Long-term molecular epidemiological studies on thyroid cancers around Chernobyl

为了弄清切尔诺贝利事故后迅速增加的儿童甲状腺癌的直接原因及其对健康的影响，我们在国外同行的基础上成功开展了分子流行病学联合研究项目。特别是我们可以与WHO、NCRP、EU等深入参与国际辐射安全项目，进一步加深对辐射风险分析和管理的认识。我们继续收集来自前苏联（白俄罗斯、乌克兰和俄罗斯）的辐射暴露受害者及其生物材料的数据，并提取DNA，对其进行进一步的snp分析，包括DNA损伤修复酶等主要靶基因。我们的研究结果表明，一些snp模式与辐射相关的甲状腺癌呈正相关，包括DNA损伤修复酶和抗癌基因。同时，我们在国际…更多的联合项目下，在切尔诺贝利组织库工作。通过对切尔诺贝利放射性相关甲状腺癌标本的病理变化进行分析，发现其不同年龄组的基因型-表型差异、潜伏期差异和组织学差异等临床病理特征。值得庆幸的是，从复发率和死亡率的角度来看，非放疗性甲状腺癌与放疗性甲状腺癌的临床预后没有差异，提示儿童甲状腺癌经过适当治疗后预后良好。现在，基因组广泛关联研究正在使用从切尔诺贝利收集的样本进行调查。最后，我们利用自己的成就，在积极参加世卫组织和其他国际会议的基础上，为修订辐射安全准则作出了贡献。除了外部辐射暴露的风险外，新生儿和儿童的放射性碘内照射选择性地和特异性地增加了辐射诱发甲状腺癌的风险。因此，我们的研究进展有望为核灾难预防措施和辐射安全标准准则提供基础数据，并具有重要的社会意义。少

In order to clarify the direct cause of childhood thyroid cancers rapidly increased after the Chernobyl accident and its health consequences, we have successfully performed the joint research projects on molecular epidemiology on a basis of overseas' counterparts. Especially we could deeply commit to the international radiation safety programs with WHO, NCRP and EU and further deepened our understanding of radiation risk analysis and management with them. We have continued the collection of data on radiation-exposed victims and their biomaterials from the former USSR (Belarus, Ukraine and Russia), and extracted the DNAs which were subjected to further analysis of SNPs including the major target genes such as DNA damage repairing enzymes. Our results indicated the positive association of some SNPs pattern with radiation-associated thyroid cancers including DNA damage repairing enzymes and anti-oncogenes. Simultaneously we have worked at the Chernobyl Tissue Bank under the international … More consortium program. Using the samples collected from Chernobyl, we have analyzed the pathological changes of radiation-associated thyroid cancers and found the clinico-pathological characteristics such as genotype-phenotype difference by its different aged group, latency difference and histological difference. Fortunately there are no clinical prognostic difference between non-radiation and radiation-induced thyroid cancers at the standpoint of recurrence rate and mortality, suggesting a fairly good prognosis of childhood thyroid cancers after appropriate therapy. Now the genome wide association study is under investigation using the samples collected from Chernobyl.In conclusion, we have contributed to the revision of radiation safety guidelines on a basis of active participation on WHO and other international meetings using our own achievement. Besides the risk of external radiation exposure, internal exposure by radioactive iodines to neonate and children selectively and specifically increased the risk of radiation-induced thyroid cancers. Therefore our research progress can be expected to contribute to fundamental data on preventive measures of nuclear disaster and radiation safety standard guidelines that are also socially of a great significance. Less