38. Influence of different CO₂ pneumoperitoneum pressures on the expression of adhesion molecules on gastric cancer cells

Objective: To study the effect of different carbon dioxide pneumoperitoneum pressures on the expression of adhesion molecules on human gastric cancer cells line MNK-45.
Methods: MKN-45 in experimental groups were exposed to simulated CO₂ environment maintained at different pressures (9, 12, 15 mmHg) 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.
Results: CD44V6 and ICAM-1 expressions show pattern of elevating and descending to normal under the pressures of 9 mmHg and 12 mmHg. 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 control. E-cadherin expression decreased 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 15 mmHg group the 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 decreased even at 48 hours compared to control (P<0.01) but show no significant difference at 72 hours.
Conclussions: In vitro simulated pneumoperitoneum pressures which were usually applied in clinical practices have transient influences on the adhesion molecular expression on gastric cancer cell MKN-45.