LncRNA-TCL6 promotes early abortion and inhibits placenta implantation via the EGFR pathway.

OBJECTIVE: The aim of this study was to investigate the role of long non-coding RNA (lncRNA) TCL6 in early abortion and to explore its underlying mechanism.

PATIENTS AND METHODS: The expression levels of lncRNA-TCL6 and epidermal growth factor receptor (EGFR) in placental tissues of normal pregnancy, threatened abortion pregnancy, spontaneous abortion pregnancy, and induced abortion pregnancy were detected by quantitative Real-Time Polymerase Chain Reaction (qRT-PCR), respectively. Trophoblast cells were transfected with siRNA to knock-down lncRNA-TCL6. Cell viability of trophoblast cells was detected by cell counting kit-8 (CCK-8) assay. The protein expression levels of EGFR, extracellular regulated protein kinases (ERK) and protein kinase B (AKT) in trophoblast cells after lncRNA-TCL6 knockdown were detected by Western blot. Rescue experiments were performed to investigate the relationship between EGFR and lncRNA-TCL6.

RESULTS: The expression of lncRNA-TCL6 in placenta tissues of threatened abortion pregnancy was significantly higher than that of normal pregnancy. Meanwhile, the expression of lncRNA-TCL6 in placenta tissues of spontaneous abortion pregnancy was also markedly higher than induced abortion pregnancy. However, the expression of EGFR showed an opposite trend. After knockdown of lncRNA-TCL6 in trophoblast cells, the protein expression levels of EGFR, ERK, and AKT were significantly increased when compared with those of the control group. CCK-8 assay indicated that cell viability was remarkably increased after knockdown of lncRNA-TCL6, which could be reversed by EGFR knockdown.

CONCLUSIONS: Compared with normal pregnancy, lncRNA-TCL6 was highly expressed in placental tissues of threatened abortion pregnancy. Moreover, the expression of lncRNA-TCL6 in placenta tissues of spontaneous abortion pregnancy was significantly higher than induced abortion pregnancy. Knockdown of lncRNA-TCL6 promoted the proliferation of trophoblast cells and inhibited the abortion via the EGFR signaling pathway.