色素上皮衍生因子通过诱导肺癌血管正常化增强照射作用实验研究

目的 观察色素上皮衍生因子(PEDF)对肺癌血管正常化的作用及PEDF与X射线照射不同联合模式对肺癌的抑制作用。方法 采用免疫荧光的方法观测PEDF对肺癌血管正常化的作用并确定其正常化时间窗。建立Lewis肺癌C₅₇BL/6小鼠移植瘤模型,采用区组法随机分成4组,分别给予对照﹑PEDF﹑照射和照射联合PEDF处理,观察不同处理对小鼠移植瘤生长的作用。

Pigment epithelium-derived factor enhances radiation response by inducing vascular normalization in Lewis lung carcinoma

Objective To observe the effects of pigment epithelium-derived factor (PEDF) on vascular normalization in lung cancer and further investigate the combined effects of PEDF and radiation on the growth of lung cancer. Methods Immunofluorescent staining was used to observe the effects of PEDF on vascular normalization in lung cancer and determine the time window of vascular normalization. C₅₇BL/6 mice bearing Lewis lung carcinoma xenografts were prepared and divided into control group, PEDF group,radiation group, and PEDF+radiation groups. The growth of tumor xenografts was evaluated. ResultsPEDF reduced the vascular density and basement membrane thickness of Lewis lung carcinoma xenografts, increased the pericyte coverage of blood vessels, and reduced the hypoxic fraction of tumor xenografts. On days 3-7 of PEDF treatment, the PEDF group had a reduced fraction of hypoxic tumor cells compared with the control group (33.73%), and the lowest value for PEDF group was seen on day 3(20.79%). The time window of vascular normalization induced by PEDF was days 3-7. PEDF combined with radiation delivered on day 5 of PEDF treatment had a stronger inhibitory effect on tumor xenografts than radiation alone and PEDF combined with radiation delivered on day 1 of PEDF treatment. Conclusions PEDF can promote the vascular normalization in lung cancer and enhance the anti-lung cancer effect of radiation.