ABSTRACT
OBJECTIVE: This study aimed at exploring the role of α-enolase (ENO1) in proliferation, invasion, and cell apoptosis in MDA-MB-231 and MCF-7 breast cancer human cells, to provide a theoretical basis for the clinical treatment of breast cancer. MATERIALS AND METHODS: MDA-MB-231 and MCF-7 cells were randomly divided into five groups: normal control group (Control group), negative control group (negative control virus, NC group), and shENO1 (sh1, sh2, and sh3) group, respectively. The expressions of ENO1 mRNA and protein were measured by Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) and Western blot, respectively. Cell proliferation, cell invasion ability, and cell apoptosis rate were detected by methyl thiazolyl tetrazolium (MTT) assay, transwell invasion assay, and flow cytometer, respectively. The expressions of the proteins correlated with phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway were analyzed by Western blot. RESULTS: In MDA-MB-231 and MCF-7 cells, the gene and protein expressions of ENO1 in the three sh groups in MDA-MB-231 and MCF-7 cells were significantly lower than those in control group and NC group. In MDA-MB-231 and MCF-7 cells, the gene and protein expressions of ENO1 in the three sh groups were significantly lower than those in control group and NC group. Compared with NC group, the proliferation activity, invasion ability, and apoptosis rate of shENO1 group were significantly decreased (p < 0.01). PI3K and Akt protein levels in shENO1 group were significantly downregulated (p < 0.01). Bcl-2 protein expression was markedly upregulated (p < 0.01), meanwhile Bax protein revealed a significant reduction (p < 0.01). CONCLUSIONS: The results revealed that silencing ENO1 reduced proliferation activity, invasion ability, and apoptosis rate of breast cancer cells by decreasing the phosphorylation of PI3K and Akt pathway. Our results suggested that ENO1 may be a potential therapeutic target in breast cancer.
Subject(s)
Biomarkers, Tumor/metabolism , Breast Neoplasms/metabolism , DNA-Binding Proteins/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Phosphopyruvate Hydratase/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Tumor Suppressor Proteins/metabolism , Apoptosis , Biomarkers, Tumor/genetics , Breast Neoplasms/pathology , Cell Proliferation , DNA-Binding Proteins/genetics , Humans , MCF-7 Cells , Phosphopyruvate Hydratase/genetics , Phosphorylation , RNA, Messenger/genetics , RNA, Messenger/metabolism , Signal Transduction , Tumor Cells, Cultured , Tumor Suppressor Proteins/geneticsABSTRACT
OBJECTIVE: The aim of this study was to investigate the influence of micro ribonucleic acid (miR)-34a on resistance to sunitinib in breast cancer, and to explore its possible underlying mechanism. MATERIALS AND METHODS: Breast cancer MCF-7 cells were transfected with miR-34a inhibitor or mimics to downregulate or upregulate the expression of miR-34a. Then, the transfected cells were treated with sunitinib. Next, transwell assay was applied to detect the changes in cell invasion ability. Cell viability was measured via cell counting kit-8 (CCK8) assay. Dual-Luciferase reporter gene assay was employed to determine the interaction between miR-34a and the Wnt/ß-catenin signaling pathway. The immunoblotting assay was used to measure the expression changes of proteins in the pathway. RESULTS: The overexpression of miR-34a significantly reduced the invasive ability of MCF-7 cells after treatment with sunitinib. After miR-34a expression was downregulated, the sensitivity of MCF-7 cells to sunitinib was significantly lowered. MiR-34a interacted with the 3'-untranslated region (3'-UTR) on Wnt1. Meanwhile, the overexpression of miR-34a remarkably downregulated the messenger RNA (mRNA) and the protein levels of Wnt1, whereas upregulated the expressions of Wnt1 and ß-catenin. CONCLUSIONS: MiR-34a affects the sensitivity to sunitinib in breast cancer by regulating the Wnt/ß-catenin signaling pathway.
