Inhibition of erbB-2-positive breast cancer cell growth by erbB-2 antisense oligonucleotides.

Overexpression of erbB-2 proto-oncogene has been found in 20%-30% of human breast carcinomas and in most cases correlates with poor clinical prognosis. Using antisense oligonucleotides targeted to the 5' cap region of erbB-2RNA, we were able to inhibit erbB-2 protein expression, proliferation, and anchorage-independent growth of breast cancer cells up to 90%. These effects were sequence specific and restricted to cells expressing elevated level of erbB-2 protein. These support the feasibility of using antisense erbB-2 oligonucleotides to inhibit the progression of erbB-2-overexpressing breast cancer cells.