title: CpG oligodeoxyribonucleotide 7909 enhances radiosensitivity via downregulating Oct-4 expression in radioresistant lung cancer cells.
abstract: Radiotherapy is a powerful cure for local advanced non-small cell lung cancer. However, radioresistance and tumor relapse still occur in a high proportion of patients. Octamer-4 (Oct-4), a transcription factor of the POU family, plays a key role in maintaining chemoradioresistant properties and regulating cancer progression. In this study, we demonstrated that Oct-4 expression was significantly increased in radioresistant H460 (H460R) cell line. CpG oligodeoxyribonucleotide (CpG-ODN) 7909 sensitized H460R cells when combined with irradiation treatment. The clonogenic capacity was significantly decreased, and the values of D0 and Dq were lower than those of irradiation alone group. The sensitive enhancement ratio (SER) of D0 was 1.224. This combined treatment led to a dramatic reduction in Oct-4 expression in a dose-dependent manner and also showed increased percentage of cells in the radiosensitive G2/M phase relative to either treatment alone. These results identified that Oct-4 was involved in radioresistance. CpG-ODN 7909 could enhance radiosensitivity partly through downregulating Oct-4 expression in radioresistant lung cancer cells.
authors.affiliation: Department of Oncology, Fudan University, Shanghai, People's Republic of China.
authors.forename: Na
authors.initials: N
authors.lastname: Xing
authors.affiliation: Department of Oncology, Fudan University, Shanghai, People's Republic of China.
authors.forename: Tiankui
authors.initials: T
authors.lastname: Qiao
authors.affiliation: Department of Oncology, Fudan University, Shanghai, People's Republic of China.
authors.forename: Xibing
authors.initials: X
authors.lastname: Zhuang
authors.affiliation: Department of Oncology, Fudan University, Shanghai, People's Republic of China.
authors.forename: Sujuan
authors.initials: S
authors.lastname: Yuan
authors.affiliation: Department of Oncology, Fudan University, Shanghai, People's Republic of China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Center Laboratory, Jinshan Hospital, Fudan University, Shanghai, People's Republic of China.
authors.forename: Guoxiong
authors.initials: G
authors.lastname: Xu
keywords: CpG-ODN; Oct-4; TLR9; lung cancer; radiosensitivity