scholarly journals DPP inhibition alters the CXCR3 axis and enhances NK and CD8+ T cell infiltration to improve anti-PD1 efficacy in murine models of pancreatic ductal adenocarcinoma

2021 ◽  
Vol 9 (11) ◽  
pp. e002837
Author(s):  
Allison A Fitzgerald ◽  
Shangzi Wang ◽  
Veena Agarwal ◽  
Emily F Marcisak ◽  
Annie Zuo ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Tumor Growth ◽  
Nk Cells ◽  
Pancreatic Ductal Adenocarcinoma ◽  
Immune Cell ◽  
Ductal Adenocarcinoma ◽  
Murine Models ◽  
Cell Content ◽  
Immune Infiltration

BackgroundPancreatic ductal adenocarcinoma (PDAC) is projected to be the second leading cause of cancer death in the USA by 2030. Immune checkpoint inhibitors fail to control most PDAC tumors because of PDAC’s extensive immunosuppressive microenvironment and poor immune infiltration, a phenotype also seen in other non-inflamed (ie, ‘cold’) tumors. Identifying novel ways to enhance immunotherapy efficacy in PDAC is critical. Dipeptidyl peptidase (DPP) inhibition can enhance immunotherapy efficacy in other cancer types; however, the impact of DPP inhibition on PDAC tumors remains unexplored.MethodsWe examined the effects of an oral small molecule DPP inhibitor (BXCL701) on PDAC tumor growth using mT3-2D and Pan02 subcutaneous syngeneic murine models in C57BL/6 mice. We explored the effects of DPP inhibition on the tumor immune landscape using RNAseq, immunohistochemistry, cytokine evaluation and flow cytometry. We then tested if BXCL701 enhanced anti-programmed cell death protein 1 (anti-PD1) efficacy and performed immune cell depletion and rechallenged studies to explore the relevance of cytotoxic immune cells to combination treatment efficacy.ResultsIn both murine models of PDAC, DPP inhibition enhanced NK and T cell immune infiltration and reduced tumor growth. DPP inhibition also enhanced the efficacy of anti-PD1. The efficacy of dual anti-PD1 and BXCL701 therapy was dependent on both CD8+ T cells and NK cells. Mice treated with this combination therapy developed antitumor immune memory that cleared some tumors after re-exposure. Lastly, we used The Cancer Genome Atlas (TCGA) to demonstrate that increased NK cell content, but not T cell content, in human PDAC tumors is correlated with longer overall survival. We propose that broad DPP inhibition enhances antitumor immune response via two mechanisms: (1) DPP4 inhibition increases tumor content of CXCL9/10, which recruits CXCR3+ NK and T cells, and (2) DPP8/9 inhibition activates the inflammasome, resulting in proinflammatory cytokine release and Th1 response, further enhancing the CXCL9/10-CXCR3 axis.ConclusionsThese findings show that DPP inhibition with BXCL701 represents a pharmacologic strategy to increase the tumor microenvironment immune cell content to improve anti-PD1 efficacy in PDAC, suggesting BXCL701 can enhance immunotherapy efficacy in ‘cold’ tumor types. These findings also highlight the potential importance of NK cells along with T cells in regulating PDAC tumor growth.

Effect of MMP9 inhibition on effector T-cell responses in a PD1-axis refractory model.

2017 ◽  
Vol 35 (7_suppl) ◽  
pp. 104-104
Author(s):  
Victoria Smith ◽  
Vladi Juric ◽  
Amanda Mikels-Vigdal ◽  
Chris O'Sullivan ◽  
Maria Kovalenko ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
T Cells ◽  
T Cell ◽  
Tumor Growth ◽  
Cell Activation ◽  
Immune Cell ◽  
Single Agent ◽  
Fold Increase ◽  
Cytotoxic T Cell

104 Background: Matrix metalloproteinase 9 (MMP9) acts via diverse mechanisms to promote tumor growth and metastasis, and is a key component of the immune-suppressive myeloid inflammatory milieu. We developed a monoclonal antibody (AB0046) that inhibits murine MMP9 and assessed its mechanism of action in immunocompetent mice as a single agent, or in combination with a murine anti-PDL1 antibody. Methods: An orthotopic, syngeneic tumor model (NeuT), which models MMP9-positive myeloid infiltrate, was utilized for efficacy and pharmacodynamic studies involving RNA and T cell receptor (TCR) sequencing, and flow cytometry. Enzymatic analyses were performed on T cell chemoattractant CXCR3 ligands (CXCL9, CXCL10, and CXCL11) which were subsequently evaluated in chemotaxis assays. Results: Anti-MMP9 treatment alone or in combination with an anti-PDL1 antibody decreased primary tumor growth as compared to IgG control-treated animals (56% vs 335% tumor growth increase, p = 0.0005) or anti-PDL1 alone. Profiling of tumors by RNA sequencing revealed that inhibition of MMP9 resulted in elevated expression of genes associated with immune cell activation pathways (Hallmark Interferon Gamma Response, FDR p < 0.001). Treatment with anti-MMP9 and anti-PDL1 antibodies decreased TCR clonality, with evidence of a more diverse TCR repertoire (p = 0.005). Immunophenotyping of tumor-associated T cells by flow cytometry showed that anti-MMP9 and anti-PDL1 co-treatment promoted a 2.8-fold increase in CD3+ cells in tumors (p = 0.01), which was associated with an increase in CD4+ T cells (3.2-fold increase; p = 0.006) and CD8+ T cells (2.8-fold increase; p = 0.013). In contrast, anti-MMP9 and combination treatment resulted in a decrease in tumor-associated regulatory T cells (CD25+ FoxP3+ cells, p = 0.04). MMP9 cleavage of T cell chemoattractant ligands in vitro rendered them functionally inactive for recruitment of activated primary human effector T cells. Conclusions: Inhibition of MMP9 reduces tumor burden and promotes cytotoxic T cell infiltration in a PD1-axis refractory mouse model. The combination of nivolumab and GS-5745, a humanized anti-MMP9 inhibitory antibody, is currently being evaluated in gastric cancer (NCT02864381).

scholarly journals Pancreatic cancer cells assemble a CXCL12-keratin 19 coating to resist immunotherapy

2019 ◽  
Author(s):  
Zhikai Wang ◽  
Ran Yan ◽  
Jiayun Li ◽  
Ya Gao ◽  
Philip Moresco ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Pancreatic Ductal Adenocarcinoma ◽  
Cancer Cells ◽  
Checkpoint Inhibitors ◽  
Transglutaminase 2 ◽  
Ductal Adenocarcinoma ◽  
Cancer Associated Fibroblast ◽  
Pancreatic Cancer Cells ◽  
Keratin 19

AbstractHow pancreatic ductal adenocarcinoma (PDA) cells stimulate CXCR4 to exclude T cells and resist T cell checkpoint inhibitors is not known. Here, we find that CXCL12, the ligand for CXCR4 that is produced by the cancer-associated fibroblast, “coats” human PDA and colorectal cancer cells as covalent heterodimers with keratin 19 (KRT19). Modeling the formation of the heterodimer with three proteins shows that KRT19 binds CXCL12 and transglutaminase-2 (TGM2), and that TGM2 converts the reversible KRT19-CXCL12 complex into a covalent heterodimer. We validate this model by showing that cancer cells in mouse PDA tumors must express KRT19 and TGM2 to become coated with CXCL12, exclude T cells, and resist immunotherapy with anti-PD-1 antibody. Thus, PDA cells have a cell-autonomous means by which they capture CXCL12 to mediate immune suppression, which is potentially amenable to therapy.One Sentence SummaryCancer cells in pancreatic ductal adenocarcinoma use transglutaminase-2 to assemble a coating comprised of covalent CXCL12-keratin 19 heterodimers that excludes T cells and mediates resistance to inhibition of the PD-1 T cell checkpoint.

500 P2RX7 agonist treatment boosts the ability of IL-12-activated CD8+ T cells to infiltrate and control murine melanoma

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A535-A535
Author(s):  
Kelsey Wanhainen ◽  
Stephen Jameson ◽  
Henrique Borges Da Silva
Keyword(s):  
T Cells ◽  
T Cell ◽  
Tumor Growth ◽  
Cd8 T Cells ◽  
Mitochondrial Respiration ◽  
Immune Cell ◽  
List Type ◽  
Memory Cd8 T Cells ◽  
And Control

BackgroundExtracellular adenosine triphosphate (eATP) is a ‘danger signal’ used to sense cellular damage, and recognized by purinergic receptors in mammals. Among those receptors, P2RX7 is preferentially expressed in immune cells. Notably, we recently discovered that P2RX7 is crucial for the generation and maintenance of long-lived tissue-resident and circulating memory CD8+ T cells.1 2 CD8+ T cell function is fundamental for tumor control, and therapies to harness protective CD8+ T cells that overcome exhaustion are currently in the limelight of anticancer strategies. Given our previous data, and the fact that eATP is abundantly present inside the melanoma microenvironment, we tested whether (a) P2RX7 is required for activated CD8+ T cells to infiltrate and control melanoma upon adoptive cell therapy, and (b) P2RX7 agonism can boost the anticancer capacity of CD8+ T cells.Methods(a) We in vitro-activated WT or P2rx7-/- CD8+ T cells (transgenic for the LCMV epitope gp33-P14 or for the ovalbumin SIINFEKL peptide-OTI) with anti-CD3/CD28/IL-2, ± IL-12, for 72h. Cells were adoptively transferred (single transfer of WT or P2rx7-/- cells) into mice with 7 days after subcutaneous transfer of B16 melanoma encoding gp33 or SIINFEKL. We tracked tumor growth until 60 days or at the appropriate endpoint. In some experiments, we sacrificed recipient mice 7 days after adoptive T cell transfer for immune cell phenotyping. Some parameters (cytokine production, mitochondrial respiration via Seahorse) were measured in in vitro-activated cells. (b) WT and P2rx7-/- cells were activated with anti-CD3/anti-CD28/IL-2, ± Bz-ATP, a P2RX7 agonist. Tumor growth was tracked over time until 60 days or at the appropriate endpoint.ResultsWT and P2RX7-deficient (P2rx7-/-) CD8+ T cells in the absence of IL-12 do not differ in tumor infiltration and/or control. However, P2rx7-/- CD8+ T cells activated in response to IL-12 tertiary stimulus do not control B16 melanomas as well as their WT counterparts. Phenotypically, IL-12-P2rx7-/- CD8+ T cells do not profoundly differ from IL-12-WT CD8+ T cells, except for diminished mitochondrial respiration levels in vitro, and diminished mitochondrial membrane potential (e.g. mitochondrial health) among tumor-infiltrating cells. Strikingly, Bz-ATP treatment increased the mitochondrial activity of WT CD8+ T cells in vitro and in vivo and led to increased B16 infiltration and control, in a P2RX7-dependent manner.ConclusionsWe are currently studying the mechanisms behind the ability of P2RX7 agonists to increase the antitumor function of CD8+ T cells; these are promising results that can lead to a new alternative in immune cell therapies against melanoma.AcknowledgementsWe would like to thank Jane Ding and Lily Qian for technical assistance, and Kristin Hogquist for scientific input.Ethics ApprovalThis study was approved by the IACUC board at the University of Minnesota (IACUC number A3456-01)ReferencesBorges da Silva H, Beura LK, Wang H, Hanse EA, Gore R, Scott MC, Walsh DA, Block KE, Fonseca R, Yan Y, Hippen KL, Blazar BR, Masopust D, Kelekar A, Vulchanova L, Hogquist KA, Jameson SC. The purinergic receptor P2RX7 directs metabolic fitness of long-lived memory CD8+ T cells. Nature. 2018; 559(7713):264–268.Borges da Silva H, Peng C, Wang H, Wanhainen KM, Ma C, Lopez S, Khoruts A, Zhang N, Jameson SC. Extracellular ATP sensing via P2RX7 promotes CD8+ tissue-resident memory T cells by enhancing TGF-β sensitivity. Immunity 2020;53(1):158–171.

scholarly journals 659 T cell receptor exchange by zygote engineering results in physiological T cell responses for therapeutic use in pancreatic ductal adenocarcinoma

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A687-A687
Author(s):  
Meagan Rollins ◽  
Jackson Raynor ◽  
Ebony Miller ◽  
Ellen Spartz ◽  
Walker Lahr ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Pancreatic Ductal Adenocarcinoma ◽  
Animal Studies ◽  
Tumor Stroma ◽  
Cell Receptor ◽  
Ductal Adenocarcinoma ◽  
University Of Minnesota ◽  
T Cell Therapy ◽  
High Affinity

BackgroundPancreatic ductal adenocarcinoma (PDA) is a lethal malignancy characterized by a highly suppressive tumor microenvironment. Despite this, engineered T cell therapy has promise for effectively targeting PDA. To identify the underlying mechanisms of antigen-specific engineered T cell immunosuppression in PDA, we create novel TCR knock-in mouse models for a robust and standardized source of naïve mesothelin (Msln)-specific T cells.MethodsSpecifically, we integrate two murine mesothelin-specific TCRs into the physiologic Trac locus in primary murine T cells and zygotes using CRISPR/Cas9 and rAAV expressing the TCR DNA. Simultaneously using CRISPR/Cas9, Msln was disrupted to circumvent T cell tolerance.ResultsThis strategy resulted in the rapid generation of homozygous TCR Trac knock-in mice and with homozygous null mutations in Msln. In these TCR-exchanged (TRex) mice, most T cells expressed the 1045 (high affinity) or 7431 (low affinity) as determined by tetramer staining. TRex T cells exhibit a naïve phenotype and rapidly differentiate into effector T cells upon antigenic stimulation. While the high affinity 1045 TCR elicits function in CD4 T cells, the lower affinity 7431 T cells exhibit a higher functional avidity and less TCR downregulation when antigen is limiting. Historical TCR transgenic T cells, in which the TCR is randomly integrated into the genome, exhibit increased PD1, CD25, and CD69, decreased functionality, and a bias to CD25-Foxp3+ Treg as compared to T cells from TRex mice. Further, TCR Trac integration in primary T cells retain superior function following repetitive antigenic stimulations retrovirally transduced T cells. Adoptive transfer of 1045 TRex T cells significantly prolongs survival of mice bearing autochthonous PDA. When combined with a vaccine, 1045 TRex T cells cause involution of the fibroinflammatory tumor stroma.ConclusionsIn sum, we rapidly generate mice that physiologically express the desired TCR, circumventing the shortcomings of standard T cell engineering strategies and TCR transgenic models.Ethics ApprovalUniversity of Minnesota Institutional Animal Care and Use Committee approved all animal studies to Dr. Ingunn Stromnes (2005-38115A.) Generation of TCR knockin (KI) animals was performed in the Mouse Genetic Laboratory at the University of Minnesota.

scholarly journals Resistance of Natural Killer and T Cells to Venetoclax Allows for Combination Treatment with Cancer Immunotherapy Agents

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 1118-1118 ◽  
Author(s):  
Elisabeth A Lasater ◽  
An D Do ◽  
Luciana Burton ◽  
Yijin Li ◽  
Erin Williams ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
Nk Cells ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Immune Cell ◽  
Single Agent ◽  
Employment Equity ◽  
Equity Ownership

Abstract Introduction: Intrinsic apoptosis is regulated by the BCL-2 family of proteins, which consists of both anti-apoptotic (BCL-2, BCL-XL, MCL-1) and pro-apoptotic (BIM, BAX, BAK, BAD) proteins. Interaction between these proteins, as well as stringent regulation of their expression, mediates cell survival and can rapidly induce cell death. A shift in balance and overexpression of anti-apoptotic proteins is a hallmark of cancer. Venetoclax (ABT-199/GDC-0199) is a potent, selective small molecule BCL-2 inhibitor that has shown preclinical and clinical activity across hematologic malignancies and is approved for the treatment of chronic lymphocytic leukemia with 17p deletion as monotherapy and in combination with rituximab. Objective: To investigate the effects of BCL-2 inhibition by venetoclax on viability and function of immune-cell subsets to inform combinability with cancer immunotherapies, such as anti-PD-L1. Methods and Results: B cells, natural killer (NK) cells, CD4+ T cells, and CD8+ T cells in peripheral blood mononuclear cells (PBMCs) from healthy donors (n=3) were exposed to increasing concentrations of venetoclax that are clinically achievable in patients, and percentage of live cells was assessed by flow-cytometry using Near-IR cell staining. B cells were more sensitive to venetoclax (IC50 of ~1nM) than CD8+ T cells (IC50 ~100nM), NK cells (IC50 ~200nM), and CD4+ T cells (IC50 ~500nM) (Figure A). CD8+ T-cell subset analysis showed that unstimulated naive, but not memory cells, were sensitive to venetoclax treatment (IC50 ~30nM and 240nM, respectively). Resistance to venetoclax frequently involves compensation by other BCL-2 family proteins (BCL-XL and MCL-1). As assessed by western blot in PBMCs isolated from healthy donors (n=6), BCL-XL expression was higher in NK cells (~8-fold) and CD4+ and CD8+ T cells (~2.5-fold) than in B cells (1X). MCL-1 protein expression was higher only in CD4+ T cells (1.8-fold) relative to B cells. To evaluate the effect of venetoclax on T-cell function, CD8+ T cells were stimulated ex vivo with CD3/CD28 beads, and cytokine production and proliferation were assessed. Venetoclax treatment with 400nM drug had minimal impact on cytokine production, including interferon gamma (IFNg), tumor necrosis factor alpha (TNFa), and IL-2, in CD8+ effector, effector memory, central memory, and naïve subsets (Figure B). CD8+ T-cell proliferation was similarly resistant to venetoclax, as subsets demonstrated an IC50 >1000nM for venetoclax. Taken together, these data suggest that survival of resting NK and T cells in not impaired by venetoclax, possibly due to increased levels of BCL-XL and MCL-1, and that T-cell activation is largely independent of BCL-2 inhibition. To evaluate dual BCL-2 inhibition and PD-L1 blockade, the syngeneic A20 murine lymphoma model that is responsive to anti-PD-L1 treatment was used. Immune-competent mice bearing A20 subcutaneous tumors were treated with clinically relevant doses of venetoclax, murine specific anti-PD-L1, or both agents. Single-agent anti-PD-L1 therapy resulted in robust tumor regression, while single-agent venetoclax had no effect. The combination of venetoclax and anti-PD-L1 resulted in efficacy comparable with single-agent anti-PD-L1 (Figure C), suggesting that BCL-2 inhibition does not impact immune-cell responses to checkpoint inhibition in vivo. These data support that venetoclax does not antagonize immune-cell function and can be combined with immunotherapy targets. Conclusions: Our data demonstrate that significant venetoclax-induced cell death at clinically relevant drug concentrations is limited to the B-cell subset and that BCL-2 inhibition is not detrimental to survival or activation of NK- or T-cell subsets. Importantly, preclinical mouse models confirm the combinability of BCL-2 and PD-L1 inhibitors. These data support the combined use of venetoclax and cancer immunotherapy agents in the treatment of patients with hematologic and solid tumor malignancies. Figure Figure. Disclosures Lasater: Genentech Inc: Employment. Do:Genentech Inc: Employment. Burton:Genentech Inc: Employment. Li:Genentech Inc: Employment. Oeh:Genentech Inc: Employment. Molinero:Genentech Inc: Employment, Equity Ownership, Patents & Royalties: Genentech Inc. Penuel:Genentech Inc: Employment. Sampath:Genentech Inc: Employment. Dail:Genentech: Employment, Equity Ownership. Belvin:CytomX Therapeutics: Equity Ownership. Sumiyoshi:Genentech Inc: Employment, Equity Ownership. Punnoose:Roche: Equity Ownership; Genentech Inc: Employment. Venstrom:Genentech Inc: Employment. Raval:Genentech Inc: Consultancy, Employment, Equity Ownership.

scholarly journals Identification of Prognostic and Therapeutic Biomarkers among FAM83 Family Members for Pancreatic Ductal Adenocarcinoma

2021 ◽  
Vol 2021 ◽  
pp. 1-21
Author(s):  
Zuyi Ma ◽  
Zixuan Zhou ◽  
Hongkai Zhuang ◽  
Zhenchong Li ◽  
Zuguang Ma ◽  
...  
Keyword(s):  
T Cell ◽  
Pancreatic Ductal Adenocarcinoma ◽  
Prognostic Value ◽  
Immune Cell ◽  
Sequence Similarity ◽  
Cell Infiltration ◽  
Ductal Adenocarcinoma ◽  
Advanced Tumor Stage ◽  
Mhc Molecules ◽  
Advanced Tumor

Family with sequence similarity 83 (FAM83) members were shown recently to have oncogenic effect in a variety of cancer types, but the biological roles and prognostic value of FAM83 family in pancreatic ductal adenocarcinoma remain unknown. In the current study, the clinical significance and molecular function of the FAM83 family were assessed by multiple bioinformatics analysis. Besides, potential associations between differentially expressed genes (DEGs) of FAM83 family and antitumor immunity were evaluated using TIMER and TISIDB analyses. As the results show, FAM83A, FAM83D, FAM83E, and FAM83H were significantly upregulated in PDAC and were identified as DEGs. Higher expression of FAM83A, FAM83B, FAM83D, FAM83E, and FAM83H were associated with advanced tumor stage or worse patient prognosis. Importantly, the overexpression of DEGs was found to be significantly correlated with activated KRAS and loss of SMAD4, which are important drivers for PDAC. Further, FAM83A, FAM83D, and FAM83H were associated with CD8+ T cell, Gamma Delta T cell, and CD4+ T cell infiltration in PDAC and FAM83H was found closely correlated with some immunomodulators including immunoinhibitors, immunostimulators, and MHC molecules. In conclusion, FAM83A, FAM83D, FAM83E, and FAM83H have significant prognostic value in PDAC and they may play important roles in regulating tumor progression and the immune cell infiltration.

scholarly journals Immune responses in pancreatic cancer may be restricted by prevalence of activated regulatory T-cells, dysfunctional and senescent T-cells

2020 ◽  
Author(s):  
Shivan Sivakumar ◽  
Enas Abu-Shah ◽  
David J Ahern ◽  
Edward H Arbe-Barnes ◽  
Nagina Mangal ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
T Cells ◽  
T Cell ◽  
Single Cell ◽  
Pancreatic Ductal Adenocarcinoma ◽  
Regulatory T Cell ◽  
Rational Design ◽  
Tumour Microenvironment ◽  
Human Pancreatic Cancer ◽  
Ductal Adenocarcinoma

AbstractObjectivePancreatic cancer has the worst prognosis of any human malignancy and leukocyte infiltration is a major prognostic marker of the disease. As current immunotherapies confer negligible survival benefits, there is a need to better characterise leukocytes in pancreatic cancer to identify better therapeutic strategies.DesignIn this study, a multi-parameter mass-cytometry analysis was performed on 32,000 T-cells from eight human pancreatic cancer patients. Single-cell RNA sequencing dataset analysis was performed on a cohort of 24 patients. Multiplex immunohistochemistry imaging and spatial analysis were performed to map immune infiltration into the tumour microenvironment.ResultsRegulatory T-cell populations demonstrated highly immunosuppressive states with high TIGIT, ICOS and CD39 expression. CD8+ T-cells were found to be either in senescence or an exhausted state. The exhausted CD8 T-cells had low PD-1 expression but high TIGIT and CD39 expression. These findings were corroborated in an independent pancreatic cancer single-cell RNA dataset from 24 patients.ConclusionsThese data suggest that T-cells are major players in the suppressive microenvironment of pancreatic cancer. Our work identifies novel therapeutic targets that should form the basis for rational design of a new generation of clinical trials in pancreatic ductal adenocarcinoma.Statement of SignificanceThis study elucidates the T-cell phenotypes in pancreatic ductal adenocarcinoma (PDAC). T-cells potentiate immune-suppression through an activated regulatory T-cell population expressing high TIGIT, ICOS and CD39. CD8+ T-cells were primarily senescent or TIGIT+ exhausted, but with minimal PD-1 expression. These findings propose new immunotherapy targets for PDAC.

Gasdermin C as a potential prognostic biomarker and its correlation with immune infiltration in pancreatic ductal adenocarcinoma.

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. e16256-e16256
Author(s):  
Xianghou Xia ◽  
Yang Yu ◽  
Hongjian Yang ◽  
Dehong Zou ◽  
Canming Wang ◽  
...  
Keyword(s):  
Pancreatic Ductal Adenocarcinoma ◽  
Cancer Cells ◽  
Prognostic Value ◽  
Immune Cell ◽  
Prognostic Significance ◽  
High Expression ◽  
Ductal Adenocarcinoma ◽  
Immune Infiltration ◽  
Kaplan Meier ◽  
Kaplan Meier Plotter

e16256 Background: Although pyroptosis is critical for macrophages against pathogen infection, its role in cancer cells remains elusive. GSDMC is a pyroptosis executioner newly identified in cancer cells and have been shown to facilitate inflammatory tumor death. However, the expression of GSDMC in Pancreatic Ductal Adenocarcinoma (PDAC), its prognostic significance and possible impact on reshaping tumor immune microenviroment in PDAC is still unknown. Methods: We investigated the expression level of GSDMC using TNM plotter with TCGA and GTEx databases, the prognostic value of GSDMC in PDAC using Kaplan-Meier plotter with TCGA, GTEx and TCGA databases. The correlations between GSDMC and immune infiltration in PDAC were calculated using TIMER2.0 and TIDE with TCGA database. We further validated the prognostic value of GSDMC with immunohistochemistry(IHC) staining on a tissue microarray of 172 cases of PDAC patients receiving treatment in our institution. Correlations between expression of GSDMC and tumor infiltration lymphacytes(TILs) cells were also analyzed on tissue samples of those 172 PDAC patients. Results: TNM plotter analysis shows that the expression of GSDMC in PDAC tumor tissue is 10.49 folds higher than it is in pancreatic normal tissues (p = 8.86*e-56). Results from Kaplan-Meier plotter analysis shows high expression of GSDMC is significantly correlated with poorer overall survival(OS), HR = 1.8(1.19−2.71) logrank P = 0.004 and shorter relapse free survival (RFS), HR = 4.6(1.94−10.88), Logrank P = 0.00014 in PDAC. Analysis with TIMER2.0 and TIDE platform shows that expression of GSDMC is positively correlated with immunosuppressive cells, Cancer Associated Fiberblast (CAF) and Meyloid Derived Tumor Suprresso Cells(MDTSC). IHC staining analysis results is also consistent with aformentioned bioinformatic analysis, showing that high GSDMC expression correlated with shorter OS and reduced Tils infiltration. Conclusions: Our findings suggest that high expression of GSDMC is related to poor prognosis and compromised immune cell infiltration in PDAC. GSDMC holds promise for serving as a valuable prognostic marker and therapeutic target in PDAC.

Use of gastrin vaccine to increase gamma-delta and NKT cells and alter pancreas tumor microenvironment to improve survival.

2020 ◽  
Vol 38 (4_suppl) ◽  
pp. 696-696
Author(s):  
Jill P Smith ◽  
Nicholas Osborne ◽  
Rebecca Sundseth ◽  
Hong Cao ◽  
Martha D Gay ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
T Cells ◽  
T Cell ◽  
Tumor Growth ◽  
Immune Cell ◽  
Nkt Cells ◽  
Cell Phenotype ◽  
Double Negative ◽  
Gamma Delta ◽  
Pancreatic Cancer Cells

696 Background: Pancreatic cancer (PC) has been called a “cold” tumor as it responds poorly to immune-based therapies. Strategies to render PC susceptible to immunotherapy are under investigation by methods that alter immune cell signatures such as increasing the population of double negative CD4-CD8-T-cells, or changing the polarization of tumor-associated macrophages (TAMs). Our current aim was to determine if a gastrin vaccine, Polyclonal Antibody Stimulator (PAS) influences double negative T-cell phenotype and polarization of TAMs to improve survival of PC. Methods: Two cohorts of C57BL/6 mice were injected either sc or orthotopically with syngeneic mT3 murine pancreatic cancer cells. After 1 week, groups were treated with PBS; PAS (100μg); PD-1 antibody (150μg); or the combination of PAS and PD-1 Ab. PAS was given ip at weeks 0, 1 and 3. Anti-PD-1 was given on days 0, 4, 8, 15 and 21. Spleens were collected from the sc experiment for T-cell surface analysis by flow cytometry. Orthotopic tumors were measured for growth rate, metastases, and stained for M1 (inos) and M2 (arginase) polarized TAMs, and mouse survival was analyzed. Results: PAS therapy increased expression of double negative T-cells. The percentage of gamma-delta T-cells in the (CD3+/CD4−/CD8−/CD44−/CD62L−) TEMRA subpopulation of mice treated with PAS or combinations of PAS with PD-1 Ab were increased approximately 40% compared to PBS-treated controls or PD-1 Ab-treated mice. NKT cells from PAS-vaccinated mice were 2.5-fold higher than controls. M2+ TAMS were significantly decreased in tumors of PAS treated mice compared to PBS treated mice (p = 0.017). PAS monotherapy resulted in a nearly 10-fold increase in M1 TAMs relative to controls (p = 0.002). PAS monotherapy decreased tumor metastases by 69% and prolonged survival. Primary tumor growth decreased with PAS in combination with PD-1 Ab (p=0.0025). Conclusions: PAS decreases PC tumor growth and metastases by increasing CD4-CD8-, gamma-delta, and NKT T-cell populations. Furthermore, PAS monotherapy significantly increases M1 and decreases M2 TAMs. These immune cell changes with PAS vaccination may render tumors more susceptible to other cancer therapies and improve survival.

Sign in / Sign up

Export Citation Format

Share Document