TRAF4 is involved in the activation of the NF-κB signalling pathway by upregulating PRMT5 and promoting its nucleus expression, and together with HER-2 ectopic expression promoting NF-κB pathway activation, high PRMT5 combined with TRAF4 expression is a poor indicator of prognosis in breast cancer patients (41). This evidence concerns the gene ERBB2 and breast cancer.