Effect of Endostar Combined with Radiotherapy on the Expression of Aquaporin 1 and Hypoxia-Inducible Factor-1 Alpha mRNA and Growth of Mice with Lewis Lung Cancer

Objective: To explore the effect of Endostar combined with radiotherapy on the mRNA expression of aquaporin 1 (AQP1) which mediated transmembrane transport of oxygen and hypoxia-inducible factor-1α (HIF-1α) in tumor-bearing mice with Lewis lung cancer. Methods: Thirty-two tumor-bearing mice were randomly divided into four groups: control group, Endostar group, radiation therapy group, and Endostar combined with radiotherapy group. After treatment, the tumor growth curve was calculated, and the real time PCR was used to detect the different expression of AQP1 and HIF-1α mRNA in each group. Results: Compared with that in control group, the expression of AQP1 mRNA had no changes in Endostar group (P0.05), decreased in radiotherapy group (P0.05), and increased in Endostar combined with radiotherapy (P0.05). Compared with control group, the expression of HIF-1α mRNA had no changes in Endostar group (P0.05), and was lower both in radiotherapy group and Endostar combined with radiotherapy group (both P0.05). There existed negative correlation between the expression of AQP1 and HIF-1α mRNA (r=-0.58,P0.01). Conclusion: Endostar combined with radiotherapy may enhance the tumor killing effect of radiation therapy through increasing AQP1 mRNA expression and inhibiting the HIF-1α mRNA expression, which enhances the oxygen uptake of cells, thereby increases the killing effect of radiation on tumor cells.