Aberrant EphA2 overexpression causes an excess of unbound receptor and it contributes to the spread of certain solid tumors including prostate cancer [1,17], melanoma [13,18], breast cancer [2,3], brain cancer [10,19], ovarian cancer [20], urinary bladder cancer [11], pancreatic cancer [5,6,21,22], esophageal cancer [23], lung cancer [24], stomach cancer [25], and several types of leukemia [15,16]. The gene discussed is EPHA2; the disease is breast cancer.