Chien Ching-Ming, Yang Sheng-Huei, Yang Chun-Chieh, Chang Long-Sen, Lin Shinne-Ren
Faculty of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung, Taiwan, ROC.
Cell Biochem Funct. 2008 Jan-Feb;26(1):111-8. doi: 10.1002/cbf.1420.
Cardiotoxin III (CTX III), a basic polypeptide with 60 amino acid residues isolated from Naja naja atra venom, has been reported to have anticancer activity. The molecular effects of CTX III on HL-60 cells were dissected in the present study. We found that the antiproliferative action of CTX III on HL-60 cells was mediated through apoptosis, as characterized by an increase of sub G1 population, DNA fragmentation and poly(ADP-ribose) polymerase (PARP) cleavage. Upregulation of Bax, downregulation of Bcl-2, the release of mitochondrial cytochrome c to cytosol and the activations of capase-9 and -3 were noted, while CTX III had no appreciable effect on the levels of Bcl-X(L) and Bad proteins. Moreover, c-Jun N-terminal kinase (JNK) was activated shortly after CTX III treatment in HL-60 cells. Consistently, the SP600125 compound, an anthrapyrazolone inhibitor of JNK, suppressed apoptosis induced by CTX III. As expected, this JNK inhibitor also attenuated the modulation of Bax and Bcl-2, as well as the cytosolic appearance of cytochrome c and the activation of caspase-3 and caspase-9 that induced by CTX III. These findings suggest that CTX III can induce apoptosis in HL-60 cells via the mitochondrial caspase cascade and the activation of JNK is critical for the initiation of the apoptotic death of HL-60 cells.
心脏毒素III（CTX III）是一种从眼镜蛇毒中分离出的含有60个氨基酸残基的碱性多肽，据报道具有抗癌活性。本研究剖析了CTX III对HL-60细胞的分子作用。我们发现CTX III对HL-60细胞的抗增殖作用是通过凋亡介导的，其特征是亚G1期细胞群体增加、DNA片段化以及聚（ADP-核糖）聚合酶（PARP）裂解。观察到Bax上调、Bcl-2下调、线粒体细胞色素c释放到细胞质以及caspase-9和-3激活，而CTX III对Bcl-X(L)和Bad蛋白水平没有明显影响。此外，在HL-60细胞中用CTX III处理后不久c-Jun氨基末端激酶（JNK）被激活。一致地，SP600125化合物，一种JNK的蒽吡唑啉酮抑制剂，抑制了CTX III诱导的凋亡。正如预期的那样，这种JNK抑制剂也减弱了CTX III诱导的Bax和Bcl-2的调节，以及细胞色素c的细胞质出现和caspase-3和caspase-9的激活。这些发现表明CTX III可通过线粒体caspase级联反应诱导HL-60细胞凋亡，并且JNK的激活对于HL-60细胞凋亡死亡的起始至关重要。
