Chao Zhang1, Ting Yang2, Hongchuan Jiang1. 1. Departments of Breast Surgery, Chaoyang Hospital, Capital Medical University, Bejing, China. 2. Departments of General Surgery, New Century Women's and Children's Hospital, Beijing, China.
Abstract
BACKGROUND: The present study aimed to explore the functions and molecular mechanisms of miR-511 in breast cancer. METHODS: A quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect miR-511 levels in breast cancer tissues; a chi-squared test was used to analyze the relationship between miR-511 expression level and pathological parameters of breast cancer patients; the proliferation of breast cancer cell lines MDA-MB-231 and MCF-7 was determined by the cell counting kit-8 (CCK-8) assay; migration was determined by scratch wound healing assay and transwell assay; TargetScan was used to predict the binding site between the 3'-untranslated region (3'-UTR) of fibroblast growth factor 4 (FGF4) and miR-511; and qRT-PCR, western blot and a luciferase reporter gene assay were conducted to further validate the targeting relationship between miR-511 and FGF4. RESULTS: The expression level of miR-511 was lower in breast cancer tissues than that in adjacent normal tissues. Low expression of miR-511 was associated with larger tumor size, lymph node metastasis and short survival time. In vitro experiments showed that miR-511 modulated the proliferation and metastasis of breast cancer cells. It was also confirmed that miR-511 directly targeted 3'-UTR of FGF4 and reduced its expression, and FGF4 overexpression reversed the effect of miR-511 on the malignant phenotypes of breast cancer cells. CONCLUSIONS: The results obtained in the present study demonstrate that miR-511 inhibits breast cancer proliferation and metastasis by down-regulating FGF4 expression, which may be helpful in the development of new treatment strategies for breast cancer.
BACKGROUND: The present study aimed to explore the functions and molecular mechanisms of miR-511 in breast cancer. METHODS: A quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect miR-511 levels in breast cancer tissues; a chi-squared test was used to analyze the relationship between miR-511 expression level and pathological parameters of breast cancerpatients; the proliferation of breast cancer cell lines MDA-MB-231 and MCF-7 was determined by the cell counting kit-8 (CCK-8) assay; migration was determined by scratch wound healing assay and transwell assay; TargetScan was used to predict the binding site between the 3'-untranslated region (3'-UTR) of fibroblast growth factor 4 (FGF4) and miR-511; and qRT-PCR, western blot and a luciferase reporter gene assay were conducted to further validate the targeting relationship between miR-511 and FGF4. RESULTS: The expression level of miR-511 was lower in breast cancer tissues than that in adjacent normal tissues. Low expression of miR-511 was associated with larger tumor size, lymph node metastasis and short survival time. In vitro experiments showed that miR-511 modulated the proliferation and metastasis of breast cancer cells. It was also confirmed that miR-511 directly targeted 3'-UTR of FGF4 and reduced its expression, and FGF4 overexpression reversed the effect of miR-511 on the malignant phenotypes of breast cancer cells. CONCLUSIONS: The results obtained in the present study demonstrate that miR-511 inhibits breast cancer proliferation and metastasis by down-regulating FGF4 expression, which may be helpful in the development of new treatment strategies for breast cancer.