A new superweapon in the fight against cancer | Paula Hammond

翻译人员: Hong Li 校对人员: Yinchun Rui

Cancer affects all of us --

癌症是我们每个人的大敌——

especially the ones that come back over and over again,

尤其是那些不断复发的，

the highly invasive and drug-resistant ones,

容易扩散的，具有抗药性的癌症，

the ones that defy medical treatment,

药物治疗对它们无效，

even when we throw our best drugs at them.

即使我们用最好的药也无济于事。

Engineering at the molecular level,

在分子级别进行（基因）工程改造，

working at the smallest of scales,

从最小结构层面着手，

can provide exciting new ways

（我们就）能找到意想不到的新办法

to fight the most aggressive forms of cancer.

同最致命的癌症进行斗争。

Cancer is a very clever disease.

癌症是一种很狡猾的疾病。

There are some forms of cancer,

幸运的是，对于一些癌症，

which, fortunately, we've learned how to address relatively well

我们可以通过一些 验证过的药物和手术

with known and established drugs and surgery.

进行治疗，可以 得到相对较好的结果。

But there are some forms of cancer

但有几种癌症

that don't respond to these approaches,

这些方法对它们都无效，

and the tumor survives or comes back,

即使在药物的猛烈攻击下，

even after an onslaught of drugs.

肿瘤依然能够存活，或者复发。

We can think of these very aggressive forms of cancer

我们可以将这几种致命的癌症

as kind of supervillains in a comic book.

想象成漫画书里面的大反派。

They're clever, they're adaptable,

他们狡猾，适应性强，

and they're very good at staying alive.

生存能力一流。

And, like most supervillains these days,

而且，跟现在（漫画书里） 大多数大反派一样，

their superpowers come from a genetic mutation.

他们的超能力来自基因突变。

The genes that are modified inside these tumor cells

这些肿瘤细胞的基因不断变化，

can enable and encode for new and unimagined modes of survival,

能找到新的、意想不到的生存方式，

allowing the cancer cell to live through

可以让癌细胞抵抗住

even our best chemotherapy treatments.

我们最强大的化学治疗。

One example is a trick in which a gene allows a cell,

有一个例子很神奇， 基因能让细胞

even as the drug approaches the cell,

在药物接近之前，

to push the drug out,

把药物推开，

before the drug can have any effect.

药物根本来不及起任何作用。

Imagine -- the cell effectively spits out the drug.

就好比细胞一口把药吐出去。

This is just one example of the many genetic tricks

而这仅仅是我们的大反派——癌症的

in the bag of our supervillain, cancer.

众多基因把戏之一。

All due to mutant genes.

这一切都跟突变基因有关。

So, we have a supervillain with incredible superpowers.

因此，我们要面对的是 拥有超强能力的大反派。

And we need a new and powerful mode of attack.

我们需要新的、 更强大的攻击方式。

Actually, we can turn off a gene.

实际上，我们可以关闭基因。

The key is a set of molecules known as siRNA.

开关是一系列叫siRNA的分子 （即小分子干扰核糖核酸）。

siRNA are short sequences of genetic code

它是一小段基因编码，

that guide a cell to block a certain gene.

可以让细胞阻止 某些特定基因（发挥作用）。

Each siRNA molecule can turn off a specific gene

每一个siRNA都能 关闭细胞内部

inside the cell.

某个特定的基因。

For many years since its discovery,

自siRNA被发现后，

scientists have been very excited

科学家们兴奋了好多年，

about how we can apply these gene blockers in medicine.

因为他们可以将这种 基因拦截者加入药物中。

But, there is a problem.

但是，有一个问题。

siRNA works well inside the cell.

siRNA在细胞内部 可以正常发挥作用。

But if it gets exposed to the enzymes

但如果它接触到

that reside in our bloodstream or our tissues,

位于我们血液或者组织中的酶的话，

it degrades within seconds.

几秒钟内就会被降解。

It has to be packaged, protected through its journey through the body

因此，它们必须被包裹及保护起来， 才能完成在人身体里的旅程，

on its way to the final target inside the cancer cell.

顺利抵达最终目标 ——癌细胞内部。

So, here's our strategy.

因此，我们的策略如下。

First, we'll dose the cancer cell with siRNA, the gene blocker,

首先，我们将siRNA—— 基因拦截者——用在癌细胞身上，

and silence those survival genes,

让（癌细胞的）生存基因失效，

and then we'll whop it with a chemo drug.

然后我们再用化学药品来对付癌细胞。

But how do we carry that out?

但如何实现呢？

Using molecular engineering,

答案是分子工程技术，

we can actually design a superweapon

我们可以设计一种超级武器，

that can travel through the bloodstream.

能在血液循环中存活下来。

It has to be tiny enough to get through the bloodstream,

它必须足够小，才可以进入血液循环，

it's got to be small enough to penetrate the tumor tissue,

穿过肿瘤组织，

and it's got to be tiny enough to be taken up inside the cancer cell.

进入癌细胞内部。

To do this job well,

要做到这一点，

it has to be about one one-hundredth the size of a human hair.

它的尺寸必须小到 头发的百分之一。

Let's take a closer look at how we can build this nanoparticle.

来仔细看一下我们是 如何制造这种纳米粒子的。

First, let's start with the nanoparticle core.

首先，我们要制造纳米核。

It's a tiny capsule that contains the chemotherapy drug.

那是一颗小胶囊， 内含化学药剂。

This is the poison that will actually end the tumor cell's life.

对肿瘤细胞而言是致命毒药。

Around this core, we'll wrap a very thin,

在内核周围，我们包上一层很厚的

nanometers-thin blanket of siRNA.

——当然也就几纳米厚——的siRNA。

This is our gene blocker.

这是我们的基因拦截者。

Because siRNA is strongly negatively charged,

因为siRNA带负电，

we can protect it

我们用一层

with a nice, protective layer of positively charged polymer.

坚固的，带正电的 聚合物来保护它。

The two oppositely charged molecules stick together

这两种带有不同电荷的分子

through charge attraction,

相互吸引，

and that provides us with a protective layer

形成一层保护膜

that prevents the siRNA from degrading in the bloodstream.

防止siRNA在血液中被降解。

We're almost done.

别着急，我快说完了。

(Laughter)

（笑声）

But there is one more big obstacle we have to think about.

但前方还有一个 大障碍需要跨越。

In fact, it may be the biggest obstacle of all.

而且，也许是最大的一个障碍。

How do we deploy this superweapon?

我们该如何部署这件超级武器？

I mean, every good weapon needs to be targeted,

每一件武器都要设定目标，

we have to target this superweapon to the supervillain cells

我们要将这件超级武器 瞄准潜伏在肿瘤内部的

that reside in the tumor.

超级大反派。

But our bodies have a natural immune-defense system:

但人体是有免疫系统的：

cells that reside in the bloodstream

血液里的各种细胞

and pick out things that don't belong,

能辨认出外来物体，

so that it can destroy or eliminate them.

然后杀死或清除它们。

And guess what? Our nanoparticle is considered a foreign object.

很显然，我们的纳米粒子 就是一种外来物体。

We have to sneak our nanoparticle past the tumor defense system.

我们要让它骗过肿瘤的防御系统。

We have to get it past this mechanism of getting rid of the foreign object

我们要伪装它， 帮它通过重重岗哨，

by disguising it.

进入敌营。

So we add one more negatively charged layer

于是我们再加上一层 带负电的保护膜

around this nanoparticle,

包住我们的纳米粒子，

which serves two purposes.

目的有两个。

First, this outer layer is one of the naturally charged,

第一，最外面这层保护膜 是存在于我们体内的

highly hydrated polysaccharides that resides in our body.

带电多糖水合物之一。

It creates a cloud of water molecules around the nanoparticle

它能在纳米粒子周围 形成许多水分子，

that gives us an invisibility cloaking effect.

就像给纳米粒子穿上了隐形披风。

This invisibility cloak allows the nanoparticle

这件披风能帮助纳米粒子

to travel through the bloodstream

在血液里自由行动，

long and far enough to reach the tumor,

畅通无阻，

without getting eliminated by the body.

直到抵达肿瘤细胞。

Second, this layer contains molecules

第二，这层保护膜含有一些分子，

which bind specifically to our tumor cell.

专门用来与肿瘤细胞结合。

Once bound, the cancer cell takes up the nanoparticle,

一旦结合，癌细胞 就会把纳米粒子吸收，

and now we have our nanoparticle inside the cancer cell

这样我们的纳米粒子最终就会进入癌细胞，

and ready to deploy.

准备发起进攻。

Alright! I feel the same way. Let's go!

是啊！我也觉得很兴奋。继续！

(Applause)

（掌声）

The siRNA is deployed first.

siRNA首先开始行动。

It acts for hours,

它需要几个小时，

giving enough time to silence and block those survival genes.

来让（癌细胞的）生存基因失效。

We have now disabled those genetic superpowers.

我们去除了（癌细胞的）基因超能力。

What remains is a cancer cell with no special defenses.

只剩下没有防御的癌细胞。

Then, the chemotherapy drug comes out of the core

之后化学药剂从内核中释放出来

and destroys the tumor cell cleanly and efficiently.

干净利落地杀死肿瘤细胞。

With sufficient gene blockers,

只要有足够多的基因拦截者，

we can address many different kinds of mutations,

我们就能对付各种变异（的癌细胞），

allowing the chance to sweep out tumors,

有机会消灭肿瘤，

without leaving behind any bad guys.

不留落网之鱼。

So, how does our strategy work?

那么，我们的方法到底有没有效呢？

We've tested these nanostructure particles in animals

我们进行了动物实验，

using a highly aggressive form of triple-negative breast cancer.

使用的是一种非常厉害的 癌症，三阴性乳腺癌。

This triple-negative breast cancer exhibits the gene

它的基因非常厉害，

that spits out cancer drug as soon as it is delivered.

能迅速将抗癌药排出。

Usually, doxorubicin -- let's call it "dox" -- is the cancer drug

通常，我们会使用阿霉素这种抗癌药，

that is the first line of treatment for breast cancer.

它是治疗乳腺癌的首选手段。

So, we first treated our animals with a dox core, dox only.

第一次，我们只用 阿霉素来对动物进行治疗。

The tumor slowed their rate of growth,

肿瘤的增长率有所减缓，

but they still grew rapidly,

但还是增长很快，

doubling in size over a period of two weeks.

两周之内就增长了一倍。

Then, we tried our combination superweapon.

接下来，我们的超级武器上场了。

A nanolayer particle with siRNA against the chemo pump,

外层是siRNA， 保护自身不被拦截，

plus, we have the dox in the core.

内核部分是阿霉素。

And look -- we found that not only did the tumors stop growing,

结果我们发现， 肿瘤不但没有增长，

they actually decreased in size

而且变小了，

and were eliminated in some cases.

在某些样本上甚至完全消失。

The tumors were actually regressing.

肿瘤被击退了。

(Applause)

（掌声）

What's great about this approach is that it can be personalized.

这种方法最大的好处就是可以定制。

We can add many different layers of siRNA

我们可以添加多重siRNA

to address different mutations and tumor defense mechanisms.

分别针对不同的变异和防御机制。

And we can put different drugs into the nanoparticle core.

我们还可以在内核中 放入不同种类的药物。

As doctors learn how to test patients

随着医生掌握测试方法，

and understand certain tumor genetic types,

弄清肿瘤的特定基因类型，

they can help us determine which patients can benefit from this strategy

就能帮我们确定 哪些病人能使用这种疗法，

and which gene blockers we can use.

应该选用哪种基因拦截者。

Ovarian cancer strikes a special chord with me.

我想特别说说卵巢癌。

It is a very aggressive cancer,

它是一种非常可怕的癌症，

in part because it's discovered at very late stages,

一部分原因是它只有 在晚期才能被发现，

when it's highly advanced

那时病情已经很严重

and there are a number of genetic mutations.

而且伴随很多基因突变。

After the first round of chemotherapy,

在首轮化疗结束之后，

this cancer comes back for 75 percent of patients.

有75%的患者会复发。

And it usually comes back in a drug-resistant form.

而且复发之后通常都有抗药性。

High-grade ovarian cancer

晚期卵巢癌

is one of the biggest supervillains out there.

是最大的超级反派之一。

And we're now directing our superweapon

它是我们的超级武器

toward its defeat.

下一个目标。

As a researcher,

作为一名研究者，

I usually don't get to work with patients.

我通常很少与病人接触。

But I recently met a mother

但最近我遇到了一位母亲

who is an ovarian cancer survivor, Mimi, and her daughter, Paige.

她叫咪咪，是一名卵巢癌幸存者， 她有个女儿叫佩吉。

I was deeply inspired by the optimism and strength

她们母女俩表现出来的乐观和坚强，

that both mother and daughter displayed

勇气和相互支持，

and by their story of courage and support.

深深地打动了我。

At this event, we spoke about the different technologies

我们聊到了用于治疗癌症的

directed at cancer.

科技手段。

And Mimi was in tears

咪咪听得流泪了，

as she explained how learning about these efforts

她说，了解到目前 取得的这些成就，

gives her hope for future generations,

让她看到了下一代人 （不受癌症折磨）的希望，

including her own daughter.

其中包括她的女儿。

This really touched me.

这让我很是感慨。

It's not just about building really elegant science.

（我们所做的）不仅仅是 建立一门优秀的科学。

It's about changing people's lives.

而是在改变人的命运。

It's about understanding the power of engineering

是要了解分子工程学

on the scale of molecules.

强大的力量。

I know that as students like Paige move forward in their careers,

我坚信，随着像佩吉这样的学生 沿着这条道路不断前进，

they'll open new possibilities

他们一定能打开一片新天地，

in addressing some of the big health problems in the world --

解决当今世界最大的健康问题，

including ovarian cancer, neurological disorders, infectious disease --

包括卵巢癌，神经系统疾病，传染病——

just as chemical engineering has found a way to open doors for me,

就如同化学基因改造已经 为我指明了一条道路，

and has provided a way of engineering

提供了一种基因改造的方法，

on the tiniest scale, that of molecules,

让我们可以从小小的分子入手，

to heal on the human scale.

解决人类健康这个大问题。

Thank you.

谢谢大家。

(Applause)

（掌声）