2010년 1월 14일자 <이코노미스트>지에 실린 “중국의 줄기세포”입니다.
이코노미스트 Jan 14th 2010 | Beijing http://www.economist.com/node/15268869 . Illustration by David Simonds IN THE West, and particularly in America, the phrase “stem cell” has acquired a bad reputation. Stem cells are associated, in the minds of many, with the destruction of human embryos, the cloning of human beings and the Frankenstein-like creation of spare body parts. Add in the strange case of Hwang Woo-suk, a South Korean researcher who announced, to great acclaim, that he had succeeded in cloning human embryos and was then exposed as a fraud, and you have a field in which many researchers understandably fear to tread.
Not Chinese researchers, though. A Confucian rejection of the idea that embryos are in any meaningful sense human beings (a view shared by many Koreans), together with the possibility of stealing a march on the diffident West, has stimulated a lot of research into stem cells in China. And not only research. Chinese clinics have moved with what many foreign scientists regard as indecent haste into the offering of therapies. Patients from around the world fly in for the treatment of conditions ranging from autism to spinal-cord injury—treatments that are rarely based on science that would pass muster with the authorities in most rich countries, and are often outright frauds.
A stem cell is one that, when it divides, has the potential to generate specialised cell types through one daughter line while the other daughter retains the property of “stemness”. Some stem cells, known as pluripotent cells, can generate several different cell types. The pluripotent cells found in embryos, for example, can turn into any one of the 220 or so cell types of which a human body is formed.
This is a rich vein for medical science to mine, and that is what Chinese scientists are doing. It is part of a field that has come to be known as “regenerative medicine” and a study just published in the journal of that name, by Halla Thorsteinsdottir of the McLaughlin Rotman Centre for Global Health in Toronto and her colleagues, found that 1,116 stem-cell papers published in international peer-reviewed journals in 2008 came from China, making it the fifth-largest source of such papers, after the United States, Germany, Japan and Britain. If the cowboys can be reined in, then, China may show in the case of stem cells that it is the peer of established scientific powers.
A potent mix
Dr Thorsteinsdottir’s study did more than just analyse publications on stem cells, however. It attempted to paint a comprehensive picture of the field. The researchers visited Chinese universities, hospitals, biotechnology companies and in-vitro fertilisation clinics, as well as carrying out face-to-face interviews with 47 experts from a range of organisations, including ministries and funding agencies.
Dr Thorsteinsdottir found that though many hospitals are making a profit from offering unproven therapies, a number of proper clinical trials are also being conducted using stem cells, for conditions such as heart-muscle damage, ischemia (restricted blood supply) of the limbs, liver disease and neurological disorders. These include a multi-centre trial organised by the China Spinal Cord Injury Network, a consortium of over two dozen centres in mainland China, Hong Kong and Taiwan, to test whether a combination of lithium and transplants of stem cells from umbilical-cord blood could lead to improvements in patients with spinal-cord injury.
Moreover, last year researchers at the Chinese Academy of Sciences, in Beijing, and Shanghai Jiao Tong University dispelled some of the voodoo surrounding stem cells by producing fertile mice from inducible pluripotent cells. An inducible pluripotent cell is one derived from a body cell (skin, for example) that has been made pluripotent by chemical treatment, rather than having been extracted from an embryo. Besides saving embryos, that means (if the same trick can be repeated in humans) that replacement organs might be grown from a patient’s own tissues.
This is all very encouraging. China’s health ministry has, however, turned a blind eye to the unauthorised stem-cell therapies offered by hundreds of hospitals under its jurisdiction. One company in particular, Beike Biotechnology in Shenzhen, Guangdong province, is notorious for its internet claims and marketing efforts in countries around the world. It claims to supply stem cells to a network of more than two dozen hospitals in China and one in Thailand for treating myriad conditions at a cost of about $20,000 a pop.
Beike says it has treated over 6,000 patients, but it has yet to publish any papers in internationally recognised, peer-reviewed journals. Yet it seems to have powerful friends. It claims to have received funding from the China State National Fund and Shenzhen municipality. It also claims to have members of the Chinese Academy of Sciences and Chinese Academy of Engineering on its scientific advisory board. And Xinhua, China’s state press agency, calls Beike “a global leader in stem-cell research and treatment through evidence-based medicine”.
Last May, in a bid to clean up the field, the health ministry announced new regulations on those medical technologies—including stem-cell therapies—that have yet to be proven to be safe and effective or are considered ethically controversial. Within six months of the regulations coming into effect, hospitals around the country were supposed either to stop providing unproven therapies or to apply to the ministry for approval. Violations could lead to fines and the suspension of technology and treatment licences. For serious breaches, hospitals and clinics could lose their permits to practise medicine—in theory.
Time to regenerate
How the practice will work out is, however, a different question. Many observers fear that the enforcement of the new regulations will be weak. Such ministerial fiats have questionable legal authority and procedures for monitoring and ensuring compliance are often opaque. Moreover, at 3,000 yuan ($430), the fines for breaching the regulations are ridiculously low and, with the possible exception of small private clinics, it is unlikely that hospitals would lose their general permits to practise medicine just for offering unproven stem-cell therapies. It is little surprise, then, that eight months after the regulations were enacted, some companies and hospitals continue to advertise and offer unproven stem-cell therapies.
Moreover, Dr Thorsteinsdottir’s team found that China’s push for clinical applications, though admirable in one sense, comes at a cost to basic research. This is a concern not just in the field of stem-cell science. Of China’s research-and-development expenditure, 78% is reserved for product development, with another 16.8% for applied research. Only 5.2% is allocated to basic research, compared with 13-19% in Japan, South Korea and the United States.
Dr Thorsteinsdottir also noted that regenerative medicine in China is a matter of national prestige. Some researchers in China believe that this is an area in which their country is likely to produce a Nobel-prize laureate. They should, perhaps, be reminded that nationalism was the force that propelled Dr Hwang to stardom before reality destroyed him. For nature, unlike people, cannot in the end be cheated.
