Wang Ju-Bo, Dong Dan-Feng, Wang Mao-De, Gao Ke
Department of Neurosurgery, First Affiliated Hospital of Medical College, Xi'An Jiao-tong University, Xi'An, China E-mail :
Asian Pac J Cancer Prev. 2014;15(1):427-32. doi: 10.7314/apjcp.2014.15.1.427.
Isocitrate dehydrogenase (IDH) is of great importance in cell metabolism and energy conversion. IDH mutation in glioma cells is reported to be associated with an increased overall survival. However, effects biological behavior of therapy of gliomas are unclear. Here, we investigated the influence of wild-type and mutated IDH genes on glioma cell biological behavior and response to chemotherapy. Relevant mechanisms were further explored. We designed our study on the background of the IDHR132H mutation. Stable cell lines were constructed by transfection. The CCK-8 method was used to assess cell proliferation, flow cytometry for the cell cycle and cell apoptosis, and the transwell method for cell invasion. Nude mouse models were employed to determine tumorigenesis and sensitivity to chemotherapy. Western blotting was used to detect relevant protein expression levels. We found that overexpression of wild IDH1 gene did not cause changes in the cell cycle, apoptosis and invasion ability. However, it resulted in chemotherapy resistance to a high dose of temozolomide (TMZ) in vivo and in vitro. The IDH1 mutation caused cell cycle arrest in G1 stage and a reduction of proliferation and invasion ability, while raising sensitivity to chemotherapy. This may provide an explanation for the better prognosis of IDH1 mutated glioma patients and the relative worse prognosis of their wild-type IDH1 counterparts. We also expect IDH1 mutations may be optimized as new targets to improve the prognosis of glioma patients.
异柠檬酸脱氢酶（IDH）在细胞代谢和能量转换中具有重要意义。据报道，胶质瘤细胞中的IDH突变与总体生存率增加有关。然而，IDH对胶质瘤治疗生物学行为的影响尚不清楚。在此，我们研究了野生型和突变型IDH基因对胶质瘤细胞生物学行为及化疗反应的影响，并进一步探讨了相关机制。我们以IDHR132H突变为背景设计了本研究。通过转染构建稳定细胞系。采用CCK-8法评估细胞增殖，流式细胞术检测细胞周期和细胞凋亡，transwell法检测细胞侵袭。利用裸鼠模型确定肿瘤发生情况及对化疗的敏感性。采用蛋白质免疫印迹法检测相关蛋白表达水平。我们发现，野生型IDH1基因的过表达并未引起细胞周期、凋亡及侵袭能力的改变。然而，它导致体内外对高剂量替莫唑胺（TMZ）产生化疗耐药。IDH1突变导致细胞周期停滞在G1期，增殖和侵袭能力降低，同时提高了对化疗的敏感性。这可能为IDH1突变型胶质瘤患者预后较好而野生型IDH1患者预后相对较差提供了解释。我们也期望IDH1突变可作为改善胶质瘤患者预后的新靶点进行优化。
