Effect Of The Implantation Metastasis After The Different CO₂Pneumoperitoneum Conditions For Ovarian Cancer On The Nude Mice And Its Mechanism

Objective: To simulate the different conditions of CO₂pneumoperitoneum in vitroenvironment and then to study the effects of the growth and proliferation of ovarian cancerSKOV₃cell after CO₂pneumoperitoneum, and then to preliminary assess the safety oflaparoscopic surgery about ovarian cancer in vivo.Methods:1. To simulate the different conditions of CO₂pneumoperitoneum in vitroenvironment. The experiment was divided into five groups: the blank control group, thelaparotomy control group, the constant3mmHg pneumoperitoneum groups, the constant8mmHg pneumoperitoneum group, and the pulse8mmHg pneumoperitoneum group. Theintervention of each group lasted two hours.2．To find the growing and proliferative effect of ovarian cancer cell in vitro afterdifferent conditions of CO₂pneumoperitoneum by the Cell Counting Kit-8(CCK-8) kitassay.3．To find the effect about the expression of the mRNA gene VEGF-C, CD44v6andE-cadherin of ovarian cancer cell in vitro after different conditions of CO₂pneumoperitoneum by the Real Time-PCR assay.Results:1．Both the CO₂pneumoperitoneum and laparotomy environment can inhibit thegrowth and proliferation of human ovarian cancer SKOV₃cell in vitro. And with thepressure increasing, the inhibitory effect is more obvious. The low pressure (3mmHg)pneumoperitoneum group has the smaller effect than the laparotomy group on the growthand proliferation, but there were not statistically significant (P>0.05). There were not statistically significant about the growth and proliferation of ovarian cancer SKOV₃cell invitro after CO₂pneumoperitoneum between in two types pneumoperitoneum machine (P>0.05).2．Both the CO₂pneumoperitoneum and laparotomy environment can inhibit theexpression of the mRNA gene VEGF-C, CD44v6and E-cadherin of the human ovariancancer SKOV₃cell in vitro. And with the pressure increasing, the inhibitory effect is moreobvious. The low pressure (3mmHg) pneumoperitoneum group has the smaller effect thanthe laparotomy group, but there were not statistically significant (P>0.05).There wasstatistically significant about the inhibitory expression of the mRNA gene VEGF-C,CD44v6and E-cadherin of ovarian cancer SKOV₃cell in vitro after pulsepneumoperitoneum machine than constant pneumoperitoneum machine (P>0.05).Conclusion: CO₂pneumoperitoneum has no promoted effect about the growth andproliferation of ovarian cancer cell in vitro and it can be used for in vivo studies. Objective: To construct the nude mice model of ovarian cancer with the humanovarian cancer cells. To intervene the nude mice with different conditions of laparoscopicCO₂pneumoperitoneum, and then to study the effects of the prognosis of ovarian cancernude mice model after different conditions of laparoscopic CO₂pneumoperitoneum.Method:1．To construct the nude mice ovarian cancer model by intraperitoneal injection withstable passaged human SKOV₃cell. 2．To study the species specificity of the ovarian cancer in nude mice model by theReal Time-PCR assay.3．The thirty nude mice were randomly divided into five groups: the blank controlgroup, the laparotomy control group, the constant3mmHg pneumoperitoneum groups, theconstant8mmHg pneumoperitoneum group, and the pulse8mmHg pneumoperitoneumgroup (n=6). The intervention of each group lasted one hour. And the control groupintervened without pneumoperitoneum. Those mice continued breeding in theSpecific-pathogen-free (SPF) laboratory until their death after that intervention.Results:1．The model of ovarian cancer in nude mice was successful, and the characteristics ofthe model had both that of solid tumor and ascites tumor.2．The solid tumors and the ascites tumor in nude mice were murine tumor.3．Laparotomy group and different conditions of the CO₂pneumoperitoneum groupwere bad influence on the prognosis of ovarian cancer. And with the pressure increasing,the detrimental effect is more obvious. However, no significant difference between thelaparotomy and low pressure (3mmHg) pneumoperitoneum group. In case of the highpneumoperitoneum pressure group(8mmHg), the pulse pneumoperitoneum machine hadthe more detrimental effect than the constant one in the prognosis of ovarian cancer.Conclusion: Laparotomy (only switch surgery, without cytoreductive operation) andCO₂pneumoperitoneum were bad influence on the prognosis of ovarian cancer. And withthe pressure increasing, the detrimental effect is more obvious. However, there was nosignificant difference between the laparotomy and low pressure (3mmHg)pneumoperitoneum group. In case of the high pneumoperitoneum pressure group(8mmHg),the pulse pneumoperitoneum machine had the more detrimental effect than the constantone in the prognosis of ovarian cancer. Objective: To build animal model of ovarian cancer in nude mice and to intervene thatmodel with different conditions of CO₂pneumoperitoneum. To study the expression of themRNA of the gene VEGF-C and CD44v6, E-cadherin after pneumoperitoneum in ovariancancer nude mice by the Real Time-PCR assay and ELISA. To study the ultrastructurechange of peritoneal local after CO₂pneumoperitoneum by the microscopy electronmicroscopy. To further study the mechanism of the prognosis of laparoscopic CO₂pneumoperitoneum conditions in ovarian cancer comparing to the laparotomy group.Method:1．To find the effect about the expression of the mRNA gene VEGF-C, CD44v6andE-cadherin of ovarian cancer cell in nude mice after different conditions of CO₂pneumoperitoneum by the Real Time-PCR assay.2．To find the change of the protein of gene VEGF-C, CD44v6and E-cadherin beforethe intervention and7days after intervention by the ELISA.3．To observe the ultrastructure change of the peritoneal of the nude mice after thedifferent conditions of CO₂pneumoperitoneum by the transmission electron microscopy.Results:1．The expression of the protein of VEGF-C and CD44v6raised, but there was notstatistically significant between in each group (P>0.05). The expression of the protein ofE-cad decreased, but there was not statistically significant between in each group (P>0.05).2．There was not statistically significant in the expression of the protein of VEGF-C,CD44v6and E-cadherin among in laparotomy and CO₂pneumoperitoneum groupscompared with the control group (P>0.05).3．There was irreversible damage in the peritoneal mesothelial cells after CO₂ pneumoperitoneum. The damage was more serious with the pressure increasing. The mostserious damage was observed in the pulse pneumoperitoneum group, which endothelialcells was incomplete, collapse of the fracture was more common, the cell gap was huge,and the microvillus was fracture. Every layers can be seen a large number of tumor cell.Conclusion: Compared with traditional laparotomy, there was no evidence that theCO₂pneumoperitoneum surgery change the biological characteristics of ovarian cancer.However, high CO₂pneumoperitoneum pressure may damage the peritoneal mesothelialcells and basal cells, and reduce the defense ability of peritoneum.