Photoimmunotherapy is a treatment method that uses a drug that combines an antibody that recognizes cancer cells with a photosensitizer (compound that is activated by light). It is a method that kills cancer cells by causing a chemical reaction in the agent to generate a cell-damaging substance (singlet oxygen).It is being developed as a new treatment method that can treat even advanced cancers that are difficult to remove without surgery, and that can only damage cancer cells where photosensitizers have accumulated, without damaging normal cells and tissues. .

　However, since near-infrared rays have a limited range within the human body, even if the tumor appears to have disappeared with the naked eye after treatment, some cancer cells may still remain and may recur. It was said that it was an issue.

　Therefore, this group has developed a highly effective therapeutic drug that combines a new photoactivator Ax-SiPc that can produce more singlet oxygen than conventional drugs with an antibody mimetic drug that specifically binds to antigens on the surface of tumor cells. Newly developed "FL2".

　When 10 mice transplanted with human breast cancer cells were treated using this, the tumors in all mice decreased rapidly after the first treatment, but 1% (30 mice) after 5 days. recurrence was observed inThen, after the recurrent tumor had grown larger (5 days after treatment), a second treatment was performed. It is said that he discovered that the cells of

　In other words, repeated administration of FL2 induces tumor immunity, suggesting that it may be effective in eradicating light-accessible skin tumors.The results of this research are expected to lead to the establishment of an epoch-making treatment that cures cancer without surgery.

Paper information:[Cancer Science] Pathological complete remission of relapsed tumor by photo-activating antibody–mimetic drug conjugate treatment