MiRNA-221-5p promotes breast cancer progression by regulating E-cadherin expression

• Published in: European review for medical and pharmacological sciences Vol. 23; no. 16; p. 6983
• Main Authors: Niu, X-Y, Zhang, Z-Q, Ma, P-L
• Format: Journal Article
• Language: English
• Published: Italy 01.08.2019
• Subjects: Aged; Breast Neoplasms - metabolism; Breast Neoplasms - pathology; Cadherins - genetics; Cadherins - metabolism; Cell Proliferation; Female; Humans; MCF-7 Cells; MicroRNAs - genetics; MicroRNAs - metabolism; Middle Aged; Tumor Cells, Cultured
• ISSN: 2284-0729
• DOI: 10.26355/eurrev_201908_18738

To elucidate the role of miRNA-221-5p in the development of breast cancer (BCa) and its underlying mechanism. The expression level of miRNA-221-5p in 52 pairs of BCa tissues and adjacent normal tissues was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The correlation between miRNA-221-5p expression and pathological indicators of BCa was analyzed. MiRNA-221-5p expression in BCa cells was also determined by qRT-PCR. After transfection of miRNA-221-5p inhibitor in MCF-7 and SKBR3 cells, we detected the regulatory effects of miRNA-221-5p on cellular behaviors through cell counting kit-8 (CCK-8), wound healing, and transwell assay. Finally, the relationship between miRNA-221-5p and E-cadherin in BCa was elucidated. QRT-PCR results showed that the expression level of miRNA-221-5p in BCa tissues was markedly higher than that in normal tissues. Compared with BCa patients with low expression of miRNA-221-5p, those with high expression had a higher incidence of lymph node metastasis and distant metastasis. However, miRNA-221-5p expression did not correlate with age and sex of BCa patients. MiRNA-221-5p was also highly expressed in BCa cells. Transfection of miRNA-221-5p inhibitor suppressed proliferative, invasive, and migratory potentials of BCa cells. Subsequently, we verified that E-cadherin was lowly expressed in BCa cells, and negatively correlated with miRNA-221-5p. In addition, rescue experiments confirmed that transfection of si-E-cadherin reversed the inhibitory role of miRNA-221-5p knockdown in migratory and invasive potentials of BCa cells. The expression of miRNA-221-5p remained high in BCa, which was correlated with lymph node metastasis, distant metastasis, and poor prognosis of BCa. MiRNA-221-5p may promote the invasive and migratory potentials of BCa by regulating E-cadherin expression.