PD-1 Expression by Lymph Node and Intratumoral Regulatory T Cells Is Associated with Lymph Node Metastasis in Pancreatic Cancer

The clinical significance of PD-1 expression in patients with bladder cancer without lymph node metastasis: a comparative study with drained lymph nodes and tumor tissues

OBJECTIVE

In light of the increasing importance of immunotherapy in bladder cancer treatment, this study is aim to investigate the expression and clinical significance of programmed cell surface death-1 (PD-1) in bladder cancer patients without lymph node metastasis, and to compare and analyze the difference of PD-1 in draining lymph nodes and tumor tissues.

METHODS

The expression of PD-1 on T cells and the proportion of positive PD-1 + T cells of IFN-γ and CD105a were detected by flow cytometry, and the correlation between PD-1 expression and clinical parameters was analyzed.

RESULTS

The percentage of PD-1 positive cells in drainage lymph nodes was higher than that in tumor tissues (P < 0.001). PD-1 positive cells accounted for the highest proportion in CD3 + T cells. The proportion of IFN-γ-positive PD-1 + T cells in draining lymph nodes was significantly higher than that in tumor tissues (P < 0.001), while there was no significant difference in CD105a positive PD-1 + T cells between tumor tissues and draining lymph nodes. Pathological grade, tumor size and stage were positively correlated with PD-1 expression level in the lymph nodes.

CONCLUSION

The high expression of PD-1 in patients with bladder cancer without lymph node metastasis, especially in draining lymph nodes, suggests that PD-1 may play a key role in the regulation of tumor immune microenvironment. The correlation between PD-1 and clinical parameters indicates its potential prognostic value. These findings provide important clinical implications for PD-1 targeted therapy, but further prospective studies are needed to determine the application value of PD-1 in therapeutic strategies.

Targeted Therapy for Highly Desmoplastic and Immunosuppressive Tumor Microenvironment of Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy with a very poor prognosis. Despite advancements in treatment strategies, PDAC remains recalcitrant to therapies because patients are often diagnosed at an advanced stage. The advanced stage of PDAC is characterized by metastasis, which typically renders it unresectable by surgery or untreatable by chemotherapy. The tumor microenvironment (TME) of PDAC comprises highly proliferative myofibroblast-like cells and hosts the intense deposition of a extracellular matrix component that forms dense fibrous connective tissue, a process called the desmoplastic reaction. In desmoplastic TMEs, the incessant aberration of signaling pathways contributes to immunosuppression by suppressing antitumor immunity. This feature offers a protective barrier that impedes the targeted delivery of drugs. In addition, the efficacy of immunotherapy is compromised because of the immune cold TME of PDAC. Targeted therapy approaches towards stromal and immunosuppressive TMEs are challenging. In this review, we discuss cellular and non-cellular TME components that contain actionable targets for drug development. We also highlight findings from preclinical studies and provide updates about the efficacies of new investigational drugs in clinical trials.

T Cell Exhaustion and Activation Markers in Pancreatic Cancer: A Systematic Review

BACKGROUND

T cell exhaustion and activation markers are helpful in determining the therapies and predicting the overall survival in pancreatic cancer (PC) patients.

PURPOSE

In this systematic review, we have addressed two questions, how do these markers differ in their expression levels in PC patients and healthy individual and correlating the expression level of these markers with the cancer stage.

METHODS

The systematic review was registered with Prospective Register of Systematic Reviews (PROSPERO) with registration number "CRD42022246780." All the included articles were obtained from three databases, PubMed, MEDLINE, and Cochrane, published from January 2010 to 26th May 2022. Two independent reviewers followed the PRISM protocol and reviewed and extracted data from the included articles.

RESULTS

PD-1 and CTLA-4 were the most studied markers in this field. A clear elevation in the expression of PD-1, CTLA-4, TIM-3, LAG-3, and TIGIT was found in most of the studies. CD69, CD25, and HLA-DR expression was found to be upregulated after chemotherapy and immunotherapy. CD25 was the only marker analyzed against cancer progression, in a single study. No study compared the expression of exhaustion and activation markers (except CD69) with the cancer progression of the tumor stage.

CONCLUSION

Since the exhaustion markers are upregulated in patients, single or multiple markers can be targeted in immunotherapies. Knowledge of the dynamics of these markers at various cancer stages will help in determining the right immunotherapy for pancreatic cancer patients. Stage-wise comparison could also be made possible by developing in vitro models.

The Relationship between Cancer Stage, Selected Immunological Parameters, Epstein-Barr Virus Infection, and Total Serum Content of Iron, Zinc, and Copper in Patients with Laryngeal Cancer

(1) Background: the purpose of the study was to assess the relationship between cancer stage, selected immunological parameters, Epstein-Barr virus (EBV) infection, and total serum content of iron, zinc, and copper in patients with laryngeal cancer (LC). (2) Methods: serum Fe, Zn, and Cu were measured in 40 LC patients and 20 controls. Immunophenotyping of peripheral blood lymphocytes was performed by flow cytometry using fluorescent antibodies against CD3, CD4, CD8, CD19, CD25, CD69, and PD-1. Tumor and lymph node lymphocytes were analyzed by flow cytometry. EBV DNA was quantified by real-time PCR, targeting the EBNA-1 gene. Associations between serum elements, immune markers, and cancer grade/stage were evaluated using ANOVA and appropriate nonparametric tests. (3) Results: levels of Fe, Cu, and Zn were lower, while Cu/Zn was statistically higher, in patients with LC than in the control group. Correlation analysis showed a statistically significant association between the levels of these elements and parameters of the TNM (Tumor, Node, Metastasis) staging system, immunophenotype, and the amount of EBV genetic material in patients with LC who survived for more than 5 years. (4) Conclusion: the results suggest that the total serum levels of the determined micronutrients may significantly affect the immunopathogenesis and progression of LC.

Increased levels of PD1 and glycolysis in CD4+ T cells are positively associated with lymph node metastasis in OSCC

BACKGROUND

Cervical lymph node metastasis is one of the poorest prognostic factors in oral squamous cell carcinoma (OSCC). Activated immune cells generally have metabolic abnormalities in the tumour microenvironment. However, it is unknown whether abnormal glycolysis in T cells could facilitate metastatic lymph nodes in OSCC patients. The aim of this study was to investigate the effects of immune checkpoints in metastatic lymph nodes and determine the correlation between glycolysis and immune checkpoint expression in CD4⁺ T cells.

METHODS

Flow cytometry and immunofluorescence staining were used to analyse the differences in CD4⁺ PD1⁺ T cells between metastatic lymph nodes (LN⁺) and negative lymph nodes (LN^-). RT‒PCR was performed to detail the expression of immune checkpoints and glycolysis-related enzymes in LN⁺ and LN^-.

RESULTS

The frequency of CD4⁺ T cells decreased in LN⁺ patients (p = 0.0019). The PD1 expression of LN⁺ increased markedly compared to that of LN^- (p = 0.0205). Similarly, the PD1 of CD4⁺ T cells in LN⁺ increased significantly compared to that of LN^-. Additionally, glycolysis-related enzyme levels in CD4⁺ T cells from LN⁺ patients were dramatically higher than those in LN^- patients. PD1 and Hk2 expression in CD4⁺ T cells was also increased in LN⁺ OSCC patients with prior surgical treatment compared to those without.

CONCLUSIONS

These findings suggest that lymph node metastasis and recurrence in OSCC are associated with increases in PD1 and glycolysis in CD4⁺ T cells; this response may serve as a potential regulator of OSCC progression.

VISTA Ligation Reduces Antitumor T-Cell Activity in Pancreatic Cancer

Immunotherapy has shown promising results in multiple solid tumors and hematological malignancies. However, pancreatic ductal adenocarcinoma (PDAC) has been largely refractory to current clinical immunotherapies. The V-domain Ig suppressor of T-cell activation (VISTA) inhibits T-cell effector function and maintains peripheral tolerance. Here, we determine VISTA expression in nontumorous pancreatic (n = 5) and PDAC tissue using immunohistochemistry (n = 76) and multiplex immunofluorescence staining (n = 67). Additionally, VISTA expression on tumor-infiltrating immune cells and matched blood samples (n = 13) was measured with multicolor flow cytometry. Further, the effect of recombinant VISTA on T-cell activation was investigated in vitro, and VISTA blockade was tested in an orthotopic PDAC mouse model in vivo. PDAC showed significantly higher VISTA expression compared to that of a nontumorous pancreas. Patients with a high density of VISTA-expressing tumor cells had reduced overall survival. The VISTA expression of CD4⁺ and CD8⁺ T cells was increased after stimulation and particularly after a coculture with tumor cells. We detected a higher level of proinflammatory cytokine (TNFα and IFNγ) expression by CD4⁺ and CD8⁺ T cells, which was reversed with the addition of recombinant VISTA. A VISTA blockade reduced tumor weights in vivo. The VISTA expression of tumor cells has clinical relevance, and its blockade may be a promising immunotherapeutic strategy for PDAC.

Targeting tumor immunosuppressive microenvironment for pancreatic cancer immunotherapy: Current research and future perspective

Pancreatic cancer is one of the most malignant tumors with increased incidence rate. The effect of surgery combined with chemoradiotherapy on survival of patients is unsatisfactory. New treatment strategy such as immunotherapy need to be investigated. The accumulation of desmoplastic stroma, infiltration of immunosuppressive cells including myeloid derived suppressor cells (MDSCs), tumor associated macrophages (TAMs), cancer‐associated fibroblasts (CAFs), and regulatory T cells (Tregs), as well as tumor associated cytokine such as TGF-β, IL-10, IL-35, CCL5 and CXCL12 construct an immunosuppressive microenvironment of pancreatic cancer, which presents challenges for immunotherapy. In this review article, we explore the roles and mechanism of immunosuppressive cells and lymphocytes in establishing an immunosuppressive tumor microenvironment in pancreatic cancer. In addition, immunotherapy strategies for pancreatic cancer based on tumor microenvironment including immune checkpoint inhibitors, targeting extracellular matrix (ECM), interfering with stromal cells or cytokines in TME, cancer vaccines and extracellular vesicles (EVs) are also discussed. It is necessary to identify an approach of immunotherapy in combination with other modalities to produce a synergistic effect with increased response rates in pancreatic cancer therapy.

Neoadjuvant chemotherapy drives intratumoral T cells toward a proinflammatory profile in pancreatic cancer

BACKGROUNDPancreatic ductal adenocarcinoma (PDAC) has a dismal prognosis. At diagnosis, only 20% of patients with PDAC are eligible for primary resection. Neoadjuvant chemotherapy can enable surgical resection in 30%-40% of patients with locally advanced and borderline resectable PDAC. The effects of neoadjuvant chemotherapy on the cytokine production of tumor-infiltrating T cells are unknown in PDAC.METHODSWe performed multiplex immunofluorescence to investigate T cell infiltration in 91 patients with PDAC. Using flow cytometry, we analyzed tumor and matched blood samples from 71 patients with PDAC and determined the frequencies of T cell subsets and their cytokine profiles. Both cohorts included patients who underwent primary resection and patients who received neoadjuvant chemotherapy followed by surgical resection.RESULTSIn human PDAC, T cells were particularly enriched within the tumor stroma. Neoadjuvant chemotherapy markedly enhanced T cell density within the ductal area of the tumor. Whereas infiltration of cytotoxic CD8+ T cells was unaffected by neoadjuvant chemotherapy, the frequency of conventional CD4+ T cells was increased, and the proportion of Tregs was reduced in the pancreatic tumor microenvironment after neoadjuvant treatment. Moreover, neoadjuvant chemotherapy increased the production of proinflammatory cytokines by tumor-infiltrating T cells, with enhanced TNF-α and IL-2 and reduced IL-4 and IL-10 expression.CONCLUSIONNeoadjuvant chemotherapy drives intratumoral T cells toward a proinflammatory profile. Combinational treatment strategies incorporating immunotherapy in neoadjuvant regimens may unleash more effective antitumor responses and improve prognosis of pancreatic cancer.FUNDINGThis work was supported by the Jung Foundation for Science and Research, the Monika Kutzner Foundation, the German Research Foundation (SE2980/5-1), the German Cancer Consortium, and the Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden.

Advance of T regulatory cells in tumor microenvironment remodeling and immunotherapy in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is highly aggressive, deadly, and is rarely diagnosed early. Regulatory T cells (Treg) are a multifunctional class of immunosuppressive T cells that help maintain immunologic homeostasis and participate in autoimmune diseases, transplants, and tumors. This cell type mediates immune homeostasis, tolerance, and surveillance and is associated with poor outcomes in PDAC. Tregs remodel the tumor immune microenvironment, mediate tumor immune escape, and promote tumor invasion and metastasis. A promising area of research involves regulating Tregs to reduce their infiltration into tumor tissues. However, the complexity of the immune microenvironment has limited the efficacy of immunotherapy in PDAC. Treg modulation combined with other treatments is emerging. This review summarizes the mechanisms of Tregs activity in tumor immune microenvironments in PDAC and the latest developments in immunotherapy and clinical trials.

Genetics and Therapeutic Responses to Tumor-Infiltrating Lymphocyte Therapy of Pancreatic Cancer Patient-Derived Xenograft Models

Background and Aims

Pancreatic cancer is the seventh leading cause of cancer-related deaths worldwide. Checkpoint immunotherapy has not yet shown encouraging results in pancreatic cancer possibly because of a poor immunogenicity and/or an immune suppressive microenvironment. The aim of this study was to develop patient-derived xenograft (PDX) models, compare their genetics to the original biopsies, and assess if autologous tumor-infiltrating lymphocytes (TILs) would have antitumoral activity in pancreatic cancer.

Methods

We subcutaneously transplanted tumors from 29 patients into NOG mice to generate PDX models. We established TIL cultures and injected them into PDX mice. We analyzed histology and genetics of biopsies and PDX tumors.

Results

Tumor growths were confirmed in 11 of 29 transplantations. The PDX tumors histologically resembled their original biopsies, but because stromal cells in the PDX model tumors were from mouse, their gene expression differed from the original biopsies. Immune checkpoint ligands other than programmed death ligand-1 (PD-L1) were expressed in pancreatic cancers, but PD-L1 was rarely expressed. When it was expressed, it correlated with tumor take in PDX models. One of the 3 tumors that expressed PD-L1 was an adenosquamous cancer, and another had a mismatch repair deficiency. TILs were expanded from 6 tumors and were injected into NOG or human interleukin-2 transgenic-NOG mice carrying PDX tumors. Regression of tumors could be verified in human interleukin-2 transgenic-NOG mice in 3 of the 6 PDX models treated with autologous TILs, including the adenosquamous PDX model.

Conclusion

PDX models of pancreatic cancer can be used to learn more about tumor characteristics and biomarkers and to evaluate responses to adoptive cell therapy and combination therapies. The major benefit of the model is that modifications of T cells can be tested in an autologous humanized mouse model to gain preclinical data to support the initiation of a clinical trial.

Preclinical Characterization and Phase I Trial Results of a Bispecific Antibody Targeting PD-L1 and 4-1BB (GEN1046) in Patients with Advanced Refractory Solid Tumors

Checkpoint inhibitors (CPI) have revolutionized the treatment paradigm for advanced solid tumors; however, there remains an opportunity to improve response rates and outcomes. In preclinical models, 4-1BB costimulation synergizes with CPIs targeting the programmed cell death protein 1 (PD-1)/programmed cell death ligand 1 (PD-L1) axis by activating cytotoxic T-cell-mediated antitumor immunity. DuoBody-PD-L1×4-1BB (GEN1046) is an investigational, first-in-class bispecific immunotherapy agent designed to act on both pathways by combining simultaneous and complementary PD-L1 blockade and conditional 4-1BB stimulation in one molecule. GEN1046 induced T-cell proliferation, cytokine production, and antigen-specific T-cell-mediated cytotoxicity superior to clinically approved PD-(L)1 antibodies in human T-cell cultures and exerted potent antitumor activity in transplantable mouse tumor models. In dose escalation of the ongoing first-in-human study in heavily pretreated patients with advanced refractory solid tumors (NCT03917381), GEN1046 demonstrated pharmacodynamic immune effects in peripheral blood consistent with its mechanism of action, manageable safety, and early clinical activity [disease control rate: 65.6% (40/61)], including patients resistant to prior PD-(L)1 immunotherapy.

SIGNIFICANCE

DuoBody-PD-L1×4-1BB (GEN1046) is a first-in-class bispecific immunotherapy with a manageable safety profile and encouraging preclinical and early clinical activity. With its ability to confer clinical benefit in tumors typically less sensitive to CPIs, GEN1046 may fill a clinical gap in CPI-relapsed or refractory disease or as a combination therapy with CPIs. See related commentary by Li et al., p. 1184. This article is highlighted in the In This Issue feature, p. 1171.

Tumor-Derived Exosomes Modulate Primary Site Tumor Metastasis

Tumor-derived exosomes (TDEs) are actively produced and released by tumor cells and carry messages from tumor cells to healthy cells or abnormal cells, and they participate in tumor metastasis. In this review, we explore the underlying mechanism of action of TDEs in tumor metastasis. TDEs transport tumor-derived proteins and non-coding RNA to tumor cells and promote migration. Transport to normal cells, such as vascular endothelial cells and immune cells, promotes angiogenesis, inhibits immune cell activation, and improves chances of tumor implantation. Thus, TDEs contribute to tumor metastasis. We summarize the function of TDEs and their components in tumor metastasis and illuminate shortcomings for advancing research on TDEs in tumor metastasis.

Correlation and prognostic implications of intratumor and tumor draining lymph node Foxp3+ T regulatory cells in colorectal cancer

BACKGROUND

The prognostic value of intratumor T regulatory cells (Tregs) in colorectal cancer (CRC) was previously reported, but the role of these cells in tumor draining lymph nodes (TDLNs) was less addressed.

METHODS

A total of 150 CRC stages I-IV were retrospectively enrolled. Intratumor and TDLN Tregs were examined by immunohistochemical assay. The association of these cells was estimated by Pearson correlation. Survival analyses of subgroups were conducted by Kaplan-Meier curves, and the log-rank test and risk factors for survival were tested by the Cox proportional hazard model.

RESULTS

High accumulation of Tregs in tumors was significant in patients with younger age and good histological grade, where enrichment of these cells in TDLNs was more apparent in those with node-negative disease and early TNM stage disease, both of which were more common in early T stage cases. A significant correlation of intratumoral and TDLN Tregs was detected. Patients with higher intratumoral Tregs displayed significantly better PFS and OS than those with lower Tregs. However, no such differences were found, but a similar prognostic prediction trend was found for these cells in TDLNs. Finally, intratumoral Tregs were an independent prognostic factor for both PFS (HR = 0.97, 95% CI 0.95-0.99, P < 0.01) and OS (HR = 0.98, 95% CI 0.95-1.00, P = 0.04) in the patients.

CONCLUSIONS

Higher intratumor Tregs were associated with better survival in CRC. Although no such role was found for these cells in TDLNs, the positive correlation and similar prognostic prediction trend with their intratumoral counterparts may indicate a parallelized function of these cells in CRC.

The Lymph Node Microenvironment May Invigorate Cancer Cells With Enhanced Metastatic Capacities

Cancer metastasis, a typical malignant biological behavior involving the distant migration of tumor cells from the primary site to other organs, contributed majorly to cancer-related deaths of patients. Although constant efforts have been paid by researchers to elucidate the mechanisms of cancer metastasis, we are still far away from the definite answer. Recently, emerging evidence demonstrated that cancer metastasis is a continuous coevolutionary process mediated by the interactions between tumor cells and the host organ microenvironment, and epigenetic reprogramming of metastatic cancer cells may confer them with stronger metastatic capacities. The lymph node served as the first metastatic niche for many types of cancer, and the appearance of lymph node metastasis predicted poor prognosis. Importantly, multiple immune cells and stromal cells station and linger in the lymph nodes, which constitutes the complexity of the lymph node microenvironment. The active cross talk between cancer cells and immune cells could happen unceasingly within the metastatic environment of lymph nodes. Of note, diverse immune cells have been found to participate in the formation of malignant properties of tumor, including stemness and immune escape. Based on these available evidence and data, we hypothesize that the metastatic microenvironment of lymph nodes could drive cancer cells to metastasize to further organs through epigenetic mechanisms.

Clinical Significance of Tumor-Infiltrating Conventional and Plasmacytoid Dendritic Cells in Pancreatic Ductal Adenocarcinoma

Simple Summary

The tumor immune contexture plays a pivotal role for the clinical outcome of cancer patients and the efficacy of various treatment modalities. Dendritic cells (DCs) represent a major component of the tumor immune architecture that can either efficiently promote antitumor immunity or contribute to immunosuppression. Here, we investigated the frequency, spatial organization, and clinical significance of tumor-infiltrating conventional DCs type 1 (cDC1s) and type 2 (cDC2s) and plasmacytoid DCs (pDCs) in pancreatic ductal adenocarcinoma (PDAC). A higher frequency of whole tumor area (WTA)- and tumor stroma (TS)-infiltrating cDC1s, and of intraepithelial tumor-infiltrating cDC2s, was significantly associated with improved survival. Furthermore, a higher density of both WTA- and TS-infiltrating cDC1s and pDCs emerged as an independent prognostic factor for better survival. These results provide evidence that tumor-infiltrating DCs are associated with survival of PDAC patients and may support the design of novel DC-based immunotherapeutic strategies.

Abstract

Dendritic cells (DCs) play a key role in the orchestration of antitumor immunity. Activated DCs efficiently enhance antitumor effects mediated by natural killer cells and T lymphocytes. Conversely, tolerogenic DCs essentially contribute to an immunosuppressive tumor microenvironment. Thus, DCs can profoundly influence tumor progression and clinical outcome of tumor patients. To gain novel insights into the role of human DCs in pancreatic ductal adenocarcinoma (PDAC), we explored the frequency, spatial organization, and clinical significance of conventional DCs type 1 (cDC1s) and type 2 (cDC2s) and plasmacytoid DCs (pDCs) in primary PDAC tissues. A higher density of whole tumor area (WTA)- and tumor stroma (TS)-infiltrating cDC1s was significantly associated with better disease-free survival (DFS). In addition, an increased frequency of intraepithelial tumor-infiltrating cDC2s was linked to better DFS and overall survival (OS). Furthermore, an increased density of WTA- and TS-infiltrating pDCs tended to improve DFS. Moreover, a higher frequency of WTA- and TS-infiltrating cDC1s and pDCs emerged as an independent prognostic factor for better DFS and OS. These findings indicate that tumor-infiltrating DCs can significantly influence the clinical outcome of PDAC patients and may contribute to the design of novel treatment options that target PDAC-infiltrating DCs.

LAG-3-Expressing Tumor-Infiltrating T Cells Are Associated with Reduced Disease-Free Survival in Pancreatic Cancer

Simple Summary

In light of the majority of pancreatic cancer patients not responding to current immune checkpoint blockade, alternative immunotherapeutic targets need to be identified. In this study, we employed multiplex immunofluorescence to investigate the expression of co-stimulatory and inhibitory receptors by tumor-infiltrating T cells in human pancreatic cancer. A comprehensive analysis of the receptor pattern on tumor-infiltrating T cells is essential for the development of new therapeutic strategies, as well as personalized immunotherapy, to identify patients who are likely to benefit from targeting specific immune receptors.

Abstract

T cells are the predominant immune cell population in the pancreatic tumor microenvironment. High CD8⁺ and Th1-polarized CD4⁺ T cell infiltration is associated with prolonged survival in human pancreatic ductal adenocarcinoma (PDAC). However, the expression pattern of co-stimulatory and inhibitory receptors by PDAC-infiltrating T cells and their prognostic significance are not well defined. In this study, we employed multiplex immunofluorescence to investigate the intratumoral expression of the co-stimulatory receptor inducible T-cell co-stimulator (ICOS), the inhibitory receptors lymphocyte-activation gene 3 (LAG-3), programmed death 1 (PD-1), and V-domain immunoglobulin suppressor of T cell activation (VISTA) by tumor-infiltrating T cells (CD3) in a cohort of 69 patients with resected PDAC. T cells were enriched particularly within the stromal area and were highly heterogeneous across tumors. Further, T cells were associated with prolonged disease-free survival (DFS). However, LAG-3 expression by PDAC-infiltrating T cells was correlated with reduced DFS. Our study highlights the biological importance of LAG-3 expression by tumor-infiltrating T cells. LAG-3⁺ T cells may represent a novel prognostic marker and a particularly attractive target for immunotherapeutic strategies in PDAC.