HER2 Support Group Forums - View Single Post - getting her2+ER- bc to reexpress ER & consequences more complicated than thought

Lani · 01-02-2010, 11:00 AM

the reason I said it was more complicated than previously thought--many of you who are her2+er- have wished to be transformed into her2+er+ by treatments restoring ER expression--in your posts you stated "then I could be treated with AIs AND herceptin and have more treatment options"

As it turns out, when ER was reintroduced in this study, estrogen itself was what inhibited growth, NOT antiestrogens

I refer to the following sentences:

The growth of SKBr3(a her2+er cell line) was inhibited by ERalpha expression and further inhibited in the presence of 1 nM 17beta-estradiol.

Paradoxically, estrogen inhibits breast cancer cell growth when an exogenous ERalpha is expressed

Estrogen also reduced EGFR and HER2 expression in SKBr3 cells after ERalpha was expressed.

How ER(alpha and beta) and her2 interact is complicated and is still being worked out.

01-02-2010, 11:00 AM	#7
Lani Senior Member Join Date: Mar 2006 Posts: 4,778	Re: getting her2+ER- bc to reexpress ER & consequences more complicated than thought the reason I said it was more complicated than previously thought--many of you who are her2+er- have wished to be transformed into her2+er+ by treatments restoring ER expression--in your posts you stated "then I could be treated with AIs AND herceptin and have more treatment options" As it turns out, when ER was reintroduced in this study, estrogen itself was what inhibited growth, NOT antiestrogens I refer to the following sentences: The growth of SKBr3(a her2+er cell line) was inhibited by ERalpha expression and further inhibited in the presence of 1 nM 17beta-estradiol. Paradoxically, estrogen inhibits breast cancer cell growth when an exogenous ERalpha is expressed Estrogen also reduced EGFR and HER2 expression in SKBr3 cells after ERalpha was expressed. How ER(alpha and beta) and her2 interact is complicated and is still being worked out.