561 ENHANCING RADIATION-INDUCED IMMUNOGENICITY IN THE MULTIMODAL TREATMENT OF ESOPHAGEAL CANCER: IS HYPOFRACTIONATION THE ANSWER?

2020 ◽  
Vol 33 (Supplement_1) ◽  
Author(s):  
N Donlon ◽  
M Davern ◽  
A Sheppard ◽  
J Elliott ◽  
N Ravi ◽  
...  

Abstract   Esophageal adenocarcinoma (EAC) is increasing exponentially year on year in Western civilisation, linked epidemiologically to GERD and obesity. It is characterized by a highly immunosuppressive tumour microenvironment (TME) and evasion of immune surveillance. A novel treatment option is upregulating immune mediated anti-tumour response via Immune Checkpoint Blockers (ICB). Methods The effects of immune checkpoint blockers were characterised in terms of proliferation, cytolysis and cancer cell viability. The basal expression of immune checkpoints (TIGIT, PD-1, PD-L1, PD-L2) and Damage Associated Molecular Patterns (Calreticulin, HMGB1) in EAC patients was profiled ex vivo using fresh tumor, blood and lymph-node tissue (n = 10) by flow cytometry. In an in-vitro study, T-lymphocytes were isolated and treated with Nivolumab, Pembrolizumab or Atezolizumab, activated and co-cultured for 48 hours with a panel of four esophageal cancer cell lines; OE33P, OE33R, FLO-1, FLO-1LM treated with 1.8Gy and 3.6Gy of radiation (Fig 1). Cytolysis was measured using a CCK8 assay.(n = 6). Results The expression of TIGIT, TIM-3, PD-1 and its ligands (PD-L1, PD-L2) were higher (p < 0.001) in EAC patients compared to age matched healthy controls. Similarly, when mimicking conditions of the TME including nutrient deprivation and hypoxia, this results in a significant (p < 0.001) increase in DAMP and ICB expression on CD3,4 and CD8 T cells in the TME when treated with radiation. T-lymphocytes induced by checkpoint blockers plus ionising radiation directly to the tumor resulted in the best repression of tumour growth with 3.6Gy inducing the highest rate of cytolysis (p < 0.001). ICB and radiation resulted in reduced cancer cell viability and proliferation. Conclusion Fractionated radiation can enhance immunologic function. In combination with ICB, this symbiotic relationship enhances the cytotoxic potential of T lymphocytes with conventional dosing, however, with hypofractionation, this signifies true immunogenicity, and as such this provides a basis for advocating for potential combination strategies with ICB in the multimodal treatment of EAC.

2020 ◽  
Author(s):  
Jesús Pacheco-Torres ◽  
Marie-France Penet ◽  
Yelena Mironchik ◽  
Balaji Krishnamachary ◽  
Zaver M Bhujwalla

Abstract Background: Harnessing the power of the immune system by using immune checkpoint inhibitors has resulted in some of the most exciting advances in cancer treatment. The full potential of this approach has, however, not been fully realized for treating many cancers such as pancreatic and breast cancer. Cancer metabolism influences many aspects of cancer progression including immune surveillance. An expanded understanding of how cancer metabolism can directly impact immune checkpoints may allow further optimization of immunotherapy. We therefore investigated, for the first time, the relationship between the overexpression of choline kinase-α (Chk-α), an enzyme observed in most cancers, and expression of the immune checkpoint PD-L1. Methods: We used small interfering RNA to downregulate Chk-a, PD-L1 or both in two triple negative human breast cancer cell lines (MDA-MB-231 and SUM-149) and two human pancreatic ductal adenocarcinoma cell lines (Pa09C and Pa20C). The effects of the downregulation were studied at the genomic, proteomic and metabolomic levels. The findings were compared with results obtained by analysis of public data from The Cancer Genome Atlas Program.Results: We identified an inverse dependence between Chk-α and PD-L1 at the genomic, proteomic and metabolomic levels. We also found that prostaglandin-endoperoxide synthase 2 (COX-2) and transforming growth factor beta (TGF-β) play an important role in this relationship. We independently confirmed this relationship in human cancers by analyzing data from The Cancer Genome Atlas Program. Conclusions: Our data identified previously unknown roles of PD-L1 in cancer cell metabolic reprogramming, and revealed the immunosuppressive increased PD-L1 effect of Chk-α downregulation. These data suggest that PD-L1 regulation of metabolism may be mediated through Chk-α, COX-2 and TGF-β. The observations provide new insights that can be applied to the rational design of combinatorial therapies targeting immune checkpoints and cancer metabolism.


2021 ◽  
Author(s):  
Jesús Pacheco-Torres ◽  
Marie-France Penet ◽  
Yelena Mironchik ◽  
Balaji Krishnamachary ◽  
Zaver M Bhujwalla

Abstract Background: Harnessing the power of the immune system by using immune checkpoint inhibitors has resulted in some of the most exciting advances in cancer treatment. The full potential of this approach has, however, not been fully realized for treating many cancers such as pancreatic and breast cancer. Cancer metabolism influences many aspects of cancer progression including immune surveillance. An expanded understanding of how cancer metabolism can directly impact immune checkpoints may allow further optimization of immunotherapy. We therefore investigated, for the first time, the relationship between the overexpression of choline kinase-α (Chk-α), an enzyme observed in most cancers, and expression of the immune checkpoint PD-L1. Methods: We used small interfering RNA to downregulate Chk-a, PD-L1 or both in two triple negative human breast cancer cell lines (MDA-MB-231 and SUM-149) and two human pancreatic ductal adenocarcinoma cell lines (Pa09C and Pa20C). The effects of the downregulation were studied at the genomic, proteomic and metabolomic levels. The findings were compared with results obtained by analysis of public data from The Cancer Genome Atlas Program.Results: We identified an inverse dependence between Chk-α and PD-L1 at the genomic, proteomic and metabolomic levels. We also found that prostaglandin-endoperoxide synthase 2 (COX-2) and transforming growth factor beta (TGF-β) play an important role in this relationship. We independently confirmed this relationship in human cancers by analyzing data from The Cancer Genome Atlas Program. Conclusions: Our data identified previously unknown roles of PD-L1 in cancer cell metabolic reprogramming, and revealed the immunosuppressive increased PD-L1 effect of Chk-α downregulation. These data suggest that PD-L1 regulation of metabolism may be mediated through Chk-α, COX-2 and TGF-β. The observations provide new insights that can be applied to the rational design of combinatorial therapies targeting immune checkpoints and cancer metabolism.


2020 ◽  
Vol 17 (1) ◽  
Author(s):  
Rosanne D. Reitsema ◽  
Rebeca Hid Cadena ◽  
Sander H. Nijhof ◽  
Wayel H. Abdulahad ◽  
Minke G. Huitema ◽  
...  

Abstract Background Immune checkpoints are crucial molecules in maintaining a proper immune balance. Even though age and sex are known to have effects on the immune system, the interplay between age, sex and immune checkpoint expression by T cells is not known. The aim of this study was to determine whether age and sex affect immune checkpoint expression by T cells and if age and sex affect the kinetics of immune checkpoint expression following ex vivo stimulation. In this study, whole blood samples of 20 healthy young adults (YA, 9 males and 11 females) and 20 healthy older adults (OA, 9 males and 11 females) were stained for lymphocyte lineage markers and immune checkpoints and frequencies of CD28+, PD-1+, VISTA+ and CD40L+ T cells were determined. Immune checkpoint expression kinetics were studied following ex vivo anti-CD3/anti-CD28 stimulation of T cells from young and older healthy adults. Results We report an age-associated increase of CD40L + CD4+ and CD40L + CD8+ T-cell frequencies, whereas CD40+ B-cell frequencies were decreased in older adults, suggesting modulation of the CD40L-CD40 interaction with age. Immune checkpoint expression kinetics revealed differences in magnitude between CD4+ and CD8+ T cells independent of age and sex. Further analysis of CD4+ T-cell subsets revealed an age-associated decrease of especially PD-1 + CD4+ memory T cells which tracked with the female sex. Conclusion Collectively, our results demonstrate that both age and sex modulate expression of immune checkpoints by human T cells. These findings may have implications for optimising vaccination and immune checkpoint immunotherapy and move the field towards precision medicine in the management of older patient groups.


2017 ◽  
Vol 35 (15_suppl) ◽  
pp. 4060-4060
Author(s):  
Ronan Joseph Kelly ◽  
Ali Hussainy Zaidi ◽  
Matthew A Smith ◽  
Ashten N Omstead ◽  
Juliann E Kosovec ◽  
...  

4060 Background: PD-1 inhibitors in metastatic gastroesophageal cancer have demonstrated response rates of approximately 25%. Unfortunately, the majority of patients do not respond. Therefore, a rationale strategy of combining immunotherapeutic agents with CRT in earlier stage esophageal cancer may prevent metastatic disease in a greater proportion of patients. This study assessed the impact of CRT on the immune microenvironment and the expression patterns of multiple immune checkpoints to optimally design neoadjuvant clinical trials. Methods: To determine the effects of CRT on resected esophageal adenocarcinomas (EAC), we examined the immune microenvironment pre and post CRT using IHC, LCM followed by qRT-PCR, and functional analysis of tumor-infiltrating lymphocytes. Additionally, to assess the duration and dependency of radiation-induced PD-L1 sensitization, esophagojejunostomy were performed on rats to induce gastroduodenoesophageal reflux and EAC formation. First, tumor bearing animals were dosed with single fraction 13 Gy or 16 Gy radiation to determine safety, dose correlation, and PD-L1 sensitization using qRT-PCR post-radiation. Next, longitudinal PD-L1 expression levels within individual tumor bearing animals were determined using serial endoscopic biopsies at baseline, 1, 5 and 9 weeks post 16 Gy radiation. Results: The majority of cancers displayed enhanced interferon γ and activated CD8+ T lymphocytes at the tumor stroma interface. These tumors also demonstrated enhanced upregulation of PD-L1 and multiple other immune checkpoints including – TIM3, GITR, IDO1, LAG3, CD137, OX40 and KIR. The animal model results indicated PD-L1 upregulation is dose dependent and transiently elevated post radiation exposure. Conclusions: Collectively, these findings provide insights into the evolving immune landscape after CRT and have significant implications for future neoadjuvant trial designs that will combine radiotherapy with immune checkpoint inhibitors. Currently, we are conducting a neoadjuvant trial assessing Nivolumab or Nivolumab/Ipilimumab in combination with CRT in stage II/III operable esophageal cancer.


2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Jesus Pacheco-Torres ◽  
Marie-France Penet ◽  
Yelena Mironchik ◽  
Balaji Krishnamachary ◽  
Zaver M. Bhujwalla

Abstract Background Harnessing the power of the immune system by using immune checkpoint inhibitors has resulted in some of the most exciting advances in cancer treatment. The full potential of this approach has, however, not been fully realized for treating many cancers such as pancreatic and breast cancer. Cancer metabolism influences many aspects of cancer progression including immune surveillance. An expanded understanding of how cancer metabolism can directly impact immune checkpoints may allow further optimization of immunotherapy. We therefore investigated, for the first time, the relationship between the overexpression of choline kinase-α (Chk-α), an enzyme observed in most cancers, and the expression of the immune checkpoint PD-L1. Methods We used small interfering RNA to downregulate Chk-α, PD-L1, or both in two triple-negative human breast cancer cell lines (MDA-MB-231 and SUM-149) and two human pancreatic ductal adenocarcinoma cell lines (Pa09C and Pa20C). The effects of the downregulation were studied at the genomic, proteomic, and metabolomic levels. The findings were compared with the results obtained by the analysis of public data from The Cancer Genome Atlas Program. Results We identified an inverse dependence between Chk-α and PD-L1 at the genomic, proteomic, and metabolomic levels. We also found that prostaglandin-endoperoxide synthase 2 (COX-2) and transforming growth factor beta (TGF-β) play an important role in this relationship. We independently confirmed this relationship in human cancers by analyzing data from The Cancer Genome Atlas Program. Conclusions Our data identified previously unknown roles of PD-L1 in cancer cell metabolic reprogramming, and revealed the immunosuppressive increased PD-L1 effect of Chk-α downregulation. These data suggest that PD-L1 regulation of metabolism may be mediated through Chk-α, COX-2, and TGF-β. The observations provide new insights that can be applied to the rational design of combinatorial therapies targeting immune checkpoints and cancer metabolism.


2021 ◽  
Author(s):  
Shirin Lak ◽  
Valérie Janelle ◽  
Anissa Djedid ◽  
Gabrielle Boudreau ◽  
Ann Brasey ◽  
...  

AbstractBackgroundThe stimulation and expansion of antigen-specific T cells ex vivo enables the targeting of a multitude of cancer antigens. However, clinical scale T-cell expansion from rare precursors requires repeated stimulations ex vivo leading to T-cell terminal effector differentiation and exhaustion that adversely impact therapeutic potential. We leveraged immune checkpoint blockade relevant to antigen-specific CD8+ human T cells to improve the expansion and function of T cells targeting clinically relevant antigens.MethodsA clinically-compliant protocol relying on peptide-pulsed monocyte-derived dendritic cells and cytokines was used to expand antigen-specific CD8+ targeting the oncogenic Epstein-Barr virus (EBV) and the tumor associated antigen (TAA) Wilms Tumor 1 (WT1) protein. The effects of antibody-mediated blockade of immune checkpoints applied to the cultures (T-cell expansion, phenotypes and function) were assessed at various time points. Genomic studies including single cell RNA (scRNA) sequencing and T-cell receptor sequencing were performed on EBV-specific T cells to inform about the impact of immune checkpoint blockade on the clonal distribution and gene expression of the expanded T cells.ResultsSeveral immune checkpoints were expressed early by ex vivo expanded antigen-specific CD8+ T cells, including PD-1 and TIM-3 with co-expression matching evidence of T-cell dysfunction as the cultures progressed. The introduction of anti-PD-L1 (expressed by the dendritic cells) and anti-TIM-3 antibodies in combination (but not individually) to the culture led to markedly improved antigen-specific T-cell expansion based on cell counts, fluorescent multimer staining and functional tests. This was not associated with evidence of T-cell dysfunction when compared to T cells expanded without immune checkpoint blockade. Genomics studies largely confirmed these results, showing that double blockade does not impart specific transcriptional programs or patterns on TCR repertoires. However, our data indicate that combined blockade may nonetheless alter gene expression in a minority of clonotypes and have donor-specific impacts.ConclusionsThe manufacturing of antigen-specific CD8+ T cells can be improved in terms of yield and functionality using blockade of TIM-3 and the PD-L1/PD-1 axis in combination. Overcoming the deleterious effects of multiple antigenic stimulations through PD-L1/TIM-3 blockade is a readily applicable approach for several adoptive-immunotherapy strategies.


2020 ◽  
Vol 27 (15) ◽  
pp. 2402-2448 ◽  
Author(s):  
Paolo D’Arrigo ◽  
Martina Tufano ◽  
Anna Rea ◽  
Vincenza Vigorito ◽  
Nunzia Novizio ◽  
...  

The immune system actively counteracts the tumorigenesis process; a breakout of the immune system function, or its ability to recognize transformed cells, can favor cancer development. Cancer becomes able to escape from immune system control by using multiple mechanisms, which are only in part known at a cellular and molecular level. Among these mechanisms, in the last decade, the role played by the so-called “inhibitory immune checkpoints” is emerging as pivotal in preventing the tumor attack by the immune system. Physiologically, the inhibitory immune checkpoints work to maintain the self-tolerance and attenuate the tissue injury caused by pathogenic infections. Cancer cell exploits such immune-inhibitory molecules to contrast the immune intervention and induce tumor tolerance. Molecular agents that target these checkpoints represent the new frontier for cancer treatment. Despite the heterogeneity and multiplicity of molecular alterations among the tumors, the immune checkpoint targeted therapy has been shown to be helpful in selected and even histologically different types of cancer, and are currently being adopted against an increasing variety of tumors. The most frequently used is the moAb-based immunotherapy that targets the Programmed Cell Death 1 protein (PD-1), the PD-1 Ligand (PD-L1) or the cytotoxic T lymphocyte antigen-4 (CTLA4). However, new therapeutic approaches are currently in development, along with the discovery of new immune checkpoints exploited by the cancer cell. This article aims to review the inhibitory checkpoints, which are known up to now, along with the mechanisms of cancer immunoediting. An outline of the immune checkpoint targeting approaches, also including combined immunotherapies and the existing trials, is also provided. Notwithstanding the great efforts devoted by researchers in the field of biomarkers of response, to date, no validated FDA-approved immunological biomarkers exist for cancer patients. We highlight relevant studies on predictive biomarkers and attempt to discuss the challenges in this field, due to the complex and largely unknown dynamic mechanisms that drive the tumor immune tolerance.


2021 ◽  
Vol 24 (1) ◽  
Author(s):  
Jun Peng ◽  
Ke Ma ◽  
Hao Rong ◽  
Bo Xiao ◽  
Jiang Zhu ◽  
...  

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