Expression Of PTEN And P-Akt In Human Uterine Leiomyoma And Effect Of EGCG On The Uterine Leiomyoma Cells In Vitro

Objective:To investigate the expression of PTEN and p-Akt in human uterine leiomyoma and in myometrium which relates to the development of uterine leiomyoma,and the suppressive effect of EGCG on the proliferation and apoptosis of human uterine leiomyoma cells in vitro and on the expression of PTEN and p-Akt. Our purpose was to investigate the pathogenesis of uterine leiomyoma and the effects of EGCG on the growth of human uterine leiomyoma cell line in vitro and its mechanism of action.Methods:The expression of PTEN and p-Akt were determined by immuno-chemical SP method on uterine leiomyoma and myometrium in 30 patients.Uterine leiomyoma cells were cultured in vitro, after the action of EGCG with different concentration, MTT was used to examine the proliferative activity of uterine leiomyoma cells,the distribution of cell cycle and the rate of apoptosis were determined by flow cytometry. The expression of p-Akt and PTEN protein was detected by immunocytochemistry.Results:1.PTEN level in uterine leiomyoma was lower than that in myometrium. P-Akt level in uterine leiomyoma was higher than that in myometrium.They are negative correlated in uterine leiomyoma.2.Human uterine leiomyoma cells were successfully cultivated in vitro and identified by immunocyto chemistry .3.All groups uterine leiomyoma cells grow well. EGCG inhibited leiomyoma cell proliferation in a dose and time-dependent manner. After 24h the proliferative activity of cells were inhibited (P<0.05), 48h the inhibitory effect increased steadily (P<0.05), 72h at the most significant inhibitory effect (P<0.01).With the dose increased, the suppressive effect of EGCG was gradually enhanced (P<0.05).4. The rate of cell apoptosis were increased by EGCG in a dose-dependent manner, with the dose increased,the rate of G1 cell phase were increased and the rate of S cell phase were declined,the difference was significant (P<0.05). 5.Treated with EGCG of 2×10^-4mol/L for 72h,the experission of p-Akt in human uterine leiomyoma cells was significantly down-regulated(P<0.01), as well as the experission of PTEN was up-regulated(P<0.05).Conclusion:1.The down-regulation of PTEN could overactived Akt pathway,which plays an important role in the development of human uterine leiomyoma.2. EGCG could inhibit the proliferation of uterine leiomyoma cells in vitro as direct relation of concentrations and times and enhance the apoptosis rate in the dosage-dependent.3. EGCG could up-regulate the expression of PTEN protein and down-regulate the expression of p-Akt protein,which leads to the inhibition of cells proliferation and its apoptosis.