Abstract: Objective To investigate the effect of CO₂-insufflation on expression of CDK9 mRNA of cervical cancer cell line Hela, and to analyze the role of CO₂ in growth and metastasis of Hela. Methods Hela cells were randomly divided into two study groups (A and B) and one control group (C). The cells in group A were exposed to CO₂ with 8 mmHg and incubated for 24 hours,the cells in group B were exposed to CO₂ with 8 mmHg and incubated for 120 hours, the cells in group C were not exposed to CO_2.Real-time PCR was used to detect the expression of CDK9 mRNA of Hela cells collected from each group.ResultsT he expression of CDK9 mRNA of Hela cells in the two study groups was lower than that in control group (P＜0.05),and the expression of CDK9 mRNA of Hela cells in group B was lower than that in group A (P＜0.01)Conclusions The expression of CDK9 mRNA can be down-regulated by CO₂-insufflation.The expression of CDK9 mRNA decreased more obvious with longer incubation time

Key words: RT-PCR;, CDK9, Cervical cancer cells, Gene expression