Enhancement of radiosensitivity of lung adenocarcinoma using a decoction from the Fuzhengzengxiao formula.

ABSTRACT

OBJECTIVE: To study the effects of a decoction of Fuzhengzengxiao formula on lung adenocarcinoma regarding the inflammatory protein S100A9 known to enhance cancer cell sensitivity. METHODS: A nude mouse model of human lung adenocarcinoma was established. The mice were randomly divided into four groups using the random number table method: Group I, control; Group II, treatment with a decoction of the Fuzhengzengxiao formula alone; Group III, treatment with radiotherapy alone; and Group IV, treatment with radiotherapy plus a decoction of Fuzhengzengxiao formula. When the tumor body was 1 cm3 in diameter, the tumor bearing mice in Groups III and IV were irradiated at a single dose of 10 Gy and the tumor inhibition rate was evaluated. The expression of S100A9 was determined using Western blotting and q-PCR (Real-time Quantitative PCR Detecting System). The sensitivity of cells containing RNAi S100A9 to radiotherapy was evaluated using the Click multiple target model,and the cell cycle was analyzed using flow cytometry. RESULTS: Relative to the control group, the expression of S100A9 in the tumors in each treatment group was decreased, especially in Group IV. The sensitizing enhancement ratio (SER) Dq was > 1 after RNAi S100A9; it decreased the surviving fraction after a 2 Gy dose exposure,and also the D0 and Dq of the tumor cells; in addition, the radiosensitivity of G2/M cells was significantly increased. CONCLUSION: The decoction of the Fuzhengzengxiao formula downregulated the expression of S100A9 in lung adenocarcinoma cells.