ERBB2 and breast cancer: Taking into account the involvement of EGFR/HER2 receptors in the E2-induced activation of cPLA2α in breast cancer cell lines, it was hypothesised that cPLA2α activity and expression could be correlated with HER2-overexpressing tumours, a suggestion that is also supported by previous studies showing a correlation between expression of intermediates in the eicosanoid signalling pathway, particularly COX-2, and HER2 over-expression in breast cancer (Vadlamudi et al, 1999; Ristimaki et al, 2002; Subbaramaiah et al, 2002; Wulfing et al, 2003).