ERBB2 and breast adenocarcinoma: The chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3) cell type over-expresses EGFR (2.2 × 105/cell) and highly over-expresses HER2/neu (1 × 106/cell) on its exterior surface membrane which promotes selectively “targeted” delivery and progressive membrane deposition of gemcitabine-(C4-amide)-[anti-EGFR] and gemcitabine-(C4-amide)-[anti-HER2/neu] at two different endogenous trophic membrane receptor sites.