title: Biochemical characterization of riboflavin carrier protein (RCP) in prostate cancer.
abstract: Riboflavin carrier protein (RCP) is a growth- and development-specific protein. Here, we characterized the expression of this protein in prostate cancer by polyclonal and monoclonal antibodies against chicken RCP. RCP was localized to both androgen-dependent and independent prostate cancer cell lines. Compared to controls, RCP was over-expressed in all 45 prostate adenocarcinomas, irrespective of the Gleason's score or the stage of the disease. The identified RCP had a molecular weight of 38 kDa, similar to RCP purified from chicken. Presence of this protein was also confirmed by siRNA inhibition analysis. Antibodies to chicken RCP inhibited incorporation of tritiated thymidine into DNA and prevented riboflavin uptake in PC3 prostate cancer cells, suggesting a critical function of this protein in prostate cancer cell growth. These data suggest that RCP can be used as a tumor biomarker in prostate cancer.
authors.affiliation: Department of Biochemistry, Louisiana State University Health Sciences Center, New Orleans, LA, USA.
authors.forename: Tanya
authors.initials: T
authors.lastname: Johnson
authors.forename: Allal
authors.initials: A
authors.lastname: Ouhtit
authors.forename: Rajiv
authors.initials: R
authors.lastname: Gaur
authors.forename: Augusta
authors.initials: A
authors.lastname: Fernando
authors.forename: Paul
authors.initials: P
authors.lastname: Schwarzenberger
authors.forename: Joseph
authors.initials: J
authors.lastname: Su
authors.forename: Mohamed F
authors.initials: MF
authors.lastname: Ismail
authors.forename: Hassan I
authors.initials: HI
authors.lastname: El-Sayyad
authors.forename: Anjali
authors.initials: A
authors.lastname: Karande
authors.forename: Zakaria Abd
authors.initials: ZA
authors.lastname: Elmageed
authors.forename: Prakash
authors.initials: P
authors.lastname: Rao
authors.forename: Madhwa
authors.initials: M
authors.lastname: Raj
mesh_terms: D000595:Amino Acid Sequence; D015153:Blotting, Western; D045744:Cell Line, Tumor; D006801:Humans; D007150:Immunohistochemistry; D047468:Immunoprecipitation; D008297:Male; D026901:Membrane Transport Proteins / Q000378:metabolism*; D008969:Molecular Sequence Data; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000473:pathology; D034741:RNA, Small Interfering; D012256:Riboflavin / Q000378:metabolism; D013936:Thymidine / Q000378:metabolism
chemical_list: D026901:Membrane Transport Proteins; D034741:RNA, Small Interfering; C019079:riboflavin-binding protein; D012256:Riboflavin; D013936:Thymidine