[The Effect of Endostatin and Radiotherapy on Human Lung Cancer Cell Line A549 and the Impact of HIF-1 Expression after Therapy.].
BACKGROUND
It has been proven that radiotherapy can induce tumor cells over expressing HIF-1. The aim of this work is to investigate the effect of endostatin and radiotherapy on human lung cancer cell line A549 and the impact of HIF-1 expression after therapy.


METHODS
Analysed the cell proliferation periods of the A549 cells after treated by endostatin. The A549 cells were treated with endostatin (ES) and/or radiotherpy (RT), and then the cell growth inhibiting rate was detected by methyl thiazolyl tetrazolium (MTT), the expression of HIF-1 was determined by enzyme linked immunosorbent assay (Elisa).


RESULTS
Every treatments can inhibit the growth of A549 cells, but the cells treated with endostatin and radiotherapy were inhibited more obviously. Endostatin had the function of block cell periods on A549, it stoped the A549 cells at G2/M and S periods. Treatment of endostatin and radiotherapy can reduce the expression of HIF-1 induced by radiotherapy.


CONCLUSIONS
Endostatin was synergistical with the effect of radiotherapy on inhibiting the growth rate of the A549 cells. This synergism may come from: endostatin can make A549 cells accumulated in G2-M and S transition, thereby inhibiting the proliferation of the A549 cells. HIF-1 is a important factor in resistant of cemotherapy and radiotherapy. Endostatin can inhibite the producing of HIF-1 by cells itself or induced by radiation, so increasing the treatment effect of radiotherapy.
Zhang
Yanyan
Y
Department of Oncology, Wuhan University Renmin Hospital, Wuhan 430060, China.
Ge
Wei
W
Zhao
Juan
J
Zhao
Zhenyu
Z
Li
Changhu
C