Unzippable Siamese Nanoparticles for Programmed Two-Stage Cancer Immunotherapy

Area of Science:

• Oncology
• Immunology
• Nanotechnology
• Drug Delivery

Background:

• Epigenetic drugs (epi-drugs) show promise in cancer therapy by inducing cell death and immune responses.
• Limited success in solid tumors is partly due to the induction of immunosuppressive myeloid-derived suppressor cells (MDSCs).

Purpose of the Study:

• To develop a targeted nanoparticle system for dual delivery of an epi-drug and an MDSC inhibitor.
• To overcome the immunosuppressive tumor microenvironment and enhance anti-tumor immunity.

Main Methods:

• Development of dissociable Siamese nanoparticles (SIANPs) for targeted delivery.
• Assembly of SIANPs via DNA annealing and triggered detachment in the tumor microenvironment.
• Co-delivery of epi-drug CM-272 to tumor cells and Ibrutinib to MDSCs.

Main Results:

• SIANPs induced immunogenic cell death in tumor cells and restrained MDSC immunosuppression.
• Enhanced dendritic cell maturation and CD8+ T cell activation were observed.
• The approach overcame resistance to immune checkpoint blockade therapy.

Conclusions:

• Dissociable nanoparticles offer a dual-targeting strategy for cancer immunotherapy.
• This approach enhances anti-tumor immunity and overcomes resistance to existing therapies.
• Paves a new way for employing epi-drugs in cancer immunotherapy.