《中英文對照讀新聞》Elephants’ low cancer rates explained 大象的低癌症率獲得解釋
Elephants have enhanced defences against cancer that can prevent tumours forming, say scientists.
There is a train of thought that says every cell can become cancerous so the more of them you have, the more likely you are to get cancer. So if an elephant has 100 times as many cells as a person then the trunk-swinging mammals should be 100 times more likely to have the disease.
And yet the analysis, published in the Journal of the American Medical Association, showed only 5% of elephants die from cancer compared to up to 25% of people. The scientists turned to the elephant’s DNA - the blueprint of life - to find an explanation.
Cancer is caused by mutations in a cell’s DNA that produce faulty instructions leading to rampant growth as the cell spirals out of control.
But animals also have "smoke alarms" that detect the damage and either lead to the cell being repaired or killed. One of these alarms is called TP53, and while humans have one TP53 gene, elephants have 20. As a result, elephants seem far more keen to kill off cells on the cusp of going rogue.
rain of thought︰片語，思路。例句：What amazing train of thought led you from Napoleon to global warming?
turn to︰片語，（尤指因不開心）開始使用（不好的東西），開始做（不當之事）。例句：She turned to drugs after the break-up of her marriage.（婚姻破裂後她開始吸毒。）
on the cusp of︰片語，處於……的開端。例句：We are on the cusp of a new age marked by gender equality .（ 我們正處於一個性別平等時代的開端。）