Relative abundance of full-length and truncated FOXP1 isoforms is associated with differential NFkappaB activity in Follicular Lymphoma.

FOXP1 is a transcriptional repressor that has been proposed to repress the expression of some NFkappaB-responsive genes. Furthermore, truncated forms of FOXP1 have been associated with a subtype of Diffuse Large B-cell Lymphoma characterised by constitutive NFkappaB activity, indicating that they may inhibit this repression. We have shown that FL tumors have increased relative abundance of truncated FOXP1 isoforms and this is associated with increased expression of NFkappaB-associated genes. Our results provide strong evidence that relative FOXP1 isoform abundance is associated with NFkappaB activity in FL, and could potentially be used as a marker for this gene signature.