Cleaver J E, Char D, Charles W C, Rand N
Cancer Res. 1982 Apr;42(4):1343-7.
Fibroblasts from patients with hereditary retinoblastoma reportedly exhibit increased sensitivity to killing by X-rays. Although some human syndromes with similar or greater hypersensitivity to DNA-damaging agents (e.g., X-rays, ultraviolet light, and chemical carcinogens), such as xeroderma pigmentosum, are deficient in DNA repair, most do not have such clearly demonstrable defects in repair. Retinoblastoma cells appear to be normal in repairing single-strand breaks and performing repair replication after X-irradiation and also in synthesizing poly(adenosine diphosphoribose). Semiconservative DNA replication in these cells, however, is slightly more resistant than normal after X-irradiation, suggesting that continued replication of damaged parental DNA could contribute to the pathogenesis of the disease. This effect is small, however, and may be a consequence rather than a cause of the fundamental enzymatic abnormality in retinoblastoma that causes the tumorigenesis.
据报道，遗传性视网膜母细胞瘤患者的成纤维细胞对X射线杀伤的敏感性增加。虽然一些对DNA损伤剂（如X射线、紫外线和化学致癌物）具有相似或更高超敏反应的人类综合征，如着色性干皮病，存在DNA修复缺陷，但大多数在修复方面并没有如此明显可证实的缺陷。视网膜母细胞瘤细胞在修复单链断裂、X射线照射后进行修复复制以及合成聚（腺苷二磷酸核糖）方面似乎是正常的。然而，这些细胞中的半保留DNA复制在X射线照射后比正常情况略具抗性，这表明受损亲本DNA的持续复制可能有助于该疾病的发病机制。然而，这种影响很小，可能是视网膜母细胞瘤中导致肿瘤发生的基本酶异常的结果而非原因。
