Lacombe F, Belloc F, Dumain P, Puntous M, Lopez F, Bernard P, Boisseau M R, Reiffers J
Laboratoire d'Hématologie, CHR Bordeaux, Hôpital Haut-Lévêque, Pessac, France.
Cytometry. 1992;13(7):730-8. doi: 10.1002/cyto.990130709.
The cytotoxicity of ara-C derives from an inhibition of DNA synthesis after incorporation of ara-CTP into DNA. The rate of DNA synthesis can be determined from the amount of bromodeoxy-uridine (BrdUrd) incorporated into cells after a short exposure to BrdUrd. We developed a computer program to quantify the inhibition of the rate of DNA synthesis by analysis of the distribution of BrdUrd/DNA. Inhibition was evaluated in ara-C-sensitive and resistant cells after incubation with different doses of ara-C. An index of resistance to ara-C (RI) was expressed as the ratio of the amount of BrdUrd incorporated into S phase cells incubated with ara-C to that incorporated in the absence of ara-C. In the ara-C-sensitive and resistant HL60 cells, a linear relationship between RI and log ara-C concentration was observed. Small numbers of slightly resistant cells in mixtures of ara-C-sensitive and resistant cells could be determined using this method, making it suitable for clinical use to test the resistance of leukemic cells to ara-C.
阿糖胞苷的细胞毒性源于阿糖胞苷三磷酸（ara - CTP）掺入DNA后对DNA合成的抑制作用。DNA合成速率可通过短暂暴露于溴脱氧尿苷（BrdUrd）后掺入细胞的BrdUrd量来确定。我们开发了一个计算机程序，通过分析BrdUrd/DNA的分布来量化DNA合成速率的抑制情况。在用不同剂量的阿糖胞苷孵育后，对阿糖胞苷敏感和耐药细胞中的抑制作用进行了评估。阿糖胞苷耐药指数（RI）表示为与阿糖胞苷一起孵育的S期细胞中掺入的BrdUrd量与未加阿糖胞苷时掺入的BrdUrd量之比。在阿糖胞苷敏感和耐药的HL60细胞中，观察到RI与阿糖胞苷浓度的对数之间呈线性关系。使用该方法可以测定阿糖胞苷敏感和耐药细胞混合物中少量的轻度耐药细胞，使其适用于临床检测白血病细胞对阿糖胞苷的耐药性。
