpine-Induced Model of Epilepsy.

Studies have shown that neurofibromin (NF1) restricts GABA release at inhibitory synapses and regulates dendritic spine formation, which may play an important role in temporal lobe epilepsy (TLE). NF1 expression was detected by double-label immunofluorescence, immunohistochemistry, and western blot analysis in the brains of pilocarpine-induced epilepsy model rats at 6 h, 24 h, 72 h, 7 days, 14 days, 30 days, and 60 days after kindling. NF1 was localized primarily in the nucleus and cytoplasm of neurons. NF1 protein levels significantly increased in the chronic phase (from 7 days until 60 days) in this epileptic rat model. After NF1 expression was knocked down by specific siRNA, the effects of kindling with pilocarpine were evaluated on the 7th day after kindling. The onset latencies of pilocarpine-induced seizures were elevated, and the seizure frequency and duration were reduced in these rats. Our study demonstrates that NF1 promoted seizure attacks in rats with pilocarpine-induced epilepsy.

Generalized tonic-clonic seizures in adult patients following intravenous administration of desmopressin.

Desmopressin is a synthetic replacement for vasopressin, which is used to reduce perioperative blood loss. However, seizure attacks were observed in patients after administration of desmopressin. Here, we reported two cases of adult Chinese patients experienced generalized tonic-clonic seizures associated with severe hyponatremia caused by intravenously administered desmopressin after surgery. The patients' neurological conditions returned to baseline quickly and completely following discontinuation of desmopressin, control of the seizures, and fluid intake restriction. These cases illustrate the importance of periodic monitoring of electrolyte concentrations and fluid intake during use of desmopressin.