Recent studies AXL to be a marker for poor prognosis in lung cancers [6], breast cancers [7], pancreatic cancer [8], renal cell carcinoma [9] and ovarian cancer [10], and for treatment resistance in lung cancers [11–13], gastrointestinal stromal tumor [14], esophageal cancer [15], and ovarian cancer [16]. Here, AXL is linked to breast cancer.