title: Impact of the surgical peritoneal environment on pre-implanted tumors on a molecular level: a syngeneic mouse model.
abstract: BACKGROUND
  We recently demonstrated that a CO(2) pneumoperitoneum at either a high or low IPP has few if any short term effects on peritoneal dissemination when tumors are well established before surgery. The objective of the present study was to evaluate the impact of the surgical peritoneal environment on pre-implanted tumors on a molecular level.
  
  
  METHODS
  On day 7, C57BJ6 mice received an intraperitoneal inoculation of a mouse ovarian cancer cell line (ID8). On day 0, mice were randomized into four groups: anesthesia alone, CO(2) pneumoperitoneum at a low (2 mm Hg) or high (8 mm Hg) IPP, or laparotomy. Groups were further subdivided into four groups and a laparotomy was performed to collect pre-implanted tumors on POD 1, 2, 7, or 14. Expression levels of beta-1 integrin, cMet, uPA, uPAR, and PAI-1 mRNA in pre-implanted nodules were measured using real-time PCR.
  
  
  RESULTS
  Expression levels of uPA, uPAR, and cMet mRNA were significantly higher in the laparotomy group than in the control group on POD 1. We detected significantly higher expression levels of uPAR and cMet in the laparotomy group than in the control group on PODs 2 and 7. There were no significant differences in the expression levels of any genes examined among the low IPP, anesthesia alone, and control groups on POD 1, 2, 7, or 14.
  
  
  CONCLUSIONS
  The impact of a CO(2) pneumoperitoneum at a low IPP on gene expression levels of pre-implanted tumors might be minimal until POD 14 in the present mouse model.
authors.affiliation: Université d'Auvergne-Clermont I, Centre d'endoscopy et des Nouvelles Techniques Interventionnelles (CENTI), Clermont-Ferrand, France. sachikoma@aol.com
authors.forename: Sachiko
authors.initials: S
authors.lastname: Matsuzaki
authors.forename: Anne-Sophie
authors.initials: AS
authors.lastname: Azuar
authors.forename: Gérard
authors.initials: G
authors.lastname: Mage
authors.forename: Michel
authors.initials: M
authors.lastname: Canis
mesh_terms: D000818:Animals; D002277:Carcinoma / Q000378:metabolism / Q000556:secondary* / Q000601:surgery; D045744:Cell Line, Tumor; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D051379:Mice; D008810:Mice, Inbred C57BL; D009366:Neoplasm Seeding; D009374:Neoplasms, Experimental; D010051:Ovarian Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D010534:Peritoneal Neoplasms / Q000378:metabolism / Q000556:secondary*; D010537:Peritoneum / Q000473:pathology; D011028:Pneumoperitoneum, Artificial / Q000009:adverse effects*; D011183:Postoperative Complications / Q000209:etiology* / Q000378:metabolism / Q000473:pathology; D014185:Transplantation, Isogeneic