Choigreene7688

Salmonella typhimurium (S. typhimurium) infection of macrophage induces NLRC4 inflammasome-mediated production of the pro-inflammatory cytokines IL-1β. Post-translational modifications on NLRC4 are critical for its activation. Sirtuin3 (SIRT3) is the most thoroughly studied mitochondrial nicotinamide adenine dinucleotide (NAD+) -dependent deacetylase. We wondered whether SIRT3 mediated-deacetylation could take part in NLRC4 inflammasome activation. Methods We initially tested IL-1β production and pyroptosis after cytosolic transfection of flagellin or S. typhimurium infection in wild type and SIRT3-deficient primary peritoneal macrophages via immunoblotting and ELISA assay. These results were confirmed in SIRT3-deficient immortalized bone marrow derived macrophages (iBMDMs) which were generated by CRISPR-Cas9 technology. In addition, in vivo experiments were conducted to confirm the role of SIRT3 in S. typhimurium-induced cytokines production. Then NLRC4 assembly was analyzed by immune-fluorescence assay and tylation of NLRC4 is pivotal for NLRC4 activation and the acetylation switch of NLRC4 may aid the clearance of S. typhimurium infection.Death receptor 4 (DR4), a cell surface receptor, mediates apoptosis or induces inflammatory cytokine secretion upon binding to its ligand depending on cell contexts. Its prognostic impact in lung cancer and connection between EGFR-targeted therapy and DR4 modulation has not been reported and thus was the focus of this study. Methods Intracellular protein alterations were measured by Western blotting. Cell surface protein was detected with antibody staining and flow cytometry. mRNA expression was monitored with qRT-PCR. Gene transactivation was analyzed with promoter reporter assay. Drug dynamic effects in vivo were evaluated using xenografts. Gene modulations were achieved with gene overexpression and knockdown. Proteins in human archived tissues were stained with immunohistochemistry. Results EGFR inhibitors (e.g., osimertinib) decreased DR4 levels only in EGFR mutant NSCLC cells and tumors, being tightly associated with induction of apoptosis. This modulation was lost once cells became resistant to these inhibitors. Increased levels of DR4 were detected in cell lines with acquired osimertinib resistance and in NSCLC tissues relapsed from EGFR-targeted therapy. DR4 knockdown induced apoptosis and augmented apoptosis when combined with osimertinib in both sensitive and resistant cell lines, whereas enforced DR4 expression significantly attenuated osimertinib-induced apoptosis. Mechanistically, osimertinib induced MARCH8-mediated DR4 proteasomal degradation and suppressed MEK/ERK/AP-1-dependent DR4 transcription, resulting in DR4 downregulation. Moreover, we found that DR4 positive expression in human lung adenocarcinoma was significantly associated with poor patient survival. Conclusions Collectively, we suggest that DR4 downregulation is coupled to therapeutic efficacy of EGFR-targeted therapy and predicts improved prognosis, revealing a previously undiscovered connection between EGFR-targeted therapy and DR4 modulation.[This corrects the article DOI 10.7150/thno.23177.].[This corrects the article DOI 10.7150/thno.20846.].Background Pacemaker implantation is currently used in patients with symptomatic bradycardia. Since a pacemaker is a lifetime therapeutic device, its energy consumption contributes to battery exhaustion, along with its voltage stimulation resulting in local fibrosis and greater resistance, which are all detrimental to patients. The possible resolution for those clinical issues is an injection of a conductive hydrogel, poly-3-amino-4-methoxybenzoic acid-gelatin (PAMB-G), to reduce the myocardial threshold voltage for pacemaker stimulation. Methods PAMB-G is synthesized by covalently linking PAMB to gelatin, and its conductivity is measured using two-point resistivity. Rat hearts are injected with gelatin or PAMB-G, and pacing threshold is evaluated using electrocardiogram and cardiac optical mapping. Results PAMB-G conductivity is 13 times greater than in gelatin. The ex vivo model shows that PAMB-G significantly enhances cardiac tissue stimulation. Injection of PAMB-G into the stimulating electrode location at the myocardium has a 4 times greater reduction of pacing threshold voltage, compared with electrode-only or gelatin-injected tissues. Multi-electrode array mapping reveals that the cardiac conduction velocity of PAMB-G group is significantly faster than the non- or gelatin-injection groups. https://www.selleckchem.com/products/bay-218.html PAMB-G also reduces pacing threshold voltage in an adenosine-induced atrial-ventricular block rat model. Conclusion PAMB-G hydrogel reduces cardiac pacing threshold voltage, which is able to enhance pacemaker efficacy.The tumor microenvironment contributes to tumor progression and metastasis. Cancer-associated fibroblasts (CAFs) form a major cellular component of the tumor microenvironment. In this study, we further explored the mechanisms underlying the tumor-promoting roles of CAFs. Methods Patient-derived CAFs and normal fibroblasts (NFs) were isolated from breast carcinomas and adjacent normal breast tissue. Exosomes were isolated by ultracentrifugation and CAF-derived exosomal microRNAs were screened using next-generation sequencing technology. MiR-500a-5p expression was assessed by quantitative real-time polymerase chain reaction (qRT-PCR) and in situ hybridization; Tumor cell proliferation was determined by MTT assays and three-dimensioned (3D) cultures, and tumor metastasis was determined by Transwell assays in vitro. In vivo assays were performed in a nude mouse subcutaneous xenograft model. Results We confirmed that CAF-derived exosomes significantly promoted the proliferation and metastasis of breast cancer cells. MiR-500a-5p was highly expressed in MDA-MB-231 and MCF7 cells treated with CAF-derived exosomes. The upregulation of miR-500a-5p was also confirmed in CAFs and CAF-derived exosomes. MiR-500a-5p was transferred from CAFs to the cancer cells, and subsequently promoted proliferation and metastasis by binding to ubiquitin-specific peptidase 28 (USP28). Conclusions The present study demonstrates that CAFs promote breast cancer progression and metastasis via exosomal miR-500a-5p and indicate that inhibiting CAF-derived miR-500a-5p is an alternative modality for the treatment of breast cancer.