Newly Discovered Biomarker Predicts Cancer Growth

    One of the most common questions cancer patients ask their doctors is: has the disease been contained or will it spread.  A recent study by U.S. and Chinese researchers may help provide clues.  The scientists examined genetic（遗传的,基因的） material from certain cancerous tumors and found that when high levels of a particular protein were present, there was a strong likelihood² that these cancers would spread within two years.
    The source of this discovery was among populations in Asia, where Hepatitis B and liver cancer are prevalent³.
    The World Health Organization estimates(估计、估算) in Asia, liver cancer caused by Hepatitis B is one of three major causes of death in men and a major cause in women.
    One fourth of the two billion people worldwide infected with the Hepatitis B virus eventually develop liver cancer and die.
    Scientists in Hong Kong had been studying samples of liver tumor¹ cells and found that some of the cells contained high levels of a variant⁴ of the protein Carboxypeptidase E or CPE.
    At the same time, scientists at the National Institute of Child Health and Human Development just outside Washington, D.C. were also studying CPE and also identified the same variant, now called CPE-Delta N.
    "We found that what's in cancer cells is in fact this variant form and so there we got together and [began] exploring this protein as this cancer protein," said Dr. Peng Loh, a neuro-endocrinologist at the National Institute.
    The scientists in Washington injected tissue from the Hong Kong liver samples into mice and confirmed that when CPE-Delta N was present, there was a strong likelihood the cancer would metastacize, or spread, within two years.
    CPE-Delta N has also been identified（被识别的） in cancers of the head and neck, colon,  and breast. Preliminary tests indicate it may also be present in thyroid cancer.
    In all, Dr. Loh says there could be as many as 14 types of cancer where CPE-Delta N is found.
    "So we're very careful to say that each one has to be tested in its own right, but I think that it looks like it might cover quite a few," he said.
    The researchers say the discovery could change treatment options for patients, especially those identified as having Stage I or II cancer and who carry CPE-Delta N.
    "We feel that those are the ones that we can help the most, because they were the ones who were told most likely you won't get recurrence⁵, so let's not treat," Dr. Loh said.  "If we catch those, we have saved some people's lives."The study was published in the Journal of Clinical Investigation⁶.(本文由在线英语听力室整理编辑)

1 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。

2 likelihood   

n.可能，可能性

参考例句：

• We must try our best to reduce the likelihood of war.我们必须尽最大努力减少战争的可能性。
• I don't think there is any likelihood of his agreeing to it.我认为不会有他同意那件事情的可能。

3 prevalent   

adj.流行的，普遍的

参考例句：

• The habit of travelling by aeroplane is becoming more prevalent.乘飞机旅行的习惯变得越来越盛行了。
• Colds are prevalent in the winter.伤风在冬季很普遍。

4 variant   

adj.不同的，变异的；n.变体，异体

参考例句：

• We give professional suggestions according to variant tanning stages for each customer.我们针对每位顾客不同的日晒阶段，提供强度适合的晒黑建议。
• In a variant of this approach,the tests are data- driven.这个方法的一个变种，是数据驱动的测试。

5 recurrence   

n.复发，反复，重现

参考例句：

• More care in the future will prevent recurrence of the mistake.将来的小心可防止错误的重现。
• He was aware of the possibility of a recurrence of his illness.他知道他的病有可能复发。

6 investigation   

n.调查，调查研究

参考例句：

• In an investigation,a new fact became known, which told against him.在调查中新发现了一件对他不利的事实。
• He drew the conclusion by building on his own investigation.他根据自己的调查研究作出结论。