Lovastatin/SN38 co-loaded liposomes amplified ICB therapeutic effect via remodeling the immunologically-cold colon tumor and synergized stimulation of cGAS-STING pathway.

Abstract

Current immune checkpoint blockade (ICB) immunotherapeutics have revolutionized cancer treatment. However, many cancers especially the "immunologically cold" tumors, do not respond to ICB, prompting the search for additional strategies to achieve durable responses. The cGAS-STING pathway, as an essential immune response pathway, has been demonstrated for a potent target to sensitize ICB immunotherapy. However, the low efficiency of conventional STING agonists limits their clinical application. Recent studies have shown that DNA topoisomerase I (TOPI) inhibitor chemodrug SN38 can activate the cGAS-STING pathway and induce an immune response through DNA damage, while the traditional statins medication lovastatin was found to inhibit DNA damage repair, which may in turn upregulate the damaged DNA level. Herein, we have developed a liposomal carrier co-loaded with SN38 and lovastatin (SL@Lip), which can be accumulated in tumors and efficiently released SN38 and lovastatin, addressing the problem of weak solubility of these two drugs. Importantly, lovastatin can increase DNA damage and enhance the activation of cGAS-STING pathway, coordinating with SN38 chemotherapy and exhibiting the enhanced combinational immunotherapy of PD-1 antibody by remodeling the tumor microenvironment in mouse colorectal cancer of both subcutaneous and orthotopic xenograft models. Overall, this study demonstrates that lovastatin-assisted cGAS-STING stimulation mediated by liposomal delivery system significantly strengthened both chemotherapy and immunotherapy of colorectal cancer, providing a clinically translational strategy for combinational ICB therapy in the "immunologically cold" tumors.

• Authors: Yi Yang, Jialong Qi, Jialin Hu, You Zhou, Jiena Zheng, Wenxia Deng, Muhammad Inam, Jiaxin Guo, Yongyi Xie, Yuan Li, Chuanshan Xu, Wei Deng, Wenjie Chen
• Journal: Cancer letters (Cancer Lett) Vol. 588 Pg. 216765 (Apr 28 2024) ISSN: 1872-7980 [Electronic] Ireland
• PMID: 38408604 (Publication Type: Journal Article)
• Copyright: Copyright © 2024 Elsevier B.V. All rights reserved.

Chemical References

• Lovastatin
• Immune Checkpoint Inhibitors
• Liposomes
• Hydroxymethylglutaryl-CoA Reductase Inhibitors

Topics

• Humans
• Animals
• Mice
• Lovastatin (pharmacology)
• Immune Checkpoint Inhibitors
• Liposomes
• Colonic Neoplasms (drug therapy)
• Hydroxymethylglutaryl-CoA Reductase Inhibitors
• Immunotherapy
• Neoplasms
• Tumor Microenvironment