Figure 6. HOTAIR knockdown switches cell cycle and up-regulates PCNA expression of iMAD cells. (A) Cell cycle analysis. Subconfluent iMAD-KD and iMAD-Ctrl were infected with Ad-BMP9 or Ad-GFP. At 36 h after infection, cells were collected, fixed, stained with Hoechst 33342, and subjected to FACS analysis. Assays were done in triplicate, and representative results are shown. (B) Immunohistochemical (IHC) expression analysis of cell proliferation marker PCNA. The retrieved bone masses were sectioned and subjected to IHC staining with either a negative control IgG or PCNA antibody. Representative results are shown. Yellow arrows show positive staining cells.