Pathology Grand Rounds: October 12, 2023 - Boyi Gan, PhD

October 13, 2023

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Boyi Gan, PhD, of MD Anderson Cancer Center, presents on, "Ferroptosis and Disulfidptosis in Cancer."

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00:00OK. Good afternoon, everyone.
00:02It's almost 12:30, so we'll get started.
00:05It's my great honor to introduce
00:07my good friend, Doctor Bo Yi Gan
00:09from MD Anderson Cancer Center.
00:12Bo Yi currently is Ng and Hannon T
00:16Hawkins Distinguished professor of
00:19Cancer Research and also so as the
00:22director of radiation and cancer
00:24metabolism research program at
00:27the radiation oncology division.
00:29Actually I know boy since high
00:33school we we went to the same high
00:36school and then we we connected
00:37that when we were doing a post doc.
00:39I identify the Cancer Institute
00:41and where he did his post doc with
00:45Ron Dipino's lab and he studied his
00:48NAB laboratory in 2011 I I think
00:51and then rose through the ranks
00:54became full professor in 2021.
00:58He has done an auto
01:06very nice work on cancer metabolism
01:10and cell deaths specifically for
01:13pertosis and the new cell death
01:16mechanism called the disulfidipotosis.
01:18It's difficult to pronounce,
01:24has published you very well with
01:26many papers in Nature and Nature,
01:28Cell Biology and I I think he will
01:31tell you more about those findings
01:34today without further ado for you.
01:44So really want to thank you for the for
01:47the invitation and kind of introduction
01:50and it's really my great pleasure to
01:52visit Yale and have the opportunity
01:54to you know talk about our research
01:56at the pathology and grand rounds.
01:58So this so my presentation,
02:01so yeah, so this is my title and
02:03this is the disclosure slides.
02:06But just to give you a little
02:08bit introduction about our
02:09overview of our research program.
02:10So as changes to alluded that we are
02:13interested in studying cosmetabolism
02:15and the survival cell test and we're
02:18interested in the question basically
02:20how cells survive or die you know very,
02:23very fundamental question and
02:24particularly how cell die survival
02:26by on the metabolic stress condition
02:28and that we are also interested
02:30in targeting those metabolic
02:31vulnerability for kind of therapy.
02:33Now as Ching just mentioned that we are
02:36studying two types of cell deaths right now.
02:38The first is cell deaths called for
02:42pulses and the second form of cell
02:45deaths actually was discovered by
02:47us recently called disulfide tosis.
02:49So I think quite some people
02:52ask me how to pronounce it.
02:53So basically this the the D here is
02:56not pronounced so so yeah so you see
02:59the so this D is not pronounced so
03:01it's disulfide toss about you know in
03:03rich respect I I should make it the
03:05name a little bit easier for us to
03:07pronounce it but basically I refers to
03:10the disulfide stress induced cell deaths.
03:12So I'm going to also talk about
03:14this new form of cell death in the
03:16second part of my presentation.
03:18Now for the first part So
03:20what is perposes right.
03:21So you know think for the either the
03:24research fellow here or any clinician
03:25here you probably know apoptosis right.
03:27So this is the widening most widely
03:30studied form of cell death for process
03:33was discovered now I think 11 years ago by
03:37brand Stockwell at Columbia University.
03:39But basically refers to the the
03:42cellular states when the cells are
03:44overwhelmed with the lipid approximation.
03:47So this is 1 type of osteo damage
03:50on cellular membranes.
03:52Now you can think about this as
03:54basically in your cells those
03:55normal metabolic activities,
03:57they can generate all kinds of you know
03:59error on and also one type of fatty
04:02acids called polyunsaturated acids.
04:05And there are also enormous body
04:07activity from mitochondria.
04:09So all those normal metabolic activity
04:12they can generate leave the proxies okay.
04:14So this leave the proxy basically
04:16as a byproduct of normal metabolic
04:18activities in our cells.
04:20But then then we also have this
04:23antioxidant defence system which
04:25basically are designed to quench to
04:28counteract those LEAP deproxides, OK.
04:31So basically the ferposis reflects
04:33a similar state in which this the
04:36metabolic activity which drives LEAP,
04:39deprox,
04:39the park station far overwhelms those
04:42the the antioxidant defense systems.
04:45OK, now this occurs when for example,
04:48those antioxidant oxidant defense
04:50system is inactivity.
04:52So I'm going to mention a little
04:54bit about what
04:55are those our current understanding
04:57of this antioxidant defense systems
05:00involving for positive defense.
05:01So this part is the most important
05:04defense system in our cells.
05:05This involved this key enzyme called
05:08the glute cyan proxies 4 or GPX 4.
05:10So this is the enzyme which basically use
05:13glute cyan as its cofactor to directly
05:16you know quench those lipid peroxides.
05:19This also touch on another
05:21transport of protein called SRC 711.
05:23So this is a cystine transport.
05:25As you know we have many,
05:26you know our cells contain many
05:28amino acid transported can import all
05:30kinds of nutrients or amino acid.
05:31But this guy is specifically transport cyst.
05:35OK, cystine and cystine was important,
05:39the cells were reduced to cystine.
05:41So I will get get back to this part at
05:44the the second part of my presentation.
05:46But now just to know that the system
05:49provides the key precursor for glucing
05:52biosynthesis and therefore provide
05:54the key resource for the antioxidant
05:57defense system regulated by GPX 4.
05:59So this pathway is the most important one
06:01and if you inactivity this antioxidant
06:04defense system and then that can use
06:07to the overwhelming need to peroxation.
06:09So the quick and accumulating the cells,
06:11they eventually kill the
06:13cells through for process.
06:14So those compounds are some
06:16of them are summarized here.
06:18So they are basically those are the
06:20so-called for process inducers of fins.
06:23So they're actually the inhibitors of those
06:26proteins involving anti for process defense.
06:29So for example this you're asking why
06:31did they use in the research actually
06:34inhibits the system transport right And
06:36the RSS three are the GPS 4 inhibitors.
06:40So those are the compounds which are
06:41widely used in the field is for process,
06:44inducer to to study for process.
06:46Now on the flip side we also have for
06:49process inhibitor so Zynca block for
06:51process mainly act as the radical
06:53trapping and oxidant to broad for process.
06:56Now those compounds right yeah for
06:58process inducer for process inhibitors
07:00the not only provide important you
07:02know tools plus to study to understand
07:05the the mechanism of process but also
07:07really provide potential targets or
07:09the the approach or you know tools to
07:12to to as a for therapeutic attacking
07:15of for processing disease like we
07:17talk about for processing disease.
07:20So you know particularly for any
07:22clinician here there are two you know
07:24ways to target for process in disease.
07:28So on one side many disease have now
07:30have been shown to be associated
07:32with excessive for process.
07:33So you have too much for process
07:35that can cause disease.
07:36I think it's a relatively easy to
07:38understand this So if you have too
07:40much cell that's 'cause that's bad for
07:42you know for example for the the the,
07:45you know the high cost neuron degenerate
07:47disease can cause acute kidney injury
07:49and so on is similar profusion induced
07:51organ damage and so on so forth.
07:54So so that's you know certainly
07:56you know a pulses
07:57has been implicated in many of
07:59this disease and now there is the
08:02increase in appreciation for pulses.
08:04Excessive for pulses can
08:06also 'cause this diseases,
08:07So in those for those diseases
08:10has had there have been expensive
08:12preclinical models to support to use
08:14for process inhibitors to block for
08:17process and therefore can be used to
08:19potentially treat those diseases.
08:21Now I'm going to focus on is the
08:23other side is the cancer which has
08:25also been shown to be associated
08:28with impaired for sources.
08:29So that means the for process
08:31like apoptosis actually is a
08:33tumor suppression mechanism.
08:34It normally find you to as a
08:36tumor suppression as a barrier
08:37to for tumor development.
08:39So therefore if this for process
08:42mechanism is inactivity so that
08:44can leads to tumor formation and
08:47the consequently many studies
08:49including our study I've shown
08:51that you use for process inducers.
08:53So in this case is to induce
08:55vertosis for treating cancers.
08:56So that would be the focus
08:59of my presentation.
09:00Now.
09:00So first in order to target the ferposis
09:02in cancer we need to 1st understand the
09:04what's the rule of ferposis in cancer,
09:06right.
09:06So the way for process inactivation
09:09can use to tumor development
09:11progression with the sarsis is
09:13through different mechanism as I
09:15just alluded at beginning of my
09:17presentation in the ferposis kind of as.
09:19A it's an imbalance between the
09:21error metabolism that you know the
09:24metabolic activity just mentioned
09:26which drive the peroxation including
09:28error metabolism or the metabolism
09:30versus the other side you have this
09:32the anti for process defence systems.
09:35So think about this right.
09:36So if you have too much the activities
09:39which push the lipid peroxation that
09:42can promote for process so cancer,
09:44they find a way to inactivate
09:47those metabolic activity right,
09:48which normally pushed you to proxy.
09:51For example they can limit the
09:53profile for containing false belief
09:55synthesis or prostation or can
09:57restrict the bare arrival ability.
09:59So those kind serves to inactive the
10:02first process and therefore to a few
10:04tumor progression and that's classes.
10:07But perhaps the most important
10:09mechanism is the third part actually
10:11by up regulating the the antioxidant,
10:13the defence system against per process
10:16caust in stressing the antifeptosis
10:19mechanism so that can also inactivity
10:22pertosis and therefore to promote
10:24tumor growth and also metastasis.
10:26So the third part is I'm going to
10:29mention one example that's from our
10:31previous study that's actually how
10:32we get into this field is when we
10:35at a time we were studying a team of
10:37scarcity gene called called BOP 1.
10:39So,
10:39so actually BOP one is directly
10:42to involving IP genetics.
10:43So you said,
10:45but in this case is to regulate
10:48the ubiquitination on histone.
10:50As you know histone can be
10:51regulated through different post
10:52transmission modification, right,
10:54such as estimation.
10:56But histone ubiquitination can also
10:58play important role in genetic
11:00regulation of gene transcription.
11:02In this case the BOP one is to
11:05remove ubiquity on the
11:07on the keystone H2A and therefore
11:08to modulate the gene transcription.
11:10So in this case we we did the
11:12genetic the you know RSC,
11:14TC analysis and we identified this
11:17gene ICS 711 as I just alluded
11:19earlier as the system transporter.
11:21So this is a key targets of BOP 1.
11:24So basically BOP one for him to remove
11:27the ubiquity from H2A and therefore
11:29surprise the expression of this transporter.
11:31Now that is to the decrease
11:33the import of the system,
11:35decrease bio biosynthesis since sinuses
11:37of glucion and therefore the cells
11:40the can are more sensitive to for
11:43process when there is a wild type AP1.
11:46Now POP one is the tumes part of the gene,
11:48so it's lost in some of you know kidney
11:50cancer and other form of tumors.
11:52So in the tumors in those cancers
11:55the loss of the POP one.
11:56So as she mentioned other people
11:58I was assume that PBS three can
12:00also regulates this the expression
12:02of SSSC development.
12:04So loss of BAA point or PBS three
12:06that needs to the key repression
12:08of this SSC 711 transcription.
12:10So that in other in other word is
12:13that this expression is now up
12:15regulated So those tumor cell with
12:17deficiency of BAAA consequently are
12:19more resistant for ******* and the
12:21consequently is to tumor formation.
12:23So that basically is the the study
12:25we show that the PowerPoint division
12:27promoting the growth and it's the
12:29partners through up regulating this
12:31transport immediate for process defense.
12:33So as you mentioned this was
12:35previous work by a previous trainee
12:37by Ellie from our lab.
12:39So this and odd work are really established
12:42for process just like apoptosis as a
12:45as a key to suppression mechanism.
12:49So now I'm going to talk about the
12:51our current understanding how in terms
12:53of how we can target this type of
12:55cell that's in in kind of therapy.
12:57So one way you can do this is to
12:59basically some tumors we know they
13:01are resistant to to for process.
13:03So therefore you can design strategy to
13:07resize those resistant tumors to process.
13:09So I just use one slide one key data
13:14to to to to illustrate this point.
13:16So again this was done by Eli.
13:18So in this study we showed that
13:20M2 or plus we actually can also
13:22regulate the for process.
13:24So basically the M2 hyperactivation makes
13:26them more resistant to for process.
13:28So I don't have time to to get into
13:31the detail that in terms of mechanism
13:33but this has suggest a way to use
13:36combine M2 inhibitor with with for
13:38process inducers as a combination
13:40therapy to recently ties some of those
13:43tumors to for process as a therapeutic
13:45strategy what kind of treatment.
13:47So one example is shown here when we
13:49combine this drug called Ike which is
13:52a proposes inducer which can block
13:54the system and transport activity.
13:56When we combine Ike with ample inhibitor,
13:58I will see a more you know the
14:01combination therapy effects in
14:02this PDX models to
14:04surprise tumor growth.
14:05Now the second point,
14:08second strategy is to basically
14:10combine those for process inducer
14:13with some of the conventional kind
14:15of therapy including radiotherapy,
14:17chemotherapy and immunotherapy.
14:18We now appreciate that those therapies
14:21they can also induce for process right.
14:24So therefore make sense to combine for
14:26process inducers with those therapeutic
14:28strategy therefore to further boost the
14:31induction for process as a therapeutic
14:33strategy in kind of treatment.
14:34So again I'm going to use one
14:36example from our research.
14:38So this was done by Guan
14:40a student in the lab.
14:41So he discovered that the the airlines
14:44radiation right which is used the
14:46commonly used to treat cancers as a
14:48part of the radiotherapy can induce.
14:50So I'm going to use this cartoon
14:52to summarize his finding.
14:54So he found the airlines radiation
14:56can use lipid prox station and this
14:58can kill cells through for process.
15:00But more importantly is we know that many
15:03tumors are resistant to radiotherapy right?
15:06So they have radio resistance and the
15:08part of the reason why some tumors are
15:10resistant to radiotherapy is because
15:12they have certain mutations because
15:14those tumors are more intrinsically
15:16resistant to radiation such as when the,
15:18you know in some of the lung cancers
15:20they have key point mutation and they
15:22will get to this why those tumors
15:24will be resistant to for a process.
15:26But when the key point is mutated,
15:29the lung cancer cells are generally more
15:31resistant to to for a process because
15:34they have up regulation of some of the
15:36genes involving for a process defense,
15:38right.
15:39This including GPS 4 and SLC 711.
15:42So we found that reason why those tumor
15:45cells are radio resistant is because
15:48they actually are resistant to airline
15:50radiation induced the the lipid peroxation.
15:53So as showing this cartoon kind of
15:55like those soldiers you can see
15:56they have the shells there too.
15:58So therefore they can defend against
16:00this lipid peroxation batch.
16:03Now therefore based on this finding
16:06we propose to use those for process
16:08inducers as a way to basically
16:11re sanitize those radio resistant
16:12tumors to radiation.
16:14So if the effect of those radios,
16:16the ferptosis user here it's kind
16:18of like you basically disrupted the
16:19shells here right used by the soldiers.
16:22So then those soldiers now will be
16:24directly exposed to the lipid peroxides
16:27triggered by the allies radiation.
16:29So they're killed by those lipid peroxides.
16:33So the so the approach here is
16:34basically again is to use proposed
16:36inducer as a radio synthetizer.
16:38And as one example again we use the
16:41keypoint mutants noncat PDX model and
16:43here we use a different for process
16:45inducer called the sulfasalazine.
16:48This is FDA approved the drug and again
16:50is the first process inducer which
16:52have been shown to block SLS system
16:5411 induced immediate the system transport.
16:57So as as you can see the subzalasine
17:00treatment allow doesn't have much effect
17:02but we can dramatic can significantly
17:04synthetize the tumors to radiation.
17:06So therefore we combine it has more
17:09dramatic effect to suppress tumor growth.
17:12So this and other studies oh I just want
17:15to mention that I want to talk a little bit
17:17more about this keep one mechanism here.
17:20So key point is some of you might
17:22know it's basically is a part of
17:23the you looking like it's complex.
17:25It's normal function is to degrade a
17:27transcription factor called nerve two.
17:29OK now nerve two is a master transcription
17:32factor involved in antioxidant defense
17:34can regulate many chains involved in
17:36defending against the antioxidant
17:38stress including for a pulses.
17:40So for example this assistant transport
17:42s s 711 is the one of the transcription
17:44target of nerve 2 and involve also
17:47other genes involving glute sign of
17:49biosynthesis also regulated by nerve two.
17:51Now when keep Y is mutated in non
17:55casters so that means to the nerve 2
17:58stabilization so the upper regulation
18:00of SSS 11 and other genes so that
18:03kind of promotes the GPS 4 pathway
18:06right in for process defense.
18:08So that explains why the keep mutant
18:10cancers are resistant to for process.
18:13Now we further show that this analysis
18:16gene involving for process defense.
18:20So this was discovered by others,
18:22just to put a little bit of context here,
18:24initially people believe the GPS 4,
18:27you know, a few years ago.
18:28Yeah.
18:29So the field at the time people
18:31believe the GPS four is the only
18:33protein or this is the only pass
18:35we will be for process defense.
18:37But we now know that there are additional
18:40so-called process independent mechanism
18:42involving for process defense and
18:45this FSP one its full name is for
18:47process surprise of protein one is
18:50one of the major mechanism which is
18:52operate independent of GPS pathway
18:54to defend against per process.
18:57Now mechanistically this is the
18:59OXY reductase which acts to reduce
19:02this metabolite called COOQ.
19:04So another name of COOQ is Ubiquinol.
19:07OK.
19:08And two is reduced form called
19:10ubiquinol or Coq H2.
19:12Now I will get back to this nature
19:14and this probably is commonly known
19:16involving the electron transport chain,
19:18right.
19:18So if you are you know the read the
19:21back hamstring textbook you would know this.
19:23But the Coq H2 actually has another role.
19:26It actually can also act as a
19:29radical trapping antioxidant.
19:30It's kind of similar to some of the
19:32first process in use of inhibitors
19:34I mentioned earlier.
19:35So you can directly and also can
19:38inhibit to those can block those if the
19:41peroxides and thereby surprise for a process.
19:43So this would now appreciate.
19:44This protein is also important
19:46in for pulses suppression.
19:48So we found that we also discovered
19:51this FSP one is also another
19:54transmission target of nerve two and
19:56therefore not only under directly
19:58to this branch to to in for process
20:01defense but also operate the FSP 1.
20:03So there are two branches major
20:05branches in for process defense
20:06are regulated by nerve two.
20:08So one of the key data here I just show
20:10one data here. So if you with no call
20:12keep one in non kind of cell lines
20:14and you can see the stabilization
20:16of nerve two and this also needs
20:17to the upper regulation of FSP
20:19one in those non kind of cells.
20:23So we're further sure that we
20:24can also targeted this pathway
20:26for for for radiation therapy.
20:29Now so this was done by prime of a student,
20:32previous students with one together.
20:34So we can use either FSP 1 inhibitors.
20:37So as I mentioned,
20:38this is the Ox to Ox to reductase.
20:41So it's a enzyme,
20:43so there's a inhibitor available or we can
20:46target off stream the Coq biosynthesis.
20:48So example can use 4 CBA to block
20:52the Coq biosynthesis and when we
20:54either use the FSP inhibitor of four
20:56CBA and then we can resynthesize.
20:58So here as you can see the green
21:00line here you we lock out TP1
21:02makes them more radio resistant
21:04and that we can resynthetize those
21:06radio resistant the cell lines by
21:08treating those cells with with
21:11either FSPN inhibitor or four CBA.
21:15In wave world we can also combine
21:16force EA with radiation and we can
21:18see a very dramatic suppression
21:19of the tumor growth in this keep
21:22one mutants non cancer PDX models.
21:26So this data really suggests that
21:28you know again different approaches
21:30we can target a user SSS 711 or
21:33targeted different you know components
21:35such as FS21 pathway to to to
21:39synthesize tumors to radiation.
21:41Now this data and others allow us to
21:44proposed the strategy you know to
21:46form this so-called a crowd resistant
21:48to therapy and the error center or
21:51articenter you know institution and
21:53fortunately this was supported by
21:56alternate UV 4 centigrade from ACI.
21:59The overarching theme of our center
22:02is to basically identify the strategy
22:04to induce process as a therapeutic
22:07strategy to to overcome a crowd
22:09radio resistance as well as other
22:11therapy resistance.
22:12So,
22:13so we're really work on this theme
22:16and together with with either other
22:19groups in the Indiana and also other
22:22PIS from the alternate network to
22:25tackle this important question.
22:28So OK,
22:29so now I'll get back to to the
22:30original slides, right.
22:32I'm going to you know I was talking
22:34about the different strategies to
22:36to target it for processing kind
22:38of therapy and I just mentioned
22:39to combine for process inducer
22:41with radiotherapy.
22:42I'm not going to talk
22:43about the immunotherapy.
22:44I think this is again very,
22:46very interesting topic.
22:47But this was also have been demonstrated
22:50by other researchers in the field
22:52but they are the third strategy is
22:55to really exploit the for process
22:58as a vulnerability in cancer.
23:01So what I mean here is that it turns
23:02out that even though for a process
23:04is a tumor suppression mechanism.
23:05So therefore many tumors the
23:07for example keep the keep mutant
23:09cancer or BOP Y mutant cancer,
23:11they are more resistant to for process.
23:14But in some other cases those
23:16tumors actually are vulnerable.
23:18They actually are more sensitive to for
23:20process inducers compared with these other
23:23kind of cell lines or or normal cells.
23:25And there are different reasons why some
23:27tumors are vulnerable to for process.
23:29So for example some tumors because
23:32of the metabolic reprogramming the
23:34for example they have a high levels
23:36of profile polyunsaturated acids,
23:38so therefore they are more resistant
23:40to fur pulses.
23:41They may also have increased in
23:43the bare iron levels and you know
23:44in those tumors therefore they are
23:46also more vulnerable to fur pulses.
23:48Another strategy is the some of the
23:50mutations such as the mutation in the
23:52HIPAA pathway so they can regulate a
23:55certain genes involving Fertausis.
23:56So when the when those two in the
23:59HIPAA pathway was mutated that
24:01needs to also the high increase
24:04the sensitivity to for a process.
24:08But the third strategy here is the
24:10imbalances in Fertausis defence.
24:12So you can think about the Fera
24:14process defense as the the basically
24:16there are two arms, right?
24:18So Y is GPS 4,
24:20so GPS four is the most important guy, right?
24:22Infer process defense.
24:23Then there are also other backup systems,
24:26right? Those are collectively called GPS 4.
24:29Independence mechanisms to
24:30to defend against purposes.
24:33I just mentioned FSP one is
24:35one such proteins.
24:36Then there are others I'm
24:37going to mention later Now.
24:39So you have two arms here
24:41to defend against purposes.
24:43So if one arm is defective then the
24:45cells have to be more dependent on
24:47the other arm for fratosis defense and
24:49therefore that make those tumor cells
24:52are more sensitive to the fratosis
24:54inducers which targeted the other arm,
24:57right.
24:57So one way to help you understand
24:59this is you know as many of you
25:01know to use the POP inhibitor,
25:03the treated BRC one division cancer.
25:05The rationale here is that that
25:07there are different ways to repel it.
25:09In A1 require you know PRC one,
25:11the other require top.
25:12So then in the PRC one mutant kind
25:15of cells they have to be more
25:17dependent on POP foot in repair,
25:18so therefore more sensitive to POP inhibitor.
25:21So this is kind of similar concept here.
25:24So to one one example to illustrate
25:27this strategy is from our recent study
25:30in which we discovered this protein
25:33called THUDHE MOB inferosis defense.
25:36So THUDH is an enzyme involved
25:38in in pure medium biosynthesis.
25:40OK,
25:41but it's interesting in that because
25:43this is the protein localized
25:44on like chondra in the membrane,
25:46so you converse this option
25:49metabolite called THO to OA.
25:51So both are involved in pyramid
25:53biosynthesis but this is reduction,
25:55this is the oxidation reaction right
25:57from conversion from the THO to OA
26:00and this needs to be coupled with a
26:02reduction reaction and which is a
26:04conversion from Co Q to Co QH two.
26:06As I alluded earlier,
26:07Co QH two is involving in this case
26:09is involved in the electron transport chain.
26:12So the Co QH two then you try
26:14to convert
26:14it will be be delivered to complex
26:163 or the electron transport.
26:18But as I've just mentioned the
26:20quick H2 extra has another rule.
26:21You can also act as radical tracking and
26:25and oxidant to detoxify lipid peroxides.
26:29So we show that the GOGHD besides
26:32its canonical rule involved in
26:34the the pure medium biosenses,
26:36it can also can actually also
26:39suppress for process in mitochondria
26:41by generating Co QH two.
26:44So now I just mentioned as
26:46a protein right as FSP one,
26:48it has a somewhat similar function
26:50right because biochemical it
26:52also generate the Cocker H2.
26:53But the difference difference between
26:56this protein is their localization.
26:58So DHUDH localize in mitochondria in
27:01the membrane versus FSPN plasm membrane
27:04and other non mitochondria compartment.
27:06So these two proteins they can
27:09also depend against for process
27:11at different localizations.
27:13And also interestingly this other
27:14protein called the GPS four as I
27:16mentioned is the most important
27:18protein involving for process defense.
27:20You have different ice forms,
27:22so one neuchalizing cytosol,
27:23the other neuchalizing mitochondria
27:25together you can think about a picture
27:27here is the different proteins,
27:28the neuchalizing different compartment
27:30to defend against the for process.
27:33OK. So that's the bottom line here,
27:35but utilize this finding we think
27:38about OK maybe in the cells with
27:40if you have this GPS four,
27:42let me use this next slide,
27:45I'll ask you this point.
27:46So in this tumors with if you
27:50have low or high GPS 4,
27:51if you have low GPS four,
27:53then those tumor cells they have
27:55to be more dependent on other
27:57GPS for independent mechanism to
27:58depend against for process, right.
28:00So have to be more dependent on
28:02for example THUTH and therefore
28:04those tumors now becomes more
28:06sensitive to DHUDH inhibitors.
28:07So we've done a number of experiment,
28:09one experiment is used the
28:11the preclinograph model.
28:12You can see in this in this
28:15particular Xenophra model the GPS
28:174 expression is low and therefore
28:20when we treat the tumors with the
28:22PQR which is DHUDH inhibitors,
28:24you can see a more obvious
28:27suppression effect on tumor growth.
28:29They suppress the tumor growth can
28:31be restored by lead prostate as you
28:34mentioned this is for a process inhibitor.
28:36So we should use this to show that the
28:38suppression of the tumor growth was
28:40really caused by the induction of process.
28:44So the bottom line is if you
28:46tumor have low expression GPS 4,
28:48the DHUDH works better than in
28:50the tumors with high GPS for the
28:52reason is because in the GPS high
28:54tumors we just inactivity DHUDH.
28:56The GPS four is there to continue
28:58to defend against process.
29:00So that explains why the DHU,
29:04the PQR,
29:05the DHUDH inhibitor fails to have much
29:08obvious effect to surprise tumor growth.
29:12So the bottom line is we propose to
29:13use DHUDH inhibitor to specifically
29:16induce for process for therapy
29:18in GPS for low tumors.
29:20So here Oh yeah,
29:21here I just want to mention
29:23another point of this
29:24this finding is that DHUDH as just
29:26mentioned is the protein localized the in
29:29the mitochondrial in the membrane, right.
29:31But there is an issue with this pathway.
29:34So this pathway is pyramid biosynthesis
29:37involves 3 lines called CAD,
29:40DHUDH and the umps.
29:42Now the CAD and umps nucleus in cytosol
29:47versus DHUDH leuclide in mitochondria,
29:49mitochondria in the membrane.
29:51So they're separated by this
29:53mitochondrial auto membrane.
29:54Now as you might know that
29:57many enzymes involved in the
29:58meta in the metabolic pathway,
30:00they actually formed this
30:02metabolic market enzyme complexes.
30:04So they can form complexes so-called,
30:07so, so therefore the metabolite can
30:09directly channel the from the upstream
30:12enzyme to the next one, right.
30:13So that kind of facilitates
30:15so-called the substrate channeling.
30:17So that's very common for example
30:19in the electron transport chain all
30:21those complex that form a so-called
30:22super complex to really promote the
30:25efficiency of the electron transport.
30:27But in this case this all all these
30:29airlines look as a different compartment
30:31which is kind of puzzling wide the cells
30:33were designed like this way right.
30:35So you really doesn't make sense
30:37in terms of the increase the
30:39maintain the efficiency of the the,
30:41the subject channeling.
30:42But so I just want to mention this
30:44is not this study was not from our
30:46lab but this figure the cartoon was
30:48John from a commentary I mentioned
30:51I discovered I introduced this
30:53study this publication.
30:54But what they discovered is actually
30:56these three enzymes they can form also
30:58form a complex but in this case even
30:59though they leukalize in different
31:01compartments as they can use this
31:03transmembrane protein leukalize on
31:05the mitochondria auto membrane called
31:07VDS 3 to collect all them together
31:10as they're able to facilitate the the
31:12the the substance challenging between
31:14this this enzymes and therefore
31:16to not only promote peer meeting
31:19biosynthesis but also to increase the
31:21efficiency in for process defence.
31:23So they call this complex as peer
31:26peer meeting or some with basically
31:29used to the proposed this complex
31:32can promote the for process defence.
31:35OK.
31:35So I want to give a brief summary for
31:37the first part of my presentation.
31:39So I introduced the concept of process.
31:41I mentioned the different ways to
31:44target this cell that's in treating
31:46different diseases right and also
31:48mentioned the in cancer in in
31:51in tumor development for pulses.
31:52In power for pulses can drive
31:54tumor development progression and
31:56metastasis with different mechanisms.
31:58I mentioned the briefly mentioned
31:59that you know by Mimi team profile
32:02synthesis or restricting liberal
32:04availability but also more important
32:06than perhaps is to up regulate the
32:09cellular defence system against for pulses.
32:11One example is in the case
32:13of PowerPoint mutant cancer,
32:14the upper regulation of AT s s 711.
32:17Well,
32:17I then talk about how to target
32:19for processing cancer right.
32:21I talk about different strategies.
32:23The 1st is to reason the highest
32:24resistant tumor to for process such as
32:27by combining and to inhibit through
32:28is for process inducer.
32:30The 2nd is combined for process
32:32inducer with others conventional
32:34therapies such as radiotherapy.
32:36And the third is to explore for
32:38process vulnerability in cancer.
32:40And I also mentioned different mechanisms.
32:42One is to use the imbalances in
32:46feroptosis defense such as targeting
32:49DHUDH in GPS for low tumors.
32:51OK. So now I want to switch the
32:53gear a little bit here to the
32:56second part of my presentation.
32:58Now actually the the bisulfi pulses
33:00I'm going to just to to to to talk
33:04about actually relates to feroptosis.
33:06It's actually how we get into this
33:08new formal cell that just to kind
33:11of mentioned a little more here is
33:13this for a process that mentioned
33:16the can be defended by the GPS 4
33:18pathway which use uses Glusayan right.
33:21But glusayan as you know is
33:23a trip peptide right.
33:24It derives from glycine,
33:25cysteine and the glutamate among which
33:28the cysteine is the written limiting
33:31precursor for Glusayan biosynthesis.
33:33So basically cell needs
33:35cysteine to build up glusayan.
33:37Now the cysteine is like many
33:39other amino acid or nutrients,
33:41the cell have the transporter to import
33:44the system from extracellular space.
33:47But they have a problem here and the
33:49reason is because this is released
33:52to the different redox environments
33:54between the outside versus inside cells.
33:58Outside cells, the actual cellular space,
34:01they have oxidizing environment
34:03versus inside cell.
34:04In the cytosol we have the
34:07reducing micro environment.
34:08So in the in the extracellular space
34:11because of the oxidizing environment,
34:14the cysteine is very unstable, right.
34:17So it rapidly oxidized it to a system.
34:21So as the structure in shown here,
34:22basically the system is the is the
34:25oxidized by America form of cysteine
34:28linked by a by sulfide bar is shown here.
34:31So in the actual center space if
34:33you just add for example in medium,
34:35if you add the system in the system
34:37were quickly oxidized to system.
34:39So consequently the system concentration
34:41is much higher than system.
34:43OK,
34:43but even though CR needs system
34:46for growth biosynthesis,
34:47but what they can get most from from
34:49the outside of the cells is the system.
34:51So therefore the cells actually
34:54use this transport.
34:55I just mentioned the earlier,
34:57it's called SRC 711.
34:59The other name is XCT to import system.
35:02OK, but then the system within cells,
35:05the system is then it's reduced
35:07to system and system is then
35:09used to synthesize gluosam.
35:11So this is some of the
35:12background knowledge here.
35:13But this system,
35:15commercial system is a reduction reaction
35:17across the reducing power called in ADPH.
35:20OK,
35:20so it turns out that this reduction
35:23reaction actually has a very
35:25important role in maintaining
35:27redox chromostasis particularly
35:28in those kind of cells with high
35:30expression of this transport.
35:31I just I should mention that this
35:33transport is highly expressed
35:35in your number of cancers.
35:36You know for example Q1 mutant non
35:39cancer or pop one mutant cancers.
35:41So so but it turns out this has a
35:44very interesting consequence.
35:46This is because it turns out the
35:48system is one of the is very insoluble.
35:50OK, so one of the needs to soluble
35:54amino acids, this also is here.
35:56Yeah, the solability is very low,
35:58yeah, it's actually the.
35:59So then because of the instability,
36:02the system, the high accumulation
36:03of system in cells is toxic.
36:06OK. The cells cannot tolerate
36:08to have a high levels of system
36:10inside inside the inside cells.
36:12So therefore they have to the system
36:14has to be quickly reduced to cystine
36:16and the cystine as you can see it is.
36:19So ability can be improved
36:21by more than 1000 fold.
36:22Now this as I just mentioned,
36:25this reduction reaction reports
36:26NDPH and we know that NDPH is mainly
36:29supplied from glucose through the
36:31pentons of phosphate possible.
36:33OK. So then based on this,
36:35it turns out this the tumor cells with
36:38high expression of this transporter,
36:39they need to import a lot of
36:41system in the cells.
36:42Therefore,
36:43they also need a lot of NDPH to
36:45support this conversion from system
36:47to system and consequently that
36:50make those cells more dependent on
36:52glucose to support this conversion.
36:56On the normal condition this is fine
36:57because for your cultural cells for example,
36:59you know those cells are culturally
37:01in the medium with plenty of glucose
37:03or even in the MAVO condition the
37:05glucose we have you know a high level,
37:07relatively high level of glucose.
37:09So normally this is fine.
37:10Even the tumor cells they have
37:11high experience is transported
37:12don't have any issue because there
37:14is sufficient supply of glucose.
37:16However if this glucose supply is
37:19limited somehow then those this
37:21cells now run into trouble and
37:23this is because the so because
37:25this glucose is limited so there
37:27is NADPH supply is limited and this
37:30conversion they don't have any pH to
37:33you know to mediate this conversion
37:35from cistine to cystine.
37:36So that means to the high accumulation
37:39of cistine in the cells with high
37:41expression of this transporter.
37:42And I can use a couple of data
37:44to illustrate to this model.
37:45So you can see in the tumor cell
37:47with over expression of this
37:49transporter and when we measure the
37:51system concentration inside cells
37:52and you don't see much difference
37:54between you know the control servers
37:56is over expression right again
37:58this transport import system.
38:00But if you measure system you don't see
38:02much difference and this because the
38:04system quickly is converted to system.
38:06So if we measure system,
38:07I don't show the data here you will
38:09see a huge increase in the sales with
38:11over expression of this transport.
38:13However if you cut your cells in
38:15the glucose free media and always
38:16see a massive increase of system
38:18concentration in the cells with
38:20over experience this transporter,
38:21this is complicated with dramatic
38:23depletion of NDPH.
38:25So shown here is the NDP plus to NDPH ratio.
38:28So you see it reverse the ways
38:30as a dramatic increase.
38:31So by this reflects A dramatic reduction
38:34of the NDPH reserves in the cells and
38:37then the cells now wrapped in your eyes.
38:40You can see there's massive cell
38:42deaths in the s s 711 over expression
38:44cells on the glucose starvation.
38:46Like she mentioned that this is the
38:49first observation actually were made
38:50actually this was initially made
38:52by a student in the lab primarily.
38:54So when she they actually she
38:57accidentally captured these cells
38:59on the glucose free medium.
39:01So she showed me the data and
39:02initially I didn't believe her,
39:04right, because if you think about it,
39:05it doesn't make sense right?
39:07Because it is very established that
39:10this transporter actually have a
39:12very established the the antioxidant
39:14role right pro survival rule.
39:16So you can protect it from protect
39:19cell from for process protect cell
39:21from other optic stress or genotoxic
39:23stress because it promotes are the
39:26synthesis of glue scion right.
39:27So I saw initially this doesn't
39:29make sense so she did a number of
39:31experiments to convince me so and
39:33other people repeat it so this is very
39:35very dramatic phenotype and turns out
39:37that and we didn't figure out the
39:39reason together with Xiaobo in the lab.
39:41So we now know this is because the
39:43increase the bisulfide molecules
39:45including system molecules in
39:46these conditions that chaos cells.
39:49So the way to improve prove this is
39:51to I'm going to I'm going to show the
39:53data later you can Add all kinds of
39:55compounds which as a reducing reagent
39:57and you can convert this system back
40:00to cysteine and that can rescue
40:02fully rescue this type of cell death.
40:05But here the question is right we
40:07need to sort OK we see this cell
40:09that's induced by bisulfite molecules
40:11but really what is the mechanistic
40:13basis right of this specified stress
40:15induced this cell deaths.
40:16So we first want to see, OK,
40:18this does this cell death belongs to
40:19any known cell death mechanism, right?
40:22A pulses or pulses?
40:24Like you know necroposis so on and so forth.
40:26So we can do this very easily in the lab.
40:29You can add just you can use those
40:31cell death inhibitor to see whether
40:32they can rescue.
40:33You can also know how the genes
40:35such as you know backspack,
40:37you can see whether that was
40:38also rescue the cell deaths.
40:39But as far we can,
40:40as we can tell none of those cell
40:43death inhibitor or you know compounds
40:45or genetic approach can rescue
40:47this cell death so soon.
40:49Here is a few examples.
40:51You can see the the the cell desk
40:53can be rescued by NAC but cannot be
40:55rescued by any of those inhibitors
40:58we have tested and furthermore it
41:00doesn't issue cleave the CASP 3
41:02or any other cell desk hallmarks
41:04now as a port positive control.
41:07Here I show you a few bisulf by
41:10reducing agents such as DTT by me so
41:12those can fully rescue this cell desk.
41:15So based on this finding and the other data,
41:17we then propose this as we call
41:21the term disulfide process to
41:23describe this type of cell death.
41:25But then the question is right,
41:27what what what's the what
41:28is the mechanism right?
41:30Is any different components involving
41:32the cell diets or different
41:34biology biochemical pathways.
41:35So we took two approaches,
41:37one is the proteomic approach.
41:39So we're basically want to look at whether
41:42this disulfide accumulation needs to
41:44that disulfide bounding the anti proteins.
41:46We did a proteinomic analysis to a surprise.
41:49The major proteins which undergo
41:51disulfide bounding under the
41:53conditions during the TYSOP courses.
41:56Actually those cytoskeleton
41:57acting cytoskeleton proteins.
41:59So this is surprising to us.
42:01And here I want to mention a
42:03few proteins with many dated.
42:04So for example phenomi,
42:06myosin,
42:07painting and even acting self.
42:08The way we do this is we can run the
42:10chair on the non reducing condition.
42:12So for any of the training here must
42:14have done western blot right and you
42:16know you have to add a better ME or
42:18TTT right in the in the in the buffer.
42:20So you run it,
42:22you're on the reducing condition.
42:23So when you do the western blot,
42:25you always run the western blot
42:27on the reducing conditions.
42:28But if we do this experiment now
42:31on the non reducing condition,
42:32you're going to see all this span
42:34shift and this is because they form
42:36this specify bounding and therefore
42:37show the migration retardations right.
42:40So this is not because post relation
42:41or any other post transmission
42:42modification because we have
42:44control here we have the reducing
42:46gel here on the reducing condition
42:48and you can see those Spanish shift
42:51now is totally is gone.
42:53Now this span ships there's
42:55you know those reduce the the,
42:57the protein,
42:58the disulfide bounding those proteins,
43:01it can be fully rescued by the
43:04XCT or SS711 knockout right.
43:06So again showing here this is really
43:08caused by this assistant uptake in the cells.
43:11So you can not call this key transporter.
43:13You can fully abolish this that by
43:16sweat bonding those proteins and this
43:18also can be shown and other ways to
43:20do the cytoskeleton staining, acting,
43:22cytoskeleton staining staining.
43:23You can see the normally the cell
43:26show this very nice stress fiber
43:28and also the the acting standing
43:30under this similar cortex but then
43:33the structure is very much disrupted
43:35in this glucose star glucose
43:37starvation conditions and again if
43:40we knock out this transporter that
43:42we can totally rescue this this
43:45cytoskeleton disruption phenotype.
43:48So OK so this shows the somehow
43:50this cell does have something to
43:52do with cytoskeleton but you know
43:54I mean you know pathways right.
43:56So we did another approach we did is
43:59to use the CRISPR screening, right.
44:01So you can easily do the CRISPR
44:03screening to identify the proteins
44:05or genes somehow differentially
44:07accumulated it on the two conditions
44:09that glucose containing and
44:11glucose free conditions.
44:12And here I'm going to focus on here this,
44:15this part.
44:15So this is the ranking of this
44:18case involved in the the the cell test.
44:21But this part is so-called
44:22the suppressor case.
44:23So suppressor case means if
44:25you suppress this suppression,
44:27it can it can make cells more.
44:29So basically the when the protein are
44:32suppressed makes cells more resistant.
44:34So the SO. So another way to think
44:36about this is the genes which are
44:39important to induce the cell deaths.
44:41OK, so that's what we're interested in here.
44:43Now you can see the number one hit here.
44:45Number one hit is SSN 711 itself.
44:48The second hit is a protein called SSS 382.
44:50So as shown here the 382 is a
44:53Chevron protein for SSS 711 function.
44:55So we identify these two protein as
44:57the top is actually really validated
44:59from you know in fact from the GNL
45:02wider screening really validate our
45:04screening right because this cell
45:06does is indeed actually induced by
45:07high expression of this transporter.
45:09So that make perfect sense.
45:11But we're more interesting in can
45:13we identify any new proteins.
45:14So the next one is a protein
45:17called NCP AP one.
45:18This protein is a part of this
45:20so-called we've regulatory complex.
45:22So this complex is function to
45:26to to regulate the up to three
45:28mediate the acting primerization
45:30and the function bouncing of this
45:32multi protein called the rack.
45:34So basically rack activates this
45:36wave record complex to promote up to
45:39three mediate effect implementation.
45:41Eventually this needs to the laminipodia
45:44formation as you know laminipodia from
45:46this web like you know structure right
45:49for the actions to really mediate.
45:51So for example the cell migration and so on.
45:54So we just to I want to validate the results.
45:57We've not called the gene didn't
45:59make cell more resistance.
46:00I just want to point out that the phenotype
46:03is not as dramatic as we knock out SSC 11.
46:06I'm going to come back to this point
46:09later but the other way to show this
46:11is if we over express this constitute
46:13active rack to promote this pathway we
46:16can also promote cell deaths and this
46:18cell death again can be rescued by
46:20the specify the the reducing regions
46:22and again the cell death does not
46:25occur in the NCK one local cells.
46:27So therefore the rack effect on
46:29the cell death is really dependent
46:31on this wave recordly complex.
46:34So all this study and other data
46:36show that basically the activation
46:38of this password rack we've somehow
46:41to promote this cell deaths,
46:43but not at the level of the SSSM 11
46:46or system uptake or NEPHI don't.
46:49I don't show the data here,
46:50but it's really to regulate the
46:53cytoskeleton structure and therefore
46:55to promote cell deaths.
46:57So I'm going to discuss a little
46:59bit how we can interpret this data.
47:01OK.
47:01But this really shows that this
47:03rack and we've rec it complex play
47:06a role in this cell deaths.
47:08So OK,
47:09so I'm going to also we kind of
47:10want to think about how we can
47:12target this cell deaths in,
47:13in, in kind of therapy, right.
47:15So the way we study this cell
47:17deaths is to culture cells in
47:19the glucose free medium, right.
47:20The other way we can do this
47:22is to use glute inhibitors,
47:23So glute glute glucose transport
47:26inhibitors to block the glucose transport
47:29and therefore mimic glucose starvation.
47:31So hopefully that can also make those cells
47:34more sensitive to to to the best of pulses.
47:37And this is indeed what we found in the cells
47:39with high expression of this transporter.
47:42And you can see with different glute
47:43inhibitors we can make cells more
47:45sensitive compared with those cells with
47:47low expression of this transporter.
47:49Conversely,
47:49if we over expressed this transporter in
47:52the in the in the low expression cell line,
47:55we can also since it has those
47:57cells increased the cell that's in
48:00response to the glute inhibitors.
48:02Furthermore, we have found this in vivo.
48:03So this was done by Xiao Wang and so
48:06we tested the PDX model with is a low
48:08or high expression of this transport.
48:11And again the glute inhibitors
48:13are more sensitive,
48:15works better in the in the PDX
48:17model with high expressions.
48:18So Randy suggested we can use
48:20glute in which to target this this
48:23tumors with high expression of
48:26this transporter as a therapeutic
48:28strategy to induce specs of pulses.
48:30And we further prove those glutin
48:32inhibitors indeed induce this type
48:34of cell diets because as a you
48:36know for example it doesn't use
48:38other cell diets induce the best
48:40by bonding and also disruption of
48:43cytoskeleton structures in the cells.
48:45So here I want to just give you a summary
48:48for the second part of my presentation.
48:50So what we found here is that in
48:52the first part of my presentation
48:54I mentioned that is transport the
48:56SSC significant important system to
48:58protect cell from for process and
49:01that benefit kind of cells because by
49:03surprise for process you can clean
49:06ability to to to to induce tumor
49:08progression metastasis so on and so forth.
49:11However,
49:11what I'm going to see for the second
49:14part of my presentation I want to
49:16say is that that comes with a cost.
49:18So many things have right have two
49:19sides where I have to you know the coin
49:21has two sides so you benefit something,
49:23you have to lose something.
49:24So the cost here is that this high
49:27expression of SS7 ivine because
49:29import a lot of system that can
49:31induce bisulfide stress and this
49:33is the mainly because of bisulfide
49:36such as system are you know toxic to
49:39the cells And under the conditions
49:41with any pH depletion such as on the
49:44glucose deprivation condition that can
49:46induce rapid cell deaths but a very
49:48different cell deaths mechanism and
49:50we can't we we termed by soft tosses.
49:54Now mechanistically we propose that
49:56this high accumulation of diazol
49:59molecules can induce a parent of
50:01diazepam bounding in the acting
50:03cytoscondin protein that can use to
50:05the collapse of the acting network
50:08and eventually this contribute
50:10to bisulfi tosis and the reason why
50:13this can contribute to that that's of
50:15tosses perhaps because those as I just
50:17mentioned that this involve this rack
50:19WRC pathway and to active up to three
50:23complex to immediate the namely protea.
50:25So namely protea form this web like you
50:28know acting structure so that perhaps
50:30can facilitated the bisulfi bounding
50:33in those status skeleton network so
50:35therefore can promote the cell deaths.
50:39So we further propose this this Oh yeah
50:41so it's just point that I just mentioned
50:43and we further propose that this can
50:45perhaps we can use this as a strategic
50:48strategy for kind of therapy you know
50:50and it's the particularly in the tumors
50:52with high expression of this SRC simulator.
50:55So one quick question for us is,
50:57so if you follow my presentation, right,
51:00so we define what is that's of course
51:03basically is glucose starvation induced
51:05cell deaths in the cell lines or in cells
51:09with high expression of s s similar,
51:11right.
51:11So this is a very specific scenario, right.
51:14But we want to see whether you know
51:16this can be broadened to other contacts,
51:18right?
51:19Because the essence of this cell
51:21that's actually is by so far stress
51:23is the high accumulation of system
51:25or other dysfile molecules.
51:26So we want to see whether we
51:28can also induce more,
51:29you know the apparent accumulation of this
51:31disulfide molecules on any other conditions,
51:33right.
51:33So we started this recently.
51:35We tested this idea in the
51:37hydrogen peroxide induced.
51:39The reason we do this is because
51:40hydrogen peroxide is also conditioned
51:42to induce oxygen stress.
51:44And so as shown here the action
51:47hydrogen peroxide can be detoxified
51:49in the cells by gluteus ion.
51:51So this converts it to the oxides
51:54of glucion and oxide Glucion
51:56called GSSG will be commonly packed
51:59glucion which consumes any pH.
52:01So we think this might have something to
52:05do with this any pH depletion which is
52:08required for the tacit pauses induction.
52:11However,
52:11the issue here is that this transporter
52:14also can generate the glucion
52:15but so therefore to protect cell
52:17from protected cell from hydrogen
52:19peroxide into cell that's.
52:21But on the other hand you actually promote
52:24because the system right conversion
52:26of assisting also consumes any pH.
52:28So this has a kind of has a opposing
52:30role potentially on the dice of pulses.
52:33So we think perhaps it's expression
52:35level depending how high the expression
52:37level of this transporter maybe have
52:39a different role in regulating the
52:41hydrogen peroxide induced to sell
52:43this that is the when there's moderate
52:46expression of this transporter.
52:48So this transporter might have a
52:50beneficial role right because in
52:52this condition the major effect here
52:54is to generate more glucose ion and
52:56then can protect cell from hydrogen
52:58peroxide induced the cell deaths and
53:01we know the cell deaths many are at
53:04pauses however in the cells with very
53:06high expression of this transporter.
53:07So the cells are overwhelmed with
53:11those assistant molecules when
53:13when the cells are captured in the
53:16hydrogen peroxide condition because now
53:18the GSSG also consumes the conversion
53:20back to GSH also consumes a lot of any pH.
53:23So under this condition the there is
53:26massive condition system so that can
53:28kill cells through by soft tosses.
53:30So I'm going to show you a couple
53:32of data to illustrate our model.
53:34So first is to see the system concentration.
53:38Recall Ernie I show you that in glucose
53:40dye vision condition there's increased
53:41the disify system concentration in the
53:43cells with over expression transport.
53:45So here we have three sets of cell
53:48lines relatively low or relatively
53:49moderate or high.
53:50So the definition here it will be a
53:53moderate will be probably increase
53:55the system uptake by fivefold and
53:57high will be more than tenfold.
53:59So we see it under the moderate condition,
54:00we don't see much system accumulation
54:03but really when you have very high
54:05expression now you'll see a massive
54:07accumulation of system concentration.
54:08Now the cell death is interesting
54:09if you capture this cells on the
54:11glucose starvation condition,
54:12you can see in regarding this is moderate
54:15or high expression of this transporter,
54:18it's always promotes this glucose
54:20starvation use the cell death which is best
54:23of process and we have high expression.
54:25I have more cell deaths now.
54:27However the patent changed a lot when
54:29we studied on the culture of the cells
54:31on the hydrogen proxide condition.
54:33So with modern over expression you
54:35can actually can protect the cells.
54:36So this is what I illustrated here because
54:39you can increase glucion biosynthesis
54:42so therefore can surprise the hydrogen
54:44peroxide and use the cell toxicity.
54:46However,
54:47the cell that you just drastically
54:48increased when you have very high
54:50expressions this transporter and
54:52that's because the best of tosses
54:53because we can show this by a number
54:55of other approaches to prove this
54:58is indeed caused by Dysol 5 bonding.
55:01So I want to end my talk by
55:03presenting a couple of key questions.
55:04I think because this is a new
55:06formal cell dies,
55:07I think that there are a number of new
55:09customers we can start in the future.
55:10For example,
55:11want to study if there's any
55:13other bouncing factors.
55:14I should only mention that AC key AP one or
55:16cause the phenotype is relatively moderate.
55:19So we think there must be other downstream
55:21effectors mediating this type of cell test.
55:24So we're very interested in starting that.
55:26And there's any performing proteins.
55:28So people study,
55:30for example,
55:31parapaulsis or necropaulsis,
55:32know that the performing protein are very,
55:35very important.
55:36So we'll want to know whether
55:38those proteins play a similar role
55:40in this type of cell test and we
55:42want to see what is threshold.
55:44So we'll talk about you know highest system
55:47Commission but really is how high is high,
55:50right.
55:50So we want to see really what is
55:52the stretch code for the Tysabad
55:54stress required for this CL test
55:56and what about the Ocneos,
55:58any other signal pathways cross talk
56:00with type of CL test, so on and so
56:03forth but not really is the what is,
56:07is the unique marker for this cell test.
56:10So we don't have a unique marker to
56:12measure this type of cell test so far.
56:14So that's really A1 important question
56:15for us to address in the future study,
56:17particularly if we want to explore this
56:20type of cell test for any therapy,
56:22you know disease treatment.
56:23So the bear market will be important for us.
56:27So with that I'm going to in my talk,
56:29I'm going to thank my name,
56:30I think I mentioned them during my
56:33presentation and some of them already
56:35left lab established their lab and also
56:37thank our collaborators and the funding,
56:39resource funding.
56:40I want to thank you for your
56:41attention and I would like to
56:42address any question if you have.
56:43Thank you.
56:44Good questions.
56:56Yes,
57:14right,
57:32right, right, right.
57:33So yeah that's a very good question.
57:34I think we haven't the systematic study this.
57:37I think there are a number of bioinformatic
57:40papers or you know genomics papers
57:42have we have done such analysis.
57:45I think I think it's not very
57:47clear for GPS for about 4-4 s s
57:50711 it is over expressed in many
57:53cancers such As for example keep
57:54one that's very good coronation.
57:56So the key prime mutant lung cancer.
57:58I think we have also done this yeah you
58:00want for papers so if you look at the
58:02TCG data set the keep one mutant non
58:05kind of cells have higher expression of
58:08SSS 711 compared with keep my wild type.
58:11Other people have shown that also
58:13over expressed in other kind of
58:14types such as P DAG and you know
58:17certainly the kidney kinds of example.
58:19So, so definitely SSS 711 has been
58:23had studied a lot and also you as you
58:25mentioned the s s 711 also undergo
58:27this transcription regulation by a
58:29number of transcription factors.
58:31So that explains why is you know
58:34should the the,
58:35the the differential expression consists.
58:37Yeah,
58:37I think the GPS 4 probably is
58:39nice understood and certainly we
58:41should do that more thoroughly.
58:43Yeah.
58:44Yes,
58:48yeah,
58:52right,
59:01right, right, right, right.
59:07Oh yeah, yeah, it's a very good question.
59:08So the question is the keep one
59:10is the loss in the non conscious
59:12union switched with RKP one.
59:14So whether the phenotype we described
59:16here has anything to do with RKP one.
59:18So in this case we have done the
59:20experiment for example in the we have
59:22done the genetic experiment in the
59:23keep 10 sorry in keep on what type
59:25not kind of cell we know called keep
59:27one and then we shoot the phenotype.
59:28So the phenotype is so therefore
59:31it's not associated with LTB one.
59:33Now she mentioned that the LTB one also
59:35has also played a role in in for a pulses.
59:38I did I don't have time to talk about here
59:41that's because LTB one can also regulate MPK.
59:44We prove to show that MPK function
59:47to to surprise for a pulses.
59:50So the air QP one and no cost the you
59:52know for example the air QP one no
59:55cost or deficient non kind of cells
59:57are more sensitive to to from process.
59:59So that has been published by other groups.
01:00:02So you see that there's the difference
01:00:04rather keep one and mute non non kind of
01:00:06cells are more resistant versus air QP
01:00:09one and no cost cells are more sensitive.
01:00:11Yeah so that it's not coordinated here.
01:00:14Yeah,
01:00:14even though the I don't understand the air
01:00:16QP 1 mutation and the keep one mutation open.
01:00:19Commutated, right. So, yeah,
01:00:20but in terms of functioning for process,
01:00:23I think it's kind of opposite.
01:00:25Yeah.
01:00:27Yes.
01:00:35Yeah,
01:00:43Right,
01:01:01right. Yeah. So whether,
01:01:12yeah, yeah. So that's a very good question.
01:01:14So I think as in one of my slides I
01:01:17mentioned rather two sides, right.
01:01:19So you use either use for process
01:01:21inhibitor or for process inducer
01:01:23to treat different diseases.
01:01:25So for cancer we use for process
01:01:27inducer but for many other diseases
01:01:28Nash you know kidney injury,
01:01:30urine to general disease to
01:01:32issue use for process inhibitor.
01:01:34So the question the you know if you use
01:01:36one actually you can actually can maybe
01:01:39induce the open damage on the other side.
01:01:41So that indeed is why important question
01:01:43I think requires more rigorous test in
01:01:46the in the in many curriculum models.
01:01:49Now generally the for process
01:01:53inhibits or for process inducer.
01:01:56So for example for process
01:01:58inhibits we tested in annual model
01:02:01itself doesn't have much effect.
01:02:03I think that the basal because the
01:02:06basal level for process in tissues are
01:02:09relatively low so therefore you just
01:02:11inhibit those are the antioxidants.
01:02:13So it doesn't have much.
01:02:14It needs to be based on the tissue,
01:02:16I mean the the the you know past
01:02:19logic analysis or based on the animal
01:02:21weight we don't see much effect.
01:02:23The for process inducer might be a
01:02:26concern because induce might induce for
01:02:29processing tumors than the normal tissues.
01:02:31So that's always the issue.
01:02:33If you think about for example chemotherapy,
01:02:35radiotherapy, right,
01:02:35you can kill cells in tumors as
01:02:38well as in normal tissues, right.
01:02:40That's why they also have all
01:02:42this side effect.
01:02:43So I think that indeed is a concern.
01:02:45So that's why we think the identified
01:02:48the specific context which tumors
01:02:50are more more vulnerable to
01:02:51fructoses might be important.
01:02:53So in this case,
01:02:54if the tumors are more vulnerable
01:02:56to for ******* the normal tissue,
01:02:58then we can use this sorry fructose
01:03:01inducer to selectively kill tumor
01:03:03cells with aspiring normal tissues.
01:03:05So that's the idea.
01:03:06Yeah,
01:03:21right. Yeah,
01:03:27Yeah. So, yeah,
01:03:28some audience asked this question.
01:03:31I think in Weibo probably would be
01:03:33difficult to mimic this glucose
01:03:35starvation because you are expert on this.
01:03:37The glucose homostasis is tightly regulated.
01:03:40So it's really difficult to see a dramatic
01:03:43decrease of glucose supply right to the,
01:03:46I mean in the systemic level.
01:03:49But what we can propose here is use
01:03:52the glute glute inhibitors to block
01:03:54the glucose optic in the into tumors
01:03:58because glute glutes expression
01:04:00is typically tumors that have high
01:04:03expression glute glucose transporter.
01:04:05So that's why people use FDG
01:04:07pad to image tumors.
01:04:08So that probably is more
01:04:10feasible than I don't know.
01:04:12They use fasting to decrease glucose
01:04:14the the level in the in the blood
01:04:16that probably is more tricky I think
01:04:18right because of the tightening
01:04:20regulated the glucose chromostasis
01:04:27that could be. Yeah. Yeah. Yeah.
01:04:32Right, right, right.
01:04:32We can probably test that. Yeah.
01:04:34Yeah. Probably more challenging.
01:04:36Yeah. I think even fasting itself
01:04:37people have proposed use fasting to
01:04:39as A1 therapeutic strategy but never
01:04:41has been moved to the clinical yet.
01:04:43Yeah, because of many other you know
01:04:46practical challenges couple minutes over.
01:04:50So I would like to thank.
01:04:54OK, thank you. Thank you.