Westerns showed increased expression of ROR1 in the neuroendocrine prostate cancer cell lines, PC3 and DU145, and a patient derived xenograft (PDX) model of small cell bone metastatic prostate cancer, PCSD13….Intravenous infusion of anti-ROR1 CAR-T cells into mice bearing subcutaneous, ROR1-expressing, PC3 xenografts, showed marked reduction in tumor growth. ROR1 Knock out using CRISPR-Cas9 in PC3 and DU145 cells showed specificity of Cirmtuzumab-based immunotherapies.