What the sugar coating on your cells is trying to tell you | Carolyn Bertozzi

翻译人员: chunhua zhang 校对人员: Chen Zou

This is a talk about sugar and cancer.

这是一个关于糖和癌症的演讲，

I became interested in sugar when I was in college.

我是在上大学的时候 开始对糖感兴趣的。

Not this kind of sugar.

我说的不是这种糖，

It was the sugar that our biology professors taught us about

我说的是生物学教授教我们的

in the context of the coating of your cells.

包裹在你细胞上的那种糖。

Maybe you didn't know that your cells are coated with sugar.

可能你不知道你的细胞 被糖蛋白包裹着。

And I didn't know that, either,

我之前也不知道，

until I took these courses in college,

直到上大学的时候上了这些课，

but back then --

但在当时——

and this was in, let's just call it the 1980s --

那是在，我们就说 1980年代吧——

people didn't know much about why our cells are coated with sugar.

人们对于为什么细胞被 糖蛋白包裹所知甚少。

And when I dug through my notes, what I noticed I had written down

当我翻遍笔记本时， 注意到我曾经写下

is that the sugar coating on our cells is like the sugar coating

我们细胞上的糖蛋白就像是

on a peanut M and M.

花生巧克力上的糖衣。

And people thought the sugar coating on our cells

而人们曾以为 我们细胞上的糖蛋白

was like a protective coating

就像是一个保护层，

that somehow made our cells stronger or tougher.

在某种程度上使细胞 更强大或者坚韧。

But we now know, many decades later,

但是几十年后的今天，我们知道

that it's much more complicated than that,

实际情况要复杂得多，

and that the sugars on our cells are actually very complex.

我们细胞上的糖蛋白 实际上非常复杂。

And if you could shrink yourself down to a little miniature airplane

如果你能将自己缩小 塞进一个微型飞机，

and fly right along the surface of your cells,

然后沿着你的细胞表层飞行

it might look something like this --

就可能看到类似这样的景像——

with geographical features.

有着地理特征。

And now, the complex sugars are these trees and bushes --

复杂的糖蛋白就是 里面的树林和树灌木——

weeping willows that are swaying in the wind

垂柳在风中摇摆，

and moving with the waves.

随波而动。

And when I started thinking about all these complex sugars

当我开始思考 这些复杂的糖蛋白

that are like this foliage on our cells,

就像是我们细胞上的植物时，

it became one of the most interesting problems that I encountered

它成为了作为一个 生物学家和化学家的我

as a biologist and also as a chemist.

所遇到的最有趣的问题之一。

And so now we tend to think about the sugars

现在我们都倾向于将这些

that are populating the surface of our cells

占据我们细胞表层的糖蛋白

as a language.

看成一种语言。

They have a lot of information stored in their complex structures.

有许多的信息都存储在 它们复杂的结构中

But what are they trying to tell us?

但是它们想要告诉我们什么呢？

I can tell you that we do know some information

我可以告诉你我们的确知道

一些来自这些糖蛋白中的信息，

that comes from these sugars,

结果发现这些信息

and it's turned out already to be incredibly important

对医学领域非常重要。

in the world of medicine.

For example, one thing your sugars are telling us

例如，你细胞上的糖蛋白可以揭示

is your blood type.

你们的血型。

So your blood cells, your red blood cells, are coated with sugars,

你的血细胞，红血细胞 都被糖蛋白包裹着，

而这些糖蛋白的化学结构 决定了你的血型。

and the chemical structures of those sugars determine your blood type.

So for example, I know that I am blood type O.

例如，我知道我的血型是O型，

How many people are also blood type O?

在座的有多少人是O型血的？

Put your hands up.

请举起你们的手。

这是一个很常见的血型。

It's a pretty common one,

so when so few hands go up, either you're not paying attention

今天举手的不多， 要么你们没有注意听我说，

要么你们有些人不知道 自己的血型，这都不太好。

or you don't know your blood type, and both of those are bad.

（观众笑声）

(Laughter)

但是对于这些跟我一样 是O型血的人来说，

But for those of you who share the blood type O with me,

what this means is that we have this chemical structure

就意味着在我们血细胞的表层

on the surface of our blood cells:

都有着这样的化学结构：

three simple sugars linked together to make a more complex sugar.

三个单糖连在一起 组成一个更复杂的糖。

And that, by definition, is blood type O.

按照定义，这就是O型血。

Now, how many people are blood type A?

有多少人是A型血的？

Right here.

这里有。

That means you have an enzyme in your cells

那意味着在你的细胞上有一种酶，

that adds one more building block,

又增加了一个成分，

that red sugar,

就是那个红色的单糖，

to build a more complex structure.

形成了一个更加复杂的结构。

And how many people are blood type B?

那么B型血的又有多少人呢？

Quite a few.

还不少。

You have a slightly different enzyme than the A people,

你有一种与A型血的人略有不同的酶，

所以在细胞表面会 形成一种稍有不同的结构。

so you build a slightly different structure,

and those of you that are AB

而那些AB型血的人，

have the enzyme from your mother, the other enzyme from your father,

从父母双方那里 同时获得了这两种酶，

and now you make both of these structures in roughly equal proportions.

形成两种结构，它们大约各占一半。

And when this was figured out,

当这一点被发现以后——

which is now back in the previous century,

也就是上个世纪的事——

this enabled one of the most important medical procedures in the world,

这开启了世界上最重要的医疗手段之一，

which, of course, is the blood transfusion.

那当然就是输血。

And by knowing what your blood type is,

通过知道你的血型，

we can make sure, if you ever need a transfusion,

我们可以在你需要输血的时候

that your donor has the same blood type,

确保献血者跟你是同样的血型。

so that your body doesn't see foreign sugars,

这样你的身体里就不会 出现不同的糖蛋白，

which it wouldn't like and would certainly reject.

也就不会产生排斥。

What else are the sugars on the surface of your cells trying to tell us?

你细胞表层上的糖蛋白 还能告诉我们什么呢？

Well, those sugars might be telling us that you have cancer.

这些糖蛋白还可能告诉我们 你是否得了癌症。

So a few decades ago,

数十年前，

correlations began to emerge from the analysis of tumor tissue.

对肿瘤组织进行分析的关系性 统计数据开始出现。

And the typical scenario is a patient would have a tumor detected,

典型的情况是这样的： 一个病人身上被检测出肿瘤，

and the tissue would be removed in a biopsy procedure

然后从有肿瘤的组织上取得切片，

and then sent down to a pathology lab

送到病理实验室，

where that tissue would be analyzed to look for chemical changes

在那里对这个组织上的 化学变化进行分析，

that might inform the oncologist about the best course of treatment.

以便告知肿瘤医师最好的治疗方案。

And what was discovered from studies like that

而人们从那样的研究中所发现的是，

is that the sugars have changed

当细胞由健康转向病态时，

when the cell transforms from being healthy to being sick.

它表层上的糖蛋白发生了变化。

And those correlations have come up again and again and again.

这些分析关系性 一次又一次的被提出来。

But a big question in the field has been: Why?

但是在这个领域有一个 大的问题，那就是：为什么？

Why do cancers have different sugars? What's the importance of that?

为什么癌变的细胞有不同的糖蛋白？ 它的重要性是什么？

Why does it happen, and what can we do about it if it does turn out

为什么它会发生， 如果结果证明它跟病变过程

to be related to the disease process?

有关联，那么我们又能做些什么？

So, one of the changes that we study

我们研究的这些变化之一

is an increase in the density of a particular sugar

是某种特定糖蛋白 密度的增加，

that's called sialic acid.

这种糖蛋白叫做唾液酸。

And I think this is going to be one of the most important sugars

我觉得它将成为我们这个时代

of our times,

最重要的糖蛋白之一，

so I would encourage everybody to get familiar with this word.

所以我会鼓励大家去熟悉这个词语。

Sialic acid is not the kind of sugar that we eat.

唾液酸不是那种 我们用来吃的糖，

Those are different sugars.

它们是不同的糖。

This is a kind of sugar that is actually found

这是一种在可以在你身体的

at certain levels on all of the cells in your body.

每一个细胞上都能找到的糖蛋白。

It's actually quite common on your cells.

实际上它在你的细胞上中很常见。

But for some reason,

但出于某种原因，

cancer cells, at least in a successful, progressive disease,

癌细胞，至少在一场成功的 进行性的病变中

tend to have more sialic acid

常常比正常、健康的细胞

than a normal, healthy cell would have.

含有更多的唾液酸。

And why?

为什么？

What does that mean?

这意味着什么？

Well, what we've learned

我们所了解到，

is that it has to do with your immune system.

这与你的免疫系统有关。

So let me tell you a little bit about the importance of your immune system

让我给你们再讲一点关于 免疫系统在对抗癌症中的

in cancer.

重要性。

And this is something that's, I think, in the news a lot these days.

我想，这也是目前 在新闻中经常出现的内容。

You know, people are starting to become familiar with the term

人们正在开始熟悉

"cancer immune therapy."

“癌症免疫疗法”这个术语。

And some of you might even know people

你们当中有人可能甚至认识

who are benefiting from these very new ways of treating cancer.

一些从这些非常新的癌症治疗 手段中受益的人。

What we now know is that your immune cells,

我们现在知道是你的免疫细胞，

which are the white blood cells coursing through your bloodstream,

也就是在血流中穿梭的白血细胞

protect you on a daily basis from things gone bad --

在保护我们在日常中免受伤害——

including cancer.

包括癌症。

And so in this picture,

在这张图中，

those little green balls are your immune cells,

这些绿色的小球 是你的免疫细胞，

and that big pink cell is a cancer cell.

粉红色的大球 是一个癌症细胞。

And these immune cells go around and taste all the cells in your body.

这些免疫细胞会四处活动， 尝遍你身上的所有细胞，

That's their job.

那是它们的工作。

And most of the time, the cells taste OK.

而大多数时间， 这些细胞尝起来都没有问题，

But once in a while, a cell might taste bad.

但偶尔会有一个细胞 尝起来不正常。

Hopefully, that's the cancer cell,

希望那就是癌症细胞，

and when those immune cells get the bad taste,

当这些免疫细胞 尝到不正常的细胞时，

they launch an all-out strike and kill those cells.

它们会全力攻击消灭这些细胞。

So we know that.

我们知道这一点。

We also know that if you can potentiate that tasting,

我们还知道如果 你能强化这种品尝，

if you can encourage those immune cells to actually take a big old bite

如果你能鼓励这些免疫细胞

out of a cancer cell,

去大力吞噬一个癌细胞，

you get a better job protecting yourself from cancer every day

你就可以更好的保护自己 免受癌症的侵扰，

and maybe even curing a cancer.

甚至还有可能治愈癌症。

And there are now a couple of drugs out there in the market

现在市场上有一些

that are used to treat cancer patients

治疗癌症的药，

that act exactly by this process.

正是通过这个过程起作用的。

They activate the immune system

它们能够激活免疫系统，

so that the immune system can be more vigorous

使免疫系统在保护我们不受癌症侵扰时

in protecting us from cancer.

更加的有活力。

In fact, one of those drugs

事实上，这些药物中的一种

may well have spared President Jimmy Carter's life.

可能已经延长了前总统 吉米·卡特的生命。

Do you remember, President Carter had malignant melanoma

你们记得吗，卡特总统 患有恶性黑色素瘤，

that had metastasized to his brain,

并且癌细胞转移到了脑部

and that diagnosis is one that is usually accompanied by numbers

而那种诊断通常还伴有

like "months to live."

“只剩下几个月了”这样的描述。

But he was treated with one of these new immune-stimulating drugs,

但是他使用了一种 免疫刺激类的药物，

and now his melanoma appears to be in remission,

现在他的癌症出现了好转，

which is remarkable,

跟几年前情况相比

considering the situation only a few years ago.

这是非常了不起的。

In fact, it's so remarkable

正因为这样非凡的进步，

that provocative statements like this one:

所以出现了一些豪言壮志：

"Cancer is having a penicillin moment," people are saying,

“有了这些新的免疫疗法药物，

癌症正在被消灭。”

with these new immune therapy drugs.

我的意思是，对于一个我们已经与之

I mean, that's an incredibly bold thing to say about a disease

which we've been fighting for a long time

斗争了很长时间， 并以失败居多的疾病而言

and mostly losing the battle with.

说出这样的话是一件很有勇气的事。

So this is very exciting.

这是非常令人激动的。

Now what does this have to do with sugars?

那么这又跟糖蛋白有什么关系呢？

Well, I'll tell you what we've learned.

下面我就会告诉你们我们的发现。

When an immune cell snuggles up against a cancer cell to take a taste,

当一个免疫细胞裹住 一个癌细胞去尝它时，

it's looking for signs of disease,

它是在寻找疾病的信号，

and if it finds those signs,

如果它发现了这些信号，

the cell gets activated and it launches a missile strike and kills the cell.

那么它就会被激活， 并发起猛烈的攻击去消灭癌细胞。

But if that cancer cell has a dense forest of that sugar, sialic acid,

但是如果癌细胞拥有丰富的 那种糖蛋白，唾液酸，

well, it starts to taste pretty good.

那么它会尝起来很好。

And there's a protein on immune cells that grabs the sialic acid,

免疫细胞中有一种蛋白质 可以抓取唾液酸，

and if that protein gets held at that synapse

如果这种蛋白质被困在

between the immune cell and the cancer cell,

免疫细胞和癌细胞之间的突触中，

it puts that immune cell to sleep.

就会使得免疫细胞进入休眠状态。

The sialic acids are telling the immune cell,

唾液酸在告诉免疫细胞，

"Hey, this cell's all right. Nothing to see here, move along.

“这个细胞没问题， 这里没有什么，继续往前走，

Look somewhere else."

去其它地方看看吧。”

So in other words,

换句话说，

as long as our cells are wearing a thick coat of sialic acid,

只要我们的细胞被一层 厚厚的唾液酸包裹着，

they look fabulous, right?

它们看起来就是极好的，对吧？

It's amazing.

真的很神奇。

And what if you could strip off that coat

如果你能剥开这层外衣，

and take that sugar away?

除去那些糖蛋白会怎么样？

Well, your immune system

那么你的免疫系统

might be able to see that cancer cell for what it really is:

也许会看到癌细胞的真面目：

something that needs to be destroyed.

这是一些需要被消灭的家伙。

And so this is what we're doing in my lab.

而这也是我们正在实验室里 所进行的研究。

We're developing new medicines

我们正在研发新药，

that are basically cell-surface lawnmowers --

相当于是细胞表层的割草机——

molecules that go down to the surface of these cancer cells

让药物微粒进入癌细胞表层，

and just cut off those sialic acids,

除去这些唾液酸，

so that the immune system can reach its full potential

这样就能让免疫系统 发挥全部潜能，

in eliminating those cancer cells from our body.

消灭我们体内的癌细胞。

So in closing,

最后，

let me just remind you again:

让我再提醒你们一次：

your cells are coated with sugars.

你的细胞被糖蛋白包裹着。

The sugars are telling cells around that cell

这些糖蛋白可以告诉 这个细胞周围的其它细胞

whether the cell is good or bad.

这个细胞是好还是坏。

And that's important,

而这是非常重要的，

because our immune system needs to leave the good cells alone.

因为我们需要免疫系统 不要去打扰正常的细胞，

Otherwise, we'd have autoimmune diseases.

否则我们就会患上 自身免疫系统疾病。

But once in a while, cancers get the ability

但是有时癌症会获得

to express these new sugars.

表达这些新糖蛋白的能力，

And now that we understand

我们现在知道

how those sugars mesmerize the immune system,

这些糖蛋白是如何记住免疫系统的，

we can come up with new medicines to wake up those immune cells,

可以由此研发出新药 去唤醒这些免疫细胞，

tell them, "Ignore the sugars, eat the cell

告诉它们，“别管这些糖蛋白， 吞掉这些癌细胞，

and have a delicious snack, on cancer."

享受这些可口的小吃。”

Thank you.

谢谢。

(Applause)

（观众掌声）