1Cancer Center Amsterdam, Department of Pathology, VU University Medical Center, Amsterdam, The Netherlands.
2Department of Epidemiology and Biostatistics, VU University Medical Center, Amsterdam, The Netherlands.
Clin Epigenetics. 2018 Jun 7;10:76. doi: 10.1186/s13148-018-0509-9. eCollection 2018.
Primary testing for high-risk HPV (hrHPV) is increasingly implemented in cervical cancer screening programs. Many hrHPV-positive women, however, harbor clinically irrelevant infections, demanding additional disease markers to prevent over-referral and over-treatment. Most promising biomarkers reflect molecular events relevant to the disease process that can be measured objectively in small amounts of clinical material, such as miRNAs. We previously identified eight miRNAs with altered expression in cervical precancer and cancer due to either methylation-mediated silencing or chromosomal alterations. In this study, we evaluated the clinical value of these eight miRNAs on cervical scrapes to triage hrHPV-positive women in cervical screening.
Expression levels of the eight candidate miRNAs in cervical tissue samples ( = 58) and hrHPV-positive cervical scrapes from a screening population ( = 187) and cancer patients ( = 38) were verified by quantitative RT-PCR. In tissue samples, all miRNAs were significantly differentially expressed ( < 0.05) between normal, high-grade precancerous lesions (CIN3), and/or cancer. Expression patterns detected in cervical tissue samples were reflected in cervical scrapes, with five miRNAs showing significantly differential expression between controls and women with CIN3 and cancer. Using logistic regression analysis, a miRNA classifier was built for optimal detection of CIN3 in hrHPV-positive cervical scrapes from the screening population and its performance was evaluated using leave-one-out cross-validation. This miRNA classifier consisted of miR-15b-5p and miR-375 and detected a major subset of CIN3 as well as all carcinomas at a specificity of 70%. The CIN3 detection rate was further improved by combining the two miRNAs with HPV16/18 genotyping. Interestingly, both miRNAs affected the viability of cervical cancer cells in vitro.
This study shows that miRNA expression analysis in cervical scrapes is feasible and enables the early detection of cervical cancer, thus underlining the potential of miRNA expression analysis for triage of hrHPV-positive women in cervical cancer screening.
高危型人乳头瘤病毒（hrHPV）的初次检测在宫颈癌筛查项目中得到了越来越多的应用。然而，许多 hrHPV 阳性的女性携带临床上无意义的感染，需要额外的疾病标志物来避免过度转诊和过度治疗。最有前途的生物标志物反映了与疾病过程相关的分子事件，可以在少量临床标本中客观地测量，如 microRNA。我们之前发现了 8 种在宫颈癌前病变和癌症中由于甲基化介导的沉默或染色体改变而表达改变的 microRNA。在这项研究中，我们评估了这 8 种 microRNA 在宫颈刮片中的临床价值，以对宫颈癌筛查中 hrHPV 阳性的女性进行分类。
通过定量 RT-PCR 验证了 8 个候选 microRNA 在宫颈组织样本（n=58）和宫颈癌筛查人群的 hrHPV 阳性宫颈刮片中（n=187）以及癌症患者（n=38）的表达水平。在组织样本中，所有 microRNA 在正常、高级别癌前病变（CIN3）和/或癌症之间的表达均有显著差异（<0.05）。在宫颈刮片中检测到的表达模式与组织样本相似，其中 5 个 microRNA 在对照组和 CIN3 及癌症患者之间的表达有显著差异。使用逻辑回归分析，建立了一个用于最优检测宫颈癌筛查人群中 hrHPV 阳性宫颈刮片中 CIN3 的 microRNA 分类器，并通过留一法交叉验证评估其性能。该 microRNA 分类器由 miR-15b-5p 和 miR-375 组成，在特异性为 70%的情况下可以检测到大部分 CIN3 以及所有的癌。通过将这两个 microRNA 与 HPV16/18 基因分型相结合，可以进一步提高 CIN3 的检测率。有趣的是，这两个 microRNA 都能影响体外宫颈癌细胞的活力。
本研究表明，宫颈刮片中的 microRNA 表达分析是可行的，能够早期检测宫颈癌，从而强调了 microRNA 表达分析在宫颈癌筛查中对 hrHPV 阳性女性进行分类的潜力。
