Jing Ke1, Quhui Wang1, Wei Zhang1, Sujie Ni2, Haijun Mei1. 1. Department of General Surgery, Affiliated Hospital of Nantong University Nantong 226001, Jiangsu Province, China. 2. Department of Medical Oncology, Affiliated Hospital of Nantong University Nantong 226001, Jiangsu Province, China.
Abstract
OBJECTIVE: Breast cancer, as a malignancy with the highest incidence and mortality in women, seriously threatens women's life and health. Pieces of evidence have suggested that long non-coding RNAs (lncRNAs) possess important roles in regulating the occurrence and development of breast cancer. METHODS: RT-qPCR was used to explore the expression levels of MIR4435-2HG, miR-22-3p and TMEM9B in breast cancer tissues and cell lines. Cell viability, proliferation, migration and invasion were assessed by CCK-8 assay, Colony formation assay, Wound healing assay and Transwell assay, respectively. The effect of MIR4435-2HG on EMT progress was explored by Immunofluorescence assay and Western blot. RNA pull-down analysis and Dual-luciferase reporter assay were performed to validate the interaction between MIR4435-2HG and miR-22-3p, as well as miR-22-3p and TMEM9B. RESULTS: MIR4435-2HG was notably up-regulated in breast cancer tissues and cell lines. Additionally, down-regulation of MIR4435-2HG restrained the viability, proliferation, migration, invasion and EMT of breast cancer cells. MiR-22-3p expression was down-regulated in breast cancer tissues and cell lines, and negatively associated with MIR4435-2HG expression. Over-expression of miR-22-3p obviously inhibited the viability, proliferation, migration, invasion and EMT of breast cancer cell lines. Furthermore, TMEM9B was up-regulated in breast cancer tissues and cell lines and negatively associated with miR-22-3p expression. TMEM9B inhibition partially restored the effects of MIR4435-2HG/miR-22-3p on the viability, proliferation, migration, invasion and EMT of breast cancer cell lines. CONCLUSION: MIR4435-2HG plays a potential tumor-promoting role in the occurrence and development of breast cancer, possibly by regulating the miR-22-3p/TMEM9B axis. AJTR
OBJECTIVE: Breast cancer, as a malignancy with the highest incidence and mortality in women, seriously threatens women's life and health. Pieces of evidence have suggested that long non-coding RNAs (lncRNAs) possess important roles in regulating the occurrence and development of breast cancer. METHODS: RT-qPCR was used to explore the expression levels of MIR4435-2HG, miR-22-3p and TMEM9B in breast cancer tissues and cell lines. Cell viability, proliferation, migration and invasion were assessed by CCK-8 assay, Colony formation assay, Wound healing assay and Transwell assay, respectively. The effect of MIR4435-2HG on EMT progress was explored by Immunofluorescence assay and Western blot. RNA pull-down analysis and Dual-luciferase reporter assay were performed to validate the interaction between MIR4435-2HG and miR-22-3p, as well as miR-22-3p and TMEM9B. RESULTS: MIR4435-2HG was notably up-regulated in breast cancer tissues and cell lines. Additionally, down-regulation of MIR4435-2HG restrained the viability, proliferation, migration, invasion and EMT of breast cancer cells. MiR-22-3p expression was down-regulated in breast cancer tissues and cell lines, and negatively associated with MIR4435-2HG expression. Over-expression of miR-22-3p obviously inhibited the viability, proliferation, migration, invasion and EMT of breast cancer cell lines. Furthermore, TMEM9B was up-regulated in breast cancer tissues and cell lines and negatively associated with miR-22-3p expression. TMEM9B inhibition partially restored the effects of MIR4435-2HG/miR-22-3p on the viability, proliferation, migration, invasion and EMT of breast cancer cell lines. CONCLUSION: MIR4435-2HG plays a potential tumor-promoting role in the occurrence and development of breast cancer, possibly by regulating the miR-22-3p/TMEM9B axis. AJTR