Introduction: The transcription factor forkhead box D3 (FoxD3) is a forkhead protein and serves as a transcriptional repressor. The functions of FoxD3 in embryogenesis and in the development of neural crest cells have been diversely studied. Its role associated with tumor development has attracted attention just in recent years. However, little is known about its regulation and functions in the tumorigenesis and progression of lung cancer.
Materials and methods: We did a pioneer study to identify the function of FoxD3 in lung cancer by knocking down FoxD3 expression in lung adenocarcinoma cell lines.
Results: The result showed that silencing FoxD3 in lung cancer cell lines stimulated cell growth and inhibited cell apoptosis. Through quantified PCR analysis, we observed marked gene expression increase of insulin-like growth factor receptor 1 and BRAF under the condition of FoxD3 silencing. In contrast, cell cycle negative regulator P21 expression decreased after FoxD3 silencing.
Conclusions: Our study is the first to identify the tumor suppressor function of FoxD3 in lung cancer.
Keywords: Apoptosis; FoxD3; Lung cancer; Proliferation.