Circ-104792/miR-133a/Bcl-xL influences the proliferation and function of human trophoblastic and decidual stromal cells involved in recurrent abortion disease
Wenjuan Ma1, Yuan Ma2, Hongli Zhu3
1Department of Obstetrics and Gynecology, Xi'an People's Hospital (Xi'an Fourth Hospital), Xi'an, Shaanxi, China.
Background:
The circRNA-miRNA axis is critically implicated in the pathogenesis of recurrent spontaneous abortion (RSA) by modulating trophoblast and decidual stromal cell functions. This study investigates the role of the miR-133a/circ-104792 network in RSA.
Methods:
Using qRT-PCR, we measured miR-133a and circ-104792 expression in chorion and decidua from 10 RSA patients and 10 controls. The functional effects on proliferation (CCK-8, EdU) and apoptosis (flow cytometry, TUNEL) were assessed in HTR-8/SVneo and HESC cells following transfection with miR-133a mimics/inhibitor or circ-104792. Direct targeting of Bcl-xL by miR-133a and its interaction with circ-104792 were validated via dual-luciferase reporter and RNA pull-down assays. Bcl-xL expression was evaluated by qRT-PCR and western blot.
Results:
miR-133a expression was (in chorion: p = 0.0008, 95% CI [2.85, 6.41]; in decidua: p = 0.0009, 95% CI [2.67, 6.03]) increased, while circ-104792 was significantly downregulated (in chorion: p = 0.0008, 95% CI [0.15, 0.34]; in decidua: p = 0.0007, 95% CI [0.13, 0.31]) in RSA tissues. In vitro, miR-133a overexpression inhibited cell proliferation, promoted apoptosis, and reduced Bcl-xL levels (in HTR-8/SVneo: 0.46-fold vs. 1.00 in NC group, p = 0.0045; in HESCs: 0.49-fold vs. 1.00 in NC group, p = 0.0003). Conversely, circ-104792 overexpression enhanced proliferation, suppressed apoptosis, and increased Bcl-xL expression (in HTR-8/SVneo: 2.17-fold vs. 1.00 in vector group, p = 0.0018; in HESCs: 1.94-fold vs. 1.00 in vector group, p = 0.0015). The dual-luciferase assay confirmed Bcl-xL as a direct target of miR-133a, and the RNA pull-down confirmed the miR-133a/circ-104792 interaction. Critically, circ-104792 overexpression rescued the suppressive effects of miR-133a on proliferation and Bcl-xL expression.
Conclusion:
Our findings demonstrate that miR-133a promotes RSA-associated cellular dysfunction by targeting Bcl-xL, while circ-104792 acts as a ceRNA to sponge miR-133a, thereby antagonizing its effects. The miR-133a/circ-104792/Bcl-xL axis represents a potential key regulatory network in RSA, presenting potential novel targets for diagnosis and therapy.
