半夏中一种抗癌蛋白的纯化及其抗癌活性研究

Purification and characterization of an anticancer activity protein from Pinellia ternata

经硫酸铵分级沉淀、疏水层析和DEAE离子交换层析3种方法从新鲜半夏块茎中分离纯化出一种具抗肿瘤作用的蛋白,命名为APPT,用MTT法、载瘤小鼠实验和流式细胞术研究其抗肿瘤作用.结果显示:APPT是一种分子量大小为12.09ku的糖蛋白,其含糖量为3.22%;MTT实验结果表明APPT对Sarcoma 180细胞有一定的细胞毒性,同时载瘤小鼠实验证明APPT能明显抑制载瘤小鼠中肿瘤的生长,当APPT处理剂量为0.85mg/kg、2.30mg/kg及3.25mg/kg体重时,其抑制率分别为15.6%、32.1%、36.2%;流式细胞仪结果显示APPT不能诱导Sarcoma 180细胞凋亡,却能抑制Sarcoma 180细胞DNA的合成起始并将大量细胞同步于G0/G1期.表明APPT是半夏总蛋白中具有抑癌活性的成分之一,APPT通过抑制肿瘤细胞DNA合成的起始进而阻止肿瘤细胞增殖而不是诱导细胞凋亡.

A kind of anticancer activity protein from Pinellia ternata(APPT) was purified by hydrophobic chromatography and DEAE-ion exchange chromatography.The result of MTT experiment showed that APPT had effect on the viability of Sarcoma 180 which depended on the concentration of APPT,and APPT apparently inhibited transplanted tumor in mice.Flow cytometric analysis demonstrated that APPT inhibited proliferation of Sarcoma 180 in a time-and dose-dependent manner through inhibiting the transition of G1/S and corresponding inducing G0/G1 cell cycle arrest.These results indicated that APPT was one of anti-tumor activity constituents in the total proteins of Pinellia ternata.