Zhu Yuan, Chen Zhen, Kim Su Na, Gan Chao, Ryl Tatsiana, Lesjak Michaela Silvia, Rodemerk Jan, Zhong Rong De, Wrede Karsten, Dammann Philipp, Sure Ulrich
Department of Neurosurgery and Spine Surgery, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany.
Center for Translational Neuro- & Behavioral Sciences (C-TNBS), University of Duisburg-Essen, 45147 Essen, Germany.
Cancers (Basel). 2022 Apr 28;14(9):2211. doi: 10.3390/cancers14092211.
Temozolomide (TMZ) is the first line of standard therapy in glioblastoma (GBM). However, relapse occurs due to TMZ resistance. We attempted to establish an acquired TMZ resistance model that recapitulates the TMZ resistance phenotype and the relevant gene signature. Two GBM cell lines received two cycles of TMZ (150 µM) treatment for 72 h each. Regrown cells (RG2) were defined as TMZ resistant cells. MTT assay revealed significantly less susceptibility and sustained growth of RG2 compared with parental cells after TMZ challenge. TMZ-induced DNA damage significantly decreased in 53BP1-foci reporter transduced-RG2 cells compared with parental cells, associated with downregulation of and . Flow cytometry revealed reduced G2/M arrest, increased EdU incorporation and suppressed apoptosis in RG2 cells after TMZ treatment. Colony formation and neurosphere assay demonstrated enhanced clonogenicity and neurosphere formation capacity in RG2 cells, accompanied by upregulation of stem markers. Collectively, we established an acute TMZ resistance model that recapitulated key features of TMZ resistance involving impaired mismatch repair, redistribution of cell cycle phases, increased DNA replication, reduced apoptosis and enhanced self-renewal. Therefore, this model may serve as a promising research tool for studying mechanisms of TMZ resistance and for defining therapeutic approaches to GBM in the future.
替莫唑胺（TMZ）是胶质母细胞瘤（GBM）的一线标准治疗药物。然而，由于对TMZ产生耐药性，肿瘤会复发。我们试图建立一种获得性TMZ耐药模型，该模型能够重现TMZ耐药表型及相关基因特征。两种GBM细胞系分别接受两个周期的TMZ（150µM）处理，每次处理72小时。重新生长的细胞（RG2）被定义为TMZ耐药细胞。MTT检测显示，与亲代细胞相比，TMZ攻击后RG2细胞的敏感性显著降低且持续生长。与亲代细胞相比，在53BP1焦点报告基因转导的RG2细胞中，TMZ诱导的DNA损伤显著减少，这与[基因名称1]和[基因名称2]的下调有关。流式细胞术显示，TMZ处理后，RG2细胞的G2/M期阻滞减少、EdU掺入增加且细胞凋亡受到抑制。集落形成和神经球检测表明，RG2细胞的克隆形成能力和神经球形成能力增强，同时干细胞标志物上调。总的来说，我们建立了一种急性TMZ耐药模型，该模型重现了TMZ耐药的关键特征，包括错配修复受损、细胞周期阶段重新分布、DNA复制增加、细胞凋亡减少和自我更新增强。因此，该模型可能成为未来研究TMZ耐药机制和确定GBM治疗方法的有前景的研究工具。
