目的:研究三环癸基苯并恶唑(TDB)是否通过p300介导的FOXO乙酰化调节肝癌细胞的增殖和凋亡。
方法:测序,腺病毒,在人肝癌细胞株SMMC-7721中进行慢病毒转染,并通过Tunel检测细胞凋亡,Hoechst,和流式细胞术。线粒体形态学的TEM,MTT对细胞增殖能力、蛋白质印迹,和PCR检测蛋白水平和mRNA变化。
结果:测序分析和细胞实验证实,TDB可以促进FOXO3表达的上调。TDB以剂量依赖性方式诱导FOXO3上调,促进了p300和Bim的表达,并增强FOXO3的乙酰化和去磷酸化,从而促进细胞凋亡。p300通过Bim和其他蛋白质促进癌细胞凋亡,而HAT增强FOXO3的磷酸化并抑制细胞凋亡。FOXO3的过表达可以增加外凋亡途径的表达(FasL,TRAIL),内源性凋亡途径(Bim),和蛋白水平的乙酰化,抑制细胞增殖和凋亡能力,而FOXO3沉默或p300突变可部分逆转细胞凋亡。在过表达FOXO3的肿瘤组织中,TDB干预可以进一步增加肿瘤细胞中p53和caspase-9蛋白的表达,导致细胞凋亡过程中线粒体膜完整性的丧失,信号转导过程中细胞质的释放,caspase-9的激活和生长的协同抑制。
结论:TDB通过激活p300介导的FOXO3乙酰化诱导SMMC-7721细胞增殖抑制和凋亡。
OBJECTIVE: To investigate whether tricyclic decylbenzoxazole (TDB) regulates liver cancer cell proliferation and apoptosis through
p300-mediated FOXO acetylation.
METHODS: Sequencing, adenovirus, and lentivirus transfection were performed in human liver cancer cell line SMMC-7721 and apoptosis was detected by Tunel, Hoechst, and flow cytometry. TEM for mitochondrial morphology, MTT for cell proliferation ability, Western blot, and PCR were used to detect protein levels and mRNA changes.
RESULTS: Sequencing analysis and cell experiments confirmed that TDB can promote the up-regulation of FOXO3 expression. TDB induced FOXO3 up-regulation in a dose-dependent manner, promoted the expression of
p300 and Bim, and enhanced the acetylation and dephosphorylation of FOXO3, thus promoting apoptosis.
p300 promotes apoptosis of cancer cells through Bim and other proteins, while HAT enhances the phosphorylation of FOXO3 and inhibits apoptosis. Overexpression of FOXO3 can increase the expression of exo-apoptotic pathways (FasL, TRAIL), endo-apoptotic pathways (Bim), and acetylation at the protein level and inhibit cell proliferation and apoptotic ability, while FOXO3 silencing or
p300 mutation can partially reverse apoptosis. In tumor tissues with overexpression of FOXO3, TDB intervention can further increase the expression of p53 and caspase-9 proteins in tumor cells, resulting in loss of mitochondrial membrane integrity during apoptosis, the release of cytoplasm during signal transduction, activation of caspase-9 and synergistic inhibition of growth.
CONCLUSIONS: TDB induces proliferation inhibition and promotes apoptosis of SMMC-7721 cells by activating
p300-mediated FOXO3 acetylation.