Wassermann K, Zwelling L A, Mullins T D, Silberman L E, Andersson B S, Bakic M, Acton E M, Newman R A
Cancer Res. 1986 Aug;46(8):4041-6.
The potential mechanisms of the extremely potent anthracycline analogue 3'-deamino-3'-(3-cyano-4-morpholinyl)doxorubicin (MRA-CN) have been compared with those of doxorubicin (DOX) by examination of drug effects on colony formation, macromolecular synthesis, DNA integrity, and ultrastructure of human leukemia cells in vitro. Following a 1-h exposure, MRA-CN was found to be 1400-fold more cytocidal than DOX which correlated with the drugs' inhibitory effects on DNA and total RNA synthesis. Treatment with MRA-CN resulted in a dose-dependent production of DNA interstrand cross-links as quantified by alkaline elution. One-h treatments with DOX or 3'-deamino-3'-(4-morpholinyl) doxorubicin (the non-cyano-containing analogue of MRA-CN) produced no DNA-DNA cross-links; rather they produced protein-concealed DNA single-strand breaks. After removal of MRA-CN, the DNA of KBM-3 cells displayed time-dependent fragmentation as indicated by rapid DNA filter elution during the pH 10 lysis step which preceded pH 12 elution. Within 4 h of MRA-CN exposure (10 nM, 1 h), 50% of the cellular DNA was in the lysis fraction. By 24 h, all the cellular DNA was in this fraction. MRA-CN (10 nM), 3'-deamino-3'-(4-morpholinyl)doxorubicin (1 microM), and actinomycin D (1 microM), but not DOX (3 mircroM), each produced distinctive nucleolar macrosegregation, indicating an effect on rRNA synthesis. The alpha-CN substituent on the morpholinyl moiety of MRA-CN appears to be responsible for the unique antitumor potency of this anthracycline. Nucleolar macrosegregation is probably associated with the morpholinyl moiety and is independent of the alpha-CN substituent.
通过检测药物对体外人白血病细胞集落形成、大分子合成、DNA完整性和超微结构的影响，对极有效的蒽环类类似物3'-脱氨基-3'-(3-氰基-4-吗啉基)阿霉素（MRA-CN）与阿霉素（DOX）的潜在作用机制进行了比较。暴露1小时后，发现MRA-CN的细胞杀伤作用比DOX强1400倍，这与药物对DNA和总RNA合成的抑制作用相关。用MRA-CN处理导致DNA链间交联呈剂量依赖性产生，通过碱性洗脱定量。用DOX或3'-脱氨基-3'-(4-吗啉基)阿霉素（MRA-CN的非氰基类似物）处理1小时未产生DNA-DNA交联；相反，它们产生了蛋白质掩盖的DNA单链断裂。去除MRA-CN后，KBM-3细胞的DNA显示出时间依赖性片段化，这在pH 12洗脱之前的pH 10裂解步骤中通过快速DNA滤膜洗脱得以体现。在暴露于MRA-CN（10 nM，1小时）4小时内，50%的细胞DNA存在于裂解部分。到24小时时，所有细胞DNA都在该部分。MRA-CN（10 nM）、3'-脱氨基-3'-(4-吗啉基)阿霉素（1 microM）和放线菌素D（1 microM），但不是DOX（3 microM），各自产生了独特的核仁大分离，表明对rRNA合成有影响。MRA-CN吗啉基部分上的α-氰基取代基似乎是这种蒽环类药物独特抗肿瘤效力的原因。核仁大分离可能与吗啉基部分相关，且与α-氰基取代基无关。
