GL-9 peptide regulates gene expression of CD44 cancer marker and pro-inflammatory cytokine TNF-α in human lung epithelial adenocarcinoma cell line (A549).

In this study, we examined cytotoxic effect of GL-9 peptide on A459 cell line through studying the changes in TNF-α and CD44 gene expression and ROS production. Real-time PCR analysis showed that the treated A549 cells highly over expressed TNF-α, which was associated with a significant reduction of CD44 gene expression levels (p  <  0.05). ROS production rate was measured through the usage of DCFH-DA primer. Results demonstrated that GL-9 peptide could also induce cell death via ROS production. The effect of GL-9 peptide on human erythrocytes and leukocytes was analyzed. GL-9 peptide showed no significant toxic effect on human blood cells. Our results suggested that the GL-9 peptide as a potent natural agent could modulate gene expression of cancer cell markers.