A NIR-II Fluorophores for Multiple Myeloma Imaging and Photodynamic Therapy

Background: Multiple myeloma is a hematological malignant disease in which clonal plasma cells proliferate abnormally. NIR-II fluorophores have great application prospects for cancer treatment.

Methods: Multiple detection techniques were used to evaluate effect and mechanisms of the novel small-molecule NIR-II fluorophores probe on multiple myeloma cells in vitro experiment. In vivo MM.1S Luc+ B-NSG mouse model was built to assess the role of probe in multiple myeloma treatment.

Results: The novel small-molecule NIR-II fluorophores probe shown high affinity with multiple myeloma cells and specific myeloma imaging in vivo. More importantly, the probe could effectively induce tumor death with 808 nm laser irradiation in a dose-dependent manner. Further, Confocal found that the probe was mainly distributed in mitochondria and significantly reduced the mitochondrial membrane potential with laser irradiation. Moreover, Reactive Oxygen Species (ROS) level was notably increased and the up-regulation expression of cleaved poly ADP-ribose polymerase (PARP) was detected after treated with the probe and laser irradiation. Consistent with the previous results, the disease was alleviated obviously in probe laser-treated group.

Conclusions: Our work confirm for the first time that the specific imaging and remarkable photodynamic therapy (PDT) effect of a novel NIR-II fluorophores probe to multiple myeloma. It provides the foundation for application of NIR-II fluorophores from solid tumor to non-solid tumor.