Validation of circulating tumor DNA assays for detection of metastatic melanoma

用于检测转移性黑色素瘤的循环肿瘤 DNA 检测的验证

• 批准号: 9768979
• 负责人: DAVID POLSKY
• 金额: $ 40.57万
• 依托单位: NEW YORK UNIVERSITY SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-07 至 2021-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9768979
• 关键词: Adjuvant; Adjuvant Therapy; BRAF gene; Biological Assay; Biological Markers; Cancer Patient; Cells; Characteristics; Clinic; Clinical; Clinical Data; Clinical Trials; Collaborations; Consensus; DNA; Data; Data Set; Detection; Development; Diagnostic; Diagnostic radiologic examination; Disease; Disease Progression; Excision; Gene Mutation; Genes; Genetic screening method; Goals; Hot Spot; Laboratories; Lactate Dehydrogenase; Lymphatic; MAP Kinase Gene; Malignant Neoplasms; Measures; Metastatic Melanoma; Molecular; Monitor; Mutation; Mutation Detection; Neoplasm Metastasis; Nivolumab; Operative Surgical Procedures; Outcome; Pathologic; Pathway interactions; Patients; Performance; Phase; Pilot Projects; Plasma; Plasma Cells; Procedures; Process; Promoter Regions; Quality Control; RNA-Directed DNA Polymerase; Reagent; Recurrence; Relapse; Reproducibility; Research; Resected; Running; Sampling; Scanning; Sensitivity and Specificity; Serum; Specificity; Specimen; Staging System; Surgical Management; Systemic disease; Technology; Telomerase; Testing; Time; Tumor Burden; United States; Unresectable; Validation; Visceral; base; blood-based biomarker; burden of illness; circulating DNA; design; digital; disorder later incidence prevention; effective therapy; efficacy study; follow-up; immune checkpoint blockade; immune checkpoint blockers; improved; melanoma; mutant; predictive modeling; prospective; public health relevance; reagent standardization; response; routine imaging; serological marker; specific biomarkers; targeted treatment; trial comparing; tumor; tumor DNA

 DESCRIPTION (provided by applicant): Leveraging the high sensitivity, specificity and quantitative capability of the droplet digital PCR (ddPCR) platform, this project seeks to analytically and clinically validate ddPCR assays for 7 melanoma-associated hot- spot mutations for use as blood-based biomarkers of disease recurrence in patients with resected metastatic melanoma. In the United States, the only commonly used serologic marker to monitor disease recurrence in patients with resected metastatic melanoma is serum lactate dehydrogenase (LDH), which suffers from low sensitivity and specificity. With new, effective therapies for systemic disease being applied in the adjuvant setting, a sensitive and specific biomarker that can identify early disease recurrence could prompt clinicians to change patient management while the patient has a low tumor burden. Recently, highly sensitive and specific technologies, such as ddPCR, have revealed that cancer patients have abnormally high levels of cell-free, tumor-associated DNA (ctDNA) circulating in their plasma that generally correlate positively with metastatic tumor burden. We conducted a pilot study utilizing ddPCR to detect changes in mutant BRAF and NRAS ctDNA levels in patients with unresectable stage IV melanoma who were undergoing treatment with BRAF- targeted therapies or immune checkpoint blockade. Importantly for this application, we found that at the time of treatment initiation, ctDNA was a much more sensitive marker of low disease burden than LDH. ctDNA levels were elevated in 71% of patients with RECIST scores < 5cm at the start of systemic treatment compared to LDH, which was only elevated in 8% of patients. While these encouraging results were obtained with assays that detect 1 of the 5 of the most common melanoma-associated BRAF and NRAS mutations, collectively these 5 mutations are present in only 55% - 65% of patients. Recently, 2 functional, hotspot mutations in the promoter region of the telomerase reverse-transcriptase gene (TERT) were identified in many cancers including melanoma. Our preliminary studies have also found these TERT mutations frequently in melanoma and when evaluated with BRAF and NRAS mutations, 86% of patients have 1 or more of the 7 BRAF, NRAS or TERT mutations in their melanomas. In this application, we will analytically validate ddPCR assays for the 7 common mutations in BRAF, NRAS and TERT, and test the hypothesis that a rise in ctDNA levels, as measured by 1 of these 7 ddPCR assays will predict radiographic recurrence in resected metastatic patients prior to routine imaging scans. Development of plasma biomarkers that can accurately detect disease progression with high sensitivity can augment or replace the routine radiographic scans obtained every 3 months with scans ordered in response to a rise in the plasma ctDNA level. Also it could lay the groundwork for a clinical trial comparing the utility of adjuvant therapy for all resected patients versus selecting patients for treatment when evidence of micrometastatic disease emerges based on a rise in ctDNA levels.

 描述（由申请人提供）：利用液滴数字 PCR (ddPCR) 平台的高灵敏度、特异性和定量能力，该项目旨在对 7 种黑色素瘤相关热点突变的 ddPCR 检测进行分析和临床验证，以用作切除的转移性黑色素瘤患者疾病复发的血液生物标志物。在美国，唯一常用的监测转移性黑色素瘤切除患者疾病复发的血清学标志物是血清乳酸脱氢酶（LDH），但其敏感性和特异性较低。随着新的、有效的全身性疾病疗法在辅助治疗中的应用，一种能够识别早期疾病复发的敏感且特异的生物标志物可能会促使临床医生在患者肿瘤负荷较低的情况下改变患者的治疗方法。最近，高度敏感和特异性的技术（例如 ddPCR）显示，癌症患者血浆中循环的无细胞肿瘤相关 DNA (ctDNA) 水平异常高，通常与转移性肿瘤负荷呈正相关。我们进行了一项试点研究，利用 ddPCR 检测正在接受 BRAF 靶向治疗或免疫检查点阻断治疗的不可切除的 IV 期黑色素瘤患者的突变 BRAF 和 NRAS ctDNA 水平的变化。对于该应用来说重要的是，我们发现在治疗开始时，ctDNA 是比 LDH 更敏感的低疾病负担标志物。在全身治疗开始时，RECIST 评分 < 5cm 的患者中有 71% 的 ctDNA 水平升高，而 LDH 的水平仅在 8% 的患者中升高。虽然这些令人鼓舞的结果是通过检测 5 种最常见的黑色素瘤相关 BRAF 和 NRAS 突变中的 1 种的检测获得的，但总的来说，这 5 种突变仅存在于 55% - 65% 的患者中。最近，在包括黑色素瘤在内的许多癌症中，发现了端粒酶逆转录酶基因 (TERT) 启动子区域的 2 个功能性热点突变。我们的初步研究还发现，这些 TERT 突变在黑色素瘤中很常见，当用 BRAF 和 NRAS 突变进行评估时，86% 的患者在黑色素瘤中存在 7 种 BRAF、NRAS 或 TERT 突变中的 1 种或多种。在此应用中，我们将分析验证 BRAF、NRAS 和 TERT 7 种常见突变的 ddPCR 检测，并测试以下假设：通过这 7 种 ddPCR 检测中的 1 种检测测量的 ctDNA 水平升高将在常规成像扫描之前预测已切除的转移性患者的放射学复发。开发能够以高灵敏度准确检测疾病进展的血浆生物标志物，可以通过响应血浆 ctDNA 水平上升而进行的扫描来增强或取代每 3 个月进行的常规放射线扫描。它还可以为比较辅助治疗对所有切除患者的效用的临床试验奠定基础 与根据 ctDNA 水平升高出现微转移性疾病证据时选择患者进行治疗相比。