title: A novel multiplexed immunoassay identifies CEA, IL-8 and prolactin as prospective markers for Dukes' stages A-D colorectal cancers.
abstract: BACKGROUND
  Current methods widely deployed for colorectal cancers (CRC) screening lack the necessary sensitivity and specificity required for population-based early disease detection. Cancer-specific protein biomarkers are thought to be produced either by the tumor itself or other tissues in response to the presence of cancers or associated conditions. Equally, known examples of cancer protein biomarkers (e.g., PSA, CA125, CA19-9, CEA, AFP) are frequently found in plasma at very low concentration (pg/mL-ng/mL). New sensitive and specific assays are therefore urgently required to detect the disease at an early stage when prognosis is good following surgical resection. This study was designed to meet the longstanding unmet clinical need for earlier CRC detection by measuring plasma candidate biomarkers of cancer onset and progression in a clinical stage-specific manner. EDTA plasma samples (1 μL) obtained from 75 patients with Dukes' staged CRC or unaffected controls (age and sex matched with stringent inclusion/exclusion criteria) were assayed for expression of 92 human proteins employing the Proseek® Multiplex Oncology I proximity extension assay. An identical set of plasma samples were analyzed utilizing the Bio-Plex Pro™ human cytokine 27-plex immunoassay.
  
  
  RESULTS
  Similar quantitative expression patterns for 13 plasma antigens common to both platforms endorsed the potential efficacy of Proseek as an immune-based multiplex assay for proteomic biomarker research. Proseek found that expression of Carcinoembryonic Antigen (CEA), IL-8 and prolactin are significantly correlated with CRC stage.
  
  
  CONCLUSIONS
  CEA, IL-8 and prolactin expression were found to identify between control (unaffected), non-malignant (Dukes' A + B) and malignant (Dukes' C + D) stages.
authors.affiliation: Australian School of Advanced Medicine, Faculty of Medicine and Human Sciences, Macquarie University, Rm1, Level 1, 75 Talavera Road, Sydney, NSW 2109 Australia.
authors.forename: Sadia
authors.initials: S
authors.lastname: Mahboob
authors.affiliation: Australian School of Advanced Medicine, Faculty of Medicine and Human Sciences, Macquarie University, Rm1, Level 1, 75 Talavera Road, Sydney, NSW 2109 Australia.
authors.forename: Seong Beom
authors.initials: SB
authors.lastname: Ahn
authors.affiliation: Australian School of Advanced Medicine, Faculty of Medicine and Human Sciences, Macquarie University, Rm1, Level 1, 75 Talavera Road, Sydney, NSW 2109 Australia.
authors.forename: Harish R
authors.initials: HR
authors.lastname: Cheruku
authors.affiliation: Australian School of Advanced Medicine, Faculty of Medicine and Human Sciences, Macquarie University, Rm1, Level 1, 75 Talavera Road, Sydney, NSW 2109 Australia.
authors.forename: David
authors.initials: D
authors.lastname: Cantor
authors.affiliation: Olink Bioscience, Dag Hammarskjölds Väg, 54A, 75183 Uppsala, Sweden.
authors.forename: Emma
authors.initials: E
authors.lastname: Rennel
authors.affiliation: Olink Bioscience, Dag Hammarskjölds Väg, 54A, 75183 Uppsala, Sweden.
authors.forename: Simon
authors.initials: S
authors.lastname: Fredriksson
authors.affiliation: Olink Bioscience, Dag Hammarskjölds Väg, 54A, 75183 Uppsala, Sweden.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Edfeldt
authors.affiliation: Australian Proteome Analysis Facility, Macquarie University, Sydney, NSW 2109 Australia.
authors.forename: Edmond J
authors.initials: EJ
authors.lastname: Breen
authors.affiliation: Australian Proteome Analysis Facility, Macquarie University, Sydney, NSW 2109 Australia.
authors.forename: Alamgir
authors.initials: A
authors.lastname: Khan
authors.affiliation: Department of Chemistry and Biomolecular Sciences, Faculty of Science, Macquarie University, Sydney, NSW 2109 Australia.
authors.forename: Abidali
authors.initials: A
authors.lastname: Mohamedali
authors.affiliation: School of Science and Health, University of Western Sydney, NSW, Australia.
authors.forename: Md Golam
authors.initials: MG
authors.lastname: Muktadir
authors.affiliation: Department of Chemistry and Biomolecular Sciences, Faculty of Science, Macquarie University, Sydney, NSW 2109 Australia.
authors.forename: Shoba
authors.initials: S
authors.lastname: Ranganathan
authors.affiliation: Australian School of Advanced Medicine, Faculty of Medicine and Human Sciences, Macquarie University, Rm1, Level 1, 75 Talavera Road, Sydney, NSW 2109 Australia.
authors.forename: Sock-Hwee
authors.initials: SH
authors.lastname: Tan
authors.affiliation: Department of Biochemistry and Molecular Biology, Monash University, Clayton Campus, Melbourne, VIC 3800 Australia.
authors.forename: Edouard
authors.initials: E
authors.lastname: Nice
authors.affiliation: Australian School of Advanced Medicine, Faculty of Medicine and Human Sciences, Macquarie University, Rm1, Level 1, 75 Talavera Road, Sydney, NSW 2109 Australia.
authors.forename: Mark S
authors.initials: MS
authors.lastname: Baker
keywords: Colorectal cancer; Multiplex immunoassay; Plasma biomarker