Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
Department of Clinical Laboratory Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
J Gastroenterol. 2021 May;56(5):456-469. doi: 10.1007/s00535-021-01773-4. Epub 2021 Mar 12.
Liquid biopsies, particularly those involving circulating tumor DNA (ctDNA), are rapidly emerging as a non-invasive alternative to tumor biopsies. However, clinical applications of ctDNA analysis in hepatocellular carcinoma (HCC) have not been fully elucidated.
We measured the amount of plasma-derived cell-free DNA (cfDNA) in HCC patients before (n = 100) and a few days after treatment (n = 87), including radiofrequency ablation, transarterial chemoembolization, and molecular-targeted agents (MTAs), and prospectively analyzed their associations with clinical parameters and prognosis. TERT promoter mutations in cfDNA were analyzed using droplet digital PCR. Furthermore, we performed a comprehensive mutational analysis of post-treatment cfDNA via targeted ultra-deep sequencing (22,000× coverage) in a panel of 275 cancer-related genes in selected patients.
Plasma cfDNA levels increased significantly according to HCC clinical stage, and a high cfDNA level was independently associated with a poor prognosis. TERT promoter mutations were detected in 45% of all cases but were not associated with any clinical characteristics. cfDNA levels increased significantly a few days after treatment, and a greater increase in post-treatment cfDNA levels was associated with a greater therapeutic response to MTAs. The detection rate of TERT mutations increased to 57% using post-treatment cfDNA, suggesting that the ctDNA was enriched. Targeted ultra-deep sequencing using post-treatment cfDNA after administering lenvatinib successfully detected various gene mutations and obtained promising results in lenvatinib-responsive cases.
Post-treatment cfDNA analysis may facilitate the construction of biomarkers for predicting MTA treatment effects.
液体活检，特别是涉及循环肿瘤 DNA（ctDNA）的液体活检，正迅速成为肿瘤活检的一种非侵入性替代方法。然而，ctDNA 分析在肝细胞癌（HCC）中的临床应用尚未完全阐明。
我们测量了 HCC 患者治疗前（n=100）和治疗后几天（n=87）的血浆游离 DNA（cfDNA）量，包括射频消融、经动脉化疗栓塞和分子靶向药物（MTAs），并前瞻性分析了它们与临床参数和预后的关系。使用液滴数字 PCR 分析 cfDNA 中的 TERT 启动子突变。此外，我们在选定的患者中对 275 个癌症相关基因进行了靶向超深度测序（22,000×覆盖），对治疗后 cfDNA 进行了全面的突变分析。
血浆 cfDNA 水平根据 HCC 临床分期显著升高，高 cfDNA 水平与预后不良独立相关。TERT 启动子突变在所有病例中均有 45%的检出率，但与任何临床特征均无相关性。治疗后 cfDNA 水平显著升高，治疗后 cfDNA 水平升高幅度与 MTA 治疗反应更大相关。使用治疗后 cfDNA 检测到 TERT 突变的检出率增加到 57%，提示 ctDNA 得到了富集。使用 lenvatinib 治疗后对 cfDNA 进行靶向超深度测序，成功检测到各种基因突变，并在 lenvatinib 应答病例中获得了有前景的结果。
治疗后 cfDNA 分析可能有助于构建预测 MTA 治疗效果的生物标志物。
