Morales Andressa Gois, Pezuk Julia Alejandra, Brassesco María Sol, de Oliveira Jaqueline Carvalho, de Paula Queiroz Rosane Gomes, Machado Hélio Rubens, Carlotti Carlos Gilberto, Neder Luciano, de Oliveira Harley Francisco, Scrideli Carlos Alberto, Tone Luiz Gonzaga
Department of Genetics, University of São Paulo, Av. Bandeirantes, 3900, Bairro Monte Alegre, 14048-900, Ribeirão Preto, Sao Paulo, Brazil.
Childs Nerv Syst. 2013 Dec;29(12):2241-8. doi: 10.1007/s00381-013-2175-8. Epub 2013 Jun 2.
Glioblastoma (GBM) is a very aggressive and lethal brain tumor with poor prognosis. Despite new treatment strategies, patients' median survival is still lower than 1 year in most cases. The expression of the BUB gene family has demonstrated to be altered in a variety of solid tumors, pointing to a role as putative therapeutic target. The purpose of this study was to determine BUB1, BUB3, and BUBR1 gene expression profiles in glioblastoma and to analyze the effects of BUB1 and BUBR1 inhibition combined or not with Temozolomide and radiation in the pediatric SF188 GBM cell line.
For gene expression analysis, 8 cell lines and 18 tumor samples were used. The effect of BUB1 and BUBR1 inhibition was evaluated using siRNA. Apoptosis, cell proliferation, cell cycle kinetics, micronuclei formation, and clonogenic capacity were analyzed after BUB1 and BUBR1 inhibition. Additionally, combinatorial effects of gene inhibition and radiation or Temozolomide (TMZ) treatment were evaluated through proliferation and clonogenic capacity assays.
We report the upregulation of BUB1 and BUBR1 expression and the downregulation of BUB3 in GBM samples and cell lines when compared to white matter samples (p < 0.05). Decreased cell proliferation and colony formation after BUB1 and BUBR1 inhibition were observed, along with increased micronuclei formation. Combinations with TMZ also caused cell cycle arrest and increased apoptosis. Moreover, our results demonstrate that BUB1 and BUBR1 inhibition sensitized SF188 cells to γ-irradiation as shown by decreased growth and abrogation of colony formation capacity.
BUB1 and BUBR1 inhibition decreases proliferation and shows radiosensitizing effects on pediatric GBM cells, which could improve treatment strategies for this devastating tumor. Collectively, these findings highlight the potentials of BUB1 and BUBR1 as putative therapeutic targets for glioblastoma treatment.
胶质母细胞瘤（GBM）是一种极具侵袭性和致命性的脑肿瘤，预后较差。尽管有新的治疗策略，但在大多数情况下，患者的中位生存期仍低于1年。BUB基因家族的表达已证明在多种实体瘤中发生改变，表明其作为潜在治疗靶点的作用。本研究的目的是确定胶质母细胞瘤中BUB1、BUB3和BUBR1基因的表达谱，并分析在儿科SF188 GBM细胞系中，BUB1和BUBR1抑制联合或不联合替莫唑胺及放疗的效果。
用于基因表达分析的有8种细胞系和18个肿瘤样本。使用小干扰RNA（siRNA）评估BUB1和BUBR1抑制的效果。在抑制BUB1和BUBR1后，分析细胞凋亡、细胞增殖、细胞周期动力学、微核形成和克隆形成能力。此外，通过增殖和克隆形成能力测定评估基因抑制与放疗或替莫唑胺（TMZ）治疗的联合效果。
与白质样本相比，我们报告GBM样本和细胞系中BUB1和BUBR1表达上调，BUB3表达下调（p < 0.05）。观察到抑制BUB1和BUBR1后细胞增殖和集落形成减少，同时微核形成增加。与TMZ联合也导致细胞周期停滞和凋亡增加。此外，我们的结果表明BUB1和BUBR1抑制使SF188细胞对γ射线照射敏感，表现为生长减少和集落形成能力丧失。
抑制BUB1和BUBR1可降低增殖，并对儿科GBM细胞显示放射增敏作用，这可能改善这种毁灭性肿瘤的治疗策略。总体而言，这些发现突出了BUB1和BUBR1作为胶质母细胞瘤治疗潜在治疗靶点的潜力。
