Global Hypomethylation Biomarkers for Cervical Cancer Screening in Women Living with HIV in LMICs

项目摘要 宫颈癌是中低收入国家最常见的癌症之一。 这种情况因#年人类免疫缺陷病毒(HIV)感染的高流行率而恶化。 某些非洲国家，如尼日利亚和坦桑尼亚。有效的筛查和早期发现是 预防CC的关键。然而，筛查试验的多次巴氏涂片检查在LMIC和 CC预防战略的覆盖面覆盖了较少的LMIC中有CC风险的妇女，特别是感染了艾滋病毒的妇女 女人。一种简单、负担得起、非侵入性的HIV相关性CC一线筛查工具 是艾滋病毒高流行率的低收入国家迫切需要的。 HIV感染促进宫颈癌发生的分子变化在很大程度上仍不清楚。 表观遗传异常，特别是重复元件(RE)的全球DNA甲基化(DNaM)丢失 地区，已被认为是人类癌症的标志。RES是发生在 基因组中有多个拷贝。如果RES被激活(例如，通过艾滋病毒感染)，它们可以 在新的基因组位置繁殖并重新插入到人类DNA中，导致基因组不稳定 以及可能导致癌症的体细胞突变。DNaM在这些RE中是一种稳定的保护机制 Re是由易位引起的，在肿瘤发生的早期就观察到了它的丢失。 具体地说，艾滋病毒感染被证明降低了全球dNaM水平并重新激活了RE易位 活动。因此，我们假设HIV感染可能通过引起全球 自体宫颈上皮内瘤变中RE去甲基化及其表观遗传学改变 (CIN)样本可预测进展为侵袭性CC。 我们提出了两个研究目标。在目标1中，我们将识别和验证与艾滋病毒相关的全球CC RE dNaM 生物标志物。我们将利用我们正在进行的U54 CC表观基因组学项目中的现有dNaM数据 尼日利亚(U54CA221205，PI：HOU/Murphy)为生物标志物开发生成全球RE dNaM数据 使用我们的新生物信息学方法。然后，我们将通过实现一个 负担得起、有针对性和定量的基于PCR的dNaM平台在LMIC实验室。在目标2中，使用 同样基于聚合酶链式反应的方法，我们将测试在目标1中验证的生物标记物是否可以预测CC的风险 进步。我们将利用两组来自HIV阳性妇女纵向队列的样本 谁患有低度CIN：a)尼日利亚的巴氏涂片样本来自我们的U54队列；b)坦桑尼亚 宫颈阴道拭子样本来自独立的U54队列(U54CA190155，PI：Wood/Soliman)。 在我们坦桑尼亚队列中自我收集的宫颈阴道拭子中测试我们的生物标记物，使我们能够测试 它们在LMIC环境中的可行性和临床相关性。如果成功，我们的研究可能有助于开发新的 未来可能为LMICs中的艾滋病毒携带者妇女提供CC筛查和早期检测工具。

Project Summary Cervicalcancer (CC) is one of the most common cancers in low and middle-income countries (LMICs). This situation is worsened by a high prevalence of human immunodeficiency virus (HIV) infection in certain African countries, such as Nigeria and Tanzania. Effective screening and early detection is the key to preventing CC. However, multiple Pap smear visits for screening test remains costly in LMICs and coverage of CC preventive strategy reach fewer women at risk of CC in LMICs, in particular HIV-infected women. An alternative easy, affordable, non-invasive CC front-line screening tool for HIV-associated CC is urgently needed in LMICs with high HIV prevalence. The molecular changes by which HIV infection promotes cervical carcinogenesis remain largely unknown. Epigenetic aberrations, especially global DNA methylation (DNAm) loss in repetitive element (RE) regions, have been recognized as a hallmark of human cancers. REs are DNA sequences that occur in multiple copies throughout the genome. If REs are activated (for example, by HIV infection) they can multiply and reinsert themselves into human DNA at new genomic locations, leading to genomic instability and somatic mutations that may cause cancer. DNAm in these REs is a protective mechanism to stabilize RE from translocation, and its loss has been observed seen in the early phase of tumorigenesis. Specifically, HIV infection has been shown to reduce global DNAm level and reactivate RE translocation activity. We thus hypothesize that HIV infection may promote CC development via causing global demethylation of RE and that such epigenetic changes in self-collected cervical intraepithelial neoplasia (CIN) samples may predict progression into invasive CC. We propose two study aims. In Aim 1, we will identify and validate HIV-associated CC global RE DNAm biomarkers. We will utilize the existing DNAm data from our ongoing U54 CC epigenomic project in Nigeria (U54CA221205, PI: Hou/Murphy) to generate global RE DNAm data for biomarker development using our novel bioinformatics methods. We will then validate the biomarkers by implementing an affordable, targeted, and quantitative PCR-based DNAm platform in a LMIC laboratory. In Aim 2, using the same PCR-based approach, we will test if the biomarkers validated in Aim 1 can predict risk of CC progression. We will leverage two groups of samples from longitudinal cohorts of HIV-positive women who had low-grade CIN: a) Nigeria Pap smear samples from our U54 cohort; and b) Tanzania cervicovaginal swab samples from an independent U54 cohort (U54CA190155, PI: Wood/Soliman). Testing our biomarkers in self-collectable cervicovaginal swabs in our Tanzania cohort allows us to test their feasibility and clinical relevance in LMIC settings. If successful, our study may help develop new possible future CC screening and early detection tools for women living with HIV in LMICs.