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Breast cancer is known as the most prevalent cancer in women worldwide, and has an undeniable negative impact on public health, both physically, and mentally. This study aims to investigate the effects of toll‐like receptor 4 (TLR4) gene silencing on proliferation and apoptosis of human breast cancer cells to explore for a new theoretical basis for its treatment. TLR4 small interference RNA (siRNA) fragment recombinant plasmids were constructed, including TLR4 siRNA‐1, TLR4 siRNA‐2, and TLR4 siRNA‐3. Human breast cancer MCF‐7 and MDA‐MB‐231 cells were assigned into blank, negative control (NC), TLR4 siRNA‐1, TLR4 siRNA‐2, and TLR4 siRNA‐3 groups. MCF‐7 and MDA‐MB‐231 cell growth was detected by MTT assay. Apoptosis and cell cycle were determined by flow cytometry. Reverse transcription quantitative polymerase chain reaction (RT‐qPCR) and Western blot analysis were conducted to determine the expression of TLR4, CDK4, cyclin D1, Livin, Bcl‐2, p53, c‐FLIP, and caspase‐3. In comparison with the NC and blank groups, the TLR4 siRNA‐1, TLR4 siRNA‐2, and TLR4 siRNA‐3 groups showed decreased the expression of TLR4, inhibited proliferation of MCF‐7 and MDA‐MB‐231 cells and promoted MCF‐7 and MDA‐MB‐231 cell apoptosis, and the cells were blocked in G1 phase. In comparison with the NC and blank groups, in the TLR4 siRNA‐1, TLR4 siRNA‐2, and TLR4 siRNA‐3 groups, siRNA‐TLR4 significantly increased expression of p53 and caspase‐3 in MCF‐7 and MDA‐MB‐231 cells, while it decreased the expressions of CDK4, cyclinD1, Livin, Bal‐2, and c‐FLIP. The study demonstrates that TLR4 gene silencing inhibits proliferation and induces apoptosis of MCF‐7 and MDA‐MB‐231 cells. TLR4 gene silencing inhibits proliferation and induces apoptosis of MCF‐7 and MDA‐MB‐231 cells. [ABSTRACT FROM AUTHOR]

Sepsis, as a systemic inflammatory response syndrome (SIRS) subtype, is generally characterized by infection. Emerging evidence has highlighted dysregulated microRNAs (miRNAs) are involved in the progression of sepsis. The aim of the study was to investigate the effects of miR-335-5p on inflammatory responses in a septic mouse model. The hypothesis was subsequently asserted that the FASN gene and AMPK/ULK1 signaling pathway may participate in the regulation of miR-335-5p. A septic mouse model was established in order to validate the effect of miR-335-5p on the inflammatory response by means of suppressing the endogenous expression of FASN by siRNA against FASN in endothelial cells. A target prediction program and luciferase activity was employed to ascertain as to whether miR--335-5p targets FASN. The levels of inflammatory factors including IL-6 and IL-1β were determined by means of ELISA assay. RT-qPCR and western blot analysis were used to determine the AMPK/ULK1 signaling pathway-, apoptosis- and autophagy-related genes. Flow cytometry was employed in order to evaluate sepsis-induced cell apoptosis in response to miR-335-5p and FASN alternations. FASN was identified as a target gene of miR--335-5p. Gain- and loss-of-function studies revealed that miR-335-5p acted to enhance autophagy, reduce cell apoptosis, promote cell cycle entry in endothelial cells, and reduce inflammatory response through the modulation of pro- and anti-apoptotic factors in endothelial cells. The effect of miR-335-5p on endothelial cells was increased when FASN was suppressed by siRNA as well as when the AMPK/ULK1 signaling pathway was activated, suggesting that miR-335-5p influences sepsis by targeting and inhibiting FASN, and activating the AMPK/ULK1 signaling pathway. Our study provides evidence indicating that overexpressed miR-335-5p enhances autophagy by targeting FASN through activation of the AMPK/ULK1 signaling pathway working to alleviate the inflammatory response in septic mouse models, emphasizing the value of the functional upregulation of miR-335-5p as therapeutic strategy for sepsis. [ABSTRACT FROM AUTHOR]

Background: The transforming growth factor β1 (TGF-β1)-induced epithelial-mesenchymal transition (EMT) has been proven associated with the pathogenesis of asthmatic airway remodeling, in which the Wnt/β-catenin pathway plays an important role, notably with regard to TGF-β1. Recent studies have shown that 1α, 25-dihydroxyvitamin D3(1α, 25(OH)2D3) inhibits TGF-β1-induced EMT, although the underlying mechanism have not yet been fully elucidated., Methods: Alveolar epithelial cells were exposed to 1α, 25(OH)2D3, ICG-001, or a combination of both, followed by stimulation with TGF-β1. The protein expression of E-cadherin, α-smooth muscle actin, fibronectin, and β-catenin was analyzed by western blotting and immunofluorescence analysis. The mRNA transcript of Snail was analyzed using RT-qPCR, and matrix metalloproteinase 9 (MMP-9) activity was analyzed by gelatin zymogram. The activity of the Wnt/β-catenin signaling pathway was analyzed using the Top/Fop flash reporters., Results: Both 1α, 25(OH)2D3 and ICG-001 blocked TGF-β1-induced EMT in alveolar epithelial cells. In addition, the Top/Fop Flash reporters showed that 1α, 25(OH)2D3 suppressed the activity of the Wnt/β-catenin pathway and reduced the expression of target genes, including MMP-9 and Snail, in synergy with ICG-001., Conclusion: 1α, 25(OH)2D3 synergizes with ICG-001 and inhibits TGF-β1-induced EMT in alveolar epithelial cells by negatively regulating the Wnt/β-catenin signaling pathway.

BACKGROUND Studies have shown that intermittent hypoxia mimics obstructive sleep apnea in causing pulmonary inflammation, but the mechanism is not yet clear.TLR-4 is a recognized proinflammatory factor, so the purpose of this study was to assess the function of TLR-4 in pulmonary inflammation induced by chronic intermittent hypoxia simulating obstructive sleep apnea. MATERIAL AND METHODS Healthy male Wistar rats were divided into 3 groups (8 in each group): the normoxia control group (CG), the intermittent hypoxia group (IH), and the TLR4 antagonist TAK242 treatment group (3 mg/kg, daily), with exposure durations of 12 weeks and 16 weeks (HI). The morphological changes of lung tissue were determined with hematoxylin-eosin (HE) staining. The expressions of the TLR-4 pathway in lung tissue were tested by Western blotting and RT-PCR. The levels of IL-6 and TNF-a in serum and lung tissue were detected by enzyme-linked immunosorbent assay (ELISA). The levels of SOD and MDA in lung tissue were detected by use of SOD and MDA kits, respectively. RESULTS After TAK242 treatment, damage to lung tissue was increased, and the expressions of TLR-4, MYD88, P65, IL-6, TNF-α, MDA, and SOD were decreased. Intermittent hypoxic exposure caused alveolar expansion, thickening of alveolar septum, and fusion of adjacent alveoli into larger cysts under intermittent hypoxia in a time-dependent manner. Compared with the CG and HI groups, the mean lining interval (MLI) become more thickened and the alveolar destruction index (DI) increased significantly in the IH group. CONCLUSIONS Chronic intermittent hypoxia causes pulmonary inflammatory response and the inflammatory pathway involved in TLR4 receptor may be one of the mechanisms that trigger lung inflammation.

Breast cancer is known as the most prevalent cancer in women worldwide, and has an undeniable negative impact on public health, both physically, and mentally. This study aims to investigate the effects of toll-like receptor 4 (TLR4) gene silencing on proliferation and apoptosis of human breast cancer cells to explore for a new theoretical basis for its treatment. TLR4 small interference RNA (siRNA) fragment recombinant plasmids were constructed, including TLR4 siRNA-1, TLR4 siRNA-2, and TLR4 siRNA-3. Human breast cancer MCF-7 and MDA-MB-231 cells were assigned into blank, negative control (NC), TLR4 siRNA-1, TLR4 siRNA-2, and TLR4 siRNA-3 groups. MCF-7 and MDA-MB-231 cell growth was detected by MTT assay. Apoptosis and cell cycle were determined by flow cytometry. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blot analysis were conducted to determine the expression of TLR4, CDK4, cyclin D1, Livin, Bcl-2, p53, c-FLIP, and caspase-3. In comparison with the NC and blank groups, the TLR4 siRNA-1, TLR4 siRNA-2, and TLR4 siRNA-3 groups showed decreased the expression of TLR4, inhibited proliferation of MCF-7 and MDA-MB-231 cells and promoted MCF-7 and MDA-MB-231 cell apoptosis, and the cells were blocked in G1 phase. In comparison with the NC and blank groups, in the TLR4 siRNA-1, TLR4 siRNA-2, and TLR4 siRNA-3 groups, siRNA-TLR4 significantly increased expression of p53 and caspase-3 in MCF-7 and MDA-MB-231 cells, while it decreased the expressions of CDK4, cyclinD1, Livin, Bal-2, and c-FLIP. The study demonstrates that TLR4 gene silencing inhibits proliferation and induces apoptosis of MCF-7 and MDA-MB-231 cells., (© 2018 Wiley Periodicals, Inc.)