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Pathology Grand Rounds, Sept. 18, 2025 - Joshua Warrick, MD

February 20, 2026

Pathology Grand Rounds, Sept. 18, 2025, Joshua Warrick, MD, professor of pathology, director, genitourinary pathology, Yale School of Medicine.

ID
13866

Transcript

  • 00:02Good afternoon. Welcome to pathology
  • 00:05ground runs.
  • 00:06And,
  • 00:08we have today's speaker, doctor
  • 00:11Joshua
  • 00:12Warwick.
  • 00:14And,
  • 00:15doctor Warwick graduated from
  • 00:19the, West Wayne State University
  • 00:21for her medical educations.
  • 00:24After that, he he did
  • 00:25his residency
  • 00:27at initially, actually, it's a
  • 00:29Lou,
  • 00:32Saint Louis or Saint Louis
  • 00:34University, Saint Litton,
  • 00:36WashU,
  • 00:37and complete his residency. And
  • 00:39then which is followed by
  • 00:41the fellowship training in Geo
  • 00:43Passage
  • 00:44as well as surgical massage
  • 00:47at University of Michigan.
  • 00:49So,
  • 00:51he joined,
  • 00:53Pennsylvania
  • 00:54State University
  • 00:56and, starting his career and,
  • 00:58risk his ranking
  • 01:00for initial assistant professor
  • 01:02to full professor.
  • 01:04So he,
  • 01:06was the
  • 01:08vice chair for clinical operation
  • 01:12and director of
  • 01:14the anatomic massage
  • 01:16and also director of the
  • 01:18GU Pathology Services
  • 01:20there.
  • 01:21We're fortunate
  • 01:22to have him,
  • 01:24you know, join the Yale
  • 01:26and he just started his
  • 01:27faculty
  • 01:29here as director of the
  • 01:31GU Passage.
  • 01:32So
  • 01:34Dodd Warrick did extensive
  • 01:37research on
  • 01:38the bladder cancers.
  • 01:40His research funding was,
  • 01:42supported by the NIH
  • 01:45and cancer
  • 01:46American Cancer Society and also
  • 01:49DODs.
  • 01:51He,
  • 01:53has been invited to give
  • 01:54many talks
  • 01:56and, at national and international,
  • 02:00conference.
  • 02:01He path bridge extensively
  • 02:03and has more than around
  • 02:05the one hundred publications
  • 02:08and peer reviewed,
  • 02:10journal articles,
  • 02:11book chapters.
  • 02:13And,
  • 02:14so today he gonna share
  • 02:16his experience
  • 02:17in the breast cancer with
  • 02:19us. His topic the the
  • 02:22title of his talk is
  • 02:23the lineage praxisity
  • 02:24of the blood cancer.
  • 02:26So without further ado, I
  • 02:28will hand over to doctor
  • 02:30Warrick. Thank you.
  • 02:35Okay. Thank you, Doctor. Kai.
  • 02:39So, yeah, so we're going
  • 02:39to talk about bladder cancer.
  • 02:42So I have I have
  • 02:43no conflicts of interest right
  • 02:44now.
  • 02:48So there's there's two themes
  • 02:49to the talk today.
  • 02:50The first is gonna be
  • 02:51that, bladder cancer demonstrates remarkable
  • 02:54lineage plasticity,
  • 02:55even without selective pressure from
  • 02:57treatment. A lot of cancer
  • 02:58types, you know, lung cancer,
  • 03:00prostate cancer, they undergo lineage
  • 03:02plasticity, but they generally require
  • 03:03treatment pressure like prostate cancer
  • 03:04and androgen deprivation therapy. Whereas
  • 03:06bladder cancer is just plastic.
  • 03:08It just does it on
  • 03:09its own.
  • 03:11And this is key, in
  • 03:12in part driven by key
  • 03:14transcription factors and interferon gamma
  • 03:16signal.
  • 03:17So these two statements are
  • 03:18are gonna really, you know,
  • 03:19like, be the frame from
  • 03:20which
  • 03:21yeah.
  • 03:21So these are the these
  • 03:23will be the the ideas
  • 03:24that we frame the entire,
  • 03:25talk through.
  • 03:29Can you guys see the
  • 03:30mouse? Good.
  • 03:31So
  • 03:32transcription factors, like so what
  • 03:34are transcription factors? Let's all
  • 03:35get on the same page
  • 03:36here. So
  • 03:37transcription factors are proteins that
  • 03:39regulate gene expression. So we
  • 03:40have about fifteen hundred of
  • 03:42these named, in the human
  • 03:44genome. And what they do
  • 03:45is they're small proteins or
  • 03:46they're proteins that bind gene
  • 03:48promoters
  • 03:49or enhancers
  • 03:50or silencers
  • 03:51to alter gene expression.
  • 03:53They they recruit, you know,
  • 03:54different proteins and stuff. But
  • 03:55by and large, what they
  • 03:56do is they bind what
  • 03:58we call cis regulatory elements
  • 04:00to
  • 04:01alter expression of a given
  • 04:02gene.
  • 04:04And these can be extremely
  • 04:05powerful in in their So,
  • 04:08this is Shinya,
  • 04:10Yamanaka. He won the Nobel
  • 04:11Prize in twenty twelve. He's
  • 04:13kind of a hero to
  • 04:14many of us.
  • 04:15So he showed something really
  • 04:17amazing,
  • 04:18that he got the Nobel
  • 04:19Prize for. He showed that
  • 04:20you could take an adult
  • 04:21dermal fibroblast,
  • 04:22add four transcription factors, and
  • 04:24turn it into an induced
  • 04:25pluripotent stem cell.
  • 04:27Those four transcription factors are
  • 04:29SOX2, WAC4, KLF4,
  • 04:31and and MYC.
  • 04:33And so him and and
  • 04:34others who worked in this
  • 04:36space kinda bulldozer an old
  • 04:37idea. The old idea was
  • 04:39this this idea of Waddington's
  • 04:40canals. This idea that that
  • 04:42embryologic tissue was,
  • 04:44was, destined to become one
  • 04:46thing, and it couldn't really
  • 04:46back up. It was like
  • 04:47once you got to a
  • 04:48certain degree of differentiation, you
  • 04:50didn't reverse it. And he
  • 04:51showed that four transcription factors
  • 04:53can reverse it, which is
  • 04:54kind of amazing. And that's
  • 04:55why I won the Nobel
  • 04:56Prize. And it it also
  • 04:57goes to show the the
  • 04:58incredible power
  • 05:00of even a few,
  • 05:02small proteins. A few transcription
  • 05:03factors can drive tremendous phenotypic
  • 05:06change,
  • 05:07in in in a cell.
  • 05:11And so one of the
  • 05:12things that, makes some a
  • 05:14subset of these transcription factors
  • 05:16so powerful
  • 05:18is they're called pioneer facts,
  • 05:20pioneer transcription factors. And so
  • 05:22as whereas many factors can
  • 05:23only bind chromatin that's opened
  • 05:25and has their their response
  • 05:26elements or the areas they
  • 05:27bind, open, pioneer factors can
  • 05:30open close chromatin.
  • 05:31And they can change the
  • 05:33the the epigenomic landscape,
  • 05:35truly
  • 05:36of of, DNA that they're
  • 05:37they're exposed to. And so
  • 05:39three of these I've named
  • 05:40because they're important in in
  • 05:41bladder cancer. So one is
  • 05:42Fox a one.
  • 05:44That's a pioneer factor that's
  • 05:45known to be important in
  • 05:46in breast cancer, for example,
  • 05:47in ER and AR binding.
  • 05:49This one's particularly well studied.
  • 05:51It it mimics a link
  • 05:52or histone. That's how it's
  • 05:53able to open up, close
  • 05:55chromatin.
  • 05:56Two other ones, GATA3 p,
  • 05:57PAR gamma, these are probably
  • 05:59also pioneer factors.
  • 06:01So these these are,
  • 06:02transcription factors, again, that can
  • 06:04bind closed chromatin fundamentally on
  • 06:06their own, change the the
  • 06:08epigenomic landscape,
  • 06:10is just a few a
  • 06:11few of these these transcription
  • 06:13factors.
  • 06:16So let's talk about bladder
  • 06:17cancer. So so bladder cancer
  • 06:19has a very well well
  • 06:21known progression.
  • 06:23Those in the urology world
  • 06:24and the the geopathology world
  • 06:25know it well.
  • 06:27Starts off as noninvasive disease,
  • 06:29like like all cancers
  • 06:30do. Either t, TIS or
  • 06:32flat carcinoma in situ or
  • 06:34TA, which is this noninvasive
  • 06:36papillary tumor. It's kinda like
  • 06:37a like a bush growing
  • 06:39on the surface or like
  • 06:39a cauliflower.
  • 06:41It invades the lamina propria.
  • 06:42That's the superficial connective tissue
  • 06:44underneath the urothelium,
  • 06:46continues to progress into the
  • 06:47the the muscular layer, the
  • 06:49muscularis propria of the bladder
  • 06:50extends outside of it, and
  • 06:52then eventually extends into other
  • 06:53organs. So we generally call
  • 06:55this non invasive tumor. We
  • 06:57call it non muscle invasive
  • 06:58if it's up to a
  • 06:59t one because it's not
  • 07:00quite in muscle. And then
  • 07:01we've got muscle invasive bladder
  • 07:02cancer whenever it's beyond that.
  • 07:04And this is used to
  • 07:05to classify,
  • 07:06you know, treatments and and
  • 07:07and breakdown,
  • 07:08you know, different prognostic tests
  • 07:11and things. So let's keep
  • 07:12this in mind as we
  • 07:13as we keep chatting about
  • 07:14the rest of the of
  • 07:14the talk.
  • 07:16And so this is the
  • 07:17histology of of most bladder
  • 07:18cancers. So this is urothelial
  • 07:20carcinoma. This is the stage
  • 07:21TA, the non invasive papillary
  • 07:23tumor that we talked about.
  • 07:24It's got these fibro vascular
  • 07:25cores. It's got these this
  • 07:27urothelial
  • 07:27thickening. There's fusion. It's really
  • 07:29just kinda confused cauliflower thing
  • 07:31growing off the surface of
  • 07:32the urothelium.
  • 07:34You've got stage TIS or
  • 07:35flat carcinoma in situ. It's
  • 07:36these malignant cells sitting on
  • 07:38the surface.
  • 07:39Then you've got invasive urothelial
  • 07:40carcinoma.
  • 07:41Kinda looks like urothelial. It's
  • 07:43not really as, you know,
  • 07:44easy to describe as a
  • 07:45lot of cancer types like
  • 07:46colon cancer and stuff. But
  • 07:48it's these jagged, you know,
  • 07:49infiltrative nests of cancer that
  • 07:50looks kinda like urothelial. And
  • 07:52this is the astrology of
  • 07:53t one. So the lamina
  • 07:54appropriate invasive stuff, and then
  • 07:56anything beyond that.
  • 08:00So we can also classify
  • 08:02bladder cancers into this, this
  • 08:03luminal versus basal,
  • 08:06dichotomy.
  • 08:07And this got a lot
  • 08:07of attention, about ten years
  • 08:09ago. And so the luminal
  • 08:11cancers tend to express, urothelial
  • 08:13genes. So FOXA one, you
  • 08:14know, get a three, PPAR
  • 08:16gamma, uroplacants.
  • 08:17They're enriched in FGFR three
  • 08:18mutations. Then there's the basal
  • 08:19cancers. Those express basal genes.
  • 08:22They're enriched in high molecular
  • 08:23weight keratins, TFAPs. They're also
  • 08:25enriched in t p TB
  • 08:26fifty three gene mutations.
  • 08:28And so there was an
  • 08:29idea about ten, eleven years
  • 08:31ago when they this this,
  • 08:32I think, first came out
  • 08:33in bladder cancer, and this
  • 08:34idea was that we have
  • 08:35intrinsic subtypes. We've identified intrinsic
  • 08:38molecular subtypes of bladder cancer,
  • 08:39and we can start tailoring
  • 08:41our treatments to these two
  • 08:42different
  • 08:43molecular subtypes. And a lot
  • 08:44of attention, a lot of
  • 08:45money, and a lot of
  • 08:46effort went into coming up
  • 08:48with ways to to treat
  • 08:49these these different molecular subtypes.
  • 08:53And I submit to you
  • 08:54that that is not the
  • 08:55case. They are not intrinsic.
  • 08:57This is not a story
  • 08:57of intrinsic molecular subtypes that
  • 08:59are born basal or born
  • 09:00luminal.
  • 09:01The story of bladder cancer,
  • 09:03the story of luminal and
  • 09:04basal is a story of
  • 09:05lineage plasticity.
  • 09:07And
  • 09:08the utility of the luminal
  • 09:10and basal is really not
  • 09:11in naming them a luminal
  • 09:12cancer or basal cancer, but
  • 09:14rather the utility is understanding
  • 09:16the drivers of luminal differentiation,
  • 09:18the drivers of basal differentiation,
  • 09:20and how we can exploit
  • 09:21those in the future
  • 09:22to treat patients with bladder
  • 09:24cancer.
  • 09:28So so here's some relevant
  • 09:29signatures whenever you break these
  • 09:31these tumors down. So,
  • 09:33what these data are are
  • 09:34from the Cancer Genome Atlas,
  • 09:36bladder cancer data, which is
  • 09:37a nice repository if you
  • 09:38wanna just look at stuff.
  • 09:41And so what we did
  • 09:42is we we took the
  • 09:43cancer genome atlas,
  • 09:45invasive bladder cancers, divided them
  • 09:46into luminal versus basal based
  • 09:48on, you know, just the
  • 09:49standard, you know, dichotomous, you
  • 09:51know, change. And then we
  • 09:52looked at single sample gene
  • 09:53set enrichment analysis scores,
  • 09:55and then compared them, in
  • 09:57these different scores. So as
  • 09:58expected, luminal cancers tend to
  • 10:00have, you know, high expression
  • 10:01of luminal genes.
  • 10:03Basal cancers tend to have
  • 10:04higher expression of basal genes.
  • 10:05This is obvious. But there's
  • 10:07some things that that pop
  • 10:08out that are
  • 10:09also of of of value.
  • 10:11One is cell cycle activity.
  • 10:12It's a little bit higher
  • 10:13in basal versus luminal. Another
  • 10:15is inflammatory signature. So this
  • 10:16is just, you know, our
  • 10:17standard hallmark inflammation
  • 10:19kinda signature.
  • 10:20And it shows that the
  • 10:21basal cancers are
  • 10:23enriched largely in in an
  • 10:25inflammatory signature.
  • 10:27And perhaps more importantly,
  • 10:29basal tumors are heavily enriched
  • 10:31at interferon gamma activity.
  • 10:33So we name them after
  • 10:34the epithelial cell that they're
  • 10:36differentiating toward more basal, more
  • 10:37squamous.
  • 10:38But whenever we break it
  • 10:40down and look at the
  • 10:41signatures, interferon gamma is extremely
  • 10:43strong in the basal squamous
  • 10:45or the basal type of
  • 10:46bladder cancer.
  • 10:51And molecular subtype also associates
  • 10:53strongly with stage.
  • 10:54And so to my mind,
  • 10:56if these were intrinsic and
  • 10:57they were either born basilar,
  • 10:58they were born luminal,
  • 11:00you would see precursors that
  • 11:02are basal. You would see
  • 11:04precursors that are luminal and
  • 11:05they would be in roughly
  • 11:06equal proportion, but that's not
  • 11:08the case at all.
  • 11:10It turns out that the
  • 11:11vast majority of non invasive
  • 11:12and even early stage invasive
  • 11:14cancers are luminal.
  • 11:15Whereas the basal nist, the
  • 11:17basal phenotype doesn't really show
  • 11:18up until you're in the
  • 11:19muscle invasive stage.
  • 11:21And so these data are,
  • 11:23combined,
  • 11:25cancer genome at least data
  • 11:26for muscle invasive tumors. And
  • 11:28then there's this large European
  • 11:29study,
  • 11:31Linsgrogg et al. They had
  • 11:32the TA and t one
  • 11:33cancers. So we the the
  • 11:35analysis we're looking at here,
  • 11:36was one of my group,
  • 11:37we we lumped the cases,
  • 11:38normalized them, and then used
  • 11:40a UNC classifier that's published
  • 11:41at University of North Carolina
  • 11:42into either luminal or basal.
  • 11:44And as expected,
  • 11:45based on some prior studies,
  • 11:46the TA were vast majority,
  • 11:48ninety five percent plus for
  • 11:49luminal.
  • 11:51Most of the t ones,
  • 11:52which is somewhat surprising, were
  • 11:53also luminal, whereas the,
  • 11:55the muscle invasive cancers, those
  • 11:57that were in the muscular
  • 11:58as appropriate or deeper were
  • 11:59about half luminal, about half
  • 12:00base. So this this to
  • 12:02me even, like, looking at
  • 12:03it says that this is
  • 12:04a a story of these
  • 12:05things changing as they develop
  • 12:06higher stage disease.
  • 12:12Okay.
  • 12:13Did I break it? There
  • 12:14we go. Okay.
  • 12:15And so, there's another piece
  • 12:17to the story in the
  • 12:18histology that really starts to
  • 12:20argue for lineage plasticity playing
  • 12:22an important role in this
  • 12:24phenotypic evolution. So,
  • 12:26in
  • 12:27bladder cancer world and the
  • 12:28residents, we talked about these
  • 12:29this morning and Tuesday morning,
  • 12:31they're probably tired of me
  • 12:32at this point.
  • 12:35So the bladder cancer has
  • 12:36many,
  • 12:37histologic variants or
  • 12:39divergent differentiation or histologic subtypes.
  • 12:40There's a bunch of ways
  • 12:41to describe these, but they're
  • 12:43named histomorphologies
  • 12:44that have specific,
  • 12:46clinical correlations and complete and
  • 12:48specific prognostic, you know, implications.
  • 12:50You know, one of those
  • 12:51is micropapillary. That's these tiny
  • 12:53little, you know, micropapillary nest
  • 12:55with attraction clefts. We've got
  • 12:56plasmacytoid that's infiltrative single cells.
  • 12:58We've got glandular, that means
  • 12:59it's it's making glands.
  • 13:01Nested, that means it's little
  • 13:02tiny blend nest that are
  • 13:03easy to to miss. Got
  • 13:04small cell that looks like
  • 13:05small cell lung cancer. You've
  • 13:06got squamous carcinoma that's making
  • 13:08keratin, not to be confused
  • 13:10with with basal or basal
  • 13:11squamous, which is usually what
  • 13:12we use to describe, you
  • 13:13know, the molecular subtypes. But
  • 13:15rather, it's histologic squamous differentiation
  • 13:17where it's making making keratin.
  • 13:19You have lymphopodeal leoma like,
  • 13:21that looks like nasopharyngeal carcinoma,
  • 13:23which is an EBV mediated
  • 13:25phenomenon with an intense inflammatory
  • 13:26infiltrate.
  • 13:27This actually isn't EBV mediated.
  • 13:29It just looks like a
  • 13:30nasopharyngeal tumor that, that is.
  • 13:33Then there's sarcomatoid,
  • 13:34which is relatively common, but
  • 13:36it's differentiating towards a sarcoma.
  • 13:38And so this is the
  • 13:40the the diversity of, you
  • 13:41know, of of bladder cancer
  • 13:43for the large part.
  • 13:46And these things tend to
  • 13:47have, consistent
  • 13:49molecular subtypes.
  • 13:51Not perfect, but there's a
  • 13:53strong tendency here. So, the
  • 13:54plasmacytoid, the micropapillary, the nested,
  • 13:56they tend to be luminal.
  • 13:59The lymphopithelium
  • 14:00alike, the squamous, histologically squamous
  • 14:02tend to be basal.
  • 14:03The sarcomatoid kinda do whatever
  • 14:05they wanna do. They're turning
  • 14:06into sarcomas, so they're a
  • 14:07little wild.
  • 14:09The glandular,
  • 14:10you know, they make glands.
  • 14:11They can be variable as
  • 14:12well.
  • 14:13You know, in neuroendocrine,
  • 14:15the small cell, they have
  • 14:16neuroendocrine phenotype, you know, they're
  • 14:17not really getting, you know,
  • 14:18you're the only one anymore.
  • 14:20And so there's, you know,
  • 14:22not only and my phone
  • 14:23is just buzzing. Hold on.
  • 14:25Spam. Do you guys get
  • 14:26spammed constantly? It's making me
  • 14:27crazy. It's, like, half ninety
  • 14:29percent of my calls.
  • 14:31Okay. So, so back to
  • 14:32this. So,
  • 14:35these histologic variants
  • 14:37strongly associate with these specific
  • 14:39molecular subtypes.
  • 14:43And so, you know, back
  • 14:45in twenty nineteen, we had
  • 14:46a study published in European
  • 14:48urology that got a lot
  • 14:49of attention.
  • 14:50Because
  • 14:51before the study came out,
  • 14:52there was this, like I
  • 14:53said, there was this
  • 14:54intense interest in intrinsicness
  • 14:57of of these molecular subtypes.
  • 14:59And there have been clinical
  • 15:00trials that were being developed,
  • 15:01putting people in these different
  • 15:02subtypes and then treating them
  • 15:03differently based on the the
  • 15:05the classifications.
  • 15:07And this study was one
  • 15:07of the first to really
  • 15:08kind of, you know, shoot
  • 15:09a hole on that idea.
  • 15:10And so what we did
  • 15:11is we took about three
  • 15:12hundred,
  • 15:14consecutive,
  • 15:15cystectomy cases. We mapped them
  • 15:16out.
  • 15:17We identified all the different
  • 15:19areas of histologically distinct invasive
  • 15:20carcinoma. We,
  • 15:22named them. We identified areas
  • 15:23of non invasive carcinoma,
  • 15:25and we performed molecular subtyping
  • 15:27on them using, the,
  • 15:30a group or a a
  • 15:31schema developed by the Lund
  • 15:32University,
  • 15:35in,
  • 15:36in in Switzerland. No. Sweden.
  • 15:38In Sweden. They would make
  • 15:39they would be angry if
  • 15:40I said they were Swiss.
  • 15:41But they're, they developed this,
  • 15:44system for for molecular classification.
  • 15:47And so they have a,
  • 15:48you know, this kind of
  • 15:49type where they call them
  • 15:50urothelial like and genomically unstable,
  • 15:51but really practically speaking, those
  • 15:53are those are luminal. They
  • 15:54have a basal squamous equivalent
  • 15:56to a basal on the
  • 15:56other systems. They have mesenchymal
  • 15:58like that is really rare,
  • 15:59kind of like sarcoma, and
  • 16:00then they have non type.
  • 16:01What we did is we
  • 16:02performed molecular subtyping on all
  • 16:04the different areas from these
  • 16:05bladders that we mapped out.
  • 16:07And this is how we
  • 16:08demonstrated those that had,
  • 16:10you know, histologic diversity.
  • 16:12And so each column is
  • 16:14a histology, we've got conventional
  • 16:15urothelial, squamous, micropapillary, glandular, etcetera.
  • 16:18Each row is a patient,
  • 16:20and then each color is
  • 16:22a a molecular subtype.
  • 16:24So what we we see
  • 16:25here is that if we
  • 16:27go along each row, we
  • 16:28can see the different histologies
  • 16:29each patient had. Gray means
  • 16:31they didn't have it. Then
  • 16:32we can see what molecular
  • 16:33subtype they were assigned to.
  • 16:35And what we can see
  • 16:35here is that there's diversity.
  • 16:37They're not all the same.
  • 16:39They're not intrinsic.
  • 16:40They differ. So for example,
  • 16:42this first row of the
  • 16:43conventional urothelial was a luminal
  • 16:45subtype and associated histologically squamous
  • 16:47was basal squamous.
  • 16:49Same thing with these guys.
  • 16:51Here, this was also luminal.
  • 16:52These are basal squamous. The
  • 16:53conventional was urothelial. The histologically
  • 16:56squamous was a basal subtype.
  • 16:58And then it gets even
  • 16:58more interesting. Some have, you
  • 17:00know, like
  • 17:01a, you know, basal conventional
  • 17:03urothelial, basal squamous, then there's
  • 17:04a micropapillary in a different
  • 17:05area that was luminal.
  • 17:07So this
  • 17:08really is one of the
  • 17:09first indications that, like, no.
  • 17:10These things are not just
  • 17:11born one way and they
  • 17:13stay that way. There's plasticity
  • 17:14going on. These are changing
  • 17:15as they evolve from different
  • 17:17to different,
  • 17:18histologies.
  • 17:19And in fact, thirty nine
  • 17:20percent of cases
  • 17:22in which there was histologic
  • 17:23diversity also demonstrated a difference
  • 17:25in molecular subtype, and it's
  • 17:27extremely common in those that
  • 17:28had a basal squamous component.
  • 17:30There was even one basal
  • 17:31squamous component. Nearly eighty percent
  • 17:33had another area that was
  • 17:34luminal.
  • 17:35It could have been the
  • 17:36non invasive component, could have
  • 17:37been another, but it really
  • 17:38demonstrated that there's a a
  • 17:39tremendous amount of,
  • 17:41diversity in terms of the
  • 17:42luminal versus basal,
  • 17:44dichotomy in these things.
  • 17:46And so that led to
  • 17:47a different framework than they're
  • 17:48born luminal or they're born
  • 17:50basal, but rather they're mostly,
  • 17:51if not all born, luminal.
  • 17:53And certainly we can't be
  • 17:54absolute here. This is
  • 17:56this is cancer. It kind
  • 17:56of does what it wants.
  • 17:57We've seen squamous displays in
  • 17:59the bladder, but by and
  • 18:00large,
  • 18:01most of these things start
  • 18:02off, we think is not
  • 18:03invasive. You're of the ileal
  • 18:04carcinoma that's luminal. It invades
  • 18:06like we see with the
  • 18:07t one cancers that are
  • 18:08luminal And early on, it's
  • 18:10the invasive cancers also luminal.
  • 18:11And then from there, it
  • 18:13it undergoes lineage plasticity
  • 18:15to a basal subtype.
  • 18:16And those can turn into
  • 18:17histologic,
  • 18:19basal variance. And then the
  • 18:20urothelial conventional can turn into
  • 18:22invasive histologic luminal,
  • 18:24variance.
  • 18:25So this is the framework
  • 18:26that we're working from now.
  • 18:27And so,
  • 18:29you know, the one of
  • 18:30the questions as well, how
  • 18:31do you know that it's
  • 18:32not just, like, you know,
  • 18:33collision tumors? Why aren't the
  • 18:34why were the luminal micropapularies
  • 18:36and the histologically squamous basal
  • 18:38ones? Are they two separate
  • 18:39tumors
  • 18:40that just collided? And it's
  • 18:42just a coincidence, and I
  • 18:43think the answer is no.
  • 18:44And we we answered that
  • 18:46with, the paper, in nature
  • 18:47communications a few years back.
  • 18:49This was a collaboration with,
  • 18:52Memorial Sloan Kettering, Hikma Del
  • 18:53Amadi, and,
  • 18:54Wenohu,
  • 18:55were two of the main
  • 18:56collaborators there. And so what
  • 18:58we did in in this
  • 18:59study is we,
  • 19:01gathered
  • 19:02a number of patients, twelve
  • 19:04in total, who had invasive
  • 19:06urothelial carcinomas with a clearly
  • 19:08conventional urothelial carcinoma component
  • 19:10and a clearly squamous invasive
  • 19:12squamous carcinoma component. And we
  • 19:14did,
  • 19:16you know, comprehensive genomic evaluation
  • 19:18on them or at least
  • 19:19what was called comprehensive at
  • 19:20the time. So we did,
  • 19:21whole exome sequencing. We did
  • 19:23RNA sequencing.
  • 19:25We did this on a
  • 19:25lot more than twelve, but
  • 19:26the we only kept the
  • 19:28twelve that had high quality
  • 19:29RNA. It's difficult to get
  • 19:30high quality RNA out of
  • 19:31tissue blocks.
  • 19:33So we we performed RNA
  • 19:35sequencing,
  • 19:35sequencing.
  • 19:37And then we we, you
  • 19:38know, saw the results. And
  • 19:39this is the first thing
  • 19:40we saw
  • 19:42was the the the pair
  • 19:43urothelial carcinomas and squamous carcinomas,
  • 19:46were clonally related, but subclonally
  • 19:48distinct.
  • 19:49And so they were all,
  • 19:50all twelve of them had
  • 19:52multiple,
  • 19:54cancer driver genes that were
  • 19:55identical between the two different
  • 19:56histologies. So for example, we've
  • 19:58got, you know, we're demonstrating
  • 19:59here, we've got the urothelial
  • 20:00component, the squamous component
  • 20:02Here, we've got,
  • 20:05you know, like, the common
  • 20:06precursor presumed common precursor.
  • 20:08Here's the common mutations between
  • 20:10the two. Here's common or
  • 20:12here's mutations exclusive to the
  • 20:13squamous component. Here's, mutations unique
  • 20:16to the erythema component. And
  • 20:17so these are just three
  • 20:18example cases.
  • 20:20So in this one, they're
  • 20:22identical.
  • 20:23You know, cancer driver mutations
  • 20:25in Fgfr3, TP53, PIK3CA, and
  • 20:27then thirty one more that
  • 20:28were common to both. They
  • 20:29were unique mutations in both
  • 20:31the squamous and urothelial components.
  • 20:33Same with this one, also
  • 20:34f g f r three
  • 20:35mutations. And remember, f g
  • 20:36f r three is more
  • 20:37associated with luminal cancer, and
  • 20:38these developed histologically squamous disease.
  • 20:40So
  • 20:41this is really screaming lineage
  • 20:43plasticity to my mind. So
  • 20:44you've got f g f
  • 20:45r three, you've got ATM,
  • 20:47we've got PIK3CA.
  • 20:48Again, there's some unique mutations
  • 20:50in the squamous component including
  • 20:51TP53.
  • 20:53And then the same with
  • 20:53this one, it's not an
  • 20:54FGFR3 mutant cancer, but it's
  • 20:57got,
  • 20:58multiple
  • 20:59known cancer driver genes between
  • 21:01both the urothelial component and
  • 21:03the paired histologically squamous component.
  • 21:05Really, I think
  • 21:07proving that these things iterize
  • 21:09from a common precursor despite
  • 21:10their distinct
  • 21:11histology.
  • 21:15So what about, your molecular
  • 21:17subtype, this luminal versus bathel
  • 21:20dichotomy? So we have the
  • 21:21RNA Seq data. We only
  • 21:22selected cases that had, you
  • 21:24know, high quality RNA sequencing
  • 21:25data.
  • 21:26Anew did a few things.
  • 21:28First, we put them into
  • 21:29categorical,
  • 21:30luminal versus basal subtypes
  • 21:32based on the TCGA system
  • 21:34and and centroid analysis. So
  • 21:35that's shown here.
  • 21:37Each column is a patient.
  • 21:39Each row is a histology.
  • 21:40So this is the urothelial
  • 21:41part. This is the squamous
  • 21:43part. The color is the
  • 21:44subtype.
  • 21:45So that's kinda orange salmon
  • 21:47color is basal.
  • 21:48Then the blue and the
  • 21:49green are both luminol subtypes.
  • 21:51There are a lot of
  • 21:51different systems. The TCGA has
  • 21:53one that's subclassified as liminal,
  • 21:54but we'll pull them, for
  • 21:56the sake of, you know,
  • 21:56simplicity in the discussion.
  • 21:58And four of the twelve,
  • 22:01switched subtype,
  • 22:02whenever we use the centroid
  • 22:03analysis.
  • 22:04So using the subtype as
  • 22:06a categorical variable centroid analysis,
  • 22:09we saw that, you know,
  • 22:10a third of them were
  • 22:11different between the two. This
  • 22:12is consistent with what we
  • 22:13found earlier.
  • 22:15And and
  • 22:16I think more interestingly, we
  • 22:17found that it it it
  • 22:19was went beyond that. So,
  • 22:22we performed, you know, single
  • 22:24sample gene set of enrichment
  • 22:25analysis with gene lists of
  • 22:26basal genes and and luminal
  • 22:28genes to give a quantified
  • 22:29or quantitative score of baseness
  • 22:32and luminous.
  • 22:34In every single case, the
  • 22:35squamous component had a higher
  • 22:37basal score than the luminal
  • 22:39than the urothelial component.
  • 22:41And in every single case,
  • 22:42the squamous component had a
  • 22:43lower luminal score than the
  • 22:45urothelial component.
  • 22:47Really showing that this it
  • 22:49it's really, I think, putting
  • 22:50more and more cracks in
  • 22:51this idea of luminal versus
  • 22:52basal dichotomy. That that we
  • 22:54we have not only that
  • 22:55a third of them change
  • 22:57subtype,
  • 22:58but that all of them
  • 22:59are more basal, and all
  • 23:00of them are less liminal.
  • 23:02So this is looking more
  • 23:03like a continuous variable than
  • 23:04it is like a categorical
  • 23:05variable.
  • 23:08How about, you know, we
  • 23:09talked about that,
  • 23:11immunity,
  • 23:12before.
  • 23:13We talked about how they're
  • 23:14the interferon gamma,
  • 23:17and just looking at these
  • 23:18subtypes is higher in the
  • 23:19basal subtype, and it's pretty
  • 23:20significantly higher. So what about
  • 23:22immune
  • 23:24subtype,
  • 23:25between the urothelial and the
  • 23:26histologically squamous components?
  • 23:28So, we handle this in
  • 23:30a few ways. One of
  • 23:31them is we assign them
  • 23:33what was called an immune
  • 23:34subtype. So this group, you
  • 23:35know, Thorson et al published
  • 23:37a nice paper in immunity
  • 23:38in twenty eighteen,
  • 23:39that I found is really
  • 23:40useful where they assigned six
  • 23:41different inflammatory
  • 23:43subtypes,
  • 23:44to cancers, you know, based
  • 23:46on on, you know, the
  • 23:47TCGA data.
  • 23:48They named them c one
  • 23:49to c six.
  • 23:51C two is an interferon
  • 23:52gamma dominant
  • 23:53in, inflammatory subtype. And then
  • 23:56there's a number of other
  • 23:56ones. C one's wound healing.
  • 23:58C three is inflamed.
  • 23:59They have a number of
  • 24:00other named ones.
  • 24:01And so we used our
  • 24:03RNA sequencing data to put
  • 24:04the the tumors into,
  • 24:07these thorasin immune subtypes.
  • 24:09And not surprisingly, we found
  • 24:10all the histologically squamous areas,
  • 24:13where the c two interferon
  • 24:15gamma dominant
  • 24:17subtype. We similarly found that,
  • 24:20nine of the twelve,
  • 24:21urothelials were also, you know,
  • 24:23the c two interferon,
  • 24:25dominant, but three of them
  • 24:26were not. So there was
  • 24:27some heterogeneity,
  • 24:29in the immune subtype
  • 24:31in in these tumors.
  • 24:33PDL one also differed. And
  • 24:34so,
  • 24:36PDL one is a a
  • 24:37target of interferon gamma. So
  • 24:39interferon
  • 24:40gamma signaling induces higher PDL
  • 24:42one expression. This is pretty
  • 24:43well well known. And the
  • 24:44squamous component on average had
  • 24:46higher PDL1 expression of the
  • 24:47urothelial.
  • 24:49So
  • 24:50not only are they histologically
  • 24:52different,
  • 24:53and they're different in their
  • 24:54immune sub their their molecular
  • 24:55subject, their immune subtype seems
  • 24:56to be different as well.
  • 24:58So So this lineage plasticity
  • 24:59is taking on a kind
  • 25:00of a life of its
  • 25:01own.
  • 25:04And so what does it
  • 25:05matter at this point? Right?
  • 25:07That's always the question I
  • 25:08like to ask myself. Why
  • 25:09is this important?
  • 25:10And so,
  • 25:12Hikmat Elhamdi,
  • 25:13from Sloan Kettering, he's a
  • 25:14pathologist out there. So he
  • 25:16was part of, one of
  • 25:17the clinical trials that looked
  • 25:19at at atezolizumab
  • 25:20in metastatic and locally invasive
  • 25:22bladder cancer.
  • 25:23And so he was one
  • 25:24of the guys who reviewed
  • 25:25the slides and confirmed its
  • 25:26bladder cancer and all that
  • 25:27kind of stuff. And so
  • 25:29he he he had an
  • 25:30idea. He's like, alright. So
  • 25:31we see this immune heterogeneity
  • 25:33in our tumors. So I'm
  • 25:35gonna
  • 25:36grab the the tumors from
  • 25:37Sloan Kettering that were part
  • 25:38of this this clinical trial.
  • 25:40I'm just gonna look at
  • 25:41them blinded, and I'm gonna
  • 25:42break down, is there histologic
  • 25:44heterogeneity or not? Or is
  • 25:46there morphologic heterogeneity?
  • 25:47And he defined this precisely.
  • 25:49He said, is it a
  • 25:50named are there more than
  • 25:51one named histology
  • 25:53in this in this tumor?
  • 25:55Yes or no? Just kinda,
  • 25:56you know, made us hash
  • 25:57marks. And then we did
  • 25:58the statistics in terms of,
  • 26:01response or no response.
  • 26:03And it turned out those
  • 26:04with,
  • 26:05morphologic heterogeneity
  • 26:08were enriched in the non
  • 26:09responder group.
  • 26:11Whereas those who
  • 26:13lacked morphologic heterogeneity
  • 26:15were enriched in the responder
  • 26:17group. Certainly a small n,
  • 26:18but it was significant and
  • 26:19it was it was impressive.
  • 26:21And so one of the
  • 26:22thoughts here is that maybe
  • 26:24we know there's this immune
  • 26:26heterogeneity or we've seen this
  • 26:27immune heterogeneity.
  • 26:29Are these tumors with immune
  • 26:30heterogeneity in spatially distinct areas
  • 26:32better able to adapt
  • 26:34to immune checkpoint inhibitor because
  • 26:35they have
  • 26:37this greater diversity to
  • 26:39get around it. And so
  • 26:41this is likely clinically important.
  • 26:44So what about the experimental
  • 26:46data?
  • 26:46You know, this is all
  • 26:47observational. You know, we've we're
  • 26:49looking at human tumors. This
  • 26:50is really pointing at,
  • 26:52lineage plasticity as being being
  • 26:53important here.
  • 26:57Being the driver of, you
  • 26:58know, the luminal versus basal
  • 27:00dichotomy.
  • 27:01What about experimental data? So
  • 27:04I'll give it away, the
  • 27:05experimental data is pretty good
  • 27:07and we I think we've
  • 27:08identified some main drivers
  • 27:10of both luminal differentiation
  • 27:12and of basal differentiation. And
  • 27:14I think the luminal differentiation
  • 27:16is driven by a few
  • 27:17transcription factors and basal
  • 27:19differentiation appears driven heavily by
  • 27:21interferon gamma signaling. So I'll
  • 27:23tell you the evidence we've
  • 27:24got right now. So this
  • 27:25is an older paper, we
  • 27:26published twenty sixteen,
  • 27:29where we,
  • 27:31asked the question, can we
  • 27:32change the molecular subtype
  • 27:34of bladder cancer cell lines?
  • 27:36So what we did is
  • 27:37we,
  • 27:39took the cancer cell line
  • 27:40encyclopedia data, which is, you
  • 27:41know, publicly available expression data
  • 27:43for cell lines. We put
  • 27:44them into two categories, either
  • 27:45basal cell lines, luminous or
  • 27:47luminal cell lines. We threw
  • 27:48away a bunch of them
  • 27:49because they didn't really, you
  • 27:50know, have the expression pattern
  • 27:51of either.
  • 27:53Then we picked one of
  • 27:53the basal cell lines, five
  • 27:55six three seven. This is
  • 27:57the CCLE one. This is
  • 27:58ours.
  • 27:59And we
  • 28:01saw if we could push
  • 28:02it from basal to luminal
  • 28:03using transient transfection with,
  • 28:07Foxy one, get a three,
  • 28:08and then use rosaglitazone
  • 28:10to is a PPAR gamma
  • 28:12agonist to see if activation
  • 28:13of these three transcription factors
  • 28:15could push
  • 28:16it. And and they did,
  • 28:17and they impressively so. So
  • 28:19here's our,
  • 28:21five six three seven controls.
  • 28:23This is FOXA one alone.
  • 28:25This is got a three
  • 28:25alone. This is FOXA one
  • 28:26and got a three. Together
  • 28:27you kinda get the picture.
  • 28:29This is a centroid plot,
  • 28:30so this is a basal
  • 28:31centroid correlation.
  • 28:33The higher it is, the
  • 28:34more basal,
  • 28:35the cell line is. Here's
  • 28:37the luminal centroid correlation, the
  • 28:38higher it is, the more
  • 28:39luminal,
  • 28:40the cell line is. And
  • 28:42as we add more transcription
  • 28:43factors, we we push them
  • 28:45more in the liminal direction.
  • 28:47To the point where when
  • 28:47we've added all three transcription
  • 28:49factors,
  • 28:50we consistently, and at least
  • 28:51two replicates, and this is
  • 28:52we've seen beyond this, we
  • 28:54push them to a a
  • 28:55luminal phenotype.
  • 28:56And
  • 28:58so, go back to Yamanaka
  • 28:59factors, we can turn a
  • 29:00fibroblast
  • 29:01into an induced pluripotent stem
  • 29:03cell with four transcription factors.
  • 29:05It looks like we can
  • 29:06turn a bladder cancer cell
  • 29:07line from a basal type
  • 29:08to a luminal
  • 29:10type with three.
  • 29:16And so what are the
  • 29:17opposite direction?
  • 29:18So
  • 29:19the next thought is we
  • 29:20FOXA1 seems like the best
  • 29:22established. We knew more about
  • 29:23FOXA1
  • 29:24than any of these other
  • 29:25factors.
  • 29:27So we're like, what happens
  • 29:28if we knock out FOXA1?
  • 29:29So we knocked out FOXA1
  • 29:31in a couple of luminal
  • 29:31cell lines,
  • 29:33and it doesn't just turn
  • 29:34into basal.
  • 29:35It doesn't just you know,
  • 29:36you knock out FOXA1, they
  • 29:37become basal. That doesn't happen
  • 29:38at all. There's buffering in
  • 29:40there.
  • 29:41Just kinda like they're not
  • 29:42even that much more more
  • 29:43basal really when you knock
  • 29:44out Fox a one. And
  • 29:45we've done this with visa
  • 29:46lines,
  • 29:47but something else does happen.
  • 29:49That's kinda telling, kinda fascinating
  • 29:51and probably important.
  • 29:53And I think it comes
  • 29:54to, you know, what I
  • 29:55was saying earlier about,
  • 29:57molecular subtypes being not as
  • 30:00important as a categorical things.
  • 30:01We put things in and
  • 30:02treat people differently, but giving
  • 30:04us an understanding and insight
  • 30:06into where the Achilles
  • 30:07heels
  • 30:08in bladder cancer. What are
  • 30:10the super important
  • 30:11little triggers that we can
  • 30:12we can work with? And
  • 30:13I think Fox a one
  • 30:14is one of them. And
  • 30:15I think
  • 30:16that one of the pieces
  • 30:18of data we have that
  • 30:18is if you knock out
  • 30:19Fox a one in a
  • 30:21luminal cell line, it doesn't
  • 30:22become basal,
  • 30:24but it turns up interfering
  • 30:26gamma signal,
  • 30:28which is kinda weird. So
  • 30:30like these are cell lines,
  • 30:31these are not CD eight
  • 30:32cells.
  • 30:33These these are just epithelial
  • 30:34cells,
  • 30:36but the the basal cell
  • 30:37lines tend to over express,
  • 30:40interferon gammas even though they're
  • 30:41just cell lines, whereas the
  • 30:42luminal ones have lower expression.
  • 30:44But if you take a
  • 30:44luminal one, you knock out
  • 30:46FOXA1, you turn up interferon
  • 30:48gamma signaling, you don't do
  • 30:49it subtly.
  • 30:51So here's the here's the
  • 30:52data for that. So,
  • 30:53here we used the UMEC
  • 30:55one,
  • 30:56luminal cell line.
  • 30:58There's this is our expression
  • 30:59data from RNA sequencing,
  • 31:01ROSA genes. These are some,
  • 31:02what are called the interferon
  • 31:04response genes.
  • 31:05Blue is higher, red is
  • 31:06lower. Wen Ho did that.
  • 31:07Blame him. He's one of
  • 31:08our collaborators. I wish we
  • 31:09did on the opposite.
  • 31:11But what it showed is
  • 31:12that on our knockouts, we
  • 31:13see this substantial increase in,
  • 31:16expression of interferon
  • 31:18responsive genes in our knockouts.
  • 31:20And and we saw the
  • 31:21same with interferon alpha signaling,
  • 31:22interferon gamma signaling using, you
  • 31:24know, standard GSEA.
  • 31:26We also saw that when
  • 31:27we knocked out FOXA1 PDL1
  • 31:29expression went up, which we
  • 31:30know is a a downstream,
  • 31:31you know, product of interferon
  • 31:33gamma signaling.
  • 31:34So so this is, I
  • 31:35I think, a potentially important
  • 31:37thing, and we're digging into
  • 31:38this a lot. We talked
  • 31:38a little bit about this
  • 31:39on on Tuesday at the,
  • 31:41the the rip talk. But,
  • 31:43this is, I think, an
  • 31:44important thing
  • 31:45in developing, you know, customized
  • 31:46treatments for for, for bladder
  • 31:49cancer. And we're we're continuing
  • 31:50to work on on what
  • 31:51this means.
  • 31:54And it, you know, raises
  • 31:55another question too. So, okay,
  • 31:56we this is this is
  • 31:57kind of strange. We knock
  • 31:58out FOXA1
  • 31:59in epithelial cancer cell lines.
  • 32:02We drive interferon gamma signaling
  • 32:04even though there's no inflammatory
  • 32:05cells to be found.
  • 32:07And we know that
  • 32:08if through through some other
  • 32:09data that, you know, basal
  • 32:11squamous bladder cancers not only
  • 32:12have higher interferon gamma signaling,
  • 32:14but they're inflamed. There are
  • 32:15more, you know, immune cells
  • 32:16in them.
  • 32:18How's it getting there? And
  • 32:19the question arose, like, does
  • 32:20what does interferon gamma do
  • 32:23to luminal cell lines? So
  • 32:25we know if we knock
  • 32:25out FOXA1 in the luminal
  • 32:27cell line, we turn into
  • 32:28a basal cell line. What
  • 32:29if we take a liminal
  • 32:30cell line, we treat it
  • 32:31with interferon gamma, what happens?
  • 32:33And it turns out they
  • 32:34turn basal
  • 32:36or they get more basal
  • 32:37at least. So what we
  • 32:38did, here's three, liminal cell
  • 32:40lines, r t one one
  • 32:41two,
  • 32:44SW seven eighty.
  • 32:46These are our genes. These
  • 32:47are our luminal genes. These
  • 32:49are our basal genes.
  • 32:51And so you can see
  • 32:52here that, you know, with
  • 32:53the knockouts, these are the
  • 32:54knockouts here, these are the
  • 32:55wild types. We see this
  • 32:57increased expression
  • 32:58in basal genes consistently. I
  • 33:00mean, sorry. These are the,
  • 33:01these are interferon gamma treated.
  • 33:03I apologize. So control interferon
  • 33:05gamma treated. You see this
  • 33:06increased expression
  • 33:08of the the basal genes,
  • 33:10including the molecular the, you
  • 33:12know, keratin six, you know,
  • 33:13keratin fourteen, these high molecular
  • 33:15weight keratin. It's not just
  • 33:16the inflammatory things. It's the
  • 33:17epithelial things as well that
  • 33:19are going up.
  • 33:21And so we also, you
  • 33:23know, looked at centroid analysis
  • 33:24similar to we did in
  • 33:25that that,
  • 33:26study where we turned luminal
  • 33:28cell lines into basal cell
  • 33:29lines.
  • 33:30So here's control, here's interferon
  • 33:32gamma treatment.
  • 33:33This is showing the correlation
  • 33:34of the basal centroid. So
  • 33:36that means with centroid analysis,
  • 33:38our sequencing data, the higher
  • 33:39it is, the the more
  • 33:41the more basalts becoming, the
  • 33:42closer it's getting to that
  • 33:43basal centroid.
  • 33:46And so with each one
  • 33:47of them, they got a
  • 33:47little they got closer to
  • 33:48that basal centroid and two
  • 33:49of the threes flipped flipped.
  • 33:51Meaning, they got closer to
  • 33:53the basal centroid than the
  • 33:54they were to the luminal
  • 33:55centroid. And those two were,
  • 33:57UMBC one and RT one
  • 33:59one two, whereas the SW
  • 34:00seven eighty cell line didn't
  • 34:01flip, but it just got
  • 34:02closer.
  • 34:04And similarly,
  • 34:06you know, the interferon dominant,
  • 34:07we also put these in
  • 34:08the inflammatory
  • 34:09thoresen subtypes. And, you know,
  • 34:10totally as you'd expect they'd
  • 34:12be. They got much much
  • 34:13more of this interferon gamma
  • 34:14dominant,
  • 34:15subtype.
  • 34:16So that was interesting. So
  • 34:17interferon gamma appeared to be
  • 34:19driving the basal. It wasn't
  • 34:20just that if you knock
  • 34:21out FOXA1, it becomes more
  • 34:22interferon gamma dominant. There's there's
  • 34:24a loop here. There's some
  • 34:25kind of a feedback mechanism
  • 34:27going on.
  • 34:29Then we thought, well, maybe
  • 34:30we could do the opposite.
  • 34:32So,
  • 34:33what if we take basal
  • 34:34cell lines and we inhibit
  • 34:36interferon gamma signaling?
  • 34:38So we did, we took,
  • 34:40the basal cell line stabber,
  • 34:42which is a well established
  • 34:43bladder cancer basal cell line,
  • 34:45and we treated it with
  • 34:46the the JAK inhibitor ruxolitinib.
  • 34:48Ruxolitinib is it's a relatively
  • 34:50new drug. It's used to
  • 34:51treat myelofibrosis,
  • 34:52a couple other heme diseases.
  • 34:54It's a pan JAK inhibitor
  • 34:56and it's JAK one and
  • 34:56JAK two, and those are
  • 34:58the receptor tyrosine kinases that
  • 34:59carry out interfering gamma signaling.
  • 35:02So we can treat it
  • 35:03as an interfering gamma inhibitor.
  • 35:05And so whenever we treated
  • 35:06the basal cell lines GABA
  • 35:07with the JAK inhibitor,
  • 35:09it didn't flip all the
  • 35:10way to luminol, but it
  • 35:12became more luminol.
  • 35:13So it it lowered expression
  • 35:15of basal genes and it
  • 35:16increased expression of of, luminal
  • 35:18genes. So we've got here
  • 35:19is our ruxolitinib treated group,
  • 35:22our,
  • 35:23control group. Here are our
  • 35:25genes. Here are our basal
  • 35:26genes. Here are our luminal
  • 35:27genes. And you can see
  • 35:29that whenever you're treated with
  • 35:30ruxolitinib,
  • 35:32the ex
  • 35:33expression of the
  • 35:35the the luminal genes went
  • 35:36up pretty substantially.
  • 35:38Not only to flip it
  • 35:39because these SCABER cell lines,
  • 35:41they're whenever you grow these
  • 35:42things in xenografts, they're making
  • 35:43keratin. They are very, very
  • 35:45basal bladder cancers. Even those,
  • 35:47we are able to to
  • 35:48push more in in the
  • 35:50luminal direction with ruxolitinib.
  • 35:53And you'll notice among these
  • 35:54luminal genes, FOXA1 went up,
  • 35:57GATA3 went up, and PPAR
  • 35:58gamma largely went up. And
  • 36:00you'll recall those are the
  • 36:01three that we used to
  • 36:03drive the basal cell line
  • 36:05to a liminal liminal type.
  • 36:08And, you know, as expected,
  • 36:09we we also looked at
  • 36:11this, these these inflammatory
  • 36:13subtypes, the thoras and ones,
  • 36:14and we really diminished the
  • 36:16the the, probability of a
  • 36:18interferon gamma, you know, inflammatory
  • 36:20subtype.
  • 36:25So, so in summary,
  • 36:27you know, I think that
  • 36:29with the evidence we've collected,
  • 36:30you know, bladder cancer is
  • 36:32phenotypically diverse, we can know
  • 36:33this, and it's likely a
  • 36:35result of lineage plasticity. It's
  • 36:36not that they're just born
  • 36:37one way or the other.
  • 36:38It's a plastic process that
  • 36:39starts off probably from stuff
  • 36:41that's differentiated toward urothelium.
  • 36:44And then that lineage plasticity
  • 36:45toward the basal phenotype appears
  • 36:46driven by interferons
  • 36:48or interferon gamma, whereas,
  • 36:50differentiation toward the liminal phenotype
  • 36:52appears to be driven by
  • 36:53by these these key transcription
  • 36:55factors.
  • 36:57And that is all I
  • 36:58have to say.
  • 36:59Thank you. Happy to take
  • 37:01questions.
  • 37:09Yeah. Go ahead. I have
  • 37:11two questions. Yes.
  • 37:29Yes. No. So it was
  • 37:31it's just kind of a
  • 37:31theoretical,
  • 37:32you know, precursor, so I
  • 37:34can I can go back?
  • 37:38Yeah. So it was like
  • 37:41Yes. Yeah. So this one.
  • 37:42So,
  • 37:43you know, we we sequence
  • 37:44both. These are part of
  • 37:45the same tumor. So think
  • 37:46of this as a tumor.
  • 37:47You know, one area squamous,
  • 37:48one area is epithelial.
  • 37:50And so spatially distinct parts
  • 37:51of the same physical mass,
  • 37:54and we sequenced them. And
  • 37:55so this dot here indicates,
  • 37:58the the common precursor. You
  • 38:00know, think of this like
  • 38:01an evolutionary phylogeny.
  • 38:03This would be the the
  • 38:04the common ancestor of the
  • 38:05two, and we can say
  • 38:06it's the common ancestor because
  • 38:07it shares the key driver
  • 38:08mutations. And then this thing
  • 38:10is, we just added that
  • 38:11so you'd have, like, you
  • 38:12know, some idea of, like,
  • 38:13you know, the cell from
  • 38:14which they both arose. It's
  • 38:15more like eye candy. It
  • 38:16really doesn't, you know, add
  • 38:18much to the meaning of
  • 38:19the figure.
  • 38:33So this this was the
  • 38:34biopsy. So those were, either
  • 38:36metastatic or locally advanced, urothelial
  • 38:39carcinoma that that we were
  • 38:40looking at. So these would
  • 38:41have been biopsies from
  • 38:43it it they weren't super
  • 38:45strict in terms of the
  • 38:46histology that was required,
  • 38:48but it was just some
  • 38:49kind of biopsy demonstrating that
  • 38:50was either locally advanced or
  • 38:52or a metastatic disease.
  • 38:54And you can't file with
  • 38:55the GHAH and E even
  • 38:57for our own Even from
  • 38:58that. Yep.
  • 39:04Anyone else?
  • 39:06Excellent.
  • 39:07Okay.
  • 39:09So I have a question
  • 39:09about your diagram.
  • 39:19There is, but you you
  • 39:20gotta draw the line somewhere.
  • 39:23Yeah. So it's
  • 39:24we we just pick these
  • 39:25as kinda like to illustrate
  • 39:26because their genes that that
  • 39:27are important or are well
  • 39:29known.
  • 39:30But it was it's kind
  • 39:31of amazing. Like, some of
  • 39:32these cases, they were they
  • 39:33were more different than they
  • 39:34were similar.
  • 39:36In some cases, they were
  • 39:37more similar than they were
  • 39:37different. But, yeah, we just
  • 39:39kinda had to, you know,
  • 39:39start somewhere, so that's why
  • 39:41we we limited it. It's
  • 39:42easy to find the current
  • 39:44Mhmm. And then being on
  • 39:45as one week.
  • 39:51Yeah. Yeah. I mean and,
  • 39:51well, I think, you know,
  • 39:52it it
  • 39:53possibly informing new biology.
  • 39:56Because, you know, like, for
  • 39:57example, this one, the TP
  • 39:58fifty three, gene mutation was
  • 40:00was private to the squamous
  • 40:01part. And, you know, squamous
  • 40:03is thought to be more
  • 40:03aggressive, and I guess that
  • 40:04makes sense.
  • 40:06But, you know, in this
  • 40:06one, the TP fifty three
  • 40:08gene mutation and in this
  • 40:09one, it was it was
  • 40:10common to both. So it's
  • 40:11it's really hard. I I
  • 40:12think one of the things
  • 40:13we've learned from the past
  • 40:14ten years is that it's
  • 40:15very hard to identify, you
  • 40:17know, key driver mutations
  • 40:19that are responsible
  • 40:20or relate to squamous histology.
  • 40:22It really seems to be
  • 40:23more of a, you know,
  • 40:24a transcriptional
  • 40:25process than it is a
  • 40:26mutation driven process, if you
  • 40:28will.
  • 40:31So I have a question.
  • 40:33You know, why we we
  • 40:35validate
  • 40:36that
  • 41:31Yeah. So it's it's a
  • 41:32great question and much,
  • 41:34there's been a lot of
  • 41:34conversation about this in the
  • 41:35bladder cancer world, a lot
  • 41:37of lot of ink spilled
  • 41:38or, you know, virtual ink
  • 41:39spilled out on the topic.
  • 41:40And so,
  • 41:42one of the things that's
  • 41:43popped out is that
  • 41:45it's very difficult to create
  • 41:47reliable
  • 41:48categorical
  • 41:49tests
  • 41:50for basal versus luminal.
  • 41:52And I think it relates
  • 41:53to, you know, us showing
  • 41:54this as a, a it's
  • 41:56not a categorical variable. Truly,
  • 41:57it's a it's a continuous
  • 41:59variable. And so I think
  • 42:00one of the the best
  • 42:01stories well, not best stories,
  • 42:02but one of the most
  • 42:03telling stories,
  • 42:04is with the DECIPHER bladder
  • 42:06cancer test. So decipher bladder
  • 42:08cancer test was something that
  • 42:09was, marketed,
  • 42:12I believe it was even
  • 42:13FDA approved.
  • 42:14I don't remember. I have
  • 42:15to look that up, but
  • 42:16it was marketed,
  • 42:17to to assign molecular subtypes
  • 42:19to muscle invasive bladder cancer
  • 42:21to to decide if it's
  • 42:23going to be,
  • 42:24responsive to neoadjuvant cisplatin based
  • 42:26chemotherapy, which is the standard.
  • 42:28And they showed that,
  • 42:31the their their basal subtype
  • 42:33had better response than their
  • 42:34non basal sub subtype. So
  • 42:36they were they were advocating
  • 42:37using this to make this
  • 42:38key clinical decision, and that
  • 42:40was the decipher group.
  • 42:42Then the the Lund group
  • 42:43I told you about came
  • 42:44out with another project that
  • 42:46was very large and very
  • 42:47well done.
  • 42:49It showed the opposite. They
  • 42:50said that the basal group
  • 42:52was resistant to neoadjuvant chemotherapy
  • 42:54and their genomically unstable group
  • 42:56was more sensitive.
  • 42:58And so then there's another,
  • 43:00then someone's like, what is
  • 43:01going on here? So,
  • 43:03forget what the what group
  • 43:04it was, but they basically,
  • 43:05they took some cancers and
  • 43:06they sent them out for
  • 43:07decipher and got them profiled.
  • 43:09Then they did the lung
  • 43:10classification,
  • 43:11and they were all over
  • 43:12the place. So there was
  • 43:13there was an overlap.
  • 43:15The basils from one didn't
  • 43:16overlap with the the basils
  • 43:17from the other.
  • 43:19And so the I think
  • 43:21that goes to the tell
  • 43:22the story, like, whenever we
  • 43:23say basilar, we say luminal,
  • 43:24we're saying something that's somewhat
  • 43:26arbitrary.
  • 43:27Who's basal? Who's luminal?
  • 43:29There's there's
  • 43:31there really, I think that
  • 43:32the way to do this
  • 43:32isn't to say this is
  • 43:33a luminal cancer or basal
  • 43:34cancer, but rather, what are
  • 43:36the processes?
  • 43:37What are the signatures that
  • 43:38are active and how can
  • 43:39we use those to inform
  • 43:41therapy?
  • 43:42So at this point, I'm
  • 43:43I really am not an
  • 43:44advocate at all of the
  • 43:45descending molecular subtypes,
  • 43:47in the clinical setting. I
  • 43:47think there's no we don't
  • 43:49know how to do it,
  • 43:50basically, and we don't know
  • 43:51what to do with the
  • 43:51information once we get it.
  • 44:04Yeah.
  • 44:06So with those
  • 44:08with the base of our
  • 44:23Yeah.
  • 44:31So I don't know if
  • 44:32anyone who's looked at the
  • 44:33basal phenotype of noninvasive papillary
  • 44:35cancers. I would assume they're
  • 44:36high grade, but I I
  • 44:37don't know that.
  • 44:38But people have looked at
  • 44:40the subtype of these, the
  • 44:41flat carcinoma in situ, and
  • 44:42there is a subset of
  • 44:43those. There's a small subset
  • 44:44of flat carcinoma in situ
  • 44:45that has a basal phenotype,
  • 44:47and that's more aggressive. That's
  • 44:48associated with higher risk of
  • 44:49progression to muscle invasion, etcetera.
  • 44:51So, so it's not completely
  • 44:53false that there's like this
  • 44:54subset that start off basal.
  • 44:55I just think it's a
  • 44:56minority of them that do.
  • 45:00Anyone else?
  • 45:01Oh, yes. So the, a
  • 45:03lot of us working on,
  • 45:05cell lines. Yes. And and
  • 45:06the,
  • 45:07the prototypical aluminum cell lines
  • 45:10and for physical
  • 45:12cell lines,
  • 45:22Yeah. They do. It it's
  • 45:24kind of amazing, actually. Oh,
  • 45:25did you have more? Go
  • 45:26ahead. Go ahead. I can
  • 45:27explain.
  • 45:39So we haven't done the
  • 45:40latter yet, but but the
  • 45:42the former question, yes. So
  • 45:43some of these
  • 45:44do have similar histologies.
  • 45:47It's it's difficult to to
  • 45:48really compare them. And the
  • 45:50way that we've done it
  • 45:51historically is is with xenograft.
  • 45:53So if you grow, like,
  • 45:54the the cell in r
  • 45:54t four, for example, which
  • 45:55is a liminal cell line
  • 45:57in a subcapsular,
  • 45:59you know, kidney xenograft
  • 46:01in skin mice. It looks
  • 46:02like a papillary carcinoma, classic,
  • 46:04you know, papillary or theeloid
  • 46:06carcinoma. You grow a SCABER
  • 46:07cell line. It's a basal
  • 46:08one in the same model.
  • 46:09Even a subcutaneous xenograft, it's
  • 46:11keratinizing squamous cell cancer. So
  • 46:12the the histology does mirror
  • 46:14the molecular subtype very well.
  • 46:17But they're they're hard to
  • 46:18grow. Like, not every all
  • 46:19all these cell lines grow
  • 46:20easily in xenograft, some just
  • 46:22don't.
  • 46:23And so we've we've not
  • 46:24done that experiment, but that's
  • 46:25it's a
  • 46:27yeah, that's it's something I
  • 46:28thought about, but I've not
  • 46:29done it. They don't have
  • 46:30the state. It it's not
  • 46:32that impressive. So in culture,
  • 46:33yeah, like, the the r
  • 46:34t fours are kinda like
  • 46:35little little dots. They're little
  • 46:36papillary looking things, but nothing
  • 46:38is impressive as the xenografts.
  • 46:39But it really doesn't change
  • 46:41the just, like, the
  • 46:42the, you know,
  • 46:44the look of the cell
  • 46:45lines. So it suggests that
  • 46:46maybe some
  • 46:47of
  • 46:48the morphologic,
  • 46:49histologic
  • 46:50Mhmm. Is
  • 46:51derived from interactions from the
  • 46:53others. Yeah.
  • 46:55Yes. Yeah.
  • 46:56For sure.
  • 46:59Yeah. Go ahead.
  • 47:16Yes. So,
  • 47:17we
  • 47:18actually, I've I Andrew, I
  • 47:19just analyzed your data he
  • 47:20gave me, and so we
  • 47:21actually have some of this
  • 47:22we're looking at right now.
  • 47:24They're they appear to be
  • 47:25more basal in our hands
  • 47:26at least.
  • 47:27But in the hands of
  • 47:28others who have published on
  • 47:29this,
  • 47:30it it's it's
  • 47:32inconsistent. And it's it's a
  • 47:33similar kind of story that
  • 47:34if you look at spatially
  • 47:35distinct parts of a tumor,
  • 47:36you get different subtypes. If
  • 47:38you also look at the
  • 47:38lymph node metastasis or distant
  • 47:40metastasis, it it can differ,
  • 47:42from the primary as well.
  • 47:43So it really it's what
  • 47:44part of the main tumor,
  • 47:45you know, gave rise to
  • 47:46the MET.
  • 47:52Alright. No one else?
  • 47:54Oh oh, yeah. Go ahead.
  • 47:56Just in general, you found
  • 47:58lung classification that was reproducible.
  • 48:01I I don't think any
  • 48:02of them are that reproducible.
  • 48:03I think that it just
  • 48:04I mean, they're reproducible on
  • 48:06their own.
  • 48:07In the lung classification is
  • 48:08nice because they have got
  • 48:09some some biological,
  • 48:11you know
  • 48:13you know, consistency to it.
  • 48:14So, you know, like, their
  • 48:15lumenal types, there's two of
  • 48:16them and they're they classify
  • 48:17them based on the cell
  • 48:18cycle gene that's been knocked
  • 48:19out.
  • 48:21But I don't I don't
  • 48:22wanna use the word consistent.
  • 48:23I think they're all consistent
  • 48:23with themselves, but they're just
  • 48:24not consistent with each other
  • 48:25because it depends on the
  • 48:26genes you pick to put
  • 48:28them in the different groups,
  • 48:29and they can be, a
  • 48:30little inconsistent based on that.
  • 48:35Alright. Well, thank you all.