Nature Magazine 7250

AUTHORS Vol 459 | Issue no. 7250 | 25 June 2009 Abstractions MAKING THE PAPER LAST AUTHOR Dewashish Upadhyay People with Down’s syndrome, a disorder caused by having an Ancient rocks bear traces of extra copy of all or part of Earth’s tumultuous early years. chromosome 21, tend to have lower-than-average Cratons are the oldest, most stable parts of cognitive ability and Earth’s crust, and as such hold clues to Earth’s several characteristic physical features, as early evolution. Dewashish Upadhyay, a geo- well as a shorter lifespan. But, much to the chemist now at the Indian Institute of Tech- puzzlement of scientists, they are also less nology in Kharagpur, analysed the make-up likely to develop solid cancers — tumours that of isotopes in rocks from India’s Bastar craton early, geochemically tumultuous time. form in tissues or organs. Theories proposed and found that some of the rocks carry the sig- 142Nd is produced by the α-decay of samar- to explain this phenomenon include the nature of a differentiation event — the separa- ium-146, a now-extinct nuclide. Major geo- possibility that many individuals with Down’s syndrome die too early for such cancers tion of materials with different geochemical chemical differentiation events, such as the to emerge, or that they aren’t exposed to properties. This event must have taken place formation and crystallization of a magma ocean, environmental risk factors or to stress and during the first 400 million years of Earth’s could have fractionated samarium and neo- pressure, which have been linked to cancer. history, possibly when a magma ‘ocean’ cover- dymium, producing reservoirs with contrast- 142 But Sandra Ryeom at the Children’s Hospital ing the planet solidified. ing Nd compositions. Because the Greenland 142 Boston in Massachusetts and her team have The area encompassing the Bastar craton reservoirs were rich in Nd, researchers started discovered a biological basis for the protective and the neighbouring Eastern Ghats Granulite to look for a complementary reservoir with a effect of the disorder. Using mouse models, Belt of southeastern India is rich in old rocks. 142Nd deficit. And Upashyay wondered whether they found that the low solid-cancer rate is The presence of alkaline igneous rock — a type his rocks, rich as they were in incompatible ele- attributable at least in part to an extra copy of of rock derived from Earth’s mantle — marks ments, could have come from such a reservoir. a gene whose product blocks the formation the location where the Indian subcontinent To test his suspicions, he needed to measure of new blood vessels — a process called split apart from another land mass 1.4 billion the ratio of 142Nd to 144Nd, a naturally occur- angiogenesis — that typically feed tumours years ago and then collided with East Antarc- ring radioisotope that serves as a reference (see page 1126). Ryeom tells Nature more. tica 1.1 billion years ago. point. “If we can measure variation in 142Nd, For his graduate project at the University of it implies there was some sort of a differentia- How does this gene block angiogenesis? Bonn in Germany, Upadhyay made extended tion event that fractionated samarium from We learned that DSCR1, a protein encoded by visits to the craton to collect samples and neodymium,” Upadhyay says. a gene on chromosome 21, suppresses one map the area. His initial analyses determined Upadhyay got the opportunity to do this of the signals needed for new blood vessels that the rocks were enriched in what he calls analysis as a postdoc in Klaus Mezger’s labo- to grow. When tumours are starting to form, ‘incompatible elements’ — elements that prefer ratory at the University of Münster in Ger- they send out signals for blood-vessel growth. 142 Humans can’t usually fight that signal — it to remain in magma rather than become incor- many. It revealed a deficit in Nd in four out overrides the normal complement of DSCR1 porated into crystallizing minerals. of seven rock samples. He and his coauthors that most of us have. But people with Down’s During the course of this work, the geologi- concluded that the rocks were derived from a syndrome have three copies of the gene, and cal field was stirred up by the discovery of rocks source formed during Hadean time — Earth’s we think that contributes to an ability to resist in southwest Greenland that provided evidence earliest geological aeon — and that some such the tumour’s signal. that a terrestrial magma ocean had crystallized Hadean reservoirs may be preserved in the to produce Earth’s crust and mantle within mantle beneath cratons (see page 1118). Were you surprised by your findings? 400 million years of the Solar System’s forma- Now Upadhyay is back in India as a faculty Yes. When you do studies of cells in culture, tion. Isotopic analysis of the Greenland rocks member. He is working to set up his own lab, you might express a gene 10,000-fold more had revealed an excess of neodymium-142 which will be the first in the country able to do than in its natural state to determine its compared with terrestial standards, which the kind of isotopic analysis required to track function. But the mice we used had just one indicated a separation of elements during that elements — and so Earth’s history. ■ extra copy of the DSCR1 gene and had more than 50% more DSCR1 protein than did the non-Down’s-syndrome models. The question was whether that extra amount would be FROM THE BLOGOSPHERE enough to shut down angiogenesis. It was. Academic reports may New York and the aid agency population lacks piped water, sound alarm bells, but do not CARE International predicts sewers, drains, health care or What does this mean for human cancers? necessarily spur governments large-scale migrations, and emergency services,” writes We’ve learned from earlier clinical trials into action. In a post on disruption to farming and water Pryadarshini. of anti-angiogenic agents that stopping Indigenus, Nature India editor supplies, as the Himalayan She notes that past academic the formation of new blood vessels once a cancer has taken root may come too late Subhra Priyadarshini highlights alpine glaciers melt. Meanwhile, reports and press coverage to arrest tumour development. We think two recent publications on the the London-based International of some of the world’s first that there is potential to develop an anti- effects of climate change on Institute of Environment and climate-change refugees have angiogenic pill that could be taken every day vulnerable human populations Development, has published a done little to change their — long before any cancer cells might begin (http://tinyurl.com/nqvq3t). book saying that a top priority, plight: “The migrants from to form — to stop tumours from growing in A report produced by the and no small task, is to “remedy these sinking islands [in the Bay the first place. If we can show that DSCR1 United Nations in collaboration deficits in infrastructure” in of Bengal] have not yet been blocks angiogenesis in the long term and has with Columbia University in cities where “at least half of the recognised as vulnerable.” ■ no side effects in mice, we will pass it on to Visit Nautilus for regular news relevant to Nature authors ➧ http://blogs.nature.com/nautilus and see industry. We’re pursuing this now. ■ Peer-to-Peer for news for peer reviewers and about peer review ➧ http://blogs.nature.com/peer-to-peer. 1032 © 2009 Macmillan Publishers Limited. All rights reserved 11032032 AuthorAuthor PPageage MMHH SASA NNEW.inddEW.indd 11032032 222/6/092/6/09 114:56:174:56:17 www.nature.com/nature Vol 459 | Issue no. 7250 | 25 June 2009 Cheerleader or watchdog? Science journalism is under threat. What can scientists do to help? hat should any researcher expect from a journalist beyond know which experts can provide context, and where appropriate criti- the keen intelligence needed to see the newsworthiness cism, of new results. But publishers tend to see that kind of expertise Wof the researcher’s work, and the ability to spell his or her as a luxury when money is tight, especially when the same space can name correctly? be easily filled with material from press releases and wire services. For some scientists, the answer is probably ‘Not much’. Many tend Scientists can do little to stem this bloodletting. But whatever they to think of science journalism as a kind of public-relations service, can do to engage with those caught up in it, and ensure that question- existing purely to explain new scientific findings to the masses. They ing and informed science journalism persists, will be worthwhile. If may well enjoy reading the results, and give points for a writer’s ability there is to be a transition to new — perhaps philanthropic — business to convey the excitement of a discovery, but they will mainly judge an models for in-depth reporting or new types of analytical media, sci- article on its scientific accuracy. ence journalism will integrate into them all the better if scientists are On top of this, some will see science journalism as an ally, useful for taking an active interest in its health. And if the future of the media shaping the public’s understanding of science-related issues such as truly is a dire landscape of top-100 lists, shouting heads and minimal nuclear proliferation, stem cells or genetically modified crops — and, attention span, then such efforts might at least defer the grim end. not incidentally, for making the case for a thriving research enterprise Even amid the turmoil, however, scientists can help ensure that to public and politicians alike.

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