通过巨兽揭开癌症的神秘面纱【经济学人精讲】第321期
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本文选自《经济学人》2019年6月29日文章。癌症始于单细胞的突变，按照正常逻辑，拥有巨量细胞的鲸鱼、大象得癌症的几率更大，但实际的研究表明，地球上的庞然大物有着极低的癌症发病率。所以有研究者认为，一些生物的巨型身体和抗肿瘤能力是同步进化的，抑制癌症的秘密很可能隐藏在这些庞然大物的基因中。
由于篇幅较长，本文节选原文标题和全文重点段落进行精讲，
选文精讲
Oncology 肿瘤学
In fighting cancer, look to what other animals do
在对抗癌症方面，看看其他动物是怎么做的
Big species have fewer tumours than small ones
大的物种比小的物种肿瘤要少
Jun 29th 2019 | PHOENIX, ARIZONA
IN 1977 RICHARD PETO, an epidemiologist at Oxford University, observed a contradiction. Cancer begins as a mutation in a single cell. Organisms with more cells should therefore have a higher risk of developing it. Elephants, which have 100 times as many cells as human beings do, should swarm with malignancies. Whales, with ten times more again, should be barnacled with tumours. In fact, the planet’s behemoths are blessed with extremely low rates of cancer. Titanic bodies and tumour resistance have evolved in tandem. The secret of suppressing cancer may therefore be hidden in the genes of giants.
epidemiologist: 肿瘤学家
mutation: 突变
swarm with: 充满
malignancy: 恶性（肿瘤）
be barnacled with: 缠绕、布满
behemoth: 巨兽
in tandem: 紧接着、一前一后的
1977年，牛津大学流行病学家RICHARD PETO发现了一个矛盾。癌症开始于单个细胞的突变，因此，拥有越多细胞的生物体应该具有更高癌变的风险。大象的细胞数量是人类的100倍，它们应该全身遍布恶性肿瘤。鲸鱼的细胞又比大象多10倍，它们应该被肿瘤包围。事实上，地球上的庞然大物拥有极低的癌症发病率。巨大的身体和抗肿瘤能力是同步进化的。因此，抑制癌症的秘密可能隐藏在庞然大物的基因中。
Inspired by Peto’s paradox, as this contradiction has come to be known, researchers are exploring rates of cancer and resistance to cancer in thousands of animal species, with an emphasis on heavyweights. Their hope is to translate the animals’ cancer-fighting talents into treatments for people.
随着这种矛盾被越来越多的人知道，受Peto悖论的启发，研究人员对上万种动物进行研究，研究它们的癌症发病率和对癌症的抵抗力，重点是重量级动物。他们希望能通过这些动物的抗癌能力，找到治疗人类癌症的方法。
In one recent study, published in Molecular Biology and Evolution and entitled “Return to the sea, get huge, beat cancer”, Marc Tollis of Northern Arizona University and his colleagues sequenced the genome of the humpback whale and began trawling through it for tumour-suppressor genes. Previous research had revealed that, around 50m years ago, creatures which looked something like a cross between a rat and a wolf dog-paddled into the sea and eventually evolved into whales. These animals remained fairly small until about 3m years ago. Then they rapidly ballooned into whoppers the size of buses.
humpback whale: 座头鲸
trawle: 网罗、彻底搜查
whopper: 特别大的东西
在最近发表在《分子生物学与进化》杂志上的名为“回到海洋，找到巨兽，击败癌症”的一项研究中，北亚利桑那大学的马克·托利斯和他的同事们对座头鲸的基因组进行了测序，并开始在其中搜寻肿瘤抑制基因。此前的研究表明，大约5000万年前，一些看起来像老鼠和狼狗杂交的动物划入大海，最终进化成鲸鱼。直到大约300万年前，这些动物还相当小。然后他们迅速膨胀成巴士那么大的庞然大物。