According to a new study published in the journal Science Immunology, the new cancer immunotherapy that can prevent the immune system from becoming tolerant of tumors, occurs in 30 percent of all cancer patients.
The research team was led by Wang Dangge from Shanghai Institute of Materia Medica under the Chinese Academy of Sciences and Fudan University, had developed a common immune checkpoint inhibitor in a nanoparticle formulation, which is highly tumor-specific.
The checkpoint inhibitor can be described as an anti-tumor drug. Its popularity has been increasing by every passing day. This drug is also capable of blocking proteins that keep immune T cells from killing cancer. However, this drug is used to target those immune system-suppressing proteins like PD-1 and PD-L1 often fails to reach deep-seated or metastatic tumors.
The team brought the nanoparticles together nanoparticles carrying PD-L1-targeting antibodies with a light-activated molecule. The molecule called photosensitiser can produce tumor-killing reactive oxygen species after encountering a protein abundant in tumors, according to the study.
In mouse models, local near-infrared radiation that activated the photosensitiser, along with the administration of antibodies-carrying nanoparticles, promoted the infiltration of cancer cell-killing T cells into the tumor site and made the tumors more sensitive to the checkpoint blockade.
This combination also helped the nanoparticles effectively suppress tumor growth and metastasis to the lung and lymph nodes, resulting in approximately 80 percent mouse survival over 70 days, compared to complete mouse death in 45 days in the group treated with only PD-L1 antibodies, according to the study.-