scholarly journals 322 Melanoma-intrinsic hypoxia-inducible factor-1α results in diminished T cell accumulation within the tumor microenvironment

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A347-A347
Author(s):  
Emily Higgs ◽  
Thomas Gajewski ◽  
Jonathan Trujillo

BackgroundThe hypoxia-inducible factor (HIF) system, consisting of the transcription factors HIF-1α and HIF-2α, mediates cellular adaptation to hypoxia, and can promote cancer progression, invasion, and metastasis. HIF pathway activation in the tumor microenvironment has been implicated in cancer immune evasion; however, a direct causal role for tumor cell-intrinsic HIF-1α and HIF-2α activation in mediating T cell exclusion and cancer cell resistance to immune checkpoint inhibitor therapy has not been demonstrated.MethodsWe performed gene expression analysis of melanoma tumors in the Cancer Genome Atlas (TCGA) data set to determine whether increased HIF-1α pathway activation correlated with reduced T cell-based inflammation. The magnitude of HIF-1α pathway activation across melanoma samples was determined by applying a quantitative scoring system on the expression of a melanocyte-specific hypoxia-induced, HIF-1α-target gene signature consisting of 81 genes. The Pearson correlation test was used to compare the HIF-1α activation score and our 160-gene T-cell-inflamed gene signature. To determine the impact of cancer cell-intrinsic HIF-1α or HIF-2α activation on the endogenous anti-tumor T cell response, we developed an inducible autochthonous mouse melanoma model driven by BRAFV600E expression and PTEN-deletion, with or without inducible expression of either a stabilized variant of HIF-1α or HIF-2α. These murine tumor models are being used to determine the impact of cancer cell-intrinsic HIF-1α or HIF-2α activation on tumor sensitivity to anti-PD-1/PD-L1 and anti-CTLA-4 treatment.ResultsGene expression analysis of human melanomas in the TCGA demonstrated a statistically significant inverse correlation between the HIF-1α activation score and T cell-inflammation score. Braf/PTEN murine melanomas with and without stabilized HIF-1α expression developed with comparable tumor onset and growth kinetics. Multiparameter immunofluorescence staining of melanoma tissue revealed a significant decrease in tumor-infiltrating T cells within Braf/PTEN melanoma tumors expressing stabilized HIF-1α compared to control Braf/PTEN melanomas.ConclusionsOur data demonstrate that tumor-cell intrinsic HIF-1α activation leads to diminished T cell accumulation within the tumor microenvironment, which has implications for cancer immunotherapy. The mechanism of this effect is being elucidated. These novel murine models will help elucidate the roles of cancer cell-intrinsic HIF-1α and HIF-2α activation in modulating the anti-tumor T cell response, providing mechanistic insight that will inform the evaluation of novel selective HIF inhibitors, which are showing promising anti-tumor activity in clinical trials in patients with advanced solid tumors.

2021 ◽  
Vol 10 (1) ◽  
pp. 1956143
Author(s):  
Anna Sosnowska ◽  
Justyna Chlebowska-Tuz ◽  
Pawel Matryba ◽  
Zofia Pilch ◽  
Alan Greig ◽  
...  

Cancers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 3286
Author(s):  
Dariusz Lachowski ◽  
Carlos Matellan ◽  
Ernesto Cortes ◽  
Alberto Saiani ◽  
Aline F. Miller ◽  
...  

The tumor microenvironment plays a critical role in modulating cancer cell migration, metabolism, and malignancy, thus, highlighting the need to develop in vitro culture systems that can recapitulate its abnormal properties. While a variety of stiffness-tunable biomaterials, reviewed here, have been developed to mimic the rigidity of the tumor extracellular matrix, culture systems that can recapitulate the broader extracellular context of the tumor microenvironment (including pH and temperature) remain comparably unexplored, partially due to the difficulty in independently tuning these parameters. Here, we investigate a self-assembled polypeptide network hydrogel as a cell culture platform and demonstrate that the culture parameters, including the substrate stiffness, extracellular pH and temperature, can be independently controlled. We then use this biomaterial as a cell culture substrate to assess the effect of stiffness, pH and temperature on Suit2 cells, a pancreatic cancer cell line, and demonstrate that these microenvironmental factors can regulate two critical transcription factors in cancer: yes-associated protein 1 (YAP) and hypoxia inducible factor (HIF-1A).


2016 ◽  
Vol 21 (8) ◽  
pp. 769-785 ◽  
Author(s):  
Emma S. Hickman ◽  
Martine E. Lomax ◽  
Bent K. Jakobsen

Evidence of adaptive immune responses in the prevention of cancer has been accumulating for decades. Spontaneous T-cell responses occur in multiple indications, bringing the study of de novo expressed cancer antigens to the fore and highlighting their potential as targets for cancer immunotherapy. Circumventing the immune-suppressive mechanisms that maintain tumor tolerance and driving an antitumor cytotoxic T-cell response in cancer patients may eradicate the tumor or block disease progression. Multiple strategies are being pursued to harness the cytotoxic potential of T cells clinically. Highly promising results are now emerging. The focus of this review is the target discovery process for cancer immune therapeutics based on affinity-matured T-cell receptors (TCRs). Target cancer antigens in the context of adoptive cell transfer technologies and soluble biologic agents are discussed. To appreciate the impact of TCR-based technology and understand the TCR discovery process, it is necessary to understand key differences between TCR-based therapy and other immunotherapy approaches. The review first summarizes key advances in the cancer immunotherapy field and then discusses the opportunities that TCR technology provides. The nature and breadth of molecular targets that are tractable to this approach are discussed, together with the challenges associated with finding them.


2021 ◽  
Vol 39 (15_suppl) ◽  
pp. e14565-e14565
Author(s):  
Amit Adhikari ◽  
Juliete Macauley ◽  
Yoshimi Johnson ◽  
Mike Connolly ◽  
Tim Coleman ◽  
...  

e14565 Background: Glioblastoma (GBM) is an aggressive form of brain cancer with a median survival of 15 months which has remained unchanged despite technological advances in the standard of care. GBM cells specifically express human cytomegalovirus (HCMV) proteins providing a unique opportunity for targeted therapy. Methods: We utilized our UNITE (UNiversal Intracellular Targeted Expression) platform to develop a multi-antigen DNA vaccine (ITI-1001) that codes for the HCMV proteins- pp65, gB and IE-1. The UNITE platform involves lysosomal targeting technology, fusing lysosome-associated protein 1 (LAMP1) with target antigens resulting in increased antigen presentation by MHC-I and II. ELISpot, flow cytometry and ELISA techniques were used to evaluate the vaccine immunogenicity and a syngeneic, orthotopic GBM mouse model that expresses HCMV proteins was used for efficacy studies. The tumor microenvironment studies were done using flow cytometry and MSD assay. Results: ITI-1001 vaccination showed a robust antigen-specific CD4 and CD8 T cell response in addition to a strong humoral response. Using GBM mouse model, therapeutic treatment of ITI-1001 vaccine resulted in ̃56% survival with subsequent long-term immunity. Investigating the tumor microenvironment showed significant CD4 T cell infiltration as well as enhanced Th1 and CD8 T cell activation. Regulatory T cells were also upregulated upon ITI-1001 vaccination and would be an attractive target to further improve this therapy. In addition, tumor burden negatively correlated with number of activated CD4 T cells (CD4 IFNγ+) reiterating the importance of CD4 activation in ITI-1001 efficacy and potentially identifying treatment responders and non-responders. Further characterization of these two groups showed high infiltration of CD3+, CD4+ and CD8+ T cells in responders compared with non- responders along with higher CD8 T cell activation. Conclusions: Thus, we show that vaccination with HCMV antigens using the ITI-1001-UNITE platform generates strong cellular and humoral immune responses, triggering significant anti-tumor activity that leads to enhanced survival in mice with GBM.


2020 ◽  
Vol 8 (Suppl 2) ◽  
pp. A21.1-A21
Author(s):  
E Staib ◽  
K Leuchte ◽  
M Thelen ◽  
P Gödel ◽  
A Lechner ◽  
...  

BackgroundThermal ablative therapies, such as microwave ablation (MWA) or radiofrequency ablation (RFA), are standard treatments for HCC. In addition to the local tumor destruction, abscopal effects (a reduction of a tumor mass in areas that were not included in the thermal ablation) could be observed. These systemic effects may be mediated by anti-tumor immune response, which has been described for RFA. MWA is rapidly replacing RFA, but systemic immunostimulatory effects of MWA treatment have been poorly studied.Materials and MethodsPatients receiving MWA for localized HCC were included in this study. Effects of MWA on peripheral blood mononuclear cells (PBMC) of HCC patients treated with MWA were analyzed by multicolor flow cytometry. Tumor-specific immune responses against 7 shared tumor antigens were analyzed using peptide pools in 3-color Fluorospot assays (Interferon-y/Interleukin-5/Interleukin-10). The impact of type, density and localization of tumor-infiltrating lymphocytes was assessed by immunohistochemistry (IHC) of CD3, CD4, CD8, FoxP3, CD38 and CD20 and digital image analyses (Immunoscore) of tumor specimens in an additional cohort of patients who received combined surgical resection and thermal ablation.ResultsWhile comprehensive flow cytometric analyses in sequential samples (day 0, 7 and 90) of a prospective patient cohort (n=23) demonstrated only moderate effects of MWA on circulating immune cell subsets, Fluorospot analyses revealed de novo or enhanced tumor-specific immune responses in 30% of these patients. This anti-tumor immune response was related to tumor control. Interferon-y and Interleukin-5 T cell responses against cancer testis antigens were more frequent in patients with a long-time remission (>12 months) after MWA (7/16) compared to patients suffering from an early relapse (0/13 patients). Presence of tumor-specific T cell response (Interferon-y and/or Interleukin-5) was associated to longer progression-free survival (15.0 vs. 10.0 months). Immunohistochemical analyses of resected tumor samples revealed that a high T cell infiltration in a second tumor lesion at the time of thermal ablation was associated with superior disease-free survival (37.4 vs. 13.1 months).ConclusionsOur data demonstrates remarkable immune-related effects of MWA in HCC patients. This study and provides additional evidence for a combination of thermal ablation and immunotherapy in this challenging disease.Funding‘Koeln Fortune’ and ‘CAP-CMMC’ local research grant (to P.G. and H.A.S.) supported our research.Disclosure InformationE. Staib: None. K. Leuchte: None. M. Thelen: None. P. Gödel: None. A. Lechner: None. P. Zentis: None. M. Garcia-Marquez: None. D. Waldschmidt: None. R.R. Datta: None. R. Wahba: None. C. Wybranski: None. T. Zander: None. A. Quaas: None. U. Drebber: None. D.L. Stippel: None. C. Bruns: None. K. Wennhold: None. M. von Bergwelt-Baildon: None. H.A. Schlösser: None.


2020 ◽  
Vol 6 (20) ◽  
pp. eaaz9240 ◽  
Author(s):  
Zhaoting Li ◽  
Yixin Wang ◽  
Yuexin Shen ◽  
Chenggen Qian ◽  
David Oupicky ◽  
...  

Anti–programmed cell death 1 ligand 1 (PD-L1) therapy is extraordinarily effective in select patients with cancer. However, insufficient lymphocytic infiltration, weak T cell–induced inflammation, and immunosuppressive cell accumulation in the tumor microenvironment (TME) may greatly diminish the efficacy. Here, we report development of the FX@HP nanocomplex composed of fluorinated polymerized CXCR4 antagonism (FX) and paclitaxel-loaded human serum albumin (HP) for pulmonary delivery of anti–PD-L1 small interfering RNA (siPD-L1) to treat orthotopic lung tumors. FX@HP induced T cell infiltration, increased expression of calreticulin on tumor cells, and reduced the myeloid-derived suppressor cells/regulatory T cells in the TME, thereby acting synergistically with siPD-L1 for effective immunotherapy. Our work suggests that the CXCR4-inhibiting nanocomplex decreases tumor fibrosis, facilitates T cell infiltration and relieves immunosuppression to modulate the immune process to improve the objective response rate of anti–PD-L1 immunotherapy.


Author(s):  
Mary Poupot ◽  
Frédéric Boissard ◽  
Delphine Betous ◽  
Laure Bardouillet ◽  
Séverine Fruchon ◽  
...  

AbstractPhosphoantigens (PAgs) activate Vγ9Vδ2 T lymphocytes, inducing their potent and rapid response in vitro and in vivo. However, humans and nonhuman primates that receive repeated injections of PAgs progressively lose their Vγ9Vδ2 T cell response to them. To elucidate the molecular mechanisms of this in vivo desensitization, we analyzed the transcriptome of circulating Vγ9Vδ2 T cells from macaques injected with PAg. We showed that three PAg injections induced the activation of the PPARα pathway in Vγ9Vδ2 T cells. Thus, we analyzed the in vitro response of Vγ9Vδ2 T cells stimulated with a PPARα agonist. We demonstrated that in vitro PPARα pathway activation led to the inhibition of the BrHPP-induced activation and proliferation of human Vγ9Vδ2 T cells. Since the PPARα pathway is involved in the antigen-selective desensitization of human Vγ9Vδ2 T cells, the use of PPARα inhibitors could enhance cancer immunotherapy based on Vγ9Vδ2 T cells.


2002 ◽  
Vol 70 (1) ◽  
pp. 153-162 ◽  
Author(s):  
Amy R. Tvinnereim ◽  
Sara E. Hamilton ◽  
John T. Harty

ABSTRACT Understanding how existing antivector immunity impacts live vaccine delivery systems is critical when the same vector system may be used to deliver different antigens. We addressed the impact of antivector immunity, elicited by immunization with attenuated actA-deficient Listeria monocytogenes, on the CD8+-T-cell response to a well-characterized lymphocytic choriomeningitis virus epitope, NP118-126, delivered by infection with recombinant L. monocytogenes. Challenges of immune mice with actA-deficient and with wild-type recombinant L. monocytogenes generated similar numbers of CD8+ T cells specific for the NP118-126 epitope. High-dose immunization with actA-deficient L. monocytogenes resulted in substantial numbers of CD8+ T cells specific for the L. monocytogenes LLO91-99 epitope in the effector and memory stages of the T-cell response. Challenge of these immune mice with recombinant L. monocytogenes resulted in rapid control of the infection and decreased CD8+-T-cell responses against both the secreted and nonsecreted form of the recombinant antigen compared to the response of naïve mice. In contrast, mice immunized with a low dose of actA-deficient L. monocytogenes had ∼10-fold fewer effector and memory T cells specific for LLO91-99 and a substantially higher CD8+-T-cell response against the recombinant antigen after challenge with recombinant L. monocytogenes. Although mice immunized with low-dose actA-deficient L. monocytogenes had a substantial recall response to LLO91-99, which reached the same levels by 5 to 7 days postchallenge as that in high-dose-immunized mice, they exhibited decreased ability to control L. monocytogenes replication. Thus, the level of antivector immunity impacts the control of infection and efficiency of priming responses against new antigens introduced with the same vector.


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