Department of Biotechnology, Motilal Nehru National Institute of Technology Allahabad, Prayagraj, India.
Department of Surgical Oncology, King George Medical University, Lucknow, India.
J Gynecol Oncol. 2022 Jul;33(4):e49. doi: 10.3802/jgo.2022.33.e49. Epub 2022 Mar 23.
To correlate the genome-wide methylation signature of microRNA genes with dysregulated expression of selected candidate microRNA in tissue and serum samples of epithelial ovarian cancer (EOC) and control using quantitative reverse transcription polymerase chain reaction (qRT-PCR), and evaluation of EOC predictive value of candidate microRNA at an early stage.
We performed Methylated DNA Immunoprecipitation coupled with NGS (MeDIP-NGS) sequencing of 6 EOC and 2 normal tissue samples of the ovary. Expression of selected microRNA from tissue (EOC=85, normal=30) and serum (EOC=50, normal=15) samples was evaluated using qRT-PCR. We conducted bioinformatics analysis to identify the candidate miRNA's potential target and functional role.
MeDIP-NGS sequencing revealed hypermethylation of several microRNAs gene promoters. Three candidate microRNAs were selected (microRNA-34a, let-7f, and microRNA-31) from MeDIP-NGS data analysis based on log2FC and P-value. The relative expression level of microRNA-34a, let-7f, and microRNA-31 was found to be significantly reduced in early-stage EOC tissues and serum samples (p<0.0001). The receiver operating characteristic analysis of microRNA-34a, let-7f and miR-31 showed improved diagnostic value with area under curve(AUC) of 92.0 (p<0.0001), 87.9 (p<0.0001), and 85.6 (p<0.0001) and AUC of 82.7 (p<0.0001), 82.0 (p<0.0001), and 81.0 (p<0.0001) in stage III-IV and stage I-II EOC serum samples respectively. The integrated diagnostic performance of microRNA panel (microRNA-34a+let-7f+microRNA-31) in late-stage and early-stage serum samples was 95.5 and 96.9 respectively.
Our data correlated hypermethylation-associated downregulation of microRNA in EOC. In addition, a combined microRNA panel from serum could predict the risk of EOC with greater AUC, sensitivity, and specificity.
通过定量逆转录聚合酶链反应（qRT-PCR），将 miRNA 基因的全基因组甲基化特征与上皮性卵巢癌（EOC）组织和血清样本中选定候选 miRNA 的表达失调相关联，并评估候选 miRNA 在早期预测 EOC 的价值。
我们对 6 个 EOC 和 2 个卵巢正常组织样本进行了甲基化 DNA 免疫沉淀结合高通量测序（MeDIP-NGS）测序。使用 qRT-PCR 评估组织（EOC=85，正常=30）和血清（EOC=50，正常=15）样本中选定 miRNA 的表达。我们进行了生物信息学分析，以确定候选 miRNA 的潜在靶标和功能作用。
MeDIP-NGS 测序显示多个 miRNA 基因启动子呈超甲基化状态。基于 log2FC 和 P 值，从 MeDIP-NGS 数据分析中选择了三个候选 miRNA（miRNA-34a、let-7f 和 miRNA-31）。miRNA-34a、let-7f 和 miRNA-31 的相对表达水平在早期 EOC 组织和血清样本中明显降低（p<0.0001）。miRNA-34a、let-7f 和 miR-31 的接收者操作特征分析显示，曲线下面积（AUC）分别为 92.0（p<0.0001）、87.9（p<0.0001）和 85.6（p<0.0001），在 III-IV 期和 I-II 期 EOC 血清样本中 AUC 分别为 82.7（p<0.0001）、82.0（p<0.0001）和 81.0（p<0.0001），诊断价值有所提高。miRNA 谱（miRNA-34a+let-7f+miRNA-31）在晚期和早期血清样本中的综合诊断性能分别为 95.5%和 96.9%。
我们的数据将 miRNA 的异常下调与 EOC 中的高甲基化相关联。此外，来自血清的联合 miRNA 谱可以通过更高的 AUC、灵敏度和特异性来预测 EOC 的风险。
