血中循環腫瘍DNAの解析
無細胞血中循環腫瘍DNA（ctDNA）は、侵襲的な組織生検に代わる手法として、非侵襲的がんバイオマーカーとなる可能性があります。現在、さまざまな種類のがんを検出するバイオマーカーとしてctDNAを使用する手法が研究されています1。今後、治療反応性のリアルタイムモニタリングや治療候補同定の非侵襲的手法としてctDNAが台頭する可能性があります。2
次世代シーケンス（NGS）は、血中のわずかなctDNAの検出に必要な精度と特異性を提供します。NGSでは、単一遺伝子または一部の遺伝子をターゲットとするだけでなく、ctDNAにおける腫瘍由来の変異をゲノムワイドに同定することもできます。
体細胞変異検出に利用されるctDNA
これまで、がんバイオマーカーとして血清タンパク質が使用されてきましたが、この手法ではドライバー変異や腫瘍の不均一性に関する情報が得られないため、有用性には限界があります1。これに比べ、腫瘍DNAにおける体細胞変異は、特異的かつ精確なバイオマーカーとなります。NGSが登場し、がんに伴うゲノム変化に関する知見が蓄積されることで、低頻度の体細胞変異を高精度で精確に同定できる可能性が高まっています。
The Value of ctDNA and RNA Analysis
According to Professor Jo Vandesompele, PhD, liquid biopsy testing based on DNA analysis is growing rapidly for cancer applications. He also sees significant growth opportunities for RNA analysis in the liquid biopsy space and outside of the field of oncology. He discusses ongoing research aimed at deciphering the role of long non-coding RNA in cancer.
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The Potential of Monitoring ctDNA with NGS
In the future, circulating tumor DNA sequencing might play a role in cancer diagnosis, prognosis, and measuring treatment response.
The Future Potential of ctDNA and Liquid Biopsies in Cancer
Companion Diagnostics
- Identify actionable alterations in tumors without an invasive biopsy
- Measure tumor heterogeneity
Monitoring for Therapeutic Response
- Determine treatment efficacy
- Test for new actionable alterations
Monitoring for Residual Disease
- Assess remission or progression
Screening
- Determine presence of disease with no prior evidence
ctDNA Sequencing Research Articles
Analyzing Exosomal DNA from Pancreatic Cancer Samples
NGS analysis of exosomal DNA found in the blood of pancreatic cancer subjects gives researchers insight into the potential of liquid biopsies.
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Searching for Cancer Driver Gene Expression Clues in ctDNA
Whole-genome sequencing of ctDNA samples enables researchers to analyze nucleosome patterns and infer the gene expression status of cancer driver genes.
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The Power and Promise of Liquid Biopsies
Dr. Phil Febbo, Chief Medical Officer at Illumina, discusses the future potential of liquid biopsies and circulating tumor DNA analysis.
Read ArticleFeatured ctDNA Research Products
TruSight Oncology 500 ctDNA
Assay targeting multiple somatic variant types from plasma, including tumor mutational burden and microsatellite instability.
View ProductTruSight Oncology UMI Reagents
These unique molecular identifiers reduce background noise in sequencing data, enabling detection of low-frequency variants.
View ProductNovaSeq 6000 System
Combines scalable throughput, speed, and flexibility for virtually any sequencing method, genome, and scale of project.
View SystemRelated Content
Cancer RNA Sequencing
This method provides functional information about cancer gene expression and the gene fusions that drive tumor progression.
Somatic Mutation Analysis
NGS offers high sensitivity, ease of use, and accurate data quality for identifying even rare mutations successfully.
Pan-Cancer Analysis
Expert-defined pan-cancer NGS panels can comprehensively assesses gene variants and abnormalities associated with many common cancers, regardless of tumor origin.
がんバイオマーカーモニタリングの可能性
今後はctDNAが、がんの診断、予後、および治療反応性の評価に利用される可能性があります。
がんにおけるDNAバイオマーカーの未来
コンパニオン診断
- 生検を実施することなく、腫瘍におけるアクショナブルな変異を同定
- 腫瘍の不均一性を評価
治療反応性を評価
- 治療の有効性を判断
- 新しいアクショナブルな変異を検査
残留疾患をモニタリング
- 寛解または進行を評価
スクリーニング
- エビデンスの得られていない疾患の有無を診断
追加のリソース
An Ultrasensitive Method for Quantitating ctDNA
Newman et al. introduce cancer personalized profiling by deep sequencing (CAPP-Seq) for quantifying ctDNA.
Analysis of ctDNA as a Metastatic Breast Cancer Biomarker
Dawson et al. use ctDNA to monitor metastatic breast cancer.
RNA Biomarkers for Drug Response
Find resources designed to help you adopt RNA-Seq for drug response RNA biomarker discovery and profiling.
References
- Bettegowda C, Sausen M, Leary RJ, et al. Detection of circulating tumor DNA in early- and late-stage human malignancies. Sci Transl Med. 2014;6:224ra24.
- DeMartin T (2014) Gene Trek: Clinical Impacts of Next Generation Sequencing. AG Scientific (info.agscientific.com/blog/bid/203182/Gene-Trek-Clinical-Impacts-of-Next-Generation-Sequencing)