Receptor tyrosine kinase-like orphan receptor 1 (ROR-1): An emerging target for diagnosis and therapy of chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is characterized by reposition of malignant B cells in the blood, bone marrow, spleen and lymph nodes. It remains the most common leukemia in the Western world. Within the recent years, major breakthroughs have been made to prolong the survival and improve the health of patients. Despite these advances, CLL is still recognized as a disease without definitive cure. New treatment approaches, based on unique targets and novel drugs, are highly desired for CLL therapy. The Identification and subsequent targeting of molecules that are overexpressed uniquely in malignant cells not normal ones play critical roles in the success of anticancer therapeutic strategies. In this regard, ROR family proteins are known as a subgroup of protein kinases which have gained huge popularity in the scientific community for the diagnosis and treatment of different cancer types. ROR1 as an antigen exclusively expressed on the surface of tumor cells can be a target for immunotherapy. ROR-1 targeting using different approaches such as siRNA, tyrosine kinase inhibitors, cell therapy and antibody induces tumor growth suppression in cancer cells. In the current review, we aim to present an overview of the efforts and scientific achievements in targeting ROR family, particularly ROR-1, for the diagnosis and treatment of chronic lymphocytic leukemia (CLL).