Scientists can use liquid biopsy samples to detect and characterize various cancer-derived biomarkers present in the blood. These biomarkers are absent in healthy individuals and those who are cancer-free. Illumina offers innovative next-generation sequencing (NGS) liquid biopsy solutions for cancer biomarker research to analyze:
Several challenges limit the utility of tissue biopsy for use in translational and clinical cancer research, including:
CTCs are cells shed from tumors into the bloodstream. Multiple studies have demonstrated that CTCs have metastatic potential and are associated with aggressive or advanced disease and poor prognosis in various cancer types. While CTCs can serve as biomarkers for liquid biopsy-based cancer characterization, their rarity in the bloodstream (< 1 to < 50 CTCs in 7.5ml of blood on average) remains a significant challenge for detection and characterization. NGS-based technologies, which can detect low levels of CTCs with high throughput capabilities, are opening an exciting frontier for cancer screening and early detection.
Technological advances in single-cell isolation and single-cell sequencing methodologies have enabled detailed analysis of single CTCs at the genomic, transcriptomic, and epigenomic levels. Combining liquid biopsy with single-cell sequencing of CTCs can elucidate the cellular heterogeneity that contributes to tumor biology.
Abnormal methylation patterns are a hallmark of many cancers. Changes in DNA methylation occur early during tumorigenesis and result in a state where most of the genome becomes hypomethylated and CpG islands become hypermethylated.
This switch in global methylation patterns leads to genomic instability and silencing of tumor suppressor genes, driving tumor progression and metastasis. Importantly, multiple studies have demonstrated that the methylation pattern of ctDNA recapitulates the pattern present in the cell/tissue of origin. This indicates that liquid biopsy analysis of ctDNA methylation can be used for early detection of cancer, analysis of tissue of origin, surveillance of minimal residual disease (MRD), monitoring therapy response, and more.
cfRNAs can be released from multiple cell types present in the bloodstream as well as from cancer cells. These ctRNAs are potential biomarkers that can be assayed by liquid biopsy to identify specific cancers, detect cancer initiation, reveal tissue-of-origin, elucidate molecular mechanisms of disease, monitor therapeutic response, and more.
Unlike DNA, which is identical in every cell/tissue (except for genetic variants), RNA is dynamically and differentially expressed between cell types and tissues. This enables ctRNAs to be used to detect cancer and potentially localize it in the body. The diverse nature of RNA expression may also enable use of ctRNAs to determine and classify cancer subtypes early in disease, which is important given the wide range in progression, treatment options, and prognosis between cancers, even those associated with the same organ or tissue.
In this on-demand Illumina webinar, speakers discuss methodologies for sequencing long or short RNAs from liquid biopsy samples, along with implications for cancer research.
This 20+ page eBook provides published, comprehensive workflows for thorough characterization of liquid biopsy samples using NGS and microarrays.
As a genomics technology leader, Illumina offers integrated workflows and innovative solutions that are validated for liquid biopsy analyte sequencing for cancer research.
Sequencing focus | Library prep | Sequencing | Data analysis and visualization |
---|---|---|---|
Single-cell sequencing of CTCs | Multiple commercial offerings for genome, transcriptome, and epigenome | NovaSeq X System NovaSeq 6000 System NextSeq 1000 or NextSeq 2000 Systems |
DRAGEN Single-Cell RNA pipeline |
cfDNA and ctDNA | TruSight Oncology 500 ctDNA v2 Illumina cell-free DNA Prep with Enrichment |
NovaSeq 6000 System | DRAGEN TruSight Oncology 500 ctDNA Analysis Software |
Methylation patterns in cfDNA | Infinium MethylationEPIC BeadChip Kit | iScan System NextSeq 550 System |
GenomeStudio Bioconductor Software |
cfRNA and ctRNA | Illumina RNA Prep with Enrichment | NovaSeq X System NovaSeq 6000 System NextSeq 1000 or NextSeq 2000 Systems |
DRAGEN RNA Pipeline |