L-Asparaginase is a chemotherapeutic agent against various types of cancer due to its asparagine depleting ability. Previously, we have characterized a highly active and thermostable L-Asparaginase (TK1656) from Thermococcus kodakarensis and reported its anti-cancerous effects against acute lymphoblastic leukemia. In the current study, we report anti-proliferative and cytotoxic effects of TK1656 on glioblastoma cell line SF767. Our results showed that TK1656 reduced the proliferation of glioblastoma cells after 72 h in a dose-dependent manner while leaving Vero cells unaffected. The IC₅₀ of TK1656 against SF767 cells was calculated as 18 µg/mL by neutral red uptake assay. Phase-contrast microscopy showed pronounced morphological changes in TK1656 treated SF767 cells. Likewise, DAPI staining and DNA laddering showed that TK1656 has strong genotoxic effects on glioblastoma cells. The AO/EB dual staining pointed out the induction of apoptosis in TK1656 treated cells. Activation of Caspases 3, 6, and 8, after TK1656 treatment, further substantiated the notion of apoptosis mediated death in these cells. Furthermore, flow cytometry data showed that TK1656 treatment induced cell cycle arrest with an increased sub-G1 cell population and downregulation of CDK2 and CDK4. Altogether, our data revealed that TK1656 induces apoptosis and cell cycle arrest in glioblastoma cells. Our findings prompt further investigations to approve the use of TK1656 for the effective treatment of glioblastoma.

L-天冬酰胺酶由于其天冬酰胺消耗能力而成为针对各种类型癌症的化学治疗剂。以前，我们已经表征了来自柯达卡热球菌的高活性和热稳定的L-天冬酰胺酶（TK1656），并报道了其对急性淋巴细胞白血病的抗癌作用。在当前的研究中，我们报告了TK1656对胶质母细胞瘤细胞SF767的抗增殖和细胞毒性作用。我们的结果表明，TK1656在72小时后以剂量依赖的方式减少了胶质母细胞瘤细胞的增殖，同时使Vero细胞不受影响。IC ₅₀通过中性红吸收测定，针对SF767细胞的TK1656的定量为18 µg / mL。相差显微镜显示在TK1656处理的SF767细胞中形态发生了明显变化。同样，DAPI染色和DNA标记显示TK1656对胶质母细胞瘤细胞具有强大的遗传毒性作用。AO / EB双重染色指出了TK1656处理细胞的凋亡诱导。TK1656处理后，Caspases 3、6和8的激活进一步证实了这些细胞中凋亡介导的死亡的概念。此外，流式细胞仪数据表明，TK1656治疗诱导的细胞周期停滞伴随着亚G1细胞群的增加以及CDK2和CDK4的下调。总而言之，我们的数据显示TK1656诱导胶质母细胞瘤细胞凋亡和细胞周期停滞。