ERBB3 and melanoma: However, these findings contradict a study utilising B16-BL6 melanoma cells indicating that ERBB3, when dimerised with EGFR, is essential for tumour metastasis both in vitro and in vivo, and upregulates mesenchymal genes downstream of MAPK, JNK and PI3K-Akt pathway activation (Ueno et al., 2008).