Table 4 Liquid biopsy technique in GC
From: Clinical application and detection techniques of liquid biopsy in gastric cancer
Testing Target | Testing purpose | Testing Technology | Testing Advantages | Testing Disadvantages | References |
|---|---|---|---|---|---|
CTCs | Isolation and enrichment | Micro-electro-mechanical system (MEMS) | Simple and easy to operate | The large difference in size of different tumor cells, etc., makes it impossible to uniformly | [47] |
Isolation by size of epithelial tumor cells(ISET) | [48] | ||||
Microfluidics | [49] | ||||
Dual-Aptamer-Targeted Immunomagnetic Nanoparticles | Dependence on immunological antibodies for specific capture of CTCs | Recovery of EpCAM + CTCs only | [50] | ||
CellSearch | Semi-automatic and can process multiple samples at once | Enriched CTCs population exerts EpCAM bias | [37] | ||
Testing | qPCR and protein detection techniques (immunofluorescence, immunohistochemistry, fluorescence-assisted in situ hybridization.) | Enables quantitative and accurate testing | Longer detection time and less specificity | ||
Fiber-optic array scanning technology (FAST) | Detect low levels of CTCs without enrichment | Higher cost | [63] | ||
Epithelial immune spots | Detection of proteins secreted/released/shed by individual epithelial cancer cells | Smaller sample size for one-time processing | [64] | ||
Whole genome amplification (WGA) | Rapid and efficient detection of specific proteins or markers of CTCs | Lower specificity and higher cost | [71] | ||
Single-cell sequencing | Ability to detect its properties at the individual cell level | Lower level reflected | [71] | ||
cfDNA/ctDNA | PCR-based detection | qPCR、dPCR、ddPCR、allele-specific PCR, quantitative methylation-specific PCR, BEAMing, ARMS, and COLD-PCR | Quantitative detection of target molecules with improved detection sensitivity and lower cost | The number of mutations detected is limited, the detection area is restricted, and the sample size increases with the number of times the assay is used | |
NGS-based detection | Targeted NGS Technology(TAm-Seq, Safe-SeqS, CAPP-Seq and molecular barcoding or digital error suppression) | Can identify tumor mutations in some patients with high sensitivity | The number of detected tumor mutations is low and contains a large number of positional tumor mutations that are not detected | ||
Non-targeted NGS technology(WGS and WES) | Detects all tumor mutations in patients and can be used for genome-wide copy number analysis and large structural variant detection | Lower sensitivity and higher cost | [121] | ||
ncRNAs | PCR-based detection | RT-qPCR, dPCR, and ddPCR | Better sensitivity, repeatability, and accuracy | The number of molecules detected is limited and the sample size increases with the number of times the assay is used | [174] |
NGS-based detection | Gene chips | Preliminary screening and mapping of ncRNAs can be obtained | Lower specificity and higher cost | [175] | |
RNA-Seq | Preliminary screening and mapping of ncRNAs can be obtained | Lower specificity and higher cost | [175] | ||
Detecting the presence of functional ncRNAs | RNAdetect | Accurate detection of the presence of functional ncRNAs | High dependency | [176] | |
Isothermal amplification technique detection | Catalytic hairpin assembly (CHA) | The detection conditions are relatively simple and allow for amplification of the target molecule, making it easy to detect | Poor specificity | [183] | |
Detection of new technologies | Molecular beacons (MB), DNA tetrahedron probe, Localized surface plasmon resonance (LSPR), Thermophoresis-assisted detection and CRISPR/CAS system-assisted detection | Easy and convenient operation, lower detection limit | Poor specificity or low sensitivity | ||
Exosome | Isolation and enrichment | Differential Ultracentrifugation (DUC) and Density Gradient Ultracentrifugation (DG-UC) | Exosome isolation and enrichment based on particle size and solution viscosity, simple operation and high extraction purity | Lower recovery efficiency and purity | [201] |
Ultrafiltration | Simple operation, high purification | Lower yield | [202] | ||
Sedimentation Technology | Highly hydrophilic polymers can be used to competitively bind to water molecules around the exosome membrane, thereby reducing solubility and enabling exosome separation | Lack of specificity, serious contamination, difficult to expand | [203] | ||
Immunoaffinity enrichment method | High specificity, better differentiation between exosomes of cancer cell origin and exosomes of normal cell origin | Higher cost and high dependency | [205] | ||
Microbeads, microfluidic chips, and thermal enrichment | Improved efficiency and detection limits of exosome enrichment | Higher cost and high dependency | |||
Lipid‑based separation | Reduce the damage of exosome and extract effectively | With other pollution and lack of specificity | [206] | ||
Testing | Traditional Western Blot (WB) or enzyme-linked immunosorbent assay (ELISA) | Specifically detects exosomal membrane proteins or other marker proteins | Complex steps and low sensitivity | [210] | |
Scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), and dynamic light scattering (DLS) | Easy, fast, and visual operation | Samples are susceptible to damage from external conditions and are more expensive | [211] | ||
Nanoparticle Tracking Analysis (NTA) | Visualize and provide numerous information on exosomes | Complex operation and poor repeatability | [160] | ||
Colorimetric method | Easy to operate and visualize | High dependent and subject to external interference | [215] | ||
Fluorescence detection | Low cost, non-destructive, multiplex detection capability, easy automation | High dependent and subject to external interference | [213] | ||
Surface Plasmon Resonance (SPR) | No sample preparation and a label-free, real-time molecular sensing technique | High dependent | [214] | ||
Surface enhanced Raman scattering (SERC) | Enabled cheap, portable, and easily available establishment of detection | Higher cost and high dependency | [217] | ||
Electrochemical testing | High sensitivity, high selectivity, low cost, easy to use | High dependent | [212] | ||
CRISPR/CAS system-assisted detection | High specificity | Complex operation and low sensitivity | |||
Single exosome detection | Provide more accurate tumor progression information and reflect individual differences, and have strong specificity | Low detection rate and high personalization cost | [218] |