Paul Calabresi, MD Memorial Lectureship: Lymphocytes as a 'Living Drug' for the Treatment of Cancer

May 31, 2023

Yale Cancer Center Grand Rounds | May 30, 2023

Presented by: Dr. Steven Rosenberg

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ID: 9986
To Cite: DCA Citation Guide

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00:00On behalf of myself and Doctor Weiner and
00:04the the team here at Yale Cancer Center,
00:07it's really my honor to introduce our
00:0915th Calabresi Memorial Lecture and I
00:12think I've been here for about 12 of
00:15them in honor of Doctor Paul Calabresi.
00:18We always are proud to welcome the Calabresi
00:21family with us in person or online.
00:25We have actually in the front
00:27row Judge Guido Calbresi,
00:29and I'll have him say a few words at
00:32some point and just received a week ago
00:34with the honor and another Yale degree.
00:37He's already had several and you
00:40know Paul's younger brother and I've
00:42been very fortunate to know Guido
00:43for a long time as well.
00:44We also have Steven Calabresi on his way
00:48from Rhode Island and we have several
00:50other Calbresi family online and we're
00:52really honored to have Steven Rosenberg.
00:55This year's Cal Brazi lecturer and
00:57we've been Vince and I have been
00:59trying to get Steven for years and the
01:02offer of doing it virtually was fine
01:04because that this is such timely work.
01:06It's the type of work that we
01:08want to build here at Yale.
01:10We actually have Mario Snow here who's
01:12will show up at some point, Steve.
01:13So we're really happy you're here.
01:15But let me say a few words about Paul.
01:18Paul Cal Brazi is often referred
01:20to as the father of oncology
01:22and as influence here at Yale.
01:24Remains to this day.
01:25He's a former faculty member
01:27of Yale School of Medicine.
01:29In fact,
01:30he I believe he held one of the jobs I hold.
01:32He built medical oncology at a time when I
01:34don't think it really was medical oncology.
01:36So he really, he really built the field.
01:39He was internationally recognized for
01:41the pharmacology of anti cancer agents.
01:44And if you walk through the B wing,
01:45you still feel his influence,
01:47the people he worked with,
01:47the people he recruited.
01:49And he also serves as the director of
01:51Yale Cancer Centers Advisory Board.
01:53Until 2003.
01:56Unfortunately,
01:56he himself passed away from cancer,
01:59showing us how while we're making progress,
02:02we still have so much more we need to do.
02:05I have a good fortune to meet Paul.
02:07I hate to say it, 43 years ago.
02:09I don't think I'll talk about
02:11that too much here.
02:12But his son Peter was my
02:14freshman roommate at Yale,
02:16and I met Peter and.
02:18What better for someone who wanted
02:19to be a doctor to have as a roommate,
02:21you know, the father of oncology.
02:23It was very nice.
02:24They didn't like me at first too much.
02:26But I've the family has warmed up to
02:27me over the years and actually I've I I
02:30was looking through some photos last night.
02:32You know it was an error without iPhone,
02:33so it's hard to find photos like it is now.
02:35But I've spent many memorable times
02:37with the Cal Brazi family over the
02:40Yale Paul was an advisor, a mentor,
02:43and a really good friend to me.
02:46Actually Vince and I, I still we know we
02:48we helped him with his disease as well.
02:50And having this job here means so much to me.
02:53One of the reasons I I'm back at
02:55Yale is Paul had always told me
02:57Yale is a great place for you.
02:59I think you'd be happy there.
03:01So joining us today we have Guido Calbresi
03:04as I mentioned Doctor Calgary's brother,
03:06his wife Anne I believe is online.
03:08I talked about Steven, Paul's son.
03:11His wife Mimi and Paul's daughter
03:13Janice and son Peter are online.
03:16So this is a very special grand rounds.
03:19We have a plaque for you, Steve.
03:22I don't know if it arrived yet.
03:23It has to get to NCI security.
03:25But what I'm going to do now is I'm
03:27going to turn it over to Vince De Vita
03:28who needs a little introduction here,
03:30but certainly another father of oncology
03:33and actually Paul's good friend.
03:35And I'm going to let Vince come up,
03:37introduce the you Steven,
03:38and then we'll do a quick photo
03:39with you in the background.
03:41We'll figure out how to do a
03:42hybrid photo and then we'll give
03:43the time to you for your talk.
03:45Vince.
03:58Yeah, My welcome to the Calabresi family.
04:01It's always a pleasure to see
04:03you here and reminisce about my
04:06old friend and my mentor, Paul.
04:08I'm sure he's up there looking
04:10down saying this is great.
04:14And it's a real pleasure to
04:16introduce my longtime friend
04:17and colleague Steve Rosenberg.
04:19I met Steve in 1974 when
04:23he arrived fully formed.
04:25As the new chief of the surgery brands
04:27right out of his training program,
04:29this caused quite a stir because
04:32the old administration of surgeons
04:35were oldfashioned and their motto
04:37was if you can't go wide, go deep.
04:39And and Steve was a thinking surgeon,
04:42which immediately changed the
04:44ability to collaborate and to
04:46consult with the surgery department.
04:47It was a fun time for the he also came
04:52with his passion for immunotherapy.
04:54And in the book he was to write a
04:59lot later he describes the the source
05:02of his passion in immunotherapy.
05:04It was a patient he operated on in 1968
05:07who came in with right up a quadrant pain,
05:10had a non visualizing gallbladder,
05:12was all set to go to operation.
05:14And Steve reviewed his old charts and he had
05:17come in 12 years earlier with belly pain.
05:20He was operated on a big masses of
05:22tumor with metastasis to the liver.
05:25And here he was 12 years
05:26later he was supposed to die.
05:27Few months later he was 12
05:29years later he was fine.
05:30Steve thought this was a powerful expression
05:33of the immunotherapy and he wanted to
05:36find out how we could harness this
05:38work. And since then, with
05:42fierce intensity, he has worked in
05:45the immunotherapy field and he has
05:49unwavering focus and stayed on this.
05:52Doing work in vitro and then in
05:54animals and then repeating the animal
05:56studies in humans to the point where
05:58he's become the lead investigator
06:00in the world in immunotherapy,
06:03having either discovered or developed
06:05all of the things that have been
06:08done in immunotherapy that are now
06:10making us very excited in the clinic.
06:13And since we're talking about
06:15fathers of programs,
06:16I would sort of view Steve as the
06:18father of the immunotherapy of cancer.
06:21He got his bachelor's degree and
06:24his MD degree from Johns Hopkins.
06:26He's got his PhD from biophysics
06:29from Harvard,
06:31and he spent his time in Boston at the
06:33Peter Ben Brigham getting a surgical
06:36training under the famous Brandy Moore.
06:38And then during that time he'd spent two
06:41years coming to the clinical associate
06:43at the National Cancer Institute.
06:45I also started as a clinical associate.
06:47We used to refer to ourselves
06:49as the Yellow Berets.
06:51Because it was a Vietnam War
06:53and we got our military credit
06:56without any of the gunfire.
06:59Steve may forgive me for not
07:01going over his honors and awards.
07:03They're just too many.
07:05I stopped counting 80.
07:08And finally,
07:09I've been working with Steve on
07:11the textbook answer Principles of
07:13Practice of Oncology for 42 years.
07:16He and I are two of the three editors,
07:19and it has been quite an experience.
07:21The reason the book has risen to the
07:24most popular Kansas text in the world is
07:27of the fierce competitiveness amongst
07:30the editors in preparing the book,
07:33making sure that we each,
07:35the other guy,
07:36was doing all the things he had to do.
07:38And of all the editors,
07:40Steve was the most competitive and not
07:43just a little story about to illustrate that.
07:46The publishers took us away,
07:49reached new addition a one week
07:52before to set the table of contents
07:55and pick the authors and invite
07:57them and at the end the second week.
07:59And so we work very hard during those days,
08:02getting up at 7:00 in the morning
08:04work until five and at the end
08:06of the day we would, you know,
08:08do our exercise and relax.
08:10And Sam Helman,
08:12at that time you played tennis.
08:15I jogged and Steve, not so much.
08:18Steve wasn't really into exercise
08:21or healthy diet at the time.
08:23So much to my surprise at the
08:25end of one day when he said you
08:27mind if I jog with you?
08:29And so I said no with a
08:31little smile on my face.
08:32Off we went,
08:33me and my running shorts
08:34and my New Balance shoes.
08:36Steve and his khaki pants and tennis
08:39or sneakers more than and we started
08:42running and after a little while I.
08:45Ratcheted it up and Steve ratcheted it up.
08:48And a little while I did some more
08:50and Steve ratcheted up some more and
08:53pretty soon we were sprinting as
08:55fast as we could with our heads down,
08:57not to some specified gold,
09:00but clearly to see who
09:03would collapse first.
09:04And Steve Rosenberg.
09:07The the unconditioned Steve Rosenberg.
09:11Collapsed about four seconds
09:14before the conditioned.
09:15Vince Devita.
09:18And I tell you, ladies and gentlemen,
09:20that's the last time I beat
09:22Steve Rosenberg at anything.
09:25His talk today is entitled The Lymphocyte,
09:28the Living Drug for the Treatment
09:31of Cancer Doctor Rosenberg.
09:38Well, this is a unique pleasure
09:41for me for several reasons.
09:46It's a pleasure to honor Paul
09:50Calabresi and his family.
09:52Paul a giant in the field of medical
09:56oncology, but also to present
10:01in front of Vince De Vita who.
10:04Has played such an important role in
10:06my ability to do a lot of this work.
10:09Vince is a true giant in the
10:12field of of oncology and his
10:15contributions are known to to you all.
10:20But when I started working at the NCI
10:23trying to develop immunotherapies
10:25for treatment of cancer,
10:27there was not a lot of enthusiasm for it.
10:29But as I initially began to get results.
10:33I remember going to Vince De Vita and saying,
10:36look, I think there's something here
10:39and I'm going to need more resources.
10:42And in a a remarkably generous way,
10:46I was given by Vince De Vita
10:50probably over the objection of many,
10:52I know over the objection of some others,
10:55was given the space and money and
10:57resources to conduct the kinds of
10:59studies that I'll be talking about today.
11:01And it made a huge difference.
11:03To me, we became friends for the past
11:0847 years we worked in a textbook,
11:11Vince's the soul of that textbook and
11:15has led the the process for now through
11:191212 generations of the of the book.
11:22And so to be here to honor Paul Calabresi,
11:25to honor Vince De Vita.
11:28Doctor Weiner,
11:29thank you so much for the invitation to
11:32to come and deliver these remarks today.
11:37So I'll be talking about lymphocytes as a
11:40living drug for the treatment of cancer,
11:42The use of lymphocytes in much the same
11:44way that we might use chemotherapy or other
11:47targeted agents to administer the to the
11:50patient to try to impact on the on the tumor.
11:54And I'll be talking about this
11:56particular kind of immunotherapy and
11:59that is cell transfer immunotherapy
12:02that has many advantages.
12:04One, if we're going to use a
12:05lymphocyte as a drug,
12:06we can grow lymphocytes easily to
12:0810 of the 11 cells or more and
12:11administer very high large numbers
12:13of highly selected cells because we
12:16have the reagent in the test tube.
12:19We can potentially identify the exact
12:21subpopulations and effector functions that
12:24are required for the cancer regression.
12:26And 3rd and very importantly,
12:28we can manipulate the host prior
12:30to the cell transfer in a way that
12:33you cannot do with other forms of
12:35immunotherapy because the cells to be
12:37used are outside the body and we can
12:40therefore alter the microenvironment
12:43of the tumor in ways that will enable.
12:48Immune cells to enter into those
12:51tumors and destroy them.
12:53And so it's the cell therapy that
12:56I'm going to emphasize this morning.
13:03Now cells carry a conventional T cell
13:05receptor and the entire function of
13:08the lymphocyte is dependent on that T
13:10cell receptor to recognize its antigen.
13:13Which in conventional forms for CD8
13:15or CD4 cells, is a processed peptide
13:18coming from inside the cell and put
13:21on the patient's own MHC molecule.
13:24But a little over a decade ago,
13:26chimeric antigen receptors were described
13:31and at the Weitzman Institute.
13:34And that converts A lymphocyte into the
13:37recognition of an antibody not based
13:40on the conventional T cell receptor.
13:42But by making a single chain of
13:45the heavy and light chains of an
13:47antibody and connecting it to
13:50intracellular signaling domains,
13:51we can then use that lymphocyte to
13:55become recognition based on an antibody
13:59rather than on a T cell receptor.
14:02It can recognize cell surface
14:04molecules based on this antibody.
14:07Recognition.
14:07And so it provides us with a whole
14:10other way to identify, identify targets.
14:15And I'd like to spend just a moment on
14:17CAR T cells because although they've
14:19had substantial activity in the
14:21treatment of the hematologic cancers,
14:23they have not had activity against
14:26the solid tumors.
14:28And what's the reason for that?
14:29Well, CAR T cells require the use of
14:32monoclonal antibodies that recognize
14:33molecules on the cell surface.
14:35And they were described by Kohler
14:38and Milstein over 45 years ago.
14:40And despite extraordinary work,
14:41there's not been found a monoclonal
14:44antibody that can distinguish A
14:46malignant from a normal cell.
14:49The antibodies can have a lot of
14:50influence by reacting with cells.
14:51Surface molecules that can affect cell
14:54signaling can affect cell growth.
14:56But we do not have antibodies
14:58that are unique to a cancer.
15:03And that's a problem,
15:04because it's just as easy to kill
15:07a normal cell as a cancer cell,
15:09and we've seen deaths due to
15:11the application of cells that
15:13do not clearly distinguish
15:15between a tumor in a normal cell.
15:17Normal cells are highly,
15:20exquisitely sensitive to.
15:23The expression of monoclonal
15:25antibodies and using ones that
15:27can attack normal cells have
15:29major clinical toxicities and
15:32thus the limitation of cars for
15:35solid tumors is substantial,
15:37and there are as yet now no
15:41known CAR T cell treatments that
15:43are capable of treating in a
15:46reproducible fashion malignant cells.
15:50They are, however.
15:52Potentially very valuable for the
15:55treatment of humanologic malignancies.
15:56And back in 2009, we reported the
16:00first patient to be treated with a
16:03cell therapy that finally got approved
16:05by the Food and Drug Administration.
16:06The only cell therapy now approved and
16:09I'll just spend a moment talking about it.
16:12We had developed models showing we could
16:16treat syngenetic tumors by targeting CD19.
16:19A molecule on virtually all B
16:21cells and B cell malignancies.
16:23We saw a patient with an aggressive
16:26lymphoma in the way it behaved as
16:28you can as you'll see his Xrays,
16:30he's had multiple chemotherapies,
16:33vaccines, checkpoint modulators,
16:35more chemotherapy and finally came to
16:37us in May in 2009 for treatment with.
16:40His own T cells that were genetically
16:43modified with a chimeric antigen receptor
16:46that could recognize CD19 and this is
16:49what his X-ray look like when we treated him.
16:53You can see large masses directed
16:56by these yellow arrows in his
16:59media stymum in his axilla.
17:01Large mediastinal mass, huge spleens,
17:04lymph nodes surrounding
17:05his vena cava and aorta,
17:07huge iliac vessels.
17:09We treated him.
17:11All of his tumor disappeared over
17:15the course of a few months and he
17:17remains disease free to the present.
17:20To the present time.
17:23He had bone marrow replaced which also
17:28disappeared. But you pay the price
17:32because normal cells can also be killed
17:34and B cells disappeared at a time when
17:37normal T cells and natural killer cells
17:39were returning over the course of the
17:42week and 1/2 after the cell infusion.
17:44It took eight or nine months for the
17:47precursors that were not destroyed to to
17:49restore B cells in the in the patient.
17:52But patients can be can survive
17:54for long periods of time in the
17:57absence of any of any B cells.
18:01Well, we treated the 1st 10 patients,
18:03six of them responded.
18:05Five of them are still responding to
18:07the present day over 10 years later.
18:10And in the surgery branch we
18:12received these kinds of results.
18:14We had objective responses by 47 percent.
18:1742% are ongoing and have never recurred out,
18:21with median survivals now beyond eight years.
18:26A good friend of mine, Ari Beldegrand,
18:28had been in my lab 20 years earlier.
18:31We had remained friends and he heard
18:33about some of these responses and after
18:36we had had six complete responders,
18:37he contacted me and said he
18:39wanted to start a company,
18:41Kite Pharma, who went on to do a
18:44multiinstitutional study that almost
18:46exactly reproduced our our results.
18:49We began interacting with Kite
18:51in 2012 through a. A.
18:54A research agreement.
18:56A research and development agreement.
18:59A crater to transfer our technology
19:02to Kite Pharma.
19:03Five years later, they received FDA approval,
19:06along with Novartis,
19:08who had begun working on this a year later.
19:10And in October 2017, Kite,
19:13who has started to do this from nothing,
19:15was told to Gilead Sciences for $11.9
19:18billion and it's now widely available.
19:20This treatment is now widely available
19:23through the United States and Europe
19:24and now beginning in Asia as well.
19:28I think a very proud example of how
19:30findings in an academic and a government
19:33institution can then get translated
19:35to help to help people in in need.
19:41This remains,
19:42however,
19:42the only T cell treatment that
19:45has been approved by the FDA,
19:47although there were several others
19:49that have shown effectiveness
19:50against multiple myeloma that
19:52are have actually just very
19:55recently been been approved.
20:02So here's the problem of
20:04oncology in the United States,
20:06there are about 600,000 cases.
20:09The solid cancers, epithelial cancers
20:12comprise about 90% of all cancers
20:15that cause death in this country,
20:18about 10% of the humanologic cancers.
20:21And the devastating impact of this,
20:23as you can see,
20:24is that one in every two or three
20:26Americans of us will develop an
20:27invasive cancer during our life,
20:29and unless we can find
20:30better ways to treat it,
20:31about one in five will
20:33die of the of the cancer.
20:38And so the major challenge
20:40confronting cancer immunotherapy
20:41today is the development of effective
20:44immunotherapies for patients with
20:46metastatic epithelial solid cancers
20:48that cannot be cured by any available
20:50treatment and result in 90% of all.
20:53Of all cancer deaths,
20:55the checkpoint modulators have had
20:58major impact on some solid tumors like
21:01Melanoma renal cell cancer patients
21:03that have mismatched repair genes.
21:05But the overwhelming majority of
21:08patients with the solid epithelial
21:10cancers do not respond with only
21:12single digit levels of response to the
21:15combined use of checkpoint inhibitors.
21:20So how can we attack these solid
21:22epithelial cancers and I'll talk
21:24mainly about them and but here's a
21:27general cartoon of how we do this.
21:29We excise A tumor.
21:30If you follow me along clockwise,
21:32we follow it excise A tumor.
21:34We grow cells to try to identify cells
21:36with anti tumor activity if we can,
21:39we grow them selectively to large numbers.
21:42We generally infuse 5 * 10 to
21:44the 10th 10 to the 11 cells
21:46and reinfuse them following A.
21:48Non myeloblade of lymphoid depleting
21:51regimen with cyclophosphonine or
21:53fludarabine that will eliminate
21:55T cells for about 8 days before
21:59they normally normally recover.
22:01I'm going to talk primarily
22:03about the epithelial cancers,
22:04but we learned a lot from Melanoma,
22:06so let me spend a moment.
22:07With this lesson,
22:08we treated 192 patients with metastatic
22:11Melanoma with some of these results
22:14that I first showed Vince Stavita
22:16when we had our first lymphocyte
22:18transfer that mediated aggression
22:19of a Melanoma patient in 1988.
22:22As you can see,
22:24we've treated that we did treat
22:25192 patients with their own cells,
22:28their own tumor infiltrating lymphocytes
22:30that we would grow out of the tumor.
22:33Those cells are a sink for
22:35tumor reactive cells.
22:36You can see our objective response
22:38rate by classic recess criteria,
22:39which is the criteria I'll use throughout
22:41this talk with 56% with a quarter
22:44of patients having complete regressions,
22:46only two patients that ever had a
22:49complete regression ever gone on to recur.
22:51The rest of the main disease free
22:53and of these 48 complete responders,
22:56only two patients required
22:57more than a single treatment.
22:59The cells are alive,
23:00they can divide up to 10,000
23:02fold in the first two weeks
23:04after they've been administered.
23:05And that's they patrol the body,
23:07they find,
23:08they find deposits wherever they
23:11wherever the circulation exists.
23:16Well here are our results
23:18in those the overall.
23:19Survival race, progression free
23:22survival race or were about 37%,
23:27but notice the complete responders
23:30very rarely ever recur.
23:32Somehow adoptive cell therapy
23:34appears to eliminate the last
23:36Melanoma cell and so the rest of
23:38the presentation will be on trying
23:40to find factors that we can use
23:42to treat not only Melanoma but
23:45the solid epithelial cancers.
23:46And the first question?
23:47That we'll discuss or what are the
23:50characteristics of the cells that
23:52mediated cancer regression in vivo,
23:56especially to these patients
23:57with Melanoma that have undergone
23:59durable complete regressions.
24:01And to do that we used a high dimensional
24:04single cell transcriptome analysis of
24:06up to 10,000 cells per per patient,
24:09a single very elegant single cell
24:12analysis available 10X from alumina.
24:18Well, because we had a group of patients
24:21that could respond and not respond,
24:23we utilize the single cell
24:26approach to identify the
24:28transcriptome analysis of patients,
24:31comparing responders from non responders.
24:34Because for the first time we had a
24:36group of immunotherapy patients that
24:38were showing this distinction and
24:40when we break all of the lymphocytes.
24:42And their transcriptome analysis
24:44using this these UMAP,
24:46UMAP or typically analysis
24:48using a near neighbor analysis,
24:51you can identify 22 different kinds of
24:54lymphocytes based on their transcriptome,
24:57the messages that they that
25:00they express into proteins.
25:02And there turned out to be one
25:05cluster that seemed to differentiate
25:07responders from non responders.
25:09And when we looked at the transcriptomic
25:12analysis it turned out that only
25:14that cluster cluster number one
25:16could distinguish responding
25:17from non responding patients.
25:19If we looked at the expressed genes
25:22in each of the other 21 clusters,
25:25the responders and the non responders
25:28were virtually identical except in this
25:30cluster that was largely non responders.
25:33It was only cluster number ones
25:36transcriptome that could distinguish.
25:39Responders from non responders and it
25:41turned out that cluster one was highly
25:44enriched in stem like lymphocytes
25:46that do not express CD39 and CD69,
25:50two molecules of lymphocyte
25:53activation and differentiation.
25:57Well,
25:57it appeared therefore that maybe these
26:00CD3969 stem like lymphocytes were
26:02the ones that were most responsible.
26:04For the Melanoma regressions,
26:06because when we looked at the survival
26:09of patients receiving either very
26:11high or low total numbers of cells,
26:14there was no statistical difference
26:16in the outcome of those patients.
26:18But if we now looked at patients
26:21that got either high or low
26:22double negative CD6939,
26:25double negative stem like cells.
26:27There was a highly significant difference
26:30between the cells that were respond,
26:32the patients that were responding to
26:34not responding based on the number
26:37of these double navigative cells
26:38that they that they received highly
26:42statistically significant well.
26:45When we looked at the properties of
26:46these cells, they were true stem cells.
26:48If you divide a lymphocyte
26:51population of till and facts based
26:53on CD39 and 69 expection,
26:55the double positive cells.
26:57When isolated and grow will only
26:59reconstitute themselves double positive.
27:01But when you take the double negative
27:05cells they reconstitute themselves
27:07whereas the double positive cells do not.
27:09They are true stem like cells
27:11when you take cells in one of
27:14our trials targeting Nye cell,
27:16one antigen you can see.
27:19In red,
27:20the double negative cells from the
27:22infusion continued to sustain themselves
27:24as they grew in vitro and were re
27:27stimulated one time after another,
27:29whereas the double positive cells
27:34disappeared as they grew.
27:35They were not stem like,
27:37they could not reproduce their
27:39themselves with their own.
27:41Native reactivities and in fact if
27:43you look at the actual transcriptomes,
27:45it is a stem like markers like K
27:50LF2TCF7CD62L that were expressed
27:53in the response associated culture.
27:56And if you then took this back to the
27:58mouse models that we had initially
28:00studied female mouse model of Melanoma,
28:04you can see that in fact.
28:07These cells when implanted and allowed
28:09to grow for 10 days before treatment
28:11started peripheral blood, they grew.
28:13If you gave double positive cells,
28:15they had some weak reactivity.
28:18But if you gave double negative cells at
28:20two different concentrations including this
28:22very low concentration of 500,000 cells,
28:25the double negative cells could
28:27mediate dramatic anti tumor effects
28:29compared to the bulk populations
28:31and so we could thus identify.
28:34These stem like cells that had a profound
28:38reactivity and published that about two
28:42years ago and have been utilizing it.
28:46We'll talk about some of the
28:47results in the epithelial cancers.
28:49But very recently and in this
28:51unpublished data,
28:52we found that we could actually
28:54make the double positive cells that
28:56were fairly weak work much better if
28:58we could give them a vaccine that
29:00was targeting the same antigens
29:02that the cells were targeting.
29:04And you can see here if we take the
29:06double positive cells which are the most
29:08exhausted of the cells and give them,
29:10they do have some reactivity
29:12compared to the control.
29:14But when you give the double positive,
29:16the double neck,
29:17these double positive cells
29:19in conjunction with a vaccine,
29:20you can now make them very active
29:22and take even 1 centimeter tumors,
29:2520% of the total.
29:285% of the total body weight of the
29:30mouse to disappear completely and
29:33that's something that we're now clinical
29:35trial that we're now initiating.
29:50So we know the kind of cell we want to use.
29:52But what did the till actually recognize
29:55that enables the in vivo control in the
29:58last Melanoma cell And the fact that we
30:00have seen specific regression of cancer
30:02in the absence of any on target but off
30:05tumor toxicities led us to believe.
30:08That we were targeting something completely
30:10unique to cancers and those were the
30:13targets of cancer mutations that we
30:15suspected were the CAR targets of the till.
30:18And so again, to identify the target,
30:21we have to identify this small peptide
30:23that comes from an intracellular
30:24molecule or a molecule that's been
30:26ingested by the cell that can then
30:28be presented to the T cell receptor.
30:32And so about five years ago,
30:33we developed this particular
30:35blueprint for the identification.
30:37Of cells that were recognized by Till
30:40that could mediate tumor regressions.
30:42And what do we do?
30:43If you follow me counterclockwise,
30:45we excise A tumor,
30:47isolate the TILL and extract DNA&amp;RNA from
30:52that till and do whole exome sequencing
30:55so that we could identify every cancer
30:58mutation that was present in that cell.
31:00And we do RN A/C to identify
31:02all the mRNA molecules as well.
31:05We then take those.
31:08Cancer mutations as 25 more molecules
31:11and either as peptides or as mini
31:14genes put together in a tandem
31:16structure to form a tandem mini
31:18gene and put it into a patient's
31:21own antigen presenting cell.
31:23Now that antigen presenting cell
31:24contains all of the MHC molecules of
31:27the patient and if any of these cancer
31:29mutations can then be presented.
31:33On the antigen presenting cell and
31:36recognized by the T cell receptor
31:38of till that forms a signal in
31:41the lymphocyte that enables us to
31:43identify it because of upregulation
31:45of activation markers and we could
31:48then grow those cells selectively.
31:50So again the key is to make a 25 more
31:52peptide with the mutation in the middle
31:55so that any peptide that could be
31:58presented on the MHC surface is concluded.
32:01It could either be the last.
32:03Amino acid of the peptide that's presented,
32:05or the first one,
32:06but it has to be in this 25.
32:08And the advantage of this is there's no
32:10need to do any predicted peptide binding.
32:14Every candidate peptide and all
32:15MHC loci are included in the screen
32:18because both have to be recognized
32:20the peptide on the MHC and there's
32:22no tumor cell lines necessary.
32:23And as you know,
32:24it's very hard to grow tumor cell
32:26lines for most of the epithelial
32:28epithelial cancers.
32:32This can be done within about
32:34two to three weeks,
32:35takes 10 days to do the
32:39to identify all of the
32:40cancer mutation sequences,
32:41another few days to do the
32:44bioinformatic informatic analyses.
32:45And so one has all this information available
32:48within two weeks of the tumor resection.
32:51Well, we started in Melanoma
32:54and evaluated 86 patients.
32:56Those tumors have more mutations
32:58in most 556 as a median.
33:01We screened every mutation that was
33:04expressed that was expressed in RN A/C
33:0715,000 mutations in these 86 patients
33:09to see if any could be recognized by
33:12the patient's own autologous T cell.
33:14So we looked at 218 immunogenic
33:18epitopes 85% of patients could recognize
33:20their own tumor cells based on.
33:22Recognition of these mutations.
33:25Interestingly,
33:25only 1.4% of the mutations could
33:28be recognized because they had it
33:30been cleaved and also presented
33:32on the Mac molecule.
33:33Of that particular patient,
33:3692% were CD8 cells rather than CD Fours.
33:39And our first surprise every
33:42NEO antigen that we recognized,
33:44all 218 were unique to the
33:47individual patient.
33:48Patient's cancer and recognized
33:50by that patient,
33:51none were shared between 2 Melanoma patients.
33:55Well,
33:55we then did this for 130
33:57consecutive gastrointestinal cancers
33:59screened over 15,000.
34:00Of the expressed mutations,
34:031.3% were recognized interestingly
34:05half by CD8 and CD4 cells.
34:08And for the first time we found
34:10an antigen that was recognized
34:11in more than one patient.
34:13It was a KRAS mutation restricted by a
34:16fairly unusual CW8O2 Class 1 molecule.
34:20The other hundred 209 epitopes
34:22that were found were all unique to
34:25the individual individual patient.
34:30True in breast cancer that
34:32we just published last year,
34:3343 consecutive patients 100 immunogenic
34:37epitopes 2.1% were recognized of the
34:40mutations recognized half by mainly by
34:43CD Fours and all were absolutely unique.
34:46And here is an updated as of last September
34:50study of 205 consecutive patients and
34:52note we're talking about the GI cancers,
34:55breast cancer, lung cancer, Gastro,
34:57Gu cancers like ovarian and prostate.
35:00And across the board as you can see
35:04about 70 to 80% of the patients contain
35:08T cells that would recognize their own.
35:13Neo antigens their own cancer mutations that
35:16were presented on their autologous cancer
35:19cells and of this 363 neo antigens we found,
35:23we only found this one K Ras that was
35:26recognized by more than one patient found on
35:29this particular on this particular screen.
35:33Now an advantage of targeting mutations is
35:35its applicability to target multiple cancer.
35:38Types, because we're targeting mutations
35:40and most cancers have mutations,
35:42some more than others.
35:43But let me show you examples of what we've
35:47been able to see an individual patients.
35:51Most do not respond.
35:52I'll show you the overall results soon,
35:55but here are examples of individual
35:58cancers that can respond.
36:00Interestingly, the first patient that
36:02responded to T cells that were unique,
36:04that were identified as uniquely
36:06responsive to our own mutation,
36:08it was under a B2 mutation,
36:10was a 4045 year old woman
36:13with a clangiocarcinoma.
36:14Bile duct cancer had undergone A hepatectomy,
36:17multiple chemotherapy regimens,
36:18developed lung and liver metastases.
36:21We treated her with unselected till
36:23much as we did in Melanoma that does
36:25not work for the epithelial cancers.
36:30Unselected till do work in Melanoma,
36:34but you have to select the
36:36specific ones which are much
36:37rarer in the epithelial cancers.
36:40We gave her those,
36:40she didn't respond. However,
36:42when we use our Tandeminy gene approach,
36:44she had 26 mutations.
36:45We could found that her B2IP
36:47mutation that she recognized it
36:51contained almost 90% the infusion
36:54bag of cells recognized as mutation.
36:57And she underwent a complete
36:59regression of all of her cancer.
37:01You can see her lung cancers
37:06gone. She had three liver metastatic
37:10deposits that disappeared and
37:13she remains now disease free.
37:16Almost 10 years, 10 years later,
37:20this woman who had a metastatic
37:22breast cancer, had been through seven
37:24different treatments for her metastatic
37:27disease to multiple groups, chest,
37:29wall, bone, multiple nodal groups.
37:32She came to us, received cells for treatment.
37:36She received four different what
37:38appeared to be random somatic mutations.
37:40There's no driver function involved in these.
37:45And there was redundancy in the T cell
37:48receptors that we used to treat her.
37:51But by treating these four now random
37:54somatic mutations, she underwent a
37:56complete regression of this lesion
37:57beginning to grow through the cell wall.
37:59You can see multiple liver metastases.
38:01She had many more which disappeared.
38:03And she's over five years later now
38:06completely disease, disease free.
38:07This patient with a metastatic cervical
38:10cancer that was very aggressive and
38:13fungating into her into her vagina.
38:15Underwent resection radiation
38:19therapy and cisplatin chemotherapy.
38:22Underwent our hysterectomy
38:23and excision of both ovaries.
38:26She developed liver, lymph node,
38:28intra abdominal Mets including one
38:30that was obstructing her ureter.
38:31Came to us for treatment with our own till.
38:34You can see these lymph nodes
38:36which disappeared.
38:36This chest wall lesion disappearing
38:39this one as well.
38:40This node was obstructing her ureter.
38:42We put in a urinary catheter.
38:45A a ureteral catheter.
38:46When our tumor went away we
38:48could take it out.
38:49She remains disease free.
38:51Now over seven years later this patient
38:55with colorectal cancer was the one
38:57in which we found the KRS receptor.
38:59It had a colectomy was invading her
39:02bladder she so it was very aggressive.
39:04We resected 2 lung metastasis.
39:06She had seven others treated her and.
39:09Almost all of our tumors disappeared.
39:12She had seven lesions,
39:14six of which disappeared.
39:16This one did not disappear and continued
39:20to grow and where we resected it.
39:22We learned that in fact,
39:24by looking at copy number
39:26analysis of the chromosomes,
39:27she had lost one chromosome from chromosome 6
39:30and that chromosome and codes MHC molecules,
39:33including her restricting element.
39:35Therefore,
39:35that tumor could escape.
39:37And when we then went on to
39:41resect her that one lesion,
39:44she has not occurred since and remains
39:47disease free over six years later.
39:49We can see responses in pancreatic cancer
39:52as you can see this very dramatic.
39:54Response which I show you.
39:56It was a very recent patient
39:59who had what appeared to be
40:00almost a complete regression of
40:02multiple liver methass disease.
40:03But unfortunately within three
40:05months this patient didn't recur.
40:07And when we biopsied one of the lesions,
40:09he had lost expression of his target
40:12molecule which turned out to be
40:14P53 and a molecule that we'll hear
40:17about in a few moments longer.
40:21Well, we've now treated a little over
40:24100 patients with epithelial cancers.
40:26Again, it's the ducts in these
40:28organs that provide the source of
40:30mutations that are turning over
40:32constantly and as mistakes are made,
40:34mutations appear and those
40:36are the ones we're targeting.
40:39If you use bulk till in patients with
40:42epithelial cancers who are chemo,
40:44fract, chemo refractory,
40:45we do not see responses in 21 patients,
40:48but when we started to select these till.
40:52And treated 81 patients,
40:5517% of them have responded.
40:57I've shown you some of them.
40:58These are all patients
41:00that are chemo refractory.
41:02Many had had checkpoint modulators
41:03which do not work in these
41:05tumors and had not responded and.
41:09We have a long ways to go,
41:11but these 17 patients at least
41:14show us that this is possible as
41:16we continue to refine and learn
41:19how to treat these patients.
41:20For the refractory epithelial cancers,
41:24well, there were two hypotheses
41:25that come from this.
41:26First,
41:27it appears to be the recognition
41:29of random somatic mutations.
41:30It's a final common pathway that
41:32explains cancer aggression for most,
41:34if not all immuno therapies.
41:37We finally understand what a cancer
41:40antigen is and as we now look at the
41:43variety of chemother of immunotherapies,
41:45it's now been shown for anti C2A4,
41:47we're studying it fertil tumor
41:50infiltrating lymphocytes as well.
41:52What is a cancer antigen?
41:54It's any intracellular protein
41:56that could potentially be a cancer
41:58antigen if it's mutated and processed
42:01intracellulally to a peptide that
42:04combined to the autologous MHC molecule.
42:06About one in every seventy of these
42:09mutated NEO epitopes are NEO antigens
42:12and there's good news and bad news.
42:14The bad news is that this will have to
42:16be a very highly personalized treatment
42:18after over taking a patient's own cells.
42:21We're targeting A mutation that's
42:24unique to his own tumor and will
42:27therefore be complex to administer.
42:30The good news is that virtually all
42:32cancer patients are potentially eligible
42:34because they all have mutations.
42:36And some more than others.
42:38So the opportunity does exist to
42:41further deliver this treatment and
42:44the complexity will be difficult.
42:46But then again,
42:47I heard that in the early days of
42:49our development of CAR T cells,
42:50several groups came through large
42:52pharmaceutical companies saying,
42:53hey, if we had this disease,
42:55we'd come to you,
42:56but we don't see how to make money doing it.
42:58But I have every confidence that if
42:59we can figure out ways to make it
43:01work and large numbers of patients,
43:03the genius of American industry
43:04will figure out a way to deliver it.
43:08Well there are two main approaches
43:10to using lymphos type transfer
43:11and we've talked about expanding
43:13naturally occurring anti cancer cells.
43:15But because now it becomes so readily usable
43:18to easy to identify T cell receptors,
43:21we can actually identify T cell
43:24receptors into autologous lymphocytes
43:26and expand normal cells and convert
43:28them into anti tumor anti tumor T cells.
43:35We've talked about these non mutated
43:37proteins that are not on normal tissues,
43:40CD19, the unique somatic mutations,
43:43but there are mutations in cancer
43:46driver oncogenes or tumor suppressors
43:48that can be shared among patients.
43:52It's remarkable now that so many different
43:54cancer genomes have been sequenced,
43:56how few of these actually exist that are
43:59shared Far and away the most common are KK,
44:02RASS and P53.
44:04KRS expressing 30% of all cancers,
44:0770% of pancreatic cancer,
44:09it's P53 and half of all cancers.
44:12And so we've made efforts to
44:15identify TCRS from patients that
44:17contain these mutations to find T
44:19cell receptors by doing a highly
44:22directed screening using very high
44:24concentrations of these molecules or by
44:27especially by in vitro sensitization.
44:30To identify T cells,
44:32to identify that very tiny number
44:34that do exist in patients that
44:37can recognize K Ras in P53.
44:41And we published about a year and a half
44:44ago a library of T cell receptors that
44:47are CD8 and CD4 that can recognize K Ras,
44:51the common K Ras hotspot mutations.
44:55Over 80% of OK Ras mutations
44:58occur at three different hotspots,
45:00GG12DG12V and G6 and the 60 oneth
45:06amino acid almost all of them.
45:09However the great majority are
45:10at this K12 and 13 position and
45:13you can see for a variety now of
45:16restriction elements we can identify.
45:19T cell receptors and publish the
45:22sequences of them that can recognize
45:26tumors mutations based on the
45:30recognition of K Ras mutations and a
45:35similar library now of mutations in
45:38K Ras can be recognized by CD4 cells
45:40using a variety of different Class 2
45:43restriction elements And if you look at.
45:46The two libraries that we've now developed,
45:4833% of all patients with K Ras mutations
45:51can potentially be eligible for treatment.
45:54These T cell receptors if we
45:57can learn to use them well,
45:59that led us to the issue of,
46:01well,
46:02what kinds of receptors do we really
46:04want because we can find dozens of
46:07redundant muceptors recognizing the
46:09same exact molecules and there are
46:11a variety of tests that one can
46:13use to test these receptors lytic.
46:15Function, cytokine secretion,
46:16the avidity,
46:17the affinity catch bond techniques.
46:20And so we've gone to try to understand
46:23what T cells do we need so that
46:25we can select the right ones among
46:28the redundant number.
46:29And this brings us back to that patient
46:32with KRAS who was treated with four
46:35different receptors all that recognized KRAS,
46:37you can look here at their.
46:40Avidity,
46:40that is they all recognize about
46:43the same concentration of peptide.
46:45But one of these receptors disappeared
46:49immediately upon infusion and this
46:51was a majority receptor given.
46:54Where are three of these receptors
46:56persisted well out beyond the year?
46:58Here are measurements out to 290 days.
47:01There was something very different
47:03about this receptor compared to these.
47:06What was the difference?
47:08The avidity was the same.
47:11We looked at a variety of criteria,
47:16especially surface plasmon resistance,
47:18to measure the exact KD,
47:21the association constant of that receptor.
47:23What we did is identify the receptor,
47:25clone it, purified it,
47:27and put it into human cells that were
47:30then used to treat the human tumor
47:33and immunosuppressed mice and Notices
47:361 receptor had the highest affinity.
47:39And was the least active in treating mice.
47:44If you look now at this highest
47:47affinity receptor using a mouse,
47:48a human receptor to treat a human tumor
47:51in a highly immunosuppressed mouse,
47:53it was these lower affinity receptors
47:56which were the most effective.
47:59And so it appears that it's not only the
48:01fitness state of the lymphocyte itself,
48:03but the quality of its receptor
48:05that play a role in anti tumor.
48:08Effectiveness well knowing the
48:13receptor that was developed by Eric Tran who
48:16was a fellow in the laboratory who about
48:19the three years ago moved to Portland.
48:22With Eric, we use this receptor that had
48:25the low affinity that seemed to have
48:28that sweet spot of the recognition to
48:30treat a patient with pancreatic cancer.
48:31It was published in the New England Journal.
48:36What about six months ago and you can
48:41see the regression that was reported
48:45with follow up out to six months
48:48of multiple lung metastases which
48:50shrank in that patient to perform
48:53a substantial partial regression.
48:54We have additional follow up now
48:57that patient did recur at one year
48:59but spent one year disease free
49:01of his pancreatic cancer and we
49:04recently just four months ago.
49:06Treated a patient with pancreatic
49:08cancer utilizing a different set
49:10of key res receptors restricted by
49:12a eleven O 1 which is a class 1MHC
49:16molecule and you can see here this
49:19liver metastases which is almost
49:22disappeared by three months this large
49:25one smaller and by three months almost gone.
49:28We're continuing to follow this
49:30patient but this is an approach.
49:32Using T cell receptors into normal
49:34cells that can potentially be effective,
49:37Peter Kim in the Surgery Branch
49:41a fellow has developed a library
49:44mainly using in vitro sensitization
49:47to target P53 molecules.
49:49This was published about six months ago
49:54in Clinical Clinical Cancer Immunology
49:57Research and again these receptors.
50:00Now with some common Class 1 molecules,
50:04O2,
50:04O1 can potentially treat about 5
50:071/2% of all patients with K Ras
50:09mutations and again 50% of all cancer
50:12patients have K Ras mutations.
50:15Well, we could again identify the
50:18T cell receptors that were most
50:20common in recognizing P53 and
50:25recognizing tumors that contain P53.
50:29We isolated those T cell.
50:31Receptors that you uniquely recognize
50:34P53 recognizing tumors and again
50:39studied each one of these 5-6 receptors
50:43that we could find to see which
50:45were most effective and one of them
50:49was more effective than the rest.
50:52Although at high concentrations many
50:54others began to work as well in terms
50:57of cursing in the regression of a
50:59human tumor in a in a in a mouse.
51:01Using human receptors at 27 cells,
51:04you could see many,
51:05several of the receptors were active.
51:08But when you went down to 1/5 of
51:10that a 2E6A tiny number of cells,
51:12this one receptor was most effective
51:14and it was the receptor with
51:16an intermediate affinity.
51:18And so as we continue these experiments,
51:20we're beginning to learn which
51:22kind of receptors we we need.
51:24Well,
51:24having identified that a patient who came in.
51:28With breast cancer,
51:29we've been through multiple chemotherapies
51:32with the highly advanced disease was
51:35treated with our own cells that were
51:38transduced with a high affinity.
51:42Excuse me,
51:42a high avidity but not a high
51:45affinity T cell receptor.
51:47She had very aggressive disease including
51:49a pericardium that was replaced by tumor.
51:52We know that because a week before
51:54we treated her we had to perform a
51:56pericardial window to release fluid
51:58from inside the pericardium and all
51:59of the biopsies here were positive.
52:01She had pleural effusions.
52:02She had tumor covering her her breast
52:06and extending into the into the other breast.
52:09She was treated with our own cells that.
52:12Had been transduced to express
52:14an anti P53 receptor,
52:16this 175 H receptor that I just mentioned.
52:19Every one of these nodules is a
52:22separate tumor deposit at a large
52:24necrotic lesion in our breasts.
52:26All of this, everything visible.
52:30Disappeared and you can see here
52:33at the 60 days the way this breast
52:35looked at six months.
52:37However,
52:37she did recur with a nodule that we
52:41biopsied that had an LOHA loss of
52:44heterozygosity at her MHC locust which
52:46enabled this and other lesions to
52:49escape and so she did recur at six months.
52:58So we can use T cell
53:00receptors to treat patients.
53:01And I'll finish with this very
53:04latest finding we just published
53:05about six months ago in the science
53:08and are beginning to exploit.
53:10And that is a very rapid method to
53:13identify cancer reactive T cell
53:15receptors directly from a resected
53:17tumor without having to do all of the
53:20testing to see what they recognize.
53:22So how do we do this?
53:25We use a single cell transcriptome
53:27analysis of lymphocytes
53:29from freshly resected tumor.
53:33In this analysis,
53:34each cell is bar coded with
53:36an individual DNA sequence and
53:38when that individual cell is
53:40sequenced and you can sequence up
53:42to 10,000 cells at a given time,
53:44the transcriptome all the messenger
53:47RN A's can be analyzed and the T
53:50cell resequence identified and each.
53:53Identified in an individual cell
53:57and so we did that.
54:00And if you then break those lymphocytes
54:03into all of the different clusters,
54:06what you can do is the following
54:10because we have the transcriptome
54:15sequence for every individual cell.
54:20And we've identified the T cell
54:22receptors in that patient that
54:23can recognize the tumor because
54:25every time we identify a cell and
54:27all the patients I've showed you,
54:29we can very easily then get to the T
54:32cell receptor using PCR techniques
54:33to clone it out only takes about
54:36the about two weeks if we look
54:38at this cluster and look at the T
54:41cell receptor sequences that we've
54:43identified for this rectal cancer
54:45patient and see what cells they're in.
54:49They quite astonishingly all appear
54:51in a single transcriptome culture
54:56was true for this breast cancer patient.
54:58In this cluster, we take nine cancer
55:01patients from many different histologies.
55:03You can see they all fit in these
55:06clusters and So what that enables us
55:11to do is identify the gene signature.
55:16Of cells in that cluster because
55:18we know the whole transcriptome,
55:19all the MRN A's expressed and could
55:23identify and report on a gene signature
55:26which we published in Science led
55:28interestingly by a B cell antigen CX, CL13.
55:32And when we take now an
55:35unknown patient cluster,
55:37look for that transcriptome sequencing
55:39that we look for those T cell receptors.
55:42Sequences that fit this gene
55:46signature we could then identify.
55:49For unknown samples,
55:51we could identify cells that
55:52contain that gene signature.
55:54And because the cells are bar coded,
55:55we can immediately get to the T
55:58cell receptor sequence and know that
55:59within a few weeks of the resection.
56:02And when we test each of the TC
56:03R's in that signature right now
56:05and we're trying to define that
56:07signature of the CDH cells.
56:10CD62 percent of all of the T cell
56:13receptors that are present in
56:14that cluster are tumor reactive
56:15and we can identify within weeks.
56:17And CD4 cells it's not quite as good
56:20as about 1/3 of the T cell receptors.
56:22Thus anti tumor T cell receptors
56:24can be quickly identified without
56:27extensive screening.
56:28And use for cell therapy and we haven't
56:32haven't published much of this yet
56:34but but in fact are working hard now
56:37to try to improve our ability to use
56:39T cell receptors for for treatment.
56:46Well, I might conclude with this final,
56:49this final slide and leave you with
56:52these few general conclusions.
56:54Cell transfer therapy can mediate
56:56durable regression in patients with
56:58metastatic cancer refractory to
57:00all other treatments that T cells
57:03recognize unique somatic mutations
57:05and common cancers that identification
57:07and targeting these mutations unique
57:10to each cancer or sometimes shared
57:11mutations such as K, RASM, P53.
57:14Have the potential to extend cell
57:16therapy to patients with the common
57:19epithelial cancers using either
57:21these naturally occurring or T
57:23cell receptor transduced cells.
57:25And finally gene signatures can be
57:28generified generated to identify anti
57:31tumor T cell receptors in fresh tumors
57:34as well as identify the phenotype
57:37of lymphocytes that can improve
57:40functions in eliminating tumor in vivo.
57:44Well, I thank you for your very kind,
57:46kind attention.
57:54Thanks, Steve.
57:55That was inspiring and certainly I know
57:59there were a good number of questions.
58:00I know Diane Krauss has a few online.
58:02But as is our tradition
58:03at the Cal Brazi lecture,
58:05we will often turn to Judge
58:06Cal Brazi or Steven to please
58:08ask the first question.
58:15Doctor Colleridge Son or I'm a law
58:18professor Doctor But I wondered,
58:21would the you're talking about have
58:23any applicability to glioma brain
58:27cancer which I know of especially
58:30hard to treat and which may
58:32become much more common
58:34in the future?
58:35Because there is does seem to be
58:37some evidence that cell phone use.
58:39Increases the risk of coming
58:41down with brain cancer.
58:43So I just wondered, is this applicable
58:45to gliola brain, Brain cancers
58:50plus brain cancers.
58:51Glioblastoma is the most aggressive form of
58:55of the brain cancers do express mutations.
58:58We have identified mutations
59:00in glioblastomas. In fact,
59:02we published a paper on that by
59:05VED Leiko who is a fellow in the
59:07in the surgery branch.
59:09Of a mutation in a glioblastoma,
59:11but we have not treated any glioblastoma
59:15patients with these uniquely reactive cells.
59:19We have treated glioblastomas with CAR
59:21T cells targeting a shared mutation.
59:24And so no responses again because
59:27of the the weakness of of cars
59:30and the potential danger that.
59:32Their tumors might express normal
59:34antigens and in a separate
59:35study that I won't go into,
59:37we actually saw substantial toxicities by
59:40targeting a shared antigen and glioblastomas.
59:43But using this new the new cancer antigens
59:48that result from cancer mutations,
59:50I think should be tried in glioblastoma.
59:52But we have not begun those studies yet
59:55and are concentrating on the more common.
59:58Well, common epithelial cancers.
59:59But it's a wonderful,
01:00:01wonderful idea and something that I
01:00:03hope to to get to in a serious way soon.
01:00:08Question. I wonder if we can unmute
01:00:10her so she can ask it herself.
01:00:13While we're doing that, I'll just ask
01:00:14a question from an anonymous attendee.
01:00:16I have a patient with one of
01:00:18the targetable Rasmutations
01:00:19with the appropriate actual a.
01:00:20What can I do for them?
01:00:21How do I send them
01:00:22to you? We're actively seeking,
01:00:24we're actively seeking those
01:00:26patients. And if you e-mail me
01:00:30sar@nih.gov, I'll see that you get
01:00:32contacted immediately about about that
01:00:34patient to evaluate the eligibility of
01:00:36that patient for our studies. Yeah,
01:00:39I'm guessing that was Diane Kraus.
01:00:40So that Eric would see that he has
01:00:41to put more resource into this
01:00:42so that we'll keep them here.
01:00:43He's he's laughing. OK Diane,
01:00:45are you able to ask your question
01:00:46online or do you want me to
01:00:47read it for you? I can ask it. I can ask
01:00:50my question was why?
01:00:52The selected till work when the
01:00:54bulk till do not for some of
01:00:56these patients with solid tumors,
01:00:58is it a matter of the large dose of
01:01:00the effective till or potentially
01:01:02inhibition by other till that
01:01:04aren't targeting the cancer.
01:01:08We have evidence for both and I think
01:01:11both are important in the animal models
01:01:13in the number of cells you give is very
01:01:16highly related to its effectiveness.
01:01:19In the human, although we generally
01:01:21give us very large numbers of cells,
01:01:24even within the numbers of cells we give,
01:01:26which generally are between 10
01:01:27of the 10 and 10 of the 11,
01:01:29we do see an influence of the
01:01:31number of cells in the likelihood
01:01:34of having complete regressions.
01:01:35And we just published that about
01:01:38a year and a half ago.
01:01:40But we have evidence in animal models.
01:01:43That the normal cells that
01:01:45you give can inhibit.
01:01:46Now if you're giving normal
01:01:49cells that contain T regulatory
01:01:51cells that would be hurtful,
01:01:53but also these other cells that you
01:01:55give that are non tumor reactive
01:01:57compete for the cytokines that are
01:01:59result of the lympho depletion.
01:02:01When you lympho deplete,
01:02:03you increase circulating levels of I
01:02:05L15IL7 which normally do not circulate and.
01:02:10Those circulating cytokines then can
01:02:13impact on the cells we administer and
01:02:15if we're administering normal cells
01:02:16they compete with the good ones.
01:02:18So you've hit your your your question
01:02:22actually hit on the exactly the
01:02:24right answer that you mentioned.
01:02:25You need the right cells and
01:02:27none of the wrong cells.
01:02:29I know we're
01:02:31little over but just two more
01:02:32questions because some of your
01:02:33old friends Mario Snow is online
01:02:34and would like to ask a question.
01:02:36Mario you should have come
01:02:37here in person Mario.
01:02:38Mario. I'm sorry, Steve,
01:02:41I'm just curious for all the
01:02:43reactive TCR's that you found
01:02:44in the epithelium malignancies,
01:02:46are those internally differentiated cells,
01:02:48are there any in the stem cell
01:02:50pool that you say work well and is
01:02:52that different between epithelium
01:02:53malignancies and Melanoma?
01:02:57We can find them easily in Melanoma and
01:02:59they are very difficult to find in,
01:03:02in the epithelial cancers because the.
01:03:07Incidence of those cells are likely
01:03:09100,000 fold less in our measurements
01:03:11in the epithelial cancers than in the
01:03:14melanomas because we generally try
01:03:16to find them in circulating cells.
01:03:18But they do exist,
01:03:20they just very hard to identify.
01:03:21And my suspicion as we continue
01:03:23to study and find better ways to
01:03:25identify tiny numbers of them,
01:03:27we will find them in the in the
01:03:29patients that did that did respond.
01:03:33But it's a particular delight to to
01:03:36hear Mario, who worked closely with
01:03:38us for for several years, as are
01:03:41several others of your of your fellows.
01:03:44We we now have Nick Clement on our on our
01:03:50staff, and it reminds me to say that in fact.
01:03:58Especially all of this work,
01:03:59except for the first five to seven years,
01:04:02was actually done not by me,
01:04:04with my own hands in the lab,
01:04:06but by fellows who come to
01:04:07the surgery branch to train.
01:04:09Fellows like Nick Lemon,
01:04:11like like Mario,
01:04:14who come to the NCI to gain experience
01:04:16in doing clinical and laboratory
01:04:18research for two to three years.
01:04:21And I owe them a great debt, as I do to.
01:04:24Mario, for all the contributions
01:04:26he made when he was here,
01:04:28when he was here with us, you
01:04:29know, Steve, that might be a good way to end.
01:04:31We're going to move into the other
01:04:32room with some of our fellows to talk
01:04:34with you and with the judge and others.
01:04:36Let me just say in hearing you say
01:04:38that the Paul Calabresi I knew would
01:04:40have loved this lecture because it was
01:04:43innovative and it was patient focused.
01:04:45You're bringing new therapies to clinic
01:04:47and Guido's going to say a word,
01:04:48but the fact that you mentored,
01:04:50that was what Paul is all about.
01:04:51And I'm going to go the final word.
01:04:53Judge Guido Calbresi.
01:04:53And then we'll retire to the other room.
01:04:56Judge of
01:05:05course, one people who
01:05:08developed chemotherapy first,
01:05:10he said there was no doubt that
01:05:12where one went was not with
01:05:14chemotherapy but with immune.
01:05:17And he said that was where
01:05:19it would have to be.
01:05:21And that's why I'm particularly
01:05:23delighted to a very.
01:05:26Well, on that note, thank you all.
01:05:28Thank you, Steve.
01:05:28We'll retire and we'll be 5
01:05:29minutes and we'll get you back.
01:05:30Thank you, everyone.