Identification of novel biomarkers in breast cancer via integrated bioinformatics analysis and experimental validation.

Breast cancer (BC), an extremely aggressive malignant tumor, causes a large number of deaths worldwide. In this study, we pooled profile datasets from three cohorts to illuminate the underlying key genes and pathways of BC. Expression profiles GSE42568, GSE45827, and GSE124646, including 244 BC tissues and 28 normal breast tissues, were integrated and analyzed. Differentially expressed genes (DEGs) were screened out based on these three datasets. Functional analysis including Gene Ontology (GO) and Kyoto Encyclopedia of Gene and Genome (KEGG) pathway were performed using The Database for Annotation, Visualization and Integrated Discovery (DAVID). Moreover, Cytoscape with Search Tool for the Retrieval of Interacting Genes (STRING) and Molecular Complex Detection (MCODE) plugin were utilized to visualize protein protein interaction (PPI) of these DEGs. The module with the highest connectivity of gene interactions was selected for further analysis. All of these hub genes had a significantly worse prognosis in BC by survival analysis. Additionally, four genes (CDK1, CDC20, AURKA, and MCM4) dramatically were enriched in oocyte meiosis and cell cycle pathways through re-analysis of DAVID. Moreover, the mRNA and protein levels of CDK1, CDC20, AURKA, and MCM4 were significantly increased in BC patients. In addition, knockdown of CDK1 and CDC20 by small interfering RNA remarkably suppressed cell migration and invasion in MCF-7 and MDA-MB-231 cells. In conclusion, our results suggested that CDK1, CDC20, AURKA, and MCM4 were reliable biomarkers of BC via bioinformatics analysis and experimental validation and may act as prospective targets for BC diagnosis and treatment.

Bidirectional role of reactive oxygen species during inflammasome activation in acrolein-induced human EAhy926 cells pyroptosis.

Acrolein, a known toxin in tobacco smoke, has been demonstrated to be associated with inflammatory cardiovascular diseases, such as atherosclerosis. However, the definite mechanism of acrolein-induced inflammation remains unclear. Here, we report that acrolein induces reactive oxygen species (ROS) production in EAhy926 cells. Additionally, acrolein induces EAhy926 cells' inflammatory response and pyroptosis by activating NOD-like receptor protein 3 (NLRP3) inflammasome. Also, acrolein-induced cytotoxicity could be attenuated by N-acetyl-L-cysteine (NAC). Furthermore, acrolein upregulates the level of autophagy which can be reversed by NAC. Notably, the present study also indicates that autophagy inhibited by inhibitor 3-methyladenine (3MA) and siAtg7 exacerbate acrolein-induced NLRP3 inflammasome activation and pyroptosis. In summary, acrolein induced cytotoxicity by ROS-mediated NLRP3 inflammasome activation, and ROS upregulates the level of autophagy to inhibit the NLRP3 inflammasome excessive activation, indicating the bidirectional role of ROS in acrolein-induced cellular inflammation. Our results may provide novel mechanistic insights into acrolein-induced cardiovascular toxicity.

Spotlight on NLRP3 Inflammasome: Role in Pathogenesis and Therapies of Atherosclerosis.

Inflammation is an intricate biological response of body tissues to detrimental stimuli. Cardiovascular disease (CVD) is the leading cause of death worldwide, and inflammation is well documented to play a role in the development of CVD, especially atherosclerosis (AS). Emerging evidence suggests that activation of the NOD-like receptor (NLR) family and the pyridine-containing domain 3 (NLRP3) inflammasome is instrumental in inflammation and may result in AS. The NLRP3 inflammasome acts as a molecular platform that triggers the activation of caspase-1 and the cleavage of pro-interleukin (IL)-1ß, pro-IL-18, and gasdermin D (GSDMD). The cleaved GSDMD forms pores in the cell membrane and initiates pyroptosis, inducing cell death and the discharge of intracellular pro-inflammatory factors. Hence, the NLRP3 inflammasome is a promising target for anti-inflammatory therapy against AS. In this review, we systematically summarized the current understanding of the activation mechanism of NLRP3 inflammasome, and the pathological changes in AS involving NLRP3. We also discussed potential therapeutic strategies targeting NLRP3 inflammasome to combat AS.

Pyrroloquinoline quinine ameliorates doxorubicin-induced autophagy-dependent apoptosis via lysosomal-mitochondrial axis in vascular endothelial cells.

The cardiotoxicity of doxorubicin (DOX) limits its clinical use in the treatment of a variety of solid tumors and malignant hematologic disease. However, the mechanism by which it causes cardiotoxicity is not fully understood. Apoptosis has been regarded as one of mechanisms underlying the cardiotoxic effects of DOX. In our study, we found that treatment of human umbilical vein endothelial cells (HUVECs) with DOX induced autophagy and apoptosis in a dose- and time-dependent manner. Treatment with DOX induced autophagy at earlier time (3 h), then lysosomal membrane permeabilization (LMP) altered after treatment for 12 h which followed by the release of cathepsin D (CTSD). Lysosome-associated membrane proteins-1 and -2 (LAMP1 and LAMP2) were decreased in DOX-treated cells. Additionally, DOX induced the collapse of mitochondrial transmembrane potential, reduction of translocase of the outer mitochondrial membrane-20 (TOM-20), and release of cytochrome c. Furthermore, autophagy inhibitor 3-MA relieved DOX-induced apoptosis as assessed by the expression of cleaved caspase-3, cleaved caspase-9 and TUNEL assay. CTSD inhibitor, pepstatin A, upregulated TOM-20 and suppressed the mitochondria release of cytochrome c as well as apoptosis under DOX stress. Pyrroloquinoline quinine (PQQ), a new B vitamin, ameliorated aforementioned phenomenon. In conclusion, our results suggested that DOX-induced apoptosis was autophagy-dependent via lysosomal-mitochondrial axis. PQQ had an ability to protect cell from autophagy-dependent apoptosis induced by DOX via lysosomal-mitochondrial axis to some extent. This study provided new mechanistic insight toward understanding the pathogenesis of DOX-induced cardiotoxicity and the protection effect of PQQ.

Acrolein induces NLRP3 inflammasome-mediated pyroptosis and suppresses migration via ROS-dependent autophagy in vascular endothelial cells.

Acrolein is a common environmental pollutant that has been linked to cardiovascular diseases, such as atherosclerosis (AS). Increasing evidence demonstrates that acrolein impairs the cardiovascular system by targeting vascular endothelial cells, but the underlying mechanisms haven't been completely elucidated. In human umbilical vein endothelial cells (HUVECs), we observed that acrolein treatment induced cell reactive oxygen species (ROS) generation, autophagy, pyroptosis and reduced cell migration. In addition, exposure to acrolein resulted in NLRP3 inflammasome activation as evidenced by cleavage of caspase-1 and downstream mature interleukin (IL)-1ß and IL-18 secretion. Knockdown of NLRP3 by small interfering RNA remarkably suppressed acrolein-induced pyroptosis and increased cell migration. Moreover, the scavenging ROS relieved the autophagy, NLRP3 inflammasome activation and pyroptosis. Furthermore, the role of autophagy in the acrolein-medicated pyroptosis and cell migration was investigated. In our study, 3-methyladenine (3-MA), an autophagy inhibitor, aggravated NLRP3 inflammasome activation, pyroptosis and decreased cell migration, rapamycin (Rapa), an autophagy inducer, alleviated aforementioned phenomenon under acrolein stress. Besides, we found damaged mitochondrion accentuated NLRP3 inflammasome and pyroptosis in acrolein-treated cells. In conclusion, it is possible that acrolein induced cell pyroptosis and suppressed cell migration via ROS-dependent autophagy. What's more, NLRP3 inflammasome activation plays a key role in this process.