Knockdown of TFAP2B accelerates cell cycle progression upon RA treatment in neuroblastoma cells. (a) Knockdown efficiency of TFAP2B in SH‐SY5Y and SK‐N‐BE(2)c cells as determined by Western blot analysis; e.v., empty vector control. (b) Cell cycle analysis of SH‐SY5Y and SK‐N‐BE(2)c cells after treatment with 1 μM RA for 6 days and 10 days, respectively. Error bars indicate S.D; (*), p < 0.05; (**), p < 0.01; (***), p < 0.001.