Expression Change And Effect On Malignant Biological Behavior Of MiR-99 Family During TGF-?1 Medicated Epithelial-mesenchymal Transition

Objective To explore the expression level change and its effect on malignant biological behavior of miR-99 family during TGF-?1 medicated epithelial-mesenchymal transition in ovarian cancer cells.To investigate the feasibility of miR-99 as an index of malignancy and target of therapy in ovarian cancer.Methods Ovarian cancer cell line A2780 and SKOV3 were treated with TGF-?1 in dose gradient and time gradient.Real-time q RT-PCR was used to detect the expression level change of miR-99 family,Western-blot was employed to examine the expression level change of epithelial marker E-cadherin and mesenchymal marker Vimentin,CCK-8 test was applied to determine the proliferation,Wound-Healing and Transwell were utilized to test the migration and invasion.Analyze the association of miR-99 expression level and epithelial-mesenchymal transition with malignant biological behavior of ovarian cancer.Then we transfect ovarian cancer cell line with miRNA mimic of inhibitor of miR-99 family to investigate whether or not it could inhibit the promotion effect on malignant biological behavior of TGF-?1.Results After ovarian cell line A2780 and SKOV3 were treated with TGF-?1: ?compated with the blank control group,the proliferation was enhanced in time-/dose-dependent manner,even the minimum dose group 2 ng/m L and minimum time group 12 h have statistical significant difference(P<0.01);?compared with the blank control group,the expression level of miR-99 family members was elevated with statistical significant difference(P<0.01);?compared with the blank control group,epithelial marker E-cadherin was increased while mesenchymal marker Vimentin was decreased;?compared with the blank control group,both migration and invasion were strengthened with statistical significant difference(P<0.05).After ovarian cell line A2780 and SKOV3 were transfected with miR-99 family mimic/inhibitor respectively or combinedly: ?compared with the blank or negative control group,proliferation of ovarian cancer cells was enhanced after being transfected with inhibitor of miR-99 family members respectively,the enhance of combined transfection group was stronger than respective group.All the difference is statistically significant(P<0.05);?compared with the blank or negative control group,proliferation of ovarian cancer cells was weakened after being transfected with mimic of miR-99 family members respectively,the inhibition effect of combined transfection group was stronger than respective group.All the difference is statistically significant(P<0.05);?compared with the TGF-?1 treated group,miRNA mimic of miR-99 family was not able to resist the proliferation enhancement of TGF-?1 when transfected to the TGF-?1 treated ovarian cancer cells,but could make a statistical significant difference when transfected combinedly(P<0.05);?compared with the blank or negative control group,miR-99 family mimic transfection could strengthen the migration of ovarian cancer cells while miR-99 family inhibitor transfection could weaken it,and the difference is statistically significant(P<0.05);?compared with the TGF-?1 treated group,miRNA inhibitor of miR-99 family combined transfection could resist the migration enhancement of TGF-?1 in ovarian cancer cells with statistical significant difference(P<0.05);?compared with the blank or negative control group,miR-99 family mimic transfection could strengthen the invasion of ovarian cancer cells while miR-99 family inhibitor transfection could weaken it,and the difference is statistically significant(P<0.05);?compared with the TGF-?1 treated group,miRNA inhibitor of miR-99 family combined transfection could partly resist the migration enhancement of TGF-?1 in ovarian cancer cells,but has no statistically significant difference(P<0.05).Conclusion The expression level of miR-99 family was increased in the process of TGF-?1-medicated epithelial-mesenchymal transition with enhancement of malignant biological behavior in ovarian cancer cell lines,suggesting that the expression level of miR-99 family could be used as an indicator in judging the grade of malignance of ovarian cancer.Transfection of miR-99 family mimic/inhibitor could resist the promotion effect of TGF-?1 in proliferation and migration,indicating that miR-99 family may serve as one of the potential targets in ovarian cancer therapy.