Hydrogel-embedded precision-cut lung slices support ex vivo culture of in vivo-induced premalignant lung lesions

Lung cancer is the leading cause of global cancer death and prevention strategies are key to reducing mortality. Medical prevention may have a larger impact than treatment on mortality by targeting high-risk populations and reducing their lung cancer risk. Premalignant lesions (PMLs) that can be intercepted by prevention agents are difficult to study in humans but easily accessible in murine preclinical carcinogenesis studies. Precision-cut lung slices (PCLS) are underutilized as an ex vivo model for lung cancer studies due to limited culture time. Embedding PCLS within bioengineered hydrogels extends PCLS viability and functionality for up to six weeks. Here, we embedded PCLS generated from urethane-induced murine PMLs in cell-degradable and non-degradable hydrogels to study viability and activity of the tissues over six weeks. PMLs in hydrogel-embedded PCLS maintained viability, gene expression, and proliferation. Treatment of hydrogel-embedded PCLS containing urethane-induced PMLs with iloprost, a known lung cancer prevention agent, recapitulated in vivo gene expression and activity. These studies also showed that iloprost reduced proliferation and PML size in hydrogel-embedded PCLS, with some differences based on hydrogel formulation and suggested that hydrogel-embedded PCLS models may support long-term culture of in vivo generated PMLs to improve preclinical studies of lung cancer and prevention agents.