Published online Jun 14, 2020. doi: 10.3748/wjg.v26.i22.3034
Peer-review started: February 11, 2020
First decision: March 26, 2020
Revised: April 10, 2020
Accepted: April 24, 2020
Article in press: April 24, 2020
Published online: June 14, 2020
CircRNAs are considered valuable diagnostic biomarkers for Crohn's disease (CD). Our previous study demonstrated that hsa_circRNA_102610 was upregulated in CD patients. Furthermore, miRNA response element (MRE) analysis suggested the existence of a potential interaction between hsa_circRNA_102610 and hsa-miR-130a-3p. Current evidence supports the views that epithelial-mesenchymal transition (EMT) plays an important role in CD pathogenesis, and that hsa-miR-130a-3p can inhibit transforming growth factor-β1 (TGF-β1)-induced EMT.
Further investigation is required to explore the mechanism of hsa_circRNA_102610 in the pathogenesis of CD.
This study was designed to investigate whether the upregulation of hsa_circRNA_102610 correlates with the degree of inflammation in Crohn's disease. The CALP level, C-reactive protein (CRP) level and erythrocyte sedimentation rate (ESR) were included in the correlation analysis. Furthermore, the roles that hsa_circRNA_102610 may play in the proliferation and EMT of intestinal epithelial cells were studied in normal-derived colon mucosa cell line 460 (NCM460) and human intestinal epithelial cells (HIECs).
The relative expression levels of hsa_circRNA_102610 and hsa-miR-130a-3p in CD patients were detected by quantitative reverse transcription-polymerase chain reaction. The proliferation of HIECs and NCM460 cells was detected by cell counting kit-8, EdU staining and cell cycle assays following overexpression or downregulation of hsa_circRNA_102610. Cell proliferation assays were performed as described above in a rescue experiment with hsa-miR-130a-3p mimics. The interaction of hsa_circRNA_102610 and hsa-miR-130a-3p was verified by fluorescence in situ hybridization and dual luciferase reporter assays. The relative expression levels of CyclinD1, SMAD4, E-cadherin, N-cadherin and Vimentin were detected by western blotting following hsa_circRNA_102610 overexpression, TGF-β1-induced EMT or hsa-miR-130a-3p mimic transfection (in rescue experiments).
Upregulation of hsa_circRNA_102610 was determined to be positively correlated with elevated fecal calprotectin levels in CD (r = 0.359, P = 0.007) by Pearson correlation analysis. Hsa_circRNA_102610 promoted the proliferation of HIECs and NCM460 cells, while hsa-miR-130a-3p reversed the cell proliferation-promoting effects of hsa-circRNA_102610. Fluorescence in situ hybridization and dual luciferase reporter assays showed that hsa_circRNA_102610 directly bound hsa-miR-130a-3p in NCM460 and 293T cells. An inverse correlation between downregulation of hsa-miR-130a-3p and upregulation of hsa_circRNA_102610 in CD patients was observed (r = -0.290, P = 0.024) by Pearson correlation analysis. Moreover, overexpression of hsa_circRNA_102610 promoted SMAD4 and CyclinD1 protein expression, as validated by western blotting. Furthermore, overexpression of hsa_circRNA_102610 promoted TGF-β1-induced EMT in HIECs and NCM460 cells via targeting of hsa-miR-130a-3p, with increased expression of Vimentin and N-cadherin and decreased expression of E-cadherin.
Hsa_circRNA_102610 upregulation in CD patients could promote the proliferation and EMT of intestinal epithelial cells via sponging of hsa-miR-130a-3p.
Hsa_circRNA_102610 may serve as a potential target for CD therapy and novel drug research. Externally delivered hsa-miR-130a-3p could possibly act as a sponge of hsa_circRNA_102610.