Diagnostic potential of NRG1 in benign nerve sheath tumors and its influence on the PI3K-Akt signaling and tumor immunity.

OBJECTIVE: Benign nerve sheath tumors (BNSTs) present diagnostic challenges due to their heterogeneous nature. This study aimed to determine the significance of NRG1 as a novel diagnostic biomarker in BNST, emphasizing its involvement in the PI3K-Akt pathway and tumor immune regulation. METHODS: Differential genes related to BNST were identified from the GEO database. Gene co-expression networks, protein-protein interaction networks, and LASSO regression were utilized to pinpoint key genes. The CIBERSORT algorithm assessed immune cell infiltration differences, and functional enrichment analyses explored BNST signaling pathways. Clinical samples helped establish PDX models, and in vitro cell lines to validate NRG1's role via the PI3K-Akt pathway. RESULTS: Nine hundred eighty-two genes were upregulated, and 375 downregulated in BNST samples. WGCNA revealed the brown module with the most significant difference. Top hub genes included NRG1, which was also determined as a pivotal gene in disease characterization. Immune infiltration showed significant variances in neutrophils and M2 macrophages, with NRG1 playing a central role. Functional analyses confirmed NRG1's involvement in key pathways. Validation experiments using PDX models and cell lines further solidified NRG1's role in BNST. CONCLUSION: NRG1 emerges as a potential diagnostic biomarker for BNST, influencing the PI3K-Akt pathway, and shaping the tumor immune microenvironment.

[Study on antibacterial properties of titanium metallic surface due to synergistic action of micro/nano-structure and antimicrobial peptides].

Objective: To investigate the effects of micro/nano-structure and antimicrobial peptides (AMPs) on antibacterial properties for titanium (Ti) metal surface. Methods: Ti disks were treated via sandblasted large-grit acid-etched (SLA) and alkali-heat treatment (AHT) to build the micor/nano-structure, on which AMPs were spin-coated with a certain amount (10, 30, 50, 70, and 90 µg). Scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) were used to observe the surface structure and characterize the surface elements (i.e. contents of C, N, O, and Ti). Ti disks loaded with AMPs of difference amounts were co-cultured with Staphylococcus aureus ( S. aureus) for 24 hours. After that, the formation and dimension of antibacterial circle were measured. Furthermore, the Ti disks treated with different approaches (untreated, SLA treatment, SLA+THA treatment, and loaded with 90 µg AMPs) were co-cultured with S. aureus and Escherichia coli ( E.coli) for 3 hours, bacterial adhesion on the disks were evaluated by using SEM. The antibacterial performances in solution were quantitatively evaluated by immersing the Ti disks in bacterial solutions and measuring the absorbance ( A) values. Results: It was found that the nanoporous structure could be easily constructed by SLA+AHT approach. After spin-coating AMPs, the nanopores with the diameter less than 200 nm were almost covered. According to the element analysis, with the increase of AMPs, the C content gradually increased; the N content was not detected until AMPs amount reached 70 µg on the disks. The diameter of antibacterial circle clearly depended on the AMPs amount. The Ti disks loaded with 90 µg AMPs had significantly larger antibacterial circles than the other Ti disks ( P<0.05). Based on the SEM observation, the Ti disks loaded with 90 µg AMPs has the least bacterial attachment compared with the other Ti disks ( P<0.05). The A value of bacterial solution immersed with the Ti disks loaded with 90 µg AMPs was much lower than the other Ti disks ( P<0.05). Conclusion: The approach of micro/nano-structure and AMPs can improve the antibacterial properties of Ti metal surface.