姜黄素抑制 Wnt信号通路对人胰腺癌细胞增殖凋亡的影响

摘要

Curcumin is the active ingredient of turmeric and is a non-toxic, diferuloyl methane compound.Many evidences resulted from MTT assays and Flow cytometric analysis performed in our lab show that curcumin inhibit the proliferation and induce apoptosis of pancreatic cancer cells,SW1990, in concentration-dependenced pattern. Our Western Blot Assay indicated that curcumin is a effective inhibitor, which interrupts Wnt/β-catenin signaling more effectively with dosage increasing.For reaching the goal of this project, we hope to better understand why curcumin regulates cell growth and the mechanism of Wnt/β-catenin in regulating cancer cell growth in pathogenesis of tumor.Methods:MTT assay was used to detect the growth of cell.The Flow cytometric analysis was performed to evaluate the cell apoptosis .Western Blot was applied to test the level ofβ-catenin.PCR was used to detect the expression of downstream target genes, such as c-myc、VEGF、cyclinD1 .Results: Curcumin is able to inhibit proliferation and induce apoptosis of pancreatic cancer cell lines,SW1990, in a dosage-dependent manner. Curcumin is able to down-regulate the level of cytoplasmic protein β-catenin and the expression of downstream target genes.Conclusion: Curcumin inhibits the growth and induces apoptosis of human pancreatic cancer lines, SW1990, by down-regulating the canonical Wnt/β-catenin.%目的：研究姜黄素对经典Wnt信号通路活性的调控作用，探讨姜黄素在体外对人胰腺癌细胞SW1990增殖凋亡、β-catenin蛋白表达以及下游相关靶基因表达的影响．方法：应用MTT法检测不同浓度姜黄素（20μmol/L、40μmol/L、60μmol/L、80μmol/L、100μmol/L）对人胰腺癌细胞SW1990增殖的抑制作用，用流式细胞仪分析细胞的凋亡率，用Western Blot方法检测姜黄素对β-catenin蛋白表达的影响，用半定量PCR法检测靶基因c-myc、VEGF和cyclinD1在不同浓度姜黄素作用后表达情况的变化．结果：姜黄素作用于人胰腺癌细胞SW1990后，细胞增殖的水平明显下降，凋亡率升高，且呈剂量依赖性．Western Blot结果显示姜黄素能降低胞质蛋白β-catenin的水平．姜黄素抑制SW1990细胞内Wnt信号通路下游靶基因c-myc、VEGF以及cyclinD1的表达水平．结论：姜黄素能抑制胰腺癌细胞的增殖并促进凋亡（ apoptosis），其机制与姜黄素下调经典Wnt信号通路中核心蛋白β-catenin的水平有关．