Targeting human breast cancer cells that overexpress HER-2/neu mRNA by an antisense iron responsive element.

The overexpression of HER-2/neu proto-oncogene has been found in a variety of human cancers. In particular, the amplification and overexpression of HER-2/neu gene were found in 20-30% of breast and ovarian cancer patients with a decreased survival and an increased relapse rates. To target the breast cancer cells overexpressing HER-2/neu mRNA, a novel approach is described that combines the antisense principle and the biochemical property of a translation regulator, an iron responsive element (IRE). This report shows that a HER-2/neu antisense IRE-reporter gene can be preferentially expressed in the breast cancer cells that overexpress HER-2/neu mRNA. This antisense IRE-mediated gene expression system may be applied broadly to target other cell type that uniquely expresses or overexpresses a known gene.