Fig. 4

Knockdown of circUBE2D2 reduces doxorubicin resistance in TNBC cells. a and b Transfected MDA-MB-231 and BT-549 cells were treated with different concentrations of doxorubicin (0.01, 0.1, 1, 5, 10, 50 or 100 μM) for 48 h, followed by CCK-8 assay to measure the cell viability and IC₅₀ values of doxorubicin. c Transfected MDA-MB-231 and BT-549 cells were treated with or without 2 μM doxorubicin for 48 h, followed by flow cytometry analysis to detect cell apoptosis. **P < 0.01, ***P < 0.001