OIST Prof. Tadashi Yamamoto is receiving the Tomizo Yoshida Award from The Japanese Cancer Association (JCA) for “outstanding achievement in the field of cancer research.” The largest association of its kind in Japan, the JCA grants five awards a year in different fields of cancer research. The award Prof. Yamamoto is receiving is classified as a basic science award named after the late Japanese cancer researcher Tomizo Yoshida (1903-1973). Before his arrival at OIST, Prof. Yamamoto worked at the University of Tokyo as well as the University’s Institute of Medical Science where he was director for 4 years. He now heads the Cell Signal Unit at OIST. The award will be given during the JCA's 73rd annual meeting from September 25 to 27.
The work that is being recognized is Prof. Yamamoto’s analysis of two specific proteins designated ERBB1 and ERBB2, which are encoded by the erbB family oncogenes. He first determined their genetic structures and further analyzed how the altered expression of these proteins affects tumor growth and survival rates in cancer patients.
“In the beginning the research used chickens as a model organism and characterized the erbB oncogene, a gene that induces the transformation of normal cells into cancerous cells. Later, it turned out that the erbB oncogene induces tumors not only in chickens, but the two related proteins, ERBB1 and ERBB2, contribute to development of human tumors,” says Prof. Yamamoto. “It wasn’t very obvious that the proteins were associated with so many types of cancers. But after much successful research we know now that these two proteins are contributing factors to many types of cancers.”
The function of ERBB1 is to receive extracellular signals, specifically a molecule called Epidermal Growth Factor, or EGF. The molecule is responsible for signaling the cell to proliferate or multiply. ERBB2 is highly related to ERBB1 but does not receive EGF or any other known signals. Overexpression and mutation of ERBB1 and overexpression of the ERBB2 protein can cause intracellular activities for cell proliferation to begin even without the proteins having received signals to do so. If this occurs, it leads to unregulated proliferation of cells and cancers are eventually formed.
Prof. Yamamoto’s current work at OIST is a continuation of the research he is being recognized for. He now studies how the ERBB family of receptor proteins, ERBB1 and ERBB2, transmits signals within individual cells. The interaction between the ERBB family of proteins and gene expression machinery, particularly proteins such as CCR4-NOT, is an important piece of the puzzle in understanding how unusual expression of ERBB family proteins cause unchecked cell proliferation and tumor development. Prof. Yamamoto says that the CCR4-NOT protein complex, which initiates breakdown of mRNAs within cells, is one of the important next steps after protein receptors in understanding the intracellular signaling for cell proliferation.
Prof. Yamamoto showed a picture of a road with two different paths, one labeled drug development and the other labeled basic research, Prof. Yamamoto commented, “… at my age many people feel they should make a choice. One path is to try developing medicine or application and the other is to dig for more knowledge. And digging for more knowledge is what I am doing here.”
By Sean To
