Synovial sarcoma is a soft tissue malignancy of the muscle that primarily affects adolescents. Due to it low incidence, little advancement has been made in the treatment of this cancer. With an overall survival rate of roughly 40%, the need for new treatments for synovial sarcoma is evident. Oncostatin M Receptor (OSMR) is a type I cytokine receptor and is overexpressed in metastatic synovial sarcoma. OSMR does not have high expression in normal tissues, making it an ideal target for cancer therapy. We hypothesize that by using an anti-OSMR monoclonal antibody conjugated to a radioactive Cu67 isotope, synovial sarcoma can be targeted at both primary and metastatic locations through systemic therapy. Copper67 is a beta radiation emitting isotope that is tissue damaging and able to induce cell death in cancer cells. By conjugating the chelating molecule p-SCN-Bn-NOTA to an anti-OSMR antibody, Cu67 was able to be captured to the antibody. Capture efficiency of Cu67 was measured after TLC separation and found to be 80% efficient. This data suggests that targeting OSMR through radioimmunotherapy (RIT) is a viable treatment and indicates further testing in animal models.

Citation Format: Sarah Luelling, Matthew Kirkham, Jared Barrott. Oncostatin M receptor as a therapeutic target of radioimmune therapy in metastatic synovial sarcoma [abstract]. In: Abstracts: AACR Virtual Special Conference: Tumor Immunology and Immunotherapy; 2020 Oct 19-20. Philadelphia (PA): AACR; Cancer Immunol Res 2021;9(2 Suppl):Abstract nr PO042.