Tumor DNA methylation profiling of pediatric patients with adrenocortical tumors. Tumor DNA methylation profiling of pediatric patients with adrenocortical tumors

Abnormal DNA methylation contributes to tumor progression and is emerging as a prognostic marker in several types of cancers. To investigate whether DNA methylation is associated with Pediatric Adrenocortical Tumor (pACT) presentation and patient prognosis, we analyzed the methylation profile of 57 tumors (Illumina Infinium HumanMethylation850 BeadChip) and patients’ clinicopathological features and outcome. Overall design: DNA from 57 microdissected, fresh frozen tumor samples from pediatric patients was extracted using the QIAamp DNA Mini Kit (QIAGEN, Hilden, Germany) according to the manufacturer's instruction. DNA was commisioned to the University of Southern California Keck Genomics Platform (Los Angeles, CA, USA), where it was bisulfite-converted using tht EZ DNA methylation kit (Zymo Research, Irvine, CA) , as provided by the manufacturer, and hybridized to the Illumina Infinium HumanMethylation850 BeadChip as specified by Illumina.

异常DNA甲基化可促进肿瘤进展，目前正成为多种癌症的预后标志物。为探究DNA甲基化与儿童肾上腺皮质肿瘤（Pediatric Adrenocortical Tumor, pACT）的临床表现及患者预后是否相关，我们采用Illumina Infinium HumanMethylation850 BeadChip平台分析了57例肿瘤样本的甲基化谱，同时对患者的临床病理特征与转归进行了研究。实验整体设计：本研究从57例经显微切割的儿童患者新鲜冷冻肿瘤样本中提取DNA，操作严格遵循制造商说明书，使用QIAamp DNA Mini Kit（德国希尔德市凯杰（QIAGEN）公司）完成提取。随后将DNA样本委托至南加州大学凯克基因组学平台（美国加利福尼亚州洛杉矶市）进行后续实验：按照制造商提供的操作流程，使用EZ DNA甲基化试剂盒（美国加利福尼亚州欧文市Zymo Research公司）完成亚硫酸氢盐转化，再依照Illumina公司的标准规范，将样本杂交至Illumina Infinium HumanMethylation850 BeadChip芯片。