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Current time:0:00Total duration:11:34

Systemic thinking about cancer

Video transcript

this is Sal here and I'm I have dr. David agus visiting the office and I want you to introduce yourself because you have kind of an interesting life interesting life is scary but I'm a professor of medicine and engineering at the University of Southern California I treat cancer patients and I have a lab that looks at new ways and technologies to understand and treat cancer and that's what's really interesting the fact that you're professor of both medicine and engineering and I guess that's kind of all we're going to touch on a little bit here yeah and so so so this is clearly a picture of eggs why are we looking at eggs well if you I gave you those eggs and I put them in your office and I said come back in three weeks what would you have if if I they they would go bad I'm not gonna fridge I'm assuming you have a run back exactly but if I was clever and I change the temperature your office to ninety-nine point five degrees Fahrenheit and I rotated those eggs three times it has to be an odd number then at the end of three weeks I'd have a chicken at the Jay so so this that's what this other picture is you'd have this so you could either have a rotten egg so this kind of crazy mess smelly thing or you have this cute adorable chicken although they call babies chicks chicks a babe or chick yes yes so a small change in temperature and gravity goes from chaos to order right and so we're going to talk in a minute about cancer and all the chaos that's involved with it but realize that that egg I change the temperature and the gravity and I went from chaos to order so while it will seem incomprehensible and unable to model cancer you're going to start to see little changes can have major effects I see and this is with a little bit unintuitive so when we think about things like cancer I mean cancer is not the only one we imagine we imagine that we just have to kind of we just have to kill it we just kind of have to take it out but what you're saying is hey maybe there's these subtle things the analogous to rotating an egg you know three times and getting the temperature just right that can make it make it automatically do different things exactly to me cancer is a verb not a noun so your answering answering when you have cancer it's not that you have cancer York answering and so my goal is to change your state of your body from AK answering to a health Inc and so the first question is how do you quantitate the state how do we say who and what you are and so technology is giving us the opportunity to do that as we go forward right I just want to get my head around that because that's just you know you never hear that word cancer I think you've probably invented that word this so are helping and and it's it's from the ideas once again when I imagine cancer I think this is the way most researchers think about cancer is this the set of cells have just gone berserk and you have to remove them or kill them somehow or stop them from spreading and and what you're saying is no there's something going on systemically in your body that is cancer it's allowing the cancer to thrive that's it so you just your first definition of you know something you have to cut out a different organism that's bacteria that's an infection right so it's something from the outside comes inside of you I give you the right antibiotic it doesn't care if you're a man or a woman you're 6 feet or 3 feet if that antibiotic targets the bacteria it goes away the difference in cancer it's your own cells that have gone a little bit crazy right and so we have to change the interaction of the body and the cells in order to make that patient better very different than something without this is within I said I'm just you know there's all sorts is fasting because there's all sorts of parallels and I guess everyday life depending on your own what you believe but you know some people if there's crime in an area there's one point of view that you either police it you have to arrest all the criminals but but then hey maybe the criminals keep coming because there's certain environmental factors maybe there's just a lot of poverty and there's lack of education and there's so you're saying hey let's look at the things systemically that's not saying to just put some lights in the area put some police driving by then all of a sudden the crime level goes down right right it's not just about arresting the criminals exact about prevent let me tell you about a clinical trial that was done a couple years ago is the coolest clinical trial and they took women after optimal therapy for breast cancer and these were women who are pre menopausal so a really aggressive breast cancer half of them after treatment got placebo and half of them got a drug that builds bone and trusted sources let me write this down so this is breast cancer so these are these are people these are young women with breast cancer right right and so and half got a placebo which means just like a sugar pill sugar blip and you give that to patients just to make them think that they might because sometimes a psychological impact right and this was ethical and it's very important to talk about whether was ethical or not it was ethical because they already got their treatment for breast cancer right and normally in those women we just wait and hopefully they're cured and we see if it may recur right so in those women we divided them into half and if we gave this pill they were able SIBO right and half we gave a drug for osteoporosis that builds bone osteoporosis porosus I'll save you why are you wasting someone breast cancer is time by giving him a drug yeah got a targets bone right right right reason is breast cancer metastasizes to bone and metastasize it spreads to bone that's right all the cancer just goes that's right it goes to the bone it lasts the bone right so the argument if I change the soil the seed won't grow so remember when you have a garden you can either give fertilizer make that soil so tomato plants love it right right right and so that's what we're doing here we're making the bone different right and so once again sits the system thinking is that before if you have these breast cancer cells that are just growing the view is hey let's irradiate them let's slice them out let's get chemicals it'll be toxic to these cells and kill them what you're saying is cancer really starts to to become a real negative once it spreads and what you're saying is let's keep it from spreading where maybe where it's most common to spread which is in the bone so instead of so before the bone drug the cancer spread that the cancer could kind of take root could take root in the bone and then start spreading and metastasis or this is what metastasis is and instead you're saying maybe if you have this special drug this osteoporosis drug it makes the bone that was stronger and less susceptible to this type of thing and then it just that that won't be able to happen exactly right right fascinating so at the end of that trial the cancer recurrence was reduced by 40% at the end of that trial new breast cancer so a separate breast cancer because once you have one breast cancer you can get another breast cancer that was down by 35% so this notion of changing the systems remember this is a drug that didn't even touch the breast cancer had a dramatic effect in the survival of these young women right so again it just makes us a whole new way of thinking about disease right right and so I guess what would be the so if we were to put words on things the way that most of people think about disease right now you call it can I'm a reductionist or we're just trying to focus on one narrow part of it they're trying to focus on this thing right over here and you're you're advocating for kind of a more systemic way of thinking about it where you think about everything that this might involve or that might affect it it's so wild is that for the last several decades we're trying to focus on the individual cell and then the individual gene and then the piece of a gene and we've forgot to take that step back and look at the whole system and so remember that cancer is your normal cell that's gone a little bit crazy right so we have to model that whole system and figure out a way to control it so the cancer won't like it Wow fascinating fascinating and then you actually have we have pictures of what some of these things look like so what is this right over here so this is a liver that's taken out of a patient right and the white spots there are colon cancer that's metastasizes again spread to the liver right so it's it's a cancer that grew up in the colon at some point it was able to spread and kind of liberate itself and then attach on to the liver and that's what it's metastasized to the liver now it's kind of growing in this it looks at least from this picture kind of a cauliflower like shape exactly exactly and then if I showed this to a surgeon or someone who normally operates on livers they would know right away hey that looks like colon cancer gone to liver right right if you look at the next picture on the right that's colon cancer inside of a lymph node under a microscope and this is these are these are the lymph those are the normal limps limbs and this right here is the colon cancer exactly okay so any pathologist would look under a microscope and they would make a diagnosis say hey this looks like colon cancer gone to the lymph right and on the bottom is a different way of looking at cancer which is a cat scan so this is basically a three-dimensional x-ray why took a slice right in the middle of that person's body right and those translucent areas in the middle there are colon cancer metastases this those darker areas yes okay and so what's amazing is that's in their liver colon cancer looks a certain way where I live known in the liver on a cat-scan right and it always looks that way right the body doesn't care what the underlying genetics are because the genetics are dramatically different patient to patient to patient but it always looks the same Izu so somehow evolution is selecting out for phenotype which is what things look like not necessarily for genotype which is their actual the DNA that makes up exactly our right so we're focusing on genotype phenotype is very important and it's going to give us some understanding over time we have to also take that step back and look at the phenotype look at what it looks like and trying to change those interactions remember if a patient has early cancer right we've learned a lot in the last 10 years right so if you have early cancer and I cure you with surgery the day before surgery I can always find cancer cells in the blood even though you were cured right so the old days we thought well you have to wait till it goes out through a blood streaming gets out there that's wrong right it's can it live outside that original organ I see so there's someone who's cured or they're they're not cancer is actually cancer in their blood there's but because they're healthy now or healthier or they're helping or I guess everybody that cancer isn't able to take home and those cells they can't live anywhere but the colon faster so it looks into this experiment this is the wildest experiment they took a mouse yeah and they took breast cancer and they put it in the left breast in the right breast yeah and they colored them red and green the cells right they waited a day they went back and the cells were half red half green half red half green because we always thought of cancer as something in one local spot right it really is a disease that keep going through the bloodstream and it likes those breasts that's why I keep going back there so that's interesting when I always think of metastases and I can never say say the word I always imagined it okay that's the cancers it's finally gotten to the lymph network it's finally gotten to the blood vessels and now spreading what you're saying that there's actually often cancer that has gotten to the to the transportation networks off the body but it has still not metastasized because it's not able to take hold yet exactly laughs exactly and over time we're going to get the technology to interrogate those cells to say hey this one can take hold here therefore I have to change where it would take whole right we're just at the beginning of that technology that's going to change everything and the reason why we're looking at looking at these that the fact that the colon cancer starts in the colon and this is how it looks when it spreads to different parts of the body what you're saying is is that we shouldn't maybe be so fixated on just the DNA of colon because of colon cancer because it can be very different from one patient to the next but maybe on the kind of its macro behavior its phenotype how it looks and how it behaves and that that way we might be able to it'll give us clues maybe on how we can change it exactly fascinating thanks a bunch this is very interesting it's great