OBJECTIVETo study the effect of different CO2 pneumoperitoneum pressures on the expression of adhesion molecules of human gastric cancer cell line MNK-45.

METHODSMKN-45 cells in the experimental groups were exposed to simulated CO2 environment maintained at different pressures (1.2, 1.6, 2.0 kPa) for 4 hours. Control groups were exposed to room air. At the 0, 24, 48, 72, 96 hours after treatment, CD44v6, ICAM-1 and E-cadherin were detected by flow cytometry method.

RESULTSCD44v6 and ICAM-1 expressions showed pattern of firstly elevating, then descending to normal under the pressures of 1.2 kPa and 1.6 kPa. The expressions were different from control group significantly at 24 and 48 hours (P<0.01), while the 72 hours expression showed no difference compared with the controls (P>0.05). E-cadherin expression decreased significantly right after treatment compared to the control (P<0.01), but recovered to the level of control at 48 hours (P>0.05). In the 2.0 kPa group the expression changes of CD44v6, ICAM-1 and E-cadherin were more remarkable. CD44v6 and ICAM-1 expressions were increased significantly compared to control right after treatment (P<0.05). E-cadherin expression was significantly decreased even at 48 hours compared to the controls (P<0.01).

CONCLUSIONIn vitro CO2 pneumoperitoneum pressures have transient influence on the adhesion molecules expression of gastric cancer cell MKN-45, then those expressions can recover in a short-time.