Chinese scientists develop tumor-specific anti-cancer therapy

WASHINGTON. KAZINFORM- Chinese scientists developed a combined tumor-killing therapy that can be activated specifically at tumor sites in mouse models of cancer, which is more effective than previous similar therapies, Xinhua reports.

The study published on Fridayin the journal Science Immunology described the new cancer immunotherapy thatcan prevent the immune system from becoming tolerant of tumors, which occurs in30 percent of all cancer patients.

A team led by Wang Dangge fromShanghai Institute of Materia Medica under the Chinese Academy of Sciences andFudan University developed a common immune checkpoint inhibitor in ananoparticle formulation, which is highly tumor-specific.

The checkpoint inhibitor is akind of increasingly popular anti-tumor drug. It can block proteins that keepimmune T cells from killing cancer. But the checkpoint inhibitor used to targetthose immune system-suppressing proteins like PD-1 and PD-L1 often fails toreach deep-seated or metastatic tumors.

Wang's team combined thenanoparticles carrying PD-L1-targeting antibodies with a light-activatedmolecule. The molecule called photosensitizer can produce tumor-killingreactive oxygen species after encountering a protein abundant in tumors,according to the study.

In mouse models, a localnear-infrared radiation that activated the photosensitizer, along with theadministration of antibodies-carrying nanoparticles, promoted the infiltrationof cancer cell-killing T cells into the tumor site and made the tumors moresensitive to the checkpoint blockade.

This combination also helpedthe nanoparticles effectively suppress tumor growth and metastasis to the lungand lymph nodes, resulting in approximately 80 percent mouse survival over 70days, compared to complete mouse death in 45 days in the group treated withonly PD-L1 antibodies, according to the study.