Directly Evolved Nanovaccines Modulate Disrupted Circadian Rhythm and Enhance Cancer Immunotherapy

Abstract

The circadian rhythm, as a crucial endogenous biological oscillator, often undergoes disruptions, thus fostering severe immunosuppression within tumors. Here, this work develops directly evolved biovesicles as biological clock-modulated nanovaccines (Clock-NVs) to augment circadian clock gene expression and enhance cancer immunotherapy. These biovesicles act as bioreactors, transforming an unfavorable factor, ROS, into a beneficial circadian clock enhancer, oxygen. By targeting HIF-1α-BMAL1 axis, Clock-NVs restore the disrupted circadian rhythm within tumors. Upregulation of the core clock gene, BMAL1, initiates tumor cell death, enhances mitochondrial metabolism and antigen processing in dendritic cells to amplify antitumor immune responses. Clock-NVs effectively inhibit tumor growth, diminish metastasis, and demonstrate robust antitumor activity in a model of chemotherapy-resistant senescent tumors. Notably, Clock-NVs combined with adoptive T cell-based therapies achieve a 60% regression of primary tumors, while their use with anti-PD-L1 results in 100% inhibition of tumor recurrence. This strategy introduces nanovaccines designed to enhance temporal immunotherapy by precisely restoring the suppressed rhythm gene expression within tumors.

Keywords: bacterial vesicles; cancer immunotherapy; circadian rhythm; directed evolution; nanovaccines.