Microenvironmental Determinants of Systemic Therapy Response in Kidney Cancer: from human to mouse and back
March 15, 2024Yale Cancer Center Grand Rounds | March 15, 2024
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- 00:00Real pleasure to introduce Doctor Ari
- 00:02Hakimi as today's Grand Round speaker.
- 00:05He's the an Associate Professor
- 00:06and Co leader of the Translational
- 00:08Kidney Cancer program and Memorial
- 00:10Sloan Kettering Cancer Center. Dr.
- 00:12Hakimi is a urologic surgeon who's
- 00:14focused on the care of patients
- 00:16with urologic malignancies,
- 00:17especially kidney tumors.
- 00:18He received his medical degree in
- 00:20residency training from Einstein
- 00:22College of Madison and completed
- 00:24his fellowship in Urologic Oncology,
- 00:26Oncology and Memorial Sloan
- 00:27Kettering Cancer Center.
- 00:29His research really aims to
- 00:30understand immune infiltration,
- 00:31inflammation in the tumor microenvironment
- 00:33in RCC and to identify novel
- 00:35therapeutic targets to overcome
- 00:37resistance to systemic therapy.
- 00:39His studies apply bulk single
- 00:41cell and spatial RNA sequencing,
- 00:43flow cytometry and immunogenomic analysis.
- 00:46Really to understand both patient
- 00:48samples and a novel immunocompetent
- 00:50kidney cancer mouse line that his
- 00:52lab has developed really has been
- 00:53a game game changer for the study
- 00:55of kidney cancer and particularly
- 00:57the immunobiology of kidney cancer.
- 00:59I followed Ari's work for many,
- 01:01many years now and to see him go
- 01:02from what was a rising star in kidney
- 01:04Cancer Research to now really one of
- 01:06the world leaders has been a pleasure.
- 01:08And it's a a body of work that
- 01:09I've tremendously admired.
- 01:10So it's really a pleasure to be able to walk.
- 01:12Welcome Doctor Akimi to grand rounds today.
- 01:21All right. Thank you so much.
- 01:22And it's really a pleasure to be here
- 01:24at Yale and especially I was especially
- 01:27enthusiastic come here because of David
- 01:31and I mean talk about rising stars.
- 01:32David is incredible and he's got great
- 01:34mentors here with with Harriet and others.
- 01:36And I think it's it's a real pleasure here.
- 01:39So that's my only disclosures,
- 01:40none of which is pertinent
- 01:42to this talk today.
- 01:43So I'll talk a little bit about the genetic,
- 01:46the genomic and genetic background
- 01:48of kidney cancer,
- 01:50in particular clear cell renal cell
- 01:52carcinoma which is the most common and
- 01:54aggressive form of kidney cancer but
- 01:55also one of the most immunoresponsive.
- 01:57We'll talk a little bit about the
- 01:59role of the micro environment as a
- 02:02predictive response and really focus
- 02:03on myeloid compartment which is one
- 02:06of my lab's interests a little bit
- 02:08from the genomic determinants of this
- 02:10and then some of the insights using
- 02:12both human and mouse strategies to
- 02:15understand this for for future targeting.
- 02:17So kidney cancer is about is the
- 02:206th most common cancer overall or
- 02:23eighth most common cancer overall,
- 02:256th most common in men.
- 02:26There's a 2 to one gender difference
- 02:28and we know that you know within
- 02:30the kidney there are many,
- 02:31many subtypes of kidney cancer and even
- 02:33if you just took the most common subtypes,
- 02:36they're very genetically different.
- 02:37Clear cell represents the most common form.
- 02:40About 6570% of all kidney tumors are
- 02:43a clear cell and we know the most
- 02:45about it from a genetic standpoint.
- 02:47But we also,
- 02:48there's also some very intriguing
- 02:49phenomenon that existed in it,
- 02:50particularly the amount of the
- 02:52immune response.
- 02:53And it's still not clear why these
- 02:55tumors are so immune infiltrated and
- 02:56and why they are so responsive to
- 02:59immunotherapy compared to other tumors
- 03:01that are much more highly mutated,
- 03:03for example like melanomas or or
- 03:05bladder lung cancers where you see
- 03:06a lot of mutations in those tumors.
- 03:08And probably you know everyone
- 03:11references TCGA papers initially in
- 03:14terms of the fundamental understanding.
- 03:16And I think some of the takeaways
- 03:17from this tumor from this analysis
- 03:19which is one of the first tumors to be
- 03:21profiled was that it's really dominated
- 03:22by a few driver mutations related to
- 03:25tumor suppressors On the 3P locus.
- 03:28There's not a lot of mutations.
- 03:29There's some copy number events that
- 03:31are really fundamental and maybe some
- 03:33of which are enriched in metastases.
- 03:35But there's not an obvious clue as
- 03:37to you know why these tumors retain
- 03:40such a high immune infiltration.
- 03:42We also know a little bit about what happens.
- 03:44Thanks to Seminole work from the
- 03:46Sanger Institute where they looked
- 03:48at what were the fundamental events
- 03:49that that are associated with clear
- 03:51cell nasal carcinoma development.
- 03:53And what this paper showed for the
- 03:56really the first time was that
- 03:58the loss of chromosome 3P1 arm is
- 04:02critical to the oncogenesis and then
- 04:04that's followed by VHL loss whether
- 04:06it's mutations or or methylation.
- 04:08But basically 90% of all clear cells
- 04:11have this and then eventually over time
- 04:13additional driver mutations are lost and that
- 04:16leads to different evolutionary subtypes.
- 04:18And in this paper Samara Trashlik and others
- 04:22came up with a relatively complex schema.
- 04:25But you know, fundamentally you can
- 04:27think about it as the tumors lose
- 04:29VHL and then they usually acquire
- 04:31one or two additional hits to form
- 04:33into sort of different trajectories.
- 04:35We know that tumors that lose PBM one and
- 04:38set D2 for example maybe more angiogenic,
- 04:41they may they may tend to be a
- 04:43little bit more indolent overall,
- 04:45maybe possibly more responsive to certain
- 04:47therapies like including even immunotherapy
- 04:49although that's not entirely clear.
- 04:51And then BAP one mutations which occurs
- 04:53well are are typically associated with
- 04:55more high grade aggressive proliferative
- 04:57tumor types and then you can have multiple
- 05:00clonal drivers which also represent a
- 05:02very aggressive form of kidney cancer.
- 05:03So we're starting to get a better
- 05:05framework for the underlying genomics,
- 05:07but none of this really has been
- 05:08shown to be targetable.
- 05:09So for years we just really started to
- 05:12understand what was driving kidney cancer,
- 05:14but we really didn't,
- 05:15wasn't giving us any further insights,
- 05:16weren't an oncogene that you
- 05:17could develop a target to.
- 05:18And while people are certainly working
- 05:21on epigenetic regulation and strategies,
- 05:24it's it's certainly not an obvious pathway
- 05:27forward in kidney cancer at least right now.
- 05:29And at the same time,
- 05:30we also knew clinically that that
- 05:32you know most of the targeted
- 05:33therapies were limited to the micro
- 05:35environment of the of the cancer.
- 05:37And really we've seen a tremendous
- 05:39growth in in outcomes and survival
- 05:41for kidney cancer patients.
- 05:43But it's all really focusing
- 05:44on the micro environment.
- 05:45So even back in,
- 05:46in the 90s when we were studying IL 2
- 05:49both in melanomas and kidney cancers,
- 05:51that was really the only
- 05:53treatment that seemed to work.
- 05:54We had tried all the chemotherapies
- 05:56you can imagine in the 80s,
- 05:5890s and you would see responses
- 06:01even 7 to 10% cures,
- 06:03but with very,
- 06:04very high toxicity in those
- 06:06populations and in those patients.
- 06:08And it wasn't until the advent of
- 06:10of really by work from Bill Kalin
- 06:13and others where we recognized the
- 06:14importance of Hifs that all these
- 06:16focus on VEGF had come around.
- 06:17And then it wasn't really until this
- 06:20notion of immunotherapy came around that
- 06:23we started to see this big revolution
- 06:25in terms of survival and outcomes.
- 06:27But it's all really focused on,
- 06:28on the micro environment.
- 06:31We know that you can take some
- 06:33of these genetic events that I
- 06:35mentioned earlier and risk stratify
- 06:37patients a little further.
- 06:38This is the work that we did several
- 06:40years ago now looking at the impact
- 06:43of some of these common mutations
- 06:45and outcomes for patients that were
- 06:47receiving VEGF therapy and it was
- 06:49you know prognostic maybe you could
- 06:51further stratify patients that
- 06:52were grouped into clinical risk
- 06:54groups by by common mutations.
- 06:56But it wasn't really telling us anything
- 06:58about the underlying immunobiology or
- 07:01angiogenic biology in these tumors.
- 07:02It was really more just a
- 07:04prognostic feature about it.
- 07:06So with this revolution of
- 07:09immunotherapies both by themselves
- 07:11and in combination with VEDF therapy,
- 07:13we've seen the the survival rate and
- 07:15the response rates go up dramatically.
- 07:17So you know the median survival when
- 07:18when I first started my training
- 07:20for metastatic kidney cancer was
- 07:22you know a year and a half or so
- 07:24and now we're pushing five years
- 07:25for for a lot of patients and and
- 07:28potentially curing some patients.
- 07:30And we there's a real need to
- 07:32understand why that's the case and
- 07:34how we can do better because we
- 07:35know that invariably most patients
- 07:37despite this high response rate will
- 07:40eventually develop resistance and you
- 07:43know understanding why that's the case
- 07:45requires you know good models to do.
- 07:47So we know that from an immunotherapy
- 07:51standpoint that it's not ATMB driven
- 07:53tumor at least not obviously and
- 07:55maybe you can break down the types
- 07:57of mutations a little bit more.
- 07:58I was just talking to David about
- 08:00this last night,
- 08:01but you know there's it's not obvious.
- 08:04There have been several attempts
- 08:05to look at TMB as a predictor for
- 08:07responses and most of the large clinical
- 08:08trials that have been performed that
- 08:10have have released their data have
- 08:11not shown this and certainly David
- 08:13has been on the forefront of this.
- 08:14But if you look across some of
- 08:16the major phase three trials that
- 08:18have at least released their data,
- 08:20there's not a really a signal at all
- 08:22with respect tumor mutation burden.
- 08:23We've looked in David and others have
- 08:26looked at whether mutations in PBM one
- 08:28or loss of nine P which is a common
- 08:31event in metastatic kidney cancers,
- 08:33whether that's associated with
- 08:34immune infiltration patterns.
- 08:35There may be some signals there.
- 08:38It's not a clear biomarker though and
- 08:40and that sort of has been lacking from a
- 08:42mutational and copy number standpoint.
- 08:44So I think one of the things that
- 08:46is unique about kidney cancer is
- 08:47that you know we've started to look
- 08:49many years ago now at transcriptomic
- 08:51predictors because the mutations
- 08:53are clearly and copy number of
- 08:55events are clearly not sufficient to
- 08:57determine who's going to respond at
- 09:00least from a biomarker standpoint.
- 09:01And you can just take a very simple
- 09:04metric of the uniqueness of kidney
- 09:06cancer and this I just plot out you
- 09:08know VEGFA and CD8 infiltration.
- 09:10This was an older slide,
- 09:11but I like showing it 'cause I think it
- 09:13shows the uniqueness of kidney cancer,
- 09:15clear cell,
- 09:15at least with respect to some of
- 09:17the micro environmental genes.
- 09:19And we know that they're just
- 09:21dominated by high infiltration of CD8
- 09:24cells and high angiogenic programs.
- 09:26So the question of course and this
- 09:27was shown across cancers and it's
- 09:29really distinct from its from the,
- 09:31from the normal tissue.
- 09:32If you look at for example lung cancers,
- 09:35many,
- 09:36much of the lung itself is very
- 09:38mean infiltrated
- 09:38likely due to smoking or other
- 09:40other carcinogenic features.
- 09:41But the kidney itself,
- 09:43the normal kidney is not
- 09:44particularly mean infiltrated,
- 09:45but the tumors are often very
- 09:47dramatically infiltrated.
- 09:48So there's something very distinct
- 09:50about the actual tumor itself
- 09:52rather than the underlying organ
- 09:54that it's that's derived from.
- 09:56This is work we did when when I
- 09:58was just starting out and we we
- 10:00you know we we we used immune
- 10:02deconvolution strategies to show this.
- 10:04You could take signatures for
- 10:08T cells or for macrophages,
- 10:11NK cells etcetera.
- 10:12And you can start just deconvoluting
- 10:15bulk RNA sequencing data and start
- 10:17to try to understand where tumors
- 10:19or particular samples might might
- 10:21fall in a spectrum and and you
- 10:23can use this to also subgroup.
- 10:25So we use this strategy to kind of
- 10:27think about tumor micro environmental
- 10:29subgroups within kidney cancer and
- 10:30this was our first attempt about
- 10:32eight or nine years ago to look at you
- 10:34know whether there's these enriched
- 10:36groups and whether there's you know
- 10:38other groups within kidney cancer.
- 10:40Maybe that would sort of explain why you
- 10:42see some some really great responses
- 10:43in the streaming top And we we did
- 10:46see that we saw you could clearly see
- 10:48these T cell infiltrated clusters.
- 10:49You could see at this point we really
- 10:51didn't think about angiogenesis,
- 10:52but in retrospect you know you've
- 10:54seen angiogenic cluster and we'll
- 10:56talk more about that in a minute.
- 10:57And you know it did correlate with
- 11:00certain genetic programs mostly
- 11:01antigen presenting machinery programs.
- 11:04So there was an up regulation of antigen
- 11:07presenting machinery transcript,
- 11:08but it wasn't clear still from this
- 11:10point what was actually driving this.
- 11:12We we looked at genetics,
- 11:15common mutations and wasn't at
- 11:17least obvious at the time when
- 11:18we first did this study,
- 11:19although that's evolved a bit and
- 11:21that same approach was applied by
- 11:23Genentech when they first published
- 11:25and then analyze the EMOTION trial.
- 11:27This was the first attempt to
- 11:29combine VEGF and IO therapies.
- 11:30They used tizolizumab and bevacizumab,
- 11:33which is a VEGF monoclonal antibody.
- 11:36And this,
- 11:36this trial was negative in terms
- 11:38of improving the standard of care,
- 11:40but it was biomarker.
- 11:41Biomarker Rich and I give a lot of
- 11:44credit to Genentech for not only doing
- 11:46phenomenal genomic work but also
- 11:48making it all publicly available,
- 11:50which is something that other companies
- 11:51have have been a little reluctant to do.
- 11:53So and maybe it was because it
- 11:55was a negative study,
- 11:55they were willing to share so much,
- 11:56but it really was very helpful.
- 11:58And David McDermott and others from
- 12:02Boston performed really the first
- 12:04type of analysis in the context
- 12:06of systemic therapy to show that
- 12:08these micro environmental groups
- 12:10angiogenesis and T cell infiltration
- 12:12and myeloid programs may stratify
- 12:14patients into different groups but
- 12:16also may associate with response.
- 12:18And one thing I would point out I
- 12:20think it it it's sort of logical
- 12:21that a tumor that may have a lot of
- 12:24T effector cells would respond well
- 12:25to amitotherapy.
- 12:26But you know what they also showed
- 12:29was that myeloid populations as as
- 12:31determined by again a gene program
- 12:33we're we're driving resistance also.
- 12:36So you could be AT effect or
- 12:38high tumor but if you had a high
- 12:41myeloid program it could supersede
- 12:42that impact and and and in fact
- 12:45actually show you know dramatically
- 12:46different responses in that context.
- 12:48So that really sort of laid the groundwork
- 12:50for not only the micro environment
- 12:52relevant but also it could it could
- 12:54predict responses and maybe give us
- 12:56some insight into into resistance.
- 12:58We applied that same strategy initially
- 13:01to just a VEGF cohort only and this was
- 13:03work that I did with with Bob Moecher,
- 13:05one of my mentors at at Sloan
- 13:07Kettering for many years.
- 13:08And this was just looking at
- 13:10the first trial that compared
- 13:12two different VEGF inhibitors.
- 13:14At the time we had really sunitinib
- 13:16and this was the first attempt to try
- 13:19a different strategy or a different
- 13:21VEGF inhibitor and you know it was
- 13:23really more to look at tolerability.
- 13:26There was no difference really in
- 13:27responses but actually Piszopinib
- 13:28but this you know showed a better
- 13:31toxicity profile for patients.
- 13:32So that became the standard of
- 13:33care ELISA Memorial for many years
- 13:35until obviously we developed next
- 13:37generations and immunotherapies.
- 13:38But at this time we took a
- 13:40transcriptomic approach.
- 13:40So we had microarray data from
- 13:44Novartis and we had looked at this
- 13:46question of whether you can identify
- 13:47subgroups and we found you know 4
- 13:49transcriptomic subgroups at the time
- 13:51they tended to really stratify patients.
- 13:53Again,
- 13:53all these patients received EDF first line,
- 13:55so clean,
- 13:56clean cohort and you could clearly
- 13:58see a difference in in groups.
- 14:00And there was a green group here
- 14:01that was very responsive and a red
- 14:02group that was very not responsive.
- 14:04And then there was these yellow and
- 14:05blue in the middle and the green
- 14:07group really had a lot of angiogenic
- 14:08program and that made sense, right?
- 14:10You know, if you have a lot of angiogenesis,
- 14:13it makes sense that you would
- 14:15respond very well.
- 14:16But the red group which was #4,
- 14:18that was the one that didn't respond well.
- 14:20They were actually the worst but they had
- 14:22the second highest amount of angiogenesis.
- 14:23So why why was that the case?
- 14:24Why didn't they stratify nicely by
- 14:27by angiogenic program and and when we
- 14:29compared that group to the other groups,
- 14:31we could see that it was really
- 14:32being dominated by a myeloid program.
- 14:34So despite having high angiogenic
- 14:37phenotype or transcript,
- 14:38they were they were reversing the
- 14:41response based on an infiltration of
- 14:44myeloid myeloids at least inferred
- 14:46by by microarray data.
- 14:49So,
- 14:50so that suggested that it could
- 14:53actually be driving a response overall
- 14:56and the micro environment may be
- 14:58useful in understanding biomarkers in in,
- 15:01in metastatic kidney cancer.
- 15:03And then actually this was something
- 15:04that we did and at the end and
- 15:05actually the my fellow at the time,
- 15:06one of the urology fellows at
- 15:07the time who was working in,
- 15:08in my group actually had the
- 15:10suggestion that we look,
- 15:11we kind of left them all together
- 15:13because there's open Evans Sunitnib,
- 15:14we're sort of both VEGF inhibitors.
- 15:16But we know that the TKIS target
- 15:18lots of different kinases,
- 15:20not they're not super specific
- 15:22and actually if you look at the
- 15:25macrophage and angiogenic groups,
- 15:26you could actually see that
- 15:28Pizzopinib has quite a different
- 15:31stratification than tsunitiv.
- 15:31This suggests to us we we didn't
- 15:33talk about too much in the paper,
- 15:35but it it really suggested that the
- 15:37targets of these TKIS may also actually
- 15:39be driving some of their responses.
- 15:40So some of these kinases are present on
- 15:43on immune cell populations for example.
- 15:45And the fact that these biomarkers
- 15:47were actually different with respect
- 15:49to the different Tkis was something
- 15:51that that we've now followed up on.
- 15:53And I think it's a really
- 15:55interesting finding that he made.
- 15:56And this just leads back to the
- 15:58same concept that what what Dave
- 16:00showed in in this in this beautiful
- 16:02paper from the from the Genentech
- 16:04study others have looked at micro
- 16:06environmental features in other
- 16:08in other more positive trials.
- 16:09So this,
- 16:10this was also sort of a negative,
- 16:11well not negative but has not has
- 16:14not been brought forward further.
- 16:16This was the Javelin 101 study again
- 16:20avolumab and exitinib again another
- 16:22combination of PD one and and and VEGF
- 16:26and they focused on a a lymphocytic
- 16:31signature identified 26 genes again
- 16:34specific signature for specific trial.
- 16:36Some of the challenges of these have been
- 16:38you know applying it to other data sets.
- 16:39But again you could see the the
- 16:42micro environmental features being
- 16:44associated with response here
- 16:46and suggesting you know that we
- 16:48could utilize this as a strategy.
- 16:50And then there have been subsequent
- 16:52efforts by by collaborative
- 16:55groups including Genentech again
- 16:57to integrate what we know about
- 16:59mutations and those evolutionary
- 17:01subtypes I showed you earlier into
- 17:03and the micro environmental feature.
- 17:05So if we have the micro environment
- 17:07and we know the genetics that are
- 17:09that arise as kidney cancers evolve,
- 17:12could they could they be sort of
- 17:14grouped together to form these kind
- 17:16of different molecular subgroups?
- 17:18And I think there's been some
- 17:19attempt to do this.
- 17:20I think it's improving,
- 17:22but you know you sort of have the sense
- 17:24that there are these different angiogenic,
- 17:26stromal and angiogenic alone.
- 17:27So some of these may have this
- 17:29myeloid phenotype that I showed you
- 17:31earlier and just a purely angiogenic
- 17:33tumor maybe the purely angiogenic
- 17:35tumors would respond really well to
- 17:37VEGF alone and those are tend to
- 17:39be the less aggressive tumors PBR 1
- 17:41mutated and then you have the ones
- 17:43that are myeloid and angiogenic
- 17:45and those actually don't respond
- 17:46at all to to VEGF inhibitors and
- 17:48then you have these proliferative
- 17:49ones and and other ones.
- 17:50So we're starting to get a sense
- 17:52that maybe you can subgroup kidney
- 17:54cancers into those features.
- 17:55And then came along this
- 17:57notion of single cell.
- 17:59And there have been a series of papers,
- 18:01one of which David LED,
- 18:02but that came out from the time
- 18:03because we had done all of all
- 18:05this work on bulk RNA sequencing.
- 18:07And as the fields across
- 18:09cancers have evolved,
- 18:10we started utilizing single cell to not only
- 18:13get a better sense of what was happening,
- 18:17but also really understand you know
- 18:18what are the specific features of these of,
- 18:21of the of the micro environment
- 18:22in a much more high resolution.
- 18:23So the advantage of bulk RNAC of
- 18:25course is that you can do big,
- 18:26big numbers of samples because
- 18:28it's relatively inexpensive.
- 18:30Single cell gives you deep dive,
- 18:31but often the cohorts were
- 18:32much more modest in size.
- 18:34So I think there's constantly
- 18:35a need to go back and forth.
- 18:36If you find a signal in one,
- 18:37you have to validate in the
- 18:39other so to speak.
- 18:40And so we we we did this in in
- 18:44clear cell focusing really on
- 18:46patients that had received just dual
- 18:49immunotherapy with PD1 and CTLA 4.
- 18:52We focused on 6 patients initially.
- 18:55When we did this together with Ming Lee,
- 18:57one of my immunology mentors,
- 18:59Christina Leslie,
- 18:59who's a computational biologist and a very,
- 19:01very talented graduate student at the
- 19:03time who's finishing his post doc at Harvard,
- 19:06now Shirag Krishna.
- 19:07And we looked at patients that had
- 19:10either were were high risk and not
- 19:14had not received PD one right away or
- 19:17versus ones that had had Ipinivo. Yeah.
- 19:21And were eventually went on to surgery.
- 19:24One of the unique things I I do
- 19:25as a surgeon is that we're able
- 19:27to get tissue after treatment and
- 19:28kidney cancer has evolved so much
- 19:30so because of the response rates
- 19:32now to upfront immunotherapy that
- 19:33most patients if they come in with
- 19:35metastatic disease will get upfront
- 19:37systemic therapy and then we're being
- 19:39asked to operate on them later on.
- 19:41So that gives us a unique opportunity
- 19:43to study tissue after treatment,
- 19:44which is something I think really
- 19:46unique to kidney cancer amongst many
- 19:48solid tumors we have this opportunity.
- 19:49So we were able to utilize that
- 19:51strategy here and this sort of
- 19:53gave us a broader sense and this
- 19:54has been replicated I think by
- 19:56many other single cell studies
- 19:57including David's really Seminole
- 19:58work in this and you can kind of
- 20:01get a sense of what's happening now.
- 20:02One of the things that's interesting
- 20:04about a quirk of single cell is that
- 20:07you know there's for those of you
- 20:09familiar with the technology is that
- 20:10you know there's generally at least if
- 20:12you do single cell and not single nucleus,
- 20:14you have to do some sort of
- 20:16sorting and a lot of the.
- 20:18Tumor cell populations actually
- 20:19die die off from that process.
- 20:20They're very fragile for some ironically
- 20:23and immune cells will often survive
- 20:25although you lose neutrophils.
- 20:27So kind of interesting quirk
- 20:29of any sort of single
- 20:31cell study that you do, you lose a
- 20:33lot of the cancer cell populations.
- 20:34But we're able to kind of get a
- 20:35good sense of what's going on in the
- 20:37immune cell population and you get
- 20:38a general sense that and this has
- 20:39been replicated by our flow analysis
- 20:41over the many years that about 6040
- 20:44to 60% of the immune compartment is,
- 20:46is made-up of T cell and you have
- 20:49a good amount of Tams in this.
- 20:51And then a whole bunch of other
- 20:53populations including B cells and K
- 20:55cells and dendritic cell populations,
- 20:57but they're really dominated by these T
- 21:00cell and and and and and Tam populations
- 21:03and you could further phenotype them
- 21:04into you know and this has been done.
- 21:06You know,
- 21:07everyone's got their own slightly different
- 21:08way of of phenotyping populations,
- 21:10but this allows to sort of get a
- 21:13sense of what's happening, yeah,
- 21:14in both primary sensitivity and
- 21:16and primary resistant patients.
- 21:18And you know this one again we
- 21:20had epinivo resistant and a mixed
- 21:22response and a complete response,
- 21:24complete response patients are always
- 21:25interesting because why are we operating
- 21:27on them if they have a complete response?
- 21:28Well, when I say complete response,
- 21:30I mean that the tumor's
- 21:32mass itself is not viable.
- 21:33It's it's it, it there's a mass there,
- 21:35we we take it out.
- 21:36But actually under the microscope,
- 21:38there's no tumor left.
- 21:39It's just a conglomerate of
- 21:40immune cells and fibroblasts.
- 21:43And so that's kind of an interesting
- 21:44population to look at because
- 21:45what's what's residual there.
- 21:46And there we found these tissue
- 21:49resident T cell populations that
- 21:51were very abundant in the in the
- 21:54in the residual mass of the of the
- 21:56of that of that kidney even though
- 21:58it was there was no tumor left.
- 22:00And then we found within the
- 22:01patients that were not responding
- 22:03it really you know there was T cells
- 22:05there but it was really dominated
- 22:06by specific Tam populations.
- 22:08This was a primary resistant patient.
- 22:09He had had big tumor, big lymph nodes.
- 22:11We gave him a trial with Epinivo to
- 22:13see if that would help and it didn't.
- 22:14So we still end up operating on him,
- 22:16no response in the tumor whatsoever.
- 22:18And you could see this was really
- 22:20a Tam dominated tumor type.
- 22:21So it started giving us insights
- 22:22that really this may be associated
- 22:24again small numbers.
- 22:25So you really have to start building
- 22:27that out and you can develop
- 22:28signatures which is what we did.
- 22:29We actually took the single cell genes
- 22:32and from the different clusters and
- 22:34overlaid them on some of these genomic
- 22:37signatures that have been published.
- 22:38The javelin when I mentioned the the,
- 22:40the,
- 22:40the genomic ones from Genentech and we
- 22:43started saying like what are the actual
- 22:45populations that they're capturing.
- 22:47You get a better sense that there
- 22:49are some dominant Tam populations
- 22:51and that some of these populations
- 22:53may be potentially targetable.
- 22:54And I'll talk about that in in a
- 22:57moment. But I want to bring your
- 22:59attention to some of these adenosine
- 23:01signatures that were were published
- 23:03from an HUAR inhibitor which is
- 23:05something that has been shown to
- 23:07potentially shift Tam phenotypes.
- 23:08So, so this was sort of an interesting
- 23:10way for us to look at the data and
- 23:12you can develop signatures based on
- 23:13the single cell data and compare them
- 23:16to existing signatures to see if you
- 23:19could further stratify patients and
- 23:21responses across different different data
- 23:23sets And and we were able to do that.
- 23:25And then the question is also, well,
- 23:27is there a relationship between the
- 23:29underlying micro genetic micro environment
- 23:32and these specific immune micro environments?
- 23:35So I I showed you again on bulk,
- 23:37maybe there's these different
- 23:38sub classifications,
- 23:39but we also know there's a lot of
- 23:41heterogeneity in kidney tumors, right.
- 23:42So we know that if you took a kidney
- 23:44tumor and you sequence different regions,
- 23:46Charlie Swanton showed this many years
- 23:48ago in a famous paper New England Journal,
- 23:49intratumal heterogeneity exists.
- 23:51Does that same thing apply to
- 23:53the micro environment as well?
- 23:54And that's something of of course
- 23:56if you're going to develop a
- 23:57biomarker or suggest something,
- 23:59you have to think about that.
- 24:00And this is work that we did in
- 24:02collaboration with Illumina where we
- 24:03really thought about this question of,
- 24:05OK,
- 24:05now we have a good sense of what's
- 24:06going on in the micro environment.
- 24:08We have a good sense of what's
- 24:09going on in the underlying
- 24:10genomics and and how does that,
- 24:11how does that relate to the individual tumor.
- 24:13And one of the reasons why clinically
- 24:15that's interesting is 'cause if you
- 24:17look at at at data sets where the the
- 24:19primary tumor's still in place in
- 24:21the with the patient with metastatic
- 24:22disease and they get immunotherapy,
- 24:24often the Mets will respond well,
- 24:25but the primary tumors maybe
- 24:27only shrink modestly, right.
- 24:28So there's not a,
- 24:29there's not that same level of response.
- 24:31And one hypothesis is that,
- 24:32well,
- 24:33it's because the primary tumor is
- 24:35more clonally diverse and the Mets
- 24:36is just a a clone that was able to
- 24:38metastasize out that was selected for.
- 24:40So when you get a response in the
- 24:42Mets maybe it's because there's just
- 24:44a clone that's really responsive,
- 24:45but the primary may only have that
- 24:47clone in in part of it and sort
- 24:48of been our rationalization for
- 24:49continuing to operate on these
- 24:51patients because I tell them well
- 24:52a you know I like operating.
- 24:55But more more fundamentally it's
- 24:57actually because we think that you
- 24:59know we're we're removing the diverse,
- 25:00the biological diversity of them Even
- 25:01if they've had a good response up front,
- 25:03the chance for them to develop persistence
- 25:05down the road may come from from the primary.
- 25:08And so we tried to look at this with
- 25:10multi regional sequencing again
- 25:12relatively modest numbers but we
- 25:14we utilized the combinations of DNA
- 25:16and RNA and and TCR and different
- 25:18things within within tumors that
- 25:20had been exposed to
- 25:22immunotherapies as part of a
- 25:24trial that we ran and and others.
- 25:26And so we were able to look at the
- 25:28question of whether overall immune
- 25:30diversity is associated with,
- 25:32I'm sorry, overall genetic diversity
- 25:34is associated with particular micro
- 25:36micro environmental phenotypes.
- 25:37Indeed, we found at least in this
- 25:39study that if you were a very high lead
- 25:41diverse tumor from a genomic sample,
- 25:43you were more likely to be
- 25:44a myeloid high tumor,
- 25:45which was interesting and and vice
- 25:48versa with respect to some of the
- 25:51antigen presenting machinery genes.
- 25:52So the ITH tumors were actually
- 25:55lower with respect to the APM genes
- 25:57and actually if you took a specific
- 25:59tumor and you actually marked out
- 26:02the immune infiltration patterns,
- 26:04you could start seeing evolution
- 26:05within that same tumor.
- 26:06So this is an example of a of
- 26:08a tumor that was I TH high.
- 26:09It had a lot of intratumoral heterogeneity.
- 26:11It was AP Bear Monsanti 2 kind of
- 26:14micro environment or evolutionary
- 26:16subtype and we were able to look
- 26:18at individually in different
- 26:19regions of this tumor to see.
- 26:20We found that some of the regions
- 26:22were very T cell infiltrated at
- 26:23least by RNA and some of them
- 26:25were very mild and infiltrated.
- 26:26And we were actually able to
- 26:27track down like what were the
- 26:28individual genetic events that were
- 26:30occurring as this tumor developed.
- 26:31And you could see that, you know,
- 26:32as the tumor developed,
- 26:34there was loss of HLA and maybe some
- 26:36CDK into A&B loss which has been
- 26:38associated with a more immune desert
- 26:41or less immune infiltrated micro.
- 26:43So within the same tumor itself,
- 26:44you could see this evolution and
- 26:46that was correlating with the micro
- 26:48environmental features suggesting
- 26:49that there's this constant interplay
- 26:50And I think David has shown this and
- 26:52others have suggested this constant
- 26:54interplay between the underlying Genoma
- 26:56architecture of a tumor and what's actually,
- 26:58you know,
- 26:59underlying the response micro
- 27:00environmentally in that tumor.
- 27:01Obviously we don't fully tease
- 27:03out the mechanism here at all,
- 27:04but it begs the question that there's
- 27:07an opportunity here to to explore this
- 27:10and what about in in the metastatic question.
- 27:11So that was another
- 27:12question we had in the lab.
- 27:14So I've showed you everything in terms
- 27:15of treatment response potentially.
- 27:17But we also wanted to know are are
- 27:19these micro environmental groups
- 27:21also predicting or or associating
- 27:23with development of metastas,
- 27:24which is a different question,
- 27:25right.
- 27:26You know you could have a micro
- 27:27environment that's really
- 27:28important for treatment response,
- 27:29but it may not be associated
- 27:31with metastatic development.
- 27:32So,
- 27:33so David had had somewhat hinted at
- 27:36this with his work with with Ellie
- 27:38and Tony and others at Dana Farber
- 27:41and they showed it you know very
- 27:43elegantly in this paper that looked
- 27:45our paper focused on the advanced
- 27:47disease and and Ibidevo treated.
- 27:49But David's work was performing single
- 27:52cell sequencing on early locally
- 27:54advanced in metastatic tumors and
- 27:56at least in this work he showed this
- 27:58evidence of T cell exhaustion but
- 28:00also this shift in the macrophage
- 28:01polarity as tumors became more
- 28:03aggressive, more metastatic.
- 28:04So suggesting to us and others that
- 28:06you know maybe some of these Tams and
- 28:09and myeloid populations that were so,
- 28:11so, so driving responses are also
- 28:14associated with metastatic development.
- 28:16And so for this we again utilize
- 28:19our strategy with with going
- 28:21to clinical trials and and we
- 28:23worked with this adjuvant study.
- 28:25So this was one of the series of
- 28:27negative studies unfortunately,
- 28:28but again the benefit of having a lot
- 28:30of genomic data looking at whether
- 28:32giving it a VEGF inhibitor monotherapy.
- 28:34Again Pezopinib in this case was
- 28:36associated with better outcomes
- 28:37in patients with high risk non
- 28:39metastatic kidney cancer.
- 28:39All these patients in this trial
- 28:41had advanced kidney cancers.
- 28:42They had a high risk of relapse but
- 28:47but you know standard at the time
- 28:48was just to observe them and so there
- 28:50was a series of trials to see if you
- 28:52gave a VEGF inhibitor whether that
- 28:54actually was improved their survival.
- 28:57The vast majority of the studies were
- 28:59were -1 was sort of positive but no
- 29:01one has really adopted it and now
- 29:03we've moved on to immunotherapy but at
- 29:05this time this was a very interesting study.
- 29:07So we we compared we had microarray
- 29:09yet again from Novartis,
- 29:10we compared the the again all high risk.
- 29:13So they're they're you're sort
- 29:14of controlling for the potential
- 29:16tumor confounding features right.
- 29:17They're all high risk patients and
- 29:18we compared the ones that relapsed
- 29:20versus the ones that didn't.
- 29:21This is work that one of our one of
- 29:23our fellows LED and who who's now at
- 29:26Rochester with a surgeon scientist
- 29:28track their great guy Phil Rippolt
- 29:30with with Lynn Von from my lab who's
- 29:33a senior member now and we compared
- 29:35the the tumors that record versus
- 29:36didn't and we used an unbiased you know
- 29:38whole genome approach with with this.
- 29:39And so of course you saw things
- 29:42like EMT and mtor,
- 29:44which made sense to us because
- 29:45those are obviously very known
- 29:47and relevant oncogenic processes
- 29:48that that promote metastases.
- 29:49But we also saw a lot of immune
- 29:52inflammatory genes in particular Illinois
- 29:546 and Jack in Stat 3 kind of stood out
- 29:57to us as being a driver of metastasis.
- 30:00Again,
- 30:00we applied the same single cell
- 30:02strategies what we had done before to
- 30:04see you know what are these myeloid
- 30:06inflammation and Illinois 6 pathways,
- 30:09what are they really converging on?
- 30:10And and and indeed it it showed a
- 30:14real enrichment in some of these tan
- 30:16populations that we had defined a
- 30:18little bit better with the single cell data.
- 30:21And suggesting that if you were a tumor
- 30:23that was myeloid high or adenosine high,
- 30:25similar overlapping signatures,
- 30:27you are more likely to develop metastasis.
- 30:30Again controlling for other features,
- 30:32all of the clinical and pathologic features.
- 30:34These are completely independent programs
- 30:37and you could show that if I mean if
- 30:40you were a AMSK inflammatory signature,
- 30:42which was a gene signature we developed
- 30:44from from the micro RAY data strongly
- 30:46overlapping with the myeloid signature
- 30:48from Genentech and others that you could
- 30:51take all these high risk patients.
- 30:52And really I mean it's pretty amazing
- 30:54to see curves like this separate out.
- 30:56But again all of these patients,
- 30:58this is a myeloid load tumor intermediate
- 31:00and then very high and you could
- 31:02see their survival probability.
- 31:03And then we were able to replicate this
- 31:05in multiple other data sets including
- 31:07from one of our former fellows who's
- 31:09at Moffett now and and again showing
- 31:11that if you were controlling for
- 31:12all these high risk features from
- 31:14a clinical pathologic standpoint,
- 31:16you you could still stratify patients
- 31:17by the risk of recurrence in that
- 31:20and it didn't seem to be associated
- 31:22much with the T cell response.
- 31:24So what was driving metastas is
- 31:26at least in this data set,
- 31:27but again it has been valid in others,
- 31:29was not really AT cell driven process.
- 31:31What was at least from a micro
- 31:34environmental standpoint promoting
- 31:35metastasis was was independent seen.
- 31:37We tried all the different T cell
- 31:38signatures that have been shown.
- 31:40We looked at IHC scores,
- 31:41we had IHC from CD8 infiltration
- 31:44patterns here.
- 31:44We were able to see if they were inflamed
- 31:46or excludeded and we really didn't see me.
- 31:48Maybe there's a signal with the
- 31:50desert that those are the tumors
- 31:52that have no T cells at all,
- 31:53but it wasn't clear at least that was
- 31:55that wasn't the clear driver here.
- 31:57It was really much more of the myeloid
- 31:59and Tam phenotypes and actually the
- 32:01angiogenic tumors that were low
- 32:03were also similarly associated,
- 32:05not quite as clean of a signal,
- 32:06but it's certainly it looks like if
- 32:08you're a low angiogenic tumor you're
- 32:10you're much more likely to recur.
- 32:11So this suggested that these micro
- 32:13environmental features also might
- 32:15be useful for adjuvant strategies
- 32:17and indeed a lot of the work now
- 32:19that's going forward in some of the
- 32:21newer adjuvant trials are factoring
- 32:23in things like these transcriptonic
- 32:25signatures into risk adapted models.
- 32:26And I think you know the future of
- 32:28course would would would incorporate
- 32:30some of these into selecting not only
- 32:32who's going to recur or not but maybe
- 32:34whether you give them a combination
- 32:36strategy or a single agent drug.
- 32:37But how can we test this.
- 32:38So ultimately you know I I show a lot of
- 32:41like nice kind of genomic correlative
- 32:44work and maybe some evolution of how
- 32:46we think about kidney cancer from a
- 32:49micro environmental and genomic standpoint,
- 32:50but really how do we test this.
- 32:51And so this is the challenge that I faced.
- 32:53I was kind of writing all these
- 32:55papers and thinking about this a lot
- 32:56and getting advice from mentors and
- 32:58everyone kept saying well you got to,
- 32:59you got to,
- 33:00you got to find a model that that works.
- 33:02And so you know we didn't have a
- 33:04lot of good models at the time and
- 33:06I'm going to talk about one we've
- 33:07we've developed a
- 33:08second which which I think is
- 33:09maybe even better, but I'm going
- 33:10to talk about the first one today.
- 33:12So. So you know there are some
- 33:15genetic models in kidney cancer.
- 33:17The, the one that was was used
- 33:19really until this time was really
- 33:21the Renka model which is for those
- 33:23of you familiar it spontaneously
- 33:25arose in a valve C mouse which is
- 33:28immunocompetent mouse and it was called
- 33:30the renal cortical Adam carcinoma.
- 33:31Back then we we really had very
- 33:33limited understanding but it has
- 33:35been profiled now and we know
- 33:36that it's not a VHL driven tumor.
- 33:38So VHL as I showed you earlier is is
- 33:40the fundamental event in in clear
- 33:42cell you have to have a VHL mutation
- 33:43to be a clear cell really and and so,
- 33:48so it was used forever.
- 33:50GEM models of course we know the
- 33:52genetics so why can't we just use
- 33:54gems and there are there are many
- 33:55many GEM models you can probably
- 33:57find six or seven out there.
- 33:59They're often from mixed mixed backgrounds.
- 34:01They have a very long tumor initiation time,
- 34:04very low lower tumor petitrins
- 34:06compared to other gems and they're
- 34:09very hard to transplant and often
- 34:10they develop cystic renal failure
- 34:12because when you knock out even in
- 34:14a KSP specific or Cree specific
- 34:17kidney specific fashion you will,
- 34:19you'll often develop cystic renal
- 34:20failure which is what you see in in
- 34:22people with hereditary kidney cancers.
- 34:24Many of them especially with
- 34:25VHL will develop many,
- 34:26many cysts in their kidney
- 34:27in addition to tumors.
- 34:28So,
- 34:29so it's hard to use those models.
- 34:31So we teamed up with Scott Lowe
- 34:33together and Scott Lowe is for those
- 34:36of you not familiar with him is very,
- 34:38very compass scientists at Memorial
- 34:39and does a lot of mouse engineering
- 34:42beautiful ways and we used an
- 34:43electroporation strategy at the time
- 34:45which would allowed us to deliver guides.
- 34:47We focused on a actually interesting
- 34:49combination of genes which are not
- 34:51super common in kidney cancer,
- 34:52but they define and I'll show you
- 34:54in a minute some of the myeloid
- 34:55phenotypes which is one of the
- 34:57reasons why we focus on it is there
- 34:59also happen to be a very nice gem
- 35:00from Ian Frus group in in Germany.
- 35:02It's time that utilize VHRB and
- 35:05P53 and showed very nicely a gem
- 35:07that which we had been using in the
- 35:09lab for many years and I'll show
- 35:10you some of that work in a minute.
- 35:12But we had utilized this strategy
- 35:14because a because Scott had utilizing
- 35:16P53 in a lot of different tumour
- 35:18models and he had very good guides
- 35:20for and very good strategies,
- 35:21but also because of the genetic
- 35:23combination and also because of
- 35:25the myeloid phenotypes.
- 35:26This was sort of our strategy at
- 35:28the time and this was not trivial
- 35:30because we had VHL as the backbone
- 35:32and that that that makes cells
- 35:34very tricky to add additional guys.
- 35:36For some reason when when you
- 35:38when you knockout VHL
- 35:39in vitro the cells don't
- 35:41tolerate it very well.
- 35:42They they senesce they they.
- 35:44And so this was about a year and
- 35:46a half of work that Lynn did.
- 35:48And eventually though we were able
- 35:49to develop a tumor that we could
- 35:51transplant and we were able to
- 35:53show transcriptomically that this
- 35:54matched into that myeloid high
- 35:56group that that Bob Moitzer and
- 35:58others from Genentech had shown
- 35:59to be critical for that cluster.
- 36:01The the, the very aggressive one
- 36:03that seems to be resistant to to
- 36:05vegif and I can show you here
- 36:07you know this was that cluster
- 36:08here it's P53 enriched 30%.
- 36:10Again P53 is not commonly seen
- 36:12in localized kidney cancer,
- 36:14but if you look at metastatic
- 36:16cohorts it's about between 10
- 36:17and 30% of those will have them.
- 36:19And so this is really the
- 36:21stromal proliferative cluster.
- 36:22When you do flow cytology analysis on it,
- 36:27they they're very macrophage and rich
- 36:29tumors and they have AP 53 program.
- 36:32When you look at transcriptomics,
- 36:33it's very similar to that group.
- 36:35And as I mentioned there was this
- 36:36adenosine signature that we saw which
- 36:38overlap with the myeloid sector.
- 36:39This,
- 36:40this actually came from this paper that
- 36:42was published in from UCSF from Fong ET al.
- 36:46In combination with with Corvis
- 36:48which is a biotech company.
- 36:50And they had developed an adenosine
- 36:532 receptor blockade therapy for
- 36:56patients with metastatic kidney
- 36:58cancer that were treatment refractory
- 36:59and they had developed a signature
- 37:01which which was very much overlapping
- 37:02with this myeloid signature.
- 37:04So this gave us the thought of OK,
- 37:05well we showed that this myeloid program is
- 37:08so important for metastasis development.
- 37:10Maybe if we targeted this adenosine
- 37:12pathway this could abrogate metastasis.
- 37:14And So what Lynn did in her model
- 37:17when she developed it was was
- 37:19stored sort of started testing
- 37:21CP1444 is this adenosine inhibitor.
- 37:22And we were able to show that you
- 37:24get this dramatic abrogation of
- 37:25metastasis doesn't fully control it,
- 37:27but the the number of Mets and the
- 37:30development of Mets is abrogated
- 37:32quite dramatically using a myeloid
- 37:33depletion strategy or a specific
- 37:35myeloid depletion strategy.
- 37:36It doesn't deplete all Tams,
- 37:37but it does shift the phenotype of
- 37:39some of the Tams quite dramatically
- 37:41suggesting perhaps that this could be
- 37:43a strategy and utilizing a mouse model.
- 37:46In the background of all this,
- 37:47we've also you know really been
- 37:50thinking about how to utilize the
- 37:53micro environment to study resistance.
- 37:56And so again we had to go back to
- 37:58a mouse model and I I showed this
- 38:00engineering model which we developed.
- 38:01But we're in the background of all this.
- 38:02For many years we had been utilizing
- 38:04this gem and we we utilize this
- 38:07gem from Ian Frue ET all this.
- 38:09Again this was a KSP, sorry Cree,
- 38:12ERT 2 KSP 1 Flocks mouse that had lost VHL,
- 38:17PT3 and RB.
- 38:18They develop pretty nice clear cell
- 38:21tumors and we utilize this model to to
- 38:23actually study some of these questions.
- 38:26We want to understand what's
- 38:28happening with both PD1 and VEGF
- 38:31therapies alone and in combination.
- 38:33Again I showed you the the real
- 38:35the relevance of this from a
- 38:37predicting response standpoint.
- 38:38And so we first looked at these
- 38:40tumors genomic this is this is
- 38:43unpublished data but hopefully will
- 38:45be submitted in the next few months.
- 38:47So, so we we started looking at these
- 38:49KVPR tumors that had from this Ian
- 38:51fruit model again validating the fact
- 38:52that they are really representative
- 38:54of this myeloid high tumor that I had
- 38:57shown you earlier from from Bob's work.
- 38:58This is again showing RNA sequencing
- 39:00from from from many tumors that we
- 39:02have from these mice and that they
- 39:04overlap very nicely with the the myeloid
- 39:06high PV 3 driven tumors in in human.
- 39:11And we started treating these mice
- 39:13and really focusing on a combination
- 39:14strategy which I think is near to dear
- 39:17Harriet from her from work in Melanoma.
- 39:19But we we utilized linvanib and and PD
- 39:22one in combination for a few reasons.
- 39:24One we were very interested in levanim
- 39:25and PD one comma that that has the
- 39:27highest overall response rate.
- 39:28If you look at the clinical trials,
- 39:30it's about 75% of patients will have
- 39:33a first line response which is really,
- 39:34really incredible and and also we
- 39:39know that Lenva has potentially a
- 39:41lot of micro environmental targets
- 39:43beyond just veg F So so we're very
- 39:46interested in this question and we
- 39:47utilized a sort of a mouse clinical
- 39:49trial from this work.
- 39:50We also included though ACSF 1 inhibitor
- 39:54BLZ 945 to see if if we just broadly
- 39:56depleting Tam's would be helpful.
- 39:58And I should note that CSF one and
- 40:00our inhibitors have been have been
- 40:02a DUD in the clinic.
- 40:03Primarily because they they tend
- 40:05to deplete lots of Tams and Tams
- 40:06can be good and they can be bad.
- 40:08So we don't really we we weren't
- 40:10really didn't really know what to
- 40:11expect here and I'll just show some
- 40:13of that data and we did single
- 40:14cell on pretty much all of these
- 40:17mice that we developed tumors from
- 40:19in different categories.
- 40:20And we and we this to this,
- 40:21this model actually is quite
- 40:23sensitive to linvatinib and actually
- 40:25the combination is is pretty
- 40:26dramatically responsive here.
- 40:27But they don't respond at all to
- 40:30PD1 and actually CSF ONE inhibitors
- 40:31don't really do anything at all.
- 40:32So we were then also able to take
- 40:36early responders and resistant and and
- 40:38actually start comparing them as well.
- 40:40So we can look at the impacts on
- 40:42the micro environment from these
- 40:44different treatment strategies alone
- 40:45in combination and in resistance and
- 40:48in sensitivity which is which is
- 40:50really I think something you want to do.
- 40:51And we could take single cell data
- 40:53from this same strategy that we
- 40:54applied before and start looking at
- 40:56the differences between responders
- 40:57and non responders between ones that
- 40:59are in combination or or alone and
- 41:02get a sense of what's really driving us.
- 41:04You know one of the interesting
- 41:06things about this single cell data
- 41:07set was that we actually had a
- 41:09lot of neutrophil populations and
- 41:11we don't really know their role.
- 41:12I mean there's been some really nice
- 41:14work from Taha Murgoob and Jed Walchak
- 41:16recently on the on on on neutrophils
- 41:18roles in in immunotherapy strategies.
- 41:22So it's an emergency,
- 41:22but I'm not going to talk about
- 41:23that too much today,
- 41:24but it was a striking finding here
- 41:26and we could further subtype the
- 41:28macrophage clusters within here
- 41:29and understand what's happening.
- 41:31It's a, it's a very Tam dominated tumor
- 41:33type as I mentioned with the P53 and RB.
- 41:37And we can actually further stratify
- 41:39them and to understand what's actually
- 41:41happening in the context of both
- 41:43therapeutic sensitivity and resistance.
- 41:45And you can start to see that certain Tams
- 41:46are associated with response and certain
- 41:48Tams are associated with resistance.
- 41:50So even though if you just deplete all Tams,
- 41:52you would actually lose that effect.
- 41:54But actually if you understood which
- 41:55Tams which tumor associated macrophages
- 41:56are actually associated with response,
- 41:58these Angio hide Tams,
- 41:59Tams that are producing angiogenic genes
- 42:01which maybe have been reflected by some of
- 42:03those Angio bulk RNA sequencing data earlier,
- 42:05they're actually associated with response.
- 42:06Whereas other Tams,
- 42:07maybe those myeloid high Angio
- 42:09hide tumors that don't respond are
- 42:11actually associated with resistance.
- 42:12So now we can start getting further into
- 42:15the phenotypes of these Tams and and
- 42:17the context of treatment strategies.
- 42:18And for the sake of time,
- 42:20I won't talk about the neutrophils,
- 42:21but it is another story and we
- 42:24can actually use neutrophils to
- 42:26associate again further responses.
- 42:27So perhaps there's a a major role for them
- 42:29and I don't have time to talk about it.
- 42:31But then then of course you have
- 42:32to go back to the human right,
- 42:33because I showed you something in mouse.
- 42:34But are there analogous populations
- 42:36in human post treatment, right,
- 42:38Because if you're going to,
- 42:39you can cure lots of mice,
- 42:40but you don't know if if those,
- 42:42if those populations are are
- 42:45relevant to human biology and that's
- 42:47a major challenge for immuno,
- 42:48immuno genomic studies or immunologies
- 42:51immunotherapy related studies because
- 42:53of course the mouse and the human micro
- 42:56environments are can be quite different.
- 42:58So that requires post treatment tissue.
- 43:01So how do you do that?
- 43:01So that's you know some of the beauty
- 43:04about going back and forth in in my group.
- 43:07So this is work that was led by
- 43:09Steven Reese who's graduating from
- 43:11our program this year.
- 43:12He's spent a year with me in the lab
- 43:14and a whole whole including a lot of
- 43:17very talented pathologists and research
- 43:19pathologists and of course Christina
- 43:20Leslie from the Computational Biology.
- 43:23And we and we we took all these patients
- 43:24that we've been operating on over the years.
- 43:26Now we started to define them
- 43:28into categories right of of early
- 43:30response of a complete response,
- 43:32partial response and and no response.
- 43:34These are patients that Pat operates
- 43:36on all the time and and I operate on
- 43:39quite a bit and these are patients
- 43:40that that are post immunotherapy
- 43:42now which is a new new frontier.
- 43:44A lot of our surgery now is now in the
- 43:46in the post IO space that gives you a very,
- 43:48very unique opportunity to actually
- 43:50study what's happening both within
- 43:52and across tumors.
- 43:53And so this this is allows us to
- 43:56assemble cohorts of patients that have
- 43:58been exposed to IO therapy alone to
- 44:00IOTKI therapy and we have some with
- 44:04just TKLO but that's really not done anymore.
- 44:06So,
- 44:07so essentially we can look at
- 44:09responses both defined
- 44:10clinically, radiographically but
- 44:11also pathologically and understand
- 44:13are there what are the populations
- 44:15in human and are they analogous to
- 44:17the mouse of course which is you know
- 44:19something that I you know really want
- 44:21to do what we really want to focus on.
- 44:25And so you can start defining
- 44:26this different ways.
- 44:27This hasn't been,
- 44:28there's not an official Canon
- 44:30here on how to do this.
- 44:31It's sort of been adopted a lot from
- 44:33the Melanoma literature about how
- 44:35to define true pathologic response.
- 44:37A lot of us have looked at you
- 44:38know complete response where
- 44:39there's no residual viable tumor,
- 44:40RVT, residual viable tumor or
- 44:42near complete response.
- 44:43And those patients actually if you
- 44:45if you take their their kidneys out
- 44:47we we showed and and we'll show in in
- 44:48our paper that you know they have really,
- 44:50really durable responses you know many,
- 44:52many years without even off therapy.
- 44:54So that's a it's a good biomarker for
- 44:56how they're going to do down the road.
- 44:57And then you can have these partial
- 44:59responses where they have this in
- 45:00between and you have these non responses
- 45:01where there's really no treatment response.
- 45:03You can see it all within the
- 45:05tumor and you could do single cell
- 45:07sequencing on these cohorts and
- 45:09start to get obviously in the human.
- 45:10You still see a lot more T cells as
- 45:12I showed you earlier from the work
- 45:13that we did and what David has done.
- 45:15But you can see these tan populations
- 45:17here and then you can overlay work that.
- 45:19Andrew Corners,
- 45:20who's an MD medical oncology fellow
- 45:23working with Ming Lee has done
- 45:26a lot of this work now.
- 45:27And we can start seeing what are
- 45:29the differences between the IO only
- 45:31and the IOTKI and the untreated
- 45:32populations in terms of the single cell,
- 45:34again post treatment populations
- 45:36and we can start focusing on some
- 45:39of these same populations that we
- 45:41saw that and then we can actually
- 45:44overlay the mouse Tam signatures
- 45:46onto these populations to see other
- 45:48analogous populations and are they
- 45:50associated with resistance and
- 45:51response both within the tumors
- 45:53and across the different regions.
- 45:54And that's sort of where we're focusing now.
- 45:56And so we can further substratify
- 45:58the Tams just like I showed you in
- 46:00the mouse and to see are the TKII
- 46:02iOS really depleting some of these.
- 46:04This is just looking at them broadly
- 46:06without looking at resistance.
- 46:07But you can start seeing that that the
- 46:09the different populations are being
- 46:11affected in different ways by the
- 46:13different treatments in maybe similar ways,
- 46:15but I'm sure different
- 46:16ways as well as the mouse.
- 46:18But hopefully that will help us hone
- 46:19in on what are the most relevant
- 46:21targets to try in the mouse.
- 46:23And you can see this if you focus
- 46:24on one of the M0 signatures from
- 46:25the mouse that I showed you,
- 46:27that Cape, that GEM mouse.
- 46:28You can see that there's clearly
- 46:31differences in terms of the
- 46:33TKIO combination patients
- 46:34and in in the upper tail and the
- 46:36lower tail on this platter actually
- 46:38associating with resistance and response.
- 46:39So you get a sense that maybe
- 46:41these populations are relevant
- 46:43across you know species.
- 46:44So that I think is sort of
- 46:46where we're headed. So overall
- 46:50my conclusions really are that RNA
- 46:52signatures and immune response
- 46:53are really the the useful ones.
- 46:54Clinically I showed you sort of
- 46:56the genetic recap of kidney cancers
- 46:58and how it might relate to some
- 47:00of these microviomal feature.
- 47:01But that's really what we have from
- 47:03a from a predictive and prognostic
- 47:06standpoint and maybe it'll help us
- 47:08select adjuvant treatment strategies
- 47:09down the road for patients,
- 47:11certainly pick the high risk patients
- 47:13a little bit better perhaps the the
- 47:16phenotype seems to be enriched in
- 47:17the in the map in the metastatic
- 47:19setting and particularly post IO.
- 47:22And and maybe this this cross
- 47:24analysis will allow us to prioritize
- 47:26targets to test pre clinically and
- 47:28then hopefully bring them out to
- 47:30the to the clinic now that more
- 47:31and more companies are interested
- 47:33in in targeting tan populations
- 47:35with different inhibitors.
- 47:37And I want to obviously thank my funding
- 47:39and of course, members of my lab,
- 47:41Ming Lee's lab, the urology department,
- 47:43Christina Leslie from computational biology
- 47:45and all the medical colleges I work with,
- 47:47particularly Doctor Mozer,
- 47:48who's been a wonderful mentor to me for many,
- 47:50many years.
- 47:52Thank you so much.
- 47:53And I'll have you answer any questions.
- 48:09Thanks, Ari.
- 48:09That was a real Tour de force.
- 48:12I have a question about the
- 48:14complexity of your clustering.
- 48:15So I I noted that you had 21 clusters of
- 48:19myeloid cells in one of your figures,
- 48:22I believe it was one of the mouse figures.
- 48:25Yeah. Well so that's sort of the art and the
- 48:30the dark art of of single cell sequencing.
- 48:32You could, you can cluster any
- 48:34way you want and you can set your
- 48:36parameters quite differently. So yeah,
- 48:38and this is all all my Lloyd populations,
- 48:42you're absolutely right.
- 48:42So one of the things we do then of course is,
- 48:45is then go back with my immunology
- 48:48colleagues and actually start
- 48:49to think about what are the,
- 48:50what are what are really representing
- 48:52unique populations versus just
- 48:54slicing and dicing single cell data
- 48:56in more and more complex ways.
- 48:58And we try to validate them by
- 49:01flow and to look at really the
- 49:02the dominant populations there.
- 49:03So it's just that this is just
- 49:05sort of an early iteration of of
- 49:08what would be real clustering.
- 49:09No, I get it and it's,
- 49:10it is really complicated
- 49:12before treatment on treatment.
- 49:13But my other question is spatially
- 49:14are some of the clusters uniquely
- 49:16positioned in a certain area of the
- 49:18large tumours that's in humans,
- 49:20I guess is where I'm interested.
- 49:21Yeah, yeah.
- 49:21So,
- 49:22so in that same cohort that I
- 49:23showed you that we're doing,
- 49:25we're working with Heartland Jackson
- 49:28who's at who's in Toronto who's
- 49:31spatial mass cytometry kind of person.
- 49:33We developed from the single cell
- 49:36data a series of of populations
- 49:38really relying on most of the human.
- 49:40So we we took a conglomerate of
- 49:42the different single cell studies
- 49:43that David has done and others have
- 49:45done and kind of come up with like
- 49:47a meta analysis of what are the
- 49:49key markers of the different Tam
- 49:51populations to reduce it down to
- 49:53maybe five or six that might you know,
- 49:56you tag a Tam by you know CD 68 or
- 49:58something else and then you can add
- 50:00a few additional markers and then
- 50:01look at the spatial orientation
- 50:03in these contexts.
- 50:04So we're we're taking all these
- 50:06regions both within tumors and
- 50:08across tumors and and reducing it
- 50:10down to probably a core.
- 50:11And I think ultimately from
- 50:12a biomarker standpoint,
- 50:13you want to kind of just be able to
- 50:15choose a particular Tam or particular
- 50:17T cell that would be relevant and
- 50:18just reduce it to a couple quick
- 50:20stains that a pathologist could
- 50:22hopefully do as opposed to have to do
- 50:24fancy and very expensive sequencing.
- 50:26So absolutely thinking about the same
- 50:28same questions that you bring up.
- 50:30Thank you.
- 50:31I guess I haven't
- 50:35not. I got an unrelated 1
- 50:37unrelated the mouse cell line.
- 50:39So thank you for sending us and sharing that.
- 50:41Of course, the cell line with us.
- 50:43You're planning on making additional ones
- 50:44with different genetic proteins. Yeah.
- 50:46So that's real community service, yes.
- 50:48Yeah. So, so we, yeah, we are doing,
- 50:50we have a VHLBA P1 CD can to be,
- 50:52which is a more common combination and
- 50:55that one is a sarcomatoid tumor perfectly
- 50:58responds well to CTLA 4 very nicely.
- 51:03So that one yeah we'll be hopefully
- 51:06that's that papers you know we're
- 51:08finishing up this that work but
- 51:09that I think that will be something
- 51:11that people find more exciting just
- 51:13because of the common genetics.
- 51:15In fact when I presented this one
- 51:17initially Bill very Bill Kalin very,
- 51:19very astutely said you know that's
- 51:21not a very common genetic study.
- 51:23I'm like yeah but that's it's a
- 51:25common one for the for the bad
- 51:27tumors that don't respond well.
- 51:28So so this one is is a much more
- 51:31common genetic subtype and I it's a
- 51:34challenge of doing anything engineering.
- 51:35We tried of course all the the more
- 51:38common mutations as has Bill and
- 51:40others you know Crisp bring out PBR
- 51:43and what the tumors just don't grow
- 51:45well and they're very hard so the the
- 51:47nice clear cells are hard to engineer.
- 51:50The bad ones that don't look super
- 51:52clear cell but have they retain the CA
- 51:559 and hip one at least don't don't look
- 51:57you know those are the ones that grow.
- 51:59It's it's a challenge of any
- 52:01syngeneic system.
- 52:02So that's why you know you can rely on
- 52:04gems but gems are just hard to to treat.
- 52:06So limitation of the field
- 52:11sure.
- 52:15Thank you. So so really great work in
- 52:17terms of single cell transcriptomics and
- 52:20even profiling and site off and such.
- 52:22But ultimately the biomarker should be
- 52:25translated into clinic and should be
- 52:27easily performed and reputable and cheap.
- 52:29So how do you envision translating these,
- 52:32yeah, into the clinic? That's great.
- 52:34So a couple couple ways.
- 52:35And I think we're thinking about
- 52:36this a few different ways.
- 52:37So one of course is where obviously
- 52:41reducing it to a few markers that might
- 52:43stand for the most relevant populations
- 52:45and maybe it's a combination of Tams,
- 52:47maybe some neutrophils and some CDA
- 52:49populations that might ultimately come
- 52:51up with a very straightforward IHC panel.
- 52:53The other thing of course is that what
- 52:55a lot of people are thinking about
- 52:57is digital pathology and sort of AI.
- 52:59So if you can define groups of tumors
- 53:02transcriptionally and then you you
- 53:04put it into some model where you have
- 53:06the scan slide scanned in and and put
- 53:08through a machine learning platform.
- 53:10You could maybe even digitally say
- 53:11this is this tumor has this feature
- 53:13even though the pathologist has
- 53:15no idea what they're seeing,
- 53:16but the the model does.
- 53:18And so for that,
- 53:18you know and I know a lot of
- 53:20people are working on this,
- 53:20but we you know for that same
- 53:22Novartis study where I showed you,
- 53:23we showed that the myeloid phenotype
- 53:25is associated with recurrence.
- 53:27We're working with group at Dartmouth
- 53:28that has a machine learning model.
- 53:30We have all the transcriptomic,
- 53:31We have the the slides sent from Novartis
- 53:33which is like 12 terabytes of data.
- 53:35They high,
- 53:36high resolution scanned all the slides
- 53:38from that trial and we've given them
- 53:40the micro environmental subgroups
- 53:41and strategies and they're trying to
- 53:43figure out if they can do that and
- 53:44they have already done it on the TCGS.
- 53:46So you can kind of replicate it because
- 53:48that that might be a way to to say,
- 53:49OK,
- 53:50now you've put it through an AI
- 53:52system and they say this tumor
- 53:54is this thing and this patient's
- 53:56going to recur much more or this
- 53:57patient might respond better.
- 53:58So that that's that's a strategy that I
- 54:00think a lot of us are thinking about.
- 54:02Great question for the
- 54:08community service and making
- 54:09these mouse models and thank you
- 54:11for sharing with us as well.
- 54:12I'm curious from the immuno
- 54:15oncology metabolism world,
- 54:17you know we talked a lot about the obesity
- 54:19paradox in Melanoma and lung cancer.
- 54:21Do patients with obesity respond
- 54:23better to immunotherapy.
- 54:25So I'm wondering if you know knowing that
- 54:28RCC actually is associated with obesity.
- 54:30I'm I'm wondering if you can speak
- 54:32to your mouse models if if you've
- 54:34observed any potential difference
- 54:35in the response to immunotherapy
- 54:37in in these models because it in
- 54:39mice with obesity and if not maybe
- 54:41we can collaborate that. Yeah.
- 54:42So. So it's a great question and
- 54:45something that's very near and dear.
- 54:47So.
- 54:47So I I do have funding through the DoD
- 54:49to look at obesity in kidney cancer
- 54:51and these models and we've we've
- 54:53been utilizing the transplantation
- 54:55models we so we do we did the GEM
- 54:58model first we we did fat feed them
- 55:00they're they're hard to to feed
- 55:02because of the mixed background.
- 55:04So they they gain weight not as nicely
- 55:06as if they were a clean genotype but
- 55:08we do observe earlier onset tumors
- 55:10in those in those mice but then so
- 55:12genetically when we implant them and
- 55:14that's not trivial by the way if
- 55:16you're going to do us an orthotopic
- 55:18transplantation model in a fat
- 55:20mouse because just like humans they
- 55:21develop a lot of perinephric fat.
- 55:23So if you try to open up the mouse and
- 55:25inject it it's like a **** show part
- 55:27of my French but but but essentially
- 55:30it's very challenging so so we've
- 55:32been doing but we do see that the
- 55:34tumors grow faster in obese which
- 55:36sort of makes sense because we know
- 55:39that obesity associated with with
- 55:41better development of kidney cancers
- 55:43but in it does suggest in human at
- 55:46least they seem to be less aggressive.
- 55:48So we're we're now trying to understand
- 55:50immunologically what's going on but
- 55:52I would I think we're talking soon
- 55:53so I'm happy to talk more about that
- 55:55Rachel but I think it would be a
- 55:57really it's a really cool area and
- 55:59we're we're we're focused on on Trem
- 56:012 macrophages which has been shown to
- 56:03be associated with lipid their the
- 56:05lipid associated macrophages and and
- 56:06it's associated with more aggressive tumors.
- 56:08So we can talk more about that,
- 56:10but definitely something that we're,
- 56:11we're thinking a lot about.
- 56:17All right.