You Cheng1, Zhaoyun Li2, Jiaogui Xie3, Pan Wang2, Jie Zhu2, Yueguo Li4, Yichao Wang5. 1. Department of Clinical Laboratory Medicine, TaiZhou Central Hospital (Taizhou University Hospital), No.999 Donghai Road, Jiaojiang District, Taizhou, Zhejiang, 318000, China; School of Medical Laboratory, Tianjin Medical University, No.1 Guangdong Road, Hexi District, Tianjin, 300203, China. 2. Department of Clinical Laboratory Medicine, TaiZhou Central Hospital (Taizhou University Hospital), No.999 Donghai Road, Jiaojiang District, Taizhou, Zhejiang, 318000, China. 3. Department of Urology, The Fifteenth Military Hospital of China, Wusu, Xinjiang, 833000, China. 4. Department of Laboratory, National Clinical Research Center of Cancer, Tianjin Medical University Cancer Institute and Hospital, Tianjin, 300060, China. Electronic address: kesaqi@126.com. 5. Department of Clinical Laboratory Medicine, TaiZhou Central Hospital (Taizhou University Hospital), No.999 Donghai Road, Jiaojiang District, Taizhou, Zhejiang, 318000, China; School of Medical Laboratory, Tianjin Medical University, No.1 Guangdong Road, Hexi District, Tianjin, 300203, China. Electronic address: wangyichaobei@126.com.
Abstract
BACKGROUND/AIMS: Autophagy is known as a protective intracellular procedure, which can be regulated by several factors. MiRNA has been suggested as a potential element to mediate autophagy pathway in carcinomas. Our study was aim to investigate the role of autophagy in breast cancer cells and identify the involved molecular mechanism METHODS: The expression of LC3I/II, SQSTM1 and Smad4 were detected by western blot. The mRNA level were quantified by real-time PCR. MDC staining was used to directly visualize autophagosome formation. Target Scan 7.2 was used to predict biological targets of miR-224-5p RESULTS: MiR-224 -5p expression was upregulated in metastatic breast cancer and non-metastatic breast cancer cells compare with control. Moreover, miR-224-5p inhibition enhanced cellular autophagy levels in breast cancer cells. MiR-224-5p could suppress Smad4 expression in MDA-MB-231 cells, which indicated that Smad4 was identified as a target of miR-224-5p in breast cancer cells with high metastatic potential CONCLUSIONS: Our study revealed that miR-224-5p inhibited autophagy by targeting Smad4 in MDA-MB-231 cells. The results indicated that miR-224-5p/Smad4 regulating autophagy might be a novel regulatory network contributing to metastasis of breast cancer. MiR-224-5p and Smad4 is involved in breast tumorigenesis, which is possibly a novel target for breast cancer therapy.
BACKGROUND/AIMS: Autophagy is known as a protective intracellular procedure, which can be regulated by several factors. MiRNA has been suggested as a potential element to mediate autophagy pathway in carcinomas. Our study was aim to investigate the role of autophagy in breast cancer cells and identify the involved molecular mechanism METHODS: The expression of LC3I/II, SQSTM1 and Smad4 were detected by western blot. The mRNA level were quantified by real-time PCR. MDC staining was used to directly visualize autophagosome formation. Target Scan 7.2 was used to predict biological targets of miR-224-5p RESULTS:MiR-224 -5p expression was upregulated in metastatic breast cancer and non-metastatic breast cancer cells compare with control. Moreover, miR-224-5p inhibition enhanced cellular autophagy levels in breast cancer cells. MiR-224-5p could suppress Smad4 expression in MDA-MB-231 cells, which indicated that Smad4 was identified as a target of miR-224-5p in breast cancer cells with high metastatic potential CONCLUSIONS: Our study revealed that miR-224-5p inhibited autophagy by targeting Smad4 in MDA-MB-231 cells. The results indicated that miR-224-5p/Smad4 regulating autophagy might be a novel regulatory network contributing to metastasis of breast cancer. MiR-224-5p and Smad4 is involved in breast tumorigenesis, which is possibly a novel target for breast cancer therapy.
Authors: Julia O Misiorek; Anna M Schreiber; Martyna O Urbanek-Trzeciak; Magdalena Jazurek-Ciesiołka; Lauren A Hauser; David R Lynch; Jill S Napierala; Marek Napierala Journal: Mol Neurobiol Date: 2020-04-14 Impact factor: 5.590