title: Differential expression of anterior gradient gene AGR2 in prostate cancer.
abstract: BACKGROUND
  The protein AGR2 is a putative member of the protein disulfide isomerase family and was first identified as a homolog of the Xenopus laevis gene XAG-2. AGR2 has been implicated in a number of human cancers. In particular, AGR2 has previously been found to be one of several genes that encode secreted proteins showing increased expression in prostate cancer cells compared to normal prostatic epithelium.
  
  
  METHODS
  Gene expression levels of AGR2 were examined in prostate cancer cells by microarray analysis. We further examined the relationship of AGR2 protein expression to histopathology and prostate cancer outcome on a population basis using tissue microarray technology.
  
  
  RESULTS
  At the RNA and protein level, there was an increase in AGR2 expression in adenocarcinoma of the prostate compared to morphologically normal prostatic glandular epithelium. Using a tissue microarray, this enhanced AGR2 expression was seen as early as premalignant PIN lesions. Interestingly, within adenocarcinoma samples, there was a slight trend toward lower levels of AGR2 with increasing Gleason score. Consistent with this, relatively lower levels of AGR2 were highly predictive of disease recurrence in patients who had originally presented with high-stage primary prostate cancer (P = 0.009).
  
  
  CONCLUSIONS
  We have shown for the first time that despite an increase in AGR2 expression in prostate cancer compared to non-malignant cells, relatively lower levels of AGR2 are highly predictive of disease recurrence following radical prostatectomy.
authors.affiliation: Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, 10833 Le Conte Ave, Los Angeles, CA 90095, USA.
authors.forename: Erin L
authors.initials: EL
authors.lastname: Maresh
authors.forename: Vei
authors.initials: V
authors.lastname: Mah
authors.forename: Mohammad
authors.initials: M
authors.lastname: Alavi
authors.forename: Steve
authors.initials: S
authors.lastname: Horvath
authors.forename: Lora
authors.initials: L
authors.lastname: Bagryanova
authors.forename: Emily S
authors.initials: ES
authors.lastname: Liebeskind
authors.forename: Laura A
authors.initials: LA
authors.lastname: Knutzen
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhou
authors.forename: David
authors.initials: D
authors.lastname: Chia
authors.forename: Alvin Y
authors.initials: AY
authors.lastname: Liu
authors.forename: Lee
authors.initials: L
authors.lastname: Goodglick
mesh_terms: D000230:Adenocarcinoma / Q000201:enzymology* / Q000235:genetics / Q000401:mortality / Q000556:secondary / Q000601:surgery; D000368:Aged; D020869:Gene Expression Profiling / Q000379:methods; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D015141:Los Angeles; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009088:Mucoproteins; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D020411:Oligonucleotide Array Sequence Analysis; D015513:Oncogene Proteins; D011230:Precancerous Conditions / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D016016:Proportional Hazards Models; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000201:enzymology* / Q000235:genetics / Q000401:mortality / Q000473:pathology / Q000601:surgery; D011506:Proteins / Q000032:analysis* / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D018570:Risk Assessment; D012307:Risk Factors; D046888:Tissue Array Analysis / Q000379:methods; D016896:Treatment Outcome
chemical_list: C502296:AGR2 protein, human; D009088:Mucoproteins; D015513:Oncogene Proteins; D011506:Proteins; D012333:RNA, Messenger