Synthetic Genetic Circuits for Cancer Immunotherapy

Abstract

Immunotherapy has achieved remarkable success in certain types of cancer, primarily hematological malignancies. However, its broader application has been hindered by a lack of tumor-specific antigens, systematic toxicity, and tumor-mediated immunosuppression. To overcome these challenges, synthetic genetic circuits (in brief, gene circuits) for cancer immunotherapy have been developed, which sense intracellular tumor signatures and elicit immune responses locally at the tumor site. Although the gene circuit approach has demonstrated promising efficacy, it still requires design and optimization for each cancer type. Moreover, due to various challenges, such as tumor heterogeneity and low delivery efficiency, the generalizability and efficacy of gene circuits still need to be improved. Therefore, this thesis optimizes different components of the cancer immunotherapy gene circuits and develops gene circuits targeting shared features of tumors. It is demonstrated that the latest gene circuits can achieve 1000-fold tumor specificity in vitro. A random promoter and a miRNA sensor library have also been established to expand the sensor repertoire available for the gene circuits. The gene circuit components and building pipelines developed in this study will be valuable not only for cancer treatment but also for treating other immunological disorders and diseases that involve aberrant TF or miRNA activities, such as autoimmune, neurodegenerative, and metabolic diseases. These platforms and pipelines could also serve as tools for basic biological research.