title: [Expression and significance of Notch1 and PTEN in gastric cancer].
abstract: OBJECTIVE
  Notch homolog 1 (Notch1) belongs to the Notch family of transmembrane receptors and plays an important role in cell differentiation. Notch1 plays a profound role in carcinogenesis and can be both oncogenic and tumor suppressive. However, the correlation of Notch1 expression to clinicopathologic features of gastric cancer is unclear. This study was to investigate the expression and significance of Notch1 and PTEN in gastric cancer.
  
  
  METHODS
  The expression of Notch1 and PTEN in a tissue microarray containing 168 spots of gastric cancer tissue and 27 spots of normal gastric tissue was detected by SP immunohistochemistry. The correlation of Notch1 expression to PTEN expression, and their correlations to the clinicophathologic features of gastric cancer were analyzed.
  
  
  RESULTS
  The positive rate of Notch1 was significantly higher in gastric cancer than in normal gastric tissue (61.9% vs. 25.9%, P<0.05), and closely related to tumor size (P<0.01), differentiation grade (P<0.01), depth of invasion (P<0.01) and vessel invasion (P<0.05). The positive rate of PTEN was significantly lower in gastric cancer than in normal gastric tissue (47.0% vs. 92.6%, P<0.01), and related to tumor size (P<0.01), differentiation grade (P<0.05), depth of invasion (P<0.01), vessel invasion (P<0.05), lymph node metastasis (P<0.05) and distant metastasis (P<0.05). The expression of Notch1 was negatively correlated to that of PTEN (r=-0.170, P<0.05). The 3-year survival rate was significantly higher in Notch1-negative patients than in Notch1-positive patients (78.0% vs. 34.0%, P<0.01), and was significantly higher in PTEN-positive patients than in PTEN-negative patients (62.0% vs.38.0%, P<0.01). COX regression analysis showed that Notch1 expression was an independent prognostic factor of gastric cancer.
  
  
  CONCLUSIONS
  The dys-regulation of PTEN and Notch1 expression may correlate to the occurrence and development of gastric cancer. Notch1 may be a novel prognostic marker of gastric cancer.
authors.affiliation: Department of Oncology, Shanghai First People's Hospital,Shanghai Jiaotong University, Shanghai, 200080, PR China.
authors.forename: Da-Wei
authors.initials: DW
authors.lastname: Li
authors.forename: Qing
authors.initials: Q
authors.lastname: Wu
authors.forename: Zhi-Hai
authors.initials: ZH
authors.lastname: Peng
authors.forename: Zhao-Rui
authors.initials: ZR
authors.lastname: Yang
authors.forename: Yi
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D005753:Gastric Mucosa / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D051059:PTEN Phosphohydrolase / Q000378:metabolism*; D016016:Proportional Hazards Models; D051881:Receptor, Notch1 / Q000378:metabolism*; D013270:Stomach / Q000473:pathology; D013274:Stomach Neoplasms / Q000378:metabolism* / Q000473:pathology; D015996:Survival Rate; D046888:Tissue Array Analysis
chemical_list: C497761:NOTCH1 protein, human; D051881:Receptor, Notch1; D051059:PTEN Phosphohydrolase; C494929:PTEN protein, human