Pradheepkumar C P, Panneerselvam N, Shanmugam G
Cancer Biology Division, School of Biological Sciences, Madurai Kamaraj University, Madurai, India.
Mutat Res. 2000 Jan 24;464(2):185-93. doi: 10.1016/s1383-5718(99)00179-5.
Cleistanthin A is a novel anticancer agent isolated from Cleistanthus collinus (Rox B). It caused chromatid aberrations in a dose dependent manner. However, the concentrations that induced the aberrations, neither affected viability nor induced DNA strand breaks. Only at higher concentrations and after long exposure, DNA strand breaks were observed. Cleistanthin A induced apoptosis in Chinese hamster ovary (CHO) cells, in cervical carcinoma (Si Ha) cells and in a p53 deficient cell line K562. Cleistanthin A-induced cell death was low in bcl-2 transfected cells. Cleistanthin A inhibited the incorporation of [3H]thymidine into DNA; however, it did not affect the transport of [3H]thymidine into these cells. These studies indicate that the cytotoxic effects of cleistanthin A are mediated by the inhibition of DNA synthesis, induction of DNA damage and apoptosis.
克利斯坦辛A是从印度乌檀中分离出的一种新型抗癌剂。它以剂量依赖的方式引起染色单体畸变。然而，诱导畸变的浓度既不影响细胞活力，也不诱导DNA链断裂。只有在较高浓度和长时间暴露后，才观察到DNA链断裂。克利斯坦辛A可诱导中国仓鼠卵巢（CHO）细胞、子宫颈癌细胞（Si Ha）和p53缺陷细胞系K562发生凋亡。在bcl-2转染细胞中，克利斯坦辛A诱导的细胞死亡较少。克利斯坦辛A抑制[3H]胸腺嘧啶核苷掺入DNA；然而，它不影响[3H]胸腺嘧啶核苷向这些细胞的转运。这些研究表明，克利斯坦辛A的细胞毒性作用是由抑制DNA合成、诱导DNA损伤和凋亡介导的。
