Hydrogen Sulfide-Activatable Second Near-Infrared Fluorescent Nanoassemblies for Targeted Photothermal Cancer Therapy

Abstract

Near-infrared (NIR)-II fluorescence agents hold great promise for deep-tissue photothermal therapy (PTT) of cancers, which nevertheless remains restricted by the inherent nonspecificity and toxicity of PTT. In response to this challenge, we herein develop a hydrogen sulfide (H2S)-activatable nanostructured photothermal agent (Nano-PT) for site-specific NIR-II fluorescence-guided PTT of colorectal cancer (CRC). Our in vivo studies reveal that this theranostic Nano-PT probe is specifically activated in H2S-rich CRC tissues, whereas it is nonfunctional in normal tissues. Activation of Nano-PT not only emits NIR-II fluorescence with deeper tissue penetration ability than conventional fluorescent probes but also generates high NIR absorption resulting in efficient photothermal conversion under NIR laser irradiation. Importantly, we establish NIR-II imaging-guided PTT of CRC by applying the Nano-PT agent in tumor-bearing mice, which results in complete tumor regression with minimal nonspecific damages. Our studies thus shed light on the development of cancer biomarker-activated PTT for precision medicine.

Advanced Near‐Infrared Light for Monitoring and Modulating the Spatiotemporal Dynamics of Cell Functions in Living Systems

“…At present, the dual‐functional strategy has only been tested in few cases, such as cancer diagnosis and therapy. [ 67,66 ] Thereby, more strategies for simultaneous cell sensing and modulation should be designed and developed to meet the needs in different research fields, including regenerative medicine and neuroscience. In addition, further efforts are also needed to improve the sensitivity, specificity, and safety of the multifunctional light strategy to meet the needs of future clinical applications.…”

“…Recently, the dual‐functional strategies have been successfully applied in cancer diagnosis and therapy. [ 67,66 ]…”

Photoacoustic imaging and photothermal therapy in the second near-infrared window

“…The factors that affect the photothermal ablation of solid tumors are mainly the absorption of the PTT agent in the NIR region and the penetration depth of the tumor tissue. 65,[80][81][82][83][84] Currently, PTT in the NIR-II window has received increasing attention due to its merits of deep penetration ability, high MPE, and excellent ablation of tumor.…”

Surface Plasmon Resonance–Enhanced Photoacoustic Imaging and Photothermal Therapy of Endogenous H2S‐Triggered Au@Cu2O

“…In colon cancer, one of the specific physiological features is the highly expressed endogenous hydrogen sulfide (H 2 S) . Using endogenous H 2 S to trigger the photoacoustic imaging and photothermal therapy function of smart theranostics agents can effectively improve the diagnosis and treatment of colon cancer . For instance, Zhao and co‐workers developed an H 2 S‐triggered smart theranostics agent for NIR‐II fluorescence imaging–guided photothermal therapy .…”

“…Using endogenous H 2 S to trigger the photoacoustic imaging and photothermal therapy function of smart theranostics agents can effectively improve the diagnosis and treatment of colon cancer . For instance, Zhao and co‐workers developed an H 2 S‐triggered smart theranostics agent for NIR‐II fluorescence imaging–guided photothermal therapy . Using this H 2 S‐triggered smart agent, the colon cancer can be diagnosed accurately and completely regressed after photothermal therapy.…”