Study on the biotinidase competitive inhibition constant in liver cancer, and its control by a sugar chain

1. 岩藻多糖对培养肝癌细胞系的抗肿瘤作用MTT实验结果显示，天然岩藻多糖对Hep G2细胞、Huh7细胞和正常肝细胞Chang细胞均有剂量依赖性的抑制作用。岩藻聚糖对细胞增殖的抑制作用在这三种细胞系中是相似的。大分子岩藻聚糖对Chang细胞和Huh7cells的抑制作用强于HepG2细胞。从HepG2细胞和Chang细胞的TUNEL染色来看，天然岩藻聚糖诱导细胞凋亡的程度较低。褐藻多糖对胎蛋白（肝癌的肿瘤标志物）生成的影响用不同浓度的褐藻多糖（0%、1%、2%、4%、10%、20%）处理hepg2细胞和Huh7cells，并在处理后24 h测定培养基a的胎蛋白水平。因此,摘要研究。以剂量依赖性方式降低HepG2细胞中α胎蛋白水平。与天然岩藻多糖和小分子岩藻多糖相比，大分子岩藻多糖主要降低α胎蛋白水平。天然岩藻胶、大分子岩藻胶和小分子岩藻胶均呈剂量依赖性地降低中α胎蛋白水平。免疫印迹法检测Huh7细胞α胎蛋白，发现天然岩藻聚糖对α胎蛋白有明显的抑制作用，而尼日利亚寡糖对α胎蛋白无明显抑制作用。另一方面，尼日利亚寡糖对α胎蛋白水平无显著影响。细胞和HepG2细胞。天然岩藻多糖对HepG2细胞和Huh7细胞生物素酶Ki活性的影响。这些数据表明岩藻糖聚糖可能通过调节生物素酶的酶动力学来显示抗肿瘤活性。

1. Anti-tumor effect of fucoidan on cultured hepatoma cell linesAccording to the results of MTT assay, natural fucoidan showed an inhibitory effect in dose dependent manner on Hep G2 cells, Huh7 cells, and Chang cells (normal hepatocyte). The inhibitory effect of fucoidan on cell proliferation is similar among these three cell lines. Large molecular fucoidan exerted a stronger inhibitory effect on Chang cells and Huh7cells than in HepG2 cells. Judging from TUNEL stain using HepG2 cells and Chang cells, apoptosis induction by natural fucoidan was milder than that by nigero-oligosaccharide.2. Effect of fucoidan on a fetoprotein production (a tumor marker for hepatocellular carcinoma)HepG2cells and Huh7cells were treated with various concentrations of fucoidan (0%, 1%, 2%, 4%, 10%, 20%), and medium a fetoprotein levels were determined after 24 h after treatment. Consequently, fucoidan. reduced medium α fetoprotein levels of HepG2 cells in a dose dependent manner. Comparing to native and small molecular fucoidans, large molecular fucoidan reduced predominantly α fetoprotein levels. Medium α fetoprotein levels were decrease by natural, large molecular and small molecular fucoidans in dose dependent manner. The western blotting of α fetoprotein in Huh7 cells showed marked reduction of α fetoprotein by natural fucoidan, but not by nigero-oligosaccharide. On the other hand, nigero-oligosaccharide did not decrease α fetoprotein levels of Huh? cells and HepG2 cells.3. Changes of biotinidase enzyme activity by fucoidanNatural fucoidan markedly decreased biotinidase Ki of HepG2 cells and Huh7 cells.These data suggested that fucoidan may demonstrate anti-tumor activity through modulating the enzyme kinetics of biotinidase.