BBI Contributing Writer

While many pioneering cancer research studies are being conducted in Japan, frustration is mounting among researchers whose findings have not yet been implemented in clinical sites by physicians. Their concerns, expressed during October's 59th annual meeting of the Japanese Cancer Association, were heightened by hearing that five-year survival rates among cancer patients have improved impressively in the U.S.

Some presenters at the cancer group's meeting ironically pointed out that the increasing number of cancer deaths in Japan is largely attributed to the thriving westernization of the Japanese life style, as if to admit that they have no effective remedies other than reviving healthier old Japanese dietary habits.

Yusuke Nakamura, MD, of the Human Genome Analysis Center, said, "while human genomic codes are expected to be completely decoded by 2003, another three to five years, or even more time will be required to decipher the functions of all the genomes." He predicted that cancer research in the "post-genome sequence" will follow two mainstream courses: 1) systematic decoding of genetic expressions, and 2) systematic analysis of genetic polymorphism.

Nakamura said that emergence of innovative technologies such as DNA microarrays is allowing a comprehensive analysis of manifestational changes of genes numbering tens of thousands. He also noted that high-speed systematic analysis of genetic polymorphism such as single nucleotide polymorphism is rapidly materializing. "These [studies] will enable analysis of the genesis, development and growth of cancer at molecular levels and individual diagnosis of cancer, leading to side effect-free, tailor-made therapy for each patient."

A pathologist asked how the current cumbersome steps for decoding genomes are supposed to be related to pathology, prevention and treatment. Nakamura responded, "All we have today is as a result of decades of research, and likewise, our achievements today will be endorsing tomorrow's treatments." Also stemming from Nakamura's analytical methodology, another question was raised by a meeting participant expressing concern that there must be certain disparities between genes depending on sites of sampling with regard to genetic functions so that samplings may have to be made from several sites. He affirmed his conviction that samplings from two different sites will be sufficiently representative of a genetic make up of a particular patient.

In Japan, stomach and cervical cancers previously were the most prevalent types of cancers. More recently, cancers of breast, abdomen, lung and liver are increasing. Emphasis on mass screening is the only current means of preventive medicine, while relatively minor national efforts have been directed toward primary preventive measures such as promoting smoking cessation or healthier dietary practice – the effect of which is demonstrated in other industrialized nations in the form of reduced incidence of lung cancer, etc. With numerous presenters making the point that Japan is in need of aggressive promotion through the mass media emphasizing reduction of exposure to harmful substances, the message appears to be that all these research results may not soon be directly linked to therapies.

Despite the fact that the period for research studies on removing Helicobacter pylori and preventive measures for the genesis of stomach cancer as a part of the new, 10-year, anti-cancer project had been postponed for two years, the patient registrations had to be discontinued since enrollment fell far short of the initially targeted number (3,500 vs. 750), which led to an outcry for rectifying insufficiency in organizing an infrastructure required for conducting clinical intervention trials in Japan.

While many individual studies done in Japan excel in quality, each of these research results remains an isolated episode, lacking a mechanism for linking those achievements together. That is a growing question among academic societies in Japan. There were suggestions at the conference for division of research activities along internationally shared themes.

Interestingly, 99.75% of all sign-ups for presentations at the association's meeting at Pacifico Yokohama were made via the Internet, while only 0.25% presented in a typewritten form.

Technologies available from Tsukuba

The Institute of Tsukuba Liaison (ITL), the technology liaison of the University of Tsukuba (Tsukuba, Japan), reports that a new experimental animal has been developed by Dr. Jun-Ichi Hayashi, professor at the university, for which patent application has been filed by ITL. The new experimental animals are mice specialized by the partial deletion mutation in mitochondrial DNA. The so-called "mitochondrial DNA knock-out mice" are born healthy but suffer from some sicknesses in the course of their lives, but only when the percentage of the mutated mitochondrial DNA is over 80%.

The scientific features of this technology are reported in the Sept. 28, 2000, edition of Nature Genetics. The experimental animal will be a tool for the research of several geriatric diseases such as cardiomyopathy, augenphtise or nephropathy. Contact: Dr. Junji Seki, licensing advisor of ITL. E-mail: mail@tliaison.com, Tel: 81-298-50-0195, Fax: 81-298-61-1189.