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番号	年度	題名	雑誌	リンクを見る
17	2024	Analytical and Clinical Validation of a Highly Sensitive NGS-Based ctDNA Assay with Real-World Concordance in NSCLC ABSTRACT PurposeThere have been needs to improve the sensitivity of liquid biopsy. This report aims to report the analytical and clinical validation of a next generation sequencing (NGS)-based circulating tumor DNA (ctDNA) assay.Materials and MethodsAnalytical validation was conducted in vitro by evaluating the limit of detection (LOD), precision, and specificity for various genomic aberrations. The real-world performance in non-small cell lung cancer (NSCLC) was assessed by comparing the results of AlphaLiquid®100 to the tissue-based results.ResultsThe LODs with 30 ng input DNA were 0.11%, 0.11%, 0.06%, 0.21%, and 2.13 copies for detecting SNVs, insertions, deletions, fusions, and copy number alterations (CNA), respectively. Quantitatively, SNV/INDELs, fusions, and CNAs showed a good correlation (R2=0.91, 0.40, and 0.65; y=0.95, 1.06, and 1.19) to the manufacturer’s values, and per-base specificities for all types of variants were near 100%. In real-world NSCLC (n=122), key actionable mutations in NSCLC were detected in 60.7% (74/122) with the ctDNA assay. Comparative analysis against the NGS-based tissue results for all key mutations showed positive percent agreement (PPA) of 85.3%. For individual genes, the PPA was as high as 95.7% for EGFR mutations and 83.3% for ALK translocations. AlphaLiquid 100 detected drug-sensitive EGFR mutation at a variant allele frequency as low as 0.02% and also identified an EGFR mutation in a case where tissue sample missed. Blood samples collected post-targeted therapies revealed additional acquired mutations.ConclusionThe AlphaLiquid®100 ctDNA assay demonstrates robust analytical validity, offering clinically important information for NSCLC patients. Analytical and Clinical Validation of a Highly Sensitive NGS-Based ctDNA Assay with Real-World Concordance in NSCLC リンクを見る	Cancer Research and Treatment	リンクを見る
16	2023	Cancer signature ensemble integrating cfDNA methylation, copy number, and fragmentation facilitates multi-cancer early detection Abstract Cell-free DNA (cfDNA) sequencing has demonstrated great potential for early cancer detection. However, most large-scale studies have focused only on either targeted methylation sites or whole-genome sequencing, limiting comprehensive analysis that integrates both epigenetic and genetic signatures. In this study, we present a platform that enables simultaneous analysis of whole-genome methylation, copy number, and fragmentomic patterns of cfDNA in a single assay. Using a total of 950 plasma (361 healthy and 589 cancer) and 240 tissue samples, we demonstrate that a multifeature cancer signature ensemble (CSE) classifier integrating all features outperforms single-feature classifiers. At 95.2% specificity, the cancer detection sensitivity with methylation, copy number, and fragmentomic models was 77.2%, 61.4%, and 60.5%, respectively, but sensitivity was significantly increased to 88.9% with the CSE classifier (p value < 0.0001). For tissue of origin, the CSE classifier enhanced the accuracy beyond the methylation classifier, fr\|om 74.3% to 76.4%. Overall, this work proves the utility of a signature ensemble integrating epigenetic and genetic information for accurate cancer detection. Cancer signature ensemble integrating cfDNA methylation, copy number, and fragmentation facilitates multi-cancer early detection リンクを見る	Experimental & Molecular Medicine	リンクを見る
15	2023	Personalised circulating tumour DNA assay with large-scale mutation coverage for sensitive minimal residual disease detection in colorectal cancer Abstract Background Postoperative minimal residual disease (MRD) detection using circulating-tumour DNA (ctDNA) requires a highly sensitive analysis platform. We have developed a tumour-informed, hybrid-capture ctDNA sequencing MRD assay. Methods Personalised target-capture panels for ctDNA detection were designed using individual variants identified in tumour whole-exome sequencing of each patient. MRD status was determined using ultra-high-depth sequencing data of plasma cell-free DNA. The MRD positivity and its association with clinical outcome were analysed in Stage II or III colorectal cancer (CRC). Results In 98 CRC patients, personalised panels for ctDNA sequencing were built fr\|om tumour data, including a median of 185 variants per patient. In silico simulation showed that increasing the number of target variants increases MRD detection sensitivity in low fractions (<0.01%). At postoperative 3-week, 21.4% of patients were positive for MRD by ctDNA. Postoperative positive MRD was strongly associated with poor disease-free survival (DFS) (adjusted hazard ratio 8.40, 95% confidence interval 3.49–20.2). Patients with a negative conversion of MRD after adjuvant therapy showed significantly better DFS (P < 0.001). Conclusion Tumour-informed, hybrid-capture-based ctDNA assay monitoring a large number of patient-specific mutations is a sensitive strategy for MRD detection to predict recurrence in CRC. Personalised circulating tumour DNA assay with large-scale mutation coverage for sensitive minimal residual disease detection in colorectal cancer リンクを見る	British Journal of Cancer	リンクを見る
14	2023	Accurate Detection of Urothelial Bladder Cancer Using Targeted Deep Sequencing of Urine DNA Abstract Patients with hematuria are commonly given an invasive cystoscopy test to detect bladder cancer (BC). To avoid the risks associated with cystoscopy, several urine-based methods for BC detection have been developed, the most prominent of which is the deep sequencing of urine DNA. However, the current methods for urine-based BC detection have significant levels of false-positive signals. In this study, we report on uAL100, a method to precisely detect BC tumor DNA in the urine without tumor samples. Using urine samples fr\|om 43 patients with BC and 21 healthy donors, uAL100 detected BC with 83.7% sensitivity and 100% specificity. The mutations identified in the urine DNA by uAL100 for BC detection were highly associated with BC tumorigenesis and progression. We suggest that uAL100 has improved accuracy compared to other urine-based methods for early BC detection and can reduce unnecessary cystoscopy tests for patients with hematuria. Accurate Detection of Urothelial Bladder Cancer Using Targeted Deep Sequencing of Urine DNA リンクを見る	Cancers	リンクを見る
13	2023	Circulating Tumor DNA Dynamics and Treatment Outcome of Regorafenib in Metastatic Colorectal Cancer ABSTRACT Purpose Circulating tumor DNA (ctDNA) is emerging as a valuable non-invasive tool to identify tumor heterogeneity and tumor burden. This study investigated ctDNA dynamics in metastatic colorectal cancer patients treated with regorafenib. Materials and Methods In this prospective biomarker study, plasma cell-free DNA (cfDNA) samples obtained at baseline, at the first response evaluation after 2 cycles of treatment, and at the time of progressive disease (PD) were sequenced using a targeted next-generation sequencing platform which included 106 genes. Results A total of 285 blood samples fr\|om 110 patients were analyzed. Higher baseline cfDNA concentration was associated with worse progression-free survival (PFS) and overall survival (OS). After 2 cycles of treatment, variant allele frequency (VAF) in the majority of ctDNA mutations decreased with a mean relative change of -31.6%. Decreases in the VAF of TP53, APC, TCF7L2, and ROS1 after 2 cycles of regorafenib were associated with longer PFS. We used the sum of VAF at each time point as a surrogate for the overall ctDNA burden. A reduction in sum (VAF) of ≥ 50% after 2 cycles was associated with longer PFS (6.1 vs. 2.7 months, p=0.002), OS (11.3 vs. 5.9 months, p=0.001), and higher disease control rate (86.3% vs. 51.1%, p<0.001). VAF of the majority of the ctDNA mutations increased at the time of disease progression, and VAF of BRAF increased markedly. Conclusion Reduction in ctDNA burden as estimated by sum (VAF) could be used to predict treatment outcome of regorafenib. Circulating Tumor DNA Dynamics and Treatment Outcome of Regorafenib in Metastatic Colorectal Cancer リンクを見る	Cancer Research and Treatment	リンクを見る