Dr. Fukamachi from Japan stays in AMC, Korea: Part5
A3 Foresight Program: Collaborative Research on the Role of Epigenetic Pathway in Gastric Carcinogenesis
Report of a visit to AMC in Korea (May 11 to May 21, 2011)
HIROSHI FUKAMACHI (Department of Molecular Oncology, Tokyo Medical and Dental University)
Host researcher
Prof. Se Jin Jang (Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine)
Summary
I visited again Prof. Se Jin Jang’s laboratory (Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul) in Korea to examine mice into which FACS-sorted cells were subcutaneously injected in my previous visits in last December and March. I also carried out additional experiments to identify gastric tumor-initiating cells using freshly dissected gastric tumor specimen. We found a successful case in which surface antigen-expressing cells formed tumors while non-expressing cells did not. Now we have found a total of four successful cases. We hope that we can soon get enough evidence suggesting that the cell surface antigen can be used for the identification of human gastric tumor-initiating cells. I deeply thank Prof. Se Jin Jang, Dr. Hyang Sook Seol and other members of AMC for giving me a chance to do experiment in a wonderful institute.
1. Background
As described in my previous report (“Dr. Fukamachi from Japan stays in AMC, Korea: Part 4”), we have been trying to identify gastric tumor-initiating cells in newly-dissected human gastric tumors. A purpose of my visit was to examine whether tumors were formed in mice into which FACS-sorted tumor cells were subcutaneously injected in our previous experiments. Another purpose was to carry out additional experiments to increase the number of cases and to obtain enough evidence to show that the antigen can be used for the identification of human gastric tumor-initiating cells, in collaboration with researchers in AMC including Professor Jang and Dr. Seol.
2. The experiment in AMC.
We found a successful case in which surface antigen-expressing cells formed tumors in mice into which FACS-sorted cells were injected in previous experiments while non-expressing cells did not. So far we have found three successful case in previous experiments. Thus the total number of successful cases was increased to four now. We hope that we can get more cases soon to obtain enough evidence showing that the antigen can be used for the identification of gastric tumor-initiating cells.
3. Discussion with the members of AMC
I discussed with the members of AMC how to develop our research after we will identify the marker of gastric tumor-initiating cells. Other useful markers may be identified by comparing gene expression profiles of tumor-initiating and non-tumor-initiating cells. It is also hoped that growth/differentiation control mechanisms may be disclosed by examining the profile. For the full development of the study, it would be very important to establish culture systems where tumor-initiating cells can propagate without loss of tumorigenicity. Preliminary experiments are now in progress to expand our research.
4. Acknowledgments
I deeply thank Professor Jang and Dr. Seol for their help and kindness during my stay in AMC. A skilled help by Ms. Hey-Jin Jeung, Asan Life Science Laboratory in analyzing cell surface antigens by FACS is also deeply acknowledged.
