TYRO3: A potential therapeutic target in cancer

TYRO3 belongs to the TAM (TYRO3, AXL, and MER) receptor family, a unique subfamily of the receptor tyrosine kinases. Members of TAM family share the same ligand, growth arrest-specific 6, and protein S. Although the signal transduction pathways of TYRO3 have not been evaluated in detail, overexpression and activation of TYRO3 receptor tyrosine kinase have been reported to promote cell proliferation, survival, tumorigenesis, migration, invasion, epithelial-mesenchymal transition, or chemoresistance in several human cancers. Targeting TYRO3 could break the kinase signaling, stimulate antitumor immunity, reduce tumor cell survival, and regain drug sensitivity. To date, there is no specific TYRO3-targeted drug, the effectiveness of targeting TYRO3 in cancer is worthy of further investigations. In this review, we present an update on molecular biology of TYRO3, summarize the development of potential inhibitors of TAM family members, and provide new insights in TYRO3-targeted treatment. Impact statement: Cancer is among the leading causes of death worldwide. In 2016, 8.9 million people are estimated to have died from various forms of cancer. The current treatments, including surgery with chemotherapy and/or radiation therapy, are not effective enough to provide full protection from cancer, which highlights the need for developing novel therapy strategies. In this review, we summarize the molecular biology of a unique member of a subfamily of receptor tyrosine kinase, TYRO3 and discuss the new insights in TYRO3-targeted treatment for cancer therapy.