title: Reduced expression of alpha-tocopherol-associated protein is associated with tumor cell proliferation and the increased risk of prostate cancer recurrence.
abstract: OBJECTIVE
  To examine the impact and prognostic significance of alpha-tocopherol associated protein (TAP) expression in a series of prostate cancer patients.
  
  
  METHODS
  Tissues from 87 patients underwent radical prostatectomy were examined for TAP expression by immunohistochemistry. The relationships of the staining results, the clinic pathological characteristics and the recurrence times were analyzed.
  
  
  RESULTS
  Compared with the adjacent areas of normal and benign glands, immunoreactivity of TAP was reduced in areas of prostate cancer. A lower TAP-positive cell number per mm(2) of the largest cancer area (defined as TAP-PN) was associated with higher clinical stage (r = -0.248, P = 0.0322). Inverse associations were found among the TAP-PN and positive lymph nodes (r = -0.231, P = 0.0325), preoperative prostate-specific antigen (PSA) levels (r = -0.423, P = 0.0043), tumor size (r= -0.315, P= 0.0210) and elevated tumor cell proliferation, which was indicated by the staining of Ki-67 (r = -0.308, P = 0.0026). TAP-PN was a significant predictor of recurrence univariately (P = 0.0006), as well as multivariately, adjusted for known markers including preoperative PSA, clinical stage, Gleason score, surgical margin, extra-prostatic extension, seminal vesicle invasion and lymph node metastasis (P = 0.0012).
  
  
  CONCLUSIONS
  Reduced expression of TAP was associated with the cell proliferation status of prostate cancer, adverse pathological parameters and the increased risk of recurrence.
authors.affiliation: Department of Urology, Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510630, China. xingqiaowen@yahoo.com
authors.forename: Xing-Qiao
authors.initials: XQ
authors.lastname: Wen
authors.forename: Xiao-Juan
authors.initials: XJ
authors.lastname: Li
authors.forename: Zu-Lan
authors.initials: ZL
authors.lastname: Su
authors.forename: Yong
authors.initials: Y
authors.lastname: Liu
authors.forename: Xiang-Fu
authors.initials: XF
authors.lastname: Zhou
authors.forename: Yu-Bin
authors.initials: YB
authors.lastname: Cai
authors.forename: Wen-Tao
authors.initials: WT
authors.lastname: Huang
authors.forename: Xin
authors.initials: X
authors.lastname: Gao
mesh_terms: D000368:Aged; D002352:Carrier Proteins / Q000096:biosynthesis* / Q000235:genetics; D049109:Cell Proliferation; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D019394:Ki-67 Antigen / Q000096:biosynthesis; D008074:Lipoproteins / Q000096:biosynthesis* / Q000235:genetics; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000209:etiology*; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000473:pathology; D015534:Trans-Activators / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D002352:Carrier Proteins; D019394:Ki-67 Antigen; D008074:Lipoproteins; C432422:SEC14L2 protein, human; D015534:Trans-Activators