title: Antisense angiopoietin-1 inhibits tumorigenesis and angiogenesis of gastric cancer.
abstract: OBJECTIVE
  To investigate the effect of angiopoietin-1 (Ang-1) on biological behaviors in vitro and tumorigenesis and angiogenesis in vitro of human gastric cancer cells.
  
  
  METHODS
  Human full-length Ang-1 gene was cloned from human placental tissues by RT-PCR method. Recombinant human Ang-1 antisense eukaryotic expression vector was constructed by directional cloning, and transfected by lipofectin method into human gastric cancer line SGC7901 with high Ang-1 expression level. Inhibition efficiency was confirmed by semi- quantitative PCR and Western blot method. Cell growth curve and cell cycle were observed with MTT assays and flow cytometry, respectively. Nude mice tumorigenicity test was employed to compare in vitro tumorigenesis of cells with Ang-1 suppression. Microvessel density (MVD) of implanted tumor tissues was analyzed by immunohistochemistry for factor VIII staining.
  
  
  RESULTS
  Full-length Ang-1 gene was successfully cloned and stable transfectants were established, namely 7Ang1- for antisenseìand 7901P for empty vector transfected. 7Ang1- cells showed down-regulated Ang-1 expression, while its in vitro proliferation and cell cycle distribution were not significantly changed. In contrast, xenograft of 7Ang1- cells in nude mice had lower volume and weight than those of 7901P after 30 days' implantation (P<0.01, 293.00+/-95.54 mg vs. 624.00+/-77.78 mg) accompanied with less vessel formation with MVD 6.00+/-1.73 compared to 7901P group 8.44+/-1.33 (P<0.01).
  
  
  CONCLUSIONS
  Ang-1 may play an important role in tumorigenesis and angiogenesis of gastric cancer, and targeting its expression may be beneficial for the therapy of gastric cancer.
authors: Institute of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China.
authors: Jun
authors: J
authors: Wang
authors: Kai-Chun
authors: KC
authors: Wu
authors: De-Xin
authors: DX
authors: Zhang
authors: Dai-Ming
authors: DM
authors: Fan