What If a Simple Blood Test Could Detect Cancer? | Hani Goodarzi | TED

譯者: Ch'ng Tsu Pang 審譯者: Shelley Tsang 曾雯海

Catching cancer at its earliest stages,

及早發現癌症，可以拯救無數生命。

when it's most treatable, can save countless lives.

因為癌症在初期的時候最易治療。

But the million-dollar question is:

但一個關鍵的問題是：

in an otherwise healthy body made up of trillions of cells,

一個健康的人體內會有數萬億個細胞，

how can we zero in on a small group of rogue cancer cells?

我們怎樣才能找到那一小部分 異常的癌細胞呢？

The answer, I think,

我認為，

may be rooted in something that, thanks to the pandemic,

有一樣東西或許可以幫我們找到答案。

we have all come to know quite well, and that is RNA.

這東西因疫情而廣為人知， 那就是核糖核酸，也就是RNA。

I think these days, everyone has a basic understanding of how RNA works.

我認為如今我們每個人 對RNA的功能都有了一些基本的瞭解。

Again, thanks to the COVID vaccines.

這也是多虧了COVID疫苗。

But basically, RNA is transcribed from DNA in the cell,

簡單來說，RNA是 由細胞中的DNA轉錄而成的。

and messenger RNA specifically serves as a template for protein synthesis.

而信使RNA（mRNA）則是專門 用於合成蛋白質的模板。

So usually the more mRNA you have in the cell,

一般來說，你细胞中的mRNA越多，

the more protein you get.

你身上的蛋白質就越多。

But our discovery is a little bit different.

但我們的發現卻有些不同。

We have found a new class of RNAs

我們發現了一個全新的RNA類別，

that have changed how we think about cancer detection.

它改變了我們對癌症檢測的認知思路。

These are relatively small RNAs,

它們是相對較小的RNA，

and they don't actually code for any protein.

所以不負責編碼任何蛋白質，

So they're non-coding.

因此被歸類為非编码RNA。

And since we found them, we got to name them.

既然細胞是我們發現的， 當然由我們來給它命名。

And we have called them orphan non-coding RNAs

我們稱他們為 “孤兒非編碼 RNA”，

or oncRNAs for short.

簡稱 oncRNA。

These oncRNAs have not only changed

這些oncRNA不僅改變了

and transformed our approach to cancer detection

我們檢測癌症的方法，

from blood non-invasively,

讓我們能通過非侵入性驗血 來檢測癌症，

but they've also helped open a window into the tumor itself for us.

也為我們打開了 一扇瞭解癌症腫瘤的窗口。

So leveraging these RNAs,

利用這種RNA，

we are not only detecting cancer earlier,

我們不但可以更早地發現癌症，

we are actually peering into its biology.

也能窺見其中的生物學原理。

So with that short introduction, let me break down the science for you.

好，經過以上簡短的介紹過後， 請允許我解釋一下這背後的原理。

As you may know, every cell in our body shares the same genetic code

大家可能知道，我們身體內的 每個細胞都和其他所有細胞

as every other cell.

擁有同樣的基因信息。

It's as if our cells have access to the same pantry,

這就好比我們所有細胞 都能出入同一個厨房，

but then they use different recipes

使用同樣的食材，但卻用不同的食譜

to mix the same ingredients into different dishes.

煮出不同的菜餚。

It's actually the diversity in genomic recipes

而實際上正是因爲 我們的基因食譜種類繁多，

that gives us the more than 200 cell types we have in our bodies,

我們的身體才能夠 產生 200 多種不同的細胞。

each with their own distinct role and function,

每種細胞 都有自己專屬的功能和作用，

like skin cells, for example, or neurons.

比如皮膚細胞，或神經元。

And as you can imagine,

想象一下，在你的細胞內

there is a complex machinery in place in the cell that governs this process

有一個複雜的機制在控制整個過程。

and tells the cell for each of its 20,000 genes

它負責告诉细胞該如何處理

how much of them it needs to express

自身20,000多個基因的表達，

to be a healthy, well-functioning cell.

從而組成一個健康的、功能健全的細胞。

Now, cancer cells, being the resourceful survivalists that they are,

反觀癌細胞 這機靈善變的生存高手，

they actually hijack components of this machinery to their advantage.

他們会為了自身利益 而劫持這個機器的部件。

And they do this to increase the expression of genes

它們這樣做 一方面是為了增加一些基因的表达，

that will help the tumor grow and spread throughout the body,

促進腫瘤在全身的生長和擴散；

or silence or down-regulate genes whose job is to keep cancer in check.

一方面則會抑製或下調 那些負責抑制癌細胞的基因。

Another way of putting this

換一種說法，

癌細胞本質上是在破解

is that cancer cells are basically hacking that original genomic recipe

that I told you about.

之前提過的原始基因配方。

Now a few years ago, we made an interesting discovery

不過，幾年前， 我們有了一個有趣的發現。

that is actually a consequence of this genomic reprogramming

我們發現了癌細胞破解基因後 所帶來的一個後果。

that happens in cancer cells, is actually a hallmark of cancer.

而這個後果，實際上是癌症的特徵。

Basically, parts of the genome that is normally silent

簡單來講，基因組中 通常處於沈默狀態

and inactive in healthy cells

且在健康細胞中無活性的部分

becomes activated in cancer.

會因癌症而被激活。

And a direct consequence of this activation

這部分被激活後，

is the birth of a new kind of RNA.

細胞內會誕生一種全新的RNA。

That we only see these RNAs in cancer,

這些RNA只在癌症中出現，

but not really in healthy cells.

健康的細胞中則不會有。

Now over the past few years,

在過去的幾年裡，

we have spent a lot of time basically mapping these cancer-emergent RNAs

我們投入了大量時間定位癌細胞RNA， 找出他們分別從

across human cancers.

哪些人類癌細胞產生。

And as I told you earlier,

正如我之前所說的，

we have come to name them oncRNAs.

我們已將它們命名為oncRNA。

Now, what is even more interesting

更有趣的是，我發現

is that which oncRNAs I see in a given sample is not random.

樣本中的oncRNA不是隨機出現的。

It's actually tied back to the type or subtype of cancer

它其實和我正在研究的癌症類型

that I'm looking at.

以及其亞型密切相关。

So collectively, oncRNAs actually provide a digital molecular barcode

綜上所述，oncRNA實際上很像是

that captures cancer cell identity.

一種記錄癌細胞身份的分子條碼。

And it's actually unique to the type or subtype of cancer.

每種癌症及其亞型 都會對應不同的分子條碼。

But how are these molecular barcodes actually useful?

但這些分子條碼到底有什麼用處呢？

So it turns out oncRNAs are not actually confined to cancer cells.

其實，oncRNA不只出現在癌細胞裡，

Some of them are nicely packaged and released into the blood.

有些oncRNA會被包裝好， 再釋放到细胞外的血液當中。

And this is something that healthy cells do as well with other small RNAs.

健康的细胞也經常这样处理 小型RNA。

And with all of this introduction, I hope you know where I'm going with this.

說到這裏， 希望妳們能理解前面層層鋪墊的意義。

Basically, if oncRNAs are only expressed in cancer cells,

簡單來說，如果這些oncRNA 只有癌细胞才會表達，

and some of them do in fact find their way into the bloodstream,

而且有一部分也確實會混入血液當中，

doesn't it mean that we should be able to detect them

那麽我們豈不是可以從 癌症患者的血液樣本中

in blood samples from cancer patients?

檢測出oncRNA嗎？

The answer, turns out, is yes, but with an asterisk.

正如我們研究顯示，答案是肯定的， 但問題沒有這麼簡單。

So the oncRNAs that we detect in blood samples from patients

經測試，我們在患者血液樣本中 所檢測到的oncRNA

actually form a partial barcode.

其實只是「條碼」的一部分。

And it's only a partial barcode

之所以說這只是部分條碼，

because only a subset of oncRNAs

是因為只有一部分oncRNA

are actually secreted from cancer cells into the blood.

會從癌細胞分泌到血液中。

And even a smaller subset can be reliably detected

而在少量血液中，

in a small volume of blood.

我們能夠精准檢測到的oncRNA則更少。

However, thanks to the magic of machine learning and AI,

不過，多虧了神奇的 機器學習和人工智能，

we can actually use this partial information

我們能夠利用這些有限的信息，

to reconstruct the original barcode that resides in the tumor.

重建癌症腫瘤內原本的條碼。

And we can match that deconstruction

此外，我們還可以將條碼碎片

against our catalog of oncRNA barcodes across cancers

與我們的oncRNA條碼目錄 進行對比。

to not only --

這麼一來，

to not only detect the presence of the disease,

我們不僅可以檢測到癌细胞的存在，

but also identify its type or subtype.

還可以識別其類型或亞型。

And actually, as we grow,

事實上，隨著這方面的研究趨於完善，

fundamentally increase the number of these oncRNA catalogs that we have built,

oncRNA的目錄也會越來越豐富。

we can go deeper and deeper into the biology of the disease as well.

我們也能夠更深入地研究 癌症背後的原理。

Now, with help from our clinical collaborators at UCSF,

目前，有了加州大學舊金山分校 臨床合作者的帮助，

we have come a step closer to actually bringing this platform to the clinic.

將這項技術應用於臨床診斷 的目標將更容易實現。

In a preliminary study across 200 breast cancer patients,

在一項針對 200名乳腺癌患者的 初步研究中,

we have actually shown that we can use oncRNAs

我們成功證明了 我們可以利用oncRNA

來檢測患者在接受治療後，

to detect residual disease in patients

after they have received treatment,

體内殘余的細胞。

and knowing which patients have remaining disease,

而知道哪些病人體内仍殘留癌细胞後，

tells clinicians who needs additional treatment or monitoring

我們就能告訴臨床醫師， 誰需要在手術後

after the surgery.

接受進一步治療或監測。

And this way, patients receive more treatment

這樣一來，有需要的病人們才能

only when it's needed.

得到及時的治療。

I truly believe that the next decade is the decade of cancer screening.

我堅信，未來十年 是癌症篩查技術發展的重要十年。

And as you can imagine, blood detection of cancers

可想而知，通過血液檢測來診斷癌症

is a major frontier in that war.

將是戰勝這場戰爭的關鍵。

And I hope to have convinced you today that leveraging powerful AI

至此，我希望今天的演講 已經讓你相信，

built on top of molecular barcodes of oncRNAs,

在oncRNA分子條形碼的基礎上 善用人工智能，

we can envision a future that’s precise and sensitive,

我們可以展望，未來的癌症檢測 不僅是高準確度、高靈敏度的，

but more importantly,

更重要的是，

very accessible.

這檢測將極爲方便。

Blood detection of cancers is not just the hope,

通過血液檢測癌症 將不會是奢望，

but it's actually a reality.

而是現實。

Thank you.

謝謝大家。

(Applause)

（掌聲）