Photodynamic therapy (PDT) is a promising strategy against head and neck squamous cell carcinoma (HNSCC). In this study led by Chloé Thibaudeau et Alain Jung from the ONKO3T team, in collaboration with Professor Gilles GASSER, they investigated how different ruthenium(II)-based photosensitizers (PS) influence tumor cell death and immune response.
A surprising result
The two PS tested show strong phototoxicity and trigger several cell death pathways. However, their immune effects differ:
- The PS that induces strong apoptosis and significant endoplasmic reticulum (ER) stress paradoxically leads to immune tolerance.
- The one that causes more moderate ER stress generates a better antitumor immune response.
Rethinking immunogenicity in PDT
These observations reveal an inverse correlation between ER stress and immune efficacy, challenging the idea that apoptosis and high ER stress are essential for immunogenic cell death.
This work paves the way for a more sophisticated design of next-generation photosensitizers capable of optimizing both tumor destruction and immune system stimulation.
Congratulations to the team and its collaborators !
