title: Enumeration and targeted analysis of KRAS, BRAF and PIK3CA mutations in CTCs captured by a label-free platform: Comparison to ctDNA and tissue in metastatic colorectal cancer.
abstract: Treatment of advanced colorectal cancer (CRC) requires multimodal therapeutic approaches and need for monitoring tumor plasticity. Liquid biopsy biomarkers, including CTCs and ctDNA, hold promise for evaluating treatment response in real-time and guiding therapeutic modifications. From 15 patients with advanced CRC undergoing liver metastasectomy with curative intent, we collected 41 blood samples at different time points before and after surgery for CTC isolation and quantification using label-free Vortex technology. For mutational profiling, KRAS, BRAF, and PIK3CA hotspot mutations were analyzed in CTCs and ctDNA from 23 samples, nine matched liver metastases and three primary tumor samples. Mutational patterns were compared. 80% of patient blood samples were positive for CTCs, using a healthy baseline value as threshold (0.4 CTCs/mL), and 81.4% of captured cells were EpCAM+ CTCs. At least one mutation was detected in 78% of our blood samples. Among 23 matched CTC and ctDNA samples, we found a concordance of 78.2% for KRAS, 73.9% for BRAF and 91.3% for PIK3CA mutations. In several cases, CTCs exhibited a mutation that was not detected in ctDNA, and vice versa. Complementary assessment of both CTCs and ctDNA appears advantageous to assess dynamic tumor profiles.
authors.affiliation: Department of Medicine, Division of Hepatology and Gastroenterology, Charité University Hospital, Berlin, Germany.|Department of Surgery, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: Evelyn
authors.initials: E
authors.lastname: Kidess-Sigal
authors.affiliation: Vortex BioSciences, Inc., Menlo Park, CA, USA.
authors.forename: Haiyan E
authors.initials: HE
authors.lastname: Liu
authors.affiliation: Department of Surgery, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: Melanie M
authors.initials: MM
authors.lastname: Triboulet
authors.affiliation: Vortex BioSciences, Inc., Menlo Park, CA, USA.
authors.forename: James
authors.initials: J
authors.lastname: Che
authors.affiliation: Department of Surgery, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: Vishnu C
authors.initials: VC
authors.lastname: Ramani
authors.affiliation: Department of Surgery, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: Brendan C
authors.initials: BC
authors.lastname: Visser
authors.affiliation: Department of Surgery, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: George A
authors.initials: GA
authors.lastname: Poultsides
authors.affiliation: Department of Pathology, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: Teri A
authors.initials: TA
authors.lastname: Longacre
authors.affiliation: Boreal Genomics, Vancouver, BC, Canada.
authors.forename: Andre
authors.initials: A
authors.lastname: Marziali
authors.affiliation: Counsyl Inc., San Francisco, CA, USA.
authors.forename: Valentina
authors.initials: V
authors.lastname: Vysotskaia
authors.affiliation: Boreal Genomics, Vancouver, BC, Canada.
authors.forename: Matthew
authors.initials: M
authors.lastname: Wiggin
authors.affiliation: Department of Surgery, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: Kyra
authors.initials: K
authors.lastname: Heirich
authors.affiliation: Department of Surgery, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: Violet
authors.initials: V
authors.lastname: Hanft
authors.affiliation: Comprehensive Cancer Center Charité, Berlin, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Keilholz
authors.affiliation: Department of Radiooncology and Radiotherapy, Charité University Hospital, Berlin, Germany.
authors.forename: Ingeborg
authors.initials: I
authors.lastname: Tinhofer
authors.affiliation: Department of Surgery, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Norton
authors.affiliation: GRAIL, Redwood City, CA, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Lee
authors.affiliation: Vortex BioSciences, Inc., Menlo Park, CA, USA.
authors.forename: Elodie
authors.initials: E
authors.lastname: Sollier-Christen
authors.affiliation: Department of Surgery, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: Stefanie S
authors.initials: SS
authors.lastname: Jeffrey
mesh_terms: D014408:Biomarkers, Tumor / Q000097:blood / Q000235:genetics*; D000074141:Circulating Tumor DNA / Q000097:blood / Q000235:genetics*; D058534:Class I Phosphatidylinositol 3-Kinases / Q000097:blood / Q000235:genetics*; D015179:Colorectal Neoplasms / Q000097:blood / Q000201:enzymology / Q000235:genetics* / Q000473:pathology; D004252:DNA Mutational Analysis / Q000295:instrumentation / Q000379:methods*; D020022:Genetic Predisposition to Disease; D045325:HCT116 Cells; D006801:Humans; D056656:Lab-On-A-Chip Devices; D046210:Microfluidic Analytical Techniques; D009154:Mutation; D009360:Neoplastic Cells, Circulating / Q000378:metabolism* / Q000473:pathology; D010641:Phenotype; D011237:Predictive Value of Tests; D011379:Prognosis; D048493:Proto-Oncogene Proteins B-raf / Q000097:blood / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras) / Q000097:blood / Q000235:genetics*; D015203:Reproducibility of Results; D013997:Time Factors
chemical_list: D014408:Biomarkers, Tumor; D000074141:Circulating Tumor DNA; C117307:KRAS protein, human; D058534:Class I Phosphatidylinositol 3-Kinases; C484760:PIK3CA protein, human; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf; D016283:Proto-Oncogene Proteins p21(ras)
keywords: Vortex; circulating tumor DNA; circulating tumor cells; colorectal cancer; liquid biopsy