Just to further along this train of thought, here is an excellent link to the cytochrome P450 (CPY19) activation and specifically the interaction with breast cancer.
http://www.cancerindex.org/geneweb/CYP19.htm
Also, looking at your list of natural COX2 inhibitors... scullcap can be toxic and IS toxic to anyone with liver disease, inc. mets. Here is a phase 1 trial using this herb:
http://www.abstracts2view.com/sabcs0...u=SABCS05L_136
There are also clinical trials going on testing very potent COX2 inhibitors and analogues of celebrex.
Al