title: Increased Akt and phosphorylated Akt expression are associated with malignant biological features of prostate cancer in Japanese men.
abstract: OBJECTIVE
  To investigate the relationship between the expression of Akt (a serine/threonine kinase that plays a central role in tumorigenesis), phosphorylated Akt (p-Akt), prostate cancer tumour grade, androgen receptor (AR)-staining score, and Ki67 labelling index (LI) in Japanese men.
  
  
  METHODS
  The expression and activation of the cell survival protein Akt was analysed by immunohistochemical staining of paraffin-embedded tissue microarray sections of prostate carcinoma taken from 52 Japanese men who under radical prostatectomy. The correlation between the expression of Akt and p-Akt, and their relationship to primary Gleason grade, AR expression and Ki-67 LI was investigated.
  
  
  RESULTS
  The expression of Akt and p-Akt were positively related to primary Gleason grade (Fisher's exact test, P = 0.002 and P = 0.032, respectively). Both AR-staining score and Ki67 LI were were positively related to the expression of Akt (both P < 0.001) and p-Akt (P < 0.001 and P = 0.008, respectively). There was a significant positive correlation between the expression of Akt and p-Akt (Spearman's correlation, r = 0.644, P < 0.001).
  
  
  CONCLUSIONS
  Increased expression of both Akt and p-Akt were associated with higher tumour grade as well as a higher AR-staining score and Ki67 LI. These data indicate that Akt and p-Akt might be molecular markers for detecting malignant biological features of prostate cancer in the Japanese population.
authors.affiliation: Department of Urology, Kyoto University Graduate School of Medicine, Kyoto, Japan.
authors.forename: Yousuke
authors.initials: Y
authors.lastname: Shimizu
authors.forename: Takehiko
authors.initials: T
authors.lastname: Segawa
authors.forename: Takahiro
authors.initials: T
authors.lastname: Inoue
authors.forename: Taizo
authors.initials: T
authors.lastname: Shiraishi
authors.forename: Toru
authors.initials: T
authors.lastname: Yoshida
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Toda
authors.forename: Tomomi
authors.initials: T
authors.lastname: Yamada
authors.forename: Naoko
authors.initials: N
authors.lastname: Kinukawa
authors.forename: Naoki
authors.initials: N
authors.lastname: Terada
authors.forename: Takashi
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Hidefumi
authors.initials: H
authors.lastname: Kinoshita
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Kamoto
authors.forename: Eijiro
authors.initials: E
authors.lastname: Nakamura
authors.forename: Osamu
authors.initials: O
authors.lastname: Ogawa
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology* / Q000601:surgery; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism*; D018572:Disease-Free Survival; D006801:Humans; D007150:Immunohistochemistry; D007564:Japan; D019394:Ki-67 Antigen / Q000378:metabolism*; D008297:Male; D046228:Microarray Analysis; D008875:Middle Aged; D015999:Multivariate Analysis; D010766:Phosphorylation; D017430:Prostate-Specific Antigen / Q000097:blood; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000473:pathology* / Q000601:surgery; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D011944:Receptors, Androgen / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D011944:Receptors, Androgen; D051057:Proto-Oncogene Proteins c-akt; D017430:Prostate-Specific Antigen