>> From the Library of Congress in Washington, D.C. >> Sandra Charles: Okay. Good morning, everyone. And welcome to this Joint Health Forum with Science and Technology Division of the Office of Health Services. I'm very pleased with this collaboration with Tomoko. And this is the second of two that we've done recently. And thank you all for coming. Today in honor not only but particularly because this is October and breast cancer awareness month, we're having an esteemed speaker who will be introduced by Tomoko -- Dr. Tomoko Steen. And we're waiting with baited breath to hear all the new developments from you, Dr. Clark. But it is -- it is a subject that we certainly address on an annual basis because it is still the number two cancer killer in women -- and probably the number one skin cancer -- that exists. So I just wanted to welcome you and to thank you for coming and hope that you will get as much out of it as we hope you will and that we expect you will. And without further ado, I'm going to ask Tomoko to come to the podium to introduce Dr. Clark. Thank you very much. >> Tomoko Steen: It's my great pleasure to introduce today's speaker, Dr. Clark. And he's a senior colleague of mine. Today's talk is actually part of the translational medicine series. We started with two Nobel laureates. Jim Watson and Carol Greider came. In fact, Professor Clark was one of the speaker was supposed to be, but the schedule didn't work out. And I'm so glad to be able to invite him back for this topic. Professor Clark is dean for research at the Georgetown University Medical School and also Professor of Oncology and Core Director of the Breast Cancer Program at Lombardi Comprehensive Cancer Center. And he has done the DSc and PhD at Belfast, actually, University of Queens. And also, he has done the post-doctorate research at National Cancer Institute. And I have bio in the back. You can pick it up. And we have books on the -- basic books -- on breast cancer back there. So if you have time, please take a look. And before I go into the further ado, I should just introduce Professor Clark. Thank you so much. [ Applause ] >> Robert Clarke: Well, thank you. This is a great pleasure to be here. This is maybe going to be a little different today because I'm going to tell you about some of the research that's going on and how we've begun to think differently about understanding several different cancers but with a specific focus on breast cancer. Okay. Hands up if you know anyone -- yourself, anyone in your family or extended family -- who's ever had a diagnosis of breast cancer. Look around. Sadly, one in eight women -- I'll show you the statistics in a minute -- are likely to experience a diagnosis of breast cancer in their lifetime. We made significant strides in managing this disease, and we do cure breast cancers; we just don't cure all breast cancers. We will get there. We probably won't get there as quickly as everyone would like, but we will get there. Today I'm going to give you an -- some insight into what the statistics are for breast cancer, who it affects, some of the drugs. I'm going to focus mostly on estrogen-receptor-positive breast cancer, which is about 70 percent of all breast cancers. And tell you how we've begun to take a different approach to understanding the biology of that disease and how that might lead us to think very differently about how we might treat that disease and ideally, eventually prevent it. Now, I've got a little bit of science in my slides. And probably none of you are breast cancer researchers. So please, if you don't understand anything, just stop me. I'm happy to take time and try and explains things to you as we go along. And if you see something that you don't understand, just make sure that we don't panic. Really, this is here to have as much conversation with you as I am to tell you what we do. I'd like you to learn something about breast cancer from today and go away with it and think about it. Because we all have a responsibility to do something in whatever way we can to eradicate this terrible disease. So don't panic if you see data, or crazy words, or symbols that sound like they're a foreign language. They probably are a foreign language; they're science language. But most of those you don't actually need to follow; just follow the idea. Don't worry about the details because it's the sort of big picture I'd like to get across to you today. So let's start by telling you something about cancer, just in case you don't know much. You might think that it's a disease of modern man in some way, shape, or form. But actually, it is one of those unfortunate side effects of just being alive. We've known cancer has been around for a very long time. And the dinosaurs got cancer. You might wonder how do we know that? Well, some cancers come up in bone. And so when fossils are created and the bones are left behind, you can actually see evidence that there was a cancer in the bone, in that fossil. And it turns out this is an example of one, apparently, who knew -- Hadrosaurus were particularly cancer-prone. Dinosaurs -- plants can get types of cancer. So it's really a very common disease. And I'm going to explain to you what cancer is. And then we're going to go and look at what breast cancer is. And I'm going to tell you something about some of the drugs that we have and how they work. And then we'll talk about how breast cancer cells get [inaudible]. And that's the key. We need to understand how to stop cancer cells escaping from when we're trying to kill them. So most cancers -- all cancers, really -- start with the DNA mutation, a change in the sequence of DNA that encodes for eventually the proteins that allow our cells to perform functions. And sometimes when those changes occur, it screws up the ability of the cells to function properly, and in some cases it leads to cancer. So it starts with a mutation. That doesn't mean that we know what that mutational event is in all cancers -- we clearly don't. In some cases breast cancer would be an example. We know that some are caused by a mutation in a particular gene, like the BRCA1 gene or the BRCA2 gene, which you've probably heard of. Those are mutations that lead to more mutations that build up in the cell. And eventually we get cancer. And -- and to all intents and purposes, cancer is really a disease where there's loss of the normal controls on proliferation and growth. It's where cells start to make copies of themselves when they shouldn't and in places where they don't belong is probably the easiest way to think of it. There's a wonderful set of slides which I have borrowed from that the National Cancer Institute has made that you can download and look at in your own time if you want to see -- learn a little bit more just about the basics. But this is -- and this is one of them, for example. So you can see at the top you've got these cells that go through normal division because as cells get old or die, they need to be replaced. Or if they get damaged, they need to be replaced. So that's a natural process. It's when that goes wrong, the control of that goes wrong and you start to get growth of cells where they don't belong and it's no longer controlled. We usually call that a tumor. And they come in different types. They can grow in one place and never go anywhere else. They can grow in one place and stop and do very little harm. But the ones that are the biggest problem and for which breast cancer is an example are the ones that find -- that don't stop. They don't stop in the breast, they don't stop in that little place where they started and they start to spread into the tissues around. And eventually they get into the lymphatic system or they get into the blood system and they go all over the body. And some of them will stick in other parts of the body and start to grow, and then you have what's called metastasis. And you get spread of the disease all over the body. That's usually the process that kills most women and the small number of men who get breast cancer -- that process of metastatic advanced disease. So this is what the breast looks like when you're thinking conceptually. The breast, of course, is there for one purpose only: To make milk. And we wouldn't be here as a species if it wasn't for the milk that's produced in the breast. And it's made in these little -- in these glandular structures here. And then it gets expelled into these ducts and comes out through the nipple. That's the natural process that occurs during what we call lactation, after pregnancy when a woman has given birth and she's making milk in her breast. Sometimes things go wrong in the cells that line these ducts and you end up with a tumor. And you can see here this is an example of a tumor that began here in this quadrant of the breast. Sometimes it will get out of the breast and end up in the lymph nodes. So there are lymph nodes that are in the breast -- that's often call the sentinel lymph node. And there are the ones turned the arm in the axilla. And so often when there's an initial diagnosis of breast cancer, the doctor will want to know is it in the lymph nodes, either in the breast or under the arm? And that tells us a lot about -- just knowing whether it's there or not tells us a lot about the potential of that cancer to be in other places. So often if it's confined to the breast, if we can have the surgeon remove it and the radiotherapist come along and use radiation to burn away and kill any few cells that the surgeon might have missed, that woman can go away and she's completely cured. But many women, as you know, that cancer has already got to the lymph nodes, or to the lungs, or the brain, or the skin, or the bone, or the liver. And then it's a much more difficult disease to manage. That's the sort of natural history of breast cancer from sort of soup to nuts, if you like. So let's look at the incidence and what we think we know about what might cause breast cancer. So in this top panel here where it says -- that circle there where there's known risk factors, most women who get a diagnosis of breast cancer have none of these risk factors. We really still don't know what causes most breast cancers. We know a number of things that can increase the risk on a population basis. If we look at those women, we can say that if some of these women have been exposed to one, two, or threes of these things, their risk is higher. But that doesn't mean that we can go in and say "And you're the one that has a risk that's twice as high as anybody else's as an individual and you're the one that's going to cancer." We can't do that. We can only look at large numbers of women and draw broad conclusions or associations about what is this correlated with breast cancer? The panel below, the circle, shows you the age distribution of breast cancer. It doesn't arise in children before puberty. It's extremely rare in very young women. The incidence increases with age. And the highest increase, as you can see from that middle chart is just around the age when women go through menopause. So it is a disease of getting older primarily but not obviously exclusively. In terms of why is that the case, the longer you live, the more cells you have in your body that go through and are replaced. And every time you replace a cell, there's a risk that the DNA, when it's replicated, makes a mistake and you get a mutation by chance increases. So it simply increases with age. That's one explanation, probably the simplest way to think of it. It's obviously a little more complicated. But that's enough for now to get the basic idea. If you inherit a BRCA1 or BRCA2 mutation -- and that's shown in the table at the top -- the risk of getting breast cancer is very high. But the percentage of women who inherit mutated BRCA1 is fortunately relatively low. So it doesn't explain most breast cancers, it explains some. And we can find out from looking at family histories who's likely to be in a family that might have a BRCA1 or BRCA2 mutation, and we can identify those women if someone in their family, for example, comes in with a breast cancer and we take their history. And we can sequence from just a buccal swab, for example. We can sequence that BRCA1 gene and determine whether they're in one of these breast cancer families. And that allows that family to make decisions as to who else wishes to get screened and what they might want to do with that information. We have a whole set of folks called genetic counselors who will help people work through that issue if they find that they're a carrier of this. One in eight women is a lot; men, too. But not so many largely because the amount of breast tissue in men is -- is much smaller than it is in women. There's a small residual piece of breast epithelial tissue where the cancers arise present in men also. But it's so small that -- and there are so few cell there are relative to women, that probably explains why the risk is much lower to men. On the panel that shows the young woman, breast cancer is caused by the interaction of genes in the environment. It's wonderful to say that. So what genes and what in the environment? That's a mess -- that's much harder to figure out because we have tens of thousands of genes, and they make proteins in different forms. We don't always know what they all do. And then there are so many things in the environment. And if it's a combination of things and not a single exposure in the environment, it's very, very, very difficult to figure out what it is that's actually causing that. So for most people, we really have no idea if they didn't inherit a BRCA1 or BRCA2. We only know a few things that might elevate their risk slightly, and almost none of those are anything you can do anything about. So if someone says, "I just got a diagnosis. Why me, what did I do wrong?" You probably didn't do anything wrong. Almost certainly you did nothing. There is very little that you can do to fundamentally change your lifetime risk. There are things that you can do that are -- that can moderate that to some degree: Exercise, a healthy diet -- the things that everybody keeps telling you to do for a whole series of different diseases can help to keep your risk of breast cancer down. But fundamentally, what is it that's driving it is still something we still have a long way to go to understand. And these are the numbers. Now, they are kind of scary. 230,000 new cases every year. 230,000 families will get a diagnosis of breast cancer because it's not just the woman who gets it, everybody in the family and friends in the circle are affected by a diagnosis of any cancer. That's 231,000. And at 41,000 women dying of breast cancer every year, that averages out if you just do the simple math of one every 13 minutes. We will be here 45 minutes to an hour. So you get a sense of the impact that has across the country. It is still a terrible, devastating disease. And it has tremendous implications for public health, for economics -- not just the human condition. We have to do much better than this. Now, interestingly, 70 percent of those breast cancers express a protein called the estrogen receptor that binds to that female hormone, estrogen. And we've known that if you target that, it has a significant survival advantage for most women. And we've known that since the 1970s. First ever molecular-targeted therapy for any cancer was tamoxifen for breast cancer. This shows you that the importance of the estrogen receptor because it shows you that estrogen-receptor-positive breast cancers and estrogen-receptor-negative breast cancers don't behave exactly the same -- the risk of the breast cancer coming back, which is distant recurrence in that panel, or the risk of dying from breast cancer. The patterns of those over a woman's lifetime are really quite different -- the risk of dying from estrogen-receptor-negative breast cancer is higher than estrogen-receptor-positive breast cancer in those first few years after diagnosis. After that, the risk begins to get higher for estrogen-receptor-positive breast cancers. And although those women often live much longer, they actually have on an annualized basis a higher risk of their breast cancer coming back the longer they live than those women who've managed to survive that long with an estrogen-receptor-negative breast cancer. So I said we can target the estrogen receptors; how do we do that? And there are basically two types of drugs that target the estrogen receptor. There are some that will bind there and stop estrogen binding there, and those are called anti-estrogens. And tamoxifen is a good example of that. And that's shown in this bottom part. So it's binding to the estrogen receptor so estrogen can't sit there. The other group are called aromatase inhibitors because they block the ability of the body to make the estrogen that would otherwise bind to the estrogen receptor. So you either block that protein that binds estrogen or you block the ability to make estrogen. And those two classes of drugs have been really quite remarkable in reducing the risk of recurrence and death. And that's shown here on this particular table, that the risk of recurrence is cut almost in half and the risk of dying from breast cancer if you have estrogen-receptor-positive disease is reduced by about a third. That's pretty good, but it's not good enough. Because you can see on that graph at the bottom here, you can see the survival advantage -- the overall survival advantage of taking tamoxifen -- but you can still see that there are plenty of women who don't survive still. Now, they may live longer and still die of their breast cancer, which is a fabulous thing to do. If you think about that top bar for the incidence is highest for women who are 50 to 60 years of age, if you could shift their survival 20 years, they get to see their kids get married, they get to see their grandkids grow up, they may even get to see their grandkids graduate from college. Even if they still died of breast cancer, you have transformed the lives of those women and their families. If we could make breast cancer a disease you died with, not a disease you died from, that alone would be utterly transformational. So think in your own minds how you might choose -- how you might choose to define cure. Because if you die of something else and you've had a good life, if we can get that far, that's a great step. Curing it is the last step, then. So think of it that way. So here's some basic questions. I'm going to speed up a little bit, and don't worry if you get left behind because I'll bring it all together at the end. And if you want me to -- if you get lost and you need to stop, just raise your hand and ask your question. So I posed a couple of questions here because I'm going to give you some insight into how we think about them. So I showed you that recurrence curve that some breast cancers can come back 20 years later after -- when there's been no evidence of disease at all and you think you're done. Are the ones that come back 20 years out the same as the ones that come back three or four years out? We don't know. So maybe we can begin to ask that question. And if we could find that they were different and we could understand how they were different, maybe we could take all those ones that recur in three and four years or five years and not have them recur for 20 years. And for many women, as I just said, you'd basically have cured breast cancer for those women because they die of old age or something else. So how you define where the finish line is frames the way you ask the questions, the questions that you ask and where you look for answers. So if we could learn something from any differences that we might find, we might have different ways of identifying the women who were at the highest risk of recurring early and we might be able to finds ways of not having them recur at all or having them recur to light that they would hopefully never experience -- have that experience. And the fundamental question is: If these drugs are so good for a high proportion of those women, why aren't they good for everybody? What is it about some breast cancers that have that estrogen receptor that we know we can hit and hit hard that still come back? Because if we could understand that difference, we might be able to cure them. So there's some of the questions I want to sort of pose. And then I want to show you where research is going. We can talk about the clinical implications in the questions. I can only answer those vaguely because I'm not a clinician. So let's ask the question, first of all, are all tamoxifen failures the same? Are those tumors that come back late different from those that come back early? And there are different ways to do this. And I wanted to give you a sense of the power of the tools that we have today that we didn't have 10 or 15 or 20 years ago. Because this is where the hope is. We can ask and answer questions in ways today that when I was a student getting my PhD I could not have dreamt of in one lifetime. And I'm not done yet. Don't think so. I've seen a transformation and an acceleration of our ability to create knowledge and turn that knowledge into actionable outcomes that can make a difference in the lives of people. I've seen that change so quickly and so much in the last 10 or 15 years. This is the most exciting time to be trying to find a cure for breast cancer. And it's the best time we've ever had to get there quickly. So this is an example of one of those technologies. This is a technology that allows us to take a little piece of a breast cancer and look at the expression of every gene that's present in that piece of breast cancer, in one experiment. So we can measure the expression of 40,000 genes in one biopsy from a woman. And if we can do that, maybe we can take biopsies from those breast cancers that will recur early and those breast cancers that will recur late and see if they're -- there's a pattern of gene expression in those two groups that predefines the outcome. So we'd be able to say which women are at the greatest risk of recurring early or late. And then we could ask why are they different and why do they recur early or late and learn something about the biology that would allow us to look at new ways of creating treatment. So this is a study we did where we did exactly that. We took breast cancers at the time of diagnosis but we had 20 years of clinical follow up. So we knew which women recurred early and which women recurred late. And we measured those 40,000 genes in each one of those breast cancers. What this shows you -- and you don't need to be able to understand the figures -- if you look at those two boxes in the middle, you'll see there's a red line and a blue line. So the red line -- each line tells you when that breast cancer recurred or that woman died. And you can see that the red line is very separate from the blue line and that the ones on the red line, their breast cancers came back early and the ones in the blue line came back late. So we were able to find a pattern of genes that told us whether that breast cancer was going to come back early or late. And we were able to find another set of data that was completely unrelated to our data -- this is a scientific question -- and show that we could do the same thing. So for us that told us -- our interpretation was, "Well, there's something different about breast cancers that recur early and breast cancers that recur late." Now, I'm not going to tell you that this is -- this tool is useful for telling any one of you whether your breast cancer is early or late because we didn't ask the question that way. We asked the question just to learn something about the biology this disease. So they're -- they seem to be different. That's good, we've learned something. So now we do what scientists do: We set up hypotheses. We say, "Well, if that's the case, what might explain those differences and how would we ask that question?" And so we took a different approach from others. We had 40,000 measurements on 140-odd breast cancers. And we said well, what do we really want to know? And rather than look for a single gene -- because we've always looks for single genes. And the best we could come up with was BRCA1 and BRCA2 mutations, and that's less than ten percent of all breast cancers. We have to think differently. And you think about what the estrogen receptor is, it controls everything that breast cancer cell wants to do. You take it away and those breast cancers -- some of those breast cancers die. It's that important. So what is different between those where you take it away and they die and those you take it away and they don't? So we're going to think of this as a system. It's called systems biology. We're not going to try and find one gene or one pathway; what we're going to try and find out is how does these breast cancers cells work as a system? How do they coordinate everything that they do to survive the stress of these drugs? And will that teach us about breast cancer? And so we have a network idea, that concept doesn't matter so much as where do you start looking? I mean, you've got 40,000 genes, you've got all the things that cells do; what do you really care about? Well, this is cancer. So we thought let's not ask all of the questions that we could, let's just figure out what it is that makes cancer cells live or die. Because if they die, we can go home. We're not there yet, obviously. But if they don't die and they never made another copy of themselves, that would be a case where a woman would die with breast cancer, not of breast cancer. So then we want to know if they're going to not die, what is it that makes them make copies of themselves when they shouldn't? So let's not worry about the other things, which are very important questions to ask about biology -- how do they spread, how do they get to other parts of the body, how do they live in other parts of the body -- let's just ask alive or dead or making a copy of yourself or not as a place to start. And so that's -- so that then constrains where you look in all of the data for the answers because you already know what some of these genes do. And they're not doing what -- anything that's related to being alive or dead for the cell or making a copy of it. So you can ignore those. And it gives you a place to look in a focused sense to learn something about the biology of the disease. So I've shown you that we could -- we had all these breast patients' tumors and we had all of this data. And we knew we could separate them. So now we knew which were early and which were late. So what are the genes that are different between early and late recurrences, and do they teach us anything about why they may be different? So you don't need to know the tools that we used. We used a computational modeling tool that basically said, "Okay, we know the estrogen receptor's important. Let's first find out all the genes that we think or all the proteins that we think are likely to interact with the estrogen receptor or interact with the protein that interacts with the estrogen receptor." And we're not worried about anything else. We'll just say what is that close in that data space to the estrogen receptor? And then when we find those, and there's about 50 of them that are -- no matter how you look -- keep coming up as being related to the estrogen receptor. We just look and see how are those expressions for those genes different between breast cancers that come back early and breast cancers that come back late? So once you have a focused question and you have the data, you can begin to look at it in different ways and answer a very focused specific question. So that's kind of what we did, and this is what we found. Basically, it's complicated. You kind of knew that was coming, didn't you? But also, it suggests that there are some relationships -- some genes that are always up, some genes that are always down, some that are always probably talking to each other no matter what estrogen-receptor-positive breast cancer you look in that would allow us to think if we were to knock down one of those, maybe we could stop all of this signaling from happening. So now it gives us a place to think about where we want to look to understand the biology and how we might want to think about where we want to look for new treatments. This is one way of looking at one dataset -- one or two datasets. So that's something. Now we've got some genes and some ways they talk to each other that tell us that we think that's important. So what if we take cells -- breast cancer cells -- and culture that we know can be killed by an endocrine therapy like tamoxifen or [inaudible] and we treat them and we look at the changes in genes at expression over time and we can look at how genes -- how cells respond quickly when they're first treated with an anti-estrogen. And that gives us another model. And what we find is some of the things that are present in the patient's tumors that seem to talk to each other also happening very quickly -- literally within hours of those breast cancer cells being exposed to the drugs. So are any of those hard wired later? Does the cancer learn how to use some of those to survive? So yeah, they kind of do. Because if you take the same cells and you treat them long enough so that a small number of them survive and they grow out and they're resistant, you can ask "How are the resistant cells different from the sensitive cells?" So what's now hard wired into those breast cancer cells that now are surviving the drug? And it's some of same genes that predict from early or late recurrence that are changed very early when the breast cancer cells are exposed to the drugs. They're now wired in hard. The cells have adapted their biology, their signaling to survive the drug. They've learned. We have to learn how they learn and what they learn to be able to stop that. So we know what some of these genes do. We know what functions they control within the cell that might allow that cell to survive, or die, or make a copy of itself or not. And when we start to put that information together in a systematic way, we begin to get insight into how the breast cancer cell works. And I'm going to tell you one way that we think it works. So these words on the far right in red and blue represent functions that cells perform. So apoptosis is a process of cell death. We like that in cancer cells. We want them to do more of that. Autophagy is a fascinating process. That's the cell's recycle plant. So when bits of it get old or damaged, it eats them up so they can be replaced and the cell can continue. But it doesn't waste the byproducts of what's chewed up; it uses those to live off. Because nature and life is very careful in how it uses its resources. So there's something going on here about alive or dead, whether that apoptosis piece is switched on or not, and whether that recycle plant is activated. And that UPR -- I'm going to tell you what that is in a minute, so just hold on. It doesn't get too complicated. So what we're really looking for now is how does the cell coordinate all of the things it needs to do to survive and to make a copy of itself? What all does it need to do just to do those two things? We -- that's the piece we care about. We know that when we give these drugs, they are -- the cells become stressed and some cells can't deal with that stress and die. This is good. But some cells are stressed by these drugs and they don't die. And that's bad. And, again, we're trying to understand the difference between those two. Now, we know that to do anything the cell needs energy. We all need energy. So one of the places we want to look is how the cell -- the breast cancer cell -- controls its cell metabolism. Because without energy, it can't do anything. We've known a lot about cell metabolism for a very, very long time. But we've always studied yeast, or simple cells, or normal cells. So a lot of what we know is how normal cells do what they're supposed to do. But these are cancer cells -- though don't do what they're supposed to do. So can we learn something about how they manage their metabolism so they have the energy to make a copy of themselves in order to survive? Hang in there. This is going somewhere. I -- I assure you. So we can do that, too. We can actually measure thousands of metabolites at the same time on a single specimen, just like we could measure all of those genes, we can measure all of the metabolites. And we can look at which metabolites are being used more frequently and which aren't, and that will tell us which processes and pathways the cell is preferentially using. And so some of these are listed here -- glutamate and glutamine. You see, we've actually known for a very long time that cancer cells are addicted to glucose -- the sugar glucose -- and to the amino acid glutamine. We've actually known that -- I'll show you in a minute -- for even longer than I've been here. That's how -- age-wise on this planet. That's an example of some things we've known for a long time. And we haven't known what to do with it. So the bottom tells you some of the functions that are changed. And you've got cell death, that's good. Cancer, well, we knew that. Glucose metabolism. So we know that there's so much -- that glucose metabolism must be important in how these cells become resistant and evade the anti-estrogens. And autophagy, that process, that recycle plant process, that's also been upregulated in these cells. So now we have to think "How are they connected? And what way does that connection allow the cells to survive and make copies of itself?" And I've shown you that we've got -- we can measure the metabolites and we can measure the genes that are expressed. Well, we can take those two types of data and map them onto each other and begin to understand how the cells uses its proteins and its genes to regulate its metabolism. Now we can begin to understand how it functions as a system and how it makes choices. And we find things like cell survival, we find insulin and IGF, which would regulate glucose metabolism normally are also changed. They do other things. And we see that some of the high-energy metabolites, the levels of those are different in the cancer cells that are sensitive and resistant. So this is what we've known since about the 1930s. So when my mom was born, this guy, Otto Warburg, was figuring out that cancer cells are addicted to glucose. And they metabolize glucose in a way that's very, very different from most -- but not all -- but most normal cells. Because cancer cells -- cancers don't have a proper blood supply. So they don't have all of the nutrients and oxygen and all of the bits and pieces they need as easily. It's not as easy for them to get as it is for the rest of our body. And so there's not enough oxygen. And normally that would change the way cells would metabolize glucose, but cancer cells don't care. They've learned to do this whether there's oxygen -- enough oxygen present or not. And they just love glucose. And glucose gets broken down naturally to produce the chemical energy that the cells use to build everything. One of those molecules is called ATP. And you don't really need to know much more than there's a chemical that's made from glucose, that's a byproduct of breaking up glucose, that the cells use to store energy, and then they can release it to build other things. So we looked at whether the glucose levels are changed in sensitive or resistant cells and whether that's effected by the anti-estrogens. Because that's fundamentally -- if we're changing their ability to make energy, maybe that's one of the reasons they're dying. It turns out that that's the case. But what's really interesting is actually on that ATP graph on the right. You -- I'll tell you what it says so you don't have to worry about whether you can read it. It says if you give an anti-estrogen to sensitive cells, they take up less glucose and they have less ATP. They don't have enough energy to do everything. And what that normally does is first that causes the cells to stop making copies of themselves. And if you can hold that glucose levels low enough and the ATP levels low enough, some of those cells will die. They -- they just can't survive any longer. The resistant cells have figured out how to take up glucose and make that APT even though they still have the estrogen receptor present and the drug is present. They don't care anymore. They've figured out a way to get around that. So we don't quite know yet how they've done that, but we know that they've done it. But the other thing that told us we needed to look elsewhere, too, was -- and that's these panel on the far right -- the cells that are resistant and are growing happily at the same rate as the cells that are sensitive when they're not being inhibited actually have less ATP. They don't need as much energy. Well, why do resistant cells that are doing all the same things as sensitive, normal cells are, why do they need less energy? That's where the recycle plant begins to come in. So they're clever little suckers. So what happens in a cell if you don't have enough energy? Well, the first thing is you actually can't make and fold your proteins properly. You need proteins through all of the business that the cell needs to do. And cells have across evolution been exposed to very different environments when their nutrient supplies and their ability to make energy was constrained. But they still survived because they developed a system to deal with not having enough energy to fold your proteins. It's called the unfolded protein response -- that's that UPR thing I promised I would tell you about. And you can find this in yeast cells. It's a little different in mammalian cells, but it's not that different. And it's a damnably clever system, as you would imagine. Because if you don't have enough energy to fold your proteins and you want to survive first -- survive first, grow second is a sort of priority for the cells. Normal cells have that priority just like cancer cells do. And if normal cells are able to do this, why couldn't cancer cells use this as a way to survive? And what the unfolded protein response does in this cell is it says "I have a problem, I can't fold my proteins properly. Let's make less protein, figure out how to get everything back to normal, and then we'll make a copy of ourselves." In the process it doesn't want to die. So it also sends a signal out to the mitochondria, the energy piece in the cell. It says "Wait a minute, we've got a plan here. I know we have a problem; we're not going to die yet. So signal, just don't die yet because we're going to fix this by making less protein, making only what we need until we can survive. And then we're going to go off and we're going to make a copy of ourselves." And that unfolded protein response coordinates all of those decisions in the cell. And cancer cells can use the same thing. And that takes us back to this little model that I briefly went over and told you none of the details. Because what that model from our study said was that seems to be important here. Of all the things that this -- that the breast cancer cells could do to survive the drugs that we're giving them, they seem to be using this unfolded protein response. And we learned that one of the coordinating signals that comes out of from the unfolded protein response also coordinates the recycle plant signal. So now we're beginning to see how what the cell's doing doesn't have enough energy, so it's not trying to make copies of itself. It's going to survive first. To do that, now it doesn't need as much energy because it doesn't have to make a whole other cell to make a copy. So it can live with a lot less. And at the same time it's sending a survival signal to allow it to see if this is going to work or not. And that's what these resistant cells do. They upregulate at the same time that recycle plant because there they were happily going along, making lots and lots of copies of themselves, and now they don't need to. So all the machinery that they had to make another copy is superfluous. They don't need it anymore, so they just recycle it. And they kind of live off their little bit of belly fat, if you like, and find a way to survive even when all their metabolism is being shut down. And some of the cells next door haven't figured this out and they die. And what happens to the bits of the dead cell? The one that's alive just sucks them in. So they start to feed each other. So they start to feed themselves off what they don't need anymore, and they start to pull in the nutrients from the cells that are dying next door. So it's really an ecosystem. It's a whole system where all the cells are talking to each other and working together and some are dying. And because they're dying, they're actually helping some of the other ones to live. Cancer is smart. And this simply shows -- so I'm just about done. And I'm going to live you an analogy of how we've come to this to understand just these basic principles and why that's beginning to change the way we think about dealing with breast cancer and dealing with particularly this drug-resistant -- type of drug-resistant breast cancer, which is in effect ultimately up to 70 percent of all breast cancer patients. Imagine a car. Okay. You could have Mini, you could have a Maserati. I know which one I want. But it doesn't matter. The basic principles of the internal combustion engine that drives the Mini and drives the Maserati are exactly the same. What's different is all the bells and whistles in the Maserati that's not present in the Mini. But all the control systems -- the brakes, the engine, getting the fuel in -- all of those things are basically the same. And that's kind of a little bit like looking at cancer and normal cells. The cancer cells are using what they've inherited as from their having been once normal to allow them to survive when they're cancer and we're trying to kill them. So think of where we are on a car. So we kind of know where to put the key in the car. And it's like the estrogen receptor. It's kind of like the switch that turns on everything. And if we turn it off, notice that car's not going anywhere. It's stopped. If you leave it stopped long enough, it rusts away and it dies. So we know where the key goes and we know that if we mess with that key, we can cure some breast cancer patients. So it's a great place to start. What happens, then, when that key gets broken and turned on all the time? So what it's doing is it's turning on the engine. It's firing up the engine and it's going to make a copy of itself. Now, we know how cells make copies of themselves. We know how yeast cells do it. We know how normal cells in humans do it. So that piece of what happens in cancer is often very much the same. What's not the same is the signal between the switch and the engine. That's what's got changed in cancer. So that now begins to tell us where to look to understand in more detail, a much finer place to start looking to understand how these cancer cells are different. We know, like, the car ain't going anywhere without gas in the engine. And the cancer cell isn't going anywhere without the same gas in the engine. It makes it differently. It's like it's got a different grade of fuel, if you like. But it's still ultimately the same energy source, the same fuel source. If we could understand how that was different, we might be able to stop it from making its energy. And in a sense that's what these anti-estrogens do when they work: They turn off the switch and they take away the fuel. The real thing is how does that happen? Now we know where we really need to focus. And the basic principles, when you think of it that way, are on my last -- or my almost last slide. So this is how we think it works as a system. This is where it all comes together. You give an anti-estrogen, you don't take up enough glucose or glutamine, fatty acids, but you don't have what you need to have enough energy so you can't fold your proteins. You can't fold your proteins, that activates the unfolded protein response. And that coordinates the don't die yet signal and lets turn up the recycle plant because we're going to live off that for a while. And maybe we can pull some other things in from outside. That's the way the integration works. That's where if you look at it as a whole system, you see a very different picture than if you just try and find a single gene or a single mutation that you think might drive the whole system. Because the estrogen receptor gets mutated in some breast cancers. And that's not the whole answer. It's when you look at it as a system that you begin to see now there are some vulnerabilities. There are vulnerabilities in how the cell makes metabolism. There are vulnerabilities in how it coordinates that -- that recycle plant. We could turn the recycle plant off. We could turn that off, we could turn down the cell metabolism, and we might get a completely different response using drugs we've never thought of using before. So that's kind of the bottom line. And what have I told you today? Because I've covered a lot of ground, and I've probably talked too long. We have to fix this problem. We have to understand how this works. The cancer doesn't exist as a single cell; it exists as an organism almost within the patient. It talks to itself. The cells talk to themselves. They use the host's response in some cases to survive. At the same time the host is trying to eliminate the cancer with its immune system. Why hasn't that worked? That's another piece of the puzzle that we haven't cracked open yet. Because if the immune system worked, you'd never have cancer. They would just be identified as being foreign or screwed up and eaten up and removed. That's obviously another piece of the problem. So there's a lot more to think of. But if you start thinking of it as a system, you begin to ask "Well, what is it that's in the immune system that's talking to the breast cancer?" You know, just think why does it not work? You look at the question in a different way and you see different parts of the jigsaw puzzle. With one woman dying every 13 minutes and 70 percent having this biology when they start, we need to do something that's fundamentally different. We have drugs that work for some women, we have drugs that kind of work for some more women, and we have the same drugs that don't work at all for another group of women. We need to be able to do better. And there are drugs coming along that are playing in this area that are probably going to be very helpful. We have drugs now that are called CDK/46 inhibitors. What that means is they're very good at also turning off the proliferation signal. So when the anti-estrogens come along and shut down some but not all of the cells, these other drugs come can come in and shut the rest of them down. Don't know if they'll cause them to die, but maybe if they're shut down long enough, they will. We have the tools -- and I've given you just an example of a couple -- to ask the questions of these systems in ways we could never do before. Our ability to generate data first, and then translate that data into knowledge, and from that knowledge identify the actionable items that can lead us to better preventions and better treatments for breast cancer is moving very quickly. And it's very exciting. And the potential for making a big difference is greater now than it's ever been in any time in the past. Those are tremendously exciting things to think about. We have the ability to do this. Now is the time to do it. We shouldn't wait any longer. We shouldn't constrain the resources that we put to curing this disease. This is a time to do the opposite because now we have the tools that will allow us to answer this question in ways we could never have done before. Obviously, what I've told you involves a lot of different people, and it's nice that I'm able to put their names up there. And you're welcome to read them. But there are names that are not up there. And they will never be up there because I'll never know their names. I'm not allowed to know their names, and that's fine. It's fine that I don't know their names; it's not fine I can't thank them. Those are the women who gave us the tissue in the first place, some of them 20-odd years ago. They're not here anymore. Some of them died of their breast cancers because they had early recurrences. Some of them died of their breast cancers later because they had late recurrences. Some of them probably I'm certain are still alive. I don't know their names. I can't thank them. Without what they did, we could not have got even started on this pathway. So the people that are most important are the patients who contributed to the study in the first place. Thank you. It is so important to hear from patients what their experiences are, what their needs are, what their questions are. It's not just about the research. And it's just lovely to see someone say "I had it in the 1970s and I'm still here." Because we'd love that to be the story for everyone. Now, can we take what we've learned and make it -- and turn it into new treatments for prevention, or to eliminate that cancer, or make it never come back? I think we can. But we started to think about how we do that very differently. So the way that -- I use the example of a car. So the same way of thinking is the way we're beginning to change how we -- I think we should be thinking about how we combine drugs to get a better effect than just randomly or following a logical linear way of thinking. This is a non-linear way of thinking. If you really wanted to stop the car, you'd break the switch, you'd take out the battery, you'd drain the fuel tank. We've kind of thought of different ways of breaking the switch, but we never thought of "Okay, I should really take the battery out and drain the fuel tank as well because, you know, we want to make darn sure this cell can't function." So in the past -- and it was a fine way to go -- and the CMF therapy that you got is a good example of we took drawings that had different mechanisms of action and didn't have the same toxicity so we could give them in combinations at the highest doses we could. And that's fine, but it's -- it's a practical, pragmatic but not hypothesis-driven approach. It's what you can do. It doesn't mean it's what you should do. Sometimes it is. Sometimes there's better ways. So we're trying to think differently. So let's not just take three drugs like that because they have different mechanisms of action. They're not -- not that different. [Inaudible] are similar in a sense. But we want to now target different parts of the whole system. The more pieces of the system that we can knock out at once, the less chance that cell has to figure out how to survive. And that's a different way of thinking because we had to understand what those functions were, how they might be wired, and talk to each other before we could even think of doing it this way. And we still don't know enough to do this rationally yet. But it's taking -- it's allowing us to begin to think differently. And sometimes that's just enough. You think differently, you may get to a place you never thought you'd get to, but it's still the right place. We do know that there are different types of breast cancer. We know that estrogen-receptor-positive is different from estrogen-receptor-negative. We know that -- that a mutation in a gene called HER2 or ERBB2 also creates a special group of cancers that we can target by targeting that growth factor with drugs like [inaudible] as you probably heard. So at the very least there are those that have the expression of the estrogen receptor, those that have expression that mutated oncogene HER2, and those that don't have any of those. And the other one that goes with the estrogen receptor is progesterone receptor. And that's why that last group is sometimes called triple negative because it doesn't have estrogen receptor, progesterone receptor, or mutated HER2. At that level there's at least three. Once you start asking "Are there other groups within that?" then is opens a whole can of worms. There are, depending on what you look for. Different mutations you'll find are scatter in a different way. Other pathways that are differentially -- you'll find that as subgroups. Ultimately, for the moment the type of treatment that a woman gets is determined by whether or not there's the estrogen receptor there to target, whether there's HER2 there to target, or whether there's neither of those to target. And that's the triple negative, and they unfortunately have the highest risk of recurrence and death in the shortest period of time since diagnosis. And we only have chemotherapy for the moment for those. And they seem to be a quite heterogeneous group of breast cancers. And it's about 12 to 15 percent of all breast cancers. The subgrouping is useful in my personal view -- and this is only my personal view -- if it teaches us something about the biology we didn't know that leads to an actionable outcome that allows us to identify which women should be treated with which treatments because that's the best for them. I'm not sure we've quite got there yet with a lot of these subtype analyses. We can say from some of them that this woman has a worse outcome likely or a really good outcome likely. So some of the tools are good in a prognostic sense. And the real value there is who not to treat. Because some of the very early stage breast cancers like I described [inaudible] if the surgeon gets in and the radiotherapist gets in and it's gone, you don't need chemo. So why would you take it? It's not a very pleasant experience. So the real goal there is if your risk of recurrence is so low, why would we use chemo at this point? So those are the sort of questions that we're able to do better at. But which chemo should you get? We're not there yet. What new drugs, what combinations of current drugs would give us the best outcome for you versus you? We're not there yet. But those are exactly the directions that we want to go in. We'd like to be able to say that -- that your cancer is unique in some way, and we understand that uniqueness, and that uniqueness is a vulnerability in that cancer that we can target. That's the sort of precision medicine concept -- one way of expressing the precision medicine concept. I think we will find better ways of using the existing drugs first, I suspect. And we'll see the benefits of that earlier simply because we don't have to wait for a single drug to be approved and sure that it's safe and efficient, and then identify the patients that need to be used, and then figure out how to use it in combination with other drugs. That's a long process. And we need to keep doing that because we need to find drugs that hit different parts of that machinery more effectively. From where I sit, we have drugs that target metabolism, we have drugs that target proliferation, we have drugs that target survival. We've never understood how we should use those or whether they're the right drugs to hit those targets if we were to. But now we can build mathematical and computational models with the data that allow us to ask those questions. And those questions because they're done in the computer can be asked hundreds of thousands of times and very quickly and make predictions as to what we can do quickly to test first in cell culture models and then in preclinical animal models to see -- make sure that those drug combinations are safe effective and then quickly get them into women because the drugs are approved. That is -- so that's a drug repurposing or redesigning the cocktails. And there are some really interesting clinical trial designs that I won't go into today because I'm not a clinician and I wouldn't be able to answer your questions. But there are some really powerful new clinical trial designs that are beginning to try and get at that, where women can come in and they can get treated with one set -- series of drugs, and then upon recurrence they automatically get into a different box. We think that there might be ways of better selecting when a woman gets what drug and what box to go into next. And so these new designs which are using existing drugs -- and a small number -- will probably teach us how to do that better. And we'll be ready, then, to do those experiments -- to do those trials in women once we've completed the experiments that tell us how to mix and match. So my prediction? I -- I make this as a prediction for my lifetime, and since when it's over, I won't be here to know I was wrong, I think we will make estrogen-receptor-positive a disease that women die with but not of in my lifetime -- I think. Triple negative? A little longer. If there was a BRCA12 mutation, the risk of ovarian cancer is also increased along with breast cancer. So that's the Angelina Jolie story. So -- and that's -- I mean, again that's a very personal choice for every woman in consultation with her physician, removing the breasts and then removing the ovaries to eliminate the risk of both breast and reduce -- greatly reduce -- the risk of breast and ovarian cancers. So, again, that's -- we have -- we have professionals who help women and families work through those and find what is the right solution for them. So that's probably the rationale for that. So HER2 is a protein that sits in the membrane of -- of breast cancer cells, and it's mutated in a way that means that it's constantly sending a growth signal, a proliferation signal, a survival and proliferation signal to the breast cancers. And they are -- a significant proportion of the ones that have that are depending on that signaling in a way that's similar -- conceptually similar -- to being driven by the estrogen receptor, not as being driven by HER2. And so if you come along with drugs that block that signaling, the cells can't survive and they can't proliferate. And about half of those have no estrogen receptor and about half of those have estrogen receptor. The ones that don't usually get a chemotherapy at some point. The ones that do can still take tamoxifen or letrozole -- an anti-estrogen aromatase inhibitor -- and they will sit gel some benefit from that even though they've also got that driver mutation in the HER2 gene. So it's an interesting intermediate biology in one sense and a completely different biology in another. >> Tomoko Steen: Please join me thank you for [inaudible]. [ Applause ] >> Robert Clarke: Thank you. >> This has been a presentation of the Library of Congress. Visit us at loc.gov.