good afternoon
the revolution is called
and it's based on the process that our bodies use to grow blood vessels
so why should we care about blood vessels
the smallest blood vessels are called capillaries we've got nineteen billion of them in our bodies and these are the vessels of life
and as i'll show you they can also be the vessels of death
now the remarkable thing about blood vessels is that they have this ability to adapt to whateverenvironment they're growing in for example in the liver they form channels to detoxify the blood
in the lung they line air sacs for gas exchange in muscle they corkscrew so that muscles can contract without cutting off circulation and in nerves they course along like power lines keeping those nerves alive
and we get most of these blood vessels when we're actually still in the womb
except in a few special circumstances
in women blood vessels grow every month to build the lining of the uterus during pregnancy they form the placenta which connects
mom and baby and after injury blood vessels actually have to grow under the scab in order to heal
by releasing stimulators proteins called angiogenic factors that act as natural fertilizer and stimulate new blood vessels to sprout
now there are other situations where we start beneath the baseline and we need to grow more blood vessels just to get back to normal levels for example after an injury and a body can do that too
but only to that normal level that set point but what we now know is
a number of diseases there are defects in the system
out of balance a myriad of diseases result for example insufficient angiogenesis not enough blood vessels leads to wounds that don't heal heart attacks legs without circulation death from stroke nerve damage
in total there are more than seventy major diseases effecting more than a billion people worldwide that all look on the surface to be
focus on cancer because angiogenesis is a hallmark of cancer
every type of cancer so here we go
this is a tumor dark gray ominous mass growing inside a brain and under the microscope you can see hundreds of these brown staining blood vessels capillaries that are feeding cancer cells bringing oxygen and nutrients
but cancers don't start out like this and in fact cancers don't start out with a blood supply they start out as small microscopic nests of cells
can only grow to one half a cubic millimeter in size that's the tip of a ballpoint pen
then they can't get any larger because they don't have a blood supply so they don't have enough oxygen or nutrients and in fact we're probably forming these microscopic cancers all the time in our body
autopsy studies from people who died in car accidents have shown that about forty percent of women between the ages of forty and fifty
actually have microscopic cancers in their breasts
and virtually one hundred percent of us by the time we reach our seventies will have microscopic cancers growing in our thyroid
yet without a blood supply most of these cancers will never become dangerous
doctor judah folkman who was my mentor and who was the pioneer of the angiogenesis field once called this cancer without disease
so the body 's ability to balance angiogenesis when it's workingproperly prevents blood vessels from feeding cancers and this turns out to be one of our most important defense mechanisms against cancer
in fact if you actually block angiogenesis and prevent blood vessels from ever reaching cancer cells tumors simply can't grow up
but once angiogenesis occurs cancers can grow exponentially and this is actually how a cancer goes from being harmless to deadly
as metastases and unfortunately this late stage of cancer is the one at which it's most likely to be diagnosed
when angiogenesis is already turned on and cancer cells are growing like
is a tipping point
one major part of the angiogenesis revolution
is a new approach to treating cancer by cutting off the blood supply
we call this antiangiogenic therapy
and we can do this because tumor blood vessels are unlikenormalhealthy vessels we see in other places of the body they're abnormal they're very poorly constructed and because of that they're highly vulnerable to treatments that target
in effect when we give cancer patients antiangiogenic therapy here
an experimental drug for a glioma which is a type of
tumor you can see that there are dramatic changes that occur when the tumor is being starved
here 's a woman with a breast cancer being treated with the antiangiogenic drug called avastin which is fda approved and you can see that the halo of blood flow disappears after treatment
just shown you two very different types of cancer
both responded to antiangiogenic therapy
so a few years ago i asked myself can we take this one step further and treat other cancers even in other species
slow down that cancer 's growth such that we were ultimately able to extend milo 's survival to six times what the veterinarian had initially predicted
all with a very good quality of life
and we subsequently treated more than six hundred dogs we have about a sixty percent response rate and improved survival for these pets that were about to be euthanized
so let me show you a couple of even more interesting examples
this is twenty year old dolphin living in florida and she had these lesions in her mouth that over the course of three years developed into
so we created an antiangiogenic paste we had it painted on top of the cancer three times a week and over the course of seven months the cancers completely disappeared and the biopsies came back as normal
here 's a cancer growing on the lip
a quarter horse named guiness
the outside and over the course of six months
a complete remission
and here he is six years later
guiness with his very happy
there's twelve different drugs eleven different cancer types but the real question is how well do these work in practice so here 's actually the
from eight different types of cancer and the bars represent survival time taken from the era in which there was only chemotherapy or surgery or radiation available
but starting in two thousand and four
when antiangiogenic therapies first became available well you can see that there has been a seventy to one hundred percent improvement in survival for people with kidneycancer multiple myeloma
so i started asking myself why haven't we been able to do better
and the answer to me is obvious we're treating cancer too late in the game when it's already established and oftentimes it's already spread or metastasized
and as a doctor i know that once a disease progresses to an advanced stage achieving a cure can be difficult if not impossible
so i went back to the biology of angiogenesis and started thinking
could the answer to cancer be preventing angiogenesis
beating cancer at its own game so the cancers could never become dangerous
this could help healthy people as well as people who 've already beatencancer once or twice and want to find a way to keep it from coming back
i saw that diet accounts for thirty to thirty five percent of environmentally caused cancers
now the obvious thing is to think about what we could remove from our diet what what to strip out take away
but i actually took a completely opposite approach and began asking what could we be adding to our diet that's naturally antiangiogenic
could boost the body 's defense system and beat back those blood vessels that are feeding cancers in other words can we eat to starve cancer
well the answer 's yes and i'm going to show you how
our search for this has taken us to the market the farm and to the spice cabinet because what we've discovered is that mother nature has laced a large number of foods and beverages and herbs with naturally occurring inhibitors of
so let me show you what happens when we put in an extract from red grapes the
it's also found in red wine
this inhibits abnormal angiogenesis by sixty percent
it potently inhibits angiogenesis
and here is a growing list of our antiangiogenic foods and beverages that we're interested in studying and for each food type
we believe there is different potencies within different strains and varietals and we want to measure this because well while you're eating a strawberry or drinking tea why not select the one that's most potent for preventing cancer
so here are
chinese jasmine japanese sencha earl grey and a special blend that we prepared
and you can see clearly that the teas vary in
potency from less potent to more potent
but what's very cool is when we actually combined the two less potent teas together
the combination the blend is more potent than either one
this means there's food
tumor angiogenesis represented here in a black bar and using this system we can test the potency of cancer drugs so the shorter the bar less angiogenesis that's good
and here are some common drugs that have been associated with reducing the risk of cancer in people statins nonsteroidal anti inflammatory drugs and a few others
they inhibit angiogenesis too
and here are the dietary factors going head to head against these drugs
so imagine if we could create the world 's first rating system in which we could score foods according to their antiangiogenic cancer preventative properties and that's what we're doing right now
now i've shown you a bunch of lab data and so the real question is what is the evidence in people that eating certain foods can reduce angiogenesis in cancer
well the best example i know is a study of seventy nine thousand men followed over twenty years
in which it was found that men whom consumed cooked tomatoes two to three times a week had up to a fifty percent reduction in their risk of developing prostate cancer
now we know that tomatoes are a good source of lycopene and lycopene is antiangiogenic
so this human study is a prime example of how antiangiogenic substances present in food and consumed at practical levels can impact on cancer
and we're now studying the role of a healthy diet with dean ornish and ucsf and tufts university on the role of this healthy diet on markers of angiogenesis that we can find in the bloodstream
now obviously what i've shared with you has some far ranging implications even beyond cancerresearch because if we're right it could impact on consumer education
food services public health and even the insurance industry and in fact some insurance companies are already beginning to think along these lines check out this ad from blue cross blue shield of minnesota
but everybody could benefit from a healthy diet based on local sustainable antiangiogenic crops
finally i've talked to you about food and i've talked to you about cancer so there's just one more disease that i have to tell you about and that's obesity
turns out that adipose tissue fat is highly angiogenesis dependent and like a tumor fat grows when blood vessels grow so the question is can we shrink fat be cutting off its blood supply
so the top curve shows the body weight of a genetically obese mouse that eats nonstop until it turns fat like this furry tennis ball
in fact you can cycle the weight up and down simply by inhibiting angiogenesis so this approach that we're taking for cancerprevention may also have an application for obesity
this is that we can't take these obese mice and make them lose more weight than what the normal mouse 's weight is supposed to be in other words we can't create supermodel mice
once said that discovery consists of seeing what everyone has seen and
i hope i've convinced you that for diseases like cancer obesity and other conditions that there may be a great power in attacking their common denominator angiogenesis and that's what i think the world needs now thank
more
consider the approved ones look for clinical trials
but then between what the doctor can do for you we need to start asking what can we do for ourselves and this is one of the themes that i'm talking about is we can empower ourselves to do the things that doctors can't do for us which is to use knowledge and take action
and if mother nature has given us some clues we think that there might be a new future in the value of what we eat and what we eat is really our chemotherapy three
right and along those lines for people who might have risk factors for cancer would you recommend pursuing any treatments sort of prophylactically or simple pursuing the right diet with lots of tomato sauce
to look for epidemiological studies for cancer risk reduction based on diet and based on common medications and that's certainly something that anybody can
okay well thank you so much
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