Hoffschir F, Ricoul M, Lemieux N, Estrade S, Cassingena R, Dutrillaux B
DSV-DPTE-LCG, Centre d'Etudes Nucléaires de Fontenay-aux-Roses, France.
Int J Cancer. 1992 Aug 19;52(1):130-6. doi: 10.1002/ijc.2910520123.
A comparative study of chromosomal rearrangements occurring in 4 independent clones obtained from SV40-transformed cornea and skin human fibroblasts was performed. Rearrangements principally affect some constitutive heterochromatin and, to a lesser degree, telomeric regions. This results in multiple exchanges between a limited number of chromosome structures, i.e., in jumping translocations. Such rearrangements occur even at early passages and some of them give rise to clonal rearrangements that accumulate at late passages. This process is responsible for progressive modification of the karyotypes, principally characterized by deletion of a number of chromosome segments. Thus, clonal rearrangements are selected among many others not occurring at random. The selective pressure retaining clonal rearrangement seems to be similar for the 4 independent clones, since selection of the derivative chromosomes leads to the same imbalances, whatever the origin of the clone. This sequence of events recalls that of human solid tumors, since jumping rearrangements are generally observed in pre-malignant conditions or in low-grade malignancies, whereas clonal rearrangements leading to typical imbalances are detected in more advanced malignant tumors.
对从SV40转化的人角膜和皮肤成纤维细胞获得的4个独立克隆中发生的染色体重排进行了比较研究。重排主要影响一些组成型异染色质，在较小程度上影响端粒区域。这导致有限数量的染色体结构之间发生多次交换，即跳跃易位。这种重排在早期传代时就会发生，其中一些会导致克隆性重排在后期传代时积累。这一过程导致核型的渐进性改变，主要特征是一些染色体片段的缺失。因此，克隆性重排是从许多其他随机发生的重排中被选择出来的。保留克隆性重排的选择压力在这4个独立克隆中似乎是相似的，因为无论克隆的起源如何，衍生染色体的选择都会导致相同的失衡。这一系列事件让人想起人类实体瘤的情况，因为跳跃重排通常在癌前状态或低级别恶性肿瘤中观察到，而导致典型失衡的克隆性重排在更晚期的恶性肿瘤中被检测到。
