Study On The Expression And Function Of MiRNA-144in The Chorionic Villi Of Recurrent Spontaneous Abortion

Objective:1. To investigate the differential expression of miR-144in the chorionic villi of recurrent spontaneous abortion and normal early pregnancy.2. To investigate the regulatory effect of miR-144on its target gene STAT1in human trophoblast cells HTR-8.3. To understand the effect of miR-144on apoptosis of human trophoblast cells HTR-8, in order to explore the role of miR-144in the development process of recurrent spontaneous abortion.Methods:1. Using real-time PCR to investigate the expression of miR-144in the chorionic villi of15cases of normal early pregnancy and15cases of recurrent spontaneous abortion.2. Using transient transfection technology to transfect miR-144mimics and miR-144inhibitor into human normal trophoblast cell line (HTR-8) to increase and decrease the expression of miR-144, then investigate the expression of miR-144and STAT1mRNA in HTR-8cells through the RT-PCR technology, and using western-blot technology to detect the expression of STAT1protein.3. To detect HTR-8cell apoptosis changes by using flow cytometry after over-expressing and inhibiting the expression of miR-144in HTR-8cell.Results:1.Real-time PCR results showed that, the expression of miR-144in the chorionic villi of recurrent spontaneous abortion was lower than control group (P<0.001).2. After over-expressing and inhibiting the expression of miR-144in HTR-8cell, the results of RT-PCR showed that the expression of miR-144in the over-expression group was higher than the normal group, while the expression of STAT1mRNA in the over-expression group was lower than the normal group, the differences were statistically significant (P<0.001); and the expression of miR-144in the inhibition group was lower than the normal group, while the expression of STAT1mRNA in the inhibition group was higher than the normal group, the differences were statistically significant (P<0.001); the results of western-blot showed that the expression of STAT1protein in the over-expression group was lower than the normal group, while the expression of STAT1protein in the inhibition group was higher than the normal group, the differences were statistically significant (P<0.05). These suggest that the expression of STAT1at the mRNA and protein levels are negatively regulated by miR-144.3. After over-expressing and inhibiting the expression of miR-144in HTR-8cell, the flow cytometry results showed that the cells apoptosis rate was lower than control group after up regulated the expression of miR-144, the difference was statistically significant (P<0.05); while the cells apoptosis rate was higher than control group after down regulated the expression of miR-144, and the difference was statistically significant (P<0.001).Conclusion:1.The expression of miR-144is decreased in the chorionic villi of recurrent spontaneous abortion, suggesting the miR-144may lead to the occurrence of the recurrent spontaneous abortion.2. STAT1is a target role of miR-144, and miR-144has a negative regulatory effect on STAT1at the mRNA and protein levels.3. MiR-144can inhibit the apoptosis of trophoblastic cells, suggesting miR-144which is low expression in the chorionic villi of recurrent spontaneous abortion possibly participated in the pathogenesis of recurrent spontaneous abortion through increasing apoptosis of trophoblast cells.