Masuda H, Tanaka T, Tateishi M, Naito M, Tamai H
Department of Surgery, Kyushu Dental College, Japan.
Cancer Chemother Pharmacol. 2001;47(2):155-60. doi: 10.1007/s002800000198.
Superoxide anions (O2-) generated by cisplatin [cis-diamminedichloroplatinum (II), DDP] were determined by measuring the chemiluminescence from the luminescence probe, 2-methyl-6-[p-methoxyphenyl]-3,7-dihydroimidazo[1,2-a]pyrazin-3-one (methyl Cypridina luciferin analog, MCLA), in monolayer cultures of a human ovarian cancer cell line (A2780) in physiological saline at pH 7.0. In a time-course study, chemiluminescence of MCLA (C-MCLA) showed a peak level at 10 min and a background level at 60 min after the addition of DDP. The intensity of C-MCLA increased with increasing concentrations of DDP or MCLA in a limited concentration range, and was significantly correlated (r = 0.960) with the number of A2780 cells. DDP-induced C-MCLA was completely inhibited by the addition of the O2- scavenger, superoxide dismutase (SOD). However, SOD did not decrease DDP cytotoxicity in terms of clonogenic cell survival. These findings suggest that DDP generates extracellular O2-, probably by interaction with the cellular membrane in A2780 cells, and O2- does not lead to cellular damage.
通过在pH 7.0的生理盐水中对人卵巢癌细胞系（A2780）的单层培养物中测量发光探针2-甲基-6-[对甲氧基苯基]-3,7-二氢咪唑并[1,2-a]吡嗪-3-酮（甲基海萤荧光素类似物，MCLA）的化学发光，来测定顺铂[顺二氨二氯铂（II），DDP]产生的超氧阴离子（O2-）。在一项时间进程研究中，添加DDP后，MCLA的化学发光（C-MCLA）在10分钟时显示出峰值水平，在60分钟时显示出背景水平。在有限的浓度范围内，C-MCLA的强度随DDP或MCLA浓度的增加而增加，并且与A2780细胞数量显著相关（r = 0.960）。添加O2-清除剂超氧化物歧化酶（SOD）可完全抑制DDP诱导的C-MCLA。然而，就克隆形成细胞存活而言，SOD并未降低DDP的细胞毒性。这些发现表明，DDP可能通过与A2780细胞中的细胞膜相互作用产生细胞外O2-，并且O2-不会导致细胞损伤。
