title: DJ-1 is activated in medulloblastoma and is associated with cell proliferation and differentiation.
abstract: BACKGROUND
  DJ-1 is a key regulator in human tumorigenesis, including brain malignancies. The mechanisms by which DJ-1 contributes to the pathogenesis of medulloblastoma (MB) remain unclear, and its impact on the prognosis for patients with MB has not been identified. The aim of this study was to determine whether the DJ-1 protein is associated with tumorigenesis of MBs, and whether DJ-1 is a valuable factor for predicting the prognosis of patients with MB.
  
  
  METHODS
  We collected 66 pairs of MB and adjacent normal cerebellum samples. Expression of DJ-1, Ser 473-phosphorylated-Akt (p-Akt), PTEN, and Ki-67 (MIB-1) was detected by immunohistochemical staining, and the correlation of these immunostaining results with the clinicopathological features of patients with MB was determined.
  
  
  RESULTS
  High DJ-1 expression (48.5%, 32/66) in tumor cells of MBs was significantly associated with the classic MB variant (P = 0.003), high proliferative activity (P = 0.002) and undifferentiated tumor (P = 0.001), whereas high p-Akt expression (56.1%, 37/66) was associated with tumor metastasis stage (P = 0.007), undifferentiated tumor (P = 0.007), and high-risk tumor (P = 0.002). High DJ-1 expression also correlated with high p-Akt expression and high MIB-1 index. However, only high levels of DJ-1(P = 0.009) and high MIB-1 index (P = 0.001) were strong independent prognostic factors associated with worse overall survival.
  
  
  CONCLUSIONS
  Although the validity of the preliminary data in this study needs to be confirmed by a larger number of cases, our study indicates that DJ-1, PTEN, and p-Akt might play important roles in cell proliferation and differentiation of MBs. The evaluation of expression of DJ-1 and related proteins might be useful for predicting the prognosis of patients with MB.
authors.forename: Jia-Ping
authors.initials: JP
authors.lastname: Lin
authors.forename: Bin-Cai
authors.initials: BC
authors.lastname: Pan
authors.forename: Bin
authors.initials: B
authors.lastname: Li
authors.forename: Yang
authors.initials: Y
authors.lastname: Li
authors.forename: Xiao-Ying
authors.initials: XY
authors.lastname: Tian
authors.affiliation: Department of Pathology, The First Affiliated Hospital, Sun Yat-sen University, 58, Zhongshan Road II, Guangzhou 510080, China. lizhi@mail.sysu.edu.cn.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Li
mesh_terms: D002454:Cell Differentiation; D049109:Cell Proliferation; D002528:Cerebellar Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007124:Immunoenzyme Techniques; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D008207:Lymphatic Metastasis; D008297:Male; D008527:Medulloblastoma / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D009364:Neoplasm Recurrence, Local / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D009367:Neoplasm Staging; D015513:Oncogene Proteins / Q000378:metabolism*; D011379:Prognosis; D000071617:Protein Deglycase DJ-1; D015996:Survival Rate
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D015513:Oncogene Proteins; C105131:PARK7 protein, human; D000071617:Protein Deglycase DJ-1