Influence of CO2 pneumoperitoneum on intracellular pH and signal transduction in cancer cells.
OBJECTIVE
The authors studied the influence of CO(2) pneumoperitoneum on intracellular pH and signal transduction arising from cancer cell multiplication in laparoscopic tumor operation.


METHODS
They set up a simulation of pneumoperitoneum under different CO(2) pressure, and then measured the variation of intracellular pH (pHi) at different time and the activity of protein kinase C (PKC) and protein phosphatase 2a (PP2a) at the end of the pneumoperitoneum. After 1 week, the concentration of cancer cells in the culture medium was calculated.


RESULTS
When the pressure of CO(2) pneumoperitoneum was 0, 10, 20, 30 mmHg respectively, the average pHi was 7.273, 7.075, 6.783, 6.693 at the end of the pneumoperitoneum; PKC activity was 159.4, 168.5, 178.0, 181.6 nmol/(g.min) and PP2a was 4158.3, 4066.9, 3984.0, 3878.5 nmol/(g.min) respectively. After 1 week, the cancer cells concentration was 2.15 x 10(5), 2.03 x 10(5), 2.20 x 10(5), 2.18 x 10(5) L(-1).


CONCLUSIONS
CO(2) pneumoperitoneum could promote acidosis in cancer cells, inducing the activation of protein kinase C and deactivation of protein phosphatase 2a, but it could not accelerate the mitosis rate of the cancer cells.
Department of Surgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China. cao@zju.edu.cn
Li-Ping
LP
Cao
Guo-Ping
GP
Ding
Ri-Sheng
RS
Que
Shu
S
Zheng
D000818:Animals; D001943:Breast Neoplasms / Q000737:chemistry* / Q000378:metabolism*; D002245:Carbon Dioxide / Q000008:administration & dosage*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004789:Enzyme Activation / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D007424:Intracellular Fluid / Q000737:chemistry; D010749:Phosphoprotein Phosphatases / Q000378:metabolism*; D011028:Pneumoperitoneum, Artificial / Q000379:methods*; D011493:Protein Kinase C / Q000378:metabolism*; D054648:Protein Phosphatase 2; D051381:Rats; D015398:Signal Transduction / Q000187:drug effects*
D002245:Carbon Dioxide; D011493:Protein Kinase C; D010749:Phosphoprotein Phosphatases; D054648:Protein Phosphatase 2