Effect of zfp67 on transcription of CDCP1. (a) DNA sequence between nt −150 and −130. The putative binding motif for zfp67 was underlined. (b) Luciferase assay with the reporter plasmid mutated at the zfp67 binding motif. The values represent the mean±s.e. of three experiments. *P<0.05 by t-test when compared to the value with the reporter plasmid that contained unmutated zfp67 motif. (c) Immunoblot analysis. The siRNA against zfp67 was transfected into K562, and the amount of zfp67 was examined with immunoblot. (d) Expression of CDCP1 in zfp67-knocked down K562. By real-time PCR, the amount of CDCP1 mRNA was quantified and normalized for the amount of GAPDH mRNA. The values represent the mean±s.e. of three experiments. *P<0.05 by t-test when compared to the value of original K562.