Evaluation of Cancer-testis Antigens in Osteosarcoma and Dedifferentiated Liposarcoma as Targets for Immunotherapy

Description

The presentation by Anna Jirovec discusses recent findings on cancer-testis antigens in the context of aggressive malignancies such as osteosarcoma and dedifferentiated liposarcoma. Firstly, Jirovec highlights the role of the immune system in cancer treatment, specifically the promise of immunotherapies leveraging target antigens, particularly cancer testis antigens, which are almost exclusively expressed in cancer cells and not in normal tissues. The evaluation focuses on three highly immunogenic cancer-testis antigens (NY-ESO-1, MAGE-A3, and SSX2), previously linked to these sarcoma subtypes and utilized in clinical trials. The study aims to address the currently limited data on antigen expression, employing larger sample sizes for more robust findings. Using methods like IHC and nCounter Nanostring, results reveal minimal antigen expression in dedifferentiated liposarcoma, while osteosarcoma shows significant expression levels of MAGE-A3 and SSX2, suggesting potential therapeutic targets. Additionally, profiling of dedifferentiated liposarcoma tumors identifies three highly expressed antigens (TTK, PBK, SPA17) and indicates a notable inflamed immune profile in many tumors. The conclusion suggests further investigation of identified antigens and the design of future immunotherapy strategies based on these findings, with next steps including confirmation of protein expression through IHC.

DOI: 10.1302/3114-210179

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