Journal of Medicinal Food, 2013, 16(2):139-46.

Induction of Apoptosis in HeLa Cells via Caspase Activation by Resveratrol and Genistein

Vanessa Hörmann, et al

Rumbaugh-Goodwin Institute for Cancer Research, Nova Southeastern University, Fort Lauderdale, Florida, USA

Selectively inducing apoptosis in cancer cells is a much desired strategy when tolerance toward side effects is minimal during chemotherapy. In our search for natural products that can induce apoptosis in human cervical cancer cells (HeLa), we selected resveratrol and genistein for our study. We conducted several experiments to test whether genistein can synergistically enhance the apoptotic potential of resveratrol at doses lower than the usual cytotoxic dose. Both resveratrol and genistein were able to induce apoptosis by enhancing the activities of caspase-9 and caspase-3 by themselves and also in combination. After 24 h of exposure to resveratrol and genistein, individually or in combination, lowered mitochondrial membrane potential was observed in HeLa cells. In addition, the mitochondrial membrane potential in HeLa cells was decreased, forcing JC-1 to stay in the monomeric form. The monomeric JC-1(5,5',6,6' -tetrachloro-1,1',3,3'-tetraethyl benzimedazolyl carbocyanine iodide) emitted green fluorescence. In the control group, the color of the fluorescence was red due to aggregation of JC-1 in the physiological pH. The treatment groups exhibited DNA fragmentation as the hallmark of apoptotic nuclear features. We also detected an obvious decrease in the level of HDM2 gene expression after both individual and combination treatments with resveratrol and genistein. Our findings suggest that resveratrol and genistein when combined can induce apoptosis at doses lower than usual doses, through the activation of caspases cascade, and by decreasing the expression of HDM2.

美国《药膳杂志》，2013年2月

在HeLa 细胞中通过白藜芦醇和金雀异黄素激活半胱氨酸蛋白酶来诱导细胞凋亡

凡妮莎 霍曼，等

美国佛罗里达州诺瓦东南大学古德温癌症研究所

当在化疗期间对副作用的耐受性最小时，选择性地诱导肿瘤细胞凋亡是一种更期望的方法。在我们寻找的可以诱导人体宫颈癌细胞 (HeLa) 细胞凋亡的天然产品中，我们选择了白藜芦醇和金雀异黄素用于我们的研究。我们进行了几个实验来测试当剂量低于通常的细胞毒性剂量时，金雀异黄素是否可以协同增强白藜芦醇的凋亡潜力。白藜芦醇和金雀异黄素，通过单独或者联合增强半胱氨酸蛋白酶-9 和半胱氨酸蛋白酶-3 的活性，能够诱导细胞凋亡。在接触白藜芦醇与金雀异黄素24 小时以后，单独或组合，在 HeLa 细胞中观察到降低的线粒体膜电位。此外，HeLa 细胞的线粒体膜电位被降低，迫使 JC-1以单体形式保留。JC-1单体发出绿色荧光。在对照组中，在生理pH值时JC-1的聚合导致荧光的颜色为红色。治疗组表明 DNA 碎片是凋亡核的特征标志。我们也发现在用白藜芦醇与金雀异黄素单独和组合治疗时，HDM2 基因表达的水平明显下降。我们的研究结果表明，当剂量低于通常剂量时，白藜芦醇和金雀异黄素联合使用时可以诱导细胞凋亡通过半胱氨酸蛋白酶叶栅的活化和 HDM2 表达的下降。