Human CD9 Stable Cell Line - LN-229

In recent years, CD9 has been extensively studied as a potential cancer biomarker. However, the biological role of CD9 in glioma remains unclear. Here, researchers explored the function and molecular mechanisms of CD9 in glioma. Analysis of the CGGA glioma database showed that patients with high CD9 expression had lower survival rates. The area under the ROC curve (AUC) of the GSE16011 dataset was greater than 0.7, indicating its high discriminative ability. Through gene set enrichment analysis (GSEA), immune correlation analysis, and CD9 mutation detection, CD9 was found to be most strongly associated with neutrophil infiltration, and patients in the CD9 high-expression group had higher rejection and TIDE scores, suggesting a lower likelihood of successful immunotherapy. Patients in the CD9 high-expression group were more sensitive to 81 drugs, suggesting its potential for treating glioma. Furthermore, CD9 overexpression in glioma may be related to gene mutations. In the glioblastoma cell line LN229, downregulation or upregulation of CD9 expression indicates that CD9 can positively regulate the migration ability of LN229 cells. In addition, compared with the control cell line, the expression of multiple marker genes such as VEGFR-2, TGF-β1, CASP1 and PI3K was downregulated in the CD9 knockdown cell line, while they were upregulated in the CD9 overexpression cell line.

To investigate the role of CD9 in the migration of glioblastoma cell lines, researchers constructed a CD9 knockdown LN229 cell line (Figure 1a). They then performed a Transwell migration assay to assess cell proliferation, showing that CD9 knockdown significantly reduced the migration ability of LN229 cells (Figure 1b, c). Furthermore, researchers transfected LN229 cells with a CD9 overexpression vector and a negative control, respectively. qRT-PCR analysis showed that CD9 expression levels were significantly upregulated in the CD9-overexpressing cell line (Figure 1d). The Transwell migration assay demonstrated that, compared to the negative control, CD9-overexpressing LN229 cells exhibited significantly enhanced migration ability (Figure 1e, f). Subsequently, researchers selected differentially expressed vascular endothelial growth factor receptor 2 (VEGFR-2), transforming growth factor β1 (TGF-β1), caspase 1 (CASP1), and phosphatidylinositol 3-kinase (PI3K) in the Hallmark pathway to investigate whether their gene expression levels were related to CD9. The results showed that, compared with the control LN229 cell line, all of the above genes were downregulated in the CD9 knockdown cell line, while all of the above genes were upregulated in the CD9 overexpression cell line (Figure 1g). All these results indicate that CD9 can promote the migration of glioblastoma cells by regulating multiple key pathways.

Figure 1. CD9 increased cell migration of glioblastoma cell lines. (Jiang J, Jiang B, Li W., 2024)