http://www.xconomy.com/national/2010/11/17/roche-dumps-rnai-sends-shock-waves-through-alnylam-tekmira/ Roche said today it is terminating its efforts to discover and develop drugs through RNA interference, the hot gene-silencing technology that is supposed to be able to halt disease processes that are untouchable by existing biotech drugs or conventional small molecule pills. This means it’ s the end for RNAi research at Roche facilities in Kulmbach, Germany, Nutley , NJ, and Madison, WI. The company is cutting more than 4,000 jobs as part of its global restructuring, of which the RNAi move is just one part.
【在 s*r 的大作中提到】 : http://www.xconomy.com/national/2010/11/17/roche-dumps-rnai-sends-shock-waves-through-alnylam-tekmira/ : Roche said today it is terminating its efforts to discover and develop drugs : through RNA interference, the hot gene-silencing technology that is : supposed to be able to halt disease processes that are untouchable by : existing biotech drugs or conventional small molecule pills. This means it’ : s the end for RNAi research at Roche facilities in Kulmbach, Germany, Nutley : , NJ, and Madison, WI. The company is cutting more than 4,000 jobs as part : of its global restructuring, of which the RNAi move is just one part.
【在 s*r 的大作中提到】 : http://www.xconomy.com/national/2010/11/17/roche-dumps-rnai-sends-shock-waves-through-alnylam-tekmira/ : Roche said today it is terminating its efforts to discover and develop drugs : through RNA interference, the hot gene-silencing technology that is : supposed to be able to halt disease processes that are untouchable by : existing biotech drugs or conventional small molecule pills. This means it’ : s the end for RNAi research at Roche facilities in Kulmbach, Germany, Nutley : , NJ, and Madison, WI. The company is cutting more than 4,000 jobs as part : of its global restructuring, of which the RNAi move is just one part.
O*e
29 楼
我是一直不太明白为什么要去用RNAi治病,一是它特异性太差--副作用太大;二是 knock down某个或某些基因能治病的理念早已过时;三是knock-down efficiency很难 持久;四是RNAi delivery是个大难题。 RNAi就是一研究工具,跟knock-out or transgene一样。拿去治病不是开玩笑么。
1. why do you think it lacks specificity? just curious 2. a LOT of therapies are based on manipulation of one gene/one protein bah. .. 3 & 4 are true. However, there are multiple administration routes and multiple target organs which lead to different area under curve
RNAi is appealing due to theoretically easiness to design specific drugs. However, it is not very often a certain disease is simply caused by overproduction of some proteins.
bah.
【在 w******e 的大作中提到】 : 1. why do you think it lacks specificity? just curious : 2. a LOT of therapies are based on manipulation of one gene/one protein bah. : .. : 3 & 4 are true. However, there are multiple administration routes and : multiple : target organs which lead to different area under curve
w*e
33 楼
the same problem applies to other regimens too bah. what if you don't know which kinase/receptor to inhibit? BTW, I don't know other ways that may specifically increase the expression of certain gene variant like RNAa or ASO (except gene therapy, which is probably more notorious I guess hehe) btw, I'm not even in the RNAi field myself. just an intrigued bystander:)
【在 l*********s 的大作中提到】 : RNAi is appealing due to theoretically easiness to design specific drugs. : However, it is not very often a certain disease is simply caused by : overproduction of some proteins. : : bah.
l*s
34 楼
The effect of small molecules are localized to motif/domain of proteins, while RNAi targets the whole protein. I think the first approach will be less toxic in general as proteins are usually multi-functional.
【在 w******e 的大作中提到】 : the same problem applies to other regimens too bah. what if you don't know : which kinase/receptor to inhibit? : BTW, I don't know other ways that may specifically increase the expression : of certain gene variant like RNAa or ASO (except gene therapy, which is : probably more notorious I guess hehe) : btw, I'm not even in the RNAi field myself. just an intrigued bystander:)
w*e
35 楼
the whole point of say having a kinase is probably the kinase motif, isn't it? multi-functional proteins are mostly undruggable bah
【在 l*********s 的大作中提到】 : The effect of small molecules are localized to motif/domain of proteins, : while RNAi targets the whole protein. I think the first approach will be : less toxic in general as proteins are usually multi-functional.
s*r
36 楼
对呀 对呀,很多小分子要都是针对某个pathway来的, oncogene请展开说说你的2
bah.
【在 w******e 的大作中提到】 : 1. why do you think it lacks specificity? just curious : 2. a LOT of therapies are based on manipulation of one gene/one protein bah. : .. : 3 & 4 are true. However, there are multiple administration routes and : multiple : target organs which lead to different area under curve
It is true, but not the whole story: within in same motif family the affinity to targets vary broadly due to size and shapes. Optimization the specificity is what synthetic chemistry is about.
Sure it would nice to work on simple disease, but the questions is you don't have much freedom of choice: Easy targets are gone/picked first. You have to deal with the complexity of biological networks.
【在 w******e 的大作中提到】 : the whole point of say having a kinase is probably the kinase motif, : isn't it? multi-functional proteins are mostly undruggable bah
O*e
40 楼
真正的单基因疾病很少很少,我们做了这么多年的应该清楚,很多文章宣称的哪个基因 突变 导致哪个疾病,其实证据非常不足。 再往大了说,很多疾病不是简单的“基因"或“遗传”问题,牵扯到太多的因素。而 RNAi is designed to target only one or a few genes. 这个跟kinase inhibitor drugs区别还是很大,因为好的inhibitor只是抑制部分功能 ;而 knock-down是把整体的蛋白水平降低,这个的影响会非常广泛和难以控制。
Exactly. In terms of graph theory, the biological system is such a highly dense network that removing nodes have a much more profound impact than removing edges(interactions)
【在 O******e 的大作中提到】 : 真正的单基因疾病很少很少,我们做了这么多年的应该清楚,很多文章宣称的哪个基因 : 突变 : 导致哪个疾病,其实证据非常不足。 : 再往大了说,很多疾病不是简单的“基因"或“遗传”问题,牵扯到太多的因素。而 : RNAi : is designed to target only one or a few genes. : 这个跟kinase inhibitor drugs区别还是很大,因为好的inhibitor只是抑制部分功能 : ;而 : knock-down是把整体的蛋白水平降低,这个的影响会非常广泛和难以控制。
d*r
42 楼
but there's no big progress on the systems bio either. maybe the math is not enough. then we are totally screwed.
the don't have to deal with the complexity of biological networks.
【在 l*********s 的大作中提到】 : It is true, but not the whole story: within in same motif family the : affinity to targets vary broadly due to size and shapes. Optimization the : specificity is what synthetic chemistry is about. : : Sure it would nice to work on simple disease, but the questions is you don't : have much freedom of choice: Easy targets are gone/picked first. You have to deal with the complexity of biological networks.
t*o
43 楼
是不是有笔误啊,第一个edges是不是应该是nodes...
dense network that removing edges have a much more profound impact than removing edges(interactions)
【在 l*********s 的大作中提到】 : Exactly. In terms of graph theory, the biological system is such a highly dense network that removing nodes have a much more profound impact than removing edges(interactions)
l*s
44 楼
Maybe. But making no progress for a while is just natural. Nothing can grow exponentially to infinity.
【在 d*****r 的大作中提到】 : but there's no big progress on the systems bio either. : maybe the math is not enough. : then we are totally screwed. : : the : don't : have to deal with the complexity of biological networks.
l*s
45 楼
Yeah, it is a typo, thanks for pointing out
【在 t*******o 的大作中提到】 : 是不是有笔误啊,第一个edges是不是应该是nodes... : : dense network that removing edges have a much more profound impact than : removing edges(interactions)
d*r
46 楼
so the conclusion is, it will suck for a long time, before any major progress on the complexity network is made.
grow
【在 l*********s 的大作中提到】 : Maybe. But making no progress for a while is just natural. Nothing can grow : exponentially to infinity.
【在 O******e 的大作中提到】 : 真正的单基因疾病很少很少,我们做了这么多年的应该清楚,很多文章宣称的哪个基因 : 突变 : 导致哪个疾病,其实证据非常不足。 : 再往大了说,很多疾病不是简单的“基因"或“遗传”问题,牵扯到太多的因素。而 : RNAi : is designed to target only one or a few genes. : 这个跟kinase inhibitor drugs区别还是很大,因为好的inhibitor只是抑制部分功能 : ;而 : knock-down是把整体的蛋白水平降低,这个的影响会非常广泛和难以控制。
s*r
48 楼
治疗的话从来没有说要完全治好 对于多基因疾病,从单个基因逐个入手,一个一个改善,不也可以吗
【在 O******e 的大作中提到】 : 真正的单基因疾病很少很少,我们做了这么多年的应该清楚,很多文章宣称的哪个基因 : 突变 : 导致哪个疾病,其实证据非常不足。 : 再往大了说,很多疾病不是简单的“基因"或“遗传”问题,牵扯到太多的因素。而 : RNAi : is designed to target only one or a few genes. : 这个跟kinase inhibitor drugs区别还是很大,因为好的inhibitor只是抑制部分功能 : ;而 : knock-down是把整体的蛋白水平降低,这个的影响会非常广泛和难以控制。
d*r
49 楼
no. the key concept of network complexity is: linearly adding up single element is never going to be equivalent to, and not even remotely close to, the network as a whole.
做systems biology的就彻底不承认还原论了? 照你这么说,所有的linear models on observational studies都是无用 在一个广泛联系的系统里面,所有的main effect都没有意义?
【在 d*****r 的大作中提到】 : no. the key concept of network complexity is: : linearly adding up single element is never going to be equivalent to, and : not even remotely close to, the network as a whole.
l*s
52 楼
For small molecule, side effects are controllable though you cannot predict with great certainty what kind of modifications will work. But for RNAi, it is theoretically not controllable at all. Actually, the side effects of RNAi is testable with conditional knock out mice. I think this should definitely be the first step.
If the model does not correctly account for interactions when they are significant presence, conclusions from statistical inferences are misleading at best.
the reason linear models are still useful is: 1. some system were built at the beginning to be linear system, there're a lot of examples in engineering systems, like simple electronic circuits, or mechanical systems, etc. So of course you use linear system to study it. 2. some systems are too complicated and nonlinear, we don't have a good math to study these systems, so we use linear systems to approximate it. Unfortunately, most of this approximation is purely academic; the predictions are totally unacceptable for any industrial application. so, for the complex system like biological system, there's no real significance, meaning even you know exactly what each of the 1000 genes do, you are still far from understanding the whole network behavior, as far as if you didn't know any of the single genes.
【在 O******e 的大作中提到】 : 真正的单基因疾病很少很少,我们做了这么多年的应该清楚,很多文章宣称的哪个基因 : 突变 : 导致哪个疾病,其实证据非常不足。 : 再往大了说,很多疾病不是简单的“基因"或“遗传”问题,牵扯到太多的因素。而 : RNAi : is designed to target only one or a few genes. : 这个跟kinase inhibitor drugs区别还是很大,因为好的inhibitor只是抑制部分功能 : ;而 : knock-down是把整体的蛋白水平降低,这个的影响会非常广泛和难以控制。
the main issue w/ gene therapy is messing up the cell genome and lead to cancerous mutation bah? also, how else can you deal w/ undruggable targets or to compensate for mutated proteins?
简单的说,一个是增加某基因的表达,一个是减少某基因的表达,但达到这两个目的的 方式--delivery--几乎是一样的。你如果只是简单地送几个siRNA oligos过去, 效果很快就没有了;可你如果想用其它方式比如病毒载体,那一样是leading to cancers了。
【在 w******e 的大作中提到】 : the main issue w/ gene therapy is messing up the cell genome and lead : to cancerous mutation bah? : also, how else can you deal w/ undruggable targets or to compensate for : mutated proteins?
the current regimen of RNAi can at least last for a week, at least that's what ppl claimed. that seems to be a reasonable price to pay for something w/ NO alternative treatment bah(again, how else do we increase sth?)
【在 d*****r 的大作中提到】 : the reason linear models are still useful is: : 1. some system were built at the beginning to be linear system, there're : a lot of examples in engineering systems, like simple electronic : circuits, or mechanical systems, etc. So of course you use linear : system to study it. : 2. some systems are too complicated and nonlinear, we don't have a good : math to study these systems, so we use linear systems to approximate it. : Unfortunately, most of this approximation is purely academic; the : predictions are totally unacceptable for any industrial application. : so, for the complex system like biological system, there's no real
http://pipeline.corante.com/archives/2010/11/17/roche_has_problems_but_ rna_interference_has_more.php http://pipeline.corante.com/archives/2008/08/21/rnai_bubble_or_not.php I found this: 8. non-pharma chemist on November 17, 2010 5:10 PM writes... I'm not in pharma so I haven't been keeping myself abreast of developments in this that or the other nucleic acids. However, one friend of mine formerly worked at one of the companies with the siRNA technology. Another friend formerly worked at the company that bought that same technology. What did I hear from the purchasing company friend? "It doesn't work". Well, that's how it goes with the billions of $$ spent to "insource" drug candidates.
I think this is something about the current investment environment. Five years back, Alnylam could get millions from Novartis just for some early stage staff. Three years back, Merck would offer 1.1 billion for Sirna. Now it is totally different. Big pharma will not easily open their pocket unless they see pormising clinical programs. I think this a NO vote from Roche on RNAi drug discovery in near future. But when there is promise, they will surely come back.