FOXP1 and marginal zone lymphoma: also revealed the overexpression of FOXP1 and the Casitas B-lineage lymphoma b gene (CBLB). FOXP1 overexpression is widely accepted to be a factor of poor prognosis in activated B-cell-like subtype diffuse large B-cell lymphoma and marginal zone B-cell lymphoma, mucosa-associated lymphoid tissue type [33, 34].