蛋氨酸酶联合顺铂协同抑制人肺腺癌细胞GLC生长作用

Synergetic Inhibition Effects of Methioninase and Cisplatin against the Growth of Human Lung Adenocarcinoma Cell Line GLC

目的纯化重组蛋氨酸酶并探讨其联合化疗药物顺铂对人肺腺癌GLC细胞生长的协同抑制效应.方法对原核表达体系pGEX-4T-1-Met/Dh5a菌液破碎后上清过纯化柱(GST)纯化后,采用MTT比色法测定重组蛋氨酸酶与顺铂联合应用对GLC细胞增殖的抑制作用,采用金正均法计算q值判断两药合用是否具有协同作用.结果重组蛋氨酸裂解酶浓度为0.22 mg/mL,纯度达95%,活性为0.568 IU/mg.给药72 h后单用顺铂对GLC细胞抑制率为24.80%,单用蛋氨酸酶抑制率为27.49%,两药合用抑制率为66.80%.q=1.47>1.15,表现出明显协同作用.结论蛋氨酸酶及顺铂均有抑制GLC增殖作用,并且两者联合使用存在协同作用.

Objective To purify recombinant methioninase and investigate the synergetic inhibitory effect of methioninase and cisplatin on the proliferation of human lung adenocarcinoma cell line GLC. Methods Recombinant methioninase was purified with GST-column from supernatant after ultrasonic disruption of cultured Escherichia coli in the prokaryotic expression system pGEX-4T-1-Met/Dh5a. MTT assay was used to determine the inhibition rate of methioninase in combined with cisplatin on cell proliferation,and their synergistic effect was evaluated by using the q value judge method. Results The concentration of recombinant methionine cleaving enzyme was 0.22 mg/mL, the purity was 95%, and the activity was 0.568 IU/mg. After 72 h culturing, the inhibition rate of cisplatin methionine was 24.80%and 27.49%respectively,while the inhibition rate of the combined drugs was 66.80% （ =1.47〉1.15） which showed a significant synergistic effect. Conclusion Both methioninase and cisplatin have the inhibition effect,and the combined drugs display a significant synergistic effect on the proliferation of GLC.