Here, we evaluated the impact of fangchinoline (FCN) to attenuate tumor growth and survival through modulation of oncogenic STAT3 signaling pathway using diverse tumor cell lines and a xenograft mouse model.
To evaluate the action of FCN on STAT3 cascade, protein levels were analyzed by Western blot analysis and electrophoretic mobility shift assay (EMSA). Translocation of STAT3 was detected by immunocytochemistry. Thereafter, FCN-induced ROS was measured by GSH/GSSG assay and H2DCF-DA. FCN-induced apoptosis was analyzed using Western blot analysis and flow cytometry for various assays. Finally, anti-cancer effects of FCN in vivo was evaluated in a myeloma model.
We noted that FCN abrogated protein expression levels of STAT3 and upstream signals (JAK1/2 and Src). In addition, FCN also attenuated DNA binding ability of STAT3 and its translocation into the nucleus. It altered the levels of upstream signaling proteins, increased SHP-1 levels, and induced substantial apoptosis in U266 cells. FCN also promoted an increased production of reactive oxygen species (ROS) and altered GSSG/GSH ratio in tumor cells. Moreover, FCN effectively abrogated tumor progression and STAT3 activation in a preclinical myeloma model.
Overall, this study suggests that FCN may have a tremendous potential to alter abnormal STAT3 activation and induce cell death in malignant cells along with causing the suppression of pathogenesis and growth of cancer through a pro-oxidant dependent molecular mechanism.
这里,我们使用不同的肿瘤细胞系和异种移植小鼠模型,通过调节致癌STAT3信号通路,评估了fangchinoline(FCN)对减轻肿瘤生长和存活的影响.
为了评估FCN对STAT3级联的作用,蛋白质水平通过蛋白质印迹分析和电泳迁移率变化分析(EMSA)进行分析.通过免疫细胞化学检测STAT3的易位。此后,通过GSH/GSSG测定和H2DCF-DA测量FCN诱导的ROS。使用Western印迹分析和流式细胞术分析FCN诱导的细胞凋亡以进行各种测定。最后,在骨髓瘤模型中评估了FCN的体内抗癌作用.
我们注意到FCN消除了STAT3和上游信号(JAK1/2和Src)的蛋白质表达水平。此外,FCN还减弱了STAT3的DNA结合能力及其易位到细胞核中。它改变了上游信号蛋白的水平,增加SHP-1水平,并诱导U266细胞大量凋亡。FCN还促进了肿瘤细胞中活性氧(ROS)的产生增加,并改变了GSSG/GSH比率。此外,FCN在临床前骨髓瘤模型中有效地消除肿瘤进展和STAT3激活。
总的来说,这项研究表明,FCN可能具有改变异常STAT3激活和诱导恶性细胞细胞死亡的巨大潜力,并通过促氧化剂依赖性分子机制抑制癌症的发病和生长.