Regulating the Tumor Microbiome through Near-Infrared-III Light-Excited Photosynthesis

Tumor microbiomes are increasingly associated with the growth and metastasis of tumors. Exploring the regulation of the tumor microbiome through therapeutics is an area of interest in cancer therapy. In this study, the authors have investigated a biohybrid with 1550 nm light-excited photosynthetic ability to regulate the tumor microbiome. This system utilizes Er-based core-shell upconversion nanoparticles to arm microalga <i>Chlorella</i>, enabling the rapid evolution of <i>Chlorella</i> to perform oxygenic photosynthesis under 1550 nm light excitation. This biohybrid may alleviate hypoxia within the tumor microenvironment and induce significant changes in the tumor microbiome, ultimately resulting in marked inhibition of tumor growth. Benefiting from the strong tissue penetration ability of 1550 nm light, this biohybrid also exhibits clear inhibition of deep-seated tumors. The therapeutic efficacy of microbiome regulation is directly mediated by immune activation, converting "cold" tumors into "hot" tumors, which also leads to a long-lasting immune memory effect.