姜黄素抑制MGMT基因表达增强恶性胶质瘤对替莫唑胺化疗的敏感性

Curcumin downregulation of MGMT expression to enhance the chemosensitivity of temozolomide on maligant glioblastoma

目的 探讨姜黄素对高水平O6甲基鸟嘌呤DNA甲基转移酶（MGMT）的调控作用及其对恶性胶质瘤化疗敏感性的影响。方法 通过实时荧光定量PCR（qRT-PCR）测定姜黄素、替莫唑胺单药和二者联合对MGMT表达阳性恶性胶质瘤C6及U87细胞株、复发或耐药恶性胶质瘤原代细胞MGMT表达水平的影响。CCK-8检测细胞增殖变化，流式细胞检测细胞凋亡的变化。结果 与姜黄素（C6：0.64±0.03；U87：0.63±0.06；原代细胞：0.51±0.07）、替莫唑胺（C6：0.53±0.06；U87：0.51±0.04；原代细胞：0.79±0.03）单药比较，姜黄素、替莫唑胺二者联合（C6：0.14±0.01；U87：0.12±0.03；原代细胞：0.29±0.02）能明显降低C6及U87细胞株、复发或耐药恶性胶质瘤原代细胞株中MGMT的表达，组间差异具有统计学意义（C6：F=23.675，P=0.006；U87：F=29.021，P=0.001；原代细胞株：F=25.534，P=0.001）。与姜黄素、替莫唑胺单药比较，二者联合均能抑制细胞的增殖，半数抑制浓度（IC50）值降低，差异具有统计学意义（C6：F=6.731，P=0.012；U87：F=17.321，P=0.008；原代细胞株：F=18.857，P=0.007）。姜黄素和替莫唑胺二者联合作用后细胞的凋亡率较单药作用后明显增加，组间差异具有统计学意义（C6：F=25.871，P=0.001；U87：F=6.847，P=0.009；原代细胞株：F=36.641，P=0.000）。结论 姜黄素与替莫唑胺能协同降低MGMT的表达，增强恶性胶质瘤对替莫唑胺的化疗敏感性，为替莫唑胺耐药的恶性胶质瘤的治疗提供新的思路和方法。

ObjectiveTo explore the roles of curcumin in regulating high level O6methylguanineDNA methyltransferase （MGMT） expression and the chemosensitivity of gliomas cells to temozolomide （TMZ） in malignant gliomas. MethodsThe expressions of MGMT were detected in C6 and U87 cell lines and primary malignant gliomas cell by qRTPCR. The cell proliferation was analyzed after added in signal curcumin, signal TMZ, curcumin combined with TMZ in cells by CCK8 assay. The cell apoptosis rate was detected by flow cytometry. ResultsCompared with single curcumin （C6： 0.64±0.03; U87： 0.63±0.06; primary cell： 0.51±0.07） and single TMZ （C6： 0.53±0.06; U87： 0.51±0.04; primary cell： 0.79±0.03）, curcumin combined with TMZ （C6： 0.14±0.01; U87： 0.12±0.03; primary cell： 0.29±0.02） could significantly reduce the expression of MGMT in C6, U87 cell lines and primary cell line （C6： F=23.675, P=0.006; U87： F=29.021, P=0.001; primary cell： F=25.534, P=0.001）. The combination of curcumin and TMZ could significantly inhibit the cells proliferation, decrease the halfinhibition concentration （IC50） value （C6： F=6.731, P=0.012; U87： F=17.321, P=0.008; primary cell： F=18.857, P=0.007）. The apoptosis rate of the cells was significantly increased after the combined action of curcumin and TMZ （C6： F=25.871, P=0.001; U87： F=6.847, P=0.009; primary cell： F=36.641, P=0.000）. ConclusionSynergistic effect of curcumin and TMZ can reduce the expression of MGMT and increase the chemosensitivity of TMZ to malignant glioma, and provide new strategy and methods for the treatment of malignant glioma.