Figure 5 MALAT1 silencing promotes Adr sensitivity of breast cancer cells. (A) MCF-7 cells were exposed to gradient concentrations of Adr (Sigma-Aldrich, St Louis, MO, USA) to ensure the construction of Adr resistant breast cancer cells by CCK-8 assay. (B) The MALAT1 expression in MCF-7 cells and MCF-7/Adr cells measured by qRT-PCR. (C) The MALAT1 expression in MCF-7/Adr cells transfected with si-MALAT1 or scramble siRNA measured by qRT-PCR. (D) The cell viability of MCF-7/Adr cells when exposed to gradient concentrations of Adr determined by CCK-8 assays. (E) Apoptosis rate of the MCF-7/Adr cells examined by flow cytometry analysis. Data are expressed as mean±SD. One-way ANOVA and Sidak’s multiple comparisons test were used to determine statistical significance, otherwise unpaired t-test was used, * P<0.05, ** P<0.01. Three independent experiments were performed. MALAT1 – metastasis-associated lung adenocarcinoma transcript 1; Adr – adriamycin; CCK-8 – Cell Counting Kit-8; qRT-PCR – quantitative real-time polymerase chain reaction; SD – standard deviations.0