With a shallow sequencing depth, these reports demonstrated the detection of AR amplification as well as other driver alterations including TMPRSS2:ERG fusion, PTEN deletion, and MYC amplification.75,76 Building on these earlier observations, the association between AR aberration in cfDNA and Tetracaine clinical outcome was investigated in multiple studies in mCRPC patients.77,78 It was noted that AR amplification was more common in patients resistant to ARSI.79 Additionally, pre-treatment cfDNA AR amplifications and mutations were associated with poor clinical outcomes, including worse survival, lower rates of PSA response, and shorter time to radiographic/clinical progression.78 In another study, serial cfDNA samples were sequenced from 97 mCRPC patients treated with abiraterone. several new liquid biopsy fields are emerging, including the characterization of heterogeneity, CTC RNA sequencing, the culture and xenografting of CTCs, and the characterization of extracellular vesicles (EVs) and circulating microRNAs. This review describes the clinical utilization of liquid biopsies in the management of PC patients and emerging liquid biopsy technologies with the potential to advance personalized cancer therapy. strong class=”kwd-title” Keywords: prostate cancer, biomarker, circulating tumor cell, circulating tumor DNA Introduction Liquid biopsy refers to the analysis of blood or other body fluids to obtain clinically or biologically relevant information about a solid malignancy, analogous to information obtained from a traditional tumor biopsy.1 Liquid biopsy encompasses a broad spectrum of approaches aimed at characterizing different components of body fluids, including circulating tumor cells (CTCs), cell-free DNA (cfDNA), circulating RNA, microRNAs, and extracellular vesicles (EVs). (Physique 1) Open in a separate window Physique 1 Schematic overview of liquid biopsy analytes and profiling options in prostate cancer. Abbreviations: CTC, circulating tumor cell; EV, extracellular vesicle. There is an increasing interest in the use of liquid biopsies in the management of prostate cancer (PC), Tetracaine which remains the second leading cause of cancer death in men despite the development of many new therapies.2 From a Tetracaine clinical Tetracaine standpoint, liquid biopsies can be prognostic of PC outcome, predictive of response to treatment, or used to monitor disease. From a biological standpoint, a liquid biopsy serves as a surrogate source of tumor tissue that reflects the full molecular profile of the metastatic disease, thus revealing mechanisms of resistance and paving the way to the development of new therapies. In this review, we discuss the recent advances and key technologies (Tables 1 and ?and2)2) in the field of liquid biopsy, focusing on their use as candidate clinical biomarkers in PC. Additionally, significant breakthrough discoveries and studies are summarized (Physique 2), as well as more recent emerging liquid biopsy fields and their potential impact on PC management. Table 1 CTC capture methods thead th rowspan=”1″ colspan=”1″ Technology /th th rowspan=”1″ colspan=”1″ Method /th th rowspan=”1″ colspan=”1″ Notes /th /thead EpCAM/affinity-based CTC captureCellSearch14EpCAM immunomagnetic bead isolation followed by immunohistochemical staining and semi-automated enumerationFDA cleared; the most clinically validated assayHerringbone chip14Microvortices to increase interactions of CTC and anti-EpCAM coated surfaceHigh sensitivity; can only enrich CTCs for analysis, no single-cell capture capabilityNanoVelcro CTC Chip16Anti-EpCAM coated nanowire and microfluidic chaotic mixerSensitive assay for enumeration; high-purity single-cell isolation; less informative about EpCAM-low cellsMagsweeper153EpCAM-based immunomagnetic captureHigh purity; can isolate single CTCs; less informative about EpCAM-low cellsAdnaTest154EpCAM-based immunomagnetic enrichmentStraightforward enrichment for downstream RNA analysis; contaminating WBCs are presentLiquidBiopsyTM Platform (Cynvenio)155Automated multi-target CTC capture (including EpCAM and PSMA)Multi-antibody capture cocktails increase CTC capture; CLIA-certified downstream NGS workflow; simultaneous cfDNA analysisGEDI Chip18Microfluidic device using combined size and PSMA-based affinity selectionIntact, viable unbound CTCs isolated; high detection ratesVERSA156Customizable capture antibodySimultaneous analysis of RNA, DNA, and protein; marker unfavorable cells may not be capturedNon-affinity-based CTC captureCTC-iChip15Microfluidic inertial focusing followed by removal of WBCsAble to enrich CTCs for RNA profilingISET157Filter-based enrichmentStraightforward commercially available kits for capture/analysis; low specificityParylene-C slot microfilter158Filter-based enrichmentEpitope-independent, filtration-based isolation of heterogeneous populations of CTCs for molecular analysis including telomerase activityClearCell FX21Size-based assay using microfluidic inertial focusingRapid enrichment; can work with fixed or unfixed cellsParsortix22Microfluidic size and size and deformability-based enrichmentCan enrich live CTCs; no staining or enumeration integrated in the workflow to the enriched cellsApoStream23Dielectric focusing to isolate cells; immunofluorescence for tumor-specific markersPhysical selection method that avoids physical deformation of cellsNon-enrichment high content CTC analysisEpic24High content scanning using morphometric and immunofluroscence algorithms with whole blood inputNo cell left behind C Rabbit Polyclonal to MED26 all nucleated cells are analyzed; available for send-out assays (commercial AR-V7); validated in large PC cohortsRarecyte Cytefinder25Density-based removal of WBC and plasma, followed by immunofluorescence staining and visual confirmationAll nucleated cells are scanned, and single cells can be retrieved for downstream analysis with integrated robotic micropipette Open in a separate window Abbreviations: EpCAM, Epithelial cell adhesion molecule; CTC, circulating tumor cell; WBC, white blood cell; PSMA, Prostate-Specific Membrane Antigen; CLIA, Clinical Laboratory Improvement Amendments; NGS, next-generation sequencing; PC, prostate cancer. Table 2 cfDNA technologies thead th rowspan=”1″ colspan=”1″ /th th rowspan=”1″ colspan=”1″ Molecular applications /th th rowspan=”1″ colspan=”1″ Quantitation /th th rowspan=”1″ colspan=”1″ Sensitivity Tetracaine of detection /th th rowspan=”1″ colspan=”1″ Example /th /thead PCR assaysAllele-Specific PCRKnown recurring mutationsSemiquantitative 0.01%Cobas (Roche),159 Therascreen (Qiagen)160Emulsion PCRKnown recurring mutationsAbsolute quantitation, able to characterize a wide dynamic range 0.01%Droplet digital PCR,30?BEAMing31NGS assaysAmplicon-Based Targeted NGSHotspot single nucleotide mutations and copy number gainsQuantitation of relative AF 0.1%TAm-seq,161 eTAm-seq162 Oncomine Assays (Thermo Fisher)163Capture-Based Targeted NGSSingle nucleotide mutations, gene fusions, copy number gains within the selected regionQuantitation of comparative AF 0.1%Guardant 360,164 TEC-seq165NontargetedAll variants, including genome-wide rearrangementsQuantitation of relative AF 1%, deeper sequencing is costlyWhole genome sequencing166 or whole exome sequencing167 Open up in.
