The First Clinical Medical College of Lanzhou University, Lanzhou, Gansu, China.
Department of Obstetrics and Gynecology, The First Hospital of Lanzhou University, Lanzhou, Gansu, China.
J Gynecol Oncol. 2019 Sep;30(5):e77. doi: 10.3802/jgo.2019.30.e77.
Pseudolaric acid B (PAB) has been shown to inhibit the growth of various tumor cells, but the molecular details of its function are still unknown. This study investigated the molecular mechanisms by which PAB induces apoptosis in HeLa cells.
The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays were performed to investigate the effect of PAB treatment in various cervical cancer cell lines. Annexin V/propidium iodide staining combined with flow cytometry and Hoechst 33258 staining were used to assess PAB-induced apoptosis. Additionally, we performed bioinformatics analyses and identified a paired box 2 () binding site on the BAX promoter. We then validated the binding using luciferase and chromatin immunoprecipitation assays. Finally, western blotting assays were used to investigate PAB effect on the Wnt signaling and the involved signaling molecules.
PAB promotes apoptosis and downregulates expression in HeLa cells in a time- and concentration-dependent manner. binds to the promoter of and inhibits its expression; therefore, inhibition is associated with increased levels of , which induces apoptosis of HeLa cells via the mitochondrial pathway. Additionally, PAB inhibits classical Wnt signaling.
PAB effectively inhibits Wnt signaling and expression, and increases BAX levels, which induce apoptosis in HeLa cells. Therefore, PAB is a promising natural molecule for the treatment of cervical cancer.
蒲公英酸 B（PAB）已被证明能抑制多种肿瘤细胞的生长，但它的功能的分子细节仍不清楚。本研究探讨了 PAB 诱导 HeLa 细胞凋亡的分子机制。
采用 3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐（MTT）法研究 PAB 处理对各种宫颈癌细胞系的影响。采用 Annexin V/碘化丙啶染色结合流式细胞术和 Hoechst 33258 染色来评估 PAB 诱导的细胞凋亡。此外，我们进行了生物信息学分析，并鉴定了 BAX 启动子上的配对盒 2（）结合位点。然后我们使用荧光素酶和染色质免疫沉淀实验验证了结合。最后，通过 Western blot 实验来研究 PAB 对 Wnt 信号通路及其相关信号分子的影响。
PAB 以时间和浓度依赖的方式促进 HeLa 细胞凋亡和下调表达。与启动子结合并抑制其表达；因此，抑制与的水平升高有关，后者通过线粒体途径诱导 HeLa 细胞凋亡。此外，PAB 抑制经典的 Wnt 信号通路。
PAB 能有效抑制 Wnt 信号通路和的表达，增加 BAX 水平，从而诱导 HeLa 细胞凋亡。因此，PAB 是治疗宫颈癌的一种有前途的天然分子。
