title: Comparison of cell stabilizing blood collection tubes for circulating plasma tumor DNA.
abstract: OBJECTIVE
  Circulating plasma DNA is being increasingly used for biomedical and clinical research as a substrate for genetic testing. However, cell lysis can occur hours after venipuncture when using standard tubes for blood collection, leading to an increase in contaminating cellular DNA that may hinder analysis of circulating plasma DNA. Cell stabilization agents can prevent cellular lysis for several days, reducing the need for immediate plasma preparation after venipuncture, thereby facilitating the ease of blood collection and sample preparation for clinical research. However, the majority of cell stabilizing reagents have not been formally tested for their ability to preserve circulating plasma tumor DNA.
  
  
  METHODS
  In this study, we compared the properties of two cell stabilizing reagents, the cell-free DNA BCT tube and the PAXgene tube, by collecting blood samples from metastatic breast cancer patients and measuring genome equivalents of plasma DNA by droplet digital PCR. We compared wild type PIK3CA genome equivalents and also assayed for two PIK3CA hotspot mutations, E545K and H1047R.
  
  
  RESULTS
  Our results demonstrate that blood stored for 7 days in BCT tubes did not show evidence of cell lysis, whereas PAXgene tubes showed an order of magnitude increase in genome equivalents, indicative of considerable cellular lysis.
  
  
  CONCLUSIONS
  We conclude that BCT tubes can prevent lysis and cellular release of genomic DNA of blood samples from cancer patients when stored at room temperature, and could therefore be of benefit for blood specimen collections in clinical trials.
authors.affiliation: The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Patricia Valda
authors.initials: PV
authors.lastname: Toro
authors.affiliation: The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Bracha
authors.initials: B
authors.lastname: Erlanger
authors.affiliation: The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Julia A
authors.initials: JA
authors.lastname: Beaver
authors.affiliation: The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Rory L
authors.initials: RL
authors.lastname: Cochran
authors.affiliation: The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Dustin A
authors.initials: DA
authors.lastname: VanDenBerg
authors.affiliation: The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Yakim
authors.affiliation: The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Karen
authors.initials: K
authors.lastname: Cravero
authors.affiliation: The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: David
authors.initials: D
authors.lastname: Chu
authors.affiliation: The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Zabransky
authors.affiliation: The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Hong Yuen
authors.initials: HY
authors.lastname: Wong
authors.affiliation: The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Sarah
authors.initials: S
authors.lastname: Croessmann
authors.affiliation: The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Heather
authors.initials: H
authors.lastname: Parsons
authors.affiliation: The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; The Brady Urologic Institute, Department of Urology, USA.
authors.forename: Paula J
authors.initials: PJ
authors.lastname: Hurley
authors.affiliation: The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Josh
authors.initials: J
authors.lastname: Lauring
authors.affiliation: The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; The Whiting School of Engineering, Department of Chemical and Biomolecular Engineering, The Johns Hopkins University, Baltimore, MD, USA. Electronic address: bpark2@jhmi.edu.
authors.forename: Ben Ho
authors.initials: BH
authors.lastname: Park
mesh_terms: D014408:Biomarkers, Tumor / Q000097:blood* / Q000235:genetics / Q000378:metabolism; D001774:Blood Chemical Analysis; D001943:Breast Neoplasms / Q000097:blood* / Q000378:metabolism; D002173:Cancer Care Facilities; D058534:Class I Phosphatidylinositol 3-Kinases; D004273:DNA, Neoplasm / Q000097:blood*; D005260:Female; D006461:Hemolysis; D006801:Humans; D008832:Microchemistry / Q000379:methods; D009154:Mutation; D009362:Neoplasm Metastasis; D018962:Phlebotomy / Q000295:instrumentation*; D019869:Phosphatidylinositol 3-Kinases / Q000097:blood / Q000235:genetics / Q000378:metabolism; D010949:Plasma / Q000737:chemistry; D016133:Polymerase Chain Reaction; D011446:Prospective Studies; D012815:Signal Processing, Computer-Assisted
chemical_list: D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; D019869:Phosphatidylinositol 3-Kinases; D058534:Class I Phosphatidylinositol 3-Kinases; C484760:PIK3CA protein, human
keywords: Cell stabilizing tube; Circulating tumor DNA; Droplet digital PCR; Plasma tumor DNA