Using fluorescence to expose cancer | Cédric Enguehard | TEDxLimoges
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0:12 - 0:15A few years ago, Limoges university
hospital practitioners -
0:15 - 0:17and Faculty of Medicine researchers
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0:17 - 0:18were in discussion.
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0:18 - 0:20And they wanted to know
if there was something -
0:20 - 0:23that might aid them
during cancer surgeries. -
0:23 - 0:25What they found
did not really satisfy them. -
0:25 - 0:28So, they straightway
launched a research program. -
0:29 - 0:30This research involved medics,
-
0:30 - 0:33researchers in biology,
in chemistry, physicists, -
0:33 - 0:36from various institutes,
and from various organizations. -
0:37 - 0:40The first time I heard
of this research program and its work, -
0:40 - 0:44I was right away attracted by the elegance
of the solution it proposed. -
0:44 - 0:45And then I saw very quickly
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0:45 - 0:49the incredible impact
this technology could have for patients. -
0:49 - 0:53So I decided to quit my job to dedicate
all of my time to this project, -
0:53 - 0:56and I was joined by two friends,
Alexis and Virgile. -
0:56 - 0:57Today, we are trying to transform
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0:57 - 1:00this beautiful technology
into a real tool. -
1:00 - 1:03So, how can we see what is not visible?
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1:04 - 1:06Most of what surrounds us
that we call invisible -
1:06 - 1:09is just too small for us to perceive.
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1:09 - 1:13It's the case, for example, in diseases
that we cannot see directly. -
1:13 - 1:17What we can see are the symptoms
that inform us that something is wrong. -
1:21 - 1:24Certain diseases come
from external factors -
1:24 - 1:26like viruses or, say, bacteria.
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1:26 - 1:29Other illnesses come from our own body.
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1:29 - 1:30That's the case for cancer.
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1:31 - 1:34Throughout our life,
right now as I am talking to you, -
1:34 - 1:38all of us, we all have cells
that regenerate and renew themselves -
1:38 - 1:42in a cycle that we might consider
to be birth, life, and death. -
1:42 - 1:43All this at the cellular level.
-
1:44 - 1:48For example, the liver renews
all of its cells in 400 days. -
1:48 - 1:51This is not an excuse
for your next night out - -
1:52 - 1:54you will agree.
-
1:54 - 1:56And some other cells
are renewed even faster. -
1:56 - 1:58That's the case for the intestine.
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1:58 - 2:01The intestine renews its cells
entirely every five days. -
2:01 - 2:04And during our entire life,
we are all going to lose -
2:04 - 2:06about the equivalent
of 20 kg of dead skin. -
2:07 - 2:09Think about that
when you see dust at home. -
2:12 - 2:17Unfortunately, in this process,
some cells may degenerate. -
2:17 - 2:19This can have several causes:
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2:19 - 2:24our lifestyle, inherited factors,
or our environment. -
2:25 - 2:27And these cells will start to degenerate.
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2:27 - 2:30For example, some of them
will become immortal. -
2:30 - 2:33When I first heard
some cells become immortal, -
2:33 - 2:35I thought we were all going to live long.
-
2:35 - 2:38In fact, no, it just brings
processes to a complete end, -
2:38 - 2:41with the consequence
that the organ becomes non-functional. -
2:42 - 2:46So, at the root of a disease as serious,
as terrible, as cancer, -
2:46 - 2:48there are just tiny cells.
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2:48 - 2:51And a cell measures about 10 micrometres,
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2:52 - 2:55which is nearly 10 times smaller
than the diameter of a hair. -
3:01 - 3:03It is really small.
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3:03 - 3:08(Applause)
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3:10 - 3:12They are tiny, and cannot be seen
with the naked eye. -
3:12 - 3:15They also have an incredible quality
that is really vicious, -
3:15 - 3:18which is that they make themselves
invisible to our immune system, -
3:18 - 3:21and so our body cannot
defend itself against them. -
3:22 - 3:26There are different methods
to discover cancerous lesions. -
3:26 - 3:29For example, tumour marking:
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3:29 - 3:30We take a sample, we mark it,
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3:30 - 3:32and we get to detecting lesions
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3:32 - 3:34of several tens of thousands
of cancerous cells. -
3:34 - 3:36There's also imaging.
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3:36 - 3:37We inject a tracer into the patient,
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3:37 - 3:41use a device like
a PET scanner or a scintigraph, -
3:41 - 3:44and we can see lesions
of a few millimetres in size. -
3:44 - 3:47But already, the cancer
consists of tens of millions, -
3:47 - 3:49even hundreds of millions, of cells.
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3:49 - 3:51For a tumour to be
visible to the naked eye, -
3:51 - 3:53when it's nearly a centimetre across,
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3:53 - 3:55we're into hundreds of millions of cells,
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3:55 - 3:56even billions.
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3:58 - 4:00During the life of the patient,
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4:00 - 4:04most of these cancers are going
to be treated by surgical means. -
4:04 - 4:07That is, a man or a woman
will go to this organ, -
4:07 - 4:11which she or he knows is sick,
and will remove the tumour cells. -
4:11 - 4:14But at some point, despite
all their expertise and experience, -
4:14 - 4:16they'll need to ask themselves:
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4:16 - 4:18Should I continue
to scrape away at this organ? -
4:18 - 4:22Should I continue to remove
a small part of this organ? -
4:22 - 4:26If I continue, I may remove
some healthy, functional tissue, -
4:26 - 4:29and I may thus compromise
my patient's quality of life. -
4:29 - 4:33That's very clear when it's about
lesions in the brain, for example. -
4:33 - 4:36On the other hand, if I stop,
if I leave it as it is, -
4:36 - 4:39I take the risk of there
remaining cancer cells, -
4:39 - 4:42and then the cancer
may come back and re-advance. -
4:42 - 4:44It is precisely to see
the invisible boundary -
4:44 - 4:47between healthy cells
and those that are cancerous -
4:47 - 4:48that this project was started.
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4:49 - 4:51Imagine a cell.
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4:52 - 4:53So here, clearly, I shrank.
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4:54 - 4:57On this cell, there are
lots of tiny molecules. -
4:57 - 4:59These small molecules, all different,
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4:59 - 5:02can tell us about the internal functioning
and mechanism of the cell. -
5:03 - 5:07So, all we have to do is find the molecule
that tells us the cell is cancerous, -
5:07 - 5:09and we're there.
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5:09 - 5:12In biology, there are antibodies -
you've already heard about them - -
5:12 - 5:14and antibodies know how to do many things,
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5:14 - 5:18in particular, to recognize
and hook onto these molecules. -
5:18 - 5:21And onto our antibody,
we can hook a fluorophore, -
5:21 - 5:23a type of biological lantern
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5:23 - 5:25that re-emits light
when light is shone on it. -
5:25 - 5:28So, we attach this fluorophore
to our antibody, -
5:28 - 5:31and the moment our antibody
hooks onto the molecule, -
5:31 - 5:33it will signal to us
that that one is cancerous. -
5:33 - 5:35This is already a very big step.
-
5:35 - 5:37But they went even further
in their research. -
5:37 - 5:41It so happens that when the antibody
hooks its molecule, it changes shape, -
5:41 - 5:44it's as if it folds its arms.
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5:44 - 5:48And this is great because there is
another physical effect called FRET - -
5:48 - 5:50Förster Resonance Energy Transfer.
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5:50 - 5:52I feel like I've lost you all.
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5:52 - 5:56This superb effect - it's quite easy
to understand, but it's incredible. -
5:56 - 6:00You have two fluorophores,
of different colours, one red, one green. -
6:00 - 6:01Each shines in its place,
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6:01 - 6:04but at a given moment,
at a really precise distance, -
6:04 - 6:08they will exchange their energy,
one will transfer its energy to the other. -
6:08 - 6:11And so our green fluorophore
begins to become dimmer, -
6:11 - 6:14while the red fluorophore
begins to become much more intense. -
6:15 - 6:18The idea behind it was
to take these two fluorophores, -
6:18 - 6:21hook them to very specific
places on our antibody, -
6:21 - 6:24so that when it recognizes
a cancerous cell, -
6:24 - 6:26by hooking onto it, it will change colour.
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6:27 - 6:29So, instead of seeing light
slightly green and red, -
6:29 - 6:31the surgeon will only see red light,
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6:31 - 6:35telling her or him that she or he
should continue to perform their surgery. -
6:35 - 6:38But to go even further,
we took these small antibodies -
6:38 - 6:41and put them at the end of a small
optical fibre about 2 mm in diameter, -
6:41 - 6:44to come directly into contact
with the patient's tissue. -
6:44 - 6:46By injecting a light beam,
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6:46 - 6:49we are able to tell whether or not
the tissues are cancerous, -
6:49 - 6:52whether or not to continue
to perform the surgery -
6:52 - 6:54to give the patient the best chance.
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6:54 - 6:56It's thanks to this project
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6:56 - 6:58that we can improve
the patient's quality of life -
6:58 - 7:02by making detectable what was invisible.
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7:02 - 7:03Thank you.
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7:03 - 7:06(Applause)
- Title:
- Using fluorescence to expose cancer | Cédric Enguehard | TEDxLimoges
- Description:
-
Bad, good; the boundary is sometimes hard to determine.
When the disease is in our tissues, shedding light on this boundary becomes a vital matter. Open the directory of dysfunctions of the human body, an encyclopedia, one needs to choose a cause. For this speaker, it was to be to separate what is well from what is not.
A former student at the University of Limoges and a doctorate from the XLIM laboratory, previously at AMCAD Engineering, Cédric Enguehard is one who seeks out, and his business creation has one mission: to arm medical science against that invisible malignancy that makes diagnosis difficult. To eliminate guesswork from interpretation: to bring out, to determinedly distinguish, to demarcate, what is clearly bad. If we're going to cut the grass, we might as well cut it as short as possible under the feet of the Grim Reaper.
This talk was given at a TEDx event using the TED conference format but independently organized by a local community. Learn more at http://ted.com/tedx
- Video Language:
- French
- Team:
- closed TED
- Project:
- TEDxTalks
- Duration:
- 07:18
Robert Tucker approved English subtitles for La fluorescence pour débusquer le cancer | Cédric ENGUEHARD | TEDxLimoges | ||
Robert Tucker edited English subtitles for La fluorescence pour débusquer le cancer | Cédric ENGUEHARD | TEDxLimoges | ||
Robert Tucker edited English subtitles for La fluorescence pour débusquer le cancer | Cédric ENGUEHARD | TEDxLimoges | ||
Robert Tucker edited English subtitles for La fluorescence pour débusquer le cancer | Cédric ENGUEHARD | TEDxLimoges | ||
Robert Tucker edited English subtitles for La fluorescence pour débusquer le cancer | Cédric ENGUEHARD | TEDxLimoges | ||
Robert Tucker accepted English subtitles for La fluorescence pour débusquer le cancer | Cédric ENGUEHARD | TEDxLimoges | ||
Robert Tucker edited English subtitles for La fluorescence pour débusquer le cancer | Cédric ENGUEHARD | TEDxLimoges | ||
Robert Tucker edited English subtitles for La fluorescence pour débusquer le cancer | Cédric ENGUEHARD | TEDxLimoges |