Breast cancer can metastasize to the lymph nodes near the tumor. Detecting this metastasis early is important because the cancer can spread further from there, which makes treatment significantly more difficult and worsens the prognosis. Luminescent nanoprobes can be used for labeling and tracking cancer cells. Persistent luminescence nanoparticles (PLNPs) are particularly useful because persistent luminescence can avoid interference from, e.g., background noise. The near-infrared (NIR) spectral range is well suited to these applications: It can avoid absorbance by living tissues and provide high sensitivity and deep penetration. So far, PLNPs had not been used to monitor the metastasis of breast cancer cells over time.
Qiao Sun, Zhen Li, Soochow University, Suzhou, China, and colleagues have tracked the metastasis of breast cancer using near-infrared long-persistent luminescence (NIR-PL) imaging. The team used Cr3+/Nd3+ codoped ZnGa2O4 nanoparticles, prepared by a hydrothermal method. The nanoparticles have an “afterglow” for over 15 days after 1 min excitation by UV light. The nanoparticles were used to label mouse breast cancer cells, which were injected into mice and tracked using NIR imaging.
The team found that the imaging was highly sensitive and allowed them to track cancer cell migration over several days. Since the nanoparticles contain heavy elements, they can also absorb X-rays. Thus, they could be used to enhance the effects of radiotherapy and help to kill metastasized cancer cells, which was confirmed in mouse experiments. According to the researchers, the probes have potential for the ultrasensitive detection, long-term monitoring, and therapy of tumors.
- Ultra-Sensitive Detection and Inhibition of the Metastasis of Breast Cancer Cells to Adjacent Lymph Nodes and Distant Organs by Using Long-Persistent Luminescence Nanoparticles,
Hanghang Liu, Feng Ren, Xingguo Zhou, Changqiu Ma, Tingting Wang, Hao Zhang, Qiao Sun, Zhen Li,
Anal. Chem. 2019.