Department of Breast Surgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
Department of Medical Oncology, Xuzhou Central Hospital, Xuzhou, China.
Thorac Cancer. 2020 Apr;11(4):956-963. doi: 10.1111/1759-7714.13348. Epub 2020 Feb 26.
Breast cancer is the most common malignant tumor in women worldwide, with a high mortality rate. MicroRNAs are small non-coding RNAs that negatively regulate the expression of target genes by interacting with the target gene 3'-UTR, and participate in cell differentiation, proliferation, apoptosis and metabolism. The function of miRNA-96-5p in the progression of breast cancer has not been reported.
We used the StarBase database to investigate the expression of miRNA-96-5p in breast cancer and adjacent normal tissues. FOXO3 3'-UTR construct and luciferase reporter assays was performed for the target gene. Expression levels of miRNAs including its target were analyzed by qRT-PCR and western blot. Cell proliferation was detected by CCK8 and colony formation, EdU assay.
Luciferase reporter assays showed miRNA-96-5p directly targeted FOXO3. Abrogation of miRNA-96-5p by transfection with its inhibitors in breast cancer cells significantly suppressed miRNA-96-5p expression and breast cancer cells proliferation. Western blot revealed that overexpression of miRNA-96-5p substantially reduced FOXO3 protein expression. We used the GEPIA, UALCAN and KM-plotter databases to investigate the expression of FOXO3 in human breast cancer and adjacent normal tissues, and its correlation with survival. In addition, we found that FOXO3 spoiled miR-96-5p induced breast cancer cell proliferation block effecting.
miRNA-96-5p may exert a tumor promotion role through negatively regulating tumor suppressor gene FOXO3 and promoting cell proliferation.
乳腺癌是全球女性中最常见的恶性肿瘤，死亡率较高。miRNA 是一种小的非编码 RNA，通过与靶基因 3'-UTR 相互作用负调控靶基因的表达，参与细胞分化、增殖、凋亡和代谢。miRNA-96-5p 在乳腺癌进展中的作用尚未报道。
我们使用 StarBase 数据库研究 miRNA-96-5p 在乳腺癌及相邻正常组织中的表达。构建 FOXO3 3'-UTR 载体和荧光素酶报告基因检测其靶基因。通过 qRT-PCR 和 Western blot 分析 miRNA 及其靶基因的表达水平。通过 CCK8 法和集落形成实验、EdU 实验检测细胞增殖。
荧光素酶报告基因实验显示 miRNA-96-5p 可直接靶向 FOXO3。用其抑制剂转染乳腺癌细胞可显著抑制 miRNA-96-5p 的表达并抑制乳腺癌细胞的增殖。Western blot 显示过表达 miRNA-96-5p 可显著降低 FOXO3 蛋白的表达。我们使用 GEPIA、UALCAN 和 KM-plotter 数据库研究了 FOXO3 在人乳腺癌及相邻正常组织中的表达及其与生存的关系。此外，我们发现 FOXO3 可削弱 miR-96-5p 诱导的乳腺癌细胞增殖阻滞作用。
miRNA-96-5p 可能通过负调控抑癌基因 FOXO3 促进细胞增殖，发挥促肿瘤作用。
