Diabetes drug shows promise in reducing risk of cancer

 　　WASHINGTON, Nov. 24 (Xinhua) -- An inexpensive drug that treats Type 2 diabetes¹ has been shown to prevent a number of natural and man-made chemicals from stimulating² the growth of breast cancer cells, according to a newly published study by a Michigan State University researcher.

　　The research, led by pediatrics professor James Trosko and colleagues from South Korea's Seoul National University, provides biological evidence for previously³ reported epidemiological surveys that long-term use of the drug metformin for Type 2 diabetes reduces the risk of diabetes-associated cancers, such as breast cancers.

　　The research appeared online this week in PLoS One.

　　For the study, Trosko and colleagues focused on the concept that cancers originate from adult human stem cells and that there are many natural and man-made chemicals that enhance the growth of breast cancer cells. Using culture dishes, they grew miniature human breast tumors, or mammospheres, that activated⁵ a certain stem cell gene⁶.

　　Then the mammospheres were exposed to natural estrogen -- a known growth factor and potential breast tumor⁴ promoter -- and man-made chemicals that are known to promote tumors or disrupt the endocrine system.

　　The team found that estrogen and the chemicals caused the mammospheres to increase in numbers and size. However, with metformin added, the numbers and size of the mammospheres were dramatically reduced. While each of the chemicals enhanced growth by different means, metformin seemed to be able to inhibit⁷ their stimulated⁸ growth in all cases.

　　"While future studies are needed to understand the exact mechanism⁹ by which metformin works to reduce the growth of breast cancers, this study reveals the need to determine if the drug might be used as a preventive drug and for individuals who have no indication of any existing cancers," Trosko said.

1 diabetes   

n.糖尿病

参考例句：

• In case of diabetes, physicians advise against the use of sugar.对于糖尿病患者，医生告诫他们不要吃糖。
• Diabetes is caused by a fault in the insulin production of the body.糖尿病是由体內胰岛素分泌失调引起的。

2 stimulating   

adj.有启发性的，能激发人思考的

参考例句：

• shower gel containing plant extracts that have a stimulating effect on the skin 含有对皮肤有益的植物精华的沐浴凝胶
• This is a drug for stimulating nerves. 这是一种兴奋剂。

3 previously   

adv.以前，先前（地）

参考例句：

• The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。
• Let me digress for a moment and explain what had happened previously.让我岔开一会儿，解释原先发生了什么。

4 tumor   

n.（肿）瘤，肿块(英)tumour

参考例句：

• He was died of a malignant tumor.他死于恶性肿瘤。
• The surgeons irradiated the tumor.外科医生用X射线照射那个肿瘤。

5 activated   

adj. 激活的 动词activate的过去式和过去分词

参考例句：

• The canister is filled with activated charcoal.蒸气回收罐中充满了活性炭。

6 gene   

n.遗传因子，基因

参考例句：

• A single gene may have many effects.单一基因可能具有很多种效应。
• The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。

7 inhibit   

vt.阻止，妨碍，抑制

参考例句：

• Don't let ego and greed inhibit clear thinking and hard work.不要让自我和贪婪妨碍清晰的思维和刻苦的工作。
• They passed a law to inhibit people from parking in the street.他们通过一项法令以阻止人们在街上停车。

8 stimulated   

a.刺激的

参考例句：

• The exhibition has stimulated interest in her work. 展览增进了人们对她作品的兴趣。
• The award has stimulated her into working still harder. 奖金促使她更加努力地工作。

9 mechanism   

n.机械装置；机构，结构

参考例句：

• The bones and muscles are parts of the mechanism of the body.骨骼和肌肉是人体的组成部件。
• The mechanism of the machine is very complicated.这台机器的结构是非常复杂的。