Long-term molecular changes in WHO grade II astrocytomas following radiotherapy  

作　　者：Wei-Ying Yue Ke Sai Qiu-Liang Wu Yun-Fei Xia Su-Huan Yu Zhong-Ping Chen 

机构地区：[1]State Key Laboratory of Oncology in South China [2]Oepartment of Neurosurgery [3]Department of Pathology [4]Department of Radiation Oncology, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong 510060, P. R. China [5]Department of Neurosurgrey, Zhongnan Hospital, Wuhan University, Wuhan, Hubei 430077. P. R. China.

出　　处：《Chinese Journal of Cancer》2012年第3期159-165,共7页

摘　　要：Monitoring the long-term radiotherapy-associated molecular changes in low-grade gliomas(LGGs) facilitates the understanding of LGG response to radiotherapy.In this study,we used immunohistochemistry to analyze the expression of Ki-67,tumor protein P53(TP53),P21,and P27 in 8 paired WHO grade II astrocytoma samples.The interval between radiotherapy(RT) and the second surgery was more than 3 months in all cases.The average Ki-67 labeling index(LI) was 5.3% in pre-RT samples and 11.54% in post-RT samples.Ki-67 LI was higher in the primary tumors that underwent malignant transformation observed at the second surgery after radiation.Post-RT Ki-67 LI decreased in 2 cases with an interval of less than 12 months between RT and the second surgery.TP53 expression was found in 3 out of 4 pre-RT samples with malignant transformation and in 1 out of 4 pre-RT samples without malignant transformation.Post-RT TP53 increased in 2 cases in which increased expression of P21 or P27 was also observed.Our study suggests that radiotherapy can inhibit WHO grade II astrocytoma proliferation as reflected by Ki-67 LI,but the effect attenuates with time.In addition,there is a tendency of malignant transformation for WHO grade II astrocytomas with a high Ki-67 level or TP53 expression in initial samples.Monitoring the long-term radiotherapy-associated molecular changes in low-grade gliomas （LGGs） facilitates the understanding of LGG response to radiotherapy. In this study, we used immunohistochemistry to analyze the expression of Ki-67, tumor protein P53 （TP53）, P21, and P27 in 8 paired WHO grade II astrocytoma samples. The interval between radiotherapy （RT） and the second surgery was more than 3 months in all cases. The average Ki-67 labeling index （LI） was 5.3% in pre-RT samples and 11.54% in post-RT samples. Ki-67 LI was higher in the primary tumors that underwent malignant transformation observed at the second surgery after radiation. Post-RT Ki-67 LI decreased in 2 cases with an interval of less than 12 months between RT and the second surgery. TP53 expression was found in 3 out of 4 pre-RT samples with malignant transformation and in 1 out of 4 pre-RT samples without malignant transformation. Post-RT TP53 increased in 2 cases in which increased expression of P21 or P27 was also observed. Our study suggests that radiotherapy can inhibit WHO grade II astrocytoma proliferation as reflected by Ki-67 LI, but the effect attenuates with time. In addition, there is a tendency of malignant transformation for WHO grade II astrocytomas with a high Ki-67 level or TP53 expression in initial samples.

关 键 词：星形细胞 放疗 世卫组织 分子 P53基因 二级 时间间隔 世界卫生组织 

分 类 号：Q421[生物学—神经生物学] S896.3[生物学—生理学]