科学家驯服病毒攻击癌细胞

brucexm

Virus Tamed To Destroy Cancer Cells But Leave Healthy Cells Unharmed
牛津大学的科学家“驯服”了一种病毒，去除了它的关键毒性，使其能攻击和破坏癌细胞，但不损害健康细胞。他们的方法提供了一种新的平台，帮助改进癌症治疗和发展出针对众多病毒性疾病的新疫苗。 科学家发现，Cellular microRNA分子能控制不同细胞类型中mRNA的稳定性，这种机制提供基因改造病毒的可能性。研究人员成功的利用这种方法控制了腺病毒的增殖。腺病毒是一种广泛用于癌症治疗的DNA病毒，但也被发现能使老鼠的肝脏出现问题。研究人员筛选出导致肝病毒性退化的基因，减少了病毒产生的负效应，同时保持复制和杀死癌细胞的能力。具有复制能力的肿瘤杀手病毒是目前就基因治疗领域的热门主题，世界各地有许多临床试验正在进行之中。牛津大学的研究人员表示还需要至少两年时间才能进行临床测试。

ScienceDaily (May 25, 2009) — Scientists at Oxford University have tamed a virus so that it attacks and destroys cancer cells but does not harm healthy cells.  They determined how to produce replication-competent viruses with key toxicities removed, providing a new platform for development of improved cancer treatments and better vaccines for a broad range of viral diseases.


A common type of virus has been modified to attack cancer cells without harming healthy cells. (Credit: Copyright Oxford University)


Cellular microRNA molecules regulate the stability of mRNA in different cell types, and this newly-understood mechanism provides the possibility to engineer viruses for cell-specific inactivation. Cancer Research UK scientists at the University of Oxford, United Kingdom, with support from colleagues at Vrije Universiteit, Amsterdam, report that this approach can be used to regulate proliferation of adenovirus.
Adenovirus is a DNA virus widely used in cancer therapy but which causes hepatic disease in mice. Professor Len Seymour and colleagues found that introducing sites into the virus genome that are recognized by microRNA 122 leads to hepatic degradation of important viral mRNA, thereby diminishing the virus' ability to adversely affect the liver, while maintaining its ability to replicate in and kill tumor cells.
Tumor-killing replicating viruses are a hot topic in the biotherapeutics arena, with many clinical trials ongoing worldwide. That Professor Seymour's group set out to and has now defined a mechanism whereby wild type virus potency could be maintained in tumor cells but the virus could be 'turned off' in tissues vulnerable to pathology adds important information to the current base of knowledge.
"This approach is surprisingly effective and quite versatile. It could find a range of applications in controlling the activity of therapeutic viruses, both for cancer research and also to engineer a new generation of conditionally-replicating vaccines, where the vaccine pathogen is disabled in its primary sites of toxicity," Professor Seymour says.
The present study was intended mainly to explore and demonstrate the potential of this new mechanism to regulate virus activity. Although the current tumor-killing virus is useful in mice, transfer of the technology into the clinical setting will require re-engineering of the virus to overcome virus pathologies seen in humans, and it will be at least two years before this can be tested in the clinics.
Modified naturally-occurring viruses have already had important uses in medicine including their use as vaccines, notably for measles, mumps, polio, influenza, and chicken pox. They have already been developed as potential cancer-killing therapies, in an approach called virotherapy.
RC and FC are supported by Cancer Research UK; HC by a research studentship from the New Zealand Government, and MB by a Bellhouse Foundation Fellowship (Magdalen College, Oxford). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The authors have declared that no competing interests exist.



Journal reference:

• Cawood R, Chen HH, Carroll F, Bazan-Peregrino M, van Rooijen N, et al. Use of Tissue-Specific MicroRNA to Control Pathology of Wild-Type Adenovirus without Attenuation of Its Ability to Kill Cancer Cells. PLoS Pathog, 5(5): e1000440 DOI: 10.1371/journal.ppat.1000440

Adapted from materials provided by Public Library of Science, via EurekAlert!, a service of AAAS.



http://www.sciencedaily.com/releases/2009/05/090522081217.htm

yufeihuai

特深沉

感觉不靠谱，引狼入室，将来也无法确认其安全性。估计没人敢批准进行临床试验

特深沉

任何病毒，如果在人体内复制，都要干扰人体细胞自身的复制过程，都会诱导癌症。
将来这种病毒在人体内复制，变异了怎么办

走遍四方

认识是会改变的。。。

deng245

不断探索，不断失望。

nanhaiyangguang

FAWFDASFDSAFDAS

jangle

医学科学在不断进步，失败是成功之母。