Al-Abboodi Ashwaq Shakir, Rasedee Abdullah, Abdul Ahmad Bustamam, Taufiq-Yap Yun Hin, Alkaby Wafaa Abd Alwahed, Ghaji Mostafa Saddam, Waziri Peter M, Al-Qubaisi Mothanna Sadiq
MAKNA-UPM, Cancer Research Laboratory, Institute of Bioscience, University Putra Malaysia, Serdang, Malaysia.
Basic Science Branch, Faculty of Dentistry, University of Al-Qadisiyah, Al Diwaniyah, Iraq.
Drug Des Devel Ther. 2017 Nov 23;11:3309-3319. doi: 10.2147/DDDT.S147626. eCollection 2017.
Dentatin (DEN) (5-methoxy-2, 2-dimethyl-10-(1, 1-dimethyl-2propenyl) dipyran-2-one), a natural compound present in the roots of Burm f, possesses pro-apoptotic and antiproliferative effects in various cancer cells. Because of its hydrophobicity, it is believed that its complexation with hydroxy-β-cyclodextrin (HPβCD) will make it a potent inhibitor of cancer cell growth. In the current work, the molecular mechanisms of apoptosis induced by DEN and DEN-HPβCD complex were demonstrated in human colon HT-29 cancer cells.
After the human colon HT-29 cancer cells were treated with DEN and DEN-HPβCD complex, their effects on the expression of apoptotic-regulated gene markers in mitochondria-mediated apoptotic and death receptor pathways were detected by Western blot analysis and reverse transcription polymerase chain reaction. These markers included caspases-9, 3, and 8, cytochrome c, poly (ADP-ribose) polymerase, p53, p21, cyclin A as well as the Bcl-2 family of proteins.
At 3, 6, 12, and 24 µg/mL exposure, DEN and DEN-HPβCD complex significantly affected apoptosis in HT-29 cells through the down-regulation of Bcl-2 and cyclin A in turn, and up-regulation of Bax, p53, p21, cytochrome c at both protein and mRNA levels. DEN and DEN-HPβCD complex also decreased cleaved poly (ADP-ribose) polymerase and induced caspases-3, -8, and -9.
Results of this study indicate that the apoptotic pathway caused by DEN and DEN-HPβCD complex are mediated by the regulation of caspases and Bcl-2 families in human colon HT-29 cancer cells. The results also suggest that DEN-HPβCD complex may have chemotherapeutic benefits for colon cancer patients.
齿孔酸（DEN）（5-甲氧基-2,2-二甲基-10-(1,1-二甲基-2-丙烯基)二氢吡喃-2-酮）是一种存在于缅甸安息香根中的天然化合物，在多种癌细胞中具有促凋亡和抗增殖作用。由于其疏水性，据信其与羟丙基-β-环糊精（HPβCD）络合后将成为癌细胞生长的有效抑制剂。在当前研究中，在人结肠HT-29癌细胞中证实了DEN和DEN-HPβCD复合物诱导凋亡的分子机制。
用人结肠HT-29癌细胞分别用DEN和DEN-HPβCD复合物处理后，通过蛋白质印迹分析和逆转录聚合酶链反应检测它们对线粒体介导的凋亡和死亡受体途径中凋亡调节基因标志物表达的影响。这些标志物包括半胱天冬酶-9、3和8、细胞色素c、聚（ADP-核糖）聚合酶、p53、p21、细胞周期蛋白A以及Bcl-2蛋白家族。
在3、6、12和24μg/mL暴露浓度下，DEN和DEN-HPβCD复合物通过依次下调Bcl-2和细胞周期蛋白A以及在蛋白质和mRNA水平上调Bax、p53、p21、细胞色素c，显著影响HT-29细胞的凋亡。DEN和DEN-HPβCD复合物还降低了裂解的聚（ADP-核糖）聚合酶水平，并诱导了半胱天冬酶-3、-8和-9。
本研究结果表明，DEN和DEN-HPβCD复合物引起的凋亡途径是由人结肠HT-29癌细胞中半胱天冬酶和Bcl-2家族的调节介导的。结果还表明，DEN-HPβCD复合物可能对结肠癌患者具有化疗益处。
