ScienceNow: Hunting Down Cancer

癌症研究人员长期寻求一种能够摧毁肿瘤而不损害身体其他部位的化疗替代疗法。最近的一项研究可能为这一目标带来了希望。研究团队设计了一种能特异性结合肿瘤细胞表面GRP78蛋白的氨基酸短链,并将其与一种触发细胞凋亡的小型蛋白质融合,形成一种“智能炸弹”。在小鼠实验中,这种分子准确地定位并摧毁了移植的人类前列腺肿瘤,而未对其他组织造成伤害。
Cancer researchers have long sought an alternative treatment to chemotherapy that can destroy tumors without damaging the rest of the body. A new study with mouse and human tumors may put such a treatment within reach.

Designing drugs to target cancer is a challenge because cancerous cells are well camouflaged within otherwise healthy tissues. But researchers have begun to find molecular tags unique to cancer cells. Last year, Wadih Arap and Renata Pasqualini, a husband-and-wife team of cancer biologists at the M. D. Anderson Cancer Center at the University of Texas, Houston, identified a protein called GRP78 expressed by prostate cancer cells and not by healthy tissues. They knew they'd found a promising drug target because GRP78 is expressed on the cell surface, where it's easily accessible to drugs. Additionally, a drug targeted to GRP78 should be unlikely to attack healthy cells because GRP78 is a so-called stress response protein which is only expressed on the surface of cells under stressful conditions such as those that occur within the oxygen-poor lump of a tumor.

To test GRP78 as a target, a team led by Arap and Pasqualini designed a short string of amino acids that binds specifically to the surface of the GRP78 protein. They then fused this string to a small corkscrew-shaped protein that, when internalized, triggers the cell to commit suicide. The team hoped that the hybrid molecule would act as a tumor-seeking missile when injected into the bloodstream.

The missile appears to be deadly accurate. Reporting in the September issue of Cancer Cell, the team shows that its hybrid molecule located and destroyed human prostate tumors transplanted into mice, without harming any other kind of tissue. It did the same for breast tumors. The next step, say Arap and Pasqualini, is a series of preclinical studies to determine its safety for clinical trials in humans.

Over the past decade, Arap and Pasqualini have pioneered the "smart bomb" approach to cancer therapy, says Bruce Zetter, a cancer researcher at Harvard Medical School in Boston. This study "shows how close we are getting" to putting the strategy into action.

--JOHN BOHANNON

 
评论
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值