However, we note that disrupting the BH3 domain or the amino-terminal LXXLL motif of ErbB4 abrogates the tumor suppressor activity of the ErbB4 Q646C mutant, suggesting that ErbB4 targeting to the nucleus and mitochondria is important for the tumor suppressor activity of the ErbB4 Q646C mutant. Here, ERBB4 is linked to neoplasm.