Cancer Stem Cells Capture Attention of Scientists

Cancer Stem Cells Capture Attention of Scientists
Evidence is seen for a possible cause of solid tumors, but many questions remain. Transcript of radio broadcast:
24 June 2008

This is the VOA Special English Health Report.

Some experts predict that doctors will someday use stem cells to treat many different diseases. Yet so far there has been less progress in stem cell therapies than many had hoped.

For years, scientists have studied stem-cell treatment of cancer. Doctors now use stem cells in therapies for several forms of the disease. But at the same time, researchers increasingly are examining a possible connection between stem cells and cancer.

A large number of researchers now point to stem cells as a possible cause of solid tumors. Studies have reported identifying cancer stem cells.

Stem cells can develop into any kind of cell, like skin, blood or brain cells. Embryos have more stem cells than adults. Embryonic stem cells can develop into all the many different tissues that form the body.

But there are stem cells that remain throughout a person's life to replace cells that become damaged. When a stem cell divides, one of the two cells remains a stem cell. The other becomes a specialized cell.

Many questions remain to be answered. But the general thinking seems to be that cancer stem cells represent a small population of the cells in a tumor. Some researchers think these cancer stem cells have the ability to divide and change into other types of cells. As a result, they think the stem cells help the cancer to metastasize, or spread to other organs.

The researchers also think cancer stem cells are able to repair and feed tumors so they continue to grow. They suspect that the cells are even able to repair damage from radiation treatment and form new tumors. This could explain why some cancers resist drug therapies.

Much of the research into cancer stem cells is being done in California and Canada. Last week, Canadian Health Minister Tony Clement and California Governor Arnold Schwarzenegger announced joint efforts. Their governments agreed to provide one hundred million dollars each over the next three years for research into cancer stem cells.

A California company says it is close to tests in humans of a drug that would directly target cancer stem cells. Two scientists who led the discovery of cancer stem cells in solid tumors, Michael Clarke and Max Wicha, started OncoMed Pharmaceuticals four years ago. OncoMed has signed an agreement with a major drug company, GlaxoSmithKline, to work on the experimental treatment.

And that's the VOA Special English Health Report, written by Caty Weaver. I'm Steve Ember.

----------------------------Google Translate

癌症干细胞是吸引注意力的科学家
证据被认为是一个可能的原因固体肿瘤，但许多问题仍然存在。全文电台广播：
2008年6月24日

这是美国之音特别英语卫生报告。

一些专家预测，医生会使用干细胞治疗许多不同的疾病。然而，直至目前为止，一直进展不大，在干细胞疗法比许多人所希望的。

多年来，科学家们研究干细胞治疗癌症。医生现在使用干细胞在治疗几种形式的疾病。但在同一时间内，研究人员越来越多正在研究一种可能之间的联系，干细胞和癌症。

大量的研究人员现在可以点干细胞作为一种可能的原因，实体肿瘤。研究报告确定癌症干细胞。

干细胞可以发展成为任何类型的细胞，如皮肤，血液或脑细胞。有更多的胚胎干细胞比成人。胚胎干细胞，可以发展成为所有的许多不同的组织形式的机构。

但也有干细胞仍然整个人的生命，以取代细胞，成为损坏。当干细胞分化，其中两个细胞仍然是一个干细胞。其他成为一个专门的细胞。

许多问题有待回答。但总的思想，似乎是癌症干细胞所代表的人口少的细胞在肿瘤。一些研究者认为，这些癌症干细胞有能力分化和转变成其他类型的细胞。因此，他们认为干细胞的帮助癌症转移，或蔓延到其他器官。

研究人员还认为，癌症干细胞能够修复和饲料肿瘤，使他们继续成长。他们怀疑该细胞，甚至能修复放射治疗和形成新的肿瘤。这可以解释为什么某些癌症的抵制药物疗法。

大部分的研究癌症干细胞正在做在加利福尼亚州和加拿大。上周，加拿大卫生部长托尼克莱门特和加州州长阿诺史瓦辛格宣布共同努力。他们的政府同意提供1.0亿美元，每个在未来三年内为研究癌症干细胞。

加州的公司说，这是接近测试，在人类的药物会直接针对癌症干细胞。两位科学家谁主导发现的癌症干细胞的实体肿瘤，迈克尔克拉克和最高维夏，开始oncomed药品四年前。 oncomed签署了一项协议，正与一家大型制药公司，葛兰素史克公司，工作，对实验性治疗。

这是该美国之音特别英语卫生报告，书面，由caty维夫。我史蒂夫ember