ERBB3 and breast cancer: We had shown in previous studies that Th1 cytokines could cause a down-regulation of HER-2 and HER-3 in some breast cancer lines (while expression of other proteins like EpCAM were unperturbed), and this suppression, at least for HER-2, could be enhanced by the addition of the small molecule inhibitor of HER-2 and EGFR, lapatinib [6, 16].