Kumar Vivek, Gupta Sameer, Chaurasia Amrita, Sachan Manisha
Department of Biotechnology, Motilal Nehru National Institute of Technology, Allahabad, India.
Department of Surgical Oncology, King George Medical University, Lucknow, India.
Front Oncol. 2021 Oct 7;11:681872. doi: 10.3389/fonc.2021.681872. eCollection 2021.
Epithelial ovarian cancer (EOC) is one of the most lethal gynecological malignancies among women worldwide. Early diagnosis of EOC could help in ovarian cancer management. MicroRNAs, a class of small non-coding RNA molecules, are known to be involved in post-transcriptional regulation of ~60% of human genes. Aberrantly expressed miRNAs associated with disease progression are confined in lipid or lipoprotein and secreted as extracellular miRNA in body fluid such as plasma, serum, and urine. MiRNAs are stably present in the circulation and recently have gained an importance to serve as a minimally invasive biomarker for early detection of epithelial ovarian cancer.
Genome-wide methylation pattern of six EOC and two normal ovarian tissue samples revealed differential methylation regions of miRNA gene promoter through MeDIP-NGS sequencing. Based on log2FC and -value, three hypomethylated miRNAs (miR-205, miR-200c, and miR-141) known to have a potential role in ovarian cancer progression were selected for expression analysis through qRT-PCR. The expression of selected miRNAs was analyzed in 115 tissue (85 EOC, 30 normal) and 65 matched serum (51 EOC and 14 normal) samples.
All three miRNAs (miR-205, miR-200c, and miR-141) showed significantly higher expression in both tissue and serum cohorts when compared with normal controls ( < 0.0001). The receiver operating characteristic curve analysis of miR-205, miR-200c, and miR-141 has area under the curve (AUC) values of 87.6 ( < 0.0001), 78.2 ( < 0.0001), and 86.0 ( < 0.0001), respectively; in advance-stage serum samples, however, ROC has AUC values of 88.1 ( < 0.0001), 78.9 ( < 0.0001), and 86.7 ( < 0.0001), respectively, in early-stage serum samples. The combined diagnostic potential of the three miRNAs in advance-stage serum samples and early-stage serum samples has AUC values of 95.9 (95% CI: 0.925-1.012; sensitivity = 96.6% and specificity = 80.0%) and 98.1 (95% CI: 0.941-1.021; sensitivity = 90.5% and specificity = 100%), respectively.
Our data correlate the epigenetic deregulation of the miRNA genes with their expression. In addition, the miRNA panel (miR-205 + miR-200c + miR-141) has a much higher AUC, sensitivity, and specificity to predict EOC at an early stage in both tissue and serum samples.
上皮性卵巢癌（EOC）是全球女性中最致命的妇科恶性肿瘤之一。EOC的早期诊断有助于卵巢癌的治疗。微小RNA（miRNA）是一类小的非编码RNA分子，已知参与约60%人类基因的转录后调控。与疾病进展相关的异常表达的miRNA局限于脂质或脂蛋白中，并作为细胞外miRNA分泌到血浆、血清和尿液等体液中。miRNA稳定存在于循环中，最近已成为早期检测上皮性卵巢癌的微创生物标志物。
通过甲基化DNA免疫沉淀测序（MeDIP-NGS）对6个EOC组织样本和2个正常卵巢组织样本进行全基因组甲基化模式分析，揭示miRNA基因启动子的差异甲基化区域。基于log2倍变化值（log2FC）和P值，选择3个已知在卵巢癌进展中具有潜在作用的低甲基化miRNA（miR-205、miR-200c和miR-141），通过实时定量逆转录聚合酶链反应（qRT-PCR）进行表达分析。在115个组织样本（85个EOC样本和30个正常样本）和65个匹配的血清样本（51个EOC样本和14个正常样本）中分析所选miRNA的表达。
与正常对照相比，所有3个miRNA（miR-205、miR-200c和miR-141）在组织和血清样本中均表现出显著更高的表达（P<0.0001）。miR-205、miR-200c和miR-141的受试者工作特征曲线分析的曲线下面积（AUC）值分别为87.6（P<0.0001）、78.2（P<0.0001）和86.0（P<0.0001）；然而，在晚期血清样本中，早期血清样本的ROC曲线下面积值分别为88.1（P<0.0001）、78.9（P<0.0001）和86.7（P<0.0001）。这3个miRNA在晚期血清样本和早期血清样本中的联合诊断潜力的AUC值分别为95.9（95%置信区间：0.925-~1.012；灵敏度=96.6%，特异性=80.0%）和98.1（95%置信区间：0.941-1.021；灵敏度=90.5%，特异性=100%）。
我们的数据将miRNA基因的表观遗传失调与其表达相关联。此外，miRNA组合（miR-205+miR-200c+miR-141）在组织和血清样本中预测早期EOC具有更高的AUC、灵敏度和特异性。
