Metastasis is the leading cause of cancer-related deaths. But despite much effort in elucidating the molecularmechanismsunderlyingmetastasis,thereisstillmuchthatremainsunknownandunexplored.Inmany solid tumors, metastasis is closely associated with an epithelial-to-mesenchymal transition (EMT), a form of cellular plasticity by which stationary epithelial cells acquire the motile, invasive phenotypes reminiscent of fibroblasts.AndwhileEMTresultsinmanytumorcell-intrinsicchanges,suchchangesarealsoknowntoalter thetumormicroenvironment(TME)inwaysthatfacilitatetumorcellinvasionintothebloodstreamandultimately metastasis. Thus, to define the molecular changes that occur during EMT in vivo, our lab performed whole transcriptomic analysis on sorted epithelial and mesenchymal tumor cells that were harvested from a well- establishedgeneticmousemodelofspontaneouspancreaticductaladenocarcinoma(PDA).Amongthegenes thatweremostsignificantlyupregulatedinmesenchymalcellswasSerping1,whichencodesthehepatocyte- derived plasma protease inhibitor C1-inhibitor (C1-INH). Intriguingly, our preliminary results demonstrate a possible role for tumor-derived C1-INH in the growth and vascularization of mesenchymal PDA tumors. Furthermore,recentstudieshaveshownthatcomplementfactorC1Q,whosedissociationfromthecomplement cascade depends on C1-INH, promotes angiogenesis in the context of wound healing, as well as melanoma progression. Based on our preliminary data and these newer studies, we hypothesize that C1-INH is upregulated in PDA cells during EMT to promote angiogenesis and tumor progression in a C1Q- dependentmanner.Inthisproposal,weprovidedetailsoftwoaimstotestthishypothesis.Briefly,inAim1,we willmoredeeplyinvestigatetheroleoftumor-derivedC1-INHinangiogenesisbyperforminggeneticgainand loss of function studies in murine PDA cells and using standard in vitro and in vivo angiogenesis assays to determine C1-INH?s effects on endothelial cell proliferation, migration, and differentiation, as well as the functional integrity of intratumoral blood vessels. We will also dissect the molecular mechanism of C1-INH in PDAprogressionbyinvestigatingitsfunctionaldependenciesonC1Q.SinceC1-INHwasoriginallyfoundtobe enrichedinthemesenchymalstate,wewillalsoinvestigateitspotentialroleinpromotingmetastasis.Thus,in Aim2,wewilldeterminewhethertumor-derivedC1-INHisnecessaryformetastasisbyemployinganorthotopic transplantationmodelandmonitoringdifferentstagesofthemetastaticcascade,fromtumorcelldissemination to metastatic colonization. The completed aims of this proposal ? which represents the first functional investigationofC1-INHincancer?ultimatelyseektounderstandhowcancercellsinfluencetheTMEtofacilitate tumorgrowthandmetastasis,andmayprovideaspringboardforfuturetherapeuticapplicationanddiscovery.

Public Health Relevance

Metastasisistheleadingcauseofcancer-relateddeaths,andisdrivenbychangesinbothtumorcellsandtheir surrounding microenvironment. We had previously found that the secreted molecule C1-inhibitor (C1-INH) is upregulatedbypancreaticcancercellsacquiringmoreinvasiveandpro-metastaticproperties,andthatC1-INH isimportantforpromotingtumorgrowthandintratumoralvascularization.Basedonthesefindings,Iproposeto investigatethemechanismsbywhichC1-INHfacilitatestumorprogressionandmetastasisinpancreaticcancer, representingthefirstfunctionalstudyofthismoleculeinanycancer-relatedcontext.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Individual Predoctoral NRSA for M.D./Ph.D. Fellowships (ADAMHA) (F30)
Project #
5F30CA224970-03
Application #
9842279
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Damico, Mark W
Project Start
2018-03-01
Project End
2021-02-28
Budget Start
2020-03-01
Budget End
2021-02-28
Support Year
3
Fiscal Year
2020
Total Cost
Indirect Cost
Name
University of Pennsylvania
Department
Type
Schools of Medicine
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104