MYBBP1A suppresses colony formation and tumorigenesis in vitro and in vivo.(A) and (B) Efficiency of MYBBP1A knockdown and overexpression in MCF-7 cells. (A) western blot with anti-MYBBP1A antibody was used to detect MYBBP1A protein in MCF-7 cells that stably expressed shRNA for MYBBP1A (shMYBBP1A #1 and shMYBBP1A #2), cells that expressed Luciferase shRNA (shControl), cells that stably overexpressed MYBBP1A (OE MYBBP1A), and EGFP (OE Control). (B) MYBBP1A mRNA in these cells was quantified by RT–qPCR. (C) Effects of MYBBP1A expression on colony formation. Number of colonies per dish (area = 9.4 cm2) are shown. (D) Tumor growth curves in nude mice that were inoculated with either shControl, shMYBBP1A #1, OE Control, or OE MYBBP1A MCF‐7 cells. Nude mice received bilateral subcutaneous injections of control or cells. Tumor volume is presented as the mean ± s.d. (n = 10) for 5 mice in each group. (E) and (F) Increased or decreased tumor weight in mice injected with shMYBBP1A #1 or OE MYBBP1A cells. Photographs of mice (E) and tumors (F, right panels) are shown. Scale bars = 10 mm. Tumor weights after 49 days are shown in F, left panel. Bars = mean + s.d. (n = 10).