Degradable poly(apigenin) polymer inhibits tumor cell adhesion to vascular endothelial cells

Cancer and the inflammatory system share a complex intertwined relationship. For instance, in response to an injury or stress, vascular endothelial cells will express cell adhesion molecules as a means of recruiting leukocytes. However, circulating tumor cells (CTCs) have been shown to highjack this expression for the adhesion and invasion during the metastatic cascade. As such, the initiation of endothelial cell inflammation, either by surgical procedures (cancer resection) or chemotherapy can inadvertently increase the metastatic potential of CTCs. Yet, systemic delivery of anti-inflammatories, which weaken the entire immune system, may not be preferred in some treatment settings. In this work, we demonstrate that a long-term releasing flavone-based polymer and subsequent nanoparticle delivery system can inhibit tumor cell adhesion, through the suppression of endothelial cell adhesion molecule expression. The degradation of a this anti-inflammatory polymer provides longer term, localized release profile of active therapeutic drug in nanoparticle form as compared with that of the free drug, permitting more targeted anti-metastatic therapies.