Lejbkowicz F, Malik Z, Salzberg S
Department of Life Sciences, Bar-Ilan University, Ramat Gan, Israel.
Int J Cancer. 1988 Aug 15;42(2):279-83. doi: 10.1002/ijc.2910420223.
The Friend erythroleukemia cell line was used to study the binding and biological properties of the photosensitizer hematoporphyrin derivative (HPD) on a differentiating system. In addition, the effect of cholesterol hemisuccinate (CHS) enrichment of cell membranes on HPD activity was tested on the same cell system. Differentiation of Friend erythroleukemia cells (FLC) was induced with dimethyl sulfoxide (DMSO) and resulted in a decreased cell volume and an increased rate of hemoglobin synthesis as a function of the duration of DMSO treatment. Differentiated cells seem to bind less porphyrin than their undifferentiated counterparts. Thus, cells treated for 6 days with DMSO bound 30-40% less dye than an identical number of untreated FLC. In contrast, a similar inhibition of both DNA and protein synthesis by photoactivated HPD was evident in either DMSO-treated or untreated FLC. Enrichment of cell membranes with CHS led to the same degree of protection from the damaging activity of the photoactivated dye in both differentiated and undifferentiated FLC. The decreased binding of HPD to DMSO-treated FLC is most likely a result of a reduction in cell volume of differentiated cells and is not related to an intrinsic property of the differentiation process.
利用弗氏红白血病细胞系研究了光敏剂血卟啉衍生物（HPD）在分化系统中的结合及生物学特性。此外，在同一细胞系统中测试了细胞膜胆固醇半琥珀酸酯（CHS）富集对HPD活性的影响。用二甲基亚砜（DMSO）诱导弗氏红白血病细胞（FLC）分化，随着DMSO处理时间的延长，细胞体积减小，血红蛋白合成速率增加。分化细胞似乎比未分化细胞结合的卟啉更少。因此，用DMSO处理6天的细胞比相同数量未处理的FLC结合的染料少30%-40%。相比之下，光活化HPD对DNA和蛋白质合成的类似抑制在DMSO处理或未处理的FLC中均很明显。CHS对细胞膜的富集在分化和未分化的FLC中均导致对光活化染料损伤活性的同等程度的保护。HPD与DMSO处理的FLC结合减少很可能是分化细胞体积减小的结果，与分化过程的内在特性无关。
