title: Dominant B-cell epitopes from cancer/stem cell antigen SOX2 recognized by serum samples from cancer patients.
abstract: Human sex determining region Y-box 2 (SOX2) is an important transcriptional factor involved in the pluripotency and stemness of human embryonic stem cells. SOX2 plays important roles in maintaining cancer stem cell activities of melanoma and cancers of the brain, prostate, breast, and lung. SOX2 is also a lineage survival oncogene for squamous cell carcinoma of the lung and esophagus. Spontaneous cellular and humoral immune responses against SOX2 present in cancer patients classify it as a tumor-associated antigen (TAA) shared by lung cancer, glioblastoma, and prostate cancer among others. In this study, B-cell epitopes were predicted using computer-assisted algorithms. Synthetic peptides based on the prediction were screened for recognition by serum samples from cancer patients using ELISA. Two dominant B-cell epitopes, SOX2:52-87 and SOX2:98-124 were identified. Prostate cancer, glioblastoma and lung cancer serum samples that recognized the above SOX2 epitopes also recognized the full-length protein based on Western blot. These B-cell epitopes may be used in assessing humoral immune responses against SOX2 in cancer immunotherapy and stem cell-related transplantation.
authors.affiliation: Department of Urology, David Geffen School of Medicine at UCLA Los Angeles, CA 90095, USA.
authors.forename: Julia
authors.initials: J
authors.lastname: Shih
authors.affiliation: Western University of Health Sciences Pomona, CA 91766, USA.
authors.forename: Munira
authors.initials: M
authors.lastname: Rahman
authors.affiliation: Department of Medicine, David Geffen School of Medicine at UCLA Los Angeles, CA 90095, USA.
authors.forename: Quang T
authors.initials: QT
authors.lastname: Luong
authors.affiliation: Department of Urology, David Geffen School of Medicine at UCLA Los Angeles, CA 90095, USA.
authors.forename: Shirley H
authors.initials: SH
authors.lastname: Lomeli
authors.affiliation: Department of Urology, David Geffen School of Medicine at UCLA Los Angeles, CA 90095, USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: Riss
authors.affiliation: Department of Neurosurgery, David Geffen School of Medicine at UCLA Los Angeles, CA 90095, USA.
authors.forename: Robert M
authors.initials: RM
authors.lastname: Prins
authors.affiliation: Department of Molecular Biology and Genetics, Bilkent University Ankara 06800, Turkey.
authors.forename: Ali O
authors.initials: AO
authors.lastname: Gure
authors.affiliation: Department of Urology, David Geffen School of Medicine at UCLA Los Angeles, CA 90095, USA.
authors.forename: Gang
authors.initials: G
authors.lastname: Zeng
keywords: autoantibody; biomarkers; cancer stem cell; iPS cell; pluripotent stem cell