Analysis of transgenic neu promoter activity in MCF-7 cells. (A) RT-PCR of MCF-7 cells transfected with pNcN construct or vector alone. The mammary cell line 980NF was derived from an MMTV-neu*–induced tumor and serves as positive control. Reverse transcription was performed with either Superscript II RT or water and cDNA was amplified using SV40 polyA primers. (B) β-actin is amplified from the cDNAs to show consistent loading.