Laboratory of Molecular Biomedicine, Institute of Bioscience, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
Toxicol In Vitro. 2011 Oct;25(7):1392-8. doi: 10.1016/j.tiv.2011.04.030. Epub 2011 May 15.
Thymoquinone (TQ), the active constituent of Nigella sativa or black cumin exhibited cytotoxic effects in several cancer cell lines. In this study, the cytotoxicity of TQ in human cervical squamous carcinoma cells (SiHa) was investigated. TQ was cytotoxic towards SiHa cells with IC50 values of 10.67 ± 0.12 and 9.33 ± 0.19 μg/mL as determined by MTT assay and trypan blue dye exclusion test, respectively, after 72 h of incubation. TQ was more cytotoxic towards SiHa cells compared to cisplatin. Interestingly, TQ was less cytotoxic towards the normal cells (3T3-L1 and Vero). Cell cycle analysis performed by flowcytometer showed a significant increase in the accumulation of TQ-treated cells at sub-G1 phase, indicating induction of apoptosis by the compound. Apoptosis induction by TQ was further confirmed by Annexin V/PI and AO/PI staining. Significant elevation of p53 and down-regulation of the anti-apoptotic Bcl-2 protein was found in the treated cells, without any changes in the expression of the pro-apoptotic Bax protein. In conclusion, thymoquinone from N. sativa was more potent than cisplatin in elimination of SiHa cells via apoptosis with down-regulation of Bcl-2 protein.
姜黄素（TQ）是黑孜然（Nigella sativa）或黑孜然的活性成分，对几种癌细胞系表现出细胞毒性作用。在这项研究中，研究了 TQ 对人宫颈鳞状癌细胞（SiHa）的细胞毒性。MTT 测定和台盼蓝染料排除试验分别在 72 h 孵育后测定，TQ 对 SiHa 细胞的 IC50 值分别为 10.67±0.12 和 9.33±0.19μg/mL。与顺铂相比，TQ 对 SiHa 细胞的细胞毒性更大。有趣的是，TQ 对正常细胞（3T3-L1 和 Vero）的细胞毒性较小。流式细胞仪进行的细胞周期分析显示，TQ 处理的细胞在亚 G1 期的积累明显增加，表明该化合物诱导细胞凋亡。TQ 诱导的细胞凋亡进一步通过 Annexin V/PI 和 AO/PI 染色得到证实。在处理的细胞中发现 p53 显著升高，抗凋亡 Bcl-2 蛋白下调，而促凋亡 Bax 蛋白的表达没有任何变化。总之，黑孜然中的姜黄素通过下调 Bcl-2 蛋白，比顺铂更有效地消除 SiHa 细胞，从而诱导细胞凋亡。
