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MicroRNA-7 inhibits tumor metastasis and reverses epithelial-mesenchymal transition through AKT/ERK1/2 inactivation by targeting EGFR in epithelial ovarian cancer.

Zhou X, Hu Y, Dai L, Wang Y, Zhou J, Wang W, Di W, Qiu L - PLoS ONE (2014)

Bottom Line: Overexpression of miR-7 markedly suppressed the capacities of cell invasion and migration and resulted in morphological changes from a mesenchymal phenotype to an epithelial-like phenotype in EOC.The pharmacological inhibition of PI3K-AKT and ERK1/2 both significantly enhanced CK-18 and β-catenin expression and suppressed vimentin expression, indicating that AKT and ERK1/2 pathways are required for miR-7 mediating EMT.Taken together, our results suggested that miR-7 inhibited tumor metastasis and reversed EMT through AKT and ERK1/2 pathway inactivation by reducing EGFR expression in EOC cell lines.

View Article: PubMed Central - PubMed

Affiliation: Department of Gynecology and Obstetrics, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China; Shanghai Key Laboratory of Gynecologic Oncology, Shanghai, China.

ABSTRACT
Epidermal growth factor receptor (EGFR) overexpression and activation result in increased proliferation and migration of solid tumors including ovarian cancer. In recent years, mounting evidence indicates that EGFR is a direct and functional target of miR-7. In this study, we found that miR-7 expression was significantly downregulated in highly metastatic epithelial ovarian cancer (EOC) cell lines and metastatic tissues, whereas the expression of, EGFR correlated positively with metastasis in both EOC patients and cell lines. Overexpression of miR-7 markedly suppressed the capacities of cell invasion and migration and resulted in morphological changes from a mesenchymal phenotype to an epithelial-like phenotype in EOC. In addition, overexpression of miR-7 upregulated CK-18 and β-catenin expression and downregulated Vimentin expression, accompanied with EGFR inhibition and AKT/ERK1/2 inactivation. Similar to miR-7 transfection, silencing of EGFR with this siRNA in EOC cells also upregulated CK-18 and β-catenin expression and downregulated Vimentin expression, and decreased phosphorylation of both Akt and ERK1/2, confirming that EGFR is a target of miR-7 in reversing EMT. The pharmacological inhibition of PI3K-AKT and ERK1/2 both significantly enhanced CK-18 and β-catenin expression and suppressed vimentin expression, indicating that AKT and ERK1/2 pathways are required for miR-7 mediating EMT. Finally, the expression of miR-7 and EGFR in primary EOC with matched metastasis tissues was explored. It was showed that miR-7 is inversely correlated with EGFR. Taken together, our results suggested that miR-7 inhibited tumor metastasis and reversed EMT through AKT and ERK1/2 pathway inactivation by reducing EGFR expression in EOC cell lines. Thus, miR-7 might be a potential prognostic marker and therapeutic target for ovarian cancer metastasis intervention.

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Related in: MedlinePlus

miR-7 suppresses EOC cell invasion and migration in vitro.(A) Transwell migration and invasion assays using HO-8910pm cells transfected with miR-7 or negative control (NC). Representative images are shown on the left, and the quantification of 6 randomly selected fields is shown on the right. (B) Transwell migration and invasion assays using ES-2 cells transfected with miR-7 or NC. Representative images are shown on the left, and the quantification of 6 randomly selected fields is shown on the right. The values shown are expressed as the means ± SD. (*P<0.05.**P<0.01).
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pone-0096718-g003: miR-7 suppresses EOC cell invasion and migration in vitro.(A) Transwell migration and invasion assays using HO-8910pm cells transfected with miR-7 or negative control (NC). Representative images are shown on the left, and the quantification of 6 randomly selected fields is shown on the right. (B) Transwell migration and invasion assays using ES-2 cells transfected with miR-7 or NC. Representative images are shown on the left, and the quantification of 6 randomly selected fields is shown on the right. The values shown are expressed as the means ± SD. (*P<0.05.**P<0.01).

Mentions: To investigate whether miR-7 regulates cell invasion and migration in EOC, both HO-8910pm and ES-2 cells were transfected with miR-7 plasmid or miR-NC. Transwell migration and invasion assays were then performed. We found that transfection with miR-7 significantly suppressed the invasion of both HO-8910pm cells (Figure 3A) and ES-2 cells (Figure 3B). Similarly, migration capacity was also significantly down-regulated in both HO-8910pm-miR-7 cells and ES-2-miR-7 cells versus HO-8910pm-NC cells and ES-2-NC cells (Figure 3A, Figure 3B). These results indicate that miR-7 participates in the regulation of cell migration and invasion in EOC.


MicroRNA-7 inhibits tumor metastasis and reverses epithelial-mesenchymal transition through AKT/ERK1/2 inactivation by targeting EGFR in epithelial ovarian cancer.

Zhou X, Hu Y, Dai L, Wang Y, Zhou J, Wang W, Di W, Qiu L - PLoS ONE (2014)

miR-7 suppresses EOC cell invasion and migration in vitro.(A) Transwell migration and invasion assays using HO-8910pm cells transfected with miR-7 or negative control (NC). Representative images are shown on the left, and the quantification of 6 randomly selected fields is shown on the right. (B) Transwell migration and invasion assays using ES-2 cells transfected with miR-7 or NC. Representative images are shown on the left, and the quantification of 6 randomly selected fields is shown on the right. The values shown are expressed as the means ± SD. (*P<0.05.**P<0.01).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4016102&req=5

pone-0096718-g003: miR-7 suppresses EOC cell invasion and migration in vitro.(A) Transwell migration and invasion assays using HO-8910pm cells transfected with miR-7 or negative control (NC). Representative images are shown on the left, and the quantification of 6 randomly selected fields is shown on the right. (B) Transwell migration and invasion assays using ES-2 cells transfected with miR-7 or NC. Representative images are shown on the left, and the quantification of 6 randomly selected fields is shown on the right. The values shown are expressed as the means ± SD. (*P<0.05.**P<0.01).
Mentions: To investigate whether miR-7 regulates cell invasion and migration in EOC, both HO-8910pm and ES-2 cells were transfected with miR-7 plasmid or miR-NC. Transwell migration and invasion assays were then performed. We found that transfection with miR-7 significantly suppressed the invasion of both HO-8910pm cells (Figure 3A) and ES-2 cells (Figure 3B). Similarly, migration capacity was also significantly down-regulated in both HO-8910pm-miR-7 cells and ES-2-miR-7 cells versus HO-8910pm-NC cells and ES-2-NC cells (Figure 3A, Figure 3B). These results indicate that miR-7 participates in the regulation of cell migration and invasion in EOC.

Bottom Line: Overexpression of miR-7 markedly suppressed the capacities of cell invasion and migration and resulted in morphological changes from a mesenchymal phenotype to an epithelial-like phenotype in EOC.The pharmacological inhibition of PI3K-AKT and ERK1/2 both significantly enhanced CK-18 and β-catenin expression and suppressed vimentin expression, indicating that AKT and ERK1/2 pathways are required for miR-7 mediating EMT.Taken together, our results suggested that miR-7 inhibited tumor metastasis and reversed EMT through AKT and ERK1/2 pathway inactivation by reducing EGFR expression in EOC cell lines.

View Article: PubMed Central - PubMed

Affiliation: Department of Gynecology and Obstetrics, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China; Shanghai Key Laboratory of Gynecologic Oncology, Shanghai, China.

ABSTRACT
Epidermal growth factor receptor (EGFR) overexpression and activation result in increased proliferation and migration of solid tumors including ovarian cancer. In recent years, mounting evidence indicates that EGFR is a direct and functional target of miR-7. In this study, we found that miR-7 expression was significantly downregulated in highly metastatic epithelial ovarian cancer (EOC) cell lines and metastatic tissues, whereas the expression of, EGFR correlated positively with metastasis in both EOC patients and cell lines. Overexpression of miR-7 markedly suppressed the capacities of cell invasion and migration and resulted in morphological changes from a mesenchymal phenotype to an epithelial-like phenotype in EOC. In addition, overexpression of miR-7 upregulated CK-18 and β-catenin expression and downregulated Vimentin expression, accompanied with EGFR inhibition and AKT/ERK1/2 inactivation. Similar to miR-7 transfection, silencing of EGFR with this siRNA in EOC cells also upregulated CK-18 and β-catenin expression and downregulated Vimentin expression, and decreased phosphorylation of both Akt and ERK1/2, confirming that EGFR is a target of miR-7 in reversing EMT. The pharmacological inhibition of PI3K-AKT and ERK1/2 both significantly enhanced CK-18 and β-catenin expression and suppressed vimentin expression, indicating that AKT and ERK1/2 pathways are required for miR-7 mediating EMT. Finally, the expression of miR-7 and EGFR in primary EOC with matched metastasis tissues was explored. It was showed that miR-7 is inversely correlated with EGFR. Taken together, our results suggested that miR-7 inhibited tumor metastasis and reversed EMT through AKT and ERK1/2 pathway inactivation by reducing EGFR expression in EOC cell lines. Thus, miR-7 might be a potential prognostic marker and therapeutic target for ovarian cancer metastasis intervention.

Show MeSH
Related in: MedlinePlus