scholarly journals DFMO Improves Survival and Increases Immune Cell Infiltration in Association with MYC Downregulation in the Pancreatic Tumor Microenvironment

2021 ◽  
Vol 22 (24) ◽  
pp. 13175
Author(s):  
Sai Preethi Nakkina ◽  
Sarah B. Gitto ◽  
Jordan M. Beardsley ◽  
Veethika Pandey ◽  
Michael W. Rohr ◽  
...  

Pancreatic ductal adenocarcinoma (PDAC) has an extremely poor five-year survival rate of less than 10%. Immune suppression along with chemoresistance are obstacles for PDAC therapeutic treatment. Innate immune cells, such as tumor-associated macrophages, are recruited to the inflammatory environment of PDAC and adversely suppress cytotoxic T lymphocytes. KRAS and MYC are important oncogenes associated with immune suppression and pose a challenge to successful therapies. Here, we targeted KRAS, through inhibition of downstream c-RAF with GW5074, and MYC expression via difluoromethylornithine (DFMO). DFMO alone and with GW5074 reduced in vitro PDAC cell viability. Both DFMO and GW5074 showed efficacy in reducing in vivo PDAC growth in an immunocompromised model. Results in immunocompetent syngeneic tumor-bearing mice showed that DFMO and combination treatment markedly decreased tumor size, but only DFMO increased survival in mice. To further investigate, immunohistochemical staining showed DFMO diminished MYC expression and increased tumor infiltration of macrophages, CD86+ cells, CD4+ and CD8+ T lymphocytes. GW5074 was not as effective in modulating the tumor infiltration of total CD3+ lymphocytes or tumor progression and maintained MYC expression. Collectively, this study highlights that in contrast to GW5074, the inhibition of MYC through DFMO may be an effective treatment modality to modulate PDAC immunosuppression.

2016 ◽  
Vol 85 (3) ◽  
Author(s):  
Luis A. Vega ◽  
Kayla M. Valdes ◽  
Ganesh S. Sundar ◽  
Ashton T. Belew ◽  
Emrul Islam ◽  
...  

ABSTRACTAs an exclusively human pathogen,Streptococcus pyogenes(the group A streptococcus [GAS]) has specifically adapted to evade host innate immunity and survive in multiple tissue niches, including blood. GAS can overcome the metabolic constraints of the blood environment and expresses various immunomodulatory factors necessary for survival and immune cell resistance. Here we present our investigation of one such factor, the predicted LysR family transcriptional regulator CpsY. The encoding gene,cpsY, was initially identified as being required for GAS survival in a transposon-site hybridization (TraSH) screen in whole human blood. CpsY is homologous with transcriptional regulators ofStreptococcus mutans(MetR),Streptococcus iniae(CpsY), andStreptococcus agalactiae(MtaR) that regulate methionine transport, amino acid metabolism, resistance to neutrophil-mediated killing, and survivalin vivo. Our investigation indicated that CpsY is involved in GAS resistance to innate immune cells of its human host. However, GAS CpsY does not manifest thein vitrophenotypes of its homologs in other streptococcal species. GAS CpsY appears to regulate a small set of genes that is markedly different from the regulons of its homologs. The differential expression of these genes depends on the growth medium, and CpsY modestly influences their expression. The GAS CpsY regulon includes known virulence factors (mntE,speB,spd,nga[spn],prtS[SpyCEP], andsse) and cell surface-associated factors of GAS (emm1,mur1.2,sibA[cdhA], andM5005_Spy0500). Intriguingly, the loss of CpsY in GAS does not result in virulence defects in murine models of infection, suggesting that CpsY function in immune evasion is specific to the human host.


BMC Cancer ◽  
2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Guoping Ding ◽  
Tao Shen ◽  
Chen Yan ◽  
Mingjie Zhang ◽  
Zhengrong Wu ◽  
...  

Abstract Background Pancreatic cancer is characterized by a highly immunosuppressive tumor microenvironment and evasion of immune surveillance. Although programmed cell death 1 receptor (PD-1) blockade has achieved certain success in immunogenic cancers, the responses to the PD-1 antibody are not effective or sustained in patients with pancreatic cancer. Methods Firstly, PD-1 expressions on peripheral CD8+ T-lymphocytes of patients with pancreatic cancer and healthy donors were measured. In in vitro study, peripheral T-lymphocytes were isolated and treated with nivolumab and/or interferon-γ, and next, PD-1-blockade effects, proliferations, cytokine secretions and cytotoxic activities were tested after different treatments. In in vivo study, mice bearing subcutaneous pancreatic cancer cell lines were treated with induced T-lymphocytes and tumor sizes were measured. Results PD-1 protein expression is increased on peripheral CD8+ T cells in patients with pancreatic ductal adenocarcinoma compared with that in health donor. PD-1 expression on CD8+ T-lymphocytes was decreased by nivolumab in a concentration-dependent manner in vitro. IFN-γ could directly down-regulate expression of PD-1 in vitro. Furthermore, the combination therapy of nivolumab and IFN-γ resulted in greatest effect of PD-1-blockde (1.73 ± 0.78), compared with IFN-γ along (18.63 ± 0.82) and nivolumab along (13.65 ± 1.22). Moreover, the effects of nivolumab plus IFN-γ largest promoted the T-lymphocytes function of proliferations, cytokine secretions and cytotoxic activities. Most importantly, T-lymphocytes induced by nivolumab plus IFN-γ presented the best repression of tumor growth. Conclusions IFN-γ plus a PD-1-blockading agent could enhance the immunologic function and might play a crucial role in effective adoptive transfer treatments of pancreatic cancer.


2014 ◽  
Vol 21 (11) ◽  
pp. 1550-1559 ◽  
Author(s):  
Benjamin J. Koestler ◽  
Sergey S. Seregin ◽  
David P. W. Rastall ◽  
Yasser A. Aldhamen ◽  
Sarah Godbehere ◽  
...  

ABSTRACTThe bacterial second messenger cyclic di-GMP (c-di-GMP) stimulates inflammation by initiating innate immune cell recruitment and triggering the release of proinflammatory cytokines and chemokines. These properties make c-di-GMP a promising candidate for use as a vaccine adjuvant, and numerous studies have demonstrated that administration of purified c-di-GMP with different antigens increases protection against infection in animal models. Here, we have developed a novel approach to produce c-di-GMP inside host cells as an adjuvant to exploit a host-pathogen interaction and initiate an innate immune response. We have demonstrated that c-di-GMP can be synthesizedin vivoby transducing a diguanylate cyclase (DGC) gene into mammalian cells using an adenovirus serotype 5 (Ad5) vector. Expression of DGC led to the production of c-di-GMPin vitroandin vivo, and this was able to alter proinflammatory gene expression in murine tissues and increase the secretion of numerous cytokines and chemokines when administered to animals. Furthermore, coexpression of DGC modestly increased T-cell responses to aClostridium difficileantigen expressed from an adenovirus vaccine, although no significant differences in antibody titers were observed. This adenovirus c-di-GMP delivery system offers a novel method to administer c-di-GMP as an adjuvant to stimulate innate immunity during vaccination.


Blood ◽  
2007 ◽  
Vol 110 (13) ◽  
pp. 4278-4284 ◽  
Author(s):  
Gerben Bouma ◽  
Siobhan Burns ◽  
Adrian J. Thrasher

The Wiskott-Aldrich syndrome (WAS) is characterized by defective cytoskeletal dynamics affecting multiple immune cell lineages, and leading to immunodeficiency and autoimmunity. The contribution of dendritic cell (DC) dysfunction to the immune dysregulation has not been defined, although both immature and mature WAS knockout (KO) DCs exhibit significant abnormalities of chemotaxis and migration. To exclude environmental confounders as a result of WAS protein (WASp) deficiency, we studied migration and priming activity of WAS KO DCs in vivo after adoptive transfer into wild-type recipient mice. Homing to draining lymph nodes was reduced and WAS KO DCs failed to localize efficiently in T-cell areas. Priming of both CD4+ and CD8+ T lymphocytes by WAS KO DCs preloaded with antigen was significantly decreased. At low doses of antigen, activation of preprimed wild-type CD4+ T lymphocytes by WAS KO DCs in vitro was also abrogated, suggesting that there is a threshold-dependent impairment even if successful DC–T cell colocalization is achieved. Our data indicate that intrinsic DC dysfunction due to WASp deficiency directly impairs the T-cell priming response in vivo, most likely as a result of inefficient migration, but also possibly influenced by suboptimal DC-mediated cognate interaction.


Cancers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3816
Author(s):  
Loryn Holokai ◽  
Jayati Chakrabarti ◽  
Joanne Lundy ◽  
Daniel Croagh ◽  
Pritha Adhikary ◽  
...  

Purpose: Pancreatic ductal adenocarcinoma (PDAC) has the lowest five-year survival rate of all cancers in the United States. Programmed death 1 receptor (PD-1)-programmed death ligand 1 (PD-L1) immune checkpoint inhibition has been unsuccessful in clinical trials. Myeloid-derived suppressor cells (MDSCs) are known to block anti-tumor CD8+ T cell immune responses in various cancers including pancreas. This has led us to our objective that was to develop a clinically relevant in vitro organoid model to specifically target mechanisms that deplete MDSCs as a therapeutic strategy for PDAC. Method: Murine and human pancreatic ductal adenocarcinoma (PDAC) autologous organoid/immune cell co-cultures were used to test whether PDAC can be effectively treated with combinatorial therapy involving PD-1 inhibition and MDSC depletion. Results: Murine in vivo orthotopic and in vitro organoid/immune cell co-culture models demonstrated that polymorphonuclear (PMN)-MDSCs promoted tumor growth and suppressed cytotoxic T lymphocyte (CTL) proliferation, leading to diminished efficacy of checkpoint inhibition. Mouse- and human-derived organoid/immune cell co-cultures revealed that PD-L1-expressing organoids were unresponsive to nivolumab in vitro in the presence of PMN-MDSCs. Depletion of arginase 1-expressing PMN-MDSCs within these co-cultures rendered the organoids susceptible to anti-PD-1/PD-L1-induced cancer cell death. Conclusions: Here we use mouse- and human-derived autologous pancreatic cancer organoid/immune cell co-cultures to demonstrate that elevated infiltration of polymorphonuclear (PMN)-MDSCs within the PDAC tumor microenvironment inhibit T cell effector function, regardless of PD-1/PD-L1 inhibition. We present a pre-clinical model that may predict the efficacy of targeted therapies to improve the outcome of patients with this aggressive and otherwise unpredictable malignancy.


2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
Isabelle Lorthois ◽  
Daniel Asselineau ◽  
Nathalie Seyler ◽  
Roxane Pouliot

Psoriasis, a common chronic immune-mediated skin disease, is histologically characterized by a rapid keratinocyte turnover and differentiation defects. Key insights favor the idea that T cells are not the only key actors involved in the inflammatory process. Innate immune cells, more precisely neutrophils and macrophages, provide specific signals involved in the initiation and the maintenance of the pathogenesis. Current data from animal models and, to a lesser extent, three-dimensionalin vitromodels have confirmed the interest in leaning towards other immune cell types as a potential new cellular target for the treatment of the disease. Although these models do not mimic the complex phenotype nor all human features of psoriasis, their development is necessary and essential to better understand reciprocal interactions between skin cells and innate immune cells and to emphasize the crucial importance of the local lesional microenvironment. In this review, through the use ofin vivoand 3D organotypic models, we aim to shed light on the crosstalk between epithelial and immune components and to discuss the role of secreted inflammatory molecules in the development of this chronic skin disease.


2021 ◽  
Author(s):  
Nina Frey ◽  
Luigi Tortola ◽  
David Egli ◽  
Sharan Janjuha ◽  
Kim Fabiano Marquart ◽  
...  

Pancreatic ductal adenocarcinoma (PDA) is an inherently immune cell deprived tumor, characterized by desmoplastic stroma and suppressive immune cells. Here we systematically dissected PDA intrinsic mechanisms of immune evasion by in vitro and in vivo CRISPR screening, and identified Rnf31 and Vps4b as essential factors required for escaping CD8+ T cell-killing. Using murine PDA cells and human PDA organoids, we demonstrate that Rnf31 protects from TNF-mediated caspase 8 cleavage and subsequent apoptosis induction. For Vps4b we found that inactivation impairs autophagy, resulting in increased accumulation of CD8+ T cell-derived granzyme B and subsequent tumor cell lysis. Orthotopic transplantation of Rnf31- or Vps4b deficient pancreatic tumors, moreover, revealed increased CD8+ T cell infiltration and effector function, and markedly reduced tumor growth in mice. Our work uncovers vulnerabilities in PDA that might be exploited to render these tumors more susceptible to the immune system.


2019 ◽  
Author(s):  
Michael A. Badgley ◽  
Daniel Kremer ◽  
H. Carlo Maurer ◽  
Kathleen E. DelGiorno ◽  
Ho-Joon Lee ◽  
...  

AbstractPancreatic ductal adenocarcinoma (PDA) is the third-leading cause of cancer mortality in the US and is highly resistant to classical, targeted, and immune therapies. We show that human PDA cells are dependent on the provision of exogenous cystine to avert a catastrophic accumulation of lipid reactive oxygen species (ROS) that, left unchecked, leads to ferroptotic cell death, both in vitro and in vivo. Using a dual-recombinase genetically engineered model, we found that acute deletion of Slc7a11 led to tumor-selective ferroptosis, tumor stabilizations/regressions, and extended overall survival. The mechanism of ferroptosis induction in PDA cells required the concerted depletion of both glutathione and coenzyme A, highlighting a novel branch of ferroptosis-relevant metabolism. Finally, we found that cystine depletion in vivo using the pre-IND agent cyst(e)inase phenocopied Slc7a11 deletion, inducing tumor-selective ferroptosis and disease stabilizations/regressions in the well-validated KPC model of PDA.One Sentence SummaryGenetic and pharmacological targeting of cystine import induces pancreatic cancer-selective ferroptosis in vivo.


2012 ◽  
Vol 38 (12) ◽  
pp. 1121-1131
Author(s):  
Xiao-Hui WANG ◽  
Ya-Min ZHENG ◽  
Ye-Qing CUI ◽  
Shuang LIU ◽  
Hai-Chen SUN ◽  
...  

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Dehua Lu ◽  
Yanpu Wang ◽  
Ting Zhang ◽  
Feng Wang ◽  
Kui Li ◽  
...  

Abstract Background Adoptive T cell transfer-based immunotherapy yields unsatisfactory results in the treatment of solid tumors, partially owing to limited tumor infiltration and the immunosuppressive microenvironment in solid tumors. Therefore, strategies for the noninvasive tracking of adoptive T cells are critical for monitoring tumor infiltration and for guiding the development of novel combination therapies. Methods We developed a radiolabeling method for cytotoxic T lymphocytes (CTLs) that comprises metabolically labeling the cell surface glycans with azidosugars and then covalently conjugating them with 64Cu-1,4,7-triazacyclononanetriacetic acid-dibenzo-cyclooctyne (64Cu-NOTA-DBCO) using bioorthogonal chemistry. 64Cu-labeled control-CTLs and ovalbumin-specific CTLs (OVA-CTLs) were tracked using positron emission tomography (PET) in B16-OVA tumor-bearing mice. We also investigated the effects of focal adhesion kinase (FAK) inhibition on the antitumor efficacy of OVA-CTLs using a poly(lactic-co-glycolic) acid (PLGA)-encapsulated nanodrug (PLGA-FAKi). Results CTLs can be stably radiolabeled with 64Cu with a minimal effect on cell viability. PET imaging of 64Cu-OVA-CTLs enables noninvasive mapping of their in vivo behavior. Moreover, 64Cu-OVA-CTLs PET imaging revealed that PLGA-FAKi induced a significant increase in OVA-CTL infiltration into tumors, suggesting the potential for a combined therapy comprising OVA-CTLs and PLGA-FAKi. Further combination therapy studies confirmed that the PLGA-FAKi nanodrug markedly improved the antitumor effects of adoptive OVA-CTLs transfer by multiple mechanisms. Conclusion These findings demonstrated that metabolic radiolabeling followed by PET imaging can be used to sensitively profile the early-stage migration and tumor-targeting efficiency of adoptive T cells in vivo. This strategy presents opportunities for predicting the efficacy of cell-based adoptive therapies and for guiding combination regimens. Graphic Abstract


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