局部放射治疗诱发肿瘤患者外周血淋巴细胞HPRT基因突变与染色体畸变的研究

目的 研究放射治疗对患者外周血淋巴细胞HPRT基因突变的剂量效应关系，并与染色体畸变剂量效应关系进行比较。方法 选取未曾化疗、放疗的头颈肿瘤患者，分别于放疗前和照射后4、10、28、48和68Gy采集PBL进行微核率PBL染色体畸变和HPRT基因突变检测。结果 PBL胞质分裂阻滞微核率和PBLHPKT基因突变率在照射后均显著增加，并随剂量累积而增加；PBL染色体畸变率在照射10Gy后显著增高。染色体畸变类型以断片为主，并出现了双着丝粒体、环状染色体和微小体等畸变类型。结论 局部放射治疗对患者造成了明显的遗传损害，且与放射剂量有明显相关性。

Study on patient's peripheral blood lymphcytes (PBL) HPRT mutation and chromosome aberration inducedloy local radiotherapy

Objective To study the effect of radiotherapy on hypoxanthine-guanine phosphoribosy / transferase (HPRT) mutation of peripheral blood lymphcytes (PBL). And the correlation between dosage of radiotherapy and chromosome aberration. Methods 30 patients diagnosed as head neck carcinoma without radiotherapy or chemotherapy were selected, and we studied the micronuclei frequency(MNF), chromosome aberration(CA) and hprt mutation in PBL before radiotherapy and after radiated by 4, 10,28,48 and 68 Gy. Results The cytokinnesis-blocked MNF of PBL and PBL-hprt mutation increased significantly after radiation and depended on accumulation. The chromosome aberration of PBL increased significantly after radiated by 10Gy The major types of chromosome aberration were segements, as well as bisatellited dicentric extra small chromosome, Circled chromosome and munite. Conclusion Local radiotherapy can make remarkable heritage harm on patients, and the heritage damage are related to radiated dosage significantly.