well hello it’s great to be here I’m going to tell you a story today that
going to tell you a story today that
going to tell you a story today that intersects my life in brain surgery
intersects my life in brain surgery
intersects my life in brain surgery neural stem cells and brain cancer and I
neural stem cells and brain cancer and I
neural stem cells and brain cancer and I call it beyond brain surgery and I think
call it beyond brain surgery and I think
call it beyond brain surgery and I think beyond brain surgery is science and
beyond brain surgery is science and
beyond brain surgery is science and biology and that’s the future in my
biology and that’s the future in my
biology and that’s the future in my daily work I get to see the human the
daily work I get to see the human the
daily work I get to see the human the live human brain almost every day and
live human brain almost every day and
live human brain almost every day and every day I’m absolutely marveled at how
every day I’m absolutely marveled at how
every day I’m absolutely marveled at how this tan-colored three-pound organ
dictates and is embedded within our
dictates and is embedded within our feelings our emotions our skills our
feelings our emotions our skills our
feelings our emotions our skills our knowledge how is it that biological
knowledge how is it that biological
knowledge how is it that biological pulsating tissue can be the essence of
pulsating tissue can be the essence of
pulsating tissue can be the essence of who we are and certainly I love this
who we are and certainly I love this
who we are and certainly I love this quote from this physicist this
quote from this physicist this
quote from this physicist this theoretical physicist from the US who
theoretical physicist from the US who
theoretical physicist from the US who says who says the human brain is a
says who says the human brain is a
says who says the human brain is a hundred billion neurons each neuron
hundred billion neurons each neuron
hundred billion neurons each neuron connected to 10,000 other neurons and
connected to 10,000 other neurons and
connected to 10,000 other neurons and and sitting on your shoulders is the
and sitting on your shoulders is the
and sitting on your shoulders is the most complicated object in the known
most complicated object in the known
most complicated object in the known universe just the complexity of the
universe just the complexity of the
universe just the complexity of the human brain is absolutely astounding and
human brain is absolutely astounding and
human brain is absolutely astounding and 200 years ago we had a simple view of
200 years ago we had a simple view of
200 years ago we had a simple view of what was going on the brain based on
what was going on the brain based on
what was going on the brain based on examination of patience and
examination of patience and
examination of patience and understanding of cos that affected them
understanding of cos that affected them
understanding of cos that affected them and affected their functions and then
and affected their functions and then
and affected their functions and then studying their brains after to see which
studying their brains after to see which
studying their brains after to see which which regions were involved and so we
which regions were involved and so we
which regions were involved and so we had this map for for movement of
had this map for for movement of
had this map for for movement of different parts of the body and
different parts of the body and
different parts of the body and different areas of feeling but now with
different areas of feeling but now with
different areas of feeling but now with functional MRI with diffusion tensor
functional MRI with diffusion tensor
functional MRI with diffusion tensor imaging we have an exquisite map of we
imaging we have an exquisite map of we
imaging we have an exquisite map of we can obtain an exquisite map for every
can obtain an exquisite map for every
can obtain an exquisite map for every person’s brain and it’s not that a text
person’s brain and it’s not that a text
person’s brain and it’s not that a text book can’t tell the story of each
book can’t tell the story of each
book can’t tell the story of each person’s brain we need to actually write
person’s brain we need to actually write
person’s brain we need to actually write a text book for each individual person’s
a text book for each individual person’s
a text book for each individual person’s brain and here you can see all the
brain and here you can see all the
brain and here you can see all the different bundles of nerves that are can
different bundles of nerves that are can
different bundles of nerves that are can interconnecting throughout a human brain
interconnecting throughout a human brain
interconnecting throughout a human brain and as well Jeffrey Lichtman from
and as well Jeffrey Lichtman from
and as well Jeffrey Lichtman from Harvard University has devised a method
Harvard University has devised a method
Harvard University has devised a method in animals where he can label individual
in animals where he can label individual
in animals where he can label individual neurons with different colors to study
neurons with different colors to study
neurons with different colors to study the the cell the cell connectivity of
the the cell the cell connectivity of
the the cell the cell connectivity of the of the brain and certainly these
the of the brain and certainly these
the of the brain and certainly these approaches will come to humans in the
approaches will come to humans in the
approaches will come to humans in the future but this is changing the way we
future but this is changing the way we
future but this is changing the way we think about how these different circuits
think about how these different circuits
think about how these different circuits define the essence of who we are and how
define the essence of who we are and how
define the essence of who we are and how we function now as a neurosurgeon we’re
we function now as a neurosurgeon we’re
we function now as a neurosurgeon we’re not we’re not quite at the cellular
not we’re not quite at the cellular
not we’re not quite at the cellular level but certainly these advances in
level but certainly these advances in
level but certainly these advances in technology are enabling us to do brain
technology are enabling us to do brain
technology are enabling us to do brain surgery safer than we’ve ever been able
surgery safer than we’ve ever been able
surgery safer than we’ve ever been able to do before and we can take this
to do before and we can take this
to do before and we can take this information not just the anatomy not
information not just the anatomy not
information not just the anatomy not just the shape of the brain but we can
just the shape of the brain but we can
just the shape of the brain but we can take these maps of the different
take these maps of the different
take these maps of the different functions for these four for example we
functions for these four for example we
functions for these four for example we can take language and we can pinpoint
can take language and we can pinpoint
can take language and we can pinpoint where language is in the brain so we
where language is in the brain so we
where language is in the brain so we know if we have a lesion to remove in
know if we have a lesion to remove in
know if we have a lesion to remove in the brain we can go around the language
the brain we can go around the language
the brain we can go around the language area to remove the lesion and keep the
area to remove the lesion and keep the
area to remove the lesion and keep the person’s language functions intact and
person’s language functions intact and
person’s language functions intact and we can integrate this with computer
we can integrate this with computer
we can integrate this with computer systems so when we’re doing surgery we
systems so when we’re doing surgery we
systems so when we’re doing surgery we can point to areas in the head or in the
can point to areas in the head or in the
can point to areas in the head or in the brain that tell us exactly where we are
brain that tell us exactly where we are
brain that tell us exactly where we are with respect to the imaging and the
with respect to the imaging and the
with respect to the imaging and the different functional pathways that we
different functional pathways that we
different functional pathways that we want to protect and preserve and so
want to protect and preserve and so
want to protect and preserve and so here’s here’s us we were pointing at the
here’s here’s us we were pointing at the
here’s here’s us we were pointing at the brain in that patient and this tells us
brain in that patient and this tells us
brain in that patient and this tells us relative to the scan where we are and
relative to the scan where we are and
relative to the scan where we are and here just at the bottom left is a tumor
here just at the bottom left is a tumor
here just at the bottom left is a tumor deep in this person’s brain that we’re
deep in this person’s brain that we’re
deep in this person’s brain that we’re seeking to remove and so this is
seeking to remove and so this is
seeking to remove and so this is incredible technology it’s advancing all
incredible technology it’s advancing all
incredible technology it’s advancing all the time it’s allowing us to to devise
the time it’s allowing us to to devise
the time it’s allowing us to to devise safe and better access to make brain
safe and better access to make brain
safe and better access to make brain surgery a safer and safer and and as
surgery a safer and safer and and as
surgery a safer and safer and and as well we have microscopes that allow us
well we have microscopes that allow us
well we have microscopes that allow us to operate at at a millimeter by
to operate at at a millimeter by
to operate at at a millimeter by millimeter level so I could spend four
millimeter level so I could spend four
millimeter level so I could spend four hours in an area the size of the end of
hours in an area the size of the end of
hours in an area the size of the end of my thumb to remove a tumor for example
my thumb to remove a tumor for example
my thumb to remove a tumor for example and and carefully tease it away from
and and carefully tease it away from
and and carefully tease it away from from nerves that might be responsible
from nerves that might be responsible
from nerves that might be responsible for
for
for a person swallowing or their ability to
a person swallowing or their ability to
a person swallowing or their ability to speak for example so all of these tools
speak for example so all of these tools
speak for example so all of these tools we have now at our disposal some brain
we have now at our disposal some brain
we have now at our disposal some brain surgery has never been safer and so it
surgery has never been safer and so it
surgery has never been safer and so it allows us to confront a very difficult
allows us to confront a very difficult
allows us to confront a very difficult problem like this with some confidence
problem like this with some confidence
problem like this with some confidence so here this this was a six year old
so here this this was a six year old
so here this this was a six year old girl who had headaches she gets a scan
girl who had headaches she gets a scan
girl who had headaches she gets a scan and she had this as you can see in the
and she had this as you can see in the
and she had this as you can see in the middle that bright areas is a brain
middle that bright areas is a brain
middle that bright areas is a brain tumor within within the very deepest
tumor within within the very deepest
tumor within within the very deepest reaches of her brain and so we had a
reaches of her brain and so we had a
reaches of her brain and so we had a real challenge how do we get to that
real challenge how do we get to that
real challenge how do we get to that this needs to be removed she’s suffering
this needs to be removed she’s suffering
this needs to be removed she’s suffering symptoms and so with those tools with
symptoms and so with those tools with
symptoms and so with those tools with those maps we were able to sneak in in
those maps we were able to sneak in in
those maps we were able to sneak in in between the two halves of the brain and
between the two halves of the brain and
between the two halves of the brain and minimally disrupt the brain so as to
minimally disrupt the brain so as to
minimally disrupt the brain so as to remove that person that person’s tumor
remove that person that person’s tumor
remove that person that person’s tumor and they woke up beautifully after the
and they woke up beautifully after the
and they woke up beautifully after the operation and everyone was relieved and
operation and everyone was relieved and
operation and everyone was relieved and we were all feeling very good about what
we were all feeling very good about what
we were all feeling very good about what we were able to do with our hands with
we were able to do with our hands with
we were able to do with our hands with this great technology but the problem
this great technology but the problem
this great technology but the problem with brain tumors is this is that they
with brain tumors is this is that they
with brain tumors is this is that they come back and so unfortunately this
come back and so unfortunately this
come back and so unfortunately this person’s tumor came back several years
person’s tumor came back several years
person’s tumor came back several years later and it came back in a way that
later and it came back in a way that
later and it came back in a way that surgery no longer had a role and so
surgery no longer had a role and so
surgery no longer had a role and so first as a as a clinician and with this
first as a as a clinician and with this
first as a as a clinician and with this knowledge cancer is a leading cause of
knowledge cancer is a leading cause of
knowledge cancer is a leading cause of non accidental death and Canadian and
non accidental death and Canadian and
non accidental death and Canadian and American children and brain tumors
American children and brain tumors
American children and brain tumors represent many of these because other
represent many of these because other
represent many of these because other types of childhood cancers are being
types of childhood cancers are being
types of childhood cancers are being cured at a much higher rate for example
cured at a much higher rate for example
cured at a much higher rate for example childhood leukemia and so for myself
childhood leukemia and so for myself
childhood leukemia and so for myself being a brain surgeon and seeing wanting
being a brain surgeon and seeing wanting
being a brain surgeon and seeing wanting to always push myself to do better and
to always push myself to do better and
to always push myself to do better and to go beyond what I’d been taught I I
to go beyond what I’d been taught I I
to go beyond what I’d been taught I I wanted to do much more than that I
wanted to do much more than that I
wanted to do much more than that I didn’t want surgery to be the last step
didn’t want surgery to be the last step
didn’t want surgery to be the last step I wanted to understand more and for this
I wanted to understand more and for this
I wanted to understand more and for this we have to turn to biology what can be
we have to turn to biology what can be
we have to turn to biology what can be done what can be done in science and
done what can be done in science and
done what can be done in science and scientific research and this is really
scientific research and this is really
scientific research and this is really what our main problem is for a lot of
what our main problem is for a lot of
what our main problem is for a lot of cancers that affect many different
cancers that affect many different
cancers that affect many different systems in the human body or
systems in the human body or
systems in the human body or problem isn’t necessarily with with the
problem isn’t necessarily with with the
problem isn’t necessarily with with the for the first the first forays into
for the first the first forays into
for the first the first forays into treatment still surgery is a very
treatment still surgery is a very
treatment still surgery is a very important part of treatment of cancer in
important part of treatment of cancer in
important part of treatment of cancer in many different systems so it seems like
many different systems so it seems like
many different systems so it seems like such a crude act to physically remove
such a crude act to physically remove
such a crude act to physically remove but still today it’s still one of the
but still today it’s still one of the
but still today it’s still one of the most important things that needs to be
most important things that needs to be
most important things that needs to be done in order to treat a person’s cancer
done in order to treat a person’s cancer
done in order to treat a person’s cancer but the problem is with recurrence so
but the problem is with recurrence so
but the problem is with recurrence so recurrence after first treatment is a
recurrence after first treatment is a
recurrence after first treatment is a main obstacle to cure for many cancers
main obstacle to cure for many cancers
main obstacle to cure for many cancers including and especially brain cancer so
including and especially brain cancer so
including and especially brain cancer so one of the cancers that were very
one of the cancers that were very
one of the cancers that were very interested in which is quite common in
interested in which is quite common in
interested in which is quite common in young young people is a tumor called
young young people is a tumor called
young young people is a tumor called medulloblastoma and so I turn to
medulloblastoma and so I turn to
medulloblastoma and so I turn to thinking about well first what what do
thinking about well first what what do
thinking about well first what what do these tumors look like under a
these tumors look like under a
these tumors look like under a microscope and so this is a typical
microscope and so this is a typical
microscope and so this is a typical picture of a medulla blastoma where here
picture of a medulla blastoma where here
picture of a medulla blastoma where here purple is staining the nuclei and pink
purple is staining the nuclei and pink
purple is staining the nuclei and pink stains the cytoplasm of the cells and so
stains the cytoplasm of the cells and so
stains the cytoplasm of the cells and so here there are many cells packed
here there are many cells packed
here there are many cells packed together and essentially all of this
together and essentially all of this
together and essentially all of this looks quite similar all the cells
looks quite similar all the cells
looks quite similar all the cells morphologically look similar so I asked
morphologically look similar so I asked
morphologically look similar so I asked a question is that really true are those
a question is that really true are those
a question is that really true are those cells really truly the same and so we
cells really truly the same and so we
cells really truly the same and so we started to ask that question by staining
started to ask that question by staining
started to ask that question by staining tumors for different markers and we had
tumors for different markers and we had
tumors for different markers and we had a clue that cancer of the brain might be
a clue that cancer of the brain might be
a clue that cancer of the brain might be like an aberrant developmental process
like an aberrant developmental process
like an aberrant developmental process based on stem cells and I’ll come back
based on stem cells and I’ll come back
based on stem cells and I’ll come back to that more detail but so what we
to that more detail but so what we
to that more detail but so what we wanted to do and this this this was from
wanted to do and this this this was from
wanted to do and this this this was from a model of the same cancer that that can
a model of the same cancer that that can
a model of the same cancer that that can be modeled in an animal and we stained
be modeled in an animal and we stained
be modeled in an animal and we stained cells within that tumor with different
cells within that tumor with different
cells within that tumor with different markers and so these these are markers
markers and so these these are markers
markers and so these these are markers sox2 dcx and new end they represent
sox2 dcx and new end they represent
sox2 dcx and new end they represent markers of stem cells progenitor cells
markers of stem cells progenitor cells
markers of stem cells progenitor cells and mature cells of the normal brain and
and mature cells of the normal brain and
and mature cells of the normal brain and so we find these normal markers also in
so we find these normal markers also in
so we find these normal markers also in the tumor and this suggests that maybe
the tumor and this suggests that maybe
the tumor and this suggests that maybe there’s a relationship between those
there’s a relationship between those
there’s a relationship between those cells maybe this type of cancer
cells maybe this type of cancer
cells maybe this type of cancer represents an abnormal stem cell system
represents an abnormal stem cell system
represents an abnormal stem cell system and key point here is that the stem
and key point here is that the stem
and key point here is that the stem cells which expresses gene
cells which expresses gene
cells which expresses gene sox2 are relatively few but we think
sox2 are relatively few but we think
sox2 are relatively few but we think those are the key cells so we faced with
those are the key cells so we faced with
those are the key cells so we faced with that initial information we want to ask
that initial information we want to ask
that initial information we want to ask this question our relationships between
this question our relationships between
this question our relationships between stem cells and they’re more mature
stem cells and they’re more mature
stem cells and they’re more mature daughter cell progeny maintained in a
daughter cell progeny maintained in a
daughter cell progeny maintained in a cancer context and I’m going to show you
cancer context and I’m going to show you
cancer context and I’m going to show you tell you show you a little bit of some
tell you show you a little bit of some
tell you show you a little bit of some experiments that suggest that the answer
experiments that suggest that the answer
experiments that suggest that the answer to that is yes there’s a lot of
to that is yes there’s a lot of
to that is yes there’s a lot of excitement now over the last 20 years
excitement now over the last 20 years
excitement now over the last 20 years that our brain is more dynamic than we
that our brain is more dynamic than we
that our brain is more dynamic than we ever thought before because there are
ever thought before because there are
ever thought before because there are several regions in the brain where there
several regions in the brain where there
several regions in the brain where there are new neurons made in the brain that
are new neurons made in the brain that
are new neurons made in the brain that that may play a role in for example in
that may play a role in for example in
that may play a role in for example in memory formation in a part of the brain
memory formation in a part of the brain
memory formation in a part of the brain called the hippocampus which is on the
called the hippocampus which is on the
called the hippocampus which is on the inner part of the temporal lobe and
inner part of the temporal lobe and
inner part of the temporal lobe and perhaps making new neurons is essential
perhaps making new neurons is essential
perhaps making new neurons is essential to being able to generate new memories
to being able to generate new memories
to being able to generate new memories but so the stem cells reside within they
but so the stem cells reside within they
but so the stem cells reside within they generate other cells that amplify the
generate other cells that amplify the
generate other cells that amplify the number of cells because they divide
number of cells because they divide
number of cells because they divide frequently and ultimately they undergo a
frequently and ultimately they undergo a
frequently and ultimately they undergo a process called differentiation or
process called differentiation or
process called differentiation or maturation into cells that are neurons
maturation into cells that are neurons
maturation into cells that are neurons or glia which are astrocytes are oolagah
or glia which are astrocytes are oolagah
or glia which are astrocytes are oolagah dentro sites supporting cells for the
dentro sites supporting cells for the
dentro sites supporting cells for the neurons and so in the normal context
neurons and so in the normal context
neurons and so in the normal context during development that process works as
during development that process works as
during development that process works as a baby’s brain grows during development
a baby’s brain grows during development
a baby’s brain grows during development and there’s there’s more robust activity
and there’s there’s more robust activity
and there’s there’s more robust activity of that early on in life in humans and
of that early on in life in humans and
of that early on in life in humans and there’s that diminishes over time but in
there’s that diminishes over time but in
there’s that diminishes over time but in the normal context to make that
the normal context to make that
the normal context to make that beautiful brain that you saw those
beautiful brain that you saw those
beautiful brain that you saw those pictures of that these processes are
pictures of that these processes are
pictures of that these processes are extremely tightly regulated and are
extremely tightly regulated and are
extremely tightly regulated and are beautifully orchestrated and I like this
beautifully orchestrated and I like this
beautifully orchestrated and I like this image from one of my favorite records
image from one of my favorite records
image from one of my favorite records that that that illustrates the this
that that that illustrates the this
that that that illustrates the this process but in cancer we think all those
process but in cancer we think all those
process but in cancer we think all those there’s a resemblance to that those kind
there’s a resemblance to that those kind
there’s a resemblance to that those kind of relationships it’s now gone haywire
of relationships it’s now gone haywire
of relationships it’s now gone haywire but there are some clues within that
but there are some clues within that
but there are some clues within that tell us what we can do so another key
tell us what we can do so another key
tell us what we can do so another key point is cancers often represent
point is cancers often represent
point is cancers often represent distortions of our normal selves and to
distortions of our normal selves and to
distortions of our normal selves and to take that one step further in the brain
take that one step further in the brain
take that one step further in the brain is brain cancers represent a bear
is brain cancers represent a bear
is brain cancers represent a bear and developmental processes and brain
and developmental processes and brain
and developmental processes and brain cancers we think grow because they
cancers we think grow because they
cancers we think grow because they contain genetically abnormal stem cells
contain genetically abnormal stem cells
contain genetically abnormal stem cells that are our if you will on a misguided
that are our if you will on a misguided
that are our if you will on a misguided mission to grow abnormal brain tissue
mission to grow abnormal brain tissue
mission to grow abnormal brain tissue and so we need to understand that
and so we need to understand that
and so we need to understand that process and so I’m just going to show
process and so I’m just going to show
process and so I’m just going to show you one example of one experiment that
you one example of one experiment that
you one example of one experiment that supports this idea and it’s it’s a
supports this idea and it’s it’s a
supports this idea and it’s it’s a classical experiment that that
classical experiment that that
classical experiment that that scientists who are interested in
scientists who are interested in
scientists who are interested in development of tissues does it’s
development of tissues does it’s
development of tissues does it’s something called a lineage trace and
something called a lineage trace and
something called a lineage trace and it’s a definitive measurement of the
it’s a definitive measurement of the
it’s a definitive measurement of the potency of a cell that’s marked in a
potency of a cell that’s marked in a
potency of a cell that’s marked in a tissue and it tells us whether how well
tissue and it tells us whether how well
tissue and it tells us whether how well that tissue can replenish and how how
that tissue can replenish and how how
that tissue can replenish and how how that tissue matures and we wanted to ask
that tissue matures and we wanted to ask
that tissue matures and we wanted to ask this question
this question
this question those five percents those few little
those five percents those few little
those five percents those few little green cells I showed you in that picture
green cells I showed you in that picture
green cells I showed you in that picture that expressed this gene key gene called
that expressed this gene key gene called
that expressed this gene key gene called sox2 could those cells be at the roots
sox2 could those cells be at the roots
sox2 could those cells be at the roots of growth of this type of childhood
of growth of this type of childhood
of growth of this type of childhood tumor and so a graduate student in my
tumor and so a graduate student in my
tumor and so a graduate student in my lab robert van ER did the experiment it
lab robert van ER did the experiment it
lab robert van ER did the experiment it was a very difficult experiment but what
was a very difficult experiment but what
was a very difficult experiment but what he was able to do is he could we used a
he was able to do is he could we used a
he was able to do is he could we used a genetic trick that was embedded into
genetic trick that was embedded into
genetic trick that was embedded into animals that would that would grow up
animals that would that would grow up
animals that would that would grow up medulloblastoma naturally and this model
medulloblastoma naturally and this model
medulloblastoma naturally and this model is very close to the to the sharing the
is very close to the to the sharing the
is very close to the to the sharing the same genetic changes in the same the
same genetic changes in the same the
same genetic changes in the same the tumors look the same as the human tumors
tumors look the same as the human tumors
tumors look the same as the human tumors they express the same abnormal genetic
they express the same abnormal genetic
they express the same abnormal genetic programs as a human tumor so we thought
programs as a human tumor so we thought
programs as a human tumor so we thought it was it was a terrific model and here
it was it was a terrific model and here
it was it was a terrific model and here was something that you actually can’t do
was something that you actually can’t do
was something that you actually can’t do in a human being but you can do in a
in a human being but you can do in a
in a human being but you can do in a very good animal model so what Robert
very good animal model so what Robert
very good animal model so what Robert was able to do is he could mark the Sox
was able to do is he could mark the Sox
was able to do is he could mark the Sox to positive cells and show initially
to positive cells and show initially
to positive cells and show initially that these were few cells in the tumor
that these were few cells in the tumor
that these were few cells in the tumor and then what we did is we followed that
and then what we did is we followed that
and then what we did is we followed that tumor over time to trace the progeny of
tumor over time to trace the progeny of
tumor over time to trace the progeny of these mark cells and essentially what
these mark cells and essentially what
these mark cells and essentially what happens here is that cell becomes
happens here is that cell becomes
happens here is that cell becomes acquires a color core this red color
acquires a color core this red color
acquires a color core this red color when that cell divided and generated two
when that cell divided and generated two
when that cell divided and generated two daughter cells both the daughter cells
daughter cells both the daughter cells
daughter cells both the daughter cells became red and then as they divided both
became red and then as they divided both
became red and then as they divided both their daughter cells become red and over
their daughter cells become red and over
their daughter cells become red and over time we wanted to watch to see if the
time we wanted to watch to see if the
time we wanted to watch to see if the tumor turn
tumor turn
tumor turn red and essentially and here’s the real
red and essentially and here’s the real
red and essentially and here’s the real experiment it shows that the tumor grows
experiment it shows that the tumor grows
experiment it shows that the tumor grows based on the division and multiplication
based on the division and multiplication
based on the division and multiplication of a rare population of cells that
of a rare population of cells that
of a rare population of cells that reside within strongly supporting that
reside within strongly supporting that
reside within strongly supporting that this this type of tumor is driven in a
this this type of tumor is driven in a
this this type of tumor is driven in a based on an aberrant stem cell system so
based on an aberrant stem cell system so
based on an aberrant stem cell system so on the right you can see over several
on the right you can see over several
on the right you can see over several weeks the tumor essentially turns red
weeks the tumor essentially turns red
weeks the tumor essentially turns red and it came from few cells so these
and it came from few cells so these
and it came from few cells so these cells we think are at the root of the
cells we think are at the root of the
cells we think are at the root of the growth of this kind of cancer and the
growth of this kind of cancer and the
growth of this kind of cancer and the key thing here is we then started to
key thing here is we then started to
key thing here is we then started to test conventional treatments in in in
test conventional treatments in in in
test conventional treatments in in in this model to see how do the
this model to see how do the
this model to see how do the conventional treatments target these
conventional treatments target these
conventional treatments target these different cell types in these in these
different cell types in these in these
different cell types in these in these tumors and essentially what we found
tumors and essentially what we found
tumors and essentially what we found here is that the usual treatments were
here is that the usual treatments were
here is that the usual treatments were were fantastic at killing a lot of the
were fantastic at killing a lot of the
were fantastic at killing a lot of the cells in the tumor we found good drugs
cells in the tumor we found good drugs
cells in the tumor we found good drugs already that also work in patients that
already that also work in patients that
already that also work in patients that are very good at at shrinking these
are very good at at shrinking these
are very good at at shrinking these tumors and and improving the symptoms
tumors and and improving the symptoms
tumors and and improving the symptoms but but what you may not be able to see
but but what you may not be able to see
but but what you may not be able to see so well here but on the right is after
so well here but on the right is after
so well here but on the right is after the treatment we see more red cells in
the treatment we see more red cells in
the treatment we see more red cells in this tumor and what that means is that
this tumor and what that means is that
this tumor and what that means is that the we spared a population of cells
the we spared a population of cells
the we spared a population of cells we’re leaving something behind we’re
we’re leaving something behind we’re
we’re leaving something behind we’re leaving a reservoir of cells behind that
leaving a reservoir of cells behind that
leaving a reservoir of cells behind that may show the capacity to regrow the
may show the capacity to regrow the
may show the capacity to regrow the tumor and and so in applying the stem
tumor and and so in applying the stem
tumor and and so in applying the stem cell biology approach this developmental
cell biology approach this developmental
cell biology approach this developmental framework if you will to thinking about
framework if you will to thinking about
framework if you will to thinking about how cancer grows we can start to divide
how cancer grows we can start to divide
how cancer grows we can start to divide up different cell types in the tumor in
up different cell types in the tumor in
up different cell types in the tumor in two distinct compartments I’m not going
two distinct compartments I’m not going
two distinct compartments I’m not going to go over all of this but essentially
to go over all of this but essentially
to go over all of this but essentially there are a few cells that are that have
there are a few cells that are that have
there are a few cells that are that have a stem cell property that actually
a stem cell property that actually
a stem cell property that actually another key point about those cells is
another key point about those cells is
another key point about those cells is that they’re very slowly dividing they
that they’re very slowly dividing they
that they’re very slowly dividing they and our general treatments for cancer
and our general treatments for cancer
and our general treatments for cancer are very good at targeting cells that
are very good at targeting cells that
are very good at targeting cells that are rapidly dividing we figure that
are rapidly dividing we figure that
are rapidly dividing we figure that process out but we haven’t figured out
process out but we haven’t figured out
process out but we haven’t figured out so well how to deal with cells that are
so well how to deal with cells that are
so well how to deal with cells that are lurking within the cancer that maybe
lurking within the cancer that maybe
lurking within the cancer that maybe have a very slow dividing
have a very slow dividing
have a very slow dividing potential seems like the drugs that we
potential seems like the drugs that we
potential seems like the drugs that we have don’t target these slowly cycling
have don’t target these slowly cycling
have don’t target these slowly cycling cells those cells in turn generates
cells those cells in turn generates
cells those cells in turn generates progeny that divide fast which are
progeny that divide fast which are
progeny that divide fast which are cancer progenitors which respond to
cancer progenitors which respond to
cancer progenitors which respond to chemotherapy which we can wipe out and
chemotherapy which we can wipe out and
chemotherapy which we can wipe out and eventually those cells undergo a
eventually those cells undergo a
eventually those cells undergo a maturation process not like the normal
maturation process not like the normal
maturation process not like the normal brain but still resembling the normal
brain but still resembling the normal
brain but still resembling the normal brain but these cells that mature
brain but these cells that mature
brain but these cells that mature actually are short live and are
actually are short live and are
actually are short live and are eliminated and although they form a
eliminated and although they form a
eliminated and although they form a component of the mass of the tumor which
component of the mass of the tumor which
component of the mass of the tumor which can cause symptoms they actually
can cause symptoms they actually
can cause symptoms they actually disappear over time they’re programmed
disappear over time they’re programmed
disappear over time they’re programmed to disappear and it may be analogous to
to disappear and it may be analogous to
to disappear and it may be analogous to what also happens in the developing
what also happens in the developing
what also happens in the developing brain we during development we generate
brain we during development we generate
brain we during development we generate way way more neurons than we need and as
way way more neurons than we need and as
way way more neurons than we need and as those neurons start to make connections
those neurons start to make connections
those neurons start to make connections a lot of the extra neurons are pruned so
a lot of the extra neurons are pruned so
a lot of the extra neurons are pruned so we there may be this process is also
we there may be this process is also
we there may be this process is also being recapitulated in this cancer
being recapitulated in this cancer
being recapitulated in this cancer context but what this tells us also is
context but what this tells us also is
context but what this tells us also is that we need different types of
that we need different types of
that we need different types of treatments for these different types of
treatments for these different types of
treatments for these different types of cells and applying the stem cell
cells and applying the stem cell
cells and applying the stem cell thinking means we don’t we not we not
thinking means we don’t we not we not
thinking means we don’t we not we not only have to target the fast awaiting
only have to target the fast awaiting
only have to target the fast awaiting cells we need something that targets the
cells we need something that targets the
cells we need something that targets the slow dividing cells or maybe what we
slow dividing cells or maybe what we
slow dividing cells or maybe what we should do is just force all of these
should do is just force all of these
should do is just force all of these cells to mature into these
cells to mature into these
cells to mature into these differentiated cell types and then those
differentiated cell types and then those
differentiated cell types and then those cells what cells will have a limited
cells what cells will have a limited
cells what cells will have a limited lifespan and will disappear so I think
lifespan and will disappear so I think
lifespan and will disappear so I think one of the key points I want to get
one of the key points I want to get
one of the key points I want to get across today and I think it applies
across today and I think it applies
across today and I think it applies generally to cancer is not every cancer
generally to cancer is not every cancer
generally to cancer is not every cancer is functionally created equal even if
is functionally created equal even if
is functionally created equal even if they may have the same genetic changes
they may have the same genetic changes
they may have the same genetic changes they’re not behaving the same way and we
they’re not behaving the same way and we
they’re not behaving the same way and we need to figure that out so cancer is
need to figure that out so cancer is
need to figure that out so cancer is much more than genetic mutations genetic
much more than genetic mutations genetic
much more than genetic mutations genetic mutations are essential to get cancer
mutations are essential to get cancer
mutations are essential to get cancer growing are essential to be cancer but
growing are essential to be cancer but
growing are essential to be cancer but but it’s how those genetic changes are
but it’s how those genetic changes are
but it’s how those genetic changes are being used by the cells that also
being used by the cells that also
being used by the cells that also dictates the way that cancer behaves so
dictates the way that cancer behaves so
dictates the way that cancer behaves so we think that cancer reflects how
we think that cancer reflects how
we think that cancer reflects how genetic changes shape the behavior of
genetic changes shape the behavior of
genetic changes shape the behavior of normal tissue growth and regenerative
normal tissue growth and regenerative
normal tissue growth and regenerative processes and in our in our group we’ve
processes and in our in our group we’ve
processes and in our in our group we’ve identified a cellular target in
identified a cellular target in
identified a cellular target in medulloblastoma
medulloblastoma
medulloblastoma and also in glioblastoma of adults and
and also in glioblastoma of adults and
and also in glioblastoma of adults and we’re starting to characterize more of
we’re starting to characterize more of
we’re starting to characterize more of the programs that dictate the behavior
the programs that dictate the behavior
the programs that dictate the behavior of those cells and we think that we have
of those cells and we think that we have
of those cells and we think that we have the cell in hand that is responsible for
the cell in hand that is responsible for
the cell in hand that is responsible for the root growth of these tumors but also
the root growth of these tumors but also
the root growth of these tumors but also responsible for the recurrence having
responsible for the recurrence having
responsible for the recurrence having these cells at hand
these cells at hand
these cells at hand gives us the chance to discover new
gives us the chance to discover new
gives us the chance to discover new therapies that may more that may better
therapies that may more that may better
therapies that may more that may better affect long lasting cures so I think
affect long lasting cures so I think
affect long lasting cures so I think there is hope for a better future for
there is hope for a better future for
there is hope for a better future for for children and adults with brain
for children and adults with brain
for children and adults with brain cancer based on applying this kind of
cancer based on applying this kind of
cancer based on applying this kind of framework to understanding brain cancer
framework to understanding brain cancer
framework to understanding brain cancer and it and really as someone who started
and it and really as someone who started
and it and really as someone who started off as a clinician as a surgeon I love
off as a clinician as a surgeon I love
off as a clinician as a surgeon I love what I do in looking after a patient’s
what I do in looking after a patient’s
what I do in looking after a patient’s and being able to use my hands and to be
and being able to use my hands and to be
and being able to use my hands and to be able to have a dramatic impact on
able to have a dramatic impact on
able to have a dramatic impact on someone’s life
someone’s life
someone’s life with an operation but I recognize that
with an operation but I recognize that
with an operation but I recognize that still there’s limitations in what we can
still there’s limitations in what we can
still there’s limitations in what we can do with our hands and I think we’re not
do with our hands and I think we’re not
do with our hands and I think we’re not we’re not yet to be replaced by robots
we’re not yet to be replaced by robots
we’re not yet to be replaced by robots because still there’s aspects of the
because still there’s aspects of the
because still there’s aspects of the human motor and sensory systems that
human motor and sensory systems that
human motor and sensory systems that still can’t be replaced by robots so we
still can’t be replaced by robots so we
still can’t be replaced by robots so we need surgeons but we need much more than
need surgeons but we need much more than
need surgeons but we need much more than surgery we need to understand biology
surgery we need to understand biology
surgery we need to understand biology and I think the key for for young people
and I think the key for for young people
and I think the key for for young people is science Canada and the world needs
is science Canada and the world needs
is science Canada and the world needs more people engaged in scientific
more people engaged in scientific
more people engaged in scientific research to ask creative original
research to ask creative original
research to ask creative original questions and to think outside the box
questions and to think outside the box
questions and to think outside the box we think in a way we thought outside of
we think in a way we thought outside of
we think in a way we thought outside of the box and look and looking at brain
the box and look and looking at brain
the box and look and looking at brain cancer this way and we’re very hopeful
cancer this way and we’re very hopeful
cancer this way and we’re very hopeful what that might mean for the future
what that might mean for the future
what that might mean for the future thank you very much for your attention
thank you very much for your attention
thank you very much for your attention [Applause]
”
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