Furthermore, overexpression of full-length FOXP1 or this small FOXP1 isoform in primary B cells and diffuse large B-cell lymphoma cell lines resulted in similar gene regulation.
The ratio of FOXP1L:FOXP1S isoforms correlated with differential expression of plasmacytic differentiation markers in U-2932 subpopulations, and altering this ratio was sufficient to modulate CD19 expression in diffuse large B-cell lymphoma cell lines.
Our study revealed that non-IG rearrangements of FOXP1 are usually acquired during clinical course of various lymphoma subtypes, including diffuse large B cell lymphoma, marginal zone lymphoma and chronic lymphocytic leukemia, and correlate with a poor prognosis.
Reciprocal expression of the endocytic protein HIP1R and its repressor FOXP1 predicts outcome in R-CHOP-treated diffuse large B-cell lymphoma patients.
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.
Based on FOXP1 presence in MM and its role in diffuse large B-cell lymphoma and extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue, FOXP1 might play an important role in plasma cell neoplasm.
Three copies of the FOXP1 gene were observed in MALT lymphoma (17%), MALT lymphoma with diffuse large B-cell lymphoma (12%) and diffuse large B-cell lymphoma (32%), including cases with FOXP1 translocation (19%).
Forkhead box protein P1 expression in mucosa-associated lymphoid tissue lymphomas predicts poor prognosis and transformation to diffuse large B-cell lymphoma.