title: The expression profile of phosphatidylinositol in high spatial resolution imaging mass spectrometry as a potential biomarker for prostate cancer.
abstract: High-resolution matrix-assisted laser desorption/ionization imaging mass spectrometry (HR-MALDI-IMS) is an emerging application for the comprehensive and detailed analysis of the spatial distribution of ionized molecules in situ on tissue slides. HR-MALDI-IMS in negative mode in a mass range of m/z 500-1000 was performed on optimal cutting temperature (OCT) compound-embedded human prostate tissue samples obtained from patients with prostate cancer at the time of radical prostatectomy. HR-MALDI-IMS analysis of the 14 samples in the discovery set identified 26 molecules as highly expressed in the prostate. Tandem mass spectrometry (MS/MS) showed that these molecules included 14 phosphatidylinositols (PIs), 3 phosphatidylethanolamines (PEs) and 3 phosphatidic acids (PAs). Among the PIs, the expression of PI(18:0/18:1), PI(18:0/20:3) and PI(18:0/20:2) were significantly higher in cancer tissue than in benign epithelium. A biomarker algorithm for prostate cancer was formulated by analyzing the expression profiles of PIs in cancer tissue and benign epithelium of the discovery set using orthogonal partial least squares discriminant analysis (OPLS-DA). The sensitivity and specificity of this algorithm for prostate cancer diagnosis in the 24 validation set samples were 87.5 and 91.7%, respectively. In conclusion, HR-MALDI-IMS identified several PIs as being more highly expressed in prostate cancer than benign prostate epithelium. These differences in PI expression profiles may serve as a novel diagnostic tool for prostate cancer.
authors.affiliation: Department of Urology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Goto
authors.affiliation: Department of Urology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Terada
authors.affiliation: Department of Urology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Inoue
authors.affiliation: Department of Urology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Nakayama
authors.affiliation: Department of Urology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Okada
authors.affiliation: Department of Urology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yoshikawa
authors.affiliation: Department of Urology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Miyazaki
authors.affiliation: Department of Urology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Uegaki
authors.affiliation: Department of Diagnostic Pathology, Kyoto University Hospital, Kyoto, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Sumiyoshi
authors.affiliation: Department of Urology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kobayashi
authors.affiliation: Department of Urology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Tomomi
authors.initials: T
authors.lastname: Kamba
authors.affiliation: Department of Urology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Yoshimura
authors.affiliation: Department of Urology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Ogawa
mesh_terms: D000368:Aged; D000465:Algorithms; D014408:Biomarkers, Tumor / Q000302:isolation & purification* / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D010712:Phosphatidic Acids / Q000302:isolation & purification* / Q000378:metabolism; D010714:Phosphatidylethanolamines / Q000302:isolation & purification* / Q000378:metabolism; D010716:Phosphatidylinositols / Q000302:isolation & purification* / Q000378:metabolism; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000378:metabolism; D012680:Sensitivity and Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods
chemical_list: D014408:Biomarkers, Tumor; D010712:Phosphatidic Acids; D010714:Phosphatidylethanolamines; D010716:Phosphatidylinositols