Regulatory effect of NOX-4 on PI3K signaling pathway in TGF-β1-in-duced collagen Ⅰ synthesis from lung cancer cells / 中国病理生理杂志

ABSTRACT

AIM:To investigate the regulatory effect of NADPH oxidase-4 (NOX-4) on PI3K signaling path-way in transforming growth factor-β1 (TGF-β1)-induced collagen type Ⅰ (collagen Ⅰ) synthesis from lung cancer cells and the mechanisms. METHODS:Human lung cancer A549 cells were cultured in vitro and stimulated with TGF-β1. The ex-pression of NOX family and collagen family at mRNA and protein levels as well as the PI3K class Ⅰ catalytic subunits and the activation of PI3K signaling pathway was measured. A549 cells were pre-treated with NOX-4 inhibitor diphenyleneiodo-nium (DPI), and the expression of collagen Ⅰ at mRNA level as well as the PI3K class Ⅰ catalytic subunits and the activa-tion of PI3K signaling pathway was measured upon TGF-β1 stimulation. RESULTS:TGF-β1 stimulated the expression of NOX-4 and collagen Ⅰ at mRNA and protein levels as well as the expression of PIK3CD and the activation of PI3K signaling pathway at a dose- and time-dependent manner. NOX-4 inhibitor DPI partly reversed TGF-β1-induced collagen Ⅰ expres-sion. Inhibition of NOX-4 down-regulated the degree of TGF-β1-stimulated activation of PI3K signaling pathway without effect on the expression of PIK3CD. CONCLUSION:NOX-4 participates in TGF-β1-induced collagen Ⅰ synthesis from lung cancer cells via regulating the activation of PI3K signaling pathway. TGF-β1/NOX-4/PI3K signaling pathway axis acts as a regulatory role in collagen Ⅰ synthesis from lung cancer cells.