Objective: To explore the effects of exogenous suppressor of cytokine signaling 3 (SOCS3) in Janus Kinase/Signal transducer and activator of transcription 3 (JAK2/STAT3) signaling pathways and examine the relationship between exogenous SOCS3 and cell proliferation and apoptosis in ectopic endometrial stromal cells.
Methods: Ectopic endometrial stromal cells from patients with histopathologically confirmed endometriosis were primarily cultured in vitro. Vimentin staining was used to identify the purity of endometrial stromal cells. Lentivirus containing SOCS3 and GFP (green fluorescent protein) recombinant (LV-SOCS3-GFP) or only GFP gene (LV-GFP) was used to transfect two groups of ectopic endometrial stromal cells from the same patient respectively. They were divided into experimental (EG) and negative (NC) control. The transfection efficiency of lentivirus was measured by GFP fluorescence expression under microscope. And the expressions of SOCS3, STAT3 and JAK2 mRNA and protein were analyzed by real-time polymerase chain reaction (PCR) and Western blot respectively. And phosphorylated JAK2 and STAT3 proteins (p-STAT3 and p-JAK2) were also analyzed by Western blot. Cell cycles and apoptosis were detected by flow cytometry.
Results: The transfection efficiency of lentivirus was over 80% at 72 h post-transfection. Compared with NC, EG showed a higher expression of SOCS3 mRNA (P < 0.001). SOCS3 protein level of EG was higher than NC while p-STAT3 protein of EG obviously lower than NC. STAT3, JAK2 and p-JAK2 proteins showed no difference between two groups. The percentage of apoptotic cells in EG was higher remarkably than NC (22.0 ± 1.3)% vs (4.4 ± 1.3)%, P < 0.01. Moreover, EG cells showed a G0/G1 arrest compared with NC (87.0 ± 3.7)% vs (76.0 ± 3.7)%, P < 0.05.
Conclusion: Exogenous SOCS3 induces cell apoptosis and inhibits cell proliferation in ectopic endometrial stromal cells.