MALT1 and MALT lymphoma: Especially in MALT lymphomas with t(11;18)(q21;q21)/BIRC3-MALT1, the resulting BIRC3-MALT1 fusion product forms self-oligomers via a non-homotypic interaction mediated by the BIRC3 moiety, leading to constitutive nuclear factor kappa B (NF-κB) activation.