title: Downregulation of CD24 inhibits invasive growth, facilitates apoptosis and enhances chemosensitivity in gastric cancer AGS cells.
abstract: OBJECTIVE
  The human CD24 antigen is a small heavily glycosylated cell surface protein, which is expressed in a large variety of solid tumors,including gastric cancer. Enriched on the surface of many tumor cells,CD24 promotes tumor growth,invasion and metastasis and confers resistance to some chemotherapeutic drugs.In this study, we investigated the possible effect of CD24 suppression on proliferation, apoptosis, migration, invasion and chemosensitivity of gastric cancer (GC) cells.
  
  
  METHODS
  We down-regulated CD24 expression by RNA interference and investigated the effects on proliferation, apoptosis, chemosensitivity to doxorubicin, malignant and metastatic potential of a human gastric cancer cell line, AGS, CD24-suppressed clones, AGS-CD24-siRNA-C2, AGS-CD24-siRNA-C4 and AGS-CD24-siRNA-C5 in vitro. We evaluated the effects of CD24 suppression in vivo on xenograft tumor growth and metastatic properties following tail iv AGS-CD24-siRNA-C2, AGS-CD24-siRNA-C4 and AGS-CD24-siRNA-C5 clones. We also investigated the effect of CD24-siRNA followed by doxorubicin administration treatment on the xenograft tumor growth.
  
  
  RESULTS
  CD24 suppressed showed significantly decreased proliferation, invasion and increased apoptosis as well as increased chemosensitivity to doxorubicin in vitro and in vivo.
  
  
  CONCLUSIONS
  CD24 involves in proliferation, invasion and chemosensitivity of human gastric cancer cell line AGS, and that down-regulation of CD24 protein expression decreases the metastatic potential and increases chemosensitivity of gastric cancer (GC) cells. Thus, CD24 may be a promising therapeutic target for gastric cancer.
authors.affiliation: Department of General Surgery, Qingdao University, Qingdao, Shandong, Reople's Republic of China.
authors.forename: X-L
authors.initials: XL
authors.lastname: Jiao
authors.forename: C
authors.initials: C
authors.lastname: Zhao
authors.forename: M
authors.initials: M
authors.lastname: Niu
authors.forename: D
authors.initials: D
authors.lastname: Chen
mesh_terms: D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D000970:Antineoplastic Agents / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D051927:CD24 Antigen / Q000096:biosynthesis / Q000235:genetics*; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D015536:Down-Regulation / Q000187:drug effects*; D004317:Doxorubicin / Q000494:pharmacology; D019008:Drug Resistance, Neoplasm / Q000187:drug effects*; D006801:Humans; D020287:In Situ Nick-End Labeling; D007202:Indicators and Reagents; D051379:Mice; D009361:Neoplasm Invasiveness; D034741:RNA, Small Interfering / Q000235:genetics; D013274:Stomach Neoplasms / Q000235:genetics* / Q000473:pathology*; D023041:Xenograft Model Antitumor Assays
chemical_list: D000903:Antibiotics, Antineoplastic; D000970:Antineoplastic Agents; D051927:CD24 Antigen; D007202:Indicators and Reagents; D034741:RNA, Small Interfering; D004317:Doxorubicin