vol.37 Department of Stem Cell Biology

Professor Kondo’s research group is studying how changes in stem cells and precursor cells determine canceration and aging and lead to the onset of diseases. Among these studies, Professor Kondo is paying attention to membrane proteins, which are one of the genes specific to glioblastoma (the most malignant brain tumor) stem cells, and to humoral factors involved in the aging of neural precursor cells.

The Department of Stem Cell Biology is now conducting research focusing on the following three themes: (1) Analysis of brain tumor stem cells and development of new therapeutic methods, (2) Analysis of new genes related to Alzheimer’s disease and development of therapeutic methods, (3) Analysis of new genes related to aging. In each case, they are analyzing how membrane proteins and humoral factors are involved, which has led to developments such as obtaining patents and joint research with domestic and overseas venture companies.

“Why are you getting old? I think that research to find the answer with the goal of scientifically clarifying what everyone is wondering about is a self-expression as a researcher, and it is a real thrill. It would be even more fun if the results lead to opening up unknown areas,” the professor says.

There are two types of fat cells, white fat and brown fat, in the body of humans and mice. It is said that people with high brown fat activity have good metabolic efficiency and find it hard to gain weight. Lecturer Youlee Son focuses on this brown fat and is studying the mechanism of aging and obesity.

“To activate brown fat, it is good to take actions that generate heat in the body such as exercise, and it is said that the most effective is cold stimulation. However, using cold stimulation as a treatment for obesity is not very realistic. In our research, we are finding genes that are expressed only in brown fat and are looking for ways to enhance or diminish their function,” Lecturer Youlee Son says.

In the experiments by Lecturer Youlee Son, et al., when a gene specifically expressed in brown fat was selected as a candidate and a high-fat diet was given to normal mice and mice in which the gene was completely disabled, the mice in which the gene was disabled did not gain weight. Currently, they are working on elucidating the molecular mechanism of genes.

Assistant Professor Shigeru Hashimoto, who is working on the analysis of brain tumor stem cells and the development of new therapies, is working to elucidate the action mechanism that is a molecular target for brain tumors using a molecular mechanism based on the characterization of stem cells (investigation of the molecular mechanism of how the cells acquire specific phenotypes) of glioblastoma, which is the most malignant of brain tumors.

Cancer stem cells have the property of self-renewing and differentiating into various cancer cells. Assistant Professor Hashimoto’s research group collected the cells of malignant tumors in the brains of mice and compared the differences in gene expression between those with and without cancer stem cellularity. They are conducting research to identify gene expression peculiar to cancer stem cells and to develop diagnostic and therapeutic methods targeting the proteins and metabolites that cause the gene expression.

“This laboratory has the advantage of having advanced know-how on stem cell characterization based on Professor Kondo’s achievements, which is highly likely to lead to the development of drug discovery and therapeutic methods,” Assistant Professor Hashimoto says.

Assistant Professor Naoto Oikawa, who is conducting research on new genes related to Alzheimer’s disease, aims to elucidate the relationship between proteins whose expression increases with aging and dementia represented by Alzheimer’s disease. “Some brain cells show changes in protein expression with age. This was discovered in this laboratory. As we continue to analyze it, we have found that what is happening in the brains of patients with Alzheimer’s disease is likely to be related to the protein,” Assistant Professor Oikawa says. Assistant Professor Oikawa’s research group is constructing an experimental system that induces aging in the nerve cells of the brain, and is conducting research on the relationship between factors thought to be involved in aging and neurological disorders.