ICAM1 Knockout Cell Lysate

Background Ewing's sarcoma (ES) is a kind of malignant tumor, which often occurs in the long bone, pelvis, and other bone tissues, as well as some soft tissues. It often occurs in children and adolescents, second only to osteosarcoma and rhabdomyosarcoma. In the past 30 years, little progress has been made on the genomic mechanism of ES metastasis. Methods The gene expression sequence of ES metastasis samples was compared with that of primary tumor samples to obtain differentially expressed genes (DEGs). Subsequently, we annotated the gene functions and enriched pathways of DEGs. Additionally, the protein and protein interaction network were constructed to screen key genes that can lead to the metastasis in ES. Then, cell and molecular biology experiments were conducted to verify the results obtained from the bioinformatics analysis. Finally, we assessed the correlation of expression between the key genes EWSR and FLI1, and conducted a survival analysis of ICAM1. Results Our study revealed 153 DEGs. Of these, 82 (53.59%) were upregulated and the remaining 71 (46.41%) were downregulated. The bioinformatics analysis showed that ICAM1 was the key gene leading to the invasion and metastasis of ES. Through cell biology and molecular biology experiments, inactivation of ICAM1 inhibited the metastasis of ES cells. The survival and correlation analyses showed that ICAM1 was a risk factor in patients with ES, and that ICAM1 expression was correlated with EWSR and FLI1 expression. Conclusion Our study shows that inactivation of ICAM1 inhibits metastasis and improves the prognosis of ES. Additionally, our findings provide a better understanding of the underlying mechanisms of metastatic ES, a basis for an accurate diagnosis, and therapeutic targets for ES patients.

Background Atopic dermatitis (AD) represents the most common inflammatory skin disorder in children showing massive infiltration of immune cells. The colonization of AD-afflicted skin by Staphylococcus aureus and S. aureus-derived extracellular vesicles (SEVs) has been associated with AD pathogenesis; however, the molecular mechanism underlying SEV-mediated inflammatory responses remains unclear. Objective We investigated how SEVs can mediate inflammatory responses in AD pathogenesis by examining the effect of SEVs on human dermal microvascular endothelia cells (HDMECs). Methods HDMECs were treated with SEVs, and the expression of cell adhesion molecules or cytokines was assessed using RT-qPCR, Western blot or cytokine array analyses. The receptor for SEVs and related signalling molecules in HDMECs were addressed and verified via gene knockdown or inhibitor experiments. The recruitment assay of human THP-1 monocytic cells on HDMECs was performed after SEV treatment in the presence or absence of the verified receptor or signalling molecule. Results SEVs, but not other gram-positive bacteria-derived extracellular vesicles, directly activated HDMECs by increasing the expression of cell adhesion molecules (E-selectin, VCAM1 and ICAM1) and that of IL-6, the inflammatory cytokine; consequently, they enhanced the recruitment of THP-1 monocytic cells to HDMECs. The SEV-induced HDMEC activation was dependent on Toll-like receptor 4 and the NF-kappa B signalling pathway, which was rapidly activated within 1 hour post-treatment and followed by an upregulation of cell adhesion molecules and IL-6 at later time-points. Moreover, SEV-mediated HDMEC responses were more rapid and intense than those induced by the same protein concentrations of S. aureus extracts. Conclusions & Clinical Relevance SEVs as proinflammatory factors could mediate immune cell infiltration in AD by efficiently inducing endothelial cell activation and monocyte recruitment, which may provide insights into alleviating the S. aureus-mediated onset or progression of AD and its phenotypes.