title: Identification of novel candidate biomarkers of epithelial ovarian cancer by profiling the secretomes of three-dimensional genetic models of ovarian carcinogenesis.
abstract: Epithelial ovarian cancer (EOC) is still considered the most lethal gynecological malignancy and improved early detection of ovarian cancer is crucial to improving patient prognoses. To address this need, we tested whether candidate EOC biomarkers can be identified using three-dimensional (3D) in vitro models. We quantified changes in the abundance of secreted proteins in a 3D genetic model of early-stage EOC, generated by expressing CMYC and KRAS(G) (12) (V) in TERT-immortalized normal ovarian epithelial cells. Cellular proteins were labeled in live cells using stable isotopic amino acid analogues, and secreted proteins identified and quantified using liquid chromatography-tandem mass spectrometry. Thirty-seven and 55 proteins were differentially expressed by CMYC and CMYC+KRAS(G) (12) (V) expressing cells respectively (p < 0.05; >2-fold). We evaluated expression of the top candidate biomarkers in ∼210 primary EOCs: CHI3L1 and FKBP4 are both expressed by >96% of primary EOCs, and FASN and API5 are expressed by 86 and 75% of cases. High expression of CHI3L1 and FKBP4 was associated with worse patient survival (p = 0.042 and p = 0.002, respectively). Expression of LGALS3BP was positively associated with recurrence (p = 0.0001) and suboptimal debulking (p = 0.018) suggesting that these proteins may be novel prognostic biomarkers. Furthermore, within early stage tumours (I/II), high expression of API5, CHI3L1 and FASN was associated with high tumour grade (p = 3 × 10(-4) , p = 0.016, p = 0.010, respectively). We show in vitro cell biology models of early-stage cancer development can be used to identify novel candidate biomarkers for disease, and report the identification of proteins that represent novel potential candidate diagnostic and prognostic biomarkers for this highly lethal disease.
authors.affiliation: Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA.
authors.forename: Kate
authors.initials: K
authors.lastname: Lawrenson
authors.affiliation: Departments of Medicine and Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA.
authors.forename: Paulette
authors.initials: P
authors.lastname: Mhawech-Fauceglia
authors.affiliation: Cancer Proteomics Group, Institute for Women's Health, University College London, London, United Kingdom.
authors.forename: Jenny
authors.initials: J
authors.lastname: Worthington
authors.affiliation: Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA.
authors.forename: Tassja J
authors.initials: TJ
authors.lastname: Spindler
authors.affiliation: Cancer Proteomics Group, Institute for Women's Health, University College London, London, United Kingdom.
authors.forename: Darragh
authors.initials: D
authors.lastname: O'Brien
authors.affiliation: Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA.
authors.forename: Janet M
authors.initials: JM
authors.lastname: Lee
authors.affiliation: Cancer Proteomics Group, Institute for Women's Health, University College London, London, United Kingdom.
authors.forename: Georgia
authors.initials: G
authors.lastname: Spain
authors.affiliation: Departments of Medicine and Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA.
authors.forename: Maryam
authors.initials: M
authors.lastname: Sharifian
authors.affiliation: Women's Health Integrated Research Center at Inova Health System, Gynecologic Cancer Center of Excellence, Annandale, VA.
authors.forename: Guisong
authors.initials: G
authors.lastname: Wang
authors.affiliation: Women's Health Integrated Research Center at Inova Health System, Gynecologic Cancer Center of Excellence, Annandale, VA.
authors.forename: Kathleen M
authors.initials: KM
authors.lastname: Darcy
authors.affiliation: Department of Obstetrics and Gynecology, Oregon Health and Science University, Portland, OR.
authors.forename: Tanja
authors.initials: T
authors.lastname: Pejovic
authors.affiliation: Biological and Forensic Science Department, University of Derby, Derby, United Kingdom.
authors.forename: Heidi
authors.initials: H
authors.lastname: Sowter
authors.affiliation: Cancer Proteomics Group, Institute for Women's Health, University College London, London, United Kingdom.
authors.forename: John F
authors.initials: JF
authors.lastname: Timms
authors.affiliation: Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA.
authors.forename: Simon A
authors.initials: SA
authors.lastname: Gayther
mesh_terms: D054392:Adipokines / Q000378:metabolism; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000378:metabolism*; D000077216:Carcinoma, Ovarian Epithelial; D045744:Cell Line, Tumor; D000071451:Chitinase-3-Like Protein 1; D054890:Fatty Acid Synthase, Type I / Q000378:metabolism; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D066298:In Vitro Techniques; D037102:Lectins / Q000378:metabolism; D008957:Models, Genetic; D009375:Neoplasms, Glandular and Epithelial / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D009687:Nuclear Proteins / Q000378:metabolism; D010051:Ovarian Neoplasms / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D011379:Prognosis; D040901:Proteomics / Q000379:methods*; D011518:Proto-Oncogene Proteins / Q000235:genetics* / Q000378:metabolism; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics* / Q000378:metabolism; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: C108386:API5 protein, human; D054392:Adipokines; D051017:Apoptosis Regulatory Proteins; D014408:Biomarkers, Tumor; C084533:CHI3L1 protein, human; D000071451:Chitinase-3-Like Protein 1; C117307:KRAS protein, human; D037102:Lectins; C489427:MYC protein, human; D009687:Nuclear Proteins; D011518:Proto-Oncogene Proteins; D016271:Proto-Oncogene Proteins c-myc; C518729:FASN protein, human; D054890:Fatty Acid Synthase, Type I; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins
keywords: 3D models; MAPK; SILAC; biomarkers; early detection; ovarian cancer