Santisteban M S, Brugal G
Equipe de Reconnaissance des Formes et de Microscopie Quantitative, Université Joseph Fourier, Grenoble, France.
Anal Cell Pathol. 1995 Jul;9(1):13-28.
This paper reports on quantitative in situ changes in chromatin structure that occur throughout the cell cycle of the human breast cancer epithelial cell line, MCF-7. Texture parameters were measured by image cytometry on nuclei stained by DNA specific fluorochromes. These parameters calculated from the co-occurrence and run length matrices of grey level images were previously shown to be related to condensation, organization and distribution of DNA. In some experiments, cells were triple stained for DNA/Ki-67/PCNA, and compartmentalization in the cycle was ascertained from the Ki-67/PCNA pattern expression. In these experiments, Hoechst dye was used to stain DNA. Chromatin of cells traversing G1 phase progressively decondensed and became homogeneously distributed. In addition, these G1 cells had more condensed chromatin than cells in G0 phase (as determined by Ki-67 negative staining). During the S and G2 phases, chromatin condensation took place and an increasing reticulated organization was quantified. Similar profile of changes in chromatin texture was found in experiments done with cells double stained by AT-specific Hoechst dye and the GC-specific mithramycin dye. GC-rich chromatin texture-associated parameters greatly varied comparing to those of AT-rich chromatin during the G0/G1 phase as well as in the first mid-S phase. Conversely, variation of the AT-associated parameters was much greater in the second half of S phase as compared to the GC-associated parameters that barely varied during this period. This study well establishes the correlation between in situ chromatin texture and proliferation state because the latter is assessed by proliferation-associated antigens. Moreover, changes in chromatin texture are independently ascribed to the AT- and GC-rich regions suggesting that these 2 types of chromatin are involved to different extents in transcriptional and replicational tasks.
本文报道了人类乳腺癌上皮细胞系MCF-7整个细胞周期中染色质结构的定量原位变化。通过图像细胞术对用DNA特异性荧光染料染色的细胞核测量纹理参数。这些从灰度图像的共生和游程长度矩阵计算得出的参数先前已被证明与DNA的凝聚、组织和分布有关。在一些实验中，对细胞进行DNA/Ki-67/PCNA三重染色，并根据Ki-67/PCNA模式表达确定细胞周期中的区室化。在这些实验中，使用Hoechst染料对DNA进行染色。处于G1期的细胞染色质逐渐解聚并均匀分布。此外，这些G1期细胞的染色质比G0期细胞（通过Ki-67阴性染色确定）更凝聚。在S期和G2期，染色质发生凝聚，并对日益增加的网状组织进行了定量。在用AT特异性Hoechst染料和GC特异性放线菌素D染料对细胞进行双重染色的实验中，发现了类似的染色质纹理变化情况。在G0/G1期以及S期前期，富含GC的染色质纹理相关参数与富含AT的染色质相比有很大差异。相反，与在此期间几乎没有变化的富含GC的参数相比，S期后半段富含AT的参数变化要大得多。这项研究很好地确立了原位染色质纹理与增殖状态之间的相关性，因为后者是通过增殖相关抗原评估的。此外，染色质纹理的变化独立归因于富含AT和富含GC的区域，这表明这两种类型的染色质在转录和复制任务中涉及的程度不同。
