Using a combination of molecular, pharmacological and functional approaches, we have validated a number of these targets, and further dismantled their signaling pathway linking CD44 activation to their transcription (7–11).An additional upregulated gene, the pre-mRNA cleavage complex 2 (PCF11) was selected from the CHIP screen for further investigation based on several lines of evidence supporting the hypothesis that PCF11 is a transcriptional target that underpins CD44-promoted BC tumor cell invasion. This evidence concerns the gene PCF11 and breast cancer.