Kriehuber R, Simkó M, Schiffmann D, Trott K R
Universität Rostock, FB Biologie, Lehrstuhl für Tierphysiologie, Germany.
Int J Radiat Biol. 1999 Aug;75(8):1021-7. doi: 10.1080/095530099139782.
In order to clarify the relationship between delayed reproductive death and radiation-induced genomic instability, the colony-forming efficiency of surviving, irradiated human squamous carcinoma cells and centromere positive as well as centromere negative micronuclei in surviving progeny were examined.
Colony-forming ability and micronucleus (MN) frequency in binucleated cells 24 h after the addition of cytochalasin B during 2 weeks of post-irradiation growth were determined in a squamous cell carcinoma cell line (SCL-II) of human origin. In addition, centromeres in micronuclei were detected using FISH.
In the human epithelial cell line used for these experiments, delayed reproductive death was pronounced and persisted for at least 2 weeks after irradiation. Although there is evidence for an increased rate of centromere positive micronuclei, but not of centromere negative micronuclei, arising during the first week of post-irradiation proliferation, this decreases later while the rate of delayed reproductive death remains elevated.
In the studied cell line, the observed delayed reproductive death is not closely related to the investigated criteria of radiation-induced genomic instability. This casts doubt on the common assumption that delayed reproductive death is a direct manifestation of radiation-induced genomic instability.
为了阐明延迟性生殖死亡与辐射诱导的基因组不稳定性之间的关系，研究了存活的受辐照人鳞状癌细胞的集落形成效率以及存活子代中着丝粒阳性和着丝粒阴性微核情况。
在人源鳞状细胞癌细胞系（SCL-II）中，测定了在辐照后2周生长期间添加细胞松弛素B 24小时后双核细胞的集落形成能力和微核（MN）频率。此外，使用荧光原位杂交（FISH）检测微核中的着丝粒。
在用于这些实验的人上皮细胞系中，延迟性生殖死亡明显，且在辐照后至少持续2周。虽然有证据表明在辐照后增殖的第一周内着丝粒阳性微核的发生率增加，但着丝粒阴性微核的发生率未增加，不过之后着丝粒阳性微核的发生率会下降，而延迟性生殖死亡的发生率仍保持在较高水平。
在所研究的细胞系中，观察到的延迟性生殖死亡与辐射诱导的基因组不稳定性的研究标准没有密切关系。这对延迟性生殖死亡是辐射诱导的基因组不稳定性的直接表现这一普遍假设提出了质疑。
