NKX3.1 binds to the NBSs of the PCAN1 promoter in living cells. LNCaP cells transfected with pcDNA3.1-NKX3.1 were cross-linked by formaldehyde treatment and lysed. Cell lysates were subjected to immunoprecipitation with either an antibody to NKX3.1 (A) or rabbit IgG (B). Four primers (names and sequences are shown in Table 1) spanning five NBSs of PCAN1 promoter region were used for PCR of recovered DNA from the immunoprecipitation (lanes 2–5). Input DNA was used as positive control (C).