To dissect the possible molecular mechanisms how an aberrant interplay of PRMT5 and KLF4 contributes to breast tumor initiation and progression, we performed gene array assays and identified the downstream gene network responding to the aberrant KLF4 methylation by PRMT5 by using a customized breast cancer gene profile with quantitative real-time PCR (qPCR) array from SABiosciences (Fig. 6e)48, 49. The gene discussed is KLF4; the disease is breast cancer.