GLOSSARY

1 Immunotherapy

This is a method of damaging cancer cells by strengthening the immune system, and is particularly famous for the method discovered by Dr. Tasuku Honjo and others, which led to the Nobel Prize. This is a therapy to fight cancer by boosting one’s own immunity by covering the receptor named PD-1, which suppresses immunity, and Dr. Honjo and his colleagues discovered nivolumab as the protein that plays the role of the cover. Nivolumab was launched in 2014 under the brand name of Opdivo by Ono Pharmaceutical Co.

2 Photoimmunotherapy

This is a method of cancer treatment invented by Dr. Hisataka Kobayashi and his colleagues at the National Cancer Institute (NCI) of the U.S. National Institutes of Health (NIH), and is exclusively manufactured and sold by Rakuten (Chairman and President Hiroshi Mikitani) under license from NIH. Cetuximab (EGFR antibody) is used as the “Hippocampus” and IRDye® 700DX, a photosensitive substance, is used as the “weapon.

3 BNCT (Boron Neutron Capture Therapy)

BNCT, Boron Neutron Capture Therapy

This is a cancer treatment method that selectively damages cancer cells by irradiating neutrons and using alpha and lithium rays generated by nuclear reactions with boron-10, which has a mass of 10. In 2012, Stellar Pharma and Sumitomo Heavy Industries collaborated with the Kyoto University Research Reactor Institute to launch the world’s first accelerator-based clinical trial, and in 2016, the Brain and Nervous System Research Institute in Fukushima Prefecture established the South-Northeast BNCT Research Center and began clinical trials for brain tumors and head and neck cancer using the accelerator- based BNCT system manufactured by Sumitomo Heavy Industries. In 2020, the insurance coverage of BNCT for “unresectable locally advanced or locally recurrent head and neck cancer” started. In April 2021, Stellar Pharma was listed on the Mothers market.

4 Trojan Horse

Trojan Horse is a device used by the Greeks to bring about the fall of Troy during the Trojan War in Greek mythology. It was made of wood so that people could hide inside. According to the Aeneid by Virgil, after a ten-year siege, the Greeks, under the orders of Odysseus, built a huge wooden horse, hid their troops, including Odysseus himself, inside, and brought them into the city of Troy. Here, the “Trojan Horse” metaphorically refers to the strategy of secretly drawing “weapons” into the target.

5 Glucose transporter

Glucose (D-glucose) is the most basic source of energy or carbon, and is taken up and used by almost all living organisms in their cells. In the case of mammalian cells, D-glucose must pass through the cell membrane, which consists of a lipid bilayer, to enter the cell, but because D-glucose is a water-soluble molecule of a certain size and shape, it cannot freely pass through the cell membrane. The glucose transporter is a water-soluble molecule of a certain size and shape. Glucose transporters are representative of the transmembrane proteins (also called membrane transport proteins or carrier proteins) that mediate this process, i.e., the transport of D-glucose into the cell (also called membrane transport) in mammalian cells, and the GLUT family is well known.

6 Channel-like proteins

Channel is a type of transmembrane protein, and ion channels such as sodium ion channels and potassium ion channels are typical examples. The difference between the transporter and the channel is as follows: In the transporter, the binding of a substrate (in the case of a glucose transporter, the substrate is D-glucose) to the transporting protein causes the protein to undergo a conformational change from a state in which the opening and substrate binding sites are directed to the outside of the cell membrane to a state in which the opening and substrate binding sites are directed to the inside of the cell membrane. As a result, the substrate bound to the substrate-binding site from the outside of the cell membrane leaves the protein and moves to the inside of the cell membrane, resulting in the transport of the substrate from the outside to the inside of the cell membrane (carrier). This is similar to a game of musical chairs, where if the chair (i.e., binding site) is occupied, the substrate must wait outside the chair. In contrast, the channel is a protein that does not have a substrate binding site, but instead has a mechanism called a gate that interacts with the substrate and can transport the substrate much faster than a transporter. The term “channel-like protein” refers to proteins that have a transport mode similar to that of channels.