al from canada

Lynnw,

Here is a posting where this was discussed:

http://www.her2support.org/forums/index.ph...ptin++tamoxifen

Here is a quote from one of the articles:

"Another observation of relevance to this discussion is that tamoxifen has estrogen agonist effects and causes significant elevations of plasma oestradiol levels in most premenopausal and some postmenopausal patients [57]. Recent studies have indicated that MEKK1, a downstream mediator of HER2 signalling, activates ER and stimulates the agonist activity of tamoxifen [58]. Thus, HER2 positivity and increased downstream signalling could potentially convert tamoxifen from a breast cancer cell inhibitor into a stimulatory agent."

Regards

Al