摘要目的 探讨低剂量辐射及低剂量联合大剂量辐射对人胶质瘤生长的影响.方法 以胶质瘤细胞株U251及荷人胶质瘤裸鼠移植瘤为研究对象,分别给予低剂量辐射和低剂量联合大剂量辐射,采用细胞计数、噻唑蓝(MTT)、流式细胞术等方法检测对细胞增殖的影响,通过汁算抑瘤率来观察低剂量辐射联合大剂量辐射对移植瘤生长的影响.结果 低剂量辐射后U251细胞计数、MTT及流式细胞术检测结果与假照组相比差异无统计学意义;大剂量辐射组及低剂量联合大剂量辐射组细胞增殖明显受抑,凋亡增多,细胞周期G2期阻滞,两组间差异无统计学意义;低剂量辐射联合大剂量辐射组与单独大剂量辐射组均对裸鼠移植瘤有明显的抑制作用,但联合照射组抑瘤作用更强;联合照射组与单纯大剂量辐射组相比,血液系统损伤有所减轻.低剂量辐射组与假照组相比肿瘤生长差异无统计学意义.结论 低剂量辐射对人胶质瘤细胞无直接的抑制作用、兴奋效应.不诱导对大剂量辐射适应性反应,但能够在对正常造血系统产生保护作用的基础上,增强大剂量辐射对荷瘤裸鼠移植瘤的抑瘤作用,这种协同抗肿瘤作用在去除细胞免疫影响后仍然存在.

abstractsObjective To detect the effect on the growth of human glioma cell U251 induced by low dose irradiation and low dose irradiation combined with large dose irradiation.Methods Human glioma cell line U251 and nude mice carried with human glioma were used.The tumor cells and the mice were treated with low dose,high dose,and low dose combined hish dose radiation.Cells growth curve.MTT and flow cytometry were used to detect the proliferation,cell cycle and apoptosis of the cells;and the tumor inhibition rate was used to assess the growth of tumor in vivo.Results After low dose irradiation.there was no difference between experimental group and control group in cell count.MTT and flow cytometry.Single high dose group and low dose combined high dose group beth show significanly the suppressing effect on tumor cells,the apoptosis increased and there was cell cycle blocked in C2 period,but there was no difference between two groups.In vivo apparent anti-tumor effect in high dose radiation group and the combining group was observed,and that was more significant in the combining group;the prior low dose radiation alleviated the injury of hematological system. There was no difference between single low dose radiation group and control.Conclusions There is no significant effect on human glioma cell induced by low dose radiation, and low dose radiation could not induce adaptive response.But in vivo experience.low dose radiation could enhance the anti-tumor effect of high dose radiation and alleviated the injury of hematological system.