美国科学家日前发现,癌细胞能够迅速增殖是因为它们唤醒了一种叫做“PKM2”的丙酮酸盐激酶。
据3月15日出版的《新科学家》杂志报道,健康细胞的大部分葡萄糖作为“燃料”被用来产生能量,但美国哈佛医学院的科学家却发现,在癌细胞中,葡萄糖主要用来产生脂肪和脱氧核糖核酸等新的细胞成分,从而造成细胞恶性增殖。
这一发现除了能解释癌细胞如何快速生长和复制外,还能解释为什么几乎所有类型的癌细胞都比健康细胞吸收更多的葡萄糖、并且燃烧葡萄糖产生能量的效率明显降低。这种变化使得癌细胞将更多葡萄糖用于细胞增殖。
此外,实验室研究和动物试验结果显示,一旦研究人员使用某种分子阻滞剂来抑制这种变化,癌细胞就会停止生长。
生物谷推荐原文阅读:
New Scientist
Hijacked fetal enzyme helps cancers grow
14 March 2008 Andy Coghlan Magazine issue 2647
NO WONDER tumour cells can grow and multiply so rapidly. It turns out that they reawaken an enzyme responsible for driving the explosive growth of fetuses.
Healthy cells use most of their glucose "fuel" to produce energy, rather than for building components of new cells, such as fats and DNA. But in cancer cells, the opposite happens. Now, Lewis Cantley of Harvard Medical School in Boston and his colleagues have identified the enzyme responsible for triggering this switch - a fetal form of pyruvate kinase, called PKM2.
"It's a bit like building materials being brought to a house," says Cantley. "Usually, cells burn all the material to make energy, but if you burn it all you can't use it to make a new house." In cancer cells, PKM2 blocks the burning of the building materials so that new tumour cells can be made instead.
As well as explaining how cancer ...