Department of Oncogenomics, Academic Medical Center, University of Amsterdam, Meibergdreef 15, PO Box 22700, 1105 AZ Amsterdam, The Netherlands.
Eur J Cancer. 2012 Nov;48(16):3093-103. doi: 10.1016/j.ejca.2012.01.037. Epub 2012 Feb 25.
Genomic aberrations of key regulators of the apoptotic pathway have hardly been identified in neuroblastoma. We detected high BCL2 mRNA and protein levels in the majority of neuroblastoma tumours by Affymetrix expression profiling and Tissue Micro Array analysis. This BCL2 mRNA expression is strongly elevated compared to normal tissues and other malignancies. Most neuroblastoma cell lines lack this high BCL2 expression. Only two neuroblastoma cell lines (KCNR and SJNB12) show BCL2 expression levels representative for neuroblastoma tumours. To validate BCL2 as a therapeutic target in neuroblastoma we employed lentivirally mediated shRNA. Silencing of BCL2 in KCNR and SJNB12 resulted in massive apoptosis, while cell lines with low BCL2 expression were insensitive. Identical results were obtained by treatment of the neuroblastoma cell lines with the small molecule BCL2 inhibitor ABT263, which is currently being clinically evaluated. Combination assays of ABT263 with most classical cytostatics showed strong synergistic responses. Subcutaneous xenografts of a neuroblastoma cell line with high BCL2 expression in NMRI nu/nu mice showed a strong response to ABT263. These findings establish BCL2 as a promising drug target in neuroblastoma and warrant further evaluation of ABT263 and other BCL2 inhibiting drugs.
在神经母细胞瘤中,凋亡途径的关键调节因子的基因组异常几乎没有被发现。我们通过 Affymetrix 表达谱和组织微阵列分析,在大多数神经母细胞瘤肿瘤中检测到高 BCL2 mRNA 和蛋白水平。与正常组织和其他恶性肿瘤相比,这种 BCL2 mRNA 表达显著升高。大多数神经母细胞瘤细胞系缺乏这种高 BCL2 表达。只有两种神经母细胞瘤细胞系(KCNR 和 SJNB12)显示出代表神经母细胞瘤肿瘤的 BCL2 表达水平。为了验证 BCL2 作为神经母细胞瘤的治疗靶点,我们采用了慢病毒介导的 shRNA。在 KCNR 和 SJNB12 中沉默 BCL2 导致大量细胞凋亡,而低 BCL2 表达的细胞系则不敏感。用小分子 BCL2 抑制剂 ABT263 处理神经母细胞瘤细胞系也得到了相同的结果,该抑制剂目前正在临床评估中。ABT263 与大多数经典细胞毒药物的组合测定显示出强烈的协同反应。在 NMRI nu/nu 小鼠中具有高 BCL2 表达的神经母细胞瘤细胞系的皮下异种移植对 ABT263 表现出强烈的反应。这些发现确立了 BCL2 作为神经母细胞瘤中一种有前途的药物靶点,并证明了进一步评估 ABT263 和其他 BCL2 抑制药物的必要性。