title: Increased mRNA expression of epidermal growth factor receptor, human epidermal receptor, and survivin in human gastric cancer after the surgical stress of laparotomy versus carbon dioxide pneumoperitoneum in a murine model.
abstract: BACKGROUND
  Surgical impact may be associated with enhanced tumor growth and chemoresistance. This study aimed to evaluate the effect of surgical impact on the mRNA expression of survivin, epidermal growth factor receptor (EGFR), and human epidermal receptor (HER2) in tumors after pneumoperitoneum versus laparotomy.
  
  
  METHODS
  Nude mice were inoculated intraperitoneally with human gastric cancer cells (MKN45). Then laparotomy, carbon dioxide (CO(2)) pneumoperitoneum, and anesthesia alone were performed randomly, after which EGFR, HER2, and survivin mRNA expression using reverse transcription-polymerase chain reaction (RT-PCR) was evaluated.
  
  
  RESULTS
  The expression of EGFR and HER2 mRNA increased significantly after the experiment. However, it was higher after laparotomy than after CO(2) pneumoperitoneum at almost all examined time points. Survivin mRNA expression increased significantly in the first 48 h, then returned to the control level. It was higher after laparotomy than after CO(2) pneumoperitoneum 48 h after the surgical procedures.
  
  
  CONCLUSIONS
  The expression of EGFR, HER2, and survivin increased after each surgical procedure. However it was lower after CO(2) pneumoperitoneum than after laparotomy. This might be associated with changes in the chemosensitivity of the remnant cancer cells after surgery, supporting the use of minimally invasive surgery for cancer.
authors.affiliation: Department of Gastroenterological Surgery, Oita University Faculty of Medicine, 1-1 Idaigaoka, Yufu, Oita 879-5593, Japan. anwar71@med.oita-u.ac.jp
authors.forename: Anwar Tawfik
authors.initials: AT
authors.lastname: Amin
authors.forename: Norio
authors.initials: N
authors.lastname: Shiraishi
authors.forename: Shigeo
authors.initials: S
authors.lastname: Ninomiya
authors.forename: Masaaki
authors.initials: M
authors.lastname: Tajima
authors.forename: Masafumi
authors.initials: M
authors.lastname: Inomata
authors.forename: Seigo
authors.initials: S
authors.lastname: Kitano
mesh_terms: D000818:Animals; D002245:Carbon Dioxide / Q000008:administration & dosage; D066246:ErbB Receptors / Q000096:biosynthesis / Q000235:genetics*; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins; D010535:Laparoscopy / Q000379:methods; D007813:Laparotomy / Q000379:methods*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008869:Microtubule-Associated Proteins / Q000096:biosynthesis / Q000235:genetics*; D009374:Neoplasms, Experimental; D011028:Pneumoperitoneum, Artificial / Q000379:methods*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics*; D018719:Erb-b2 Receptor Tyrosine Kinases; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000601:surgery; D013314:Stress, Mechanical; D000077022:Survivin; D014407:Tumor Cells, Cultured
chemical_list: D002245:Carbon Dioxide; D066246:ErbB Receptors; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins; D012333:RNA, Messenger; D018719:Erb-b2 Receptor Tyrosine Kinases; D000077022:Survivin; C107489:BIRC5 protein, human