Zhang W, Lawa R E, Hintona D R, Su Y, Couldwell W T
Department of Neurological Surgery, University of Southern California School of Medicine, Los Angeles 90033, USA.
Cancer Lett. 1995 Sep 4;96(1):31-5. doi: 10.1016/0304-3835(95)03914-i.
The effect of hypericin, an antiviral agent and inhibitor of protein kinase C (PKC), on cell proliferation and programmed death was investigated in the human neuroblastoma cell line SK-N-SH. Hypericin induced significant growth inhibition in a dose-dependent manner demonstrated by a microculture tetrazolium (MTT) assay. DNA isolated from cells treated with hypericin at concentrations over 1 microM exhibited a 'ladder' pattern of oligonucleosome-sized fragments characteristic of apoptosis. Similarly, treatment of the cells with the PKC inhibitors staurosporine, tamoxifen or phorbol ester PMA for 72 h also resulted in apoptosis, suggesting that hypericin may be triggering an apoptotic signal in neuroblastoma cells, which at least in part may be mediated by the inhibition of PKC.
金丝桃素是一种抗病毒剂及蛋白激酶C（PKC）抑制剂，本研究在人神经母细胞瘤细胞系SK-N-SH中探讨了其对细胞增殖及程序性死亡的影响。通过微量培养四氮唑蓝（MTT）分析表明，金丝桃素以剂量依赖方式诱导显著的生长抑制。从用浓度超过1微摩尔的金丝桃素处理的细胞中分离的DNA呈现出凋亡特有的寡核小体大小片段的“梯形”模式。同样，用PKC抑制剂星形孢菌素、他莫昔芬或佛波酯PMA处理细胞72小时也导致凋亡，这表明金丝桃素可能在神经母细胞瘤细胞中触发凋亡信号，这至少部分可能是由PKC的抑制介导的。
