Kazunori Kataoka, Director of Nanomedical Innovation Center (Specially Appointed Professor, Policy Vision Research Center, University of Tokyo), Senior Researcher Yone Peng, Professor Nobuhiro Nishiyama, Tokyo Institute of Technology, Ichio Aoki, Team Leader, Quantum Science and Technology Research and Development Organization, etc. The company announced that it has developed a nanomachine contrasting agent that can visualize malignancy and "hypoxic region in tumor" with high sensitivity by MRI in a microenvironment.
Currently, MRI is widely used in Japan as a magnetic diagnostic imaging device that does not use radiation.Especially in the diagnosis of cancer, it is said that there is a strong demand in recent years for the development of safe and highly functional contrast media as well as the performance improvement of the MRI device itself.
The research team has succeeded in developing a nanomachine contrast agent in which a manganese contrast agent with an MRI contrast effect is mounted on "calcium phosphate nanoparticles".This contrast agent is covered with an outer shell that is safe for living organisms and dissolves in response to the low pH environment of cancer tissue.It is said that the manganese contrast agent released from the nanoparticles has the property of amplifying the MRI signal about 7 times by binding to the protein of the cancer tissue.In addition, it was found that the part where the signal increases remarkably in the central part of the cancer is the hypoxic region showing resistance to anticancer drugs and radiotherapy, so this region can be visualized with high sensitivity and high accuracy.This time, he succeeded in detecting microscopic colorectal cancer with a diameter of only 1.5 mm that had metastasized to the liver with high sensitivity, and showed superior detection power compared to existing MRI contrast agents.
This nanomachine contrast agent is a relatively inexpensive low-field MRI device that is the most widely used in clinical practice, and is said to be extremely useful because it shows particularly excellent signal elevation.In addition, it is expected to be applied to early detection of cancer and metastasis, prediction of therapeutic effect and judgment of therapeutic effect, and it is expected to realize highly reliable cancer diagnosis and treatment that will not be overlooked in the future.