PDS5A overexpression reverses the consequences of CDCA5 inhibition in breast cancer cell proliferation. (A) Overexpression of PDS5A was detected by western blotting. (B) Cell Counting Kit-8 assay detected increased level of cell proliferation in MDA-MB-231 cells. (C) Colony formation assay was used to detect the colony formation ability of MDA-MB-231 cells. (D) Expression levels of the proliferation-related proteins Ki67 and PCNA were increased after being initially reduced, as indicated by western blotting. **P<0.01 and ***P<0.001 vs. shRNA-CDCA5-2 + pcDNA3.1-NC; ##P<0.01 vs. pcDNA3.1-NC. CDCA5, cell division cycle-associated 5; sh, short hairpin; NC, negative control; PCNA, proliferating cell nuclear antigen; OD, optical density; PDS5A, PDS5 cohesin-associated factor A.