Reactive oxygen species (ROS) reduce the expression of BRAK/CXCL14 in human head and neck squamous cell carcinoma cells

The present study investigated the effects of oxidative stress induced by reactive oxygen species (ROS), such as hydrogen peroxide (H2O2) and hydroxyl radical (HO center dot), on the expression of both BRAK, which is also known as non-ELR motif angiostatic CXC chemokine ligand 14 (CXCL14), in head and neck squamous cell carcinoma (HNSCC) cells. When HNSCC cells were cultured in the presence of ROS, the expression of BRAK was significantly decreased whereas that of IL-8 was increased. Interestingly, the effects on the expression of both genes in HNSCC cells were much greater with HO center dot than with H2O2. The effects of ROS on both BRAK and IL-8 expression were attenuated by pre-treatment with N-acetyl-L-cysteine (NAG), epidermal growth factor receptor (EGER), and mitogen-activated protein kinase (MAPK) inhibitors. These results indicate that oxidative stress induced by H2O2 or HO center dot stimulates angiogenesis and tumuor progression by altering the gene expression of BRAK and IL-8 via the EGFR/MEK/ERK pathway in human HNSCC cells.