Gregory Morgan

Cancer Virus Hunters

Air Date: September 27, 2022

Stevens Institute of Technology science historian Gregory Morgan discusses his new book Cancer Virus Hunters: A History of Tumor Virology.


HEFFNER: I’m Alexander Heffner, your host on “The Open Mind.” I’m delighted to welcome our guest today, Gregory Morgan. He’s author of the new book “Cancer Virus Hunters” and he’s a historian of science at the Stevens Institute of Technology in New Jersey. Welcome Gregory.


MORGAN: Thank you. Thank you for having me.


HEFFNER: It’s a pleasure. I know you’ve been working on this project for many years. If you go into the index of interviews you’ve done, you see that, sometimes multiple interviews over the span of multiple years. In the process of writing about, chronicling, hunting, the cancer virus what changed, you know, because the science is protean, it’s evolving about like deciphering or detecting what are the viruses that cause cancer. So, in the course of the research for this book, what actually changed, in fact that you were learning new things as you were writing?


MORGAN: Yeah. So the book is sort of an exploration of about a century of research going back to the beginning of the 20th century. I think one of the biggest changes that happened was at the in the beginning, people were very skeptical that viruses could cause cancer. The mainstream view was that that was kind of a fringe theory and that there were better explanations of the cause of cancer. And then as the century progressed the tide kind of turned and people became aware that at least some cancers were caused by viruses. And it became a more productive area of research for a lot of people.


HEFFNER: So, take, give our viewers the historical overview of this story, of virus hunting. Who was the first person to investigate the cause of cancer as a virus or as viruses?


MORGAN: Right. Well, I begin in the story with a, an American physician, scientist called Peyton Rous. He worked at what’s now Rockefeller University. And he was interested in what he called experimental pathology, like why do we have certain pathologies, and can we explain it? And at the time, the nature of cancer was pretty mysterious. No one had a really good theory about why people got cancer, what caused it, what actually it was, or were there any ways of stopping it, or treating cancer. And so it was sort of a lucky accident that started his research. A chicken breeder brought him a chicken that had a large tumor in its breast. And he decided he would investigate this. So he took the tumor out of the chicken, and he ground it up, and then he started doing experiments on it by injecting it into other chickens. And he found that he could create tumors in other chickens from an extract from this original tumor. So that was the beginning of it. So there was at least some tumors in chickens that could be caused by a liquid that he extracted from other tumors. This, this started in 1909 and he worked on it for several years. He eventually gave up working on it because, partly because the tools that he needed weren’t invented yet. And he didn’t call it a virus. He was quite, he was a little worried about calling it a virus. He just called it an agent. And it was unclear of the nature of the agent either. Wasn’t sure if it was a biological agent or maybe it was a chemical agent. So he was the first person that started it. And then others joined in. There was some work on mice and some work on rabbits where we found tumors and rabbits that could sort of do the same thing. And molecular biology was sort of starting up in the forties and fifties. We had electron microscopy invented so we could actually see what was causing, what was in the fluid that he had that would cause the tumors, and that looked like it was a small spherical object that we today would call a virus.


HEFFNER: Now differentiating between the theory and the fact, what can we say now, definitively, unequivocally is fact as it relates to the cause of cancer and the role of viruses and what percent that is?


MORGAN: Yeah. So I think that the conventional view now, which is, is that cancer is caused by mutated genes. And they’re often called oncogenes. And the causes of those mutations can be various things that can be environmental. It can be an infection from a virus that brings you those genes, and which genes are mutated that cause cancer can be de…were first determined by looking at these viruses, because it turned out the virus that Peyton Rous isolated had picked up a gene from an earlier chicken infection, and that gene mutated, and when it was turned on in chicken cells, it would cause tumors. So that was the first oncogene that’s called SRC. And a number of people got a Noble prize for learning more about what SRC did and why it was this particular stretch of DNA that mattered.


So we definitively know, I think, that cancer involves mutations and particular genes in our genome. And yeah, there’s a number of different causes of them. I mean, interestingly, we now have kind of brought together two different views of, of cancer. There used to be a view that it was a cause from the outside of us, right? The environment caused cancer. And a competing view was that it was actually caused by something inside of us, an internal view, something gone wrong with one of our, you know, homeostatic systems inside our bodies. Mutated DNA allows us to sort of unify those two different views because obviously it’s the D, it’s our DNA in our cells that’s the problem, but that can be caused by things from the outside too, like smoking, or, you know, sunbathing, or just generally aging.


HEFFNER: And it’s that enigma that has puzzled people for decades and centuries. The fact that there is not a magic bullet in the cure or treatment of cancers. But are you able to specify when it comes to the mutations, because all cancers derive that way, right? As a result of, of cells basically gone awry, right? Are you able to decipher, like what percent of those mutations are a result of the viruses specifically?


MORGAN: Yes. Actually all those estimates that, about a fifth of all cancers are caused by viruses.


HEFFNER: You said a fifth,


MORGAN: A fifth, yeah. About 20 percent.


HEFFNER: And the other, the other 80 percent?


MORGAN: And the other 80 are going to be other environmental mutagens. Yeah. And maybe even some of the genes that you inherit from your parents that could be mutations that predispose you to cancer. Yeah. So it’s going to be more of an environmental explanation for most of those.


HEFFNER: And is it…


MORGAN: And some of the viruses, some of our viewers may have heard of like human papilloma virus, which causes cervical cancer or throat cancer. There’s also a hepatitis B virus, which causes liver cancer in some people. And you talked about a magic bullet, and in some sense, we have a magic bullet for these now, too, because we now have vaccines for both of these viruses. So if you get vaccinated against them before you’re infected by the virus, you can stop yourself getting cervical cancer.


HEFFNER: Well, in, in a sense, are these, have these been the most accessible targets, the 20 percent we’re referring to because the other 80 percent is more of mysterious origin and harder to kind of get to the bottom of. And so how has this, this generation, or these generations of virus hunters informed the way, was my next question to you, that we’re treating, first I want you to talk about the 20 percent, because I think that’s easier to understand. But then the other 80 percent too.


MORGAN: Right. So I guess it’s two parts to that. I mean, if, if 20 percent of our, of cancer is caused by viruses, then if we can vaccinate ourselves against those viruses, make good vaccines, then we can effectively cure cancer for that 20 percent. That won’t do anything for the 80 percent, of course. But what, what, what the study of these viruses actually did was give us like a foothold into what parts of the genome are broken in cancer cells. So in theory, that should lead us to having better therapeutics since we know what we’re sort of looking for now, and it’s sort of narrowed the search for what type of drugs might be useful. If we can target some of these genes that are broken. Then in theory, we could come up with some, some good therapeutics. We’re not quite there yet, right? But I envisage, this is what 21st century biomedicine will be doing is getting better drugs that will target some of these broken genes, or even, even genetic therapy where we introduce like correct genes and to replace the broken ones.


HEFFNER: Can you explain to me again how the virus hunting, the understanding of the viruses you were making, the argument that it in theory should help with the 80 percent?


MORGAN: Right.


HEFFNER: And it, and it has to do with how cells break down and studying how the viruses cause those mutations is that right?


MORGAN: Yes. And also that, because when a virus takes over a cell it turns that cell into a factory to make more viruses, right? That’s basically what a virus does, right. It just invades the cell, turns it into a virus factory that makes more viruses, they escape, and they infect more cells. The way in which the virus genes and proteins interact with the cellular proteins is really important for the virus. But it also is important for scientists because they can see that cellular proteins that interact with the viral ones are the important ones in what’s called the cell cycle, making a, making a cell, basically reproduce at the right rate. And in cancer cells the cells are not reproducing at the right rate. They’re reproducing too fast.




MORGAN: And those proteins that interact with the viral proteins are in every cell we have. And they can go awry when, when infected with a virus say, but also just on their own. For other reasons.


HEFFNER: Now, when you hear about immunotherapies, or the idea of creating a virus, that’s going to correct me if I’m wrong, that would potentially be equipped to kill that 80, you know, the 80 percent,


MORGAN: Right.


HEFFNER: That you could, you could build a virus to kill the cancer cells or the cancer from forming in the first place. But it, when you take, take us through kind of the idea of immunotherapy. And also this idea of whether or not you could create viruses that in essence serve as a remedy that could combat that 80 percent. Right?


MORGAN: Right. Yeah. So I called my book “Cancer Virus Hunters” partly because I think we, the last century has been sort of the hunting phase of virology, or tumor virology. But now we’re moving into what I call the agricultural era, where we can re-engineer viruses to do different things and to sort of serve our purposes. So in immunotherapy, we use our immune systems to try and attack cancer cells. But we can also do what’s sometimes called viral therapy where we re-engineer a virus so it only attacks cancer cells. That would be the goal. And it leaves healthy cells alone. It doesn’t do anything to those. So there’s maybe many ways of doing that; many ways of reengineering the virus to do that. It could be that cancer cells of a particular type of cancer express a protein on their surface. And then you, you make the virus so are only attacks that protein. Or because cancer cells are, have broken oncogenes are inside them, right. Genes that make the internal composition of the cell different, you can make viruses that’ll only replicate in those types of cells, in theory. And there’s a number of people doing this. I think I did a search recently. There’s about 50 clinical trials currently going on at the moment to see if they can successfully make a virus that will only attack cancer cells. Yeah, but we’re not, I there’s only one or two that have been approved around the world. So, but we’re sort of on the cusp of this happening. If this is a feasible strategy, then. Then presumably there’s a number of ways of doing it and there’ll have to be different viruses for different cancers.


HEFFNER: I mean, no offense by this, to the scientific community, but I feel like we’ve been hearing we’re on the cusp of this, for a while. And obviously in the COVID era, we’ve been told that, too, on the cusp of, you know, vaccinating to live freely and mobile, free of virus, or fear from virus. And that’s not really the case. But I feel like in the cancer space, prior to Covid’s emergence, that was one where we constantly have been hearing from Lori Glimcher and other people we’ve hosted, we’re on the cusp. Is this a different cusp or


MORGAN: (Laugh) Well of course it’s always hard to predict, especially the future. But, and we have had the War on Cancer in the 1970s. We had actually a War on Cancer going back into 1950s as well. I’m hopeful that we are on a slightly different era than we were. The power of recombinant technologies gives us a lot more tools than we had in the past. But I don’t, I don’t think, I’m not hopeful that we’ll get like a silver bullet that will, you know, cure all cancers. I’d rather see some cancers more amenable to this type of therapy than others. And so it will be sort of gradual treatments where we’ll slowly be getting better, better treatments, better survival rates. But to how long, how far away that is, it’s hard to say people, you know, like to say 10 or 20 years maybe, of course, as you say, that’s a sufficiently long period, so you won’t be able to track me down and say you were wrong (laugh) if it doesn’t pan out.


HEFFNER: You know, when, when you think of that characterization, is it fair? The characterization that I just offered about these periods that have, have given false hope?


MORGAN: Well, I think that perhaps, and perhaps years ago we underestimated how complex cancer was and how different different cancers are. So it’s not really one disease that we’re trying to attack, right? It’s a multitude of diseases.

HEFFNER: And that was perhaps the failure in behaving as though you could cure or treat it with a silver magic bullet. But in your book, you focus on this thesis, that tumor virology metamorphosized biomedicine. It, as a result of studying tumors, biomedicine has forever changed. And I wanted to give you an opportunity to expound on that point.


MORGAN: Right. Well, I think that our view of cancer today is, is, is informed directly from all this research. What viruses allowed us to do in the past was like isolate a small piece of DNA and see what it does when you inject it into a cell, because that’s what viruses basically do. So the contemporary view that I think basically any oncologist would give you is that you’ve got these important genes in the cell that are mutated in cancer cells. That comes from the study of tumor viruses because they either had oncogenes inserted into their own genomes, or they interacted with other proteins that are really important in turning a cell from a normal cell into a, into a cancer cell. Today it’s, if you’re at a very good cancer center, you can take, you can have your tumors sequence to see which, which genes have been mutated and then your therapy can be tailored to you to know which drugs are going to work best for you. I don’t think any of that would’ve happened without tumor virology. And so it’s sort of a, I think it’s a victory for what you might call reductionism in biology, because you’re looking at a very, very simple system. And once you understand that system, you then try and apply some of the lessons to more complicated systems like human cells.


HEFFNER: What’s your hope in terms of the reaction of the scientific community to your book and to the chronicling of that history? What’s your hope that they will glean from it?


MORGAN: Yeah. Well, I wrote the book in part because I thought that there’s a lot of interesting characters in this history. A lot of these scientists are interesting people in their own right. But I, I also wanted to counter what I see as sort of an anti-science sentiment emerging in our culture. And I think part of it is driven because most people don’t actually know scientists, right? The average person isn’t friends with biomedical scientists. They don’t know any of those people. So I thought that my book, which sort of focuses on the biographies of a number of these important scientists would give you a picture into what motivates these people, why they did, what they did, and sort of humanize the science in a way, right? So these people by and large, don’t have ulterior motives. They’re really just interested in learning how cells work and how viruses work, how they reproduce themselves. And it has this consequence that we can, through better understanding how our cells work direct our, our research enterprise towards more likely better drugs. So I’m hoping that knowing the history will help the average person, as well as people that work in oncology think more about trajectory of research. One of the themes that comes out is that big breakthroughs take a long time, right? So I’ve covered, I’m covering over a hundred years of research, and it was sort of the sustained focus for decades and decades before you get progress. I think in today’s world, we kind of want things to happen really, really quickly, but sometimes it just takes a long time. And, but we shouldn’t give up.


HEFFNER: I’m struck by your comments about the American people, not knowing scientists. And I don’t know if you meant that in a specific U.S. context or more broadly, folks in any country, in any part of the world, not…


MORGAN: Yeah, that’s probably more true more broadly. I think.


HEFFNER: And your point in telling the stories was to reveal the inner humanity and kind of shared values of scientists. And you clearly feel that there is a disconnect here. Is that something that predates the pandemic?


MORGAN: I think, I think I mean the anti-vaccine movement is a good example of this, right? I mean, it obviously got stronger during the pandemic. But there are a lot of people who just won’t accept mainstream advice, right? Or they think that anything coming out of a pharmaceutical company is corrupt because they are only in it to make money. I think that predates the pandemic. I think the pandemic’s kind of made it worse and it seems like it’s been politicized as well. So depending on your political leanings, you can kind of predict where some people, where some people will be on, you know, getting vaccinated against COVID. But a lot of the basic research that I cover is done by individual scientists who don’t aren’t in it for the money. Right? They’re not really in it, even in it for the fame, I don’t think. Of course they’re people like us, but they are just interested in understanding how nature works which is something we all kind of share perhaps in some level.


HEFFNER: Well, I would hope that your thesis is correct. But the stigma that is, rubs folks the wrong way, that is the ulterior motive, whether that’s financial or world domination, which financial is a piece of, is it born out of a, of a cynicism, of a conspiratorial outlet outlook? What to you is the, is the genesis of that? And, and is it fair to say that in, if you look at the global economy and our present capitalist system, that there is enough evidence of the ulterior motive, of the opposite of what you’re saying, being true, right?


MORGAN: Yeah. I mean, that’s a really tough question to answer, I think, but it seems to me some of it’s got to be driven by the fact that technology has got us into trouble with all sorts of things, right? Like technology brought us nuclear weapons and brought us microplastics and the ocean. A lot of health concerns maybe are driven by technology too. So there’s been a lot of cases of things where technology hasn’t been uniformly good for humans. But I think it’s a mistake to think that it’s uniformly bad, right? There’s going to be cases where technology does give us ways to extend our lives and improve them.


HEFFNER: And in the closing minute or two that we have, what is one story to you that can be a very purposeful and useful anecdote or account that shows the likeness of the scientists as one of us?


MORGAN: Okay. Let, let me tell you the story about Ludwik Gross. He was a Polish physician working just before the beginning of the Second War. He fled before the Nazis could catch him. He was Jewish and he fled to Poland and then he fled to the United States. And he was convinced actually that practically all cancers are caused by viruses. And he came to the United States. He signed up for the military. He was he became Captain Ludwik Gross. And while he was serving, he still ran experiments on mice. He was trying to work out if he could find viruses that caused cancer in mice. And he actually succeeded in doing this. But he had very little support. And at one point he was, he had a mouse colony inside the trunk of his car. And he was running experiments on the side, in the back of his car. And almost everybody thought he was misguided, right. That he was, he was a kook, at the time. But he succeeded. He, like persisted and he actually found two viruses. One that’s quite well known called polyoma virus that caused cancer. And so that was a turning point in the 1950s when after, after these discoveries and knew we could reproduce, we could reproduce cancers being caused in mice by this virus that he discovered, it became a legitimate field. So he’s sort of one of my heroes of the story. He was sort of seen as an underdog but persisted with this idea and was eventually vindicated.


HEFFNER: Well, Greg, I want to thank you for sharing the story of “Cancer Virus Hunters.” I urge our viewers to check out Gregory Morgan’s new book “Cancer Virus Hunters: A History of Tumor Virology.” Really appreciate your insight and perspective today. Greg.


MORGAN: Thank you very much for having me. I enjoyed it a lot.


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