Breast cancer tumorigenesis is a multi-step process where each step correlates with one or more distinct mutations in regulatory genes. Based on the set of genes that are mutated, breast cancer can be classified into hereditary or sporadic forms. HER-2/ERBB2 (Human Epidermal Growth Factor Receptor-2) mutations play a role in sporadic breast cancer. HER-2 is overexpressed in 25-30% of breast cancer cases. Overexpression of HER-2 occurs either through gene amplification or transcriptional deregulation...