Department of Medicine, Liver Cancer Program, Tisch Cancer Institute, Graduate School of Biomedical Sciences, Division of Liver Diseases, Icahn School of Medicine at Mount Sinai, New York, USA.
Department of Visceral Surgery, Lausanne University Hospital CHUV, Lausanne, Switzerland.
Oncogene. 2018 Jul;37(27):3740-3752. doi: 10.1038/s41388-018-0206-3. Epub 2018 Apr 9.
Cellular components of solid tumors including DNA are released into the bloodstream, but data on circulating-free DNA (cfDNA) in hepatocellular carcinoma (HCC) are still scarce. This study aimed at analyzing mutations in cfDNA and their correlation with tissue mutations in patients with HCC. We included 8 HCC patients treated with surgical resection for whom we collected paired tissue and plasma/serum samples. We analyzed 45 specimens, including multiregional tumor tissue sampling (n = 24), peripheral blood mononuclear cells (PMBC, n = 8), plasma (n = 8) and serum (n = 5). Ultra-deep sequencing (5500× coverage) of all exons was performed in a targeted panel of 58 genes, including frequent HCC driver genes and druggable mutations. Mutations detected in plasma included known HCC oncogenes and tumor suppressors (e.g., TERT promoter, TP53, and NTRK3) as well as a candidate druggable mutation (JAK1). This approach increased the detection rates previously reported for mutations in plasma of HCC patients. A thorough characterization of cis mutations found in plasma confirmed their tumoral origin, which provides definitive evidence of the release of HCC-derived DNA fragments into the bloodstream. This study demonstrates that ultra-deep sequencing of cfDNA is feasible and can confidently detect somatic mutations found in tissue; these data reinforce the role of plasma DNA as a promising minimally invasive tool to interrogate HCC genetics.
实体瘤的细胞成分包括 DNA 会释放到血液中，但关于肝细胞癌 (HCC) 中循环游离 DNA (cfDNA) 的数据仍然很少。本研究旨在分析 cfDNA 中的突变及其与 HCC 患者组织突变的相关性。我们纳入了 8 名接受手术切除治疗的 HCC 患者，收集了配对的组织和血浆/血清样本。我们分析了 45 个标本，包括多区域肿瘤组织采样 (n=24)、外周血单核细胞 (PMBC，n=8)、血浆 (n=8) 和血清 (n=5)。在一个 58 个基因的靶向panel 中进行了所有外显子的超深度测序 (5500×覆盖)，其中包括常见的 HCC 驱动基因和可靶向的突变。在血浆中检测到的突变包括已知的 HCC 致癌基因和肿瘤抑制基因 (如 TERT 启动子、TP53 和 NTRK3) 以及一个候选可靶向的突变 (JAK1)。这种方法提高了之前报道的 HCC 患者血浆中突变的检测率。对血浆中 cis 突变的彻底特征分析证实了它们的肿瘤起源，这为 HCC 来源的 DNA 片段释放到血液中提供了明确的证据。本研究表明，cfDNA 的超深度测序是可行的，可以自信地检测到组织中发现的体细胞突变；这些数据强化了血浆 DNA 作为一种有前途的微创工具来检测 HCC 遗传学的作用。
