MD Anderson is supposed to run a clinical trial with either RAD001 (everolimus) or triciribine, which are PI3K inhibitors in the hope that they will overcome the absence of PTEN in making Herceptin active against resistant HER-2 positive cancer cells according to this piece of 2006 news:
http://www.news-medical.net/print_article.asp?id=17230
Lack of response to herceptin may be reversed with PI3K inhibiting agents