Breaking Barriers in the Future of Brain Tumor Treatment
April 21, 2025ID13054
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- 00:00Funding for Yale Cancer Answers
- 00:02is provided by Smilow Cancer
- 00:04Hospital.
- 00:06Welcome to Yale Cancer Answers
- 00:08with the director of the
- 00:09Yale Cancer Center, doctor Eric
- 00:11Winer.
- 00:12Yale Cancer Answers features conversations
- 00:15with oncologists
- 00:16and specialists who are on
- 00:17the forefront of the battle
- 00:18to fight cancer.
- 00:20This week, it's a conversation
- 00:21about the care of patients
- 00:22with brain tumors with doctor
- 00:24James Hansen.
- 00:25Doctor Hansen is an associate
- 00:27professor of therapeutic radiology at
- 00:29the Yale School of Medicine.
- 00:31Here's doctor Winer.
- 00:33How did you get interested
- 00:34in radiation oncology?
- 00:37That goes back
- 00:39way back to when I
- 00:40was a kid growing up,
- 00:42and I was a big
- 00:43fan of Marvel comic books.
- 00:45And if anybody remembers those,
- 00:47all those superheroes got their
- 00:48powers from radiation. Spiderman
- 00:51was bitten by a
- 00:52radioactive spider.
- 00:53The Incredible Hulk was bombarded
- 00:55with gamma rays.
- 00:56I figured, who wouldn't want
- 00:58to have a career in
- 00:59radiation?
- 01:00So, unfortunately,
- 01:02I've been a radiation doctor
- 01:03for years now, and I'm
- 01:04here to tell you, those
- 01:05comics are actually fiction. I've
- 01:07not yet seen anybody
- 01:09exposed to radiation get superpowers.
- 01:11But I have witnessed some
- 01:13incredible courage in our patients.
- 01:15And I would say those
- 01:16are the real superheroes for
- 01:17sure.
- 01:18Why don't you tell us
- 01:19a little bit
- 01:20about
- 01:21gamma knife? What is this?
- 01:24It's a form of radiation.
- 01:26I think a lot of
- 01:26people know that, but they
- 01:28don't know much in the
- 01:29way of specifics and
- 01:31where we might use it
- 01:32and where we wouldn't use it.
- 01:35I absolutely
- 01:37love the Gamma Knife. I
- 01:38think it's a fantastic machine.
- 01:40I have just one
- 01:42problem with it, and that
- 01:43is its name. I wish
- 01:45for all the world it
- 01:46would not have included the
- 01:47word knife because that scares
- 01:49all of our patients. There
- 01:50is no knife involved. It's
- 01:52just a machine
- 01:53that is designed to give
- 01:54radiation
- 01:55extremely accurately and, specifically,
- 01:58extremely accurately in the brain.
- 02:00And when we're talking about
- 02:00the brain, accuracy is literally
- 02:03everything because we're using radiation
- 02:05to kill things, which is
- 02:06good for tumors, but not
- 02:08great for normal tissue cells.
- 02:10A gamma knife can get
- 02:11us to less than a
- 02:11tenth of a millimeter of
- 02:13error in our targeting.
- 02:14We can leave
- 02:15the rest of the normal
- 02:16brain alone.
- 02:17We do that with a
- 02:19combination of a 3D
- 02:20targeting box that goes on
- 02:21the patient's head,
- 02:22some complex MRI imaging, and
- 02:25then some very sophisticated arrangements
- 02:26of some actual
- 02:28radioactive sources that give a
- 02:30hundred and ninety two beams
- 02:31to one little tiny dot
- 02:32in space.
- 02:33And so we can position
- 02:34the patient so that one
- 02:35little dot is right where
- 02:37we want it. It's kinda
- 02:38like painting by pointillism, where
- 02:40you just dot dot dot
- 02:41dot dot to cover your
- 02:42target, and you leave the
- 02:43rest of the brain alone.
- 02:45We call those shots.
- 02:46So you can target very
- 02:49small tumors.
- 02:50The smaller, the
- 02:51better. We love small. Yes.
- 02:53And
- 02:54what's the largest tumor you
- 02:56can target with a gamma
- 02:57knife?
- 02:58There's no limit,
- 03:00but the larger the tumor,
- 03:02the greater the volume of
- 03:03normal brain around it that
- 03:05is getting hit by some
- 03:06degree of radiation. So we
- 03:07have to be a little
- 03:07bit careful. We've got ways
- 03:09that we can deal with
- 03:09that by adjusting our dose
- 03:11or maybe having the patient
- 03:12come back for a couple
- 03:13treatments instead of doing it
- 03:15all in one day. So
- 03:16there's no real limit,
- 03:17truthfully.
- 03:19But, practically, when
- 03:21would you stop thinking about
- 03:23doing gamma knife
- 03:24and start thinking about doing
- 03:25something different in terms of
- 03:27size?
- 03:28Well, it depends very much
- 03:30on
- 03:31what kind of a cancer
- 03:32we are dealing with, because
- 03:34as you know, it's an
- 03:35entirely new world now with
- 03:36targeted therapies and such.
- 03:38If
- 03:39we are worried that a
- 03:40cancer is spread widely throughout
- 03:42the brain, it's not just
- 03:43in the one area, then
- 03:45we'll need to have conversations
- 03:46about perhaps we might need
- 03:47to revert to the standard
- 03:49technique of the whole brain
- 03:50radiation.
- 03:52But we try to avoid
- 03:53that for as long as
- 03:54we can because we do
- 03:55have this gamma knife technology.
- 03:58And
- 03:58with this technology,
- 04:00you can give much higher
- 04:01doses of radiation than with
- 04:03standard radiation?
- 04:05That's basically true. Yeah. It's
- 04:07it comes down
- 04:08to the biology of radiation,
- 04:10and we didn't need to
- 04:10get too far into the
- 04:12woods on that. But there's
- 04:13a difference between giving radiation
- 04:15all in one big dose
- 04:17versus a bunch of small
- 04:18doses. And what the gamma
- 04:20knife can do, because it's
- 04:21so accurate,
- 04:22we can really hit the
- 04:23target hard
- 04:24once
- 04:25compared to having to treat
- 04:26the entire brain over multiple
- 04:28fractions with a tinier dose
- 04:29to let the brain recover.
- 04:31And when you do those
- 04:33multiple fractions, say over two
- 04:36weeks or even longer sometimes,
- 04:39the total dose has to
- 04:41be increased.
- 04:43It's
- 04:44a little bit of hand
- 04:45waving in terms of how we
- 04:48say which dose is equivalent
- 04:49to the other, and not
- 04:50all of us believe those
- 04:51equations.
- 04:52But theoretically, yes, we might
- 04:54treat in a single fraction,
- 04:55for example, to a dose
- 04:57of twenty gray,
- 04:58whereas the total dose of
- 04:59a whole brain treatment is
- 05:00typically
- 05:01thirty gray.
- 05:02But it's not a perfect
- 05:04correlation at all.
- 05:07And when you're treating cancer
- 05:09in the brain,
- 05:10this is both cancers that
- 05:12start in the brain as
- 05:13well as cancers that spread
- 05:15to the brain?
- 05:16That's right. It does
- 05:18depend very much on exactly
- 05:20what we are treating.
- 05:22By far and away, the
- 05:23most common
- 05:25tumors that we are treating
- 05:26are cancers that have spread
- 05:27to the brain, which are
- 05:28things that we call brain
- 05:29metastases.
- 05:30There are other forms of
- 05:31tumors that we treat as
- 05:32well that start in the
- 05:33brain, meningiomas,
- 05:35pituitary adenomas, and such.
- 05:37But far and away, the
- 05:38metastases are our number one
- 05:40that we treat.
- 05:42And
- 05:43metastases
- 05:43happen in patients who have
- 05:45an initial cancer
- 05:47and then develop a recurrence
- 05:49of that cancer. And sometimes
- 05:51it spreads to the brain.
- 05:53Recently, there's been talk that
- 05:55brain metastases seem to be
- 05:57increasing.
- 05:58Do you have thoughts about
- 05:59that?
- 06:01I think that's in large
- 06:03part credit to oncologists like
- 06:06yourself, that are getting better
- 06:08and better at treating disease
- 06:10everywhere else in the body.
- 06:12The brain, unfortunately,
- 06:14is a little bit tougher
- 06:15to get those medicines into.
- 06:17As we know, there's
- 06:18something called the blood brain
- 06:19barrier that keeps those drugs
- 06:20out. So while we're doing
- 06:22better at controlling disease outside
- 06:23the brain,
- 06:25we still need better ways
- 06:26to control disease in the
- 06:27brain. And that's getting
- 06:28better and better. So we're
- 06:31relying less and less on
- 06:32the whole brain radiation,
- 06:34more on the gamma knife
- 06:35as these better targeted therapies
- 06:36come along to help us.
- 06:39And there have been studies
- 06:40that have shown that
- 06:42patients actually do better when
- 06:43treated with gamma knife
- 06:45or related technologies
- 06:47than getting whole brain.
- 06:50Sure. Absolutely. The normal
- 06:53brain doesn't wanna get exposed
- 06:54to that radiation. It can
- 06:55have an effect on things
- 06:56like
- 06:57short term memory and
- 06:59just overall
- 07:00energy levels. So if we
- 07:02can avoid it, we should
- 07:03when we can. That's not
- 07:05to say that there isn't
- 07:06a time and a place
- 07:07for the whole brain radiation.
- 07:09It's we just have to
- 07:10pick and choose our battles,
- 07:11for sure.
- 07:12And
- 07:13when would you give whole
- 07:14brain radiation?
- 07:16So
- 07:17it's very much dependent on
- 07:18the patient and the situation.
- 07:21If we don't have
- 07:22a good targeted therapy to
- 07:23back us up and we
- 07:25have
- 07:26many, many spots to go
- 07:27after, you know, thirty, forty,
- 07:29fifty,
- 07:30then we know if we
- 07:31see fifty spots, there's probably
- 07:33another ten or twenty that
- 07:34we can't see, and it
- 07:35makes more sense for the
- 07:36patient
- 07:37to treat everything.
- 07:39Other types of disease, for
- 07:40example, small cell lung cancer
- 07:42is a type that tends
- 07:44to very commonly go to
- 07:45the brain, and we tend
- 07:46to have a lower threshold
- 07:47for activating that whole brain
- 07:49decision in that case. But
- 07:50even that, we're trying to
- 07:51back off on nowadays.
- 07:55I have to say as
- 07:56a medical oncologist
- 07:59taking care of mostly women
- 08:01with breast cancer,
- 08:04that the advances in radiation
- 08:06largely through techniques like the
- 08:08gamma knife, have been incredible
- 08:09over the years.
- 08:10And
- 08:12radiation oncologists have been able
- 08:14to treat
- 08:16more and more with
- 08:18really less and less toxic
- 08:19approaches.
- 08:21Yeah. And I'm particularly excited
- 08:23about what we're seeing with
- 08:24these new antibody drug conjugates
- 08:27like HER2 that are really
- 08:29helping us delay that need
- 08:31to activate the whole brain
- 08:32protocol. So we can help
- 08:34you
- 08:35target just the most important
- 08:36tumors, and the drugs can
- 08:38perhaps take care of the
- 08:38smaller ones, which is a
- 08:40big change from
- 08:42even just a few years
- 08:43ago.
- 08:44Yeah. Which is,
- 08:46of course, among the many
- 08:48reasons why having
- 08:50people participate in multidisciplinary
- 08:52teams is so important.
- 08:54Absolutely.
- 08:56We wouldn't have nowhere near
- 08:57the confidence to do what
- 08:58we do if we didn't
- 09:00know we had the backup
- 09:01of people like Veronica Chiang,
- 09:03who's one of our neurosurgeons,
- 09:04who can operate when we
- 09:06need help or operate the
- 09:08the laser technology when there's
- 09:09some radiation treatment effect that
- 09:10we need to fix.
- 09:13I always need someone to
- 09:14call when I say, you
- 09:16know, I'm this is close
- 09:17to needing whole brain, but
- 09:18can you back me up?
- 09:19Do you have any targeted
- 09:20therapy that I can argue
- 09:22will take care of the
- 09:22smaller spots, and I can
- 09:23just go after the
- 09:24important ones right now?
- 09:26You can't do this
- 09:28by any one specialty anymore.
- 09:30Not sure maybe you ever
- 09:31could, truthfully.
- 09:33It's absolutely the case.
- 09:35And what about
- 09:37patients who have primary brain
- 09:39tumors where
- 09:41the cancer starts in the
- 09:42brain? Cancers like glioblastoma
- 09:45and other forms of
- 09:47brain cancer?
- 09:48Are there times when you
- 09:49use Gamma Knife after someone
- 09:51has had surgery?
- 09:53Very rare,
- 09:54especially here in our own
- 09:56institution.
- 09:57For example, the
- 09:58glioblastomas,
- 09:59we tend to think
- 10:01because of their infiltrative nature
- 10:03and the larger volume that
- 10:05you need to cover to
- 10:06get all
- 10:07the hands of the cells
- 10:08that are extending,
- 10:09it's better to go with
- 10:11that longer, what we call
- 10:12fractionated course and in combination
- 10:14with the chemotherapy.
- 10:16The Gamma Knife for other
- 10:18radiosurgery techniques might come into
- 10:20play
- 10:21after that. So if later
- 10:22down the road there was
- 10:23just one little spot that
- 10:25came back, then I might
- 10:26get a call from, for
- 10:27example, doctor Contessa or doctor
- 10:29Bindra to say,
- 10:30do you think you
- 10:31could gamma knife that one
- 10:32little spot? I've already given
- 10:33what I can do from
- 10:34the Linac side, which is
- 10:35called a linear accelerator, the
- 10:36normal radiation.
- 10:38It's a fairly
- 10:39rare occurrence that we would
- 10:40do that.
- 10:42Yeah.
- 10:45I think that,
- 10:47you know, all of this
- 10:48shows that these decisions
- 10:50are really very, very complicated.
- 10:53And then what about other
- 10:55cancers in other parts of
- 10:57the body other than the
- 10:58brain? Do you use gamma
- 11:00knife in those situations too?
- 11:02Not the gamma knife. The
- 11:04gamma knife is specifically
- 11:05built around that head
- 11:07frame and such so that
- 11:08we can have a 3D
- 11:09targeting specifically
- 11:11in the brain. But the
- 11:13concept
- 11:13of radiosurgery,
- 11:15meaning giving radiation
- 11:17extremely accurately in one dose
- 11:19or a couple of
- 11:20doses,
- 11:21absolutely applies elsewhere in the
- 11:23body.
- 11:24We just call it something
- 11:25else. We call it stereotactic
- 11:27body radiotherapy,
- 11:29or SBRT.
- 11:30For example,
- 11:32doctor Johung tends to use
- 11:33this for our pancreatic cancers.
- 11:35Doctor Park uses this for
- 11:36our lung cancers.
- 11:38Absolutely, the field of radiation
- 11:40has exploded in terms
- 11:42of new,
- 11:43faster, better ways to use
- 11:44radiation to treat cancer. And
- 11:46so what is it that
- 11:47led to this bifurcation
- 11:48between Gamma Knife and stereotactic
- 11:52radiosurgery?
- 11:54Well, the concept of stereotactic
- 11:56radiosurgery just means we're treating
- 11:58something super accurately with a
- 12:00high dose in a few
- 12:01fractions.
- 12:03The gamma knife is entirely
- 12:04based on basically a brand
- 12:07and the use of that
- 12:07specific head frame. So you
- 12:09may have heard of things
- 12:10like the CyberKnife.
- 12:12Again, they decided to use
- 12:14the word knife. I think
- 12:15that was a mistake.
- 12:17So that's just
- 12:18a different brand?
- 12:20Yeah. It does not use the
- 12:23cobalt sources like the
- 12:24gamma knife does, but it's
- 12:25the same idea of giving
- 12:26radiation hyper accurately just to
- 12:29the problem areas.
- 12:30And
- 12:31just back to gamma knife
- 12:33for a second. So a
- 12:34a patient has a gamma
- 12:36knife treatment.
- 12:37Do they need to be
- 12:38in the hospital? Can they
- 12:39go home that same day?
- 12:41What are the
- 12:42consequences a day or two
- 12:44later?
- 12:45It's remarkably well tolerated.
- 12:47Almost all of our patients
- 12:48go home the very same
- 12:49day.
- 12:51They're a little tired for
- 12:52a couple days and a
- 12:53little sore where the frame
- 12:54has been attached.
- 12:56But other than that, it's
- 12:57a very well tolerated treatment.
- 12:58And that is a huge
- 12:59benefit
- 13:00because it's so much faster
- 13:01than other forms of radiation.
- 13:03We can get them on
- 13:04to the next phase of
- 13:05either chemotherapy
- 13:06or targeted therapy or clinical
- 13:08trial without any delay.
- 13:12Even beyond that, who wants
- 13:14to feel badly from a
- 13:15treatment? The
- 13:17easier a treatment
- 13:18is, the more you can
- 13:20think about getting it.
- 13:23Well, we're gonna take a
- 13:25very brief break. And when
- 13:27we come back, we'll continue
- 13:29talking to
- 13:30James Hansen, associate professor of
- 13:32therapeutic radiology,
- 13:34and we'll move on to
- 13:36talk about
- 13:37some of his own research,
- 13:39focused on a very different
- 13:41area.
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- 14:00Genetic testing can be useful
- 14:02for people with certain types
- 14:03of cancer that seem to
- 14:04run-in their families.
- 14:05Genetic counseling is a process
- 14:07that includes collecting a detailed
- 14:09personal and family history,
- 14:11a risk assessment,
- 14:12and a discussion of genetic
- 14:14testing options.
- 14:15Only about five to ten
- 14:17percent of all cancers are
- 14:18inherited and genetic testing is
- 14:20not recommended for everyone.
- 14:22Individuals who have a personal
- 14:24and or family history that
- 14:25includes cancer at unusually early
- 14:28ages,
- 14:29multiple relatives on the same
- 14:30side of the family with
- 14:32the same cancer,
- 14:33more than one diagnosis of
- 14:35cancer in the same individual,
- 14:37rare cancers,
- 14:38or family history of a
- 14:40known altered cancer predisposing
- 14:42gene could be candidates for
- 14:43genetic testing.
- 14:45Resources for genetic counseling and
- 14:47testing are available at federally
- 14:49designated comprehensive cancer centers,
- 14:51such as Yale Cancer Center
- 14:53and Smilow Cancer Hospital.
- 14:55More information is available at
- 14:57yale cancer center dot org.
- 14:59You're listening to Connecticut Public
- 15:00Radio.
- 15:02Hello again. This is Eric
- 15:04Winer with Yale Cancer Answers,
- 15:06and I'm here again
- 15:08with our guest, doctor James
- 15:10Hansen,
- 15:11a radiation oncologist
- 15:13who focuses on
- 15:15gamma knife treatment
- 15:16in his clinical work.
- 15:18But beyond that, like many,
- 15:21many physicians,
- 15:23is involved in research as
- 15:25well,
- 15:26involved in research to try
- 15:29to make
- 15:30treatment better for patients in
- 15:32the future.
- 15:33Some of that research involves
- 15:34clinical trials. Some of it
- 15:36involves more basic work to
- 15:38try to
- 15:39come up
- 15:40with new approaches
- 15:43that could lead to clinical
- 15:45trials in the future.
- 15:47So I wanna talk to
- 15:48you about
- 15:50lupus related antibodies
- 15:52and how this might
- 15:55ultimately improve
- 15:56care for individuals who have
- 15:58glioblastoma.
- 15:59And maybe before you talk
- 16:02about lupus related antibodies,
- 16:04maybe you could just talk
- 16:05for
- 16:07a minute or two about
- 16:08glioblastoma
- 16:10and
- 16:11where we stand with that
- 16:12very difficult to treat cancer.
- 16:15Did you say you wanted
- 16:16me to talk about lupus
- 16:17related antibodies in cancer?
- 16:19That sounds a little off
- 16:20the norm here.
- 16:24It is, it's your work.
- 16:25Oh, how about that?
- 16:26Alright. Yes. Happy to talk
- 16:28about that.
- 16:29So
- 16:30glioblastoma
- 16:31is one of the most
- 16:32aggressive
- 16:33primary brain tumors that we
- 16:35encounter.
- 16:36And one of the reasons
- 16:38that it's so tough to
- 16:38beat is
- 16:40that it has figured out
- 16:41ways to sort of cloak
- 16:43itself so that it kind
- 16:44of, I like to say, it runs
- 16:46silent, meaning that our own
- 16:48immune system can't see it,
- 16:50can't fight it off. So
- 16:51we try to be
- 16:52aggressive with surgery and radiation
- 16:54and chemotherapy, but we really
- 16:56need backup from the immune
- 16:58system to get after it.
- 16:59And, unfortunately,
- 17:00the T cells and such
- 17:02just don't tend to find
- 17:03it. And that's why glioblastoma
- 17:05is called immunologically,
- 17:07quote, unquote,
- 17:08cold.
- 17:10So we figured
- 17:11if there was a way
- 17:12to heat up those tumors,
- 17:13maybe we could get better
- 17:14outcomes.
- 17:15And by cold, you mean
- 17:16that
- 17:18immunotherapy
- 17:19as we give it today
- 17:20doesn't seem to have any
- 17:22impact on glioblastomas.
- 17:23You got it. So all
- 17:24those antibody things we see
- 17:26advertised on TV that are
- 17:28really making a huge difference
- 17:29in other kinds of cancers,
- 17:31they're not touching glioblastoma.
- 17:33So we need a way
- 17:34to figure out why
- 17:35or how to break that
- 17:37cycle.
- 17:38So where would we
- 17:39look to find a hyperactive
- 17:41immune system?
- 17:43How about autoimmunity,
- 17:45like lupus?
- 17:47So in lupus,
- 17:49a patient's own immune system
- 17:50goes a little crazy and
- 17:52starts attacking its own cells
- 17:54and tissues.
- 17:56So we figured, well, if
- 17:57we could figure out what
- 17:58are the mechanisms
- 17:59driving that
- 18:01and just isolate a few
- 18:02of them, maybe we could
- 18:03use some of those
- 18:04to awaken the immune system
- 18:05in glioblastoma.
- 18:08And that's what my lab
- 18:09focuses on, is understanding mechanisms
- 18:11of autoimmunity
- 18:12with the goal of using
- 18:13them against cancer.
- 18:15And let me just ask
- 18:16you. Lupus, if I remember
- 18:18right, from
- 18:19days when I
- 18:21trained in internal medicine,
- 18:23is actually a disease that
- 18:24occasionally affects the brain as well?
- 18:26Absolutely. And patients,
- 18:29at times, unfortunately, get what's
- 18:31called lupus cerebritis,
- 18:34where those antibodies seem
- 18:36to attack the brain.
- 18:38That's exactly right.
- 18:40But how in the world
- 18:41are they doing that? Antibodies
- 18:43aren't supposed to be able
- 18:44to cross the blood brain
- 18:45barrier.
- 18:47Antibodies aren't even supposed to
- 18:48be able to penetrate
- 18:49into live cells. So that's
- 18:51a good segue. Thank you.
- 18:54Antibody therapy, as we know
- 18:56it currently, is focused on
- 18:58binding things
- 18:59on the outside of cells,
- 19:01things circulating in the blood
- 19:02or on the surface of
- 19:03cells.
- 19:04Now this is where a
- 19:05lot of critics might say,
- 19:07well, no. Some antibodies get
- 19:08eaten by cells.
- 19:10But I say that those
- 19:11don't count because they then
- 19:12get destroyed inside the cell
- 19:13by endosomes and lysosomes.
- 19:16What's remarkable
- 19:17about lupus antibodies we have
- 19:19found
- 19:20is that a subset of
- 19:21them
- 19:22are reactive against a patient's
- 19:23own DNA.
- 19:25And so sort of a
- 19:26hallmark of lupus is these
- 19:27anti DNA antibodies.
- 19:30And so they look for
- 19:31DNA, and they find DNA
- 19:34where it is
- 19:35concentrated. So it's kind of
- 19:36like
- 19:38if anybody who's listening has
- 19:39seen the movie Star Trek
- 19:40there is a part
- 19:42of that movie wherein
- 19:43the Enterprise is facing a
- 19:45cloaked
- 19:46bad guy ship, and they
- 19:47can't figure out how to
- 19:48find it. Until suddenly, they
- 19:50realize
- 19:51the thing has to have
- 19:52a tailpipe. And so they
- 19:53figure out a way to
- 19:54fire off a photon torpedo
- 19:56to track its exhaust back
- 19:58to its source.
- 19:59Tumor exhaust is DNA,
- 20:02nucleic acids, as the tumor
- 20:03cells are cycling and releasing
- 20:05them. So we thought, well,
- 20:06maybe these anti DNA antibodies
- 20:07will find tumors by tracking
- 20:09their exhaust back to the
- 20:10source. And, indeed, they do.
- 20:12And what's even more remarkable
- 20:13is when they get there,
- 20:15they're sticking to the nucleoside
- 20:16components of DNA,
- 20:18and then the live tumor
- 20:19cells and other environmental
- 20:21cells
- 20:22are pulling those nucleosides in
- 20:25through this thing called a
- 20:26nucleoside salvage pathway.
- 20:28And so it pulls the
- 20:29antibody in. And the antibody
- 20:31then gets into those cells,
- 20:32skips all the security guys.
- 20:34It skips the lysosomes and
- 20:36the endosomes, and it has
- 20:37free rein inside that cell.
- 20:39Some of them go to
- 20:40the nucleus.
- 20:41Some go to the cytoplasm.
- 20:44What we just found, and
- 20:45we just published in Science
- 20:46Signaling and is getting quite
- 20:47a lot of attention and
- 20:48very excited about,
- 20:50is that one of these
- 20:51antibodies, when it gets into
- 20:53that cytoplasm, the liquid part
- 20:54of the cell, not the
- 20:55nucleus,
- 20:57it's sticking to RNA,
- 20:58a specific type of nucleic
- 21:00acid.
- 21:01And then finally,
- 21:02something inside the cell called
- 21:04a pattern recognition receptor
- 21:06sees that and says,
- 21:08that's not supposed to be
- 21:10here. I don't know what's
- 21:11going on, but something bad
- 21:13has happened. And it triggers
- 21:14off an immune reaction. And
- 21:16it finally says, oh my
- 21:18goodness.
- 21:19There's a tumor here this
- 21:20whole time. We've been sitting
- 21:21amongst this. We didn't realize.
- 21:23And then it recruits T
- 21:24cells, and we do see
- 21:25an improved response.
- 21:27So we figured out a
- 21:28way, we believe, to use
- 21:29a lupus antibody that can
- 21:31cross the blood brain barrier,
- 21:33penetrate into live cells, and
- 21:35tumor cells and non tumor
- 21:36cells fire up the immune
- 21:38system
- 21:39and improve outcomes. It does
- 21:40it by itself.
- 21:41And if you throw in
- 21:42an immune checkpoint blockade antibody,
- 21:44like those classic anti PD
- 21:46ones,
- 21:47it works even better. So
- 21:48we're pretty thrilled by
- 21:50this, and we we hope
- 21:51that we can get this
- 21:52to the clinical trials as
- 21:53soon as we possibly can.
- 21:55Now if it
- 21:57also goes to normal cells
- 21:59in the brain, is there
- 22:01some chance it would
- 22:03increase the
- 22:04side effects from immunotherapy
- 22:06in those normal cells in
- 22:07the brain?
- 22:09That's the real trick. Right?
- 22:10Is doing this in a
- 22:11way that we don't cause
- 22:12harm.
- 22:13And this is where it's
- 22:14all about
- 22:16where is the antibody gonna
- 22:17go. And and the beauty
- 22:18of this, and I wish
- 22:20I could take credit for
- 22:20it. I didn't design this.
- 22:22This is a natural antibody,
- 22:23a natural lupus antibody.
- 22:26It will only penetrate cells
- 22:28in areas that are super
- 22:30highly concentrated
- 22:31in the DNA that's released
- 22:33by the tumor because that's
- 22:35its path into the cell.
- 22:36So when it if it
- 22:37finds other areas in the
- 22:38normal brain that are not
- 22:40soaked in DNA, it will
- 22:41not penetrate. And that's the
- 22:43first thing that we looked
- 22:44for. Where does the
- 22:45antibody go? And it just
- 22:46goes into the area of
- 22:47the tumor and the surrounding
- 22:48area, not into the normal
- 22:50brain.
- 22:51So it preferentially
- 22:53goes into the tumor on its own.
- 22:54Correct. Based on
- 22:57targeting
- 22:58the DNA. And if you
- 23:00follow that reasoning further
- 23:02in noncancer applications,
- 23:05these antibodies will also find
- 23:06areas of damage. So for
- 23:08example,
- 23:09my colleagues and my
- 23:11team have found as well,
- 23:13these antibodies will find areas
- 23:14of a stroke
- 23:15in the brain
- 23:16or a heart attack
- 23:18Because DNA is being released
- 23:20by the damaged cells.
- 23:21Exactly.
- 23:23So all this excitement about
- 23:24this antibody by itself as
- 23:27engaging the immune system,
- 23:28I think, is great.
- 23:30There's one more dimension to it.
- 23:33Wait a second. If this
- 23:34antibody can get into cells
- 23:35and it can avoid all
- 23:37the security,
- 23:38skip the lysosomes,
- 23:40will it carry other things
- 23:42with it in?
- 23:43And indeed,
- 23:44we haven't published this yet,
- 23:45but I mean, this
- 23:46is just between you and me, right?
- 23:47No one's listening
- 23:48to this. I hope, oh,
- 23:48wait. There's this radio.
- 23:50I'll still be able to
- 23:51say it.
- 23:53Absolutely. These antibodies can carry
- 23:55cargos in with them, whether
- 23:57they are nucleic acids or
- 23:58linked other antibodies.
- 24:00So we can use these
- 24:01antibodies to deliver things to
- 24:02either increase the effect on
- 24:04tumors or perhaps to treat
- 24:06heart attacks, perhaps to improve
- 24:08improve treatment of stroke. The
- 24:09sky's the limit in my
- 24:11opinion.
- 24:12So
- 24:14almost like what we now
- 24:16call drug antibody conjugates, you
- 24:18could
- 24:19theoretically link
- 24:21a little bit of some
- 24:22drug that would be toxic
- 24:23to the cancer to the
- 24:25antibody.
- 24:27Absolutely. In fact, that was
- 24:29a paper from
- 24:30last year, and I'm
- 24:31really, really glad you gave
- 24:32me that segue.
- 24:34I was in, ACS Central
- 24:36Science. So everyone has asked
- 24:38me along the way,
- 24:39why don't you use these
- 24:40antibodies to deliver
- 24:42drugs? And I said, well,
- 24:43it doesn't make sense because
- 24:45the whole idea of an
- 24:46antibody drug conjugate
- 24:48is it gets eaten up,
- 24:49and then the lysosome
- 24:51breaks it down, and that's
- 24:51how the drug gets released.
- 24:53What's gonna release the drug
- 24:55for these antibodies? They don't
- 24:56go to the lysosome.
- 24:57But finally,
- 24:59a great postdoc by the
- 25:00name of Faye Kao in
- 25:01my lab figured out when
- 25:03one of these antibodies goes
- 25:04zipping on into the cell,
- 25:06this one goes into the
- 25:07nucleus,
- 25:09something happens and it triggers
- 25:10a specific
- 25:12protease,
- 25:13a protein that cuts
- 25:14other things apart from a
- 25:16lysosome
- 25:17to chase it into the
- 25:18nucleus.
- 25:19And that's what breaks it
- 25:20down in the nucleus. And
- 25:21then we realized,
- 25:23if we use a linker
- 25:25that that protease will cut,
- 25:27now we can deliver things
- 25:28into the nucleus,
- 25:29and the drug will be
- 25:30released. And so you've heard
- 25:32of ADCs,
- 25:33antibody drug conjugates.
- 25:35We have now coined the
- 25:36phrase
- 25:37ANADCs
- 25:38for anti nuclear antibody drug
- 25:41conjugates. And I'm really trying
- 25:42to get that to stick.
- 25:43So, hopefully, people that are
- 25:44listening will use that too.
- 25:46Well, I mean, of course,
- 25:48we're gonna have to see
- 25:49if this works in people,
- 25:50but,
- 25:51the whole idea sounds pretty
- 25:53cool to me.
- 25:55I think so too.
- 25:58And so
- 25:59in using these
- 26:00lupus antibodies, is there any
- 26:02risk that a patient
- 26:04is gonna develop some symptoms
- 26:06of lupus?
- 26:07Sure. That's the first question
- 26:09on our minds and on
- 26:10everybody's mind.
- 26:12When it comes to an
- 26:13anti DNA antibody,
- 26:15one of the dangers we've
- 26:16seen associated with lupus is
- 26:18that they can get stuck
- 26:19in the kidneys, and then
- 26:20they can trigger an immune
- 26:21response against the kidney to
- 26:23cause this thing called
- 26:24lupus nephritis, just inflammation
- 26:27of the kidney.
- 26:28The good news is
- 26:29most of that is caused
- 26:30by what we call the
- 26:32constant regions of the antibody,
- 26:34the FC tail for
- 26:35those that know any antibody
- 26:36structure.
- 26:38And the magic of these
- 26:39antibodies that allows them to
- 26:40do their thing to bind
- 26:42DNA, bind RNA,
- 26:44penetrate
- 26:45cells, has nothing to do
- 26:46with the FC or any
- 26:47of their constants, all in
- 26:48the variable regions. So we've
- 26:50created what we call fragments,
- 26:52single chain variable fragments and
- 26:54such that don't have any
- 26:56of the dangerous lupus causing
- 26:57parts, but still preserve the
- 26:59cell penetrating activity,
- 27:00the delivery aspects,
- 27:02and the engagement of all
- 27:03those factors that we want
- 27:04to try to fight off
- 27:05these diseases.
- 27:07Well, it sounds to me
- 27:07like we wanna try to
- 27:08encourage you to do this
- 27:09work as quickly as you
- 27:11can because it sounds pretty
- 27:13promising.
- 27:14Thank you. Yeah.
- 27:15I can take all the
- 27:16encouragement I can get.
- 27:22The truth is
- 27:23that if we didn't have
- 27:25research, if we didn't have
- 27:26both
- 27:27research in laboratories
- 27:29and research in the clinic,
- 27:31cancer treatment wouldn't change. And
- 27:34what has led to really
- 27:35a revolution in cancer therapeutics
- 27:38over the last
- 27:39twenty,
- 27:40twenty five years
- 27:42has been all the research
- 27:43that has gone on, and
- 27:44it's really quite remarkable.
- 27:47No question.
- 27:49You know, and it's just
- 27:51so very important.
- 27:52So in our last
- 27:54minute or so,
- 27:56maybe you could,
- 27:58look into the future
- 28:00and tell us what you
- 28:02think are gonna be the
- 28:04new directions for radiation oncology
- 28:07in the years ahead.
- 28:10Yeah. So I I'm very
- 28:11excited about
- 28:13immunotherapy
- 28:14and the combination
- 28:15with radiation.
- 28:17And we have so much
- 28:18to learn about
- 28:20how the radiation
- 28:22triggers and talks to the
- 28:23immune system.
- 28:24But when we can figure
- 28:25that out, I think we'll
- 28:26have even more ways to
- 28:28activate
- 28:29those, quote, unquote, cold tumors
- 28:31by giving radiation to the
- 28:32right area at the right time.
- 28:33Doctor James Hansen is
- 28:35an associate professor of therapeutic
- 28:37radiology at the Yale School
- 28:39of Medicine.
- 28:40If you have questions, the
- 28:42address is canceranswersyale
- 28:43dot edu,
- 28:45and past editions of the
- 28:46program are available in audio
- 28:48and written form at yale
- 28:49cancer center dot org.
- 28:51We hope you'll join us
- 28:52next time to learn more
- 28:53about the fight against cancer.
- 28:55Funding for Yale Cancer Answers
- 28:57is provided by Smilow Cancer
- 28:59Hospital.