ROR1 and B-cell chronic lymphocytic leukemia: ROR1 expression was evaluated in both hematological malignancies and solid tumors and has been associated with poor outcome and reduced therapeutic responses in several cancers including breast cancer [57, 66], CLL [26, 52, 67, 68], colorectal cancer [69], endometrial cancer [70], lung adenocarcinoma [71], melanoma [63] and ovarian cancer [72, 73].