We investigated alterations of ERBB proteins in LRIG1-mediated inhibition of PCa using the PCa cell and xenograft models described earlier, all of which expressed EGFR at various levels while only some expressed ERBB2 and ERBB3 (Supplementary Fig. 6b) with no appreciable ERBB4 in any of the models. Here, ERBB4 is linked to posterior cortical atrophy.