Abstract IA035: DCIS to IDC progression - a key step of immune escape


 The cellular and molecular mechanisms underlying ductal carcinoma in situ (DCIS) to invasive ductal carcinoma (IDC) transition are poorly understood. We have analyzed genetic, gene expression, epigenetic profiles of cells composing the tumor and identified cell type-specific changes during tumor progression. Importantly, we detected significant changes in the immune cell composition during tumor progression implying immune escape in invasive tumors and active adaptive immune response in DCIS. We demonstrate that these progression stage-specific alterations are also present in a rat model of breast cancer and that combined targeting of multiple components of the tumor ecosystem increases the efficacy of anti-cancer therapies. Our data highlight the role of microenvironmental, especially immune-related changes in driving breast tumor progression and emphasize the importance of studying pre-invasive tumors.
 Citation Format: Kornelia Polyak. DCIS to IDC progression - a key step of immune escape [abstract]. In: Proceedings of the AACR Special Conference on Rethinking DCIS: An Opportunity for Prevention?; 2022 Sep 8-11; Philadelphia, PA. Philadelphia (PA): AACR; Can Prev Res 2022;15(12 Suppl_1): Abstract nr IA035.