STING Pathway Activation: The Missing Link between Genomic Instability and Antitumor Immunity in Osteosarcoma
Project Goal:
Project Update 2024:
In cancers including osteosarcoma (OS), malfunctioning DNA replication results in a warning signal to the immune system via the cGAS-STING pathway, which we believe is modified in OS tumors to evade immune-mediated tumor killing. We have identified that about 50% of OS patient-derived cell lines respond to cGAS-STING activation with a drug treatment, whereas the other half do not. Additionally, using RNA sequencing, we defined the specific genetic changes that occur in OS upon activation of the cGAS-STING pathway. Our preliminary studies of a STING activating drug in animal models have shown that this therapy can slow tumor growth and increase anti-tumor immunity. Overall, we have discovered two subsets of OS with differing capacity to generate an anti-tumor immune signal and demonstrated the benefits of activating STING in patients and in immune assays. Our proposed ongoing work will confirm the effects of STING activation, supporting the translation of this novel approach to activating immune surveillance in osteosarcoma.