Hwang Jooyeon, Kim Young-Youl, Huh Sungjin, Shim Junghee, Park Chan, Kimm Kuchan, Choi Dong Kug, Park Tae-Kyu, Kim Soonhag
National Genome Research Institute, NIH, Seoul, Korea.
Microbiol Immunol. 2005;49(4):331-42. doi: 10.1111/j.1348-0421.2005.tb03737.x.
Zeocin, a member of the bleomycin/phleomycin family of antibiotics, is known to bind DNA and to induce apoptosis in cervical cancer cells, but the mechanism underlying this apoptotic response is poorly understood. The present study was undertaken to elucidate time-dependent serial transcript patterns in the HeLa cervical carcinoma cell line, following treatment with Zeocin. The HeLa cell proliferation rate was found to gradually decrease following Zeocin exposure, in a time-and dose-dependent manner. RNA transcript level measurements, for time-dependent serial gene expression profiling, were determined at 0, 6, 12, 18 and 24 hr using a 0.5 k apoptosis functional microarray chip. Further statistical analysis, using a significance test at a 95% confidence level, for transcripts with a greater than 2-fold change on the array chips, identified 49 up-regulated and 57 down-regulated genes. Our gene expression profile data indicate that Zeocin treatment induces an initial release of cytochrome c, the down-regulation of Bcl-X (L), ENDOG, DAXX and MDM2, and the up-regulation of CASP and BID. This suggests that a p53-independent mitochondrial caspase cascade pathway is primarily involved in Zeocin-induced apoptosis. Such caspasedependent cytotoxic activity also implies that this cell death pathway occurs via the caspase 8 and BID genes. However, disruption of either FAS or TNFR1 signaling did not interfere with the Zeocin induced apoptotic response in our experimental system. We hypothesize that Zeocin could be active against cervical cancer cell resistance to conventional chemotherapy and postulate that Zeocin is a novel candidate for the development of new chemotherapeutic treatments of gynecological cancers.
博来霉素（Zeocin）是博来霉素/腐草霉素家族抗生素的一员，已知其可与DNA结合并诱导宫颈癌细胞凋亡，但其凋亡反应的潜在机制尚不清楚。本研究旨在阐明博来霉素处理后，人宫颈癌细胞系HeLa中随时间变化的连续转录模式。发现HeLa细胞增殖率在博来霉素处理后呈时间和剂量依赖性逐渐降低。使用0.5k凋亡功能微阵列芯片，在0、6、12、18和24小时测定RNA转录水平，用于时间依赖性连续基因表达谱分析。进一步的统计分析，使用95%置信水平的显著性检验，对阵列芯片上变化大于2倍的转录本进行分析，确定了49个上调基因和57个下调基因。我们的基因表达谱数据表明，博来霉素处理诱导细胞色素c的初始释放、Bcl-X（L）、ENDOG、DAXX和MDM2的下调以及CASP和BID的上调。这表明p53非依赖性线粒体半胱天冬酶级联途径主要参与博来霉素诱导的凋亡。这种半胱天冬酶依赖性细胞毒性活性也意味着这种细胞死亡途径通过半胱天冬酶8和BID基因发生。然而，在我们的实验系统中，FAS或TNFR1信号的破坏并不干扰博来霉素诱导的凋亡反应。我们假设博来霉素可能对宫颈癌细胞对传统化疗的耐药性有活性，并推测博来霉素是开发妇科癌症新化疗治疗方法的新候选药物。
