title: CO2 environment influences the growth of cultured human cancer cells dependent on insufflation pressure.
abstract: BACKGROUND
  Experimental and clinical studies, have suggested that the CO2 pneumoperitoneum influences the development of intraabdominal tumor dissemination and port site metastases. Previous experiments performed both in vitro and in vivo have proved that CO2 insufflation stimulates malignant cell growth. Therefore, we designed a study to investigate the influence of CO2 insufflation administered at different pressures on the growth of cultured human tumor cells.
  
  
  METHODS
  Two human tumor cell lines (CX-2 colon adenocarcinoma, DAN-G pancreas adenocarcinoma) were exposed to a CO2 environment maintained at different pressures (0 mmHg, 6 mmHg, 12 mmHg). Tumor growth was determined at different times after exposure to CO2 using fluorescence photometry. Cytotoxity of the CO2 environment different pressures was investigated using flow cytometry.
  
  
  RESULTS
  At 1-4 days after exposure to CO2 insufflation, CX-2 and DAN-G tumor cell growth was decreased significantly (p < 0.01). Proliferation of pancreatic adenocarcinoma DAN-G increased significantly from day 5 to day 15 independent of the insufflation pressure (p < 0.01). Proliferation of colon adenocarcinoma CX-2 increased significantly from day 5 to day 15 but was found to be dependent on the insufflation pressure. CX-2 growth increased significantly with higher pressures (p < 0.05).
  
  
  CONCLUSIONS
  CO2 insufflation influences the growth of cultured human tumor cells. After a short period of suppression, the CO2 environment stimulates malignant cell growth. The insufflation pressure may also have additional effects in promoting tumor growth.
authors.affiliation: Department of General and Vascular Surgery, Johann Wolfgang Goethe University, Theodor Ster Kai 7, Frankfurt/Main, Germany. Gutt@em.uni-frankfurt.de
authors.forename: C N
authors.initials: CN
authors.lastname: Gutt
authors.forename: Z G
authors.initials: ZG
authors.lastname: Kim
authors.forename: D
authors.initials: D
authors.lastname: Hollander
authors.forename: T
authors.initials: T
authors.lastname: Bruttel
authors.forename: M
authors.initials: M
authors.lastname: Lorenz
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology*; D001274:Atmospheric Pressure; D002245:Carbon Dioxide / Q000008:administration & dosage / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects*; D003110:Colonic Neoplasms / Q000473:pathology; D004195:Disease Models, Animal; D005434:Flow Cytometry / Q000706:statistics & numerical data; D006801:Humans; D007327:Insufflation / Q000379:methods; D010190:Pancreatic Neoplasms / Q000473:pathology; D011028:Pneumoperitoneum, Artificial / Q000379:methods; D014407:Tumor Cells, Cultured / Q000187:drug effects
chemical_list: D002245:Carbon Dioxide