Glycyrrhetinic acid modified chlorambucil prodrug for hepatocellular carcinoma treatment based on DNA replication and tumor microenvironment

Chlorambucil (CLB) is widely used in the treatment of solid tumors. However, CLB has poor water solubility, short half-life and side effects such as leucopenia and thrombocytopenia, in addition to the inhibition of tumor immune microenvironment. In our study, chlorambucil-chitosan (CLB-CS) prodrug micelles were successfully prepared, and glycyrrhetinic acid (GA) was selected, which could improve the immunosuppressive microenvironment and actively targeted liver cancer cells. At the tumor site, CLB blocked the cell cycle and promoted apoptosis. In addition, GA improved the tumor microenvironment by increasing the proportion of CD4+T and CD8+T cells at the tumor site, and promoting the differentiation of CD4+T cells into Th1 cells, thereby reducing the proportion of Treg and Th2 cell subsets, so as to offset the adverse factors of CLB against tumor immunity. By interfering with DNA replication and modulating the tumor microenvironment, GA/CLB-CS micelles enabled the effective treatment of liver cancer.