However, unfavourable associations between p130Cas expression and breast cancer recurrence and resistance to tamoxifen (van der Flier et al, 2000, 2001) and our identification (as described here) of SNIP/p140Cap in breast tumours – but not in normal breast tissue – and its association with larger tumours and shorter survival times from diagnosis, suggest that its effects may, at least in part, be due to an involvement with p130Cas. This evidence concerns the gene BCAR1 and breast cancer.